In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of inform...In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of information technology.A matrix decoding method is proposed in this paper.The method is a universal data reconstruction scheme for erasure codes over binary fields.Besides a pre-judgment that whether errors can be recovered,the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors.Data reconstruction process of the new method has simple and clear steps,so it is beneficial for implementation of computer codes.And more,it can be applied to other non-binary fields easily,so it is expected that the method has an extensive application in the future.展开更多
Let Fq be a finite field. In this paper, a construction of Cartesian au-thentication codes from the normal form of a class of nilpotent matrices over the field Fq is presented. Moreover, assume that the encoding rules...Let Fq be a finite field. In this paper, a construction of Cartesian au-thentication codes from the normal form of a class of nilpotent matrices over the field Fq is presented. Moreover, assume that the encoding rules are chosen according to a uniform probability distribution, the probabilities PI and PS, of a successful im-personation attack and of a successful substitution attack respectively, of these codes are also computed.展开更多
Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC...Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC） scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation（CC） scheme and network-coded cooperation（NCC） scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability（SEP） performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio（SNR） values.展开更多
We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful atta...We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful attack of this code are also computed. For multi-sender authentication code,it allows a group of senders to construct an authenticated message for a receiver such that the receiver can verify authenticity of the received message.展开更多
神经辐射场(NeRF)在二维图像到三维场景重建领域展现出优异的性能,使用二维图像作为训练数据,能够重建出场景的三维结构,并能进行高质量的新视图渲染。尽管NeRF在三维场景重建领域是十分有效的,但也存在训练速度慢、推理时间长的问题,...神经辐射场(NeRF)在二维图像到三维场景重建领域展现出优异的性能,使用二维图像作为训练数据,能够重建出场景的三维结构,并能进行高质量的新视图渲染。尽管NeRF在三维场景重建领域是十分有效的,但也存在训练速度慢、推理时间长的问题,并且样本质量与三维场景重建质量密切关联。为解决NeRF在低样本质量情况下的高质量三维重建问题,本文使用2组不同哈希编码的NeRF来学习同一个场景,评估候选视图信息增益之间的差距来引导视图采样。提出一种基于RGB特征的下一个最优视图(next best view)导航技术新框架,该框架在稀疏训练数据上具有很强的鲁棒性,能够通过RGB特征评估捕获高信息增益的下一个最优视图,并优化NeRF训练,可以用最少的额外视图来提高新视图合成质量。通过对NeRF训练流程的优化,网络收敛速度提升大约10倍,显存占用降低39.8%,大量实验验证了该模型的有效性和鲁棒性。展开更多
随着强流脉冲功率装置的发展,强脉冲γ辐射的测量与诊断技术面临新的挑战。提出了一种散射编码成像系统,以精确测量强脉冲γ辐射剂量场的强度分布。引入薄散射靶以降低γ射线束强度,保护成像探测器免受剂量率损伤,同时避免对脉冲辐射场...随着强流脉冲功率装置的发展,强脉冲γ辐射的测量与诊断技术面临新的挑战。提出了一种散射编码成像系统,以精确测量强脉冲γ辐射剂量场的强度分布。引入薄散射靶以降低γ射线束强度,保护成像探测器免受剂量率损伤,同时避免对脉冲辐射场环境参数造成显著改变。采用环孔作为编码孔,并利用遗传算法结合MCNP(Monte Carlo N-Particle Transport Code)程序对环孔的内径、环宽和厚度进行优化。通过对比优化后的环孔、未采用最佳参数的环孔和针孔在多种源区结构下的重建图像,验证了优化后的环孔其空间分辨率优于未采用最佳参数的环孔和针孔,同时在系统未对准和源区强度不均的情况下仍能保持优异的成像质量。应用双边滤波技术进一步改善重建图像的对比度和均匀性。该系统为极端辐射环境下的辐射成像提供了一种新的实现途径。展开更多
模糊测试是目前比较流行的网络协议漏洞挖掘技术之一,但是存在现有网络协议模糊器对字段间的关联性探索不足的问题。为此,提出了一种基于字段信息和覆盖率反馈的模糊测试方法。该方法通过两个参数定量表示协议数据模型中不同字段的关系...模糊测试是目前比较流行的网络协议漏洞挖掘技术之一,但是存在现有网络协议模糊器对字段间的关联性探索不足的问题。为此,提出了一种基于字段信息和覆盖率反馈的模糊测试方法。该方法通过两个参数定量表示协议数据模型中不同字段的关系和每一个字段本身的影响力,并利用覆盖率信息持续学习更新,从而指导模糊测试向更高效的方向变异。基于该方法实现了基于字段信息和覆盖率反馈的模糊测试模糊器FMFuzzer(Field Message based Fuzzer),并与模糊器Boofuzz和PAVFuzz进行了对比实验。实验结果显示,在3种网络协议上,FMFuzzer的代码覆盖率模糊器Boofuzz和PAVFuzz分别平均提升了10.97%和6.63%,证明了本方法的有效性。展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61501064Sichuan Provincial Science and Technology Project under Grant No.2016GZ0122
文摘In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of information technology.A matrix decoding method is proposed in this paper.The method is a universal data reconstruction scheme for erasure codes over binary fields.Besides a pre-judgment that whether errors can be recovered,the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors.Data reconstruction process of the new method has simple and clear steps,so it is beneficial for implementation of computer codes.And more,it can be applied to other non-binary fields easily,so it is expected that the method has an extensive application in the future.
文摘Let Fq be a finite field. In this paper, a construction of Cartesian au-thentication codes from the normal form of a class of nilpotent matrices over the field Fq is presented. Moreover, assume that the encoding rules are chosen according to a uniform probability distribution, the probabilities PI and PS, of a successful im-personation attack and of a successful substitution attack respectively, of these codes are also computed.
基金supported by the National Natural Science Foundation of China(6104000561001126+5 种基金61271262)the China Postdoctoral Science Foundation Funded Project(201104916382012T50789)the Natural Science Foundation of Shannxi Province of China(2011JQ8036)the Special Fund for Basic Scientific Research of Central Colleges (CHD2012ZD005)the Research Fund of Zhejiang University of Technology(20100244)
文摘Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation（CFNCC） scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation（CC） scheme and network-coded cooperation（NCC） scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability（SEP） performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio（SNR） values.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61179026)the Fundamental Research of the Central Universities of China Civil Aviation University of Science Special(Grant No.3122016L005)
文摘We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful attack of this code are also computed. For multi-sender authentication code,it allows a group of senders to construct an authenticated message for a receiver such that the receiver can verify authenticity of the received message.
文摘神经辐射场(NeRF)在二维图像到三维场景重建领域展现出优异的性能,使用二维图像作为训练数据,能够重建出场景的三维结构,并能进行高质量的新视图渲染。尽管NeRF在三维场景重建领域是十分有效的,但也存在训练速度慢、推理时间长的问题,并且样本质量与三维场景重建质量密切关联。为解决NeRF在低样本质量情况下的高质量三维重建问题,本文使用2组不同哈希编码的NeRF来学习同一个场景,评估候选视图信息增益之间的差距来引导视图采样。提出一种基于RGB特征的下一个最优视图(next best view)导航技术新框架,该框架在稀疏训练数据上具有很强的鲁棒性,能够通过RGB特征评估捕获高信息增益的下一个最优视图,并优化NeRF训练,可以用最少的额外视图来提高新视图合成质量。通过对NeRF训练流程的优化,网络收敛速度提升大约10倍,显存占用降低39.8%,大量实验验证了该模型的有效性和鲁棒性。
文摘随着强流脉冲功率装置的发展,强脉冲γ辐射的测量与诊断技术面临新的挑战。提出了一种散射编码成像系统,以精确测量强脉冲γ辐射剂量场的强度分布。引入薄散射靶以降低γ射线束强度,保护成像探测器免受剂量率损伤,同时避免对脉冲辐射场环境参数造成显著改变。采用环孔作为编码孔,并利用遗传算法结合MCNP(Monte Carlo N-Particle Transport Code)程序对环孔的内径、环宽和厚度进行优化。通过对比优化后的环孔、未采用最佳参数的环孔和针孔在多种源区结构下的重建图像,验证了优化后的环孔其空间分辨率优于未采用最佳参数的环孔和针孔,同时在系统未对准和源区强度不均的情况下仍能保持优异的成像质量。应用双边滤波技术进一步改善重建图像的对比度和均匀性。该系统为极端辐射环境下的辐射成像提供了一种新的实现途径。
文摘模糊测试是目前比较流行的网络协议漏洞挖掘技术之一,但是存在现有网络协议模糊器对字段间的关联性探索不足的问题。为此,提出了一种基于字段信息和覆盖率反馈的模糊测试方法。该方法通过两个参数定量表示协议数据模型中不同字段的关系和每一个字段本身的影响力,并利用覆盖率信息持续学习更新,从而指导模糊测试向更高效的方向变异。基于该方法实现了基于字段信息和覆盖率反馈的模糊测试模糊器FMFuzzer(Field Message based Fuzzer),并与模糊器Boofuzz和PAVFuzz进行了对比实验。实验结果显示,在3种网络协议上,FMFuzzer的代码覆盖率模糊器Boofuzz和PAVFuzz分别平均提升了10.97%和6.63%,证明了本方法的有效性。
