• Title/Summary/Keyword: IT Vendor

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A Development of PC/Ethernet based Fieldbus Network for Large Realtime Data Communication

  • Gwak, Kwi-Yil;Lee, Sung-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.362-367
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    • 2005
  • Control network adopted in the national power-plant or manufactory are mostly vendor-dependent products, which have their own special specification, components and individual communication methods. These systems not only raise installation cost, but also bring many difficulties to maintenance and extension. To overcome these problems, this paper introduces a development and application case of a new "PC/Ethernet-based fieldbus" architecture and protocol to be used in mid-level fieldbus. The designed system has a basic idea of "3 Layers fieldbus over Standard-LAN" and implemented on PCs. PC gives user friendly environment. By using an open standard Ethernet in layer 1,2, the system has low cost, wide communication bandwidth and high compatibility. Layer 3 protocol designed for large realtime data communication makes user bypass TCP/IP layer and gives user direct access to the Ethernet. This new protocol eliminates potential collision of Ethernet, and transmits large periodic/non-periodic control data by using long-frame/wide-bandwidth of Ethernet effectively, and offers simple API-Services to the upper layer. Since the system have installed in H-power plant simulator and U-nuclear power plant simulator in Korea, it have been proved to be efficient and stable without any trouble in realtime communication service for full-scope plant simulator that has a lot of control elements.

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Applying Theory of Constraint on Logistic Management in Large Scale Construction Sites - A Case Study of Steel Bar in TFT-LCD Factory Build-Up

  • Huang, Chih-Yao;Chen, Ching-Piao;Li, Rong-Kwei;Tsai, Chih-Hung
    • International Journal of Quality Innovation
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    • v.9 no.1
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    • pp.68-93
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    • 2008
  • The steel bars account for a high percentage of material costs for the current construction projects. At the present time, most of the construction projects for the factories of thin-film transistor liquid crystal display (TFT-LCD) complete the transactions of steel bars when the suppliers ship the steel bars to the temporary storage/processing sites. This paper applies the buy-in concept in the Theory of Constraint (TOC) on the supply chain of steel bars. In this study, suppliers are required to establish warehouses at the construction sites and complete the transactions when the formed and processed steel bars are shipped into the factory sites. The aim is to find a win-win solution to meet with the expectations from constructors as they hope that there is no need to build up inventories but supply is ready at any time. Also, this paper compares and analyzes the traditional supply/inventory model of steel bars and the Demand-Pull (D-P) model under the TOC framework. It is proved that Vendor Management Inventory (VMI) in the D-P model is able to more effectively manage steel bars as a material.

A Study on the Dress Form for the Making Dresses: Focusing on the Size Cover Rate and Correction (드레스 제작을 위한 인대 연구: 사이즈 커버율과 보정을 중심으로)

  • Lee, Sanghee;Kwon, Sookhee
    • Human Ecology Research
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    • v.58 no.2
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    • pp.215-228
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    • 2020
  • Underlying dress forms for high coverage patterns are very important in the dress industry. Size 9 from brand D was chosen according to the analysis that it was the best option because a dress should have a large allowable range in one size. The criteria for selection were the dress form with a waist circumference of 63.50 centimeters, which is close to the standard size of women in Korea. Brassieres for dresses were included to enhance the aesthetic value of the correction process in producing a basic dress pattern. An experimental torso pattern was applied to evaluate the fit and suitability of the dress form that was also later verified in the process of the dress works. Three dresses were produced and presented on the chosen study dress form. The research procedures are as follows. First, the sell-through rates and feedbacks were collected from the dress form vendor. Second, a literature survey on dresses and a dress company investigation were conducted. Third, the amount of body dimension changes due to the use of a bra in the dresses were examined. Fourth, after the correction of the dress form, the torso pattern was made by draping. Fifth, the torso experimental clothing made of muslin material was evaluated. Sixth, the dress works of the top design were presented using the size 9 basic pattern developed by brand D.

A Case Study on Diagnosis and Checking for Machine-Tools with an OAC (개방형 컨트롤러를 갖는 공작기계에 적합한 진단 및 신호점검사례)

  • 김동훈;송준엽;김경돈;김찬봉;김선호;고광식
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.10a
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    • pp.292-297
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    • 2004
  • The conventional computerized numerical controller (CNC) of machine tools has been increasingly replaced by a PC-based open architecture CNC (OAC) which is independent of the CNC vendor. The OAC and machine tools with OAC led the convenient environment where it is possible to implement user-defined application programs efficiently within CNC. Tis paper proposes a method of operational fault cause diagnosis which is based on the status of programmable logic controller (PLC) in machine tools with OAC. The operational fault is defined as a disability state occurring during normal operation of machine tools. The faults are occupied by over 70% of all faults and are also unpredictable as most of them occur without any warning. Two diagnosis models, the switching function (SF) and the step switching function (SSF), are propose in order to diagnose the fault cause quickly and exactly. The cause of an occurring fault is logically diagnosed through a fault diagnosis system (FDS) using the diagnosis models. A suitable interface environment between CNC and develope application modules is constructed in order to implement the diagnostic functions in the CNC domain. The diagnosed results were displayed on a CNC monitor for machine operators and provided to a remote site through a web browser. The result of his research could be a model of the fault cause diagnosis and the remote monitoring for machine tools with OAC.

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CNC-implemented Fault Diagnosis and Web-based Remote Services

  • Kim Dong Hoon;Kim Sun Ho;Koh Kwang Sik
    • Journal of Mechanical Science and Technology
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    • v.19 no.5
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    • pp.1095-1106
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    • 2005
  • Recently, the conventional controller of machine-tool has been increasingly replaced by the PC-based open architecture controller, which is independent of the CNC vendor and on which it is possible to implement user-defined application programs. This paper proposes CNC­implemented fault diagnosis and web-based remote services for machine-tool with open architecture CNC. The faults of CNC machine-tool are defined as the operational faults occupied by over $70{\%}$ of all faults. The operational faults are unpredictable as they occur without any warning. Two diagnostic models, the switching function and the step switching function, were proposed in order to diagnose faults efficiently. The faults were automatically diagnosed through the fault diagnosis system using the two diagnostic models. A suitable interface environment between CNC and developed application modules was constructed for the internal function of CNC. In addition, a suitable web environment was constructed for remote services. The web service functions, such as remote monitoring and remote control, were implemented, and their operability was tested through the web. The results obtained through this research could be a model of fault diagnosis and remote servicing for machine-tool with open architecture CNC.

A Feasibility Study on the Outsourcing of Cataloging in the Libraries (목록 아웃소싱의 타당성 분석에 관한 연구)

  • Chung Hye-Kyung
    • Journal of the Korean Society for Library and Information Science
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    • v.39 no.2
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    • pp.35-55
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    • 2005
  • This study attempts feasibility analysis of cataloging outsourcing. The economic analysis model based on information economics categorizes the benefit into direct benefit and value linking. We measure direct benefit by cost savings and cost avoidance, value linking by the degree of improvement in cataloging quality The results show that there is no feasibility overall, because librarians spent more time to control the quality due to vendor's lack of professionalism, resulting little effect on cost savings. When cataloging outsourcing is forcibly used under the economically infeasible condition, it is impossible to achieve the basic purpose of operating cost savings and improvement of service function.

Factors Affecting the Conflicts in the Outsourced Information System Development (정보시스템 아웃소싱 개발에 따른 갈등 영향 요인)

  • Cho, Dong-Hwan;Choi, Hun
    • The Journal of the Korea Contents Association
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    • v.10 no.12
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    • pp.342-351
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    • 2010
  • This study aims to investigate the major causes of conflict between clients and vendors in the outsourced IS development. A research model is established based on the prior research of IS outsourcing, system development and conflict. An empirical study was executed using 214 survey questionnaire of project teams composed of client and vendor with PASW 18.0. Research results using multiple regressions show that contract specificity, requirements certainty, objective alignment and client knowledge have negative effects on conflict. This research results will provide various implications for outsourcing project success.

Improved Photovoltaic MATLAB Modeling Accuracy by Adding Wind Speed Effect

  • An, Dong-Soon;Poudel, Prasis;Bae, Sang-Hyun;Park, Kyung-Woo;Jang, Bongseog
    • Journal of Integrative Natural Science
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    • v.10 no.1
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    • pp.58-63
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    • 2017
  • Photovoltaic (PV) are generally modeled using mathematical equations that describe the PV system behavior. Most of the modeling approach is very simple in terms of that PV module temperature is calculated from nominal constant cell temperature such as ambient temperature and incoming solar irradiance. In this paper, we newly present MATLAB model particularly embedding the effect of wind speed to describe more accurate cell temperature. For analyses and validate purpose of the proposed model, solar power is obtained and compared with and without wind speed from the 50Wp PV module provided by vendor datasheet. In the simulation result, we found that power output of the module is increased to 0.37% in terms of cell temperature a degreed down when we consider the wind speed in the model. This result is well corresponded with the well-known fact that normal PV is 0.4% power changed by cell temperature a degree difference. Therefore it shows that our modeling method with wind speed is more appropriate than the methods without the wind speed effect.

Performance Evaluation of Switched Ethernet for Real-time Industrial Communication (실시간 산업용 통신을 위한 Switched Ethernet의 성능 평가)

  • Lee, Kyung-Chang;Kim, Tae-Jun;Lee, Seok
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.1
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    • pp.90-98
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    • 2003
  • The real-time industrial network, often referred to as fieldbus, is an important element for building automated manufacturing systems. Thus, in order to satisfy the real-time requirements of field devices, numerous fieldbus protocols have been announced. But the application of fieldbus has been limited due to the high cost of hardware and the difficulty in interfacing with multi-vendor products. Therefore, as an alternative to fieldbus, the computer network technology, especially Ethernet (IEEE 802.3), is being adapted to the industrial environment. However, the crucial technical obstacle for Ethernet is its non-deterministic behavior that makes it inadequate for industrial applications where real-time data have to be delivered within a certain time limit. Recently, the development of switched Ethernet shows a very promising prospect for industrial application due to the elimination of uncertainties in the network operation resulting in much improved performance. This paper focuses on the application of the switched Ethernet for industrial communications. More specifically, this paper presents an analytical and experimental performance evaluation of the switched Ethernet and a case study about networked control system.

A study on the status and support policies of the small wholesale vendor in Korea

  • Lee, Sang-Youn
    • East Asian Journal of Business Economics (EAJBE)
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    • v.4 no.4
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    • pp.24-32
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    • 2016
  • There hardly have been support policies for small wholesale vendors or any materials such as proper statistical standards and figures compared to diversity of support policies and size of budget for small and medium manufacturing business. The biggest concern coming from it is that there have never been any policies for small and medium wholesale vendors. This study proposes some ways to improve support policies through investigating the current status of those vendors as their true values haven't been properly recognized, while diverse support systems have been devised for manufacturing business thanks to the traditional industrial development process. According to the study on support policies for domestic and international small and medium wholesale vendors, I realized that those vendors need a policy to ensure them to be promptly adjusted to the rapidly changing distribution environment and to be competitive to access to the global distribution market to finally become hidden champions through systematical operations of small and medium wholesale vendors and implementing educational business through sales management. Therefore, I propose five ways to improve support policies for small and medium wholesale vendors by considering social and economic value, systematizing small wholesalers and scaling small and medium wholesale vendors, reinforcing support for wholesalers, support policies for new online market opening and offline market opening.