• 제목/요약/키워드: Average number of samples

검색결과 353건 처리시간 0.032초

선택적 누적합(S-CUSUM) 관리도 (A Selectively Cumulative Sum(S-CUSUM) Control Chart)

  • 임태진
    • 품질경영학회지
    • /
    • 제33권3호
    • /
    • pp.126-134
    • /
    • 2005
  • This paper proposes a selectively cumulative sum(S-CUSUM) control chart for detecting shifts in the process mean. The basic idea of the S-CUSUM chart is to accumulate previous samples selectively in order to increase the sensitivity. The S-CUSUM chart employs a threshold limit to determine whether to accumulate previous samples or not. Consecutive samples with control statistics out of the threshold limit are to be accumulated to calculate a standardized control statistic. If the control statistic falls within the threshold limit, only the next sample is to be used. During the whole sampling process, the S-CUSUM chart produces an 'out-of-control' signal either when any control statistic falls outside the control limit or when L -consecutive control statistics fall outside the threshold limit. The number L is a decision variable and is called a 'control length'. A Markov chain approach is employed to describe the S-CUSUM sampling process. Formulae for the steady state probabilities and the Average Run Length(ARL) during an in-control state are derived in closed forms. Some properties useful for designing statistical parameters are also derived and a statistical design procedure for the S-CUSUM chart is proposed. Comparative studies show that the proposed S-CUSUM chart is uniformly superior to the CUSUM chart or the Exponentially Weighted Moving Average(EWMA) chart with respect to the ARL performance.

의암땜 하류수역의 분변성 오염세균류의 분포 (Occurrence Of Fecal Pollution Bacteria In The Water Of Lake Eui-Am)

  • 최상;김건치
    • 한국해양학회지
    • /
    • 제5권2호
    • /
    • pp.59-64
    • /
    • 1970
  • 지표를 스치며 많은 분,지류가 모여 이루어지는 각 하천수에는 적지않은 수량의 세균류가 혼입된다. 이것들은 결국 바다로 유입되어 연안 동,식물에 섭취되거나 또는 부착되어 또다시 우리의 식생활에 이입되는 순환을 거듭하고 있고, 이러한 과정에서 각종 질병의 원인이 유발되는 수가 적지 않다. 이러한 관점에서 환경수의 세균오염은 우리의 보건위생면에서, 가정용수 또는 산업용수의 이용면에서 매우 중요한 의의를 갖는 것이라고 하겠다.

  • PDF

Fiber orientation distribution of reinforced cemented Toyoura sand

  • Safdar, Muhammad;Newson, Tim;Waseem, Muhammad
    • Geomechanics and Engineering
    • /
    • 제30권1호
    • /
    • pp.67-73
    • /
    • 2022
  • In this study, the fiber orientation distribution (FOD) is investigated using both micro-CT (computerized tomography) and image analysis of physically cut specimens prepared from Polyvinyl Alcohol (PVA) fiber reinforced cemented Toyoura sand. The micro-CT images of the fiber reinforced cemented sand specimens were visualized in horizontal and vertical sections. Scans were obtained using a frame rate of two frames and an exposure time of 500 milliseconds. The number of images was set to optimize and typically resulted in approximately 3000 images. Then, the angles of the fibers for horizontal sections and in vertical section were calculated using the VGStudio MAX software. The number of fibers intersecting horizontal and vertical sections are counted using these images. A similar approach was used for physically cut specimens. The variation of results of fiber orientation between micro-CT scans and visual count were approximately 4-8%. The micro-CT scans were able to precisely investigate the fiber orientation distribution of fibers in these samples. The results show that 85-90% of the PVA fibers are oriented between ±30° of horizontal, and approximately 95% of fibers have an orientation that lies within ±45° of the horizontal plane. Finally, a comparison of experimental results with the generalized fiber orientation distribution function 𝜌(θ) is presented for isotropic and anisotropic distribution in fiber reinforced cemented Toyoura sand specimens. Experimentally, it can be seen that the average ratio of the number of fibers intersecting the finite area on a vertical plane to number of fibers intersecting the finite area on a horizontal plane (NVtot/NHtot) cut through a sample varies from 2.08 to 2.12 (an average ratio of 2.10 is obtained in this study). Based up on the analytical predictions, it can be seen that the average NVtot/NHtot ratio varies from 2.13 to 2.17 for varying n values (an average ratio of 2.15).

Quantitative analysis by the CARNAC procedure

  • Davies, Anthony M.C.;Fearn, Tom
    • 한국근적외분광분석학회:학술대회논문집
    • /
    • 한국근적외분광분석학회 2001년도 NIR-2001
    • /
    • pp.1124-1124
    • /
    • 2001
  • CARNAC is a procedure for obtaining quantitative analysis of a sample by comparison of the NIR spectra of the unknown sample with a database of a large number of samples with NIR spectral and compositional data. The method depends on the compression of the NIR database followed by a modification of the compressed data which emphasizes the required analyte. The method identifies a few very similar samples and the value of the required analyte is calculated from a weighed average of the analyte values for the selected similar samples. The method was originally described at Chambersburg IDRC in 1986 and in the Proceedings of the FT Conference of 1987. This contribution will describe recent work on utilising new methods for both compression and modification.

  • PDF

Probability Density Function of Samples' Amplitude of ASSS OFDM Signal

  • Wang, Lei;Yoon, Dong-Weon;Park, Sang-Kyu
    • Journal of electromagnetic engineering and science
    • /
    • 제8권2호
    • /
    • pp.59-63
    • /
    • 2008
  • The adaptive symbol selection scheme(ASSS) is popular in reducing peak to average power ratio(PAPR) for orthogonal frequency division multiplexing(OFDM) signals. The probability density function(pdf) of the samples' amplitudes of the adaptively selected OFDM signal without over-sampling has been considered to be approximately equal to the Rayleigh pdf. In this paper, we derive a more precise pdf which shows the relationship between the probability distribution of the samples' amplitudes and the number of the candidate symbols for ASSS. Using the newly derived pdf in the theoretical analysis, more accurate calculation results can be obtained.

Data Pattern Estimation with Movement of the Center of Gravity

  • Ahn Tae-Chon;Jang Kyung-Won;Shin Dong-Du;Kang Hak-Soo;Yoon Yang-Woong
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • 제6권3호
    • /
    • pp.210-216
    • /
    • 2006
  • In the rule based modeling, data partitioning plays crucial role be cause partitioned sub data set implies particular information of the given data set or system. In this paper, we present an empirical study result of the data pattern estimation to find underlying data patterns of the given data. Presented method performs crisp type clustering with given n number of data samples by means of the sequential agglomerative hierarchical nested model (SAHN). In each sequence, the average value of the sum of all inter-distance between centroid and data point. In the sequel, compute the derivation of the weighted average distance to observe a pattern distribution. For the final step, after overall clustering process is completed, weighted average distance value is applied to estimate range of the number of clusters in given dataset. The proposed estimation method and its result are considered with the use of FCM demo data set in MATLAB fuzzy logic toolbox and Box and Jenkins's gas furnace data.

一部 農村地域의 寄生蟲卵 土壤 汚染度에 관한 調査硏究 (A Study on Parasitic Eggs in Soil in Rural Area)

  • Kim, Woong Ki;Chung, Moon Ho
    • 한국환경보건학회지
    • /
    • 제10권1호
    • /
    • pp.67-77
    • /
    • 1984
  • Going to the studies on parasite control carried out in the past. Infection rate among the rural population is contineously decreasing, however, it is still high in Korea. The most important reason for this high infectious rate is the use of manure as fertilizer. This study was aimed at finding the relationship between the infection rate and manure through analizing 83 samples of soil collected from Sa Am-Ri, Kangwon-do in June and July, 1983. The major findings of the study are as follows: 1. 60 cases out of the total sample were carry in at least one or more parasitic eggs, thus revealing 72.3% of positive rate. 2. A total number of 131 parasitic eggs were detected from total sample with an average of 1.6 eggs per 10 g of soil. 3. Asearid eggs more frequently appeared than other parasitic eggs occupying 68.7% or 1.2 eggs in average per 10g of soil. 4. There was revealed positive relationship between infectious rate and frequency of use of manure. (P > 0.05). 5. Infectious rate and average number of parasitic eggs detected were less in the fertilizer mixed with manure and ash than in the soil where only manure was used. (P > 0.05).

  • PDF

Preparation of Monodisperse Melamine-Formaldehyde Microspheres via Dispersed Polycondensation

  • Cheong, In-Woo;Shin, Jin-Sup;Kim, Jung-Hyun;Lee, Seung-Jun
    • Macromolecular Research
    • /
    • 제12권2호
    • /
    • pp.225-232
    • /
    • 2004
  • We have successfully synthesized relatively monodisperse and cross-linked melamine-formaldehyde (M-F) microspheres by dispersed polycondensation and subsequent pH adjustment with serum replacement cleaning. The average particle sizes (equation omitted): weight-average and (equation omitted) : number-average), the polydispersity index (equation omitted), the number of particles N$\_$p/ and the gel content of the M-F microspheres were observed by varying the pH, the surfactant concentration, and the polymerization temperature. We observed that both the pH and the polymerization temperature were predominant factors in determining (equation omitted) and N$\_$p/, but the effect that the temperature and pH had on the gel content ( > 94% for all samples) was negligible. The exponents of the slopes of plots of N$\_$p/ versus pH and surfactant concentration were -10 and 0.6, respectively. Particle nucleation and growth were achieved within short periods; the incessant coagulation occurred even in the presence of surfactants.

비대칭형 슬릿 핀이 적용된 핀-관 열교환기의 습표면 성능 (Air-Side Performance of Fin-and-Tube Heat Exchangers Having Non-Symmetric Slit Fins Under Wet Condition)

  • 김내현
    • 한국산학기술학회논문지
    • /
    • 제16권6호
    • /
    • pp.3698-3707
    • /
    • 2015
  • 본 연구에서는 비대칭형 슬릿 핀 열교환기의 습표면 열전달 및 압력손실에 대하여 실험적으로 검토하였다. 비교를 위하여 널리 사용되는 루버 핀 열교환기에 대한 실험도 수행하였다. 실험범위에서 핀 핏치가 j와 f 인자에 미치는 영향은 크지 않았다. 또한 루버 핀 시료의 j와 f 인자가 슬릿 핀 시료의 값들보다 크게 나타났다. 1열의 경우 평균 j 인자와 f 인자는 27%, 31% 크고, 2열에서는 15%, 30% 크게 나타났다. 슬릿 핀과 루버 핀 모두 열수가 증가하면 j와 f 인자가 감소하였다. 슬릿 핀의 평균 j/f가 루버 핀보다 1열에서 3.4%, 2열에서 11.5% 크게 나타났다. 본 데이터로부터 새로운 상관식을 도출하였다.

전북지방(全北地方) 젖소의 이상유(異常乳) 발생상황(發生狀況)과 원인균(原因菌)에 관한 연구(硏究) (Studies on Incidence and Causative Agents of Abnormal Milk among Dairy Cattle in Jeonbug Area)

  • 김종면;곽택훈
    • 대한수의학회지
    • /
    • 제15권2호
    • /
    • pp.315-320
    • /
    • 1975
  • A total of 364 quarter milk samples of 91 dairy cattle from 4 area around Jeonju in Jeonbug area were examined for infection rate and causative abets of mastitis by the Laboratory Procedures used in the Connecticut Mastitis-Control Program. The results obtained were as follows: 1. One hundred and thirty quarters (35.7%) from 67 cows (73.6%) were found to be infected with mastitis. It was found that 5 (1.37%) of the infected quarters were clinical mastitis and all of the rest were subclinical mastitis (125 quarters). 2. The main causative agents were found to be Staphylococcus aureus (46 quarters), Streptococcus agalactiae (49 quarters), streptococcus disgalactiae (18 quarters), Steptococcus uberis (13 quarters). Corynebacteria, Coliform organisms, Pseudomonas were also occasionally found to be causative organisms. 3. Having examined the number of infection Quarter per head of mastitis dairy cattle samplings, major findings were that the average number of infection quarter to total dairy cattle examined was 1.4 quarters, and that average number of infection quarter to the infected cattle was 1.9 quarters.

  • PDF