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Full-Text Articles in Physical Sciences and Mathematics

Assured Android Execution Environments, Brandon P. Froberg Mar 2018

Assured Android Execution Environments, Brandon P. Froberg

Theses and Dissertations

Current cybersecurity best practices, techniques, tactics and procedures are insufficient to ensure the protection of Android systems. Software tools leveraging formal methods use mathematical means to assure both a design and implementation for a system and these methods can be used to provide security assurances. The goal of this research is to determine methods of assuring isolation when executing Android software in a contained environment. Specifically, this research demonstrates security properties relevant to Android software containers can be formally captured and validated, and that an implementation can be formally verified to satisfy a corresponding specification. A three-stage methodology called "The …


Research On Power-Frequency Electromagnetic Interference Model Of Multicore Twisted Signal Cable Of High-Speed Railway, Bowen Zhang, Jiangjian Xie, Zhixin Wang, Jin Yang, Hao Yan Jan 2018

Research On Power-Frequency Electromagnetic Interference Model Of Multicore Twisted Signal Cable Of High-Speed Railway, Bowen Zhang, Jiangjian Xie, Zhixin Wang, Jin Yang, Hao Yan

Turkish Journal of Electrical Engineering and Computer Sciences

With the increase in the traction power of high-speed railways, the power-frequency electromagnetic interference of traction current to the signal cables becomes increasingly more severe. In this paper, the calculation model of the magnetic interference to signal cable was established on the MATLAB/Simulink platform based on the multiconductor transmission line theory. This model took SPTYWPL03-8B 8-core twist signal cable as an example and the power-frequency interference of external current to the signal cable was analyzed theoretically. In addition, experiments on electromagnetic interference of double-ended and single-ended signal cables were performed to validate the simulation model. Experiments showed that the relative …


A New Semianalytical Method For Analysis Of The Disc-Type Permanent Magnethysteresis Motor In Steady-State Operational Conditions, Ali Behniafar, Ahmad Darabi Jan 2018

A New Semianalytical Method For Analysis Of The Disc-Type Permanent Magnethysteresis Motor In Steady-State Operational Conditions, Ali Behniafar, Ahmad Darabi

Turkish Journal of Electrical Engineering and Computer Sciences

Considering the characteristics of hysteresis and permanent magnet motors, it seems that these two motors are complements of each other. Thus, their combination yields a motor with an excellent performance. In order to preserve the major advantages of both motors in the new motor, a disc-type slotless structure is chosen. This paper presents a new finite-element method for the modeling of disc-type permanent magnet hysteresis synchronous (PMHS) motor. In this modeling method a new iterative algorithm is used. Programming software has been linked to finite- element software because of its limitation in the modeling of hysteresis phenomena. Validity of the …


Rlgc(F) Modeling Of A Busbar Distribution System Via Measured S-Parameters Atcenelec And Fcc Bands, Zeynep Hasirci, İsmai̇l Hakki Çavdar, Mehmet Öztürk Jan 2018

Rlgc(F) Modeling Of A Busbar Distribution System Via Measured S-Parameters Atcenelec And Fcc Bands, Zeynep Hasirci, İsmai̇l Hakki Çavdar, Mehmet Öztürk

Turkish Journal of Electrical Engineering and Computer Sciences

This paper addresses the extraction of accurate frequency-dependent per-unit-length RLGC parameters for busbar distribution systems using measured S-parameters for the CENELEC and FCC bands. A busbar is a distribution system element (three phase, low voltage) with a modular structure that carries electrical energy in buildings. The S-parameters of a busbar distribution system at different current levels (630 A, 1250 A, 2000 A) are measured with a vector network analyzer and then analyzed for three different two-port connections (L1-N, L2-N, L3-N). A frequency- dependent RLGC(f) model is used to characterize the busbar as a transmission line using a derivative-free optimization algorithm. …