• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.8
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• pp.929-934
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• 2012

This study was carried out to analyze the dynamic characteristics of laser tailor-welded blanks (TWBs) made of dissimilar materials. The analysis was performed using Hyper Works 10.0 with Solver LS-DYNA v.971. 2D-Shell was used as the modeling element, and the number of elements and nodes was 35,641 and 36,561, respectively. The impact speed was 10 km/h. To analyze the impact characteristics according to the height of the weld line for the upper and lower parts of the center pillar, the length of the lower part was set as 300 and 400 mm. When the lower part was made of SPFC980 steel with a length of 300 mm, the deformation was the smallest and the absorbed energy of the impact force was the largest. On based the lower part of center pillar, the position of TWB shows the shorter and the better value. In other words, the performance depended on the proportion of the upper part made of high-strength SABC1470 steel. A lower part made of SPFH590 steel showed large deformation. In contrast, a lower part made of SPFC980 steel showed significantly lesser deformation. Therefore, the impact performance of a lower part made of SPFC980 steel with a length of 300 mm showed the best analysis result.

• Investigative Magnetic Resonance Imaging
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• v.11 no.1
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• pp.10-19
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• 2007

Conventional MRI methods using T1-, T2-, diffusion-, perfusion-weighting, and functional imaging rely on characterizing the physical and functional properties of the tissue. In this review, we introduce an imaging modality based on measured the mechanical properties of soft tissue, namely magnetic resonance elastography (MRE). The use of palpation to identify the stiffness of tissue remains a fundamental diagnostic tool. MRE can quantify the stiffness of the tissue thereby providing a objective means to measure the mechanical properties. To accomplish a successful clinical setting using MRE, hardware and software techniques in the area of transducer, pulse sequence, and imaging processing algorithm need to be developed. Transducer, a mechanical vibrator, is the core of MRE application to make wave propagate invivo. For this reason, considerations of the frame of human body, pressure and friction of the interface, and high magnetic field of a MRI system needs to be taken into account when designing a transducer. Given that the wave propagates through human body effectively, developing an appropriate pulse sequence is another important issue in obtaining an optimal image. In this review paper, we introduce the technical aspects needed for MRE experiments and introduce several applications of this new field.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.331-336
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• 2015

Medical electrical equipment - Part 1: General requirement for basic safety and essential performance of MFDS was revised as 3th edition and Medical electrical equipment Part 2-54: Particular requirements for the basic safety and essential performance of X-ray equipment will be expected to be announced as notification. Therefore this technical report was written to introduce provision of the particular requirements, replacement, addition, amendment. The purpose of this particular requirements is to secure requirements for basic safety and essential performance of X-ray equipment for radiography and radioscopy. X-ray high voltage generator, mechanical protective device, protection against radiation is included in this particular requirements. Medical electrical equipment - Part 1, Part 1-2, Part 1-3 is applied to this particular requirements. If the requirements is announced as notification, It is expected to widen understanding for basic safety and essential performance of X-ray equipment for radiography and radioscopy and play a part to internationalize of medical equipments.

• Journal of The Korean Association For Science Education
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• v.27 no.1
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• pp.50-58
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• 2007

In this study, students' thoughts were searched according to the types of experiments related to the "law of definite proportions" in 9th grade science textbooks. The most common four types of experiments in textbooks were selected and analyzed for this study. It was found that the experiments needed various preconceptions and complex inferring process by students. But most of the students could not catch the concept understanding desired from the experiments. They just perceived simple observation from their senses. These phenomena were common regardless of types of experiments. These means that the level of preconceptions and inferring process for the interpretation of the experimental data did not match with students' level of thoughts. The goals of the experiments in science textbooks are to increase students' inquiry ability, and to acquire science concepts by themselves from the experiment results. But if the contents of experiments are not suitable to students' understanding level, the educational effects of the performance of these experiments were not positive. Therefore, these experiments need contents revisions for students to acquire the concept related to the "law of definite proportions" by themselves.

• Journal of Korean Physical Therapy Science
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• v.14 no.1_4
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• pp.25-36
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• 2007

The results of researching on duties of physical therapist, understanding of elderly diseases and policies related with elderly welfare came out from the survey before beginning of education to physical therapists who attended National Elderly Welfare Physical Therapist Workshop during Sep. 11th to 14th, 2007. They have already understood about long-term elderly care insurance from the policy, and responded that those policies will bring more advantage to elders. On contrary, negative response had reason of low service quality. About elderly care system, there were positive answer of appropriate alternatives to support them, but also other critics had opinion of inevitable choice for living conservation. About understanding of elderly diseases, there were more comprehension of diseases as age gets higher, but most did not understand dementia and paralysis. Past experience and process of medical treatment for their disease were such arthritis, paralysis, broken bone, and dislocation of joint. Prognosis of technical training was mostly answered positively, but linking with other related disease programs were not welcomed. Most respondents thought that professional training were needed. The results of understanding diseases during senescent had high percentage of understanding as age and education was high, and it had eye upon statistics of the survey (p < 0.05) Most of those questioned responded that it is appropriate to have six working days per week and eight hours of daily work, however, present wage is not reasonable. Most of those questioned had negative response of work independence, and had an-swered that there should be certificates needed in related fields. For difficulties during work period, they had hardship instituting direction of treatment by lack of program, level of wage, and physical difficulties. Physical therapists averagely wished to have fewer than thirty patients per therapist. After the research, physical therapists who work in those facilities of elderly care systems agreed on policies, though it should not lower service quality. In addition, they were pros to have elderly care system, yet they are still inevitable option to maintain living. For work environment, the period of work was appropriate, but had different opinions for work independence and regular number of patients. Therefore, there should be more organized treatment program that also should be linked to other practical programs at this beginning point of the policy enforcement and the time that many therapists hope to work in elderly care system.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.1
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• pp.107-121
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• 2002

The purpose of this study was to identify how nurse's image was perceived by nursing college students. The subjects included were 315 students experienced clinical practice during $20{\sim}22$ weeks and 134 students not with a total of 449 nursing students in Gwangju and Chonnam. The data were collected from November 21 to December 5, 2001 by the structured questionnaires. The research tool was measured by 30 items divided into four dimensions; traditional, professional, social and personal image of nurse. Cronbach $\alpha$ for the tool of nurse's image was 0.8960. The data were analysed by SPSS 8.0 for Windows program using frequency, percentage, mean, standard deviation, t-test, ANOVA and scheffe. The results of this study were as follows; 1. In the nurse's image related to general characteristics, there were significant differences for school graduation, applicative motivation, interpersonal relationship and image forming factor. 2. In the Image forming factors, nursing college students perceived the nurse's image by visiting hospital or admission(37.9%), watching TV(25.8) and others; nurses' appearance during clinical experience(16.3). 3. The mean score for nurse's image of clinical experience group (2.76$\pm$0.28) was lower than that of non-clinical experience group(2.89$\pm$0.31) in significance (t=4.319, p=0.000). 4. In the nurse's image according to clinical experience, there were significant differences for traditional, professional, social, personal image between two groups and the lower mean scores were found in the clinical experience group in all dimensions. The ranks of dimensions were professional image(3.08), traditional image(2.76), social image(2.65), the personal image(2.59) in clinical experience group, whereas professional image(3.21), traditional image(2.93), social image(2.75), personal image(2.71) for non-clinical experience group.5. The high score items of nurse's image were 'worthwhile work(3.48)', 'always working hard(3.30)', 'profession(3.17)', 'strong responsibility toward work(3.08)', 'have a high technical skill(3.05)' in clinical experience group and 'worthwhile work(3.69)', 'always working hard(3.28)', 'clean and decent(3.22)', 'profession(3.21)', 'have a bountiful professional knowledge(3.18)' in non-clinical experience group. 6. The highest mean score for nurse's image related to the image forming factors was 86.8 by novels or literature and the second highest was 84.3 by visiting hospital or admission. And others(mean=82.1)was the most negative nurse's image by clinical experience. In conclusion, nurse's image perceived by nursing college students will be the mirror of themselves. And clinical experience will be the important opportunity to form the professional image with white uniformed nurses in future. Therefore it is important for clinical nurses to play professional roles rightly so that nursing students could form positive nurse's image.

• Journal of Digital Convergence
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• v.16 no.8
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• pp.71-79
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• 2018

This study discussed the meaning of a drone, and especially drone journalism and legal and ethical issues around that, at an introductory dimension, which is used in various social bases, but is still just an academic discussion at the beginning stage. As a methodology, content analysis was used. It seems that drone journalism has high diffusibility as a technology with high 'relative advantage', 'compatibility', 'trial ability' and 'observability' and low 'complexity' in terms of the diffusion of innovation theory. However, it will be very likely that controversies will be raised, such as safety issue due to collision and crash, a dispute over violation of privacy that may seriously infringe privacy like individual portrait rights and a controversy about the accuracy and source of information as drone filming low price and ease of use. Suggest solutions to legal and ethical issues based on existing research. Technical stability is required. Also, it is necessary to change the awareness of journalists about the drones coverage and to educate ethics, and it is necessary to establish social public opinion on issues such as privacy violation and establish system and legal measures through it. Future research is expected to carry out empirical research including journalists and public awareness surveys.

• Journal of Korean Academy of Nursing
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• v.3 no.3
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• pp.50-61
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• 1973

Despite the intensive family Planning program of the government, which has reduced the :average population growth to 2.0 percent in 1970, the continuing high fertility rates and poor family planning services in urban slum areas has been continually pointed out by various evaluation seminars. Thus, it was felt that a study of the current status of family planning in an urban slum population was needed. The aims of the study were to: (1) delineate the general characteristics of the urban slum population (2) discover the knowledge, attitudes, and practice of family planing. (3) determine what was felt to be the ideal number of children. (4) determine the status of induced abortion. A random stratified sample of 200 women was selected from a population of 3, 118 married women, 20-49 years of age, living in the Yonsei Community Health Project area and registered at the Yonhee Community Health Service Institute. The respondents were interviewed by the investigates, using a pretested questionary, from the period of October 1 to October 30, 1972. The findings of the Study were as follows: 1. Afore than half of the respondents were in the high fertility age group (25-34): of lower educational level (under primary School) : from rural areas: and with unstable sources of income. 2. The average respondent had 3.6 living children. 3. Most of the respondents had knowledge of contraceptive methods such as the Loop(78, 5%) and Oral pill (87.0%). 4. Seventy seven percent of the respondents recognized the Health Center as an available source for family planning. 5. About seventy percent of the respondents approved of family planning. 6. Eighty four point five percent of all the respondents answered that using contraceptives is harmful to maternal health. 7. Currently, 21.0 percent of the respondents were using contraceptives, while 40.0 percent of the respondents were current users or had used contraceptives. 5. Of the respondents who had ever stopped using contraceptives, 78.0 percent gave side effects as the reason they discontinued the method. 9. The average number of ideal children reported by the respondents was 3.5. 10. If they had only 2 daughters, 85.5 Percent of the respondents thought they must have more children. 11. Sixty nine point five percent of the respondents approved of induced abortion for unwanted pregnancies, while 34.5 percent of the respondents had experienced induced abortion for unwanted pregnancies. The mean number of induced abortion for unwanted pregnancies was 0.7. 12. The result of this study showed that such urban slum population would be one of the most important target of the family planning services, therefore further social-psychological researches with technical development on this area are recommended.

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.118-128
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• 2015

Recently BIM technology has been expanded for using in construction project. Due to the high-cost of BIM infrastructure development, lack of regulations, lack of process and so forth, usage of BIM has been delayed than initial expectations. In design phase, especially, collaboration based on BIM system has been a key factor for successful next generation building project. Through the analysis of current research trends about IT technologies, virtualization and BIM service, data exchange such as drawings, 3D model, object data, properties using cloud computing and virtual server system is defined as a most successful solution. The purpose of this study is to enable the cloud computing BIM server to provide several main functions such as editing models, 3D model viewing and checking, mark-up and snapshot in high-performance quality by proper design of VDI system. Concurrent client connection performance is a main technical index of VDI. Through testing of test-bed server client, developed VDI system's multi-connect control is evaluated. Performance-test result of BIM server VDI effect to development direction of cloud computing BIM service for commercialization.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.4
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• pp.423-428
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• 2016

The last stage blades of a low pressure (LP) turbine get frequently fractured because of stress corrosion cracking. This is because they operate in a severe corrosive environment that is caused by the impurities dissolved in condensed steam and high stress due to high speed rotation. To improve the reliability of the blades under severe conditions, 12% Cr martensitic stainless steel, having excellent corrosion resistance and higher strength, is widely used as the blade material. This paper shows the result of root cause analysis on a blade which got fractured suddenly during normal operation. Testing of mechanical properties and microstructure examination were performed on the fractured blade and on a blade in sound condition. The results of testing of mechanical properties of the fractured blade showed that the hardness were higher but impact energy were lower, and were not meeting the criteria as per the material certificate specification. This result showed that the fractured blade became embrittled. The branch-type crack was found to have propagated through the grain boundary and components of chloride and sulfur were detected on the fractured surface. Based on these results, the root cause of fracture was confirmed to be stress corrosion cracking.