• Structural Engineering and Mechanics
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• v.14 no.3
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• pp.331-343
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• 2002

Because of the increasing span of arch bridges, ultimate capacity analysis recently becomes more focused both on design and construction. This paper investigates the static and ultimate behavior of a long-span steel arch bridge up to failure and evaluates the overall safety of the bridge. The example bridge is a long-span steel arch bridge with a 550 m-long central span under construction in Shanghai, China. This will be the longest central span of any arch bridge in the world. Ultimate behavior of the example bridge is investigated using three methods. Comparisons of the accuracy and reliability of the three methods are given. The effects of material nonlinearity of individual bridge element and distribution pattern of live load and initial lateral deflection of main arch ribs as well as yield stresses of material and changes of temperature on the ultimate load-carrying capacity of the bridge have been studied. The results show that the distribution pattern of live load and yield stresses of material have important effects on bridge behavior. The critical load analyses based on the linear buckling method and geometrically nonlinear buckling method considerably overestimate the load-carrying capacity of the bridge. The ultimate load-carrying capacity analysis and overall safety evaluation of a long-span steel arch bridge should be based on the geometrically and materially nonlinear buckling method. Finally, the in-plane failure mechanism of long-span steel arch bridges is explained by tracing the spread of plastic zones.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.138-146
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• 2007

Objective : To observe the trend in clinical study on atopic dermatitis(AD) over the last 3 years in order to develop a study methodology of AD in Oriental Medicine. Methods : Using the Pub med on line site; search terms: atopic dermatitis, field as title/abstract, limitation as published in the last 3 years, only items with links to full text, Humans, Clinical Trial, English. I observed the study contents of all this research and focused on the classification of treatments. I also observed of AD clinical trials registered on a clinical trial site(www.clinicaltrial.gov) on 23rd of June, 2007: study contents, localization and study designs. Results : Through the Pub Med site, I found 169 articles. Classified according to study subject, the studies related to treatment were 114(67.5%); physiology, pathology and prevention 12(7.1%); Diagnosis and Evaluation(7.1%); psychological aspects including quality of life 10(5.9%); diet and management 10(5.9%); epidemiology 7(4.1%); and others 7(4.1%). However, the treatment study of herb-medicine as intervention showed only 1 article. Futhermore, it wasn't based on Oriental Medicine philosophy. In the clinical trial site, there were 31 studies in which patients were recruited or planned for the future. The study on efficacy and safety of the medicine produced 14 trials, 5 comparative trials, 2 phototherapy, 2 diagnosis, 6 physiology and pathology, and 2 epidemiology. The trial institutions were concentrated in U.S.A. Conclusion : I suggest we'd better try to make a good clinical guideline and standardization of diagnosis and herb-medicine in order to develop a clinical study methodology of AD as soon as possible in the future. Even though it 's very hard to find the study methodology, we should aim to achieve positive results and show the evidence of the efficacy and safety of herb-medicine treatment for AD using Oriental Medicine.

• Journal of Auto-vehicle Safety Association
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• v.11 no.4
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• pp.6-15
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• 2019

Since introducing the offset frontal impact test in EuroNCAP in 1997, the vehicle has been constantly changing according to its usage and purpose. As of 2019, many vehicles have been released to the public, which has led to a large structural mass difference between small, medium and large vehicles. Also, the geometry of the front of the vehicle is completely different for each vehicle and tends not to be perfectly aligned at frontal collisions. The difference in mass of each of these vehicles and less performing structures for offset crashes have led to dramatically worse outcome in a car to car offset frontal impact tests. Even though a decade later passenger cars have become much safer due to consumer test programs and regulatory requirements, the aggressiveness and compatibility that can cause damage to the opponent car in the event of car to car collision is not considered in the above-mentioned section, and therefore much improvement is needed. After many years of study to solve this problem, EuroNCAP has developed a new mode MPDB offset front test that considers the aggressiveness and compatibility that can affect the opponent cars that have collided. This paper introduces the development process of aggressiveness and compatibility evaluation method of MPDB in EuroNCAP which will be implemented from 2020. Several impact tests have been conducted at different test conditions to rate the vehicle structure performance only focused on aggressiveness and compatibility of MPDB.

• The Journal of Pediatrics of Korean Medicine
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• v.35 no.3
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• pp.67-88
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• 2021

Objectives The purpose of this study is to analyze randomized clinical trials (RCTs) on traditional Chinese medicine to summarize its efficacy and safety for the treatment of functional gastrointestinal disorders (FGIDs) in children. Methods We searched literatures published up to March 19, 2021 using two Chinese electronic databases. Data regarding patients, interventions, results, and adverse events were extracted from RCTs of herbal medicine for children with FGIDs. Results A total of 34 RCTs were included: 16 trials on functional dyspepsia, 7 trials on functional constipation, 6 trials on functional abdominal pain, 4 trials on irritable bowel syndrome, and 1 trial on functional diarrhea. 26 of 29 trials that reported total effective rate, the treatment group showed a significant improvement compared to the control group. Most of other evaluation indicators, such as symptom score, symptom disappearance time, and recurrence rate also demonstrated statistically significant improvement. Of the 16 studies which reported safety, 5 studies reported no adverse reactions in either group, and 4 studies reported no statistically significant differences in the incidence of adverse events between two groups. Also, reported adverse events were mostly mild. Conclusions Herbal medicine may help improve symptoms of FGIDs in children. However, due to limited types of studies on sub-diseases of FGIDs and small sample sizes in each study, additional large scale clinical studies on various other FGIDs are necessary.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.8
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• pp.783-789
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• 2012

In this study, turbulent flow and heat transfer characteristics in a helically coiled tube have been numerically investigated. Helically coiled tubes are commonly used in heat exchange systems to enhance the heat transfer rate. Accordingly, they have been widely studied experimentally; however, most studies have focused on the pressure drop and heat transfer correlations. The centrifugal force caused by a helical tube increases the wall shear stress and heat transfer rate on the outer side of the helical tube while decreasing those on the inner side of the tube. Therefore, this study quantitatively shows the variation of the local Nusselt number and friction factor along the circumference at the wall of a helical tube by varying the coil diameter and Reynolds number. It is seen that the local heat transfer rate and wall shear stress greatly decrease near the inner side of the tube, which can affect the safety of the tube materials. Moreover, this study verifies the previous experimental correlations for the friction factor and Nusselt number, and it shows that the correlation between the two in a straight tube can be applied to a helical tube. It is expected that the results of this study can be used as important data for the safety evaluation of heat exchangers and steam generators.

• Korean Institute of Interior Design Journal
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• v.24 no.4
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• pp.23-32
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• 2015

This research tried identifying the current status of Gyongrodangs to find solutions to the problems of the oldest old through revitalization of the existing senior centers. With 31 national and public Gyungrodangs in Seocho-gu, Seoul as research subjects, the research contents include a survey of the facilities including main exit doors, living rooms and lounges, kitchens, and rest rooms in the Gyungrodangs by the checklist, and as the research tool a laser finder, measuring tapes, and cameras were used. The checklist was used as the research method to investigate main exit doors, living rooms and lounges, kitchens, and rest rooms. Based on the research results, the following conclusions are presented. The safety-related items of the public Gyungrodang facilities were reaching a critical level. They need to equip emergency exit routes, install exit lights and alarm bells, and teach how to use them. After that, the issue of rest room would be raised; the oldest old had difficulty in using the rest room with no consideration of universal design(UD), so installation of grab bars is needed around toilets, washstands, and urinals. Besides them, although absence of the western style furniture without consideration of users' ages caused inconvenience of using, there are no solutions due to the limited space. Unnecessary equipment such as treadmills which only occupy spaces without users should be thrown away and replaced with the furniture people would use like tables with supplement of furnitures to lie down and rest. Overall, the current Gyongrodang Facilities lack systems and need standardized management, in which the checklist this researcher developed and used in evaluating the present conditions could be recommended. It is expected that the evaluation system of senior centers would be arranged through this checklist, so that systematic service supply could be possible in the better facility environment.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.195-202
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• 2008

Underestimation of the capacity can have serious economic consequences, as deficient bridges must be posted, repaired or replaced. Accurate prediction of bridge behavior may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Reliability analysis is performed on 17 previously tested bridges. Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased due to the reduction of uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.2
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• pp.34-49
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• 1993

This research aimed to analize the cognitive intensity of valuation(C.I.V) on urban environment as a first stage of the works on evaluative urban image under the hypothesis that it could be interpreted with a correlation analysis between the C.I.V and attitude(Satisfaction of unsatisfaction Intensity) toward urban environment. As a method of a study, 118 cognitive elements were selected representing an urban environment, and each of elements was suggested to citizens of Kyungju with 7 point Likert Scale. The analysis of C.I.V was operated under the three criteria: The first, three of urban space scale(urban scale, neighborhood scale, and housing scale), the second, four elements of urban living environment(safety, amenity, healthfulness, and effectiveness), and the last, thirteen urban unit environment(housing, traffic, education, tourism, medical/health, culture, etc.). The results were as follows: C.I.V to each of 118 elements was cleary defined, showing the possibilities of being applied to a method for subjective, or cognitive evaluation on urban environment: It was revealed that citizens'C.I.V was rather higher in non-physical, qualitative elements than in physical and quantitative ones. This shows well the limitation of the objective method of evaluation of urban environment: The results of the others' studies on the image of Kyungju based on the cognitive approach, being focused on the analysis of the visual aspects of urban structure, cultural assets, historic site and tourism, were almost same as this study but it was quite different for this research to reveal well the citizens' cognition on their living environment of traffic, education, medical, etc..

• Journal of Korean Society of Steel Construction
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• v.20 no.1
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• pp.93-104
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• 2008

study deals with the reliability assesment for the 5-year phases of a suspension bridge construction in Korea. The main objectives of this study are; (1) the evaluation of the reliability of a suspension bridge by considering an ultimate limit state for the fracture of main cable wires, (2) the determination of the critical phases among 28 construction stages for the deck erection, and (3) the evaluation of the reliability of the limit state for the erection control during construction stages. The research and the design of the suspension bridge have been focused on the state of construction mainly based on empirical data. Based on the recent survey of the distribution of accidents in Korean railways, over 80% of the accidents related to the uncertainties in human error, planning, design, materials and loads during construction have ben reported before the completion of construction. While many researches have evaluated the safety of bridges, the uncertainties in the construction phases have not been well treated in a guidelines or a specifications. An improved adaptive response surface method is used for the risk assessment in the construction phases of the target suspension bridge.

• The Journal of Korean Academic Society of Nursing Education
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• v.29 no.4
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• pp.381-394
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• 2023

Purpose: This study aimed to develop an intentional rounding protocol to enhance the clinical competence of nursing students. Methods: An intentional rounding protocol for nursing students' clinical practice was developed following the ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model. A convenient sampling method was used to select 23 junior year university nursing students during their clinical practice in adult nursing. The program evaluation included a quantitative assessment (communication and relationship efficacy, empathy, and patient safety competency) and focus group interviews. Results: The intentional rounding protocol focused on the 4Ps (pain, position, potty, and possessions) and encompassed aspects such as level of consciousness, pain management, personal care needs, intravenous injection, oxygen administration, nasogastric/nasoenteric tube care, maintenance of urine collection bags, and the identification of environmental fall risks. Nursing students performed intentional rounding at least twice a day. Following the implementation of this protocol, nursing students demonstrated a significant improvement in communication and interpersonal efficacy. The focus group interviews revealed four main themes: growth of human relationships, acquiring knowledge in and about the clinical field, becoming a nurse, and barriers in reality. Conclusion: The intentional rounding protocol has the potential to enhance nursing students' communication and interpersonal skills during clinical practice and to provide them with positive experiences in nursing clinical education. Therefore, it is recommended that this protocol be incorporated into nursing clinical practice education.