• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.4
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• pp.223-232
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• 2003

This paper presents a new method driving multiple robots to their goal position without collision. Each robot adjusts its motion based on the information on the goal location, velocity, and position of the robot and the velocity and position of the .other robots. To consider the movement of the robots in a work area, we adopt the concept of avoidability measure. The avoidability measure figures the degree of how easily a robot can avoid other robots considering the following factors: the distance from the robot to the other robots, velocity of the robot and the other robots. To implement the concept in moving robot avoidance, relative distance between the robots is derived. Our method combines the relative distance with an artificial potential field method. The proposed method is simulated for several cases. The results show that the proposed method steers robots to open space anticipating the approach of other robots. In contrast, the usual potential field method sometimes fails preventing collision or causes hasty motion, because it initiates avoidance motion later than the proposed method. The proposed method can be used to move robots in a robot soccer team to their appropriate position without collision as fast as possible.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1687-1689
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• 1998

In this work, the behaviours of conducting wire type particles within the coaxial electrode gap energized with high ac voltage have been systematically investigated using charge simulation method. For this, spheroidal charge is adopted as a image charge for the CSM analysis in order to calculate the acquired charge of the particles which are erected on the surface of the outer electrode. For this purpose, the effects of the lengths and diameters of Cu, Al particles in gas insulated system have been studied by a numerical computation and particle lifting voltage, lifting field, breakdown voltage, acquired charge and travelling distance have been considered. From this, we understand that the particle behaviours have different characteristics according to the particle lengths and diameters. And a possible countermeasure, based on the proposed simulation, has been provided with a view to estimating the flashover voltage of $SF_6$ gas under the 1 atm.

• Journal of Magnetics
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• v.10 no.2
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• pp.48-51
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• 2005

The spin transfer induced magnetization switching has been reported to occur in magnetic multilayer structures whose scope usually consists of one stack of ferromagnetic / non-ferromagnetic / ferromagnetic (F / N / F) materials. In this work, it is shown that: 1) Copper used as a buffer layer between the free Co and the Au cap-layer can clearly increase the probability to get the spin transfer induced magnetization switching in a simple spin valve Co 11 / Cu 6/ Co 2 (nm); 2) Furthermore, when Ruthenium is simultaneously applied as a buffer layer on the Si-substrate, the critical switching currents can be reduced by $30\%$, and the absolute resistance change delta R $[{\Delta}R]$ of that stack can be enlarged by $35\%$. The enhancement of the spin transfer induced magnetization switching can be ascribed to a lower local stress in the thin Co layer caused by a better lattice match between Co and Cu and the smoothening effect of Ru on the thick Co layer.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.389-394
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• 2008

Nowadays Plate Heat Exchanger (PHE) is widely used in different industries such as chemical, food and pharmaceutical process and refrigeration due to the efficient heat transfer performance, extreme compact design and efficient use of the construction material. In present work, PHE is applied in the fresh water generator system. Fresh water generators or desalinators are installed in ship to convert seawater to fresh water using heat from engines. PHE is an important part of a condensing or evaporating system. Among many of factors which should be concentrated on, the heat transfer and pressure drop is most important parts during sizing and rating the performance of PHE. Flow maldistribution is common but it will significantly reduce the heat exchanger performance. In this paper provide a overview of PHE cover basic of theory and conduct a numerical approach for flow distribution in plate channel. An experimental study on the performance of fresh water generator system which developed by plate heat exchanger will presented in future research. Thus, extensive experiment and analysis is required to study the thermal and fluid flow characteristics of PHE.

• Journal of Korean Elementary Science Education
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• v.20 no.2
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• pp.177-186
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• 2001

Recently, introduced open education, there are some models applied several cooperative teaming, but there is no case in applied Jigsaw Ⅱ. So this research is selected objects which are 147 students in the fifth grade in 1999' school year and 143 students in 2000's on Yongwon elementary school. It makes share a partial responsibility for planner, leader, investigator, helper, writer and reporter in the small groups, and apply the Jigsaw Ⅱ model. Qualitative and quantitative analyses show that they have effects of Jigsaw Ⅱ cooperative Learning on Student's knowledge, inquiry ability and attitudes on Elementary School Science Study. The final results are following. The significance of Knowledge has .02 in 1999 and .01 in 2000. Testification of Inquiry ability has 1.75 in 1999 and 2.25 in 2000. The significance of Attitudes has .03 in 1999 and .00 in 2000. Research that has emerged from the cooperative teaming has led us to better understandings of multi purposed roles, interactions, and communities that arise when students work together to team science. Each of students can also cooperative as co-builders, working as equal participants to create a product that is better than that while would have built by either individual alone. Upon asking their intention, cooperative loaming shows more participation.

• English Language & Literature Teaching
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• v.16 no.3
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• pp.339-363
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• 2010

The purpose of this paper is to investigate how the English classes in secondary schools in Korea are in terms of communicative nature. After literature study, COLT parts A and B were used to analyze three kinds of English classes: a common class type taught by a school teacher who had won 1st prize at TEE contest, a team teaching class taught by NNS and NS, and a model class taught by a pre-service English teacher. Their communicative English classes were videotaped and transcribed for analysis by COLT. The results of the study revealed that students participated in the classes mostly as a unit and, therefore, did not get many meaningful chances to speak English. Second, creative language-use opportunities were barely found during classes. Third, the group work seemed to be prepared before the class, not to be done during the class. Therefore it is likely to be learned from memorization rather than meaningful communication. These results suggest English classes in schools be more communicatively oriented for successful English learning. Further study should be conducted in order to make English classes more communicative to help students communicate their genuine messages in English and to help teachers teach English efficiently.

• Journal of Community Nutrition
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• v.7 no.3
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• pp.149-155
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• 2005

This exploratory study investigated the software programs utilized by clinical dietitians and their perceptions on the use of information technology. The study focused on the use of specialized software for dietetics, general software for any office use and the Internet. A self-administered survey was used to collect data from clinical dietitians identified in the Kentucky Dietetic Association Directory 2003-2004. The survey was conducted in March through April, 2004. A total of 22 responses were collected, which yielded a response rate of $68\%$. Findings suggest that computer use has become a routine for optimal clinical practice ; major specialized software programs are used for nutrition assessment, nutrition analysis and menu development. Use of specialized software appears to be unassociated with dietitians' age and years of experience ; however, the associations are indicated between use of specialized software and education level as well as their specialty ; word processing and spreadsheet are the major general software used. Internet is used mainly for information search and communication. Respondents perceived that overall work efficiency and productivity significantly increased with computer use. The complexity of software is the major barrier encountered so training is the most needed support by the department. Strategic promotion on the use of specialized software should be targeted to the management team of the hospitals/facilities.

• Journal of Korean Academy of Nursing Administration
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• v.22 no.2
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• pp.199-208
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• 2016

Purpose: The purpose of this study was to investigate the influence of patient safety culture and perceived teamwork on the safety control of nurses. Methods: This study was conducted as a descriptive cross-sectional survey with 141 nurses who worked in a tertiary hospital with over 1,000 beds in S city, Gyeonggi province. Data were collected using structured questionnaires from July 20, to July, 31, 2015. Results: The average work period for nurses participating in the research was 8.84 years. The perceived teamwork and patient safety culture were positively correlated with safety control. The regression model with patient safety culture, perceived teamwork and clinical career against safety control was statistically significant (F=10.16, p<.001). This model also explained 37.1% of safety control (Adj. $R^2=.37$). Especially, communication (${\beta}=.27$, p=.023) of patient safety culture, clinical career (${\beta}=.26$, p<.001), mutual support (${\beta}=.24$, p=.042), and team leadership (${\beta}=.24$, p=.018) in perceived teamwork were identified as factors influencing safety control. Conclusion: The findings of this study imply that a broad approach including teamwork and patient safety culture should be considered to improve the safety control for nurses.

• The Journal of Korean Academic Society of Nursing Education
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• v.17 no.2
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• pp.246-256
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• 2011

Purpose: With the decrease in available clinical sites, a decrease in adequately prepared clinical faculty, and demand to prepare health care students to begin work, we need alternative methods to teach clinical skills for health care professionals. The use of simulation as an educational process that can replicate clinical practices is becoming popular in nursing. Therefore, this study was conducted to review directions of simulation-based learning in nursing education. Methods: A systematic review of quantitative studies was undertaken using Medline, KERIS, and KISS. The primary search terms were simulation and nursing. Reference lists from relevant papers and the websites of relevant nursing organizations were also searched. Nine studies met inclusion criteria and were analyzed in detail. Results: All studies reported simulation as a valid teaching/learning strategy. Six of the studies (66.7%) showed that simulation technology was a practical and successful model to use in teaching a variety of clinical skills for nursing students and nurses. Conclusion: Simulation may have some advantages over other teaching methods, depending on the scenario, context, topic, and method. Further study is needed to determine the effect of team size on learning and to develop a universal method of outcome measurement.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.4
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• pp.474-485
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• 2017

Purpose: The purpose of this study was to identify a causal relationship among major satisfaction, career decision autonomy, and career search behavior of nursing college students in clinical practice experience. Methods: Data were collected using a self-reported questionnaires from 197 nursing students in S city from December 1 to 23, 2016. These were then analyzed by descriptive statistics, ANOVA, t-test, Pearson correlation coefficient, and multiple regression using SPSS/PC+ program. Results: The results suggest that major satisfaction was correlated with career decision autonomy; likewise, major satisfaction was correlated with career search behavior. The factors influencing career search behavior were grades and major satisfaction. Conclusion: It is necessary to develop a learning method considering interest and aptitude to increase the satisfaction of the major and to apply the various programs to understand the self and the work environment so as to determine how desirable the course will be.