• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1237-1242
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• 2008

A study on waste heat utilization of melted slags at pyorlysis, gasification and melting system was performed. Researchers studied heat balance of substances that flow and flow out to the system which is consisted of melting furnace, combustion chamber, and waste heat boiler, then they calculated melting slags' quantity of heat by the first law of thermodynamics. If they use water cursh pit outflow which is gotten by quenching of melting slag as a energy for heating and cooling system, steam of waste heat boiler would be delivered to a steam turbine, making energy, then they will get 67,671,000 won of profit a year. It will take 3 years to repossess the cost that they invested for building it. And, if we predict durability of trash burner is 20 years, we will get approximately 1,150,407,000 won of profits in 17 years without the period when we repossess the building costs.

• 한국생산제조학회지
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• 제18권6호
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• pp.585-589
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• 2009

Extruder is divided to greatly three part at extrusion process. First, by hopper(Hopper) second, barrel(Barrel) with Screw that is point of extruder and third that is raw material supply wealth extrusion into dies(DIES) Part that decide shape of do product greatly divide. Hopper is role that distribute in raw material supply wealth (Feeding zone) of Screw preserving raw material in state of high quality how at extrusion process, and make distributed raw material as Screw in barrel rotates and 3 stage and inflicting heat and pressure raw material melting(Melting) state. And raw material of melting state Screw's measuring stoker(Metering zone) whereabouts anaphora do and product is completed through pipe channel of dies. Dies that is the most important as Screw in extrusion is part that is last part of melting state process of raw material and causes huge effect in quality of product. If more than design of dies happens, manufacture itself of dies is hard, but there are a lot of amount of losses accordingly. In this research, make pipe channel that raw material of melting state flows in dies can present dies basic design method through flow analysis of ideal pipe channel using CFdesign.

• 자연과학논문집
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• 제10권1호
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• pp.1-7
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• 1998

대정준 몬테카를로 시늉을 집중적으로 수행하여 무결정 연속고체 표면 위에 흡착된 Lennard-Jones 유체의 홑층에 대해 덮힘률 $\theta$ ~ 0.8에서 1.8 까지를 연구하였다. 시늉 결과는 최근 흑연위의 알곤 홑층 녹기에 대한 열역학적 실험측정에서 관찰되어졌던 두 단계의 녹음 행태를 뚜렷이 보여 주었다. 본 연구에서 관찰된 녹음 행태는 갑작스러운 밀도 변화 후에 점진적인 상전이로 이루어진다. 홑층 구조에 대한 스냅 사진들은 녹기과정에 어긋나기 짝의 형성과 그 짝의 분리가 연루되어 있다는 것을 가르키고 있다. 계의 크기에 의한 효과를 감안하여, 갑작스러운 밀도 변화는 Kosterlitz, Thouless, Halperin, Nelson, and Young (KTHNY)의 이론과 무관할 것인 반면에, 두 번째의 점진적 전이는 KTHNY 타입의 녹기 상전이일 것이라고 사료된다.

• 소성∙가공
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• 제23권5호
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• pp.303-310
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• 2014

Functionally graded properties are characterized by the gradual variation in composition and structure through the volume of the material, resulting in corresponding gradation in properties of the material. Direct laser melting (DLM) is a prototyping process whereby a 3-D part is built layer-wise by melting metal powder with laser scanning. Studies have been performed on the functionally graded properties induced by direct laser melting of compositionally selected metallic powders. For the current study, quadrangle structures were fabricated by DLM using Fe-Ni-Cr powders having variable compositions. Hardness and EDX analysis were conducted on cross-sections of the fabricated structure to characterize the properties. From the analysis, it is shown that functionally graded properties can be successfully obtained by DLM of selected metallic powders with varying compositions.

• 열처리공학회지
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• 제35권1호
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• pp.1-7
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• 2022

In this study, dissolution and melting phenomenon of the Al₂Cu was studied for the high-strength Al-Si-Cu aluminum alloy in automobile component. The Solution heat treatment was performed at 480℃ and 510℃ for 4hours. Microstructure analysis of the specimen was performed using the optical micrograph and scanning electron microscope for qualitative and quantitative analysis of various phases, the chemical composition of secondary phases was achieved by energy dispersive spectroscopy (EDS) and electron probe micro analysis (EPMA). As a result of the electron probe micro analysis, a plate like Al₂Cu phase was observed, and eutectic Si phase was observed of a coarsen plate shape. At a temperature of 510, necking phenomenon occurs in a specific part of plate like Al₂Cu, and it is segmented and dissolved in the Al matrix. When the temperature of the alloy exceeds the melting point of Al₂Cu, incipient melting occurs at the grain boundary of undissolved Cu particles

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.11.2-11.2
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• 2005

• 한국재료학회:학술대회논문집
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• 한국재료학회 1992년도 춘계학술발표회
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• pp.50-50
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• 1992

• 대한기계학회논문집B
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• 제38권8호
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• pp.695-700
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• 2014

본 논문에서는 수정된 증발법을 이용하여 제작된 주석(Sn) 나노입자의 녹는점 강하 특성에 대한 연구를 진행하였다. 이를 위해 대량생산이 가능한 수정된 증발법을 이용하여 10nm 급 주석 나노입자를 제조하였다. 주석 나노입자 표면의 산화 방지를 위하여 Benzyl Alcohol 을 기본유체로 사용하였으며, 제작된 주석 나노입자의 형상과 입자크기를 알아보기 위하여 투과전자현미경(TEM)을 사용하였다. 제작된 나노입자의 녹는점은 시차주사열량계(DSC)를 통해 측정하였으며, 광전자분광분석기(XPS)를 사용하여 제작된 주석 나노입자의 성분 분석을 진행 하였다. 주석 나노입자의 녹는점은 주석의 녹는점인 $232^{\circ}C$보다 44% 감소한 $129^{\circ}C$로 측정되었다. 녹는점 측정 결과는 Gibbs-Thomson 식 및 Lai 의 식과 비교하였으며, 그 결과 Lai의 식이 실험결과를 잘 예측함을 확인할 수 있었다.

• 한국식품위생안전성학회지
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• 제26권2호
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• pp.114-119
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• 2011

본 연구에서는 신선편의 채소와 과일에서 주로 검출되는 대장균(E. coli Ol577:H7), 리스테리아(L. monocytogenes), 살모넬라(Salmonella, spp.), 형색포도상구균(S. aureus)을 검출하고 동정할 수 있는 real time PCR 방법을 melting curve 분석을 활용하여 single tube 반응으로 두 종의 식중독균을 동시 검출하는 방법을 개발하고자 하였다. 대장균의 ${\beta}$-glucuronidase (uidA), 황색포도상구균의 thermonuclease (nuc), 리스테리아의 hemolycin (hly), 살모넬라의 tetrahionate reductase (ttr) 를 특이적으로 검출할 수 있는 4종의 프라이머 세트에 대한 real-time PCR의 melting curve 분석을 통하여 황색포도상구균과 대장균 동시분석 시 $T_m$ 값이 $80.6{\pm}0.9^{\circ}C$와 $86.9{\pm}0.5^{\circ}C$, 리스테리아와 살모넬라 동시분석 시 Tm 값이 $80.4{\pm}0.6^{\circ}C$와 $88.1{\pm}0.11^{\circ}C$로 확인하였고, 그 결과 정제되어진 각 식중독균의 genomic DNA를 주형으로 한 duplex real-time PCR 방법이 uniplex real-time PCR 방법과 마찬가지로 10 genome equivalents 까지 검출할 수 있는 민감도를 나타내었다. 또한, 양배추에 네 종의 식중독균을 접종하고, 증균배양 없이 DNA를 추출하여 duplex real-time PCR 을 수행한 결과 모든 식종목균에서 $10^3$ CFU/g의 검출 한계를 나타내었다. 결과적으로 개발된 melting curve 분석을 이용한 duplex real-time PCR 방법은 식품안전 증진을 위한 시간, 노동력, 비용 절감에 있어서 유효한 방법이 될 것으로 판단된다.

• 대한금속재료학회지
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• 제46권2호
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• pp.65-68
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• 2008

Generally CCM (cold crucible melting) is not suitable for melting glass. However, in this study we described the quantitative relationship between the basic property of glass and power balance, the power absorption in the melt, the losses in the coil and the cold crucible, for melting glass in CCM. The dependence of power balance on the applied frequency and the electric conductivity has been found. Above 300 kHz, the glass (B) contained alkali ion which has the low resistance $3.0{\Omega}{\cdot}cm$ at $900^{\circ}C$ and $1.36{\Omega}{\cdot}cm$ at $1,100^{\circ}C$ was melted easily and 60% of the overall power was absorbed in the melt and 30% and 10% of the overall power was lost in the cold crucible and coil respectively. Under the same condition, the glass (A) contained non-alkali ion was not melted easily and 50% of the overall power was absorbed in the melt and 40% and 10% of the overall power was lost in the cold crucible and coil respectively. In conclusion, the small absorbed power of the overall power in melt prevented a successful melting as for glass A, and the successful melting depends on the relative size of the absorbed power in melt irrespective of the melting volume. Hence, as typical for direct induction heating method(CCM), the successful melting strongly depended on the chosen working frequency based on electric conductivity of glass, power balance and the control of the critical power which was absorbed in melt.