• 자원환경지질
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• 제47권3호
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• pp.275-289
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• 2014

가스하이드레이트가 육상 동토지역과 심해저 퇴적층에 막대한 규모로 부존되어 있음이 밝혀지면서 가스하이드레이트 연구개발 선도국가에서 수행한 최근의 가스하이드레이트 육상 및 해상 생산 시험 결과는 가스하이드레이트가 미래의 에너지 자원으로서 사용 가능성을 높이고 있음을 보여주고 있다. 캐나다 말릭 2002 프로젝트에서는 열수 순환법을 이용하여 5일간 약 $480m^3$의 가스를 생산하였고, 말릭 2006-2008 프로젝트에서는 감압법에 의해 6일간 안정적 연속 생산으로 $13,000m^3$의 누적 생산량을 보임으로서 감압법이 가스하이드레이트부터 가스를 생산하는 유효한 방법임이 입증되었다. 2012년도의 미국 알라스카 현장 시험은 $CO_2-CH_4$ 치환 (맞교환법)을 이용하여 $CO_2+N_2$ 혼합가스를 주입하고 메탄을 생산하는 최초의 시험으로서 약 $6,000m^3$의 혼합가스를 주입하여 일일 생산 최대 $1,270m^3$의 가스를 생산하였다. 최근의 가장 주목할 만한 성과로는 일본이 난카이 해구에서 2013년 3월 감압법을 이용한 세계 최초의 해상 생산 시험을 실시하고, 6일 동안 누적량 $120,000m^3$의 가스를 생산한 것이라 할 수 있다. 일본이 생산 시험을 위해 수행하였던 연구개발 결과와 기술적 이슈들은 2015년도에 생산 시험을 준비하고 있는 우리에게도 많은 시사점을 주는데, 특히 감압 시나리오에 따른 생산 공정 설계, 모래 유입 등 시험정 완결 기법, 생산시 지반 안정성 등 생산 시험 공정 기술 개발의 모든 공정 요소에 대한 면밀한 검토가 요구된다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권5호
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• pp.315-317
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• 2018

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4239-4242
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• 2012

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제20권1호
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• pp.37-50
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• 2016

A large eddy simulation (LES) of a turbulent channel flow is performed by using the third order low-storage Runge-Kutta method in time and second order finite difference formulation in space with staggered grid at a Reynolds number, $Re_{\tau}=590$ based on the channel half width, ${\delta}$ and wall shear velocity, $u_{\tau}$. To reduce the calculation cost of LES, algebraic wall model (AWM) is applied to approximate the near-wall region. The computation is performed in a domain of $2{\pi}{\delta}{\times}2{\delta}{\times}{\pi}{\delta}$ with $32{\times}20{\times}32$ grid points. Standard Smagorinsky model is used for subgrid-scale (SGS) modeling. Essential turbulence statistics of the flow field are computed and compared with Direct Numerical Simulation (DNS) data and LES data using no wall model. Agreements as well as discrepancies are discussed. The flow structures in the computed flow field have also been discussed and compared with LES data using no wall model.

• 마이크로전자및패키징학회지
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• 제21권4호
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• pp.83-89
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• 2014

Solder paste plays a crucial role as the widely used joining material in surface mount technology (SMT). The understanding of its behaviour and properties is essential to ensure the proper functioning of the electronic assemblies. The composition of the solder paste is known to be directly related to its rheological behaviour. This paper provides a brief overview of the solder paste behaviour of four different solder paste formulations, stencil printing processes, and techniques to characterize solder paste behaviour adequately. The solder pastes are based on the Sn-3.0Ag-0.5Cu alloy, are different in their particle size, metal content and flux system. The solder pastes are characterized in terms of solder particle size and shape as well as the rheological characterizations such as oscillatory sweep tests, viscosity, and creep recovery behaviour of pastes.

• Parasites, Hosts and Diseases
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• 제48권3호
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• pp.245-246
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• 2010

Post kala-azar dermal leishmaniasis (PKDL) is a rare disease. This is a solitary case report from Orissa, India. We describe a case of PKDL in a 55-year-old male who presented with multiple nodular lesions over face, trunk, and extremities. The patient had been to an endemic area of kala-azar and had a previous history of leishmaniasis. Fine needle aspiration cytology samples from skin nodules revealed Leishmania amastigotes.

• Advances in Traditional Medicine
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• 제3권3호
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• pp.123-128
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• 2003

Stephania hernandifolia belonging to the family Menispermaceae is the biggest storehouse of diphenylbisbenzylisoquinoline (DBBI) alkaloids. Exhaustive chemical processing of the bulb of S. hernandifolia by the application of modern separation techniques yielded a DBBI alkaloid which was identified as cycleanine using spectroscopic methods (UV, IR, $^1HNMR$. $^{13}CNMR$, Mass). Cycleanine showed significant anti-inflammatory activity against carrageenin induced paw oedema, comparable to that produced by diclofenac sodium, used as standard drug. It exhibited potent analgesic effects against chemical and thermal noxious stimuli. It was also found to possess anticonvulsive activity in the strychnine induced convulsion model.

• Electronic Materials Letters
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• 제14권6호
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• pp.784-792
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• 2018

In this letter, a standard deviation based optimization technique has been applied on High Resolution X-ray Diffraction symmetric and asymmetric scan results to accurately determine the Aluminum molar fraction and lattice relaxation of Molecular Beam Epitaxy grown compositionally graded Aluminum Gallium Nitride (AlGaN)/Aluminum Nitride/Gallium Nitride (GaN) heterostructures. Mathews-Blakeslee critical thickness model has been applied in an alternative way to determine the partially relaxed AlGaN epilayer thicknesses. The coupling coefficient determination has been presented in a different perspective involving sample tilt method by off set between the asymmetric planes of GaN and AlGaN. Sample tilt is further increased to determine mosaic tilt ranging between $0.01^{\circ}$ and $0.1^{\circ}$.

• Journal of Microbiology
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• 제44권5호
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• pp.473-479
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• 2006

A well characterized naphthalene-degrading strain, Pseudomonas putida PpG7 was observed to utilize limonin, a highly-oxygenated triterpenoid compound as a sole source of carbon and energy. Limonin concentrations evidenced a 64% reduction over 48 h of growth in batch cultures. Attempts were made to acquire a plasmid-less derivative via various methods (viz. Ethidium Bromide, SDS, elevated temperature & mitomycin C), among which the method involving mitomycin C ($20{\mu}g/ml$) proved successful. Concomitant with the loss of plasmid in P. putida PpG7 strain, the cured derivative was identified as a $lim^-$ phenotype. The $lim^+$ phenotype could be conjugally transferred to the cured derivative. Based on the results of curing with mitomycin C, conjugation studies and presence of ndo gene encoding naphthalene 1,2 dioxygenase, it was demonstrated that genes for the limonin utilization were encoded on an 83 kb indigenous transmissible Inc. P9 NAH plasmid in Pseudomonas putida PpG7 strain.

• The Journal of Asian Finance, Economics and Business
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• 제4권3호
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• pp.45-56
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• 2017

Considerable research has been done on the issue of succession in family businesses. However the process of induction, of preparing the members of the next generation for joining the family business has not been examined in detail. This paper attempts to analyse the relevance of three critical factors - 'quality of relations', 'willingness of the inductee' and 'the ability to manage tensions harmoniously' - to the induction process and the progress of the business. It focuses on the Indian context, specifically in the Small and medium Enterprise (SME) area. Qualitative research has been carried out. The Case Study method is used and data has been gathered from two families (including two branches of one family), using frequent unstructured interviews, over a period of five years. It is concluded that positive impact on business, family and the inductee depends to a large extent on the quality of relations, willingness of the inductee and the ability of both the inductor and inductee to handle and manage the tensions. Thus the findings of the study extend current understanding about succession drivers to the specific context of eastern cultural and developing economy represented by the Indian family businesses in the small and medium enterprise sector.