Albert Fornells Homepage
N�ria Maci� » Research

Research

Dra. Elisabet and me are the responsables of the Soft Case-Based Reasoning area of the Research Group in Intelligent Systems from our university. Our research line focus on the integration of Soft-Computing techniques inside Case-Based Reasoning (CBR) systems to promote the CBR performance in terms of accuracy and computational time.

[-] What are Case-Based Reasoning systems?
[-] Why Soft-Computing techniques are usefull?
[-] Our Soft Case-Based Reasoning research lines
[-] Research & Development projects
[-] Applications domains
[-] My personal research lines

Don’t hesitate to contact to me if you want to get further information about some issue.

———————————————————————————–

[Top] Case-based reasoning (CBR) systems solve new problems through an analogical procedure based on experiences represented by a set of cases stored in a case memory. As the case memory feeds this process, its size and organization plays an important role in the CBR performance in terms of computational time and accuracy. This is especially critical in real world problems because most of the them deal with a huge amount of data, which are often unreliable and uncertain. This is due to the fact that reality is always complex and, moreover, it may be partially unknown. Therefore, the features of the aforementioned domains (e.g. melanoma cancer) may negatively affect the cases recovery in the case memory:

[-] The uncertain cases may confuse the system. This issue may be critical in applications in which the error cost is high. For instance, in medicine, the error cost may be a human life.
[-] The response time may be slow if there are a lot of cases. This aspect may be critical in real time applications in which a high response time in needed.

Procedure of solving a problem using the human reasoning

———————————————————————————–

[Top] We focus on introducing the capabilities of Soft-Computing techniques like Fuzzy Logic, Neural Networks or Evolutionary Computation among others inside CBR to enhance its performance. These techniques are featured by allowing a better management of this kind of imprecise and complex knowledge than traditional hard computing techniques. Thus, we tackle the last issues and the CBR performance is improved.

Promoting the CBR performance through the integration of Soft-Computing techniques

———————————————————————————–

[Top] Our  Soft-CBR  research lines are divided in four interrelated goals:

1) Organization of the CBR case memory through Soft-Computing techniques like Self-Organizing Maps, Evolutionary Computation or Fuzzy Logic.
2) Helping experts to understand why a solution is proposed.
3) Combination of multiplesource experiences to improve the reliability of the solution.
4) Development of data mining tools like plugins for jColibri framework, ANALIA or for the management of the melanoma domain.

———————————————————————————–

[Top] The research activity of the area is mainly focused in the MID-CBR project (TIN2006-15140-C03-03) leaded by Dr. Enric Plaza. The goal is to define an integrative framework for the development of case-based Reasoning systems. The team project is composed by researchers from IIIA research center belonging to the Spanish Council for Scientific Research (CSIC), from  GAIA at Complutense University of Madrid (UCM) and from us.

The main objectives of the project can be summarized as follows:

1) new ways to use techniques of soft computing for CBR,
2) techniques for case reuse of a declarative and generic nature,
3) techniques for case retrieval in knowledge-intensive CBR systems,
4) integrating ontologies both in CBR systems and retrieval and reuse techniques,
5) maintenance techniques both for case bases and for CBR systems capable of dealing with issues arising from design, implementation, and deployment of industrial strength CBR systems,
6) the empirical evaluation of the developed techniques by means of CBR prototypes implemented for several experimental domains, and
7) developing component-based software platforms to support CBR systems development.

CBR applications according to the type of knowledge

———————————————————————————–

[Top] Our research is mainly focused on three application domains: Melanoma cancer diagnosis, detection of vulnerabilities in telematic networks and education.

Melanoma cancer diagnosis

Skin is mainly divided in three layers as picture shows. The lowest part is called dermis and it contains cells called melanocytes responsible of the production of melanin, which give the skin pigmentation. Melanoma cancer appears when melanocytes turn cancer cells, it means, they are able to invade other organs because they grow and reproduce in an uncontrolled way. Althoug it is not the most common skin cancer, it is which causes most deaths. This increase, caused by solar habits, makes crucial the early diagnosis, even more if we analyze that this cancer is mortal in approximately 20% of cases and prompt diagnosis permits practically a secure regain.

One of the most used techiques to the diagnosis of melanoma is the ABCD rule which considers four clinical features commonly observed in this kind of tumour: asymmetry, border irregularity, colour variegation, and a diameter larger than 5 mm. Although most of melanomas are correctly diagnosed following this rule, a variable proportion of melanomas does not comply with these criteria. The current procedure when a suspicious skin lesion appears is to excise and to analyse it by means of biopsy. Commonly, the result of the biopsy allows to determine the accurate malignity of the lesion. For this reason, we work with experts from the melanoma unit at the Hospital Clínici Provincial de Barcelona in order to help them to improve the early diagnosis and avoid unnecessary byopsis.

Melanoma is the most dangerouse skin cancer, and we work on helping experts to improve the early diagnosis

Detection of vulnerabilities in telematic networks

Nobody conceives a competitive organization without all its resources interconnected and continuously available. As organizations have become increasingly dependent on their networks and Internet, they have also opened themselves up to potentially immense risks and vulnerabilities. Consequently periodically audits and vulnerability assessments are needed to detect and eliminate these possible security holes. Vulnerability assessment is the process of identifying and quantifying vulnerabilities in a system or a network. However, time and cost can limit its depth. These limitations justify the automation of the processes involved in a vulnerability assessment, especially those related to the analysis of test results, as a thorough network security test generates large data quantities.

We collaborate with security experts from ISECOM and with experts from the telematic department of our university.We focus on helping experts to speed up and improve the reliability of their security diagnosis by tackling this problematic through the development of two crucial tasks:

1) Network testing. CONSENSUS is a tool developed for gathering data related to vulnerability aspects from computer.
2) Analysis of testing results. ANALIA is a tool developed for helping expert to analyse and diagnose the level of vulnerability of new computers.

Telematic security has became a crucial issue in all the organizations

Education

Nowadays the educational methodologies are being reconsidered to allow the successful achievement of the skills of the future computer engineer due to two issues. On the one hand, the evolution and the use of new technologies require the redefinition of the new skills for the future IT professionals. On the other hand, the educational models are being reconsidered and focused on the concept of competences as a basis for learning outcomes around the world.

La Salle from Ramon Llull University obtained at 2006 the European acknowledgement European Credit Transfer System (ECTS) Label and the Supplement Label Certificate. This was the results of adapting their university graduates according to the new educational models, it means, the expected competences acquired by the student in each subject were specified. We focus on helping La Salle in assessing the acquisition of the specified competences in the ECTS Label for each subject. The experts analyze the relationship between competences and subjects through two steps: (1) identify subject typologies according to the evaluation methods used by educators and, (2) identify the relation of these methods with the competences.

———————————————————————————–

[Top] Although I like all the reserach lines of the Soft CBR area, my personal research line mainly focuses in the continuation of my PhD thesis, it means, about the organization of the case memory to improve the CBR performance.

I graduated from the Universitat Ramon Llull with a PhD in information technologies and its management in 2007. My thesis, entitled ‘An integrative framework of the knowledge discovery and soft-computing capabilities of Self-Organizing Maps in the Case-Based Reasoning‘, basically analyzed how to promote the performance -in terms of accuracy and time- of Case-Based Reasoning (CBR) systems through the organization of the knowledge using a Self-Organizing Map (SOM). Therefore, its hybridization allows to take profit of  the SOM capabilities to discover useful knwoledge for organizing the CBR case memory and, consequently, improve its access. I had the privilege of having as members in my PhD comitee researchers as Dr. Enric Plaza, Dra. Eva Armengol, Dra. Ester Bernadó-Mansilla, Dr. Belén Díaz-Agudo and Dr. Jordi Freixenet, and Dra. Elisabet Golobardes as PhD supervissor. Finally, the core of the PhD thesis was developed inside the MID-CBR project. You can download the Phd thesis here.

SOMCBR improves all the CBR lifecycle

Nowadays my research is mainly focused on clustering algorithms and, more specifically, in evolutionary multiobjective clustering algorithms. This approach uses the searching capabilities of evolutionary algorithms for building a Pareto set of solutions, where each one is a possible organization based on the relevance of objective. Thus, this capability of sorting solutions according multiple criteria opens a door for modelling the case memory according to our needs. This amazing topic is the research line of my PhD Student Alvaro Garcia-Piquer.

All the software related to the PhD thesis has been integrated in the jColibri 2.0 framework through the plugin Thunder. jColibri 2.0 is one of the leading open source software in the CBR community, which has been mainly developed by my friend and collegue Dr. Juan Antonio Recio-García. You can download it from the project homepage. If you try, I’m sure you will use it due to all its functionalities.