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Energy efficiency maximisation in downlink multi-cell networks via coordinated resource allocation

IET COMMUNICATIONS 2015年第1期9卷 42-54页

作者： Tong, Zhao Li, Bingbing Hui, Yongtao Xidian Univ State Key Lab Integrated Serv Networks Xian 710071 Peoples R China

There is a great interest in considering the energy efficiency (EE) as an important performance evaluation recently for its contribution to both energy saving and environmental conservation. In this study, the authors focus on the optimal energy-efficient design for downlink multi-cell environment with coordinated scheduling and beamforming. The EE is defined as bit-per-joule capacity to indicate how efficiently energy is consumed for transmitting information. They set up the optimum model for maximising the EE of coordinated cells subject to a total power constraint at each base station and study the resource allocation (RA) for it, including user selection, power allocation and beamforming vectors optimisation. They consider an equivalent non-fractional form of the original problem and propose an iterative algorithm to optimise the spectrum RA and beamforming vectors alternatively. In each iteration, the beamforming vectors are updated by the iterative algorithm based on the first-order optimality conditions, while the user scheduling policy is updated by the enhanced greedy algorithm. Performance studies show that the proposed algorithm has a rapid speed of convergence and achieves significant performance gain in EE for cellular networks.

关键词： cellular radio energy conservation resource allocation array signal processing iterative methods cellular networks beamforming vectors iterative algorithm beamforming vectors optimisation power allocation bit-per-joule capacity coordinated scheduling downlink multicell environment environmental conservation energy saving performance evaluation coordinated resource allocation downlink multicell networks energy efficiency maximisation

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An Instrumental Variable Approach for the Identification of Time-Varying, Hammerstein Systems

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IFAC-PapersOnLine 2015年第28期48卷 196-201页

作者： Guarin, Diego L. Kearney, Robert E. Department of Biomedical Engineering Faculty of Medicine McGill University 3775 University St room 316 Canada

This paper introduces an iterative algorithm for the identification of time-varying (TV)-Hammerstein systems. This system is composed by a TV static nonlinearity followed by a TV Box-Jenkins linear model. The algorithm uses two basis function expansions: one to represent the TV parameters and a second to approximate the output of the static nonlinearity. A simulation study showed that the algorithm accurately identified the shape of the TV static nonlinearity and linear dynamic elements even though the noise model structure was unknown. © 2015

关键词： Control nonlinearities Functions Identification (control systems) iterative methods Nonlinear systems Basis functions Hammerstein system Instrumental variables iterative algorithm Nonlinear systems identification Prediction error method Simulation studies Static non linearity

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Explicit iterations and extremal solutions for fractional differential equations with nonlinear integral boundary conditions

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APPLIED MATHEMATICS AND COMPUTATION 2015年 268卷 388-392页

作者： Zhang, Lihong Ahmad, Bashir Wang, Guotao Shanxi Normal Univ Sch Math & Comp Sci Linfen 041004 Shanxi Peoples R China King Abdulaziz Univ Fac Sci Dept Math Jeddah 21589 Saudi Arabia

This paper studies the existence of extremal solutions for nonlinear fractional differential equations with nonlinear integral boundary conditions and explores an explicit algorithm which converges to the extremal solutions of the problem at hand. An example is discussed for the illustration of the main work. (C) 2015 Elsevier Inc. All rights reserved.

关键词： Extremal solutions Monotone sequence Fractional differential equations Nonlinear integral boundary conditions iterative algorithm

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Three kinds of new hybrid projection methods for a finite family of quasi-asymptotically pseudocontractive mappings in Hilbert spaces

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FIXED POINT THEORY AND APPLICATIONS 2015年第1期2015卷 1-13页

作者： Liu, Yuanxing Zheng, Liguo Wang, Peiyuan Zhou, Haiyun Hebei Univ Econ & Business Coll Math & Stat Shijiazhuang 050061 Peoples R China Langfang Normal Univ Dept Math & Informat Langfang 065000 Peoples R China Naval Equipment Inst Postdoctoral Workstn Beijing 102249 Peoples R China Naval Aviat Inst Huludao 125001 Peoples R China Shijiazhuang Mech Engn Coll Dept Math Shijiazhuang 050003 Peoples R China

In the present paper, we propose three kinds of new algorithms for a finite family of quasi-asymptotically pseudocontractive mappings in real Hilbert spaces. By using some new analysis techniques, we prove the strong convergence of the proposed algorithms. Some numerical examples are also included to illustrate the effectiveness of the proposed algorithms. The results presented in this paper are interesting extensions of those well-known results.

关键词： a finite family of quasi-asymptotically pseudocontractive mapping uniformly L-Lipschitz mapping iterative algorithm strong convergence Hilbert space

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Identification of Polynomial Wiener Systems via Volterra-Laguerre Series with Model Mismatch

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IFAC-PapersOnLine 2015年第11 11期48卷 831-836页

作者： Jansson, Daniel Medvedev, Alexander Department of Information Technology Uppsala University Uppsala Sweden

This paper considers the effects due to model mismatch in system identification of discrete polynomial Wiener systems via Volterra-Laguerre series. A special case of third-order polynomial nonlinearities and Gaussian input signals is treated in detail though the approach appears to be valid for a more general problem formulation. Expressions for the bias in the estimates of the model coeficients due to a linear block model mismatch are derived and an iterative algorithm for reducing the bias value is proposed. The analytical results are illustrated by numerical experiments confirming the eficacy of the bias reduction algorithm. © 2015

关键词： Polynomials iterative methods Nonlinear systems Religious buildings Analytical results Bias reduction Discrete polynomials iterative algorithm Numerical experiments Problem formulation Volterra Series Wiener systems

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A novel approach to decision support and optimization of group job handling for multimodal processes in manufacturing and services

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IFAC-PapersOnLine 2015年第3期28卷 2115-2120页

作者： Sitek, P. Wikarek, J. Department of Control and Management Systems Kielce University of Technology Poland

This study deals with decision support system and optimization of parallel handling of groups of jobs. All jobs in a group should be delivered at the same time after processing. The authors present a novel hybrid approach, which includes the modelling of the problem in the integrated environment, composed of MP (Mathematical Programming) and CLP (Constraint Logic Programming). In addition to the iterative algorithm for solving the hybrid model under dynamic emergence of new orders, the paper proposes the transformation and linearization of the model in CLP/MP environment. Opportunity to ask questions and receive quick answers, taking into account any constraints, conditions and dynamics, constitutes an invaluable support to the manager. The paper proposes new CLP-based functionalities and an illustrative example with the model for service providers (a restaurant). © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Decision support systems Artificial intelligence Computer circuits Computer programming languages iterative methods Logic programming Manufacture Mathematical programming Optimization Constraint Logic Programming Decision supports Dynamic emergence Group processing Integrated environment iterative algorithm Multi modal Service provider

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Data-driven portfolio management with quantile constraints

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OR SPECTRUM 2015年第3期37卷 761-786页

作者： Cetinkaya, Elcin Thiele, Aurelie Amazon Com Seattle WA USA Lehigh Univ Dept Ind & Syst Engn Bethlehem PA 18015 USA

We investigate an iterative, data-driven approximation to a problem where the investor seeks to maximize the expected return of her portfolio subject to a quantile constraint, given historical realizations of the stock returns. The approach, which was developed independently from Calafiore (SIAM J Optim 20:3427-3464 2010) but uses a similar idea, involves solving a series of linear programming problems and thus can be solved quickly for problems of large scale. We compare its performance to that of methods commonly used in the finance literature, such as fitting a Gaussian distribution to the returns (Keisler, Decision Anal 1:177-189 2004;Rachev et al. Advanced stochastic models, risk assessment and portfolio optimization: the ideal risk, uncertainty and performance measures, Wiley, New York 2008). We also analyze the resulting efficient frontier and extend our approach to the case where portfolio risk is measured by the inter-quartile range of its return. Our main contribution is in the detail of the implementation, i.e., the choice of the constraints to be generated in the master problem, as well as the numerical simulations and empirical tests, and the application to the inter-quartile range as a risk measure.

关键词： Data-driven optimization Quantile constraints iterative algorithm

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Experimental Evaluation of an iterative Reconstruction Method for Time-Correlation Magnetic Particle Imaging

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IEEE TRANSACTIONS ON MAGNETICS 2015年第2期51卷 1-4页

作者： Tsuchiya, Hiroki Homma, Takumi Shimizu, Shota Ishihara, Yasutoshi Meiji Univ Sch Sci & Technol Kawasaki Kanagawa 2148571 Japan Meiji Univ Grad Sch Sci & Technol Kawasaki Kanagawa 2148571 Japan

We have previously proposed an image reconstruction method to improve the image resolution in magnetic particle imaging. In that method, the image is reconstructed based on time-correlation information between the observed signal from magnetic nanoparticles and the corresponding system function. However, image blurring and image artifacts were not sufficiently improved under this method. Therefore, we proposed a new iterative image reconstruction method, in which the reconstructed image is iteratively estimated by correcting the difference between the analytically calculated signals from the reconstructed images and the observed signals during iteration. In this paper, to confirm the validity of this new proposed method, we performed experiments using the 3-D prototype system and numerical simulations based on the prototype system setup. The results achieved by the prototype system experiments showed that the image blurring was suppressed and the image quality improved as compared with the previous time-correlation reconstruction method.

关键词： Image reconstruction iterative algorithm magnetic particle imaging (MPI) prototype system

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Neural network segmented CD algorithm-based PET liver image reconstruction

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INTERNATIONAL JOURNAL OF BIOMEDICAL ENGINEERING AND TECHNOLOGY 2015年第3期17卷 276-289页

作者： Prasath, T. Arun Rajasekaran, M. Pallikonda Kannan, S. Kalasalingam Univ Dept Instrumentat & Control Engn Krishnankoil 626126 Tamil Nadu India Kalasalingam Univ Dept Elect & Commun Engn Krishnankoil 626126 Tamil Nadu India Ramco Inst Technol Dept Elect & Elect Engn Rajapalayam 626117 Tamil Nadu India

In this paper, reconstruction of the Positron Emission Tomography (PET) images, a CD algorithm was instigated with NN based image segmentation techniques called Neural Network Segmentation based Coordinate DescentWeighted Least Square (NNCD-WLS). Thus, NNCD-WLS of the function is not quadratic, but natural. The iterative algorithm achieve a fashion equivalent to an analytic derivation of the Maximum Likelihood-Expectation Maximisation (ML-EM) algorithm, which gives a different minimisation process between two convex sets of matrices. Conversely the distance metric is quite distinct, and more intricate to analyse. This algorithm is similar type, shares many properties acquainted with the ML-EM algorithm. Unlike WLS algorithm, NNCD-WLS method minimises the WLS objective function. The NNCD-WLS algorithm instigates via NN based segmentation process in image reconstruction. Image quality parameter of the PSNR value, NNCD-WLS algorithm and the denoising algorithm is compared. The PET input image is reconstructed and simulated in the MATLAB/Simulink package.

关键词： PET liver image positron emission tomography image reconstruction neural network segmentation WLS weighted least squares CD coordinate descent iterative algorithm EM expectation-maximisation algorithm

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RERS2014 AND MRS2014: NEW HIGH-PRECISION RIGID EARTH ROTATION AND MOON ROTATION SERIES

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ARTIFICIAL SATELLITES-JOURNAL OF PLANETARY GEODESY 2015年第1期50卷 35-40页

作者： Pashkevich, V. V. RAS Cent Pulkovo Astron Observ Pulkovskoe Shosse 65-1 St Petersburg 196140 Russia

Numerical investigation of the Earth and Moon rotational motion dynamics is carried out at a long time intervals. In our previous studies (Pashkevich, 2013), (Pashkevich and Eroshkin, 2011) the high-precision Rigid Earth Rotation Series (designated RERS2013) and Moon Rotation Series (designated MRS2011) were constructed. RERS2013 are dynamically adequate to the JPL DE422/LE422 (Folkner, 2011) ephemeris over 2000 and 6000 years and include about 4113 periodical terms (without attempt to estimate new subdiurnal and diurnal periodical terms). MRS2011 are dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 418, 2000 and 6000 years and include about 1520 periodical terms. In present research have been improved the Rigid Earth Rotation Series RERS2013 and Moon Rotation Series MRS2011, and as a result have been constructed the new high-precision Rigid Earth Rotation Series RERS2014 and Moon Rotation Series MRS2014 dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years, respectively. The elaboration of RERS2013 is carried out by means recalculation of sub-diurnal and diurnal periodical terms. The residuals in Euler angles between the numerical solution and RERS2014 do not surpass 3 mu as over 2000 years. Improve the accuracy of the series MRS2011 is obtained by using the JPL DE422/LE422 ephemeris. The residuals in the perturbing terms of the physical librations between the numerical solution and MRS2014 do not surpass 8 arc seconds over 6000 years

关键词： the rigid Earth rotation the Moon rotation ephemeris iterative algorithm least-squares method spectral analysis method

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