因式分解的三维非刚体重建方法

为了实现三维非刚体的重建,提出了一种因式分解的三维非刚体重建方法,该方法首先利用图像点和深度因子构成的图像矩阵为低秩的特性,求到相差一个变换矩阵的射影重建;再利用投影矩阵的约束关系,线性地求解出该变换矩阵,完成到欧氏重建的过渡。该方法采用线性方法求变换矩阵,而且在求解过程中将所有图像平等地对待。模拟实验和真实实验数据结果表明,该重建方法具有鲁棒性好、重投影误差小等优点。     

3维子空间约束的遮挡点恢复方法

为了有效地恢复跟踪过程中丢失的特征点,假设相机为正投影模型,提出了一种遮挡点恢复方法,其主要是利用所有的图像序列构成的、由行向量生成的线性子空间之和与空间结构点构成的、由行向量生成的子空间是同一个线性子空间的特性,构造了一种线性迭代算法.该方法的优点是在求解遮挡点的位置时,利用了所有的图像点信息,而且将所有的图像及图像点平等地看待.模拟、真实实验表明,所提方法的重投影误差仅比原有图像的噪声约大15%,这说明算法具有较好的收敛性.     

一种准线性光束平差方法

为了解决光束平差运行速度慢、复杂度高的缺点,提出了一种准线性光束平差方法(QBA),该方法利用深度因子等于投影矩阵的第3行与射影空间点相乘的特性,采用重投影点和已知图像点的代数距离建立目标函数,交替地将投影矩阵和射影空间点两个量中的一个保持不变,线性地求取另一个量,最后完成射影重建.实验结果表明,QBA方法具有较快的收敛速度,同时和传统的Levenberg-Marquat方法及Mahamud方法比较,QBA方法运行时间约是L-M方法的1/8,是Ma-hamud方法的1/3.     

最小化重投影误差的PFR三维射影重建

基于PowerFactorization(PF)仿射重建算法提出了一种最小化重投影误差的线性射影重建算法PFR(PF reprojection).该算法通过线性算法实现了重投影误差的最小化.算法通过添加权值参数将重投影误差非线性的代价函数转化为三线性的代价函数,并基于摄像机运动、三维场景结构以及射影深度之间的加权交错最小二乘法实现了重投影误差的交错最小化.实验结果表明本算法能在不影响输出精度的前提下提升射影重建30%的整体效率,适合作为标准光束法平差算法的引导算法或与光束法平差组成混合算法.     

一种基于奇异值分解的分层重构算法

以仿射投影来逼近透视投影,采用共轭梯度法迭代估计射影深度,通过测量矩阵的奇异值分解实现射影重构.在摄象机内参数已知的情况下,求解一个满足欧氏重构条件的4×4非奇异矩阵,由此矩阵将射影重构变换为欧氏重构.实验结果表明该算法是行之有效的.     

一种基于标记点的近景摄影测量系统

给出了一种基于标记点的鲁棒三维重建摄影测量系统;采用编码点和非编码点等标记点方式.为了减少不同图像间误匹配的概率,采用一种新的基于编码点的匹配方法,不同图像间非编码点的匹配从编码点开始,并通过相似性准则、模糊度准则和距离误差准则来剔除误匹配,可获得非常高的正确匹配率.采用一种新的基于标记点的加权迭代特征算法,用编码点恢复相机的投影矩阵,从而可以确定相机的外部姿态参数;用非编码点恢复3D坐标.与已有的加权迭代特征算法比较,该算法避免了所有点参与计算相机的投影矩阵,运算速度更快.由于采用标记点的亚像素定位方法,提高了3D重建精度.实验结果表明,在3D重建方面,该系统是强壮和精确的.     

MIT中灵敏度矩阵的聚类优化

针对灵敏度矩阵的几何差异性问题,提出了一种基于聚类优化的灵敏度矩阵方法.首先,分析了灵敏度矩阵的几何差异性对MIT图像质量的影响;然后,基于几何差异性对灵敏度矩阵的向量进行聚类分组,应用能量函数对分组后的灵敏度向量赋予不同权值,构造一种聚类优化的灵敏度矩阵;最后,应用优化后的灵敏度矩阵,通过线性反投影算法和牛顿-拉夫逊迭代算法进行MIT图像重建.实验结果表明:采用聚类优化的灵敏度矩阵,使线性反投影算法的均方误差降低26%以上,图像相关系数提高10%以上, 使牛顿-拉夫逊迭代算法的均方误差降低5%以上,相关系数提高4%以上,证明了所提方法的有效性.     

基于L-M算法的射影重建技术研究

在研究已有射影重建算法的基础上，利用L-M算法对基于基础矩阵的射影重建算法得到的线性结果进行优化，提高了算法的估计精度和稳定性，并在求得所有图象对应的投影矩阵后利用Bundle adjustment方法对空间结构及投影矩阵进行全局优化，取得了良好的效果。     

一维子空间的三维重建方法

为了从图像序列中恢复三维物体,假设相机为正投影模型,提出了一种基于一维子空间的三维重建方法.利用所有图像序列构成的行向量生成的子空间之和与三维空间点构成的行向量生成的子空间是同一线性子空间、同时由所有图像点构成的2个行向量外加一个行向量就可以组成该子空间的一个基底的特性,线性地求取子空间中的行向量,最后完成三维重建.模拟和真实实验结果表明,该重建方法具有鲁棒性好、重投影误差小等优点,而且能够将图像平等地对待.     

一种新的非线性相机模型标定方法

提出一种新的非线性相机模型标定方法.该方法考虑各种成像误差,用二元函数的多项式建立成像误差模型,用一个中间变量代替非线性畸变因素.在已知至少6个不共面点的空间坐标及对应的图像坐标,利用线性算法求解出非线性畸变模型的投影矩阵,用修正后的投影矩阵进行三维重建.实验结果表明,整个修正过程避免非线性方程的求解,10个修正参数由线性方程组一并解出,修正模型三维重建的精度整体得到提高.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-