• 제목/요약/키워드: confidence limit

검색결과 218건 처리시간 0.031초

ReliabIlity analysis of containment building subjected to earthquake load using response surface method

  • Lee, Seong Lo
    • Computers and Concrete
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    • 제3권1호
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    • pp.1-15
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    • 2006
  • The seismic safety of reinforced concrete containment building can be evaluated by probabilistic analysis considering randomness of earthquake, which is more rational than deterministic analysis. In the safety assessment of earthquake-resistant structures by the deterministic theory, it is not easy to consider the effects of random variables but the reliability theory and random vibration theory are useful to assess the seismic safety with considering random effects. The reliability assessment of reinforced concrete containment building subjected to earthquake load includes the structural analysis considering random variables such as load, resistance and analysis method, the definition of limit states and the reliability analysis. The reliability analysis procedure requires much time and labor and also needs to get the high confidence in results. In this study, random vibration analysis of containment building is performed with random variables as earthquake load, concrete compressive strength, modal damping ratio. The seismic responses of critical elements of structure are approximated at the most probable failure point by the response surface method. The response surface method helps to figure out the quantitative characteristics of structural response variability. And the limit state is defined as the failure surface of concrete under multi-axial stress, finally the limit state probability of failure can be obtained simply by first-order second moment method. The reliability analysis for the multiaxial strength limit state and the uniaxial strength limit state is performed and the results are compared with each other. This study concludes that the multiaxial failure criterion is a likely limit state to predict concrete failure strength under combined state of stresses and the reliability analysis results are compatible with the fact that the maximum compressive strength of concrete under biaxial compression state increases.

불안정한 지지면에서의 과제지향 순환훈련이 아급성기 뇌졸중 환자의 균형, 보행 및 균형자신감에 미치는 영향 (The Effects of Task-Oriented Circuit Training Using Unstable Surface on Balance, Walking and Balance Confidence in Subacute Stroke Patients)

  • 김선민;강순희
    • 대한통합의학회지
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    • 제9권4호
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    • pp.211-223
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    • 2021
  • Purpose : The purpose of this study was to examine the effect of task-oriented circuit training using unstable support surface on balance, gait ability, and balance confidence in subacute stroke patients. Methods : Forty-five patients with subacute stroke were randomly divided into the three following groups of 15: 1) TOCT-US group; task-oriented circuit training using unstable surface (experimental group 1), 2) TOCT-SS group; task-oriented circuit training using stable surface (experimental group 2), and 3) CON group; conventional physical therapy (control group). All patients participated in one of the three training programs for 6 weeks, 30 minutes per session, 3 times per week. Patients' balance ability was assessed using the BT-4, BBS (berg balance scale), TUG (time up and go test), and LOS (limit of stability). Gait speed was measured to examine gait ability. K-ABC (activities-specific balance confidence scale) was also used to assess the level of patients' confidence in daily activities. Results : After the intervention, the sway area in experimental groups 1 and 2 decreased, but that in the control group increased. Experimental group 1 showed significant improvement compared with experimental group 2 and the control group. BBS, TUG, and LOS scores of experimental group 1 were significantly improved compared with those of experimental group 2 and the control group. Also, gait speed significantly improved in experimental group 1 compared with experimental group 2 and the control group. Experimental groups 1 and 2 showed significant improvement in K-ABC scores after training. Conclusion : Patients with subacute stroke had significantly improved balance, gait, and level of confidence in performing activities of daily living following task-oriented circuit training using the unstable surface. This indicates that task-oriented circuit training using unstable surfaces can be an effective treatment method for the recovery of balance and gait in subacute stroke patients.

와이블-역승법을 이용한 기계류부품의 가속시험 방법 개발 (Development of accelerated life test method for mechanical components using Weibull-IPL(Inverse Power Law) model)

  • 이근호;김형의;강보식
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.445-450
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    • 2003
  • This study was performed 10 develop the accelerated life test method using Weibull-IPL(Inverse Power Law) model for mechanical components. Weibull-IPL model is concerned with determining the assurance life with confidence level and the accelerated life test time From the relation of weibull distribution factors and confidence limit, the testing times on the no number of failure acceptance criteria arc determined. The mechanical components generally represent wear and fatigue characteristics as a failure mode. IPL based on the cumulative damage theory is applied effectively the mechanical components to reduce the testing time and to achieve the accelerating test conditions. As the actual application example, accelerated life test method of agricultural tractor transmission was described. Life distribution of agricultural tractor transmission was supposed to follow Weibull distribution and life test time was calculated under the conditions of average life (MTBF) 3,000 hours and 90% confidence level for one test sample. According to IPL, because test time call be shorten in case increase test load test time could be reduced by 482 hours when we put the load 1.1 times of rated load than 0.73 times of rated load that is equivalent load calculated by load spectrum of the agricultural tractor. This time, acceleration coefficient was 11.7.

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Application of Bootstrap Method to Primary Model of Microbial Food Quality Change

  • Lee, Dong-Sun;Park, Jin-Pyo
    • Food Science and Biotechnology
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    • 제17권6호
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    • pp.1352-1356
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    • 2008
  • Bootstrap method, a computer-intensive statistical technique to estimate the distribution of a statistic was applied to deal with uncertainty and variability of the experimental data in stochastic prediction modeling of microbial growth on a chill-stored food. Three different bootstrapping methods for the curve-fitting to the microbial count data were compared in determining the parameters of Baranyi and Roberts growth model: nonlinear regression to static version function with resampling residuals onto all the experimental microbial count data; static version regression onto mean counts at sampling times; dynamic version fitting of differential equations onto the bootstrapped mean counts. All the methods outputted almost same mean values of the parameters with difference in their distribution. Parameter search according to the dynamic form of differential equations resulted in the largest distribution of the model parameters but produced the confidence interval of the predicted microbial count close to those of nonlinear regression of static equation.

소형견의 전립선 크기에 관한 초음파적 연구 (Ultrasonographic Estimation of Prostatic Size of Toy Breed Dogs)

  • 윤화중;최치봉;배춘식
    • 한국임상수의학회지
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    • 제17권1호
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    • pp.168-172
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    • 2000
  • Prostatic length and height on sagittal images and prostatic width and height on transverse images were measured ultrasonographically to establish upper limit of the prostate in 45 dogs which were clinically healthy and sexuallly intact. Linear 5regression and correlatin analysis were performed between prostatic parameters(length and height on sagittal images & width and height on transverse images) and parameters related to body size(body weight, left kidney length) and age of the dogs. Prostatic parameters were significantly correlated with body size and age of the dogs. Maximum predicted values with body weight and age for prostatic parameters were determined based o the upper limit of the 95% confidence interval of the mean predicted values. Such values should be useful for the small animal clinicians in determining if the prostate gland is too large for a given body weight and age, and may contribute to clinicl signs.

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RFID기반의 Reference Tag를 이용한 쇼핑 고객 위치추적 및 동선분석에 관한 연구 (A Study for Shopping Customer's Location Tracking and Moving Line Analysis Using Reference Tag on based RFID)

  • 임상민;이근왕
    • 한국산학기술학회논문지
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    • 제10권1호
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    • pp.151-157
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    • 2009
  • 본 연구에서는 오프라인 쇼핑몰에서 실시간 위치추적 기술과 USB 메모리와 RF가 융합된 Tag(이하 u-Card라 함)를 이용하여 위치추적 및 동선분석의 한계점을 개선하고 레퍼런스 태그를 이용한 위치추적을 통해 정확하고 신뢰성을 향상시키며 차폐물 간섭에 의한 오차율에 대한 한계점을 개선한 알고리즘 및 위치추적엔진 모듈을 제안한다.

시가지 발파에서 공저 전색물이 발파진동에 미치는 영향 (The Effect of Bottom-Hole Stemming Materials on Vibration Level at Urban Area Blasting)

  • 강추원
    • 터널과지하공간
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    • 제7권1호
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    • pp.51-57
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    • 1997
  • This study provides the results of two different blasting methods applied at the H Telcon construction site in Yeon-dong, Cheju Island. One is the traditional blasting method without bottom-hole stemming and the other with bottom-hole stemming using the materials such as sand, polystyrene and sawdust in 5~10 cm lengths. The effect of these materials on vibration level was studied. Assuming that safety criterion of vibration level be 0.5cm/set, 95% confidence limit line of measured data shows that maximum charge weight per delay could be increased in the following order; traditional methed, polystyrene stemming, sand stemming, sawdust stemming.

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ASYMPTOTIC PROPERTIES OF RANDOM CENTRAL ORDER STATISTICS UNDER CONTAMINATION

  • Kim, Sung-Kyun;Kim, Sung-Lai
    • Journal of applied mathematics & informatics
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    • 제8권2호
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    • pp.627-634
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    • 2001
  • Under contamination, Bahadur representations with a strong remainder term are derived for random central order statistics with a prescribed limiting rank, and asymptotic normalities for these statistics of truncated and contaminated data are proved, with a suitable limiting rank. From these results, an application to the fixed-width confidence interval problem is available.

공정능력(工程能力) 향상(向上)을 위한 실험계량적(實驗計劃的) 연구(硏究) (Improving Process Capability by Applying Design and Analysis of Experiment)

  • 송서일
    • 품질경영학회지
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    • 제16권1호
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    • pp.15-22
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    • 1988
  • This paper analysis the process capability by applying experiment design to control alcohol in soluble matter mixing process of laundry soap. The results are summarized as follows: (1) Alcohol insoluble matter shows the tendency of increasing according to the mixing temperature (A) and beating velocity (B). (2) The most suitable working condition of the mixing process is $A_2B_2$, and 95% confidence limit of alcohol insoluble matter is $22.06{\pm}0.77%$. (3) The process capability index ($C_p$) of the mixing process is improved from 0.64 to 1.68.

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광어에서 Cephalexin의 잔류 소실에 관한 연구 (Residue Depletion of Cephalexin in the Flounder (Paralichthys olivaceus))

  • 임종환;장범수;박병권;윤효인
    • 대한수의학회지
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    • 제43권3호
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    • pp.435-438
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    • 2003
  • The objective of this study was to investigate the residue depletion of cephaalexin in the flounder (Paralichthys olivaceus) after multiple oral administrations and to establish the appropriate withdrawal time for edible tissues. A highly sensitive and specific method for the determination of cephalexin in the serum of flounder by LC/MS was developed and validated. Mean recoveries from serum were 87.2% (ranged from 81.2% to 94.5%) for cepalexin. Recovery and precision met the criteria for the guideline of residual analysis of veterinary drugs by the National Veterinary Research and Quarantine Service (NVRQS) in Korea. The limit of detection and limit of quantitation of cephalexin were 10 ng/ml and 50 ng/ml, respectively. Residual levels of cephalexin in muscle samples were estimated with 95% tolerance limit and 95% confidence to fall below the MRL after a withdrawal time of 4 days and 5 days for the 40 and 160 mg/kg/day, respectively.