Multi-Input Source, Looped Systems

2008 ◽  
pp. 197-212
Keyword(s):  
Input Source

Kirchhoff migration using eikonal-based computation of traveltime source derivatives

Geophysics ◽  
2013 ◽  
Vol 78 (4) ◽  
pp. S211-S219 ◽  
Author(s):  
Siwei Li ◽  
Sergey Fomel
Keyword(s):  
Differential Equation ◽  
Eikonal Equation ◽  
Order Partial Differential Equation ◽  
Fast Marching ◽  
First Order ◽  
Velocity Models ◽  
Kirchhoff Migration ◽  
Input Source ◽  
First Arrival ◽  
Synthetic Models

The computational efficiency of Kirchhoff-type migration can be enhanced by using accurate traveltime interpolation algorithms. We addressed the problem of interpolating between a sparse source sampling by using the derivative of traveltime with respect to the source location. We adopted a first-order partial differential equation that originates from differentiating the eikonal equation to compute the traveltime source derivatives efficiently and conveniently. Unlike methods that rely on finite-difference estimations, the accuracy of the eikonal-based derivative did not depend on input source sampling. For smooth velocity models, the first-order traveltime source derivatives enabled a cubic Hermite traveltime interpolation that took into consideration the curvatures of local wavefronts and can be straightforwardly incorporated into Kirchhoff antialiasing schemes. We provided an implementation of the proposed method to first-arrival traveltimes by modifying the fast-marching eikonal solver. Several simple synthetic models and a semirecursive Kirchhoff migration of the Marmousi model demonstrated the applicability of the proposed method.

A MALAY TEXT CORPUS ANALYSIS FOR SENTENCE COMPRESSION USING PATTERN-GROWTH METHOD

2016 ◽  
Vol 78 (8) ◽  
Author(s):  
Suraya Alias ◽  
Siti Khaotijah Mohammad ◽  
Gan Keng Hoon ◽  
Tan Tien Ping
Keyword(s):  
Text Summarization ◽  
Corpus Analysis ◽  
Text Corpus ◽  
Sentence Compression ◽  
Condensed Representation ◽  
Pattern Growth ◽  
Growth Method ◽  
Document Collection ◽  
Input Source ◽  
Confidence Value

A text summary extracts serves as a condensed representation of a written input source where important and salient information is kept. However, the condensed representation itself suffer in lack of semantic and coherence if the summary was produced in verbatim using the input itself. Sentence Compression is a technique where unimportant details from a sentence are eliminated by preserving the sentence’s grammar pattern. In this study, we conducted an analysis on our developed Malay Text Corpus to discover the rules and pattern on how human summarizer compresses and eliminates unimportant constituent to construct a summary. A Pattern-Growth based model named Frequent Eliminated Pattern (FASPe) is introduced to represent the text using a set of sequence adjacent words that is frequently being eliminated across the document collection. From the rules obtained, some heuristic knowledge in Sentence Compression is presented with confidence value as high as 85% - that can be used for further reference in the area of Text Summarization for Malay language.

scholarly journals Experimental Study of Various Parameters during Speed Control of Three-phase Induction Motor Using GPIC and LabVIEW

2021 ◽  
Vol 5 (1) ◽  
pp. 51-62
Author(s):  
Adnan Ahmed ◽  
Abdul Majeed Shaikh ◽  
Muhammad Fawad Shaikh ◽  
Shoaib Ahmed Shaikh ◽  
Jahangir Badar Soomro
Keyword(s):  
Induction Motor ◽  
Induction Motors ◽  
Induction Machine ◽  
Speed Control ◽  
Industrial Applications ◽  
General Purpose ◽  
Three Phase ◽  
Field Programmable ◽  
Input Source ◽  
Open Control

Induction motors are widely used from home to industrial applications. Speed of induction motor plays important role, so to control the speed of induction motor various techniques are adopted and one of these techniques is V/F control, which is adopted in this paper. This technique helps to control the speed in open control system in RPM. Moreover, Control is designed in LabVIEW, it is quite helpful to develop the circuit graphically and code is automatically written in the background to run on Field Programmable Gate Array (FPGA). The aim of this research is to study the impacts on diverse parameters during speed control of three phase induction machine with manipulation of GPIC. Solar technology is used as input source to drive the General-Purpose Inverter Controller (GPIC). Apart of this, impacts of modulation index and carrier frequency influencing the active, reactive and apparent power, temperature and power quality and current overshoot is analysed. MATLAB/Simulink and LabVIEW tools are used for simulation and results along with GPIC, Induction motor and solar panel as hardware.

scholarly journals Evaluation of Debris Flows for Flood Plain Estimation in a Small Ungauged Tropical Watershed for Hurricane Otto

Hydrology ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 122
Author(s):  
Sebastián Fallas Salazar ◽  
Alejandra M. Rojas González
Keyword(s):  
Debris Flows ◽  
Flood Plain ◽  
Rain Gauge ◽  
Economic Losses ◽  
Clean Water ◽  
Newtonian Flows ◽  
Bias Factor ◽  
Input Source ◽  
Debris Flood ◽  
Tropical Watershed

The variability of climate, increase in population, and lack of territorial plans in Costa Rica have caused intense disasters with human and economic losses. In 2016, Hurricane Otto hit the country’s northern area, leaving substantial damages, including landslides, debris flows, and flooding. The present study evaluated different scenarios to estimate flooded areas for Newtonian (clean water), and non-Newtonian flows with volumetric sediment concentrations (Cv) of 0.3, 0.45, 0.55, and 0.65 using Hydro-Estimator (HE), rain gauge station, and the 100-year return period event. HEC–HMS modeled the rainfall products, and FLO-2D modeled the hydrographs and Cv combinations. The simulation results were evaluated with continuous statistics, contingency table, Nash Sutcliffe Efficiency, measure of fit (F), and mean absolute differences (E) in the floodplains. Flow depths, velocities, and hazard intensities were obtained in the floodplain. The debris flood was validated with field data and classified with a Cv of 0.45, presenting lower MAE and RMSE. Results indicated no significant differences in flood depths between hydrological scenarios with clean-water simulations with a difference of 8.38% in the peak flow. The flood plain generated with HE rainfall and clear-water condition presented similar results compared to the rain gauge input source. Additionally, hydraulic results with HE and Cv of 0.45 presented E and F values similar to the simulation of Cv of 0.3, demonstrating that the HE bias did not influence the determination of the floodplain depth and extent. A mean bias factor can be applied to a sub-daily temporal resolution to enhance HE rain rate quantifications and floodplain determination.

Switched capacitor based single DC source boost multilevel inverter (S2-MLI) featuring isolation based soft charging with minimum device count

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tamiru Debela ◽  
Jiwanjot Singh
Keyword(s):  
Pulse Width Modulation ◽  
Multilevel Inverter ◽  
Superior Performance ◽  
Inrush Current ◽  
Switched Capacitor ◽  
Multilevel Inverters ◽  
Current Voltage ◽  
Power Switches ◽  
Input Source ◽  
Interest In Research

Abstract Multilevel inverters (MLIs) have formed a new wave of interest in research and industry. Switched capacitor-based multilevel inverters are used to avoid the need for multiple separated DC sources compared to cascaded MLIs. However, the inclusion of several capacitors creates problems such as high inrush current, voltage imbalance. To avoid these drawbacks, this paper proposes an isolation-based scheme by using a flyback converter in the switched capacitor multilevel inverter. Further, the overall topology provides step-up AC voltage across the load from a single DC source with fewer power switches. To generate a step-up five-level voltage across the load, switched capacitor-based multilevel inverter needs six power switches and only one capacitor. To get the appropriate switching operation to generate the NL-levels, phase disposition pulse width modulation (PD-PWM) has been developed. The extended nine-level S 2 -MLI is also discussed in this paper under different conditions as change in input source voltage and dynamic load change. Moreover, to prove the superior performance of switched-capacitor single DC source multilevel inverter (S2-MLI), comparative analysis with existing single DC source MLI has been performed. The effectiveness and feasibility of the proposed topology are tested with varieties of loads by simulation using Matlab/Simulink. To validate the simulation results, hardware implementation has been done of five-level S2-MLI considering resistive and motor load by using DSpace 1103 controller.

Nerve Impulse Patterns And Reflex Control in the Motor System of The Crayfish Claw

1965 ◽  
Vol 43 (2) ◽  
pp. 193-210
Author(s):  
D. M. WILSON ◽  
W. J. DAVIS
Keyword(s):  
Motor Neurons ◽  
Nerve Impulse ◽  
Apparent Lack ◽  
High Frequencies ◽  
Excitatory State ◽  
Input Source ◽  
Motor Neuron Pool ◽  
Frequency Changes ◽  
Positive Correlations ◽  
Interval Lengths

1. The opener muscle of the crayfish claw receives, under nearly natural conditions, a train of excitatory nerve impulses which may show a temporal patterning to which the muscle is specially sensitive. Especially at high frequencies the impulse train contains doublets which form a separate class in the interval distribution. Their appearance at high frequencies gives rise to an increase in the coefficient of variation of interval lengths. 2. Excitatory and inhibitory motor neurons to the same opener muscle seem to be part of the same commonly excited motor neuron pool. Frequency changes in the two axons generally show positive correlations. For most inputs and for ‘spontaneous’ central drive the excitor has the lowest threshold and shortest latency, and it gives the earliest indication of changes of excitatory state. 3. Proprioceptive input from the claw may excite both motor neurons, but generally the inhibitory one gives the earlier, bigger response. The peripheral inhibition completes a negative feedback loop. 4. Inhibitory frequencies plotted against concurrent excitatory frequencies give points falling into two groups with different slopes dependent upon input source. For general body inputs the slope is less than one and for proprioceptive claw input it is much more than one. This divergence leads to greater effectiveness of either excitation or inhibition as overall level of output increases, with a good separation of antagonistic functions in spite of the apparent lack of reciprocal interaction.

Data Hiding for Stereo Audio Signals

2013 ◽  
pp. 104-128
Author(s):  
Kazuhiro Kondo
Keyword(s):  
Data Hiding ◽  
Audio Signal ◽  
Audio Coding ◽  
Original Signal ◽  
Audio Signals ◽  
Audio Quality ◽  
Input Source ◽  
Rate Conversion ◽  
Fixed Delay

This chapter proposes two data-hiding algorithms for stereo audio signals. The first algorithm embeds data into a stereo audio signal by adding data-dependent mutual delays to the host stereo audio signal. The second algorithm adds fixed delay echoes with polarities that are data dependent and amplitudes that are adjusted such that the interchannel correlation matches the original signal. The robustness and the quality of the data-embedded audio will be given and compared for both algorithms. Both algorithms were shown to be fairly robust against common distortions, such as added noise, audio coding, and sample rate conversion. The embedded audio quality was shown to be “fair” to “good” for the first algorithm and “good” to “excellent” for the second algorithm, depending on the input source.

scholarly journals Fast Humidity Sensors for Harsh Environment

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 988
Author(s):  
Anton Buchberger ◽  
Anna Coclite ◽  
Alexander Bergmann
Keyword(s):  
Abrupt Change ◽  
Chemical Vapor ◽  
Harsh Environment ◽  
Humidity Sensors ◽  
Thickness Change ◽  
Sensor Layer ◽  
Active Sensor ◽  
Initiated Chemical Vapor Deposition ◽  
Input Source ◽  
Light Input

With the application of a recently developed deposition method called initiated chemical vapor deposition (iCVD), remarkably fast responsive hydrogel thin films in the order of a few hundred nanometers were created. When in contact with humid air, the hydrogel layer extends its thickness manifold, which can be detected. The verification of the thickness change was realized interferometrically with a laser and a white light input source in two different implementations. The setup was designed without electric components in the vicinity of the active sensor layer and is therefore applicable in harsh and explosive environment. The achieved response time for an abrupt change of the humidity τ63 ≤ 2.5 s is about three times lower compared to one of the fastest commercially available sensors on the market.

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