Structural-acoustic coupling and psychophysical effects in the active control of noise in vehicles

Active noise control systems offer a potential method of reducing the weight of passive acoustic treatment and, therefore, increasing vehicles' fuel efficiency. These can be particularly cost-efficient if integrated with the entertainment system. A combined system is presented employing feedforward control of engine noise and feedback control of road noise, using a `modal' error signal. Due to the dependence of the feedback system on the modal response of the vehicle cabin, the influence of structural-acoustic coupling on this response and the consequent effects on the control performance are investigated. Simulations of the performance of the control systems in rigid and non-rigid enclosures show that the feedforward component is largely unaffected by structural-acoustic coupling, whilst the modal feedback performance is reduced by 3 dB due to the shift in the frequency of the targeted acoustic mode. The simulation results are confirmed through experiments conducted in a structural-acoustic coupled enclosure

Adios to Paper Journals—Removed and Recycled—One Mile Long and 75 Tons

This presentation uses Appalachian State University’s experiences as a stimulus for discussing how we have, and others may, successfully remove in a single swoop several thousand linear feet of little used bound periodicals. This effort opens library areas for new services and spaces. The program will be a resource and guide to others interested in large‐scale deaccessioning projects and includes three deaccessioning projects using online back files from 1) JSTOR; 2) ScienceDirect, Wiley, and Sage; and 3) journals outside of these packages

Evaluated, Removed, and Recycled—The Tale of Two Deaccession Projects Across the Disciplines

How have two midsized public university libraries approached large‐scale weeding projects in their monograph and bound periodical collections? Space is at a premium in academic libraries as new roles combine and compete with traditional ones. How can the collection be refreshed to promote more use? Where will more collaboration and creative spaces be housed? How does a midsized library refine the collection to bring better campus alignment? How should the project begin? Who should be involved in planning? How can campus faculty be included in the deaccessioning process? How is the campus perception of the project handled? What should be kept, what sent off‐site, and what discarded? What do you do with all of those discarded books and journals? How can the libraries work with campus sustainability goals? Do ebooks play a part in what you keep and discard? How are different discipline areas handled when the book is valued differently? Are there useful guidelines like CREW (Continuous Review Evaluation and Weeding) that are applicable

Characterization of Transient Noise in Advanced LIGO Relevant to Gravitational Wave Signal GW150914

On 14 September 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal

Inflation from Extra Dimensions

A gravity-driven inflation is shown to arise from a simple higher dimensional universe. In vacuum, the shear of $n>1$ contracting dimensions is able to inflate the remaining three spatial dimensions. Said another way, the expansion of the 3-volume is accelerated by the contraction of the $n$-volume. Upon dimensional reduction, the theory is equivalent to a four dimensional cosmology with a dynamical Planck mass. A connection can therefore be made to recent examples of inflation powered by a dilaton kinetic energy. Unfortunately, the graceful exit problem encountered in dilaton cosmologies will haunt this cosmology as well.Comment: 15 pages, LaTeX file, 4 Figure

String-localized quantum fields from Wigner representations

In contrast to the usual representations of of the Poincar\'e group of finite spin or helicity the Wigner representations of mass zero and infinite spin are known to be incompatible with pointlike localized quantum fields. We present here a construction of quantum fields associated with these representations that are localized in semi-infinite, space-like strings. The construction is based on concepts outside the realm of Lagrangian quantization with the potential for further applications.Comment: References, some text and an appendix adde

Epidemiological information in sheep health management

We use epidemiology whenever we consider the management of sheep health. To measure a disease, we need a precise and unique case definition and we often use diagnostic tests to assist in defining a disease. Diagnostic tests are not always accurate. Thus, it is necessary to consider the decisions that will be taken, based on the result of testing, in order to decide the most useful approach to interpret a test based on its test sensitivity and specificity and the prevalence of the disease in a flock. This is particularly important when decisions on culling or selection of sheep to attain, e.g. freedom from disease, are made on the basis of test results. Infectious diseases spread within and between flocks in a variety of ways; brought-in sheep are the most likely source for introduction of a new pathogen or strain of a pathogen. When a pathogen enters a naïve flock, it spreads through susceptible sheep and persists in the flock, whilst there are susceptible sheep that can be infected. Pathogens use a variety of techniques to persist, including changes in the pathogen itself, alterations in infected hosts enabling them to remain infectious for prolonged periods or to be re-infected, persistence in other host species or in the environment. We need to consider these strategies to decide whether elimination or control of a particular pathogen is more likely to be effective. Whatever the flock control strategy, treatment of diseased individuals is essential for their welfare and can also protect the rest of the flock, if treatment reduces the infectious period. Decisions on management of disease are based on our knowledge of the flock and its management and the evidence base for various control strategies. There are now formal techniques for evaluating the evidence base that can assist in evaluating evidence. One area where we need to evaluate evidence is on cause. It is not possible to prove anything, but we can use the weight of evidence to evaluate likely cause. There are nine aspects of association with which we can evaluate a piece of evidence; these are: strength, consistency, specificity, temporality, dose–response, plausibility, coherence, experiment and analogy

The concentration-discharge slope as a tool for water quality management

Recent technological breakthroughs of optical sensors and analysers have enabled matching the water quality measurement interval to the time scales of stream flow changes and led to an improved understanding of spatially and temporally heterogeneous sources and delivery pathways for many solutes and particulates. This new ability to match the chemograph with the hydrograph has promoted renewed interest in the concentration-discharge (c-q) relationship and its value in characterizing catchment storage, time lags and legacy effects for both weathering products and anthropogenic pollutants. In this paper we evaluated the stream c-q relationships for a number of water quality determinands (phosphorus, suspended sediments, nitrogen) in intensively managed agricultural catchments based on both high-frequency (sub-hourly) and long-term low-frequency (fortnightly-monthly) routine monitoring data. We used resampled high-frequency data to test the uncertainty in water quality parameters (e.g. mean, 95th percentile and load) derived from low-frequency sub-datasets. We showed that the uncertainty in water quality parameters increases with reduced sampling frequency as a function of the c-q slope. We also showed that different sources and delivery pathways control c-q relationship for different solutes and particulates. Secondly, we evaluated the variation in c-q slopes derived from the long-term low-frequency data for different determinands and catchments and showed strong chemostatic behaviour for phosphorus and nitrogen due to saturation and agricultural legacy effects. The c-q slope analysis can provide an effective tool to evaluate the current monitoring networks and the effectiveness of water management interventions. This research highlights how improved understanding of solute and particulate dynamics obtained with optical sensors and analysers can be used to understand patterns in long-term water quality time series, reduce the uncertainty in the monitoring data and to manage eutrophication in agricultural catchments