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Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A suitable design of manufacturing facilities can increase the efficiency of a company's internal operations by optimizing material handling and flow costs. This paper addresses the facility layout planning problem (FLP), modeled as a quadratic allocation problem (QAP), applied to a company dedicated to the production of liquors. The problem was solved using the Computerized Relative Allocation of Facilities Technique that belongs to the heuristic algorithms, which allowed us to determine the best allocation of the departments, considering the distances traveled and the material flow costs. Subsequently, a simulation was carried out to evaluate the new distribution given the company's daily activities, considering the variability of loading and unloading times. The simulation results suggest that, if the new layout is implemented, material flow costs and times would be reduced by 13.22 % and 4.28 %, respectively. [ABSTRACT FROM AUTHOR]

The objective of fringe pattern analysis is to extract modulated experimental information in an image. Among the techniques used in the demodulation process is the Regularized Phase Tracking. In this technique, a functional is proposed which is usually solved with classical minimization methods. This paper presents a minimization method for this technique using the fixed-point technique, which presents a normalized error like classical minimization methods, but with a notable reduction in processing time. [ABSTRACT FROM AUTHOR]

Copyright of Lámpsakos is the property of Fundacion Universitaria Luis Amigo, Facultad de Ingenierias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Visión Electrónica is the property of Fondo de Universidad Distrital Francisco Jose de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ingeniería Industrial is the property of Departamento de Ingenieria Industrial, Universidad del Bio-Bio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The agave is a source nontimber species, which can be used for the extraction of cellulose. Work has been done reporting papermaking fibers from six species of agaves: A. lechuguilla, A. angustifolia, A. tequilana, A. American., A. mapisaga and A. salmiana using different methods for extraction fiber. Their results indicate that A. mapisaga and A. salmiana were the species that showed better characteristics for the possible development of paper. In this paper we sought to create a new value added to the waste leaves Agaváceas agribusiness processing of pulque, from A. salmiana B. Otto ex Salm. Pulp was obtained by two methods: alkaline pulping method known as Organosolv. Characteristics and efficiencies of the processes under an optimization study were evaluated. As a result, it is concluded that optimal and reproducible for cellulose pulp by alkaline pulping A.salmiana conditions were: [NaOH] 12%; 24 hours; [Na2CO3] 2.5% and [Na2SO4] 0.2%. In contrast to the acid pulping optimum conditions they were: 60% H2O; 6 hours; [CH3COOH] and 80% [HCl] 0.5%. On the basis of response analysis "more better performance" in the ANOVA, we found that for the alkaline pulping, the factor having the greatest impact on the process is time and the factor that has lower incidence [Na2CO3]; on the other hand, for acid pulping the factor having the greatest contribution it is [CH3COOH] and the lowest incidence is the stirring rate. In the alkaline pulping confirmatory experiments yield 39.69% cellulose pulp A.salmianawas obtained whereas for organosolv pulping yield 71.57% was obtained. [ABSTRACT FROM AUTHOR]

This paper analyze the most significant studies done globally of the efficiency measurement on higher education institutions (IES in Spanish), which for this purpose use Data Envelopment Analysis. Within each study the characteristics considered are: selected model, model guidance, inputs and outputs, main findings, conclusions and the use of a complementary method. Models and characteristics studied in the papers are statistically analyzed, highlighting patterns used by most authors. Results are expected to be useful to provide a basis for future research on how to assess the efficiency measurement and productivity indices through this methodology. As a conclusion, DEA has been extensively used to measure the efficiency of education globally, 254 input variables were identified and divided into four categories and 230 output variables were identified and grouped into three categories for analysis. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia y Educación (2707-3378) is the property of Duanys Miguel Pena Lopez and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios Gerenciales is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction-- A mathematical model for flexible electrical loads and energy storage system scheduling is presented in this paper, leveraged by the hourly rates according to resolution CREG 015/2018 and analyzed at the residential sector in the context of new demand curves resulting from measures against the COVID-19 pandemic. Objectives-- Three mathematical optimization models are proposed, aiming to find the lowest billing cost for the end-user through flexible load characteristics and seeking optimization through mixed-integer linear programming models. Methodology-- For the calculation of hourly rates, the mathematical formulation described in resolution CREG 015 is implemented and hourly rates are obtained in three different levels following a logic similar to the demand response schemes called Time of Use. Results-- The results obtained show that a demand response program with hourly rates effectively introduces an economic incentive during the evaluated period, through the possibility of modifying consumption patterns that reduce the payment of the electricity bill. Conclusions-- The proposed model of energy demand through scheduling selected flexible loads model and the opportunity to use the energy stored in electric vehicles generates economic benefits for the user by minimizing the cost of energy during the teleworking period in COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Copyright of Boletín de Ciencias de la Tierra is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ingeniería Industrial is the property of Departamento de Ingenieria Industrial, Universidad del Bio-Bio and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios Gerenciales is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mathematical Model of a Series-Parallel (SP) photovoltaic (PV) generator represents each module through an equivalent electrical circuit denominated single diode model, this model has associated a nonlinear equation system that describes the electrical behavior of SP generator. This paper presents a solution of this system using optimization methods widely using: Trust Region Dogleg and Particle swarm optimization (PSO) for solving the electrical model of PV generator operating under homogeneous or non-homogeneous conditions, changing the number of submodules and shading pattern. It has been made simulations about generators composed by 3 and 15 series submodules, operating under different partial shading conditions. Between the implemented methods, Trust Region Dogleg show a better performance than other methods, with 2 and 14 times less computation time than the reference method and PSO, respectively, and a RMSE equal or 50% lower than PSO. [ABSTRACT FROM AUTHOR]

After a large-scale blackout power system restoration must be accomplished as soon as possible. For this, the generation must be initially restored, then, the transmission system, and finally the load pick up must be completed. To obtain a faster restoration process, it is necessary to establish start-up methodologies for generating units that first start those units that provide black start, and then take the starting power to other generation units without this characteristic, by means of a feasible transmission route. This paper presents a review of different methodologies of optimal generation start-up for power system restoration reported in the scientific literature taking into account the integration of non-conventional renewable energy sources. Within this review it is highlighted that heuristic methods, despite of being effective, are not used in real-time operation due to their high computational cost. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Facing an hypothetical, but increasingly, case of default risk on a mortgage or a fall in interest rates, an important issue raised by the borrower is the possibility of minimizing that risk by selecting the best refinancing option. In this paper, a mortgage refinancing model is presented, developing a purely quantitative programming method with a simulation based on an algorithm created especially for this case and that can be useful for mortgage debtors. Thus, we begin by explaining the theoretical basis on which the research is based, to proceed to develop the problem, continuing with its implementation. Finally, the results are analyzed and the most relevant conclusions are commented. [ABSTRACT FROM AUTHOR]

Proper management of projects has become an element of vital importance for the solution to problems of society. In this context, there are two main objectives to be solved: the construction of project plans which may comply with the constraints of the problem and the optimization in terms of cost and time of those plans. To this end, all activities of project must be organized in such way that the constraints related to the precedence among them and the availability of renewable and non-renewable resources at each instant of time are met. The aim of this paper is to present an Estimation of Distribution Algorithm (EDA), which incorporates the handling of the constraints in the probabilistic model, for the construction of optimal or quasi-optimal project plans. For the validation of the algorithm, authors used both the PSPLib database repository for the development of the scheduling research and the databases of projects of the Repository for Research in Project Management, University of Infomatic Sciences. [ABSTRACT FROM AUTHOR]

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Vínculos is the property of Revista Vinculos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an optimization procedure for identifying the minimum cost of water pipe networks considering a table of commercial diameters. To this end, a real-coding Genetic Algorithm (GA) with the use of a simulated binary and convex crossover and mutation per variable; as well as a dynamic penalty strategy was developed. A computer program to solve the hydraulic model based on the Newton-Raphson method was developed for calculating the head loss using Hazen-Williams (HW) and Colebrook correlations. By analyzing a benchmark pipe network example, it is shown that different results are obtained by the HW and Colebrook correlations. Moreover, when simulating the best HW pipe network configuration with the Colebrook correlation, some constraints of the design are violated, indicating that the Colebrook formulation is more adequate to be used in conjunction with the GA due to the randomness of the GA with respect to the Reynolds numbers. [ABSTRACT FROM AUTHOR]

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Characterizing physical phenomena existing in rotodynamic pumps has open a new field of study for these machines, where the efficiency on the operating point is being investigated, without significantly affecting other parameters. Research in the peripheral pump made have experimentally proved that Euler's equation does not model its hydraulic behavior because of the toroidal flow that is developed on them, which causes flow recirculation. Due to the above points, this paper develops a methodology for modeling the behavior of peripheral pumps, using a new criterion that was developed for predicting the characteristic curve of the pump and it is based on Euler's equation, which includes two correction factors. The proposed model was validated experimentally to verify that it describes the phenomenon according to the mechanical, geometrical and hydraulic variables involved of the pump. An optimizing process was realized using the corrected Euler's model, and the results are compared to actual pump curve thus is proved that the obtained hydraulic power is improved. The previous statement will allow predicting the gain on the performance of peripheral pumps without realizing expensive experimental test. [ABSTRACT FROM AUTHOR]

A container terminal is a source of dissimilar math problems and computational nature thus. In particular stacking of containers on the yard of a maritime terminal is one of the most important operations, mainly due to bottlenecks that arise therein, with the respective defaults efficiency indicators. Container stacking is divided into operations of loading, unloading and premarshalling. When these activities are performed operators and managers must determine the exact positions for containers, download or reposition making efficient use of available storage space, reducing unproductive movements and transportation costs, etc. The purpose of this paper is to review and describe objective functions found in the literature on optimization problems that arise during the stacking of containers operations. The analyzed objective functions are grouped into two basic classes: minimize unproductive movements yard cranes and minimize cost of transportation of containers during stacking. Finally, we discuss different items that could be considered as further research lines for mathematical modeling in container stacking optimization problems. [ABSTRACT FROM AUTHOR]

In this paper, we study facility location problem under many optimization criteria, as minimize the probability of failure and the supply chain total cost. We incorporate account transportation costs, consolidation center cost and reliability of the supply chain. The approach is to design robust supply chains that will be able to absorb negative impacts caused by disruptive events, such as hurricanes, twisters, earthquakes, strikes, accidents, among others. We provide a nonlinear integer-programming model that determines the optimal location of facilities under the criteria of cost and reliability. The proposed model was validated with data obtained from a supply chain of agribusiness sector of Atlantic department in Colombia. The numerical results show an improve of 9.5% in the reliability with an increase of 9.8% on transportation total cost of the supply chain. However, in the proposed model, the companies would not have to incur adequacy costs of consolidation centers, given that current facilities have the capacity to become consolidation center without incurring on significant costs [ABSTRACT FROM AUTHOR]

This paper optimizes the cost of deployment of universal data aggregation points (UDAP) for advanced smart metering infrastructure (AMI), considering coverage and capacity. We propose a routing model between UDAPs, based on minimum spanning tree algorithm (MST) to find the minimum number of links in a specific geo-referenced area. Because it is geo-referenced, the location of the UDAP and the topology of the net are real. The search for optimal locations of a set of candidate sites warns the necessity of an optimization algorithm to minimize candidate sites and turn them into active feasible sites in the previous design to the network deployment. Results imply a strong base point for electricity distribution companies to establish the right number of concentrators (UDAP). There are certain applied AMI communication technologies considered, such as: cellular networks (CDMA, GPRS, and LTE) or the IEEE 802.15.4 g standard. The lowest cost based on the optimal resources usage in infrastructure deployment is very important for planning and scalability phases of AMI network. [ABSTRACT FROM AUTHOR]

Copyright of Desarrollo y Sociedad is the property of Universidad de los Andes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingenium is the property of Facultad de Ciencias Basicas e Ingenieria de Universidad de San Buenaventura, Revista Ingenium and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposes the identification parameter for a human migration model among five Colombian regions. For the identification of parameters an optimization approach is employed where we propose two objective functions. The results obtained with the objective functions are statistically analyzed. The methodology for data analysis employs parametric or non-parametric tests depending on the fulfillment of the assumptions of normality and homoscedasticity (equal variance). To adjust the model, two approaches to the objective function are used. The first considers the total number of population and the second uses the number of inhabitants in each region. By carrying out statistical analyzes, a better adjustment model is observed when considering the number of inhabitants in each region. [ABSTRACT FROM AUTHOR]

This paper presents a literature survey of the current state of the art in vehicle relocation problems applied to EMS. Specially, we focus on describing a classification of this kind of problems, main components that should be taken into account for modeling them, key methods used for solving these problems, objectives pursued by the researchers, key performance measures considered in the EMS literature, software used in the development of models, data collection and verification and validation of the models. We also present some of the relocation policies that have been most frequently evaluated and implemented. [ABSTRACT FROM AUTHOR]

Copyright of Revista Avances: Investigación en Ingeniería is the property of Universidad Libre, Facultad de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Investigaciones Agroindustriales is the property of Revista Colombiana de Investigaciones Agroindustriales del Centro Agropecuario Sena Buga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a simultaneous use of simulation and optimization techniques for the logistic operation planning is presented, specifically aimed to support the decision making processes related with fleet size determination in the supply--distribution process. The study is developed for a Cuban company dedicated to the transportation of goods and warehousing services. The implementation of the proposed tools enabled suggesting the optimal number of trucks to be used, considering minimization of the idle time of trucks and maximization of the customer service level. Experimental results show a significant improvement regarding the lead time reduction and the increment of order fulfillment for the customers of the company. [ABSTRACT FROM AUTHOR]

The challenge of using renewable energy sources means that the production of biofuels and the design of their supply chains, should be pursue environmental and social benefits beyond the purely economic benefit. In this paper are revised some discussions about the impact of biofuels on sustainability and researching in the biofuel supply chains design of first and second generation via mathematical optimization, to analyze how environmental and social concerns have been considered in this problem. Finally, techniques most used optimization were identified and the review found that the concept of sustainability in the design of biofuel supply chains through modeling, is just beginning. [ABSTRACT FROM AUTHOR]

Shell and tube heat exchangers are ones the most important equipment in the industry. Their thermodynamic design is based on the global heat transference coefficient and the pressure drop. In 2007 was settled a new thermodynamic property denominated "Entransy", which expresses the capacity of a body to transfer heat. The loss of this capacity is denominated "Entransy Dissipation". For evaluating the ecological impact of thermal machines, Angulo-Brown created in 1991 the "ecological function". In this paper the"entransy dissipation" and the ecological function were combined and a new expression for evaluating the ecological impact of shell and tube heat exchangers was created. A multi-objective optimization of this equipment wasalso realized. The ecological function and the cost wereused as objective functions. For carry out the optimization the method of the Genetic Algorithms was used. [ABSTRACT FROM AUTHOR]

Copyright of Tecnura is the property of Tecnura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingenius, Revista Ciencia y Tecnología is the property of Universidad Politecnica Salesiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Direito GV is the property of Fundacao Getulio Vargas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios Gerenciales is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dyna is the property of Universidad Nacional de Colombia, Medellin, Facultad de Minas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)