• BMB Reports
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• 제46권1호
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• pp.53-58
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• 2013

We constructed deletion mutants and seven point mutants by polymerase chain reaction to investigate the specificity of feline foamy virus integrase functional domains. Complementation reactions were performed for three enzymatic activities such as 3'-end processing, strand transfer, and disintegration. The complementation reactions with deletion mutants showed several activities for 3'-end processing and strand transfer. The conserved central domain and the combination of the N-terminal or C-terminal domains increased disintegration activity significantly. In the complementation reactions between deletion and point mutants, the combination between D107V and deletion mutants revealed 3'-end processing activities, but the combination with others did not have any activity, including strand transfer activities. Disintegration activity increased evenly, except the combination with glutamic acid 200. These results suggest that an intact central domain mediates enzymatic activities but fails to show these activities in the absence of the N-terminal or C-terminal domains.

• Journal of Photoscience
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• 제8권3_4호
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• pp.99-104
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• 2001

Studies have been conducted to explore single electron transfer (SET) promoted photocyclization reactions of ($\omega$-phthalimidoalkylthio)acetic acids (alkyl=ethyl, n-propyl, n-butyl, n -hexyl and n-nonyl). Photocyclizations occur in methanol in modest yields to produce cyclized products in which phthalimide carbonyl carbon is bonded to the carbon of side chain in place of the carboxylic group. The initially formed cyclized products undergo efficient water eliminations to produce enthiol ethers in secondary ground state reactions.

• 한국정밀공학회지
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• 제25권4호
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• pp.118-126
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• 2008

A new approach to the critical speed calculation of general multi-mesh gear chain system included bevel gear is presented. A transfer matrix mode! based on Hibner's branch method is developed and the natural properties of the branched rotor system are calculated with using the ${\lambda}$-matrix formulation. A Campbell diagram, in which the excitation sources caused by the mass unbalance of the rotors, misalignment and the transmitted errors of the gearing are considered, shows that, at the neighborhood of the operating speed, there are the two critical speeds amplifying the first mode and the eighth mode.

• Macromolecular Research
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• 제14권5호
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• pp.539-544
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• 2006

2-Furancarboxaldehyde-2-pyridinylhydrazone (FPH) and 5-methyl-2-furancarboxaldehyde-2-pyridinylhydrazone (MFPH) were synthesized and used as tridentate ligands of copper (I) bromide for the atom transfer radical polymerization of methyl methacrylate (MMA) and styrene. The polymerization of methyl methacrylate achieved high conversion and yielded polymers with a good control of molecular weight and low polydispersity (PDI=1.33). Higher PDI were observed in the polymerization of styrene. Using 1-phenyl ethylbromide (PEBr) and ethyl 2-bromoisobutyrate (EBiB) as model compounds for the polymeric chain ends, the activation rate constants of the new catalytic systems were measured. These results were correlated with the polymerization results and compared with another catalytic system previously reported.

• Bulletin of the Korean Chemical Society
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• 제10권3호
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• pp.282-288
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• 1989

Theoretical analysis of DF-$CO_2$ transfer chemical laser is performed through simple kinetic model consisting of 30 chemical reactions. In this model, we calculate the power theoretically by solving the rate equations, which are related to the $D_2\;+\;F_2$ chain reaction and the DF-$CO_2$ resonance energy transfer, combined with both the gain processes and the stimulated emission processes. The calculated powers are verified with previously reported results in good agreements. The output energy rises linearly with the increase in pressure, and the duration time of output pulse show the inverse dependence on pressure. Through the detailed calculation of temperature and concentrations of reactants as a function of time, it is found that the deactivation processes of DF(v) can be neglected in low pressure, but they have to be considered in high pressure. From the parametric study for the variation on [$D_2]/[F_2$] and [$CO_2]/[D_2\;+\;F_2$] at several constant total pressure, the optimum lasing conditions are found to be in a range of 1/3 to 1 and 2 to 4, respectively.

• Journal of Radiation Protection and Research
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• 제31권4호
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• pp.211-217
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• 2006

원자력 시설의 가동에 따른 한국인의 식품 섭취 피폭 선량을 보다 현실적으로 평가하기 위해서는 농작물에서의 핵종 이동 계수에 대해 국내 생산 자료를 사용할 필요가 있다. 본 논문에서는 과거 수년간 한국원자력연구소에서 수행된 우리나라 주요 농작물의 핵종 이동 인자에 관한 결과를 분석하고 이를 외국의 사례와 비교하여 이를 사용할 때 선택할 수 있는 근거를 제시하고자 하였다. 이동인자의 경향은 실험의 횟수가 많을 경우 대체로 평균에 대해 정규분포를 이루는 경향을 보였으나 일부 핵종은 실험의 환경, 작물 및 토양의 종류에 따라 큰 변이를 보였다. 이러한 이동 인자들은 원자력 시설의 가동전이나 정상가동 중 또는 사고 시에 작물체내 방사성 핵종의 농도를 예측하고 평가하는 데 목적이나 환경에 따라 적절히 활용될 수 있다. 여기에 제시된 모든 인자는 대부분 온실 실험을 통하여 얻은 것이어서 몇 가지는 실험상의 제약으로 인하여 보수적이거나 단편적인 결과를 얻을 가능성이 있다. 따라서 본 논문에서 제시된 인자를 사용할 경우 각각의 의미와 한계를 충분히 숙지하고 평가의 목적이나 모델의 특성에 맞게 사용해야 하며, 그럴 경우 외국의 모델에서 제시된 인자를 사용할 때보다 현실적인 평가가 될 것으로 여겨진다.

• Elastomers and Composites
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• 제37권1호
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• pp.31-38
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• 2002

카르복실화 스티렌-부타디엔 라텍스의 중합시간은 사용되는 부타디엔 모노머가 공액 이중결합을 가진 화학적 구조로 인하여 라디칼 중합시 홀 전파의 비편재화로 인해 아크릴 에멀젼의 제조시 보다 중합시간이 매우 길다. 또한 라텍스 자체가 고분자와 분산매의 분리 없이 사용되기 때문에 라텍스의 안정성은 대단히 중요하다. 물성의 저하없이 반응시간을 단축하기 위하여 기존에 사용하던 연쇄이동제인 사염화탄소 대신 tert-dodecylmercaptane 과 ${\alpha}$-methylstyrene dimer를 혼합 사용하여 반응시간을 14시간에서 12시간으로 줄일 수 있었다. 반응 성장단계에서 아크릴산의 투입량을 0.3 part로 제한하여 라텍스의 점도 상승을 막고 초기중합단계 직후에 아크릴아미드를 0.1 part 첨가하여 라텍스 입자의 내부영역과 외부영역의 고분자 사슬의 상호간확산을 막아 단단하면서도 접착력을 유지할 수 있는 라텍스의 합성 결과를 얻었다.

• 한국임상수의학회지
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• 제17권1호
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• pp.234-237
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• 2000

The dornor, 2 years old, 20kg and mixed breed, was bred naturally on day 1 and day 3 of estrus and eight gastrulae were collected by flushing the uterus of the donor after laparatomy on day 13 after the second mating. The embryos were frozen by programmable freezer and preserved for about 3 months in liquid nitrogen. Another bitch in natural estrus, 2 years old, 30kg, mixed breed, was selected as the recipient and the frozen embryos(8 gastrulae) were thawed and each 4 embryos were transferred into upper partr of left and right uterine horn, respectively, on day 13 after the proper mating day determined by vaginal smear. The ecipient delivered 6 offspring 48 days after embryo transfer. Of 6 puppies, one was still birth and two puppies died one month after birth. Parentage test was performed by DNA analysis using microsatellite sequences for 3 puppiers, the recipient, the donor, the male dog bred with the donor, and the male dog raised near to the recipient. The markers selected for the test were CXX 873(133-157 base pair) and CXX 894(141-165 base pair). Using primers manufactured according to the markers, the blood samples were processed for polymerase chain reaction and the PCR products were treated for electrophoresis. The three puppies showed identical band to that of recipient, consequently, it was concluded that the puppies were offspring of the recipient mated naturally by the male dog, not the offspring by embryo transfer.

• 한국ITS학회 논문지
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• 제17권6호
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• pp.67-83
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• 2018

본 연구를 아우르는 질문은 "지하철 역사내부를 이동하는 개별승객은 언제 어디서 어떤수단을 이용해서 출발해서 언제 어디로 어떤 수단을 이용해서 갔는가 ?"이다. 이 물음에 답하기 위해서는 지하철 역사를 이동하는 개별승객이 이용한 정류장, 경로, 수단에 대한 파악이 선행되어야 한다. 수도권 통합대중교통요금체계에서는 AFC(자동요금징수체계)자료를 활용하면 개별대중교통이용승객의 통행수단, 정류장, 경로가 파악된다. 본 연구는 AFC자료를 이용하여 수도권의 대중교통역사의 승객이동을 지하철 환승역사의 관점에서 관찰하는 SSA(선별역사분석) 기법을 제안한다. SSA는 환승역사내 개별승객이동을 세분화하고 연계통행관점에서 최초출발역/시간과 최종도착역/시간 정보를 분석한다.

• 무역학회지
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• 제46권6호
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• pp.93-107
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• 2021

The bill of lading serves to link imports and exports. It is the last document issued in the export process and is the most important document before import and export as it is the first document required for importers to take over goods. Transfer the right to the goods to be transported to another person through endorsement. The role and importance of the bill of lading has already been suggested in many previous studies and the trading partners are fully aware of it. In addition, all countries and international organizations recognized the importance and enacted various laws and systems in relation to possible legal problems and they have become customary in practice. However, trade fraud that exploits the characteristics of the bill of lading may occur. In order to solve this problem, various attempts related to the electronic rights transfer of the bill of lading began to be carried out, and many institutions and companies are still trying to develop a new system. As a result of these efforts, electronic bills of lading, such as bolero, appeared, and electronic bills of lading, which can transfer rights in an electronic way, appeared. Therefore, this study intends to present the feasibility of the introduction of smart bills of lading after examining the current status of electronic bills of lading and the introduction of block chain technology-based bills of lading.