• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.167-168
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• 2005

The operational characteristics of the integrated three-phase flux-lock type superconducting fault current limiter (SFCL) were analyzed. The suggested three-phase SFCL consisted of a three-phase flux-lock reactor and three high-Tc superconducting (HTSC) elements. The former has three windings wound on an iron core, each of which has the same turn's ratio between coil 1 and coil 2. The latter are connected in series with coil 2 of each phase. The integrated three-phase flux-lock type SFCL showed the operational characteristics that the fault phase could affect the sound phase, which resulted in quenching the HTSC element in the sound phase. Through the computer simulation applying numerical analysis for its three-phase equivalent circuit, the fault current limiting characteristics of the integrated three-phase flux-lock type SFCL according to the ground fault types were compared.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1630-1642
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• 2016

Inter-domain routing is the most critical function of the Internet. The routing system is a logical network relying on the physical infrastructure with geographical characteristics. Nature disasters or disruptive accidents such as earthquakes, cable cuts and power outages could cause regional failures which fail down geographically co-located network nodes and links, therefore, affect the resilience of inter-domain routing system. This paper presents a model for regional failures in inter-domain routing system called REFER for the first time. Based on REFER, the resilience of the inter-domain routing system could be evaluated on a finer level of the Internet, considering different routing policies of intra-domain and inter-domain routing systems. Under this model, we perform simulations on an empirical topology of the Internet with geographical characteristics to simulate a regional failure locating at a city with important IXP (Internet eXchange Point). Results indicate that the Internet is robust under a city-level regional failure. The reachability is almost the same after the failure, and the reroutings occur at the edge of the Internet, hardly affecting the core of inter-domain routing system.

• Journal of Gastric Cancer
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• v.15 no.2
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• pp.121-126
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• 2015

Purpose: We evaluated the socio-personal and clinical factors that can affect preoperative quality of life to determine how to improve preoperative quality of life in patients with gastric cancer. Materials and Methods: The preoperative quality of life data of 200 patients (68 females and 132 males; mean age $58.9{\pm}12.6years$) with gastric cancer were analyzed according to socio-personal and clinical factors. The Korean versions of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core (QLQ) 30 and the EORTC QLQ-STO22, a gastric cancer-specific module, were used to assess quality of life. Patients were asked to complete the questionnaire preoperatively by themselves. Results: Patients with a higher academic background and stage I disease tended to have higher global health status scores. Highly educated younger men had better physical functioning scores. Highly educated and well-nourished patients with stage I cancer had higher role functioning scores. Married patients had better emotional scores. The symptom scales were affected by sex, age, education level, nutrition, and cancer stage. Conclusions: Preoperative quality of life in patients with gastric cancer can be improved by nutritional support and treatment of symptoms caused by disease progression. Psychological support may be helpful for patients with a poor quality of life.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.7
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• pp.307-314
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• 2001

A moving coil linear oscillatory actuator is consisted of the NdFeB permanent magnets with high specific energy as the stator, a coil-wrapped nonmagnetic hollow rectangular structure and an iron core as a pathway for magnetic flux. The variation of mover position and the consequent changes of coil flux path affect the coil inductance, because coil flux leaks at the open region of LOA stator. The interaction between permanent magnet and armature field is to shift the airgap flux density variation due to the magnet alone by a certain amount. The unbalanced reciprocation force due to armature reaction field decreases the advantage of moving coil LOA, such as a high degree of linearity and controllability in the force ad motion control. This paper firstly describes the coil inductance, the deviation of flux density, and the unbalanced reciprocation force, which are derived form the permeance model of LOA. Secondly, the analytical method are verified using the 2D finite element method and tests. Finally, the dynamic simulation algorithm taking the armature reaction effect and variable inductance into account, is proposed and confirmed through the experiment.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.469-474
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• 1997

To provide tile information ell severe accident progression is very important for advanced or new type of nuclear power plant (NPP) design. A parametric study, therefore was performed to investigate the effect of thermal hydraulic design parameters ell severe accident progression of pressurized water reactors (PWRs), Nine parameters, which are considered important in NPP design or severe accident progression, were selected among the various thermal hydraulic design parameters. The backpropagation neural network (BPN) was used to determine parameters, which might more strongly affect the severe accident progression, among mile parameters. For training. different input patterns were generated by the latin hypercube sampling (LHS) technique and then different target patterns that contain core uncovery time and vessel failure time were obtained for Young Gwang Nuclear (YGN) Units 3&4 using modular accident analysis program (MAAP) 3.0B code. Three different severe accident scenarios, such as two loss of coolant accidents (LOCAs) and station blackout(SBO), were considered in this analysis. Results indicated that design parameters related to refueling water storage tank (RWST), accumulator and steam generator (S/G) have more dominant effects on the progression of severe accidents investigated, compared to tile other six parameters.

• Management & Information Systems Review
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• v.3
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• pp.47-76
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• 1999

Management Information System(MIS) User satisfaction, which was introduced at the earlier 1990's, has become a core way of strategic method. But domestic companies have little experience toward this concept and the methodological knowledge was not cumulated yet. So the definition of User satisfaction, as well as the validity and objectivity toward the estimation, is being under discussion In this report we will contain the contents as follows, 1) investigate limitations of exposed theories about Methodology, 2) look into the situations and handicaps of User satisfaction estimation which is being used in practical domains on company, 3) search for the better way in application through comparative analysis between case study of customer satisfaction structure by structural equation model and by ordinary estimation model. We have conclusions through model that Index values like GFI AGFL RMR are accepted as within limited range for estimating validity of used model. so we can expect to use the results for deduce accurate User satisfaction index. Therefore satisfied Users became lesser at complaint behavior instead higher at repurchase likelihood, while unsatisfied Users became lower. Results as above are accordance with the previous studies, and that proves ACSI model to be applied toward local MIS Users' case. Even though the scopes of this research are restricted in domestic market of MIS Users, ACSI model itself has developed with the purpose for compatibility toward inter-company and inter-industry. So this model can be applied beneficially in the future study to analyse the extent that latent variables affect to User satisfaction.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.290-297
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• 2020

Purpose: This study aimed at exploring the impacts of organizational conflict and job satisfaction on the turnover intention among dental technicians. Methods: This study utilized a descriptive research design. A structured questionnaire was administered to 159 dental technicians. Of the collected questionnaires, data from 127 valid questionnaires were analyzed using t-tests, analysis of variance, Pearson's correlation coefficient, and hierarchical multiple regression using the IBM SPSS 20.0 statistical package. Results: A positive correlation was identified between organizational conflict and turnover intention (r=0.46, p<0.001); however, a negative correlation was shown between job satisfaction and turnover intention (r=-0.50, p<0.001). A hierarchical multiple-regression model was employed to analyze working hours, unfair treatment from dentists and dental hygienists, organizational conflict, and job satisfaction, which contributed to providing an explanation to 39% of the turnover intention of dental technicians (F=14.16, p<0.001). Furthermore, organizational conflict (β=0.32, p<0.001), job satisfaction (β=-0.31, p=0.003), and working hours (β=0.21, p=0.010) were all shown to affect turnover intention. Conclusion: The impact of the negative consequences of organizational conflict and working hours on the turnover intention should be considered within core strategies for increasing the turnover periods for dental technicians.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.170-173
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• 2007

Cruciform conjugated molecule, 4(DP3T)-benzene bearing terthiophene moieties has been synthesized through Horner-Emmons Reaction using 5-dodecyl-5"-aldehyde-[2,2';5',2"] terthiophene as dendrons and octaethyl benzene- 1,2,4,5-tetrayltetrakis(methylene)tetraphosphonate as the core unit; this molecule has been fully characterized. The terthiophene-based molecule exhibits good solubility in common organic solvents and good self-film forming property. They are intrinsically crystalline as they exhibit well-defined X-ray diffraction patterns from uniform orientations of molecules. Thus, intermolecular interaction can be enhanced to affect the carrier transport phenomena after annealing at $148^{\circ}C$. The semiconducting property of 4(DP3T)-benzene have been evaluated in organic field-effect transistors. 4(DP3T)-benzene exhibit carrier mobility as high as $(6.6{\pm}0.5)$ ${\times}$ $10^{-6}cm^2V^{-1}s^{-1}$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.5
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• pp.359-366
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• 2008

A two-dimensional thermal model of proton exchange membrane fuel cell with large active area is developed to investigate the performance of fuel cell with large active area over various thermal management conditions. The core sub-models of the two-dimensional thermal model are one-dimensional agglomerate structure electrochemical reaction model, one-dimensional water transport model, and a two-dimensional heat transfer model. Prior to carrying out the simulation, this study is contributed to set up the operating temperature of the fuel cell with large active area which is a maximum temperature inside the fuel cell considering durability of membrane electrolyte. The simulation results show that the operating temperature of the fuel cell and temperature distribution inside the fuel cell can affect significantly the total net power at extreme conditions. Results also show that the parasitic losses of balance of plant component should be precisely controlled to produce the maximum system power with minimum parasitic loss of thermal management system.

• Journal of the Korea Safety Management & Science
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• v.4 no.2
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• pp.71-81
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• 2002

Today's environment of enterprise is changing. They have to face customer' demands with the right product, the right service and supply them at the right time. And also cut down logistics and inventory cost and bring up the profit as much as they can. This means the change of putting enterprise first in importance to putting customer first importance. therefore to correspond to customer's demand, shorting lead time is becoming a essential condition. The answer to this changes of environment is supply chain management. In the Supply chain, The ATP function doesn't only give customers to conformation of delivery. It can be used by the core function with ATP rule that can reconcile supplies and demands on the supply chain. Therefore We can be acquire the conformation about on the due date of supplier by using the ATP function of management about real and concurrent access on the supply chain, also decide the affect about product availability due to forecasting or customer's orders through the ATP. In this paper, It consolidates the necessity on a CTP and analyzes data which is concerned of ATP. Under the these environments, defines the ATP rule that can improve the customer value and data flow related the LTV(Life Time Value) and builds on a algorithm.