• 제목/요약/키워드: New Trial

검색결과 860건 처리시간 0.026초

고성능 콘크리트 배합 설계에서의 유전자 알고리즘의 적용 (Genetic Algorithm in Mix Proportioning of High -Performance Concrete)

  • 임철현;윤영수;이승훈;손유신
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.551-556
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    • 2002
  • High-performance concrete is defined as concrete that meets special combinations of performance and uniformity requirements that cannot always be achieved routinely using conventional constituents and normal mixing, placing, and curing practices. Ever since the term high-performance concrete was introduced into the industry, it had widely used in large-scale concrete construction that demands high-strength, high-flowability, and high-durability. To obtain such performances that cannot be obtained from conventional concrete and by the current method, a large number of trial mixes are required to select the desired combination of materials that meets special performance. In this paper, therefore, using genetic algorithm which is a global optimization technique modeled on biological evolutionary process-natural selection and natural genetics-and can be used to find a near optimal solution to a problem that may have many solutions, the new design method for high-performance concrete mixtures is suggested to reduce the number of trial mixtures with desired properties in the field test. Experimental and analytic investigations were carried out to develop the design method for high-performance concrete mixtures and to verify the proposed mix design.

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Understanding noninferiority trials

  • Hahn, Seokyung
    • Clinical and Experimental Pediatrics
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    • 제55권11호
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    • pp.403-407
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    • 2012
  • Noninferiority trials test whether a new experimental treatment is not unacceptably less efficacious than an active control treatment already in use. With continuous improvements in health technologies, standard care, and clinical outcomes, the incremental benefits of newly developed treatments may be only marginal over existing treatments. Sometimes assigning patients to a placebo is unethical. In such circumstances, there has been increasing emphasis on the use of noninferiority trial designs. Noninferiority trials are more complex to design, conduct, and interpret than typical superiority trials. This paper reviews the concept of noninferiority trials and discusses some important issues related to them.

Estimation of Maximal Tolerated Dose in Sequential Phase I Clinical Trials

  • Park, In-Hye;Song, Hae-Hiang
    • Communications for Statistical Applications and Methods
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    • 제6권2호
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    • pp.543-564
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    • 1999
  • The principal aim of a sequential phase I clinical trial in which the toxicity reponses of a group of patient(s) determine the dose level of the next patient(s) group is to estimate the maximal tolerated dose(MTD) of a new drug, In this paper we compared with a simulation study the performance of the MTD estimates that are determined by a stopping rule in a design and also those that are determined by analyzing the data after a clinical trial is terminated. To the latter belong the mean median mode and maximum likelihood estimates. For the Standard Methods the stopping rule MTD is quite inefficient but the median MTD has a best efficiency and is robust with respect to the three different toxicity curves. The problem of non-convergence of MLE MTD is severe. A more improved MTD estimate is produced by combining the advantages of the various MTD estimates and its efficiency is better than the single median MTD estimate especially for the toxicity curve of an unlucky choice of dose levels. The simulation results suggest that simple types of phase I designs can be combined with relatively standard analytic techniques to provide a more efficient MTD estimate.

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전자해도 실선시험에 관한 연구 (Study on the ENC Sea Trial Plan)

  • 서상현;이희용
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 1998년도 추계학술대회논문집:21세기에 대비한 지능형 통합항만관리
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    • pp.85-95
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    • 1998
  • ECDIS, highlihgted as a new technology for the navigation safety, could replace the paper charts in the bridge and make the more safe navigation possible. For the marines to use the ECDIS, the infrastructrue of the ENC production and distribution, the development of IMO compliant ECDIS, the training program for the ECDIS usage and related matters are thought as the key points to be solved. Also it is necessary for the ECDIS usage and related maters are thought as the key point to be solved. Also it is necessary for the related groups, such as ECDIS manufactures, users, ENC producers, the to be involved in developing the national infrastructure altogether to promote the ECDIS usage. Upon these background, the Korean ENC pilot project was introduced and the comparison study of the SHARED project coordinated by MPA(Maritime Port Authority, Singapore) and the Canadan Pilot project has been done. With such a analysis, the Korean ENC sea trial test plan is presented.

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Overview of RCT for Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis

  • Son, Chang-Gue
    • 대한한의학회지
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    • 제32권3호
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    • pp.44-49
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    • 2011
  • Objective: This study aimed to get information on the current status of therapies to date for non-alcoholic fatty liver disease (NAFLD), including non-alcoholic steatohepatitis (NASH). Methods: All randomized clinical controlled trial (RCT)-derived papers for NAFLD or NASH were reviewed via PubMed Database. Results: 39 RCTs met the review criteria, of which 15 and 24 papers were for NAFLD and NASH, respectively. 83% of the papers were released since 2006, and 30 studies were conducted for western medicines, antioxidants and lifestyle intervention whereas nine trials were done using herbal medicine or acupuncture which showed positive outcome. Conclusions: NAFLD and NASH are new epidemic disorders which can be a target of traditional Oriental medicine. This study will be helpful for the Oriental medicine-based strategies or therapeutic development for them.

Anti-ageing Effects of Cysteine-containing Peptides Derived from Milk Whey Protein

  • Dudek, Steffi;Clark, David C.
    • Journal of Dairy Science and Biotechnology
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    • 제23권2호
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    • pp.107-114
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    • 2005
  • The trend towards ageing populations has been observed over many years in Europe and the US but has accelerated significantly in developed countries in Asia including Japan and South Korea. In the latter country the elderly population (65+) has increased 5-fold between 1960 and 2000 and this group will comprise 40% of the population by 2050. This creates a new socio-economic group with specific demands and considerable spending power. As ageing occurs a range of changes occur in the body that can be moderated by adjustments in nutrition. A significant body of evidence points to changes in the balance of glutathione synthesis and utilisation as people age. Glutathione is tile most important natural anti-oxidant of the body and the amounts present can become limited by available cysteine in the diet. A cysteine-enriched peptide product, Cysteine Peption$^{TM}$ has been developed by DMV International for dietary supplement and food applications. A qualitative consumer trial has indicated benefits including improved sleep and more energy. Animal and clinical trial will be described that provide indications on bioavailability and possible mechanisms of action of Cysteine Peption$^{TM}$ with particular focus on the ageing population.

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A HYBRID METHOD FOR NCP WITH $P_0$ FUNCTIONS

  • Zhou, Qian;Ou, Yi-Gui
    • Journal of applied mathematics & informatics
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    • 제29권3_4호
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    • pp.653-668
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    • 2011
  • This paper presents a new hybrid method for solving nonlinear complementarity problems with $P_0$-functions. It can be regarded as a combination of smoothing trust region method with ODE-based method and line search technique. A feature of the proposed method is that at each iteration, a linear system is only solved once to obtain a trial step, thus avoiding solving a trust region subproblem. Another is that when a trial step is not accepted, the method does not resolve the linear system but generates an iterative point whose step-length is defined by a line search. Under some conditions, the method is proven to be globally and superlinearly convergent. Preliminary numerical results indicate that the proposed method is promising.

혈관성 치매 치료 한약물 임상연구 고찰 (Review of Clinical Trials about Herbal Medicine for Vascular Dementia)

  • 김가나;조성훈
    • 동의신경정신과학회지
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    • 제23권4호
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    • pp.37-48
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    • 2012
  • Objectives : The purpose of this study is to investigate the frequently used herbal materials among herbal prescription for vascular dementia. Methods : Every article relevant to vascular dementia was initially obtained from a Korean database and PubMed. Keywords searched were 'vascular dementia', 'herbal medicine' and 'human'. Results : Clinical study, which vascular dementia were treated with herbal medicine, were 12. Among these 12 articles, 6 were case study, 1 was Controlled Clinical Trial and 5 were Ramdomized Controlled Trial (RCT). High frequently used herbal materials were Ginseng Radix (9 times), Cnidii Rhizoma (8 times), Glycyrrhizae Radix, Citri Pericarpium, Astragali Radix and Angelicae Gigantis Radix (6 times). Conclusions : We could know frequent-used herbal medicine for vascular dementia. To be aware of the frequently used herbal medicine for vascular dementia can be helpful in adding herbal materials to prescription in a clinical treatment and development of new drugs.

시스템 식별법을 이용한 선박의 횡동요 계수 추정 (Estimation of Roll Related Coefficients of a Ship by Using the System Identification Method)

  • 윤현규;손남선
    • 대한조선학회논문집
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    • 제41권4호
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    • pp.53-58
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    • 2004
  • When a fast container ship or a naval vessel is turning, comparable roll motions occur. Therefore, roll effect has to be considered in the horizontal equations of motion of the ship to predict the maneuverability well. In this thesis, a new method to determine a roll model structure and estimate its coefficients by applying the system identification technique to the data of sea trial tests was proposed. The simulation results from the estimated roll model were well consistent with the true one in spite of the difference between the estimated and the true model structures of roll hydrodynamic moment.