• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2A
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• pp.261-271
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• 2006

Many uncertainties affecting to the structural behavior of prestressed concrete (PSC) bridges reinforced with the un bonded external tendons are analyzed on the basis of the analytical method introduced in the companion paper. Many design parameters, which must be considered in design procedure, such as friction slip at the deviators, number of deviators, time-dependent deformations of concrete, relaxation of tendon and influence of loading history in PSC bridges are reviewed, and a lot of valuable results are obtained through this parametric study. In advance, the structural responses according to the external tendon profiles are analyzed to grasp if an optimum tendon profile depends on the applied loading type, and the obtained results show that the most stable structural response is revealed when the locations of deviators are coincident with the loading points.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.391-405
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• 2005

Chemical and isotopic analysis for stream water, shallow groundwater, intermediate groundwater and deep groundwater was carried out to grasp hydrogeochemical characteristics of groundwater in the Heunghae area, Pohang city. Water type of stream water and shallow groundwaters is typified as Ca-Cl type, intermediate groundwater is $Na-HCO_3$, and deep groundwater is prominent in Wa-Cl type. $HCO_3^-\;and\;SiO_2$ in shallow groundwater are originated from weathering of silicate minerals, whereas those of deep groundwaters are resulted from weathering of carbonate minerals. Ca and Mg ions in both shallow and deep groundwaters are resulted from weathering of calcite and dolomite. $SO_4^{2-}$ in shallow groundwater is originated mainly from pyrite oxidation. As well depth increases, pH and TDS increase, but Eh and DO decrease. Alkali metal contents(K, Na, Li) increases as well depth increases, but alkali earth metal(Mg, Ca) and hi concentrations increase as well depth decreases. Anions, halogen elements(F, Cl, Br), and $HCO_3$ contents increase as well depth increases. The average stable isotope value of the groundwater of each depth is as follows; deep groundwater: ${\delta}^{18}O=-10.1\%o,\;{\delta}D=-65.8\%_{\circ}$, intermediate groundwater: ${\delta}^{18}O=-8.9\%_{\circ},\;{\delta}D=-59.6\%_{\circ}$, shallow groungwater : ${\delta}^{18}O=-8.0\%_{\circ},\;{\delta}D=-53.6\%_{\circ}$, surface water : ${\delta}^{18}O=-7.9\%_{\circ},\;{\delta}D=-53.3\%_{\circ}$ respectively.

• Fire Science and Engineering
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• v.27 no.6
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• pp.50-56
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• 2013

The radiation effects on the auto-ignition and extinction characteristics of a non-premixed fuel-air counterflow field were numerically investigated. A detailed reaction mechanism of GRI-v3.0 was used for the calculation of chemical reactions and the optically-thin radiation model was adopted in the simulations. The flame-controlling continuation method was also used in the simulation to predict the auto-ignition point and extinction limits precisely. As a result, it was found that the maximum H radical concentration, $(Y_H)_{max}$, rather than the maximum temperature was suitable to understand the ignition and extinction behaviors. S-, C- and O-curves, which were well known from the previous theory, were identified by investigating the $(Y_H)_{max}$. The radiative heat loss fraction ($f_r$) and spatially-integrated heat release rate (IHRR) were introduced to grasp each extinction mechanism. It was also found that the $f_r$ was the highest at the radiative extinction limit. At the flame stretch extinction limit, the flame was extinguished due to the conductive heat loss which attributed to the high strain rate although the heat release rate was the highest. The radiation affected on the radiative extinction limit and auto-ignition point considerably, however the effect on the flame stretch extinction limit was negligible. A stable flame regime defined by the region between each extinction limit became wide with increasing the fuel temperature.

• Journal of Fashion Business
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• v.6 no.6
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• pp.19-33
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• 2002

In the middle of economic and mental riches in the 21st century, the importance of well being and the pursuit of happiness are emerging as the new trend. Thus the lifestyle that values comfortable and practical naturalness and intrinsic merits has come to influence the human life rather than the old showing-off and formal desire. In addition to this, the spread of the five day week has given more leisure time, which has led to the increasing interest in health and leisure. The interest in sports has skyrocketed since the successful holding of the 2002 Korea and Japan World Cup event. All these changes to the lifestyle have contributed to the fusion of luxury wear and sports wear. As the result of the consumers in the 21st century having more classified and upgraded way of living thanks to the settlement of the above-mentioned lifestyle and the enlargement of the leisure sports culture, there has appeared the wellness kin, who value the importance of life and the nature and believe in the idea that they can reconstruct the environment in the way they can enjoy their lifestyle and pursue happiness. They favor healthy fashion items and think much of exercise, nutrition, and rest. They pursue the natural and comfortable style, whose ideas came from simple exercises such as health training and yoga and the easy and comfortable look observed at resorts. Their fashion style can be divided into three of fitness fashion, yoga fashion and resort fashion. First, the boxer fashion is characterized by the relaxing design and practicality. The major items of the fashion include running shirt-styled upper clothes, training pants, hooded shirts and sneakers. Simple and comfortable look should be induced from the combination of the items. Second, the yoga fashion was motivated by the comfortable yoga wear. It advocates stress-free spirit and comfortable and stable naturalism. Along with the advantages of the good feeling to wear and the functionality to help exercise better, the yoga fashion gives the wearer enough room to move around in, using the unique lines. Third, the resort wear refers to the kinds of clothes you tend to wear at the beach and the park. There are various kinds of the resort look; bathing suits, the beach wear you can wear with the bathing suit, the resort evening wear, the full-side look that you try on top of the bathing suit and is made of the same material of the bathing suit, and the marine look, the symbol of the summer. In short, the study attempted to investigate many trends occurring as the result of human recent increasing interest and concern in the quality of life, and the impacts of them on the fashion world. This kind of research that examines the background of the times and society will help to grasp with the fashion trends of the present and the future. And more studies should be conducted on the development of new and original design in clothes fashion, which reflects the characteristics identified in this kind of research.

• Journal of Fashion Business
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• v.2 no.4
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• pp.93-101
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• 1998

Knit products which had been limited only to underwear, recently became popularized, fashionized and highly classified covering even outer garments such as sportswear like golfwear, woman's dress, and man' s suit. As fashion cycle is getting shorter and the more a nation advanced prefers knit to woven fabrics knit industry has a very bright prospect, particularly woman's knit which is sensitive to fashion can be said as a fashion product with high value added. This study is to grasp the physical properties of stitch which are fundamental to the development of knit products. For this purpose, 2/20s of 100% wool were woven by the author of this study to basic plain stitch, rib stitch, varied transfer stitch, and float stitch on a SEMASEIKI cross knitter 7G to test the physical properties, and the result was as follows; 1. As for the relation between knit stitch and rate of extension recovery, rate of extension recovery was higher in the course direction than in the wale direction of three stitches except transfer stitch; rib stitch showed the highest rate of extension recovery in the course direction while float stitch showed the highest rate of extension recovery in the wale direction. 2. As for the relation between knit stitch and bursting strength elastic rib stitch showed higher bursting strength to indicate elasticity is an important factor of bursting strength and float stitch showed higher bursting strength too to indicate that the floating yarn on the surface plays a role of support. 3. As for the relation between knit stitch and air permeability perforated transfer stitch showed the lowest air permeability to prove that the size of perforation affects on the air permeability a great deal. 4. As for the relation between knit stitch and warmth retaining rib stitch through two lined needle bar showed the highest degree. The reason the warmth of perforated transfer stitch didn't decrease much was because the perforation wasn't big enough and content of air increased from the unevenness of the perforated parts through stitch variation. Based upon this result, each stitch can be characteristically summarized as follows; plain stitch showed a stable condition of knit cloth in four kinds of physical property test. And rib stitch is proper to tighten the edge of sleeve or clothe making use of its excellent extension recovery and to make socks for the highest bursting strength and warmth retaining. In the case of transfer stitch, seasonable designs can be taken by controlling the size of loop. Considering the pleasantness, underwear should be made of stitches with good air permeability float stitch was revealed to have color and pattern effects and a great bursting strength. This study has limitations in the aspect that it dealed with a small part of various knit stitches and the items of physical property test were not enough. The author of this study hopes that further studies would make deeper understandings about knit stitch based on more varied stitches and physical property tests ultimately to contribute to the development of fashionable designs proper to maximize the usage, function and originality.

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.102-110
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• 2009

This study examined the halophyte community and soil analysis according to habitat in representative 18 salt marshes of southern and western coasts of Korea from July 2006 to April 2008 and suggested basic materials for vegetational restoration of these aras. First, the survey area was classified into coastal and estuarine marshes. Then, the coastal marshes were classified into clay marsh, sand gravel marsh, and sand marsh, and the esturarine marshes, into salt swamp and estuary marsh. Major plant communities according to habitat pattern were Phragmites communis, Carex scabrifolia, and Suaeda japonica community in the clay marsh; Phragmites communis, Zoysia sinica, Carex scabrifolia, Salicornia herbacea, Artemisia fukudo, Suaeda martima community in the sand gravel marsh; Elymus mollis, Carex kobomugi, and Vitex rotundifolia community in the sand mars; Phragmites communis, Zoysia sinica, Suaeda martima, and Carex scabrifolia community in the salt swamp, and Suaeda japonica, Phragmites communis, Carex scabrifolia, and Suaeda asparagoides community in the estuary marsh. The soil environment of halophyte community area showed a difference to soil and halophyte community according to habitat characteristics of halophyte. Thus, to restore salt mashes in the coast area, it is advantageous for the stable settlement, germination, and growth of halophyte to grasp physical and physicochemical characteristics of habitat soil in the salt marshes, to select halophyte suitable to these habitat conditions, and to expand gradually in the natural vegetation area after transplantation.

• The Korean Journal of Archival Studies
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• no.10
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• pp.145-194
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• 2004

Church archives are the evidential instruments to remember church activity and important information aggregate which has administrative, legal, financial, historical, faithful value as the collective memory of church community. So it must be managed necessarily and the management orders are based on the Bible. The western churches which have a correct understanding about the importance of church records and management order have taken multilateral endeavor to create, manage church archives systematically. On the other hand, korean churches don't have the records management systems. Therefore, Records created in individual church are mostly managed unsystematically and exist as 'backlogs', finally, they are destructed without reasonable formalities. In those problems, the purpose of this study is to offer the way of records classification and disposition instrument with recognition that records management should be done from the time of creation or previous to it. As a concrete device for them, I tried to embody the function-based classification method and disposal schedule. I prefer the function-based classification and disposal schedule to the organization and function-based classification to present stable classification and disposal schedule, as we can say the best feature of the modern organization is multilateral and also churches have same aspect. For this study, I applied DIRKS(Designing and Implementing Recordkeeping Systems) manual which National Archives of Australia provide and guidelines in ICA/IRMT series to construct the theory of the function-based classification in individual churches. Through them, it was possible to present a model for preliminary investigation, analysis of business activity, records survey, disposal schedule. And I took an example of 'Myong Sung Presbyterian Church' which belong to 'The Presbyterian church in Korea'. I explained in detail codifying process and results of preliminary investigation in 'Myong Sung Presbyterian Church', analysis of business activity based on it, process of presenting the function-based classification and disposal schedule got from all those steps. For establishing disposal schedule, I planned 'General Disposal Schedule' and 'Agency Disposal Schedule' which categorized 'general function' and 'agency function' of an agency, according to DIRKS in Australia and ICA/IRMT. And for estimation of disposal date I had a thorough grasp of important records category presented in 'Constitution of General Assembly', interview to know the importance of tasks, and added examples of disposal schedule in western church archives. This study has significance that it was intended to embody 'the function-based classification' and 'disposal schedule' suitable for individual church, applying DIRKS in Australia and ICA/IRMT on absence of the theory or example which tried to present the function-based classification and disposal schedule for individual church. Also it is meaningful to present a model that can classify and disposal real records according to the function in individual church which has no recognition or way about records management.

• Journal of Cadastre & Land InformatiX
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• v.49 no.1
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• pp.123-144
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• 2019

The purpose of this study is to grasp factors the increasing population growth rate of the region through the regional and housing market characteristics. This paper has used multiple regression as the dependent variable (average of the population growth rate of 85cities during the last five years) and the independent variables analyzed the regional and housing market characteristics on the average. The results of the analysis, The regional and housing market variables that have had a significant impact on the regional population growth rate over the last five years are birth rate, employment rate, production available population growth rate, apartment rate, resale rights rate, and apartment turnover rate and the number of businesses per thousand and has decreased. In other words, The regions where the population increased by region for the last five years were the ones with the transfer of public institutions (innovation cities) and land development among the Seoul metropolitan area and non-Seoul metropolitan area excluding Seoul and metropolitan cities. The results of this study is intentional to suggest Policy point of view for the balanced regional development presented at the government level for other the metropolitan area, such as the small and medium cities that are undergoing population decline.

• Journal of Space Technology and Applications
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• v.1 no.1
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• pp.64-75
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• 2021

On the moon as well as the earth, one of the easiest ways to understand geological formation history of any region is to observe the stratigraphy if it is available, the order in which the strata build up. By analyzing stratigraphy, it is possible to infer what geological events have occurred in the past. Mare Nubium also has an unique normal fault called Rupes Recta that shows stratigraphy. However, a rover moving with wheels is incompetent to explore the cliff since the Rupes Recta has an inclination of 10° - 30°. Therefore, a quadruped walking robot must be employed for stable expedition. To exploration a fault with a four-legged walking robot, it is necessary to design an expedition route by taking account of whether the stratigraphy is well displayed, whether the slope of the terrain is moderate, and whether there are obstacles and rough texture in the terrain based on the remote sensing data from the previous lunar missions. For the payloads required for fault surface exploration we propose an optical camera to grasp the actual appearance, a spectrometer to analyze the composition, and a drill to obtain samples that are not exposed outward.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.11-17
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• 2022

Currently, the income and funds of the local economy are flowing out to the metropolitan area, and talented people, the driving force for regional development, also gather in the metropolitan area, and the local economy is facing a serious crisis. Local currency is issued by local governments and is a currency with auxiliary and complementary functions that can be used only within the area concerned. In order to revitalize the local economy, as local governments have focused their attention on the introduction of local currency, studies on the issuance and use of local currency are continuously being conducted. In this study, by using big data from data materials such as portals and SNS, the consumer image of local currency issued in local governments was identified through big data analysis, and based on the research results, the issuance and operation of local currency was conducted. The purpose is to present implications for The results of this study are as follows. First, by inducing local consumption through the policy issuance of local currency, it is showing the effect of increasing the economic income of the region. Second, local governments are exerting efforts to revitalize the economy and establish a virtuous cycle system for the local economy by issuing and distributing local currency. Third, the introduction of blockchain technology shows the stable operation of local currency. With academic significance, it was possible to grasp the changed appearance and effect of local currency through big data analysis and the policy direction of local currency.