• Title/Summary/Keyword: Unit System

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A study on evaluation of information retrieval system (정보검색(情報檢索)시스템의 평가(評価)에 관한 연구(硏究))

  • Park, In-Ung
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.5 no.1
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    • pp.85-105
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    • 1981
  • Information is an essential factor leading the rapid progress which is one of the distinguished characteristics in modem society. As more information is required and as more is supplied by individuals, governmental units, businesses, and educational institutions, the greater will be the requirement for efficient methods of communication. One possibility for improving the information dissemination process is to use computers. The capabilities of such machine are beginning to be used in the process of Information storage, retrieval and dissemination. An important problems, that must be carefully examined is whether one technique for information retrieval is better for worse than another. This paper examines problem of how to evaluate an information retrieval system. One specific approach is a cost accounting model for use in studying how to minimize the cost of operating a mechanized retrieval system. Through the use of cost analysis, the model provides a method for comparative evaluation between systems. The general cost accounting model of the literature retrieval system being designed by this study are given below. 1. The total cost accounting model of the literature retrieval system. The total cost of the literature retrieval system = (the cost per unit of user time X the amount of user time) + ( the cost per unit of system time X the amount of system time) 2. System cost accounting model system cost = (the pre-search system cost per unit of time X time) + (the search system cost per unit of time X time) + (the post search system cost per unit of time X time) 1) Pre-search system cost per unit of time = cost of channel per unit time + cost of central processing unit per unit time + cost of storage per unit time 2) Search system cost per unit of time = comparison cost + document representation cost. 3) Post-search system cost per unit of time. = cost of channel per unit time + cost of central processing unit per unit time + cost of storage per unit time 3. User cost accounting model Total user cost = [pre-search user cost per unit of time X (time + additional time) ] + [search user cost per unit of time X (time + additional time) ] + [post-search user cost per unit of time X (time + additional time) ].

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A Study on the Indoor Airflow Pattern by Changing the Location of Mechanical Terminal Unit (실내 급.배기구 위치변화에 따른 실 공기유동에 관한 연구)

  • Choi, Jeong-Min;Cho, Sung-Woo
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.3
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    • pp.193-200
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    • 2009
  • The ventilation system of apartments can be divided by supply and exhaust fan, supply fan and exhaust free and supply free and exhaust fan. Recently, the individual ventilation system and central ventilation system which is combined cooling system with duct system are applied to apartment ventilation system. The airflow pattern is affected by location of supply unit and exhaust unit in indoor. This study is to investigate the proper distance between supply unit and exhaust unit using CFD. As a result of this study, the proper distance between supply unit and exhaust unit could be suggested at the interval of 3 m in supply and exhaust fan system and 2.5 m in supply fan and exhaust free.

HVAC & Refrigeration System for Work Barge Vessel (WORK BARGE 선의 냉동.공조 SYSTEM)

  • Nam, Im-Woo;Jung, Jae-Chun;Kim, Bong-Je
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.583-590
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    • 2008
  • 최근 작업자 숙소 및 이송용 외에 작업용으로 사용 가능한 Barge선의 일종인 Accommodation Work Barge 선의 건조량이 증가 추세인 바 현재 중국에서 건조 중인 해당 선박의 HVAC & Refrigeration system에 대하여 정리하였다. 본 시스템은 R404A Direct expansion 냉각방식 (직접팽창방식)이 적용되었으며 HVAC system 중 Air conditioning 부분에 대해서는 선박의 각 Deck 기준으로 Zoning 하여 개별적인 Air handling unit와 Condensing unit를 구성하였으며 (각 unit의 용량은 필요용량의 100%), 냉동 창고의 Refrigeration system은 해당 격실 (육고, 어고, 야채고)에 각각 Unit cooler를 설치하고, Condensing unit를 기계실에 설치하였다. 장비는 전체 용량 100%에 대하여 항시 운전하는 100% 용량의 장비와 비상시에 운전하는 100% 용량의 예비 장비로 구성된다. 냉동 창고에 인접한 Dry provision store는 냉동 창고와는 별개로 중앙 공조기로부터의 냉각 공기를 이용하여 Spot cooling하였다. 본 System의 구성에 대한 장점 및 단점은 아래와 같다. 1. Air conditioning system이 각 Zone에 대하여 구성되므로 각 Zone에 대하여 제어가 가능하다. 2. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 냉매 배관의 길이가 짧다. 3. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 실내의 Maintenance space 상에 여유가 없다.

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Architecture design and FPGA implementation of a system control unit for a multiprocessor chip (다중 프로세서 칩을 위한 시스템 제어 장치의 구조설계 및 FPGA 구현)

  • 박성모;정갑천
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.12
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    • pp.9-19
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    • 1997
  • This paper describes the design and FPGA implementation of a system control unit within a multiprocessor chip which can be used as a node processor ina massively parallel processing (MPP) caches, memory management units, a bus unit and a system control unit. Major functions of the system control unit are locking/unlocking of the shared variables of protected access, synchronization of instruction execution among four integer untis, control of interrupts, generation control of processor's status, etc. The system control unit was modeled in very high level using verilog HDL. Then, it was simulated and verified in an environment where trap handler and external interrupt controller were added. Functional blocks of the system control unit were changed into RTL(register transfer level) model and synthesized using xilinx FPGA cell library in synopsys tool. The synthesized system control unit was implemented by Xilinx FPGA chip (XC4025EPG299) after timing verification.

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The Case Study on The Introduction and Practical Application of the Budget Management System -On the Performance Measurement of Standard Work Unit- (예산관리제도의 도입과 실제적 운용에 관한 사례연구 -표준적인 작업의 성과측정을 중심으로-)

  • 윤용운
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.2 no.2
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    • pp.39-51
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    • 1979
  • In introducing and applying the budget management system, the question of how to establish management structure(skelton) representing budget management responsible unit is significantly related to the degree of accuracy and analysis on the performance measurement of standard work unit. We have the following rational process of establishing performance measurement of budget management System ; 1) Standardization of work method 2) Establishment of management structure 3) Institution of budget management system. Especially, this system is based on a premise of efficiency of objectives management, it is assumed that performance measurement in the standard work unit must be enforced according to the basis and categories of performance evaluation based on the evaluating work unit. Therefore, most of all, the following three detail questions(subjects) are to be determined in order to rationalize these above principles to a maximum possible extent of performance measurement system. First, we established respective performance standard unit with respect to such detailed work unit, performance standard unit of which were accurately applicable directly from using the budget ana objectives account data and their supplementary data of the work measurement techniques. Second, by using the above mentioned question, over all evaluation and suggestion are made based on the study of the recording for each work unit development, budget management and production nit (volume of production) Third, the measurement of performance of budget management system is based on the principle of standard work unit, compared with the standard basis and actual work unit by period and activities unit and calculated percentage effectiveness according to the above procedure. and so evaluated the efficiency of performance measurement on the budget management system.

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Development of 100 Kw Power Class Airborne Auxiliary Power Unit (100 Kw급 항공용 보조동력장치(APU) 개발)

  • Yang, Soo-Seok;Lee, Dae-Sung;Kim, Seung-Woo
    • 유체기계공업학회:학술대회논문집
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    • 1999.12a
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    • pp.291-300
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    • 1999
  • Currently under development is an airborne auxiliary power unit with 100 Kw equivalent power, which is composed of a centrifugal compressor, a reverse annular combustor, and a radial turbine. Air-foil bearings are used in this power unit to eliminate the oil supplying system, which can reduce the system complexity and weight. The high speed generator is adopted as an electric power generation and engine starting system, which can also eliminate the reduction gear system. Not only electric power but also pneumatic power is provided by bleeding the compressed air This power unit is aimed for the multi-purpose use such as a primary power unit In the army weapon system, an auxiliary power and environmental control unit in a next-generation tank, and a smoke generating unit.

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The Development of Hemodialysis System Based on Embedded System (임베디드 시스템 기반의 혈액 투석기 시스템의 개발)

  • Ji, Jung-Ho;Lee, Kyoung-Joung;Kim, Young-Ho;Park, Kwang-Li
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.11
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    • pp.521-527
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    • 2002
  • The Hemodialysis system is the device for the patients who have suffered from end stage renal failure as the kidney which removes the waste products in a human body. The existing hemodialysis is based on a 8-bit micro-controller and it is not a touch-screen type but a manual type. This paper is focused on hemodialysis system based on high control and expension embedded system. The whole system consists of main control unit and sub control unit(dialysis control unit, blood control unit, monitoring control unit, networking unit). The dialysis control unit, blood control unit, monitoring control unit are processed by 3 microcontrollers and network unit is for monitoring a renal failure patient's condition. For the evaluation of the system performance, the saline was pured into blood unit and then water removal rate, conductivity and temperature of hemodialysis liquid were measured 10 times in an each state suing the UF pump in the fluid unit varing the quantity of saline to 1000cc, 2000cc, 3000cc and 4000cc. As a result, the rates of water removal are 98.6% in condition of 000cc saline, 96.9% in 2000cc, 98.9% in 3000cc and 98.3% in 4000cc. The conductivities of hemodialysis liquid are 99.6% in the first to third condition and 99.7% in the forth condition. The temperatures of hemodialysis liquid are 99.8% in the first to third condition and 99.6% in th forth condition.

A Study on the Development of Unit Catalog System for Curriculum Linkage in School Libraries: Focusing on Middle School Science Department (교과연계를 위한 학교도서관 단원목록 시스템의 개발에 관한 연구 - 중학교 과학과를 중심으로 -)

  • Bolan, Kim;Jeong-Hyen, Kim
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.33 no.4
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    • pp.27-47
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    • 2022
  • The purpose of the study is to develop a unit catalog system that can be linked with the curriculum. As for the research method, first, unit subject words were extracted through the analysis of middle school curriculum and science textbooks in all grades. Based on this, we designed a unit catalog system that has a unit book catalog by connecting books related to the unit topic of the subject, an index word catalog that organizes unit subject words into index words, and a grade and school level linked subject linked to the unit topic as a subsystem. Using the Notion program, a unit catalog system was implemented on the web using a middle school science unit 1 as a sample. To evaluate the system, experiments and surveys were conducted targeting students, and very positive results were shown in terms of satisfaction with the system and intention to use it in the future. Meanwhile, this study was limited to middle school science departments, but it was proposed to expand the application to all grades and subjects.

FUZZY CONTROL SYSTEM in PLC (PLC에서의 FUZZY CONTROL SYSTEM의 구현)

  • Lee, Y.J.;Ryou, J.S.;Song, S.W.;Park, S.B.;Hong, J.S.
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.895-897
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    • 1995
  • As PLC has become cetral to today's FA environment, the importance of developing and providing special-unit of PLC such as Analog-unit, PID-unit, Fuzzy-unit has increased. In this paper introduce the Fuzzy-unit which is developed by LGIS R&D lab, and presents availability of PLC-control system with fuzzy-unit.

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The Design of an Automatic System for Dairy Cattle Breeding I - The Choice of Temperature Sensor for Body Temperature Measuring - (낙농의 자동화 시스템 구성 I - 체온 감지 온도센서의 선정 -)

  • 김형주;정길도;한병성;김용준;김동원;김명순
    • Journal of Biosystems Engineering
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    • v.23 no.1
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    • pp.83-90
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    • 1998
  • In this paper the automatic system for dairy cattle has been desisted such as body temperature measuring unit, feed supplying unit and temperature control unit. Since e disease is strongly related to the body temperature of cattle, early detection of the abnormal temperature would prevent the severe problems which nay occur in dairy farms. An electronic component AD590J is used as temperature sensor for the system, The device is highly robust against the noise since the output signal is the current so it can be applied to a long distance sensing The resolution of signal is 0.1$^{\circ}C$ and the current is 10㎷ Also 12-bit A/D converter is desisted fir interfacing the sensor with a one-chip microprocessor. A temperature measuring experiment using the developed system has been done for measuring the temperature of human beings and the system was proven to be useful for measuring the body temperature of dairy cattle properly. A geared AC motor is used for the feed supplying unit The heater and fm are used as temperature control unit. The feed supplying unit and temperature control unit are well operating in the laboratory experiment.

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