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Parsimonious reconstruction of network evolution

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Parsimonious reconstruction of network evolution

Lecture Notes in Computer Science

作者： Patro, Rob Sefer, Emre Malin, Justin Marçais, Guillaume Navlakha, Saket Kingsford, Carl Center for Bioinformatics and Computational Biology University of Maryland College Park MD 20742 United States Department of Computer Science University of Maryland College Park MD 20742 United States Computational Biology Bioinformatics and Genomics Concentration Biological Sciences Graduate Program University of Maryland College Park MD 20742 United States Program in Applied Mathematics Statistics and Scientific Computation University of Maryland College Park MD 20742 United States School of Computer Science Carnegie Mellon University Pittsburgh PA 15213 United States

ISBN: (纸本)9783642230370

We consider the problem of reconstructing a maximally parsimonious history of network evolution under models that support gene duplication and loss and independent interaction gain and loss. We introduce a combinatorial framework for encoding network histories, and we give a fast procedure that, given a set of duplication histories, in practice finds network histories with close to the minimum number of interaction gain or loss events. In contrast to previous studies, our method does not require knowing the relative ordering of unrelated duplication events. Results on simulated histories suggest that common ancestral networks can be accurately reconstructed using this parsimony approach. © 2011 Springer-Verlag.

关键词： Genes

Stability of ψ-hilfer impulsive fractional differential equations

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arXiv 2018年

作者： VANTERLER DA C. SOUSA, J. KUCCHE, KISHOR D. CAPELAS DE OLIVEIRA, E. Department of Applied Mathematics Institute of Mathematics Statistics and Scientific Computation University of Campinas - UNICAMP rua Sérgio Buarque de Holanda 651 Campinas SP13083-859 Brazil Department of Mathematics Shivaji University Kolhapur Maharashtra416 004 India

In this paper, we investigate the sufficient conditions for existence and uniqueness of solutions and δ-Ulam-Hyers-Rassias stability of an impulsive fractional differential equation involving ψ-Hilfer fractional derivative. Fixed point approach is used to obtain our main results.26A33, 34A08, 34A12, 34A37, 34DXX Copyright © 2018, The Authors. All rights reserved.

关键词： Differential equations

ONLINE TRAFFIC LIGHT CONTROL THROUGH GRADIENT ESTIMATION USING STOCHASTIC FLUID MODELS

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IFAC Proceedings Volumes 2005年第1期38卷 90-95页

作者： Christos G. Panayiotou William C. Howell Michael Fu Department of Electrical and Computer Engineering University of Cyprus Nicosia Cyprus Department of Mathematics Applied Mathematics Scientific Computation Program University of Maryland College Park MD 20742 USA Smith School of Business and Institute for Systems Research University of Maryland College Park MD 20742 USA

In this paper, we consider the problem of dynamically regulating the timing of traffic light controllers in busy cities. We use a Stochastic Fluid Model (SFM) to model the dynamics of the queues formed at an intersection. Based on this model, we derive gradients of the queue lengths with respect to the green/red light lengths within a signal cycle. We report preliminary numerical results comparing the performance of the estimates with finite-difference and smoothed perturbation analysis estimates. Then all estimators are used to optimize the traffic system via Stochastic Approximation.

关键词： Traffic control perturbation analysis stochastic approximation

Representing GASPEC with the world gas model

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Energy Journal 2009年第SPECIAL ISSUE 1期30卷 97-118页

作者： Egging, Ruud Holz, Franziska Von Hirschhausen, Christian Gabriel, Steven A. 1143 Glenn L. Martin Hall Dept of Civil and Environmental Engineering University of Maryland College Park MD 20742-3021 United States DIW Berlin 10117 Berlin Mohrenstr. 58 Germany Chair of Energy Economics and Public Sector Management TU Dresden 01062 Dresden Germany Applied Mathematics and Scientific Computation Program University of Maryland College Park MD 20742 United States

This paper presents results of simulating a more collusive behavior of a group of natural gas producing and exporting countries, sometimes called GASPEC. We use the World Gas Model, a dynamic, strategic representation of world gas production, trade, and consumption between 2005 and 2030. In particular, we simulate a closer cooperation of the GASPEC countries when exporting pipeline gas and liquefied natural gas;we also run a more drastic scenario where GASPEC countries deliberately hold back production. The results show that compared to our Base Case, a gas cartel would reduce total supplied quantities and induce price increases in gas importing countries up to 22%. There is evidence that the natural gas markets in Europe and North America would be affected more than other parts of the world. Lastly, the vulnerability of gas importers worldwide is further illustrated by the results of a sensitivity case in which price levels are up to 87% higher in Europe and North America. Copyright © 2009 by the IAEE. All rights reserved.

关键词： Cartels Liquefied natural gas Natural gas pipelines Supply Natural gas Financial investments Imports Natural gas production Liquefaction Fuel consumption

Non-Newtonian Fluid Flow in Micromachines: Magnetized Carreau Fluid Behavior with Slip and Viscous Dissipation at Inclined Stagnation Points

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SSRN

SSRN 2024年

作者： Liu, Hongjuan Khan, Shahzeb Dehraj, Sanaullah Haider, Ali Liu, Shengjun Ayub, Assad School of Mathematics and Statistics Central South University Hunan Changsha410083 China Department of Mathematics & Statistics Hazara University Manshera21300 Pakistan Department of Mathematics Government College Mansehra21300 Pakistan School of Mathematics and Statistics Xi’an Key Laboratory of Scientific Computation and Applied Statistics Northwestern Polytechnical University Xi’an710072 China Department of Mathematics and Statistics Quaid-e-Awam University of Engineering Science and Technology 67405 Sakrand Road Nawabshah Pakistan

Non-Newtonian fluid flow in micromachines has unique rheological properties and can be leveraged to enhance the performance and functionality of microscale devices. Viscosity of non-Newtonian fluid under different shear rates, can improve the efficiency of fluid transport, mixing, and control within micromachines. This paper presents the analysis of stagnation point flow of inclined magnetized Carreau fluid with slip constraints. This study employs a spectral relaxation method to analyze the flow and investigate the impacts of numerous parameters, such as the inclination angle and magnetic field strength. The study provides numerous applications in field of Chemical engineering and aerospace engineering. © 2024, The Authors. All rights reserved.

关键词： Porous materials

A new class of mild and strong solutions of integro-differential equation of arbitrary order in banach space

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arXiv 2018年

作者： Sousa, J. Vanterler Da C. Gomes, D.F. De Oliveira, E. Capelas Department of Applied Mathematics Institute of Mathematics Statistics and Scientific Computation University of Campinas – UNICAMP rua Sérgio Buarque de Holanda 651 Campinas SP13083–859 Brazil Department of Mathematics IFMA Barra do CordaMA65950-000 Brazil

The motivation that the field of differential equations provide to several researchers for the challenges that have been challenging them over the decades has contributed to the strengthening of the area within mathematics. In this sense, investigating important properties of solutions of differential equations, in particular fractional, has been object of study due to the exponential growth of the fractional calculus. In this paper, we investigate the existence and uniqueness of a new class of mild and strong solution of the fractional integro-differential equations in the Hilfer fractional derivative sense in Banach space, by means of the continuously C0-semigroup, Banach fixed point theorem and Gronwall inequality. Copyright © 2018, The Authors. All rights reserved.

关键词： Banach spaces

Can graph properties have exponential quantum speedup?

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arXiv 2020年

作者： Childs, Andrew M. Wang, Daochen Department of Computer Science Institute for Advanced Computer Studies Joint Center for Quantum Information and Computer Science University of Maryland Applied Mathematics Statistics and Scientific Computation Joint Center for Quantum Information and Computer Science University of Maryland

Quantum computers can sometimes exponentially outperform classical ones, but only for problems with sufficient structure. While it is well known that query problems with full permutation symmetry can have at most polynomial quantum speedup-even for partial functions-it is unclear how far this condition must be relaxed to enable exponential speedup. In particular, it is natural to ask whether exponential speedup is possible for (partial) graph properties, in which the input describes a graph and the output can only depend on its isomorphism class. We show that the answer to this question depends strongly on the input model. In the adjacency matrix model, we prove that the bounded-error randomized query complexity R of any graph property P has R(P) = O(Q(P)6), where Q is the bounded-error quantum query complexity. This negatively resolves an open question of Montanaro and de Wolf in the adjacency matrix model. More generally, we prove R(P) = O(Q(P)3l) for any l-uniform hypergraph property P in the adjacency matrix model. In direct contrast, in the adjacency list model for bounded-degree graphs, we exhibit a promise problem that shows an exponential separation between the randomized and quantum query complexities. Copyright © 2020, The Authors. All rights reserved.

关键词： Qubits

On the relationship between forecast accuracy and detection performance: An application to biosurveillance

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On the relationship between forecast accuracy and detection ...

IEEE Conference on Technologies for Homeland Security

作者： Thomas Lotze Galit Shmueli Applied Mathematics and Scientific Computation Program University of Maryland College Park MD USA Department of Decision Operations & Information Technologies and Center for Health and Information Decision Systems University of Maryland College Park MD USA

While many methods have been proposed for detecting disease outbreaks from pre-diagnostic data, their performance is usually not well understood. In this paper, we describe the relationship between forecast accuracy and the detection accuracy of a method. We argue that most existing temporal detection methods for biosurveillance can be characterized as a forecasting component coupled with a monitoring/detection component. We show that improved forecasting results in improved detection and we quantify the relationship between forecast accuracy and detection metrics under different scenarios. The forecast accuracy can then be used to rate an algorithm's expected performance in detecting outbreaks. Simulation is used to compare empirical performance with theoretical results; we also show examples with authentic biosurveillance data.

关键词： Control charts Yttrium Educational institutions Diseases Signal generators Bioinformatics Probability Condition monitoring Error correction statistics

On the existence and stability for non-instantaneous impulsive fractional integrodifferential equation

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arXiv 2018年

作者： Da C. Sousa, J. Vanterler Oliveira, D. Santos De Oliveira, E. Capelas Department of Applied Mathematics Institute of Mathematics Statistics and Scientific Computation University of Campinas - UNICAMP rua Sérgio Buarque de Holanda 651 CampinasSP13083-859 Brazil Coordination of Civil Engineering Technological Federal University of Parana Guarapuava85053- 525 Brazil

In this paper, by means of Banach fixed point theorem, we investigate the existence and Ulam-Hyers-Rassias stability of the non-instantaneous impulsive integrodif- ferential equation by means of δ-Hilfer fractional derivative. In this sense, some examples are presented, in order to consolidate the results *** Codes 26A33, 34A08, 34A12, 34K20, 34G20 Copyright © 2018, The Authors. All rights reserved.

关键词： Fixed point arithmetic