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981.
Yao SONG Limin XIAO Liang WANG Guangjun QIN Bing WEI Baicheng YAN Chenhao ZHANG 《Frontiers of Computer Science》2022,16(5):165105
Wide-area high-performance computing is widely used for large-scale parallel computing applications owing to its high computing and storage resources. However, the geographical distribution of computing and storage resources makes efficient task distribution and data placement more challenging. To achieve a higher system performance, this study proposes a two-level global collaborative scheduling strategy for wide-area high-performance computing environments. The collaborative scheduling strategy integrates lightweight solution selection, redundant data placement and task stealing mechanisms, optimizing task distribution and data placement to achieve efficient computing in wide-area environments. The experimental results indicate that compared with the state-of-the-art collaborative scheduling algorithm HPS+, the proposed scheduling strategy reduces the makespan by 23.24%, improves computing and storage resource utilization by 8.28% and 21.73% respectively, and achieves similar global data migration costs. 相似文献
982.
针对现有交通流预测模型未能充分利用交通流数据的时空特征以实现准确预测的问题,提出一种结合注意力机制的卷积门控循环单元预测模型(ACGRU)。该模型利用卷积神经网络(CNN)和门控循环单元(GRU)提取交通流的时空特征,然后使用注意力机制生成含有注意力概率分布的交通流特征表示,同时利用交通流的周相似性提取周期特征,将所有特征相互融合进行回归预测。在真实交通流数据集上的实验表明,提出的ACGRU模型具有更高的预测精度,预测误差相比其他预测模型平均降低了9%。 相似文献
983.
针对经典视觉背景提取算法(ViBe)在动态背景场景下检测精度不高,以及长时间存在鬼影的问题,提出一种改进的视觉背景提取算法.该方法在背景模型初始化阶段考虑到像素点之间的颜色相似性以及空间距离,选取像素点邻域内的同质像素点对背景模型进行初始化;根据场景动态程度自适应调整每个像素点的阈值以及背景模型更新的速率,改善了在动态背景场景下的检测精度;根据光流判断像素点是否存在运动来把真实前景目标和鬼影区分开来并及时对背景模型进行修正,从而尽快消除鬼影现象.使用changedection测试集进行测试,改进后的ViBe算法在能提取到较完整前景目标的同时,检测准确率相比原始ViBe算法也有所提高. 相似文献
984.
An intelligent dental robot (IDR) is reported for the purpose of artificial denture verification and test. Methods: The IDR is composed of power system, intelligent control and driving system, sensor system and supporting system. Five Maxon motors are adopted to provide the driving force for the IDR. Novel motor linear actuators are developed to mimic the movement of human’s masticatory muscles. Forward and inverse kinematics of the IDR are analyzed. Seven high-precision pressure sensors are utilized to detect the force on individual artificial tooth. Results: Motion and force experiments are conducted on the IDR. The maximum biting force provided by the IDR is 490?N. Hysteresis rate of the biting force loading and unloading is less than 3%. The largest displacement for the mandible movement test is found to be 60, 9 and 22?mm in the vertical, protrusive and lateral directions, respectively. Conclusion: IDR can complete simulated human masticatory movement and provide sufficient biting force. Significance: The IDR provides clinical guidance for the design and performance test of artificial denture. 相似文献
985.
In this paper we propose a penalized Crouzeix–Raviart element method for eigenvalue problems of second order elliptic operators. The key idea is to add a penalty term to tune the local approximation property and the global continuity property of discrete eigenfunctions. The feature of this method is that by adjusting the penalty parameter, some of the resulted discrete eigenvalues are upper bounds of exact ones, and the others are lower bounds, and consequently a large portion of them can be reliable and approximate eigenvalues with high accuracy. Furthermore, we design an algorithm to select a penalty parameter which meets the condition. Finally we provide numerical tests to demonstrate the performance of the proposed method. 相似文献
986.
With the development of the satellite spatial resolution, high-resolution and high-quality remote sensing images require high stability of the observation satellite platform. Therefore, real-time attitude information is essential to enhance the accuracy and the robustness of the attitude control system in observation satellites. Through the use of the parallax observation system, this paper designs a novel framework to estimate the on-orbit attitude, which includes a complete deconvolution process, a detailed camera motion model, and a support vector regression algorithm to detect the attitude and deal with the latency. The proposed framework is testified by realistically simulated data and remote sensing images from the JL-1 satellite. Simulation and experiment results demonstrate that the proposed framework can detect and predict the attitude in real-time while the error is lower than \(1.125\,\upmu \mathrm{rad}\). 相似文献
987.
988.
Jianxun Zhao Xiaojie Zhai Xing Tao Zhe Li Qingshuang Wang Wanqiang Liu Limin Wang 《材料科学技术学报》2018,34(6):995-998
Ti45Zr38Ni17 + xZrH2 (x = 5, 10, 15 and 20 wt%) composite materials are produced by ball milling for 20 min. The results of XRD measurement show that the composite materials contain icosahedral quasicrystal phase (I-phase), FCC phase with a Ti2Ni type crystal and C14 Laves phase. After adding ZrH2, the composite materials include not only the individual phases mentioned above, but also the ZrH phase. These composite materials are used as the negative electrode material of the nickel-metal hydride batteries. The electrochemical hydrogen storage characteristics of the material after adding ZrH is investigated. The Ti45Zr38Ni17 + xZrH2 (x = 5, 10, 15 and 20 wt%) composite material has reached the maximum discharge capacity (83.2 mA h/g) when x equals 10. This maximum discharge capacity is much higher than that of Ti45Zr38Ni17 alloy without ZrH. After adding ZrH2, the high-rate discharge ability and the cycling stability are enhanced simultaneously. The improvement of the electrochemical properties can be attributed to the synergistic effects of ZrH2, and the synergistic effects in the composite electrodes are probably attributed to the entry of most of hydrogen atoms from weakly bond strength of the Zr-H to the I-phase structure in electrochemical reaction. 相似文献
990.