A unified approach to characterization of PWM and quasi-PWM switching converters: topological constraints, classification, and synthesis

1991 ◽  
Vol 6 (4) ◽  
pp. 719-726 ◽  
Author(s):  
A.K.S. Bhat ◽  
F.D. Tan
Keyword(s):  
Switching Converters ◽  
Unified Approach ◽  
Topological Constraints

Improved detection of motifs with preferential location in promoters

Genome ◽  
2010 ◽  
Vol 53 (9) ◽  
pp. 739-752 ◽  
Author(s):  
Virginie Bernard ◽  
Alain Lecharny ◽  
Véronique Brunaud
Keyword(s):  
In Silico ◽  
Gene Expression Regulation ◽  
Window Size ◽  
Sliding Window ◽  
In Silico Prediction ◽  
Distribution Profile ◽  
Topological Constraints ◽  
Automatic Adaptation ◽  
Preferential Location

Many transcription factor binding sites (TFBSs) involved in gene expression regulation are preferentially located relative to the transcription start site. This property is exploited in in silico prediction approaches, one of which involves studying the local overrepresentation of motifs using a sliding window to scan promoters with considerable accuracy. Nevertheless, the consequences of the choice of the sliding window size have never before been analysed. We propose an automatic adaptation of this size to each motif distribution profile. This approach allows a better characterization of the topological constraints of the motifs and the lists of genes containing them. Moreover, our approach allowed us to highlight a nonconstant frequency of occurrence of spurious motifs that could be counter-selected close to their functional area. Therefore, to improve the accuracy of in silico prediction of TFBSs and the sensitivity of the promoter cartography, we propose, in addition to automatic adaptation of window size, consideration of the nonconstant frequency of motifs in promoters.

Recent results on characterization of probability distributions: a unified approach through extensions of Deny&s theorem

1986 ◽  
Vol 18 (03) ◽  
pp. 660-678 ◽  
Author(s):  
C. Radhakrishna Rao ◽  
D. N. Shanbhag
Keyword(s):  
Negative Binomial ◽  
Short Proof ◽  
Probability Distributions ◽  
Direct Link ◽  
Unified Approach ◽  
Binomial Distributions ◽  
Characterization Of Probability Distributions ◽  
Special Cases ◽  
Convolution Equations

The problem of identifying solutions of general convolution equations relative to a group has been studied in two classical papers by Choquet and Deny (1960) and Deny (1961). Recently, Lau and Rao (1982) have considered the analogous problem relative to a certain semigroup of the real line, which extends the results of Marsaglia and Tubilla (1975) and a lemma of Shanbhag (1977). The extended versions of Deny&s theorem contained in the papers by Lau and Rao, and Shanbhag (which we refer to as LRS theorems) yield as special cases improved versions of several characterizations of exponential, Weibull, stable, Pareto, geometric, Poisson and negative binomial distributions obtained by various authors during the last few years. In this paper we review some of the recent contributions to characterization of probability distributions (whose authors do not seem to be aware of LRS theorems or special cases existing earlier) and show how improved versions of these results follow as immediate corollaries to LRS theorems. We also give a short proof of Lau–Rao theorem based on Deny&s theorem and thus establish a direct link between the results of Deny (1961) and those of Lau and Rao (1982). A variant of Lau–Rao theorem is proved and applied to some characterization problems.

scholarly journals Characterization of sets of limit measures of a cellular automaton iterated on a random configuration

2016 ◽  
Vol 38 (2) ◽  
pp. 601-650
Author(s):  
BENJAMIN HELLOUIN DE MENIBUS ◽  
MATHIEU SABLIK
Keyword(s):  
Cellular Automaton ◽  
Additional Hypothesis ◽  
Topological Constraints ◽  
Mean Convergence ◽  
Similar Characterization ◽  
Limit Points ◽  
Limit Probability ◽  
Initial Measure ◽  
Random Configuration

The asymptotic behaviour of a cellular automaton iterated on a random configuration is well described by its limit probability measure(s). In this paper, we characterize measures and sets of measures that can be reached as limit points after iterating a cellular automaton on a simple initial measure. In addition to classical topological constraints, we exhibit necessary computational obstructions. With an additional hypothesis of connectivity, we show these computability conditions are sufficient by constructing a cellular automaton realizing these sets, using auxiliary states in order to perform computations. Adapting this construction, we obtain a similar characterization for the Cesàro mean convergence, a Rice theorem on the sets of limit points, and we are able to perform computation on the set of measures, i.e. the cellular automaton converges towards a set of limit points that depends on the initial measure. Last, under non-surjective hypotheses, it is possible to remove auxiliary states from the construction.

scholarly journals Homotopy of compact symmetric spaces

1992 ◽  
Vol 34 (2) ◽  
pp. 221-228 ◽  
Author(s):  
John M. Burns
Keyword(s):  
Symmetric Spaces ◽  
Unified Approach ◽  
Topological Characterization ◽  
New Approach ◽  
Totally Geodesic ◽  
Compact Symmetric Space ◽  
Geodesic Submanifolds ◽  
Totally Geodesic Submanifolds ◽  
Compact Symmetric Spaces

In recent years a new approach to the study of compact symmetric spaces has been taken by Nagano and Chen [10]. This approach assigned to each pair of antipodal points on a closed geodesic a pair of totally geodesic submanifolds. In this paper we will show how these totally geodesic submanifolds can be used in conjunction with a theorem of Bott to compute homotopy in compact symmetric spaces. Some of the results are already known (see [1], [5], [11] for example) but we include them here for completeness and to illustrate this unified approach. We also exhibit a connection between the second homotopy group of a compact symmetric space and the multiplicity of the highest root. Using this in conjunction with a theorem of J. H. Cheng [6] we obtain a topological characterization of quaternionic symmetric spaces with antiquaternionic involutive isometry. The author would like to thank Prof T. Nagano for all his help and his detailed descriptions of the totally geodesic submanifolds mentioned above.

A NEW UNIFIED SOLIDS FLUX-BASED APPROACH FOR THE DESIGN OF FINAL CLARIFIERS: DESCRIPTION AND COMPARISON WITH TRADITIONAL CRITERIA

1994 ◽  
Vol 30 (4) ◽  
pp. 57-66 ◽  
Author(s):  
M. von Sperling
Keyword(s):  
Activated Sludge ◽  
Unified Approach ◽  
Traditional Design

The paper presents a methodology for the derivation of the overflow rate and the solids flux for the design of final sedimentation tanks in activated sludge plants. The method is based on a simplified characterization of the sludge into three ranges, according to its settleability (good, fair or poor). The coefficients were derived from the integration of well known results obtained by different authors, which have to-date been used only individually. This unified approach widens the breadth of the previous studies, allowing a more reliable detennination of the design rates. The rates obtained with the proposed method were compared with the values suggested by traditional design manuals, with both approaches leading to similar results.

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