基于手势识别的虚拟环境体感交互控制

结合体感交互与虚拟环境技术,提出了一种基于手势识别的虚拟环境体感交互方法,采用Kinect体感设备,实时获取用户的手势数据,通过改进的动态时间规整算法,对所定义的手势语义进行识别,并根据识别结果,发出实时控制指令,实现与虚拟环境的自然交互.在此基础上,实现了基于Kinect手势识别的虚拟矿井交互系统,对交互方法进行测试.实验测试结果表明,手势识别正确率平均高达95.1%,实时性较好,所定义的虚拟矿井手势语义符合人们正常操作习惯,能实现与虚拟环境更加自然的人机交互,可以实现与虚拟矿井自然交互控制.     

三维环境手势自然交互范式研究

随着非接触式交互设备的出现和三维界面的广泛应用,传统的二维交互方式已经不能满足三维应用系统的需求,亟待研究三维界面的自然交互问题。结合用户认知心理和三维界面的特点,提出三维界面交互通用模型GOMSS(Goals,Operators,Methods,Selection Rules and Scenes),并将该模型应用于体感设备的手势交互研究,设计了三维环境手势自然交互范式。通过虚拟装配等系统进行评估,表明该手势交互模式在提升系统易学性和交互沉浸感方面的有效性。     

面向手势交互的古建场景快速搭建方法

随着行业快速发展,虚拟现实应用对人机交互方式的要求越来越高,基于非接触手势控制的交互方式日益普及.针对虚拟环境下三维场景构建问题,提出一种面向Leap Motion体感交互设备的古建筑三维场景快速搭建方法.通过Leap Motion获取手部运动数据,实现物理空间与三维空间的实时映射,以及三维模型交互控制与编辑;提出一种基于概率图模型的古建筑构件推荐方法,通过构造贝叶斯网络,实现古建筑各构件之间的概率关系推理;推荐结果实时反馈用户,用户可通过手势选择相应部件,并在三维空间优化模型位置,最终实现古建筑场景的快速搭建.实验证明,相比二维交互方式,本文方法有效利用三维空间信息,并实现模型推荐,因此更加直观、便捷、高效.      

面向虚拟装配的层次化交互手势技术

针对目前虚拟装配系统存在的用户体验不足问题,文中将手势识别技术引入虚拟装配的人机交互中,提出了一种面向虚拟装配操作的层次化交互手势模型;根据装配任务和交互模式的特点,提出了二级手势分类策略:先对交互手势进行初步分类再利用情境感知技术判断手势的类型;然后利用运动感知技术对手势的交互语义进行识别;接着通过对用户作业空间的手功能区感知来实现不同交互模式的自然过渡,从而降低用户在交互过程中的认知负担;最后通过自主开发的虚拟装配原型系统对文中提出的交互手势技术进行验证.实验结果表明,文中的层次化交互手势建模与识别方法能有效地增加虚拟装配环境中的人机交互效率和用户体验.     

大屏幕人机互动中关键技术的分析研究

大屏幕人机互动多媒体技术的展示系统广泛地应用在各种场合,人机交互方案已经成为现在研究的热点.大屏幕人机交互技术主要体现在人机交互时交互人体的跟踪、交互手势的跟踪与识别和交互时涉及到的文字输入等问题.     

基于ICONDENSATION算法的人手跟踪与手势识别算法

为实现基于手势的智能人机交互,提出了一种基于视觉的人手跟踪与手势识别算法.该方法以ICONDENSATION算法为基础,融合颜色与深度信息进行重要采样,结合轮廓信息并通过ASM模型的能量函数进行观测,根据最大后验概率对几种预定义的手势进行识别.实验结果表明,该算法能够有效地实现复杂背景下的人手跟踪与手势识别,为进一步实现智能人机交互奠定了基础.     

基于多传感技术相融合的手势交互系统研究

针对传统基于计算机视觉技术进行手势识别过程中存在极易受环境光照及遮挡等影响导致识别准确率和效率不高的问题,本文提出了基于MEMS传感器信号和视觉信号相融合的手势交互方法。该方法通过分别获取和处理视觉信号和MEMS传感器信号,独立计算出手势特征,最终根据不同的应用场景动态调整各种手势特征在融合模型中的权值,使其相互补充,相互修正,最终实现了根据手势特征实现人机交互的系统。实验表明,该方法的准确性和效率都很高,能够达到人机交互实时性及准确性的要求。     

虚拟装配环境中的人机交互技术研究

为了解决虚拟装配系统中的人机交互问题,结合虚拟装配环境,给出了数据手套和三维跟踪器的驱动类,阐述了数据手套和三维跟踪器的原始数据获取方法和处理策略.提出了综合使用数据手套和三维跟踪器数据进行手势识别与命令映射的方法;采用非模态的动态透明菜单和对话框作为数据手套和跟踪器的补充方式进行人机交互;讨论了通过虚拟手操作零部件模型的虚拟装配过程.通过开发基于三通道投影的虚拟装配环境,对数据手套、三维跟踪器以及头盔显示器等应用进行了实例验证,验证结果表明上述方法有效可行.     

基于手势识别的大屏幕文字输入系统

目前基于手势交互的系统应用越来越多,但都是简单的利用手势操作鼠标进行交互,没有向系统进行文字输入的功能。利用盲人字母手势作为输入手势,采用微软的体感设备Kinect获取深度图像,对其进行手势分割,再利用SIFT提取特征,得到手势字母,利用拼音输入法,提供了一种向系统输入汉字的功能。     

移动终端交互设计中手势指令识别方法改进研究

传统的手势指令识别在缩放、旋转、平移等转换过程中,一直存在手势图片出现形变使识别不准确。提出一种新的移动终端交互设计中手势指令识别改进方法。将质心距离函数看作全局特征对二维空间下的手势运动轨迹特征提取,对其进行改进,获取三维空间下手势轨迹特征,増加移动终端交互设计中第三维的手势轨迹信息,得到手势轨迹特征向量。将手势轨迹特征向量作为输入,通过随机森林方法对手势指令识别分类器进行训练,利用训练完成的分类器实现移动终端交互设计中手势指令的识别。实验结果表明,所提方法不仅能够保证移动终端交互设计中手势指令识别的实时性,而且识别精度高,认证效果好。     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.