• Journal of Radiation Protection and Research
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• v.28 no.2
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• pp.127-135
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• 2003

The primary contributors to the total occupational radiation exposure in operating nuclear power plants are operation and maintenance activities doting refueling outages. The Advanced Power Reactor 1400 (APR1400) includes a number of design improvements and plans to utilize advanced maintenance methods and robotics to minimize the annual collective dose. The major radiation exposure reduction features implemented in APR1400 are a permanent refueling pool seal, quick opening transfer tube blind flange, improved hydrogen peroxide injection at shutdown, improved permanent steam generator work platforms, and more effective temporary shielding. The estimated average annual occupational radiation exposure for APR1400 based on the reference plant experience and an engineering judgment is determined to be in the order of 0.4 man-Sv, which is well within the design goal of 1 man-Sv. The basis of this average annual occupational radiation exposure estimation is an eighteen (18) month fuel cycle with maintenance performed to steam generators and reactor coolant pumps during refueling outage. The outage duration is assumed to be 28 days. The outage work is to be performed on a 24 hour per day basis, seven (7) days a week with overlapping twelve (12) hour work shifts. The occupational radiation exposure for APR1400 is also determined by an alternate method which consists of estimating radiation exposures expected for the major activities during the refueling outage. The major outage activities that cause the majority of the total radiation exposure during refueling outage such as fuel handling, reactor coolant pump maintenance, steam generator inspection and maintenance, reactor vessel head area maintenance, decontamination, and ICI & instrumentation maintenance activities are evaluated at a task level. The calculated value using this method is in close agreement with the value of 0.4 man-Sv, that has been determined based on the experience aid engineering judgement. Therefore, with the As Low As Reasonably Achievable (ALARA) advanced design features incorporated in the design, APR1400 design is to meet its design goal with sufficient margin, that is, more than a factor of two (2), if operated on art eighteen (18) month fuel cycle.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5913-5916
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• 2015

Gestational trophoblastic neoplasia (GTN) is the malignant form of gestational trophoblastic disease. In non-metastatic GTN, the outcomes of treatment are impressive with methotrexate (MTX) or actinomycin D. We retrospectively reviewed the outcomes of non-metastatic GTN treated at our center from January, 1999 to December, 2013. One hundred and nine patients were recruited to the study. The median age was 33.1 years and over 90% were referral cases. Abnormal vaginal symptoms developed in 37.6% while 56.4% were asymptomatic. The most common antecedent pregnancy was a complete mole (92.7%) with the median interval time from antecedent pregnancy to GTN development being 2.0 months. The median pretreatment B-hCG was 5,624 mIu/ml. The most common first line treatment was methotrexate (MTX) and folinic acid (91.7%) followed by weekly MTX (4.6%), etoposide+ MTX+actinomycin D (EMA) (2.8%), and actinomycin D (0.9%), with the median number of cycles at 5.0. The positive response to first line chemotherapy was 73.8%. The patients were given subsequent chemotherapeutic regimens after resistance to the first line therapy and showed a final remission rate of 89.9%.The significant factor that was frequently found in patients who were non-responders to the first line treatment was a hysterectomy procedure. Two patients developed lung metastasis and brain metastasis at one and four years after the first treatment, respectively. In conclusion, the outcomes of non-metastatic GTN were excellent. However, the patients need long term follow up due to the possibility of developing multiple organ metastases.

• Journal of Aerospace System Engineering
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• v.13 no.4
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• pp.50-59
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• 2019

The design of the main control valve, which is the main component of the flap control system, was based on actual manufacturing experience on the basis of trial and error method. In this paper, a model-based part design method is proosed. The flap control system consists of a main control valve, fail-safe valve, solenoid valve, LVDT and force motor. The main control valve consists mainly of a spool and slot. The important design parameters of the main control valve are the slot width, overlap and clearance. AMESim is linked to the model and it analyzes the flow path of the main control valve. Applying the proposed design procedure, it was confirmed that the required performance was satisfied within the allowable machining error range.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.17-25
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• 2023

Purpose: This study aimed to examine the effectiveness of a suicide prevention education program called "Life Talk Talk" among middle and high school students in D City. Methods: The educational content of the "Life Talk Talk" program was compiled through nine rounds of consultations and meetings with suicide prevention experts. Prior to the implementation of the program, consent was obtained from all research participants and their guardians. First , a pilot study was conducted with 100 middle and high school students located in D city, following which the present study was conducted from May to July 2023 with 1,400 middle and high school students in D city. The effects of the program were evaluated by assessing the changes in suicidal ideation, help-providing abilities, and suicide prevention knowledge in the data collected both before and after the education. Statistical analysis included frequency analysis and a paired-sample t-test. Results: The final analysis included 1,380 participants. In the general characteristics,, 1,079 people (78 %) answered "yes" to the question about suicide prevention education experience . The study found a significant decrease in suicidal attitudes (t=-8.92, p<.001) and significant improvements in emotional and cognitive attitudes of participants after the "Life Talk Talk" program . Additionally, all five items related to help-providing abilities (t=-23.83, p<.001) and suicide prevention knowledge (p<.001) showed significant improvement from before the program. Conclusion: The significance of this study lies in demonstrating the effectiveness of the "Life Talk Talk" suicide prevention education program in reducing suicidal attitudes as well as improving help-providing abilities and suicide prevention knowledge. Therefore, to enhance the effectiveness of suicide prevention education, it is essential to regularly implement concise and engaging educational programs that capture the attention of adolescents.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.121-129
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• 2014

As e-books have been becoming common, the market for digital textbooks also has been expected to grow rapidly. In this paper, we introduce our experience of developing interactive e-books with Unity3D, and the result of user's experiment of using the books. The e-books are targeted to the lower grades in elementary schools, and they are a series of a fairy tale story with educational information on flat tide. They support rich user interactions such as dragging and clicking objects and rich media including 3D animations, videos, pictures, and augmented reality. We separate educational information from the main story in order to meet some incompatible issues among story, education, and user interaction. We conducted user experiments with twenty four 4th grade students and 95.8% (23 from 24) of them liked the e-books. They also thought the e-books would help them study about flat tide and sea creatures in there.

• Journal of Korean Neurosurgical Society
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• v.42 no.3
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• pp.191-194
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• 2007

Objective : Homeless patients probably have epidemiologic features that are different from those of general population. However, there have been no published articles about clinical characteristics of neurosurgical homeless patients. The authors tried to assess the clinical characteristics and treatment outcome of homeless neurosurgical patients. Methods : We retrospectively reviewed the medical records and radiological films of 76 homeless patients and 72 non-homeless patients following head trauma who were admitted to our neurosurgical department between June 2001 and June 2005. We compared two groups of the patients with the demographics, the clinical and laboratory characteristics. Also, 3D-day mortality was determined according to Glasgow Coma Scale (GCS) score. Results : Age of homeless patients was younger than that of non-homeless patients. Homeless patients had previous craniotomy evidences in skull x-rays more frequently (10.5% vs. 1.4%). Acute subdural hematoma was the most common type of head injury in the two groups. Moderate and severe head injury, based on GCS score on admission was more frequent in homeless patients (64% vs. 39%). Fifty percent of homeless patients underwent operation for traumatic head injury. However, 3D-day mortality according to GCS score was not significantly higher in homeless patients. Conclusion : Most homeless neurological patients were relatively young men. Also, moderate or severe brain injuries were observed more frequently. However, mortality rate of homeless patients in neurosurgical field is not significantly higher in the present study.

• Journal of the Korean Home Economics Association
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• v.40 no.6
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• pp.69-83
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• 2002

This study examined the effects of demographic variables on buying behavior, and investigated buyers'perceived value and risk perception of the internet shopping mall. The sample was collected by a department store in Daegu, and it included 1,732 individuals using the Cyber Mall. Research methods used in this study were simple statistics, t-test and ANOVA. The buyers perceived values through the internet shopping mall were classified into five categories-price, time, convenience, intrinsic attributes, reliability and the risk perception also was classified such as the overall purchasing process, quality of products, exposure of the personal information, delivery system, refund and exchange. The major findings of this study were 1) most important categories affecting their buying behavior were the value of convenience and following values in order were time, price, reliability, intrinsic attributes. 2) the risk perception were overall purchasing behavior, quality of products, exposure of personal information, delivery, and refund & exchange in order. 3) age of buyers, buying experience on the internet shopping mall, and gender were the important factors affecting the buyers'perceived value and risk. 4) the study also, showed that according to the variety of products, buyers perceived the value and risk differently, for example, the price was the most important perceived value in case of food product. The implication of the study is to strategically suggest how to enhance the buyers'perceived value and diminish perceived risk of different products.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.5
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• pp.906-919
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• 2015

The Deep Draft Semi-Submersible (DDS) concepts are known for their favourable vertical motion performance. However, the DDS may experience critical Vortex-Induced Motion (VIM) stemming from the fluctuating forces on the columns. In order to investigate the current-induced excitation forces of VIM, an experimental study of flow characteristics around four square-section cylinders in a square configuration is presented. A number of column spacing ratios and array attack angles were considered to investigate the parametric influences. The results comprise flow patterns, drag and lift forces, as well as Strouhal numbers. It is shown that both the drag and lift forces acting on the cylinders are slightly different between the various L/D values, and the fluctuating forces peak at L/D = 4.14. The lift force of downstream cylinders reaches its maximum at around ${\alpha}=15^{\circ}$. Furthermore, the flow around circular-section-cylinder arrays is also discussed in comparison with that of square cylinders.

• Journal of Korean Academy of Nursing
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• v.16 no.2
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• pp.36-43
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• 1986

The main purpose of this study was to explore the effect of the stress of hospitalization on the sleep pattern. Additionaly, this study was also to demonstrate how Johnson's nursing model may be applied to as nursing process. 104 hospitalized patients on surgical and medical wards were asked to rate 49 stress producing events associated with experience of hospitalization and sleep pattern scale. Five university hospitals were used as the setting for this study. Data for the study were collected by patient interview during hospitalization, self-reports and review of charts. For the analysis of the data, the pearson's correlation analysis of covariance and regression analysis were used. The results of this study were stated as follows; 1. The mean of the hospital stress scores was 111.261(S.D.=26.160). This means that the level of the hospitalization stress is high. The mean of the sleep pattern scores was 12.204(S.D. =2.615) This means that the characteristic's of the sleep pattern is poor. 2. The relationship between the hospitalization stress and sleep pattern was statistically significant at .01 level. 3. The effect of the hospitalization stress influenced strongly on the sleep pattern after sex, trait anxiety as covariates controlled. 4. The hospitalization stress revealed a 12% pre-diction as an influenced factor for the sleep pattern. Therefore, It can he said that the hospital stress did contribute significantly to the characteristics of the sleep pattern. Johnson's model can he also said that it is useful for the the assessment and diagnosis in nursing process.

• Journal of Korean Port Research
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• v.14 no.4
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• pp.419-427
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• 2000

Today travel demand continues to increase with spread of economic zones. Also, urban freeway plays an important role in intra-zone transportations as a major corridor in a big city. However, most of urban freeways experience a severe congestion with the excess of inflowing or outflowing traffic through freeway ramps. The purpose of this study is to identify the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the speed predictive models on the ramp junctions of urban freeway under the intelligent transportation system(ITS) settings. From the analyses of traffic characteristics following results were obtained: ⅰ) 24 hours average traffic characteristics flow, occupancy, speed under the ITS settings showed about 40%, 38%, 8.8% increase each on urban freeway junctions period when compared with that under the non-ITS settings each other. Free flow speed and traffic flow on the mainline sections of urban freeway under the ITS settings also showed about 20% and 17% increase when compared with that under the non-ITS, respectively. ⅱ) The upstream when compared speed( $S_{u}$)and downstream occupancy( $O_{d}$) were especially shown to have higher explanatory powers on the stable flow ramp junctions, but the upstream speed( $S_{u}$) and downstream flow( $V_{d}$) were especially shown on the unstable flow ramp junctions of urban freeway under the ITS settings.ngs.ngs.