• 한국환경복원기술학회지
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• 제10권6호
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• pp.120-129
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• 2007

Rapid urbanization has transformed the spatial pattern of urban land use or cover. This paper concentrates that changed characteristics of landscape structure in the Tancheon Watershed, from 1995 to 2003 were investigated using land cover map. We used FRAGSTATS software to calculate landscape indices to characterize the landscape structure. We found that built up area has been increased rapidly during the study period, while cultivated area and forest area have been decreased rapidly in the same period. From 1995 to 2003, built up area was increased from 19.73% to 39.62% and cultivated area and forest area was decreased 17.60% to 5.97% and 58.31% to 49.41%. Number of patches, mean euclidean nearest-neighbor distance, contagion index, Shannon's diversity index increased considerably from 1995 to 2003, also suggesting the landscape in the study area became more fragmented and heterogeneous. but because of continuously fragmentation, landscape became homogeneity. The study demonstrates that landscape metrics can be a useful indicator in landscape monitoring and landscape assessment.

• Steel and Composite Structures
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• 제10권3호
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• pp.261-279
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• 2010

Generally, a box tube, which is used for an existing square CFT structure, is made by welding four plates. The manufacturing efficiency of this steel tube is poor, and it also needs special welding technology to weld its internal diaphragm and the through diaphragm. Therefore, an interior-anchor-type square steel tube was developed using the method of cold-forming thin plates to prevent welding of the stress concentration position, and to maximize the section efficiency. And, considering of the flow of beam flange load, the efficiency of erection and the weldability of the diaphragm to thin walled steel column, the external diaphragm connection was selected as the suitable type for the welded built-up square CFT column to beam connection. And, an analytical study and tests were conducted to evaluate the structural performance of the suggested connection details and to verify the suggested equations for the connection details. Through this study, the composite effect of the internal anchor to concrete, the resistance and stress distribution of the connections before and after the existing column is welded to the beam, the effective location of welding in connection were analyzed.

• 대한조선학회논문집
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• 제45권6호
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• pp.719-725
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• 2008

In this paper, noise and vibration reduction for floating-floored ship cabin is studied. A mock-up is built by using 6 mm steel plate, and two identical cabins are made for simulation of ship cabins. When a speaker is used as a sound and vibration sources, it is shown that floating floor is more effective in isolating sound than bare deck by 2-5 dB. It is also shown that structure-borne noise of the bare deck is greater than that of floating-floored deck by 3-10 dB. For tapping machine excitation, it is found that the effect of floating floor in airborne noise and structure-borne noise reduction reaches up to 40-50 dB for high frequency ranges.

• 보존과학연구
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• 통권13호
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• pp.9-13
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• 1992

An Woljung wooden bridge structure, which assumde to has been built in the unification of shilla dynasty, was excavated at Nam-chun river basin inKyung-ju. As a result of primary investigation, the weigh loss was 70-80% and the volumetric shrinkage was up to 38% without any conservation. Between 1986 and1991, they were conserved by the two step PEG treatment at the Mokpo Conservation Institute for Maritime Archaeological Finds.

• 한국인터넷방송통신학회논문지
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• 제14권6호
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• pp.199-205
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• 2014

효과적인 중소기업 정보화를 위하여 표준화된 생산정보화 시스템 개발 방법론(PSDM)을 통하여 단계별 주요 업무에 대한 작업을 정의하고 관련 연관도를 통하여 업무에 대한 선행 및 후행 관계를 정의한 후 그에 따른 프로젝트 범위 일정 비용 인적자원 관리를 위한 최적의 업무분류체계(WBS : Work Breakdown Structure)를 연구개발 하고자한다. 시스템의 신뢰성 품질 생산성 향상을 위한 관리 항목 설정, 중소기업 IT업체 감리업체 등 참여 기업간의 의사소통, 그리고 구축된 생산정보화의 유지보수를 포함한 운영지원 등 보다 체계적이고 효율적인 시스템 구축을 위해 중소기업 생산정보화에 적합한 WBS의 연구로 생산정보화를 구축하고자 참여하는 많은 중소기업 및 IT업체들이 표준화된 방법론을 이용하여 시스템 구축을 보다 효과적으로 수행할 수 있으며, 보다 높은 신뢰성을 가진 시스템을 계획된 개발 일정에 알맞게 구축한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집
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• pp.14-16
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• 2008

Built-in voltage in organic light-emitting diodes was studied using modulated photocurrent technique ambient conditions. From the bias voltage-dependent photocurrent, built-in voltage of the device is determined. The applied bias voltage when the magnitude of modulated photocurrent is zero corresponds to a built-in voltage. Built-in voltage in the device is generated due to a difference of work function of the anode and cathode. A device was made with a structure of anode/$Alq_3$/cathode to study a built-in voltage. ITO was used as an anode, and Al and LiAl were used as a cathode. A layer thickness of Al and LiAl were 100nm. Obtained built-in voltage is about 1.0V in the Al layer was used as a cathode. The obatined built-in voltage is about 1.6V in the LiAl layer was used as a cathode. The result of built-in voltage is dependent of cathode. We can see that the built-in voltage increase up to 0.4V when the LiAl layer was used as the cathode. These results correspond to the work function of LiAl which is lower than that of Al. As a result, the barrier height for an electron injection from the cathode to the organic layer could be lowered when the LiAl was used as a cathode.

• 건축역사연구
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• 제15권3호
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• pp.99-118
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• 2006

We have focused on the building appearance according to the change of conservation policy and urban fabric in Bukchon, Seoul. The Urban Hanok, urban traditional housing type, had been evolved in modern contort from 1920's to 1960's, that is to say, many buildings(Urban Hanok) in Bukchon area has built up with a lot and road at the same time. But the change of conservation policy has an effect on the urban fabric and building(wooden structure, RC and brick building). Thus many types of building in Bukchon has undergone a various change. The purpose of this paper is to define a change factor of Bukchon buildings. Thus we need to pay attention to policy and urban fabric. We reached the result as follows. First, the change of architecture regulations according to the several policies(an aesthetic area, an altitude area for sky line restriction and so on) brought into building deformation and eventually the historic scenery of Bukchon has been spoiled. Second, the change of policy had an effect on the change of roads and lots. Buildings on a widen road and a united lot was built newly. But new buildings built up with a concrete or brick structure was not in harmony with the historic scenery of Bukchon area. Third, a development method of a large lot with lack prudence(disregarded a scale and size of lot) did damage to Urban hanok and urban fabric. With the understanding on the relationship of buildings, a urban fabric and a policy in Bukchon, we can define the identity and correspond with the urgent request for a the conservation of historic urban scenery In addition we can suggest the policy and the design guidelines for the reservation and rehabilitation for Bukchon, Seoul.

• 동력기계공학회지
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• 제14권3호
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• pp.77-82
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• 2010

In general, the control valves are essential components in hydraulic systems. Structural changes within the valves remain a challenge because many parameters of valve tend to interact in terms of static and dynamic performance. Therefore, the valve characteristics is applied directly to the stability of hydraulic system. Inner structure of the valve which is used mainly in the industries is made up poppet type and spool type. This paper made a description of the method for numerical analysis and modeling of the valve with a built-in moving part of four-type. Based on the physical parameters of the valves, a numerical model of objected valve is developed using the bond graph method. It is to verified the results that the moving part of four-type has an effect on pressure and flow characteristics. Also, It is analyzed the results which has an effect on response characteristic by angular of poppet valve face and inertia variation of the valve with a built-in moving part. In the results, it is confirmed that the rising and settling time vary with the shape of moving part in valve.

• Journal of Information Technology Applications and Management
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• 제20권2호
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• pp.161-176
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• 2013

The outcomes of entrepreneurship studies have been tried to help the entrepreneurs in start-up stages, but the outcomes of the entrepreneurship research are not fully utilized to guide the activities of the entrepreneurs in start-up businesses. To utilize the outcomes of entrepreneurship research for helping entrepreneurs effectively, an entrepreneurship ontology, a systemized specification of the knowledge in the entrepreneurship research, has to be established, Based on the entrepreneurship ontology, the knowledge of entrepreneurial processes can be illustrated, and a diagnosis and coaching system for the entrepreneurs can be built effectively. To establish an entrepreneurship ontology, this study investigates the intellectual structure of entrepreneurship studies by analyzing the contents of top journals in entrepreneurship field, and identifies the relationship among the key concepts through bibliometric analyses based on entrepreneurship corpus, This study suggests a method of establishing entrepreneurship ontology and utilization of the ontology. Through utilization of the entrepreneurship ontology, it is expected to explain the entrepreneurial processes effectively and to improve the rate of business success.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.751-755
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• 2003

In this paper, floor impact noise reduction in a steel structure is studied. A mock-up is built by using 6t steel plate, and two identical cabins are made where 25t panel is used to construct wall and ceiling inside the steel structure. Various floating floor systems are tested for which normalized impact noise is measured according to ISO 140-7. In addition, floor SBN(Structure-borne Noise) and floor damping are measured to study the effect of floating floor. structure. It is shown that VL(Visco-elastic Layer) is more effective when hard plates are added above the VL.