• Journal of Korean Society of Water and Wastewater
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• v.23 no.1
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• pp.57-67
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• 2009

Under the supply-oriented policy, efficiency and rationale have not been fully considered in planning of water supply facilities in Korea. As a case, this study shows that large-size systems are suffering from overcapacity problem of water treatment plants, and thus discusses what options should be applied to deal with inefficiency. Water demand of large-size systems has suddenly decreased for the last 10 years while water demand has been often assumed to increase at a regular rate in planning of plants according to excess capacity hypothesis. This inconsistency led to a serious overcapacity. In 2006, total excess capacity of nine large-size systems was more than 1.2 times as large as maximum daily demand of total customers in Seoul. However, their options are expected to stay ex post facto. To prepare the risk of overcapacity, and draw large benefits out of the plants, the authors and other professionals in Korea should further discuss the more adaptive method for prediction of water demand, and systems integration between a large-size system and adjoining systems.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.501-502
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• 2009

This paper presents a strengthening technique of weakened telegraph pole using an inflating agent to adjust chemical pre-stressing. The strengthening technique increases only resisting capacity and ductility of telegraph but also limited quantity and application ability of FRP. The chemical pre-stressing and the resisting capacity are investigated experimentally. From the results, it is confirmed that it is possible to control the degree of applied pre-stressing by controlling the amount of inflating agent. In addition, the pre-stressing can increase resisting capacity up to three times compared with no pre-stressing.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.249-254
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• 2008

Ag doping effect on $Li[Ni_{0.2}Li_{0.2}Mn_{0.6}]O_2$ cathode material was studied. Specially, we focused on rate performance of Ag doped samples. The $Li[Ni_{0.2}Li_{0.2}Mn_{0.6}]O_2$ powder was prepared by simple combustion method and the Ag was doped using $AgNO_3$ during gelation process. Based on X-ray diffraction analysis, there was no structural change by Ag doping, but the 'metallic' form of Ag was included in the doped powder. Both bare and Ag 1 wt.% doped sample showed similar discharge capacity of 242 mAh/g at 0.2C rate. However, as the increase of charge-discharge rate to 3C, Ag 1 wt.% doped sample showed higher discharge capacity (172 mAh/g) and better cyclic performance than those of bare sample. The discharge capacity of Ag 5 wt.% doped sample was relatively low at all rate condition. However it displayed better rate performance than other samples.

• Steel and Composite Structures
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• v.23 no.2
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• pp.161-172
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• 2017

A new composite tube connection method called the pre-tightened teeth connection technique is proposed to improve the composite tube connection efficiency. This paper first introduces the manufacturing process of the proposed technique. It then outlines how the mechanical properties of this technology were tested using four test groups. The factors that influence the load-bearing capacity and damage model of the connection were analyzed, and finally, the transfer load mechanism was investigated. The following conclusions can be obtained from the research results. (1) The new technique improves the compressive connection efficiency by a maximum of 79%, with the efficiency exceeding that of adhesive connections of the same thickness. (2) Changing the depth of teeth results in two types of damage: local compressive damage and shear damage. The bearing capacity can be improved by increasing the depth, length, and number of teeth as well as the pre-tightening force. (3) The capacity of the technique to transfer high loads is a result of both the relatively high interlaminar shear strength of the pultruded composite and the interlaminar shear strength increase provided by the pre-tightening force. The proposed technique shows favorable mechanical properties, and therefore, it can be extensively applied in the engineering field.

• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.445-455
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• 2000

This study proposed to beam-column joint model consisting of different type structural member to develop new structural system in the structural viewpoint as to a method to overcome various problem according to change of construction environment. This study promoted rigidity and capacity to stiffen reinforced concrete for steel structure end to increase rigidity of long spaned steel beam, and welt to steel flange to anchor U-shaped main bar of SRC structure end to easy stress flow between the different type structure. Through the series of experiments, proposed to possibility of this joint model, and investigated joint rigidity and capacity.

• Fire Science and Engineering
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• v.24 no.2
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• pp.31-37
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• 2010

Asymmetric Slimfloor Beam (ASB) is a composite beam developed in Europe whose asymmetric H beam is partially inserted in concrete slab. Recently in Korea, Asymmetric Slimfloor Beam has been studied in order to save the story height of a building, reduce the amount of construction materials and increase the fire resistance of a building. On this study, the fire resistance of Asymmetric Slimfloor Beam was checked by a fire test and moment capacity was calculated at fire resistance time by a heat-transfer analysis. Using the analysis result, 3-hour fire resistance constructions consisted of fireproof gypsum boards and ASB were selected and fire resistances of selected constructions were checked.

• The Journal of Korean Physical Therapy
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• v.12 no.2
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• pp.133-144
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• 2000

The purpose of this study was to determine whether respiratory physical therapy might increase the pulmonary function of the patients with stroke or not. Twenty patients with stroke were randomly assigned to experimental and control group. During four weeks, both groups participated in the conventional physical therapy and only the experimental group added in a program of respiratory physical therapy. Respiratory physical therapy consisted of chest mobilization, resistive ventilatory muscle training used the method of PNF technique and relaxed diaphragm breathing. Baseline and post-test measurements were made of vital capacity. inspiratory capacity, expiratory reserve volume, farced vital capacity, forced expiratory volume at one second, $FE1/FVC(\%)$ and maximal voluntary ventilation. Ater four weeks, the experimental group showed the significant improvement in VC(p<.05). FVC(p<.05), FFV1(p<.05) md MVV(p<.05). However, the controll group showed no significant differnece. As compared th the relationship of dependent variables between the experimental group and control group. experimental group showed the significant difference in VC(p<.01), FEV1(p<.05) and MVV(p<.05). These findings suggest that respiratory physical therapy can be used to improve pulmonary function in stroke patients. Also, respiratory physical therapy should be performed for at least four weeks and be followed by the continuous respiratory exercise programs.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.395-405
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• 2020

This study examines the relationships and the impacts of service quality, customer satisfaction and switching costs on customer loyalty of e-banking in commercial banks. This study uses questionnaires with 7-point Likert scale to collect data from 227 e-banking users, who are mainly students and paid employees in Hanoi City, Vietnam. The collected data are analyzed by using multivariate linear regression method. The results show that all five factors of service quality in e-banking - reliability, responsiveness, service capacity, empathy and tangibility - have positive correlations with customer satisfaction. Among these determinants, service capacity and tangibility have the strongest impact. It means that, by increasing the quality of their services through five above factors, especially through improving capacity and tangibility, commercial banks can satisfy their customer better. In addition, customer satisfaction is strongly and positively correlated to customer loyalty. It means that, if customers are satisfied with e-banking services of one bank, they not only continue to do more businesses with this bank, but also recommend this bank to other people. Lastly, customer loyalty also has a strong and positive correlation with switching costs, which means customers tend to be loyal to one bank if the barriers to switching banks increase.

• Structural Engineering and Mechanics
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• v.74 no.1
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• pp.145-156
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• 2020

There are separate merits and demerits to wood and steel. The combination of wood and steel as a compound section is able to improve the properties of both and ultimately increase their final bearing capacity. The composite cross-section made of steel and wood has higher hardness while showing more ductility and the local buckling of steel is delayed or completely prevented. The purpose of this study is to investigate the behavior of composite columns enclosed in wooden logs and the hollow sections of steel that will be examined in a laboratory environment under the axial load to determine the final bearing capacity and sample deformation. In terms of methodology, steel sheet and carbon fiber reinforced polymer sheet (FRP) are tested to construct hollow rectangular sections and reinforce timber. Besides, the method of connecting hollow sections and timber including glue and screw has been also investigated. As a result, timber lumber enclosed with carbon fiber-reinforced polymer sheets in which fibers are horizontally located at 90° are more resistant with better ductility.

• Korean Journal of Health Education and Promotion
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• v.25 no.4
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• pp.67-82
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• 2008

Purpose: The objective of this study were to examine the determinants of self-rated health, specially focused on the effect of functional capacity of community dwelling sedentary older adults on self-rated health. Method: The data has been collected from 654 community-dwelling sedentary older adults (mean age: 75 years) during the period from April to June in 2007. The data were collected by the in-person interview and direct measurement of functional capacity. The data were analyzed using chi-square test and multiple regression analysis with the SPSS 9.1 program. Result: The elderly rated their health as very good (3%), good (28%), fair (38%), poor (29%0, and very poor (2%). The higher average daily walk minutes ($\beta$=0.12, p<.01), number of chair stand ($\beta$=0.10, p<.05), scores of self-efficacy ($\beta$=0.16, p<.001) and the lower number of disease ($\beta$=-0.44, p<.001) show better self-rated health. Conclusion: Self-rated health is the most commonly used indicators in social epidemiology and geriatric research because it has been known as the good predictor of mortality and reflects health related disability. The finding suggested that daily walking habits, lower body strength, physical self-efficacy should be considered to improve the senior's self-perception of health. The community-based intervention associate increase these factors should be considered.