• 한국산림과학회지
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• 제101권3호
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• pp.344-355
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• 2012

임목수확작업시스템 구축과 효율적인 임목수확작업 기술을 보급하기 위해 타워야더 및 스윙야더 등에 의한 전목집재작업시스템과 굴삭기 그래플 등에 의한 단목집재작업시스템의 작업시간 및 공정을 분석하였다. 전체 조사작업시간을 기준으로 분석한 1 cycle당 작업시간은 전목집재작업시스템에서 체인톱에 의한 벌목 46.6초/cycle, 타워야더에 의한 집재 480.6초/cycle, 스윙야더에 의한 집재 287.4초/cycle, 체인톱에 의한 조재 155.14초/cycle로 나타났다. 또 한 단목집재작업시스템에서는 체인톱에 의한 벌목 및 조재 225.65초/cycle, 굴삭기 그래플에 의한 단목집재 4,972초/cycle, 지엽집재 3,143초/cycle로 나타났으며, 바퀴식 미니포워더에 의한 소운재 4,688초/cycle, 굴삭기 그래플 및 소형운재차에 의한 소운재 2,118초/cycle로 나타났다. 전목집재작업시스템의 작업공정에서 체인톱에 의한 평균 벌목공정이 $57.89m^3$/일, 타워야더에 의한 평균 집재공정이 $20.3m^3$/일, 스윙야더에 의한 평균 집재공정이 $31.55m^3$/일, 체인톱에 의한 평균 조재공정이 $20.3m^3$/일로 나타났다. 또한, 단목집재작업시스템의 작업공정에서 체인톱에 의한 평균 벌목 및 조재공정이 $11.96m^3$/일, 굴삭기 그래플에 의한 평균 단목집재공정이 $34.75m^3$/일, 굴삭기 그래플에 의한 평균지엽수집공정이 $37.66m^3$/일, 굴삭기 그래플에 의한 평균 작업로의 개설공정이 73.8 m/일로 나타났으며, 바퀴식 미니포워더와 굴삭기 그래플 및 소형 운재차에 의한 평균 소운재 작업공정이 각각 $15.73m^3$/일과 $65.03m^3$/일로 나타났다.

• 한국건축시공학회지
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• 제9권6호
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• pp.151-159
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• 2009

최근 LNG 수요 증가로 인한 해외 LNG 플랜트 프로젝트의 지속적인 발주 증가로 국내 건설업체의 해외 진출이 크게 증가하고 있다. 또한 시공 및 사업관리 기술의 발전으로 예전에 비해 고부가가치를 창출할 수 있는 기회가 많아지고 있다. 그러나 일부 선도기업을 제외한 대부분의 중견 건설업체는 고급 인력과 실무 경험의 부족으로 인한 어려움을 겪고 있는 실정이다. 선진기업의 경우 체계화된 업무 프로세스 구축을 통해 이러한 어려움을 해결하였다. 이에 본 연구에서는 플랜트 사업의 생애주기 업무 프로세스 중 시공 전 단계를 대상으로 업무를 규명하고 지식관리 항목을 포함한 상세 프로세스를 분석하였다. 이는 전체 생애주기 업무 프로세스를 분석하고 표준화하는 연구의 사전 단계로 향후 지식관리 시스템을 개발하여 통합관리를 하는데 활용 할 수 있을 것으로 기대한다.

• Earthquakes and Structures
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• 제24권4호
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• pp.275-288
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• 2023

Based on the crucial role of high-speed railway bridges (HSRBs) in the safety of high-speed railway operations, it is an important approach to mitigate earthquake hazards by proceeding with seismic risk assessments in their whole life. Bridge seismic risk assessment, which usually evaluates the seismic performance of bridges from a probabilistic perspective, provides technical support for bridge risk management. The seismic performance of bridges is greatly affected by the degradation of material properties, therefore, material damage plays a nonnegligible role in the seismic risk assessment of the bridge. The effect of material damage is not considered in most current studies on seismic risk analysis of bridges, nevertheless. To fill the gap in this area, in this paper, a nonlinear dynamic time-history analysis has been carried out by establishing OpenSees finite element model, and a seismic vulnerability analysis is carried out based on the incremental dynamic analysis (IDA) method. On this basis, combined with the site risk analysis, the time-dependent seismic risk analysis of an offshore three-span HSRB in the whole life cycle has been conducted. The results showed that the seismic risk probabilities of both components and system of the bridge increase with the service time, and their seismic risk probabilities increase significantly in the last service period due to the degradation of the material strength, which demonstrates that the impact of durability damage should be considered when evaluating the seismic performance of bridges in the design and service period.

• Wind and Structures
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• 제37권4호
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• pp.289-302
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• 2023

Insulating glass units (IGUs) have been widely used in buildings in recent years due to their superior thermal insulation performance. However, because of the panel reciprocating motion and fatigue deterioration of sealants under long-term wind loads, many IGUs have the problem of early failure of watertight properties in real usage. This study aimed to propose a statistical method for wind-induced deflection of IGU panels during the whole life service period, for further precise analysis of the accumulated fatigue damage at the sealed part of the edge bond. By the estimation of the wind occurrence regularity based on wind pressure return period, the events of each wind speed interval during the whole life were obtained for the IGUs at 50m height in Beijing, which are in good agreement with the measured data. Also, the wind-induced deflection analysis method of IGUs based on the formula of airspace coefficient was proposed and verified as an improvement of the original stiffness distribution method with the average relative error compared to the test being about 3% or less. Combining the two methods above, the deformation of the outer and inner panes under wind loads during 30 years was precisely calculated, and the deflection and stress state at selected locations were obtained finally. The results show that the compression displacement at the secondary sealant under the maximum wind pressure is close to 0.3mm (strain 2.5%), and the IGUs are in tens of thousands of times the low amplitude tensile-compression cycle and several times to dozens of times the relatively high amplitude tensile-compression cycle environment. The approach proposed in this paper provides a basis for subsequent studies on the durability of IGUs and the wind-resistant behaviors of curtain wall structures.

• 한국공간구조학회논문집
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• 제6권3호
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• pp.51-57
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• 2006

본 연구의 목적은 한국건축프로젝트의 경영적 특성을 파악하는데 있다. 본문은 건축프로젝트의 주요 세 요소인 디자인, 건설, 유지관리의 프로세스 질 관리에 영향을 미치는 요소들을 조사한다. 설문조사는 건축관련 대학원생 및 교수, 설계자, 시공자들의 건축프로젝트에 있어서 프로세스 질 관리에 대한 상이한 시각을 보여주고 있다. 이러한 요소들을 분석함으로써 현재 국내의 질 관리 시스템과 프로그램 내용을 교정하고 개선하는데 도움이 될 것이다. 프로세스 질 관리에 있어서 여러 요소 중 설계자와의 협조가 가장 주요 요소로써 부각되었다.

• Parasites, Hosts and Diseases
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• 제55권2호
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• pp.193-196
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• 2017

This study investigated the development characteristics of Dermacentor everestianus under laboratory conditions. The time taken for D. everestianus to complete the whole life cycle was 110.2 days on average, and the average developmental durations of larvae and nymphs were 17.1 days and 29.5 days, respectively. The summation of the prefeeding, feeding, and preoviposition periods of females was 17.8 days, and the oviposition and egg incubation lasted for 18.1 days and 27.7 days, respectively. A highly positive correlation was observed between the weight of engorged female and the number of egg mass laid (r=0.947). The reproductive efficiency index and the reproductive fitness index were 7.1 and 6.1, respectively.

• 설비공학논문집
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• 제27권1호
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• pp.44-49
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• 2015

Ceiling cooling and heating system that consider load arrangement and space in the ceiling needs to be developed. Therefore, experimental and economic changes were done to verify the performance of compact type VAV. The test results were as follow. 1) Noise test result, measuring approximately 50.4 dB~56.6 dB (before ceiling in landfill), had a better ceiling deadline than the current measure, about a 10 dB noise reduction, so that the office baseline (40~50 dB) noise was judged to be less than test. 2) For the static pressure test result, taking out an outside hydrostatic 25 mmAq, 24.8 mmAq was measured, respectively, at the point. 3) For the life-cycle cost analysis result, the initial investment cost, maintenance replacement costs, and maintenance costs increased 0.2%, but the energy savings ratio was 19.5% while the whole life cycle savings of 40 years LCC was reduced 11.9%.

• 대한상한금궤의학회지
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• 제8권1호
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• pp.67-85
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• 2016

Objectives: In this paper, two cases which showed the meaningful results on the patients' chief complaints were analyzed. The patients were treated with the Mahwang-Haengin-Gamcho-seokgo-tang herbal medication based on Shanghanlun disease pattern identification diagnostic system. Methods: The patients were diagnosed based on Shanghanlun, disease pattern identification diagnostic system. In case 1, the change of menstruation cycle was noted and pre-menstrual discomforts were measured with Menstrual Distress Questionnaire(MDQ). In case 2, Quality of life questionnaire for adult Korean asthmatics (QLQAKA) was used to estimate the quality of the patient's life. Results: All the symptoms were improved after the Mahwang-Haengin-Gamcho-seokgotang treatment. In case 1, the menstruation cycle decreased to 30 days average. MDQ score decreased 143 to 103. In case 2, the change of the QLQAKA score as 1.647 average point is considered as a meaningful improvement. Conclusion: With great difference to a 'Symptom-Medicine' diagnostic system, the disease pattern identification diagnostic system seeks the pathologic pattern through the patient's whole life. More studies and multiple cases based on the diagnostic system are needed to prove this possibility later.

• 한국전자거래학회지
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• 제9권2호
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• pp.87-108
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• 2004

기존의 건설산업에서는 건설산업의 전 생명주기 동안 발생하는 모든 설계도면과 시방서 및 문서를 방대한 분량의 종이로 관리하여 왔다. 그 결과 유사 공사 실적자료의 재사용, 설계자와 시공자간의 정보교환ㆍ공유에 있어 공사의 실적저하, 예산낭비 등의 문제를 가져왔다. 이러한 문제를 해결하기 위하여 건축 정보의 교환ㆍ공유에 기존의 형식인 종이대신 전자화 된 도면과 문서를 사용하도록 하는 업무개선의 요구가 있어왔고, 이러한 문제를 총체적으로 해결하기 위하여 정부차원의 건설분야 전자거래프로그램이 요구되게 되었다. 본 논문은 건설CALS/EC(Continuous Acquisition and Life Cycle Support/Electronic Commerce)와 관련된 요소기술의 국내외적인 적용사례를 바탕으로 하여 도면전자납품을 위한 건설 CALS/EC에서 표준기술이 되는 요소기술의 활용방안과 향후 개발 방향에 관하여 제시해 보고자 한다.

• KIEAE Journal
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• 제12권1호
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• pp.105-112
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• 2012

When a building is planned and designed, the design should be able to minimize the cost during the whole life cycle of the building. This study has begun to analyze LCC about the alternative design which is applicable to renewable energy facility construction. It is reviewed domestic and foreign papers about the trend of LCC technology and it is determined the analytical method to analyze the LCC of renewable energy. Regarding the review of alternatives, it is chosen the three alternatives which are able to designed combing the renewable energy facilities and it is performed the LCC analysis about each alternative. Alternative 1 is Photovoltaic + Solar Thermal + Photovoltaic /Wind Power, Alternative 2 is Geothermal + Photovoltaic, and Alternative 3 is Photovoltaic + Solar Thermal. The LCC analysis is present value method, its analytical period is 40 years and it is applied 3.2% of real discount rate. As a result, it is proved that Alternative 1 and Alternative 3 are not able to collectible the early investment cost during the analytical period and Alternative 2 is analyzed that its pay-back period of early investment cost is about 31 years. As the final outcome of this study on case analysis, it is more advantageous to use the combination of Geothermal and Photovoltaic energy than to use the other combination in LCC aspect.