• The Korean Journal of Ecology
• /
• 제17권4호
• /
• pp.453-461
• /
• 1994

Size class structure and vegetative growth of a perennial herb of the temperate deciduous forests, Symplocarpus renifolius Schott, were studied from 1991 to 1994 in Namhansansung, Kyonggi Province, Korea. The size class structures of leaf number and leaf area per individual followed bell-shape curve, i.e. frequency of middle class was relatively high. The leaf area increased from the late-March to mid-May. At the end of the growing season, leaf area(length X breadth) was proportional to biomass, especially aboveground biomass. The leaf number and leaf area per individual increased at the rate of 0.08 leaf/year and 9.7 $cm^2/year$, respectively. The size of the individuals in large-sized classes, in leaf number and leaf area, decreased in next year, while the size of the individuals in small-sized classes increased. Therefore, it was concluded that the size class structure of S. renifolius population was largely determined by the growth form.

• 한국정보시스템학회지:정보시스템연구
• /
• 제26권1호
• /
• pp.1-19
• /
• 2017

연구목적 본 연구는 크라우드펀딩 맥락에서 개인 및 국가 수준의 사회적 자본이 창업 활동에 미치는 영향에 대해 분석하고자 한다. 연구설계/방법론/접근법 본 연구는 두 가지 주요한 자료원을 활용했다. 먼저 미국의 대표적인 크라우드펀딩 플랫폼인 킥스타터(Kickstarter)에서 15,716개의 크라우드펀딩 프로젝트 및 개인 수준의 사회적 자본 관련 자료를 수집하는 한편 레카툼 번영지수(Legatum Prosperity Index)를 참조하여 국가 수준의 사회적 자본 관련 자료를 수집했다. 크라우드펀딩 프로젝트별로 개인 및 국가 수준의 사회적 자본을 측정한 후 사회적 자본이 창업 활동에 미치는 영향에 대해 포아송 회귀분석 및 음이항 회귀분석을 실시했다. 결과 분석결과에 따르면 페이스북 친구수, 다른 프로젝트 후원 횟수, 프로젝트 소개글 수 등 창업가 개인 수준의 사회적 자본은 크라우드펀딩내 창업 활동과 긍정적으로 유의한 관계에 있는 것으로 나타났다. 또한 국가별 사회적 자본 지수로 측정한 국가 수준의 사회적 자본도 크라우드펀딩내 창업 활동과 긍정적으로 유의하게 나타났다.

• 한국IT서비스학회지
• /
• 제13권3호
• /
• pp.201-219
• /
• 2014

This paper considers service deployment and priority optimization for multiple service-oriented applications sharing reusable services, which are deployed as multiple instances in the cloud. In order to handle variations in the workloads of the multiple applications, service instances of the individual reusable services are dynamically provisioned in the cloud. Also service priorities for each application in a particular reusable service are dynamically adjusted. In this paper, we propose an analytic performance model, based on a queueing network model, to predict the expected sojourn times of multiple service-oriented applications, given the number of service instances and priority disciplines in individual reusable services. We also propose a simple heuristic algorithm to search an optimal number of service instances in the cloud and service priority disciplines for each application in individual reusable services. A numerical example is also presented to demonstrate the applicability of the proposed performance model and algorithm to the proposed optimal decision problem.

• 상하수도학회지
• /
• 제24권1호
• /
• pp.33-40
• /
• 2010

Individual sewage treatment system is classified into a sewage treatment system which treats all the domestic sewage and a water-purifier tank which treats only effluent flushing from the toilet. The number of registered manufacturers has increased rapidly since 2001. As a result, price competition has increased among the manufacturers and has caused the problems such as the inappropriate production of individual sewage treatment system, the unreasonable permit for building completion and the shortage of the professional technology of the community's public officials in charge. This study collected the problem cases that are related with existing individual sewage treatment system and operation. Efficient improvement plan for the stable supply, installation, maintenance of individual sewage treatment system were suggested.

• Animal cells and systems
• /
• 제3권1호
• /
• pp.29-39
• /
• 1999

Current data on reproductive characters of endemic and native species are essential to provide a strategy for the conservation of these species. Red pine (Pinus densiflora Sieb. & Zucc.) is one of the dominant, native tree species in Korea, but its reproductive ecology is not well-known. In 1997, the pattern of variation in cone and seed yields contributing to the conservation of declining populations of red pines was examined. Plant height and dbh were measured, and several new cones were collected from each tagged tree after counting the number of cones on each tree. For a subset of cones sampled, the number of fertile scales, the number of seeds at three development stages (early/late aborted, and filled seed), seed wing size, wing color, and individual filled seed mass were measured. The three sites which differed significantly in mean plant size also differed in mean cone and seed production per plant. However further analyses showed that most variation in characters examined occurred among plants within sites, but not among sites. An average of 90% of the potential seeds on the cones aborted at an early developmental stage, demonstrating that early abortion is a major factor affecting the number of filled seeds per cone. Individual seed mass was the only character which exhibited significant variations among sites as well as among trees within sites. Individual seed mass was overall negatively correlated with both the percentage of late abortion and the number of old cones per plant, suggesting that both the past and current years' reproductive activities have caused variations in seed mass. The potential dispersal distance of red pine seeds is quite large. However, wing loading was correlated with seed mass and number in a complex pattern across the sites. Distribution of seeds with varied colored wings differed among sites and among trees within sites. These results suggest that red pines at different sites might possess different strategies to cope with selection pressures acting during the final phase of reproduction, from seed dispersal to establishment. Then the ‘fitted’ red pine trees at each site should be identified and managed to conserve or restore populations.

• 간호행정학회지
• /
• 제5권3호
• /
• pp.463-475
• /
• 1999

This study investigated the relationship between nurses' Career Commitment and Organizational Commitment, and the moderating effect of individual career-related characteristics (age, tenure, position, number of department change, number of hospital change) on the relationship between career commitment and organizational commitment. The sample for this study consisted of 594 nurses from 8 large Korean hospitals. And the factor analysis, Cronbach's alpha, multiple regression analysis and two-way ANOVA were used for the statistical methods. Research was found that (1) career commitment and the two dimensions of organizational commitment(affective and transactional) were validated as distinct concepts for Korean nurses. (2) career commitment showed positive influence on the two dimension of organizational commitment, (3) all individual career-related characteristics did not moderated the effect of career commitment on affective commitment, but (4) number of career department change and of hospital change among career-related characteristics moderated the effect of career commitment on transactional commitment. Theoretical and practical implication of these result were discussed in the conclusion.

• 한국환경생태학회지
• /
• 제12권4호
• /
• pp.361-372
• /
• 1999

한려해상국립공원내 거제도지구 곰솔-소나무림의 식물군집구조와 분포밀도를 규명하기 위해 32개 조사구(10m$\times$10m)를 설정하였다 DCA분석 결과 곰솔군집, 곰솔-소나무군집, 소나무군집으로 분리되었고, 각 군집의 천이경향은 불명확하였다. 조사구별 교목층의 곰솔과 소나무의 분포밀도 현황에 대해 단순회귀분석을 실시한 결과는 다음과 같았다. 분포거리 (m) = 0.094$\times$흉고직경 (cm)-0.1248, 개체수=1,820.1$\times$흉고직경 $(cm)<^{-1.6734}$ , 분포거리 (m) = 6.6805$\times$$개체수^{-0.5425}$

• Journal of Biosystems Engineering
• /
• 제24권3호
• /
• pp.225-234
• /
• 1999

This study was performed as a basic research for establishing an objective quality evaluation method on whole bulbs of garlic. The size of a whole bulb of garlic, the number and the uniformity of complete individual garlics, and the existence of bad individual garlics in the whole bulb of garlic were selected as quality grading factors. Quality discrimination algorithms with machine vision techniques were developed and verified for the four factors based on morphological and physical features of whole bulbs of garlic. Based on the results, the size discrimination by the projected area of a whole bulbs of garlic suggested four grading levels and the algorithm for predicting the number of complete individual garlics based on the peaks on its projected boundary showed ${\pm}$0.78 prediction error. In addition, the uniformity represented by coefficient of variation could be divided into four levels, but the algorithm for discriminating the existence of bad individual garlics in a whole bulb of garlic was not effective.

• 한국환경복원기술학회지
• /
• 제21권4호
• /
• pp.65-73
• /
• 2018

Although the road construction in forest is increasing and there is a need for development ecological restoration on deforest area, no consideration has been given to individual trees in there. This study analyzed aerial photographs of deforest area before and after road construction for determining the degree of forest destruction by extracting individual trees. Study area was selected in the sites where are damaged by road construction in GongJu-si, YuSung-gu, and YeongDong-gun. The aerial photograph taken 1979 before construction is panchromatic image of 80cm in GSD (Ground Sample Distance) and other photograph taken 2016 after construction is multi-spectral image of 10cm in GSD. In order to minimize the difference of GSD, we conducted image re-sampling process for setting to same GSD for the two photographs. After that we carried out visual interpretation method for determining to change of individual tree. The result found that for GongJu-si of the number of individual tree was 1,014 in 1979 and 886 in 2016, which decreased by 128 (12.6%) and the average width of those decreased from 5.77m to 5.75m by 0.47%. In case of YoungDong-gun, the number of it was 761 in 1979 and 746 in 2016, which decreased by 2.0% and the average width of it decreased from 8.99mm to 8.90m by 1.1%. Lastly in case of YuSung-gu, the number of it was 1,578 in 1979 and 988 in 2016, which decreased by 37.4% and the average width of it decreased from 7.09m to 6.65m by 6.21%. these result imply that road construction causes destruction of forests. Since there are limitations such as errors due to researcher, it is necessary to construct a quantitative analysis method for the change of the deforest area. It is need to study the method of extracting individual tree in deforest area more accurately using high-resolution image of GSD 10cm or more as well. This study can be used as a basic data for the ecological restoration of the deforest area considering characteristics of individual tree such as height, diameter at breast height, and biomass.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1999년도 전력전자학술대회 논문집
• /
• pp.354-357
• /
• 1999

This paper is proposed Single phase Multi-Level AC-DC Converter. This is consist of diode bridge and switches. The number of the supply current levels depends on the number of the individual converter's current level. In this converter circuit the number of the levels is equal to 2(M+1) -1, where M is the number of Switching-Leg's number. In this paper is introduced converter with 31 current Level. If the number of current level is increased, smoother sinusoidal waveform can be obtained. The feasibility of the circuit is verified by computer simulation using PSIM