• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.7
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• pp.1036-1043
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• 1993

GaAs/AIGaAs resonant tunneling structures have been grown by atmospheric pressure MOCVD. Resonant tunneling diodes fabricated with the structure grown at 650t showed a high peak-to-valley (P/V) current ratio of 2.35 at room temperature. P/V current ratio increased to 15.3 at 77K. Numerically calculated peak current agrees well with the experimental result. Resonant tunneling diodes with AIGaAs as a barrier and InGaAs as a quantum well and a spacer layer yielded a high P/V current ratio of 4.0 and a peak current density of 8.6KA/c# at room temperature because of increased carrier supply.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.3
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• pp.281-288
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• 2004

The objective of this study is to propose a methodology of the flood runoff analysis in steep mountainous basins and the analysis basin is the Jasa valley basin in Chungju city Analyzing the spatial pattern of the rainfall in 1994. 6 30~7.1, the seasonal rainy front was tied up in the whole central district, and the rainfall center was moving from the northern Chungbuk province to the northern Kyongbuk province and caused heavy storm. Analyzing the temporal pattern with the Huff method, the 52.5% of the rainfall was concentrated on the 3rd quartile. Rainfall frequency analysis is accomplished by five distribution types; 2-parameter Lognomal, 3-parameter Lognomal, Pearson Type III, Log-Pearson Type III and Extremal Type I distribution Rainfall-runoff analysis in Jasa valley basin was made using HEC-HMS model. Jasa valley basin was divided into 3 sub-basins and the analysis point was 3 points{A, B and C point) With the rainfall data measured by the 10 minutes, the flood runoff also was calculated by as many minutes. SCS CN model, Clark UH model and Muskingum routing model in HEC-HMS model were used to simulate the runoff volume using selected rainfall event.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.277-281
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• 2003

Amplified fragment length polymorphism (AFLPs) markers were used to investigate the genetic variation in six autochthonous goat populations distributed in the middle and lower Yangtze River valley. The goat populations were Chengdu Grey Goat (CGG), Chuandong White Goat (CWG), Banjiao Goat (BG), Matou Goat (MG), Hui Goat (HG) and Yangtze River Delta White Goat (YRDWG). A total of 180 individuals (30 per population) were analysed using ten selected AFLP primer combinations that produced 78 clear polymorphism loci. The variability at AFLP loci was largely maintained within populations, as indicated by the average genetic similarity, and they were ranged from 0.745 to 0.758 within populations and 0.951 to 0.970 between populations. No breed specific markers were identified. Cluster analysis based on Nei' genetic distance between populations indicated that Chengdu Grey Goat is the most distant population, while CWG and YROWG were the closest populations, followed by BG, HG and MG. Genetic diversity of the goat populations didn' confirm what was expected on the basis of their geographical location, which may reflect undocumented migrations and gene flows and identify an original genetic resource.

• Journal of Information Technology Services
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• v.12 no.1
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• pp.143-161
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• 2013

Convergence is now the trend of knowledge information society. Information technology and knowledge transfer are main sources of convergence. There are many articles which studied outcomes of convergence while there are few articles that try to study the process of convergence. The purpose of this study is to investigate how convergence is dynamically formalized. For the analysis, we used Institutional Analysis and Development(IAD) framework from the point of convergence. IAD framework could synthetically study the origin and the process of convergence. We investigated the case of sillicon valley whether or not dynamics of ICT convergence could be explicable by IAD framework. The results shows that ICT technology and knowledge could be the enabler for the formation of convergence. ICT technology accelerates convergence and knowledge convergence from information converge different technologies and industries. This article provides a theoretical foundation for future research to analyze dynamics of ICT convergence by the IAD framework. For the future work, it is recommended that a study is to be empirically analyzed the dynamics of ICT convergence.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.27-33
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• 2011

Hemp bast pulp cooked at temperature below $100^{\circ}C$ followed by defibration by the knife and the valley beater, respectively was mixed with softwood pulp varying the amount of hemp pulp in order to find the optimum condition for making hemp-wood paper. Both the knife and the valley beaters contributed to the dispersion of pulp fiber well. Lots of shives were found when the knife beater was applied exclusively, but the fibers were dispersed well when freeness dropped to 600 mL CSF and 500 mL CSF by the valley beater. Air resistance decreased drastically below 500 mL CSF where rapid disrupture of pulp fiber occurred. As the values for freeness and hemp fiber content increased, so did roughness and bulk. It was apparent that the tear strength of hemp-wood paper was on the rise drastically as hemp fiber content increased. Nevertheless the optimum hemp fiber content of hemp-wood paper would be 20% considering the decrease in both tensile and burst strengths as well as sheet formation.

• Journal of Species Research
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• v.6 no.1
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• pp.76-90
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• 2017

Aster altaicus var. uchiyamae Kitam. is an endemic taxon of Korea and is protected by law as an endanger taxon. The genetic information of A. altaicus var. uchiyamae is unavailable in Genbank. Here we sequenced chloroplast genome of A. altaicus var. uchiyamae. The cp-genome of Aster altaicus var. uchiyamae was 152,446 bps in size: LSC was 84,240 bps, IR 25,005 bps, SSC 18,196 bps. The cp-genome contains 112 genes and 21 introns consisted of 79 protein coding genes(PCGs), 4 RNA genes, and 29 tRNA genes, with 20 group II introns and one group I intron. There were three pseudo-genes including ${\psi}$-ycf1, ${\psi}$-rps19, and ${\psi}$-trnT_GGU. Eighteen genes, five introns, and parts of two genes and an intron are found within the IR, which has two copies. The cp-DNA of Aster altaicus var. uchiyamae is distinguished from A. spathulifolius, only known cp-genome of the genus Aster, by 172 SNP in genic regions of 43 PCGs and 21 indels in 11 PCGs and SSU. The chloroplast genome sequence was deposited at GenBank (KX35265).

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.107-120
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• 1995

To investigate the forest structure of Chuwang valley of Chuwangsan National Park, thirty plots were set up and surveyed. Importance values, DBH class distribution, species diversity indices, DCA Ordination, CCA ordiantion and TWINSPAN classification were used for vegetational structure analysis. Pinus densiflora Quercus serata, Q. mongolica, Q. variabilis were appeared to be dominant species in thirty plots. According to the analysis of classification by TWINSPAN, the thirty plots divided four groups. Groups were Q. mongolica-P. densiflora-Carpinus laxiflora community(I), P. densiflora-Q. variabilis community(II), Q. serrata-Q. variabilis community(III), broad-leaved mixed community(IV) Species diversity(H') of investigated area was calculated 1.17~l.32. The successional trend was seemed to be from P. densiflora to Q. spp. in the canopy layer.

• Korean Journal of Environment and Ecology
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• v.10 no.2
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• pp.283-296
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• 1997

To investigate the plant community structure in valley and suggest the management of Mational Park, fifty plots were set up and surveyed in Jujeongol Valley, Soraksan National Park. The classification by TWINSPAN and DCA ordination technique were applied to the study area in order to classify them into several groups based on woody plants. The dividing groups were Quercus mpnngolica - Q. variabilis - Pinus densiflora community, P. densiflora community, Carpinus laxiflora community, Q. serrata community. The ecological trends of tree species by DCA ordination technique and DBH class distribution analysis was like that Q. mongolica - Q. variabilis - P. densiflora community and P. densiflora community seems to be trended from P. densiflora community to Q. mongolica community. Q. serrata community seems to be trended from Q. serrata community to C. laxiflora community and C. laxiflora will be maintaimed stable state.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.507-517
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• 1996

To explain the horizontal expansion of a rhizomatous perennial, Convallaria keiskei(lily-of-the-valley), in a study site of Chunchon, Kangwon Province, Korea, ramet growth and clonal structure were studied. Remarkable growth stategies were clarified. First, the timing for the successive phenological events such as sprouting. flowering and rhizome growth for lily-of-the-valley was fitted to exploit early spring when the canopy of overstory was opened. Second, these events were supported by effective matter allocation pattern: for example, two-year investment for new rhizomes enabled the first year ramets to mature in six weeks after sprouting and to grow up to 85% of the leaf area of perennial ramets. Finally, the ramet population was increased by local disturbances such as freezing, herbivory and collection by human. The rule that a clone was supposed to produce one new thizome per year was broken by occasional disturbances. Then, up to 5rhizomes from latent bur could be redeveloped. Based on clonal structure, 80% or total clones have from 1 to 4 ramets. this means there have occurred minor disturbances. Therefore, in conclusion, the successful flourishing of lily-of-the-valley came from its effective frowth strategy to take advantage of site disturbance.

• World Technopolis Review
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• v.6 no.1
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• pp.5.1-5.12
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• 2017

The Republic of Korea developed a national project to construct a new administrative capital, Sejong city and to relocate administrative organizations of the central government for improvement of overpopulated capital, Seoul and regional balanced development. By the way, to relocate the central administrative organizations was not a sufficient condition for the sustainable development of the city. An industrial infrastructure development has been tried to attract universities, enterprises and research institutions in the region as a demand for internal growth power of the city was increased. In addtion, a basis for regional endogenous growth through projects to establish innovation system based on industry-academia cooperation was prepared as well. This paper reviews the major contents of the development plans for Tech-Valley project and looks into major introductory functions, characterization plans, strategies for fostering strategic industry, cooperation system of the inside and outside the region, and a strategy for building innovation platform. This case can be regarded as a significance of constructing technology infrastructure for the sustainable growth by preparing foundation for establishing innovation system and a cluster based on this system in the process of building and developing new city which did not have any industrial platform in the region.