• 산업경영시스템학회지
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• 제36권3호
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• pp.71-78
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• 2013

An efficient vehicle routing heuristic for different vehicle moving times for forward and backward between two points is studied in this research. Symmetric distance or moving times are assumed to move back and forth between two points in general, but it is not true in reality. Also, various moving speeds along time zones are considered such as the moving time differences between rush hours or not busy daytimes. To solve this type of extremely complicated combinatorial optimization problems, delivery zones are specified and delivery orders are determined for promising results on the first stage. Then delivery orders in each zone are determined to be connected with other zones for a tentative complete delivery route. Improvement steps are followed to get an effective delivery route for unsymmetric-time-varing vehicle moving speed problems. Performance evaluations are done to show the effectiveness of the suggested heuristic using computer programs specially designed and developed using C++.

• The Korean Journal of Ecology
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• 제21권5_2호
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• pp.501-518
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• 1998

Mt. Paektu(2,749.6m)m the biggest mountain in Northeast Asia, located on the border line of Korea and China is characterized as an aspite with broad gentle mountain area and rich biota. however, it seems that the study of forest vegetational feature or vegetation zones in the whole area of this mountain is not yet sufficient in spite of contribution by many investigators. in this paper thermal climatic approach was carried out for the determination of vegetation zones of the mountain with the meteorological data of four stations including Cheonjj and various vegetational data. the application of Warmth Index and/or coldness Index(Kira 1977) for the determination of forest vegetation boundary was useful also here, and their boundaries largely coincided with those of thermal indicies obtained in the Korean Peninsula(Yim and Kira, 1975), including the lapse rate of air temperature along increasing elevation. However, in the mountain the boundary of vegetation zones in not clear like those of mountains in Korea. It may be due so the topographic differences between this area and the Korean Peninsula. Besides, the broad ecotones between different vegetations in this area support the vegetation continum concept rather than the unit concept, and the limit of timber line or tree line reflects various hypothesis(Steven and fox 1991). Therefore, for the explantion of vegetation zone of this area should be considered topography or soil condition, for example, as known the hierachy of ecological units (zonobiomes, orobiomes and pedobiomes, Walter, 1973).

• Environmental Engineering Research
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• 제19권3호
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• pp.197-203
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• 2014

This study estimated spatial and seasonal variation of water quality to understand characteristics of Nakdong river basin, Korea. All together 11 parameters (discharge, water temperature, dissolved oxygen, 5-day biochemical oxygen demand, chemical oxygen demand, pH, suspended solids, electrical conductivity, total nitrogen, total phosphorus, and total organic carbon) at 22 different sites for the period of 2003-2011 were analyzed using multivariate statistical techniques (cluster analysis, principal component analysis and factor analysis). Hierarchical cluster analysis grouped whole river basin into three zones, i.e., relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) based on similarity of water quality characteristics. The results of factor analysis/principal component analysis explained up to 83.0%, 81.7% and 82.7% of total variance in water quality data of LP, MP, and HP zones, respectively. The rotated components of PCA obtained from factor analysis indicate that the parameters responsible for water quality variations were mainly related to discharge and total pollution loads (non-point pollution source) in LP, MP and HP areas; organic and nutrient pollution in LP and HP zones; and temperature, DO and TN in LP zone. This study demonstrates the usefulness of multivariate statistical techniques for analysis and interpretation of multi-parameter, multi-location and multi-year data sets.

• Parasites, Hosts and Diseases
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• 제45권2호
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• pp.129-132
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• 2007

The geographical distribution and ecological preferences of Haemaphysalis in domestic animals in Iran were studied 4 times a year from April 2003 to March 2005. A total of 1,622 ixodid tick specimens were collected from 3 different zones. Among them, 108 (6.7%) Haemaphysalis ticks, consisting of 6 species, were identified; H. punctata (3.4%), H. parva (0.5%), H. sulcata (0.6%), H. choldokovskyi (1.7%), H. concinna (0.06%) and Haemaphysalis sp. (0.6%). H. punctata was the most abundant species, whereas H. concinna was the rarest species collected in humid and sub-humid zones on cattle, sheep and goats. H. choldokovskyi was principally collected from sheep and goats grazed in cold mountainous areas. The infested areas consisted of Caspian Sea (Guilan, Mazandaran, Golestan, and central provinces), mountainous (Azarbaiejan, Ardebil, Kohgilouyeh, and Kordestan) and semi-dessert (Khorasan, Semnan, Herman, Sistan, and Baluchestan) zones. The Caspian Sea zone (23.6%) was the most highly infested region. The results show that various species of Haemaphysalis ticks infest domestic ruminants in Iran and each tick species show characteristic geographical distributions.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.224-224
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• 2015

The East Asia monsoon is one of the most complex atmospheric phenomena caused by Land-Sea thermal contrast. It plays essential role in fulfilling the water needs of the region but also poses stern consequences in terms of flooding and droughts. This study analyzed the influence of Global Sea Surface Temperature Anomalies (SSTA) on occurrence of droughts in the East Asia monsoon region ($20^{\circ}N-50^{\circ}N$, $103^{\circ}E-149^{\circ}E$). Standardized Precipitation Index (SPI) was employed to characterize the droughts over the region using 30-year (1978-2007) gridded rainfall dataset at $0.5^{\circ}$ grid resolution. Due to high variability in intensity and spatial extent of monsoon rainfall the East Asia monsoon region was divided into the homogeneous rainfall zones using cluster analysis method. Seven zones were delineated that showed unique rainfall regimes over the region. The influence of SSTA was assessed by using lagged-correlation between global gridded SSTA ($0.2^{\circ}$ grid resolution) and SPI of each zone. Sea regions with potential influence on droughts in different zones were identified based on significant positive and negative correlation between SSTA and SPI with a lag period of 3-month. The results showed that SSTA have the potential to be used as predictor variables for prediction of droughts with a reasonable lead time. The findings of this study will assist to improve the drought prediction over the region.

• 대한토목학회논문집
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• 제30권5D호
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• pp.461-465
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• 2010

본 연구의 목적은 예비타당성조사에서 수행한 도시부 간선도로 확장공사로 인한 부(-)의 편익을 산정하고 이것이 경제성 평가에 미치는 영향을 분석하는 것이다. 북부간선도로 태릉-구리 간 확장사업의 실제 예비타당성조사 단계에서 통상적인 편익 산출 방법론을 적용하였으며, 공사로 인한 차량운행비용, 통행시간, 교통사고, 환경비용의 부(-)의 편익을 산출하였다. 분석 결과, 부(-)의 편익의 적용여부는 사업의 경제적 타당성 평가에 많은 영향을 주는 것으로 나타났다. 하지만 공사기간, 공사의 종류, 공사구간 및 교통량 등에 따라 부(-)의 편익에 많은 영향을 주는 감소되는 용량 및 자유속도가 현저하게 다를 수 있으며, 향후에는 이러한 요소와 용량 및 자유속도에 대한 상세한 연구가 필요할 것이다.

• 한국실내디자인학회논문집
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• 제20권5호
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• pp.96-104
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• 2011

Assuming that different spatial types involves the change of observation time to acquire the spatial information, this study intended to analyze the observation time by interior space types and derive the proper time for spatial evaluation. Coming to the study method, in order to analyze the characteristics of observation time in the image evaluation of interior space by types, it looked into the observation time chosen by the testees during evaluation. The findings of this study are as follows: First, the observation time differed by genders and spatial types: men's average time was longest for modern (93.3 sec.) and natural (89.4 sec.) spaces; women's average time was longest for classic space (110.7 sec.), which was the shortest for men. Second, the intensity of observation time zone differed by spatial types: this finding can imply that different design types require different establishment of observation time for evaluation even if the spatial elements are the same. Third, analyzing the distribution of time zones chosen by most testees showed that men's observation time zones were more intensely distributed than those of women. Fourthly, the observation lime for general space could be derived from the gender-based comparison that excluded the difference by types, but considering that different design types lead to different observation time, it could be seen as proper for evaluation of interior space to establish the difference of observation time by spatial types. Finally, Analysis showed the highest preference to the time '(3)'. However, obtaining information presented is the most highly effective time is '(6). Thus, the preferred time zone is different and effective, according to the results of the analysis.

• 대한교통학회지
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• 제6권2호
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• pp.35-48
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• 1988

Amongst various analytic methods of internal structure of city, the factor analysis method which uses O-D matrix data has some merits and characteristics compared to other methods. 1) It is possible to find one certain interaction and flow pattern between traffic zones with in a city through reanalyzing O-D data which is too complex to grasp specific meaning or pattern of flow systems. 2) It can be easily visualized the traffic flow pattern by using adequate graphic techniques, and also can clarify the functional areas whose interaction linkages are significantly strong enough between each other. In this study, the taxi traffic O-D data between 42 traffic zones in Kwang-ju city was reanalyzied by varimax rotated factor analysis methods. As a result, four factors that have significant level factor loading (over 0.5 ) and factor score (over 1.0) were sorted out. so to speak four different functional areas were clarified in Kwang-ju city, of the West, the East, the south, and the North functional areas whose interaction linkages are significantly strong enough between each other. In the study, the taxi traffic O-D data between 42 traffic zones in Kwang-ju city was reanalyzied by varimax rotated factor analysis methods. As a result, four factors that have significant level factor loading (over 0.5) and factor score 9over 1.0) were sorted out. so to speak four different functional areas were clarified in Kwang-ju city, of the West, the East, the South, and the North functional area, then these four functional areas are almost coincided with citizen's general conception of community division and administrative district. Accordingly the factor analysis methods using traffic data seems to proved to be very accurate and useful analytic instruments for analyzing flow pattern and clarifying functional areas of city, and believed to provide basic informations and criteria for practical urban land use planning and transportation planning.

• 환경생물
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• 제18권4호
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• pp.411-424
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• 2000

연안생태계의 호염성 톡토기와 개미군집의 생물다양성정도와 변동에 대해 알아보기 위해, 주변환경과 식생이 다른 세지역에서 정량채집을 실시하였다. 종조성이나 분포에 영향을 주는 요인을 찾기 위해 pH, 염도 및 전기전도도를 측정하였다. 연구결과 톡토기의 종조성 이나 분포에는 pH와 식생보다도 토성과 염도가 더 큰 영향을 주는 것으로 나타났다. 그러나 개미의 경우는 집을 지을 적당한 장소를 제공해 줄 수 있는 식생과 조수에 의한 침수에 더 큰 영향을 받는 것으로 사료된다. 모든 조사지역에서 조상대가 조간대보다 다양도가 높았으며 조간대중에서는 모래함량이 높은 동호의 상조대에서 가장 높게 나타났다

• 한국농공학회논문집
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• 제58권3호
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• pp.57-69
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• 2016

In this study, we analyzed the extreme rainfall distribution scenarios based on probable rainfall calculation and applying various time distribution models over the landslide high risk zones in urban areas. We used observed rainfall data form total 71 ASOS (Automated Synoptic Observing System) station and AWS (Automatic Weather Station) in KMA (Korea Meteorological Administration), and we analyzed the linear trends for 1-hr and 24-hr annual maximum rainfall series using simple linear regression method, which are identified their increasing trends with slopes of 0.035 and 0.660 during 1961-2014, respectively. The Gumbel distribution was applied to obtain the return period and probability precipitation for each duration. The IDF (Intensity-Duration-Frequency) curves for landslide high risk zones were derived by applying integrated probability precipitation intensity equation. Results from IDF analysis indicate that the probability precipitation varies from 31.4~38.3 % for 1 hr duration, and 33.0~47.9 % for 24 hr duration. It also showed different results for each area. The $Huff-4^{th}$ Quartile method as well as Mononobe distribution were selected as the rainfall distribution scenarios of landslide high risk zones. The results of this study can be used to provide boundary conditions for slope collapse analysis, to analyze sediment disaster risk, and to use as input data for risk prediction of debris flow.