José Luis Galán-García

A portable knowledge-based system for car breakdown evaluation

A prototype of KBS for car breakdown evaluation to be accessed remotely using smart devices is presented.It uses a flexible algebraic inference engine that can be adapted for many-valued logics.The inference engine uses Groebner bases (of polynomial ideals).The execution is remote and completely transparent to the user.It allows drivers to obtain suggestions immediately when a breakdown occurs just using a smartphone. Modern cars have many dashboard lights and not all drivers recognize or know the importance of all of them. Red symbols usually indicate a safety issue or a serious problem, meanwhile yellow symbols use to indicate a not so urgent problem. Green and blue symbols usually provide information about the systems connected. But not all the red icons require of the same action, and the user manuals of most modern cars, with their sophisticated electronic systems, have hundreds of pages. Meanwhile, smart devices have become popular and have an outstanding computing power plus Internet connection. Consequently, the conditions for developing a knowledge-based system that helped the unaware driver in case a dashboard light went on, exist. The application should evaluate the situation and recommend the best actions to be carried out by the driver (regarding the possible repair on site or at a workshop, its urgency or even the need to immobilize the vehicle immediately). We have designed such a knowledge-based system and have developed a simplified one as example. A friendly Graphical User Interface has been developed in order to ease the communication with the application and its use in remote using any smart device with Internet connection.

An accelerated-time simulation of baggage traffic in an airport terminal

ATISBAT is a model for the simulation of baggage traffic in an airport terminal that will be introduced in this talk. This model is based on the GRAM model, first introduced at ACA’2011 (in the Nonstandard Applications of Computer Algebra session), that is detailed in the paper entitled An accelerated-time simulation of car traffic on a motorway using a CAS (to appear in the special issue devoted to this session of the journal Mathematics and Computers in Simulation). The algorithms involved in the ATISBAT model have been implemented in a Computer Algebra System. On the other hand, a Java application that shows the simulation graphically is being developed. Such an accelerated time simulation of baggage traffic can be used both as an aid during the terminal’s design process (in order to optimize the conveyor belt network’s topology) and for optimizing the use of an already built conveyor belt network. The graphic interface will produce important visual information about the simulation. This graphical approach is very useful, since the effects of making any change can be visually shown immediately.

Improving CAS capabilities: New rules for computing improper integrals

Abstract Different Engineering applications require dealing with improper integral on unbounded domains (improper integrals of the first kind). The classical way for solving these integrals is by means of elementary Calculus (antiderivatives and limit computations) or using numerical approaches. In both situations different problems can arise. For example: the non-existence of antiderivative, the corresponding limit does not exist or integrals depending on parameters which complicate the use of numerical approaches. In order to solve this situation, Advanced Calculus techniques, such as Laplace or Fourier Transforms and the Residue Theorem can be applied. A brief review of the corresponding theoretical frame is included in this paper. Computer Algebra Systems ( Cas ) are pieces of software that allow symbolic computations. Nowadays, there are many Cas in the market with an increasing level of sophistication which make them a very powerful tool in Engineering. In this paper, a brief review on the history of Cas evolution is introduced. In this work, some Advanced Calculus techniques for computing improper integrals of the first kind which cannot be solved with standard procedures are described. These techniques could be easily integrated in almost every Cas . However, we have detected some lacks of these techniques in many widely used Cas . In this paper, some tests involving improper integrals have been developed. These tests have been used to check the capabilities of some Cas and the results have provided a classification of the Cas with respect to this field. One of the main contributions in this work is the generation of different rules to compute improper integrals of the first kind. The rules have been classified in specific rules (those coming from the tests) and general rules (those coming from theoretical frames and generalizations of the specific rules). These rules are easy to include in a Cas increasing the facilities of the Cas in the field of improper integral computation.

A prototype of a RBES for personalized menus generation

Abstract People have many constraints concerning the food they eat. These constraints can be based on religious believes, be due to food allergies or illnesses, or be derived from personal preferences or dislikes. For instance, preparing the menus at a hospital can be really complex. Another special situation arises when traveling abroad or simply when eating at a foreign cuisine restaurant (it is not always enough to know the brief description in the restaurant’s menu or the explanation of the waiter). Therefore, we consider that it would be very interesting to develop a knowledge-based system that automatically obtained a personalized menu for each customer, according to the precise recipes of the restaurant and taking into account the data given by the customer and the ingredients out of stock (if any). Although there are many knowledge-based systems devoted to diabetic’s meals, diets, food supply chains, etc., we do not know of any comparable system. We have developed a rule based expert system that uses sets and lists for handling data and an algebraic inference engine. It has been implemented in the computer algebra system Maple.

A Geo[X]/G[X]/1 retrial queueing system with removal work and total renewal discipline

In this paper we consider a discrete-time retrial queueing system with batch arrivals of geometric type and general batch services. The arriving group of customers can decide to go directly to the server expelling out of the system the batch of customers that is currently being served, if any, or to join the orbit. After a successful retrial all the customers in the orbit get service simultaneously. An extensive analysis of the model is carried out, and using a generating functions approach some performance measures of the model, such as the first distribution’s moments of the number of customers in the orbit and in the system, are obtained. The generating functions of the sojourn time of a customer in the orbit and in the system are also given. Finally, in the section of conclusions and research results the main contributions of the paper are commented.

Genetic and Algebraic Algorithms for Classifying the Items of a Likert Questionnaire

A Likert scale is a psychometric response scale primarily used in questionnaires to obtain participants’ preferences or degree of agreement with a statement or set of statements. Respondents are asked to indicate their level of agreement with a given statement using an ordinal scale. Nowadays, Companies often use Likert surveys to discern the capabilities and skills of current or potential employees, asking multiple questions about each competency. With such a questionnaire, different competencies are evaluated and therefore, the result of a questionnaire will provide important information about capabilities and skills of the respondents. As an example, we will describe, for a real questionnaire, how to classify each question with the corresponding competency. That is, to find, for each Likert item, which competency is evaluated. We will present how to face and solve the problem using two different techniques: an approximate method, using a genetic algorithm and an exact algebraic method, solving a quadratic system of n equations and n unknowns. Finally, we will set the basics to solve this competency-assignment problem for a generalized version of similar questionnaires with n Likert items for evaluating m competencies. The advantages and disadvantages of both techniques will be also shown.

Partial differential equations based simulations in multiple space dimensions

• Computational electromagnetics and coupled problems, • Fluid–structure interaction and multi-phase flows, • Computational chemistry and quantum physics, • Computational civil and structural engineering, • Computational biology and bioinformatics, • Computational geometry and topology, • Mathematics Education and Outreach, • Hydrology and porous media flows, • Petascale and exascale computing, • Wave propagation and acoustics, • Climate and weather modeling, • GPU and cloud computing, • Uncertainty quantification, • Open source software.