• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2C
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• pp.109-116
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• 2006

Many application scenarios of ultra-wideband(UWB) radio assume non-line-of-sigit(non-LoS) signal propagations. Through-material propagation of UWB signal introduces a distortion of the waveform as well as attenuation, which will introduce a decrease of the correlation coefficient between the correlator template and the received signal. A hypothesis test approach to selection of the template waveform for UWB rake receivers is posed. Linde-Buzo-Gray(LBG) algorithm is used to select the candidate waveforms which are used to setup the hypothesis test. The performance of the algorithm is tested using a set of indoor non-LoS propagation measurement data.

• The Korean Journal of Applied Statistics
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• v.18 no.1
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• pp.15-26
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• 2005

This study compares the difference of academic achievements for college students who entered a school with different selection criteria, and it was based on the entrance data for Hankuk University of Foreign Studies during 2000-2003. The results of this research can be used as an evidence or a supporting material for the future entrance policies or strategies in other universities.

• Journal of the Korean Home Economics Association
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• v.38 no.3
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• pp.131-147
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• 2000

The purpose of this study was to identify food management behavior of housewives in island areas and to find if the behavior patterns were different between the regions, Hansan and Ullung island. An instalment based on previous researches was designed to measure food management behavior and was administered to 274 housewives in 1994 and 1998. Considering the condition of cooking-equipment possession, the percentage of possession for refrigerator, mix, electric range were significantly higher for households in Hansan Island than their counterparts. For food-budget planning, those in Ullung Island were more likly to plan their budget than those in Hansan Island. Menu planning patterns, considerable factors for food selection as well as cooking, and eating habits between meals were tuned out to be different between Hansan and Ullung areas. The findings of this study suggest that the condition of cooking-equipment possession, food-budget and menu planning, considerable factors for food selection and cooking, eating habits between meals were likely to vary depending on regions. Although housewives in two areas were living in island, they were not necessarily be uniform for all households but were diversified in food management behavior. Half of the respondents in Hansan Island and three-forth of the respondents in Ullung Island reported they had not planned their meal budget. The percentage of those who did not have their planned menu was 52.7∼54.1% in Hansan Island and 37.1∼38.5% in Ullung Island. When purchasing food material, housewives in Hansan Island consider the seasoning food as the most important factor, whereas those in Ullung Island consider family preference as the most important factor

• Transactions of Materials Processing
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• v.13 no.8
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• pp.689-695
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• 2004

This paper is concerned with the analysis of the forming load characteristics of a forward-backward can extrusion process. The analysis in this paper is extended to the selection of press frame capacity for producing efficiently final product at low cost. The possible extrusion processes to shape a forward-backward can part with different outer diameters are categorized to investigate quantitatively the forming load, forming energy and maximum pressure exerted on the die-material interface. The categorized processes are composed of combined and/or some basic extrusion processes. After the analysis of the forming load characteristics, the frame capacity of press suitable for a selected process could be determined along with securing the load capacity and with considering productivity. In addition, it is also suggested that different load capacities be selected for different dimensions of a part such as the wall thickness in forward direction. The work in this paper could be a good reference for analysis of complex extrusion and selection of proper frame capacity of press to achieve low production cost and thus high productivity.

• Journal of Distribution Science
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• v.15 no.6
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• pp.25-36
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• 2017

Purpose - The purpose of the study was to investigate the financial difficulty of the elderly in each income group and to examine the factors having related influence. The study adopted models with Korean welfare panel material and examined factors that having influence upon low income elderly's selection on retail business. Research design, data, and methodology - The study investigated the effects having influence upon the financial difficulty of elderly household as well as common household. It also examined independence variables having influence upon household's financial stress and found out the direction of financial control in elderly household. The study investigated the effect of financial stress upon economy to support consumption of the elderly. Results - In cases of financial difficulties, independent variables of the debt increased the financial difficulties of elderly households relying upon traditional markets. The elderly households had financial difficulties because of independent variables of the debt except for loan from financial institution. Conclusions - In this study, the elderly's financial stress had influence upon the use of retail business and the characteristics of residing and family. Further study shall give support policies for the elderly to alleviate financial burden.

• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.271-281
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• 2012

Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.10 no.2
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• pp.13-18
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• 2014

This paper proposes an optimum pipe material (PVC vs. PE) design & selection for open loop ground heat exchangers. Heat exchange efficiency and/or workability, and the need for trench insulation were investigated by comparing EWT (cooling mode) of each system. CFD simulations for the PVC and PE pipe with the same inner diameter show similar EWT. This is because the PVC pipe has a small thickness but a low thermal conductivity as compared to the PE pipe, and thus these two properties tend to offset each other. However, a hypothetically insulated pipe led to a meaningful drop of EWT. This means pipe insulation is of importance in performance of ground heat exchangers. From analyzing climate data and system operation, it is not advantageous to insulate trench pipes due to construction difficulties and ground temperature characteristics that are seasonally varied.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.6
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• pp.28-41
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• 1994

An efficient algorithm is proposed to select the proper tools and generate their paths for NC rough cutting of dies and molds with sculptured surfaces. Even though a milling process consists of roughing, semi-finishing, and finishing, most material is removed by a rough cutting process. Therfore it can be said that the rough cutting process occupy an important portion of the NC milling process, and accordingly, an efficient rough cutting method contributes to an efficient milling process. In order work, the following basic assumption is accepted for the efficient machining. That is, to machine a region bounded by a profile, larger tools should be used in the far inside and the region adjacent to relatively simple portion of the boundary while smaller tools are used in the regions adjacent to the relatively complex protion. Thus the tools are selected based on the complexity of the boundary profile adjacent to the region to be machined. An index called cutting path ratio is proposed in this work as a measure of the relative complexity of the profile with respect to a tool diameter. Once the tools are selected, their tool paths are calculated starting from the largest to the smallest tool.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.160-169
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• 2013

The materials used in the title sequence connotes a style & a content of film comprehensively. Therefore, the effect of emotional expression can be changed according to what materials are selected. Thus, the materials of which 42 title sequences are collected for the last 10 years are classified, and the category of materiality & material degree are defined with the semiotic rectangle. To investigate intensity of the material degree, the survey was done. As a result of the survey, the intensity was classified into 3 levels of material degree. The category of materiality used according to the genre of film was analyzed. As a result of the analysis, the materiality was selected according to the content regardless of genre, but there's any difference in the material degree. The intense material degree was used in a thriller and an SF mystery genre, and the medium one was used in the general genre, but, above all, drama and action genre. The weak one was used in a variety of genre, but specifically horror, SF mystery genre. It is significant that this study suggested the expression method in accordance with selection of materials in producing a title sequence to visualize film symbolically.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.3
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• pp.117-127
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• 2012

As increasing number of large-size earthquake around Korean peninsula, many interests have been focused to the earthquake strengthening of existing structures. Fiber reinforced plastic composite material is one of strengthening material widely used to increase seismic performance of structures. It should have high stiffness as well as large ductility to provide best strengthening result. Thus selection of stiffener and fiber in composite is of important. In this study, the optimal combination of fiber and stiffener is selected with variety of tensile tests. In order to investigate performance of chosen composite material, several finite element analyses are performed with proposed FRP composite material for existing RC columns. It is discussed that the seismic performance of strengthened columns through the load-displacement relationship. It is shown that the proposed composite material can increase the strength as well as ductility of exiting RC columns.