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In this paper, we will study the optimal control problem of a system containing a differential integral (D-I) operator. We will deduce the necessary optimality conditions and apply it first to the problem of minimum energy to find the lowest energy for an electrical circuit containing a resistor, a coil and a capacitor (RLC circuit), and second to the problem of the minimum time to transfer electrical current in RLC circuit from one state to another in the shortest possible time. [ABSTRACT FROM AUTHOR]

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Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Timed-release encryption( TRE) is a cryptography that studies the problem of sending information into the future,it can solve many practical problems to construct a feasible and safe TRE. This paper proposed a scheme based on the research of indistinguishability obfuscation and TRE. This scheme encapsulated the sender’s encryption and receiver’s decryption by a circuit and obfuscated this circuit by an indistinguishability obfuscator. It could make great use of the time of obfuscators obfuscate circuits,simplified the scheme and improved the security of this scheme. Finally,this paper proves the correctness and security of this TRE scheme. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Performing mass spectrometry (MS) in a low-vacuum environment not only substantially reduces the cost, size, weight and power of the instrument but also expands its applicability, making it is more suitable for field applications such as marine applications. As it is a complicated instrument, simulation is a critical step in the development process of a mass spectrometer. The Langevin collision model describes the interaction between low-energy particles. By introducing the Langevin collision theory to the simulation of low-vacuum ion motion, the movement of discrete ions can be more accurately described and the influence of different operational models on the performance of MS can be evaluated. Based on Langevin collision model, a low-vacuum simulation platform of cylindrical ion trap (CIT) was built in COMSOL Multiphysics. The influence of frequency of the radio frequency (RF) voltage V, amplitude of the radio frequency (RF) voltage ω and size of the ion trap r0 on the sensitivity and resolution of MS were investigated. The simulation results showed that by applying a high-frequency RF voltage, a spectral peak with a narrower width and a larger signal strength could be obtained and thus higher sensitivity and resolution were obtained. This is because when the frequency of the RF voltage is enhanced, the ion acquires more energy from the quadrupole within a unit time, which increases the moving velocity and enhances the collisional capability of the ions. When ω increases, in order to keep Mathieu parameter q unchanged, V must be increased with the square of ω or decrease r0 proportionally. The value of V is determined by the electric circuit, and it is very difficult to increase it significantly. Moreover, a high voltage can cause discharge. Therefore, from this perspective, in order to use a larger RF frequency ω, the size of the ion trap r0 must be reduced. Thus, it is concluded that by increasing the frequency of the radio frequency voltage while reducing the size of the ion trap, mass analysis can be conducted under a low vacuum. Additionally, the results was applied to experiments and obtained excellent spectral graphs of organic compounds under a maximum pressure of 2 Pa in another paper, which proved the effectiveness of the conclusions obtained from the simulation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan University of Science & Technology, Natural Science is the property of Editorial Office of Journal of Henan University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A variety of heterogeneous electronic equipment were difficult to integrated with each other in intelligent home system, this paper adopted a universal plug and play standard to integrate the service robot into the intelligent home system, emphatically introduces the new derivative service. Firstly, it introduced the details of UPnP standard and service robot Rovio. Then, it developed a PC application program as the virtual bridge between the service robot and intelligent home network, and formed a control circuit to control the service robot to provide service for intelligent home system. Finally, it used some practical operation to test the performance of the UPnP Rovio virtual bridge, and demonstrate the possibility of the integration between service robot and intelligent home network by the practical services, such as path tracking, rubbish monitoring and so on, especially, the advanced services show that the huge potential benefits are expected. [ABSTRACT FROM AUTHOR]

The lifespan of the output filter electrolytic capacitor in general lighting LED power supply doesn't match LED's long lifespan. In this regard, this paper proposed the LED driver circuit based on Buck with active ripple compensation. In the circuit, the active ripple compensation branch was used to replace the output filter electrolytic capacitor to offset the inductor ripple current, so that the LED array can obtain a constant DC and achieve the ideal drive state of the LED. In order to reduce the losses of the ripple compensation branch, the peaks and valleys of the inductor current must be controlled and the hysteresis current control can effectively meet that requirement. The LED power supply based on Buck with active ripple compensation and hysteresis current control was designed and made which output power was 30 W. According to the simulation and experiment results, the proposed new power supply is feasible. [ABSTRACT FROM AUTHOR]

In order to solve the problem of big difference between simulation process and actual application process this paper takes the signal filtering in electrical circuit system as an example, to present a design method of digital filtering system. Using relevant modules provided by the software of SIMULINK/SIMSCAPE, some electrical circuits are built, and combing some programming skill, triggered subsystem from SIMULINK modules is used to simulate the process of periodical sampling, periodic calculation of difference equation. Furthermore, relevant programming idea is introduced by the implement of a first order low pass filter. Finally, simulation results show the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

With regard to the electromagnetic interference and power loss generated in the operation of the switches in switched reluctance motor drive ( SRD ) system, the paper proposed a converter with a new kind of capacitor divider parallel resonant DC link( CDPRDCL). The converter was to realize the zero-voltage-turn-off of the phase switches by connecting one buffer capacitor to each switch in conventional asymmetric inverters; and to realize the zero-voltage-turn-on of the phase switches, and the soft operation of the resonant switches, by adding a resonant link containing, as the main components, two inductors and one capacitor and through reasonably controlling the resonant switches in this link. The required condition for soft-switching was obtained by analyzing the working principle and operation process of the circuit. The soft-switching converter with such a resonant link has a larger effective interval and a lower power loss,thereby enhancing the efficiency and performances of SRD. Finally,the validity and efficiency of the converter are verified by MATLAB simulation. [ABSTRACT FROM AUTHOR]

This paper firstly expounded the principles of EHW and introduced the current status at home and abroad. Then it presented the important steps of EHW. Lastly it put forward the existing problems and the improvement directions. Fault self-repair based on EHW will have bright prospect and great value in engineering application [ABSTRACT FROM AUTHOR]

To solve the problems of complex fault location process and heavy workload before test using traditional large-scale circuit fault diagnosis methods in the multi-fault conditions, this paper presented a new approach for fault diagnosis using group decomposition. Low dimensional fault eigenvectors could be acquired by decomposing the large-scale analogue circuit in accordance with its topological property and group decomposition criteria. Based on ideas of pattern recognition, neural network which had highly parallel classify capability was selected as classifier and wavelet function which had fast convergence property was selected as hidden layer's transfer excitation function. The simulation results show that this method can achieve fast fault feature vector classification and fault diagnosis results. Comparing with the existing multiple-test-condition (MTC) method and intersection tearing method, this approach has smaller amount of work before test, fewer diagnostic times, less computation, better capability of diagnosing multiple faults and stronger engineering practicality. [ABSTRACT FROM AUTHOR]