• Nuclear Engineering and Technology
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• 제53권4호
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• pp.1189-1198
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• 2021

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

• 산학경영연구
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• 제19권1호
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• pp.53-80
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• 2006

지역 중소건설업체의 주요 문제점은 업체수의 급격한 증가 추세와 이로 인한 심각한 수주경쟁 및 수익성 악화에 기인한다. 공공 공사의 대부분을 차지하는 대규모 토목공사와 지방자치단체 발주 공사 수주에 있어 대형 업체가 지방으로 진출함에 따라서 중소업체는 경쟁력 취약, 공사관리 시스템 부재 및 품질관리능력 미흡 등으로 어렵다. 또한 기술능력의 전문성 부족, 우수한 기술인력의 확보능력 및 기술 인력의 개발/관리능력 미흡, 자금조달의 어려움으로 인한 자체사업 및 개발사업 등의 사업확대 불가능, 발전 및 성장을 위한 기업의 특화된 전략과 목표가 취약하다. 지역 중소건설업체의 주요 개선방안은 첫째, 최고 경영자의 의식 변화를 통한 경영혁신이 필요(중소업체의 경우 대형업체보다 최고 경영자가 경영 성과에 미치는 영향이 매우 크게 나타나고 있다)하다. 둘째, 전문적인 기술력과 특화된 전문분야를 확보하여 차별적인 경쟁력을 구축해야 한다. 셋째, 전문 기술인력의 확보 및 확보된 내부인력을 관리 육성하기 위한 시스템의 개발이 필요하다. 넷째, 재무관리 능력의 개선 및 자금조달 능력 향상을 통한 경영 차원의 개선과 개발사업, 자체사업 등으로의 사업영역 확대 등이 요구된다. 도출된 문제점과 개선방안을 토대로 살펴보면 강원지방 중소건설업의 성장전략은 다음과 같은 것이 중요하다. 공공부문과 민간부문 그리고 자체사업 분야의 성공적 확대를 위해서 가장 필요한 성장전략은 품질 확보와 가격경쟁력이다. 현재 공공 및 민간부문의 수준확대를 위해서 확대해야 할 기반분야는 발주기관과의 유대관계 확립과 기술경쟁력 확보 그리고 정보시스템의 도입 등이다. 향후 수행하여야 할 사업에서 주력해야 될 사업경쟁요소는 품질, 기술, 가격 등이다. 향후 중소건설업체의 성장을 위한 사업경쟁 요소는 최우선적으로 기술과 품질로 이의 개선을 위한 정보화 기반의 구축과 확대가 필요하다.및 24시간 전에 조사하였던 UVB의 영향인 것으로 생각된다. 24시간 간격으로 10분간씩 3회 조사했을 때 중족골의 Ca 함량은 점차 증가되어 96시간에 최고치 24.18%를 보였고 P함량은 역시 96시간에 최고치 7.29%를 나타내었으며, 회분 함량은 240시간까지 계속 증가되어 45.73%에 이르렀다. UVB조사 후 경과시간에 따라 살펴보면 중족골의 Ca와 P 함량은 UVB 조사후 96~144시간에 최고치에 도달했으나 회분함량은 240시간까지 계속 증가하는 모습을 보였다. 다음 UVB의 조사방법에 따라 종족골의 Ca함량을 봤을 때 무간격으로 조사시 240시간까지 계속 증가하였고, 12시간 간격으로 조사시 144시간에 최고치를, 24시간 간격으로 조사시에는 96시간에 최고치를 나타내었으며 회분 함량을 봤을 때 12시간 또는 24시간 간격으로 조사하였을 경우가 무간격으로 조사하였을 때보다 더 높은 수준을 보였으므로 24시간 간격으로 10분간씩 조사하는 것이 바람직한 것으로 생각되었다.를 미루어 볼 때 과산화된 지질의 섭취는 생체내 대사 이상을 유발할 가능성이 인식되었고 카테킨의 투여는 신선한 어유를 섭취한 경우 뿐만 아니고 이미 과산화된 어유를 섭취한 경우 뿐만 아니고 이미 과산화된 어유를 섭취한 경우에도 생체내에서 과산화 억제작용을 어느 정도 효과적으로 수행하는 것으로 나타나 앞으로 이의 효과적인 활용이 기대된다.다.nsidered to be due to the different food habits and environmental condition of the invertebrates.재강조될 필요가 있다. 이 두 역할개념 들을 교육을 통하여 효과적으로 가르칠 필요가 있다고 본다. 이 두 개념들이 간호사의 바람직한 간호행 위에 영향을 미치는 가장 중요한 요소로 나타났기 때문이다. 또한, 본 연구결과에 따르면, 경험이 많을수록

• 통상정보연구
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• 제11권3호
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• pp.125-144
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• 2009

The purpose of this study is to research the investment environment of Vietnam and analyze the actual investment state of Korean enterprises in Vietnam and seek for the points at issue. In general, the investment environment in Vietnam shows both a positive side and negative side. However Vietnamese market is a attractive one as ever for direct investment of Korean enterprises considering their constant economy growth, investment increase of foreign company for Vietnam, China risk. And the point at issue in investment of Korean Enterprises is as follows. That is, inclining to manufacturing, preference of independence investment, small-sized investment by small and medium enterprises, preference of greenfield investment, restricted purpose of investment, insufficiency of infrastructure for logistics, electric power, legal system. The results of the study indicate mainly that the investment of Korean enterprise into Vietnam needs a switchover of the third service trade-tertiary industry, collaboration with Vietnamese enterprise through joint venture investment, a large-scale investment for Vietnam domestic market and neighboring countries' market, practical use of M&A with existing Vietnamese enterprise and diverse purpose for investment.

• 한국정보보호학회:학술대회논문집
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• 한국정보보호학회 2006년도 하계학술대회
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• pp.219-222
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• 2006

In this paper an intrusion detection system technique of wireless Ad Hoc network is explained and the advantage of making them work in IEEE 802.15.4/ZigBee wireless standard is also discussed. The methodology that is mentioned here is intrusion detection architecture based on a local intrusion database [1]. An ad hoc network is a collection of nodes that is connected through a wireless medium forming rapidly changing topologies. Due to increased connectivity (especially on the Internet), and the vast spectrum of financial possibilities that are opening up, more and more systems are subject to attack by intruders. An ideal IDS should able to detect an anomaly caused by the intruders quickly so that the misbehaving node/nodes can be identified and appropriate actions (e.g. punish or avoid misbehaving nodes) can be taken so that further damage to the network is minimized

• Journal of Advanced Marine Engineering and Technology
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• 제37권7호
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• pp.694-700
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• 2013

The design of the exhaust manifold for the pulse converters of a 4 strokes high power medium-speed diesel engine is presented in terms of fatigue analysis. The said system undergoes thermal expansion due to high temperature of exhaust gas and is exposed to intrinsic vibration of the internal combustion engine. Moreover, the exhaust pulse generates pressure pulsating along the runner inside manifold. Under such circumstances, the design and construction of exhaust manifold must be carried out in a way to prevent early failure due to fracture. To validate the design concept, a test rig was developed to simulate the combination of thermal and vibrational movements, simultaneously. Experimental results showed that a certain sense of reliability can be achieved by considering a field factor obtained from the results of engine bench tests.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.801-804
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• 2002

Electrochemical capacitors are becoming attractive energy storage systems particularly for applications involving high power requirements such as hybrid systems consisting of batteries and electrochemical capacitors for electric vehicle propulsion. Both of amorphous cobalt oxide and manganese dioxide were prepared by sol-gel process reported in our previous work. Nanostructured supramolecular oligomer of 1,5-diaminoanthraquinone(DAAQ) coated metal oxides were successfully prepared by electrochemical oxidation from an acidic non-aqueous medium. We established process parameters of the technique for the formation of nano-structured materials. Furthermore, improved the capacitive properties of the nano structured metal oxide electrodes using controlled solution chemistry. $CoO_2$ and $MnO_2$-based composite electrode showed relatively good electrochemical behaviors in acidic electrolyte system with respect to specific capacity and scan rate dependency.

• 한국에너지공학회:학술대회논문집
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• 한국태양에너지학회, 한국에너지공학회 1993년도 춘계 공동학술발표회 초록집
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• pp.126-131
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• 1993

Differential Scanning Calorimetry (DSC) and solvent swelling technique have been applied for identifying physical transition temperatures in the macromolecular structure of coals. The transition processes seem to be associated with physical relaxation of the coal structure and are irreversible processes. In Pittsburgh No. 8 high volatile bituminous (hvb) coat one physical transition was noted at 250-30$0^{\circ}C$ (at 8$^{\circ}C$/min) without any significant accompanying weight loss. Coals of higher rank than high volatile bituminous, i.e., Upper Freeport medium volatile bituminous (mvb) and Pocahontas No.3 low volatile bituminous (lvb) coals, exhibit structural relaxation just before the major thermal decomposition process and a sharp increase in solvent swellability accompanies this relaxation. In the case of both the Pittsburgh No.8 and the Upper Freeport coat structural relaxations at around 36$0^{\circ}C$ seem to coincide with release of "guest molecules".les".uot;.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.326-329
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• 2003

When an electrokinetic process is applied to a HOC-contaminated soil, hybrid types combined with soil flushing, chemical oxidation, and bioremediation are generally used. Especially when the electrokinetic process is combined with bioremediation, the hybrid technology can solve several limits of bioremediation such as low microbial mobility, low soil temperature, and shortage of nutrients in subsurface circumstance. Because microbial surface is charged negatively, the microorganism moves from cathode to anode under electrical field. In this study, mixed culture mainly-consisted by Pseudomonas sp. was applied to remediate pentadecane-contaminated kaolinite with particle size less than 300${\mu}{\textrm}{m}$. This remediation system was named ‘electrokinetic bioaugmentation’ and consisted of model aquifer, electrode reservoirs, bioreactor, power supply, and pump. The mixed culture above 0.5 of optical density in bioreactor was supplied to two reservoirs and penetrated soil when the electric current was applied. To enhance the removal efficiency, the optimal medium composition, electric current, and voltage were investigated.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.158-162
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• 1995

Synergistic effects of mixed solvents, especially with mixtures of CS$_2$ with electron donor solvents, in inducing desired structural changes in coals were studied by solvent swelling techniques in addition to differential scanning calorimetric analyses. Mixed solvents exhibit significant synergistic efficacy in swelling the coal structure of medium bituminous rank. This synergy effect appears to be physical origin that is closely related to matching solubility parameters. Since the swollen coal structure can be obtained by mixed solvents with CS$_2$ at room temperature instead of high temperature, many possible technological pathways for economical utilization of coal might be sought.

• International Journal of Advanced Culture Technology
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• 제3권1호
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• pp.101-112
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• 2015

Renewable energy resources play an important part in the world's future. Renewable energy sources have the following components: biomass, geothermal, solar thermal, directs solar, wind, tidal and hydropower. Hydropower is still the most efficient way to generate electricity worldwide. Hydropower projects can contribute as a cheap energy source, as well to encourage the development of small industries across a wide range of new technology; furthermore hydropower systems use the energy in flowing and falling water to produce electricity or mechanical energy. Hydropower systems are classified as large, medium, small, mini and micro according to their installed power generation capacity, as do the following components: water turbines, control mechanisms and electrical transmissions. In this article a review of small hydropower systems has been done on the principles surrounding the fundamentals of hydraulic engineering, the fundamentals of hydrology, identification of sites and economic analysis.