A Segmented Cylinder Test for Determining Hoop Stress in Composite Structures

One of the key new features of connected lighting systems (CLS) is their ability to collect data from various types of integral sensors and share that data with other lighting or building systems. Occupancy and vacancy sensors have been widely adopted as an energy-saving strategy in buildings, yet published test methods for reproducibly characterizing their performance remain few and limited in their sophistication. As a result, it has been difficult to predict the performance of such sensors in a specific application, and in practice, they frequently do not meet energy-savings expectations. Occupants at times remove or otherwise bypass occupancy sensors that hinder their work or otherwise do not perform as expected, thereby compromising the sensors’ potential to reduce energy consumption. Poor performance can result from multiple causes – ranging from fundamental limitations of the sensor technology, to misconfiguration, to poor placement in the room or space. Innovative occupancy sensors, some of them combining multiple sensing technologies (i.e., multimodal), have come on the market over the years, with claims of improved performance compared to their predecessors. However, in practice, their performance has neither differed enough from the performance of previous products to necessitate a test method that facilitated comparison between them, nor has it led to high deployment or high user satisfaction in human-occupied spaces with persistent presence. While the performance of both common and novel occupancy sensors has been the subject of many published research articles, the test methods that have been employed for them typically have been loosely described and have incorporated custom equipment or techniques that render them difficult to reproduce, or have been limited in their ability to fairly characterize devices that utilize varying sensor technology. The lack of a fully described, technology-agnostic test method that yields reproducible results across different implementations has been a barrier to the commercial success of new occupancy-sensor products, as users and specifiers who have been disappointed with previous products are often unwilling to take a chance with new ones. Motivated by a desire to fairly characterize new technologies that continue to enter the market and claim not only improved occupancy detection but, in some cases, additional capabilities (e.g., the ability to measure traffic or discern between different object types), this report presents the results of a literature review of recently published fully described test methods for characterizing occupancy-sensor performance, as well as research articles containing ad-hoc test methods. The review also identifies and consolidates test conditions for characterizing sensor performance in indoor spaces and identifies apparent test method gaps that need to be filled in order to evaluate emerging technologies and products. The identified test-method conditions are intended to enable the development of a future technology-agnostic test method that facilitates occupancy-sensor performance characterization more-accurately representing performance in buildings.

INVESTIGATION OF INOSINE AND HYPOXANTHINE AS BIOMARKERS OF CARDIAC ISCHEMIA IN PLASMA OF NON-TRAUMATIC CHEST PAIN PATIENTS AND A RAPID ANALYTICAL SYSTEM FOR ASSESSMENT By Don E. Farthing, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2008 Major Director: H. THOMAS KARNES, Ph.D. PROFESSOR, DEPARTMENT OF PHARMACEUTICS Each year in the U.S., approximately 7-8 million patients with non-traumatic chest pain visit hospital emergency departments (ED) for medical evaluation. It is estimated that approximately 2-5% of these patients are experiencing acute cardiac ischemia, but due to the shortcomings of current test methods, they are incorrectly diagnosed and discharged without appropriate treatment provided, thus leading to poor patient outcome and potential medical malpractice litigation. The goals of this research were to evaluate plasma samples xxvi for potential biomarker(s) of acute cardiac ischemia prior to heart tissue necrosis, and to ultimately develop a rapid method for detection of the potential biomarker(s) in human plasma. Initial experiments were performed using the mouse model, with subsequent evaluations on human plasma samples using high performance liquid chromatographic ultraviolet detection (HPLC-UV). The final phase of this research involved the development of a rapid luminometer test method (<10 min analysis time objective) to be potentially used in the clinical laboratory environment. An HPLC-UV detection method was developed and utilized for inosine, hypoxanthine and other adenosine triphosphate (ATP) catabolic by-products in KrebsHenseleit (Krebs) buffer solution, with analysis on perfusate samples from isolated mouse hearts undergoing 20 min acute global ischemia. The HPLC-UV method was modified for subsequent use on human plasma samples, obtained from hospital emergency department (ED) patients presenting with non-traumatic chest pain (potential acute cardiac ischemia) and from healthy normal individuals. The HPLC-UV (component quantification) and HPLC-MS (component identification) test methods utilized C18 column technology, mobile phases consisting of aqueous trifluoroacetic acid (0.05% TFA in deionized water pH 2.2, v/v) and methanol gradient to achieve component separation, with both utilizing simple sample preparations (e.g. direct injection of Krebs perfusate samples and centrifugal membrane filtration on plasma samples). Results of the animal experiments using isolated mouse hearts undergoing 20 min acute global ischemia demonstrated significant levels of endogenous inosine effluxed from the heart tissue, indicating its use as a potential candidate biomarker of acute cardiac xxvii ischemia. The HPLC results from human plasma representing ED non-traumatic chest pain patients demonstrated elevated levels of inosine (hypoxanthine precursor) and significant levels of hypoxanthine, which provided additional support for the use of these candidate biomarker(s) as a potential diagnostic tool for the initial acute cardiac ischemic event, prior to heart tissue necrosis. The final phase of this research focused on the development of a rapid, simple and sensitive chemiluminescence test method. Using a microplate luminometer with direct injectors and continuous mixing, the measurement of inosine and hypoxanthine in human plasma was achieved for healthy normal individuals and on patients with confirmed acute MI, with an analysis time of less than 5 minutes. The utility of this rapid luminescence technique would be the potential use at point-of-care (POC) services (e.g. hospital clinical laboratory or emergency medical services) as part of the initial ED treatment protocol on patients presenting with non-traumatic chest pain and signs/symptoms of acute myocardial ischemia or acute MI.

Nondestructive Testing (NDT) methods provide scientists a way to understand the properties of samples without causing them damage. For an electrochemical device, it is crucial to investigate the behavior of it before, during, and after its operation. Therefore, NDT methods are indispensable for studying such devices.Literature highlights the effectiveness of elastic-wave-based testing methods in the evaluation of electrochemical devices. The Acoustic Emission (AE) method was applied to respectively study the behavior of Solid Oxide Fuel Cells (SOFCs) and Ni-MH batteries, while the Ultrasonic Testing (UT) method was applied to study Li-ion batteries. In our previous research, the signals representing cracking and delamination in SOFCs were successfully distinguished by their peak amplitude, wave shape, and AE energy [1]. The same technique was further used for the evaluation of mechanical damages in SOFCs during the operation [2]. In another study, similarly, the pulverization of the Ni-MH battery electrodes was observed by the AE technique, and frequency peak property was included in the discussion to classify the signals [3]. The UT method was employed to study the relationship between the state of charge of Li-ion batteries and the profiles of ultrasonic waves at different frequencies. The evolution of wave velocity, attenuation, and amplitude were discussed [4]. Based on these researches, elastic-wave-based testing methods are adopted by us.In our present study, the multi-frequencies in-situ ultrasonic monitoring technique was employed to analyze the behavior of the commercial Ni-MH batteries during the operation. Continuous ultrasonic waves at three different frequencies were separately sent into the specimens during charge cycles, and their waveforms were recorded and compared. Specific wave patterns were found near the end of the charge and discharge state, especially from the wave profiles at 750 KHz. The result showed that the evolution of waveform is frequency-dependent, which was also suggested in the literature [4]. Potential explanations for these wave patterns were inferred, including phenomena such as crystal structure evolution, internal pressure shift, and reverse of electrodes.Based on this finding, a new ultrasonic testing/monitoring method considering frequency analysis is also designed. In this new method, signals consisting of elastic waves at a wide range of frequencies with equal intensities are designed to be applied to various electrochemical devices. The application of this method will be included, while the frequency-dependent property of the testing of electrochemical devices will be assessed in combination with the present findings in this study.

The use of moiré interferometry as an aid to standard test-method development for textile composite materials

The characterization method of aging properties is of great significance for the study of aging degree of polymer materials, including the rule and mechanism of aging, as well as the influence of environmental factors on aging. The research of these methods plays an important role in the development of new experimental technology and testing methods, the improvement of material production technology, the development of special materials, and the design of new materials according to specified properties. Among them, the characterization method of aging performance is mainly realized by mechanical property analysis. The changes of mechanical properties of polymer materials during aging mainly include the changes of impact strength and bending strength of plastics. Through the study of the mechanical property test method after the artificial accelerated aging of the non-metallic low-voltage metering box shell material, the corresponding technology and standards are provided for the quality control of the equipment in the field of smart grid measurement.

The idea of generalized stress increment testing method which contains both the stress free method and the stress superimposing method for the residual stress determination is developed. The research development of full and partial stress free testing methods is reviewed. Different testing methods are characterized according to the different working conditions. The stress superimposing testing method of residual stress is different from the stress free one. A new stress field is introduced adding on the initial state. The residual stress is indentified by the strain increment differences of the material detected in the stress superimposing process. The traditional stress superimposing testing method including hardness and indentation method are reviewed. The principal and application of two new type of stress superimposing testing methods of residual stress are introduced, their disadvantages are also indicated.

The most prevalent liver disease in humans is non-alcoholic fatty liver disease, characterised by excessive hepatic fat accumulation, or steatosis. The western diet and a sedentary lifestyle are considered to be major influences, but chemical exposure may also play a role. Suspected environmental chemicals of concern include pesticides, plasticizers, metals, and perfluorinated compounds. Here we present a detailed literature analysis of chemicals that may (or may not) be implicated in lipid accumulation in the liver, to provide a basis for developing and optimizing human steatosis-relevant in vitro test methods. Independently collated and reviewed reference and proficiency chemicals are needed to assist in the test method development where an assay is intended to ultimately be taken forward for OECD Test Guideline development purposes. The selection criteria and considerations required for acceptance of proficiency chemical selection for OECD Test Guideline development. (i.e., structural diversity, range of activity including negatives, relevant chemical sectors, global restrictions, etc.) is described herein. Of 160 chemicals initially screened for inclusion, 36 were prioritized for detailed review. Based on the selection criteria and a weight-of-evidence basis, 18 chemicals (9 steatosis inducers, 9 negatives), including some environmental chemicals of concern, were ranked as high priority chemicals to assist in vitro human steatosis test method optimisation and proficiency testing, and inform potential subsequent test method (pre-)validation.

Effective conventional manufacturing techniques are required to integrate the nanomaterial configurations into material systems at a larger component and structural level to obtain the enhanced benefits offered by the material configurations at the nano length scale. A low cost manufacturing process based on vacuum assisted resin transfer molding (VARTM) is demonstrated for the effective processing of fiber composite laminates using modified epoxy resin systems dispersed with nano and sub-micron alumina oxide particles. The effect of alumina oxide particles on the thermo physical properties (glass transition temperature, etc), are studied via differential scanning calorimetry and thermal gravimetric analysis. Higher glass transition temperatures with the alumina oxide and other nano particulate systems provide an opportunity to use conventional resin systems in high temperature applications. Ultrasonic mixing is employed to uniformly disperse the particles into an epoxy resin system. The flow characteristics of the modified resin system are not significantly different than the neat resin system and allowed the use of traditional VARTM processes successfully. The details of the resin modification and current studies on particulate modification for better interfacial bond are discussed in this paper. Wear performance for reinforced plastics are also investigated in this paper. Composite laminates with S2 glass and modified resins are fabricated. The mechanical behavior of the fabricated composite laminates with the neat and modified resin system using different sized and loading of alumina oxide particles are presented and discussed.

As the rodeo sport of bull-riding increases in popularity, dangers to bull-rider athlete safety continue to pose serious health risks. Despite frequent occurrences of head trauma in the sport, current test methods for evaluating helmets commonly worn in bull-riding fail to consider rotational head acceleration, which is correlated to concussive events in impact sports. Additionally, the second most prevalent mechanism contributing to head trauma in bull-riding is bull kick impacts, which have yet to be accurately modeled in a test method. Researchers aim to enhance bull-rider athlete protection through the development of a helmet test method that simulates bull kicks with a pneumatic linear impactor. The proposed test method considers impacts at two impact velocities and six impact locations using a flat and Equestrian Hazard Anvil. Two commonly worn helmets in bull-riding are evaluated in this study, and an adequate sample size is determined from analyzing variation between repeated impacts. The proposed test method is statistically validated, and researchers show that impacts at higher kicking velocities and impacts with the flat anvil result in increased rotational head accelerations. Ultimately, this study emphasizes the need for helmets designed specifically for the unique impacts of bull-riding by simulating bull kicks through pneumatic linear impactor testing to reduce rotational head kinematics and hoof penetration.

In this paper,several aspheric testing methods for different fabrication steps and their new research progresses are introduced. Especially,we emphasis on the testing methods for precision polishing step,in which subaperture stitching interferometric testing and non-null partial compensating testing method are described in detail. Moreover,several combined interferometric testing methods which perform well in measuring large and steep aspherics are introduced. In addition,we provide a general description of free-form surface testing. The further development of aspheric surface testing methods is also prospected.

Assessment of mechanical properties in unirradiated and irradiated zircaloys and steels with non-standard tests and finite element calculations

BackgroundExtensive drug resistance (XDR) is an emerging concern with Mannheimia haemolytica, and a variety of testing methods are available for characterizing in vitro antimicrobial susceptibility.ObjectivesTo compare the concordance among disk diffusion, broth microdilution, and whole genome sequencing (WGS) for susceptibility testing of M. haemolytica before and after mass treatment using tulathromycin.AnimalsForty‐eight M. haemolytica isolates collected from high‐risk beef stocker calves before and after mass treatment (metaphylaxis) using tulathromycin (Draxxin, Zoetis, Parsippany, NJ) given at the label dosage of 2.5 mg/kg body weight SC in the neck.MethodsIn vitro antimicrobial susceptibility was determined for all 48 isolates using disk diffusion, broth microdilution, and WGS. Concordance was calculated between pairs of susceptibility testing methods as follows: number of isolates classified identically by the 2 testing methods for each timepoint, divided by the number of isolates tested at that timepoint. Discordance was calculated as follows: number of isolates classified differently by the 2 testing methods for each timepoint, divided by the number of isolates tested at that timepoint.ResultsConcordance between testing methods ranged from 42.3% to 100%, depending on antimicrobial evaluated, timing of sample collection, and testing method used. Very major errors were identified in up to 7.7% of classifications whereas minor errors were seen in up to 50% of classifications depending on antimicrobial evaluated, timing of sample collection, and testing method used.Conclusions and Clinical ImportanceOur results show that discrepancies in the results of different susceptibility testing methods occur and suggest a need for greater harmonization of susceptibility testing methods.

The assessment of skin sensitizing properties of chemicals has moved away from animal methods to new approach methodologies (NAM), guided by qualitative mechanistic understanding operationalized in an adverse outcome pathway (AOP). As with any AOP, the molecular initiating event (MIE) of covalent binding of a chemical to skin proteins is particularly important. This MIE has been modelled by several test methods by measuring the reaction of a test chemical with model peptides in chemico. To better understand the similarities and differences, a data repository with publicly available data for the direct peptide reactivity assay (DPRA), amino acid derivative reactivity assay (ADRA) and kinetic DPRA (kDPRA), as well as the peroxidase peptide reactivity assay (PPRA) was assembled. The repository comprises 260 chemicals with animal and human reference data, data on four relevant physicochemical properties, and between 161 to 242 test chemical results per test method. First, an overview of the experimental conditions of the four test methods was compiled allowing to readily compare them. Second, data analyses demonstrated that the test methods’ predictivity was consistently reduced for poorly watersoluble chemicals and that the DPRA and ADRA can be used interchangeably. It also revealed new categorization thresholds for the DPRA and ADRA that are potentially relevant for strategic uses. In summary, a detailed assessment of reactivity test methods is provided, highlighting their potential and limitations. The results presented are intended to stimulate scientific discussion around test methods modelling the MIE of the skin sensitization AOP.

The assessment of skin sensitizing properties of chemicals has moved away from animal methods to new approach methodologies (NAM), guided by qualitative mechanistic understanding operationalized in an adverse outcome pathway (AOP). As with any AOP, the molecular initiating event (MIE) of covalent binding of a chemical to skin proteins is particularly important. This MIE has been modelled by several test methods by measuring the reaction of a test chemical with model peptides in chemico. To better understand the similarities and differences, a data repository with publicly available data for the direct peptide reactivity assay (DPRA), amino acid derivative reactivity assay (ADRA) and kinetic DPRA (kDPRA), as well as the peroxidase peptide reactivity assay (PPRA) was assembled. The repository comprises 260 chemicals with animal and human reference data, data on four relevant physicochemical properties, and between 161 to 242 test chemical results per test method. First, an overview of the experimental conditions of the four test methods was compiled allowing to readily compare them. Second, data analyses demonstrated that the test methods’ predictivity was consistently reduced for poorly watersoluble chemicals and that the DPRA and ADRA can be used interchangeably. It also revealed new categorization thresholds for the DPRA and ADRA that are potentially relevant for strategic uses. In summary, a detailed assessment of reactivity test methods is provided, highlighting their potential and limitations. The results presented are intended to stimulate scientific discussion around test methods modelling the MIE of the skin sensitization AOP.

Comparison of Two Different (Quasi-) Dynamic Testing Methods for the Performance Evaluation of a Linear Fresnel Process Heat Collector