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991.
Gustavo Cerda-VillafañaYuriy S. Shmaliy 《Measurement》2011,44(4):730-737
In recent decades, there have been designed and developed passive surface acoustic wave radio frequency identification tags with time position encoding in groups of slots. For such tags identified when the received pulse-burst exceeds a threshold, we specify the generic identification (ID) error probability and optimize the threshold employing the Marcum Q-function of first order. As examples, we estimate the ID errors for the one-group 28-slot tag and Barker encoding. It is shown that, under the ideal conditions of equal SNRs (14.8 dB) in On-pulses and zeroth in Off-pulses, the ID error probability lesser 1% (one slip per 100 readings) can be guarantied with single reading for any reasonable number of slots. It becomes lesser 0.1% (1 slip per 1000 readings) with seven or lesser slots. 相似文献
992.
993.
Adam T. Martinsek 《Sequential Analysis》2013,32(2):169-177
The problem of constructing confidence bands with prescribed width and confidence for an unknown density function is considered. A two stage procedure, based on the confidence bands of Bickel and Rosenblatt (1973), is proposed and shown to achieve the desired goals.Moreover, the procedure is asymptotically efficient with respect to sample size. The possibility of using a fully sequential approach is exploredthe technical difficulties in this case are formidable, and perhaps insurmountable. 相似文献
994.
Christos K. Datsikas Kostas P. Peppas Fotis I. Lazarakis George S. Tombras 《AEUE-International Journal of Electronics and Communications》2010,64(11):1094-1099
In this paper we present analytical expressions for the lower bounds of the error performance of dual-hop amplify-and-forward transmissions over independent and not necessarily identical Generalized-K fading channels. Using a tight upper bound for the end-to-end SNR, a novel expression for the probability density function is derived. Based on the abovementioned formula, tight lower bounds for the average bit error probability for a variety of modulation schemes are derived. In order to validate the accuracy of the proposed mathematical analysis, various numerical and computer simulation results are presented. 相似文献
995.
In this paper, we propose a methodology which helps customers buy products through the Internet. This procedure takes into account the customer's level of desire in the product attributes, which are normally fuzzy, or in linguistically defined terms. The concept of fuzzy number will be used to measure the degree of similarities of the available products to that of the customer's requirements. The degrees of similarities so obtained over all the attributes give rise to the fuzzy probabilities and hence the fuzzy expected values of availing a product on the Internet as per the customer's requirement. Attribute‐wise the fuzzy expected values are compared with those of the available products on the Internet and the product that is closest to the customer's preference is selected as the best product. The multi‐attribute weighted average method is used here to evaluate and hence to select the best product. 相似文献
996.
997.
[Correction Notice: An erratum for this article was reported in Vol 13(2) of Psychological Methods (see record 2008-06808-007). In Figures 3B and 3D, the question marks (?) should read as multiplication signs (×). That is, it should read as β×λ?, β×λ?, and β×λ?? instead of β?λ?, β?λ?, and β?λ?? in Figure 3B and as γ×λ? and γ×λ? instead of γ?λ? and γ?λ? in Figure 3D.] In a recent article, A. Maydeu-Olivares and D. L. Coffman (2006; see record 2006-22258-002) presented a random intercept factor approach for modeling idiosyncratic response styles in questionnaire data and compared this approach with competing confirmatory factor analysis models. Among the competing models was the CT-C(M-1) model (M. Eid, 2000). In an application to the Life Orientation Test (M. F. Scheier & C. S. Carver, 1985), Maydeu-Olivares and Coffman found that results obtained from the CT-C(M-1) model were difficult to interpret. In particular, Maydeu-Olivares and Coffman challenged the asymmetry of the CT-C(M-1) model. In the present article, the authors show that the difficulties faced by Maydeu-Olivares and Coffman rest upon an improper interpretation of the meaning of the latent factors. The authors' aim is to clarify the meaning of the latent variables in the CT-C(M-1) model. The authors explain how to properly interpret the results from this model and introduce an alternative restricted model that is conceptually similar to the CT-C(M-1) model and nested within it. The fit of this model is invariant across different reference methods. Finally, the authors provide guidelines as to which model should be used in which research context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Ewald R. Weibel 《Journal of microscopy》1989,155(3):393-403
Obtaining, by means of microscopy, meaningful measurements pertaining to spatial structures requires methods which allow three-dimensional quantitative information to be derived from the reduced information available on the two-dimensional flat sections of the structure. The most powerful methods to that effect are those of stereology which are based on mathematical principles. This paper reviews the early invention of these methods, which sought to solve practical problems, and their further evolution as more rigorous mathematical foundations were developed. It is demonstrated that stereological methods are essentially sampling methods and that newer trends provide new and sound solutions to old and elusive problems, such as anisotropy or particle number and size. 相似文献
999.
Correctness criteria of some algorithms for uncertain reasoning using Incidence Calculus 总被引:4,自引:0,他引:4
Alan Bundy 《Journal of Automated Reasoning》1986,2(2):109-126
Incidence Calculus is a technique for associating uncertainty values with logical sentences. These uncertainty values are
called incidences and they are sets of points, which may be thought of as representing equivalence classes of situations,
Tarskian models, or possible worlds. Incidence Calculus was originally introduced in [1].
Incidence Calculus was designed to overcome various inherent problems with purely numeric mechanisms for uncertain reasoning
[2]. In particular, incidences can represent the dependence between sentences, which numbers cannot, and hence Incidence Calculus
can provide genuine, probabilistic reasoning.
In this paper we prove soundness and completeness results for some algorithms introduced in [1] and hence satisfy some of
the correctness criteria for Incidence Calculus. These algorithms can be used for probabilistic reasoning and to check the
consistency of the subjective probabilities of sentences. 相似文献
1000.