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Systems Science and Mathematical Sciences 1991年第4期4卷 289-301页

作者：张健 Institute of Systems Science Academia SinicaBeijing 100080China

In this paper the bootstrap theories,which are based on the author’s former paper,ofM-typ eprincipal components and dispersion matrices and M-type PP tests for multivariate locationand scale are *** bootstrap confide... 详细信息

关键词： Bootstrap confidence sets eigenvalues and eigenvectors dispersion matrices projection pursuit(PP) bootstrap tests

Model Aerodynamic tests with a Wire-driven Parallel Suspension System in Low-speed Wind Tunnel

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Chinese Journal of Aeronautics 2010年第4期23卷 393-400页

作者：肖扬文林麒郑亚青梁斌厦门大学航空系厦门361005 华侨大学机电及自动化学院泉州362021 中国电信深圳分公司深圳518034

Owing to the advantages of wire-driven parallel manipulator, a new wire-driven parallel suspension system for airplane model in low-speed wind tunnel is constructed, and the methods to measure and calculate the aerodynamic parameters of the airplane model are studied. In detail, a static model of the wire-driven parallel suspension is analyzed, a mathematical model for describ- ing the aerodynamic loads exerted on the scale model is constructed and a calculation method for obtaining the aerodynamic parameters of the model by measuring the tension of wires is presented. Moreover, the measurement system for wire tension and its corresponding data acquisition system are designed and built. Thereafter, the wire-driven parallel suspension system is placed in an open return circuit low-speed wind tunnel for wind tunnel tests to acquire data of each wire tension when the airplane model is at different attitudes and different wind speeds. A group of curves about the parameters for aerodynamic load exerted on the airplane model are obtained at different wind speeds after the acquired data are analyzed. The research results validate the feasibility of using a wire-driven parallel manipulator as the suspension system for low-speed wind ttmnel tests.

关键词： wire-driven parallel manipulators low-speed wind tunnel suspension system aerodynamic loads tests

Thermal analysis and tests of W/Cu brazing for primary collimator scraper in CSNS/RCS

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Nuclear Science and Techniques 2017年第4期28卷 19-23页

作者： Jie-Bing Yu Jia-Xin Chen Ling Kang Jie-Feng Wu Yi-Qing Zou Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Dongguan Neutron Science Center Dongguan 523803 China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031 China

To the transverse beam collimation system in a rapid cycling synchrotron,an important component is the primary collimator,which improves emittance of the beam halo particles such that the particles outside the predefined trajectory can be absorbed by the secondary *** the material properties and power deposition distribution,the beam scraper of the primary collimator is a0.17 mm tungsten foil on a double face-wedged copper block of 121.5 mm x 20 *** heat is transferred to the outside by a φ34 mm copper *** this paper,for minimizing brazing thermal stress,we report our theoretical analysis and tests on brazing the tungsten and copper materials which differ greatly in *** show that the thermal stress effect can be controlled effectively by creating stress relief grooves on the copper block and inserting a tungsten transition layer into the copper *** innovation contributes to the successful R&D of the primary *** this study may be of help for working out a brazing plan of similar structures.

关键词： Scraper of primary collimator of CSNS/RCS W/Cu brazing Thermal analysis Brazing tests

tests for Two-Sample Location Problem Based on Subsample Quantiles

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Open Journal of Statistics 2014年第1期4卷 70-74页

作者： Parameshwar V. Pandit Savitha Kumari S. B. Javali Department of Public Health Dentistry SDM College of Dental Sciences and Hospital Dharwad India Department of Statistics Bangalore University Bangalor India Department of Statistics SDM College Ujire India

This paper presents a new class of test procedures for two-sample location problem based on subsample quantiles. The class includes Mann-Whitney test as a special case. The asymptotic normality of the class of tests proposed is established. The asymptotic relative performance of the proposed class of test with respect to the optimal member of Xie and Priebe (2000) is studied in terms of Pitman efficiency for various underlying distributions.

关键词： U-Statistic Class of tests Two-Sample Location Problem Asymptotic Normality Pitman ARE Subsample Quantiles

On Some Critical Issues of the LAGEOS-Based tests of the Lense-Thirring Effect

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Journal of Modern Physics 2011年第4期2卷 210-218页

作者： Lorenzo Iorio 不详

We summarize some critical issues pertaining the tests of the general relativistic Lense-Thirring effect performed by I. Ciufolini and coworkers in the gravitational field of the Earth with the geodetic satellites LAG... 详细信息

关键词： Experimental Studies of Gravity Experimental tests of Gravitational Theories Satellite Orbits Harmonics of the Gravity Potential Field Geopotential Theory and Determination

Genotoxicity tests and Their Contributions in Aquatic Environmental Research

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Journal of Environmental Protection 2014年第14期5卷 1391-1399页

作者： Alaa G. M. Osman Department of Zoology Faculty of Science Al-Azhar University (Assiut Branch) Assiut Egypt Department of Ecophysiology and Aquaculture Leibniz-Institute of Freshwater Ecology and Inland Fisheries Berlin Germany

As many chemicals with genotoxic potential are emitted to surface water, genotoxicity tests are gaining importance which led to the development of several techniques to detect directly DNA damage. The relevance of detecting the genotoxic risks associated with water pollution was firstly perceived in the late 1970s. Since that time several tests have been developed for evaluating DNA alterations in aquatic animals. These tests rely on the premise that any changes to DNA may have long-lasting and profound consequences. Sister chromatid test, chromosome aberrations, comet assay, and micronucleus test are currently the most widely employed methods to detect DNA lesions in ecotoxicology. Chromosomal aberration and sister chromatid exchanges are time consuming, resource intensive and require proliferating cell population. Hence, Comet assay and Micronucleus test as cost effective and more sensitive test systems have now been introduced for assessing the genotoxicity of chemicals. This review presents a synthesis of the state of the art in the methodologies of comet assay and micronucleus test and their contributions in aquatic environmental research. The text explores the latest knowledge and thinking on these very important approaches for the assessment of environmental health, management, and conservation. The primary concern of the present review is the measurement of genotoxic potential in aquatic organisms under field and laboratory conditions, where effects of chemicals at different levels of biological organization can be examined.

关键词： Aquatic Environmental Research Genotoxicity tests Aquatic Organisms Comet Assay Micronucleus Test

Asymptotic Results for Goodness-of-Fit tests Using a Class of Generalized Spacing Methods with Estimated Parameters

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Open Journal of Statistics 2018年第4期8卷 731-746页

作者： Andrew Luong école d’actuariat Université Laval Ste Foy Québec Canada

A class of pseudo distances is used to derive test statistics using transformed data or spacings for testing goodness-of-fit for parametric models. These statistics can be considered as density based statistics and expressible as simple functions of spacings. It is known that when the null hypothesis is simple, the statistics follow asymptotic normal distributions without unknown parameters. In this paper we emphasize results for the null composite hypothesis: the parameters can be estimated by a generalized spacing method (GSP) first which is equivalent to minimize a pseudo distance from the class which is considered;subsequently the estimated parameters are used to replace the parameters in the pseudo distance used for estimation;goodness-of-fit statistics for the composite hypothesis can be constructed and shown to have again an asymptotic normal distribution without unknown parameters. Since these statistics are related to a discrepancy measure, these tests can be shown to be consistent in general. Furthermore, due to the simplicity of these statistics and they come a no extra cost after fitting the model, they can be considered as alternative statistics to chi-square statistics which require a choice of intervals and statistics based on empirical distribution (EDF) using the original data with a complicated null distribution which might depend on the parametric family being considered and also might depend on the vector of true parameters but EDF tests might be more powerful against some specific models which are specified by the alternative hypothesis.

关键词： Density Based tests EDF tests Anderson-Darling Statistic Hellinger Distance Statistic Pseudo-Distance Maximum Spacing Method

Twofold Vlidation of NMET Writing tests

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语言与文化研究 2007年第1期1卷 40-45页

作者： Foreign Language Department,Beijing WuZi University Wan Jingjing Foreign Language Department Beijing WuZi University

This article takes the validation of NMET writing tests as a point of penetration to examine meticulously and fastidiously whether tests of this kind influence on a national basis can test what it is supposed to ***,I shall deal with this issue in a twofold manner,*** validity and content ***,I also aim to produce findings that could help to guide revisions and promote effectiveness of *** the quantifying and categorizing data collected,I eventually came up with four tables to clearly demonstrate the twofold validity of NMET writing tests.

关键词： NMET writing tests face validity content validity

Data Consistency tests through the Use of Neural Networks and Virial Equation. Application of the Proposed Methodology to Critical Study of Density Data

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Open Journal of Physical Chemistry 2011年第3期1卷 61-69页

作者： Abdeslam Hassen Meniai Serge Laugier Hakim Madani Dominique Richon I2m - Umr 5295 Cnrs / Enscbp Laboratoire d"etudes des Systemes Energetiques Industriels Universite de Batna Laboratoire de l"Ingenierie des Procedes d"Environnement Universite Mentouri Constantine

This paper focuses on a very important point which consists in evaluating experimental data prior to their use for chemical process designs. Hexafluoropropylene P, ρ, T data measured at 11 temperatures from 263 to 362 K and at pressures up to 10 MPa have been examined through a consistency test presented herein and based on the use of a methodology implying both neural networks and Virial equation. Such a methodology appears as very powerful to identify erroneous data and could be conveniently handled for quick checks of databases previously to modeling through classical thermodynamic models and equations of state. As an application to liquid and vapor phase densities of hexafluoropropylene, a more reliable database is provided after removing out layer data.

关键词： Consistency tests Hexafluoropropylene Neural Networks Vibrating Tube Densimeter Virial Equation

Computational Precision of the Power Function for Conditional tests of Assumptions of the Rasch Model

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Open Journal of Statistics 2018年第6期8卷 873-884页

作者： Clemens Draxler Jan Philipp Nolte UMIT—The Health and Life Sciences University Hall in Tirol Austria

Draxler and Zessin [1] derived the power function for a class of conditional tests of assumptions of a psychometric model known as the Rasch model and suggested an MCMC approach developed by Verhelst [2] for the numerical approximation of the power of the tests. In this contribution, the precision of the Verhelst approach is investigated and compared with an exact sampling procedure proposed by Miller and Harrison [3] for which the discrete probability distribution to be sampled from is exactly known. Results show no substantial differences between the two numerical procedures and quite accurate power computations. Regarding the question of computing time the Verhelst approach will have to be considered much more efficient.

关键词： Conditional tests Conditional Probability Distribution Hypergeometric Distribution Power Function Random Sampling Rasch Model