• Title/Summary/Keyword: Distribution Patterns

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Potential Impact of Climate Change on Distribution of Warm Temperate Evergreen Broad-leaved Trees in the Korean Peninsula (기후변화에 따른 한반도 난대성 상록활엽수 잠재서식지 분포 변화)

  • Park, Seon Uk;Koo, Kyung Ah;Kong, Woo-Seok
    • Journal of the Korean Geographical Society
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    • v.51 no.2
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    • pp.201-217
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    • 2016
  • We accessed the climate change effects on the distributions of warm-evergreen broad-leaved trees (shorten to warm-evergreens below) in the Korean Peninsula (KP). For this, we first selected nine warm-evergreens with the northern distribution limits at mid-coastal areas of KP and climate variables, coldest month mean temperature and coldest quarter precipitation, known to be important for warm-evergreens growth and survival. Next, species distribution models (SDMs) were constructed with generalized additive model (GAM) algorithm for each warm-evergreen. SDMs projected the potential geographical distributions of warm evergreens under current and future climate conditions in associations with land uses. The nine species were categorized into three groups (mid-coastal, southwest-coastal, and southeast-inland) based on their current spatial patterns. The effects of climate change and land uses on the distributions depend on the current spatial patterns. As considering land uses, the potential current habitats of all warm-evergreens decrease over 60%, showing the highest reduction rate for the Kyungsang-inland group. SDMs forecasted the expansion of potential habitats for all warm-evergreens under climate changes projected for 2050 and 2070. However, the expansion patterns were different among three groups. The spatial patterns of projected coldest quarter precipitation in 2050 and 2070 could account for such differences.

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The Spatial Characteristics of Clinic Distribution by Specialty Subject (진료 전문과목별 개원 의원의 공간적 분포 특성)

  • Seo, Wee-Yeun;Lee, Keum-Sook
    • Journal of the Economic Geographical Society of Korea
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    • v.10 no.2
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    • pp.153-166
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    • 2007
  • This study attempts to investigate the spatial characteristics of medical hospital distributions in Korea. For the purpose we examine the inter- and intra regional variations in the distributions of clinics by specialty subject. In particular, we analyze the distribution patterns of Location Quotients of clinics for 12 specialty subjects in Seoul. Medical services tend to be concentrated on the large cities, especially in the Metropolitan Seoul Area. In particular, clinics and medical doctors as well as large scale general hospitals have been strongly concentrated on the Metropolitan Seoul area. These circumstace may be related with the fact that medical hospitals are established and operated by private sector in Korea, and thus they attempt to find their location where they can get maximum profit. The distribution patterns of clinics of 12 specialty subjects can be classified to several characteristic patterns. In particular, clinics of plastic surgeon tend to be strongly concentrated on the Gangnam area in Seoul. Finally, clinics of plastic surgeon tend to be located on the areas near the subway stations along the subway Line 2 and Line 3 in the beginning. The existence of plastic surgeons turns out to have significant role on determining the location for the newly opening plastic surgeons in the later. Therefore, their agglomeration has been getting more strongly.

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A study on size variation of micro-pattern according to turning radius of workpiece in diamond turning with controlled random cutting depth (절삭 깊이의 무작위 제어를 적용한 다이아몬드 선삭공정에서 소재회전 반경에 따른 미세패턴의 크기변화 분석 연구)

  • Jeong, Ji-Young;Han, Jun-Se;Choi, Doo-Sun;Je, Tae-Jin
    • Design & Manufacturing
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    • v.14 no.1
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    • pp.63-68
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    • 2020
  • Ultra-high brightness and thin displays need to optical micro-patterns which can uniformly diffuse the lights and low loss. The micro random patterns have characteristics to rise the optical efficiency such as light extraction, uniform diffusion. For this reason, various fabrication processes are studied for random patterns. In this study, the micro random patterns were machined by diamond turning which used a controlled cutting tool path with random cutting depth. The machined patterns had random shape and directionality along the circumferential direction. The average width and length of machined random pattern according to rotation radius were 40.13㎛~55.51㎛ and 37.25㎛~59.49㎛, and these results were compared with the designed result. Also, the machining error according to rotation radius in diamond turning using randomly controlled cutting depth was discussed.

Response Patterns of Nursing Unit Managers regarding Workplace Bullying: A Q Methodology Approach (직장 내 괴롭힘에 대한 간호단위 관리자의 대응 양상: Q 방법론적 접근)

  • Choi, Jin Kyu;Lee, Byoungsook
    • Journal of Korean Academy of Nursing
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    • v.49 no.5
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    • pp.562-574
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    • 2019
  • Purpose: The purpose of this study was to identify the response patterns of nursing unit managers regarding workplace bullying. Methods: Q methodology was used to identify the response patterns. Thirty-six Q samples were selected from the Q population of 210 that included literature reviews and in-depth interviews with clinical nurses and nursing managers. Participants were 30 nursing unit managers who had experience managing workplace bullying and they classified the Q samples into a normal distribution frame measured on a nine-point scale. The data were analyzed using the PC-QUANL program. Results: Five types of response patterns were identified: (1) sympathetic-understanding acceleration, (2) harmonious-team approach, (3) preventive-organizational management, (4) passive observation, and (5) leading-active intervention. The preventive-organizational management type was most frequently used by the nursing unit managers. Conclusion: The results of this study indicated that nursing unit managers attempted to prevent and solve workplace bullying in various ways. Therefore, it is necessary to develop and conduct leadership training and intervention programs that appropriately address the response patterns of nursing unit managers, such as those identified in this study.

Spatial-temporal distribution of carabid beetles in wetlands

  • Do, Yu-No;Jo, Hyun-Bin;Kang, Ji-Hoon;Joo, Gea-Jae
    • Journal of Ecology and Environment
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    • v.35 no.1
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    • pp.51-58
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    • 2012
  • In this study, we investigated carabid beetles residing in the wetlands to understand their ecological adaptation and strategy selection associated with restricted resources and habitat limitation. The species richness, abundance, seasonal activity, and spatial distribution of the carabid beetles between the Mujechi Wetlands (wetland sites) and Mt. Jeongjok (mountain sites) have been compared. A total of 1,733 individual beetles from 30 species were collected and classified at the studied sites. The wetland sites were identified as having lower species richness and abundance for carabid beetles when compared with the adjacent mountain sites, whereas these beetles were observed to be dominant in the wetland sites than in the adjacent mountain sites. Calosoma inquisitor cyanescens, Carabus sternbergi sternbergi, and Carabus jankowskii jankowskii species were dominant in both the wetland and mountain sites. These species showed significantly different seasonal activity patterns in the wetland sites relative to the mountain sites. Although the three listed carabid species were observed to be widely distributed throughout the wetland sites, they still showed preference for drier sites, which clearly shows a distinction in their habitats. The results of the spatial-temporal distribution of carabid beetles in the wetland sites reflect their special strategies regarding space and time partitioning for maintaining their population. The distribution patterns of carabid beetles in the wetland sites also showed the desiccation gradient and environmental changes prevalent in wetlands. Ecological surveys, which use carabid beetles in the wetlands, can then be performed when restoring wetlands and for establishing management practices for improving the habitat quality.

The Analysis of Atmospheric Flow Field and Air Quality According to the High Level Ozone Case on Gwangyang Bay (광양만 권역에서의 고농도 오존 사례에 대한 기상 및 대기질 분석)

  • Choi, Hyun-Jung;Lee, Hwa-Woon;Leem, Heon-Ho;Song, Jae-Hwal
    • Journal of Environmental Science International
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    • v.17 no.7
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    • pp.743-753
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    • 2008
  • Gwangyang Bay is often severely confronted by photochemical pollutants due to its location and dense emissions. It is located in a basin on the south coast of the Korean peninsula and is crossed by a remarkable cluster of hills and mountains of a small horizontal scale that forms a channel. Clearly, the air flow field has a great influence on the dispersion of air pollutants. The characteristics of the wind flow patterns have an important effect on the dispersion of pollutants emitted. In these situations, the distribution of the ozone concentration is extremely complicated because of the superposition of circulations of the air flow fields, especially in complex coastal region. In this study, we examined the distribution of the high level ozone on Gwangyang Bay particularly during the episode day (for 5 years). Among these days, A high level ozone was induced by the development of a sea/land breeze local circulation system, as well as by an anabatic/catabatic flow from the mountains and valley with weakening of the synoptic wind. High level ozone distribution pattern(6 types) on Gwangyang bay is analyzed and the comparison of each pattern reveals substantial localized differences in intensity and distribution of ozone concentration from the site coherence and UPA analysis of ozone concentration. The observed VOC concentration had much difference in concentrations and daily variations between Jungdong and Samil.

Spatial distribution patterns of the surficial sediments in the tidal river, Gongneungcheon (공릉천 감조구간에 나타나는 표층퇴적물의 공간적 분포 특성)

  • CHOI, Yeoung Seon
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.4
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    • pp.203-212
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    • 2011
  • The objective of this paper is to identify the present-day surficial sediment distribution patterns of the tidal river, Gongneungcheon, through the grain size and statistical analysis. Four major findings of this study are as follows; First, the composition of sediments over the study area are mainly silt in texture. Second, the surficial sediment distribution reveals that grain size becomes coarser as they approach seawards not only in summer but also in winter. It can be concluded that tidal flows play a significant role, especially in winter, in the distribution of surficial sediments in Gongneungcheon. However, samples obtained in summer were relatively small in mean size and showed better sorting compared to those obtained in winter. Third, the mean sizes of the samples on the transects decrease as the distance from the channel increases. Finally, the artificial structure such as a floodgate affects the distribution of the sediments.

Changes of Total Gaseous Mercury Concentration Levels and the Associated Environmental Conditions in Seoul, Korea (12년 차이를 두고 본 서울 한남동 지역 대기 중 수은의 분포특성과 환경요인의 비교)

  • Kim, Min-Young;Kim, Ki-Hyun
    • Journal of the Korean earth science society
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    • v.22 no.3
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    • pp.237-247
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    • 2001
  • The concentrations of gaseous mercury (Hg) determined between two different time periods of the late 1980s and the late 1990s were compared to account for the effects of changes between source/sink relationships of atmospheric Hg in an urban area. The Hg concentration levels were different remarkably between the two time periods due possibly to changes in source/sink relationships. The results showed that the Hg levels in the former period were measured to be 14.4${\pm}$9.56ngm$^{-3}$ (N = 2714), whereas those of the latter period were characterized by approximately three-fold decreased values of 5.34${\pm}$3.92 ngm$^{-3}$ (N=2576). Using two independent measurement data sets, we examined the patterns of Hg distribution at different time scales. When analyzed over 24 hour scale, these data sets exhibited two distinctive distribution patterns. The former period showed enhanced concentration levels during daytime, while the latter period showed relative depletion during daytime. The patterns of the two data sets were also examined over seasonal scale. The results of two different time periods consistently showed the occurrences of maximum seasonal values during winter. The former period was characterized by seasonal patterns of fuel consumption with excessive Hg levels during winter. Conversely, no distinctive trend was apparent for the latter period with slight changes in concentration levels across seasons. In order to analyze the factors affecting Hg distributions between two different periods, we conducted both correlation and factor analysis on both all data sets and on seasonally divided data groups. The results of these analyses consistently indicate that the Hg concentration levels for two different time periods are regulated by distinctive source processes that are characteristic of each period.

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Time-Space Analysis of Road Traffic Flows in Seoul (서울시 도로교통흐름에 대한 시.공간적 분석)

  • Lee, Keum-Sook;Min, Hee-Hwa;Park, So-Hyen
    • Journal of the Economic Geographical Society of Korea
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    • v.12 no.4
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    • pp.521-539
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    • 2009
  • This study investigates the time-space characteristics of the road traffic flows in Seoul and the relationship with land use patterns. For the purpose, we analyze the road traffic data collected at 118 observation sites over Seoul City area since 1993. We examine the time-trend of the annual average traffic flows per day during the last fourteen years. Three different trends are revealed: rapid increase during the time period between 1993 and 1997, maintenance same level after sharp decrease between year 1997 and 1998, and gradual decrease after sharp decrease between year 2003 and 2004. The spatial distribution patterns of road traffic flows have also been changed significantly during the period. The traffic flows in the urban center have been declined gradually, while the traffic flows in the boundary area and southern CBDs have increased dramatically. In order to examine the relationship with the changes in the land-use patterns and road traffic flows, we analyze the changes in the spatial distribution patterns of population and industries. We developed three multiple linear regression models to test the relationships between the changes in the land-use variables and road traffic flows.

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A New Low Power LFSR Architecture using a Transition Monitoring Window (천이 감시 윈도우를 이용한 새로운 저전력 LFSR 구조)

  • Kim Youbean;Yang Myung-Hoon;Lee Yong;Park Hyuntae;Kang Sungho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.8 s.338
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    • pp.7-14
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    • 2005
  • This paper presents a new low power BIST TPG scheme. It uses a transition monitoring window (TMW) that is comprised of a transition monitoring window block and a MUX. When random test patterns are generated by an LFSR, transitions of those patterns satisfy pseudo-random gaussian distribution. The Proposed technique represses transitions of patterns using a k-value which is a standard that is obtained from the distribution of U to observe over transitive patterns causing high power dissipation in a scan chain. Experimental results show that the Proposed BIST TPG schemes can reduce scan transition by about $60\%$ without performance loss in ISCAS'89 benchmark circuits that have large number scan inputs.