Research on Cell Manufacturing Facility Layout Problem Based on Improved NSGA-II

With the rapid development of the individualized demand market,the demand for manufacturing flexibility has increased over time.As a result,a cell manufacturing system suitable for many varieties and small batches has been produced.With the goal of minimizing the area and logistics handling volume,and considering the arrangement order of facilities and channel constraints,a mathematical model was established,and the problem was solved by improved NSGA-II.After non-dominated sorting,traditional NSGA-II will cross-operate the individuals with the best sorting to generate new individuals.Such a selection strategy is extremely easy to fall into the local optimal solution.The improved NSGA-II is to improve the original selection operation,which is to select the first half of the excellent individuals in the non-dominated sorting into the cross operation,and then select the last sorted ones of the remaining individuals into the cross operation,and combine the best and the worst ones into the cross operation.Finally,an example is given to simulate and improve the solution of NSGA-II and NSGA-II.The simulation results indicate that the improved NSGA-II population shows more obvious diversity,it is easier to jump out of the local optimal solution than NSGA-II,and the satisfactory layout scheme of manufacturing cells is obtained.Therefore,it is more effective to use improved NSGA-II to solve the problem of manufacturing cell layout.

An Algorithm for Solving Generalized Single Row Facility Layout Problem

Layout design problem is to determine a suitable arrangement for the departments so that the total costs associated with the flow among departments become least. Single Row Facility Layout Problem, SRFLP, is one of the layout problems that have many practical applications. This problem and its specific scenarios are often used to model many of the raised issues in the field of facility location. SRFLP is an arrangement of n departments with a specified length in a straight line so that the sum of the weighted distances between the pairs of departments is minimized. This problem is NP-hard. In this paper, first, a lower bound for a special case of SRFLP is presented. Then, a general case of SRFLP is presented in which some new and real assumptions are added to generate more practical model. Then a lower bound, as well as an algorithm, is proposed for solving the model. Experimental results on some instances in literature show the efficiency of our algorithm.

Redesign Facility Layout with a Kaizen Approach in Testing Laboratory at Balai Pengujian&Sertifikat Mutu Barang Makassar

In trading activities,especially exports in the food commodities sector,several documents must be made and completed by exporters,such as Certificate of Quality,Test-Certificate,and Chemical Analysis.Balai Pengujian&Sertifikasi Mutu Barang Makassar is a government agency operating in South Celebes that tests the quality of various agricultural and plantation commodities.From year to year,demand for testing services has increased along with the number of exports.So,testing activities have changed in terms of facility layout requirements resulting in overwhelmed in carrying out the testing process.Test rooms are not connected based on the current testing flow causing the tester’s ineffective work patterns.This study aims to redesign the layout of the facilities in the testing laboratory with the Kaizen approach to support the smooth testing process.The results of this study indicate that the proposed floor area uses a 150% allowance so the calculation requires a floor area of 42.52 m^(2).After that,an analysis of the proximity of the facilities is carried out by making ARC(Activity Relationship Chart)and ARD(Activity Relationship Diagram).Based on ARD,a template is made for the layout of testing laboratory facilities.This study applies Kaizen theory with the 5S concept to obtain a neater design,namely Seiri and Seiton in the refreshment laboratory and weighing room,Seiso on testing equipment in all testing laboratory rooms,Seiketsu and Shitsuke applied to all rooms in the testing laboratory.

Competitive location problem of multi-level pickup point considering cooperative coverage

To occupy a greater market share in terminal distribution, companies are urged to make full use of cooperative coverage formed with brand effect and information sharing in the layout of pickup points. Based on the diversity of pickup points, the piecewise function, signal intensity function and probability function are introduced. Meanwhile, considering the effect of distance satisfaction and cooperation coverage on customer behavior, the location model of the pickup point under competitive environments is established. The genetic algorithm is used to solve the problem, and the effectiveness of the model and algorithm is verified by a case. The results show that the sensitivity of weighted demand coverages to budget decreases gradually. The maximum weighted demand coverage increases at first and then decreases with the increase of the signal threshold, and there is a positive correlation with the change of the actual demand coverage to the senior customers, but it is negatively related to the intermediate and primary customers. When the number of high-level pickup points in a competitive enterprise is small, the advantage of the target enterprise is more significant. Through comparison, the cooperative coverage model is better than the non-cooperative coverage model, in terms of the weighted demand coverage, the construction cost and the attention paid to the important customers.

INTEGRATED LAYOUT DESIGN OF CELLS AND FLOW PATHS

The integrated layout problem in manufacturing Systems is investigated. Anintegrated model for Concurrent layout design of cells and flow paths is formulated. A hybridapproach combined an enhanced branch-and-bound algorithm with a simulated annealing scheme isproposed to solve this problem. The integrated layout method is applied to re-layout the gear pumpshop of a medium-size manufacturer of hydraulic pieces. Results show that the proposed layout methodcan concurrently provide good solutions of the cell layouts and the flow path layouts.

Virtual Facilit Layout Design Using Virtual Reality Techniques

Manufacturing facility layout design has long been recognized as one of the most critical and difficult design tasks in manufacturing industries. Traditional layout methods can not fully solve this complex spatial layout problem. Virtual reality (VR) is a new form of human\|computer interaction, which has the potential to support a range of engineering applications. This paper discusses the reasons why manufacturing facility layout design is considered to be an appropriate new area of VR utilization. A VR\|based layout design framework is proposed. The virtual environment construction issues are discussed. An example of the immersive VR application of facility layout is examined.

An extended discrete particle swarm optimization algorithm for the dynamic facility layout problem

We extended an improved version of the discrete particle swarm optimization (DPSO) algorithm proposed by Liao et al.(2007) to solve the dynamic facility layout problem (DFLP). A computational study was performed with the existing heuristic algorithms, including the dynamic programming (DP), genetic algorithm (GA), simulated annealing (SA), hybrid ant system (HAS), hybrid simulated annealing (SA-EG), hybrid genetic algorithms (NLGA and CONGA). The proposed DPSO algorithm, SA, HAS, GA, DP, SA-EG, NLGA, and CONGA obtained the best solutions for 33, 24, 20, 10, 12, 20, 5, and 2 of the 48 problems from (Balakrishnan and Cheng, 2000), respectively. These results show that the DPSO is very effective in dealing with the DFLP. The extended DPSO also has very good computational efficiency when the problem size increases.

A Mixed-Integer Programming Formulation for a Simplified Model of the Double Row Layout Problem

The double row layout problem(DRLP)is to assign facilities on two rows in parallel so that the total cost of material handling among facilities is minimized.Since it is vital to save cost and enhance productivity,the DRLP plays an important role in many application fields.Nevertheless,it is very hard to handle the DRLP because of its complex model.In this paper,we consider a new simplified model for the DRLP(SM-DRLP)and provide a mixed integer programming(MIP)formulation for it.The continuous decision variables of the DRLP are divided into two parts:start points of double rows and adjustable clearances between adjacent facilities.The former one is considered in the new simplified model for the DRLP with the purpose of maintaining solution quality,while the latter one is not taken into account with the purpose of reducing computational time.To evaluate its performance,our SM-DRLP is compared with the model of a general DRLP and the model of another simplified DRLP.The experimental results show the efficiency of our proposed model.

Towards modeling pedestrian’s invisible trail for simulating crowd movement

Facility layout problem(FLP)contemplates the optimization of space utilization,costs,and material flow.Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow and production process.To validate a layout scenario of a solar module assembly workshop,a 3D simulation model is presented which was designed on VisualComponents software.To begin with,we introduce the layout characteristics and use the systematic layout planning(SLP)method to design the block layout of workshop.Then,we built components library which contains all the facilities needed in the production line,specifically conveyors,processing equipments,robots,buffers.Finally,we have established a simulation layout model using the components in the customized library according to the block layout,and configured the components which were allocated in the layout by setting the parameters and building the connection between components via signal.To improve the performance of the workshop,we have found the best work-in-process(WIP)value for the workshop and the optimal number of workers.Additionally,the layout model was used to test collision and reachability.It demonstrated the production process in a realistic simulation environment which helped in the sales process as well.The reusable component models we have built make it easy to build a layout within a short time and validate the effectiveness of the layout scenarios for any other projects.

Using simulation in layout verification of solar module assembly workshop

Facility layout problem(FLP)contemplates the optimization of space utilization,costs,and material flow.Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow and production process.To validate a layout scenario of a solar module assembly workshop,a 3D simulation model is presented which was designed on VisualComponents software.To begin with,we introduce the layout characteristics and use the systematic layout planning(SLP)method to design the block layout of workshop.Then,we built components library which contains all the facilities needed in the production line,specifically conveyors,processing equipments,robots,buffers.Finally,we have established a simulation layout model using the components in the customized library according to the block layout,and configured the components which were allocated in the layout by setting the parameters and building the connection between components via signal.To improve the performance of the workshop,we have found the best work-in-process(WIP)value for the workshop and the optimal number of workers.Additionally,the layout model was used to test collision and reachability.It demonstrated the production process in a realistic simulation environment which helped in the sales process as well.The reusable component models we have built make it easy to build a layout within a short time and validate the effectiveness of the layout scenarios for any other projects.