• 한국자동차공학회논문집
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• 제22권2호
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• pp.91-99
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• 2014

The common-rail injectors are the most critical component of the CRDI diesel engines that dominantly affect engine performances through high pressure injection with exact control. Thus, from now on the advanced combustion technologies for common-rail diesel injection engine require high performance fuel injectors. Accordingly, the previous studies on the numerical and experimental analysis of the diesel injector have focused on a optimum geometry to induce proper injection rate. In this study, computational predictions of performance of the diesel injector have been performed to evaluate internal flow characteristics for various needle lift and the spray pattern at the nozzle exit. To our knowledge, three-dimensional computational fluid dynamics (CFD) model of the internal flow passage of an entire injector duct including injection and return routes has never been studied. In this study, major design parameters concerning internal routes in the injector are optimized by using a CFD analysis and Response Surface Method (RSM). The computational prediction of the internal flow characteristics of the common-rail diesel injector was carried out by using STAR-CCM+7.06 code. In this work, computations were carried out under the assumption that the internal flow passage is a steady-state condition at the maximum needle lift. The design parameters are optimized by using the L16 orthogonal array and polynomial regression, local-approximation characteristics of RSM. Meanwhile, the optimum values are confirmed to be valid in 95% confidence and 5% significance level through analysis of variance (ANOVA). In addition, optimal design and prototype design were confirmed by calculating the injection quantities, resulting in the improvement of the injection performance by more than 54%.

• 신재생에너지
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• 제16권4호
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• pp.65-75
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• 2020

The value of tangible assets depreciates over their useful life and this depreciation should be adequately reflected in any tax or financial reports. However, the method used to calculate depreciation can impact the financial performance of solar projects due to the time value of money. Korean tax law stipulates only one method for calculating the depreciation of solar photovoltaic facilities: the straight-line method. Conversely, USA's tax law accepts other depreciation methods as solar incentives, including the modified accelerated cost recovery system (MACRS) and Bonus depreciation method. This paper compares different depreciation methods in the financial analysis of a 10 MW solar system to determine their effect on the financial results. When depreciation was calculated utilizing the MACRS and Bonus depreciation method, the internal rate of return (IRR) was 10.9% and 16.4% higher, respectively, than when the Korean straight-line depreciation method was used. Additionally, the increased IRR resulting from the use of the two US methods resulted in a 20.5% and 27.4% higher net present value, respectively. This shows that changing the depreciation calculation method can redistribute the tax amount during the project period, thereby increasing the discounted cash flow of the solar project. In addition to increasing profitability, USA's depreciation methods alleviate the uncertainty of solar projects and provide more flexibility in project financing than the Korean method. These results strongly suggest that Korean tax law could greatly benefit from adopting USA's depreciation methods as an effective incentive scheme.

• 기술혁신연구
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• 제22권3호
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• pp.287-310
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• 2014

지식기반 경제시대를 맞이하여 국가 간 경쟁이 치열해지고 있는 가운데 R&D 연구결과물에 대한 기술이전 사업화 중요성이 강조되고 있다. 기술이전 사업화를 위해선 기술개발자와 사업화주체인 기업간 이전비용에 대한 협의가 선행되어야 한다. 이전비용의 협의과정에서 기술가치 평가기관의 결과물이 활용되고 있으나, 결과물에 대한 신뢰성 문제는 기술이전 시장의 활성화에 걸림돌이 되고 있다. 본 논문에서는 사업화주체가 확정되지 않은 이전대상 기술에 대한 기술가치평가 신뢰성 제고방법에 대해 논한다. 제안하는 방법은 개관적인 기술 및 시장자료 등을 활용하여 발생 가능한 사업화 환경 시나리오에 대한 기술가치평가 결과물들을 그래프 형태로 도식화하여 제공하는 것을 특징으로 한다. 기술개발자와 수요자는 도출된 가치평가 정보를 활용하여 기술이전 거래금액의 적정성을 판단할 수 있게 될 것이며, 이를 통해 기술이전 거래가 활성화 될 것으로 기대된다.

• Tuberculosis and Respiratory Diseases
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• 제46권2호
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• pp.251-259
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• 1999

연구배경: 기관지경검사로 인한 합병증의 빈도는 비교적 낮으나 생명을 위협하는 중요한 합병증의 약 50% 가 전처치 약제에 의한 것으로 보고되고 있다. 전처치의 효과와 필요성에 관한 연구들은 비교적 단편적이고 그 결과도 다양하다. 저자들은 수행상태가 양호하며 비교적 간단한 검사를 필요로 하는 외래환자에서 기관지경겹사시 전처치의 필요성 유무를 조사하고자 본 연구를 시행하였다. 방 법: 80명의 환자들을 4군으로 분류하여 I 군은 위약(생리식염수), II 군은 atropine 단독, III 군은 atropine과 midazolam, IV 군은 atropine과 meperidine을 시술 30분 전에 근육주사하였다. 국소마취는 4% lidocaine 5ml를 분무기를 통해 흡입시키고, 10% lidocaine 3-4회 분무하였으며 검사를 시행하는 동안에는 2 % lidocaine을 기도내로 투여하였다. 본 조사는 전향적 무작위 이중 맹검법으로 실시하였고, 검사후 검사자와 피검자에게 설문조사를 실시하였다. 결 과: 각 군의 평균연령, 성별, 흡연력, 폐기능검사 성적, 시술전 혈역학적 지수(분당 맥박수와 산소포화도) 등의 임상적 특징은 차이가 없었다. 시술중에 투여한 2% lidocaine의 용량과 검사에 소요된 시간, 시술 후 환자가 검사실에서 퇴실하기 까지의 시간, 검사직 후와 검사 후 2 분에 측정한 혈역학적 지수는 각 군간에 유의한 차이가 없었다. 검사자는 시술의 용이성, 기침의 정도, 분비물의 정도와 검사에 대한 전반적인 느낌에 대하여 4등급으로 답하였는데, 분비물의 정도는 atropine을 사용한 군과 사용하지 않은 군사이에 유의한 차이가 있었고 검사에 대한 전반적인 느낌은 midazolam을 사용한 III 군에서 더 좋지 않았다. 피검자가 느낀 검사자체의 힘든 정도와 재검사에 대한 의향은 각 군간에 유의한 차이가 없었다. 결 론: 이상의 결과로 수행상태가 양호하고 간단한 시술이 필요한 외래환자에서 기관지경검사시 전처치는 재고되어야 할 것으로 생각되나 향후 보다 효과적인 전처치 방법에 관한 연구가 필요할 것으로 생각된다.

• 한국간호교육학회지
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• 제8권1호
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• pp.95-107
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• 2002

The purpose of this study is to determine the clinical nurses' knowledge of DM and diabetes patient education aptitude so as to provide a basis for clinical nurse training with respect to diabetes patient education program. The data has been collected through the questionnaires of 42 items from the Knowledge on DM and each 16 item from the Importance on the elements of diabetes patient and the Recognition for clinical nurses, respectfully. 166 nurses from a general hospital who had participated in clinical nurse training in Sep. 28 and Oct. 4, 2001 were subject to respond the questionnaires. Analysis has been done by using statistical method such as percentage, average, standard deviation, t-test, ANOVA, Duncan test and Pearson correlation coefficients. The findings are as follows: 1. Clinical nurses' knowledge levels of diabetes 1) The average level of nurses' knowledge about diabetes is 29.37 (right answer- finding rate: 70%), which is intermediate. 2) Amongst the nurses classified by their knowledge levels about diabetes, the group with less than one year career and that with more than 5 year careers are found to have higher knowledge levels. The item with the highest right answer-finding rate was 'Please find the wrong out of the following examples about foot care'. Meanwhile, the item with highest incorrect answer-finding rate was 'what does blood sugar control aims for amongst gestational diabetes?'. 2. Clinical nurses' importance and perception levels of educational training about diabetes 1) There were no differences amongst nurses' importance level about diabetes. 2) Nurses usually had high scores(4.30) in terms of the items related to the importances about educational training. 3) There were quite high recognitions of general characteristics and symptoms about diabetes, amongst the nurse cohorts working more than one year and less than 5 years, and over 5 years, the group belonging to the internal department, that having the previous experiences of dealing with diabetes, and that having their diabetic relatives and other close people. Meanwhile, strangely, the group who identified themselves as 'not good at treating diabetes' had a high recognition level of educational training about diabetes. 3. Relationship between knowledge levels and importance & perception levels of diabetes 1) The higher knowledge about diabetes nurses had, the more importance they recognized. 2) It is found that there was no relationship between knowledge and perception of diabetes. 3) The more importance about diabetes nurses had, the higher perception they obtained. In conclusion, there is an urgent need for systematic educational programs about diabetes including technical aspects, in order to upgrade and improve nurses knowledge levels. In addition, re-educational training should be provided at regular intervals. Further, we believe the nurses with high knowledge about diabetes and interests in the provision of educations for patients can be far more confident, and in return, patients can have better self-management about diabetes obtained through educations. Based on the above-mentioned findings, we would like to make the suggestion: re-evaluation about nurses' knowledge and cognition levels should be carried out after job training programs about diabetes.

• 한국도서관정보학회지
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• 제45권4호
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• pp.409-428
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• 2014

본 연구에서 부산대표도서관 건립의 입지후보지로 선정된 4곳의 입지후보지에 대하여 각각 비용편익분석과 순현재가치, 내부수익률의 방법을 활용하여 경제적 타당성을 분석하였다. 편익을 분석하기 위해 조건부가치측정법(CVM)을 활용하였으며, 지불의사금액(WTP)을 도출하기 위해 사전조사와 본조사로 구성된 두 차례의 설문조사를 수행하였다. 사전조사를 통해 각 후보지별 최적제시금액을 설계하였으며, 이를 토대로 각 5가지 유형의 제시금액을 설정하고, 본조사를 통해 각 후보지에 대한 지불의사금액(WTP)을 도출하였다. 분석 결과, 4곳 모두 부산대표도서관 건립을 위한 경제적 타당성이 있는 것으로 나타났으며, 그 중 편익-비용 비율이 가장 높은 곳은 부산시민공원 후보지임을 확인하였다.

• 수산경영론집
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• 제29권1호
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• pp.121-137
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• 1998

This study was conducted to examine the economic evaluation of the newly developed fish meal analog (BAIFA-M) in Korean rockfish feed. A raw fish feed (MP) and two commercially formulated diets (EP) were employed to compare weight gain (WG), feed conversion ratio (FCR) and survival rate (SR) from the sea cage culture system. By using the economic model in the practical sea cage culture system, feed cost, production cost and gross profit per kg production, rate of profit to gross revenue (RPGR), and internal rate of return (IRR) were calculated based upon the results of the experiment and the information of the private aquaculture farm (Young Chang) in Tong young, Korean. IRR criteria is one of the popular economic feasibility analysis methods applicable far aquaculture industry. This is an economic evaluation method to compare the given interest rate or the discount rate with IRR which can be calculated by the difference between the present value of the benefit stream and of the cost stream. The benefits of using EP on WG, FCR, SR, and production cost will be emphasized in this study. Fish averaging 20$\pm$3.6g (Mean$\pm$SD) were randomly distributed in each small cage (6m$\times$6m) as groups of 2,000 fish. By using 3 large size cages (12m$\times$12m), 12 small cages were constructed, and only 9 small cages were employed for three replicates of each diet treatment. To compare with MP diet, two sinking EP diets were designed by our laboratory and produced by the local feed company who wanted to promote these EP diets for the mass cage culture of Korean rockfish in the future. Two EP diets contain white fish meal and/or BAIFA-M as the main animal protein sources : WFM diet, maximum 43% of white fish meal : BAIEA- M diet, 30% of white fish meal nab replaced by BAIFA- M from WFM diet. Results are summarized in Table 1. Fish fed MP diet showed significantly lower SR than does fish fed two EP diets(P<0.05). However, there Were no significant difference on FCR among fish fed three practical diets. Table 1. Average feed conversion ratio (FCR), accumulative average survival rate (SR) and economic evaluation data far three practical diets. As we expected, BAIFA-M diet is more economical than WFM diet as well as MP diet. Feed cost and production cost per kg production from BAIEA - M diet were lower than those from WFM and MP diets. Moreover, gross profit per Kg production, RPGR and IRR from BAIFA- M diet were higher than those from WFM and MP diets. This economic evaluation study clearly indicated that MP diet should be replaced by the commerical formulated EP diets as soon as possible in the near future because MP diet is not economical in the practical sea cage culture system.

• 농업과학연구
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• 제34권1호
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• pp.85-97
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• 2007

This study aimed at analyzing the economic effect of outdoor swimming pool investment using the reservoir's amenity resources. We focused on the identification of the amenity value of reservoir in the rural area and the economic evaluation for establishing This study aimed at analyzing the economic effect of outdoor swimming pool investment using the reservoir's amenity resources. We focused on the identification of the amenity value of reservoir in the rural area and the economic evaluation for establishing infrastructure such as swimming pool based on the reservoir's landscape value. To this end, we have conducted the case study on the outdoor swimming pool in connection with Go-Bok reservoir in Yeon-Gi county, Chungnam Province and estimated its income effect on the rural community by cost-benefit analysis method. The research results are as follows; 1) Outdoor swimming pool participants, with 11,581 visitors totaled to Yeon-gi county every year, was estimated to spend the worth of 58,446 thousand won paid for the agricultural product purchase and etc. 2) Internal rate return of the outdoor swimming pool project was estimated to 16.19%, which considered to be economically feasible comparing with 10% of current capital opportunity cost. Based on the results of this study, we suggest the following strategies for development of amenity value of swimming pool in connected with the reservoir; 1) Reservoir amenities should be well preserved even after construction of swimming pool lest losing amenity values while managing the facilities. 2) Measures to increase the marketing value of intangible reservoir's amenities through promotion should be established. 3) Effective program for more visitors with longer staying and more agricultural products sales should be designed.

• 수산경영론집
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• 제52권2호
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• pp.1-31
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• 2021

This study is to evaluate the prior economic feasibility of the off-shore fisheries stock enhancement project. The main findings of this study can be summarized as follows: first, offshore fisheries stock enhancement project shall be implemented by dividing them into 1st·2nd·3rd projects for efficient promotion. The 1st·2nd·3rd projects will be conducted in a total of 50 locations (the eastern sea, the western sea, the southern sea, and the jeju sea areas), and the project period per unit will be five years, which will cost 1 trillion won. Second, according to the results of the survey on public awareness, the most consumed marine species in Korea over the past year were analyzed in the order of mackerel, hairtail, squid, yellow corvina, blue crab, and cod. The dominant response to the reason for consuming marine products in Korea was healthy well-being food and safe food. In addition, 67.9% of them have hesitated to purchase offshore fish species over the past year due to high prices, indicating that they are burdened by high prices. On the other hand, 79% of the respondents said that the government's policy was insufficient, according to a survey on whether the government's coastal marine resource creation policy was sufficient. Third, as a result of preliminary economic analysis of offshore fisheries stock enhancement project, the benefit-cost ratio is 4.01, net present price is 1,283.7 billion won, and internal rate of return is 91.7% per year, which means that the economic analysis ensures the feasibility of the projects. The results of this study provide useful information on securing or organizing budgets for offshore fisheries stock enhancement project by securing economic feasibility as a national infrastructure project that increases fishery income and public benefits such as consumption of marine products.

• 자원환경지질
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• 제42권2호
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• pp.133-141
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• 2009

본 연구는 지질자원 연구개발 분야에서 경제적 효과 분석 연구가 활발히 수행되지 않은 분야인 지하수자원 분야의 연구개발 사업을 대상으로 경제적 효과를 분석하고자 한다. 제주도 청정 대용량 지하수 개발사업 중 2004년에서 2007년 기간에는 5년간 44.70억원(2006년 가치, 5.5% 할인율 적용)의 연구개발비용을 지출하여 제주도 지하수 부존량 산정, 대용량 지하수 개발 가능 지역 선정 및 개발 타당성 제시 등의 연구가 실시되었다. 본 사업의 편익요소로 대용량(2만톤/일 이상) 지하수 부존지역 깨소 설정으로 3,600만톤/년의 제주도 지하수 개발지역을 확보한 것으로 보았다. 이에 지하수개발시업의 편익에 연구개발 기여도(9.97%)를 적용, 연구개발투자에 대한 경제성 분석을 실시하였다. 기존의 경제이론 및 결과자료(가상가치평가, 생산기석도)와 시장자료(수입단가, 시설용량)를 기초로 한 지하수개발사업의 편익을 도출하고, 사업의 실행화 시점 및 할인율의 변동에 따른 영향을 제시하였다. 분석 결과 상수도 및 병입수 상업화로 연간 총 1,223만톤의 지하수 이용은 2,934억원의 가치로 나타났으며, 연구개발 투자효과는 2006년 순현재가치(NPV)로 30년간 총 136.59억원, 비용대편익비율(B/C ratio)은 4.06이며 내부수익율(IRR)은 22.74%로 나타났다. 사업화 시행 시점을 기존 10년 후에서 5년 후로 앞당기는 경우 추가적인 55.80억원의 편익이 산정되며, 사업의 할인율이 1% 상승하는 경우 역시 166.73억원 편익이 발생하여, 순편익 121.82억원, 비용편익비 3.71로 연구개발사업 타당성을 확보한다.