• 제목/요약/키워드: Statistical treatment

검색결과 2,574건 처리시간 0.031초

SCM415 침탄질화 처리재의 통계학적 피로거동에 대한 연구 (The Statistical study on the fatigue bebavior of Nitro -Carburized SCM415 steel)

  • 송삼홍;이상훈;임세혁
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 춘계학술대회 논문집
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    • pp.719-723
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    • 1996
  • In this research, The statistical characteristics of non-heated and nitro-carburized specimens are investigated under two stress levels (1.15 .sigma. $_{w}$ .leq. .sigma.$_{\alpha}$ .leq. 1.25 .sigma. $_{w}$). Seven specimens of each stress level are tested by rotary bending fatigue machine. The cycles about each crack length and crack propagation rate are used as statistical variagle of weibull distribution. By using concept of reliability function, reliable S-N formula of Nitro-Carburized specimen are gotten.ten.

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통계적 방법을 이용한 복합조직강의 변형률과 보이드 성장거동에 관한 연구 (A Study on Strain-Void Growth Mechanism of Dual Phase Steel by Statistical Method)

  • 오경훈;유용석;오택열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.533-538
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    • 2000
  • Ductile fracture of dual phase steel begins with void nucleation, at martensite-ferrite interface of deformed martensite particle. In this study, void nucleation, growth, and coalescence under various strain were studied in dual phase steel. Therefore, by means of the heat treatment of low carbon steel, the study deals with void nucleation and growth for ferrite grain size and martensite volume fraction of dual phase steel using statistical method. Void nucleation and growth with increasing strain are shown depend upon the ferrite grain size. Voids volume fraction generally increase as ferrite grain size decease.

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Generalized half-logistic Poisson distributions

  • Muhammad, Mustapha
    • Communications for Statistical Applications and Methods
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    • 제24권4호
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    • pp.353-365
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    • 2017
  • In this article, we proposed a new three-parameter distribution called generalized half-logistic Poisson distribution with a failure rate function that can be increasing, decreasing or upside-down bathtub-shaped depending on its parameters. The new model extends the half-logistic Poisson distribution and has exponentiated half-logistic as its limiting distribution. A comprehensive mathematical and statistical treatment of the new distribution is provided. We provide an explicit expression for the $r^{th}$ moment, moment generating function, Shannon entropy and $R{\acute{e}}nyi$ entropy. The model parameter estimation was conducted via a maximum likelihood method; in addition, the existence and uniqueness of maximum likelihood estimations are analyzed under potential conditions. Finally, an application of the new distribution to a real dataset shows the flexibility and potentiality of the proposed distribution.

통계적 에너지 해석법을 이용한 소형 잔향실의 연성손실계수 측정 (Calculation of Coupling Loss Factor for Small reverberation cabin using Statistical Energy Analysis)

  • 김관주;김운경;윤태중;김정태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.797-801
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    • 2003
  • The Statistical Energy Analysis is based on the power flow and the energy conservation between sub-systems, which enable the prediction of acoustic and structural vibration behavior in mid-high frequency ranges. This paper discusses the identification of SEA coupling loss factor parameters from experimental measurements of small reverberation chamber sound pressure levels and structural accelerations. As structural subsystems, steel plates with and without damping treatment are considered. Calculated CLFs were verified by both transmission loss values for air-borne CLF case and running SEA commercial software As a result, CLFs have shown a good agreement with those computed by software. Acoustical behavior of air-borne noise and structure-borne noise has been examined. which shows reasonable results, too.

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침탄질화 처리된 SCM415재의 피로거동에 대한 통계적 연구 (A Statistical Study on the Fatigue Behaviors of Nitro-Carburized SCM415)

  • 송삼홍;이상훈;임세혁
    • 한국정밀공학회지
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    • 제14권5호
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    • pp.128-133
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    • 1997
  • Due to their high strength and good wear resistance, nitro-carburizing materials have been used for many machine components. However, the nitro-carburizing materials are found to have one disadvantage ; that is, their strength and fatigue life show larger scatter than those of non-heated metals. In this paper, therfore, the statistical chracteristics of non-heated and nitro-carburized specimens for SCM415 are investi- gated under two different of stress levels 1.15 .sigma. /sub .omega. / .leq. / .sigma. / sub .alpha. / .leq. / 1.25 .sigma. /sub .omega. /. Seven specimens at each stress level are tested by using rotating bending fatigue tester. The relation between a crack length and fatigue cycles can be arranged for Weibull distribution, and S-N curve using 95% reliability function is obtalined for nitro-carburized specimen.

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THE USE OF MULTIVARIATE STATISTICS TO EVALUATE THE RESPONSE OF RICE STRAW VARIETIES TO CHEMICAL TREATMENT

  • Vadiveloo, J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제9권1호
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    • pp.83-89
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    • 1996
  • Multivariate statistical procedures were used to analyse data on the chemical composition and in vitro digestibility of four varienties of rice straw after treatment with 4% NaOH solution, 4% urea solution or distilled water (control) for 48 hours. For each treatment, stepwise discriminant analysis identified the variables which maximized differences between varieties and the eigenvectors from principal component analysis quantified the contribution of these criterion variables to varietal differences. The overall response of varieties to chemical treatment was demonstrated qualitatively, by cluster analysis, and quantitatively, from the magnitude of the principal component scores. The analysis revealed that the urea and control treatments elicited the same response whereas NaOH had the greatest effect on the poorest straw variety. Similar analyses conducted on the botanical fractions of the varieties showed that the relative response of the inflorescence, stem, leaf blade and leaf sheath fractions was not altered by chemical treatment.

전방재위치 교합장치를 이용한 비정복성 관절원판변위 환자의 치험례 (Case Report : Treatment of Disc Displacement without Reduction Patient Using ARS)

  • 진상배;홍정표
    • Journal of Oral Medicine and Pain
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    • 제23권3호
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    • pp.277-280
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    • 1998
  • The treatment of anterior disc displacement without reduction patients needs speicific treatment methods different from other Craniomandibular Disorders. Those are manual manipulation, anterior repositioning splint; ARS and step-back. It is well known that the use of Anterior Repositioning Splint is effective on relief of TMJ symptom. But the side effect of long- term ARS wearing, which is irreversible posterior open bite induction, has made many clinicians avoid ARS treatment. This report introduces a clinical case recently proven part- time wearing ARS method for treatment of Disc Displacement without reduction patient' that can reduce side effects with good efficacy. But now clinical statistical studies and basical histophysiological studies are more needed.

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An Efficient and Easy Discretizing Method for the Treatment of Noise Factors in Robust Design

  • Lanzotti, Antonio;Vanacore, Amalia
    • International Journal of Quality Innovation
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    • 제8권3호
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    • pp.188-197
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    • 2007
  • In this work, an efficient and easy statistical method to find an equivalent discrete distribution for a continuous random variable (r.v.) is proposed. The proposed method is illustrated by applying it to the treatment of the anthropometrical noise factors in the context of Robust Ergonomic Design.

지수분표에 있어서 최우수 처리의 판별을 위한 우도비 검정 (The likelihood ratio test for detecting the best treatment among several exponential populations)

  • 황형태
    • 응용통계연구
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    • 제8권1호
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    • pp.151-157
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    • 1995
  • 다수의 지수분포에 있어서 최우수 처리를 판별하는 방법을 가설검정의 형식으로 연구하였다. 최우수 처리의 판별을 위해 적절한 가설을 설정하고, 주어진 유의수준을 만족시키는 우도비 검정 방법을 유도하였으며, 관심영역에서의 최소 검정력을 계산함으로써 실제 표본 설계가 가능하도록 하였다.

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기능성 소화불량증에 대한 침치료의 효과;무작위배정 대조군 연구 (Effect of Acupuncture Treatment for Functional Dyspepsia;A Randomized Controlled Trial)

  • 박양춘;조정효;손창규;홍권의;정인철;강위창;최선미
    • Journal of Acupuncture Research
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    • 제24권1호
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    • pp.1-12
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    • 2007
  • Objectives : Functional dyspepsia is a prevalent disease. It impedes subjective quality of life. The purpose of this research is to examine the effect of acupuncture treatment for functional dyspepsia. Methods : In this randomized, single blind, placebo-controlled study, we compared active acupuncture with sham acupuncture for the treatment of functional dyspepsia. Volunteers who satisfied the requirements were enrolled in study. Severity of dyspepsia was measured by Nepean Dyspepsia Index(NDI) and Functional Dyspepsia Quality fo Life(FD-QOL) before and after treatments. Results : 68 subjects finished study. There were not difference between two groups on age, sex, weight, height, severity of dyspepsia, subtype, Byeonjeung, surmise of treatment. After treatment total key symptoms score, improve rate of key symptoms were decreased than before treatment in active acupuncture group, but there were no statistical significance compared with sham acupuncture group. After treatment "pressure in upper abdomen" and " cramps in upper abdomen" were more decreased in active acupuncture group compared with sham acupuncture group(p=0.001, p=0.014). After treatment total symptom score and QOL of NDI were decreased than before treatment in active acupuncture group, but there were no statistical significance compared with sham acupuncture group. After treatment eating status of FD-QOL in active acupuncture group was significantly increased than sham acupuncture group(p=0.008). After treatment liveliness status of FD-QOL and total score of FDQOL in active acupuncture group was increased than sham acupuncture group though statistically insignificant(p=0.095, p=0.077). Conclusion : Acupuncture treatment is effective to improve the symptoms and quality of life in patients with functional dyspepsia.

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