Lattice-based key exchange on small integer solution problem

In this paper, we propose a new hard problem, called bilateral inhomogeneous small integer solution （Bi-ISIS）, which can be seen as an extension of the small integer solution problem on lattices. The main idea is that, instead of choosing a rectangle matrix, we choose a square matrix with small rank to generate Bi-ISIS problem without affecting the hardness of the underlying SIS problem. Based on this new problem, we present two new hardness problems： computational Bi-ISIS and decisional problems. As a direct application of these problems, we construct a new lattice-based key exchange （KE） protocol, which is analogous to the classic Diffie- Hellman KE protocol. We prove the security of this protocol and show that it provides better security in case of worst-case hardness of lattice problems, relatively efficient implementations, and great simplicity.     

无线可充电传感器网络的能量补充策略研究

为均衡网络能耗,及时为可充电无线传感器网络中能量较低的节点补充能量,本文提出一种基于非均匀分簇的多跳能量补充算法。该算采用非均匀分簇的多跳路由协议,每次充电前基站根据本文提出的剩余时间与地理位置联合优先权算法,计算出各簇的优先值后规划最优充电路径。仿真实验结果表明,本算法与其他算法相比有较好的扩展性,能有效均衡网络能耗并及时为节点充电。     

基于谱聚类的不平衡数据欠采样方法研究

不平衡数据的分类问题在数据挖掘和机器学习领域中,一直是备受关注的问题.论文从数据预处理方面出发,提出一种基于谱聚类的欠采样方法,以此来降低数据的不平衡程度.先对多类样本进行谱聚类,根据每个聚类簇的密集程度,以及到少类样本的平均距离,来计算每个聚类簇的采样数目和选取怎样的多类样本,此欠采样方法可以有效去除多数类的冗余数据.实验结果证明,该算法可以有效提升少类样本的分类效果.     

一种基于IHS和NSST的多光谱图像融合方法

文中针对丛林环境背景下的迷彩人员检测效果差的问题,提出一种基于多光谱图像融合的迷彩人员检测方法.以可见光图像和特征波段图像为数据源,首先将可见光图像变换到相关性最小的IHS颜色空间,提取出亮度分量I;然后对于特征波段图像和亮度分量I进行多级NSST分解变换图像融合,其中特征波段之间采用局部能量取大值融合规则低频分量融合,与亮度分量之间采用自适应模糊逻辑原则进行低频分量融合.高频分量均使用模值取大的融合规则.最后进行NSST逆变换和IHS逆变换得到融合结果.经实验表明,与其他经典和主流多尺度变换图像融合算法相比,该方法具备较好的图像质量评价指标,并且在迷彩人员检测实验中,与可见光图像结果相比,具有较好的检测结果.     

Connecting parameters optimization on unsymmetrical twin-tower structure linked by sky-bridge

Based on a simplified 3-DOF model of twin-tower structure linked by a sky-bridge, the frequency response functions, the displacement power spectral density （PSD） functions, and the time-averaged total vibration energy were derived, by assuming the white noise as the earthquake excitation. The effects of connecting parameters, such as linking stiffness ratio and linking damping ratio, on the structural vibration responses were then studied, and the optimal connecting parameters were obtained to minimize the vibration energy of either the independent monomer tower or the integral structure. The influences of sky-bridge elevation position on the optimal connecting parameters were also discussed. Finally, the distribution characteristics of the top displacement PSD and the structural responses, excited by El Centro, Taft and artificial waves, were compared in both frequency and time domain. It is found that the connecting parameters at either end of connection interactively affect the responses of the towers. The optimal connecting parameters can greatly improve the damping connections on their seismic reduction effectiveness, but are unable to reduce the seismic responses of the towers to the best extent simultaneously. It is also indicated that the optimal connecting parameters derived from the simplified 3-DOF model are applicable for two multi-story structures linked by a sky-bridge with dampers. The seismic reduction effectiveness obtained varies from 0.3 to 1.0 with different sky-bridge mass ratio. The displacement responses of the example structures are reduced by approximately 22% with sky-bridge connections.     

卧式加工中心试验模态分析

应用变时基采样的锤击法对卧式加工中心进行了试验模态分析，研究了该加工中心的动态特性，获得了感兴趣低频段的加工中心低阶固有频率。通过对整机各阶模态振型的分析，找到了加工中心结构的薄弱环节，为进行结构的优化设计指出了改进的方向。     

焊接反变形在叠梁焊接过程中的应用

本文针对不对称H型叠梁焊接过程中出现的挠曲变形问题进行了理论研究,通过焊接试验及理论计算, 分析了影响焊接变形的主要因素,确定了不对称H型梁焊接挠曲变形的经验公式。采用焊前反变形有效解决了不对称 H型叠梁焊接挠曲变形的难题,优化了大型叠梁制作工艺,保证了焊接质量。     

从试金分析谈金银的再生

试金分析是指从含金的矿石中或铜、铅阳极泥中，以火法、酸溶为主分析其中含金量克／吨。其程序分为五步：1。采矿样、破碎、细磨、过筛、混合均匀、采用四分法取两份分别放在相同编号的黏土坩锅内，同时加些造渣熔剂一炭酸钠造渣和还原用的Pb2O3(黄色粉末状俗称密陀僧)混合后再插一根细铁棒，等待装炉。2．将装好的物料放在高温马弗炉内熔化，达到Pb2O3还原为金属铅，其他非金属化合物和金属氧化物均进入熔融的液态废渣中。由于分散的三氧化铅在还原过程与不易氧化的金银合金有“亲合力”，因此矿物中分散的金银、全部以分子状态熔解在液态铅中。此时从马弗炉中用铁钳取出坩锅，一方面用小铁钳夹住残剩的铁棒在液态熔液中来回搅动几次，     

均匀设计在全光亮化学镀镍研究中的应用

"均匀设计法"是建立在数论基础上的最新的试验设计技术,该方法可用最少的试验次数对受多因素影响的复杂体系进行优化以寻找最佳工艺参数.用"均匀设计法"对提高化学镀镍的光亮性进行了研究,试验结果用计算机进行处理,获得了光亮化学镀液的最佳组成,并用该化学镀液镀出了镜面全光亮的镍磷镀层.     

5t铝箔退火炉炉温均匀性的改进

从铝箔退火炉通风结构存在的问题着手，在分析、计算炉子通风能力的基础上改装了风机并使风道合理化，从而提高了退火炉炉温的均匀性，并满足了生产需要。