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281.
We consider a group of several non-Bayesian agents that can fully coordinate their activities and share their past experience in order to obtain a joint goal in face of uncertainty. The reward obtained by each agent is a function of the environment state but not of the action taken by other agents in the group. The environment state (controlled by Nature) may change arbitrarily, and the reward function is initially unknown. Two basic feedback structures are considered. In one of them — the perfect monitoring case — the agents are able to observe the previous environment state as part of their feedback, while in the other — the imperfect monitoring case — all that is available to the agents are the rewards obtained. Both of these settings refer to partially observable processes, where the current environment state is unknown. Our study refers to the competitive ratio criterion. It is shown that, for the imperfect monitoring case, there exists an efficient stochastic policy that ensures that the competitive ratio is obtained for all agents at almost all stages with an arbitrarily high probability, where efficiency is measured in terms of rate of convergence. It is also shown that if the agents are restricted only to deterministic policies then such a policy does not exist, even in the perfect monitoring case. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
282.
Although the individualism–collectivism dimension is usually examined in a U.S. versus Asian context, there is variation within the United States. The authors created an eight-item index ranking states in terms of collectivist versus individualist tendencies. As predicted, collectivist tendencies were strongest in the Deep South, and individualist tendencies were strongest in the Mountain West and Great Plains. In Part 2, convergent validity for the index was obtained by showing that state collectivism scores predicted variation in individual attitudes, as measured by a national survey. In Part 3, the index was used to explore the relationship between individualism–collectivism and a variety of demographic, economic, cultural, and health-related variables. The index may be used to complement traditional measures of collectivism and individualism and may be of use to scholars seeking a construct to account for unique U.S. regional variation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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284.
A Smart Sensor System for Carbon Monoxide Detection   总被引:1,自引:0,他引:1  
This paper illustrates a smart sensor system for carbonmonoxide detection. An innovative technological approach hasbeen pursued to fabricate gas sensors on silicon substrate, compatiblewith IC fabrication. A mixed analog-digital electronic interfaceprocesses the outputs of three sensors to compensate relativehumidity and interfering gases. Sigma-delta signal processingand low-frequency noise reduction techniques are used to minimizesilicon area and to meet the required performance in a standardCMOS technology.  相似文献   
285.
A communication system with nonlinear Power Amplifier (PA) is considered. The PA nonlinearity forces the designer of communication system to choose proper Back-Off, which influences three major parameters of the communication system: (i) power efficiency, (ii) Adjacent Channel Power Ratio (ACPR), and (iii) bit rate expressed by Mutual Information (MI). Having these three parameters, we propose to evaluate the performance of a communication system with nonlinear PA using the fact that ACPR is dictated by the regulator/communication standard. In what follows we propose to find power efficiency and MI as a function of ACPR. To illustrate the usefulness of the proposed method, the Solid State Power Amplifier (SSPA), and two linearized versions of SSPA are considered. The first version is a perfectly linearized PA using pre-distortion resulting with Soft Envelope Limiter (SEL), and the second is the Feed-Forward (FF) architecture based on SSPA. For each of the PAs ACPR, power efficiency and MI are found. While the analysis of SSPA and SEL is mainly based on the existing literature, the analysis of FF may be considered as a new contribution. From the results of the analysis it is concluded that linearization improves the overall performance of communication system. It is also shown that the pre-distortion method (SEL) shows better performance than FF.  相似文献   
286.
Roasted macadamia (Macadamia integrifolia Storey) nuts were salted at various levels up to 19 g kg?1 and presented to a taste panel. The results showed that the assessors could be divided into 'salt dislikers', to whom perceived quality decreased linearly with increase in salt content, and 'salt likers', to whom perceived quality increased as the salt content increased. It follows that the nuts can be produced to suit these two market segments separately, or else a single lightly salted compromise product can be offered to both groups.  相似文献   
287.
Kinetic study on the hexacelsian-celsian phase transformation   总被引:2,自引:0,他引:2  
The hexacelsian-celsian transformation from grains of 1/4 in. (0.635 cm) size is slow and erratic. This is because the rate of heterogeneous nucleation in such grains is low and is influenced by contamination present in the furnace. When the grain size is reduced to a –200 mesh powder, heterogeneous nucleation becomes a dominant factor and the transformation is accelerated. The transformation has three stages: the first is controlled by the rate of crystal growth, the second is controlled by the rates of nucleation and crystal growth, and the third is controlled by the rate of nucleation.The activation energy of crystal growth in the first stage of transformation is 20.1 kcal mole–1 ±20%. This suggests that the hexacelsian-celsian transformation does not involve Si-0 and Al-O bond openings, since this would be expected to involve an activation energy of at least 60 kcal mole–1.  相似文献   
288.
289.
The idea of discrete constrained notch filters is well known and widely described in the literature. Time-invariant as well as time-varying filters are considered. Because of the discrete nature of such filters, their application is limited to sampled signals, usually obtained as samples of low-frequency signals. the aim of this paper is to give some ideas on how to synthesize a time-varying analogue constrained notch filter which can be used directly for continuous signals.  相似文献   
290.
We review the status of European publishing in high-impact Information System (IS) journals finding that the European publication record is disappointing. We consider popular explanations to this state of affairs and find them neither credible nor useful for improving the European record. We propose several constructive reasons for this including (1) the lack of appreciation of the article genre, (2) weak publishing cultures, (3) inadequate Ph.D. preparation for article publishing, (4) weak reviewing practices, (5) poorer command of research methods, (6) poorer understanding of the reviewing protocols, and (7) institutional shaping of research funding in Europe. We formulate several recommendations to affect these causes at the individual, institutional, journal, and European community level.  相似文献   
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