• Journal of Forest and Environmental Science
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• 제30권1호
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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.

• 전자공학회논문지B
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• 제32B권12호
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• pp.1680-1686
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• 1995

GAs, effective stochastic search algorithms based on the model of natural evolution and genetics, have been successfully applied to various optimization problems. When population size is not large, GAs often suffer from the phenomenon of premature convergence in which all chromosomes in the population lose the diversity of genes before they find the optimal solution. In this paper, we propose that a new heuristic that maintains the diversity of genes by adding some chromosomes with random mutation and selective mutation into population during evolution. And population size changes dynamically with supplement of new chromosomes. Experimental results for several test functions show that when population size is rather small and the length of chromosome is not long, this method is effective.

• 복식문화연구
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• 제28권5호
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• pp.639-651
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• 2020

This study utilized data to classify and characterize the body types of plus-size adult men aged in their 30s and 40s. Diversity is an important factor in the era of inclusive design, and discussion about size diversity to include the plus size should be accommodated. Data from 493 adult men classified as obese (with a World Health Organization criterion ≥25 BMI) were used for the analysis. The results of the study are as follows. Six independent factors were extracted using factor analysis for cluster analysis, which were then classified into five types. Type 1 (29.01%) was identified as body type I with the smallest degree of obesity. Type 2 (15.4%) was identified as body type Y with wide shoulders and a thin waist. Type 3 (14.2%) was the largest body volume (body type O), while the fourth (19.27%) identified as body type H has a large height and upper body. Lastly, type 5 (22.11%) has a long lower body and a slim abdomen, referred to as body type X. This study presents a basis for the development of various clothing sizes utilizing the body shape characteristics of plus-size men in their 30s and 40s. Follow-up research is needed to develop patterns for plus size men and to design various products.

• 환경생물
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• 제21권4호
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• pp.337-341
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• 2003

Habitat heterogeneity can enhance biological diversity by providing variation in structural diversity. This paper reviewed heterogeneous habitat serves as a population stability and superior demographic performance (e.g., high density, survivorship, reproductive rate) can be observed compared with organisms with inferior demographic performance. The idea of habitat variation has been further developed in modelling. Furthermore the size and configuration (distribution) of a patch (of a particular habitat type) become effective for the stability of population through hiding places and food resources. Species diversity is related to habitat complexity that provides structural diversity to ground -dwelling organisms. Finally coarse woody debris can enhance habitat complexity thus stabilizing population fluctuation and increasing survivorship.

• 한국환경생태학회지
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• 제31권6호
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• pp.492-499
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• 2017

퉁퉁마디 개체군의 서식 면적에 따른 유전적 다양성을 조사하기 위하여 6개 군집 96개체를 대상으로 ISSR marker를 사용하여 분석하였다. 6개 ISSR 프라이머에서 총 49개의 PCR 증폭 밴드가 관찰되었으며 이 중 30개의 밴드가 유전적 다형성을 갖는 밴드로 나타났다. 퉁퉁마디 개체군 전체의 유전적 다양성을 나타내는 지수 I(Shannon's information index)는 0.382로 나타났으며 h(gene diversity)는 0.249으로 나타났다. 군집 크기에 따른 유전적 다양성 지수는 $0.1m{\times}0.1m$에서 0.092(I), 0.058(h)로 가장 낮게 나타났고 $25m{\times}25m$에서 0.338(I), 0.227(h)로 가장 높게 나타나 유전적 다양성이 높은 군집 형성에 적합한 면적이라 할 수 있다. 퉁퉁마디 개체군 간 거리에 따른 유전적 다양성의 상관관계를 UPGMA 방법으로 분석한 결과 퉁퉁마디 개체군 간 거리와는 유의한 상관관계를 보이지 않았다. 본 연구 결과 제한된 환경에서 서식하는 퉁퉁마디는 유전적 다양성을 갖는 군집 형성을 위해 일정한 크기 이상의 면적이 확보되어야 할 것으로 판단된다.

• Journal of Plant Biology
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• 제37권2호
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• pp.141-149
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• 1994

Levels of genetic diversity, population genetic structure, and gene flow in Hosta yingeri, a herbaceous perennial endemic to Taehuksan, Sohuksan, and Hong Islands, were investigated. Starch gel electrophoresis was conducted on leaves for 101 plants collected from three populations. Although the distribution of thespecies is restricted in the islands, it maintains high levels of genetic variatin; 64% of polymorphic loci in at least one population (Ps), the mean number of alleles per locus (Ap) of 1.92, and the mean effective number of alleles per locus (Aep) of 1.52. Overall, mean genetic diversity (Hep=0.250) was substantially higher than mean estimate for species with very similarlife history traits (0.102). Large populaton size, the persistence of multiple generations within populations, high fecundity, predominantly outcrossing breeding system, large size of pollinator visitation areas may be explanatory factors contributing the higher level of genetic diversity maintained within populations. Analysis of fixation indices showed an overall slight excess of heterozygotes (mean FIS=-0.066) relative to Hardy-Weinberg expectations, which may in part be due to the near self-incompatible breeding system in the species. Significant differences in allele frequencies among populaitns were found for 14 out of 16 polymorphic loci (P<0.05). Slightly more than 80% of the total variation in the species was common to all populations (GST=0.198). As expected, indirect estimate of the number of migrants per generation (Nm=0.45, calculated from mean GST) and nine private alleles found in the three populations indicate that gene movement among three isolated island populations was low.

• The Journal of Asian Finance, Economics and Business
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• 제7권3호
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• pp.87-99
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• 2020

The study aims to investigate factors that determine dividend payout policy using 336 non-financial firm year observations covering the period 2005 to 2016 in Malaysia. We found a significant positive relationship between corporate board size, board members average age, board tenure and dividend payout policy. We also found a strong negative effect and statistically insignificant relationship of board diversity, board independence, CEO duality and dividend payout policy. Additional, financial leverage has a negative effect on dividend payout policy. It is also noticed that firms with diverse boards are more likely to pay dividends and tend to pay larger dividends than those with non-diverse boards. Our results suggest that board diversity has a significant impact on dividend payout policy. Impact of board diversity on dividend payout policy is particularly conspicuous for firms with potentially greater agency problems. Our findings are consistent with the argument that corporate board traits enhancement positively affect the dividend payout policy which is beneficial for shareholders. This study offers useful insights into the current global debate on board traits and its implications for firms. The dividend payout policy signals good news to investors. Corporate board traits and firm's financial decision are the factors that disrupt the dividend decision.

• Asia pacific journal of information systems
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• 제29권2호
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• pp.203-216
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• 2019

There is an accuracy-diversity dilemma with personalized recommendation services. Some researchers believe that accurate recommendations might reinforce customer satisfaction. However, others claim that highly accurate recommendations and customer satisfaction are not always correlated. Thus, this study attempts to establish the causal factors that determine customer satisfaction with personalized recommendation services to reconcile these incompatible views. This paper employs statistical analyses of simulation to investigate an accuracy-diversity dilemma with personalized recommendation services. To this end, we develop a personalized recommendation system and measured accuracy, diversity, and customer satisfaction using a simulation method. The results show that accurate recommendations positively affected customer satisfaction, whereas diverse recommendations negatively affected customer satisfaction. Also, customer satisfaction was associated with the recommendation product size when neighborhood size was optimal in accuracy. Thus, these results offer insights into personalizing recommendation service providers. The providers must identify customers' preferences correctly and suggest more accurate recommendations. Furthermore, accuracy is not always improved as the number of product recommendation increases. Accordingly, providers must propose adequate number of product recommendation.

• 지능정보연구
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• 제16권1호
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• pp.93-116
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• 2010

불법현금융통 적발모형 개발에 앙상블 접근방법을 사용하였다. 불법현금융통은 국내 신용카드사의 손익에 영향을 미치며 최근 국제화되고 있음에도 불구하고 학문적인 접근이 이루어지지 않았다. 부정행위 적발모형(Fraud Detection Model, FDM)은 데이터 불균형 문제로 인하여 좋은 성능을 얻기 어려운데, 다수의 모형을 결합하는 앙상블이 대안으로 제시되어 왔다. 앙상블에 포함된 모형들의 다양성이 보장된다면 단일모형에 비해 더 좋은 성능을 보인다는 점은 이미 인정되고 있으며, 최근 연구 결과는 학습된 모든 기본모형들을 사용하는 것보다 적절한 기본모형들만 선택하여 앙상블에 포함시키는 것이 바람직하다는 것이다. 본 논문에서는 효과적인 불법현금융통 적발을 위하여 축소된 앙상블 기법을 사용하는데, 정확성과 다양성 척도를 사용하여 앙상블에 참여할 기본모형을 선택하는 것이다. 다양성은 앙상블을 구성하는 기본모형들 사이의 불일치 (Disagreement or Ambiguity)를 의미하는데, FDM에 내재된 데이터 불균형문제를 고려하여 두 가지 측면에 중점을 두었다. 첫째, 학습 자료의 추출 과정에서 다양성을 확보하기 위한 소수 범주의 과잉추출 방법과 적절한 훈련 방법에 대해 설명하였다. 둘째, 소수범주에 초점을 맞추어 기존의 다양성 척도를 효과적인 척도로 변형시키고, 전진추가법과 후진소거법의 동적 다양성 계산법을 도입하여 앙상블에 참여할 기본모형을 평가하였다. 실험에 사용된 학습 알고리즘은 신경망, 의사결정수와 로짓 회귀분석이었으며, 동질적 앙상블과 이질적 앙상블을 구성하여 성능평가를 하였다. 실험결과 불법현금융통 적발모형에 있어 축소된 앙상블은 모든 기본모형이 포함된 앙상블과 성능 차이가 없었다. 축소된 앙상블은 앙상블 구성의 복잡성을 감소시키고 구현을 용이하게 한다는 점에서 FDM에서도 유력한 모형 수립 접근방법이 될 수 있음을 보였다.

• 한국통신학회논문지
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• 제41권1호
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• pp.42-50
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• 2016

최근 LED 어레이와 카메라간의 통신 (일명, 'Visual-MIMO') 연구가 활발히 진행되고 있으며, 차량 및 스마트폰 등으로의 응용이 극대화될 것으로 기대된다. LED 어레이에서 ISI 정도가 심해지면 비트 판정에 오류가 발생하므로 다중화에서 다이버시티로의 전환이 필요하다. 본 논문에서는 참조 어레이 패턴의 사용 유무에 따라 각각 다이버시티로의 전환시점을 결정하기 위한 방법을 제시하고 검증한다. 참조 어레이 패턴을 사용할 경우에는 수신 영상의 휘도 정보를 이용하여 다중화에서 다이버시티 모드로의 전환 시점 결정한다. 참조 어레이 패턴을 사용하지 않을 경우에는 거리에 따른 전체 영상 대비 LED 어레이 영상의 크기를 이용한다. ISI가 심해지는 거리에서의 LED 어레이의 크기를 파악하여 다이버시티로의 전환시점 결정에 이용한다. LED간 ISI 정도 및 거리의 변화에 따라 제안한 방법의 성능을 분석하고 시뮬레이션과 하드웨어 실험을 통해 타당성을 검증한다.