• Title/Summary/Keyword: block sample

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Model Classification of Quality Statistics Using Block Repeated Measures (블록 반복측정을 이용한 품질통계 모형의 유형화)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.9 no.3
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    • pp.165-171
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    • 2007
  • Dependent models in quality statistics are classified as serially autocorrelated model, multivariate model and dependent sample model. Dependent sample model is most efficient in time and cost to obtain samples among the above models. This paper proposes to implement parametric and nonparametric models into production system depended on demand pattern. Nonparametric models have distribution free and asymptotic distribution free techniques. Quality statistical models are classified into two categories ; the number of dependent sample and the type of data. The type of data consists of nominal, ordinal, interval and ratio data. The number of dependent sample divides into 2 samples and more than 3 samples.

Estimation of long memory parameter in nonparametric regression

  • Cho, Yeoyoung;Baek, Changryong
    • Communications for Statistical Applications and Methods
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    • v.26 no.6
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    • pp.611-622
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    • 2019
  • This paper considers the estimation of the long memory parameter in nonparametric regression with strongly correlated errors. The key idea is to minimize a unified mean squared error of long memory parameter to select both kernel bandwidth and the number of frequencies used in exact local Whittle estimation. A unified mean squared error framework is more natural because it provides both goodness of fit and measure of strong dependence. The block bootstrap is applied to evaluate the mean squared error. Finite sample performance using Monte Carlo simulations shows the closest performance to the oracle. The proposed method outperforms existing methods especially when dependency and sample size increase. The proposed method is also illustreated to the volatility of exchange rate between Korean Won for US dollar.

A Method for Determining Molecular Weights of Block Copolymers by Gel Permeation Chromatography

  • Sohn, Jeong-In;Ree, Tai-Kyue
    • Bulletin of the Korean Chemical Society
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    • v.5 no.4
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    • pp.140-145
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    • 1984
  • A theory is given for determining the molecular weights of block copolymers from the experimental elution volume in GPC. Interaction effect between a sample of block copolymer and a column packing material as well as the size effect are separately considered for the first time applying the partial exclusion mechanism proposed by Dawkins. The molecular weight determination shows 6${\%}$ standard-deviation from the molecular weights measured by an osmometric method for eight block copolymers, which is much more improved result than other methods, e.g., the universal plot method (13 ${\%}$) and the Runyon's method (12 ${\%}$). The reason which explains the better result is that our theory takes into account the interaction effect correctly.

MR ANGIOGRAPHY USING THE COMPOSITE [$90^{\circ}-{\tau}-180^{\circ}-2{\tau}-180^{\circ}-{\tau}$] SEQUENCE (복합 [$90^{\circ}-{\tau}-180^{\circ}-2{\tau}-180^{\circ}-{\tau}$ 시이퀸스를 이용한 핵자기 공명 혈관 조영술)

  • Kim, J.H.;Lee, K.D.;Jeon, H.H.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1989 no.05
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    • pp.35-37
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    • 1989
  • A new MR angiography technique using a composite sequence for the suppression of static sample signals is proposed and verified with experiments. When the composite [$90^{\circ}-{\tau}-180^{\circ}-2{\tau}-180^{\circ}-{\tau}$] sequence is applied, the large signal from the static sample is sufficiently suppressed but the signal from fresh inflow sample of which amplitude. is observed without suppression. These properties are appropriate for angiographic applications. In this paper, a modified line scan method (Block line scan angiography) incorporated with the composite [$90^{\circ}-{\tau}-180^{\circ}-2{\tau}-180^{\circ}-{\tau}$] sequence is used to obtain flow-only images, i.e., angiograms. The block line scan method improves the resolution in the flow-direction at the expense of imaging time. With the composite sequence, there is no need for subtraction procedure as in the most conventional angiographic methods. Experimental results for a phantom and a normal volunteer with KAIS 2.0 Tesla MRI system are shown.

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Rank tests for Conparing several treatments with a control in a Randomized Block experiment

  • Park, Sang-Gue;kim, Jeong-il;Lee, Eun-Koo
    • Journal of Korean Society for Quality Management
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    • v.19 no.1
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    • pp.16-27
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    • 1991
  • Propose three rank tests based on different kinds of ranking methods for comparing several treatments with a control in a randomized block experiment. Monte Carlo power simulation study is examined in some small sample sizes and configurations to recommend a better test for applications.

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A Study on Thermal Performance of Micro Channel Water Block for Computer CPU Cooling (컴퓨터 CPU 냉각용 미세채널 워터블록의 열성능에 관한 연구)

  • Kwon, Oh-Kyung;Choi, Mi-Jin;Cha, Dong-An;Yun, Jae-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.10
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    • pp.776-783
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    • 2008
  • The object of this paper is to study on the thermal performance of a micro channel water block for computer CPU cooling. The effects of liquid flow rate, micro channel width and height on the thermal performances of water block are investigated experimentally. The water block was fabricated Al and machined with a micro milling. The water block consisted of rectangular micro channels 0.5 to 0.9 mm width and 1.5 to 4.5 mm height. The experiments were conducted using deionized water, over a liquid flow rate ranging from 0.2 to 2.0 kg/min. The base temperature and thermal resistance decrease with increasing of liquid flow rate. The increase of a channel height is more effective on the thermal resistance than the decrease of a channel width. At the flow rate of 0.7 kg/min, input power of 100 W, the base temperature and thermal resistance of sample 6 is $33^{\circ}C$ and $0.13\;^{\circ}C/W$ respectively.

The Variation of Nutural Population of Pinus densiflora S. et Z. in Korea -Change of variance due to number of family as sample size to affirm the population and family variations- (소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(IV) -집단간(集團間) 및 가계간분산(家系間分散) 추정(推定)에 영향하는 가계수(家系數)에 대하여-)

  • Yim, Kyong Bin;Kwon, Ki Won;Lee, Kyong Jae
    • Journal of Korean Society of Forest Science
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    • v.35 no.1
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    • pp.39-46
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    • 1977
  • In the analysis of variance between population and between individual trees (families), the fluctuation of values of variances due to sample size, (number of family) was analysed by two different designs, i.e. 2-level nested design with equal sample size and randomized complete block design. The variables were seedling heights and root calipers of 1-0 and 1-1 seedlings of Pinus densiflora S. et Z. The details of three natural stands and their progeny characters were presented in previous reports. 1. In nested design analysis. increase of sample size resulted the decrease of F-values among families in general, however, the F-values among populations showen the increasing tendency. The smaller the sample size, the larger the F-values fluctuation was resulted in general. At the point of beyond sample size 10, however, the fluctuation become to be stabilized. The F-value fluctuation seemed to be more in the case of analysis with random sampling method than with sequentially accumulated sampling method. And also such a tendency was more obvious in smaller sample size than in large one. 2. In R.C.B.D. analysis, the sample size to affirm the family variation was smaller than that for population variations.

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In Situ PCR on the Glass Slide Using the Conventional DNA Thermal Cycler (기존의 핵산증폭기를 사용한 유리슬라이드상에서의 원위치 중합효소 연쇄반응)

  • 오정균;장진수;이재영
    • Korean Journal of Microbiology
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    • v.39 no.3
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    • pp.197-200
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    • 2003
  • In order to establish effective in situ PCR on the glass slide using the conventional DNA thermal cycler, several parameters should be considered. These include full accessibility of PCR reagents into the cells, prevention of diffusing PCR products out of the cells, loss of PCR reagents by nonspecific adherence onto the glass slide, dryness of PCR reagents by heat, and heat conductivity from the heat block to the glass slide. Especially, to guarantee the full accessibility of PCR reagents to sample, relatively higher concentration of PCR reagents (particularly 4.5 mM of $Mg^{++}$) was required while 5 to 10 units/50 ${\mu}l$ reaction of Taq enzyme was enough as long as the step of pre-PCR incubation was included. Dryness of sample was prevented by addition of distilled water into the empty slots in the heat block, thereby providing the reproducible temperature-time profile of PCR. Observed temperature was lower than the programmed temperature by 3 to $4^{\circ}C$.

A Study on the Water-Purification Characteristics of Bio-Composite Planting Blocks (바이오 복합 식생블록의 수질정화 특성 연구)

  • Kim, Young-Ik;Yeon, Kyu-Seok;Choi, Joong-Dae;Kim, Ki-Sung;Seo, Ji-Yeon;Kim, Yong-Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.53 no.2
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    • pp.75-82
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    • 2011
  • This study was performed to evaluate the water purification properties of bio-composites planting blocks using oyster shell and effective microorganism that have high absorption ability of heavy metals and organics to develop environmentally friendly river embankment technique contained various factors such as oyster shells, effective microorganism, porous concrete and planting embankment block. To maximize greening effect, the seeds were arbitrarily sown. In addition, in order to analyze the effect of water quality purification after the planting, the samples were collected from each designated zone 1, 7 and 30 days after steeping in water. Then, the samples were analyzed in terms of seven test items such as SS, BOD, COD, T-N, T-P, pH, etc. on the basis of the test method for water pollution. The following conclusions were reached from the test result. As a result of analysis for water quality purification for the concrete block containing the effective microorganism, it was found that the values for SS, BOD, T-N and T-P for the sample taken after 30 days were lower than the initial values, which indicated that the water purification effect had been created. The result of the water quality purification analysis for the concrete block containing oyster shell showed that the values for SS, BOD, COD and T-P for the sample taken after 30 days were lower than the initial values which also indicated that it had been effective in water quality purification.