智能小车运动控制研究

智能小车运动控制系统由核心控制模块、小车平台、供电模块、速度检测模块、循迹防跌模块、红外防撞车模块等部分组成.其中核心控制模块,采用SST89E516RD2单片机,实现总体控制和逻辑处理等功能;小车平台采用半成品的小车平台,包括底盘、轮子、减速电机等部分,提供了智能小车的基本平台;速度检测模块和循迹防跌模块采用红外收发对管,可实现小车轮速的检测、检测道路标志和保证小车不能跌出平台边界;红外防撞车模块采用红外接近开关,输出高低电平信号,指示前方是否有小车;供电模块采用3节3.6V锂电池,后接采用芯片MC34063的降压电路,为小车提供稳定电源;人机接口模块由若干指示灯组成,可实现小车运行状态的显示、报警提示等功能.     

无线通信网络的多智能小车编队控制系统

首先设计了基于ARM Cortex-M3的智能小车控制系统,利用模块化理念设计了无线通信、磁场检测传感器、电机驱动等硬件模块,采用ZigBee设计了多智能小车协作控制的车载自组织无线通信网络,利用磁场检测完成小车的导航方式,采用旋转编码器实现小车的测速功能.然后在智能小车上移植了嵌入式μC/OS-Ⅱ实时操作系统,根据多智能小车协作控制要求,设计了智能小车分布式自主决策程序,实现多智能小车自由运行、队列跟随和路口协作等运行模式.最后采用线性最优二次型的车队跟随控制算法,实现多智能小车编队的启停、匀速和加减速控制,利用通信协商的路口协作算法,实现多智能小车路口协作任务.实验结果表明,设计的无线通信网络的多智能小车系统能够满足多智能小车协作控制、编队控制和路口协作控制要求.     

基于机器视觉的智能小车自动循迹及避障系统

本文使用STM32单片机作为核心控制器,并协同机器视觉模块OpenMV组成智能小车系统,针对摄像头提取的道路图像信息,采用阈值法和鲁棒线形回归算法提取道路引导线,采用多重模版匹配法提取障碍物信息,并结合传统PID控制技术和模糊控制技术,实现了智能小车系统的引导线自动循迹和避障功能.实验表明,在直径为4mm引导线场地中,小车巡线性能表现良好;在静态障碍物环境下,小车能够有效识别障碍物,并完成避障路径规划.     

智能循迹小车设计

采用飞思卡尔16位微控制器MC9S12DG128B作为核心控制单元。详细地介绍了智能循迹小车控制系统的硬件设计和软件设计与实现,本循迹小车采用两排激光传感器来进行道路信息的采集和霍尔传感器采集速度信息,通过相应运算后,软件判断其有效性,结合控制算法控制随动舵机给出合理舵值,控制前轮舵机转向,单片机再给出合适的PWM波占空比以控制电机转速,并用H桥驱动电机的正反转运行。该智能小车能够较好地完成循迹任务,并且能够从较快的速度完成规定的路径,始终保持稳定运行。     

基于MC9S12XS128单片机智能寻迹小车的设计

本文给出了智能小车寻迹系统的软硬件方案设计和开发流程.采用飞思卡尔MC9S12XS128单片机作为智能小车控制芯片,设计了电源、电机驱动、激光传感器以及测速等模块,小车的速度、转向控制采用PID控制方法,测试结果表明,小车能够平稳实现寻迹功能.     

基于图像识别的自主寻迹智能小车设计

针对小车自主寻迹行驶的要求,提出了一种基于ARM平台的摄像头循迹小车系统。小车系统以ST公司生产的STM32F103ZET6为微控制器,通过安装在小车前的OV7725摄像头采集道路信息。然后对路径图像信息进行除噪、黑线提取和路径识别后获得路径信息。再根据不同的路径信息控制电机,进而调整小车速度和方向,最终实现小车沿设定路径行驶。摄像头采集的图像和小车速度能够实时显示在LCD和数码管上。实验证明,小车实现了自主循迹功能,具有良好的鲁棒性和实时性。     

基于安卓系统的定位智能小车设计

为实现小车的远程监控,使其在无人驾驶的状态下精确驶向设定的定位点,设计了一种基于安卓操作系统和单片机控制系统的可定位智能小车。系统使用安卓手机作为远程监控设备,采用Eclipse集成编译环境,利用百度地图服务,设计了操控小车的APP。实际测试表明:手机通过小车携带的GPS传感器识别定位点,采用自行设计的控制策略得到小车的控制量,并下发命令至单片机,对小车的位置和速度进行控制,实现了预期的目的。     

基于凌阳SPCE061A单片机智能小车的设计

小车硬件系统以凌阳公司16位SPCE061A单片机为控制核心,选用驱动模块L298N驱动直流电机,以红外蔽障传感器检测道路上的黑色转弯标志线来实现小车的自动转向不跑出跑道的功能.     

一种基于80C51单片机控制的寻迹小车设计

寻迹小车采用光电传感器来识别白色路面中央的黑色引导线,通过80C51单片机实现对转向舵机和驱动电机的PWM控制,使小车实现快速稳定地寻线行驶.分模块阐述了寻迹小车的原理、软硬件设计及制作过程.针对路径特点对寻迹小车的方向控制和速度控制提出了舵机分级转向、速度分段控制的解决方案.实验表明,寻迹小车能够较快速、平稳地完成对各种曲率引导线的寻线行驶任务.     

基于积分分离PID控制的自平衡小车设计

以STM32F103VET6作为控制核心芯片,采用带加速度计的陀螺仪MPU6050构成小车姿态检测装置,采用双路驱动器TB6612FNG驱动带数字编码器的直流电机搭建了自平衡小车系统。采用积分分离式PID算法实现了车身平衡的快速稳定控制。经实验证明积分分离式PID算法能够快速、稳定地控制小车系统达到平衡状态。     

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.     

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that