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Journal of rare Earths 2012年第6期30卷 524-528页

作者：黄盼姜浩锡张敏华 Key Laboratory for Green Chemical Technology of Ministry of Education R&D Center for Petrochemical TechnologyTianjin University

CeO2-ZrO2-Al2O3 ternary oxides were successfully prepared by a green route of supercritical anti-solvent precipitation with supercritical CO2 as anti-solvent and methanol as solvent. The structures and oxygen storage capacities of these ternary oxides were characterized by Xrd, raman spectra and oxygen storage capacity measurements. It was found that Al3＋ and Zr4＋ inserted into CeO2 lattice, forming CeO2-ZrO2-Al2O3 solid solution. The concentration of aluminium isopropoxide in the solution affected the concentration of oxygen vacancy and the distortion of oxygen sublattice which were responsible for the oxygen storage capacity. The rapidest oxygen uptake/release rate and maximum total oxygen storage capacity （122.0 mmolO2/molCeO2） were obtained with the aluminitun isopropoxide concentration at 0.2 wt.% in the solution.

关键词： CeO2-ZrO2-Al2O3 solid solution supercritical anti-solvent precipitation oxygen storage capacity rare earths

Fast Secret Key Generation Based on dynamic Private Pilot from Static Wireless Channels

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China Communications 2018年第11期15卷 171-183页

作者： Yu Huang Liang Jin Hongquan Wei Zhou Zhong Shengjun Zhang National digital Switching System Engineering and Technological r&d center Zhengzhou 450002 China.

In static or quasi-static wireless channel environments, secret key generation(SKG) based on wireless channels is vulnerable to active attacks due to the openness and invariance of public pilot, especially man-inthe-middle(MITM) attacks, where attacker acts as a transparent relay to manipulate channel measurements and derive the generated keys. In order to fight against this attack, a dynamic private pilot is designed, where both private pilot and secret key are derived from the characteristics of wireless channels and private to third party. In static or quasi-static environments, we use singular value decomposition techniques to reconstitute the wireless channels to improve the randomness of the wireless channels. Private pilot can encrypt and authenticate the wireless channels, which can make channel state information intercepted by MITM attacker reduced to zero and the SKG rate close to that without attacks. results of analysis and simulation show the proposed SKG scheme can withdraw the MITM attacks.

关键词： dynamic private pilot MITMattacks secret key generation wireless chan-nels physical layer security

SecIngress:An API Gateway Framework to Secure Cloud Applications Based on N-Variant System

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China Communications 2021年第8期18卷 17-34页

作者： dacheng Zhou Hongchang Chen Guozhen Cheng Weizhen He Lingshu Li National digital Switching System Engineering and Technological r&d center ZhengzhouHenan 450002China

Based on the diversified technology and the cross-validation mechanism,the N-variant system provides a secure service architecture for cloud providers to protect the cloud applications from attacks by executing multiple variants of a single software in parallel and then checking their behaviors’***,it is complex to upgrade current Software as a Service(SaaS)applications to adapt N-variant system *** arise from the inability of tenants to adjust the application architecture in the cloud environment,and the difficulty for cloud service providers to implement N-variant systems using existing API *** paper proposes SecIngress,an API gateway framework,to overcome the challenge that it is hard in the cloud environment to upgrade the applications based on N-variants *** design a two-stage timeout processing method to lessen the service latency and an Analytic Hierarchy Process Voting under the Metadata mechanism(AHPVM)to enhance voting *** implement a prototype in a testbed environment and analyze the security and performance metrics before and after deploying the prototype to show the effectiveness of *** results reveal that SecIngress enhances the reliability of cloud applications with acceptable performance degradation.

关键词： N-variant system API gateway cloud security analytic hierarchy process

Artificial Noise Aided Polar Codes for Physical LayerSecurity

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China Communications 2017年第12期14卷 15-24页

作者： Huiqing Bai Liang Jin Ming Yi China National digital Switching System Engineering and Technological r&d center Zhengzhou 450002 China

The secrecy rates of the existing practical secrecy coding methods are relative low to satisfy the security requirement of 5 G *** propose an artificial noise(AN) aided polar coding algorithm to improve the secrecy ***,a secrecy coding model based on AN is presented,where the confidential bits of last transmission code block are adopted as AN to inject into the current *** this way,the AN can only be eliminated from the jammed codeword by the legitimate *** the AN is shorter than the codeword,we then develop a suboptimal jamming positions selecting algorithm with the goal of maximizing the bit error rate of the *** and simulation results demonstrate that the proposed algorithm outperforms the random selection method and the method without AN.

关键词： physical layer security polarcodes artificial noise jamming positions se-lection

decellularized sciatic nerve matrix as a biodegradable conduit for peripheral nerve regeneration

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Neural regeneration research 2018年第10期13卷 1796-1803页

作者： Jongbae Choi Jun Ho Kim Ji Wook Jang Hyun Jung Kim Sung Hoon Choi Sung Won Kwon r&d center Genewel Co.Ltd. department of Surgery CHA Bundang Medical CenterCHA University

The use of autologous nerve grafts remains the gold standard for treating nerve defects, but current nerve repair techniques are limited by donor tissue availability and morbidity associated with tissue loss. recently, the use of conduits in nerve injury repair, made possible by tissue engineering, has shown therapeutic potential. We manufactured a biodegradable, collagen-based nerve conduit containing decellularized sciatic nerve matrix and compared this with a silicone conduit for peripheral nerve regeneration using a rat model. The collagen-based conduit contains nerve growth factor, brain-derived neurotrophic factor, and laminin, as demonstrated by enzyme-linked immunosorbent assay. Scanning electron microscopy images showed that the collagen-based conduit had an outer wall to prevent scar tissue infiltration and a porous inner structure to allow axonal growth. rats that were implanted with the collagen-based conduit to bridge a sciatic nerve defect experienced significantly improved motor and sensory nerve functions and greatly enhanced nerve regeneration compared with rats in the sham control group and the silicone conduit group. Our results suggest that the biodegradable collagen-based nerve conduit is more effective for peripheral nerve regeneration than the silicone conduit.

关键词： nerve regeneration biodegradable decellularized collagen nerve conduit growth factor peripheral nerve injury regeneration silicone conduit rat model

A Game-Theoretic Approach to Elastic Control in Software-defined Networking

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China Communications 2016年第5期13卷 103-109页

作者： Hongchang Chen Guozhen Cheng Zhiming Wang National digital Switching System Engineering&Technological r&d center Zhengzhou 450002China

Elastic control could balance the distributed control plane in Software-defined Networking(SdN). dynamic switch migration has been proposed to achieve it. However, existing schemes mainly focus on how to execute migration operation, but not why. This paper designs a decision-making mechanism based on zero-sum game theory to reelect a new controller as the master for migrated switches. It first chooses a switch for migration in the heavy controller which invites its neighbors as the game players to compete for the master role of this switch in the game-playing field(GPF) which is an occasional and loose domain for game-playing. Second, based on the concept of GPF, we design a decentralized strategy to play the game and determine which player as the final master. We implement it by extending the Open Flow protocol. Finally, numerical results demonstrate that our distributed strategy can approach elastic control plane with better performance.

关键词： software-defined networking master election game theory OpenFlow

defending Against Link Failure in Virtual Network Embedding Using a Hybrid Scheme

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China Communications 2019年第1期16卷 129-138页

作者： Jianjian Ai Hongchang Chen Zehua Guo Guozhen Cheng National digital Switching System Engineering & Technological r&d center University of Minnesota Twin Cities

Nowadays network virtualization is utterly *** a result,how to protect the virtual networks from attacking on the link is increasingly *** schemes are mainly backup-based,which suffer from data loss and are helpless to such attacks like data *** offer high security level,in this paper,we first propose a multipath and decision-making(Md) scheme which applies multipath simultaneously delivery and decision-making for protecting the virtual *** different security requirement for virtual link,we devise a hybrid scheme to protect the virtual *** the critical links,Md scheme is *** the other links,we adopt the Shared Backup *** simulation results indicate the proposed scheme can significantly increase the security level of the critical link high in the loss of less acceptance ratio.

关键词： network virtualization virtual link security multipath and decision-making hybrid scheme

Cyberspace Endogenous Safety and Security

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Engineering 2022年第8期8卷 179-185页

作者： Jiangxing Wu National digital Switching System Engineering&Technological r&d center Zhengzhou 450002China

Uncertain security threats caused by vulnerabilities and backdoors are the most serious and difficult problem in *** paper analyzes the philosophical and technical causes of the existence of so-called"dark functions"such as system vulnerabilities and backdoors,and points out that endogenous security problems cannot be completely eliminated at the theoretical and engineering levels;rather,it is necessary to develop or utilize the endogenous security functions of the system architecture *** addition,this paper gives a definition for and lists the main technical characteristics of endogenous safety and security in cyberspace,introduces endogenous safety and security mechanisms and characteristics based on dynamic heterogeneous redundancy(dHr)architecture,and describes the theoretical implications of a coding channel based on dHr.

关键词： Cyberspace endogenous security problem Uncertain threat Cyberspace endogenous safety and security relative right axiom dynamic heterogeneous redundant architecture

Improving Centralized Path Calculation Based on Graph Compression

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China Communications 2018年第6期15卷 120-124页

作者： Zhenglian Li Lixin Ji ruiyang Huang Shuxin Liu National digital Switching System Engineering&Technological r&d center ZhengzhouChina

Shortest-path calculation on weighted graphs are an essential operation in computer networks. The performance of such algorithms has become a critical challenge in emerging software-defined networks(SdN),since SdN controllers need to centralizedly perform a shortest-path query for every flow,usually on large-scale network. Unfortunately,one of the challenges is that current algorithms will become incalculable as the network size increases. Therefore, inspired by the compression graph in the field of compute visualization,we propose an efficient shortest path algorithm by compressing the original big network graph into a small one, but the important graph properties used to calculate path is reserved. We implement a centralized version of our approach in SdN-enabled network,and the evaluations validate the improvement compared with the well-known algorithms.

关键词： graph representation path compression shortest path

Activation redistribution Based Hybrid Asymmetric Quantization Method of Neural Networks

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 981-1000页

作者： Lu Wei Zhong Ma Chaojie Yang r&d Innovation center Xi’an Microelectronics Technology InstituteXi’an710065China

The demand for adopting neural networks in resource-constrained embedded devices is continuously *** is one of the most promising solutions to reduce computational cost and memory storage on embedded *** order to reduce the complexity and overhead of deploying neural networks on Integeronly hardware,most current quantization methods use a symmetric quantization mapping strategy to quantize a floating-point neural network into an integer ***,although symmetric quantization has the advantage of easier implementation,it is sub-optimal for cases where the range could be skewed and not *** often comes at the cost of lower *** paper proposed an activation redistribution-based hybrid asymmetric quantizationmethod for neural *** proposedmethod takes data distribution into consideration and can resolve the contradiction between the quantization accuracy and the ease of implementation,balance the trade-off between clipping range and quantization resolution,and thus improve the accuracy of the quantized neural *** experimental results indicate that the accuracy of the proposed method is 2.02%and 5.52%higher than the traditional symmetric quantization method for classification and detection tasks,*** proposed method paves the way for computationally intensive neural network models to be deployed on devices with limited computing *** will be available on https://***/ycjcy/Hybrid-Asymmetric-Quantization.

关键词： Quantization neural network hybrid asymmetric accuracy