• Title/Summary/Keyword: 가열선

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A Mechanics-Based Determination of Heating Lines in Line Heating Process (열변형 해석 기구를 통한 선상 가열에서의 가열선 수정에 관한 연구)

  • Yong-Gyun Kim;Jong-Gye Shin
    • Journal of the Society of Naval Architects of Korea
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    • v.39 no.2
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    • pp.45-51
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    • 2002
  • In Line Heating method, heating line is determined by kinematics analysis. But the heating line, which is solved by kinematics analysis, doesn't verify by the point of physical analysis and the choice problem in many heating line doesn't determine. In this paper, the simulator is developed. When we get the processing information at the kinematics analysis, simulator can estimate the shape of deformed plate that process along the processing information. When we get the initial shape and the object shape, we calculate the processing information first, using kinematics analysis. In a simulator, we estimate deformed shape from the processing information. After this we compare deformed shape and object shape. If the error of deformed shape and object shape is in the proper limits, that information is determined the final processing information. Else we repeat the process changing variables.

Optimal Positioning of Heating Lines in a Compression Molding Die Using the Boundary Element Method (경계요소법을 이용한 압축성형다이 가열선의 최적위치 설계)

  • 이부윤;조종래
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.6
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    • pp.1478-1485
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    • 1993
  • A shape optimization problem is formulated to determine the optimal position of heating lines in a compression molding die. The objective of the problem is that the cavity surface would be maintained by a prescribed uniform temperature. A boundary integral equation for the sensitivity of the temperature in terms of hole position is derived using the method of shape design sensitivity analysis. The boundary element method is employed to analyze the temperature and sensitivity field of the die. The sensitivity calculation algorithm is incorporated in an optimization routine. To demonstrate a numerical implementation, an example problem arising in thermal design of a compression molding die is dealt with, showing that the number of heating lines chosen for the die strongly affects the ultimate uniformity of the cavity surface temperature.

Heating-Plan Heuristics for Forming Curved Shell Plate of Ship Structure (선체 외판 부재의 곡 성형을 위한 가열 계획 생성 휴리스틱)

  • Gang, Byeong-Ho;Park, Gi-Yeok;Kim, Ung;Ryu, Gwang-Ryeol;Lee, Jeong-Hwan;Do, Yeong-Chil;Kim, Dae-Gyeong;Kim, Se-Hwan
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2007.11a
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    • pp.570-578
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    • 2007
  • 선체 외판 부재의 곡 성형 과정은 주로 가열(열간가공)에 의해 수행된다. 이 가열 작업은 작업자의 경험과 지식에 크게 의존하는 매우 어려운 작업이다. 본 논문에서는 선체 외판의 곡 성형을 위한 가열 계획을 자동으로 수립할 수 있는 휴리스틱을 소개한다. 현장 전문가의 지식에 기반한 이 휴리스틱은 크게 가열 선을 생성하는 부분과 외력을 주는 도구를 배치하는 부분으로 구성된다. 가열 선은 대상 부재의 현재 곡면과 설계된 목적곡면과의 비교를 통해 생성되고, 가우스 커널 함수를 통해 스무딩(smoothing)된다. 현장에서는 열간가공 시 의도하지 않은 변형을 막으면서 작업시간을 줄이고자 외력을 이용한다. 외력의 위치와 방향은 가열 선 군집화를 통해 추출된 대표 가열 선을 기준으로 결정된다. 가상의 인공 곡면과 현장의 실제 부재를 대상으로 실험한 결과, 이 휴리스틱이 숙련된 전문가가 수립한 가열 계획과 유사한 가열 계획을 수립할 수 있음을 확인하였다.

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The Effects of Warm and Cold Stimulations on the Temperature Distribution in the Prostate (냉.온열의 반복 자극이 전립선 내부의 온도 분포에 미치는 영향)

  • 문우석;백병준;박복춘;김철생
    • Journal of Biomedical Engineering Research
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    • v.23 no.6
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    • pp.467-475
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    • 2002
  • Hyperthermia using transrectal thermal probes has been used for a noninvasive treatment of prostate diseases. However it is known that heating the rectal wall at excessively high temperature can lead to destruction of the rectal mucous membrane. and it is difficult to maintain an optimum temperature over the entire prostate. Thus, a more accurate understanding of the heat transfer mechanism between prostate and hyperthermia system is needed Numerical analysis was performed to investigate how the cold/warm stimulations on the prostate surface affect the temperature distribution in the prostate model. The general purpose software "FLUENT" was used for obtaining a finite volume solution to the unsteady conduction equation and to calculate the time-varying temperature in the prostate. Effects of the warm/cold stimulations and the stimulation frequency on the temperature distribution were simulated. and we visualized how hyperthermia affected the inside of the prostate. It was found that the effect of hyperthermia by using a typical heating method is limited due to the low thermal conductivity of the prostate. Consecutive repetitions of warm and cold stimulations were considered to provide the thermal irritations inside a prostate. The effects of temperature difference and duration of warm/cold stimulations were investigated, and basic data for the optimum period and effective patterns of stimulations were obtained. A simplified bioheat equation was also solved to describe effects of the blood flow on the blood-tissue heat transfer. The effect of blood flow was not dominant compared to that of warm/cold stimulations. These results might be used as data for design of prostate treating probe, prostatic therapy and thermal stimulation effects on the prostate.

A New Algorithm to Determine Heating Lines for Plate Forming by Line Heating Method (선상가열법에 의한 강판 가공의 가열선 결정 알고리즘)

  • Chang-Doo Jang;Sung-Choon Moon
    • Journal of the Society of Naval Architects of Korea
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    • v.35 no.2
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    • pp.104-113
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    • 1998
  • The line heating method is a popular technique used to form ship hull in shipyards. In order to promote shipbuilding productivity, some researchers have made progress in their studies on automatic fabrication system for plate forming. These researches have, however, focused on heat-induced plate deformation with particular mechanical modelings, and do not yet propose the heating paths applicable to actual plate forming process. In this paper, a new algorithm to determine heating lines is developed to simulate the line heating process. The important feature of this algorithm is that it calculates principal curvatures of deflection difference surface which represents difference between target surface and surface in fabrication. Several trials to typical surface types show its usefulness and good applicability to tactical use.

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Gamma Irradiation for the Inhibition of Shrimp (Penaeus aztecus) Allergy (새우(Penaeus aztecus)의 알러지 억제를 위한 감마선 조사)

  • 김재훈;이주운;육홍선;김정옥;변명우
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.3
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    • pp.437-441
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    • 2000
  • 감마선 조사기술을 이용하여 새우 알러지를 감소시키기 위해 본 연구를 실시하였다. 감마선 조사구(A), 감마선 조사후 가열처리구(B), 가열처리 후 감마선 조사구(C)로 실험구를 설정하고 1,3,5,7,10 kGy의 감마선을 조사하여 실험에 사용하였다. A 처리구로부터 새우의 근혈장 단백질 용액과 근섬유 단백질 용액을 준비하였고, B와 C처리구에서도 각각의 단백질 용액을 준비하였다. 각 단백질 용엑에 대한 환자 IgE와 mAb 4.9.5의 결합력을 ELISA로 조사하였다. 두 항체 모두 감마선 조사구의 단백질을 용액과의 결합력이 감마선 조사선량이 증가할수록 낮게 나타났고, 감마선 조사후 가열처리가 항체의 결합력을 감소시키는데 더 효과적이었다. SDS-PAGE 결과 감마선 조사된 새우 단백질의 전기영동적 분리 pattern에는 변화가 없었다. 이 결과는 적절한 선량의 감마선 조사가 새우 알러지를 감소시킬 수 있다는 것을 시사한다.

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Thermoacoustic Power Generation by a Spiral Heater in the Rijke Tube (Rijke 관에서 나선형 가열기에 의한 열음향 파워의 생성)

  • Kwon, Young-Pil
    • The Journal of the Acoustical Society of Korea
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    • v.29 no.8
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    • pp.491-496
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    • 2010
  • Thermoacoustic power generation by a spiral heater in the Rijke tube was analyzed numerically. In the analysis, variables were normalized by the angular frequency of the sound and the thermal diffusivity of the air. The effect of the heater wire diameter d, the spacing between wires P-d, and the air-current velocity $U_0$, upon the power generation was obtained and discussed. When the spacing is broad enough, the normalized velocity is $U_0{\approx}0.8$ and the diameter is $d{\approx}4$ for the maximum power generation. With decrease of the spacing, however, the power generation increases more than 5 times and becomes maximum around $d{\approx}2$, $P-d{\approx}3$. And the velocity $U_0{\approx}0.8$ for the maximum power generation is almost independent of the wire spacing.

가상 소화모델시스템 내에서 감마선 조사와 가열 처리된 Ovalbumin의 IgE-Binding Ability의 변화

  • Seo, Ji-Hyeon;Kim, Jae-Hun;O, Sang-Hui;Lee, Ju-Un;Byeon, Myeong-U
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2004.10a
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    • pp.412-415
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    • 2004
  • 본 연구는 감마선 조사를 이용한 알레르기 저감화 식품을 개발하기 위한 실용화 방법의 안전성을 검토하기 위해 실시되었다. 감마선 조사 후 가열 처리된 OVA는 전기영동상에서pepsin에 의해서 상당히 감소하는 것을 확인할 수 있었다. IgG 항체를 통해 살펴본 소화성은 intact OVA보다 증가하여 가수분해되기 쉬운 형태임을 알 수 있었다. 또한 효소처리 전의 IgE-binding ability는 현저히 감소하였고 최종 효소분해까지 일정하게 낮은 농도가 유지되어 가상 소화모델 시스템 내에서의 안전성을 확인할 수 있었다. 이상의 결과에서 감마선 및 가열 처리를 단독으로 시행하는 공정보다는 감마선과 가열을 병용하는 방법이 알레르기 저감 식품을 개발에 더욱 효과적일 것으로 사료된다.

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Effects of Heat Treatment on the Antigenicity of Gamma-Irradiated Egg White Albumin (감마선 조사된 난백 알부민의 항원성에 미치는 가열의 영향)

  • 이주운;육홍선;조경환;김미리;김천제
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.5
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    • pp.848-853
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    • 2001
  • This research was conducted to study the effects on antigenicities (allergenicity) and structural changes of gamma-irradiated hen’s egg albumin (ovalbumin, OVA) by heating. Three groups of OVA solution (2.0 mg/mL) were prepared; 1) heat treatment; 2) irradiation after heating; 3) heating after irradiation. Samples were isothermally heated and/or irradiated at the absorption dose of 10 kGy. Competitive indirect ELISA was individually formatted with egg-allergic patients IgE (P-IgE), and mouse murine monoclonal IgG (M-IgG) and rabbit polyclonal IgG (R-IgG) for evaluating bindinhg abilities of antibodies to OVA in the sample solutions. Binding abilities of antibodies to thermally denatured OVA were changed : R-IgG to the sample treated with above 6$0^{\circ}C$, M-IgG to that above 7$0^{\circ}C$, and P-IgE to that above 8$0^{\circ}C$, respectively. P-IgE did not well recognize OVA heated at 8$0^{\circ}C$ and the above. However, binding abilities of M-IgG and R-IgG highly in creased. Significant differences of binding abilities were not observed in all samples with the combination of heat treatment and irradiation, regardless the order of the treatment. Turbidity of samples in creased both by heating and by irradiation, and the increase by irradiation was much higher than by heating. These results showed that allergenicity of OVA reduced by gamma irradiation was not affected by heating.

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Changes in Physico-chemical Properties of Potato Starch by Microwave Heating Methods (마이크로파 가열방법에 따른 감자전분의 이화학적 특성변화)

  • Choi, Ock-Ja;Koh, Moo-Seok
    • Korean Journal of Food Science and Technology
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    • v.25 no.5
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    • pp.461-467
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    • 1993
  • The purpose of this study was to investigate the physico-chemical properties of potato starch heated with microwave. Two types of potato starches are prepared; in group A raw potato starch was heated with microwave and in group B potato starch was isolated from potato heated with microwave. Both groups were exposed to the microwave energy in a 560 W, 2,450 MHz oven for 60, 120, 180 and 300 seconds. As the microwave heating time took longer, free lipid decreased and bound lipid increased in both groups. The shape of starch granules, birefrigence and X-ray diffraction pattern were not changed much by microwave heating in both groups. Water binding capacity increased, but amylose content, swelling power and solubility decreased as the microwave heating time took longer. It was also found that the extent of decreases in swelling power and solubility were different between group A and group B.

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