7,181 research outputs found

    Suspension Testing of 3 Heavy Vehicles - Methodology and Preliminary Frequency Analysis

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    Three air-sprung heavy vehicles (HVs) were instrumented and tested on typical suburban and highway road sections at typical operational speeds. The vehicles used were a tri-axle semi-trailer towed with a prime mover, an interstate coach with 3 axles and a school bus with 2 axles. The air springs (air bags) of the axle/axle group of interest were configured such that they could be connected using either standard longitudinal air lines or an innovative suspension system comprising larger-than-standard longitudinal air lines. Data for dynamic forces on axles, wheels and chassis were gathered for the purposes of: analysis of the relative performance of the HVs for the two sizes of air lines; informing the QUT/Main Roads project Heavy vehicle suspensions – testing and analysis; and providing a reference source for future projects. This reports sets down the methodology and preliminary results of the testing carried out. Accordingly, Fast-Fourier plots are provided to show indicative frequency spectra for HV axles, wheel forces and air springs during typical use. The results are documented in Appendices 3 to 5. There appears to be little or no correlation between dynamic forces in the air springs and the wheel forces in the HVs tested. Axle-hop at frequencies between 10-15 Hz predominated for unsprung masses in the HV suspensions tested. Air-spring forces are present in the sub-1.0 Hz to approximately 2 Hz frequency range. With the qualification that only one set of data from each test speed is presented herein, in general, the peaks in the frequency spectra of the body-bounce forces and wheel forces were reduced for the tests with the larger longitudinal air lines. More research needs to be done on the load sharing mechanisms between axles on air-sprung HVs. In particular, how and whether improved load sharing can be effected and whether better load sharing between axles will reduce dynamic wheel and chassis forces. This last point, in particular, in relation to the varied dynamic measures used by the HV testing community to compare different suspension types

    FARM POLICY EXTENSION WORK

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    Teaching/Communication/Extension/Profession,

    Landau spectrum and line broadening in real metals

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    Novel techniques for the development of latent fingermarks

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    The scientific study of fingerprints/fingermarks—dactyloscopy—is one of the most important fields in forensic science today. Fingermarks are amongst the most common type of evidence recovered from crime scenes and are arguably the most valued due to the fact that they are, unlike deoxyribonucleic acid (DNA), completely unique to an individual. Fingermarks recovery techniques are constantly evolving and new reagents are always being sought. This project aims to develop and access new fingermark enhancement procedures. The efficacy of an ethanoic solution of phosphomolybdic acid, has been investigated as a latent fingermark enhancement reagent, primarily on porous substrates. After treating samples and exposing them to ultraviolet radiation, the phosphomolybdic acid solution was shown to develop fingermarks to a high quality. Unlike the common amino acid reagents used for the enhancement of fingermarks on porous substrates, ninhydrin and 1,8-diazafluoren-9-one, phosphomolybdic acid stains a range of other compounds found within fingermark deposits, including lipids. The lysochrome diazo dye Oil Red O was used for comparative purposes due to its application in staining some of the same components of fingermark residues that phosphomolybdic acid would be proposed for. Initial results indicate that phosphomolybdic acid is comparable to Oil Red O at developing fingermarks on porous surfaces and may also have applications on non-porous surfaces. A systematic evaluation of solvent carriers was conducted, and whilst many solvents were insufficient, others did show some potential. Primary alcohols such as ethanol, methanol and propan-1-ol all developed fingermarks with identifiable ridge detail. Attempts to mix phosphomolybdic acid with other reagents which react with different fingermark constituents than those phosphomolybdic acid targets were, for the most part unsuccessful. However, not entirely ruled out. Many substrates were tested to observe which developed fingermarks when treated with the phosphomolybdic acid solution. Whilst marks were detected on numerous substrates, paper proved to be the most receptive. Similar stains to the phosphomolybdic acid were tested under the same conditions, however, none were as effective as the phosphomolybdic acid. A non-destructive, non-invasive technique was developed, utilising cuprous metals and their reactions with rubeanic acid. By bringing substrates with fingermarks deposited upon their surface into contact with a copper or copper alloyed plate, it was possible to transfer the fingermark residues to the plate. Forensic gelatin lifters could then be used to lift the marks from the metal plates, these lifted marks could subsequently be treated with a rubeanic acid solution to visualise the fingermarks. The rubeanic acid reacted with the Cu(II) which had been transferred to the fingermark residues to produce a dark product in the pattern of fingermark ridges. The technique was successful at developing fingerprints on semi-porous substrates. The technique was as effective on non-porous substrates, such as glass, but an investigation into the process on porous surfaces was less positive. Attempts to reuse the cuprous metals for the transference of fingermarks after an initial lift resulted in double or ghosted marks being developed, after a thorough wash with soap and water. This was overcome by cleaning with the metal cleaner Brasso. Copper cleaned with Brasso was reused 5 times to show its effectiveness, and adverse effects were minimal. The UK s recent move to polymer banknotes has seen some of the currently used fingermark enhancement techniques for currency potentially become redundant, due to the substrate characteristics of the polymer surfaces. Possessing a non-porous surface with some semi-porous properties, alternate processes are required for polymer banknotes. A preliminary investigation was conducted in to the recovery of fingermarks from polymer notes via vacuum metal deposition using elemental copper. The study successfully demonstrated that fresh latent fingermarks, from an individual donor, could be clearly developed and imaged in the near infrared. By varying the deposition thickness of the copper, the contrast between the fingermark minutiae and the substrate could be readily optimised. Where the deposition thickness was thin enough to be visually indistinguishable, forensic gelatin lifters could be used to lift the fingermarks. These lifts could then be treated with rubeanic acid to produce a visually distinguishable mark. The technique has shown enough promise that it could be effectively utilised on other semi- and non-porous substrates. A follow up group study was less effective than the aforementioned initial study. Many samples were processed using the vacuum metal deposition; incorporating a comparison study between copper and the gold/zinc standard and a depletion trial. However, when imaging was attempted a week after treatment, the results experienced before were unable to be replicated. Attempts to recover samples of radioactive nickel isotope from metal substrates using forensic gel lifters were initially unexceptional. Wipe tests were more successful at recovering the isotope. Experimentation using some non-metallic substrates was more fruitful, the gel lifters were able to recover the radioisotope more readily. Autoradiography showed that, although a weak beta emitter, nickel could be imaged when in sufficient quantities. By using nickel and a short half-life isotope of phosphorus in conjunction with patterned stamps and patterned deposits it was possible to image these patterns by autoradiography of the gels used to lift from the substrates these were deposited upon. These autoradiography images showed enough detail to warrant attempts with a synthetic finger, however, the imaging was insufficient to image the fine details of the friction ridges. Fingermarks deposited on the surface of agar gels showed bacterial growth after incubation for 24 hours. Aseptic transfer of bacterial colonies to fresh agar plates in a typical streak pattern were fruitful. Further transference to a nutrient broth were effective, however, attempts to seed bacterial agar plates for use in inhibition tests were unsuccessful. Overall, phosphomolybdic acid proved to be relatively effective, being able to develop fingermarks on a number of substrates. The copper transfer method, although, less fruitful than PMA showed promise. This lead to the idea of gel lifting from copper VMD treated polymer banknotes which was much more effective. Although, the radioactive and biological techniques showed promise, they were unfortunately unsuccessful at developing fingermarks. A number of the techniques evaluated and developed were successful enough to be published in forensic journals

    The proteomic landscape of microglia in health and disease

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    Microglia are the resident immune cells of the central nervous system (CNS) and as such play crucial roles in regulating brain homeostasis. Their presence in neurodegenerative diseases is known, with neurodegeneration-associated risk genes heavily expressed in microglia, highlighting their importance in contributing to disease pathogenesis. Transcriptomics studies have uncovered the heterogeneous landscape of microglia in health and disease, identifying important disease-associated signatures such as DAM, and insight into both the regional and temporal diversity of microglia phenotypes. Quantitative mass spectrometry methods are ever increasing in the field of neurodegeneration, utilised as ways to identify disease biomarkers and to gain deeper understanding of disease pathology. Proteins are the main mechanistic indicators of cellular function, yet discordance between transcript and proteomic findings has highlighted the need for in-depth proteomic phenotypic and functional analysis to fully understand disease kinetics at the cellular and molecular level. This review details the current progress of using proteomics to define microglia biology, the relationship between gene and protein expression in microglia, and the future of proteomics and emerging methods aiming to resolve heterogeneous cell landscapes

    English Studies as a Site for Healing: A Conversation about Place-Based and Indigenous Pedagogies in the English Classroom

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    This article summarizes a roundtable discussion from the 2016 Alaska Native Studies Conference among professors and students from two English Studies courses at the University of Alaska Anchorage: History of the English Language and History of Rhetoric. Jennifer and Heather discuss how the courses are traditionally taught and how they redesigned the courses to incorporate place-based and indigenous pedagogies. Then, Tayler, Samantha, Hailey, and Arlo--students from a range of backgrounds who took one or both of the classes--describe how the courses encouraged them to develop critical perspectives, build new knowledge through undergraduate research, and experience personal and professional transformations that led to advocacy. The dialogue provides a range of pedagogical perspectives and considers English Studies as a potential site for cultural and historical healing.Ye

    Know Your Land Program for South Dakota

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    A systematic study of the soil is the basic tool for determining the capabilities and limitations of land. Land judging is used to teach and promote a better understanding of soils through a study of the physical properties of the soil and to show how to use these properties in determining proper land use. Most of the characteristic. s that are used to identify soils can be determined in the field

    Methods for estimating directional wave spectra from multi-element arrays

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    1. Introduction The Fourier wavenumber-frequency spectrum of a scalar variable η, with zero mean, is defined

    Observations of the power and directional spectrum of ocean surface waves

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    Estimates of the power spectrum and directional spectrum of oceanic surface waves were obtained from data taken during the Barbados Oceanographic and Meteorological Experiment (BOMEX). Wind speeds ranged from 5 to 10 m s-1 throughout the month\u27s duration of the experiment...
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