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941.
低功耗温室无线测量节点的设计 总被引:5,自引:0,他引:5
为了提高温室环境参数的监测效果,采用射频SoC芯片nRF9E5、数字温湿度传感器SHT11及光强度传感器TSL2560D,设计了无线温湿度及光照度监控系统的测量节点;并根据无线通信系统的特点设计了系统的软硬件结构,其低功耗无线传输模式降低了节点的能耗.经调试和试验运行,系统具有可靠性高、使用方便、通信节点容量易扩展等优点,这对较大空间的温湿度及光照度的监控具有良好的应用价值. 相似文献
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944.
该文分析了作战行动建模资源库的特点,确定了基于WEB的分布式作战行动建模资源库系统的体系结构和功能,选取了XML描述资源元数据信息,并提出了基于本体的智能搜索引擎。 相似文献
945.
基于嵌入式视频存储的特点,分析目前已有的文件系统在视频应用上的不足,提出了适合硬盘录像机的专用文件系统设计方案,并从数据存储、检索、读取和恢复等方面阐述了设计思想及具体实现。经过在相关产品上的应用,表明该文件系统可以实现高效、安全的视频存储。 相似文献
946.
基于蚁群算法的网格资源发现模型研究 总被引:1,自引:0,他引:1
本文通过对传统的网格资源发现存在的问题进行分析,针对其不足,引入蚁群算法,提出基于蚁群算法的网格资源发现模型(AA_GRRM),设计并分析AA_GRRM的体系结构,并对其关键模块分析设计,以提高网格资源发现效率。 相似文献
947.
Space robotic systems are expected to play an increasingly important role in the future on-orbit service. The applications
include repairing, refueling or de-orbiting of a satellite, or removal of the space debris. The dynamical performances of
space robotic system result from the multi-physics interactions between mechanical, electrical, electronic, control, etc.
In this paper, we developed a unified multi-domain modelling and simulation system. The system is composed of the following
modules: the path planner, joint controllers, motor and its driver, gearing mechanism of the space manipulators, the Guidance,
Navigation, and Control (GNC) system, the actuators of the base, and the orbital environment, orbital dynamic and the multi-body
dynamic of the whole system, etc. Based on this system, the operation during different stages, including far range rendezvous,
close range rendezvous (is usually divided into two sub-phases: closing and final approach) and target capturing can be studied
from the view of multi-physics domains. The key algorithms, such as pose (position and attitude) measurement, GNC of the base,
path planning and control of the space manipulator, and so on, can be validated using the system. As examples, the capturing
processes of a moving target under free-floating and attitude-controlled modes are simulated and the simulation results are
given. 相似文献
948.
A common and critical operation for wireless sensor networks is data gathering. The efficient clustering of a sensor network that can save energy and improve coverage efficiency is an important requirement for many upper layer network functions. This study concentrates on how to form clusters with high uniformity while prolonging the network lifetime. A novel clustering scheme named power- and coverage- aware clustering (PCC) is proposed, which can adaptively select cluster heads according to a hybrid of the nodes' residual energy and loyalty degree. Additionally, the PCC scheme is independent of node distribution or density, and it is free of node hardware limitations, such as self-locating capability and time synchronization. Experiment results show that the scheme performs well in terms of cluster size (and its standard deviation), number of nodes alive over time, total energy consumption, etc. 相似文献
949.
Extended object model for product configuration design 总被引:1,自引:1,他引:0
This paper presents an extended object model for case-based reasoning (CBR) in product configuration design. In the extended object model, a few methods of knowledge expression are adopted, such as constraints, rules, objects, etc. On the basis of extended object model, case representation model for CBR is applied to product configuration design system. The product configuration knowledge can be represented by the extended object. The model can support all the processes of CBR in product configuration design, such as case representation, indexing, retrieving, and case revising. The presented model is an extension of the traditional object-oriented model by including the relationship class used to express the relation between the cases, constraints class used in the product configuration knowledge representation, index class used in case retrieving, and solution class used in case revising. Therefore, the product configuration knowledge used in the product configuration design can be represented by using this model. In the end, a metering pump product configuration design system is developed on the basis of the proposed product configuration model to support customized products. 相似文献
950.
Jun Liang Long Chen Xian-yi Cheng Xian-bo Chen 《Simulation Modelling Practice and Theory》2010,18(8):1092-1103
Distance-between-vehicle-measurement is the only factor in traditional car rear-end alarm system. To address the above problem, this paper proposes an alarming model based on multi-agent systems (MAS) and driving behavior. It consists of four different types of agents that can either work alone or collaborate through a communications protocol on the basis of the extended KQML. The rear-end alarming algorithm applies the Bayes decision theory to calculate the probability of collision and prevent its occurrence real-time. The learning algorithm of driving behavior based on ensemble artificial neural network (ANN) and the decision procedure based on Bayes’ theory are also described in this paper. Both autonomy and reliability are enhanced in the proposed system. The effectiveness and robustness of the model have been confirmed by the simulated experiments. 相似文献