• 대한산업공학회지
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• 제41권2호
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• pp.173-184
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• 2015

The application of radio frequency identification (RFID) sensor-tags in cold chain systems has recently received a great deal of attention. To design cold chain systems with RFID sensor-tags that minimize the initial investment and operational cost while fulfilling the functional and operational requirements, simulation study is one of the preferable and effective approaches. To simulate the possible design configurations, the individual components in a cold chain system can be extracted and implemented as a DEVS (Discrete Event System Specification) model. Based on the proposed DEVS model, a new cold chain simulation model can be efficiently created by simply connecting each DEVS model around the RFID sensor-tag of interest in sequence according to the structure of the cold chain system, and then executed (or simulated) on Java programming environments by the DEVSJAVA simulator. As a result of simulation, some key performance indexes such as reliability, accuracy or timeliness can be calculated and used to choose better components or to compare different system configurations of cold chain systems.

• 유통과학연구
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• 제12권11호
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• pp.5-13
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• 2014

Purpose - This study traces the determinants of key account management performance in the garments industry in Bangladesh. The key account management approach involves significant challenges for marketers to manage their strategically important customers and use this approach as a strategic weapon in their selling efforts. This study examines three categories of determinants of key account management performance including operational variables, organizational variables, and relational variables by exploring data from 100% export oriented readymade garments companies in Bangladesh. Research design, data, and methodology - Data were collected from 30 readymade garments manufacturers, considering a company as a unit of analysis. Using the data, instrument validity and reliability and, subsequently, data normality were examined using the Statistical Package for the Social Sciences (SPSS) software to isolate the important determinants of key account management performance. Results - The instruments are reliable and the data are reasonably normal. Conclusion - The study explored and validated the adapted instruments of various operational, organizational, and relational antecedent factors of key account management performance, most of which were thus far ignored.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.147-154
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• 2008

A simulation program is developed for the optimal design of small scale district heating and cooling system. Main features for the simulation program are the reliability and the easiness for the optimal design of the DHC(District Heating and Cooling) systems. In order for implementing those features, the operational characteristics according to the prime movers is modeled based on the materials of efficiency as a function of operational load. The unit energy load model is also developed extensively for several building types, of which the corresponding district consist, such as apartment complex, hotel, hospital, buildings for business and commercial use respectively. The specific features and the overall procedure of the simulation are described in brief in this paper. The results of the simulation for several test cases will be presented in subsequent study.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.165-170
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• 2001

An extensive range of pumping facilities are employed in the regional water supply system in metropolitan areas, and optimization and the systematic combination of the Pump facilities have direct bearing on the stability and economy of the water supply system concerned. These systems must be able to guarantee stability, efficiency and offer high reliability. Preparation of metropolitan area regional water supply system construction project must include a basic plan which takes into account the suitability of pumping facilities to be used, the environment in which facilities will be installed, man-power requirements and basic operational and management policies. This paper contains over-all analysis of the management of metropolitan area regional water supply systems as like Jayang, Paldang 1st pump station. In the study, it aims to prepare counterplan which will be operated and managed the pump upon the operational conditions and to suggest the proposal for water facilities codes to decides total head of pump in Korea.

• 한국전자파학회논문지
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• 제10권1호
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• pp.11-21
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• 1999

AICPS(Advanced Information Communication System)는 다양한 서비스망들을 고속으로 지원하기 위하 여, 내부의 연동망인 고속스위칭패브릭(High Speed Switching Fabric: HSSF)을 중심으로 다양한 서비스 인터페이스 기능 모률이 접속되는 형태를 가진다. AICPS는 크게 정보 서비스 이용자들이 접속되는 서비스 이용자 접속 시스댐(User Access Network Subsystem: UANS) , 정보 제공 센터들을 위한 정보 제공 센터 접속 시스템(Information Delivery Network Subsystem : IONS)으로 구성되며, 여기에 시스템 관리를 위한 단위 시스템 운영관리장치(Local Operations and Management System : LOMS)가 접속된다. 본 고에서는 AICPS를 운영 관리하는 LOMS, LOMS를 AICPS의 HSSF와 연결하기 위한 관리망 접속 서브시스템 (Operational Network Ace랭 Subsystem: ONAS)의 구조에 대하여 설명하고, 이들 사이에 적용된 신뢰도 향상 알고리즘 및 전국 관리망 구축 방법에 대하여 기술한다.

• 한국생산제조학회지
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• 제24권6호
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• pp.660-666
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• 2015

To avoid radiation exposure from repeated x-rays taken during orthopedic surgery, an x-ray permeable teleoperated Stewart platform for orthopedic fracture surgery was developed. This system is composed of a user interface device and a teleoperated operational robot, both of which use a Stewart platform mechanism. The links of the operational robot are made from an x-ray permeable material, polycarbonate, to minimize the interference. The forward and inverse kinematics algorithm applied and the structural reliability were both verified through an analysis using commercial engineering software. To monitor the operating status in real time and stop the device during an emergency, a monitoring software was developed. The performance of the x-ray permeable teleoperated Steward platform was validated experimentally.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.825-832
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• 2008

A simulation program is developed for analysing thermal networking process between the District heating and the CES(Community Energy Supply) systems. The effects of thermal networking on the District heating facilities previously being operated are implemented using mathematical correlations in terms of the fuel consumption and energy load such as heating and electricity. The operational characteristics according to the prime movers is modeled based on the materials of efficiency as a function of operational load. The unit energy load model is also developed extensively for several building types such as apartment complex, hotel, hospital, buildings for business and commercial use respectively. The specific features of the newly developed program in simulation of thermal networking process in district heating is described in terms of the reliability and the easiness for operating it etc.

• 한국전기전자재료학회논문지
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• 제19권6호
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• pp.507-511
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• 2006

We investigated accelerated soft error rate (ASER) in static random access memory (SRAM) cells of thin film transistor (TFT) type. The effects on ASER by cell density, buried nwell structure, operational voltage, and polysilicon-2 layer thickness were examined. The increase in the operational voltage, and the decrease in the density of SRAM cells, respectively, resulted in the decrease of ASER values. The SRAM chips with buried nwell showed lower ASER than those with normal well structure did. The ASER decreased as the test distance from alpha source to the sample increased from $7{\mu}m\;to\;15{\mu}m$. As the polysilicon-2 thickness increased up to $1000\;{\AA}$, the ASER decreased exponentially. In conclusion, the best condition for low soft error rate, which is essential to obtain highly reliable SRAM device, is to apply the buried nwell structure scheme and to fabricate thin film transistors with the thick polysilicon-2 layer

• Smart Structures and Systems
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• 제12권2호
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• pp.209-233
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• 2013

With an annual growth rate of about 30%, wind energy systems, such as wind turbines, represent one of the fastest growing renewable energy technologies. Continuous structural health monitoring of wind turbines can help improving structural reliability and facilitating optimal decisions with respect to maintenance and operation at minimum associated life-cycle costs. This paper presents an integrated monitoring system that is designed to support structural assessment and life-cycle management of wind turbines. The monitoring system systematically integrates a wide variety of hardware and software modules, including sensors and computer systems for automated data acquisition, data analysis and data archival, a multiagent-based system for self-diagnosis of sensor malfunctions, a model updating and damage detection framework for structural assessment, and a management module for monitoring the structural condition and the operational efficiency of the wind turbine. The monitoring system has been installed on a 500 kW wind turbine located in Germany. Since its initial deployment in 2009, the system automatically collects and processes structural, environmental, and operational wind turbine data. The results demonstrate the potential of the proposed approach not only to ensure continuous safety of the structures, but also to enable cost-efficient maintenance and operation of wind turbines.

• 한국컴퓨터정보학회논문지
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• 제24권6호
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• pp.99-107
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• 2019

With the development of various types of military Unmanned Aircraft(UA)s, the need for interworking and integration between different platforms gradually increased. In order to ensure interoperability at each military UA System(UAS) level, North Atlantic Treaty Organization(NATO) has established STANAG-4586 "Standard Interfaces of Unmanned Aircraft(UA) Control Systems(UCS) for NATO UA Interoperability-Interface Control Document". This paper looks at the basic design structure of STANAG-4586 and the changes on Edition 4 to enhance joint operational capability through reflecting and updating the interoperability design of the military UAS. In particular, we analyze the enhanced Datalink Transition/Handover Procedure and Autonomous functions, one of the biggest features added to the edition. Through this, we propose a modification of UA data link exclusive control using UA Bypass structure, which was impossible in the one-to-one communication structure between existing UA and Core UCS(CUCS). We also suggest ways to improve UA operational reliability by applying Autonomous Functions that directly decides how to deal with emergency situations, rather than by a remote operator over CUCS.