• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1184-1191
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• 2016

This paper introduces the development of a transient monitoring system to detect the early stage of a transient, to identify the type of the transient scenario, and to inform an operator with the remaining time to turbine trip when there is no operator's relevant control. This study focused on the transients originating from a secondary system in nuclear power plants (NPPs), because the secondary system was recognized to be a more dominant factor to make unplanned turbine-generator trips which can ultimately result in reactor trips. In order to make the proposed methodology practical forward, all the transient scenarios registered in a simulator of a 1,000 MWe pressurized water reactor were archived in the transient pattern database. The transient patterns show plant behavior until turbine-generator trip when there is no operator's intervention. Meanwhile, the operating data periodically captured from a plant computer is compared with an individual transient pattern in the database and a highly matched section among the transient patterns enables isolation of the type of transient and prediction of the expected remaining time to trip. The transient pattern database consists of hundreds of variables, so it is difficult to speedily compare patterns and to draw a conclusion in a timely manner. The transient pattern database and the operating data are, therefore, converted into a smaller dimension using the principal component analysis (PCA). This paper describes the process of constructing the transient pattern database, dealing with principal components, and optimizing similarity measures.

• Korea Journal of Hospital Management
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• v.15 no.3
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• pp.17-32
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• 2010

The purpose of this study is to analyze the influence of DISC behavior pattern, stress-managing method, and the stress level on job attitude of hospital Employees, and to provide suggestions for effective human resources management in hospital settings. First, the research suggested emotional or aversive stress-managing method had significant influence to the stress level, whereas DISC behavior patterns did not. Second, to the job satisfaction, Influence, Compliance and Steadiness of DISC behavior patterns, challenging or aversive stress-managing method, and the stress level showed immediate meaningful effect. Third, for the system immersion, challenging or emotional ress-managing method as well as the job satisfaction showed direct influence. Especially, the challenging method had not only a direct but an indirect effect through mediating job satisfaction.

• Structural Engineering and Mechanics
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• v.69 no.2
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• pp.221-230
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• 2019

In this paper, shear behavior of non-persistent joint surrounded in concrete and gypsum layers has been investigated using experimental test and numerical simulation. Two types of mixture were prepared for this study. The first type consists of water and gypsum that were mixed with a ratio of water/gypsum of 0.6. The second type of mixture, water, sand and cement were mixed with a ratio of 27%, 33% and 40% by weight. Shear behavior of a non-persistent joint embedded in these specimens is studied. Physical models consisting of two edge concrete layers with dimensions of 160 mm by 130 mm by 60 mm and one internal gypsum layer with the dimension of 16 mm by 13 mm by 6 mm were made. Two horizontal edge joints were embedded in concrete beams and one angled joint was created in gypsum layer. Several analyses with joints with angles of $0^{\circ}$, $30^{\circ}$, and $60^{\circ}$ degree were conducted. The central fault places in 3 different positions. Along the edge joints, 1.5 cm vertically far from the edge joint face and 3 cm vertically far from the edge joint face. All samples were tested in compression using a universal loading machine and the shear load was induced because of the specimen geometry. Concurrent with the experiments, the extended finite element method (XFEM) was employed to analyze the fracture processes occurring in a non-persistent joint embedded in concrete and gypsum layers using Abaqus, a finite element software platform. The failure pattern of non-persistent cracks (faults) was found to be affected mostly by the central crack and its configuration and the shear strength was found to be related to the failure pattern. Comparison between experimental and corresponding numerical results showed a great agreement. XFEM was found as a capable tool for investigating the fracturing mechanism of rock specimens with non-persistent joint.

• Women's Health Nursing
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• v.25 no.4
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• pp.423-433
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• 2019

Purpose: The study aimed to examine the effects of sleep pattern, stress, and attitude towards menstruation, and behavior that causes a reduction in exposure to endocrine disrupting chemicals (EDCs) in the course of premenstrual syndrome (PMS) in female adolescents. Method: In total, 200 girls attending middle school in K city were recruited via convenience sampling between December 11 and 31, 2018, and 192 subjects were selected for the analysis. Data were analyzed using descriptive statistics, an independent t-test, ANOVA, Pearson's correlation coefficient, and multiple regression. Results: Overall, 9 (4.7%), 152 (79.2%), and 31 (16.1%) students had morning-, intermediate-, and evening-type sleep pattern, respectively. The mean scores for school-related stress were highest. Scores for stress regarding relationships with friends were the lowest. The mean score for attitudes toward menstruation was 72.33 out of 147. The mean score for behavior that led to a reduction in EDCs exposure was 56.57 out of 85. The mean scores for PMS severity were 25.30 and 38.39 out of 60. Analysis of factors affecting PMS revealed that severity of menstrual pain (β=.28), use of analgesics during menstruation (β=.17), family history of PMS (β=-.16), stress (β=.19), and behavior that reduces EDCs exposure (β=-.17) exerted significant effects on PMS. The explanatory power of these variables was 37%. Conclusion: The findings propose the necessity of a health intervention program including educational information, which can reduce PMS in adolescents, induce the behaviors which can decrease exposure to EDCs, and activities for managing the stress levels.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.2
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• pp.59-64
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• 2014

In this study, the large scale test was performed to investigate the behavior of failure for the embankment and spillway transitional zone by overtopping. The pore water pressure, earth pressure, settlement and failure pattern of covering embankment with geotextile were compared and analyzed. The pore water pressure showed a small change in the spillway transition zone and core, indicating that the geotextile efficiently reinforced the embankment. The earth pressure decreased the infiltration of the pore water only in inclined cores type to secure local stability. The behavior of failure started from the bottom and gradually progressed upwards. After the intermediate overtopping period (100 min), width and depth of the seepage erosion were very small due to the effect of geotextile which delayed failure. Therefore, the reinforced method by geotxtile was a very effective method to respond to the emergency due to overtopping.

• Journal of Environmental Science International
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• v.30 no.1
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• pp.1-10
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• 2021

The purpose of this study is to verify the physiological and psychological benefits of indoor garden to humans and to analyze the comparison according to Type A behavior pattern. The subjects included 18 male university students. Heart rate variation was used as a parameter of physiological assessment, and Semantic Differential (SD), Profile of Mood States-Brief (POMS), and State-Trait Anxiety Inventory (STAI) were used as tools for psychological evaluation. The participants were subjected to a psychological evaluation when they were present in a garden. As a result, the parasympathetic nervous activity was increased in the indoor garden. In the analysis of psychological evaluation, indoor garden improved the positive mood states and decreased negative feelings with significant changes only in Type A group. This study supported that indoor garden can have physiological and psychological relaxing effects, which could be more significant in Type A group than Type B.

• Korean Journal of Community Nutrition
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• v.7 no.4
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• pp.495-505
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• 2002

A study was performed to develop as a screening tool the Simple Evaluation Questionnaire for Screening the Over-weight-type Dietary Pattern in 30 to 49 Year Old Adults. We used the data from the 30 to 49 year old subjects who participated in the three surveys - the health behavior survey, the dietary habit survey and the food intake survey - as the National Health and Nutrition Survey 1998. The 3,598 adults were classified into to two body fatness groups of normal (including underweight) and overweight (including obese) on the basis of their relative body weight (RBW) When comparing variables between the two groups, significant differences were found in gender, education, job, employment status, perceived health status, sadness / depression state, stress level, age, number of diseases, age when overweightedness started, maximum body weight, sleep length, drinking pattern (yes/no) , amount of alcoholic drinks, frequency of intoxication or drunkeness, amount of alcoholic drinks when drunk, intensity of exercise, frequency of exercise, exercise duration, skipped meals, small meals and drug supplements. In terms of food intake, there were significant differences in the daily food intake in terms of breakfast, dinner, daily kimchi and dairy products. In terms of mealtimes, we found differences in the amount of cooked rice at breakfast, kimchi at lunch, soup / kuk at dinner, fresh vegetables for snacks, fried foods for snacks between breakfast and lunch, and fruits /juices for snacks between lunch and dinner. After developing questions with indicators and analyzing the indicators by logistic regression analysis three times, we chose 10 questions for a simple evaluation of dietary patterns for the overweight-type category in order to give one point each. Among them we selected two questions to add one additional point and one question to add two additional points. The average scores of the overweight and normal groups, as shown by the developed questionnaire, were $5.97 \pm 2.36 \pm 7.36 \pm 2.21$, respectively. A score of seven points was selected as the cut-off point. We examined the sensitivity, specificity and positive predictive value of the questionnaire to the results of 67%, 59% and 62%, respectively.

• Nuclear Engineering and Technology
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• v.47 no.4
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• pp.454-460
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• 2015

Acoustic emission (AE) is one of the promising methods for detecting the formation of stress corrosion cracks (SCCs) in laboratory tests. This method has the advantage of online inspection. Some studies have been conducted to investigate the characteristics of AE parameters during SCC propagation. However, it is difficult to classify the distinct features of SCC behavior. Because the previous studies were performed on slow strain rate test or compact tension specimens, it is difficult to make certain correlations between AE signals and actual SCC behavior in real tube-type specimens. In this study, the specimen was a AISI 304 stainless steel tube widely applied in the nuclear industry, and an accelerated test was conducted at high temperature and pressure with a corrosive environmental condition. The study result indicated that intense AE signals were mainly detected in the elastic deformation region, and a good correlation was observed between AE activity and crack growth. By contrast, the behavior of accumulated counts was divided into four regions. According to the waveform analysis, a specific waveform pattern was observed during SCC development. It is suggested that AE can be used to detect and monitor SCC initiation and propagation in actual tubes.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.5 s.108
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• pp.1-10
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• 2004

The geometry of headboxes is of great importance in obtaining good formation, even basis weight profile and fiber orientation. Therefore, many attentions have been made to examine the influence of the geometry of headboxes on the flow behavior. In this study, to evaluate flow behavior in headboxes, three types of turbulence generators were examined using pilot headbox. Velocity profiles in MD and CD were measured using a pressure monitoring system and flow in headboxes was visualized by dye injection method. CD velocity profiles at three different locations inside the slice of Type A headbox showed that the velocity increased downstream to slice exit and had a pattern with four humps due to the persisting wall effect of step diffusors. Results from the evaluation of normalized velocity profile and flow visualization showed that L-shaped Type C headbox caused a large pressure drop but it lacked in flow stabilizing ability.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.5
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• pp.636-646
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• 2013

Purpose: This study was done to provide data that would contribute to effective task performance in clinical nursing and development of nursing professional by understanding job stress, job satisfaction and organizational commitment according to Life Organization (LIFO) behavior types of novice nurses. Methods: This study was a cross-sectional survey and the participants were 313 novice nurses who worked in one university hospital located in the city of Gwangju. Data were collected through the structured questionnaires that included general characteristics, job stress, job satisfaction, and organizational commitment scales. Collected data were analyzed using descriptive statistics, and ANOVA with SPSS/WIN 19.0. Results: Regarding job stress according to LIFO behavior types of novice nurses, there were statistically significant differences between the favorable situation and the unfavorable situation. There were also statistically significant differences regarding the organizational commitment according to LIFO behavior types. Conclusion: The results indicate a difference in behavior patterns of novice nurses that suggest a need for education in order to reduce stress from the job and enhance organizational commitment by developing each nurse's preferred pattern and compensating for unfavorable patterns, as well. There also needs to be nursing resources that take into consideration behavior patterns of novice nurses.