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4.1 Products are exposed to complex dynamic stresses in the transportation environment. The determination of the resonant frequencies of the product may aid the packaging designer in determining the proper packaging system to provide adequate protection for the product, as well as providing an understanding of the complex interactions between the components of the product as they relate to expected transportation vibration inputs.1.1 These test methods cover the determination of resonances of unpackaged products and components of unpackaged products by means of vertical linear motion at the surface on which the product is mounted for test. Two alternate test methods are presented:Test Method A—Resonance Search Using Sinusoidal Vibration, andTest Method B—Resonance Search Using Random Vibration.NOTE 1: The two test methods are not necessarily equivalent and may not produce the same results. It is possible that tests using random vibration may be more representative of the transport environment and may be conducted more quickly than sine tests.1.2 This information may be used to examine the response of products to vibration for product design purposes, or for the design of a container or interior package that will minimize transportation vibration inputs at these critical frequencies, when these products resonances are within the expected transportation environment frequency range. Since vibration damage is most likely to occur at product resonant frequencies, these resonances may be thought of as potential product fragility points.1.3 Information obtained from the optional dwell test methods may be used to assess the fatigue characteristics of the resonating components and for product modification. This may become necessary if the response of a product would require design of an impractical or excessively costly shipping container.1.4 These test methods do not necessarily simulate the vibration effects that the product will encounter in its operational or in-use environment. Other, more suitable test procedures should be used for this purpose.1.5 Test levels given in these test methods represent the correlation of the best information currently available from research investigation and from experience in the use of these test methods. If more applicable or accurate data are available, they should be substituted.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See Section 6 for specific precautionary statements.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test procedure provides a method of evaluating the frictional torque and friction factor of artificial hip joint bearings under the stated in-vitro test conditions.5.2 Friction is not simply a materials property. The specimen system and the effects on its friction are multi-factorial, including the materials and processing of the components, the design and assembly of the components, the test parameters, and environmental factors (lubricant, temperature, etc.).5.3 The procedure may be used as a standardized method of measuring friction for a particular system, or as a method of investigating the effects of specific test parameters such as hip sizes, designs, radial clearance, different lubricants, clamping (nonuniform sphericity), misalignments during installation, etc.5.4 The procedure may be used to study the variation of friction with time as the specimens wear, which is particularly useful for samples that undergo a transition from “run-in” to “steady-state” wear behavior. Since the motion and load waveforms are identical to those specified in ISO 14242-1:2014, standardized friction and wear measurements may be combined and viewed in the correct perspective where they affect each other.5.5 Frictional torque, and in particular the maximum value, are useful to assess the torques that may compromise fixation, or cause disassociation of modular components in acetabular cup or liner/shell assemblies through a lever-out or torsion-out mechanism.5.6 Friction factor is a useful parameter for comparison of materials and designs, and provides insights into the lubrication regime operating in the implant system. Friction factor measurement may also be able to detect acetabular liner deformation (clamping referred to earlier).1.1 This test procedure provides a method of evaluating the frictional torque and friction factor of artificial hip joint bearings used in Total Hip Replacement systems. The method presented here was based on a published study, first as a conference paper in 2008 (1)2 and then as a peer-reviewed journal paper (2). The method is compatible with and is capable of being carried out during actual wear testing of total hip replacement implants on wear simulators equipped with multiple degrees of freedom force and moment sensors.1.2 Although the methodology described does not replicate all physiological loading conditions, it is a means of in-vitro comparison of the frictional torque and friction factor of artificial hip joint bearings used in Total Hip Replacement systems under the stated test conditions.1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM D4411-03(2019) Standard Guide for Sampling Fluvial Sediment in Motion Active 发布日期 :  1970-01-01 实施日期 : 

4.1 This guide is general and is intended as a planning guide. To satisfactorily sample a specific site, an investigator must sometimes design new sampling equipment or modify existing equipment. Because of the dynamic nature of the transport process, the extent to which characteristics such as mass concentration and particle-size distribution are accurately represented in samples depends upon the method of collection. Sediment discharge is highly variable both in time and space so numerous samples properly collected with correctly designed equipment are necessary to provide data for discharge calculations. General properties of both temporal and spatial variations are discussed.1.1 This guide covers the equipment and basic procedures for sampling to determine discharge of sediment transported by moving liquids. Equipment and procedures were originally developed to sample mineral sediments transported by rivers but they are applicable to sampling a variety of sediments transported in open channels or closed conduits. Procedures do not apply to sediments transported by flotation.1.2 This guide does not pertain directly to sampling to determine nondischarge-weighted concentrations, which in special instances are of interest. However, much of the descriptive information on sampler requirements and sediment transport phenomena is applicable in sampling for these concentrations, and 9.2.8 and 13.1.3 briefly specify suitable equipment. Additional information on this subject will be added in the future.1.3 The cited references are not compiled as standards; however they do contain information that helps ensure standard design of equipment and procedures.1.4 Information given in this guide on sampling to determine bedload discharge is solely descriptive because no specific sampling equipment or procedures are presently accepted as representative of the state-of-the-art. As this situation changes, details will be added to this guide.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 12.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1. Scope 1.1 This Standard describes the investigations required to obtain the seismological and geological information necessary to determine, for a proposed CANDU nuclear power plant site, the seismic ground motion that will be utilized in seismic qu

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AS 1115-1985 Numerical control of machines - Axis and motion nomenclature 被代替 发布日期 :  1970-01-01 实施日期 : 

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1. Scope 1.1 This Standard applies to design and performance criteria of operator controls located at the normal operating position. 1.2 This Standard provides guidelines for operator controls as relating to uniformity of location and direction of

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