检索结果-内蒙古大学图书馆

Adaptive Resource Allocation algorithm of Lyapunov Optimization for Time-Varying Wireless Networks

IEEE COMMUNICATIONS LETTERS 2016年第5期20卷 934-937页

作者： Wu, Weihua Yang, Qinghai Li, Bingbing Kwak, Kyung Sup Xidian Univ Sch Telecommun Engn State Key Lab ISN Xian 710071 Peoples R China Xidian Univ Collaborat Innovat Ctr Informat Sensing & Underst Xian 710071 Peoples R China Inha Univ Grad Sch Informat Technol & Telecommun Inchon 402751 South Korea

In this letter, we investigate the adaptive resource allocation with Lyapunov optimization for time-varying wireless networks. The transmit power minimization is characterized by a stochastic optimization model. A dynamic resource allocation (DRA) algorithm is developed to accommodate the wireless network dynamics, i.e., time-varying wireless channels and as well the queuing dynamics. We investigate the tracking error between the DRA algorithm output and the target optimal resource allocation solution. Based on these results, we further develop an adaptive-compensation resource allocation (ACRA) algorithm, which iterates only once when the network state changes for saving the huge iteration overheads. Finally, we determine a sufficient condition that the ACRA algorithm asymptotically tracks the moving equilibrium point with no tracking errors. Simulation results validate the theoretical analysis of our proposed scheme.

关键词： iteration algorithm continuous-time Lyapunov optimization resource allocation

来源：评论

学校读者我要写书评

暂无评论

Absolute peak-efficiency calibration of a well-type germanium detector using multiple gamma-emitting nuclides with the "Solver" add-in in Excel™

引用

APPLIED RADIATION AND ISOTOPES 2017年 126卷 158-161页

作者： Ishizu, H. Yamada, T. Japan Radioisotope Assoc Bunkyo Ku 28-45Honkomagome 2 Tokyo 1138941 Japan

When calibrating absolute peak efficiency and total efficiency functions for high efficient germanium detectors, single gamma-emitting nuclides are used in general to avoid coincidence summing effects. As another approach, Blaauw developed calibration technique using multiple gamma-emitting nuclides with least-square technique (Blaauw, 1993;Blaauw and Gelsema, 2003). In the present study, we tried to calibrate efficiency functions of a well-type germanium detector based on Blaauw's approach using a home-made iteration calculation algorithm with the "Solver" add-in in Excel (TM).

关键词： Coincidence summing Germanium detector Peak efficiency iteration algorithm The "Solver" add-in in Excel (TM) Se-75 Cs-134

来源：评论

学校读者我要写书评

暂无评论

Cylindrical indentation of orthotropic laminates on elastic foundations

引用

JOURNAL OF COMPOSITES TECHNOLOGY & RESEARCH 2000年第3期22卷 127-135页

作者： Chen, CF Chung Hua Univ Inst Mech & Aerosp Engn Hsinchu 30067 Taiwan

Problems of cylindrical indentation of orthotropic laminated beams on an elastic foundation are studied. Exact solution methods are developed to assess the displacement field for both the simply supported and clamped-ended cases. A numerical iteration algorithm is established to detect the contact length and the associated contact stresses for a prescribed contact load. The induced interlaminar shear stresses through the thickness and the amount of indentation are evaluated subsequently. The objective is to investigate the effects of span, indentor size, end support conditions, and foundation stiffness on the local field responses and load-indentation relationships. The results show that the effects of indentor size and foundation stiffness are significant. A sharp indentor or stiff foundation tends to localize the contact phenomenon, regardless of the span and the end support conditions. On the other hand, the effects of both the boundary condition and span may be prominent if a blunt indentor and a relatively soft foundation are employed.

关键词： cylindrical indentation iteration algorithm interlaminar stresses non-Hertzian behavior

来源：评论

学校读者我要写书评

暂无评论

Minimum risk probability for finite horizon semi-Markov decision processes

引用

JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS 2013年第1期402卷 378-391页

作者： Huang, Yonghui Guo, Xianping Li, Zhongfei Sun Yat Sen Univ Sch Math & Computat Sci Guangzhou 510275 Guangdong Peoples R China Sun Yat Sen Univ Sch Business Guangzhou 510275 Guangdong Peoples R China

This paper studies the risk probability criteria for finite horizon semi-Markov decision processes. The goal is to find an optimal policy with the minimum risk probability that the total reward produced by a system during a finite horizon does not exceed a reward level, where the optimality is over the class of all randomized historic policies which include states, planning horizons and also reward levels. Under mild conditions, the optimality equation and the existence of optimal policies are established, and in addition, an iteration algorithm for solving optimal policies is developed. Our main results are applied to a manufacturing system. (C) 2013 Elsevier Inc. All rights reserved.

关键词： Finite horizon semi-Markov decision processes Risk probability Optimal value function iteration algorithm Optimal policy

来源：评论

学校读者我要写书评

暂无评论

Iterative second-order optical eigenmode imaging

引用

LASER PHYSICS LETTERS 2016年第1期13卷 015003-015003页

作者： Zhang, Suzhen Wang, Wei Yu, Rong Yang, Xiaoxue Huazhong Univ Sci & Technol Natl Lab Optoelect & Sch Phys Wuhan 430074 Peoples R China Dezhou Univ Coll Phys & Elect Informat Dezhou 253023 Peoples R China Wuhan Inst Technol Hubei Prov Key Lab Intelligent Robot Sch Sci Wuhan 430073 Peoples R China

Optical eigenmode imaging (OEI) reconstructs a complex object by using the orthogonality of optical eigenmodes. The image quality of OEI is limited by the missing of high-order eigenmodes. Here, we propose a universal method to improve the image quality of OEI by applying the iterative operation on the image collected by the second-order OEI (SOEI). The numerical simulations show that both the detrimental side bands and the position dependence of the point spread function by using OEI are largely mitigated.

关键词： optical eigenmode imaging ghost imaging iteration algorithm second order imaging

来源：评论

学校读者我要写书评

暂无评论

Hybrid method for accurate phase retrieval based on higher order transport of intensity equation and multiplane iteration

引用

OPTICAL ENGINEERING 2019年第6期58卷 063106-063106页

作者： Hu, Junbao Wu, Lingfeng Chinese Acad Sci Shanghai Inst Opt & Fine Mech Key Lab High Power Laser & Phys Shanghai Peoples R China Univ Chinese Acad Sci Beijing Peoples R China Jiangnan Univ Sch Sci Computat Opt Lab Wuxi Jiangsu Peoples R China Xian Univ Posts & Telecommun Ctr Image & Informat Proc Xian Shaanxi Peoples R China

Because phase contains specific information of the sample, especially transparent specimens such as biological cells and tissues, it is of utmost significance to accurately extract the phase. Although the phase can be directly solved from multiplane intensities through the prevalent transport of intensity equation (TIE) method, too many approximations in the solving process ultimately reduce its recovery accuracy. In addition, an iterative idea as a classic but potential tool allows quantitatively reconstructing phase while it is prone to trap in local stagnation due to nonconvexity. In order to restore the phase quantitatively and precisely, we propose a hybrid method combining the initial phase value via higher order TIE for system error reduction, and a final recovery solution using multiplane iteration for phase accuracy enhancement. Simulation and experimental results show that the proposed method not only has good noise suppression ability but also high phase recovery accuracy, and thus can be used in fields such as biological observation and medical diagnosis in the future. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： phase retrieval iteration algorithm transport of intensity equation

来源：评论

学校读者我要写书评

暂无评论

Convergence theorems of fixed points for Lipschitz pseudo-contractions in Hilbert spaces

引用

JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS 2008年第1期343卷 546-556页

作者： Zhou, Haiyun N China Elect Power Univ Inst Nonlinear Anal Baoding 071003 Peoples R China

Let C be a closed convex subset of a real Hilbert space H and assume that T is a k-strict pseudo-contraction on C. Consider Mann's iteration algorithm given by for all x(0) is an element of C, x(n+1) = alpha(n)x(n) + (1 - alpha(n))Tx(n), n >= 0. It is proved that if the control sequence {alpha(n)} is chosen so that k < alpha(n) < 1 and Sigma(infinity)(n=0)(alpha(n) - k) (1 - alpha(n)) = infinity, then lim(n ->infinity) vertical bar vertical bar x(n) - Tx(n) vertical bar vertical bar = d(0, ($$$) over barR(A)), where A = I - T and d(0,D) denotes the distance between the origin and the subset set D of H. As a consequence of this result, we prove that if T has a fixed point in C, then {x(n)} converges weakly to a fixed point of T. Also, we extend a result due to Reich to kappa-strict pseudo-contractions in the Hilbert space setting. Further, by virtue of hybridization projections, we establish a strong convergence theorem for Lipschitz pseudo-contractions. The results presented in this paper improve or extend the corresponding results of Browder and Petryshyn [F.E. Browder, W.V. Petryshyn, Construction of fixed points of nonlinear mappings in Hilbert spaces, J. Math. Anal. Appl. 20 (1967) 197-228], Rhoades [B.E. Rhoades, Fixed point iterations using infinite matrices, Trans. Amer. Math. Soc. 196 (1974) 162-176] and of Marino and Xu [G. Marino, H.-K. Xu, Weak and strong convergence theorems for strict pseudo-contractions in Hilbert spaces, J. Math. Anal. Appl. 329 (1) (2007) 336-346]. (C) 2008 Elsevier Inc. All rights reserved.

关键词： Lipschitz pseudo-contraction iteration algorithm convergence theorem

来源：评论

学校读者我要写书评

暂无评论

A procedure for transforming impedance spectra for the determination of mechanism of electrochemical reactions

引用

RUSSIAN JOURNAL OF ELECTROCHEMISTRY 2004年第11期40卷 1223-1226页

作者： Prilezhaeva, IN Solov'ev, NP Khramushin, NI Russian Federat State Sci Ctr Inst Phys & Power Engn Obninsk 249033 Kaluga Oblast Russia

Transformation of impedance spectra into relaxation time spectra (RTS) is used for determining contributions of individual processes of the oxygen electroreduction reaction (OER) to the polarization resistance of the electrochemical cell. The transformation technique involves the solution of the convolution equation found with the aid of a modified Van Cittert iteration algorithm checked on model impedance spectra. The technique, when used to analyze impedance spectra of electrochemical cells air\Pt\YSZ\YSZ + Ptlair, shows that the conversion of a globular structure of the YSZ + Pt cermet layer to a columnar one is accompanied by a change of peak amplitudes in RTS. The revealed RTS dynamics when heated to 750degreesC is compared with peculiarities of individual processes in OER.

关键词： solid-oxide fuel cells polarization resistance electrical double layer electrochemical reaction convolution equation iteration algorithm cermet coatings

来源：评论

学校读者我要写书评

暂无评论

Research on the variable static pressure control used iterative algorithm in a VAV system

Research on the variable static pressure control used iterat...

引用

4th International Conference on Technology of Architecture and Structure (ICTAS 2011)

作者： Jiang, Hongmei Ren, Qingchang Bai, Yan Xian Univ Architecture & Technol Sch Civil Engn Xian 710055 Peoples R China

ISBN: (纸本)9783037852798

In a VAV system the static pressure can be reseted based on the change of load. At low load conditions the duct static pressure can be adjusted lower, that make VAV terminal air valves in large opening as far as possible. And lower fan outlet pressure can effectively reduce fan energy consumption. This paper presents a method using iterative algorithm to control the fan frequency. It can improve the dynamic quality of the control system. Satisfying the requirements under lower static pressure so as to achieve the purpose of energy-saving.

关键词： VAV system iteration algorithm Variable static pressure Control Energy-saving

来源：评论

学校读者我要写书评

暂无评论

Enhanced optical image verification based on modified joint transform correlator architectures

Enhanced optical image verification based on modified joint ...

引用

Conference on Optical Information Systems

作者： Chang, HT Chen, CT Natl Yunlin Univ Sci & Technol Photon & Informat Lab Dept Elect Engn Touliu 64045 Taiwan

ISBN: (纸本)0819450758

In this paper two architectures for optical image verification are proposed. Both architectures are modified from conventional joint transform correlators (JTCs) and can significantly improve the recovered image quality. First, an input phase-only function is Fourier transformed and then is interfered with a reference wave that is diffracted from a plane wave incident on another random phase mask. Second, two phase-only functions are placed at the two input sides of a beam splitter such that the interference pattern of their Fourier transforms can be detected. The intensity of the interference pattern in both architectures can be recorded and then its Fourier-transform can be obtained in the output plane. To obtain a predefined target image in the output plane, the input phase function is iteratively retrieved by the use of the projection onto constraint sets algorithm. Simulation results show that the less mean squared error and better image quality are obtained for both the binary and grayscale images.

关键词： optical security joint transform correlator image verification phase retrieval iteration algorithm

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：