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To fit the demand of train speeding, existed railway should be widened, which causes the redistribution of the stress in the consolidated soft soil foundation that leads to unequal post-construction settlement, influences the stability of the roadbed. To eliminate above diseases, geogrid and plastic drainage plate usually be used. The paper uses FEM from aspects as layout manner, length, stiffness,...
This paper develops and experimentally tests the performance of a digital interconnection protection for grid-connected wind energy conversion systems (WECSs). The developed protection is constructed by two frequency frames to process voltages and currents measured at the point-of-common-coupling (PCC). The first frequency frame is set to process the d - q-axis components of the instantaneous 3Φ apparent...
Relativistic Mean Field (RMF) theory is applied to modern problems of nuclear structure, such as the description of rotating bands in super-deformed nuclei or the investigation of neutron halos in light exotic nuclei.
Ground faults are one of the major disruptions of the safety, stability, and economic operation of doubly fed induction generator (DFIGs)-based wind energy conversion systems (WECSs). On one hand, the minimization of possible damages caused by ground faults can be achieved by the accurate and reliable detection and identification of these faults. On the other hand, the fast response to ground faults...
In this paper, the performance of a passive anti-islanding method is experimentally tested for three phase (3φ) co-generation systems. The tested method is based on determining the wavelet packet transform (WPT) high frequency sub-bands present in the d — q-axis components of instantaneous 3φ apparent powers (sd and sq), when evaluated at the point of common coupling (PCC). This passive anti-islanding...
One of the requirements for safe, stable, sustainable, and profitable operation of doubly-fed induction generators (DFIGs)-based wind energy conversion systems (WECSs) is the accurate and reliable protection against electrical faults, in particular ground faults. The performance of protective devices employed to achieve this requirement is highly dependent on the grounding configuration of the DFIG-based...
This paper investigates the fuzzy control method for the linear switched reluctance motor (LSRM) drive system. Modeling of the LSRM is constructed based on the finite element method (FEM) environment Maxwell and the control system is analyzed by the co-simulation environment with Simplorer. Both the performance of the fuzzy proportional integral differential (PID) controller and the traditional PID...
A combination of Newton iterations and phaselet tight frames allows calculating the power factor of a single phase load. In this paper, the real-time implementation and experimental testing of the Newton-phaselet method are presented. The tested method is structured to employ the Newton iterations in order to estimate values for the apparent power S, and to utilize phaselet tight frames to calculate...
Synchrotron-based X-ray fluorescence computed tomography (XFCT) is a common technique for mapping metal ions in biological specimens. In recent years, it has been demonstrated that various metal ions could play critical roles in disease and general biological functions. In this work, we are developing a benchtop x-ray fluorescence emission tomography system that utilizes combines charge-coupled device...
Synchrotron-based X—ray fluorescence computed tomography (XFCT) is a relatively new medical imaging platform that can be used for effectively mapping indicative pathologies of metals such as copper or magnesium in Parkinson's disease and other neurodegenerative disorders [1]. At the present, the sensitivity from these potential in vivo systems is limited due to (a) the intrinsically low interaction...
Performance-based contracting (PBL), as a novel approach, is replacing traditional service procurement practices. In this paper, we set up a closed-loop support system for repairable parts with an M/M/m/N queuing service facility and a spare parts warehouse. We derived the steady-state probability of inventory levels in warehouse and the performance measures of the support system. Under the performance-based...
An algorithm on the estimation of DOA with unknown number of signal sources and suitable for parallel real-time computation is presented in this paper. According to the theory of adaptive beamforming and LMS or RLS fast iteration algorithm, the nulls which represent directions of signals are formed at the appropriate positions on array antenna beam pattern in the new algorithm. The computer simulation...
Advantages of Anisotropic Conductive Films (ACF) technology, especially the low bonding temperature, fine pitch capability, elimination of lead and low cost, have resulted in ACF interconnects being widely used in contemporary portable electronic devices. Such products are exposed to various types of mechanical loadings, such as shock and impact during handling and accidental drops, throughout their...
In this paper the shock impact reliability of a MEMS microphone is studied through experiments and finite element simulations. The maximum acceleration tolerance of the device is studied and the effect of shock impact orientation is also investigated. Finite element method is employed to determine the potential failure locations of the MEMS structure. Several challenges of the modeling process, such...
This paper presents the basic design of a dual-mode readout system for MR-Compatible ultrahigh resolution SPECT/PET system, especially the design of a cathode waveform sampling and processing unit. This effort was motivated by the development of a stationary CdTe detector based MR-Compatible SPECT system. In our previous study, this CdTe detector shows around 3kev energy resolution around 140kev for...
In this paper, we will present the design and preliminary performance of an ultrahigh resolution stationary MR compatible SPECT (MRC-SPECT) system that is developed in our lab. The MRC-SPECT system is based on the second-generation energy-resolved photon-counting (ERPC) CdTe detectors and there are several key features associated with this system. Firstly, up to a total of twenty ERPC detectors will...
Durability and reliability assessment is a key aspect of new product development. The focus of this paper is to assess the durability of the electrical joint of a PV product by examining its fatigue life under cyclic temperature excursions experienced throughout the product life cycle. An in progress method is presented for product life prediction as function of its deployment location. The life prediction...
Failures under dynamic mechanical stresses caused by impact and drop loading are an important concern when assessing the durability of portable, hand-held electronic products. This study focuses on failures in COTS MEMS packages on PWAs, due to repeated drop and impact events. This MEMS component uses a system-in-package (SIP) configuration, consisting of a MEMS microphone chip and an ASIC signal...
Failure under dynamic mechanical stresses caused by impact and drop loading is a critical concern for reliability of surface mount components in portable electronic products. This study focuses on drop-induced failures in system-in-package (SIP) COTS Micro-Electro-Mechanical Systems (MEMS) components that are mounted on PWAs. In particular, we are interested in the effects of secondary impacts that...
This paper presents the design and experimental results obtained with a prototype adaptive SPECT that implements a recently developed adaptive angular sampling approach. With this system, the hardware system configuration can be adjusted in real time based on the imaging information being collected to offer an optimum sampling of an unknown object. This system consists of two major components. First,...
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