• Journal of Korean Society of Water and Wastewater
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• v.21 no.6
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• pp.727-735
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• 2007

The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1128-1134
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• 2014

In this paper, the effects of a metamaterial slab with negative permeability in a magnetically coupled wireless power transfer system (WPT) in the overall performance are analyzed quantitatively in terms of the effective quality factors of the loop resonators and coupling coefficient considering the slab losses, based on an equivalent circuit. Using the ideal metamaterial slab(lossless slab), the WPT efficiency is improved considerably by the magnetic flux focusing. However, the practical lossy slab made of RRs or SRRs limits the significant enhancement of WPT efficiency due to the relatively high losses in the slab consisting of RRs or SRRs near the resonant frequency. For the practical loop resonator, other than a point magnetic charge, using the practical lossy metamaterial slab in order to improve the transfer efficiency, the width of the slab needs to be optimized somewhat less than the half of the distance between two loop resonators. For the low-loss slab with its loss tangent of 0.001, the WPT efficiency is maximized at 93 % when the ratio of the slab width and the distance between the two resonators is approximately 0.35, compared with 53 % for the case without the slab. The efficiency in case of employing the high-low slab(loss tangent: 0.2) is maximized at 61 % when the slab ratio is 0.25.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.10 no.1
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• pp.5-14
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• 2003

Recently, there has been an increasing need for long-term care and comprehensive health care services in community settings. The Ministry of Health and Welfare introduced the Hospital-Based Home Nursing Care Program in 2000. Before this initiative, there was a Home Nursing Demonstration Center, affiliated with the Seoul Nurse Association, had offered home nursing services with the financial support from the local government. since 1993, the Center's nursing staff has been engaged in a general hospital in an effort to provide home nursing care services within Korea's health care system. The purpose of this study was to analyze and identify characteristics of community-based home nursing care supplied by a community-based home nursing team engaged in a general hospital. Also. visit nursing care services provided by public health centers were evaluated in terms of accessibility and supply versus demand, to enhance the accessibility of low-income patients living in Seoul to home nursing care services. Data were collected from home nursing insurance reimbursement claims submitted by the community-based home nursing care team from March 1 to October 30 in 2001 and a questionnaire survey on home-visit nursing services of 25 public health centers in Seoul. The subjects consisted of 197 patients and 12 public health centers. The result were as follows. First, medical institution's community-based home nursing care program was better in technical quality than health-center-based home-visit nursing care. In addition. the pattern of the subject patients was similar to that of hospital-based home nursing care program. Second, there was a high demand for community-based home nursing care while only a small number of home-visiting nurses served at public health centers in Seoul. As a result, many patients could not receive adequate care. Finally, we suggest that community-based home nursing care program should be introduced in the national health system to meet the at-home care needs of severely ill low-income patients. Furthermore, to better utilize home nursing and visit-nursing care resources and offer continued care for patients in community settings, an efficient referral network should be built among related institutions. This would require improvement of reimbursement system and amendment of the law related to health insurance system and community-based home nursing care services.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.255-265
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• 1996

The purpose of the present study is to evaluate dimensional consistency, bristle finishes and bristle rebound rate of four brands of $Dentichek^{(R)}$ toothbrushes(regular-male, regular-female, soft-male, soft-female) to provide referneces in product enhancement and quality control for the manufacturer and to provide suggestions in selecting appropriate toothbrushes for general public. The results are as follows : 1. The size of the head is : $25.10{\times}8.10mm$ for male toothbrushes and $19.90{\times}8.10mm$ for male toothbrushes, while the size of the bristle portion is: $29.90{\times}10.65mm$ for male toothbrushes and $25.25{\times}10.65mm$ for female toothbrushes. 2. The length of the bristles is 10.70mm in all four groups. 3. The length of the toothbrush is 192mm in all four groups. 4. The number of tuft is 43 for male toothbrushes and 35 for female toothbrushes. Tuft arrangement is 4-row configuration in all four groups. 5. The number of bristles in a tuft ranges from 40-56, with higher numbers in male toothbrushes compared to the female counterparts, and higher numbers in the "soft" variety compared to the regular ones. 6. The diameter of the bristle is : 0.21mm for the outer row and 0.19mm for the inner row in the regular brand, and 0.17mm for the soft brand. 7. Irregularly finished bristle ends comprised 20-22% of the total bristles. 8. The bristle rebound rate ranges from 55.9% to 62.3%, with higher numbers in the "soft" variety compared to the regular ones. The above results show that $Dentichek^{(R)}$ toothbrushes meet the requirements of Korean Dental Association standards for toothbrushes, but further evaluations of their effects on periodontium and plaque elimination in actual in-use situation may be needed.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.567-586
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• 2011

The purpose of this study was to investigate the gifted students' view on argumentation and the aspects of the argumentation in problem-solving type experiment. As a result, very lively argumentation was identified but quality enhancement on argumentation wasn't found over time. Students made frequent use of dialogic argumentation component, and especially, request & response component was highly used. Though usage frequency is low, the component of ground & question on ground was shown in 3rd class, and simple agreement gradually reduced, and reinforcing elaboration & metacognitive question has slightly increased. Also, students' argumentation were closely related to teachers' teaching approaches as some teacher-led steps doesn't appear in students' argumentation. By comparison in steps, 'problem solving activity & result analysis' step included 2 times more argument components than the previous step. We also found that method grouping teams does not almost affect the argumentation of gifted students. By survey results, most students recognized that they experienced free argumentation and this program activate argumentation and 'strange things' or 'difficulty' of program topics are obstacles in vitalization of argumentation. 'Surface growth experiments' was the most lively argumentation topic. The argumentation was lively made in the step of 'finding solution. 'Teachers' scaffolding accelerate the argumentation and help resolve difficulties in argumentation. Thus, students have positive recognition for the argumentation process in the experiments and recognize that argumentation process is needed.

• Progress in Medical Physics
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• v.16 no.4
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• pp.192-201
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• 2005

Experiments and simulation were done to study the impact of contrast agent when CT scan was used to attenuation correction for PET Images in PET/CT system. Whole body phantom was imaged with various concentration of iodine-based contrast agent using CT. Mathematical emission and transmission density map with liver were made to simulate for whole body FDG Imaging. A variety of factors were estimated, including non-uniform enhancement of contrast agent, concentration and distribution size of contrast agent, noise level, image resolution, reconstruction algorithm, hypo-attenuation of contrast agent, and different time phases for contrast agent. Experimental studies showed that Hounsfield unit depends on the concentration of contrast agent and tube voltage. From the simulation data, contrast agents Introduced artifacts and degraded image quality on the attenuation-corrected PET images. The severity of these effects depends on a variety of factors, including the concentration and distribution size of contrast agent, the noise levels, and the Image resolution. These results Indicated that the impact of contrast agents should be considered with a full understanding of their potential problems in clinical PET/CT images.

• Journal of Practical Engineering Education
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• v.12 no.1
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• pp.163-176
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• 2020

Promoting job growth and quality has been central to developing countries to reduce poverty for decades. In this regard, Nepal is not unique in its need to develop effective TVET programme as it is considered showing positive association with workforce development and productivity. While the copious academic literature has highlighted upon staff training programme in general education, it encounters lack of adequate attention in the field of TVET education. The purpose of the study is to identity and prioritise the professional development needs for the teachers of TVET sector in Nepal. A sample(N=317) of Nepalese teachers from seven provinces were asked to answer the scale. The Borich needs assessment model was employed to assess the perceived level of importance and present preferred training modules among 29 teaching subjects. Moreover, a quadrant analysis using 2×2 matrix was used as a diagnostic tool to denote overriding training topics. The result shows that following competence skills constructs were perceived to be in high need of enhancement as well as in existence of discrepancies: 'occupational characteristics of TVET trainer', 'training needs analysis and curriculum development', 'curriculum development based on national competence standard(NCS)', and 'Institution management evaluation'.

• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.45-54
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• 2010

Recently more and more construction projects have become high-rise, complex and intelligent. Accordingly, such projects require an integrated management system for tasks, with a lean approach to construction with work processes for management and productivity. In particular, Construction Information Technology (CIT) fields are concerned with Building Information Modeling (BIM), which represents the process of generating and managing building data during its life cycle. Constructability research has progressed for the project goal which is a cost-time-quality of optimization by integrated construction knowledge and experience. However, the current constructability process has not been performed efficiently, as the existing 2D drawings and papers lack consistent and accurate information, it is difficult to share the contents of work, and the use of information is inefficient. This study proposes that the reformation and enhancement of BIM-based constructability work process can lead to brilliant performance in the framework of the construction phase through achieving collaboration between the design team and the workers at the site.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.83-91
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• 2016

In the past, the domestic construction industry mainly comprised quantitative investment through the supply of labor force, however, there have recently been opinions that there is a need for qualitative investment in the workers in order to obtain competitiveness in construction markets. Accordingly, there are much re-education courses for workers in the construction industry, but there is much negative awareness as to the efficiency of the current re-education course due to many problems. This study aimed to examine the problems o f currently executed re-education courses and proposed an improvement plan for the qualitative enhancement of domestic construction re-education. Thus, a multiple regression analysis was conducted to deduce two core problems an improvement plan. The improvement plan for the problems comprised the NCS/CDP-based integrative education program through an AHP. The contribution of this paper will result in the execution of a more effective construction industry re-education program, and the result of such program to achieve qualitative growth in the workers in the construction industry

• Journal of Technology Innovation
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• v.26 no.1
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• pp.85-105
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• 2018

This study analyzes the economic impacts of Korean R&D expenditure on the industrial structure by technological levels using 2010~2014 Input-Output table data. The industrial structure is reclassified into 4 manufacturing industries by OECD's Technology Intensity Definition. Then, we analyzes the production-inducing and value added-inducing of those industries. As the results of the analysis, it is found that the production-inducing effect by the R&D expenditure has been higher in the middle-high and middle-low technology manufacturing and that the value added-inducing effect has been higher in the middle-high technology manufacturing. On the other hand, the production and value added-inducing effects has been lower in the high-tech manufacturing which is highest in the R&D expenditure. The above results indicate that industrial structure has not been linked with the quality ladder that expresses the enhancement of tech level through R&D expenditure. Based on these results, the policy recommendation implies that R&D expenditure should be concentrated to improve the production- and value-added effects of the high technology manufacturing in order to advance the industrial structure. However, this study has the limitation that the analyses on the dynamic-inducing effects are not carried out due to the lack of fixed capital formation data.