• Journal of computational fluids engineering
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• v.21 no.3
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• pp.55-63
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• 2016

Nowadays, large container ships are continually developed and that's why the bow and stern structural stability problems by slamming become a significant more and more. However, due to the complexity of slamming, it is difficult to consider those problems at the design stage. For this reason, we attempt numerical analysis through SNUFOAM by generating the bow and stern two-dimensional cross-sectional grid in WILS JIP experiment at KRISO. Unlike the conventional method for the computation time saving, by setting the inlet flow conditions referred to the model test, we analyzed the slamming without applying the grid deformation method. As a result, when the stern model, as in the previous studies, it was possible to obtain quantitatively the fluid impulse is close to the experimental results. When the bow model, we can found the change by the position of force sensors which are derived for the bulbous bow and obtained fluid impulse and flow shape at slamming similar to the model test.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.819-824
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• 2000

The flow inside an axial turbomachinery must be unsteady. Rotor-stator interaction by two blade rows influences performance, the generation of noise and vibration. So, it will be necessary to study the rotor-stator interaction for the design of an axial fan in which the axial gap between two blade rows is small. In this study, rotor-stator interaction is investigated by experimental methods. The research fan has one stage which consists of 24 rotor blades and 22 stator blades. Three-dimensional velocities measured using $45^{\circ}$ slanted hot wire probe and total pressure is measured using Kiel total pressure probe between rotor and stator with the axial 25%, 55%, 145% of chord length,. This study describes the influence of rotor-stator gap on the flow pattern, performance and loss. The efficiency curve show that the change of the rotor-stator gap make difference in the efficiency. And, the 3-dimensional velocity distribution show that the potential interaction between the rotor and the stator have a great effect on the flow field downstream of rotor, where there are wake flow. various vortices in hub region and leakage vortex in casing region etc.

• Earthquakes and Structures
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• v.7 no.5
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• pp.647-665
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• 2014

Squat reinforced concrete walls require enough shear strength in order to promote flexural yielding, which creates the need for designers of an accurate method for strength prediction. In many cases, especially for existing buildings, strength estimates might be insufficient when more accurate analyses are needed, such as pushover analysis. In this case, estimates of load versus displacement are required for building modeling. A model is developed that predicts the shear load versus shear deformation of squat reinforced concrete walls by means of a panel formulation. In order to provide a simple, design-oriented tool, the formulation considers the wall as a single element, which presents an average strain and stress field for the entire wall. Simple material constitutive laws for concrete and steel are used. The developed models can be divided into two categories: (i) rotating-angle and (ii) fixed-angle models. In the first case, the principal stress/strain direction rotates for each drift increment. This situation is addressed by prescribing the average normal strain of the panel. The formation of a crack, which can be interpreted as a fixed principal strain direction is imposed on the second formulation via calibration of the principal stress/strain direction obtained from the rotating-angle model at a cracking stage. Two alternatives are selected for the cracking point: fcr and 0.5fcr (post-peak). In terms of shear capacity, the model results are compared with an experimental database indicating that the fixed-angle models yield good results. The overall response (load-displacement) is also reasonable well predicted for specimens with diagonal compression failure.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.81-93
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• 2001

The purpose of this study was to develop a continuing nursing care program for cancer patients and the caregivers staying at their home and to test its effects on patients' symptom distress, caregiver burden, and satisfaction of life. The continuing nursing care program was based on the homecare needs of cancer patients, and was provided by three clinical nurses who took care of the patients while they were hospitalized. The program consisted of discharge education about selfcare using education materials(book and handout) and provisions of direct care. These were counselling and education during which visiting patients' home one week after discharge and telephone counseling two weeks after discharge. Counseling by telephone was always available during the research period. A quasi-experimental research design was used to test the effects of the program. Subjects for this study were 53 cancer patients discharged from the hospital and caregivers. These subjects were assigned to an experimental group (n=23) receiving continuous nursing care, or to a control group (n=30) not receiving continuous nursing care. Data from control group was collected first to protect from contamination. Data collection was done from October of 1998 to February of 2000. The collected data was analysed using mean, t-test, and chi-square test computed by SPSS software. The summary of results was as follows: 1) The symptom distress was a little decreased at posttest, but there were no significant differences between the experimental and the control group in symptom distress. 2) The score of caregiver burden was significantly decreased in experimental group at posttest, but no differences in control group. 3) There were no significant differences between the experimental and control group in the satisfaction of life. 4) The score of satisfaction of continuing nursing care program in experimental group at posttest was 2.321 of 3. In conclusion, even though this study did not obtain evidence of effectiveness of continuing nursing care program on patients, such as. It is still expected to be effective by a more improved program. Therefore we want to give some suggestions for further studies. 1) It is needed to make a communication channel with the patient's doctor to response promptly and appropriately to patient's conditions. 2) The research is necessary on patients in terminal stage or early stage of cancer diagnosis who have many nursing needs. 3) It is needed to readjust the roles and job assignment of clinical nurse to implement effectively as a program provider.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.222-227
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• 2001

Full scale construction tests of CFT(concrete filled steel tube) column to solve construction problem and to confirm quality were performed in apartment site. To improve construction efficiency, the tests has been accomplished two stages after the tests for material mixing design had been completed. In the first stage, the experimental variables were the placing methods, existence of guiding pipe, placing velocity and drop height and the height of specimen were $3.6{\cal}m$. In the second stage, Filling steel tube of 9.6m height with concrete was performed by two ways, that is, the pump-up method and the dropping method. The filled condition of the concrete and concrete strength distribution according to the column height were checked and the quality of the CFT column was confirmed.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.8
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• pp.477-486
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• 2000

This paper presents Pspice modeling methods for spark gaps and ZnO varistors and describes the application for the two-stage surge suppression circuit which was composed of the nonlinear components. The simulation modelings of nonlinear components were conducted on the basis of the voltage and current curves measured by the impulse current with the time-to-crest of $1~50 \mus$ and the impulse voltage with the rate of the time-to-crest of 10, 100 and 1000 V/\mus$. The firing voltages of the spark gap increased with increasing the rate of the time-to-crest of impulse voltage and the measured data were in good agreement with the simulated data. The I-V curves of the ZnO varistor were measured by applying the impulse currents of which time-to-crests range from 1 to $50 \mus$ and peak amplitudes from 10 A to 2 kA. The simulation modeling was based on the I-V curves replotted by taking away the inductive effects of the test circuit and leads. The meximum difference between the measured and calculated data was of the order of 3%. Also the two-stage surge suppression circuit made of the spark gap and the ZnO varistor was investigated with the impulse voltage of $10/1000\mus$$mutextrm{s}$ wave shape. The overall agreement between the theoretical and experimental results seems to be acceptable. As a consequence, it was known that the proposed simulation techniques could effectively be used to design the surge suppression circuits combined with nonlinear components.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.2
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• pp.277-288
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• 1998

The study was conducted to provide basic data for the development of nursing management research and suggesting the direction of the future research and the theory of nursing management. In this study, 456 pieces of articles that had been published for the last 10 years from 1987 to 1996 were analyzed based on the nursing research methodology of Lee et al. (1991). The results were as follows: 1. The whole articles were divided into two groups. that is. degree dissertations of 69.7%(307 pieces of master's and 11 pieces of doctor's) and non-degree papers of 30.3%. 2. In the light of graduate school types. the papers of the graduate school of administration formed 41.8% of the entire articles and those of the general graduate schools formed 32.4% of them. 3. In the methodology of research design. survey research held 86.8% of the whole articles. 4. In the research subject. nurses held 68.4%. others 14.6%. patients 9.4%. 5. In the data collecting method. questionnaire held 85.1%. 6. In the statistics method. 88.1% of the entire articles used inference method. 7. In the area of nursing management. direct stage formed 26.8%. control stage 21.9%. and staffing stage 20.6% of the whole articles. 8. In the light of frequency of the key concept. job satisfaction held 10.9%. nursing task 8.5%. role 7.0%. stress 4.7%, and perception 4.0%. On the basis of the results. the following suggestions were made: 1. Qualitative studies should be done to recognize the phenomena. and experimental studies to prove the intervention for the improvement of future nursing management researches. 2. For the development of nursing management. all-inclusive studies. the group or the whole organization-centered studies rather than nurse-centered, should be required. 3. In order to be valid. data should be collected by various methods. 4. For the balanced studies of nursing management. getting out of the concentrated study of just one concept, repetitive study of various concept should become the subject of them.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.3
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• pp.369-375
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• 1999

Objective: To evaluate the effect of serum obtained before and after treatment for endometriosis on in vitro fertilization and development of two cell mouse embryo. Design: Pretreatment and posttreatment comparoson of fertilization of mouse oocyte and embryo development in serum supplement from patients with endometriosis; result were compared using Stuent T-test analysis. Method: Infertility Clinic, Department of Obstetrics and Gynecology, Collage of Medicine, Won kwang university, Korea. Patients was chosed eleven consecutive women with endometriosis. Interventions was all patient underwent laparoscopic or conservative surgery. This was followed by a 6-month course of burserelin acetate $900{\mu}g/d$. Main outcome was measured total number of fertilization and embryo that was fertilization after 24 hours and reached blastocyst stage after 72 hours of incubation were compared before and after treatment. Result: Before treatment, 47% of the oocyte were fertilized and 31% of the embryo reached blastocyst stage. After treatment, Significantly more fertilized and Significantly more embryo developed to blastocyst on the stage I and II of endometriosis. Conclusion: The fertilization and embryo toxicity of serum samples from patients with endometriosis is lost after treatment.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.320-329
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• 1999

This study has been done for the purpose of testing the effect of Health promotion Education on the Health perception and Health behavior performance of Elementary school student's. The collection data has conducted from June 19, 1999 to August 24, 1999. The subjects for this study were sixth grade of 'ㅅ' elementary school. which is located in 'ㄱ' city a chosen one class experimental group(38) and as a control group(38). The study were designed as nonequivalent control group pretest. posttest. follow test design. In pretest, the general characteristics of two groups, health perception and Health performance were measured, the Experimental group was given health promotion Education for a one week after the posttest, and follow test was done Health performance. for eight week's summer vocation. The instrument used for this study were Health perception scale developed by Ware(l979) were modified by Lee(l984) and Health promoting behavior scale developed by Kim(l997) were modified by No Tae Su(l999). The data analysis was done using t-test, $x^2$ -test, ANOVA. and pearson correlation coefficient using SAS/PC program. The result of this study are summarized as follows: l) There is on difference between experimental group and control group 2) The hypothesis is factor's are supported 'The experimental group which was given health promotion education will shows higher health perception and health behavior performance than control group which given that' (meal habit F=6.40 P<.05. mental health F=8.02 P<.01) 3) In health behavior performance, scale the highest domain was mental health, personal hygiene, meal habit Exercise. The following suggestions are made based on the above results: 1) Replication of the research is needed to confirm effects of health perception and Health promotion education including the elementary school students. 2) Elementary school teachers should make an effort to develop of Health perception progress and carry about continue Health promotion education program for profit stage of growth and development for elementary school students.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.4
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• pp.301-306
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• 2016

During the initial stage of propulsion shaft design, the shaft alignment process includes a thorough consideration of lateral vibration to verify the operational safety of the shaft. However, a theoretical method for analyzing forced lateral vibrations has not been clearly established. The methods currently used in classification societies and international standards can only ensure a sufficient margin to avoid the blade-passing frequency resonance speed outside the range of ${\pm}20%$ of the maximum continuous rating (MCR) for the engine. Typically, in shaft alignment analyses, longer center distances between the support bearings promote affirmative results, but the blade order resonance speed can approach the lower limit for lateral vibration. Therefore, this matter requires careful attention by engineers, and a verification of the theoretical analysis by experimental measurements is highly desirable. In this study, both theoretical and experimental analyses were conducted using strain gauges under two draught conditions of vessels used as 50,000-DWT oil/chemical tankers, introduced recently as eco-friendly ships. Based on the analyses, the influence of the lateral vibration on the shafting system and the system's reliability was reviewed.