Applied Computer Sciences in Engineering

In Micro and Small Companies for Software Development (MSCSD) of Mexico, the knowledge is generated in each software project. So, it is possible to transform tacit knowledge into explicit, to have some strategy and data storage device. Note that, when the knowledge exists only in the brains of developers there is the disadvantage that, when a developer leaves the organization, knowledge is lost. Therefore, it is possible to transform the tacit knowledge into explicit, if exist some strategy and data storage device. Developers need to generate and storage knowledge in any device and format to process, storage and exploit. In this paper, it has been called knowledge asset to an idea or solution processes or software development activities, which may be embodied as text, images, audio or video.A novel model for knowledge management is proposed that defines how must obtain, process, store and exploit knowledge resulting in the México’s MSCSD. The conclusion is that it is necessary to implement politics and processes in MSCSD to promote knowledge management and that must change the culture in organizations.

Formal effort required to specify and analyze architectures using formal languages is high. This has motivated us to build a software tool that allows the interpretation of component-based software architecture described using $$\rho _{\mathrm {arq}}$$ calculus. This tool offers the display facility to architects on a graphic way the structure and the architectural execution flow described in the formal expressions under study. For the development of this software tool some different modules were considered, altogether, they interpret expressions in accordance with the syntax and the operational semantics of the $$\rho _{\mathrm {arq}}$$ calculus; in addition, the tool maps the formal expressions to UML 2.x notation graphic elements. In this way, the application displays the architectural configuration using a visual modeling language(UML components) while showing the architectural execution flow by highlighting the provision interfaces when a $$\rho _{\mathrm {arq}}$$ calculus rewriting rule is executed. The $$\rho _{\mathrm {arq}}$$ calculus use is simplified with this. The architectural analysis tasks will be easier and the architect could focus on the architectural behavior and not on the calculus itself.

Software reuse in the early stages is a key issue in rapid development of applications. Recently, several methodologies have been proposed for the reuse of components, but mainly in code generation as artifacts. However, these methodologies partially consider the domain analysis, the business modeling, and the reuse through of components. This paper introduces a metaprocess-oriented methodology based on reuse it as software assets starting from specifications and analysis of the domain. The approach includes the definition of a conceptual level to adequately represent the domain, a reuse process to specify the metaprocess as software assets, and an implementation level which defines the rules for conceptual level and reuse of metaprocess. The methodology has been applied successfully to the first phase, i.e. at the specification of the conceptual level in the field of e-health, in particular in monitoring system of patients with cardiovascular risk, but our work has advances in reuse of models for implementation in other contexts contributing to productivity in software development.

During last decades, there has been concern on organizing the information in order to make it more understandable. Many organizations are focused on providing a better classification in such a way that information will be understood by humans and allow a rapid access to resources. This article is intended to present a proposal to strengthen the uses of virtual reality based on simple knowledge representation schemes, in order to provide an environment for navigation through concepts of a given knowledge area that will enable a virtual learning environment. Finally, outcomes from this survey are presented by TAM testing in order to perform validation mechanisms for the proposal.

The present paper seeks to socialize the understanding brought about by the investigation of the processes of appropriation and use of information and communication technologies in the educational field of engineering, at a private University that offers in-class education in Latin America. This study is carried out in a context of complexity called “information society and knowledge”, interweaving related fields (called dimensions), such as education, communication, information technologies and subjectivity. The article presents results of the imaginaries of the information society that the actors (students and teachers of a Faculty of Engineering) have of the appropriation, recognition and measurement of the information and communication technologies in its educational events. The analyzed results correspond to the relationships between information society, knowledge and education.

In this paper, the performance of the IRBASIR-Imb algorithm (Induction of Rules Based on Similarity Relations for Imbalance datasets) is used in a classical task in the branch of the Civil Engineering: predict if structural failure depends on the connector (canals) or concrete capacity of connectors. The use of similarity relations allows applying this method in the case of mixed data (features with discrete or real domains). The experimental results show a satisfactory performance of the IRBASIR-Imb algorithm in comparison to others such as C4.5.

This paper presents the use of Deep Belief Networks (DBN) for direction forecasting on financial time series, particularly those associated to the High Frequency Domain. The paper introduces some of the key concepts of the DBN, presents the methodology, results and its discussion. DBNs achieves better performance for particular configurations and training times were acceptable, however if they want to be pursued in real applications, windows sizes should be evaluated.

Data mining schemes, or workflows, are collections of interconnected machine learning models, including preprocessing procedures, and ensembles methods combinations. The proposal of data mining schemes for a task at hand has always been a task for experienced data scientists. We will study generating and testing workflows by automated procedures. Two representations of data mining schemes are used in this paper – a linear one, and a one based on direct acyclic graphs. Efficient procedures for generating schemes are presented and evaluated by testing the generated schemes on real data.

The generation distributed systems are a good alternative for the reasonable use of energy. Moreover, neuronal networks are an appropriate option for modeling and control of nonlinear complex systems. The eolian energy has shown to be an alternative for electric power generation, even though it also presents limitations for proper management due to associated variations to weather conditions which affect wind speed. In this paper, considering the characteristics present in wind power, neuronal and neuro-fuzzy systems are suggested for the prediction of wind velocity associated whit wind power. The results show an adequate performance of neuro-fuzzy systems for forecasting of wind speed.

The development of vision systems to plant leaves identification from images is a very important current challenge. One of the main lines of research is the improvement in performance. The performance of automatic identification systems is directly linked to the extracted features. The extracted features allow to identify or classify the object. However, sometimes a high number of features introduces noise which affects the performance. In this research, a genetic algorithm is proposed to extract the most discriminative features. The proposed technique reduces the dimensionality of the data set and improves the performance to identifying plants. In the experimental results, the proposed method is compared with feature selection classic techniques. Experimental results show that the proposed technique obtains a significant improvement in the performance in comparison with other techniques.

This paper presents an algorithm for initializing the weights in multilayer perceptrons based on the new metrics called Fuzzy Similarity Quality. The new metric used a binary fuzzy relation for quantify the strength of the similarity between two objects. This measure computes the grade of similarity in a decision system in which the features can have discrete or continuous values. Experimental results show that the proposed initialization method performs better than other previously reported methods to calculate the weight of features.

This work presents a power converter prepared to easy modify its electrical connections in order to obtain all configurations possibilities of the cascaded multilevel power converter with four H-bridges. Allows to implement both sub-topologies: single CD source and separate DC source, with symmetrical and asymmetrical configurations until 81 voltage levels. All the modifications can be performed using a graphical user interface develop in Matlab®. The modulations are optimized using a genetic algorithm and the system control is a FPGA. The power converter was developed mainly to performing power quality analysis.

Courier services consist generally in distributing packages or envelopes that are received daily for a set of customers geographically distributed through a fleet of vehicles. Thus, these services could be modeled as vehicle routing problem. The aim of this paper is to show an approach to solve this problem. We propose a three stage approached the first ones consist of scheduling, the second one is a clustering of customers, and the last one is a routing stage. Finally, we presented numerical results using a case study.

Service desks over the years have become an integral part of most businesses, whether telecommunications, industrial, banking, health, etc. That is why today the management of these companies face major challenges such as the proper planning of the agents, skills, processing times, breaks etc. For those major challenges, simulation is suitable for modeling the service desk.This paper presents an application of simulation for the service desk of the oilfield services company in order to achieve better system performance and improve the customer service process. The name of the company will be anonymous due to security policies.

One of the most exported fruit from Colombia to Europe has been Uchuva, given its exotic character, taste and nutritional content [1]. Due to the importance of this product for Colombian exports of fruits and the latest trends in transport, this research studies the impact of using multimodal transport over the logistics performance food supply of Uchuva using the system dynamics approach. The model was built in Ithink, and it provides a configuration of the Colombian fruit supply chain, considering aspects such perishability of the fruit, logistics and environment. The indicators studied are: transportation costs, total time of transport, losses of food due transport and inventory, and CO₂ emissions caused by the transport mode.

Given the current nature of electronic fraud prevention, there is a demand for high-quality and prompt customer service. These organizations must design well thought out strategies for improving customer service, especially with regard to reducing attention times, as any delays can lead to a higher level of fraud losses. With this in mind, organizations must develop a Shift- allocation proposal based on multiple criteria. The criteria must be validated through simulation techniques that permit optimizing two performance metrics: waiting times and costs.

This paper presents the design, conceptualization and implementation of a multi-agent system which solves dynamically the caregivers’ routing problem accepting new requests when the system is already running. To do so we propose a multi-agent approach that allows to simulate a home health care system using a mixed integer programming model to better make the routing schemes of the caregivers. The approach was implemented in the Jade middleware, was tested in multiple scenarios changing the numbers of caregivers, the length and the numbers periods of simulation and finally numerical results for the simulations are presented.

Activated carbon has multiple uses both to meet industrial needs as domestic. This grow in the demand has allowed Colombian industry to look for organic sources for obtaining it. Tecsol has advanced more than 20 years of research on this field. Today, they want to turn their pilot plant used in research projects to turn it into an industrial plant. This requires ensuring the supply of organic material such as using ovens at maximum capacity. As this is a new system, it should estimate the sales potential and then determine the best logistics parameters. The developed model uses continuous simulation based on the Forrester model. The industrial dynamical model determines a trade-off between different manufacturing resources and its impact on financial results. Its implementation in IThink can respond to many different questions about the main logistic components changing over time.

This paper studies a knowledge-based expert systems for the scheduling problem in service systems. We establish some differences between manufacturing and services systems in order to identify the aspects that influence in the scheduling process. We review the main techniques to solve the scheduling problem related with classical methods, metaheuristics, artificial intelligence and knowledge-based expert systems approaches. Finally, we propose a structure of knowledge-based systems in order to solve the scheduling problem in services systems. We apply our approach in a health service system in order to show the setting and the results of our knowledge-based expert system.

In this paper a simulation of a basic model of multiple swarms of particles is presented, illustrating the behavior of the coffee berry borer infestation in Colombian coffee crops generating information. In regard of this problem it is used engineering techniques, which aims to promote impact of the level at which the pest harms the national economy. The results show an adequate performance of the model and simulation proposed.

The following article shows the implementation of fuzzy logic controllers Type-1 and Interval Type-2, designed firstly for a diesel motor and implemented on a nonlinear second order system. Additionally, another way of implementing the Type-2 fuzzy logic controllers, is shown, using Kleene algebra, due to its benefits during the implementation of a simple function. Likewise, a variation is performed where a type reduction is applied to an algebraic expression. Finally, it is desired to observe the behavior of the controllers given the uncertainty sources.

This paper presents a uncertainty measure of an Interval Type-2 fuzzy set based on its Footprint of Uncertainty. The proposed measure provides information about the amount of uncertainty contained into an Interval Type-2 fuzzy set. Some relationships between the proposed measure and other well known measures of an Interval Type-2 fuzzy set as the centroid, variance, cardinality, etc. are defined and illustrated through some application examples.

In this paper we analyze some cases where the Soft Constraints of a fuzzy LP Linear Programming model can be changed, which is known as Sensitivity analysis. Other related properties are also glimpsed and discussed in order to see how this model is sensible to changes in the parameters in their constraints. Some examples are provided and the results are discussed.

This paper presents a model for solving probabilistic travel distribution problems that involves fuzzy uncertainty. Using entropy measures for interval-valued problems, we extend those results to a fuzzy environment via extension principle and nonlinear mathematical programming methods. An application example is solved using the proposed fuzzy entropy method in order to analyze their results.

Traffic lights costs 0.5% of the gross domestic product (GDP) of the city due to heavy traffic, so multiple actions are being carried out to reduce this indicator and mitigate its effects. However, although Bogotá currently has around 1.400 signalized intersections, the importance of traffic lights in mobility is still vital. Besides technological change, city policies, preventive and corrective maintenance of traffic lights, this paper presents a study of power quality and harmonics analysis in traffic lights focused on the quality of the devices used, not from phenomena coming from the electrical network. Full LED lights, turn arrows, pedestrian and green halogen lights are tested over a special module to measure harmonic distortion and power factor before recommending THD levels for them.

This paper describes the design and implementation of a Supervisory, Control & Data Acquisition (SCADA) system dedicated to realize on-line visualization and long-term monitoring of the performance of a single-phase single-module photovoltaic grid-connected installation. The main objective of this development is to ensure continuous monitoring of the efficiency and relevant power quality indicators of a two-stage microinverter providing a comprehensive treatment of the electrical variables. The system consists of a software component developed in LabVIEW and a hardware component including specialized sensors and analogue electronics. Both components communicate synchronously through an acquisition card, which enhances visualization and accuracy of computations. The mathematical expressions employed to obtain variables and indicators are listed, explained and verified by means of simulated results.

Distributed maximum power point tracking (DMPPT) circuits are useful to improve the power production of photovoltaic (PV) systems operating under mismatched conditions such as partial shading. The main option to implement DMPPT circuits is the series connection of PV systems based on dc/dc converters, however those converters are subjected to overvoltage conditions that could damage the circuit. This paper proposes a sliding-mode control technique to avoid overvoltage conditions, which ensures the circuit operation in a safe operating point.

This paper presents a comprehensive study of the digital implementation of the control requirements of the output stage of a two-stage solar microinverter. This approach uses a synchronized nested-loop controller which ensures the tracking of an internally generated high-quality current reference, the estimation and cancelation of the effect of the DC-link voltage ripple in the control loops and the regulation of the average value of the DC-link voltage. The proposed control architecture is validated by means of simulation results comparing operation of the inverter using continuous time, quasi-discrete time and discrete time implementations.

Searching for solutions to cope with the increasing demand of bandwidth in communications networks, the approach of sending Radio Frequency (RF) signals through optical fiber has raised as a potential solution to this issue. Such architecture is known as radio over fiber system (RoF). In order to enhance these kinds of systems, it is necessary to improve the optical reception to efficiently detect both signals (baseband and RF). This paper presents the summarized results of the comparative study of three optical filtering schemes: Fabry-Perot filter, Fiber Bragg Gratings (FBG) and Sagnac interferometer through the analysis of the Bit Error Rate (BER) obtained by simulations.

The paper focuses on the design of an open telematics architecture for telemedicine linked to a mobile ubiquitous device, a standalone device with direct connection to the cellular data network LTE (Long Term Evolution). The device when developed allows a multiplexing of biometric readings through adaptation of specialized Sensors and distributed in different parts of the body, which allow mapping the vitals signal: level of glycemia, Body Temperature Sensor, Blood Pressure Sensor, Pulse and Oxygen in Blood Sensor (SPO2), Airflow Sensor (Breathing), Galvanic Skin Response Sensor (GSR - Sweating), Electrocardiogram Sensor (ECG) and Electromyography Sensor (EMG). The system’s modem (TELIT Le910) allows obtaining geo positioning signal of each patient in real time through GPS positioning GLONASS system. This set of data is sent and stored to a geographic health information system, where there is a specialized middleware for a geo-referencing related in real time with those specialized health services and their physical infrastructures. A whole technological system that allows to take advantage of the services 4g and the geographic information systems of health monitoring care of patients with chronic diseases in Colombia, where there are some remote areas and difficult access.

In modern economies it is essential a proper system of transport that enables population mobility and consequent accessibility to services. However, its current configuration is causing strong negative externalities and generates much of the problems of environmental, social and energetic sustainability. The changes required by the current unsustainable configuration have to be based on a new vision of transport and on the development of theoretical and empirical criteria that enable the creation of sustainable transport systems.The purpose of this study is to analyse the most important factors of urban mobility in its current configuration, but not only the mobility of passengers but of all the elements of mobility in urban environments. Externalities caused by transport have been analysed, and the necessary principles to develop a model to aid decision-making regarding the modal split in a city have been developed.From a holistic view, it has been developed an analytical model based on methodological support obtained from the technique of multi-criteria analysis AHP (Analytic Hierarchy Process), with the aim of achieving user satisfaction, sustainable growth and energetic and environmental efficiency. The construction of the model has allowed to analyse the sensitivity and robustness of the AHP, so as to obtain the classification of attributes with respect to an ideal situation, but also the most appropriate modal split of alternatives with respect to the various evaluation criteria. As operation check of the functioning made by the model, a methodology in a case study with different characteristics has been applied.

The rise of the software development methodology known as Model-Driven Engineering, has allowed the many advantages of its use to be observed, while meeting the main objective of increasing a company’s profitability through an effort in software development. In the short-term it increases productivity by raising the value of first software artefacts; long-term it helps to avoid the obsolescence of primary objects of the software [1]. This way, compatibility between systems increases, the design process is simplified and communication, both among individuals and among teams working within the system, is fostered. It is for this reason that the development of a web application named OcioColombia, under the Model Driven Architecture (MDA) methodology, has been carried out. By doing this, the objectives achieved in each of the architecture’s stages can be shown; the benefits offered by the methodology can be exposed and finally, different software tools are able to be orchestrated into an application that allows the user to search for entertainment events and tourist locations available in Colombia.

This paper describes a way to measure the development and evolution of technologies implemented and managed by the Ministry of Information and Communication Technologies in Colombia, through the use of tools of a quantitative nature where the process that a technology has had in years and how profitable it was for that administration is represented in graphs of analytical use, as well as the different comparisons that can be made with different countries by technology developers, technology consumers and/or emerging countries. At the local level, this analysis is made on the basis of different reports of implementation of technology produced by the different government reporting entities.

This article discusses the needs and requirements of a mobile application oriented to the graduates from higher education institutions, taking into account the communication established so far in these institutions, the benefits offered by the special applications development for the interaction of between the different communities and the interests that may have the graduates of universities related to their alma mater. For this, there will be a preliminary outline about the architecture that implementation would require for their development, taking into account the needs of users and the viability of infrastructure resources; next to this improvements may be possible about the graduates quality of life and opportunities to develop in the future new utilities in this application.

This paper presents the application of a second order sliding mode observer based on the classic super twisting algorithm in order to estimate the specific growth rate in a model of fed-batch bioprocess. This observer estimates the specific growth rate without assuming a specific model (such as Monod or Haldane), using the biomass concentration measurement. The observer allows the fixed time estimation of the specific growth rate, and provides robustness against uncertainty and parametric changes.