• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.57-66
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• 2004

When we estimate an origin-destination matrix from traffic counts. origin-destination matrix estimation from traffic counts according to the selected optimal traffic counting links is method for improving the results of origin-destinaation matrix estimation and for increasing economic efficiency. This paper proposed model of selecting traffic counting links using integer program technique, and selected a traffic counting links using this model, and estimated and origin-destingtion matrix from traffic counts according to the selected optimal traffic counting links. Also, we compared a result of estimating origin-destination matrix from the selected optimal traffic counting links using this model to a result of estimating origin-destination matrix from the randomly selected traffic counting links. The error analysis result was more improved a result of origin-destination matrix estimation using this model than a result of randomly selected links.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.1
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• pp.219-232
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• 2023

Mobility services need to change according to the regional characteristics of the target service area. Accordingly, analysis of mobility patterns and characteristics based on Origin-Destination (OD) data that reflect travel behaviors in the target service area is required. However, since conventional methods construct the OD data obtained from the administrative district-based zone system, it is hard to ensure spatial homogeneity. Hence, there are limitations in analyzing the inherent travel patterns of each mobility service, particularly for new mobility service like Demand Responsive Transit (DRT). Unlike the conventional approach, this study applies a data-driven clustering technique to conduct spatial analyses on OD travel patterns of regional mobility services based on reconstructed OD data derived from re-aggregation for original OD distributions. Based on the reconstructed OD data that contains information on the inherent feature vectors of the original OD data, the proposed method enables analysis of the spatial characteristics of regional mobility services, including public transit bus, taxi and DRT.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.61-71
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• 2005

We evaluated the availability of Origin-Destination Matrix from traffic counts Using conjugate gradient method to large scale networks by applying it to the networks in 246 zones. As a result of the analysis of the consistency of the model on Nationwide Networks, the upper and lower levels in model had the systematic relationship internally. From the analysis of the estimable power or the model according to the number of traffic counting links, the error in traffic volume had the estimable power in the range of permissible error. In addition, the estimable power of estimation of an Origin-Destination Matrix was more satisfactory than that of existing methods. We conclude that conjugate gradient method cab be applied to nationwide networks if we can make sure that the algorithm of the developed model is reliable by doing various kinds of experiment.

• Health Policy and Management
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• v.27 no.3
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• pp.229-240
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• 2017

Background: This study purposed to analyze the spatial accessibility of women in childbearing age to the healthcare organizations (HCOs) providing delivery services in Gangwon-do. Methods: Network analysis was applied to assess the spatial accessibility based on the travel time and road travel distance. Travel time and travel distance were measured between the location of HCOs and the centroid of the smallest administrative areas, eup, myeon, and dong in Gangwon-do. Korean Transport Database Center provided road network GIS (Geographic Information System) Database in 2015 and it was used to build the network dataset. Two types of network analysis, service area analysis and origin-destination (OD)-cost matrix analysis, applied to the created network dataset. Service area analysis defined all-accessible areas that are within a specified time, and OD-cost matrix analysis measured the least-cost paths from the HCOs to the centroids. The visualization of the number of the HCOs and the number of women in childbearing age on the Ganwon-do map and network analysis were performed with ArcGIS ver. 10.0 (ESRI, Redlands, CA, USA). Results: Twenty HCOs were providing delivery services in Gangwon-do in 2016. Over 50% of the women in childbearing age were aged more than 35 years. Service area analysis found that 89.56% of Gangwon-do area took less than 60 minutes to reach any types of HCOs. For tertiary hospitals, about 74.37% of Gangwon-do area took more than 60 minutes. Except Wonju-si and Hoengseong-gun, other regions took more than 60 minutes to reach the tertiary hospital. Especially, Goseong-gun, Donghae-si, Samcheok-si, Sokcho-si, Yanggu-gun, Cheorwon-gun, and Taebaek-si took more than 100 minutes to the tertiary hospital. Conclusion: This study provided that the accessibility toward the tertiary hospital was limited and it may cause problems in high-risk delivery patients such as over 35 years. Health policy makers will need to handle the obstetric accessibility issues in Gangwon-do.

• The Korean Journal of Health Service Management
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• v.13 no.1
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• pp.15-30
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• 2019

Objectives: This study aimed to analyze people's accessibility to medical institutions providing national gastric cancer screening services in Gangwon-do using a geographic information system(GIS). Methods: To assess the spatial accessibility, network analysis was applied. Two types of network analysis-Service area analysis and origin-destination cost matrix(OD-cost matrix)-were applied to create network dataset. Results: The results of the analysis of the service area revealed that it took more than 60 minutes each to reach tertiary hospitals and general hospitals from 74.4% and 9.6% of Gangwon-do areas, respectively. Similarly, it took more than 60 minutes each to reach hospitals and clinics from 4.2% and 3.4% of Gangwon-do areas, respectively. The results of the OD-cost revealed that there were large regional variations in distance and time taken to reach the medical institutions. Conclusions: there were regional variations of spatial accessibility between Si and Gun in Gangwon-do.

• Journal of Korean Society of Rural Planning
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• v.23 no.2
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• pp.43-54
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• 2017

When an age of low growth and population decline, population migration plays an important role in spatial structure of region. There have been many researches on migration and regional spatial structure. The purpose of this study is to examine the changes of Gwangju and Jeonnam region's spatial structure and central area using social network analysis methods. For analysis it was used that population and migration data and passenger OD(Origin and Destination) travel data released by Statistics Korea and Korea Transport Database(KTDB). Using Gephi 0.8.2, migration and passenger OD networks were visualized, and this describe network flow and density. The results of the network centrality analysis show that the most populated village is not always network center though population mass is an important factor of central places. The average eigenvector centrality of 2010 migration is the lowest during 2005-2015, and it means few regions have high centralities. When comparing migration and travel networks, travel data is more effective than migration data in determining the central location considering spatial functions.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.2
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• pp.80-93
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• 2018

Public transit services are generally analyzed based on the correlation of demand and supply. The computation of supply uses accessibility while demand uses travel demands estimation based on residential population. However, the traditional demand estimation has a limitation in analysing in micro-scale compared to the smartcard data traffic. This study analyzed potential improvement of public transit services using smartcard traffic data. The supply of transportation was defined using time distance accessibility. Also, time loss was calculated in those origin destination(OD) pairs where time distance accessibilities are relatively low. The proposed method was applied at Seoul. The results showed that the areas where OD pairs need improvement include Seodaemun-gu, Guro-gu and Nowon-gu.

• Journal of Korean Society of Transportation
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• v.33 no.2
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• pp.113-124
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• 2015

The KOTI(Korea Transport Institute) released the new version of KTDB(Korea Transport DataBase) in public. The new KTDB is different from the past KTDB in using the concept of trip generation and trip attraction instead of using the concept of Origin-Destination (OD), which was used in the past KTDB. Thus, the appropriate analysis method for future travel demand became necessary for the new type of KTDB. The method should be based on the concept of PA(Production-Attraction). This study focused on analysis of trip generation and trip distribution related to newly generated trips by future land developments. The study also described clearly the standardized forecasting process and methods with PA travel tables. The study showed that the analysis results with OD-based analysis can be different from the results with PA-based analysis in forecasting travel demand for a simple example case even though they used exactly same orignal travel data. Therefore, this study emphasized that a proper method should be applied with the new PA-based KTDB. It is necessary to prepare and disseminate guidelines of the proper forecasting method and application with PA-based travel data for practician.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.127-135
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• 2018

In countries and regions population plays an important role. Recently the importance of population migration increased as population growth slowed. Researches on population migration are mainly focused on the analysis of the population movement factors and the regional structure analysis using the network analysis method. Analysis of regional structure through population movement is not enough to explain the phenomenon of migration of small cities and rural regions. In this study, to overcome the limit of previous studies the characteristics of the population movement rate according to the size of the population were analyzed. Also network analysis using the population movement OD (Origin and Destination) and population movement rate OD were conducted and the results of them were compared. As the results of analysis by the regional population scale, the population movement by population size showed a big difference in the areas with more than 100 thousand people and less than 100 thousand people. Migration to the outside of the province was the most frequent in regions with 30,000~50,000 people. The population migration rate network analysis result showed that the new area with large population inflow capacity was identified, which could not be found in the population movement network analysis because population movement number is small. The population movement rate irate is expected to be used to identify the central regions of the province and to analyze the difference in resident attractiveness.

• Journal of Korea Port Economic Association
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• v.23 no.4
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• pp.115-137
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• 2007

Due to the economic growth of China and the geographic advantage that Gunsan and Janghang ports are close to China, recently traffic of China is rapidly increasing and the role of Gunsan & Janghang ports as a gateway port of west coast became more important. There, however, remains that Gunsan and Janghang port still don't equip with enough facilities and strategies to handle increasing traffic. The purpose of this paper is to analyze O/D data of Gunsan.Janghang Port and present the result of O/D as preliminary data. O/D data of Gunsan and Janghang had been analyzed by kinds of general cargoes and from/to China's ports and this paper suggests to the competitive strategies of Gunsan and Janghang port to attract cargoes from/to China particularly.