Symbian OS v9.x引入了新的基于能力的系统安全模型,以构建一个可信计算平台。为了理解安全模型对应用开发的影响,深入分析了基于能力的安全模型,首先阐述了为什么进程是可信的基本单元,然后说明如何使进程和能力联系起来,并解释了相互...Symbian OS v9.x引入了新的基于能力的系统安全模型,以构建一个可信计算平台。为了理解安全模型对应用开发的影响,深入分析了基于能力的安全模型,首先阐述了为什么进程是可信的基本单元,然后说明如何使进程和能力联系起来,并解释了相互访问的可执行文件的能力应满足一定的关系。数据锁定实现了对重要数据的访问控制,而应用程序签名机制则保证只有合适的应用程序才能安装到手机上。对应用程序签名流程的简化和改进还需要进一步的研究。展开更多
Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synt...Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models.展开更多
An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform...An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.展开更多
文摘Symbian OS v9.x引入了新的基于能力的系统安全模型,以构建一个可信计算平台。为了理解安全模型对应用开发的影响,深入分析了基于能力的安全模型,首先阐述了为什么进程是可信的基本单元,然后说明如何使进程和能力联系起来,并解释了相互访问的可执行文件的能力应满足一定的关系。数据锁定实现了对重要数据的访问控制,而应用程序签名机制则保证只有合适的应用程序才能安装到手机上。对应用程序签名流程的简化和改进还需要进一步的研究。
文摘Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models.
基金The National Natural Science Foundation of China(No.61741102,61471164,61601122)the Fundamental Research Funds for the Central Universities(No.SJLX_160040)
文摘An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets.
