• 전력전자학회논문지
• /
• 제23권5호
• /
• pp.359-365
• /
• 2018

This study introduces a model predictive control method for controlling a cascaded flying capacitor multilevel rectifier used as an AC-DC rectifier of a solid-state transformer for DC distribution systems. The proposed method reduces the number of states that need to be considered in model predictive control by separately controlling input current, output DC link voltage, and flying capacitor voltage. Thus, calculation time is shortened to facilitate the level expansion of the cascaded flying capacitor multilevel rectifier. The selection of weighting factors did not present difficulties because the weighting factors in the cost function of the conventional model predictive control are not used. The effectiveness of the proposed method is verified through computer simulation using powersim and experiment.

• 지역사회간호학회지
• /
• 제20권3호
• /
• pp.381-389
• /
• 2009

Purpose: The study was to explore the level of low back pain and characteristic factors influencing low back pain (LBP) and mental health during pregnancy. Methods: The subjects were a total of 383 healthy pregnant women in S City and K-Do. Data were analyzed using descriptive statistics, t-test, ANOVA, and Pearson's correlation. Results: 82.5% of the pregnant women answered the existence of LBP and 19.7% of them had high LBP. The preferred method of controlling LBP was 'Just endure'(42.3%). There were significant differences in pregnancy level (p<.05) and discomfort condition related to pregnancy (p<.01) according to low back pain. There were significant differences in pain intensity according to mental health. The correlation between pain level and pregnancy weeks (p<.001) and BMI in previous pregnancy (p<.001) was significant. The correlation between mental health and age was significant (p<.001). Conclusion: The majority of the pregnant women experienced LBP during pregnancy. However, they were not offered the best method of controlling the pain. Thus, for preventing LBP during pregnancy, we recommend regular exercises and BMI control.

• 대한간호학회지
• /
• 제45권1호
• /
• pp.14-24
• /
• 2015

Purpose: The purpose of this study was to measure the level of expectations regarding aging (ERA) and identify relationship between ERA and physical activity of middle aged adults. Methods: Participants were middle aged adults who resided in the community in three cities in Korea. Data were collected using questionnaires that contained items on individual characteristic, International Physical Activity Questionnaires (IPAQ), and behavior-specific cognitive factors including ERA-12. Hierarchical multiple regression was conducted to examine whether ERA would predict physical activity by controlling other factors. Results: The mean age of the participants was $51.1{\pm}6.9$ years. The mean score for ERA (possible range=0 to 100) was $40.04{\pm}14.31$. More than half of the participants (62.6%) were not engaged in health promoting physical activity. Gender, employment status and exercise confidence were associated with level of physical activity (F=7.14, p<.001, $R^2=.36$). After controlling for individual factors and behavior-specific cognitive factors, ERA was independently related to physical activity (F=7.19, p<.001, $R^2=.38$). Conclusion: The results demonstrate that individuals' belief about aging has effects on physical activity in Korean middle aged adults. Thus, nursing interventions which focused on ERA could help enhance physical activity in middle aged adults.

• 대한교통학회:학술대회논문집
• /
• 대한교통학회 1995년도 한-중 국제학술회의 발표논문
• /
• pp.69-76
• /
• 1995

"승차난", "행차난", "정차난"시세계각국재성시화화성시현대화발전 중필연회출현적일개공동적문제,단치리적방법각불진상동. 본문근거상해적실 천,제출료파영향도로교통용량화운행질량적각충인소,종공제교통출행적산생. 개선교통출행적분포, 합리선택출행적방식, 과학선택출행적로선여출행적시간, 대력가강교통관리화도로건설등칠개방면진행통주협조, 종합치리적교통계통관리 기출.병지출타시대도시교통주출곤경적일충투자소, 견효쾌적유효방법.

• 유통과학연구
• /
• 제15권4호
• /
• pp.5-13
• /
• 2017

Purpose - This research analyzes the effects of Korean family ownership characteristics on firm value. The positive and negative effects of family ownership on Korean firm value were analyzed. If negative effects are evident, this research explores the factors that cause a decrease in firm value. Research design, data, and methodology - The study examined a total of 5,743 companies listed on the Korea Exchange from the period 2002 to 2012 using a panel data regression analysis. Result - An empirical analysis suggests that Korean family ownership diminishes firm value. Korean family firm value has been reduced when controlling shareholders are participated in management and pursue excessive wages, or make the management entrenchment effects associated with ownership-control disparity. When the controlling shareholders of family firms have increasing control rights over the shareholders' general meeting and the directors' board, the agency costs associated with seeking increasing executive wages or private benefits reduce firm value. Conclusions - This study has significance because it reveals the negative effect of family ownership in Korea on firm value. These negative effects can be the result of agency problems from controlling family shareholders seeking excessive wages or ownership-control disparity.

• 한국공간정보시스템학회 논문지
• /
• 제8권2호
• /
• pp.1-11
• /
• 2006

This paper addresses a GIS (Geographic Information System) based system in order to reduce the rate of public transportation accidents occurring in Iranian roads network. Over the years, the road accidents are a major issue throughout the world. Today, particular consideration is given to those technologies which can lead to diminish on the number of critical incidents. One of the main factors resulting in accidents and fatalities rates growth is the speed violation of buses in Iranian road network. The conventional speed controlling approach in Iran based on the Tachograph which records vehicle's speed, time, and stoppage in the mechanical processing has many problems. Hence, this research is intended to design and implement a GIS-based system to manage road accident of Bus transportation system using offline tracking system. This was accomplished using a GIS-based technique that encompasses three steps. The first step is developing a GIS-based accident system. The second step includes designing and applying a tracking system inside 90 buses for recording Bus information for speed controlling. Lastly, by using mentioned system in police center, the illegal drivers' punishment would be considered properly. Overall, this system has been successfully applied in this work. Therefore, the police and transportation office are able to control and make policy to diminish the number of accident. It is anticipated that online tracking system through the Web GIS would be utilized In this system in the near future.

• 유통과학연구
• /
• 제19권10호
• /
• pp.65-74
• /
• 2021

Purpose: The purpose of this study is to identify the maximum organizational effectiveness of compensation systems in the distribution industry. It is to identify the relationship between structural compensation and organizational effectiveness. It also aims to clarify whether distributive justice plays as a controlling variable between two variables. Research design, data and methodology: This study was conducted on distribution industry employees. The questionnaire was collected through self-subscription. A total of 209 questionnaires were collected during the month of April 2021, of which 203 were used as valid samples. Results: Structural compensation have been shown to have a positive impact on two sub-factors of organizational effectiveness. In the verification of the controlling effect of distributive justice, perceived fairness has a control effect on the relationship between extrinsic compensation and organizational effectiveness but it does not show a controlling effect on the relationship between intrinsic compensation and organizational effectiveness. Conclusions: Structural compensation has a positive effect on organizational effectiveness. The distribution industry should aware of the compensation and the perceived fairness. The fairness of distribution plays a role in identifying the recognition of compensation and organizational feasibility, identifying motivations of employees, and mediating proper strategies to enhance job satisfaction.

• Journal of Preventive Medicine and Public Health
• /
• 제46권4호
• /
• pp.165-172
• /
• 2013

A noncommunicable disease (NCD) is a medical condition or disease that is by definition non-infectious and non-transmissible among people. Currently, NCDs are the leading causes of death and disease burden worldwide. The four main types of NCDs, including cardiovascular disease, cancer, chronic lung disease, and diabetes, result in more than 30 million deaths annually. To reduce the burden of NCDs on global health, current public health actions stress the importance of preventing, detecting, and correcting modifiable risk factors; controlling major modifiable risk factors has been shown to effectively reduce NCD mortality. The World Health Organization's World Health Report 2002 identified tobacco use, alcohol consumption, overweight, physical inactivity, high blood pressure, and high cholesterol as the most important risk factors for NCDs. Accordingly, the present report set out to review the prevalence and trends of these modifiable risk factors in the Korean population. Over the past few decades, we observed significant risk factor modifications of improved blood pressure control and decreased smoking rate. However, hypertension and cigarette smoking remained the most contributable factors of NCDs in the Korean population. Moreover, other major modifiable risk factors show no improvement or even worsened. The current status and trends in major modifiable risk factors reinforce the importance of prevention, detection, and treatment of risk factors in reducing the burden of NCDs on individuals and society.

• 한국자동차공학회논문집
• /
• 제21권5호
• /
• pp.130-135
• /
• 2013

Until now, passenger airbag design is based on the referred car design and many repetitive crash tests have been done to meet the crash performance. In this paper, it was suggested a new design process of passenger airbag. First, key performance factors were determined by analyzing the injury risk effectiveness of each performance factor. And it was made a relationship between injury risk and performance factor by using the response surface model. By using this one, it can be predicted the injury risk of head and neck. Predicted injury risk of optimal design was obtained through this injury risk prediction model and it was verified by FE analysis result within 18% error of head and 9% error of neck. It was shown that a target crash performance can be met by controlling the key performance factors only.

• 대한간호학회지
• /
• 제16권2호
• /
• pp.5-12
• /
• 1986

The purpose of this study was to identify the factors which influence the effectiveness of nursing organization in the hospital. The data were collected by employing Delphi technique in a series of three rounds from June 15, 1985 to January 31, 1986. In each round the responses to questionnaires were analyzed and the results were communicated back to the subjects. Finally consensed among subjects in identification of the 45 items which influence the effectiveness of nursing organization in the hospital. The 48 items were reduced to 6 factors and named; planning, organization and problem-solving, staffing and staff developing, supporting, evaluating-controlling and leading, and the number of items included for each factor were 14,14,8,5,3,2 and respectively. Among the 48 items, 2 items were not loaded on forementioned 6 factors because factor loading was below 0.3.