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311.
面向宇航应用,基于可重构片上互连,本文提出了一种新型的多核处理器架构。该架构在锁步技术的基础上进行了改进,利用可重构片上互连使得锁步技术引入的冗余核可以分时复用,以充分发挥多核性能。基于该架构的处理器软件编程,需对任务进行关键等级划分,使得非关键任务可以线程级并行执行,关键任务锁步执行,满足宇航应用对高可靠和高性能的需求。本文给出了该架构基于第五代精简指令集(RISC-V)的一种实现,并进行验证。结果表明:该架构实现了多核处理器在多核锁步和多核并行两种状态之间切换,分别获得高可靠或高性能的特性。 相似文献
312.
采用相对论平均场理论(RMFT)下的GL85,GL92,TM1和TM2等核物质参数组,研究了这些参数组对中子星的粒子数密度分布、状态方程及质量-半径关系的影响.结果表明,在不同的参数组下,超子出现的密度、顺序和种类均不同;状态方程的软硬情况也较大不同;中子星的引力质量和相应的半径有明显不同.计算结果也表明,采用GL85,TM1和TM2等参数组得到的中子星质量和半径均在脉冲星的观测数据范围内,而采用GL92参数组得到的中子星质量小于中子星质量下限1.4M⊙(M⊙=1.99×1030kg为太阳质量). 相似文献
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314.
Lili Yan Jian Wang Xiaohua Hao Zhiguang Tang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Precise glacier information is important for assessing climate change in remote mountain areas. To obtain more accurate glacier mapping, rough set theory, which can deal with vague and uncertainty information, was introduced to obtain optimal knowledge rules for glacier mapping. Optical images, thermal infrared band data, texture information and morphometric parameters were combined to build a decision table used in our proposed rough set theory method. After discretizing the real value attributes, decision rules were calculated through the decision rule generation algorithm for glacier mapping. A decision classifier based on the generated rules classified the multispectral image into glacier and non-glacier areas. The result of maximum likelihood classification (MLC) was used to compare with the result of the classification based on the rough set theory. Confusion matrix and visual interpretation were used to evaluate the overall accuracy of the results of the two methods. The accuracies of the rough set method and maximum likelihood classification were compared, yielding overall accuracies of 94.15% and 93.88%, respectively. It showed the area difference based on rough set was smaller by comparing the glacier areas of the rough set method and MLC with visual interpreter, respectively. The high accuracy for glacier mapping and the small area difference for glacier based on rough set theory demonstrated that this method was effective and promising for glacier mapping. 相似文献
315.
The circumferentially averaged equation of the inlet flow radial equilibrium in axial compressor was deduced.It indicates that the blade inlet radial pressure gradient is closely related to the radial component of the circumferential fluctuation (CF) source item.Several simplified cascades with/without aerodynamic loading were numerically studied to investigate the effects of blade bowing on the inlet flow radial equilibrium.A data reduction program was conducted to obtain the CF source from three-dimensional (3D) simulation results.Flow parameters at the passage inlet were focused on and each term in the radial equilibrium equation was discussed quantitatively.Results indicate that the inviscid blade force is the inducement of the inlet CF due to geometrical asymmetry.Blade bowing induces variation of the inlet CF,thus changes the radial pressure gradient and leads to flow migration before leading edge (LE) in the cascades.Positive bowing drives the inlet flow to migrate from end walls to mid-span and negative bowing turns it to the reverse direction to build a new equilibrium.In addition,comparative studies indicate that the inlet Mach number and blade loading can efficiently impact the effectiveness of blade bowing on radial equilibrium in compressor design. 相似文献
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317.
炭纤维壳体封头设计的几个问题 总被引:1,自引:0,他引:1
讨论了炭纤维壳体封头低压破坏的原因及3种破坏模式,即靠近赤道附近部位的封头发生断裂,极孔部位在环向应力作用下断裂和封头沿接头肩部外缘被剪(弯)断;得到了3种破坏模式的强度校核公式.给出了防止封头破坏宜采取的有效措施,对开孔很大的后封头,宜采取补强措施;给出了补强层厚度和补强范围的确定方法. 相似文献
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本组系列论文 ( )~ ( )从数学和认识论的角度系统地研究了无穷观问题的历史发展和现状 ,确立了无穷观背景世界的三分法原则 ,指出了两种无穷观相互排斥的局限性 ,形成了统一两种无穷于同一框架中的基本观点 ,并建立了一个统一实无限与潜无限于同一框架中的公理集合论系统 APAS。 相似文献