汽车防抱制动系统控制理论研究

讨论了汽车防抱制动系统模糊控制器的设计问题，以进一步提高防抱制动系统的制动效果．文中以双参数逻辑门限控制方法为基础提出了新的模糊控制逻辑，设计了基于车轮角加速度的两级模糊防抱控制器；使用Matlab 6．0建立了模糊控制器的仿真模型，并进行了仿真分析．分析结果表明该控制器能有效地适应不同的路况，与传统的控制器相比有更好的鲁棒性和制动效果，具有一定的应用价值．     

高速列车制动系统控制策略的研究

本文对高速列车制动控制系统进行了阐述,提出了在列车制动系统中采用模糊控制策略的方案,并对该模糊控制器进行了系统仿真．得出模糊控制对提高列车制动系统的灵敏性和可靠性具有指导意义。     

基于遗传算法的模糊控制规则优化的研究

模糊控制规则的正确选择是模糊控制器设计的关键,它决定了模糊控制系统的动态、静态性能和控制效果．针对传统的获取控制规则方法的不足,提出了在一个待优化模糊控制器的基础上,采用改进的遗传算法优化其模糊控制规则,从而使经过优化所获得的控制规则更加合理．最后对优化后的模糊控制器进行仿真比较研究,并将其应用于温室,实现温室温度的模糊控制．结果表明模糊控制规则经过优化后的模糊控制器的控制品质有较大的改善和提高．     

ABS整车布置方式对制动性能的影响

为分析防抱死系统的不同控制方式对整车制动性能的影响，基于滑移率的智能权函数模糊防抱死控制思想建立防抱死系统数学模型．通过Matlab／Simulink模决，建立了采用不同ABS控制方式的整车系统模型．利用该模型针对特定的工况进行了整车制动性能的仿真，并给出了ABS的布置方式．结果表明：独立和高选控制的布置方式能够充分利用路面条件进行制动，但车辆的稳定性被破坏；而低选控制方式的制动效能不及上述两种布置方式，但能保证车辆有较好的制动稳定性．     

一种基于GA的模糊神经网络控制器设计及应用

结合模糊控制，神经网络，遗传算法三种方法的优点，提出了一种基于遗传算法的模糊神经网络控制器，并分析了其网络结构和离线学习的方法，遗传算法基于全局优化策略，避免了反向传播学习算法易陷入局部最优的缺陷，仿真实验和在汽车防抱死制动系统中的应用表明这种控制方案是有效的，可行的。     

基于遗传算法的多变量模糊控制器的设计方法

针对多变量模糊控制器提出了一种基于遗传算法的模糊控制规则设计方法．该方法可以同时确定并优化多变量模糊控制器的结构和推理规则,适合于对一大类复杂非线性对象的控制．数值仿真研究表明,文中提出的设计方法是可行的     

汽车巡航智能跟随控制与仿真

为提高汽车行驶的主动安全性及缓解司机驾驭汽车的疲劳感,提出了汽车巡航智能跟随控制方法.应用模糊控制理论,以前车和巡航车间理论安全距离与实际相对距离偏差及两车速度偏差作为控制变量,设计智能巡航模糊逻辑控制器,将油门开度或制动踏板行程作为控制器输出变量,实现汽车巡航的智能跟随控制.利用Matlab/Simulink针对智能跟随控制功能实施了仿真验证,结果表明:设计的智能巡航模糊控制器能够有效地跟随前方车辆行驶并始终保持两车间的安全距离,说明该控制器具备较强的鲁棒性.     

电磁旋转涡流制动器制动力矩控制

研究了电磁旋转涡流制动器制动力矩控制方法。利用磁路分析法得到了制动力矩的计算公式,以及制动力矩与励磁电流及列车速度的数学关系,从而确定制动力矩控制系统的总体方案,阐述系统工作原理,说明系统各主要组成模块,建立其仿真模型,并根据系统总体方案完成模块集成。介绍了PID(比例-积分-微分)控制、模糊控制、模糊自适应PI控制3种制动力矩控制算法,说明控制器设计步骤。完成仿真计算,并对结果进行对比分析。结果表明,相对于开环控制,3种控制算法都能有效地控制制动力矩。此外,无论是系统瞬态性能指标,还是稳态性能指标,都是模糊自适应PI控制表现最佳,模糊控制次之,PID控制相对最差。     

模糊控制在热电厂尖峰加热器温度控制中的应用

针对热电厂供热系统尖峰加热器温度控制的现状。提出了一种智能控制的方法——温度的模糊控制，采用遗传算法寻优隶属函数参数，利用自组织近邻聚类法处理输入输出数据对，结合数据产生模糊规则和语言规则的方法得到模糊规则．仿真结果表明，所设计的模糊控制器控制性能可达到预定的效果。     

基于无人机的大气污染物模糊控制溯源算法的仿真实现

针对无人机的大气污染物溯源问题,提出了一种基于无人机的大气污染物模糊控制溯源算法。该算法结合无人机与模糊控制的特点,根据无人机实际所处环境设计一个模糊控制器并确定模糊控制器的输入、输出变量,模仿人脑的思维构建了模糊控制规则库,从而实现了无人机对大气污染物的智能溯源。算法在MATLAB环境中进行了仿真实验,仿真结果表明了该算法的有效性和可行性,为解决大气污染物溯源问题提供了一种新的思路。     

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.     

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)

正~~     

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).     

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.     

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.