检索结果-内蒙古大学图书馆

arXiv 2017年

作者： Zibetti, Marcelo V. W. Lin, Chuan Herman, Gabor T. Graduate Program in Electrical Engineering and Computer Science Federal University of Technology - Paraná Curitiba80230-901 Brazil School of Electrical Engineering Southwest Jiaotong University Chengdu Sichuan610031 China Department of Computer Science Graduate Center City University of New York New YorkNY10016 United States

The conjugate gradient (CG) method is commonly used for the relatively-rapid solution of least squares problems. In image reconstruction, the problem can be ill-posed and also contaminated by noise;due to this, approaches such as regularization should be utilized. Total variation (TV) is a useful regularization penalty, frequently utilized in image reconstruction for generating images with sharp edges. When a non-quadratic norm is selected for regularization, as is the case for TV, then it is no longer possible to use CG. Nonlinear CG is an alternative, but it does not share the efficiency that CG shows with least squares and methods such as fast iterative shrinkage-thresholding algorithms (FISTA) are preferred for problems with TV norm. A different approach to including prior information is superiorization. In this paper it is shown that the conjugate gradient method can be superiorized. Five different CG variants are proposed, including preconditioned CG. The CG methods superiorized by the total variation norm are presented and their performance in image reconstruction is demonstrated. It is illustrated that some of the proposed variants of the superiorized CG method can produce reconstructions of superior quality to those produced by FISTA and in less computational time, due to the speed of the original CG for least squares problems. In the Appendix we examine the behavior of one of the superiorized CG methods (we call it S-CG);one of its input parameters is a positive number ". It is proved that, for any given " that is greater than the half-squared-residual for the least squares solution, S-CG terminates in a finite number of steps with an output for which the half-squared-residual is less than or equal to ". Importantly, it is also the case that the output will have a lower value of TV than what would be provided by unsuperiorized CG for the same value " of the half-squared residual. Copyright © 2017, The Authors. All rights reserved.

关键词： Conjugate gradient method

来源：评论

学校读者我要写书评

暂无评论

Selective strong structural minimum cost resilient co-design for regular descriptor linear systems

arXiv

引用

arXiv 2017年

作者： Popli, Nipun Pequito, Sérgio Kar, Soummya Pedro Aguiar, A. Ilić, Marija Department of Electrical and Computer Engineering Carnegie Mellon University PittsburghPA15213 United States Department of Electrical and Systems Engineering School of Engineering and Applied Science University of Pennsylvania PhiladelphiaPA19104 United States Institute for System and Robotics Instituto Superior Técnico University of Lisbon Lisbon Portugal Porto Portugal

This paper addresses the problem of minimum cost resilient actuation-sensing-communication co-design for regular descriptor systems while ensuring selective strong structural system's properties. More specifically, the problem consists of determining the minimum cost deployment of actuation and sensing technology, as well as communication between the these, such that decentralized control approaches are viable for an arbitrary realization of regular descriptor systems satisfying a pre-specified selective structure, i.e., some entries can be zero, nonzero, or either zero/nonzero. Towards this goal, we rely on strong structural systems theory and extend it to cope with the selective structure that casts resiliency/robustness properties and uncertainty properties of system's model. Upon such framework, we introduce the notion of selective strong structural fixed modes as a characterization of the feasibility of decentralized control laws. Also, we provide necessary and sufficient conditions for this property to hold, and show how these conditions can be leveraged to determine the minimum cost resilient placement of actuation-sensing-communication technology ensuring feasible solutions. In particular, we study the minimum cost resilient actuation and sensing placement, upon which we construct the solution to our problem. Finally, we illustrate the applicability the main results of this paper on an electric power grid example. Copyright © 2017, The Authors. All rights reserved.

关键词： Describing functions

来源：评论

学校读者我要写书评

暂无评论

Quantum annealing versus classical machine learning applied to a simplified computational biology problem

arXiv

引用

arXiv 2018年

作者： Li, Richard Di Felice, Rosa Rohs, Remo Lidar, Daniel Department of Chemistry University of Southern California Los AngelesCA90089 United States Computational Biology and Bioinformatics Program Department of Biological Sciences University of Southern California Los AngelesCA90089 United States Center for Quantum Information Science & Technology University of Southern California Los AngelesCA90089 United States Department of Physics and Astronomy University of Southern California Los AngelesCA90089 United States Center S3 CNR Institute of Nanoscience Via Campi 213/A Modena41125 Italy Department of Computer Science University of Southern California Los AngelesCA90089 United States Department of Electrical Engineering University of Southern California Los AngelesCA90089 United States

Transcription factors regulate gene expression, but how these proteins recognize and specifically bind to their DNA targets is still debated. Machine learning models are effective means to reveal interaction mechanisms. Here we studied the ability of a quantum machine learning approach to predict binding specificity. Using simplified datasets of a small number of DNA sequences derived from actual binding affinity experiments, we trained a commercially available quantum annealer to classify and rank transcription factor binding. The results were compared to state-of-the-art classical approaches for the same simplified datasets, including simulated annealing, simulated quantum annealing, multiple linear regression, LASSO, and extreme gradient boosting. Despite technological limitations, we find a slight advantage in classification performance and nearly equal ranking performance using the quantum annealer for these fairly small training data sets. Thus, we propose that quantum annealing might be an effective method to implement machine learning for certain computational biology problems. Copyright © 2018, The Authors. All rights reserved.

关键词： Simulated annealing

来源：评论

学校读者我要写书评

暂无评论

Self-Catalyzed Core-Shell GaAs/GaNAs Nanowires Grown on Patterned Si(111)by Gas-Source Molecular Beam Epitaxy

Self-Catalyzed Core-Shell GaAs/GaNAs Nanowires Grown on Patt...

引用

第十二届全国分子束外延学术会议

作者： Rui La Ren Liu Weichuan Yao Mattias Janssond Shula Chend Janet L.Pan Irina A.Buyanovad S.A.Dayeh Charles W.Tu Graduate Program of Material Science and Engineering University of CaliforniaSan DiegoLa JollaCal Department of Electrical and Computer Engineering University of CaliforniaSan DiegoLa JollaCalifo Department of Physics Chemistry and BiologyLink(o)ping UniversityLink(o)pingSweden 58183 Graduate Program of Material Science and Engineering University of CaliforniaSan DiegoLa JollaCal

Group Ⅲ-Ⅴ semiconductor nanowires(NWs) on Si platform have attracted an increasing interest in recent *** integrating the direct band gap Ⅲ-Ⅴ materials that have high absorption coefficient onto the cost-effective Si platform,it would create novel optoelectronic devices for Si *** advantage of Ⅲ-Ⅴ nanowires grown on Si substrate is that the lattice-match constraint can be relaxed.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Acoustic supercoupling in a zero-compressibility waveguide

arXiv

引用

arXiv 2018年

作者： Esfahlani, H. Byrne, M.S. McDermott, M. Alù, A. Photonics Initiative Advanced Science Research Center City University of New York New York CityNY10031 United States Department of Electrical and Computer Engineering University of Texas at Austin AustinTX78712 United States LausanneCH-1015 Switzerland Naval Surface Warfare Center Carderock Division West BethesdaMD20817 United States Physics Program Graduate Center City University of New York New York CityNY10026 United States Department of Electrical Engineering City College of New York New York CityNY10031 United States

Funneling acoustic waves through largely mismatched channels is of fundamental importance to tailor and transmit sound for a variety of applications. In electromagnetics, zero-permittivity metamaterials have been used to enhance the coupling of energy in and out of ultranarrow channels, based on a phenomenon known as supercoupling. These metamaterial channels can support total transmission and complete phase uniformity, independent of the channel length, despite being geometrically mismatched to their input and output ports. In the field of acoustics, this phenomenon is challenging to achieve, since it requires zero-density metamaterials, typically realized with waveguides periodically loaded with membranes or resonators. Compared to electromagnetics, the additional challenge is due to the fact that conventional acoustic waveguides do not support a cut-off for the dominant mode of propagation, and therefore zero-index can be achieved only based on a collective resonance of the loading elements. Here we propose and experimentally realize acoustic supercoupling in a dual regime, using a compressibility-near-zero acoustic channel. Rather than engineering the channel with subwavelength inclusions, we operate at the cut-off of a higher-order acoustic mode, demonstrating the realization and efficient excitation of a zero-compressibility waveguide with effective soft boundaries. We experimentally verify strong transmission through a largely mismatched channel and uniform phase distribution, independent of the channel length. Our results open interesting pathways towards the realization of extreme acoustic parameters, and their implementation in relevant applications, such as ultrasound imaging, sonar technology, and sound transmission. Copyright © 2018, The Authors. All rights reserved.

关键词： Compressibility

来源：评论

学校读者我要写书评

暂无评论

A Bayesian mixture model for clustering on the stiefel manifold

arXiv

引用

arXiv 2017年

作者： Sengupta, Subhajit Pal, Subhadip Mitra, Riten Guo, Ying Banerjee, Arunava Ji, Yuan Program for Computational Genomics and Medicine NorthShore University HealthSystem Department of Bioinformatics and Biostatistics University of Louisville Department of Biostatistics and Bioinformatics Emory University Department of Computer and Information Science and Engineering University of Florida Department of Public Health Sciences University of Chicago

Analysis of a Bayesian mixture model for the Matrix Langevin distribution on the Stiefel manifold is presented. The model exploits a particular parametrization of the Matrix Langevin distribution, various aspects of which are elaborated on. A general, and novel, family of conjugate priors, and an efficient Markov chain Monte Carlo (MCMC) sampling scheme for the corresponding posteriors is then developed for the mixture model. Theoretical properties of the prior and posterior distributions, including posterior consistency, are explored in detail. Extensive simulation experiments are presented to validate the efficacy of the framework. Real-world examples, including a large scale neuroimaging dataset, are analyzed to demonstrate the computational tractability of the approach. Copyright © 2017, The Authors. All rights reserved.

关键词： Mixtures

来源：评论

学校读者我要写书评

暂无评论

Transistors: Biaxially Stretchable Fully Elastic Transistors Based on Rubbery Semiconductor Nanocomposites (Adv. Mater. Technol. 6/2018)

引用

Advanced Materials Technologies 2018年第6期3卷

作者： Hae-Jin Kim Anish Thukral Sahil Sharma Cunjiang Yu Department of Mechanical Engineering University of Houston Houston TX 77204 USA Materials Science and Engineering Program University of Houston Houston TX 77204 USA Department of Electrical and Computer Engineering University of Houston Houston TX 77204 USA Department of Biomedical Engineering University of Houston Houston TX 77204 USA

来源：评论

学校读者我要写书评

暂无评论

Adaptive control for an uncertain robotic manipulator with input saturations

引用

Control Theory and Technology 2016年第2期14卷 113-121页

作者： Trong-Toan TRAN Shuzhi Sam GE Wei HE Center for Robotics and School of Automation Engineering University of Electronic Science and Technology of China (UESTC) Chengdu Sichuan 611731 China Department of Electrical and Computer Engineering National University of Singapore Singapore 117576 Faculty of Electronic Technology Industrial University of rio Chi Minh City Ho Chi Minh City Vietnam School of Automation and Electrical Engineering University of Science and Technology Beijing Beijing 100083 China

In this paper, we address the control problem of an uncertain robotic manipulator with input saturations, unknown input scalings and disturbances. For this purpose, a model reference adaptive control like （MRAC-like） is used to handle the input saturations. The model reference is input to state stable （ISS） and driven by the errors between the required control signals and input saturations. The uncertain parameters are dealt with by using linear-in-the-parameters property of robotic dynamics, while unknown input scalings and disturbances are handled by non-regressor based approach. Our design ensures that all the signals in the closed-loop system are bounded, and the tracking error converges to the compact set which depends on the predetermined bounds of the control inputs. Simulation on a planar elbow manipulator with two joints is provided to illustrate the effectiveness of the proposed controller.

关键词： Robotic manipulator adaptive control uncertain parameter input saturation trajectory tracking

来源：评论

学校读者我要写书评

暂无评论

Designing the Application of Security Text Messages Into Audio Files Using Data Encryption Standard (DES) Algorithms Using the End Of File (EOF) Method

引用

Journal of Physics: Conference Series 2019年第1期1363卷 012078-012078页

作者： Pardede, A M H Anggi Pramana Zarlis, Muhammad Iskandar, Akbar Manurung, Rosida Tiurma Sriadhi, S Kurniawan, Citra Hasibuan, Abdurrozzaq Nurintan Asyiah Siregar Sari, Ayu Esteka Mulyaningsih, Indrya Teguh Hidayat Iskandar Alam Ibrahim Listyorini, Tri Winarno, Edy Tulus STMIK Kaputama Binjai Sumatera Utara Indonesia Department of Computer Science Universitas Sumatera Utara Medan Indonesia Department of Informatics STMIK AKBA Makassar Indonesia Graduate Program in Scientific Psychology Universitas Kristen Maranatha Indonesia Department of Electrical Engineering Universitas Negeri Medan Indonesia Department of Electrical Engineering Sekolah Tinggi Teknik Malang Indonesia Faculty of Engineering Universitas Islam Sumatera Utara Medan Indonesia Department of Management STIE Labuhanbatu Sumatera Utara Indonesia Department of Management STIE Sakti Alam Kerinci Jambi Indonesia Department of Indonesian Language Teaching Institut Agama Islam Negeri Syekh Nurjati Cirebon Indonesia Department of Informatics Engineering Universitas Muhammadiyah Sorong Sorong Indonesia Department of English Education Universitas Muhammadiyah Sorong Sorong Indonesia Department of Informatics Universitas Muria Kudus Indonesia Faculty of Information Technology Universitas Stikubank Semarang Indonesia Department of Mathematics Universitas Sumatera Utara Medan Indonesia

There are several ways to deal with security issues of confidential data sent via the internet, including using cryptographic techniques and steganography. Steganography is the science and art of concealing information / messages in a media in such a way that its existence is not detected by other parties who are not entitled to the information. Instead, cryptography disguises the meaning of a message, but does not hide that there is a message because the file looks suspicious. The Steganography technique used here was End Of File (EOF). The EOF technique described how to add data or files at the end of the image file. For this technique, the size of data or files that will be hidden could be larger than the size of the image file. The hidden data will be inserted at the end of the file so that it will not affect the image. This steganography application is also equipped with a cryptographic function Data Encryption Standard (DES) at the time of insertion of data that functions as a generator code and encrypts data, so that the security of a data in the file is more protected and protected from those who are not entitled to know the data.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Persistent homology: A step-by-step introduction for newcomers

Persistent homology: A step-by-step introduction for newcome...

引用

2016 Italian Chapter Conference - Smart Tools and Apps in computer Graphics, STAG 2016

作者： Fugacci, U. Scaramuccia, S. Iuricich, F. de Floriani, L. Department of Computer Science UMIACS University of Maryland College ParkMD United States Department of Computer Science Bioengineering Robotics and Systems Engineering University of Genova Genova Italy Department of Geographical Sciences University of Maryland College ParkMD United States

ISBN: (纸本)9783038680260

Persistent homology is a powerful notion rooted in topological data analysis which allows for retrieving the essential topological features of an object. The attention on persistent homology is constantly growing in a large number of application domains, such as biology and chemistry, astrophysics, automatic classification of images, sensor and social network analysis. Thus, an increasing number of researchers is now approaching to persistent homology as a tool to be used in their research activity. At the same time, the literature lacks of tools for introducing beginners to this topic, especially if they do not have a strong mathematical background in algebraic topology. We propose here two complementary tools which meet this requirement. The first one is a web-based user-guide equipped with interactive examples to facilitate the comprehension of the notions at the basis of persistent homology. The second one is an interactive tool, with a specific focus on shape analysis, developed for studying persistence pairs by visualizing them directly on the input complex. © 2016 The Author(s) Eurographics Proceedings © 2016 The Eurographics Association.

关键词： Astrophysics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：