• Title/Summary/Keyword: Trials

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Minimum risk point estimation of two-stage procedure for mean

  • Choi, Ki-Heon
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.5
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    • pp.887-894
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    • 2009
  • The two-stage minimum risk point estimation of mean, the probability of success in a sequence of Bernoulli trials, is considered for the case where loss is taken to be symmetrized relative squared error of estimation, plus a fixed cost per observation. First order asymptotic expansions are obtained for large sample properties of two-stage procedure. Monte Carlo simulation is carried out to obtain the expected sample size that minimizes the risk and to examine its finite sample behavior.

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Artificial Intelligent Systems Based on Neural Networks (신경망을 기초로한 인공지능시스템 구현방법)

  • Lee, Gye-Sik
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.46-48
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    • 1992
  • Through the last 20 years' study, it is a well-known fact that symbolic approach has limitations in generating a new concept from given concepts. Hence, neural networks having a role of associative memory based on dynamical activation of neurons attract AI scientists' attention. In this paper, recent trials for combining neural networks and Artificial Intelligent systems are systematically reviewed and a prototype ENEDB(Experimental Neuro Expert DataBase) system built on HP9000/300 workstation is introduced to show the possibility of using the trials for real applications.

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Recent Achievements in Stem Cell Therapy for Pediatric Gastrointestinal Tract Disease

  • Bae, Sun Hwan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.16 no.1
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    • pp.10-16
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    • 2013
  • The field of stem cell research has been rapidly expanding. Although the clinical usefulness of research remains to be ascertained through human trials, the use of stem cells as a therapeutic option for currently disabling diseases holds fascinating potential. Many pediatric gastrointestinal tract diseases have defect in enterocytes, enteric nervous system cells, smooth muscles, and interstitial cells of Cajal. Various kinds of therapeutic trials using stem cells could be applied to these diseases. This review article focuses on the recent achievements in stem cell applications for pediatric gastrointestinal tract diseases.

On a Generalized Inverse Binomial Sampling Plan

  • Bai, Do-Sun;Kim, Seong-In;Lee, Jung-Kyun
    • Journal of the Korean Statistical Society
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    • v.6 no.1
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    • pp.3-20
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    • 1977
  • In many applications one is concerned with repeated Bernoulli trials whose parameter (success probability) is usually unknown and has to be estimated from a sample. The probability distribution and statistical inference on the repeated independent Bernoulli trials have been studied extensively for the cases of fixed sample size sampling plan, and inverse binomial sampling plan in which observations are cotinued until a pressigned number of successes are obtained. See, for example, Haldane, Girschick et al., DeGroot and Johnson and Kotz.

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Estimation of Overflow Probabilities in Parallel Networks with Coupled Inputs

  • Lee, Jiyeon;Kweon, Min Hee
    • Communications for Statistical Applications and Methods
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    • v.8 no.1
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    • pp.257-269
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    • 2001
  • The simulation is used to estimate an overflow probability in a stable parallel network with coupled inputs. Since the general simulation needs extremely many trials to obtain such a small probability, the fast simulation is proposed to reduce trials instead. By using the Cramer’s theorem, we first obtain an optimally changed measure under which the variance of the estimator is minimized. Then, we use it to derive an importance sampling estimator of the overflow probability which enables us to perform the fast simulation.

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Constrained Estimation of the Numbers of Trials in Several Binomial Populations

  • Oh, Myongsik;Lee, Eun-Kyoung
    • Communications for Statistical Applications and Methods
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    • v.7 no.3
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    • pp.699-709
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    • 2000
  • The constrained maximum likelihood estimation of the number of trials in several binomial populations under order restriction, such as simple order, is discussed. The estimation procedure is based on, so called, pool adjacent violators algorithm. Three handy estimators are given and their performances are compared using an artificial example.

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A Comparative Study of Restricted Randomization Methods in Clinicla Trials

  • Huh, Myung-Hoe
    • Journal of the Korean Statistical Society
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    • v.14 no.1
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    • pp.48-55
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    • 1985
  • In clinical trials subjects are avalible sequentially and must be assigned to treatments immediately. Completely randomized procedure for the allocation of treatments to each subject may result in severe imbalance among the number of subjects in treatment groups, especially for small experiments or interim analyses of large experiments. In this study, restricted randomization methods such as biased coin designs (Efron, 1971), permuted block design, and truncated binomial design are compared to teh completely randomized design in the presence of selection and/or accidential bias by Monte Carlo simulations.

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Cases Analysis of Vault "Shirai-Kim Hee Hoon" Technique for Assessing Skill Completeness (도마 Shirai-Kim Hee Hoon 기술의 성공/실패 사례를 통한 융복합 완성도 평가)

  • Song, Joo-Ho;Kim, Dong-Min;Moon, Je-Heon
    • Journal of Digital Convergence
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    • v.13 no.11
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    • pp.441-448
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    • 2015
  • The purpose of the study was to perform a comparative analysis of the success and failure cases to increase the completeness of vault "Shirai-Kim Hee Hoon" technique. The subject of the study was "K" a male gymnast from Korean Artistic Gymnastic National team. The results obtained through the three-dimensional analysis during international as well as practice session are as follows: Firstly, excluding BC, the lead time in each PrF, HC and PoF phases were shorter during successful trials than in failure trials. Secondly, during successful trials, the horizontal and vertical velocity appeared to be higher during taking off, which contributed positively to the leaping motion in the horizontal direction. Thirdly, when compared with successful and failure trials, the body's angular rotation was highly maintained during the takeoff from the spring board followed by larger thigh angular displacement at the vault before actually attempting the backward rotation.

A Review on Randomized Controlled Trials of Herbal Medicine Treatment for Pregnancy-induced Hypertension (임신성 고혈압의 한약 치료에 대한 무작위 대조군 연구의 문헌고찰)

  • Hwang, Su-In;Yoon, Young-Jin;Park, Jang-Kyung
    • The Journal of Korean Obstetrics and Gynecology
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    • v.33 no.3
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    • pp.119-135
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    • 2020
  • Objectives: The purpose of this study is to confirm the effectiveness and safety of herbal medicine treatment for treating pregnancy-induced hypertension. Methods: We searched for randomized controlled trials of pregnancy-induced hypertension treated with herbal medicine, through nine databases. Interventions and results of the selected clinical studies were analyzed. Results: Eleven randomized controlled trials were finally included according to the inclusion and exclusion criteria. Treatment group was treated with herbal medicine alone in two studies, and with herbal medicine and western medicine in nine studies. Control group was treated with western medicine. Taxilli Ramulus (桑寄生) (54.5%) was the most frequently used herb in herbal medicine treatment. In all of eleven studies, treatment group was more effective for pregnancy-induced hypertension than the control group. Conclusions: This study suggested that herbal medicine treatment alone or combined with western medicine treatment could be helpful in improving the therapeutic effect on pregnancy-induced hypertension and reducing side effects as well. However, in order to obtain stronger evidence of herbal medicine treatment for pregnancy-induced hypertension, more high-quality and well-designed randomized controlled trials should be conducted.