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Professional Self-Concept, Critical Thinking Disposition and Clinical Competence in Nursing Students (간호대학생의 전문직 자아개념, 비판적 사고성향과 임상수행능력에 관한 연구)

  • Shin, Kyung-Ah;Cho, Bok-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.19 no.1
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    • pp.46-56
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    • 2012
  • Purpose: The purpose of this study was to identify the relationships among professional self-concept, critical thinking disposition and clinical competence in nursing students. Method: The participants in the study were 505 nursing students, 262 associate degree nursing students and 243 baccalaureate nursing students, all in schools in Gwangju or South Jeonla Province. A questionnaire survey was conducted from April 25 to May 27, 2011. Statistical processing was performed with SPSS 18.0 Version and the data were analyzed using t-test, ANOVA, Scheff$\acute{e}$ test, Pearson correlation coefficients, and multiple stepwise regression. Results: There was a positive correlation among clinical competence and professional self-concept, critical thinking disposition. The most effective factor for clinical competence was professional practice in professional self-concept, followed by prudence and objectivity in critical thinking disposition. The total explanation of clinical competence was 46.2%. Conclusion: The results of this study indicate confirm that professional self-concept and critical thinking disposition have an effect on clinical competence in nursing students. Accordingly in order to improve clinical competence, it is necessary to provide practice environment and educational curriculum that enhance the professional self-concept and critical thinking disposition of nursing students.

Effectiveness Validation on Cold Multi-Stage Forging of Aluminum Inner Tie Rod Socket (알루미늄 이너 타이로드 소켓의 냉간다단단조 유효성 검증)

  • Park, Jae-Wook;Choi, Jong-Won;Jeong, Enn-Eun;Yoon, Il-Chae;Kang, Myungchang
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.1
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    • pp.49-55
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    • 2022
  • Recently, the automobile industry has continued to demand lighter materials owing to international environmental regulations and increased convenience. To address this demand, aluminum parts have increased in popularity and are mainly developed and produced through hot forging and cold pressing. However, because this method has low yield and low production efficiency, a new manufacturing method is desirable. In this study, the water capacity efficiency of an aluminum inner tie rod socket was investigated using cold forging that provided a high yield and excellent production efficiency. Mechanical properties were derived through tensile testing of 6110A aluminum materials, and critical fracture factor and process analysis based on experimental data were carried out. The optimized process was applied as a prototype using cold multi-stage forging, and based on the derived results, the formability, productivity, and material efficiency of aluminum inner tie rod socket parts using this cold forging process was verified.

Anemia as a Risk Factor of Mortality and Rehospitalization in Patients with Heart Failure : An Integrative Review (심부전 환자의 빈혈과 사망률 및 재입원 간의 관계에 대한 통합적 고찰)

  • Son, Youn-Jung;Kim, Bo-Hwan
    • Journal of Korean Critical Care Nursing
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    • v.12 no.1
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    • pp.94-108
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    • 2019
  • Purpose : Heart failure (HF) is considered an important medical burden with rehospitalization and mortality. Anemia is a major risk factor associated with the severity of HF. To improve the understanding of the impact of anemia in the population with HF, we explored the prevalence of anemia, its guidelines, relationship between anemia and mortality or rehospitalization, and limitation of reviewed papers of various populations with HF. Method: We used Whittemore and Knafl's integrative review methodology (2005), and thirty research papers were analyzed. PubMed, CINAHL, Cochrane, PsychInfo, Embase, Web of Science were searched for papers published between January 1960-June 2018. Results: Anemia in individuals with HF was primarily defined using the World Health Organization guideline. The prevalence of anemia in patients with HF varied from 9% to 56.7%. Moreover, such a condition significantly increases the prevalence of mortality or rehospitalization in patients with HF. The analyzed majority were non-prospective cohort study including secondary data analysis. Conclusion: Anemia in individuals with HF is a significant risk factor of mortality and rehospitalization. Prospective cohort studies should be designed to identify the optimal value for screening anemia and the impact of anemia on rehospitalization and mortality among HF patients.

Study on Heat Transfer Performance Change According to Long-term Operation Using Carbon Nanotube and Graphene Nanofluid (탄소나노튜브 및 그래핀 나노유체 사용시 장기운전에 따른 열전달성능 변화에 대한 연구)

  • Kim, Young-Hun;Kim, Nam-Jin
    • Journal of the Korean Solar Energy Society
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    • v.37 no.1
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    • pp.15-23
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    • 2017
  • Critical heat flux refers to the sudden decrease in boiling heat transfer coefficient between a heated surface and fluid, which occurs when the phase of the fluid near the heated surface changes from liquid to vapor. For this reason, critical heat flux is an important factor for determining the maximum limit and safety of a boiling heat transfer. Recently, it is reported that the nanofluid is used as a working fluid for the critical heat flux enhancement. However, it could be occurred nano-flouling phenomena on the heat transfer surface due to nanoparticles deposition, when the nanofluid is applied in a heat transfer system. In this study, we experimentally carried out the effects of the nano-fouling phenomena in oxidized multi-wall carbon nanotube and oxidized graphene nanofluid systems. It was found that the boiling heat flux decreased by hourly 0.04 and $0.03kW/m^2$, also the boiling heat transfer coefficient decreased by hourly 11.56 and $10.72W/m^2{\cdot}K$, respectively, in the thermal fluid system using oxidized multi-wall carbon nanotube or oxidized graphene nanofluid.

Stiffness effect of fitting interference for a shrunk rotor (열박음 로터에서 간섭량의 강성 효과)

  • 김영춘;박희주;박철현;김경웅
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.05a
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    • pp.319-324
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    • 2003
  • In general industrial rotating machinery is operated under 3,600 rpm as rotating speed and designed to have critical speed that is above operating speed. So, there was no problem to operate rotating machine under critical speed. But nowadays, they should be operated more than the frist critical speed as usual with the trend of high speed, large scale and hish precision in industries. In case of the large rotor assembly as the trend of large scale, using fitting method of disk or cylinder on shaft is rising for the convenience of assembly and cutting down of manufacturing cost. The shrink fitting is used to assemble lamination part on shaft for manufacturing of rotor of motor or generator in many cases and also is widely used for other machinery. In rotating system, which is compose of rotor and bearing, the critical speed is determined from inertia and stiffness for the rotor and bearings. In case of fitting assembly, analysis and design of the rotor is not easy because the rotor stiffness is determined depend on a lot of factors such as shaft material/dimension, disk material/dimension and assembled interference etc. Therefore designer who makes a plan for hish-speed rotating machine should design that the critical speed is located out of operating range, as dangerous factors exist in it. In order to appropriate design, an accurate estimation of stiffness and damping is very important. The stiffness variation depend on fitting interference is a factor that changes critical speed and if it's possible to estimate it, that Is very useful to design rotor-bearing system. In this paper, the natural frequency variation of the rotor depends on fitting interference between basic shaft and cylinder is examined by experimentation. From the result, their correlation is evaluated quantitatively using numerical analysis that is introduced equivalent diameter end the calculation criteria is presented for designer who design fitting assembly to apply with ease for determination of appropriate interference.

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Analytic Hierarchy Process for Prioritizing Radiation Safety Measures in Medical Institutions

  • Hyun Suk Kim;Heejeong Jeong;Hyungbin Moon;Sang Hyun Park
    • Journal of Radiation Protection and Research
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    • v.49 no.1
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    • pp.40-49
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    • 2024
  • Background: This study aimed to prioritize policy measures to improve radiation safety management in medical institutions using the analytic hierarchy process. Materials and Methods: It adopted three policy options-engineering, education, and enforcement-to categorize safety management measures, the so-called Harvey's 3Es. Then, the radiation safety management measures obtained from the current system and other studies were organized into action plan categories. Using the derived model, this study surveyed 33 stakeholders of radiation safety management in medical institutions and analyzed the importance of each measure. Results and Discussion: As a result, these stakeholders generally identified enforcement as the most important factor for improving the safety management system. The study also found that radiation safety officers and medical physicists perceived different measures as important, indicating clear differences in opinions among stakeholders, especially in improving quality assurance in radiation therapy. Hence, the process of coordination and consensus is likely to be critical in improving the radiation safety management system. Conclusion: Stakeholders in the medical field consider enforcement as the most critical factor in improving their safety management systems. Specifically, the most crucial among the six specific action plans was the "reinforcement of the organization and workforce for safety management," with a relative importance of 25.7%.

Deriving of Critical Factors for Construction Planning in Large Span Roof Construction (대공간 지붕 철골공사의 시공계획 중점관리항목 도출)

  • Lee, Myungdo
    • Journal of Korean Association for Spatial Structures
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    • v.18 no.1
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    • pp.67-75
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    • 2018
  • Steel roof construction is on the most important and critical factors in the large spatial construction and necessary to be prepared under a radical planning. Therefore, the major management factors of steel roofing structure assembly must be critically reviewed during planning. Through the review process, it is necessary to reduce the construction cost, to prevent delays in the construction schedule, and to minimize construction errors. However, domestically due to the lack experience in large spatial constructions, a planning of roof construction is limited to have a radical planning. Especially due to unclear organization of the management factors in hierarchy, using them in reality for construction planning is difficult and reliability is low. Therefore, in this study, the goal is to conduct the major management factors in the large spatial construction. To achieve this, we have reviewed and analyzed the numbers of construction plans and construction reports and conducted a total 68 of the management factors. Based on the conducted factors, we have interviewed 16 experts with experience in large spatial construction. From the interview result, we have deduced the factors scored above 4.20 of 10 for critical factors. The results of this study will be used as a guidance for planning steel roofing structure assembly in large spatial construction. The critical factors will be provided to the site mangers for the quality management of large spatial constructions in practice.

Generalized Solution Procedure for Slope Stability Analysis Using Genetic Algorithm (유전자 알고리즘을 이용한 사면안정해석의 일반화 해법)

  • Shin, Eun-Chul;Patra, Chittaranjan R.;Pradhan, R.
    • Journal of the Korean Geotechnical Society
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    • v.24 no.3
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    • pp.5-11
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    • 2008
  • This paper pertains to the incorporation of a genetic algorithm methodology for determining the critical slip surface and the corresponding factor of safety of soil slopes using inclined slice method. The analysis is formulated as a constrained optimization problem to solve the nonlinear equilibrium equations and finding the factor of safety and the critical slip surface. The sensitivity of GA optimization method is presented in terms of development of failure surface. Example problem is presented to demonstrate the efficiencies of the genetic algorithm approach. The results obtained by this method are compared with other traditional optimization technique.

Design of the Inverter Motor Drive System Applied to PFC using Interleaving Method (인터리빙 PFC를 적용한 모터구동 인버터 시스템 설계)

  • Yoon, Seong-Sik;Choi, Hyun-Eui;Kim, Tae-Woo;Ahn, Ho-Kyun;Park, Seung-Kyu;Yoon, Tae-Sung;Kwak, Gun-Pyoung
    • Journal of the Korean Society for Precision Engineering
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    • v.27 no.4
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    • pp.14-19
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    • 2010
  • In this paper, using interleaved power factor correction how to improve the inverter efficiency studied. Interleaved method can reduce the conduction losses and the inductor energy. Generally, critical conduction mode (CRM) boost PFC converter used low power level because of the high peak currents. if you use the interleaved mode, CRM PFC can be used medium or high power application. interleaved CRM PFC can reduce current ripple for higher system reliability and size of buck capacitor and EMI filter size. Interleaved CRM PFC that is installed in front of inverter can maintain the constant voltage regardless of the input voltage.

Comparative Study of P-T Limit Curves between 1998 ASME and 2017 ASME Code Applied to Typical OPR1000 Reactors

  • Maragia, Joswhite Ondabu;Namgung, Ihn
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.15 no.2
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    • pp.1-8
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    • 2019
  • The integrity of the Reactor Pressure Vessel (RPV) is affected by the neutrons bombarding the vessel wall leading to embrittlement. This irradiation-induced embrittlement leads to reduction in the fracture toughness of RPV materials. This paper presents a comparative study of typical Optimized Power Reactor (OPR)1000 reactor pressure-temperature (P-T) limit curves using the pre-2006 American Society of Mechanical Engineers (ASME) editions used in the power plant and the current ASME edition of 2010. The current ASME Code utilizes critical reference stress intensity factor based on the lower bound of static, while the Pre-2006 ASME editions are based the critical reference stress intensity factor based on the lower bound of static, dynamic and crack arrest. Model-Based Systems Engineering approach was used to evaluate ASME Code Section XI Appendix G for generating the P-T limit curves. The results obtained from this analysis indicate decrease in conservatism in P-T limit curves constructed using the current 2017 ASME code, which can potentially increase operational flexibility and plant safety. Hence it is recommended to use ASME code edition after 2006 be used in all operating nuclear power plants (NPPs) to establish P-T limit curve.