• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.312-317
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• 1998

Reliable maintenance scheduling of main equipments is a crucial problem in thermal power stations in order to skirt overall losses of power generation resulted from severe failures of the equipments. A reasonable method was proposed to determine the maintenance scheduling of whole pump system in thermal power stations in order to reduce the maintenance cost by keeping the present avail-ability of the pump system throughout the operation. The dimensional reduction method was used to solve problems encountered due to few data which involved many operational factors in failure rate of pumps. The problem of bandlimited nature of data with time was solved by extrapolating future failures from presently available actual data with an aid of Weibull distribution. The results of the analysis identified the most suitable maintenance intervals of each pump type accordingly and hence reduce the cost of unnecessary maintenance with an acceptable range in the overall system availability.

• International Journal of Fluid Machinery and Systems
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• v.9 no.4
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• pp.307-312
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• 2016

The present study reported of the use of special shaped blade to reduce the difference in pressure across the Wells turbine for wave energy conversion. The blade profile was composed of NACA0020 airfoils and trailing edge was notched like chevron. Experiments were performed investigating the influence of trailing edge shape on the turbine performance. Four notch depths were used to investigate the effect of depth of cut on the turbine performance. As results, by placing a notch-cut at the trailing edge of the blade, it was possible to reduce the pressure difference across the turbine without lowering the efficiency. In addition, the pressure difference substantially reduced at a constant rate with the increase of the cut ratio.

• International Journal of Contents
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• v.16 no.1
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• pp.1-9
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• 2020

Recently, the number of traffic accidents on trunk roads tends to decrease due to the performance improvement of passenger vehicles. In the commuter rush hour of morning and evening, vehicles via residential road increases without going along trunk roads. Therefore, there are many traffic accidents of pedestrians (or bicycles) and vehicles on residential roads. In order to safeguard residents against traffic accidents, traffic calming devices (TCD), such as chicane, speed hump, and school zone, etc. have been introduced. Investigating these effects repeatedly is not easy since many times and efforts are required, such as observed at the place actually. In this paper, the effects of TCDs in residential areas, such as noise, speed, and emission of a vehicle, using Simulation of Urban Mobility (SUMO) are examined. As a result, it is found that it is possible to reduce the speed of the vehicle by TCD, and the level of noise at the location behind TCD becomes higher than the level of noise at the location of TCD implemented.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.368-371
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• 2003

A new accurate and reliable human-in-the-loop control by artificial neural network (ANN) for human assistance robot was proposed in this paper. The principle of human-in-the-loop control by ANN was explained including the system architecture of human assistance robot control the design of the controller the control process as well as the switching of the different control patterns. Based on the proposed method, the control of meal assistance robot was implemented. In the controller of meal assistance robote a feedforward ANN controller was designed for the accurate position control. For safety a feedback ANN forcefree control was installed in the meal assistance robot. Both controllers have taken fully into account the influence of human arm upon the meal assistance robote and they can be switched smoothly based on the external force induced by the challenged person arm. By the experimental and simulation work of this method for an actual meal assistance robote the effectiveness of the proposed method was verified.

• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.70.6-71
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• 2008

• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.76.4-76.4
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• 2008

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1385-1386
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• 2005

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.2
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• pp.1-8
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• 2017

The purpose of this study is to examine the policy direction and execution plans of the Japanese central and local governments for the use of vacant houses after the enactment of the "Special Act on Vacant Houses." It also seeks to provide suggestions for establishing vacant house policies in Korea by identifying the characteristics of the Japanese policies, and to suggest policy alternatives that can contribute to environmental improvement and regional revitalization through the use of vacant houses. For this purpose, we examined Japan's "Special Act on Vacant Houses," the process of establishing vacant house policies in the Japanese central and local governments, and the contents and direction of these policies. Below are the results of this study. First, the Japanese government revised mid to long-term policies related to housing after the enactment of the "Special Act on Vacant Houses", thereby providing ground for local governments to establish vacant house policies. Second, the government actively supported the operation and funding of related associations so that the private sector rather than the public sector could address vacant house problems. Third, the government subsidized administrative expenses such as cost of finding vacant house owners to prevent neglect of vacant houses, and showed its will to address vacant house problems by revising taxes such as property taxes and transfer income taxes. Fourth, the government has enacted distinct ordinances for each local government and made it possible to perform customized policies such as allowing residents and local stakeholders to participate in the establishment of vacant house policies. Fifth, the government made it possible to manage vacant houses efficiently by allowing the vacant house bank to provide all information related to the use of vacant houses. It is necessary for Korea's central and local governments to refer to these precedent cases and create efforts to reduce trial and error when establishing vacant house policies.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.94-94
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• 2017

Oryza sativa and Oryza glaberrima are rice cultivars distributed in Asia and Africa. There are several differences between these cultivars in morphological characteristics such as panicle structure and especially the secondary branch number of O. glaberrima is less than that of O. sativa. Generally, branch number of panicle related to a large vascular bundle number (VBN) among O. sativa and there is a wide variation of the VBN of the peduncle from where the bundles enter into the rachis branches. However, there is less information about VBN in O. glaberrima and also the relationship between VBN and branch numbers, the primary branch number (PBN) and secondary branch number (SBN). Additionally, the genetic factor for VBN and branch number in O. glaberrima is not completely exploited. In this study, phenotypic variation for VBN and panicle structure were investigated using a set of 40 $BC_3$ -derived from IRGC 104038 (O. glaberrima from Senegal) and 35 $BC_4$ -derived from IRGC103777 (O. glaberrima from Mali) introgression lines with a genetic background of japonica rice Taichung 65. Taichung 65 had 11.8 PBN, 16.0 SBN and 11.5 VBN, while IRGC 103777 had 12.0 PBN, 15.0 SBN and 15.3 VBN. The introgression lines derived from IRGC 104038 had range from 9.0 to 14.4 in the PBN, range from 9.6 to 33.5 in the SBN and range from 9.8 to 14.8 in the VBN. Additionally, the introgression lines derived from IRGC 103777 had range from 9.0 to 18.5 in the PBN, range from 10.3 to 39.0 in the SBN and range from 9.0 to 15.3 in the VBN. Among two set of introgression lines, there are significant correlation between VBN and PBN. Multiple introgression lines indicated higher PBN, SBN and VBN than Taichung 65 and these examined characteristics are supposedly controlled by quantitative traits loci. The genetic factor related to VBN and panicle architecture can be revealed using segregating population in future study.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.4
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• pp.45-55
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• 2002

The purpose of this study is to suggest the way of analyzing land uses to utilize GIS in the field of urban planning. The Saga Land Information System was built in early 1990s. The building data were inputted by house investigation map(1/1,000) using digitizer. And urban planning basis investigation data in 1994 were utilized as the attribute data. Also, by calculating specialization factor, we distinct the characteristic of every land use of the city, and it compares every land use zone. This study calculated and compared an observation frequency and an expectation frequency of every building use and land use zone. We found that the use of the building tend to be controlled and guided by the land use zone.