机器人三维路径规划问题的一种改进蚁群算法

本文研究移动机器人三维空间路径规划问题,针对三维空间的复杂地形特点,提出了一种基于改进蚁群算法的路径规划算法。文中首先描述了一种简单有效的环境建模方法,然后给出了算法在信息素呈现、路径点选取、信息素更新以及启发式函数设计等方面的改进方法。仿真结果证明了算法的可行性和可靠性。     

双参数Bézier曲线的升二次扩展

本文以二次Bernstein基函数为例,首次提出了含双参数基函数的新扩展——αβQ—Bern-stein基函数,此类基函数具有新的特点,即基函数的扩展次数一次性升高两次,且包含了二次多项式和带一个参数的三次多项式基函数的所有性质。基于这组基函数定义了αβQ—Bézier曲线,该曲线也含有参数,具有形状可调性,当α与β取某些值时曲线能达到C4连续或在某个端点处C0连续。最后与含两个参数的升一次Bézier曲线进行比较,该曲线具有调节范围广、灵活性更强的优势。     

基于JAVAEE的工作流引擎设计的探究

工作流系统作为办公自动化软件重要组成部分,其不仅能将企业相应数据有效的和网络连接起来,同时也能将之前单独的计算机个体组成一个有机的并能自动化运行的网络系统,以便为企业提供更多信息,为企业更好的服务。就目前来看,工作流系统不仅仅在办公自动化软件中应用,在其他生产销售领域也得到了广泛应用。但是这种工作流数据在一定程度上还处于运转过程中,而新的基于JAVAEE工作流引擎程序在目前不同企业使用中,其效果还是比较可观的。本文主要从工作流管理系统概念及构成、JAVAEE技术概况、基于JAVAEE工作流引擎的设计等方面,对基于JAVAEE的工作流引擎设计进行相应探讨。     

装饰设计专业《计算机辅助设计》辅助教学网站的建设研究

装饰艺术设计专业《计算机辅助设计》课程的教学,既要能学会熟练操作各类艺术设计软件,又要有装饰制图知识、艺术设计能力和独创性思维能力。而各类辅助设计软件彼此之间缺少必要的联系和连贯性,学生很难系统掌握。因此建设本课程的辅助教学网站很有必要,使传统课堂讲授和网络教学相结合。本文同时还从网站建设思路和建设方案等方面来探讨本课程的网站辅助教学方法。     

基于MSP430单片机的线路故障数据采集器硬件设计

基于MSP430的线路故障数据采集器整套设备具有超低功耗、高效管理故障指示器,对下与对上均采用无线通信方式且不会相互干扰等优势。文中以MSP430单片机为核心设计了一个专门用来管理挂接于配电线路的故障指示器的数据采集设备的硬件电路,并针对相关需求,给出了详细的硬件电路图。该系统可用于一次侧线路的故障检测,还可通过配合电能智能终端,应用于防窃电等场合。     

纯电动汽车太阳能辅助空调控制系统的硬件设计

纯电动汽车车载动力电池是其唯一的动力源且很有限,辅助设备消耗的电能减少了纯电动汽车的续驶里程,尤其是空调,所以开发高效的纯电动汽车空调系统是纯电动汽车能够被市场接受的关键。将纯电动汽车顶盖布满太阳电池,可以使空调系统的制冷能力增强,同时还能增加纯电动汽车的行驶距离。对小型纯电动汽车的太阳能辅助空调系统进行研究,设计出适合该空调的自动控制系统,可为纯电动汽车创造出一个更加舒适的驾驶和乘座环境。     

The need and prospects for improved fusion reactors

Conceptual fusion reactor studies over the past 10–15 yr have projected systems that may be too large, complex, and costly to be of commercial interest. One main direction for improved fusion reactors points toward smaller, higher-power-density approaches. First-order economic issues (i.e., unit direct cost and cost of electricity) are used to support the need for more compact fusion reactors. The results of a number of recent conceptual designs of reversed-field pinch, spheromak, and tokamak fusion reactors are summarized as examples of more compact approaches. While a focus has been placed on increasing the fusion-power-core mass power density beyond the minimum economic threshold of 100–200 kWe/tonne, other means by which the overall attractiveness of fusion as a long-term energy source are also addressed.Nomenclature a Plasma minor radius at outboard equatorial plane (m) - A Plasma aspect ratioR _T /a - AC Annual charges ($/yr) - b Plasma minor radius in vertical direction (m) - B Magentic field at plasma or blanket (T) - B _c Magnetic field at the coil (T) - B Toroidal magnetic field (T) - B Poloidal magnetic field (T) - BOP Balance of plant - C Coil - COE Cost of electricity (mills/kWeh) - CRFPR Compact RFP reactor - CT Compact torus (FRC or spheromak) - c _FPC Unit cost of fusion power core ($/kg) - DC Direct cost ($) - DZP Dense Z-pinch - E Escalation rate (1/yr) - EDC Escalation during construction ($) - ET Elongated tokamak - F Annual fuel charges ($/yr) - FC Component of UDC not strongly dependent or FPC size ($/kWe) - FW First wall - FPC Fusion power core - f _Aux Fraction of gross electric power recirculated to BOP - f ₁ (IC+IDC+EDC)/DC - f ₂ (O&M + SCR + F)/AC - IC Indirect cost ($) - IDC Interest during construction ($) - I _w Neutron first-wall loading (MW/m²) - i Toroidal plasma current (MA) - j Plasma current density, I/a² - k _B Boltzmann constant, 1.602(10)^–16 (J/keV) - LWR Light-water (fission) reactor - MPD Mass power density 1000P_E/M_FPC (kWe/tonne) - M _N Blanket energy multiplication of 14.1-MeV neutron energy - M _FPC Mass of fusion power core (tonne) - n Plasma density (m^–3) or toroidal MHD mode number - O&M Annual operating and maintenance cost ($/yr) - p _f Plant availability factor - PFD Poloidal field dominated (CTs, RFP, DZP) - P Construction time (yr) - P_TH Thermal power (MWt) - P _E Net electric power (1-)P _ET (MWe) - P_ET Total gross electric power (MWe) - p_f Fusion power (MW) - q Tokamak safety factor (B /B _gq )(a/R _T ) - q _e EngineeringQ value, 1/e - R _T Major toroidal radius (m) - RFP Reversed-field pinch - RPE Reactor plant equipment (Account 22) - S Shield - SCR Annual spare component cost ($/yr) - SSR Second stability region for the tokamak - S/T/H Stellarator/torsatron/heliotron - ST Spherical tokamak or spherical torus - T Plasma temperature (keV) - TDC Total direct cost ($) - TOC Total overnight cost ($) - UDC Unit direct cost,TDC/10 ³ P _E ($/kWe) - V _p Plasma volume (m³) - W _p Plasma energy (GJ) - W _B Magnetic field energy (GJ) - Magnetic utilization efficiency, 2nk_BT/(B ²/2₀) - ₀ Permeability of free space, 4(10)^–7 H/m - XE Plasma confinement efficiency, a²/4_E - _e Plasma energy confinement time - _p Overall plant efficiency, _TH(1-) - _TH Thermal conversion efficiency - _FPC AverageFPC mass density (tonne/m³) - Plasma vertical elongation factor,b/a - Thickness of allFPC engineering structure surround plasma (m) - Total recirculating power fraction, (P _ET-P _E)/P _ET, or inverse aspect ratioa/R _T This work was performed under the auspices of USDOE, Office of Fusion Energy.     

User-oriented product development applied to functional clothing design

A method for user-oriented product development is presented. After a theoretical introduction the method is applied to the development of functional clothing. The characteristic of the method is its starting-point with the user in the use-situation. Important product demands are derived from use-analyses. Three case-studies are described where this method has been applied. They concern working clothes, clothes for the elderly and military clothing. The quality of this methos as an instrument for product development in the clothing area is evaluated by comparing, on the one hand, this method with those usually used in the clothing industry, and on the other hand the new products with those formerly used. The method for user-oriented product development has proved to be complementary to conventional methods. It should be applied to products whose functional properties are of great importance. The method can be generalised to all users and to products with close connection to human beings.     

Aluminum. II. Derivation of C v0from C p and comparison to C v0 calculated from anharmonic models

The specific heat at constant pressure, C _p, of aluminum measured by Ditmars, Plint, and Shukla has been reduced to the volume V ₀ appropriate for 0 K employing the Murnaghan equation. The C _v0 thus obtained is compared with the theoretical C _v0 calculated in the harmonic and the lowest-order anharmonic approximation from three different pseudopotentials (Harrison, Ashcroft, and Dagens-Rasolt-Taylor) as well as a phenomenological Morse potential. The higher-order ( ⁴) anharmonic contributions are calculated from the same nearest-neighbor Morse potential as in the lowest-order anharmonic theory. The role of the vacancy and the higher-order anharmonic contributions to C _v0 has been examined and we conclude that the ⁴ contributions to C _v0 are much smaller than the vacancy contribution. After removal of the vacancy contribution, the reduced C _v0 is found to be in excellent agreement with the Ashcroft and Harrison pseudopotentials as well as the Morse potential including the ² and ⁴ contributions to C _v0.     

汽车同步器齿套摆线加工数控机床结构总体方案设计

将传统的汽车同步器齿套倒锥及滑块槽的几种加工方法，与用摆线逼近法加工汽车同步器齿套倒锥及滑块槽的加工方法加以比较，阐明了这种新方法产生的背景和优势；介绍了用摆线加工滑块槽的原理；在此基础上设计了汽车同步器齿套摆线加工数控机床的总体结构；给出了机床的主要动力和运动参数，最后展望了这种方法的应用前景。