• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 1999년도 춘계 공동학술발표회
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• pp.254-256
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• 1999

• Design & Manufacturing
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• 제17권3호
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• pp.1-7
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• 2023

Blow molding is a manufacturing process in which thermoplastic preforms are preheated and then pneumatically expanded within a mold to produce hollow products of various shapes. The two-step process, a type of blow molding method, requires the output of multiple infrared lamps to be adjusted individually, so the process of finding initial conditions hinders productivity. In this study, digital twin technology was applied to solve this problem. A blow molding simulation technique was established and simulation-based metadata was generated. A response surface ROM (Reduced Order Model) was built using the generated metadata. Then, a dynamic ROM was constructed using the results of 3D heat transfer analysis. Through this, users can quickly check the product wall thickness uniformity according to changes in the control value of the heating lamp for products of various shapes, and at the same time, check the temperature distribution of the preform in real time.

• 한국통신학회논문지
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• 제29권4C호
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• pp.485-493
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• 2004

파장/시간 2차원 광 코드 분할 다중화 방식 (OCDMA)에 대한 시스템의 성능은 신호와 다중 사용자 간섭 사이에 비트 잡음이 일어나는 것에 의해 제한된다. 본 논문에서는 OCDMA시스템에서 비트 잡음에 대한 영향을 분석한 것으로써 비트 잡음이 있을 때와 비트 잡음 없을 때의 OCDMA성능을 분석하였으며 이를 극복하기 위한 방법으로 OHL (Optical Hard-Limiter)를 수신단에 포함하는 방법을 제안하고 이 때의 성능평가를 수행하였다. 성능 평가를 위해 사용되는 코드는 대칭적이고 비대칭적인 prime-hop 2차원 코드를 사용하였다. 분석결과 코드가 대칭인 경우 성능은 비트잡음이 있을 때 OHL가 있는 경우와 제안한 OHL을 사용한 경우 약 3.5배의 성능 향상을 보이며 비트 잡음이 없는 경우 OHL이 없는 경우와 제안한 OHL이 있는 경우 1.5배의 성능 향상을 확인 할 수 있었다.

• 한국산업보건학회지
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• 제19권1호
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• pp.30-38
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• 2009

The objective of this study was to evaluate the effects of occupational exposure to styrene on the components of metabolic syndrome. We surveyed 263 employees, among whom 117workers we ere chronically exposed to styrene in glass-reinforced plastic boat manufacturing factories and 146 controls had never been occupationally exposed to styrene as will as hazardous chemicals. The general and job characteristics such as age, smoking and drinking habit, working hours and duration were not significant different except sleeping hours(p<0.05). Among the components of metabolic syndrome, the systolic blood pressure, total cholesterol, HDL-cholesterol and fasting glucose were significantly higher in exposed workers. On multiple logistic regression analysis for the components of metabolic syndrome, waist circumference was insulin (OR=1.129), blood pressure was MA(OR=14.724), fasting glucose(OR=1.191) and metabolic syndrome(OR=1.110) were significantly associated with insulin. The mean concentration of airborne styrene was $ 38.1{\pm}40.1$ ppm, blood concentrations of glucose and insulin and levels of HOMA-IR in over 50 ppm exposed group were higher than in blow 50 ppm exposed group. These results suggested that the exposure of styrene affects blood pressure, fasting glucose and insulin levels and that dysfunction and/or declination in glucose and insulin metabolism might induced ultimately insulin resistance and metabolic syndrome.

• Current Research on Agriculture and Life Sciences
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• 제9권
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• pp.71-86
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• 1991

This study has tried to illuminate a shocking phenomenon, the import liberalization of agricultural products in the aspect of Consumer consciousness. It has been applied that Table Analysis by using computer programming for instance-MINITAB, and Correlation Analysis and Multiple Regression Analysis, things like that. The results of this study are as follows; 1. Comparing domestic and imported stuffs, Comsumers came to awareness that domestic products superior to foreign's in the cases of the degree of freshness, taste and pollution damage, in the meanwhile, inferior to the cases of price and wrapping. Food self-supplyment is considered as one of the most important things of all, moreover, by most comsumers and health food and conventional food are favored by high class people. 2. Bying imported stuffs could clearly be fatal blow to our agriculture is fully recognized among consumers, what is more, there would only be doomed to our agriculture, too. 3. The most mass-purchasing imported stuffs by consumers illustrates in order; Beef, Banana, Coffee and Tabacco etc. The most significant elements why consumers buy foreign product is that the prices of them are relatively lower than those of ours. Besides, the next causes lies to non-producing stuffs and curiosity. 4. It must've been generally conceived by most consumers that Open-the-market-policy has been progressed for USA's repression and our monopolistic capital. Therefore, they demand that our market should be contained against unadviciable wave, moreover, keep paying attention to the policy how it will work to protect Korean agriculture. 5. Consumer attitude toward buying imported agricultural products is double-faced, Never-buy occupied only 24.4 % among respondents, but overwhelming respondents say non-producing stuffs can be obtained selectively. In this case, however, never-buy-movement would be backed by consumers in proportion to their educational background. 6. Various consumer minds surrounding Open-the-market-situation, in the end, has been analized econometrics through eleven variables to approach accurate fulfillments.