• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.6
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• pp.923-929
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• 2003

In this paper, an analysis of fatigue crack growth behavior from a statistical point of view has been carried out. Fatigue crack growth tests were conducted on sixteen pre-cracked compact tension (CT) specimens of the pressure vessel (SPV50) steel in controlled identical load and environmental conditions. The assessment of the statistical distribution of fatigue crack growth experimental data obtained from SPV50 steel was studied and also the correlation of the parameter C and m in the Paris-Erdogan law was discussed. The probability distribution function of fatigue crack growth life seems to follow the 3-parameter Weibull. The fatigue crack growth rate seems to follow the 3-parameter Weibull and the log-normal distribution. The coefficient of variation (COV) of fatigue crack growth life was observed to decrease as the crack grows. Fatigue crack growth rate data shows a normal distribution for both m and logC. A strong negative linear correlation exists between the coefficient C and the exponent m.

• Journal of Korea Planning Association
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• v.54 no.3
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• pp.15-26
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• 2019

The development of science and transportation technology leads to the increase of inter - city networks that play an important role in urban growth. Overall, numerous studies based on network theory pay attention to positive effects of urban network on urban growth. However, some studies have pointed out the negative effects of inter-city interactions such as straw effects. This implies that the network between cities may not be positively correlated with urban growth, and that the direction of the influence may vary from a certain threshold, such as the marginal utility curve. In this context, the purpose of this study is to measure the impacts of network with central city on urban growth in the capital region and examine the relationship between urban network and growth. Two multiple regression models are employed with changes in population and employment as dependent variables. The urban network index and other control variables are used as independent variables. Especially, the urban network indexes are used in quadratic forms to examine non linear relations with urban growth such U-shape or an inverted U-shape. The results show that the relationships between networks with the central city and urban growth are not a simple linear, and the influence can be changed from the critical point.

• Proceedings of the Korea Crystallographic Association Conference
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• 2000.05a
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• pp.32-32
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.220-220
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• 2005

• Journal of Korea Game Society
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• v.4 no.4
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• pp.25-30
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• 2004

Recently, it is increasing a users requiring actually and a variety of service due to a growth of wet based technique and network technique. In services, the interest in web and mobile contents domain is increasing rapidly. The most contents supported point or a E-Money as result of contents's usage. But, the point system be in name only due to a lack of a contents using a point or a related service. As a solution for this problem, this paper designed a supported system that integrated a point system supporting others contents and can associated to a game using that point. we made a simple game and supporting contents in web for simulating the designed system. Also, we realized the mobile system for communicating a data causing in web.

• Journal of the Korean housing association
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• v.23 no.4
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• pp.11-18
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• 2012

The amount of energy consumption in the buildings is approximately 20% of domestic energy consumption. The Carbon Point Program have been published on reduction of greenhouse gas emission in buildings under the paradigm of 'Low Carbon Green Growth'. This study focuses on the effect of 'Carbon Point Program' for residential buildings in Daegu. The amount of electricity and waterwork consumption and information of households were investigated to analyse the effect of carbon point program. The samples are situated in Deagu and are apartment in Bukgu and Suseonggu. The $CO_2$ emission is analysed by factors of energy resource and household organization between before participating and after participating in Carbon Point Program. The participation type has a difference of voluntary participation in Suseonggu and passive participation in Bukgu. Based on this investigation, average amount of $CO_2$ emission was reduced from voluntary participation households but all of them did not. To promote the effect of Carbon Point Program, this study proposes that needing the plans to raise will and activity of reducing carbon and to help participation which have disadvantage against achieving reduction.

• Journal of Korea Multimedia Society
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• v.24 no.11
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• pp.1518-1525
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• 2021

Due to the growth of VR industry and rise of digital twin industry, the importance of implementing 3D data same as real space is increasing. However, the fact that it requires expertise personnel and huge amount of time is a problem. In this paper, we propose a system that generates point cloud data with same shape and color as a real space, just by scanning the space. The proposed system integrates 3D geometric information from lidar and color information from stereo camera into one point cloud. Since the number of 3D points generated by lidar is not enough to express a real space with good quality, some of the pixels of 2D image generated by camera are mapped to the correct 3D coordinate to increase the number of points. Additionally, to minimize the capacity, overlapping points are filtered out so that only one point exists in the same 3D coordinates. Finally, 6DoF pose information generated from lidar point cloud is replaced with the one generated from camera image to position the points to a more accurate place. Experimental results show that the proposed system easily and quickly generates point clouds very similar to the scanned space.

• Water Engineering Research
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• v.7 no.1
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• pp.1-8
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• 2006

Recently, the population growth and agricultural development are rapidly undergoing in the South-West Texas. The junction of three river basins such as Lavaca river basin, Colorado-Lavaca Coastal basin and Lavaca-Guadalupe Coastal basin, are interesting for non-point and point source pollutant modeling: Especially, the 2 basins are an intensively agricultural region (Colorado-Lavaca Coastal/Lavaca-Guadalupe Coastal basins) and several cities are rapidly extended. In case of the Lavaca river basin, there are many range land. Several habitat types wide-spread over three relatively larger basins and five wastewater discharge regions are located in there. There are different hazardous substances which have been released. Total nutrient loads are composed of land surface load and river load as Non-point source and discharge from wastewater facilities as point source. In 3 basins region, where point and non-point sources of poll Jtion may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to how to assess and control the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern as non-point source with water quality related to pesticides, fertilizer, and nutrients and as point source with wasterwater discharge from cities. The GIS technique has been developed to aid in the point and non-point source analysis of impacts to natural resource within watershed. This project shows the losses in $kg/km^2/year$ of BOD (Biological Oxygen Demand), TN (Total Nitrogen) and TP (Total Phosphorus) in the runoff from the surface of 3 basins. In the next paper, sediment contamination will show how to evaluate in Estuarine habitats of these downstream.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.165-183
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• 1987

The purpose of this study is to investigate the cephalo-facio-dental relationships in the craniofacial complex and their changes with age, and to use them for diagnostic and treatment purposes in the orthodontics The author studied on the changes of the cephalo-facio-dental relationships, using serial lateral cephalometric roentgenograms of 46 boys and 47 girls aged from 6 to 11 years of normal Korean children Following results were obtained 1 Means and Standard deviation of Korean children were obtained. 2 In the evaluation of the craniofacial vertical proportions, lower anterior face was larger than the upper, and upper posterior face was larger than the lower at all ages 3 The growth change was more prominent in the anterior craniofacial vertical proportion than in the posterior, and growth increment in the upper anterior facial height dimension was larger than m the lower anterior. 4 In the evaluation of the craniofacial horizontal proportion, ANS, Pog, Go and 6 were all situated posterior to their reference ares, and point B was always situated anterior to the arc passing by point A. 5. Anteroposterior growth change was the most prominent in the mandible, and there was no significant difference between the horizontal growth increment in the cranial base and that in the maxilla 6 Growth increment in the horizontal direction was larger in the mandibular apical base than in the maxillary apical base 7 The upper central incisor and the upper first molar were gradually anterior positioned against their reference ares with age increase 8 The length of mandibular corpus was larger than that of cranial base from the seven years old, and the difference was increased as the age increased 9 With age, there was slight difference in the angular relationships formed by craniofacial reference planes and axial inclinations of upper and lower permanent teeth.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.181-187
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• 2018

With a view to deepening the research stream on the factors positively influencing the export growth and the employment increase of South Korean small and medium companies, this research has developed the research model about the impact of small and medium companies' external technology R&D collaboration network heterogeneity on their export growth and employment increase, and has empirically tested the research model with the 2,200 data collected from the small and medium companies in the South Korea. This study illuminates the two points from the empirical testing results. One point is that small and medium companies' external technology R&D collaboration network heterogeneity significantly and positively influences their employment increase from technology development. The other point is that small and medium companies' export growth from technology R&D partially mediates the impact of the external technology R&D collaboration network heterogeneity on their employment increase from technology R&D.