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Chinese Journal of Mechanical Engineering 2020年第1期33卷 182-196页

作者： Fei shen chao Chen Jiawen Xu Ruqiang Yan School of Instrument Science and Engineering Southeast UniversityNanjing 210096China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Most gear fault diagnosis(GFD)approaches su er from ine ciency when facing with multiple varying working conditions at the same *** this paper,a non-negative matrix factorization(NMF)-theoretic co-clustering strategy is proposed specially to classify more than one task at the same time using the high dimension matrix,aiming to o er a fast multi-tasking *** short-time Fourier transform(STFT)is first used to obtain the time-frequency features from the gear vibration ***,the optimal clustering numbers are estimated using the Bayesian information criterion(BIC)theory,which possesses the simultaneous assessment capability,compared with traditional validity ***,the classical/modified NMF-based co-clustering methods are carried out to obtain the classification results in both row and column ***,the parameters involved in BIC and NMF algorithms are determined using the gradient ascent(GA)strategy in order to achieve reliable diagnostic *** Spectra Quest’s Drivetrain Dynamics Simulator gear data sets were analyzed to verify the e ectiveness of the proposed approach.

关键词： Gear fault diagnosis Non-negative matrix factorization Co-clustering Varying working conditions

Rectangle Attack Against Type-I Generalized Feistel Structures

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Chinese Journal of Electronics 2022年第4期31卷 713-720页

作者： ZHANG Yi LIU Guoqiang shen Xuan LI chao College of Liberal Arts and Sciences National University of Defense Technology Hunan Engineering Research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences College of Information and Communication National University of Defense Technology

Type-I generalized Feistel networks(GFN) are widely used frameworks in symmetric-key primitive designs such as CAST-256 and Lesamnta. Different from the extensive studies focusing on specific block cipher instances, the analysis against Type-I GFN structures gives generic security evaluation of the basic frameworks and concentrates more on the effect of linear transformation. Currently, works in this field mainly evaluate the security against impossible differential attack,zero-correlation linear attack, meet-in-the-middle attack and yoyo game attack, while its security evaluation against rectangle attack is still missing. In this paper, we filled this gap and gave the first structural analytical results of Type-I GFN against rectangle attack. By exploiting its structural properties, we proved there exists a boomerang switch for Type-I GFN for the first time,which is independent of the round functions. Then we turned the boomerang switch into chosen plaintext setting and proposed a new rectangle attack model. By appending 1 more round in the beginning of the boomerang switch, we constructed a rectangle distinguisher and a key recovery attack could be performed.

关键词： meet-in-the-middle attack basic frameworks boomerang switch rectangle attack model specific block cipher instances GFN structures cryptography generic security evaluation Feistel networks Data security key recovery attack linear transformation Cryptography theory rectangle distinguisher yoyo game attack symmetric-key primitive designs zero-correlation linear attack differential attack structural properties structural analytical results Cryptography Feistel structures

A Review on Recent Development of Cooling Technologies for Photovoltaic Modules

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Journal of Thermal Science 2020年第6期29卷 1410-1430页

作者： ZHANG Chunxiao shen chao WEI shen WANG Yuan LV Guoquan SUN Cheng Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologySchool of ArchitectureHarbin Institute of TechnologyHarbin 150090China The Bartlett School of Construction and Project Management University College London(UCL)London WC1E 7HBUK

When converting solar energy to electricity,a big proportion of energy is not converted for electricity but for heating PV cells,resulting in increased cell temperature and reduced electrical *** cooling technologies have been developed and used for PV modules to lower cell temperature and boost electric energy ***,little crucial review work was proposed to comment cooling technologies for PV ***,this paper has provided a thorough review of the up-to-date development of existing cooling technologies for PV modules,and given appropriate comments,comparisons and *** to the ways or principles of cooling,existing cooling technologies have been classified as fluid medium cooling(air cooling,water cooling and nanofluids cooling),optimizing structural configuration cooling and phase change materials *** influential factors and sub-methods were collected from the review work,and their contributions and impact have been discussed to guide future *** most cooling technologies reviewed in this paper are matured,there are still problems need to be solved,such as the choice of cooling fluid and its usability for specific regions,the fouling accumulation and cleaning of enhanced heat exchangers with complex structures,the balance between cooling cost and net efficiency of PV modules,the cooling of circulating water in tropical areas and the freezing of circulating water in cold *** be advocated,due to efficient heat transfer and spectral filter characters,nanofluids can promote the effective matching of solar energy at both spectral and spatial scales to achieve orderly energy utilization.

关键词： solar energy PV modules cooling technologies nanoparticles phase change materials

PS-HQ:More convenient in situ polymeric cocatalyst for the PdC1_2-catalyzed acetalization in supercritical carbon dioxide

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Chinese Chemical Letters 2007年第8期18卷 969-972页

作者： Zhao Yang Wang Huan feng Jiang chao Rong Qi Yan Xia shen Shao Rong Yang College of Chemistry South China University of Technology Guangzhou 510640 China Department of Chemistry South China Normal University Guangzhou 510006 China

Polystyrene-supported hydroquinone （PS-HQ） is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone （PS-BQ） in the PdCl2-catalyzed acetalization of methyl acrylate with methanol in supercritical carbon dioxide （scCO2） under oxygen atmosphere. Due to deletion of H2O2 oxidation step, PS-HQ is more convenient and relatively inexpensive.

关键词： Palladium chloride Polymeric supported catalyst Hydroquinone Oxidation Wacker reaction Molecular oxygen

Modified MUSIC estimation for correlated signals with compressive sampling arrays

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Journal of Systems Engineering and Electronics 2014年第5期25卷 755-760页

作者： Yan Jing Naizhang feng Yi shen School of Astronautics Harbin Institute of Technology School of Information and Electrical Engineering Harbin Institute of Technology in Weihai

This paper addresses the issue of the direction of arrival （DOA） estimation under the compressive sampling （CS） framework. A novel approach, modified multiple signal classification （MMUSIC） based on the CS array （CSA-MMUSIC）, is proposed to resolve the DOA estimation of correlated signals and two closely adjacent signals. By using two random CS matrices, a large size array is compressed into a small size array, which effectively reduces the number of the front end circuit. The theoretical analysis demonstrates that the proposed approach has the advantages of low computational complexity and hardware structure compared to other MMUSIC approaches. Simulation results show that CSAMMUSIC can possess similar angular resolution as MMUSIC.

关键词： direction of arrival (DOA) compressive sampling array (CSA) modified multiple signal classification (MMUSIC) correlated signal.

Quantitative interpretation to the chain mechanism of free radical reactions in cyclohexane pyrolysis

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Journal of Natural Gas Chemistry 2011年第5期20卷 507-514页

作者： Yingxian Zhao Bo shen feng Wei Ningbo Institute of Technology Zhejiang University Ningbo 315100 Zhejiang China

Pyrolysis of cyclohexane was conducted with a plug flow tube reactor in the temperature range of 873-973 K. Based on the experimental data, the mechanism and kinetic model of cyclohexane pyrolysis reaction were proposed. The kinetic analysis shows that overall conversion of cyclohexane is a first order reaction, of which the rate constant increased from 0.0086 to 0.0225 to 0.0623 s-1 with the increase of temperature from 873 to 923 to 973 K, and the apparent activation energy was determined to be 155.0±1.0 kJ mol-1. The mechanism suggests that the cyclohexane is consumed by four processes：the homolysis of C-C bond （Path I）, the homolysis of C-H bond （Path II） in reaction chain initia- tion, the H-abstraction of various radicals from the feed molecules in reaction chain propagation （Path III）, and the process associated with coke formation （Path IV）. The reaction path probability （RPP） ratio of XPath I：XPath II ： XPath III ： XPath IV was 0.5420：0.0045：0.3897：0.0638 at 873 K, and 0.4336 ： 0.0061 ： 0.4885 ： 0.0718 at 973 K, respectively.

关键词： cyclohexane pyrolysis free radicals chain mechanism kinetics selectivity

Construction of deterministic sensing matrix and its application to DOA estimation

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Journal of Systems Engineering and Electronics 2016年第1期27卷 10-19页

作者： Yi shen Yan Jing Naizhang feng School of Astronautics Harbin Institute of Technology School of Information and Electrical Engineering Harbin Institute of Technology at Weihai

Compressive sensing（CS） has emerged as a novel sampling framework which enables sparse signal acquisition and reconstruction with fewer measurements below the Nyquist *** important issue for CS is the construction of measurement matrix or sensing matrix.A new deterministic sensing matrix,named as OOC-B,is proposed by exploiting optical orthogonal codes（OOCs）,Bernoulli matrix and Singer structure,which has the entries of 0,＋1 and-1 before *** have proven that the designed deterministic matrix is asymptotically *** addition,the proposed deterministic sensing matrix is applied to direction of arrival（DOA） estimation of narrowband signals by CS arrays（CSA）processing and CS *** analysis and simulation results show that the proposed sensing matrix has good performance for DOA *** is very effective for simplifying hardware structure and decreasing computational complexity in DOA estimation by CSA ***,lower root mean square error（RMSE） and bias are obtained in DOA estimation by CS recovery.

关键词： deterministic sensing matrix optical orthogonal code(OOC) Bernoulli matrix compressive sensing(CS) direction of arrival(DOA).

Stability of second-order stochastic neutral partial functional differential equations driven by impulsive noises

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Science China(Information Sciences) 2016年第11期59卷 117-127页

作者： feng JIANG Hua YANG Yi shen School of Statistics and Mathematics Zhongnan University of Economics and Law School of Automation Huazhong University of Science and Technology School of Mathematics and Computer Science Wuhan Polytechnic University

This paper investigates the stability of second-order stochastic neutral partial functional differential equations driven by impulsive noises. Some sufficient conditions ensuring pth moment exponential stability of the second-order stochastic neutral partial functional differential equations driven by impulsive noises are obtained by establishing a new impulsive-integral inequality. These existing results are generalized and improved by the present study. Finally, an example is given to show the effectiveness of our results.

关键词： second-order stochastic neutral partial functional differential equations exponential stability impulsive noises sine family cosine family

Generative Adversarial Networks with Joint Distribution Moment Matching

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Journal of the Operations Research Society of China 2019年第4期7卷 579-597页

作者： Yi-Ying Zhang chao-Min shen Hao feng Preston Thomas Fletcher Gui-Xu Zhang Department of Computer Science East China Normal UniversityShanghai 200062China Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 200062China Westlake Institute for Brain-Like Science and Technology Hangzhou 310027China Didi Chuxing Science and Technology Co.Ltd. Beijing 100193China Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904USA

Generative adversarial networks(GANs)have shown impressive power in the field of machine *** GANs have focused on unsupervised learning *** recent years,conditional GANs that can generate data with labels have been proposed in semi-supervised learning and have achieved better image quality than traditional *** GANs,however,generally only minimize the difference between marginal distributions of real and generated data,neglecting the difference with respect to each class of the *** address this challenge,we propose the GAN with joint distribution moment matching(JDMM-GAN)for matching the joint distribution based on maximum mean discrepancy,which minimizes the differences of both the marginal and conditional *** learning procedure is iteratively conducted by the stochastic gradient descent and *** evaluate JDMM-GAN on several benchmark datasets,including MNIST,CIFAR-10 and the Extended Yale *** with the state-of-the-art GANs,JDMM-GAN generates more realistic images and achieves the best inception score for CIFAR-10 dataset.

关键词： Generative Adversarial Networks Joint Distribution Moment Matching Maximum mean discrepancy

Evaluation of commutation failure risk in single-or multi-infeed LCC-HVDC systems based on equivalent-fault method

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Science China(Technological Sciences) 2018年第8期61卷 1207-1216页

作者： ZHENG Kuan shen Chen LIU feng State Key Laboratory of Power Systems Department of Electrical Engineering Tsinghua University

In single-or multi-infeed line-commutated converter-based high-voltage direct current(LCC-HVDC) systems, commutation failure(CF) induced by alternating current(AC) faults may lead to serious consequences. Considering the randomness of fault occurrences, an accurate evaluation of the CF risk(CFR) from the system point of view becomes necessary in power system planning and operation. This paper first provides a definition of the CF severity(CFS) index corresponding to an AC fault. Then,on the basis of electromagnetic transient(EMT) simulation, an approach to calculate the CFS index considering the randomness of fault-occurrence time is presented. A novel equivalent-fault method is further put forward to make the EMT simulation scalable to calculate the CFS index in terms of a fault occurring in a large-scale receiving-end grid. Thereafter, the CFR index is introduced, which is defined as the sum of the products of the CFS index of each AC fault and the corresponding fault ***, the proposed method is verified on the modified IEEE 9-bus and modified IEEE 39-bus systems using PSCAD/EMTDC.

关键词： commutation failure severity equivalent-fault method commutation failure risk fault randomness electromagnetictransient simulations