二次虚代数整数环中的Euclid整环

唯一分解是整数环所具有的重要性质,当数系扩充到全体代数整数时,该性质将会消失。该文把整数环扩充到二次虚单纯代数整环,讨论了二次虚单纯代数整环的可既约分解性,进一步探讨了具有Euclid性质的整环,从而得到了二次虚单纯代数整环中能够实现唯一分解的一部分整环。

虚二次环的商环的单位群（英文）

本文研究了有理数域Q的二次扩域Q(d^(1/2))的整数环Rd的商环的单位群.利用二项式分解以及有限交换群的结构性质,获得了d=-3,-7,-11,-19,-43,-67,-163时Rd/?n的单位群结构,其中?是Rd的素元,n是任意正整数.所得的结果推广了由J.T.Cross(1983),G.H.Tang与H.D.Su(2010)对d=-1,以及Y.J.Wei(2016)对d=-2时关于Rd/?n的单位群的研究.

类数为1的虚二次整数环的商环的零因子图

对所有类数为1的虚二次整数环,以零因子图为工具研究它们关于极大理想的幂的商环,计算了商环的零因子图的直径,并给出了该图是否为平面图的判定条件.

虚二次环的商环的立方映射图的半正则性（英文）

令Q为有理数域,d=-3,-7,-11,-19,-43,-67,-163,K=Q(d^(1/2)).该文研究了K的整数环的商环的立方映射图的半正则性.

新型的环状层次应用层多播模型

提出了一种新型的环状层次应用层多播模型HVRB(Hierarchy Virtual Ring-based),它适合于拥有大规模多播成员的多播组。该模型以环作为拓扑结构,同时引入了虚环[1]的概念。采用了基于动态优先级的层次划分方法使得该环状拓扑结构随时间的变化性能逐步得到提高,并且采取一定的措施使得当出现数据传输错误时可以进行快速的恢复。由仿真试验结果可知该模型具有较高的数据传输率、较高的带宽利用率和较低的控制开销。应用该多播模型可以较好地提高多播的性能。

水下高压气体弹射柱体出筒时尾随气泡的数值模拟

从流体动力学角度研究了文题．整个系统分为气泡流场和外部水流场．气泡流场采用零维模型，且假定内部气体作绝热膨胀运动．水流场模型中，假定流体不可压缩、无粘、无旋，忽略液气界面的表面张力，采用在湿表面和气泡表面布置面源的边界无法求解．气泡表面满足运动学边界条件和动力学边界条件，湿表面满足运动学边界条件，据此求解源强的分布．处理了气泡与裙体相碰问题，在气泡与筒体交接处引入虚环，避免了此处强烈的奇性．计算结果显示，裙体所受压力在很短时间内达到最大值，之后迅速下降到负值．

Clinical and experimental study on gastric mucosal Pathology DNA cAMP and trace elements of pixu patients

AIMS The paper studies the relationship between spleen deficiency substance,spleen deficiency and gastric cancer. METHODS We adopted the IBAS 2000 image analysis system,501B SEM with 9100/60 energy chromatic dispersing X-ray analysis instrument technique,histologic chemistry and radio-immunity means to assay the ultramicro structure,in- testinal rnetaplasia subtypes,cAMP,DNA,trace element series and their oxides of the patients' gastric mucosa. RESULTS The incidence rates of gastric cancer,incom- plete colonic intestinal metaplasia and“background lesion”of spleen deficiency with Qi stagnation patients are remarkably higher than those of spleen Qi deficiency patients(P<0.05- 0.001 ).The levels of gastric mucosa cAMP,Zn,Cu,ZnO and CuO decreased from complete to incomplete intestinal meta- plasia and from small to colonic intestinal metaplasia,while DNA increased in the above sequence(P<0.05-0.001 ).The lev- els of DNA,cAMP,Zn,Cu,ZnO and CuO in gastric mucosa of incomplete colonic intestinal metaplasia tissue are not remark- ably different from those in gastric cancer tissue. CONCLUSION Gastric diseases of spleen dificiency with Qi stagnation has the tendency of cancerization; There is a close relationship between the incidence of incomplete colonic intestinal metaplasia and gastric cancer.

热水采暖系统的仿真水力计算

本文中提出将树枝管网视为虚环,建立了虚环方程,证明了环形管网的基尔霍夫定律是虚环方程的一种特殊形式,环形管网方程和虚环方程互相兼容,可联立求解。水温差产生的压力差作为一项能量,可加到虚环方程中,计算竖管的垂直水力失调工况。对于虚环和环网方程组,可用Excel填表求解得到仿真的水力工况,计算简便,本文通过实例验证了计算的正确性,结果表明计算误差小于1伊10-4Pa。

Radial Based Probabilistic Roadmap Motion Planning Method in Sparse Environment

A new dynamic path planning method in high dimensional workspace, radial based probabilistic roadmap motion (RBPRM) planning method, is presented. Different from general probabilistic roadmap motion planning methods, it uses straight lines as long as possible to construct a path graph, so the final path obtained from the graph is relatively shorter and straighter. Experimental results show the efficiency of the algorithm in finding shorter paths in sparse environment.

A hybrid DVE architecture based on temp server

A hybrid distributed virtual environment （DVE） architecture is presented by importing a peer-to-peer （P2P） idea into the traditional client/server （C/S） architecture to improve the DVE system＇s scalability. The mathematical model of the overload of the center server was built and a series of simulation experiments were performed to validate the conclusions. When the client number increases to a certain value, the hybrid architecture can reduce server overload with some special clients （temp servers） selected with a certain heuristic strategy. With this architecture, the DVE system can support more system clients with the same server hardware than the C/S architecture can. The server overload ＂pulse＂ phenomena causing by the exiting of the temp server can be resolved by adopting a more optimized temp server selecting strategy and by reducing the child client capability of the temp server. By combining the advantages of the C/S architecture and the P2P architecture, the hybrid DVE architecture can effectively improve the scalability of the DVE system. This is validated by theoretical analysis and simulation experiments.

Grid architecture model of network centric warfare

NCW(network centric warfare) is an information warfare concentrating on network. A global network-centric warfare architecture with OGSA grid technology is put forward,which is a four levels system including the user level, the application level, the grid middleware layer and the resource level. In grid middleware layer,based on virtual hosting environment, a BEPL4WS grid service composition method is introduced. In addition, the NCW grid service model is built with the help of Eclipse-SDK-3.0.1 and Bpws4j.

Architecture of HLA Based Distributed Virtual Geographic Environment

Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard.

Linking a Game Engine Environment to Architectural Information on the Semantic Web

Because of the importance of graphics and information within the domain of architecture, engineering and construction （AEC）, an appropriate combination of visualization technology and information management technology is of utter importance in the development of appropriately supporting design and construction applications. Virtual environments, however, tend not to make this information available. The sparse number of applications that present additional information furthermore tend to limit their scope to pure construction information and do not incorporate information from loosely related knowledge domains, such as cultural heritage or architectural history information. We therefore started an investigation of two of the newest developments in these domains, namely game engine technology and semantic web technology. This paper documents part of this research, containing a review and comparison of the most prominent game engines and documenting our architectural semantic web. A short test-case illustrates how both can be combined to enhance information visualization for architectural design and construction.

Modular Fixture Assembly Model for Virtual Assembly Design

To support modular fixture assembly design in virtual environment,a multi-view based modular fixture virtual assembly model is proposed.Instead of squeezing all assembly related information into a single model,three complementary views of assembly model,element information,function and structure,and assembly relationship are proposed to be used.The first view contains the detailed element information,while the other two explicitly capture the hierarchical function relationships and mating relationships respectively.These views are complementary in the sense that each view only contains a specific aspect of assembly related information while together they include required assembly related information.The proposed assembly model is specialized to accommodate the features of modular fixture virtual assembly design and applied in our developed prototype system.

Visual fatigue relief zone in an extra-long tunnel using virtual reality with wearable EEG-based devices

Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel. Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel. However, the setting form of visual fatigue relief zone, such as its length and location, is difficult to be designed and quantified. By integrating virtual reality(VR) apparatus with wearable electroencephalogram(EEG)-based devices, a hybrid method was proposed in this study to assist analyzers to formulate the layout of visual fatigue relief zone in the extra-long tunnel.The virtual environment of this study was based on an 11.5 km extra-long tunnel located in Yunnan Province in China.The results indicated that the use of natural landscape decoration inside the tunnel could improve driving fatigue with the growth rate of attention of the driver increased by more than 20%. The accumulation of driving fatigue had a negative effect on the fatigue relief. The results demonstrated that the optimal location of the fatigue relief zone was at the place where driving fatigue had just occurred rather than at the place where a certain amount of driving fatigue had accumulated.

＂Smart Cafe＂： A Mobile Local Computing System Based On Indoor Virtual Cloud

With network developing and virtualization rising, more and more indoor environment （POIs） such as care, library, office, even bus and subway can provide plenty of bandwidth and computing resources. Meanwhile many people daily spending much time in them are still suffering from the mobile device with limited resources. This situation implies a novel local cloud computing paradigm in which mobile device can leverage nearby resources to facilitate task execution. In this paper, we implement a mobile local computing system based on indoor virtual cloud. This system mainly contains three key components： 1）As to application, we create a parser to generate the ＂method call and cost tree＂ and analyze it to identify resource- intensive methods. 2） As to mobile device, we design a self-learning execution controller to make offtoading decision at runtime. 3） As to cloud, we construct a social scheduling based application-isolation virtual cloud model. The evaluation results demonstrate that our system is effective and efficient by evaluating CPU- intensive calculation application, Memory- intensive image translation application and I/ O-intensive image downloading application.

Agent-oriented Virtual Environment Modeling

Virtual environment has been widely applied in scientific research and considered as an important tool of exploring science. But constructing a real virtual environment is rather difficult. The difficulty cannot be compared with developing general software. It has a high demand for software technology. Obviously traditional methods are not competent for the job. Fortunately with the development of agent-oriented technologies, all problems seem to be solved. By classifying a virtual environment into four layers corresponding with real world and considering it as a collection of agents, the virtual objects can be mapped into agents and an agent model can be designed. Based on the idea that the state change of a system is caused by that of individuals and the mutual effect among them, a theory of agent behavior driven by event and belief is put forward. Such agent-oriented modeling method can cope with the demand for handling multi-dimension information. It is an effective technique for constructing a large and complex virtual environment.

Using relief texture for interactive and tangible virtual environments

This paper first introduces a way to improve interactivity with high polygon count virtual objects through the "mixed" use of image-based representation within one object. That is, both 3D polygonal and image-based representations are maintained for an object, and switched for rendering depending on the functional requirement of the object. Furthermore, in order to reduce the popping effect and provide smooth and gradual transition during the object representation switch, the object is subdivided with the subdivided parts possibly represented differently, i.e., using 3D models or images. As for the image-based representation, the relief texture (RT) method is used. In particular, through the use of the mixed representation, a new way called TangibleScreen is pro-posed to provide object tangibility by associating the image-based representation with a physical prop (projecting the RTs) in a selective and flexible way. Overall, the proposed method provides a way to maintain an interactive frame rate with selective perceptual details in a large-scale virtual environment, while allowing the user to interact with virtual objects in a tangible way.

Interactive sculpting of product shape based on constraint manipulation in virtual environment

In product concept design, not only designers with professional CAD skills, but also final customers take part in the design and evaluation of product shape styling. Because customers usually lack surface modelling background and are not familiar with concrete operations of commercial CAD systems, it is difficult for them to express their change intentions of product shape through professional CAD tools if they are not satisfied with the current shape design. This paper puts forward a method for creating, dragging and manipulating constraint and load represented in form of icon entity in interactive sculpting of product shape in virtual environment. The method supports customers manipulation of sculpting constraints or loads on sculpting shapes in virtual reality interaction to control the deformation of product shape. Constraints management based on icon entity is similar to spline lofting operation that is familiar to engineers, so users do not need to know surface details or have any professional knowledge of surface modelling, by only using their physical and engineering experience, they can manipulate the sculpting of product shape intuitively.

Generation of 3D Virtual Geographic Environment Based on Laser Scanning Technique

This paper demonstrates an experiment on the generation of 3D virtual geographic environment on the basis of experimental flight laser scanning data by a set of algorithms and methods that were developed to automatically interpret range images for extracting geo-spatial features and then to reconstruct geo-objects. The algorithms and methods for the interpretation and modeling of laser scanner data include triangulated-irregular-network (TIN)-based range image interpolation; mathematical-morphology (MM)-based range image filtering, feature extraction and range image segmentation, feature generalization and optimization, 3D objects reconstruction and modeling; computer-graphics (CG)-based visualization and animation of geographic virtual reality environment.