• IE interfaces
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• v.5 no.2
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• pp.75-85
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• 1992

A common problem for manufacturing industries, especially consumer goods industries, is how to establish standardized procedures for loading finished goods onto pallets or containers for subsequent storage and distribution. Utilizing previous research results on the palletizing problem, this paper develops micro-computer based programs which generate an optimum loading pattern leading to the minimum amount of unused pallet or container space. Development of pallet layout chart is also included in the computer programs. The results are displayed by computer-graphic. For the users who are unfamiliar with pallet loading problem and computer system, pull-down menu and user-computer interactive data input procedures are adopted.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.3
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• pp.43-53
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• 2009

The pallet loading problem(PLP) requires the best orthogonal layout that loads the maximum number of identical boxes(small rectangle) onto a pallet(large rectangle). Since the high pallet utilization saves the distribution and storage costs, many heuristic and exact algorithms have been developed so far. Martins and Dell have found the optimal layouts for the all PLPs less than or equal to 100 boxes except for only 5 problems in their recent research. This paper defines the 'stair structure' and proposes a new exact algorithm applying it. In order to show the priority of the proposed algorithm, computational results are compared to previous algorithms and the optimal layouts for the S unsolved problems are given.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.4
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• pp.470-480
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• 2008

Loading steel coil products on a specialized packing case called pallet can be represented as a bin-packing problem with the special constraint where objects should be loaded on designated positions of bins. In this paper, under assuming that there exist only two types of objects, we focus on finding the optimum number of positions in a bin which minimizes the number of bins needed for packing a collection of objects. Firstly, we propose a method to decide the number of positions and prove that the method is optimum. Finally, for the packing problem using bins designed by the method, we show that the well-known algorithm, First-Fit Decreasing(FFD), is the optimum algorithm.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.5
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• pp.609-616
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• 2007

Palletizing is necessary to promote the efficiency of storage and shipping tasks. These are, however some of the most monotonous, heavy and laborious tasks in the factory. Therefore many types of robot palletizing systems have been developed, but many robot motion commands still depend on the teaching pendent. That is, an operator inputs the motion command lines one by one. It is very troublesome, and most of all, the user must know how to type the code. That is why we propose a new GUI (Graphic User Interface) Palletizing System. To cope with this issue, we proposed a 'PLP' (Pallet Loading Problem) algorithm, Fast Algorithm and realize 3D auto-patterning visualization interface. Finally, we propose the robot palletizing simulator. Internally, the schematic of this simulator is as follows. First, an user inputs the physical information of object. Second, simulator calculates the optimal pattern for the object and visualizes the result. Finally, the calculated position data of object is passed to the robot simulator. To develop the robot simulator, we use an articulated robot, and analyze the kinematics and dynamics. Especially, All problem including thousands of boxes were completely calculated in less than 1 second and resulted in optimal solutions by the Fast Algorithm.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.4
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• pp.59-69
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• 2018

This study deals with the case study on the pallet quantity determination problem for the flexible manufacturing system producing 32 different types of aircraft wing ribs which are major structures of an aircraft wings. A Korean company has constructed the WFMS (wing rib flexible manufacturing system) that is composed of several automated equipments such as the 5-axis machining centers, the RGV (rail guided vehicles)s, the AS/RS (automated storage and retrieval system), the loading/unloading stations, and so on. Pallets play a critical role in the WFMS to maintain high system utilization and continuous work flow between 5-axis machining machines and automated material handling devices. The discrete event simulation method is used to evaluate the performance of the WFMS under various pallet mix alternatives for wing rib manufacturing processes. Four performance measures including system utilization, throughput, lead-time and work in process inventory level are investigated to determine the best pallet mix alternative. The best pallet mix identified by the simulation study is adopted in setting up and operating a real Korean aircraft parts manufacturing shop. By comparing the real WFMS's performances with those of the simulation study, we discussed the cause of performance difference observed and the necessity of developing the CPS (cyber physical system).

• Journal of the Semiconductor & Display Technology
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• v.22 no.3
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• pp.36-40
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• 2023

Recently, in the problem of multi-order processing in logistics warehouses, multi-pickup systems are changing from the form in which workers walk around the warehouse to the form in which goods come to workers. These changes are shortening the time to process multiple orders and increasing production. This study considered the sequence problem of which warehouse the items to be loaded on each truck come first and which items to be loaded first when loading multiple pallet-unit goods on multiple trucks in an industrial smart logistics automation warehouse. To solve this problem efficiently, we use the mutant algorithm, which combines the GA algorithm and ACO algorithm, and compare with original system.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1250-1255
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• 1990

This paper discusses an optimal cyclic scheduling problem for a FMC (Flexible Manufacturing Cell) modeled by a two-machine flowshop with two machining centers with APC's (Automated Pallet Changers), an AGV (Automated Guided Vehicle) and loading and unloading stations. Cyclic production in which similar patterns of production is repeated can significantly reduce the production lead-time and WIP (Work-In-Process) in such flexible, automated system. Thus we want to find an optimal cyclic schedule that minimizes the cycle time in each cycle. However, the existence of APC's as buffer storage for WIP makes the problem intractable (i.e., NP-complete). We propose an practical approximation algorithm that minimizes, instead of each cycle time, its upper bound. Performances of this algorithm are validated by the way of computer simulations.

• Journal of the Korea Safety Management & Science
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• v.13 no.4
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• pp.25-33
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• 2011

Workers in logistics centers also are exposed to serious musculoskeletal disorders the same as workers in general manufacturing due to operating forklifts and other labor duties. The frequency of these work related injuries decreases, workers' job satisfaction In addition, it causes many employees questioning a job change, which is regarded as the primary factor which drops the productivity. In this paper, we conducted a survey ti perceive the correlation between work related injuries in the fields of distribution centers and job satisfaction. Furthermore we made statistical analysis with our findings. The results of our analysis showed that the frequency of work related injuries due to workers' repetitive loading and unloading work is the primary factor which lowers job satisfaction. In order to improve aforementioned problem we propose first of all loading and unloading on pallet basis, second of all automation and computerization of logistics systems, and third of all ensurinf sufficient break time.

• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.4
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• pp.31-37
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• 2003

This paper deals with a stowage plan for plates in a warehouse. This plan includes how to place each plate and how to sequence outgoing lots for picking. A group of plates in an outgoing lot should be loaded in the same outgoing pallet and between two elates in the same lot, no plate from other than the lot should be placed. Since the approach to the plates is only from above, when the plates in the different lots are placed mixed in a warehouse, we have to temporarily move many of plates in some other place to let a plate in the lot for which loading is under way go out. Our purpose is to minimize those temporary moves. We analyze the computational complexity of several problems arising in the stowage plan of a plate warehouse.