• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.78-83
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• 2000

In this study, CT specimens were prepared from AST SA516 Gr. 70 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at 25$^{\circ}C $, -60$^{\circ}C $, -80$^{\circ}C $ and -100$^{\circ}C $ and in the range of stress ratio of 0.05, 0.3 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range ${\delta} K_{th}$ in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\delta $K in the stable of fatigue crack growth (Region II) were increased in proportion to descending temperature. It was assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN -$\delta $K in Region II, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It was assumed that the fatigue crack growth rate da/dN is rapid in proportion to descending temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.220-223
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• 2001

In this study, CT specimens were prepared hem ASTM SA516 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$, -3$0^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, -l$0^{\circ}C$ and -l2$0^{\circ}C$ and in the range of stress ratio of 0.1, 0.3 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range ΔK$_{th}$ in the early stage of fatigue crack growth ( Region I ) and stress intensity factor range ΔK in the stable of fatigue crack growth ( Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN - ΔK in Region II, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region H and the cryogenic-brittleness greatly affect a material with decreasing temperature.e.greatly affect a material with decreasing temperature.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.326-331
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• 2001

In this study. CT specimens were prepared from ASME SA5l6 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$, -3$0^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, -10$0^{\circ}C$ and -12$0^{\circ}C$ in the range of stress ratio of 0.1 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range ΔKsub/th/ in the early stage of fatigue crack growth ( Region I) and stress intensity factor range ΔK in the stable of fatigue crack growth ( Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da.dN -ΔK in RegionII, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.

• Journal of the Korean association of regional geographers
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• v.20 no.1
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• pp.1-15
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• 2014

This study aims to analyze empirically the scale of region that has been covered in "The Journal of the Korean Geographical Society(대한지리학회지)" and "The Journal of the Korean Association of Regional Geographers(한국지역지리학회지)" over the last 20 years. Generally speaking, it was found that "The Journal of the Korean Geographical Society" has published a relatively more number of articles with larger scale of region and "The Journal of the Korean Association of Regional Geographers" has published more articles with smaller scale of region than the counterpart journal. Also, this study has revealed that the ratio of the studies in both journals utilizing both town/village scale(읍 면 스케일) and city/county scale(시 군 스케일) has increased continuously with marginal fluctuations. On the other hand, the ratio of the studies in both journals combining single metropolis/province scale(시 도 스케일), multiple metropolis/province scale(시 도보다 큰 스케일), and state scale(국가 스케일) has decreased continuously in general. In sum, this study is expected to offer useful data as well as future research direction to the Korean geographers.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.323-331
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• 2021

The relevance of the study implies the need to explain the main determinants of environmental policy, allowing countries to converge on a common working basis. The purpose of the research is to explore ways in which the environmental aspects of EU regions and territories can be shaped to apply to domestic environmental policy. A total of 997 representatives from the Ukrainian UTCs, who are involved in local environmental policy, participated in the survey. Results of the research. A hierarchy of regional environmental policy objectives has been identified. Three key principles of eco-policy development have been distinguished. The means of the innovative approach strategy implementation have been outlined (formation of the regional market of environmental services; organization of interaction between environmental agencies and market structures; establishment of environmental funds which finance environmental activities; implementation of the "collateral return" system; formation of a system of benefits and loans to enterprises that successfully implement the environmental policy). The means of the prognostic approach implementation strategy to the development of the region's environmental policy have been determined (the use of an orderly and successful long-term strategy of economic development of the region; obligatory consideration in the mechanisms strategy aimed at improvement of environmental management system of the region, interbranch impact of the projects implemented on the region's ecological situation; taking into consideration the economic and geographical peculiarities of the region, the necessary infrastructure, issues of the territorial location of the large enterprises in the region and their impact on the environment). The means of the traditional approach strategy implementation have been outlined (activity programs focused on solution of specific problems, rather than on the implementation of measures for environmental restoration and enhancement; nature conservation problems have interbranch, interdepartmental character due to unity of the region's ecosystem; tracking complexity of changing conditions (water basins, woodlands, air-mass transport), regional boundaries generally do not coincide with natural ecosystems boundaries). The practical significance of the study lies in providing recommendations for the implementation of certain aspects of Ukrainian UTC's environmental policy.

• Journal of the Korean earth science society
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• v.38 no.3
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• pp.182-193
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• 2017

A typical snowfall pattern occurs over the east coastal region of the Korean Peninsula, known as the Yeongdong region. The precipitation over the Yeongdong region is influenced by the cold and dry northeasterly wind which advects over warm and moist sea surface of the East Sea of Korea. This study reveals the influence of large-scale factors, affecting local to remote areas, on the mesoscale snowfall system over the Yeongdong region. The National Centers for Environmental Prediction-Department of Energy reanalysis dataset, Extended Reconstructed sea surface temperature, and observed snowfall data are analyzed to reveal the relationship between February snowfall and large-scale factors from 1981 to 2014. The Yeongdong snowfall is associated with the sea level pressure patterns over the Gaema Plateau and North Pacific near the Bering Sea, which is remotely associated to the sea surface temperature (SST) variability over the North Pacific. It is presented that the relationship between the Yeongdong snowfall and large-scale factors is strengthened after 1999 when the central north Pacific has warm anomalous SST. These enhanced relationships explain the atmospheric patterns of recent strong snowfall years (2010, 2011, and 2014). It is suggested that the newly defined index in this study based on related SST variability can be used for a seasonal predictor of the Yeongdong snowfall with 2-month leading.

• Structural Engineering and Mechanics
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• v.88 no.1
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• pp.13-23
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• 2023

Seismic risk assessment studies are one of the most crucial instruments for mitigating casualties and economic losses. This work utilizes fragility curves to evaluate the seismic risk of single-story precast buildings, which are generally favored in Marmara's organized industrial zones. First, the precast building stock in the region has been categorized into nine sub-classes. Then, seven locations in the Marmara region with a high concentration of industrial activities are considered. Probabilistic seismic hazard assessments were conducted for both the soil-dependent and soil-independent scenarios. Subsequently, damage analysis was performed based on the structural capacity and mean fragility curves. Considering four different consequence models, 630 sub-class-specific loss curves for buildings were obtained. In the current study, it has been determined that the consequence model has a significant impact on the loss curves, hence, average loss curves were computed for each case investigated. In light of the acquired results, it was found that the loss ratio values obtained at different locations within the same region show significant variation. In addition, it was observed that the structural damage states change from serviceable to repairable or repairable to unrepairable. Within the scope of the study, 126 average loss functions were presented that could be easily used by non-experts in earthquake engineering, regardless of structural analysis. These functions, which offer loss ratios for varying hazard levels, are valuable outputs that allow preliminary risk assessment in the region and yield sensible outcomes for insurance activities.

• Journal of Periodontal and Implant Science
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• v.46 no.6
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• pp.396-404
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• 2016

Purpose: The aim of this retrospective study was to determine the association between dental implants in the posterior region and traumatic occlusion in the adjacent premolars, using data collected during from 2002 to 2015. Methods: Traumatic occlusion in the adjacent premolars was assessed by examining clinical parameters (bleeding on probing, probing pocket depth, fremitus, and tooth mobility) and radiographic parameters (loss of supporting bone and widening of the periodontal ligament space) over a mean follow-up of 5 years. Clinical factors (gender, age, implant type, maxillary or mandibular position, opposing teeth, and duration of functional loading) were evaluated statistically in order to characterize the relationship between implants in the posterior region and traumatic occlusion in the adjacent premolars. Results: The study inclusion criteria were met by 283 patients, who had received 347 implants in the posterior region. The incidence of traumatic occlusion in the adjacent premolars was significantly higher for splinted implants (P=0.004), implants in the maxillary region (P<0.001), and when implants were present in the opposing teeth (P<0.001). The other clinical factors of gender, age, and duration of functional loading were not significantly associated with traumatic occlusion. Conclusions: This study found that the risk of traumatic occlusion in the adjacent premolars increased when splinted implants were placed in the maxillary molar region and when the teeth opposing an implant also contained implants.

• Journal of the Korean association of regional geographers
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• v.19 no.3
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• pp.416-435
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• 2013

Pyeongtaek port, opened in 1986, has played a role as an international trading port. Pyeongtaek city which is a hinterland with Pyeongtaek port has both landscape of city and rural area. Aims of this study is investigating the regional change of Pyeongtaek city according to the opening of Pyeongtaek port: the change in population and land value by the average distance(27.3km) between Pyeongtaek port and each region and the change in industry and regional industry with location quotient of region. The increasing rate of population and people who work for industry showed an aspect of rising as a place locates near Pyeongtaek port, yet the increasing rate of land value showed little differences. In short, as the area is closer to Pyeongtaek port, the number of population and employees are higher. Yet, the increasing rate of the land value showed little difference. The study showed that manufacturing industry is specialized in rural region(eup myeon region), and tertiary industry is specialized in urban region(dong region) of Pyeongtaek city according to location quotient.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.279-290
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• 2000

The purpose of this study is to suggest the analytical framework for a spatial structure of a tourism destination master plan by the two types of the tourism development models: Tourist attraction System Model and Tourism Destination Region Design Model. The resort development plan is introduced as a planning tool for regenerating the eastern Pusan regions, but the economic and environmental impacts and the sociocultural dilemma accompanied by the development should be fully considered before launching the business. The development plan announced currently is traced and examined in comparison with the upper-leveled and related plans. The Tourist Attraction System Model based on the systems theory is applied to the designated regions. The Tourism Destination Region Design Model then is applied for analyzing the components of each region on the master plan. The results of the findings suggest that the tourism destination plan is basically different from a general master plan on the physical comprehensive plan, the destination is recognized as a subsystem of the whole tourism system, and thus tourism destination plan is considered as a spatial arrangement of tourism facilities and the inter- and intra-circulation.