• Asia Marketing Journal
• /
• v.9 no.2
• /
• pp.97-129
• /
• 2007

The critical link between consumer-based internet ordering and the delivery of the product to the consumer is a key success factor in online shopping. Market areas of online shopping company implies the range of space where products ordered from online shopping can be physically delivered to customers distributed over space with reasonable shipping cost and lead time through the physical distribution network. The average rate of growth in online shopping is 36% per year in Korea for the last 5 years. But there are no maps available that describe sales/delivery density of online shopping, few researches are focused on the short-term/long-term adaptation to demand increase by online shopping. In this paper (1) Maps of trade area are described indicating the sales/delivery density around the nation. (2) Empirical researches suggested that short-term adaptation to demand increase resulted in price reduction and service in enhancement of service quality in local transportation. But the long-term adaptation on the parts of parcel delivery industry are to be investigated in future researches.

• Journal of the Korean Geographical Society
• /
• v.50 no.5
• /
• pp.485-503
• /
• 2015

This study aims at evaluating geomorphological classification systems to predict the occurrence of landslides in mountainous region in Korea. Geomorphological classification systems used in this study are Catena, TPI, and Geomorphons. Study sites are Gapyeong-gun, Hoengseong-gun, Gimcheon-si, Yeoju-si/Yicheon-si in which landslide occurrence data were collected by local governments from 2001-2014. Catena method has objective classification standard to compare among regions objectively and understand the result intuitively. However, its procedure is complicated and hard to be automated for the general public to use it. Both TPI and Geomorphons have simple procedure and GIS-extension, therefore it has high accessibility. However, the results of both systems are highly dependent on the scale, and have low relevance to geomorphological formation process because focusing on shape of terrain. Three systems have low compatibility, therefore unified concept are required for broad use of landform classification. To assess the effectiveness of prediction on landslide by each geomorphological classification system, 50% of geomorphological classes with higher landslide occurrence are selected and the total landslide occurrence in selected classes are calculated and defined as 'predictive ability'. The ratio of terrain categorized by 'predictive ability' to whole region is defined as 'vulnerable area ratio'. An indicator to compare three systems which is predictive ability divided by vulnerable area ratio was developed to make a comprehensive judgment. As a result, Catena ranked the highest in suitability.

• Journal of Ecology and Environment
• /
• v.29 no.3
• /
• pp.219-225
• /
• 2006

To study song themes and variation of Yellow-throated Bunting, we obtained and analyzed recordings from 45 males breeding in 16 deciduous forests of 6 provinces. We classified the 3,245 songs into a total of 164 song themes and 1,024 song variants according to the identification on the base of difference(lexicon) in 640 syllable compositions. Males had one to six song themes and averaged 3.5 themes. No males shared an identical song theme. Males had $5{\sim}14$ syllables (ave. 9.4) in one song theme and males increased effectively their repertoire size by changing syllable composition (i.e. adding, deleting, or substituting one or more syllables) in a single song theme. The number of variants averaged 5.1 (range 1 to 31) per song theme. Individual variability was highest in the terminal elements of the song. In PCA, the 16 populations are clearly separated on Co. I based on shared syllable and on Co. II based on unique syllable. Similarity of songs based on shared syllables by distance coefficients, showed a pattern of concordance with geography. Pairwise similarity declined with increasing distance among recording sites. 16 different geographical regions by the syllable were divided in UPGMA tree.

• Journal of Life Science
• /
• v.25 no.3
• /
• pp.323-328
• /
• 2015

The study of microbial diversity and richness in soil samples from a volcanic island named Ulleungdo, located east of South Korea. The soil bacterial communities on the Ulleungdo were analyzed using pyrosequencing method based on 16S rRNA gene. There were 1,613 operational taxonomic units (OUT) form soil sample. From results of a BLASTN search against the EzTaxon-e database, the validated reads (obtained after sequence preprocessing) were almost all classified at the phylum level. Proteobacteria was the most dominant phylum with 48.28%, followed by acidobacteria (26.30%), actionbacteria (6.89%), Chloroflexi (4.58), Planctomycetes (4.56%), Nitrospirae (1.83%), Bacteroidetes (1.51%), Verrucomicrobia (1.48%), and Gemmatimonadetes (1.11%). α-proteobacteria was the most dominant class with 36.07% followed by Acidobacteria_c (10.65%), Solibacteres (10.64%), δ-proteobacteria (4.42%), γ-proteobacteria (4.29%), Planctomycetacia (4.16%), Actinobacteria_c (4.00%), Betaproteobacteria (3.50%), EU686603_c (2.97%), Ktedonobacteria (2.91%), Acidimicrobiia (1.32%), Verrucomicrobiae (1.27%), Gemmatimonadetes_c (1.11%), Sphingobacteria (1.09%), and GU444092_c (1.06%). Bradyrhizobiaceae was the most dominant family with 22.83% followed by Acidobacteriaceae (10.62%), EU445199_f (5.72%), Planctomycetaceae (4.03%), Solibacteraceae (3.63%), FM209092_f (3.58%), Steroidobacter_f (2.81%), EU686603_f (2.73%), Hyphomicrobiaceae (2.33%), Ktedonobacteraceae (1.75%), AF498716_f (1.46%), Rhizomicrobium_f (1.03%), and Mycobacteriaceae (1.01%). Differences in the diversity of bacterial communities have more to do with geography than the impact on environmental factors and also the type of vegetation seems to affect the diversity of bacterial communities.

• Journal of the Korean Geographical Society
• /
• v.45 no.4
• /
• pp.478-501
• /
• 2010

The purpose of this study is to understand spatial economic inequalities under the framework of the dynamics of economic spaces in relation to the four global megatrends: globalization, knowledge-based economy, information society, and the service world. The international inequalities in East Asia, as well as inter-regional inequalities within Japan, Korea, and Thailand were analyzed. The variables related to the four megatrends, as a whole, have clearly explained the variations in international inequalities in East Asia, as well as the inter-regional inequalities within a nation. The individual impacts of the variables on spatial inequalities are, however, significantly different depending on the spatial scale of analysis and national characteristics. Overall, there has been a convergence trend of international per capita GNI (Gross National Income) in East Asian nations, while both divergent and convergent trends are evident at the regional scale within a nation. Two global oil crises in the 1970s and the East Asian financial crisis in the late 1990s resulted in the discontinuity of the general convergence trend, and have led to the increase of international and inter-regional inequalities in economic activities. This suggests that although the effect of the global crisis differs in each country, in general, the economies of peripheral countries and regions are more vulnerable during a global economic crisis.

• The Korean Journal of Quaternary Research
• /
• v.34 no.1
• /
• pp.41-51
• /
• 2024

The Sincheon wetland shows a remarkable diversity of fluvial landforms, such as river islands, anastomosing channels, braided channels, and sand-gravel bars, which contribute to its rich ecological habitat. The wetland area is characterized by a ecological diversity of herbaceous and woody plants. Significant changes in land cover within the wetlands were observed from 2008 to 2020. Notably, there was a rapid decrease in agricultural area from 18% to 0.04%, while the vegetation area expanded from 45% to 54%. Concurrently, the water area also experienced a notable increase from 34% to 41%. The surface sediment composition in the studied area displays sandy loam characteristics and exhibits acidic soil properties. Sediment acidity tends to increase downstream and in the central part of channels. Variations in acidity are also observed at nearby collection sites due to the tributaries and local discharge. The presence of dense vegetation in river islands and bars has led to a significant transformation of sediments into soil, with this change being more pronounced downstream, particularly near the weirs. The installation of a weir in Sincheon wetland is believed to have a significant impact on altering flow velocities between upstream and downstream sections, as well as influencing erosion and sediment deposition patterns. However, given the formation of landforms in response to weirs, effective administration and management are essential to address potential risks of catastrophic environmental disruptions, such as the removal of weirs and/or the maintenance of river channels.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.3
• /
• pp.156-170
• /
• 2006

Determining the best visibility positions on terrain surface has been one of the frequently used analytical issues in GIS visibility analysis and the search for a solution has been carried out effectively using spatial search techniques. However, the spatial search process provides operational and methodological challenges for finding computational algorithms suitable for solving the best visibility site problem. For this problem, current GIS visibility analysis has not been successful due to limited algorithmic structure and operational performance. To meet these challenges, this paper suggests four algorithms explored robust search techniques: an extensive iterative search technique; a conventional solution based on the Tornqvist algorithm; genetic algorithm; and simulated annealing technique. The solution performance of these algorithms is compared on a set of visibility location problems and the experiment results demonstrate the useful feasibility. Finally, this paper presents the potential applicability of the new spatial search techniques for GIS visibility analysis by which the new search algorithms are of particular useful for tackling extensive visibility optimization problems as the next GIS analysis tool.

• Clinical and Experimental Pediatrics
• /
• v.50 no.3
• /
• pp.262-267
• /
• 2007

Purpose : The prevalence of hepatitis A virus (HAV) in a certain community reflects that community's living standards and hygienic conditions. And the pattern of HAV infection differs over time and geography. Recently, a shift in prevalence has been observed in cases from chilhood to adulthood. We studied the HAV antibody prevalence in the general population in Busan. Methods : From October 2004 to March 2005, total 472 subjects were tested for HAV antibodies. All samples were collected from patients in Maryknol Hospital. Results : The overall seropositive rate was 22.8% (108/472). The seropositive rates were 1.7% in subjects aged 2-5 years, 1.7% in 6-10 years, 0% in 11-20 years, 40.5% in 21-30 years, 82.1% in 31-40 years, 94.7% in 41-50 years, and 100% in subjects aged over 50 years. There was no significant gap between gender groups. Conclusion : As the socioeconomic conditions in Korea have improved, the HAV seropositive rate in school-aged children has dramatically decreased in the last 20 years. But, the seropositive rate of HAV didn't differ according to gender. The seropositive rate of HAV in the pediatric group was very low, which suggests the increasing possibility of clinical HAV infection in adults in the near future. Therefore, we should actively prevent the spread of hepatits A virus. In order to do that, we need to reorganize our lifestyle and personel hygiene and carry out active and passive immunization to high risk groups.

• Journal of the Korean association of regional geographers
• /
• v.9 no.1
• /
• pp.53-65
• /
• 2003

The aim of this study is to examine the regional features of shipbuilding-allied industries comprehensively. Inaddition, this study would offer groundwork to construct spatial networks of shipbuilding-allied industries. Relatively in short term, large modem shipbuilding firms of South Korea have developed under the national strategic support, around southeast coast region. Although small shipbuilding firms and marine equipment firms have supported regional economy, these firms have scaled down their functions and roles due to the national policy. In the long tenn, Korean shipbuilding-allied industries have limitations in stable development, because they have separated their roles. Consequently it is necessary the balanced development of large, medium, and small shipbuilding firms and linkage system with marine equipment firms for overall development of shipbuilding-allied industries. This study suggests two spatial strategy for shipbuilding-allied industries development. First, we need to construct a shipbuilding specialization area which agglomerates competent parts firms adjacent to large shipyards. Second, in national strategy, a long term strategy is required to utilize extremely synergy and external effects induced from a shipbuilding duster of southeast coast region which systematically combines shipbuilding-allied industries, universities, the government authorities, and research institutions.

• Journal of the Korean association of regional geographers
• /
• v.17 no.4
• /
• pp.416-431
• /
• 2011

Hiking trails in Mt Jiri, and Mt Halla, National Park have been examined in terms of their degrading factors. The trails are deteriorated by natural erosion processes as well as human trampling. Trail deterioration is classified into tread lowering, sidewall retreat, path widening and divergence based upon a place where erosional processes occur. Tread lowering and sidewall retreat is generally produced by natural erosion factors, whereas path widening and divergence is generated by human trampling. Rainwash is the most contributing process to tread lowering. By contrast, several processes such as rainwash, needle ice action, deflation, tree falling and animal activity play a major role in sidewall retreat according to physical conditions of a hiking trail. Path widening and divergence could be classified by a factor producing human trampling. There are lots of cases related to rainwash such as the tree root, gravel, and bedrock, exposed by a surface flow lowering a tread and the riser produced by tread scouring. A puddle of rainwater on a flat tread and a fallen tree of Abies koreana in a forest region are also major factors to cause path widening and divergence. A paved tread with stones encourages a hiker to walk out of a trail. Taking a shortcut also results in path widening and divergence without a factor giving a hiker inconvenience on a trail.