• Nuclear Engineering and Technology
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• 제49권8호
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• pp.1752-1757
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• 2017

The aim of this study is to evaluate the radioactivity levels and radiological impacts of representative black sand samples collected from different locations in the Rashid area, Egypt. These samples were prepared and then analyzed using the high-resolution gamma ray spectroscopy technique with a high-purity germanium detector. The activity concentration ($A_c$), minimum detectable activity, absorbed gamma dose rate, external hazard index ($H_{ex}$), annual effective dose rate equivalent, radium equivalent, as well as external and internal hazard index ($H_{ex}$ and $H_{in}$, respectively) were estimated based on the measured radionuclide concentration of the $^{238}U$($^{226}Ra$) and $^{232}Th$ decay chains and $^{40}K$. The activity concentrations of the $^{238}U$, $^{232}Th$ decay series and $^{40}K$ of these samples varied from $45.11{\pm}3.1Bq/kg$ to $252.38{\pm}34.3Bq/kg$, from $64.65{\pm}6.1Bq/kg$ to $579.84{\pm}53.1Bq/kg$, and from $403.36{\pm}20.8Bq/kg$ to $527.47{\pm}23.1Bq/kg$, respectively. The activity concentration of $^{232}Th$ in Sample 1 has the highest value compared to the other samples; this value is also higher than the worldwide mean range as reported by UNSCEAR 2000. The total absorbed gamma dose rate and the annual effective dose for these samples were found to vary from 81.19 nGy/h to 497.81 nGy/h and from $99.86{\mu}Sv/y$ to $612.31{\mu}Sv/y$, which are higher than the world average values of 59 nGy/h and $70{\mu}Sv/y$, respectively. The $H_{ex}$ values were also calculated to be 3.02, 0.47, 0.63, 0.87, 0.87, 0.51 and 0.91. It was found that the calculated value of $H_{ex}$ for Sample 1 is significantly higher than the international acceptable limit of <1. The results are tabulated, depicted, and discussed within national and international frameworks, levels, and approaches.

• 한국콘텐츠학회논문지
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• 제16권12호
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• pp.399-409
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• 2016

최근 자동차시장은 친환경, 고연비, 무인자율주행을 앞세우고 빠르게 변해가고 있다. 자동차시장에서 국내 자동차산업이 성장하기 위해서는 IT, 마케팅, 광고/홍보, 생산/제조, 유통 등 다양한 기업들이 융 복합된 글로벌가치사슬(GVC) 생산시스템을 더욱 필요하게 되었다. 본 연구의 목적은 국내 자동차산업에서 부품중소업체들이 글로벌 완성차업체의 GVC내로 진입하기 위한 지원 방안을 찾아보고 이를 위해 GVC내 완성차업체와 부품업체 사이의 현황과 협력관계를 살펴보는 것이다. 또한 자동차산업의 완성차업체 GVC내 부품중소기업들이 진입하는데 필요한 정책방향을 현실성 있고 지원 가능한 방안을 찾아보는 것이다. 자동차산업에서 완성차업체의 GVC내로 부품중소기업이 진입하기 위해서는 GVC를 운영하는 대기업의 특성과 지배구조를 이해하고 맞춤형 전략을 수립해야 한다.

• 한국통신학회논문지
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• 제30권1C호
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• pp.35-43
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• 2005

본 논문에서는 팔레트 기반 이미지(palette-based image) 또는 인덱스 이미지(indexed image)라고 불리는 256색의 이미지에 대한 압축 성능 향상을 위한 새로운 알고리즘을 소개한다. 제안한 방식은 현재 색상이 갖는 인덱스 값을 중심으로 다음에 나오는 색상의 인덱스가 얼마나 발생하는지를 측정하고, 발생 빈도를 정렬하여 순위를 구한 후에, 색상에 대한 인덱스 값을 순위로 표현하여 원래의 인덱스 이미지를 대체한다. 그렇게 변화된 순위 인덱스이미지(ranked index image)의 인덱스 분포에서는 순위가 높은 곳에 같은 인덱스들이 더 많이 존재하기 때문에 데이터 중복성(redundancy)을 높일 수 있어, 압축 효율을 기대할 수 있다. 실험 결과에서는, 기존의 산술부호화 방식, 휘도 성분 기반의 JPEG-LS 방식 그리고 인덱스 기반의 GIF 방식들과 비교할 때, 원 이미지에 대한 압축률이 최대 22.5까지 향상되어 제안한 방식의 압축 성능이 훨씬 뛰어나다는 것을 보여준다.

• International Journal of Industrial Entomology and Biomaterials
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• 제25권1호
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• pp.93-98
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• 2012

Nutrition value of mealworm, Tenebrio molitor was analyzed due to increasing demand of usage as a protein source for domestic animals and even further for human consumption. The purpose of the present work was to determine the chemical compostion of the Tenebrio molitor larvae, adult that were maintained under standard condition for further usage of mass-rearing system and its exuvium, and excreta. Tenebrio molitor, larvae, adult, exuvium and excreta contained 46.44, 63.34, 32.87, and 18.51% protein respectively, suggested that even excreta could be used as an additional supplement in food recycling process. This protein was also rich in amino acids such as Isoleucine, leucine and Lysine which all met the nutritional value recommended by the Food and Agriculture Organization. Fatty acid composition was detected with high component of oleic acid (C18:1), along with linoleic acid (C18:2) and palmitic acid (C16) in all adult, larvae, exuvium and excreta. These oleic acid (C18:1), linoleic acid (C18:2) and palmitic acid (C16) components were the same or even highly contained in excreta of mealworm 22.29, 47.19 and 19.17% respectively. Longer chains of unsaturated fatty acids consisted of two to three double bonds are known as healthy product was recognized in large amount. These results show new ways to consume mealworms and its waste for animal and human consumption.

• Journal of Korea Trade
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• 제25권4호
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• pp.146-163
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• 2021

Purpose - This paper examines China's impact on Korea's ICT exports considering the direct competition channel, the production shift channel, and the indirect demand channel at once. This paper also takes China's economic rebalancing into account and discusses whether it makes any differences in the effect of the three channels. Design/methodology - To quantify the effect of the three channels, I constructed a linear panel regression model and estimated it with various estimation methods including the system GMM. China's exports toward the same destination as Korea's exports, Korea's exports toward China, and the third countries' exports toward China respectively reflect the three channels. China's GVC indicators are included as well to evaluate the effect of further China's economic rebalancing. Since the present paper has a greater interest in the effect of China rather than the determinant of bilateral trade, a (fixed effect) panel model becomes more appropriate than the gravity model because timeinvariant variables in the gravity model, such as the distance and the language, are eliminated during the estimation process. Findings - The estimation results indicate that Chinese ICT exports are complementary to Korea's ICT exports in general. However, when markets are considered in subgroups, China's ICT exports could have a negative effect in the long run, especially for SITC75 and SITC76 markets, implying a possible competitive threat of China. The production shift effect turns significant during China's economic rebalancing in the markets for the advanced economies and the SITC76 product. China's indirect demand channel is also in effect significantly for the advanced economy and SITC75 commodities during China's economic rebalancing periods. In addition, this paper shows that China's transition toward upstream in the global value chain could have a positive impact on Korea's ICT exports, especially at the Asian market. Originality/value - The contribution of this paper is threefold. First, it focuses on the ICT industry for which Korea increasingly depends on China and China becomes a global hub of the GVC. Second, this paper quantitatively studies three channels in a model in contrast to the literature which mostly examines those channels separately and pays less attention to the GVC aspect. Third, by utilizing relatively recent data from the period of 2001-2017, this paper discusses whether China's economic rebalancing affects the three channels.

• 한국경제지리학회지
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• 제26권3호
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• pp.274-288
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• 2023

농촌 개발 전략의 일환으로 글로벌 가치사슬로의 통합이 주목받고 있지만, 특정 통합이 성공 혹은 실패하는 원인과 메커니즘에 대해서는 알려진 바가 적다. 본 연구는 딸기 수출시장에서 진주지역의 농업인들이 생산자 주도적 가치사슬 거버넌스를 구축한 메커니즘과 그와 동반된 사회환경적 변화를 탐구했다. 이를 위해 딸기 가치 사슬의 특성을 분석했으며, 지대 이론에 의거해 진주와 논산을 비교 분석했다. 5개월에 걸친 현장조사와 이해관계자 심층 인터뷰 결과, 진주에서는 수출가능한 품종과 해당 품종에 적합한 지역 기후 조건으로 인해 자연적 진입장벽을 구축함으로써 수출시장에서의 경제적 지대를 창출했음을 확인했다. 또한 생산자 조직화를 통해 독점 지대와 국가 지원에서 비롯된 추가 수익을 유지했다. 수평적으로 연결된 농민들은 무역업체에 대한 협상력을 높이고 회원 가입을 통제하여 국가 지원에 대한 접근을 관리함으로써 생산자 주도적 가치사슬 내 지위를 공고화했다.

• Transactions on Electrical and Electronic Materials
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• 제17권3호
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• pp.163-167
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• 2016

Inverter surge resistant enameled wire was prepared with an organic/inorganic hybrid nanocomposite, and the effect of ambient temperature on the insulation lifetime of the enameled wire in the form of twisted pair was studied by a withstanding voltage tester. The organic polymer was Polyesterimide-polyamideimide (EI/AI) and the inorganic material was a Nano-sized silica (average particle size : 15 nm). The enamel thickness was 50 μm and the ambient temperature was 100, 150, 200, and 250, respectively. Transmission electron microscopy (TEM) observation showed that Nano-sized Silica were evenly dispersed in EI/AI. There were many air gaps in a twisted pair, therefore, when voltage was applied to the twisted pair, enamel erosion took place in the air gap area because of partial discharge accordi, ng to Paschen’s law. As ambient temperature increased, insulation lifetime decreased according to Arrhenius relationship, which was explained by the increasing mobility of polymer chains in EI or AI. And insulation breakdown voltage value at 10 kHz was 1,864.5 sec (31.1 min), which is 1.9 times higher than at 20 kHz, 981.6 sec (16.4 min).

• 경영정보학연구
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• 제11권3호
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• pp.191-207
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• 2009

연구에서 우리는 국내 및 국외의 자동차산업의 사례를 통해 과거의 제조중심에서 서비스 분야로 가치창출이 이루어짐을 보여준다. Servicizing이라고 불리는 이러한 새로운 전환은 새로운 IT기술에 의해 더욱 더 발전이 가속화 되고 있다. 이미, 미국, 일본, EU등에서는 산업의 경쟁력 향상을 위해 전략적으로 추진하고 있다. 단지 자동차 산업뿐만 아니라 물류, 보험 등 연관산업에까지 파급효과가 크기 때문인 것으로 풀이되고 있다. Telematics, 충돌방지 시스템, 중고자 판매, 렌탈등의 다양한 분야에 어떻게 IT기술이 응용되고 있고 부가가치가 창출되는지 다양한 사례를 본 논문에서 보이고자 한다.

• BMB Reports
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• 제28권2호
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• pp.138-142
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• 1995

An anticoagulant/fibrinolytic protease was purified to homogeneity from the earthworm Lumbricus rubellus. The protein was a single chain glycoprotein of 32 kDa that exhibited strong proteolytic activity on human thrombin and fibrin clots. Proteolytic degradation of these plasma proteins by the purified enzyme occurred at a neutral pH range. Among several human plasma proteins tested as possible substrates for the protease reaction, the 32 kDa enzyme specifically hydrolyzed both thrombin and fibrin polymers without affecting other proteins, such as serum albumin, immunoglobulin, and hemoglobin. Treatment of the purified enzyme at neutral pH with either phenylmethylsulfonylfluoride or soybean trypsin inhibitor resulted in a loss of catalytic activity. The enzyme hydrolyzed the chromogenic substrate H-D-Phe-L-Pipecolyl-L-Arg-p-nitroanilide with a $K_m$ value of 1.1 ${\mu}M$ at a neutral pH. These results suggest that the anticoagulant/fibrinolytic enzyme from Lumbricus rubellus is a member of the serine protease family having a trypsin-like active site, and one of the potential clevage sites for the enzyme is the carbonyl side of arginine residues in polypeptide chains.

• The Korean Journal of Pain
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• 제9권2호
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• pp.336-339
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• 1996

Stellate ganglion block which usually practiced in pain clinics may combined with hemodynamic changes because it blocks sympathetic nerve chains. We measured the hemodynamic changes with NCCOM3-$R7^{(R)}$ (BOMED, U.S.A.) which applicated bioimpedance method in twenty-two patients. Mean arterial pressure, heart rate, cardiac output, ejection fraction and left ventricle end diastolic volume (LEDV) were measured before stellate ganglion block (control), 1, 3, 5, 10 and 20 minutes after stellate ganglion block with 8 ml of 0.25% bupivacaine. The results were as follows: Mean arterial pressure decreased significantly (p<0.05) in 10, 20 minutes after stellate ganglion block comparing to control, but not clinically significant. Heart rate, cardiac output, ejection fraction and LVEDV showed no significant change compared to control value. These results showed that stellate ganglion block is a safe technique without significant hemodynamic changes.