• Title/Summary/Keyword: Start-up Condition

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A Study on Information Literacy Education Program of Medical Library: Focused on C University Medical Library (의학도서관 정보이용교육 프로그램 연구: C대학교 의학도서관을 중심으로)

  • Lee, Yong-Jae;Woo, Sang-Hee
    • Journal of Information Management
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    • v.39 no.3
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    • pp.49-71
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    • 2008
  • This study aims to develop more user-oriented information literacy education for medical libraries in Korea. For this purpose, we benchmarked some advanced models in and out of Korea, and examined a case of C medical library which is medium size in Korea. Especially, we looked into the actual condition of information literacy education of C medical library and the information need of its users. We suggested some ideas to construct the programs for information literacy education of medical libraries in Korea. Especially, we proposed some considerations, contents and flow for the programs. The results of this study can be useful references whenever each medical library in Korea will start or make up for its information literacy program.

The Effects of the Type of Cereal Powder and Extruder Operation Conditions on the Barrel Temp.-distribution (원료곡분의 성상과 압출 조건이 Extruder 내부 온도분포에 미치는 영향)

  • Ryu, Gi-Hyung;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.20 no.3
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    • pp.303-309
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    • 1988
  • The heat generation at the start-up period of an autogeneous single screw extruder was determined with various feed materials, die structure and operational conditions. The highest heat generation rate was observed with defatted soybean meal, while the lowest value was obtained with rice flour, and wheat and barley flour showed the intermediate rate. As the moisture content of the flour decreased and the screw speed increased, the electric power requirement and heat generation rate increased. The temperature at compression section increased with the decrease in the particle size. The same effect was also observed as breaker plate was installed. The optimum operation was established as the temperature profile was maintained in decreasing order of metering section, die and compression section.

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Treatment of palm oil mill effluent using 2 stage reactors combined anaerobic hybrid reactor and anaerobic attached growth reactor (혼합공정과 부착성장공정을 조합한 2단계 혐기 조합공정에서 palm oil mill effluent의 처리)

  • Shin, Chang-Ha;Son, Sung-Min;Jeong, Joo-Young;Park, Joo-Yang
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.1
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    • pp.21-29
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    • 2013
  • Present study was conducted to evaluate the performance of Anaerobic Hybrid Reactor (AHR) combined with two types of anaerobic attached growth reactors at mesophilic temperature ($37^{\circ}C$). The reactor was operated at the influent substrate condition of 19,400 mg/L soluble chemical oxygen demand (sCOD). The organic loading rate (OLR) and flow rate were varied in the range of $9.5{\sim}22.5kg/m^3$. day and 10.6 ~ 26.0 L/day respectively since start-up was done. The COD removal efficiency of 93 % was measured at the OLR of $14kg/m^3$. day in AHR. However a reduction in removal efficiency to as low as 85 % could have been related to a combined effect of high concentration suspended solids (SS) concentration over 3,800 mg/L. On the other hand the total COD removal efficiencies were measured to be 96.3 % and 96.2 % for AHR+APF and AHR+ADF respectively. The pH of the POME was adjusted to neutral range by using sodium bicarbonate at the initial stages of the reactor feed, later stages pH adjustment was not required as the pH was maintained in the desired neutral range due to self-buffering capacity of the reactor. The reactor proved to be economically acceptable and operationally stable. The biogas was measured to have $CH_4$ and $CO_2$ with a ratio of 35:65, and methane gas production rate was estimated to be $0.17{\sim}10.269L\;CH_4/g\;COD_{removed}$.

1-D Model to Estimate Injection Rate for Diesel Injector using AMESim (디젤 인젝터 분사율 예측을 위한 AMESim 기반 1-D 모델 구축)

  • Lee, Jinwoo;Kim, Jaeheun;Kim, Kihyun;Moon, Seoksu;Kang, Jinsuk;Han, Sangwook
    • Journal of ILASS-Korea
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    • v.25 no.1
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    • pp.8-14
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    • 2020
  • Recently, 1-D model-based engine development using virtual engine system is getting more attention than experimental-based engine development due to the advantages in time and cost. Injection rate profile is the one of the main parameters that determine the start and end of combustion. Therefore, it is essential to set up a sophisticated model to accurately predict the injection rate as starting point of virtual engine system. In this research, procedure of 1-D model setup based on AMESim is introduced to predict the dynamic behavior and injection rate of diesel injector. As a first step, detailed 3D cross-sectional drawing of the injector was achieved, which can be done with help of precision measurement system. Then an approximate AMESim model was provided based on the 3D drawing, which is composed of three part such as solenoid part, control chamber part and needle and nozzle orifice part. However, validation results in terms of total injection quantity showed some errors over the acceptable level. Therefore, experimental work including needle movement visualization, solenoid part analysis and flow characteristics of injector part was performed together to provide more accuracy of 1-D model. Finally, 1-D model with the accuracy of less than 10% of error compared with experimental result in terms of injection quantity and injection rate shape under normal temperature and single injection condition was established. Further work considering fuel temperature and multiple injection will be performed.

우리나라 S/W 벤처기업의 경영현황

  • 한계섭;손성호
    • Proceedings of the Korea Association of Information Systems Conference
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    • 2000.11a
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    • pp.26-31
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    • 2000
  • It is said that the focus of managing venture business is currently moving from technology competition to management competition. By the way, the software venture business(SVB) has some weak points in its structural composition and itematization and no professional personnel in other several sections except technology development section. In addition, such basic functions as technology and R & D, finance and accounting, marketing required to the management of business are concentrated on only one man, its representative director. Therefore, this study aims to provide the basic data useful to the establishment of governmental policy in information and communication, to the rearing of the SVB by a local government related to the software, and to the administration of SVB by investigating the actual conditions. This study attempts to examine the literature on venture business and software industry, and its management with a questionnaire about the actual conditions of managing the SVB. The questionnaire is given to 527 local enterprises belonging to the Software Industry Association and to 171 enterprises in the Software Center. This study compromises the characteristics of the SVB, the actual conditions of its technology and R & D, finance and accounting, and marketing. The characteristics of the SVB are classified into categories such as the stage of its growth(the stage of its seed and start-up, the stage of tis development and growth, the stage of its stability and maturity) and the main business(the system integration, the software development for contract, the package software development service, the software-related service). Additionally, the study attempts to analyze positively the actual condition of its management after classified by the areas of business profile, its general management, its technology development, its finance and accounting, and its marketing The result of this study is found that the SVB has a lot of troubles in part of marketing and finance & accounting activity as well as general management. The SVB realizes the importance of the technology development rather than that of management activity including marketing activity. So we expect this study can assist the SVB to establish the business guidelines for own management plans.

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The Construction Status of Fuel Test Loop Facility (핵연료 노내조사시험설비의 시공 현황)

  • Park, Kook-Nam;Lee, Chung-Young;Kim, Hark-Rho;Yoo, Hyun-Jae;Yoo, Seong-Yeon
    • Proceedings of the SAREK Conference
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    • 2007.11a
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    • pp.305-309
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    • 2007
  • FTL(Fuel Test Loop) is a facility that confirms performance of nuclear fuel at a similar irradiation condition with that of nuclear power plant. FTL construction work began on August, 2006 and ended on March, 2007. During Construction, ensuring the worker's safety was the top priority and installation of the FTL without hampering the integrity of the HANARO was the next one. The installation works were done successfully overcoming the difficulties such as on the limited space, on the radiation hazard inside the reactor pool, and finally on the shortening of the shut down period of the HANARO. The Commissioning of the FTL is to check the function and the performance of the equipment and the overall system as well. The FTL shall start operation with high burn up test fuels in early 2008 if the commissioning and licensing progress on schedule.

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Commissioning Results of the Warm Compression System for the KSTAR Helium Refrigeration System (KSTAR 헬륨냉동기의 압축시스템 시운전 결과)

  • Park, Dong-Seong;Chang, Hyun-Sik;Joo, Jae-Joon;Moon, Kyung-Mo;Cho, Kwang-Woon;Kim, Yang-Soo;Bak, Ju-Shik;Kwon, Il-Keun;Cho, Myeon-Chul;Yang, Seung-Han
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.125-130
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    • 2008
  • The main components of the KSTAR helium refrigeration system (HRS) can be classified into the warm compression system (WCS) and the cryogenic devices according to the operating temperature levels. The WCS itself consists of the compressor station (C/S) and the oil removal system (ORS). The process helium is compressed from 1 bar to 22 bar maximum in the C/S and downstream, the ORS removes the oil mixed in the helium to less than 10 ppbw as per the operation criteria of the cryogenic devices of the KSTAR HRS. After the installation, the pre-commissioning and commissioning activities were started on July, 2007. Before the start-up of the C/S, vibration measurement and the skid reinforcement jobs were performed for stable operation of the C/S. The results of the WCS performance tests met the requirements of the KSTAR HRS but satisfied the vibration level criteria only at the compressors' full load condition.

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Safety-Related Bus Voltage Variation during Large Induction Motor Start-up in 1400MW Light Water Reactor Type Nuclear Power Plant (1400MW급 경수로형 원자력발전소의 대용량 유도전동기 시동시 안전관련 모선 전압 변동)

  • Lee, Cheoung Joon;Kim, Chang Kook;Noh, Young Seok;Joo, Young Hwan
    • Plant Journal
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    • v.12 no.4
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    • pp.37-43
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    • 2016
  • Power system which provides electricity to the accident mitigation load for nuclear power plant should be verified to maintain the proper voltage level under the various loading and source conditions. For this purpose, it was needed to collect the voltage data of safety related buses during operation of the Reactor Coolant Pump(RCP) motor and Component Cooling Water Pump(CCWP) motor, respectively, under the certain loading condition of the plant. The data (such as, voltage, current, power factor) collected from actual measurement were used to modify the existing ETAP model and then the reanalysis was conducted to simulate the testing conditions. Through these actual measurement and analysis, it ensures that the existing electrical system analysis including assumptions and methods was conducted properly. Finally, the voltage of safety related buses was not dropped below the acceptable level, and the discrepancy between two results was within the limit.

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A DYNAMIC SIMULATION OF THE SULFURIC ACID DECOMPOSITION PROCESS IN A SULFUR-IODINE NUCLEAR HYDROGEN PRODUCTION PLANT

  • Shin, Young-Joon;Chang, Ji-Woon;Kim, Ji-Hwan;Park, Byung-Heung;Lee, Ki-Young;Lee, Won-Jae;Chang, Jong-Hwa
    • Nuclear Engineering and Technology
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    • v.41 no.6
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    • pp.831-840
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    • 2009
  • In order to evaluate the start-up behavior and to identify, through abnormal operation occurrences, the transient behaviors of the Sulfur Iodine(SI) process, which is a nuclear hydrogen process that is coupled to a Very High Temperature Gas Cooled Reactor (VHTR) through an Intermediate Heat Exchanger (IHX), a dynamic simulation of the process is necessary. Perturbation of the flow rate or temperature in the inlet streams may result in various transient states. An understanding of the dynamic behavior due to these factors is able to support the conceptual design of the secondary helium loop system associated with a hydrogen production plant. Based on the mass and energy balance sheets of an electrodialysis-embedded SI process equivalent to a 200 $MW_{th}$ VHTR and a considerable thermal pathway between the SI process and the VHTR system, a dynamic simulation of the SI process was carried out for a sulfuric acid decomposition process (Second Section) that is composed of a sulfuric acid vaporizer, a sulfuric acid decomposer, and a sulfur trioxide decomposer. The dynamic behaviors of these integrated reactors according to several anticipated scenarios are evaluated and the dominant and mild factors are observed. As for the results of the simulation, all the reactors in the sulfuric acid decomposition process approach a steady state at the same time. Temperature control of the inlet helium is strictly required rather than the flow rate control of the inlet helium to keep the steady state condition in the Second Section. On the other hand, it was revealed that the changes of the inlet helium operation conditions make a great impact on the performances of $SO_3$ and $H_2SO_4$ decomposers, but no effect on the performance of the $H_2SO_4$ vaporizer.

A Low-Voltage Self-Startup DC-DC Converter for Thermoelectric Energy Harvesting (열에너지 수확을 위한 저전압 자율시동 DC-DC 변환기)

  • Jeong, Hyun-Jin;Kim, Dong-Hoon;Kim, Hoe-Yeon;Yoon, Eun-Jung;Yu, Chong-Gun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.520-523
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    • 2016
  • This paper describes a DC-DC converter with MPPT control for thermoelectric energy harvesting. The designed circuit converts low voltage harvested from a thermoelectric generator into higher voltage for powering a load. A start-up circuit supplies VDD to a controller, and the controller turns on and off a NMOS switch of a main-boost converter. The converter supplies the boosted voltage to the load through the switch operation. Bulk-driven comparators can do the comparison under low voltage condition and are used for voltage regulation. Also, bulk-driven comparators raise system's efficiency. A peak conversion efficiency of 76% is achieved. The proposed circuit is designed in a 0.35um CMOS technology and its functionality has been verified through simulations. The designed chip occupies $933um{\times}769um$.

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