• Title/Summary/Keyword: Variance of Analysis

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Determination of Incentive Level of Direct Load Control using Monte Carlo Simulation with Variance Reduction Technique (몬테카를로 시뮬레이션을 이용한 직접부하제어의 제어지원금 산정)

  • Jeong Yun Won;Park Jong Bae;Shin Joong Rin;Chae Myung Suk
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.666-670
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    • 2004
  • This paper presents a new approach for determining an accurate incentive levels of Direct Load Control (DLC) program using sequential Monte Carlo Simulation (MCS) techniques. The economic analysis of DLC resources needs to identify the hourly-by-hourly expected energy-not-served resulting from the random outage characteristics of generators as well as to reflect the availability and duration of DLC resources, which results the computational explosion. Therefore, the conventional methods are based on the scenario approaches to reduce the computation time as well as to avoid the complexity of economic studies. In this paper, we have developed a new technique based on the sequential MCS to evaluate the required expected load control amount in each hour and to decide the incentive level satisfying the economic constraints. And also the proposed approach has been considered multi-state as well as two-state of the generating units. In addition, we have applied the variance reduction technique to enhance the efficiency of the simulation. To show the efficiency and effectiveness of the suggested method the numerical studies have been performed for the modified IEEE reliability test system.

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Effect of Incivility, Resilience, and Social Support Experienced by Nursing Students on Burnout in Clinical Practice (간호대학생이 임상실습에서 경험하는 무례함, 극복력, 사회적 지지가 소진에 미치는 영향)

  • Lee, Eun Jung;Sung, Mi-Hae;Ahn, Hye-Kyong;Kim, Yun Ah
    • Women's Health Nursing
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    • v.25 no.1
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    • pp.86-98
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    • 2019
  • Purpose: The purpose of the study was to determine effect of incivility, resilience, and social support experienced by nursing students on burnout in clinical practice. Methods: Subjects were 140 nursing students who agreed to participate in this study. Collected data were analyzed using descriptive statistics, t-test, analysis of variance, Pearson's correlation and stepwise multiple regression with SPSS WIN 23.0 program. Results: Burnout showed significantly positive correlation with incivility but significantly negative correlations with resilience and social support. Factors affecting burnout were satisfaction with major-dissatisfaction, satisfaction with major-average, social support, grade, and relationship with peers. Satisfaction with major (dissatisfaction) had the greatest effect on burnout, explaining 41% of the total variance. Conclusion: According to this study, dissatisfaction with major was identified as the most significant factor influencing burnout of nursing students in clinical practice. Therefore, it is important to develop and implement programs that can reduce dissatisfaction with major and increase social support and relationship with peers in order to lower burnout of nursing students. In addition, a systemic management of fourth-grade students with a high level of clinical practice is necessary to reduce the level of clinical practice. The authors declared no conflict of interest.

A Study on Unfolding Asymmetric Volatility: A Case Study of National Stock Exchange in India

  • SAMINENI, Ravi Kumar;PUPPALA, Raja Babu;KULAPATHI, Syamsundar;MADAPATHI, Shiva Kumar
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.4
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    • pp.857-861
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    • 2021
  • The study aims to find the asymmetric effect in National Stock Exchange in which the Nifty50 is considered as proxy for NSE. A return can be stated as the change in value of a security over a certain time period. Volatility is the rate of change in security value. It is an arithmetical assessment of the dispersion of yields of security prices. Stock prices are extremely unpredictable and make the investment in equities risky. Predicting volatility and modeling are the most profuse areas to explore. The current study describes the association between two variables, namely, stock yields and volatility in equity market in India. The volatility is measured by employing asymmetric GARCH technique, i.e., the EGARCH (1,1) tool, which was used in building the study. The closing prices of Nifty on day-to-day basis were used for analysis from the period 2011 to 2020 with 2,478 observations in the study. The model arrests the lopsided volatility during the mentioned period. The outcome of asymmetric GARCH model revealed the subsistence of leverage effect in the index and confirms the impact of conditional variance as well. Furthermore, the EGARCH technique was evidenced to be apt in seizure of unsymmetrical volatility.

Structural Equation Modeling on Healthy Menopausal Transition (건강한 폐경이행 구조모형)

  • Hong, Eunyoung;Kang, Young Sil
    • Journal of Korean Academy of Nursing
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    • v.45 no.1
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    • pp.64-75
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    • 2015
  • Purpose: This study was designed to construct and test structural equation modeling on healthy menopausal transition in middle-aged women in order to identify variables affecting healthy menopausal transition. Methods: Participants, 276 women, 45 to 60 years of age, with menopausal symptom score higher than 5 on the Korean version of Menopause Rating Scale, were recruited in three cities and one county of Gyeongnam Province. Research data were collected via questionnaires and analysed using SPSS version 18.0 and AMOS version 20.0. Results: After confirmatory factor analysis, one of the observed variables was excluded due to relatively low factor loading. The model fit indices for the hypothetical model were suitable for the recommended level: GFI=.93, CFI=.92, RMSEA=.05. Self-efficacy, self-differentiation, and menopausal symptoms explained 67.7% of variance in menopausal transition, and self-differentiation was the most influential factor for menopausal transition. Self efficacy and menopausal symptoms explained 9.6% of variance in menopausal management, although "menopausal symptoms" was not significant. Conclusion: These results suggest that nursing interventions to improve self-differentiation, self efficacy, menopausal management and decrease menopausal symptoms are critical for healthy menopausal transition in middle-aged women. Continued development of a variety of community-based nursing interventions to facilitate healthy menopausal transition is suggested.

Gender Differences in Factors Influencing The Framingham Risk Score-Coronary Heart Disease by BMI (남녀 체질량지수에 따른 관상동맥질환위험도(Framingham Risk Score-Coronary Heart Disease) 영향요인)

  • Park, Kwang-Ok;Seo, Ji-Yeong
    • Research in Community and Public Health Nursing
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    • v.25 no.4
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    • pp.248-258
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    • 2014
  • Purpose: This study was to investigate factors influencing the Framingham risk score-Coronary heart disease (FRS-CHD) according to gender and body mass index (BMI) of adults who participated in the 5th Korea National Health and Nutrition Examination Survey (KNHANES V-3). Methods: This study used a cross-sectional design with secondary analysis with KNHANES V-3. The FRS-CHD scores were measured with ages, sex, blood pressure, cholesterol, high density lipoprotein, smoking, and diabetes mellitus. With demographic characteristics, family history of ischemic heart disease, types (intensity) and days of physical activities, perceived stress, drinking, menopause (in female), and BMI scores were measured. The data were analyzed with descriptive statistics, Pearson's correlation coefficients, and multiple regressions. Results: FRS-CHD was significantly associated with types (intensity) and days of physical activities, educational level, occupation, and marital status, explaining 19.1~76.8% of the variance in men. FRS-CHD was significantly associated with types (intensity) and days of physical activities, menopause, and education level, explaining 55.0~59.5% of the variance in women. Conclusion: Factors influencing FRS-CHD were significantly different according to gender and BMI. To reduce the risk of coronary artery disease, it is necessary to develop gender-specific physical activity programs according to BMI.

Analysis for Thermal Distribution of Low-voltage Condenser by the Variance of Voltage & Frequency (전압 및 주파수 변화에 따른 저압 콘덴서 열 분포 해석)

  • Kim, Jong-Gyeum
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.4
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    • pp.43-49
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    • 2010
  • Power capacitor has been used to compensate for the low power factor of inductive load and to reduce harmonics generated by the power conversion device with reactor. The increase of voltage and current and thermal generation are extremely hard on the life of condenser. Current will be increased, provided that voltage and frequency of condenser increase also. The increase of voltage and frequency justly extends thermal generation. Both act on insulation stress and can afford to premature fault In this paper, we measured thermal distribution of condenser with infrared rays camera in case of variance of voltage and frequency. We were assured that the increase of voltage and frequency produces high heat and exceedingly shortens the life of condenser.

Disaster Preparation of Visiting Nurses in Public Health Centers (보건소 방문간호사의 재난대비 및 재난간호핵심능력 영향요인)

  • Uhm, Dongchoon;Park, Youngim;Oh, Hyunjin
    • The Journal of Korean Academic Society of Nursing Education
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    • v.22 no.2
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    • pp.240-249
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    • 2016
  • Purpose: The purpose of this study was to identify the factors influencing personal disaster preparation and disaster nursing core competency among visiting nurses in public health centers. Methods: A descriptive survey study was adopted. A convenience sample was taken from 277 subjects in three regions. Data were analyzed by descriptive statistics, t-test, ANOVA, correlation, Pearson correlation coefficient and multiple regression. Results: The mean personal disaster preparation and disaster nursing core competency scores were 11.13 and 76.87, respectively. Personal disaster preparation was statistically significant by experience of disaster victims and disaster management guideline. Disaster nursing core competency was statistically significant by participation in future disaster recovery. As a result of multiple regression analysis, personal disaster preparation accounted for 14.9 of the variance by experience of disaster victims and disaster management guidelines; disaster nursing core competency accounted for 8.9 of the variance by perception of disaster nursing. Conclusion: Although visiting nurses are ill-prepared for disaster, global natural and man-made disasters can occur regardless of time and place. Disaster education and training should therefore be included in nurses' fundamental education.

Effects of Perception of Marital Conflict and Child Rearing Attitude on Child Abuse and Emotional Maladjustment Behavior in Children (아동이 지각한 부모의 부부갈등, 양육태도가 학대경험과 정서적 부적응 행동에 미치는 영향)

  • Moon, Young-Sook
    • Child Health Nursing Research
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    • v.17 no.1
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    • pp.22-30
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    • 2011
  • Purpose: The purpose of this study was to examine the effects of the perception of marital conflict and child rearing attitudes on abuse experience and emotional maladjustment behavior in children. Methods: Data were collected from May 25 to June 5, 2009. A questionnaire survey was used with 320 elementary school students. Data were analyzed using Pearson correlation coefficients and multiple regression analysis. Results: For effects of perception of marital conflict and child rearing attitude on abuse experience among these children, authoritarian controlling disposition, affectionate disposition and marital conflict had a significant impact on their overall abuse experience. These variables were predictors of child abuse and accounted for 30.6% of the variance. For effects of perception of marital conflict, child rearing attitude and abuse experience on emotional maladjustment behavior among children, there was a significant influence for marital conflict, neglect, emotional abuse and authoritarian controlling disposition. These variables were predictors of emotional maladjustment behavior and accounted for 21.5% of the variance. Conclusion: The results indicate that marital conflict and child rearing attitude are two major variables affecting children’s abuse experience and emotional maladjustment behavior.

Factors Influencing Compassion Fatigue among Hospice and Palliative Care Unit Nurses

  • Cho, Eun-Ju;Cho, Hun Ha
    • Journal of Hospice and Palliative Care
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    • v.24 no.1
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    • pp.13-25
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    • 2021
  • Purpose: This descriptive study aimed to explore nursing workplace spirituality, end-of-life care stress, and resilience as factors influencing compassion fatigue among nurses working in hospice and palliative care units. Methods: Data were collected using a self-report questionnaire completed by 146 nurses at 14 hospice and palliative care institutions across South Korea who had worked in a hospice and palliative care institution for at least 6 months and had experience providing end-of-life care. Data were collected from February 25, 2019 to April 12, 2019, and analyzed using SPSS for Windows version 18.0. As appropriate, descriptive statistics, the t-test, analysis of variance, the Scheffé test, Pearson correlation coefficients, and stepwise multiple regression were used. Results: The survey results showed that factors influencing compassion fatigue were resilience, subjective health status, current satisfaction with the hospice ward, and end-of-life care stress. Higher levels of resilience, a subjective health status of "healthy", high levels of current satisfaction with the hospice ward, and lower levels of end-of-life care stress were associated with lower levels of compassion fatigue, explaining 42.9% of the total variance. Conclusion: The results of this study suggest that resilience is an important factor mitigating compassion fatigue among nurses at hospice and palliative care institutions. Therefore, intervention programs should be developed to reduce compassion fatigue.

Estimation of Systolic Blood Pressure using PTTL (PTTL을 이용한 수축기 혈압추정)

  • Kil, Se-Kee;Kwan, Jang-Woo;Yoon, Kwang-Sub;Lee, Sang-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.6
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    • pp.1095-1101
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    • 2008
  • The desirable method to diagnose abnormal blood pressure is to measure and manage blood pressure continuously and regularly. However, the sphygmomanometers that are based on a cuff have faults in that they can not measure the blood pressure continuously and they cause an unpleasant feeling. Therefore, it is essential to develop a new measuring method that causes no pain and that can obtain blood pressure continuously without any unpleasant feeling. Thus, we propose here a regression method to estimate the systolic blood pressure by using the PTTL(pulse transit time on leg) with some body parameters which are chosen from the relational analysis with systolic blood pressure. The data we use to make the regression model were obtained in triplicate from each of 50 males who were from 18 to 35 years. And we made estimation experiments of blood pressure on 10 males who did not take part in the making the regression model. According to the results, the proposed method showed a mean error of 4.00 mmHg and the standard variance was 2.45 mmHg. When we comparing the results of the proposed method with the rule of American National Standards Institute of the Association of the Advancement of Medical Instruments(ANSI/AAMI), the results satisfied the rule of a mean error less than 5 mmHg and a standard variance less than 8 mmHg. Therefore we were able to validate the usefulness of the proposed method.