• 한국수소및신에너지학회논문집
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• 제25권3호
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• pp.297-304
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• 2014

The purpose of this study is to evaluate the experimental performance characteristics of a water-to-water geothermal heat pump featuring a vapor refrigerant injection for the production of hot water. The performance of geothermal heat pump with a vapor injection was evaluated by comparing with that of a conventional geothermal heat pump without a vapor injection. For heating operation, the geothermal heat pump with a vapor injection is superior in COP and heating capacity. The vapor injection was more effective for supplying hot water while overloading. The vapor injection was effective for the improvement of the cooling capacity. However, the vapor injection was not effective for the increasing of COP according to the increased input of a compressor. The advantage of vapor injection in water-to-water geothermal heat pump become disappeared while cooling operation with lower part loading.

• 기술혁신연구
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• 제12권2호
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• pp.209-225
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• 2004

This study aims to explore and understand the role of knowledge intensive service activities in the industrial innovation of Korea. It analyzes public and private service inputs to the innovation of manufacturers. The contribution of KISs to the innovation of both service suppliers and manufacturers was analyzed by using survey questionnaire. The results of the analysis revealed that the contribution of KISs to the innovation capability of manufacturers is significant. Large manufacturers that hold internal capability to supply KISs are also active in using external KISs. The manufacturing firms that utilized KISs intensively proved to be more innovative than those did not. Heavy KISs users also entertained benefits of capability enhancement as they improved monitoring and achieved efficient application of knowledge asset into product and process innovation. The role of public KISs in the innovation of manufacturers appeared to be indirect and done mainly through education and public R&D activities. Direct input, such as public software service, was not utilized as much in service suppliers themselves. The major reason is that public KISs may not be relevant to their actual needs. Manufacturers have implemented both tighter integration of familiar KISs and loosely coupled unfamiliar KISs.

• 제어로봇시스템학회논문지
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• 제2권1호
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• pp.26-34
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• 1996

One of the challenging tasks in visual inspection using CCD camera is to identify surface defects in an image with complex textured backgeound. In microscopic view, the surface of real objects shows regular or random textured patterns. In this paper, we present a visual inspection algorithm to extract abnormal surface defects in an image with textured background. The algorithm uses the space and frequency information at the same time by introducing the Dominant Frequency Map(DFM) which can describe the frequency characteristics of every small local region of an input image. We demonstrate the feasibility and effectiveness of the method through a series of real experiments for a 14" TV CRT mold. The method successfully identifies a variety of infinitesimal defects, whose size is larger than $50\mu\textrm{m}$, of the mold. The experimental results show that the DFM based method is less sensitive to the environmental changes, such as illumination and defocusing, than conventional vision techniques.ques.

• Ocean and Polar Research
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• 제33권1호
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• pp.77-83
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• 2011

In this study we examined the economic value of restoration technology for oil spill using contingent value methods. One and one half approach to questionnaires can be taken when analyzing tax payer situations as well as single bound approach. The results of the empirical analysis suggest three conclusions. First, the economic value of the restoration technology considered are estimated to be between 8,439 won to 11,867 won per month. Second, the WTP is estimated differently depending on the approaches, OOHB and SB, and the degrees of difference are very sensitive to the model specifications. This empirical result supports the argument for using interval for the economic value when using CVM. Third, the empirical results may provide useful input to policy authorities attempting to estimate the economic justification of the R&D investment for developing an ocean environmental restoration technology.

• 정보관리학회지
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• 제17권2호
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• pp.155-170
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• 2000

본 연구에서는 효율적인 서지정보 데이터베이스를 구축하기 위한 여러 가지 방안들이 제시되었다. 대상 자료의 선정으로부터 입력 양식의 표준화 및 입력시스템의 활용 등에 이르기까지 다양한 요소들이 검토되었으며, 특히 대상 자료의 선정시에 고려하여야 할 부분을 중점적으로 다루었다. 입력 대상 자료의 우선 순위를 결정하기 위하여 이용자 정보요구의 파악이 비교적 용이한 원문복사 서비스 현황을 비교, 분석하였다. 이용현황에 대한 분석 결과 다양한 형태의 자료 가운데 가장 우선적으로 입력하여야 할 대상은 조사결과 Proceeding인 것으로 나타났으며, 학술지는 우선순위에서 그 다음을 차지하였다. 또한 학술지의 경우 학술지별 원문복사 신청 현황을 분석하여 SCI의 전체 인용빈도와 영향력 지수(Impact Factor)에 의한 순위와 비교ㆍ분석하였다.

• 조명전기설비학회논문지
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• 제27권12호
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• pp.133-140
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• 2013

Cascaded H-Bridge multi-level inverters can be implemented through the series connection of single-phase modular power bridges. In recent years, multi-level inverters are becoming increasingly popular for high power applications due to its improved harmonic profile and increased power ratings. This paper presents a control method for balancing the dc-link voltage and ride-through enhancement, a modified pulse width-modulation Compensation algorithm of cascaded H-bridge multi-level inverters. During an under-voltage protection mechanism, causing the system to shut down within a few milliseconds after a power interruption in the main input sources. When a power interruption occurs finish, if the system is a large inertia restarting the load a long time is required. This paper suggests modifications in the control algorithm in order to improve the sag ride-through performance of ac inverter. The new proposed strategy recommends maintaining the DC-link voltage constant at the nominal value during a sag period, experimental results are presented.

• Asian Journal of Innovation and Policy
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• 제7권2호
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• pp.287-309
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• 2018

The demand for efficient utilization of input resources and productive outcomes is increasing as the government's R&D investments in Government-funded research institutes (GRIs) expand. These changes call for improving research-planning activities, which are defined as a set of activities wherein objectives are established, strategies for acquisition and expenditures of research resources are devised, and utilizations of research outcomes are addressed. This study introduces the integrated 4P analysis model that identifies the relationships among patents, papers, products, and projects. It looks into 4P analysis structure and its efficiency as a research planning means through case studies of the Korea Research Institute of Chemical Technology. This study introduces 4P analysis applied to KRICT, which can be utilized for outcome-oriented research planning of GRIs. At the same time, it investigates into the benefits and implications of 4P analysis. It proffers policy suggestions on such aspects as how research planning of GRIs should go through changes in a strategic and systematic way.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 영호남학술대회 논문집
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• pp.74-77
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• 2000

A pulsed Nd:YAG laser has been used in a wide variety of fields : measuring, material processing and so on. In a material processing, it is very important to control the laser energy density. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, pulsed Nd:YAG laser system was designed and manufactured to control the laser output usefully and easily. This system adopted the sequential charge and discharge circuit is controlled by 80196 micro- processor. As a result, it is found that laser output is controlled minutely by changing laser input and pulse repetition rate, and usefully by using 80196 microprocessor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.546-551
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• 2001

Space Test Department at KARI(Korea Aerospace Research Institute) plans to carry out the GVT(Ground Vibration Test) for the KSR(Korea Sounding Rocket)-III FM(Flight Model) which is being developed by Space Technology R＆D Division. KSR-III will be an intermediate to the launch vehicle capable of carrying satellites to their orbits. GVT offers very important information to predict the behavior of KSR in its operation, and to develop the flight control and aerodynamic analysis. For development of test facilities, testing and analysis methods which can be used for the future test, Space Test Department has performed the GVT with KSR-II PFM(Proto-Flight Model) at Satellite Integration ＆ Test Center of KARl This paper discusses the procedures, techniques and the results of it. In this test, to simulate free-free condition, test object hung in the air by 4 bungee cords specially devised. The GVT was carried out using pure random excitation technique with MIMO(Multi-Input-Multi-Output) method with three electromagnetic shakers, and poly-reference parameter estimation was used to identify the modal parameters. As the result of the test, 11 mode shapes and modal parameters below 200㎐ were identified and compared with analytical results.

• 한국수소및신에너지학회논문집
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• 제21권1호
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• pp.64-71
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• 2010

This paper deals with an economic evaluation of domestic immersing type photoelectrochemical hydrogen production. We also make some sensitivity analysis of hydrogen production prices by changing the values of input factors such as the initial capital cost, the solar to hydrogen conversion efficiency, and the system duration time. The hydrogen production price of the immersing type photoelectrochemical system was estimated as 8,264,324 won/$kgH_2$. It is expected that the production cost by photoelectrochemical hydrogen production can be reduced to 26,961 won/$kgH_2$ if the solar to hydrogen conversion efficiency is increased to 14%, the system duration time is increased to 20,000 hours, and the initial capital cost is decreased to 10% of the current level. The photoelectrochemical hydrogen production is evaluated as uneconomical at this time, and we need to enhance the solar to hydrogen conversion efficiency and the system duration time as well as to reduce prices of the system facilities.