• Journal of Korean Society of Transportation
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• v.32 no.4
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• pp.410-420
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• 2014

This research suggests a new tram signal priority model which determines signal timings and tram intersection waiting time using analytical method. This model can calculate the signal timings for Early Green and Green Extension among the active tram signal priority techniques by tram detection time of upstream detector. Moreover, it can determine the tram intersection waiting time that means tram intersection travel time delay from a vantage point of tram travel. Under the active tram signal priority condition, priority phases can bring additional green time from variable green time of non-priority phases. In this study, the signal timing and tram intersection waiting time calculation model was set up using analytical methods. In case studies using an isolated intersection, this study checks tram intersection waiting time ranged 12.7 to 29.4 seconds when variable green times of non-priority phases are 44 to 10 seconds under 120 seconds of cycle length.

• Journal of Technology Innovation
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• v.28 no.4
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• pp.63-93
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• 2020

We suggest a new way of specifying the co-evolution of product and process technologies, and integrating it into one of the well-received technology intelligence tools - a technology radar. Cross impact analysis enables us to identify the core technologies of product-process co-evolution. Combining expert judgment with its results, we can clarify the technological co-evolution trajectory with mainstream as well as emerging core technologies. Reflecting these in the assessment process of a technology radar, we could improve reliance of the technology assessment process and technology portfolio. From the academic perspective, our research provides a point where the co-evolution theory encouners technology intelligence methods. Practically, strategic capability of future-preparedness and strategic management could improve by adopting our method based on our example of co-evolution of semiconductor product and process technologies.

• The Korean Journal of Applied Statistics
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• v.21 no.5
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• pp.845-854
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• 2008

Survey reports of election opinions consist of numerous cross-tabulations between socio-demographic variables and political opinions including preferred candidates. Since socio-demographic variables are related each other, duplicate interpretations arise. The aim of this study is twofold: The first is to separate the effects of socio variables such as education, occupation and income from the effects of demographic variables such as region, sex and age. The second is the visualization of multiple cross-tabulations in low-dimensional space by extended doubling technique of correspondence analysis. Survey researchers may get some help from this study to present their survey results more lucidly and visually.

• Journal of the Korean association of regional geographers
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• v.19 no.2
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• pp.362-374
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• 2013

ICTs(Information and Communication Technologies) have changed the ways of social activities and communications, and in the process, online and offline spaces have been thought of as binary spaces in which online spaces substitute and erode offline spaces. The aim of this study is to explore how urban space where local social activities and communications are performed is constructed in terms of timespace through the intersection of online and offline communications and how the urban space is 'remediated' through online spaces. For this, the study looks at the case of a workshop on 'locality education' held at the Yeungnam University Museum in January 2013. Criticizing the dichotomist viewpoint that increasing in communications through online spaces results in the expansion of 'absent presence' or 'placelessness' in offline spaces, the study argues that online spaces remediating offline spaces are spaces not transcending the timespace constraints of the offline spaces but rather reflecting the spatial, temporal, material, social, cultural environments of urban space and place.

• Journal of the Economic Geographical Society of Korea
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• v.26 no.2
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• pp.137-154
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• 2023

The purpose of this study is to find ways to utilize public-private partnerships from the perspective of governance in order to effectively promote urban regeneration projects and establish a business structure. The results of the study are summarized as follows. First, from the perspective of governance, the types of public-private partnerships in urban regeneration projects can be classified into central government-led, local government-led, private business-led, and local residents and community organizations-led. Second, it is confirmed through overseas case analysis that developed countries are effectively promoting urban regeneration projects through the formation of various public-private partnerships. Third, as a way to utilize public-private partnerships in Korean urban regeneration projects, it was proposed to diversify the types and size of urban regeneration projects, design a system to utilize various public-private partnerships, use cross-assistance methods, and form social capital necessary for transparent and effective private partnerships.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.67-77
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• 2007

This study deals with the traffic accidents at the unsignalized intersections in Cheongju. The purpose is to analyze the characters and the relations between road environmental factors and traffic accidents. The correlation analyses among the above factors show that the accidents are strongly related to traffic volumes and sight distances in 3-legged, and the cross angles, maximum vertical grades and sight distances in 4-legged unsignalized intersections. Also the multiple linear and nonlinear regression analyses represent that the accidents in the 3-legged increase as the traffic volume and the number of double stop-lines increase, and that the accidents in the 4-legged increase as the cross angle approaches to the 90 degree and decrease as the maximum vertical grade increases. It could be expected that this results give the good implications to the future intersection improvement projects in Cheongju.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.424-430
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• 2021

Determining the cause of a traffic signal violation is difficult if the drivers' claims are contradictory. In this study, the process of identifying signal violations using a simulation was presented based on cases. First, statements from the driver or witness whose cause of the signal violation is unclear were excluded. Second, the final position, final location, damaged area, steering status, braking status, and road surface traces of the vehicle were collected. The impact point was investigated from the stop line. Third, simulation data were modified and entered until the collision situation of the accident vehicle and the final stop position were met. Fourth, if the simulation results were consistent with the crash situation, the facts were verified by cross-validation to conform to the driver's statement. The results of the simulation showed that the Lexus entered the left turn signal in the intersection at approximately 55 km/h. In comparison, the Sonata driver saw the vehicle straight ahead at the intersection, entered the 72 km/h intersection, and collided with the Lexus. Therefore, the Sonata was identified as a signal violation, and the claims of the Sonata driver, witnesses, and police were contradictory.

• Korean Journal of Social Welfare
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• v.65 no.4
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• pp.195-220
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• 2013

The purpose of this study is to discover the context and pattern of turnover social workers have experienced. To achieve this purpose, researchers collected data from in-depth interviews with seven social workers who have experiences of turnover and analysed the data using context-pattern analysis method. Research findings are composed of individual context-pattern analysis and integrated context-pattern analysis. In individual context-pattern analysis, researchers mixed time-dimension(before turnover/on the process/after turnover) and level-dimension(experienced phenomenon/meaning of experiences/context connected with phenomenon and meaning) and analysed the context of every stages and serial pattern. Also, we connected with each contexts and patterns and integrated the context-pattern of turnover. Integrated context-pattern structure is divided for four areas; organization before turnover, organization after turnover, social worker as a stakeholder of turnover, and network of social worker. Based on the results of the study, administrative recommendations were suggested in order to manage the turnover of social workers in social work fields.

• Tunnel and Underground Space
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• v.9 no.3
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• pp.185-193
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• 1999

This paper presents results of dynamic analysis for a bridge in intersection part of two tunnels subjected to moving vehicle load. Since such a bridge system is very unusual due to the fact that it is located in tunnel, the dynamic characteristics of the structure can not be assumed as conventional one. The structure investigated in this study it a reinforced concrete bridge in the intersection part of Namsan Tunnel-1 and Tunnel-2 in Seoul. It is supported by temporary steel structure which shall be constructed during the period of replacing lining in Tunnel-2. Dynamic analysis was carried out for the system using a finite element model constructed by general purpose FE program SAP2000. For this purpose, the structure, lining of tunnels, and surrounding rock were represented by finite elements, while the rock region it truncated and on its outer boundary viscous dampers were placed to simulate radiation of elastic waves generated tunnels. Several types of vehicle with various driving velocities were considered in this analysis. The FE model including vehicle loadings was verified by comparing calculated peak particle velocity with the measured one. From the analysis, the impart factor for the bridge was estimated as 0.21, which indicates that the use of upper bound for the impact factor in design code is reasonable for this kind of bridge system.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.151-171
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• 2023

This study analyzed farmer's responses to the pilot project in advance of the nationwide expansion of the farm-customized early warning service for weather risk management by conducting a survey among all farmers who received text messages of this service. We analyzed not only the satisfaction of farmers with the early warning service, but also the effectiveness of the service in preventing agrometeorological disasters through cross-tabulation analysis of survey results. More than 330 farmers participated in the survey, and more than 60% of the respondents said that they had prevented or mitigated crop disasters by using the early warning service. The cross-tabulation analysis showed that farmers who perceived the field-specific weather information of the early warning service to be more accurate than the weather forecast were statistically significantly more likely to prevent crop disasters than those who did not. According to our case study, farmers who grew open field fruit crops were particularly sensitive to weather information and confirmed that early warning services, along with disaster prevention facilities, were effective in preparing for freezing and frost injury that had been occurring frequently under the influence of climate change. This study is significant in that it is the first to systematically analyze the effectiveness of the farm-customized early warning service for weather risk management based on extensive surveys. It is expected to contribute to exploring ways to develop the service ahead of the nationwide expansion of the early warning service in the near future.