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261.
Tom McCann 《Microprocessors and Microsystems》1981,5(2):65-68
In-circuit emulation is the ability to imitate electrically a target microprocessor, responding to system inputs or instructions, and producing accurately the expected outputs or responses to the instructions. A modular building block approach to microprocessor-based design is given, the Slave Emulator Control Unit (SECU) is described and its flexibility shown. 相似文献
262.
Gelinck GH Huitema HE van Veenendaal E Cantatore E Schrijnemakers L van der Putten JB Geuns TC Beenhakkers M Giesbers JB Huisman BH Meijer EJ Benito EM Touwslager FJ Marsman AW van Rens BJ de Leeuw DM 《Nature materials》2004,3(2):106-110
At present, flexible displays are an important focus of research. Further development of large, flexible displays requires a cost-effective manufacturing process for the active-matrix backplane, which contains one transistor per pixel. One way to further reduce costs is to integrate (part of) the display drive circuitry, such as row shift registers, directly on the display substrate. Here, we demonstrate flexible active-matrix monochrome electrophoretic displays based on solution-processed organic transistors on 25-microm-thick polyimide substrates. The displays can be bent to a radius of 1 cm without significant loss in performance. Using the same process flow we prepared row shift registers. With 1,888 transistors, these are the largest organic integrated circuits reported to date. More importantly, the operating frequency of 5 kHz is sufficiently high to allow integration with the display operating at video speed. This work therefore represents a major step towards 'system-on-plastic'. 相似文献
263.
Heskes T 《Neural computation》2004,16(11):2379-2413
We derive sufficient conditions for the uniqueness of loopy belief propagation fixed points. These conditions depend on both the structure of the graph and the strength of the potentials and naturally extend those for convexity of the Bethe free energy. We compare them with (a strengthened version of) conditions derived elsewhere for pairwise potentials. We discuss possible implications for convergent algorithms, as well as for other approximate free energies. 相似文献
264.
Tom?GrossEmail author Wolfgang?Prinz 《Computer Supported Cooperative Work (CSCW)》2004,13(3-4):283-303
Users who work together require adequate information about their cooperative environment: about other group members presence and activities, about shared artefacts, etc. In the CSCW literature several concepts, prototypes, and systems for providing this group awareness information have been presented. In general, they capture information from the environment, process it, and present it to the users. This paper addresses the processing aspect; in particular, we present a concept for processing awareness information by means of awareness contexts. With this concept we address the problem of contextualising event notifications enabling the presentation of notifications in the appropriate user situation. We describe a lightweight model and its integration into an event and notification infrastructure. We report on an empirical study, and draw some conclusions for the design of context-awareness for cooperative environments. 相似文献
265.
Evaluation of the impact of fuel hydrocarbons and oxygenates on groundwater resources 总被引:2,自引:0,他引:2
The environmental behavior of fuel oxygenates (other than methyl tert-butyl ether [MTBE]) is poorly understood because few data have been systematically collected and analyzed. This study evaluated the potential for groundwater resource contamination by fuel hydrocarbons (FHCs) and oxygenates (e.g., tert-butyl alcohol [TBA], tertamyl methyl ether [TAME], diisopropyl ether [DIPE], ethyl tert-butyl ether [ETBE], and MTBE) by examining their occurrence, distribution, and spatial extent in groundwater beneath leaking underground fuel tank (LUFT) facilities, focusing on data collected from over 7200 monitoring wells in 868 LUFT sites from the greater Los Angeles, CA, region. Excluding the composite measure total petroleum hydrocarbons as gasoline (TPHG), TBA has the greatestsite maximum (geometric mean) groundwater concentration among the study analytes; therefore, its presence needs to be confirmed at LUFT sites so that specific cleanup strategies can be developed. The alternative ether oxygenates (DIPE, TAME, and ETBE) are less likely to be detected in groundwater beneath LUFT facilities in the area of California studied and when detected are present at lower dissolved concentrations than MTBE, benzene, or TBA. Groundwater plume length was used as an initial indicator of the threat of contamination to drinking water resources. Approximately 500 LUFT sites were randomly selected and analyzed. The results demonstrate MTBE to pose the greatest problem, followed by TBA and benzene. The alternative ether oxygenates were relatively localized and indicated lesser potential for groundwater resource contamination. However, all indications suggest the alternative ether oxygenates would pose groundwater contamination threats similar to MTBE if their scale of usage is expanded. Plume length data suggest that in the absence of a completely new design and construction of the underground storage tank (UST) system, an effective management strategy may involve placing greater emphasis on UST program for ensuring adequate enforcement and compliance with existing UST regulations. 相似文献
266.
Jaward FM Farrar NJ Harner T Sweetman AJ Jones KC 《Environmental science & technology》2004,38(1):34-41
This study presents concurrently sampled ambient air data for a range of persistent organic pollutants at the continental scale. This was achieved using a passive air sampling system, deploying polyurethane foam disks, which was prepared in one laboratory, sealed to prevent contamination, sent out by courier to volunteers participating in different countries, exposed for 6 weeks, collected, resealed, and returned to the laboratory for analysis. Europe was the study area--a region with a history of extensive POPs usage and emission and with marked national differences in population density, the degree of urbanization and industrial/agricultural development. Samplers were deployed at remote/rural/urban locations in 22 countries and analyzed for PCBs, a range of organochlorine pesticides (HCB, alpha-HCH, gamma-HCH, ppDDT, ppDDE), and PBDEs. Calculated air concentrations were in line with those obtained by conventional active air sampling techniques. The geographical pattern of all compounds reflected suspected regional emission patterns and highlighted localized hotspots. PCB and PBDE levels varied by over 2 orders of magnitude; the highest values were detected in areas of high usage and were linked to urbanized areas. HCB was relatively uniformly distributed, reflecting its persistence and high degree of mixing in air. Higher gamma-HCH, ppDDT, and ppDDE levels generally occurred in South and East Europe. 相似文献
267.
A volumetric optical disk that has multiple transparent films with optical switching layers is used as a recording medium to increase the number of recording layers. In the disk the optical switching layer is adapted to reduce decay of laser energy and increase reading and recording sensitivity. Well-defined marks of approximately 100-nm depth can be placed precisely on the transparent films by a focused laser beam. Writing and reading of a four-layer recordable disk, fabricated by molding and spin bonding, have been demonstrated experimentally. The volumetric disk can achieve a high recording capacity with conventional optical pickups. 相似文献
268.
We present the methodological background, the range of applicability, and the on-line usage of two software packages, MIESCHKA and CYL, which we have developed for light-scattering analysis on nonspherical particles. MIESCHKA solves Maxwell's equations in a rigorous way but is restricted to axisymmetric geometries, whereas CYL is an approximation for finite columns with nonspherical cross sections. We have established an easy on-line access to both of these programs through the Virtual Laboratory. Its generic software infrastructure was designed to simplify the web-based usage and to support the intercomparability of scientific software. 相似文献
269.
The MITOM code was developed at UAB (Universitat Autònoma de Barcelona) for unfolding neutron spectrometric measurements with a Bonner spheres system (BSS). One of the main characteristics of this code is that an initial parameterisation of the neutron energy components (thermal, intermediate and fast) is needed. This code uses the Monte Carlo method and the Bayesian theorem to obtain a set of solutions achieving different criteria and conditions between calculated and measured count rates. The final solution is an average of the acceptable solutions. The MITOM code was tested for ISO sources and a good agreement was observed between the reference values and the unfolded ones for global magnitudes. The code was applied recently to characterise both thermal SIGMA and CANEL/T400 sources of the IRSN facilities. The results of these applications were very satisfactory as well. 相似文献
270.
Wright Thomas L.; Holman Tom; Steele William G.; Silverstein Gail 《Canadian Metallurgical Quarterly》1980,38(6):1005
145 males (mean age 21.9 yrs) enrolled in an incentive-based reformatory were administered Rotter's Internal–External Locus of Control (LOC) Scale, Marlowe–Crowne Social Desirability Scale, and several measures of expectancy/importance of success and failure. After success or failure at mastery attempts, Ss made causal attributions derived from both J. B. Rotter's (1966) and B. Weiner's (1972) theories. Results show that internal LOC inmates, relative to externals, demonstrated greater mastery and attributed more responsibility to themselves for success, even with social desirability controlled. Defensive externality hypotheses involving both major moderators of LOC, interpersonal trust and action taking, as well as 4 proposed aspects of defensive externality were not supported. Contrary to predictions, trust-defensive externals made more internal nondefensive attributions after failure than trust-congruent externals did. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献