A5083894909- Photonic and Optical Devices
- Advanced Fiber Optic Sensors
- Power Quality and Harmonics
- Geochemistry and Geologic Mapping
- Hydrocarbon exploration and reservoir analysis
- Advanced Aircraft Design and Technologies
- Intergenerational Family Dynamics and Caregiving
- Dementia and Cognitive Impairment Research
- Magnetic Properties and Applications
- Aeroelasticity and Vibration Control
- Mechanical and Optical Resonators
- Machine Fault Diagnosis Techniques
- Aerodynamics and Fluid Dynamics Research
- High voltage insulation and dielectric phenomena
- Mineral Processing and Grinding
- Advanced Measurement and Metrology Techniques
- Geriatric Care and Nursing Homes
- Image and Signal Denoising Methods
- Power Systems Fault Detection
- Power Transformer Diagnostics and Insulation
- Electric Motor Design and Analysis
Virginia Tech
1999-2017
National University of Defense Technology
2008
This paper presents self-calibrated interferometric-intensity-based optical fiber sensors, which combine for the first time interferometry and intensity-based devices into a single sensor system. The involves an extrinsic Fabry-Perot (FP) interferometric cavity. broadband light returned from FP cavity is split two channels in such way that one channel has coherence length much longer than doubled air-gap separation so generates effective interference, while other short no interference takes...
This article develops a method to detect and classify power quality problems using novel combination of digital filtering, wavelets artificial neural networks. The is developed for voltage waveforms arbitrary sampling rate number cycles, large variety events simulated with MATLAB(R) software, in addition sampled from utility monitoring EMTP(R) simulations. Power system monitoring, augmented by the ability automatically characterize disturbed signals, powerful tool engineer use addressing...
This paper discusses the steady-state harmonic modeling and simulation of a cycloconverter drive system (CDS). The operation control synchronous motor load were modeled in time domain. Based on duality principle electric magnetic circuits, four types three-phase transformer models with detailed nonlinear magnetizing characteristics implemented. behaviors entire studied under several worst conditions. goal this is to understand problems associated CDS from an integrated point view, special...
A combined artificial neural network and expert system tool (ANNEPS) is developed for transformer fault diagnosis using dissolved gas-in-oil analysis (DGA). ANNEPS takes advantage of the inherent positive features each method offers a further refinement present techniques. The knowledge base its (EPS) derived from IEEE IEC DGA standards experiences to include as many known rules possible. topology training data set (ANN) are carefully selected extract well unknown correlations implicitly....
A novel pseudo working-point control measurement scheme for the acoustic sensitivity of interferometric fiber-optic hydrophones is described and demonstrated. The principle introduced in detail. An experimental system, which interrogates an hydrophone with this method, designed. pressure phase measured over frequency range 20-2500 Hz. about -156.5 dB re 1 rad/μPa a fluctuation lower than ±2 dB, good agreement results obtained by method generated carrier. testify validity new has advantages...
In this paper, we present and compare numerical experimental studies of the flowfield around a configuration consisting an inboard wing mounted between twin fuselages. The results both show that behind doublefuselage virtual wing-tip vortex system forms. trailing for twin-fuselage is shed from fuselages as well edge wing. vorticity combines with in manner very similar to what happens conventional single-fuselage configuration. are qualitative agreement. Introduction aviation industry has...
Researchers have assumed without controversy that providing care for a family member with dementia is hazardous the caregivers’ health. Although great strides been made in last two decades understanding how caregiving stressors upset physiological processes and proliferate into chronic health conditions, it not known if also leads to early mortality. In current study, we utilize longitudinal data collected from 106 primary caregivers of persons diagnosed Mild Cognitive Impairment during Wave...