• Title/Summary/Keyword: Critical levels

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Conceptual Design Based on Scale Laws and Algorithms Sub-critical Transmutation Reactors

  • Lee, Kwang-Gu;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.475-480
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    • 1997
  • In order to conduct the effective integration of computer-aided conceptual design for integrated nuclear power reactor, not only is a smooth information flow required, but also decision making fur both conceptual design and construction process design must be synthesized. In addition to the aboves, the relations between the one step and another step and the methodologies to optimize the decision variables are verified, in this paper especially, that is, scaling laws and scaling criteria. In the respect with the running of the system, the integrated optimization process is proposed in which decisions concerning both conceptual design are simultaneously made. According to the proposed reactor types and power levels, an integrated optimization problems are formulated. This optimization is expressed as a multi-objective optimization problem. The algorithm for solving the problem is also presented. The proposed method is applied to designing a integrated sub-critical reactors.

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A Study on Managerial Efficiency in Economic Development (경제발전에 있어서의 경영효율에 관한 연구)

  • 권춘식;배수진
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.5 no.7
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    • pp.33-42
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    • 1982
  • The standard theory of production treats human and non-human inputs in the same way. Inert Areas Theory drops this assumption. One distinction is obvious. Human capital, the source of human inputs, can not be purchased outright by firms. Usually what is purchased are units of labor time. What is critical is directed effort, at or beyond some level of skill. Direct effort, however, involves choice and motivation, and these are the critical variables left out of the standard theory. Leibenstein introduces the concept of "inert areas" by which he means "a set of effort positions whose associated levels of utility are not equal but in which the action required to go from a lower to a higher utility level involves a utility cost that is not compensated for by the gain in utility." This idea is used when discussing the behavior of firm's management.f firm's management.

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Application of inverse reliability method to estimation of flutter safety factors of suspension bridges

  • Cheng, Jin;Dong, Fenghui
    • Wind and Structures
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    • v.24 no.3
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    • pp.249-265
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    • 2017
  • An efficient and accurate algorithm is proposed to estimate flutter safety factor of suspension bridges satisfying prescribed reliability levels. Uncertainties which arise from the basic wind speed at the bridge deck location, critical flutter velocity, the wind conversion factor from a scaled model to the prototype structure and the gust speed factor are incorporated. The proposed algorithm integrates the concepts of the inverse reliability method and the calculation method of the critical flutter velocity of suspension bridges. The unique feature of the proposed method is that it offers a tool for flutter safety assessment of suspension bridges, when the reliability level is specified as a target to be satisfied by the designer. Accuracy and efficiency of this method with reference to three example suspension bridges is studied and numerical results validate its superiority over conventional deterministic method. Finally, the effects of various parameters on the flutter safety factor of suspension bridges are also investigated.

Rapid Energy Transfer Mechanism of F Electronic Excitation to the Vibration of Randomly Distributed $OH^- in KCI

  • 장두전;아철승
    • Bulletin of the Korean Chemical Society
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    • v.19 no.10
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    • pp.1063-1068
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    • 1998
  • The nature of F electronic excitation energy transfer to OH- vibrational levels in KCl crystals is the exchange interaction, although the transfer process exhibits three temporally distinguishable components depending on the distance between excited F center and OH-. The critical distance as well as rate of the major energy transfer process in randomly distributed samples increases rapidly as OH- librational motions become active with temperature rise. The excited state character introduced into the OH- ground electronic state by perturbation is essential for the exchange interaction. The perturbation is brought about by the expanded electron cloud of excited F center for OH- associated to F center, whereas by librations and lattice vibrations perpendicular to the bond axis for isolated OH- . F excitation quenching efficiency by OH- is dependent on the variation of the critical distance rather than the rate as the rate is much faster than the normal F bleach recovery rate.

Developing an Instruments to Measure the Convergence Talent: Building Convergence-oriented Organizations in South Korea (융합지향 조직 구축을 위한 융합인재 측정 도구 개발)

  • Lee, SeoYoung;Kwon, Sangjib
    • Knowledge Management Research
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    • v.20 no.1
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    • pp.77-99
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    • 2019
  • This study aims to examine validity and reliability of the convergence talent measurement. Based on the comprehensive literature review on convergence and convergence talent, we draw 4 main competencies (convergence cognitive, accomplishment, problem solving, and attitude) and 10 critical aspects (creative thinking, critical thinking, cooperation, communication, problem-solving, knowledge accessibility, resource utilization, trust, openness, caring) for building an effective convergence-oriented organization. A validity and reliability test survey were conducted for the analysis to investigate the convergence talent scale. With a data of 151 employees in diverse companies, the results show that the factors demonstrated acceptable levels of validity and reliability. The empirical evidences of our study are 10 key aspects comprising four main dimensions which suggest an available scale for measuring the convergent talent for enhancing convergence-oriented organizations. Our research contributes to the expansion of academic and practical implications on convergence, especially in convergence-oriented organizations.

DEVELOPMENT OF A RESOURCE LEVELING MODEL USING OPTIMIZATION

  • Jin-Lee Kim;Ralph D. Ellis
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.558-563
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    • 2005
  • This paper presents a GA-based optimal algorithm for a resource leveling model that levels the resources of a set of non-critical activities experiencing conflicts simultaneously up to an assumed level of resource rates specified by the planner using a pair-wise comparison of the activities being considered. A parameter called the future float is adopted and applied as an indicator for assigning leveling priorities to the sets of activities experiencing conflicts. A construction project network example was worked out to demonstrate the performance of the proposed method. The histogram obtained using the algorithm proposed was shown to be the same as, or very close to that produced by the existing resource leveling method based on the least total float rule, which shifts non-critical activities individually.

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AN EXAMPLE OF REPRESENTING THREE LEVEL'S SCHEDULES WITHIN SCHEDULE HIERARCHY BY BDM TECHNIQUE

  • Seon-Gyoo Kim
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.445-452
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    • 2011
  • The schedule hierarchy in construction project is generally composed of three levels. The highest level is a milestone schedule and represented by Bar Chart format. The middle level is an integrated project schedule (IPS) and represented by CPM (Critical Path Method) format. The lowest level is a detail working schedule and usually represented by Bar Chart. The traditional scheduling techniques such as ADM (Arrow Diagramming Method) or PDM (Precedence Diagramming Method) cannot represent all kinds of schedule within schedule hierarchy as identical schedule format. However, the BDM (Beeline Diagramming Method) technique can represent all kinds of schedule within schedule hierarchy as identical CPM format. This paper describes the basic concept, principle, interpretation methods, and schedule computation methods of the BDM as a new networking technique that can represent all kinds of overlapping relationships between activities, and then presents an example of representing three level's schedules within schedule hierarchy by the BDM technique.

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Critical Thinking Disposition and Problem-Solving Ability of Dental Hygiene Students (치위생과 학생의 비판적 사고 성향과 문제해결능력)

  • Kim, Ji-Hee;Sung, Hee-Kyung;Kim, Hye-Jin
    • Journal of dental hygiene science
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    • v.14 no.3
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    • pp.356-363
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    • 2014
  • This study attempts to measure the critical thinking disposition and problem-solving ability levels of dental hygiene students and to investigate their correlation. A self-administered survey was conducted with respect to dental hygiene students from three-year colleges in Busan, Ulsan and the Gyeongsangbuk-do region between April 2013 and May 2013. A total of 649 surveys were subject to a final analysis. Critical thinking disposition of the dental hygiene students resulted in a score of 3.20 out of a total of 5.0. Freshmen, students with high academic performance results, students with good interpersonal relations, students with a high level of satisfaction regarding major subject and clinical training and students with no clinical training experience showed a high score for critical thinking disposition. Problem-solving ability of the dental hygiene students resulted in a score of 3.06 out of a total of 5.0. Students with high academic performance results, students with good interpersonal relations and students with a high level of satisfaction regarding major subject and clinical training showed a high score for problem-solving ability. It was found that critical thinking disposition and problem-solving ability had a pure correlation. The critical thinking disposition appeared to problem solving, interpersonal relations, major factors affect satisfaction, was a critical thinking disposition, academic factors affect the ability to problem solve. Regarding education for dental hygiene students, the reinforcement of training to increase critical thinking and problem-solving abilities is necessary and the development of an educational curriculum and change in educational environment that can increase interpersonal skills and communication skills is necessary.

Efficacy and Safety of Sublingual Immunotherapy in Elderly Rhinitis Patients Sensitized to House Dust Mites

  • Kim, Ji Hye;Lee, Ji Ho;Ye, Young-Min;Lee, Jae-Hyun;Park, Jung Won;Hur, Gyu-Young;Kim, Joo-Hee;Lee, Hyn-Young;Shin, Yoo Seob;Yang, Eun-Mi;Park, Hae-Sim
    • Allergy, Asthma & Immunology Research
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    • v.10 no.6
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    • pp.675-685
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    • 2018
  • Purpose: This study aims to determine the efficacy and safety of house dust mite (HDM)-sublingual immunotherapy (SLIT) in elderly patients with AR. Methods: A total of 45 patients aged ${\geq}60years$ with HDM-induced AR who had ${\geq}3$ A/H ratio on skin prick test and/or ${\geq}0.35IU/L$ to both Dermatophagoides farinae and Dermatophagoides pteronyssinus by ImmunoCAP were enrolled in 4 university hospitals. To evaluate additional effects of HDM-SLIT, they were randomized to the SLIT-treated group (n = 30) or control group (n = 15). Rhinoconjunctivitis total symptom score (RTSS), rhinoscopy score, Korean rhinoconjunctivitis quality of life questionnaire, rhinitis control assessment test, asthma control test scores, and adverse reactions, were assessed at the first visit (V1) and after 1 year of treatment (V5); for immunological evaluation, serum levels of HDM-specific immunoglobulin A/IgE/IgG1/IgG4 antibodies and basophil response to HDMs were compared between V1 and V5 in both groups. Results: There were no significant differences in demographics, RTSS, skin reactivity to HDMs, or serum total/specific IgE levels to HDMs (P > 0.05, respectively) between the 2 groups. Nasal symptom score and RTSS decreased significantly at year 1 in the 2 groups (P < 0.05). There were no significant differences in percent decrease in nasal symptom score and RTSS at year 1 between the 2 groups (P > 0.05); however, rhinoscopic nasal symptom score decreased significantly in the SLIT-treated group (P < 0.05). Immunological studies showed that serum specific IgA levels (not specific IgE/IgG) and CD203c expression on basophils decreased significantly at V5 in the SLIT-treated group (P = 0.011 and P = 0.001, respectively), not in the control group. The control group required more medications compared to the treatment group, but there were no differences in adverse reactions. Conclusions: It is suggested that HDM-SLIT for 1 year could induce symptom improvement and may induce immunomodulation in elderly rhinitis patients.

The Effect of Multi-faceted Learning by Application Game-based Student Response System in Nursing Education : Focusing on Kahoot! (간호교육에서 게임기반 학생응답시스템을 적용한 다각적인 학습효과 : Kahoot!을 중심으로)

  • Kim, Yu-Jeong
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.4
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    • pp.255-265
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    • 2021
  • The purpose of this study was to examine the effects of Kahoot!(Game-based Student Response System) on nursing education. This study used an one group Pretest-posttest design. Participants were 179 nursing students from one D university located in Gwangju, Korea. The Kahoot!(Game-based Student Response System) was provided for 6 times. Data were collected between August 26 and October 25, 2019. The collected data was analyzed by descriptive statistics, paired t-test, pearson's correlation coefficient and stepwise multiple regression using IBM SPSS 21.0 program. The results showed that learning engagement(t=-6.257, p=.000) was significantly higher than levels before Kahoot!(Game-based Student Response System), critical thinking disposition(t=-2.163, p=.032) was significantly higher than levels before Kahoot!(Game-based Student Response System), problem solving ability(t=-3.032, p=.003) was significantly higher than levels before Kahoot!(Game-based Student Response System). Significant relationships were found among learning engagement(r=.375, p=.000), critical thinking disposition(r=.286, p=.000), problem solving ability(r=.291, p=.000) and learning satisfaction. The results of stepwise multiple regression indicates that learning engagement(β=.307, p=.000), problem solving ability(β=.158, p=.041) predicts 15.2% in learning satisfaction(F=16.905, p=.000). In conclusion, Kahoot!(Game-based Student Response System) is effective in improving learning engagement and problem solving ability to nursing education.