• Proceedings of the KACD Conference
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• 2001.11a
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• pp.579-579
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• 2001

One of the most important factors for the clinical success of adhesive posterior restorations is marginal adaptation. This property is very closely related to mechanical properties and to the shrinkage behavior of composite materials. Most of modem composite materials are light-cured. This is why the first part of this lecture will be confined to our recent research on light curing, such as plasma polymerization, LED polymerization and the power of modem halogen lamps. In the second part of the lecture the shrinkage properties such as dimensional shrinkage and shrinkage forces of different light curing materials and during different curing procedures will be discussed. Finally, in the third part of the lecture, marginal adaptation before and after loading in different cavity classes and by using different restorative techniques and curing procedures will be presented. Data will also be given on wear resistance, abrasiveness against opposing cusps and postcuring of composite materials.(omitted)

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.4
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• pp.503-512
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• 2001

A new adaptation algorithm for the digital predistorter is presented. The proposed technique employs the real-time transmitted signals through HPA for the table update. Hence the proposed algorithm does not depend on modulation format and the signal transmission of HPA is not affected during the adaptation process. The experimental results are presented to verify the proposed method and we obtained about 8.4 dB of ACPR improvement.

• Korean Journal of Social Welfare
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• v.47
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• pp.243-271
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• 2001

This study examines family relationship among North Korean migrant families in early adaptation (approximately, up to $5{\sim}6$ years after arrival in the South). Family cohesion, communication, power relationship, and conflicts and domestic violence among family members were examined by the perceptions of 67 male and female householders and their spouses. In the four areas of family relationship, the subjects have quite positive perceptions and shows no critically significant difference on the perceptions between before and after arrival. However, positive perception on family relationship gradually decreases as the length of time of in the South increases with linear or nonlinear patterns according to subcategories of family relationship. These findings suggest several social work practice implications in resettlement assistance for the North Korean migrant families.

• Journal of Biomedical Engineering Research
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• v.45 no.2
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• pp.57-65
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• 2024

Recently, several studies have been conducted to lower the cost of transport of human by adding external joint stiffness elements. However, it has not been clearly elucidated whether adaptation time is required for human subjects to adapt to the added external joint stiffness. In this study, carbon plates in the form of shoe midsoles were added to the metatarsophalangeal joint, and the lower limb joint torque and mechanical energy consumption were compared before and after a total of 5 sessions (2.5 weeks) of running. A total of 11 young healthy participants exhibited higher elastic energy storage in carbon plates in the fifth session compared to the first session, and lower power in the ankle joint. This suggests that a single training session may be insufficient to validate the efficiency effect of added joint stiffness, and the human body seems to increase the elastic energy stored in the assistive joint stiffness and its reutilization.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.269-276
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• 2018

The purpose of this study was to investigate the relationship between Grit and stress and college adjustment of nursing college students and to confirm the effect of nursing students' adaptation to college life. The study subjects were 145 students who agreed to participate in this study after completing at least one semester of clinical practice. The collected data were analyzed by SPSS 23.0 program using descriptive statistics, Pearson's correlation, Multiple regression analysis. There was a significant positive correlation between college life adaptation and grit (r=.17, p=.047) and a negative correlation between stress and university life (r=-.31, p<.001). Grit and stress had an explanatory power of 11.2% on adaptation to college life(F=9.98, p<.001). The results of this study suggest that it is necessary to improve nursing students' Grit level and to develop effective stress management programs for their adaptation to college life.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.1-7
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• 2020

This paper proposes a link adaptation method for Underwater Internet of Things (IoT), which reduces power consumption of sensor nodes and improves the throughput of network in underwater IoT network. Adaptive Modulation and Coding (AMC) technique is one of link adaptation methods. AMC uses the strong correlation between Signal Noise Rate (SNR) and Bit Error Rate (BER), but it is difficult to apply in underwater IoT as it is. Therefore, we propose the machine learning based AMC technique for underwater environments. The proposed Modulation Coding and Scheme (MCS) prediction model predicts transmission method to achieve target BER value in underwater channel environment. It is realistically difficult to apply the predicted transmission method in real underwater communication in reality. Thus, this paper uses the high accuracy BER prediction model to measure the performance of MCS prediction model. Consequently, the proposed AMC technique confirmed the applicability of machine learning by increase the probability of communication success.

• Journal of Digital Convergence
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• v.18 no.12
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• pp.469-479
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• 2020

This study was attemted to grasp the factors affecting the caring efficacy of senior nursing students. Data were collected from 173 nursing students at J university in G-do. Analysis was done using t-test, ANOVA, Pearson correlation coefficient, and Multiple regression with IBM SPSS WIN/25.0. Caring efficacy was positively correlated with clinical learning environment (r=.42, p<.001), field practice adaptation (r=.53, p<.001), nursing professionalism (r=.42, p<.001), and negatively correlated to clinical practice powerlessness (r=-.46, p<.001). The most influential factor on the subjects' caring efficacy was field practice adaptation (β=.330, p<.001), followed by nursing professionalism (β=.188, p=.005), clinical learning environment (β=.176, p=.015), introvert (β=-.146, p=.018), and extrovert (β=.134, p=.035). The explanatory power was 41.8%. Therefore, systematic nursing programs that can enhance caring efficacy are needed. Also, the following data can be utilized as basic data to help develop caring efficacy programs.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.186-193
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• 2000

EPS(Electric Power Steering) systems have many advantages over traditional hydraulic power steering systems in space efficiency engine efficiency and environmental compatibility. In this paper an EPS system control logic using a torque map is proposed. The main function of the EPS system is to reduce the steering torque exerted by a driver by assist of an electric motor. Vehcile speed steering torque and steering wheel angle are measured and fed back to the EPS control system where appropriate assist torque is generated to assist the operator's steering effort. Another capability of the EPS system for easy adaptation to different steering feels via simple tuning is demonstrated by the experiments. It will be also verified that the EPS system can also improve damping and return performance of the steering wheel by control of the assist motor.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.8
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• pp.1449-1455
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• 2010

The excitation control system of an emergency diesel generator is classified as a kind of safety-related system. Compared with other control systems in a power plant, this system is required to be more reliable and have better performance. In this paper, the digital multi-redundant excitation system for a diesel generator was proposed. The signal processing system of the proposed system makes high speed signal processing and arithmetic in excitation control possible. The improved soft start algorithm and multiple PI parameters adaptation considering the diesel generator characteristics were implemented in the proposed system. The developed system was applied to a nuclear power plant successfully.

• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.288-295
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• 2005

In this paper a new adaptive, decentralized excitation control scheme proposed to enhance the transient stability of multimachine power systems is extensively analyzed with respect to its robustness and disturbance attenuation. As shown in the paper, both robustness and disturbance attenuation can be effectively improved by suitably selecting the design parameters of the proposed controller. Particularly, some simple rules for the selection of the control gains and the adaptation parameters are extracted which, as it is proven, may be essential for the system performance. Simulation tests on a two generator infinite bus power system absolutely confirm the theoretical results.