Conversion and performance evaluation of a hydrogen powered Ford F-250 pickup truck

The following thesis details all design, fabrication and analysis necessary for the conversion of a Compressed Natural Gas (CNG) powered full size pickup truck to run on compressed hydrogen gas. As an industry for hydrogen powered vehicles develops, adherence to a specified set of safety regulations is necessary to ensure the safety of vehicle end users. Currently accepted standards for hydrogen vehicle safety follow regulations put forth by NFPA for CNG powered vehicles. The design of the fuel system follows applicable hydrogen and CNG regulations. A potentially revolutionary fuel delivery system that consolidates a gaseous fuel injector and a spark plug is to be employed on this vehicle; A device of this type has the potential to greatly simplify future hydrogen vehicle conversions. Electronic sensors implemented in the system provide a means for leak detection around the location of the tanks. A fuel cell and a bank of three super capacitors have been installed to replace the alternator and battery. Replacing the alternator with a fuel cell converts the chemical energy of the hydrogen fuel already stored on the vehicle to electrical energy more efficiently than using the engine to convert chemical energy into mechanical energy then into electrical energy. The fuel cell was a 1.2 kW PEM stack type produced by Ballard. Computer control of the engine is accomplished via the factory computer already installed in the truck. Programming a fuel table custom to hydrogen is accomplished via an aftermarket reprogramming module and complementing software. The initial fuel table is determined from thermodynamic relations pertaining to compressible flow. Preliminary ignition timing tables were obtained from approximations of hydrogen flame speed scaled to the density of the air fuel mixture. Included in this thesis are all design criteria, analysis and recommended methods for modeling engine performance

Supplementary feeding of weaner sheep at Esperance

Cereal grains, particularly barley, have been the usual supplement fed to weaner sheep during summer and autumn along Western Australia\u27s south coast. This area is a major barley producer, and weather-damaged and other feed quality grain have a ready use. High protein lupin seed, and to a lesser extent silage, have gained wide acceptance recently as alternative supplements. This article discusses the results of the first two of a series of supplementary feeding experiments at Esperance Downs Research Station

Bacteria classification using Cyranose 320 electronic nose

Background An electronic nose (e-nose), the Cyrano Sciences' Cyranose 320, comprising an array of thirty-two polymer carbon black composite sensors has been used to identify six species of bacteria responsible for eye infections when present at a range of concentrations in saline solutions. Readings were taken from the headspace of the samples by manually introducing the portable e-nose system into a sterile glass containing a fixed volume of bacteria in suspension. Gathered data were a very complex mixture of different chemical compounds. Method Linear Principal Component Analysis (PCA) method was able to classify four classes of bacteria out of six classes though in reality other two classes were not better evident from PCA analysis and we got 74% classification accuracy from PCA. An innovative data clustering approach was investigated for these bacteria data by combining the 3-dimensional scatter plot, Fuzzy C Means (FCM) and Self Organizing Map (SOM) network. Using these three data clustering algorithms simultaneously better 'classification' of six eye bacteria classes were represented. Then three supervised classifiers, namely Multi Layer Perceptron (MLP), Probabilistic Neural network (PNN) and Radial basis function network (RBF), were used to classify the six bacteria classes. Results A [6 × 1] SOM network gave 96% accuracy for bacteria classification which was best accuracy. A comparative evaluation of the classifiers was conducted for this application. The best results suggest that we are able to predict six classes of bacteria with up to 98% accuracy with the application of the RBF network. Conclusion This type of bacteria data analysis and feature extraction is very difficult. But we can conclude that this combined use of three nonlinear methods can solve the feature extraction problem with very complex data and enhance the performance of Cyranose 320

Measuring Lead Concentrations of Vacant Lots in the Tree Street Neighborhood of Lewiston, ME

High levels of lead contamination have detrimental health implications for communities, with the most profound impacts of lead poisoning affecting young children. The City of Lewiston, Maine, is home to a disproportionate amount of reported lead poisoning cases as compared to the rest of the state. Within Lewiston, the downtown “Tree Street” neighborhood contains 72% of all reported lead-poisoning cases in the city, signifying a need to identify the source(s) of lead exposure and minimize the impact of lead contamination on Tree Street residents. In collaboration with Healthy Neighborhoods, we identified 19 vacant lots in the Tree Street neighborhood to test for soil lead contamination. With the aim of quantifying and contextualizing the distribution of lead across the vacant lots, we took 9 composite samples from each lot and tested them for lead using an X-Ray Fluorescence (XRF) gun. The XRF gun provided an elemental analysis of each sample in parts per million (ppm). Using this data, we created maps showing the geographic distribution of lead across the neighborhood and each site. We also created graphs showing the concentration distribution across and within sites. The most concerning site (site 17) had an average lead concentration of 634 ppm and a maximum value of 2370 ppm, which surpasses the Environmental Protection Agency (EPA) safety threshold of 400ppm for bare soil in play areas. Along with identifying the extent and distribution of lead contamination in the vacant lots, we considered which types of lead remediation are best suitable for minimizing exposure to lead contamination in the Tree Street neighborhood. In this report, we examine the remediation strategies of phytoremediation, soil caps and raised beds, and soil amendments. After a comprehensive discussion of these three strategies in relation to the criteria of cost, feasibility, and effectiveness, we determine which strategies are most suitable for use in the lead-contaminated Tree Street neighborhood vacant lots. We recommend the use of sunflower phytoremediation as our primary remediation technique. We also recommend the use of certain soil amendments as a secondary remediation technique; the use of this strategy, however, is contingent on whether Healthy Neighborhoods and the City of Lewiston have access to the appropriate equipment necessary for the processing of these amendments. Finally, we end our report with recommendations for next steps for Healthy Neighborhoods and the City of Lewiston in continuing the project of creating a lead-free community

Make the adder count: population trends from a citizen science survey of UK adders

Concern has been growing about the status of UK adder populations, with expert opinion reporting widespread declines. Assessing the true scale of these declines, however, has been hampered by a lack of quantitative data. Make the Adder Count began in 2005 as a national surveillance programme collecting standardised counts of adders lying-out after emerging from hibernation. 260 sites have contributed data, confirming a significant decline, on average, across sites with small populations, while the few with large populations (<10 % of sites) are weakly increasing. If these trends continue, within 15‒20 years, adders will be restricted to a few large population sites, significantly increasing the extinction risk for this priority species in the UK. Public pressure/disturbance was reported as the most frequent negative factor affecting sites, followed by habitat management and habitat fragmentation. Negative impacts from habitat management were reported almost as frequently as positive impacts, suggesting many management plans do not adequately consider the requirements of adders. The dataset also demonstrated earlier emergence among males, in warmer springs and at more northerly sites

TaDA Live: Compositional Reasoning for Termination of Fine-grained Concurrent Programs

We introduce TaDA Live, a separation logic for reasoning compositionally about the termination of blocking fine-grained concurrent programs. The logic contributes several innovations to obtain modular rely/guarantee style reasoning for liveness properties and to blend them with logical atomicity. We illustrate the subtlety of our specifications and reasoning on some paradigmatic examples.Comment: 24 pages, 97 pages including appendi

Exact Separation Logic

Over-approximating (OX) program logics, such as separation logic (SL), are used for verifying properties of heap-manipulating programs: all terminating behaviour is characterised, but established results and errors need not be reachable. OX function specifications are thus incompatible with true bug-finding supported by symbolic execution tools such as Pulse and Pulse-X. In contrast, under-approximating (UX) program logics, such as incorrectness separation logic, are used to find true results and bugs: established results and errors are reachable, but there is no mechanism for understanding if all terminating behaviour has been characterised. We introduce exact separation logic (ESL), which provides fully-verified function specifications compatible with both OX verification and UX true bug-funding: all terminating behaviour is characterised, and all established results and errors are reachable. We prove soundness for ESL with mutually recursive functions, demonstrating, for the first time, function compositionality for a UX logic. We show that UX program logics require subtle definitions of internal and external function specifications compared with the familiar definitions of OX logics. We investigate the expressivity of ESL and, for the first time, explore the role of abstraction in UX reasoning by verifying abstract ESL specifications of various data-structure algorithms. In doing so, we highlight the difference between abstraction (hiding information) and over-approximation (losing information). Our findings demonstrate that, expectedly, abstraction cannot be used as freely in UX logics as in OX logics, but also that it should be feasible to use ESL to provide tractable function specifications for self-contained, critical code, which would then be used for both verification and true bug-finding