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Platteville, WI, United States

University of Wisconsin–Platteville is a public university located in Platteville, Wisconsin, United States. Part of the University of Wisconsin System, it offers both bachelor and master degrees. The university has three colleges that serve over 8,000 students on-campus and an additional 3,000 students through its five distance education programs. Wikipedia.

Li W.,University of Wisconsin - Platteville
IEEE Journal of Quantum Electronics | Year: 2010

Transfer matrix method has been widely used to investigate the quantum phenomena in semiconductor materials and optoelectronic devices with an arbitrary potential profile. Free wave or complex exponential form transfer matrix method is easy to implement and also proved to be an efficient and accurate approach. However, there are numerical singularities in these kinds of matrices when the electron energy is equal to the potentials of certain segments. The singularity greatly limits the applications of this method. In this paper, by investigating the local zero energy problem of the Schrdinger equation, a generalized free wave transfer matrix method is formulated without any singular point in all possible electron energy range. Its validity and accuracy are shown both mathematically and numerically. The application is demonstrated by an example related to quantum well intermixing effect. © 2010 IEEE. Source

Haasl R.J.,University of Wisconsin - Platteville | Payseur B.A.,University of Wisconsin - Madison
Molecular Ecology | Year: 2016

Genomewide scans for natural selection (GWSS) have become increasingly common over the last 15 years due to increased availability of genome-scale genetic data. Here, we report a representative survey of GWSS from 1999 to present and find that (i) between 1999 and 2009, 35 of 49 (71%) GWSS focused on human, while from 2010 to present, only 38 of 83 (46%) of GWSS focused on human, indicating increased focus on nonmodel organisms; (ii) the large majority of GWSS incorporate interpopulation or interspecific comparisons using, for example FST, cross-population extended haplotype homozygosity or the ratio of nonsynonymous to synonymous substitutions; (III) most GWSS focus on detection of directional selection rather than other modes such as balancing selection; and (iv) in human GWSS, there is a clear shift after 2004 from microsatellite markers to dense SNP data. A survey of GWSS meant to identify loci positively selected in response to severe hypoxic conditions support an approach to GWSS in which a list of a priori candidate genes based on potential selective pressures are used to filter the list of significant hits a posteriori. We also discuss four frequently ignored determinants of genomic heterogeneity that complicate GWSS: mutation, recombination, selection and the genetic architecture of adaptive traits. We recommend that GWSS methodology should better incorporate aspects of genomewide heterogeneity using empirical estimates of relevant parameters and/or realistic, whole-chromosome simulations to improve interpretation of GWSS results. Finally, we argue that knowledge of potential selective agents improves interpretation of GWSS results and that new methods focused on correlations between environmental variables and genetic variation can help automate this approach. © 2015 John Wiley & Sons Ltd. Source

Summers S.M.,University of Wisconsin - Platteville
Algorithmica | Year: 2012

This paper concerns the self-assembly of scaled-up versions of arbitrary finite shapes.We work in the multiple temperature model that was introduced by Aggarwal, Cheng, Goldwasser, Kao, and Schweller (Complexities for Generalized Models of Self-Assembly, SIAM J. Comput. 2005). The multiple temperature model is a natural generalization of Winfree's abstract tile assembly model, where the temperature of a tile system is allowed to be shifted up and down as self-assembly proceeds. We first exhibit two constant-size tile sets in which scaled-up versions of arbitrary shapes self-assemble. Our first tile set has the property that each scaled shape selfassembles via an asymptotically "Kolmogorov-optimum" temperature sequence but the scaling factor grows with the size of the shape being assembled. In contrast, our second tile set assembles each scaled shape via a temperature sequence whose length is proportional to the number of points in the shape but the scaling factor is a constant independent of the shape being assembled. We then show that there is no constantsize tile set that can uniquely assemble an arbitrary (non-scaled, connected) shape in the multiple temperature model, i.e., the scaling is necessary for self-assembly. This answers an open question of Kao and Schweller (Proceedings of the 17th Annual ACM-SIAM Symposium on Discrete Algorithms (SODA 2006), pp. 571-580, 2006), who asked whether such a tile set exists. © Springer Science+Business Media, LLC 2011. Source

Teng H.,University of Wisconsin - Platteville
Finite Elements in Analysis and Design | Year: 2013

This paper considers the problem of prediction of the effective Young's modulus of a particulate composite material containing fractured particles. It treats the general case in which some particles are fractured while others remain intact. The reinforcing particles are assumed to be spherical. The Mori-Tanaka model is extended to formulate the method of solution. The resulting auxiliary problem of a single fractured particle in an infinite matrix subjected to a remote stress equal to the average matrix stress, for which Eshelby's solution does not exist, is solved by the finite element method. The predictions are compared with the exact results of Young's modulus for particulate composites with body-centered cubic packing arrangement and experimental results of Young's modulus for particulate composites containing fractured particles. © 2012 Elsevier B.V. Source

Stanojev I.,University of Wisconsin - Platteville | Yener A.,Pennsylvania State University
IEEE Transactions on Wireless Communications | Year: 2013

Cooperative jamming paradigm in secure communications enlists network nodes to transmit noise or structured codewords, in order to impair the eavesdropper's ability to decode messages to be kept confidential from it. Such an approach can significantly help in facilitating secure communication between legitimate parties but, by definition, assumes dedicated and/or altruistic nodes willing to act as cooperative jammers. In this paper, it is demonstrated that cooperative jamming leads to meaningful secrecy rate improvements even when this assumption is removed. A distributed mechanism is developed that motivates jamming participation of otherwise non-cooperative terminals, by compensating them with an opportunity to use the fraction of legitimate parties' spectrum for their own data traffic. With the goal of maximizing their data transmission rate priced by the invested power, cooperative jammers provide the jamming/transmitting power that is generally proportional to the amount of leased bandwidth. The fully decentralized framework is facilitated through a game-theoretic model, with the legitimate parties as the spectrum owners acting as the game leader, and the set of assisting jammers constituting the follower. To facilitate the behavior of non-cooperative and competitive multiple jammers, auctioning and power control mechanisms are applied for a follower sub-game in a two-layer leader-follower game framework. © 2013 IEEE. Source

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