• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.201-209
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• 2010

Generally, PSC girder bridge uses total gross cross section to resist applied loads unlike reinforced concrete member. Also, it is used as short and middle span (less than 30 m) bridges due to advantages such as ease of design and construction, reduction of cost, and convenience of maintenance. But, due to recent increased public interests for environmental friendly and appearance appealing bridges all over the world, the demands for longer span bridges have been continuously increasing. This trend is shown not only in ordinary long span bridge types such as cable supported bridges but also in PSC girder bridges. In order to meet the increasing demands for new type of long span bridges, PSC hollow box girder with H-type steel as compression reinforcements is developed for bridge with a single span of more than 50 m. The developed PSC girder applies compressive prestressing at H-type compression reinforcements using unbonded PS tendon. The purpose of compressive prestressing is to recover plastic displacement of PSC girder after long term service by releasing the prestressing. The static test composed of 4 different stages in 3-point bending test is performed to verify safety of the bridge. First stage loading is applied until tensile cracks form. Then in second stage, the load is removed and the girder is unloaded. In third stage, after removal of loading, recovery of remaining plastic deformation is verified as the compressive prestressing is removed at H-type reinforcements. Then, in fourth stage, loading is continued until the girder fails. The experimental results showed that the first crack occurs at 1,615 kN with a corresponding displacement of 187.0 mm. The introduction of the additional compressive stress in the lower part of the girder from the removal of unbonded compressive prestressing of the H-type steel showed a capacity improvement of about 60% (7.7 mm) recovery of the residual deformation (18.7 mm) that occurred from load increase. By using prestressed H-type steel as compression reinforcements in the upper part of cross section, repair and rehabilitation of PSC girders are relatively easy, and the cost of maintenance is expected to decrease.

• Journal of the Korean Society of Radiology
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• v.14 no.3
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• pp.203-209
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• 2020

The purpose of this study is to assess the mechanical stability and alignment of the patient positioning system (PPS) of Leksell Gamma Knife Perfexion(LGK PFX). The alignment of the PPS of the LGK PFX was evaluated through measurements of the deviation of the coincidence of the Radiological Focus Point(RFP) and the PPS Calibration Center Point(CCP) applying different weights on the couch(0, 50, 60, 70, 80, and 90 kg). In measurements, a service diode test tool with three diode detectors being used biannually at the time of the routine preventive maintenance was used. The test conducted with varying weights on the PPS using the service diode test tool measured the radial deviations for all three collimators 4, 8, and 16 mm and also for three different positions of the PPS. In order to evaluate the alignment of the PPS, the radial deviations of the correspondence of the radiation focus and the LGK calibration center point of multiple beams were averaged using the calibrated service diode test tool at three university hospitals in Busan and Gyeongnam. Looking at the center diode for all collimators 4, 8, and 16 mm without weight on the PPS, and examining the short and long diodes for the 4 mm collimator, the means of the validation difference, i.e., the radial deviation for the setting of 4, 8, and 16 mm collimators for the center diode were respectively measured to 0.058 ± 0.023, 0.079 ± 0.023, and 0.097 ± 0.049 mm, and when the 4 mm collimator was applied to the center diode, the short diode, and the long diode, the average of the radial deviation was respectively 0.058 ± 0.023, 0.078 ± 0.01 and 0.070 ± 0.023 mm. The average of the radial deviations when irradiating 8 and 16 mm collimators on short and long diodes without weight are measured to 0.07 ± 0.003(8 mm sd), 0.153 ± 0.002 mm(16 mm sd) and 0.031 ± 0.014(8 mm ld), 0.175 ± 0.01 mm(16 mm ld) respectively. When various weights of 50 to 90 kg are placed on the PPS, the average of radial deviation when irradiated to the center diode for 4, 8, and 16 mm is 0.061 ± 0.041 to 0.075 ± 0.015, 0.023 ± 0.004 to 0.034 ± 0.003, and 0.158 ± 0.08 to 0.17 ± 0.043 mm, respectively. In addition, in the same situation, when the short diode for 4, 8, and 16 mm was irradiated, the averages of radial deviations were 0.063 ± 0.024 to 0.07 ± 0.017, 0.037 ± 0.006 to 0.059 ± 0.001, and 0.154 ± 0.03 to 0.165 ± 0.07 mm, respectively. In addition, when irradiated on long diode for 4, 8, and 16 mm, the averages of radial deviations were measured to be 0.102 ± 0.029 to 0.124 ± 0.036, 0.035 ± 0.004 to 0.054 ± 0.02, and 0.183 ± 0.092 to 0.202 ± 0.012 mm, respectively. It was confirmed that all the verification results performed were in accordance with the manufacturer's allowable deviation criteria. It was found that weight dependence was negligible as a result of measuring the alignment according to various weights placed on the PPS that mimics the actual treatment environment. In particular, no further adjustment or recalibration of the PPS was required during the verification. It has been confirmed that the verification test of the PPS according to various weights is suitable for normal Quality Assurance of LGK PFX.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.1
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• pp.69-78
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• 2013

Recently, as GIS industry has substantially grown up, convergence between industries such as the application coverage of surveying and cadastral information is gradually on the increase. The new approach of convergence between topographic surveying and cadastral survey is indispensable to make the change of geospatial environment ready and to maximize the utilization of National Spatial Data Infrastructure(NSDI). The purpose of this paper is to seek the way of synergistic improvement in topographic surveying and cadastral survey in comprehensive aspects of national geospatial information. First, we reviewed policy environment to clearly establish aim of convergence and promising perspective of GIS industry policy, considering NSDI. In addition, we examined current state of administration (organization, human resource, service) and institution situation. We came up with interior ability and external policy environment as well as critical success factor for the synergistic convergence by using SWOT analysis. Lastly, we developed basic perspective of convergence and improvement model and concrete scheme for stakeholder to complementary make progress. We can come to conclusion that the convergence of topographic surveying and cadastral survey should be not only carried in macro outline of successful NSDI but also committed to completion and maintenance of GIS framework.

• Journal of dental hygiene science
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• v.11 no.4
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• pp.353-359
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• 2011

This study was designed to identify a subjective symptom level by Indoor air according to ventilation system in Dental Clinic. The number of respondents was 582 who work in dental clinic and period of investigation was October 2010 through January 2011. A structured questionnaire was employed to evaluate the level of participants' sociodemographics, job-related factors, work place condition, a subjective symptom. Most of respondents were answered that time for symptom to begin was at around 2 P.M. and time for symptom to feel serve pain was at around 3 P.M. and ventilation frequency per a day was often in case of individual cooling and heating system. More often natural ventilation and in case of individual cooling and heating system, the level of subject symptom was low and multiple regression analysis has found that indoor air quality related elements were main factors that influence to the feeling of satisfaction in work place. The results of this study suggest that more often natural ventilation was very important to reduce the level of subjective symptom. Thus, a management program for indoor air quality is strongly recommended by natural ventilation, maintenance man for promotion of quality of life in dental hygienist and to improve dental service and competitiveness.

• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.265-286
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• 2013

The present study was conducted to develop a standardized job description for clinical dietitians working in hospitals. A developing curriculum (DACUM) method was used for the job analysis of clinical dietitians. Based on DACUM analysis with 14 members, including clinical dietitians and professors majoring in clinical nutrition and job analysis, information on the duties, tasks, and task elements of clinical dietitians was determined. To verify the job descriptions derived from DACUM analysis, a total of 46 tertiary and general hospitals with over 500 beds were recruited for the survey. The final developed job description for clinical dietitians included 7 duties, 27 tasks, and 93 task elements. The duties consisted of nutritional assessment, nutrition diagnosis, nutrition intervention, nutrition monitoring evaluation, consultation cooperation, nutrition research, and self-development. The mean scores of perceived importance, performance, and difficulty on the clinical dietitian's task elements (out of a maximum score of 5.0) were 4.5, 3.7, and 3.5, respectively, with significant differences between the items (P<0.001). The perceived importance and performance grid of clinical dietitian's tasks showed that "construction and maintenance of collaboration" (E2) and "activity of quality improvement" (F1) received relatively low scores for performance despite their high importance scores; thus the performance of these tasks requires significant improvement. In conclusion, the job descriptions of clinical dietitians developed from this study are useful for the qualitative improvement of clinical nutrition services in hospitals.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.71-80
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• 2013

According to design specifications for structural safety, a bridge in initial design step has been modelled to have larger self-weight, external loads and less stiffness than those of real one in service. Thereby measured buffeting responses of existing bridge show different distributions from those of the design model in design step. In order to obtain accurate buffeting responses of the in-site bridge, the analysis model needs to be modified by considering the measured natural frequencies. Until now, a Manual Tuning Method (MTM) has been widely used to obtain the Measurement-based Model(MBM) that has equal natural frequencies to the real bridge. However, since state variables can be selected randomly and its result is not apt to converge exact rapidly, MTM takes a lot of effort and elapsed time. This study presents Buffeting Response Correction Method (BRCM) to obtain more exact buffeting response above MTM. The BRCM is based on the idea the commonly used frequency domain buffeting analysis does not need all structural properties except mode shapes, natural frequencies and damping ratio. BRCM is used to improve each modal buffeting responses of the design model by substituting measured natural frequencies. The measured natural frequencies are determined from acceleration time-history in ordinary vibration of the real bridge. As illustrated examples, simple beam is applied to compare the results of BRCM with those of a assumed MBM by numerical simulation. Buffeting responses of BRCM are shown to be appropriate for those of in-site bridge and the difference is less than 3% between the responses of BRCM and MTM. Therefore, BRCM can calculate easily and conveniently the buffeting responses and improve effectively maintenance and management of in-site bridge than MTM.

• Information Systems Review
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• v.14 no.1
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• pp.67-84
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• 2012

Recent increases in uncertainty and speed of market change are driving the adoption of new intelligent mobile office systems. Organizational information systems paradigm suggests that a right match between organizational characteristics and the use of technology is critical in producing desired results. Following such perspective this study developed the mobile office system case of Seoul Metropolitan Railway Transit(SMRT) in Korea. SMRT developed the mobile task-supporting environment that help the management of subway lines real-time without the restriction of time and space. They named the system as ST&F(SMRT Talk and Flash). They decided to develop the application systems in-houses they did not want to be overly dependent on external services in future changes and developments of the system. The new practice reduced the time for moving back and forth to 10% of their working time from previous 20%. The time used for paper works and administration chore also reduce to 10% of their working time from previous 30% on the average. The employees could use 80% of their time to concentrate on the completion of assigned task. The effects of this improvement resulted in the heightened efficiency of the use of human resources and the heightened level of railway safety. The case of SMRT shows that the mobile office system can be applied and extended to various business areas such as facility management and maintenance beyond such typical uses as sales and marketing support. Also, The result of case study will be a useful guideline on the construction and using of mobile office system.

• The Journal of Society for e-Business Studies
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• v.22 no.3
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• pp.57-74
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• 2017

The Electronic Shelf Label (ESL) is an alternative to the paper price label attached to merchandise shelves and is attracting attention as a retail IoT infrastructure that will lead the innovation of offline retail outlets. In general, when introducing a substitute product, the company tends to consider the financial factors such as the efficiency of the investment cost compared to the existing product or the reduction of the operating cost. However, considering only financial factors in the decision-making process, it may not properly reflect the various values associated with corporate strategy and the requirements of stakeholders. In this study, 8 evaluation items (Investment Cost, Operating Cost, Quality Level, Customer Management, Job Efficiency, Maintenance, Functional Expandability, and Store Image) based on BSC's 4 perspectives (Financial, Customer, Internal Business Process, Learning & Growth), and using AHP (Analytic Hierarchy Process) to measure the priorities of evaluation items for domestic small supermarket employees. As a result of the research, priority was given in order of Customer, Learning & Growth, Internal Business Process, and Financial aspects among the evaluation items for adopting the price label, and the electronic price label was supported with higher importance than the paper price label. In contrast to the priorities of the financial aspects of most prior studies, the items of Learning & growth and customer perspectives have relatively high priorities. In particular, respondents classified by job group, The priorities of the 8 evaluation items were different among the groups. These results are expected to provide implications for both companies (retail outlets) and ESL providers (manufacturers and service providers) who are considering the introduction of ESL.

• Therapeutic Science for Rehabilitation
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• v.3 no.1
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• pp.31-37
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• 2014

Objective : The purpose of this study was to look at a systematic review on the effects of occupational reminiscence therapy in Dementia offered National Long term care Insurance. Through this comprehensive study, we have to compare the studies. Methods : We systematically examined papers published in journal from 2009 to 2013, using KERIS. Main words to examine are Dementia, Long term care service, Day care center, reminiscence therapy, occupational centered, etc. Results : 6 studies were selected, All of them were occupational reminiscence therapy. Reminiscence therapy can be devided into communication centered reminiscence therapy and occupational reminiscence therapy. The results demonstrated that the intervention significantly affected the maintenance cognitive skills and reminiscence skills, decreased depression, behavioral changes, improvement of communication and interaction skills and quality of life etc. of elderly people with dementia (p<.05). Conclusions : If occupational therapists can obtain knowledge and make a program for occupational reminiscence therapy, research in this field will be further developed. In the future study, the use of occupational reminiscence therapy applied to a variety of interventions and majority of patients is needed on occupational therapy.

• Fire Science and Engineering
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• v.31 no.1
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• pp.116-123
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• 2017

The purpose of this paper is to improve the evacuation stability of residents in apartment fire. For this purpose, the actual condition survey about the obstacles was conducted on 3,056 escape stairs in the 183 apartments. In addition, the questionnaire investigation was carried out a survey targeting the residents of apartments about their experience of fire safety education, perception on safety management of escape stairs, and perception on fire safety. As a result of investigation, we confirmed that the obstacles were formed in the 1,916 escape stairs among the 3,056 escape stairs of the 183 apartments (percent of barricades in escape stairs: 62.70%). Furthermore, it showed that fire safety education experience was found to be 83.10% of subject. The perception on safety management of the subjects in the escape step and the perception on fire safety were $3.84{\pm}0.75%$, and $3.49{\pm}0.61$, respectively. In the results, most of the subjects had a fire safety education and knew how to safety management the escape stairs but, the practice of the safety management action was low. Based on the results in the paper, the policy proposal is that the fire safety education is emphasized to change from the perception to action.