• 한국분무공학회지
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• 제28권4호
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• pp.176-183
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• 2023

Many countries are striving to reduce carbon emissions with the goal of net zero by 2050. Accordingly, vehicles are rapidly being electrified to reduce greenhouse gases in the transportation sector. However, many organizations predict that internal combustion engines of LDV (light-duty vehicle) will exist even in 2050, and it is difficult to electrify aircraft and large ships in a short time. Therefore, synthetic fuel (i.e., e-Fuel) that can reduce carbon emissions and replace existing fossil fuels is in the spotlight. The e-Fuel refers to a fuel synthesized by using carbon obtained through various carbon capture technologies and green hydrogen produced by eco-friendly renewable energy. The purpose of this study is to compare and analyze the injection and spray characteristics of the simulated e-Gasoline. We mixed the hydrocarbon fuel components according to the composition ratio of the synthetic fuel produced based on the FT(Fischer-Tropsch) process. As a result of injection rate measurement, simulated e-Gasoline showed no significant difference in injection delay and injection period compared to standard gasoline. However, due to the low vapor pressure of the simulated e-Gasoline, the spray tip penetration (STP) was lower, and the size of spray droplets was larger than that of traditional gasoline.

• 무역상무연구
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• 제46권
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• pp.265-313
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• 2010

Kyoto Protocol is an international convention on concrete performance program for UNFCCC(United Nations Framework Convention on Climate Change), which regulate and prevent to global warming and officially came into effect on February 16, 2005. Kyoto flexible mechanisms, the agreed environmental system in March 1997 in the Third Conference of Parties in UNFCCC General Assembly, Emission Trading System(ETS), Clean Development Mechanism(CDM) and Joint Implementation(JI), are key policies related to environment. In advanced countries, greenhouse gas emissions should be reduced average 5.2% level compared to 1990 in total emissions during 2008-2012. World leading carbon market finished the trial on the EU ETS I greenhouse gas emissions trading system, EU ETS II is operated regularly after 2008. World Bank leads to make 'Prototype Carbon Fund(PCF)' in April 2004, which is the world first carbon fund and a representative public carbon fund type, World Bank operate various funds including present PCF. Thus, I would like to propose as follows in relation to this study: First, in the validity analysis of carbon funds, it would be needed to analyze the Emission Reduction Cost Efficiency(ERCE) of carbon. The ERCE is a break-even value which brings the Net Present Value(NPV) to zero. NPV approach is used among projects and it enables potential projects to be compared and evaluated the ERCE on the basis of the net present value of net future cash flows. Therefore, according to results of analysis, carbon funds should be developed and invested. Second, it would be necessary to allow of issuing bonds together with carbon funds, carbon finance etc. Third, carbon funds, it would be reasonable to have a relatively enough maturity in project and as a financial derivatives in the international financial markets, it is needed various types of transactions. Fourth, it would be needed to standardize the carbon emissions trading for more efficiently. Fifth, it would be necessary to establish and invest in various kinds of domestic and overseas global carbon funds, including governments, privates, governments and privates sectors. And it is also needed to establish the medium and long term plans for carbon funds. Sixth, it would be needed to foster the advanced trade mechanisms for carbon funds in the most effective ways. Finally, carbon funds should be used in harmony with international societies to reduce global warming as the social responsible investing funds and it should be contribute to sustainable development. In addition, it would seem that carbon funds should be studied on establishing the contributable standard of sustainable development in the future assignment.

• 대한환경공학회지
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• 제38권9호
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• pp.521-527
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• 2016

나노 영가철은 산화환원기작을 통하여 염소계 유기화합물과 같은 물질을 효과적으로 처리할 수 있다고 알려져 있지만, 작은 사이즈로 인하여 회수가 어려운 단점으로 인하여 실제 수처리 공정에서는 유출 등의 우려로 널리 적용되지 못하였다. 이와 같은 한계를 극복하기 위하여 활성탄과 같은 담체에 고정화 하여 사용하는 연구가 활발히 진행되었다. 본 연구에서는 활성탄에 영가철의 고정화 시 대표적으로 사용되는 고온 및 상온의 두 가지 경로에 대해 평가하였으며, 결과를 바탕으로 최적의 합성 조건을 도출하였다. 효과적인 나노영가철/입상활성탄 복합체를 합성하기 위해서는 높은 철 함량과 더불어 영가철의 분율을 높이는 것이 중요하며, 이를 위해서는 합성 과정에서 형성되는 철 산화물 및 수산화물의 형성을 억제하는 것이 중요한 것으로 나타났다. 또한 영가철의 분율을 높이기 위한 환원 시간 및 중간 건조 과정의 유무 등 합성 조건의 영향을 살펴보았으며, 그 결과 중간 건조 과정 없이 바로 $NaBH_4$를 이용한 환원 조건을 약 2시간 이상 유지하는 것이 최적 조건임을 확인하였다. 합성된 나노영가철/입상활성탄 복합체는 활성탄의 흡착 능력과 영가철의 환원 능력을 동시에 보유함으로써 나이트로벤젠과 같은 환원이 가능한 오염물질의 제거에 효과적으로 나타났다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.227-230
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• 2000

Batch cultivations of Anaerobiospirillum succiniciproducens have been systematically studied for the economical production of succinic acid from wood hydrolysate with corn steep liquor(CSL) as a nitrogen source. CSL was found to be an alternative complex nitrogen source for A. succiniciproducens when glucose and wood hydrolysate were used as carbon sources. Compared with polypeptone and/or yeast extract, CSL had similar effects on fermentation performance such as succinic acid yield and a ratio of succinic acid to acetic acid in the fermentation of wood hydrolysate as well as glucose. This means that succinic acid can be produced more economically from wood hydrolysate and CSL than relatively expensive carbon and nitrogen sources. Besides its low cost, the alternative medium served as a green technology for succinic acid production because it gives a net-zero effect on global warming.

• 대한기계학회논문집
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• 제6권2호
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• pp.101-106
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• 1982

This study was undertaken to determine tensile properties and low-cycle fatigue behavior of 0.6%C high carbon steel used of structural purposes at temperatures up to 500.deg.C. In the low-cycle fatigue test the upper limit was decided by elongation(i.e. the total strain range), while the lower limit was defined by the load (i.e. zero load). The following results were obtained. Both, the ultimate tensile strength and low-cycle fatigue resistance attain the maximum values near 250.deg.C. Above this temperature the values decrease rapidly as the temperature increases. The low-cycle fatigue resistance decreases whenever there is an increase of the total strain range. Because the hardness of cycle fatigued specimen correlates cyclic hardening and cyclic softening, therefore the hardness of cycle fatigued specimen is smaller than that of the nonfatigued specimen at room temperature and 500.deg.C but much larger than the hardness of the nonfatigued specimen near 250.deg.C.

• 한국안전학회지
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• 제7권4호
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• pp.45-53
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• 1992

Sponataneous ignition characteristics for granulated activated carbon were observed by performing experiments at constant ambient temperature and varying the ambient temperature sinusoidally. In case of varying the ambient temperature sinusoidally, the amplitudes of temperature were 5$^{\circ}C$, 1$0^{\circ}C$ and 15$^{\circ}C$ respectively, and the period in each amplitude was varied at an interval of 30minutes from zero to 3hours. As the results of experiments at a constant ambient temperature, the critical spontaneous ignition temperature of the sample decreased as the sample vessel size increased. Apparent activation energy of the sample calculated from the Frank-Kamenetskii's thermal Ignition theory was 38.82［kca1/mo1］ In case of varying the ambient temperature sinusoidally, the critical spontaneous ignition tempera-ture was lower than that at the constant ambient temperature, and the minimum critical spontaneous ignition temperature decreased with the amplitude of heating sinusoidal curve. At the same amplitude, the critical spontaneous ignition temperature decreased until it reached the minimum point and then in-creased as the period increased.

• Journal of Advanced Marine Engineering and Technology
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• 제18권3호
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• pp.10-16
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• 1994

This study aimed at measuring the latent heat of phase transformation of S45C carbon steel in quenching and at conducting the analytical researches into the calculation of cooling curves including the latent heat. The temperature of phase transformation of steel and its latent heat are dependant upon the cooling rates at the temperature of A1 phase transformation point. The effect of the latent heat of phase transformation is especially manifest at the cooling curve of center of specimens. The higher the cooling rates became, the lower fell the temperature region of phase transformation. In the figures of cooling rates, the phenomena of cooling rate dropping into zero was caused by the latent heat of phase transformation.

• 자원ㆍ환경경제연구
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• 제9권3호
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• pp.489-513
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• 2000

This paper introduces a new method to estimate and decompose sources of carbon dioxide emissions using an input-output model with decomposition method free of residual usually associated with this kind of analysis. This method is different from others, using what we call 'mean rate-of-change index (MRCI)' for weights of the decomposed terms. Ang et al.(1998) asserted that logarithmic mean divisia index(LMDI) is superior to Laspeyres index(LI) or simple average divisia index(SADI) since it reduces residual to zero. We claim that our method is an improvement over the other methods because it enables residual free decomposition even when data contain negative values, the case which LMDI cannot handle. We demonstrate by way of showing some examples that our method is superior to LI, SADI(Proops, 1993 and Chung, 1998) or LMDI(Ang et al., 1998).

• 한국환경보건학회지
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• 제27권2호
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• pp.43-50
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• 2001

This paper reviews the results of a series of efforts to develop structure-activity models for slow-reacting chemicals and olefins whose toxicity may be enhanced by the ultraviolet radiation. Photoinduced toxicity of 14 compounds was found to be a different result of competing factors of structure, having carbon-carbon double bonds. To mimic the biological consequences of photooxidative damage in mammalian cells, the photochemical mutagenicith of 14 chemicals was tested in the CAS. Simple olefins were photochemically mutagenic or carcinogenic with irradiation, increasing the alkylating activity from zero level to 0.87(abs/gram) for styrene, 0.25 for 1-butene, 0.11 for 1-hexene, respectively, whereas no photochemical mutagenicity was observed with 1-octene in the absence of the CAS. Oxide compounds, however, showed a decreasing trend of photoalkylating activities in the presence or absence of the CAS. We found that the structure-activity relationship was not applicable to our data.

• 수산해양기술연구
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• 제27권4호
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• pp.321-327
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• 1991

Experiments of quenching were made with cylindrical specimens of carbon steel S45C of diameters from 12 to 30mm were performed. The specimens were heated by electric furnace and quenched by immersion method. In order to analyze the temperature profile(cooling curves) of carbon steel including the latent heat of phase transformation, nonlinear heat conduction problem was calculated by the numerical method of inverse heat conduction problem using the apparent heat capacity method. The difference between the calculated and the experimented cooling curves was caused by the latent heat of phase transformation, and the effects of the latent heat were especially manifest at the cooling curves of center of specimens. The temperature and the quantity of the latent heat of phase transformation depend on the cooling speed at A sub(1) transformation point, and the region for cooling speed to become zero was caused by the latent heat of phase transformation.