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Validation method for simulation models with cross iteration

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Journal of Systems Engineering and Electronics 2019年第3期30卷 555-563页

作者： FANG Ke ZHAO Kaibin zhou yuchen Control and Simulation Center Harbin Institute of Technology

Cross iteration often exists in the computational process of the simulation models, especially for control models. There is a credibility defect tracing problem in the validation of models with cross iteration. In order to resolve this problem, after the problem formulation, a validation theorem on the cross iteration is proposed, and the proof of the theorem is given under the cross iteration circumstance. Meanwhile, applying the proposed theorem, the credibility calculation algorithm is provided, and the solvent of the defect tracing is explained. Further, based on the validation theorem on the cross iteration, a validation method for simulation models with the cross iteration is proposed, which is illustrated by a flowchart step by step. Finally, a validation example of a sixdegree of freedom (DOF) flight vehicle model is provided, and the validation process is performed by using the validation method. The result analysis shows that the method is effective to obtain the credibility of the model and accomplish the defect tracing of the validation.

关键词： validation method simulation model cross iteration validation theorem validation example

Resource Trading and Miner Competition in Wireless Blockchain Networks with Edge Computing

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China Communications 2023年第11期20卷 187-201页

作者： yuchen zhou Jian Chen Lu Lyu Bingtao He The State Key Laboratory of Integrated Service Networks Xidian UniversityXi’an 710071China

To promote the application of edge com-puting in wireless blockchain networks,this paper presents a business ecosystem,where edge comput-ing is introduced to assist blockchain users in imple-menting the mining *** paper exploits re-source trading and miner competition to enable se-cure and efficient transactions in the presented busi-ness *** resource trading problem is for-mulated as a Stackelberg game between miner candi-dates and edge computing servers,where computing,caching,and communication resources are jointly op-timized to maximize the potential *** of-floading is introduced to further enhance the system performance when compared with the existing *** analyze the existence and uniqueness of the Nash equilibrium and Stackelberg *** on the optimization result,winners are selected from the set of miner candidates by bidding and constitute the mining *** results demonstrate that the proposal is able to improve the social welfare of blockchain miners,thus stimulating more blockchain users to join the mining network.

关键词： blockchain edge computing miner com-petition resource trading social welfare

Secure coordinated direct and untrusted relay transmissions via interference engineering

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Science China(Information Sciences) 2022年第8期65卷 213-227页

作者： Lu LV Zan LI Haiyang DING yuchen zhou Jian CHEN State Key Laboratory of Integrated Services Networks Xidian University National Mobile Communications Research Laboratory Southeast University School of Information and Communications National University of Defense Technology

This paper investigates the physical layer security issue of the coordinated direct and untrusted relay transmissions, considering both uplink and downlink scenarios. To effectively prevent the untrusted relay from eavesdropping on the confidential information it receives, two novel interference-assisted jamming schemes are proposed, where the inter-user interference and the artificial noise are intelligently engineered to degrade the signal reception quality at the untrusted relay, therefore enhancing the physical layer security for the uplink and downlink coordinated transmission, respectively. For each of the two proposed jamming schemes, a lower bound for the ergodic secrecy sum rate(ESSR) is derived in closed form to evaluate the secrecy performance. To obtain more system design insights, we further provide an asymptotic analysis for the ESSR scaling laws over the regimes of the high signal-to-noise ratio and a large number of antennas at the base-station. We carry out computer simulations to confirm the accuracy of the derived theoretical *** simulation results show that the proposed jamming schemes achieve a similar asymptotic performance limit to the case of using a trusted relay. Moreover, the proposed jamming schemes guarantee perfect security for both uplink and downlink coordinated transmissions, and yield a significant ESSR improvement compared with three other baseline schemes.

关键词： physical layer security untrusted relay interference exploitation coordinated transmission ergodic secrecy rate

Attention-Enhanced Voice Portrait Model Using Generative Adversarial Network

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Computers, Materials & Continua 2024年第4期79卷 837-855页

作者： Jingyi Mao yuchen zhou YifanWang Junyu Li Ziqing Liu Fanliang Bu School of Information Network Security People’s Public Security University of ChinaBeijing100038China

Voice portrait technology has explored and established the relationship between speakers’ voices and their facialfeatures, aiming to generate corresponding facial characteristics by providing the voice of an unknown *** to its powerful advantages in image generation, Generative Adversarial Networks (GANs) have now beenwidely applied across various fields. The existing Voice2Face methods for voice portraits are primarily based onGANs trained on voice-face paired datasets. However, voice portrait models solely constructed on GANs facelimitations in image generation quality and struggle to maintain facial similarity. Additionally, the training processis relatively unstable, thereby affecting the overall generative performance of the model. To overcome the abovechallenges,wepropose a novel deepGenerativeAdversarialNetworkmodel for audio-visual synthesis, namedAVPGAN(Attention-enhanced Voice Portrait Model using Generative Adversarial Network). This model is based ona convolutional attention mechanism and is capable of generating corresponding facial images from the voice ofan unknown speaker. Firstly, to address the issue of training instability, we integrate convolutional neural networkswith deep GANs. In the network architecture, we apply spectral normalization to constrain the variation of thediscriminator, preventing issues such as mode collapse. Secondly, to enhance the model’s ability to extract relevantfeatures between the two modalities, we propose a voice portrait model based on convolutional attention. Thismodel learns the mapping relationship between voice and facial features in a common space from both channeland spatial dimensions independently. Thirdly, to enhance the quality of generated faces, we have incorporated adegradation removal module and utilized pretrained facial GANs as facial priors to repair and enhance the clarityof the generated facial images. Experimental results demonstrate that our AVP-GAN achieved a cosine similarity of0.511, ou

关键词： Cross-modal generation GANs voice portrait technology face synthesis

Photocrosslinkable human amniotic membrane hydrogel for recovery from spinal cord injury

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Bio-Design and Manufacturing 2024年第6期7卷 1035-1052页

作者： Tao Xu Changwei Yang Yang Lu Heng Wang Cheng Chen yuchen zhou Xiaoqing Chen Department of Spine Surgery Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong 226001China

The recovery and reconstruction of central nervous system function after spinal cord injury(SCI)is a worldwide *** difficulty lies in the feasibility issue of new axons passing through the injured area and the negative effect of scarring after *** a biological material,the human amniotic membrane(HAM)has the advantages of protecting nerve growth,inhibiting scar formation,and promoting neovascularization,but its weak physical properties are difficult to apply in treating *** this study,HAMs were first decellularized and then chemically grafted with methacrylic ***,the composite was photocrosslinked with gelatin methacrylate to prepare a cross-network biological *** final complexes prepared by appeal were used for in vitro and in vivo studies of SCI in rats,*** the in vitro experiment,the composite scaffold inherited abundant biological factors from the amniotic membrane and had the physical properties of a hydrogel,thus providing a favorable environment for the growth and development of neurons and blood *** the in vivo experiment,the composite reduced scarring and promoted the growth of new ***,the composite scaffolds can stably simulate the extracellular microenvironment in SCI defects,regulate pathological changes,and promote the generation of new ***,decellularized HAM hydrogels are promising biocomposite materials for central nerve repair after SCI.

关键词： Spinal cord injury Nerve regeneration Human acellular amniotic membrane Composite hydrogel Biological materials

ICMPTend: Internet Control Message Protocol Covert Tunnel Attack Intent Detector

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Computers, Materials & Continua 2022年第5期71卷 2315-2331页

作者： Tengfei Tu Wei Yin Hua Zhang Xingyu Zeng Xiaoxiang Deng yuchen zhou Xu Liu State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China State Key Laboratory of Cryptology Beijing100878China National Computer Network Emergency Response Technical Team/Coordination Center of China 100029China Pennsylvania State University State College16801USA

The Internet Control Message Protocol(ICMP)covert tunnel refers to a network attack that encapsulates malicious data in the data part of the ICMP protocol for *** concealment is stronger and it is not easy to be *** detection methods are detecting the existence of channels instead of clarifying specific attack *** this paper,we propose an ICMP covert tunnel attack intent detection framework ICMPTend,which includes five steps:data collection,feature dictionary construction,data preprocessing,model construction,and attack intent *** can detect a variety of attack intentions,such as shell attacks,sensitive directory access,communication protocol traffic theft,filling tunnel reserved words,and other common network *** extract features from five types of attack intent found in ICMP *** build a multi-dimensional dictionary of malicious features,including shell attacks,sensitive directory access,communication protocol traffic theft,filling tunnel reserved words,and other common network attack *** the high-dimensional and independent characteristics of ICMP traffic,we use a support vector machine(SVM)as a multi-class *** experimental results show that the average accuracy of ICMPTend is 92%,training ICMPTend only takes 55 s,and the prediction time is only 2 s,which can effectively identify the attack intention of ICMP.

关键词： Internet control message protocol support vector machine covert tunnel network analysis

An End-To-End Hyperbolic Deep Graph Convolutional Neural Network Framework

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 537-563页

作者： yuchen zhou Hongtao Huo Zhiwen Hou Lingbin Bu Yifan Wang Jingyi Mao Xiaojun Lv Fanliang Bu School of Information Network Security People’s Public Security University of ChinaBeijing100038China Institute of Computing Technology China Academy of Railway Sciences Corporation LimitedBeijing100081China

Graph Convolutional Neural Networks(GCNs)have been widely used in various fields due to their powerful capabilities in processing graph-structured ***,GCNs encounter significant challenges when applied to scale-free graphs with power-law distributions,resulting in substantial ***,most of the existing GCN models are shallow structures,which restricts their ability to capture dependencies among distant nodes and more refined high-order node features in scale-free graphs with hierarchical *** more broadly and precisely apply GCNs to real-world graphs exhibiting scale-free or hierarchical structures and utilize multi-level aggregation of GCNs for capturing high-level information in local representations,we propose the Hyperbolic Deep Graph Convolutional Neural Network(HDGCNN),an end-to-end deep graph representation learning framework that can map scale-free graphs from Euclidean space to hyperbolic *** HDGCNN,we define the fundamental operations of deep graph convolutional neural networks in hyperbolic ***,we introduce a hyperbolic feature transformation method based on identity mapping and a dense connection scheme based on a novel non-local message passing *** addition,we present a neighborhood aggregation method that combines initial structural featureswith hyperbolic attention *** the above methods,HDGCNN effectively leverages both the structural features and node features of graph data,enabling enhanced exploration of non-local structural features and more refined node features in scale-free or hierarchical *** results demonstrate that HDGCNN achieves remarkable performance improvements over state-ofthe-art GCNs in node classification and link prediction tasks,even when utilizing low-dimensional embedding ***,when compared to shallow hyperbolic graph convolutional neural network models,HDGCNN exhibits notable advantages and performance enhanceme

关键词： Graph neural networks hyperbolic graph convolutional neural networks deep graph convolutional neural networks message passing framework

Surgical treatment of pulsatile tinnitus related to the sigmoid sinus

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Journal of Otology 2023年第1期18卷 21-25页

作者： Yuxuan Xing Song Gao yuchen zhou Shenghua Song Ling Lu Jie Chen Yanhong Dai Department of Otolaryngology Head and Neck Surgery Affiliated Drum Tower Hospital of Nanjing University Medical SchoolJiangsu Provincial Key Medical Discipline(Laboratory)Nanjing210008People's Republic of China Research Institute of Otolaryngology No.321 Zhongshan RoadNanjing210008People's Republic of China Department of Otolaryngology Head and Neck Surgery Drum Tower Hospital Clinical College of Nanjing Medical UniversityNanjing210008People's Republic of China

Objective: Tinnitus-a common clinical symptom-can be categorized into pulsatile tinnitus(PT) and non-PT. Among these, PT is usually associated with sigmoid sinus symptoms, such as sigmoid sinus wall defect or diverticulum, for which various surgical treatments are available. We have discussed the clinical efficacy of surgery for sigmoid sinus-associated PT via the transmastoid approach in this ***: We conducted a retrospective review of 4 patients who underwent surgery for sigmoid sinusassociated PT via the transmastoid approach at Nanjing Drum Tower Hospital from January to December2020. Of these, 2 patients had sigmoid sinus wall defect and 2 had sigmoid sinus diverticulum. Postoperative tinnitus grading and surgical efficacy were ***: After surgery, PT dissolved in 3 patients, while tinnitus significantly decreased in 1 *** the follow-up period of 12-18 months, none of the 4 patients showed complications related to increased intracranial pressure or venous sinus thrombosis, and tinnitus symptoms disappeared in 3patients without recurrence, although 1 patient occasionally developed tinnitus. Postoperative thin-slice CTA of the temporal bone indicated that the sigmoid sinus bone wall defect or diverticulum was completely repaired with a thick soft tissue ***: Surgical repair of sigmoid sinus-associated PT via the transmastoid approach deserves clinical promotion as it exhibited better efficiency while being relatively less invasive.

关键词： Pulsatile tinnitus Sigmoid sinus wall defect Sigmoid sinus diverticulum Efficacy of surgery Transmastoid approach

Finite Element Analysis of Elastic Deformation in Blade Machining

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International Journal of Plant Engineering and Management 2019年第1期24卷 10-18页

作者： ZHANG Hao LI Yu LUO Xiangyang zhou yuchen Zhejiang Ioformation Institute of Machinery Industry

In the process of milling the half-open impeller, the milling force ACTS on the half-open impeller will cause the machining deformation error of the half-open impeller. The impeller material studied in this paper is 7050-t7451 aluminum alloy, whose elastic modulus is 70.3 GPa, with low stiffness. Therefore, during milling, it is easy to cause elastic deformation of the cutter, thus causing machining errors and reducing machining surface quality. In addition, due to the low stiffness of blade surface, the deformation of blade surface is much larger than that of hub surface. Therefore, this paper only studies the deformation law of blade surface in the process of milling.

关键词： leaf blade elastic deformation finite element analysis milling