• 제목/요약/키워드: mean difference

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지니(Gini)의 평균차이를 이용한 산포관리도 (A Control Chart of the Deviation Based on the Gini′s Mean Difference)

  • 남호수;강중철
    • 산업경영시스템학회지
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    • 제24권67호
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    • pp.11-18
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    • 2001
  • The efficiency and robustness of the scale estimator based on the Gini's mean difference are well known in Nam et al.(2000). In this paper we propose use of robust control limits based on the Gini's mean difference for the control of the process deviation. To compare the performances of the proposed control chart with the existing R-chart or S-chart, some Monte Carlo simulations are performed. The simulation results show that the use of the Gini's mean difference in construction of the control limits has good performance.

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Tests for Normal Mean Change with the Mean Difference

  • Kim, Jaehee;Yun, Pilkyoung
    • Communications for Statistical Applications and Methods
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    • 제10권2호
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    • pp.353-359
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    • 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.

Low Contrast and Low kV CTA Before Transcatheter Aortic Valve Replacement: A Systematic Review

  • Spencer C. Lacy;Mina M. Benjamin;Mohammed Osman;Mushabbar A. Syed;Menhel Kinno
    • Journal of Cardiovascular Imaging
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    • 제31권2호
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    • pp.108-115
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    • 2023
  • BACKGROUND: Minimizing contrast dose and radiation exposure while maintaining image quality during computed tomography angiography (CTA) for transcatheter aortic valve replacement (TAVR) is desirable, but not well established. This systematic review compares image quality for low contrast and low kV CTA versus conventional CTA in patients with aortic stenosis undergoing TAVR planning. METHODS: We performed a systematic literature review to identify clinical studies comparing imaging strategies for patients with aortic stenosis undergoing TAVR planning. The primary outcomes of image quality as assessed by the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were reported as random effects mean difference with 95% confidence interval (CI). RESULTS: We included 6 studies reporting on 353 patients. There was no difference in cardiac SNR (mean difference, -1.42; 95% CI, -5.71 to 2.88; p = 0.52), cardiac CNR (mean difference, -3.83; 95% CI, -9.98 to 2.32; p = 0.22), aortic SNR (mean difference, -0.23; 95% CI, -7.83 to 7.37; p = 0.95), aortic CNR (mean difference, -3.95; 95% CI, -12.03 to 4.13; p = 0.34), and ileofemoral SNR (mean difference, -6.09; 95% CI, -13.80 to 1.62; p = 0.12) between the low dose and conventional protocols. There was a difference in ileofemoral CNR between the low dose and conventional protocols with a mean difference of -9.26 (95% CI, -15.06 to -3.46; p = 0.002). Overall, subjective image quality was similar between the 2 protocols. CONCLUSIONS: This systematic review suggests that low contrast and low kV CTA for TAVR planning provides similar image quality to conventional CTA.

지니(Gini)의 평균차이에 기초한 $\overline{X}$-관리도 (An $\overline{X}$-Control Chart Based on the Gini′s Mean Difference)

  • 남호수;강중철
    • 품질경영학회지
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    • 제29권3호
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    • pp.79-85
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    • 2001
  • Estimation of the process deviation is an important problem in statistical process control, especially in the control chart, process capability analysis or measurement system analysis. In this paper we suggest the use of the Gini's mean difference for the estimation of the process deviation when we design the control limits in construction of the control charts. The efficiency of the Gini's mean difference was well explained in Nam, Lee and Jung(2000). In this paper we propose an $\overline{X}$ control chart which use the control limits based on the Gini's mean difference. In various classes of distributions, the proposed control chart shows food performance.

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

  • 홍순이;정문숙
    • 보건교육건강증진학회지
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    • 제11권1호
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    • pp.3-15
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    • 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.

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수종 근관형성방법에 따른 레진모형상의 근관형태의 변화 (EFFECTS OF DIFFERENT PREPARATION METHODS ON THE MORPHOLOGIC CHANGE OF SIMULATED ROOT CANALS IN RESIN BLOCK)

  • 박미희;홍찬의
    • Restorative Dentistry and Endodontics
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    • 제19권1호
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    • pp.85-96
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    • 1994
  • In this study, 24 curved resin blocks were prepared by one of the following four methods: 1) Conventional technique using K-flexo files 2) Step-back technique using K-flexo files 3) Crown-down technique using K-flexo files 4) Canal Master instrumentation using Canal Master Resin blocks were sectioned, photographed, and evaluated the mean centering ratio and the mean area of dentin removed before and after the instrumentation. The results were as follows : I. the mean centering ratio 1. In the level 1 and level 3, there was no significant difference in the mean centering ratio. 2. In the level 2, Step-back technique showed the worst mean centering ratio among the tested groups(p<0.001) and there was no significant difference between the other three groups. 3. In the level 4, Canal Master instrumentation and Step-back technique showed better mean centering ratio than the other two techniques(p<0.001) and there was no significant difference between the two techniques. II. the mean area of dentin removed 1. In the level l and level 3, there was no significant difference in the mean area of dentin removed. 2. In the level 2, Canal Master instrumentation removed less dentin than the other three techniques(P<0.01). 3. In the level 4, Crown-down technique removed less dentin than the other three techniques(P<0.05).

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여성에 있어서의 비만도에 따른 우울, 불안, 자아존중감의 차이 -기초연구- (Differences in Depression, Anxiety, Self-esteem According to the Degree of Obesity in Women -A Pilot Study-)

  • 이준환;김광호;김종우
    • 동의신경정신과학회지
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    • 제13권2호
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    • pp.93-100
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    • 2002
  • Objects and Methods : BDl, STAI and Self-Esteem scale were completed by 28 female subjects who composed of nurses of Kyung Hee Medical Center and students of Kyung Hee Oriental Medical college. At the same time, current weight, height and BMI(Body Mass Index), ideal weight, height and BMI, the difference of current weight and ideal weight, the difference of current height and ideal height, and the difference of current BMI and ideal BMI were measured. Result : 1. There was a significant difference between obese and normal weight group in the difference between the current weight and the ideal weight. The difference of the obese group were higher than the normal weight group. 2. There was a significant difference between obese and normal weight group in the mean BDI score. The mean BDI score of the obese group were higher than that of the normal weight group. 3. There was no significant difference between obese and normal weight group in the mean STAI score. 4. There was no significant difference between obese and normal weight group in the mean Self-Esteem Scale score. Conclusion : There are a tendency; the more weight, the more depression in women.

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지니(Gini)의 평균차이를 이용한 공정산포 추정 (On the Estimation of the Process Deviation Based on the Gini's Mean Difference)

  • 남호수;이병근;정현석
    • 산업경영시스템학회지
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    • 제23권58호
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    • pp.113-118
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    • 2000
  • Estimation of the process deviation is an important problem in statistical process control, especially in the control chart, process capability analysis or measurement system analysis. In this paper we suggest the use of the Gini's mean difference for the estimation of the c, the measure of the process deviation through a lots of simulations in various types of distributions. The Gini's mean difference uses the differences of all possible pairs of data. This point will improve the efficiency of estimation. In various classes of distributions, the Gini's mean difference shows good performance, in sense of bias of estimates or mean squared errors.

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한국성우(韓國成牛)의 혈액학치(血液學値) 및 혈액화학치(血液化學値)에 관한 연구(硏究) 제2보(第二報) 한국성우(韓國成牛)의 혈액화학치(血液化學値)에 관한 연구(硏究) (Studies on the Hematology and Blood Chemistry of Korean Cattle Part II. Studies on the Blood Chemistry of Korean Cattle)

  • 정창국
    • 대한수의학회지
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    • 제5권1호
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    • pp.97-123
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    • 1965
  • Observations were made on the blood picture of total 196 heads of healthy Korean cattles, including 98 males and females in the purpose of determination of blood chemical values and their sex differences and seasonal variations during one year period from December, 1963 to November, 1964. The blood sampling were scheduled by random in four different seasons and the sample size of both sex included in each season were designated to be same size. The ranges, averages or mean values of the blood glucose, total serum protein, serum globulin, serum albumin, total non-protein nitrogen, blood urea nitrogn, total serum cholesterol, serum inorganic phosphorus and serum calcium were determined in this studies and their respective standard deviation, standard error of means, sex differences and seasonal variations were as follows. 1. The blood glucose values for the male ranged from 32.8 to 70.0 mg/100cc. with a mean of $49.781{\pm}0.823mg/100cc$; for the female the range was 32.0 to 64.0mg/100cc. with a mean of $47.235{\pm}0.782mg/100cc$. Sex difference showed significant at 5% level and seasonal variation was highly significant at 1% level. 2. The total serum protein values for the male ranged from 5.61 to 8.83 gm/100cc with a. mean of $7.366{\pm}0.062gm/100cc$; for the female ranged from 5.53 to 8. 43 gm/100cc. with a mean of $6.832{\pm}0.063gm/100cc$. Sex difference and seasonal variation was not significant. 3. The serum globulin values for the male ranged from 2.97 to 4.78 gm/100cc. with a mean of $3.961{\pm}0.039gm/100cc$.; for the female ranged from 2.87 to 4.41 gm/100cc. with a mean of $3.699{\pm}0.037gm/100cc$. Sex difference showed highly significant at 1% level and seasonal variation was not significant. 4. The serum albumin values for the male ranged from 2.58 to 4.21 gm/100cc. with a mean of $3.405{\pm}0.029gm/100cc$.; for the female ranged from 2.39 to 4.10 gm/100cc. with a mean of $3.204{\pm}0.031gm/100cc$. Sex difference showed highly significant at 1% level and seasonal variation was not significant. 5. The total non-protein nitrogan values for the male ranged from 19.1 to 44.8 gm/100cc. with a mean of $31.166{\pm}0.582mg/100cc$.; for the female the range was 15.2 to 50.5 mg/100cc. with a mean of $28.89.6{\pm}0.673mg/100cc$. Sex difference showed significant at 5% level and seasonal variation was highly significant at 1 % level. 6. The blood urea nitrogen values for the male ranged from 6.4 to 28.3 mg/100cc. with a mean of $13.371{\pm}0.466mg/100cc$.; for the female the range, was 6.0 to 26.9 mg/100cc. with a mean of $13.631{\pm}0.321mg/100cc$. Sex difference was not significant and seasonal variation showed highly significant at 1 % level. 7. The total serum cholesterol values for the male ranged from 60.0 to 238.6 mg/100cc. with a mean of $140.897{\pm}2.826mg/100cc$.; for the female ranged from 50.0 to 243.0 mg/100cc. with a mean of $124.840{\pm}3.553mg/100cc$. Sex difference and seasonal variation showed highly significant at 1% level. 8. The serum inorganic phosphorus values for the male ranged from 3.5 to 7.8 mg/100cc. with a mean of $5.426{\pm}0.096mg/100cc$.; for the female ranged from 3.1 to 8.8 mg/100cc. with a mean of $5.570{\pm}0.128mg/100cc$. Sex difference and seasonal variation showed no significant. 9. The serum calcium values for the male ranged from 7.8 to 12.8 mg/100cc. with a mean of $10.761{\pm}0.102mg/100cc$.; for the female ranged from 8.0 to 13.0 mg/100cc. with a mean of 10. $756{\pm}0.097mg/100cc$. Sex difference was not significant and seasonal variation showed highly significant at 1% level. 10. The age of test group ranged from 2 years to 6 years in both sex and the averageage were, $4.45{\pm}0.114$ years in male and $4.50{\pm}0116$ years in female. Sex difference and seasonal variation of age were not found to be significant.

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블럭 정합 알고리즘을 위한 적응적 비트 축소 MAD 정합 기준과 VLSI 구현 (An Adaptive Bit-reduced Mean Absolute Difference Criterion for Block-Matching Algorithm and Its VlSI Implementation)

  • 오황석;백윤주;이흥규
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제27권5호
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    • pp.543-550
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    • 2000
  • 블럭 정합 알고리즘의 VLSI 구현시 복잡도를 줄이고, 수행 속도를 높이기 위하여 새로운 정합 기준인 적응적 비트 축소 MAD(adaptive bit-reduced mean absolute difference:ABRMAD)를 제안한다. ABRMAD는 기존의 MAD에서 화소의 모든 비트를 비교하는 대신, 화소를 구성하는 중요한 비트만을 고려하여 축소된 화소 값을 비교하여 움직임 벡터를 찾는다. 실험을 통하여, 제안한 정합 기준은 기존의 MAD 정합 기준에 비하여 낮은 하드웨어 복잡도를 가지면서 MSE(mean square error) 측면에서 유사한 성능을 가짐을 보인다. 또한 기존의 비트 수 축소형 정합 기준인 DPC(difference pixel counting), BBME(binary-matching with edge-map), 그리고 BPM(bit-plane matching)과 비교하여 같은 수의 비트를 사용하였을 경우 좋은 MSE 성능을 가짐을 보인다.

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