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Zero-inflated non-central negative binomial distribution

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Applied Mathematics(A Journal of Chinese Universities) 2022年第2期37卷 187-198页

作者： TIAN Wei-zhong LIU Ting-ting YANG Yao-ting College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118China School of Science Xi'an University of TechnologyXi'an 710054China

In this article, the zero-inflated non-central negative binomial(ZINNB) distribution is introduced. Some of its basic properties are obtained. In addition, we use the maximum likelihood estimation method to estimate t... 详细信息

关键词： zero-in ated non-central negative binomial distribution maximum likelihood estimation good-ness of fit

The minimal measurement number for generalized conjugate phase retrieval

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Science China Mathematics 2022年第3期65卷 655-664页

作者： Wei Dan College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118China

The generalized conjugate phase retrieval problem aims to reconstruct a complex signal x ∈ C^(n) from quadratic measurements x*A_(1)x,...,x*A_(m)x,where A_(1),...,A_(m)∈R^(n×n) are real symmetric matrices.The equivalent formulation for generalized conjugate phase retrieval along with the minimal measurement number required for accurate retrieval(up to a global phase factor as well as conjugacy) is derived in this paper.We present a set of nine vectors in R^(4) and prove that it is conjugate phase retrievable on C^(4).This result implies the measurement number bound 4n-6 is not optimal for some n,which confirms a conjecture in the article by Evans and Lai(2019).

关键词： phase retrieval measurement number conjugate

Structured-Light-Field 3D Imaging System With Coaxial Projection

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激光与光电子学进展 2023年第8期60卷 261-267页

作者： Zhang Zhijun Wu Qingyang Jiang Yifan Deng Yifeng College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118GuangdongChina

This paper presents a novel 3D measurement method for a light field camera(LFC)in which 3D information of object space is encoded by a microlens array(MLA).The light ray corresponding to each pixel of the LFC is calibrated.Once the matching points from at least two subviews exhibit sub-pixel accuracy,the 3D coordinates can be calculated optimally by intersecting light rays of these points matched through phase coding.Moreover,the proposed method obtains high-resolved results that exceed the subview resolution due to the virtual continuous phase search strategy.Finally,we combine the LFC and coaxial projection to solve the 3D data loss caused by shadowing and occlusion problems.Experimental results verify the feasibility of the proposed method,and the measurement error is about 30μm in a depth range of 60 mm.

关键词： light field 3D imaging microlens array structured light

A Linear Homomorphic Proxy Signature Scheme Based on Blockchain for internet of Things

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1857-1878页

作者： Caifen Wang Bin Wu College of Big Data and Internet Shenzhen Technology UniversityShenzhen518118China School of Electronic and Information Engineering Lanzhou Jiaotong UniversityLanzhou730070China

The mushroom growth of IoT has been accompanied by the generation of massive amounts of data.Subject to the limited storage and computing capabilities ofmost IoT devices,a growing number of institutions and organizations outsource their data computing tasks to cloud servers to obtain efficient and accurate computation while avoiding the cost of local data computing.One of the most important challenges facing outsourcing computing is how to ensure the correctness of computation results.Linearly homomorphic proxy signature(LHPS)is a desirable solution to ensure the reliability of outsourcing computing in the case of authorized signing right.Blockchain has the characteristics of tamper-proof and traceability,and is a new technology to solve data security.However,as far as we know,constructions of LHPS have been few and far between.In addition,the existing LHPS scheme does not focus on homomorphic unforgeability and does not use blockchain technology.Herein,we improve the security model of the LHPS scheme,and the usual existential forgery and homomorphic existential forgery of two types of adversaries are considered.Under the new model,we present a blockchain-based LHPS scheme.The security analysis shows that under the adaptive chosen message attack,the unforgeability of the proposed scheme can be reduced to the CDH hard assumption,while achieving the usual and homomorphic existential unforgeability.Moreover,comparedwith the previous LHPS scheme,the performance analysis shows that our scheme has the same key size and comparable computational overhead,but has higher security.

关键词： Homomorphic signature proxy signature security model provable security unforgeability

Electricity Carbon Quota Trading Scheme based on Certificateless Signature and Blockchain

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1695-1712页

作者： Xiaodong Yang Runze Diao Tao Liu Haoqi Wen Caifen Wang college of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China Institute of China TelecomWanwei China TelecomWanwei Information Technology Co.Ltd.Lanzhou730030China College of Big Data and Internet Shenzhen Technology UniversityShenzhen518118China Key Laboratory of Cryptography and data Analytics Northwest Normal UniversityLanzhou730070China

The carbon tradingmarket can promote“carbon peaking”and“carbon neutrality”at low cost,but carbon emission quotas face attacks such as data forgery,tampering,counterfeiting,and replay in the electricity trading market.Certificateless signatures are a new cryptographic technology that can address traditional cryptography’s general essential certificate requirements and avoid the problem of crucial escrowbased on identity cryptography.However,most certificateless signatures still suffer fromvarious security flaws.We present a secure and efficient certificateless signing scheme by examining the security of existing certificateless signature schemes.To ensure the integrity and verifiability of electricity carbon quota trading,we propose an electricity carbon quota trading scheme based on a certificateless signature and blockchain.Our scheme utilizes certificateless signatures to ensure the validity and nonrepudiation of transactions and adopts blockchain technology to achieve immutability and traceability in electricity carbon quota transactions.In addition,validating electricity carbon quota transactions does not require time-consuming bilinear pairing operations.The results of the analysis indicate that our scheme meets existential unforgeability under adaptive selective message attacks,offers conditional identity privacy protection,resists replay attacks,and demonstrates high computing and communication performance.

关键词： Electricity carbon trading certificateless signature blockchain forgery attack carbon quota

Transductive Transfer Dictionary Learning Algorithm for Remote Sensing Image Classification

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2267-2283页

作者： Jiaqun Zhu Hongda Chen Yiqing Fan Tongguang Ni Aliyun School of big data Changzhou UniversityChangzhou213164China Hua Lookeng Honors college Changzhou UniversityChangzhou213164China

To create a green and healthy living environment,people have put forward higher requirements for the refined management of ecological resources.A variety of technologies,including satellite remote sensing,internet of Things,artificial intelligence,and big data,can build a smart environmental monitoring system.Remote sensing image classification is an important research content in ecological environmental monitoring.Remote sensing images contain rich spatial information andmulti-temporal information,but also bring challenges such as difficulty in obtaining classification labels and low classification accuracy.To solve this problem,this study develops a transductive transfer dictionary learning(TTDL)algorithm.In the TTDL,the source and target domains are transformed fromthe original sample space to a common subspace.TTDL trains a shared discriminative dictionary in this subspace,establishes associations between domains,and also obtains sparse representations of source and target domain data.To obtain an effective shared discriminative dictionary,triple-induced ordinal locality preserving term,Fisher discriminant term,and graph Laplacian regularization termare introduced into the TTDL.The triplet-induced ordinal locality preserving term on sub-space projection preserves the local structure of data in low-dimensional subspaces.The Fisher discriminant term on dictionary improves differences among different sub-dictionaries through intra-class and inter-class scatters.The graph Laplacian regularization term on sparse representation maintains the manifold structure using a semi-supervised weight graphmatrix,which can indirectly improve the discriminative performance of the dictionary.The TTDL is tested on several remote sensing image datasets and has strong discrimination classification performance.

关键词： Classification dictionary learning remote sensing image transductive transfer learning

Federated learning privacy incentives:Reverse auctions and negotiations

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1538-1557页

作者： Hongqin Lyu Yongxiong Zhang Chao Wang Shigong Long Shengnan Guo Guizhou Provincial Key Laboratory of Public big data Guizhou UniversityGuiyangChina college of Computer Science and Technology Guizhou UniversityGuiyangChina

The incentive mechanism of federated learning has been a hot topic,but little research has been done on the compensation of privacy loss.To this end,this study uses the Local SGD federal learning framework and gives a theoretical analysis under the use of differential privacy protection.Based on the analysis,a multi‐attribute reverse auction model is proposed to be used for user selection as well as payment calculation for participation in federal learning.The model uses a mixture of economic and non‐economic attributes in making choices for users and is transformed into an optimisation equation to solve the user choice problem.In addition,a post‐auction negotiation model that uses the Rubinstein bargaining model as well as optimisation equations to describe the negotiation process and theoretically demonstrate the improvement of social welfare is proposed.In the experimental part,the authors find that their algorithm improves both the model accuracy and the F1‐score values relative to the comparison algorithms to varying degrees.

关键词： artificial intelligence data privacy decision making internet of things

The Birth–death Processes with Regular Boundary: Stationarity and Quasi-stationarity

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Acta Mathematica Sinica,English Series 2022年第5期38卷 890-906页

作者： Wu Jun GAO Yong Hua MAO Chi ZHANG College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118P.R.China School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex SystemsMinistry of EducationBeijing 100875P.R.China college of Mathematical Sciences Ocean University of ChinaQingdao 266100P.R.China

For the birth–death Q-matrix with regular boundary,its minimal process and its maximal process are closely related.In this paper,we obtain the uniform decay rate and the quasi-stationary distribution for the minimal process.And via the construction theory,we mainly derive the eigentime identity and the distribution of the fastest strong stationary time(FSST)for the maximal process.

关键词： Birth-death process regular boundary eigenvalue hitting time strong stationary time quasi-stationary distribution

Mobility in China, 2020: a tale of four phases

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National Science Review 2021年第11期8卷 110-120页

作者： Suoyi Tan Shengjie Lai Fan Fang Ziqiang Cao Bin Sai Bing Song Bitao Dai Shuhui Guo Chuchu Liu Mengsi Cai Tong Wang Mengning Wang Jiaxu Li Saran Chen Shuo Qin Jessica R.Floyd Zhidong Cao Jing Tan Xin Sun Tao Zhou Wei Zhang Andrew J.Tatem Petter Holme Xiaohong Chen Xin Lu School of Business Central South University Institute of big data and internet Innovations Hunan University of Technology and Business college of Systems Engineering National University of Defense Technology WorldPop School of Geography and Environmental ScienceUniversity of Southampton School of Mathematics and big data Foshan University State Key Laboratory on Blind Signal Processing State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences Chinese Evidence-Based Medicine Center National Clinical Research Center for Geriatrics West China Hospital Sichuan University big data Research Center University of Electronic Science and Technology of China West China Biomedical big data Center West China Hospital Sichuan University Tokyo Tech World Hub Research Initiative Institute of Innovative Research Tokyo Institute of Technology

2020 was an unprecedented year,with rapid and drastic changes in human mobility due to the COVID-19 pandemic.To understand the variation in commuting patterns among the Chinese population across stable and unstable periods,we used nationwide mobility data from 318 million mobile phone users in China to examine the extreme fluctuations of population movements in 2020,ranging from the Lunar New Year travel season(chunyun), to the exceptional calm of COVID-19 lockdown,and then to the recovery period.We observed that cross-city movements,which increased substantially in chunyun and then dropped sharply during the lockdown,are primarily dependent on travel distance and the socio-economic development of cities.Following the Lunar New Year holiday,national mobility remained low until mid-February,and COVID-19 interventions delayed more than 72.89 million people returning to large cities.Mobility network analysis revealed clusters of highly connected cities,conforming to the social-economic division of urban agglomerations in China.While the mass migration back to large cities was delayed,smaller cities connected more densely to form new clusters.During the recovery period after travel restrictions were lifted,the netflows of over 55% city pairs reversed in direction compared to before the lockdown.These findings offer the most comprehensive picture of Chinese mobility at fine resolution across various scenarios in China and are of critical importance for decision making regarding future public-health-emergency response,transportation planning and regional economic development,among others.

关键词： human mobility travel restrictions COVID-19 mobile phone data behavioral response