六维腕力传感器非线性正解耦方法设计

多维力传感器利用其多个转换单元完成测量加载于其结构上未知负载的作用效果,解耦是其设计的重要组成部分。针对传统静态线性解耦方法的不足,试图将传统线性解耦方程扩展为多项式结构,受其多元高次方式通解形式的启发,构造了一种多项式非线性静态正解耦方程,该方法无需传统线性解耦方法中的曲线拟合、逆解,不依赖以系统是线性为前提,且方程可以扩展成任意结构的多项式。实验结果表明:该方法能降低输出耦合误差。     

Trusted Integrated Circuits: The Problem and Challenges

Hardware security has become more and more important in current information security architecture. Recently collected reports have shown that there may have been considerable hardware attacks prepared for possible military usage from all over the world. Due to the intrinsic difference from software security, hardware security has some special features and challenges. In order to guarantee hardware security, academia has proposed the concept of trusted integrated circuits, which aims at a secure circulation of IC design, manufacture and chip using. This paper reviews the main problems of trusted integrated circuits, and concludes four key domains of the trusted IC, namely the trusted IC design, trusted manufacture, trusted IP protection, and trusted chip authentication. The main challenges in those domains are also analyzed based on the current known techniques. Finally, the main limitations of the current techniques and possible future trends are discussed.     

溴虫腈土壤和甘蓝微量残留量的气相色谱法测定

采用气相色谱法定量分析溴虫腈土壤和甘蓝微量残留量。样品经丙酮提取 ,液 液分配及氧化铝柱层析法净化后 ,以GC ECD测定 ,DB 170 1毛细管柱 ,氮气为载气 ,柱温 2 6 0℃ ,汽化室温度 2 5 0℃ ,检测器温度 2 80℃ ,外标法定量。该方法快速、准确 ,在 0 0 1～ 2 0 0mg/L范围内线性相关系数r2 =0 9999,平均回收率 90 0 %～ 10 3 6 7% ,变异系数 4 4 8%～ 5 89% ,最小检测量 2× 10 12 g ,最低检出浓度 3 3× 10 4mg/kg。     

典型案例教学在《Android 开发技术》课程中的应用

随着移动互联技术的迅猛发展,很多高等学校在软件工程和计算机科学与技术专业开设《Android开发技术》课程,培养学生从事移动互联终端软件开发的能力,但在该课程教学过程中存在教学内容枯燥乏味、学生学习缺乏积极性和教学效果差等问题。分析该课程知识点的特点,提出利用“典型案例”贯穿该课程的核心知识点,教学实践显示该教学方法适合该课程的教学。     

基于级联迭代傅里叶变换算法的光学安全技术

基于级联迭代傅里叶（CIFT）变换算法提出了一种新的光学图像的加密方法,该方法通过输入和4-F相关的傅里叶域的模糊设计和定位,从而实现光学加密以及真实性验证。与以往的方法有所不同,新算法采用改进的搜索策略：修改两个阶段的同步分布,同时扩大搜索空间。计算机模拟实验表明其快速的收敛算法能够更好地恢复图像的质量,密钥会被分配到不同的方面,用户只有在得到这些密钥的授权之后才能得到解密后的图像,这种密钥分配策略可以极大减少被入侵的风险。     

四元数与欧拉角刚体动力学数值积分算法及其比较

为推广四元数保辛积分在工程中的应用,对欧拉角表示的状态方程数值积分与四元数的保辛积分进行比较.重陀螺的数值仿真结果表明四元数保辛积分的数值结果明显优于欧拉角状态方程积分.与欧拉角状态方程积分相比,四元数保辛积分在刚体动力学的数值仿真中更具优势.     

基于祖冲之类方法的多体动力学方程保能量保约束积分

针对一类多体动力学问题导出的微分 代数方程,提出一种保能量、保约束的算法.该算法基于祖冲之类方法和欧拉中点保辛差分,利用祖冲之类方法保证在时间格点上精确满足约束方程,避免约束违约问题;并进一步证明该算法在时间格点上可以精确保能量.数值算例进一步验证该算法的可靠性.     

喷动床反应模型的研究进展

喷动床是一种可实现热量重复循环的高效反应器 .介绍了目前喷动床研究中出现的各种反应模型 ,从等温和非等温两个方面讨论了一维轴向、流管、半分割和流动反应耦合等各类模型的基本思想和理论及各自的特点 ,并提出了进一步发展的方向 .     

Determination and correlation solubility of 4-nitroimidazole in twelve pure solvents from 278.15 K to 323.15 K

In this paper, the solubility of 4-nitroimidazole in twelve pure solvents (toluene, benzene, 1,4-dioxane, acetonitrile, ethyl acetate, acetone, GBL, ethanol, methanol, n-butanol, DMF and NMP) were determined by using the laser monitoring system from 278.15 K to 323.15 K under 101.1 kPa, which are 0.00018-0.00070, 0.00021-0.00073, 0.00034-0.00092, 0.00038-0.00142, 0.00047-0.00120, 0.00126-0.00303, 0.00225-0.00517, 0.00310-0.00724, 0.00467-0.00982, 0.00453-0.01940, 0.01947-0.04652, and 0.04670-0.07452, respectively. At constant temperature, the mole fraction solubility of 4-nitroimidazole were increased as the following order: toluene < benzene < 1,4-dioxane < (ethyl acetate or acetonitrile) < acetone < GBL < ethanol < (methanol or nbutanol) < DMF < NMP, and the solubility of 4-nitroimidazole in (ethyl acetate, acetonitrile) and (methanol, n-butanol) had an intersection point at 297.55 K and 281.85 K, respectively. The solubility of 4-nitroimidazole could be increased with increasing temperature in twelve pure solvents. The ideal model, modified Apelblat equation, polynomial empirical equation, and λh equation were used to correlate the experimental values. The experimental solubility values were employed to calculate the standard dissolution enthalpy, standard dissolution entropy and Gibbs energy. The dissolution of 4-nitroimidazole could be an endothermic process in twelve pure solvents. The determination and fitting solubility of 4-nitroimidazole have important guiding significance for the purification and crystallization of its preparation process.