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e-Manufacturing:Characteristics,applications and potentials

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Progress in Natural Science:Materials International 2008年第11期18卷 1323-1328页

作者： richard j.Bateman Advanced Manufacturing & Enterprise Engineering(AMEE) School of Engineering and DesignBrunel UniversityUxbridgeMiddlesex UB8 3PHUK

In this paper,an engineering oriented approach is proposed towards e-manufacturing and its *** characteristics and potential of e-manufacturing are presented with a number of application examples developed by the authors’ research *** advances in e-manufacturing and applications are also highlighted and critically *** paper concludes with a further discussion on the promises and impact of e-manufacturing technology and philosophy on modern manufacturing industry and the practices.

关键词： e-manufacturing e-design Global manufacturing Agile manufacturing Digital manufacturing

A perceptual quality metric for 3D triangle meshes based on spatial pooling

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Frontiers of Computer Science 2018年第4期12卷 798-812页

作者： Xiang FENG Wanggen WAN richard Yi Da XU Haoyu CHEN Pengfei LI j. Alfredo SANCHEZ School of Communication and Information Engineering Shanghai University Shanghai 200444 China Faculty of Engineering and Information Technology University of Technology Sydney Sydney NSW 2007 Australia Institute of Smart City Shanghai University Shanghai 200444 China Department of Computing Electronics and Mechatronics Universidad de las Americas Puebla (UDLAP) Cholula 72820 Mexico

In computer graphics, various processing operations are applied to 3D triangle meshes and these processes often involve distortions, which affect the visual quality of surface geometry. In this context, perceptual quality assessment of 3D triangle meshes has become a crucial issue. In this paper, we propose a new obj.ctive quality metric for assessing the visual difference between a reference mesh and a corresponding distorted mesh. Our analysis indicates that the overall quality of a distorted mesh is sensitive to the distortion distribution. The proposed metric is based on a spatial pooling strategy and statistical descriptors of the dis- tortion distribution. We generate a perceptual distortion map for vertices in the reference mesh while taking into account the visual masking effect of the human visual system. The proposed metric extracts statistical descriptors from the dis- tortion map as the feature vector to represent the overall mesh quality. With the feature vector as input, we adopt a support vector regression model to predict the mesh quality score. We validate the performance of our method with three publicly available databases, and the comparison with state-of-the-art metrics demonstrates the superiority of our method. Experimental results show that our proposed method achieves a high correlation between obj.ctive assessment and subj.ctive scores.

关键词： mesh visual quality assessment spatial pooling statistical descriptors support vector regression visual masking

Gold modified cobalt-based Fischer-Tropsch catalysts for conversion of synthesis gas to liquid fuels

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 262-269页

作者： Alan j. Mccue j.ra Aponaviciute richard P.K. Wells j.mes A. Anderson Surface Chemistry and Catalysis Group Department of Chemistry University of Aberdeen AB24 3UE Abcrdccn UK Surface Chemistry and Catalysis Group School of Engineering University of Aberdeen AB24 3UE Aberdeen UK

The addition of Au as a promoter/modifier for alumina supported Co catalyst has been studied by combined in-situ high temperature, high pressure Fourier transform infrared （FTIR） and on-line gas chromatography. The combination of these tools permitted the state of the active catalyst surface to be monitored while following the elution of reaction products during the first 5-7 h on stream of the catalyst. The catalysts under study were a 10%Co/ A1203 and a 2.5%Au/10%Co/A1203. Samples were characterised before use using Raman and temperature programmed reduction （TPR）. During the initial stages of reaction, hydrocarbons were built up on the surface of the catalyst as monitored by FTIR and the nature and amount of these species were assessed in terms of CH2/CH3 ratio and the density of these alkyl fragments by employing absorption coefficients for the individual components. The nature and reducibility of the Co particles were modified by the presence of Au while the later also shifted the CO/ H2 balance by acting as an effective water-gas shift catalyst during the early stages of reaction. This characteristic was lost during reaction as a consequence of redistribution of the two metallic phases.

关键词： gold modified catalyst conversion of synthesis gas

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New Development in Study of the Faustmann Optimal Forest Harvesting

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Chinese j.urnal of Population,Resources and Environment 2010年第3期8卷 38-43页

作者： Wang Feng Xu j.nhong richard j. Brazee Economics and Management School of Northwest University Xi＇an Shaanxi 710069 China Department of Natural Resources and Environmental Sciences in University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Chinese forest resources have become very scarce in the face of rapid economic growth demand, while the reform of collective forest right system is in full swing across the country. It will directly affect the regeneration level of forest resources and the diverse ecological value functions. In this article, the mainstream model paradigm of forest economics, that is, the basic framework of the Faustmann model and its evolution process are made in a more detailed explanation, especially the extended model including considered silvicultural effort, tax subsidies, risk dynamic management, and forest regeneration factors are made in more detailed explanations. This article concludes with the future further research directions of forest economics, including the design of dynamic models that includes considered uneven-aged forest management, non-timber goods and services, dynamic forest models. The research reflects the general trend of interdisciplinary and cross-border.

关键词： forest resources forest optimal harvesting Faustmann model dynamic forest models

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Formation of CoAl layered double hydroxide on the boehmite surface and its role in tungstate sorption

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j.urnal of Environmental Sciences 2018年第3期30卷 103-115页

作者： Hyuck Hur richard j.Reeder Department of Chemistry Stony Brook University Stony Brook NY 11794 USA Department of Geosciences Stony Brook University Stony Brook NY 11794 USA

Sorption of tungstate on boehmite（γ-Al OOH）is increased by co-sorption with Co^（2＋）over the near-neutral p H *** uptake experiments show up to a 3-fold increase in tungstate uptake over the range WO4^（2-）=50–1000μmol/L compared to boehmite not treated with Co^（2＋）.Desorption experiments reveal a corresponding decrease in sorption reversibility for tungstate co-sorbed with Co^（2＋）.Reaction of boehmite with Co^（2＋）results in the formation of Co Al layered double hydroxide（LDH）,as confirmed by X-ray diffraction and X-ray absorption *** L3-edge X-ray absorption near edge structure（XANES）reveals that W（VI）is octahedrally coordinated in all sorption samples,with polymeric tungstate species forming at higher tungstate concentrations.X-ray diffraction and X-ray absorption spectroscopy indicate that the mechanism for enhancement of tungstate uptake is the formation of surface complexes on boehmite at low tungstate concentrations,while exchange into the Co Al LDH becomes important at higher tungstate *** results provide a basis for developing strategies to enhance tungstate sorption and to limit its environmental mobility at near-neutral pH conditions.

关键词： Tungsten Tungstate Cobalt Boehmite (AIOOH) Layered double hydroxide Adsorption

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Emerging therapeutic options for the management of hepatitis C infection

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World j.urnal of Gastroenterology 2014年第23期20卷 7079-7088页

作者： j.richard Thompson Department of Pharmacy Practice One University Park DriveLipscomb University College of PharmacyNashvilleTN 37204United States

Until recently the traditional treatment for hepatitis C infection included pegylated interferon and ribavirin combination *** sustained virological response(SVR)seen with this combination is poor and requires lengthy treatment to ***,significant side effects and numerous contraindications prevented many patients from being successfully treated with this *** 2011,two new protease inhibitors,telaprevir and boceprevir,were approved for use with pegylated interferon and ribavirin in the United States by the United States Food and Drug *** agents have significantly improved SVR rates;however significant problems with toxicity remain including severe skin rash and *** are a wide range of compounds in late stage development for the future treatment of hepatitis C that exploit many different mechanisms of viral *** of these compounds include additional protease inhibitors,like telaprevir and boceprevir,as well as inhibitors of other nonstructural proteins in the viral genome such as NS5A and NS5B,and compounds that target host proteins within the *** of these agents are being developed for oral administration once daily and various combinations are being assessed for use without the need for pegylated interferon and *** paper reviews agents in late phase development that may be commercially available within 1-2 years.

关键词： Hepatitis C Pharmacotherapy Interferon Ribavirin Protease inhibitors Polymerase inhibitors Cyclophilin inhibitors

Acid stress response in environmental and clinical strains of enteric bacteria

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Frontiers in Biology 2012年第6期7卷 495-505页

作者： Gabriel j. SWENSON j. STOCHASTIC Franklyn F. BOLANDER, j.. richard A. LONG Biological Sciences University of South Carolina Columbia SC 29208 USA Marine Science Program University of South Carolina Columbia SC 29208 USA Biology Department Paine College Augusta GA 30901 USA

The success of many enteric bacteria is hinged on the ability to tolerate environmental stress such as extreme acidity. The acid stress response （ASR） has been investigated in many enteric bacteria and has been shown to involve variable expression of a broad spectrum of genes involved in transcriptional regulation, metabolism, colonization and virulence; representing a linkage between acid tolerance and pathogenicity. Though the maj.rity of ASR studies have been conducted in laboratory conditions and from the perspective of pathogenicity, the role of environmental reservoirs on acid adaptation has recently emerged as an important aspect of pathogenic microbial ecology. This mini-review profiles ASR in three opportunistic enteric pathogens and synthesizes recent work pertaining to the study of this dynamic response.

关键词： acid stress response enteric bacteria microbial ecology transcriptional regulation virulence

Mitotic Spindle Organization by the Preprophase Band

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Molecular Plant 2008年第6期1卷 950-960页

作者： j. Christian Ambrose richard Cyr The Pennsylvania State University Department of Biology The Huck Institutes of the Life Sciences Integrative Biosciences Graduate Degree Program PlantPhysiology Program University Park PA 16802 USA Present address: Department of Botany University of British Columbia Vancouver British Columbia V6T 1Z4 Canada

In higher plants, the preprophase band （PPB） of microtubules （MTs） forecasts the cell division site prior to mitosis and specifies the organization of MTs into a bipolar prophase spindle surrounding the nucleus. However, the mechanisms governing this PPB-dependent establishment of bipolarity are unclear. Here, we present evidence from live cell imaging studies that suggest a role for the MTs bridging the PPB and the prophase nucleus in mediating this function. Results from drug treatments, along with genetic evidence from null kinesin plants, suggest that these MTs contribute to the bipolarity, orientation, and position of the prophase spindle. Specifically, the absence of these bridge MTs is associated with lack of bipolarity, while non-uniform distributions of bridge MTs correlate with prophase spindle migration, deformation, and enhanced bipolarity toward the region of highest bridge MT density. This behavior does not require actomyosin-based forces, and is enhanced by suppressing MT dynamics with taxol. These observations occur during late prophase, and are coincident with the gradual closing of annular spindle poles. Based on these data, we describe a hypothetical mechanism for bridge MT-dependent organization of prophase spindles.

关键词： preprophase band mitosis acentrosomal spindle microtubule kinesin ATK5 cytokinesis.

Stereochenlical effects on functional selectivity at the dopamine D2L receptor

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Stereochenlical effects on functional selectivity at the dop...