• Title/Summary/Keyword: Geographical distance

Search Result 310, Processing Time 0.03 seconds

Impact of Information and Communication Technologies on Spatial Structure (정보화와 정보기술이 공간구조에 미친 영향)

  • 박삼옥;최지선
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.6 no.1
    • /
    • pp.119-144
    • /
    • 2003
  • This study attempts to figure out the impact of Information and communication technologies (ICTs) on spatial structure and to speculate on spatial strategies in the electronic economy from a geographical perspective. The unprecedented development of ICTs based on the explosive use of the Internet was enough to lead to the expectation that physical distance would not be a significant barrier in business activities. In fact, however, at least at a current stage, the development of ICTs has not automatically removed the inequality in spatial structure. The accessibility to electronic space is different by economic and social status within a country as well as between countries. The importance of place, locality, and place-specific assets has been strengthened in the global economy. Physical proximity is still of great importance because it helps to minimize transaction costs, to exploit place-specific social networks, and to accumulate credibility for successful businesses. Likewise, the development of electronic commerce such as B2B and B2C EC also does not necessarily result in the ignorance of place and locality. Rather, the recognition of the importance of spatial strategies is extremely important for the success in online businesses. As a conclusion, the spatial dimension becomes more important in the digital era for successful businesses and balanced regional developments than ever before. The need for the improvement of ICT infrastructures, the development of human resources, and the establishment of regional innovation systems in peripheral areas cannot be overemphasized even in the digital era.

  • PDF

The Characteristics of Intra-Urban Migration in Seoul (서울시 내부 인구이동의 특성에 관한 연구)

  • Choi, Eun-Young;Cho, Dae-Heon
    • Journal of the Korean association of regional geographers
    • /
    • v.11 no.2
    • /
    • pp.169-186
    • /
    • 2005
  • This paper has focused on the geographical patterns of migrations and the influence of housing value(apartment) per pyung on the migrations within the one city(Seoul) for 1995$\sim$2003. The migration flows which are composed of the origin, the destination and the number of migrants, are examined at the administrative gu and dong level. As most migrations occur among adjacent gus and dongs, short-distance migration is prominent But there is a tendency for the short-distance migrations to occur between specific regions. Since the economic crisis of 1997 out of which Korea was rescued by IMF, differentiation of housing price is so evident that residental relocation is selective among dongs. It seems that the differentiation of housing price has begun to facilitate the relocation of households. Certain social groups are excluded from high-quality residences, as they cannot afford the high price. The number of migrants between dongs is closely related to the variation of the housing value per pyung within dongs. The short-distance migration may reflect this phenomena simultaneously. It seems that the intra-urban migrations in Seoul play a important role to produce and reinforce the residential segregation.

  • PDF

Island Biogeographic Study on Distribution Pattern of the Naturalized Plant Species on the Uninhabited Islands in Korea (우리나라 무인도서의 귀화식물 분포에 대한 섬생물지리적 연구)

  • Chung, Jae-Min;Hong, Kyung-Nak
    • Journal of Ecology and Environment
    • /
    • v.29 no.6
    • /
    • pp.489-494
    • /
    • 2006
  • For the ecosystem conservation and the effective management of naturalized plant species on 261 uninhabited islands distributed in southern and western sea in Korea, we tested the interrelationship between the pattern of distribution and dispersal of the naturalized plant species and the factors of geographical environment of uninhabited islands such as island area, distance from mainland, latitude, longitude, human impacts and habitat diversity. Out of 261 uninhabited islands surveyed, 106 species of the naturalized plants occurred on 229 (87.7%) islands. The naturalized plant species per island averaged 4.6 (SD=4.07) species, and plant species number were higher in southern group (87 species) than in western group (64 species) of islands. Plant species occurred on more than 100 islands were three species : Rumex crispus L. (153 islands), Erigeron annuus Pers. (130 islands), and Conyza canadensis (L.) Cronquist (121 islands), the highest grade '5' of 'degree of naturalization'. The occurrence frequency of 106 naturalized plant species was significantly correlated with island area, distance to mainland, strength of human impacts, and latitude and longitude. Correlation coefficient (r=-0.330) between occurrence frequency and distance from mainland was higher than between occurrence frequency and island area (r=-0.182). The result of path analysis confirmed that plant species number was significantly affected by island area p=0.336) and distance from mainland (p=-0.490), but in this analysis the effect of human impacts on plant species number was very weak (p=0.003). On the basis of these results, strategies on the conservation of ecosystem and the management of naturalized plant species in the uninhabited islands of Korea were discussed.

A Spatial Interpolation Model for Daily Minimum Temperature over Mountainous Regions (산악지대의 일 최저기온 공간내삽모형)

  • Yun Jin-Il;Choi Jae-Yeon;Yoon Young-Kwan;Chung Uran
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.2 no.4
    • /
    • pp.175-182
    • /
    • 2000
  • Spatial interpolation of daily temperature forecasts and observations issued by public weather services is frequently required to make them applicable to agricultural activities and modeling tasks. In contrast to the long term averages like monthly normals, terrain effects are not considered in most spatial interpolations for short term temperatures. This may cause erroneous results in mountainous regions where the observation network hardly covers full features of the complicated terrain. We developed a spatial interpolation model for daily minimum temperature which combines inverse distance squared weighting and elevation difference correction. This model uses a time dependent function for 'mountain slope lapse rate', which can be derived from regression analyses of the station observations with respect to the geographical and topographical features of the surroundings including the station elevation. We applied this model to interpolation of daily minimum temperature over the mountainous Korean Peninsula using 63 standard weather station data. For the first step, a primitive temperature surface was interpolated by inverse distance squared weighting of the 63 point data. Next, a virtual elevation surface was reconstructed by spatially interpolating the 63 station elevation data and subtracted from the elevation surface of a digital elevation model with 1 km grid spacing to obtain the elevation difference at each grid cell. Final estimates of daily minimum temperature at all the grid cells were obtained by applying the calculated daily lapse rate to the elevation difference and adjusting the inverse distance weighted estimates. Independent, measured data sets from 267 automated weather station locations were used to calculate the estimation errors on 12 dates, randomly selected one for each month in 1999. Analysis of 3 terms of estimation errors (mean error, mean absolute error, and root mean squared error) indicates a substantial improvement over the inverse distance squared weighting.

  • PDF

Evaluation of Suitable REDD+ Sites Based on Multiple-Criteria Decision Analysis (MCDA): A Case Study of Myanmar

  • Park, Jeongmook;Sim, Woodam;Lee, Jungsoo
    • Journal of Forest and Environmental Science
    • /
    • v.34 no.6
    • /
    • pp.461-471
    • /
    • 2018
  • In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.

Genetic Diversity of Indigenous Cattle Populations in Bhutan: Implications for Conservation

  • Dorji, T.;Hanotte, O.;Arbenz, M.;Rege, J.E.O.;Roder, W.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.16 no.7
    • /
    • pp.946-951
    • /
    • 2003
  • The Genetic diversity and relationship of native Siri (Bos indicus) cattle populations of Bhutan were evaluated using 20 microsatellite markers. A total of 120 Siri cattle were sampled and were grouped into four populations according to their geographical locations which were named Siri West, Siri South, Siri Central and Siri East cattle. For each, 30 individuals were sampled. In addition, 30 samples each of Indian Jaba (B. indicus), Tibetan Goleng (B. taurus), Nepal Hill cattle (B. indicus), Holstein Friesian (B.taurus) and Mithun (B. frontalis) were typed. The mean number of alleles per loci (MNA) and observed heterozygosity (Ho) were high in the Siri populations ($MNA=7.2{\pm}0.3$ to $8.9{\pm}0.5$ and $Ho=0.67{\pm}0.04$ to $0.73{\pm}0.03$). The smallest coefficient of genetic differentiation and genetic distance ($F_{ST}=0.015$ and $D_A=0.073$) were obtained between Siri West and Siri Central populations. Siri East population is genetically distinct from the other Siri populations being close to the Indian Jaba ($F_{ST}=0.024$ and $D_A=0.084$). A high bootstrap value of 96% supported the close relationship of Siri South, Siri Central and Siri West, while the relationship between Siri East and Jaba was also supported by a high bootstrap value (82%). Data from principal component analysis and individual assignment test were in concordance with the inference from genetic distance and differentiation. In conclusion we identified two separate Siri cattle populations in Bhutan at the genetic level. One population included Siri cattle sampled from the West, Central and South of the country and the other Siri cattle was sampled from the East of the country. We suggest that Siri cattle conservation program in Bhutan should focus on the former population as it has received less genetic influence from other cattle breeds.

A Zone based Routing algorithm for VANET (VANET 환경에서 구역 기반의 라우팅 알고리즘)

  • Lee, Seung-Hwan;Seok, Seung-Joon
    • Journal of Digital Convergence
    • /
    • v.10 no.9
    • /
    • pp.325-332
    • /
    • 2012
  • VANET(Vehicular Ad-hoc Network), which is a technology to create a network among vehicles, decides the route to the destination using information of neighbors within the transmission range as transmission nodes. The existing routing protocol which uses geographical information can cause delay and disconnection of the network when the density of nodes is not high enough to communicate because it only considers the distance of the relay nodes or destination nodes from the source nodes. To solve the problem, this dissertation suggests a routing algorithm based on zones for stable communications among vehicles in the environment of VANET. I minimize the packet loss rate by dividing the city environment into zones and taking into account not only the distance of the destination but also the density of vehicles to choose the best communications environment. This results in a better performance than the established research when the performance evaluation is implemented.

A Study of Landscape Management Techniques based on Viewing Characteristics of Mountain Landscape - Focused on the Surrounding Areas of Bukhansan Mountain -

  • Park, Moon-Ho
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.38 no.5_2
    • /
    • pp.163-175
    • /
    • 2010
  • This study is based on the viewing characteristics of mountain landscapes. It investigates whether the current landscape management-related regulations are efficient in terms of the viewing characteristics of the mountain landscape against Bukhansan Mountain in which the conventional landscape management techniques were used. In addition, some viewing characteristics of mountain landscapes, such as distance from the view point to the target mountain, angle of elevation, altitude, gradient, have been analyzed and 3 cases of viewing condition have been simulated. The following results were obtained: i) Mountain landscapes can be managed up to 7~8 times of the mountain height with a $5{\sim}9^{\circ}$ of elevation angle. ii) In the Natural Landscape District which is situated on the hillside, it is reasonable to include altitude, gradient as criteria for regulation. iii) According to a simulation of the construction permit height by viewing distance, it was confirmed that buildings can be constructed up to 111.55m when viewing the 20% ridge, 150.75m when viewing the 50% ridge and 189.05m when viewing the 70% ridge. iv) The construction permit height varies depending on the landscape analysis method that is used and the application conditions. It is therefore unfair to apply height limit regulations to all buildings without considering the geographical features or viewing characteristics. v) It is unreasonable to apply 2~3 management techniques to the same area for landscape management. Therefore, we recommend the Focused Landscape Management Area based on the landscape master plan as a integrating mountain landscape management techniques.

Geographic Variations in Four Freshwater Crab (Eriocheir sinensis) Populations throughout Its Distribution Range (분포지역에 따른 민물가재 4집단(Eriocheir sinensis)의 지리적 변이)

  • Yoon, Jong-Man
    • Development and Reproduction
    • /
    • v.13 no.2
    • /
    • pp.97-103
    • /
    • 2009
  • Genomic DNA samples isolated from four geographical freshwater crab (Eriocheir sinensis) populations collected in the inland of the Korean Peninsula (Gunsan, Paju, and Nampo) and a Chinese site, were used for PCR amplification. Seven decamer primers generated 19 specific loci (19/243 loci, 7.81%) in the Gunsan population, 32 (32/215 loci, 14.88%) in the Paju population, 19 (19/231 loci, 8.23%) in the Nampo population and 62 (62/340 loci, 18.24%) in a Chinese population. The average 8.9 specific loci exhibited inter-individual-specific characteristics, thus revealing DNA polymorphisms in the Chinese population. The number of unique shared loci to each population and number of shared loci by the four populations were generated by molecular analysis using seven primers in four populations. 35 unique shared loci to each population, with an average of 5.0 per primer, were observed in the Gunsan population, and 50 loci, with an average of 7.1 per primer, were observed in the Chinese population. The hierarchical dendrogram indicates three main branches: cluster 1 (GUNSAN 01$\sim$GUNSAN 05, PAJU 06$\sim$PAJU 10 and NAMPO 11$\sim$NAMPO 15) and cluster 2 (CHINESE 16, 17, 18, 19 and 20). Conclusively individual no. 20 of the PAJU 10 freshwater crab was most distantly related to CHINESE no. 20 (genetic distance = 0.667). Taken together, these results demonstrate the potential of RAPD analysis to identify diagnostic markers for the identification of four freshwater crab populations.

  • PDF

Spatial Autocorrelation Analysis of Carex humilis on Mt. Giri by RAPD (RAPD에 의한 지리산 내 산거울 집단의 공간적 상관관계 분석)

  • Lee, Bok-Kyu;Lee, Byeong-Ryong;Huh, Man-Kyu
    • Journal of Life Science
    • /
    • v.20 no.9
    • /
    • pp.1287-1293
    • /
    • 2010
  • The spatial distribution of alleles and geographical distances of a Carex humilis population on Mt. Giri in Korea were studied. A total of 102 DNA fragments (bands) were found among 107 plants. Among these 102 bands, 48 (47.1%) bands were polymorphic. In a simple variability of subpopulations by the percentage of polymorphic bands, distances I and V exhibited the lowest variation (16.7%). Distance VIII showed the highest variation (22.6%). The total genetic diversity (H) was 0.076 across species. Class VIII had the highest H (0.093), while class I had the lowest (0.063). Genetic similarity of individuals was found among subpopulations at up to a scale of 60 m distance, and this was partly due to a combination of alleles. Within the Mt. Giri population, a strong spatial structure was observed for RAPD markers, indicating a very low amount of migration among subpopulations and that the distribution of individual genotypes of a given population was clumped. The present study demonstrated that analysis of RAPD markers could be successfully used to study the spatial and genetic structures of C. humilis.