Sylvia Encheva - Academia.edu (original) (raw)
Papers by Sylvia Encheva
Advances in Intelligent Systems and Computing, 2017
Vague Functional Dependencies are often employed while searching for new attribute dependencies. ... more Vague Functional Dependencies are often employed while searching for new attribute dependencies. When it is established that one set of attributes implies another set of attributes it can occur that it is easier or faster to obtain values for the first set rather than for the second. This can be very useful in case the attributes in the second set are the ones providing data for reasonable conclusions and predictions.
Over the last few years mergers in higher education are taking place all over the world. A number... more Over the last few years mergers in higher education are taking place all over the world. A number of institutions, that are currently negotiating or have already completed a merger, report about certain difficulties they have experienced. Different cultures, geographical distances, and uncertainty about future developments are just a few examples of problems discussed by the research community. In addition comes the issue of optimizing processes concerning placing faculty members in new units. Before a merger takes place academic staffs are usually placed in small groups. In this work we propose an approach for systematic assignment of academic staffs to larger departments in a new organization.
Intelligent Computing and Communication, 2020
Reduction of both CO2 emissions and energy consumption is of high importance in Norway. One of th... more Reduction of both CO2 emissions and energy consumption is of high importance in Norway. One of the numerous areas where this can be achieved is maritime transport in general and ferry transport in particular. In this work, we present an approach for finding which of the existing solutions is closest to the one a new county would like to implement. Such a choice is effected by a number of factors among which are political, economic, social, to name a few. While some of them are nearly impossible to quantify, the effect of others is not known due to some confidentiality issues. In order to avoid the effect of bias assumptions and subjective guesses we base our work on publicly available data.
While most well established universities have developed their research structures based on decade... more While most well established universities have developed their research structures based on decades of experience and adjustments, others focus on creating research clusters. Both ways however require considerable amount of time and resources. Merging educational organizations are often in need to build their research structures at faculty level without using extra time and resources. This work presents an approach facilitating development of a research structure in educational organizations.
A solution to care services crisis by using current technology in which an incentive-based system... more A solution to care services crisis by using current technology in which an incentive-based system is proposed. A method for trading care services using cryptocredit is suggested to facilitate a citizen to citizen collaboration. Based on blockchain technology, citizens can trade care services among each other.
This work aims at facilitating processes of cooperative decision making related to resource alloc... more This work aims at facilitating processes of cooperative decision making related to resource allocation in educational organisations. Different institutional units usually have a variety of ways to work, present earlier results, and evaluate what is important for the future. Thus even the involved parties generally agree on the main criteria governing their decisions, they still have to find a way to compare available data and to see to which degree any of the submitted proposals is going to contribute to realizing institutional goals. Employing a decision support system will decrease the amount of manual labor and probability for human error.
Delivering of automated personalized assistance to students is becoming an integral part of nearl... more Delivering of automated personalized assistance to students is becoming an integral part of nearly all recently developed learning systems. While the goal is the same most of the time, i.e. facilitating the cognitive process of acquiring skill and knowledge, the reasoning methods supporting choices of appropriate study materials vary considerably. Quite often gathering personal data is a prerequisite for providing tailored assistance. Security concerned users however are unwilling to submit personal data via unknown channels and therefore cannot have the benefits of such aids in teaching. An approach based on students perceptions but not requiring personal data is in the center of this work. Ordered sets and concept lattices are used for ranking and visualizing of acquired results.
Lecture Notes in Computer Science, 2021
Advances in Intelligent Systems and Computing, 2017
Students enrolled in higher education usually possess a wide range of skills developed through th... more Students enrolled in higher education usually possess a wide range of skills developed through their studies. More often than not they experience skills assessment conducted by focusing only on a single skill at a time. What seems to receive less attention in such assessments is related to finding a systematic way of detecting and consecutively overcoming difficulties caused by a need to apply multiple skills for solving join problems. Our suggestion to handle such troublesome cases is based on the binomial theorem and category scores.
Lecture Notes in Computer Science, 2016
Suppliers’ selection is important for any enterprise. Most available approaches for facilitating ... more Suppliers’ selection is important for any enterprise. Most available approaches for facilitating processes of choosing suppliers from a number of alternatives focus on which criteria are to be used according to a particular business. This implies that the role of a decision maker is to confirm or modify the outcome of an already chosen method. In this work we present a way of incorporate decision maker’s opinion along with previous customers experience in the process of suppliers selection.
Lecture Notes in Computer Science, 2016
Merging organizations face a number of challenges related to creation of a new establishment. Sho... more Merging organizations face a number of challenges related to creation of a new establishment. Short deadlines put serious pressure on those, responsible for planning and implementing all possible types of changes. The main issue we direct attention on in this work is concerned with placing employees in new units according to their competencies in a well-organized and controlled way. Isotone Galois connections are used to secure a systematic approach for establishing a correspondence between employees’ competencies and units’ contents.
Proceedings of the 2016 International Conference on Artificial Intelligence: Technologies and Applications, 2016
Knowledge and skills students gather for a period of time is difficult to estimate. Learning is e... more Knowledge and skills students gather for a period of time is difficult to estimate. Learning is effected by a number of factors and prior knowledge is among the very important ones. Despite existence of a substantial amount of tests for assessing newly obtained knowledge and skills, there is still a need to provide tailored responses to answers students submit by connecting those answers to their prior knowledge. Lattice structures prove themselves to be especially useful for unveiling dependences among various factors.
Proceedings of the 2016 International Conference on Artificial Intelligence: Technologies and Applications, 2016
Students' knowledge assessment has occupied the attention of many researches pertaining to differ... more Students' knowledge assessment has occupied the attention of many researches pertaining to different disciplines. Recent areas of interest in this regard include availability of preliminary skills and status of latest obtained knowledge, selfassessment, grading methods, tests, hints, help functions, etc. Involvement of smart technology in assessment processes is another important issue which rapidly gains popularity among students and lecturers. What seems to have received less attention in earlier studies is a way to establish whether apparent lack of knowledge is related to intrinsic or explicit terms and concepts. Application of selected graphs is put forward in this work in an attempt to increase the likelihood of an improved knowledge assessment.
Proceedings of the 5th Wseas Congress on Applied Computing Conference and Proceedings of the 1st International Conference on Biologically Inspired Computation, 2012
In this paper we illustrate application of many valued context in the area of knowledge evaluatio... more In this paper we illustrate application of many valued context in the area of knowledge evaluation. While the classical binary approach clearly indicates relationships among objects and attributes it still does not provide any information on the degrees to which an object possesses an attribute. Many valued contexts allow inclusion of more detailed description on such dependences.
Proceedings of the 11th Wseas International Conference on Applied Computer and Applied Computational Science, Apr 18, 2012
Many educational institutions collaborate for developing joint bachelor, master and PhD programs.... more Many educational institutions collaborate for developing joint bachelor, master and PhD programs. Quite often in the process of completing learning materials, included in an intelligent tutoring system f. ex. they have to choose among different learning objects developed by different teams and originally intended to be presented to different type of students. In order to be effective this process should involve both content providers and IT experts. The objective of this paper is to show how a rough set theory based approach can facilitate the process of ranking available learning objects.
Ordering of humans preferences is a complicated process. In this paper we are exploring the prope... more Ordering of humans preferences is a complicated process. In this paper we are exploring the properties of symmetry groups for simplifying a readable graphical representation of orderings of preferences in a graph structure.
The authors of this paper have investigated t-error-correcting BCH codes over Z4. Such codes with... more The authors of this paper have investigated t-error-correcting BCH codes over Z4. Such codes with length ≤ 105 and dimension ≤ 13 have been constructed. They are described with their parameters and when Hamming weight and Lee weight are different corresponding generator polynomials are given. The generator polynomials are result of multiplication of primitive basic irreducible polynomials over Z4. Graeffe's method has been used for finding a polynomial whose roots are the squares of the roots of p(x) where p(x) E Z22[x] is a primitive basic irreducible polynomial.
The concept of Z4 - linear codes has proved to be successful to describe certain well known non-l... more The concept of Z4 - linear codes has proved to be successful to describe certain well known non-linear binary codes, for which the parameters are extraordinary good. In this paper we start an investigation of linear, binary codes, which are Z4, - linear, and the purpose is to find out to what extend the concept of Z4, - linearity is also relevant to describe linear, binary codes, which has optimal parameters. A number of examples are given and two basic structure theorems for the codes in question are formulated.
Proceedings of the 2015 International Conference on Modeling, Simulation and Applied Mathematics, 2015
Selection of an optimal knowledge assessment method appears to be a multiple criteria decision ma... more Selection of an optimal knowledge assessment method appears to be a multiple criteria decision making problem among many other things. There is hardly any doubt that working with humans knowledge is always done in the presence of uncertainties. It is also not a secret that a large number of experts in the field of knowledge assessment feel much more comfortable expressing their opinions and statements in linguistic terms and number intervals rather than with crisp values. In this work we address the problem of ranking alternatives for students' knowledge assessment. Interval number theory seems to be an appropriate approach to begin with, when considering the nature of such investigations. While the method is definitely useful for handling interval data it certainly does not indicate what two or more alternatives have in common. This type of information is often required when in real life situations the best theoretically proven alternative cannot be taken. Therefore we propose application of formal concept analyses on the same data in addition to the work performed with interval number theory. Combining these two methods can facilitate multiple attribute decision making processes where for some reasons outcomes of alternatives' rankings with interval numbers have to be reconsidered.
Advances in Intelligent Systems and Computing, 2017
Vague Functional Dependencies are often employed while searching for new attribute dependencies. ... more Vague Functional Dependencies are often employed while searching for new attribute dependencies. When it is established that one set of attributes implies another set of attributes it can occur that it is easier or faster to obtain values for the first set rather than for the second. This can be very useful in case the attributes in the second set are the ones providing data for reasonable conclusions and predictions.
Over the last few years mergers in higher education are taking place all over the world. A number... more Over the last few years mergers in higher education are taking place all over the world. A number of institutions, that are currently negotiating or have already completed a merger, report about certain difficulties they have experienced. Different cultures, geographical distances, and uncertainty about future developments are just a few examples of problems discussed by the research community. In addition comes the issue of optimizing processes concerning placing faculty members in new units. Before a merger takes place academic staffs are usually placed in small groups. In this work we propose an approach for systematic assignment of academic staffs to larger departments in a new organization.
Intelligent Computing and Communication, 2020
Reduction of both CO2 emissions and energy consumption is of high importance in Norway. One of th... more Reduction of both CO2 emissions and energy consumption is of high importance in Norway. One of the numerous areas where this can be achieved is maritime transport in general and ferry transport in particular. In this work, we present an approach for finding which of the existing solutions is closest to the one a new county would like to implement. Such a choice is effected by a number of factors among which are political, economic, social, to name a few. While some of them are nearly impossible to quantify, the effect of others is not known due to some confidentiality issues. In order to avoid the effect of bias assumptions and subjective guesses we base our work on publicly available data.
While most well established universities have developed their research structures based on decade... more While most well established universities have developed their research structures based on decades of experience and adjustments, others focus on creating research clusters. Both ways however require considerable amount of time and resources. Merging educational organizations are often in need to build their research structures at faculty level without using extra time and resources. This work presents an approach facilitating development of a research structure in educational organizations.
A solution to care services crisis by using current technology in which an incentive-based system... more A solution to care services crisis by using current technology in which an incentive-based system is proposed. A method for trading care services using cryptocredit is suggested to facilitate a citizen to citizen collaboration. Based on blockchain technology, citizens can trade care services among each other.
This work aims at facilitating processes of cooperative decision making related to resource alloc... more This work aims at facilitating processes of cooperative decision making related to resource allocation in educational organisations. Different institutional units usually have a variety of ways to work, present earlier results, and evaluate what is important for the future. Thus even the involved parties generally agree on the main criteria governing their decisions, they still have to find a way to compare available data and to see to which degree any of the submitted proposals is going to contribute to realizing institutional goals. Employing a decision support system will decrease the amount of manual labor and probability for human error.
Delivering of automated personalized assistance to students is becoming an integral part of nearl... more Delivering of automated personalized assistance to students is becoming an integral part of nearly all recently developed learning systems. While the goal is the same most of the time, i.e. facilitating the cognitive process of acquiring skill and knowledge, the reasoning methods supporting choices of appropriate study materials vary considerably. Quite often gathering personal data is a prerequisite for providing tailored assistance. Security concerned users however are unwilling to submit personal data via unknown channels and therefore cannot have the benefits of such aids in teaching. An approach based on students perceptions but not requiring personal data is in the center of this work. Ordered sets and concept lattices are used for ranking and visualizing of acquired results.
Lecture Notes in Computer Science, 2021
Advances in Intelligent Systems and Computing, 2017
Students enrolled in higher education usually possess a wide range of skills developed through th... more Students enrolled in higher education usually possess a wide range of skills developed through their studies. More often than not they experience skills assessment conducted by focusing only on a single skill at a time. What seems to receive less attention in such assessments is related to finding a systematic way of detecting and consecutively overcoming difficulties caused by a need to apply multiple skills for solving join problems. Our suggestion to handle such troublesome cases is based on the binomial theorem and category scores.
Lecture Notes in Computer Science, 2016
Suppliers’ selection is important for any enterprise. Most available approaches for facilitating ... more Suppliers’ selection is important for any enterprise. Most available approaches for facilitating processes of choosing suppliers from a number of alternatives focus on which criteria are to be used according to a particular business. This implies that the role of a decision maker is to confirm or modify the outcome of an already chosen method. In this work we present a way of incorporate decision maker’s opinion along with previous customers experience in the process of suppliers selection.
Lecture Notes in Computer Science, 2016
Merging organizations face a number of challenges related to creation of a new establishment. Sho... more Merging organizations face a number of challenges related to creation of a new establishment. Short deadlines put serious pressure on those, responsible for planning and implementing all possible types of changes. The main issue we direct attention on in this work is concerned with placing employees in new units according to their competencies in a well-organized and controlled way. Isotone Galois connections are used to secure a systematic approach for establishing a correspondence between employees’ competencies and units’ contents.
Proceedings of the 2016 International Conference on Artificial Intelligence: Technologies and Applications, 2016
Knowledge and skills students gather for a period of time is difficult to estimate. Learning is e... more Knowledge and skills students gather for a period of time is difficult to estimate. Learning is effected by a number of factors and prior knowledge is among the very important ones. Despite existence of a substantial amount of tests for assessing newly obtained knowledge and skills, there is still a need to provide tailored responses to answers students submit by connecting those answers to their prior knowledge. Lattice structures prove themselves to be especially useful for unveiling dependences among various factors.
Proceedings of the 2016 International Conference on Artificial Intelligence: Technologies and Applications, 2016
Students' knowledge assessment has occupied the attention of many researches pertaining to differ... more Students' knowledge assessment has occupied the attention of many researches pertaining to different disciplines. Recent areas of interest in this regard include availability of preliminary skills and status of latest obtained knowledge, selfassessment, grading methods, tests, hints, help functions, etc. Involvement of smart technology in assessment processes is another important issue which rapidly gains popularity among students and lecturers. What seems to have received less attention in earlier studies is a way to establish whether apparent lack of knowledge is related to intrinsic or explicit terms and concepts. Application of selected graphs is put forward in this work in an attempt to increase the likelihood of an improved knowledge assessment.
Proceedings of the 5th Wseas Congress on Applied Computing Conference and Proceedings of the 1st International Conference on Biologically Inspired Computation, 2012
In this paper we illustrate application of many valued context in the area of knowledge evaluatio... more In this paper we illustrate application of many valued context in the area of knowledge evaluation. While the classical binary approach clearly indicates relationships among objects and attributes it still does not provide any information on the degrees to which an object possesses an attribute. Many valued contexts allow inclusion of more detailed description on such dependences.
Proceedings of the 11th Wseas International Conference on Applied Computer and Applied Computational Science, Apr 18, 2012
Many educational institutions collaborate for developing joint bachelor, master and PhD programs.... more Many educational institutions collaborate for developing joint bachelor, master and PhD programs. Quite often in the process of completing learning materials, included in an intelligent tutoring system f. ex. they have to choose among different learning objects developed by different teams and originally intended to be presented to different type of students. In order to be effective this process should involve both content providers and IT experts. The objective of this paper is to show how a rough set theory based approach can facilitate the process of ranking available learning objects.
Ordering of humans preferences is a complicated process. In this paper we are exploring the prope... more Ordering of humans preferences is a complicated process. In this paper we are exploring the properties of symmetry groups for simplifying a readable graphical representation of orderings of preferences in a graph structure.
The authors of this paper have investigated t-error-correcting BCH codes over Z4. Such codes with... more The authors of this paper have investigated t-error-correcting BCH codes over Z4. Such codes with length ≤ 105 and dimension ≤ 13 have been constructed. They are described with their parameters and when Hamming weight and Lee weight are different corresponding generator polynomials are given. The generator polynomials are result of multiplication of primitive basic irreducible polynomials over Z4. Graeffe's method has been used for finding a polynomial whose roots are the squares of the roots of p(x) where p(x) E Z22[x] is a primitive basic irreducible polynomial.
The concept of Z4 - linear codes has proved to be successful to describe certain well known non-l... more The concept of Z4 - linear codes has proved to be successful to describe certain well known non-linear binary codes, for which the parameters are extraordinary good. In this paper we start an investigation of linear, binary codes, which are Z4, - linear, and the purpose is to find out to what extend the concept of Z4, - linearity is also relevant to describe linear, binary codes, which has optimal parameters. A number of examples are given and two basic structure theorems for the codes in question are formulated.
Proceedings of the 2015 International Conference on Modeling, Simulation and Applied Mathematics, 2015
Selection of an optimal knowledge assessment method appears to be a multiple criteria decision ma... more Selection of an optimal knowledge assessment method appears to be a multiple criteria decision making problem among many other things. There is hardly any doubt that working with humans knowledge is always done in the presence of uncertainties. It is also not a secret that a large number of experts in the field of knowledge assessment feel much more comfortable expressing their opinions and statements in linguistic terms and number intervals rather than with crisp values. In this work we address the problem of ranking alternatives for students' knowledge assessment. Interval number theory seems to be an appropriate approach to begin with, when considering the nature of such investigations. While the method is definitely useful for handling interval data it certainly does not indicate what two or more alternatives have in common. This type of information is often required when in real life situations the best theoretically proven alternative cannot be taken. Therefore we propose application of formal concept analyses on the same data in addition to the work performed with interval number theory. Combining these two methods can facilitate multiple attribute decision making processes where for some reasons outcomes of alternatives' rankings with interval numbers have to be reconsidered.