• Venture DIGEST
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• s.58
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• pp.14-15
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• 2004

미래학자 존 나이스빗은 이제 더 이상 한국이 다른 아시아 경제국들을 상대로 경쟁할 것이 아니라 어떻게 세계무대에서 경제국으로 자리잡을 것인가를 고민할 때라고 역설하였다. 내수시장과 아시아시장을 넘어 세계로 향하는 우리경제의 성장동력. 세계시장에서 일류기업들과 어깨를 나란히 하고 있는 우리 벤처기업들의 경쟁력을 확인해보자

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.581-586
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• 1998

We investigated the effect of mechanical back side damage in Czochralski grown silicon wafer. The intensity of mechanical damage was evaluated by minority carrier recombination lifetime by laser excitation/microwave reflection photoconductivity decay method, degree of X-ray diffuse scattering, X-ray section topography, and wet oxidation/preferential etching methods. The data indicate that the higher the mechanical damage intensity, the lower the minority carrier lifetime, and the magnitude of diffuse scattering and X-ray excess intensity increased proportionally, and it was at Grade 1:Grade 2:Grade 3=1:7:18.4 that the normalized relative quantization ratio of excess intensity in damaged wafer was calculated, which are normalized to the excess intensity from sample Grade 1.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.453.2-453.2
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• 2014

그래핀을 수직으로 성장한 형태인 탄소나노월(Carbon nanowall; CNW)은 탄소를 바탕으로 하는 다른 나노물질에 비해 표면적이 상당히 넓은 물질로 전극에 활용하여 소자 성능향상을 기대 할 수 있다. 또한 탄소를 기반으로 하는 나노 구조물중에서 가장 높은 표면밀도를 가진다. CNW를 차세대 염료감응형 태양전지(Dye sensitised solar cells; DSSC)의 상대전극으로 사용한다면 기존대비 광변환 효율을 향상시킬 수 있어 새로운 상대전극으로 활용 가능하다. 또한 CNW는 다른 촉매 없이 직접성장이 가능함으로 불순물 제거공정이 필요하지 않고, 공정시간이 짧아 대량생산에 용의하다. 본 연구에서는 마이크로웨이브 PECVD 장비를 사용하고 메탄(CH4)을 반응가스로 사용하여 CNW 하부전극을 제조하였다. CNW 하부전극의 광 변환효율을 관찰하기위해서 합성시간을 변화를 주었다. 제조된 DSSC의 광 변환 효율을 측정하기 위해 Solar simulator 장비를 사용하여 제작된 cells의 효율을 측정하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.27-33
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• 2005

In this study, the process parameters in ceramics powder compaction are optimized for getting high relative densities of ceramic products. To find optimized parameters, the analytic models of powder compaction are firstly prepared by 2-dimensional rod arrays with random green densities using a quasi-random multiparticle array. Then, using finite element method, the changes in relative densities are analyzed by varying the size of Al₂O₃ particle, the amplitude of cyclic compaction, and the coefficient of friction, which influence the relative density in cyclic compactions. After the analytic function of relative density associated process parameters are formulated by aid of the response surface method, the optimal conditions in powder compaction process are found by the grid search method. When the particle size of Al₂O₃ is 22.5 ㎛, the optimal parameters for the amplitude of cyclic compaction and the coefficient of friction are 75 MPa and 0.1103, respectively. The maximum relative density is 0.9390.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.353-358
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• 1999

This study is to find out the effects of various iron concentrations on growth, feeding and feed efficiency of olive flounder, Paralichthys olivaceus, The growth rate, feeding rate and feed efficiency of olive flounder in each experiments were represented by the relative value. The relative growth rate and relative feed efficiency of olive flounder were kept almost constant below the iron concentration of 1.0 mg/$\ell$, but were significantly decreased above the 5,0 mg/$\ell$ iron concentration. The growth rate, feeding rate and feed efficiency of olive flounder exposed to 10.0mg/$\ell$ iron concentration were significantly decreased than that exposed to normal condition. From these results, it could be concluded that the high level of 5.0 mg/$\ell$ iron concentration in the bottom water would curtail production of olive flounder in coastal area.

• Economic and Environmental Geology
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• v.45 no.4
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• pp.385-396
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• 2012

The geochemical high-grade uranium anormal zone has been reported in the Shinbo mine and its eastern areas, Jinan-gun, Jeollabuk-do located in the southwestern part of Ogcheon metamorphic zone, Korea. In this paper is reported the time-relationship between deformation and growth of metamorphic minerals in the eastern area of Shinbo mine, which consists of the Precambrian metasedimentary rocks (quartzite, metapelite, metapsammite) and the age-unknown pegmatite and Cretaceous porphyry which intrude them, and is considered the relative mineralization time on the basis of the previous research's result. The D1 deformation formed the straight-type Si internal foliation which is defined mainly as the arrangement of elongate quartz, biotite, opaque mineral in andalusite porphyroblast. The D2 deformation, which is defined by the microfolding of Si foliation, formed S2 crenulation cleavage. It can be divided into two sub-phases, early crenulation and late crenulation. The former occurs as the curvetype Si foliation in the mantle part of andalusite. The latter occurs as S1-2 composite foliation which warps around the andalusite. The andalusite porphyroblast began to grow under non-deformation condition after the formation of S1 foliation which corresponds to the straight-type Si foliation. It continued to grow before the late crenulation phase. The age-unknown pegmatite intruded after the D2 deformation and grew the fibrous sillimanite which random masks the S1-2 composite foliation. The D3 deformation formed F3 fold which folded the S1-2 composite foliation, D2 crenulation, fibrous sillimanite. It means that the intrusion of pegmatite related to the growth of the fibrous sillimanite took place during the inter-tectonic phase of D2 and D3 deformations. The retrograde metamorphism is recognized by the chloritization of biotite and two-way cleavage lamellae which is parallel to the S1-2 composite foliation and the F3 fold axial surface in the andalusite porphyroblast. It occurred during the D2 late crenulation phase and D3 deformation. In considering of the previous research's result inferring the most likely candidate for the uranium source rock as pegamatite, it indicates that the age-unknown pegmatite intruded during the inter-tectonic phase of D2 and D3 deformations, i.e. during the retrograde metamorphism related to the uplifting of crust, and formed the uranium ore zone around the Shinbo mine.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.436-439
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• 2003

Urbanization is worldwide phenomenon and unexceptional in Korea. It is necessary in the spatial decision making steps to predict urban forms for the efficient land use. This study aims to develop urban growth model based on allometry which deals with relationships between urban populations and urban area. For the input data and accuracy assessments, various GIS techniques are used. Although this research is an exemplary urban growth model dealing with physical data only, it can be a good start to develop a more practical model having socio-economic sides for planning practices.

• Journal of Service Research and Studies
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• v.4 no.2
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• pp.37-47
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• 2014

Service industry is a fundamental field that takes sustainable development of state economy. However the development of service industry in our economy doesn't yet compare to level of developed countries. It is supported by the recent statistics of our service industry. This paper shows regional comparative analysis about the current status of the service industry based on the number of establishments and workers. Using the data of census on establishments in 16 cities and provinces, we analyze the relative ratio for the number of establishments and workers in service industry among total industry in Seoul metropolitan, Gangwon, Chungcheong, Honam, Youngnam and Jeju region. Also we analyze the relative ratio by provinces in each region. We used the data of census on establishment for 7 years from 2006 to 2012, we calculated the relative ratio of the number of establishments and workers in service industry for the 6 regions. And we analyzed the relative ratio by provinces in each region.

• Journal of Chest Surgery
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• v.40 no.7 s.276
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• pp.499-502
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• 2007

Left ventricular inflow obstruction can be caused by a persistent left superior vena cava (SVC) and a dilated coronary sinus. A 31-day-old male infant with secondum atrial septal defect (ASD) and bilateral SVC underwent an operation for treating his uncontrollable congestive heart failure. The preoperative 2-dimensional echocardiography showed a normally sized mitral valve shrouded by a dilated coronary sinus. The operation consisted of pericardial patch closure of the ASD, coronary sinus unroofing and left SVC transfer to the right atrial auricle. The postoperative course was complicated by persistent chylothorax, which was controlled by thoracic duct ligation, He was discharged to home at the postoperative day 39. He has been followed up for 9 months and has displayed normal development.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.639-643
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• 2004

[ $Ta_2O_5$ ]가 첨가된 $Ba(Zn_{1/3}Ta_{2/3})O_3$[BZT] 세라믹은 1:2 규칙화 정도가 증가하고 $Ba_3Ta_5O_{15}의 이차상이 새롭게 형성된다. $1580^{\circ}C$ 보다 높은 온도에서 소결된 BZT 세라믹은 $Ta_2O_5$를 첨가하면 입자의 성장이 일어나고 액상이 형성된다. 품질계수(Q) 값은 $1580^{\circ}C$ 보다 높은 온도에서 소결할 경우 미량의 $Ta_2O_5$ 첨가만으로도 상당히 증가한다. 상대밀도는 $Ta_2O_5$ 첨가량에 따라 감소하기 때문에 Q값의 증가는 상대밀도와는 무관하다. 반면에, $Ta_2O_5$의 첨가량에 따라 입자의 성장은 증가하였기 때문에 Q값의 향상은 입자크기와 관계가 있음을 알 수 있다. 많은 양의 $Ta_2O_5$ 첨가시 비록 입자 크기가 증가했음에도 불구하고 Q값이 매우 낮은 것을 볼 때, Q값의 감소는 $Ba_3Ta_5O_{15}$ 상의 영향과 낮은 밀도 값에 기인한 것이다.