• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1974-1976
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• 2005

The feasibility of a midgap metal gate is investigated for 32nm MOSFET low power applications. The midgap metal gate MOSFET is found to deliver a driving current as high as a bandedge gate one for the low power applications if a proper retrograde channel is used. An adequate design of the retrograde channel is essential to achieve the performance requirement given in ITRS roadmap. In addition, a process simulation is run using halo implants and thermal processes to evaluate the feasibility of the necessary retrograde profile in manufacturing environments. From the thermal budget point of view, the bandedge metal gate MOSFET is more vulnerable to the following thermal process than the midgap metal gate MOSFET since it requires a steeper retrograde doping profile. Based on the results, a guideline for the gate workfunction and the channel profile in the 32 nm MOSFET is proposed.

• 한국주조공학회지
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• 제7권2호
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• pp.122-132
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• 1987

Full mold casting process is a new technique offering numerous advantages and promising possibilities. The present study is aimed to bring out the results of experiments carried out to study the effect of pattern coatings on the solidification of 99.5% pure aluminum plate-shaped castings in the various sand molds and the thermal behavior of the molds. The results of the investigation indicate that (i) with increase in pattern coating thickness, the relative chilling power decreases gradually for silica and increases for zircon coating, and (ii) the application of a pattern coating significantly reduces the maximum interface temperature by the mold which is more pronounced in the case of thinner mold wall. The investigation also indicates that Chvorinov's rule is not found to be valid for the casting in the full mold, with or without pattern coating. Therefore in full mold process, the pattern coating thickness will be a very important parameter in the study of thermal behavior.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 금형가공,미세가공,플라스틱가공 공동 심포지엄
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• pp.9-12
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• 2005

The rapid thermal response (RTR) molding is a novel process developed to raise the temperature of mold surface rapidly to the polymer melt temperature prior to the injection stage and then cool rapidly to the ejection temperature. The resulting filling process is achieved inside a hot mold cavity by prohibiting formation of frozen layer so as to enable thin wall injection molding without filing difficulty. The present work covers flow simulation of thin wall injection molding using the RTR molding process. In order to take into account the effects of thermal boundary conditions of the RTR mold, coupled analysis with transient heat transfer simulation is suggested and compared with conventional isothermal analysis. The proposed coupled simulation approach based on solid elements provides reliable thin wall flow estimation fur both the conventional molding and the RTR molding processes

• 산업식품공학
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• 제21권4호
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• pp.303-311
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• 2017

To automate cooking processes, quantitative descriptions are needed on how quality parameters, such as texture change during heating. Understanding mechanical property changes in foods during thermal treatment due to changes in chemical composition or physical structure is important in the context of engineering models and in precise control of quality in general. Texture degradation of food materials has been studied widely and softening kinetic parameters have been reported in many studies. For a better understanding of kinetic parameters, applied kinetic models were investigated, then rate constants at $100^{\circ}C$ and activation energy from previous kinetic studies were compared. The food materials are hardly classified into similar softening kinetics. The range of parameters is wide regardless of food types due to the complexity of food material, different testing methods, sample size, and geometry. Kinetic parameters are essential for optimal process design. For broad and reliable applications, kinetic parameters should be generated by a more consistent manner so that those of foods could be compared or grouped.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.1731-1735
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• 2021

The operation of the nuclear reactor requires accurate and fast methods and techniques for analysing its kinetics. These techniques become even more important when the MOX-fuel is used due to the lower value of delayed neutron fraction 𝛽 for ²³⁹Pu. Based on a Birth-and-Death process review, the mathematical model of thermal reactor core has been proposed different from existing ones. The analytical method for thermal point-reactor parameters evaluation is described within this work. The proposed method is applied for analysis of the unsteady transient processes taking place in a thermal reactor at its start-up or shutdown power change, as well as during small accidental power variation from the rated value. Theoretical determination of MASURCA reactor core reactivity through the analysis of experimental data on neutron time spectra was made.

• ETRI Journal
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• 제25권2호
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• pp.73-80
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• 2003

This paper describes an effective method for forming silicon oxide on silica-on-silicon platforms, which results in excellent characteristics for hybrid integration. Among the many processes involved in fabricating silica-on-silicon platforms with planar lightwave circuits (PLCs), the process for forming silicon oxide on an etched silicon substrate is very important for obtaining transparent silica film because it determines the compatibility at the interface between the silicon and the silica film. To investigate the effects of the formation process of the silicon oxide on the characteristics of the silica PLC platform, we compared two silicon oxide formation processes: thermal oxidation and plasma-enhanced chemical vapor deposition (PECVD). Thermal oxidation in fabricating silica platforms generates defects and a cristobalite crystal phase, which results in deterioration of the optical waveguide characteristics. On the other hand, a silica platform with the silicon oxide layer deposited by PECVD has a transparent planar optical waveguide because the crystal growth of the silica has been suppressed. We confirm that the PECVD method is an effective process for silicon oxide formation for a silica platform with excellent characteristics.

• 태양에너지
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• 제19권2호
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• pp.57-65
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• 1999

[ $H_2O$ ]-NaCl혼합물을 냉축열재로 선택하였으며, 이 혼합물의 상변화온도를 몰농도 변화에 의하여 조절하였다. 그리고 고농도와 저농도의 NaCl과 $H_2O$가 ion-dipole interaction으로 결합하는 구조를 그림으로 가시화하고 가열, 냉각과정에서 $H_2O$-NaCl이 동결, 융해하는 현상을 도시하므로서 융해와 동결과정에서 상변화온도가 2단계로 나타나는 구조적 원인을 구명하였으며, NaCl의 농도변화에 따른 상변화온도를 이론적으로 분석하므로서 실험 및 이론분석 결과의 타당성을 증명할 수 있도록 하였다.

• KIEAE Journal
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• 제12권3호
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• pp.95-100
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• 2012

Thermal phenomena has caused abnormal weather phenomena due to the lack of urban green spaces To solve these problems, the country of recorded a city business is actively evolving trends. but in all the land, most built-up city's green buildings unless the demolition of the composition is an impossible situation, green space in urban areas, with emphasis on composition. In this study, thermal power plants that occured in the evolution of vegetation by utilizing Bottom Ash was tried to develop a lightweight block. Bottom Ash block to take advantage of vegetation is focused create green space in urban areas Vegetation in the block was carried out manufacturing lightweight, porous, lightweight water ratio suitable for three types of blocks selected according to its kind study on the manufacturing and process. Bottom Ash from this study at the time of disposal of coal ash generated by recycling the landfill shortages, loss of landfill costs, environmental pollution and are trying to solve the same problem at the same time.

• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.15-22
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• 1999

일반적으로 빌드업 다층 인쇄회로기판은 에칭, 도금등의 습식공정에 의해 제작이 이루어지므로 많은 장비와 많은 시간이 필요하게 된다. 이러한 습식공정은 양산에는 적합하지만 개발단계에서는 그리 적합하지 않은 방법이다. 본 연구에서는 스크린 인쇄기술을 도입하여 빌드업 다층 인쇄회로기판을 제작하여 보았다. 절연성 재료로는 광경화성수지 또는 열경화성수지를 사용하였으며 전도성 재료로는 전도성 페이스트를 사용하였다. 층간의 전기적 연결을 담당하는 비아와 회로를 형성하기 위해 스크린 인쇄공정을 통해 전도성 페이스트를 인쇄 하였다. 이러한 방법을 통해 제품의 개발 단계에서 기존의 빌드업 다층 인쇄회로기판 제작 공정과 비교하여 좀더 효율적인 방법을 제시하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.169-172
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• 2004

The effect of the process parameters on the stable lifetime in rapid thermal firing(RTF) was investigated in order to optimize the process for the Cz-silicon. The process temperature was varied between $700^{\circ}C\;and\;950^{\circ}C$ while the process time was chosen 1 s and 10 s. At below $850^{\circ}C$ the stable lifetime for 10 s is higher than that for 1 s and increases with increasing by the process temperature. However, at over $850^{\circ}C$ the improved stable lifetime is not dependent on the process time and temperature. On the other hand, two high temperature processes in solar cell fabrics are combined with the optimized process and the non-optimized process. The last process determines the stable lifetime. Also, the degraded stable lifetime could be increased by processing in optimized process. The decreased lifetime can increase using the optimized oxidation process, which is a final process in solar cells. Finally, the optimized and non-optimized processes are applied solar cells.