• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1995.10b
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• pp.110-117
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• 1995

본 연구는 퍼지모델링을 이용한 고속 소형선의 전체 저항곡선 및 마력곡선을 고속 소형선의 선형요소 자료들로부터 퍼지모델링 알고리즘을 통해 도출하고, 그 결과를 모형시 험 결과와 비교하고 있다. 또한 퍼지모델링 알고리즘에 의한 전체 저항곡선 및 마력곡선이 고속 소형선의 선형요소 결정에 효율적으로 적용됨을 보이고 있다.

• Analytical Science and Technology
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• v.12 no.5
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• pp.370-374
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• 1999

Extraction chromatography was used to scarch optimum separation conditions of terbium. Stationary phase was 2-ethylhexyl-2-ethylhexyl phosphonic acid(HEH[EHP])levextrel (-100~+150 mesh), column size was ${\Phi}20{\times}530mm$ and kept constantly temperature at $50^{\circ}C$, adsorption flow rate of $0.2mL/cm^2{\cdot}min$, elution flow rate of $1.0mL/cm^2{\cdot}min$, column diameter to packing height of 1:15. But to search optimum separation conditions of terbium, it changed the eluent acidity, the loading weight of sample. the composition of sample. In conclusion, acidity was 0.6 N HCl, loading weight of sample was about 5% and composition of sample was $Gd_2O_3(20%)+Tb_4O_7(60%)+Dy_2O_3(20%)$. Moreover purity of separated terbium by ICP-AES analysis was 99.98% in yield of 99.99%.

• International Commerce and Information Review
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• v.13 no.3
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• pp.511-541
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• 2011

The study analyzes the optimum Korea-China FTA negotiations by utilizing the Putnam's two- level game theoretic approach. According to the Putnam's theory, the size of the win-set depends on the strategies of the Level 1 negotiators. The size of the win-set depends also on the level 2 political institutions and the distribution of power, preferences, and possible conditions among Level 2 constituents. The basic principles for the successful future Korea-China FTA negotiations should be based on comprehensiveness, substantial liberalization and gradual liberalization with consideration of sensitive sectors. This study concludes that mid-level FTA strategy with comprehensive but low tariff reduction would be of best strategy for Korea. This study also suggests the utilization of the EHP(Early Harvest Program) for the successful Korea-China FTA negotiations.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.6
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• pp.470-475
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• 2007

The present study has been conducted economic analysis through actual operation of electric heat pump (EHP) and gas engine driven heat pump (GHP) which are installed at the same building in the university. Cost items, such as initial cost, annual energy cost and maintenance cost of each system are considered to analyze life cycle cost (LCC) and economical efficiencies are compared. The initial cost is considered on the basis of actual cost, and annual energy cost is converted into the cost after measuring electricity and gas consumption a day LCC applied present value method is used to assess economical profit of both of them. Variables used to LCC analysis are electricity cost escalation rate, natural gas cost escalation rate, interest rate, and service lives when each of them are 4%, 2%, 8%, and 20 years. The result shows that EHP (148,257,306 won) is more profitable than GHP (161,239,296 won) by 8.05% (12,981,990 won).

• KIEAE Journal
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• v.17 no.4
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• pp.67-74
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• 2017

Purpose: As the recent climate environment changes so rapidly, environmental problems such as hot weather and fine dust have occurred, and interest in environmental policies and technology development is increasing in countries around the world. Similarly in the Architecture, researches to reduce greenhouse gas emissions and to reduce energy application are actively conducted. Looking at previous studies, it is analyzed that the electric VRF is more energy efficient than the gas engine VRF. However, energy costs have changed due to recent price hikes and discounts on gas charges due to high electricity consumption in summer. Method: In this study, the actual building of Gas Engine VRF system was modeled using SketchUp program, and EnergyPlus was used to simulate actual building. Also, Electric VRF system was simulated, and compared with Gas Engine VRF system. Result: The total secondary energy requirement of Electric VRF system was 19.6% less than that of the Gas Engine VRF system, But when analyzing with primary energy requirement, EHP used 15.8% more energy. CO2 emissions were also estimated to be 16.9% more EHP. Energy costs were 14.8% more in Electric VRF systems, because their electricity charges are 0.6 to 160% more expensive than gas charges.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.236-236
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• 2010

단일접합 $n^+-p/p^+$ (p-emitter) 및 $p^+-n/n^+$ (n-emitter) GaAs 태양전지 (Solar Cell)를 각각 제작하여, 그 소자특성을 비교 분석하였다. AM 1.5 (1 sun, $100\;mW/cm^2$) 표준광을 조사할 경우, p-emitter/n-emitter 소자의 개방회로전압 (Voc), 단락회로전류 (Jsc), 충전율 (FF), 효율 (Eff)은 각각 0.910/0.917 V, $15.9/16.1\;mA/cm^2$, 78.7/78.9, 11.4/12.1%로서, n-emitter 소자가 다소 크지만 거의 비슷한 값을 가지고 있었다. 태양전지의 집광 특성을 분석하기 위하여 조사광의 출력에 따른 태양전지의 소자 특성을 측정하였다. 조사광 강도가 높아짐에 따라 p-emitter 소자의 특성은 점진적으로 증가하는 반면, n-emitter는 1.3 sun에서 약 1.4 배의 최대 효율 (17%)을 나타내고 조사광이 더 증가함에 따라 급격히 감소하는 특성을 보여 주었다. (그림 참고) 본 연구에서 사용한 2종류 소자의 층구조는 서로 반대되는 대칭구조로서, 모두 가까이에 위치하고 있는 표면전극 (surface finger) 방향으로 소수전하 (minority carrier)가 이동하고 다수전하 (majority carrier)는 기판 (두께 $350\;{\mu}m$)을 통한 먼 거리의 후면전극 (back electrode)으로 표류 (drift)되도록 설계되어 있다. 이때, n-emitter에서는 이동도 (mobility)와 확산길이 (diffusion length)가 높은 전자가 후면전극으로 이동하기 때문에 적정밀도의 전자-정공 쌍 (EHP)이 여기될 경우에는 Jsc와 Eff가 극대화되지만, 조사광 강도 또는 EHP가 더 높아질 경우에는 직렬저항의 증가와 함께 전류-전압 (I-V)의 이상인자 (ideality factor)가 커짐으로서 FF와 효율이 급격히 감소한 결과로 분석된다. 현재 전산모사를 통한 자세한 분석을 진행하고 있으며, 본 결과는 효율 극대화를 위한 최적 층구조 및 도핑 밀도 설계에 활용할 수 있을 것으로 판단된다.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.2
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• pp.136-146
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• 2019

A solid oxide fuel cell (SOFC) based hybrid desiccant cooling system model is developed to study the effect of fuel utilization rate of the SOFC on the reduction of energy consumption and $CO_2$ emission. The SOFC-based hybrid desiccant cooling system consists of an SOFC system and a Hybrid desiccant cooling system (HDCS). The SOFC system includes a stack and balance of plant (BOP), and HDCS. The HDCS consists of desiccant rotor, indirect evaporative cooler, electric heat pump (EHP), and heat exchangers. In this study, using energy load data of a commercial office building and SOFC-based HDCS model, the amount of ton of oil equivalent (TOE) and ton of $CO_2$ ($tCO_2$) are calculated and compared with the TOE and $tCO_2$ generation of the EHP using grid electricity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.133-139
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• 2023

The advantage of biofloc technology (BFT) in aquaculture is in the prevention of pathogenic transmission. In this study, we performed an investigation on viral, bacterial, and microsporidian parasite infections targeting a total of 194 whiteleg shrimp Litopenaeus vannamei reared in seven BFT-farms on the west coast of Korea in 2021. Hepatopancreatic and cuticular epithelium and pereiopods tissues of shrimp were tested for the four pathogens, Enterocytozoon hepatopenaei (EHP), Vibrio parahaemolyticus causing Acute Hepatopancreatic necrosis disease (VP_AHPND), white spot syndrome virus (WSSV), and hepatopancreatic parvovirus (HPV). The microsporidian parasite EHP was detected in the hepatopancreatic tissue of BFT whiteleg shrimp in the Ganghwa region, whereas no other pathogenic bacteria or virus was detected on the shrimp in the seven BFT-farms. As a result of bacterial flora in the rearing water of BFT whiteleg shrimp using DNA microbiome technology, V. chemaguriensis and V. alfacsensis were contained at 0.05% and 0.01%, respectively, but no VP_AHPND was detected. These findings will serve as a basis for supporting safe BFT-aquaculture of whiteleg shrimp.

• 한국기계연구소 소보
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• s.17
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• pp.133-144
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• 1987

Since the towing tank was operated from early 1979, the test and analysis methods have been established and applied for the performance prediction of ships. Especially the analysis programs for the resistance test ('EHP') and self-propulsion test ('DHP') based on the 1978 ITTC performance prediction method was modified as a name of 'PPTT' in order to include the form factor calculation, two-dimensional analysis method, the prediction on multi-screw ship and the organization of data filing system. Recently the program 'PPTT' was improved to cover the procedure of data fairing, the analysis of propeller-open-water test results carried out at low and high Reynolds numbers, etc. This paper describes the newly improved analysis program 'PTI'.

• KIEAE Journal
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• v.11 no.4
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• pp.71-78
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• 2011

The goal of this study is to analyze the impact of load factors on building energy consumption by using EnergyPlus program. We selected a campus building and monitored energy consumption from January 2009 to November 2010. First, we simulated energy consumption basically with weather data, building heat gain and EHP performance data. And then we simulated energy consumption with three additional parameter(infiltration, OA control and schedule). Simulation results are verified by MBE and Cv(RMSE) proposed by M&V guideline 3.0. Simulated total energy consumption was 104.3% of measurements, 4.33% of MBE, and 13.62% of Cv(RMSE). Results show infiltration and schedule were revealed as the most dominant factor of heating energy consumption and of cooling energy consumption, respectively.