• Journal of applied mathematics & informatics
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• 제18권1_2호
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• pp.383-391
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• 2005

The paper is devoted to some flow shop scheduling problems, where job processing times are defined by functions dependent on their positions in the schedule. An example is constructed to show that the classical Johnson's rule is not the optimal solution for two different models of the two-machine flow shop scheduling to minimize makespan. In order to solve the makespan minimization problem in the two-machine flow shop scheduling, we suggest Johnson's rule as a heuristic algorithm, for which the worst-case bound is calculated. We find polynomial time solutions to some special cases of the considered problems for the following optimization criteria: the weighted sum of completion times and maximum lateness. Some furthermore extensions of the problems are also shown.

• 한국조경학회지
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• 제25권4호
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• pp.51-60
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• 1998

The purpose of this study was investigating the managers' consciousness on the interior landscape in coffee shop, the actual measurement of the space size and greenary spaces of coffee shop for grasping the actual condition of interior landscape. The coffee shop was made and object of this research was 100 cases in the center of Taegu city. The major results of actual measurement of the ratio greenary and spaces are as follows; 1. The ratio greenary spaces in the indoor plants was account for 2.06% of the coffee shop area. 2. The managers recognized that the spaces area of the interior plantscape were narrow comparison with whole spaces area about the interior landscape. 3. A major arrangement type of the interior landscape was the dispersion type. 4. A major plants used for the interior landscape were foliage plants and also most of managers prefered foliage plant. 5.Generally, managers were high interested in the interior landscape but the experience knowledge and investment in the interior landscape were not sufficient.

• 음성과학
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• 제15권4호
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• pp.121-130
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• 2008

This paper proposes the way of improvement and system build-up for shop music broadcasting services provided by the Internet. Comparing the shop music broadcasting services and personal music broadcasting services, we propose the way of shop music broadcasting services customers prefer to. That is, such a function is provided that a user can control the broadcasting music lists a specialist provides according to the current circumstance of shop. This paper proposes the whole system such a service is possible and verifies the efficiency by experiments.

• 패션비즈니스
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• 제19권4호
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• pp.75-91
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• 2015

There is an increased interest in having beauty regardless of ages and sex with improvement of the national income level and increase in social activities. Competition within the beauty service industry is increasing rapidly because of global impact within Korea wave. Thus, active public relations and offering distinguished service in the beauty service industry are important. Also, uniforms play an important role in providing an image differentiated from other brands and presents professionalism to the customer. Therefore, we determined function and design of uniforms required in beauty service industry by researching wearing realities, satisfaction, preferred designs and functions of uniforms from hair shop staff. Functional and aesthetic uniforms play an important role to enhance the staffs' sense of belonging. In addition, it is good for the image of hair shop. Special design mirroring job characteristics with expression of differentiated personalities is needed. However, the research was conducted only in the hair shop in Seoul, Daejeon, and Gyeonggi-do. Further studies on much wider areas will be needed.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1996년도 춘계학술대회
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• pp.15-15
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• 1996

A shop floor control system (SFCS) is the central part of a CIM system used to control the activities of several pieces of manufacturing equipment (e.g., NC machines, robots, conveyors, AGVs, AS/RS). The SFCS receives orders and related process plans, and then performs selecting a specific process routing, allocating resources, scheduling the workpieces, downloading the processing instructions (e.g., RS-274 instructions for NC machines, VAL II programs for robot), monitoring the progress of activities, detecting and recovering from errors, and preparing reports on the status of the manufacturing system. Simulation has been utilized in discovering control policies used for resolving shop floor be control problems such as resource contentions, part dispatching, deadlock. The simulation model must be designed to respond to real-time data coming from a shop floor. However, to rapidly build a realtime simulation model of SFCS cannot be easily accomplished. This talk is to address an automatic program generator of discrete event simulation model for shop floor control from process plans and resource models. The program generator is capable of constructing complete discrete simulation models for multi-product and multi-stage flexible manufacturing systems.

• 산업경영시스템학회지
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• 제20권43호
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• pp.127-137
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• 1997

This paper proposes a heuristic method for job shop scheduling with alternative machines. Our heuristic suggests two machine-selecting rules and two priority dispatching rules for modifying existent ones considering alternative machines, and then it extends existing nondelay/active job shop schedule generation. This heuristic provides good criteria(rules) in the selection of a proper machine among those performing a specific operation and for the dispatch of an operation to a selected machine and thus these rules permit the efficient job shop scheduling with alternative machines. The performances of our two machine-selecting rules in addition to the two priority dispatching rules, applied together with the existing 17 rules, are experimented and evaluated, respectively.

• Ocean Systems Engineering
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• 제2권4호
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• pp.271-287
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• 2012

Due to its large size, a ship is first divided into scores of blocks and then each block is constructed through various shops, such as the assembly shop, the painting shop, and the outfitting shop. However, each block may not be directly moved to the next shop and may be temporarily laid at a block stockyard because the working time in each shop is different from each other. If blocks are laid at the block stockyard without any planning, the rearrangement of the blocks by a transporter is required because the blocks have the different in and out time. In this study, a block layout method based on the genetic algorithm was proposed in order to minimize the rearrangement of the blocks in the block stockyard. To evaluate the applicability of the proposed method, it was applied to simple layout problems of the block stockyard. The result shows that the proposed method can yield a block layout that minimizes the total relocation cost of moving obstacle blocks in the block stockyard.

• 산업경영시스템학회지
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• 제23권56호
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• pp.9-18
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• 2000

This paper considers the problem of two-machine, M-parallel flow shop scheduling to minimize makespan, and proposes a series of heuristic algorithms and a branch and bound algorithm. Two processing times of each job at two machines on each line are identical on any line. Since each flow-shop line consists of two machines, Johnson's sequence is optimal for each flow-shop line. Heuristic algorithms are developed in this paper by combining a "list scheduling" method and a "local search with global evaluation" method. Numerical experiments show that the proposed heuristics can efficiently give optimal or near-optimal schedules with high accuracy. with high accuracy.

• 산업경영시스템학회지
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• 제29권4호
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• pp.107-112
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• 2006

This study presents the new dispatching rules for improving performance measures of job shop scheduling related to completion time and due dates. The proposed dispatching rule considers information, which includes the comparison value of job workload, work remaining, operation time, and operation due dates. Through computer experiments, the performance of the new dispatching rules is compared and analyzed with the existing rules. The results provide a guidance for the researchers to develop new dispatching rules and for practitioners to choose rules of job shop scheduling.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.707-717
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• 2021

To the date, shipbuilding companies have applied shop primer coating which protects the steel surface from global oxidization in environment. Proper shop primer requires either anti-corrosion ability during construction or anti-porosity ability during welding, and those properties contradict to each other. This report tried to derive an optimizing parameter on these conflicting properties to select a proper shop primer. First, sufficient amounts of the natural salt spray tests were carried out to achieve a series of data for the anti-corrosion ability. Second, lots of T-joint fillet welding test were performed to evaluate the trapped porosity formed in the weld pool. According to the experimental data, we could achieve either the rust-formation rate or the porosity-formation rate, then, each rate was generalized as formulae. Then, we tried to combine these conflicting properties to decide an optimum shop primer.