• Title/Summary/Keyword: N distribution

Search Result 4,411, Processing Time 0.033 seconds

Evaluation of Fatigue Strain Intensity Factor on Fatigue Crack Propagation Rate (da/dN) (금속 재료의 피로 균열 전파 속도(da/dN) 평가를 위한 변형율 확대 계수의 유효성 검토)

  • 유재환;최재강;손종동
    • Journal of the Korean Society of Safety
    • /
    • v.11 no.2
    • /
    • pp.3-8
    • /
    • 1996
  • Fatigue fracture is the cyclic fracture phenomena at a very small local area near a crack tip. Therefore, the detailed quantitative experimental analysis about local cyclic strain distribution near a crack tip is prerequisite In order to make an effective parameter able to account for fatigue fracture problems. However, there are few reports on detailed quantitative experimental analysis of a local cyclic strain distribution near a crack tip, because of experimental difficulties. In this study, the distribution of local fatigue strains near a fatigue crack tip was in detail studied using by fine dot grid strain measurement method. From these results, a single parameter, which characterizes local fatigue strain field, was proposed. In addition, this parameter was applied to evaluate the fatigue crack propagation rate.

  • PDF

Design of Median Control Chart for Unsymmetrical Weibull Distribution (비대칭(非對稱)와이블분포공정(分布工程)에서 메디안특수관리도(特殊管理圖)의 설계(設計))

  • Sin, Yong-Baek;Hwang, Ui-Mi
    • Journal of Korean Society for Quality Management
    • /
    • v.14 no.2
    • /
    • pp.2-8
    • /
    • 1986
  • This thesis is concerned with the design of control chart based on the sample median which is easy to use in practical situations and to analyze the properties for non-normally distributed Weibull process. In this cases are use to the quality characteristics of the process are not normally distributed but skewed due to the intermitted production, small lot size and sample size is small one n=3 or n=5, etc. And when it relates unsymmetrically distributed process, model designed median control chart is more effective than Shewhart $\bar{x}$-chart which assumed on normal distribution, when we exactly should be known Weibull distribution or estimated. The median control chart in this thesis is more robustness compared with other conventionally developed control chart.

  • PDF

The Effects of Kinesio Taping application on the Pain, Weight-Bearing Distribution, and Walking Ability of Knee Osteoarthritis A Randomized Controlled Trial

  • Kim, Yang Rae;Park, Yong Nam
    • Journal of International Academy of Physical Therapy Research
    • /
    • v.9 no.3
    • /
    • pp.1537-1542
    • /
    • 2018
  • This study aimed to identify the effects of kinesio taping (KT) applied in a proprioceptive neuromuscular facilitation (PNF) pattern on the pain, weight-bearing distribution (WBD), and walking ability of knee osteoarthritis (KOA) patients. Thirty women with KOA were randomly allocated to a control group (n=15) with KT at the quadriceps only, and a PNF pattern group (n=15) with KT at the quadriceps and gastrocnemius muscle. Pain intensity was measured using a visual analogue scale during walking. In addition, WBD, and walking ability were measured before and 30 minutes after KT application. The VAS significantly reduced in both groups after the intervention (p<.05). WBD (p<.05, ES=.32) and walking ability (p<.05, ES=.38) showed a significant change in the PNF pattern group, and in the inter-group comparison, the PNF pattern group showed a significant difference compared to the control groups. These results demonstrate that KT application with PNF pattern effectively attenuate the pain and improves WBD and walking ability in KOA patients.

The Effects of Manual Therapy on Lower Extremity Alignment in Pelvic Malalignment

  • Jeon, Chang Keun;Han, Se Young;Yoo, Kyoung Tae
    • Journal of International Academy of Physical Therapy Research
    • /
    • v.9 no.3
    • /
    • pp.1543-1548
    • /
    • 2018
  • The purpose of this study was to analyze the effects of manual therapy on lower extremity alignment in pelvic malalignment. The subjects were 20 adults with pelvic malalignment. They were divided into two groups: manual therapy group (n=10) and stretching exercise group (n=10). Each group performed the intervention two times per week for 4 weeks. The lower extremity alignment was measured by pelvic deviation, functional leg length inequality, and plantar pressure distribution, which were measured between pre- and post-test. In the result of pelvic deviation, there was a significant difference between the pre- and post-test of the manual therapy group and stretching exercise group. In the result of the functional leg length inequality, there was a significant difference between the pre- and post-test of the manual therapy group. In the result of plantar pressure distribution, there was a significant difference between the pre- and post-test of the manual therapy group. These findings suggest manual therapy improves the pelvic deviation, functional leg length inequality, and plantar pressure distribution in the pelvic malalignment.

A Study on Inventory Control according to the Authorized Days for Supply Level (보급수준 인가일수에 따른 재고수준 산출에 관한 연구)

  • Jeong, Hai-Sung
    • Journal of Applied Reliability
    • /
    • v.7 no.3
    • /
    • pp.119-126
    • /
    • 2007
  • This paper deals with (s, S) spare part inventory model. Maintaining appropriate spare parts is one of the most important military affairs related to the readiness of military forces. In the problem under consideration, a military unit possesses n equipments and all the n equipments should be in operational readiness for the military purpose. The lifetime distribution of a part has been assumed to be exponential. This paper suggests the reorder point and order quantity under the assumption that the lifetime distribution of a part is weibull.

  • PDF

Analysis of the Gravity Effect on the Distribution of Refrigerant Flow in a Multi-circuit Condenser (다분지 응축기의 냉매유량 분배에 미치는 중력의 영향을 고려한 해석방법)

  • Lee Jangho;Kim Moo Hwan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.16 no.12
    • /
    • pp.1167-1174
    • /
    • 2004
  • The method to consider gravity effect on the performance of a condenser is developed, and a simple condenser having 'nU' type two circuits is analyzed. Each circuit has the same length and inlet air-side operational conditions. The only difference between two circuits is the direction of refrigerant flow, which is exactly opposite each other between the upper 'n' type circuit and the lower 'U' type circuit. It is shown that the gravity makes the distribution of refrigerant flow uneven in the two circuits at lower refrigerant flow rates; heat transfer rate also becomes uneven. Moreover, much of the refrigerant exists as liquid state in the circuit having low refrigerant flow rate, which will make the cycle balance unstable in the refrigeration cycle system like a heat pump.

Epidemiological Studies of Blast Disease of Rice Plant II. Significance of Differential Distribution of Leaf Lesions at Different Location of Each Tiller as an Inoculum Source of Panicle Blast (수도 도열병의 역학적 연구 II. 이삭 도열병 전염원으로서의 엽위별 병반분포의 의의)

  • Park J.S.;Yu S.H.;Kim H.G.
    • Korean journal of applied entomology
    • /
    • v.22 no.4 s.57
    • /
    • pp.277-282
    • /
    • 1983
  • Number and percentage of diseased area of leaf blast lesions formed on different leaf location were mostly distributed from the flag leaf(n-1) to the 3rd leaf from the top(n-3) in Tongil line rice varieties and on the 2nd leaf from the top(n-2) in Japonica type rice varieties. Especially leaf lesions of Nopung which was more susceptible to leaf blast among Ton1 line rice varieties were mostly distributed on flag leaf. Relation between the degree of lesion distribution and level of fertilizer was more clear with an increase of fertilizer quantity. Leaf blast lesions of rice varieties were generally distributed from the flag leaf to the with leaf from the top but mainly those at flag leaf and the 2nd leaf from the top were found to be most responsible for inoculum source of panicle blast after booting stage. Increase of the conidia formation was resulted from fluctuation of temperature$(24^{\circ}C\~16^{\circ}C)$ in low temperature range after booting stage and many inoculum sources were supplied on panicles until the end of September without impeding dispersal from leaf blast lesions as an inoculum source of panicle blast.

  • PDF

ON THE AGE DISIRIBUTION OF OPEN CLUSTERS

  • Hong, Seung-Soo;Kim, Yong-Ha;Lee, See-Woo
    • Journal of The Korean Astronomical Society
    • /
    • v.17 no.1
    • /
    • pp.1-14
    • /
    • 1984
  • Analyses of an integrated form $N(\tau)={\int}_{\tau}^{\infty}n(\tau)d{\tau}$ of the distribution of cluster ages, rather than its differential form $n(\tau)$, demonstrate that the observed distribution has clusters older than about 500 million years in a significant excess over theoretical model distributions. Considerations on cluster disruption processes show that a single disruption time-scale, frequently employed by current theoretical models, is no longer an adequate parameter for describing survival probability of clusters over wide age range, because different initial conditions of these clusters produce corresponding spreads in their lifetimes. To take into account for the spread in initial conditions, we have introduced an age-dependent disruption time, and deduced its age-dependence from the present-day age distribution of clusters. Results show a distinct two-stage variation: The newly introduced disruption time stays constant at about 50 million years for clusters younger than about 100 million years, while for clusters older than that it increases monotonically with the cluster age. This leads us to conclude that clusters experience different types of disrupting causes as they get old.

  • PDF

Distribution Levels of Phthalates and Di-2-ethylhexyladipate in Domestic Environment (국내 환경 중 프탈레이트 및 디에틸헥실아디페이트 잔류분포 특성)

  • Shin, Hye-Seoung;Shin, Jeoung Hwa;Ahn, Yun Gyong
    • The Korean Journal of Community Living Science
    • /
    • v.23 no.4
    • /
    • pp.411-418
    • /
    • 2012
  • Phthalates and di-2-ethylhexyladipate are both widely used as industrial chemicals and exposure high levels over long periods of time can cause toxicity, estrogenic responses and endocrine disruption properties in both humans and animals. So far, their global monitoring in environmental matrices has been performed continuously. A developed method, including modified SPEED'98 (Japan Environment Agency) and USEPA was established for simple and rapid determination of phthalates and di-2-ethylhexyladipate in various matrices. This method was applied to explore the distribution levels in domestic environmental media such as water, soil and sediment. Eight phthalates (DEP(di-ethyl), DEHP(di-[2-ethyl-hexyl]), DprP (di-propyl), DBP(di-n-butyl), DPP(di-n-pentyl), DHP(di-n-hexyl), DCHP(di-cyclohexyl), BBP(butyl benzyl) and Adipate (di-2-ethylhexyl adipate) were investigated by seasonal sampling(spring, autumn) at 24 domestic sites. Phthalates and adipate were not detected in water samples and DEP, DBP, and DEHP were mainly detected in soil and sediment samples. The concentrations of DEP and DBP excluding DEHP in spring were higher in soil than those of sediment. Total concentrations of phthalates were significantly decreased in autumn for both soil and sediment.

Metal Deposit Distribution in Barrel Plating of Partially Conductive Load

  • 이완구
    • Journal of the Korean Professional Engineers Association
    • /
    • v.16 no.3
    • /
    • pp.68-73
    • /
    • 1983
  • The metal deposition behavior in the barrel tin plating has been studied for the electronic DIP products, and tried to find out some modified factors in order to explain partial ,current flow behavior of this load. The deposition distribution characteristics for DTP products should be classified with the normal barrel plating as partially conductive load. Deposit distribution curves obtained from one-dimensional model have shown strong dependence n the applied current density, rotating speed of barrel and metal ion concentration of the solution. Theoretical formula J=$\delta$'/${\beta}$-{-c$^3$/${\gamma}$-exp-(1-${\alpha}$)n${\Phi}$} derived from one-dimensional porous model has been proposed for the barrel plating behavior where higher overpotential and concentration changes take place during barrel plating.

  • PDF