• Korean Journal of Veterinary Research
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• v.6 no.1
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• pp.10-17
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• 1966

The antigenecity of somatic substances of S. pullorum standard strain and variant strain extracted byheat treatment, acid treatment and their modification, ammonium sulfate saturation (60 per cent), trypsin digestion was tested by indirest hemagglutination test and precipitation test and following results were optained. 1. Teatment at $100^{\circ}C$ for an hour of the bacteria could extract the antigen of S. pullorum standard strain and variant strain which was demonstrable by hemagglutination reaction with the human a group and chicken red blood cell. 2. Trypsin digestion was more enhanced its antigenecity in acid extracted antigen of S. pullorum variant strain compare with the S. pullorum standard strain. 3. The extracted antigenic substances of S. pullorum standard strain existed chiefly in the elicited fraction of precipitate at the treatment of ammonium sulfate saturation and after trypsin digestion, its antigenecity was demonstrated by hemagglutination. 4. At the treatment of ammonium sulfate treatment, did not occur the precipicate in acid extracted antigens of S. pullorum variant strain, however, the heal extracted antigen, positive reactions were obtained in both of the precipitate and supernatant fraction of the S. pullorum variant strain by hemagglutination reaction. After trypsin digestion, these fraction also exhibited positive reactions. 5. Precipitation test also tested dub could not detect in any soft of the antigens.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.188-193
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• 2009

This study was conducted to determine the effect of mugwort powder on meat composition and sensory characteristics in finishing gilts $(LY{\times}D)$. Twenty pigs (75kg) were randomly allotted to four treatments. Mugwort powder was added to final concentrations of 0(C), 0.5(T1), 1.0(T2), and 1.5%(T3) in the basal diet. Pigs were fed with the specified diet for 50 days. Carcass characteristics and cooking loss were not significantly affected by mugwort powder supplementation. The WHC and cooking loss of T2 and T3 were not significantly different than the control. However, the pH values for meat from gilts fed the T1 and T3 diets were significantly lower than the control (p<0.05). Shear force values of fresh meat were highest with the T3 diet (p<0.05), while the shear force values of cooked meat were significantly lower than the control with the T2 and T3 diets. Texture values of hardness, brittleness, gumminess, chewiness, and adhesiveness were significantly higher with the T3 diet (p<0.05), however values for cohesiveness and springiness were not significantly affected by mugwort powder supplementation. These results indicate that the feeding of mugwort powder improves the shear force of cooked meat from gilts fed the T3 diet, however the carcass, WHC and cooking loss characteristics in gilts are not affected by mugwort powder supplementation.

• Clean Technology
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• v.11 no.4
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• pp.205-211
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• 2005

There have been many technologies and materials proposed for realizing microlens array, and plastic injection is recognized as the most promising one because of several merits such as optical properties, impact resistance, formability, lightening and environmental adaptability. Since PR reflow for injection template fabrication enables the lens shape control easier, and the sample technology more effective for mass production, it lowers the cost, enhances integration, and reduces process steps, which leads to be environmentally benign. However injection of polymers may face the difficulty of formability depending on their properties. In order to overcome the difficulty, fast heating/cooling technology was introduced in this study, and microlenses were fabricated and evaluated. template obtained by PR reflow method was heated and cooled fast during injection to fabricate microlens array. PC and PMMA polymer materials were compared, and it was realized that PMMA showed much better formability due to its lower melting temperature. Injection parameters of pressures and velocities were driven out for injection optimization.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.2
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• pp.190-195
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• 2009

This paper introduces experimental investigates of an electrical accident of the distributing cable termination with simulated a shoddy construction. We prepared two termination kites, one is built-in type, the other is heat contraction type. Also, we manufactured cable termination that have simulated defect by badness construction and investigated their insulation characteristics such as ac (35[kV], 1[min]) and impulse (95[kV], $1.2{\times}50[{\mu}s]$) withstand test. The influence of defects such as thickness decrease, the gap between stress-con of housing and semiconductor and heating time on insulating properties of the termination have been studied. The thickness decrease of an insulator decreases ac breakdown strength suddenly and the breakdown traces of the insulator that is damaged by knife displayed elliptic shape. The gap of between stress-con and semiconductor deteriorates dielectric strength of insulator seriously. In heat contraction type, the ac breakdown voltage became low when the heating time is short.

• Korean Journal of Poultry Science
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• v.33 no.4
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• pp.283-293
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• 2006

Two experiments were conducted to investigate the effects of dietary activated charcoal mixed with wood vinegar (AC) on broiler performance and antibiotics residue in eggs. In experiment 1, a total of low hundred fifty, 1-day-old male broile. chicks (Ross) were divided into 6 groups, consisting 3 replicates of 25 birds each, and 134 one of the six experimental diets: devoid of AC and antibiotics (negative control), devoid of AC with 0.1% antibiotics (positive control), devoid of antibiotics with 1% AC, with 0.1% antibiotics and 1% AC, devoid of antibiotics with 2% AC, with 0.1% antibiotics and 2% AC, for 5 wks. Feed consumption and body weights were measured weekly. At the end of the experiment, eight birds from each group were selected and sacrificed. The relative weight of organs and characteristics of breast muscle were investigated. There were no significant differences in feed intake, body weight gain and feed conversion rate among the treatments. There were also no significant differences in the relative weight of breast meat, leg and liver. The abdominal fat tended to be decreased by the dietary AC. Significant differences were shown (P<0.05) in meat redness (a) and yellowness (b) among the treatments. However, the sensual characteristics of breast muscle was not affected by the dietary treatments. There were significant differences in total microbes, Coli forms and lactic acid bacteria (P<0.05) among the treatments. In experiment 2, a total of ninety, 40-wk-old Hy-line Brown laying hens were divided into 3 groups, consisting 3 replicates of 10 birds each and fed medicated control diet devoid of AC or diets containing 1% AC and 2% AC for 2 wks. The residue of antibiotics in Plasma and egg Yolk were significantly decreased (P<0.05) in 2% AC group compared to that of control. This study suggest that dietary AC may improve the external quality of edible meat and reduced antibiotics residue in chicken eggs without affecting laying performance.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.197-206
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• 2016

This work was carried out to investigate effects of the freezing/thawing method on duck meat kept in a freezer for a month. The meats used were breast muscle collected from Korean native ducks (KND) that were fed for 8 weeks (2.8 kg of live weight). Forty-five samples were used after being frozen in storage for one month and were then divided into 5 treatments (3 replications/treatment, 3 samples/replication). Five treatments (CON, FFFT, FFST, SFFT and SFST) were control groups (CON) and four were experimental groups, using $2{\times}2$ complex factors with two freezing methods (fast freezing, FF, $-50^{\circ}C$ in a deep freezer; slow freezing, SF, $-20^{\circ}C$ in a common freezer) and two thawing methods (fast thawing, FT, 5 h $12^{\circ}C$ with flow water; slow thawing, ST, 24 h $5^{\circ}C$ in a refrigerator). Lightness of KND meat in FF and FT groups was lower than that of control (P<0.05). Yellowness of KND meat of the ST group was higher than that of control (P<0.05). Cooking loss (CL) and water holding capacity (WHC) of KND meat in the control were lower than those of the freezing and thawing groups (P<0.01, P<0.05), but shear force (SF) of the control was higher than that of other groups (P<0.01). Moisture content of the ST group was higher than that of the FT group (P<0.05), and protein content of the FF group was higher than that of control (P<0.05). Stearic acid (C18:0) of the SF group was higher than that of the FF group (P<0.05). Arachidonic acid (C20:4n6) of control was higher than that of the SF and ST groups (P<0.01, P<0.05). Alanine, aspartic acid, glutamic acid, serine, and tyrosine content of the control were lower than that of the freezing and thawing groups (P<0.05). These results show that freezing and thawing methods affect meat color, shear force, cooking loss, and WHC-related water content.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 1997.06b
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• pp.11-12
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• 1997

니트로소디메틸아민이 발암성 물질이라는 것이 1954년 Barnes와 Magee에 의해 발견된 이래 이것이 지금까지 학자들에게 관심의 대상이 되고 있는 이유는 발암력이 강하여 극미량으로도 생체내에 암을 유발시킬 수 있을 뿐만 아니라, 대부분의 발암성 물질이 신체의 특정기관에 발암작용을 나타내는데 비해 이 물질은 신체의 여러 부위에 암을 유발시킬 수 있다는 점 그리고 이 물질이 햄, 소시지, 베이컨, 알코올음료, 김치 및 어류 가공품 등 어려 가지 식품에 널리 분포되어 있다는 사실 등을 들 수 있다. 니트로소 화합물은 구조로 보아 티트로소아민과 니트로소아미드로 구분되는데 전자는 제 2급 아연이 산화질소 유도체와 반응하여 생성된 니트로소 유도체이과 후자는 오소, 아미드 등이 치환된 니트로소 유도체로서 화학적인 성질이나 생물학적인 작용이 상이하다. 즉 니트로소아민은 식품에서 안정한 화합물인 반면에 대부분의 니트로소아미드는 불안정하다. 지금까지 연구된 바에 의하면 3백 여종의 니트로소 화합물에 대하여 동물실험을 행한 결과 발암성이 90% 이상 인정되었다. 식품 중 니트로소 화합물의 전구물질 중 질산염과 아질산염은 식품의 가공 저장 및 조리과정 중 니트로화의 된 전구물질인데 이는 육가공품의 색소고정, Cl. Botulinum에 의한 식중독 방지 및 풍미의 향상을 위하여 수 세기 동안 식품첨가제를 사용되어 왔으며, 유럽이나 미국 등지에서는 아직도 육가공품에 아질산염의 첨가가 논란의 대상이 되고 있다. 식품 중 니트로소 화합물에 대한 북유럽 식품 3천여 점을 분석한 결과 검출된 니트로소 화함물은 니트로소디메틸아민이 대부분이며 맥주에서 66%로 검출률이 가장 높았고 다음으로 염지육 및 치즈의 순 이었다. 조리한 일본산 해산 식품 중에 니트로소디메틸아민이 최고 313$\mu$g/kg, 캐나다산 해산 건조 식품에서는 67$\mu$g/kg, 홍콩산 염건어에는 1,400 $\mu$g/kg , 훈연어류에는 N-nitrosothiazolidine이 13,700 $\mu$g/kg , 우리 나라 해산 식품 중 니트로소디메틸아민은 건조가오리, 동결건조명태, 건조오징어, 굴비 및 소건새우 등에서 2.8~86.0 $\mu$g/kg 으로서 비교적 높은 양이 검출되었을 뿐 아니라 이들 식품을 조리할 경우 3.6~13배 증가하였다. 또한 김치와 젓갈류 중에서도 니트로소디메틸아민이 검출된다는 연구가 있다. 식품 중 니트로소 화합물의 생성율 억제시키기 위하여 최근 20여년간 연구된 바를 요약하면 아스코르브산과 같은 억제제의 첨가, 가공방법 및 조리방법의 개선이 비교적 바람직한 방법으로 인정되고 있다. 위의 방법을 적용하여 베이컨을 조리한 결과 낮은 온도에서 오랜 시간 가열하는 것이 높은 온도에서 짧은 시간 가열한 것보다 니트로화 반응이 훨씬 낮았고 또 마이크로웨이브로 조리하는 것이 니트로소아민을 최소화 시키는 방법이었다. 염지육은 아스코르브산이나 토코페롤 등의 니트로화 억제제를 첨가할 경우 니트로소 화합물이 현저히 감소 하였는데 이는 산화질소의 소거 능력이 우수하기 때문인 것으로 밝혀졌다. 가공방법의 개선으로서는 가공시 식품을 공기에 노출시킬 경우 특히 직화로 가열된 공기에 노출되면 니트로소아민의 생성이 매우 높은 것으로 보고되어 있는데 그 대표적인 예로 맥아를 직화로 건조할 경우 맥주 중에 니트로소 화합물이 훨씬 높은 양이 검출된다고 보고되어 있다. 대체로 식품의 가공 조리 및 저장 중 니트로소화합물에 대한 메커니즘은 상세히 밝혀져 있으나 생체내에서의 생성이나 억제 등에 대한 연구는 아직도 미흡한 실정이라이 분야에 대한 연구가 절실히 요구된다.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.531-536
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• 2016

The worldwide research and development for high-efficiency power generation system is progressing steadily because of the growing demand for reducing greenhouse gas emissions. Many countries have spurred the research and development of supercritical $CO_2$ power generation technology since 2000 because it has the advantage of compactness, efficiency, and diversity. Supercritical $CO_2$ power generation system can be classified into an indirect heating type and a direct heating type. As of now, most studies have concentrated on the development of indirect type supercritical $CO_2$ power generation system. In the United States, NREL(National Renewable Energy Lab.) is developing supercritical $CO_2$ power generation system for Concentrating Solar Power. In addition, U.S. DOE(Department of Energy) also plans to start investing in the development of the supercritical $CO_2$ power generation system for coal-fired thermal power plant this year. GE is developing not only 10MW supercritical $CO_2$ power generation turbomachinery but also the conceptual design of 50MW and 450MW supercritical $CO_2$ power generation turbomachinery. In Korea, the Korean Atomic Energy Research Institute has constructed the supercritical $CO_2$ power generation test facility. Moreover, KEPRI(Korea Electric Power Research Institute) is developing a 2MW-class supercritical $CO_2$ power generation system using diesel and gas engine waste heat with Hyundai Heavy Industries.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.173-180
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• 2010

This study was conducted to investigate the effects of dietary supplementation of mulberry leaves and dandelion extracts on performance, proximate composition, heating loss, drip loss, and blood characteristics of chickens. One hundred sixty broiler chicks were fed diets for five weeks containing 1% mulberry leaves extracts (T1), 2% mulberry leaves extracts (T2), 1% dandelion extracts (T3), and 2% dandelion extracts (T4). At the end of five week feeding experiment, broiler were slaughtered, and stored at $4^{\circ}C$. T2 resulted in much better weight gain and feed conversion than other treatment groups. As storage time increased, all treatment groups resulted in increased heating loss and drip loss (P<0.05) but no significant difference were observed among the treatment groups. In blood composition, GOT (glutamic oxaloacetate transaminase), GPT (glutamic pyrubic transaminase), total cholesterol, and triglyceride were significantly decreased by the supplementation of mulberry leaves and dandelion extracts compared to the control (P<0.05). Especially, T4 was significantly (P<0.05) more effective in improving blood composition compared to other treatment groups. However, no significant difference (P>0.05) were found in LDL-cholesterol among all treatment groups. In conclusion, these data indicate that compared to other treatments, supplementation of 2% dandelion extracts (T4) were most effective in decreasing total cholesterol and triglyceride and increasing HDL-cholesterol.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1112-1113
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• 2015

In the end of 2014, Changwon National University and TECHSTEEL Co., Ltd. had initiated a project on the development of a 300 kW-class HTS DC Induction Furnace(HTS DC IF) for preheating non-ferrous metal billets funded by the Korea Institute of Energy Technology Evaluation and Planning for 3 years. This is the one of the most realistic commercial machines applying the coated conductors. In this paper, the development progress of a 300 kW-class HTS DC IF was introduced. The major characteristics of the furnace including its capacity, structure and operation scheme were presented. For ensuring the successful design, a pre-validation study was performed through the electromagnetic, heat transfer and solid mechanical analysis using a multi-physics FEM tool. The aluminum billet was heated up to $540^{\circ}C$ under 1 T of the magnetic flux density at the center of the billet, and the simulation results were described in detail.