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28th AIAA/CEAS Aeroacoustics Conference

作者： Fischer, J. Doolan, C. Croaker, P. Howell, R. Dylejko, P. Univ New South Wales Sch Mfg & Mech Engn Sydney NSW 2052 Australia Def Sci & Technol Grp Maritime Div Sydney NSW 2015 Australia Def Sci & Technol Grp Maritime Div Melbourne Vic 3207 Australia YTEK Pty Ltd Level 1231 High St Ashburton Vic 3147 Australia

ISBN: (数字)9781624106644

ISBN: (纸本)9781624106644

This paper presents a new semi-empirical model for predicting the far-field acoustic propagation for a ducted rotor. The model is based principally on the work of Stephens & Morris (Journal of Sound and Vibration, 313 (2008) 97-112) and Tomko et al. (Journal of Sound and Vibration 45 (2019) 84-98): the former uses experimental far-field acoustic data as an input to estimate the dipole source spectra from the rotor, and the latter calculates the pressure inside the duct using the estimated source spectra. The pressure at the duct exit is then propagated to the far-field using a Green's function formulation. The results from the model are first compared to the literature and show good agreement in recovering the dipole spectra. However, the transfer function between the source and the far-field pressure is not consistent due to the difference of configuration between the two experiments. When comparing the model output to the measured spectra, a good agreement is found especially at high rotating speeds where the signal-to-noise ratio is more important.

关键词： Ducted Propellers Bessel Functions Acoustic Propagation Blade Passing Frequency Strouhal Number Acoustic Measurement Polyvinyl Chloride Data Acquisition System iterative algorithm Mathematical Models

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PRIVACY PROTECTION IN LEARNING FAIR REPRESENTATIONS 47

PRIVACY PROTECTION IN LEARNING FAIR REPRESENTATIONS

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47th IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)

作者： Jin, Yulu Lai, Lifeng Univ Calif Davis Dept ECE Davis CA 95616 USA

ISBN: (纸本)9781665405409

In this paper, we develop a framework to achieve a desirable trade-off between fairness, inference accuracy and privacy protection in the inference as service scenario. Instead of sending raw data to the cloud, we conduct a random mapping of the data, which will increase privacy protection and mitigate bias but reduce inference accuracy. To properly address the trade-off, we formulate an optimization problem to find the optimal transformation map. As the problem is non-convex in general, we develop an iterative algorithm to find the desired map. Numerical examples show that the proposed method has better performance than gradient ascent in the convergence speed, solution quality and algorithm stability.

关键词： statistical inference fair representation privacy protection iterative algorithm

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Resource Management for Cooperative Service Offering with a Generalized Service-Centric Model

Resource Management for Cooperative Service Offering with a ...

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IEEE/CIC International Conference on Communications in China (ICCC)

作者： Wu, Xuan Huang, Yang Gao, Zhen Nanjing Univ Aeronaut & Astronaut Nanjing 210016 Peoples R China Southeast Univ Natl Mobile Commun Res Lab Nanjing Peoples R China Beijing Inst Technol Beijing Peoples R China

ISBN: (数字)9781665484800

ISBN: (纸本)9781665484800

The development of the Internet of Things (IoT) witnesses a growing number of intelligent services. Nevertheless, the IoT devices can suffer from limited energy supply and computing ability. Reminiscent of the concept of multi-access edge computing and ubiquitous computing, IoT devices can share the network resources and cooperate to offer intelligent services. Nevertheless, state-of-the-art models for resource optimization cannot fully characterize the requirement of services. Therefore, we propose a novel generalized service-centric model for resource allocation optimization in the presence of cooperative service offering. Based on the model, a joint network resource allocation and device scheduling optimization is investigated. This problem is shown to be a mixed integer non-linear programming (MINLP) problem. To solve the problem, alternating optimization is integrated with the Hungarian method, where the device scheduling optimization suffers from the cubic complexity. Simulation results illustrate that the proposed service-centric optimization model can significantly reduce the overall energy consumption, as well as the slope of average energy consumption in the presence of an increasing number of tasks.

关键词： Generalized service-centric optimization model resource allocation device scheduling iterative algorithm MINLP problem

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Reconstruction of Partially Occluded Facial Image for Classification

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IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING 2021年第4期16卷 600-608页

作者： Zou, Min You, Mengbo Akashi, Takuya Iwate Univ Grad Sch Engn Morioka Iwate 0208551 Japan Northwest A&F Univ Coll Informat Engn Yangling 712100 Shaanxi Peoples R China Iwate Univ Fac Sci & Engn Morioka Iwate 0208551 Japan

The recent literature indicates that face recognition and facial expression classification has achieved a high accuracy on benchmark datasets with a large number of face images in the wild. On the other hand, unlike the purpose of recognizing as many people as possible, real applications for families or companies usually aim to recognize a small group of people as accurate as possible. In case of the face is partially occluded, convolutional solutions always simply put images with occlusions into the training dataset and hope the convolution neural network learn a model robust to partial occlusion. These processes not only increase the burden of learning, but also affect the model to identify normal images without occlusions. In this paper, we investigate the research problem of facial image reconstruction to discard the influence of partial occlusion. Based on the phenomenon that human faces are roughly symmetrical, we propose to reconstruct the facial information of occluded areas with the intact half face. Specifically, occlusion on the left-half face is reconstructed with a linear combination of features on the right-half face and vice versa. The process is modeled by keeping row sparsity for the coefficient matrix with l(2,1)-norm regularization while minimizing the reconstruction error. An alternative iterative algorithm is proposed to solve the optimization problem. To validate the effectiveness of the reconstruction, we fine-tune a pretrained model, AlexNet, training on normal face images and test with various occluded images. Extensive experimental results show that our method has improved the classification performance effectively. (c) 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

关键词： face reconstruction partial occlusion iterative algorithm flipping strategy

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Kinematics Analysis of 3-RRPS Parallel Mechanism 19

Kinematics Analysis of 3-RRPS Parallel Mechanism

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19th IEEE International Conference on Mechatronics and Automation (IEEE ICMA)

作者： Yu, Cheng Li, Bin Zhu, Jiaqi Tianjin Univ Technol Sch Mech Engn Tianjin Key Lab Adv Mechatron Syst Design & Intel Tianjin 300384 Peoples R China Tianjin Univ Technol Natl Demonstrat Ctr Expt Mech & Elect Engn Educ Tianjin Peoples R China

ISBN: (数字)9781665408530

ISBN: (纸本)9781665408530;9781665408523

In this paper, the kinematics of the 3-RRPS parallel mechanism was deeply studied, and the kinematics mathematical model of the parallel mechanism was obtained by using the method of coordinate system transformation. The inverse solution of the parallel mechanism pose was obtained by solving this equation, and the nonlinear equation was obtained from the inverse solution. The forward solution of the attitude of the parallel mechanism was calculated by solving this nonlinear equation with Jacobian matrix and Newton iterative algorithm, which is an approximate solution. Finally, we verified the correctness of the forward kinematics solution through MATLAB.

关键词： Parallel mechanism 3-RRPS Inverse pose solution iterative algorithm Forward pose solution

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A Solution algorithm for a Modified Bouc-Wen Model Capable of Simulating Cyclic Softening and Pinching Phenomena 10

A Solution Algorithm for a Modified Bouc-Wen Model Capable o...

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10th Vienna International Conference on Mathematical Modelling (MATHMOD)

作者： Capuano, Raffaele Vaiana, Nicolo Pellecchia, Davide Rosati, Luciano Univ Naples Federico II Dept Struct Engn & Architecture Naples Italy

The paper illustrates an extension of a solution algorithm required to evaluate the output variable of a modified Bouc-Wen model, namely a differential model capable of simulating generalized force-displacement hysteresis loops exhibiting cyclic softening and/or pinching. The proposed solution scheme has been derived by adopting the Backward Euler Method in conjunction with the Newton-Raphson iterative procedure. In order to demonstrate the accuracy and the computational efficiency of the proposed algorithm, the results of numerical simulations are compared to those obtained by employing the widely used MATLAB ode45 solver. Copyright (C) 2022 The Authors.

关键词： Hysteresis Bouc-Wen model cyclic softening pinching iterative algorithm

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An Improved Equiangular Division algorithm for SBR based Ray Tracing Channel Modeling 96

An Improved Equiangular Division Algorithm for SBR based Ray...

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IEEE 96th Vehicular Technology Conference (VTC-Fall)

作者： Zhou, Yuyang Wang, Yinghua Li, Yuxiao Huang, Jialing Huang, Jie Wang, Cheng-Xiang Southeast Univ Sch Informat Sci & Engn Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China Purple Mt Labs Nanjing 211111 Peoples R China

ISBN: (纸本)9781665454681

Compared with image method (IM) based ray tracing (RT), shooting and bouncing ray (SBR) method is characterized by fast speed but low accuracy. In this paper, an iterative precise algorithm based on equiangular division is proposed to make rough paths accurate, allowing SBR to calculate exact channel information. Different ray launching methods are compared to obtain a better launching method. By using equiangular division, rays are launched more uniformly from transmitter (Tx) compared with the current equidistant division method. With the proposed iterative precise algorithm, error of angle of departure (AOD) and angle of arrival (AOA) is below 0.01 degrees. The relationship between the number of iterations and error reduction is also given. It is illustrated that the proposed method has the same accuracy as IM by comparing the power delay profile (PDP) and angle distribution of paths. This can solve the problem of low accuracy brought by SBR.

关键词： ray tracing shooting and bouncing ray method equiangular division iterative algorithm channel modeling

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Semi-Supervised Learning for MIMO Detection 14

Semi-Supervised Learning for MIMO Detection

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14th IEEE International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Ao, Peiyan Li, Runhua Sun, Rongchao Xue, Jiang Xi An Jiao Tong Univ Math & Stat Xian Peoples R China

ISBN: (纸本)9781665450850

The model-driven deep learning method has been verified to be effective for signal detection in the massive multi-input multi-output (MIMO) system. In previous work, this kind of methods need to be trained with numerous pilots in a supervised manner, which will occupy amount of spectrum resources. In addition, the abundant information in the symbols are not utilized in the training procedure. To solve this issue, Firstly in this paper, a new unsupervised deep learning (DL) network named Un-OAMPNet is proposed, which considers Mixture of Gaussian (MoG) noise model under a maximum a posterior (MAP) framework. Secondly, Un-OAMPNet is extended to the semi-supervised DL network (Semi-OAMPNet) with a few pilots to increase the detection performance. In Semi-OAMPNet, the loss function is combined with the mean square error (MSE) loss in the supervised manner and the MAP loss in the unsupervised manner. In this way, Semi-OAMPNet inherits the advantages of OAMP-Net2 and gains better detection performance with fewer pilots. Simulation results show that the Un-OAMPNet is effective without any pilots in the training procedure and proposed Semi-OAMPNet has better performance compared with other model-driven detectors.

关键词： Model-driven MIMO detection iterative algorithm noise model semi-supervised learning

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ACOUSTIC SYSTEM IDENTIFICATION WITH PARTIALLY TIME-VARYING MODELS BASED ON TENSOR DECOMPOSITIONS 17

ACOUSTIC SYSTEM IDENTIFICATION WITH PARTIALLY TIME-VARYING M...

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17th International Workshop on Acoustic Signal Enhancement (IWAENC)

作者： Huang, Gongping Benesty, Jacob Chen, Jingdong Paleologu, Constantin Ciochina, Silviu Kellermann, Walter Cohen, Israel Univ Erlangen Nurnberg LMS D-91058 Erlangen Germany Univ Quebec INRS EMT Montreal PQ H5A 1K6 Canada Northwestern Polytech Univ CIAIC Xian 710072 Shaanxi Peoples R China Univ Politehn Bucuresti Bucharest 061071 Romania Technion Israel Inst Technol IL-3200003 Haifa Israel

ISBN: (数字)9781665468671

ISBN: (纸本)9781665468671

Acoustic system identification, which aims at estimating the channel impulse response from a source of interest to the microphone position, plays an important role in many applications, e.g., echo cancellation for full-duplex speech communication. Generally, an acoustic channel impulse response is modeled as a linear finite-impulse-response (FIR) filter, so the objective of system identification is to identify it. While much effort has been devoted to this topic over the last five decades, identifying the room FIR filters accurately with only a small number of observation data snapshots remains a significant challenge. This paper studies this problem and proposes to model the acoustic impulse response, i.e., the FIR filter, with a tensor decomposition, which can be expressed as a multidimensional Kronecker product of a series of shorter filters. Then, a partially time-varying model is applied to acoustic system identification, where the global filter is decomposed into two parts: a time-invariant part, which captures the common properties of acoustic channels, and a time-varying part, which, as its name indicates, represents the components of acoustic channels that change with time. During the identification process, the time-invariant filters can be identified or learned in advance, while the time-varying filters are optimized through an iterative procedure. Simulation results demonstrate that the proposed technique can achieve better acoustic system identification performance with a small number of data snapshots.

关键词： Acoustic system identification Kronecker product decomposition tensor decomposition Wiener filter iterative algorithm

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Improvement of SPGD by Gradient Descent Optimization algorithm in Deep Learning

Improvement of SPGD by Gradient Descent Optimization Algorit...

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Asia Communications and Photonics Conference (ACP) / International Conference on Information Photonics and Optical Communications (IPOC)

作者： Zhao, Qingsong Hao, Shiqi Wang, Yong Wang, Lei Lin, Zhi Natl Univ Def Technol AnHui Prov Key Lab Elect Restrict Coll Elect Countermeasure Hefei Peoples R China

ISBN: (纸本)9781665481557

The distortion caused by atmospheric turbulence can be compensated by wavefront correction, which improves the performance of free space optical vortex beam communication. In order to solve the slow convergence problem of the traditional stochastic parallel gradient descent algorithm in wavefront correction, an iterative correction algorithm based on adaptive gain factor is presented, which is combined with the Adam optimization algorithm in deep learning. The simulation verifies that the algorithm is more robust in turbulent environment.

关键词： wavefront correction iterative algorithm atmospheric turbulence

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