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5.1 Since the beginning of human history, currency has existed in the form of metal coins and bullion. Thieves learned that shaving some precious metal provided a method to change its value. Substitution of common metals for precious metals of higher value was commonplace until weighing methods became so accurate, that it became easily detected. Alloys were also used as substitutes until inexpensive spectrometers became available which ended the counterfeiting practice. The rapid rise in the value of gold inspired the unscrupulous to find a new method. Tungsten was widely used for light bulb filaments until regulations changed that market. The great abundance of tungsten now available, coupled with the almost identical density of gold, presented a new opportunity.5.2 RUS provides a method to create an unique electronic signature for each piece tested which is operator independent.1.1 This practice is intended for use with resonant ultrasound spectrometers capable of exciting, measuring, recording, and analyzing multiple whole body mechanical vibration resonant frequencies within parts exhibiting acoustical ringing in the acoustic or ultrasonic, or both, resonant frequency ranges.1.2 This practice uses Resonant Ultrasound Spectroscopy (RUS) to distinguish conforming parts, as determined from qualified training sets, from those containing significant anomalies in their elastic properties.1.3 The basic functions of a RUS monitoring system are to detect and classify resonance phenomena. Solid structure resonances are governed by the part’s dimensions, density, and elastic properties. When a material substitution occurs in a precious metal, the chosen metals have almost identical densities and unchanged dimensions, leaving only the elastic properties to affect the resonances.1.4 This practice can be used to replace destructive methods, which damage the test object through drilling or melting, or both.1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.6 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.1.7 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 Constant drawdown test procedures are used with appropriate analytical procedures to determine transmissivity, hydraulic conductivity, and storage coefficient of aquifers.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors: Practice D3740 provides a means of evaluating some of those factors.1.1 This practice covers the methods for controlling drawdown and measuring discharge rates and head to analyze the hydraulic properties of an aquifer or aquifers.1.2 This practice is used in conjunction with analytical procedures such as those of Jacob and Lohman (1)/(2),2 and Hantush (3).1.3 The appropriate field and analytical procedures for determining hydraulic properties of aquifer systems are selected as described in Guide D4043.1.4 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 and health practices and determine the applicability of regulatory limitations prior to use.1.5 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

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5.1 The performance characteristics of a drainage geosynthetic are directly related to the integrity under compressive loading. If the product is sensitive to compressive deformation, its flow capacity could be greatly reduced or even shut off completely.5.2 The deformation sensitivity of a candidate geosynthetic can be tested at field-simulated normal stress and potential tangential stresses.5.3 This test method does not evaluate the effect of deformation of a geotextile filter or adjacent membrane.5.4 Compression deformation, as it relates to reduction in flow capacity of a geosynthetic drainage product, is manufacturer and product specific. For example, a 10 % reduction in original thickness of a geonet made by Manufacturer A does not necessarily equal the same reduction in flow capacity as a 10 % reduction in thickness of the same or another type of geonet made by Manufacturer B.5.5 This deformation data has merit directly to the end user, because it can be easily interpreted to result in a reduction factor for compressive deformation.4 The reduction factor can then be used to derive an allowable flow rate.51.1 This test method is used to determine the unconfined compressive deformation (consolidation) characteristics of drainage geotextiles, geocomposites, geonets, or any other geosynthetic associated with drainage at a constant temperature, when subjected to a constant compressive stress.1.2 This test method is intended for use as an unconfined compressive performance deformation test only. For a detailed procedure on how to establish an index test, see EN ISO 25619-1. For performance tests, the specimen shall be subjected to the site-specific liquid, the site-specific stress (normal and potentially a tangential stress on the upper and parallel loading platen), or both.NOTE 1: Results achieved from unconfined compressive performance deformation testing may differ from testing performed under confined conditions.1.3 Because of the changing nature of the geosynthetic industry and the wide variety of products already available, this particular test method may have to be slightly modified for unconfined compression deformation testing of some products.1.4 The values given in SI units are to be considered as the standard. The values given in parentheses are for information only.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.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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5.1 This test method for the determination of ball bursting strength of textiles is being used by the textile industry for the evaluation of a wide variety of fabrics.5.2 Test results obtained using the procedures in Test Method D3787 have not been correlated with actual performance. Test Method D3787 is considered satisfactory for acceptance testing of commercial shipments of textiles fabrics for bursting strength since the method has been used extensively in the trade for acceptance testing. In cases of disagreement arising from differences in values reported by the purchaser and the seller when using Test Method D3787 for acceptance testing, the statistical bias, if any, between the laboratory of the purchaser and the laboratory of the seller should be determined with comparison based on testing specimens randomly drawn from one sample of material of the type being evaluated.NOTE 3: The kind of force transfer and strength that occur when knitted goods are worn is prevented by clamping them as directed in this test method.5.2.1 If there are differences of practical significance between reported test results for two (or more) laboratories, comparative tests should be performed to determine if there is a statistical bias between them. The test samples used should be as homogeneous as possible, drawn from the material from which the disparate test results were obtained, and randomly assigned in equal numbers to the laboratories for testing. Other materials with established test values may be used for this purpose. The test results from the two laboratories should be compared using a statistical test for unpaired data at a probability level chosen prior to the testing series. If a bias is found, either the cause must be determined and corrected or future test results must be adjusted in consideration of known bias.1.1 This test method describes the measurement for bursting strength with a ball burst strength tester of textiles or garments that exhibit a high degree of ultimate elongation.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.NOTE 1: For the measurement of bursting strength with a hydraulic testing machine, refer to Test Method D3786.NOTE 2: Constant Rate of Traverse (CRT) machines and Constant Rate of Extension (CRE) machines have been shown to provide different results. When using a CRE device, refer to Test Method D6797.1.3 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.1.4 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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4.1 Dissipation Factor (or Power Factor)—This is a measure of the dielectric losses in an electrical insulating liquid when used in an alternating electric field and of the energy dissipated as heat. A low dissipation factor or power factor indicates low ac dielectric losses. Dissipation factor or power factor may be useful as a means of quality control, and as an indication of changes in quality resulting from contamination and deterioration in service or as a result of handling.4.1.1 The loss characteristic is commonly measured in terms of dissipation factor (tangent of the loss angle) or of power factor (sine of the loss angle) and may be expressed as a decimal value or as a percentage. For decimal values up to 0.05, dissipation factor and power factor values are equal to each other within about one part in one thousand. In general, since the dissipation factor or power factor of insulating oils in good condition have decimal values below 0.005, the two measurements (terms) may be considered interchangeable.4.1.2 The exact relationship between dissipation factor (D) and power factor (PF ) is given by the following equations:The reported value of D or PF may be expressed as a decimal value or as a percentage. For example:4.2 Relative Permittivity (Dielectric Constant)—Insulating liquids are used in general either to insulate components of an electrical network from each other and from ground, alone or in combination with solid insulating materials, or to function as the dielectric of a capacitor. For the first use, a low value of relative permittivity is often desirable in order to have the capacitance be as small as possible, consistent with acceptable chemical and heat transfer properties. However, an intermediate value of relative permittivity may sometimes be advantageous in achieving a better voltage distribution of ac electric fields between the liquid and solid insulating materials with which the liquid may be in series. When used as the dielectric in a capacitor, it is desirable to have a higher value of relative permittivity so the physical size of the capacitor may be as small as possible.4.3 Theory relating to dielectric measurement techniques and to sources of dielectric loss is given in Test Methods D150.1.1 This test method describes testing of new electrical insulating liquids as well as liquids in service or subsequent to service in cables, transformers, oil circuit breakers, and other electrical apparatus.1.2 This test method provides a procedure for making referee tests at a commercial frequency of between 45 Hz and 65 Hz.1.3 Where it is desired to make routine determinations requiring less accuracy, certain modifications to this test method are permitted as described in Sections 16 to 24.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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 to determine the applicability of regulatory limitations prior to use. Specific warnings are given in 11.3.3.1.6 Mercury has been designated by the EPA and many state agencies as a hazardous material that can cause nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for details and the EPA's website for additional information. Users should be aware that selling mercury and/or mercury containing products into your state may be prohibited by state law.1.7 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 practice allows the user to compute the true hydraulic efficiency of a pumped well in a confined aquifer from a constant rate pumping field test. The procedures described constitute the only valid method of determining well efficiency. Some practitioners have confused well efficiency with percentage of head loss associated with laminar flow, a parameter commonly determined from a step-drawdown test. Well efficiency, however, cannot be determined from a step-drawdown test but only can be determined from a constant rate test.5.2 Assumptions: 5.2.1 Control well discharges at a constant rate, Q.5.2.2 Control well is of infinitesimal diameter.5.2.3 Data are obtained from the control well and, if available, a number of observation wells.5.2.4 The aquifer is confined, homogeneous, and extensive. The aquifer may be anisotropic, and if so, the directions of maximum and minimum hydraulic conductivity are horizontal and vertical, respectively.5.2.5 Discharge from the well is derived exclusively from storage in the aquifer.5.3 Calculation Requirements—For the special case of partially penetrating wells, application of this practice may be computationally intensive. The function fs shown in Eq 6 should be evaluated using arbitrary input parameters. It is not practical to use existing, somewhat limited, tables of values for fs and, because this equation is rather formidable, it may not be tractable by hand. Because of this, it is assumed the practitioner using this practice will have available a computerized procedure for evaluating the function fs. This can be accomplished using commercially available mathematical software including some spreadsheet applications. If calculating fs is not practical, it is recommended to substitute the Kozeny equation for the Hantush equation as previously described.NOTE 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.NOTE 2: Commercially available software is available for the calculating, graphing, plotting, and analyses of this practice. The user is responsible for verifying the correctness of the formulas, graphs, plots and analyses of the software.1.1 This practice describes an analytical procedure for determining the hydraulic efficiency of a production well in a confined aquifer. It involves comparing the actual drawdown in the well to the theoretical minimum drawdown achievable and is based upon data and aquifer coefficients obtained from a constant rate pumping test.1.2 This analytical practice is used in conjunction with the field procedure, Test Method D4050.1.3 The values stated in inch-pound units are to be regarded as standard, except as noted below. The values given in parentheses are mathematical conversions to SI units, which are provided for information only and are not considered standard. The reporting of results in units other than inch-pound shall not be regarded as nonconformance with this standard.1.3.1 The gravitational system of inch-pound units is used when dealing with inch-pound units. In this system, the pound (lbf) represents a unit of force (weight), while the unit for mass is slugs.1.4 Limitations—The limitations of the technique for determination of well efficiency are related primarily to the correspondence between the field situation and the simplifying assumption of this practice.1.5 All observed and calculated values shall conform to the guidelines for significant digits and round established in Practice D6026, unless superseded by this standard.1.5.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported date to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis method for engineering design.1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without the consideration of a project’s many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.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.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 method is an indicator of the wear characteristics of petroleum hydraulic fluids operating in a constant volume vane pump. Excessive wear in vane pumps could lead to malfunction of hydraulic systems in critical industrial or mobile hydraulic applications.1.1 This test method covers a constant volume high-pressure vane pump test procedure for indicating the wear characteristics of petroleum hydraulic fluids. See Annex A1 for recommended testing conditions for water-based synthetic fluids.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 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.1.4 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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