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We present a novel mobile code management environment,currently under design and development. Our design employs anopen architecture, suitable for ``plug-and-play' with COTS andother groups' tools. While we have studied new algorithms, costand objective functions, and other fundamental issues, the maincontribution of this experimental research work is in the environmentitself. It should be noted that networked platforms, such asthe World Wide Web, are inherently not suitable for traditional,predictable real-time applications. Thus, real-time concernsnecessarily need to be blended with others concerns, and thetarget applications, making use of our environment, will toobe a blend of partially hard real-time and partially (or mostly)soft-real- time ones. The prototype environment will thereforesupport performance-based analysis and management focusing notonly on predictability but also on compilation, efficiency, safetyand other tradeoffs. We have selected the Java language and itsbytecode format as a representation for mobile code as well asa language for our implementation. 相似文献
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In this paper we consider the potential of using an aggressive form of energy conservation for mobile computing environments. The estimators for the round-trip time and round-trip time variance used by TCP are used to direct the transceiver of a mobile node to idle over extended periods of time when packet activity is not anticipated. In addition, we consider data link layer extensions that provide additional control information allowing the mobile to be further selective as to when to idle and when to activate the network interface device. Simulations are conducted to examine the performance of the proposed scheme under various levels of congestion in the fixed part of the network, from completely unloaded to fully congested. The simulations reveal that the technique is promising but its effectiveness depends crucially on the control of the maximum window size used by TCP and on accurate knowledge of the congestion conditions in the network. 相似文献
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Vehicle Teleoperation Interfaces 总被引:1,自引:1,他引:0
Despite advances in autonomy, there will always be a need for human involvement in vehicle teleoperation. In particular, tasks such as exploration, reconnaissance and surveillance will continue to require human supervision, if not guidance and direct control. Thus, it is critical that the operator interface be as efficient and as capable as possible. In this paper, we provide an overview of vehicle teleoperation and present a summary of interfaces currently in use. 相似文献
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分析与研究矿井中频感应通信系统 ,并提出了一种新型的矿井中频数字感应通信系统。这种系统采用连续可变斜率增量调制 (CVSD)来实现语音信号的编码、GFM调制解调方式、FDMA、PLL频率合成器技术。本系统具有通话质量好、设备简单、抗衰减能力强等特点 ,适于矿井通信。 相似文献
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《Information Technology for Development》2012,18(4):iii-xxiii
ABSTRACTUsing data on major Indian states during 2001–2014, the paper analyzes the impact of AIM (Aadhaar, Inclusion and Mobile) trinity on economic growth. Using advanced panel data techniques, the evidence suggests that mobile penetration exerts a positive and statistically significant impact on economic growth. In addition, there exist strong complementarities between mobile telephony and financial inclusion. The magnitude of the complementarity is significantly higher in case of financial use as compared with financial access. In addition, the evidence points to the fact that biometric identification process (Aadhaar) is making its impact felt on financial inclusion, primarily by improving financial access. 相似文献
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丁凡 《长沙通信职业技术学院学报》2013,(4):14-18
文章对MIP及内容计费进行了详细的总结,并提出了中国电信移动网络HA/CCG的建设方案和策略,以及HA/CCG与周边系统的接口要求,能较好地指导电信运营商的准备工作和HA/CCG的网络建设. 相似文献