To deal with over-shooting and gouging in high speed machining, a novel approach for velocity smooth link is proposed. Considering discrete tool path, cubic spline curve fitting is used to find dangerous points, and a...To deal with over-shooting and gouging in high speed machining, a novel approach for velocity smooth link is proposed. Considering discrete tool path, cubic spline curve fitting is used to find dangerous points, and according to spatial geometric properties of tool path and the kinematics theory, maximum optimal velocities at dangerous points are obtained. Based on method of velocity control characteristics stored in control system, a fast algorithm for velocity smooth link is analyzed and formulated. On-line implementation results show that the proposed approach makes velocity changing more smoothly compared with traditional velocity control methods and improves productivity greatly.展开更多
In this paper, a double-buffer traffic shaper was investigated to adjust video frame rate inflow into the TCP sender-buffer of a multimedia application source across a slow-speed link. In order to guarantee QoS across...In this paper, a double-buffer traffic shaper was investigated to adjust video frame rate inflow into the TCP sender-buffer of a multimedia application source across a slow-speed link. In order to guarantee QoS across a slow-speed link (i.e. 1 MBPS), the double-buffer traffic shaper was developed. In this paper, the buffer size dynamics of double-buffer was investigated. The arrival and departure of frames were modeled as a stochastic process. The transition matrix for the process was generated and the stationary probability computed. A simulation program was written in Matlab 7.0 to monitor the buffer fullness of the second buffer when a 3600 seconds H.263 encoder trace data was used as test data. In the second buffer, it was discovered that over 90% of the play-time, the buffer occupancy was upper bounded at 300 frames per second and utilization maintained below 30%.展开更多
在对TigerSHARC芯片上自带的Link口通信协议进行研究的基础上,提出其在FPGA上实现的方法,并编写了代码在ALTERA公司的STRATIX II FPGA EP2S60F672I4进行了工程实现,测试结果表明:在FPGA上实现的Link口传输速度可达500MB/s,且能够与Tiger...在对TigerSHARC芯片上自带的Link口通信协议进行研究的基础上,提出其在FPGA上实现的方法,并编写了代码在ALTERA公司的STRATIX II FPGA EP2S60F672I4进行了工程实现,测试结果表明:在FPGA上实现的Link口传输速度可达500MB/s,且能够与Tiger-SHARC自带的Link口完全兼容,该Link口在FPGA上的实现为TigerSHARC与FPGA之间的互联提供了一种新的框架结构,具有一定的实用和推广价值。展开更多
图像感知系统与图像显示系统与人类视觉功能接近,容易被人们所接受。在车载ADAS/ADS中,图像感知系统与图像显示系统得到广泛的应用。高清数字摄像头和高清显示设备的应用,催生了新的高速链路传输技术,SerDes作为其中的佼佼者,被广泛采...图像感知系统与图像显示系统与人类视觉功能接近,容易被人们所接受。在车载ADAS/ADS中,图像感知系统与图像显示系统得到广泛的应用。高清数字摄像头和高清显示设备的应用,催生了新的高速链路传输技术,SerDes作为其中的佼佼者,被广泛采用。芯片厂商提供了各种评价SerDes高速链路的传输性能的方案,其中Link Margin测试具有速度快,可操作性强,测试结果准确,容易实现现场测试等特点。介绍了一种简单易操作,可平台测试,也可实车测试的SerDes Link Margin测试方案。展开更多
基金This project is supported by National Hi-tech Research and Development Program of China (863 Program, No. 2002AA421150)Specialized Re-search Fund for Doctor Program of Higher Education of China (No. 20030335091).
文摘To deal with over-shooting and gouging in high speed machining, a novel approach for velocity smooth link is proposed. Considering discrete tool path, cubic spline curve fitting is used to find dangerous points, and according to spatial geometric properties of tool path and the kinematics theory, maximum optimal velocities at dangerous points are obtained. Based on method of velocity control characteristics stored in control system, a fast algorithm for velocity smooth link is analyzed and formulated. On-line implementation results show that the proposed approach makes velocity changing more smoothly compared with traditional velocity control methods and improves productivity greatly.
文摘In this paper, a double-buffer traffic shaper was investigated to adjust video frame rate inflow into the TCP sender-buffer of a multimedia application source across a slow-speed link. In order to guarantee QoS across a slow-speed link (i.e. 1 MBPS), the double-buffer traffic shaper was developed. In this paper, the buffer size dynamics of double-buffer was investigated. The arrival and departure of frames were modeled as a stochastic process. The transition matrix for the process was generated and the stationary probability computed. A simulation program was written in Matlab 7.0 to monitor the buffer fullness of the second buffer when a 3600 seconds H.263 encoder trace data was used as test data. In the second buffer, it was discovered that over 90% of the play-time, the buffer occupancy was upper bounded at 300 frames per second and utilization maintained below 30%.
文摘在对TigerSHARC芯片上自带的Link口通信协议进行研究的基础上,提出其在FPGA上实现的方法,并编写了代码在ALTERA公司的STRATIX II FPGA EP2S60F672I4进行了工程实现,测试结果表明:在FPGA上实现的Link口传输速度可达500MB/s,且能够与Tiger-SHARC自带的Link口完全兼容,该Link口在FPGA上的实现为TigerSHARC与FPGA之间的互联提供了一种新的框架结构,具有一定的实用和推广价值。
文摘图像感知系统与图像显示系统与人类视觉功能接近,容易被人们所接受。在车载ADAS/ADS中,图像感知系统与图像显示系统得到广泛的应用。高清数字摄像头和高清显示设备的应用,催生了新的高速链路传输技术,SerDes作为其中的佼佼者,被广泛采用。芯片厂商提供了各种评价SerDes高速链路的传输性能的方案,其中Link Margin测试具有速度快,可操作性强,测试结果准确,容易实现现场测试等特点。介绍了一种简单易操作,可平台测试,也可实车测试的SerDes Link Margin测试方案。