• 수산해양기술연구
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• 제31권4호
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• pp.402-412
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• 1995

본 연구의 결과를 요약하면 다음과 같다. (1) 유압 펌프, 유량조절 밸브(오리피스)등을 주된 구성 요소로 하는 구조가 간단하고, 운전.관리가 용이한 유압식 풍력.열 변환 장치를 개발하였다. (2) 실험 결과로부터 본 장치의 에너지 변환 효율이 매우 높음을 확인하였다. (3) 출력 에너지가 열 에너지이므로 온수 탱크를 사용하여 쉽게 에너지를 저장할 수 있음을 실험적으로 확인하였다. (4) 본 장치는 대량 생산되는 유압 부품들만을 사용하여 구성이 가능하므로 매우 저렴한 가격으로, 신뢰성이 우수한 장치를 제작할 수 있다

• 한국환경과학회지
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• 제6권5호
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• pp.473-480
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• 1997

Microorganisms producing bioemulslfiler were isolated from the sea water In Pusan coastal area. The isolated strain which had the highest emulsification activity and stability was identified as the genus Achetobacter from the results of morphological. cultural and biochemical tests and named Achetobacter sp. EL-C6 for convenience. The compositions of optimum medium for emulsification of crude oil by Acinetobacter sp. EL-C6 were crude oil 2.0%, NH4NO3 0.2%, $K_2HPO_4$ 0.01%, $MgSO_4$.$7H_2O$ 1.o%, $CaCl_2$.$2H_2O$ 0.1% and NaCl 3.0% at initial pH 7.5 and 3$0^{\circ}C$, respectively. The cultivation for emulsification of crude ell was carried out in 500m1 shaking flask containing 100m1 of the optimum medium at 3$0^{\circ}C$. The highest emulsification was observed after 5 days. The utilization on the various hydrocarbon of the Achetobacter sp. EL-C6 showed that utilization of n-alkane compounds were better than that of aromatic compounds. Among the petroleum compounds, crude ell was best utilized by the Achetobacter sp. EL-C6.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.98.2-98.2
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• 2011

For optimal performance of a proton exchange membrane fuel cell (PEMFC), the membrane electrode assembly (MEA) requires hydration, and the membrane's conductivity depends on water content. A humidifier is required to ensure that the reactant gas, usually hydrogen and air, is hydrated before entering the fuel cell. Dry membrane operation or improper hydration causes performance degradation. Typically, the humidification of a fuel cell is carried out by means of an internal or external humidifier. A membrane humidifier is applied to the external humidification of transportation or residential power generation fuel cell due to its convenience and high performance. In this study, The experiments were constructed with a plate-type membrane humidifier in terms of geometric parameters and operating parameters. The results show that the temperature and pressure, the channel length, the membrane thickness and gas flow rate are critical parameters affecting the performance of the humidifier.

• 한국의류학회지
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• 제41권5호
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• pp.901-913
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• 2017

This study analyzed the current state of art by investigating related patents of cycling wear, and suggested fundamental data to develop clothing - originated in Korea. Patent trends were then analyzed after the related patents applied in Korea, USA, and Japan from 1975 to 2015 were extracted using WIPS ON, classified as nation, applicant, technology, use, and technological maturity of the applicant country. The number of patent applications has steadily increased since the 1990s, and has steeply grown since the 2000s. The USA accounted for 55.6% of all collected patents in the study, Japan for 30.6%, and Korea for 13.7%. Technologies related to patterns and functional materials have been dominated by the USA and Japan; however, smart technologies have been actively developed in Korea. According to use, USA focused on functionality, Korea concentrated on safety, and Japan uniformly combined functionality, safety, and convenience. According to the positioning of technology by application, water repellency, stretchability, muscle strengthening, pad, panel, finishing, and weaving technologies were positioned in the functionality.

• 한국안전학회지
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• 제30권5호
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• pp.29-36
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• 2015

Common utility tunnel is essential to the daily lives of people underground utilities (electricity, gas and supply facilities such as water, communication facilities, sewer facilities, etc.) to improve the appearance by co-acceptance and disaster prevention, important for the conservation of the city's population was concentrated road construction the city-based facilities. There is recognition of the importance of the various supply treatment facilities in common utility tunnel as infrastructure to accommodate joint according to the city expanded, the demand for infrastructure. In this paper, a cost-benefit analysis using a one-time occurrence, without simply relying on cost or current cost, project manager for the city-dimensional feasibility study conducted, the user level of the maintenance costs and user costs, including social costs items from various angles can be investigated and proposed a mechanism of economic feasibility common utility tunnel. Evaluation of the proposed technique is cost-benefit and cost caused by installing common utility tunnel the existing pipeline area - was investigated by the benefit analysis, extended and repeated common utility tunnel installation depends much affected by the excavation, so users of reducing the number of repeat excavation convenience can be seen that this occurs.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.535-538
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• 2004

최근 공동주택(아파트)의 품질에 대한 관심이 높아지고, 대형 구조물들이 건축물의 옥상부분을 활용하려는 인식의 변화와 더불어 옥상 방수의 재료와 공법에 대하여 관심이 증대되고 있다. 현재 까지 구조물의 유지관리 및 사용상의 편의를 위해 많은 방수 재료 및 공법이 개발되어 왔으나 여러 가지 기존의 방수하자 요인에 대하여 충분히 대응할 수 있는 방수 재료 및 공법이 미흡한 실정이다. 더욱이 옥상 방수에 있어 바탕상태 및 콘크리트의 물리적 거동으로부터 자유로울 수 있는 공법의 개발이 시급한 실정이다. 따라서 본 연구는 기존의 대표적인 옥상 방수 공법에 대하여 알아보고 문제점을 분석함으로써 옥상 방수 에 대한 새로운 방향으로의 시야를 넓혀보고자 한다.

• Computers and Concrete
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• 제19권5호
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• pp.501-507
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• 2017

The predictive utility of a damage model depends heavily on its particular choice of a damage variable, which serves as a macroscopic approximation in describing the underlying micromechanical processes of microdefects. In the case of spatially perfectly randomly distributed microcracks or microvoids in all directions, isotropic damage model is an appropriate choice, and scalar damage variables were widely used for isotropic or one-dimensional phenomenological damage models. The simplicity of a scalar damage representation is indeed very attractive. However, a scalar damage model is of somewhat limited use in practice. In order to entirely characterize the isotropic damage behaviors of damaged materials in multidimensional space, a system theory of isotropic double scalar damage variables, including the expressions of specific damage energy release rate, the coupled constitutive equations corresponding to damage, the conditions of admissibility for two scalar damage effective tensors within the framework of the thermodynamics of irreversible processes, was provided and analyzed in this study. Compared with the former studies, the theoretical formulations of double scalar damage variables in this study are given in the form of matrix, which has many features such as simpleness, directness, convenience and programmable characteristics. It is worth mentioning that the above-mentioned theoretical formulations are only logically reasonable. Owing to the limitations of time, conditions, funds, etc. they should be subject to multifaceted experiments before their innovative significance can be fully verified. The current level of research can be regarded as an exploratory attempt in this field.

• 한국유체기계학회 논문집
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• 제8권4호
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• pp.14-19
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• 2005

Average Bi-directional flow tube was suggested to measure single and two phase flow rate. Its working principle is similar with Pilot tube, however, it makes it possible to eliminate the cooling system which is normally needed to prevent from flashing in the pressure impulse line of Pilot tube when it is used in the depressurization condition. 3-dimensional steady state flow analyses using FLUENT 5.4 code were performed to validate the application of the average bi-directional flow tube in case of water and air flow. In this study, sensitivity studies have been performed to optimize the design features of the average bi-directional flow tube which can be applied for the various experimental conditions. For Re numbers above 1000, the k values are nearly constant regardless of the Re numbers and flow types and calculation results and experimental data coincides quite well. The current FLUENT calculation results suggest that linearity of the k values in various design features of the average BDFT is highly promising, which means that it is quite reasonable to select the typical design of the average BDFT for the convenience of the experimental conditions.

• 한국농공학회논문집
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• 제50권1호
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• pp.95-106
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• 2008

Eco-friendly material and implementation methods have become important along with the existing standardized maintenance concept for the irrigation and flood control. However, the intrinsic function of the hydraulic structure is water supply and disaster prevention. Therefore, the material and work methods should be considered both eco-friendliness, durability and safety which are prerequisite elements to maintain the engineering function. In this study eco-friendly material and work methods would be classified into the vegetation based system, eco-friendly concrete system and stone-material system according to the characteristics of material. The quality standard for durability followed KS specification and related regulations. The quality standard for safety and eco-friendliness was set after literature review, and the database was developed using the standard. The structure applicable to onsite - the eco-friendly material and work method were classified based on the function and material of the hydraulic structure. Finally, database has been established for convenient management and selection of the proper material and work method. The eco-friendly material and work method could be searched easily for the convenience of the users, and the web-based data system has been developed for continuous registration of the material and work methods to be developed in the future.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.108.1-108.1
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• 2011

This paper proposes the method to develop the fuel of suljigemi pellets using agricultural by-products the occurred during the manufacturing of alcohol. This paper is the goal to make sulgigemi pellet fuel for develops pellet of high calorie. The methods of sulgigemi pellet manufacturing well mix as the dough with the water and the sulgigemi. And then we have dried in the after compression and molding using well mixed the sulgigemi. The moisture of pellets has dried it removed until about 85%. Suljigemi pellet has the effect of zero emission as the soil conditioner using ash after burning. The merits for the sulgigemi pellet are the convenience of storage and custody. Also sulgigemi pellet has the reduction effect of carriage fee, fuel economy and low-cost high-efficiency effects, environmentally clean fuel as CO2 emissions savings. In experiment, we confirmed to calories of the wood pellet and the sulgigemi pellet. The calorie of the suljigemi pellets has high 233 kilo calories than the wood pellets. So the technologies of the sulgigemi fuel pellets are developing low carbon, green growth renewable energy fuel through futuristic energy system will be.