• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.393-399
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• 2007

Concrete bridge decks are directly exposed to the severe environmental conditions such as rain water and deicing chemicals resulting in the freeze-thaw action and the rebar corrosion during their service lift. These deteriorations of bridge decks shorten the service lift and consequently they are the major concerns of the maintenance. The high performance concrete (HPC) deck is proposed as the alternative to minimize the deterioration problems. To develop more durable concrete deck, the performance characteristic tests of HPC mixtures were carried out. In this study, 4 different concrete mixtures were used varying the mineral admixtures as the cement replacement; ordinary portland cement (OPC), 20% fly ash (FA),20% fly ash with 4% silica fume (FS), and 40% ground granulated blast-furnace slag (BS). The design compressive strengths of HPC specimens were 27 MPa and 35 MPa, respectively. The results showed that the compressive strength of concrete did not much affect the durability of concrete. HPC with fly ash and silica lune (FS) were turned out to have the good durability and crack resistance.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.375-381
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• 2008

Various problems such as durability degradation may happen when extra water is added to concrete. Because of these reasons, the change of water content is managed by using rapid evaluation method of unit water content such as electric capacity method, heat drying method making use of micro wave, unit capacity mass method among various methods. Especially, in Japan, guidance for the change of water content ($\pm$ 10, 15, 20 kg/$m^3$ etc.) were regulated and used. However, it is the real situation that the guidance which were regulated in South Korea evaluate suitability only considering production and measurement error under the circumstances which are not considering the degree of durability degradation. Therefore, this study tries to investigate the influence of addition of extra water in the concrete on the durability degradation of concrete when it was added by artificial manipulation or by management error. From the test results, a guideline of the contents of extra water for the quality control is suggested with the consideration of the degree of durability degradation and the probable error resulted from the addition of extra water. The contents of extra water for tests are set as 0, 15, 25, 35 kg/$m^3$. To examine the durability degradation of concrete, freezing and thawing, carbonation, chloride penetration and compressive strength are tested.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.295-304
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• 2013

Ultra-High Performance Concrete (UHPC) has recently been one of the most active research fields in Korea as well as in foreign countries, because it can contribute to a longer life and economic efficiency of structures. Although precast-type UHPC fabricated in a factory is preferable in terms of quality control and reduction of construction period, there exist, even in the precast structure, some parts that need to be cast in-place such as the joints between precast segments. In the cast-in-place UHPC, however, it is probable that an optimum curing condition can hardly be realized in contrast to the factory production. In this study, therefore, the trend of compressive strength development of UHPC was experimentally investigated by assuming various inferior curing conditions that may be anticipated at a construction site. Concrete specimens were fabricated and cured under different conditions with the variables such as curing temperature, delay time before the initiation of curing, duration of curing time and moisture condition. The strengths were compared with those of the specimens cured by standard high temperature steam. Through the analysis of the test results, some minimum requirements for curing have been proposed that are required when the UHPC is cast in-place. It is expected, through this study, that practical use of UHPC in construction sites can be increased.

• The Journal of Korean Academic Society of Nursing Education
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• v.5 no.2
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• pp.267-284
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• 1999

The purpose of this study are 1. Evaluate the degree of knowledge of Vaginal Birth After Cesarean(VBAC) of Korean nurses. 2. To gather and develop educational material for VBAC. The sample was surveyed Korean Nurses knowledge about VBAC, from November 1998 through March 1999. For the data analysis, the SPSS computer program percentage and frequency were used for descriptive statistics. The x2 and the t-test were used to compare the results of the two sample groups. Open questions asked in the survey were sorted out by content, then displayed in chart form. For the education material, the Internet was the main source of information. Information on the Internet was provided by professional doctors and prenatal educational nurses. The results of the survey are as follows: 1. Out of 97 Nurses 15.3% answered that cesarean deliveries do not need to be performed after previous cesarean sections : however. 46.4% answered that cesarean sections must be performed after previous cesarean sections. 2. Of the nurses surveyed 14% had no knowledge or had never heard of VBAC. 3 Nurses did not have questions from patients concerning VBAC was 34.7%. This led to the conclusion that patients either do not have knowledge about VBAC or patients have no interest in the trial of labor. 4, Nurses indicated that their information about VBAC originated from other people's experiences (31%), Nursing School (25%), Media information (9%), and through literature review (6%). This data led to the conclusion that the knowledge about VBAC may not be extensive enough to counsel and guide patients who are willing to endure the trial of labor. 5. Nurses preferred hospital education programs to develop their knowledge concerning VBAC. Based upon survey, the conclusion was made that General Nurses and Maternity Nurses did not have knowledge about VBAC success rates and the possibility of a trial of labor. In order for nurses to help patients make decisions concerning VBAC, nurses have to gam more knowledge through hospital educational programs. Further more, the study suggests that through hospital educational programs, the possibility and importance of VBAC must be emphasized to nurses who work in maternity areas. Second, through prenatal educational programs, the possibility and importance of VBAC must be explained and emphasized to patients who had previous cesarean sections. Third, the clinical pathways of VBAC need to be developed. Fourth, each hospital needs to develop multi-disciplinary teams, consis-ting of obstetricians, risk management/quality management, staff registered nurses, and the director for perinatal services. This team can review cesarean section rates and help to increase the practice of VBAC.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.164-173
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• 2014

In underwater robotics, vision would be a key element for recognition in underwater environments. However, due to turbidity an underwater optical camera is rarely available. An underwater imaging sonar, as an alternative, delivers low quality sonar images which are not stable and accurate enough to find out natural objects by image processing. For this, artificial landmarks based on the characteristics of ultrasonic waves and their recognition method by a shape matrix transformation were proposed and were proven in Part 1. But, this is not working properly in undulating and dynamically noisy sea-bottom. To solve this, we propose a framework providing a selection phase of likelihood candidates, a selection phase for final candidates, recognition phase and tracking phase in sequence images, where a particle filter based selection mechanism to eliminate fake candidates and a mean shift based tracking algorithm are also proposed. All 4 steps are running in parallel and real-time processing. The proposed framework is flexible to add and to modify internal algorithms. A pool test and sea trial are carried out to prove the performance, and detail analysis of experimental results are done. Information is obtained from tracking phase such as relative distance, bearing will be expected to be used for control and navigation of underwater robots.

• Spatial Information Research
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• v.21 no.3
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• pp.45-53
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• 2013

Web GIS, based on the latest web-technology, has evolved to provide efficient and accurate spatial information to users. Furthermore, Web GIS Server has improved the performance constantly to respond user web requests and to offer spatial information service. This research aims to create a designed and implemented Web GIS Server that is named as Nodemap which uses the emergent technology, Node.js, which has been issued for an event-oriented, non-blocking I/O model framework for coding JavaScript on the server development. Basically, NodeMap is Web GIS Server that supports OGC implementation specification. It is designed to process GIS data by using DBMS, which supports spatial index and standard spatial query function. And NodeMap uses Node-Canvas module supported HTML5 canvas to render spatial information on tile map. Lastly, NodeMap uses Express module based connect module framework. NodaMap performance demonstration confirmed a possibility of applying Node.js as a (next/future) Web GIS Server development technology through the benchmarking. Having completed its quality test of NodeMap, this study has shown the compatibility and potential for Node.js as a Web GIS server development technology, and has shown the bright future of internet GIS service.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.246-253
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• 2012

In this study, we determined the optimum blanching conditions for pretreatment of Aster scaber prior to freezing to ensure its long, safe preservation as a fine cooking ingredient. Frozen-thawed A. scaber did not significantly differ between blanching groups, but the blanched group showed significantly higher Hunter L, a, and b values than the un-blanched group (p<0.05). Higher temperatures and longer treatment times increased softness; hardness did not significantly differ between the blanched and un-blanched groups of frozen-thawed A. scaber (p<0.05). Total bacterial counts and the presence of coliforms seemed to decline with blanching treatments, but treatment temperature and time did not influence this reduction. Over 95% of peroxidase activity was inactivated by blanching treatment but increased slightly after thawing. The sensory evaluation of the frozen-thawed A. scaber by test group showed the A. scaber blanched at $90^{\circ}C$ for 3 min to be the most highly preferred (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.10
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• pp.1608-1617
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• 2013

This study is performed to evaluate the effectiveness of a weight management program for overweight and obesity office workers; comparing their changes in the anthropometry, biochemistry, nutrient intakes, and exercise performance before and after the obesity management program. This program was performed on 39 workers, who are overweight or obese, over BMI 23 for 6 months in Jeollabuk-do public institution. As the results of this study suggests, triceps thickness (TT) of male subjects was significantly decreased (P<0.05). Waist circumference (WC), and hip circumference (HC) of the total subjects were significantly decreased after the weight management program (P<0.05). The biochemical result of the Total cholesterol (TC) (P<0.05) and LDL cholesterol (LDL-C) (P<0.01) was significantly decreased in male subjects. The results of abdominal computed tomography (CT) also showed that subcutaneous fat area (SFA) of male subjects was significantly decreased after the weight management program (P<0.01). The nutrient intake's results of female subjects, who took Fe, Vit B2, and niacin, were increased significantly after the weight management program (P<0.05). The nutrition knowledge score of male subjects was significantly increased (P<0.05), and a muscular endurance of the physical test was significantly increased after the obesity management program (P<0.01). At the work place, workers need a systemic health and obesity management program to improve their work efficiency and quality of life. After this study, the program should be developed and supported continuously to maintain positive results from this study.

• Tuberculosis and Respiratory Diseases
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• v.81 no.4
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• pp.281-288
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• 2018

Background: There are limited number of studies that investigate clinical variables instead of chronic obstructive lung disease (COPD) management according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 classification. The aim of the study was to investigate whether there was a difference between GOLD 2017 classification and spirometric stage in clinical variables in patients with COPD. The data of 427 male patients with stable COPD were investigated retrospectively. Methods: Patients were allocated into combined assessment of GOLD 2017 and spirometric stage. Age, amount of smoking, pulmonary function, modified Medical Research Council (mMRC), incremental shuttle walk test (ISWT), Hospital Anxiety-Depression Scale (HADS), St. George's Respiratory Questionnaire (SGRQ), body mass index (BMI), and fat free mass index (FFMI) were recorded. Results: Seventy-three (17%) patients were in group A, 103 (24%) constituted group B, 38 (9%) were included in group C, and 213 (50%) comprised group D according to the combined assessment of GOLD 2017. Twenty-three patients (5%) were in stage 1, 95 (22%) were in stage 2, 149 (35%) were in stage 3, and 160 (38%) were in stage 4 according to spirometric stage. According to GOLD 2017, age, amount of smoking, mMRC, BMI, FFMI, SGRQ, HADS, forced vital capacity, forced expiratory volume in 1 second ($FEV_1$), and ISWT were significantly different between groups. Ages, amount of smoking, FFMI, BMI, HADS of group A were different from B and D. Smiliar values of $FEV_1$ were found in A-C and B-D. A and C had smiliar ISWT. According to spirometric stage, BMI, FFMI of stage 4 were statistically different. mMRC, ISWT, and SGRQ of stages 3 and 4 were different from other stages, amongst themselves. $FEV_1$ was correlated with mMRC, SGRQ, anxiety scores, BMI, FFMI, and ISWT. Conclusion: This study showed that the GOLD ABCD classification might not represent the severity of COPD sufficiently well in terms of lung function or exercise capacity. The combination of both spirometric stage and combined assessment of GOLD 2017 is important, especially for estimating clinical variables.

• Information Systems Review
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• v.8 no.3
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• pp.201-223
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• 2006

This study surveys the current state of the art in the field of IT investment and performance in domestic finns and investigates the statistical significance of various hypothesis of previous relevant researches. Data of 145 information systems of 133 firms have been collected. The amount of IT budget in 2005 has increased to the level of 2.53% of gross revenue of the firms and IT business value has also increased as compared to the previous year. As results of MANOVA test, it has been found that the amount of IT budget does not affect the level of IT business value. In other words, the relationship between IT investment and IT business value does not exist. And among ten factors which has been known to determine IT business value in previous researches, only three factors have been found to affect the level of IT business value: the technical quality of information systems, CIO leadership in the context of resource allocation and decision makings, and the capability and commitment of the user department. These finding provide insight for both practitioners and researchers.