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High Q optomechanical cavity is demonstrated based on silicon nanobeam structure with mechanical frequency of 4.52GHz. The mechanical Q can reach 24500 with the help of optical spring effect, which is record-high in ambient environment.
We demonstrate an on-chip integrated Cherenkov radiation (CR) emitter, in which the no-threshold CR could be realized and a broadband CR is observed with electron energy of only 0.25–1.4keV.
This paper considers the stabilization problem for a harmonic oscillator system under positive delayed velocity feedback control. By using the τ-decomposition technique and imposing a simple constraint on the feedback gain, some necessary and sufficient conditions are established such that the harmonic oscillator can be globally asymptotically stabilized if and only if the time-delay for the control...
Medical institutes use Electronic Medical Record (EMR) to record a series of medical events, including diagnostic information (diagnosis codes), procedures performed (procedure codes) and admission details. Plenty of data mining technologies are applied in the EMR data set for knowledge discovery, which is precious to medical practice. The knowledge found is conducive to develop treatment plans, improve...
The resonant stability problems of LCL filter have become big challenges for grid-connected inverter in weak grid. This paper takes the effect of non-minimum phase time delay on the ratio between resonance frequency and sampling frequency into account and use it to design the LCL filter. Both LCL resonance frequency and inverter-side inductor and filter capacitor related L1C resonance frequency are...
This paper considers the pinning synchronization problem for complex networks with directed topologies by utilizing the output state information of network nodes, where the node dynamics satisfies the Lipschitz condition. Based on M-matrix theory and Lyapunov functional method, some sufficient conditions are derived to ensure that the network can be pinned to the trajectory of the leader node. Some...
Mobile applications that provide ever-changing information such as social media and news feeds applications are designed to consistently update their contents in the background. This operation, often called “prefetching”, provides the users with immediate access to up-to-date contents. However, such updates often result in the unwanted side-effect of draining the battery of mobile devices. It is considered...
The accurate detection of region(s)-of-interest (ROI) via Active Contour Method (ACM) is a well-known and evolving research topic in image segmentation. A novel region-based active contour method is proposed that can segment real and synthetic images with blurred borders more efficiently. Additionally, a new Signed Pressure Force (SPF) function named as Hyperbolic Trigonometric Signed Pressure Force...
The purpose of this paper is to study the temperature effect on the Print Circuit Board (PCB) and the solder joints in the vehicle under working condition of the engine. Thermal-stress test has been used to evaluate the reliability or fatigue life of the PCB using commercially available Finite Element Analysis software, ANSYS. The thermal deformation distribution of the PCB and stress of the solder...
In view of multifarious power quality problems in the electrical railway power system (ERPS), an asymmetrical connection balance transformer (ABT)-based power quality control system (ABT-PQCS) is presented in this paper. The back-to-back converter which is connected to the system through the step-down transformer can eliminate the negative sequence current (NSC), compensate reactive power at the same...
As the expected emerging Non-Volatile Memory (NVM) technologies, such as 3DXPoint, are in production, there has been a recent push in the big data processing community from storage-centric towards memory-centric. Generally, in large-scale systems, distributed memory management through traditional network with TCP/IP protocol exposes performance bottleneck. Briefly, CPU- centric network involves context...
In distribution network, with the installed of photovoltaic (PV), bought many problems. One of the most concerned problems is the overvoltage in the terminal bus of distribution network. It is caused by the reverse power flow which brought out by the increase of the PV sources penetration. In this paper, an improved PQ-Q (V) control strategy is proposed to alleviate such problem. The economic performance...
This paper proposes how to conduct the specific job performance optimization of Hive and Spark SQL, and make a comparison of them at the same time. First, we compare Hive and Spark SQL by ten SQL queries. By analyzing the impact of different file formats and compression strategies on the performance in different query types, we conclude that Spark SQL can better support Parquet, while it does not...
This paper proposed a difference of standard deviation operator to detect temporal changes in multi-temporal Radarsat-1 SAR images which is derived from the classical multiplicative model. When changes are occurred, textures of the terrestrial surface will be modified resulting in the variation of standard deviation of the terrestrial surface. The new Riemannian metric is introduced into the unsupervised...
This paper presents a variational method for SAR image segmentation that unifies boundary- and region-based information into the geometric active contour model. A new Riemannian metric is introduced to construct region-based energy function derived by maximizing the geodesic distance of a new Riemannian metric in differential-geometric structure for spectral density functions. A heterogeneity indicator...
Both traditional coarse-grained and fine-grained Flash Translation Layer schemes are unsuitable for ultra-large SSDs. They produce overmuch mapping entries which fail to be kept in embedded DRAM completely and can suffer severely from low spatial and temporal localities. In this paper, we propose a novel KV-FTL for ultra-large SSDs, which mostly maps logical addresses to physical addresses via a simple...
Functional Resonance Analysis Method (FRAM) is a kind of system safety analysis method, which can deal with the problems of nonlinear system[1–3]. This paper tries to develop FRAM into a dynamic research and analysis model because that FRAM can only be used as artificial static system analysis. In the development of FRAM dynamic model, the fact that accident investigators pay more attention to the...
The randomness of wind energy and its uncertainty of forecasting have caused serious power quality problems, which restrain the further development of wind farms. Therefore, it is a hot topic to research and solve the power quality problems of wind farms. This paper describes the important aspects of power quality problems about the voltage fluctuations and flicker, harmonic, voltage deviation of...
The existing power system fault analysis method is based on the information of power system relay protection and sensor device to determine the location and type of fault. With the continuous expansion of the power system and the increasing complexity of the structure, excessive alarm information makes it difficult to diagnose the power system faults timely and effectively. A fault diagnosis method...
This paper is concerned with finite-time synchronization for two models of coupled Cohen-Grossberg neural networks with time-varying delays. In the first one, linearly coupled Cohen-Grossberg neural networks is considered. In the second one, nonlinearly coupled Cohen-Grossberg neural networks is discussed. Based on finite-time stability theory, some inequality techniques, and designed controllers,...
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