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991.
992.
Computer vision systems 总被引:1,自引:0,他引:1
993.
Tong Fang Mohsen A. Jafari Stephen C. Danforth Ahmad Safari 《Machine Vision and Applications》2003,15(2):63-75
This paper presents the concept of a process signature for the use of online signature analysis and defect detection in the layered manufacturing (LM) of ceramic sensors and actuators. To achieve the high quality of parts built by the fused deposition of ceramics (FDC), an online process-monitoring system is implemented to detect the processing defects. Using a process signature extracted from the image of a layer captured by the monitoring system, an ideal image is created that is then compared to the original image to detect and identify the defects. Some results of signature analysis and defect detection for single-material and multi-material parts are also presented.Received: 22 July 1999, Accepted: 21 October 2001, Published online: 29 October 2003
Correspondence to: Mohsen A. JafariThis work was supported by the Office of Naval Research under grant # N-0014-96-1-1175. Ref. US Patent # S-5738817, April 14, 1998. 相似文献
994.
995.
996.
Yun Zhang Xirong Huang Yuezhong Li 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1230-1235
BACKGROUND: [bmim][PF6] is a hydrophobic ionic liquid which could be considered as an environmentally friendly solvent for biocatalysis. In pure [bmim][PF6], however, alcohol dehydrogenase from yeast (YADH) has no catalytic activity. The aim of the present work was (1) to quantitatively study the negative effect of [bmim][PF6] on the catalytic activity of YADH and the related mechanism and (2) to made an attempt to lessen the negative effect of [bmim][PF6] on YADH by microemulsifying [bmim][PF6]. RESULTS: The activity of YADH in the homogeneous solution formed by H2O, CH3CH2OH and [bmim][PF6] decreased rapidly with the increase of the molar fraction of [bmim][PF6]. The inhibitory effect of [bmim][PF6] on YADH was probably caused by the competition of the imidazole group of [bmim][PF6] with the coenzyme NAD+ for the binding sites on YADH. In a water‐in‐[bmim][PF6] microemulsion, YADH was catalytically active due to the formation of the interfacial membrane of the nonionic surfactant TritonX‐100, which separated YADH from [bmim][PF6] and avoided the direct inactivation of [bmim][PF6] on YADH. Under optimal conditions, the activity of YADH was as high as 51 µmol L?1 min?1. CONCLUSION: [bmim][PF6] was an inhibitor of YADH and its negative effect on YADH could be lessened by its microemulsification. Copyright © 2008 Society of Chemical Industry 相似文献
997.
998.
e-Government systems differ from commercial information systems (IS) in that they frequently encompass strategic goals that go beyond efficiency, effectiveness and economy, and include political and social objectives such as trust in government, social inclusion, community regeneration, community well-being and sustainability. Designing e-Government systems that help to meet these objectives is a significant challenge for the future. This paper develops an evaluative design framework for e-Government projects that complements traditional approaches to IS evaluation. The framework is based upon Moor's concept of public value. It focuses upon citizens' and clients' experiences of service provision and service outcomes as contributors to the formation of public trust. Trust is shown to be related to the extent to which people feel that an e-Government service enhances their sense of being well-informed, gives them greater personal control, and provides them with a sense of influence or contingency. The framework's development and validation are founded upon analyses of a two live case studies in south-east England and London, U.K. 相似文献
999.
Ahmad Nozad Golikand Elaheh Lohrasbi Mohammad Ghannadi Maragheh Mehdi Asgari 《Journal of Applied Electrochemistry》2008,38(6):869-874
The effect of carbon surface oxidation on platinum supported carbon particles (Pt/C) with nitric acid was investigated by
cyclic voltammetry, electrochemical impedance spectroscopy, polarization experiments and chronoamperometry. Cyclic voltammograms,
polarization curves and electrochemical impedance spectra showed that the treated catalyst had much larger active surface
area and higher ionic conductivity than the untreated catalyst, and provided enhanced performance for oxygen reduction. The
formation of acidic groups was examined by IR spectra. The Pt/C surface oxidation had a large effect on the performance of
a gas diffusion electrode for oxygen reduction reaction. 相似文献
1000.
Benedetto Bozzini Bertrand Busson Claudio Mele Abderrahmane Tadjeddine 《Journal of Applied Electrochemistry》2008,38(7):897-906
We report on potential-dependent in situ SFG and DFG spectroscopy carried out at Au(111), Au(210), polycrystalline Au, Au–Cu
and Au–Ag–Cu electrodes in contact with aqueous solutions containing CN− and 4-cyanopyridine (4CP). Spectroelectrochemical work was complemented by cyclic voltammetry. The chief stress has been
placed on systematising and quantifying the interaction between 4CP and CN− and the attending effects on the vibrational and electronic structures of the interface. The voltammetric behaviour of the
investigated electrodes, modified by the addition of 4CP to the CN− electrolyte, denote changes in the CN− adsorption characteristics and effects of the adsorbed CN− layer on the electrodic reactivity of 4CP. The differences among the investigated electrodes can be explained in terms of
their respective degrees of atomic packing or with alloying effects on the stability of adsorbed CN−. The potential-dependent spectra have been analysed quantitatively with a model for the second order non linear susceptibility
accounting for vibrational and electronic effects. The spectral changes induced by addition of 4CP denote interaction of the
aromatic with the electrode through the CN− monolayer. The non-resonant contribution yields information on the effects of 4CP on the fine structure of the bound electron
density of states. 相似文献