• Title/Summary/Keyword: Mean difference test

Search Result 2,199, Processing Time 0.039 seconds

Change of Knowledge and Attitude toward AIDS of Soldier through Health Education (AIDS에 대한 보건교육을 통한 일부 사병의 지식 및 태도변화)

  • 홍순이;정문숙
    • Korean Journal of Health Education and Promotion
    • /
    • v.11 no.1
    • /
    • pp.3-15
    • /
    • 1994
  • This study was conducted to investigate changes of knowledge and attitude toward AIDS of soldier through health education. The sample was selected with and experimental group(160 persons who were received health education group) and control group(160 persons who were not received), 20-21 years of age from 320 persons(soldier) who were between in a certain base located in Kyung Gi province. The data was collected from 24th Feb. to 21st April 1993. By questionnaires before and post test for education process about 4 weeks(pre and post test). The results of this study were as follows ; Of 320 soldiers 66.6% had received health education on sex before attending in base, 58.8%(94 persons) of experimental group and 58.1%(93 persons) had experience with sexual intercourse. In characteristics related to sexual intercourse experience, age of first sexual intercourse for experimental group was 19 in highest percentage as 30.0%, 18 in control group, 64.9% of experimental group and 61.4% of control group answered no use condom during sexual intercourse. About the reasons why use condom 51.5% of experimental group answered to prevention of VD and 44.4% of control group answered to prevention of partner's pregnancy in the highest percentage. There was no significant difference between mean score of knowledge level of experimental group and mean score of control group in pre-test. There was significant difference between mean score(15.23) of experimental group and mean score(12.98) of control group(p<0.01) in post-test. The attitude level in pre, post education was mean score 11. There was significant difference between mean score(9.04) of experimental group in pre-test and mean score(9.39) in post education(p<0.05), There was also significant difference between mean score(9.16) of control group in pre-test and mean score(9.60) in post-test(p<0.05), Mean score of perceived susceptability level of experimental group decreased from mean score 2.84 in pre-test to 2.66 in post-test, there was no significant difference between mean score of pre-test and that of post-test in 2 group. There was no significant difference between mean scores of perceived severity of experimental group in pre-test and that in post-test and there was no significant difference between mean score of perceived severity of control group in pre-test and post-test. There was no significant differences between mean scores of perceived benefits to act health behavior of experimental group or control group and pre-test and post-test.

  • PDF

Tests for Normal Mean Change with the Mean Difference

  • Kim, Jaehee;Yun, Pilkyoung
    • Communications for Statistical Applications and Methods
    • /
    • v.10 no.2
    • /
    • pp.353-359
    • /
    • 2003
  • This paper deals with the problem of testing mean change with one change-point with the normal random variables. We propose a test with the mean difference for change in a location parameter. A power comparison study of various change-point test statistics is performed via Monte Carlo simulation with S-plus software.

Scene Change Detection using the Automated Threshold Estimation Algorithm

  • Ko Kyong-Cheol;Rhee Yang-Won
    • The Journal of Information Systems
    • /
    • v.14 no.3
    • /
    • pp.117-122
    • /
    • 2005
  • This paper presents a method for detecting scene changes in video sequences, in which the $chi^{2}$-test is modified by imposing weights according to NTSC standard. To automatically determine threshold values for scene change detection, the proposed method utilizes the frame differences that are obtained by the weighted $chi^{2}$-test. In the first step, the mean and the standard deviation of the difference values are calculated, and then, we subtract the mean difference value from each difference value. In the next step, the same process is performed on the remained difference values, mean-subtracted frame differences, until the stopping criterion is satisfied. Finally, the threshold value for scene change detection is determined by the proposed automatic threshold estimation algorithm. The proposed method is tested on various video sources and, in the experimental results, it is shown that the proposed method is reliably estimates the thresholds and detects scene changes.

  • PDF

The Difference of Duration of Post-rotatory Nystagmus Test Between Normal Children and Children With Pervasive Developmental Disorder (비장애 아동과 전반적 발달장애 아동에서 회전 후 안구진탕 기간의 비교)

  • Kim, Jin-Mi;Song, Ji-Won;Hong, Eung-Kyoung;Kim, Sung-Hee;Kim, Kyeong-Mi
    • The Journal of Korean Academy of Sensory Integration
    • /
    • v.3 no.1
    • /
    • pp.1-11
    • /
    • 2005
  • Objective : The purpose of this study was to get the mean of duration of post-rotatory nystagmus test in normal children and to differentiate the duration of post-rotatory nystagmus test between normal children and children with pervasive developmental disorder. Method : 84 subjects were between 3 and 5 years of age and consisted of 64 normal children and 20 children with the pervasive developmental disorder. Analysis of the data was done by using t-test and ANOVA. Results : The results were as follows: 1. Range of duration of post-rotatory nyatagmus test in normal children was $5{\sim}22$second on left and $7{\sim}21$ second on right and the mean was 12.63 second on left and 12.59 second on right. 2. Range of duration of post-rotatory nystagmus test in children with the pervasive developmental disorder was $3{\sim}11$ second on both and the mean was 5.65 second on left and 5.60 second on right. 3. There was no significant difference between males and females with normal children in duration of post-rotatory nystagmus test. However, there was a significant difference of the mean duration between 3 and 5 years old normal group. 4. Children with pervasive developmental disorder significantly have relatively lower duration than the duration of post-rotatory nystagmus test of normal children. Conclusions : The results of the study showed significant difference between normal children and children with pervasive developmental disorder in duration of post-rotatory nystagmus test and suggest that they could be applied to the baseline of clinical therapy.

  • PDF

A study on characteristics and physiological variables of chest pain induced by exercise test in angina suspected patients (협심증이 의심되는 환자에서 운동부하검사로 유발되는 흉통의 양상과 생리적 변인에 관한 연구)

  • Cho, Mi-Kyoung;Choe, Myoung-Ae
    • Journal of Korean Biological Nursing Science
    • /
    • v.2 no.2
    • /
    • pp.1-19
    • /
    • 2000
  • The purpose of this study was to identify the characteristics and physiological variables of chest pain induced by exercise test in angina suspected patients. The subjects of this study consisted of 28 inpatients and outpatients aged between 40 and 75 who underwent treadmill test at exercise testing laboratory of S-University from January 2000 to June 2000. Subjects were interviewed with questionnaire regarding sociodemography, the past health history and history related to chest pain before the exercise test. Subjects were interviewed with questionnaire concerning quality, intensity, duration of chest pain induced by walking on the treadmill(Marquette, U.S.A. 1992) according to Bruce protocol following exercise test. Systolic and diastolic blood pressure were measured before, during and after the test, heart rate was determined by ECG. The results of this study were as follows ; 1) Quality of chest pain induced by exercise test were feeling stiffness 19(67.9%), heavy 10(36.0%), exploded 9(32.1%), crushing, suffocating, tight 8(28.6%), stuffy, prickly 7(25.0%), burning 6(21.4%), clasp 5(17.9%), cleaved, tensed, piercing 3(10.7%), perfectly fitting, sore 2(7.1%), tearing, tingling, ticklish, heartburn 1(3.6%). 2) Mean score of VAS(intensity of pain) following exercise test was $5.79{\pm}2.27$ and mean duration of chest pain after the test was $7.83{\pm}5.31$ minutes. 3) Sites of chest-pain induced by exercise test were middle site 11(39.3%), left-chest 10(35.6%), right-chest 6(21.5%). Radiation site of chest-pain was neck(18.0%), right flank site 1(3.6%), left shoulder & arm 2(7.1%) and back 1(3.6%). 4) Symptoms other than chest-pain induced by exercise test were dyspnea 21(75.6%), perspiration 14(50.4%), fatigue 12(43.2%), leg-pain 11(39.6%), dizziness 7(25.2%) anxiety toward chest-pain 3(10.8%), thirst 2(7.1%), and palpation, headache and tingling sensation of hand and leg 1(3.6%). 5) Mean MET(intensity of exercise) during the exercise test was $7.64{\pm}2.57$ and mean RPE(rating of perceived exertion) was $15.89{\pm}2.36$. Mean duration of exercise was $6.79{\pm}2.88$. 6) correlation coefficients between RPE and VAS was 0.500(p=0.003), those between MET and VAS was 0.287(p=0.069) and those between either depression or elevation of ST segment and VAS was 0.236(p=0.114). 7) There was a significant difference in mean systolic pressure between before and after the test as $146.29{\pm}28.18mmHg$ and $177.96{\pm}28.82mmHg$(t=-5.640, p=0.000), a significant difference in mean diastolic blood pressure between before and after the test as $84.85{\pm}15.07mmHg$ and $88.89{\pm}13.72mmHg$(t=-2.082, p=0.047), and there was a significant difference in mean heart-rate between before and after the test as $81.89{\pm}12.22/min$ and $160.68{\pm}21.77/min$(t=-21.255, p=0.000).

  • PDF

Automatic Threshold-decision Algorithm using the Average and Standard Deviation (평균과 표준편차를 이용한 자동 임계치-결정 알고리즘)

  • Ko, Kyong-Cheol;Rhee, Yang-Won
    • The Journal of Korean Association of Computer Education
    • /
    • v.8 no.6
    • /
    • pp.103-111
    • /
    • 2005
  • This paper presents a novel automated threshold-decision algorithm that uses the mean and standard-deviation values obtained from the difference values of consecutive frames. At first, the calculation of difference values is obtained by the weighted ${\chi}^2$-test algorithm which was modified by joining color histogram to ${\chi}^2$-test algorithm. The weighted ${\chi}^2$-test algorithm can subdivide the difference values by imposing weights according to NTSC standard. In the first step, the proposed automatic threshold-decision algorithm calculates the mean and standard-deviation value from the total difference values, and then subtracts the mean value from the each difference values. In the next step, the same process is performed on the remained difference values, and lastly, the threshold is detected from the mean when the standard deviation has a maximum value. The proposed method is tested on various video sources and, in the experimental results, it is shown that the proposed method efficiently estimates the thresholds and reliably detects scene changes.

  • PDF

Thermal Stratification Effects Near an Interface by Horizontal Inflow of Cold Water in Thermal Storage Tank (냉수가 수평유입되는 열저장탱크의 중간 경계면 부근에서의 열성층 효과)

  • Hwang, Sung-Il;Pak, Ee-Tong
    • Solar Energy
    • /
    • v.8 no.2
    • /
    • pp.46-56
    • /
    • 1988
  • This investigation concerns thermal stratification of the water due to the temperature difference (${\Delta}T=T_{\infty}-T_i$) between the mean temperature of the water in the test tank (1m wide, 1m high, 2.1m long) and the temperature of the inflow water into the tank; flow rate of circulating water and height of the sink diffuser in the test tank. The additional objectives was to observe a stratification phenomena near an interface by measuring the velosities and the temperature difference and investigate an availabilities of the better effective hot water through establishing thermocline near an interface around the bottom of the tank. Following results were obtained through the experiments. 1. When the flow rate was constant and the temperature difference (${\Delta}T=T_{\infty}-T_i$) between the mean temperature of the flow in the test tank and the temperature of the inflow water increased by 5.6, 9.5, 13.5($^{\circ}C$), obtained the better effective advantage of hot water and the stress near an interface increased gradually. 2. When the ${\Delta}T=T_{\infty}-T_i$ was constant and flow rate increased by 4.0, 4.8, 6.4, 8.0 (LPM), obtained the better effective advent age of hot water and the mean stress near an interface increased gradually. 3. When the height of the sink diffuser was 25cm from tank bottom in comparison with 50cm, obtained the better effective advantage of hot water and the mean stress near an interface increased.

  • PDF

Determination of a Homogeneous Segment for Short-term Traffic Count Efficiency Using a Statistical Approach (통계적인 기법을 활용한 동질성구간에 따른 교통량 수시조사 효율화 연구)

  • Jung, YooSeok;Oh, JuSam
    • International Journal of Highway Engineering
    • /
    • v.17 no.4
    • /
    • pp.135-141
    • /
    • 2015
  • PURPOSES: This study has been conducted to determine a homogeneous segment and integration to improve the efficiency of short-term traffic count. We have also attempted to reduce the traffic monitoring budget. METHODS: Based on the statistical approach, a homogeneous segment in the same road section is determined. Statistical analysis using t-test, mean difference, and correlation coefficient are carried out for 10-year-long (2004-2013) short-term count traffic data and the MAPE of fresh data (2014) are evaluated. The correlation coefficient represents a trend in traffic count, while the mean difference and t-score represent an average traffic count. RESULTS : The statistical analysis suggests that the number of target segments varies with the criteria. The correlation coefficient of more than 30% of the adjacent segment is higher than 0.8. A mean difference of 36.2% and t-score of 19.5% for adjacent segments are below 20% and 2.8, respectively. According to the effectiveness analysis, the integration criteria of the mean difference have a higher effect as compared to the t-score criteria. Thus, the mean difference represents a traffic volume similarity. CONCLUSIONS : The integration of 47 road segments from 882 adjacent road segments indicate 8.87% of MAPE, which is within an acceptable range. It can reduce the traffic monitoring budget and increase the count to improve an accuracy of traffic volume estimation.

Level Satisfaction on Clinical Practice of Baccalaureate Nursing Students (간호학생의 임상실습 만족도에 관한 조사연구)

  • 이숙자
    • Journal of Korean Academy of Nursing
    • /
    • v.10 no.2
    • /
    • pp.41-52
    • /
    • 1980
  • As it Provides nursing students the opportunity for correlating principles and practice, clinical practice h s been considered as on of the most important part of nursing education. This study was desinged to measure the level of satisfaction in according with the conten. guidance environment. hours and the evaluation of clinical pracice. and to investigate the extent of influence of the variables have on the level of satisfaction. Two hundred and fifty-two nursing students from 9 baccalaureat programs in Seoule were randomly sampled. Instrument consists of forty questionaires. developed by the researcher, was used to gather data data from September 7 through 22, 1978. The level of satisfaction was measured by 5 Point rating scale(Likert-type). and level of significance were(t-test. F-test & X$^2$-test). -Results are as follow; 1. Level of satisfation according to the four variables ( class health. academic achievement, motives) revealed no significant difference. (P>.05). Hypothesis 1,2,3,4, are rejected. 2. Level of satisfaction according to the two variables (clinical instructor interpersonal relationship) revealed significant difference. (p<.01, p<.05), Hypothesis 5,6 are accepted. 3. Level of satisfaction of contents (mean score=3.02) revealed to be high.. 4. Level of satisfaction on guidance (mean Score=2.37), environment (mean score=2.59), hours (mean score=2.72) and evaluation (mean score=2.50) revealed to be low. 5. Level of satisfaction revealed to be low. (total mean satisfaction score =2.64).

  • PDF

A Nonparametric Test on Mean Difference of DEA Efficiency Estimates - Bootstrapping Approach- (DEA의 효율성 평균 차이에 대한 비모수적 검증-부트스트랩 접근법-)

  • 민재형;김진한
    • Journal of the Korean Operations Research and Management Science Society
    • /
    • v.24 no.2
    • /
    • pp.53-68
    • /
    • 1999
  • This paper presents a nonparametric method to test if the mean difference of DEA efficiency estimates between two groups statistically exists. A proposed method employs a bootstrapping approach to generation BCC efficiency estimates through Monte Carlo simulation resampling process. For the purpose of demonstration, we empirically apply the proposed method to the korean bank industry and compare its result with the result by the traditional deterministic DEA method. The nonparametric statistical hypothesis testing procedure in this study, which considers not only stochastic variability of the DEA data, but also random radial deviations off the efficient frontier, serves as a useful tool for dbjectively evaluating whether the mean difference of DEA efficiency estimates between groups is statistically significant.

  • PDF