Towards Adaptive Learning Systems Based on Fuzzy-Logic Soukaina Ennouamani(&) and Zouhir Mahani Ibn Zohr University, Agadir, Morocco soukaina.ennouamani@edu.uiz.ac.ma, z.mahani@uiz.ac.ma Abstract. E-learning systems have the ability to facilitate the interaction between learners and teachers without being limited by temporal and/or spatial constraints. However, the high number of students at universities, the huge number of available learning in the web, the differences between learners in term of characteristics and needs make the traditional e-learning systems more limited. For this purpose, adaptive learning has been recently explored in order to cope with these limitations and to meet the individual needs of learner. In this context, many artificial intelligence methods and approaches have been integrated in such computer-based systems in order to create effective learner models, structured domain models, adaptive learning paths, personalized learning format, etc. Such methods are highly recommended for designing adaptive e-learning and mlearning systems with good quality. In this paper, we focus only on one of these methods, called fuzzy logic, which is widely used in educational area. We present the integration of fuzzy logic as a valuable approach that has the ability to deal with the high level of uncertainties and imprecision related to learners’ characteristics and learning contexts. Keywords: E-learning Adaptive learning Personalized education Artificial intelligence Fuzzy logic Fuzzy inference systems 1 Introduction In recent years, computer-based learning is considered as one of the research areas that have attracted the attention of many researchers, and particularly e-learning that has had an impressive revolution in the field of smart learning. In this context and based on the use of Information and Communication Technologies (ICT), e-learning environments have the potential to be integrated in heterogeneous groups of learners in order to enhance their experiences and to provide them with a myriad of learning resources. In fact, smart learning platforms support the flexible teaching-learning process through mitigating temporal and spatial constraints [1]. In this context, teachers who used to know everything become teachers who must be continuously learning and reflective on their knowledge and skills [2]. It becomes more and more difficult to satisfy every learner’s needs, and to achieve the desired quality of teaching and learning which is continuously changing over time. This is because of instructors who can not adjust their teaching strategies for every single learner, especially at universities where the number of students is high. In addition to © Springer Nature Switzerland AG 2019 K. Arai et al. (Eds.): CompCom 2019, AISC 997, pp. 625–640, 2019. https://doi.org/10.1007/978-3-030-22871-2_42 626 S. Ennouamani and Z. Mahani this, the total number of remote learners makes the diagnosing of their interests and the determination of the best instructional actions, a difficult task for instructors [1]. In addition, e-learning is challenged by a considerable number of limitations related to the technical aspects, viz. crowded learning platforms, various user profiles, huge number of learning resources, etc. These limitations have encouraged researches in the field of smart learning to move forward to adaptive e-learning, which is an appropriate approach for heterogeneous learning groups [3]. Therefore, the integration of new methods and tools becomes an obligation in order to map with the new learning requirements. Artificial intelligence based methodologies are one of the considerable techniques that have been used to design intelligent educational systems [4]. Various artificial intelligence approaches (Bayesian Network, Machine Learning, Heuristic Methods, Ontology Construction, Fuzzy Logic) have been integrated to solve an important number of problems related to e-learning. Each solution has been designed regarding to the objective of each proposal, such as recommendation, content adaptation, format personalization, learning path generation, learning collaboration, etc. In this paper, we introduce the use of fuzzy logic in e-learning as a significant method to create practical learner models and/or to design learning device parameters in order to develop adaptive e-learning systems. In order to help researchers to understand the artificial-intelligence-based learning systems, this paper focuses only on fuzzy logic and describes its integration trends into some adaptive educational systems. Furthermore, we aim to analyze the importance of this integration to enhance the effectiveness of different adaptive e-learning solutions, and to review up to date application developments of these solutions. To achieve this objective, this paper is structured as follows: The second section draws on the concept and the definition of smart learning as well as the adaptation in learning systems. The third section presents the fuzzy logic by introducing Zadeh’s fuzzy theory, fuzzy IfThen rules as well as fuzzy inference systems. The next section discusses the fuzzybased adaptive learning systems by reviewing how the some previous related works have integrated this logic to design adaptive e-learning systems. After all, we conclude our paper and we present our future work and perspectives. 2 Adaptation in Smart Learning Environments 2.1 Smart Learning Authors in [5], claimed that “there is no clear and unified definition of smart learning so far”. However, and in spite of the difficulty of forming a definition of smart learning that has a high usage in our daily life, many researches attempt to define it. In [6], authors reported that smart learning environments not only employ digital technologies in supporting learning, education as well as training but also provide a significant design of the future learning environments. In fact, the word “smart” is now continuously used in the field of educational research in order to create new concepts, say, Smart Education, Smart University, Smart Learning, Smart Classroom, and Smart Learning Environment [7]. This drives us to mention the meaningful definition suggested by [8] who stated that: “the essence of smarter education is to create intelligent environments by using Towards Adaptive Learning Systems Based on Fuzzy-Logic 627 smart technologies, so that smart pedagogies can be facilitated to provide personalized learning services and enable learners to develop talents of wisdom that have better value orientation, higher thinking quality, and stronger conduct ability.” One of the important instances of smart learning is e-learning that utilizes computer, internet and network technologies as an integral part to facilitate learning anytime and anywhere. In this perspective, authors in [9] indicated that internet has become a central core of the educative environment experienced by learners, and that explains the quick adoption of e-learning all over the world. Furthermore, e-learning becomes a prominent alternative to traditional learning paradigms and the predominant method of delivering teaching materials to a learner supported by an instructor with the aim of being evaluated [6, 10]. “E-Learning is an umbrella term that describes learning done at a computer, usually connected to a network, giving us the opportunity to learn almost anytime and anywhere” [11]. It is known that e-learning takes the advantages of computer networks to provide leaning resources at/outside classrooms. It also operates internet technologies to insure the storage as well as the information sharing. Therefore, e-learning can be considered as a rich experience that generates new skills, understanding and knowledge for any teacher, instructor, trainer, or manager hoping to offer a suitable learning for their learners. On the other hand, and to be accurate, we have observed a fast transition in learning methodologies. It has been started with d-learning (distanced learning), then the progress of Information and Communication Technologies has led to e-learning (electronic learning) and recently, m-learning (mobile learning) has become the latest progress in this area. M-learning is usually associated to the use of handheld devices, namely, mobile phones, game consoles, laptops, and tablet computers in order to perform training and teaching activities in a dynamic learning environment [12]. Mobile technologies are becoming more ubiquitous, pervasive and networked, with important capabilities for context awareness and internet connectivity [13]. As a result, learning has jumped from classrooms environment to real and virtual learning environments, and has become more personal, adapted and collaborative. Thus, the integration of mobile learning is seen, by the majority of researches, as an important alternative to enhance learner’s interest and motivation [14]. Authors in [15] and [16] indicated that m-learning cross multiple contexts including space and time borders, and involve social and effective interactions through using personal electronic devices. These devices enable the mobile users to take the advantage of virtual learning activities in order to improve their learning abilities without being tethered to a specific location, say, university environment [17]. Other researchers [18, 19] pointed out that m-learning has the strength of ubiquity, availability as well as technical functions such as geospatial technologies, social networking, sensors detection, multimedia tools, visual identification and audio recorder. These features have promoted e-learning to m-learning as a wireless learning that combines learning resources from the current real environment with the numerical one. The above definitions of e-learning and m-learning have been frequently cited by the majority of academic researches. This allow us to describe how ICT can change the traditional paradigms of teaching and learning, and consequently to discover how to use these technologies to transform learning from a limited academic activity into a flexible and enjoyable daily experience. 628 2.2 S. Ennouamani and Z. Mahani Adaptation in Learning Systems At the turn of the century, the considerable growth in the field of computer-based learning including e-learning and m-learning have performed further concepts, viz. adaptive/personalized learning systems, recommendation in learning systems, collaborative learning systems and so on. The main core of this progress is the integration of artificial intelligence techniques to obtain the desirable solution regarding the users’ needs, objectives and motivations. In this paper, we pay a considerable attention to adaptive and personalized learning systems only. Researches in adaptive systems can be traced back to the early 1990s. At that period of time, teachers started to make considerable efforts to evaluate the ability of their students, including their knowledge level, skills, background, learning styles, interests, etc. The principal objective was to take these characteristics into consideration in order to provide courses in a way that fits every student’s needs. This adjustment can be done inside classrooms with smaller number of participants [20] or for one-to-one teaching [21]. However, and since the majority of traditional classrooms consist of a huge number of students, teachers definitely can not consider each learner’s needs to afford the tailored learning. In order to solve the above problems, and since the ultimate goal of any smart learning system is to maximize the student’s quality of learning, several researchers have begun to study the different possibilities to adapt the educational systems and to facilitate the learning process in an individual way. In this context, learner modeling techniques that have been introduced in Intelligent Tutoring Systems (ITS) are also integrated into the learning applications aiming to be adaptive and personalized [22]. As indicated in [23], adaptive e-learning systems have the power to provide students with personalized online learning materials and services. Adaptive educational systems attempt to enhance student learning experiences by modeling the ideal learning environment based on their specific needs [24]. Therefore, this kind of systems are getting more attention due to their potential of making learning available, more flexible and in a dynamic design. Generally, the target of any adaptive learning system is to personalize the different learning approaches in order to achieve the students’ satisfaction, and to facilitate the learning process [25]. In other words, learners must be modelled in a way to assimilate not only their needs but also their individual characteristics that can be classified in different categories. Thus, and through this kind of software, many connections and links are created between learner characteristics and available learning resources. As mentioned in [10], the development of any adaptive learning system involves three components that dynamically interact with each other, namely, learner model, domain model and adaptation model (Fig. 1). The learner model is the core of these systems that provides a structured presentation of the learner characteristics [26]. The domain model is a structured design of the existing knowledge based on an abstract representation [27]. Finally, the adaptation model is the bridge between the learner and domain models by combining the learners’ needs and characteristics with the relevant learning materials [28]. Towards Adaptive Learning Systems Based on Fuzzy-Logic 629 Fig. 1. Adaptive e-learning system components [10] According to [22] and [29], an adaptive system must be able to manage a structured learning navigation in order to generate suitable learning resources, to control each learner activity, to estimate learner’s behavior and interactions, to deduce user’s needs and preferences and to create better links between learner model and domain model. In fact, every adaptive e-learning or m-learning system has a specific target, namely, adapting learning path, contents, support/instruction, and presentation. The target can not be reached without having a basic source of adaptation that can be classified as learner characteristics and learner interactions. A predetermined pathway that can be followed to achieve that target is also required in such educational systems (Fig. 2). These three elements are considered to determine what information about the learner should be collected, and how it will be used in order to provide the desired adaptation [30, 31]. In addition, m-learning systems can be considered more adaptive than e-learning systems. This is due to the available sensor detectors in mobile devices that allow to provide more information about the learner’s context. In other words, mobile sensors can determine the learner’s motions via the accelerometer, the distance between the learner and the handled device using the proximity sensor, the environmental noise through the microphone, etc. Consequently, the user’s context can be predicted with more accuracy allowing the system to build a conception about the appropriate presentation of the learning content. 630 S. Ennouamani and Z. Mahani Fig. 2. The tripartite structure of adaptive learning systems [38] 3 Fuzzy Logic Theory and Fuzzy Inference Systems (FIS) 3.1 Fuzzy Logic Theory Obviously, our brains have the capacity to deal with the facts which have a lack of exactness. Thus, we can answer a question about how much a car is near to another, using the expressions which are open to more than one interpretation, for example, very near, not very near, far away, quite away, etc. In contrast, machines in general and computers in particular can not give such precision, because it is based on binary set (0,1) membership. Therefore, and based on this issue, fuzzy logic was introduced by Zadeh [32] as a further theory to the classical set theory. The fuzzy set theory was developed to generalize the classical crisp sets, and to answer such uncertain questions using the concept of partial membership. In literature, it has been proved that the fuzzy set theory offers a considerable rang of methods to clarify the ambiguous and uncertain situations. It is a convenient solution to manage the precision of information as well as the fuzziness of different states [33]. Fuzzy sets deal with vague terminologies, viz. young, rich, tall, and others. It represents a transition from the rigid membership of a class of objects inside the crisp set (1 if it belongs to the set, and 0 otherwise), to the fuzzy set that gives the opportunity to have a normalized partial grade of membership (a value between 0 and 1) [34]. Figure 3 represents an example of the degree of membership of three fuzzy sets related to the determination of the age. Towards Adaptive Learning Systems Based on Fuzzy-Logic 631 Fig. 3. Hierarchical structure of a linguistic variable [39] Zadeh introduced fuzzy set theory to solve our daily problems of uncertainty caused by incomplete data as well as human subjectivity [35]. It can be considered as the most compatible method with the human-being decision-making process [36], using linguistic variables as well as the degrees of membership which symbolize the grade of stability of an item inside a fuzzy set [37]. A fuzzy set is defined as an ordered set (x, lA(x)), where x belongs to X and lA ðxÞ belongs to [0, 1], equipped with a membership function lA ðxÞ : X ! [0, 1], where: lA ðxÞ ¼ 3.2 8 > < > : 1 ½0; 1 0 ; x belongs to A ; x is partially in A ð1Þ ; x does not belongs to A Fuzzy If-Then Rules and Fuzzy Inference Systems (FIS) – Fuzzy If-Then rules: Zadeh’s theorem has become more useful when Mamdani [40] employed it in a practical application to control an automatic steam engine. Mamdani’s method is a relational model known as a linguistic method because the premise and the outcome are computed with words. It is a manually developed method that uses defined rules in order to generate the adequate results via a fuzzy membership function [41]. Mamdani’s fuzzy If-Then rules are the expressions of the form “IF A THEN B”, where A and B are labels of fuzzy sets [32] associated with convenient membership functions. Considering the flowing example: If the speed is high; then apply the brake a little 632 S. Ennouamani and Z. Mahani In this example, “speed” is a linguistic variable, and “brake” is also a linguistic term characterized by a membership function. This example represents a reasoning situation in an environment of imprecision guided by the human ability of making decisions. On the other hand, Takagi and Sugeno [42] introduced another form of if-then rules that follow a data driven model. In contrast to Mamdani’s rules, this method is based on historical data computed with weighted average [41]. Another example suggested by [43] describes the resistant force on a moving object: If velocity is high; then force ¼ k ðvelocityÞ2 Where, “high” is a linguistic proposition described by a membership function. After then, the inferred conclusion is described by a non-fuzzy equation of the input (velocity). The above types of fuzzy if-then rules have been employed in a myriad number of application domains. They represent an essential block in the Fuzzy Inference Systems (FISs) that provides a description of the system’s workflow. FIS are explained in the following paragraphs. There are many application domains of fuzzy logic and fuzzy sets, namely, Fuzzy Inference Systems(FIS), Fuzzy Decision Trees (FDT) and so on. In this paper, we focus on FIS because it has been integrated in the majority of adaptive computer-based educational systems that we reviewed in this paper (Sect. 4). – Fuzzy Inference Systems (FIS): FIS or fuzzy-rule-based systems introduced by Mamdani consist of four blocks, namely, Fuzzifier, Fuzzy Rule Base, Inference Engine, and Defuzzifier (Fig. 4). These blocks are also known as the basic stages of any FIS, described as follows: Fig. 4. The Mamdani’s fuzzy inference system • Fuzzifier: Based on the crisp sets of input data, the Fuzzifier converts this input to fuzzy sets using membership functions as well as fuzzy linguistic variables. In this Towards Adaptive Learning Systems Based on Fuzzy-Logic 633 block, the performed process is known as Fuzzification (crisp to fuzzy) [41]. Linear triangular and linear trapezoid membership functions are frequently used in FIS [44]. • Fuzzy Rule Base: It represents the key block in any FIS by containing a number of fuzzy if-then rules (Mamdani and/or Sugeno types). As claimed by [37] and [41], these rules are determined through training and/or historical data, or defined by experts. Each fuzzy if-then rule can be considered as a native description of the scheduled system that applies the membership values for prospective inferences. • Inference Engine: It applies the fuzzy rules on the fuzzy input generated by the Fuzzifier in order to establish the desired results. This engine represents the kernel of decision making process [45] which is designed to dynamically integrate the different system resources in a way to run a series of fuzzy-based outputs. • Defuzzifier: This block is responsible of transforming the fuzzy output generated by the inference engine into a crisp output. It allows to map each fuzzy set with one crisp set in order to create a transition from linguistic values to numerical values using, again, the membership functions. This process is called Defuzzification, it consists of performing the inverse transformation (fuzzy to crisp) and it has the most computational complexity [37]. Different Defuzzification methods and approaches have been introduced in the literature, namely, the center of area method, bisector of area method, mean of maximum method, smallest of maximum method, and the largest of maximum method [46]. As concluded by [43], a fuzzy inference system that involves fuzzy if-then rules can model the qualitative human knowledge aspects and reasoning processes, without using accurate quantitative values as well as numerical sources and analyses. 4 Fuzzy-Based Adaptive Learning Systems: Related Works Due to its popularity, fuzzy logic has become successfully applied in a variety of complicated systems and applications that are involving a lack of exactness [47, 48]. In recent years, fuzzy logic has been highly employed in computer-based learning in order to cope with imprecision as well as the variation of the users’ characteristics, device features, and domain knowledge structure. Fuzzy logic does not need a lot of data to be executed, it has predictable processes [49], and these are the main reasons why it has been and still used for developing e-learning systems. Fuzzy logic has been used for achieving various goals in computer-based educational systems, namely, for creating suitable assessment tests [50], predicting the learning styles in web environments [51], evaluating a web based LMS [52], diagnosing students’ cognitive profiles and comprehension [53], creating a system that delivers personalized tips to students [54], and so on. In this paper, we focus only on the use of fuzzy logic in adaptive learning systems through presenting and studying a list of related works. Moreover, we present the different techniques used in this area as well as how FIS is employed to create such kind of learning systems. In [45], the authors introduced and designed an online educational module based on fuzzy set theory. They aim, through this proposal, to generate adaptive learning 634 S. Ennouamani and Z. Mahani activities in a virtual environment. The basic motivation of this solution is that a learner model is known by the uncertainty of knowledge acquisitions as well as decision making process. Thus, fuzzy logic has been used to model learner profiles in order to present the suitable learning activity in an individual way. This system starts with a collection of all data that establish a learner profile as a crisp input for the FIS. After that, the fuzzification step transforms the crisp input to a fuzzy input using the membership functions. Half trapezoidal, two triangular and half right trapezoidal functions are used in this model. Always regarding the FIS stages, the inference engine starts working in the third stage by the use of rules base related to the learner’s age, gender, level of knowledge, level of difficulty of the learning activity as well as the learning session duration. The inference engine uses if-then rules that allow to deduce the appropriate learning activity. At the end, the defuzzification is performed via the extraction of the suitable learning activity from the related data base, based on the value given by the inference engine. A personalized system for learning English proposed by [55] is based on learner profiles and aims to help students improve their English language competency through an extensive reading environment. The proposal uses learner preferences, fuzzy inference process, memory cycle updates, and analytic hierarchy process in order to provide learners with the most suitable English articles. The techniques of fuzzy inferences and personal memory cycle updates allow the system under consideration to extract the appropriate articles for the targeted learner’s ability as well as the desired vocabulary. The authors employed fuzzy inference mechanism respecting the four blocks described in the previous section, including the Input, the Fuzzifier, the Inference Engine and the Defuzzifier in order to determine the suitable articles from the available database for every single learner. In accordance with this objective, the considerable characteristics in this proposal are related to the article’s content and the learner’s language ability, namely, the Average Difficulty of Vocabulary (ADV), the Average Length of Sentence (ALS), the Total Length of Article (TLA), the Average Ability of Vocabulary of the learner (AAV), and the Article Correlation (AC). These characteristics represent the input of the FIS that are used in the following stage of Fuzzification in order to calculate the degree of membership using a trapezoidal type for each linguistic variable (low, medium, high). The inference step in this algorithm is fulfilled via 243 rules based on combining three linguistic terms and five fuzzy input items. In the final step, the Defuzzification involves the discrete center of area method in order to generate an output that represents how appropriate an article is for a determined learner based on a value between 0 and 1. The final decision is taken based on the maximum value that describes the most convenient article for a learner. This proposal represents a significant illustration of the integration of fuzzy logic in an adaptive e-learning system. Another work was suggested by [56] aims to use fuzzy sets to represent the learner’s knowledge level as a subset of the domain knowledge. The proposed approach is implemented and evaluated in a Mental Architecture Digitized model which is based on Fuzzy Cognitive Maps (FCM) in order to represent the dependence among the domain concepts. The use of fuzzy logic in this proposal performs the user modeling through the identification and the update of each learner’s knowledge level related to the concepts of the domain knowledge under consideration. Consequently, the system Towards Adaptive Learning Systems Based on Fuzzy-Logic 635 provides users with the significant adaptive tips through an automatic modeling of the learning or forgetting process of each learner regarding the FCMs. Fuzzy logic was also used to model the student profile presented in [57] for personalizing online educational systems. In order to meet with this objective, the authors have developed a fuzzy epistemic logic to present the learner’s knowledge state through a multi-agent based student profiling system. This system stores the learning activities and interaction history of each learner into the student profile database, and then the profiling data is abstracted into a learner model. Afterward, dynamic learning plans for each learner are established based on the student model and content model. Therefore, every single learner gets personalized learning materials, personalized quiz, and personalized advice. This fuzzy-based educational system have proven that the personalization has the strength of increasing learning motivation, and consequently enhancing learning effectiveness. In [58], a personalized competence-based instructional system called “InterMediActor” has been introduced. The system tends to generate an individualized navigation path for each learner based on the graph of dependencies between competences and student model. This proposal adopts fuzzy logic to deal with uncertainty of the student’s assessment, including marks as well as prerequisite knowledge. Like all fuzzy-logic-based systems, the first step of FIS is the Fuzzification where the system transforms the student’s mark value (crisp value between 0 and 1) into a linguistic value (negative, positive, or no mark) using the membership functions. Concerning prerequisite knowledge level, it has five linguistic terms: not, little, enough, well, and very well. The estimation of this characteristic is based on the marks obtained during the final-assessment tests. The Fuzzification of the level of difficulty is calculated for each competence of the course, and it is unchangeable during the session. Three membership functions are used to describe the level of difficulty, namely, easy, normal, and difficult. After Fuzzification, fuzzy if-then rules of the Inference Engine are applied for describing relations between the level of difficulty of the competence, the marks obtained in the final-assessment test for the competence, and the estimated prerequisites of this competence. At the end and regarding FIS stages, the linguistic values of the level of recommendation are defuzzified in order to be transformed into crisp values (step 4). To be accurate, more recommended, recommended, less recommended, and forbidden become 4, 3, 2, 1, and 0, respectively. A fuzzy-based framework for learning path personalization was suggested by [59]. It takes into consideration the most preferred learning material and the least preferred learning material. This by using the learning characteristics and pedagogical models that are based on the learner personality factors determined through Myers-Briggs Type Indicator (MBTI). Since Fuzzy logic is most suitable for working on imprecise input data and for supporting natural description of knowledge, fuzzy logic techniques are used in this proposal for enabling the system to classify learning material structure, and then to adapt the selection of possible learning which are suitable for the student’s fuzzy learning styles membership. For this purpose, the algorithm under consideration runs in a way to combine and mix two approaches, namely, learning style approach and fuzzy logic theory. It consists of three divisions; learning style (MBTI) approach, fuzzy logic approach and dynamic course adaptation. The four stages of FIS are respected, starting by Fuzzification stage that transforms the crisp learner’s personality 636 S. Ennouamani and Z. Mahani characteristics into the appropriate linguistic values. On the one hand, the input linguistic variables are the learner’s personality scores: extrovert, introvert, sensing and intuitive. On the other hand, the fuzzy outputs illustrate the learner’s acceptance level of the learning material: theory, example, exercise and activities. Afterward, the inference system based on 76 rules (if-then statements) and various inputs combined with AND operator, generate multiple consequents. At the end, every student receives the appropriate structure of learning materials which match his/her learning style and personality. The authors in [60] present the design and implementation of a fuzzy-logic expert system for adaptation in e-learning. This model aims to introduce an adaptive system for learning English as a second language, based on the student’s knowledge and characteristics. The proposed approach follows the process of detecting the learner’s sensory preferences in order to decide the appropriate learning content form. This is by the use of an expert system which detects the learner’s knowledge level, helps to decide the needed part of courses, adapts and presents the tailored learning materials based on the previous characteristics. Regarding FIS, the Fuzzification of the student’s knowledge, assessment tests as well as his/her preferences is always followed by the performance of the Inference Engine. At this level, if-then rules determined by a language education expert are employed to deal with the input related to the number of correct answers within the category (V1), weight of correct answers within the category (V2), importance of the category for further studies (V3), and time spent over answers of the category (V4). The output linguistic variable from the fuzzy expert system represents the need of further studies of the given category (V5). At the end, appropriate learning materials are selected for each category through an algorithm that calculates its importance (ISM). As a result, based on the length of the study time, the study variant is adapted and a reduced one is generated when the study time is less. It includes only the necessary learning materials. In this section, we presented how fuzzy-logic can be integrated and involved in adaptive learning systems. The related works described above follow the steps of creating a Fuzzy Inference System in order to generate adaptive and personalized elearning platforms. This is by operating Fuzzification, Inference Engine based on rule base, and Defuzzification. These stages are the core of the adaptation process in any fuzzy-based adaptive learning system. 5 Conclusion and Future Work The adaptation of learning has a positive effect on the learning process, leading to an increased efficiency, effectiveness as well as learner satisfaction [61]. In this context, the integration of pedagogical approaches as well as artificial intelligence methodologies becomes necessary to meet with the learner’s need and to deliver a more interactive learning environment. For this purposes, we presented in this paper one of the artificial intelligence methods called fuzzy logic. As claimed Mamdani, fuzzy logic allows to “compute with words” which cannot be accomplished using other methods, and it has the ability to represent human conceptualizations in a realistic way. Towards Adaptive Learning Systems Based on Fuzzy-Logic 637 Therefore, fuzzy logic can contribute to create an big number of useful solutions in the modelling of intelligent systems [57] including computer-based educational systems. In this perspective, we studied the integration of fuzzy logic in adaptive learning systems by reviewing some previous research in this field. We can deduce that fuzzy logic is one of the significant ways to improve the system performance and to make it able to generate serious decisions about the adaptation of learning materials that must be delivered. This is because of the learner characteristics’ fuzziness that can be handled with such method of resolving uncertainty problems. Consequently, this integration increases the learner’s performance, comprehension, skills as well as his/her satisfaction. In addition to this, authors in [62] share the same opinion by indicating that an algorithm based on fuzzy logic helps to select the ideal model based on a set of inputs and model specifications. The main motivation of our next research is to develop a new fuzzy-based adaptive learning system for higher education. We aim to incorporate the fuzzy logic in our previous model of m-learning systems [29] in order to deal with the uncertainty of the learner characteristics as well as context parameters. 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