• Title/Summary/Keyword: operation condition

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The simulation study on natural circulation operating characteristics of FNPP in inclined condition

  • Li, Ren;Xia, Genglei;Peng, Minjun;Sun, Lin
    • Nuclear Engineering and Technology
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    • v.51 no.7
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    • pp.1738-1748
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    • 2019
  • Previous research has shown that the inclined condition has an impact on the natural circulation (natural circulation) mode operation of Floating Nuclear Power Plant (FNPP) mounted on the movable marine platform. Due to its compact structure, small volume, strong maneuverability, the Integral Pressurized Water Reactor (IPWR) is adopted as marine reactor in general. The OTSGs of IPWR are symmetrically arranged in the annular region between the reactor vessel and core support barrel in this paper. Therefore, many parallel natural circulation loops are built between the core and the OTSGs primary side when the main pump is stopped. and the inclined condition would lead to discrepancies of the natural circulation drive head among the OTSGs in different locations. In addition, the flow rate and temperature nonuniform distribution of the core caused by inclined condition are coupled with the thermal hydraulics parameters maldistribution caused by OTSG group operating mode on low power operation. By means of the RELAP5 codes were modified by adding module calculating the effect of inclined, heaving and rolling condition, the simulation model of IPWR in inclined condition was built. Using the models developed, the influences on natural circulation operation by inclined angle and OTSG position, the transitions between forced circulation (forced circulation) and natural circulation and the effect on natural circulation operation by different OTSG grouping situations in inclined condition were analyzed. It was observed that a larger inclined angle results the temperature of the core outlet is too high and the OTSG superheat steam is insufficient in natural circulation mode operation. In general, the inclined angle is smaller unless the hull is destroyed seriously or the platform overturn in the ocean. In consequence, the results indicated that the IPWR in the movable marine platform in natural circulation mode operation is safety. Selecting an appropriate average temperature setting value or operating the uplifted OTSG group individually is able to reduce the influence on natural circulation flow of IPWR by inclined condition.

A Study on the Opimization of Process and Operation Condition for Membrane System in Tap Water Treatment (분리막을 이용한 정수처리 System에서 처리공정 및 운전조건의 최적화에 관한연구)

  • 오중교
    • Membrane Journal
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    • v.9 no.4
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    • pp.193-201
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    • 1999
  • The object of study were the development of membrane process and the optimization of operation condition for membrane system, which was used the pre-treatment system of tap water treatment in steady of conventional process such as coagulation, sedimentation. The higher steady flux is very important factor, by a suitable pre-treatment and optimization of operating condition such as fouling control, crossflow and backwashing method, in membrane system. So, we were observed the effect of flux decline for membrane used by 4 type ultrafiltration(UF) membrane pre-treatment process, and optimized the operation condition of filtration system under various MWCO(Molecular weight cut-off), operation pressure, linear velocity and temperature to maintain higher flux. From these experiment, we were identified that UF process showed a slower flux decline rate and a higher flux recovery than microfiltration(MF) membrane. The water quality of UF permeate was better than that of MF, and was not effected pre-treatment process. In the operation condition, the rate of flux decline was diminished by a higher linear velocity and operation temperature, lower pressure.

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Anticorrosive Monitoring and Complex Diagnostics of Corrosion-Technical Condition of Main Oil Pipelines in Russia

  • Kosterina, M.;Artemeva, S.;Komarov, M.;Vjunitsky, I.;Pritula, V.
    • Corrosion Science and Technology
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    • v.7 no.4
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    • pp.208-211
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    • 2008
  • Safety operation of main pipelines is primarily provided by anticorrosive monitoring. Anticorrosive monitoring of oil pipeline transportation objects is based on results of complex corrosion inspections, analysis of basic data including design data, definition of a corrosion residual rate and diagnostic of general equipment's technical condition. All the abovementioned arrangements are regulated by normative documents. For diagnostics of corrosion-technical condition of oil pipeline transportation objects one presently uses different methods such as in-line inspection using devices with ultrasonic, magnetic or another detector, acoustic-emission diagnostics, electrometric survey, general external corrosion diagnostics and cameral processing of obtained data. Results of a complex of diagnostics give a possibility: $\cdot$ to arrange a pipeline's sectors according to a degree of corrosion danger; $\cdot$ to check up true condition of pipeline's metal; $\cdot$ to estimate technical condition and working ability of a system of anticorrosive protection. However such a control of corrosion technical condition of a main pipeline creates the appearance of estimation of a true degree of protection of an object if values of protective potential with resistive component are taken into consideration only. So in addition to corrosive technical diagnostics one must define a true residual corrosion rate taking into account protective action of electrochemical protection and true protection of a pipeline one must at times. Realized anticorrosive monitoring enables to take a reasonable decision about further operation of objects according to objects' residual life, variation of operation parameters, repair and dismantlement of objects.

The Relay Circuits Translation to EMFGs (릴레이 회로의 확장된 마크흐름선도 변환)

  • 여정모;백형구
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.11
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    • pp.952-957
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    • 2003
  • We propose how to translate relay circuits to the EMFGs(Extended Mark Flow Graphs) formally and analyze the original one by using the mark flow of it. Firstly, the concepts of the output condition, the output-on condition and the output-off condition are introduced in the relay circuits. These can be used to find the structure and the operation of respective relay outputs but the sequential operations of them cannot be obtained from these. Secondly, a relay circuit is translated to the corresponding EMFG as the all output-on conditions and all output-off conditions of it are translated to EMFGs. For the adequate translation, the condition arc and the concepts of the generation transition and the degeneration transition are introduced, and the duality for the simplification of the result. Thirdly, we analyze the operation of the original circuit by analyzing the mark flow of the resulting EMFG. We can achieve easy and fast analysis based on the EMFG's operation algorithm. Finally, we apply these to the relay circuit for an electric furnace and analyze its operation with the mark flow of the resulting EMFG. The formal translation from relay circuits to EMFGs makes the analysis easy so that these results can be used to design, modelling, the fault detection and the maintenance.

Analysis of Engine Operation Condition by Using Coastdown Test under Gear Engaged Condition (기어 물림 상태의 타행 주행 저항을 이용한 엔진 운전 조건의 분석)

  • Shim, Beom-Joo;Park, Kyoung-Suk;Park, Jun-Su;Min, Byeong-Du
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.6
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    • pp.61-66
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    • 2012
  • Conventional method to transform vehicle driving condition to engine operation mode is to use vehicle road load under neutral gear and mechanical efficiency of drivetrain. But this method requires additional measurement of efficiency of drivetrain on a test rig. And this measurement is normally done at fixed speed and thus estimated accuracy of engine operation mode is not considered to be high enough. This study suggests new method to calculate engine operation mode for prescribed driving mode such as NEDC using vehicle coastdown test under gear engaged condition without measurement of mechanical efficiency of drivetrain. Coastdown test was done under neutral and gear engaged condition for comparison and also trial to extract mechanical loss of drivetrain was carried out. Calculated engine torque by conventional and newly suggested method was compared with actually measured torque of a vehicle on a chassis dynamometer during NEDC. Newly suggested method showed slightly higher accuracy of accumulated brake work during NEDC.

A Study of Operation Performance Prediction Method for the Gasification Melting Furnace (가스화 용융로의 운전성능 예측기법에 관한 연구)

  • Lee, Min-Do;Choi, Sang-Min
    • 한국연소학회:학술대회논문집
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    • 2005.10a
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    • pp.43-49
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    • 2005
  • Social interest and request about low pollution waste treatment process are growing and gasification melting method, as a new technology concept, is risen. The necessity of engineering analysis to determine design standards and operation condition is required. In this study, the objective and function of components and operation process of various gasification melting furnaces such as shaft type, fluidized bed and Rotary Kiln type gasification melting furnace are reviewed and the design standard and operation range of gasification melting furnace are determined by inspecting the change of output and operation condition with input condition change.

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A Study in the Directory Service Protocol in Distributed Environment (분산환경에서의 디렉토리 서비스 프로토콜에 관한 연구)

  • Lee, Jie-Young
    • The Journal of Information Technology
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    • v.9 no.3
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    • pp.59-66
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    • 2006
  • This paper proposes directory service protocol in distributed environment. By adding an condition retrieval function to Modify operation, the ExtModify operation improves the inconvenience to transfer a search operation and resume a Modify operation. The method suggests how to correct all the entries which require retrieval condition out of other entries designated by LDAPND.

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A Study on Maintenance Actual Condition and Revitalization of Rural Development Project (일반농산어촌개발사업 완료지구 시설물 실태분석 및 활성화 방안 연구)

  • Choi, Young-Wan;Kim, Keun-Ho;Eun, Hee-Chang;Lee, Young-Kyu;Kim, Young-Joo
    • Journal of Korean Society of Rural Planning
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    • v.22 no.2
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    • pp.1-8
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    • 2016
  • This study is intended to prepare an revitalization plan of region where rural development project is completed through an analysis of the actual condition of facility operation and maintenance in the region where the project is completed. The results of survey of actual condition of facility operation in the region where rural development project was completed showed that the facilities were not self-sufficient in terms of operation and maintenance cost. Therefore, a prerequisite to the revitalization of region where the project is completed is to prepare an alternative plan for increasing the efficiency and applicability of currently already prepared facilities. Second, a project operation organization system should be streamlined and the competency of operation personnel should continue to be strengthened. Third, it is necessary to prepare a support system and establish cooperation networks for increasing the extensibility of project and continuing to induce community revitalization in the region where the project is completed in the future.

The present condition comparative analysis the case of Bakery In Luxurious Hotels (특 1급호텔 베이커리의 현황 비교 분석)

  • 이진
    • Journal of Applied Tourism Food and Beverage Management and Research
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    • v.16 no.2
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    • pp.153-173
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    • 2005
  • The purpose of a study was the present condition comparative analysis by the case of Bakery in Hotels. The sample was selected first grade hotels in seoul. The method of research was In-depth interview. The questionee were mamagers and chefs each hotel bakery. Interview was accomplished average 45minutes. The period of the research was from 1th of Februrary, 2002 to 28th of February, 2002. The survay was composed of product operation, employee operation, equipment operation, customer operation, sales and bakery characteristics. the data was analyized by SPSS10.0 mean, maximum value and minimum value were salected. Recently, as it is getting higher of importance of bakery in the food service market and many major companies run into a bakery industry, the researches about bakery have advanced, however in fact, materials or researches about hotel bakery are fewer than franchise, in-store bakery and mass production enterprise. Especially, each hotel exchanges their information through benchmarking but data analysis - accurate materials, sales, the present condition equipment is not easy to perform. The purpose of this study was to be helpful for studying hotel bakery for others by analysis. The data was analyzed by each hotel characteristics, employee, equipment, sales, productions and the present condition sales.

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The present condition comparative analysis the case of Bakery in Luxurious Hotels (특 1급호텔 베이커리의 현황 비교 분석)

  • Lee, Jin
    • Proceedings of the Korea Hospitality Industry Research Society Conference
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    • 2005.11a
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    • pp.92-108
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    • 2005
  • The purpose of a study was the present condition comparative analysis by the case of Bakery in Hotels. The sample was selected first grade hotels in seoul. The method of research was In-depth interview. The questionee were mamagers and chefs each hotel bakery. Interview was accomplished average 45minutes. The period of the research was from 1th of Februrary, 2002 to 28th of February, 2002. The survay was composed of product operation, employee operation, equipment operation, customer operation, sales and bakery characteristics. the data was analyized by SPSS10.0 mean, maximum value and minimum value were salected. Recently, as it is getting higher of importance of bakery in the food service market and many major companies run into a bakery industry, the researches about bakery have advanced, however in fact, materials or researches about hotel bakery are fewer than franchise. in-store bakery and mass production enterprise. Especially, each hotel exchanges their information through benchmarking but data analysis - accurate materials, sales, the present condition equipment is not easy to perform. The purpose of this study was to be helpful for studying hotel bakery for others by analysis. The data was analyzed by each hotel characteristics, employee, equipment, sales, productions and the present condition sales.

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