Priorities of the Nurse Schedule by using MODM Approach: A case Study

El efecto bienestar de una migración internacional es habitualmente calculado como la variación del ingreso per capita de quienes quedan atrás luego de la migración. En este trabajo se presenta una crítica de dicho criterio que toma en cuenta que el efecto bienestar es opuesto para asalariados y capitalistas en el caso en que la migración modifique la relación K/L de la economía. Se propone un criterio alternativo que descubra de manera adecuada los efectos que la migración tiene para cada uno de los grupos mencionados.The welfare effect of an international migration is usually calculated as the per capita income variation of those left behind after the migration. A critique of this criterion and a proposal of an alternative one is presented in this paper, considering the fact that in the case in which the overall K/L ratio changes, the welfare effect of wage earners is the opposite of the welfare effect of capital owners.Instituto de Investigaciones Económica

A single-machine scheduling problem with multiple unavailability constraints: A mathematical model and an enhanced variable neighborhood search approach

AbstractThis research focuses on a scheduling problem with multiple unavailability periods and distinct due dates. The objective is to minimize the sum of maximum earliness and tardiness of jobs. In order to optimize the problem exactly a mathematical model is proposed. However due to computational difficulties for large instances of the considered problem a modified variable neighborhood search (VNS) is developed. In basic VNS, the searching process to achieve to global optimum or near global optimum solution is totally random, and it is known as one of the weaknesses of this algorithm. To tackle this weakness, a VNS algorithm is combined with a knowledge module. In the proposed VNS, knowledge module extracts the knowledge of good solution and save them in memory and feed it back to the algorithm during the search process. Computational results show that the proposed algorithm is efficient and effective

A Memetic Algorithm for Hybrid Flowshops with Flexible Machine Availability Constraints

This paper considers the problem of scheduling hybrid flowshops with machine availability constraints (MAC) to minimize makespan. The paper deals with a specific case of MAC caused by preventive maintenance (PM) operations. Contrary to previous papers considering fixed or/and conservative policies, we explore a case in which PM activities might be postponed or expedited while necessary. Regarding this flexibility in PM activities, we expect to obtain more efficient schedule. A simple technique is employed to schedule production jobs along with the flexible MACs caused by PM. To solve the problem, we present a high performing metaheuristic based on memetic algorithm incorporating some advanced features. To evaluate the proposed algorithm, the paper compares the proposed algorithm with several wellknown algorithms taken from the literature. Finally, we conclude that the proposed algorithm outperforms other algorithms

A new IPSO-SA approach for cardinality constrained portfolio optimization

The problem of portfolio optimization has always been a key concern for investors. This paper addresses a realistic portfolio optimization problem with floor, ceiling, and cardinality constraints. This problem is a mixed integer quadratic programming where traditional optimization methods fail to find the optimal solution, efficiently. The present paper develops a new hybrid approach based on an improved particle swarm optimization (PSO) and a modified simulated annealing (SA) methods to find the cardinality constrained efficient frontier. The proposed algorithm benefits simple and easy characteristics of PSO with an adaptation of inertia weights and constriction factor. In addition, incorporating an SA procedure into IPSO helps escaping from local optima and improves the precision of convergence. Computational results on benchmark problems with up to 225 assets signify that our proposed algorithm exceeds not only the standard PSO but also the other heuristic algorithms previously presented to solve the cardinality constrained portfolio problem

A Hierarchical Production Planning and Finite Scheduling Framework for Part Families in Flexible Job-shop (with a case study)

Tendency to optimization in last decades has resulted in creating multi-product manufacturing systems. Production planning in such systems is difficult, because optimal production volume that is calculated must be consistent with limitation of production system. Hence, integration has been proposed to decide about these problems concurrently. Main problem in integration is how we can relate production planning in medium-term timeframe with scheduling in short-term timeframe. Our contribution creates production planning and scheduling framework in flexible job shop environment with respect to time-limit of each machine in order to produce different parts families in automotive industry. Production planning and scheduling have iterative relationship. In this strategy information flow is transformed reciprocative between production planning and scheduling for satisfying time-limit of each machine. The proposed production planning has heuristic approach and renders a procedure to determine production priority of different part families based on safety stock. Scheduling is performed with ant colony optimization and assigns machine in order of priority to different part families on each frozen horizon. Results showed that, the proposed heuristic algorithm for planning decreased parts inventory at the end of planning horizon. Also, results of proposed ant colony optimization was near the optimal solution .The framework was performed to produce sixty four different part families in flexible job-shop with fourteen different machines. Output from this approach determined volume of production batches for part families on each frozen horizon and assigned different operations to machines

Location-Allocation and Scheduling of Inbound and Outbound Trucks in Multiple Cross-Dockings Considering Breakdown Trucks

This paper studies multiple cross-dockings where the loads are transferred from origins (suppliers) to destinations (customers) through cross-docking facilities. Products are no longer stored in intermediate depots and incoming shipments are consolidated based on customer demands and immediately delivered to them to their destinations. In this paper, each cross-docking has a covering radius that customers can be served by at least one cross-docking provided. In addition, this paper considers the breakdown of trucks. We present a two-stage model for the location of cross-docking centers and scheduling inbound and outbound trucks in multiple cross-dockings.We work on minimizing the transportation cost in a network by loading trucks in the supplier locations and route them to the customers via cross-docking facilities. The objective, in the first stage, is to minimize transportation cost of delivering products from suppliers to open cross-docks and cross-docks to the customers; in the second-stage, the objective is to minimize the makespans of open cross-dockings and the total weighted summation of completion time. Due to the difficulty of obtaining the optimum solution tomedium- and large-scale problems, we ‌propose four types of metaheuristic algorithms, i.e., genetic, simulated annealing, differential evolution, and hybrid algorithms.The result showed that simulated annealing is the best algorithm between the four algorithms

A Model for Project Scheduling with Fuzzy Precedence Links

Abstract In the real world for many projects we have to use human judgment for estimating the duration of activities. A way to deal with this imprecise data is to employ the concept of fuzziness, where the vague activity times can be represented by fuzzy sets. This paper presents a new method based on fuzzy theory for solving fuzzy project scheduling in fuzzy environment. The duration of activities is triangular fuzzy numbers (TFN). Also for the first time in the literature, we consider the relationship between activities is not crisp and assume it is a triangular fuzzy number. The proposed solution method is based on linear programming (LP) model that gives us several parameters of project such as earliest time, latest time, and slack times in term of TFN

MATH APPS UTILIZATION: ITS PERCEIVED EFFECTS TO THE ACADEMIC PERFORMANCE OF MATHEMATICS MAJOR STUDENTS

This study aimed to determine the perceived effects of apps utilization to study habits and academic performance. Further, it also sought to determine the views of the participants and respondents on their engagement in math apps and their relationship with study habits and academic performance. This study made use of explanatory-sequential design. The purposive sampling design was used to determine the respondents in quantitative data while the quota sampling design was also used to determine the participants in qualitative data. The study revealed that the mathematical application that is mostly used by the students is the calculator app as it garnered the highest percentage value of 80.85.%. The participants agreed that math applications serve as an aid for math problems, aid for lack of teaching by the teacher, promote learning of specific lessons and increase, and help in improving their academic performance. Respondents’ perception of their utilization of math apps is due to technical problems. The respondents also agreed that math application also affected their study habits in which they become dependent on it which led to laziness and tiredness. In addition, this study also found that there is a significant relationship between respondents’ utilization of math applications and their study habits. Lastly, there is also a significant relationship between the study habits and academic performance of selected math students of Notre Dame of Midsayap College.  Article visualizations

ONLINE MULTIMEDIA SCREEN TIME AND LEVEL OF HAPPINESS OF THE COLLEGE STUDENTS

Online multimedia is very popular in today’s generation. Many people are using different online multimedia platforms as a means to enjoy, study, and connect with other people around the world. This study sought to determine the online multimedia screen time and the level of happiness of the college students of Notre Dame of Midsayap College as well as the relationship between these two variables. The researchers used descriptive- correlational research design and purposive sampling technique in gathering data through a survey questionnaire administered to 50 respondents who are active users of different online multimedia. The findings of the study revealed that online multimedia screen time and level of happiness have a significant relationship. Furthermore, contrary to the findings of previous studies, this study suggests that if online multimedia screen time is increased, students’ level of happiness also increases.  Article visualizations