• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.6
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• pp.602-611
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• 2004

Servo system has commonly adapted PI controller with fixed gains, because of its simplicity and determinative relationship among the parameters. The fixed gains PI system may be applied well to some operation conditions, but not non-linearities, complex and time variant operation conditions. For solving these problems, another conventional method, 'variable gun schedule according to speed', is published. The value of gain is determined according to the absolute value of the mover real speed. In this paper, FSTPIC(Fuzzy Self-Tuning PI Controller) is proposed based on various experiences to rapidly reduce speed error and to secure a good speed response characteristics. The effectiveness of proposed algorithms is demonstrated by comparing to two conventional gain systems via 4-quadrant operation.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.169-173
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• 1997

Most conventional lithography systems have been oriented to fabricate electronic devices. Therefore, it is not so easy to fabricate large aspect ratios of waveguide patterns with those systems. When considering costs and efficiencies, a laser lithography system provides number of benefit in realizing waveguide patterns. However, because the conventional laser lithography system could make only positive tone masks, it is inconvenient in determining the direction of the waveguide. A simple and reliable technique to produce negative tone masks was developed by using the laser beam writing. This technique was not sensitive to environmental situations such as dust, vibration, intensity variation. Making use of the technique a variety of device patterns such as Y-branch, directional coupler, and highly smooth S-shape bend could be successfully fabricated with a good contrast.

• The Journal of Korean Association of Computer Education
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• v.16 no.5
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• pp.59-68
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• 2013

The purpose of this study is to analyze the satisfaction and effective variables in online learning for low-income students. An Web-survey was conducted to measure its satisfaction and effectiveness. 285 students participated in the study. T-test and ANOVA were used to analyze the data. The result of satisfaction was fairly positive. In addition, there were differences in effectiveness. In specific, the each group of female, elementary school, higher level of achievement, and higher level of self-regulated learning group students showed higher satisfaction than the others. Suggestions and future research are discussed.

• Korean Institute of Interior Design Journal
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• v.21 no.6
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• pp.212-223
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• 2012

The "Eco-friendly", "Green" concepts was began around 1992 after the Rio Environmental Summit, and the need for sustainable development globally widespread. The green building certification system was began around 2000 and the concept of green building was started in the late 1990s. The green building, which welcomes a period of radical change, is for the survival of the Earth "climate change" and reducing energy consumption in building sector. In this architecture of eco-friendly concept, the green building is rapidly expanding and existing as a ecological environment preservation. Moreover, the realization of zero energy house is to mandate for new buildings in 2025. The aim of further eco-friendly is through the prior ecosystems to restore and product energy for the 9 Green Building model houses in this paper. Building in the concept of ecology is to show about change into 7R's from the 3R's. The "Reduce", "Reuse", "Recycle" consisting of "3R's" is correlated with the traditional to the present Green Building Design. U.S. NCARB (National Council of Architectural Registration Boards) change into the concept of 7R's as "Receive", "Restore", "Respect" and "Remember", added to "3R's". In this paper, the 9 Green Building model houses do not meet the criteria of 7R's. But, the Green Tomorrow of Samsung C & T Corporation meet the 6 criteria for 7R's. This company is most comfortable at low carbon Green Building model houses. Conclusionally, introduction of eco-friendly technologies and amenities for the health of human and natural community life is to advance eco-friendly construction and enhance brand value of housing. By the way, The problem of eco-friendly architecture is initial investment and maintenance. Therefore, eco-friendly architecture and government has to try solving of this difficulty.

• Resources Recycling
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• v.4 no.4
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• pp.16-21
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• 1995

When waste t~re/~vastmz otor oil is pyrolyzed. most of them hecome gaseous produds. and thc remaining onc, whascwelght is ahout in% oi the waste Ore, is pyrolyced residue mnstly composcd oi ca~bnn black A rescsrcll was canicrl nut loutilize lhe pyralyred residue of waste tnelwuste lnotol 011 us retnin~cing agent of asphall concrete, bescd on iolelg~r lesearchrepurl. This shows thal the properlies ol asphall concrele ~nclud~cd~ugl ah~l~tyre, sistance to Tear. temperature-v~scusilysusceptil,ilily u e g reatly improved when lhe pellellrcd hrln aI carlmn hlack usmg petroleum o ~als a hinder Iar ihe pellels isused with asphalt. The surface of the pyralyred resirh~ei s covned by ocl film and thla lnakes good comllatibllity with asphallIn order lo ulilk pyrolyzed residue as a reinforcing agenl oi lhe itsphalt concrete, various tests such as Marshnll tcsi, wheeltracking, and revelhng test has been carried out a1 KLER, Ko~ea I-lighway Coo~poration, and TCMO. Tcst lcsults satirry KSslandard, show "npmvements an the dynam~cs tab~l~lzym, d incrcase reslslance to wear at cold telnpelatule Invrsligadon wascarlied oul to sludg the possibility of soil pallul~on when pyrolyzed residue is used as a tzmioicing agenl. E~pcrimentalresulls show the rcsidue contained in thc asphall docs not cause cnv~ranma~lparlo blems.e cnv~ranma~lparlo blems.

• International Area Studies Review
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• v.15 no.1
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• pp.267-288
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• 2011

As world trade becomes more active and expansive, job mobility has progressed correspondingly in growth. In particular, high-skilled scientists (including advanced-degree holders) now possess the option of various occupational and residential mobilities. We explain the "brain drain" by using two empirical examples. One concerns the U.S. experience of foreign-born Ph.D holders living and working in the United States. The other pertains to the Korean experience, where Korean-origin and foreign-born experienced scientists are actively recruited by the government. We also explore the necessary conditions for recruiting and keeping advanced-skilled scientists, the attainment of which will result in strong future economic growth.

• Journal of East-West Nursing Research
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• v.30 no.1
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• pp.51-59
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• 2024

Purpose: The purpose of this study was to determine the effect of preoperative guidance and operating room environment experience using virtual reality on increasing satisfaction with information and reducing anxiety in preoperative patients undergoing general anesthesia and local anesthesia. Methods: A non-equivalent control group quasi-experimental design was employed. The participants were 80 surgical patients from 4 wards (40 experimental group and 40 control group) of the general hospital located in Gyeonggi-do. Data collection was conducted from June to November 2023 after completing the control group survey in January 2023. Data were analyzed using Chi-square, t-test, and Mann-Whitney U test using SPSS 23.0 program. Results: Satisfaction with preoperative information was higher in the experimental group than that of the control group. Additionally, anxiety related to surgery in the experimental group was significantly lower than that of the control group. The preoperative state anxiety score in the experimental group was not significantly lower than that of the control group. Conclusions: These results suggest that providing patient education and information using virtual reality technology can not only alleviate patients' anxiety related to surgery, but also have the potential to be used as an effective intervention to improve positive patient experiences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2629-2635
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• 2011

This study carried out questionnaire survey and experiment on oral hygiene effects according to the actual condition of using oral care products and the amount of toothpaste used targeting 40 freshmen and sophomores in dental hygienics in some universities from November 8, 2010 to November 26. The collected data was analyzed by using SPSS WIN 15.0 program. The following conclusions were obtained. 1. The result of actual condition of toothbrushing is as follows. As the answer of a question about whether or not toothbrushing after every meal at ordinary times, the largest was 47.5% of being average. The occasion of toothbrushing before going to bed at ordinary times was the largest with 47.5%. The daily toothbrushing frequency was 3 times mostly and the general toothbrushing method at ordinary times was a rolling method. The frequency of exchanging toothbrushes for the past 1 year was 3 times, which is the largest with 45.0%. 2. As a result of the actual condition of using oral care products, the majority of students don't use electric toothbrush, interdental brush, or mouth-rinse except dental floss. Accordingly, there need to be education and promotion with diverse methods so that a patient oneself can prevent oral disease by selecting and using oral care products that are proper for each individual. Also, it was indicated that there is no big difference in oral hygiene effects depending on the amount of toothpaste used. Thus, to avoid wasting toothpaste, we need to educate and promote to use the amount of toothpaste under 0.3g.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.379-387
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• 2020

This exploratory study evaluated various factors influencing the level of nursing self-confidence in the performance of core nursing skills among nursing students. This study surveyed 131 senior nursing students in U city with a structured self-report questionnaire analyzed by SPSS 23.0 software. The average perception scores for importance, problem-solving process, and self-confidence in the performance of core nursing skills were 4.73, 3.57, and 3.90, respectively. The most significant factors affecting self-confidence in the performance of core nursing skills included problem-solving process (β=.33, p=.001) and nursing satisfaction (β=.27, p=.019). These variables explained 15% of the total variance in self-confidence in the performance of core nursing skills. Based on the results of this study, it is necessary to perform research in order to improve the self-confidence of performing core basic nursing skills among nursing students, and the department of nursing defines students' problems by suggesting changes in the practice environment and various nursing situations to improve interpersonal skills. Therefore, it is necessary to develop a curriculum that can be solved and a program to increase nursing satisfaction.

• Korean Journal of Construction Engineering and Management
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• v.1 no.1 s.1
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• pp.87-94
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• 2000

Crack sealing, a routine and necessary part of pavement maintenance, is a dangerous, costly, and labor-intensive operation. Within the North America, about ${\$}200$ million is spent annually on crack sealing, with the Texas Department of Transportation (TxDOT) spending about ${\$}7$ million annually (labor alone accounts for over 50 percent of these costs). Prompted by concerns of safety and cost, the University of Texas at Austin, in cooperation with TxDOT and the Federal Highway Administration (FHWA) has developed a unique computer-guided Automated Road Maintenance Machine (ARMM) for pavement crack sealing. In 1999, successful field tests have been undertaken in 8 States around the U.S. This paper first describes significance of the automated crack sealing and technical advances in automated crack sealers including the ARMM, developed in the U.S. It then discusses the ARMM's field implementation and performance evaluation results, and improvements and modifications suggested through the technology evaluation during the field trials. Current research efforts and future work plans in its further development are also presented in this paper.