• Title/Summary/Keyword: Meier method

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Comparative Study on the Transport Characteristics of Canalicular Liver Plasma Membrane Vesicles Prepared by Two Different Methods (제조 방법에 따른 간 모세담관막 소포계의 수송 특성 비교)

  • Song, Im-Sook;Chung, Suk-Jae;Shim, Chang-Koo
    • Journal of Pharmaceutical Investigation
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    • v.29 no.1
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    • pp.13-19
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    • 1999
  • Canalicular liver plasma membrane vesicles (cLPM) were prepared according to two different methods (Inoue method and Meier method), and were evaluated for their protein yield, enzyme activity and transport characteristics. No difference was found between the methods in the protein yield (i.e., $0.14{\pm}0.031$ and $0.15{\pm}0.050$ mglg liver for Inoue method and Meier method, respectively). The activity of alkaline phosphatase, a marker enzyme of canalicular membrane, was significantly (P<0.05) higher in the vesicles of Meier method $(3.52{\pm}0.91\;mmol/mg/hr)$than in the vesicles of Inoue method ($2.28{\pm}0.94$ mmol/mg/hr) indicating that more purified cLPM were obtained from Meier method compared with Inoue method. ATP-dependent vesicular uptake of taurocholate and tributylmethylammonium (TBuMA) was observed for vesicles of both methods, and the kinetic parameters responsible for the transport were similar between the vesicles of both methods (for example, $V_{max}:$ 9.72 nmol/mg protein/30sec and $K_m:$ 0.63 mM for Inoue method; $V_{max}:$ 10.1 nmol/mg protein/30sec and $K_m:$ 0.70 mM for Meier method). A pH gradient dependent counter transport of TBuMA was also observed for both vesicles with similar kinetic characteristics. Either the uptake of taurocholate in the absence of ATP or that of TBuMA in the absence of pH gradient, which may represent passive diffusion of respective compound into the vesicles, was more rapid for the vesicles of Meier method than for the vesicles of Inoue method. For example, passive diffusion rate constants $(K_d)$ for TBuMA uptake into the vesicles were 0.00030 and 0.00052\;{\mu}l/mg$ protein/min for the vesicles of Inoue method and Meier method, respectively. It may indicate that more leaky vesicles are obtained form the Meier method compared with the Inoue method. These aspects together with the time necessary to prepare the vesicles (i.e., 8 hr for Inoue method and 23 hr for Meier method) should be considered before selecting an appropriate method for the preparation of cLPM.

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THE EMPIRICAL LIL FOR THE KAPLAN-MEIER INTEGRAL PROCESS

  • Bae, Jong-Sig;Kim, Sung-Yeun
    • Bulletin of the Korean Mathematical Society
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    • v.40 no.2
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    • pp.269-279
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    • 2003
  • We prove an empirical LIL for the Kaplan-Meier integral process constructed from the random censorship model under bracketing entropy and mild assumptions due to censoring effects. The main method in deriving the empirical LIL is to use a weak convergence result of the sequential Kaplan-Meier integral process whose proofs appear in Bae and Kim [2]. Using the result of weak convergence, we translate the problem of the Kaplan Meier integral process into that of a Gaussian process. Finally we derive the result using an empirical LIL for the Gaussian process of Pisier [6] via a method adapted from Ossiander [5]. The result of this paper extends the empirical LIL for IID random variables to that of a random censorship model.

A Study onthe Residential Space by Richard Meier (리챠드 마이어의 주거공간에 관한 연구)

  • 김용립
    • Korean Institute of Interior Design Journal
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    • no.13
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    • pp.78-88
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    • 1997
  • The objective of this study is to analyze the residential space as designed by Richard Meier thereby grasping its main characteristics and historical development. Richard Meier has developed his own peculiar architecture based on Modernism. He has solved problems of modern architecture by combining the form elements of Le Corbusier with Mies van der Rohe's architecture which pursued the beauty of structure and proportiov. Meier's houses, sculpture-like in forms, are characterized by clear distinction and variations of the interior spaces. The clear separation between a large, two-story high living room and a tiny, cozy bedroom securing the privacy, endows the interions with variation and vitality, while simple white walls reveal the good shape of the space. The houses also unfold the diverse spaces one after another as one steps into inside. His interiors, shaped by simple walls and settled functionally, has inherited the rationality in modern architecture. Richard Meier has established his independent working world by applying his own design method and languages based on the rationality in Modernism.

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Reliability Analysis under the Competing Risks (경쟁적 위험하에서의 신뢰성 분석)

  • Baik, Jaiwook
    • Journal of Applied Reliability
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    • v.16 no.1
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    • pp.56-63
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    • 2016
  • Purpose: The purpose of this study is to point out that the Kaplan-Meier method is not valid to calculate the survival probability or failure probability (risk) in the presence of competing risks and to introduce more valid method of cumulative incidence function. Methods: Survival analysis methods have been widely used in biostatistics division. However the same methods have not been utilized in reliability division. Especially competing risks cases, where several causes of failure occur and the occurrence of one event precludes the occurrence of the other events, are scattered in reliability field. But they are not noticed in the realm of reliability expertism or they are analysed in the wrong way. Specifically Kaplan-Meier method which assumes that the censoring times and failure times are independent is used to calculate the probability of failure in the presence of competing risks, thereby overestimating the real probability of failure. Hence, cumulative incidence function is introduced and sample competing risks data are analysed using cumulative incidence function and some graphs. Finally comparison of cumulative incidence functions and regression type analysis are mentioned briefly. Results: Cumulative incidence function is used to calculate the survival probability or failure probability (risk) in the presence of competing risks and some useful graphs depicting the failure trend over the lifetime are introduced. Conclusion: This paper shows that Kaplan-Meier method is not appropriate for the evaluation of survival or failure over the course of lifetime. In stead, cumulative incidence function is shown to be useful. Some graphs using the cumulative incidence functions are also shown to be informative.

A Study on the Characteristics of Exhibition Space Planning in Museums Desinged by Richard Meier (리차드 마이어의 뮤지엄건축 전시공간구성 특성에 관한 연구)

  • Lee Sung-Hoon;Park Yong-Hwan
    • Korean Institute of Interior Design Journal
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    • v.15 no.4 s.57
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    • pp.97-105
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    • 2006
  • Richard Meier has earned his recognition by developing his unique design approach and keeping consistency in design concept in museum architecture over the years of his practice. The purpose of this study is finding common characteristics of the exhibition space spatial organization based on actual site visit analysis. This study will mainly focus on the museums Richard Meier designed between 1979, which is the year he started, until 1997 which is the year Getty Museum opened. For the purpose of this study, Museum of Applied Art, Frankfurt(1979-85), High Museum of Art, Atlanta(1980-83), Museum of Contemporary Art, Barcelona(1987-95), and The J.Paul Getty Museum(1984-1997) have been selected for analysis. This study will reveal fundamental characteristics of Richard Meier's architectural philosophy through his early residential projects and give background information of the 'white architecture' Close analysis will continue by reviewing four museums selected specifically for this study and focus more from the point of issues such as; 1)applying various axis in space programming, 2)symbolic significance of exhibition space, 3)hierarchy of each space, 4)design elements and characteristics of the exhibition space. Furthermore, quantitative research on exhibition space organization will be done by Space Syntax theory method. The result of the study will be a significant data in designing a modern museum.

Surgical treatment of Metastatic Lung Cancer (전이성 폐암에 대한 외과적 치험)

  • 이종호;임용택;신용철;정승혁;김병열
    • Journal of Chest Surgery
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    • v.32 no.1
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    • pp.27-31
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    • 1999
  • Background: In spite of the development of chemotherapy, prognosis of metastatic lung cancer was poor. On the other hand, surgical intervention has proven itself to bring out superior results, therefore more operations are being praticed based on this superiority against chemotherapy and other modalities on metastatic lung cancer. Material and Method : We analyzed the surgical cases performed from 1983 to 1997 on 17 cases and estimated 5 year survival rate using Kaplan-Meier method. Result: Average age was 42.8, ratio between male and female was 10:7. We had 8 single lobe resections,3 pneumonectomies,1 wedge resection,2 bilobectomy and 3 cases of lobar resection with wedge resection. 5 deaths have occured and among the 5, 3 patients were caused by recurrence of ca. The remaining 12 patients are being followed up in OPD basis among these, 3 recurrence were observed and 9 are still free of cancer. The average survival time was 40.5 months and 5 year survival rate obtained through the Kaplan-Meier method was 60.4%. Conclusion: Even though we are a bit short of cases, we recommend that a thoracic surgeon approach this disease through a surgical method as possibly as he could.

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Smoothing Kaplan-Meier estimate using monotone support vector regression (단조 서포트벡터기계를 이용한 카플란-마이어 생존함수의 평활)

  • Hwang, Changha;Shim, Jooyong
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.6
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    • pp.1045-1054
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    • 2012
  • Support vector machine is known to be the very useful statistical method in classification and nonlinear function estimation. In this paper we propose a monotone support vector regression (SVR) for the estimation of monotonically decreasing function. The proposed monotone SVR is applied to smooth the Kaplan-Meier estimate of survival function. Experimental results are then presented which indicate the performance of the proposed monotone SVR using survival functions obtained by exponential distribution.

Conditional Bootstrap Methods for Censored Survival Data

  • Kim, Ji-Hyun
    • Journal of the Korean Statistical Society
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    • v.24 no.1
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    • pp.197-218
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    • 1995
  • We first consider the random censorship model of survival analysis. Efron (1981) introduced two equivalent bootstrap methods for censored data. We propose a new bootstrap scheme, called Method 3, that acts conditionally on the censoring pattern when making inference about aspects of the unknown life-time distribution F. This article contains (a) a motivation for this refined bootstrap scheme ; (b) a proof that the bootstrapped Kaplan-Meier estimatro fo F formed by Method 3 has the same limiting distribution as the one by Efron's approach ; (c) description of and report on simulation studies assessing the small-sample performance of the Method 3 ; (d) an illustration on some Danish data. We also consider the model in which the survival times are censered by death times due to other caused and also by known fixed constants, and propose an appropriate bootstrap method for that model. This bootstrap method is a readily modified version of the Method 3.

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Comparison of the Kaplan-Meier and Nelson Estimators using Bootstrap Confidence Intervals

  • Cha, Young Joon;Lee, Jae Man
    • Journal of Korean Society for Quality Management
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    • v.23 no.4
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    • pp.42-51
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    • 1995
  • The bootstrap confidence intervals are a computer-based method for assigning measures of accuracy to statistical estimators. In this paper we examine the small sample behavior of the Kaplan-Meier and Nelson-type estimators for the survival function using the bootstrap and asymptotic normal-theory confidence intervals. The Nelson-type estimator is nearly always better than the Kaplan-Meier estimator in the sense of achieved error rates. From the point of confidence length, the reverse is true. Also, we show that the bootstrap confidence intervals are better than the asymptotic normal-theory confidence intervals in terms of achieved error rates and confidence length.

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Regression Quantiles Under Censoring and Truncation

  • Park, Jin-Ho;Kim, Jin-Mi
    • Communications for Statistical Applications and Methods
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    • v.12 no.3
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    • pp.807-818
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    • 2005
  • In this paper we propose an estimation method for regression quantiles with left-truncated and right-censored data. The estimation procedure is based on the weight determined by the Kaplan-Meier estimate of the distribution of the response. We show how the proposed regression quantile estimators perform through analyses of Stanford heart transplant data and AIDS incubation data. We also investigate the effect of censoring on regression quantiles through simulation study.