• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.81-88
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• 2018

The present study evaluated the effective arrangement approach of transverse reinforcement in the jacket section for seismic strengthening of reinforced concrete columns. To simulate the full-scale columns, the section dimensions were determined as $450{\times}450mm$ for non-seismic existing columns and $750{\times}750mm$ for section enlargement strengthening columns. Over-lapped channel-shape bars and prefabricated bar units were proposed for closed-hoops in the jacket section, and conventional cross-ties anchored into existing columns and V-ties were considered for the supplementary ties. Test results showed that the axial capacity of the existing column and section enlargement columns with over-lapped channel-shape hoops was similar to the nominal strength calculated using ACI 318-14 procedure whereas the section enlargement column with prefabricated bar units possessed 1.25 times higher axial capacity than the nominal prediction. Furthermore, the axial ductility ratio of the section enlargement column with prefabricated bar unit was 139% higher than that of the existing column despite the potential size effect on ductility of concrete. Thus, it can be concluded that the developed prefabricated bar unit technique is practically useful for preventing the premature buckling of longitudinal reinforcement and confining core concrete in the section enlargement strengthening columns.

• Journal of Korean society of Dental Hygiene
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• v.18 no.4
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• pp.477-488
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• 2018

Objectives: The purpose of this study was to investigate career competency, tasks, and job satisfaction of public servants, public institutions, and researchers. Methods: The survey was conducted about career competency, job satisfaction, and satisfaction on work life. Next, they interviewed on the characteristics of each job by two or three dimensions. The following conclusions were obtained from July to August 2017. Results: Career competencies were GPA with 3.87, 818 points of TOEIC score, and ITQ certification. Public servants required the information on literacy skills for employment and job performance, while civil servants need more than one year of clinical experience in the dental hospital. The non-commissioned officer needed a written test and fitness training. The health insurance review and assessment center required more than one year of experience from general hospital or medical institutions. Researchers required a research career, language skill, and professors required research and teaching experiences with clinical experience more than three years. The main job tasks were as follows; for public servants, they were official document processing and community projects. For the civilian workers and military/noncommissioned officers, they were medical assistant and administrative works. The employees of the health insurance review and assessment service are examining the medical expenses and the medical examination, the researchers are experimenting, researching and writing articles, and the teaching staff are lecturing and conducting individual research. Conclusions: The results of job satisfaction survey showed that occupational satisfaction was the highest in civil servants, researchers, and teaching professions. Job security was the highest in health workers and health inspectors' evaluation centers, and time vacancy was the highest in civilian workers and military/noncommissioned officers. If you want to work in such an institution, you should prepare elements that match your basic literacy and job specific characteristics. And we should try to increase the satisfaction of work even after work.

• Journal of the Society of Disaster Information
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• v.15 no.4
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• pp.524-530
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• 2019

Purpose: In this paper, we construct a detailed three-dimensional interface element using a three-dimensional analysis program, and evaluate the composite behavior stability of the connector by applying physical properties such as the characteristics of general members and those of reinforced members Method: The analytical model uses solid elements, including non-linear material behavior, to complete the modeling of beam structures, circular flanges, bolting systems, etc. to the same dimensions as the design drawing, with each member assembled into one composite behavior linkage. In order to more effectively control the uniformity and mesh generation of other element type contact surfaces, the partitioning was performed. Modeled with 50 carbon steel materials. Results: It shows the displacement, deformation, and stress state of each load stage by the contact adjoining part, load loading part, fixed end part, and vulnerable anticipated part by member, and after displacement, deformation, The effect of the stress distribution was verified and the validity of the design was verified. Conclusion: Therefore, if the design support of the micro pile is determined based on this result, it is possible to identify the Vulnerable Parts of the composite behavior connector and the degree of reinforcement.

• (The)Study of the Eastern Classic
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• no.63
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• pp.83-113
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• 2016

This paper is focused on objective and meaning of its compilation through reviewing system, composition, method of description, and content of "Jwagyebudam". "Jwagyebudam" has all round form of a history and character book by recording via arranging figures from the end of 16th century to the middle of 18th century in a chronological order. Figure were not only assigned at close range by steretyping people into groups to a degree in it, but also recorded in a chronological order. In view of method of description, "Jwagyebudam" concentrated a theme by recording via separating different people associated from a figure and content of the same event by using the same method like 'Hogeonbeom(互見法)' shown in "Sagiyeoljeon(史記列傳)". In addition, it obtained effect to objectify evaluation of figures included. In a method of embodying figures, it has described concretely and in a three dimensions figures by recording anecdotes and poems associated with them via focusing on lifelong characteristic aspect of corresponding figures. In other words, "Jwagyebudam" can be called by biographies or character books, writings specialized in characters center among writings of method to weave freely experience. In a broad sense, it can be called a writing to cover a function of history book, poem and picture. This was located to a starting point of variation of inclusive and descriptive method. Namely, several kinds of writings in late Joseon dynasty can show aspect to fulfill specialized aspect gradually.

• Journal of Broadcast Engineering
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• v.24 no.5
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• pp.879-891
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• 2019

This paper provides performance evaluations of various channel estimation schemes for Advanced Television Systems Committee (ATSC) 3.0 multiple-input multiple-output (MIMO) system under a fixed reception environment. ATSC 3.0 MIMO system can obtain high spectral efficiency and improved reception performance compared to conventional terrestrial broadcasting systems. The ATSC 3.0 MIMO defines Walsh-Hadamard and null pilot encoding algorithms and the amplitude and phase of MIMO pilots are different from those of single-input single-output pilots. At the receiver, linear and discrete Fourier transform (DFT)-based interpolations can be used for the channel estimation. This paper provides the various combinations of the interpolation schemes for channel estimation in time and frequency dimensions, and then analyzes the performance of the various combinations through the computer simulation. The results of computer simulation show that the combination of the linear interpolation in the time dimension and then DFT-based interpolation in the frequency dimension can obtain the best performance among the considered combinations.

• Journal of vocational education research
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• v.30 no.4
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• pp.69-87
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• 2011

Until now, most of the attention related information and knowledge transmission is on the verbal message provided by educators. But recently, many researchers are emphasizing importance of nonverbal communication behavior in the evaluation of communicator include educators. When nonverbal messages reinforce verbal messages, meaning is conveyed quickly and easily and with increased comprehension. The purpose of this study is to analyze the effect of professor nonverbal communication on students' academic achievement. In this study, nonverbal communication was divided into the three dimensions of kinesis, proxemics, paralanguage, and physical appearance. It was studied to examine the direct or indirect effects of nonverbal communication on attitude toward the professor and academic achievement. Additionally, it examined the moderating effect of academic self-efficacy in the relationship between attitude toward the professor and academic achievement. The data were collected from 214 college students using an online survey. The results showed that the kinesis, proxemics, and physical appearance, except paralanguage, have significantly positive influence on attitude toward the professor. And the moderating effect of academic self-efficacy has also been founded.

• Journal of the Korean Chemical Society
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• v.64 no.6
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• pp.327-333
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• 2020

Performance of a portable GC that can be utilized for the real time determination of volatile organic compounds in air was evaluated. It employs purified/compressed ambient air as the carrier gas eliminating the need for high pressure gas tanks. The compact system with dimensions of 35 × 26 × 15 ㎤ and weight of 5 kg is powered by either a 24 V DC external adapter or battery pack. Chromatograms of the mixture sample including benzene, toluene, ethylbenzene, and oxylene at concentrations of 1 ppmv and 20 ppmv represent a good reproducibility: 3.79% and 0.48% relative standard deviations (RSDs) for peak area variations; 0.40% and 0.08% RSDs for retention times. The method detection limit was 0.09 ppmv. A 30 m long, 0.28 mm I.D. column operated at an optimal condition yielded a peak capacity of 61 with good resolution for a 10 min isothermal analysis. The relative standard deviations (RSD) of the peak area variations and retention times during consecutive measurements over 27 h were less than 2.4%RSD and 0.5%RSD, respectively. Thus, this instrument makes it suitable for continuous and field analysis of low-concentration VOC mixtures in the indoor/outdoor environment as well as the spillage accident of hazardous chemicals.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.637-648
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• 2021

In order to support the establishment of a farming plan, it is important to preemptively evaluate crop changes and to provide precise information. Therefore, it is necessary to provide customized information suitable for decision-making by farming stage through scientific and continuous monitoring using drones. This study was carried out to support the establishment of the farming plan for ground vegetable. The cultivation management map of each information was obtained from preliminary study. Three cultivation management maps include 'field emergence map', 'stress map' and 'productivity map' reflected spatial variation in the plantation by providing information in units of plants based on 3-dimensions. Application fields of the cultivation management map can be summarized as follows: detect miss-planted, replanting decision, fertilization, weeding, pest control, irrigation schedule, market quality evaluation, harvest schedule, etc.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.3
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• pp.183-198
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• 2021

The EPB (Earth Pressure Balanced) shield TBM method restrains the ground deformation through continuous excavation and support. Still, the significant surface settlement occurs due to the ground conditions, tunnel dimensions, and construction conditions. Therefore, it is necessary to clarify the settlement behavior with its influence factors and evaluate the possible settlement during construction. In this study, the analytical model of surface settlement based on the influence factors and their mechanisms were proposed. Then, the parametric study for controllable factors during excavation was conducted by numerical method. Through the numerical analysis, the settlement behavior according to the construction conditions was quantitatively derived. Then, the qualitative trend according to the ground conditions was visualized by coupling the numerical results with the analytical model of settlement. Based on the results of this study, it is expected to contribute to the derivation of the settlement prediction algorithm for EPB shield TBM excavation.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.258-269
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• 2021

The purpose of this study is to establish a system to evaluate the ecological soundness of the Geum river basin. The study target area is 14 sub-watersheds of the Geum river basin. For the selection of indicators to ensure transparency and consistency of the evaluation indicators, the ecological soundness indicators were secured by using the indicator adjustment method derived in consideration of the intrinsic weight change characteristics between indicators. The index with the greatest impact on the final composite index was identified as the index of the aquatic ecology among the water quantity, water quality, aquatic ecology, and habitat-riparian environment dimensions. As a result of analyzing the ecological health index of the river, the watershed upstream of the dam (based on the Daecheong -dam) was evaluated to be in relatively good condition until 2014 compared to the base year(2008), and the watershed downstream of the dam was evaluated to be in a poor condition. The annual trend of changes in the ecological soundness index on an annual basis is as follows. In the case of Yongdamdam, Yongdamdamdownstream, Bocheong-chun, Daechungdam, Daechungdamdownstream, and Nonsancheon, although there are differences by time period, the soundness index is in declining. On the other hand, Mujunamdaecheon, Yeongdongcheon, and Gapcheon were evaluated to have improved soundness, while Chogang, Daechungdamupstream, Mihocheon, Gongjugeumgang, and Geumgangestuary were evaluated to deteriorate again after soundness was improved.