• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.302-307
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• 2010

Development of light-weight high speed train (HST) based on distributed motor control with the top speed of 350 km/hr has engendered a need for abatement of the interior noise of the train cabin. The development of noise abatement measures is crucial at the design stage of the train car since the noise transmission characteristics of the car structure directly influences the cabin interior noise. Since the transmission loss measurement using the entire car structure is often not feasible, especially at the initial stages of the train development, investigation of transmission characteristics using small-scale reverberation chamber can furnish useful alternative source of predicting the noise level. In the present study, white noise is generated at source and transmission loss estimated by performing measurement of a specimen in a scaled reverberation chamber. Comparison of measured values with the previously derived numerical values show good agreement in the overall trend but appreciable quantitative differences still remain.

• 한국전기전자재료학회논문지
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• 제33권4호
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• pp.326-330
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• 2020

Small-scale production control systems for smart manufacturing are becoming increasingly necessary as the manufacturing industry seeks to maximize manufacturing efficiency as the demand for customized product production increases. Correspondingly, the development of an embedded system to realize this capability is becoming important. In this study, we developed an embedded system based on an open source system that is cheaper than a widely applied programmable logic controller (PLC)-based production control system that is easier to install, configure, and process than a conventional relay control panel. This embedded system is system is based on a low-power, high-performance Cortex M4 processor and can be applied to smart manufacturing. It is designed to improve the development environment and compatibility of existing PLCs, control small-scale production systems, and enable data collection through heterogeneous communication. The real-time response characteristics were confirmed through an operation test for input/output control and data collection, and it was confirmed that they can be used in industrial sites.

• 한국해양공학회지
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• 제22권4호
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• pp.78-83
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• 2008

In recent years, small boats used for marine leisure have been steadily increasing because of the increase in national income and the desire for marine leisure. But the repair of such small boats in dry dock has pointed out many faults in small FRP-shipbuilding in terms if workspace and manpower. Lifting a boat from the water to land is done with a crane or by hand using a sling around the bottom of the boat. But dry dock work is limited by the scale of the boat, which corresponds to the crane capacity, with carelessness making it possible to capsize a boat and endanger life. The purpose of this study was the development of a marine docking system that would improve economical efficiency and safety, for which we carried out concept design, model tests, structural analysis, etc.

• 농촌지도와개발
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• 제24권1호
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• pp.1-8
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• 2017

The Purpose of this study is to predict farm size per farming household in Chungcheongnam-province by using the Markov chains and Quadratic Programming.. The results are as follows; First, small-scale farms with less than 1.0ha of land are predicted to be still more than half (of total farming households) in 2025 as well. Second, large-scale farms with 3.0ha-5.0ha land and extra large-scale farms with over 5.0ha of land are predicted to gradually expand their proportion in total farm scale. Third, middle-scale farms with 1.0ha-3.0ha land are forecasted to be reduced in their relative proportion. It is required to take into account regional characteristics to improve the effectiveness of a rice industry policy. Therefore, this study has some significance in attempting to research on the ownership structure of rice production areas in consideration of target regions.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.777-780
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• 2005

The bench of cut-slope is necessary to stabilizing. But it is possible to be a weak zone in slope. When a small scale failure is occurred in a bench, it influence a large scale failure of slope. So when it is found out any unstable factor, weathering of rock, a direction of joint in a bench, if the bench is reinforced suitably, the holly failure is prevented in cut-slope

• 유통과학연구
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• 제12권11호
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• pp.55-65
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• 2014

Purpose - This study aims to investigate the process of political changes in Japan, which has introduced regulatory policies for large-scale retail stores since the 1930s, as well as the examples, and suggests improvement schemes for our policies in Korea, which imposes restrictions on business hours and forced holidays in accordance with the current Distribution Industry Development Act. Research design, data, and methodology - After examining the political change processes related to large-scale retail stores in japan, this study analyzes individually regulated cases based on the ordinances enacted by each local government. Through case analysis in Japan, this study makes political suggestions that may be helpful for our country substantially. Results - Since there is an obvious possibility that our economic restrictions on business hours and mandatory holidays do not coincide with WTO GATS, it is necessary for large-scale distributors to introduce new social and environmental regulations similar to Japan, rather than imposing controls to restrict free competition and also introduce a policy to induce cooperation with small businesses for the advancement of the distribution industry. Thus, it is desirable to take measures on noise, waste, traffic, and parking for the preservation of the living environment in the surroundings when building new large-scale retail stores. It is also important to establish measures to improve the welfare of neighborhood residents and consumers, create a pleasant urban environment, and make it mandatory to make presentations at public hearings among residents. Furthermore, it should be mandatory to establish regional contribution plans when a retail store is established, and take measures to solve various civil complaints or problems that may occur after entering the market. Moreover, it is desirable for large-scale retail stores that entered the market to induce cooperation in performing various activities in the area with a strong sense that they are all members of the local economy. Conclusions - If introducing social regulations like in Japan, there is probably an advantage that the conflicts seen when large-scale retail stores enter the market are absorbed by adjusting the persons concerned within the established institution in order to establish a field to solve such conflicts systematically. In contrast, there are still concerns regarding chaotic operation without any active attempts to have a conversation with large-scale retail stores and local small merchants due to a sharp conflict among the persons concerned, and if it is a briefing session without any decision of the restrictions on their opening itself, there may be doubts with regard to their effectiveness. Moreover, if the de facto opening is restricted by the introduction of such a briefing session procedure, the choice of whether to protect the existing rights of large-scale retail stores might become problematic. However, such problems could be minimized in a way by forming a separate consultative group for all persons concerned including residents, local governments, professionals, civic organizations, small merchants, and massive retail store-related persons.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.821-824
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• 2009

LFG-MGT CHP system development project with $CO_2$ enrichment in greenhouses was introduced. LFG is produced from the anaerobic digestion of landfilled waste and it has been utilized for power/heat generation since it contains around 50% of $CH_4$. Utilization of LFG from small scale landfill is also needed as well as large scale landfill. However, due to economy of scale, it is very difficult to develop business model. In this context, combining CHP system with greenhouses is considered as feasible option for LFG utilization. LFG-MGT CHP system with $CO_2$ fixation in greenhouses has been derived as an active greenhouse gas reduction strategy, The focus of the system is beyond carbon neutral LFG utilization to neutral carbon absorption. The system is feasible in terms of direct and indirect $CO_2$ emission reduction with more economical way.

• 한국항만학회지
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• 제11권1호
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• pp.101-112
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• 1997

A Teleport is an integrated facility that provides its users with fast, convenient access to advanced telecommunicatoins by satellites, fiberobtics, microwave and other networks. A teleport town is an urban sub-center equipped with teleport and other telecommunication infra-facilities. This study is based on the explicit disclimination between these two related concepts. In this paper we classify various types of teleport town with respect to the specific conditions and situation in Korea. The teleport town which will be developed in Korea should be fitted into the balanced regional structure to boost up the effects of urban or regional development plan. Three models of teleport town(large scale, middle scale, small scale) are proposed on the basis of the classified types of teleport town.

• 대한기계학회논문집B
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• 제37권10호
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• pp.919-926
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• 2013

본 연구에서는 소형 저온 유기랭킨사이클 시스템의 작동특성을 파악하기 위하여 R-245fa를 작동유체로 사용한 소형 ORC 발전 시스템을 설계 및 제작하였고, 다양한 저온의 열원온도에 대한 실험적 연구를 수행하였다. 저온 열원을 모사하기 위하여 최고 $150^{\circ}C$의 물을 공급할 수 있는 110 kW급의 전기저항 히터를 제작하였으며, 컨트롤러를 통해서 다양한 열원 온도 및 유량조건에 대한 실험이 가능하도록 구성하였다. 또한, 상용 공기용 스크롤 압축기를 이용하여 팽창기로 개조하고 동력계 및 동기식 모터와 직접 연결하였다. 로드뱅크 및 PI 제어방식을 사용하여 팽창기의 회전속도에 따른 동일 열원온도 조건에 대한 실험을 각각 수행하였으며, 소형 ORC 시스템의 성능에 영향을 미치는 다양한 인자들에 대하여 분석하고 논의하였다.

• 한국환경과학회지
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• 제11권12호
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• pp.1217-1226
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• 2002

This study aims at the effective estimation of water supply capacity of small scale reservoir and the proposal of the data which is necessary to establish the water resources management plan of down stream area of the reservoir in the future by comparison and examination about reservoir operation technique for the security of agricultural water in small scale reservoir. The result of flow calculation by Tank model is used for the input data as the inflow data which is needed for the analysis of water supply capacity. Stochastic method, simulation method, and optimization method are used to examine the water supply capacity, and water security amount is compared with each method. From the analyses of water supply capacities by each method, slightly different results are shown in spite of the effort to compare them equally using input data such as inflow data under equal conditions, and the comparison of water supply capacities by each method are as follows; linear planning method, simulation method, and transition probability matrix method in the order of amount from the largest. It is thought that the simulation method in which comparatively reasonable application of the inflow data is possible and is simulated in successive time series dam operation of the three methods used in this study thus, simulation model is proper to estimate the water supply capacity of agricultural small scale reservoir. And it is judged that the heightening of efficiency of water resources utilization according to the development of downstream area of dam may be possible using the upward readjusted water supply amount of $55.18{\tiems}10^6ton$ and $63.7{\times}10^6ton$ at 95% and 90% supply reliability respectively which are above the planning water supply amount of $50.0{\times}10^6$ton when the simulation method is introduced as the standard.