• Journal of Power Electronics
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• v.15 no.2
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• pp.567-575
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• 2015

An improvement in the current fed parallel resonant half bridge (CFPRHB) circuits used in fluorescent lamp electronic ballasts is provided in this paper. The CFPRHB belongs to the self-oscillating family which includes the current fed push-pull and series resonant inverters, most of which are used in instant-start applications. However, many failure modes are related to the bypass capacitor according to an analysis of failed samples. In this paper, the operating functions of the existing topology in the steady state are analyzed and the main root cause of failure modes has been found. Comparisons between the two topologies are conducted in terms of the voltage stress of the bypass capacitor as well as the thermal and performance of the ballasts to verify the advantages of the proposed topology. It is found that the improved topology is capable of enhancing the reliability and reducing the cost of products without having a negative influence on the system performance.

• Journal of Information Processing Systems
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• v.17 no.6
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• pp.1138-1156
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• 2021

Emotional semantics are the highest level of semantics that can be extracted from an image. Constructing a system that can automatically recognize the emotional semantics from images will be significant for marketing, smart healthcare, and deep human-computer interaction. To understand the direction of image emotion recognition as well as the general research methods, we summarize the current development trends and shed light on potential future research. The primary contributions of this paper are as follows. We investigate the color, texture, shape and contour features used for emotional semantics extraction. We establish two models that map images into emotional space and introduce in detail the various processes in the image emotional semantic recognition framework. We also discuss important datasets and useful applications in the field such as garment image and image retrieval. We conclude with a brief discussion about future research trends.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.449-455
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• 2023

This study aims to identify the importance of students career adaptability and analyze the mediating effect of career stress in the relationship between career adaptability and psychological well-being of Specialized Vocational High School students. Among Specialized High School, third-year students from Commercial High School in Gyenggi and Chungchenog regions were selected as the study subjects. The results of analyzing the structural relationship between career adaptability, career stress, and psychological well-being are as follows. First, the higher the career adaptability of high school students, the lower the career stress. Second, the lower the career stress, the higher the students' psychological well-being. Third, there was no direct effect between career adaptability and psychological well-being.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7A
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• pp.682-687
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• 2010

The IEEE 802.15.4a specification targets the low-rate (LR) Impulse-radio (IR) ultra-wideband (UWB) system which is now widely applied in the WPANs considering rather short distance communications with low complexity and power consumption. The physical (PHY) layer uses concatenated coding with mixed binary phase-shift keying and binary pulse-position modulation (BPSK-BPPM), and direct sequence spreading with time hopping in order that both coherent and non-coherent receiver architectures are supported. In this paper, the performances of multiple access schemes compliant with IEEE 802.15.4a specification are investigated with energy detection receiver, which allow avoiding the complex channel estimation needed by a coherent receiver. However, the performance of energy detection receiver is severely degraded by multi-user interference (MUI), which largely diminishes one of the most fascinating advantages of UWB, namely robustness to MUI as well as the possibility to allow parallel transmissions. So as to improve the performance of multiple access schemes, we propose to apply the novel TH sequences as well as to increase the number of TH positions. The simulation results show that our novel multiple access schemes significantly improve the performance against MUI.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.12
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• pp.2355-2373
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• 2011

Vision-based vehicle detector systems are becoming increasingly important in ITS applications. Real-time operation, robustness, precision, accurate estimation of traffic parameters, and ease of setup are important features to be considered in developing such systems. Further, accurate vehicle detection is difficult in varied complex traffic environments. These environments include changes in weather as well as challenging traffic conditions, such as shadow effects and jams. To meet real-time requirements, the proposed system first applies a color background to extract moving objects, which are then tracked by considering their relative distances and directions. To achieve robustness and precision, the color background is regularly updated by the proposed algorithm to overcome luminance variations. This paper also proposes a scheme of feedback compensation to resolve background convergence errors, which occur when vehicles temporarily park on the roadside while the background image is being converged. Next, vehicle occlusion is resolved using the proposed prior split approach and through reasoning for rule-based tracking. This approach can automatically detect straight lanes. Following this step, trajectories are applied to derive traffic parameters; finally, to facilitate easy setup, we propose a means to automate the setting of the system parameters. Experimental results show that the system can operate well under various complex traffic conditions in real time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.392-401
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• 2010

The purpose of the present study was intended to assess psycosocial stress of male researchers working in a Research Institute, and to reveal the relationship between psycosocial stress and coronary risk factors. Data were obtained from 356 male researchers who underwent health package check-up at the health promotion center of a university hospital from May to June 2007, using by self-administered questionnaire & health check-up. For psycosocial stress, we used the questionnaire with 18 items developed as Psychosocial Well-bing Index(PWI). For coronary risk factors, systolic and diastolic blood pressure(SBP, DBP), triglyceride(TG), total cholesterol(TC), high and low density lipoprotein cholesterol(HDL, LDL), fasting blood sugar(FBS) and % fat rate were measured. As a results, the level of psycosocial stress is influenced by socio-demographic characteristics, job-related characteristics and health-related behaviors. Especially, it was found to have the inter-relational effects that the higher the blood pressure, the higher the level of psycosocial stress.

• Structural Engineering and Mechanics
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• v.49 no.1
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• pp.111-128
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• 2014

The stochastic response surface method (SRSM) and the response surface method (RSM) are often used for structural reliability analysis, especially for reliability problems with implicit performance functions. This paper aims to compare these two methods in terms of fitting the performance function, accuracy and efficiency in estimating probability of failure as well as statistical moments of system output response. The computational procedures of two response surface methods are briefly introduced first. Then their capabilities are demonstrated and compared in detail through two examples. The results indicate that the probability of failure mainly reflects the accuracy of the response surface function (RSF) fitting the performance function in the vicinity of the design point, while the statistical moments of system output response reflect the accuracy of the RSF fitting the performance function in the entire space. In addition, the performance function can be well fitted by the SRSM with an optimal order polynomial chaos expansion both in the entire physical and in the independent standard normal spaces. However, it can be only well fitted by the RSM in the vicinity of the design point. For reliability problems involving random variables with approximate normal distributions, such as normal, lognormal, and Gumbel Max distributions, both the probability of failure and statistical moments of system output response can be accurately estimated by the SRSM, whereas the RSM can only produce the probability of failure with a reasonable accuracy.

• Journal of Korea Entertainment Industry Association
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• v.13 no.7
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• pp.321-346
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• 2019

The cycle of human life has a limited time to death. Everyone cannot help but think how to live in the limited time and then they try to reach toward their happiness. Their pursuit for the happiness gives rise to the new trend called 'Well-bing'. Generally speaking, it means to eat well, to feel their own satisfaction with their lives and to spend a time on doing what they want to do. However, considering their current lives which are tough and harsh, it could be impossible for them to accomplish the well-being stated above. From this point, it is natural to think what real well-being means. Its real meaning would be understood by identifying its cause if well-being is the way to happiness. Based on the thesis stated above, let me look into the desire of human being. It has both side; it should be eliminated or overcome as a deficiency and disability in human life while it could be an driving force to let the human being keep their lives. They can find the real meaning of well-being and their happiness can be realized through the control of their desires. Above all, according to the control for them, they can accomplish their happiness or fail to do it. The trend of well-being can be kept in our culture when moral value is reflected to the well-being. Finally, it orients to the purpose of happiness. It also means that everyone shares moral and positive value one another in the process of challenge to achieve their goals. In order to realize it, they should be satisfied with their current situation and have a balance with everything related to themselves.

• Korean Journal of Childcare and Education
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• v.6 no.2
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• pp.155-173
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• 2010

The purpose of this study was to find factors affecting the psychological well-being of married working women in Seoul. For this purpose, survey data form 332 employed married women residing in Seoul are used to evaluate the relative effects of Psychological well-being of married working women. Survey questions included demographic information, housework and child-rearing related variables, work related variables, variables related with social support systems, items on child care services for the preschoolers, and psychological well-being of married working women. The major findings were as follows: 1) The psychological well-being of married working women score is 36.14(mean score is 32). The difference between the psychological well-being of married working women varied this according to socio-demographic variables: educational level, income level, spouse's support, occupation, and job satisfaction. 2) The factors that affected psychological well-bing were amount of household labor by husband, job satisfaction, socio-support systems, and educare service satisfaction. 3) The factor that had the most significant impact on the psychological well-being of married working women is job satisfaction. It is suggested to utilize the Employment Assistant Program to establish friendly working environment for married women.

• Korean Journal of Culture and Social Issue
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• v.21 no.4
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• pp.595-615
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• 2015

This study aims to develop well-being enhancement program for the female elderly living alone, and examine its effects. The program was structured by exploring the meaning of life and happiness with focused on self-disclosure, dealing with regret and resentment, forgiveness, gratitude, and resilience. At first, pilot program was applied to 6 female elderly living alone for predicting the effects and modified the program. For verification of the program effect, 11 female elderly living alone were assigned to developed well-being enhancement program, also 11 female elderly living alone were assigned to comparison group who participate in activity-focused program, and 12 female elderly living alone were assigned to control group. Results indicated that regret for interpersonal relations and resentment of the female elderly living alone who participate in well-being enhancement program were reduced after participating the program, while their self-disclosure increased. The female elderly living alone who participate in well-being enhancement program showed lowered level of anxiety, loneliness, and awareness of aging, which were factors of well-bing in senescence. Moreover, their level of negative emotion was decreased, and life satisfaction, positive emotion, and happiness were increased after participating the program. But, all of those enhancement were not found in control group as well as comparison group. These results suggest that well-being enhancement program for the female elderly living alone developed in this study could be utilized in various settings.