We demonstrate a technique for optically relaying and downconverting microwave signals. The system uses phase modulation in the transmitter and re-modulation and optical filtering in the receiver. Intermodulation dist...
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We demonstrate a technique for optically relaying and downconverting microwave signals. The system uses phase modulation in the transmitter and re-modulation and optical filtering in the receiver. Intermodulation distortion is suppressed by adjusting the amplitude of the local oscillator.
This paper deals with two different observers for sensorless DTC-controlled induction motor (IM) drives. First is sliding mode observer (SMO), second is extended Kalman filter (EKF). The main objective of this paper i...
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This paper deals with two different observers for sensorless DTC-controlled induction motor (IM) drives. First is sliding mode observer (SMO), second is extended Kalman filter (EKF). The main objective of this paper is experimental analysis of limits of these observers and their behavior in challenging low-speed region. Theoretical conclusions presented in this paper are verified by experiments made on designed IM drive prototypes of rated power of 250 W.
The design of modern embedded systems becomes more complex every day, due to the increasing amount of components and distinct functionalities incorporated into a single system. To address this situation, projects'...
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A frequency domain correlator (FDC) with low-complexity architecture is proposed. This signal processing module is part of FFT-based acquisition stage of a global position system (GPS). The FDC is based on a single re...
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A frequency domain correlator (FDC) with low-complexity architecture is proposed. This signal processing module is part of FFT-based acquisition stage of a global position system (GPS). The FDC is based on a single reconfigurable core capable of computing both decimation in frequency radix-2 (DIF-2) fast Fourier transform (FFT) and decimation in time radix-2 (DIT-2) inverse fast Fourier transform (IFFT). The proposed FDC reuses the reconfigurable core together with appropriate decimation choice, providing an improvement in resource management while avoiding any additional reorder data hardware. Additionally, the FDC architecture shows a great flexibility due to three levels of parameterization which allows to fix the number of complex input samples, data width and word format. The architecture has been implemented in Altera Cyclone II and Xilinx Virtex II Pro for N-points correlation with different word lengths. The simulation and synthesis results shows that the FDC is suitable for performing acquisition stage in GPS, enabling its utilization in software define radios.
In sensor networks, sensors are likely to be captured by attackers because they are usually deployed in an unprotected or even a hostile environment. If an adversarial compromises a sensor, he/she uses the keys from t...
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According to complexity of society,disaster has been *** a variety of disasters including natural,man-made,and social disasters has been happened frequently due to climate changes by industrialization,carelessness and...
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According to complexity of society,disaster has been *** a variety of disasters including natural,man-made,and social disasters has been happened frequently due to climate changes by industrialization,carelessness and misuse of human,terror,and *** alert system is important for preventing and mitigating of human victims from disasters. But diverse alert systems have been developed by own closed technology due to a lack of *** alert systems don't interworking with each other,so blind spot is generated caused of *** paper proposes alert network infrastructure and intelligent alert protocol to cooperate among heterogeneous disaster alert systems including especially civil defense alert system in Korea.
The copper metallization becomes more significant issue in a high frequency driving TFT-LCD with large sized panel. Since copper has a low adhesion force against the glass substrate, copper is inevitably used with an ...
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ISBN:
(纸本)9781617827020
The copper metallization becomes more significant issue in a high frequency driving TFT-LCD with large sized panel. Since copper has a low adhesion force against the glass substrate, copper is inevitably used with an aid of an adhesive metal layer such as Ti, Ta and Mo. When dissimilar metals like copper and molybdenum are exposed together in a wet etchant, a typical galvanic reaction occurs and this results in an undercutting of copper line or partial stains on the metal surface after drying. Especially, it is well-known that the suitable taper angle of Cu/Mo is difficult to obtain. Such failures often lead to a bad performance of thin film transistor and the display quality. Effect of acetic acid on wet galvanic corrosion behavior of DC magnetron sputtered the double layers of Mo and copper on the glass substrate has been examined. Addition of acetic acid in the copper etchant significantly reduced the galvanic current between copper and pure molybdenum.
The current researches to improve the reliability of operating systems have been focusing on the evolution of kernel architecture or protecting against device driver errors. In particularly, the device driver errors a...
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ISBN:
(纸本)9781424454273
The current researches to improve the reliability of operating systems have been focusing on the evolution of kernel architecture or protecting against device driver errors. In particularly, the device driver errors are critical to the most of the complementary operating systems that have a kernel level device driver. Especially on special purpose embedded system, because of its limited resources and variety of devices, more serious problems are induced. Preventing data corruption or blocking the arrogation of operational level is not enough to cover the entire problems. For examples, when using device drivers, the violation of function's call sequence can cause a malfunction. Also a violation of behavior rules on system level involves the same problem. This type of errors is difficult to be detected by the previous methods. Accordingly, we designed a system that traces system behavior at runtime and recovers optimally when errors are detected. We experimented in Linux 2.6.24 kernel operating on GP2X-WIZ mobile game player.
It is possible to reasonably measure the security quality of individual security patterns. However, more interesting is to ask: Can we show that a system built using security patterns is secure in some sense? We discu...
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ISBN:
(纸本)9781424458790
It is possible to reasonably measure the security quality of individual security patterns. However, more interesting is to ask: Can we show that a system built using security patterns is secure in some sense? We discuss here some issues about evaluating the security of a system built using security patterns. We consider the use of threats and misuse patterns to perform this evaluation.
We have studied effects of H atom source on deposition profiles of carbon films, deposited by H assisted anisotropic plasma CVD method. Deposition rate normalized by that for the aspect ratio of 1 at sidewall and bott...
We have studied effects of H atom source on deposition profiles of carbon films, deposited by H assisted anisotropic plasma CVD method. Deposition rate normalized by that for the aspect ratio of 1 at sidewall and bottom decreases with increasing discharge power of H atom source from 0 W to 500 W, because the incident H atom flux per surface area in a trench increases and H atoms etch carbon films.
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