• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.27-36
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• 2014

This paper presents an adaptive wide-area damping controller (WADC) based on generalized predictive control (GPC) and model identification for damping the inter-area low frequency oscillations in large-scale inter-connected power system. A recursive least-squares algorithm (RLSA) with a varying forgetting factor is applied to identify online the reduced-order linearlized model which contains dominant inter-area low frequency oscillations. Based on this linearlized model, the generalized predictive control scheme considering control output constraints is employed to obtain the optimal control signal in each sampling interval. Case studies are undertaken on a two-area four-machine power system and the New England 10-machine 39-bus power system, respectively. Simulation results show that the proposed adaptive WADC not only can damp the inter-area oscillations effectively under a wide range of operation conditions and different disturbances, but also has better robustness against to the time delay existing in the remote signals. The comparison studies with the conventional lead-lag WADC are also provided.

• Journal of the Korean Society of Clothing and Textiles
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• 제14권4호
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• pp.292-304
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• 1990

The surface change of upperarm and shoulder blade area are caused by the extensive upper limb movement, thus it is necessary to measure the amount of change for constructing the clothing. Moire photography was taken after plastic casters of upperarm and shoulder blade area was prepared. 1. For the shoulder blade area, subjects showed the same change of surface area for the various limb positions, wherease, for the upperarm only at the $0^{\circ}\;and\;180^{\circ}$ limb position, same change was observed. 2. As the movement of the upperarm was increased, surface area of axillary part was increased and that of shoulder part was decreased. 3. To make a bodice pattern, the minimum size of the back with the ease were $\frac{B}{4}$+3.13 cm R for normal wear and $\frac{B}{4}$+5.75 cm for active wear. 4. As the movement of the arm was increased, the cross section for the upperarm were changed to elliptical shape. 5. For each horizontal basic line, there was a positive correlation between the amount of change of shoulder blad area and that of upperarm area.

• Journal of Korean Society of Rural Planning
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• 제17권2호
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• pp.13-21
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• 2011

The federal government has been implemented several housing policies attempting to improve living quality at Eup-Myun area(rural area), but those were mostly fund supports to reconstruct or repair houses. Existing minimum housing standard is focused on urban apartments and indoor space, but the houses of Eup-Myun area are scattered and are different from urban's house space. Therefore, this study focused on these area, and intended to propose suitable minimum housing standard for Eup-Myun area. Based on literature reviews about housing standard of England, U.S., Japan and South Korea, questionnaire survey was given to 50 experts divided into 2 groups, professors of architecture and researchers on rural environment. This study proposed the direction of new minimum housing standard of Eup-Myun area, it could be added to 2 household composition, be divided into 2 groups, agricultural and non-agricultural residents into facility guideline, be added to outdoor facilities, for example warehouse and open yard, and finally be inserted water quality into environment standard. The results of this study provide insightful strategies for rural housing standard.

• Journal of Environmental Impact Assessment
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• 제20권2호
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• pp.141-150
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• 2011

The construction of photovoltaic complex in mountainous area is quickly increasing recently so that the environment assessment in constructing photovoltain complex in mountainous area was performed by comparison of $CO_{2{\cdot}}$ reduction and forest damage. The case studies for environmental value assessment, which construct photovoltaic complex in mountainous area, show that the losses of around 5.1billion won arise during 15 years. The government's official target for spreading photovoltaic energy until year 2030 can be satisfied when considering other alternative sites, improvement of technology and the alternative sites of an idle space of a building or a disused site, etc, except an undeveloped mountainous area. The construction of photovoltaic complex in mountainous area can cause the great damage to the environment, especially undeveloped mountainous area such as Baekdudaegan, and this defeat its own purpose of using photovoltaic energy. Therefore, the spread of photovoltaic complex through the additional damage of forest should be sublated.

• Journal of the Korea Society of Computer and Information
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• 제13권3호
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• pp.85-90
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• 2008

In this paper, we propose a new robot cleaning algorithm, which we call SetClean. The new algorithm cleans from the most less complex area. Sometimes, when the cleaning completion time can be longer or can not be estimated, cleaning larger area first is better than optimizing the whole time for cleaning. To do this, SetClean algorithm divides the whole area into cleanable sub-areas using Set Cover algorithm and cleans the area in the order of high efficiency that maximize the cleanable area per unit time. SetClean algorithm decides the navigation flow by considering not only the size of the area but also the distance from the current robot location to the area to be cleaned and the delay time caused by the number of turns within the area. The experimental results show the mechanism and performance of the SetClean algorithm.

• Journal of the Korean housing association
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• 제18권5호
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• pp.93-102
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• 2007

The purpose of this study is to explore the changes in space structure in urban residential areas, based on the historical and cultural background of Gyeongju area. In order to clarify its residential and cultural properties, the residential patterns and living characteristics identifying its historical context were analysed. This study was carried out with the data of the Hwango-dong area that has maintained its original form since the creation as a urban residential area during the 1960s and 1970s, the data of the Dongbang village area that was developed as one of residential area projects during the 1970s, and the data of the Seonggeon-dong area that was developed as a residential area during the 1970s and 1980s. The analyses on previous studies and statistical data, referring to building administration registers, field survey and photographing of house types, and exploration of living characteristics by house types were used to perform this study. Four hundred and five sample houses were used in this study, having forty one sample houses which were used for living survey and actual plane measurement. The result of this study can be used as basic information for designing the house to meet Gyeongju citizens' desire for living environments, and to maintain the cultural and historical contexts.

• KIEAE Journal
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• 제10권1호
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• pp.109-116
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• 2010

The city means not only a geographical area as a role of the spatial boundary, but also a socio-economic place to communicate with each area. It requires various functions to get the income and economic-activities. But city has a limitation of a available land to provide the required functions and a sufficient space to supply the urban activity. Therefore, the development trend of city has not been to spread to the horizontal area any more and considered the vertical area. In addition, various functions put into a massive building because many people want to solve the daily requirements without spending time and cost in outer area. In this paper, it aimed at classifying the mixed-use building into function, circulation, relation according to the public and private space and the building shape to provide the design information such as land area, functional complex, accessibility, etc.. The classification of the mixed-use buildings is divided into four areas. The data are collected with foreign countries in Japan, Europe and US. Results of the study are as follows; First, the commercial function is mainly centered with other functions. Second, after studied the development scale, accessibility, building form, the commercial and residential area overwhelmly share at the total area.

• Journal of the Korean Society of Safety
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• 제20권3호
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• pp.71-77
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• 2005

This study aims to find the safe vent area to prevent a destruction of building by gas explosion in a building. Explosion vessel which used in this experiment is 1/5 scale down model of simple livingroom and its dimension is 100cm in length 60cm in width and 45cm in height. Liquified petroleum gas(LPG) was injected to the vessel to the concentration of 4.5vol%, and injection rate were varied in 1L/min or 4L/min. Gas mixture was ignited by the 10kV electric spark. For analysis the characteristics of vented explosion pressure according to the vent size and vent shape, its size and shape were varied. From the experiment, it was found that explosion pressure in the vented explosion :in affected by the gas injection rate, vent area and vent shape. And the vent area to volume ratio(S/V) to prevent the building destruction by explosion pressure, it is recommended that the design of vent area happened by the explosion should be above 1/500cm in S/V. And if the vent area has complicate structure in same area, vented explosion pressure will be higher than a single vent, and possibility of building destruction will increase. Therefore to effectively vent the explosion pressure for protect a building and residents from the gas explosion hazards, the same vent area should have a singular and constant shape in the cross-sectional area of the vessel.

• Journal of the Korean Institute of Landscape Architecture
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• 제17권3호
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• pp.35-47
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• 1990

This study was executed to analyze the vegetational landscape structure and administration planning of Heonin Royal Tomb forest by three kinds of ordination techniques (PCA, RA and DCA) and comparison of the couple photographs between 1920s and 1980s. Seventeen sites in the recreation area and fifteen sites in the protective area were sampled with clumped sampling method in June 1988 and five quadrats were examined in each site. Environmental impact grade 3, 4 and 5 area covered 56.4% of the surveyed area and these area should be restored by the input of human energy. Pinus densifora community of actual vegetation covered 8.4%, Alnus japonica 24.2% and Quercus community 40.9% of the total area. And the afforested vegetation of Pinus koraiensis and Pinus rigida covered 23.1 % The recreation area was divided by P. densiflora, P. densiflora-Quercus aliena, A. japonica-Q.aliena, A. japonica and the protective area by Q. acutissima, Q. aliena, A. japonica-Q. aliena.. DCA ordination showed that successional trends of tree species seem to be from P. densiflora, Sorbus alnifolia, Styrax obassia to Q. variabilis Q. serrata in P. densiflora community and from A. japonica through A. ginnala to Q. aliena in A. japonica community of the upper layer. By the comparison of the couple photographs between 1920s and 1980s, we can recognize the change of historical landscape composed of P. densiflora community and those community is succeeded to Q. aliena.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제17권1호
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• pp.175-182
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• 2013

The digitalization of sea level measurement recording which is recorded as analog type is useful for many related oceanology. In this paper, we propose a method which separates the graph area from a sea level measurement recording image. At first, a pixel that is regarded as the pixel which is included in the graph area is selected. Then, many background pixels are separated using the color of the selected pixel. In each vertical line, a pixel is determined as the pixel within the graph area and the graph area is separated from the image using that pixels. Experimental results show that the proposed method in this paper overcome drawbacks of the previous research and can separate the graph area which similar to the graph area of the original image.