• 한국자동차공학회논문집
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• 제4권6호
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• pp.65-77
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• 1996

A small-sized industrial diesel engine was converted to a spark ignited engine and then adapted for fuelling with natural gas. After conversion work, general combustion characteristics of the gas engine(such as ignition delay, main and total combustion durations, and heat release characteristics) were studied as a functio of major engine operating variables such as air to fuel ratio, spark timing, and spark plug type. Some other studies on cyclic variation characteristics in IMEP, Pmax and (dp/dφ)max, and also optimum combustion phasing angle were performed.

• Water Engineering Research
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• 제1권2호
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• pp.137-146
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• 2000

A windows-based software package, named DREDGE, is developed for estimating sediment resuspension and contaminant release during dredging operations. DREDGE allows user to enter the necessary dredge information, site characteristics, operational data, and contaminant characteristics, then calculates an array of concentration using the given values. The program mainly consists of the near-field models, which are obtained empirically, for estimating sediment resuspension and the far-field models, which are obtained analytically, for suspended sediment transport. A linear equilibrium partitioning approach is applied to estimate particulate and dissolved contaminant concentrations. This software package which requires only a minimal amount of data consists of three components; user input, tabular output, and graphical output. Combining the near-field and far-field models into a user-friendly windows-based computer program can greatly save dredge operator's, planners', and regulators' efforts for estimating sediment transports and contaminant distribution.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.3-6
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• 2008

Heat release characteristics of live fire load are an important parameter for performance oriented fire safety design of a building. While investigations have been carried out on the fire load and its burning behavior in office, residential and commercial buildings and so on, little effort has been paid for the rational treatment of fire load in bookstore. In this report, burning behavior of typical combustible objects in bookstore are studied by measuring heat release rates of bookshelf with book.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.1061-1063
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• 2002

In this paper, the characteristics of the pyro unit applied to rocket release device in KSR-Ill are analyzed by experimental results, which are the current and voltage waveforms of the battery used as energy source. The precision design approach of the rocket release device can be achieved since the behavior and the required energy of the pyro are identified through the results.

• Journal of Pharmaceutical Investigation
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• 제21권1호
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• pp.51-55
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• 1991

Porous spheres composed of natural waxes and inorganic materials containing vitamin E acetate as a drug were prepared by impregnation method. Furthermore, the amount of vitamin E acetate entrapped in the spheres and the release rate of vitamin E acetate from the spheres were studied. The impregnation of vitamin E acetate was carried out by dipping the spheres in vitamin E acetate solutions. Entrapment mechanism of vitamin E acetate could be expressed in terms of Langmuir's adsorption isotherm. The amount of vitamin E acetate entrapped in porous spheres was influenced by the structure and concentration of the polymer used in vitamin E acetate solutions, and the concentration of vitamin E acetate. Release characteristics of vitamin E acetate from the spheres were investigated by withdrawing samples periodically and analyzing them by spectrophotomer.

• 태양에너지
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• 제9권2호
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• pp.22-30
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• 1989

Since the energy storage method by means of the thermochemical reaction has no heat loss by separating the reactants under the storage period, it is remarked as one of promising means particularly for long-term heat storage. In this study, the heat-storage/-release characteristics of the reversible chemical reaction cycle, $Ca(OH)_2/CaO$, is numerically analysed by a mathematical modelling. As a result, the effectiveness of the heat exchanger by the chemical heat storage method is considerably higher than that by the sensible heat storage method. It is found that the major parameters, which determines the effectiveness of the heat exchanger, are the mass flow rate and inlet temperature of fluid, the residence time, etc.. The heat-storage/-release period can be controlled by changing the operation conditions. It is expected that the results obtained here will supply useful informations in designing a regenerative heat exchanger utilizing the thermochemical reaction.

• Archives of Pharmacal Research
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• 제5권2호
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• pp.61-70
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• 1982

Sulfisoxazole, a chemotherapeutic agent, was microencapsulated with ethylcellulose by means of phase separation form cyclohexane by temperatture change. The size distribution was determined by use of standard sieves and the effect of core to wall ratio was noted. To examine their shapes and usrface characteristics, the microcapsules were observed with a scanning electron microscope. Release of the drug from microcapsules into pH 7.5 buffer medium was studied. The release pattern was found to have similar properties to the release of a drug from an insoluble porous matrix reported. The apparent diffusion coefficient of sulfisoxazole was measured for the transport of the drug from the core of microcapsules into the surronding sink condition. The apparent diffusion coefficient increased with increasing capsule size.

• 한국화재소방학회논문지
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• 제17권2호
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• pp.17-24
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• 2003

본 논문은 파스콘 또는 콘크리트 재질의 트로프에 설치되는 전선에 대한 열의 영향과 이들 트로프에 대한 열 방출 정도에 대한 차이점을 이론상으로 접근하고 평가하고자 하였으며, 실제 상황과 근접한 조건으로 컴퓨터 시뮬레이션을 실시함으로서 두 트로프 내의 전선에 대한 열의 영향과 두 트로프의 열 발산정도를 추정하고 그에 대한 타당성을 입증하고자 하였다. 이에 대한 연구 결과 파스콘의 고유 열전도 값과 콘크리트의 고유 열전도 값을 단순 비교하면 콘크리트 제품의 열 방출량이 우수한 것으로 판단할 수 있으나, 실제 설치되는 두 트로프의 실제 두께와 면적 및 세부 구조를 고려하여 연산 및 시뮬레이션을 실시해 본 결과 파스콘 트로프가 콘크리트 트로프 보다 다소 우위에 있는 것으로 평가되었다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.41-42
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• 2006

A study on the combustion characteristics by using Emulsion Fuel in Diesel Engine is performed experimentally. In this paper, the experiments are performed at engine speed 1800rpm, emulsion fuel ratio is 0%, 10%, 20%, and main measured items are specific fuel consumption, pressure, ratio of pressure rise, rate of heat release etc. The obtained conclusions are as follows. 1) Specific fuel consumption increase maximum 19.8% at low load, but is not effected at full load. 2) Ratio of pressure rise and rate of heat release are about the same in the case of 10% and 20% of emulsion fuel ratio. 3) Cylinder Pressure increase 11.7%, ratio of pressure rise increase 60.4% in case of emulsion fuel ratio 20% at full load. 4) Rate of heat release increase 76.9% in case of emulsion fuel ratio 20% at full load.

• Journal of Advanced Marine Engineering and Technology
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• 제28권4호
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• pp.618-623
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• 2004

This paper has dealt with the heat storage characteristics of gel type micro size latent heat storage material slurry. The heat release operation to the gel type micro size latent heat storage material slurry was carried out using hot air bubbles by direct contact heat exchange. This experiment was carried out using phase change material of n-paraffin so the heat release amount is higher than cold water system. The parameters of this experiment were concentration of latent heat phase change material, height of heat release bath and inlet velocity of hot air. The main results obtained are as follows : (1) The effect of concentration of latent heat phase change material dispersed with water is very affective to the direct contact heat exchange between hot air and gel type micro size latent heat storage material slurry. (2) It is clarified that the most effective concentration of latent heat phase change material dispersed with water exists around 20mass% at this type of direct heat exchange model experiment.