• Computers and Concrete
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• v.21 no.4
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• pp.471-484
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• 2018

Refined analysis depicting mass transportation and physicochemical reaction and reasonable computing load with acceptable DOFs are the two major challenges of numerical simulation for concrete durability. Mesoscopic numerical simulation for chloride diffusion considering binder, aggregate and interfacial transition zone is unable to be expended to the full structure due to huge number of DOFs. In this paper, a multiscale approach of combining both mesoscopic model including full-graded aggregate and equivalent macroscopic model was introduced. An equivalent conversion of chloride content at the Interfacial Transition Layer (ITL) connecting both models was considered. Feasibility and relative error were discussed by analytical deduction and numerical simulation. Case study clearly showed that larger analysis model in multiscale model expanded the diffusion space of chloride ion and decreased chloride content in front of rebar. Difference for single-scale simulation and multiscale approach was observed. Finally, this paper addressed some worth-noting conclusions about the chloride distribution and rebar corrosion regarding the configuration of rebar placement, rebar diameter, concrete cover and exposure period.

• Journal of Distribution Science
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• v.14 no.7
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• pp.53-61
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• 2016

Purpose - The production efficiency of agricultural crops has been the subject of numerous studies in the field of agricultural economics. This study examines the production efficiency of emerging vineyards in the 14 northern U.S. states and aims to understand raw input and managerial factors affecting the grape production with focusing on the effect of farm size. Research design, data, and methodology - Using a unique survey dataset that was collected from 176 vineyards in 2012, we employed data envelopment analysis (DEA) for estimation of production efficiency in individual vineyards. Production efficiency is regressed on various input and managerial covariates to understand factors influencing the productivity. Results - Although there exists positive correlation between the farm size and productivity of vineyards in Northern U.S. states, we find negative relationship when the farm size is instrumented by the additional farm size expansion indicator. The negative effect is more pronounced for the recently established vineyards. Conclusions - This study suggests that there needs to be adequate managerial improvements for emerging vineyards in northern states for the achievement of increased productivity.

• Asian Journal of Business Environment
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• v.10 no.4
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• pp.15-19
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• 2020

Purpose: This research aims to explore the level of air pollution in Jakarta, the epicenter of COVID-19 Pandemic in Indonesia and its surrounding provinces during the first month of the Pandemic. Research design, data and methodology: This study uses data, which have been obtained real time from API (Application Programming Interfaces) of air quality website. The measurements of Air Quality Index (AQI), temperature, humidity, and other factors from several cities and regencies in Indonesia were obtained eight times a day. The data collected have been analyzed using descriptive statistics and mapped using QGIS. Results: The finding of this study indicates that The Greater Jakarta Area experienced a decrease in pollutant levels, especially in the Bogor area. Nevertheless, some areas, such as the north Jakarta, have exhibited slow reduction. Furthermore, the regions with high COVID-19 confirmed cases have experienced a decline in AQI. Conclusions: The study concludes that the air quality of three provinces, Jakarta, Banten, and West Java, especially in cities located in the Jakarta Metropolitan Area during COVID-19 pandemic and large-scale social restrictions, is getting better. However, in some regions, the reduction of pollutant concentrations requires a longer time, as it was very high before the pandemic.

• The Research Journal of the Costume Culture
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• v.11 no.4
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• pp.541-550
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• 2003

This study is to research the costume of Korean envoys of the Chosun dynasty. The research results follow. The costume of three envoys including senior envoys and vice envoys is by, its different kinds, Gwandae, Jobok, Gongbok, and Pyongbok. According to the different purposes of occasions, these dresses were classified as the dress for ceremonies, the dress for banquets, and the dress for travel. For the ceremonial purpose, Gongbok and Jobok were mostly used. Gongbok was chosen when the envoys entered into the major cities or when they had ceremonies with the lord of the manor. The envoys wore Jobok for important ceremonies such as when receiving or presenting credentials or when entering into Chusima. For travel costume, Pyonbok of nobleman was used. The envoys wore Pyonbok during journey but they changed into Gongbok when they entered into the major cities such as Osaka or Kyoto in order to show their diplomatic etiquettes as representatives of the Chosun dynasty. And for the banquets, they wore Gongbok for official banquet and Pyongbok for private banquet. These findings of the different dress for different occasion indicate that there was a strict dress code according to the occasions and purposes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.3
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• pp.622-627
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• 2006

TSP(Traveling Salesman Problem) is a problem finding out the shortest distance out of many courses where given cities of the number of N, one starts a certain city and turns back to a starting city, visiting every city only once. As the number of cities having visited increases, the calculation rate increases geometrically. This problem makes TSP classified in NP-Hard Problem and genetic algorithm is used representatively. To obtain a better result in TSP, various operators have been developed and studied. This paper suggests new method of population initialization and of sequential transformation, and then proves the improvement of capability by comparing them with existing methods.

• Journal of the Korean Society of Costume
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• v.22
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• pp.45-60
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• 1994

Since 1988 the fur fashion industry in Korea has been difficult in exporting and competition with too many brands after opening the dom-estic fur market. However comparing with the interest of manufactures and consumers there are few of related references and books. So the purpose of this study is to put in order and summurize the manufacture in fur cloth-ing the informations of domestic and oversea fur markets and the other professional references. After all it is to help succeed in domestic and international fur markets and give the new ideas of designing and merchandising to the fur fashion industry. The results were as follows: 1. Contact with fur specialty stores in the international fashion cities and tourist cities directly. 2. Establish oversea factories in the low labor countries. 3. Exploit and invest in Russia china and the East European countries for suppliment of law materials and fur market. 4. Need the market research and promotion for encroachment in Japanese fur market. 5. Create the original brands with inter-national fashion sense. 6. Develop the manufacture line for diverse models in small lots matching with the modern life styles. 7. Need the fashion show exhibition pro-motion with reasonable prices and creative new designing with various color trimming texturizing and combination with the other materials. 8 Subdivide and distinguish labels into different types for avoiding with too much com-petition and comvenience of consumers. 9. Make an effort to weaken the black mar-ket the 30% of the domestic fur market.

• KIEAE Journal
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• v.13 no.2
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• pp.53-60
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• 2013

This study examined the building envelope structure used in small housings near urban area which have not good energy source in relation to the application of passive design for energy saving of small-sized architectural design firms in local cities and aimed to provide the basic materials of future design direction of designers and housing owners by analyzing economy of a project in order to know the amount of energy saving and additional expenses depending on the building envelope pattern. As a result of comparing and examining the energy saving cost from the period of use compared to investment by the thickness of insulating materials based on building envelope pattern for energy saving, it was found that the thicker the insulating materials are, the more energy saving amount is. While the current bead-type insulating materials have short payback period due to low initial investment, extruded insulating materials show the difference of five years compared to bead-type insulation because of its high initial investment.

• Atmosphere
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• v.19 no.4
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• pp.309-318
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• 2009

Vulnerability to heat was examined for populations of 6 major cities in South Korea (Seoul, Incheon, Daejeon, Gwangju, Daegu, and Busan). Daily excess mortality and maximum temperature from 1991 to 2005 were employed in this study. The results show that the standardized mortality increase associated with a $1^{\circ}C$ increase in daily maximum temperature above the city-specific threshold explains the heat acclimatization effect better than the threshold temperature itself. The estimated increase in mortality (standardized per 10 million population) associated with a $1^{\circ}C$ increase in temperature above the threshold is 4.8 in Incheon, 4.7 in Seoul, 4.3 in Daejeon, 2.8 in Gwangju, 2.4 in Daegu, and 1.5 in Busan, well reflecting the latitudinal locations and local climates of each city. Climate models project more frequent, more intense, and longer lasting heat waves in most land areas in both hemispheres in the 21st century under increasing greenhouse gas concentrations. In order to mitigate the adverse human health impacts due to excess heat, more detailed characteristics of acclimatization to heat need to be understood and quantified.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.2
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• pp.165-169
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• 2015

Green roofs are gaining much interest in many cities around the world due to its multi-purpose effects of water conservation, flood mitigation and aesthetic benefits. However it may cause additional water demand to maintain green plants, which may intensify the current and future water shortage problems. While ordinary concrete roofs and normal green roof drains off rain water, concave green roof system can retain rain water because of its water holding capability. In this study, the water conservation effect of concave green roof was compared to normal roof on #35 building in Seoul National University, Seoul, Korea. For seven rainfall events the amount of stored rainwater and runoff were measured and proved water conservation effect of the concave green roof system. The concave green roof system of which area is 140m2 showed effect of water conservation from 1.8ton to 7.2ton and the most influence factors on water conservation in green roof are rainfall and antecedent day. If this concave green roof is applied to many buildings in the cities, it is expected as a way to water conservation through rainfall storage.

• Land and Housing Review
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• v.2 no.2
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• pp.137-143
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• 2011

This study focused on urban regeneration projects to diversify projects methods. Since the enactment of legal redevelopment projects, they were concentrated on improving the physical environment and supplying housings. In this article, 12 cities' urban regeneration policies and projects will be examined to point out the characteristics of each regions via documentary studies and interview investigations. They could be divided into 3 groups by population and region. Finally, this article is intended to propose diversified regeneration methods depending on the regions and to address implications on the regeneration policies.