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DR. AVRAHAM KUDISH
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Monitoring Solar Radiation. A method for the characterization and comparison of
different sites with regard to their suitability for the utilization of solar energy was
developed on the basis of statistical analysis of the solar radiation intensities at those
sites. Each monthly data set of the daily global, horizontal beam, and diffuse radiation
intensities was analyzed for the following parameters: monthly average of daily
radiation intensity, coefficient of variation, skewness and kurtosis. The values of the
skewness and kurtosis were applied to describe the distribution curves for each set of
radiation intensity data.

Photoclimatherapy at the Dead Sea. The Dead Sea basin, the lowest terrestrial point
on earth, is recognized worldwide as a natural treatment center for patients with various
cutaneous and rheumatic diseases. The major skin disease treated at the Dead Sea is
psoriasis with more than 85% of patients showing excellent improvement to complete
disappearance of the symptoms after four weeks of treatment. These findings are
thought to be associated with the unique spectrum of ultraviolet radiation in the Dead
Sea area. To investigate this supposition, UV measurements were conducted
continuously at Neve Zohar, which is situated in the Dead Sea basin (-375 m), and, for
purposes of comparison, in Beer-Sheva (+315 m). The measurements were performed
with a Microtops II Ozone Monitor and Sunphotometer (Solar Light Co., Inc.) system,
which was originally designed to monitor the thickness of the ozone layer. It was found
that the ultraviolet radiation at the Dead Sea is attenuated relative to that in Beer-Sheva
due to the increased optical path length and the consequent enhanced scattering (i.e.,
natural attenuation). More importantly, at the Dead Sea, UVB radiation is attenuated to
a greater extent than UVA radiation, with the shorter erythema-causing UVB
wavelength (about 305.5 nm) being significantly decreased vis-a-vis the longer
therapeutic UVB wavelength (about 312 nm). It was also found that the relative
radiation intensities, i.e., erythema-to-therapeutic wavelength ranges within the UVB
spectrum are a function of the time of day, peaking at solar noon and decreasing
towards the early and late hours of the day. Diurnal measurements of the relative
radiation intensities can thus be used to design a photoclimatherapy protocol that
minimizes exposure to the erythema rays while optimizing the dose of beneficial
wavelengths.

Aerosol Composition and Particle Size Distribution of the Air at the Dead Sea. As
part of an ongoing study on the bioclimatological parameters in the Dead Sea Basin, the
aerosol composition and particle size distribution of the atmosphere in this region is
being determined. During the latter part of 2000, preliminary aerosol measurements
were initiated at the Dead Sea by means of a TE-6000 PM10 MFC high-volume air
sampler (Tisch Environmental, Inc.) for particulate matter 10 microns or less together
with Andersen Series 230 high-volume cascade (4) impactors.

Solar Desalination. A simulation model describing a solar collector containing a
selectively coated, polymeric, double-walled absorber plate with parallel fluid flow
channels was developed and validated utilizing experimental data from a solar collector
module. The simulation model contained a refined radiative energy balance, which took
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into consideration the fact that the glazing may not be totally opaque to long wavelength
radiation. The model was solved by applying numerical integration to the non-linear
differential equations describing the system. The validated simulation model was then
utilized to perform sensitivity studies on the design parameters of the system.
Relevant Publication
Kudish, AI, Evseev, EG, Walter, G and Leukefeld, T: A simulation study of a solar
collector with a selectively coated polymeric double-walled absorber plate. Energy
Conversion and Management (in press).
Ianetz, A, Lyubansky, V, Evseev, EG and Kudish, AI: Correlations for determining the
daily diffuse radiation as a function of daily beam radiation on a horizontal surface in
the semi-arid region of Israel. Theoretical and Applied Climatology (in press).
Kudish, AI and Evseev, EG: Statistical relationships between solar UVB and UVA
radiation and radiation measurements at two sites in Israel. Int. J. Climatology 20:759770; 2000.
Ianetz, A, Lyubansky, V, Setter, I, Evseev, E.G and Kudish, A.I: A method for
characterization and inter-comparison of sites with regard to solar energy utilization by
statistical analysis of their solar radiation data as performed for three sites in the Negev
region of Israel. Solar Energy 69:283-293; 2000.
Kudish, AI, Mink, G, Evseev, EG and Horváth, L: Technical and economic features of
advanced air-blown solar desalination systems. International Congress Energy and the
Environment 2000; 2000 Oct.; Opatija. (p. 89-97). (Proceedings, vol. I).
Ianetz, A, Lyubansky, V, Setter, I, Evseev, EG and Kudish, AI: An inter-comparison of
the radiation intensities measured at three sites in the southern region of Israel by
regression analysis. World Renewable Energy Congress-VI, Renewables: The Energy
for the 21st Century; 2000 July; Brighton. (p. 2477-2480). (Proceedings, vol. IV).
Mink, G, Horváth, L, Evseev, EG and Kudish, AI: Performance and analysis of a multipleeffect solar still utilizing an internal multi-tubular heat exchanger for thermal energy
recycle. International Solar Energy Society Conference, Solar World Congress; 1999
July; Jerusalem. (p. 226-235). (Proceedings, vol. III).
Kudish, AI, Evseev, EG, Horváth, L and Mink, G: Performance and analysis of a multipleeffect solar still utilizing solar and/or waste thermal energy. International Solar
Energy Society Conference, Solar World Congress; 1999 July; Jerusalem. (p. 216225). (Proceedings, vol. III).
Lyubansky, V, Ianetz, A, Seter, I, Kudish, AI and Evseev, EG: Characterization and intercomparison of the global and beam radiation measured at three sites in the southern
region of Israel by statistical analysis. International Solar Energy Society Conference,
Solar World Congress; 1999 July; Jerusalem. (p. 419-426). (Proceedings, vol. I).
Kudish, AI, Evseev, EG, Rommel, M, Köhl, M, Walter, G and Leukefeld, T: Research and
development of solar collectors fabricated from polymeric material. International Solar
Energy Society Conference, Solar World Congress; 1999 July; Jerusalem. (p. 40-49).
(Proceedings, vol. III).