Development Of Test Standards Research Articles

A NEW APPROACH TO TENSILE TESTING OF GFRP BARS

Tensile testing is a critical procedure for evaluating the mechanical properties of Glass Fiber Reinforced Polymer (GFRP) bars, which emerged as an alternative to traditional steel reinforcement in reinforced concrete structures. While significant research has led to the development of testing standards for GFRP bars, their implementation often necessitates additional specimens and specialized equipment compared to their steel counterparts. This study proposes a new method for conducting GFRP tensile tests using standard equipment designed for conventional structural steel rebar testing. By employing existing devices, our approach offers a practical and cost-effective solution for assessing the tensile properties of GFRP reinforcement. This simplified testing method aims to enhance efficiency, facilitate wider adoption of GFRP bars in reinforced concrete structures, and contribute to the advancement of sustainable construction practices.

RESEARCH ON FORMULATION OF HARD CAPSULES CONTAINING EXTRACTS OF HOUTTUYNIA CORDATA THUMB (SAURURACEAE), MORUS ALBA L. (MORACEAE), AND CARICA PAPAYA L. (CARICACEAE)

Background: previous studies have demonstrated that Houttuynia cordata Thumb (Saururaceae), Morus alba L. (Moraceae), and Carica papaya L. (Caricaceae) are effective against various viruses, especially the SARS-CoV-2 virus. In Vietnam, even though the three of these plant species are grown quite popularly and are pretty commonly consumed by residents regularly, there have not been any applications to the dosage forms to promote their full potential effects and make these dosage forms easy to use and preserve. Furthermore, no research has been conducted on a capsule form that combines all three of these medicinal herbs. Objectives: the research focuses on the composition of a hard capsule formula containing the extracts of Houttuynia cordata, Morus alba, and Carica papaya as well as the development of testing standards for prepared hard capsules. Materials and methods: the ratio of adsorbents and fillers in the formula was investigated so that the granules had low moisture, a suitable flow rate, and the appropriate apparent density for packaging; standards for testing capsules were developed according to current regulations. Results: the selected adsorbent was light MgCO3, with a ratio of plant extract: filler: adsorbent of 10: 5: 0.5 and a ratio of Avicel: Starch 1500 of 1: 3. Conclusions: a hard capsule containing medicinal plant extract was formulated with a moisture content of < 5% and well-flowing granules that had the suitable apparent density for packing the capsule size of 0. Capsules met standards in terms of appearance, weight uniformity, disintegration, heavy metal and microorganisms, with a quercetin content of 74.45 ± 0.23 mg. The result of the study is considered one of the most essential bases for further research on determining the effectiveness of medicines derived from medicinal plants and applied to support the treatment of COVID-19, which is still happening in a quite complicated way at the moment.

A spatial resolution evaluation method of endoscopic optical coherence tomography system using the annular phantom.

As an important biomedical imaging method, endoscopic optical coherence tomography (OCT) is necessary to check its performance regularly. The ordinary plane phantoms are only able to evaluate part of image tangent to the probe. In this research, a spatial resolution estimate method of the endoscope OCT system is proposed. The annular phantom, made by uniformly distributing golden scattered microparticles in polydimethylsiloxane (PDMS), can provide dynamic scanning imaging evaluation of endoscopic OCT system, closer to its actual working status. The point spread function analysis method is used to analyze the imaging results of the annular phantom with the endoscopic OCT system. And many scattered particles are statistically analyzed to determine the spatial resolution of the endoscope OCT system. The method is low in cost, simple and convenient. It is valuable for the development of test standards for endoscope OCT systems.

A Systematic Review of Reliability Issues in RF-MEMS Switches

The main challenge in the commercialization of the RF-MEMS switches is their reliability, related to both the electrical and mechanical domains. The development of test standards and understanding the underlying physics of different failure modes has always been of major concern for the RF-MEMS designers. This paper reviews the different failure modes in the RF-MEMS switches like stiction, residual stress, cyclic fatigue, creep, wear and packaging in detail. The origin of these failure modes, their characterization procedure and respective solutions presented in the literature are presented to get a better understanding of the state of the art work done in the field RF-MEMS reliability for nearly past two decades.

Non-invasive foetal RhD genotyping to guide anti-D prophylaxis: an external quality assurance workshop.

Alloimmunisation against the D antigen in pregnant RhD-negative women is preventable using anti-D immune prophylaxis1. A combination of antenatal and postnatal anti-D administration has dramatically reduced alloimmunisation of RhD negative women from 16% to 0.3%1,2. Analysis of cell-free foetal DNA (cffDNA) circulating in maternal plasma facilitates non-invasive antenatal testing of the foetal RhD genotype at an early gestational age3,4. Knowledge of the foetal RhD type allows targeted use of antenatal prophylaxis, avoiding unnecessary treatment of RhD-negative women who are carrying a RhD-negative foetus, and are thus at no risk of immunisation5. Routine foetal RhD genotyping using cffDNA has been introduced as a national service in Denmark, the Netherlands, and Finland, with several other countries also offering the service regionally6,7. Some countries are in the process of national implementation, while others await approval from their national health authorities. As a consequence of the high performance of non-invasive foetal RhD genotyping, cord blood typing has been discontinued in Denmark and the Netherlands1,8. Without confirmatory testing of the neonate’s RhD type, non-invasive foetal RhD genotyping can no longer be verified, and quality control of the assay becomes increasingly important. Additionally, many laboratories require annual external testing as part of their quality control programme. Here, we report the results from an external quality assurance workshop, EQA 2016, in which 22 laboratories participated in testing two plasma samples from pregnant RhD-negative women, with the aim of future development of standards for testing for foetal RhD genotype.

Characterization of Strength and Durability of Ultra-High-Performance Concrete under Variable Curing Conditions

One of the latest advancements in concrete technology is ultra-high-performance concrete (UHPC), a fiber-reinforced, densely packed material that exhibits increased mechanical performance and superior durability compared with normal- and high-strength concretes. UHPC has great potential to be used in the bridge market in the United States. However, to gain acceptance by designers, contractors, precasters, and owners, this material needs to be tested according to ASTM International and AASHTO standards, and new practices must be developed. The variability in performance that is based on new challenges of mixing and curing must also be considered. The effects of curing regimes and specimen age on the strength and durability properties of a fiber-reinforced UHPC was investigated. Regardless of when the thermal treatment was applied, UHPC consistently attained compressive stresses above 30 ksi (207 MPa), a modulus of elasticity of approximately 8,000 ksi (55 GPa), and a Poisson's ratio of 0.21. Flexural characteristics were enhanced with high-temperature curing. UHPC also demonstrated extremely high resistance to freeze–thaw cycling (with a durability factor of more than 100), coefficient of thermal expansion values only slightly higher than that of normal-strength concrete, and negligible chloride ion penetration. Furthermore, modified versions of ASTM and AASHTO standard testing methods were employed to aid in development of draft standards for testing some UHPC material properties in the United States that will eventually lead to a national design code.

Minimum requirements for new dental materials*

A brief review of the development of standards for testing and certification of dental materials is presented. The tests employed in the standards are not correlated for the clinical use of the materials, nor to the reasons for failures of the materials. They are, therefore, of limited value for the selection of materials to be used in practice but they are important for quality control of the manufacture of the materials. Previous certification programmes are being discontinued. The responsibility for selecting safe and efficient materials is transferred to the clinicians whereas making safe and efficient materials still is the responsibility of the manufacturers.

Real HBM and MM waveform parameters

Recent “real” human body model and machine model discharge waveform measurements provide completely new data on the risetime and peak current threats to devices. Additional investigations were performed to determine the impact of humidity and electric field effects on the discharge event. Given the new information, redesign of ESD simulators and development of test standards representing real-world ESD threats are essential.

Development of test standards for continuous fiber ceramic composites in the United States

Standardization activities in the United States for continuous fiber-reinforced ceramic composites (CFCCs) are reviewed. This brief review focuses on the development of test standards by subcommittee C28.07 of the American Society for Testing and Materials (ASTM) on the drafting of a section of a design code for ceramic and ceramic matrix composite components as part of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, and on the development of a set of volumes on ceramic matrix composites for Military Handbook 17 on composites. The participation of the US in the international harmonization of standards for CFCCs is also reviewed.

Research in Protective Clothing for Firefighters: State of the Art and Future Directions

This paper presents a summary of documented research into protective clothing for firefighters. Particular emphasis is placed on research into estimating the useful life of this clothing and the development of test standards for evaluating its thermal protection. Other areas covered in this review include moisture transfer in clothing, heat stress, design criteria, chemical protective clothing, and heat transfer modeling of protective clothing. Recommendations for future protective clothing research are also presented.

The 'pproaches to 'tudy ☆nventory in Malawi: a lesson for educational testing?

It is important to identify the best fit between the learning environment and students’ preferred modes of learning, and we aimed to explore the utility of the Approaches to Study Inventory (ASI) in Malawi, which has one of the poorest resourced educational systems on the African continent. Two hundred and fourteen undergraduates from a variety of faculties of the University of Malawi completed the short (18 item) form of the ASI. Factor analysis suggested both etic and emic orientations to study, from Reproducing and Organized study behaviour to Achievement-in-Context (which may entail a traditional sense of meaning). This search for a practical instrument to improve the match between teaching product and student study style suggests that such devices may often need to be developed locally. We discuss the implications of our results for the ongoing development of testing standards by the International Test Commission.

Promoting High Standards for Test Use: Developments in the United States

Recent developments in the United States regarding the promotion of high standards for test use are described. Four areas are covered: the development of testing standards, qualifications to purchase and use tests, educating test users, and developments to watch (computer-based testing and performance testing). It is argued that at the same time as we are opening the way to improved testing through innovative applications of computer technology and performance assessments, there are economic forces that have the potential to undermine our basic standards. Each of the professionals in the field of testing must contribute their talent to upholding high standards to that test takers derive the benefits that come from the productive use of tests.