• Journal of Power Electronics
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• 제15권3호
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• pp.849-859
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• 2015

This paper proposes a novel compound-type hybrid energy storage system (HESS) that inherits the unique advantages of both battery/supercapacitor (SC) and the SC/battery HESSs for electric vehicles (EVs). Eight operation modes are designed to match this system. A mode control strategy is developed for this HESS on the basis of these modes, and five classes of operation modes are established to simplify this strategy. The mode control strategy focuses on high operating efficiency and high power output. Furthermore, the compound-type HESS is designed such that the SC is the main priority in braking energy absorption. Thus, this HESS can operate efficiently and extend battery life. Simulation results also show that the compound-type HESS can not only supply adequate power to the motor inverter but can also determine suitable operation modes in corresponding conditions. Experimental results demonstrate that this HESS can extend battery life as well. The overall efficiency of the compound-type HESS is higher than those of the battery/SC and the SC/battery HESSs.

• 산업공학
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• 제14권2호
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• pp.127-133
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• 2001

Virtual Manufacturing is a technology facilitating effective development and agile production of products via computer models representing physical and logical schema and the behavior of the real manufacturing systems. For the successful application of this technology, a virtual plant as a well-designed and integrated environment is essential. We propose a series of systematic approaches and effective methods for construction and operation of a virtual plant in this paper, such as a 3-D CAD modeling, cell and line simulations and databases. We developed key technologies for measuring and 3-D CAD modeling of many equipments, facilities and structures of the buildings. In order to study the benefit of virtual manufacturing, we constructed a sophisticated virtual plant model of a Korean automotive company's body shop, and conducted precise simulations of unit cell, lines and the whole plant. We could obtain the benefit of savings in time and cost in many manufacturing preparation activities in the new car development processes.

• 산업공학
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• 제13권4호
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• pp.639-645
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• 2000

Virtual manufacturing systems that perform production activities ahead of real production in virtual world can reduce time and cost to develop, design, plan, and manage new products. In this paper, a virtual manufacturing system is constructed as a tool to support decision making by using VRML and Java. The basic structure of the virtual manufacturing system and the operation models are also presented. The developed system helps any related persons to share design and manufacturing information, and to perform their tasks collaboratively through Internet. The other function of the system is to monitor operation status in real time.

• 한국생산제조학회지
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• 제8권1호
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• pp.15-20
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• 1999

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.2.1-2.7
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• 2018

With the development of computer-aided design/computer-aided manufacturing (CAD/CAM) technology, it has been possible to reconstruct the cranio-maxillofacial defect with more accurate preoperative planning, precise patient-specific implants (PSIs), and shorter operation times. The manufacturing processes include subtractive manufacturing and additive manufacturing and should be selected in consideration of the material type, available technology, post-processing, accuracy, lead time, properties, and surface quality. Materials such as titanium, polyethylene, polyetheretherketone (PEEK), hydroxyapatite (HA), poly-DL-lactic acid (PDLLA), polylactide-co-glycolide acid (PLGA), and calcium phosphate are used. Design methods for the reconstruction of cranio-maxillofacial defects include the use of a pre-operative model printed with pre-operative data, printing a cutting guide or template after virtual surgery, a model after virtual surgery printed with reconstructed data using a mirror image, and manufacturing PSIs by directly obtaining PSI data after reconstruction using a mirror image. By selecting the appropriate design method, manufacturing process, and implant material according to the case, it is possible to obtain a more accurate surgical procedure, reduced operation time, the prevention of various complications that can occur using the traditional method, and predictive results compared to the traditional method.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.181-188
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• 2019

A production system is a management system that supports all activities to perform production operations at the manufacturing site. From the point-of-view of a smart factory, smart manufacturing systems redesigned the concept of onsite production systems to fit the entire system and its necessary functional composition. In this study, we select the key functions needed to build a smart factory for a PCB line and propose a new six-step model for the deployment of a smart manufacturing system by integrating essential functions. The smart manufacturing system newly classified the production and operation tasks of PCB manufacturing and selected necessary functions through requirement analysis and benchmarking of advanced companies. The selected production operation tasks are mapped to the functions of the system and configured into seven modules, and the optimal deployment model is presented to allow flexible responses to the characteristics of the tasks. These methodologies are first presented in this study, and the proposed model was applied to the PCB line to confirm that they had significant changes in the work method, qualitative effects, and quantitative effects. Typically, lead time and WIP have reduced by about 50%.

• 한국생산제조학회지
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• 제7권1호
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• pp.95-103
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• 1998

This paper is concentraed on a study of operation for multiple objectives in a automated manufacturing system with multiple machining cells . Largest Sum Processing-time First(LSPF) was developed in order to minimize makespan, mean flowtime and maximize mean utilization and compare with Ho and Chang's algorithm(HC) and Hunsucker and Shah's algorithm(HS). The results show that LSPF provides better soutions than HC at 78.2% and than HS at 67.8% of total problems to frequency . LSPF reduces 5.8% of makespan by HC and 22.1% of the value by HS and curtails 15.8% , 7.5% of mean flowtime by receptive algorithms(HC, HS). And mean utilization is also higher about 5.5% than HC and HS.

• 한국정밀공학회지
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• 제9권4호
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• pp.36-43
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• 1992

This paper presents a hierarchical real-time operation control and monitoring scheme of the FMS/CIM center which has been implemented at the Automation and Systems Research Institute of Seoul National University. The hierarchical structure of the whole scheme consists of three lavers. The upper layer is in charge of on-line scheduling, computer network control, shop-floor monitoring and command generation for AGV dispatching, machining, assembly, inspection, set-up, etc. The middle layer has six modules, which are installed in the FMS host computer with the upper layer and run on the multi-tasking basis. Each module is connected to one of six cell controllers distributed in the FMS model plant and transfers operation command down to each cell controller through the Ethernet/TCP-IP local area network. The lower layer is comprised of six cell control software modules for machining cell, assembly cell, inspection cell, set-up stations. AS/RS and AGV. Each cell controller reports the status of the manufacturing facilites to the middle layer as well as ecxecuting the appropriate sequence control of the manufacturing processes.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.353-360
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• 2001

Electro Electric Systems Division of HHI is developing new series of models for industrial mid/compact size motors to satisfy the demand of costumers. Various essential technologies are required for motors to support design technology on design and development stage. Conventional motors have several things to analyze for mechanical strength and structural deformation during manufacturing process or operation. Therefore, the manufacturing cost will be reduced and the danger of accident during operation will be prevented by recognizing and revising the problems prior to actual manufacturing and operation. 112 Frame motor (3.7 kW) has been analyzed for this study and the basic analysis technology is eventually developed by analyzing other models gradually (sequence of 112, 135, 250, 200, 280, 225, 160, 180 Frame motors). Then, the developed technologies are established as main factors to support the motor design technology and competitive motors will be manufactured to satisfy the costumers.

• 산업공학
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• 제21권4호
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• pp.435-443
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• 2008

RFID (Radio Frequence Identification) is emerging technology and it is used for many fields. The research about RFID has been focused on hardware such as increasing hitting ratio. But recently the research about how and where RFID can apply is going on. Especially people are doing research about connecting RFID with existing information system. In this paper, when BPM manage RFID based manufacturing operation process, we show components which is needed and how we can obtain the components. And we apply this to straw manufacturing process on experiment. The claim-handling process and order-handling process which need improvement in straw manufacturing are chosen and we improve those processes. For executing the improved process, we define components which are database, data acquisition workflow and real-time event processing system and then we make prototype system.