Flexible Job Shop Scheduling Problem Using an Improved Ant Colony Optimization

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Lei Wang

2017-01-01

Full Text Available As an extension of the classical job shop scheduling problem, the flexible job shop scheduling problem (FJSP plays an important role in real production systems. In FJSP, an operation is allowed to be processed on more than one alternative machine. It has been proven to be a strongly NP-hard problem. Ant colony optimization (ACO has been proven to be an efficient approach for dealing with FJSP. However, the basic ACO has two main disadvantages including low computational efficiency and local optimum. In order to overcome these two disadvantages, an improved ant colony optimization (IACO is proposed to optimize the makespan for FJSP. The following aspects are done on our improved ant colony optimization algorithm: select machine rule problems, initialize uniform distributed mechanism for ants, change pheromone’s guiding mechanism, select node method, and update pheromone’s mechanism. An actual production instance and two sets of well-known benchmark instances are tested and comparisons with some other approaches verify the effectiveness of the proposed IACO. The results reveal that our proposed IACO can provide better solution in a reasonable computational time.

An improved sheep flock heredity algorithm for job shop scheduling and flow shop scheduling problems

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Chandramouli Anandaraman

2011-10-01

Full Text Available Job Shop Scheduling Problem (JSSP and Flow Shop Scheduling Problem (FSSP are strong NP-complete combinatorial optimization problems among class of typical production scheduling problems. An improved Sheep Flock Heredity Algorithm (ISFHA is proposed in this paper to find a schedule of operations that can minimize makespan. In ISFHA, the pairwise mutation operation is replaced by a single point mutation process with a probabilistic property which guarantees the feasibility of the solutions in the local search domain. A Robust-Replace (R-R heuristic is introduced in place of chromosomal crossover to enhance the global search and to improve the convergence. The R-R heuristic is found to enhance the exploring potential of the algorithm and enrich the diversity of neighborhoods. Experimental results reveal the effectiveness of the proposed algorithm, whose optimization performance is markedly superior to that of genetic algorithms and is comparable to the best results reported in the literature.

A modified genetic algorithm with fuzzy roulette wheel selection for job-shop scheduling problems

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Thammano, Arit; Teekeng, Wannaporn

2015-05-01

The job-shop scheduling problem is one of the most difficult production planning problems. Since it is in the NP-hard class, a recent trend in solving the job-shop scheduling problem is shifting towards the use of heuristic and metaheuristic algorithms. This paper proposes a novel metaheuristic algorithm, which is a modification of the genetic algorithm. This proposed algorithm introduces two new concepts to the standard genetic algorithm: (1) fuzzy roulette wheel selection and (2) the mutation operation with tabu list. The proposed algorithm has been evaluated and compared with several state-of-the-art algorithms in the literature. The experimental results on 53 JSSPs show that the proposed algorithm is very effective in solving the combinatorial optimization problems. It outperforms all state-of-the-art algorithms on all benchmark problems in terms of the ability to achieve the optimal solution and the computational time.

Solving the flexible job shop problem by hybrid metaheuristics-based multiagent model

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Nouri, Houssem Eddine; Belkahla Driss, Olfa; Ghédira, Khaled

2018-03-01

The flexible job shop scheduling problem (FJSP) is a generalization of the classical job shop scheduling problem that allows to process operations on one machine out of a set of alternative machines. The FJSP is an NP-hard problem consisting of two sub-problems, which are the assignment and the scheduling problems. In this paper, we propose how to solve the FJSP by hybrid metaheuristics-based clustered holonic multiagent model. First, a neighborhood-based genetic algorithm (NGA) is applied by a scheduler agent for a global exploration of the search space. Second, a local search technique is used by a set of cluster agents to guide the research in promising regions of the search space and to improve the quality of the NGA final population. The efficiency of our approach is explained by the flexible selection of the promising parts of the search space by the clustering operator after the genetic algorithm process, and by applying the intensification technique of the tabu search allowing to restart the search from a set of elite solutions to attain new dominant scheduling solutions. Computational results are presented using four sets of well-known benchmark literature instances. New upper bounds are found, showing the effectiveness of the presented approach.

A decomposition heuristics based on multi-bottleneck machines for large-scale job shop scheduling problems

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Yingni Zhai

2014-10-01

Full Text Available Purpose: A decomposition heuristics based on multi-bottleneck machines for large-scale job shop scheduling problems (JSP is proposed.Design/methodology/approach: In the algorithm, a number of sub-problems are constructed by iteratively decomposing the large-scale JSP according to the process route of each job. And then the solution of the large-scale JSP can be obtained by iteratively solving the sub-problems. In order to improve the sub-problems' solving efficiency and the solution quality, a detection method for multi-bottleneck machines based on critical path is proposed. Therewith the unscheduled operations can be decomposed into bottleneck operations and non-bottleneck operations. According to the principle of “Bottleneck leads the performance of the whole manufacturing system” in TOC (Theory Of Constraints, the bottleneck operations are scheduled by genetic algorithm for high solution quality, and the non-bottleneck operations are scheduled by dispatching rules for the improvement of the solving efficiency.Findings: In the process of the sub-problems' construction, partial operations in the previous scheduled sub-problem are divided into the successive sub-problem for re-optimization. This strategy can improve the solution quality of the algorithm. In the process of solving the sub-problems, the strategy that evaluating the chromosome's fitness by predicting the global scheduling objective value can improve the solution quality.Research limitations/implications: In this research, there are some assumptions which reduce the complexity of the large-scale scheduling problem. They are as follows: The processing route of each job is predetermined, and the processing time of each operation is fixed. There is no machine breakdown, and no preemption of the operations is allowed. The assumptions should be considered if the algorithm is used in the actual job shop.Originality/value: The research provides an efficient scheduling method for the

A New Method Based on Simulation-Optimization Approach to Find Optimal Solution in Dynamic Job-shop Scheduling Problem with Breakdown and Rework

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Farzad Amirkhani

2017-03-01

The proposed method is implemented on classical job-shop problems with objective of makespan and results are compared with mixed integer programming model. Moreover, the appropriate dispatching priorities are achieved for dynamic job-shop problem minimizing a multi-objective criteria. The results show that simulation-based optimization are highly capable to capture the main characteristics of the shop and produce optimal/near-optimal solutions with highly credibility degree.

Job shop scheduling by simulated annealing

NARCIS (Netherlands)

Laarhoven, van P.J.M.; Aarts, E.H.L.; Lenstra, J.K.

1992-01-01

We describe an approximation algorithm for the problem of finding the minimum makespan in a job shop. The algorithm is based on simulated annealing, a generalization of the well known iterative improvement approach to combinatorial optimization problems. The generalization involves the acceptance of

A fine-grained parallel algorithm for the cyclic flexible job shop problem

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Bożejko Wojciech

2017-06-01

Full Text Available In this paper there is considered a flexible job shop problem of operations scheduling. The new, very fast method of determination of cycle time is presented. In the design of heuristic algorithm there was the neighborhood inspired by the game of golf applied. Lower bound of the criterion function was used in the search of the neighborhood.

A Pareto archive floating search procedure for solving multi-objective flexible job shop scheduling problem

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J. S. Sadaghiani

2014-04-01

Full Text Available Flexible job shop scheduling problem is a key factor of using efficiently in production systems. This paper attempts to simultaneously optimize three objectives including minimization of the make span, total workload and maximum workload of jobs. Since the multi objective flexible job shop scheduling problem is strongly NP-Hard, an integrated heuristic approach has been used to solve it. The proposed approach was based on a floating search procedure that has used some heuristic algorithms. Within floating search procedure utilize local heuristic algorithms; it makes the considered problem into two sections including assigning and sequencing sub problem. First of all search is done upon assignment space achieving an acceptable solution and then search would continue on sequencing space based on a heuristic algorithm. This paper has used a multi-objective approach for producing Pareto solution. Thus proposed approach was adapted on NSGA II algorithm and evaluated Pareto-archives. The elements and parameters of the proposed algorithms were adjusted upon preliminary experiments. Finally, computational results were used to analyze efficiency of the proposed algorithm and this results showed that the proposed algorithm capable to produce efficient solutions.

Solving multi-objective job shop problem using nature-based algorithms: new Pareto approximation features

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Jarosław Rudy

2015-01-01

Full Text Available In this paper the job shop scheduling problem (JSP with minimizing two criteria simultaneously is considered. JSP is frequently used model in real world applications of combinatorial optimization. Multi-objective job shop problems (MOJSP were rarely studied. We implement and compare two multi-agent nature-based methods, namely ant colony optimization (ACO and genetic algorithm (GA for MOJSP. Both of those methods employ certain technique, taken from the multi-criteria decision analysis in order to establish ranking of solutions. ACO and GA differ in a method of keeping information about previously found solutions and their quality, which affects the course of the search. In result, new features of Pareto approximations provided by said algorithms are observed: aside from the slight superiority of the ACO method the Pareto frontier approximations provided by both methods are disjoint sets. Thus, both methods can be used to search mutually exclusive areas of the Pareto frontier.

Multiobjective Joint Optimization of Production Scheduling and Maintenance Planning in the Flexible Job-Shop Problem

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Jianfei Ye

2015-01-01

Full Text Available In order to solve the joint optimization of production scheduling and maintenance planning problem in the flexible job-shop, a multiobjective joint optimization model considering the maximum completion time and maintenance costs per unit time is established based on the concept of flexible job-shop and preventive maintenance. A weighted sum method is adopted to eliminate the index dimension. In addition, a double-coded genetic algorithm is designed according to the problem characteristics. The best result under the circumstances of joint decision-making is obtained through multiple simulation experiments, which proves the validity of the algorithm. We can prove the superiority of joint optimization model by comparing the result of joint decision-making project with the result of independent decision-making project under fixed preventive maintenance period. This study will enrich and expand the theoretical framework and analytical methods of this problem; it provides a scientific decision analysis method for enterprise to make production plan and maintenance plan.

The finite horizon economic lot sizing problem in job shops : the multiple cycle approach

NARCIS (Netherlands)

Ouenniche, J.; Bertrand, J.W.M.

2001-01-01

This paper addresses the multi-product, finite horizon, static demand, sequencing, lot sizing and scheduling problem in a job shop environment where the planning horizon length is finite and fixed by management. The objective pursued is to minimize the sum of setup costs, and work-in-process and

Heuristic and Exact Algorithms for the Two-Machine Just in Time Job Shop Scheduling Problem

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Mohammed Al-Salem

2016-01-01

Full Text Available The problem addressed in this paper is the two-machine job shop scheduling problem when the objective is to minimize the total earliness and tardiness from a common due date (CDD for a set of jobs when their weights equal 1 (unweighted problem. This objective became very significant after the introduction of the Just in Time manufacturing approach. A procedure to determine whether the CDD is restricted or unrestricted is developed and a semirestricted CDD is defined. Algorithms are introduced to find the optimal solution when the CDD is unrestricted and semirestricted. When the CDD is restricted, which is a much harder problem, a heuristic algorithm is proposed to find approximate solutions. Through computational experiments, the heuristic algorithms’ performance is evaluated with problems up to 500 jobs.

Cultural-Based Genetic Tabu Algorithm for Multiobjective Job Shop Scheduling

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Yuzhen Yang

2014-01-01

Full Text Available The job shop scheduling problem, which has been dealt with by various traditional optimization methods over the decades, has proved to be an NP-hard problem and difficult in solving, especially in the multiobjective field. In this paper, we have proposed a novel quadspace cultural genetic tabu algorithm (QSCGTA to solve such problem. This algorithm provides a different structure from the original cultural algorithm in containing double brief spaces and population spaces. These spaces deal with different levels of populations globally and locally by applying genetic and tabu searches separately and exchange information regularly to make the process more effective towards promising areas, along with modified multiobjective domination and transform functions. Moreover, we have presented a bidirectional shifting for the decoding process of job shop scheduling. The computational results we presented significantly prove the effectiveness and efficiency of the cultural-based genetic tabu algorithm for the multiobjective job shop scheduling problem.

Extended precedence preservative crossover for job shop scheduling problems

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Ong, Chung Sin; Moin, Noor Hasnah; Omar, Mohd

2013-04-01

Job shop scheduling problems (JSSP) is one of difficult combinatorial scheduling problems. A wide range of genetic algorithms based on the two parents crossover have been applied to solve the problem but multi parents (more than two parents) crossover in solving the JSSP is still lacking. This paper proposes the extended precedence preservative crossover (EPPX) which uses multi parents for recombination in the genetic algorithms. EPPX is a variation of the precedence preservative crossover (PPX) which is one of the crossovers that perform well to find the solutions for the JSSP. EPPX is based on a vector to determine the gene selected in recombination for the next generation. Legalization of children (offspring) can be eliminated due to the JSSP representation encoded by using permutation with repetition that guarantees the feasibility of chromosomes. The simulations are performed on a set of benchmarks from the literatures and the results are compared to ensure the sustainability of multi parents recombination in solving the JSSP.

Proposta de classificação hierarquizada dos modelos de solução para o problema de job shop scheduling A proposition of hierarchical classification for solution models in the job shop scheduling problem

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Ricardo Ferrari Pacheco

1999-04-01

Full Text Available Este artigo propõe uma classificação hierarquizada dos modelos utilizados na solução do problema de programação da produção intermitente do tipo job shop, incluindo tanto os que fornecem solução ótima, quanto os modelos heurísticos mais recentes baseados em métodos de busca estendida. Por meio dessa classificação obteve-se um painel amplo dos modelos existentes, evidenciando as diferentes abordagens do problema e suas soluções, com o objetivo de proporcionar uma orientação preliminar na escolha do modelo de job shop scheduling mais adequado.This paper proposes a hierarchical model classification used in the job shop scheduling problem, including those that provide an optimal solution and the more recent ones based on heuristics, called extended search methods. A panel with the existing models is obtained by this classification, and solutions and approach differences are highlighted with the aim of a preliminary orientation on the choice of a more adequate job shop scheduling model.

Multiagent scheduling method with earliness and tardiness objectives in flexible job shops.

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Wu, Zuobao; Weng, Michael X

2005-04-01

Flexible job-shop scheduling problems are an important extension of the classical job-shop scheduling problems and present additional complexity. Such problems are mainly due to the existence of a considerable amount of overlapping capacities with modern machines. Classical scheduling methods are generally incapable of addressing such capacity overlapping. We propose a multiagent scheduling method with job earliness and tardiness objectives in a flexible job-shop environment. The earliness and tardiness objectives are consistent with the just-in-time production philosophy which has attracted significant attention in both industry and academic community. A new job-routing and sequencing mechanism is proposed. In this mechanism, two kinds of jobs are defined to distinguish jobs with one operation left from jobs with more than one operation left. Different criteria are proposed to route these two kinds of jobs. Job sequencing enables to hold a job that may be completed too early. Two heuristic algorithms for job sequencing are developed to deal with these two kinds of jobs. The computational experiments show that the proposed multiagent scheduling method significantly outperforms the existing scheduling methods in the literature. In addition, the proposed method is quite fast. In fact, the simulation time to find a complete schedule with over 2000 jobs on ten machines is less than 1.5 min.

Job shop scheduling by local search

NARCIS (Netherlands)

Vaessens, R.J.M.; Aarts, E.H.L.; Lenstra, J.K.

1994-01-01

We survey solution methods for the job shop scheduling problem with an emphasis on local search. We discuss both cleterministic and randomized local search methods as well as the applied neighborhoods. We compare the computational performance of the various methods in terms of their effectiveness

Forecasting of indirect consumables for a Job Shop

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Shakeel, M.; Khan, S.; Khan, W. A.

2016-08-01

A job shop has an arrangement where similar machines (Direct consumables) are grouped together and use indirect consumables to produce a product. The indirect consumables include hack saw blades, emery paper, painting brush etc. The job shop is serving various orders at a particular time for the optimal operation of job shop. Forecasting is required to predict the demand of direct and indirect consumables in a job shop. Forecasting is also needed to manage lead time, optimize inventory cost and stock outs. The objective of this research is to obtain the forecast for indirect consumables. The paper shows how job shop can manage their indirect consumables more accurately by establishing a new technique of forecasting. This results in profitable use of job shop by multiple users.

An Improved Version of Discrete Particle Swarm Optimization for Flexible Job Shop Scheduling Problem with Fuzzy Processing Time

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Song Huang

2016-01-01

Full Text Available The fuzzy processing time occasionally exists in job shop scheduling problem of flexible manufacturing system. To deal with fuzzy processing time, fuzzy flexible job shop model was established in several papers and has attracted numerous researchers’ attention recently. In our research, an improved version of discrete particle swarm optimization (IDPSO is designed to solve flexible job shop scheduling problem with fuzzy processing time (FJSPF. In IDPSO, heuristic initial methods based on triangular fuzzy number are developed, and a combination of six initial methods is applied to initialize machine assignment and random method is used to initialize operation sequence. Then, some simple and effective discrete operators are employed to update particle’s position and generate new particles. In order to guide the particles effectively, we extend global best position to a set with several global best positions. Finally, experiments are designed to investigate the impact of four parameters in IDPSO by Taguchi method, and IDPSO is tested on five instances and compared with some state-of-the-art algorithms. The experimental results show that the proposed algorithm can obtain better solutions for FJSPF and is more competitive than the compared algorithms.

Heuristics for no-wait flow shop scheduling problem

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Kewal Krishan Nailwal

2016-09-01

Full Text Available No-wait flow shop scheduling refers to continuous flow of jobs through different machines. The job once started should have the continuous processing through the machines without wait. This situation occurs when there is a lack of an intermediate storage between the processing of jobs on two consecutive machines. The problem of no-wait with the objective of minimizing makespan in flow shop scheduling is NP-hard; therefore the heuristic algorithms are the key to solve the problem with optimal solution or to approach nearer to optimal solution in simple manner. The paper describes two heuristics, one constructive and an improvement heuristic algorithm obtained by modifying the constructive one for sequencing n-jobs through m-machines in a flow shop under no-wait constraint with the objective of minimizing makespan. The efficiency of the proposed heuristic algorithms is tested on 120 Taillard’s benchmark problems found in the literature against the NEH under no-wait and the MNEH heuristic for no-wait flow shop problem. The improvement heuristic outperforms all heuristics on the Taillard’s instances by improving the results of NEH by 27.85%, MNEH by 22.56% and that of the proposed constructive heuristic algorithm by 24.68%. To explain the computational process of the proposed algorithm, numerical illustrations are also given in the paper. Statistical tests of significance are done in order to draw the conclusions.

Iterated greedy algorithms to minimize the total family flow time for job-shop scheduling with job families and sequence-dependent set-ups

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Kim, Ji-Su; Park, Jung-Hyeon; Lee, Dong-Ho

2017-10-01

This study addresses a variant of job-shop scheduling in which jobs are grouped into job families, but they are processed individually. The problem can be found in various industrial systems, especially in reprocessing shops of remanufacturing systems. If the reprocessing shop is a job-shop type and has the component-matching requirements, it can be regarded as a job shop with job families since the components of a product constitute a job family. In particular, sequence-dependent set-ups in which set-up time depends on the job just completed and the next job to be processed are also considered. The objective is to minimize the total family flow time, i.e. the maximum among the completion times of the jobs within a job family. A mixed-integer programming model is developed and two iterated greedy algorithms with different local search methods are proposed. Computational experiments were conducted on modified benchmark instances and the results are reported.

Neighbourhood generation mechanism applied in simulated annealing to job shop scheduling problems

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Cruz-Chávez, Marco Antonio

2015-11-01

This paper presents a neighbourhood generation mechanism for the job shop scheduling problems (JSSPs). In order to obtain a feasible neighbour with the generation mechanism, it is only necessary to generate a permutation of an adjacent pair of operations in a scheduling of the JSSP. If there is no slack time between the adjacent pair of operations that is permuted, then it is proven, through theory and experimentation, that the new neighbour (schedule) generated is feasible. It is demonstrated that the neighbourhood generation mechanism is very efficient and effective in a simulated annealing.

An Explanatory Study of Lean Practices in Job Shop Production/ Special Job Production/ Discrete Production/ Batch Shop Production Industries

OpenAIRE

Lavlesh Kumar Sharma; Ravindra Mohan Saxena

2014-01-01

In this paper, the study explores the benefits and advantages of Lean Practices or Lean Thinking in Job shop production/ Special job production/ Discrete production/ Batch shop production industries. The Lean Practices have been applied more compatible in Job shop production than in the continuous/ mass production because of several barriers and hurdles in the industrial context that influence the whole processes again and again, this happens due to the lack of knowledge about...

Genetic algorithm and neural network hybrid approach for job-shop scheduling

OpenAIRE

Zhao, Kai; Yang, Shengxiang; Wang, Dingwei

1998-01-01

Copyright @ 1998 ACTA Press This paper proposes a genetic algorithm (GA) and constraint satisfaction adaptive neural network (CSANN) hybrid approach for job-shop scheduling problems. In the hybrid approach, GA is used to iterate for searching optimal solutions, CSANN is used to obtain feasible solutions during the iteration of genetic algorithm. Simulations have shown the valid performance of the proposed hybrid approach for job-shop scheduling with respect to the quality of solutions and ...

No-Wait Job Shop Scheduling, a Constraint Propagation Approach

NARCIS (Netherlands)

Lennartz, P.M.

2006-01-01

Multi-machine scheduling problems have earned themselves a reputation of intractability. In this thesis we try to solve a special kind of these problems, the so-called no-wait job shop problems. In an instance of this problem-class we are given a number of operations that are to be executed on a

A Hybrid Genetic Algorithm with a Knowledge-Based Operator for Solving the Job Shop Scheduling Problems

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Hamed Piroozfard

2016-01-01

Full Text Available Scheduling is considered as an important topic in production management and combinatorial optimization in which it ubiquitously exists in most of the real-world applications. The attempts of finding optimal or near optimal solutions for the job shop scheduling problems are deemed important, because they are characterized as highly complex and NP-hard problems. This paper describes the development of a hybrid genetic algorithm for solving the nonpreemptive job shop scheduling problems with the objective of minimizing makespan. In order to solve the presented problem more effectively, an operation-based representation was used to enable the construction of feasible schedules. In addition, a new knowledge-based operator was designed based on the problem’s characteristics in order to use machines’ idle times to improve the solution quality, and it was developed in the context of function evaluation. A machine based precedence preserving order-based crossover was proposed to generate the offspring. Furthermore, a simulated annealing based neighborhood search technique was used to improve the local exploitation ability of the algorithm and to increase its population diversity. In order to prove the efficiency and effectiveness of the proposed algorithm, numerous benchmarked instances were collected from the Operations Research Library. Computational results of the proposed hybrid genetic algorithm demonstrate its effectiveness.

Evaluating the mathematical models to Solve Job Shop Problem with the Use of human resources specialists in projects

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Renato Penha

2012-10-01

Full Text Available A project can be defined as a complex system. This requires the use of resources (human, material, technology, etc., allocated among alternative uses, as a means to achieve specific goals by the presence of constraints of different orders. The planning, allocation and prioritization of resources, including human resource specialists (HRE, is performed by means of single project management.This treatment can cause internal strife by using the same resource or even its underuse, and may worsen in software development environments due to the high degree of interdependence, uncertainty and risk of each project. This need is related to the so called Job Shop Problem (JSP. In this context, the objective of this study is to evaluate the mathematical models of genetic algorithm and optimization and their contributions to solve Job Shop Problem in software development projects with the use of human resources specialists.

A Hybrid Multiobjective Evolutionary Approach for Flexible Job-Shop Scheduling Problems

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Jian Xiong

2012-01-01

Full Text Available This paper addresses multiobjective flexible job-shop scheduling problem (FJSP with three simultaneously considered objectives: minimizing makespan, minimizing total workload, and minimizing maximal workload. A hybrid multiobjective evolutionary approach (H-MOEA is developed to solve the problem. According to the characteristic of FJSP, a modified crowding distance measure is introduced to maintain the diversity of individuals. In the proposed H-MOEA, well-designed chromosome representation and genetic operators are developed for FJSP. Moreover, a local search procedure based on critical path theory is incorporated in H-MOEA to improve the convergence ability of the algorithm. Experiment results on several well-known benchmark instances demonstrate the efficiency and stability of the proposed algorithm. The comparison with other recently published approaches validates that H-MOEA can obtain Pareto-optimal solutions with better quality and/or diversity.

A RELATIONAL DATABASE APPROACH TO THE JOB SHOP SCHEDULING PROBLEM

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P. Lindeque

2012-01-01

Full Text Available

ENGLISH ABSTRACT: This paper will attempt to illuminate the advantages of an approach to the job shop scheduling problem using priority based search algorithms and database technology. It will use as basis a system developed for and implemented at a large manufacturing plant. The paper will also attempt to make some predictions as to future developments in these techniques and look at the possibility of including new technologies such as expert systems.

AFRIKAANSE OPSOMMING: Die voordele en toepaslikheid van prioriteits-gebaseerde soek-algoritmes en databasisstelsels op die taakwerkswinkelprobleem sal in hierdie artikel uitgelig word. 'n Stelsel wat by 'n groot vervaardigingsonderneming geimplementeer is, sal as uitgangspunt gebruik word. Toekomstige ontwikkelings in bogenoemde tegnieke en die moontlike insluiting van ekspertstelsels sal ook ondersoek word.

Multi-objective flexible job shop scheduling problem using variable neighborhood evolutionary algorithm

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Wang, Chun; Ji, Zhicheng; Wang, Yan

2017-07-01

In this paper, multi-objective flexible job shop scheduling problem (MOFJSP) was studied with the objects to minimize makespan, total workload and critical workload. A variable neighborhood evolutionary algorithm (VNEA) was proposed to obtain a set of Pareto optimal solutions. First, two novel crowded operators in terms of the decision space and object space were proposed, and they were respectively used in mating selection and environmental selection. Then, two well-designed neighborhood structures were used in local search, which consider the problem characteristics and can hold fast convergence. Finally, extensive comparison was carried out with the state-of-the-art methods specially presented for solving MOFJSP on well-known benchmark instances. The results show that the proposed VNEA is more effective than other algorithms in solving MOFJSP.

Application of Tabu Search Algorithm in Job Shop Scheduling

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Betrianis Betrianis

2010-10-01

Full Text Available Tabu Search is one of local search methods which is used to solve the combinatorial optimization problem. This method aimed is to make the searching process of the best solution in a complex combinatorial optimization problem(np hard, ex : job shop scheduling problem, became more effective, in a less computational time but with no guarantee to optimum solution.In this paper, tabu search is used to solve the job shop scheduling problem consists of 3 (three cases, which is ordering package of September, October and November with objective of minimizing makespan (Cmax. For each ordering package, there is a combination for initial solution and tabu list length. These result then  compared with 4 (four other methods using basic dispatching rules such as Shortest Processing Time (SPT, Earliest Due Date (EDD, Most Work Remaining (MWKR dan First Come First Served (FCFS. Scheduling used Tabu Search Algorithm is sensitive for variables changes and gives makespan shorter than scheduling used by other four methods.

A novel integrated condition-based maintenance and stochastic flexible job shop scheduling problem

DEFF Research Database (Denmark)

Rahmati, Seyed Habib A.; Ahmadi, Abbas; Govindan, Kannan

2018-01-01

the level of the system optimization. By means of this equipment, managers can benefit from a condition-based maintenance (CBM) for monitoring and managing their system. The chief aim of the paper is to develop a stochastic maintenance problem based on CBM activities engaged with a complex applied......Integrated consideration of production planning and maintenance processes is a real world assumption. Specifically, by improving the monitoring equipment such as various sensors or product-embedded information devices in recent years, joint assessment of these processes is inevitable for enhancing...... production problem called flexible job shop scheduling problem (FJSP). This integrated problem considers two maintenance scenarios in terms of corrective maintenance (CM) and preventive maintenance (PM). The activation of scenario is done by monitoring the degradation condition of the system and comparing...

Workload control in job shops, grasping the tap

NARCIS (Netherlands)

Land, Martin Jaap

2004-01-01

The term job shops is used to indicate companies that produce customer-specific components in small batches. Jobs (production orders) in a job shop are characterised by a large variety of routings and operation processing times. This variety, combined with irregular order arrivals, generally leads

A neural network approach to job-shop scheduling.

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Zhou, D N; Cherkassky, V; Baldwin, T R; Olson, D E

1991-01-01

A novel analog computational network is presented for solving NP-complete constraint satisfaction problems, i.e. job-shop scheduling. In contrast to most neural approaches to combinatorial optimization based on quadratic energy cost function, the authors propose to use linear cost functions. As a result, the network complexity (number of neurons and the number of resistive interconnections) grows only linearly with problem size, and large-scale implementations become possible. The proposed approach is related to the linear programming network described by D.W. Tank and J.J. Hopfield (1985), which also uses a linear cost function for a simple optimization problem. It is shown how to map a difficult constraint-satisfaction problem onto a simple neural net in which the number of neural processors equals the number of subjobs (operations) and the number of interconnections grows linearly with the total number of operations. Simulations show that the authors' approach produces better solutions than existing neural approaches to job-shop scheduling, i.e. the traveling salesman problem-type Hopfield approach and integer linear programming approach of J.P.S. Foo and Y. Takefuji (1988), in terms of the quality of the solution and the network complexity.

A Flexible Job Shop Scheduling Problem with Controllable Processing Times to Optimize Total Cost of Delay and Processing

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Hadi Mokhtari

2015-11-01

Full Text Available In this paper, the flexible job shop scheduling problem with machine flexibility and controllable process times is studied. The main idea is that the processing times of operations may be controlled by consumptions of additional resources. The purpose of this paper to find the best trade-off between processing cost and delay cost in order to minimize the total costs. The proposed model, flexible job shop scheduling with controllable processing times (FJCPT, is formulated as an integer non-linear programming (INLP model and then it is converted into an integer linear programming (ILP model. Due to NP-hardness of FJCPT, conventional analytic optimization methods are not efficient. Hence, in order to solve the problem, a Scatter Search (SS, as an efficient metaheuristic method, is developed. To show the effectiveness of the proposed method, numerical experiments are conducted. The efficiency of the proposed algorithm is compared with that of a genetic algorithm (GA available in the literature for solving FJSP problem. The results showed that the proposed SS provide better solutions than the existing GA.

Variable Neighbourhood Search and Mathematical Programming for Just-in-Time Job-Shop Scheduling Problem

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Sunxin Wang

2014-01-01

Full Text Available This paper presents a combination of variable neighbourhood search and mathematical programming to minimize the sum of earliness and tardiness penalty costs of all operations for just-in-time job-shop scheduling problem (JITJSSP. Unlike classical E/T scheduling problem with each job having its earliness or tardiness penalty cost, each operation in this paper has its earliness and tardiness penalties, which are paid if the operation is completed before or after its due date. Our hybrid algorithm combines (i a variable neighbourhood search procedure to explore the huge feasible solution spaces efficiently by alternating the swap and insertion neighbourhood structures and (ii a mathematical programming model to optimize the completion times of the operations for a given solution in each iteration procedure. Additionally, a threshold accepting mechanism is proposed to diversify the local search of variable neighbourhood search. Computational results on the 72 benchmark instances show that our algorithm can obtain the best known solution for 40 problems, and the best known solutions for 33 problems are updated.

Energy-efficient approach to minimizing the energy consumption in an extended job-shop scheduling problem

Science.gov (United States)

Tang, Dunbing; Dai, Min

2015-09-01

The traditional production planning and scheduling problems consider performance indicators like time, cost and quality as optimization objectives in manufacturing processes. However, environmentally-friendly factors like energy consumption of production have not been completely taken into consideration. Against this background, this paper addresses an approach to modify a given schedule generated by a production planning and scheduling system in a job shop floor, where machine tools can work at different cutting speeds. It can adjust the cutting speeds of the operations while keeping the original assignment and processing sequence of operations of each job fixed in order to obtain energy savings. First, the proposed approach, based on a mixed integer programming mathematical model, changes the total idle time of the given schedule to minimize energy consumption in the job shop floor while accepting the optimal solution of the scheduling objective, makespan. Then, a genetic-simulated annealing algorithm is used to explore the optimal solution due to the fact that the problem is strongly NP-hard. Finally, the effectiveness of the approach is performed smalland large-size instances, respectively. The experimental results show that the approach can save 5%-10% of the average energy consumption while accepting the optimal solution of the makespan in small-size instances. In addition, the average maximum energy saving ratio can reach to 13%. And it can save approximately 1%-4% of the average energy consumption and approximately 2.4% of the average maximum energy while accepting the near-optimal solution of the makespan in large-size instances. The proposed research provides an interesting point to explore an energy-aware schedule optimization for a traditional production planning and scheduling problem.

Machine Shop Suggested Job and Task Sheets. Part II. 21 Advanced Jobs.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of advanced job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-one advanced machine shop job sheets are included. Some or all of this material is provided for each job: an introductory sheet with aim, checking…

Machine Shop Suggested Job and Task Sheets. Part I. 25 Elementary Jobs.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of elementary job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-five simple machine shop job sheets are included. Some or all of this material is provided for each job sheet: an introductory sheet with aim, checking…

A hybrid job-shop scheduling system

Science.gov (United States)

Hellingrath, Bernd; Robbach, Peter; Bayat-Sarmadi, Fahid; Marx, Andreas

1992-01-01

The intention of the scheduling system developed at the Fraunhofer-Institute for Material Flow and Logistics is the support of a scheduler working in a job-shop. Due to the existing requirements for a job-shop scheduling system the usage of flexible knowledge representation and processing techniques is necessary. Within this system the attempt was made to combine the advantages of symbolic AI-techniques with those of neural networks.

Study on multi-objective flexible job-shop scheduling problem considering energy consumption

Directory of Open Access Journals (Sweden)

Zengqiang Jiang

2014-06-01

Full Text Available Purpose: Build a multi-objective Flexible Job-shop Scheduling Problem(FJSP optimization model, in which the makespan, processing cost, energy consumption and cost-weighted processing quality are considered, then Design a Modified Non-dominated Sorting Genetic Algorithm (NSGA-II based on blood variation for above scheduling model.Design/methodology/approach: A multi-objective optimization theory based on Pareto optimal method is used in carrying out the optimization model. NSGA-II is used to solve the model.Findings: By analyzing the research status and insufficiency of multi-objective FJSP, Find that the difference in scheduling will also have an effect on energy consumption in machining process and environmental emissions. Therefore, job-shop scheduling requires not only guaranteeing the processing quality, time and cost, but also optimizing operation plan of machines and minimizing energy consumption.Originality/value: A multi-objective FJSP optimization model is put forward, in which the makespan, processing cost, energy consumption and cost-weighted processing quality are considered. According to above model, Blood-Variation-based NSGA-II (BVNSGA-II is designed. In which, the chromosome mutation rate is determined after calculating the blood relationship between two cross chromosomes, crossover and mutation strategy of NSGA-II is optimized and the prematurity of population is overcome. Finally, the performance of the proposed model and algorithm is evaluated through a case study, and the results proved the efficiency and feasibility of the proposed model and algorithm.

Preventive maintenance optimization for a multi-component system under changing job shop schedule

International Nuclear Information System (INIS)

Zhou Xiaojun; Lu Zhiqiang; Xi Lifeng

2012-01-01

Variability and small lot size is a common feature for many discrete manufacturing processes designed to meet a wide array of customer needs. Because of this, job shop schedule often has to be continuously updated in reaction to changes in production plan. Generally, the aim of preventive maintenance is to ensure production effectiveness and therefore the preventive maintenance models must have the ability to be adaptive to changes in job shop schedule. In this paper, a dynamic opportunistic preventive maintenance model is developed for a multi-component system with considering changes in job shop schedule. Whenever a job is completed, preventive maintenance opportunities arise for all the components in the system. An optimal maintenance practice is dynamically determined by maximizing the short-term cumulative opportunistic maintenance cost savings for the system. The numerical example shows that the scheme obtained by the proposed model can effectively address the preventive maintenance scheduling problem caused by the changes in job shop schedule and is more efficient than the ones based on two other commonly used preventive maintenance models.

Performance evaluation of different types of particle representation procedures of Particle Swarm Optimization in Job-shop Scheduling Problems

Science.gov (United States)

Izah Anuar, Nurul; Saptari, Adi

2016-02-01

This paper addresses the types of particle representation (encoding) procedures in a population-based stochastic optimization technique in solving scheduling problems known in the job-shop manufacturing environment. It intends to evaluate and compare the performance of different particle representation procedures in Particle Swarm Optimization (PSO) in the case of solving Job-shop Scheduling Problems (JSP). Particle representation procedures refer to the mapping between the particle position in PSO and the scheduling solution in JSP. It is an important step to be carried out so that each particle in PSO can represent a schedule in JSP. Three procedures such as Operation and Particle Position Sequence (OPPS), random keys representation and random-key encoding scheme are used in this study. These procedures have been tested on FT06 and FT10 benchmark problems available in the OR-Library, where the objective function is to minimize the makespan by the use of MATLAB software. Based on the experimental results, it is discovered that OPPS gives the best performance in solving both benchmark problems. The contribution of this paper is the fact that it demonstrates to the practitioners involved in complex scheduling problems that different particle representation procedures can have significant effects on the performance of PSO in solving JSP.

Hybrid Genetic Algorithm with Multiparents Crossover for Job Shop Scheduling Problems

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Noor Hasnah Moin

2015-01-01

Full Text Available The job shop scheduling problem (JSSP is one of the well-known hard combinatorial scheduling problems. This paper proposes a hybrid genetic algorithm with multiparents crossover for JSSP. The multiparents crossover operator known as extended precedence preservative crossover (EPPX is able to recombine more than two parents to generate a single new offspring distinguished from common crossover operators that recombine only two parents. This algorithm also embeds a schedule generation procedure to generate full-active schedule that satisfies precedence constraints in order to reduce the search space. Once a schedule is obtained, a neighborhood search is applied to exploit the search space for better solutions and to enhance the GA. This hybrid genetic algorithm is simulated on a set of benchmarks from the literatures and the results are compared with other approaches to ensure the sustainability of this algorithm in solving JSSP. The results suggest that the implementation of multiparents crossover produces competitive results.

Analysis of dispatching rules in a stochastic dynamic job shop manufacturing system with sequence-dependent setup times

Science.gov (United States)

Sharma, Pankaj; Jain, Ajai

2014-12-01

Stochastic dynamic job shop scheduling problem with consideration of sequence-dependent setup times are among the most difficult classes of scheduling problems. This paper assesses the performance of nine dispatching rules in such shop from makespan, mean flow time, maximum flow time, mean tardiness, maximum tardiness, number of tardy jobs, total setups and mean setup time performance measures viewpoint. A discrete event simulation model of a stochastic dynamic job shop manufacturing system is developed for investigation purpose. Nine dispatching rules identified from literature are incorporated in the simulation model. The simulation experiments are conducted under due date tightness factor of 3, shop utilization percentage of 90% and setup times less than processing times. Results indicate that shortest setup time (SIMSET) rule provides the best performance for mean flow time and number of tardy jobs measures. The job with similar setup and modified earliest due date (JMEDD) rule provides the best performance for makespan, maximum flow time, mean tardiness, maximum tardiness, total setups and mean setup time measures.

A tabu search algorithm for scheduling a single robot in a job-shop environment

NARCIS (Netherlands)

Hurink, Johann L.; Knust, S.

1999-01-01

We consider a single-machine scheduling problem which arises as a subproblem in a job-shop environment where the jobs have to be transported between the machines by a single transport robot. The robot scheduling problem may be regarded as a generalization of the travelling-salesman problem with time

A tabu search algorithm for scheduling a single robot in a job-shop environment

NARCIS (Netherlands)

Hurink, Johann L.; Knust, Sigrid

2002-01-01

We consider a single-machine scheduling problem which arises as a subproblem in a job-shop environment where the jobs have to be transported between the machines by a single transport robot. The robot scheduling problem may be regarded as a generalization of the travelling-salesman problem with time

Parallel Branch-and-Bound Methods for the Job Shop Scheduling

DEFF Research Database (Denmark)

Clausen, Jens; Perregaard, Michael

1998-01-01

Job-shop scheduling (JSS) problems are among the more difficult to solve in the class of NP-complete problems. The only successful approach has been branch-and-bound based algorithms, but such algorithms depend heavily on good bound functions. Much work has been done to identify such functions...... for the JSS problem, but with limited success. Even with recent methods, it is still not possible to solve problems substantially larger than 10 machines and 10 jobs. In the current study, we focus on parallel methods for solving JSS problems. We implement two different parallel branch-and-bound algorithms...

On-line scheduling of two-machine open shops where jobs arrive over time

NARCIS (Netherlands)

Chen, B.; Vestjens, A.P.A.; Woeginger, G.J.

1998-01-01

We investigate the problem of on-line scheduling two-machine open shops with the objective of minimizing the makespan.Jobs arrive independently over time, and the existence of a job is not known until its arrival. In the clairvoyant on-line model, the processing requirement of every job becomes

An corrigendum on the paper : Solving the job-shop scheduling problem optimally by dynamic programming (Computers and Operations Research 39(12) (2968–2977) (S0305054812000500) (10.1016/j.cor.2012.02.024))

NARCIS (Netherlands)

van Hoorn, Jelke J.; Nogueira, Agustín; Ojea, Ignacio; Gromicho Dos Santos, Joaquim Antonio

2017-01-01

In [1] an algorithm is proposed for solving the job-shop scheduling problem optimally using a dynamic programming strategy. This is, according to our knowledge, the first exact algorithm for the Job Shop problem which is not based on integer linear programming and branch and bound. Despite the

A Simulated Annealing-Based Heuristic Algorithm for Job Shop Scheduling to Minimize Lateness

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Rui Zhang

2013-04-01

Full Text Available A decomposition-based optimization algorithm is proposed for solving large job shop scheduling problems with the objective of minimizing the maximum lateness. First, we use the constraint propagation theory to derive the orientation of a portion of disjunctive arcs. Then we use a simulated annealing algorithm to find a decomposition policy which satisfies the maximum number of oriented disjunctive arcs. Subsequently, each subproblem (corresponding to a subset of operations as determined by the decomposition policy is successively solved with a simulated annealing algorithm, which leads to a feasible solution to the original job shop scheduling problem. Computational experiments are carried out for adapted benchmark problems, and the results show the proposed algorithm is effective and efficient in terms of solution quality and time performance.

Penerapan Algoritma Genetika Untuk Masalah Penjadwalan Job Shop Pada Lingkungan Industri Pakaian

OpenAIRE

Sitanggang, Hendrik

2011-01-01

Pada industri pakaian khususnya yang proses produksinya berbaur dan multi produk sering mengalami kesulitan pada penjadwalan job shop. Oleh karena itu, perlu diadakan penelitian untuk penjadwalan job shop yang efektif terutama yang proses produksinya berbaur dan multi produk. Pada tulisan ini akan diajukan metode untuk penjadwalan job shop yang berbaur dan multi produk dengan tujuan meminimalkan total pinalti E/T (Earliness/Tardiness) dengan menentukan start pada masing-masing job shop dan ba...

Near-Optimal Heuristics for Just-In-Time Jobs Maximization in Flow Shop Scheduling

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Helio Yochihiro Fuchigami

2018-04-01

Full Text Available The number of just-in-time jobs maximization in a permutation flow shop scheduling problem is considered. A mixed integer linear programming model to represent the problem as well as solution approaches based on enumeration and constructive heuristics were proposed and computationally implemented. Instances with up to 10 jobs and five machines are solved by the mathematical model in an acceptable running time (3.3 min on average while the enumeration method consumes, on average, 1.5 s. The 10 constructive heuristics proposed show they are practical especially for large-scale instances (up to 100 jobs and 20 machines, with very good-quality results and efficient running times. The best two heuristics obtain near-optimal solutions, with only 0.6% and 0.8% average relative deviations. They prove to be better than adaptations of the NEH heuristic (well-known for providing very good solutions for makespan minimization in flow shop for the considered problem.

Processing time tolerance-based ACO algorithm for solving job-shop scheduling problem

Science.gov (United States)

Luo, Yabo; Waden, Yongo P.

2017-06-01

Ordinarily, Job Shop Scheduling Problem (JSSP) is known as NP-hard problem which has uncertainty and complexity that cannot be handled by a linear method. Thus, currently studies on JSSP are concentrated mainly on applying different methods of improving the heuristics for optimizing the JSSP. However, there still exist many problems for efficient optimization in the JSSP, namely, low efficiency and poor reliability, which can easily trap the optimization process of JSSP into local optima. Therefore, to solve this problem, a study on Ant Colony Optimization (ACO) algorithm combined with constraint handling tactics is carried out in this paper. Further, the problem is subdivided into three parts: (1) Analysis of processing time tolerance-based constraint features in the JSSP which is performed by the constraint satisfying model; (2) Satisfying the constraints by considering the consistency technology and the constraint spreading algorithm in order to improve the performance of ACO algorithm. Hence, the JSSP model based on the improved ACO algorithm is constructed; (3) The effectiveness of the proposed method based on reliability and efficiency is shown through comparative experiments which are performed on benchmark problems. Consequently, the results obtained by the proposed method are better, and the applied technique can be used in optimizing JSSP.

Three hybridization models based on local search scheme for job shop scheduling problem

Science.gov (United States)

Balbi Fraga, Tatiana

2015-05-01

This work presents three different hybridization models based on the general schema of Local Search Heuristics, named Hybrid Successive Application, Hybrid Neighborhood, and Hybrid Improved Neighborhood. Despite similar approaches might have already been presented in the literature in other contexts, in this work these models are applied to analyzes the solution of the job shop scheduling problem, with the heuristics Taboo Search and Particle Swarm Optimization. Besides, we investigate some aspects that must be considered in order to achieve better solutions than those obtained by the original heuristics. The results demonstrate that the algorithms derived from these three hybrid models are more robust than the original algorithms and able to get better results than those found by the single Taboo Search.

Sequencing, lot sizing and scheduling in job shops: the common cycle approach

NARCIS (Netherlands)

Ouenniche, J.; Boctor, F.F.

1998-01-01

This paper deals with the multi-product, finite horizon, static demand, sequencing, lot sizing and scheduling problem in a job shop environment where the objective is to minimize the sum of setup and inventory holding costs while satisfying the demand with no backlogging. To solve this problem, we

Performance Implications of Buffer Overflow as a Key (Disturbing) Element in the Flow Control of a Job/Flow Shop Facility

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

From time to time most real life job/flow shops will experience more or less severe buffer problems in relation to the operation at its various stations in the shop. Due to temporary non-predictable variations in the job flow intensity the assigned buffer space in front of a given critical station...... to temporary buffer overflow situations. This paper will investigate the impact of buffer overflow on several key performance measures of relevance to the overall operation of a job/flow shop facility. Several simple job/flow shop structures will be considered in this paper including re-entrant system set......-ups (a re-entrant system is a system where some of the job-routes revisit a given station more than once)....

Performance Implications of Buffer overflow as a key (Disturbing) Element in the Flow Control of a Job/Flow Shop Facility

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

From time to time most real life job/flow shops will experience more or less severe buffer problems in relation to the operation at its various stations in the shop. Due to temporary non-predictable variations in the job flow intensity the assigned buffer space in front of a given critical station...... to temporary buffer overflow situations. This paper will investigate the impact of buffer overflow on several key performance measures of relevance to the overall operation of a job/flow shop facility. Several simple job/flow shop structures will be considered in this paper including re-entrant system set......-ups (a re-entrant system is a system where some of the job-routes revisit a given station more than once)....

The comparison of predictive scheduling algorithms for different sizes of job shop scheduling problems

Science.gov (United States)

Paprocka, I.; Kempa, W. M.; Grabowik, C.; Kalinowski, K.; Krenczyk, D.

2016-08-01

In the paper a survey of predictive and reactive scheduling methods is done in order to evaluate how the ability of prediction of reliability characteristics influences over robustness criteria. The most important reliability characteristics are: Mean Time to Failure, Mean Time of Repair. Survey analysis is done for a job shop scheduling problem. The paper answers the question: what method generates robust schedules in the case of a bottleneck failure occurrence before, at the beginning of planned maintenance actions or after planned maintenance actions? Efficiency of predictive schedules is evaluated using criteria: makespan, total tardiness, flow time, idle time. Efficiency of reactive schedules is evaluated using: solution robustness criterion and quality robustness criterion. This paper is the continuation of the research conducted in the paper [1], where the survey of predictive and reactive scheduling methods is done only for small size scheduling problems.

Constraint satisfaction adaptive neural network and heuristics combined approaches for generalized job-shop scheduling.

Science.gov (United States)

Yang, S; Wang, D

2000-01-01

This paper presents a constraint satisfaction adaptive neural network, together with several heuristics, to solve the generalized job-shop scheduling problem, one of NP-complete constraint satisfaction problems. The proposed neural network can be easily constructed and can adaptively adjust its weights of connections and biases of units based on the sequence and resource constraints of the job-shop scheduling problem during its processing. Several heuristics that can be combined with the neural network are also presented. In the combined approaches, the neural network is used to obtain feasible solutions, the heuristic algorithms are used to improve the performance of the neural network and the quality of the obtained solutions. Simulations have shown that the proposed neural network and its combined approaches are efficient with respect to the quality of solutions and the solving speed.

An Artificial Bee Colony Algorithm for the Job Shop Scheduling Problem with Random Processing Times

Directory of Open Access Journals (Sweden)

Rui Zhang

2011-09-01

Full Text Available Due to the influence of unpredictable random events, the processing time of each operation should be treated as random variables if we aim at a robust production schedule. However, compared with the extensive research on the deterministic model, the stochastic job shop scheduling problem (SJSSP has not received sufficient attention. In this paper, we propose an artificial bee colony (ABC algorithm for SJSSP with the objective of minimizing the maximum lateness (which is an index of service quality. First, we propose a performance estimate for preliminary screening of the candidate solutions. Then, the K-armed bandit model is utilized for reducing the computational burden in the exact evaluation (through Monte Carlo simulation process. Finally, the computational results on different-scale test problems validate the effectiveness and efficiency of the proposed approach.

REDUCING LEAD TIME USING FUZZY LOGIC AT JOB SHOP

Directory of Open Access Journals (Sweden)

EMİN GÜNDOĞAR

2000-06-01

Full Text Available One problem encountering at the job shop scheduling is minimum production size of machine is different from each another. This case increases lead time. A new approach was improved to reduce lead time. In this new approach, the parts, which materials are in stock and orders coming very frequently are assigned to machine to reduce lead time. Due the fact that there are a lot of machine and orders, it is possible to become so1ne probletns. In this paper, fuzzy logic is used to cope with this problem. New approach was simulated at the job sop that has owner 15 machinery and 50 orders. Simulation results showed that new approach reduced lead time between 27.89% and 32.36o/o

Overlap Algorithms in Flexible Job-shop Scheduling

Directory of Open Access Journals (Sweden)

Celia Gutierrez

2014-06-01

Full Text Available The flexible Job-shop Scheduling Problem (fJSP considers the execution of jobs by a set of candidate resources while satisfying time and technological constraints. This work, that follows the hierarchical architecture, is based on an algorithm where each objective (resource allocation, start-time assignment is solved by a genetic algorithm (GA that optimizes a particular fitness function, and enhances the results by the execution of a set of heuristics that evaluate and repair each scheduling constraint on each operation. The aim of this work is to analyze the impact of some algorithmic features of the overlap constraint heuristics, in order to achieve the objectives at a highest degree. To demonstrate the efficiency of this approach, experimentation has been performed and compared with similar cases, tuning the GA parameters correctly.

Simulation as a planning tool for job-shop production environment

Science.gov (United States)

Maram, Venkataramana; Nawawi, Mohd Kamal Bin Mohd; Rahman, Syariza Abdul; Sultan, Sultan Juma

2015-12-01

In this paper, we made an attempt to use discrete event simulation software ARENA® as a planning tool for job shop production environment. We considered job shop produces three types of Jigs with different sequence of operations to study and improve shop floor performance. The sole purpose of the study is to identifying options to improve machines utilization, reducing job waiting times at bottleneck machines. First, the performance of the existing system was evaluated by using ARENA®. Then identified improvement opportunities by analyzing base system results. Second, updated the model with most economical options. The proposed new system outperforms with that of the current base system by 816% improvement in delay times at paint shop by increase 2 to 3 and Jig cycle time reduces by Jig1 92%, Jig2 65% and Jig3 41% and hence new proposal was recommended.

REPAIR SHOP JOB SCHEDULING WITH PARALLEL OPERATORS AND MULTIPLE CONSTRAINTS USING SIMULATED ANNEALING

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N. Shivasankaran

2013-04-01

Full Text Available Scheduling problems are generally treated as NP andash; complete combinatorial optimization problems which is a multi-objective and multi constraint one. Repair shop Job sequencing and operator allocation is one such NP andash; complete problem. For such problems, an efficient technique is required that explores a wide range of solution space. This paper deals with Simulated Annealing Technique, a Meta - heuristic to solve the complex Car Sequencing and Operator Allocation problem in a car repair shop. The algorithm is tested with several constraint settings and the solution quality exceeds the results reported in the literature with high convergence speed and accuracy. This algorithm could be considered as quite effective while other heuristic routine fails.

JOB SHOP METHODOLOGY BASED ON AN ANT COLONY

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OMAR CASTRILLON

2009-01-01

Full Text Available The purpose of this study is to reduce the total process time (Makespan and to increase the machines working time, in a job shop environment, using a heuristic based on ant colony optimization. This work is developed in two phases: The first stage describes the identification and definition of heuristics for the sequential processes in the job shop. The second stage shows the effectiveness of the system in the traditional programming of production. A good solution, with 99% efficiency is found using this technique.

Multi-objective flexible job-shop scheduling problem using modified discrete particle swarm optimization.

Science.gov (United States)

Huang, Song; Tian, Na; Wang, Yan; Ji, Zhicheng

2016-01-01

Taking resource allocation into account, flexible job shop problem (FJSP) is a class of complex scheduling problem in manufacturing system. In order to utilize the machine resources rationally, multi-objective particle swarm optimization (MOPSO) integrating with variable neighborhood search is introduced to address FJSP efficiently. Firstly, the assignment rules (AL) and dispatching rules (DR) are provided to initialize the population. And then special discrete operators are designed to produce new individuals and earliest completion machine (ECM) is adopted in the disturbance operator to escape the optima. Secondly, personal-best archives (cognitive memories) and global-best archive (social memory), which are updated by the predefined non-dominated archive update strategy, are simultaneously designed to preserve non-dominated individuals and select personal-best positions and the global-best position. Finally, three neighborhoods are provided to search the neighborhoods of global-best archive for enhancing local search ability. The proposed algorithm is evaluated by using Kacem instances and Brdata instances, and a comparison with other approaches shows the effectiveness of the proposed algorithm for FJSP.

Genetic programming for evolving due-date assignment models in job shop environments.

Science.gov (United States)

Nguyen, Su; Zhang, Mengjie; Johnston, Mark; Tan, Kay Chen

2014-01-01

Due-date assignment plays an important role in scheduling systems and strongly influences the delivery performance of job shops. Because of the stochastic and dynamic nature of job shops, the development of general due-date assignment models (DDAMs) is complicated. In this study, two genetic programming (GP) methods are proposed to evolve DDAMs for job shop environments. The experimental results show that the evolved DDAMs can make more accurate estimates than other existing dynamic DDAMs with promising reusability. In addition, the evolved operation-based DDAMs show better performance than the evolved DDAMs employing aggregate information of jobs and machines.

Bi-Objective Flexible Job-Shop Scheduling Problem Considering Energy Consumption under Stochastic Processing Times.

Science.gov (United States)

Yang, Xin; Zeng, Zhenxiang; Wang, Ruidong; Sun, Xueshan

2016-01-01

This paper presents a novel method on the optimization of bi-objective Flexible Job-shop Scheduling Problem (FJSP) under stochastic processing times. The robust counterpart model and the Non-dominated Sorting Genetic Algorithm II (NSGA-II) are used to solve the bi-objective FJSP with consideration of the completion time and the total energy consumption under stochastic processing times. The case study on GM Corporation verifies that the NSGA-II used in this paper is effective and has advantages to solve the proposed model comparing with HPSO and PSO+SA. The idea and method of the paper can be generalized widely in the manufacturing industry, because it can reduce the energy consumption of the energy-intensive manufacturing enterprise with less investment when the new approach is applied in existing systems.

Generation of Look-Up Tables for Dynamic Job Shop Scheduling Decision Support Tool

Science.gov (United States)

Oktaviandri, Muchamad; Hassan, Adnan; Mohd Shaharoun, Awaluddin

2016-02-01

Majority of existing scheduling techniques are based on static demand and deterministic processing time, while most job shop scheduling problem are concerned with dynamic demand and stochastic processing time. As a consequence, the solutions obtained from the traditional scheduling technique are ineffective wherever changes occur to the system. Therefore, this research intends to develop a decision support tool (DST) based on promising artificial intelligent that is able to accommodate the dynamics that regularly occur in job shop scheduling problem. The DST was designed through three phases, i.e. (i) the look-up table generation, (ii) inverse model development and (iii) integration of DST components. This paper reports the generation of look-up tables for various scenarios as a part in development of the DST. A discrete event simulation model was used to compare the performance among SPT, EDD, FCFS, S/OPN and Slack rules; the best performances measures (mean flow time, mean tardiness and mean lateness) and the job order requirement (inter-arrival time, due dates tightness and setup time ratio) which were compiled into look-up tables. The well-known 6/6/J/Cmax Problem from Muth and Thompson (1963) was used as a case study. In the future, the performance measure of various scheduling scenarios and the job order requirement will be mapped using ANN inverse model.

The performance of workload control concepts in job shops : Improving the release method

NARCIS (Netherlands)

Land, MJ; Gaalman, GJC

1998-01-01

A specific class of production control concepts for jobs shops is based on the principles of workload control. Practitioners emphasise the importance of workload control. However, order release methods that reduce the workload on the shop floor show poor due date performance in job shop simulations.

Job shop scheduling by local search

NARCIS (Netherlands)

Aarts, E.H.L.; Lenstra, J.K.; Laarhoven, van P.J.M.; Ulder, N.L.J.

1992-01-01

We present a computational performance analysis of local search algorithms for job shop scheduling. The algorithms under investigation are iterative improvement, simulated annealing, threshold accepting and genetic local search. Our study shows that simulated annealing performs best in the sense

Comparing Mixed & Integer Programming vs. Constraint Programming by solving Job-Shop Scheduling Problems

Directory of Open Access Journals (Sweden)

Renata Melo e Silva de Oliveira

2015-03-01

Full Text Available Scheduling is a key factor for operations management as well as for business success. From industrial Job-shop Scheduling problems (JSSP, many optimization challenges have emerged since de 1960s when improvements have been continuously required such as bottlenecks allocation, lead-time reductions and reducing response time to requests.  With this in perspective, this work aims to discuss 3 different optimization models for minimizing Makespan. Those 3 models were applied on 17 classical problems of examples JSSP and produced different outputs.  The first model resorts on Mixed and Integer Programming (MIP and it resulted on optimizing 60% of the studied problems. The other models were based on Constraint Programming (CP and approached the problem in two different ways: a model CP1 is a standard IBM algorithm whereof restrictions have an interval structure that fail to solve 53% of the proposed instances, b Model CP-2 approaches the problem with disjunctive constraints and optimized 88% of the instances. In this work, each model is individually analyzed and then compared considering: i Optimization success performance, ii Computational processing time, iii Greatest Resource Utilization and, iv Minimum Work-in-process Inventory. Results demonstrated that CP-2 presented best results on criteria i and ii, but MIP was superior on criteria iii and iv and those findings are discussed at the final section of this work.

Scheduling job shop - A case study

Science.gov (United States)

Abas, M.; Abbas, A.; Khan, W. A.

2016-08-01

The scheduling in job shop is important for efficient utilization of machines in the manufacturing industry. There are number of algorithms available for scheduling of jobs which depend on machines tools, indirect consumables and jobs which are to be processed. In this paper a case study is presented for scheduling of jobs when parts are treated on available machines. Through time and motion study setup time and operation time are measured as total processing time for variety of products having different manufacturing processes. Based on due dates different level of priority are assigned to the jobs and the jobs are scheduled on the basis of priority. In view of the measured processing time, the times for processing of some new jobs are estimated and for efficient utilization of the machines available an algorithm is proposed and validated.

JOB SHOP SCHEDULING BIOBJETIVO MEDIANTE ENFRIAMIENTO SIMULADO Y ENFOQUE DE PARETO JOB-SHOP SCHEDULING: BIO-OBJECTIVE THROUGH SIMULATED COOLING AND PARETO PRINCIPLE

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Juan Carlos Osorio

2012-12-01

Full Text Available El problema del scheduling es uno de los problemas más ampliamente tratados en la literatura; sin embargo, es un problema complejo NP hard. Cuando, además, se involucra más de un objetivo, este problema se convierte en uno de los más complejos en el campo de la investigación de operaciones. Se presenta entonces un modelo biobjetivo para el job shop scheduling que incluye el makespan y el tiempo de flujo medio. Para resolver el modelo se ha utilizado una propuesta que incluye el uso del meta-heurístico Recocido Simulado (SA y el enfoque de Pareto. Este modelo es evaluado en tres problemas presentados en la literatura de tamaños 6x6, 10x5 y 10x10. Los resultados del modelo se comparan con otros meta-heurísticos y se encuentra que este modelo presenta buenos resultados en los tres problemas evaluados.The scheduling problem is one of the most widely treated problems in literature; however, it is an NP hard complex problem. Also, when more than one objective is involved, this problem becomes one of the most complex ones in the field of operations research. A bio-objective model is then emerged for the Job-Shop Scheduling, including makespan and mean flow time. For solving the model a proposal which includes the use of Simulated Annealing (SA metaheuristic and Pareto Principle. This model is evaluated in three problems described in literature with the following sizes: 6x6, 10x5 and 10x10. Results of the model are compared to other metaheuristics and it has been found that this model shows good results in the three problems evaluated.

A Variable Interval Rescheduling Strategy for Dynamic Flexible Job Shop Scheduling Problem by Improved Genetic Algorithm

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Lei Wang

2017-01-01

Full Text Available In real-world manufacturing systems, production scheduling systems are often implemented under random or dynamic events like machine failure, unexpected processing times, stochastic arrival of the urgent orders, cancellation of the orders, and so on. These dynamic events will lead the initial scheduling scheme to be nonoptimal and/or infeasible. Hence, appropriate dynamic rescheduling approaches are needed to overcome the dynamic events. In this paper, we propose a dynamic rescheduling method based on variable interval rescheduling strategy (VIRS to deal with the dynamic flexible job shop scheduling problem considering machine failure, urgent job arrival, and job damage as disruptions. On the other hand, an improved genetic algorithm (GA is proposed for minimizing makespan. In our improved GA, a mix of random initialization population by combining initialization machine and initialization operation with random initialization is designed for generating high-quality initial population. In addition, the elitist strategy (ES and improved population diversity strategy (IPDS are used to avoid falling into the local optimal solution. Experimental results for static and several dynamic events in the FJSP show that our method is feasible and effective.

Scheduling stochastic two-machine flow shop problems to minimize expected makespan

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Mehdi Heydari

2013-07-01

Full Text Available During the past few years, despite tremendous contribution on deterministic flow shop problem, there are only limited number of works dedicated on stochastic cases. This paper examines stochastic scheduling problems in two-machine flow shop environment for expected makespan minimization where processing times of jobs are normally distributed. Since jobs have stochastic processing times, to minimize the expected makespan, the expected sum of the second machine’s free times is minimized. In other words, by minimization waiting times for the second machine, it is possible to reach the minimum of the objective function. A mathematical method is proposed which utilizes the properties of the normal distributions. Furthermore, this method can be used as a heuristic method for other distributions, as long as the means and variances are available. The performance of the proposed method is explored using some numerical examples.

A Novel Memetic Algorithm Based on Decomposition for Multiobjective Flexible Job Shop Scheduling Problem

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Chun Wang

2017-01-01

Full Text Available A novel multiobjective memetic algorithm based on decomposition (MOMAD is proposed to solve multiobjective flexible job shop scheduling problem (MOFJSP, which simultaneously minimizes makespan, total workload, and critical workload. Firstly, a population is initialized by employing an integration of different machine assignment and operation sequencing strategies. Secondly, multiobjective memetic algorithm based on decomposition is presented by introducing a local search to MOEA/D. The Tchebycheff approach of MOEA/D converts the three-objective optimization problem to several single-objective optimization subproblems, and the weight vectors are grouped by K-means clustering. Some good individuals corresponding to different weight vectors are selected by the tournament mechanism of a local search. In the experiments, the influence of three different aggregation functions is first studied. Moreover, the effect of the proposed local search is investigated. Finally, MOMAD is compared with eight state-of-the-art algorithms on a series of well-known benchmark instances and the experimental results show that the proposed algorithm outperforms or at least has comparative performance to the other algorithms.

Integrating make-to-order and make-to-stock in job shop control

NARCIS (Netherlands)

Beemsterboer, Bart; Land, Martin; Teunter, Ruud; Bokhorst, Jos

2017-01-01

Demand fluctuations in make-to-order job shops lead to utilisation fluctuations and delivery delays, particularly in periods with high demand. Many job shop production companies therefore include some standardised products in their product mix and use a hybrid make-to-order/ make-to-stock production

A Review On Job Shop Scheduling Using Non-Conventional Optimization Algorithm

OpenAIRE

K.Mallikarjuna; Venkatesh.G

2014-01-01

A great deal of research has been focused on solving job shop scheduling problem (∫J), over the last four decades, resulting in a wide variety of approaches. Recently much effort has been concentrated on hybrid methods to solve ∫J, as a single technique cannot solve this stubborn problem. As a result much effort has recently been concentrated on techniques that lead to combinatorial optimization methods and a meta-strategy which guides the search out of local optima. In this p...

A Distributed Particle Swarm Optimization Zlgorithmfor Flexible Job-hop Scheduling Problem

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LIU Sheng--hui

2017-06-01

Full Text Available According to the characteristics of the Flexible job shop scheduling problem the minimum makespan as measures we proposed a distributed particle swarm optimization algorithm aiming to solve flexible job shop scheduling problem. The algorithm adopts the method of distributed ideas to solve problems and we are established for two multi agent particle swarm optimization model in this algorithm it can solve the traditional particle swarm optimization algorithm when making decisions in real time according to the emergencies. Finally some benthmark problems were experimented and the results are compared with the traditional algorithm. Experimental results proved that the developed distributed PSO is enough effective and efficient to solve the FJSP and it also verified the reasonableness of the multi}gent particle swarm optimization model.

A controlled genetic algorithm by fuzzy logic and belief functions for job-shop scheduling.

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Hajri, S; Liouane, N; Hammadi, S; Borne, P

2000-01-01

Most scheduling problems are highly complex combinatorial problems. However, stochastic methods such as genetic algorithm yield good solutions. In this paper, we present a controlled genetic algorithm (CGA) based on fuzzy logic and belief functions to solve job-shop scheduling problems. For better performance, we propose an efficient representational scheme, heuristic rules for creating the initial population, and a new methodology for mixing and computing genetic operator probabilities.

EFFICIENT MULTI-OBJECTIVE EVOLUTIONARY ALGORITHM FOR JOB SHOP SCHEDULING

Institute of Scientific and Technical Information of China (English)

Lei Deming; Wu Zhiming

2005-01-01

A new representation method is first presented based on priority rules. According to this method, each entry in the chromosome indicates that in the procedure of the Giffler and Thompson (GT) algorithm, the conflict occurring in the corresponding machine is resolved by the corresponding priority rule. Then crowding-measure multi-objective evolutionary algorithm (CMOEA) is designed,in which both archive maintenance and fitness assignment use crowding measure. Finally the comparisons between CMOEA and SPEA in solving 15 scheduling problems demonstrate that CMOEA is suitable to job shop scheduling.

Shopping Problems among High School Students

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Grant, Jon E.; Potenza, Marc N.; Krishnan-Sarin, Suchitra; Cavallo, Dana A.; Desai, Rani A.

2010-01-01

Background Although shopping behavior among adolescents is normal, for some the shopping becomes problematic. An assessment of adolescent shopping behavior along a continuum of severity and its relationship to other behaviors and health issues is incompletely understood. Methods A large sample of high school students (n=3999) was examined using a self-report survey with 153 questions concerning demographic characteristics, shopping behaviors, other health behaviors including substance use, and functioning variables such as grades and violent behavior. Results The overall prevalence of problem shopping was 3.5% (95%CI: 2.93–4.07). Regular smoking, marijuana and other drug use, sadness and hopelessness, and antisocial behaviors (e.g., fighting, carrying weapons) were associated with problem shopping behavior in both boys and girls. Heavy alcohol use was significantly associated with problem shopping only in girls. Conclusion Problem shopping appears fairly common among high school students and is associated with symptoms of depression and a range of potentially addictive and antisocial behaviors. Significant distress and diminished behavioral control suggest that excessive shopping may often have significant associated morbidity. Additional research is needed to develop specific prevention and treatment strategies for adolescents who report problems with shopping. PMID:21497217

Shopping problems among high school students.

Science.gov (United States)

Grant, Jon E; Potenza, Marc N; Krishnan-Sarin, Suchitra; Cavallo, Dana A; Desai, Rani A

2011-01-01

Although shopping behavior among adolescents is normal, for some, the shopping becomes problematic. An assessment of adolescent shopping behavior along a continuum of severity and its relationship to other behaviors and health issues is incompletely understood. A large sample of high school students (n = 3999) was examined using a self-report survey with 153 questions concerning demographic characteristics, shopping behaviors, other health behaviors including substance use, and functioning variables such as grades and violent behavior. The overall prevalence of problem shopping was 3.5% (95% CI, 2.93-4.07). Regular smoking, marijuana and other drug use, sadness and hopelessness, and antisocial behaviors (e.g., fighting, carrying weapons) were associated with problem shopping behavior in both boys and girls. Heavy alcohol use was significantly associated with problem shopping only in girls. Problem shopping appears fairly common among high school students and is associated with symptoms of depression and a range of potentially addictive and antisocial behaviors. Significant distress and diminished behavioral control suggest that excessive shopping may often have significant associated morbidity. Additional research is needed to develop specific prevention and treatment strategies for adolescents who report problems with shopping. Copyright © 2011 Elsevier Inc. All rights reserved.

Método para definição de layout em sistemas job-shop baseado em dados históricos Historical data-based job-shop layout systems definition method

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Maurício Tomelin

2010-01-01

Full Text Available O presente trabalho propõe um método para a solução do problema de definição de layout tipo job-shop baseado em dados históricos de produção, recursos disponíveis e características de produção. Os parâmetros utilizados foram a quantidade total e a frequência de vendas, a lucratividade, o tempo total de processamento e o tempo de espera de cada produto, gerando assim a classificação dos produtos. Os roteiros de produção foram comparados e, em função dos parâmetros, foi determinado o grau de importância de cada ligação entre os recursos. As ligações foram submetidas a um modelo matemático para a determinação da posição de cada recurso no layout. O método desenvolvido foi aplicado a uma empresa de usinagem com característica de job-shop. Os dados submetidos ao método permitiram uma sugestão de layout que tem como objetivo minimizar a distância dos recursos de processamento.This paper proposes a method for solving the job-shop layout problem definition, based on historical production data, available resources and production characteristics. The products were classified according to total sales, sales frequency, profitability, total processing time and stand-by time. The production path was compared and the degree of importance of each link between resources was determined. Path comparisons were made to quantify the same routes and the route differences, generating similar routes. The links were submitted to a mathematical model to determine the position of resources in the layout. The method developed was applied to a machining company with a job-shop profile. When the company's data was subjected to the method, it enabled the development of a layout, the main goal of which was to minimize distances between product-processing resources.

The Effects of Machine Load Sitnations on Performance of Job Shop and Group Scheduling

OpenAIRE

Torkul, O.

2018-01-01

Perfonnance of job shop and group scheduling ndermulti­natch work input environment was exarnined against two nachine load (light and high load) situations. n order to conduct the analysis, a deterministic computer ;im ulation program was written and used. A job shop {JS) model is applied to the shop floor area and :ompared with a simulation of a similar proposal except hat group technology (GT) model was used in the shop loor area instead. )etailed analysis of the results from applying diffe...

The Effects of Machine Load Sitnations on Performance of Job Shop and Group Scheduling

OpenAIRE

O.TORKUL TORKUL

1998-01-01

Perfonnance of job shop and group scheduling ndermulti­natch work input environment was exarnined against two nachine load (light and high load) situations. n order to conduct the analysis, a deterministic computer ;im ulation program was written and used. A job shop {JS) model is applied to the shop floor area and :ompared with a simulation of a similar proposal except hat group technology (GT) model was used in the shop loor area instead. )etailed analysis of the results from applying diffe...

Permutation flow-shop scheduling problem to optimize a quadratic objective function

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Ren, Tao; Zhao, Peng; Zhang, Da; Liu, Bingqian; Yuan, Huawei; Bai, Danyu

2017-09-01

A flow-shop scheduling model enables appropriate sequencing for each job and for processing on a set of machines in compliance with identical processing orders. The objective is to achieve a feasible schedule for optimizing a given criterion. Permutation is a special setting of the model in which the processing order of the jobs on the machines is identical for each subsequent step of processing. This article addresses the permutation flow-shop scheduling problem to minimize the criterion of total weighted quadratic completion time. With a probability hypothesis, the asymptotic optimality of the weighted shortest processing time schedule under a consistency condition (WSPT-CC) is proven for sufficiently large-scale problems. However, the worst case performance ratio of the WSPT-CC schedule is the square of the number of machines in certain situations. A discrete differential evolution algorithm, where a new crossover method with multiple-point insertion is used to improve the final outcome, is presented to obtain high-quality solutions for moderate-scale problems. A sequence-independent lower bound is designed for pruning in a branch-and-bound algorithm for small-scale problems. A set of random experiments demonstrates the performance of the lower bound and the effectiveness of the proposed algorithms.

Flow-shop scheduling problem under uncertainties: Review and trends

OpenAIRE

Eliana María González-Neira; Jairo R. Montoya-Torres; David Barrera

2017-01-01

Among the different tasks in production logistics, job scheduling is one of the most important at the operational decision-making level to enable organizations to achieve competiveness. Scheduling consists in the allocation of limited resources to activities over time in order to achieve one or more optimization objectives. Flow-shop (FS) scheduling problems encompass the sequencing processes in environments in which the activities or operations are performed in a serial flow. This type of co...

Traitement d'un problème de type FJSP (Flexible Job Shop ...

African Journals Online (AJOL)

Dans cet article, nous avons étudié le problème d'optimisation d'une cellule de production flexible de type FJSP (flexible job-shop scheduling problem), dont le contrôle est très complexe. Parmi les multiples techniques et méthodes utilisées pour l‟étude de ce type de problème, il y a celles qui relèvent de la recherche ...

Busca tabu para a programação de tarefas em job shop com datas de entrega

OpenAIRE

Cintia Rigão Scrich

1997-01-01

Resumo: Este trabalho trata do problema de programação de tarefas nos ambientes job shop tradicional e job shop flexível com o objetivo de minimizar o atraso total das tarefas. A principal diferença do job shop flexível em relação ao job shop tradicional é que cada operação possui um conjunto de máquinas alternativas onde pode ser processada. Para cada um dos problemas é desenvolvida uma heurística guiada pela metaheurística Busca Tabu. Estratégias de diversificação e intensificação para a bu...

A review of scheduling problem and resolution methods in flexible flow shop

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Tian-Soon Lee

2019-01-01

Full Text Available The Flexible flow shop (FFS is defined as a multi-stage flow shops with multiple parallel machines. FFS scheduling problem is a complex combinatorial problem which has been intensively studied in many real world industries. This review paper gives a comprehensive exploration review on the FFS scheduling problem and guides the reader by considering and understanding different environmental assumptions, system constraints and objective functions for future research works. The published papers are classified into two categories. First is the FFS system characteristics and constraints including the problem differences and limitation defined by different studies. Second, the scheduling performances evaluation are elaborated and categorized into time, job and multi related objectives. In addition, the resolution approaches that have been used to solve FFS scheduling problems are discussed. This paper gives a comprehensive guide for the reader with respect to future research work on the FFS scheduling problem.

Proportionate Flow Shop Games

NARCIS (Netherlands)

Estevez Fernandez, M.A.; Mosquera, M.A.; Borm, P.E.M.; Hamers, H.J.M.

2006-01-01

In a proportionate flow shop problem several jobs have to be processed through a fixed sequence of machines and the processing time of each job is equal on all machines.By identifying jobs with agents, whose costs linearly depend on the completion time of their jobs, and assuming an initial

A Generalized Ant Colony Algorithm for Job一shop Scheduling Problem

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ZHANG Hong-Guo

2017-02-01

Full Text Available Aiming at the problem of ant colony algorithm for solving Job一shop scheduling problem. Considering the complexity of the algorithm that uses disjunctive graph to describe the relationship between workpiece processing. To solve the problem of optimal solution，a generalized ant colony algorithm is proposed. Under the premise of considering constrained relationship between equipment and process，the pheromone update mechanism is applied to solve Job-shop scheduling problem，so as to improve the quality of the solution. In order to improve the search efficiency，according to the state transition rules of ant colony algorithm，this paper makes a detailed study on the selection and improvement of the parameters in the algorithm，and designs the pheromone update strategy. Experimental results show that a generalized ant colony algorithm is more feasible and more effective. Compared with other algorithms in the literature，the results prove that the algorithm improves in computing the optimal solution and convergence speed.

PENGEMBANGAN ALGORITMA PENJADUALAN PRODUKSI JOB SHOP UNTUK MEMINIMUMKAN TOTAL BIAYA EARLINESS DAN TARDINESS

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Dian Retno Sari Dewi

2005-12-01

Full Text Available This paper develops job shop production scheduling using Non Delay algorithm through forward and backward-forward algorithm to minimize total earliness and tardiness costs. Backward approach has some disadvantages, such as, if the job is scheduled in backward, there is a possibility that the infeasible situation occurs, in which the job is scheduled at t<0. This paper used hypothetic data generated randomly. This job shop scheduling algorithm development was validated using LINDO software to check the effectiveness heuristic method, compared with the optimation method. The validation proves that the result of backward-forward scheduling method is better than the result of forward scheduling method.

A PMBGA to Optimize the Selection of Rules for Job Shop Scheduling Based on the Giffler-Thompson Algorithm

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Rui Zhang

2012-01-01

Full Text Available Most existing research on the job shop scheduling problem has been focused on the minimization of makespan (i.e., the completion time of the last job. However, in the fiercely competitive market nowadays, delivery punctuality is more important for maintaining a high service reputation. So in this paper, we aim at solving job shop scheduling problems with the total weighted tardiness objective. Several dispatching rules are adopted in the Giffler-Thompson algorithm for constructing active schedules. It is noticeable that the rule selections for scheduling consecutive operations are not mutually independent but actually interrelated. Under such circumstances, a probabilistic model-building genetic algorithm (PMBGA is proposed to optimize the sequence of selected rules. First, we use Bayesian networks to model the distribution characteristics of high-quality solutions in the population. Then, the new generation of individuals is produced by sampling the established Bayesian network. Finally, some elitist individuals are further improved by a special local search module based on parameter perturbation. The superiority of the proposed approach is verified by extensive computational experiments and comparisons.

Evolutionary Hybrid Particle Swarm Optimization Algorithm for Solving NP-Hard No-Wait Flow Shop Scheduling Problems

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Laxmi A. Bewoor

2017-10-01

Full Text Available The no-wait flow shop is a flowshop in which the scheduling of jobs is continuous and simultaneous through all machines without waiting for any consecutive machines. The scheduling of a no-wait flow shop requires finding an appropriate sequence of jobs for scheduling, which in turn reduces total processing time. The classical brute force method for finding the probabilities of scheduling for improving the utilization of resources may become trapped in local optima, and this problem can hence be observed as a typical NP-hard combinatorial optimization problem that requires finding a near optimal solution with heuristic and metaheuristic techniques. This paper proposes an effective hybrid Particle Swarm Optimization (PSO metaheuristic algorithm for solving no-wait flow shop scheduling problems with the objective of minimizing the total flow time of jobs. This Proposed Hybrid Particle Swarm Optimization (PHPSO algorithm presents a solution by the random key representation rule for converting the continuous position information values of particles to a discrete job permutation. The proposed algorithm initializes population efficiently with the Nawaz-Enscore-Ham (NEH heuristic technique and uses an evolutionary search guided by the mechanism of PSO, as well as simulated annealing based on a local neighborhood search to avoid getting stuck in local optima and to provide the appropriate balance of global exploration and local exploitation. Extensive computational experiments are carried out based on Taillard’s benchmark suite. Computational results and comparisons with existing metaheuristics show that the PHPSO algorithm outperforms the existing methods in terms of quality search and robustness for the problem considered. The improvement in solution quality is confirmed by statistical tests of significance.

A New Artificial Immune System Algorithm for Multiobjective Fuzzy Flow Shop Problems

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Cengiz Kahraman

2009-12-01

Full Text Available In this paper a new artificial immune system (AIS algorithm is proposed to solve multi objective fuzzy flow shop scheduling problems. A new mutation operator is also described for this AIS. Fuzzy sets are used to model processing times and due dates. The objectives are to minimize the average tardiness and the number of tardy jobs. The developed new AIS algorithm is tested on real world data collected at an engine cylinder liner manufacturing process. The feasibility and effectiveness of the proposed AIS is demonstrated by comparing it with genetic algorithms. Computational results demonstrate that the proposed AIS algorithm is more effective meta-heuristic for multi objective flow shop scheduling problems with fuzzy processing time and due date.

Discrete particle swarm optimization to solve multi-objective limited-wait hybrid flow shop scheduling problem

Science.gov (United States)

Santosa, B.; Siswanto, N.; Fiqihesa

2018-04-01

This paper proposes a discrete Particle Swam Optimization (PSO) to solve limited-wait hybrid flowshop scheduing problem with multi objectives. Flow shop schedulimg represents the condition when several machines are arranged in series and each job must be processed at each machine with same sequence. The objective functions are minimizing completion time (makespan), total tardiness time, and total machine idle time. Flow shop scheduling model always grows to cope with the real production system accurately. Since flow shop scheduling is a NP-Hard problem then the most suitable method to solve is metaheuristics. One of metaheuristics algorithm is Particle Swarm Optimization (PSO), an algorithm which is based on the behavior of a swarm. Originally, PSO was intended to solve continuous optimization problems. Since flow shop scheduling is a discrete optimization problem, then, we need to modify PSO to fit the problem. The modification is done by using probability transition matrix mechanism. While to handle multi objectives problem, we use Pareto Optimal (MPSO). The results of MPSO is better than the PSO because the MPSO solution set produced higher probability to find the optimal solution. Besides the MPSO solution set is closer to the optimal solution

An economic lot and delivery scheduling problem with the fuzzy shelf life in a flexible job shop with unrelated parallel machines

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S. Dousthaghi

2012-08-01

Full Text Available This paper considers an economic lot and delivery scheduling problem (ELDSP in a fuzzy environment with the fuzzy shelf life for each product. This problem is formulated in a flexible job shop with unrelated parallel machines, when the planning horizon is finite and it determines lot sizing, scheduling and sequencing, simultaneously. The proposed model of this paper is based on the basic period (BP approach. In this paper, a mixed-integer nonlinear programming (MINLP model is presented and then it is changed into two models in the fuzzy shelf life. The main model is dependent to the multiple basic periods and it is difficult to solve the resulted proposed model for large-scale problems in reasonable amount of time; thus, an efficient heuristic method is proposed to solve the problem. The performance of the proposed model is demonstrated using some numerical examples.

Applicability aspects of workload control in job shop production

NARCIS (Netherlands)

Henrich, P.

2005-01-01

The term Job Shop Production (JSP) describes a manufacturing environment that produces piece goods in small batches. It is a common manufacturing environment in small and medium-sized enterprises (SMEs). The incoming orders often differ in the number of ordered products, their design, process

Minimizing makespan in a two-stage flow shop with parallel batch-processing machines and re-entrant jobs

Science.gov (United States)

Huang, J. D.; Liu, J. J.; Chen, Q. X.; Mao, N.

2017-06-01

Against a background of heat-treatment operations in mould manufacturing, a two-stage flow-shop scheduling problem is described for minimizing makespan with parallel batch-processing machines and re-entrant jobs. The weights and release dates of jobs are non-identical, but job processing times are equal. A mixed-integer linear programming model is developed and tested with small-scale scenarios. Given that the problem is NP hard, three heuristic construction methods with polynomial complexity are proposed. The worst case of the new constructive heuristic is analysed in detail. A method for computing lower bounds is proposed to test heuristic performance. Heuristic efficiency is tested with sets of scenarios. Compared with the two improved heuristics, the performance of the new constructive heuristic is superior.

A Local Search Algorithm for the Flow Shop Scheduling Problem with Release Dates

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Tao Ren

2015-01-01

Full Text Available This paper discusses the flow shop scheduling problem to minimize the makespan with release dates. By resequencing the jobs, a modified heuristic algorithm is obtained for handling large-sized problems. Moreover, based on some properties, a local search scheme is provided to improve the heuristic to gain high-quality solution for moderate-sized problems. A sequence-independent lower bound is presented to evaluate the performance of the algorithms. A series of simulation results demonstrate the effectiveness of the proposed algorithms.

Job shop scheduling model for non-identic machine with fixed delivery time to minimize tardiness

Science.gov (United States)

Kusuma, K. K.; Maruf, A.

2016-02-01

Scheduling non-identic machines problem with low utilization characteristic and fixed delivery time are frequent in manufacture industry. This paper propose a mathematical model to minimize total tardiness for non-identic machines in job shop environment. This model will be categorized as an integer linier programming model and using branch and bound algorithm as the solver method. We will use fixed delivery time as main constraint and different processing time to process a job. The result of this proposed model shows that the utilization of production machines can be increase with minimal tardiness using fixed delivery time as constraint.

COMPARISON BETWEEN MIXED INTEGER PROGRAMMING WITH HEURISTIC METHOD FOR JOB SHOP SCHEDULING WITH SEPARABLE SEQUENCE-DEPENDENT SETUPS

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I Gede Agus Widyadana

2001-01-01

Full Text Available The decisions to choose appropriate tools for solving industrial problems are not just tools that achieve optimal solution only but it should consider computation time too. One of industrial problems that still difficult to achieve both criteria is scheduling problem. This paper discuss comparison between mixed integer programming which result optimal solution and heuristic method to solve job shop scheduling problem with separable sequence-dependent setup. The problems are generated and the result shows that the heuristic methods still cannot satisfy optimal solution.

It's a Mall, Mall, Mall, Mall World: Jobs in Shopping Malls.

Science.gov (United States)

Green, Kathleen

1996-01-01

Provides information about a variety of nonsales jobs available in shopping malls: mall management, customer service, marketing, operations, security, maintenance, and administration. Includes information about educational requirements. (JOW)

Optimasi Penjadwalan Pengerjaan Software Pada Software House Dengan Flow-Shop Problem Menggunakan Artificial Bee Colony

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Muhammad Fhadli

2016-12-01

This research proposed an implementation related to software execution scheduling process at a software house with Flow-Shop Problem (FSP using Artificial Bee Colony (ABC algorithm. Which in FSP required a solution to complete some job/task along with its overall cost at a minimum. There is a constraint that should be kept to note in this research, that is the uncertainty completion time of its jobs. In this research, we will present a solution that is a sequence order of project execution with its overall completion time at a minimum. An experiment will be performed with 3 attempts on each experiment conditions, that is an experiment of iteration parameter and experiment of limit parameter. From this experiment, we concluded that the use of this algorithm explained in this paper can reduce project execution time if we increase the value of total iteration and total colony. Keywords: optimization, flow-shop problem, artificial bee colony, swarm intelligence, meta-heuristic.

Minimizing total weighted completion time in a proportionate flow shop

NARCIS (Netherlands)

Shakhlevich, N.V.; Hoogeveen, J.A.; Pinedo, M.L.

1998-01-01

We study the special case of the m machine flow shop problem in which the processing time of each operation of job j is equal to pj; this variant of the flow shop problem is known as the proportionate flow shop problem. We show that for any number of machines and for any regular performance

UN ALGORITMO GENÉTICO HÍBRIDO Y UN ENFRIAMIENTO SIMULADO PARA SOLUCIONAR EL PROBLEMA DE PROGRAMACIÓN DE PEDIDOS JOB SHOP UM ALGORITMO GENÉTICO HÍBRIDO E UM ESFRIAMENTO SIMULADO PARA SOLUCIONAR O PROBLEMA DE PROGRAMAÇÃO DE PEDIDOS JOB SHOP A HYBRID GENETIC ALGORITHM AND A SIMULATED ANNEALING FOR SOLVING THE JOB SHOP SCHEDULING PROBLEM

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José David Meisel

2010-07-01

mostraram que os algoritmos propostos arrojam bons resultados, com desvios ao redor dos melhores valores achados que não superam 5 % para os problemas mais complexos.Job Shop Scheduling Problem (JSP, classified as NP-Hard, has been a challenge for the scientific community because achieving an optimal solution to this problem is complicated as it grows in number of machines and jobs. Numerous techniques, including metaheuristics, have been used for its solution; however, the efficiency of the techniques, in terms of computational time, has not been very satisfactory. Because of this and for contributing to the solution of this problem, a simulated annealing (SA and an improved genetic algorithm (IGA have been proposed. The latter, by implementing a strategy of simulated annealing in the mutation phase, allows the algorithm to enhance and diversify the solutions at the same time, in order not to converge prematurely to a local optimum. The results showed that the proposed algorithms yield good results with deviations around the best values found not exceeding 5 % for more complex problems.

Improved teaching-learning-based and JAYA optimization algorithms for solving flexible flow shop scheduling problems

Science.gov (United States)

Buddala, Raviteja; Mahapatra, Siba Sankar

2017-11-01

Flexible flow shop (or a hybrid flow shop) scheduling problem is an extension of classical flow shop scheduling problem. In a simple flow shop configuration, a job having `g' operations is performed on `g' operation centres (stages) with each stage having only one machine. If any stage contains more than one machine for providing alternate processing facility, then the problem becomes a flexible flow shop problem (FFSP). FFSP which contains all the complexities involved in a simple flow shop and parallel machine scheduling problems is a well-known NP-hard (Non-deterministic polynomial time) problem. Owing to high computational complexity involved in solving these problems, it is not always possible to obtain an optimal solution in a reasonable computation time. To obtain near-optimal solutions in a reasonable computation time, a large variety of meta-heuristics have been proposed in the past. However, tuning algorithm-specific parameters for solving FFSP is rather tricky and time consuming. To address this limitation, teaching-learning-based optimization (TLBO) and JAYA algorithm are chosen for the study because these are not only recent meta-heuristics but they do not require tuning of algorithm-specific parameters. Although these algorithms seem to be elegant, they lose solution diversity after few iterations and get trapped at the local optima. To alleviate such drawback, a new local search procedure is proposed in this paper to improve the solution quality. Further, mutation strategy (inspired from genetic algorithm) is incorporated in the basic algorithm to maintain solution diversity in the population. Computational experiments have been conducted on standard benchmark problems to calculate makespan and computational time. It is found that the rate of convergence of TLBO is superior to JAYA. From the results, it is found that TLBO and JAYA outperform many algorithms reported in the literature and can be treated as efficient methods for solving the FFSP.

A Bee Evolutionary Guiding Nondominated Sorting Genetic Algorithm II for Multiobjective Flexible Job-Shop Scheduling

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Qianwang Deng

2017-01-01

Full Text Available Flexible job-shop scheduling problem (FJSP is an NP-hard puzzle which inherits the job-shop scheduling problem (JSP characteristics. This paper presents a bee evolutionary guiding nondominated sorting genetic algorithm II (BEG-NSGA-II for multiobjective FJSP (MO-FJSP with the objectives to minimize the maximal completion time, the workload of the most loaded machine, and the total workload of all machines. It adopts a two-stage optimization mechanism during the optimizing process. In the first stage, the NSGA-II algorithm with T iteration times is first used to obtain the initial population N, in which a bee evolutionary guiding scheme is presented to exploit the solution space extensively. In the second stage, the NSGA-II algorithm with GEN iteration times is used again to obtain the Pareto-optimal solutions. In order to enhance the searching ability and avoid the premature convergence, an updating mechanism is employed in this stage. More specifically, its population consists of three parts, and each of them changes with the iteration times. What is more, numerical simulations are carried out which are based on some published benchmark instances. Finally, the effectiveness of the proposed BEG-NSGA-II algorithm is shown by comparing the experimental results and the results of some well-known algorithms already existed.

A Bee Evolutionary Guiding Nondominated Sorting Genetic Algorithm II for Multiobjective Flexible Job-Shop Scheduling.

Science.gov (United States)

Deng, Qianwang; Gong, Guiliang; Gong, Xuran; Zhang, Like; Liu, Wei; Ren, Qinghua

2017-01-01

Flexible job-shop scheduling problem (FJSP) is an NP-hard puzzle which inherits the job-shop scheduling problem (JSP) characteristics. This paper presents a bee evolutionary guiding nondominated sorting genetic algorithm II (BEG-NSGA-II) for multiobjective FJSP (MO-FJSP) with the objectives to minimize the maximal completion time, the workload of the most loaded machine, and the total workload of all machines. It adopts a two-stage optimization mechanism during the optimizing process. In the first stage, the NSGA-II algorithm with T iteration times is first used to obtain the initial population N , in which a bee evolutionary guiding scheme is presented to exploit the solution space extensively. In the second stage, the NSGA-II algorithm with GEN iteration times is used again to obtain the Pareto-optimal solutions. In order to enhance the searching ability and avoid the premature convergence, an updating mechanism is employed in this stage. More specifically, its population consists of three parts, and each of them changes with the iteration times. What is more, numerical simulations are carried out which are based on some published benchmark instances. Finally, the effectiveness of the proposed BEG-NSGA-II algorithm is shown by comparing the experimental results and the results of some well-known algorithms already existed.

Flexible job-shop scheduling based on genetic algorithm and simulation validation

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Zhou Erming

2017-01-01

Full Text Available This paper selects flexible job-shop scheduling problem as the research object, and Constructs mathematical model aimed at minimizing the maximum makespan. Taking the transmission reverse gear production line of a transmission corporation as an example, genetic algorithm is applied for flexible jobshop scheduling problem to get the specific optimal scheduling results with MATLAB. DELMIA/QUEST based on 3D discrete event simulation is applied to construct the physical model of the production workshop. On the basis of the optimal scheduling results, the logical link of the physical model for the production workshop is established, besides, importing the appropriate process parameters to make virtual simulation on the production workshop. Finally, through analyzing the simulated results, it shows that the scheduling results are effective and reasonable.

Due date assignment procedures with dynamically updated coefficients for multi-level assembly job shops

NARCIS (Netherlands)

Adam, N.R.; Bertrand, J.W.M.; Morehead, D.C.; Surkis, J.

1993-01-01

This paper presents a study of due date assignment procedures in job shop environments where multi-level assembly jobs are processed and due dates are internally assigned. Most of the reported studies in the literature have focused on string type jobs. We propose a dynamic update approach (which

DESIGN OF A HYPERHEURISTIC FOR PRODUCTION SCHEDULING IN JOB SHOP ENVIRONMENTS DISEÑO DE UNA HIPERHEURISTICA PARA LA PROGRAMACION DE LA PRODUCCIÓN EN AMBIENTES JOB SHOP

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Omar Danilo Castrillón

2010-08-01

Full Text Available The objective of the present work is to diminish the total process time (Makespan and to increase the machine process time, by diminishing the idle time in a job-shop environment. Through the design of a hyper-heuristic based on an ant colony and genetic algorithms. This work is developed in two phases: in the first phase, a hyper-heuristic identification and definition is carried out for sequencing processes in job shop environments. In the second phase, the system effectiveness in the traditional production programming is shown. In the investigation project, an enterprise from the metal mechanic sector was chosen, where by means of a combination of an ant colony and genetic algorithms, the optimal route for an order is scheduled, achieving the optimization or suboptimization of its respective total process time in an upper percentage of 95%.El objetivo del presente trabajo es disminuir el tiempo de proceso (Makespan e incrementar el tiempo de trabajo de las maquinas, diminuyendo el tiempo de ocio en ambientes de Job Shop, a través del diseño de una Hiper-heurística basada en colonia de hormigas y algoritmos genéticos. Este trabajo se desarrolla en dos etapas: en la primera se realiza la definición e identificación de una Hiper-heurística para la secuenciación de procesos en ambientes Job shop. En la segunda etapa, es mostrada la efectividad del sistema en la programación de la producción. En el proyecto de investigación, se seleccionó una empresa del sector metalmecánico, donde por medio de una combinación de colonia de hormigas y algoritmos genéticos, se programa la ruta óptima para un pedido, logrando la optimización o suboptimización de su respectivo tiempo total de proceso en un porcentaje superior al 95%.

Avaliação de regras de sequenciamento da produção em ambientes Job shop e Flow shop por meio de simulação computacional

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Edna Barbosa da Silva

2012-01-01

Full Text Available In this work, the computational simulation is employed to study the effects of production sequencing rules in the performance of Job shop and Flow shop manufacturing environments. Eight sequencing rules were considered: SIPT (Shortest Imminent Processing Time, EDD (Earliest Due Date, DLS (Dynamic Least Slack, LWQ (Least Work in next Queue, FIFO (First In First Out, LIFO (Last In Last Out, CR (Critical Ratio and LS (Least Slack. These different sequencing rules were evaluated in relation to the makespan, total tardiness and number of tardy jobs, considering an experimental scenario which includes two configurations with eight machines (processes and ten different types of orders. A simulation model was developed with Arena software, incorporating randomness of order arrivals and the production times in such environments. The results show that the EDD and SIPT rules presented the best performances in the Job shop and in the Flow shop environments, respectively.

Worker flexibility in a parallel dual resource constrained job shop

NARCIS (Netherlands)

Yue, H.; Slomp, J.; Molleman, E.; van der Zee, D.J.

2008-01-01

In this paper we investigate cross-training policies in a dual resource constraint (DRC) parallel job shop where new part types are frequently introduced into the system. Each new part type introduction induces the need for workers to go through a learning curve. A cross-training policy relates to

Flow-shop scheduling problem under uncertainties: Review and trends

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Eliana María González-Neira

2017-03-01

Full Text Available Among the different tasks in production logistics, job scheduling is one of the most important at the operational decision-making level to enable organizations to achieve competiveness. Scheduling consists in the allocation of limited resources to activities over time in order to achieve one or more optimization objectives. Flow-shop (FS scheduling problems encompass the sequencing processes in environments in which the activities or operations are performed in a serial flow. This type of configuration includes assembly lines and the chemical, electronic, food, and metallurgical industries, among others. Scheduling has been mostly investigated for the deterministic cases, in which all parameters are known in advance and do not vary over time. Nevertheless, in real-world situations, events are frequently subject to uncertainties that can affect the decision-making process. Thus, it is important to study scheduling and sequencing activities under uncertainties since they can cause infeasibilities and disturbances. The purpose of this paper is to provide a general overview of the FS scheduling problem under uncertainties and its role in production logistics and to draw up opportunities for further research. To this end, 100 papers about FS and flexible flow-shop scheduling problems published from 2001 to October 2016 were analyzed and classified. Trends in the reviewed literature are presented and finally some research opportunities in the field are proposed.

A Hyper-Heuristic Ensemble Method for Static Job-Shop Scheduling.

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Hart, Emma; Sim, Kevin

2016-01-01

We describe a new hyper-heuristic method NELLI-GP for solving job-shop scheduling problems (JSSP) that evolves an ensemble of heuristics. The ensemble adopts a divide-and-conquer approach in which each heuristic solves a unique subset of the instance set considered. NELLI-GP extends an existing ensemble method called NELLI by introducing a novel heuristic generator that evolves heuristics composed of linear sequences of dispatching rules: each rule is represented using a tree structure and is itself evolved. Following a training period, the ensemble is shown to outperform both existing dispatching rules and a standard genetic programming algorithm on a large set of new test instances. In addition, it obtains superior results on a set of 210 benchmark problems from the literature when compared to two state-of-the-art hyper-heuristic approaches. Further analysis of the relationship between heuristics in the evolved ensemble and the instances each solves provides new insights into features that might describe similar instances.

Prevalence of job strain among Indian foundry shop floor workers.

Science.gov (United States)

Mohan, G Madhan; Elangovan, S; Prasad, P S S; Krishna, P Rama; Mokkapati, Anil Kumar

2008-01-01

Global competition in manufacturing sector demand higher productivity levels. In this context, workers in this sector are set with high output targets, leading to job strain. In addition to the strain, hazardous conditions also prevail in some of the manufacturing processes like foundry activities. This paper attempts to appraise the prevalence of job strain among foundry shop floor workers in India with the help of Demands-Control model [8]. In this study, data was collected through a survey using 49-item Job Content Questionnaire (JCQ) [9], a widely used and well-validated test for job strain. Then the data was subjected to statistical analysis after ascertaining the reliability. This survey has revealed that 25% of workers in foundry were experiencing high job strain. Hazardous working conditions, limited decision making authority, etc. appear to be the main contributing factors for the higher levels of strain.

Shopping for Jobs: Mall Internship Program Opens Doors for HVAC Students.

Science.gov (United States)

Nolot, Terry

1995-01-01

Ivy Tech State College uses River Falls, a shopping mall, as an enormous heating, ventilation, and air conditioning laboratory. Students spend Saturdays working with full-time technicians getting invaluable training and experience. Students see the program as a professional opportunity and a direct route to jobs. (JOW)

ARTIFICIAL INTELLIGENCE EFFECTIVENESS IN JOB SHOP ENVIRONMENTS

OpenAIRE

OMAR CASTRILLON; WILLIAM SARACHE; JAIME GIRALDO

2011-01-01

El objetivo del presente trabajo, es definir una nueva metodología la cual permita comparar la efectividad de algunas de las principales técnicas de inteligencia artificial (aleatorias, búsqueda tabú, minería de datos, algoritmos evolutivos). Esta metodología es aplicada en los procesos de secuenciación de la producción en ambientes job shop, en un problema con N pedidos y M máquinas, donde cada uno de los pedidos debe pasar por todas las máquinas sin importar el orden. Estas técnicas son med...

Comparative study of heuristics algorithms in solving flexible job shop scheduling problem with condition based maintenance

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Yahong Zheng

2014-05-01

Full Text Available Purpose: This paper focuses on a classic optimization problem in operations research, the flexible job shop scheduling problem (FJSP, to discuss the method to deal with uncertainty in a manufacturing system.Design/methodology/approach: In this paper, condition based maintenance (CBM, a kind of preventive maintenance, is suggested to reduce unavailability of machines. Different to the simultaneous scheduling algorithm (SSA used in the previous article (Neale & Cameron,1979, an inserting algorithm (IA is applied, in which firstly a pre-schedule is obtained through heuristic algorithm and then maintenance tasks are inserted into the pre-schedule scheme.Findings: It is encouraging that a new better solution for an instance in benchmark of FJSP is obtained in this research. Moreover, factually SSA used in literature for solving normal FJSPPM (FJSP with PM is not suitable for the dynamic FJSPPM. Through application in the benchmark of normal FJSPPM, it is found that although IA obtains inferior results compared to SSA used in literature, it performs much better in executing speed.Originality/value: Different to traditional scheduling of FJSP, uncertainty of machines is taken into account, which increases the complexity of the problem. An inserting algorithm (IA is proposed to solve the dynamic scheduling problem. It is stated that the quality of the final result depends much on the quality of the pre-schedule obtained during the procedure of solving a normal FJSP. In order to find the best solution of FJSP, a comparative study of three heuristics is carried out, the integrated GA, ACO and ABC. In the comparative study, we find that GA performs best in the three heuristic algorithms. Meanwhile, a new better solution for an instance in benchmark of FJSP is obtained in this research.

Moving from job-shop to production cells without losing flexibility: a case study from the wooden frames industry

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Dinis-Carvalho, J.

2014-11-01

Full Text Available Cellular production is usually seen as a hybrid approach between job-shop and flow-line paradigms, reducing the major disadvantages of these two paradigms: the low productivity of job-shops and the low flexibility (in terms of products’ variety of the flow-lines. This paper describes the implementation of a production cell in a production unit of wood- framed pictures and mirrors, which was originally configured as a traditional job-shop, without losing the necessary flexibility to face market demand and simultaneously increasing the production unit’s performance. By implementing a highly flexible cell, very significant improvements were expected for the system’s overall performance and the quality of the products. These expectations were met, and the implementation was successful, as demonstrated by the results presented.

Due Date Assignment in a Dynamic Job Shop with the Orthogonal Kernel Least Squares Algorithm

Science.gov (United States)

Yang, D. H.; Hu, L.; Qian, Y.

2017-06-01

Meeting due dates is a key goal in the manufacturing industries. This paper proposes a method for due date assignment (DDA) by using the Orthogonal Kernel Least Squares Algorithm (OKLSA). A simulation model is built to imitate the production process of a highly dynamic job shop. Several factors describing job characteristics and system state are extracted as attributes to predict job flow-times. A number of experiments under conditions of varying dispatching rules and 90% shop utilization level have been carried out to evaluate the effectiveness of OKLSA applied for DDA. The prediction performance of OKLSA is compared with those of five conventional DDA models and back-propagation neural network (BPNN). The experimental results indicate that OKLSA is statistically superior to other DDA models in terms of mean absolute lateness and root mean squares lateness in most cases. The only exception occurs when the shortest processing time rule is used for dispatching jobs, the difference between OKLSA and BPNN is not statistically significant.

A Markov chain analysis of the effectiveness of drum-buffer-rope material flow management in job shop environment

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Masoud Rabbani

2015-09-01

Full Text Available The theory of constraints is an approach for production planning and control, which emphasizes on the constraints in the system to increase throughput. The theory of constraints is often referred to as Drum-Buffer-Rope developed originally by Goldratt. Drum-Buffer-Rope uses the drum or constraint to create a schedule based on the finite capacity of the first bottleneck. Because of complexity of the job shop environment, Drum-Buffer-Rope material flow management has very little attention to job shop environment. The objective of this paper is to apply the Drum-Buffer-Rope technique in the job shop environment using a Markov chain analysis to compare traditional method with Drum-Buffer-Rope. Four measurement parameters were considered and the result showed the advantage of Drum-Buffer-Rope approach compared with traditional one.

A Hybrid Metaheuristic Approach for Minimizing the Total Flow Time in A Flow Shop Sequence Dependent Group Scheduling Problem

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Antonio Costa

2014-07-01

Full Text Available Production processes in Cellular Manufacturing Systems (CMS often involve groups of parts sharing the same technological requirements in terms of tooling and setup. The issue of scheduling such parts through a flow-shop production layout is known as the Flow-Shop Group Scheduling (FSGS problem or, whether setup times are sequence-dependent, the Flow-Shop Sequence-Dependent Group Scheduling (FSDGS problem. This paper addresses the FSDGS issue, proposing a hybrid metaheuristic procedure integrating features from Genetic Algorithms (GAs and Biased Random Sampling (BRS search techniques with the aim of minimizing the total flow time, i.e., the sum of completion times of all jobs. A well-known benchmark of test cases, entailing problems with two, three, and six machines, is employed for both tuning the relevant parameters of the developed procedure and assessing its performances against two metaheuristic algorithms recently presented by literature. The obtained results and a properly arranged ANOVA analysis highlight the superiority of the proposed approach in tackling the scheduling problem under investigation.

Integrating make-to-order and make-to-stock in job shop control (Reprint of International Journal of Production Economics 185, pp 1-10)

NARCIS (Netherlands)

Beemsterboer, Bart; Land, Martin; Teunter, Ruud; Bokhorst, Jos

2017-01-01

Demand fluctuations in make-to-order job shops lead to utilisation fluctuations and delivery delays, particularly in periods with high demand. Many job shop production companies therefore include some standardised products in their product mix and use a hybrid make-to-order/make-to-stock production

Optimising Job-Shop Functions Utilising the Score-Function Method

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2000-01-01

During the last 1-2 decades, simulation optimisation of discrete event dynamic systems (DEDS) has made considerable theoretical progress with respect to computational efficiency. The score-function (SF) method and the infinitesimal perturbation analysis (IPA) are two candidates belonging to this ......During the last 1-2 decades, simulation optimisation of discrete event dynamic systems (DEDS) has made considerable theoretical progress with respect to computational efficiency. The score-function (SF) method and the infinitesimal perturbation analysis (IPA) are two candidates belonging...... of a Job-Shop can be handled by the SF method....

Evaluation and Selection of Best Priority Sequencing Rule in Job Shop Scheduling using Hybrid MCDM Technique

Science.gov (United States)

Kiran Kumar, Kalla; Nagaraju, Dega; Gayathri, S.; Narayanan, S.

2017-05-01

Priority Sequencing Rules provide the guidance for the order in which the jobs are to be processed at a workstation. The application of different priority rules in job shop scheduling gives different order of scheduling. More experimentation needs to be conducted before a final choice is made to know the best priority sequencing rule. Hence, a comprehensive method of selecting the right choice is essential in managerial decision making perspective. This paper considers seven different priority sequencing rules in job shop scheduling. For evaluation and selection of the best priority sequencing rule, a set of eight criteria are considered. The aim of this work is to demonstrate the methodology of evaluating and selecting the best priority sequencing rule by using hybrid multi criteria decision making technique (MCDM), i.e., analytical hierarchy process (AHP) with technique for order preference by similarity to ideal solution (TOPSIS). The criteria weights are calculated by using AHP whereas the relative closeness values of all priority sequencing rules are computed based on TOPSIS with the help of data acquired from the shop floor of a manufacturing firm. Finally, from the findings of this work, the priority sequencing rules are ranked from most important to least important. The comprehensive methodology presented in this paper is very much essential for the management of a workstation to choose the best priority sequencing rule among the available alternatives for processing the jobs with maximum benefit.

Genetic Algorithm Combined with Gradient Information for Flexible Job-shop Scheduling Problem with Different Varieties and Small Batches

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Chen Ming

2017-01-01

Full Text Available To solve the Flexible Job-shop Scheduling Problem (FJSP with different varieties and small batches, a modified meta-heuristic algorithm based on Genetic Algorithm (GA is proposed in which gene encoding is divided into process encoding and machine encoding, and according to the encoding mode, the machine gene fragment is connected with the process gene fragment and can be changed with the alteration of process genes. In order to get the global optimal solutions, the crossover and mutation operation of the process gene fragment and machine gene fragment are carried out respectively. In the initialization operation, the machines with shorter manufacturing time are more likely to be chosen to accelerate the convergence speed and then the tournament selection strategy is applied due to the minimum optimization objective. Meanwhile, a judgment condition of the crossover point quantity is introduced to speed up the population evolution and as an important interaction bridge between the current machine and alternative machines in the incidence matrix, a novel mutation operation of machine genes is proposed to achieve the replacement of manufacturing machines. The benchmark test shows the correctness of proposed algorithm and the case simulation proves the proposed algorithm has better performance compared with existing algorithms.

Production Scheduling in Complex Job Shops from an Industrie 4.0 Perspective: A Review and Challenges in the Semiconductor Industry

OpenAIRE

Waschneck, Bernd; Bauernhansl, Thomas; Altenmüller, Thomas; Kyek, Andreas

2017-01-01

On the one hand, Industrie 4.0 has recently emerged as the keyword for increasing productivity in the 21st century. On the other hand, production scheduling in a Complex Job Shop (CJS) environment, such as wafer fabrication facilities, has drawn interest of researchers dating back to the 1950s [65, 18]. Although both research areas overlap, there seems to be very little interchange of ideas. This review presents and assesses production scheduling techniques in complex job shops from an Indust...

A synergetic combination of small and large neighborhood schemes in developing an effective procedure for solving the job shop scheduling problem.

Science.gov (United States)

Amirghasemi, Mehrdad; Zamani, Reza

2014-01-01

This paper presents an effective procedure for solving the job shop problem. Synergistically combining small and large neighborhood schemes, the procedure consists of four components, namely (i) a construction method for generating semi-active schedules by a forward-backward mechanism, (ii) a local search for manipulating a small neighborhood structure guided by a tabu list, (iii) a feedback-based mechanism for perturbing the solutions generated, and (iv) a very large-neighborhood local search guided by a forward-backward shifting bottleneck method. The combination of shifting bottleneck mechanism and tabu list is used as a means of the manipulation of neighborhood structures, and the perturbation mechanism employed diversifies the search. A feedback mechanism, called repeat-check, detects consequent repeats and ignites a perturbation when the total number of consecutive repeats for two identical makespan values reaches a given threshold. The results of extensive computational experiments on the benchmark instances indicate that the combination of these four components is synergetic, in the sense that they collectively make the procedure fast and robust.

Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

Energy Technology Data Exchange (ETDEWEB)

Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

2017-07-01

Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

International Nuclear Information System (INIS)

Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

2017-01-01

Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

Efficient bounding schemes for the two-center hybrid flow shop scheduling problem with removal times.

Science.gov (United States)

Hidri, Lotfi; Gharbi, Anis; Louly, Mohamed Aly

2014-01-01

We focus on the two-center hybrid flow shop scheduling problem with identical parallel machines and removal times. The job removal time is the required duration to remove it from a machine after its processing. The objective is to minimize the maximum completion time (makespan). A heuristic and a lower bound are proposed for this NP-Hard problem. These procedures are based on the optimal solution of the parallel machine scheduling problem with release dates and delivery times. The heuristic is composed of two phases. The first one is a constructive phase in which an initial feasible solution is provided, while the second phase is an improvement one. Intensive computational experiments have been conducted to confirm the good performance of the proposed procedures.

Design and simulation of CONWIP in the complex flexible job shop of a Make-To-Order manufacturing firm ,

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Giovanni Romagnoli

2015-01-01

Full Text Available This paper presents a methodology for the design and integration of CONWIP in a make-to-order firm. The approach proposed was applied directly to the flexible job shop of a real manufacturing firm in order to assess the validity of the methodology. After the description of the whole plant layout, attention was focused on a section of the shop floor (21 workstations. The CONWIP system deals with multiple-product families and is characterized by path-type cards and a pull-from-the-bottleneck scheme. The cards release strategy and a customized dispatching rule were created to meet the firm’s specific needs. After the simulation model of the present state was built and validated, the future state to be implemented was created and simulated (i.e. the CONWIP system. The comparison between the two systems achieved excellent results, and showed that CONWIP is a very interesting tool for planning and controlling a complex flexible job shop.

Cobacabana (control of balance by card-based navigation) : A card-based system for job shop control

NARCIS (Netherlands)

Land, M.J.

Existing card-based production control systems such as Kanban are mostly dedicated to repetitive production environments. Cards-based systems for job shop control are lacking, while particularly this industry segment shows a need for simple control systems. This paper aims at filling the gap by

Flexible Job-Shop Scheduling with Dual-Resource Constraints to Minimize Tardiness Using Genetic Algorithm

Science.gov (United States)

Paksi, A. B. N.; Ma'ruf, A.

2016-02-01

In general, both machines and human resources are needed for processing a job on production floor. However, most classical scheduling problems have ignored the possible constraint caused by availability of workers and have considered only machines as a limited resource. In addition, along with production technology development, routing flexibility appears as a consequence of high product variety and medium demand for each product. Routing flexibility is caused by capability of machines that offers more than one machining process. This paper presents a method to address scheduling problem constrained by both machines and workers, considering routing flexibility. Scheduling in a Dual-Resource Constrained shop is categorized as NP-hard problem that needs long computational time. Meta-heuristic approach, based on Genetic Algorithm, is used due to its practical implementation in industry. Developed Genetic Algorithm uses indirect chromosome representative and procedure to transform chromosome into Gantt chart. Genetic operators, namely selection, elitism, crossover, and mutation are developed to search the best fitness value until steady state condition is achieved. A case study in a manufacturing SME is used to minimize tardiness as objective function. The algorithm has shown 25.6% reduction of tardiness, equal to 43.5 hours.

A Local and Global Search Combine Particle Swarm Optimization Algorithm for Job-Shop Scheduling to Minimize Makespan

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Zhigang Lian

2010-01-01

Full Text Available The Job-shop scheduling problem (JSSP is a branch of production scheduling, which is among the hardest combinatorial optimization problems. Many different approaches have been applied to optimize JSSP, but for some JSSP even with moderate size cannot be solved to guarantee optimality. The original particle swarm optimization algorithm (OPSOA, generally, is used to solve continuous problems, and rarely to optimize discrete problems such as JSSP. In OPSOA, through research I find that it has a tendency to get stuck in a near optimal solution especially for middle and large size problems. The local and global search combine particle swarm optimization algorithm (LGSCPSOA is used to solve JSSP, where particle-updating mechanism benefits from the searching experience of one particle itself, the best of all particles in the swarm, and the best of particles in neighborhood population. The new coding method is used in LGSCPSOA to optimize JSSP, and it gets all sequences are feasible solutions. Three representative instances are made computational experiment, and simulation shows that the LGSCPSOA is efficacious for JSSP to minimize makespan.

Literature Review on the Hybrid Flow Shop Scheduling Problem with Unrelated Parallel Machines

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Eliana Marcela Peña Tibaduiza

2017-01-01

Full Text Available Context: The flow shop hybrid problem with unrelated parallel machines has been less studied in the academia compared to the flow shop hybrid with identical processors. For this reason, there are few reports about the kind of application of this problem in industries. Method: A literature review of the state of the art on flow-shop scheduling problem was conducted by collecting and analyzing academic papers on several scientific databases. For this aim, a search query was constructed using keywords defining the problem and checking the inclusion of unrelated parallel machines in such definition; as a result, 50 papers were finally selected for this study. Results: A classification of the problem according to the characteristics of the production system was performed, also solution methods, constraints and objective functions commonly used are presented. Conclusions: An increasing trend is observed in studies of flow shop with multiple stages, but few are based on industry case-studies.

PERBANDINGAN KINERJA ALGORITMA GENETIKA DAN ALGORITMA HEURISTIK RAJENDRAN UNTUK PENJADUALAN PRODUKSI JENIS FLOW SHOP

Directory of Open Access Journals (Sweden)

Tessa Vanina Soetanto

1999-01-01

Full Text Available Flow shop scheduling problem is to schedule a production process of n jobs that go through the same process sequence and the same m machines. Most researches are don to accomplish only one objective, i.e. minimizing makespan. The other objective, such as total flow time, or multiple objectives that is minimizing makespan, total flow time and machine idle time, will be more effective in reducing scheduling cost, as written in French (1982. Rajendran algorithm (1995 that solves flow shop problem with multiple objectives will be used to evaluate the proposed algorithm: Genetic Algorithm, developed by Sridhar & Rajendran (1996 on a problem that existed in a shoe factory. Abstract in Bahasa Indonesia : Masalah penjadualan flow shop adalah menjadualkan proses produksi dari masing-masing n job yang mempunyai urutan proses produksi dan melalui m mesin yang sama. Kebanyakan penelitian hanya mengacu pada satu tujuan saja yaitu meminimumkan makespan. Tujuan yang lain, seperti meminimumkan total flow time atau multiple objectives yang meminimumkan makespan, total flow time dan machine idle time akan lebih efektif dalam mengurangi biaya penjadualan, sebagaimana dikatakan oleh French (1982. Algoritma Rajendran (1995 yang menyelesaikan masalah flow shop dengan multiple objectives akan dipergunakan untuk mengevaluasi algoritma usulan: Algoritma Genetika, yang dikembangkan oleh Sridhar & Rajendran (1996 pada suatu masalah yang ditemui di suatu perusahaan sepatu. Kata kunci: flow shop, algoritma genetika, multiple objectives

Marriage in Honey Bees Optimization Algorithm for Flow-shop Problems

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Pedro PALOMINOS

2012-01-01

Full Text Available The objective of this work is to make a comparative study of the Marriage in Honeybees Op-timization (MBO metaheuristic for flow-shop scheduling problems. This paper is focused on the design possibilities of the mating flight space shared by queens and drones. The proposed algorithm uses a 2-dimensional torus as an explicit mating space instead of the simulated an-nealing one in the original MBO. After testing different alternatives with benchmark datasets, the results show that the modeled and implemented metaheuristic is effective to solve flow-shop type problems, providing a new approach to solve other NP-Hard problems.

Discrete Bat Algorithm for Optimal Problem of Permutation Flow Shop Scheduling

Science.gov (United States)

Luo, Qifang; Zhou, Yongquan; Xie, Jian; Ma, Mingzhi; Li, Liangliang

2014-01-01

A discrete bat algorithm (DBA) is proposed for optimal permutation flow shop scheduling problem (PFSP). Firstly, the discrete bat algorithm is constructed based on the idea of basic bat algorithm, which divide whole scheduling problem into many subscheduling problems and then NEH heuristic be introduced to solve subscheduling problem. Secondly, some subsequences are operated with certain probability in the pulse emission and loudness phases. An intensive virtual population neighborhood search is integrated into the discrete bat algorithm to further improve the performance. Finally, the experimental results show the suitability and efficiency of the present discrete bat algorithm for optimal permutation flow shop scheduling problem. PMID:25243220

Discrete bat algorithm for optimal problem of permutation flow shop scheduling.

Science.gov (United States)

Luo, Qifang; Zhou, Yongquan; Xie, Jian; Ma, Mingzhi; Li, Liangliang

2014-01-01

A discrete bat algorithm (DBA) is proposed for optimal permutation flow shop scheduling problem (PFSP). Firstly, the discrete bat algorithm is constructed based on the idea of basic bat algorithm, which divide whole scheduling problem into many subscheduling problems and then NEH heuristic be introduced to solve subscheduling problem. Secondly, some subsequences are operated with certain probability in the pulse emission and loudness phases. An intensive virtual population neighborhood search is integrated into the discrete bat algorithm to further improve the performance. Finally, the experimental results show the suitability and efficiency of the present discrete bat algorithm for optimal permutation flow shop scheduling problem.

Minimizing the Makespan for a Two-Stage Three-Machine Assembly Flow Shop Problem with the Sum-of-Processing-Time Based Learning Effect

Directory of Open Access Journals (Sweden)

Win-Chin Lin

2018-01-01

Full Text Available Two-stage production process and its applications appear in many production environments. Job processing times are usually assumed to be constant throughout the process. In fact, the learning effect accrued from repetitive work experiences, which leads to the reduction of actual job processing times, indeed exists in many production environments. However, the issue of learning effect is rarely addressed in solving a two-stage assembly scheduling problem. Motivated by this observation, the author studies a two-stage three-machine assembly flow shop problem with a learning effect based on sum of the processing times of already processed jobs to minimize the makespan criterion. Because this problem is proved to be NP-hard, a branch-and-bound method embedded with some developed dominance propositions and a lower bound is employed to search for optimal solutions. A cloud theory-based simulated annealing (CSA algorithm and an iterated greedy (IG algorithm with four different local search methods are used to find near-optimal solutions for small and large number of jobs. The performances of adopted algorithms are subsequently compared through computational experiments and nonparametric statistical analyses, including the Kruskal–Wallis test and a multiple comparison procedure.

Review of job shop scheduling research and its new perspectives under Industry 4.0

OpenAIRE

Zhang, Jian; Ding, Guofu; Zou, Yisheng; Qin, Sheng-feng; Fu, Jianlin

2017-01-01

Traditional job shop scheduling is concentrated on centralized scheduling or semi-distributed scheduling. Under the Industry 4.0, the scheduling should deal with a smart and distributed manufacturing system supported by novel and emerging manufacturing technologies such as mass customization, Cyber-Physics Systems, Digital Twin, and SMAC (Social, Mobile, Analytics, Cloud). The scheduling research needs to shift its focus to smart distributed scheduling modeling and optimization. In order to t...

Revisiting the NEH algorithm- the power of job insertion technique for optimizing the makespan in permutation flow shop scheduling

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A. Baskar

2016-04-01

Full Text Available Permutation flow shop scheduling problems have been an interesting area of research for over six decades. Out of the several parameters, minimization of makespan has been studied much over the years. The problems are widely regarded as NP-Complete if the number of machines is more than three. As the computation time grows exponentially with respect to the problem size, heuristics and meta-heuristics have been proposed by many authors that give reasonably accurate and acceptable results. The NEH algorithm proposed in 1983 is still considered as one of the best simple, constructive heuristics for the minimization of makespan. This paper analyses the powerful job insertion technique used by NEH algorithm and proposes seven new variants, the complexity level remains same. 120 numbers of problem instances proposed by Taillard have been used for the purpose of validating the algorithms. Out of the seven, three produce better results than the original NEH algorithm.

FLOW-SHOP SCHEDULING WITH MULTIPLE OPERATIONS AND TIME LAGS

NARCIS (Netherlands)

RIEZEBOS, J; GAALMAN, GJC; GUPTA, JND

A scheduling system is proposed and developed for a special type of flow shop. Ln this flow shop there is one machine at each stage. A job may require multiple operations at each stage. The first operation of a job on stage j cannot start until the last operation of the job on stage j - 1 has

Do job demands and job control affect problem-solving?

Science.gov (United States)

Bergman, Peter N; Ahlberg, Gunnel; Johansson, Gun; Stoetzer, Ulrich; Aborg, Carl; Hallsten, Lennart; Lundberg, Ingvar

2012-01-01

The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.

ARTIFICIAL INTELLIGENCE EFFECTIVENESS IN JOB SHOP ENVIRONMENTS

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OMAR CASTRILLON

2011-01-01

Full Text Available El objetivo del presente trabajo, es definir una nueva metodología la cual permita comparar la efectividad de algunas de las principales técnicas de inteligencia artificial (aleatorias, búsqueda tabú, minería de datos, algoritmos evolutivos. Esta metodología es aplicada en los procesos de secuenciación de la producción en ambientes job shop, en un problema con N pedidos y M máquinas, donde cada uno de los pedidos debe pasar por todas las máquinas sin importar el orden. Estas técnicas son medidas en las variables tiempo total de proceso, tiempo total muerto y porcentaje de utilización de las máquinas. Inicialmente, una revisión teórica fue realizada, esta muestra la utilidad y efectividad de la inteligencia artificial en los procesos de secuenciación de la producción. Posteriormente y con base en la experimentación planteada, los resultados obtenidos, muestran que estas técnicas presentan una efectividad superior al 95%, con un intervalo de confiabilidad del 99.5% medido en las variables objeto de estudio.

Automatic programming via iterated local search for dynamic job shop scheduling.

Science.gov (United States)

Nguyen, Su; Zhang, Mengjie; Johnston, Mark; Tan, Kay Chen

2015-01-01

Dispatching rules have been commonly used in practice for making sequencing and scheduling decisions. Due to specific characteristics of each manufacturing system, there is no universal dispatching rule that can dominate in all situations. Therefore, it is important to design specialized dispatching rules to enhance the scheduling performance for each manufacturing environment. Evolutionary computation approaches such as tree-based genetic programming (TGP) and gene expression programming (GEP) have been proposed to facilitate the design task through automatic design of dispatching rules. However, these methods are still limited by their high computational cost and low exploitation ability. To overcome this problem, we develop a new approach to automatic programming via iterated local search (APRILS) for dynamic job shop scheduling. The key idea of APRILS is to perform multiple local searches started with programs modified from the best obtained programs so far. The experiments show that APRILS outperforms TGP and GEP in most simulation scenarios in terms of effectiveness and efficiency. The analysis also shows that programs generated by APRILS are more compact than those obtained by genetic programming. An investigation of the behavior of APRILS suggests that the good performance of APRILS comes from the balance between exploration and exploitation in its search mechanism.

Flow shop scheduling decisions through Techniques for Order Preference by Similarity to an Ideal Solution (TOPSIS

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Arun Gupta

2016-07-01

Full Text Available The flow-shop scheduling problem (FSP has been widely studied in the literature and having a very active research area. Over the last few decades, a number of heuristic/meta-heuristic solution techniques have been developed. Some of these techniques offer excellent effectiveness and efficiency at the expense of substantial implementation efforts and being extremely complicated. This paper brings out the application of a Multi-Criteria Decision Making (MCDM method known as techniques for order preference by similarity to an ideal solution (TOPSIS using different weighting schemes in flow-shop environment. The objective function is identification of a job sequence which in turn would have minimum makespan (total job completion time. The application of the proposed method to flow shop scheduling is presented and explained with a numerical example. The results of the proposed TOPSIS based technique of FSP are also compared on the basis of some benchmark problems and found compatible with the results obtained from other standard procedures.

A new Nawaz-Enscore-Ham-based heuristic for permutation flow-shop problems with bicriteria of makespan and machine idle time

Science.gov (United States)

Liu, Weibo; Jin, Yan; Price, Mark

2016-10-01

A new heuristic based on the Nawaz-Enscore-Ham algorithm is proposed in this article for solving a permutation flow-shop scheduling problem. A new priority rule is proposed by accounting for the average, mean absolute deviation, skewness and kurtosis, in order to fully describe the distribution style of processing times. A new tie-breaking rule is also introduced for achieving effective job insertion with the objective of minimizing both makespan and machine idle time. Statistical tests illustrate better solution quality of the proposed algorithm compared to existing benchmark heuristics.

On non-permutation solutions to some two machine flow shop scheduling problems

NARCIS (Netherlands)

V. Strusevich (Vitaly); P.J. Zwaneveld (Peter)

1994-01-01

textabstractIn this paper, we study two versions of the two machine flow shop scheduling problem, where schedule length is to be minimized. First, we consider the two machine flow shop with setup, processing, and removal times separated. It is shown that an optimal solution need not be a permutation

Handbook for Trade and Industrial Shop Teachers.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This handbook is intended to help teachers of pre-employment shop courses in organizing and delivering instruction in both the shop and classroom. Addressed in the guide are the following topics: the instructor's place in the local school organization; the instructor's job (objectives, advisory committees, occupational analysis, shop/classroom and…

Time complexity and linear-time approximation of the ancient two-machine flow shop

NARCIS (Netherlands)

Rote, G.; Woeginger, G.J.

1998-01-01

We consider the scheduling problems F2¿Cmax and F2|no-wait|Cmax, i.e. makespan minimization in a two-machine flow shop, with and without no wait in process. For both problems solution algorithms based on sorting with O(n log n) running time are known, where n denotes the number of jobs. [1, 2]. We

A Comparison of the DISASTER (Trademark) Scheduling Software with a Simultaneous Scheduling Algorithm for Minimizing Maximum Tardiness in Job Shops

Science.gov (United States)

1993-09-01

goal ( Heizer , Render , and Stair, 1993:94). Integer Prgronmming. Integer programming is a general purpose approach used to optimally solve job shop...Scheduling," Operations Research Journal. 29, No 4: 646-667 (July-August 1981). Heizer , Jay, Barry Render and Ralph M. Stair, Jr. Production and Operations

Outsourcing and scheduling for a two-machine flow shop with release times

Science.gov (United States)

Ahmadizar, Fardin; Amiri, Zeinab

2018-03-01

This article addresses a two-machine flow shop scheduling problem where jobs are released intermittently and outsourcing is allowed. The first operations of outsourced jobs are processed by the first subcontractor, they are transported in batches to the second subcontractor for processing their second operations, and finally they are transported back to the manufacturer. The objective is to select a subset of jobs to be outsourced, to schedule both the in-house and the outsourced jobs, and to determine a transportation plan for the outsourced jobs so as to minimize the sum of the makespan and the outsourcing and transportation costs. Two mathematical models of the problem and several necessary optimality conditions are presented. A solution approach is then proposed by incorporating the dominance properties with an ant colony algorithm. Finally, computational experiments are conducted to evaluate the performance of the models and solution approach.

A United Framework for Solving Multiagent Task Assignment Problems

National Research Council Canada - National Science Library

Cousin, Kevin

2007-01-01

.... The CMTS descriptor represents a wide range of classical and modern problems, such as job shop scheduling, the traveling salesman problem, vehicle routing, and cooperative multi-object tracking...

An extended continuous estimation of distribution algorithm for solving the permutation flow-shop scheduling problem

Science.gov (United States)

Shao, Zhongshi; Pi, Dechang; Shao, Weishi

2017-11-01

This article proposes an extended continuous estimation of distribution algorithm (ECEDA) to solve the permutation flow-shop scheduling problem (PFSP). In ECEDA, to make a continuous estimation of distribution algorithm (EDA) suitable for the PFSP, the largest order value rule is applied to convert continuous vectors to discrete job permutations. A probabilistic model based on a mixed Gaussian and Cauchy distribution is built to maintain the exploration ability of the EDA. Two effective local search methods, i.e. revolver-based variable neighbourhood search and Hénon chaotic-based local search, are designed and incorporated into the EDA to enhance the local exploitation. The parameters of the proposed ECEDA are calibrated by means of a design of experiments approach. Simulation results and comparisons based on some benchmark instances show the efficiency of the proposed algorithm for solving the PFSP.

MULTICRITERIA HYBRID FLOW SHOP SCHEDULING PROBLEM: LITERATURE REVIEW, ANALYSIS, AND FUTURE RESEARCH

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Marcia de Fatima Morais

2014-12-01

Full Text Available This research focuses on the Hybrid Flow Shop production scheduling problem, which is one of the most difficult problems to solve. The literature points to several studies that focus the Hybrid Flow Shop scheduling problem with monocriteria functions. Despite of the fact that, many real world problems involve several objective functions, they can often compete and conflict, leading researchers to concentrate direct their efforts on the development of methods that take consider this variant into consideration. The goal of the study is to review and analyze the methods in order to solve the Hybrid Flow Shop production scheduling problem with multicriteria functions in the literature. The analyses were performed using several papers that have been published over the years, also the parallel machines types, the approach used to develop solution methods, the type of method develop, the objective function, the performance criterion adopted, and the additional constraints considered. The results of the reviewing and analysis of 46 papers showed opportunities for future research on this topic, including the following: (i use uniform and dedicated parallel machines, (ii use exact and metaheuristics approaches, (iv develop lower and uppers bounds, relations of dominance and different search strategies to improve the computational time of the exact methods,  (v develop  other types of metaheuristic, (vi work with anticipatory setups, and (vii add constraints faced by the production systems itself.

Research on consumable distribution mode of shipbuilder’s shop based on vehicle routing problem

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Xiang Su

2017-02-01

Full Text Available A distribution vehicle optimization is established with considerations for the problem of long period of requisition and high shop costs due to the existing consumable requisition mode in shipbuilder’s shops for the requirements of shops for consumables. The shortest traveling distance of distribution vehicles are calculated with the genetic algorithm (GA. Explorations are made into a shop consumable distribution mode for shipbuilders to help them to effectively save their production logistics costs, enhance their internal material management level and provide reference for shipbuilder’s change in traditional ways and realization of just-in-time (JIT production.

Design of an automatic production monitoring system on job shop manufacturing

Science.gov (United States)

Prasetyo, Hoedi; Sugiarto, Yohanes; Rosyidi, Cucuk Nur

2018-02-01

Every production process requires monitoring system, so the desired efficiency and productivity can be monitored at any time. This system is also needed in the job shop type of manufacturing which is mainly influenced by the manufacturing lead time. Processing time is one of the factors that affect the manufacturing lead time. In a conventional company, the recording of processing time is done manually by the operator on a sheet of paper. This method is prone to errors. This paper aims to overcome this problem by creating a system which is able to record and monitor the processing time automatically. The solution is realized by utilizing electric current sensor, barcode, RFID, wireless network and windows-based application. An automatic monitoring device is attached to the production machine. It is equipped with a touch screen-LCD so that the operator can use it easily. Operator identity is recorded through RFID which is embedded in his ID card. The workpiece data are collected from the database by scanning the barcode listed on its monitoring sheet. A sensor is mounted on the machine to measure the actual machining time. The system's outputs are actual processing time and machine's capacity information. This system is connected wirelessly to a workshop planning application belongs to the firm. Test results indicated that all functions of the system can run properly. This system successfully enables supervisors, PPIC or higher level management staffs to monitor the processing time quickly with a better accuracy.

The Science Shop for Physics: an interface between practical problems in society and physical knowledge

Science.gov (United States)

van den Berg, G. P.

1998-03-01

Since some 20 years most Dutch universities have one or more science shops. Central shops handle research questions for all disciplines. Specialized shops are part of a department of chemistry or medicine, history, social science, etc. The shops have evolved rather differently, but their main mission still is to help social groups that lack money and have no easy access to scientific knowledge, e.g. neighbourhood, environmental, third world or patient groups. Most also help non-commercial organizations such as schools, trade unions or local authorities. Low-cost help can be provided because students do the work as part of their training, mainly in student projects (literature search, practical work, graduation, etc.). A total staff of 80, helped by 600 students, 250 voluntary and 50 paid researchers, handle 1500 questions resulting in 300 reports (estimated figures 1995). Science shops for physics (`Physics Shop', PS) have to deal with practical problems, generally involving classical physics. Major topics are noise, vibration, radiation, indoor climate and energy: most of the work lies in estimating/measuring relevant parameters, assessing impact, seeking solutions. The 3 Dutch PS's have developed in different directions. One is run entirely by students and deals with small, concrete problems. The second PS is managed by a co-ordinator who mediates between client groups and physics staff members who assist students in small and larger projects. The third has a lot of in-house expertise, and the shop staff is in direct contact with client groups as well as students who work in the PS itself. In questions submitted to the PS it is not always immediately clear what to do or how to do it because of the non-scientific phrasing of the problems and problems include non-physical (e.g. technical, health or legal) aspects. Also, difficulties in solving the problems are typically not in the underlying physics, but in the lack of accurate data and of control of the complex

The Relationship between Managerial Satisfaction and Job Turnover Intention: The Mediating Role of Job Satisfaction

Directory of Open Access Journals (Sweden)

Rüveyda Öztürk Basol

2017-09-01

Full Text Available The growth of service sector in Turkey occurs faster than the other sectors and the number of shopping malls increases correspondingly. The rapid growth of the number of shopping malls has necessitated the measurement of the attitudes of the employees in this sector. This study demonstrated that the gender, marital status and age were not the significant variables on job satisfaction, managerial satisfaction and job turnover intention; however, education status and income status were found to be significant variables on job satisfaction and job turnover intention. In addition, job satisfaction fully mediated the relationship between managerial satisfaction and job turnover intention.

Selective methodology of population dynamics for optimizing a multiobjective environment of job shop production

Directory of Open Access Journals (Sweden)

Santiago Ruiz

2015-01-01

Full Text Available This paper develops a methodology based on population genetics to improve the performance of two or more variables in job shop production systems. The methodology applies a genetic algorithm with special features in the individual selection when they pass from generation to generation. In comparison with the FIFO method, the proposed methodology showed better results in the variables makespan, idle time and energy cost. When compared with NSGA II, the methodology did not showed relevant differences in makespan and idle time; however better performance was obtained in energy cost and, especially, in the number of required iterations to get the optimal makespan.

Regras de prioridade eficientes que exploram características do Job Shop Flexível para a minimização do atraso total

Directory of Open Access Journals (Sweden)

Everton Luiz de Melo

2015-03-01

Full Text Available Este trabalho aborda o ambiente de produção Job Shop Flexível (JSF, extensão do problema NP-Difícil Job Shop. O JSF envolve um conjunto de jobs compostos por operações e cada operação deve ser processada em uma das máquinas habilitadas. O critério considerado é a minimização do atraso total. Inicialmente são identificadas características relacionadas à flexibilidade do sistema de produção, mais especificamente às máquinas habilitadas por operação e aos seus tempos de processamento. A seguir são propostas novas regras que exploram tais características e que são capazes de antever estados futuros do sistema. São realizados experimentos computacionais com 600 instâncias. Comparações com regras da literatura mostram que a melhor heurística proposta supera a melhor regra conhecida em 81% das instâncias.

Ant colony optimisation for scheduling of flexible job shop with multi-resources requirements

Directory of Open Access Journals (Sweden)

Kalinowski Krzysztof

2017-01-01

Full Text Available The paper presents application of ant colony optimisation algorithm for scheduling multi-resources operations in flexible job shop type of production systems. Operations that require the participation of two or more resources are common in industrial practice, when planning are subject not only machines, but also other additional resources (personnel, tools, etc.. Resource requirements of operation are indicated indirectly by resource groups. The most important parameters of the resource model and resource groups are also described. A basic assumptions for ant colony algorithm used for scheduling in the considered model with multiresources requirements of operations is discussed. The main result of the research is the schema of metaheuristic that enables searching best-score solutions in manufacturing systems satisfying presented constraints.

Optimal Results and Numerical Simulations for Flow Shop Scheduling Problems

Directory of Open Access Journals (Sweden)

Tao Ren

2012-01-01

Full Text Available This paper considers the m-machine flow shop problem with two objectives: makespan with release dates and total quadratic completion time, respectively. For Fm|rj|Cmax, we prove the asymptotic optimality for any dense scheduling when the problem scale is large enough. For Fm‖ΣCj2, improvement strategy with local search is presented to promote the performance of the classical SPT heuristic. At the end of the paper, simulations show the effectiveness of the improvement strategy.

Future Shop: A Model Career Placement & Transition Laboratory.

Science.gov (United States)

Floyd, Deborah L.; And Others

During 1988-89, the Collin County Community College District (CCCCD) conducted a project to develop, implement, and evaluate a model career laboratory called a "Future Shop." The laboratory was designed to let users explore diverse career options, job placement opportunities, and transfer resources. The Future Shop lab had three major components:…

A discrete firefly meta-heuristic with local search for makespan minimization in permutation flow shop scheduling problems

Directory of Open Access Journals (Sweden)

Nader Ghaffari-Nasab

2010-07-01

Full Text Available During the past two decades, there have been increasing interests on permutation flow shop with different types of objective functions such as minimizing the makespan, the weighted mean flow-time etc. The permutation flow shop is formulated as a mixed integer programming and it is classified as NP-Hard problem. Therefore, a direct solution is not available and meta-heuristic approaches need to be used to find the near-optimal solutions. In this paper, we present a new discrete firefly meta-heuristic to minimize the makespan for the permutation flow shop scheduling problem. The results of implementation of the proposed method are compared with other existing ant colony optimization technique. The preliminary results indicate that the new proposed method performs better than the ant colony for some well known benchmark problems.

The Virtual Shopping Experience: using virtual presence to motivate online shopping

Directory of Open Access Journals (Sweden)

Carolyn Chin

2005-11-01

Full Text Available Online shopping has thus far tended to be a niche business – highly successful in selling digital products such as shares, software and, increasingly, music and films, it has been less successful in persuading the purchasers of ‘traditional’ goods such as cars, clothes, toiletries, or household appliances to forsake their physical retailers and move into cyberspace. In this wide-ranging review paper we investigate the issue of the virtual experience – endeavouring to understand what is needed for a successful ‘shopping experience’ online and what the possible obstacles or pitfalls along the way might be. We initially introduce the concepts of virtual presence (the sense of ‘being there’ and virtual reality, discussing the possible roles both can play in providing a solution to the problem of effective online shopping. We then consider the Experience Economy, a concept which encapsulates many of the issues related to the problem of online shopping and which suggests ways in which online retailers can enhance the effectiveness of their sites by means of a virtual ‘experience’. Having set the scene for online shopping, we discuss eTailing today in terms of direct product experience and the opportunities which cyber-shopping offers to replicate this process. Finally, we identify some of the possibilities and problems of online shopping today, illustrating the current status of virtual presence in retailing with two micro-cases of success and failure.

Parallel patterns determination in solving cyclic flow shop problem with setups

Directory of Open Access Journals (Sweden)

Bożejko Wojciech

2017-06-01

Full Text Available The subject of this work is the new idea of blocks for the cyclic flow shop problem with setup times, using multiple patterns with different sizes determined for each machine constituting optimal schedule of cities for the traveling salesman problem (TSP. We propose to take advantage of the Intel Xeon Phi parallel computing environment during so-called ’blocks’ determination basing on patterns, in effect significantly improving the quality of obtained results.

The Relationship between Managerial Satisfaction and Job Turnover Intention: The Mediating Role of Job Satisfaction

OpenAIRE

Rüveyda Öztürk Basol; Harun Demirkaya

2017-01-01

The growth of service sector in Turkey occurs faster than the other sectors and the number of shopping malls increases correspondingly. The rapid growth of the number of shopping malls has necessitated the measurement of the attitudes of the employees in this sector. This study demonstrated that the gender, marital status and age were not the significant variables on job satisfaction, managerial satisfaction and job turnover intention; however, education status and income...

Problems about online shopping and strategies%网购存在的问题及其对策

Institute of Scientific and Technical Information of China (English)

赵晓妮

2011-01-01

通过对当前网购状况的分析，认为网购中卖家的诚信问题、网络支付存在安全隐患、售后服务和物流服务相对滞后是常见的3个问题；而网购的运营模式不够完善、网络安全问题突出和物流服务相对滞后是导致问题的主要原因，并指出买家培养良好的网购习惯、政府管理部门和网站联合加强网购交易的安保措施、制定专门的相关法律为网购提供法律保障是解决这些问题的有效措施。%How to avoid the risk of the online shopping problems are worth paying attention to. This paper argues the existing three problems on online shopping, such as the seller＇s problems about lack of honesty in the process of online shopping;online payment security risks; after-sales service and logistics services. The author finds that the main causes are the shopping model is not perfect, network security issues are not reliable and logistics services lags behind. After analyzing the reasons about the problems, the paper points out that there are three effective measures to solve these problems： buyers should have a good habits about online shopping; the administrative departments of government and the webs of should enhance online trade security, and the government developments should lay down the special laws for the online shopping.

Problems militating against job satisfaction among librarians in ...

African Journals Online (AJOL)

The research work examined the problems militating against job satisfaction among librarians in academic libraries in Niger State , Nigeria. The aim is to identify the problems associated with job satisfaction among librarians in academic libraries in Niger State. the population of the study was 58 librarians in Niger State.

Heuristic algorithms for the minmax regret flow-shop problem with interval processing times.

Science.gov (United States)

Ćwik, Michał; Józefczyk, Jerzy

2018-01-01

An uncertain version of the permutation flow-shop with unlimited buffers and the makespan as a criterion is considered. The investigated parametric uncertainty is represented by given interval-valued processing times. The maximum regret is used for the evaluation of uncertainty. Consequently, the minmax regret discrete optimization problem is solved. Due to its high complexity, two relaxations are applied to simplify the optimization procedure. First of all, a greedy procedure is used for calculating the criterion's value, as such calculation is NP-hard problem itself. Moreover, the lower bound is used instead of solving the internal deterministic flow-shop. The constructive heuristic algorithm is applied for the relaxed optimization problem. The algorithm is compared with previously elaborated other heuristic algorithms basing on the evolutionary and the middle interval approaches. The conducted computational experiments showed the advantage of the constructive heuristic algorithm with regards to both the criterion and the time of computations. The Wilcoxon paired-rank statistical test confirmed this conclusion.

Heuristics methods for the flow shop scheduling problem with separated setup times

Directory of Open Access Journals (Sweden)

Marcelo Seido Nagano

2012-06-01

Full Text Available This paper deals with the permutation flow shop scheduling problem with separated machine setup times. As a result of an investigation on the problem characteristics, four heuristics methods are proposed with procedures of the construction sequencing solution by an analogy with the asymmetric traveling salesman problem with the objective of minimizing makespan. Experimental results show that one of the new heuristics methods proposed provide high quality solutions in comparisons with the evaluated methods considered in the literature.

English in the Garment Shops.

Science.gov (United States)

Verplaetse, Lorrie

This text for limited-English-speaking workers in the garment industry consits of illustrated vocabulary words, grammar lessons, narratives or brief readings, and exercises on employment-related topics. The first section focuses on shop talk, including job-specific vocabulary, simple expressions and explanations, social language, seeking and…

Nature of job and psychiatric problems: the experiences of industrial workers.

Science.gov (United States)

Perwez, Syed Khalid; Khalique, Abdul; Ramaseshan, H; Swamy, T N V R; Mansoor, Mohammed

2014-10-09

The present study aimed to examine the effect of nature of job (High risk/low risk) on psychiatric problems of 200 workers of Tata Motors Ltd. in Jamshedpur. The workers/participants were divided on the basis of the nature of their job (high/low risk) and their salary (high/low paid) resulting in four sub-groups with 50 participants respectively s. The Middlesex Hospital Questionnaire (M.H.Q) constructed by Crown and Crisp (1966) and adapted in Hindi by Srivastava and Bhat in 1974 was administered on the participants. Results clearly indicated that nature of job (high and low risk) played a significant role in creating psychiatric problems in workers. Workers doing high risk jobs showed a greater amount of psychiatric problems compared to workers doing low risk jobs in both high paid and low paid categories. Psychiatric problems included free-floating anxiety, obsessional traits and symptoms, phobic anxiety, somatic concomitants of anxiety, neurotic depression, and hysterical personality traits were seen more in high risk job workers. High risk job workers had significantly higher psychiatric problems compared to low risk job workers.

A proposal simulated annealing algorithm for proportional parallel flow shops with separated setup times

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Helio Yochihiro Fuchigami

2014-08-01

Full Text Available This article addresses the problem of minimizing makespan on two parallel flow shops with proportional processing and setup times. The setup times are separated and sequence-independent. The parallel flow shop scheduling problem is a specific case of well-known hybrid flow shop, characterized by a multistage production system with more than one machine working in parallel at each stage. This situation is very common in various kinds of companies like chemical, electronics, automotive, pharmaceutical and food industries. This work aimed to propose six Simulated Annealing algorithms, their perturbation schemes and an algorithm for initial sequence generation. This study can be classified as “applied research” regarding the nature, “exploratory” about the objectives and “experimental” as to procedures, besides the “quantitative” approach. The proposed algorithms were effective regarding the solution and computationally efficient. Results of Analysis of Variance (ANOVA revealed no significant difference between the schemes in terms of makespan. It’s suggested the use of PS4 scheme, which moves a subsequence of jobs, for providing the best percentage of success. It was also found that there is a significant difference between the results of the algorithms for each value of the proportionality factor of the processing and setup times of flow shops.

Tendências de aplicações da otimização por colônia de formigas na progamação de JOB-SHOPS

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Felipe Fonseca Tavares de Freitas

2009-11-01

Full Text Available A programação da produção revela-se como uma atividade que, se bem planejada, otimizada e controlada, gera grandes vantagens competitivas e duradouras para a empresa. Um dos problemas mais complexos de programação da produção ocorre em sistemas do tipo job-shop – os quais envolvem otimização combinatória, cuja resolução em tempo computacional aceitável é quase sempre improvável (NP-hard. Neste contexto, vários métodos de otimização têm sido pesquisados e desenvolvidos nas últimas décadas, almejando-se planos de produção cada vez melhores, sob tempos de execução computacional gradativamente menores e viáveis para a indústria. Em especial, destaca-se o uso das técnicas de inteligência coletiva que, mimetizando fenômenos biológicos e sociais da natureza, vêm obtendo bons resultados quando aplicadas a problemas do tipo job shop scheduling (JSS. Revisando-se a teoria referente à meta-heurística de Otimização por Colônia de Formigas (ou Ant Colony Optimization - ACO e suas aplicações em problemas de JSS, este artigo identifica e explica as principais tendências de pesquisa nessa área, tanto a nível mundial quanto nacional. Como resultados deste estudo, pode-se vislumbrar a hibridização entre ACO e outros algoritmos de otimização e o tratamento de cenários de JSS cada vez mais complexos como as tendências mais relevantes dos trabalhos envolvendo ACO e problemas de programação de job-shops.

A framework for dynamic rescheduling problems

DEFF Research Database (Denmark)

Larsen, Rune; Pranzo, Marco

2018-01-01

. Extensive tests are carried out for the job shop problem, and we demonstrate that the framework can be used to ascertain the benefit of using rescheduling over static methods, decide between rescheduling policies, and finally we show that it can be applied in real-life applications due to a low time...

Heuristic for production scheduling on job-shop plants considering preventive maintenance tasks

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Ronald Díaz-Cazaña

2014-01-01

Full Text Available El análisis simultáneo de la programación de la producción y la s tareas de mantenimiento preventivo atrae especial atención en los investigadores debido a su gran complejidad y por ende la neces idad de encontrar métodos eficientes para resolver este tipo de problema combinatorio. Este artículo presenta un enfoque heurístico para resolver dicha problemática en plantas tipo job-shop . El método de solución incluye un modelo de programación lineal inspirado en el proble ma del Agente Vendedor, donde el tiempo de iniciación es consid erado como métrica de distancia. El método persigue obtener una secue ncia de las órdenes de producción y tareas de mantenimiento pre ventivo que reduzcan el tiempo ocioso y los retrasos simultáneamente, c umpliendo con el programa de mantenimiento. Luego de encontrar la solución óptima para cada máquina, un factor de corrección ( CF es determinado como la nueva medida de distancia. El factor CF considera la estructura inicial de solución, la utilización de las máquin as y las prioridades en los productos. De esta forma, la soluci ón final es alcanzada solucionando el modelo de programación lineal usando los valores de distancia actualizados. Finalmente, la heurístic a propuesta es aplicada en un caso de estudio real de la Industria Cubana. Los resultados experimentales indicaron una reducción significa tiva del tiempo ocioso para la compañía objeto de estudio.

Evaluating the performance of constructive heuristics for the blocking flow shop scheduling problem with setup times

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Mauricio Iwama Takano

2019-01-01

Full Text Available This paper addresses the minimization of makespan for the permutation flow shop scheduling problem with blocking and sequence and machine dependent setup times, a problem not yet studied in previous studies. The 14 best known heuristics for the permutation flow shop problem with blocking and no setup times are pre-sented and then adapted to the problem in two different ways; resulting in 28 different heuristics. The heuristics are then compared using the Taillard database. As there is no other work that addresses the problem with blocking and sequence and ma-chine dependent setup times, a database for the setup times was created. The setup time value was uniformly distributed between 1% and 10%, 50%, 100% and 125% of the processing time value. Computational tests are then presented for each of the 28 heuristics, comparing the mean relative deviation of the makespan, the computational time and the percentage of successes of each method. Results show that the heuristics were capable of providing interesting results.

Comparison of Firefly algorithm and Artificial Immune System algorithm for lot streaming in -machine flow shop scheduling

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G. Vijay Chakaravarthy

2012-11-01

Full Text Available Lot streaming is a technique used to split the processing of lots into several sublots (transfer batches to allow the overlapping of operations in a multistage manufacturing systems thereby shortening the production time (makespan. The objective of this paper is to minimize the makespan and total flow time of -job, -machine lot streaming problem in a flow shop with equal and variable size sublots and also to determine the optimal sublot size. In recent times researchers are concentrating and applying intelligent heuristics to solve flow shop problems with lot streaming. In this research, Firefly Algorithm (FA and Artificial Immune System (AIS algorithms are used to solve the problem. The results obtained by the proposed algorithms are also compared with the performance of other worked out traditional heuristics. The computational results shows that the identified algorithms are more efficient, effective and better than the algorithms already tested for this problem.

A Bee Colony Optimization Approach for Mixed Blocking Constraints Flow Shop Scheduling Problems

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Mostafa Khorramizadeh

2015-01-01

Full Text Available The flow shop scheduling problems with mixed blocking constraints with minimization of makespan are investigated. The Taguchi orthogonal arrays and path relinking along with some efficient local search methods are used to develop a metaheuristic algorithm based on bee colony optimization. In order to compare the performance of the proposed algorithm, two well-known test problems are considered. Computational results show that the presented algorithm has comparative performance with well-known algorithms of the literature, especially for the large sized problems.

Algoritmo genético aplicado a la programación en talleres de maquinado//Genetic algorithm applied to scheduling in machine shops

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José Eduardo Márquez-Delgado

2012-09-01

Full Text Available En este trabajo se utiliza la metaheurística nombrada algoritmo genético, para dos variantes típicas de problemas de planificación presentes en un taller de maquinado de piezas: las variantes flujo general y flujo regular, y se ha seleccionado la minimización del tiempo de finalización de todos los trabajos ocamino máximo, como objetivo a optimizar en un plan de trabajo. Este problema es considerado de difícil solución y es típico de la optimización combinatoria. Los resultados demuestran la calidad de las soluciones encontradas en correspondencia con el tiempo de cómputo empleado, al ser comparados conproblemas clásicos reportados por otros autores. La representación propuesta de cada cromosoma genera el universo completo de soluciones factibles, donde es posible encontrar valores óptimos globales de solución y cumple con las restricciones del problema.Palabras claves: algoritmo genético, cromosomas, flujo general, flujo regular, planificación, camino máximo._____________________________________________________________________________AbstractIn this paper we use the metaheuristic named genetic algorithm, for two typical variants of problems of scheduling present in a in a machine shop parts: the variant job shop and flow shop, and the minimization of the time of finalization of all the works has been selected, good known as makespan, as objective tooptimize in a work schedule. This problem is considered to be a difficult solution and is typical in combinatory optimization. The results demonstrate the quality of the solutions found in correspondence with the time of used computation, when being compared with classic problems reported by other authors.The proposed representation of each chromosome generates the complete universe of feasible solutions, where it is possible to find global good values of solution and it fulfills the restrictions of the problem.Key words: genetic algorithm, chromosomes, flow shop, job shop

The One-Stop Job Shop.

Science.gov (United States)

Kiser, Kim

1998-01-01

Minnesota's WorkForce Centers are a model of state employment services. The centers assist those in need of initiatives such as dislocated worker programs, welfare-to-work services, services for the blind, employment-and-training programs, veterans' services, and job-search assistance. (JOW)

Job shop fails choosy nurses.

Science.gov (United States)

1993-10-13

Only 181 people have used the Clearing House set up to find jobs for redundant London nurses. And almost a quarter have rejected the posts which it says are suitable for them, with 21 per cent of employers turning down candidates selected by the initiative.

Why Shops Close Again : An Evolutionary Perspective on the Deregulation of Shopping Hours

NARCIS (Netherlands)

Kosfeld, M.

1999-01-01

This paper introduces a new perspective on the deregulation of shopping hours based on ideas from evolutionary game theory. We study a retail economy where shopping hours have been deregulated recently. It is argued that first, the deregulation leads to a coordination problem between store owners

Why Shops Close Again : An Evolutionary Perspective on the Deregulation of Shopping Hours

OpenAIRE

Kosfeld, M.

1999-01-01

This paper introduces a new perspective on the deregulation of shopping hours based on ideas from evolutionary game theory. We study a retail economy where shopping hours have been deregulated recently. It is argued that first, the deregulation leads to a coordination problem between store owners and customers, and second, the ‘solution’ to this problem depends on the specific cost structure of stores and the preferences of customers. In particular, it may happen that, even if extended shoppi...

Flow shop scheduling with heterogeneous workers

OpenAIRE

Benavides, Alexander J.; Ritt, Marcus; Miralles Insa, Cristóbal Javier

2014-01-01

We propose an extension to the flow shop scheduling problem named Heterogeneous Flow Shop Scheduling Problem (Het-FSSP), where two simultaneous issues have to be resolved: finding the best worker assignment to the workstations, and solving the corresponding scheduling problem. This problem is motivated by Sheltered Work centers for Disabled, whose main objective is the labor integration of persons with disabilities, an important aim not only for these centers but for any company d...

Problems in the online marketing of online shops in China : Case study: the Taobao online marketing policy

OpenAIRE

Ding, Lu

2013-01-01

With the development and popularization of the Internet, more and more people are choosing to trade via the Internet. For the Chinese market, online marketing is still in its infancy, and inevitably several problems exist. Taobao is the fastest developing of all online marketing shopping platforms in China and accounts for the largest share of the online shopping market. In such a rapidly expanding market, Taobao's rise is a cause for concern. This thesis will examine the current online m...

On the Integrated Job Scheduling and Constrained Network Routing Problem

DEFF Research Database (Denmark)

Gamst, Mette

This paper examines the NP-hard problem of scheduling a number of jobs on a finite set of machines such that the overall profit of executed jobs is maximized. Each job demands a number of resources, which must be sent to the executing machine via constrained paths. Furthermore, two resource demand...

Towards an understanding of Internet-based problem shopping behaviour: The concept of online shopping addiction and its proposed predictors

Science.gov (United States)

ROSE, SUSAN; DHANDAYUDHAM, ARUN

2014-01-01

Background: Compulsive and addictive forms of consumption and buying behaviour have been researched in both business and medical literature. Shopping enabled via the Internet now introduces new features to the shopping experience that translate to positive benefits for the shopper. Evidence now suggests that this new shopping experience may lead to problematic online shopping behaviour. This paper provides a theoretical review of the literature relevant to online shopping addiction (OSA). Based on this selective review, a conceptual model of OSA is presented. Method: The selective review of the literature draws on searches within databases relevant to both clinical and consumer behaviour literature including EBSCO, ABI Pro-Quest, Web of Science – Social Citations Index, Medline, PsycINFO and Pubmed. The article reviews current thinking on problematic, and specifically addictive, behaviour in relation to online shopping. Results: The review of the literature enables the extension of existing knowledge into the Internet-context. A conceptual model of OSA is developed with theoretical support provided for the inclusion of 7 predictor variables: low self-esteem, low self-regulation; negative emotional state; enjoyment; female gender; social anonymity and cognitive overload. The construct of OSA is defined and six component criteria of OSA are proposed based on established technological addiction criteria. Conclusions: Current Internet-based shopping experiences may trigger problematic behaviours which can be classified on a spectrum which at the extreme end incorporates OSA. The development of a conceptual model provides a basis for the future measurement and testing of proposed predictor variables and the outcome variable OSA. PMID:25215218

Towards an understanding of Internet-based problem shopping behaviour: The concept of online shopping addiction and its proposed predictors.

Science.gov (United States)

Rose, Susan; Dhandayudham, Arun

2014-06-01

Compulsive and addictive forms of consumption and buying behaviour have been researched in both business and medical literature. Shopping enabled via the Internet now introduces new features to the shopping experience that translate to positive benefits for the shopper. Evidence now suggests that this new shopping experience may lead to problematic online shopping behaviour. This paper provides a theoretical review of the literature relevant to online shopping addiction (OSA). Based on this selective review, a conceptual model of OSA is presented. The selective review of the literature draws on searches within databases relevant to both clinical and consumer behaviour literature including EBSCO, ABI Pro-Quest, Web of Science - Social Citations Index, Medline, PsycINFO and Pubmed. The article reviews current thinking on problematic, and specifically addictive, behaviour in relation to online shopping. The review of the literature enables the extension of existing knowledge into the Internet-context. A conceptual model of OSA is developed with theoretical support provided for the inclusion of 7 predictor variables: low self-esteem, low self-regulation; negative emotional state; enjoyment; female gender; social anonymity and cognitive overload. The construct of OSA is defined and six component criteria of OSA are proposed based on established technological addiction criteria. Current Internet-based shopping experiences may trigger problematic behaviours which can be classified on a spectrum which at the extreme end incorporates OSA. The development of a conceptual model provides a basis for the future measurement and testing of proposed predictor variables and the outcome variable OSA.

Proposed algorithm to improve job shop production scheduling using ant colony optimization method

Science.gov (United States)

Pakpahan, Eka KA; Kristina, Sonna; Setiawan, Ari

2017-12-01

This paper deals with the determination of job shop production schedule on an automatic environment. On this particular environment, machines and material handling system are integrated and controlled by a computer center where schedule were created and then used to dictate the movement of parts and the operations at each machine. This setting is usually designed to have an unmanned production process for a specified interval time. We consider here parts with various operations requirement. Each operation requires specific cutting tools. These parts are to be scheduled on machines each having identical capability, meaning that each machine is equipped with a similar set of cutting tools therefore is capable of processing any operation. The availability of a particular machine to process a particular operation is determined by the remaining life time of its cutting tools. We proposed an algorithm based on the ant colony optimization method and embedded them on matlab software to generate production schedule which minimize the total processing time of the parts (makespan). We test the algorithm on data provided by real industry and the process shows a very short computation time. This contributes a lot to the flexibility and timelines targeted on an automatic environment.

Job Grading Standard for Materials Expediter WG-6705.

Science.gov (United States)

Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

The standard is used to grade nonsupervisory jobs involved in routing and expediting the movement of parts, end items, supplies, and materials within production and repair facilities to meet priority needs. The work requires knowledge of material characteristics, uses, condition, industrial production shop procedures, shop layout, and internal…

Variable Neighborhood Search for Parallel Machines Scheduling Problem with Step Deteriorating Jobs

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Wenming Cheng

2012-01-01

Full Text Available In many real scheduling environments, a job processed later needs longer time than the same job when it starts earlier. This phenomenon is known as scheduling with deteriorating jobs to many industrial applications. In this paper, we study a scheduling problem of minimizing the total completion time on identical parallel machines where the processing time of a job is a step function of its starting time and a deteriorating date that is individual to all jobs. Firstly, a mixed integer programming model is presented for the problem. And then, a modified weight-combination search algorithm and a variable neighborhood search are employed to yield optimal or near-optimal schedule. To evaluate the performance of the proposed algorithms, computational experiments are performed on randomly generated test instances. Finally, computational results show that the proposed approaches obtain near-optimal solutions in a reasonable computational time even for large-sized problems.

Young Consumers’ Perception of Problems and Usefulness of Mobile Shopping Applications

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Blaženka Knežević

2017-03-01

Full Text Available Objective: The objective of this paper is to explain how young consumers from Croatia perceive problems and usefulness of mobile shopping applications. Research Design & Methods: The paper is based on descriptive statistics of data collected in a wide-range survey on mobile commerce attitudes within young population in Croatia. The questionnaire was designed upon recent literature in the fields of electronic and mobile commerce. The quantitative data analysis regarding mobile application problems and usefulness was conducted on 276 validated questionnaires. Findings: The majority of young population in Croatia is experienced in smartphone usage and can be referred to as “handset generation”. They express a high level of satisfaction regarding mobile purchasing and have positive attitudes towards the usefulness of mobile shopping applications. They are aware of mobile purchasing obstacles and risks and perceive some of them as very important. Implications & Recommendations: The results of this study can be useful for researchers and practitioners in the retail industry. The findings can be used as a basis for adjusting policies towards mobile commerce within business strategies, not only in the retailing industry, but in other industries as well. Contribution & Value Added: The paper is a valuable contribution to research fields of retail marketing, retail management, electronic commerce and, especially, mobile commerce because it deals with primary data collected in a specific geographical market. As the authors developed their own set of questions, the presented findings can be used as a basis for future research in various markets and groups of consumers.

Machine shop basics

CERN Document Server

Miller, Rex

2004-01-01

Use the right tool the right wayHere, fully updated to include new machines and electronic/digital controls, is the ultimate guide to basic machine shop equipment and how to use it. Whether you're a professional machinist, an apprentice, a trade student, or a handy homeowner, this fully illustrated volume helps you define tools and use them properly and safely. It's packed with review questions for students, and loaded with answers you need on the job.Mark Richard Miller is a Professor and Chairman of the Industrial Technology Department at Texas A&M University in Kingsville, T

A novel modeling approach for job shop scheduling problem under uncertainty

Directory of Open Access Journals (Sweden)

Behnam Beheshti Pur

2013-11-01

Full Text Available When aiming on improving efficiency and reducing cost in manufacturing environments, production scheduling can play an important role. Although a common workshop is full of uncertainties, when using mathematical programs researchers have mainly focused on deterministic problems. After briefly reviewing and discussing popular modeling approaches in the field of stochastic programming, this paper proposes a new approach based on utility theory for a certain range of problems and under some practical assumptions. Expected utility programming, as the proposed approach, will be compared with the other well-known methods and its meaningfulness and usefulness will be illustrated via a numerical examples and a real case.

Effective Iterated Greedy Algorithm for Flow-Shop Scheduling Problems with Time lags

Science.gov (United States)

ZHAO, Ning; YE, Song; LI, Kaidian; CHEN, Siyu

2017-05-01

Flow shop scheduling problem with time lags is a practical scheduling problem and attracts many studies. Permutation problem(PFSP with time lags) is concentrated but non-permutation problem(non-PFSP with time lags) seems to be neglected. With the aim to minimize the makespan and satisfy time lag constraints, efficient algorithms corresponding to PFSP and non-PFSP problems are proposed, which consist of iterated greedy algorithm for permutation(IGTLP) and iterated greedy algorithm for non-permutation (IGTLNP). The proposed algorithms are verified using well-known simple and complex instances of permutation and non-permutation problems with various time lag ranges. The permutation results indicate that the proposed IGTLP can reach near optimal solution within nearly 11% computational time of traditional GA approach. The non-permutation results indicate that the proposed IG can reach nearly same solution within less than 1% computational time compared with traditional GA approach. The proposed research combines PFSP and non-PFSP together with minimal and maximal time lag consideration, which provides an interesting viewpoint for industrial implementation.

Exact and heuristic solution approaches for the Integrated Job Scheduling and Constrained Network Routing Problem

DEFF Research Database (Denmark)

Gamst, M.

2014-01-01

problem. The methods are computationally evaluated on test instances arising from telecommunications with up to 500 jobs and 500 machines. Results show that solving the integrated job scheduling and constrained network routing problem to optimality is very difficult. The exact solution approach performs......This paper examines the problem of scheduling a number of jobs on a finite set of machines such that the overall profit of executed jobs is maximized. Each job has a certain demand, which must be sent to the executing machine via constrained paths. A job cannot start before all its demands have...... arrived at the machine. Furthermore, two resource demand transmissions cannot use the same edge in the same time period. The problem has application in grid computing, where a number of geographically distributed machines work together for solving large problems. The machines are connected through...

A New Approach to Solve Flowshop Scheduling Problems by Artificial Immune Systems = Akış Tipi Çizelgeleme Problemlerinin Yapay Bağışıklık Sistemleri ile Çözümünde Yeni Bir Yaklaşım

Directory of Open Access Journals (Sweden)

Alper DÖYEN

2007-01-01

Full Text Available The n-job, m-machine flow shop scheduling problem is one of the most general job scheduling problems. This study deals with the criteria of makespan minimization for the flow shop scheduling problem. Artificial Immune Systems (AIS are new intelligent problem solving techniques that are being used in scheduling problems. AIS can be defined as computational systems inspired by theoretical immunology, observed immune functions, principles and mechanisms in order to solve problems. In this research, a computational method based on clonal selection principle and affinity maturation mechanisms of the immune response is used. The operation parameters of meta-heuristics have an important role on the quality of the solution. Thus, a generic systematic procedure which bases on a multi-step experimental design approach for determining the efficient system parameters for AIS is presented. Experimental results show that, the artificial immune system algorithm is more efficient than both the classical heuristic flow shop scheduling algorithms and simulated annealing.

A multi-objective optimization problem for multi-state series-parallel systems: A two-stage flow-shop manufacturing system

International Nuclear Information System (INIS)

Azadeh, A.; Maleki Shoja, B.; Ghanei, S.; Sheikhalishahi, M.

2015-01-01

This research investigates a redundancy-scheduling optimization problem for a multi-state series parallel system. The system is a flow shop manufacturing system with multi-state machines. Each manufacturing machine may have different performance rates including perfect performance, decreased performance and complete failure. Moreover, warm standby redundancy is considered for the redundancy allocation problem. Three objectives are considered for the problem: (1) minimizing system purchasing cost, (2) minimizing makespan, and (3) maximizing system reliability. Universal generating function is employed to evaluate system performance and overall reliability of the system. Since the problem is in the NP-hard class of combinatorial problems, genetic algorithm (GA) is used to find optimal/near optimal solutions. Different test problems are generated to evaluate the effectiveness and efficiency of proposed approach and compared to simulated annealing optimization method. The results show the proposed approach is capable of finding optimal/near optimal solution within a very reasonable time. - Highlights: • A redundancy-scheduling optimization problem for a multi-state series parallel system. • A flow shop with multi-state machines and warm standby redundancy. • Objectives are to optimize system purchasing cost, makespan and reliability. • Different test problems are generated and evaluated by a unique genetic algorithm. • It locates optimal/near optimal solution within a very reasonable time

Concurrent validation of a neurocognitive assessment protocol for clients with mental illness in job matching as shop sales in supported employment.

Science.gov (United States)

Ng, S S W; Lak, D C C; Lee, S C K; Ng, P P K

2015-03-01

Occupational therapists play a major role in the assessment and referral of clients with severe mental illness for supported employment. Nonetheless, there is scarce literature about the content and predictive validity of the process. In addition, the criteria of successful job matching have not been analysed and job supervisors have relied on experience rather than objective standards in recruitment. This study aimed to explore the profile of successful clients working in 'shop sales' in a supportive environment using a neurocognitive assessment protocol, and to validate the protocol against 'internal standards' of the job supervisors. This was a concurrent validation study of criterion-related scales for a single job type. The subjective ratings from the supervisors were concurrently validated against the results of neurocognitive assessment of intellectual function and work-related cognitive behaviour. A regression model was established for clients who succeeded and failed in employment using supervisor's ratings and a cutoff value of 10.5 for the Performance Fitness Rating Scale (R(2) = 0.918, F[41] = 3.794, p = 0.003). Classification And Regression Tree was also plotted to identify the profile of cases, with an overall accuracy of 0.861 (relative error, 0.26). Use of both inference statistics and data mining techniques enables the decision tree of neurocognitive assessments to be more readily applied by therapists in vocational rehabilitation, and thus directly improve the efficiency and efficacy of the process.

Asymptotic Analysis of SPTA-Based Algorithms for No-Wait Flow Shop Scheduling Problem with Release Dates

Directory of Open Access Journals (Sweden)

Tao Ren

2014-01-01

Full Text Available We address the scheduling problem for a no-wait flow shop to optimize total completion time with release dates. With the tool of asymptotic analysis, we prove that the objective values of two SPTA-based algorithms converge to the optimal value for sufficiently large-sized problems. To further enhance the performance of the SPTA-based algorithms, an improvement scheme based on local search is provided for moderate scale problems. New lower bound is presented for evaluating the asymptotic optimality of the algorithms. Numerical simulations demonstrate the effectiveness of the proposed algorithms.

Asymptotic analysis of SPTA-based algorithms for no-wait flow shop scheduling problem with release dates.

Science.gov (United States)

Ren, Tao; Zhang, Chuan; Lin, Lin; Guo, Meiting; Xie, Xionghang

2014-01-01

We address the scheduling problem for a no-wait flow shop to optimize total completion time with release dates. With the tool of asymptotic analysis, we prove that the objective values of two SPTA-based algorithms converge to the optimal value for sufficiently large-sized problems. To further enhance the performance of the SPTA-based algorithms, an improvement scheme based on local search is provided for moderate scale problems. New lower bound is presented for evaluating the asymptotic optimality of the algorithms. Numerical simulations demonstrate the effectiveness of the proposed algorithms.

Nonstrict vector simulation in multi-operation scheduling

NARCIS (Netherlands)

Sevastianov, S.V.

1995-01-01

We consider several multi??operation scheduling problems with m machines and n jobs??, including fl??ow shop??, open shop,?? assembly line,?? and a few special cases of job shop with the makespan criterion. It is demonstrated that the problems in question can be effi??ciently solved by approximation

Job dissatisfaction as a contributor to stress-related mental health problems among Japanese civil servants.

Science.gov (United States)

Tatsuse, Takashi; Sekine, Michikazu

2013-01-01

Although studies on the association of job dissatisfaction with mental health have been conducted in the past, few studies have dealt with the complicated links connecting job stress, job dissatisfaction, and stress-related illness. This study seeks to determine how job dissatisfaction is linked to common mental health issues. This study surveyed 3,172 civil servants (2,233 men and 939 women) in 1998, taking poor mental functioning, fatigue, and sleep disturbance as stress-related mental health problems. We examine how psychosocial risk factors at work and job dissatisfaction are associated independently with poor mental functioning, fatigue, and sleep disturbance after adjustment for other known risk factors, and how job dissatisfaction contributes to change in the degree of association between psychosocial risk factors at work and mental health problems. In general, psychosocial risk factors were independently associated with mental health problems. When adjusted for job dissatisfaction, not only was job satisfaction independently associated with mental health problems but it was also found that the association of psychosocial risk factors with mental health problems declined. Our results suggest that, although longitudinal research is necessary, attitudes toward satisfaction at work can potentially decrease the negative effects of psychosocial risk factors at work on mental health.

New Mathematical Model and Algorithm for Economic Lot Scheduling Problem in Flexible Flow Shop

Directory of Open Access Journals (Sweden)

H. Zohali

2018-03-01

Full Text Available This paper addresses the lot sizing and scheduling problem for a number of products in flexible flow shop with identical parallel machines. The production stages are in series, while separated by finite intermediate buffers. The objective is to minimize the sum of setup and inventory holding costs per unit of time. The available mathematical model of this problem in the literature suffers from huge complexity in terms of size and computation. In this paper, a new mixed integer linear program is developed for delay with the huge dimentions of the problem. Also, a new meta heuristic algorithm is developed for the problem. The results of the numerical experiments represent a significant advantage of the proposed model and algorithm compared with the available models and algorithms in the literature.

To Capture Dynamic Shop Floor Knowledge in Global Production Networks

DEFF Research Database (Denmark)

Madsen, Erik Skov; Riis, Jens Ove; Sørensen, Brian Vejrum

2007-01-01

­ing of the jobs to be transferred and has led to a changed focus for training new workers. Secondly, the paper will address how to capture the knowl­edge associated with carrying out these jobs. And third, planning the trans­fer process will be discussed to form a basis for future continuous improve...... industrial companies with plans to transfer production units to an­other location, this paper addresses  the initial steps of pursuing this issue by presenting and testing a model for identification of the activities, task and  knowledge on the shop floor jobs. This has provided a broader understand...

Machine Shop Practice. Trade and Industrial Education Course of Study.

Science.gov (United States)

Emerly, Robert J.; And Others

Designed for secondary school students who are interested in becoming machinists, this beginning course guide in machine shop practice is organized into the following sections: (1) Introduction, (2) instructional plan, (3) educational philosophy, (4) specific course objectives, (5) course outline, (6) job sheets, and (7) operation sheets. The…

Solving a large-scale precedence constrained scheduling problem with elastic jobs using tabu search

DEFF Research Database (Denmark)

Pedersen, C.R.; Rasmussen, R.V.; Andersen, Kim Allan

2007-01-01

This paper presents a solution method for minimizing makespan of a practical large-scale scheduling problem with elastic jobs. The jobs are processed on three servers and restricted by precedence constraints, time windows and capacity limitations. We derive a new method for approximating the server...... exploitation of the elastic jobs and solve the problem using a tabu search procedure. Finding an initial feasible solution is in general -complete, but the tabu search procedure includes a specialized heuristic for solving this problem. The solution method has proven to be very efficient and leads...

Integrating the sequence dependent setup time open shop problem and preventive maintenance policies

Directory of Open Access Journals (Sweden)

K. Naboureh

2016-09-01

Full Text Available In most industrial environments, it is usually considered that machines are accessible throughout the planning horizon, but in real situation, machines may be unavailable due to a scheduled preventive maintenance where the periods of unavailability are known in advance. The main idea of this paper is to consider different preventive maintenance policies on machines regarding open shop scheduling problem (OSSP with sequence dependent setup times (SDST using immune algorithm. The preventive maintenance (PM policies are planned for maximizing availability of machines or keeping minimum level of reliability through the production horizon. The objective function of the paper is to minimize makespan. In total, the proposed algorithm extensively is compared with six adaptations of existing heuristic and meta-heuristic methods for the problem through data sets from benchmarks based on Taillard’s instances with some adjustments. The results show that the proposed algorithm outperforms other algorithms for this problem.

Solving a large-scale precedence constrained scheduling problem with elastic jobs using tabu search

DEFF Research Database (Denmark)

Pedersen, C.R.; Rasmussen, R.V.; Andersen, Kim Allan

2007-01-01

exploitation of the elastic jobs and solve the problem using a tabu search procedure. Finding an initial feasible solution is in general -complete, but the tabu search procedure includes a specialized heuristic for solving this problem. The solution method has proven to be very efficient and leads......This paper presents a solution method for minimizing makespan of a practical large-scale scheduling problem with elastic jobs. The jobs are processed on three servers and restricted by precedence constraints, time windows and capacity limitations. We derive a new method for approximating the server...... to a significant decrease in makespan compared to the strategy currently implemented....

Science Shops

DEFF Research Database (Denmark)

Jørgensen, Michael Søgaard

1999-01-01

The paper prsents the overall concept of science shops as practised in most of the European science shops and present the concept practised and some experience obtained at the Technical University of Denmark. An outline for the planning of new sceince shops is presented.......The paper prsents the overall concept of science shops as practised in most of the European science shops and present the concept practised and some experience obtained at the Technical University of Denmark. An outline for the planning of new sceince shops is presented....

Tourist market segmentation by motivation to shop: A case study of Istanbul, Turkey

Directory of Open Access Journals (Sweden)

Egresi István

2017-01-01

Full Text Available Previous research has indicated that shopping could make up for a significant part of the tourist experience and could provide significant benefits to destinations by contributing to local retail revenue and by generating many jobs. In order to design better marketing strategies, destination managers must understand what attracts tourists to a destination and makes them shop while there. However, tourists represent a heterogeneous group and subgroups of individuals are motivated to visit a destination for a variety of reasons. The primary purpose of this study is to segment tourist shoppers visiting Istanbul according to their motivation to shop. Five distinctive groups of 'product-focused shoppers', 'shoppers for cultural experience', 'reluctant shoppers', 'difference seekers' and 'total shoppers' were found and compared by the geographical origin of the tourists, their socio-demographic characteristics, travel characteristics and behaviour, primary motivation for the trip, activity participation and shopping preferences and attitudes. The findings indicate that destination marketers must develop their strategies and marketing products to address the heterogeneity of motivations underlying tourist shopping.

FLOWSHOP SCHEDULING USING A NETWORK APPROACH ...

African Journals Online (AJOL)

eobe

time when the last job completes on the last machine. The objective ... more jobs in a permutation flow shop scheduling problem ... processing time of a job on a machine is zero, it ..... hybrid flow shops with sequence dependent setup times ...

Eyes Wide Shopped: Shopping Situations Trigger Arousal in Impulsive Buyers

Science.gov (United States)

Serfas, Benjamin G.; Büttner, Oliver B.; Florack, Arnd

2014-01-01

The present study proposes arousal as an important mechanism driving buying impulsiveness. We examined the effect of buying impulsiveness on arousal in non-shopping and shopping contexts. In an eye-tracking experiment, we measured pupil dilation while participants viewed and rated pictures of shopping scenes and non-shopping scenes. The results demonstrated that buying impulsiveness is closely associated with arousal as response to viewing pictures of shopping scenes. This pertained for hedonic shopping situations as well as for utilitarian shopping situations. Importantly, the effect did not emerge for non-shopping scenes. Furthermore, we demonstrated that arousal of impulsive buyers is independent from cognitive evaluation of scenes in the pictures. PMID:25489955

Eyes wide shopped: shopping situations trigger arousal in impulsive buyers.

Science.gov (United States)

Serfas, Benjamin G; Büttner, Oliver B; Florack, Arnd

2014-01-01

The present study proposes arousal as an important mechanism driving buying impulsiveness. We examined the effect of buying impulsiveness on arousal in non-shopping and shopping contexts. In an eye-tracking experiment, we measured pupil dilation while participants viewed and rated pictures of shopping scenes and non-shopping scenes. The results demonstrated that buying impulsiveness is closely associated with arousal as response to viewing pictures of shopping scenes. This pertained for hedonic shopping situations as well as for utilitarian shopping situations. Importantly, the effect did not emerge for non-shopping scenes. Furthermore, we demonstrated that arousal of impulsive buyers is independent from cognitive evaluation of scenes in the pictures.

Designing an advanced available-to-promise mechanism compatible with the make-to-forecast production systems through integrating inventory allocation and job shop scheduling with due dates and weighted earliness/tardiness cost

Directory of Open Access Journals (Sweden)

Masoud Rabbani

2016-06-01

Full Text Available In the competitive business world, applying a reliable and powerful mechanism to support decision makers in manufacturing companies and helping them save time by considering varieties of effective factors is an inevitable issue. Advanced Available-to-Promise is a perfect tool to design and perform such a mechanism. In this study, this mechanism which is compatible with the Make-to-Forecast production systems is presented. The ability to distinguish between batch mode and real-time mode advanced available-to-promise is one of the unique superiorities of the proposed model. We also try to strengthen this mechanism by integrating the inventory allocation and job shop scheduling by considering due dates and weighted earliness/tardiness cost that leads to more precise decisions. A mixed integer programming (MIP model and a heuristic algorithm according to its disability to solve large size problems are presented. The designed experiments and the obtained results have proved the efficiency of the proposed heuristic method.

Eyes wide shopped: shopping situations trigger arousal in impulsive buyers.

Directory of Open Access Journals (Sweden)

Benjamin G Serfas

Full Text Available The present study proposes arousal as an important mechanism driving buying impulsiveness. We examined the effect of buying impulsiveness on arousal in non-shopping and shopping contexts. In an eye-tracking experiment, we measured pupil dilation while participants viewed and rated pictures of shopping scenes and non-shopping scenes. The results demonstrated that buying impulsiveness is closely associated with arousal as response to viewing pictures of shopping scenes. This pertained for hedonic shopping situations as well as for utilitarian shopping situations. Importantly, the effect did not emerge for non-shopping scenes. Furthermore, we demonstrated that arousal of impulsive buyers is independent from cognitive evaluation of scenes in the pictures.

Trustworthy Online Shopping with Price Impact

Directory of Open Access Journals (Sweden)

Musial Jedrzej

2017-06-01

Full Text Available Internet shopping is one of the main pillars of electronic commerce.According to the literature, the Internet Shopping Optimization Problem (ISOPhas been defined in order to optimize the global cost of online purchase, taking into account both the cost of products and shipping. In this study, it was decided to propose and analyze a very interesting, and really substantial, extension of the ISOP.Namely, trust factors were subjected to careful analysis from the customer point of view. The analysis is based on a specially prepared questionnaire, supplemented by the information from the literature and our own observations. Thus, it was possible to propose a definition of a new mathematical model of the problem, and to prove its affiliation to the class of strongly NP-hard problems. In addition, the heuristic algorithm is proposed, which can be used to solve the problem.

Modeling the Hybrid Flow Shop Scheduling Problem Followed by an Assembly Stage Considering Aging Effects and Preventive Maintenance Activities

Directory of Open Access Journals (Sweden)

Seyyed Mohammad Hassan Hosseini

2016-05-01

Full Text Available Scheduling problem for the hybrid flow shop scheduling problem (HFSP followed by an assembly stage considering aging effects additional preventive and maintenance activities is studied in this paper. In this production system, a number of products of different kinds are produced. Each product is assembled with a set of several parts. The first stage is a hybrid flow shop to produce parts. All machines can process all kinds of parts in this stage but each machine can process only one part at the same time. The second stage is a single assembly machine or a single assembly team of workers. The aim is to schedule the parts on the machines and assembly sequence and also determine when the preventive maintenance activities get done in order to minimize the completion time of all products (makespan. A mathematical modeling is presented and its validation is shown by solving an example in small scale. Since this problem has been proved strongly NP-hard, in order to solve the problem in medium and large scale, four heuristic algorithms is proposed based on the Johnson’s algorithm. The numerical experiments are used to run the mathematical model and evaluate the performance of the proposed algorithms.

Genotoxic damage in auto body shop workers.

Science.gov (United States)

Siebel, Anna Maria; Basso da Silva, Luciano

2010-10-01

Some studies have shown increased DNA damage among car painters, but other professionals working in auto body and paint shops have not been extensively assessed. The aim of this study was to assess DNA damage in different types of auto body shop workers by measuring micronucleus (MN) levels in exfoliated buccal cells. The mean number of cells with MN per 2000 exfoliated buccal cells was analyzed in three groups of male workers: auto body repair technicians, painters, and office workers (control group). All participants answered a questionnaire inquiring about age, smoking habits, alcohol consumption, work practices, occupational exposure time, job activities, and use of protective equipment. The mean number of cells with MN was 3.50 ± 1.50 in auto body painters, 3.91 ± 2.10 in auto body repair technicians, and 0.80 ± 0.78 in office workers, with a significant difference between the control group and the two other groups (p = 0.0001). Age, occupational exposure time, use of protective masks, alcohol consumption, and smoking habit did not affect MN results. The findings indicate that technicians and painters working in auto body shops are at risk for genotoxic damage, while office workers seem to be protected.

Genetic algorithm parameters tuning for resource-constrained project scheduling problem

Science.gov (United States)

Tian, Xingke; Yuan, Shengrui

2018-04-01

Project Scheduling Problem (RCPSP) is a kind of important scheduling problem. To achieve a certain optimal goal such as the shortest duration, the smallest cost, the resource balance and so on, it is required to arrange the start and finish of all tasks under the condition of satisfying project timing constraints and resource constraints. In theory, the problem belongs to the NP-hard problem, and the model is abundant. Many combinatorial optimization problems are special cases of RCPSP, such as job shop scheduling, flow shop scheduling and so on. At present, the genetic algorithm (GA) has been used to deal with the classical RCPSP problem and achieved remarkable results. Vast scholars have also studied the improved genetic algorithm for the RCPSP problem, which makes it to solve the RCPSP problem more efficiently and accurately. However, for the selection of the main parameters of the genetic algorithm, there is no parameter optimization in these studies. Generally, we used the empirical method, but it cannot ensure to meet the optimal parameters. In this paper, the problem was carried out, which is the blind selection of parameters in the process of solving the RCPSP problem. We made sampling analysis, the establishment of proxy model and ultimately solved the optimal parameters.

Scheduling by positional completion times: analysis of a two-stage flow shop problem with a batching machine

NARCIS (Netherlands)

Hoogeveen, J.A.; Velde, van de S.L.

1998-01-01

We consider a scheduling problem introduced by Ahmadi et al., Batching and scheduling jobs on batch and discrete processors, Operation Research 40 (1992) 750–763, in which each job has to be prepared before it can be processed. The preparation is performed by a batching machine; it can prepare at

Análise de problemas de partição de instalações em sistemas job-shops por meio de modelos de redes de filas

Directory of Open Access Journals (Sweden)

Claudio Rogerio Negri da Silva

2007-08-01

Full Text Available Este artigo estuda o problema de projeto de fábrica focalizada envolvendo a partição da instalação (planta em subplantas e a alocação de capacidade em cada estação de trabalho das subplantas. O sistema de manufatura job-shop é representado por meio de uma rede de filas aberta genérica, e aproximações baseadas em métodos de decomposição são utilizadas para avaliar e otimizar o desempenho do sistema. O objetivo é reduzir a complexidade do sistema do ponto de vista da gestão do produto ou da gestão da estação, por exemplo, limitando-se a variância dos leadtimes dos produtos na rede. Apresenta-se um modelo de programação não-linear inteira para o problema e um algoritmo heurístico para resolvê-lo. Aplicando-se o algoritmo em alguns problemas testes, mostra-se que a partição da instalação em subplantas pode reduzir a variância dos leadtimes dos produtos na rede, sem necessidade de investimentos adicionais em capacidade. Além disso, algumas vezes é possível manter (ou até melhorar o desempenho da rede, particionando-a em subplantas que necessitam de menos capacidade do que a configuração original da rede como uma planta única.This paper studies the focused factory design involving the partition of the facility (plant into sub-plants and the allocation of capacity in each workstation of the sub-plants. The job-shop system is represented by a generic open queuing network and approximations based on decomposition methods are used to evaluate and optimize the performance of the system. The aim is to reduce the system complexity from the point of view of the product or workstation management, for example, limiting the variance of the product leadtimes in the network. An integer non-linear programming model and a heuristic algorithm are presented. Applying the algorithm to some testing problems, it is shown that the partition of the facility into sub-plants can reduce the variance of the product leadtimes without

A hybrid flow shop model for an ice cream production scheduling problem

Directory of Open Access Journals (Sweden)

Imma Ribas Vila

2009-07-01

Full Text Available Normal 0 21 false false false ES X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Taula normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} In this paper we address the scheduling problem that comes from an ice cream manufacturing company. This production system can be modelled as a three stage nowait hybrid flow shop with batch dependent setup costs. To contribute reducing the gap between theory and practice we have considered the real constraints and the criteria used by planners. The problem considered has been formulated as a mixed integer programming. Further, two competitive heuristic procedures have been developed and one of them will be proposed to schedule in the ice cream factory.

Coffee Shop As a Media for Self-Actualization Today's Youth

Directory of Open Access Journals (Sweden)

Salendra Salendra

2014-07-01

Full Text Available Trends go to a coffee shop that is currently self-actualization can be a medium for today's youth. In this study, the author uses Dramaturgy Theory introduced by Erving Goffman 1955 in The Presentation of Self in Everyday Life.                This research methods using qualitative methodology and data collection technique was done by observation, interviews and  study by literature. Trends goes to coffee shop by teen nowdays be assumed as teen’s activity to follow modern life style and it does to complete needs of self actualization.             It was concluded that the phenomenon of teenage habit to go to the coffee shop is an adolescent self-actualization behaviors performed by following a growing trend. Dramaturgy Theory discusses the two sides of teenage life in self actualize, front stage of a teenager is a person who has wide connections and likes to follow the trend of going to the coffee shop, and the back stage of the teenager is the pupil / student in an educational institution and a child in a family whose primary job is to learn and serve the elderly.

Hybrid Discrete Differential Evolution Algorithm for Lot Splitting with Capacity Constraints in Flexible Job Scheduling

Directory of Open Access Journals (Sweden)

Xinli Xu

2013-01-01

Full Text Available A two-level batch chromosome coding scheme is proposed to solve the lot splitting problem with equipment capacity constraints in flexible job shop scheduling, which includes a lot splitting chromosome and a lot scheduling chromosome. To balance global search and local exploration of the differential evolution algorithm, a hybrid discrete differential evolution algorithm (HDDE is presented, in which the local strategy with dynamic random searching based on the critical path and a random mutation operator is developed. The performance of HDDE was experimented with 14 benchmark problems and the practical dye vat scheduling problem. The simulation results showed that the proposed algorithm has the strong global search capability and can effectively solve the practical lot splitting problems with equipment capacity constraints.

At-Risk/Problematic Shopping and Gambling in Adolescence.

Science.gov (United States)

Yip, Sarah W; Mei, Songli; Pilver, Corey E; Steinberg, Marvin A; Rugle, Loreen J; Krishnan-Sarin, Suchitra; Hoff, Rani A; Potenza, Marc N

2015-12-01

Elevated levels of both pathological gambling (PG) and problem shopping (PS) have been reported among adolescents, and each is associated with a range of other negative health/functioning measures. However, relationships between PS and PG, particularly during adolescence, are not well understood. In this study, we explored the relationship between different levels of problem-gambling severity and health/functioning characteristics, gambling-related social experiences, gambling behaviors and motivations among adolescents with and without at-risk/problematic shopping (ARPS). Survey data from Connecticut high school students (n = 2,100) were analyzed using bivariate analyses and logistic regression modeling. Although at-risk/problematic gambling (ARPG) was not increased among adolescents with ARPS, adolescents with ARPG (vs non-gamblers) were more likely to report having experienced a growing tension or anxiety that could only be relieved by shopping and missing other obligations due to shopping. In comparison to the non-ARPS group, a smaller proportion of respondents in the ARPS group reported paid part-time employment, whereas a greater proportion of respondents reported excessive gambling by peers and feeling concerned over the gambling of a close family member. In general, similar associations between problem-gambling severity and measures of health/functioning and gambling-related behaviors and motivations were observed across ARPS and non-ARPS adolescents. However, associations were weaker among ARPS adolescents for several variables: engagement in extracurricular activities, alcohol and caffeine use and gambling for financial reasons. These findings suggest a complex relationship between problem-gambling severity and ARPS. They highlight the importance of considering co-occurring risk behaviors such as ARPS when treating adolescents with at-risk/problem gambling.

Análise de problemas de partição de instalações em sistemas job-shops por meio de modelos de redes de filas

OpenAIRE

Silva,Claudio Rogerio Negri da; Morabito,Reinaldo

2007-01-01

Este artigo estuda o problema de projeto de fábrica focalizada envolvendo a partição da instalação (planta) em subplantas e a alocação de capacidade em cada estação de trabalho das subplantas. O sistema de manufatura job-shop é representado por meio de uma rede de filas aberta genérica, e aproximações baseadas em métodos de decomposição são utilizadas para avaliar e otimizar o desempenho do sistema. O objetivo é reduzir a complexidade do sistema do ponto de vista da gestão do produto ou da ge...

A Hybrid Quantum Evolutionary Algorithm with Improved Decoding Scheme for a Robotic Flow Shop Scheduling Problem

Directory of Open Access Journals (Sweden)

Weidong Lei

2017-01-01

Full Text Available We aim at solving the cyclic scheduling problem with a single robot and flexible processing times in a robotic flow shop, which is a well-known optimization problem in advanced manufacturing systems. The objective of the problem is to find an optimal robot move sequence such that the throughput rate is maximized. We propose a hybrid algorithm based on the Quantum-Inspired Evolutionary Algorithm (QEA and genetic operators for solving the problem. The algorithm integrates three different decoding strategies to convert quantum individuals into robot move sequences. The Q-gate is applied to update the states of Q-bits in each individual. Besides, crossover and mutation operators with adaptive probabilities are used to increase the population diversity. A repairing procedure is proposed to deal with infeasible individuals. Comparison results on both benchmark and randomly generated instances demonstrate that the proposed algorithm is more effective in solving the studied problem in terms of solution quality and computational time.

Hygiene of work in main shops of modern coking by-product industry. [USSR

Energy Technology Data Exchange (ETDEWEB)

Kapitul' skii, V B

1984-07-01

The hygiene of working conditions is evaluated and compared for coking by-product industry shops using modern technology and machines with those using obsolete equipment and methods. Most basic factors in contamination of atmosphere of coking, pitch-coking and metal-refining shops are coal and coke dust, carbon monoxide and polycyclic aromatic hydrocarbons, especially carcinogenic benzpyrene. Contamination of air of working zone is determined by details of technology: periodicity or continuity of industrial processes, use of improved equipment for smokeless injection of charge into stoves and of hermetic pipes to remove gas with hydraulically operated caps, position of machines in shops and in coal tar distillation removal of carcinogenic benzpyrene by sulfonation and aeration. In modernized shops of coking by-product industry, illness and loss of work capacity are significantly lower than in plants using obsolete methods and equipment. Measures are presented for hygienic improvement of working conditions; both methods to further increase efficiency of technological processes and methods to protect individual worker on job such as use of respirators, protective clothing, plexiglass shields, shampoos and skin creams. 14 references.

Gold-decorated shopping centre; Golddekoriertes Shopping Center

Energy Technology Data Exchange (ETDEWEB)

Altmannshofer, Robert

2010-11-15

In the autumn 2009, the German quality seal sustainable construction for commercial new buildings was introduced. Thus, owners and operators of retail real estate and shopping centres can make clear their commitment in the matter of sustainability. The Ernst-August-Galerie (Hanover, Federal Republic of Germany) developed and operated by ECE Projektmanagement GmbH and Co. KG (Hamburg, Federal Republic of Germany) was a pilot project and also the first gold in one. With its around 150 shops, the Ernst-August-Galerie offers a supermarket, fashion outlets, a food court, service outlets and restaurants/cafes. The spacious and elegantly designed shopping mall with its piazzas and light-flooded rotundas exudes a Mediterranean air, making it a high-quality venue for shopping, strolling and leisure activities.

Um modelo de projeto de layout para ambientes job shop com alta variedade de peças baseado nos conceitos da produção enxuta A layout design model for job shop environments with high variety of parts based on lean production concepts

Directory of Open Access Journals (Sweden)

Alessandro Lucas da Silva

2012-01-01

, the study of layout concepts and the development of a layout design that aims at optimizing production are of crucial importance for production system improvement. Thus, this study presents a new layout design model of job shop environments with a high variety of parts. The model was developed as part of a PhD research project and was applied in some companies in the metal-mechanic sector. The results obtained showed the efficiency of the model developed. The purpose of the model is to lead the project team to develop layout alternatives that are consistent with the principles and concepts of lean production. It is worth mentioning again that the model was developed for environments with high variety of parts, and due to the difficulty in designing the layout in these environments, companies end up adopting the functional layout, a concept that presents serious problems such as excessive transport, high levels of in-process inventories, etc.

Coping in the World of Work. Practice in Problem Solving. Presentation Scripts. Filmstrip No. 1: Problems on the Job; and Filmstrip No. 2: Work Entry and Job Adjustment Problems.

Science.gov (United States)

Ohio State Univ., Columbus. Center for Vocational Education.

Presentation scripts for two sound filmstrips are contained in this document, which accompanies a career development unit on coping in the world of work designed to assist students in developing coping strategies to deal with work entry and job adjustment problems. (Other components of the unit--instructor's handbook, student guide, and…

Differential Validities for Shop Courses: Proposal B: Follow-Up of Subjects' Work Experiences. Final Report. Vol I: Procedures and Results.

Science.gov (United States)

Isabelle, L. A.; Lokan, J. J.

Follow-up information was collected on 1500 students who attended a two-year occupational high school, in order to relate predictor measures to success during training and subsequent job success. Although not predictive of dropouts, variables in the pre-test battery did predict performance in academic and shop courses; ratings of job success were…

Shopping for a safer car

Science.gov (United States)

2010-01-01

This brochure provides some helpful tips on what to look for when shopping for a safer car. Automakers are increasingly advertising the safety features of their cars. The problem is sorting out their claims and zeroing in on the safety features that ...

An Empirical Study Of Using New Technology like NFC, AI, RFID etc. to be implemented in shopping malls in ajmer : To Ease Out The Customer Shopping Experience Like Queue Less And Cashless Payment Mode

OpenAIRE

Dimple,; Jyoti Kushwah; Manisha Tak; Neeharika singh; Dr. Ajay Singh Jethoo; Vijay Laxmi Kalyani

2017-01-01

In today’s world due to rapid development of new shopping trend. The retailers launches new technologies for new shopping trend. In today scenario every people are busy. When we are talking about shopping from stores, shopping malls etc., the customers waiting in queue for long time for payment process. This is a problematic conditions for customers. The traditional shopping trend consuming more time of customers during shopping. To remove this problem many retailers are focussing that how to...

An Improved Multiobjective PSO for the Scheduling Problem of Panel Block Construction

Directory of Open Access Journals (Sweden)

Zhi Yang

2016-01-01

Full Text Available Uncertainty is common in ship construction. However, few studies have focused on scheduling problems under uncertainty in shipbuilding. This paper formulates the scheduling problem of panel block construction as a multiobjective fuzzy flow shop scheduling problem (FSSP with a fuzzy processing time, a fuzzy due date, and the just-in-time (JIT concept. An improved multiobjective particle swarm optimization called MOPSO-M is developed to solve the scheduling problem. MOPSO-M utilizes a ranked-order-value rule to convert the continuous position of particles into the discrete permutations of jobs, and an available mapping is employed to obtain the precedence-based permutation of the jobs. In addition, to improve the performance of MOPSO-M, archive maintenance is combined with global best position selection, and mutation and a velocity constriction mechanism are introduced into the algorithm. The feasibility and effectiveness of MOPSO-M are assessed in comparison with general MOPSO and nondominated sorting genetic algorithm-II (NSGA-II.

Relative performance of priority rules for hybrid flow shop scheduling with setup times

Directory of Open Access Journals (Sweden)

Helio Yochihiro Fuchigami

2015-12-01

Full Text Available This paper focuses the hybrid flow shop scheduling problem with explicit and sequence-independent setup times. This production environment is a multistage system with unidirectional flow of jobs, wherein each stage may contain multiple machines available for processing. The optimized measure was the total time to complete the schedule (makespan. The aim was to propose new priority rules to support the schedule and to evaluate their relative performance at the production system considered by the percentage of success, relative deviation, standard deviation of relative deviation, and average CPU time. Computational experiments have indicated that the rules using ascending order of the sum of processing and setup times of the first stage (SPT1 and SPT1_ERD performed better, reaching together more than 56% of success.

Significant Tasks in Training of Job-Shop Supervisors

Science.gov (United States)

Pederson, Leonard S.; Dresdow, Sally; Benson, Joy

2013-01-01

Purpose: The need for effective training of first-line supervisors is well established. Well-trained supervision is essential to our future as a country. A fundamental step in developing effective training is to develop a jobs needs assessment. In order to develop an effective needs assessment, it is necessary to know what the tasks are of…

Comparison Shopping Agents and Czech Online Customers’ Shopping Behaviour

Directory of Open Access Journals (Sweden)

Pilik Michal

2016-12-01

Full Text Available The internet has changed the lifestyles and shopping behaviours of customers. Online purchasing enables people to obtain information about products and services provided more effectively and easily, with the result that home shopping has become ordinary and usual. This paper presents part of a research focusing on online shopping customers’ behaviour in the Czech Republic. The article pertains to comparison shopping agents (CPAs, a tool which provides information to customers and helps find the best offer. The research was conducted on the basis of an online questionnaire available on an internet web page. The main results confirmed a dependency between online purchasing and the use of shopping agents, which are very popular in the Czech Republic. Almost two-thirds of online shoppers use CPAs when they engage in internet shopping. The final part of the paper addresses references and customers’ reviews as an important factor for the selection of online retailer.

Shopping Centres and Selected Aspects of Shopping Behaviour (Brno, the Czech Republic)

Czech Academy of Sciences Publication Activity Database

Kunc, J.; Tonev, P.; Szczyrba, Z.; Frantál, Bohumil

2012-01-01

Roč. 7, č. 2 (2012), s. 39-51 ISSN 2065-4421 Institutional support: RVO:68145535 Keywords : shopping centres * shopping habits * commuting to retail shops Subject RIV: AO - Sociology, Demography http://technicalgeography.org/pdf/2_2012/05_josef_kunc_petr_tonev_zdenek_szczyrba_bohumil_frantal_shopping_centres_and_selected_aspects_of_shopping_behaviour.pdf

Maximizing work integration in job placement of individuals facing mental health problems: Supervisor experiences.

Science.gov (United States)

Skarpaas, Lisebet Skeie; Ramvi, Ellen; Løvereide, Lise; Aas, Randi Wågø

2015-01-01

Many people confronting mental health problems are excluded from participation in paid work. Supervisor engagement is essential for successful job placement. To elicit supervisor perspectives on the challenges involved in fostering integration to support individuals with mental health problems (trainees) in their job placement at ordinary companies. Explorative, qualitative designed study with a phenomenological approach, based on semi-structured interviews with 15 supervisors involved in job placements for a total of 105 trainees (mean 7, min-max. 1-30, SD 8). Data were analysed using qualitative content analysis. Superviors experience two interrelated dilemmas concerning knowledge of the trainee and degree of preferential treatment. Challenges to obtaining successful integration were; motivational: 1) Supervisors previous experience with trainees encourages future engagement, 2) Developing a realistic picture of the situation, and 3) Disclosure and knowledge of mental health problems, and continuity challenges: 4) Sustaining trainee cooperation throughout the placement process, 5) Building and maintaining a good relationship between supervisor and trainee, and 6) Ensuring continuous cooperation with the social security system and other stakeholders. Supervisors experience relational dilemmas regarding pre-judgment, privacy and equality. Job placement seem to be maximized when the stakeholders are motivated and recognize that cooperation must be a continuous process.

PROPOSTA PARA IMPLANTAÇÃO DE BUSINESS INTELLIGENCE EM SHOPPING CENTER

Directory of Open Access Journals (Sweden)

Oswaldo Moreira Pereira

2016-06-01

Full Text Available The aim of the present job was to study the concepts involved in the business intelligence process to propose a solution that supports strategic decision with focus on shopping centers use. The BI technology proposed make use of SQL Server database and its tools that allows the multidimensional modeling, the transformation of data into strategic knowledge and the presentation of the results by the analytical processing information.

Uma propriedade estrutural do problema de programação da produção flow shop permutacional com tempos de setup

Directory of Open Access Journals (Sweden)

João Vitor Moccellin

2007-01-01

Full Text Available Neste artigo apresenta-se uma propriedade estrutural do problema de programação da produção flow shop permutacional com tempos de setup das máquinas separados dos tempos de processamento das tarefas, a qual foi identificada a partir de investigações que foram realizadas sobre as características do problema. Tal propriedade fornece um limitante superior do tempo de máquina parada entre a sua preparação e o início de execução das tarefas. Utilizando a propriedade, o problema original de programação da produção com minimização do makespan pode ser resolvido de maneira heurística por meio de uma analogia com o problema assimétrico do caixeiro-viajante.This paper deals with the permutation flow shop scheduling problem with separated machine setup times. As a result of an investigation on the problem characteristics a structural property is introduced. Such a property provides an upper bound on the idle time of the machines between the setup task and the job processing. As an application of this property, the original scheduling problem with the makespan criterion can be heuristically solved by an analogy with the asymmetric traveling salesman problem.

ShopComm: Community-Supported Online Shopping for Older Adults.

Science.gov (United States)

Gorkovenko, Katerina; Tigwell, Garreth W; Norrie, Christopher S; Waite, Miriam; Herron, Daniel

2017-01-01

The United Kingdom has an ageing population whose members experience significant life transitions as they grow older, for example, losing mobility due to deteriorating health. For these adults, digital technology has the potential to sustain their independence and improve their quality of life. However older adults can be reluctant to use digital solutions. In this paper, we review a local charity providing a grocery shopping service for older adults who are unable to go themselves. We explore how older adults perceive the benefits and drawbacks of both physical and digital shopping. Using these insights, we designed ShopComm to enable and support older adults with mobility impairments to shop online.

Omni channel fashion shopping

NARCIS (Netherlands)

Kemperman, A.D.A.M.; van Delft, L.; Borgers, A.W.J.; Pantano, E.

2015-01-01

This chapter gives insight into consumers' online and offline fashion shopping behavior, consumers' omni-channel usage during the shopping process, and consumer fashion shopper segments. Based on a literature review, omni-channel shopping behavior during the shopping process was operationalized.

ATTITUDES TOWARD ONLINE SHOPPING FROM THE ASPECTS OF PERSONAL CHARACTERISTICS AND SHOPPING MOTIVE THROUGH A DEVELOPING CONCEPT: PRIVATE SHOPPING

OpenAIRE

BAYBARS, Miray; USTUNDAGLI, Elif

2011-01-01

Private shopping is one of the concepts that serve as a members-only online shopping platform with deep discounts and well-known brands. The aim of this paper is to determine whether consumers’ need for uniqueness and innovativeness as a personal trait and price discount orientation affect consumer attitudes toward private shopping and their purchase decision or not. Research results revealed that need for uniqueness and innovativeness affect positive attitudes towards private shopping positi...

Job Flow Distribution and Ranked Jobs Scheduling in Grid Virtual Organizations

CERN Document Server

Toporkov, Victor; Tselishchev, Alexey; Yemelyanov, Dmitry; Potekhin, Petr

2015-01-01

In this work, we consider the problems of job flow distribution and ranked job framework forming within a model of cycle scheduling in Grid virtual organizations. The problem of job flow distribution is solved in terms of jobs and computing resource domains compatibility. A coefficient estimating such compatibility is introduced and studied experimentally. Two distribution strategies are suggested. Job framework forming is justified with such quality of service indicators as an average job execution time, a number of required scheduling cycles, and a number of job execution declines. Two methods for job selection and scheduling are proposed and compared: the first one is based on the knapsack problem solution, while the second one utilizes the mentioned compatibility coefficient. Along with these methods we present experimental results demonstrating the efficiency of proposed approaches and compare them with random job selection.

Supporting the Supermarket Shopping Experience through a Context-Aware Shopping Trolley

DEFF Research Database (Denmark)

Black, Darren; Clemmensen, Nils Jakob; Skov, Mikael B.

2009-01-01

Shopping in the real world is becoming an increasingly interactive experience as stores integrate various technologies to support shoppers. Based on an empirical study of supermarket shoppers, we designed a mobile context-aware system called the Context- Aware Shopping Trolley (CAST). The aim...... of the system is to support shopping in supermarkets through context-awareness and acquiring user attention. Thus, the interactive trolley guides and directs shoppers in the handling and finding of groceries. An empirical evaluation showed that shoppers using CAST adapted in different shopping behavior than...... traditional trolley shoppers by exhibiting a more uniform behavior in terms of product sequence collection and ease of finding products and thus, CAST supported the shopping experience....

Shopping online and/or in-store? A structural equation model of the relationships between e-shopping and in-store shopping

OpenAIRE

Farag, Sendy; Schwanen, Tim; Dijst, Martin

2005-01-01

Searching product information or buying goods online is becoming increasingly popular and could affect shopping trips. However, the relationship between e-shopping and in-store shopping is currently unclear. The aim of this study is to investigate empirically how the frequencies of online searching, online buying, and non-daily shopping trips relate to each other, after controlling for sociodemographic, land use, behavioral, and attitudinal characteristics. Data were collected from 826 respon...

Contributions of Self-Efficacy and Problem Solving Skills on Secretaries' Job Performance in Ogun State Public Service, Nigeria

Science.gov (United States)

Abosede, Subuola Catherine; Adesanya, Adebimpe Olusola

2017-01-01

This study is aimed at determining the contributions of self-efficacy and problem solving skills to the job performance of secretaries. The study also ascertained the relationship among self-efficacy, problem solving skills and job performance of the secretaries. The study employed the descriptive research design. Ten (10) secretaries were…

A novel particle swarm optimization algorithm for permutation flow-shop scheduling to minimize makespan

International Nuclear Information System (INIS)

Lian Zhigang; Gu Xingsheng; Jiao Bin

2008-01-01

It is well known that the flow-shop scheduling problem (FSSP) is a branch of production scheduling and is NP-hard. Now, many different approaches have been applied for permutation flow-shop scheduling to minimize makespan, but current algorithms even for moderate size problems cannot be solved to guarantee optimality. Some literatures searching PSO for continuous optimization problems are reported, but papers searching PSO for discrete scheduling problems are few. In this paper, according to the discrete characteristic of FSSP, a novel particle swarm optimization (NPSO) algorithm is presented and successfully applied to permutation flow-shop scheduling to minimize makespan. Computation experiments of seven representative instances (Taillard) based on practical data were made, and comparing the NPSO with standard GA, we obtain that the NPSO is clearly more efficacious than standard GA for FSSP to minimize makespan

Problem-Solving Management Training Effects on Sales Productivity and Job Satisfaction.

Science.gov (United States)

Ross, Paul C.; And Others

Research suggests that effective organizational change must be led by line personnel rather than by outside consultants. The Performance Management Program (PMP) implemented in two Bell Telephone companies is a line-led, self-help program in which managers participate in problem-solving activities within their own jobs. Marketing and sales…

Job Evaluation: Pay Equity Problem or Solution?

Science.gov (United States)

Mecham, Robert C.

It has been hypothesized that current methods of determining pay rates value the characteristics of jobs held primarily by men differently than the characteristics of jobs held primarily by women, resulting in lower earnings for women. A policy capturing approach using numerically rated job characteristics (PAQ data) was applied separately to the…

Internet Shopping

Institute of Scientific and Technical Information of China (English)

刘洪毓

2004-01-01

Nowadays you no longer need to walk round hundreds of shops looking for the items you need. You can shop for just about anything from your armchair. All you need is a computer and access(进入) to the Internet.

THE INFLUENCE OF HEDONIC SHOPPING MOTIVATION TO THE IMPULSE BUYING OF ONLINE-SHOPPING CONSUMER ON INSTAGRAM

Directory of Open Access Journals (Sweden)

Asnawati

2018-02-01

Full Text Available This research aims to know the influence of Adventure Shopping, Relaxation Shopping, Value Shopping, Social Shopping and Idea Shopping variables to the variable of Impulse Buying of Online-Shopping Consumer on Instagram. The type of the research is explanatory research. The result of F-test showed that Fcount (12.829 > Ftable (2.669 which meant that research variables had influences to the Impulse Buying. With partial correlation value of 0.548, Idea Shopping variable became the dominant factor influencing Impulse Buying on the online-shopping purchase on Instagram.

Heuristics for batching and sequencing in batch processing machines

Directory of Open Access Journals (Sweden)

Chuda Basnet

2016-12-01

Full Text Available In this paper, we discuss the “batch processing” problem, where there are multiple jobs to be processed in flow shops. These jobs can however be formed into batches and the number of jobs in a batch is limited by the capacity of the processing machines to accommodate the jobs. The processing time required by a batch in a machine is determined by the greatest processing time of the jobs included in the batch. Thus, the batch processing problem is a mix of batching and sequencing – the jobs need to be grouped into distinct batches, the batches then need to be sequenced through the flow shop. We apply certain newly developed heuristics to the problem and present computational results. The contributions of this paper are deriving a lower bound, and the heuristics developed and tested in this paper.

THE INFLUENCE OF HEDONIC SHOPPING MOTIVATION TO THE IMPULSE BUYING OF ONLINE-SHOPPING CONSUMER ON INSTAGRAM

OpenAIRE

Asnawati; Wahyuni S.

2018-01-01

This research aims to know the influence of Adventure Shopping, Relaxation Shopping, Value Shopping, Social Shopping and Idea Shopping variables to the variable of Impulse Buying of Online-Shopping Consumer on Instagram. The type of the research is explanatory research. The result of F-test showed that Fcount (12.829) > Ftable (2.669) which meant that research variables had influences to the Impulse Buying. With partial correlation value of 0.548, Idea Shopping variable became the dominant fa...

Shopping Malls - ShoppingCenters

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Collected from a variety of sources both commercial and internal, this layer represents shopping center locations within Volusia County and is maintained by the...

Female Consumers Recreational Shopping Experiences

Directory of Open Access Journals (Sweden)

Sarbjot Singh

2013-04-01

Full Text Available The study examines the core meaning of intrinsic shopping to understand their experimental aspects of recreational and leisure shopping. The study focus only on female shoppers of age group ranging from 25-30, and understand their mall experiences because this segment is newly transform into self dependent segment which have less social and familial liabilities and have enough enthusiasm to explore the world or their boundaries. The Grounded theory use for identification of recreational shopping themes which are (a seeking experiences and (b experimental shopping and each have respective sub themes. The themes are connected to the key idea that shoppers are motivated by their expectations and desires. The study uses social constructivism to find and understand the shopper meanings in real terms rather than imposing and judgment on them. The findings described the way people do recreational shopping and how shopping malls use as leisure space and become facilitators of recreational shopping activities. Females use malls to fulfill their recreational and leisure shopping experiences as this is the great way of enjoying shopping for females of small towns. In malls females not only enjoy product experiences but services experiences also which makes their shopping interesting. The way the female of this age category use malls help the marketers and retailers to understand this segment shopping patterns.

MODELING AND IMPLEMENTATION OF A DISTRIBUTED SHOP FLOOR MANAGEMENT AND CONTROL SYSTEM

Institute of Scientific and Technical Information of China (English)

无

2002-01-01

Adopting distributed control architecture is the important development direction for shop floor management and control system,is also the requirement of making it agile,intelligent and concurrent. Some key problems in achieving distributed control architecture are researched. An activity model of shop floor is presented as the requirement definition of the prototype system. The multi-agent based software architecture is constructed. How the core part in shop floor management and control system,production plan and scheduling is achieved. The cooperation of different agents is illustrated. Finally,the implementation of the prototype system is narrated.

Parallel genetic algorithms with migration for the hybrid flow shop scheduling problem

Directory of Open Access Journals (Sweden)

K. Belkadi

2006-01-01

Full Text Available This paper addresses scheduling problems in hybrid flow shop-like systems with a migration parallel genetic algorithm (PGA_MIG. This parallel genetic algorithm model allows genetic diversity by the application of selection and reproduction mechanisms nearer to nature. The space structure of the population is modified by dividing it into disjoined subpopulations. From time to time, individuals are exchanged between the different subpopulations (migration. Influence of parameters and dedicated strategies are studied. These parameters are the number of independent subpopulations, the interconnection topology between subpopulations, the choice/replacement strategy of the migrant individuals, and the migration frequency. A comparison between the sequential and parallel version of genetic algorithm (GA is provided. This comparison relates to the quality of the solution and the execution time of the two versions. The efficiency of the parallel model highly depends on the parameters and especially on the migration frequency. In the same way this parallel model gives a significant improvement of computational time if it is implemented on a parallel architecture which offers an acceptable number of processors (as many processors as subpopulations.

Batch Scheduling for Hybrid Assembly Differentiation Flow Shop to Minimize Total Actual Flow Time

Science.gov (United States)

Maulidya, R.; Suprayogi; Wangsaputra, R.; Halim, A. H.

2018-03-01

A hybrid assembly differentiation flow shop is a three-stage flow shop consisting of Machining, Assembly and Differentiation Stages and producing different types of products. In the machining stage, parts are processed in batches on different (unrelated) machines. In the assembly stage, each part of the different parts is assembled into an assembly product. Finally, the assembled products will further be processed into different types of final products in the differentiation stage. In this paper, we develop a batch scheduling model for a hybrid assembly differentiation flow shop to minimize the total actual flow time defined as the total times part spent in the shop floor from the arrival times until its due date. We also proposed a heuristic algorithm for solving the problems. The proposed algorithm is tested using a set of hypothetic data. The solution shows that the algorithm can solve the problems effectively.

Online Shopping Behavior

OpenAIRE

Shahzad, Hashim

2015-01-01

Online shopping is a very much developed phenomena in Scandinavian countries. Different online factors impact online consumers’ behavior differently depending on the environment of different regions. Sweden is one of the developed and technologically advanced countries. To see the impact of different factors on consumers’ online shopping behavior, the purpose of this study is to analyse the factors that influence consumers’ online shopping behavior in Sweden’s context. One of the objectives o...

Neural nets for job-shop scheduling, will they do the job?

NARCIS (Netherlands)

Rooda, J.E.; Willems, T.M.; Goodwin, G.C.; Evans, R.J.

1993-01-01

A neural net structure has been developed which is capable of solving deterministic jobshop scheduling problems, part of the large class of np-complete problems. The problem was translated in an integer linear-programming format which facilitated translation in an adequate neural net structure. Use

A hybrid quantum-inspired genetic algorithm for multiobjective flow shop scheduling.

Science.gov (United States)

Li, Bin-Bin; Wang, Ling

2007-06-01

This paper proposes a hybrid quantum-inspired genetic algorithm (HQGA) for the multiobjective flow shop scheduling problem (FSSP), which is a typical NP-hard combinatorial optimization problem with strong engineering backgrounds. On the one hand, a quantum-inspired GA (QGA) based on Q-bit representation is applied for exploration in the discrete 0-1 hyperspace by using the updating operator of quantum gate and genetic operators of Q-bit. Moreover, random-key representation is used to convert the Q-bit representation to job permutation for evaluating the objective values of the schedule solution. On the other hand, permutation-based GA (PGA) is applied for both performing exploration in permutation-based scheduling space and stressing exploitation for good schedule solutions. To evaluate solutions in multiobjective sense, a randomly weighted linear-sum function is used in QGA, and a nondominated sorting technique including classification of Pareto fronts and fitness assignment is applied in PGA with regard to both proximity and diversity of solutions. To maintain the diversity of the population, two trimming techniques for population are proposed. The proposed HQGA is tested based on some multiobjective FSSPs. Simulation results and comparisons based on several performance metrics demonstrate the effectiveness of the proposed HQGA.

The households purchase behavior and visitors shopping – amusing centre Olympia

Directory of Open Access Journals (Sweden)

Miroslav Foret

2006-01-01

Full Text Available The first part of the paper is devoted to the problems of the households purchase behavior in the Czech Republic. The main part is based on own empirical results from own marketing research conducted in 2005–2006. The results concerns on influences of food-stuffs purchases, clothes and shoes purchases, household equipments purchases and differences among them. In the second part is presented increasing number of shopping – amusing centres in the Czech Republic. These trends are changing purchase behavior our consumers. In Spring 2006 was conducted own marketing research of visitors shopping – amusing centre Olympia in Brno Modřice. Some more detail results give their basic sociodemographic characteristics as well as shopping orientations. The purchase in the shopping – amusing centres is a part of the contemporary life style, leisure and amusement.

Customer experience with online shopping : what are the unique experiences customers seek from online shopping?

OpenAIRE

Jin, Daoyan

2013-01-01

Over the last decade, there has been a great change in consumers' shopping behavior along with technological change. Online shopping is the use of computer technology for better shopping performance. Retailers are busy in studying consumers' behavior to see their attitudes toward online shopping and to meet the demand of online shoppers. Due to my interest in online business, I have also decided to study about customers' attitudes toward online shopping and specifically regarding factors that...

GENDER AND SHOPPING BEHAVIOR OUTCOMES IN THE CONTEXT OF SHOPPING CENTERS

Directory of Open Access Journals (Sweden)

Ioana Nicoleta ABRUDAN

2016-09-01

Full Text Available Understanding consumer behavior can be divided into three parts: before visiting the stores or shopping centers, during the visit, and after. From the point of view of the final result intended by retailers, satisfying customers in terms of profitability, all three components are equally important. A relevant segmentation criterion for most products and stores is gender. Previous research suggests that gender influences shopping motivations, the way people shop and shopping behavior outcomes. The purpose of this article is to investigate if there are, indeed, differences between shopping behavior outputs of women and men (affective loyalty (satisfaction and conative loyalty, as found by certain researchers, and also in terms of the factors that influence the formation of conative loyalty. The results confirm that there are few significant differences in the satisfaction level, although for women all values are slightly higher, and none in the repurchase and recommendation intentions between the two genders. Conative loyalty formation (defined as intent to repurchase and recommend takes place differently between the two genders.

Solar installer training: Home Builders Institute Job Corps

Energy Technology Data Exchange (ETDEWEB)

Hansen, K.; Mann, R. [San Diego Job Corps Center, Imperial Beach, CA (United States). Home Builders Inst.

1996-10-01

The instructors describe the solar installation training program operated since 1979 by the Home Builders Institute, the Educational Arm of the National Association of Home Builders for the US Department of Labor, Job Corps in San Diego, CA. The authors are the original instructors and have developed the program since its inception by a co-operative effort between the Solar Energy Industries Association, NAHB and US DOL. Case studies of a few of the 605 students who have gone to work over the years after the training are included. It is one of the most successful programs under the elaborate Student Performance Monitoring Information System used by all Job Corps programs. Job Corps is a federally funded residential job training program for low income persons 16--24 years of age. Discussion details the curriculum and methods used in the program including classroom, shop and community service projects. Solar technologies including all types of hot water heating, swimming pool and spa as well as photovoltaics are included.

Aportación de los sistemas de identificación automática a los entornos de fabricación Job-Shop : aplicación práctica en empresas de la construcción naval

OpenAIRE

Eguizabal Gandara, Luis Eduardo

2015-01-01

Esta tesis tiene por objeto el desarrollo de nuevas herramientas tecnológicas, para la mejora de los procesos de producción en talleres con configuración Job Shop. Este tipo de configuración se caracteriza por tener una fabricación intermitente, que en general, tiene peores rendimientos que la fabricación continua. Sin embargo, su gran ventaja es la versatilidad, que permite la fabricación de gran variedad de artículos y en series pequeñas. Es por ello, que es elegida por muchas empresas, com...

Intersections of discrimination due to unemployment and mental health problems: the role of double stigma for job- and help-seeking behaviors.

Science.gov (United States)

Staiger, Tobias; Waldmann, Tamara; Oexle, Nathalie; Wigand, Moritz; Rüsch, Nicolas

2018-05-21

The everyday lives of unemployed people with mental health problems can be affected by multiple discrimination, but studies about double stigma-an overlap of identities and experiences of discrimination-in this group are lacking. We therefore studied multiple discrimination among unemployed people with mental health problems and its consequences for job- and help-seeking behaviors. Everyday discrimination and attributions of discrimination to unemployment and/or to mental health problems were examined among 301 unemployed individuals with mental health problems. Job search self-efficacy, barriers to care, and perceived need for treatment were compared among four subgroups, depending on attributions of experienced discrimination to unemployment and to mental health problems (group i); neither to unemployment nor to mental health problems (group ii); mainly to unemployment (group iii); or mainly to mental health problems (group iv). In multiple regressions among all participants, higher levels of discrimination predicted reduced job search self-efficacy and higher barriers to care; and attributions of discrimination to unemployment were associated with increased barriers to care. In ANOVAs for subgroup comparisons, group i participants, who attributed discrimination to both unemployment and mental health problems, reported lower job search self-efficacy, more perceived stigma-related barriers to care and more need for treatment than group iii participants, as well as more stigma-related barriers to care than group iv. Multiple discrimination may affect job search and help-seeking among unemployed individuals with mental health problems. Interventions to reduce public stigma and to improve coping with multiple discrimination for this group should be developed.

Approximate models of job shops

OpenAIRE

Diamantidis, Alexandros

1999-01-01

Scheduling can be described as “the allocation of scarce resources over time to perform a collection of tasks”. They arise in many practical applications in manufacturing, marketing, service industries and within the operating systems of computers. Scheduling problems are frequently encountered in various activities of every day life. They exist whenever there is a choice o f the order in which a number of tasks can be performed Some examples are scheduling of classes in academic inst...

Online shopping hesitation.

Science.gov (United States)

Cho, Chang-Hoan; Kang, Jaewon; Cheon, Hongsik John

2006-06-01

This study was designed to understand which factors influence consumer hesitation or delay in online product purchases. The study examined four groups of variables (i.e., consumer characteristics, contextual factors perceived uncertainty factors, and medium/channel innovation factors) that predict three types of online shopping hesitation (i.e., overall hesitation, shopping cart abandonment, and hesitation at the final payment stage). We found that different sets of delay factors are related to different aspects of online shopping hesitation. The study concludes with suggestion for various delay-reduction devices to help consumers close their online decision hesitation.

The influences of social e-shopping in enhancing young women’s online shopping behaviour

OpenAIRE

Dennis, C; Morgan, A; Wright, LT; Jayawardhena, C

2010-01-01

Copyright @ 2010 Westburn Publishers Ltd The background to this paper is that shoppers, particularly women, are motivated by a variety of different reasons, including socialising and enjoyment. Despite the growth of Internet retailing (e-retailing), these social needs are largely unmet in e-shopping. In the high street, women do most of the shopping but online shopping (e-shopping) tends to be dominated by male shoppers. At the same time, social networking is growing fast and is especially...

Supporting shop floor intelligence

DEFF Research Database (Denmark)

Carstensen, Peter; Schmidt, Kjeld; Wiil, Uffe Kock

1999-01-01

Many manufacturing enterprises are now trying to introduce various forms of flexible work organizations on the shop floor. However, existing computer-based production planning and control systems pose severe obstacles for autonomous working groups and other kinds of shop floor control to become r......-to-day production planning by supporting intelligent and responsible workers in their situated coordination activities on the shop floor....

The effect of job organizational factors on job satisfaction in two automotive industries in Malaysia.

Science.gov (United States)

Dawal, Siti Zawiah Md; Taha, Zahari

2007-12-01

A methodology is developed in diagnosing the effect of job organizational factors on job satisfaction in two automotive industries in Malaysia. One hundred and seventy male subjects of age 18-40 years with the mean age of 26.8 and standard deviation (SD) of 5.3 years and the mean work experience of 6.5 years and SD of 4.9 years took part in the study. Five job organizational factors were tested in the study including job rotation, work method, training, problem solving and goal setting. A job organization questionnaire was designed and was based on respondents' perception in relation to job satisfaction. The results showed that job organization factors were significantly related to job satisfaction. Job rotation, work method, training and goal setting showed strong correlation with job satisfaction while problem solving had intermediate correlation in the first automotive industry. On the other hand, most job organization factors showed intermediate correlation with job satisfaction in the second automotive industry except the training factor which had low correlation with job satisfaction. These results highlight that job rotation, work methods, problem solving and goal setting are outstanding factors in the study of job satisfaction for automotive industries.

Binjai Shopping Mall : Arsitektur Metafora

OpenAIRE

Abadsyah, Haris

2014-01-01

City of Binjai have a potential to increase economic growth, especially in the field of trade and services.It can be seen from appearance of the commercial building like the shopping center ( Binjai Super Mall, Ramayana and Suzuya ) Construction of Binjai Shopping Mall intended for planning new shopping centers that provide public kebuthan in Binjai and well planned shopping center with optimal processing space and create a comfortable and pleasant atmosphere. In addition, the ...

The construction and evaluation of a scale of consumer shopping experience

Directory of Open Access Journals (Sweden)

B. A. Gillham

2003-10-01

Full Text Available Generally speaking consumer psychology have focused primarily on the problem solving and decision making processes underlying buying behaviour. As a result, the experience of consumers engaging in the activity of shopping has been neglected. The purpose of this study was to construct and evaluate a scale of consumer shopping experience. The instrument indicated that shopping experience is not merely a means to an end, but in many cases an end in itself. The Shopping Experience Survey consisting of 54 items was developed and administered to 426 respondents consisting of students at a large tertiary institution. The study indicated that the Shopping Experience Survey is highly reliable (rxx=0,965 and sensitive to group differences. Opsomming Benaderings tot verbruikersielkunde fokus in die algemeen hoofsaaklik op die probleemoplossings- en besluitnemingsprosesse onderliggend aan aankoopgedrag. Gevolglik het die ervarings wat verbruikers tydens die aankoopproses beleef, nie veel aandag geniet nie. Die doel van die onderhawige studie was om ’n skaal van verbruikeraankoopbelewenisse te konstrueer en te evalueer. Die instrument het aangedui dat die aankoopbelewenis nie ’n middel tot ’n doel is nie, maar ‘n doel insigself is. Die Shopping Experience Survey, bestaande uit 54 items, is ontwikkel en geadministreer aan 426 respondente van ’n groot residensiële tersiêre instelling. Met die studie is bevind dat die Shopping Experience Survey hoogs betroubaar is (rxx=0,965 en sensitief is vir groepverskille.

Introducing rapid diagnostic tests for malaria into registered drug shops in Uganda

DEFF Research Database (Denmark)

Mbonye, Anthony K; Clarke, Sîan E; Lal, Sham

2015-01-01

BACKGROUND: Malaria is a major public health problem in Uganda and the current policy recommends introduction of rapid diagnostic tests for malaria (RDTs) to facilitate effective case management. However, provision of RDTs in drug shops potentially raises a new set of issues, such as adherence...... to RDTs results, management of severe illnesses, referral of patients, and relationship with caretakers. The main objective of the study was to examine the impact of introducing RDTs in registered drug shops in Uganda and document lessons and policy implications for future scale-up of malaria control...... in the private health sector. METHODS: A cluster-randomized trial introducing RDTs into registered drug shops was implemented in central Uganda from October 2010 to July 2012. An evaluation was undertaken to assess the impact and the processes involved with the introduction of RDTs into drug shops, the lessons...

Consumers’ Attitude towards Online Shopping : Factors influencing Gotland consumers to shop online

OpenAIRE

Sultan, Muhammad Umar; Uddin, Md. Nasir

2011-01-01

In the era of globalization electronic marketing is a great revolution.  Over the last decade maximum business organizations are running with technological change.  Online shopping or marketing is the use of technology (i.e., computer) for better marketing performance. And retailers are devising strategies to meet the demand of online shoppers; they are busy in studying consumer behavior in the field of online shopping, to see the consumer attitudes towards online shopping. Therefore we have ...

Analysis of multi-stage open shop processing systems

NARCIS (Netherlands)

Eggermont, C.E.J.; Schrijver, A.; Woeginger, G.J.; Schwentick, T.; Dürr, C.

2011-01-01

We study algorithmic problems in multi-stage open shop processing systems that are centered around reachability and deadlock detection questions. We characterize safe and unsafe system states. We show that it is easy to recognize system states that can be reached from the initial state (where the

Integrated Job Scheduling and Network Routing

DEFF Research Database (Denmark)

Gamst, Mette; Pisinger, David

2013-01-01

We consider an integrated job scheduling and network routing problem which appears in Grid Computing and production planning. The problem is to schedule a number of jobs at a finite set of machines, such that the overall profit of the executed jobs is maximized. Each job demands a number of resou...... indicate that the algorithm can be used as an actual scheduling algorithm in the Grid or as a tool for analyzing Grid performance when adding extra machines or jobs. © 2012 Wiley Periodicals, Inc.......We consider an integrated job scheduling and network routing problem which appears in Grid Computing and production planning. The problem is to schedule a number of jobs at a finite set of machines, such that the overall profit of the executed jobs is maximized. Each job demands a number...... of resources which must be sent to the executing machine through a network with limited capacity. A job cannot start before all of its resources have arrived at the machine. The scheduling problem is formulated as a Mixed Integer Program (MIP) and proved to be NP-hard. An exact solution approach using Dantzig...

Estimation of distribution algorithm with path relinking for the blocking flow-shop scheduling problem

Science.gov (United States)

Shao, Zhongshi; Pi, Dechang; Shao, Weishi

2018-05-01

This article presents an effective estimation of distribution algorithm, named P-EDA, to solve the blocking flow-shop scheduling problem (BFSP) with the makespan criterion. In the P-EDA, a Nawaz-Enscore-Ham (NEH)-based heuristic and the random method are combined to generate the initial population. Based on several superior individuals provided by a modified linear rank selection, a probabilistic model is constructed to describe the probabilistic distribution of the promising solution space. The path relinking technique is incorporated into EDA to avoid blindness of the search and improve the convergence property. A modified referenced local search is designed to enhance the local exploitation. Moreover, a diversity-maintaining scheme is introduced into EDA to avoid deterioration of the population. Finally, the parameters of the proposed P-EDA are calibrated using a design of experiments approach. Simulation results and comparisons with some well-performing algorithms demonstrate the effectiveness of the P-EDA for solving BFSP.

Problems of job-profile for risk analysis

International Nuclear Information System (INIS)

Compes, P.C.

1984-01-01

There is no job-profile for the risk analyst. It would be his job to detect and classify accident risks, i.e. make a diagnosis and type rationalization, and to subsequently analyse them with respect to their frequency and probability as well as to the extent of damage caused. (DG) [de

Shopping in discount stores

DEFF Research Database (Denmark)

Zielke, Stephan

2014-01-01

quarters of intentions to shop in discount stores. Value perception has the strongest total effect, which is partly mediated by enjoyment, shame and guilt. Attributions influence the shopping intention indirectly via value perception and emotions. The inferior quality attribution has the strongest total......This paper analyzes the impact of price-related attributions, emotions and value perception on the intention to shop at grocery discounters in an integrated framework. Moderating effects of price consciousness are also analyzed. The results show that the proposed model explains almost three...... effect, followed by the efficiency of the business model attribution. The unfairness to stakeholders and the tricks in price communication attribution mostly influence the shopping intention for less price-conscious customers....

ROBUST-HYBRID GENETIC ALGORITHM FOR A FLOW-SHOP SCHEDULING PROBLEM (A Case Study at PT FSCM Manufacturing Indonesia

Directory of Open Access Journals (Sweden)

Johan Soewanda

2007-01-01

Full Text Available This paper discusses the application of Robust Hybrid Genetic Algorithm to solve a flow-shop scheduling problem. The proposed algorithm attempted to reach minimum makespan. PT. FSCM Manufacturing Indonesia Plant 4's case was used as a test case to evaluate the performance of the proposed algorithm. The proposed algorithm was compared to Ant Colony, Genetic-Tabu, Hybrid Genetic Algorithm, and the company's algorithm. We found that Robust Hybrid Genetic produces statistically better result than the company's, but the same as Ant Colony, Genetic-Tabu, and Hybrid Genetic. In addition, Robust Hybrid Genetic Algorithm required less computational time than Hybrid Genetic Algorithm

[Twisting and turning; the development of the Dutch science shops].

Science.gov (United States)

Lursen, M; Mulder, H; Lieshout, M

2000-01-01

The concept of science shops (Wetenschapswinkels) originates from the Netherlands. Science shops were based on the idea that universities had to play a more prominent role in the solution of social problems - an outcome of the discussion, initiated by students, on the democratisation of universities in the early 1970s. Starting as voluntary student organisations supported by individual staff members from the universities, they were devoted to give oppressed minority groups and the financially weak access to scientific research. Slowly, acknowledgement came. Science shops began to receive financial support from university boards. Support also came from the Dutch government. By now science shops have professionalized and most of them are well embedded in their universities. Many developments within society and the universities influenced the work and structure of the science shops. Positive developments were professionalization, growth, becoming embedded, and the introduction of new research themes. There were also negative developments, such as budget cuts and the fact that 'service to society' ceased to be a government objective for the universities. These led to recurring struggles for survival, which were not always won. Interest in the science shop concept has grown in other countries over the last years. In the 1980s, the system spread within Western Europe. Similar activities, based on the Dutch model, have started in North America and Eastern Europe in the 1990s. The activities on the international level led to an E.U. financial project to prepare an international network of science shops, which commenced in 1999. With information exchange and international cooperation as its major goals, the network will create new opportunties for the future.

Vape Shop Employees: Public Health Advocates?

OpenAIRE

Hart, Joy L; Walker, Kandi L; Sears, Clara G; Lee, Alexander S; Smith, Courteney; Siu, Allison; Keith, Rachel; Ridner, S. Lee

2017-01-01

INTRODUCTION E-cigarettes have increased in popularity and given rise to a new type of sales outlet?the vape shop. Expanding on work examining vape shop employee e-cigarette and tobacco attitudes and behaviors 1 , this study examined key messages that vape shop employees communicate to customers. METHODS Using informal interviews, observations, and a cross-sectional survey, we examined vape shop employees? (n=16) perceptions and e-cigarette use. Data were collected in nine vape shops in Louis...

Analyse af problemstillinger i moderne produktionssystemer ved hjælp af operationsanalytiske metoder

DEFF Research Database (Denmark)

Paulli, Jan

This PhD thesis consists of 6 volumes, the first being the above-mentioned Resumé. Vol. 2: Some Aspects of Applying Simulated Annealing and Tabu Search to the Quadratic Assignment Problem. Vol. 3: A Hierarchical Approach for the FMS Scheduling Problem Vol. 4: Solving the General Multiprocessor Job-shop...... Scheduling Problem (co-author: S. Dauzèrérès) Vol. 5: A Global Tabu Search Procedure for the General Multiprocessor Job-shop Scheduling Problem (co-author: S. Dauzère-Pérès) Vol. 6: Makespan Estimations in Flexible Manufacturing Systems (co-author: J.C. Fransoo, T.G. de Kok)...

An efficient genetic algorithm for a hybrid flow shop scheduling problem with time lags and sequence-dependent setup time

Directory of Open Access Journals (Sweden)

Farahmand-Mehr Mohammad

2014-01-01

Full Text Available In this paper, a hybrid flow shop scheduling problem with a new approach considering time lags and sequence-dependent setup time in realistic situations is presented. Since few works have been implemented in this field, the necessity of finding better solutions is a motivation to extend heuristic or meta-heuristic algorithms. This type of production system is found in industries such as food processing, chemical, textile, metallurgical, printed circuit board, and automobile manufacturing. A mixed integer linear programming (MILP model is proposed to minimize the makespan. Since this problem is known as NP-Hard class, a meta-heuristic algorithm, named Genetic Algorithm (GA, and three heuristic algorithms (Johnson, SPTCH and Palmer are proposed. Numerical experiments of different sizes are implemented to evaluate the performance of presented mathematical programming model and the designed GA in compare to heuristic algorithms and a benchmark algorithm. Computational results indicate that the designed GA can produce near optimal solutions in a short computational time for different size problems.

Emotional exhaustion and mental health problems among employees doing 'people work': the impact of job demands, job resources, and family-to-work conflict

NARCIS (Netherlands)

van Daalen, G.; van Daalen, Geertje; Sanders, Karin; Willemsen, Tineke M.; Veldhoven, Marc J.P.M.

2009-01-01

Objective: This study investigates the relationship between four job characteristics and family-to-work conflict on emotional exhaustion and mental health problems. Methods: Multiple regression analyses were performed using data from 1,008 mental health care employees. Separate regression analyses

Shopping with Acquired Brain Injuries, Coping Strategies and Maslowian Principles.

Science.gov (United States)

Andersson, Jonas E; Skehan, Terry; Rydén, Monica; Lagerkrans, Elisabeth

2016-01-01

A positive outcome of the modern welfare state is prolonged life expectancy. In Sweden, the expected life span has increased with approximatively 25 years during the 20th century [Statistics Sweden]. However, ageing is associated with an increased risk for acquiring cognitive and physical disabilities. This study is based on anonymized interviews with groups of older persons who experience cognitive problems and relatives. The interviewees were asked about everyday activities like shopping groceries, clothes or other necessities. The interviewees identified problems and described a series of strategies for coping. This paper uses fictionalized characters to present problems and coping strategies that the interviewees use to overcome cognitive challenges when shopping groceries. The strategies range from complete withdrawal, an increased dependency on proxies to the development of elaborate techniques to mask their problem and obtain assistance. Following the current trend in the design of the Swedish sales environment - large scale, abundance of goods and Maslowian strategies for making people stay longer (and spend more money) - accessibility in the built environment is often an absent friend.

The Effects of Shopping Orientations, Consumer Innovativeness, Purchase Experience, and Gender on Intention to Shop for Fashion Products Online

Directory of Open Access Journals (Sweden)

Ratih Puspa Nirmala

2011-02-01

Full Text Available Nowadays, many fashion retailers or marketers use the power of internet to promote and sell their products. This research examines the effects of consumers’ shopping orientations (brand/fashion consciousness, shopping enjoyment, price consciousness, convenience/time consciousness, shopping confidence, in-home shopping tendency, consumer innovativeness, online purchase experience for fashion products, and gender on consumers’ intention to shop for fashion products online. Data were collected through online surveys from the population of internet users in Indonesia, aged between 15 and 30 years old (generation Y, who had bought or browsed fashion products through the internet (N=210. This research is a quantitative research which uses purposive sampling and multiple regression analysis. Results show that the effects of several shopping orientations (shopping enjoyment, price consciousness, in-home shopping tendency, consumer innovativeness, online purchase experience for fashion products, and gender, are significant on consumers’ intention to shop for fashion products online. Furthermore, gender is marginally significant related to consumers’ intention to shop for fashion products online. Surprisingly, women tend to have lower intentions to shop for fashion products online compared to men.

Location-Routing Problem with Simultaneous Home Delivery and Customer’s Pickup for City Distribution of Online Shopping Purchases

Directory of Open Access Journals (Sweden)

Lin Zhou

2016-08-01

Full Text Available With the increasing interest in online shopping, the Last Mile delivery is regarded as one of the most expensive and pollutive—and yet the least efficient—stages of the e-commerce supply chain. To address this challenge, a novel location-routing problem with simultaneous home delivery and customer’s pickup is proposed. This problem aims to build a more effective Last Mile distribution system by providing two kinds of service options when delivering packages to customers. To solve this specific problem, a hybrid evolution search algorithm by combining genetic algorithm (GA and local search (LS is presented. In this approach, a diverse population generation algorithm along with a two-phase solution initialization heuristic is first proposed to give high quality initial population. Then, advantaged solution representation, individual evaluation, crossover and mutation operations are designed to enhance the evolution and search efficiency. Computational experiments based on a large family of instances are conducted, and the results obtained indicate the validity of the proposed model and method.

Smuggling and cross border shopping of tobacco in Europe.

Science.gov (United States)

Joossens, L; Raw, M

1995-05-27

Governments have recently become concerned about cross border shopping and smuggling because it can decrease tax revenue. The tobacco industry predicted that, with the removal of border controls in the European Union, price differences between neighbouring countries would lead to a diversion of tobacco trade, legally and illegally, to countries with cheaper cigarettes. According to them this diversion would be through increased cross border shopping for personal consumption or through increased smuggling of cheap cigarettes from countries with low tax to countries with high tax, where cigarettes are more expensive. These arguments have been used to urge governments not to increase tax on tobacco products. The evidence suggests, however, that cross border shopping is not yet a problem in Europe and that smuggling is not of cheap cigarettes to expensive countries. Instead, more expensive "international" brands are smuggled into northern Europe and sold illegally on the streets of the cheaper countries of southern Europe.

A hybrid genetic algorithm for the distributed permutation flowshop scheduling problem

Directory of Open Access Journals (Sweden)

Jian Gao

2011-08-01

Full Text Available Distributed Permutation Flowshop Scheduling Problem (DPFSP is a newly proposed scheduling problem, which is a generalization of classical permutation flow shop scheduling problem. The DPFSP is NP-hard in general. It is in the early stages of studies on algorithms for solving this problem. In this paper, we propose a GA-based algorithm, denoted by GA_LS, for solving this problem with objective to minimize the maximum completion time. In the proposed GA_LS, crossover and mutation operators are designed to make it suitable for the representation of DPFSP solutions, where the set of partial job sequences is employed. Furthermore, GA_LS utilizes an efficient local search method to explore neighboring solutions. The local search method uses three proposed rules that move jobs within a factory or between two factories. Intensive experiments on the benchmark instances, extended from Taillard instances, are carried out. The results indicate that the proposed hybrid genetic algorithm can obtain better solutions than all the existing algorithms for the DPFSP, since it obtains better relative percentage deviation and differences of the results are also statistically significant. It is also seen that best-known solutions for most instances are updated by our algorithm. Moreover, we also show the efficiency of the GA_LS by comparing with similar genetic algorithms with the existing local search methods.

Online Shopping: Advantages over the Offline Alternative

OpenAIRE

Dr Joshua Chang

2003-01-01

The advent of the Internet as a shopping medium has enabled shoppers to gain shopping benefits such as convenience and time-saving, better information, and price savings. This paper aims to provide a better understanding of the benefits of Internet shopping by identifying and discussing the advantages of Internet shopping over traditional storefront shopping.

Apprenticeship Learning: Learning to Schedule from Human Experts

Science.gov (United States)

2016-06-09

identified by the heuristic . A spectrum of problems (i.e. traveling salesman, job-shop scheduling, multi-vehicle routing) was represented , as task locations...caus- ing the codification of this knowledge to become labori- ous. We propose a new approach for capturing domain- expert heuristics through a...demonstrate that this approach accu- rately learns multi-faceted heuristics on both a synthetic data set incorporating job-shop scheduling and vehicle

The Accessibility in Shopping Centres: The Cases of Istanbul Profilo and Kozzy Malls

OpenAIRE

EVCİL, Ayse Nilay; YALÇIN USAL, S.Selhan

2014-01-01

Shopping centres are public areas which were used by people from every social strata and different age groups for consuming commodities or leisure. The aim of this study is to emphasize not only public areas accessibility of shopping centres but also consider interior space characteristics in terms of accessibility. The study showed that architectural design and interior design solutions were not sufficient to solve accessibility problem without active audit mechanism.

PENGARUH ATMOSFER PUSAT BELANJA PADA SHOPPING VALUE

Directory of Open Access Journals (Sweden)

Astrid Kusumowidagdo

2015-11-01

Full Text Available AbstractAt the moment, the creation of shopping environment design that provides certain sensation and experience become strategy of the shopping center. This research aims to find out about the influence of shopping center’s atmosphere towards shopping value. The formative factors of shopping centre’s atmosphere are architectural features, interior features and support facilities. The research begins with a focus group to adjust the indicators of the previous research to the present research’s object. The next stage of research is done with a multiple regression analysis. The research object is the atmosphere condition of Senayan City shopping center in Jakarta and the subjects are samples totaling to sixty people. The samples are visitors from the middle-class segment between the age of 18-35.The research finds that architectural features, interior features and support facilities collectively bring an influence towards shopping value in Senayan City Pusat belanja, wether partially, only interior features show the significant influence towards shopping value.Keywords: design, atmosphere, shopping centre, shopping value.AbstrakSaat ini penciptaan lingkungan belanja dengan yang memberikan sensasi dan pengalaman telah menjadi bagian dari strategi bisnis pusat belanja. Penelitian ini bertujuan untuk menelusuri pengaruh atmosfer pusat belanja terhadap shopping value. Atmosfer pusat belanja dibentuk oleh faktor-faktor yaitu fitur arsitektur, fitur interior dan fasilitas penunjang. Penelitian ini diawali dengan focus group untuk penentuan indikator yang tepat dan dilanjutkan dengan survey pada 60 orang dengan usia 18-35 tahun yang bersegmen menengah. Obyek penelitian adalahatmosfer dari pusat belanja Senayan City. Hasil penelitian menunjukkan terdapat hubungan dari faktor-faktor atmosfer pusat belanja secara serempak pada shopping value, sedangkan secara parsial hanya fitur interior yang memberikan pengaruh signifikan pada shopping value

Research and Applications of Shop Scheduling Based on Genetic Algorithms

Directory of Open Access Journals (Sweden)

Hang ZHAO

Full Text Available ABSTRACT Shop Scheduling is an important factor affecting the efficiency of production, efficient scheduling method and a research and application for optimization technology play an important role for manufacturing enterprises to improve production efficiency, reduce production costs and many other aspects. Existing studies have shown that improved genetic algorithm has solved the limitations that existed in the genetic algorithm, the objective function is able to meet customers' needs for shop scheduling, and the future research should focus on the combination of genetic algorithm with other optimized algorithms. In this paper, in order to overcome the shortcomings of early convergence of genetic algorithm and resolve local minimization problem in search process,aiming at mixed flow shop scheduling problem, an improved cyclic search genetic algorithm is put forward, and chromosome coding method and corresponding operation are given.The operation has the nature of inheriting the optimal individual ofthe previous generation and is able to avoid the emergence of local minimum, and cyclic and crossover operation and mutation operation can enhance the diversity of the population and then quickly get the optimal individual, and the effectiveness of the algorithm is validated. Experimental results show that the improved algorithm can well avoid the emergency of local minimum and is rapid in convergence.

Experience with Remote Job Execution

International Nuclear Information System (INIS)

Lynch, Vickie E.; Cobb, John W; Green, Mark L.; Kohl, James Arthur; Miller, Stephen D.; Ren, Shelly; Smith, Bradford C.; Vazhkudai, Sudharshan S.

2008-01-01

The Neutron Science Portal at Oak Ridge National Laboratory submits jobs to the TeraGrid for remote job execution. The TeraGrid is a network of high performance computers supported by the US National Science Foundation. There are eleven partner facilities with over a petaflop of peak computing performance and sixty petabytes of long-term storage. Globus is installed on a local machine and used for job submission. The graphical user interface is produced by java coding that reads an XML file. After submission, the status of the job is displayed in a Job Information Service window which queries globus for the status. The output folder produced in the scratch directory of the TeraGrid machine is returned to the portal with globus-url-copy command that uses the gridftp servers on the TeraGrid machines. This folder is copied from the stage-in directory of the community account to the user's results directory where the output can be plotted using the portal's visualization services. The primary problem with remote job execution is diagnosing execution problems. We have daily tests of submitting multiple remote jobs from the portal. When these jobs fail on a computer, it is difficult to diagnose the problem from the globus output. Successes and problems will be presented

RFID Data Cleaning for Shop Floor Applications

Science.gov (United States)

Ziekow, Holger; Ivantysynova, Lenka; Günter, Oliver

In several case studies we found that shop-floor applications in manufacturing pose special challenges to cleaning RFID data. The underlying problem in many scenarios is the uncertainty about the exact location of observed RFID tags. Simple filter s provided in common middleware solutions do not cope well with these challenges. Therefore we have developed an approach based on maximum-likelihood estimation to infer a tag's location within the reader range. This enables improved RFID data cleaning in a number of application scenarios. We stress the benefits of our approach along exemplary application scenarios that we found in manufacturing. In simulations and experiments with real world data we show that our approach outperforms existing solutions. Our approach can extend RFID middleware or reader firmware, to improve the use of RFID in a range of shop-floor applications.

Machine Shop Lathes.

Science.gov (United States)

Dunn, James

This guide, the second in a series of five machine shop curriculum manuals, was designed for use in machine shop courses in Oklahoma. The purpose of the manual is to equip students with basic knowledge and skills that will enable them to enter the machine trade at the machine-operator level. The curriculum is designed so that it can be used in…

Nurses’ Widespread Job Dissatisfaction, Burnout, And Frustration With Health Benefits Signal Problems For Patient Care

Science.gov (United States)

McHugh, Matthew D.; Kutney-Lee, Ann; Cimiotti, Jeannie P.; Sloane, Douglas M.; Aiken, Linda H.

2011-01-01

Job dissatisfaction among nurses contributes to costly labor disputes, turnover, and risk to patients. Examining survey data from 95,499 nurses, we found much higher job dissatisfaction and burnout among nurses who were directly caring for patients in hospitals and nursing homes than among nurses working in other jobs or settings, such as the pharmaceutical industry. Strikingly, nurses are particularly dissatisfied with their health benefits, which highlights the need for a benefits review to make nurses’ benefits more comparable to those of other white-collar employees. Patient satisfaction levels are lower in hospitals with more nurses who are dissatisfied or burned out—a finding that signals problems with quality of care. Improving nurses’ working conditions may improve both nurses’ and patients’ satisfaction as well as the quality of care. PMID:21289340

Nurses' widespread job dissatisfaction, burnout, and frustration with health benefits signal problems for patient care.

Science.gov (United States)

McHugh, Matthew D; Kutney-Lee, Ann; Cimiotti, Jeannie P; Sloane, Douglas M; Aiken, Linda H

2011-02-01

Job dissatisfaction among nurses contributes to costly labor disputes, turnover, and risk to patients. Examining survey data from 95,499 nurses, we found much higher job dissatisfaction and burnout among nurses who were directly caring for patients in hospitals and nursing homes than among nurses working in other jobs or settings, such as the pharmaceutical industry. Strikingly, nurses are particularly dissatisfied with their health benefits, which highlights the need for a benefits review to make nurses' benefits more comparable to those of other white-collar employees. Patient satisfaction levels are lower in hospitals with more nurses who are dissatisfied or burned out-a finding that signals problems with quality of care. Improving nurses' working conditions may improve both nurses' and patients' satisfaction as well as the quality of care.

PENERAPAN CUSTOMER RELATIONSHIP MANAGEMENT (CRM) BERBASIS SMS GATEWAY PADA ONLINE SHOP TOKOFARAH

OpenAIRE

Arfiani Nur Khusna

2016-01-01

SMS applications has become a promising business opportunities in the consumer and industrial markets in the world. One part that can not be separated from the SMS business is the role of an SMS Gateway, a system used by service providers to send and receive SMS automatically. Online shop tokofarah an online web business venture engaged in the production and sales of baby clothes and children. The problems that exist in the online shop tokofarah is the absence of communication between the cus...

The Accessibility in Shopping Centres: The Cases of Istanbul Profilo and Kozzy Malls

Directory of Open Access Journals (Sweden)

S.Selhan Yalçın Usal

2014-06-01

Full Text Available Shopping centres are public areas which were used by people from every social strata and different age groups for consuming commodities or leisure. The aim of this study is to emphasize not only public areas accessibility of shopping centres but also consider interior space characteristics in terms of accessibility. The study showed that architectural design and interior design solutions were not sufficient to solve accessibility problem without active audit mechanism.

Effect of Job Specialization on the Hospital Stay and Job Satisfaction of ED Nurses

OpenAIRE

Shamsi; Mahmoudi; Sirati Nir; Babatabar Darzi

2016-01-01

Background In recent decades, the increasing crowdedness of the emergency departments has posed various problems for patients and healthcare systems worldwide. These problems include prolonged hospital stay, patient dissatisfaction and nurse burnout or job dissatisfaction. Objectives The aim of this study was to investigate the effect of emergency department (ED) nurses’ job specialization on their job satisfaction and the length ...

Lower bounds for the head-body-tail problem on parallel machines: a computational study for the multiprocessor flow shop

NARCIS (Netherlands)

A. Vandevelde; J.A. Hoogeveen; C.A.J. Hurkens (Cor); J.K. Lenstra (Jan Karel)

2005-01-01

htmlabstractThe multiprocessor flow-shop is the generalization of the flow-shop in which each machine is replaced by a set of identical machines. As finding a minimum-length schedule is NP-hard, we set out to find good lower and upper bounds. The lower bounds are based on relaxation of the

Buying cannabis in 'coffee shops'.

Science.gov (United States)

Monshouwer, Karin; Van Laar, Margriet; Vollebergh, Wilma A

2011-03-01

The key objective of Dutch cannabis policy is to prevent and limit the risks of cannabis consumption for users, their direct environment and society ('harm reduction'). This paper will focus on the tolerated sale of cannabis in 'coffee shops'. We give a brief overview of Dutch policy on coffee shops, its history and recent developments. Furthermore, we present epidemiological data that may be indicative of the effects of the coffee shop policy on cannabis and other drug use. Dutch coffee shop policy has become more restrictive in recent years and the number of coffee shops has decreased. Cannabis prevalence rates in the adult population are somewhat below the European average; the rate is relatively high among adolescents; and age of first use appears to be low. On a European level, the use of hard drugs in both the Dutch adult and adolescent population is average to low (except for ecstasy among adults). International comparisons do not suggest a strong, upward effect of the coffee shop system on levels of cannabis use, although prevalence rates among Dutch adolescents give rise to concern. Furthermore, the coffee shop system appears to be successful in separating the hard and soft drugs markets. Nevertheless, in recent years, issues concerning the involvement of organised crime and the public nuisance related to drug tourism have given rise to several restrictive measures on the local level and have sparked a political debate on the reform of Dutch drug policy. © 2011 Trimbos Institute.

Kinect sensing of shopping related actions

NARCIS (Netherlands)

Popa, M.; Koc, A.K.; Rothkrantz, L.J.M.; Shan, C.; Wiggers, P.

2011-01-01

Surveillance systems in shopping malls or supermarkets are usually used for detecting abnormal behavior. We used the distributed video cameras system to design digital shopping assistants which assess the behavior of customers while shopping, detect when they need assistance, and offer their support

Environment-Aware Production Schedulingfor Paint Shops in Automobile Manufacturing: A Multi-Objective Optimization Approach.

Science.gov (United States)

Zhang, Rui

2017-12-25

The traditional way of scheduling production processes often focuses on profit-driven goals (such as cycle time or material cost) while tending to overlook the negative impacts of manufacturing activities on the environment in the form of carbon emissions and other undesirable by-products. To bridge the gap, this paper investigates an environment-aware production scheduling problem that arises from a typical paint shop in the automobile manufacturing industry. In the studied problem, an objective function is defined to minimize the emission of chemical pollutants caused by the cleaning of painting devices which must be performed each time before a color change occurs. Meanwhile, minimization of due date violations in the downstream assembly shop is also considered because the two shops are interrelated and connected by a limited-capacity buffer. First, we have developed a mixed-integer programming formulation to describe this bi-objective optimization problem. Then, to solve problems of practical size, we have proposed a novel multi-objective particle swarm optimization (MOPSO) algorithm characterized by problem-specific improvement strategies. A branch-and-bound algorithm is designed for accurately assessing the most promising solutions. Finally, extensive computational experiments have shown that the proposed MOPSO is able to match the solution quality of an exact solver on small instances and outperform two state-of-the-art multi-objective optimizers in literature on large instances with up to 200 cars.

Social Sustainability of Shopping Streets in Ankara

Directory of Open Access Journals (Sweden)

Özge YALÇINER ERCOŞKUN

2013-02-01

Full Text Available Shopping streets are integral parts of public spaces in traditional shopping areas of Central Business Districts (CBD. Furthermore, as modern shopping venues, shopping centers offer advantages for modern lifestyles with spacious shopping areas, variety of commercial and social activities, and economic value of their investments. These advantages act in favor of shopping centers and improve the level of shopping street social sustainability and its relevant concepts. The aim of this study is to analyze the main shopping streets of Ankara, using the concepts of social sustainability. In this study, these concepts, such as locality, identity, vitality, viability, sense of place, conviviality, meaning and local characteristics of the shopping streets are investigated. For the first time, the retail unit locations in Ankara, their brands and their business types, are illustrated on thematic land use maps using Geographical Information Systems (GIS software. Next, population activities and consumer spatial behavior are observed and marked on maps that are also referred to as social sustainability maps. The results of the study can be useful in formulating strategies within the framework of social sustainability, which is a relatively new concept.

Lower bounds for the head-body-tail problem on parallel machines : a computational study of the multiprocessor flow shop

NARCIS (Netherlands)

Vandevelde, A.; Hoogeveen, J.A.; Hurkens, C.A.J.; Lenstra, J.K.

2005-01-01

The multiprocessor flow-shop is the generalization of the flow-shop in which each machine is replaced by a set of identical machines. As finding a minimum-length schedule is NP-hard, we set out to find good lower and upper bounds. The lower bounds are based on relaxation of the capacities of all

Two-agent scheduling in open shops subject to machine availability and eligibility constraints

Directory of Open Access Journals (Sweden)

Ling-Huey Su

2015-09-01

Full Text Available Purpose: The aims of this article are to develop a new mathematical formulation and a new heuristic for the problem of preemptive two-agent scheduling in open shops subject to machine maintenance and eligibility constraints. Design/methodology: Using the ideas of minimum cost flow network and constraint programming, a heuristic and a network based linear programming are proposed to solve the problem. Findings: Computational experiments show that the heuristic generates a good quality schedule with a deviation of 0.25% on average from the optimum and the network based linear programming model can solve problems up to 110 jobs combined with 10 machines without considering the constraint that each operation can be processed on at most one machine at a time. In order to satisfy this constraint, a time consuming Constraint Programming is proposed. For n = 80 and m = 10, the average execution time for the combined models (linear programming model combined with Constraint programming exceeds two hours. Therefore, the heuristic algorithm we developed is very efficient and is in need. Practical implications: Its practical implication occurs in TFT-LCD and E-paper manufacturing wherein units go through a series of diagnostic tests that do not have to be performed in any specified order. Originality/value: The main contribution of the article is to split the time horizon into many time intervals and use the dispatching rule for each time interval in the heuristic algorithm, and also to combine the minimum cost flow network with the Constraint Programming to solve the problem optimally. 

Job and Work Design

OpenAIRE

Van den Broeck, Anja; Parker, Sharon K.

2017-01-01

Job design or work design refers to the content, structure, and organization of tasks and activities. It is mostly studied in terms of job characteristics, such as autonomy, workload, role problems, and feedback. Throughout history, job design has moved away from a sole focus on efficiency and productivity to more motivational job designs, including the social approach toward work, Herzberg’s two-factor model, Hackman and Oldham’s job characteristics model, the job demand control model of Kar...

Science Shops - a concept for community based learning

DEFF Research Database (Denmark)

Jørgensen, Michael Søgaard; Hende, Merete

2001-01-01

Experience from science shops show that besides assisting citizen groups, science shops can also contribute to the development of university curricula and research. The paper is based on an investigation of the impact of science shops on university curricula and research through a questionnaire...... sent out to science shops and through follow-up interviews with employees from nine different university based science shops. These science shops had in the questionnaire indicated that the science shop in one way or the other has had impact on university curricula and/or research. This paper focuses...... on the impact on university curricula. The case studies have been supplemented with articles and reports. The analysis has focused on the kind of impact, which the science shops have reported, and has tried to relate the impact to the local history of the science shop. One direct impact on the curricula...

Online Shopping In The UK

OpenAIRE

K. K. Ramachandran; K. K. Karthick; M. Saravana Kumar

2011-01-01

This paper will contribute to current academic literature in the area of online retailing and consumer behaviour. Our research outlines a survey conducted with respondents from the UK to ascertain their attitudes to grocery shopping both off and online. The findings indicate that, whilst the vast majority of our sample has experience of online shopping, few actively engage in online grocery shopping. Some of the reasons for this are highlighted and the key issues relate to consumer trust and ...

Shopping Online Sebagai Gaya Hidup

OpenAIRE

Lestari, Sri Budi

2015-01-01

The use of internet communication technology can make the world as if in one hand makes electronicbusiness with the concept of Online Shopping at its peak in recent years along with the development ofcommunication technologies over theInternet.How to shop online by using the internet through computers andmobile devices is increasingly popular smartphone can even be said to have become a trend today.Variousconvenience of shopping be the main thing to offer, with enough gadgets available in the...

Doctor shopping: a concept analysis.

Science.gov (United States)

Worley, Julie; Hall, Joanne M

2012-01-01

Prescription drug abuse is a significant problem in the United States that poses a serious health risk to Americans and is therefore significant to the field of nursing. The prescription drugs that are designated in the United States as having abuse potential are called controlled or scheduled drugs. The most common types of abused prescription drugs are benzodiazepines prescribed for anxiety, opioids prescribed for pain, and stimulants prescribed for attention deficit disorder. These prescription drugs are abused by taking larger doses than prescribed for nonmedical use to achieve a high or euphoric feeling, or are sold illicitly for profit. In 2009, there were 2.4 million nonmedical users of prescription opioids in the United States. These prescription drugs are often obtained by seeing multiple prescribers, often under false pretenses or with complicity from the prescribers that leads to abuse and illicit sales. The term doctor shopping has been used not only to refer to this phenomenon but has also had other meanings throughout the past decades. Thus, concept analysis is the focus of this article for clarification using the Walker and Avant method. Health implications and suggestions for minimizing doctor shopping are included.

An Enhanced Discrete Artificial Bee Colony Algorithm to Minimize the Total Flow Time in Permutation Flow Shop Scheduling with Limited Buffers

Directory of Open Access Journals (Sweden)

Guanlong Deng

2016-01-01

Full Text Available This paper presents an enhanced discrete artificial bee colony algorithm for minimizing the total flow time in the flow shop scheduling problem with buffer capacity. First, the solution in the algorithm is represented as discrete job permutation to directly convert to active schedule. Then, we present a simple and effective scheme called best insertion for the employed bee and onlooker bee and introduce a combined local search exploring both insertion and swap neighborhood. To validate the performance of the presented algorithm, a computational campaign is carried out on the Taillard benchmark instances, and computations and comparisons show that the proposed algorithm is not only capable of solving the benchmark set better than the existing discrete differential evolution algorithm and iterated greedy algorithm, but also capable of performing better than two recently proposed discrete artificial bee colony algorithms.

The Shopping Mall: A Teenager Hangout.

Science.gov (United States)

Anthony, Kathryn H.

1985-01-01

Investigated teenagers' use of the shopping mall as a "hangout" through interviews with 51 adolescents using the mall, and 10 hours of behavioral observations. Results indicated that many teenagers visit the shopping center regularly to watch members of the opposite sex, play video games, see friends, shop, and people-watch. (Author/NRB)

Cross-border shopping and tourism destination marketing

DEFF Research Database (Denmark)

Makkonen, Teemu

2016-01-01

This article addresses the economic impact that cross-border shopping has on the local tourism industry and the ways that cross-border shopping is taken advantage of in tourism destination marketing. Southern Jutland–situated in Denmark just north of the German border, where border shops situated......-border shopping into tourism destination marketing strategies. The results have wider relevance for other border regions.......This article addresses the economic impact that cross-border shopping has on the local tourism industry and the ways that cross-border shopping is taken advantage of in tourism destination marketing. Southern Jutland–situated in Denmark just north of the German border, where border shops situated...... just south of the same border enable Danes to capitalize on the lower value added tax levels in Germany–is utilized as an illustrative case example. The data was collected by analysing the relevant tourism destination marketing material and via interviews with local destination marketing organizations...

Preferences of men and women in the Czech Republic when shopping for food

Directory of Open Access Journals (Sweden)

Jana Turčínková

2012-01-01

Full Text Available Buying behavior of men and women shows considerable differences. The individual stages of purchase decision-making process lead to convergence or conversely deepening of these differences. The paper provides results of analysis of chosen aspects of consumer behavior of men and women in the Czech Republic. It focuses on the grocery shopping in small-sized shops. Due to the complexity of the problem the research could not cover all aspects associated with this topic. It identifies who in a household is responsible for grocery shopping, how often and in what quantity of purchases. The paper examines to what extent is a purchase planned and by what a consumer is usually stimulated to an impulsive shopping. Further, it describes factors leading to a choice of shopping place and to a satisfaction with shopping conditions. The primary data was collected through a method of in-depth interviews conducted from January to March 2011 on a sample of 56 respondents in the three smaller stores in the Moravské Budějovice, and via questionnaire survey which took place in all regions of the Czech Republic (n = 5809 among respondents aged 12+. The results confirmed we can observe differences in shopping behavior of women and man, even though the importance of various factors taken into account when making a choice of a particular food product show significant differences from the gender perspective (none of the analyzed factors was found to have higher statistical significance than weak, p < .05. The qualitative research, however, revealed that women tend to make more frequent purchases and keep a certain level of supplies at home, while men tend to leave shopping till it becomes necessary, they are more likely to stick to their shopping list and more loyal to their favorite products. Women are more flexible when in need to replace a missing product with its substitute. The proportion of impulsively purchased items in a shopping basket is higher for women than

Dynamic Support of Government in Online Shopping

OpenAIRE

Hai, Le Chi; Alam Kazmi, Syed Hasnain

2015-01-01

Advancements in online shopping for consumers requires consistent government support policies and the introduction of substantial government laws and regulations. In order to establish innovative developments in online shopping market environment that makes online shopping faster and stable, the government perspective is vital with the Technology Acceptance Model (TAM) for research and development in online shopping behavior for consumer’s confidence and their purchase intention. The proposed...

SHOPPING ONLINE SEBAGAI GAYA HIDUP

OpenAIRE

Sri Budi Lestari

2016-01-01

The use of internet communication technology can make the world as if in one hand makes electronic business with the concept of Online Shopping at its peak in recent years along with the development of communication technologies over theInternet.How to shop online by using the internet through computers and mobile devices is increasingly popular smartphone can even be said to have become a trend today.Various convenience of shopping be the main thing to offer, with enough gadgets ...

A new mathematical model for single machine batch scheduling problem for minimizing maximum lateness with deteriorating jobs

Directory of Open Access Journals (Sweden)

Ahmad Zeraatkar Moghaddam

2012-01-01

Full Text Available This paper presents a mathematical model for the problem of minimizing the maximum lateness on a single machine when the deteriorated jobs are delivered to each customer in various size batches. In reality, this issue may happen within a supply chain in which delivering goods to customers entails cost. Under such situation, keeping completed jobs to deliver in batches may result in reducing delivery costs. In literature review of batch scheduling, minimizing the maximum lateness is known as NP-Hard problem; therefore the present issue aiming at minimizing the costs of delivering, in addition to the aforementioned objective function, remains an NP-Hard problem. In order to solve the proposed model, a Simulation annealing meta-heuristic is used, where the parameters are calibrated by Taguchi approach and the results are compared to the global optimal values generated by Lingo 10 software. Furthermore, in order to check the efficiency of proposed method to solve larger scales of problem, a lower bound is generated. The results are also analyzed based on the effective factors of the problem. Computational study validates the efficiency and the accuracy of the presented model.

Process Waste Assessment - Paint Shop

International Nuclear Information System (INIS)

Phillips, N.M.

1993-06-01

This Process Waste Assessment was conducted to evaluate hazardous wastes generated in the Paint Shop, Building 913, Room 130. Special attention is given to waste streams generated by the spray painting process because it requires a number of steps for preparing, priming, and painting an object. Also, the spray paint booth covers the largest area in R-130. The largest and most costly waste stream to dispose of is open-quote Paint Shop wasteclose quotes -- a combination of paint cans, rags, sticks, filters, and paper containers. These items are compacted in 55-gallon drums and disposed of as solid hazardous waste. Recommendations are made for minimizing waste in the Paint Shop. Paint Shop personnel are very aware of the need to minimize hazardous wastes and are continuously looking for opportunities to do so

An Experimental Analysis on Dispatching Rules for the Train Platforming Problem in Busy Complex Passenger Stations

Directory of Open Access Journals (Sweden)

Qiongfang Zeng

2017-09-01

platforming problem (TPP by using mixed integer linear programming and job shop scheduling theory. First, the operation procedures and scheduled time adjustment costs of different train types specific to busy complex passenger stations are explicitly represented. Second, a multi-criteria scheduling model (MCS for TPP without earliness and tardiness time window (ETTW and a time window scheduling model (TWS with ETTW for TPP are proposed. Third, various dispatching rules were designed by incorporating the dispatcher experiences with modern scheduling theory and a rule-based metaheuristic to solve the above model is presented. With solution improvement strategies analogous to those used in practice by dispatchers, the realistic size problems in acceptable time can be solved.

A (Small) complexity performance contest: SPT versus LBFS

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

When discussing the nature of loading rules relevant to continuous dynamic job/flow shop systems, the general understanding is that results obtained in simpler structures of 2 to 4 machines are invariant to scaling and can be generalised without problems to more complex structures. The SPT...... results on pure re-entrant flow shop structures emerges. It now seems that alternative loading rules as for instance the LBFS (Last Buffer First Served) due to its strong long run stabilising property attracts quite some interest. To be more precise about the complexity aspect, complexity in job...... are not entirely only of theoretical interest, as well as results from a standard serial job/flow shop set-up, but with resource limitations that prevent the independent operations of the individual stations in the system....

A (Small) Complexity Performance Contest: SPT versus LBFS

DEFF Research Database (Denmark)

Nielsen, Erland Hejn

2002-01-01

When discussing the nature of loading rules relevant to continuous dynamic job/flow shop systems, the general understanding is that results obtained in simpler structures of 2 to 4 machines are invariant to scaling and can be generalised without problems to more complex structures. The SPT...... results on pure re-entrant flow shop structures emerges. It now seems that alternative loading rules as for instance the LBFS (Last Buffer First Served) due to its strong long run stabilising property attracts quite some interest. To be more precise about the complexity aspect, complexity in job...... are not entirely only of theoretical interest, as well as results from a standard serial job/flow shop set-up, but with resource limitations that prevent the independent operations of the individual stations in the system....

Ethical Ideologies: Do They Affect Shopping Behaviors and Perceptions of Morality?

Science.gov (United States)

Cho, Hyeon; Yoo, Jeong-Ju; Johnson, Kim K. P.

2005-01-01

Counterfeiting is a serious problem facing several industries, including the medical, agricultural, and apparel industries (Bloch, Bush, & Campbell, 1993). The authors investigated whether ethical viewpoints affect perceptions of the morality of particular shopping behaviors, attitudes toward counterfeit products, and intentions to purchase such…

Youth Clothes-Shopping Behavior: An Analysis by Gender.

Science.gov (United States)

Peters, John F.

1989-01-01

Explored possible gender differences in clothes-shopping behavior among adolescents. Findings from 387 college students revealed that: parents financially assisted sons and daughters equally; there was no gender difference in shopping frequency; mothers more frequently shopped with sons than with daughters; fathers rarely shopped with any…

Consumers preferences of shopping centers in Bratislava (Slovakia

Directory of Open Access Journals (Sweden)

Kristína Bilková

2016-05-01

Full Text Available There have been changes in the shopping behavior and preferences of consumers in the post-communist countries caused by political changes after 1989. Slovakia is not an exception, and it has been observed a change not only at the consumers’ level but also in retail stores. A notable bearer of such changes was the construction of big shopping centers that were a new phenomenon in shopping. They quickly became popular and changed spatial and shopping patterns of consumers. The main aim of this study is to analyze and evaluate the shopping preferences of consumers based on the example of the capital city – Bratislava (at the level of urban districts. The database consists of results of a questionnaire survey carried out in 2011. Respondents were interviewed inside the shopping center. The partial aims focus on the analysis of consumers’ perceptions, the frequency of their shopping and the mode of transport used for shopping. One of the goals of this study is also to evaluate the perception of consumers in terms of the catchment areas of the chosen shopping center, as well as the perceptional classification of retail in the given area and the accessibility of stores.

78 FR 13086 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Job Clubs...

Science.gov (United States)

2013-02-26

... church ministries; volunteer-run networking groups that meet at coffee shops or public libraries; and online networking sites such as LinkedIn. There have been past evaluations of the effects of job clubs... Policy, U.S. Department of Labor. [FR Doc. 2013-04391 Filed 2-25-13; 8:45 am] BILLING CODE 4510-23-P ...

Strategy of image management in retail shops

Directory of Open Access Journals (Sweden)

Sandra Soče Kraljević

2007-12-01

Full Text Available A sound positioning in consumers’ mind, along with strong promotion support, brought many retail shops to the top. This is mostly thanks to the image created in the consumers’ mind. A retail shop’s image may but need not conform to reality. Image often looks like a cliché. It overstates certain elements of the shop while simply omitting others. That is exactly why image is of great importance and often crucial to consumer behavior. This paper aims at determining the impact of image on customer behavior in the course of decision making about shopping and choosing a particular retail shop. Image is a significant factor of success of every company, hence also of a retail shops. It is a relatively strong value and a component of creating competitive advantage. But if we do not pay sufficient attention to image, it can become counterproductive. Instead to, like an additional value helps creating and maintaining the advantage in competition and realization of business aims, transforms into a limiting factor. Therefore, it is imperative to identify the elements of image that are of greatest importance to customers. Research has shown that customers choose the retail shop first and after that products and brands within this shop. When it comes to the supermarket, as a kind of retail shop, research has shown that two out of three shopping decisions are made by the customer on the spot, that is, without previous planning. That practically means that we can influence customers with different sales techniques. The paper suggests different strategies of image management for supermarkets and conventional shops. For supermarkets it is the “widest assortment” strategy, while for conventional shops the strategy is that of a “selected group of products“. Improvements to research methods will enable getting more information about customer behavior, while pressures of increased competition in the business environment will force retailers to get

CERN Shop - Christmas Sale in Bldg. 33

CERN Multimedia

PH Department

2010-01-01

Looking for Christmas present ideas? The CERN Shop will give CERN card holders a special reduction of 10 % on all CERN Shop articles from Monday 13.12.2010 to Saturday 18.12.2010. Come and visit the CERN Shop in the Reception Building 33.

Interviewing for a Job. The Wisconsin Guide to Local Curriculum Improvement in Industrial Education, K-12.

Science.gov (United States)

Ritz, John M.

The intent of this field tested instructional package is to provide the student with an overview of the management element of industry and how it relates to the duties of a shop foreman. Defining behavioral objectives, the course description includes an information section, classroom activities, sample job application forms, and student evaluation…

Marketing plan for a web shop business

OpenAIRE

Koskivaara, Leonilla

2014-01-01

Internet has changed the buying behavior of consumers during the past years and companies need to adapt to the changes. Web shop business is an important sales channel of today’s companies. Advantages of a web shop business include cost effectiveness and potential to do business globally. Challenges of a web shop business include search engine optimization and running both, a retail store and a web shop at the same time. Social media has become an important marketing channel and has bec...

Integrating job scheduling and constrained network routing

DEFF Research Database (Denmark)

Gamst, Mette

2010-01-01

This paper examines the NP-hard problem of scheduling jobs on resources such that the overall profit of executed jobs is maximized. Job demand must be sent through a constrained network to the resource before execution can begin. The problem has application in grid computing, where a number...

Job stress and occupational health

NARCIS (Netherlands)

Blanc, Le P.M.; Jonge, de J.; Schaufeli, W.B.; Chmiel, N.

2008-01-01

This chapter focuses on job stress in relation to workers’ physical and psycho logical health. We begin with an outline of job stress as a social problem, fol lowed by a discussion of the main perspectives on (job) stress, resulting in a process model of job stress that will be used as a frame of

CONGESTION AS A RESULT OF SCHOOL AND SHOPPING CENTER ACTIVITY

Directory of Open Access Journals (Sweden)

Meike Kumaat

2015-12-01

Full Text Available Development of land use in public facilities such as shopping center and school gives an impact on transportation problem in Manado City, North Sulawesi.  To determine factors which have causal relationship with congestion  as a result of school and shopping center activity then it need to be assessed and studied.  Descriptive study with observational survey was used in this study. The study ran Structural Equation Modelling (SEM by using AMOS program. Estimated method was used to calculate sample size then found 300 repondents, comprised : visitors and mall managers, school visitors, parents, school managers, Public Works department, and urban planning department .The study yielded a statistically significant correlation between  school and shopping center activity with congestion s. The result  indicated that school activity was positively related to congestion with p value  at p=0,000 (p ≤ 0,05. Shopping center activity was positively related to congestion with p value  at p=0,000 (p ≤ 0,05. The closer proximity from school to shooping center will causes severe traffic congestion. The relationship between school facility with proximity was found in p value at  p=0,000 (p ≤ 0,05 . The relationship between shopping center facility with proximity was found in p value at  p= 0,020 (p ≤ 0,05. While, the relationship between proximity with congestion was p= 0,008 (p ≤ 0,05. Monastery school and Mega Mall activity were affecting congestion because a closer proximity of two facilities. This indicates that the occurence of traffic congestion in Monastery School  may be dependent on existence of  Piere Tendean road link

Comparison of the risks of shopping behavior and opioid abuse between tapentadol and oxycodone and association of shopping behavior and opioid abuse.

Science.gov (United States)

Cepeda, M Soledad; Fife, Daniel; Kihm, Mary A; Mastrogiovanni, Greg; Yuan, Yingli

2014-12-01

This study compared the risks of opioid shopping behavior and opioid abuse between tapentadol immediate release and oxycodone immediate release and, to validate the definition of shopping, examined the association between opioid shopping and opioid abuse further. This retrospective cohort study using linked dispensing and diagnosis databases followed opioid-naive patients for development of shopping behavior and/or opioid abuse during 1 year after initial exposure to tapentadol or oxycodone. Shopping was defined by having overlapping opioid prescriptions from >1 prescriber filled at ≥3 pharmacies; abuse by having International Classification of Diseases, 9th revision diagnoses reflecting opioid abuse, addiction, or dependence. To determine their association, we cross-tabulated shopping and opioid abuse and calculated odds ratios. Risks of developing each outcome were estimated using logistic regression. Among 277,401 participants initiating opioid use with tapentadol (39,524) or oxycodone (237,877), 0.6% developed shopping behavior, 0.75% developed abuse. Higher proportions of patients in the oxycodone group developed shopping behavior and abuse than in the tapentadol group (shopping: adjusted odds ratio [95% confidence interval], 0.45 [0.36-0.55]; abuse: 0.44 [0.37-0.54]). Shopping behavior and abuse were associated; of those with shopping behavior, 6.5% had abuse. Age (18 to 64 y), sex (male), prior benzodiazepine use, paying cash, and history (mood disorders, abuse of nonopioid medications, and back pain) were risk factors for developing either outcome. Shopping behavior and abuse measure complementary, but associated, constructs, which further validates the current definition of shopping. The risk of developing either is lower among patients who initiate opioid use with tapentadol than those who initiate opioid use with oxycodone.

Shop stewards' learning and union strategies

DEFF Research Database (Denmark)

Warring, Niels

2007-01-01

In Denmark the trade unions have well established educational systems providing the shop stewards with a variety of competencies. Union courses have been analysed focusing on shop stewards' satisfaction with the content and the practical impact of the courses. However, little attention has been...... different theoretical traditions: Shop steward's learning is situational, relational and cross-contextual. Shop stewards' learning is lifelong and life wide. And shop stewards' learning is closely connected to the development of the labour market and not least the unions' priorities, interpretation...

Why do you shop there? A mixed methods study mapping household food shopping patterns onto weekly routines of black women.

Science.gov (United States)

DiSantis, Katherine Isselmann; Hillier, Amy; Holaday, Rio; Kumanyika, Shiriki

2016-01-28

The effectiveness of initiatives to increase healthy food access may be affected by where people decide to shop. People with poor neighborhood access to large grocery stores develop shopping patterns that require traveling to other areas, and some people who do have neighborhood access also travel elsewhere for food shopping. We sought to gain an understanding of household food shopping patterns in a sample of Black women in terms of where they shopped and why. All food shopping trips of 35 low- or middle/high-income black mothers or caregivers living with at least one child were identified from grocery shopping receipts collected over four consecutive weeks. Food shopping locations were mapped along with locations of participants' homes and other places they visited during weekly routine travels (e.g. work, child's school). Semi-structured individual interviews elicited narrative information about whether and how grocery shopping trips were linked to routine travels. Inductive content analysis was utilized to identify emergent themes from interviews. Themes were considered in relation to geospatial distances and travel patterns identified through mapping of participants' shopping. Participants shopped at an average of six different stores, traveling on average a total of 35 miles (sd = 41) (Euclidian distance) over the four weeks. The most frequented store was within a mile of home (57%) or home or another place visited in the weekly routine for about 77% of participants. Interview results emphasized the concept of convenience which referred to geographical proximity to the home or routine destinations and also to potential to save time because several stores were co-located or because the store layout was easy to navigate and familiar. Store selection also related to mode of transportation, pricing, and family preference for certain foods. People have specific reasons for consistently shopping in areas outside of their neighborhood of residence. Incorporating

Marketing activities of vape shops across racial/ethnic communities.

Science.gov (United States)

Garcίa, Robert; Sidhu, Anupreet; Allem, Jon-Patrick; Baezconde-Garbanati, Lourdes; Unger, Jennifer B; Sussman, Steve

2016-01-01

There has been a surge in the number of vape shops in the USA. Research on the marketing practices of e-cigarette manufacturers is scarce and even less known are the practices of vape shop retailers. Past research on tobacco marketing has shown differences in the amount and content of marketing material, based on a community's demographic profile. This study examined marketing strategies in vape shops and explored differences among vape shops located in communities that differ by ethnic composition. Data was gathered in 2014 from a pilot-study on vape shops (n=77) in Los Angeles, which documented the characteristics of shops through employee interviews and in-store observations. Data were collected from shops located in communities that were predominantly, African-American (n=20), Hispanic (n=17), Korean (n=18), or non-Hispanic White (n=22). Sixty-one percent of vape shops had advertisements (print ads and posters) for e-cigarettes and 84% offered discounts. Vape shops in Hispanic communities were more likely to have ethnic specific marketing material compared to shops in other communities. All the shops provided customers with free samples, however those in Korean and non-Hispanic White communities had a significantly higher prevalence of customer accessible free samples. Vape shop marketing practices differed by ethnic community. A large majority of shops provided free samples to their customers, a practice which is now banned by the FDA. It will be important to monitor how vape shops will adjust their marketing strategy because of this ban. Future research should expand on the findings presented here to provide regulators with further crucial information.

CERN Shop - Christmas Sale in Bldg. 33

CERN Multimedia

PH Department

Looking for Christmas present ideas? The CERN Shop will give the CERN card holders a special reduction of 10 % on all CERN Shop articles from Friday 11.12.2009 to Thursday 17.12.2009. Come to visit the CERN Shop at the Reception, Building 33. PH-EDU-PO

Security and Trustworthiness as Drivers of E-shop Competitiveness (Opinions of Young Customers

Directory of Open Access Journals (Sweden)

Petrtyl Jan

2012-03-01

Full Text Available Although the overall share of B2C e-commerce on the total retail turnover in the Czech Republic is low, e-shopping still indicates quite impressive year-to-year growth rates. Though very popular - especially in certain customer segments, such as young people - there are serious problems and challenges observed in this domain. Problems and challenges such as security and trustworthiness issues are often discussed and scrutinized. Thus, it is very important for both e-retailers and researchers to find out which factors drive e-shops’ competitiveness. In the introductory part, this paper presents useful and clear definitions to enlighten and clarify the topic. The description of Czech B2C e-commerce market follows, and it emphasizes the issues of ethics, security and trustworthiness and problems customers often face. Results of empirical research focused on issues on security and trustworthiness in relation to e-shop competitiveness are then presented and discussed. Suggestions for future research form the final part of the article.

OBSTACLES TO ONLINE SHOPPING: IMPACT OF GENDER AND INTERNET SECURITY ISSUES

Directory of Open Access Journals (Sweden)

AHU GENİS-GRUBER

2013-06-01

Full Text Available In the latest technology era, the widespread usage of internet enabled individuals to interact continuously and led to altered buying behavior patterns. Literature focuses on the critical effects in the field. Among many antecedents to online shopping, previous studies point out two important obstacles:  (i acceptance and tendency to use technology in accordance with gender perceptions and (ii internet security problems. This study analyzes the impact of these two prominent factors on e-commerce utilization by studying the effects of these factors through primary and secondary data; a survey designed specifically for this analysis and the cross-country data from Eurostat. The findings show that while internet security problems significantly impact online shopping behavior, the evidence is mixed for the impact of gender. The results of this paper provide insights for a successful e-commerce transaction and identify important obstacles to be avoided for an efficient e-commerce system.

Reflexivity in performative science shop projects

OpenAIRE

Beunen, R.; Duineveld, M.; During, R.; Straver, G.H.M.B.; Aalvanger, A.

2012-01-01

Science shop research projects offer possibilities for universities to engage with communities. Many science shop projects directly or indirectly intend to empower certain marginalised groups or interests within a decision-making process. In this article we argue that it is important to reflect on the role and position the researchers have in these projects. We present three science shop projects to illustrate some of the dilemmas that may arise in relation to citizen empowerment, democracy, ...

Dimensions of Consumer's Perceived Risk in Online Shopping

Institute of Scientific and Technical Information of China (English)

YE Naiyi

2004-01-01

Perceived risk is an important concept in consumer behavior in online shopping. It impedes the adopting online shopping. A structure model with seven factors of consumer's perceived risk in online shopping is developed in this paper. The results have the descriptive power about Chinese consumers' perceived risk in Internet shopping and provide framework for managerial use in China's e-commerce market environment.

The Effect of Job Satisfaction on Job Search: Not just whether, but also where

OpenAIRE

Josse Delfgaauw

2005-01-01

textabstractUsing survey data of public sector employees in the Netherlands, this paper shows that workers' satisfaction with various job domains not only affects whether but also where workers search for another job. An intuitive pattern emerges. Workers try to leave their current employer when their job search is instigated by dissatisfaction with an organisation-specific job domain, like management. Conversely, more job-specific problems, like a lack of autonomy, lead workers to opt for an...

Social image of students who shop and don't shop online.

Science.gov (United States)

Lammers, H Bruce; Curren, Mary T; Cours, Deborah; Lammers, Marilyn L

2003-06-01

A descriptive survey of a stratified random sample of 326 undergraduates from a large, diverse university in Los Angeles was conducted to assess whether resistance to online shopping might be, in part, related to negative social perceptions of those who shop online. Indirect questioning showed that students perceived online student shoppers as more lazy and less likely to fear for the safety and security of others but also as more trustworthy, attractive, successful, and smart. Differences in social perceptions were not related to these students' own online spending.

Rules for Adaptive Learning and Assistance on the Shop Floor

Science.gov (United States)

Ullrich, Carsten

2016-01-01

Today's shop floor, the area of a factory where operatives assemble products, is a complex and demanding work environment. The employed and produced technology becomes ever more complex, and employees are responsible for an increasing amount of tasks. As a consequence, the employee is under constant pressure to solve problems occurring on the shop…

INDONESIAN CUSTOMER SATISFACTION IN ONLINE SHOPPING TRADING

Directory of Open Access Journals (Sweden)

Hermawan F.

2018-03-01

Full Text Available This research aims to find out if the ease of shopping, site design, informative, comprehensive, and communication have a significant influence on the level of Indonesian customer satisfaction in online shopping transactions and how the impact to the word of mouth communication. Respondents of this study are the 250 students of Jakarta colleges. This study found that the variables of design, simplicity, and security have an influence on customer satisfaction in shopping online, while the informative variable and communication have no influence on the customer's satisfaction online shopping.

Space Odyssey Gift Shop

Science.gov (United States)

2000-01-01

The Space Odyssey Gift Shop located in StenniSphere at the John C. Stennis Space Center in Hancock County, Miss., offers every visitor the opportunity to go home with 'the right stuff' from his or her StenniSphere visit. The gift shop is located just inside the front doors to StenniSphere and offers a wide range of space-related apparel, memorabilia, toys, books, mission patches and more.

An AmI-Based Software Architecture Enabling Evolutionary Computation in Blended Commerce: The Shopping Plan Application

Directory of Open Access Journals (Sweden)

Giuseppe D’Aniello

2015-01-01

Full Text Available This work describes an approach to synergistically exploit ambient intelligence technologies, mobile devices, and evolutionary computation in order to support blended commerce or ubiquitous commerce scenarios. The work proposes a software architecture consisting of three main components: linked data for e-commerce, cloud-based services, and mobile apps. The three components implement a scenario where a shopping mall is presented as an intelligent environment in which customers use NFC capabilities of their smartphones in order to handle e-coupons produced, suggested, and consumed by the abovesaid environment. The main function of the intelligent environment is to help customers define shopping plans, which minimize the overall shopping cost by looking for best prices, discounts, and coupons. The paper proposes a genetic algorithm to find suboptimal solutions for the shopping plan problem in a highly dynamic context, where the final cost of a product for an individual customer is dependent on his previous purchases. In particular, the work provides details on the Shopping Plan software prototype and some experimentation results showing the overall performance of the genetic algorithm.

Determinants Of Online Shopping In Manado

OpenAIRE

Halim, Ellen

2013-01-01

Retailers utilize online media to reach more potential customers. Internet connects the retailer and customers without any geographic location boundaries. Internet growth has a positive impact for business world. There is a new shopping method in non-store shopping as people can buy products or services without having to travel to the outlets like traditional retail does. With the increase of online retailers on internet world, online shopping became popular. The objective of this research is...

Potential of Natural Ventilation in Shopping Centres

DEFF Research Database (Denmark)

Diederichsen, Alice; Friis, Kristina; Brohus, Henrik

2008-01-01

The indoor environmental quality (IEQ) is a fundamental requirement for a well performing shopping centre. This paper contains a pilot study of the potential of using hybrid ventilation (a combination of automatically controlled natural and mechanical ventilation - respectively NV and MV) in shop......The indoor environmental quality (IEQ) is a fundamental requirement for a well performing shopping centre. This paper contains a pilot study of the potential of using hybrid ventilation (a combination of automatically controlled natural and mechanical ventilation - respectively NV and MV......) in shopping centres with focus on both the achieved IEQ and energy consumptions for air movement. By thermal building simulations it is found that there exists an interesting potential for hybrid ventilation of shopping centres, which can lead to great savings in the electrical energy consumptions...

A Mathematical Model for Scheduling a Batch Processing Machine with Multiple Incompatible Job Families, Non-identical Job dimensions, Non-identical Job sizes, Non-agreeable release times and due dates

International Nuclear Information System (INIS)

Ramasubramaniam, M; Mathirajan, M

2013-01-01

The paper addresses the problem scheduling a batch processing machine with multiple incompatible job families, non-identical job dimensions, non-identical job sizes and non-agreeable release dates to minimize makespan. The research problem is solved by proposing a mixed integer programming model that appropriately takes into account the parameters considered in the problem. The proposed is validated using a numerical example. The experiment conducted show that the model can pose significant difficulties in solving the large scale instances. The paper concludes by giving the scope for future work and some alternative approaches one can use for solving these class of problems.

HESITANCY TOWARDS ONLINE SHOPPING, A STUDY OF PAKISTANI CONSUMERS

Directory of Open Access Journals (Sweden)

Usman YOUSAF

2012-01-01

Full Text Available To study the influence of Perceived cost, risk, convenience and enjoyment on online consumer purchases. Being more convenient online shopping seems painless compared to in store shopping, why consumers are still reluctant to shop online?.A sample of 220 questionnaires was filled from different departments at University of Sargodha. Respondents were asked to fill the questionnaire based on four factors (Perceived cost, Perceived risk, Perceived convenience, Perceived enjoyment, there were 2 general questions. Out of 220, 207 questionnaires were returned. One sample test is applied in this study to check the reliability of independent variables. Analysis was also done on basis of gender and their ages. The most important factor out of four, which can persuade the customer's online buying decision, is delivery cost for purchased items and it has negative relationship with dependent variable, moreover perceived risk has also negative relationship with dependent one. Perceived convenience and Perceived enjoyment has positive relationship with online shopping preference. As online shopping is easier to do but due to extra delivery cost and risk factors consumers do not adopt online shopping and these factors should be minimized to promote online shopping. Online shopping should be promoted and to gain the consumer confidence, delivery cost and risk factor should be minimized. As online shopping is easier to do as compared to offline shopping but people still reluctant to use internet for online shopping, so to promote online shopping delivery cost and risk factor should be minimized to gain consumers attraction and confidence. People want to experience online shopping but it won’t be promoted until delivery cost and perceived risk factors be reduced. A little work has been done on exploring the factors that influence the online buying decision. These factors are called situational factors and include delivery charges, risk factors, convenience

The "Shopping" Behavior of Parents of Mentally Retarded Children: The Professional Person's Role

Science.gov (United States)

Anderson, Kathryn A.

1971-01-01

Discussed is the role of the professional in preventing or stopping diagnostic and therapeutic shopping (repeated visits to the same or different professionals without resolution of a resolvable problem), with emphasis on the initial informing interview. (KW)

Commuter Shopping : A study in understanding commuting in the context of shopping

OpenAIRE

Andersson, Åsa; Skoog, Sara; Svensson, Johanna

2014-01-01

Background For ages people have commuted to work, or to other activities, located outside their home municipality. Statements found indicate that the basic decision for commuting are based on utility maximisation and no matter what the character of the benefit is; it should be higher than what can be found closer to the home location. This thesis aims to investigate if people are also commuting with the purpose of obtaining benefits from shopping. The shopping location will in this thesis be ...

Retail Shopping Lists

DEFF Research Database (Denmark)

Schmidt, Marcus

2012-01-01

categories. An association between the frequency of a brand's appearance on lists and the amount of money spent on advertising the brand could not be found. A strong link between brands, prices and store names is revealed. Price in the majority of cases refers to brands rather than to product categories......The paper addresses consumers' shopping lists. The current study is based on a survey of 871 lists collected at retail grocery stores. Most items on shopping lists appear on the product category level rather than the brand level. The importance of the brand level varies considerably across product...

The Bergen Shopping Addiction Scale: reliability and validity of a brief screening test

Science.gov (United States)

Andreassen, Cecilie S.; Griffiths, Mark D.; Pallesen, Ståle; Bilder, Robert M.; Torsheim, Torbjørn; Aboujaoude, Elias

2015-01-01

Although excessive and compulsive shopping has been increasingly placed within the behavioral addiction paradigm in recent years, items in existing screens arguably do not assess the core criteria and components of addiction. To date, assessment screens for shopping disorders have primarily been rooted within the impulse-control or obsessive-compulsive disorder paradigms. Furthermore, existing screens use the terms ‘shopping,’ ‘buying,’ and ‘spending’ interchangeably, and do not necessarily reflect contemporary shopping habits. Consequently, a new screening tool for assessing shopping addiction was developed. Initially, 28 items, four for each of seven addiction criteria (salience, mood modification, conflict, tolerance, withdrawal, relapse, and problems), were constructed. These items and validated scales (i.e., Compulsive Buying Measurement Scale, Mini-International Personality Item Pool, Hospital Anxiety and Depression Scale, Rosenberg Self-Esteem Scale) were then administered to 23,537 participants (Mage = 35.8 years, SDage = 13.3). The highest loading item from each set of four pooled items reflecting the seven addiction criteria were retained in the final scale, The Bergen Shopping Addiction Scale (BSAS). The factor structure of the BSAS was good (RMSEA = 0.064, CFI = 0.983, TLI = 0.973) and coefficient alpha was 0.87. The scores on the BSAS converged with scores on the Compulsive Buying Measurement Scale (CBMS; 0.80), and were positively correlated with extroversion and neuroticism, and negatively with conscientiousness, agreeableness, and intellect/imagination. The scores of the BSAS were positively associated with anxiety, depression, and low self-esteem and inversely related to age. Females scored higher than males on the BSAS. The BSAS is the first scale to fully embed shopping addiction within an addiction paradigm. A recommended cutoff score for the new scale and future research directions are discussed. PMID:26441749

The Bergen Shopping Addiction Scale: reliability and validity of a brief screening test.

Science.gov (United States)

Andreassen, Cecilie S; Griffiths, Mark D; Pallesen, Ståle; Bilder, Robert M; Torsheim, Torbjørn; Aboujaoude, Elias

2015-01-01

Although excessive and compulsive shopping has been increasingly placed within the behavioral addiction paradigm in recent years, items in existing screens arguably do not assess the core criteria and components of addiction. To date, assessment screens for shopping disorders have primarily been rooted within the impulse-control or obsessive-compulsive disorder paradigms. Furthermore, existing screens use the terms 'shopping,' 'buying,' and 'spending' interchangeably, and do not necessarily reflect contemporary shopping habits. Consequently, a new screening tool for assessing shopping addiction was developed. Initially, 28 items, four for each of seven addiction criteria (salience, mood modification, conflict, tolerance, withdrawal, relapse, and problems), were constructed. These items and validated scales (i.e., Compulsive Buying Measurement Scale, Mini-International Personality Item Pool, Hospital Anxiety and Depression Scale, Rosenberg Self-Esteem Scale) were then administered to 23,537 participants (M age = 35.8 years, SD age = 13.3). The highest loading item from each set of four pooled items reflecting the seven addiction criteria were retained in the final scale, The Bergen Shopping Addiction Scale (BSAS). The factor structure of the BSAS was good (RMSEA = 0.064, CFI = 0.983, TLI = 0.973) and coefficient alpha was 0.87. The scores on the BSAS converged with scores on the Compulsive Buying Measurement Scale (CBMS; 0.80), and were positively correlated with extroversion and neuroticism, and negatively with conscientiousness, agreeableness, and intellect/imagination. The scores of the BSAS were positively associated with anxiety, depression, and low self-esteem and inversely related to age. Females scored higher than males on the BSAS. The BSAS is the first scale to fully embed shopping addiction within an addiction paradigm. A recommended cutoff score for the new scale and future research directions are discussed.

Growing Shopping Malls and Behavior of Urban Shoppers

OpenAIRE

Rajagopal

2009-01-01

Shopping malls contribute to business more significantly than traditional markets which were viewed as simple convergence of supply and demand. Shopping malls attract buyers and sellers, and induce customers providing enough time to make choices as well as a recreational means of shopping. However, competition between malls, congestion of markets and traditional shopping centers has led mall developers and management to consider alternative methods to build excitement with customers. This stu...

Designing electronic shops, persuading consumers to buy

DEFF Research Database (Denmark)

Dormann, Claire

2000-01-01

The purpose of this article is to show how to design persuasive and successful Web shops. An approach to commercial site design that draws on theories of visual persuasion is proposed. We focus on the role of emotion. Images in an ad are typically meant to create some emotional disposition toward....... To strengthen the discussion, an evaluation of shop home pages, situated within the perspective of visual persuasion is presented. This study has given some indications that viewers form distinctive emotional impressions from shop designs. Thus, by building on visual persuasion theories, we can learn how...... to design seductive Web shops....

Enhancing Older People’s Outdoor Activities Through User-Centered (Shopping Bag Product Design; A Qualitative Study Based on the User-Centered Approach

Directory of Open Access Journals (Sweden)

Maliheh Naeimi

2015-07-01

Conclusion Considering the elderly's problems in shopping, a solution in product design is proposed to facilitate shopping and prevent difficulties such as forgetfulness. In future studies considering the anthropometrical measures to adjust the proposed solutions with the specific needs of users is suggested.

CONWIP card setting in a flow-shop system with a batch production machine

Directory of Open Access Journals (Sweden)

Marcello Braglia

2011-01-01

Full Text Available This paper presents an analytical technique to determine the optimum number of cards to control material release in a CONWIP system. The work focuses on the card setting problem for a flow-shop system characterised by the presence of a batch processing machine (e.g. a kiln for long heat treatment. To control production, two different static approaches are developed: the first one is used when the bottleneck coincides with the batch processing machine and the second one is proposed when the bottleneck is another machine of the flow shop. In both contexts, by means of the appropriate model, one can optimize the performance of the flow-shop by maximizing the throughput and keeping the work in process at a minimum level. Numerical examples are also included in the paper to confirm the validity of the models and to demonstrate their practical utility.

Discrete harmony search algorithm for scheduling and rescheduling the reprocessing problems in remanufacturing: a case study

Science.gov (United States)

Gao, Kaizhou; Wang, Ling; Luo, Jianping; Jiang, Hua; Sadollah, Ali; Pan, Quanke

2018-06-01

In this article, scheduling and rescheduling problems with increasing processing time and new job insertion are studied for reprocessing problems in the remanufacturing process. To handle the unpredictability of reprocessing time, an experience-based strategy is used. Rescheduling strategies are applied for considering the effect of increasing reprocessing time and the new subassembly insertion. To optimize the scheduling and rescheduling objective, a discrete harmony search (DHS) algorithm is proposed. To speed up the convergence rate, a local search method is designed. The DHS is applied to two real-life cases for minimizing the maximum completion time and the mean of earliness and tardiness (E/T). These two objectives are also considered together as a bi-objective problem. Computational optimization results and comparisons show that the proposed DHS is able to solve the scheduling and rescheduling problems effectively and productively. Using the proposed approach, satisfactory optimization results can be achieved for scheduling and rescheduling on a real-life shop floor.

The 3D virtual environment online for real shopping

OpenAIRE

Khalil, Nahla

2015-01-01

The development of information technology and Internet has led to rapidly progressed in e-commerce and online shopping, due to the convenience that they provide consumers. E-commerce and online shopping are still not able to fully replace onsite shopping. In contrast, conventional online shopping websites often cannot provide enough information about a product for the customer to make an informed decision before checkout. 3D virtual shopping environment show great potential for enhancing e-co...

RURAL CUSTOMER SATISFACTION TOWARDS ONLINE SHOPPING IN POLLACHI TALUK

OpenAIRE

K. Jayaprakash; A. Pavithra

2017-01-01

Online shopping is a recent phenomenon in electronic commerce and its definitely going to be the future of shopping in the world. It is user friendly compare to in store shopping because consumers can just complete his requirements just with a click of mouse without leaving their home. In the present work, the researcher intended to analyze the most preferred online shopping website, factors influencing the rural customers towards online shopping and to analyze the level satisfaction of the ...

Retention of women accountants: The interaction of job demands and job resources

Directory of Open Access Journals (Sweden)

Stella Ribeiro

2016-05-01

Full Text Available Orientation: Most CEOs in South Africa are chartered accountants (CAs. Retaining women CAs might therefore lead to an increase in women in leadership. The Job Demands-Resources model presents a framework to investigate organisational job-related factors that promote or deter voluntary turnover of women CAs. Research purpose: The primary objective was to investigate which organisational factors promote or reduce the risk of turnover intentions for South African women CAs. The secondary objective was to investigate the moderating potential of job resources on the relationship between job demands and turnover intentions. Motivation for the study: There is a fair amount of research on the problems associated with the retention of women CAs in public practice but very little is known about how those problems interact with each other, and whether there are factors that could buffer them. Research design, approach, and method: The study consisted of a sample (n = 851 of women CAs in public practice firms nationally in South Africa. We used structural equation modelling together with moderated regression analysis. Main findings: Job demands promote turnover intentions, whereas job resources have a negative effect on turnover intentions. Counter-intuitively a negative direct effect was found between job insecurity and turnover intentions. Statistical support was found for the moderating role of all job resources, except financial advancement, on the relationship between work–family conflict and turnover intentions; and growth opportunities, on the relationship between job insecurity and turnover intentions. Practical/managerial implications: No job resource measured could buffer the impact of job overload on turnover intentions. Contribution: This is the first study to investigate factors that may retain women CAs in public practice audit, tax, and advisory firms (Big Four Accountancy Firms using the JD-R model. Few studies have investigated the

48 CFR 252.227-7033 - Rights in shop drawings.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Rights in shop drawings... of Provisions And Clauses 252.227-7033 Rights in shop drawings. As prescribed in 227.7107-(1)(c), use the following clause: Rights in Shop Drawings (APR 1966) (a) Shop drawings for construction means...

48 CFR 1952.227-77 - Rights in shop drawings.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Rights in shop drawings... Rights in shop drawings. As prescribed in 1927.405(h), insert the following clause: Rights in Shop Drawings (FEB 1985) (a) Shop drawings for construction means drawings, submitted to the Government by the...

METODOLOGÍA BASADA EN LOS ALGORITMOS VEGA Y MOGA PARA SOLUCIONAR UN PROBLEMA MULTIOBJETIVO EN UN SISTEMA DE PRODUCCIÓN JOB SHOP

Directory of Open Access Journals (Sweden)

Germán Augusto Coca Ortegón

Full Text Available En este artículo se presenta una metodología que pretende minimizar de forma simultánea, en un ambiente de producción tipo "job shop" correspondiente a una empresa metalmecánica, las siguientes variables: tiempo de proceso, costo de mano de obra directa y, asimismo la fracción defectuosa generada por la fatiga del operario. Con este propósito se fusionan elementos de los algoritmos genéticos Vega y Moga, desarrollando para el efecto las siguientes etapas: generar la población inicial, conformar la nueva población, realizar análisis de varianza y por último, comparar con un método híbrido entre sumas ponderadas y algoritmos genéticos. De acuerdo con lo anterior, al evaluar el individuo de menor tiempo de proceso proveniente de la metodología basada en los algoritmos Vega y Moga, respecto al individuo de menor tiempo de desarrollo proveniente del método híbrido entre sumas ponderadas y algoritmos genéticos, se encuentra que el primero supera en desempeño al segundo así: en cuanto a la variable tiempo de proceso (en horas en 27,86%; en cuanto a la variable tiempo de proceso (en semanas en 1,25%; en cuanto a la variable costo de mano de obra directa (MOD en 6,73% y, en cuanto a la variable fracción defectuosa en 25,85%.

Determinants of Customer Continuance Intention of Online Shopping

Directory of Open Access Journals (Sweden)

Al-maghrabi, T.

2011-01-01

Full Text Available The purpose of this study is to clarify theory and identify factors that could explain the level of continuance intention of e-shopping. A revised technology acceptance model integrates expectation confirmation theory and investigates effects of age differences. An online survey of internet shoppers in Saudi Arabia. Structural equation modelling and invariance analysis confirm model fit. The findings confirm that perceived usefulness, enjoyment and social pressure are determinants of e-shopping continuance. The structural weights are mostly equivalent between young and old but the regression path from perceived usefulness to social pressure is stronger for younger respondents. This research moves beyond e-shopping intentions to factors affecting e-shopping continuance, explaining 55% of intention to continue shopping online. Online strategies cannot ignore direct and indirect effects on continuance intentions. The findings contribute to literature on internet shopping and continuance intentions in the context of Saudi Arabia.

An Exploratory Analysis of Online Shopping Behavior in Turkey

Directory of Open Access Journals (Sweden)

Adnan Veysel Ertemel

2017-06-01

Full Text Available Alongside the technologic developments, transformation in user behavior and business models has been observed. New areas and models are emerged in a lot of grounds like the communication of people or daily activities. So a new face put for shopping behavior by the e-commerce, which is one of the novelties. This study tries to research online shopping behavior in Turkey. With a quantitative research, device usage, the reasons behind to shop or not to shop online, online shopping category and e-commerce site preferences, payment methods, international e-commerce and online marketplace usage is investigated. As implications of the research, “saving time“ is found to be the foremost reason for shopping online in Turkey and “travel and bookings” category is found as the most shopped category among the results of the survey.

Aligning workload control theory and practice : lot splitting and operation overlapping issues

NARCIS (Netherlands)

Fernandes, Nuno O.; Land, Martin J.; Carmo-Silva, S.

2016-01-01

This paper addresses the problem of lot splitting in the context of workload control (WLC). Past studies on WLC assumed that jobs released to the shop floor proceed through the different stages of processing without being split. However, in practice, large jobs are often split into smaller transfer

Job demands and job strain as risk factors for employee wellbeing in elderly care: an instrumental-variables analysis.

Science.gov (United States)

Elovainio, Marko; Heponiemi, Tarja; Kuusio, Hannamaria; Jokela, Markus; Aalto, Anna-Mari; Pekkarinen, Laura; Noro, Anja; Finne-Soveri, Harriet; Kivimäki, Mika; Sinervo, Timo

2015-02-01

The association between psychosocial work environment and employee wellbeing has repeatedly been shown. However, as environmental evaluations have typically been self-reported, the observed associations may be attributable to reporting bias. Applying instrumental-variable regression, we used staffing level (the ratio of staff to residents) as an unconfounded instrument for self-reported job demands and job strain to predict various indicators of wellbeing (perceived stress, psychological distress and sleeping problems) among 1525 registered nurses, practical nurses and nursing assistants working in elderly care wards. In ordinary regression, higher self-reported job demands and job strain were associated with increased risk of perceived stress, psychological distress and sleeping problems. The effect estimates for the associations of these psychosocial factors with perceived stress and psychological distress were greater, but less precisely estimated, in an instrumental-variables analysis which took into account only the variation in self-reported job demands and job strain that was explained by staffing level. No association between psychosocial factors and sleeping problems was observed with the instrumental-variable analysis. These results support a causal interpretation of high self-reported job demands and job strain being risk factors for employee wellbeing. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Specific energy use in Swedish and Norwegian shopping malls

Energy Technology Data Exchange (ETDEWEB)

Stensson, Sofia; Axell, Monica (SP Energy Technology, Boraas (Sweden)); Smaage, Kjell Petter (Evotek AS (Norway)); Fahlen, Per (Chalmers Univ. of Technology, Building Services Engineering, Goeteborg (Sweden))

2009-07-01

The prevalence of shopping malls is growing worldwide. Internationally, there are differences in energy use and system solutions due to local outdoor climate, available energy resources, prices, national building regulations, traditions etc. On the other hand, tenants are usually international chains and they often have the same demands regarding indoor climate, system solutions etc. irrespective of the national differences. Shopping malls overall tends to have large lighting loads, high population density and, hence, a large air conditioning demand. There is also an apparent trend towards increasing glass surfaces and such design feature affects the energy balance of the building. For those interested in the energy efficiency of the building and its installations, it is interesting to know how different system solutions affect the energy use. Benchmarking between buildings gives valuable insight to energy efficient design and operation. However, available information on energy use for such benchmarking in shopping malls is still rather limited. This study investigates shopping malls in Sweden and Norway. Available national statistical data on retail and shopping malls are reviewed. Further building statistical data were collected from building owners and managers, covering energy use in 41 shopping malls. Additional energy use data for 115 shops, within three of these shopping malls were also collected. The building statistical data shows that the average energy use in Norwegian and Swedish shopping malls are approximately 291 and 279 kWh/m2/year respectively. The highest energy use exceeds the lowest figure by approximately 50 percent, indicating a significant potential for improvement. Results also show a wide deviation in energy use of the different shops in a shopping mall. The paper further provides a discussion concerning alternative benchmarking methods and necessary improvements to make valid conclusions regarding energy use in shopping malls.

Turning shopping habits of young consumers into green

NARCIS (Netherlands)

Bialkova, Svetlana; van 't Erve, Sanne; van Hoof, Joris Jasper; Pruyn, Adriaan T.H.; Bigné, Enrique

2014-01-01

Consumers have strong shopping habits, and although being aware of sustainable issues, they hardly do green shopping. Therefore, a challenging question is: how to break the old shopping habits and turn those into green? The current study addresses this question looking at barriers and potential

Typically Female Features in Hungarian Shopping Tourism

Directory of Open Access Journals (Sweden)

Gábor Michalkó

2006-06-01

Full Text Available Although shopping has been long acknowledged as a major tourist activity, the extent and characteristics of shopping tourism have only recently become the subject of academic research and discussion. As a contribution to this field of knowledge, the paper presents the characteristics of shopping tourism in Hungary, and discusses the typically female features of outbound Hungarian shopping tourism. The research is based on a survey of 2473 Hungarian tourists carried out in 2005. As the findings of the study indicate, while female respondents were altogether more likely to be involved in tourist shopping than male travellers, no significant difference was experienced between the genders concerning the share of shopping expenses compared to their total travel budget. In their shopping behaviour, women were typically affected by price levels, and they proved to be both more selfish and more altruistic than men by purchasing more products for themselves and for their family members. The most significant differences between men and women were found in their product preferences as female tourists were more likely to purchase typically feminine goods such as clothes, shoes, bags and accessories, in the timing of shopping activities while abroad, and in the information sources used by tourists, since interpersonal influences such as friends’, guides’ and fellow travellers’ recommendations played a higher role in female travellers’ decisions.

Retailing and Shopping on the Internet.

Science.gov (United States)

Rowley, Jennifer

1996-01-01

Internet advertising and commercial activity are increasing. This article examines challenges facing the retail industry on the Internet: location; comparison shopping; security, especially financial transactions; customer base and profile; nature of the shopping experience; and legal and marketplace controls. (PEN)

Impact of e-shopping on shopping-related travel behaviour: Analyses of the Netherlands Mobility Panel data.

NARCIS (Netherlands)

Hoogendoorn-Lanser, S.; Olde Kalter, Marie-José José Theresia; Schaap, Nina

2015-01-01

From the moment e-shopping emerged, there are speculations about the impact that would have on personal mobility. Questions about the impact of e-shopping on mobility increase due to media coverage on the sharp increase in turnover of Internet purchases and the increasing number of consumers that

Measuring consumer perceptions of online shopping convenience

OpenAIRE

Ferreira, Margarida Bernardo

2016-01-01

The aim of this master thesis is to identify which dimensions of convenience affect consumers’ intention of using online shopping. Also it explores a conceptual model to measuring consumer perceptions of online shopping convenience. This paper contains prospects about online consumer behavior, and the results have important implications for retailers, managers and marketers, related to online shopping strategies. An empirical investigation was carried out to test the hypotheses. In order t...

CERN SHOP CHRISTMAS SALE

CERN Multimedia

Visits & Exhibition Service

2000-01-01

Looking for Christmas present ideas? Come to the Reception Shop Special Stand in Meyrin, Main Building, ground floor, from Tuesday 12 to Thursday 14 December from 10.00 to 16.00.   Sweat-shirt col zippé, grey, blue, black (M, L, XL) 30.- Sweat-shirt col polo, grey, collar blue (M, L, XL) 30.- T-shirt, black, (M, L, XL) 15.- WWW T-shirt, white, bordeau (M, L, XL) 15.- CERN silk tie (3 colours) 33.- Fancy silk tie (blue, bordeau 25.- Silk scarf (blue, red, yellow) 35.- Swiss army knife with CERN logo 25.- New model of CERN watch 25.- New CERN baseball cap 10.- Antimatter (English/anglais) 30.- The Search for Infinity (French, Italian, English,) 35.- Auf der Suche nach dem Unendlichen 45.- If you miss this special occasion, the articles are also available at the Reception Shop in Building 33 from Monday to Saturday between 08.30 and 17.30 hrs (Shop will be closed at 12.00 on 22.12.).

An architecture for agile shop floor control systems

DEFF Research Database (Denmark)

Langer, Gilad; Alting, Leo

2000-01-01

as shop floor control. This paper presents the Holonic Multi-cell Control System (HoMuCS) architecture that allows for design and development of holonic shop floor control systems. The HoMuCS is a shop floor control system which is sometimes referred to as a manufacturing execution system...

Tourist shopping behavior in a historic downtown area

NARCIS (Netherlands)

Kemperman, A.D.A.M.; Borgers, A.W.J.; Timmermans, H.J.P.

2009-01-01

Shopping is one of the most important activities for tourists. The purpose of this study is to describe and predict tourist shopping route choice behavior in a downtown historic center. Reported routes of tourists in the downtown shopping area of Maastricht, located in the Southern part of the

The impact of science shops on university research and education

DEFF Research Database (Denmark)

Hende, Merete; Jørgensen, Michael Søgaard

This report discusses the impact from university-based science shops on curricula and research. Experience from science shops show that besides assisting citizen groups, science shops can also contribute to the development of university curricula and research. This impact has been investigated...... through the SCIPAS questionnaire sent out to science shops and through follow-up interviews with employees from nine different university-based science shops and one university researcher. Not all the cases call themselves science shops, but in the report the term 'science shop' will be used most...... way or the other has had impact on university curricula and/or research. The analysis and the case studies have theoretically been based on literature on universities and education and research as institutions and a few articles about the impact of science shops on education and research. The analysis...

Supporting workers with mental health problems to retain employment: users' experiences of a UK job retention project.

Science.gov (United States)

Cameron, Josh; Walker, Carl; Hart, Angie; Sadlo, Gaynor; Haslam, Imogen; Retain Support Group

2012-01-01

To understand experiences and perspectives of job retention project users in relation to challenges faced and support received; to develop explanatory insight into effective interventions. 14 employed users of a United Kingdom job retention project, with a range of mental health problems. Semi-structured individual interviews which were collaboratively designed with service users. Data analysis involved deductive & inductive thematic analysis, constant comparative analysis, and service user collaboration. Participants' feelings of guilt and self blame were a major obstacle to job retention. The project helped them address these by supporting a reappraisal of their situation. This assisted identification of job accommodations and adjustments and confidence in self advocacy. Thus an important basis for improved dialogue with their employer was established. A peer support group provided an important adjunct to individual project worker interventions. 10 participants retained employment; three of those who did not were helped to retain work aspirations. The project effectively used a multi-faceted approach involving a person - environment-occupation focus on the worker, their work, and workplace. Such complex interventions may offer more promise than those interventions (such as cognitive behavioural therapy) which have a primary focus on the individual worker.

E-COMMERCE FACTORS INFLUENCING CONSUMERS‘ ONLINE SHOPPING DECISION

Directory of Open Access Journals (Sweden)

Živilė Baubonienė

2015-12-01

Full Text Available Purpose – The purpose of this paper is to look at the factors driving online shopping and to develop an understanding of the factors influencing the online shopping by the consumers. This is done by exploring the factors that encourage consumers to shop online through analysis of such advantages as security, fast delivery, comparable price, convenience, cheaper prices and a wider choice. At the same time, the research project reveals the factors that are discouraging for consumers and the benefits received by buyers making purchases online. Specifically, the research explores how online shopping can be affected by such factors as age, gender or occupation. Design/methodology/approach – The factors that affect the consumer online shopping have been disclosed through quantitative research by analysing data collected via a web‐based questionnaire survey. The sample consisted of 183 Lithuanian consumers who were purchasing online. Findings –The empirical findings of this study indicate that the main factors influencing consumers to shop online are convenience, simplicity and better price. Analysis of socio-demographical characteristics such as gender has shown that men shop more often online because of the lower price. Respondents of the 25–35 year age group more often choose shopping online for such reasons as lack of time and a wide range of products. The most beneficial factor of shopping online was identified as a possibility to compare prices and buy at a lower price. Research limitations/implications – This study was done regarding only general conditions and the findings may not necessarily be applicable to a particular e-business. Therefore, in the future it would be highly encouraged to examine consumers’ attitudes towards specialized online shopping websites to look for differences by kind of products or services.Practical implications – Attributes identified by this study could help e-business developers to forme their

Product Characteristics and Internet Shopping Intentions.

Science.gov (United States)

Vijayasarathy, Leo R.

2002-01-01

Discussion of electronic commerce and online marketing focuses on an empirical study that investigated differences between Internet shopping intentions for products categorized by cost and tangibility. Highlights include hypotheses; respondent characteristics; results that showed that intentions to shop using the Internet differ by tangibility of…

Rental Values in UK Shopping Malls

NARCIS (Netherlands)

Yuo, Tony Shun-Te; Lizieri, Colin; McCann, Phillip; Crosby, Neil

This paper employs a unique dataset to analyse the retail rental levels of 1108 retail tenants in 148 UK regional shopping malls. The dataset integrates information regarding the characteristics of the shopping centre, the individual retailer, the brand, the individual unit occupied, the tenancy

Single-machine scheduling of proportionally deteriorating jobs by two agents

OpenAIRE

S Gawiejnowicz; W-C Lee; C-L Lin; C-C Wu

2011-01-01

We consider a problem of scheduling a set of independent jobs by two agents on a single machine. Every agent has its own subset of jobs to be scheduled and uses its own optimality criterion. The processing time of each job proportionally deteriorates with respect to the starting time of the job. The problem is to find a schedule that minimizes the total tardiness of the first agent, provided that no tardy job is allowed for the second agent. We prove basic properties of the problem and give a...

Cellular Phone Users- Willingness to Shop Online

OpenAIRE

Norazah Mohd Suki; Norbayah Mohd Suki

2009-01-01

This study aims to identify cellular phone users- shopping motivating factors towards online shopping. 100 university students located in Klang Valley, Malaysia were involved as the respondents. They were required to complete a set of questionnaire and had to own a cellular phone in order to be selected as sample in this study. Three from five proposed hypotheses were supported: purchasing information, shopping utilities and service quality. As a result, marketers and retailers should concent...

CONSUMER BEHAVIOUR AND ATTITUDE TOWARDS ONLINE SHOPPING

OpenAIRE

S. Nethra; Dr. V. T. Dhanaraj

2016-01-01

The popularity of online shopping has caught the attention of many peoples. Many studies have been done in developed nations to know about the attitude and behaviour of consumers towards online shopping. The research is focused on consumer behaviour and attitude towards online shopping in Coimbatore district. The study is based on primary data which has been collected by issuing questionnaire to 200 respondents residing in Coimbatore district by adopting convenient sampling method. The stat...

Passion and dependency in online shopping activities.

Science.gov (United States)

Wang, Chih-Chien; Yang, Hui-Wen

2007-04-01

This study examines the influence of harmonious passion (HP) and obsessive passion (OP) to online shopping dependency. The results show that both HP and OP might lead to online shopping dependency and online shoppers with OP are more dependent on online shopping activities. In addition, this study also found out that HP and OP could be denoted as a sequence of different intensities of passion, where HP might be a necessity of OP.

Breaking Out of the Local: International dimensions of science shops

Directory of Open Access Journals (Sweden)

Caspar DeBok

2008-09-01

Full Text Available In this article we want to give an overview of the international dimension and the interest of the European Union (EU in the concept of Science Shops. The European Commission (EC manages the day-to-day business by initiating and implementing EU policies and spending EU funds. The EC support for Science Shops has been an important factor for the international interest and progress of the Science Shop movement. This article will not give detailed information about daily routines of a Science Shop. Detailed information about the Science Shop concept can be found at the Living Knowledge website (www.livingknowledge.org. Living Knowledge represents the international Science Shop Network. In this article international developments of the Science Shop Network, like the project TRAMS, and Science Shop backgrounds will be linked with past and new EU policies like the EU 7th Framework Programme for Research. It shows how community-based research does not only have a local dimension. The international Science Shop activities show the strengths of international cooperation to break out of the local and to bring local issues on the international agenda. Detailed information about the Science Shop concept and daily routines of a Science Shop can be found at the Living Knowledge website (www.livingknowledge.org, e.g. at the FAQ section and in the toolbox.

Power Service Shops

Data.gov (United States)

Federal Laboratory Consortium — TVA's Power Service Shops provides expert repair and maintenance of power system components and large industrial equipment. With world-class maintenance facilities...

What do we know about consumer m-shopping behaviour?

OpenAIRE

Marriott, Hannah; Williams, Michael; Dwivedi, Yogesh

2017-01-01

Purpose – This paper provides a review of mobile shopping (m-shopping) acceptance literature to bring international marketing and consumer research attention to m-shopping acceptance factors and limitations in current understandings to propose recommendations for further academic and retailing attention.\\ud Design/methodology – Keyword searches identified consumer-focused literature across mobile commerce, mobile shopping, mobile browsing, and mobile purchasing, published in English language ...

Job-Sharing: An Answer to Productivity Problems?

Science.gov (United States)

Frease, Michael; Zawacki, Robert A.

1979-01-01

Proponents stress the increased productivity that results for job sharers' ability to work harder for shorter periods of time. Opponents stress the increased expenses, such as fringe benefits, that result. The issue, then, is whether increased productivity outweighs increased expenses. (Author/IRT)

Hedonic Motivations for Online Shopping

OpenAIRE

Pui-Lai To; E-Ping Sung

2014-01-01

The purpose of this study is to investigate hedonic online shopping motivations. A qualitative analysis was conducted to explore the factors influencing online hedonic shopping motivations. The results of the study indicate that traditional hedonic values, consisting of social, role, self-gratification, learning trends, pleasure of bargaining, stimulation, diversion, status, and adventure, and dimensions of flow theory, consisting of control, curiosity, enjoyment, and telepresence, exist in t...

Food Shopping and Acquisition Behaviors in Relation to BMI among Residents of Low-Income Communities in South Carolina