• Journal of the Korea Society for Simulation
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• v.24 no.1
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• pp.35-43
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• 2015

This research proposed a new method to evaluate the objective validity to launch smart transportation services that various stakeholders are complicatedly inter-connected. First of all, we have designed the fundamental business model to form the smart transportation services and defined the stakeholders taking part in the services. Also, the criteria to evaluate the economical validity has been proposed based on the relationship among stakeholders. Especially, in the case EV drivers and charging service providers, the economical validity depends on the scale of spreading. Therefore, we have compared the two extreme scenarios, the poor and stable level of EV spreading. According to the result, it may be said that EV drivers and charging service providers cannot be guaranteed the economical validity due to the burden of initial investment. On the contrary to this, suppliers of EV and charging gears may secure more than a certain level of profit. In addition, the government may have great profit due to reducing the CO2 emission and cost for importing energy sources. Therefore, it is needed to enhance the level of supporting EV drivers and charging service providers at the first stage. Also, the impact of the ratio of EV and charging service stations on the economical validity of smart transportation should be further investigated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.362-371
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• 2019

The purpose of this study is to recognize kindergarten teachers' experiences of child violence for identifying the site's needs for the implementation of preventive education in early childhood and to provide basic data on child violence. To this end, nine teachers were interviewed in-depth. From the study results, first, child violence-related child behavior, which usually occurs in kindergartens, includes physical assault, aggression, verbal violence, threats and threats, and bullying. Second, teachers usually use direct intervention laws in cases of child violence, but were finding it difficult to intervene properly with many tasks or high teacher-to-child ratios. Teachers recognized the need for lower teacher-to-child ratios and placement of each class burden. Third, teachers were aware of the need for prevention education for child violence targeting infants, and instigated the following appropriate interactions immediately after problem behavior occurred: large group activities, specific multimedia education data and parent education. Fourth, teachers are concerned about the possibility of problem behavior being learned and imitated through education in the implementation of prevention education for children's violence. Therefore, this study proposed the need to develop various teaching methods that could be applied to infant education sites, focusing on the types of child violence-related problem behaviors that occur in kindergartens.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.4
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• pp.1-15
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• 2003

Recently, urban information system(UIS) has been developed and utilized by local governments in Korea and has become a key means of urban informatization of local governments. When UIS is conducted only for FM oriented internal utilization regardless of its cost-efficiency, however, its cost-benefit structure could be distorted seriously. The study utilizes benefit cost analysis technique and applied the technique to a model case of Chungju UIS selected by National GIS team. Chungju City developed its GIS for the management of roads and urban planning in 1993. At its beginning, the system was an efficient model with relatively strong cost-benefit structure and could produce positive net benefit 10 years' after its construction. When the city began to develop its facility management with the financial assistance from central government in 1998, however, its cost-benefit structure became distorted. As a result, it is delayed for the UIS to produce positive net benefit until the year of 2015. Using benefit cost ratio, discount rate and Mobile GIS, the study also conducts a sensitivity analysis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.6
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• pp.1053-1061
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• 2017

The study is concerned with providing the improvement method on making a reasonable and scientific decision on the damages accrued from the bid rigging in the construction work. According to the review on the precedent studies and decision cases on the damages caused by bid rigging, the representative problems include the insufficiency of the classification system on the damage calculation method and the omission of the necessary stage in the damage determination process. First, the improved classification system on calculating the damages caused by bid rigging is presented with the application to the bid rigging in the construction work by adding the ratio factor in addition to the damage calculation parameters such as price and cost. Second, the standard procedures organized with six stages is presented as the process required for determining the damages if the indemnification for bid rigging is claimed. The study becomes the foundation for resolving the problem with the undue burden on a party and for preventing the opportunity loss by resolving a dispute early through the improvement classification system and standard procedures presented in the study.

• The Journal of the Korea Contents Association
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• v.15 no.7
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• pp.314-321
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• 2015

The purpose of this study is to investigate musculoskeletal symptoms and job stress of physical therapists in their 20s who are responsible for therapeutic exercise and to understand the correlation between the two. This study conducted a research on 144 subjects based on the measurement tools provided by national institution. The results are as follows. Many subjects were experiencing musculoskeletal symptoms and disorder in their hands/wrists/fingers, shoulders, and waist with high proportionate of subjects experiencing the symptoms and disorder in their right hand/wrist/finger. Among job stress, job environment, job requirement, and compensation had significantly positive correlation with physical burden(r=.297~.392, p=.000). In particular, shoulder pain intensity has significantly positive correlation with job requirement, duration of pain in hand, wrist, and fingers as well as workplace culture(r=.331~.478, p=.003~.009) which indicates that musculoskeletal symptoms are some what correlated with job stress. Based on this study, it is necessary to show more concern and make an effort to manage musculoskeletal symptoms and job stress.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.461-472
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• 2010

This paper investigates the behavior of precast concrete (PC) shear walls with a new vertical connections for a fast remodeling construction. The C-type vertical connections for the PC wall systems are proposed for transfer of bending moment between top and bottom walls in the vertical direction while a shear key in the center of wall is prepared to transfer shear forces by bearing action. The proposed vertical connections allows easy fabrication thanks to slots at the edges of wall in opposite directions. The plane PC wall systems subject to lateral load are compared with ordinary wall systems by investigating the effects of connection on the stiffness, strength, ductility, and failure modes of whole systems. The load-displacement relationship and influence of premature failure of connections are examined. The experimental test showed that the longitudinal reinforcing steel bars placed at the edges of walls yielded first and the ultimate deformation were terminated due to premature failure of connections. The diagonal reinforcements for efficient shear transfer in the walls were not effective. The strength and deformation obtained through the section analysis were generally in agreement with the experimental data, and indicated that. Gap opening contributed to the deformation behavior more than any other factors.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.37-46
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• 2001

Pile load tests were carried out to investigate the contribution of the pile cap to the carrying capacity of a pile group and load transfer characteristics of piles in the group. A group of 24 piles$(4 \times6 array)$ of 92.5mm diameter steel pipe were installed to the depth of 3m fron the ground surface, the top of weathered rock. A maximum load of 320ton was applied to the pile cap, $1.5\times2.3m$, in contact with the ground surface. At the maximum load of 320ton, the pile cap has carried 22% of the total load. Average ultimate capacity of pile in the pile group was estimated to be 16.4ton, substantially higher than that of single pile, installed at the corner and tested before pile cap construction. For the same magnitude of settlement, the pile in the center carried less load than the pile at the perimeter due to strain superposition effect. Piles in the group showed almost constant contribution(approx. 60%) of side friction to the total capacity for all of the loading stages, while that of single pile decreased from 82% to 65%.

• Journal of KIISE:Databases
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• v.28 no.2
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• pp.217-232
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• 2001

본 논문에서는 시계열 데이터베이스에서 정규화 변환을 지원하는 서브시퀀스 매칭 알고리즘을 제안한다. 정규화 변환을 시계열 데이터 간의 절대적인 유클리드 거리에 관계 없이, 구성하는 값들의 상대적인 변화 추이가 유사한 패턴을 갖는 시계열 데이터를 검색하는 데에 유용하다. 기존의 서브시퀀스 매칭 알고리즘을 확장 없이 정규화 변환 서브시퀀스 매칭에 단순히 응용할 경우, 질의 결과로 반환되어야 할 서부시퀀스를 모두 찾아내지 못하는 착오 기각이 발생한다. 또한, 정규화 변환을 지원하는 기존의 전체 매칭 알고리즘의 경우, 모든 가능한 질의 시퀀스 길이 각각에 대하여 하나씩의 인덱스를 생성하여야 하므로, 저장 공간 및 데이터 시퀀스 삽입/삭제의 부담이 매우 심각하다. 본 논문에서는 인덱스 보간법을 이용하여 문제를 해결한다. 인덱스 보간법은 인덱스가 요구되는 모든 경우 중에서 적당한 간격의 일부에 대해서만 생성된 인덱스를 이용하며, 인덱스가 필요한 모든 경우에 대한 탐색을 수행하는 기법이다. 제안된 알고리즘은 몇 개의 질의 시퀀스 길이에 대해서만 각각 인덱스를 생성한 후, 이를 이용하여 모든 가능한 길이의 질의 시퀀스에 대해서 탐색을 수행한다. 이때, 착오 기각이 발생하지 않음을 증명한다. 제안된 알고리즘은 질의 시에 주어진 질의 시퀀스의 길이에 따라 생성되어 있는 인덱스 중에서 가장 적절한 것을 선택하여 탐색을 수행한다. 이때, 생성되어 있는 인덱스의 개수가 많을수록 탐색 성능이 향상된다. 필요에 따라 인덱스의 개수를 변화함으로써 탐색 성능과 저장 공간 간의 비율을 유연하게 조정할 수 있다. 질의 시퀀스의 길이 256 ~ 512중 다섯 개의 길이에 대해 인덱스를 생성하여 실험한 결과, 탐색 결과 선택률이 $10^{-2}$일 때 제안된 알고리즘의 탐색 성능이 순차 검색에 비하여 평균 2.40배, 선택률이 $10^{-5}$일 때 평균 14.6배 개선되었다. 제안된 알고리즘의 탐색 성능은 탐색 결과 선택률이 작아질수록 더욱 향상되므로, 실제 데이터베이스 응용에서의 효용성이 높다고 판단된다.

• Archives of design research
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• v.11 no.3
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• pp.187-196
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• 1998

This study is intended to suggest the method of text arrangement in order to enhance visual perception which would help darify its communication. One hundred subjects without restriction of gender and profession participated in each experiment :their reading time was measured by the 0.01 second. The Analysis of Variance(two-way ANOVA without interaction) was performed for each experiment and the p value was 0.0001 which implies that there was a strong consistency among test results. Based on the first results, it is found that there is a consistent relationship between type size and text line length, and the following discovery was made ; the most effective ratio of type size to line length is approximately 1 :8. Judging from the Second and Third results, it seems that the vertical text arrangement is most efficient for reading regardless of text line length. So to make same rreading direction is more important than to narrow down the eye moving distance between column and column for efficient visual flow. This research supports the view that considering efficient eye movement on text, it is important to understand the mentioned variables that affect visual interpretation.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.105-115
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• 2004

In developed and industrialized countries life expectancy has increased significantly over the past century. As a consequence, the proportion of elderly individuals in these countries has also enlarged with the resulting increased burden on health care providers. In many developing countries the problem of age related and other eye disorders has far outstripped the ability to manage them. Accordingly, the World Health Organization (WHO) has introduced an initiative: Vision 2020 - The Right to Sight, with the objective of eliminating preventable blindness by the year 2020. This paper reviews the broad range of conditions involving external and internal structures of the eye and also the effects of aging on visual functions. It is hoped that this will provide a stimulus for increased study of these disorders, improved clinical diagnosis, and an enhanced interest and role in contributing to the objectives of the WHO and the World Council of Optometry with respect to early diagnosis, prevention and management of the diseases and disorders of the eye that are more prevalent in old age.