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1.
The pulse-stream technique, which represents neural states as sequences of pulses, is reviewed. Several general issues are raised, and generic methods appraised, for pulsed encoding, arithmetic, and intercommunication schemes. Two contrasting synapse designs are presented and compared. The first is based on a fully analog computational form in which the only digital component is the signaling mechanism itself-asynchronous, pulse-rate encoded digital voltage pulses. In this circuit, multiplication occurs in the voltage/current domain. The second design uses more conventional digital memory for weight storage, with synapse circuits based on pulse stretching. Integrated circuits implementing up to 15000 analog, fully programmable synaptic connections are described. A demonstrator project is described in which a small robot localization network is implemented using asynchronous, analog, pulse-stream devices. 相似文献
2.
The authors highlight several possible ways in which the construction industry could lower present emissions of the greenhouse gas, carbon dioxide. It is an excellent discussion document and is recommended reading. 相似文献
3.
Bond Gary R.; Dietzen Laura L.; McGrew John H.; Miller Larry D. 《Canadian Metallurgical Quarterly》1995,40(2):75
Tested the hypothesis that Ss with severe mental illnesses would achieve better vocational outcomes with an accelerated approach to supported employment (AASE), as compared to gradual approaches (GA) with prevocational training. 86 Ss (mean age 35.1 yrs) with a diagnosis of a serious mental illness, were randomly assigned to either the AASE, or the GA, which included a minimum of 4 mo prevocational training. Data were obtained on indicators of vocational outcomes over 2 yrs, and for a limited number of Ss (n=36), during the 4th yr of inception into the program. Initially, only 5% of Ss preferred prevocational training. After 1 yr, AASE Ss showed better outcomes for a range of indicators, including achievement of competitive employment, duration of employment and mean earnings. During the 4th yr, 59% of these Ss were competitively employed, as compared to only 6% of GA Ss. Rehabilitation is more effective using AASE than GA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Packaging engineers need to be able to accurately determine the forces present in the shipping environment in order to protect packaged goods. The purpose of this study was to determine the vertical vibration levels measured in three separate truck-trailer suspension systems; conventional leaf-spring, conventional air-ride and damaged air-ride. The main conclusion reached in this study is that the air-ride suspension when maintained gives lower power density (PD) levels on all road surfaces studied. A damaged air-ride suspension and leaf-spring suspension are very similar in response frequencies, although the damaged air-ride produces higher vibration levels at lower frequencies. 相似文献
5.
6.
A new method is presented to analyze reflection losses of integrated mirrors, taking into account the exact guided mode profile and assuming that this profile remains unchanged up to the reflecting plane. The fraction of the reflected light coupled to one of the guided modes of the output waveguide is calculated, taking into account the mirror reflection coefficient. The influence of both translation and tilt of the reflecting plane is investigated. The method applies for every guided mode and any reflection angles. Numerical calculations are derived for a 90° optical corner mirror 相似文献
7.
A mathematical model was developed to describe the removal of volatile organic compounds from drinking water in aeration basins. The model was used to simulate removal under a range of expected treatment conditions using the Continuous Systems Modeling Program. Results indicated that temperature and air-to-water ratio are the major factors influencing the removal of chloroform from water in an aeration basin. Bubble diameter was a lesser factor while liquid residence time had the smallest effect of the variables examined. 相似文献
8.
Morosi S. Marabissi D. Enrico Del Re Fantacci R. Del Santo N. 《Power Delivery, IEEE Transactions on》2006,21(4):1892-1897
This paper deals with a variable rate discrete multitone modulation system for broadband power-line communications, based on the bit-loading algorithm proposed by Leke and Cioffi. In the proposed system a suitable least mean square channel estimator is considered, which is based on the insertion of a training sequence (TS). The proposed approach will be compared with the ideal channel estimates, showing its effectiveness. Moreover, different TS lengths will be compared. The system performance, expressed in terms of bit rate and bit-error rate, is derived by simulation with and without estimation errors. The propagation environment has been assumed as a frequency-selective multipath fading channel with additive colored Gaussian noise, according to the in-building networks model. 相似文献
9.
M. Del C. Ruiz J. A. González J. B. Rivarola 《Metallurgical and Materials Transactions B》2004,35(3):439-448
The mechanism and kinetics of β-Ta2O5 chlorination, mixed with sucrose carbon, have been studied by a thermogravimetric technique. The investigated temperature
range was 500 °C to 850 °C. The reactants and reaction residues were analyzed by scanning electronic microscopy (SEM), X-ray
diffraction (XRD), and Brunauer-Emmett-Teller method for surface area (BET). The effect of various experimental parameters
was studied, such as carbon percentage, temperature, chlorine partial pressure, and flow, use of the multiple sample method,
and carbon previous oxidation. The carbon percentage and previous treatment have an effect on the system reactivity. The temperature
has a marked effect on the reaction rate. In the 500 °C to 600 °C temperature interval, the apparent activation energy is
144 kJ/mol of oxide, while at higher temperatures, the activation energy decreases. With high chorine partial pressures, the
order of reaction is near zero. The kinetic contractile plate model, X=kt, considering carbon oxidation as the controlling stage, is the one with the best fit to the experimental data. A probable
mechanism for the carbochlorination of β-Ta2O5 is proposed: (1) activation of chlorine on the carbon surface, (2) chlorination of Ta2O5, (3) oxidation of carbon, and (4) recrystallization of β-Ta2O5. 相似文献
10.
GaryFromer 《软件工程师》2003,(10):57-57
<正> 新的一年里,似乎每个人都在谈论中小企业日渐增长的软件需求,而且理由都很充分。今天的中小企业界定十分宽泛,从只有10个员工的公司到年收入5亿美金的企业都可以划归到这个范围里,他们现在可以找到很多专门为他们开发的解决方案,帮助他们改善生产效率、加强销售和合作机会,以及改善客户关系。但是在那些销售人员敲你的门,进来告诉你某个软件解决方案的好处之前,请你一定做好充分的准备。你的选择不仅仅关系到企业内部运营效率的提 相似文献