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The parallel computing power of quantum computing and the special properties of qubits provide an effective solution for image processing tasks. This paper presents a quantum image encryption algorithm based on Fisher–Yates algorithm and Logistic mapping. Firstly, the Fisher–Yates algorithm is used to generate three key sequences, one of which is used to encode the coordinate qubits of the image. Using the other two keys and the preset rules, the quantum coordinate scrambling operation is designed based on the encoded coordinate qubit, which effectively scrambles the spatial information of the plaintext image. Next, another set of key sequences is generated, one of which is used to encode the color qubits of the image. Using two other key sequences and different rules, a qubit plane scrambling operation based on coded color qubits is designed, and the color information of image is scrambled successfully. Finally, the quantum key image is generated based on Logistic mapping, and the key image is scrambled based on Fisher–Yates algorithm to improve the key complexity. The final ciphertext image is obtained by performing XOR operation between the original image and the scrambled key image. The complete quantum circuit diagram of the scheme is given in this paper. The experimental results and security analysis prove the effectiveness of the scheme, which provides a large key space and the computational complexity is only O(n). [ABSTRACT FROM AUTHOR]

This paper aims to globally solve a generalized affine fractional program problem (GAFPP). Firstly, by introducing some outer space variables and performing equivalent transformations, we can derive the equivalence problem (EP) of the GAFPP. Secondly, by constructing a novel linear relaxation method, we can deduce the affine relaxation problem (ARP) of the EP. Next, by solving the ARP to compute the lower bound, we propose a new outer space branch-and-bound algorithm for tackling the GAFPP. Then, the global convergence of the algorithm is proved, and the computational complexity of the algorithm in the worst case is analyzed. Finally, numerical experimental results are reported to illustrate the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

In this paper we study the computational complexity issues of the problem of secondary domination (known also as (1, 2)-domination) in several graph classes. We also study the computational complexity of the problem of determining whether the domination and secondary domination numbers are equal. In particular, we study the influence of triangles and vertices of degree 1 on these numbers. Also, an optimal algorithm for finding a minimum secondary dominating set in trees is presented. [ABSTRACT FROM AUTHOR]

This paper constructs an interval partition linearization algorithm for solving minimax linear fractional programming (MLFP) problem. In this algorithm, MLFP is converted and decomposed into a series of linear programs by dividing the outer 1-dimensional space of the equivalent problem (EP) into polynomially countable intervals. To improve the computational efficiency of the algorithm, two new acceleration techniques are introduced, in which the regions in outer space where the optimal solution of EP does not exist are largely deleted. In addition, the global convergence of the proposed algorithm is summarized, and its computational complexity is illustrated to reveal that it is a fully polynomial time approximation scheme. Finally, the numerical results demonstrate that the proposed algorithm is feasible and effective. [ABSTRACT FROM AUTHOR]

Online streaming feature selection (OSFS) methods are used to dynamically update the feature space as well as remove irrelevant and redundant features from the data. Since most Big Data in real-world applications are generated in the form of data streams, effective methods should be developed in this area. Further, methods with low computational complexity are required to make online decisions. In this paper, the OSFS process is modeled as a multi-objective optimization problem. To the best of our knowledge, this is the first time that the concept of Pareto dominance has been applied to find the optimal subset of features in OSFS. When a new feature arrives, it is evaluated in the multi-objective space. The non-dominated features are the optimal subset for each timestamp. We proposed an efficient and effective method which enhances the classification accuracy in OSFS by minimizing the number of features within a short time. In addition, the proposed method is insensitive to the feature streams. Experiments are conducted using two classifiers and seven OSFS methods, including OSFSMI, K-OFSD, OFS-A3M, OFS-Density, Alpha-Investing, SAOLA, and OFSS-FI. [ABSTRACT FROM AUTHOR]

In practical applications, the optimal solutions of multi-objective optimization are not unique. Some problems exist different Pareto Sets (PSs) in the decision space mapped to the same Pareto Front (PF) in the objective space, which are called multimodal multi-objective problems (MMOPs). To tackle this issue, this paper proposes a multimodal multi-objective optimization based on a local optimal neighborhood crowding distance differential evolution algorithm. First, an adaptive partitioning strategy in the initialization phase is proposed by using the characteristics of the heuristic stochastic search. That ensures the local optimal solution is quickly found among multiple PSs. Second, opposition-based learning is combined with differential mutation to generate vectors, which accelerate the convergence of the population to the optimal solution. Finally, a method for neighborhood crowding distances on different Pareto ranks is designed. The distance is computed by a weighted sum of Euclidean distances for the nearest neighbors. While reducing computational complexity, this strategy reflects realistic crowding degree. With these methods, balances the diversity performance of the decision and the objective space, while improving the search capability. Multiple PSs reveal the problem's potential characteristics and meet the needs of the decision-maker. The practical significance is verified by the application of actual distance minimization problem. According to experimental results, the proposed method can achieve a high level of comprehensive performance. [ABSTRACT FROM AUTHOR]

In the paper we investigate Two Sets Intersection problem. Assume that we have two sets that are subsets of n objects. Sets are presented by two predicates that show which of n objects belong to these sets. We present a quantum algorithm that finds an element from the two sets intersection. It is a modification of the well-known Grover's search algorithm that uses two Oracles with access to the predicates. The algorithm is faster than the naive application of Grover's search. [ABSTRACT FROM AUTHOR]

Image stitching is a fundamental pillar of computer vision, and its effectiveness hinges significantly on the quality of the feature descriptors. However, the existing feature descriptors face several challenges, including inadequate robustness to noise or rotational transformations and limited adaptability during hardware deployment. To address these limitations, this paper proposes a set of feature descriptors for image stitching named Lightweight Multi-Feature Descriptors (LMFD). Based on the extensive extraction of gradients, means, and global information surrounding the feature points, feature descriptors are generated through various combinations to enhance the image stitching process. This endows the algorithm with formidable rotational invariance and noise resistance, thereby improving its accuracy and reliability. Furthermore, the feature descriptors take the form of binary matrices consisting of 0s and 1s, not only facilitating more efficient hardware deployment but also enhancing computational efficiency. The utilization of binary matrices significantly reduces the computational complexity of the algorithm while preserving its efficacy. To validate the effectiveness of LMFD, rigorous experimentation was conducted on the Hpatches and 2D-HeLa datasets. The results demonstrate that LMFD outperforms state-of-the-art image matching algorithms in terms of accuracy. This empirical evidence solidifies the superiority of LMFD and substantiates its potential for practical applications in various domains. [ABSTRACT FROM AUTHOR]

Wideband linear frequency modulation (LFM) signals are widely used in radar, sonar, mobile, and similar applications. One of the common problems of algorithms for estimating the direction of arrival (DOA) of LFM signals is that the number of snapshots must be large for good estimation. Therefore, they are not suitable for real-time and low-power applications. In this paper, we proposed a method of estimating DOA based on the sparse iterative covariance (SPICE) algorithm, which has features such as low computational complexity for the uniform linear array (ULA) using the Fourier transform (FFT). We first developed the dechirp process for linear frequency modulation signals using the Fourier transform. Then we modified the SPICE algorithm for linear arrays. Finally, we have obtained the calculation of the DOA estimation for a few snapshots with low computational complexity and high resolution. Compared to other methods, the simulation results of the proposed LSPICE algorithm show an increase in estimation accuracy, higher resolution, more acceptable accuracy in low SNRs, less error in high SNRs, favorable response with low snapshots, and lower computational complexity. [ABSTRACT FROM AUTHOR]

This paper proposes an accelerating outer space algorithm for globally solving generalized linear multiplicative problems (GLMP). Utilizing the logarithmic and exponential function properties, we begin with transforming the GLMP into an equivalent problem (EP) by introducing some outer space variables. Then, a two-stage outer space relaxation method is developed to convert the EP into a series of relaxed linear problems. Furthermore, to improve the convergence speed of the algorithm, we develop some accelerating techniques to remove the domains that do not contain a global optimal solution. Then, fusing the linear relaxed method and accelerating techniques into the branch-and-bound framework, we provide the accelerating outer space algorithm for solving the EP. Additionally, we analyze the global convergence of the proposed algorithm. Meanwhile, by investigating the algorithmic complexity, we estimate the maximum iterations required by the proposed algorithm in the worst case. Finally, in contrast to other algorithms in the currently known literature, numerical experimental results indicate that the proposed algorithm is feasible with better efficiency and robustness. [ABSTRACT FROM AUTHOR]

The attribute-based encryption (ABE) scheme is suitable for access control of ciphertext in cloud computing. Kowalczyk and Wee proposed an adaptively secure attribute-based encryption scheme that supports NC 1 circuits. However, the ciphertext length increases rapidly with the depth of the circuit, resulting in an increase of the computational complexity of the encryption and decryption algorithms. In this paper, to overcome this challenge, a ciphertext-policy ABE scheme that supports circuits with fan-in n is proposed. First, we design new pebble rules for secret sharing in circuits with fan-in n, improving the compactness of the security reduction. Then, the new secret sharing scheme is embedded in the encryption algorithm, which is the key to improving efficiency. Moreover, we prove the adaptive security of the scheme by using a piecewise guessing framework and dual-system encryption. Finally, by comparison analysis, this scheme exhibits a better performance. [ABSTRACT FROM AUTHOR]

In this paper, we address the issue of solving problems with multiple components, multiple objectives, and target values for each objective. There are limitations in managing these multi-component, multi-goal problems such as the need for domain expertise to combine or prioritize the goals. In this paper, we propose a domain-independent method, Adaptive Leveling-Weighting-Clustering (ALWC), to manage the exploration of design scenarios of multi-goal, engineering-design problems. Using ALWC, designers explore combinations and priorities of the goals based on their interrelationships. Through iteration, design scenarios are obtained with higher goal achievements and an improved understanding of the relationship among subsystems. This is achieved without increasing computational complexity. This knowledge is helpful for multi-component design. The ALWC method is demonstrated using a thermal-system design problem. [ABSTRACT FROM AUTHOR]

Image saliency detection is a process for highlighting the most salient object in an image and presenting the image saliency map. The content of an image is chaotic, including a complex background, low contrast, and an irregular salient object appearance. To overcome these problems, many algorithms have high computational complexity. In this paper, an efficient and fast-performing saliency detection algorithm is proposed, which consists of initiation saliency map generation and saliency map refinement. In the generation stage, the color-based contrast prior and color-based spatial distribution prior are effectively described in the image. Subsequently, two prior results (contrast value and distribution value) are fused to obtain an initial saliency map. In the refinement stage, the initial saliency map is refined by visual focus and an adaptive salient object mask (SOM). Due to the simplicity of the proposed algorithm, the system can detect salient objects in real time. Experimental evaluation on the benchmark shows that the proposed method can achieve sufficient accuracy and reliability while showing the lowest execution time. Compared with other methods, the execution time of the proposed method can achieve 137 frames per second (FPS) for the dataset with average image size 386 × 292. [ABSTRACT FROM AUTHOR]

360-degree videos have become increasingly popular with the application of virtual reality (VR) technology. To encode such kind of videos with ultra-high resolution, an efficient and real-time video encoder becomes a key requirement. The Versatile Video Coding (VVC) standard has good coding performance. However, it has pretty high computational complexity which increasing the application cost of 360-degree videos. Among them, the decision of the quadtree with nested multi-type tree (QTMT) partitioning structure is one of the time-consuming procedures. In this paper, based on the characteristics of 360-degree video with Equirectangular projection (ERP) format, the empirical variogram combined with Mahalanobis distance is introduced to measure the difference between the horizontal and vertical directions of the CU, and a fast partition algorithm is proposed. The experimental results show that the algorithm saves 32.13% of the coding time with only an increase of 0.66% in BDBR. [ABSTRACT FROM AUTHOR]

Overlapping community detection with low computation is one of the fundamental issues and challenges in large-scale complex network analysis. Detecting a community in a network means discovering a cluster of network nodes so that the density of edges between them is high. The existing methods use entire structure information or subgraphs with a fixed size to detect dense communities. Therefore, they are not efficient and accurate for large-scale networks. In this paper, the authors introduce an overlapping community detection algorithm that gradually improves density estimation by expanding the size of subgraphs and gathering information during the search process for finding communities. It is an efficient algorithm with low computational complexity for complex networks with one hundred thousand to several millions of nodes. Experimental results on synthetic and real-world networks with several hundred to four million nodes validate the performance assessment of the proposed method. [ABSTRACT FROM AUTHOR]

A spectral power-based real-time BCI neuro-feedback (decision machine) system has been proposed in this paper. It is used to reflect the intended task of the movement imagination of hand movements. As a consequence of the cost-effective and greater temporal resolution, the proposed decision machine considered the electroencephalogram (EEG) signal. EEG data modeling is therefore an important step in seeking a rational solution for a specific application. The most potential temporal relative spectral power (TRSP) based feature extraction algorithm, and probabilistic Bayesian classifier has been used to model the EEG data for the reproduction of the thoughts. In this paper, the author has considered two channels of information for command generation. This paper also focuses on the maximization of information retrieval by analyzing incoming two channels' brain signals. This initiates to devise an appropriate reactive frequency band for each subject before applying the feature extraction algorithm. In this direction, this paper uses relative power spectral intensity (RPSI) for reactive frequency band estimation. The spectral power-based feature extraction method is responsible for the improvement of the accuracy, reducing the computational complexity, lowers the computational time, and improves the information transfer rate. The performance of the proposed BCI system shows better results compared to the different well established conventional EEG based BCI systems. The proposed real-time neuro-feedback system is a generalized BCI system that will be readily applicable for controlling any external devices. The proposed system shows 90.37% accuracy over the BCI Competition II dataset and 81% average accuracy with 64 ms computational time in the real-time application. [ABSTRACT FROM AUTHOR]

In this paper, a fast template matching algorithm of two-stage and dual-check bounded partial correlation (TDBPC) based on normalized cross-correlation (NCC) of single-check bounded partial correlation is proposed. According to the principle of continuous rows, the template and the sub-image under matching are divided into three subregions to obtain two upper boundary terms of NCC and get two checking conditions then. In this way, it is possible to quickly eliminate matching points that cannot provide a better cross-correlation score regarding the current best candidate. Generally, to get the highest cross-correlation score, the sub-image has to traverse through the whole image. In addition, the two-stage search strategy of coarse–fine proposed in this paper can further reduce the calculation and improve matching efficiency. The initialization parameters are selected experimentally or automatically. Experimental results show that the TDBPC algorithm proposed in this paper can solve high computational complexity and long matching time of NCC template matching and make it possible to achieve real-time template matching in industrial vision positioning fields. The feasibility of this algorithm in practical application is proved. [ABSTRACT FROM AUTHOR]

The generalized variable step-size diffusion continuous mixed p-norm (GVSS-DCMPN) algorithm is proposed in this paper, which is derived based on the improved continuous mixed p-norm (CMPN) strategy. In detail, a linear function is designed for the CMPN strategy. The proposed GVSS-DCMPN algorithm capable of exploiting various error norms to obtain performance improvement in non-Gaussian noise environment can be viewed as the generalization of the traditional p-norm-based algorithms in the sense of continuous errors. In particular, the GVSS-DCMPN algorithm transforms into the VSS-DCMPN algorithm when the slope of the linear function is set to 0. The computational complexity as well as the mean convergence is analyzed in the paper. Simulation results over the diffusion network show that the proposed algorithm achieves performance gain over some existing diffusion algorithms. [ABSTRACT FROM AUTHOR]

While k-anonymous algorithms can effectively protect users' private location information, the problem of selecting an appropriate location in the anonymous area to construct the k-anonymous area remains a significant one. When selecting real users from the surrounding area to co-construct anonymous regions, it is easy to cause the leakage of user location information. Moreover, using false addresses to construct a region requires calculating the probability of location queries, which increases the computational complexity. In this paper, an all-dummy k-anonymous algorithm based on location offset is proposed to construct anonymous regions. This algorithm randomly selects k−1 locations and real users in the selected anonymous compose an anonymous group at first. Subsequently, these coordinates are centered on migration, generating multiple dummy addresses of each location migration, such that the dummy address distance is greater than the radius of the user's query, with the dummy address location information used for the location server queries. Through experimental verification, compared with the circle-based dummy address generation algorithm and the random k-anonymous algorithm, the all-dummy k-anonymous algorithm is found to achieve an entropy value and tracking success rate closer to the optimal k-anonymous algorithm without increasing the communication cost. [ABSTRACT FROM AUTHOR]

In 2016, Karney proposed an exact sampling algorithm for the standard normal distribution. In this paper, we study the computational complexity of this algorithm under the random deviate model. Specifically, Karney's algorithm requires the access to an infinite sequence of independently and uniformly random deviates over the range (0, 1). We give a theoretical estimate of the expected number of uniform deviates used by this algorithm until it completes, and present an improved algorithm with lower uniform deviate consumption. The experimental results also shows that our improved algorithm has better performance than Karney's algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we propose to use Artificial Bee Colony (ABC) optimization to solve the joint mode selection, channel assignment, and power allocation (JMSCPA) problem to maximize system throughput and spectral efficiency. JMSCPA is a problem where the allocation of channel and power depends on the mode selection. Such problems require two step solution and are called bi-level optimization problems. As bi-level optimization increases the complexity and computational time, we propose a modified version of single-level ABC algorithm aided with the adaptive transmission mode selection algorithm to allocate the cellular, reuse, and dedicated modes to the DUs along with channel and power allocation based on the network traffic load scenarios. A single variable, represented by the users (CUs and DUs) is used to allocate mode selection, and channel allocation to solve the JMSCPA problem, leading to a simpler solution with faster convergence, and significant reduction in the computational complexity which scales linearly with the number of users. Further, the proposed solution avoids premature stagnation of conventional ABC into local minima by incorporating a modification in its update procedure. The efficacy of the ABC-aided approach, as compared to the results reported in the literature, is validated by extensive numerical investigations under different simulation scenarios. [ABSTRACT FROM AUTHOR]

The cluster-sparse proportionate affine projection algorithm (CS-PAPA) exhibits a good solution for estimating the unknown echo path in network echo cancellation. However, the algorithm does not take into account the past proportionate factors for updating the filter coefficients. In this paper, a modification to the CS-PAPA is proposed in the context of echo cancellation. The proposed algorithm named memory cluster-sparse proportionate affine projection algorithm (MCS-PAPA) incorporates the history of proportionate factors into the CS-PAPA. Based on the energy conservation arguments, a rigorous performance analysis of the proposed algorithm is presented, which expresses the steady-state mean square error in terms of the projection order and other parameters. Moreover, the condition for the mean stability is derived. Experimental results for the steady-state mean square error corroborate with the theoretical expressions. Simulation experiments show that the proposed algorithm outperforms some existing algorithms in terms of normalised misalignment, convergence rate, and tracking. As the history of proportionate gain elements is included recursively, the proposed algorithm also exhibits a reduction in computational complexity in terms of the number of multiplications required. [ABSTRACT FROM AUTHOR]

With low hardware cost and power consumption, direction-of-arrival (DOA) estimation exploiting one-bit quantized array data has become an attractive topic. In this paper, the gridless compressed sensing (CS) with multiple measurement vectors for one-bit DOA estimation is investigated. First, the one-bit quantized signal model is established. Then an atomic norm minimization scheme is proposed based on the output of one-bit quantizer, in which the objective function is reformulated as a semidefinite programming problem combined with a one-sided l 1 -norm constraint, representing the sign inconsistency between the quantized and unquantized measurements. To efficiently solve such a problem and reduce its computational complexity, an accelerated proximal gradient-based algorithm is developed. The proposed approach outperforms the one-bit MUSIC in a small number of measurements, and avoids the grid-mismatch issue of several existing one-bit CS methods. Numerical experiments are conducted to validate the superiorities of the proposed one-bit DOA estimation approach in accuracy and running time. [ABSTRACT FROM AUTHOR]

Virtual machine abnormal behavior detection is an effective way to help cloud platform administrators monitor the running status of cloud platform to improve the reliability of cloud platform, which has become one of the research hotspots in the field of cloud computing. Aiming at the problems of high computational complexity and high false alarm rate in the existing virtual machine anomaly monitoring mechanism of cloud platform, this paper proposed a two-stage virtual machine abnormal behavior-based detection mechanism. Firstly, a workload-based incremental clustering algorithm is used to monitor and analyze both the virtual machine workload information and performance index information. Then, an online anomaly detection mechanism based on the incremental local outlier factor algorithm is designed to enhance detection efficiency. By applying this two-phase detection mechanism, it can significantly reduce the computational complexity and meet the needs of real-time performance. The experimental results are verified on the mainstream Openstack cloud platform. [ABSTRACT FROM AUTHOR]

Network Function Virtualization (NFV) is a vital player of modern networks providing different types of services such as traffic optimization, content filtering, and load balancing. More precisely, NFV is a provisioning technology aims at reducing the large Capital Expenditure (CapEx) of network providers by moving services from dedicated hardware to commodity servers using Virtualized Network Functions (VNF). A sequence of VNFs/services following a logical goal is referred to as a Service Function Chain (SFC). The movement toward SFC introduces new challenges to those network services which require high reliability. To address this challenge, redundancy schemes are introduced. Existing redundancy schemes using dedicated protection enhance the reliability of services, however, they do not consider the cost of redundant VNFs. In this paper, we propose a novel reliability enhancement method using a shared protection scheme to reduce the cost of redundant VNFs. To this end, we mathematically formulate the problem as a Mixed Integer Linear Programming (MILP). The objective is to determine optimal reliability that could be achieved with minimum cost. Although the corresponding optimization problem can be solved using existing MILP solvers, the computational complexity is not rational for realistic scenarios. Thereafter, we propose a Reliability-aware and minimum-Cost based Genetic (RCG) algorithm to solve this problem with low computational complexity. In order to evaluate the proposed solution, we have compared it with four different solutions. Simulation results show that RCG achieves near-optimal performance at a much lower complexity compared with the optimal solution. [ABSTRACT FROM AUTHOR]

A filtering algorithm based on frequency domain spline type, frequency domain spline adaptive filters (FDSAF), effectively reducing the computational complexity of the filter. However, the FDSAF algorithm is unable to suppress non-Gaussian impulsive noises. To suppression non-Gaussian impulsive noises along with having comparable operation time, a maximum correntropy criterion (MCC) based frequency domain spline adaptive filter called frequency domain maximum correntropy criterion spline adaptive filter (FDSAF-MCC) is developed in this paper. Further, the bound on learning rate for convergence of the proposed algorithm is also studied. And through experimental simulations verify the effectiveness of the proposed algorithm in suppressing non-Gaussian impulsive noises. Compared with the existing frequency domain spline adaptive filter, the proposed algorithm has better performance. [ABSTRACT FROM AUTHOR]

This paper aims to extend the proportionate adaptation concept to the design of a class of diffusion normalized subband adaptive filter (DNSAF) algorithms. This leads to four extensions of the algorithm associated with different step-size variations, namely diffusion proportionate normalized subband adaptive filter (DPNSAF), diffusion μ -law PNSAF (DMPNSAF), diffusion improved PNSAF (DIPNSAF) and diffusion improved IPNSAF (DIIPNSAF). Subsequently, steady-state performance, stability conditions and computational complexity of the proposed algorithms are investigated. For each extension the performance has been evaluated using both real and simulated data, where the outcomes demonstrate the accuracy of the theoretical expressions and effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]

This paper proposes a fast and accurate computational framework for scale-aware image filters. Our framework is based on accurately approximating L 1 Gaussian convolution with respect to a transformed pixel domain representing geodesic distance on a guidance image manifold in order to recover salient edges in a manner faithful to scale-space theory while removing small image structures. Our framework possesses linear computational complexity with high approximation precision. We examined it numerically in terms of speed, accuracy, and quality compared with conventional methods. [ABSTRACT FROM AUTHOR]

In this paper, the problem of load uncertainty in compliance problems is addressed where the uncertainty is described in the form of a set of finitely many loading scenarios. Computationally, more efficient methods are proposed to exactly evaluate and differentiate: (1) the mean compliance or (2) any scalar-valued function of the individual load compliances such as the weighted sum of the mean and standard deviation. The computational time complexities of all the proposed algorithms are analyzed, compared with the naive approaches and then experimentally verified. Finally, a mean compliance minimization problem, a risk-averse compliance minimization problem, and a maximum compliance-constrained problem are solved to showcase the efficacy of the proposed algorithms. The maximum compliance-constrained problem is solved using the augmented Lagrangian method and the method proposed for handling scalar-valued functions of the load compliances, where the scalar-valued function is the augmented Lagrangian function. [ABSTRACT FROM AUTHOR]

Sinusoidal model and chirp model are the two fundamental models in digital signal processing. Recently, a chirp-like model was introduced by Grover et al. (International conference on computing, power and communication technologies, IEEE, pp. 1095–1100, 2018). A chirp-like model is a generalization of a sinusoidal model and provides an alternative to a chirp model. We derive, in this paper, the asymptotic properties of least squares estimators and sequential least squares estimators of the parameters of a chirp-like signal model. It is observed theoretically as well as through extensive numerical computations that the sequential least squares estimators perform at par with the usual least squares estimators. The computational complexity involved in the sequential algorithm is significantly lower than that involved in calculating the least squares estimators. This is achieved by exploiting the orthogonality structure of the different components of the underlying model. The performances of both the estimators for finite sample sizes are illustrated by simulation results. In the specific real-life data analyses of signals, we show that a chirp-like signal model is capable of modeling phenomena that can be otherwise modeled by a chirp signal model, in a computationally more efficient manner. [ABSTRACT FROM AUTHOR]

To better perform distributed estimation, this paper, by combining the Fair cost function and adapt-then-combine scheme at all distributed network nodes, a novel diffusion adaptive estimation algorithm is proposed from an M-estimator perspective, which is called the diffusion Fair (DFair) adaptive filtering algorithm. The stability of the mean estimation error and the computational complexity of the DFair are theoretically analyzed. Compared with the robust diffusion LMS (RDLMS), diffusion Normalized Least Mean M-estimate (DNLMM), diffusion generalized correntropy logarithmic difference (DGCLD), and diffusion probabilistic least mean square (DPLMS) algorithms, the simulation experiment results show that the DFair algorithm is more robust to input signals and impulsive interference. In conclusion, Theoretical analysis and simulation results show that the DFair algorithm performs better when estimating an unknown linear system in the changeable impulsive interference environments. [ABSTRACT FROM AUTHOR]

We consider a non-convex quadratic program (QP) with linear and convex quadratic constraints that arises from a broad range of applications and is known to be NP-hard. In this paper, we first prove that the alternative direction method converges to a local solution of the underlying QP problem. We then propose a new branch-and-cut algorithm that finds a globally optimal solution to the underlying QP problem within a pre-specified 𝜖-tolerance by integrating the alternative direction method with semidefinite relaxation and disjunctive cut techniques. We establish the global convergence of the algorithm and estimate its complexity. Preliminary numerical results demonstrate that the proposed algorithm can effectively find a globally optimal solution to medium-scale QP instances in which the number of negative eigenvalues of the Hessian matrix in the objective function is less than or equals 20. [ABSTRACT FROM AUTHOR]

Cloud computing along with the Internet of Things (IoT) is proving to be an essential tool for delivering better healthcare services. However, maintenance, privacy, confidentiality, and security of Electronic Health Information (EHI) pose a huge challenge in telemedicine. The sharing of EHI with a remote doctor over the cloud is an important issue since the minute variation may lead to the wrong diagnosis. Despite the plethora of research in this field, there is an immense necessity to develop the algorithms for enhancing security in e-healthcare systems. In this paper, an innovative Reversible Data Hiding (RDH) scheme using Lagrange's interpolation polynomial, secret sharing, and bit substitution for EHI security has been proposed. The cover medical image is sub-sampled, into four shares. Image interpolation is used to enlarge the subsamples, for hiding EHI. The secret information is processed using Lagrange's interpolation polynomial before being embedded in the various cover image shares. The data is embedded into the interpolated sub-sampled shares at the locations pre-defined by the algorithm. The distributive nature of embedded data enhances the security of the proposed framework while maintaining reversibility. We show that only 75% of shares are required to obtain the whole embedded data and the undistorted cover image. The proposed scheme outperforms the schemes under comparison in terms of imperceptibility and payload. It can reversibly embed 163,840 bits (0.75 bits per pixel) with an average PSNR of about 52.38 dB. The average values of relative entropy, the difference in relative entropy, standard deviation, and cross-correlation are 7.3242, 0.0382, 65.0539, and 0.9838, respectively, for the first sub-sample. It shows an increase of about 3 dB for a payload of 1, 30,000 bits when compared to the state-of-art. Further, it is pertinent to mention that the proposed scheme has lower computational complexity and is hence useful for e-healthcare applications. Given all the attributes of the scheme along with its lower computational complexity, it is suitable for EHI security in a distributive environment like cloud computing. [ABSTRACT FROM AUTHOR]

Segmentation of image is a key step in image analysis and pre-processing. It consists of separating the pixels into different segments based on their intensity level according to threshold values. The most challenging job in segmentation is to select the optimum threshold values. Standard multilevel thresholding (MT) techniques are effective for bi-level thresholds due to their simplicity, robustness, decreased convergence time and precision. As the level of thresholds increases, computational complexity also increases exponentially. To mitigate these issues various metaheuristic algorithm are applied to this problem. In this manuscript, a new hybrid version of the Dragonfly algorithm (DA) and Firefly Algorithm (FA) is proposed. DA is an optimization algorithm recently suggested based on the dragonfly's static and dynamic swarming behavior. DA's worldwide search capability is great with randomization and static swarm behavior, local search capability is restricted, resulting in local optima trapping alternatives. The firefly algorithm (FA) is influenced by fireflies' social behavior in which they generate flashlights to attract their mates. The suggested technique combines the ability to explore DA and firefly Algorithm's ability to exploit to obtain ideal global solutions. In this paper, HDAFA is applied on ten standard test images having a diverse histogram, which are taken from Berkeley Segmentation Data Set 500 (BSDS500) benchmark image set for segmentation. The search capability of the algorithm is employed with OTSU and Kapur's entropy MT as an objective functions for image segmentation. The proposed approach is compared with the existing state-of-art optimization algorithms like MTEMO, GA, PSO, and BF for both OTSU and Kapur's entropy methods. Qualitative experimental outcomes demonstrate that HDAFA is highly efficient in terms of performance metric such as PSNR, mean, threshold values, number of iterations taken to converge and image segmentation quality. [ABSTRACT FROM AUTHOR]

Aiming at the slow processing speed of classic image encryption algorithms and the security analysis of existing quantum image encryption algorithms, this paper combines the representation method of quantum images and proposes a quantum image encryption algorithm based on image correlation decomposition. Using the principle of quantum state superposition and measurement, the association between image pixels is established, the image is decomposed into a series of feature sub-images and stored in a complete binary tree set, and different sub-images are operated and encrypted by random phase operation and quantum rotation operation. Then superimpose all the sub-images to obtain the ciphertext image. The algorithm has a larger key space so that it can resist brute force attacks. At the same time, the quantum encryption algorithm has lower computational complexity than classic encryption algorithms. In addition, because the ciphertext image is transmitted in the communication channel in the form of a quantum state, the security of quantum image encryption also surpasses the security of classical image encryption. [ABSTRACT FROM AUTHOR]

Existing discriminative correlation filters suffer from the defects of potential spatial distractors and the degradation of appearance model caused by hard-temporal correlation. Aiming at this issue, a robust tracker which combines the adaptive spatial regularization and the temporal consistent constraint is proposed in this paper. First, we propose to take the extracted saliency map of the background as a reference weight to construct the spatial regularization term, with which the perceived performance of the filter against distractors is enhanced by learning the spatial sparse constraint adaptively. Second, we further implement the temporal consistent regularization formed by capturing dynamic appearance information from multiple historical frames with a high-confidence strategy to mitigate the model degradation. Third, we employ the alternating direction method of multipliers to solve the constrained optimization problem efficiently, thereby the computational complexity can be reduced. The concrete experimental results on OTB-2013, OTB-2015, Temple-Color-128 and VOT2016 benchmarks demonstrate that our tracker outperforms several state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

This paper proposes a novel metaheuristic-based optimization technique called search space reduction (SSR) optimization algorithm. This algorithm attempts to solve the common pitfalls in the existing algorithms in the literature by randomly generating the search agents in every iteration instead of following the best solution. This new algorithm is simple, computationally efficient, which is based on the concept of reducing the search space. The performance of this algorithm is tested over classical test functions and CEC'17 benchmark test functions. The results are compared with well-established algorithms in the literature. The test results show that the proposed algorithm exhibits good exploration and exploitation capabilities. Further, this algorithm also outperforms other algorithms in solving multimodal optimization problems. In addition to this, the computational complexity of this algorithm is also presented according to CEC'17 guidelines. The proposed algorithm is also employed to solve three engineering design problems and a more complex re-entry trajectory optimization problem to show its effectiveness. [ABSTRACT FROM AUTHOR]