• Title/Summary/Keyword: equivalent normal standard deviation

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Analysis of the Mean and Standard Deviation due to the Change of the Probability Density Function on Tidal Elevation Data (조위의 확률밀도함수 변화에 따른 평균 및 표준편차 분석)

  • Cho, Hong-Yeon;Jeong, Shin-Taek;Lee, Khil-Ha;Kim, Tae-Heon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.22 no.4
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    • pp.279-285
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    • 2010
  • In the process of the probabilistic-based design on the coastal structures, the probability density function (pdf) of tidal elevation data is assumed as the normal distribution function. The pdf shape of tidal elevation data, however, is better-fitted to the double-peak normal distribution function and the equivalent mean and standard deviation (SD) estimation process based on the equivalent normal distribution is required. The equivalent mean and SD (equivalent parameters) are different with the mean and SD (normal parameters) estimated in the condition that the pdf of tidal elevation is normal distribution. In this study, the difference, i.e., estimation error, between equivalent parameters and normal parameters is compared and analysed. The difference is increased as the tidal elevation and its range are increased. The mean and SD differences in the condition of the tidal elevation is ${\pm}400cm$ are above 100 cm and about 80~100 cm, respectively, in Incheon station. Whereas, the mean and SD differences in the condition of the tidal elevation is ${\pm}60cm$ are very small values in the range of 2~4 cm, in Pohang station.

Effects of Qi Hand Reflexology on Autonomic Nervous System Activity and Physical Resistance to Stress in Inpatients (기 손 반사요법이 입원환자의 자율신경계 활성도와 스트레스 저항도에 미치는 영향)

  • Oh, Sei-Young;Park, Ok-Soon;Woo, Myung-Yi
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.17 no.4
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    • pp.531-538
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    • 2010
  • Purpose: This study was done to identify the effects of Qi hand reflexology on autonomic nerve activity in patients admitted to hospital. Method: A non-equivalent control group and quasi-experimental research with pre/post test design were used and 59 patients on a medical ward were assigned to either the experimental group (32) or the control group (27). The study variables included vital signs, autonomic nerve activities (ALF (absolute low frequency), AHF (absolute high frequency), nLF (normalized low frequency), nHF (normalized high frequency), SDNN (standard deviation of all normal-normal intervals)) and were evaluated using the QECG-3 system. The experimental group was treated with Qi hand reflexology for 10 minutes per day, for 3days. Results: Skin temperature and systolic blood pressure in the experimental decreased with treatment. ALF, AHF and SDNN for the experimental group increased with regulating proportion (nLF: nHF=6:4) and a significant difference between the groups was observed. Conclusion: The results indicated that application of Qi hand reflexology for patients in the hospital is effective in regulating the autonomic nervous system activation. Implication of finding should be useful for future research.

The Mean-VaR Framework and the Optimal Portfolio Choice (평균-VaR 기준과 최적 포트폴리오 선택)

  • Ku, Bon-Il;Eom, Young-Ho;Choo, Youn-Wook
    • The Korean Journal of Financial Management
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    • v.26 no.1
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    • pp.165-188
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    • 2009
  • This paper has suggested the methodology for the frontier portfolios and the optimal portfolio under the mean-VaR framework, not assuming the normal distribution and considering the investor's preferences for the higher moments of return distributions. It suggested the grid and rank approach which did not need an assumption about return distributions to find the frontier portfolios. And the optimal portfolio was selected using the utility function that considered the 3rd and the 4th moments. For the application of the methodology, weekly returns of the developed countries index, the emerging market index and the KOSPI index were used. After the frontier portfolios of the mean-variance framework and the mean-VaR framework were selected, the optimal portfolios of each framework were compared. This application compared not only the difference of the standard deviation but also the difference of the utility level and the certainty equivalent expressed by weekly expected returns. In order to verify statistical significances about the differences between the mean-VaR and the mean-variance, this paper presented the statistics which were obtained by the historical simulation method using the bootstrapping. The results showed that an investor under the mean-VaR framework had a tendency to select the optimal portfolio which has bigger standard deviation, comparing to an investor under the mean-variance framework. In addition, the more risk averse an investor is, the bigger utility level and certainty equivalent he achieves under the mean-VaR framework. However, the difference between the two frameworks were not significant in statistical as well as economic criterion.

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The Effect of Dance Therapy on Pulmonary and Cognitive Function in the Elderly (무용요법이 노인의 폐기능과 인지기능에 미치는 효과)

  • 이영란;유숙자
    • Journal of Korean Academy of Nursing
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    • v.29 no.6
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    • pp.1273-1283
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    • 1999
  • This study was done to explore the effects of dance therapy on pulmonary and cognitive functions in the elderly. The design of this study was a non-equivalent pre-post test experiment. The subjects consisted of elderly persons living in a facility located in Kyoungi-Do. Fifty eight subjects had normal cognition, sensory function and resting blood pressure. They underwent tests of pulmonary and cognitive function as baseline data before dance therapy, and at 6th week and at the end of 12nd week after following dance therapy. Twenty seven elderly persons were assigned to the experimental group and participated with the dance therapy. This therapy was based on the Marian Chace's dance therapy and Korean traditional dance with music. The dance therapy consisted of 50 minutes session, 3 times a week for 12 weeks. One session consisted of warming-up, expression, catharsis, sharing and closing stage. the intensity of the dance therapy was at the 40% of age-adjusted maximum heart rates. Data were analyzed with mean, standard deviation, Chi-square test, unpaired t-test, repeated measures ANOVA, and Bonferroni multiple regression using SAS program. The results were as follows : 1. Pulmonary function(forced expiratory volume at one second and forced vital capacity) of the experimental subjects significantly increased over time more than that of the control subjects. 2. The experimental group had significantly higher score for pulmonary function than the control group at the 12nd week after dance therapy. 3. Cognitive function of the experimental subjects significantly increased over time more than that of the control subjects. 4. The experimental group had significantly higher score for cognitive function than the control group at the 6th week and 12nd week after dance therapy. The findings showed the dance therapy could be effective in improving the pulmonary and cognitive function of the elderly.

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The Effect of Dance Therapy on Physical and Psychological Characteristics in The Elderly (무용요법이 노인의 신체적.심리적 특성에 미치는 효과)

  • 이영란
    • Journal of Korean Academy of Nursing
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    • v.29 no.2
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    • pp.429-444
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    • 1999
  • This study was performed to explore the effects of a dance therapy on physical and psychological characteristics in the elderly. The design of this study was a non-equivalent pre-post test experiment. The subjects consisted of elderly persons living in a facility located in Suweon and Bucheon. Fifty eight subjects, aged between 65 and 93 years who had normal cognition, sensory function, balance, and resting blood pressure. They underwent tests of balance, flexibility, muscle strength, depression, and anxiety as baseline data before dance therapy, and at 6th week and at the end of the 12nd week after following dance therapy. Twenty seven elderly persons were assigned to the experimental group and participated with the dance therapy between April and July, 1998. The dance therapy was developed by the author with the help of a dance therapist and a physiatrist. This therapy was based on the Marian Chace's dance therapy and Korean traditional dance with music. The dance therapy consists of 50 minutes session, 3 times a week for 12 weeks. One session was consisted of warming-up, expression, catharsis, sharing, and closing stage. The intensity of the dance therapy was at the 40 % of age-adjusted maximum heart rates. Data were analysed with mead standard deviation, Chi-square test, unpaired t-test, repeated measures ANOVA, and Bonferroni multiple regression using SAS program. 1. The results related to the physical characteristics were as follows : 1) The balance (standing on one leg, walking on the balancing bar), flexibility and muscle strength (knee extensor, knee flexor, ankle plantarflexor and dorsiflexor) of the experimental subjects significantly increased over time mere than that of the control subjects. 2) The experimental group had significantly higher score for balance, flexibility, muscle strength of knee extensor, and knee flexor than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly higher score for muscle strength of ankle dorsiflexor and plantarflexor than the control group at the 6th week and the 12nd week after dance therapy. 2. The results related to psychological characteristics were as follows : 1) Scores of Geriatric Depression Scale, Hamilton Depression Rating Scale, and Zung's Self-rating Anxiety Scale of the experimental group were significantly decreased over time more than that of the control group. 2) The experimental group had significantly lower score for depression than the control group at the 12nd week after dance therapy. 3) The experimental group had significantly lower score for anxiety than the control group at the 6th week and the 12nd week after dance therapy. The findings showed that the dance therapy could be effective in improving the balances, flexibility, and muscle strength of lower limb, and effective in decreasing the depression and anxiety of the elderly. Additional merits of the dance therapy would be inexpensiveness, easy accessibility, and increasing interpersonal relationship. It can be suggested that the dance therapy is effective in the health promotion of the elderly.

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The Effect of Aerobic Rhythmical Exercise Program on Physical Fitness, Self-efficacy and Quality of Life in Elderly (유산소 리듬 운동프로그램이 노인의 체력, 자기효능감 및 삶의 질에 미치는 효과)

  • Kim Jong Hwa;Park Young Sook
    • Journal of Korean Public Health Nursing
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    • v.14 no.1
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    • pp.12-25
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    • 2000
  • The purpose of this study was to determine the effects of aerobic rhythmical exercise program on $VO_2$ max, leg strength, grip strength, flexibility, exercise self-efficacy and quality of life in elderly. This quai-experimental study was designed as a non-equivalent control group pretest-posttest study. 36 subjects, aged between 65 and 73 years who have normal cognition. sensory function and cerebellum function participated in this study. 19 experimental group subjects participated aerobic rhythmical exercise program. Aerobic rhythmical exercise program was developed on the basis of calisthenics, stretching, aerobic exercise, Korean traditional dance and music by the author. The program consisted of approximately 1 hours of exercise, 3 times a week for 9 weeks. During 1 hours workout, there were 15 minutes of warm-up dancing, 35 minutes of conditioning dance and 10 minutes of cool-down dancing. The intensity for the conditioning phase was between $40\%\;and\;60\%$ of age adiusted maximum heart rates. The $VO_2$ max, grip strength, leg strength, flexibility, exercise self-efficacy and quality of life were measured prior to and following the experimental treatment. Data were analyzed with $x^2-test$, t-test, mean, standard deviation. percentage of change and ANCOVA test using SAS program. Results were obtained as follows. 1. The $VO_2$ max of the experimental group were significantly lower than those of the control group following the aerobic rhythmical exercise program(F=7.76, p=0.008). 2. The grip strength of the experimental group were significantly lower than those of the control group following the aerobic rhythmical exercise program(F=4.61, p=0.039). 3. The leg strength of the experimental group were significantly lower than those of the control group following the aerobic rhythmical exercise program(F=9.29, p=0.000). 4. The was no significantly difference of flexibility between experimental and control group 5. The self-efficacy of the experimental group were significantly lower than those of the control group following the aerobic rhythmical exercise program(F=43.40, p=0.000). 6. The quality of life of the experimental group were significantly lower than those of the control group following the aerobic rhythmical exercise program(F=8.91. p=0.005). The results suggest that aerobic rhythmical exercise program can improve $VO_2$ max, grip strength. leg strength. exercise self-efficacy and quality of life elderly. Thus. aerobic rhythmical exercise program was a useful nursing intervention for elderly.

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