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81.
Andrew Wallace 《国际生产研究杂志》2013,51(4):709-726
Automated Guided Vehicle (AGV) systems are complex to design and to implement. Inefficiencies become difficult to avoid or even to control. This paper presents the theory behind a novel agent based AGV controller that aims to control the flow of AGVs in an effective manner and, therefore, overcome the inefficiencies that can be found in complex designs. Agents are simple entities that interact with other agents to produce an emergent behaviour that is not explicitly programmed into them. The AGV controller presented uses agents as traffic managers to allow access to points and segments in the guide path. Each agent has a rule base that it uses to assess the enquiries that it receives from an AGV. Each enquiry is evaluated only at the smallest possible part of the guide path rather than the entire guide path. AGVs are then able to allocate segments and points on their paths depending on the result of each enquiry. Simulation experiments were used to test the controller and an overview is presented. 相似文献
82.
Dave Randall 《Computer Supported Cooperative Work (CSCW)》2016,25(4-5):409-423
Tenenberg, Roth, and Socha’s paper “From I-awareness to we-awareness in CSCW” is, or should be, of special significance to those in the CSCW and HCI communities with more than a passing interest in the theoretical issues that underpin our work. It can be argued, and I would be a proponent of this view, that fundamental intellectual disagreements too seldom get an airing in our community, perhaps because it is in large part conference driven. Because of this, underlying perspectival disagreements can appear rather arcane. One of the great merits of the contributions to this special issue, I hope and believe, is that they will appear less so after careful reading. 相似文献
83.
Wallace Manheimer 《Journal of Fusion Energy》2016,35(3):519-523
This article presents and explores three heretical thoughts regarding fusion and climate. First, the only way that fusion can contribute to midcentury power is by switching its goal from pure fusion, to fusion breeding. Doing so could lead to a sustainable, carbon free, environmentally and economically viable, midcentury infrastructure, with little or no proliferation risk, which could provide terawatts of power for the world. Second, while CO2 input to the atmosphere may, at some point, become a concern to the earth’s climate, an Internet search shows that there is no evidence that we are anywhere near that point now and likely will not be before midcentury at the earliest. Third, those who insist on a nearly immediate end to CO2 input into the atmosphere, are little different from others who have caused panics at various times in American history. The timing could be serendipitous; the time necessary to develop fusion breeding could well match up to the time when it is needed so as to avoid harm to the earth’s climate and/or depletion of finite energy resources. 相似文献
84.
Vuchinich Rudy; Wallace Dennis; Milby Jesse B.; Schumacher Joseph E.; Mennemeyer Stephen; Kertesz Stefan 《Canadian Metallurgical Quarterly》2009,17(3):165
Clinical trials with cocaine-dependent outpatients have found a strong relation between in-treatment and follow-up abstinence, and the strength of this relation is constant across treatment conditions with variable efficacy in generating abstinence. The authors conducted secondary analyses of data from 3 clinical trials to determine whether this relation generalizes to cocaine-dependent homeless persons. The 3 trials (total N = 543) were conducted in a community health care facility for homeless people. The 7 treatment arms across the 3 trials were combinations of day treatment, abstinence-contingent housing, and vocational training. Drug use was measured with urine toxicology testing. Consecutive weeks of abstinence during treatment were strongly related to abstinence at the 12-month follow-up, whether or not missing 12-month data were included in the analysis. The treatment arms differed in their efficacy in generating abstinence, but the relation between in-treatment and follow-up abstinence did not differ across treatment arms. These results replicate earlier reports of these relations and extend them to a population of homeless people. The lack of differences between treatment arms in the in-treatment–follow-up abstinence relation implies that that relation is independent of the treatment-specific intervention components that generate group differences in abstinence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
The study focuses on hydrogen production from steam reforming of glycerol over nickel based catalyst promoted by zirconia and supported over ceria. Catalyst was prepared by the wet-impregnation method and characterized by BET surface area analysis, X-ray diffraction technique and scanning electron microscopy (SEM) analysis. The performance of the catalyst was evaluated in terms of hydrogen yield, selectivity and glycerol conversion at 700 °C in a tubular fixed bed reactor. The effect of glycerol concentration in feed, space time (W/FAO), temperature and time on stream (TOS) was analyzed for the catalyst Ni–ZrO2/CeO2 which showed the complete conversion of glycerol and high H2 yield that corresponds to 3.95 mol of H2 out of 7 mol. Thermodynamic analysis was also carried out using Aspen HYSYS for system having glycerol concentration 10 wt% and 20 wt% and experimental results were compared with thermodynamics. Kinetic study was carried out for the steam reforming of glycerol over Ni–ZrO2/CeO2 catalyst using the power law model. The values of activation energy and order of reaction were found to be 43.4 kJ/mol and 0.3 respectively. 相似文献
86.
让周遭的系统能够自动感测环境变化并做出反应,势必将对于人类的生活造成重大改变。无线传感器网络是多个分布式传感器实作(节点)组成的系统,能够共同透过相互无线通信的方式响应实体变化。本文将重点介绍节点的最新进展,并推广对于系统层级设计方法的需求。 相似文献
87.
Solvent Influence on the Hydrodeoxygenation of Guaiacol over Pt/SiO2 and Pt/H‐MFI 90 Catalysts
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Melanie Hellinger Hudson Wallace Pereira de Carvalho Sina Baier Loubna Gharnati Jan‐Dierk Grunwaldt 《化学,工程师,技术》2015,87(12):1771-1780
Second generation biofuels are produced in the bioliq® process at the Karlsruhe Institute of Technology via gasification of pyrolysis oil and synthesis of gasoline from the emerging synthesis gas. An alternative strategy is the direct upgrading of the pyrolysis oil by hydrodeoxygenation (HDO). The present study reports on the HDO of guaiacol as one of the phenolic compounds strongly abundant in such mixtures. Special focus was laid on the solvent influence using Pt‐based catalysts. Higher HDO ability was seen using nonpolar solvents and acidic supports. Characterization of the catalysts before and after the test showed that the solvent did not only influence the reactivity, but also the catalyst stability. 相似文献
88.
The concept of territoriality and its relationship to the focus and substance of spatial planning is the subject of much interest at the present time and this paper seeks to contribute to the debate by stepping into the sea. The first part of the paper establishes a framework for considering the spatial planning implications of changing conceptions of territoriality, outlining key sources of territorial innovation and their implications in terms of the development of new units and styles of governance, new challenges for planning practice, and the potential for feedback informing the development of planning theory. The application of the framework is then illustrated in the second part of the paper with reference to the emerging field of maritime spatial planning and in particular to the pioneering work that is being undertaken in Europe. This work is testing established notions of territoriality by highlighting the strong and growing connections between the land and the sea. Here some of the key implications for future spatial planning practice are identified. These indicate that there is a growing recognition of the need for innovation in the territorial units of governance in maritime regions and in the themes, processes and methods of spatial planning in these areas. The paper concludes with some observations on the implications of these findings for the theory of spatial planning. 相似文献
89.
Evaluation of the use of adsorbent materials in the removal of nitrogen compounds from gas oil as a pre‐treatment for feeds for fluid catalytic cracking units
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90.
Effect of Mechanical Constraint on Domain Reorientation in Predominantly {111}‐Textured Lead Zirconate Titanate Films
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Giovanni Esteves Margeaux Wallace Raegan Johnson‐Wilke Chris M. Fancher Rudeger H. T. Wilke Susan Trolier‐McKinstry Jacob L. Jones 《Journal of the American Ceramic Society》2016,99(5):1802-1807
Ferroelectric/ferroelastic domain reorientation was measured in 2.0 μm thick tetragonal {111}‐textured PbZr0.30Ti0.70O3 thin films using synchrotron X‐ray diffraction (XRD). Lattice strain from the peak shift in the 111 Bragg reflection and domain reorientation were quantified as a function of applied electric field amplitude. Domain reorientation was quantified through the intensity exchange between the 112 and 211 Bragg reflections. Results from three different film types are reported: dense films that are clamped to the substrate (as‐processed), dense films that are partially released from the substrate, and films with 3% volume porosity. The highest amount of domain reorientation is observed in grains that are misoriented with respect to the {111} preferred (domain engineered) orientation. Relative to the clamped films, films that were released from the substrate or had porosity exhibited neither significant enhancement in domain reorientation nor in 111 lattice strain. In contrast, similar experiments on {100}‐textured and randomly oriented films showed significant enhancement in domain reorientation in released and porous films. Therefore, {111}‐textured films are less susceptible to changes in properties due to mechanical constraints because there is overall less domain reorientation in {111} films than in {100} films. 相似文献