• Journal of Power System Engineering
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• v.17 no.5
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• pp.44-51
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• 2013

This paper proposes and analyzes recycling of optical phonons emitted by nonradiative decay, which is a major thermal management concern for high-power light emitting diodes (LED), by introducing an integrated, heterogeneous barrier cooling layer. The cooling is proportional to the number of phonons absorbed per electron overcoming the potential barrier, while the multi-phonon absorption rate is inversely proportional to this number. We address the theoretical treatment of photon-electron-phonon interaction/transport kinetics for optimal number of phonons (i.e., barrier height). We consider a GaN/InGaN LED with a metal/AlGaAs/GaAs/metal potential barrier and discuss the energy conversion rates. We find that significant amount of heat can be recycled by the barrier transition cooling layer.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.169-174
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• 1998

An 1200-day time-dependent fuel-management for the transition from 37-element fuel to CANFLEX-NU fuel in a CANDU 6 reactor has been simulated to show the compatibility of the CANFLEX-NU fuel with the reactor operation. The simulation calculation were carried out with the RFSP code, provided by cell averaged hel properties obtained from the POWDERPUFS-V code. The refueling scheme for both fuels was an eight bundle shift art a time. The simulation results show that the maximum channel and bundle powers were maintained below the licence limit of the CANDU 6. This indicates that the CANFLEX-NU fuel bundle is compatible with the CANDU 6 reactor operation during the transition period.

• Journal of Korean Society on Water Environment
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• v.30 no.4
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• pp.429-440
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• 2014

This study was conducted to investigate the main cause of water quality deterioration during the spring season in the transition zone between the South Han River and the river-reservoir Paldang. A water quality model modified from QUAL2E (U.S.EPA) was used, and the model showed that eutrophication and algal production in the low flow season affected about 60% of the organic pollution at the downstream of the South Han River. This result means that phosphorus control is prior to external organic material management to ameliorate the deterioration of water quality in the water body.

• IE interfaces
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• v.13 no.4
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• pp.694-702
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• 2000

For the graceful transition from the analog to digital TV systems, a systematic frequency assignment scheme must be incorporated into the transition planning procedure. In this study, we have studied the frequency assignment methodology for the efficient management of the limited spectrum resources. By applying the graph-theoretic approach, this study developed a new solution method for additional frequency assignment problem whose objective is to assign available frequencies for newly generated requirements (digital TV stations) with minimum reassignment of the preassigned frequencies to LPTV stations while meeting the interference-related constraints. The proposed algorithm can be effectively applied not only to the current digital TV introduction phase but also to the development phase with some further development. This study can be utilized as the basis for the future study on frequency assignments that aims at graceful transition from analog TV to digital TV.

• Industrial Engineering and Management Systems
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• v.12 no.2
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• pp.143-150
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• 2013

The number of airline passengers in China has rapidly increased, so understanding the relationship between brand equity of airlines in China and ticket purchase intention of Chinese passengers is important for airline business success in China. Using the structural equation modeling, this study explores the relationships among determinants of brand equity as well as the relationships between brand equity, transition cost, and purchase intention. The major findings are: brand equity of airlines directly influences purchase intention; transition cost directly influences brand equity; and transition cost indirectly influences purchase intention in China. In addition, the results show that marketing strategies using the airline brand can be more effective for certain customer groups, including high income customers, married customers, government servants, and businessmen.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.854-861
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• 2005

The functional behavior of a portable consumer electronic (PCE) product is nearly all expressed with human-machine interaction (HMI) tasks. Although physical prototyping and computer aided design (CAD) software can show the appearance of the product, they cannot properly reflect its functional behavior. In this paper, we propose a virtual prototyping (VP) system that incorporates virtual reality and HMI functional simulation in order to enables users to capture not only the realistic look of a PCE product but also its functional behavior. We obtain geometric part models of the product and their assembly and kinematics information with the help of CAD and reverse engineering tools, and visualize them with various display tools. We adopt state transition methodology to capture the HMI functional behavior of the product into a state transition chart, which is later used to construct a finite state machine (FSM) for the functional simulation of the product. The FSM plays an important role to control the transition between states of the product. The proposed VP system receives input events such as mouse clicks on buttons and switches of the virtual prototype model, and it reacts to the events based on the FSM by activating associated activities. The VP system provides the realistic visualization of the product and the vivid simulation of its functional behavior. It can easily allow users to perform functional evaluation and usability testing. Moreover, it can greatly reduce communication errors occurring in a typical product development process. A case study about VP of an MP3 player is given to show the usefulness of the proposed VP system.

• Journal of Science and Technology Studies
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• v.8 no.1
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• pp.1-28
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• 2008

This study investigates the characteristics and implications of the newly emerging socially-oriented innovation policy. The socially-oriented innovation policy has systemic views on the evolution of socio-technical system and innovation policy. It's ultimate goal is the transition toward sustainable socio-technical system and it takes "strategic niche management" approach for the transition policy. The governance structure of the policy is more open to the public actors, such as social service organizations and public institutes. As a case study, "the Technology-based Policy for the Enhancement of Quality of Life", which is the first comprehensive socially-oriented policy of Korea, is examined and it is suggested that the policy has some limitations because of the path dependency of targeting-oriented and catching-up style innovation policy of Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.155-155
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• 2022

Low head, ogee spillways is popularly used to defense against floods as well as to provide water for irrigation. Spillway is also used to assess compliance with water quality regulations by controlling amount of discharge to the downstream of a channel. For the purpose of water resource management and/or environmental aspects as explained above, the flow discharge through spillways need to be correctly rated as a function of geometry and hydraulic variables. Typically, four flow conditions are encountered during the operation of spillway: (a) uncontrolled free flow (UF); (b) uncontrolled submerged flow (US); controlled free flow (CF); and controlled submerged flow (CS), and each condition has a unique rating equation. However, one of the tricky part of the spillway operation is finding correct flow type over the spillway because structures can operate under both submerged and free flow conditions, and the types are continuously changing over time depending on the amount of discharge, head water and tail water elevation. Quite obviously, if the wrong rating curve relationship is applied because of misjudgment of the flow type due to a transition, a serious error can occur. Thus, an hydraulic model study of one of spillway structure located in South Florida was conducted for the purpose of developing transition relationships. In this presentation, US to UF transition is highlighted.

• Journal of Korean Clinical Nursing Research
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• v.25 no.3
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• pp.237-250
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• 2019

Purpose: The aim of this study was to investigate the satisfaction of newly graduated nurses with educational programs and their experiences in role transition. Methods: Data were collected from November 1 to December 15, 2018 and 483 new graduate nurses working at 15 tertiary hospitals and 10 general hospitals participated. For data collection, self-report questionnaires including the Casey-Fink Graduate Nurse Experience Survey tool and satisfaction with education were used. Data were analyzed using descriptive statistics, t-test, and one-way analysis of variance. Results: Satisfaction with education ranged from 3.09 to 3.27, and satisfaction with preceptors was 3.45(maximum 4). The skill that new nurses ranked as most difficult during the first 3 months was charting/documentation, and throughout a whole year, the top 4 difficult skills were cardiopulmonary resuscitation/emergency response, ventilator care, end-of-life care, and prioritization/time management. In comfort/confidence, new graduates felt most comfortable with support and least comfortable with patient safety. More than 50 percent of new graduates experienced stress during role transition, and the most frequently experienced stressors were related to job performance and personal life. Levels of satisfaction with education and comfort/confidence differed according to the hospital type and number of preceptors for new nurses. Conclusion: In order to facilitate the transition of new graduate nurses to professional nurse, an extended period of education, systematic and standardized transition programs, and continuous support during the first year of practice are required.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.221-229
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• 2019

The purpose of this study was to identify the relationships between nursing competency and emotional intelligence and nurse role transition of nursing students. Study participants were 134 nursing students of university in Chungnam province. Data were collected with the use of self-administered questionnaires from November 1 to December 10, 2018. Collected data were analyzed using the IBM SPSS 20.0 program. Nurse role transition of nursing students showed positive correlation with nursing competency(r=.79, p<.001) and emotional intelligence(r=.59, p<.001). Factors influencing nurse role transition of nursing students were nursing competency(${\beta}=.66$, p<001) and emotional intelligence(${\beta}=.22$, p=.001), which accounted 67.8%. These results indicate that various educational programs to increase nursing competency and emotional intelligence of nursing students are needed to increase nurse role transition. Studies on the effectiveness of provided programs are also needed to provide more effective programs.