1,380 research outputs found

    AUTOMATED SYNTHESIS OF VIRTUALBLOCKS FOR INTERFACING SYSTEM UNDER TEST

    Get PDF
    In this thesis, I/O signal recognizers, called VIRTUALBLOCKS, are synthesized to interface with a SYSTEM UNDER TEST (SUT). Methods for automated synthesis of virtualblocks allow us to simulate environment interfaces with SUT and also perform fault detection on SUT. Such methods must be able to recognize incoming sequences of signals from SUT, and upon the signal recognition determine the proper outgoing sequences of signals to SUT. We characterize our systems into four distinctive systems: system under test, AUXILIARY SYSTEM, controller and external environment. The auxiliary system is represented as a form of condition system Petri net (virtualblocks) and interacts with SUT along with the interaction among the controller and the external environment. Fault detection is performed by subsystems called DETECTBLOCKS synthesized from the virtualblocks. We present construction procedures for virtualblocks andamp; detectblocks and discuss the notion of LEGALITY and DETECTABILITY. Finally, we illustrate our approach using a model of a scanner control unit

    Trinomial coefficients and matrices over finite fields

    Full text link
    In this paper, using the tools of trinomial coefficients we study some arithmetic properties of certain determiants involving reciprocals of binary quadratic forms over finite fields

    Structural Health Evaluation of Arch Bridge by Field Test and Optimized BPNN Algorithm

    Get PDF
    Arch bridges play an important role in rural roads in China. Due to insufficient funds and a lack of management techniques, many rural arch bridges are in a state of disrepair, unable to meet the increasing transportation needs. Thus, it is of great significance to develop a set of rapid and economic damage identification procedures for the management and maintenance of old arch bridges. Sanliushui Bridge, located in Chenggu County, Hanzhong, is selected as a model case. Field tests and numerical simulations were carried out to identify the damage states of Sanliushui Bridge. The sum square of wavelet packet energy change rate, a damage identification index based on wavelet packet analysis method was implemented to process the measured data of the load test and the simulated data of the numerical calculation model with assumed damage. BPNN, GA-BPNN, PSO-BPNN and test data analysis are adopted to compare the measured data with the simulated data to quantitatively identify the damage degree of the selected bridge. By comparing the results of the two methods mentioned above, it is found that the proposed damage identification approach realized a precise damage identification of the selected arch bridges

    Global enhancement of cortical excitability following coactivation of large neuronal populations

    Get PDF
    Correlated activation of cortical neurons often occurs in the brain and repetitive correlated neuronal firing could cause long-term modifications of synaptic efficacy and intrinsic excitability. We found that repetitive optogenetic activation of neuronal populations in the mouse cortex caused enhancement of optogenetically evoked firing of local coactivated neurons as well as distant cortical neurons in both ipsilateral and contralateral hemispheres. This global enhancement of evoked responses required coactivation of a sufficiently large population of neurons either within one cortical area or distributed in several areas. Enhancement of neuronal firing was saturable after repeated episodes of coactivation, diminished by inhibition of N-methyl-D-aspartic acid receptors, and accompanied by elevated excitatory postsynaptic potentials, all consistent with activity-induced synaptic potentiation. Chemogenetic inhibition of neuronal activity of the thalamus decreased the enhancement effect, suggesting thalamic involvement. Thus, correlated excitation of large neuronal populations leads to global enhancement of neuronal excitability
    corecore