• 한국물환경학회지
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• 제29권2호
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• pp.259-269
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• 2013

This study aims to show the feasibility of wastewater reuse through hydrological analysis and propose a framework for planning using multi-criteria decision making technique. Ten alternatives of wastewater reuse (BOD: 3.0 mg/L & 4.7 mg/L) and two references in the urban watershed were considered and analyzed by using Hydrological Simulation Program in Fortran (HSPF). Though wastewater reuse has a positive effect on water quantity, it may degrade the water quality due to the high discharge concentration. This study showed that wastewater reuse can be a great alternative for the rehabilitation of distorted water cycle, if the quality is improved up to the natural streamflow and the quantity is increased up to the instreamflow requirement. In addition, to determine the project priority, three criteria were compared: 1) impacts on water quantity and water quality, respectively, 2) consideration of present hydrologic vulnerabilities on water quantity and quality and not, and 3) social and economic considerations and not. From the performance values to all criteria, the specific ranking can be derived and the feasibility of each wastewater reuse project can be checked with the comparison of the existing facilities. As a result, DJ and DR were derived to become effective in any evaluation conditions while SS and WG were improper alternatives if various criteria were considered. The decision making for project prioritization must be careful with the consideration of various impacts of wastewater reuse because the evaluation of wastewater reuse alternative showed very different priorities for each criteria.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.634-637
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• 2003

건설 자동화 장비 개발의 성공여부를 판단하고 이를 실용화하기 위해서는 개발 장비의 성능평가 및 분석을 통해 재래식 방식과 비교하여 자동화 방식을 도입함으로써 얻을 수 있는 기대효과가 제시되어야만 한다. 본 연구에서는 최근 국내에서 개발된 흄관매설 자동화 장비의 성능분석을 위한 평가모델 및 방법론을 제시하고 수차례의 현장실험(field trials)을 통해 수집된 실험 데이터를 바탕으로 재래식 흄관매설 방식과 자동화 방식의 성능을 종합적으로 비교${\cdot}$분석함으로써 재래식 방식에 비해 자동화 방식의 도입을 통해 얻을 수 있는 정성적${\cdot}$정량적 기대효과를 제시하였다. 흄관매설 자동화 장비의 성능분석을 위해 본 연구에서 ,제시된 성능분석 프로세스 및 평가모델은 향후 건설자동화 관련 기술개발 시 자동화 장비의 성능분석 및 평가모델을 개발함에 있어 기본적 틀(template)을 제공할 수 있을 것으로 기대된다.

• 한국건설관리학회논문집
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• 제5권1호
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• pp.157-167
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• 2004

건설 자동화 장비 개발의 성공여부를 판단하고 이를 실용화하기 위해서는 개발 장비의 성능평가 및 분석을 통해 재래식방식과 비교하여 자동화 방식을 도입함으로써 얻을 수 있는 기대효과에 대한 검증이 이루어져야 한다. 본 연구에서는 최근 국내에서 개발된 흄관매설 자동화 장비의 성능분석을 위한 평가모델 및 방법론을 구축하고 수차례의 현장실험(field trials)을 통해 수집된 실험 데이터를 바탕으로 재래식 흄관매설 방식과 자동화 방식의 성능을 종합적으로 비교$\cdot$분석함으로써 재래식 방식에 비해 자동화 방식의 도입을 통해 얻을 수 있는 정성적 $\cdot$정량적 기대효과를 제시하였다. 흄관매설 자동화 장비의 성능분석을 위해 본 연구에서 제시한 성능평가 모델 및 방법론은 향후 건설자동화 관련 기술개발 시 자동화 장비의 성능평가 및 분석 모델을 개발함에 있어 기본적 틀(framework)을 제공할 수 있을 것으로 기대된다.

• Ocean and Polar Research
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• 제38권3호
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• pp.225-234
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• 2016

This project sought to conduct an economic feasibility study regarding the commercial production of bio-hydrogen by the marine hyperthermophilic archaeon, Thermococcus onnurineus NA1 using carbon monoxide-containing industrial off-gas. We carried out the economic evaluation of the bio-hydrogen production process using the raw material of steel mill by-product gas. The process parameter was as follows: $H_2$ production rate was 5.6 L/L/h; the conversion of carbon monoxide was 60.7%. This project established an evaluation criterion for about 10,000 tonne/year. Inflation factors were considered as 3%. The operating costs were recalculated based on prices in 2014. The total investment required for development was covered 30% by capital and 70% by a loan. The operation cost for the 0.5-year test and integration, and the cost for the first three months in the 50% production period were considered as the working capital in the cost estimation. The costs required for the rental of office space, facilities, and other related costs from the construction through to full-scale production periods were considered as continuing expenses. Materials, energy, waste disposal and other charges were considered as the operating cost of the development system. Depreciation, tax, maintenance and repair, insurance, labor, interest rate charges, general and administrative costs, lubrication and miscellaneous expenses were also calculated. The hydrogen price was set at US$ 4.15/kg for the economic evaluation. As a result, the process was considered to be economical with the payback period of 6.3 years, NPV of 18 billion Won and IRR of 26.7%.

• 대한물리의학회지
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• 제14권1호
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• pp.151-161
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• 2019

PURPOSE: To investigate the validity of a smartphone application for post-stroke daily living activity management based on an evaluation by users and experts. METHODS: The study design adhered to the analysis, design, development, implementation, and evaluation ADDIE (Analysis-Design-Development-Implement-Evaluation) model. We downloaded the application onto the smartphones of 33 users and 30 experts, taught them how to use it, and asked them to use the application for four weeks. The users' daily lives before and after using the application were compared based on the K-MBI (Korean Version of Modified Barthel Index) to evaluate the usability of the application. For the expert group, we investigated the content validity and reliability of the application and evaluated the usability of the application. Data were analyzed using the SPSS 21.0 software. Users' general characteristics and experts' evaluation scores were analyzed using descriptive statistics. Content validity was tested using the content validity index (CVI), and reliability was tested with Cronbach's alpha. Users' K-MBI scores before and after using the application were compared with the paired sample t-test. RESULTS: Users gave an average rating of 2.93 out of 4 for the application for managing the daily lives of stroke patients, while experts gave an average score of 3.14. With regard to the K-MBI scores, only the dressing score improved significantly (p<.005) after using the application, and scores for other categories slightly improved but not to significant levels. CONCLUSION: The results of this study suggest that the STROKECARE application is usable and could help stroke patients manage their daily lives.

• 한국철도학회논문집
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• 제13권1호
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• pp.119-124
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• 2010

경량전철시스템은 대도시내 주요 거점을 연결하는 간선교통, 지하철 노선이 닿지 못하는 지역의 교통수요를 기존 지하철에 연결시키는 개념의 지선 및 순환교통, 그리고 공항, 위락지역 등 대단위 교통 밀집지역의 접근교통 등의 역할을 한다. LIM, 노면전차, 모노레일 도입시 시장성과 경제성분석을 통해 각 시스템의 도입 타당성을 제시하고 국내 환경에 적합한 시스템 개발 및 향후 국외 시장의 선점효과를 정량적으로 제시하고자 하였다. 이에 경량전철의 특징 및 국내외 도입현황을 분석하였으며, 경제적 타당성 분석을 위해 산업연관분석을 하여 매출 및 부가가치를 전망하고 최종적으로 비용-편익 분석을 수행한 결과 대상 시스템 모두 경제성이 있는 것으로 분석되었다. 이러한 비용편익비율은 향후 경량전출 도입은 효율성으로 의미하기 보다는 사업성의 유무 판단으로 사용하는 것이며, 모든 시스템에 있어 경제성이 있는 것으로 판단된 만큼, 노선별 특성에 맞는 시스템 도입을 위한 다양한 방식의 경량전철 개발이 필요함을 알 수 있다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권2호
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• pp.94-99
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• 2013

Purpose: The purpose of this study was to evaluate the feasibility of the outfracture osteotomy sinus graft technique with the evaluation of 8.5 year survival rate of the implants placed in the atrophic edentulous posterior maxillary area. Methods: One hundred and seventy-six cases of 145 patients who visited our center from August 2004 to February 2013 and were diagnosed as atrophic edentulous maxillary alveolar ridge, were selected and underwent sinus graft with outfracture osteotomy sinus graft technique. Feasibility of the outfracture osteotomy sinus graft technique was investigated with clinical and radiographic evaluation to assess the survival rate of the total dental implants in augmentation sinus surgery. Total fixture number available in follow-up period was 320, in which the lost 15 patients were excluded out of 160 patients. Results: Eight point five year cumulative survival rate was 95.6% with 14 failures of total 320 fixtures. The average follow-up period was 28 months 16 days with the minimum and maximum follow-up periods of 4 months 5 days and 94 months 10 days, respectively. Conclusion: Traditional infracture technique is a popular method for an augmentation sinus surgery. The authors modified this classical method by outfracturing and readapting the bony window after sinus graft, with excellent treatment results evidenced by high survival rate, which proves the feasibility of the newly-designed outfracture osteotomy sinus graft technique.

• 한국전산구조공학회논문집
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• 제23권4호
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• pp.425-434
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• 2010

본 연구에서는 고층건물 구조시스템의 다양한 대안으로부터 이들의 성능을 합리적으로 평가하는 방안을 제안하였다. 대안평가는 업무절차에 따라 예비평가, 본평가, 실시평가로 나누어 수행된다. 대안평가를 위한 평가범주는 구조성능, 경제성, 공기의 세 가지로 구성되고, 각 평가범주는 이들을 평가하기 위한 세부 평가항목으로 구성된다. 예비평가에서는 경험지식에 의한 정성적인 평가를 수행하며, 본평가와 실시평가에서는 수치적인 결과를 바탕으로 주로 정량적인 평가를 수행한다. 평가결과의 종합화는 평가항목들간의 관계가 선형적이라는 가정하에 가중평균법을 적용하였다. 제안된 대안평가 방안은 실무예제에 대한 시뮬레이션을 통하여 그 적용성을 검토하였다.

• Geomechanics and Engineering
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• 제19권3호
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• pp.283-293
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• 2019

Evaluating the stability of the excavation face of the cross-river shield tunnel with good accuracy is considered as a nonlinear and multivariable complex issue. Understanding the stability evaluation method of the shield tunnel excavation face is vital to operate and control the shield machine during shield tunneling. Considering the instability mechanism of the excavation face of the cross-river shield and the characteristics of this engineering, seven evaluation indexes of the stability of the excavation face were selected, i.e., the over-span ratio, buried depth of the tunnel, groundwater condition, soil permeability, internal friction angle, soil cohesion and advancing speed. The weight of each evaluation index was obtained by using the analytic hierarchy process and the entropy weight method. The evaluation model of the cross-river shield construction excavation face stability is established based on the idea point method. The feasibility of the evaluation model was verified by the engineering application in a cross-river shield tunnel project in China. Results obtained via the evaluation model are in good agreement with the actual construction situation. The proposed evaluation method is demonstrated as a promising and innovative method for the stability evaluation and safety construction of the cross-river shield tunnel engineerings.

• 농업과학연구
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• 제30권1호
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• pp.89-101
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• 2003

For the pre-feasibility study and project evaluation, the discount rate or cutoff rate should be given by the government authority. To get the Benefit/Cost Ratio, NPV(Net Present Value) and IRR(Internal Rate of Return) of the public investment projects, the pertinent and realistic discount rate should be determined to be suitable to the present time period. The cut-off rates in Korea were equivalent to 15% in 1970's, 10% in 1980's and 8% in 1990's. The prevailing rate of discount as 8% is considered not to be suitable for the 2000's public project appraisal considering the present interest rates on deposit and national bonds. To determine the socio-economic feasibility of the public projects, the IRR should be bigger than the present cutoff rate. When we still use the high old rate of discount, the analytical results of project appraisal will show always economically unfeasible. Therefore the new rate of discount suitable for present time should be determined by the government. The public projects to be implemented in 2000 year onward are recommended to be adapted 5% of cutoff rate for the project appraisal and evaluation according to the results of reviewing the tendency of discount rates and market rates of interest in Korea.