We study a model for a nonlinear mechanical oscillator, relevant to the dynamics of micro- and nanomechanical time-keeping devices, where periodic motion is sustained by a feedback force proportional to the oscillation velocity. Specifically, we focus our attention on the effect of a time delay in the feedback loop, assumed to originate in the electric circuit that creates and injects the self-sustaining force. Stationary oscillating solutions to the equation of motion, whose stability is insured by the crucial role of nonlinearity, are analytically obtained through suitable approximations. We show that a delay within the order of the oscillation period can suppress self-sustained oscillations. Numerical solutions are used to validate the analytical approximations. Received: 6 February 2017, Accepted: 8 March 2017; Edited by: A. Marti; Reviewed by: C. Masoller, Universitat Politecnica de Catalunya, Barcelona, Spain; DOI: http://dx.doi.org/10.4279/PIP.090003 Cite as: D. H. Zanette, Papers in Physics 9, 090003 (2017) This paper, by D. H. Zanette , is licensed under the Creative Commons Attribution License 3.0 .
{"title":"Self-sustained oscillations with delayed velocity feedback","authors":"D. Zanette","doi":"10.4279/PIP.090003","DOIUrl":"https://doi.org/10.4279/PIP.090003","url":null,"abstract":"We study a model for a nonlinear mechanical oscillator, relevant to the dynamics of micro- and nanomechanical time-keeping devices, where periodic motion is sustained by a feedback force proportional to the oscillation velocity. Specifically, we focus our attention on the effect of a time delay in the feedback loop, assumed to originate in the electric circuit that creates and injects the self-sustaining force. Stationary oscillating solutions to the equation of motion, whose stability is insured by the crucial role of nonlinearity, are analytically obtained through suitable approximations. We show that a delay within the order of the oscillation period can suppress self-sustained oscillations. Numerical solutions are used to validate the analytical approximations. Received: 6 February 2017, Accepted: 8 March 2017; Edited by: A. Marti; Reviewed by: C. Masoller, Universitat Politecnica de Catalunya, Barcelona, Spain; DOI: http://dx.doi.org/10.4279/PIP.090003 Cite as: D. H. Zanette, Papers in Physics 9, 090003 (2017) This paper, by D. H. Zanette , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2017-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46007411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper introduces an alternative formalism for deriving the Dirac operator and equation. The use of this formalism concomitantly generates a separate operator coupled to the Dirac operator. When operating on a Clifford field, this coupled operator produces field components which are formally equivalent to the field components of Maxwell's electromagnetic field tensor. Consequently, the Lagrangian of the associated coupled field exhibits internal local gauge symmetry. The coupled field Lagrangian is seen to be equivalent to the Lagrangian of Quantum Electrodynamics. Received: 8 November 2016, Accepted: 4 January 2017; Edited by: D. Gomez Dumm; DOI: http://dx.doi.org/10.4279/PIP.090002 Cite as: B J Wolk, Papers in Physics 9, 090002 (2017) This paper, by B J Wolk , is licensed under the Creative Commons Attribution License 3.0 .
{"title":"An alternative derivation of the Dirac operator generating intrinsic Lagrangian local gauge invariance","authors":"B. Wolk","doi":"10.4279/PIP.090002","DOIUrl":"https://doi.org/10.4279/PIP.090002","url":null,"abstract":"This paper introduces an alternative formalism for deriving the Dirac operator and equation. The use of this formalism concomitantly generates a separate operator coupled to the Dirac operator. When operating on a Clifford field, this coupled operator produces field components which are formally equivalent to the field components of Maxwell's electromagnetic field tensor. Consequently, the Lagrangian of the associated coupled field exhibits internal local gauge symmetry. The coupled field Lagrangian is seen to be equivalent to the Lagrangian of Quantum Electrodynamics. Received: 8 November 2016, Accepted: 4 January 2017; Edited by: D. Gomez Dumm; DOI: http://dx.doi.org/10.4279/PIP.090002 Cite as: B J Wolk, Papers in Physics 9, 090002 (2017) This paper, by B J Wolk , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2017-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47850746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, the problem of pedestrian egress under different geometries is studied by means of two numerical models. The length of the bottleneck after the exit and the distance of the exit to the lateral wall of a squared room are investigated. Both models show that an increase in the bottleneck length increases the evacuation time by more than 20 %, for any exit position. Hence, a bottleneck length tending to zero is the best choice. On the contrary, the results of moving the exit closer to the lateral wall are different in both models and, thus, its convenience cannot be stated. To unveil whether this layout modification is favorable, experimental data are required. Moreover, the discrepancy between models indicates that they should be validated considering several scenarios. Received: 25 August 2016, Accepted: 3 January 2017; Edited by: G. C. Barker; Reviewed by: A. Seyfried, Institute for Advanced Simulation Julich Supercomputing Centre, Germany; DOI: http://dx.doi.org/10.4279/PIP.090001 Cite as: D R Parisi, G A Patterson, Papers in Physics 9, 090001 (2017) This paper, by D R Parisi, G A Patterson , is licensed under the Creative Commons Attribution License 3.0 .
本文通过两个数值模型研究了不同几何形状下的行人出口问题。研究了方形房间出口后瓶颈的长度和出口到侧壁的距离。两个模型都表明，对于任何出口位置，瓶颈长度的增加都会使疏散时间增加20%以上。因此，趋向于零的瓶颈长度是最佳选择。相反，在两种模型中，将出口移近侧壁的结果不同，因此无法说明其便利性。为了揭示这种布局修改是否有利，需要实验数据。此外，模型之间的差异表明，应考虑几种情况对其进行验证。接收日期：2016年8月25日，接受日期：2017年1月3日；编辑：G.C.Barker；审核人：A.Seyfried，德国Julich超级计算中心高级模拟研究所；DOI：http://dx.doi.org/10.4279/PIP.090001引用自：D R Parisi，G A Patterson，《物理学论文》9，090001（2017）本文由D R Paris，G A帕特森撰写，根据知识共享归因许可证3.0获得许可。
{"title":"Influence of bottleneck lengths and position on simulated pedestrian egress","authors":"D. Parisi, G. Patterson","doi":"10.4279/PIP.090001","DOIUrl":"https://doi.org/10.4279/PIP.090001","url":null,"abstract":"In this paper, the problem of pedestrian egress under different geometries is studied by means of two numerical models. The length of the bottleneck after the exit and the distance of the exit to the lateral wall of a squared room are investigated. Both models show that an increase in the bottleneck length increases the evacuation time by more than 20 %, for any exit position. Hence, a bottleneck length tending to zero is the best choice. On the contrary, the results of moving the exit closer to the lateral wall are different in both models and, thus, its convenience cannot be stated. To unveil whether this layout modification is favorable, experimental data are required. Moreover, the discrepancy between models indicates that they should be validated considering several scenarios. Received: 25 August 2016, Accepted: 3 January 2017; Edited by: G. C. Barker; Reviewed by: A. Seyfried, Institute for Advanced Simulation Julich Supercomputing Centre, Germany; DOI: http://dx.doi.org/10.4279/PIP.090001 Cite as: D R Parisi, G A Patterson, Papers in Physics 9, 090001 (2017) This paper, by D R Parisi, G A Patterson , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2017-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48703521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the most reliable and widely used methods to calculate electronic structure of strongly correlated models is the Dynamical Mean Field Theory (DMFT) developed over two decades ago. It is a non-perturbative algorithm which, in its simplest version, takes into account strong local interactions by mapping the original lattice model on to a single impurity model. This model has to be solved using some many-body technique. Several methods have been used, the most reliable and promising of which is the Density Matrix Renormalization technique. In this paper, we present an optimized implementation of this method based on using the star geometry and correction-vector algorithms to solve the related impurity Hamiltonian and obtain dynamical properties on the real frequency axis. We show results for the half-filled and doped one-band Hubbard models on a square lattice. Received: 31 March 2017, Accepted: 6 June 2017; Edited by: D. Dominguez; Reviewed by: A. Feiguin, Northeastern University, Boston, United States; DOI: http://dx.doi.org/10.4279/PIP.090005 Cite as: Y Nunez Fernandez, K Hallberg, Papers in Physics 9, 090005 (2017) This paper, by Y Nunez Fernandez, K Hallberg , is licensed under the Creative Commons Attribution License 3.0 .
二十多年前发展起来的动态平均场理论(DMFT)是计算强相关模型电子结构最可靠、应用最广泛的方法之一。它是一种非微扰算法，在其最简单的版本中，通过将原始晶格模型映射到单个杂质模型上来考虑强局部相互作用。这个模型必须用一些多体技术来求解。有几种方法被使用，其中最可靠和最有前途的是密度矩阵重整化技术。在本文中，我们提出了一种基于星形几何和校正矢量算法的优化实现方法，以求解相关杂质哈密顿量并获得实频率轴上的动态特性。我们展示了正方形晶格上半填充和掺杂单波段哈伯德模型的结果。收稿日期:2017年3月31日，收稿日期:2017年6月6日;编辑:D. Dominguez;审评人:A. Feiguin，美国波士顿东北大学;Y Nunez Fernandez, K Hallberg, Papers in Physics 9,090005(2017)本文由Y Nunez Fernandez, K Hallberg撰写，使用知识共享署名许可3.0。
{"title":"An efficient impurity-solver for the dynamical mean field theory algorithm","authors":"Y. N. Fernández, K. Hallberg","doi":"10.4279/PIP.090005","DOIUrl":"https://doi.org/10.4279/PIP.090005","url":null,"abstract":"One of the most reliable and widely used methods to calculate electronic structure of strongly correlated models is the Dynamical Mean Field Theory (DMFT) developed over two decades ago. It is a non-perturbative algorithm which, in its simplest version, takes into account strong local interactions by mapping the original lattice model on to a single impurity model. This model has to be solved using some many-body technique. Several methods have been used, the most reliable and promising of which is the Density Matrix Renormalization technique. In this paper, we present an optimized implementation of this method based on using the star geometry and correction-vector algorithms to solve the related impurity Hamiltonian and obtain dynamical properties on the real frequency axis. We show results for the half-filled and doped one-band Hubbard models on a square lattice. Received: 31 March 2017, Accepted: 6 June 2017; Edited by: D. Dominguez; Reviewed by: A. Feiguin, Northeastern University, Boston, United States; DOI: http://dx.doi.org/10.4279/PIP.090005 Cite as: Y Nunez Fernandez, K Hallberg, Papers in Physics 9, 090005 (2017) This paper, by Y Nunez Fernandez, K Hallberg , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2017-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47226031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
É. Freyssingeas, Damien Frelat, Y. Dossmann, J. Géminard
A tank is filled with a non-Newtonian fluid. We report on the deformation of the free surface resulting from the presence of an underlying vortex. In a tiny range of the experimental parameters, the flow spontaneously loses its initial axi-symmetry, leading to the formation of a stationary knife-bladed vortex. We report on the series of patterns observed experimentally and summarize the conditions of existence of the latter by establishing a state diagram. Received: 1 July 2016, Accepted: 24 October 2016; Edited by: J. P. Hulin; Reviewed by: C. Nouar, LEMTA, Universite de Lorraine, Nancy, France; DOI: http://dx.doi.org/10.4279/PIP.080007 Cite as: E Freyssingeas, D Frelat, Y Dossmann, J-C Geminard, Papers in Physics 8, 080007 (2016) This paper, by E Freyssingeas, D Frelat, Y Dossmann, J-C Geminard , is licensed under the Creative Commons Attribution License 3.0 .
水箱里装满了非牛顿流体。我们报告了由于下伏涡的存在而引起的自由表面的变形。在实验参数的很小范围内，流动会自发地失去其初始轴对称，从而形成静止的刀叶涡。我们报告了实验观察到的一系列模式，并通过建立状态图总结了后者的存在条件。收稿日期:2016年7月1日，收稿日期:2016年10月24日;编辑:j·p·胡林;评审:C. Nouar, LEMTA，洛林大学，南希，法国;本文由E Freyssingeas, D Frelat, Y Dossmann, J-C Geminard撰写，采用知识共享署名许可3.0协议。
{"title":"Knife-bladed vortices in non-Newtonian fluids","authors":"É. Freyssingeas, Damien Frelat, Y. Dossmann, J. Géminard","doi":"10.4279/PIP.080007","DOIUrl":"https://doi.org/10.4279/PIP.080007","url":null,"abstract":"A tank is filled with a non-Newtonian fluid. We report on the deformation of the free surface resulting from the presence of an underlying vortex. In a tiny range of the experimental parameters, the flow spontaneously loses its initial axi-symmetry, leading to the formation of a stationary knife-bladed vortex. We report on the series of patterns observed experimentally and summarize the conditions of existence of the latter by establishing a state diagram. Received: 1 July 2016, Accepted: 24 October 2016; Edited by: J. P. Hulin; Reviewed by: C. Nouar, LEMTA, Universite de Lorraine, Nancy, France; DOI: http://dx.doi.org/10.4279/PIP.080007 Cite as: E Freyssingeas, D Frelat, Y Dossmann, J-C Geminard, Papers in Physics 8, 080007 (2016) This paper, by E Freyssingeas, D Frelat, Y Dossmann, J-C Geminard , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2016-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71010902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The study of fluctuation-induced transport is concerned with the directed motion of particles on a substrate when subjected to a fluctuating external field. Work over the last two decades provides now precise clues on how the average transport depends on three fundamental aspects: the shape of the substrate, the correlations of the fluctuations and the mass, geometry, interaction and density of the particles. These three aspects, reviewed here, acquire additional relevance because the same notions apply to a bewildering variety of problems at very different scales, from the small nano or micro-scale, where thermal fluctuations effects dominate, up to very large scales including ubiquitous cooperative phenomena in granular materials. Received: 30 October 2015, Accepted: 4 February 2016; Edited by: G. Martinez Mekler; Reviewed by: J. Mateos, Departamento de Sistemas Complejos, Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico.; DOI: http://dx.doi.org/10.4279/PIP.080004 Cite as: G P Suarez, M Hoyuelos, D R Chialvo, Papers in Physics 8, 080004 (2016) This paper, by G P Suarez, M Hoyuelos, D R Chialvo , is licensed under the Creative Commons Attribution License 3.0 .
涨落诱导输运的研究涉及到粒子在受涨落外场作用时在基底上的定向运动。过去二十年的工作现在提供了精确的线索，说明平均输运如何取决于三个基本方面:基底的形状、波动与质量的相关性、几何形状、粒子的相互作用和密度。这里回顾的这三个方面具有额外的相关性，因为相同的概念适用于非常不同尺度的各种令人眼花缭乱的问题，从热波动效应占主导地位的小纳米或微尺度，到非常大的尺度，包括颗粒材料中无处不在的合作现象。收稿日期:2015年10月30日，收稿日期:2016年2月4日;编辑:G. Martinez Mekler;审评人:墨西哥国立自治大学金融研究所综合系统系J. Mateos;本文作者G P Suarez, M Hoyuelos, D R Chialvo, Papers in Physics 8,0800004(2016)，采用知识共享署名许可3.0。
{"title":"Invited review: Fluctuation-induced transport. From the very small to the very large scales","authors":"G. Suárez, M. Hoyuelos, D. Chialvo","doi":"10.4279/PIP.080004","DOIUrl":"https://doi.org/10.4279/PIP.080004","url":null,"abstract":"The study of fluctuation-induced transport is concerned with the directed motion of particles on a substrate when subjected to a fluctuating external field. Work over the last two decades provides now precise clues on how the average transport depends on three fundamental aspects: the shape of the substrate, the correlations of the fluctuations and the mass, geometry, interaction and density of the particles. These three aspects, reviewed here, acquire additional relevance because the same notions apply to a bewildering variety of problems at very different scales, from the small nano or micro-scale, where thermal fluctuations effects dominate, up to very large scales including ubiquitous cooperative phenomena in granular materials. Received: 30 October 2015, Accepted: 4 February 2016; Edited by: G. Martinez Mekler; Reviewed by: J. Mateos, Departamento de Sistemas Complejos, Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico.; DOI: http://dx.doi.org/10.4279/PIP.080004 Cite as: G P Suarez, M Hoyuelos, D R Chialvo, Papers in Physics 8, 080004 (2016) This paper, by G P Suarez, M Hoyuelos, D R Chialvo , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2016-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71010892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We describe a simple experiment involving spheres rolling down an inclined plane towards a bottleneck and through a gap. Results of the experiment indicate that flow rate can be increased by placing an obstruction at optimal positions near the bottleneck. We use the experiment to develop a computer simulation using the PhysX physics engine. Simulations confirm the experimental results and we state several considerations necessary to obtain a model that agrees well with experiment. We demonstrate that the model exhibits clogging, intermittent and continuous flow, and that it can be used as a tool for further investigations in granular flow. Received: 22 November 2015, Accepted: 19 February 2016; Edited by: L. A. Pugnaloni; Reviewed by: C. M. Carlevaro, Instituto de Fisica de Liquidos y Sistemas Biologicos, La Plata, Argentina; DOI: http://dx.doi.org/10.4279/PIP.080003 Cite as: A Murray, F Alonso-Marroquin, Papers in Physics 8, 080003 (2016) This paper, by A Murray, F Alonso-Marroquin , is licensed under the Creative Commons Attribution License 3.0 .
我们描述了一个简单的实验，涉及球体沿斜面滚向瓶颈并穿过间隙。实验结果表明，在靠近瓶颈的最佳位置放置障碍物可以提高流量。我们利用这个实验开发了一个使用PhysX物理引擎的计算机模拟。仿真结果证实了实验结果，并提出了建立与实验结果吻合的模型所需要考虑的几个问题。我们证明，该模型显示堵塞，间歇和连续流动，它可以用作进一步研究颗粒流动的工具。收稿日期:2015年11月22日，收稿日期:2016年2月19日;编辑:L. A. Pugnaloni;审评人:C. M. Carlevaro，阿根廷拉普拉塔市生物系统与液体科学研究所;A Murray, F Alonso-Marroquin, Papers in Physics 8,080003(2016)本文采用知识共享署名许可3.0。
{"title":"Increasing granular flow rate with obstructions","authors":"Alan T. Murray, F. Alonso-marroquin","doi":"10.4279/PIP.080003","DOIUrl":"https://doi.org/10.4279/PIP.080003","url":null,"abstract":"We describe a simple experiment involving spheres rolling down an inclined plane towards a bottleneck and through a gap. Results of the experiment indicate that flow rate can be increased by placing an obstruction at optimal positions near the bottleneck. We use the experiment to develop a computer simulation using the PhysX physics engine. Simulations confirm the experimental results and we state several considerations necessary to obtain a model that agrees well with experiment. We demonstrate that the model exhibits clogging, intermittent and continuous flow, and that it can be used as a tool for further investigations in granular flow. Received: 22 November 2015, Accepted: 19 February 2016; Edited by: L. A. Pugnaloni; Reviewed by: C. M. Carlevaro, Instituto de Fisica de Liquidos y Sistemas Biologicos, La Plata, Argentina; DOI: http://dx.doi.org/10.4279/PIP.080003 Cite as: A Murray, F Alonso-Marroquin, Papers in Physics 8, 080003 (2016) This paper, by A Murray, F Alonso-Marroquin , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2016-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71010778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. I. P. Rossell'o, R. Deza, J. Ignacio Deza, H. Wio
Aiming to optimize piezoelectric energy harvesting from strongly col-ored fat-tailed fluctuations, we have recently studied the performance ofa monostable inertial device under a noise whose statistics depends on aparameter q (bounded for q 1).We have studied the interplay between the potential shape (interpolatingbetween square-well and harmonic-like behaviors) and the noise’s statis-tics and spectrum, and showed that its output power grows as q increasesabove 1. We now report a real experiment on an electronic analog of theproposed system, which sheds light on its operating principle. Received: 20 Novembre 2014, Accepted: 7 September 2015; Edited by: C. A. Condat, G. J. Sibona; DOI: http://dx.doi.org/10.4279/PIP.070014 Cite as: J I Pena Rossello, R Deza, J . Deza, H S Wio , Papers in Physics 7, 070014 (2015) This paper, by J. I. Pena Rossello, R. R. Deza, J. I. Deza, H. S. Wio , is licensed under the Creative Commons Attribution License 3.0 .
为了优化压电从强色厚尾波动中获取能量，我们最近研究了单稳定惯性器件在统计量依赖于参数q (q为有界)的噪声下的性能。我们研究了潜在形状(方阱和类谐波行为之间的插值)与噪声统计量和频谱之间的相互作用，并表明其输出功率随着q的增加而增加。我们现在报告一个关于所提出的系统的电子模拟的真实实验，它揭示了它的工作原理。收稿日期:2014年11月20日，收稿日期:2015年9月7日;编辑:C. A. Condat, G. J. Sibona;DOI: http://dx.doi.org/10.4279/PIP.070014出处:J I Pena Rossello, R Deza, J。本文由j.i. Pena Rossello, r.r. Deza, j.i. Deza, h.s. Wio撰写，采用知识共享署名许可3.0协议。
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E. Hern'andez-Lemus, K. Baca-L'opez, R. Lemus, R. Garc'ia-Herrera
Gene regulatory networks present a wide variety of dynamical responses to intrinsic and extrinsic perturbations. Arguably, one of the most important of such coordinated responses is the one of amplification cascades, in which activation of a few key-responsive transcription factors (termed master regulators, MRs) lead to a large series of transcriptional activation events. This is so since master regulators are transcription factors controlling the expression of other transcription factor molecules and so on. MRs hold a central position related to transcriptional dynamics and control of gene regulatory networks and are often involved in complex feedback and feedforward loops inducing non-trivial dynamics. Recent studies have pointed out to the myocyte enhancing factor 2C (MEF2C, also known as MADS box transcription enhancer factor 2, polypeptide C) as being one of such master regulators involved in the pathogenesis of primary breast cancer. In this work, we perform an integrative genomic analysis of the transcriptional regulation activity of MEF2C and its target genes to evaluate to what extent are these molecules inducing collective responses leading to gene expression deregulation and carcinogenesis. We also analyzed a number of induced dynamic responses, in particular those associated with transcriptional bursts, and nonlinear cascading to evaluate the influence they may have in malignant phenotypes and cancer. Received: 20 Novembre 2014, Accepted: 24 June 2015; Edited by: C. A. Condat, G. J. Sibona; DOI: http://dx.doi.org/10.4279/PIP.070011 Cite as: E Hernandez-Lemus, K Baca-Lopez, R Lemus, R Garcia-Herrera, Papers in Physics 7, 070011 (2015) This paper, by E Hernandez-Lemus, K Baca-Lopez, R Lemus, R Garcia-Herrera , is licensed under the Creative Commons Attribution License 3.0 .
基因调控网络对内在和外在扰动呈现出各种各样的动态响应。可以说，这种协调反应中最重要的一个是扩增级联反应，其中几个关键响应转录因子(称为主调控因子，MRs)的激活导致大量的转录激活事件。这是因为主调控因子是控制其他转录因子分子表达的转录因子等等。MRs在转录动力学和基因调控网络的控制中占据中心位置，经常参与复杂的反馈和前馈循环，诱导非平凡的动力学。近年来的研究指出，肌细胞增强因子2C (MEF2C，也称为MADS盒转录增强因子2，多肽C)是参与原发性乳腺癌发病机制的主要调控因子之一。在这项工作中，我们对MEF2C及其靶基因的转录调控活性进行了综合基因组分析，以评估这些分子在多大程度上诱导集体反应，导致基因表达失调和致癌。我们还分析了一些诱导的动态反应，特别是那些与转录爆发和非线性级联相关的反应，以评估它们在恶性表型和癌症中可能产生的影响。收稿日期:2014年11月20日，收稿日期:2015年6月24日;编辑:C. A. Condat, G. J. Sibona;E Hernandez-Lemus, K Baca-Lopez, R Lemus, R Garcia-Herrera, Papers in Physics 7,070011(2015)本文由E Hernandez-Lemus, K Baca-Lopez, R Lemus, R Garcia-Herrera根据知识共享署名许可3.0授权。
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Diffusion mediated reaction models are particularly ubiquitous in the description of physical, chemical or biological processes. The random walk schema is a useful tool for formulating these models. Recently, evanescent random walk models have received attention in order to include finite lifetime processes. For instance, activated chemical reactions, such as laser photolysis, exhibit a different asymptotic limit when compared with immortal walker models. A diffusion limited reaction model based on a one dimensional continuous time random walk on a lattice with evanescent walkers is presented here. The absorption probability density and the reaction rate are analytically calculated in the Laplace domain. A finite absorption rate is considered, a model usually referred to as imperfect trapping. Short and long time behaviors are analyzed. Received: 20 Novembre 2014, Accepted: 20 March 2015; Edited by: C. A. Condat, G. J. Sibona; DOI: http://dx.doi.org/10.4279/PIP.070003 Cite as: M A Re, N C Bustos, Papers in Physics 7, 070003 (2015) This paper, by Miguel A. Re, Natalia C. Bustos , is licensed under the Creative Commons Attribution License 3.0 .
扩散介导的反应模型在描述物理、化学或生物过程中特别普遍。随机漫步模式是制定这些模型的有用工具。近年来，逐渐消失的随机漫步模型因其包含有限寿命过程而受到关注。例如，与不朽的沃克模型相比，激活的化学反应，如激光光解反应，表现出不同的渐近极限。本文提出了一种基于一维连续时间随机行走的扩散限制反应模型。在拉普拉斯域中解析计算了吸收概率、密度和反应速率。考虑有限吸收率，这种模型通常称为不完全俘获。分析了短时间和长时间的行为。收稿日期:2014年11月20日，收稿日期:2015年3月20日;编辑:C. A. Condat, G. J. Sibona;本文由Miguel A. Re, Natalia C. Bustos撰写，采用知识共享署名许可3.0协议。
{"title":"Reaction rate in an evanescent random walkers system","authors":"M. R'e, N. Bustos","doi":"10.4279/PIP.070003","DOIUrl":"https://doi.org/10.4279/PIP.070003","url":null,"abstract":"Diffusion mediated reaction models are particularly ubiquitous in the description of physical, chemical or biological processes. The random walk schema is a useful tool for formulating these models. Recently, evanescent random walk models have received attention in order to include finite lifetime processes. For instance, activated chemical reactions, such as laser photolysis, exhibit a different asymptotic limit when compared with immortal walker models. A diffusion limited reaction model based on a one dimensional continuous time random walk on a lattice with evanescent walkers is presented here. The absorption probability density and the reaction rate are analytically calculated in the Laplace domain. A finite absorption rate is considered, a model usually referred to as imperfect trapping. Short and long time behaviors are analyzed. Received: 20 Novembre 2014, Accepted: 20 March 2015; Edited by: C. A. Condat, G. J. Sibona; DOI: http://dx.doi.org/10.4279/PIP.070003 Cite as: M A Re, N C Bustos, Papers in Physics 7, 070003 (2015) This paper, by Miguel A. Re, Natalia C. Bustos , is licensed under the Creative Commons Attribution License 3.0 .","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2015-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71010287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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