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Asymmetric-image verification for security optical systems based on joint transform correlator architecture

OPTICS COMMUNICATIONS 2004年第1-3期239卷 43-54页

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

In this paper, an optical asymmetric-image verification system based on the joint transform correlator architecture is proposed. An additional phase mask is attached to the spatial light modulator that displays the joint power spectrum as the amplitude information, to improve the system security and also enable the reconstruction of an asymmetric image. Two phase-only functions as keys are paired and iteratively retrieved by the use of the projection onto constraint sets and the multiple phase retrieval algorithms. In addition to the capability of reconstructing asymmetric images, the proposed architecture can also yield the better image quality for symmetric images. Simulation results are given to verify the proposed method and the dominant effects of two phase keys are discussed. (C) 2004 Elsevier B.V. All rights reserved.

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

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Characterisation, analysis and injection of two-tone third-order intermodulation products in an amplifier

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IET MICROWAVES ANTENNAS & PROPAGATION 2009年第3期3卷 443-455页

作者： Xiao, M. Gardner, P. Univ Birmingham Elect Elect & Comp Engn Dept Birmingham B15 2TT W Midlands England

A new mathematical description of the relationship between injected and output third-order intermodulation (IM3), to predict the injection signals required for predistortion correction of a power amplifier (PA), without manual optimisation is presented. A new concept of interactions and an iteration algorithm are also presented in order to improve this technique. The method is demonstrated with a commercial 2 GHz PA driven hard in a two-tone test with a range of input power and tone-spacing. The measurement results show that IM3 in a two-tone test can be suppressed by at least 60 dB, when the interactions between the upper and lower IM3 generation and the correction process are properly accounted for. The technique can deal with memory effects by cancelling unequal upper and lower sidebands.

关键词： iterative methods frequency 2 GHz Interpolation and function approximation (numerical analysis) Modulation and coding methods Amplifiers power amplifiers mathematical description power amplifier intermodulation injected and output third-order intermodulation iteration algorithm predistortion correction

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CALCULATION OF PRESSURE-DROP IN GAS AND GAS-CONDENSATE WELLS

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ENERGY SOURCES 1993年第1期15卷 125-133页

作者： ABBASOV, ZY Institute of Deep Oil and Gas Deposits Problems Azerbaijan Academy of Sciences Azizbekov prospect 33 Baku The Republic of Azerbaijan

The main principles of formation of static pressure in gas and gas-condensate wells, in which distribution of content and properties of phases with depth was taken into consideration, have been studied. An analytical basis and methods of calculation of formation pressure in gas and gas-condensate wells have been developed. Computer programs for studying the distribution of static pressure in wells with depth have also been developed.

关键词： CALCULATION EQUATION OF STATE GAS-CONDENSATE MIXTURE iteration algorithm NATURAL GAS PRESSURE DROP RECURRENT RATIO

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A new insight into the analysis of plane elasticity with coupling of numerical manifold and boundary element methods

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ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS 2021年 133卷 376-384页

作者： Dehghanzadeh-Najmabad, H. Hamzehei-Javaran, S. Ghasemzadeh, H. Karbakhsh, A. Islamic Azad Univ Dept Civil Engn Sirjan Branch Sirjan Iran Shahid Bahonar Univ Kerman Civil Engn Dept Kerman *** Iran KN Toosi Univ Technol Civil Engn Fac Tehran Iran

In this research, a combination of the numerical manifold method (NMM) and boundary element method (BEM) is presented for solving plane elasticity problems to benefit from the advantages of both methods. For this goal, the domain of the problems is divided into two regions, each region is analyzed separately, and finally, equilibrium and compatibility conditions are controlled in the interface by the iteration method. 1D quadratic boundary elements and 2D quadratic, cubic and quartic ones in the form of triangular shapes are utilized in the boundary element and manifold methods, respectively. The proposed method is verified by calculating the displacements and stresses resulting from the application of static loads in five different numerical problems. Comparison of the numerical results shows that the suggested method is very efficient and accurate.

关键词： Hybrid NMM-BEM Elastostatic problems Boundary element method Numerical manifold method iteration algorithm

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The spectral-Galerkin approximation of nonlinear eigenvalue problems

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APPLIED NUMERICAL MATHEMATICS 2018年 131卷 1-15页

作者： An, Jing Shen, Jie Zhang, Zhimin Beijing Computat Sci Res Ctr Beijing 100193 Peoples R China Guizhou Normal Univ Sch Math Sci Guiyang 550025 Guizhou Peoples R China Xiamen Univ Fujian Prov Key Lab Math Modeling & High Performa Xiamen 361005 Peoples R China Xiamen Univ Sch Math Sci Xiamen 361005 Peoples R China Purdue Univ Dept Math W Lafayette IN 47907 USA Wayne State Univ Dept Math Detroit MI 48202 USA

In this paper we present and analyze a polynomial spectral-Galerkin method for nonlinear elliptic eigenvalue problems of the form -div(A del u) + Vu + f(u(2))u = lambda u, parallel to u parallel to(L2) = 1. We estimate errors of numerical eigenvalues and eigenfunctions. Spectral accuracy is proved under rectangular meshes and certain conditions of f. In addition, we establish optimal error estimation of eigenvalues in some hypothetical conditions. Then we propose a simple iteration scheme to solve the underlying an eigenvalue problem. Finally, we provide some numerical experiments to show the validity of the algorithm and the correctness of the theoretical results. (C) 2018 IMACS. Published by Elsevier B.V. All rights reserved.

关键词： Spectral-Galerkin approximation Error estimation iteration algorithm Nonlinear eigenvalue problems

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Mechanical Performance of a Cascaded V-shaped Electrothermal Actuator

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INTERNATIONAL JOURNAL OF ADVANCED ROBOTIC SYSTEMS 2013年第11期10卷

作者： Shen, Xuejin Chen, Xiangyu Shanghai Univ Dept Mech Automat Engn Shanghai Peoples R China Univ Illinois Dept Elect & Comp Engn Urbana IL USA

The function and performance of MEMS are affected by the output ability of the displacement and force of microactuators. The lateral deflection of cascaded V-shaped electrothermal actuators is modelled as a triple, statically indeterminate problem. An iteration algorithm is set up to calculate the output displacement and typical forces in anchors. The calculated results of this model agree well with our own simulation results as well as with the experimental and calculated results in the literature, and we conclude that the model is credible. The paper also discusses the effects of the structure parameters and temperature increments on the displacement production ability. Clear differences were found between single and cascaded V-shaped electrothermal actuators. For the former, the maximum deflection takes place in a 0.04 rad beam angle, while for the latter the beam angle is 0.19 rad. For both types of actuators, the deflection is unrelated to the beam thickness. The displacement of the cascaded V-shaped electrothermal actuator is proportional to the temperature increment and beam length, but is inversely proportional to the beam width. Experiments on the output ability of cascaded V-shaped electrothermal actuators validated the calculated and simulation results.

关键词： MEMS Electrothermal Actuators Mechanics Model iteration algorithm Performance Analysis

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Referral Strategy Based on Social Network Incentive

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IEEE TRANSACTIONS ON COMPUTATIONAL SOCIAL SYSTEMS 2024年第1期11卷 683-696页

作者： Li, Yongli Liu, Chao Wei, Chuang Ma, Xiaochen Harbin Inst Technol Sch Econ & Management Harbin 150001 Peoples R China Cent Univ Finance & Econ Business Sch Beijing 100081 Peoples R China

Customers' social network is often regarded as valuable capital for companies and individuals. Although quite a few studies have empirically demonstrated the positive influence of customers' social networks on boosting sale performance, it is still an open question that how to utilize customers' social networks to design profitable and feasible referral incentive strategies. To this end, this work establishes a game model by introducing the referral incentive strategies of different forms based on the analysis of the marketing process. Regarding the modeled incentive strategy as the target of solving the game model, this work finds it is an NP-hard problem of solving the model and further proposes an approximate algorithm. In order to cope with large-scale data sets, the proposed algorithm is further extended into a new one with low time complexity. Then, theoretical analysis, numerical experiments, and real applications are conducted to validate the performance of the model. In all, the proposed model, algorithm, and findings contribute to both theoretic models and practical operations in the field of social networks and social computation.

关键词： Social networking (online) Games Costs Time complexity Solid modeling Approximation algorithms Analytical models iteration algorithm network incentive referral strategy social marketing social network

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Serial Production Lines With Waiting Time Limits: Bernoulli Reliability Model

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IEEE TRANSACTIONS ON ENGINEERING MANAGEMENT 2018年第2期65卷 316-329页

作者： Lee, Jun-Ho Li, Jingshan Horst, John A. Konkuk Univ Sch Business Seoul 05029 South Korea Univ Wisconsin Dept Ind & Syst Engn Madison WI 53706 USA NIST Engn Lab Gaithersburg MD 20899 USA

Production systems with waiting time constraints are frequently encountered in semiconductor, automotive, battery, food, and many other manufacturing industries. Under the waiting time constraints, the residence time of in-process inventories is constrained by a predetermined time limit. A part exceeding the maximal time limit has to be inspected for quality assurance and it is subject to be scrapped with a certain probability. In this paper, performance evaluation of Bernoulli serial lines with waiting time limits is studied. Analytical formulas are derived to predict the system performance of two-machine lines in steady state. For longer lines, direct analysis is no longer viable due to high complexity, thus an aggregation-based iterative procedure is introduced. Based on extensive numerical studies, the convergence of the procedure can be observed and high accuracy in performance estimation is achieved. In addition, to design such lines, an efficient procedure for near optimal buffer assignment to maximize production rate is also proposed. Analogously, we first propose an exact algorithm for two-machine lines and then extend it to a recursive procedure for longer lines. We then numerically verify that the procedure provides a near optimal solution within a very short computation time. Finally, the impacts of relaxing waiting time constraints on line performance and buffer design are discussed, and operational strategies to achieve better performance are also presented.

关键词： Bernoulli machine buffer design iteration algorithm performance evaluation waiting time constraint

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A particle swarm optimization and coupled generalized differential quadrature element methods with genetic algorithm for stability analysis of the laminated microsystems

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ENGINEERING WITH COMPUTERS 2022年第SUPPL 4期38卷 3251-3268页

作者： Sun, Hua Shandong Univ Arts Lib Jinan 250014 Shandong Peoples R China

In this paper, an attempt is made to extend a linear two-dimensional model for stability analysis of the laminated annular microplate subject to external excitation. A new approach called hybrid optimization is introduced to solve optimization problems with a high sensitive objective function to decline computational costs and increase the predicted optimum results accuracy. Regarding this issue, generalized differential quadrature element method (GDQEM), particle swarm optimization (PSO), as well as genetic algorithm (GA) methods are coupled to improve the dynamic stability of the annular microsystems via finding an optimum frequency and fiber angle of layers simultaneously. Higher-order shear deformation theory (HSDT) and Hamilton's principle are taken into consideration for the exact derivation of the general linear governing equations and boundary conditions of the axisymmetric laminated annular plate. Also, modified couple stress theory (MCST) is presented for presenting the size-dependency of the current microsystem. The GDQEM is used to solve the governing equations of the microsystem via its boundary domains. To enhance the genetic algorithms' performance for solving equations, the optimizer approach of particle swarm has been employed as a GA's operator. Precise convergence and practicality of the suggested mixed-method have been disclosed. Moreover, we would have proven that for achieving the convergence PSO's and GA's outcomes, we have to apply higher than fifteen iterations.

关键词： iteration algorithm Particle swarm optimization Higher-order shear deformation theory Annular microsystem Genetic algorithm Frequency

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An improved transmitter system to accurately measure wet-bulb temperature of air

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MEASUREMENT & CONTROL 2019年第7-8期52卷 1002-1007页

作者： Yan, Liangwen Yu, Peng Hu, Sijung Gao, Qiu Li, Wei Qian, Fengfeng Shanghai Univ Sch Mechatron Engn & Automat Shanghai Peoples R China Loughborough Univ Wolfson Sch Mech Elect & Mfg Engn Ashby Rd Loughborough LE11 3TU Leics England

A cost-effective measurement of wet-bulb temperature of air has great benefits to fulfill a growing demand of industry, cultivation agriculture, and medication. Applying an appropriate algorithm to wet-bulb temperature of air measurement can effectively improve the accuracy and speed of its measurement. The study aims to research how an improved transmitter system along with the latent heat-based iteration algorithm is used to precisely measure wet-bulb temperature of air. The work consists of (1) simulation of the iteration algorithm and (2) validation via experimental protocol. The simulation results through latent heat-based iteration algorithm were in good agreement (R-2 >= 0.99) with the reference. The performance of the improved wet-bulb temperature of air transmitter system was tested by a latent heat-based iteration algorithm experimental setup. The experimental results demonstrate that the improved wet-bulb temperature of air in a good consistency with commercial wet-bulb temperature of air in a range of temperature (15 degrees C-34 degrees C) and relative humidity (28.8%-76.2%). The Bland-Altman plot also shows that the mean value and the standard deviation of the differences between these two systems are 0.14 degrees C and 0.29 degrees C, respectively, which indicates that the improved wet-bulb temperature of air has a good agreement as well. Compared with the commercial wet-bulb temperature of air transmitter system, an advanced processor (STM32F103C8T6) and real-time operating system was applied in the improved wet-bulb temperature of air transmitter system. The experimental results show that its measurement accuracy is closer to the previous study. This study provides an alternative and cost-effective solution to accurately and real-time measure wet-bulb temperature of air.

关键词： Wet-bulb temperature of air transmitter system relative humidity iteration algorithm

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