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121.
针对目前“保留所有权利”的版权声明方式导致网络作品无法得到最大价值的利用或最广泛传播的现状,介绍“CC”协议的
产生原因和发展,分析“CC”知识共享的理念,指出理论上虽然“CC”协议解决了传统著作权保护模式在网络时代所遇到的诸多问题,
但鉴于中国版权保护的现状,“CC”能否达到其本来目的尚需进一步商榷。 相似文献
122.
时隙ALOHA使用了各种控制算法以保证系统的稳定性,在应用控制算法前,必须对算法的性能进行前期仿真测试.在比较三种常用网络仿真工具的基础上,分析了MATLAB离散事件仿真原理及基于蒙特卡洛法的随机数生成原理.给出了MATLAB仿真平台下实现时隙ALoHA控制算法的流程图,并依据该流程编写了MATLAB代码对时隙ALOHA的伪贝叶控制算法性能进行测试.仿真结果表示,MATLAB能很好的实现对时隙ALOHA控制算法的仿真. 相似文献
123.
基于Spring Security的Web资源访问控制 总被引:2,自引:0,他引:2
Web应用的访问控制一直以来受到广泛关注。由于Http的无状态性,给应用的安全设计带来较大难度。Spring Security提供了完整的访问控制机制,从而给应用安全设计提供了强大的支持。在介绍Spring Securi-ty对访问对象的访问控制整体框架的基础上,重点讨论了用户认证和基于URL的安全保护的访问授权的设置方法。并简要介绍了基于方法的安全保护及JSP页面内容的安全保护的配置及应用要点。 相似文献
124.
王长青 《南昌教育学院学报》2010,25(6):191-191
SIP是一种与HTTP类似的基于文本的协议。通过SIP可以减少各种应用特别是高级应用的开发时间。而且固定网运营商也已经逐渐地认识到SIP对于他们的深远意义。 相似文献
125.
目前,IPv6及相关协议已经相对成熟,然而,IPv4网络向IPv6网络的过渡和互通仍然是个艰巨的任务,直接影响了IPv6的发展。讨论了IPv4向IPv6过渡的3种基本技术,阐述了IPv4向IPv6分阶段过渡的流程。 相似文献
126.
随着流媒体技术的发展,实时传输协议RTP被广泛用于各种多媒体传榆系统中,为实时应用提供端到端的传输。可伸缩视频编码(SVC)因其时域、空间和质量的可分级,能够为用户提供可分级性更强的视频流,满足不同终端设备用户的需求。本文针对SVC视频流应用于NS2网络传输仿真而设计了一套可伸缩视频编码的RTP卦装方案,并将其应用于NS2仿真环境,实现了真实视频流的实时调度与传输。实验结果验证了该RTP卦装方案的正确性和有效性。 相似文献
127.
本文分析了OracleNet网络的体系结构,提出了基于目录服务器的OracleNet网络应用解决方案及具体实施方法。 相似文献
128.
在计算机内部和外部,统一总线标准和提高总线带宽一直是计算机发展的重要问题,本文从技术的角度介绍了PCI Express总线的基本拓扑结构和体系结构,并详细介绍了PCI Express总线的分层体系结构,然后对总线的协议开销来源,以及计算方法进行了详细的阐述,并结合实例进行了计算与分析。 相似文献
129.
The aim of this study was to establish the validity of the breakpoint in breathing frequency for the assessment of the lactate threshold and the ventilatory threshold during incremental running exercise. Twelve trained runners (mean +/- s: age 29 +/- 8 years; body mass 68.7 8.8 kg; V O 2m ax 57.9 +/- 4.1 ml . kg -1 . min -1 ) performed randomly assigned incremental treadmill tests on separate days. In addition to the assessment of the V O 2m ax (Test 1), the subjects performed two standard multi-stage treadmill tests (4-min stages) for the assessment of the lactate threshold while wearing (Test 2) and not wearing (Test 3) a standard mouthpiece and noseclip arrangement. Breathing frequency was measured by a thermistor, which was positioned in the back of the mouthpiece for Test 2, and fixed 3 cm in front of the mouth using a headband and flexible wiring for Test 3. All exercise tests were recorded on videotape and mean breathing frequency and stride rate were calculated for the last minute of each stage from real-time playback of the videotapes. The breathing frequency breakpoint was determined in six subjects only for Test 2 and in five subjects only for Test 3. For Test 2, there were no differences between the breakpoint in breathing frequency (14.7 +/- 0.9 km . h - 1), the lactate threshold (14.7 +/- 0.9 km . h -1 ) and the ventilatory threshold (14.7 +/- 1.1 km . h -1 ). For Test 3, the breakpoint in breathing frequency (14.0 +/- 1.0 km . h -1 ) was not appreciably different from the lactate threshold (14.7 +/- 1.2 km . h -1 ). Hey plots showed marked interindividual differences in the responses of breathing frequency and tidal volume to exercise. In four subjects, the ventilatory threshold was mediated by a non-linear increase in tidal volume, with breathing frequency either increasing in a linear manner (n = 1) or remaining constant owing to entrainment of breathing frequency to cadence (n = 3). We conclude that the breakpoint in breathing frequency does not provide a valid method for the field-based assessment of the lactate or ventilatory thresholds in most subjects for running exercise. 相似文献
130.