基于虚拟现实技术的校园漫游系统

以设计山东理工大学漫游系统为例,讨论了场景中模型的构建和优化、多通道立体显示以及基于VRP-SDK和MFC虚拟漫游系统的实现方法,并探讨了虚拟校园漫游系统实现过程中的一些关键技术.     

基于WTK的西华师范大学虚拟校园漫游系统的研究

复杂场景的虚拟漫游是虚拟现实研究的一个重要方面．以设计西华师范大学校园漫游系统为例，重点阐述虚拟场景中三维模型的构建与优化、立体显示的实现和基于WTK和MFC的虚拟漫游的实现，并介绍了该系统的设计目标和、WTK技术．     

基于Quest 3D虚拟漫游的探索与实践

以小区别墅为3D虚拟漫游系统对象,利用3Ds Max与Quest 3D平台作为开发工具,构建完全沉浸式别墅漫游系统.就系统在集成开发阶段VR场景中相机的创建、灯光的设置、VR场景的三折幕布发布等技术进行研究,提出以小区别墅完全沉浸式案例的虚拟仿真漫游系统的完整方案,并加以实现,为推进完全沉浸式虚拟仿真漫游系统的应用提供了实例参考.     

面向对象的航海模拟器细节层次视景建模

视景建模是航海模拟器视景仿真研究的一个重点，复杂的三维航海场景建模和三维数据的管理是航海模拟器视景仿真中必须解决的问题，它是航海模拟器视景仿真成功与否的关键所在，为引提出了一种面向对象的航海模拟器三维视景模型的细节层次数据结构，讨论了基于这种数据结构的实时视景仿真系统的实现。     

基于虚拟现实技术的校园漫游系统的设计

以广西工学院为原型,设计和实现了虚拟校园漫游系统。结合VRML和Java SAI,实现虚拟场景的自动漫游和人机交互。为提高场景浏览速度,还应用了一些模型文件的优化处理方法。     

一种数字矿山快速漫游的层次建模方法

针对虚拟数字矿山中三维场景渲染速度问题,以提高漫游过程细节层次的建模速度为目标,通过对三维场景中各模型的相关性定义,提出了一种快速结构分层建模方法。首先利用漫游场景中规则模型的视点相关性组织细节层次,通过结构分层有效组织和管理矿山漫游三维场景,从而减少场景程序文件容量;其次利用视点相关性提出的动态权系数算法,计算矿山各结构分层动态显示系数;以简单、快速的方式构建动态变化下的场景模型,实现数字矿山各结构块不同细节层次显示的虚拟漫游。实验结果表明,该方法能够有效减小程序文件,实现数字矿山三维场景的快速漫游。     

基于3DS室内模型的虚拟漫游关键技术研究

虚拟室内漫游技术已成为房地产销售的重要手段,长期以来3DS室内效果图得到广泛应用,但基于3DS室内模型的虚拟室内漫游技术鲜有研究。以3DS MAX、VC++和OpenGL软件为平台,对基于3DS室内模型虚拟漫游的几个关键技术进行研究。室内场景建模完全在3DS MAX软件下实现,为实现场景管理对墙体、地面和顶模型进行规划处理,用多边形建模法实现;室内场景管理则基于Portal技术,设计视锥体裁剪算法,实现了实时性漫游;室内漫游采用包围球碰撞检测技术,实现了真实感漫游。     

一种用于地下矿可视化生产管控系统的全路径漫游网络设计

为了在地下矿山可视化生产管控系统中实现井巷内部快速漫游的功能,设计一种虚拟全路径漫游网络(Virtual full path roaming network,VFPRN),作为快速漫游时视点运动的路径。VFPRN以分段井巷中线网络为基础,引入虚拟结点和虚拟边,在交岔口处生成连接任意两条巷道的三维圆弧(直线)边,使得视点在交岔口处移动时具有平滑的转弯效果。同时,对依附于虚拟结点的边按顺时针排序,便于交互式选择前方路径。介绍VFPRN的特点及其组成元素,对传统的邻接多重表的数据结构进行改造,设计VFPRN的内存数据结构和数据库表结构,给出基于井巷实体网络复合数据模型建立VFPRN的算法步骤,并介绍VFPRN在井巷交互式快速漫游和自动漫游功能中的应用方式。结果表明,基于此网络实现的井巷漫游功能满足了大型地下矿山三维场景中井巷内部快速巡检的需求。     

基于虚拟现实技术的大型场景视景仿真

虚拟现实技术在视景仿真方面的发展潜力巨大,尤其是在大场景三维虚拟漫游方面的应用,模型的逼真程度、大场景漫游速度一直是人们研究的重点,但在大型场景视景仿真中,往往在满足一定场景真实感的情况下会造成观察者的动态不适感。本文以山西大学校园场景为研究对象,对三维复原和漫游的实现过程及关键技术开展研究,三维重现了山西大学文科楼、理科楼、图书馆、学生宿舍等主要建筑,实现了山西大学校园的虚拟漫游、立体展示等功能。在此基础上,探讨了在满足漫游真实感的同时对大型场景建筑物的建模方法以及优化技巧。     

基于面向对象思想的虚拟场景漫游研究

基于面向对象的基本思想,用3DSMAX作为建模工具,进行模型优化和渲染,以室内场景为虚拟漫游场景,采用行为交互模块实现了虚拟场景漫游系统和系统的人机交互。     

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.     

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.     

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.     

A computer generator for randomly layered structures

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

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-