基于SD*lite的月球车任务规划算法

月球车任务规划是在给定初始位置和目标位置,满足月面地形约束、工作模式约束以及能量约束的前提下,规划出月球车最优的路径。设计了一种月球车任务规划的模型,提出了一种基于SD*lite算法的规划器,在原有SD*lite算法的基础上进一步考虑了对可用资源的限制;它可以协助月球车在考虑太阳能帆板的能量约束的条件下,合理避障最终达到目标点,使规划的轨迹更符合实际。     

Implementation of MAC-based RTL module for Inverse DCT in H.264/AVC

In this paper, we implemented the MAC-based RTL module for inverse DCT in H.264/AVC to improve applicability, to reduce processing time and utilize resources. The paper highlights design of FU architecture, its interconnection topology, regular formula of inverse DCT and array processor mapping as well as MAC-based RTL module constructing. Multi-directional FUA and FPGA were presented along with an evaluated performance and simulation result. Hence, the paper encompasses design of single FU that was verified with the performance test at maximum frequency 200 MHz; the designed 4-by-4 FUA operates over 100 MHz. The proposed multi-directional FU can be extended to n-by-n FUA that functionality can be extended to next video coding standard (H.265/HEVC).     

The α- to β-Si3N4 transformation in the presence of liquid silicon

The compacts consisted of , -Si₃N₄ and free silicon are heat treated in the range 1650° C to 1750° C in an argon atmosphere in order to observe the following behaviours; the to phase transformation and variations of the microstructure during heat treatment in silicon nitride. For the microstructural observation of the heat treated specimens, the same grains in the polished surface were investigated before and after eliminating the retained silicon by etching. The to phase transformation, in this case, occurs via silicon melts irrespective of added -Si₃N₄. Both and phases are soluted and precipitated into molten silicon and their morphology are changed from an equiaxed shape to prismatic one. Although elongated grains are precipitated at low temperature or in the early stage of heat treatment, fine precipitated grains are mainly observed with increasing heat treating temperature.     

基于机器视觉的隔热条尺寸测量系统

针对当前隔热条的尺寸测量仍停留在产品离线后,工作人员用卡尺测量,劳动强度大,工作效率低、测量精度易受人为因素影响的现状,本文提出将机器视觉技术引入到隔热条自动化生产线的在线尺寸检测系统中,这种非接触式测量既可以避免在测量过程中对隔热条的损坏,又可以提高测量精度和测量速度,从而达到提高测量效能的目的。     

带有弯曲静子的压气机数值仿真

针对某两级低速轴流压气机第一级静子通道小流量范围内存在轮毂-角区失速现象,为了提高压气机的效率,采用计算流体力学方法,对第一级静子进行了不同的弯曲变化数值仿真,分析研究了静子弯曲对压气机性能和轮毂-角区失速的影响。结果表明,弯曲叶片能够通过改变静子轮毂表面静压分布,减缓低能流体的横向流动,从而有效地抑制小流量范围内的轮毂-角区失速,压气机的压比和效率得到较大的提升。     

天然酯绝缘油改性的研究进展

天然酯绝缘油具有较高的燃点和闪点、优异的天然降解能力和良好的绝缘性能,是矿物绝缘油的绿色替代品.由于其自身的理化特性,将其应用于变电设备还面临着很多挑战.本文综述了天然酯绝缘油的制备工艺,结合天然酯绝缘油的不足之处,从添加剂改性、混合改性、纳米改性及化学改性等方面阐述了天然酯绝缘油的研究成果,并对未来的研究方向进行了展望.     

Selective oxidation of Fe-30Ni alloy in a low-temperature range (433–473 K)

Fe-30Ni alloy specimens were oxidized for 10–240 min at 433–473 K in pure oxygen at a pressure of 1.33×10⁴ Pa. The thickness of oxide films was measured by a multiple-angle-of-incidence ellipsometer. The kinetics of film growth were found to obey a parabolic rate law. The depth-profiling of oxidized surfaces, performed with simultaneous use of Auger electron spectroscopy (AES) and argon-ion sputter-etching technique, reveals that iron component is selectively oxidized and an iron-depeletion zone is formed in the underlying alloy. The thickness of the iron depletion zone increases with increasing oxidation time or oxidation temperature. During surface oxidation of the alloy, the transport rate of iron component in the film is almost equal to the interdiffusion rate in the underlying alloy, indicating the establishment of a steady state. The values of the interdiffusion coefficient, , of the underlying alloy estimated from the depth-composition profiles are more than 10 orders of magnitude as large as the values extrapolated from the lattice diffusion data of the corresponding alloy obtained at high temperature. The enormously large values of may be explained in terms of the vacancy (monovacancy or divacancy)-enhanced lattice diffusion mechanism.     

云关系模式及其应用*

在云变换的基础上,结合非经典关系数据库理论提出了云关系模式,给出了云关系模式的定义,探讨了云关系模式的意义,并将它应用于学生成绩数据库中,改进了目前学生定性评定方法,克服了其中的主观因素,实例证明该方法具有可行性.