For the multi-target DOA estimation problem of uniform linear arrays, this paper proposes a method based on deep convolution neural network. The algorithm adopts convolutional network, and array signal is transformed into inverse mapping output covariance matrix to binary sequence in which "1" indicates that there target incident corresponding angular direction at position. upper triangular discrete used as data input realize multiple sources. simulation results show accuracy proposed...

The current common color image encryption algorithms applying “scrambling-diffusion” have some problems, such as the small key space, cumbersome process, and security vulnerability. Aiming at these this paper proposes a new algorithm based on hyperchaotic system “transforming-scrambling-diffusion” model. Before scrambling, in accordance with plaintext itself attributes, number of iterations was calculated, all pixel values were transformed into gray code iteratively, then chaotic sequence...

This paper proposes a joint estimation method for source number and DOA based on an improved convolutional neural network unknown undetermined estimation. By analyzing the signal model, designs model existence of mapping relationship between covariance matrix both The which discards pooling layer to avoid data loss introduces dropout improve generalization, takes as input two branches outputs, achieves unfixed by filling in invalid values. Simulation experiments analysis results show that...

Abstract This letter proposes an efficient tensor model for Direction of Departure (DOD) and Arrival (DOA) estimation based on bistatic nested Multiple‐Input Multiple‐Output (MIMO) radar. Tensor offers a robust solution in characterizing multi‐dimensional data structures, ensuring integrity, has demonstrated remarkable effectiveness the realm parameter estimation. However, complexity traditional methods constructing tensors is major obstacle to practical applications. In response, this...

To understand the origin and early evolution of life it is crucial to establish characteristics primordial environment that facilitated emergence life. One important environmental factor pH environment. Here, we assessed pH-dependent thermal stabilities previously reconstructed ancestral nucleoside diphosphate kinases ribosomal protein uS8s. The selected proteins were likely be present in ancient organisms such as last common ancestor bacteria archaea. We also stability homologous from...

In this advanced exploration, we focus on multiple parameters estimation in bistatic Multiple-Input Multiple-Output (MIMO) radar systems, a crucial technique for target localization and imaging. Our research innovatively addresses the joint of Direction Departure (DOD), Arrival (DOA), Doppler frequency incoherent targets. We propose novel approach that significantly reduces computational complexity by utilizing Temporal-Spatial Nested Sampling Model (TSNSM). methodology begins with...

This paper addresses the problem of two-dimensional direction-of-arrival (2D DOA) estimation low-elevation or non-low-elevation targets using L-shaped uniform and sparse arrays by analyzing signal models’ features their mapping to 2D DOA. proposes a DOA algorithm based on dilated convolutional network model, which consists two components: autoencoder neural network. If there are at low elevation, suppresses multipath outputs new covariance matrix as input directly perform in absence target....

Delay Tolerant Network (DTN) is a new type of network, which different from traditional TCP / IP communication protocol network. It suitable for extreme environment where end-to-end connection cannot be established stably. Firstly, the characteristics and structure DTN are analyzed, then nodes in network also analyzed. Secondly, routing problem explained. Next, classification algorithms some classical introduced. Finally, other problems proposed. The stable operation TCP/IP relies mainly on...

Aiming at low degrees of freedom (DOF) and high mutual coupling (MC) the existing sparse arrays, an enhanced generalized nested array (EGNA) is proposed in this paper. Specifically, adds a single antenna on basis (GNA), difference coprime factors employed as spacing between second subarray additional antenna. Then, values are analyzed detail, which indicates that Yang-NA can be explained special case. Compared with majority EGNA not only has closed-form expressions physical locations,...

This paper studies the task assignment problem in multi-agent field. The maximum number of tasks for a single agent and agents required are taken as objective functions. Considering characteristics air defense unmanned combat agent, Multi-agent allocation model based on improved auction algorithm is established. first step to establish mathematical strategy confirms function. Then, resource utilization efficiency by optimizing algorithm. Finally, simulation experiments prove effectiveness convergence

Zero-Shot Sketch-Based Image Retrieval (ZS-SBIR) is a challenging cross-modal retrieval task. In prior arts, the conducted by sorting distance between query sketch and each image in gallery. However, domain gap zero-shot setting make neural networks hard to generalize. This paper tackles challenges from new perspective: utilizing gallery features. We propose Cluster-then-Retrieve (ClusterRetri) method that performs clustering on images uses cluster centroids as proxies for retrieval....

For the DOA (direction of arrival) estimation a low-elevation-angle target under influence multipath effect, this paper proposes method based on CAE (convolutional autoencoder) and CNN neural network). The algorithm firstly inputs signal covariance matrix array low-elevation containing direct reflected waves into convolutional autoencoder to realize de-multipath, uses spatial features extracted by as input extreme learning machine preclassification waves; results, one branch three parallel...

For task planning of the command and control structure, existing algorithms exhibit low efficiency poor replanning quality under abnormal conditions. Given requirements current accusation architecture, a distributed structure model is built in this paper based on multiagents, which exploits superiority multiagents achieving complex tasks. The concept MultiAgent‐HTN proposed framework. original hierarchical network algorithm optimized, multiagent collaboration framework redefined,...

The image encryption algorithm based on chaotic system has been widely used at present. For this kind of algorithm, the mechanism "scrambling - diffusion" and multiple iterations are mainly adopted. In paper, common one-dimensional logistic mapping is taken as an example to analyze influence number effect. simulation results show that, when only complete operation, except for key space, contribution single diffusion operation effect basically same, no significant encryption. When a employed,...

In view of the fact that dynamic characteristic a single chaotic system is insufficient in image encryption algorithm, time sequence output often not theoretical completely random, but cascade can improve defect. And cascading systems make real value discrete distribution more uniform, has better characteristics. Therefore, this paper proposes an algorithm based on s-l system. Through simulation experiment key sensitivity, histogram, correlation between adjacent elements such as evaluation...

In order to improve the color in process of image transmission security and efficiency, sine chaos mapping Hopfield neural network model is put forward with combination encryption algorithm. Firstly, sinusoidal chaotic adopted scrambling stage reduce high correlation between pixels; secondly, key flow generated by iterative used complete diffusion; then, completed through bit operation; finally, effectiveness algorithm are analyzed. It shown from that result statistical analysis simulation...

In the past, way to manage and control satellite operations was mainly accomplished by planning mission plan in advance through ground.However, current missions are becoming more complex, it is necessary face sudden emergency situations changes operating environment.The management model presents many challenges.This paper takes single-satellite collaborative as satelliteting point, summarizes forecasts research of algorithm, which focuses on status autonomous task scheduling planning,...

Abstract The redundant virtual array elements formed by the sum and difference coarray (SDCA) are always discarded in existing DOA estimation methods, which could cause effective information loss poor performance. In this paper, a new technology based on average processing of is proposed for coprime MIMO radar direction arrival (DOA) estimation. Then, Toeplitz matrix reconstruction MUSIC algorithm employed to validate effectiveness

According to the problems of traditional image encryption algorithm, such as cumbersome process, small keyspace, and insufficient security, a color algorithm based on four-dimensional hyperchaotic system using “conversion-scrambling-diffusion” mode is used. The utilizes improved Chen’s system. First, according correlation attribute, gray code iteration number was calculated, inversely transformed pixel value. Subsequently, chaotic sequence generated by used convert converted matrix. global...

According that the current color image encryption algorithms of "scrambling -diffusion" mode have many problems, such as small key space, tedious process, security vulnerability and so on, this paper proposes a new algorithm based on hyperchaotic system, which adopts "transforming -scrambling model.Before scrambling, in accordance with itself attributes, number iterations is calculated, all pixel values gray code iterative transformation, then chaotic sequence generated from four-dimensional...

As a critical target localization and imaging technology, multiple parameters estimation is an important research direction based on bistatic Multiple-Input Multiple-Output (MIMO) radar. This concentrates the Direction of Departure (DOD), Arrival (DOA), Doppler frequency joint incoherent targets. Furthermore, we design effective technique to decrease complexity when computing angles Temporal-spatial Nested Sampling signal model. First, it introduces multi-linear mapping mechanism efficiently...

In this article, we focus on addressing the problem of DOD, DOA, and Doppler Frequency estimation with co-prime MIMO radar. Traditional spatial-temporal smoothing methods suffer from high operational complexity poor algorithm timeliness when overcoming inability a single snapshot virtual signal to be eigenvalue decomposed due rank loss problem. This drawback is particularly evident in process joint multi-dimensional parameter estimation. We first perform sampling received based array then...

Abstract To understand the origin and early evolution of life it is crucial to establish characteristics primordial environment that facilitated emergence life. One importantenvironmental factor pH environment. Here, we assessed pH-dependent thermal stabilities previously reconstructed ancestral nucleoside diphosphate kinases ribosomal protein uS8s. The selected proteins were likely be present in ancient organisms such as last common ancestor bacteria archaea. We also stability homologous...