Зарубежная периодика по тематике ИПИ РАН
Выпуск № 3, июль 2006 г.
Материалы подготовлены лаб. 13
Журнал IEEE Transactions on Automatic Control
Feb 2005, Vol. 50 Issue 2
Труды Института Инженеров по Электротехнике и Электронике (США)
«Автоматическое управление»
Том 50, вып. 2 (Февраль 2005 г.)
СТАТЬИ
1. Встраивания конечных автоматов при непараллельном обнаружении и идентификации
ошибок.
Finite-State Machine Embeddings for Nonconcurrent Error Detection and Identification.
By: Hadjicostis, Christoforos N.. p142-153, 12p
Ключевые слова: DIGITAL electronics, FAULT location (Engineering), MECHANICS, RELIABILITY
(Engineering), SPECIFICATIONS, TRANSIENTS (Dynamics)
Author-Supplied Keywords: fault tolerance, finite-state machines (FSMs), nonconcurrent error detection and
correction, transient faults, Error recovery
Abstract: In digital sequential systems that operate over several time steps, a state-transition fault at any lime
step during the operation of the system can corrupt its state and render its future functionality useless. Such
state-transition faults are usually handled by embedding the given sequential system into a larger one, in a way
that preserves the state evolution and properties of the original system while enabling an external mechanism to
perform checks to detect, identify and correct errors in the encoded state of this redundant system. Checking is
typically performed concurrently (i.e., at the end of each lime step) and can potentially cause high power
consumption or an overall slowdown in the system; more importantly, concurrent checking imposes significant
reliability requirements on the error-detection/identification mechanism. In this paper, we develop a
methodology for systematically constructing embeddings of finite-state machines so that the external
mechanism can capture transient state-transition faults via checks that are performed in a nonconcurrent manner
(e.g., periodically instead of every time step). More specifically, by characterizing nonconcurrent errordetecting/identifying capabilities in terms of state encoding constraints and redundant dynamics, the proposed
approach can be used to construct a redundant version of the given finite-state machine (FSM) that allows the
external mechanism to detect and identify errors due to past state-transition faults based on an analysis of the
current, possibly corrupted FSM state. As a result, the checker in such designs can operate at a slower speed
than the rest of the system which relaxes the stringent requirements on its reliability. [ABSTRACT FROM
AUTHOR]
2. Обзор тематики, связанной с системами последовательной обработки цифровой информации,
такими как контроллеры и микроконтроллеры.
Scanning the Issue. p143-143, 1p;
Ключевые слова: AUTOMATIC control, COMMUNICATION, CONVERGENCE, DIGITAL electronics,
ELECTRIC controllers, NONLINEAR systems
Abstract: The article presents information on topics on which articles of this issue of the periodical are
published. In digital sequential systems, such as embedded controllers and microcontrollers, a transient fault
can corrupt the system state. Detecting a corrupted system state and identifying the fault in a timely manner is
important for preventing the effects of the propagation of the fault. One of the paper introduces several
definitions of norm-observability for nonlinear systems and explores relationships among them. These
observability properties involve the existence of a bound on the norm of the state in terms of the norms of the
output and the input on some time interval. The focus of one of the paper is on the development and analysis of
a network model of multiple agents interacting via time-dependent communication links. In the model, each
1
agent updates its current state based upon the current information from neighboring agents. In one of the paper,
the authors develop new criteria for deriving uniform convergence in uniformly stable time-varying systems.
3. Нелинейные нормо-наблюдаемые представления и устойчивость систем маршрутизации.
Nonlinear Norm-Observability Notions and Stability of Switched Systems.
By: Hespanha, Joao P.; Liberzon, Daniel; Angeli, David; Sontag,p154-168, 15p;
Ключевые слова: AMPLIFIERS, Vacuum-tube, ELECTRONICS, FEEDBACK (Electronics), NONLINEAR
systems, SWITCHING power supplies, NONLINEAR models
Author-Supplied Keywords: nonlinear system, observability, switched system, LaSalle's stability theorem
Abstract: This paper proposes several definitions of "norm-observability" for nonlinear systems and explores
relationships among them. These observability properties involve the existence of a bound on the norm of the
state in terms of the norms of the output and the input on some time interval. A Lyapunov-like sufficient
condition for norm-observability is also obtained. As an application, we prove several variants of LaSalle's
stability theorem for switched nonlinear systems. These results are demonstrated to be useful for control design
in the presence of switching as well as for developing stability results of Popov type for switched feedback
systems. [ABSTRACT FROM AUTHOR]
4. Устойчивость мультиагентных систем с зависимыми по времени коммуникационными
связями.
Stability of Multiagent Systems With Time-Dependent Communication Links.
By: Moreau, Luc. p169-182, 14p;
Ключевые слова: COMMUNICATION, CONVERGENCE, LYAPUNOV functions, STRUCTURAL
stability, SYNCHRONIZATION, TIME measurements
Author-Supplied Keywords: set-valued Lyapunov theory, stability analysis, swarms, synchronization.
Abstract: We study a simple but compelling model of network of agents interacting via time-dependent
communication links. The model finds application in a variety of fields including synchronization, swarming
and distributed decision making. In the model, each agent updates his current state based upon the current
information received from neighboring agents. Necessary and/or sufficient conditions for the convergence of
the individual agents' states to a common value are presented, thereby extending recent results reported in the
literature. The stability analysis is based upon a blend of graph-theoretic and system-theoretic tools with the
notion of convexity playing a central role. The analysis is integrated within a formal framework of set-valued
Lyapunov theory, which may be of independent interest. Among others, it is observed that more
communication does not necessarily lead to faster convergence and may eventually even lead to a loss of
convergence, even for the simple models discussed in the present paper. [ABSTRACT FROM AUTHOR]
5. Встроенная теорема Матросова и существование возбуждения равномерной сходимости в
устойчивых неавтономных системах.
A Nested Matrosov Theorem and Persistency of Excitation for Uniform Convergence in Stable
Nonautonomous Systems.
By: Loria, Antonio; Panteley, Elena; Popovic, Dobrivoje; Teel, Andrew R.. p183-198, 16p;
Ключевые слова: ASYMPTOTES, BESSEL functions, CALCULUS, CURVES, Plane, DIFFERENTIAL
equations, LINEAR systems
Author-Supplied Keywords: nonholonomic systems, time- varying systems, uniform stability.
Abstract: A new infinitesimal sufficient condition is given for uniform global asymptotic stability (UGAS) for
time-varying non- linear systems. it is used to show that a certain relaxed persistency of excitation condition,
called uniform -persistency of excitation (U-PE), is sufficient for uniform global asymptotic stability in
certain situations. U-PE of the right-hand side of a time-varying differential equation is also shown to be
necessary under a uniform Lipschitz condition. The infinitesimal sufficient condition for UGAS involves the
inner products of the flow field with the gradients of a finite number of possibly sign-indefinite, locally
Lipschitz Lyapunov-like functions. These inner products are supposed to be bounded by functions that have a
2
certain nested, or triangular, negative semidefinite structure. This idea is reminiscent of a previous idea of
Matrosov who supplemented a Lyapunov function having a negative semidefinite derivative with an additional
function having a derivative that is "definitely nonzero" where the derivative of the Lyapunov function is zero.
For this reason, we call the main result a nested Matrosov theorem. The utility of our results on stability
analysis is illustrated through the well-known case-study of the nonholonomic integrator. [ABSTRACT FROM
AUTHOR]
6. Управление в Гамильтониановских системах с множественными задержками по входу\выходу
путем декомпозиции адобовских операторов.
H Control of Systems With Multiple I/O Delays via Decomposition to Adobe Problems.
By: Meinsma, Gjerrit; Mirkin, Leonid.Vol. p199-211, 13p;
Ключевые слова: AUTOMATIC control, AUTOMATION, DELAY differential equations, DELAY lines,
DISCRETE-time systems, FEEDBACK control systems
Author-Supplied Keywords: H control, time-delay systems. Dead-time compensation
Abstract: In this paper, the standard (four-block) H^ control problem for systems with multiple
input-output delays in the feed- back loop is studied. The central idea is to see the multiple delay operator as a
special series connection of elementary delay operators, called the adobe delay operators. The adobe delay case
is solved and thereby the general case is solved as a nested set of solutions to adobe delay problems.
[ABSTRACT FROM AUTHOR]
7. Замечания по вопросу проектирования систем дескрипторов с ошибками и неизвестными
входами.
Technical Notes and Correspondence.
By: Koenig, D.. p212-217, 6p;
Ключевые слова: ALGEBRA, AUTOMATIC control, DIFFERENTIAL equations, Linear, LINEAR
systems, MATHEMATICAL analysis, SYSTEM theory
Author-Supplied Keywords: proportional-integral (PI) observer, robustness. Descriptor systems
Abstract: In this note, the problem of observer design for linear descriptor systems with faults and unknown
inputs is considered. First, it is considered that the fault vector function f is &ssline; times piecewise
continuously differentiable. If the &ssline;th time derivative of f is null, then a integral actions are included into
a Luenberger observer, which is designed such that it estimates simultaneously the state, the fault, and its finite
derivatives face to unknown inputs. Second, when the fault is not lime piecewise continuously differentiable
but bounded (like actuator noise) or &ssline;th lime derivative of fault is not null but bounded too, a high gain
observer is derived to attenuate the fault impact in estimation errors. The considered faults may be unbounded,
may not be determinist, and faults and unknown inputs may affect the state dynamic and plant outputs.
Sufficient conditions for the existence of such observer are given. Results are illustrated with a differential
algebraic power system. [ABSTRACT FROM AUTHOR]
8. Зависимая от величины задержки экспоненциальная устойчивость в стохастических системах с
переменной по времени задержкой, нелинейностью и марковской маршрутизацией.
Delay-Dependent Exponential Stability of Stochastic Systems With Time-Varying Delay, Nonlinearity, and
Markovian Switching.
By: Dong Yue; Qing-Long Han.p217-222, 6p;
Ключевые слова: DELAY differential equations, FUNCTIONAL differential equations, MATRICES,
STOCHASTIC analysis, STOCHASTIC processes, SYSTEM analysis
Author-Supplied Keywords: Markov chain, stability, Stochastic systems, time delay. Linear matrix inequality
(LMI)
Abstract: The problem of delay-dependent stability in the mean square sense for stochastic systems with timevarying delays, Markovian switching and nonlinearities is investigated. Both the slowly time-varying delays
and fast time-varying delays are considered. Based on a linear matrix inequality approach, delay-dependent
3
stability criteria are derived by introducing some relaxation matrices which can be chosen properly to lead to a
less conservative result. Numerical examples are given to illustrate the effectiveness of the method and
significant improvement of the estimate of stability limit over some existing results in the literature.
[ABSTRACT FROM AUTHOR]
9. Робастное управление по выходу в сингулярных нелинейных системах с помощью нелинейной
внутренней модели.
Robust Output Regulation of Singular Nonlinear Systems via a Nonlinear Internal Model. By: Sulin Pang; Jie
Huang; Yuanhuai Bai.p222-228, 7p;
Ключевые слова: ALGEBRA,
POLYNOMIALS, ROBUST control
AUTOMATIC
control,
EQUATIONS,
NONLINEAR
systems,
Author-Supplied Keywords: output regulation problem, robust control, singular systems.
Abstract: The robust output regulation problem for singular nonlinear systems has been studied recently under
a restrictive assumption that the solution of the regulator equations is polynomial. This assumption essentially
limits the nonlinear systems to contain only polynomial nonlinearities. In this note, we will further show that
the polynomial assumption can be replaced by a much milder condition. The new condition applies to a larger
class of nonpolynomial nonlinear systems, thus significantly improving the existing result. [ABSTRACT
FROM AUTHOR]
10. Линейные функциональные наблюдатели в системах с задержками в переменных состояния:
случай дискретного времени.
Linear Functional Observers for Systems With Delays in State Variables: The Discrete-Time Case.
By: Darouach, M.Vol. p228-233, 6p;
Ключевые слова: DIFFERENTIAL equations, Linear, FEEDBACK control systems, INEQUALITIES
(Mathematics), LINEAR systems, SYSTEM theory, TIME delay systems
Author-Supplied Keywords: discrete time-delay systems, functional observer, linear matrix inequality (LMI)
stability. Bilinear matrix inequality (BMI)
Abstract: This note extends to the discrete-time case the design of linear functional state observers, recently
developed for continuous-time delay systems. Sufficient conditions for the stability dependent of delays and
stability independent of delays are derived using linear and bilinear matrix inequalities [(LMIs) and (BMIs)]
formulations. [ABSTRACT FROM AUTHOR]
11. Отслеживание траектории в неминимально-фазовых системах, устраняющее пределы
эффективности.
Path-Following for Nonminimum Phase Systems Removes Performance Limitations.
By: Aguiar, A. Pedro; Hespanha, Joao P.; Kokotovic, Petar V.. p234-239, 6p
Ключевые слова: GEOMETRY, EUCLID'S Elements, MATHEMATICS, TIME measurements, TIMING
circuits, ANGLES (Geometry)
Author-Supplied Keywords: nonminimum phase systems, path-following, reference-tracking, Cheap-Control
Abstract: We highlight an essential difference between path-following and reference-tracking for nonminimum
phase systems. It is well known that in the reference-tracking, for nonminimuin phase systems, there exists a
fundamental performance limitation in terms of a lower bound on the L₂ -norm of the tracking
error, even when the control effort is free. We show that this is not the case for the less stringent path-following
problem, where the control objective is to force the output to follow a geometric path without a timing law
assigned to it. Furthermore, the same is true even when an additional desired speed assignment is imposed.
[ABSTRACT FROM AUTHOR]
12. Обнаружение ошибок в линейных периодических системах с дискретным временем.
Fault Detection of Linear Discrete-Time Periodic Systems.
By: Zhang, P.; Ding, S. X.; Wang, G. Z.; Zhou, D. H.. p239-244, 6p
4
Ключевые слова: DIFFERENTIAL equations, Linear, DYNAMIC testing, FAULT location (Engineering),
LINEAR systems, RICCATI equation, SYSTEM theory
Author-Supplied Keywords: linear discrete-time systems, periodic systems, residual generation, robustness,
Fault detection
Abstract: In this note, an approach to the design of optimal fault detection systems for linear discrete-time
periodic systems is proposed, which leads to an optimized compromise between robustness to unknown
disturbances and sensitivity to faults. The needed computation mainly consists in solving a difference periodic
Riccati system. The proposed approach is finally illustrated by a numerical example. [ABSTRACT FROM
AUTHOR]
13. Проблемы распределенного управления рулевым двигателем космического аппарата.
Spacecraft Thruster Control Allocation Problems. By: Servidia, Pablo A.; Pena, Ricardo Sanchez. p245-249,
5p;
Ключевые слова: ALGORITHMS, MATHEMATICAL analysis, MATHEMATICAL optimization,
MECHANICS, ROTATIONAL motion (Rigid dynamics), SPACE vehicles
Author-Supplied Keywords: spacecraft, thruster.Control allocation
Abstract: We consider the control allocation problem in a spacecraft thruster configuration. It consists on the
determination of the force command to be sent to each thruster in order to point the total torque and/or thrust
vectors. Here, we state four possible practical problems and propose a control allocation algorithm based on a
subgradient optimization, which is shown to be faster than existing allocators. [ABSTRACT FROM AUTHOR]
14. Обеспечение устойчивости линейных систем с дискретным временем за счет статической
обратной связи по выходу с Гамильтониановской эффективностью.
Static Output Feedback Stabilization With H Performance for Linear Discrete-Time Systems.
By: Bara, G. Iulia; Boutayeb, Mohamed. p250-254, 5p;
Ключевые слова: ALGEBRA, FEEDBACK (Electronics), LINEAR operators, MATHEMATICS,
MATRICES, STATICS
Author-Supplied Keywords: linear matrix inequality (LMI) approach, static output feedback (SOF). Discretetime systems
Abstract: This note presents a new sufficient condition for the static output feedback stabilization of linear
discrete-time systems. This new condition is expressed as a linear matrix inequality feasibility problem and
hence easily tractable numerically. An extension of this condition is given in order to incorporate
&hamlit;_? performance objectives. The applicability of the proposed approach is shown through
numerical examples and compared to some recent methods. [ABSTRACT FROM AUTHOR]
15. Глобальная экспоненциальная устойчивость через обратную связь по выходу в классе
нелинейных систем.
Global Exponential Stabilization of a Class of Nonlinear Systems by Output Feedback.
By: Ho-Lim Choi; Jong-Tae Lim. p255-257, 3p;
Ключевые слова: EXPONENTIAL functions, FEEDBACK (Electronics), FEEDBACK control systems,
LOGARITHMS, NONLINEAR system, TRANSCENDENTAL functions
Author-Supplied Keywords: output feedback control, Global exponential stabilization
Abstract: This work extends the existing output feedback stabilization schemes for the systems in a "perturbed
chain-of-integrator" form. In particular, we further relax the triangular-type conditions imposed on the
perturbed terms and analyze the robust property of the linear output feedback control law using the newly
proposed condition. [ABSTRACT FROM AUTHOR]
16. Ограниченный алгоритм на основе модели управления с упреждением для систем с
неопределенными, изменяющимися во времени параметрами и задержками по состоянию.
Constrained MPC Algorithm for Uncertain Time-Varying Systems With State-Delay.
By: Seung Cheol Jeong; Park, PooGyeon. p257-263, 7p;
5
Ключевые слова: AUTOMATIC control, ALGORITHMS, AUTOMATION, FEEDBACK control systems,
MATHEMATICAL optimization, MATRICES
Author-Supplied Keywords: input constraint, model predictive control (MPC), state dela, uncertainty, Closedloop stability
Abstract: In this note, we present a model predictive control (MPC) algorithm for uncertain time-varying
systems with input constraints and state- delay. Uncertainty is assumed to be polytopic, and delay is assumed to
be, unknown but with a known upper bound. For a memoryless state-feedback MPC law, we define an
optimization problem that minimizes a cost function and relaxes it to two other optimization problems by
finding an upper bound of the cost function. One is solvable and the other is not. We prove equivalence and
feasibilities of the two optimization problems under a certain assumption on the weighting matrix. Based on
these properties and optimality, we show that feasible MPC from the optimization problems stabilizes the
closed-loop system. Then, we present an improved MPC algorithm that includes relaxation procedures of the
assumption on the weighting matrix and stabilizes the closed-loop system. Finally, a numerical example
illustrates the performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]
17. Поддающиеся вычислению законы стохастического управления мощностью в беспроводных
системах коммуникации.
Computationally Tractable Stochastic Power Control Laws in Wireless Communications.
By: Minyi Huang; Malhanie, Roland P.; Caines, Peter E.. p263-268, 6p;
Ключевые слова: CALCULUS of variations, HAMILTON-Jacobi equations, MATHEMATICAL
optimization, MECHANICS, STOCHASTIC analysis, STOCHASTIC processes
Author-Supplied Keywords: lognormal fading channel, power control, Hamilton-Jacobi-Bellman (HJB)
equations
Abstract: This note considers uplink power control for lognormal fading channels by a stochastic control
approach. We seek approximate solutions to the Hamilton-Jacobi-Bellman (RIB) equation in terms of a local
polynomial approximation, and solve a two user system for illustration. An important issue for practical
systems is to reduce implementational complexity when operating in large population conditions; we show that
a single user based control design may be applied to such systems for partially decentralized optimization.
[ABSTRACT FROM AUTHOR]
18. Экспоненциальные оценки в запаздывающих системах временной задержки: подход,
основанный на линейной матрице неравенств.
Exponential Estimates for Retarded Time-Delay Systems: An LMI Approach.
By: Mondie, S.; Kharitonov, V. L.. p268-273, 6p;
Ключевые слова: CONTROL theory, DISTRIBUTION (Probability theory), EXPONENTIAL families
(Statistics), LINEAR systems, LYAPUNOV functions, LYAPUNOV stability
Author-Supplied Keywords: linear matrix inequalities (LMIs), Lyapunov-Krasovskii functiona, time-delay
system.Exponential estimate
Abstract: Exponential estimates and sufficient conditions for the exponential stability of linear time delay
systems are given. The proof make use of Lyapunov-Krasovskii functionals and the conditions are expressed in
terms of linear matrix inequalities. [ABSTRACT FROM AUTHOR]
19. Комментарии относительно модели приведения Рауса-Пейда для интервальных систем.
Comments on "On Routh -- Pade Model Reduction of Interval Systems.
By: Shih-Feng Yang. p273-274, 2p;
Ключевые слова: CONTROL theory, LYAPUNOV
MATHEMATICS, NUMERICAL analysis, STABILITY
stability,
MATHEMATICAL
models,
Author-Supplied Keywords: model reductio, Routh table, Interval systems
6
Abstract: A numerical example is given to show that the model reduction method of interval systems proposed
by Dolgin and Zeheb in the above paper cannot guarantee the stability of the reduced-order interval models.
[ABSTRACT FROM AUTHOR]
20. Замечания автора (модель приведения Рауса-Пейда для интервальных систем).
Author's Reply.
By: Dolgin, Yuri. p274-275, 2p;
Ключевые слова: ALGEBRA, APPROXIMATION theory, INTERVAL functions, POLYNOMIALS, SET
functions, GENERALIZATION
Author-Supplied Keywords: model reduction, Routh-Pade approximation, Interval systems
Abstract: The article reports that the existing generalization of the direct Routh table truncation method for
interval systems fails to produce a stable system. Additionally, it was shown how to extend the method to
ensure the stability of the resulting interval system. An omission in the proposed algorithm of building interval
Routh table-the newly calculated line in the table may be inconsistent with the last existing line. Two additional
conditions should be formulated to avoid this situation. To obtain the self-contained interval Routh table one
should replace the first column of the table. The aforementioned additional conditions ensure the stability of the
interval polynomial constructed from the truncated interval Routh table and at the same time argue the claim of
stating that it is impossible to ensure stability of the interval Routh approximants. The point-by-point property
holds only for pairs of rows and not for the span of three rows-and again it is not problematic.
21. Комментарии по вопросу квадратичной устойчивости и устойчивости динамических
интервальных систем.
Comments on "Quadratic Stability and Stabilization of Dynamic Interval Systems.".
By: Guang-Hong Yang; Kai-Yew Lum. p276-277, 2p;
Ключевые слова: INEQUALITIES (Mathematics),
MATHEMATICS, SET functions, STABILITY
INTERVAL
functions,
LINEAR
systems,
Author-Supplied Keywords: linear matrix inequality (LMI, quadratic stability, quadratic stabilization, Interval
systems
Abstract: In the above paper, it was claimed that the necessary and sufficient conditions for the quadratic
stability and stabilization of dynamic interval systems are given in terms of linear matrix inequalities (LMIs). In
this note, numerical examples are presented to show that the necessity of the conditions given in [1] does not
hold. [ABSTRACT FROM AUTHOR]
22. Сингулярные траектории и их роль в теории управления – Бернард Боннар и Моник Чиба.
Singular Trajectories and Their Role in Control Theory -- Bernard Bonnard and Monique Chyba.
By: Sussmann, Hector J.. p278-279, 2p;
BOOKS -- Reviews
Ключевые слова:*NONFICTION
Reviews & Products: SINGULAR Trajectories & Their Role in Control Theory (Book), People: BONNARD,
Bernard CHYBA, Monique
Abstract: Reviews the book "Singular Trajectories and Their Role in Control Theory," by Bernard Bonnard
and Monique Chyba.
7
Журнал IEEE Transactions on Computers, Feb2005, Vol. 54 Issue 2
Труды Института Инженеров по Электротехнике и Электронике (США)
«Вычислительная техника»
Том 54, вып. 2 (Февраль 2005 г.)
1. Редакционная статья.
Editor's Note.
By: Prasanna, Viktor K.; Lombardi, Fabrizio. p97-97, 1p;
Ключевые слова: INFORMATION technology, INTEGRATED circuits
Abstract: Presents an introduction to the February 2005 issue of the periodical "IEEE Transactions on
Computers."
2. Последовательный многоразрядный множитель нормального базиса невысокой сложности.
Low Complexity Word-Level Sequential Normal Basis MultipIier's.
By: Reyhani-Masoleh, Arash; Hasan, M. Anwar. P. 98-110, 13p;
Ключевые слова: COMPUTER input-output equipment, CRYPTOGRAPHY, FINITE fields (Algebra),
MULTIPLIERS (Mathematical analysis), RESEARCH, COMPUTER systems
Abstract: For efficient hardware implementation of finite field arithmetic units, the use of a normal basis is
advantageous. In this paper, two classes of architectures for multipliers over the finite field
GF(2^m) are proposed. These multipliers are of sequential type, i.e., after receiving the coordinates
of the two input field elements, they go through k, 1  k  in, iterations (i.e., clock cycles) to finally yield all the
coordinates of the product in parallel. The value of k depends on the word size to For =[m/k] 1, these
multipliers are highly area efficient and require fewer number of logic gates even when compared with the most
area efficient multipliers available in the open literature. This makes the proposed multipliers suitable for
applications where the value of m is large but space is of concern, e.g., resource constrained cryptographic
systems. Additionally, if the field dimension in is composite, i.e., m = kn, then the extension of one class of the
architectures yields a highly efficient multiplier over composite fields. [ABSTRACT FROM AUTHOR]
3. Вторичное декодирование системы счисления для множителя высшего разряда.
Secondary Radix Recodings for Higher Radix Multipliers.
By: Seidel, Peter-Michael; McFearin, Lee D.; Matula, David W.. p111-123, 13p;
Ключевые слова: COST, METHODOLOGY, MULTIPLIERS (Mathematical analysis), PROBLEM solving,
RESEARCH, THEORY
Abstract: For progressively higher radices, the reduction in partial products obtained by the well-known
modified Booth multiplier recoding is offset by the need to precompute a rapidly increasing store of odd
multiples of the multiplicand as inputs to each partial product generator (PPG). We propose secondary radix
multiplier recoding schemes reducing the number of odd multiples required in the store for very high radix
recodings (e.g., radix 2^r for 5  r  16). The proposed recoding schemes allow reduction of the
number of partial products in the implementation by factors between and beyond the reduction factors of 2, 3,
and 4 that can be achieved by traditional Booth recodings to radices 4, 8, and 16, respectively. We develop the
theory of these recodings and provide methodology for secondary radix selection. Finally, we summarize
latency and cost evaluations of selected implementations indicating potential cost and performance/cost
advantages for practical operand sizes. [ABSTRACT FROM AUTHOR]
4. Оптимальное двоичное представление пары целых чисел при обходе слева-направо.
Left-to-Right Optimal Signed-Binary Representation of a Pair of Integers.
By: Xiaoyu Ruan; Katti, Rajendra S.. p124-131, 8p;
Ключевые слова: BINARY system
METHODOLOGY, RESEARCH, THEORY
(Mathematics),
CRYPTOGRAPHY,
CURVES,
Elliptic,
Abstract: The common computation in elliptic curve cryptography (ECC), aP + bQ, is performed by extending
Shamir's method for the computation of the product of powers of two elements in a group. The complexity of
computing aP + bQ is dependent on the joint weight of the binary expansion of positive integers a and b. in this
8
paper, we give a method of finding a minimum joint weight signed- binary representation of a pair of integers.
Our method examines the integers a and b from left to right, thereby making the conversion to signed-binary
form compatible with Shamir's method. This reduces the memory required to perform the computation of aP +
bQ. [ABSTRACT FROM AUTHOR]
5. Повышение производительности монопроцессора путем адаптивного управления частотой
часов.
Uniprocessor Performance Enhancement through Adaptive Clock Frequency Control.
By: Uht, Augustus K.. p132-140, 9p;
Ключевые слова: COMPUTER input-output equipment, COST,
METHODOLOGY, MOTHERBOARDS (Microcomputers), RESEARCH
EXPERIMENTAL
design,
Abstract: Uniprocessor designs have always assumed worst-case operating conditions to set the operating
clock frequency and, hence, performance. However, much more performance can be obtained under typical
operating conditions through experimentation, but such increased frequency operation is subject to the
possibility of system failure and, hence, data loss/corruption. Further, mobile CPUs such as those in cell
phones/internet browsers do not adapt to their current surroundings (varying temperature conditions, etc.) so as
to increase or decrease operating frequency to maximize performance and/or allow operation under extreme
conditions. We present a digital hardware design technique realizing adaptive clock-frequency performanceenhancing digital hardware; the technique can be tuned to approximate performance maximization. The cost is
low and the design is straightforward. Experiments are presented evaluating such a design in a pipelined
uniprocessor realized in a Field programmable Gate Array (FPGA). [ABSTRACT FROM AUTHOR]
6. Локальное и системное воздействие часов на производите
ьность многопроцессорных чипов в режиме одновременной многопотоковой обработки.
Area and System Clock Effects on SMT/CMP Throughput.
By: Burns, James; Gaudiot, Jean-Luc. p141-152, 12p;
Ключевые слова: COMPUTER input-output equipment, EXPERIMENTAL design, METHODOLOGY,
PARALLEL processing (Electronic computers), TECHNOLOGY, COMPUTER systems, SIMULTANEOUS
multithreading processors
Abstract: Two approaches to high throughput processors are Chip Multi-Processing (CMP) and Simultaneous
Multi-Threading (SMI). CMP increases layout efficiency, which allows more functional units and a faster clock
rate. However, CMP suffers from hardware partitioning of functional resources. SMT increases functional unit
utilization by issuing instructions simultaneously from multiple threads. However, a wide-issue SMT suffers
from layout and technology implementation problems. We use silicon resources as our basis for comparison
and find that area and system clock have a large effect on the optimal SMT/CMP design trade. We show the
area overhead of SMT on each processor and how it scales with the width of the processor pipeline and the
number of SMT threads. The wide issue SMT delivers the highest single-thread performance with improved
multithread throughput. However, multiple smaller cores deliver the highest throughput. Also, alternate
processor configurations are explored that trade off SMT threads for other microarchitecture features. The
result is a small increase to single-thread performance, but a fairly large reduction in throughput. [ABSTRACT
FROM AUTHOR]
7. Дешевая и быстродействующая встроенная программа проверки парафазного кода.
Low Cost and High Speed Embedded Two-Rail Code Checker.
By: Omana, Martin; Rossi, Daniele; Metra, Cecilia. p153-164, 10p;
Ключевые слова: COST, ERROR, EXPERIMENTAL design, METHODOLOGY, RESEARCH,
SIMULATION methods
Abstract: In this paper, we propose a compact, high-speed, and highly testable parallel two-rail code checker,
particularly suitable to implementing embedded checkers. In fact, it requires only two input codewords to
satisfy the Totally-self-checking or Strongly code- Disjoint property with respect to a wide set of realistic
internal faults. Our checker can be employed to check the correct operation of a connected functional block
using the two-rail code, to implement the output two-rail code checker of "normal" checkers for unordered
9
codes, or to join together the error messages produced by various checkers (possibly using different codes)
present within the same self-checking system. The behavior of our checker has been verified by means of
electrical level simulations (performed using HSPICE), considering both nominal values and statistical
variations of electrical parameters. We also propose a possible modification to our checker internal structure
that makes it able to provide an output error indication remaining latched until the application of a proper reset
signal. Depending on the considered application and recovery technique to be employed upon the generation of
an error indication at the checker output, one proposed solution or the other may be preferable. [ABSTRACT
FROM AUTHOR]
8. Условные меры диагностируемости больших многопроцессорных систем.
Conditional Diagnosability Measures for Large Multiprocessor Systems.
By: Pao-Lien Lai; Jimmy J.M. Tan; Chien-Ping Chang; Lih-Hsing Hsu. p165-175, 11p;
Ключевые слова: COMPUTER networks, CONCEPTS, ELECTRONIC digital computers, GRAPHIC
methods, INFORMATION technology, MULTIPROCESSORS
Abstract: Diagnosability, has played an important role in the reliability of an interconnection network. The
classical problem of fault diagnosis is discussed widely and the diagnosability of many well-known networks
have been explored. In this paper, we introduce a new measure of diagnosability, called conditional
diagnosability, by restricting that any faulty set cannot contain all the neighbors of any vertex in the graph.
Based on this requirement, the conditional diagnosability of the n-dimensional hypercube is shown to be 4(n 2) + 1, which is about four times as large as the classical diagnosability. Besides, we propose some useful
conditions for verifying if a system is t-diagnosable and introduce a new concept, called a strongly idiagnosable system, under the PMC model. Applying these concepts and conditions, we investigate some tdiagnosable networks which are also strongly t-diagnosable. [ABSTRACT FROM AUTHOR]
9. t/k-диагностируемость ВС графа.
The t/k-Diagnosability of the BC Graphs.
By: Jianxi Fan; Xiaoia Lin. p176-184, 9p; (AN 15956869)
Ключевые слова: ALGORITHMS, COMPUTER security, ELECTRONIC data processing, FAULT-tolerant
computing, MULTIPROCESSORS, RESEARCH, COMPUTER system failures
Abstract: Processor fault diagnosis takes an important role in fault-tolerant computing on multiprocessor
systems. There are two classical diagnosis strategies-the precise strategy and the pessimistic strategy, both of
which are based on the well-known PMC diagnostic model. Nevertheless, the degree of diagnosability of the
system is limited under these two strategies. A better method, called the t/k-diagnosis strategy, is proposed by
Somani and Peleg, in which the identified fault-set is allowed to contain at most k fault-free processors. Using
this diagnosis strategy, the degree of diagnosability of the hypercube increases greatly as the number of the
fault-free processors in the fault-set increases. In this paper, we study the t/k-diagnosability of so-called BC
graphs that include hypercubes crossed cubes, Mabius cubes, and twisted cubes, etc. We show that any ndimensional BC graph is t(n, k)/k-diagnosable when n  4 and 0  k  it, where t(n, k) = (k + 1)n –1/2 (k + 1)(k
+2) + 1. Therefore, the crossed cube, the Mabius cube, and the twisted cube all have the same t/k-diagnosability
as the hypercube. As a result, the algorithms developed for diagnosis on the hypercube may also be used to
diagnose multiprocessor systems whose network topologies are based on BC graphs. [ABSTRACT FROM
AUTHOR]
10. Анализ адаптивности размера строки при параметризированном прямом вложении прямо
отображаемого кэша данных.
Line Size Adaptivity Analysis of Parameterized Loop Nests for Direct Mapped Data Cache.
By: D'Alberto, Paolo; Nicolau, Alexandru; Veidenbaum, Alexander; Gupta, Rajesh. p185-197, 13p;
Ключевые слова: COMPUTER input-output equipment, COMPUTER software, COMPUTER storage
devices, DATABASES, ELECTRONIC data processing, COMPUTER systems
Abstract: Caches are crucial components of modern processors; they allow high-performance processors to
access data fast and, due to their small sizes, they enable low-power processors to save energy-by
circumventing memory accesses. We examine efficient utilization of data caches in an adaptive memory
hierarchy. We exploit data reuse through the static analysis of cache-line size adaptivity. We present an
approach that enables the quantification of data misses with respect to cache-line size at compile-time using
10
(parametric) equations, which model interference. Our approach aims at the analysis of perfect loop nests in
scientific applications; it is applied to direct mapped cache and it is an extension and generalization of the
Cache Miss Equation (CME) proposed by Ghosh et al. (1999). Part of this analysis is implemented in a
software package, STAMINA. We present analytical results in comparison with simulation-based methods and
we show evidence of both the expressiveness and the practicability of the analysis. [ABSTRACT FROM
AUTHOR]
11. Эффективное восстановление в системе резервирования реального времени с переменным
временем исполнения.
Efficient Reclaiming in Reservation-Based Real-Time Systems with Variable Execution Times.
By: Caccamo, Marco; Buttazzo, Giorgio C.; Thomas, Deepu C.. p198-213, 16p;
Ключевые слова: ALGORITHMS, BROADBAND communication
SCHEDULING, SIMULATION methods, COMPUTER systems
systems,
METHODOLOGY,
Abstract: In this paper, we present a general CPU scheduling methodology for managing overruns in a realtime environment, where tasks may have different criticality, flexible timing constraints, shared resources, and
variable execution times. The proposed method enhances the Constant Bandwidth Server (CBS) by providing
two important extensions. First, it includes an efficient bandwidth sharing mechanism that reclaims the unused
bandwidth to enhance task responsiveness, it is proven that the reclaiming mechanism does not violate the
isolation property of the CBS and can be safely adopted to achieve temporal protection even when resource
reservations are not precisely assigned. Second, the proposed method allows the CBS to work in the presence of
shared resources. The enhancements achieved by the proposed approach turned out to be very effective with
respect to classical CPU reservation schemes. The algorithm complexity is O(lnN), where N is the number of
real-time tasks in the system, and its performance has been experimentally evaluated by extensive simulations.
[ABSTRACT FROM AUTHOR]
12. Новое высокоразрядное дерево для многоадресного управления ключами.
A Novel High-Order Tree for Secure Multicast Key Management.
By: Haibin Lu. p214-224, 11p;
Ключевые слова: ALGORITHMS, COMPUTER networks, DATA protection, ELECTRONIC surveillance,
SECURITY systems, MULTICASTING (Computer networks)
Abstract: Multicast is used to deliver packets to a group of users. To prevent users outside the group from
eavesdropping, a group key is maintained to encrypt the group communication, and the group key is changed
(rekeying) when a new. member joins the group or an existing member leaves the group. Re keying costs could
be as high as n a group with n members. The hierarchical key-tree approach is widely used to achieve
logarithmic rekeying costs. However, the key tree has to be kept balanced in order to keep logarithmic rekeying
costs. Goshi and Ladner [8] propose the height-balanced 2-3 tree (a B-tree of order in 3) and found that it has
the best performance among the balancing strategies tested. However, balancing a B-tree [8] after member
joining involves splitting oversized tree nodes and results in (in +2)h worst-Case rekeying cost, where h is the
tree height. We propose an NSBHO (Non-Split Balancing High-Order) tree in which balancing tree after
member joining does not involve node splitting, thus having 2h worst-case rekeying cost. An NSBHO tree is
always balanced and its nodes may not satisfy the node properties of a standard B-tree. Our proposed NSBHO
tree has the same worst- case rekeying cost incurred by a member removing as a B-tree [8] does. Our
experiments show that the NSBHO tree has better average- case rekeying performance and far superior worstcase rekeying performance than a B-tree. [ABSTRACT FROM AUTHOR]
13. Краткая статья по проблеме двоичного вложения.
Brief Contributions.
By: Dimitrakopoulos, Giorgos; Nikolos, Dimitris. p225-231, 7p;
Ключевые слова: EQUATIONS, EXPERIMENTAL design, INTEGRATED circuits -- Very large scale
integration, PROBLEM solving, RESEARCH, COMPUTER systems
11
Abstract: Parallel-prefix adders offer a highly efficient solution to the binary addition problem and are wellsuited for VLSI implementations. In this paper, a novel framework is introduced, which allows the design of
parallel-prefix Ling adders. The proposed approach saves one-logic level of implementation compared to the
parallel -prefix structures proposed for the traditional definition of carry lookahead equations and reduces the
fanout requirements of the design. Experimental results reveal that the proposed adders achieve delay
reductions of up to 14 percent when compared to the fastest parallel-prefix architectures presented for the
traditional definition of carry equations. [ABSTRACT FROM AUTHOR]
14. Ограничения пропускной способности однонаправленных каналов.
Bounds on the Capacity of the Unidirectional Channels.
By: Tallini, Luca G.. p232-235, 4p;
Ключевые слова: COMPUTER storage devices, ERRORS, INFORMATION technology, INTEGRATED
circuits, RESEARCH, COMPUTER systems
Abstract: In the usual binary symmetric channel, both 1 > 0 and 0 > 1 types of errors can occur. in the binary
asymmetric channel, only 1 > 0 type of errors can occur, whereas, in the unidirectional channel, both 1 > 0 and
0 > 1 types of errors can occur, but, unlike the binary symmetric channel, for any particular transmitted word of
length n, all the errors are of the same type. In general, a symmetric/unidirectional channel is a channel which
shows the behavior of both the symmetric and unidirectional channel. Many practical systems, such as
semiconductor memories and circuits, can be modeled as a unidirectional and/or symmetric/unidirectional
channels. This paper gives the formal definition of these last two channels and shows some interesting simple
bounds on their information capacities. [ABSTRACT FROM AUTHOR]
15. Установление связей, сохраняющих упорядочение переменных ROB DD, может быть
неоптимальным.
Bound-Set Preserving ROB DD Variable Orderings May Not Be Optimum.
By: Teslenko, Maxim; Martinelli, Andres; Dubrova, Elena. p236-237, 2p;
Ключевые слова: ALGEBRA, Boolean, FUNCTIONS, METHODOLOGY, RESEARCH, VARIABLES
(Mathematics), COMPUTER systems
Abstract: This paper reports a result concerning the relation between the best variable orderings of an FIOBDD
Gj and the decomposition structure of the Boolean function f represented by Gj. It was stated in [1] that, if f has
a decomposition of type f(X) = g(h₁(Y₁), h₂(Y₂), … ,
h_k(Y_k)), where (Y₁), i ? (1, 2, … ,k), is a partition of X, then one of the
orderings which keeps the variables within the sets (Y_i) adjacent is a best ordering for Gj. Using a
counterexample, we show that this statement is incorrect. [ABSTRACT FROM AUTHOR]
16. Предотвращение «взрыва» таблицы маршрутизации в пакете углубленной инспекции.
Preventing Session Table Explosion in Packet inspection Computers.
By: Hyogon Kim; Jin-Ho Kim; Inhye Kang; Saewooflg Bahk. p238-240, 3p;
Ключевые слова: COMPUTER networks, COMPUTER security, DATA protection, INTERNET,
MEMORY management (Computer science), SECURITY systems
Abstract: In this paper, we first show that various network attacks can cause fatal inflation of dynamic memory
usage on packet processing computers. Considering Transmission Control Protocol (TCP) is utilized by most of
these attacks as well as legitimate traffic, we propose a parsimonious memory management guideline based on
the design of the TCP and the analysis of real-life Internet traces. In particular, we demonstrate that, for all
practical purposes, one should not allocate memory for an embryonic TCP connection with roughly more than
10 seconds of inactivity. [ABSTRACT FROM AUTHOR]
12
Журнал IEEE Transactions on Information Theory, Jan 2005, Vol. 51 Issue 1,
Труды Института Инженеров по Электротехнике и Электронике (США)
«Теория информации»
Том 51, вып. 1 (Январь 2005 г.)
1. Награды победителям конкурса на лучшие публикации в Трудах Института Инженеров по
Электротехнике и Электронике «Теория информации» 2004 года
2004 IEEE Information Theory Society Paper Award. p2-3, 2p;
By KOETTER, Ral, VARDY, Alexander
Ключевые слова: ASSOCIATIONS, institutions, etc., DECODERS (Electronics), INFORMATION theory,
INFORMATION technology, AWARDS
Abstract: The article presents information about the 2004 IEEE Information Theory Society Paper Award. The
award was given to Ralf Koetter and Alexander Vardy for their paper "Algebraic Soft-Decision Decoding of
Reed-Solomon Codes," which appeared in the IEEE Transactions on Information Theory, vol. 49, pp. 28092825, November 2003. The IEEE Information Theory Society Paper award, consisting of a plaque and an
honorarium, is given annually for an outstanding publication in the field of information theory published
anywhere during the preceding two-year period. Its purpose is to recognize exceptional publications in the field
and to stimulate interest in, and encourage contributions to, the discipline. The award winner Ralf Koetter
received the diploma degree in electrical engineering from the Technical University of Darmstadt, Germany, in
1990 and the Ph.D. degree from Sweden. Another winner Alexander Vardy was born in Moscow in 1963. He
received the B.Sc. degree from the Technion, Haifa, Israel, in 1985 and the Ph.D. degree from the Tel-Aviv
University, Israel, in 1991.
2. Награды победителям конкурса на лучшие общие публикации общества по коммуникациям и
общества по теории информации IEEE за 2004 год.
2004 IEEE Communications Society and Information Theory Society Joint Paper Award.
By CAIRE, Giusepp, SHAMAI, Shlomo
Ключевые слова: ASSOCIATIONS,
INFORMATION theory, AWARDS
institutions,
etc.,
COMMUNICATION,
PUBLICATIONS,
Abstract: The article presents information about the 2004 IEEE Communications Society and Information
Theory Society Joint Paper Award. The award was presented to Giuseppe Caire and Shlomo Shamai for their
paper "On the Achievable Throughput of a Multiantenna Gaussian Broadcast Channel," which appeared in the
IEEE Transactions on Information Theory's July 2003 issue. The award consisting of a plaque and an
honorarium, is given annually for an outstanding paper that appeared in any of the two societies' publications
during the preceding year. The purpose of the award, established in 1999, is to recognize exceptional published
works in research areas of common interest to the two societies. The award winner Guseppe Caire was born in
Torino in Italy in 1965. He received the B.Sc. degree in electrical engineering from the Princeton University in
1992. He did his Ph.D.degree from Politecnino di Torino in 1994. The other winner Shlomo Shamai received
the B.Sc., M.Sc. and Ph.D. degrees in electrical engineering from the Tecnion-Israel Institute of Technology,
Haifa, 1975, 1981 and 1986 respectively.
3. Универсальный дискретный алгоритм шумоподавления: определяемый канал.
Universal Discrete Denoising: Known Channel.
By: Weissman, Tsachy; Ordentlich, Erik; Seroussi, Gadiel; Verdu, Sergio; Weinberger, Marcelo J.. p5-28, 24p
Ключевые слова: ALGEBRA, ALGORITHMS, ARITHMETIC -- Foundations, FORECASTING,
RECONSTRUCTION, SOUND
Abstract: A discrete denoising algorithm estimates the input sequence to a discrete memoryless channel
(DMC) based on the observation of the entire output sequence. For the case in which the DMC is known and
the quality of the reconstruction is evaluated with a given single-letter fidelity criterion, we propose a discrete
denoising algorithm that does not assume knowledge of statistical properties of the input sequence. Yet, the
algorithm is universal in the sense of asymptotically performing as well as the optimum denoiser that knows the
input sequence distribution, which is only assumed to be stationary. Moreover, the algorithm is universal also in
a semi-stochastic setting, in which the input is an individual sequence, and the randomness is due solely to the
13
channel noise. The proposed denoising algorithm is practical, requiring a linear number of register-level
operations and sublinear working storage size relative to the input data length. [ABSTRACT FROM
AUTHOR]
4. О пропускной способности гауссовых релейных каналов (MIMO).
On the Capacity of MIMO Relay Channels.
By: Wang, Bo; Zhang, Junshan; Host-Madsen, Anders. p29-43, 15p;
Ключевые слова: ALGORITHMS, ARITHMETIC -- Foundations, ECONOMICS, Mathematical,
EQUATIONS, MATHEMATICS, NUMERALS, RELAY control systems
Abstract: We study the capacity of multiple-input multiple- output (MIMO) relay channels. We first consider
the Gaussian MIMO relay channel with fixed channel conditions, and derive upper bounds and lower bounds
that can be obtained numerically by convex programming. We present algorithms to compute the bounds. Next,
we generalize the study to the Rayleigh fading case. We find an upper bound and a lower bound on the ergodic
capacity. It is somewhat surprising that the upper bound can meet the lower bound under certain regularity
conditions (not necessarily degradedness), and therefore the capacity can be characterized exactly; previously
this has been proven only for the degraded Gaussian relay channel. We investigate sufficient conditions for
achieving the ergodic capacity; and in particular, for the case where all nodes have the same number of
antennas, the capacity can be achieved under certain signal-to-noise ratio (SNR) conditions. Numerical results
are also provided to illustrate the bounds on the ergodic capacity of the MIMO relay channel over Rayleigh
fading. Finally, we present a potential application of the MIMO relay channel for cooperative communications
in ad hoc networks. [ABSTRACT FROM AUTHOR]
5. Классическая пропускная способность и квантовая пропускная способность квантового
канала.
The Private Classical Capacity and Quantum Capacity of a Quantum Channel.
By: Devetak, Igor. p44-55, 12p;
Ключевые слова: ALGEBRA, ARITHMETIC, MATHEMATICIANS, MATHEMATICS, QUANTUM
theory, STATISTICS
Abstract: A formula for the capacity of a quantum channel for transmitting private classical information is
derived. This is shown to be equal to the capacity of the channel for generating a secret key, and neither
capacity is enhanced by forward public classical communication. Motivated by the work of Schumacher and
Westmoreland on quantum privacy and quantum coherence, parallels between private classical information and
quantum information are exploited to obtain an expression for the capacity of a quantum channel for generating
pure bipartite entanglement. The latter implies a new proof of the quantum channel coding theorem and a
simple proof of the converse. The coherent information plays a role in all of the above mentioned capacities.
[ABSTRACT FROM AUTHOR]
6. Дистанционная подготовка квантуемых состояний.
Remote Preparation of Quantum States.
By: Bennett, Charles H.; Hayden, Patrick; Leung, Debbie W.; Shor, Peter W.; Winter, Andreas. p56-74, 19p;
Ключевые слова: DATA compression (Telecommunication), DATA transmission systems, DIGITAL
communications, MATHEMATICS, QUANTUM theory, SPECIFICATIONS
Abstract: Remote state preparation is the variant of quantum state teleportation in which the sender knows the
quantum state to be communicated. The original paper introducing teleportation established minimal
requirements for classical communication and entanglement but the corresponding limits for remote state
preparation have remained unknown until now: previous work has shown, however, that it not only requires
less classical communication but also gives rise to a tradeoff between these two resources in the appropriate
setting. We discuss this problem from first principles, including the various chokes one may follow in the
definitions of the actual resources. Our main result is a general method of remote state preparation for arbitrary
states of many qubits, at a cost of 1 bit of classical communication and 1 bit of entanglement per qubit sent. In
this "universal" formulation, these ebit and chit requirements are shown to be simultaneously optimal by
exhibiting a dichotomy. Our protocol then yields the exact tradeoff curve for memoryless sources of pure states
14
(including the case of incomplete knowledge of the ensemble probabilities), based on the recently established
quantum-classical tradeoff for visible quantum data compression. A variation of that method allows us to solve
the even more general problem of preparing entangled states between sender and receiver (i.e., purifications of
mixed state ensembles). The paper includes an extensive discussion of our results, including the impact of the
choice of model on the resources, the topic of obliviousness, and an application to private quantum channels
and quantum data hiding. [ABSTRACT FROM AUTHOR]
7. О существовании катализаторов преобразования квантовых состояний.
The Existence of Quantum Entanglement Catalysts.
By: Xiaoming Sun; Runyao Duan; Mingsheng Ying. p75-80, 6p;
Ключевые слова: ALGEBRA, ALGORITHMS, ARITHMETIC -- Foundations, CATALYSTS, CHEMICAL
inhibitors, MATHEMATICS, QUANTUM theory
Abstract: Without additional resources, it is often impossible to transform one entangled quantum state into
another with local quantum operations and classical communication. Jonathan and Plenio (Phys. Rev. Left., vol.
83, p. 3566, 1999) presented an interesting example showing that the presence of another state, called a catalyst,
enables such a transformation without changing the catalyst. They also pointed out that in general it is very hard
to find an analytical condition under which a catalyst exists. In this paper, we study the existence of catalysts
for two incomparable quantum states. For the simplest case of 2 2 catalysts for transformations from one 4  4
state to another, a necessary and sufficient condition for existence is found. For the general case, we give an
efficient polynomial time algorithm to decide whether a k  k catalyst exists for two n  n incomparable states,
where k is treated as a constant. [ABSTRACT FROM AUTHOR]
8. Стохастический анализ турбо-декодирования.
Stochastic Analysis of Turbo Decoding.
By: Minyue Fu. p81-100, 20p
Ключевые слова: CALCULUS, MATHEMATICAL analysis, PROGRAMMING languages (Electronic
computers), RANDOM operators, STOCHASTIC analysis, TURBO (Computer program language)
Abstract: This paper proposes a stochastic framework for dynamic modeling and analysis of turbo decoding.
By modeling the input and output signals of a turbo decoder as random processes, we prove that these signals
become ergodic when the block size of the code becomes very large. This basic result allows us to easily model
and compute the statistics of the signals in a turbo decoder. Using the ergodicity result and the fact that a sum of
lognormal distributions is well approximated using a lognormal distribution, we show that the input-output
signals in a turbo decoder, when ex- pressed using log-likelihood ratios (LLR5), are well approximated using
Gaussian distributions. Combining the two results above, we can model a turbo decoder using two input
parameters and two output parameters (corresponding to the means and variances of the input and output
signals). Using this model, we are able to re- veal the whole dynamics of a decoding process. We have
discovered that a typical decoding process is much more intricate than previously known, involving two regions
of attraction, several fixed points, and a stable equilibrium manifold at which all decoding trajectories converge.
Some applications of the stochastic framework are also discussed, including a fast decoding scheme.
[ABSTRACT FROM AUTHOR]
9. Перемеживатели турбо-кодов, использующие перестановочные полиномы в целочисленных
кольцах.
Interleavers for Turbo Codes Using Permutation Polynomials Over Integer Rings.
By: Jing Sun; Takeshita, Oscar Y.. p101-119, 19p;
Ключевые слова: COMBINATORIAL analysis, GROUP theory, MATHEMATICS, PROGRAMMING
(Mathematics), PROGRAMMING languages (Electronic computers), TURBO (Computer program language)
Abstract: In this paper, a class of deterministic interleavers for turbo codes (TCs) based on permutation
Polynomials over Z_N is introduced. The main characteristic of this class of interleavers is that they
can be algebraically designed to 'fit a given component code. Moreover, since the interleaver can be generated
by a few simple computations, storage of the interleayer tables can be avoided. By using the permutation
polynomial-based interleavers, the design of the interleavers reduces to the selection of the coefficients of the
15
polynomials. it is observed that the performance of the TCs using these permutation polynomial-based
interleavers is usually dominated by a subset of input weight 2m error events. The minimum distance and its
multiplicity (or the first few spectrum lines) of this subset are used as design criterion to select good
permutation polynomials. A simple method to enumerate these error events for small m is presented. Searches
for good interleavers are performed. The decoding performance of these interleavers is close to S-random
interleavers for long frame sizes. For short frame sizes, the new interleavers outs perform S-random
interleavers. [ABSTRACT FROM AUTHOR]
10. Декодирование, основанное на верификации, в пакетных кодах проверки четности низкой
плотности
Verification-Based Decoding for Packet-Based Low-Density Parity-Check Codes.
By: Luby, Michael G.; Mitzenmacher, Michael. p120-127, 8p
Ключевые слова: ALGEBRA, CIPHERS, LOGIC, MATHEMATICS, PACKET switching (Data
transmission), PROGRAMMING (Mathematics), DECODERS & decoding
Abstract: We introduce and analyze verification-based decoding for low-density parity-check (LDPC) codes,
an approach specifically designed to manipulate data in packet-sized units. Verification-based decoding
requires only linear time for both encoding and decoding and succeeds with high probability under random
errors. We describe how to utilize code scrambling to extend our results to channels with errors controlled by
an oblivious adversary. [ABSTRACT FROM AUTHOR]
11. Совместимость поддержки векторных машин и остальных регуляризованных сортировщиков
ядра.
Consistency of Support Vector Machines and Other Regularized Kernel Classifiers.
By: Steinwart, Ingo. p128-142, 15p;
Ключевые слова: ALGEBRAS, Linear, CLASSIFICATION, MATHEMATICS, STATISTICS, VECTOR
algebra, VECTOR analysis
Abstract: It is shown that various classifiers that are based on minimization of a regularized risk are
universally consistent, i.e., they can asymptotically learn in every classification task. The role of the loss
functions used in these algorithms is considered in detail. As an application of our general framework, several
types of support vector machines (SVMs) as well as regularization networks are treated. Our methods combine
techniques from stochastics, approximation theory, and functional analysis. [ABSTRACT FROM AUTHOR]
12. Условная важность выборочных оценок.
Conditional Importance Sampling Estimators.
By: Bucklew, James A.. p143-153, 11p;
Ключевые слова: ARITHMETIC, MATHEMATICAL statistics,
SAMPLING (Statistics), STATISTICS
MATHEMATICS,
SAMPLING,
Abstract: We give a unified presentation of the conditional importance sampling estimators. We show that they
are always better than their noncoditional counterparts. We then present the large diviation theory associated
with these estimators. In particular, we give conditional simulation distributions that are optimal in the sense
that they are efficient. Interestingly enough, these distributions will not in general be the usual exponential
shifts. We give examples showing how to use the theory developed. [ABSTRACT FROM AUTHOR]
13. Равно-диагональная декомпозиция и ее применение в проектировании устройства
предварительного кодирования при последовательно-компенсационном детектировании.
Equal-Diagonal QR Decomposition and its Application to Precoder Design for Successive-Cancellation
Detection.
By: Jian-Kang Zhang; Aleksandar Kavcic; Kon Max Wong. p154-172, 19p;
Ключевые слова: DECOMPOSITION (Mathematics), DETECTORS, MATHEMATICS, MULTIPLEXING,
ORTHOGONAL decompositions, PROBABILITIES
16
Abstract: In multiple-input multiple-output (MIMO) multi- user detection theory, the QR decomposition of the
channel matrix H can be used to form the back-cancellation detector. In this paper, we propose an optimal QR
decomposition, which we call the equal-diagonal QR decomposition, or briefly the QRS decomposition. We
apply the decomposition to precoded successive-cancellation detection, where we assume that both the
transmitter and the receiver have perfect channel knowledge. We show that, for any channel matrix H, there
exists a unitary precoder matrix S, such that HS = QR, where the nonzero diagonal entries of the upper
triangular matrix H in the QR decomposition of HR are all equal to each other. The precoder and the resulting
successive-cancellation detector have the following properties. a) The minimum Euclidean distance between
two signal points at the channel output is equal to the minimum Euclidean distance between two constellation
points at the precoder input up to a multiplicative factor that equals the diagonal entry in the R-factor. b) The
superchannel HS naturally exhibits an optimally ordered column permutation, i.e., the optimal detection order
for the vertical Bell Labs layered space-time (V-BLAST) detector is the natural order. c) The precoder S
minimizes the block error probability of the QR successive cancellation detector. d) A lower and an upper
bound for the free distance at the channel output is expressible in terms Of the diagonal entries of the H-factor
in the QR decomposition of a channel matrix. e) The precoder S maximizes, the lower bound of the channel's
free distance subject to a power constraint. 1) For the optimal precoder 5, the performance of the QR detector is
asymptotically (at large signal-to-noise ratios (SNRs)) equivalent to that of the maximum-likelihood detector
(MLD) that uses the same precoder. Further, in this paper we consider two multiplexing schemes: time-division
multiple access (TDMA) and orthogonal frequency-division... [ABSTRACT FROM AUTHOR]
14. Информационно-теоретический подход к определению канонических приемников с
решающей обратной связью в гауссовых каналах.
An Information-Theoretic Framework for Deriving Canonical Decision-Feedback Receivers in Gaussian
Channels.
By: Guess, Tommy; Varanasi, Mahesh K.. p173-187, 15p;
Ключевые слова: DISTRIBUTION (Probability theory), GAUSSIAN measures, GAUSSIAN processes,
INFORMATION theory, MATHEMATICS, MEASURE theory
Abstract: A framework is presented that allows a number of known results relating feedback equalization,
linear prediction, and mutual information to be easily understood. A lossless, additive decomposition of mutual
information in a general class of Gaussian channels is introduced and shown to produce an informationpreserving canonical decision -feedback receiver. The approach is applied to intersymbol interference (ISI)
channels to derive the well-known minimum mean-square error (MMSE) decision-feedback equalizer (DFE).
When applied to the synchronous code-division multiple-access (CDMA) channel, the result is the MMSE (or
signal-to-interference ratio (SIR) maximizing) decision-feedback detector, which is shown to achieve the
channel sum-capacity at the vertices of the capacity region. Finally, in the case of the asynchronous CDMA
channel we are able to give new connections between information theory, decision-feedback receivers, and
structured factorizations of multivariate spectra. [ABSTRACT FROM AUTHOR]
15. Проектирование структурированного тесного кадрирования с помощью метода переменных
проекций.
Designing Structured Tight Frames Via an Alternating Projection Method.
By: Tropp, Joel A.; Dhillon, Inderjit S.; Heath Jr., Robert W.; Strohmer, Thomas. p188-209, 22p;
Ключевые слова: ALGORITHMS, GEOMETRY, Descriptive, MATHEMATICS, PROJECTION,
SPECIFICATIONS, DECODERS & decoding
Abstract: Tight frames, also known as general Welch-bound-equality sequences, generalize orthonormal
systems. Numerous applications-including communications, coding, and sparse approximation-require finitedimensional tight frames that possess additional structural properties. This paper proposes an alternating
projection method that is versatile enough to solve a huge class of inverse eigenvalue problems (IEPs), which
includes the frame design problem. To apply this method, one needs only to solve a matrix nearness problem
that arises naturally from the design specifications. Therefore, it is the fast and easy to develop versions of the
algorithm that target new design problems. Alternating projection will often succeed even if algebraic
constructions are unavailable. To demonstrate that alternating projection is an effective tool for frame design,
the paper studies some important structural properties in detail. First, it addresses the most basic design
17
problem: constructing tight frames with prescribed vector norms. Then, it discusses equiangular tight frames,
which are natural dictionaries for sparse approximation. Finally, it examines tight frames whose individual
vectors have low peak-to-average-power ratio (PAR), which is a valuable property for code-division multipleaccess (CDMA) applications. Numerical experiments show that the proposed algorithm succeeds in each of
these three cases. The appendices investigate the convergence properties of the algorithm. [ABSTRACT FROM
AUTHOR]
16. Принципы кодирования для обеспечения отказоустойчивости линейных динамических
систем.
Coding Approaches to Fault Tolerance in Linear Dynamic Systems.
By: Hadjicostis, Christoforos N.; Verghese, George C.. p210-228, 19p;
Ключевые слова: ALGEBRAS, Linear, DIFFERENTIAL equations, Linear, LINEAR systems,
MATHEMATICS, SYSTEM theory, DECODERS & decoding
Abstract: This paper discusses fault tolerance in discrete-time dynamic systems, such as finite-state controllers
or computer simulations, with focus on the use of coding techniques to efficiently provide fault tolerance to
linear finite-state machines (LFSMs). Unlike traditional fault tolerance schemes, which rely heavily-particularly
for dynamic systems operating over extended time horizons-on the assumption that the error-correcting
mechanism is fault free, we are interested in the case when all components of the implementation are fault
prone. The paper starts with a paradigmatic fault tolerance scheme that systematically adds redundancy into a
discrete-time dynamic system in a way that achieves tolerance to transient faults in both the state transition and
the error-correcting mechanisms. By combining this methodology with low-complexity error-correcting coding,
we then obtain an efficient way of providing fault tolerance to k identical unreliable LFSMs that operate in
parallel on distinct input sequences. The overall construction requires only a constant amount of redundant
hardware per machine (but sufficiently large k) to achieve an arbitrarily small probability of overall failure for
any prespecified (finite) lime interval, leading in this way to a lower bound on the computational capacity of
unreliable LFSMs. [ABSTRACT FROM AUTHOR]
17. Коды для пространственно-частотного канала, характеризуемого полной загрузкой и полным
разнесением частот, при оптимальном кодировании информации.
Full-Rate Full-Diversity Space-Frequency Codes With Optimum Coding Advantage.
By: Weifeng Su; Safar, Zoltan; Ray Liu, K. J.. p229-249, 21p;
Ключевые слова: CODING theory, DIFFERENTIAL equations,
MATHEMATICS, SOUND -- Transmission, DECODERS & decoding
Linear,
ELECTRIC
lines,
Abstract: In this paper, a general space-frequency (SF) block code structure is proposed that can guarantee
full-rate (one channel symbol per subcarrier) and full-diversity transmission in multiple-input multiple-outputorthogon frequency-division multiplexing (MIMO-OFDM) systems. The proposed method can be used to
construct SF codes for an arbitrary number of transmit antennas, any memoryless modulation and arbitrary
power-delay profiles. Moreover, assuming that the power-delay profile is known at the transmitter, we devise
an interleaving method to maximize the overall performance of the code. We show that the diversity product
can be decomposed as the product of the "intrinsic" diversity product, which depends only on the used signal
constellation and the code design, and the "extrinsic" diversity product, which depends only on the applied
interleaving method and the power delay profile of the channel. Based on this decomposition, we pro- pose an
interleaving strategy to maximize the "extrinsic" diversity product. Extensive simulation results show that the
proposed SF codes outperform the previously existing codes by about 3-5 dB, and that the proposed
interleaving method results in about 1-3-dR performance improvement compared to random interleaving.
[ABSTRACT FROM AUTHOR]
18. Границы пространственного распределения в кодах определенной разрядности.
Bounds on Distance Distributions in Codes of Known Size.
By: Ashikhmin, Alexei E.; Cohen, Gerard D.; Krivelevich, Michael; Litsyn, Simon N.. p250-258, 9p;
Ключевые слова: CODING theory, ELECTRIC lines, MATHEMATICAL analysis, MATHEMATICAL
statistics, SOUND -- Transmission, TIME-series analysis, DECODERS & decoding
18
Abstract: We treat the problem of bounding components of the possible distance distributions of codes given
the knowledge of their size and possibly minimum distance. Using the Beckner inequality from harmonic
analysis, we derive upper bounds on distance distribution components which are sometimes better than earlier
ones due to Ashikhmin, Barg, and Litsyn. We use an alternative approach to derive upper bounds on distance
distributions in linear codes. As an application of the suggested estimates we get an upper bound on the
undetected error probability for an arbitrary code of given size. We also use the new bounds to derive better
upper estimates on the covering radius, as well as a lower bound on the error-probability threshold, as a
function of the code's size and minimum distance. [ABSTRACT FROM AUTHOR]
19. Геометрические коды Гоппа, соответствующие ограничению Гильберта-Варшамова.
Goppa Geometric Codes Achieving the Gilbert -- Varshamov Bound.
By: Chaoping Xing. p259-264, 6p;
Ключевые слова: GEOMETRICAL constructions, GEOMETRY, MATHEMATICS, GEOMETRIC
dissections, ANGLES (Geometry), DECODERS & decoding
Abstract: Based on 8 -zeta-functions of curves over finite fields, we show that Goppa geometry codes achieve
the q-ary Gilbert- Varshamoy bound for all prime powers q (including q = 2).
[ABSTRACT FROM AUTHOR] 20.
20. Уточнение границ вероятности ошибки в слове в кодах RA(2) при декодировании, основанном
на методе линейного программирования.
Improved Bounds on the Word Error Probability of RA(2) Codes With Linear-Programming-Based Decoding.
By: Halabi, Nissim; Even, Guy. p265-280, 16p;
Ключевые слова: ALGORITHMS, CIPHERS, COMPLEXES, GEOMETRY, Algebraic, LINEAR models
(Statistics), MATHEMATICS, DECODERS & decoding
Abstract: This paper deals with the linear-programming-based decoding algorithm of Feldman and Karger for
repeat-accumulate "turbo-like" codes. We present a new structural characterization that captures the event that
decoding fails. Based on this structural characterization, we develop polynomial algorithms that, given an RA
(2) code, compute upper and lower bounds on the word error probability P_w for the binarysymmetric and the additive white Gaussian noise (AWGN) channels. Our experiments with an implementation
of these algorithms for bounding P_w demonstrate in many interesting cases an improvement in the
upper bound on the word error probability by a factor of over 1000 compared to the bounds by Feldman et al..
The experiments also indicate that the improvement in upper bound increases as the codeword length increase
and the channel noise decrease. The computed lower bounds on the word error probability in our experiments
are roughly ten times smaller than the upper bound. [ABSTRACT FROM AUTHOR]
21. Р-адические величины весов в Абелевых кодах выше Z_p^d.
P-Adic Valuation of Weights in Abelian Codes Over Z_p^d.
By: Katz, Daniel J.. p281-305, 25p;
Ключевые слова: APPROXIMATION theory, LINEAR operators, MATHEMATICS, MENSURATION,
OPERATOR theory, WEIGHTS & measures
Abstract: Counting polynomial techniques introduced by Wilson are used to provide analogs of a theorem of
McEliece. McEliece's original theorem relates the greatest power of p dividing the Hamming weights of words
in cyclic codes over GF (p) to the length of the smallest unity-product sequence of nonzeroes of the code.
Calderbank, Li, and Poonen presented analogs for cyclic codes over Z_2^d using
various weight functions (Hamming, Lee, and Eudidean weight as well as count of occurrences of a particular
symbol). Some of these results were strengthened by Wilson, who also considered the alphabet
Z_p^d for p an arbitrary prime. These previous results, new strengthened versions, and
generalizations are proved here in a unified and comprehensive fashion for the larger class of Abelian codes
over Z_p^d with p any prime. For Abelian codes over Z₄, combinatorial
methods for use with counting polynomials are developed. These show that the analogs of McEliece's theorem
obtained by Wilson (for Hamming weight, Lee weight, and symbol counts) and the analog obtained here for
19
Euclidean weight are sharp in the sense that they give the maximum power of 2 that divides the weights of all
the codewords whose Fourier transforms have a specified support. [ABSTRACT FROM AUTHOR]
22. Обнаружение и оценка ошибочных сложных случайных сигналов.
Detection and Estimation of Improper Complex Random Signals.
By: Schreier, Peter J.; Scharf, Louis L.; Mullis, Clifford T.. p306-312, 7p;
Ключевые слова: ALGEBRA, Abstract, COMMUNICATION, ESTIMATION theory, MATHEMATICAL
analysis, MATHEMATICS, SIGNALS & signaling
Abstract: Nonstationary complex random signals are in general improper (not circularly symmetric), which
means that their complementary covariance is nonzero. Since the Karhunen-Loeve (K-L) expansion in its
known form is only valid for proper processes, we derive the improper version of this expansion. it produces
two sets of eigenvalues and improper observable coordinates. We then use the K-L expansion to solve the
problems of detection and estimation of improper complex random signal in additive white Gaussian noise. We
derive a general result comparing the performance of conventional processing, which ignores complementary
covariances, with processing that takes these into account in particular, for the detection and estimation
problems considered, we find that the performance gain, as measured by deflection and mean-squared error
(MSE), respectively, can be as large as a factor of 2 In a communications example, we show how this finding
generalizes the result that coherent processing enjoys a 3-dB gain over noncoherent processing. [ABSTRACT
FROM AUTHOR]
23. Об адаптации минимального расхождения к заданным маргинальным значениям в
дискретном двумерном распределении.
On Minimum Divergence Adaptation of Discrete Bivariate Distributions to Given Marginals.
By: Vajda, Igor; van der Meulen, Edward C.. p313-320, 8p;
Ключевые слова: DISTRIBUTION (Probability theory), LOGIC, MATHEMATICS, STATISTICS,
DIFFERENCES
Abstract: This correspondence considers the class P of discrete bivariate distributions p with marginals a(p),
b(p) and the subclass P_a,b  P of distribution with given marginals a and b. For an arbitrary q  P
we study the distributions &ptilde;  P_a,b minimizing on P_a,b various -divergences
D_?(p,q) for convex  with finite (0). [ABSTRACT FROM AUTHOR]
24. Об обратной связи и классической пропускной способности зашумленного квантового канала.
On Feedback and the Classical Capacity of a Noisy Quantum Channel.
By: Bowen, Garry; Nagarajan, Rajagopal. p320-324, 5p;
Ключевые слова: CHANNELS (Hydraulic engineering), COMMUNICATION, MATHEMATICS,
QUANTUM theory, APPROACH channels (Hydraulic engineering)
Abstract: In Shannon information theory, the capacity of a memoryless communication channel cannot be
increased by the use of feedback from receiver to sender. In this correspondence, the use of classical feedback
is shown to provide no increase in the unassisted classical capacity of a memoryless quantum channel when
feedback is used across nonentangled input states, or when the channel is an entanglement-breaking channel.
This gives a generalization of the Shannon theory for certain classes of feedback protocols when transmitting
through noisy quantum communication channels. [ABSTRACT FROM AUTHOR]
25. Алгебраическая идентификация в оптимальных неортогональных комплексных
пространственно-временных блочных кодах 44 с использованием тензорного произведения на
кватернионах.
Algebraic Identification for Optimal Nonorthogonality 4  4 Complex Space-Time Block Codes Using Tensor
Product on Quaternions.
By: Ming-Yang Chen; Hua-Chieh Li; Soo-Chang Pei. p324-330, 7p;
Ключевые слова: ALGEBRA, ALGEBRAIC fields, CURVES, MATHEMATICS, QUATERNIONS,
VECTOR analysis
20
Abstract: The design potential of using quaternionic numbers to identify a 4  4 real orthogonal space-time
block code has been exploited in various communication articles. Although it has been shown that orthogonal
codes in full-rate exist only for 2 Tx-antennas in complex constellations, a series of complex quasi-orthogonal
codes for 4 Tx-antennas is still proposed to have good performance recently. This quasi-orthogonal scheme
enables the codes to reach the optimal nonorthogonality, which can be measured by taking the expectation over
all transmit signals of the ratios between the powers of the off-diagonal and diagonal components. This
correspondence extends the quaternionic identification to the above encoding methods. Based upon tensor
product for giving the quaternionic space a linear extension, a complete necessary and sufficient condition for
identifying any given complex quasi-orthogonal code with the extended space is generalized by considering
every possible two-dimensional R-algebra. [ABSTRACT FROM AUTHOR]
26. Звездная пространственная инвариантность ортогональных пространственно-временных
блочных кодов.
Constellation Space Invariance of Orthogonal Space --Time Block Codes.
By: Gharavi-Alkhansari, Mohammad; Gershman, Alex B.. p331-334, 4p;
Ключевые слова: CALCULUS of variations, CODING theory, COMBINATORIAL designs &
configurations, CURVES, Orthogonal, FUNCTIONAL equations, MATHEMATICS
Abstract: In this correspondence, we prove an interesting property of orthogonal space-time block codes
(OSTBCs). For flat block-fading channels, it is shown that the internal structure of the vector space of the input
constellation remains invariant to the effects of both the OSTBC and the channel except for certain scaling
factors. This property sheds light on the mechanism of maximum-likelihood (ML) decoding of OSTBCs and, in
particular, provides an alternative explanation of why optimal decoding can be reduced to symbol-by-symbol
decoding. New simple expressions for the ML decoder are obtained which clarify its intrinsic structure.
[ABSTRACT FROM AUTHOR]
27. Использование управляемого поиска экстремума для геометрического построения множеств
треугольников разностей.
Using Directed Hill-Climbing for the Construction of Difference Triangle Sets.
By: Koubi, Sharon; Mata-Montero, Mannque; Shalaby, Nabil. p335-339, 5p;
Ключевые слова: ALGEBRA, ALGORITHMS, GEOMETRY, Plane, MATHEMATICS, TRIANGLE,
SHAPES
Abstract: This correspondence describes the use of the directed hill-climbing algorithm for finding improved
upper bounds of difference triangle sets. [ABSTRACT FROM AUTHOR]
28. Улучшенное построение нелинейных эластичных узлов замен (S-Boxes).
Improved Construction of Nonlinear Resilient S-Boxes.
By: Gupta, Kishan Chand; Sarkar, Palash. p339-348, 10p;
Ключевые слова: LGEBRA, BOXES, CONTAINERS, MATHEMATICS, NONLINEAR control theory,
TRIANGLE, SHAPES
Abstract: We provide two new construction methods for nonlinear resilient functions. The first method is a
simple modification of a construction due to Zhang and Zheng and constructs n-input, m-output resilient Sboxes with degree d > m. We prove by an application of the Griesnier bound for linear error-correcting codes
that the modified Zhang-Zheng construction is superior to the previous method of Cheon in Crypto 2001. Our
second construction uses a sharpened version of the Maiorana-McFar- land technique to construct nonlinear
resilient functions. The nonlinearity obtained by our second construction is better than previously known
construction methods. [ABSTRACT FROM AUTHOR]
29. Максимальная квадратичная корреляция, общий размер и общая асимптотическая
эффективность минимальной общей квадратичной корреляции множеств бинарных сигнатур.
The Maximum Squared Correlation, Sum Capacity, and Total Asymptotic Efficiency of Minimum TotalSquared-Correlation Binary Signature Sets.
By: Karystinos, George N.; Pados, Dimitris A.. p348-355, 8p;
21
Ключевые слова: INARY system (Mathematics), CORRELATION (Statistics), MATHEMATICAL
statistics, MATHEMATICS, NUMERATION, STATISTICS
Abstract: The total squared correlation (TSC), maximum squared correlation (MSC), sum capacity (C/sum),
and total asymptotic efficiency (TAE) of underloaded signature sets, as well as the TSC and C_sum
of over- loaded signature sets are metrics that are optimized simultaneously over the real/complex field. In this
present work, closed-form expressions are derived for the MSC, C_sum, and TAE of minimumTSC binary signature sets. The expressions disprove the general equivalence of these performance metrics over
the binary field and establish conditions on the number of signatures and signature length under which
simultaneous optimization can or cannot be possible. The sum-capacity loss of the recently designed minimumTSC binary sets is found to be rather negligible in comparison with minimum-TSC real/complex-valued
(Welch-bound-equality) sets. [ABSTRACT FROM AUTHOR]
30. Контр- пример к открытой проблеме минимального запаздывания в ортогональной
конструкции с наибольшей скоростью передачи данных.
A Counterexample for the Open Problem on the Minimal Delays of Orthogonal Designs With Maximal Rates.
By: Haibin Kan; Hong Shen. p355-359, 5p;
Ключевые слова: CIRCLE, COMBINATORIAL designs & configurations, CURVES, Orthogonal,
GEOMETRY, MATHEMATICS, TRIANGLE
Abstract: X. Liang systematically investigated orthogonal designs with maximal rates, gave the. maximal rates
of complex orthogonal designs and a concrete construction procedure for complex orthogonal designs with the
maximal rates. He also posed an open problem on the minimal decoding delays of complex orthogonal designs
with maximal rates, and proved that the problem is correct for less than or equal to six transmit antennas. In this
correspondence, we give a counterexample for the open problem for n = 8 and prove that the minimal delay for
complex orthogonal designs with eight columns is 56. Hence, we give a negative answer for the open problem.
[ABSTRACT FROM AUTHOR]
31. Зависимое от расстояния отображение двоичных векторов в перестановки.
Distance-Increasing Mappings From Binary Vectors to Permutations.
By: Jen-Chun Chang. p359-363, 5p;
Ключевые слова: BINARY system (Mathematics), FORMS, Binary, FUNCTIONS, Continuous,
MAPPINGS (Mathematics), MATHEMATICS, PERMUTATIONS, TRANSFORMATIONS (Mathematics)
Abstract: Mappings from the set of binary vectors of a fixed length to the set of permutations of the same
length that strictly increase Hamming distances except when that is obviously not possible are useful for the
construction of permutation codes. In this correspondence, we propose recursive and explicit constructions of
such mappings. Some comparisons show that the new mappings have better distance expansion distributions
than other known distance-preserving mappings (DPMs). We also give some examples to illustrate the
applications of these mappings to permutation arrays (PAs). [ABSTRACT FROM AUTHOR]
32. Экспоненциальная ошибка достижимости в пуассоновском широковещательном канале с
неполными множествами сообщений.
Attainable Error Exponents for the Poisson Broadcast Channel With Degraded Message Sets.
By: Sokolovsky, Alexander; Bross, Shraga I.. p364-374, 11p;
Ключевые слова: ROADCASTING, CODING theory, DATA compression (Computer science), DATA
transmission systems, DIGITAL communications, COMPUTER programming
Abstract: The Poisson broadcast channel with degraded message sets models a bandwidth unlimited optical
broadcast network over which a sender communicates a common message to a pair of terminals and a private
message to just one of them. The capacity region for this communication model is determined by the KornerMarton result, which in the Poisson regime Is shown to coincide with the capacity region of the degraded
broadcast channel. We present explicit code construction and practical decoding rules which attain the
corresponding capacity region, while attempting to maximize the attainable error exponents at the two distinct
terminals. This is accomplished by computing the error exponents attainable by the suggested decoding rules,
22
using the technique developed by Wyner and further extended by Bross and Shamai. [ABSTRACT FROM
AUTHOR]
33. Логарифмическая выпуклость минимальной общей мощности в системах коллективного
доступа с кодовым разделением каналов (CDMA) при фиксированном значении критерия
качества обслуживания.
Log-Convexity of the Minimum Total Power in CDMA Systems With Certain Quality-of-Service Guaranteed.
By: Boche, Holger; Stanczak, S&lslash;awomir. p374-381, 8p;
Ключевые слова: HANNELS (Hydraulic engineering), CODING theory, DATA compression (Computer
science), DATA transmission systems, DIGITAL communications, SPECIFICATION, WAVE mechanics
Abstract: In this correspondence, we consider a code-division multiple- access (CDMA) channel with a linear
receiver structure whose inputs are subject to a total power constraint. Each user is required to satisfy a certain
quality-of-service (QoS) requirement expressed, for instance, in terms of data rate or delay. The set of all
feasible QoS requirements is called the feasibility region. It is shown that if the signal-to-interference ratio
(SIR) at the output of each linear receiver is a bijective and log-convex function of the QoS parameter of
interest, the minimum total power needed to satisfy the QoS requirements is a jointly log-convex function of the
QoS parameters. Furthermore, in two special cases of practical Interest, we show that the minimum total power
is strictly log-convex. These results imply that the corresponding feasibility regions are convex sets. The
convexity property is a key ingredient in the development of access control strategies for wireless
communications systems. [ABSTRACT FROM AUTHOR]
34. Коэффициент производительности и потерь кодирования источника.
Coefficient Rate and Lossy Source Coding.
By: Wenye Yang; Gibson, Jerry D.; Tao He. p381-386, 6p;
Ключевые слова: BINOMIAL coefficients, CHANNELS (Hydraulic engineering), CODING theory, DATA
compression (Computer science), DATA transmission systems, DIGITAL communications, WAVE mechanics
Abstract: Campbell derived and defined a quantity called the coefficient rate of a random process that involves
the process spectral entropy. In this correspondence, his interpretation is substantiated with two new
derivations. One derivation tightens the connection to source bandwidth, while the second derivation implies a
specific approach to adaptive coefficient selection in realization-adaptive approaches to compression. After a
discussion on the role the coefficient rate plays in adaptive source coding, a quantity called Campbell
bandwidth is defined based on its connection to source bandwidth and Is contrasted with Fourier bandwidth and
Shannon band- width. The connection between coefficient rate and reverse water-filling from rate distortion
theory is also demonstrated. [ABSTRACT FROM AUTHOR]
35. Регулярные и нерегулярные прогрессирующие с прирастающими ребрами графы Таннера.
Regular and Irregular Progressive Edge-Growth Tanner Graphs.
By: Xiao-Yu Hu; Eleftheriou, Evangelos; Arnold, Dieter M.. p386-398, 13p;
Ключевые слова: LGEBRA, ALGORITHMS, ARITHMETIC, GRAPH theory, MATHEMATICS, GRAPH
algorithms
Abstract: We propose a general method for constructing Tanner graphs having a large girth by establishing
edges or connections between symbol and check nodes in an edge-by-edge manner, called progressive edgegrowth (PEG) algorithm. Lower bounds on the girth of PEG Tanner graphs and on the minimum distance of the
resulting low-density parity-check (LDPC) codes are derived in terms of parameters of the graphs. Simple
variations of the PEG algorithm can also be applied to generate linear-time encodeable LDPC codes. Regular
and irregular LDPC codes using PEG Tanner graphs and allowing symbol nodes to take values over GF(q) (q >
2) are investigated. Simulation results show that the PEG algorithm is a powerful algorithm to generate good
short-block-length LDPC codes. [ABSTRACT FROM AUTHOR]
36. Об эквивалентности двух ключевых уравнений Вэлча-Берлекакампа и их оценщиках ошибок.
On the Equivalence of Two Welch -- Berlekamp Key Equations and Their Error Evaluators.
By: Moon, Todd K.; Gunther, Jacob H.. p399-401, 3p;
23
Ключевые слова: ALGEBRA, ALGEBRA -- Graphic methods, ALGORITHMS, CIPHERS, EQUATIONS,
EQUATIONS -- Numerical solutions, MATHEMATICS
Abstract: We present two lemmas relating polynomials occurring in the derivations of the Welch-Berlekamp
(WB) key equation for Reed- Solomon codes. The lemma provides the connection between the conventional
Welch-Berlekamp form of the key equation and the nulispace-based derivation of Dabiri and Blake. The second
lemma allows the error values for the Dahiri Blake formulation to be computed based on the error values for the
Welch-Berlekamp form. [ABSTRACT FROM AUTHOR]
37. О весовых энумераторах дуадиковых и квадратичных кодов в остатках.
On the Weight Enumerators of Duadic and Quadratic Residue Codes.
Carmen-Simona; Wassermann, Alfred. p402-407, 6p;
By: Gabont, Philippe; Nedeloaia,
Ключевые слова: ALGEBRA, ALGEBRA -- Graphic methods, ALGORITHMS, CIPHERS, EQUATIONS - Numerical solutions, MATHEMATICS
Abstract: In this correspondence, we compute the weight enumerators of various quadratic residue codes over
F₂ and F₃, together with certain codes of related families like the duadic and the
quadratic double circulant codes. We use a parallel algorithm to find the number of codewords of a given (not
too high) weight, from which we deduce by usual classical methods for self-dual and formally self-dual codes
over F₂ and F₃ their associated, previously unknown, weight enumerators. We
compute weight enumerators for lengths as high as 152 for binary codes and 96 for ternary codes. [ABSTRACT
FROM AUTHOR]
38. О двух дважды четных самодвойственных бинарных кодах длиной 160 и минимальным весом
24.
On Two Doubly Even Self-Dual Binary Codes of Length 160 and Minimum Weight 24.
By: van Dijk, Marten; Egner, Sebastian; Greferath, Marcus; Wassermann, Alfred. p408-411, 4p;
Ключевые слова: BINARY system (Mathematics), BINARY-coded decimal system, CIPHERS, CODING
theory, DECIMAL system, MATHEMATICS
Abstract: This correspondence revisits the idea of constructing a binary [m n, mk] code from an [n, k] code
over F_2^m by concatenating the code with a suitable basis representation of
F_2^m over F₂. We construct two nonequivalent examples of doubly even
self-dual binary codes of length 160 which turn out to be of minimum distance 24. This improves the lower
bound for this class of codes, whereas the upper bound Is given by 28. The construction at hand seems to be of
interest beyond this particular example. [ABSTRACT FROM AUTHOR]
39. Декодирование списков обобщённых кодов Рида-Соломона с использованием коммутативных
колец.
List Decoding of Generalized Reed -- Solomon Codes Over Commutative Rings.
By: Armand, Marc A.. p411-419, 9p;
Ключевые слова:*ALGORITHMS, BINARY system (Mathematics), BINARY-coded decimal system,
CIPHERS, CODING theory, MATHEMATICS
Abstract: We show that the list decoding procedure of Guruswami and Sudan may be used to decode
generalized Reed-Solomon (RS) codes defined over commutative rings with identity. An algorithm for
performing the first of the two phases of this decoding procedure is also given. In particular, we show that for
generalized RS codes over chain rings, the probability of picking an incorrect codeword from a given list can be
reduced by increasing the size of the code alphabet while keeping the length and minimum (Hamming) distance
of the code constant. [ABSTRACT FROM AUTHOR]
40. Элементарная конструкция кодов из групп единиц, принадлежащих к остаточным кольцам
полиномов.
An Elementary Construction of Codes From the Groups of Units of Residue Rings of Polynomials.
By: Reid, Les; Wickham, Cameron. p419-420, 2p;
24
Ключевые слова: ALGEBRA, BINARY system (Mathematics), BINARY-coded decimal system. CIPHERS,
CODING theory, MATHEMATICS
Abstract: In this note, we present an elementary verification of the minimum distance of some codes
constructed by Xing. We show that the codes obtained from this construction are subsets of cosets of linear
codes with a given parity-check matrix. [ABSTRACT FROM AUTHOR]
41.
Correction to "On the Asymptotic Performance of the Decorrelator" and "An Optimal Whitening Approach to
Linear Multiuser Detection". p421-421, 1p;
Ключевые слова: ALGEBRA, ERRATA
Abstract: Presents a correction to the articles "On the Asymptotic Performance of the Decorrelator" and "An
Optimal Whitening Approach to Linear Multiuser Detection."
42. Алгоритмы сжатия и кодирования.
Compression and Coding Algorithms.
By: Kieffer, John C.. p422-422, 1p;
Ключевые слова: ALGORITHMS, BOOKS -- Reviews, NONFICTION
Abstract: Reviews the book "Compression and Coding Algorithms," by Alistair Moffat and Andrew Turpin.
25