• Title/Summary/Keyword: Average sample number

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긴뼈의 형상 평균화 기법 (The Geometric Averaging Technique for Long Bone)

  • 곽대순;이우영;한승호;최광남;김태중
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.177-178
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    • 2006
  • Many authors issued the feature-preserving averaging technique according to positioning and scaling process using landmarks, which represent the geometric characteristics of three dimensional surface models. Such a technique should be done by manual procedure, choosing and marking the landmarks on each bone surface before averaging process. In this study, we produced another averaging technique without having to use such manual procedure, and made averaging models from three dimensional surface data that were reconstructed from computerized tomography images of Digital Korean Project. The bone models were subjected to orthogonal coordinator system. These models were transformed to coincide mass center and to align principal axis. Then, bone models were scaled according to average length data of sample bone models on all axis(x, y, z). After establishing voxellar hexahedron space which contain all sample bone models, we counted the number of overlapping for each voxel. We generated the three dimensional average surface by displaying the yokels that have more overlapping number than boundary number. The boundary number was decided when the average volume of each bone equal to the volume of bone that would be averaged. Using this technique, we can make a feature-preserving averaging volume of bones.

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중남부 삼림 지역에서의 세포성 점균의 출현과 분포 (Cellular Slime Molds in Forest Soils of Central Areas of Korea)

  • 박미아;장남기
    • 아시안잔디학회지
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    • 제10권3호
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    • pp.213-230
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    • 1996
  • A study of occurrence and distribution of cellular slime molds(CSMs) in forest soils of central areas of Korea was carried out. Samples for CSMs isolation were collected from 4 study sites; Mt.Kyeryong, Mt. Taebaek, Mt. Sobaek and Mt. Sokri. In Mt. Kyeryong, six species were found. These were Dictyostelium fasciculatum, D.firmibasis, D. mucoroides, D. minutum, D. brefeldianum and Polysphondylium pallidum. The average number of species isolated at one site was 0.75, and average density(clones /g soil) was 292. The results of soil sample analyses were that the concentration of Pb was higher than any other areas. In Mt. Taebaek, seven species were found; D. fasciculatum, D.firmibasis, D. mucoroides, D. miuutum, P.pallidum. P. violaceum, P. candidum. The average number of species isolated at one site was 2.3,and average density was 1,108. Based on importance values calculated from study sites within each of three elevation ranges, several of the more widely distributed and abundant species have distribution patterns that show a response to elevation. In Mt. Sobaek, eleven species were found. These were D. fasciculatum. D.firmibasis, D. mucoroides, D. miuutum, D. brefeldianum, D. crassicaule,D. deminutivum, D. implicatum, P. pallidum. P. violaceum and P. candidum. The average number of species isolated at one site was 3, and average density was 793. Species diversity appeared to be the highest in this area. In Mt. Sokri, six species were found. These were D. fasciculatum. D. mucoroides, D. minutum, D. purpureum, P. pallidum. and P. violaceum. The average number of species isolated at one site was 2.4 and average density was 858. It was noticeable that D.purpureum were much more comrnonly found in this pinus evergreen forest. Key words: Cellular slime molds(CSMs), Importance value, Elevation, Average number of species, Average density.

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Switching performances of multivarite VSI chart for simultaneous monitoring correlation coefficients of related quality variables

  • Chang, Duk-Joon
    • Journal of the Korean Data and Information Science Society
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    • 제28권2호
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    • pp.451-459
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    • 2017
  • There are many researches showing that when a process change has occurred, variable sampling intervals (VSI) control chart is better than the fixed sampling interval (FSI) control chart in terms of reducing the required time to signal. When the process engineers use VSI control procedure, frequent switching between different sampling intervals can be a complicating factor. However, average number of samples to signal (ANSS), which is the amount of required samples to signal, and average time to signal (ATS) do not provide any control statistics about switching performances of VSI charts. In this study, we evaluate numerical switching performances of multivariate VSI EWMA chart including average number of switches to signal (ANSW) and average switching rate (ASWR). In addition, numerical study has been carried out to examine how to improve the performance of considered chart with accumulate-combine approach under several different smoothing constant and sample size. In conclusion, process engineers, who want to manage the correlation coefficients of related quality variables, are recommended to make sample size as large and smoothing constant as small as possible under permission of process conditions.

Switching properties of CUSUM charts for controlling mean vector

  • Chang, Duk-Joon;Heo, Sun-Yeong
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.859-866
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    • 2012
  • Some switching properties of multivariate control charts are investigated when the interval between two consecutive sample selections is not fixed but changes according to the result of the previous sample observation. Many articles showed that the performances of variable sampling interval control charts are more efficient than those of fixed sampling interval control charts in terms of average run length (ARL) and average time to signal (ATS). Unfortunately, the ARL and the ATS do not provide any information on how frequent a switch is being made. We evaluate several switching properties of two sampling interval Shewhart and CUSUM procedures for controlling mean vector of correlated quality variables.

한국 병원 영양사의 지위 및 업무내용에 관한 실태조사 (A Survey on the Status of Hospital Dititians and their Job Analysis)

  • 옥혜운
    • 대한가정학회지
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    • 제18권1호
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    • pp.15-23
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    • 1980
  • Since the first dietitian was produced in Korean about 15 years ago the Korena Dietetic Association has grown up to have its 8,500 members as of March, 1979. This study was undertaken to survey the status of hospital dietitians and their bob analysis. current practices were learned and the problems identified mainly in such aspects as : 1. Do the hospitals have enough dietitians? 2.What is the administrative position of the dietetics in the hospital? 3. What is the salary level of the dietitians? 4. How professional are the dietitian's daily tasks? How appropriately are the jobs distributed among the dietary employees? and 5. Do the hospital dietetics have their own diet manuals to go by? The findings are : 1. The severly lacking number of dietitians are employed by the hospitals where one dietitian is responsible for the feeding and nutrition education of 171 in-patients on the average. 2. The administrative position of hospital dietetics appears to be low showing administrative position of hospital dietetics appears to be low showing only 45.7% of the sample hospitals recognize their dietetics as the independent department or section. 3. The starting salary of the 4-year college graduate dietitians is 151,450 won which is 89.23-87.26% of the average starting salary for the 4-year college graduates I 1979. The starting salary for the 4-year college graduates in 1979. the starting salary of the 2-year college graduate dietitians is 148,000 won which is 113.9% of the average standard salary for the 2-year college graduates in 1979. 4. The hospital dietitians spend most of their time doing clerical jobs rather than the jobs utilizing higher priority professional skills they ought to perform. the most obvious cause of the problem can be found in the lack of man power for the general clerical jobs in the dietetics which can be proven from the small number of dietary clerks hired by the sample hospitals not even one person (0.45) per hospital on the average. 5. 68.6% of the sample dietetics have some form of compiled diet manuals or guidelines. 11.4% of the samples have diet guide lines ready for the important diets only. 14.3% of the samples do not have any form of diet guideline prepared. 5.7% of the samples use reference diet manuals from other hospitals when need.

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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
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    • 제10권1호
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    • pp.67-77
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    • 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).

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Adjustment of Control Limits for Geometric Charts

  • Kim, Byung Jun;Lee, Jaeheon
    • Communications for Statistical Applications and Methods
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    • 제22권5호
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    • pp.519-530
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    • 2015
  • The geometric chart has proven more effective than Shewhart p or np charts to monitor the proportion nonconforming in high-quality processes. Implementing a geometric chart commonly requires the assumption that the in-control proportion nonconforming is known or accurately estimated. However, accurate parameter estimation is very difficult and may require a larger sample size than that available in practice in high-quality process where the proportion of nonconforming items is very small. Thus, the error in the parameter estimation increases and may lead to deterioration in the performance of the control chart if a sample size is inadequate. We suggest adjusting the control limits in order to improve the performance when a sample size is insufficient to estimate the parameter. We propose a linear function for the adjustment constant, which is a function of the sample size, the number of nonconforming items in a sample, and the false alarm rate. We also compare the performance of the geometric charts without and with adjustment using the expected value of the average run length (ARL) and the standard deviation of the ARL (SDARL).

Exponentially Weighted Moving Average Chart for High-Yield Processes

  • Kotani, Takayuki;Kusukawa, Etsuko;Ohta, Hiroshi
    • Industrial Engineering and Management Systems
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    • 제4권1호
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    • pp.75-81
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    • 2005
  • Borror et al. discussed the EWMA(Exponentially Weighted Moving Average) chart to monitor the count of defects which follows the Poisson distribution, referred to the $EWMA_c$ chart, as an alternative Shewhart c chart. In the $EWMA_c$ chart, the Markov chain approach is used to calculate the ARL (Average Run Length). On the other hand, in order to monitor the process fraction defectives P in high-yield processes, Xie et al. presented the CCC(Cumulative Count of Conforming)-r chart of which quality characteristic is the cumulative count of conforming item inspected until observing $r({\geq}2)$ nonconforming items. Furthermore, Ohta and Kusukawa presented the $CS(Confirmation Sample)_{CCC-r}$ chart as an alternative of the CCC-r chart. As a more superior chart in high-yield processes, in this paper we present an $EWMA_{CCC-r}$ chart to detect more sensitively small or moderate shifts in P than the $CS_{CCC-r}$ chart. The proposed $EWMA_{CCC-r}$ chart can be constructed by applying the designing method of the $EWMA_C$ chart to the CCC-r chart. ANOS(Average Number of Observations to Signal) of the proposed chart is compared with that of the $CS_{CCC-r}$ chart through computer simulation. It is demonstrated from numerical examples that the performance of proposed chart is more superior to the $CS_{CCC-r}$ chart.

Initial sample size problem in the sequential test for the mean of a normal distribution

  • Park, S. C.
    • Journal of the Korean Statistical Society
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    • 제3권1호
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    • pp.3-12
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    • 1974
  • The two-stage sequential test, suggested by Baker [2] for testing hypotheses $H_0:\mu=\mu_0$ and $H_1:\mu=\mu_1$ of $N(\mu,\sigma^2)$ with the unknown $\sigma^2$ would not be amenable for applications unles some cluses on the choice of the first-stage sample size are available. The study in this paper is intended to shed some light on the size of the first-stage sample. An approximate method is used to estimate an optimal initial sample size that minimizes the average sample number. In brief, the optimal size is a strictly monotone decreasing function of the quantity $(\mu_1-\mu_0)/\sigma$. Empirical and simulation results are used to ascertain the negligible effect of possible errors due to approximations and assumptions used.

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A Hybrid Algorithm for Online Location Update using Feature Point Detection for Portable Devices

  • Kim, Jibum;Kim, Inbin;Kwon, Namgu;Park, Heemin;Chae, Jinseok
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권2호
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    • pp.600-619
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    • 2015
  • We propose a cost-efficient hybrid algorithm for online location updates that efficiently combines feature point detection with the online trajectory-based sampling algorithm. Our algorithm is designed to minimize the average trajectory error with the minimal number of sample points. The algorithm is composed of 3 steps. First, we choose corner points from the map as sample points because they will most likely cause fewer trajectory errors. By employing the online trajectory sampling algorithm as the second step, our algorithm detects several missing and important sample points to prevent unwanted trajectory errors. The final step improves cost efficiency by eliminating redundant sample points on straight paths. We evaluate the proposed algorithm with real GPS trajectory data for various bus routes and compare our algorithm with the existing one. Simulation results show that our algorithm decreases the average trajectory error 28% compared to the existing one. In terms of cost efficiency, simulation results show that our algorithm is 29% more cost efficient than the existing one with real GPS trajectory data.