Showing papers on "Filter (video) published in 2014"

The Labeled Multi-Bernoulli Filter

Abstract: This paper proposes a generalization of the multi- Bernoulli filter called the labeled multi-Bernoulli filter that outputs target tracks. Moreover, the labeled multi-Bernoulli filter does not exhibit a cardinality bias due to a more accurate update approximation compared to the multi-Bernoulli filter by exploiting the conjugate prior form for labeled Random Finite Sets. The proposed filter can be interpreted as an efficient approximation of the $\delta$ -Generalized Labeled Multi-Bernoulli filter. It inherits the advantages of the multi-Bernoulli filter in regards to particle implementation and state estimation. It also inherits advantages of the $\delta$ -Generalized Labeled Multi-Bernoulli filter in that it outputs (labeled) target tracks and achieves better performance.

$LCL$ Filter Design and Performance Analysis for Grid-Interconnected Systems

Abstract: The use of power converters is very important in maximizing the power transfer from renewable energy sources such as wind, solar, or even a hydrogen-based fuel cell to the utility grid An LCL filter is often used to interconnect an inverter to the utility grid in order to filter the harmonics produced by the inverter Although there is an extensive amount of literature available describing LCL filters, there has been a gap in providing a systematic design methodology Furthermore, there has been a lack of a state-space mathematical modeling approach that considers practical cases of delta- and wye-connected capacitors showing their effects on possible grounding alternatives This paper describes a design methodology of an LCL filter for grid-interconnected inverters along with a comprehensive study of how to mitigate harmonics The procedures and techniques described in this paper may be used in small-scale renewable energy conversion systems and may be also retrofitted for medium- and large-scale grid-connected systems

Rolling Guidance Filter

Abstract: Images contain many levels of important structures and edges. Compared to masses of research to make filters edge preserving, finding scale-aware local operations was seldom addressed in a practical way, albeit similarly vital in image processing and computer vision. We propose a new framework to filter images with the complete control of detail smoothing under a scale measure. It is based on a rolling guidance implemented in an iterative manner that converges quickly. Our method is simple in implementation, easy to understand, fully extensible to accommodate various data operations, and fast to produce results. Our implementation achieves realtime performance and produces artifact-free results in separating different scale structures. This filter also introduces several inspiring properties different from previous edge-preserving ones.

Moving Average Filter Based Phase-Locked Loops: Performance Analysis and Design Guidelines

Abstract: The phase-locked loops (PLLs) are probably the most widely used synchronization technique in grid-connected applications. The main challenge that is associated with the PLLs is how to precisely and fast estimate the phase and frequency, when the grid voltage is unbalanced and/or distorted. To overcome this challenge, incorporating moving average filter(s) (MAF) into the PLL structure has been proposed in some recent literature. An MAF is a linear-phase finite-impulse-response filter, which can act as an ideal low-pass filter, if certain conditions hold. The main aim of this paper is to present the control design guidelines for a typical MAF-based PLL. The paper starts with the general description of MAFs. The main challenge associated with using the MAFs is then explained, and its possible solutions are discussed. The paper then proceeds with a brief overview of the different MAF-based PLLs. In each case, the PLL block diagram description is shown, the advantages and limitations are briefly discussed, and the tuning approach (if available) is evaluated. The paper then presents two systematic methods to design the control parameters of a typical MAF-based PLL: one for the case of using a proportional-integral (PI) type loop filter (LF) in the PLL, and the other for the case of using a proportional-integral-derivative (PID) type LF. Finally, the paper compares the performance of a well-tuned MAF-based PLL when using the PI-type LF with the results of using the PID-type LF, which provides useful insights into their capabilities and limitations.

Automatic data collection apparatus and method

Abstract: Machine-readable symbol readers and/or scan engines may subtractively impose an aiming pattern on an illumination field produced by a source of light or illumination. An optical component with a mask or filter are interposed in an optical path extending outwardly from the source of light or illumination. The mask or filter may have a defined shape or configuration to subtractively produce an aiming pattern with a desired shape or configuration. The mask or filter may, or may not, be wavelength selective or spectral. A wavelength selective mask or filter may produce an aiming pattern of a defined color, different from a color of an illumination field. Such may eliminate the need for a separate, distinct source of light or illumination for an aiming beam subsystem. The described structures and methods may reduce size, reduce parts count, and/or simplify manufacture.

Multispectral Filter Arrays: Recent Advances and Practical Implementation

Abstract: Thanks to some technical progress in interferencefilter design based on different technologies, we can finally successfully implement the concept of multispectral filter array-based sensors. This article provides the relevant state-of-the-art for multispectral imaging systems and presents the characteristics of the elements of our multispectral sensor as a case study. The spectral characteristics are based on two different spatial arrangements that distribute eight different bandpass filters in the visible and near-infrared area of the spectrum. We demonstrate that the system is viable and evaluate its performance through sensor spectral simulation.

Filter-Free Image Sensor Pixels Comprising Silicon Nanowires with Selective Color Absorption

Abstract: The organic dye filters of conventional color image sensors achieve the red/green/blue response needed for color imaging, but have disadvantages related to durability, low absorption coefficient, and fabrication complexity. Here, we report a new paradigm for color imaging based on all-silicon nanowire devices and no filters. We fabricate pixels consisting of vertical silicon nanowires with integrated photodetectors, demonstrate that their spectral sensitivities are governed by nanowire radius, and perform color imaging. Our approach is conceptually different from filter-based methods, as absorbed light is converted to photocurrent, ultimately presenting the opportunity for very high photon efficiency.

Bilateral texture filtering

Abstract: This paper presents a novel structure-preserving image decomposition operator called bilateral texture filter. As a simple modification of the original bilateral filter [Tomasi and Manduchi 1998], it performs local patch-based analysis of texture features and incorporates its results into the range filter kernel. The central idea to ensure proper texture/structure separation is based on patch shift that captures the texture information from the most representative texture patch clear of prominent structure edges. Our method outperforms the original bilateral filter in removing texture while preserving main image structures, at the cost of some added computation. It inherits well-known advantages of the bilateral filter, such as simplicity, local nature, ease of implementation, scalability, and adaptability to other application scenarios.

Model Predictive Approach for a Simple and Effective Load Voltage Control of Four-Leg Inverter With an Output $LC$ Filter

Abstract: This paper presents a finite control set model predictive strategy and its application to the load voltage control of two-level four-leg inverters. The proposed approach uses the novel discrete-time model of the inverter and output LC filter in order to predict the variables to be controlled. These predictions are carried out for the 16 switching states of the inverter and are evaluated using a cost function. The switching state that forces the load voltages to be closest to their respective references is chosen and applied to the inverter. The behavior of the predictive controller has been investigated, and the changes to both inductive and capacitive filter parameters have been considered. In order to improve the reliability of the fourth leg as well as the overall inverter efficiency, a solution is proposed, which combines hardware and software reconfigurations. The feasibility of the proposed method is verified through simulation and experimental results considering single-/three-phase, balanced/unbalanced, and linear/nonlinear loads.

Minimal Invasive Equivalent Grid Impedance Estimation in Inductive–Resistive Power Networks Using Extended Kalman Filter

Abstract: Real-time estimation of the equivalent grid impedance and the equivalent grid voltage seen from a power converter connected to the public electric distribution network by means of extended Kalman filter is addressed. The theoretical background of the extended Kalman filter used for equivalent grid impedance estimation is introduced. Practical aspects like the use of the filter in an environment with highly distorted voltage waveforms, the tuning of the noise covariance matrices, and the implementation on a laboratory system are discussed. The theoretical analysis is verified on a 22-kW test-bench where a grid impedance emulator is used to simulate grid impedance steps in the laboratory environment. The proposed extended Kalman filter is designed to utilize the noise that is already present at the connection point of the power converter to overcome the need of active disturbance injection to estimate the equivalent grid impedance. Thus, electrical equipment connected close to the grid-connected converter is only affected marginally by the equivalent grid impedance estimation technique.

Apparatus and method for protecting communication pattern of network traffic

Abstract: An apparatus for protecting traffic trend in a network of a control system using artificial communication is provided. In accordance with an embodiment, the apparatus includes a communication terminal device installed in a network and configured to create and filter artificial communication. A communication server device determines whether to create artificial communication at a current time in the communication terminal device, requests a transmitting side-communication terminal device to create artificial communication, and requests a receiving side-communication terminal device to filter the artificial communication.

A Novel Design and Optimization Method of an $LCL$ Filter for a Shunt Active Power Filter

Abstract: Compared with the L filter, the LCL filter is more suitable for high-power low-switching-frequency applications due to its better attenuation characteristics on high frequencies. However, the parameter design for the LCL filter is more complex since both the inhibiting effect of the high-frequency harmonic current and the influence to the controller response performance of the converter should be considered. In this paper, the model of the LCL filter and the design criteria of the LCL filter for a shunt active power filter (SAPF) are analyzed in the beginning. Then, the impacts of all parameters of the LCL filter on SAPF are intuitively drawn on a graph by theoretical derivation. Finally, a novel parameter design and optimization method for the LCL filter is proposed. The validity and effectiveness of the proposed method are proved by simulated and experimental results of a single-phase SAPF prototype at the end of this paper.

A Robust Passive Damping Method for LLCL-Filter-Based Grid-Tied Inverters to Minimize the Effect of Grid Harmonic Voltages

Abstract: In order to minimize the effect of the grid harmonic voltages, harmonic compensation is usually adopted for a grid-tied inverter. However, a large variation of the grid inductance challenges the system stability in case a high-order passive filter is used to connect an inverter to the grid. Although in theory, an adaptive controller can solve this problem, but in such a case the grid inductance may need to be detected online, which will complicate the control system. This paper investigates the relationship between the maximum gain of the controller that still keeps the system stable and the Q-factor for a grid-tied inverter with an RL series or an RC parallel damped high-order power filter. Then, a robust passive damping method for LLCL-filter-based grid-tied inverters is proposed, which effectively can suppress the possible resonances even if the grid inductance varies in a wide range. Simulation and experimental results are in good agreement with the theoretical analysis.

Real-time control of shunt active power filter under distorted grid voltage and unbalanced load condition using self-tuning filter

Abstract: In this paper, an alternative control method is proposed to improve the harmonic suppression efficiency of the active power filter in a distorted and an unbalanced power system to compensate for the perturbations caused by the unbalanced non-linear loads. The proposed method uses a self-tuning filter (STF) to process the grid voltage in order to provide a uniform reference voltage to obtain the correct angular position of the phase locked loop. Moreover, the required compensation currents are obtained by implementing another STF in the transformed set of currents in order to separate the fundamental and the harmonic currents. This allows the calculation of a precise reference current for the unbalanced, the non-linear and the variable load conditions. The proposed control method gives an adequate compensating current reference even for a non-ideal voltage and unbalanced current conditions. The real-time control of the filter under the distorted and the unbalanced power system is developed in an RT-LAB real-time platform. The results obtained in the software-in-the-loop configuration are presented to verify the effectiveness of the proposed control technique.

Methods and systems for analyzing entity performance

Abstract: Systems and methods are provided for analyzing entity performance. In one implementation, a method is provided that includes receiving a request with one or more filter selections and accessing a data structure comprising a plurality of categories of information showing interactions associated with multiple entities. The method also comprises identifying a set of categories of the plurality of categories within the data structure based on the one or more filter selections. The method further comprises processing the information of the identified categories to analyze a performance of one or more entities of the multiple entities in accordance with the one or more filter selections and providing the processed information to display the performance of the one or more entities on a user interface.

Positive/negative lossy/lossless grounded inductance simulators employing single VDCC and only two passive elements

Abstract: Actively simulated grounded inductors have been used in several applications ranging from filter to oscillator design as well as cancellation of parasitic inductances. In this paper, new grounded inductance simulators employing only one voltage differencing current conveyor (VDCC) and two passive components are proposed. Two new topologies for realizing positive and negative lossless inductances and four different topologies for realizing lossy inductances are proposed. The aim of this paper is to present new inductance simulators using the minimum number of active and passive components. The proposed inductance simulators can be tuned electronically by changing the biasing current of the VDCC. Moreover, the circuits do not require any conditions of component matching. Finally, using one of the proposed inductance simulators a third-order high-pass filter is constructed. The performance of the proposed filter is verified and simulated by using SPICE.

Video based localization for Bertha

Abstract: In August 2013, the modified Mercedes-Benz SClass S500 Intelligent Drive (“Bertha”) completed the historic Bertha-Benz-Memorial-Route fully autonomously. The self-driving 103 km journey passed through urban and rural areas. The system used detailed geometric maps to supplement its online perception systems. A map based approach is only feasible if a precise, map relative localization is provided. The purpose of this paper is to give a survey on this corner stone of the system architecture. Two supplementary vision based localization methods have been developed. One of them is based on the detection of lane markings and similar road elements, the other exploits descriptors for point shaped features. A final filter step combines both estimates while handling out-of-sequence measurements correctly.

The Path Inference Filter: Model-Based Low-Latency Map Matching of Probe Vehicle Data

Abstract: We consider the problem of reconstructing vehicle trajectories from sparse sequences of GPS points, for which the sampling interval is between 1 s and 2 min. We introduce a new class of algorithms, which are altogether called the path inference filter (PIF), that maps GPS data in real time, for a variety of tradeoffs and scenarios and with a high throughput. Numerous prior approaches in map matching can be shown to be special cases of the PIF presented in this paper. We present an efficient procedure for automatically training the filter on new data, with or without ground-truth observations. The framework is evaluated on a large San Francisco taxi data set and is shown to improve upon the current state of the art. This filter also provides insights about driving patterns of drivers. The PIF has been deployed at an industrial scale inside the Mobile Millennium traffic information system, and is used to map fleets of data in San Francisco and Sacramento, CA, USA; Stockholm, Sweden; and Porto, Portugal.

An Improved Hybrid DSTATCOM Topology to Compensate Reactive and Nonlinear Loads

Abstract: This paper proposes an improved hybrid distribution static compensator (DSTATCOM) topology to address some practical issues such as power rating, filter size, compensation performance, and power loss. An LCL filter has been used at the front end of a voltage source inverter (VSI), which provides better switching harmonics elimination while using much smaller value of an inductor as compared with the traditional L filter. A capacitor is used in series with an LCL filter to reduce the dc-link voltage of the DSTATCOM. This consequently reduces the power rating of the VSI. With reduced dc-link voltage, the voltage across the shunt capacitor of the LCL filter will be also less. It will reduce the power losses in the damping resistor as compared with the traditional LCL filter with passive damping. Therefore, the proposed DSTATCOM topology will have reduced weight, cost, rating, and size with improved efficiency and current compensation capability compared with the traditional topology. A systematic procedure to design the components of the passive filter has been presented. The effectiveness of the proposed DSTATCOM topology over traditional topologies is validated through both simulation and experimental studies.

Data-Dependent Fingerprints for Wireless Device Authentication

Abstract: : While authenticating wireless radios based on the unique imperfections in their transmitted waveform has become a topic of some interest, such fingerprinting techniques are vulnerable to an attacker who can listen to a radio's transmission and later mimic the transmission using a sophisticated arbitrary waveform generator. However, this type of vulnerability can be reduced if the authentication is accomplished using a random selection from a long list of possible challenge-response pairs and if the node requesting network access has a fingerprint that changes with each valid response. This work provides a first study of such a concept using a tunable filter, used during the authentication exchange, whose tuning voltages are determined from the response data. The work uses simulations and measurements to demonstrate the effectiveness of estimating the distortion function introduced by the tunable filter and using it to identify the device. Results show that the technique can achieve near perfect discrimination between devices and can reject an attacker with very high probability.

Sound stage controller for a near-field speaker-based audio system

Abstract: Signals in an automobile audio system having at least two near-field speakers located close to an intended position of a listener's head are adjusted such that in a first mode, audio signals are distributed to the near-field speakers according to a first filter that causes the listener to perceive a wide soundstage, and in a second mode, the audio signals are distributed to the near-field speakers according to a second filter that causes the listener to perceive a narrow soundstage. A user input of a variable value is received and, in response, distribution of the audio signals is transitioned from the first mode to the second mode, the extent of the transition being variable based on the value of the user input.

Event triggered robust filter design for discrete-time systems

Abstract: This study introduces a general event triggered framework of state estimation for discrete-time systems with parameter uncertainties residing in a polytope. A robust filter is designed to ensure the l2 stability from disturbance to the estimation error and to minimise the l2 gain subject to both packet rate and size constraints. The number of data transmission and the data size are reduced by the utilisation of an event detector and a logarithmic quantiser, respectively. The event detector compares the current output measurement with the last transmitted measurement: if the difference is beyond a prescribed percentage of the current measurement, then the current measurement is transmitted to the quantiser. The quantiser encodes the measurement before sending to the filter via a digital communication channel. Conditions for filter design are found using polynomially parameter-dependent Lyapunov functions, which generalise the results using quadratic and linearly parameter-dependent Lyapunov functions. The usefulness of the techniques is demonstrated with an illustrative example.

Asynchronous binaural spatial audition sensor with 2 × 64 × 4 channel output.

Abstract: This paper proposes an integrated event-based binaural silicon cochlea system aimed at efficient spatial audition and auditory scene analysis The cochlea chip has a matched pair of digitally-calibrated 64-stage cascaded analog second-order filter banks with 512 pulse-frequency modulated (PFM) address-event representation (AER) outputs The quality factors (Qs) of channels are individually adjusted by local DACs The 2P4M 035 um CMOS chip consumes an average power of 14 mW including its integrated microphone preamplifiers and biasing circuits Typical speech data rates are 10 k to 100 k events per second (eps) with peak output rates of 10 Meps The event timing jitter is 2 us for a 250 mVpp input It is shown that the computational cost of an event-driven source localization application can be up to 40 times lower when compared to a conventional cross-correlation approach

Fault Detection for T–S Fuzzy Systems With Unknown Membership Functions

Abstract: This paper is concerned with the fault detection (FD) problem for Takagi-Sugeno (T-S) fuzzy systems with unknown membership functions. If the membership functions are unknown, the linear FD filter designs with fixed gains have been considered in the literature. To reduce the conservatism of the existing results, a switching mechanism that depends on the lower and upper bounds of the unknown membership functions is provided to construct an FD filter with varying gains. It is shown that the switching-type FD filter with varying gains can achieve a better FD performance than the linear FD filter with fixed gains. In addition, based on some time-domain inequalities, a novel weighting matrix design approach is introduced to transform the fault sensitivity specification into an H∞ constraint. Finally, two examples are given to show the advantages of the proposed FD method.

Maximally Flat Negative Group-Delay Circuit: A Microwave Transversal Filter Approach

Abstract: A comprehensive method to synthesize negative group delay (NGD) in the microwave regime with a maximally flat response is proposed in this paper. This method is based on transversal-filter topologies; it will be shown that by choosing proper coupling coefficients of each tap of a transversal filter, we can realize NGDs with maximally flat characteristics at the output of the transversal filter. The desired coefficients to realize maximally flat NGDs with various amount of group delay are analytically derived and tabulated in this paper. Furthermore, the results are verified experimentally through microwave transversal-filter approaches in both passive and active ways using multi-section asymmetric directional couplers and distributed amplifiers.