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The rapid expansion of the Internet of Things (IoT) and advancements in quantum computing pose security challenges for IoT systems, encompassing classical attacks and quantum attacks. In this work, we concentrate on secure information exchange in the quantum IoT, mainly addressing the problem of establishing direct and secure quantum dialogue between two authorized IoT nodes located at a distance. The nonlocal quantum orthogonal product basis (OPB) is adopted for the first time, to our best knowledge, in a controlled quantum dialogue protocol, which eliminates the need for pre-key sharing or key storage. Through uniquely corresponding operations, private information is encrypted onto the nonlocal OPB, which is transmitted in one way. Compared with entangled states, the OPB is easier to prepare, thus reducing the quantum capability required for IoT nodes. Our approach achieves high transmission efficiency (57.1%) and qubit efficiency (100%) while providing comprehensive security measures that withstand various attacks and effectively prevent information leakage. Furthermore, an OPB-based self-error-correction quantum repeater is proposed to mitigate noise in the communication channel between distant IoT nodes. This repeater requires fewer physical resources compared with repeaters based on entangled states.

Porous carbon has been intensively used for microwave absorption in merits of its outstanding specific surface area and dielectric properties. This study investigates the microwave absorption capacity of saturated wood-based activated carbon (SWAC) which was used for methylene blue treatment. The results demonstrate that SWAC, subjected to high temperature calcination, exhibits excellent microwave absorption properties. The structure, composition, micro-morphology, and electromagnetic parameters of SWAC were comprehensively analyzed using various techniques. The findings reveal that after calcination, SWAC possesses a rich pore structure, optimized material impedance matching, and the introduction of N atoms from the organic substance methylene blue into the carbon lattice of SWAC, thereby providing dipole polarization loss. These properties significantly contribute to its microwave absorption performance. The optimal reflection loss of SWAC at 6 GHz reaches −50.29 dB with an effective absorption bandwidth of 2.01 GHz, achieved at a calcination temperature of 700 °C and a paraffin matrix additive amount of 25%. The one-step treatment of SWAC proves to be a competitive and cost-effective method for producing microwave absorbers, which holds significant importance for the recovery of SWAC.

Most of the voice spoofing detection methods are designed for specific kinds of spoofing attacks, synthetic or replay. In practice, however, there is no prior information about these two kinds of spoofing attacks. To this end, this paper proposes a generalized voice spoofing detection method based on integral knowledge amalgamation to detect jointly synthetic attacks and replay attacks. Two amalgamation mechanisms, feature amalgamation and structure amalgamation, are designed from different perspectives, so that the model can generalize better and run fast. Specifically, the feature amalgamation transfers the high-level sematic knowledge from two teacher models to the compact model. The structure amalgamation employs the adversarial learning to ensure the global structure consistency of two teacher models and a student model. In addition, the feature matching loss is introduced to capture the distinctive features of synthetic attacks and replay attacks. We conduct extensive experiments on logical access (LA) scenario and physical access (PA) scenario of ASVspoof 2019 dataset to verify the validity of the proposed method. The experimental results show that compared with the most advanced generalized voice spoofing detection methods, the proposed method achieves a comparable or even better performance. In particular, our method gains the state-of-the-art detection capability on LA scenario. Moreover, our method achieves similar or even outstanding detectability when compared with specialized anti-spoofing methods.

A novel fluorescent probe, LCH, based on dicyanisophorone and carbazole, was prepared for the visual detection of Cu2+. The probe LCHcould recognize Cu2+by fluorescence quenching in EtOH/H2O (1/4, v/v) solution, which could be easily identified under the 365 nm UV lamp, and the detection limit was as low as 0.785 μM. The recognition mechanism of probe LCHwith Cu2+was determined by combining 1H NMR titration, MS, and theoretical calculations. Practical application experiments showed that probe LCHcould be used to detect Cu2+in the test strip experiments. Cell imaging experiments showed that the probe LCHowned good cell permeability and could be applied to the imaging of Cu2+in HepG2 cells. In addition, fluorescence colocalization experiments showed that LCHcould target lipid droplets. These results indicate that the probe LCHwill have a good application prospect in environmental detection and clinical medicine. A novel fluorescent probe LCH based on dicyandiamide, isophorone, and carbazole is proposed for the visual detection of Cu2+by fluorescence quenching. Its recognition mechanism is that Cu2+first coordinates with nitrogen atom and oxygen atom of the probe LCH and then hydrolyzes to form compound 2, which leads to “off” fluorescence. In addition, the fluorescent probe not only exhibited good cell permeability but also could target lipid droplets, and fluorescence imaging was successfully used to detect exogenous Cu2+in cells.

Data interaction scenarios involving multiple parties in network communities have problems of trust, data security, and reliability of the parties, and secure multiparty computation(SMPC) can effectively solve these problems. To address the security and fairness issues of SMPC, this study considers that semi-honest participants can lead to deviations in the security and fairness of the protocol, and combines information entropy and mutual information to present an n-round information exchange protocol in which each participant broadcasts a relevant information value in each round without revealing other information. The uncertainty of the correct outcome value is blurred by the interaction information in each round, and each participant is not sure of the correct outcome value until the end of the protocol, which effectively prevents malicious behavior and ensures the correct execution of the protocol. Security and fairness analysis shows that our protocol guarantees the security and relative fairness of the output obtained by the participants after completing the protocol.

As a significant part of the Internet of things, wireless sensor networks (WSNs) is frequently implemented in our daily life. Data aggregation in WSNs can realize limited transmission and save energy. In the process of data aggregation, node data information is vulnerable to be eavesdropped and attacked. Therefore, it is of great significance to the research of data aggregation privacy protection in WSNs. We propose a secure and efficient privacy-preserving data aggregation algorithm (SECPDA) based on the original clustering privacy data aggregation algorithm. In this algorithm, we utilize SEP protocol to dynamically select cluster head nodes, introduce slicing idea for the private data slicing, and generate false information for interference. A comprehensive experimental evaluation is conducted to assess the data traffic and privacy protection performance. The results demonstrate that the proposed SECPDA algorithm can effectively reduce data traffic and further improve data privacy of nodes.

Security and privacy are desired core issues to secure communication for the roaming service in global mobility network (GLOMONET). Authentication mechanism is an essential technology to establish a shared secret key between two or more participants who wish to encrypt sensitive data. How to design an ideal authenticated key agreement (AKA) that satisfies different security requirements is a very challenging task due to a handshake between participants is performed over an open channel. Multiple papers on AKA are currently available. We review a recently GLOMONET-oriented AKA released by Gope–Hwang. We point out that their scheme has various security problems. Specifically, their AKA is vulnerable to known session-specific temporary information attack. More seriously, the password renewal phase of their scheme is wrong, thus leading to the mobile user login failed and even the server rejects service. So the paper attempts to eliminate three security loopholes troubled in Gope–Hwang's scheme. Our objective is to propose an elliptic curve cryptography (ECC) based AKA to achieve secure implementation in GLOMONET. By performing informal and formal analyses, we demonstrate that our scheme overcomes some disadvantages in Gope–Hwang's scheme while possessing more excellent security attributes.

Verifiable computation (VC) paradigm has got the captivation that in real term is highlighted by the concept of third party computation. In more explicate terms, VC allows resource constrained clients/organizations to securely outsource expensive computations to untrusted service providers, while acquiring the publicly or privately verifiable results. Many mainstream solutions have been proposed to address the diverse problems within the VC domain. Some of them imposed assumptions over performed computations, while the others took advantage of interactivity /non-interactivity, zero knowledge proofs, and arguments. Further proposals utilized the powers of probabilistic checkable or computationally sound proofs. In this survey, we present a chronological study and classify the VC proposals based on their adopted domains. First, we provide a broader overview of the theoretical advancements while critically analyzing them. Subsequently, we present a comprehensive view of their utilization in the state of the art VC approaches. Moreover, a brief overview of recent proof based VC systems is also presented that lifted up the VC domain to the verge of practicality. We use the presented study and reviewed results to identify the similarities and alterations, modifications, and hybridization of different approaches, while comparing their advantages and reporting their overheads. Finally, we discuss implementation of such VC based systems, their applications, and the likely future directions.

This paper proposes a High quality data hiding in halftone image based on block conjugate (HQDHBC). We construct Least mean square filters (LMSF), and using LMSFs to evaluate the quality of halftone images. This paper proposes block conjugate property, and this property can be applied to hide a secret pattern. Therefore a data hiding method based on block conjugate can be proposed, and in this method two images should be divided into multiple blocks of M x N pixels, and in the corresponding block if the first M x N -1 pixels are conjugate or identical, the last pixel can implement normal halftone method instead of date hiding methods. Experimental results show that the proposed HQDHBC can be applied in gray-scale and color error diffused halftone images, and through implementing this method, not only the quality of halftone images can be improved, but also the Correct decoding rate (CDR) of revealed pattern can be guaranteed.

As a special factorization category of finite groups, logarithmic signature (LS) is used as the main component of cryptographic keys that operate within secret key cryptosystems such as PGM and public key cryptosystems like MST1, MST2and MST3. An LS with the shortest length is called a minimal logarithmic signature (MLS) that constitutes of the smallest sized blocks and offers the lowest complexity, and is therefore desirable for cryptographic constructions. However, the existence of MLSs for finite groups should be firstly taken into an account. The MLS conjecture states that every finite simple group has an MLS. If it holds, then by the consequence of Jordan-Hölder Theorem, every finite group would have an MLS. In fact, many cryptographers and mathematicians are keen for solving this problem. Some effective work has already been done in search of MLSs for finite groups. Recently, we have made some progress towards searching a minimal length key for MST cryptosystems and presented a theoretical proof of MLS conjecture. 根据有限单群的分类定理,本文利用有限群论、代数群论、射影几何等学科的相关理论给出了剩余四种单群极小对数签名的结构,最终从理论上完成MLS 猜想的证明,为MST 密码系统提供了广阔的应用平台。具体成果如下: (a) 给出了一类经典单群极小对数签名的构造。(b) 给出了一类经典单群—射影特殊酉群极小对数签名的构造。 (c) 构造了所有十类特殊李型群的极小对数签名。 (d) 构造了剩余十三类零散群的极小对数签名。

Cyber security lacks comprehensive theoretical guidance. General security theory, as a set of basic security theory concepts, is intended to guide cyber security and all the other security work. The general theory of security aims to unify the main branches of cyber security and establish a unified basic theory. This paper proposal an overview on the general theory of security, which is devoted to constructing a comprehensive model of network security. The hierarchical structure of the meridian-collateral tree is described. Shannon information theory is employed to build a cyberspace security model. Some central concepts of security, i.e., the attack and defense, are discussed and several general theorems on security are presented.

A novel robust audio watermarking algorithm based on empirical mode decomposition is proposed. The intrinsic feature of the final residual decomposed from the audio frame is selected to embed watermark and the algorithm works by shifting each element of the final residual to make its sum greater or less than 0. The experimental results show that the proposed algorithm does not change the property of the final residual after embedding watermark and the watermark is robust against various kinds of attacks. Compared with existing classic algorithms based on Empirical mode decomposition (EMD), the proposed algorithm largely improves both the robustness and imperceptibility of watermarking.

Blockchain is a technology that uses community validation to synchronize the content of ledgers replicated by multiple users. Although Blockchain derives its origins from technologies introduced decades ago, recently it has received an astonishing amount of attention in both academic and industry due to its characteristics of decentralization, point-to-point transmission, transparency, traceability, non-tampering, and data security. Both researchers and practitioners have recognized that Blockchain can be used to solve complex technical or socio-economic problems. In recent times, a number of blockchain-based applications have been released in the literature and Blockchain's approaches are used to other cases. For example, as an emerging distributed architecture and computing paradigm, Blockchain technologies have accelerated the development/application of the Internet of Things, Artificial Intelligence, Cloud/Edge Computing, Social Networking, Finance, Insurance, Healthcare, and Supply Chain Management. The popularity and rapid development of Blockchain bring many technical and regulatory challenges for research communities. There is a pressing need to balance between technical and regulatory requirements.

We mainly consider quantum multi-unicast problem over directed acyclic network, where each source wishes to transmit an independent message to its target via bottleneck channel. Taking the advantage of global entanglement state 2D and 3D cluster states, these problems can be solved efficiently. At first, a universal scheme for the generation of resource states among distant communication nodes is provided. The corresponding between cluster and bigraph leads to a constant temporal resource cost. Furthermore, a new approach based on stabilizer formalism to analyze the solvability of several underlying quantum multi-unicast networks is presented. It is found that the solvability closely depends on the choice of stabilizer generators for a given cluster state. And then, with the designed measurement basis and parallel measurement on intermediate nodes, we propose optimal protocols for these multi-unicast sessions. Also, the analysis reveals that the resource consumption involving spatial resources, operational resources and temporal resources mostly reach the lower bounds.

Ciphertext-policy attribute-based encryption (CP-ABE) is becoming a promising solution to guarantee data security in cloud computing. In this paper, we present an attribute-based secure data sharing scheme with Efficient revocation (EABDS) in cloud computing. Our scheme first encrypts data with Data encryption key (DEK) using symmetric encryption and then encrypts DEK based on CP-ABE, which guarantees the data confidentiality and achieves fine-grained access control. In order to solve the key escrow problem in current attribute based data sharing schemes, our scheme adopts additively homomorphic encryption to generate attribute secret keys of users by attribute authority in cooperation with key server, which prevents attribute authority from accessing the data by generating attribute secret keys alone. Our scheme presents an immediate attribute revocation method that achieves both forward and backward security. The computation overhead of user is also reduced by delegating most of the decryption operations to the key server. The security and performance analysis results show that our scheme is more secure and efficient.

Concolic testing is an integrated approachof symbolic execution and dynamic analysis, which iswidely adopted by security researchers for program behavioranalysis. This approach fails on hidden path discoveryof environment-intensive program. We investigated onexisting concolic testing tools and found out that severalof them does not take this issue into account while otherssolved this issue with overloaded working model. Weproposed a systematic and unified approach of automaticallyidentifying and modifying the output of the Datainput interacting functions (DIIF) based on fine-grainedtaint analysis, which detects and updates the data interactingwith the runtime environment and generating a newcustomized set of inputs to execute hidden paths, to revealthe hidden paths on only particular runtime configurationor context. A prototype was developed and evaluated witha set of complex and environment-intensive programs. Theexperimental result demonstrated that our approach coulddetect the DIIF precisely and improve the code coverage.

A novel compressive sensing-based audio semi-fragile zero-watermarking algorithm is proposed in this paper. This algorithm transforms the original audio signal into the wavelet domain and applies compressive sensing theory to the approximation wavelet coefficients. The zero-watermarking is constructed according to the positive and negative properties of elements in the measurement vector. The experimental results show that the proposed algorithm is robust against common audio signal processing and fragile to malicious tampering. Compared with the existing algorithms, the proposed algorithm improves malicious tampering detection accuracy in common audio signal processing environments.

A universal entangler is a very powerful fault-tolerant entangling device for generating quantum entanglements from any joint states. Our paper aims to address the construction of universal entanglers. We prove that universal entanglers may be obtained from random unitary gates according to the Harr measure. The success probability is close to 1 for large system spaces. This result represents the typical density of entanglement subspaces in large state spaces. It also partially solves an open problem of universal bipartite entanglers and is explained by some experiment simulations.

In this paper, we regard the nonlinear feedback shift register (NLFSR) as a special Boolean network, and use semi-tensor product of matrices and matrix expression of logic to convert the dynamic equations of NLFSR into an equivalent algebraic equation. Based on them, we propose some novel and generalized techniques to study NLFSR. First, a general method is presented to solve an open problem of how to obtain the properties (the number of fixed points and the cycles with different lengths) of the state sequences produced by a given NLFSR, i.e., the analysis of a given NLFSR. We then show how to construct all $$2^{2^n - (l - n)} /2^{2^n - l}$$shortest n-stage feedback shift registers (nFSR) and at least $$2^{2^n - (l - n) - 1} /2^{2^n - l - 1}$$shortest n-stage nonlinear feedback shift registers (nNLFSR) which can output a given nonperiodic/periodic sequence with length l. Besides, we propose two novel cycles joining algorithms for the construction of full-length nNLFSR. Finally, two algorithms are presented to construct $$2^{2^{n - 2} - 1}$$different full-length nNLFSRs, respectively.

In order to achieve fine-grained access control in cloud computing, existing digital rights management (DRM) schemes adopt attribute-based encryption as the main encryption primitive. However, these schemes suffer from inefficiency and cannot support dynamic updating of usage rights stored in the cloud. In this paper, we propose a novel DRM scheme with secure key management and dynamic usage control in cloud computing. We present a secure key management mechanism based on attribute-based encryption and proxy re-encryption. Only the users whose attributes satisfy the access policy of the encrypted content and who have effective usage rights can be able to recover the content encryption key and further decrypt the content. The attribute based mechanism allows the content provider to selectively provide fine-grained access control of contents among a set of users, and also enables the license server to implement immediate attribute and user revocation. Moreover, our scheme supports privacy-preserving dynamic usage control based on additive homomorphic encryption, which allows the license server in the cloud to update the users' usage rights dynamically without disclosing the plaintext. Extensive analytical results indicate that our proposed scheme is secure and efficient.

A hierarchical identity-based broadcast encryption (H-IBBE) scheme is an identity-based broadcast encryption (IBBE) scheme in a hierarchical environment. In order to obtain secure H-IBBE schemes in the quantum era, we propose an H-IBBE scheme based on the learning with errors problem assumption. Our scheme achieves indistinguishability from random under adaptive chosen-plaintext and chosen-identity attacks in the random oracle model.

Recently, some blind quantum signature (BQS) protocols have been proposed. But the previous schemes have security and efficiency problems. Based on the entangled Greenberger-Horne-Zeilinger (GHZ) states, a new weak BQS protocol is proposed. Compared with some existing schemes, our protocol has 100% efficiency. Besides, the protocol is simple and easy to implement. The security of the protocol is guaranteed by the correlation of the GHZ particles held by each participant. In our protocol, the signatory is kept blind from the content of the message. According to the security analysis, the signatory cannot disavowal his/her signature while the signature cannot be forged by others.

In this paper, we first propose a hidden rule among the secure message, the initial tensor product of two Bell states and the final tensor product when respectively applying local unitary transformations to the first particle of the two initial Bell states, and then present a high-efficiency quantum steganography protocol under the control of the hidden rule. In the proposed quantum steganography scheme, a hidden channel is established to transfer a secret message within any quantum secure direct communication (QSDC) scheme that is based on 2-level quantum states and unitary transformations. The secret message hiding/unhiding process is linked with the QSDC process only by unitary transformations. To accurately describe the capacity of a steganography scheme, a quantitative measure, named embedding efficiency, is introduced in this paper. The performance analysis shows that the proposed steganography scheme achieves a high efficiency as well as a good imperceptibility. Moreover, it is shown that this scheme can resist all serious attacks including the intercept-resend attack, measurement-resend attack, auxiliary particle attack and even the Denial of Service attack. To improve the efficiency of the proposed scheme, the hidden rule is extended based on the tensor product of multiple Bell states.

Abstract: In recent years, with the development of quantum cryptography, quantum signature has also made great achievement. However, the effectiveness of all the quantum signature schemes reported in the literature can only be verified by a designated person. Therefore, its wide applications are limited. For solving this problem, a new quantum proxy signature scheme using EPR quantum entanglement state and unitary transformation to generate proxy signature is presented. Proxy signer announces his public key when he generates the final signature. According to the property of unitary transformation and quantum one-way function, everyone can verify whether the signature is effective or not by the public key. So the quantum proxy signature scheme in our paper can be public verified. The quantum key distribution and one-time pad encryption algorithm guarantee the unconditional security of this scheme. Analysis results show that this new scheme satisfies strong non-counterfeit and strong non-disavowal.

Abstract: The development of quantum computation casts serious threats to the securities of most existing public-key cryptosystems. Braid-based cryptography is one of the alternatives that have potential advantages in resisting quantum attacks. In this paper, the state of the art of braid cryptography is surveyed, and then a new cryptographic problem—conjugate adjoining problem related to braid groups is proposed. Based on this problem, we design a new braid-based signature scheme. This scheme is efficient and provably secure in the random oracle model. Further, we present the comparison between braid-based signatures and RSA-based ones. The signing process of the braid-based schemes is more efficient than that of RSA-based ones, while the verifying process of the braid-based ones is observably slow. Hence, braid-based signatures are suitable for scenarios where the signing process has to be as quick as possible but delays are permitted in the verifying process, for example, in off-line e-cash systems. The key sizes in braid-based schemes are considerably large—about 2K bits in the case of secret keys and 12K bits in the case of public keys. However, braid operations are much simpler and more efficient than modular exponential operations. Therefore, braid-based schemes can be embedded into devices with low computational ability and large memory space. The capability of braid cryptosystems to resist currently known quantum attacks is also discussed from the perspective of hidden subgroup problems.

Abstract: Our concern, in the paper, is to construct information-theoretic secure network coding in the presence of eavesdroppers. Based on the generalized attack model and all-or-nothing transformation, the security of network coding in the generalized combination network can be characterized by the network capacity and the min-cut bound of wiretapping set from the source. Furthermore, it can be extended to any directed acyclic networks with single source. Compared with the traditional results, we construct information-theoretic secure network coding without additional encryptions and giving up any capacity.

Abstract: In this paper, we introduce a chaotic optimization method, called CAS (chaotic ant swarm), to solve the problem of designing a fuzzy system to identify dynamical systems. The position vector of each ant in the CAS algorithm corresponds to the parameter vector of the selected fuzzy system. At each learning time step, the CAS algorithm is iterated to give the optimal parameters of fuzzy systems based on the fitness theory. Then the corresponding CAS-designed fuzzy system is built and applied to the identification of the unknown nonlinear dynamical systems. Numerical simulation results are provided to show the effectiveness and feasibility of the developed CAS-designed fuzzy system. [Copyright &y& Elsevier]

Abstract: This paper proposes a technique aiming to compute all global minimizers, while avoiding local minimizers, through chaotic ant swarm (CAS) optimization method. This technique incorporates the recently proposed deflection and repulsion techniques to alleviate local minimizers. Those approaches can be used in combination with CAS to detect all global minimizers effectively. The performance of the algorithm is illustrated on test problems of global optimization. Experimental results indicate the effectiveness of the proposed algorithm. [Copyright &y& Elsevier]

Abstract: Through the construction of a suitable fitness function, the problem of parameters estimation of the chaotic system is converted to that of parameters optimization. In this paper, an optimization method, called CAS (chaotic ant swarm), is developed to solve the problem of searching for the optimal. Finally numerical simulations are provided to show the effectiveness and feasibility of the developed method. [Copyright &y& Elsevier]

Abstract: Based on the stability theory of time-delay systems, the synchronization problem of chaotic systems with time-varying lags is discussed. Through the analysis of the error dynamical systems, the time-delay correlative synchronization controller is designed to achieve chaos synchronization. Finally, numerical simulations are provided to verify the effectiveness and feasibility of the developed method. [Copyright &y& Elsevier]

In this paper, we study the propagation characteristics of rumors in an institution and develop the rumor dissemination model inside the institution. Different from the traditional model, a person in the proposed model can make a judgement about the message and decide to propagate it or refute it, and most people inside the institution can refute the rumor spreaders and propagate the genuine messages to uninformed people when they have confirmed the message is a rumor. Then, we split all the people into two institutions (inside and outside). Since the rumors and genuine messages from the institution can have a non-negligible impact on people outside the institution, we put forward a new double-institution rumor propagation model, and the model considers the impact of messages on the inside and outside of the institution simultaneously. Based on the two proposed models, the basic reproduction numbers are obtained respectively, and the local and global stability of the rumor-free equilibrium points are discussed separately. We numerically simulate the propagation of rumors in small-world networks. The simulation is carried out to verify the validity of the proposed model, and our model is closer to the reality than traditional models. [ABSTRACT FROM AUTHOR]

Highlights • We discuss the decay synchronization problem of CMTDNs. • We design a novel nonlinear feedback controller and a Lyapunov function. • Some sufficient conditions are derived to ensure the decay synchronization of CMTDNs/CMDNs. • The main results can easily extended to exponential synchronization, polynomial synchronization and logarithmic synchronization. • Two simulations are shown to present the correctness of the main results. Abstract In this paper, we discuss the decay synchronization of complex multi-links time-varying dynamic networks (CMTDNs) for the first time. The exponential synchronization, polynomial synchronization and logarithmic synchronization can be seen as the special cases of the decay synchronization. CMTDNs are more general and realistic than the complex network with the single-link. By virtue of the definitions of the ψ -type function and ψ -type stability, we give the definition of the decay synchronization of the drive-response CMTDNs. Some novel and easily validated sufficient conditions are deduced to ensure the decay synchronization of drive-response CMTDNs based on the Lyapunov stability theory with the help of a novel nonlinear feedback controller and a new Lyapunov–Krasovskii function. Finally, two numerical simulations have been given to verify the correctness of main results. [ABSTRACT FROM AUTHOR]

Highlights • We investigate finite-time modified projective synchronization problems of memristor-based neural networks with multi-links (MNNLs) and leakage & discrete time-varying delays, which can be extended to studies of common MNNs or common complex networks. • Two different kinds of finite-time synchronization methods are adopted to ensure the finite-time modified projective synchronization. And the adaptive feedback controller can be degraded to the general controller. • The main results can be easily extended to the studies of complete synchronization, projective synchronization and anti-synchronization. Abstract This paper investigates the finite-time modified projective synchronization problem of memristor-based neural networks with multi-links (MNNLs). And leakage and discrete time-varying delays (mixed delays) are considered in the MNNLs model. By designing a delay-dependent controller and an adaptive controller, the drive-response systems can reach finite-time modified projective synchronization with arbitrary constants. Based on two kinds of finite-time stability theories and some differential inequalities, several finite-time modified projective synchronization criteria are obtained with the Lyapunov stability method. Besides, several corollaries about the special cases of finite-time modified projective synchronization are given along with the proposed theorems. At last, three numerical simulations are given to illustrate the effectiveness and verify the correctness of our results. [ABSTRACT FROM AUTHOR]

Abstract This paper mainly investigates the fixed-time synchronization of memristor-based fuzzy cellular neural network (MFCNN) with time-varying delay. By utilizing differential inclusion, set-valued map theory, the definitions of finite-time and fixed-time stability, we convert the fixed-time synchronization control of the drive-response MFCNN into the equivalent fixed-time stability problem of the error system between the drive-response systems. Some novel sufficient conditions are derived to guarantee the fixed-time synchronization of the drive-response MFCNN based on a simple Lyapunov function and a nonlinear feedback controller. Meanwhile, the settling time can be estimated by simple calculations. Furthermore, these fixed-time synchronization criteria here are easy to validate and extend to the MFCNN without time-varying delay and general memristor-based neural networks. Finally, three numerical examples are given to illustrate the correctness of the main results. [ABSTRACT FROM AUTHOR]

This paper mainly studies the finite-time stability and synchronization problems of memristor-based fractional-order fuzzy cellular neural network (MFFCNN). Firstly, we discuss the existence and uniqueness of the Filippov solution of the MFFCNN according to the Banach fixed point theorem and give a sufficient condition for the existence and uniqueness of the solution. Secondly, a sufficient condition to ensure the finite-time stability of the MFFCNN is obtained based on the definition of finite-time stability of the MFFCNN and Gronwall–Bellman inequality. Thirdly, by designing a simple linear feedback controller, the finite-time synchronization criterion for drive-response MFFCNN systems is derived according to the definition of finite-time synchronization. These sufficient conditions are easy to verify. Finally, two examples are given to show the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

In this paper, we study the fixed-time synchronization of hybrid coupled networks, which have only one transmittal delay in the delayed coupling terms. The settling time of fixed-time synchronization can be adjusted to some desired values in advance regardless of the initial conditions. By constructing suitable Lyapunov functions and designing delay-dependent feedback controllers, we derive several novel synchronization criteria, which guarantee the considered hybrid coupled networks can achieve fixed-time synchronization. Two numerical examples are given to show the effectiveness of our results. [ABSTRACT FROM AUTHOR]

In this paper, we mainly investigate the finite-time generalized projective lag synchronization of neutral-type neural network with delay. With the help of the definition of finite-time generalized projective lag synchronization and Gronwall–Bellman inequality, the generalized projective lag synchronization is achieved between drive-response neural networks via a nonlinear feedback controller. Some novel and easily verifiable sufficient conditions are obtained. Many existing works can be regarded as special cases of our conclusions. Finally, we provide two simulation examples to verify the correctness of main results. [ABSTRACT FROM AUTHOR]

In this paper, a class of periodically switch control method is proposed to achieve finite-time parameters tracking identification and synchronization for multi-link complex networks. This periodically switch control is an optimal control, two convertible control intensities are given in a fixed period instead of continuous high control intensity. Meanwhile, we give an effective analysis for complex network model with multiple constant time-delays and time-varying delays, we overcome these difficulties of time-delays and unknown parameters. The parameters estimation, topological identification are achieved based on parameters tracking identification of drive-response networks. Meanwhile, the corresponding identification and synchronization criteria are obtained based on Lyapunov function, linear matrix inequality (LMI) and finite-time stability theory. Finally, numerical simulations are given to verify the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

In compressed sensing (CS), sparse or compressible signals can be reconstructed with fewer samples than the Nyquist–Shannon theorem requires. Over the past ten years, CS has developed into a relatively mature theory and this brand-new technique has been widely used in many fields such as image processing, wireless communication and medical imaging. In this paper, we propose a new model for signal compression and reconstruction based on semi-tensor product, called STP-CS, which is a generalization of traditional CS. Like traditional CS, we investigate some reconstruction conditions of STP-CS in terms of the spark, the coherence and the restricted isometry property (RIP). The experimental results show that STP-CS has the flexibility to choose a lower-dimensional sensing matrix for signal compression and reconstruction. [ABSTRACT FROM AUTHOR]

For the reason that the uncertain complex dynamic network with multi-link is quite close to various practical networks, there is superiority in the fields of research and application. In this paper, we focus upon pinning adaptive synchronization for uncertain complex dynamic networks with multi-link against network deterioration. The pinning approach can be applied to adapt uncertain coupling factors of deteriorated networks which can compensate effects of uncertainty. Several new synchronization criterions for networks with multi-link are derived, which ensure the synchronized states to be local or global stable with uncertainty and deterioration. Results of simulation are shown to demonstrate the feasibility and usefulness of our method. [ABSTRACT FROM AUTHOR]

Highlights: [•] We find that spatial arrangements of coupling strength have great impacts on the synchronizability. [•] The coupling mismatch between two neighor nodes exponentially decreases the synchronizability. [•] When the coupling strength are spatially rearranged,the synchronizability obey a log-normal distribution. [•] The spatial arrangement of period 1 achieves the best synchronizability while that of period 2 has the worst one. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel design method for determining the optimal PID controller parameters of an automatic voltage regulator (AVR) system using the chaotic ant swarm (CAS) algorithm. In the tuning process of parameters, the CAS algorithm is iterated to give the optimal parameters of the PID controller based on the fitness theory, where the position vector of each ant in the CAS algorithm corresponds to the parameter vector of the PID controller. The proposed CAS-PID controllers can ensure better control system performance with respect to the reference input in comparison with GA-PID controllers. Numerical simulations are provided to verify the effectiveness and feasibility of PID controller based on CAS algorithm. [Copyright &y& Elsevier]