平面或曲面曲线长度测量仪的设计实现

以单片机为核心，采用光电传感技术，加之适当设计的机械传动装置，将曲线上的位移转换为脉冲；使用电池供电，设计制作了便携、滚轮式曲线测量仪，推动滚轮沿曲线运动，显示器显示测量的结果。该测量仪适用于服装设计、打板过程中对袖隆、领口等部位进行曲线长度的测量。经服装厂实际使用，完全能够满足使用要求，可以取代进口弯尺。同时，此测量仪也可以推广应用到其他领域各种曲线的长度测量。     

点乘运算中整数表示方法研究

在椭圆曲线密码算法中,整数的表示方法在很大程度上决定了点乘运算的效率。本文对目前已有的整数表示方法(如NAF、窗口法、整数拆分等方法)进行了系统的研究,比较了它们的优劣,指出了它们的本质,即用不同的表示方法来减少整数的表示式中非零元的个数,以减少点乘运算中点加运算的次数。     

基于平差理论的不规则曲线数字化数据处理方法

基于最小二乘原理,建立了GIS中不规则曲线数字化数据处理的严密平差模型,应用附有参数的条件平差方法,给出了不规则曲线数字化数据处理的最优解,讨论了按照该模型处理后数字化数据的精度评定的方法.通过严密平差处理,减弱了GIS不规则曲线数字化数据的误差影响,提高了数字化数据的精度,相对于模拟法理论上更加严密,方法更加简单,对研究GIS的数据质量控制具有实用参考价值.     

Multivariate Modeling of Age and Retest in Longitudinal Studies of Cognitive Abilities.

Longitudinal multivariate mixed models were used to examine the correlates of change between memory and processing speed and the contribution of age and retest to such change correlates. Various age- and occasion-mixed models were fitted to 2 longitudinal data sets of adult individuals (N > 1,200). For both data sets, the results indicated that the correlation between the age slopes of memory and processing speed decreased when retest effects were included in the model. If retest effects existed in the data but were not modeled, the correlation between the age slopes was positively biased. The authors suggest that although the changes in memory and processing speed may be correlated over time, age alone does not capture such a covariation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

四元数分形的生成与研究

为实现三维分形,应用四元数作为迭代变量生成四维Julia集。在介绍了如何实现三维显示以及迭代方法选择之后,详细说明了生成四元数分形的具体过程,并给出图形实例。因为改进了逃逸时间算法的判别标准,因此,目标集合是边界点集。最后通过观察与分析,总结了四元数Julia集的某些特征,比较了它与复平面Julia集异同点,说明了两者之间的联系。     

复合曲线上点的坐标计算与放样

在道路和建筑物建设等过程中常常设计一些曲线,为了满足不同用途的需要,曲线的形式也不相同,在一个工程项目中有的曲线是由几条不同半径或曲率的线段组成,这样给曲线上点的坐标计算和放样带来不便,特别是在城市建设过程中,施工场地的限制。本文根据工程实例介绍了某个体育场施工中复合曲线上钻孔坐标的计算及测设方法。该方法适合于场地狭小,使用全站仪或测距仪配合计算器进行放样的工程。     

Study of TiN/BN bilayers produced by pulsed arc plasma

Bilayers of TiN/BN were produced by using a PAPVD (Plasma Assisted Physical Vapor Deposition) pulsed vacuum arc system. The equipment is formed by a reactor composed by a vacuum chamber with two face-to-face electrodes and an RLC circuit to produce the arc discharge. To obtain the BN coating a target of h-BN was used placed on the cathode and a substrates of silicon placed on the anode. The work gas was nitrogen at a pressure of 4.4×10⁻¹ mbar and a voltage of 240 V. In order to improve the adherence of the BN film, an interlayer of TiN was grown. In this case the chamber was filled with N₂ to produce the TiN coating, with a pressure of 1.7 mbar and a voltage of 300 V. By means of XRD (X-ray diffraction), the existence of TiN was determined finding different crystalline orientation in FCC phase. An FTIR (Fourier Transform Infrared Spectroscopy) was employed to determine sp³/sp² bonding ratio in the BN film.By plotting I-V curves the electrical properties of the bilayer were studied, observing a semiconductor behavior and this result was compared to the silicon substrate without coating.     

自由曲面截面线无干涉刀轨生成方法的研究

截面线法是数控加工中重要的也是应用较为广泛的一种刀具轨迹的生成方法．以球形刀加工自由曲面为例，对截面线无干涉刀轨生成方法进行了研究与探讨．该方法实现了对刀具干涉的快速分析检测与处理，提高了数控加工和生产效率．此外，该方法不仅可以在数控加工中生成无干涉刀具轨迹，而且可以确定加工中的欠切区域，以便于后续加工．     

利用HyperChem获取反应过渡态的方法

利用HyperChem的动态数据交换DDE(Dynamic Data Exchange)功能，通过Excel中的Visual BasicA编程来控制HyperChem的运行，从而控制反应过程中的反应坐标和反应步长，计算得到反应系统沿反应坐标的能量变化曲线，从而可获取反应的过渡态和活化能△E。利用该计算方法搜寻了喹啉分子在S-Mo-Ni催化剂晶体表面催化加氢反应的过渡态，取得较好的效果。利用该方法可以确定复杂反应过渡态，从而为实验研究起理论指导作用。     

Covariant-Conics Decomposition of Quartics for 2D Shape Recognition and Alignment

This paper outlines a new geometric parameterization of 2D curves where parameterization is in terms of geometric invariants and parameters that determine intrinsic coordinate systems. This new approach handles two fundamental problems: single-computation alignment, and recognition of 2D shapes under Euclidean or affine transformations. The approach is model-based: every shape is first fitted by a quartic represented by a fourth degree 2D polynomial. Based on the decomposition of this equation into three covariant conics, we are able, in both the Euclidean and the affine cases, to define a unique intrinsic coordinate system for non-singular bounded quartics that incorporates usable alignment information contained in the polynomial representation, a complete set of geometric invariants, and thus an associated canonical form for a quartic. This representation permits shape recognition based on 11 Euclidean invariants, or 8 affine invariants. This is illustrated in experiments with real data sets.