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Real Time Systems with Nonpreemptive Priorities and Ample Maintenance Facilities

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Journal of Computer and Communications 2015年第7期3卷 32-45页

作者： Joseph Kreimer edward ianovsky Department of Industrial Engineering and Management Ben-Gurion University of the Negev Beersheba Israel RAVAL ACS Ltd. Beersheba Israel

We consider a real time data acquisition and processing multiserver system with identical servers (such as unmanned aerial vehicles, machine controllers, overhearing devices, medical monitoring devices, etc.) which can be maintained/programmed for different kinds of activities (e.g. passive or active). This system provides a service for real time tasks arriving via several channels (such as surveillance regions, assembly lines, communication channels, etc.) and involves maintenance. We focus on the worst case analysis of the system with ample maintenance facilities exponentially distributed time to failure and maintenance times. We consider two kinds of models (with and without nonpreemptive priorities) and provide balance equations for steady state probabilities and various performance measures, when both operation and maintenance times are exponentially distributed.

关键词： Performance Priority Queueing Real Time System Unmanned Aerial Vehicles

Mini-Review:Green sustainable processes using supercritical fluid carbon dioxide

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Journal of Environmental Sciences 2009年第6期21卷 720-726页

作者： RAMSEY edward University of Science and Technology Liaoning

Environmentally benign carbon dioxide offers significant potential in its supercritical fluid phase to replace current reliance on a range of hazardous, relatively expensive and environmentally damaging organic solvents that are used on an extensive global basis. The unique combination of the physical properties of supercritical fluids are being exploited and further researched to continue the development and establishment of high efficiency, compact plant to provide energy and water efficient manufacturing processes. This mini-review is focused on the use and potential applications of supercritical fluid carbon dioxide for a selected range of key and emerging industrial processes as a sustainable alternative to totally eliminate or greatly reduce the requirement of numerous conventional organic solvents. Examples of the industries include： chemical extraction and purification, synthetic chemical reactions including polymerization and inorganic catalytic processes. Biochemical reactions involving enzymes, particle size engineering, textile dyeing and advanced material manufacture provide further illustrations of vital industrial activities where supercritical fluid technology processes are being implemented or developed. Some aspects relating to the economics of sustainable supercritical fluid carbon dioxide processes are also considered.

关键词： supercritical extraction synthesis catalysis enzymes polymerization particles dyeing

High-order schemes for predicting computational aeroacoustic propagation with adaptive mesh refinement

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Acta Mechanica Sinica 2013年第1期29卷 1-11页

作者： edward Peers Xun Huang State Key Laboratory for Turbulence and Complex Systems Department of Aeronautics and Astronautics College of Engineering Peking University

High-order schemes based on block-structured adaptive mesh refinement method are prepared to solve computational aeroacoustic （CAA） problems with an aim at improving computational efficiency. A number of numerical issues associated with high-order schemes on an adaptively refined mesh, such as stability and accuracy are addressed. Several CAA benchmark problems are used to demonstrate the feasibility and efficiency of the approach.

关键词： Adaptive mesh Aeroacoustics High-order schemes

Sustainable oil-in-water analysis using a supercritical fluid carbon dioxide extraction system directly interfaced with infrared spectroscopy

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Journal of Environmental Sciences 2010年第9期22卷 1462-1468页

作者： edward D.Ramsey School of Chemical Engineering University of Science and Technology Liaoning

A direct aqueous supercritical fluid extraction （SFE） system using carbon dioxide provides a sustainable means by which a vast range of industries may continue to depend on well established infrared （IR） techniques to determine oil-in-water. The SFE-IR method provides an environmentally friendly substitute for current national standard IR reference methods for measuring oil-in-water that rely on using increasingly restricted ozone depleting solvents whose manufacture is being phased out in accordance with international law. The SFE-IR analysis of a 500 mL water sample can be accomplished in 15 min. A rapid on-line SFE-IR calibration method has been implemented. With this calibration method, SFE-IR accuracy for determining diesel oil in 500 mL spiked water samples using single wave number measurement was 86.0%-98.8% with precision （RSD） ranging from 2.5%-7.0%. Using a general purpose calculation which involves measuring infrared absorbance values at three different wave numbers, SFE-IR method accuracy for determining diesel oil in 500 mL spiked water samples was 83.7%-92.2% with RSD 1.0%-9.3%. Data is presented that indicates current long established national standard IR reference methods involving three wave number calculations should be reviewed since, without careful consideration, the inclusion of calculated aromatic hydrocarbon species contributions to final oil-in-water concentration values may provide less accurate results.

关键词： oil-in-water supercritical fluid extraction infrared spectroscopy sustainable green technology

Methods for improving thermal tolerance in military personnel prior to deployment

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Military Medical Research 2021年第3期8卷 405-423页

作者： edward Tom Ashworth James David Cotter Andrew edward Kilding Sports Performance Research Institute New Zealand(SPRINZ) Auckland University of Technology17 Antares PlaceRosedaleAuckland 0632New Zealand School of Physical Education Sport and Exercise SciencesUniversity of OtagoDunedinOtago 9016New Zealand

Acute exposure to heat, such as that experienced by people arriving into a hotter or more humid environment, can compromise physical and cognitive performance as well as health. In military contexts heat stress is exacerbated by the combination of protective clothing, carried loads, and unique activity profiles, making them susceptible to heat illnesses. As the operational environment is dynamic and unpredictable, strategies to minimize the effects of heat should be planned and conducted prior to deployment. This review explores how heat acclimation(HA) prior to deployment may attenuate the effects of heat by initiating physiological and behavioural adaptations to more efficiently and effectively protect thermal homeostasis, thereby improving performance and reducing heat illness risk. HA usually requires access to heat chamber facilities and takes weeks to conduct, which can often make it impractical and infeasible, especially if there are other training requirements and expectations. Recent research in athletic populations has produced protocols that are more feasible and accessible by reducing the time taken to induce adaptations, as well as exploring new methods such as passive HA. These protocols use shorter HA periods or minimise additional training requirements respectively, while still invoking key physiological adaptations, such as lowered core temperature, reduced heart rate and increased sweat rate at a given intensity. For deployments of special units at short notice(< 1 day) it might be optimal to use heat re-acclimation to maintain an elevated baseline of heat tolerance for long periods in anticipation of such an event. Methods practical for military groups are yet to be fully understood, therefore further investigation into the effectiveness of HA methods is required to establish the most effective and feasible approach to implement them within military groups.

关键词： Heat acclimation Thermoregulation Heat illness Physiology Human Conditioning Military

On Building Practical Biocomputers for Real-world Applications： Receptacles for Culturing Slime Mould Memristors and Component Standardisation

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Journal of Bionic Engineering 2017年第1期14卷 151-162页

作者： edward Braund Eduardo Reck Miranda Interdisciplinary Centre for Computer Music Research (ICCMR) The House Plymouth University Drake Circus UK PL4 8AA

Our application of bionic engineering is novel： we are interested in developing hybrid hardware-wetware systems for music. This paper introduces receptacles for culturing Physarum polycephalum-based memristors that are highly accessible to the creative practitioner. The myxomycete Physarum polycephalum is an amorphous unicellular organism that has been found to exhibit memristive properties. Such a discovery has potential to allow us to move towards engineering electrical systems that encompass Physarum polycephalum components. To realise this potential, it is necessary to address some of the constraints associated with harnessing living biological entities in systems for real-time application. Within the paper, we present 3D printed receptacles designed to standardise both the production of components and memristive observations. Subsequent testing showed a significant decrease in growth time, increased lifespan, and superior similarity in component-to-component responses. The results indicate that our receptacle design may provide means of implementing hybrid electrical systems for music technology.

关键词： unconventional computing Physarum polycephalum computer music biological computing memristor

Nanosecond laser preheating effect on ablation morphology and plasma emission in collinear dual-pulse laser-induced breakdown spectroscopy

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Plasma Science and Technology 2022年第11期24卷 145-150页

作者： Na LI edward HAREFA Weidong ZHOU Key Laboratory of Optical Information Detection and Display Technology of Zhejiang Zhejiang Normal UniversityJinhua 321004People’s Republic of China

Focus-offset collinear dual-pulse laser-induced breakdown spectroscopy is designed and used to investigate the laser ablation and spectral intensity with an aluminum alloy *** laser crater morphologies and ablation volumes were *** inter-pulse time delay dependent ablation efficiency on a nanosecond laser-heated sample was observed,which was similar to the trend of spectral intensity versus inter-pulse time delay in the delay time less than 3μ*** on the observation,the nanosecond pulse laser preheating effect on subsequent second laser ablation and signal enhancement is discussed,which will be helpful for understanding the ablation and signal enhancement mechanism in the standard collinear DP-LIBS technique.

关键词： enhancement mechanism laser ablation crater morphology target preheating

Optimal slot dimension for skirt support structure of coke drums

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Frontiers of Mechanical Engineering 2018年第4期13卷 554-562页

作者： edward WANG Zihui XIA Department of Mechanical Engineering University of Alberta Edmonton T6G1H9 Canada

The skirt-to-shell junction weld on coke drums is susceptible to fatigue failure due to severe thermal cyclic stresses. One method to decrease junction stress is to add slots near the top of the skirt, thereby reducing the local stiffness close to the weld. The most common skirt slot design is thin relative to its circumferential spacing. A new slot design, which is significantly wider, is proposed. In this study, thermal-mechanical elastoplastic 3-D finite element models of coke drums are created to analyze the effect of different skirt designs on the stress/strain field near the shell-to-skirt junction weld, as well as any other critical stress locations in the overall skirt design. The results confirm that the inclusion of the conventional slot design effectively reduces stress in the junction weld. However, it has also been found that the critical stress location migrates from the shell-to-skirt junction weld to the slot ends. A method is used to estimate the fatigue life near the critical areas of each skirt slot design. It is found that wider skirt slots provide a significant improvement on fatigue life in the weld and slot area.

关键词： coke drum stress analysis cyclic stress fatigue life skirt slots

Petrological implication of wagnerite-Ma5bc in the quartzofeldspathic gneiss, Larsemann Hills, East Antarctica

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Progress in Natural Science:Materials International 2005年第6期15卷 523-529页

作者： edward S. GREW 5790 edward T. Bryand Research Center Department of Earth Sciences Maine 04469-5790 Orono USA University of Maine

Wagnerite-Ma5bc polytype is found in a gneiss associated with cordierite-prismatine-bearing gneiss, northern Stornes Peninsula, Larsemann Hills, East Antarctica. Wagnerite coexists with apatite and both of them are present as rock-forming minerals. Ca depletion is not essential to the formation of wagnerite; sufficient Mg, P and F components, and a relatively low Ca/Mg ratio is critical, otherwise only apatite crystallizes. Strong anatexis of the quartzofeldspathic gneiss of the area results in differentiation and separate enrichment of leuco- and melanocratic components. P and F tend to accumulate in the mafic-rich melanocratic component, and when their abundance reaches certain concentration, wagnerite forms. It is perhaps the chemistry of the setting that controls the appearance of wagnerite, whereas the PT condition is responsible for the variety of wagnerite polytype. A disordered polytype crystallizes at relatively high temperature, then cools down slowly and transforms into one of the ordered polytypes, in this case, the Ma5bc polytype.

关键词： wagnerite-Ma5bc polytype anatexis formation condition volatile components Larsemann Hills.