• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.91-100
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• 2014

This research was conducted on the conservation area of Baekdudaegan, Kangwondo under the purpose of evaluating bio-diversity according to the changes of spatial scale, using GIS data and spatial filtering method. The diversity index was calculated based on the information of species of The $5^{th}$ forest type map using Shannon-weaver index (H'), evenness index ($E_i$) and richness index ($R_i$). The diversity index was analyzed and compared according to the changes of 12 spatial scales from Kernel size $3{\times}3$ to $73{\times}73$ and basin unit. As for H' and $R_i$, spatial scale increased as diversity index decreased, while $E_i$ decreases gradually. H' and $R_i$ was highest; each 1.1 and 0.6, when the Kernel size was $73{\times}73$, while $E_i$ was 0.2, the lowest. When you look at according to the basin unit, for large basin unit, 'YeongDong' region shows higher diversity index than 'YeongSeo' region. For middle basin unit, 'Gangneung Namdaecheon' region, and for small basin unit, 'Gangneung Namdaecheon' and 'Gangneung Ohbongdaem' region shows high diversity index. When you look at the relationship between diversity index and Geographic factors, H' shows positive relation to curvature and sunshine factor while shows negative to elevation, slope, hillshade, and wetness index. Also $E_i$ was similar to the relationship between H' and Geographic factor. Meanwhile, $R_i$ shows positive relationship to curvature and sunshine factor, while negative to elevation, slope, hillshade, and wetness index. macro unit diversity index evaluation was possible through the GIS data and spatial filtering, and it can be a good source for local biosphere conservation policy making.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.253-254
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• 2008

본 연구는 다중 안테나 배열 시스템을 응용한 고정 중계기가 적용된 상향 링크 셀룰러 환경에서 효과적으로 외곽 사용자의 QoS(Quality of Service)를 개선시키고 보다 높은 수준의 전체 데이터 전송률을 보장하는 기술을 제안한다.

• Journal of Communications and Networks
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• v.12 no.5
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• pp.442-448
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• 2010

Cooperative relaying methods have attracted a lot of interest in the past few years. A conventional cooperative relaying scheme has a source, a destination, and a single relay. This cooperative scheme can support one symbol transmission per time slot, and is caned full rate transmission. However, existing fun rate cooperative relay approaches provide asymmetrical gain for different transmitted symbols. In this paper, we propose a cooperative relaying scheme that is assisted with dual relays and provides full transmission rate with the same macro-diversity to each symbol. We also address equalization for the dual relay transmission system in addition to addressing the issues concerning the improvement of system performance in terms of optimal power allocations.

• Journal of Information Processing Systems
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• v.18 no.6
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• pp.803-812
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• 2022

With the increasing number of mobile device users worldwide, utilizing mobile edge computing (MEC) devices close to users for content caching can reduce transmission latency than receiving content from a server or cloud. However, because MEC has limited storage capacity, it is necessary to determine the content types and sizes to be cached. In this study, we investigate a caching strategy that increases the hit ratio from small base stations (SBSs) for mobile users in a heterogeneous network consisting of one macro base station (MBS) and multiple SBSs. If there are several SBSs that users can access, the hit ratio can be improved by reducing duplicate content and increasing the diversity of content in SBSs. We propose a Deep Q-Network (DQN)-based caching strategy that considers time-varying content popularity and content redundancy in multiple SBSs. Content is stored in the SBS in a divided form using maximum distance separable (MDS) codes to enhance the diversity of the content. Experiments in various environments show that the proposed caching strategy outperforms the other methods in terms of hit ratio.

• Ocean and Polar Research
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• v.25 no.4
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• pp.519-528
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• 2003

Species composition and community structure of marine benthic community were studied in the intertidal zone of Jijindo Island, Gwangyang Bay. A total of 85 species of benthic marine plants including the 5 Cyanophyta, 9 Chlorophyta, 13 Phaeophyta, 56 Rhodophyta and 2 Magnoliophyta that were listed. The community structure was represented by Gelidium divaricatum in the upper zone, Celidium divalicatum and Ulva pertusa in the middle, and Ulva pertusa, Chondria crassicaulis, Chondracanthus intermedia and Sargassum thunbergii in the lower intertidal zone. The dominant species in the rnscro-zoobenthic community were Chthamalux challengeri in the upper and middle, Littorina brevicula between the upper and middle, and Mytilus edulis and Crassostrea gigas in the middle and lower intertidal zones. The economic benthic organisms such as Undaria pinnatifida, Mytilus edulis, and Crassostrea gigas found in the lower intertidal zone were frequently disturbed due to their collection by local resident. Therefore, it is necessary to record the correct information pertaining to these cases. The species diversity indices estimated kom different sources were quite different. They were 2.22 derived from frequency, 1.67 based on coverage, 2.17 based on sum of frequency and coverage and 2.04 derived from importance value. Species diversity and number of algal species in Gwangyang Bay have noticeably decreased, compared with their previously reported status. It is estimated that their decreases were caused by changes in the marine environment, especially pertaining to the polychaete community resulting from reclamation and dredging activity undertaken for the industrial development.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.345-351
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• 2010

It has been growing interests that convergence services of broadcasting and telecommunication services such as DMB 2.0 and Mobile IPTV etc. Unicast type is difficult to service broadcasting due to limits of capacity and poor receiving environments, WiBro supports broadcast service with MBS. MBS is transmission method that base stations belong to same the MBS zone transmit the all users who request broadcasting service. Terminals are received resources from all base station in the MBS zone and SINR can be improved because of macro diversity. If terminals are located at edge of the MBS zone, complement algorithm are needed beacause received SINR is very low. In this paper, MIMO STBC, Relay and FFR are introduced to improve the throughputs using high MCS. The basic simulation environment is assumed to be SISO. Transparent relay and FFR applicable on MBS are divided by SISO and MIMO STBC environment and evaluate the performance.

• Journal of Environmental Science International
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• v.18 no.5
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• pp.561-567
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• 2009

The distribution of benthic macroinvertebrates of Shinbulsan wetland was investigated. This study was focused on the degree of recovery of habitat by comparing the community structure of benthic macro invertebrates of zone D to that of zone A, intact habitat. The zone D was destructed due to the construction of a golf club and the survey was performed in zone A and zone D of Shinbulsan wetland. The seasonal survey was performed in April, July and September from 2006 to 2007. From the sampling, 2 phyla, 3 classes, 9 orders, 31 families, 69 species and 1155 individuals of benthic macroinvertebrates were collected. From zone A, 2 phyla, 3 classes, 9 orders, 23 families, 54 species and 678 individuals were identified. From zone D, 2 phyla, 3 classes, 9 orders, 23 families, 43 species and 477 individuals were identified. Species diversity and species richness were higher in zone A than in zone D. The recovery of zone D was inefficient as humidity of soil was not enough to live macroinvertebrates. Also, an endangered species of macroinvertebrates, Nannophya pygmaea was found during this investigation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.6
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• pp.173-189
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• 2023

As supreme technologies continue to be developed, industries such as artificial intelligence, biotechnology, robots, aerospace, electric vehicles, and solar energy are created, and the macro business environment is rapidly changing. Due to these large-scale changes and increased complexity, it is necessary to pay attention to the effect of social capital, which can create new value by utilizing capital increasing the importance of relationships rather than technology or asset ownership itself at the level of start-up strategy. Social capital is a concept first proposed by Hanifan in 1916, and refers to the overall sum of capabilities or resources that are latent or available for use in mutual, continuous, organic relationships or accumulated human relationship networks between individuals or social members. In addition, the diversity of start-up teams with diverse backgrounds, characteristics, and capabilities, rather than one exceptional founder, has been emphasized. Founding team diversity refers to the diversity of in-depth factors such as demographic factors, beliefs, and values of the founding team. In addition, changes in the macro environment are emphasizing the importance of technology start-ups and laboratory start-ups that lead industrial innovation and create the nation's core growth engines. This study focused on the I-Corps' program. I-Corps, which means innovation corps, is a laboratory startup program launched by the National Research Foundation (NSF) in 2011 to encourage entrepreneurship and commercialization of research results. It focuses on forming a startup team involving professors, researchers and market discovery activities. Taking these characteristics into account, this study empirically verified the impact of social capital from a network perspective and founding team diversity on I-Corps start-up performance. As a result of the analysis, the educational diversity of the founding team had a negative (-) effect on the financial performance of the founding team. On the other side, the gender diversity and the cognitive dimension of social capital had a positive (+) effect on the financial performance of the founding team. This study is expected to provide more useful theoretical and practical implications regarding the diversity, social capital, and performance interpretation of the I-Corps Lab startup team.

• Journal of Environmental Impact Assessment
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• v.15 no.4
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• pp.279-288
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• 2006

Saemangeum reclamation project was started in 1991 with the purpose of eco-friendly reclamation, but without clear definition of eco-friendliness. This study was carried out to find out the environmental indicators to define and evaluate the eco-friendliness of Saemangeum project. The methodology to identify the indicators included the analysis of similar reclamation projects, professional discussions, and Delphi survey. The eco-friendly indicators are theoretically based on the five elements of eco-friendliness; 1) resource consumption, 2) energy consumption, 3) pollution emission, 4) bio-diversity, 5) social amenity. The 69 indicators were explained in detail for the convenient use of the indicators by the potential users. The 69 indicators were classified into three categories such as pre-evaluation, process evaluation, and post-evaluation. In terms of spatial consideration, the 69 indicators were classified into two categories such as direct influence area and indirect influence area. Also the 69 indicators were classified into 7 categories: 1) sea, 2) lake, 3) agricultural land use, 4) industrial land use, 5) residential land use, 6) tourism land use, and 7) environmental land use. Twenty core indicators were selected from the 69 indicators by surveying the importance of each indicator. The core indicators are recommended in case of time and budget strain. When there are few quantitative data accumulated for the reclamation project, 5 macro indicators are recommended to be used. Macro indicators are qualitative in nature, and may be used in order to evaluate the overall eco-friendliness of a reclamation project.

• 한국해양학회지
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• v.13 no.2
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• pp.31-41
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• 1978

The planktonic algal communities of the Han River with a particular emphasis on water pollution was studied over a twelve month of period. Results of observing many algal communities from 7 stations of the Han River have shown that these communities are generally composed of many species, most of which have relatively small populations with a few exceptional dominant species. The distribution of the total standing crop of phytoplankton in the studid area is characteristic, summer in the polluted zone. Diversity indices of all samples were computed and have shown that the H values of 7 stations are relatively low. However, a detailed examination of these H values reveals that the seasonal fluctuations of the species diversity remarkably coincide with those fo phytoplankton standing crop.No reduction in the species diversity at stations 4, 5, 6, and 7 where the water is heavily polluted indicates that a great number of species capable of invading stations, 4, 5, and 6 from the various tributaries, and the station 7 from the contaminated with sea water are probably more important in the functional changes of the communities than the size of sampling area. It is evident that the diversity index in a lotic environment does not indicate water quality as far as phytoplankton communities are concerned.