Review and Comparison of Methods for Vibration Qualification Testing

Comparison of standard test methods for non-lubricated sliding wear

In this work, the design qualification testing, evaluation and test methods of gas generator using double base (DB) propellant having square flake shape is explained for an improvised explosive devices (IEDs) applications. Various kinds of the gas generators are used to save life of an aeronaut in the fastest way from the disable fighter aircraft. Due to their ruggedised design, compactness, safe transportation, repeatability in performance and quick operation, the gas generator are used. The gas generator is designed and developed keeping functional, mechanical and structural requirements in mind. The gas generators are subjected to the various qualification tests, electrical characterisation followed by closed vessel (CV) firings at hot and cold temperatures. The gas generators after the successful qualification tests are validated through the ground trials i.e. dynamic firing of disruptor during the development phase. The damage caused due to impact of the projectile is assessed in terms of crater as acceptance criteria at stand-off distance of 0.5 m and 1m. The gas generator discussed in this research article is used to disrupt the suspected IEDs by creating a high-speed jet using water-jet disruptor. In conclusion, after successful qualification testing, the gas generator for IEDs application meets all the specifications as per user’s requirements.

Evaluation of the Dairy Herd Improvement Association Record System

Introduction: The emergence of resistance to colistin urges the need for standardised invitro susceptibility testing methods for colistin, both for patient care and also for epidemiological purpose. Many challenges have been faced by clinical laboratories in performing and interpreting Antimicrobial Susceptibility Testing (AST) methods for colistin. To overcome the challenges, a rapid and reliable method is required to carry out AST for colistin. Aim: To determine the degree of agreement and types of errors associated with various colistin antimicrobial susceptibility methods such as commercial Broth Microdilution (BMD) method (MIKROLATEST- Erba Mannheim colistin MIC kit) and in-house Rapid polymyxin NP test (named after P. Nordmann and L. Poirel) with the reference in-house BMD method. Materials and Methods: The study was carried out in a tertiary care hospital in southern India from July 2018 to July 2019. The isolates from Enterobacteriaceae family showing resistance to carbapenem were selected for the study. A total of 294 clinical isolates were collected and subjected to two test methods (Commercial BMD method and Rapid polymyxin NP test) and finally the comparative analytical study was done by comparing the results of the test methods with reference in-house BMD method. The statistical analysis was carried out with the help of Stata version 14 using kappa statistics. Results: Susceptibility results of 294 isolates included Escherichia coli (n=67), K.pneumoniae (n=195), Enterobacter spp. (n=23), Citrobacter spp. (n=9) were evaluated for three methods according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) published clinical breakpoints. Overall, categorical agreement of commercial BMD with reference in-house method was 91.1% with very major error 2.7% and major error 6.1% and essential agreement was 83.3%. With the Rapid polymyxin NP test, categorical agreement, sensitivity and specificity were 92.5%, 93.1% and 92.3% respectively. Conclusion: This study helps in introducing less laborious, faster and reliable susceptibility method for colistin. This will guide the clinicians in appropriate and judicious use of colistin so that mortality and morbidity will be reduced drastically.

A comparison of test methods to assess the strength potential of plain and blended supplementary cementitious materials

Specific scopeThis standard describes the production of certified pathogen‐tested material ofRubus.Specific approval and amendmentFirst approved in 2004–09.Revised in 2009–09.

Setting time and rheology of mixtures are among the most important features in new generation concretes such as self-consolidating concrete (SCC) and can have a great impact on the behavior of fresh concrete. Therefore, introducing new methods for determining these parameters has always been one of the main concerns. In this research, we tried to determine a relationship between the measured setting time from the ASTM C403/C403M-08, Standard Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance Method, and the electrical resistance (ER) method, as well as the rheological parameters, including dynamic and static yield stress. Also, a new method for determining the setting time and concrete thixotropy—called the plate test method—is introduced and validated. The results indicated that the ER method is an accurate one in determining the initial and final setting time of SCC mixtures. Concrete mixtures with higher yield stress (static and dynamic) have a shorter setting time. Investigating the results indicated that the higher the static yield stress mean of the mixture in the time period of thixotropic behavior, the shorter the initial setting time. Therefore, increasing static yield stress is associated with a reduction in the setting time. In the case of dynamic yield stress, similar events occurred with static yield stresses, and an increase in this stress and its growth rate was associated with a reduction in the initial setting time. Furthermore, the results obtained by the new method (plate method), along with the results of rheology parameters measured by the rheometer device, indicated that the difference between results was in the range of 4 to 11 %. Also, the difference in the setting time obtained from the plate method in comparison with the penetration resistance method was 9 % at maximum. These results indicated that the plate test method has an acceptable accuracy in measuring the setting time and thixotropy.

The results of a statistical evaluation of ten impact test methods are presented in this paper. The concept of “good impact test” has two aspects: the quality and the applicability of the test results. The applicability of various test methods for predicting in-service performance is the subject of a companion paper. This paper presents an evaluation of the quality of the test output, as well as an analysis of the correlation between various test outputs. The ten test methods evaluated—three pendulum, one tensile, four drop dart, one flex, and one driven dart—are described briefly. Three of the test instruments were instrumented. Seven materials, ranging from unfilled thermoplastics to reinforced thermosets, were tested by each of the methods. Evaluation of a test's output quality is developed in terms of the range of applicability and the degree of material differentiation. Specific factors that serve as criteria include the existence and distinctness of failure, and the spread and scatter of measured results. The test methods are ranked from “highly desirable” to “severely restricted.” Evaluation of the correlation of material ranking by the various test methods is presented. In general, results from different impact tests do not correlate. However, there are instances of strong or fair correlation. The degree of correlation is explained in relation to the similarity of test stress states and measured characteristics. It is meaningful to classify impact tests according to stress states and measured characteristics. Material selection for impact performance should be based on test methods that simulate the stress states, controlling variables, and failure limits of the intended application.

As the size of software is getting huge, it is difficult for testers to check out all parts of source code in white-box style during integration testing or system testing period. Therefore functional test methods based on requirements information are frequently used in system level test. There have been a lot of test methods based on requirement specification. Each method has a different approach to specify software requirements. Test engineer should consider those various aspects of approaches and select proper black-box testing method to be applied. This paper presents the empirical comparison of major black-box testing methods and shows the different results by applying them to test a certain software system. The result shows that blackbox testing methods check different levels of code construct. Test planer should consider the combination for the efficient test methods which combine extended use case test method and OCL test method.

Several test methods exist for determining the water vapour permeability or resistance of textile fabrics or garments. The differences and interrelationships between these methods are not always clear, which presents a problem in comparing results from different test methods. This study is aimed at investigating the relationships between the test results from four typical test methods, including the moisture transmission test (Model CS-141), ASTM E96 cup method, sweating guarded hot plate method (ISO11092) and the sweating fabric manikin (Walter). For the range of air permeable knitted fabrics tested, it was found that good interrelationships exist between the results from the four types of test methods, although some discrepancies exist between different tests due to differences in testing conditions. Test results from different moisture transfer test methods can therefore be convertible with due consideration.

Comparison of test methods for evaluation of thermal performance of preheat and solar-only factory made systems

: The vibration qualification test described within this report completes the vibration qualification requirements as established by the LDEF Project Office for flight hardware association with the SD802 materials experiment. The combined environment temperature altitude test described was completed to establish the operating stability of electronic components within the signal conditioning electronic units (SCUs). (Author)

: The Joint Oil Analysis Program previously revised the specification for their spectrometric oil standards in order to incorporate an ICP-AES test method and to transition to commercially manufactured spectrometric oil standards. Historically, a Rotrode-AES test method was the only elemental test method used to verify the quality of the spectrometric oil standards. The Rotrode-AES test method was a labor and time intensive process that did not exhibit a high level of accuracy and repeatability. The JOAP wanted to incorporate an ICP-AES test method in order to obtain a more accurate determination of the true concentration of the elements in the spectrometric oil standards and to reduce the cost and time needed to conduct quality assurance. Both the Rotrode-AES and ICP-AES test methods are now part of the qualification inspection in order to ensure that commercially manufactured spectrometric oil standards are identical to those that have been produced in-house by the JOAP. This report covers the qualification testing of Type D19-0, Type D12-XXX series, and Type D3-100, candidate spectrometric oil standards submitted by SCP Science (Conostan) against the requirements of MIL-DTL-85694. In general, the candidate spectrometric oil standards met the requirements of the specification. A few specific data points were analyzed and waived based on alternative testing and analysis. As a result of this testing and analysis effort the SCP Science (Conostan) Type D19-0, Type D12-XXX series, and Type D3-100 spectrometric oil standards have been qualified to the specification. Since this qualification testing effort was only the second time the full range of data required by MIL-DTL-85694 has been collected, analysis of the data has led to the conclusion that several of the requirements of the specification need revision. Several changes to the specification are therefore under consideration based on historical knowledge of JOAP manufactured spectrometric oil standards and the MIL

Introduction. In the world-wide practice on construction of rigid road pavements significant attention has been given to jointed plain concrete pavements (JPCP) with transverse joints strengthened by dowel bars. Performance of JPCP is sufficiently affected by right alignment and location of dowel bars thereby the methods of non-destructive testing of dowel bar positioning have been gain in great importance. This paper represents analytical review of methods of non-destructive testing of dowel bar alignment and location emphasizing an attention on standard method using magnetic pulse induction which is applicable to testing of metallic bar position in concrete pavements. General Part. In the general part of this paper, several main aspects of reviewed test method were analyzed: the classification of dowel bars misalignment and their impact on pavement performance; the comparison of implemented methods of non-destructive testing of dowel bar positioning; possibilities of method of magnetic impulse induction and an approach to analytical evaluation of transverse joints dowel bar misalignment using magnetic image tomography; the usage of results of testing of transverse joints dowel bar position to eliminate dowel bars misalignment; examples of predictive estimation of results of testing of transverse joints dowel bar position and their impact on performance of JPCP. The reviewed method of testing and test results estimation concerns practice on application of two levels of performance (e.g. acceptable level and rejectable level) to evaluate the performance of each individual dowel bar or each doweled transverse joint and also a section of rigid road pavement with several consecutive transverse joints with restricted performance. Conclusions. 1. World-wide implemented standard method of non-destructive testing of dowel bar alignment and location allows to detect and to eliminate dowel bars misalignment thus ensuring required load transfer efficiency and international roughness index of rigid road pavements. The estimation of road pavement sections with several consecutive joints considering each joint performance allows to ensure the designed service life of road pavement. 2. Standard method of non-destructive testing of dowel bar alignment and location for transverse joints of rigid road pavement using magnetic pulse induction developed by American Society for Testing and Materials assures high precision of measurement of metallic bar position in doweled bar of concrete pavement joints and enables to detect five types of dowel bar misalignment. 3. In connection with the intensification of issues on construction of rigid road pavements in Ukraine as well as the high importance of the considering test method, an important task should be the development and implementation of an appropriate national standard.

Development and comparison of the test methods proposed in the Chinese test specifications for fuel cell electric vehicles