• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 추계학술대회 논문집
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• pp.254-259
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• 2003

The 4-probe method with a voltage tap on terminals has been used for the measurement of the critical current of multi-strand high-Tc superconducting (HTS) cables. And the critical current of cables is obtained as the measured total current divided by the number of conductor when the terminal voltage exceeds the predetermined criterion of critical current. However, because of the non-uniform current distribution due to the different critical current, shapes, and other characteristics of each conductor this is not applicable method to the multi-strand HTS cable. To determine the critical current of multi-strand HTS cable the critical current of each conductor must be measured with different method. In this paper, the current distribution and the critical current of each conductor in multi-strand cable were measured with specially made pick-up coils and voltage taps. It is presented that the real critical current of multi-strand is smaller than sum of each conductors. The main cause of non-uniform current distribution is the different resistances appeared in each HTS wires.

• 간호행정학회지
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• 제10권3호
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• pp.345-364
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• 2004

Purpose: This is develop a critical pathway as an useful alternative to the previous management system in order to restriction of medical resources, high expectation of ordinary people to health and application for DRG. Method: In order to preliminary critical pathway, we analyzed 30 cases of medical records of patients who had lobectomy and pneumonectomy at the Yonsei Medical Center in Seoul. An expert validity test was taken for the preliminary critical pathway, and clinical validity test was also done. After these processes, the final critical pathway was developed. Result: Among 10 cases, one was excluded in this study due to the complication after operation. 7 of total 9 patients were discharged earlier than the expected day, 1 patient was just discharged at the expected day, and 1 patient was discharged 4 days later than the expected day at the 12th day after operation. Conclusion: The critical pathway is developed without difficulty because the posoperative management for patients with lobectomy and pneumonectomy is uncomplicated. Therefore, if it is more researched on the clinical application, then the activity of C.Q.I. will be able to sustain the patient oriented management system.

• 한국전기전자재료학회논문지
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• 제16권5호
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• pp.418-423
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• 2003

AC loss is an important issue in the design of high-T$\sub$c/ superconducting power cables which consist of a number of Bi-2223 tapes wound on a former. In the cables, the tapes have different critical currents intrinsically. And they are electrically connected to each other and current leads. These make loss measurements considerably complex, especially for short samples of laboratory size. So special cautions are required in the positioning of voltage leads for measuring the true loss voltage. In this work we have prepared a conductor composed of three Bi-2223 tapes with different critical currents. The critical current and AC loss characteristics in the conductor have experimentally investigated. The results show that for uniform current distributions the conductor's critical current is proportional to the critical current of the Bi-2223 tape to which a voltage lead is attached. However it depends on the current non-uniformity parameter in the conductor rather than the tape's critical currents for nonuniform current distributions. The loss tests indicate that the AC loss is dependent on arrangements of voltage leads but not on their contact positions. The measured losses in the conductor also agree well with the sum of the transport losses measured in each Bi-2223 tape.

• 한국철도학회논문집
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• 제10권3호
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• pp.257-263
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• 2007

The critical speed above which the vehicle become unstable is one of the items that should be verified in the development of a new train. In the case of a high speed tilting train, which requires both higher critical speed and higher curving speed, the critical speed should be more carefully treated because the both requirements are in conflict with each other in the conventional train design. The main purpose of the present work is to estimate the linear and non-linear critical speeds of 200km/h Korean Tilting Train 'Hanbit200' under development. The newly developed self-steering mechanism was attached to the tilting train to ensure that the critical speed falls under the lower yaw stiffness which is needed to secure higher curving performance. The simulation for predicting the critical speed was done by a commercially available vehicle dynamics software. A full scale roller rig test was carried out to validate the numerical results and to verify the effectiveness of the self-steering mechanism.

• 통합자연과학논문집
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• 제12권2호
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• pp.58-68
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• 2019

Critical thinking is essential to implementing the nursing process requiring timely decision making. The study examined the effects of a critical thinking course for nurses in the RN-BSN program. The study used a pre- and post-test design with a control group. The experimental group was a convenience sample of 24 working nurses attending a health college. The control group was 24 fellow nurses. The nursing process-based critical thinking course was provided to the experimental group two and half hours a week for 8 weeks. Teaching methods included lectures followed by a summary and quiz, brainstorming and action learning, and lecturer feedback. A pamphlet about views of professional occupation was provided to the control group. The data were collected using self-report questionnaires and analyzed to examine differences in the test scores before and after the intervention. The scores of critical thinking disposition, problem-solving process, and clinical competence increased significantly in the experimental group but did not in the control group. The difference between the two groups was also statistically significant in critical thinking disposition, problem-solving process, and clinical competence. It is necessary that a robust educational program or training to enhance critical thinking ability of nurses are provided in clinical settings and that nurses keep going on thinking critically in their practice.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.310-316
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• 2019

Fluidelastic instability is a key issue in steam generator tube bundles subjected in cross-flow. With a low flow velocity, a large amplitude vibration of the tube observed by many researchers. However, the mechanism of this vibration is seldom analyzed. In this paper, the mechanism of cross-flow effects on fluidelastic instability of tube bundles was investigated. Analysis reveals that when the system reaches the critical state, there would be two forms, with two critical velocities, and thus two expressions for the critical velocities were obtained. Fluidelastic instability experiment and numerical analysis were conducted to obtain the critical velocity. And, if system damping is small, with increases of the flow velocity, the stability behavior of tube array changes. At a certain flow velocity, the stability of tube array reaches the first critical state, a dynamic bifurcation occurs. The tube array returns to a stable state with continues to increase the flow velocity. At another certain flow velocity, the stability of tube array reaches the second critical state, another dynamic bifurcation occurs. However, if system damping is big, there is only one critical state with increases the flow velocity. Compared the results of experiments to numerical analysis, it shows a good agreement.

• 대한치과기공학회지
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• 제44권3호
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• pp.81-88
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• 2022

Purpose: This study was conducted to verify the effects of self-esteem and critical thinking disposition on dental laboratory technology students' field practice stress. Methods: The subjects of the study were 198 dental laboratory technology students with clinical practice experience located in Gyeongsangbuk-do and Gyeongsangnam-do. The collected data were analyzed by t-test, ANOVA, correlation analysis, and linear regression analysis using IBM SPSS Statistics ver. 22.0 (IBM). Results: The average self-esteem, critical thinking disposition, and field practice stress scores were 3.76, 3.50, and 2.40, respectively. There was a significant correlation between self-esteem, critical thinking disposition, and field practice stress. It was found that the higher the self-esteem, the lower was the field practice stress. On the contrary, among the sub-items of critical thinking disposition, when intellectual fairness increased, the field practice stress decreased; however, when healthy skepticism increased, the field practice stress increased. Conclusion: Self-esteem and critical thinking disposition were both found to have a substantial effect on field practice stress. Therefore, various educational programs need to increase self-esteem and cultivate critical thinking skills for a successful field practice and field practice stress relief of laboratory technology students.

• 간호행정학회지
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• 제6권2호
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• pp.211-225
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• 2000

With the drastically changing healthcare market, the adoption of DRG system and the use of Critical Pathway will be increased gradually in order to care hospitalized patients qualitatively and manage cost-effectively in Korea. The purpose of this quasi-experimental research is to apply and analyze the developed critical pathway to the patients with Cesarean section. 35 eligible subjects for the control group were chosen from postpartum patients who has delivered at H-hospital in Kwang-ju, and were questioned after appling previous care plan from May to December, 1998. For the experimental group, 37 subjects were chosen and questioned after applying Critical Pathway service from January to June, 1999. The instruments are a critical pathway for the patients with Cesarean section developed by chung(1998) and a questionnaire that evaluate patients and family members' satisfaction level. Also, educational materials were used to inform them in the process of Critical Pathway application. As a result of chi-square test on general characteristics, there is significant difference between control group and experimental group only in terms of room size(p= .010). There are no significant differences in the average length of stay in the hospital between control group and experimental group(t=.078). Also, the average medical consult fee has no difference significantly between two groups(t= .105). The findings showed that the experimental group with critical pathway service scored significantly higher than control group on the satisfaction level toward care services(p=.000). The items are post-operative care, postpartum exercise technique, breast feeding and breast manage through educational materials. In conclusion, the research indicates that the application of planned Critical Pathway can have a positive impact on satisfaction level of inpatients with Cesarian section.

• 간호행정학회지
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• 제8권1호
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• pp.85-95
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• 2002

The purpose of this study was to develope a critical pathway for the chemotherapy of non-small cell lung cancer patients and to identify its effects after implementation. Critical pathway was developed through 5 steps including content and clinical validity tests with collaborative efforts of nurses, clinicians, and other allied healthcare professionals with the aim of improving the quality of patient care, while minimizing cost to the patients. This paper was described an evaluation of the impact of a developed critical pathway on complication rate, length of stay, costs, the interval of treatment and patient satisfaction by nonequivalent control group posttest-only non-synchronized research design.Results were compared between the two groups of patients. There were no significant differences in demographic variables and the occurrence of bone marrow suppression between experimental group and control group(t=-0.01, p=0.992). There were statistically significant decreases in the average length of stay(t=-10.45, p=0.000), in the average cost(t=-2.988, p=0.004), and in the interval of treatment(t=-6.75, p=0.000) after implementation of the critical pathway compared to control group. Also, there was a statistically significant improvement of the patient satisfaction after implementation of the critical pathway compared to control group(t=4.57, p=0.000). This paper concludes that critical pathway in chemotherapy for lung cancer, implemented in the context of an general hospital, is the useful tool to shorten the hospital stay, reduce treatment costs, and improve the quality of life in cancer patients. Further study needs to be conducted to identify other clinical outcomes including job satisfaction, collaboration among health professionals and potential for use in education. Also, it is recommended that nurses should revise continuously the developed critical pathway through clinical implementation and maintain their role of patient advocacy through monitoring pathway compliance.

• Tuberculosis and Respiratory Diseases
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• 제63권4호
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• pp.368-371
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• 2007

Pulmonary cavities are caused by bacterial pneumonia, fungal diseases, lung cancer, and tuberculosis (TB). However, in Korea, patients with cavitary lung lesions are generally considered to have pulmonary TB, where the incidence of TB is approximately 70/100,000 per year. We report a case of chronic necrotizing pulmonary aspergillosis that was obscured by multidrug-resistant pulmonary TB.