• Journal of KIBIM
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• v.1 no.2
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• pp.24-29
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• 2011

BIM technology, based on 3D model of civil engineering structures, creates and manages information of the structures throughout four stages: Planning, design, construction, and maintenance. BIM is now used around the globe for improvement of the construction productivity. However, in order to expect the efficient engineering work, collaboration system between participants in a construction project is necessary. Therefore, in this paper BIM based CPLM (Construction project lifecycle management) system was designed and developed by analyzing the requirements of participants of a construction project. CPLM system offers an environment which enables the sharing and management of information according to the each stage of construction. CPLM is expected to aid cooperative decision-making during the overall construction process through the process innovation and the efficient data management.

• Journal of computational fluids engineering
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• v.20 no.3
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• pp.8-14
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• 2015

More and more, spaces are decreasing which satisfy multiple requirements for wind power plants. However, areas which have excellent wind resources and are free to civil complaints occupy a large space, although they are exposed to the cryogenic environment. This study conducted a thermal-fluid analysis of a cryogenic chamber for testing large wind turbine parts exposed to the cryogenic environment. The position of supply air is placed to the upper area to compare each cooling performance for each location of various outlets in mixing ventilated conditions. The study carried out CFD analysis for the chamber both with and without a test object. For the cases without the test object, the air temperature of the upper supply and down extract type chamber was cooled faster by 5-100% than the others. However, for the cases with the test object, the object temperature of upper supply and center extract on the opposite side type chamber was cooled faster by 33-132% than the others. The cooling performance by the air inside the chamber and the test object did not show the same pattern, which implicates the need to consider the cooling performance by not only the air but also the test object in the large cryogenic chamber design for testing large parts.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.3
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• pp.377-385
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• 2018

Super-speed vacuum tube system, where the air resistance is minimized to obtain high speed of the vehicle, is considered to be a viable alternative transportation system. Air-tightness is one of the most important design requirements of the system, because the internal pressure of the system needs to be maintained significantly lower than the atmospheric pressure. This study performed an experimental test, where a series of concrete tube specimens were applied by external loads to induce cracks and the effective air-permeability of the cracked tube structures were measured. The test results indicates that the information on the length and the width of the load-induced cracks are not enough to anticipate the system air-tightness, whereas the load-induced displacement has higher correlation with the systems air-tightness. Based on these results, a direction of future research for effect of the load-induced cracks on the system air-tightness is suggested.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.3
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• pp.303-309
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• 2015

In this study, a vehicle dynamic analysis and roller rig test were performed to evaluate the applicability of a suspensionless composite bogie to railway vehicles. A vehicle dynamic analysis was carried out under different rubber bushing stiffness values. The stiffness of the rubber bushing that plays a role in guiding wheel sets was varied in the range of 10-100 MN/m, in 10-MN/m steps. Based on the results, the composite bogie with a rubber bushing stiffness of more than 40 MN/m satisfied the design requirements. In addition, a rubber bushing with a stiffness of 81 MN/m was fabricated, and a roller rig test was performed. Based on the test results, the vehicle equipped with the composite bogie had a critical speed of 363 km/h, which agreed with the simulation result within an error of 10%.

• Journal of the Korea Furniture Society
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• v.28 no.4
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• pp.340-354
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• 2017

Currently, the global furniture market can not overlook environmental problems due to changes in environmental regulations. In order to grow into a global corporation, environmentally friendly design became essential. In addition, domestic and foreign consumers are increasingly interested in and spending on children's furniture, and demand for environment - friendly furniture for children's health and emotional development is increasing. In the era of universal consumer tastes due to massive mass production, it has been changed into a multi-product small-volume production period that reflects the preferences of various consumers, so that various types of furniture that meet individual preferences are required. Therefore, in this study, we investigated various personal opinions, perception, preference, propensity to use furniture, purchasing points, etc. for environmentally friendly children's furniture, and provided basic data for environmentally friendly children's furniture development that reflects consumer preference and requirements. Accordingly, 243 parents who have more than one child living in Seoul, Gyeonggi, and Incheon were surveyed about the use of children's furniture and the perception and preference of environmentally friendly children's furniture. According to the survey results, 64.57% of the respondents knew about eco - friendly children's furniture and the most popular way to get to know eco-friendly furniture was Internet advertising (49.48%). The rate of recognizing eco-friendly furniture as healthy furniture with no emission of hazardous substances was high as 56.16%. The purchase intention of eco-friendly children's furniture was very high at 86.01% and the most important factor in purchasing was the harmlessness to the human body (56.88%). 59.50% said that it is not possible to distinguish environmentally friendly furniture, which means that there is not much information to consumers yet. In addition, the preferred price range is 500~1000 thousand won, and the preference for the rest furniture is high. In the preferred form type, unit type modular furniture is 36.13%, in the material, wood is 72.35%, in the color, the color of wood with wood grain is high as 45.56%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.2
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• pp.216-233
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• 2013

Conventional optimization designs of wireless networks mainly focus on spectral efficiency (SE) as a performance metric. However, as diverse media services are emerging, a green wireless network, which not only meets the quality of experience (QoE) requirements for users and also improves energy efficiency (EE), is the most appropriate solution. In this paper, we firstly propose the unit QoE per Watt, which is termed QoE efficiency (QEE), as a user-oriented metric to evaluate EE for wireless networks. We then analyze which is the kind of wireless resource given priority to use under different scenarios to obtain an acceptable QEE. Particularly, power, delay and data-rate related to QoE are separately addressed for several typical services, such as file download, video stream and web browsing services. Next, the fundamental tradeoffs are investigated between QEE and SE for wireless networks. Our analytical results are helpful for network design and optimization to strike a good balance between the users perceived QoE and energy consumption.

• Journal of Animal Science and Technology
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• v.59 no.7
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• pp.13.1-13.6
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• 2017

This study was conducted to investigate the behavioral and physiological changes of heat stressed Corriedale ewes exposed to water deprivation. Nine Corriedale ewes (average $BW=45{\pm}3.7kg$) were individually fed diets based on maintenance requirements in metabolic crates. Ewes were assigned into three groups (9 sheep per treatment) according to a $3{\times}3$ Latin square design for 3 periods with 21-d duration for each period. The control (CON) group was given free access to water, 2 h water deprivation (2hWD), and 3 h water deprivation (3hWD) following feeding. No differences were found in fecal excretion frequency, standing frequency (number/d), and sitting frequency among the groups (p > 0.05). Measurements of standing duration (min/d) and urine excretion frequency (number/d) showed a significant decrease whereas sitting duration (min/d) showed a significant increase in the 2hWD and 3hWD groups when compared with the CON group (p < 0.05). Fecal score and heart rate (number/min) were not different among the groups (p > 0.05). However, respiratory rate (number/min) and panting score were found to be significantly higher in the 2hWD and 3hWD groups than in the CON group (p < 0.05). It is concluded that water deprivation following feeding intensifies physiological heat stress related indicators such as respiratory rate and panting score and changes behavioral parameters such as water intake and urine excretion frequency in heat stressed ewes. Daily adaptation to the extreme environmental conditions may occur actively in ewes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.12
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• pp.1201-1206
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• 2008

This study is focused on the investigation of the modal characteristics of the preliminary models of science technology satellite-3 (STSAT-3). Prior to the final decision of the composite structure model, several candidate structure models have been developed so as to find the most qualified structures with respect to the satellite structure systems' requirements and then utilize the information achieved to a real design. The main structure is composed of fiber reinforced composite faced honeycomb sandwich panel whose modal characteristics are found and compared to each other by means of finite element numerical analyses. Results from the current study demonstrate that a rectangular box shape having supporting inner panel shows relatively higher fundamental mode frequencies than octagonal box shape and etc., and regardless of the structure model shape tested herein, the fundamental mode turns out lateral bending mode.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.4
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• pp.25-40
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• 2012

This paper suggests the way to build the integration of internal server by using link server with virtualization method. With the development of on-line games, game communities began to be formed by users, players get fun from playing games, sharing online space with friends, clans, and parties. However, the limit of physical server restrict the allows under average a hundred users to play at same time and place, and three thousand to ten thousand people to access to game community with chat, message, friends functions. By following the explanation of the method from this paper, this limit can be overcome. It will give the function to share information of all connected users in one displayed server. This paper demonstrates the key quality requirements of the server built by this way such as scalable architecture, consistency, and latency is fulfilled.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.3 s.39
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• pp.251-262
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• 1991

The roles of fashion merchandisers (merchandise managers) in women's apparel industry and their perceptions of the job requirements as a fashion merchandiser were investigated to understand present fashion merchandising activities in the industry and suggest desirable roles of fashion merchandiser for further development of the industry. The research questionnaires were administered to fashion merchandisers working in the ten national brand women's apparel firms. The results of the study were as follows . 1. Annual sales volumes of most surveyed firms were more than five billions won and eight out of ten surveyed firms have fashion merchandisers in their firms. 2. Fashion merchandisers worked at a specific brand merchandising division sales and operations division or merchandise planning division. A fashion merchandiser generally supervised one brand. 3. Fashion merchandiser's work experience ranged from four to fifteen years showing a great deal of experience in the apparel industry. Their majors at university were mostly business and few majored in clothing and textiles, or textiles. 4. In general, the role of fashion merchandiser was a management specialist who was responsible for identifying target markets analyzing fashion trends, planning of the merchandise development budget planning, manufacturing planning, selling, advertising and sales promotion and distributing the merchandise. At some firms fashion merchandi-sers were not responsible for advertising, display, and receiving the orders. 5. Surveyed fashion merchandisers perceived the desirable fashion merchandiser's role as a management specialist conducting overall business activities in the areas of merchandise planning, manufacturing, selling and distribution. They also mentioned the following personal characteristics such as vision leadership, and persuasion as desirable characteri-stics for those who aspire to a career in fashion merchandising. 6. Surveyed fashion merchandisers emphasized relevant and realistic experiences in fashion merchandising education. Several ways were suggested to help the educator keep in touch with business and bring reality to students. They are . field work, bringing professionals into the classroom to speak to the students, emphasizing clothing and textiles education including merchandising area, and establishing a Department of Fashion Merchandising.