• 제목/요약/키워드: thermal processing

검색결과 1,443건 처리시간 0.03초

Simulation Study on Measuring Pulverized Coal Concentration in Power Plant Boiler

  • Chen, Lijun;Wang, Yang;Su, Cheng
    • Journal of Information Processing Systems
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    • 제15권1호
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    • pp.189-202
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    • 2019
  • During thermal power coal-fired boiler operation, it is very important to detect the pulverized coal concentration in the air pipeline for the boiler combustion stability and economic security. Because the current measurement methods used by power plants are often involved with large measurement errors and unable to monitor the pulverized coal concentration in real-time, a new method is needed. In this paper, a new method based on microwave circular waveguide is presented. High Frequency Electromagnetic Simulation (HFSS) software was used to construct a simulation model for measuring pulverized coal concentration in power plant pipeline. Theoretical analysis and simulation experiments were done to find the effective microwave emission frequency, installation angle, the type of antenna probe, antenna installation distance and other important parameters. Finally, field experiment in Jilin Thermal Power Plant proved that with selected parameters, the measuring device accurately reflected the changes in the concentration of pulverized coal.

Periodic Mapping을 통한 프로세서 레지스터 파일의 온도 관리 (Periodic Mapping : Thermal Management for Processor Register File)

  • 허인구;박상현;김용주;윤종희;이진용;백윤흥
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2010년도 춘계학술발표대회
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    • pp.29-32
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    • 2010
  • 공정이 미세화 될수록 프로세서 상에서의 thermal management는 점점 중요해지고 있다. 칩의 온도가 임계 온도를 넘어 손상되거나, 시스템이 불능이 되는 상황을 방지하기 위해 그 동안 많은 기법들이 소개되어 왔다. 하지만 이러한 기법들은 시스템 전체를 끄거나 느려지게 함으로써 상당한 양의 성능 저하를 가져왔다. 이 논문에서는 프로세서의 가장 중요한 Hotspot인 Register File의 온도 관리를 위한 기법으로 Periodic Mapping을 제안하고, 이를 기존의 기법들과 비교해 본다.

Enhanced salt coating on FeS2 surface with the addition of Li2O

  • Cheong, Hae-Won;Kang, Seung-Ho;Kim, Jong-Myong;Cho, Sung-Baek
    • Journal of Ceramic Processing Research
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    • 제13권spc2호
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    • pp.198-201
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    • 2012
  • The electrolytes in thermal batteries are nonconductive solids at ambient temperature, which prevent the self-discharge and corrosion. To meet severe environmental requirements and guarantee acceptable handling yields, all the pellets in cells should have adequate strength, especially for the cathodes due to their poor binding properties among FeS2 particles. By modifying the surface microstructure of FeS2 through molten-salt heat treatment, the inter-particle binding strength is greatly increased, resulting in the enhanced pellet strength and yield. The addition of Li2O also promoted the soft salt coating coverage of hard FeS2 particles, which can be explained by the enhanced wettability of the molten salt.

우유의 가열 및 비가열 살균 기술에 관한 연구 동향 (Impact of Thermal and Nonthermal Technologies in Milk Processing)

  • 박중근;이여진;윤준용;엄애선
    • Journal of Dairy Science and Biotechnology
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    • 제33권3호
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    • pp.223-229
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    • 2015
  • Milk is a food with high nutritional value as it contains abundant water, proteins, vitamins, lactose, fat, minerals, enzymes, etc. However, in order to make milk suitable for intake, it should be thermally treated to eliminate microbiologically hazardous factors. Heat treatment is an essential sanitation process for milk, but various precautions must be taken in order to process and preserve it. Therefore, various techniques should be developed to minimize the nutrient loss and to ensure that milk is safe for consumption, conservation, and distribution. However, the existing thermal pasteurization methods are harmful and increase the nutrient loss; moreover, no new thermal pasteurization methods are being researched that are safe for the human health and minimize the nutrient loss. Hence, this study aims to review new processes for thermal (low temperatures) and no thermal pasteurization methods that can minimize the nutrient loss during milk pasteurization.

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금속용사 방식공법의 경제성 평가에 관한 연구 (A Study on the Economic Evaluation of Thermal Spray Methods for the Corrosion Protection of Steel)

  • 정성호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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    • pp.13-16
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    • 2005
  • Generally, as corrosive protection processing of a steel structure, zinc galvanizing and heavy duty coating paint are applied. However, zinc galvanizing has the difficulty of restriction of a size, or on-site construction. Moreover, heavy duty coating paint has a problem with many administrative and maintenance expenses with short problem of adhesion, corrosion generating of a damage portion, and maintenance management cycle. In this study, a salt water spray test, CASS test, and the electrochemistry examination were carried out for the thermal metal spray method of construction for corrosive protection performance evaluation. Moreover, the corrosive protection life of a thermal metal spray method of construction was quantitatively calculated on the basis of this experiment. in consideration of LCC, the economical efficiency of a general corrosive protection method of construction and a thermal metal corrosive protection method of construction was compared. Consequently, although initial construction expense was estimated 16 to $30\%$ high, as for a thermal metal spray method of construction, it turns out that the administrative and maintenance expenses for 100 years became cheap 9.3 to 13 or more times.

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사각판재 보론강을 사용한 유체냉각공정에서의 열변형 해석 (Thermal Deformation Simulation of Boron Steel Square Sheet in Fluid Cooling Process)

  • 서창희;권태하;전효원;오상균;박춘달;최현열;문원식
    • 소성∙가공
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    • 제26권1호
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    • pp.5-10
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    • 2017
  • Fluid cooling is one of the manufacturing processes used to control mechanical properties, and is recently used for hot stamping of automobile parts. The formed part at room temperature is heated and then cooled rapidly using various fluids in order to obtain better mechanical properties. The formed part may undergo excessive thermal deformation during rapid cooling. In order to predict the thermal deformation during fluid cooling, a coupled simulation of different fields is needed. In this study, cooling simulation of boron steel square sheet was performed. Material properties for the simulation were calculated from JMatPro, and three convection heat transfer coefficients such as water, oil and air were obtained from the experiments. It was found that the thermal deformation increased when the difference of cooling rate of sheet face increased, and the thermal deformation increased when the thickness of sheet decreased.

염료감응형 태양전지 광전극의 초음파 열처리를 통한 광전효율 개선에 관한 연구 (A Study of Photo-electric Efficiency Improvement using Ultrasonic and Thermal Treatment on Photo-electrode of DSC)

  • 김희제;김용철;최진영;김호성;이동길;홍지태
    • 전기학회논문지
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    • 제57권5호
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    • pp.803-807
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    • 2008
  • A making process of DSC(dye sensitized solar cell) was presented. In general, Photo electrodes of DSC was made by using colloid paste of nano $TiO_2$ and processing of Doctor-blade printing and high temperature sintering for porous structure. These methods lead to cracks on $TiO_2$ surface and ununiform of $TiO_2$ thickness. This phenomenon is one factor that makes low efficiency to cells. After $TiO_2$ printing on TCO glass, a physical vibration was adapted for reducing ununiform of $TiO_2$ thickness. And a thermal treatment at low temperature(under $75^{\circ}C$) was adapted for reducing cracks on $TiO_2$ surface. In this paper, we have designed and manufactured an ultrasonic circuit (100W, frequency and duty variable) and a thermal equipment. Then, we have optimized forcing time, frequency and duty of ultrasonic irradiation and thermal heating for surface treatment of photo-electrode of DSC. In I-V characteristic test of DSC, ultrasonic and thermal treated DSC shows 19% improved its efficiency against monolithic DSC. And it shows stability of light-harvesting from drastically change of light irradiation test.

허스롤 목 부위 형상 변화에 따른 열응력 분포 변화 유한요소해석 (Finite Element Analysis of Thermal Stresses on a Hearth Roll Surface Depending on Changes in the Neck Shape)

  • 나두현;이영석
    • 소성∙가공
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    • 제25권3호
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    • pp.169-175
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    • 2016
  • The hearth roll, which transfers the cold-rolled strip sheet in a Continuous Annealing Line (CAL), is always subjected to changes in the surface temperature and subsequently experiences thermal stress in service. These variations lead to the generation of thermal cracks on the hearth roll surface as well local plastic deformation. We performed finite element analysis to predict the thermal stress changes on the hearth roll surface and designed the collar shape of the hearth roll to minimize these thermal stresses. Results show that the hearth roll with a collar having an obtuse angle is much more effective than a hearth roll with collar having a right angle when the tangential stress, which is one of main causes leading to surface cracks, is compared for the various conditions. It was found that the tangential stress and the temperature on the surface of hearth roll can be reduced by 51.9% and 26℃ if the shape of roll on collar is re-designed.

금속단열재 박판의 설계인자별 단열성능 영향 연구 (Studies on Insulation Effect Related with Thin-Plate Design Factors for Reflective Metal Insulation(RMI) of Nuclear Power Plant)

  • 어민훈;이성명;장계환
    • 설비공학논문집
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    • 제28권9호
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    • pp.350-354
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    • 2016
  • Although fibrous insulations are generally used with resistive insulation type, metallic insulation is proper matter to satisfy low head-loss and equipment life when considering the specific condition, especially for Nuclear power plant. Common insulation is resistance insulation with a low thermal conductivity. but RMI is made of sheet plate with low emissivity and closed air space. Thermal radiation is blocked by stainless steel with low emissivity. Thermal conductivity and thermal convection are blocked by closed air space. This study shows the changes and effects of the heat loss according to shape and method of stacking sheet plates inserted into the insulation and analyzed the most optimized way for thermal insulation performance. The result shows that using sheet plate structure through raised and protruding shape processing was the appropriate model to optimize thermal performance. Additionally, insulating performance of RMI improved by placing the sheet plate in a high temperature region intensively.

Thermal Inactivation of Myrosinase from White Mustard Seeds

  • Ko, Young Hwan;Lee, Ran
    • 한국식품영양학회지
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    • 제34권1호
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    • pp.26-35
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    • 2021
  • Myrosinases (thioglucosidases) catalyze the hydrolysis of a class of compounds called glucosinolates, of which the aglycones show various biological functions. It is often necessary to minimize the loss of myrosinase activity during thermal processing of cruciferous vegetables. Myrosinase was isolated from a popular spice, white mustard (Sinapis alba), and its thermal inactivation kinetics was investigated. The enzyme was extracted from white mustard seeds and purified by a sequential processes of ammonium sulfate fractionation, Concanavalin A-Sepharose column chromatography, and gel permeation chromatography. At least three isozymes were revealed by Concanavalin A-Sepharose column chromatography. The purity of the major myrosinase was examined by native polyacrylamide gel electrophoresis and on-gel activity staining with methyl red. The molecular weight of the major enzyme was estimated to be 171 kDa. When the consecutive step model was used for the thermal inactivation of the major myrosinase, its inactivation energy was 44.388 kJ/mol for the early stage of destruction and 32.019 kJ/mol for the late stage of destruction. When the distinct two enzymes model was used, the inactivation energy was 77.772 kJ/mol for the labile enzyme and 95.145 kJ/mol for the stable enzyme. The thermal inactivation energies lie within energy range causing nutrient destruction on heating.