• 한국압력기기공학회 논문집
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• 제8권3호
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• pp.23-27
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• 2012

A seawater pumps in the nuclear power plant is responsible for providing cooling water to other components all the time. Because of the depreciation, the seawater pump with current impeller consumes too much power for maintaining the total head. Therefore the objective of this study is to reduce power with maintaining certain the total head by cutting the current impeller. By using a commercial CFD code, FLUENT, the overall performance of seawater pump with current and modified impeller was simulated. Also Affinity law was applied at pumps with various impeller diameter and evaluated the validity of the affinity law. The numerical results show that the pump efficiency is quite irrelevant to the diameters of the impellers and the pump efficiency becomes worse over the designed flow rate. And affinity law result and numerical one show good agreements at small change of impeller diameter. One of the impeller diameters was decided to modify and was applied to the nuclear power plant with the numerical study above.

• The Journal of Asian Finance, Economics and Business
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• 제9권1호
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• pp.189-201
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• 2022

The study empirically examines the impact of monetary fundamentals along with global oil prices on the Pak-rupee exchange rate using the monthly data over 2001-2020. Employing the cointegrating vector autoregressive with exogenous variables (VARX) and vector error correction model with exogenous variables (VECMX), the study analyzes the impact of domestic monetary fundamentals while considering the foreign variables as weakly exogenous. In order to account for the structural breaks in the data, the Lagrange multiplier (LM) unit root test with two structural breaks has been used (Lee & Strazicich, 2003). The empirical results reveal that the domestic and foreign monetary variables significantly explain the exchange rate movements in Pakistan both in the long run and in the short run. The dynamic properties of the monetary model of exchange rate have been analyzed using the persistence profile analysis and generalized impulse response functions (GIRFs). The results reveal that the responses of shocks to domestic monetary fundamentals are consistent with the predictions of the monetary model of the exchange rate. Furthermore, being a net oil importer, a rise in global oil prices significantly depreciated the Pak-rupee exchange rate over the period of study. The global financial crisis (GFC) and pandemic (COVID-19) were also found to cause the Pak-rupee exchange rate depreciation.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.736-737
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• 2015

In these days, international construction market including construction companies has much grown due to globalization and economic boom in the mid 2000's. The size of international construction market, measured with overseas revenue of 225 construction firms, has expanded 2.7 times from 2003 to 2008 according to the ENR. However, after the global financial crisis of 2008 it has faced condition of low growth. In this research, major changes of international construction market and top contractors have been studied. In this study, changes of international construction market have been analyzed in the aspect of region and product including general buildings, transportation, petroleum, etc. Then, in order to find the changes of top contractors which obtained good accomplishment, business performance of companies have been examined by the compound annual growth rate, profit margin and international revenue by comparing the data before 2008 and after. The purpose of the study is to understand major changes of international construction market. Also, strategy changes of top contractors against market stagnation, profit depreciation, high competition have been inferred through the study. The result of the study would contribute to analyzing the strategies of construction companies in international market.

• 무역학회지
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• 제47권2호
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• pp.69-88
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• 2022

This paper aims to predict Busan's regional product and employment using the logistic regression models and machine learning models. The following are the main findings of the empirical analysis. First, the OLS regression model shows that the main industries such as electricity and electronics, machine and transport, and finance and insurance affect the Busan's income positively. Second, the binomial logistic regression models show that the Busan's strategic industries such as the future transport machinery, life-care, and smart marine industries contribute on the Busan's income in large order. Third, the multinomial logistic regression models show that the Korea's main industries such as the precise machinery, transport equipment, and machinery influence the Busan's economy positively. And Korea's exports and the depreciation can affect Busan's economy more positively at the higher employment level. Fourth, the voting ensemble model show the higher predictive power than artificial neural network model and support vector machine models. Furthermore, the gradient boosting model and the random forest show the higher predictive power than the voting model in large order.

• 대한교통학회지
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• 제25권6호
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• pp.89-97
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• 2007

고도의 산업화와 경제발전으로 인한 자동차 의존적인 교통체계는 도심의 교통혼잡, 에너지소비, 대기오염과 소음, 교통사고 등과 같은 많은 문제를 유발하고 있는 실정이다. 특히, 도심에서 자동차로 인한 대기오염은 과거 산업활동에 의해 발생된 공해문제보다 더욱 심각한 수준에 이르고 있다. 이에 본 연구에서는 미시적 시뮬레이션을 이용하여 자동차 배출가스 저감 효과를 파악하고 경제성 분석을 통해 도심지에서 대기오염을 최소화 하면서 차량 소통을 원활히 할 수 있는 교통정책이 무엇인지를 파악하였다. 그 결과, 차량 요일제가 투자비용이 없어 가장 효과적인 방법인 것으로 나타났으나 시민들에게 강제성을 부여함으로써 자동차 수요를 억제시키기 때문에 시민들과의 공감대 형성이 무엇보다 중요하며, 다른 대안들과 병행하여 추진하는 것이 효과적일 것이라는 결론을 얻었다. 향후 연구과제는 선호의식 조사를 통해 시민들이 생각하는 자동차 배출가스의 대기오염 영향을 조사하고 본 연구 결과를 통해 나타난 차량 요일제 도입시 참여 의사를 조사하여 실제 교통정책 도입 가능성 등을 파악하는 연구를 진행 해야겠다.

• Journal of Nutrition and Health
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• 제36권5호
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• pp.528-535
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• 2003

The purposes of this study were: 1) to investigate the operational and financial characteristics of contract-managed high school food services in Seoul, 2) to analyze the financial performance of high school food services 3) to develop guidelines for meal pricing and facilities investment costs. From Oct to Nov 2001, questionnaires were mailed to 249 high schools that were managed by contract food service companies. A 40.2％ response rate was recorded. The results of this study were as follows: 1. Student enrollment in high schools run by contract-managed food services was 1,518, with a 68.5％ participation rate in the school lunch program. The average meal price was 2,141 won. 2. Based on the income statement analysis, average total sales were 410,440,504 won and average net profit was 16,098,558 won. 3. The optimum food cost per meal was 1,200-1,300 won per meal, calculating using the methods of conversion factor, RDA (Recommended Daily Allowance), and nutrient exchange unit. 4. Guidelines for meal pricing were developed using the modified actual pricing method based on facilities investment cost, number of meals and food cost. The ratio of labor cost, general management expenses and ordinary profit were adopted from the schools with liability. The food cost, depreciation and interest cost were calculated based on unit meal. 5. The guideline for facilities investment was developed based on the number of meals, meal price and food cost. The guideline included the maximum facilities investment cost paid by the contract food service management company. (Korean J Nutrition 36(5): 528∼535, 2003)

• 한국식품과학회지
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• 제37권3호
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• pp.377-388
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• 2005

누에가루는 단백질과 섬유질 함량이 높았고, pH는 누에가루가 8.31로 밀가루의 5.80보다 상당히 높았으며 누에가루에서 pretense가 많이 존재하는 것으로 나타났다. Amylograph에서 누에가루 증가시 최고점도는 높아지는 경향이었다. 이는 누에가루에 존재하는 ${\alpha}$-glycosidase 활성을 억제하는 물질에 의해서 밀가루의 ${\alpha}$-amylas 활성이 억제되어 최고점도가 높아진 것으로 생각되었다. 누에가루 첨가시 반죽의 신장도와 저항도의 급격한 감소로 반죽의 글루텐 구조가 매우 약화되어 제빵성이 크게 저하되는 것으로 나타났으며 이는 누에가루에 있는 protease의 지나친 활성으로 확인되었다. 열처리한 누에가루의 casein 분해능이 16.93 IU인데 비해, 열처리하지 않은 누에가루의 pretense 활성도는 23.87 IU였다. 따라서 열처리를 통하여 누에가루의 pretense를 불활성시켜 사용함으로서 반죽의 물성이 개선되고 빵의 부피 증가 및 품질을 크게 향상시킬 수 있는 새로운 방법을 규명하였다. 그러고 ascorbic acid, SSL 및 gluten을 첨가하여 품질 향상을 더욱 보완하였고, 발효 저해는 lactic acid를 첨가함으로서 반죽의 pH를 조절하여 발효력을 향상시켰다. 열처리로 protease를 불활성화 시킨 누에가루를 사용하여 제조한 빵의 관능검사 결과 대조구와 같은 수준의 선호도를 보였으며 누에가루의 적정 첨가량은 2%수준으로 나타났다.

• 산업경영시스템학회지
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• 제21권48호
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• pp.133-144
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• 1998

International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. But, long-term & short-term interest rate is affected by Hanbo & Kia's bankruptcy, continuous large scale corporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge fund were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea. But if external factors from depreciation of yen and China's renminbi are instable, interest rate is expected to increase from capital's outflows. Third, if it is to decrease instability of foreign exchange rate from increase in surplus of future current account, credit rating's upwardness, stability of yen and renminbi, foreign exchange rate is expected to be stable. It is expected to have continuous stability from short-term interest rate to long-term interest rate in this empirical test.

• 농촌계획
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• 제21권1호
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• pp.143-154
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• 2015

This study has set up a plan to establish a trail as a means of maximizing a community by using the residents' living materials and unused facilities that a village holds now. A local archive is a place where the records and living materials collected from a village are preserved, displayed and shared with others, serving as a complex space with multiple functions. To apply the idea of 'utilizing a local archive', the empirical study was conducted by making an analysis of trail resources of Baekryeong Island and local archive application resources. Local archive resources were selected through evaluation of connection of trail routes by investigating and discovering the unused facilities of Baekryeong Island village and the depreciation level and scale of them. And actual local archive living references were investigated and collected through in-depth interviews of villagers. Also, through planning of trails by region, limitations of investigation activities were improved and various tangible and intangible resources owned by Baekryeong Island were utilized to enable effective and distinctive investigation activities and experiences. Unused facilities were surveyed and chosen to take advantage of the local archive space, along with in-depth interviews with the residents living in Baekryeong Island. In addition, the current conditions for the trail routes were checked out in order to 'point out the final routes'.

• 한국토양비료학회지
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• 제30권3호
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• pp.209-225
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• 1997

수십 년의 강우 및 증발 자료를 일목 요연하게 파악할 수 있도록 도표화하고 50mm 저장 증발 팬 모델을 적용하여 수원 지방 한발을 무성장 시간을 및 물 부족율로 계산하고 일별, 월별, 한발 발생 기간별 및 확률별로 계산하는 S/W를 제작 분석하였다. 증발산은 매년 유사한 주기성을 보이나 강우량과 분포는 년차별 차이가 커서 강우 분포가 한발의 주요 외적 원인이었다. 가장 심한 한발은 '64년 12월부터 65년 6월까지 190일간 이었고 가장 강우가 자주 있었든 시기는 '89년 6월부터 90년 9월까지 15개월이었다. 무성장 시간율을 기초로 감가 상각 년한이 10년 일 때 관개 투자 가능 금액을 계산한 결과 년간 총 조수익보다 적은 정도 이하이면 무난하다. 이 연구에서 제작된 S/W 는 각종 한발 지수의 도표화에 적합하여 타지역 한발 평가에도 유익할 것이다.