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Search Results: 1 - 10 of 171929 matches for " Paul H. Riley "
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The Myth of the High-Efficiency External-Combustion Stirling Engine  [PDF]
Paul H. Riley
Engineering (ENG) , 2015, DOI: 10.4236/eng.2015.712068
Abstract: The reported discrepancy between theory and experiment for external combustion Stirling engines is explained by the addition of thermal resistance of the combustion gasses to the standard Carnot model. In these cases, the Stirling engine ideal efficiency is not as is normally reported equal to the Carnot cycle efficiency but is significantly lower. A new equation for ideal Stirling engine efficiency when the heat is obtained through external combustion without pre-heating the air, is presented and results for various fuels tabulated. The results show that petrol and diesel, internal combustion engines (Otto cycle) have a higher ideal efficiency than the Stirling engine. When comparing thermoacoustic engines heated by wood, efficiency should not be quoted as a percentage of the Carnot efficiency, but against a figure 48% lower than Carnot. The effect is not seen with electrically heated rigs, solar or nuclear fission heated engines.
Performance of a Score-Stove with a Kerosene Burner and the Effect of Pressurization of the Working Fluid  [PDF]
Md Ehsan, Manabendra Sarker, Rifath Mahmud, Paul H. Riley
Journal of Power and Energy Engineering (JPEE) , 2015, DOI: 10.4236/jpee.2015.34063
Abstract:

Score-StoveTM a clean-burning cooking stove that also generates electricity was tested using a pressurized kerosene burner. The Score-Stove works on the principle of thermo-acoustics to gen- erate small-scale electricity. The device having hot-end, cold-end and regenerator acts in a way similar to a stirling cycle generating acoustic power, which is then converted to electricity using a linear actuator. It can supply small power for applications such as LED lighting, mobile phone charging and radios particularly in rural areas without grid electricity as well as improving house- hold air pollution. After assessing the needs of the rural communities through a survey, tea-stalls and small restaurants owners were identified as clients with the most potential of using the stove in Bangladesh. Bangladesh University of Engineering and Technology ((BUET) modified a Score- Stove to use both wood and a pressurized kerosene burner of a design that is widely used for cooking in rural areas of Bangladesh. The design was adapted to meet performance needs such as: heating rate, cooking efficiency, energy distribution, electric power generation, exhaust emissions and time taken to boil water using standardized water boiling tests. Performance was also compared with conventional (non-electrically generating) stoves that use a pressurized kerosene burn- er. The Score-Stove performance was then evaluated while increasing the pressure of the sealed working fluid (air in this case) from atmospheric to about 1.4 bar. The pressurization was found to almost double the power generation. An arrangement for utilizing cooling water waste heat was also devised in order to improve the thermal performance of the stove by 18%. Technical deficiencies are documented and recommendations for improvements and future research in order to obtain wider end-user acceptance are made.

Development and Assessment of Thermoacoustic Generators Operating by Waste Heat from Cooking Stove  [PDF]
Baiman Chen, Abdalla A. Yousif, Paul H. Riley, David B. Hann
Engineering (ENG) , 2012, DOI: 10.4236/eng.2012.412113
Abstract: This paper presents the development and assessment of two low-cost, travelling wave, thermoacoustic generators operating by waste heat energy from cooking stove. One powered by waste heat from a propane-driven stove, the other powered by waste heat from a wood-burning stove. The propane-driven thermoacoustic generator was successfully demonstrated to produce approximately 15 watts of electricity using a commercial audio loudspeaker. The wood-burning thermoacoustic generator was successfully constructed and tested to generate a maximum of 22.7 watts of electricity under a pressurised condition. The latter has a high potential to be used by over 1.5 billion people in rural communities for applications such as LED lighting, charging mobile phones or charging a 12V battery. A comprehensive power assessment of the propane-driving generator as well as the development and performance assessment of the wood-burning generator are described throughout this article.
Robust Lane Detection in Shadows and Low Illumination Conditions using Local Gradient Features  [PDF]
Avishek Parajuli, Mehmet Celenk, H. Bryan Riley
Open Journal of Applied Sciences (OJAppS) , 2013, DOI: 10.4236/ojapps.2013.31B014
Abstract: This paper presents a method for lane boundaries detection which is not affected by the shadows, illumination and un-even road conditions. This method is based upon processing grayscale images using local gradient features, characteris-tic spectrum of lanes, and linear prediction. Firstly, points on the adjacent right and left lane are recognized using the local gradient descriptors. A simple linear prediction model is deployed to predict the direction of lane markers. The contribution of this paper is the use of vertical gradient image without converting into binary image(using suitable thre-shold), and introduction of characteristic lane gradient spectrum within the local window to locate the preciselane marking points along the horizontal scan line over the image. Experimental results show that this method has greater tolerance to shadows and low illumination conditions. A comparison is drawn between this method and recent methods reported in the literature.
Gene fusions and gene duplications: relevance to genomic annotation and functional analysis
Margrethe H Serres, Monica Riley
BMC Genomics , 2005, DOI: 10.1186/1471-2164-6-33
Abstract: Multimodular E. coli K-12 proteins were identified from sequence similarities between their component modules and non-fused proteins in 50 genomes and from the literature. We found 109 multimodular proteins in E. coli containing either two or three modules. Most modules had standalone sequence relatives in other genomes. The separated modules together with all the single (un-fused) proteins constitute the sum of all unimodular proteins of E. coli. Pairwise sequence relationships among all E. coli unimodular proteins generated 490 sequence similar, paralogous groups. Groups ranged in size from 92 to 2 members and had varying degrees of relatedness among their members. Some E. coli enzyme groups were compared to homologs in other bacterial genomes.The deleterious effects of multimodular proteins on annotation and on the formation of groups of paralogs are emphasized. To improve annotation results, all multimodular proteins in an organism should be detected and when known each function should be connected with its location in the sequence of the protein. When transferring functions by sequence similarity, alignment locations must be noted, particularly when alignments cover only part of the sequences, in order to enable transfer of the correct function. Separating multimodular proteins into module units makes it possible to generate protein groups related by both sequence and function, avoiding mixing of unrelated sequences. Organisms differ in sizes of groups of sequence-related proteins. A sample comparison of orthologs to selected E. coli paralogous groups correlates with known physiological and taxonomic relationships between the organisms.Eschericia coli remains a useful resource to the genomic community as it provides important knowledge which can be applied to the analysis of most microbial genomes. Its central role devolves from two facts; first, the accumulated results of seven decades of laboratory experimentation have identified the function(s) of over half
Formation of the Ventricles
Catherine A. Risebro,Paul R. Riley
The Scientific World Journal , 2006, DOI: 10.1100/tsw.2006.316
Abstract:
Introducing SLAMBench, a performance and accuracy benchmarking methodology for SLAM
Luigi Nardi,Bruno Bodin,M. Zeeshan Zia,John Mawer,Andy Nisbet,Paul H. J. Kelly,Andrew J. Davison,Mikel Luján,Michael F. P. O'Boyle,Graham Riley,Nigel Topham,Steve Furber
Computer Science , 2014, DOI: 10.1109/ICRA.2015.7140009
Abstract: Real-time dense computer vision and SLAM offer great potential for a new level of scene modelling, tracking and real environmental interaction for many types of robot, but their high computational requirements mean that use on mass market embedded platforms is challenging. Meanwhile, trends in low-cost, low-power processing are towards massive parallelism and heterogeneity, making it difficult for robotics and vision researchers to implement their algorithms in a performance-portable way. In this paper we introduce SLAMBench, a publicly-available software framework which represents a starting point for quantitative, comparable and validatable experimental research to investigate trade-offs in performance, accuracy and energy consumption of a dense RGB-D SLAM system. SLAMBench provides a KinectFusion implementation in C++, OpenMP, OpenCL and CUDA, and harnesses the ICL-NUIM dataset of synthetic RGB-D sequences with trajectory and scene ground truth for reliable accuracy comparison of different implementation and algorithms. We present an analysis and breakdown of the constituent algorithmic elements of KinectFusion, and experimentally investigate their execution time on a variety of multicore and GPUaccelerated platforms. For a popular embedded platform, we also present an analysis of energy efficiency for different configuration alternatives.
Analysis of Criteria for MRI Diagnosis of TMJ Disc Displacement and Arthralgia
Jeffry R. Shaefer,Cara Joy Riley,Paul Caruso,David Keith
International Journal of Dentistry , 2012, DOI: 10.1155/2012/283163
Abstract:
Analysis of Criteria for MRI Diagnosis of TMJ Disc Displacement and Arthralgia
Jeffry R. Shaefer,Cara Joy Riley,Paul Caruso,David Keith
International Journal of Dentistry , 2012, DOI: 10.1155/2012/283163
Abstract: Aims. To improve diagnostic criteria for TMJ disc displacement (DD). Methods. The standard protocol for MRI diagnosis of DD, using a 12 o’clock reference position, was compared to an alternative protocol. The alternative protocol involves the functional relationship between the condyle and articular eminence, using a line perpendicular to the posterior slope of the eminence as a reference for disc position. The disc location was examined using both protocols, and disc diagnoses were compared in their relationship with joint pain. Statistical analyses included value, sensitivity, specificity, odds ratio, and kappa statistic. Results. 58 MRIs were interpreted. 36 subjects reported arthralgia; 22 did not. Both protocols demonstrated significance (standard , alternative ) for the ability to predict arthralgia. The odds of arthralgia increased in DD patients diagnosed by standard methods 9.71 times and in DD diagnosed by alternative means 37.15 times. The diagnostic sensitivity decreased 30% using the alternative versus the standard protocol (0.6389 versus 0.9444), while specificity increased 60% (0.9545 versus 0.3636). Conclusions. A stronger relationship occurs between DD and arthralgia when using a function-based protocol. The alternative protocol correctly identifies subjects without arthralgia, who by standard methods would be diagnosed with DD, as having nondisplaced discs, providing a more clinically relevant assessment of TMJ disc displacement. 1. Introduction 1.1. Background and Significance Temporomandibular joint pain is considered to develop as the result of inflammatory and/or mechanical mechanisms [1]. Gross morphological changes such as deviation in form, disc displacement, adhesions, and osteoarthritic processes can occur with or without the subject’s perceiving pain or dysfunction [2]. When do such findings relate to pain and dysfunction? In Westesson’s summary regarding the imaging diagnosis of TMJ arthralgia he states, “inflammatory changes correlate strongly with the patient’s pain symptoms [and] we are getting closer to imaging the changes that are truly relevant to [these] symptoms” [3]. In his study, he focused on the most symptomatic TMJ in each subject, but found a high number of abnormalities consistent with disc displacement and inflammation in the contralateral joint, as well. These asymptomatic TMJ imaging abnormalities are reminiscent of asymptomatic meniscal and lumbar disc abnormalities often seen in knee and back patients, respectively. This similar imaging conundrum supports the concept that preexisting TMJ disc degeneration
The relationship between star formation rate and radio synchrotron luminosity at 0 < z < 2
Timothy Garn,David A. Green,Julia M. Riley,Paul Alexander
Physics , 2009, DOI: 10.1111/j.1365-2966.2009.15073.x
Abstract: We probe the relationship between star formation rate (SFR) and radio synchrotron luminosity in galaxies at 0 < z < 2 within the northern Spitzer Wide-area Infrared Extragalactic survey (SWIRE) fields, in order to investigate some of the assumptions that go into calculating the star formation history of the Universe from deep radio observations. We present new 610-MHz Giant Metrewave Radio Telescope (GMRT) observations of the European Large-Area ISO Survey (ELAIS)-N2 field, and using this data, along with previous GMRT surveys carried out in the ELAIS-N1 and Lockman Hole regions, we construct a sample of galaxies which have redshift and SFR information available from the SWIRE survey. We test whether the local relationship between SFR and radio luminosity is applicable to z = 2 galaxies, and look for evolution in this relationship with both redshift and SFR in order to examine whether the physical processes which lead to synchrotron radiation have remained the same since the peak of star formation in the Universe. We find that the local calibration between radio luminosity and star formation can be successfully applied to radio-selected high-redshift, high-SFR galaxies, although we identify a small number of sources where this may not be the case; these sources show evidence for inaccurate estimations of their SFR, but there may also be some contribution from physical effects such as the recent onset of starburst activity, or suppression of the radio luminosity within these galaxies.
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