• Applied Microscopy
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• v.31 no.4
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• pp.315-323
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• 2001

In situ TEM heating experiments utilizing kaolinite powder samples result in the following facts. (1) The water recirculation system adopted in the Gatan's heating holder is required to prevent specimen drift above $500^{\circ}C$. (2) Since the degree of phase changes depends on the thickness of powders below $600^{\circ}C$, examinations of both thin and thick specimens are required. (3) Sample preparation using Mo-grids is required for TEM heating experiments above $900^{\circ}C$. At these temperature ranges the effect of heating rate and holding time on the phase transition process increases drastically, so that a programmed temperature control is required. (4) TEM heating experiments of the embedded powders by epoxy for the cross-sectional view was limited due to the severe epoxy movement during heating above $300^{\circ}C$. Better methods of sample preparation are required to overcome this problem.

• Food Industry
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• s.220
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• pp.22-65
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• 2011

${\bigcirc}$ 본 업소는 냉동식품(냉동만두류, 냉동면류, 냉동피자)를 생산하는 식품제조 가공업소로서 총 5명의 인원이 냉동식품 3개 제품을 생산하여 매출액은 (약00원)이며 주로 대형 유통 판매업소에 판매하고 있다. ${\bigcirc}$ 본 업소의 냉동식품은 축산물(돈육) 농산물 등과 밀가루, 소금 등을 배합 성형 후 가열 등의 공정을 거쳐 생산된 제품으로 원료 취급과정에서의 오염이나 불충분한 가열, 교착오염 등으로 식중독균(병원성대장균, 황색포도상구균등)과 원료 및 제조과정에서 이물(금속등)이 혼입할 수 있으며, ${\bigcirc}$ 이로 인한 주요클레임 발생사례는 최근 3년간 관계당국으로부터 대장균군 검출 3건, 소비자클레임 2건이 있었다. - 연도별 주요 클레임내용은 '08년도에는 대장균군 검출 3건(냉동만두류), '09년도 날벌레 이물검출 1건(냉동피자), '10년도에는 철수세미1건(냉동면류)이었다. ${\bigcirc}$ 이러한 위해발생을 사전에 예방하기 위해 중점관리해야하는 공정은 가열(중숙, 탕숙, 가열 굽기)공정, 세척공정으로 판단되며, 금속 등의 이물 혼입 또한 중점적으로 관리할 필요성이 있다. ${\bigcirc}$ 본 업소에서 생산하는 냉동식품(냉동만두류, 냉동면류, 냉동피자)는 가열(중숙/탕숙/가열/굽기)공정 및 세척공정에서의 가열(중숙/탕숙/가열/굽기) 후 품온을 설정하여 CCP 1로, 세척시간과 세척수량, 원물량을 설정하여 CCP 2로 관리하고 있으며, 2시간마다 모니터링하고 한계기준 이탈여부를 기록하도록 하고 있다. ${\bigcirc}$ 종합적인 공정 및 일반위생관리를 위해 개인위생 상태, 냉동 냉장고 온도 확인 등 총 30개 항목에 대하여 정기적 점검(매일 18, 주간 4, 월간 4, 분기 1, 연간 3)을 실시하고 있으며, ${\bigcirc}$ 따라서 지속적인 모니터링을 통해 미흡사항의 원인으로 파악하고 문제점 제거를 위해 체계적이고 지속적인 관리가 필요한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2441-2451
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• 2012

This paper presents the design of a control system for improving performance of a washer fluid heating system (WFHS) which is capable of removing frost, ice, snow and/or other debris from windshield. First, for the WFHS, a modeling process is described, and the extraction of characteristic parameters of the model are made by experimental studies. Design variables that affect on performance of the WFHS are also presented. Secondly, a control system is proposed for improving heating performance of the WFHS, and its performance is verified through experiments. The key feature of the proposed control system is to regulate the current of a booster converter input to the WFHS up to the target value that is set to guarantee heating performance. Target current is calculated by using initial temperature value and employing the mathematical model derived in the paper. Computer simulation and experimental results show that the proposed control system can perform heating operations in a way to satisfy per-determined target performance of the WFHS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.70-74
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• 2001

The effects of aging time (1, 8 and 15 days) and endpoints cooking temperature (70, 75 and $80^{\circ}C$) on the physicochemical and sensory characteristics of pork neck were evaluated. Pork neck was obtained from the carcass (live weight, 105~110 kg ; grade B) chilled for 24 hours after slaughter. As a aging period became longer, the pH, L value and drip loss became higher while its a value and shear force value (SFV) of raw meat became lower. As a aging period became longer, the cooking loss, hardness, chewiness, SFV became lower, and its tenderness, juiciness and taste became better. However, no difference was observed in the aroma, and the one aged for 8 days in the cooked meat showed the best palatability. Increasing endpoint cooking temperature from 70 to $80^{\circ}C$ increased hardness, SFV and taste, and decreased chewiness, sensory tenderness and juiceness (p<0.05). However, it had no effect on the cohesiveness. Also, the one for which the endpoint cooking temperature became $75^{\circ}C$ in the cooked meat showed the best springiness, aroma and palatability.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.2
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• pp.34-44
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• 2002

Approximately 70 percent of shop's hull plate consists of three-dimensional curved shell. Concerning with the research on the automation of plate forming many studies have been carried out for the last decade. The purpose of this study is to develop the simulator of heating on the basis of the reasonable mechanical model representing a heating phenomenon. The beating experiment has been carried out with varying parameters influencing on the results of heating information at the kinematics analysis, simulatorestimate 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 variable.

• Food Science and Preservation
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• v.8 no.3
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• pp.338-344
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• 2001

The oxidative stability of cholesterol in tallow heated at different frying temperatures (130$\^{C}$, 150$\^{C}$, and 180$\^{C}$) was studied by identifying cholesterol oxides by thin layer chromatography(TLC). And fatty acid compositions in tallow heated were also measured and compared with cholesterol oxides. Unsaturated fatty acid contents slightly decreased as the heating time increased, whereas saturated fatty acid contents increased This phenomenon became excessive especially by heating to higher temperature. It was found that RF value and spot color of the nonsaponifiable lipids from tallow heated on TLC analysis accorded with the synthetic cholesterol oxides in this experiment. Four kinds of cholesterol oxides were detected in tallow heated for 24 hours at three different temperatures. The oxides were identified as 7-$\alpha$-hydroxycholesterol, 7-$\beta$-hydroxycholesterol, 7-ketocholesterol and cholesterol epoxide. It was found that there was a little difference in oxidative pattern of cholesterol between several heating temperatures.

• The Korean Journal of Food And Nutrition
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• v.13 no.6
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• pp.529-533
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• 2000

The marsh calm soup was prepared with 2 volumes of boiling water and heated for 0, 5, 10, 30, 60 and 120 minutes. As the boiling time prolonged, water content decreased gradually, while protein content increased. Free amino acid content was the highest with 30 minutes of boiling showing 103.1 mg/100g, and decrease showly thereafter. Among the free amino acids, alanine was the most abundant followed by proline, glutamic acid and glycine. Degree of protein hydrolysis increased as boiling prolonged. In the non-volatile organic acids, succinic acid was the highest(137.08 mg/100g with 30 minutes of boiling), followed by oxalic acid, magic acid and lactic acid. The optimum boiling time for marsh calm soup was evaluated to be 30 minutes.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.344-349
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• 2007

NaY zeolites synthesized by microwave heating were compared with those obtained by conventional heating. When the same temperature increasing rates were adopted in both heating methods, the microwave heating shortened the induction period and enhanced the rate of crystallization of NaY zeolites compared with the conventional heating. Irrespective of microwave radiation, the fast temperature increasing rate also shortened the induction time and enhanced the crystallization of NaY zeolites. The crystal sizes of NaY zeolites were large under the fast temperature raise of the reaction mixture and became larger by microwave radiation. At the same time, the fast temperature increasing rate has reduced the energy consumption due to the fast completion of reaction during the synthesis of NaY zeolite. The energy consumption in the conventional ethylene glycol bath was lower than that in the microwave oven with the same temperature increasing rate in this study, which means that the energy efficiency is not always high in microwave heating. If the temperature increasing rate is carefully controlled, however, NaY zeolite can be produced with high energy efficiency in the microwave oven.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.680-689
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• 1995

Rice based infant foods of carrot, of beef, and of egg for 4-6 month old infants were prepared using freeze drying (FD) process. The optimum moisture content prior to FD and the plate temperature in the drier were determined with the use of response surface methodology. For all the infant foods under this study, FD time was longer as the initial moisture content was higher and the plate temperature was lower. Brittleness of the dried infant foods increased as the moisture content decreased and the plate temperature increased. Among the sensory attributes, hydration rate, uniformity, and smoothness were greater with increased moisture content and with decreased plate temperature. Ease to spoon increased as moisture content increased and mouthcoating increased as both the moisture content and the plate temperature increased. Optimum moisture content and plate temperature for the FD of carrot, beef and egg foods were 88.5% and $34^{\circ}C$, 88.5% and $28^{\circ}C$, and 87.3% and $39^{\circ}C$, respectively.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1119-1123
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• 2008

Tin oxide was prepared by microwave heating for anode material of lithium ion battery. The samples were heated at 300, 500 and $700^{\circ}C$ for 3h under flowing oxygen after microwave heating. The effect of microwave heating on the electrochemical performance of the manufactured tin oxide and the reversible capacity performance were investigated. Tin oxide heated at $500^{\circ}C$ showed higher capacity than those at $300^{\circ}C$ and $700^{\circ}C$ under microwave heating condition. Comparing microwave and furnace heating, microwave heating condition showed higher capacity. The discharge capacity after microwave heating and $500^{\circ}C$ heating showed 1,500 mAh/g.