Local Algorithms for Estimating Effective Resistance

This article analyses the aesthetics of silent political resistance by focusing on refugees’ silent political action. The starting point for the analysis is Jacques Rancière’s philosophy and his theorisation of the aesthetics of politics. The article enquires into the aesthetic meaning of silent refugee activism and interprets how refugees’ silent acts of resistance can constitute aesthetically effective resistance to what can be called the ‘speech system’ of statist, representative democracy. The article analyses silence as a political tactic and interprets the emancipatory meaning of silent politics for refugees. It argues that refugees’ silent acts of political resistance can powerfully affect aesthetic, political subversion in prevailing legal-political contexts.

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Seed production of barnyardgrass (Echinochloa crus-galli) in response to time of emergence in cotton and rice

The Journal of Agricultural Science ◽

10.1017/s0021859611000876 ◽

2011 ◽

Vol 150 (6) ◽

pp. 717-724 ◽

Cited By ~ 16

Author(s):

M. V. BAGAVATHIANNAN ◽

J. K. NORSWORTHY ◽

K. L. SMITH ◽

P. NEVE

Keyword(s):

United States ◽

Seed Production ◽

Herbicide Resistance ◽

Crop Production ◽

Integrated Management ◽

Resistance Management ◽

Simulation Models ◽

Effective Resistance ◽

Southern United States

SUMMARYThe spread of herbicide resistance in barnyardgrass (Echinochloa crus-galli(L.) Beauv.) poses a serious threat to crop production in the southern United States. A thorough knowledge of the biology of barnyardgrass is fundamental for designing effective resistance-management programmes. In the present study, seed production of barnyardgrass in response to time of emergence was investigated in cotton and rice, respectively, in Fayetteville and Rohwer, Arkansas, over a 2-year period (2008–09). Barnyardgrass seed production was greater when seedlings emerged with the crop, but some seed production was observed even if seedlings emerged several weeks after crop emergence. Moreover, barnyardgrass seed production was highly variable across environments. When emerging with the crop (0 weeks after crop emergence (WAE)), barnyardgrass producedc. 35 500 and 16 500 seeds/plant in cotton, andc. 39 000 and 2900 seeds/plant in rice, in 2008 and 2009, respectively. Seed production was observed when seedlings emerged up to 5 WAE (2008) or 7 WAE (2009) in cotton and up to 5 WAE (2008, 2009) in rice; corresponding seed production wasc. 2500 and 1500 seeds/plant in cotton, andc. 14 700 and 110 seeds/plant in rice, in 2008 and 2009, respectively. The results suggest that cultural approaches that delay the emergence of barnyardgrass or approaches that make the associated crop more competitive will be useful in integrated management programmes. In the context of herbicide resistance management, it may be valuable to prevent seed return to the seedbank, irrespective of cohorts. The findings are vital for parameterizing herbicide resistance simulation models for barnyardgrass.

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Structural learning of Bayesian networks using local algorithms based on the space of orderings

Soft Computing ◽

10.1007/s00500-010-0623-x ◽

2010 ◽

Vol 15 (10) ◽

pp. 1881-1895 ◽

Cited By ~ 7

Author(s):

Juan I. Alonso-Barba ◽

Luis delaOssa ◽

Jose M. Puerta

Keyword(s):

Bayesian Networks ◽

Structural Learning ◽

Local Algorithms

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Specific Susceptibility to HCN and the amount of HCN recovered from Fumigated Insects

Bulletin of Entomological Research ◽

10.1017/s0007485300025414 ◽

1951 ◽

Vol 42 (2) ◽

pp. 399-418 ◽

Cited By ~ 7

Author(s):

S. Pradhan ◽

S. C. Bhatia

Keyword(s):

Body Weight ◽

Water Content ◽

Relative Position ◽

Surface Resistance ◽

Internal Resistance ◽

Effective Resistance ◽

The Body ◽

Effective Dosage ◽

Adult Females ◽

The Dead

The relationship was studied between susceptibility of a number of different species of insects to HCN fumigation and the recovery of HCN from them immediately after fumigation.The test insects used were Tribolium castaneum, seventh stage caterpillars of Corcyra cephalonica, first-and second-instar nymphs of Drosicha sp., third-and fourthinstar nymphs of Drosicha sp. and adult females of Drosicha sp.The apparatus and methods used in the fumigation and in the recovery of HCN from the fumigated insects are fully described.Preliminary expsriments showed that the processes of distillation and redistillation did not affect the recovery of HCN but that the result obtained for recovery from distillation could be affected if some volatile reducing substance were produced and carried over to the distillate. It was found that this did actually take place in the case of one of the test insects—T. castaneum—but that redistillation got rid of the impurity.In the main experiments it was shown that, on the assumption that the concentration of HCN to which insects are exposed is the effective dosage, the susceptibility of the test insects varied in the following descending order : firstand second-stage nymphs of Drosicha sp. > third- and fourth-stage nymphs of Drosicha sp.>C. cephalonica> T. castaneum>the adult females of Drosicha sp.When the same insects were arranged in descending order of the quantities of HCN recovered per 100 gm. of body weight, the order was identical except for the nymphs of Drosicha sp. which occupied a different relative position. The two categories of nymphs of Drosicha sp. were found to occupy a different relative position again with regard to the other three test insects when exposed to a superlethal concentration and assessed for recovery of HCN per 100 gr. body weight.Parallel batches of T. castaneum and C. cephalonica were fumigated and the HCN was recovered from the dead and survivors. More HCN was recovered from the dead insects than from those that survived.Both recovery and sorption of HCN were estimated separately in parallel batches of insects (adult females of Drosicha sp. and C. cephalonica). Recovery was found to be less than sorption showing that a part of the HCN absorbed is converted into a non-recoverable state. Further, that the weight of HCN sorbed per gram body weight of adult females of Drosicha sp. is much less than in the case of C. cephalonica under similar conditions of fumigation and that the amount of HCN converted into non-recoverable products is less in Drosicha adults than in C. cephalonica.A comparison of the water content of T. castaneum, C. cephalonica and Drosicha sp. (adults) showed that there was a positive correlation between water content and higher susceptibility to HCN and greater recovery of HCN was also indicated. It is suggested that this may be a factor in the “ Surface Resistance ” of an insec to a fumigant.The observations of previous workers that larger amounts are sorbed by or recovered (after fumigation) from more susceptible species than for those less susceptible was corroborated by the results obtained with C. cephalonica, T. castaneum and adult females of Drosicha sp. but not with those from nymphs of Drosicha sp.When dosage-mortality graphs were prepared by taking the amount of HCN recovered per gram body weight as an index of internal dose, the order of resistance of different test insects based on this new criterion was found to be entirely different from that based on the usual criterion of the concentration of HCN in the fumatorium being the index of effective dosage.These apparently anomalous observations may be explained by assuming that the resistance shown by an insect in an actual fumigation operation, i.e., to the concentration of HCN to which it is exposed (external dose) is what may be called the total “ Effective Resistance ” and that this “ Effective Resistance ” is the resultant of (a) “ Surface Resistance ” to the entry of fumigant and (b) “ Internal Resistance ” to the amount of HCN which actually gains entry into the body in some way or other. Thus the “Effective Resistance ” of an insect may be due to a combination either of low “ Surface Resistance ” and high “ Internal Resistance ”, giving a very low “ Effective Resistance ” as in the case of C. cephalonica, or vice versa giving the maximum “ Effective Resistance ” as in adult females of Drosicha sp. The lower recovery of HCN from the nymphs of Drosicha sp., although they were more susceptible to fumigation than C. cephalonica, is explained by their higher “ Surface Resistance ” combined with a very much lower “ Internal Resistance ”, leading to a lower “ Effective Resistance ”.

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A random hierarchical lattice: the series-parallel graph and its properties

Advances in Applied Probability ◽

10.1017/s0001867800013136 ◽

2004 ◽

Vol 36 (03) ◽

pp. 824-838 ◽

Cited By ~ 3

Author(s):

B. M. Hambly ◽

Jonathan Jordan

Keyword(s):

Phase Transition ◽

Random Graphs ◽

Effective Resistance ◽

First Passage Percolation ◽

Hierarchical Lattice ◽

First Passage ◽

In Series ◽

Parallel Graph

We consider a sequence of random graphs constructed by a hierarchical procedure. The construction replaces existing edges by pairs of edges in series or parallel with probability p. We investigate the effective resistance across the graphs, first-passage percolation on the graphs and the Cheeger constants of the graphs as the number of edges tends to infinity. In each case we find a phase transition at

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Frequency dependent resistance calculation of multiple conductors

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-02-2017-0093 ◽

2017 ◽

Vol 36 (5) ◽

pp. 1396-1410

Author(s):

Tomislav Župan ◽

Bojan Trkulja

Keyword(s):

Design Methodology ◽

Numerical Approach ◽

Effective Resistance ◽

Proximity Effects ◽

The Finite Element Method ◽

Frequency Range ◽

Frequency Dependent ◽

Content Type ◽

Electromagnetic Devices ◽

Practical Implications

Purpose The purpose of this paper is to present a method for calculating frequency-dependent resistance when multiple current-carrying conductors are present. Design/methodology/approach Analytical and numerical formulations are presented. Both skin- and proximity-effects are considered in the numerical approach, whereas only skin-effect can be taken into account in analytical equations. The calculation is done using a self-developed integral equation-based field solver. The results are benchmarked using professional software based on the finite element method (FEM). Findings Results from the numerical approach are in agreement with FEM-based software throughout the whole frequency range. Analytical formulations yield unsatisfactory results in higher frequency range. When multiple conductors are mutually relatively close, the proximity-effect has an impact on effective resistance and has to be taken into account. Research limitations/implications The methodology is presented using axially symmetrical conductors. However, the same procedure can be developed for straight conductors as well. Practical implications Presented fast and stable procedure can be used in most electromagnetic devices when frequency-dependent resistance needs to be precisely determined. Originality/value The value of the presented numerical methodology lies in its ability to take both skin- and proximity-effects into account. As conductors are densely packed in most electromagnetic devices, both effects influence the effective resistance. The method can be easily implemented using a self-developed solver and yields satisfactory results.

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