Scheduling Algorithms Based on Weakly Hard Real-Time Constraints
TU Gang (涂刚); YANG FuMin (阳富民); LU YanSheng (卢炎生)
2003-01-01
The problem of scheduling weakly hard real-time tasks is addressed in this paper.The paper first analyzes the characters ofμ-pattern and weakly hard real-time constraints, then,presents two scheduling algorithms, Meet Any Algorithm and Meet Row Algorithm, for weakly hard real-time systems. Different from traditional algorithms used to guarantee deadlines, Meet Any Algorithm and Meet Row Algorithm can guarantee both deadlines and constraints. Meet Any Algorithm and Meet Row Algorithm try to find out the probabilities of tasks breaking constraints and increase task's priority in advance, but not till the last moment. Simulation results show that these two algorithms are better than other scheduling algorithms dealing with constraints and can largely decrease worst-case computation time of real-time tasks.
Feature Selection Criteria for Real Time EKF-SLAM Algorithm
Fernando Auat Cheein
2010-02-01
Full Text Available This paper presents a seletion procedure for environmet features for the correction stage of a SLAM (Simultaneous Localization and Mapping algorithm based on an Extended Kalman Filter (EKF. This approach decreases the computational time of the correction stage which allows for real and constant-time implementations of the SLAM. The selection procedure consists in chosing the features the SLAM system state covariance is more sensible to. The entire system is implemented on a mobile robot equipped with a range sensor laser. The features extracted from the environment correspond to lines and corners. Experimental results of the real time SLAM algorithm and an analysis of the processing-time consumed by the SLAM with the feature selection procedure proposed are shown. A comparison between the feature selection approach proposed and the classical sequential EKF-SLAM along with an entropy feature selection approach is also performed.
A new real-time tsunami detection algorithm
Chierici, Francesco; Embriaco, Davide; Pignagnoli, Luca
2017-01-01
Real-time tsunami detection algorithms play a key role in any Tsunami Early Warning System. We have developed a new algorithm for tsunami detection based on the real-time tide removal and real-time band-pass filtering of seabed pressure recordings. The algorithm greatly increases the tsunami detection probability, shortens the detection delay and enhances detection reliability with respect to the most widely used tsunami detection algorithm, while containing the computational cost. The algorithm is designed to be used also in autonomous early warning systems with a set of input parameters and procedures which can be reconfigured in real time. We have also developed a methodology based on Monte Carlo simulations to test the tsunami detection algorithms. The algorithm performance is estimated by defining and evaluating statistical parameters, namely the detection probability, the detection delay, which are functions of the tsunami amplitude and wavelength, and the occurring rate of false alarms. Pressure data sets acquired by Bottom Pressure Recorders in different locations and environmental conditions have been used in order to consider real working scenarios in the test. We also present an application of the algorithm to the tsunami event which occurred at Haida Gwaii on 28 October 2012 using data recorded by the Bullseye underwater node of Ocean Networks Canada. The algorithm successfully ran for test purpose in year-long missions onboard abyssal observatories, deployed in the Gulf of Cadiz and in the Western Ionian Sea.
A New Scheduling Algorithms For Real Time Tasks
Yaashuwanth, C
2009-01-01
The main objective of this paper is to develop the two different ways in which round robin architecture is modified and made suitable to be implemented in real time and embedded systems. The scheduling algorithm plays a significant role in the design of real time embedded systems. Simple round robin architecture is not efficient to be implemented in embedded systems because of higher context switch rate, larger waiting time and larger response time. Missing of deadlines will degrade the system performance in soft real time systems. The main objective of this paper is to develop the scheduling algorithm which removes the drawbacks in simple round robin architecture. A comparison with round robin architecture to the proposed architectures has been made. It is observed that the proposed architectures solves the problems encountered in round robin architecture in soft real time by decreasing the number of context switches waiting time and response time thereby increasing the system throughput.
Enhanced Utility Accrual Scheduling Algorithms for Adaptive Real Time System
Idawaty Ahmad
2009-01-01
Full Text Available Problem statement: This study proposed two utility accrual real time scheduling algorithms named as Preemptive Utility Accrual Scheduling (PUAS and Non-preemptive Utility Accrual Scheduling (NUAS algorithms. These algorithms addressed the unnecessary abortion problem that was identified in the existing algorithm known as General Utility Scheduling (GUS. It is observed that GUS is inefficient for independent task model because it simply aborts any task that currently executing a resource with lower utility when a new task with higher utility requests the resource. The scheduling optimality criteria are based on maximizing accrued utility accumulated from execution of all tasks in the system. These criteria are named as Utility Accrual (UA. The UA scheduling algorithms are design for adaptive real time system environment where deadline misses are tolerable and do not have great consequences to the system. Approach: We eliminated the scheduling decision to abort a task in GUS and proposed to preempt a task instead of being aborted if the task is preemptive able. We compared the performances of these algorithms by using discrete event simulation. Results: The proposed PUAS algorithm achieved the highest accrued utility for the entire load range. This is followed by the NUAS and GUS algorithms. Conclusion: Simulation results revealed that the proposed algorithms were more efficient than the existing algorithm, producing with higher accrued utility ratio and less abortion ratio making it more suitable and efficient for real time application domain.
A real time vehicles detection algorithm for vision based sensors
Płaczek, Bartłomiej
2011-01-01
A vehicle detection plays an important role in the traffic control at signalised intersections. This paper introduces a vision-based algorithm for vehicles presence recognition in detection zones. The algorithm uses linguistic variables to evaluate local attributes of an input image. The image attributes are categorised as vehicle, background or unknown features. Experimental results on complex traffic scenes show that the proposed algorithm is effective for a real-time vehicles detection.
REAL TIME FACE RECOGNITION USING ADABOOST IMPROVED FAST PCA ALGORITHM
K. Susheel Kumar
2011-08-01
Full Text Available This paper presents an automated system for human face recognition in a real time background world fora large homemade dataset of persons face. The task is very difficult as the real time backgroundsubtraction in an image is still a challenge. Addition to this there is a huge variation in human face imagein terms of size, pose and expression. The system proposed collapses most of this variance. To detect realtime human face AdaBoost with Haar cascade is used and a simple fast PCA and LDA is used torecognize the faces detected. The matched face is then used to mark attendance in the laboratory, in ourcase. This biometric system is a real time attendance system based on the human face recognition with asimple and fast algorithms and gaining a high accuracy rate..
A distributed scheduling algorithm for heterogeneous real-time systems
Zeineldine, Osman; El-Toweissy, Mohamed; Mukkamala, Ravi
1991-01-01
Much of the previous work on load balancing and scheduling in distributed environments was concerned with homogeneous systems and homogeneous loads. Several of the results indicated that random policies are as effective as other more complex load allocation policies. The effects of heterogeneity on scheduling algorithms for hard real time systems is examined. A distributed scheduler specifically to handle heterogeneities in both nodes and node traffic is proposed. The performance of the algorithm is measured in terms of the percentage of jobs discarded. While a random task allocation is very sensitive to heterogeneities, the algorithm is shown to be robust to such non-uniformities in system components and load.
Real-time extended-depth DIC microscopy
Beckers, Ingeborg E.; Cormack, Robert H.; Cogswell, Carol J.
2010-02-01
Real-time visualization of live-cell dynamic processes has been realized in differential interference contrast (DIC) microscopy, with an extended-depth-of-focus (EDF) increase of about one order of magnitude. In addition, the diffraction-limited lateral resolution of the microscope is preserved. Experimentally, a custom-designed waveplate inserted in the optical path of a microscope causes feature information, from within the entire 3D specimen volume, to be uniformly encoded into a single CCD image in a way that, after processing, defocus blur artifacts are removed. The result is that extended-depth feature information can be visualized at video rates during live-cell dynamics investigations because there is no longer the need to acquire multi-focus image stacks at each time point. Retrieving the encoded extended-depth information requires specialized digital image processing techniques. This work concentrates on digital filter design for the reconstruction of the waveplate-encoded images. As a measure of filter quality, the signal-to-noise ratio (SNR), the modulation transfer function and the least mean square values are evaluated. Obtaining a high SNR and a lateral resolution comparable to those in conventional single-focus-plane microscopy images at the same time is a challenging goal in EDF microscopy. Filters are created in the frequency domain on the basis of the measured waveplate-encoded point spread functions. Results show that it is possible to produce video-rate, extended-depth-offocus images that have low noise levels and diffraction-limited resolution. This is illustrated by movies of fluorescent beads and of cytoplasmic streaming in live stamen hair cells from the spiderwort plant, Tradescantia, using extendeddepth DIC microscopy.
Admission Control Algorithm for Guaranteeing Real-Time Anycast Flow
Weijia Jia; Zhang Chuanlin
2002-01-01
In this paper, we study admission control algorithm for anycast flow with real-time constraints. With the given time requirement, when the result of this algorithm give succeed information, we find route for the anycast flow requesting. Therefore, what we need to do is testing if the corresponding path rj has enough bandwidth for coming anycast flow requirement at source S with end-to-end deadline D. This admission control is scalable in terms of the number of flows can be admitted through local information of the routes.
A Novel Real Time Motion Detection Algorithm For Videos
M. Nagaraju
2013-11-01
Full Text Available Real-time detection of moving objects is vital for video surveillance. Background subtraction serves as a basic method typically used to segment the moving objects in image sequences taken from a camera. Some existing algorithms cannot fine-tune changing circumstances and they need manual calibration in relation to specification of parameters or some hypotheses for dynamic changing background. An adaptive motion segmentation and detection strategy is developed by using motion variation and chromatic characteristics, which eliminates undesired corruption of the background model and it doesn't look on the adaptation coefficient. In this particular proposed work, a novel real-time motion detection algorithm is proposed for dynamic changing background features. The algorithm integrates the temporal differencing along with optical flow method, double background filtering method and morphological processing techniques to achieve better detection performance. Temporal differencing is designed to detect initial motion areas for the optical-flow calculation to produce real-time and accurate object motion vectors detection. The double background filtering method is obtain and keep a reliable background image to handle variations on environmental changing conditions that is designed to get rid of the background interference and separate the moving objects from it. The morphological processing methods are adopted and mixed with the double background filtering to obtain improved results. The most attractive benefit for this algorithm is that the algorithm does not require to figure out the background model from hundreds of images and can handle quick image variations without prior understanding of the object size and shape.
Visualizing Concurrency Control Algorithms for Real-Time Database Systems
Olusegun Folorunso
2008-11-01
Full Text Available This paper describes an approach to visualizing concurrency control (CC algorithms for real-time database systems (RTDBs. This approach is based on the principle of software visualization, which has been applied in related fields. The Model-View-controller (MVC architecture is used to alleviate the black box syndrome associated with the study of algorithm behaviour for RTDBs Concurrency Controls. We propose a Visualization "exploratory" tool that assists the RTDBS designer in understanding the actual behaviour of the concurrency control algorithms of choice and also in evaluating the performance quality of the algorithm. We demonstrate the feasibility of our approach using an optimistic concurrency control model as our case study. The developed tool substantiates the earlier simulation-based performance studies by exposing spikes at some points when visualized dynamically that are not observed using usual static graphs. Eventually this tool helps solve the problem of contradictory assumptions of CC in RTDBs.
Real Time Equilibrium Reconstruction Algorithm in EAST Tokamak
王华忠; 罗家融; 黄勤超
2004-01-01
The EAST (HT-7U) superconducting tokamak is a national project of China on fusion research, with a capability of long-pulse (～ 1000 s) operation. In order to realize a longduration steady-state operation of EAST, some significant capability of real-time control is required. It would be very crucial to obtain the current profile parameters and the plasma shapes in real time by a flexible control system. As those discharge parameters cannot be directly measured,so a current profile consistent with the magnetohydrodynamic equilibrium should be evaluated from external magnetic measurements, based on a linearized iterative least square method, which can meet the requirements of the measurements. The arithmetic that the EFIT (equilibrium fitting code) is used for reference will be given in this paper and the computational efforts are reduced by parametrizing the current profile linearly in terms of a number of physical parameters.In order to introduce this reconstruction algorithm clearly, the main hardware design will be listed also.
A Real-time Single Pulse Detection Algorithm for GPUs
Adámek, Karel
2016-01-01
The detection of non-repeating events in the radio spectrum has become an important area of study in radio astronomy over the last decade due to the discovery of fast radio bursts (FRBs). We have implemented a single pulse detection algorithm, for NVIDIA GPUs, which use boxcar filters of varying widths. Our code performs the calculation of standard deviation, matched filtering by using boxcar filters and thresholding based on the signal-to-noise ratio. We present our parallel implementation of our single pulse detection algorithm. Our GPU algorithm is approximately 17x faster than our current CPU OpenMP code (NVIDIA Titan XP vs Intel E5-2650v3). This code is part of the AstroAccelerate project which is a many-core accelerated time-domain signal processing code for radio astronomy. This work allows our AstroAccelerate code to perform a single pulse search on SKA-like data 4.3x faster than real-time.
Real-Time Flavor Tagging Algorithms in ATLAS
Hetherly, Jeffrey Wayne; The ATLAS collaboration; Zivkovic, Lidija
2015-01-01
In high-energy physics experiments, online selection is crucial to select interesting collisions from the large data volume. ATLAS b-jet triggers are designed to identify heavy-flavour content in real-time and provide the only option to efficiently record events with fully hadronic final states containing b-jets. In doing so, two different, but related, challenges are faced. The physics goal is to optimise as far as possible the rejection of light jets, while retaining a high efficiency on selecting b-jets and maintaining affordable trigger rates without raising jet energy thresholds. This results in a challenging computing task, as tracks and their corresponding vertices must be reconstructed and analysed for each jet above the desired threshold, regardless of the increasingly adverse pile-up conditions. We present an overview of the ATLAS strategy for online b-jet selection for the LHC Run 2, including the use of novel methods and sophisticated algorithms designed to face the above mentioned challenges. A f...
Extending the Real-Time Maude Semantics of Ptolemy to Hierarchical DE Models
Bae, Kyungmin; 10.4204/EPTCS.36.3
2010-01-01
This paper extends our Real-Time Maude formalization of the semantics of flat Ptolemy II discrete-event (DE) models to hierarchical models, including modal models. This is a challenging task that requires combining synchronous fixed-point computations with hierarchical structure. The synthesis of a Real-Time Maude verification model from a Ptolemy II DE model, and the formal verification of the synthesized model in Real-Time Maude, have been integrated into Ptolemy II, enabling a model-engineering process that combines the convenience of Ptolemy II DE modeling and simulation with formal verification in Real-Time Maude.
A Real-Time Structure of Attitude Algorithm for High Dynamic Bodies
Xingcheng Li
2017-01-01
Full Text Available To solve the real-time problem of attitude algorithm for high dynamic bodies, a real-time structure of attitude algorithm is developed by analyzing the conventional structure that has two stages, and a flow diagram of a real-time structure for a Matlab program is provided in detail. During the update of the attitude matrix, the real-time structure saves every element of attitude matrix in minor loop in real time and updates the next attitude matrix based on the previous matrix every subsample time. Thus, the real-time structure avoids lowering updating frequency, though the multisubsample algorithms are used. Simulation and analysis show that the real-time structure of attitude algorithm is better than the conventional structure due to short update time of attitude matrix and small drifting error, and it is more appropriate for high dynamic bodies.
Reconciling fault-tolerant distributed algorithms and real-time computing.
Moser, Heinrich; Schmid, Ulrich
We present generic transformations, which allow to translate classic fault-tolerant distributed algorithms and their correctness proofs into a real-time distributed computing model (and vice versa). Owing to the non-zero-time, non-preemptible state transitions employed in our real-time model, scheduling and queuing effects (which are inherently abstracted away in classic zero step-time models, sometimes leading to overly optimistic time complexity results) can be accurately modeled. Our results thus make fault-tolerant distributed algorithms amenable to a sound real-time analysis, without sacrificing the wealth of algorithms and correctness proofs established in classic distributed computing research. By means of an example, we demonstrate that real-time algorithms generated by transforming classic algorithms can be competitive even w.r.t. optimal real-time algorithms, despite their comparatively simple real-time analysis.
Hardware Algorithms For Tile-Based Real-Time Rendering
Crisu, D.
2012-01-01
In this dissertation, we present the GRAphics AcceLerator (GRAAL) framework for developing embedded tile-based rasterization hardware for mobile devices, meant to accelerate real-time 3-D graphics (OpenGL compliant) applications. The goal of the framework is a low-cost, low-power, high-performance
Hardware Algorithms For Tile-Based Real-Time Rendering
Crisu, D.
2012-01-01
In this dissertation, we present the GRAphics AcceLerator (GRAAL) framework for developing embedded tile-based rasterization hardware for mobile devices, meant to accelerate real-time 3-D graphics (OpenGL compliant) applications. The goal of the framework is a low-cost, low-power, high-performance d
Real-Time Extended Interface Automata for Software Testing Cases Generation
Shunkun Yang
2014-01-01
Full Text Available Testing and verification of the interface between software components are particularly important due to the large number of complex interactions, which requires the traditional modeling languages to overcome the existing shortcomings in the aspects of temporal information description and software testing input controlling. This paper presents the real-time extended interface automata (RTEIA which adds clearer and more detailed temporal information description by the application of time words. We also establish the input interface automaton for every input in order to solve the problems of input controlling and interface covering nimbly when applied in the software testing field. Detailed definitions of the RTEIA and the testing cases generation algorithm are provided in this paper. The feasibility and efficiency of this method have been verified in the testing of one real aircraft braking system.
Prof. Rakesh Mohanty; Prof H.S Behera; Khusbu Patwari; Monisha Dash; M. Lakshmi Prasanna
2011-01-01
In this paper, a new variant of Round Robin (RR) algorithm is proposed which is suitable for soft real time systems. RR algorithm performs optimally in timeshared systems, but it is not suitable for soft real time systems. Because it gives more number of context switches, larger waiting time and larger response time. We have proposed a novel algorithm, known as Priority Based Dynamic Round Robin Algorithm(PBDRR), which calculates intelligent time slice for individual processes and changes aft...
Real-time Algorithms for Sparse Neuronal System Identification.
Sheikhattar, Alireza; Babadi, Behtash
2016-08-01
We consider the problem of sparse adaptive neuronal system identification, where the goal is to estimate the sparse time-varying neuronal model parameters in an online fashion from neural spiking observations. We develop two adaptive filters based on greedy estimation techniques and regularized log-likelihood maximization. We apply the proposed algorithms to simulated spiking data as well as experimentally recorded data from the ferret's primary auditory cortex during performance of auditory tasks. Our results reveal significant performance gains achieved by the proposed algorithms in terms of sparse identification and trackability, compared to existing algorithms.
Extended kinetic model of real-time polymerase chain reaction process
Fedorov, A. A.; Sochivko, D. G.; Varlamov, D. A.; Kurochkin, V. E.
2016-11-01
Real-time polymerase chain reaction (real-time PCR) is the main molecular genetic method used for qualitative and quantitative analysis of specific nucleic acid sequences in many areas of biomedical research. Theoretical study of pCr models allows to estimate the influence of various reaction components and parameters, and to determine the unknown parameter values by approximating the experimental real-time PCR curves. An extended kinetic model of real-time PCR is presented. The model takes into account the enzyme activity based on Michaelis-Menten kinetics, the hybridization of complementary DNA fragments, the presence of a fluorescent probe used for detection of the reaction products, and the temperature dependence of primers and probe hybridization.
Low-Energy Real-Time OS Using Voltage Scheduling Algorithm for Variable Voltage Processors
Okuma, Takanori; Yasuura, Hiroto
2001-01-01
This paper presents a real-time OS based on $ mu $ITRON using proposed voltage scheduling algorithm for variable voltage processors which can vary supply voltage dynamically. The proposed voltage scheduling algorithms assign voltage level for each task dynamically in order to minimize energy consumption under timing constraints. Using the presented real-time OS, running tasks with low supply voltage leads to drastic energy reduction. In addition, the presented voltage scheduling algorithm is ...
Self-learning Fuzzy Controllers Based On a Real-time Reinforcement Genetic Algorithm
FANG Jian-an; MIAO Qing-ying; GUO Zhao-xia; SHAO Shi-huang
2002-01-01
This paper presents a novel method for constructing fuzzy controllers based on a real time reinforcement genetic algorithm. This methodology introduces the real-time learning capability of neural networks into globally searching process of genetic algorithm, aiming to enhance the convergence rate and real-time learning ability of genetic algorithm, which is then used to construct fuzzy controllers for complex dynamic systems without any knowledge about system dynamics and prior control experience. The cart-pole system is employed as a test bed to demonstrate the effectiveness of the proposed control scheme, and the robustness of the acquired fuzzy controller with comparable result.
Yongfeng Yin
2010-12-01
Full Text Available In this paper, formal methods were introduced into the real-time embedded software testing field and a real-time extended finite state machine, called rt_EFSM, was studied firstly. And then, the process of the integrated application based on real-time extended Unified Modeling Language (UML and improved formal method in real-time embedded software testing are put forward. Furthermore, the extension scheme of the real-time UML, including the improvement and extension of state transitions and time constraints described mechanism, and the conversion method from real-time UML to rt_EFSM ware proposed. Finally, combined with the testing process of flight control software of an unmanned aerial vehicle (UAV, a method to generate the time-extended UIO sequence (ex_UIO was put forward. Finally, the method to generate test cases automatically according to ex_UIO sequence was brought forward. The method proposed in this paper can fully make use of the advantages of tool resources of the UML which has been as the industry standard, but also the advantages of formal methods in accuracy, effectiveness and automation support.
Enabling demand response by extending the European electricity markets with a real-time market
Nyeng, P.; Kok, K.; Pineda, S.; Grande, O.; Sprooten, J.; Hebb, B.; Nieuwenhout, F.
2013-01-01
The EcoGrid concept proposes to extend the current wholesale electricity market to allow participation of Distributed Energy Resources (DERs) and domestic end-consumers in system balancing. Taking advantage of the smart grid technology, the EcoGrid market publishes the real-time prices that entail a
A real-time algorithm for predicting core temperature in humans.
Gribok, Andrei V; Buller, Mark J; Hoyt, Reed W; Reifman, Jaques
2010-07-01
In this paper, we present a real-time implementation of a previously developed offline algorithm for predicting core temperature in humans. The real-time algorithm uses a zero-phase Butterworth digital filter to smooth the data and an autoregressive (AR) model to predict core temperature. The performance of the algorithm is assessed in terms of its prediction accuracy, quantified by the root mean squared error (RMSE), and in terms of prediction uncertainty, quantified by statistically based prediction intervals (PIs). To evaluate the performance of the algorithm, we simulated real-time implementation using core-temperature data collected during two different field studies, involving ten different individuals. One of the studies includes a case of heat illness suffered by one of the participants. The results indicate that although the real-time predictions yielded RMSEs that are larger than those of the offline algorithm, the real-time algorithm does produce sufficiently accurate predictions for practically meaningful prediction horizons (approximately 20 min). The algorithm reached alert (39 degrees C) and alarm (39.5 degrees C) thresholds for the heat-ill individual but did not even attain the alert threshold for the other individuals, demonstrating the algorithm's good sensitivity and specificity. The PIs reflected, in an intuitively expected manner, the uncertainty associated with real-time forecast as a function of prediction horizon and core-temperature variability. The results also corroborate the feasibility of "universal" AR models, where an offline-developed model based on one individual's data could be used to predict any other individual in real time. We conclude that the real-time implementation of the algorithm confirms the attributes observed in the offline version and, hence, could be considered as a warning tool for impending heat illnesses.
Real time eye tracking using Kalman extended spatio-temporal context learning
Munir, Farzeen; Minhas, Fayyaz ul Amir Asfar; Jalil, Abdul; Jeon, Moongu
2017-06-01
Real time eye tracking has numerous applications in human computer interaction such as a mouse cursor control in a computer system. It is useful for persons with muscular or motion impairments. However, tracking the movement of the eye is complicated by occlusion due to blinking, head movement, screen glare, rapid eye movements, etc. In this work, we present the algorithmic and construction details of a real time eye tracking system. Our proposed system is an extension of Spatio-Temporal context learning through Kalman Filtering. Spatio-Temporal Context Learning offers state of the art accuracy in general object tracking but its performance suffers due to object occlusion. Addition of the Kalman filter allows the proposed method to model the dynamics of the motion of the eye and provide robust eye tracking in cases of occlusion. We demonstrate the effectiveness of this tracking technique by controlling the computer cursor in real time by eye movements.
Real time algorithm temperature compensation in tunable laser / VCSEL based WDM-PON system
Iglesias Olmedo, Miguel; Rodes Lopez, Roberto; Pham, Tien Thang
2012-01-01
We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C.......We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C....
Task 1. Monitoring real time materials degradation. NRC extended In-situ and real-time Monitoring
Bakhtiari, Sasan [Argonne National Lab. (ANL), Argonne, IL (United States)
2012-03-01
The overall objective of this project was to perform a scoping study to identify, in concert with the nuclear industry, those sensors and techniques that have the most promising commercial viability and fill a critical inspection or monitoring need. Candidates to be considered include sensors to monitor real-time material degradation, characterize residual stress, monitor and inspect component fabrication, assess radionuclide and associated chemical species concentrations in ground water and soil, characterize fuel properties, and monitor severe accident conditions. Under Task 1—Monitoring Real-Time Materials Degradation—scoping studies were conducted to assess the feasibility of potential inspection and monitoring technologies (i.e., a combination of sensors, advanced signal processing techniques, and data analysis methods) that could be utilized in LWR and/or advanced reactor applications for continuous monitoring of degradation in-situ. The goal was to identify those techniques that appear to be the most promising, i.e., those that are closest to being both technically and commercially viable and that the nuclear industry is most likely to pursue. Current limitations and associated issues that must be overcome before commercial application of certain techniques have also been addressed.
Integrating Real-Time Analysis With The Dendritic Cell Algorithm Through Segmentation
Gu, Feng; Aickelin, Uwe
2010-01-01
As an immune inspired algorithm, the Dendritic Cell Algorithm (DCA) has been applied to a range of problems, particularly in the area of intrusion detection. Ideally, the intrusion detection should be performed in real-time, to continuously detect misuses as soon as they occur. Consequently, the analysis process performed by an intrusion detection system must operate in real-time or near-to real-time. The analysis process of the DCA is currently performed offline, therefore to improve the algorithm's performance we suggest the development of a real-time analysis component. The initial step of the development is to apply segmentation to the DCA. This involves segmenting the current output of the DCA into slices and performing the analysis in various ways. Two segmentation approaches are introduced and tested in this paper, namely antigen based segmentation (ABS) and time based segmentation (TBS). The results of the corresponding experiments suggest that applying segmentation produces different and significantl...
Design and FPGA implementation of real-time automatic image enhancement algorithm
Dong, GuoWei; Hou, ZuoXun; Tang, Qi; Pan, Zheng; Li, Xin
2016-11-01
In order to improve image processing quality and boost processing rate, this paper proposes an real-time automatic image enhancement algorithm. It is based on the histogram equalization algorithm and the piecewise linear enhancement algorithm, and it calculate the relationship of the histogram and the piecewise linear function by analyzing the histogram distribution for adaptive image enhancement. Furthermore, the corresponding FPGA processing modules are designed to implement the methods. Especially, the high-performance parallel pipelined technology and inner potential parallel processing ability of the modules are paid more attention to ensure the real-time processing ability of the complete system. The simulations and the experimentations show that the algorithm is based on the design and implementation of FPGA hardware circuit less cost on hardware, high real-time performance, the good processing performance in different sceneries. The algorithm can effectively improve the image quality, and would have wide prospect on imaging processing field.
Real-time Design Constraints in Implementing Active Vibration Control Algorithms
Mohammed Alamgir Hossain; Mohammad Osman Tokhi
2006-01-01
Although computer architectures incorporate fast processing hardware resources, high performance real-time implementation of a complex control algorithm requires an efficient design and software coding of the algorithm so as to exploit special features of the hardware and avoid associated architecture shortcomings. This paper presents an investigation into the analysis and design mechanisms that will lead to reduction in the execution time in implementing real-time control algorithms. The proposed mechanisms are exemplified by means of one algorithm, which demonstrates their applicability to real-time applications. An active vibration control (AVC) algorithm for a flexible beam system simulated using the finite difference (FD) method is considered to demonstrate the effectiveness of the proposed methods. A comparative performance evaluation of the proposed design mechanisms is presented and discussed through a set of experiments.
A Mixed Real-time Algorithm for the Forward Kinematics of Stewart Parallel Manipulator
WANG Sun-an; WAN Ya-min
2006-01-01
Aimed at the real-time forward kinematics solving problem of Stewart parallel manipulator in the control course, a mixed algorithm combining immune evolutionary algorithm and numerical iterative scheme is proposed. Firstly taking advantage of simpleness of inverse kinematics, the forward kinematics is transformed to an optimal problem. Immune evolutionary algorithm is employed to find approximate solution of this optimal problem in manipulator's workspace. Then using above solution as iterative initialization, a speedy numerical iterative scheme is proposed to get more precise solution. In the manipulator running course, the iteration initialization can be selected as the last period position and orientation. Because the initialization is closed to correct solution, solving precision is high and speed is rapid enough to satisfy real-time requirement. This mixed forward kinematics algorithm is applied to real Stewart parallel manipulator in the real-time control course. The examination result shows that the algorithm is very efficient and practical.
Bosch, Carl; Degirmenci, Soysal; Barlow, Jason; Mesika, Assaf; Politte, David G.; O'Sullivan, Joseph A.
2016-05-01
X-ray computed tomography reconstruction for medical, security and industrial applications has evolved through 40 years of experience with rotating gantry scanners using analytic reconstruction techniques such as filtered back projection (FBP). In parallel, research into statistical iterative reconstruction algorithms has evolved to apply to sparse view scanners in nuclear medicine, low data rate scanners in Positron Emission Tomography (PET) [5, 7, 10] and more recently to reduce exposure to ionizing radiation in conventional X-ray CT scanners. Multiple approaches to statistical iterative reconstruction have been developed based primarily on variations of expectation maximization (EM) algorithms. The primary benefit of EM algorithms is the guarantee of convergence that is maintained when iterative corrections are made within the limits of convergent algorithms. The primary disadvantage, however is that strict adherence to correction limits of convergent algorithms extends the number of iterations and ultimate timeline to complete a 3D volumetric reconstruction. Researchers have studied methods to accelerate convergence through more aggressive corrections [1], ordered subsets [1, 3, 4, 9] and spatially variant image updates. In this paper we describe the development of an AM reconstruction algorithm with accelerated convergence for use in a real-time explosive detection application for aviation security. By judiciously applying multiple acceleration techniques and advanced GPU processing architectures, we are able to perform 3D reconstruction of scanned passenger baggage at a rate of 75 slices per second. Analysis of the results on stream of commerce passenger bags demonstrates accelerated convergence by factors of 8 to 15, when comparing images from accelerated and strictly convergent algorithms.
Development of real-time plasma analysis and control algorithms for the TCV tokamak using SIMULINK
Felici, F., E-mail: f.felici@tue.nl [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Suisse, 1015 Lausanne (Switzerland); Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, P.O. Box 513, 5600MB Eindhoven (Netherlands); Le, H.B.; Paley, J.I.; Duval, B.P.; Coda, S.; Moret, J.-M.; Bortolon, A.; Federspiel, L.; Goodman, T.P. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Suisse, 1015 Lausanne (Switzerland); Hommen, G. [FOM-Institute DIFFER, Association EURATOM-FOM, Nieuwegein (Netherlands); Eindhoven University of Technology, Department of Mechanical Engineering, Control Systems Technology Group, P.O. Box 513, 5600MB Eindhoven (Netherlands); Karpushov, A.; Piras, F.; Pitzschke, A. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Suisse, 1015 Lausanne (Switzerland); Romero, J. [National Laboratory of Fusion, EURATOM-CIEMAT, Madrid (Spain); Sevillano, G. [Department of Automatic Control and Systems Engineering, Bilbao University of the Basque Country, Bilbao (Spain); Sauter, O.; Vijvers, W. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association EURATOM-Suisse, 1015 Lausanne (Switzerland)
2014-03-15
Highlights: • A new digital control system for the TCV tokamak has been commissioned. • The system is entirely programmable by SIMULINK, allowing rapid algorithm development. • Different control system nodes can run different algorithms at varying sampling times. • The previous control system functions have been emulated and improved. • New capabilities include MHD control, profile control, equilibrium reconstruction. - Abstract: One of the key features of the new digital plasma control system installed on the TCV tokamak is the possibility to rapidly design, test and deploy real-time algorithms. With this flexibility the new control system has been used for a large number of new experiments which exploit TCV's powerful actuators consisting of 16 individually controllable poloidal field coils and 7 real-time steerable electron cyclotron (EC) launchers. The system has been used for various applications, ranging from event-based real-time MHD control to real-time current diffusion simulations. These advances have propelled real-time control to one of the cornerstones of the TCV experimental program. Use of the SIMULINK graphical programming language to directly program the control system has greatly facilitated algorithm development and allowed a multitude of different algorithms to be deployed in a short time. This paper will give an overview of the developed algorithms and their application in physics experiments.
Accuracy evaluation of a new real-time continuous glucose monitoring algorithm in hypoglycemia
Mahmoudi, Zeinab; Jensen, Morten Hasselstrøm; Johansen, Mette Dencker;
2014-01-01
UNLABELLED: Abstract Background: The purpose of this study was to evaluate the performance of a new continuous glucose monitoring (CGM) calibration algorithm and to compare it with the Guardian(®) REAL-Time (RT) (Medtronic Diabetes, Northridge, CA) calibration algorithm in hypoglycemia. SUBJECTS...
Mohanty, Rakesh; Patwari, Khusbu; Dash, Monisha; Prasanna, M Lakshmi
2011-01-01
In this paper, a new variant of Round Robin (RR) algorithm is proposed which is suitable for soft real time systems. RR algorithm performs optimally in timeshared systems, but it is not suitable for soft real time systems. Because it gives more number of context switches, larger waiting time and larger response time. We have proposed a novel algorithm, known as Priority Based Dynamic Round Robin Algorithm(PBDRR),which calculates intelligent time slice for individual processes and changes after every round of execution. The proposed scheduling algorithm is developed by taking dynamic time quantum concept into account. Our experimental results show that our proposed algorithm performs better than algorithm in [8] in terms of reducing the number of context switches, average waiting time and average turnaround time.
Using memristor crossbar structure to implement a novel adaptive real time fuzzy modeling algorithm
Afrakoti, Iman Esmaili Paeen; Shouraki, Saeed Bagheri; Merrikhbayat, Farnood
2013-01-01
Although fuzzy techniques promise fast meanwhile accurate modeling and control abilities for complicated systems, different difficulties have been re-vealed in real situation implementations. Usually there is no escape of it-erative optimization based on crisp domain algorithms. Recently memristor structures appeared promising to implement neural network structures and fuzzy algorithms. In this paper a novel adaptive real-time fuzzy modeling algorithm is proposed which uses active learning me...
Real time tracking with a silicon telescope prototype using the "artificial retina" algorithm
Abba, A.; Bedeschi, F.; Caponio, F.; Cenci, R.; Citterio, M.; Coelli, S.; Fu, J.; Geraci, A.; Grizzuti, M.; Lusardi, N.; Marino, P.; Monti, M.; Morello, M. J.; Neri, N.; Ninci, D.; Petruzzo, M.; Piucci, A.; Punzi, G.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.; Walsh, J.
2016-07-01
We present the first prototype of a silicon tracker using the artificial retina algorithm for fast track finding. The algorithm is inspired by the neurobiological mechanism of recognition of edges in mammals visual cortex. It is based on extensive parallelization and is implemented on commercial FPGAs allowing us to reconstruct real time tracks with offline-like quality and < 1 μs latencies. The practical device consists of a telescope with 8 single-sided silicon strip sensors and custom DAQ boards equipped with Xilinx Kintex 7 FPGAs that perform the readout of the sensors and the track reconstruction in real time.
Real-time tracking of deformable objects based on MOK algorithm
Junhua Yan; Zhigang Wang; Shunfei Wang
2016-01-01
Thetraditional oriented FAST and rotated BRIEF (ORB) algorithm has problems of instability and repetition of keypoints and it does not possess scale invariance. In order to deal with these drawbacks, a modified ORB (MORB) algo-rithm is proposed. In order to improve the precision of matching and tracking, this paper puts forward an MOK algo-rithm that fuses MORB and Kanade-Lucas-Tomasi (KLT). By using Kalman, the object’s state in the next frame is predicted in order to reduce the size of search window and improve the real-time performance of object tracking. The experimental results show that the MOK algorithm can accurately track objects with deformation or with background clutters, exhi- biting higher robustness and accuracy on diverse datasets. Also, the MOK algorithm has a good real-time performance with the average frame rate reaching 90.8 fps.
A Real-Time Lane Detection Algorithm Based on Intelligent CCD Parameters Regulation
Ping-shu Ge
2012-01-01
Full Text Available Lane departure warning system (LDWS has been regarded as an efficient method to lessen the damages of road traffic accident resulting from driver fatigue or inattention. Lane detection is one of the key techniques for LDWS. To overcome the contradiction between complexity of algorithm and the real-time requirement for vehicle onboard system, this paper introduces a new lane detection method based on intelligent CCD parameters regulation. In order to improve the real-time capability of the system, a CCD parameters regulating method is proposed which enhances the contrast between lane line and road surfaces and reduces image noise, so it lays a good foundation for the following lane detection. Hough transform algorithm is improved by selection and classification of seed points. Finally the lane line is extracted through some restrictions. Experimental results verify the effectiveness of the proposed method, which improves not only real-time capability but also the accuracy of the system.
Development of real time diagnostics and feedback algorithms for JET in view of the next step
Murari, A.; Barana, O. [Consorzio RFX Associazione EURATOM ENEA per la Fusione, Corso Stati Uniti 4, Padua (Italy); Felton, R.; Zabeo, L.; Piccolo, F.; Sartori, F. [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon (United Kingdom); Joffrin, E.; Mazon, D.; Laborde, L.; Moreau, D. [Association EURATOM-CEA, CEA Cadarache, 13 - Saint-Paul-lez-Durance (France); Albanese, R. [Assoc. Euratom-ENEA-CREATE, Univ. Mediterranea RC (Italy); Arena, P.; Bruno, M. [Assoc. Euratom-ENEA-CREATE, Univ.di Catania (Italy); Ambrosino, G.; Ariola, M. [Assoc. Euratom-ENEA-CREATE, Univ. Napoli Federico Napoli (Italy); Crisanti, F. [Associazone EURATOM ENEA sulla Fusione, C.R. Frascati (Italy); Luna, E. de la; Sanchez, J. [Associacion EURATOM CIEMAT para Fusion, Madrid (Spain)
2004-07-01
Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. Both diagnostics and algorithms were successfully used in several experiments, ranging from H-mode plasmas to configuration with ITBs (internal thermal barriers). Since elaboration of computationally heavy measurements is often required, significant attention was devoted to non-algorithmic methods like Digital or Cellular Neural/Nonlinear Networks. The real time hardware and software adopted architectures are also described with particular attention to their relevance to ITER. (authors)
A real-time traffic scheduling algorithm in CDMA packet networks
Zan, Lei; Heijenk, Geert; El Zarki, Magda; Gong, K.; Niu, Z.
2003-01-01
The demands for multimedia and packet data services over wireless devices have increased over the past few years. The direct impact on performance makes scheduling for real-time traffic important. This paper presents a novel scheduling algorithm called fair channel-dependent scheduling which schedul
Cook, Gerald; Lin, Ching-Fang
1980-01-01
The local linearization algorithm is presented as a possible numerical integration scheme to be used in real-time simulation. A second-order nonlinear example problem is solved using different methods. The local linearization approach is shown to require less computing time and give significant...... improvement in accuracy over the classical second-order integration methods....
Development of real-time plasma analysis and control algorithms for the TCV tokamak using Simulink
Felici, F.; Le, H. B.; J. I. Paley,; Duval, B. P.; Coda, S.; Moret, J. M.; Bortolon, A.; L. Federspiel,; Goodman, T. P.; Hommen, G.; A. Karpushov,; Piras, F.; A. Pitzschke,; J. Romero,; G. Sevillano,; Sauter, O.; Vijvers, W.; TCV team,
2014-01-01
One of the key features of the new digital plasma control system installed on the TCV tokamak is the possibility to rapidly design, test and deploy real-time algorithms. With this flexibility the new control system has been used for a large number of new experiments which exploit TCV's powerful
A Real-Time evaluation system for a state-of-charge indication algorithm
Pop, V.; Bergveld, H.J.; Notten, P.H.L.; Regtien, Paulus P.L.
2005-01-01
The known methods of State-of-Charge (SoC) indication in portable applications are not accurate enough under all practical conditions. This paper describes a real- time evaluation LabVIEW system for an SoC algorithm, that calculates the SoC in [%] and also the remaining run-time available under the
A Real-Time evaluation system for a state-of-charge indication algorithm
Pop, V.; Bergveld, H.J.; Notten, P.H.L.; Regtien, P.P.L.
2005-01-01
The known methods of State-of-Charge (SoC) indication in portable applications are not accurate enough under all practical conditions. This paper describes a real- time evaluation LabVIEW system for an SoC algorithm, that calculates the SoC in [%] and also the remaining run-time available under the
Noureddine Aloui
2015-02-01
Full Text Available This paper presents an optimized speech compression algorithm using discrete wavelet transform, and its real time implementation on fixed-point digital signal processor (DSP. The optimized speech compression algorithm presents the advantages to ensure low complexity, low bit rate and achieve high speech coding efficiency, and this by adding a voice activity detector (VAD module before the application of the discrete wavelet transform. The VAD module avoids the computation of the discrete wavelet coefficients during the inactive voice signal. In addition, a real-time implementation of the optimized speech compression algorithm is performed using fixed-point processor. The optimized and the original algorithms are evaluated and compared in terms of CPU time (sec, Cycle count (MCPS, Memory consumption (Ko, Compression Ratio (CR, Signal to Noise Ratio (SNR, Peak Signal to Noise Ratio (PSNR and Normalized Root Mean Square Error (NRMSE.
Real-Time Scheduling in Heterogeneous Systems Considering Cache Reload Time Using Genetic Algorithms
Miryani, Mohammad Reza; Naghibzadeh, Mahmoud
Since optimal assignment of tasks in a multiprocessor system is, in almost all practical cases, an NP-hard problem, in recent years some algorithms based on genetic algorithms have been proposed. Some of these algorithms have considered real-time applications with multiple objectives, total tardiness, completion time, etc. Here, we propose a suboptimal static scheduler of nonpreemptable tasks in hard real-time heterogeneous multiprocessor systems considering time constraints and cache reload time. The approach makes use of genetic algorithm to minimize total completion time and number of processors used, simultaneously. One important issue which makes this research different from previous ones is cache reload time. The method is implemented and the results are compared against a similar method.
A time-consistent video segmentation algorithm designed for real-time implementation
Elhassani, Mohammed; Rivasseau, Delphine; Jehan-Besson, Stéphanie; Revenu, Marinette; Tschumperlé, David; Brun, Luc; Duranton, Marc
2006-01-01
International audience; In this paper, we propose a time consistent video segmentation algorithm designed for real-time implementation. Our segmentation algorithm is based on a region merging process that combines both spatial and motion information. The spatial segmentation takes benefit of an adaptive decision rule and a specific order of merging. Our method has proven to be efficient for the segmentation of natural images (flat or textured regions) with few parameters to be set. Temporal c...
2013-10-01
Insider Threat Control: Using Plagiarism Detection Algorithms to Prevent Data Exfiltration in Near Real Time Todd Lewellen George J. Silowash...algorithms used in plagiarism detection software—to search the index for bodies of text similar to the text found in the outgoing web request. If the...2. REPORT DATE October 2013 3. REPORT TYPE AND DATES COVERED Final 4. TITLE AND SUBTITLE Insider Threat Control: Using Plagiarism Detection
Bukhari, W; Hong, S-M
2015-01-07
Motion-adaptive radiotherapy aims to deliver a conformal dose to the target tumour with minimal normal tissue exposure by compensating for tumour motion in real time. The prediction as well as the gating of respiratory motion have received much attention over the last two decades for reducing the targeting error of the treatment beam due to respiratory motion. In this article, we present a real-time algorithm for predicting and gating respiratory motion that utilizes a model-based and a model-free Bayesian framework by combining them in a cascade structure. The algorithm, named EKF-GPR(+), implements a gating function without pre-specifying a particular region of the patient's breathing cycle. The algorithm first employs an extended Kalman filter (LCM-EKF) to predict the respiratory motion and then uses a model-free Gaussian process regression (GPR) to correct the error of the LCM-EKF prediction. The GPR is a non-parametric Bayesian algorithm that yields predictive variance under Gaussian assumptions. The EKF-GPR(+) algorithm utilizes the predictive variance from the GPR component to capture the uncertainty in the LCM-EKF prediction error and systematically identify breathing points with a higher probability of large prediction error in advance. This identification allows us to pause the treatment beam over such instances. EKF-GPR(+) implements the gating function by using simple calculations based on the predictive variance with no additional detection mechanism. A sparse approximation of the GPR algorithm is employed to realize EKF-GPR(+) in real time. Extensive numerical experiments are performed based on a large database of 304 respiratory motion traces to evaluate EKF-GPR(+). The experimental results show that the EKF-GPR(+) algorithm effectively reduces the prediction error in a root-mean-square (RMS) sense by employing the gating function, albeit at the cost of a reduced duty cycle. As an example, EKF-GPR(+) reduces the patient-wise RMS error to 37%, 39% and
Real Time Optima Tracking Using Harvesting Models of the Genetic Algorithm
Baskaran, Subbiah; Noever, D.
1999-01-01
Tracking optima in real time propulsion control, particularly for non-stationary optimization problems is a challenging task. Several approaches have been put forward for such a study including the numerical method called the genetic algorithm. In brief, this approach is built upon Darwinian-style competition between numerical alternatives displayed in the form of binary strings, or by analogy to 'pseudogenes'. Breeding of improved solution is an often cited parallel to natural selection in.evolutionary or soft computing. In this report we present our results of applying a novel model of a genetic algorithm for tracking optima in propulsion engineering and in real time control. We specialize the algorithm to mission profiling and planning optimizations, both to select reduced propulsion needs through trajectory planning and to explore time or fuel conservation strategies.
Real-Time Volume Shadow using Visible-Non Visible Algorithm
Hoshang Kolivand
2011-01-01
Full Text Available Problem statement: Shadows are most important effect to make realistic games and visually appealing images, but they are poor in frame per second. Silhouette detection is most important phases to create real-time shadow. Approach: Present study describes a real-time shadow generated with volume shadow algorithm using Visible-Non Visible algorithm (VNV in virtual environment illuminated by a movable light source to improve the frame per second. Silhouette detection that is most expensive part of shadow creation was described. Triangular method and VNV method were compared. An improved algorithm for volume shadow was proposed and volume shadow using both methods in C+ Opengl implemented. Results: The VNV algorithm increases the number of Frame Per Second (FPS and as a result decreases the cost of implementation. Conclusion: A verified algorithm for volume shadow makes it easy to understand by everyone how to produce real-time shadow in outdoor and indoor virtual environment. It is possible to use it in current commercial games or other virtual reality systems.
Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint
Nagarajan, Adarsh; Nelson, Austin; Prabakar, Kumaraguru; Hoke, Andy; Asano, Marc; Ueda, Reid; Nepal, Shaili
2017-06-15
As advanced grid-support functions (AGF) become more widely used in grid-connected photovoltaic (PV) inverters, utilities are increasingly interested in their impacts when implemented in the field. These effects can be understood by modeling feeders in real-time systems and testing PV inverters using power hardware-in-the-loop (PHIL) techniques. This paper presents a novel feeder model reduction algorithm using a Monte Carlo method that enables large feeders to be solved and operated on real-time computing platforms. Two Hawaiian Electric feeder models in Synergi Electric's load flow software were converted to reduced order models in OpenDSS, and subsequently implemented in the OPAL-RT real-time digital testing platform. Smart PV inverters were added to the real-time model with AGF responses modeled after characterizing commercially available hardware inverters. Finally, hardware inverters were tested in conjunction with the real-time model using PHIL techniques so that the effects of AGFs on the choice feeders could be analyzed.
1988-05-31
COMPUTER ALGORITHMS FOR AUTOMATIC REAL-TIME DETERMINATION OF SPACE VEHICLE POTENTIALS IN VARIOUS PLASMA ENVIRONMENTS May 31, 1988 Stanley L. Spiegel...crrnaion DiviSiofl 838 12 2 DERIVATION AND TESTING OF COMPUTER ALGORITHMS FOR AUTOMATIC REAL-TIME DETERMINATION OF SPACE VEHICLE POTENTIALS IN VARIOUS...S.L., "Derivation and testing of computer algorithms for automatic real time determination of space vehicle poteuatials in various plasma
A contourlet transform based algorithm for real-time video encoding
Katsigiannis, Stamos; Papaioannou, Georgios; Maroulis, Dimitris
2012-06-01
In recent years, real-time video communication over the internet has been widely utilized for applications like video conferencing. Streaming live video over heterogeneous IP networks, including wireless networks, requires video coding algorithms that can support various levels of quality in order to adapt to the network end-to-end bandwidth and transmitter/receiver resources. In this work, a scalable video coding and compression algorithm based on the Contourlet Transform is proposed. The algorithm allows for multiple levels of detail, without re-encoding the video frames, by just dropping the encoded information referring to higher resolution than needed. Compression is achieved by means of lossy and lossless methods, as well as variable bit rate encoding schemes. Furthermore, due to the transformation utilized, it does not suffer from blocking artifacts that occur with many widely adopted compression algorithms. Another highly advantageous characteristic of the algorithm is the suppression of noise induced by low-quality sensors usually encountered in web-cameras, due to the manipulation of the transform coefficients at the compression stage. The proposed algorithm is designed to introduce minimal coding delay, thus achieving real-time performance. Performance is enhanced by utilizing the vast computational capabilities of modern GPUs, providing satisfactory encoding and decoding times at relatively low cost. These characteristics make this method suitable for applications like video-conferencing that demand real-time performance, along with the highest visual quality possible for each user. Through the presented performance and quality evaluation of the algorithm, experimental results show that the proposed algorithm achieves better or comparable visual quality relative to other compression and encoding methods tested, while maintaining a satisfactory compression ratio. Especially at low bitrates, it provides more human-eye friendly images compared to
H~ Estimation Approach to Active Noise Control: Theory, Algorithm and Real-Time Implementation
Bambang Riyanto
2003-11-01
Full Text Available This paper presents an H¥ estimation approach to active control of acoustic noise inside an enclosure. It is shown how H¥ filter theory and algorithm can be effectively applied to active noise control to provide important robustness property. Real-time implementation of the algorithm is performed on Digital Signal Processor. Experimental comparison to conventional FxLMS algorithm for active noise control is presented for both single channel and multichannel cases. While providing some new results, this paper also serves as a brief review on H¥ filter theory and on active noise control.
A real-time phoneme counting algorithm and application for speech rate monitoring.
Aharonson, Vered; Aharonson, Eran; Raichlin-Levi, Katia; Sotzianu, Aviv; Amir, Ofer; Ovadia-Blechman, Zehava
2017-03-01
Adults who stutter can learn to control and improve their speech fluency by modifying their speaking rate. Existing speech therapy technologies can assist this practice by monitoring speaking rate and providing feedback to the patient, but cannot provide an accurate, quantitative measurement of speaking rate. Moreover, most technologies are too complex and costly to be used for home practice. We developed an algorithm and a smartphone application that monitor a patient's speaking rate in real time and provide user-friendly feedback to both patient and therapist. Our speaking rate computation is performed by a phoneme counting algorithm which implements spectral transition measure extraction to estimate phoneme boundaries. The algorithm is implemented in real time in a mobile application that presents its results in a user-friendly interface. The application incorporates two modes: one provides the patient with visual feedback of his/her speech rate for self-practice and another provides the speech therapist with recordings, speech rate analysis and tools to manage the patient's practice. The algorithm's phoneme counting accuracy was validated on ten healthy subjects who read a paragraph at slow, normal and fast paces, and was compared to manual counting of speech experts. Test-retest and intra-counter reliability were assessed. Preliminary results indicate differences of -4% to 11% between automatic and human phoneme counting. Differences were largest for slow speech. The application can thus provide reliable, user-friendly, real-time feedback for speaking rate control practice.
Closed form and geometric algorithms for real-time control of an avatar
Semwall, S.K.; Hightower, R.; Stansfield, S.
1995-12-31
In a virtual environment with multiple participants, it is necessary that the user`s actions be replicated by synthetic human forms. Whole body digitizers would be the most realistic solution for capturing the individual participant`s human form, however the best of the digitizers available are not interactive and are therefore not suitable for real-time interaction. Usually, a limited number of sensors are used as constraints on the synthetic human form. Inverse kinematics algorithms are applied to satisfy these sensor constraints. These algorithms result in slower interaction because of their iterative nature, especially when there are a large number of participants. To support real-time interaction in a virtual environment, there is a need to generate closed for solutions and fast searching algorithms. In this paper, a new closed form solution for the arms (and legs) is developed using two magnetic sensors. In developing this solution, we use the biomechanical relationship between the lower arm and the upper arm to provide an analytical, non-iterative solution, We have also outlined a solution for the whole human body by using up to ten magnetic sensors to break the human skeleton into smaller kinematic chains. In developing our algorithms, we use the knowledge of natural body postures to generate faster solutions for real-time interaction.
A Robust Algorithm for Real-time Endpoint Detection in the Noisy Mobile Environments
WUBian; RENXiaolin; LIUChongqing; ZHANGYaxin
2003-01-01
In speech recognition, the endpoint detection must be robust to noise. In low SNR situations, the conventional energy-based endpoint detection algorithms often fail and the performance of speech recognizer usually degrades distinctly, especially when in mobile environments, the background noise changes dramatically. In this paper, we propose a new algorithm that improves the endpoint detection for speech recognition in low SNR and in various noisy environments. The described algorithm not only uses multiple features but introduces a decision logic to increase the robustness in both low SNR and various noisy mobile environments. To evaluate the new algorithm, we carry out experiments in various noisy mobile environments (e.g. railway station, airport, street etc), and the performance of the algorithm is significantly improved, especially in low SNR situations. At the same time, the proposed algorithm has a low complexity and is suitable for real time embedded systems.
A Time-Consistent Video Segmentation Algorithm Designed for Real-Time Implementation
M. El Hassani
2008-01-01
Temporal consistency of the segmentation is ensured by incorporating motion information through the use of an improved change-detection mask. This mask is designed using both illumination differences between frames and region segmentation of the previous frame. By considering both pixel and region levels, we obtain a particularly efficient algorithm at a low computational cost, allowing its implementation in real-time on the TriMedia processor for CIF image sequences.
One-of-a-kind Production: Controller Algorithms for Real-time Control
Ørum-Hansen, Claus
PhD Dissertation.IPS2-programme - Integrated Production Systems - supportet by the Danish Technical Research Council, STVF.The project is a part of the IPS 2 research Programmme - Integrated Production System - with focus on one-of-a-kind production.The research area deals with controller...... algorithms for real-time control. The work includes practical cases from ship design and manufacturing. Cooperation with Odense Steel Shipyard....
Research and Realization of the HJ-1C Real-time Software Frame Synchronization Algorithm
Hou Yang-shuan; Shi Tao; Hu Yu-xin
2014-01-01
Conventional software frame synchronization methods are inefficient in processing huge continuous data without synchronization words. To improve the processing speed, a real-time synchronization algorithm is proposed based on reverse searching. Satellite data are grouped and searched in the reverse direction to avoid searching for synchronization words in huge continuous invalid data; thus, the frame synchronization speed is improved enormously. The fastest processing speed is up to 15445.9 M...
Wenbo Wu; Jiahong Liang; Xinyu Yao; Baohong Liu
2014-01-01
This paper addresses the problem of task allocation in real-time distributed systems with the goal of maximizing the system reliability, which has been shown to be NP-hard. We take account of the deadline constraint to formulate this problem and then propose an algorithm called chaotic adaptive simulated annealing (XASA) to solve the problem. Firstly, XASA begins with chaotic optimization which takes a chaotic walk in the solution space and generates several local minima; secondly XASA improv...
Hao Lu
2016-01-01
Full Text Available Bio-inspired imaging polarization navigation which can provide navigation information and is capable of sensing polarization information has advantages of high-precision and anti-interference over polarization navigation sensors that use photodiodes. Although all types of imaging polarimeters exist, they may not qualify for the research on the imaging polarization navigation algorithm. To verify the algorithm, a real-time imaging orientation determination system was designed and implemented. Essential calibration procedures for the type of system that contained camera parameter calibration and the inconsistency of complementary metal oxide semiconductor calibration were discussed, designed, and implemented. Calibration results were used to undistort and rectify the multi-camera system. An orientation determination experiment was conducted. The results indicated that the system could acquire and compute the polarized skylight images throughout the calibrations and resolve orientation by the algorithm to verify in real-time. An orientation determination algorithm based on image processing was tested on the system. The performance and properties of the algorithm were evaluated. The rate of the algorithm was over 1 Hz, the error was over 0.313°, and the population standard deviation was 0.148° without any data filter.
A Novel Face Segmentation Algorithm from a Video Sequence for Real-Time Face Recognition
Sudhaker Samuel RD
2007-01-01
Full Text Available The first step in an automatic face recognition system is to localize the face region in a cluttered background and carefully segment the face from each frame of a video sequence. In this paper, we propose a fast and efficient algorithm for segmenting a face suitable for recognition from a video sequence. The cluttered background is first subtracted from each frame, in the foreground regions, a coarse face region is found using skin colour. Then using a dynamic template matching approach the face is efficiently segmented. The proposed algorithm is fast and suitable for real-time video sequence. The algorithm is invariant to large scale and pose variation. The segmented face is then handed over to a recognition algorithm based on principal component analysis and linear discriminant analysis. The online face detection, segmentation, and recognition algorithms take an average of 0.06 second on a 3.2 GHz P4 machine.
Chang, Chein-I
2017-01-01
This book explores recursive architectures in designing progressive hyperspectral imaging algorithms. In particular, it makes progressive imaging algorithms recursive by introducing the concept of Kalman filtering in algorithm design so that hyperspectral imagery can be processed not only progressively sample by sample or band by band but also recursively via recursive equations. This book can be considered a companion book of author’s books, Real-Time Progressive Hyperspectral Image Processing, published by Springer in 2016. Explores recursive structures in algorithm architecture Implements algorithmic recursive architecture in conjunction with progressive sample and band processing Derives Recursive Hyperspectral Sample Processing (RHSP) techniques according to Band-Interleaved Sample/Pixel (BIS/BIP) acquisition format Develops Recursive Hyperspectral Band Processing (RHBP) techniques according to Band SeQuential (BSQ) acquisition format for hyperspectral data.
An Optimal Scheduling Algorithm for Real Time Applications in Grid System
S.Baghavathi Priya
2013-01-01
Full Text Available The objective of the proposed work is to use an optimal scheduling algorithm for real-time application. A grid is considered to be an infrastructure that bonds and unifies globally remote and diverse resources in order to provide computing support for a wide range of applications. Real time applications in an industrialized technological infrastructure such as telecommunication systems, factories, defense systems, aircraft and space stations pose relatively rigid requirements on their performance. Aircraft scheduling represents the best example of real-time applications. The main focus of this work is to check the time taken for turn-around activities which comprises of taxi in, load/unload baggage, deboarding, water fueling, cleaning, catering, boarding, de-icing, take off processes, thus relating in the lowest flight delays and shortest waiting time. The optimal scheduling algorithm is used for aircraft take-offs. The penalties are associated with proper scheduling but delayed turn around activities, improper scheduling and early/late takeoffs.
Weizhe Zhang
2014-01-01
Full Text Available Energy consumption in computer systems has become a more and more important issue. High energy consumption has already damaged the environment to some extent, especially in heterogeneous multiprocessors. In this paper, we first formulate and describe the energy-aware real-time task scheduling problem in heterogeneous multiprocessors. Then we propose a particle swarm optimization (PSO based algorithm, which can successfully reduce the energy cost and the time for searching feasible solutions. Experimental results show that the PSO-based energy-aware metaheuristic uses 40%–50% less energy than the GA-based and SFLA-based algorithms and spends 10% less time than the SFLA-based algorithm in finding the solutions. Besides, it can also find 19% more feasible solutions than the SFLA-based algorithm.
GPU-accelerated phase extraction algorithm for interferograms: a real-time application
Zhu, Xiaoqiang; Wu, Yongqian; Liu, Fengwei
2016-11-01
Optical testing, having the merits of non-destruction and high sensitivity, provides a vital guideline for optical manufacturing. But the testing process is often computationally intensive and expensive, usually up to a few seconds, which is sufferable for dynamic testing. In this paper, a GPU-accelerated phase extraction algorithm is proposed, which is based on the advanced iterative algorithm. The accelerated algorithm can extract the right phase-distribution from thirteen 1024x1024 fringe patterns with arbitrary phase shifts in 233 milliseconds on average using NVIDIA Quadro 4000 graphic card, which achieved a 12.7x speedup ratio than the same algorithm executed on CPU and 6.6x speedup ratio than that on Matlab using DWANING W5801 workstation. The performance improvement can fulfill the demand of computational accuracy and real-time application.
Wenbo Wu
2014-01-01
Full Text Available This paper addresses the problem of task allocation in real-time distributed systems with the goal of maximizing the system reliability, which has been shown to be NP-hard. We take account of the deadline constraint to formulate this problem and then propose an algorithm called chaotic adaptive simulated annealing (XASA to solve the problem. Firstly, XASA begins with chaotic optimization which takes a chaotic walk in the solution space and generates several local minima; secondly XASA improves SA algorithm via several adaptive schemes and continues to search the optimal based on the results of chaotic optimization. The effectiveness of XASA is evaluated by comparing with traditional SA algorithm and improved SA algorithm. The results show that XASA can achieve a satisfactory performance of speedup without loss of solution quality.
IMPLEMENTATION OF A REAL-TIME STACKING ALGORITHM IN A PHOTOGRAMMETRIC DIGITAL CAMERA FOR UAVS
A. Audi
2017-08-01
Full Text Available In the recent years, unmanned aerial vehicles (UAVs have become an interesting tool in aerial photography and photogrammetry activities. In this context, some applications (like cloudy sky surveys, narrow-spectral imagery and night-vision imagery need a longexposure time where one of the main problems is the motion blur caused by the erratic camera movements during image acquisition. This paper describes an automatic real-time stacking algorithm which produces a high photogrammetric quality final composite image with an equivalent long-exposure time using several images acquired with short-exposure times. Our method is inspired by feature-based image registration technique. The algorithm is implemented on the light-weight IGN camera, which has an IMU sensor and a SoC/FPGA. To obtain the correct parameters for the resampling of images, the presented method accurately estimates the geometrical relation between the first and the Nth image, taking into account the internal parameters and the distortion of the camera. Features are detected in the first image by the FAST detector, than homologous points on other images are obtained by template matching aided by the IMU sensors. The SoC/FPGA in the camera is used to speed up time-consuming parts of the algorithm such as features detection and images resampling in order to achieve a real-time performance as we want to write only the resulting final image to save bandwidth on the storage device. The paper includes a detailed description of the implemented algorithm, resource usage summary, resulting processing time, resulting images, as well as block diagrams of the described architecture. The resulting stacked image obtained on real surveys doesn’t seem visually impaired. Timing results demonstrate that our algorithm can be used in real-time since its processing time is less than the writing time of an image in the storage device. An interesting by-product of this algorithm is the 3D rotation
Performance Evaluation of New Joint EDF-RM Scheduling Algorithm for Real Time Distributed System
Rashmi Sharma
2014-01-01
Full Text Available In Real Time System, the achievement of deadline is the main target of every scheduling algorithm. Earliest Deadline First (EDF, Rate Monotonic (RM, and least Laxity First are some renowned algorithms that work well in their own context. As we know, there is a very common problem Domino's effect in EDF that is generated due to overloading condition (EDF is not working well in overloading situation. Similarly, performance of RM is degraded in underloading condition. We can say that both algorithms are complements of each other. Deadline missing in both events happens because of their utilization bounding strategy. Therefore, in this paper we are proposing a new scheduling algorithm that carries through the drawback of both existing algorithms. Joint EDF-RM scheduling algorithm is implemented in global scheduler that permits task migration mechanism in between processors in the system. In order to check the improved behavior of proposed algorithm we perform simulation. Results are achieved and evaluated in terms of Success Ratio (SR, Average CPU Utilization (ECU, Failure Ratio (FR, and Maximum Tardiness parameters. In the end, the results are compared with the existing (EDF, RM, and D_R_EDF algorithms. It has been shown that the proposed algorithm performs better during overloading condition as well in underloading condition.
Real time processing of neutron monitor data using the edge editor algorithm
Mavromichalaki Helen
2012-09-01
Full Text Available The nucleonic component of the secondary cosmic rays is measured by the worldwide network of neutron monitors (NMs. In most cases, a NM station publishes the measured data in a real time basis in order to be available for instant use from the scientific community. The space weather centers and the online applications such as the ground level enhancement (GLE alert make use of the online data and are highly dependent on their quality. However, the primary data in some cases are distorted due to unpredictable instrument variations. For this reason, the real time primary data processing of the measured data of a station is necessary. The general operational principle of the correction algorithms is the comparison between the different channels of a NM, taking advantage of the fact that a station hosts a number of identical detectors. Median editor, Median editor plus and Super editor are some of the correction algorithms that are being used with satisfactory results. In this work an alternative algorithm is proposed and analyzed. The new algorithm uses a statistical approach to define the distribution of the measurements and introduces an error index which is used for the correction of the measurements that deviate from this distribution.
Heat wave over India during summer 2015: an assessment of real time extended range forecast
Pattanaik, D. R.; Mohapatra, M.; Srivastava, A. K.; Kumar, Arun
2017-08-01
Hot winds are the marked feature of summer season in India during late spring preceding the climatological onset of the monsoon season in June. Some years the conditions becomes very vulnerable with the maximum temperature ( T max) exceeding 45 °C for many days over parts of north-western, eastern coastal states of India and Indo-Gangetic plain. During summer of 2015 (late May to early June) eastern coastal states, central and northwestern parts of India experienced severe heat wave conditions leading to loss of thousands of human life in extreme high temperature conditions. It is not only the loss of human life but also the animals and birds were very vulnerable to this extreme heat wave conditions. In this study, an attempt is made to assess the performance of real time extended range forecast (forecast up to 3 weeks) of this scorching T max based on the NCEP's Climate Forecast System (CFS) latest version coupled model (CFSv2). The heat wave condition was very severe during the week from 22 to 28 May with subsequent week from 29 May to 4 June also witnessed high T max over many parts of central India including eastern coastal states of India. The 8 ensemble members of operational CFSv2 model are used once in a week to prepare the weekly bias corrected deterministic (ensemble mean) T max forecast for 3 weeks valid from Friday to Thursday coinciding with the heat wave periods of 2015. Using the 8 ensemble members separately and the CFSv2 corresponding hindcast climatology the probability of above and below normal T max is also prepared for the same 3 weeks. The real time deterministic and probabilistic forecasts did indicate impending heat wave over many parts of India during late May and early June of 2015 associated with strong northwesterly wind over main land mass of India, delaying the sea breeze, leading to heat waves over eastern coastal regions of India. Thus, the capability of coupled model in providing early warning of such killer heat wave can be very
A novel time-domain signal processing algorithm for real time ventricular fibrillation detection
Monte, G. E.; Scarone, N. C.; Liscovsky, P. O.; Rotter S/N, P.
2011-12-01
This paper presents an application of a novel algorithm for real time detection of ECG pathologies, especially ventricular fibrillation. It is based on segmentation and labeling process of an oversampled signal. After this treatment, analyzing sequence of segments, global signal behaviours are obtained in the same way like a human being does. The entire process can be seen as a morphological filtering after a smart data sampling. The algorithm does not require any ECG digital signal pre-processing, and the computational cost is low, so it can be embedded into the sensors for wearable and permanent applications. The proposed algorithms could be the input signal description to expert systems or to artificial intelligence software in order to detect other pathologies.
Jharna Majumdar
2002-07-01
Full Text Available "Automatic detection and tracking of interesting targets from a sequence of images obtained from a reconnaissance platform is an interesting area of research for defence-related applications. Image registration is the basic step used in target tracking application. The paper briefly reviews some of the image registration algorithms, analyse their performance using a suitable image processing hardware, and selects the most suitable algorithm for a real-time target tracking application using cubic-spline model and spline model Kalman filter for the prediction of an occluded target. The algorithms developed are implemented in a ground-based image exploitation system (GIES developed at the Aeronautical Development Establishment for unmanned aerial vehicle application, and the results presented for the images obtained during actual flight trial.
A REAL-TIME C-V CLUSTERING ALGORITHM FOR WEB-MINING
Li Haiying; Zhuang Zhenquan; Li Bin; Wan Ke
2002-01-01
In this letter, a real-time C-V (Characteristic-Vector) clustering algorithm is put forth to treat with vast action data which are dynamically collected from web site. The algorithm cites the concept of C-V to denote characteristic, synchronously it adopts two-value [0,1]input and self-definition vigilance parameter to design clustering-architecture. Vector Degree of Matching (VDM) plays a key role in the clustering algorithm, which determines the magnitude of typical characteristic. Making use of stability analysis, the classifications are confirmed to have reliably hierarchical structure when vigilance parameter shifts from 0.1 to 0.99. This non-linear relation between vigilance parameter and classification upper limit helps mining out representative classifications from net-users according to the actual web resource, then administering system can map them to web resource space to implement the intelligent configuration effectually and rapidly.
An Adaptive Genetic Algorithm for Multiprocessor Real-time Task Scheduling
LI Ya-jun; YANG Yu-hang
2009-01-01
Real-time task scheduling is of primary significance in multiprocessor systems. Meeting deadlines and achieving high system utilization are the two main objectives of task scheduling in such systems. In this paper,we represent those two goals as the minimization of the average response time and the average task laxity. To achieve this, we propose a genetic-based algorithm with problem-specific and efficient genetic operators. Adaptive control parameters are also employed in our work to improve the genetic algorithms' efficiency. The simulation results show that our proposed algorithm outperforms its counterpart considerably by up to 36% and 35% in terms of the average response time and the average task laxity,respectively.
A Hierarchical Optimization Algorithm Based on GPU for Real-Time 3D Reconstruction
Lin, Jin-hua; Wang, Lu; Wang, Yan-jie
2017-06-01
In machine vision sensing system, it is important to realize high-quality real-time 3D reconstruction in large-scale scene. The recent online approach performed well, but scaling up the reconstruction, it causes pose estimation drift, resulting in the cumulative error, usually requiring a large number of off-line operation to completely correct the error, reducing the reconstruction performance. In order to optimize the traditional volume fusion method and improve the old frame-to-frame pose estimation strategy, this paper presents a real-time CPU to Graphic Processing Unit reconstruction system. Based on a robust camera pose estimation strategy, the algorithm fuses all the RGB-D input values into an effective hierarchical optimization framework, and optimizes each frame according to the global camera attitude, eliminating the serious dependence on the tracking timeliness and continuously tracking globally optimized frames. The system estimates the global optimization of gestures (bundling) in real-time, supports for robust tracking recovery (re-positioning), and re-estimation of large-scale 3D scenes to ensure global consistency. It uses a set of sparse corresponding features, geometric and ray matching functions in one of the parallel optimization systems. The experimental results show that the average reconstruction time is 415 ms per frame, the ICP pose is estimated 20 times in 100.0 ms. For large scale 3D reconstruction scene, the system performs well in online reconstruction area, keeping the reconstruction accuracy at the same time.
Airborne SAR Real-time Imaging Algorithm Design and Implementation with CUDA on NVIDIA GPU
Meng Da-di
2013-12-01
Full Text Available Synthetic Aperture Radar (SAR image processing requires huge computation amount. Traditionally, this task runs on the workstation or server based on Central Processing Unit (CPU and is rather time-consuming, hence real-time processing of SAR data is impossible. Based on Compute Unified Device Architecture (CUDA technology, a new plan of SAR imaging algorithm operated on NVIDIA Graphic Processing Unit (GPU is proposed. The new proposal makes it possible that the data processing procedure and CPU/GPU data exchanging execute concurrently, especially when SAR data size exceeds total GPU global memory size. Multi-GPU is suitably supported by the new proposal and all of computational resources are fully exploited. It is shown by experiment on NVIDIA K20C and INTEL E5645 that the proposed solution accelerates SAR data processing by tens of times. Consequently, the GPU based SAR processing system with the proposed solution embedded is much more power saving and portable, which makes it qualified to be a real-time SAR data processing system. Experiment shows that SAR data of 36 Mega points can be processed in real-time per second by K20C with the new solution equipped.
Novel algorithm implementations in DARC: the Durham AO real-time controller
Basden, Alastair; Bitenc, Urban; Jenkins, David
2016-07-01
The Durham AO Real-time Controller has been used on-sky with the CANARY AO demonstrator instrument since 2010, and is also used to provide control for several AO test-benches, including DRAGON. Over this period, many new real-time algorithms have been developed, implemented and demonstrated, leading to performance improvements for CANARY. Additionally, the computational performance of this real-time system has continued to improve. Here, we provide details about recent updates and changes made to DARC, and the relevance of these updates, including new algorithms, to forthcoming AO systems. We present the computational performance of DARC when used on different hardware platforms, including hardware accelerators, and determine the relevance and potential for ELT scale systems. Recent updates to DARC have included algorithms to handle elongated laser guide star images, including correlation wavefront sensing, with options to automatically update references during AO loop operation. Additionally, sub-aperture masking options have been developed to increase signal to noise ratio when operating with non-symmetrical wavefront sensor images. The development of end-user tools has progressed with new options for configuration and control of the system. New wavefront sensor camera models and DM models have been integrated with the system, increasing the number of possible hardware configurations available, and a fully open-source AO system is now a reality, including drivers necessary for commercial cameras and DMs. The computational performance of DARC makes it suitable for ELT scale systems when implemented on suitable hardware. We present tests made on different hardware platforms, along with the strategies taken to optimise DARC for these systems.
Research and Realization of the HJ-1C Real-time Software Frame Synchronization Algorithm
Hou Yang-shuan
2014-06-01
Full Text Available Conventional software frame synchronization methods are inefficient in processing huge continuous data without synchronization words. To improve the processing speed, a real-time synchronization algorithm is proposed based on reverse searching. Satellite data are grouped and searched in the reverse direction to avoid searching for synchronization words in huge continuous invalid data; thus, the frame synchronization speed is improved enormously. The fastest processing speed is up to 15445.9 Mbps when HJ-1C data are tested. This method is presently applied to the HJ-1C quick-look system in remote sensing satellite ground stations.
Hierarchical Search Motion Estimation Algorithms for Real-time Video Coding
1998-01-01
Data fetching and memory management are two factors as important as computation complexity in Motion Estimation(ME) implementation. In this paper, a new Large-scale Sampling Hierarchical Search motion estimation algorithm(LSHS) is proposed. The LSHS is suitable for real-time video coding with low computational complexity, reduced data fetching and simple memory access. The experiment results indicate the average decoding PSNR with LSHS is only about 0.2dB lower than that with Full Search (FS) scheme.
Performance of QoS-based multicast routing algorithms for real-time communication
Verma, Sanjeev; Pankaj, Rajesh K.; Leon-Garcia, Alberto
1997-10-01
In recent years, there has been a lot of interest in providing real-time multimedia services like digital audio and video over packet-switched networks such as Internet and ATM. These services require certain quality of service (QoS) from the network. The routing algorithm should take QoS factor for an application into account while selecting the most suitable route for the application. In this paper, we introduce a new routing metric and use it with two different heuristics to compute the multicast tree for guaranteed QoS applications that need firm end-to-end delay bound. We then compare the performance of our algorithms with the other proposed QoS-based routing algorithms. Simulations were run over a number of random networks to measure the performance of different algorithms. We studied routing algorithms along with resource reservation and admission control to measure the call throughput over a number of random networks. Simulation results show that our algorithms give a much better performance in terms of call throughput over other proposed schemes like QOSPF.
VLSI implementation of a template subtraction algorithm for real-time stimulus artifact rejection.
Limnuson, Kanokwan; Lu, Hui; Chiel, Hillel J; Mohseni, Pedram
2010-01-01
In this paper, we present very-large-scale integrated (VLSI) implementation of a template subtraction algorithm for stimulus artifact rejection (SAR) in real time with applicability to closed-loop neuroprostheses. The SAR algorithm is based upon an infinite impulse response (IIR) temporal filtering technique, which can be efficiently implemented in VLSI with reduced power consumption and silicon area. We demonstrate that initialization of the memory within the system architecture using the first recorded stimulus artifact significantly decreases system response time as compared to the case without memory initialization. Two sets of pre-recorded neural data from an Aplysia californica are used to simulate the functionality of the proposed VLSI architecture in AMS 0.35 microm complementary metal-oxide-semiconductor (CMOS) technology. Depending upon the reproducibility in the shape of stimulus artifacts in vivo, the system eliminates virtually all artifacts in real time and recovers the extracellular neural activity with microW-level power consumption from 1.5 V.
Real-time intelligent pattern recognition algorithm for surface EMG signals
Jahed Mehran
2007-12-01
Full Text Available Abstract Background Electromyography (EMG is the study of muscle function through the inquiry of electrical signals that the muscles emanate. EMG signals collected from the surface of the skin (Surface Electromyogram: sEMG can be used in different applications such as recognizing musculoskeletal neural based patterns intercepted for hand prosthesis movements. Current systems designed for controlling the prosthetic hands either have limited functions or can only be used to perform simple movements or use excessive amount of electrodes in order to achieve acceptable results. In an attempt to overcome these problems we have proposed an intelligent system to recognize hand movements and have provided a user assessment routine to evaluate the correctness of executed movements. Methods We propose to use an intelligent approach based on adaptive neuro-fuzzy inference system (ANFIS integrated with a real-time learning scheme to identify hand motion commands. For this purpose and to consider the effect of user evaluation on recognizing hand movements, vision feedback is applied to increase the capability of our system. By using this scheme the user may assess the correctness of the performed hand movement. In this work a hybrid method for training fuzzy system, consisting of back-propagation (BP and least mean square (LMS is utilized. Also in order to optimize the number of fuzzy rules, a subtractive clustering algorithm has been developed. To design an effective system, we consider a conventional scheme of EMG pattern recognition system. To design this system we propose to use two different sets of EMG features, namely time domain (TD and time-frequency representation (TFR. Also in order to decrease the undesirable effects of the dimension of these feature sets, principle component analysis (PCA is utilized. Results In this study, the myoelectric signals considered for classification consists of six unique hand movements. Features chosen for EMG signal
Zhang, Chenxin; Öwall, Viktor
2016-01-01
This book focuses on domain-specific heterogeneous reconfigurable architectures, demonstrating for readers a computing platform which is flexible enough to support multiple standards, multiple modes, and multiple algorithms. The content is multi-disciplinary, covering areas of wireless communication, computing architecture, and circuit design. The platform described provides real-time processing capability with reasonable implementation cost, achieving balanced trade-offs among flexibility, performance, and hardware costs. The authors discuss efficient design methods for wireless communication processing platforms, from both an algorithm and architecture design perspective. Coverage also includes computing platforms for different wireless technologies and standards, including MIMO, OFDM, Massive MIMO, DVB, WLAN, LTE/LTE-A, and 5G. •Discusses reconfigurable architectures, including hardware building blocks such as processing elements, memory sub-systems, Network-on-Chip (NoC), and dynamic hardware reconfigur...
A heuristic path-estimating algorithm for large-scale real-time traffic information calculating
2008-01-01
As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.
Minsker, B. S.; Zimmer, A. L.; Ostfeld, A.; Schmidt, A.
2014-12-01
Enabling real-time decision support, particularly under conditions of uncertainty, requires computationally efficient algorithms that can rapidly generate recommendations. In this paper, a suite of model predictive control (MPC) genetic algorithms are developed and tested offline to explore their value for reducing CSOs during real-time use in a deep-tunnel sewer system. MPC approaches include the micro-GA, the probability-based compact GA, and domain-specific GA methods that reduce the number of decision variable values analyzed within the sewer hydraulic model, thus reducing algorithm search space. Minimum fitness and constraint values achieved by all GA approaches, as well as computational times required to reach the minimum values, are compared to large population sizes with long convergence times. Optimization results for a subset of the Chicago combined sewer system indicate that genetic algorithm variations with coarse decision variable representation, eventually transitioning to the entire range of decision variable values, are most efficient at addressing the CSO control problem. Although diversity-enhancing micro-GAs evaluate a larger search space and exhibit shorter convergence times, these representations do not reach minimum fitness and constraint values. The domain-specific GAs prove to be the most efficient and are used to test CSO sensitivity to energy costs, CSO penalties, and pressurization constraint values. The results show that CSO volumes are highly dependent on the tunnel pressurization constraint, with reductions of 13% to 77% possible with less conservative operational strategies. Because current management practices may not account for varying costs at CSO locations and electricity rate changes in the summer and winter, the sensitivity of the results is evaluated for variable seasonal and diurnal CSO penalty costs and electricity-related system maintenance costs, as well as different sluice gate constraint levels. These findings indicate
An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU.
Xu, Hailong; Cui, Xiaowei; Lu, Mingquan
2016-03-11
Nowadays, software-defined radio (SDR) has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS) adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU) are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP) and Space-Frequency Adaptive Processing (SFAP) are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications.
An SDR-Based Real-Time Testbed for GNSS Adaptive Array Anti-Jamming Algorithms Accelerated by GPU
Hailong Xu
2016-03-01
Full Text Available Nowadays, software-defined radio (SDR has become a common approach to evaluate new algorithms. However, in the field of Global Navigation Satellite System (GNSS adaptive array anti-jamming, previous work has been limited due to the high computational power demanded by adaptive algorithms, and often lack flexibility and configurability. In this paper, the design and implementation of an SDR-based real-time testbed for GNSS adaptive array anti-jamming accelerated by a Graphics Processing Unit (GPU are documented. This testbed highlights itself as a feature-rich and extendible platform with great flexibility and configurability, as well as high computational performance. Both Space-Time Adaptive Processing (STAP and Space-Frequency Adaptive Processing (SFAP are implemented with a wide range of parameters. Raw data from as many as eight antenna elements can be processed in real-time in either an adaptive nulling or beamforming mode. To fully take advantage of the parallelism resource provided by the GPU, a batched method in programming is proposed. Tests and experiments are conducted to evaluate both the computational and anti-jamming performance. This platform can be used for research and prototyping, as well as a real product in certain applications.
A Backward Recovery Mechanism in Preemptive Utility Accrual Real Time Scheduling Algorithm
Idawaty Ahmad
2010-01-01
Full Text Available Problem statement: This study proposed a robust algorithm named as Backward Recovery Preemptive Utility Accrual Scheduling (BRPUAS algorithm that implements the Backward Recovery (BR mechanism as a fault recovery solution under the existing utility accrual scheduling environment. The problem identified in the TUF/UA scheduling domain is that the existing algorithms only considers the Abortion Recovery (AR as their fault recovery solution in which all faulty tasks are simply aborted to nullify the erroneous effect. The decision to immediately abort the affected tasks is inefficient because aborted tasks produce zero utility causes the system to accrue lower utility. Approach: The proposed BRPUAS algorithm enabled the re-execution of the affected tasks rather than abortion to reduce the number of aborted task in the existing algorithm known as Abortion Recovery Preemptive Utility Accrual Scheduling (ARPUAS algorithm that employed the AR mechanism. The BRPUAS ensure the correctness of the executed tasks in the best effort basis in such a way that the infeasible tasks are aborted and produced zero utility, while the feasible tasks are re-executed to produce positive utility and consequently maximized the total accrued utility to the system. The performances of these algorithms are measured by using discrete event simulation. Results: The proposed BRPUAS algorithm achieved higher accrued utility compared to ARPUAS for the entire load range. Conclusion: Simulation results revealed that the BR mechanism is more efficient than the existing AR mechanism, producing higher accrued utility ratio and less abortion ratio making it more reliable and efficient for adaptive real time application domain.
A Study of "Churn" in Tweets and Real-Time Search Queries (Extended Version)
Lin, Jimmy
2012-01-01
The real-time nature of Twitter means that term distributions in tweets and in search queries change rapidly: the most frequent terms in one hour may look very different from those in the next. Informally, we call this phenomenon "churn". Our interest in analyzing churn stems from the perspective of real-time search. Nearly all ranking functions, machine-learned or otherwise, depend on term statistics such as term frequency, document frequency, as well as query frequencies. In the real-time context, how do we compute these statistics, considering that the underlying distributions change rapidly? In this paper, we present an analysis of tweet and query churn on Twitter, as a first step to answering this question. Analyses reveal interesting insights on the temporal dynamics of term distributions on Twitter and hold implications for the design of search systems.
何建军; 任震; 黄雯莹; 周宏; 林涛
1999-01-01
With a complex wavelet function, a new real-time recursive algorithm of wavelet transform (WT) is analyzed in detail. Compared with the existing recursive algorithm in two directions, the computing time is greatly redueed in response to faults signals in power systems, and the same recursive algorithm can be generalized to other wavelet functions. With the phases and magnitudes of complex WT coefficients under the fast recursive algorithm, a method to detect faults signals of power systems is presented. Lastly, the analyzing results of some signals show that it is effective and practical for the complex wavelet and its real-time recursive algorithm to detect faults of power systems.
Use of NTRIP for Optimizing the Decoding Algorithm for Real-Time Data Streams
Zhanke He
2014-10-01
Full Text Available As a network transmission protocol, Networked Transport of RTCM via Internet Protocol (NTRIP is widely used in GPS and Global Orbiting Navigational Satellite System (GLONASS Augmentation systems, such as Continuous Operational Reference System (CORS, Wide Area Augmentation System (WAAS and Satellite Based Augmentation Systems (SBAS. With the deployment of BeiDou Navigation Satellite system(BDS to serve the Asia-Pacific region, there are increasing needs for ground monitoring of the BeiDou Navigation Satellite system and the development of the high-precision real-time BeiDou products. This paper aims to optimize the decoding algorithm of NTRIP Client data streams and the user authentication strategies of the NTRIP Caster based on NTRIP. The proposed method greatly enhances the handling efficiency and significantly reduces the data transmission delay compared with the Federal Agency for Cartography and Geodesy (BKG NTRIP. Meanwhile, a transcoding method is proposed to facilitate the data transformation from the BINary EXchange (BINEX format to the RTCM format. The transformation scheme thus solves the problem of handing real-time data streams from Trimble receivers in the BeiDou Navigation Satellite System indigenously developed by China.
Use of NTRIP for Optimizing the Decoding Algorithm for Real-Time Data Streams
He, Zhanke; Tang, Wenda; Yang, Xuhai; Wang, Liming; Liu, Jihua
2014-01-01
As a network transmission protocol, Networked Transport of RTCM via Internet Protocol (NTRIP) is widely used in GPS and Global Orbiting Navigational Satellite System (GLONASS) Augmentation systems, such as Continuous Operational Reference System (CORS), Wide Area Augmentation System (WAAS) and Satellite Based Augmentation Systems (SBAS). With the deployment of BeiDou Navigation Satellite system (BDS) to serve the Asia-Pacific region, there are increasing needs for ground monitoring of the BeiDou Navigation Satellite system and the development of the high-precision real-time BeiDou products. This paper aims to optimize the decoding algorithm of NTRIP Client data streams and the user authentication strategies of the NTRIP Caster based on NTRIP. The proposed method greatly enhances the handling efficiency and significantly reduces the data transmission delay compared with the Federal Agency for Cartography and Geodesy (BKG) NTRIP. Meanwhile, a transcoding method is proposed to facilitate the data transformation from the BINary EXchange (BINEX) format to the RTCM format. The transformation scheme thus solves the problem of handing real-time data streams from Trimble receivers in the BeiDou Navigation Satellite System indigenously developed by China. PMID:25310474
Real-time implementation of camera positioning algorithm based on FPGA & SOPC
Yang, Mingcao; Qiu, Yuehong
2014-09-01
In recent years, with the development of positioning algorithm and FPGA, to achieve the camera positioning based on real-time implementation, rapidity, accuracy of FPGA has become a possibility by way of in-depth study of embedded hardware and dual camera positioning system, this thesis set up an infrared optical positioning system based on FPGA and SOPC system, which enables real-time positioning to mark points in space. Thesis completion include: (1) uses a CMOS sensor to extract the pixel of three objects with total feet, implemented through FPGA hardware driver, visible-light LED, used here as the target point of the instrument. (2) prior to extraction of the feature point coordinates, the image needs to be filtered to avoid affecting the physical properties of the system to bring the platform, where the median filtering. (3) Coordinate signs point to FPGA hardware circuit extraction, a new iterative threshold selection method for segmentation of images. Binary image is then segmented image tags, which calculates the coordinates of the feature points of the needle through the center of gravity method. (4) direct linear transformation (DLT) and extreme constraints method is applied to three-dimensional reconstruction of the plane array CMOS system space coordinates. using SOPC system on a chip here, taking advantage of dual-core computing systems, which let match and coordinate operations separately, thus increase processing speed.
Improved radar data processing algorithms for quantitative rainfall estimation in real time.
Krämer, S; Verworn, H R
2009-01-01
This paper describes a new methodology to process C-band radar data for direct use as rainfall input to hydrologic and hydrodynamic models and in real time control of urban drainage systems. In contrast to the adjustment of radar data with the help of rain gauges, the new approach accounts for the microphysical properties of current rainfall. In a first step radar data are corrected for attenuation. This phenomenon has been identified as the main cause for the general underestimation of radar rainfall. Systematic variation of the attenuation coefficients within predefined bounds allows robust reflectivity profiling. Secondly, event specific R-Z relations are applied to the corrected radar reflectivity data in order to generate quantitative reliable radar rainfall estimates. The results of the methodology are validated by a network of 37 rain gauges located in the Emscher and Lippe river basins. Finally, the relevance of the correction methodology for radar rainfall forecasts is demonstrated. It has become clearly obvious, that the new methodology significantly improves the radar rainfall estimation and rainfall forecasts. The algorithms are applicable in real time.
Internet Data Distribution – extending real-time data sharing throughout the Americas
T. Yoksas
2006-01-01
Full Text Available The Unidata Program Center (Unidata of the University Corporation of Atmospheric Research (UCAR is involved in three international collaborations whose goals are extension of real-time data delivery-to and sharing-of locally held datasets-by educational institutions throughout the Americas. These efforts are based on the use of Unidata's Internet Data Distribution (IDD system which is built on top of its proven Local Data Manager Version 6 (LDM-6 technology. The Unidata IDD is an event-driven network of cooperating Unidata LDM servers that distributes discipline-neutral data products in near real-time over wide-area networks. The IDD, a collaboration of over 150 mostly North American institutions of higher education, has been the primary source of real-time atmospheric science data for the US university community for over a decade,. In addition to providing a highly reliable mechanism for delivering real-time data, the IDD allows users to easily share locally held datasets.
Real-time infrared gas detection based on an adaptive Savitzky-Golay algorithm
Li, Jingsong; Deng, Hao; Li, Pengfei; Yu, Benli
2015-08-01
Based on the Savitzky-Golay filter, we have developed in the present study a simple but robust method for real-time processing of tunable diode laser absorption spectroscopy (TDLAS) signals. Our method was developed to resolve the blindness of selecting the input filter parameters and to mitigate potential signal distortion induced in digital signal processing. Application of the developed adaptive Savitzky-Golay filter algorithm to the simulated and experimentally observed signals and comparison with the wavelet-based de-noising technique indicate that the newly developed method is effective in obtaining high-quality TDLAS data for a wide variety of applications including atmospheric environmental monitoring and industrial processing control.
Parallel algorithm for real-time contouring from grid DEM on modern GPUs
无
2010-01-01
A real-time algorithm for constructing contour maps from grid DEM data is pre-sented.It runs completely within the programmable 3D visualization pipeline.The interpolation is paralleled by rasterizer units in the graphics card,and contour line extraction is paralleled by pixel shader.During each frame of the rendering,we first make an elevation gradient map out of original terrain vertex data,then figure out the final contour lines with image-space processing,and directly blend the results on the original scene to obtain a final scene with contour map using alpha-blending.We implement this method in our global 3D-digitalearth system with Direct3D?9.0c API and tested on some consumer level PC platforms.For arbitrary scene with certain LOD level,the process takes less than 10 ms,giving topologically correct,anti-aliased contour lines.
FPGA-based real-time phase measuring profilometry algorithm design and implementation
Zhan, Guomin; Tang, Hongwei; Zhong, Kai; Li, Zhongwei; Shi, Yusheng
2016-11-01
Phase measuring profilometry (PMP) has been widely used in many fields, like Computer Aided Verification (CAV), Flexible Manufacturing System (FMS) et al. High frame-rate (HFR) real-time vision-based feedback control will be a common demands in near future. However, the instruction time delay in the computer caused by numerous repetitive operations greatly limit the efficiency of data processing. FPGA has the advantages of pipeline architecture and parallel execution, and it fit for handling PMP algorithm. In this paper, we design a fully pipelined hardware architecture for PMP. The functions of hardware architecture includes rectification, phase calculation, phase shifting, and stereo matching. The experiment verified the performance of this method, and the factors that may influence the computation accuracy was analyzed.
A new real-time algorithm for off-road terrain estimation using laser data
QIU Quan; YANG TangWen; HAN JianDa
2009-01-01
Gaussian mixture algorithm (GMA) is an effective approach for off-road terrain estimation,but still suffers from some difficulties in practical applications,such as complex calculation and object abstraction.In this paper,GMA is modified to improve its real-time performance and to provide it with a potential ability of obstacle detection.First,a selection window is designed based on the dominant-ellipse-principle to limit the probability distribution area of each measurement point,therefore avoiding the calculation on the cells outside the dominant ellipse.Second,a clustering approach is proposed in order to distinguish objects efficiently and decrease the operation area of one laser scan.Third,a virtual point vector is introduced to further reduce the computational load of the mean square error matrix.The modified GMA is experimented on a tracked mobile robot,and its improved performance is shown in comparison to the original GMA.
A real-time misalignment correction algorithm for stereoscopic 3D cameras
Pekkucuksen, Ibrahim E.; Batur, Aziz Umit; Zhang, Buyue
2012-03-01
Camera calibration is an important problem for stereo 3-D cameras since the misalignment between the two views can lead to vertical disparities that significantly degrade 3-D viewing quality. Offline calibration during manufacturing is not always an option especially for mass produced cameras due to cost. In addition, even if one-time calibration is performed during manufacturing, its accuracy cannot be maintained indefinitely because environmental factors can lead to changes in camera hardware. In this paper, we propose a real-time stereo calibration solution that runs inside a consumer camera and continuously estimates and corrects for the misalignment between the stereo cameras. Our algorithm works by processing images of natural scenes and does not require the use of special calibration charts. The algorithm first estimates the disparity in horizontal and vertical directions between the corresponding blocks from stereo images. Then, this initial estimate is refined with two dimensional search using smaller sub-blocks. The displacement data and block coordinates are fed to a modified affine transformation model and outliers are discarded to keep the modeling error low. Finally, the estimated affine parameters are split by half and misalignment correction is applied to each view accordingly. The proposed algorithm significantly reduces the misalignment between stereo frames and enables a more comfortable 3-D viewing experience.
A Fast Density-Based Clustering Algorithm for Real-Time Internet of Things Stream
Amineh Amini
2014-01-01
Full Text Available Data streams are continuously generated over time from Internet of Things (IoT devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets.
A fast density-based clustering algorithm for real-time Internet of Things stream.
Amini, Amineh; Saboohi, Hadi; Wah, Teh Ying; Herawan, Tutut
2014-01-01
Data streams are continuously generated over time from Internet of Things (IoT) devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets.
Gkaitatzis, Stamatios; The ATLAS collaboration
2016-01-01
In this paper the performance of the 2D pixel clustering algorithm developed for the Input Mezzanine card of the ATLAS Fast TracKer system is presented. Fast TracKer is an approved ATLAS upgrade that has the goal to provide a complete list of tracks to the ATLAS High Level Trigger for each level-1 accepted event, at up to 100 kHz event rate with a very small latency, in the order of 100 µs. The Input Mezzanine card is the input stage of the Fast TracKer system. Its role is to receive data from the silicon detector and perform real time clustering, thus to reduce the amount of data propagated to the subsequent processing levels with minimal information loss. We focus on the most challenging component on the Input Mezzanine card, the 2D clustering algorithm executed on the pixel data. We compare two different implementations of the algorithm. The first is one called the ideal one which searches clusters of pixels in the whole silicon module at once and calculates the cluster centroids exploiting the whole avai...
Gkaitatzis, Stamatios; The ATLAS collaboration; Annovi, Alberto; Kordas, Kostantinos
2016-01-01
In this paper the performance of the 2D pixel clustering algorithm developed for the Input Mezzanine card of the ATLAS Fast TracKer system is presented. Fast TracKer is an approved ATLAS upgrade that has the goal to provide a complete list of tracks to the ATLAS High Level Trigger for each level-1 accepted event, at up to 100 kHz event rate with a very small latency, in the order of 100µs. The Input Mezzanine card is the input stage of the Fast TracKer system. Its role is to receive data from the silicon detector and perform real time clustering, thus to reduce the amount of data propagated to the subsequent processing levels with minimal information loss. We focus on the most challenging component on the Input Mezzanine card, the 2D clustering algorithm executed on the pixel data. We compare two different implementations of the algorithm. The first is one called the ideal one which searches clusters of pixels in the whole silicon module at once and calculates the cluster centroids exploiting the whole avail...
Smart sensing to drive real-time loads scheduling algorithm in a domotic architecture
Santamaria, Amilcare Francesco; Raimondo, Pierfrancesco; De Rango, Floriano; Vaccaro, Andrea
2014-05-01
Nowadays the focus on power consumption represent a very important factor regarding the reduction of power consumption with correlated costs and the environmental sustainability problems. Automatic control load based on power consumption and use cycle represents the optimal solution to costs restraint. The purpose of these systems is to modulate the power request of electricity avoiding an unorganized work of the loads, using intelligent techniques to manage them based on real time scheduling algorithms. The goal is to coordinate a set of electrical loads to optimize energy costs and consumptions based on the stipulated contract terms. The proposed algorithm use two new main notions: priority driven loads and smart scheduling loads. The priority driven loads can be turned off (stand by) according to a priority policy established by the user if the consumption exceed a defined threshold, on the contrary smart scheduling loads are scheduled in a particular way to don't stop their Life Cycle (LC) safeguarding the devices functions or allowing the user to freely use the devices without the risk of exceeding the power threshold. The algorithm, using these two kind of notions and taking into account user requirements, manages loads activation and deactivation allowing the completion their operation cycle without exceeding the consumption threshold in an off-peak time range according to the electricity fare. This kind of logic is inspired by industrial lean manufacturing which focus is to minimize any kind of power waste optimizing the available resources.
Dong Zhang
2014-02-01
Full Text Available This paper presents a new profile shape matching stereovision algorithm that is designed to extract 3D information in real time. This algorithm obtains 3D information by matching profile intensity shapes of each corresponding row of the stereo image pair. It detects the corresponding matching patterns of the intensity profile rather than the intensity values of individual pixels or pixels in a small neighbourhood. This approach reduces the effect of the intensity and colour variations caused by lighting differences. As with all real-time vision algorithms, there is always a trade-off between accuracy and processing speed. This algorithm achieves a balance between the two to produce accurate results for real-time applications. To demonstrate its performance, the proposed algorithm is tested for human pose and hand gesture recognition to control a smart phone and an entertainment system.
Extending the range of real time density matrix renormalization group simulations
Kennes, D. M.; Karrasch, C.
2016-03-01
We discuss a few simple modifications to time-dependent density matrix renormalization group (DMRG) algorithms which allow to access larger time scales. We specifically aim at beginners and present practical aspects of how to implement these modifications within any standard matrix product state (MPS) based formulation of the method. Most importantly, we show how to 'combine' the Schrödinger and Heisenberg time evolutions of arbitrary pure states | ψ > and operators A in the evaluation of ψ(t) = . This includes quantum quenches. The generalization to (non-)thermal mixed state dynamics ρ(t) =Tr [ ρA(t) ] induced by an initial density matrix ρ is straightforward. In the context of linear response (ground state or finite temperature T > 0) correlation functions, one can extend the simulation time by a factor of two by 'exploiting time translation invariance', which is efficiently implementable within MPS DMRG. We present a simple analytic argument for why a recently-introduced disentangler succeeds in reducing the effort of time-dependent simulations at T > 0. Finally, we advocate the python programming language as an elegant option for beginners to set up a DMRG code.
Development of a Near-Real Time Hail Damage Swath Identification Algorithm for Vegetation
Bell, Jordan R.; Molthan, Andrew L.; Schultz, Lori A.; McGrath, Kevin M.; Burks, Jason E.
2015-01-01
The Midwest is home to one of the world's largest agricultural growing regions. Between the time period of late May through early September, and with irrigation and seasonal rainfall these crops are able to reach their full maturity. Using moderate to high resolution remote sensors, the monitoring of the vegetation can be achieved using the red and near-infrared wavelengths. These wavelengths allow for the calculation of vegetation indices, such as Normalized Difference Vegetation Index (NDVI). The vegetation growth and greenness, in this region, grows and evolves uniformly as the growing season progresses. However one of the biggest threats to Midwest vegetation during the time period is thunderstorms that bring large hail and damaging winds. Hail and wind damage to crops can be very expensive to crop growers and, damage can be spread over long swaths associated with the tracks of the damaging storms. Damage to the vegetation can be apparent in remotely sensed imagery and is visible from space after storms slightly damage the crops, allowing for changes to occur slowly over time as the crops wilt or more readily apparent if the storms strip material from the crops or destroy them completely. Previous work on identifying these hail damage swaths used manual interpretation by the way of moderate and higher resolution satellite imagery. With the development of an automated and near-real time hail swath damage identification algorithm, detection can be improved, and more damage indicators be created in a faster and more efficient way. The automated detection of hail damage swaths will examine short-term, large changes in the vegetation by differencing near-real time eight day NDVI composites and comparing them to post storm imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard Terra and Aqua and Visible Infrared Imaging Radiometer Suite (VIIRS) aboard Suomi NPP. In addition land surface temperatures from these instruments will be examined as
An adaptive embedded architecture for real-time Particle Image Velocimetry algorithms
Aubert, Alain; Fresse, Virginie
2008-01-01
Particle Image Velocimetry (PIV) is a method of im-aging and analysing fields of flows. The PIV tech-niques compute and display all the motion vectors of the field in a resulting image. Speeds more than thou-sand vectors per second can be required, each speed being environment-dependent. Essence of this work is to propose an adaptive FPGA-based system for real-time PIV algorithms. The proposed structure is ge-neric so that this unique structure can be re-used for any PIV applications that uses the cross-correlation technique. The major structure remains unchanged, adaptations only concern the number of processing operations. The required speed (corresponding to the number of vector per second) is obtained thanks to a parallel processing strategy. The image processing designer duplicates the processing modules to distrib-ute the operations. The result is a FPGA-based archi-tecture, which is easily adapted to algorithm specifica-tions without any hardware requirement. The design flow is fast and reliable.
Real-time planar flow velocity measurements using an optical flow algorithm implemented on GPU
Gautier, N
2013-01-01
This paper presents a high speed implementation of an optical flow algorithm which computes planar velocity fields in an experimental flow. Real-time computation of the flow velocity field allows the experimentalist to have instantaneous access to quantitative features of the flow. This can be very useful in many situations: fast evaluation of the performances and characteristics of a new setup, design optimization, easier and faster parametric studies, etc. It can also be a valuable measurement tool for closed-loop flow control experiments where fast estimation of the state of the flow is needed. The algorithm is implemented on a Graphics Processing Unit (GPU). The accuracy of the computation is shown. Computation speed and scalability are highlighted along with guidelines for further improvements. The system architecture is flexible, scalable and can be adapted on the fly in order to process higher resolutions or achieve higher precision. The set-up is applied on a Backward-Facing Step (BFS) flow in a hydro...
Davis, M. W.
1984-01-01
A Real-Time Self-Adaptive (RTSA) active vibration controller was used as the framework in developing a computer program for a generic controller that can be used to alleviate helicopter vibration. Based upon on-line identification of system parameters, the generic controller minimizes vibration in the fuselage by closed-loop implementation of higher harmonic control in the main rotor system. The new generic controller incorporates a set of improved algorithms that gives the capability to readily define many different configurations by selecting one of three different controller types (deterministic, cautious, and dual), one of two linear system models (local and global), and one or more of several methods of applying limits on control inputs (external and/or internal limits on higher harmonic pitch amplitude and rate). A helicopter rotor simulation analysis was used to evaluate the algorithms associated with the alternative controller types as applied to the four-bladed H-34 rotor mounted on the NASA Ames Rotor Test Apparatus (RTA) which represents the fuselage. After proper tuning all three controllers provide more effective vibration reduction and converge more quickly and smoothly with smaller control inputs than the initial RTSA controller (deterministic with external pitch-rate limiting). It is demonstrated that internal limiting of the control inputs a significantly improves the overall performance of the deterministic controller.
A Joint-optimized Real-time Target Detection Algorithm for Passive Radar
Zhao Yong-ke
2015-01-01
Full Text Available Passive radar exploits an external illuminator signal to detect targets. It has the advantages of silence, anti-interference, and counter-stealth ability. In most cases, direct and multipath clutters should be suppressed first. Then coherent detection can be made by performing a cross-ambiguity function of the remaining target echoes and the reference signal. However, under a wide-band signal, a long-integration time, or multi-beam circumstances, a large number of computations and amount of memory is required for normal processing. This paper expresses the mathematical relationships of clutter suppression algorithms based on the Minimum Mean Square Error (MMSE principle and coherent detection algorithms based on the cross-ambiguity function. Herein, a joint-optimize and processing method is presented. This method reduces the number of computations and amount of memory required, is easy to implement on GPU devices such as CUDA, and will be useful for engineering applications. Its high-efficiency and real-time properties are validated in the experimental results.
Pallab Banerjee; Talat Zabin; ShwetaKumai; Pushpa Kumari
2015-01-01
Round Robin Scheduling algorithm is designed especially for Real Time Operating system (RTOS). It is a preemptive CPU scheduling algorithm which switches between the processes when static time Quantum expires .Existing Round Robin CPU scheduling algorithm cannot be implemented in real time operating system due to their high context switch rates, large waiting time, large response time, large turnaround time and less throughput . In this paper a new algorithm is presented called Best Performan...
Hwang, J Y; Kang, J M; Jang, Y W; Kim, H
2004-01-01
Novel algorithm and real-time ambulatory monitoring system for fall detection in elderly people is described. Our system is comprised of accelerometer, tilt sensor and gyroscope. For real-time monitoring, we used Bluetooth. Accelerometer measures kinetic force, tilt sensor and gyroscope estimates body posture. Also, we suggested algorithm using signals which obtained from the system attached to the chest for fall detection. To evaluate our system and algorithm, we experimented on three people aged over 26 years. The experiment of four cases such as forward fall, backward fall, side fall and sit-stand was repeated ten times and the experiment in daily life activity was performed one time to each subject. These experiments showed that our system and algorithm could distinguish between falling and daily life activity. Moreover, the accuracy of fall detection is 96.7%. Our system is especially adapted for long-time and real-time ambulatory monitoring of elderly people in emergency situation.
WANG Pei-dong; WEI Zhen-hua
2008-01-01
To make the on-board computer system more dependable and real-time in a satellite, an algorithm of the fault-tolerant scheduling in the on-board computer system with high priority recovery is proposed in this paper. This algorithm can schedule the on-board fault-tolerant tasks in real time. Due to the use of dependability cost, the overhead of scheduling the fault-tolerant tasks can be reduced. The mechanism of the high priority recovery will improve the response to recovery tasks. The fault-tolerant scheduling model is presented simulation results validate the correctness and feasibility of the proposed algorithm.
Real-time Walking Pattern Generation for a Biped Robot with Hybrid CPG-ZMP Algorithm
Bin He
2014-10-01
Full Text Available Biped robots have better mobility than conventional wheeled robots. The bio-inspired method based on a central pattern generator (CPG can be used to control biped robot walking in a manner like human beings. However, to achieve stable locomotion, it is difficult to modulate the parameters for the neural networks to coordinate every degree of freedom of the walking robot. The zero moment point (ZMP method is very popular for the stability control of biped robot walking. However, the reference trajectories have low energy efficiency, lack naturalness and need significant offline calculation. This paper presents a new method for biped real-time walking generation using a hybrid CPG-ZMP control algorithm. The method can realize a stable walking pattern by combining the ZMP criterion with rhythmic motion control. The CPG component is designed to generate the desired motion for each robot joint, which is modulated by phase resetting according to foot contact information. By introducing the ZMP location, the activity of the CPG output signal is adjusted to coordinate the limbs’ motion and allow the robot to maintain balance during the process of locomotion. The numerical simulation results show that, compared with the CPG method, the new hybrid CPG-ZMP algorithm can enhance the robustness of the CPG parameters and improve the stability of the robot. In addition, the proposed algorithm is more energy efficient than the ZMP method. The results also demonstrate that the control system can generate an adaptive walking pattern through interactions between the robot, the CPG and the environment.
Extended neural network-based scheme for real-time force tracking with magnetorheological dampers
Weber, Felix; Bhowmik, Subrata; Høgsberg, Jan Becker
2014-01-01
This paper validates numerically and experimentally a new neural network-based real-time force tracking scheme for magnetorheological (MR) dampers on a five-storey shear frame with MR damper. The inverse model is trained with absolute values of measured velocity and force because the targeted...... current is a positive quantity. The validation shows accurate results except of small current spikes when the desired force is in the vicinity of the residual MR damper force. In the closed-loop, higher frequency components in the current are triggered by the transition of the actual MR damper force from...... the pre-yield to the post-yield region. A control-oriented approach is presented to compensate for these drawbacks. The resulting control force tracking scheme is validated for the emulation of viscous damping, clipped viscous damping with negative stiffness, and friction damping with negative stiffness...
A fast forward algorithm for real-time geosteering of azimuthal gamma-ray logging.
Qin, Zhen; Pan, Heping; Wang, Zhonghao; Wang, Bintao; Huang, Ke; Liu, Shaohua; Li, Gang; Amara Konaté, Ahmed; Fang, Sinan
2017-05-01
Geosteering is an effective method to increase the reservoir drilling rate in horizontal wells. Based on the features of an azimuthal gamma-ray logging tool and strata spatial location, a fast forward calculation method of azimuthal gamma-ray logging is deduced by using the natural gamma ray distribution equation in formation. The response characteristics of azimuthal gamma-ray logging while drilling in the layered formation models with different thickness and position are simulated and summarized by using the method. The result indicates that the method calculates quickly, and when the tool nears a boundary, the method can be used to identify the boundary and determine the distance from the logging tool to the boundary in time. Additionally, the formation parameters of the algorithm in the field can be determined after a simple method is proposed based on the information of an offset well. Therefore, the forward method can be used for geosteering in the field. A field example validates that the forward method can be used to determine the distance from the azimuthal gamma-ray logging tool to the boundary for geosteering in real-time.
A Brain-Machine Interface Operating with a Real-Time Spiking Neural Network Control Algorithm.
Dethier, Julie; Nuyujukian, Paul; Eliasmith, Chris; Stewart, Terry; Elassaad, Shauki A; Shenoy, Krishna V; Boahen, Kwabena
2011-01-01
Motor prostheses aim to restore function to disabled patients. Despite compelling proof of concept systems, barriers to clinical translation remain. One challenge is to develop a low-power, fully-implantable system that dissipates only minimal power so as not to damage tissue. To this end, we implemented a Kalman-filter based decoder via a spiking neural network (SNN) and tested it in brain-machine interface (BMI) experiments with a rhesus monkey. The Kalman filter was trained to predict the arm's velocity and mapped on to the SNN using the Neural Engineering Framework (NEF). A 2,000-neuron embedded Matlab SNN implementation runs in real-time and its closed-loop performance is quite comparable to that of the standard Kalman filter. The success of this closed-loop decoder holds promise for hardware SNN implementations of statistical signal processing algorithms on neuromorphic chips, which may offer power savings necessary to overcome a major obstacle to the successful clinical translation of neural motor prostheses.
A Real-Time Atrial Fibrillation Detection Algorithm Based on the Instantaneous State of Heart Rate.
Xiaolin Zhou
Full Text Available Atrial fibrillation (AF, the most frequent cause of cardioembolic stroke, is increasing in prevalence as the population ages, and presents with a broad spectrum of symptoms and severity. The early identification of AF is an essential part for preventing the possibility of blood clotting and stroke. In this work, a real-time algorithm is proposed for accurately screening AF episodes in electrocardiograms. This method adopts heart rate sequence, and it involves the application of symbolic dynamics and Shannon entropy. Using novel recursive algorithms, a low-computational complexity can be obtained. Four publicly-accessible sets of clinical data (Long-Term AF, MIT-BIH AF, MIT-BIH Arrhythmia, and MIT-BIH Normal Sinus Rhythm Databases were used for assessment. The first database was selected as a training set; the receiver operating characteristic (ROC curve was performed, and the best performance was achieved at the threshold of 0.639: the sensitivity (Se, specificity (Sp, positive predictive value (PPV and overall accuracy (ACC were 96.14%, 95.73%, 97.03% and 95.97%, respectively. The other three databases were used for independent testing. Using the obtained decision-making threshold (i.e., 0.639, for the second set, the obtained parameters were 97.37%, 98.44%, 97.89% and 97.99%, respectively; for the third database, these parameters were 97.83%, 87.41%, 47.67% and 88.51%, respectively; the Sp was 99.68% for the fourth set. The latest methods were also employed for comparison. Collectively, results presented in this study indicate that the combination of symbolic dynamics and Shannon entropy yields a potent AF detector, and suggest this method could be of practical use in both clinical and out-of-clinical settings.
Libing Wang
2014-01-01
Full Text Available In order to control the cascaded H-bridges (CHB converter with staircase modulation strategy in a real-time manner, a real-time and closed-loop control algorithm based on artificial neural network (ANN for three-phase CHB converter is proposed in this paper. It costs little computation time and memory. It has two steps. In the first step, hierarchical particle swarm optimizer with time-varying acceleration coefficient (HPSO-TVAC algorithm is employed to minimize the total harmonic distortion (THD and generate the optimal switching angles offline. In the second step, part of optimal switching angles are used to train an ANN and the well-designed ANN can generate optimal switching angles in a real-time manner. Compared with previous real-time algorithm, the proposed algorithm is suitable for a wider range of modulation index and results in a smaller THD and a lower calculation time. Furthermore, the well-designed ANN is embedded into a closed-loop control algorithm for CHB converter with variable direct voltage (DC sources. Simulation results demonstrate that the proposed closed-loop control algorithm is able to quickly stabilize load voltage and minimize the line current’s THD (<5% when subjecting the DC sources disturbance or load disturbance. In real design stage, a switching angle pulse generation scheme is proposed and experiment results verify its correctness.
Won, Jihye; Park, Kwan-Dong
2015-04-01
Real-time PPP-RTK positioning algorithms were developed for the purpose of getting precise coordinates of moving platforms. In this implementation, corrections for the satellite orbit and satellite clock were taken from the IGS-RTS products while the ionospheric delay was removed through ionosphere-free combination and the tropospheric delay was either taken care of using the Global Pressure and Temperature (GPT) model or estimated as a stochastic parameter. To improve the convergence speed, all the available GPS and GLONASS measurements were used and Extended Kalman Filter parameters were optimized. To validate our algorithms, we collected the GPS and GLONASS data from a geodetic-quality receiver installed on a roof of a moving vehicle in an open-sky environment and used IGS final products of satellite orbits and clock offsets. The horizontal positioning error got less than 10 cm within 5 minutes, and the error stayed below 10 cm even after the vehicle start moving. When the IGS-RTS product and the GPT model were used instead of the IGS precise product, the positioning accuracy of the moving vehicle was maintained at better than 20 cm once convergence was achieved at around 6 minutes.
A near real time MSG-SEVIRI based algorithm for gas flaring monitoring
Faruolo, Mariapia; Coviello, Irina; Filizzola, Carolina; Lacava, Teodosio; Pergola, Nicola; Tramutoli, Valerio
2015-04-01
In the last decades oil and gas industry has become responsible for important environmental issues. The gas flaring, one of the processes used to dispose of the natural gas associated with extracted crude oil, has been recognized as being potentially harmful to human health and the atmosphere. Efforts to empirically assess the environmental impacts of such phenomenon are frequently hampered by limited access to official information on flare locations and volumes, the heterogeneity in spatial and temporal sampling strategies and methods used to collect data. Consequently, there is a need to develop new methods of acquiring such information and remote sensing techniques seem the most viable option. In this paper, with reference to this problem, the potential of a satellite based technique for a near real time detection and characterization of hot spot sources was assessed. In detail, Medium Infrared (MIR) radiances acquired by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) scanner carried aboard the Meteosat Second Generation (MSG) satellite were processed following the Robust Satellite Techniques (RST) prescriptions. Such an algorithm, based on the processing of multi-year satellite images, co-located in the space-time domain, allows to timely identify statistically significant variations of the MIR signal, related to changes and/or malfunctions in the industrial process and responsible for the gas flaring blazes. Results achieved, referring to the flaring activity of the Centro Olio Val d'Agri (COVA), an oil/gas plant located in the South of Italy, will be described in detail and discussed in this paper.
Using FPGAs to Implement DSP Algorithms in Real Time for Gamma Spectroscopy Instruments
Bushart, B.
1999-08-31
Today's DSPs are capable of handling audio processing or even real time video processing; however, when the sample rate is equal to or exceeds the DSP instruction clock rate it becomes impossible to perform real time signal processing. The Savannah River Technology Center has developed a nearly all-digital radiation instrument that incorporates a single integer processor, as well as an FPGA.
LI; Zicheng; SUN; Yukun
2006-01-01
Considering the detection principle that "when load current is periodic current, the integral in a cycle for absolute value of load current subtracting fundamental active current is the least", harmonic current real-time detection methods for power active filter are proposed based on direct computation, simple iterative algorithm and optimal iterative algorithm. According to the direct computation method, the amplitude of the fundamental active current can be accurately calculated when load current is placed in stable state. The simple iterative algorithm and the optimal iterative algorithm provide an idea about judging the state of load current. On the basis of the direct computation method, the simple iterative algorithm, the optimal iterative algorithm and precise definition of the basic concepts such as the true amplitude of the fundamental active current when load current is placed in varying state, etc., the double linear construction idea is proposed in which the amplitude of the fundamental active current at the moment of the sample is accurately calculated by using the first linear construction and the condition which disposes the next sample is created by using the second linear construction. On the basis of the double linear construction idea, a harmonic current real-time detection method for power active filter is proposed based on the double linear construction algorithm. This method has the characteristics of small computing quantity, fine real-time performance, being capable of accurately calculating the amplitude of the fundamental active current and so on.
Muhammad Abdullah Awais
2016-04-01
Full Text Available Different memory allocation algorithms have been devised to organize memory efficiently in different timestamps according to the needs and scenario of usage yet there are issues and challenges of these allocators to provide full support for real time needs. Real time systems require memory on priority otherwise program may crash or may be unresponsive if demanded memory is not allocated with quick response. Besides the timing constraints, memory allocator algorithms must minimize the memory loss which comes in the form of fragmentation, the unusable memory in response to the memory allocation needs because memory is allocated in the form of blocks. Our focus would be to analyse traditional dynamic memory management algorithms with respect to their functionality, response time and efficiency to find out the issues and challenges with these allocators to sum up the knowledge to know the limitations of these algorithm which might reduce the performance of real time systems. This research paper will give a comparative analysis of some well known memory management techniques to highlight issues for real time systems and innovative techniques suitable for these applications will be argued.
The Research and Test of Fast Radio Burst Real-time Search Algorithm Based on GPU Acceleration
Wang, J.; Chen, M. Z.; Pei, X.; Wang, Z. Q.
2017-03-01
In order to satisfy the research needs of Nanshan 25 m radio telescope of Xinjiang Astronomical Observatory (XAO) and study the key technology of the planned QiTai radio Telescope (QTT), the receiver group of XAO studied the GPU (Graphics Processing Unit) based real-time FRB searching algorithm which developed from the original FRB searching algorithm based on CPU (Central Processing Unit), and built the FRB real-time searching system. The comparison of the GPU system and the CPU system shows that: on the basis of ensuring the accuracy of the search, the speed of the GPU accelerated algorithm is improved by 35-45 times compared with the CPU algorithm.
Daniels, M. D.; Graves, S. J.; Kerkez, B.; Chandrasekar, V.; Vernon, F.; Martin, C. L.; Maskey, M.; Keiser, K.; Dye, M. J.
2015-12-01
The Cloud-Hosted Real-time Data Services for the Geosciences (CHORDS) project was funded under the National Science Foundation's EarthCube initiative. CHORDS addresses the ever-increasing importance of real-time scientific data in the geosciences, particularly in mission critical scenarios, where informed decisions must be made rapidly. Access to constant streams of real-time data also allow many new transient phenomena in space-time to be observed, however, much of these streaming data are either completely inaccessible or only available to proprietary in-house tools or displays. Small research teams do not have the resources to develop tools for the broad dissemination of their unique real-time data and require an easy to use, scalable, cloud-based solution to facilitate this access. CHORDS will make these diverse streams of real-time data available to the broader geosciences community. This talk will highlight a recently developed CHORDS portal tools and processing systems which address some of the gaps in handling real-time data, particularly in the provisioning of data from the "long-tail" scientific community through a simple interface that is deployed in the cloud, is scalable and is able to be customized by research teams. A running portal, with operational data feeds from across the nation, will be presented. The processing within the CHORDS system will expose these real-time streams via standard services from the Open Geospatial Consortium (OGC) in a way that is simple and transparent to the data provider, while maximizing the usage of these investments. The ingestion of high velocity, high volume and diverse data has allowed the project to explore a NoSQL database implementation. Broad use of the CHORDS framework by geoscientists will help to facilitate adaptive experimentation, model assimilation and real-time hypothesis testing.
Development of a Near Real-Time Hail Damage Swath Identification Algorithm for Vegetation
Bell, Jordan R.; Molthan, Andrew L.; Schultz, Kori A.; McGrath, Kevin M.; Burks, Jason E.
2015-01-01
Every year in the Midwest and Great Plains, widespread greenness forms in conjunction with the latter part of the spring-summer growing season. This prevalent greenness forms as a result of the high concentration of agricultural areas having their crops reach their maturity before the fall harvest. This time of year also coincides with an enhanced hail frequency for the Great Plains (Cintineo et al. 2012). These severe thunderstorms can bring damaging winds and large hail that can result in damage to the surface vegetation. The spatial extent of the damage can relatively small concentrated area or be a vast swath of damage that is visible from space. These large areas of damage have been well documented over the years. In the late 1960s aerial photography was used to evaluate crop damage caused by hail. As satellite remote sensing technology has evolved, the identification of these hail damage streaks has increased. Satellites have made it possible to view these streaks in additional spectrums. Parker et al. (2005) documented two streaks using the Moderate Resolution Imaging Spectroradiometer (MODIS) that occurred in South Dakota. He noted the potential impact that these streaks had on the surface temperature and associated surface fluxes that are impacted by a change in temperature. Gallo et al. (2012) examined at the correlation between radar signatures and ground observations from storms that produced a hail damage swath in Central Iowa also using MODIS. Finally, Molthan et al. (2013) identified hail damage streaks through MODIS, Landsat-7, and SPOT observations of different resolutions for the development of a potential near-real time applications. The manual analysis of hail damage streaks in satellite imagery is both tedious and time consuming, and may be inconsistent from event to event. This study focuses on development of an objective and automatic algorithm to detect these areas of damage in a more efficient and timely manner. This study utilizes the
A real-time photo-realistic rendering algorithm of ocean color based on bio-optical model
Ma, Chunyong; Xu, Shu; Wang, Hongsong; Tian, Fenglin; Chen, Ge
2016-12-01
A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton, colored dissolved organic material (CDOM), inorganic suspended particle, etc., which have different contributions to absorption and scattering of light. We decompose the emergent light of the ocean surface into the reflected light from the sun and the sky, and the subsurface scattering light. We establish an ocean surface transmission model based on ocean bidirectional reflectance distribution function (BRDF) and the Fresnel law, and this model's outputs would be the incident light parameters of subsurface scattering. Using ocean subsurface scattering algorithm combined with bio-optical model, we compute the scattering light emergent radiation in different directions. Then, we blend the reflection of sunlight and sky light to implement the real-time ocean color rendering in graphics processing unit (GPU). Finally, we use two kinds of radiance reflectance calculated by Hydrolight radiative transfer model and our algorithm to validate the physical reality of our method, and the results show that our algorithm can achieve real-time highly realistic ocean color scenes.
A Real-Time Photo-Realistic Rendering Algorithm of Ocean Color Based on Bio-Optical Model
MA Chunyong; XU Shu; WANG Hongsong; TIAN Fenglin; CHEN Ge
2016-01-01
A real-time photo-realistic rendering algorithm of ocean color is introduced in the paper, which considers the impact of ocean bio-optical model. The ocean bio-optical model mainly involves the phytoplankton, colored dissolved organic material (CDOM), inorganic suspended particle,etc., which have different contributions to absorption and scattering of light. We decompose the emergent light of the ocean surface into the reflected light from the sun and the sky, and the subsurface scattering light. We estab-lish an ocean surface transmission model based on ocean bidirectional reflectance distribution function (BRDF) and the Fresnel law, and this model’s outputs would be the incident light parameters of subsurface scattering. Using ocean subsurface scattering algorithm combined with bio-optical model, we compute the scattering light emergent radiation in different directions. Then, we blend the re-flection of sunlight and sky light to implement the real-time ocean color rendering in graphics processing unit (GPU). Finally, we use two kinds of radiance reflectance calculated by Hydrolight radiative transfer model and our algorithm to validate the physical reality of our method, and the results show that our algorithm can achieve real-time highly realistic ocean color scenes.
A Practical Framework to Study Low-Power Scheduling Algorithms on Real-Time and Embedded Systems
Jian (Denny Lin
2014-05-01
Full Text Available With the advanced technology used to design VLSI (Very Large Scale Integration circuits, low-power and energy-efficiency have played important roles for hardware and software implementation. Real-time scheduling is one of the fields that has attracted extensive attention to design low-power, embedded/real-time systems. The dynamic voltage scaling (DVS and CPU shut-down are the two most popular techniques used to design the algorithms. In this paper, we firstly review the fundamental advances in the research of energy-efficient, real-time scheduling. Then, a unified framework with a real Intel PXA255 Xscale processor, namely real-energy, is designed, which can be used to measure the real performance of the algorithms. We conduct a case study to evaluate several classical algorithms by using the framework. The energy efficiency and the quantitative difference in their performance, as well as the practical issues found in the implementation of these algorithms are discussed. Our experiments show a gap between the theoretical and real results. Our framework not only gives researchers a tool to evaluate their system designs, but also helps them to bridge this gap in their future works.
Genovese, Mariangela; Napoli, Ettore
2013-05-01
The identification of moving objects is a fundamental step in computer vision processing chains. The development of low cost and lightweight smart cameras steadily increases the request of efficient and high performance circuits able to process high definition video in real time. The paper proposes two processor cores aimed to perform the real time background identification on High Definition (HD, 1920 1080 pixel) video streams. The implemented algorithm is the OpenCV version of the Gaussian Mixture Model (GMM), an high performance probabilistic algorithm for the segmentation of the background that is however computationally intensive and impossible to implement on general purpose CPU with the constraint of real time processing. In the proposed paper, the equations of the OpenCV GMM algorithm are optimized in such a way that a lightweight and low power implementation of the algorithm is obtained. The reported performances are also the result of the use of state of the art truncated binary multipliers and ROM compression techniques for the implementation of the non-linear functions. The first circuit has commercial FPGA devices as a target and provides speed and logic resource occupation that overcome previously proposed implementations. The second circuit is oriented to an ASIC (UMC-90nm) standard cell implementation. Both implementations are able to process more than 60 frames per second in 1080p format, a frame rate compatible with HD television.
Khitrov, Maxim Y; Rutishauser, Matthew; Montgomery, Kevin; Reisner, Andrew T; Reifman, Jaques
2009-01-01
The unavailability of a flexible system for realtime testing of decision-support algorithms in a pre-hospital clinical setting has limited their use. In this study, we describe a plug-and-play platform for real-time testing of decision-support algorithms during the transport of trauma casualties en route to a hospital. The platform integrates a standard-of-care vital-signs monitor, which collects numeric and waveform physiologic time-series data, with a rugged ultramobile personal computer. The computer time-stamps and stores data received from the monitor, and performs analysis on the collected data in real-time. Prior to field deployment, we assessed the performance of each component of the platform by using an emulator to simulate a number of possible fault scenarios that could be encountered in the field. Initial testing with the emulator allowed us to identify and fix software inconsistencies and showed that the platform can support a quick development cycle for real-time decision-support algorithms.
Sadeghi, Saman; MacKay, William A.; van Dam, R. Michael; Thompson, Michael
2011-02-01
Real-time analysis of multi-channel spatio-temporal sensor data presents a considerable technical challenge for a number of applications. For example, in brain-computer interfaces, signal patterns originating on a time-dependent basis from an array of electrodes on the scalp (i.e. electroencephalography) must be analyzed in real time to recognize mental states and translate these to commands which control operations in a machine. In this paper we describe a new technique for recognition of spatio-temporal patterns based on performing online discrimination of time-resolved events through the use of correlation of phase dynamics between various channels in a multi-channel system. The algorithm extracts unique sensor signature patterns associated with each event during a training period and ranks importance of sensor pairs in order to distinguish between time-resolved stimuli to which the system may be exposed during real-time operation. We apply the algorithm to electroencephalographic signals obtained from subjects tested in the neurophysiology laboratories at the University of Toronto. The extension of this algorithm for rapid detection of patterns in other sensing applications, including chemical identification via chemical or bio-chemical sensor arrays, is also discussed.
Siddhartha Sankar Biswas
2014-01-01
Full Text Available The networks of the present day communication systems, be it a public road transportation system or a MANET or an Adhoc Network, frequently face a lot of uncertainties in particular regarding traffic jam, flood or water logging or PWD maintenance work (in case of public road network, attack or damage from internal or external agents, sudden failure of one or few nodes. Consequently, at a real instant of time, the existing links/arcs of a given network (graph are not always in their original/excellent condition physically or logically, rather in a weaker condition, or even sometimes disabled or blocked temporarily and waiting for maintenance/repair; and hence ultimately causing delay in communication or transportation. We do not take any special consideration if few of the links be in a better condition at the real time of communication, we consider only such cases where few links are in inferior condition (partially or fully damaged. The classical Dijkstra’s algorithm to find the shortest path in graphs is applicable only if we assume that all the links of the concerned graph are available at their original (ideal condition at that real time of communication, but at real time scenario it is not the case. Consequently, the mathematically calculated shortest path extracted by using Dijkstra’s algorithm may become costlier (even in-feasible in some cases in terms of time and/or in terms of other overhead costs; whereas some other path may be the most efficient or most optimal. Many real life situations of communication network or transportation network cannot be modeled into graphs, but can be well modeled into multigraphs because of the scope of dealing with multiple links (or arcs connecting a pair of nodes. The classical Dijkstra’s algorithm to find the shortest path in graphs is not applicable to multigraphs. In this study the authors make a refinement of the classical Dijkstra’s algorithm to make it applicable to directed multigraphs
Haustein Thomas
2006-01-01
Full Text Available A recently realized concept of a reconfigurable hardware test-bed suitable for real-time mobile communication with multiple antennas is presented in this paper. We discuss the reasons and prerequisites for real-time capable MIMO transmission systems which may allow channel adaptive transmission to increase link stability and data throughput. We describe a concept of an efficient implementation of MIMO signal processing using FPGAs and DSPs. We focus on some basic linear and nonlinear MIMO detection and precoding algorithms and their optimization for a DSP target, and a few principal steps for computational performance enhancement are outlined. An experimental verification of several real-time MIMO transmission schemes at high data rates in a typical office scenario is presented and results on the achieved BER and throughput performance are given. The different transmission schemes used either channel state information at both sides of the link or at one side only (transmitter or receiver. Spectral efficiencies of more than 20 bits/s/Hz and a throughput of more than 150 Mbps were shown with a single-carrier transmission. The experimental results clearly show the feasibility of real-time high data rate MIMO techniques with state-of-the-art hardware and that more sophisticated baseband signal processing will be an essential part of future communication systems. A discussion on implementation challenges towards future wireless communication systems supporting higher data rates (1 Gbps and beyond or high mobility concludes the paper.
The XH-map algorithm: A method to process stereo video to produce a real-time obstacle map
Rosselot, Donald; Hall, Ernest L.
2005-10-01
This paper presents a novel, simple and fast algorithm to produce a "floor plan" obstacle map in real time using video. The XH-map algorithm is a transformation of stereo vision data in disparity map space into a two dimensional obstacle map space using a method that can be likened to a histogram reduction of image information. The classic floor-ground background noise problem is addressed with a simple one-time semi-automatic calibration method incorporated into the algorithm. This implementation of this algorithm utilizes the Intel Performance Primitives library and OpenCV libraries for extremely fast and efficient execution, creating a scaled obstacle map from a 480x640x256 stereo pair in 1.4 milliseconds. This algorithm has many applications in robotics and computer vision including enabling an "Intelligent Robot" robot to "see" for path planning and obstacle avoidance.
Hui Zhou
2016-10-01
Full Text Available Real-time detection of gait events can be applied as a reliable input to control drop foot correction devices and lower-limb prostheses. Among the different sensors used to acquire the signals associated with walking for gait event detection, the accelerometer is considered as a preferable sensor due to its convenience of use, small size, low cost, reliability, and low power consumption. Based on the acceleration signals, different algorithms have been proposed to detect toe off (TO and heel strike (HS gait events in previous studies. While these algorithms could achieve a relatively reasonable performance in gait event detection, they suffer from limitations such as poor real-time performance and are less reliable in the cases of up stair and down stair terrains. In this study, a new algorithm is proposed to detect the gait events on three walking terrains in real-time based on the analysis of acceleration jerk signals with a time-frequency method to obtain gait parameters, and then the determination of the peaks of jerk signals using peak heuristics. The performance of the newly proposed algorithm was evaluated with eight healthy subjects when they were walking on level ground, up stairs, and down stairs. Our experimental results showed that the mean F1 scores of the proposed algorithm were above 0.98 for HS event detection and 0.95 for TO event detection on the three terrains. This indicates that the current algorithm would be robust and accurate for gait event detection on different terrains. Findings from the current study suggest that the proposed method may be a preferable option in some applications such as drop foot correction devices and leg prostheses.
Intelligent, Real-Time Problem Solving. Phase 3
1992-04-30
approach, and to develop a heuristic algorithm for design-to-time real-time scheduling. E .velopes. During Phase III we extended our work on the real...the anytime algorithm approach, and presents a heuristic algorithm for design-to-time real-time scheduling. The methodology is known as design-to
Development of real-time diagnostics and feedback algorithms for JET in view of the next step
Murari, A [Consorzio RFX-Associazione EURATOM ENEA per la Fusione, Corso Stati Uniti 4, I-35127, Padua (Italy); Joffrin, E [Association EURATOM-CEA, CEA Cadarache, 13108 Saint-Paul-lez-Durance (France); Felton, R [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Mazon, D [Association EURATOM-CEA, CEA Cadarache, 13108 Saint-Paul-lez-Durance (France); Zabeo, L [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Albanese, R [Assoc. Euratom-ENEA-CREATE, Univ. Mediterranea RC, Loc. Feo di Vito, I-89060, RC (Italy); Arena, P [Assoc. Euratom-ENEA-CREATE, Univ. di Catania (Italy); Ambrosino, G [Assoc. Euratom-ENEA-CREATE, Univ. Napoli Federico II, Via Claudio 21, I-80125 Naples (Italy); Ariola, M [Assoc. Euratom-ENEA-CREATE, Univ. Napoli Federico II, Via Claudio 21, I-80125 Napoli (Italy); Barana, O [Consorzio RFX-Associazione EURATOM ENEA per la Fusione, Corso Stati Uniti 4, I-35127, Padua (Italy); Bruno, M [Assoc. Euratom-ENEA-CREATE, Univ. di Catania (Italy); Laborde, L [Association EURATOM-CEA, CEA Cadarache, 13108 Saint-Paul-lez-Durance (France); Moreau, D [Association EURATOM-CEA, CEA Cadarache, 13108 Saint-Paul-lez-Durance (France); Piccolo, F [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Sartori, F [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Crisanti, F [Associazone EURATOM ENEA sulla Fusione, C.R. Frascati (Italy); Luna, E de la [Associacion EURATOM CIEMAT para Fusion, Avenida Complutense 22, E-28040 Madrid (Spain); Sanchez, J [Associacion EURATOM CIEMAT para Fusion, Avenida Complutense 22, E-28040 Madrid (Spain)
2005-03-01
Real-time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of next step tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real-time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. Some of the signals now routinely provided in real time at JET are: (i) the internal inductance and the main confinement quantities obtained by calculating the Shafranov integrals from the pick-up coils with 2 ms time resolution; (ii) the electron temperature profile, from electron cyclotron emission every 10 ms; (iii) the ion temperature and plasma toroidal velocity profiles, from charge exchange recombination spectroscopy, provided every 50 ms; and (iv) the safety factor profile, derived from the inversion of the polarimetric line integrals every 2 ms. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. With these new tools, several real-time schemes were implemented, among which the most significant is the simultaneous control of the safety factor and the plasma pressure profiles using the additional heating systems (LH, NBI, ICRH) as actuators. The control strategy adopted in this case consists of a multi-variable model-based technique, which was implemented as a truncated singular value decomposition of an integral operator. This approach is considered essential for systems like tokamak machines, characterized by a strong mutual dependence of the various parameters and the distributed nature of the quantities, the plasma profiles, to be controlled. First encouraging results were also obtained using non-algorithmic
2006-01-01
TUF’s, and have mutual exclusion resource dependencies. This scheduling problem can be shown to be NP-hard. We present a heuristic algorithm for...be NP-hard in [2], and in [4], respectively. The GUS algorithm presented here is therefore a heuristic algorithm that seeks to maximize the total
Zhao, X.; Rosen, D. W.
2017-01-01
As additive manufacturing is poised for growth and innovations, it faces barriers of lack of in-process metrology and control to advance into wider industry applications. The exposure controlled projection lithography (ECPL) is a layerless mask-projection stereolithographic additive manufacturing process, in which parts are fabricated from photopolymers on a stationary transparent substrate. To improve the process accuracy with closed-loop control for ECPL, this paper develops an interferometric curing monitoring and measuring (ICM&M) method which addresses the sensor modeling and algorithms issues. A physical sensor model for ICM&M is derived based on interference optics utilizing the concept of instantaneous frequency. The associated calibration procedure is outlined for ICM&M measurement accuracy. To solve the sensor model, particularly in real time, an online evolutionary parameter estimation algorithm is developed adopting moving horizon exponentially weighted Fourier curve fitting and numerical integration. As a preliminary validation, simulated real-time measurement by offline analysis of a video of interferograms acquired in the ECPL process is presented. The agreement between the cured height estimated by ICM&M and that measured by microscope indicates that the measurement principle is promising as real-time metrology for global measurement and control of the ECPL process.
Filho, Faete J [ORNL; Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL
2012-01-01
The work developed here proposes a methodology for calculating switching angles for varying DC sources in a multilevel cascaded H-bridges converter. In this approach the required fundamental is achieved, the lower harmonics are minimized, and the system can be implemented in real time with low memory requirements. Genetic algorithm (GA) is the stochastic search method to find the solution for the set of equations where the input voltages are the known variables and the switching angles are the unknown variables. With the dataset generated by GA, an artificial neural network (ANN) is trained to store the solutions without excessive memory storage requirements. This trained ANN then senses the voltage of each cell and produces the switching angles in order to regulate the fundamental at 120 V and eliminate or minimize the low order harmonics while operating in real time.
Real-Time Image Matching Using the Trajkovic and Hedley Algorithm
Mary Jane Samonte
2013-06-01
Full Text Available One way to acquire information is through surveillance videos. Changes in the video feed can be seen more accurately through image matching. There are several approaches to image matching; and one of these is the SIFT algorithm. Aside from SIFT, Trajkovic and Hedley is another, if not the fastest and most efficient, of the corner detection algorithms. By replacing the keypoint extraction of the SIFT algorithm to the Trajkovic and Hedley corner detection algorithm, the SIFT algorithm will become faster. The study is composed of different phases, including Pre-Processing, Feature Extraction and the Matching Phase. This study has two objectives: to introduce a new method when it comes to image matching, especially with the use of the SIFT algorithm, and the use of other approaches as alternatives used in surveillance and security.
An MCMC Algorithm for Target Estimation in Real-Time DNA Microarrays
Vikalo Haris
2010-01-01
Full Text Available DNA microarrays detect the presence and quantify the amounts of nucleic acid molecules of interest. They rely on a chemical attraction between the target molecules and their Watson-Crick complements, which serve as biological sensing elements (probes. The attraction between these biomolecules leads to binding, in which probes capture target analytes. Recently developed real-time DNA microarrays are capable of observing kinetics of the binding process. They collect noisy measurements of the amount of captured molecules at discrete points in time. Molecular binding is a random process which, in this paper, is modeled by a stochastic differential equation. The target analyte quantification is posed as a parameter estimation problem, and solved using a Markov Chain Monte Carlo technique. In simulation studies where we test the robustness with respect to the measurement noise, the proposed technique significantly outperforms previously proposed methods. Moreover, the proposed approach is tested and verified on experimental data.
Improvement of a picking algorithm real-time P-wave detection by kurtosis
Ishida, H.; Yamada, M.
2016-12-01
Earthquake early warning (EEW) requires fast and accurate P-wave detection. The current EEW system in Japan uses the STA/LTAalgorithm (Allen, 1978) to detect P-wave arrival.However, some stations did not trigger during the 2011 Great Tohoku Earthquake due to the emergent onset. In addition, accuracy of the P-wave detection is very important: on August 1, 2016, the EEW issued a false alarm with M9 in Tokyo region due to a thunder noise.To solve these problems, we use a P-wave detection method using kurtosis statistics. It detects the change of statistic distribution of the waveform amplitude. This method was recently developed (Saragiotis et al., 2002) and used for off-line analysis such as making seismic catalogs. To apply this method for EEW, we need to remove an acausal calculation and enable a real-time processing. Here, we propose a real-time P-wave detection method using kurtosis statistics with a noise filter.To avoid false triggering by a noise, we incorporated a simple filter to classify seismic signal and noise. Following Kong et al. (2016), we used the interquartilerange and zero cross rate for the classification. The interquartile range is an amplitude measure that is equal to the middle 50% of amplitude in a certain time window. The zero cross rate is a simple frequency measure that counts the number of times that the signal crosses baseline zero. A discriminant function including these measures was constructed by the linear discriminant analysis.To test this kurtosis method, we used strong motion records for 62 earthquakes between April, 2005 and July, 2015, which recorded the seismic intensity greater equal to 6 lower in the JMA intensity scale. The records with hypocentral distance earthquakes and improve the shaking intensity estimation for an earthquake early warning.
Johnson, R.; Hernandez, J.E.; Lu, Shin-yee [Lawrence Livermore National Lab., CA (United States)
1994-11-15
Many industrial and defence applications require an ability to make instantaneous decisions based on sensor input of a time varying process. Such systems are referred to as `real-time systems` because they process and act on data as it occurs in time. When a vision sensor is used in a real-time system, the processing demands can be quite substantial, with typical data rates of 10-20 million samples per second. A real-time Machine Vision Laboratory (MVL) was established in FY94 to extend our years of experience in developing computer vision algorithms to include the development and implementation of real-time vision systems. The laboratory is equipped with a variety of hardware components, including Datacube image acquisition and processing boards, a Sun workstation, and several different types of CCD cameras, including monochrome and color area cameras and analog and digital line-scan cameras. The equipment is reconfigurable for prototyping different applications. This facility has been used to support several programs at LLNL, including O Division`s Peacemaker and Deadeye Projects as well as the CRADA with the U.S. Textile Industry, CAFE (Computer Aided Fabric Inspection). To date, we have successfully demonstrated several real-time applications: bullet tracking, stereo tracking and ranging, and web inspection. This work has been documented in the ongoing development of a real-time software library.
An Optimal Flow Control Algorithm for Real-time Traffic over the Internet
无
2001-01-01
According to the Wide Area Network model and queue dynamics in the router, the authors formulate the Internet flow control as a constrained convex programming problem, where the objective is to maximize the total utility and minimize transmission delay and delay jitter of all sources over their transmission rates. Based on this formulation, flow control can be solved by means of a gradient projection algorithm with properly rate iterations. The main difficulty facing the realization of the iteration algorithm is the distributed computation of the congestion measure. Fortunately, Explicit Congestion Notification (ECN) is likely to be used to improving the performance of TCP in the near future. By using ECN, it is possible to realize the iteration algorithm in IP networks. The algorithm is divided into two parts, algorithms in the router and the source. The main advantage of the scheme is its fast convergence ability and robustness, but small queue length fluctuation is unavoidable when the number of users increases.
Hoang, TY
1994-01-01
A real-time, high-rate precision navigation Kalman filter algorithm is developed and analyzed. This Navigation algorithm blends various navigation data collected during terminal area approach of an instrumented helicopter. Navigation data collected include helicopter position and velocity from a global position system in differential mode (DGPS) as well as helicopter velocity and attitude from an inertial navigation system (INS). The goal of the Navigation algorithm is to increase the DGPS accuracy while producing navigational data at the 64 Hertz INS update rate. It is important to note that while the data was post flight processed, the Navigation algorithm was designed for real-time analysis. The design of the Navigation algorithm resulted in a nine-state Kalman filter. The Kalman filter's state matrix contains position, velocity, and velocity bias components. The filter updates positional readings with DGPS position, INS velocity, and velocity bias information. In addition, the filter incorporates a sporadic data rejection scheme. This relatively simple model met and exceeded the ten meter absolute positional requirement. The Navigation algorithm results were compared with truth data derived from a laser tracker. The helicopter flight profile included terminal glideslope angles of 3, 6, and 9 degrees. Two flight segments extracted during each terminal approach were used to evaluate the Navigation algorithm. The first segment recorded small dynamic maneuver in the lateral plane while motion in the vertical plane was recorded by the second segment. The longitudinal, lateral, and vertical averaged positional accuracies for all three glideslope approaches are as follows (mean plus or minus two standard deviations in meters): longitudinal (-0.03 plus or minus 1.41), lateral (-1.29 plus or minus 2.36), and vertical (-0.76 plus or minus 2.05).
Proposed Fuzzy CPU Scheduling Algorithm (PFCS for Real Time Operating Systems
Prerna Ajmani
2013-12-01
Full Text Available In the era of supercomputers multiprogramming operating system has emerged. Multiprogramming operating system allows more than one ready to execute processes to be loaded into memory. CPU scheduling is the process of selecting from among the processes in memory that are ready to execute and allocate the processor time (CPU to it. Many conventional algorithms have been proposed for scheduling CPU such as FCFS, shortest job first (SJF, priority scheduling etc. But no algorithm is absolutely ideal in terms of increased throughput, decreased waiting time, decreased turnaround time etc. In this paper, a new fuzzy logic based CPU scheduling algorithm has been proposed to overcome the drawbacks of conventional algorithms for efficient utilization of CPU.
A survey of the baseline correction algorithms for real-time spectroscopy processing
Liu, Yuanjie; Yu, Yude
2016-11-01
In spectroscopy data analysis, such as Raman spectra, X-ray diffraction, fluorescence and etc., baseline drift is a ubiquitous issue. In high speed testing which generating huge data, automatic baseline correction method is very important for efficient data processing. We will survey the algorithms from classical Shirley background to state-of-the-art methods to present a summation for this specific field. Both advantages and defects of each algorithm are scrutinized. To compare the algorithms with each other, experiments are also carried out under SVM gap gain criteria to show the performance quantitatively. Finally, a rank table of these methods is built and the suggestions for practical choice of adequate algorithms is provided in this paper.
Real-Time Implementation of an Efficient Speech Enhancement Algorithm for Digital Hearing Aids
GAO Jie; ZHANG Hui; HU Guangshu
2006-01-01
In order to remove background noise and improve the quality of speech for digital hearing aids, a single-channel speech enhancement algorithm is proposed. The algorithm is implemented and assessed on a digital hearing aid platform based on the TI DSP TMS320VC5502 chip. Assuming that background noise is stationary or varies slowly, an energy-based voice activity detection algorithm is adopted by adaptively tracking the minima and maxima of the power envelope in noisy speech. The target speech is then enhanced by using a Wiener filter, on the basis of a short-term power spectral estimation. To deal with the distracting musical noise of the processed speech, phase randomization, along with adjacent spectral averaging, is adopted. Objective measures and an informal hearing test both show an improved performance as well as obvious attenuation of residual noise. The low power consumption and high efficiency render the whole algorithm very applicable for use in digital hearing aids.
A New Anti-Collision Algorithm for Multi-Target Real Time Recognition in RFID System
无
2000-01-01
The problem of how to distinguish and recognize more than one target when they are entering the working area of the Radio Frequency Jdenti fication (RFID) system should be considered in design of the system. To avoid signal interference with each other among all targets, an anti-collision algorithm as well as the condition of working stability is proposed. The computer simulation shows that the new algorithm will be of advantages in the process of system design.
Mateos-Pérez, José María; Redondo, Rafael; Nava, Rodrigo; Valdiviezo, Juan C; Cristóbal, Gabriel; Escalante-Ramírez, Boris; Ruiz-Serrano, María Jesús; Pascau, Javier; Desco, Manuel
2012-03-01
Microscopy images must be acquired at the optimal focal plane for the objects of interest in a scene. Although manual focusing is a standard task for a trained observer, automatic systems often fail to properly find the focal plane under different microscope imaging modalities such as bright field microscopy or phase contrast microscopy. This article assesses several autofocus algorithms applied in the study of fluorescence-labeled tuberculosis bacteria. The goal of this work was to find the optimal algorithm in order to build an automatic real-time system for diagnosing sputum smear samples, where both accuracy and computational time are important. We analyzed 13 focusing methods, ranging from well-known algorithms to the most recently proposed functions. We took into consideration criteria that are inherent to the autofocus function, such as accuracy, computational cost, and robustness to noise and to illumination changes. We also analyzed the additional benefit provided by preprocessing techniques based on morphological operators and image projection profiling.
Cao, Minh Duc; Ganesamoorthy, Devika; Elliott, Alysha G; Zhang, Huihui; Cooper, Matthew A; Coin, Lachlan J M
2016-07-26
The recently introduced Oxford Nanopore MinION platform generates DNA sequence data in real-time. This has great potential to shorten the sample-to-results time and is likely to have benefits such as rapid diagnosis of bacterial infection and identification of drug resistance. However, there are few tools available for streaming analysis of real-time sequencing data. Here, we present a framework for streaming analysis of MinION real-time sequence data, together with probabilistic streaming algorithms for species typing, strain typing and antibiotic resistance profile identification. Using four culture isolate samples, as well as a mixed-species sample, we demonstrate that bacterial species and strain information can be obtained within 30 min of sequencing and using about 500 reads, initial drug-resistance profiles within two hours, and complete resistance profiles within 10 h. While strain identification with multi-locus sequence typing required more than 15x coverage to generate confident assignments, our novel gene-presence typing could detect the presence of a known strain with 0.5x coverage. We also show that our pipeline can process over 100 times more data than the current throughput of the MinION on a desktop computer.
Real Time Efficient Scheduling Algorithm for Load Balancing in Fog Computing Environment
Manisha Verma
2016-04-01
Full Text Available Cloud computing is the new era technology, which is entirely dependent on the internet to maintain large applications, where data is shared over one platform to provide better services to clients belonging to a different organization. It ensures maximum utilization of computational resources by making availability of data, software and infrastructure with lower cost in a secure, reliable and flexible manner. Though cloud computing offers many advantages, but it suffers from certain limitation too, that during load balancing of data in cloud data centers the internet faces problems of network congestion, less bandwidth utilization, fault tolerance and security etc. To get rid out of this issue new computing model called Fog Computing is introduced which easily transfer sensitive data without delaying to distributed devices. Fog is similar to the cloud only difference lies in the fact that it is located more close to end users to process and give response to the client in less time. Secondly, it is beneficial to the real time streaming applications, sensor networks, Internet of things which need high speed and reliable internet connectivity. Our proposed architecture introduced a new scheduling policy for load balancing in Fog Computing environment, which complete real tasks within deadline, increase throughput and network utilization, maintaining data consistency with less complexity to meet the present day demand of end users
Parallel waveform extraction algorithms for the Cherenkov Telescope Array Real-Time Analysis
Zoli, Andrea; De Rosa, Adriano; Aboudan, Alessio; Fioretti, Valentina; De Cesare, Giovanni; Marx, Ramin
2015-01-01
The Cherenkov Telescope Array (CTA) is the next generation observatory for the study of very high-energy gamma rays from about 20 GeV up to 300 TeV. Thanks to the large effective area and field of view, the CTA observatory will be characterized by an unprecedented sensitivity to transient flaring gamma-ray phenomena compared to both current ground (e.g. MAGIC, VERITAS, H.E.S.S.) and space (e.g. Fermi) gamma-ray telescopes. In order to trigger the astrophysics community for follow-up observations, or being able to quickly respond to external science alerts, a fast analysis pipeline is crucial. This will be accomplished by means of a Real-Time Analysis (RTA) pipeline, a fast and automated science alert trigger system, becoming a key system of the CTA observatory. Among the CTA design key requirements to the RTA system, the most challenging is the generation of alerts within 30 seconds from the last acquired event, while obtaining a flux sensitivity not worse than the one of the final analysis by more than a fac...
A Real-Time Algorithm for Intelligent Control Embedded in Knowledge based Systems
Vasile MAZILESCU
2011-11-01
Full Text Available Consistent with the growing interest in organizational knowledge and Knowledge Management, many ICT researchers have been promoting a class of Knowledge Management Systems (KMSs, referred as Knowledge based Systems. The objective of a KMS is to support knowledge capturing, categorizing, storing, searching, distributing and application within organizations. Technical advances in computers’ processing and storage capacity, together with linking these computers into networks of distributed nodes, have greatly increased the organizations’ capability to deliver goods and services. Along with these capabilities we need quality, accuracy, responsiveness and capacity. The aim of this paper is to present a Knowledge Management System based on Fuzzy Logic (KMSFL, a real-time expert system to meet the challenges of the dynamic environment. The main feature of our integrated shell KMSFL is that it models and integrates the temporal relationships between the dynamic of the process evolution with some fuzzy inferential methods, using a knowledge model for control, embedded within the expert system’s operational knowledge base.
Sarigiannis, Dimosthenis A; Karakitsios, Spyros P; Gotti, Alberto; Papaloukas, Costas L; Kassomenos, Pavlos A; Pilidis, Georgios A
2009-01-01
The objective of the current study was the development of a reliable modeling platform to calculate in real time the personal exposure and the associated health risk for filling station employees evaluating current environmental parameters (traffic, meteorological and amount of fuel traded) determined by the appropriate sensor network. A set of Artificial Neural Networks (ANNs) was developed to predict benzene exposure pattern for the filling station employees. Furthermore, a Physiology Based Pharmaco-Kinetic (PBPK) risk assessment model was developed in order to calculate the lifetime probability distribution of leukemia to the employees, fed by data obtained by the ANN model. Bayesian algorithm was involved in crucial points of both model sub compartments. The application was evaluated in two filling stations (one urban and one rural). Among several algorithms available for the development of the ANN exposure model, Bayesian regularization provided the best results and seemed to be a promising technique for prediction of the exposure pattern of that occupational population group. On assessing the estimated leukemia risk under the scope of providing a distribution curve based on the exposure levels and the different susceptibility of the population, the Bayesian algorithm was a prerequisite of the Monte Carlo approach, which is integrated in the PBPK-based risk model. In conclusion, the modeling system described herein is capable of exploiting the information collected by the environmental sensors in order to estimate in real time the personal exposure and the resulting health risk for employees of gasoline filling stations.
Pavlos A. Kassomenos
2009-02-01
Full Text Available The objective of the current study was the development of a reliable modeling platform to calculate in real time the personal exposure and the associated health risk for filling station employees evaluating current environmental parameters (traffic, meteorological and amount of fuel traded determined by the appropriate sensor network. A set of Artificial Neural Networks (ANNs was developed to predict benzene exposure pattern for the filling station employees. Furthermore, a Physiology Based Pharmaco-Kinetic (PBPK risk assessment model was developed in order to calculate the lifetime probability distribution of leukemia to the employees, fed by data obtained by the ANN model. Bayesian algorithm was involved in crucial points of both model sub compartments. The application was evaluated in two filling stations (one urban and one rural. Among several algorithms available for the development of the ANN exposure model, Bayesian regularization provided the best results and seemed to be a promising technique for prediction of the exposure pattern of that occupational population group. On assessing the estimated leukemia risk under the scope of providing a distribution curve based on the exposure levels and the different susceptibility of the population, the Bayesian algorithm was a prerequisite of the Monte Carlo approach, which is integrated in the PBPK-based risk model. In conclusion, the modeling system described herein is capable of exploiting the information collected by the environmental sensors in order to estimate in real time the personal exposure and the resulting health risk for employees of gasoline filling stations.
Research on Linux Real-time Scheduling Algorithm%Linux实时调度算法研究
吴振亚; 李航; 苏锐丹
2015-01-01
With the popularity of Linux,the real-time features of Linux have attracted more attention,but there is a little research survey in this field at present,and existed survey mainly classifies real-time scheduling algorithm according to structure of algorithm rather,than from the user' s view,classifying according to the problem pattern. So,it' s not easy to guide the practice in industry by this way. For this reason,classify the real-time scheduling algorithm according to the problem pattern. The principles that the classification follows are from inside to outside,from general problem scenario to specific problem scenario. Finally,a well-organized hierarchy is obtained. The benefits of this classification are that besides guiding the practice of industry more easily,it describes the nature of real-time scheduling algorithm more accurately.%随着Linux的普及,Linux的实时性越来越受重视,但目前对该领域内研究进行综述的工作较少,并且已有的综述性工作主要从算法的自身结构对实时调度算法进行划分,而非从使用者的角度,根据解决的问题模式去划分,从而不易于指导工业级的应用实践。为此,文中从Linux实时调度算法所针对的问题模式出发,对实时算法进行分类。分类基于由内到外,从通用问题场景到具体应用问题场景的原则,最终形成了层次良好的分类结构。该分类的优点在于：除了更易于指导工业级的应用实践,也更加准确地描述了实时调度算法的本质特征。
A modular low-complexity ECG delineation algorithm for real-time embedded systems.
Bote, Jose Manuel; Recas, Joaquin; Rincon, Francisco; Atienza, David; Hermida, Roman
2017-02-17
This work presents a new modular and lowcomplexity algorithm for the delineation of the different ECG waves (QRS, P and T peaks, onsets and end). Involving a reduced number of operations per second and having a small memory footprint, this algorithm is intended to perform realtime delineation on resource-constrained embedded systems. The modular design allows the algorithm to automatically adjust the delineation quality in run time to a wide range of modes and sampling rates, from a Ultra-low power mode when no arrhythmia is detected, in which the ECG is sampled at low frequency, to a complete High-accuracy delineation mode in which the ECG is sampled at high frequency and all the ECG fiducial points are detected, in case of arrhythmia. The delineation algorithm has been adjusted using the QT database, providing very high sensitivity and positive predictivity, and validated with the MIT database. The errors in the delineation of all the fiducial points are below the tolerances given by the Common Standards for Electrocardiography (CSE) committee in the High-accuracy mode, except for the P wave onset, for which the algorithm is above the agreed tolerances by only a fraction of the sample duration. The computational load for the ultra-low-power 8-MHz TI MSP430 series microcontroller ranges from 0.2 to 8.5% according to the mode used.
Alcock, C B; Allsman, R A; Alves, D R; Axelrod, T S; Banks, T; Beaulieu, S F; Becker, A C; Becker, R H; Bennett, D P; Bond, I A; Carter, B S; Cook, K H; Dodd, R J; Freeman, K C; Gregg, M D; Griest, K; Hearnshaw, J B; Heller, A; Honda, M; Juga Ku Jun; Kabe, S; Kaspi, S; Kilmartin, P M; Kitamura, A; Kovo, O; Lehner, M J; Love, T E; Maoz, D; Marshall, S L; Matsubara, Y; Minniti, D; Miyamoto, M; Muraki, Y; Nakamura, T; Peterson, B A; Pratt, M R; Quinn, P J; Reid, I N; Reid, M; Reiss, D; Retter, A; Rodgers, A W; Sargent, W L W; Sato, H; Sekiguchi, M; Stetson, P B; Stubbs, C W; Sullivan, D J; Sutherland, W; Tomaney, A B; Vandehei, T; Watase, Y; Welch, D L; Yanagisawa, T; Yoshizawa, M; Yock, P C M
1997-01-01
We present analysis of MACHO Alert 95-30, a dramatic gravitational microlensing event towards the Galactic bulge whose peak magnification departs significantly from the standard point-source microlensing model. Alert 95-30 was observed in real-time by the Global Microlensing Alert Network (GMAN), which obtained densely sampled photometric and spectroscopic data throughout the event. We interpret the light-curve ``fine structure'' as indicating transit of the lens across the extended face of the source star. This signifies resolution of a star several kpc distant. We find a lens angular impact parameter theta_{min}/theta_{source} = 0.715 +/- 0.003. This information, along with the radius and distance of the source, provides an additional constraint on the lensing system. Spectroscopic and photometric data indicate the source is an M4 III star of radius 61 +/- 12 Rsun, located on the far side of the bulge at 9 kpc. We derive a lens angular velocity, relative to the source, of 21.5 +/- 4.9 km/s/kpc, where the er...
Zhi-An Deng
2015-04-01
Full Text Available Indoor localization systems using WiFi received signal strength (RSS or pedestrian dead reckoning (PDR both have their limitations, such as the RSS fluctuation and the accumulative error of PDR. To exploit their complementary strengths, most existing approaches fuse both systems by a particle filter. However, the particle filter is unsuitable for real time localization on resource-limited smartphones, since it is rather time-consuming and computationally expensive. On the other hand, the light computation fusion approaches including Kalman filter and its variants are inapplicable, since an explicit RSS-location measurement equation and the related noise statistics are unavailable. This paper proposes a novel data fusion framework by using an extended Kalman filter (EKF to integrate WiFi localization with PDR. To make EKF applicable, we develop a measurement model based on kernel density estimation, which enables accurate WiFi localization and adaptive measurement noise statistics estimation. For the PDR system, we design another EKF based on quaternions for heading estimation by fusing gyroscopes and accelerometers. Experimental results show that the proposed EKF based data fusion approach achieves significant localization accuracy improvement over using WiFi localization or PDR systems alone. Compared with a particle filter, the proposed approach achieves comparable localization accuracy, while it incurs much less computational complexity.
A Self-Adaptive Parameter Optimization Algorithm in a Real-Time Parallel Image Processing System
Ge Li
2013-01-01
Full Text Available Aiming at the stalemate that precision, speed, robustness, and other parameters constrain each other in the parallel processed vision servo system, this paper proposed an adaptive load capacity balance strategy on the servo parameters optimization algorithm (ALBPO to improve the computing precision and to achieve high detection ratio while not reducing the servo circle. We use load capacity functions (LC to estimate the load for each processor and then make continuous self-adaptation towards a balanced status based on the fluctuated LC results; meanwhile, we pick up a proper set of target detection and location parameters according to the results of LC. Compared with current load balance algorithm, the algorithm proposed in this paper is proceeded under an unknown informed status about the maximum load and the current load of the processors, which means it has great extensibility. Simulation results showed that the ALBPO algorithm has great merits on load balance performance, realizing the optimization of QoS for each processor, fulfilling the balance requirements of servo circle, precision, and robustness of the parallel processed vision servo system.
An improved real-time endovascular guidewire position simulation using shortest path algorithm.
Qiu, Jianpeng; Qu, Zhiyi; Qiu, Haiquan; Zhang, Xiaomin
2016-09-01
In this study, we propose a new graph-theoretical method to simulate guidewire paths inside the carotid artery. The minimum energy guidewire path can be obtained by applying the shortest path algorithm, such as Dijkstra's algorithm for graphs, based on the principle of the minimal total energy. Compared to previous results, experiments of three phantoms were validated, revealing that the first and second phantoms overlap completely between simulated and real guidewires. In addition, 95 % of the third phantom overlaps completely, and the remaining 5 % closely coincides. The results demonstrate that our method achieves 87 and 80 % improvements for the first and third phantoms under the same conditions, respectively. Furthermore, 91 % improvements were obtained for the second phantom under the condition with reduced graph construction complexity.
A Night Time Application for a Real-Time Vehicle Detection Algorithm Based on Computer Vision
Shifu Zhou
2013-03-01
Full Text Available Vehicle detection technology is the key technology of intelligent transportation systems, attracting the attention of many researchers. Although much literature has been published concerning daytime vehicle detection, little has been published concerning nighttime vehicle detection. In this study, a nighttime vehicle detection algorithm, consisting of headlight segmentation, headlight pairing and headlight tracking, is proposed. First, the pixels of the headlights are segmented in nighttime traffic images, through the use of the thresholding method. Then the pixels of the headlights are grouped and labeled, to analyze the characteristics of related components, such as area, location and size. Headlights are paired based on their location and size and then tracked via a tracking procedure designed to detect vehicles. Vehicles with only one headlight or those with three or four headlights are also detected. Experimental results show that the proposed algorithm is robust and effective in detecting vehicles in nighttime traffic.
Real-time rescheduling metaheuristic algorithms applied to FMS with routing flexibility
2013-01-01
This paper presents the results of a simulation study of a typical flexible manufacturing system that consists of seven machining centres, a loading and an unloading area, and six different part types. Owing to the existence of identical machining centres, the part types have alternative routings (their number varies between two and eight). One of the objectives of this work is to show how the following metaheuristics: ant colony optimisation, genetic algorithms, simulated annealing, tabu sea...
Xin Li
2016-06-01
Full Text Available The problem of heading drift error using only low cost Micro-Electro-Mechanical (MEMS Inertial-Measurement-Unit (IMU has not been well solved. In this paper, a heading estimation method with real-time compensation based on Kalman filter has been proposed, abbreviated as KHD. For the KHD method, a unified heading error model is established for various predictable errors in magnetic compass for pedestrian navigation, and an effective method for solving the model parameters is proposed in the indoor environment with regular structure. In addition, error model parameters are solved by Kalman filtering algorithm with building geometry information in order to achieve real-time heading compensation. The experimental results show that the KHD method can not only effectively correct the original heading information, but also effectively inhibit the accumulation effect of positioning errors. The performance observed in a field experiment performed on the fourth floor of the School of Environmental Science and Spatial Informatics (SESSI building on the China University of Mining and Technology (CUMT campus confirms that apply KHD method to PDR(Pedestrian Dead Reckoning algorithm can reliably achieve meter-level positioning using a low cost MEMS IMU only.
Synchronized Scheme of Continuous Space-Vector PWM with the Real-Time Control Algorithms
Oleschuk, V.; Blaabjerg, Frede
2004-01-01
This paper describes in details the basic peculiarities of a new method of feedforward synchronous pulsewidth modulation (PWM) of three-phase voltage source inverters for adjustable speed ac drives. It is applied to a continuous scheme of voltage space vector modulation. The method is based...... on a representation of the pulse patterns as a function of the fundamental and switching frequencies of the drive system. Accurate trigonometric algorithms of vector PWM have been analysed, and also compared with the algebraic ones based on linear approximation of the durations of active switching states from...
Kalaivani
2013-09-01
Full Text Available This paper presents concurrent vibration control of a laboratory scaled vibration isolator platform with Active Force Control (AFC using Iterative Learning Algorithm (ILA. The work investigates the performance of the traditional Proportional Integral Derivative Controller (PIDC with and without AFC using ILA for vibration suppression. The physical single degree of freedom quarter car has been interfaced with a personal computer using a National Instruments data acquisition card NI USB 6008. The controllers are designed and simulated using LabVIEW simulation software. The results infer that the PIDC with AFC using ILA works superior than the PIDC.
Statistical analysis of piloted simulation of real time trajectory optimization algorithms
Price, D. B.
1982-01-01
A simulation of time-optimal intercept algorithms for on-board computation of control commands is described. The effects of three different display modes and two different computation modes on the pilots' ability to intercept a moving target in minimum time were tested. Both computation modes employed singular perturbation theory to help simplify the two-point boundary value problem associated with trajectory optimization. Target intercept time was affected by both the display and computation modes chosen, but the display mode chosen was the only significant influence on the miss distance.
Hild, Jutta; Krüger, Wolfgang; Brüstle, Stefan; Trantelle, Patrick; Unmüßig, Gabriel; Voit, Michael; Heinze, Norbert; Peinsipp-Byma, Elisabeth; Beyerer, Jürgen
2017-05-01
Real-time motion video analysis is a challenging and exhausting task for the human observer, particularly in safety and security critical domains. Hence, customized video analysis systems providing functions for the analysis of subtasks like motion detection or target tracking are welcome. While such automated algorithms relieve the human operators from performing basic subtasks, they impose additional interaction duties on them. Prior work shows that, e.g., for interaction with target tracking algorithms, a gaze-enhanced user interface is beneficial. In this contribution, we present an investigation on interaction with an independent motion detection (IDM) algorithm. Besides identifying an appropriate interaction technique for the user interface - again, we compare gaze-based and traditional mouse-based interaction - we focus on the benefit an IDM algorithm might provide for an UAS video analyst. In a pilot study, we exposed ten subjects to the task of moving target detection in UAS video data twice, once performing with automatic support, once performing without it. We compare the two conditions considering performance in terms of effectiveness (correct target selections). Additionally, we report perceived workload (measured using the NASA-TLX questionnaire) and user satisfaction (measured using the ISO 9241-411 questionnaire). The results show that a combination of gaze input and automated IDM algorithm provides valuable support for the human observer, increasing the number of correct target selections up to 62% and reducing workload at the same time.
Real-time MRI-guided hyperthermia treatment using a fast adaptive algorithm.
Stakhursky, Vadim L; Arabe, Omar; Cheng, Kung-Shan; Macfall, James; Maccarini, Paolo; Craciunescu, Oana; Dewhirst, Mark; Stauffer, Paul; Das, Shiva K
2009-04-01
Magnetic resonance (MR) imaging is promising for monitoring and guiding hyperthermia treatments. The goal of this work is to investigate the stability of an algorithm for online MR thermal image guided steering and focusing of heat into the target volume. The control platform comprised a four-antenna mini-annular phased array (MAPA) applicator operating at 140 MHz (used for extremity sarcoma heating) and a GE Signa Excite 1.5 T MR system, both of which were driven by a control workstation. MR proton resonance frequency shift images acquired during heating were used to iteratively update a model of the heated object, starting with an initial finite element computed model estimate. At each iterative step, the current model was used to compute a focusing vector, which was then used to drive the next iteration, until convergence. Perturbation of the driving vector was used to prevent the process from stalling away from the desired focus. Experimental validation of the performance of the automatic treatment platform was conducted with two cylindrical phantom studies, one homogeneous and one muscle equivalent with tumor tissue (conductivity 50% higher) inserted, with initial focal spots being intentionally rotated 90 degrees and 50 degrees away from the desired focus, mimicking initial setup errors in applicator rotation. The integrated MR-HT treatment platform steered the focus of heating into the desired target volume in two quite different phantom tissue loads which model expected patient treatment configurations. For the homogeneous phantom test where the target was intentionally offset by 90 degrees rotation of the applicator, convergence to the proper phase focus in the target occurred after 16 iterations of the algorithm. For the more realistic test with a muscle equivalent phantom with tumor inserted with 50 degrees applicator displacement, only two iterations were necessary to steer the focus into the tumor target. Convergence improved the heating efficacy (the
Real-time MRI-guided hyperthermia treatment using a fast adaptive algorithm
Stakhursky, Vadim L.; Arabe, Omar; Cheng, Kung-Shan; MacFall, James; Maccarini, Paolo; Craciunescu, Oana; Dewhirst, Mark; Stauffer, Paul; Das, Shiva K.
2009-04-01
Magnetic resonance (MR) imaging is promising for monitoring and guiding hyperthermia treatments. The goal of this work is to investigate the stability of an algorithm for online MR thermal image guided steering and focusing of heat into the target volume. The control platform comprised a four-antenna mini-annular phased array (MAPA) applicator operating at 140 MHz (used for extremity sarcoma heating) and a GE Signa Excite 1.5 T MR system, both of which were driven by a control workstation. MR proton resonance frequency shift images acquired during heating were used to iteratively update a model of the heated object, starting with an initial finite element computed model estimate. At each iterative step, the current model was used to compute a focusing vector, which was then used to drive the next iteration, until convergence. Perturbation of the driving vector was used to prevent the process from stalling away from the desired focus. Experimental validation of the performance of the automatic treatment platform was conducted with two cylindrical phantom studies, one homogeneous and one muscle equivalent with tumor tissue (conductivity 50% higher) inserted, with initial focal spots being intentionally rotated 90° and 50° away from the desired focus, mimicking initial setup errors in applicator rotation. The integrated MR-HT treatment platform steered the focus of heating into the desired target volume in two quite different phantom tissue loads which model expected patient treatment configurations. For the homogeneous phantom test where the target was intentionally offset by 90° rotation of the applicator, convergence to the proper phase focus in the target occurred after 16 iterations of the algorithm. For the more realistic test with a muscle equivalent phantom with tumor inserted with 50° applicator displacement, only two iterations were necessary to steer the focus into the tumor target. Convergence improved the heating efficacy (the ratio of integral
Antonio M.Mora; Antonio Fernández-Ares; Juan J.Merelo; Pablo García-Sánchez; Carlos M.Fernandes
2012-01-01
This paper investigates the performance and the results of an evolutionary algorithm (EA) specifically designed for evolving the decision engine of a program (which,in this context,is called bot) that plays Planet Wars.This game,which was chosen for the Google Artificial Intelligence Challenge in 2010,requires the bot to deal with multiple target planets,while achieving a certain degree of adaptability in order to defeat different opponents in different scenarios.The decision engine of the bot is initially based on a set of rules that have been defined after an empirical study,and a genetic algorithm (GA) is used for tuning the set of constants,weights and probabilities that those rules include,and therefore,the general behaviour of the bot.Then,the bot is supplied with the evolved decision engine and the results obtained when competing with other bots (a bot offered by Google as a sparring partner,and a scripted bot with a pre-established behaviour) are thoroughly analysed.The evaluation of the candidate solutions is based on the result of non-deterministic battles (and environmental interactions) against other bots,whose outcome depends on random draws as well as on the opponents'actions.Therefore,the proposed GA is dealing with a noisy fitness function.After analysing the effects of the noisy fitness,we conclude that tackling randomness via repeated combats and reevaluations reduces this effect and makes the GA a highly valuable approach for solving this problem.
Du, Tien Duc; Ngo-Duc, Thanh; Kieu, Chanh
2017-07-01
This study presents an approach to assimilate tropical cyclone (TC) real-time reports and the University of Wisconsin-Cooperative Institute for Meteorological Satellite Studies (CIMSS) Atmospheric Motion Vectors (AMV) data into the Weather Research and Forecasting (WRF) model for TC forecast applications. Unlike current methods in which TC real-time reports are used to either generate a bogus vortex or spin up a model initial vortex, the proposed approach ingests the TC real-time reports through blending a dynamically consistent synthetic vortex structure with the CIMSS-AMV data. The blended dataset is then assimilated into the WRF initial condition, using the local ensemble transform Kalman filter (LETKF) algorithm. Retrospective experiments for a number of TC cases in the northwestern Pacific basin during 2013-2014 demonstrate that this approach could effectively increase both the TC circulation and enhance the large-scale environment that the TCs are embedded in. Further evaluation of track and intensity forecast errors shows that track forecasts benefit more from improvement in the large-scale flow at 4-5-day lead times, whereas the intensity improvement is minimal. While the difference between the track and intensity improvement could be due to a specific model configuration, this result appears to be consistent with the recent reports of insignificant impacts of inner core data assimilation in operational TC models at the long range of 4-5 days. The new approach will be most beneficial for future regional TC models that are directly initialized from very high-resolution global models whose storm initial locations are sufficiently accurate at the initial analysis that there is no need to carry out any artificial vortex removal or filtering steps.
Evaluation of Real-Time Hand Motion Tracking Using a Range Camera and the Mean-Shift Algorithm
Lahamy, H.; Lichti, D.
2011-09-01
Several sensors have been tested for improving the interaction between humans and machines including traditional web cameras, special gloves, haptic devices, cameras providing stereo pairs of images and range cameras. Meanwhile, several methods are described in the literature for tracking hand motion: the Kalman filter, the mean-shift algorithm and the condensation algorithm. In this research, the combination of a range camera and the simple version of the mean-shift algorithm has been evaluated for its capability for hand motion tracking. The evaluation was assessed in terms of position accuracy of the tracking trajectory in x, y and z directions in the camera space and the time difference between image acquisition and image display. Three parameters have been analyzed regarding their influence on the tracking process: the speed of the hand movement, the distance between the camera and the hand and finally the integration time of the camera. Prior to the evaluation, the required warm-up time of the camera has been measured. This study has demonstrated the suitability of the range camera used in combination with the mean-shift algorithm for real-time hand motion tracking but for very high speed hand movement in the traverse plane with respect to the camera, the tracking accuracy is low and requires improvement.
EVALUATION OF REAL-TIME HAND MOTION TRACKING USING A RANGE CAMERA AND THE MEAN-SHIFT ALGORITHM
H. Lahamy
2012-09-01
Full Text Available Several sensors have been tested for improving the interaction between humans and machines including traditional web cameras, special gloves, haptic devices, cameras providing stereo pairs of images and range cameras. Meanwhile, several methods are described in the literature for tracking hand motion: the Kalman filter, the mean-shift algorithm and the condensation algorithm. In this research, the combination of a range camera and the simple version of the mean-shift algorithm has been evaluated for its capability for hand motion tracking. The evaluation was assessed in terms of position accuracy of the tracking trajectory in x, y and z directions in the camera space and the time difference between image acquisition and image display. Three parameters have been analyzed regarding their influence on the tracking process: the speed of the hand movement, the distance between the camera and the hand and finally the integration time of the camera. Prior to the evaluation, the required warm-up time of the camera has been measured. This study has demonstrated the suitability of the range camera used in combination with the mean-shift algorithm for real-time hand motion tracking but for very high speed hand movement in the traverse plane with respect to the camera, the tracking accuracy is low and requires improvement.
Kizhner, Semion; Hunter, Stanley D.; Hanu, Andrei R.; Sheets, Teresa B.
2016-01-01
Richard O. Duda and Peter E. Hart of Stanford Research Institute in [1] described the recurring problem in computer image processing as the detection of straight lines in digitized images. The problem is to detect the presence of groups of collinear or almost collinear figure points. It is clear that the problem can be solved to any desired degree of accuracy by testing the lines formed by all pairs of points. However, the computation required for n=NxM points image is approximately proportional to n2 or O(n2), becoming prohibitive for large images or when data processing cadence time is in milliseconds. Rosenfeld in [2] described an ingenious method due to Hough [3] for replacing the original problem of finding collinear points by a mathematically equivalent problem of finding concurrent lines. This method involves transforming each of the figure points into a straight line in a parameter space. Hough chose to use the familiar slope-intercept parameters, and thus his parameter space was the two-dimensional slope-intercept plane. A parallel Hough transform running on multi-core processors was elaborated in [4]. There are many other proposed methods of solving a similar problem, such as sampling-up-the-ramp algorithm (SUTR) [5] and algorithms involving artificial swarm intelligence techniques [6]. However, all state-of-the-art algorithms lack in real time performance. Namely, they are slow for large images that require performance cadence of a few dozens of milliseconds (50ms). This problem arises in spaceflight applications such as near real-time analysis of gamma ray measurements contaminated by overwhelming amount of traces of cosmic rays (CR). Future spaceflight instruments such as the Advanced Energetic Pair Telescope instrument (AdEPT) [7-9] for cosmos gamma ray survey employ large detector readout planes registering multitudes of cosmic ray interference events and sparse science gamma ray event traces' projections. The AdEPT science of interest is in the
X-LUNA: Extending Free/Open Source Real Time Executive for On-Board Space Applications
Braga, P.; Henriques, L.; Zulianello, M.
2008-08-01
In this paper we present xLuna, a system based on the RTEMS [1] Real-Time Operating System that is able to run on demand a GNU/Linux Operating System [2] as RTEMS' lowest priority task. Linux runs in user-mode and in a different memory partition. This allows running Hard Real-Time tasks and Linux applications on the same system sharing the Hardware resources while keeping a safe isolation and the Real-Time characteristics of RTEMS. Communication between both Systems is possible through a loose coupled mechanism based on message queues. Currently only SPARC LEON2 processor with Memory Management Unit (MMU) is supported. The advantage in having two isolated systems is that non critical components are quickly developed or simply ported reducing time-to-market and budget.
Lu, Zhonghua; Arikatla, Venkata S; Han, Zhongqing; Allen, Brian F; De, Suvranu
2014-12-01
High-frequency electricity is used in the majority of surgical interventions. However, modern computer-based training and simulation systems rely on physically unrealistic models that fail to capture the interplay of the electrical, mechanical and thermal properties of biological tissue. We present a real-time and physically realistic simulation of electrosurgery by modelling the electrical, thermal and mechanical properties as three iteratively solved finite element models. To provide subfinite-element graphical rendering of vaporized tissue, a dual-mesh dynamic triangulation algorithm based on isotherms is proposed. The block compressed row storage (BCRS) structure is shown to be critical in allowing computationally efficient changes in the tissue topology due to vaporization. We have demonstrated our physics-based electrosurgery cutting algorithm through various examples. Our matrix manipulation algorithms designed for topology changes have shown low computational cost. Our simulator offers substantially greater physical fidelity compared to previous simulators that use simple geometry-based heat characterization. Copyright © 2013 John Wiley & Sons, Ltd.
Lee, Hyoki; Park, Jonguk; Kim, Hojoong; Lee, Kyoung-Joung
2016-12-01
We developed a rule-based algorithm for automatic real-time detection of sleep apnea and hypopnea events using a nasal pressure signal. Our basic premise was that the performance of our new algorithm using the nasal pressure signal would be comparable to that using other sensors as well as manual annotation labeled by a technician on polysomnography study. We investigated fifty patients with sleep apnea-hypopnea syndrome (age: 56.8 ± 10.5 years, apnea-hypopnea index (AHI): 36.2 ± 18.1/h) during full night PSG recordings at the sleep center. The algorithm was comprised of pre-processing with a median filter, amplitude computation and apnea-hypopnea detection parts. We evaluated the performance of the algorithm a confusion matric for each event and statistical analyses for AHI. Our evaluation achieved a good performance, with a sensitivity of 86.4 %, and a positive predictive value of 84.5 % for detection of apnea and hypopnea regardless of AHI severity. Our results indicated a high correlation with the manually labeled apnea-hypopnea events during PSG, with a correlation coefficient of r = 0.94 (p mean difference of -2.9 ± 11.6 per hour. The proposed new algorithm could provide significant clinical and computational insights to design a PSG analysis system and a continuous positive airway pressure (CPAP) device for screening sleep quality related in patients with sleep apnea-hypopnea syndrome.
Hasegawa, Taisuke
2016-11-07
We propose a novel molecular dynamics (MD) algorithm for approximately dealing with a nuclear quantum dynamics in a real-time MD simulation. We have found that real-time dynamics of the ensemble of classical particles acquires quantum nature by introducing a constant quantum mechanical uncertainty constraint on its classical dynamics. The constant uncertainty constraint is handled by the Lagrange multiplier method and implemented into a conventional MD algorithm. The resulting constant uncertainty molecular dynamics (CUMD) is applied to the calculation of quantum position autocorrelation functions on quartic and Morse potentials. The test calculations show that CUMD gives better performance than ring-polymer MD because of the inclusion of the quantum zero-point energy during real-time evolution as well as the quantum imaginary-time statistical effect stored in an initial condition. The CUMD approach will be a possible starting point for new real-time quantum dynamics simulation in condensed phase.
Hasegawa, Taisuke
2016-11-01
We propose a novel molecular dynamics (MD) algorithm for approximately dealing with a nuclear quantum dynamics in a real-time MD simulation. We have found that real-time dynamics of the ensemble of classical particles acquires quantum nature by introducing a constant quantum mechanical uncertainty constraint on its classical dynamics. The constant uncertainty constraint is handled by the Lagrange multiplier method and implemented into a conventional MD algorithm. The resulting constant uncertainty molecular dynamics (CUMD) is applied to the calculation of quantum position autocorrelation functions on quartic and Morse potentials. The test calculations show that CUMD gives better performance than ring-polymer MD because of the inclusion of the quantum zero-point energy during real-time evolution as well as the quantum imaginary-time statistical effect stored in an initial condition. The CUMD approach will be a possible starting point for new real-time quantum dynamics simulation in condensed phase.
Bukhari, W; Hong, S-M
2016-03-01
The prediction as well as the gating of respiratory motion have received much attention over the last two decades for reducing the targeting error of the radiation treatment beam due to respiratory motion. In this article, we present a real-time algorithm for predicting respiratory motion in 3D space and realizing a gating function without pre-specifying a particular phase of the patient's breathing cycle. The algorithm, named EKF-GPRN(+) , first employs an extended Kalman filter (EKF) independently along each coordinate to predict the respiratory motion and then uses a Gaussian process regression network (GPRN) to correct the prediction error of the EKF in 3D space. The GPRN is a nonparametric Bayesian algorithm for modeling input-dependent correlations between the output variables in multi-output regression. Inference in GPRN is intractable and we employ variational inference with mean field approximation to compute an approximate predictive mean and predictive covariance matrix. The approximate predictive mean is used to correct the prediction error of the EKF. The trace of the approximate predictive covariance matrix is utilized to capture the uncertainty in EKF-GPRN(+) prediction error and systematically identify breathing points with a higher probability of large prediction error in advance. This identification enables us to pause the treatment beam over such instances. EKF-GPRN(+) implements a gating function by using simple calculations based on the trace of the predictive covariance matrix. Extensive numerical experiments are performed based on a large database of 304 respiratory motion traces to evaluate EKF-GPRN(+) . The experimental results show that the EKF-GPRN(+) algorithm reduces the patient-wise prediction error to 38%, 40% and 40% in root-mean-square, compared to no prediction, at lookahead lengths of 192 ms, 384 ms and 576 ms, respectively. The EKF-GPRN(+) algorithm can further reduce the prediction error by employing the gating
Hand-guided 3D surface acquisition by combining simple light sectioning with real-time algorithms
Arold, Oliver; Willomitzer, Florian; Häusler, Gerd
2014-01-01
Precise 3D measurements of rigid surfaces are desired in many fields of application like quality control or surgery. Often, views from all around the object have to be acquired for a full 3D description of the object surface. We present a sensor principle called "Flying Triangulation" which avoids an elaborate "stop-and-go" procedure. It combines a low-cost classical light-section sensor with an algorithmic pipeline. A hand-guided sensor captures a continuous movie of 3D views while being moved around the object. The views are automatically aligned and the acquired 3D model is displayed in real time. In contrast to most existing sensors no bandwidth is wasted for spatial or temporal encoding of the projected lines. Nor is an expensive color camera necessary for 3D acquisition. The achievable measurement uncertainty and lateral resolution of the generated 3D data is merely limited by physics. An alternating projection of vertical and horizontal lines guarantees the existence of corresponding points in successi...
Engel, Klaus; Kniss, Joe; Rezk-Salama, Christof; Weiskopf, Daniel
2006-01-01
Based on course notes of SIGGRAPH course teaching techniques for real-time rendering of volumetric data and effects; covers both applications in scientific visualization and real-time rendering. Starts with the basics (texture-based ray casting) and then improves and expands the algorithms incrementally. Book includes source code, algorithms, diagrams, and rendered graphics.
A real-time classification algorithm for EEG-based BCI driven by self-induced emotions.
Iacoviello, Daniela; Petracca, Andrea; Spezialetti, Matteo; Placidi, Giuseppe
2015-12-01
The aim of this paper is to provide an efficient, parametric, general, and completely automatic real time classification method of electroencephalography (EEG) signals obtained from self-induced emotions. The particular characteristics of the considered low-amplitude signals (a self-induced emotion produces a signal whose amplitude is about 15% of a really experienced emotion) require exploring and adapting strategies like the Wavelet Transform, the Principal Component Analysis (PCA) and the Support Vector Machine (SVM) for signal processing, analysis and classification. Moreover, the method is thought to be used in a multi-emotions based Brain Computer Interface (BCI) and, for this reason, an ad hoc shrewdness is assumed. The peculiarity of the brain activation requires ad-hoc signal processing by wavelet decomposition, and the definition of a set of features for signal characterization in order to discriminate different self-induced emotions. The proposed method is a two stages algorithm, completely parameterized, aiming at a multi-class classification and may be considered in the framework of machine learning. The first stage, the calibration, is off-line and is devoted at the signal processing, the determination of the features and at the training of a classifier. The second stage, the real-time one, is the test on new data. The PCA theory is applied to avoid redundancy in the set of features whereas the classification of the selected features, and therefore of the signals, is obtained by the SVM. Some experimental tests have been conducted on EEG signals proposing a binary BCI, based on the self-induced disgust produced by remembering an unpleasant odor. Since in literature it has been shown that this emotion mainly involves the right hemisphere and in particular the T8 channel, the classification procedure is tested by using just T8, though the average accuracy is calculated and reported also for the whole set of the measured channels. The obtained
Spranger, K; Capelli, C; Bosi, G M; Schievano, S; Ventikos, Y
2015-08-15
In this paper, we perform a comparative analysis between two computational methods for virtual stent deployment: a novel fast virtual stenting method, which is based on a spring-mass model, is compared with detailed finite element analysis in a sequence of in silico experiments. Given the results of the initial comparison, we present a way to optimise the fast method by calibrating a set of parameters with the help of a genetic algorithm, which utilises the outcomes of the finite element analysis as a learning reference. As a result of the calibration phase, we were able to substantially reduce the force measure discrepancy between the two methods and validate the fast stenting method by assessing the differences in the final device configurations.
Spranger, K.; Capelli, C.; Bosi, G.M.; Schievano, S.; Ventikos, Y.
2015-01-01
In this paper, we perform a comparative analysis between two computational methods for virtual stent deployment: a novel fast virtual stenting method, which is based on a spring–mass model, is compared with detailed finite element analysis in a sequence of in silico experiments. Given the results of the initial comparison, we present a way to optimise the fast method by calibrating a set of parameters with the help of a genetic algorithm, which utilises the outcomes of the finite element analysis as a learning reference. As a result of the calibration phase, we were able to substantially reduce the force measure discrepancy between the two methods and validate the fast stenting method by assessing the differences in the final device configurations. PMID:26664007
Zaccheo, T. S.; Pernini, T.; Botos, C.; Dobler, J. T.; Blume, N.
2015-12-01
The Greenhouse gas Laser Imaging Tomography Experiment (GreenLITE) combines real-time differential Laser Absorption Spectroscopy (LAS) measurements with a lightweight web-based data acquisition and product generation system to provide autonomous 24/7 monitoring of CO2. The current GreenLITE system is comprised of two transceivers and a series of retro-reflectors that continuously measure the differential transmission over a user-defined set of intersecting line-of-site paths or "chords" that form the plane of interest. These observations are first combined with in situ surface measurements of temperature (T), pressure (P) and relative humidity (RH) to compute the integrated CO2 mixing ratios based on an iterative radiative transfer modeling approach. The retrieved CO2 mixing ratios are then grouped based on observation time and employed in a sparse sample reconstruction method to provide a tomographic- like representation of the 2-D distribution of CO2 over the field of interest. This reconstruction technique defines the field of interest as a set of idealized plumes whose integrated values best match the observations. The GreenLITE system has been deployed at two primary locations; 1) the Zero Emissions Research and Technology (ZERT) center in Bozeman, Montana, in Aug-Sept 2014, where more than 200 hours of data were collected over a wide range of environmental conditions while utilizing a controlled release of CO2 into a segmented underground pipe, and 2) continuously at a carbon sequestration test facility in Feb-Aug 2015. The system demonstrated the ability to identify persistent CO2 sources at the ZERT test facility and showed strong correlation with an independent measurement using a LI-COR based system. Here we describe the measurement approach, algorithm design and extended study results.
Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Hekkert, Tiago; Carvalho, Bernardo B.
2014-03-15
Highlights: • All real-time diagnostics and actuators were integrated in the same control platform. • A 100 μs control cycle was achieved under the MARTe framework. • Time-windows based control with several event-driven control strategies implemented. • AC discharges with exception handling on iron core flux saturation. • An HTML discharge configuration was developed for configuring the MARTe system. - Abstract: The ISTTOK tokamak was upgraded with a plasma control system based on the Advanced Telecommunications Computing Architecture (ATCA) standard. This control system was designed to improve the discharge stability and to extend the operational space to the alternate plasma current (AC) discharges as part of the ISTTOK scientific program. In order to accomplish these objectives all ISTTOK diagnostics and actuators relevant for real-time operation were integrated in the control system. The control system was programmed in C++ over the Multi-threaded Application Real-Time executor (MARTe) which provides, among other features, a real-time scheduler, an interrupt handler, an intercommunications interface between code blocks and a clearly bounded interface with the external devices. As a complement to the MARTe framework, the BaseLib2 library provides the foundations for the data, code introspection and also a Hypertext Transfer Protocol (HTTP) server service. Taking advantage of the modular nature of MARTe, the algorithms of each diagnostic data processing, discharge timing, context switch, control and actuators output reference generation, run on well-defined blocks of code named Generic Application Module (GAM). This approach allows reusability of the code, simplified simulation, replacement or editing without changing the remaining GAMs. The ISTTOK control system GAMs run sequentially each 100 μs cycle on an Intel{sup ®} Q8200 4-core processor running at 2.33 GHz located in the ATCA crate. Two boards (inside the ATCA crate) with 32 analog
Novotny, M.A.; Guerra, M.; Raedt, H. De; Michielsen, K.; Jin, F.
2012-01-01
An efficient algorithm for the computation of the real-time dependence of a single quantum spin-1/2 coupled to a specific set of quantum spin-1/2 baths is presented. The specific spin baths have couplings only with the spin operators Sx between bath spins and the central spin. We calculate spin expe
Badr, Salah M.; Bruztman, Donald P.; Nelson, Michael L.; Byrnes, Ronald Benton
1992-01-01
This paper presents an introduction to the basic issues involved in real-time systems. Both real-time operating sys and real-time programming languages are explored. Concurrent programming and process synchronization and communication are also discussed. The real-time requirements of the Naval Postgraduate School Autonomous Under Vehicle (AUV) are then examined. Autonomous underwater vehicle (AUV), hard real-time system, real-time operating system, real-time programming language, real-time sy...
Adedeji, K
2016-09-01
Full Text Available of pipelines transporting this resource needs to be reduced. This paper briefly elaborates on work in progress employing wireless sensor networks (WSNs) to an improved negative pressure wave method for real-time leakage monitoring of a water pipeline network....
A Fast Algorithm for Real-Time MPEG-2 Audio Coder%MPEG-2音频压缩编码的一种快速算法
马欣; 刘常澍; 李文元; 张毓忠
2004-01-01
A real-time MPEG-2 layer 1&2 audio coder realized on one TMS320C31 is developed. In order to realize the coder real-time, a new fast algorithms for MPEG-2 audio sub-band analysis filter is presented. The algorithm can reduce calculation work of sub-band analysis to 1/5 of that processed by algorithm ISO/IEC 11172-3 recommended. Software and hardware simulation of the algorithm is made. Through a simulator the programs are loaded on a TMS320C31. The MPEG audio coder is realized in real time.%采用一片美国TI公司的数字信号处理芯片TMS320C31实现了MPEG-2音频Layer-1、2实时压缩编解码器.为了达到实时的目的,对ISO/IEC 11172-3建议的子带分析方案提出了一种新的快速算法.采用该快速算法,可以使子带分析的运算量降低5倍.仿真实验表明,采用快速算法后,用一片TMS320C31可以达到实时编码.
Jackson, Christopher Robert
"Lucky-region" fusion (LRF) is a synthetic imaging technique that has proven successful in enhancing the quality of images distorted by atmospheric turbulence. The LRF algorithm selects sharp regions of an image obtained from a series of short exposure frames, and fuses the sharp regions into a final, improved image. In previous research, the LRF algorithm had been implemented on a PC using the C programming language. However, the PC did not have sufficient sequential processing power to handle real-time extraction, processing and reduction required when the LRF algorithm was applied to real-time video from fast, high-resolution image sensors. This thesis describes two hardware implementations of the LRF algorithm to achieve real-time image processing. The first was created with a VIRTEX-7 field programmable gate array (FPGA). The other developed using the graphics processing unit (GPU) of a NVIDIA GeForce GTX 690 video card. The novelty in the FPGA approach is the creation of a "black box" LRF video processing system with a general camera link input, a user controller interface, and a camera link video output. We also describe a custom hardware simulation environment we have built to test the FPGA LRF implementation. The advantage of the GPU approach is significantly improved development time, integration of image stabilization into the system, and comparable atmospheric turbulence mitigation.
Byung-eun LEE; Thanh-binh NGUYEN; Sun-tae CHUNG
2010-01-01
Foreground moving object detection is an important pocess in various computer vision applicatipons such as intelligent visual sur-veillance,HCI,object-based video compression,etc.One of the most successful moving object detection algorithms is based on Adaptive Gaussian Mixture Model (AGMM).Although AGMM-based object detection shows very good performance with respect to object detection accuracy,AGMM is very complex model requiring lots of floating-point arithmetic so that it should pay for expensive computational cost.Thus,direa implementation of the AGMM-based object detec-tion for embedded DSPs without floating-point arithmetic HW support cannot satisfy the real-time processing requirement.This paper pre-sents a navel real-time implementation of adaptive Gaussian mixture model-based moving object detection algorithm for fixed-point DSPs.In the proposed implementation,in addition to changes of data types into fixed- point ones,magnification of the Gaussian distribution tech nique is introduced so that the integer and fixed-point arithmetic can be easily and consistently utilized instead of real number and floating-point arithmetic in processing of AGMM algorithm.Experimental re-sults shows that the proposed implementation have a high potential in real-time applications.
REAL-TIME FACE TRACKING ALGORITHM BASED ON ONLINE INCREMENTAL LEARNING%基于在线增量学习的实时人脸跟踪算法
包芳; 张炎凯; 王士同
2016-01-01
提出基于在线增量式极端随机森林分类器的实时人脸跟踪算法。算法用在线极端随机森林分类器实现基于检测的跟踪，并结合动态目标框架和 P-N 学习矫正检测的错误。实验结果表明，该算法能够在不确定背景下对任意人脸实现较长时间段内的稳定快速的实时跟踪，并能有效排除背景等的干扰，效果较好。%The paper proposes a real-time face tracking algorithm,which is based on online incremental extremely random forests classifier.The algorithm achieves detection-based real-time tracking using online incremental extremely random forests classifier,and combines dynamic target framework and P-N learning to correct detection errors.Experimental results show,the proposed algorithm can realise fast and stable real-time tracking for any face in a longer period under uncertain background,and can effectively overcome interferences such as background with preferable effect.
IMM Iterated Extended Particle Filter Algorithm
Yang Wan; Shouyong Wang; Xing Qin
2013-01-01
In order to solve the tracking problem of radar maneuvering target in nonlinear system model and non-Gaussian noise background, this paper puts forward one interacting multiple model (IMM) iterated extended particle filter algorithm (IMM-IEHPF). The algorithm makes use of multiple modes to model the target motion form to track any maneuvering target and each mode uses iterated extended particle filter (IEHPF) to deal with the state estimation problem of nonlinear non-Gaussian system. IEH...
Extended PGA for Range Migration Algorithms
Rossum, W.L. van; Otten, M.P.G.; Bree, R.J.P. van
2006-01-01
The Phase Gradient Autofocus (PGA) algorithm is extended to work for synthetic aperture radar (SAR) spotlight images processed with range migration (ω-k) algorithms. Several pre-processing steps are proposed for aligning the range-compressed phase-history data needed for successful autofocusing of
Peng Lin
2014-01-01
Full Text Available This paper investigates the feasibility of a real-time tunnel location-based services (LBS system to provide workers’ safety protection and various services in concrete dam site. In this study, received signal strength- (RSS- based location using fingerprinting algorithm and artificial neural network (ANN risk assessment is employed for position analysis. This tunnel LBS system achieves an online, real-time, intelligent tracking identification feature, and the on-site running system has many functions such as worker emergency call, track history, and location query. Based on ANN with a strong nonlinear mapping, and large-scale parallel processing capabilities, proposed LBS system is effective to evaluate the risk management on worker safety. The field implementation shows that the proposed location algorithm is reliable and accurate (3 to 5 meters enough for providing real-time positioning service. The proposed LBS system is demonstrated and firstly applied to the second largest hydropower project in the world, to track workers on tunnel site and assure their safety. The results show that the system is simple and easily deployed.
PNL super-resolution algorithm for PMMW imaging in real-time%无源毫米波实时成像PNL超分辨算法
姜正茂; 杨建宇; 李良超; 郑鑫
2012-01-01
投影Landweber (projected Landweber,PL)算法具有良好的频谱外推能力,能够应用于低信噪比降晰图像,是一种适合无源毫米波成像的超分辨算法.但其缺点是收敛速度缓慢,运算量不稳定,难以满足实时性要求.针对实时性问题,提出一种投影Newton-Landweber (projected Newton-Landweber,PNL)超分辨算法,首先使用Newton求逆法得到粗恢复图像,然后运用PL算法对图像做精细恢复.实验结果表明,该算法显著提高了收敛速度,图像恢复质量接近PL算法的性能.%The projected Landweber (PL) algorithm is competent for passive millimeter wave (PMMW) imaging for its spectrum extrapolation performance and low signal to noise ratio images processing ability, however, the slow speed of convergence and the computation instability limit its applications in real-time. A projected Newton-Landweber (PNL) algorithm is proposed to achieve real-time ability on the basis of the PL algorithm. Firstly, a fast Newton inversion algorithm is introduced to get coarse image recovery. Then the PL algorithm is used to get refined image recovery. Experimental results demonstrate that the performance of the PNL algorithm approaches that of the PL algorithm, moreover the computation is stable and far less than the PL algorithm.
On-line Detection of Gas Pipeline Based on the Real-Time Algorithm and Network Technology with Robot
YAN Bo; YAN Guo-zheng; DING Guo-qing; ZHOU Bing; FU Xi-guang; ZUO Jian-yong
2004-01-01
The detection system integrates control technology, network technology, video encoding and decoding, video transmiss-ion, multi-single chip microcomputer communication, dat-abase technology, computer software and robot technology. The robot can adaptively adjust its status according to diameter (from 400 mm to 650 mm) of pipeline. The maximum detection distance is up to 1 000 m. The method of video coding in the system is based on fractal transformation. The experiments show that the coding scheme is fast and good PSNR. The precision of on-line detection is up to 3% thickness of pipeline wall. The robot can also have a high precision of location up to 0.03 m. The control method is based on network and characterized by on-line and real-time. The experiment in real gas pipeline shows that the performance of the detection system is good.
GPS/BDS的RTK定位算法研究%Real-Time Kinematic Positioning Algorithm of GPS/BDS
王世进; 秘金钟; 李得海; 祝会忠
2014-01-01
针对附加模糊度参数的Kalman滤波函数模型和随机模型,提出了一种确定实时动态(real-time kinematic,RTK)定位中Kalman滤波参数的方法.利用该算法,采用自编的GPS/BDS RTK定位程序处理了实测的GPS/BDS短基线数据,对比和分析了GPS、BDS、GPS/BDS三种RTK定位组合模式下的定位精度水平.在短基线的情况下,GPS/BDS的RTK定位精度相对于GPS或者BDS没有明显提高,但是得到固定解所需的时间明显减少.
Alves, D.; Coelho, R.; JET-EFDA Contributors
2013-08-01
The real-time tracking of instantaneous quantities such as frequency, amplitude, and phase of components immerse in noisy signals has been a common problem in many scientific and engineering fields such as power systems and delivery, telecommunications, and acoustics for the past decades. In magnetically confined fusion research, extracting this sort of information from magnetic signals can be of valuable assistance in, for instance, feedback control of detrimental magnetohydrodynamic modes and disruption avoidance mechanisms by monitoring instability growth or anticipating mode-locking events. This work is focused on nonlinear Kalman filter based methods for tackling this problem. Similar methods have already proven their merits and have been successfully employed in this scientific domain in applications such as amplitude demodulation for the motional Stark effect diagnostic. In the course of this work, three approaches are described, compared, and discussed using magnetic signals from the Joint European Torus tokamak plasma discharges for benchmarking purposes.
A Real-Time De-Noising Algorithm for E-Noses in a Wireless Sensor Network
Yi Chai
2009-02-01
Full Text Available A wireless e-nose network system is developed for the special purpose of monitoring odorant gases and accurately estimating odor strength in and around livestock farms. This system is to simultaneously acquire accurate odor strength values remotely at various locations, where each node is an e-nose that includes four metal-oxide semiconductor (MOS gas sensors. A modified Kalman filtering technique is proposed for collecting raw data and de-noising based on the output noise characteristics of those gas sensors. The measurement noise variance is obtained in real time by data analysis using the proposed slip windows average method. The optimal system noise variance of the filter is obtained by using the experiments data. The Kalman filter theory on how to acquire MOS gas sensors data is discussed. Simulation results demonstrate that the proposed method can adjust the Kalman filter parameters and significantly reduce the noise from the gas sensors.
Multifunction Vehicle Bus Arbitration Real-Time Scheduling Algorithm%多功能车辆总线事件仲裁实时调度算法
王宏志; 徐进权; 胡黄水
2015-01-01
针对列车通信采用多功能车辆总线(multifunction vehicle bus,MVB)网络传输数据的实时性要求,提出一种动态优先级时间片轮询算法。该算法根据非周期数据的优先级进行仲裁调度,通过优化算法复杂度、减小数据等待延时和阻塞延时,解决了 MVB 网络实时性的问题。并对 MVB 总线非周期数据的实时性、公平性等进行仿真分析,结果表明,该算法能提高 MVB 总线非周期数据传输的实时性与公平性,可满足列车通信网络标准 ICE61375-1对实时性的要求。%According to the train communication network and multifunction vehicle bus network real-time transport protocols, the authors presented a dynamic priority round-Robin algorithm. Multifunction vehicle bus (MVB ) is used widely in train communication networks to realize interconnection among different devices.It must meet the real-time performance while multifunction vehicle bus is used to transmit data according to the ICE61375-1.In the multifunction vehicle bus network,the delay among transmission equipments mainly includes waiting to be sent delay and transmitting the data packet delay and so on.Based on the priority of non-periodic data to achieve arbitration scheduling,the algorithm can improve the real-time performance of multifunction vehicle bus network to transmit the non-periodic data by means of optimizing the complexity of algorithm and reducing waiting delay and blocking delay.The simulation analysis shows that the algorithm can improve the real-time performance and fairness performance of MVB transmission.At the same time, the algorithm also meets the requirements of the ICE61375-1.
Changhao Piao
2015-01-01
Full Text Available A novel cell-balancing algorithm which was used for cell balancing of battery management system (BMS was proposed in this paper. Cell balancing algorithm is a key technology for lithium-ion battery pack in the electric vehicle field. The distance-based outlier detection algorithm adopted two characteristic parameters (voltage and state of charge to calculate each cell’s abnormal value and then identified the unbalanced cells. The abnormal and normal type of battery cells were acquired by online clustering strategy and bleeding circuits (R = 33 ohm were used to balance the abnormal cells. The simulation results showed that with the proposed balancing algorithm, the usable capacity of the battery pack increased by 0.614 Ah (9.5% compared to that without balancing.
Brown, Douglas (Sandia National Laboratories, Livermore, CA); Gray, Genetha Anne (Sandia National Laboratories, Livermore, CA)
2005-10-01
Due to the nature of many infectious agents, such as anthrax, symptoms may either take several days to manifest or resemble those of less serious illnesses leading to misdiagnosis. Thus, bioterrorism attacks that include the release of such agents are particularly dangerous and potentially deadly. For this reason, a system is needed for the quick and correct identification of disease outbreaks. The Real-time Outbreak Disease Surveillance System (RODS), initially developed by Carnegie Mellon University and the University of Pittsburgh, was created to meet this need. The RODS software implements different classifiers for pertinent health surveillance data in order to determine whether or not an outbreak has occurred. In an effort to improve the capability of RODS at detecting outbreaks, we incorporate a data fusion method. Data fusion is used to improve the results of a single classification by combining the output of multiple classifiers. This paper documents the first stages of the development of a data fusion system that can combine the output of the classifiers included in RODS.
A Novel Real-Time DDoS Attack Detection Mechanism Based on MDRA Algorithm in Big Data
Bin Jia
2016-01-01
Full Text Available In the wake of the rapid development and wide application of information technology and Internet, our society has come into the information explosion era. Meanwhile, it brings in new and severe challenges to the field of network attack behavior detection due to the explosive growth and high complexity of network traffic. Therefore, an effective and efficient detection mechanism that can detect attack behavior from large scale of network traffic plays an important role. In this paper, we focus on how to distinguish the attack traffic from normal data flows in Big Data and propose a novel real-time DDoS attack detection mechanism based on Multivariate Dimensionality Reduction Analysis (MDRA. In this mechanism, we first reduce the dimensionality of multiple characteristic variables in a network traffic record by Principal Component Analysis (PCA. Then, we analyze the correlation of the lower dimensional variables. Finally, the attack traffic can be differentiated from the normal traffic by MDRA and Mahalanobis distance (MD. Compared with previous research methods, our experimental results show that higher precision rate is achieved and it approximates to 100% in True Negative Rate (TNR for detection; CPU computing time is one-eightieth and memory resource consumption is one-third of the previous detection method based on Multivariate Correlation Analysis (MCA; computing complexity is constant.
Andersen, C.E.; Marckmann, C.J.; Aznar, Marianne
2006-01-01
Although the radioluminescence (RL) signal from optical fibre Al2O3:C dosemeters used in medical applications is essentially proportional to dose rate, the crystals used so far are imperfect in the sense that their RL sensitivity changes with accumulated dose. A computational algorithm has been...... to the treatment planning system. RL signals from Al2O3:C can be used for real-time dose rate measurements with a time resolution of similar to 0.1 s and a spatial resolution only limited by the size of the detector (
Laban, Shaban; El-Desouky, Aly
2013-04-01
The monitoring of real-time systems is a challenging and complicated process. So, there is a continuous need to improve the monitoring process through the use of new intelligent techniques and algorithms for detecting exceptions, anomalous behaviours and generating the necessary alerts during the workflow monitoring of such systems. The interval-based or period-based theorems have been discussed, analysed, and used by many researches in Artificial Intelligence (AI), philosophy, and linguistics. As explained by Allen, there are 13 relations between any two intervals. Also, there have also been many studies of interval-based temporal reasoning and logics over the past decades. Interval-based theorems can be used for monitoring real-time interval-based data processing. However, increasing the number of processed intervals makes the implementation of such theorems a complex and time consuming process as the relationships between such intervals are increasing exponentially. To overcome the previous problem, this paper presents a Rule-based Interval State Machine Algorithm (RISMA) for processing, monitoring, and analysing the behaviour of interval-based data, received from real-time sensors. The proposed intelligent algorithm uses the Interval State Machine (ISM) approach to model any number of interval-based data into well-defined states as well as inferring them. An interval-based state transition model and methodology are presented to identify the relationships between the different states of the proposed algorithm. By using such model, the unlimited number of relationships between similar large numbers of intervals can be reduced to only 18 direct relationships using the proposed well-defined states. For testing the proposed algorithm, necessary inference rules and code have been designed and applied to the continuous data received in near real-time from the stations of International Monitoring System (IMS) by the International Data Centre (IDC) of the Preparatory
Nepal, Kumud; Fine, Adam; Imam, Nabil; Pietrocola, David; Robertson, Neil; Ahlgren, David J.
2009-01-01
Q is an unmanned ground vehicle designed to compete in the Autonomous and Navigation Challenges of the AUVSI Intelligent Ground Vehicle Competition (IGVC). Built on a base platform of a modified PerMobil Trax off-road wheel chair frame, and running off a Dell Inspiron D820 laptop with an Intel t7400 Core 2 Duo Processor, Q gathers information from a SICK laser range finder (LRF), video cameras, differential GPS, and digital compass to localize its behavior and map out its navigational path. This behavior is handled by intelligent closed loop speed control and robust sensor data processing algorithms. In the Autonomous challenge, data taken from two IEEE 1394 cameras and the LRF are integrated and plotted on a custom-defined occupancy grid and converted into a histogram which is analyzed for openings between obstacles. The image processing algorithm consists of a series of steps involving plane extraction, normalizing of the image histogram for an effective dynamic thresholding, texture and morphological analysis and particle filtering to allow optimum operation at varying ambient conditions. In the Navigation Challenge, a modified Vector Field Histogram (VFH) algorithm is combined with an auto-regressive path planning model for obstacle avoidance and better localization. Also, Q features the Joint Architecture for Unmanned Systems (JAUS) Level 3 compliance. All algorithms are developed and implemented using National Instruments (NI) hardware and LabVIEW software. The paper will focus on explaining the various algorithms that make up Q's intelligence and the different ways and modes of their implementation.
Cippitelli, Enea; Gasparrini, Samuele; Spinsante, Susanna; Gambi, Ennio
2015-01-14
The Microsoft Kinect sensor has gained attention as a tool for gait analysis for several years. Despite the many advantages the sensor provides, however, the lack of a native capability to extract joints from the side view of a human body still limits the adoption of the device to a number of relevant applications. This paper presents an algorithm to locate and estimate the trajectories of up to six joints extracted from the side depth view of a human body captured by the Kinect device. The algorithm is then applied to extract data that can be exploited to provide an objective score for the "Get Up and Go Test", which is typically adopted for gait analysis in rehabilitation fields. Starting from the depth-data stream provided by the Microsoft Kinect sensor, the proposed algorithm relies on anthropometric models only, to locate and identify the positions of the joints. Differently from machine learning approaches, this solution avoids complex computations, which usually require significant resources. The reliability of the information about the joint position output by the algorithm is evaluated by comparison to a marker-based system. Tests show that the trajectories extracted by the proposed algorithm adhere to the reference curves better than the ones obtained from the skeleton generated by the native applications provided within the Microsoft Kinect (Microsoft Corporation, Redmond,WA, USA, 2013) and OpenNI (OpenNI organization, Tel Aviv, Israel, 2013) Software Development Kits.
Enea Cippitelli
2015-01-01
Full Text Available The Microsoft Kinect sensor has gained attention as a tool for gait analysis for several years. Despite the many advantages the sensor provides, however, the lack of a native capability to extract joints from the side view of a human body still limits the adoption of the device to a number of relevant applications. This paper presents an algorithm to locate and estimate the trajectories of up to six joints extracted from the side depth view of a human body captured by the Kinect device. The algorithm is then applied to extract data that can be exploited to provide an objective score for the “Get Up and Go Test”, which is typically adopted for gait analysis in rehabilitation fields. Starting from the depth-data stream provided by the Microsoft Kinect sensor, the proposed algorithm relies on anthropometric models only, to locate and identify the positions of the joints. Differently from machine learning approaches, this solution avoids complex computations, which usually require significant resources. The reliability of the information about the joint position output by the algorithm is evaluated by comparison to a marker-based system. Tests show that the trajectories extracted by the proposed algorithm adhere to the reference curves better than the ones obtained from the skeleton generated by the native applications provided within the Microsoft Kinect (Microsoft Corporation, Redmond,WA, USA, 2013 and OpenNI (OpenNI organization, Tel Aviv, Israel, 2013 Software Development Kits.
Zemcov, Michael; Crill, Brendan; Ryan, Matthew; Staniszewski, Zak
2016-06-01
Mega-pixel charge-integrating detectors are common in near-IR imaging applications. Optimal signal-to-noise ratio estimates of the photocurrents, which are particularly important in the low-signal regime, are produced by fitting linear models to sequential reads of the charge on the detector. Algorithms that solve this problem have a long history, but can be computationally intensive. Furthermore, the cosmic ray background is appreciable for these detectors in Earth orbit, particularly above the Earth’s magnetic poles and the South Atlantic Anomaly, and on-board reduction routines must be capable of flagging affected pixels. In this paper, we present an algorithm that generates optimal photocurrent estimates and flags random transient charge generation from cosmic rays, and is specifically designed to fit on a computationally restricted platform. We take as a case study the Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx), a NASA Small Explorer astrophysics experiment concept, and show that the algorithm can easily fit in the resource-constrained environment of such a restricted platform. Detailed simulations of the input astrophysical signals and detector array performance are used to characterize the fitting routines in the presence of complex noise properties and charge transients. We use both Hubble Space Telescope Wide Field Camera-3 and Wide-field Infrared Survey Explorer to develop an empirical understanding of the susceptibility of near-IR detectors in low earth orbit and build a model for realistic cosmic ray energy spectra and rates. We show that our algorithm generates an unbiased estimate of the true photocurrent that is identical to that from a standard line fitting package, and characterize the rate, energy, and timing of both detected and undetected transient events. This algorithm has significant potential for imaging with charge-integrating detectors in astrophysics, earth science, and remote
UML statechart based rigorous modeling of real-time system
LAI Ming-zhi; YOU Jin-yuan
2005-01-01
Rigorous modeling could ensure correctness and could verify a reduced cost in embedded real-time system development for models. Software methods are needed for rigorous modeling of embedded real-time systems. PVS is a formal method with precise syntax and semantics defined. System modeled by PVS specification could be verified by tools. Combining the widely used UML with PVS, this paper provides a novel modeling and verification approach for embedded real-time systems. In this approach, we provide 1 ) a time-extended UML statechart for modeling dynamic behavior of an embedded real-time system; 2) an approach to capture timed automata based semantics from a timed statechart; and 3) an algorithm to generate a finite state model expressed in PVS specification for model checking. The benefits of our approach include flexibility and user friendliness in modeling, extendability in formalization and verification content, and better performance. Time constraints are modeled and verified and is a highlight of this paper.
Anghel, Adela; Carrano, Charles; Komjathy, Attila; Astilean, Adina; Letia, Tiberiu
2009-01-01
Data collected from a GPS receiver located at low latitudes in the American sector are used to investigate the performance of the WinTEC algorithm [Anghel et al., 2008a, Kalman filter-based algorithm for near realtime monitoring of the ionosphere using dual frequency GPS data. GPS Solutions, accepted for publication; for different ionospheric modeling techniques: the single-shell linear, quadratic, and cubic approaches, and the multi-shell linear approach. Our results indicate that the quadratic and cubic approaches perform much better than the single-shell and multi-shell linear approaches in terms of post-fit residuals. The performance of the algorithm for the cubic approach is then further tested by comparing the vertical TEC predicted by WinTEC and USTEC [Spencer et al., 2004. Ionospheric data assimilation methods for geodetic applications. In: Proceedings of IEEE PLANS, Monterey, CA, 26-29 April, pp. 510-517] at five North American stations. In addition, since the GPS-derived total electron content (TEC) contains contributions from both ionospheric and plasmaspheric sections of the GPS ray paths, in an effort to improve the accuracy of the TEC retrievals, a new data assimilation module that uses background information from an empirical plasmaspheric model [Gallagher et al., 1988. An empirical model of the Earth's plasmasphere. Advances in Space Research 8, (8)15-(8)24] has been incorporated into the WinTEC algorithm. The new Kalman filter-based algorithm estimates both the ionospheric and plasmaspheric electron contents, the combined satellite and receiver biases, and the estimation error covariance matrix, in a single-site or network solution. To evaluate the effect of the plasmaspheric component on the estimated biases and total TEC and to assess the performance of the newly developed algorithm, we compare the WinTEC results, with and without the plasmaspheric term included, at three GPS receivers located at different latitudes in the American sector, during
Simulating and Visualizing Real-Time Crowds on GPU Clusters
Benjamín Hernández; Hugo Pérez; Isaac Rudomin; Sergio Ruiz; Oriam de Gyves; Leonel Toledo
2014-01-01
We present a set of algorithms for simulating and visualizing real-time crowds in GPU (Graphics Processing Units) clusters. First we present crowd simulation and rendering techniques that take advantage of single GPU machines. Then, using as an example a wandering crowd behavior simulation algorithm, we explain how this kind of algorithms can be extended for their use in GPU cluster environments. We also present a visualization architecture that renders the simulation results using detailed 3...
Zemcov, Michael; Ryan, Matthew; Staniszewski, Zak
2016-01-01
Mega-pixel charge-integrating detectors are common in near-IR imaging applications. Optimal signal-to-noise ratio estimates of the photocurrents, which are particularly important in the low-signal regime, are produced by fitting linear models to sequential reads of the charge on the detector. Algorithms that solve this problem have a long history, but can be computationally intensive. Furthermore, the cosmic ray background is appreciable for these detectors in Earth orbit, particularly above the Earth's magnetic poles and the South Atlantic Anomaly, and on-board reduction routines must be capable of flagging affected pixels. In this paper we present an algorithm that generates optimal photocurrent estimates and flags random transient charge generation from cosmic rays, and is specifically designed to fit on a computationally restricted platform. We take as a case study the Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx), a NASA Small Explorer astrophysics...
Stuart-Smith, J.; Rathcke, T.; Sonderegger, M.; Macdonald, R.
2015-01-01
This paper presents a collaborative study of variation and potential change in the voicing contrast in Scottish English plosives, analyzed in recordings from twelve vernacular female speakers of different generations made in the 1970s and the 2000s in Glasgow. We adapted an existing automatic measurement algorithm for predicting Voice Onset Time (VOT) originally developed for voiceless stops, for the analysis of voiced and voiceless plosives in casual sociolinguistic speech recordings of diff...
Karimipour, Atiyeh; Homaeinezhad, Mohammad Reza
2014-09-01
The main objective of this study is to introduce a simple, low-latency, and accurate algorithm for real-time detection of P-QRS-T waves in the electrocardiogram (ECG) signal. In the proposed method, real-time signal preprocessing, which includes high frequency noise filtering and baseline wander reduction, is performed by applying discrete wavelet transform (DWT). A method based on signal first-order derivative and adaptive threshold adjustment is employed for real-time detection of the QRS complex. Moreover, detection and delineation of P- and T-waves are achieved by correlation analysis conducted between signal and their templates. Besides, signal quality is investigated online, and if the quality of the analysis window is unacceptable, then the algorithm will guess (estimate) the locations of P- and T-waves. The operating characteristics of the proposed algorithm are evaluated by its implementation to an artificially generated ECG signal whose quality is adjustable from the best (Quality, 100%) to the worst (Quality, ≤40%) cases based on the random-walk noise theory. The algorithm was applied to the MIT-BIH arrhythmia database, QT database, and Physionet/CinC challenge 2011competition database. The obtained results, which were based on the QT database, showed sensitivity and positive predictivity of Se=99.63% and P+=99.83%, Se=99.83% and P+=99.98%, and Se=99.74% and P+=99.89% for the detection of P-, QRS-, and T-waves, respectively, and the obtained results, which were based on the MIT-BIH arrhythmia database, showed Se=99.81% and P+=99.70% for the detection of the QRS complex. Moreover, it will be shown that the results of the proposed method are reliable for a minimum signal quality value of 70%. According to numerical assessments, 8-ms after the occurrence of R-wave, its location will be identified by the computer code of the proposed algorithm. This parameter is 198-ms and 177-ms for P- and T-waves, respectively.
计算平面点集凸包的实时插入算法%Real-time Insert Algorithm for Computing Convex Hull of Finite Planar Sets
刘萍
2013-01-01
讨论平面点集的凸包实时插入算法.算法基于Graham扫描算法,对3个点检测顺序的转向.本文证明,当S的N个点以流的形式进入系统,计算S的凸包所需的检测次数小于3N.%In this paper, based on Graham scan algorithm, a real-time algorithm for computing convex hull of a finite planar set is proposed to check the sequential turn of 3 points. If N points of S are to be computed as stream, the number of tests for computing convex hull of S is lower than 3N.
基于用户实时反馈的协同过滤算法%Collaborative filtering algorithm based on real-time user feedback
傅鹤岗; 李冉
2011-01-01
Traditional memory-based collaborative filtering algorithm has the problem of bad scalability, while the modelbased collaborative filtering algorithm, due to lagged updating hysterics, has the problem of bad recommendation. To solve the above problems, a collaborative filtering algorithm based on real-time users' feedback was proposed, which achieved that recommender system can finish the real-time updating of the model data when a new rating was submitted by active user.Hence, recommender system can reflect the changing of user interest accurately. The experimental results indicate that the algorithm can improve the recommendation accuracy efficiently and reduce the recommendation time significantly.%传统的基于内存的协同过滤算法存在可扩展性不足的问题,而基于模型的协同过滤算法由于模型数据的滞后,造成推荐质量不高.针对以上情况,提出一种基于用户实时反馈的协同过滤算法,该算法在用户提交项目评分之后能实现对推荐模型数据的实时更新,从而更精确地反映用户的兴趣变化.实验结果表明,该算法能够有效地提高推荐精确度并且大幅地缩短了推荐时间.
A Causal and Real-Time Capable Power Management Algorithm for Off-Highway Hybrid Propulsion Systems
Johannes Schalk
2016-12-01
Full Text Available Hybrid propulsion systems allow for a reduction of fuel consumption and pollutant emissions of future off-highway applications. A challenging aspect of a hybridization is the larger number of system components that further increases both the complexity and the diversification of such systems. Hence, beside a standardization on the hardware side for off-highway systems, a high flexibility and modularity of the control schemes is required to employ them in as many different applications as possible. In this paper, a causal optimization-based power management algorithm is introduced to control the power split between engine and electric machine in a hybrid powertrain. The algorithm optimizes the power split to achieve the maximum power supply efficiency and, thereby, considers the energy cost for maintaining the battery charge. Furthermore, the power management provides an optional function to control the battery state of charge in such a way that a target value is attained. In a simulation case study, the potential and the benefits of the proposed power management for the hybrid powertrain—aiming at a reduction of the fuel consumption of a DMU (diesel multiple unit train operated on a representative track—will be shown.
Behera, H S; Panda, Bijayalakshmi; 10.5120/2037-2648
2011-01-01
The main objective of the paper is to improve the Round Robin (RR) algorithm using dynamic ITS by coalescing it with Shortest Remaining Time Next (SRTN) algorithm thus reducing the average waiting time, average turnaround time and the number of context switches. The original time slice has been calculated for each process based on its burst time.This is mostly suited for soft real time systems where meeting of deadlines is desirable to increase its performance. The advantage is that processes that are closer to their remaining completion time will get more chances to execute and leave the ready queue. This will reduce the number of processes in the ready queue by knocking out short jobs relatively faster in a hope to reduce the average waiting time, turn around time and number of context switches. This paper improves the algorithm [8] and the experimental analysis shows that the proposed algorithm performs better than algorithm [6] and [8] when the processes are having an increasing order, decreasing order an...
前景/背景分割算法及其嵌入式实时实现%Real-time embedded implementation of foreground/background segmentation algorithm
张浩钧; 常勇; 李范鸣; 沈永格
2012-01-01
前景/背景分割算法是计算机视觉中一种常见的算法.其基本思想是利用背景中不同像素或帧与帧之间的相关性,判断每个像素点的灰度值,然后根据预测值和实际观察值判断当前像素属于前景还是背景.首先介绍了几种应用在不同场合的前景/背景分割算法.考虑到应用传统的基于处理器的平台很难实时实现这类计算量很大的算法,所以在该算法的有效性被确认后,重点介绍其嵌入式实时实现.同时引入了一种先进的实现算法的方法:可重构计算及其设计方法和流程.另外还讨论了几个重要的关于硬件实现算法的问题.在给出了如何应用可重构计算实现算法的实例后,介绍了如何把已实现的算法嵌入基于片上系统的成像系统,以实现一个完整的系统.%Foreground/Background (FG/BG) segmentation is one of the most widely-used computer vision (CV) algorithms. Its basic algorithm takes advantages of correlation between background of different pixels or frames, predicts gray intensity for every pixel point and judges whether it belongs to foreground or background based on the prediction and actual value. Several FG/BG algorithms used in different situation were introduced firstly. Considering that those tomputationally expensive algorithms are hard to operate in real time using the traditional processor-based platform, its real-time embedded implementation was highlighted after this algorithm being verified. The design methodology and flow of reconfigurable computing (RC) which was an advanced method to implement those algorithms were introduced. In addition, several important issues about hardware implementation were discussed. A case of study to elaborate how it works was presented, and how to attach the implemented algorithm into the SoPC-based imaging system to achieve an integrated system was described.
An Improved Shadow Maps Algorithm for Real-time Rendering%基于Shadow Maps的实时阴影生成算法改进
张伟; 奚俊峰
2011-01-01
To build vivider shadows for real-time rendering in three-dimensional animation, Shadow Maps algorithm is studied and improved. By taking main value of average segmentation and logarithmic segmentation as the parameter to divide the shadow scene, the perspective aliasing is relieved. And by building and buffing the shadow maps twice with proper offset, the shadow acne, which caused by self-shadow error, is cleared up. The improved algorithm is implemented based on OpenGL with common graphic hardware and Windows XP. It's shown that the algorithm can build high quality shadows with satisfying the demand of the real-time rendering.%为了在三维动画场景中实时生成更逼真的阴影,分析了Shadow Maps 阴影生成算法走样和失真问题的原因.采用平均分割与对数分割相结合的方法改进了透视走样同题,采用双阴影图法改进了自阴影绘制问题.在Windows XP环境中,基于OpenGL库,编程实现了Shadow Maps算法改进.实验表明,在目前流行的硬件配置环境下,改进后的算法在阴影生成过程中能满足实时渲染帧率要求,同时增强虚拟场景阴影质量.
SUYajuan; WEIShaojun
2005-01-01
Technique of energy minimization by combining Dynamic voltage scheduling (DVS) and Adaptive body biasing voltage (ABB) method for distributed realtime system at design level is proposed. First, a simplified energy optimizing model is illustrated where the supply voltage or body biasing voltage is kept as constant according to each separated frequency region, thus calculation of exceeding equation is avoided. Divergence of simplified and analytic model within 5% indicates the accuracy of this model. Based on it, the proposed approach named LEVVS (Low energy supply voltage and body biasing voltage scheduling algorithm) explores space of minimizing energy consumption by finding optimal trade-off between dynamic and static energy. The corresponding optimal supply voltage and body biasing voltage are determined by an iterative method in which the supply voltage and body biasing voltage of tasks are adjusted according to the value of energy latency differential coefficient of each task and slack time distribution of the system. Experiments show that using LEVVS approach, 51% more average energy reduction can be obtained than employing DVS method alone. Furthermore the effects of switch capacitance and global slack on the energy saving efficiency of LEVVS are investigated. The smaller the global slack or average switch capacitance is, the more the energy saving of LEVVS compared with DVS is.
Indoor Localization of a Quadrotor Based on WSN: A Real-Time Application
Jose L. Rullan-Lara
2013-01-01
Full Text Available A real-time localization algorithm is presented in this paper. The algorithm presented here uses an extended Kalman filter and is based on Time Difference Of Arrivals (TDOA measurements of radio signal. The position and velocity of an Unmanned Aerial Vehicle (UAV are successfully estimated in closed-loop in real-time, both in hover and path following flights. Relatively small position errors obtained from the experiments prove the good performance of the proposed algorithm.
Auer, Tibor; Schweizer, Renate; Frahm, Jens
2015-01-01
This study investigated the level of self-regulation of the somatomotor cortices (SMCs) attained by an extended functional magnetic resonance imaging (fMRI) neurofeedback training. Sixteen healthy subjects performed 12 real-time functional magnetic resonance imaging neurofeedback training sessions within 4 weeks, involving motor imagery of the dominant right as well as the non-dominant left hand. Target regions of interests in the SMC were individually localized prior to the training by overt finger movements. The feedback signal (FS) was defined as the difference between fMRI activation in the contra- and ipsilateral SMC and visually presented to the subjects. Training efficiency was determined by an off-line general linear model analysis determining the fMRI percent signal changes in the SMC target areas accomplished during the neurofeedback training. Transfer success was assessed by comparing the pre- and post-training transfer task, i.e., the neurofeedback paradigm without the presentation of the FS. Group results show a distinct increase in feedback performance (FP) in the transfer task for the trained group compared to a matched untrained control group, as well as an increase in the time course of the training, indicating an efficient training and a successful transfer. Individual analysis revealed that the training efficiency was not only highly correlated to the transfer success but also predictive. Trainings with at least 12 efficient training runs were associated with a successful transfer outcome. A group analysis of the hemispheric contributions to the FP showed that it is mainly driven by increased fMRI activation in the contralateral SMC, although some individuals relied on ipsilateral deactivation. Training and transfer results showed no difference between left- and right-hand imagery, with a slight indication of more ipsilateral deactivation in the early right-hand trainings.
Tibor eAuer
2015-10-01
Full Text Available This study investigated the level of self-regulation of the somato-motor cortices (SMC attained by an extended functional MRI (fMRI neurofeedback training. Sixteen healthy subjects performed 12 real-time functional magnetic resonance imaging (rt-fMRI neurofeedback training sessions within 4 weeks, involving motor imagery of the dominant right as well as the non-dominant left hand. Target regions of interests in the SMC were individually localized prior to the training by overt finger movements. The feedback signal was defined as the difference between fMRI activation in the contra- and ipsilateral SMC and visually presented to the subjects. Training efficiency was determined by an off-line GLM analysis determining the fMRI percent signal changes in the somato-motor cortex (SMC target areas accomplished during the neurofeedback training. Transfer success was assessed by comparing the pre- and post-training transfer task, i.e. the neurofeedback paradigm without the presentation of the feedback signal. Group results show a distinct increase in feedback performance in the transfer task for the trained group compared to a matched untrained control group, as well as an increase in the time course of the training, indicating an efficient training and a successful transfer. Individual analysis revealed that the training efficiency was not only highly correlated to the transfer success but also predictive. Trainings with at least 12 efficient training runs were associated with a successful transfer outcome. A group analysis of the hemispheric contributions to the feedback performance showed that it is mainly driven by increased fMRI activation in the contralateral SMC, although some individuals relied on ipsilateral deactivation. Training and transfer results showed no difference between left and right hand imagery, with a slight indication of more ipsilateral deactivation in the early right hand trainings.
Two Improved EDF Dynamic Scheduling Algorithms in Soft Real-Time Systems%两种改进的EDF软实时动态调度算法
李琦; 巴巍
2011-01-01
软实时系统中,任务的随意抢占浪费了CPU资源,过多的任务丢失降低了系统的调度性能.文章引入"动态模糊阈值"概念,提出了两种新的类似EDF调度的模糊阈值调度算法.两种算法在任务执行过程中,分别通过缩短和延长当前任务截止期至动态模糊阈值的方法节约资源、提高任务完成率.给出模糊阈值的临界值计算公式,分析算法的可调度性,进行仿真与性能分析比较.结果表明,与EDF调度算法比较,两种算法有效地提高了重要任务的完成率,当截止期被延长时,任务的错失率明显降低,当截止期被缩短时,任务间的切换次数大大减少.因此,新算法提高了CPU的利用率,改善了系统的实时性能.%In soft real-time systems, the CPU resource is wasted by switching optionally and the schedulability of the system is decreased by the losing of overmany tasks.The concept of dynamic fuzzy threshold is introduced in this paper, based on which two improved EDF scheduling algorithms are proposed.The deadline of the executing task is delayed to save the resource in one algorithm and is shorten to increase the ratio of success in the other.In this paper, the formulae of the critical value for fuzzy threshold are given and the schedulability is discussed.Finally, the performance of the algorithms is experimentally examined and compared with the EDF algorithm in detail.Results show that, the ratio of success for important tasks is increased efficiently by using these two methods.The missed deadline percentage is decreased obviously while the deadline is delayed and the switching number is reduced greatly while the deadline is shorten.Therefore, by using the new algorithms, the ratio of CPU utilization is enhanced and the real-time capability of the system is improved.
Development of Fast Real-time NURBS Direct Interpolation Algorithm%实时快速NURBS直接插补技术
王国勋; 王宛山; 王军; 舒启林
2013-01-01
To solve the problem of speed fluctuation existing in NURBS interpolation algorithm under Taylor expansion and enhance interpolation in real-time, a method on NURBS curve interpolation was studied. A new interpolation method on the principle of interpolation and an algorithm of fast evaluation and derivation were proposed. Under the precondition to satisfy the accuracy demands in interpolation process, the method utilized calculation of the next point coordinates directly using fee-drate, and using the recursive matrix to fast calculate the NURBS' value and derivative, decreases effectively the issue of speed fluctuation, and enhances the calculation speed and interpolation in real- time. Simulation experiments indicate that the proposed method is effective and feasible.%为了解决基于泰勒展开式的NURBS插补算法存在的速度波动问题,提高NURBS插补实时性,深入研究了NURBS曲线直接插补方法.根据插补原理,提出了一种不同于泰勒展开式的插补计算方法,并研究了一种NURBS快速计算方法.在满足插补过程精度要求的前提下,由进给速度直接计算插补点坐标,并采用递推矩阵对NURBS进行快速求值求导计算,有效地减小了速度波动,而且提高了计算速度和插补实时性.仿真结果证明了该方法的可行性和有效性.
Christensen, Knud Smed
2000-01-01
Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....
Christensen, Knud Smed
2000-01-01
Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems.......Describes fundamentals of parallel programming and a kernel for that. Describes methods for modelling and checking parallel problems. Real time problems....
L. Bressan
2011-05-01
Full Text Available The goal of this paper is to present an original real-time algorithm devised for detection of tsunami or tsunami-like waves we call TEDA (Tsunami Early Detection Algorithm, and to introduce a methodology to evaluate its performance. TEDA works on the sea level records of a single station and implements two distinct modules running concurrently: one to assess the presence of tsunami waves ("tsunami detection" and the other to identify high-amplitude long waves ("secure detection". Both detection methods are based on continuously updated time functions depending on a number of parameters that can be varied according to the application. In order to select the most adequate parameter setting for a given station, a methodology to evaluate TEDA performance has been devised, that is based on a number of indicators and that is simple to use. In this paper an example of TEDA application is given by using data from a tide gauge located at the Adak Island in Alaska, USA, that resulted in being quite suitable since it recorded several tsunamis in the last years using the sampling rate of 1 min.
Kim, Hie-Sik; Nam, Chul; Ha, Kwan-Yong; Ayurzana, Odgeral; Kwon, Jong-Won
2005-12-01
The embedded systems have been applied to many fields, including households and industrial sites. The user interface technology with simple display on the screen was implemented more and more. The user demands are increasing and the system has more various applicable fields due to a high penetration rate of the Internet. Therefore, the demand for embedded system is tend to rise. An embedded system for image tracking was implemented. This system is used a fixed IP for the reliable server operation on TCP/IP networks. Using an USB camera on the embedded Linux system developed a real time broadcasting of video image on the Internet. The digital camera is connected at the USB host port of the embedded board. All input images from the video camera are continuously stored as a compressed JPEG file in a directory at the Linux web-server. And each frame image data from web camera is compared for measurement of displacement Vector. That used Block matching algorithm and edge detection algorithm for past speed. And the displacement vector is used at pan/tilt motor control through RS232 serial cable. The embedded board utilized the S3C2410 MPU, which used the ARM 920T core form Samsung. The operating system was ported to embedded Linux kernel and mounted of root file system. And the stored images are sent to the client PC through the web browser. It used the network function of Linux and it developed a program with protocol of the TCP/IP.
Eisemann, Elmar; Assarsson, Ulf; Wimmer, Michael
2011-01-01
Important elements of games, movies, and other computer-generated content, shadows are crucial for enhancing realism and providing important visual cues. In recent years, there have been notable improvements in visual quality and speed, making high-quality realistic real-time shadows a reachable goal. Real-Time Shadows is a comprehensive guide to the theory and practice of real-time shadow techniques. It covers a large variety of different effects, including hard, soft, volumetric, and semi-transparent shadows.The book explains the basics as well as many advanced aspects related to the domain
Real-Time Attitude Independent Three Axis Magnetometer Calibration
Crassidis, John L.; Lai, Kok-Lam; Harman, Richard R.
2003-01-01
In this paper new real-time approaches for three-axis magnetometer sensor calibration are derived. These approaches rely on a conversion of the magnetometer-body and geomagnetic-reference vectors into an attitude independent observation by using scalar checking. The goal of the full calibration problem involves the determination of the magnetometer bias vector, scale factors and non-orthogonality corrections. Although the actual solution to this full calibration problem involves the minimization of a quartic loss function, the problem can be converted into a quadratic loss function by a centering approximation. This leads to a simple batch linear least squares solution. In this paper we develop alternative real-time algorithms based on both the extended Kalman filter and Unscented filter. With these real-time algorithms, a full magnetometer calibration can now be performed on-orbit during typical spacecraft mission-mode operations. Simulation results indicate that both algorithms provide accurate integer resolution in real time, but the Unscented filter is more robust to large initial condition errors than the extended Kalman filter. The algorithms are also tested using actual data from the Transition Region and Coronal Explorer (TRACE).
A graphics processing unit (GPU)-based real-time spherizing algorithm%基于GPU的实时球面化算法
黄建彪; 陈国华; 张爱军; 周厉颖
2013-01-01
分析了球面映射算法速度过慢的原因,针对传统插值计算中普遍存在的速度与精度相互制约的问题,改进了现有的基于立体投影的半球面纹理映射模型,提出了基于GPU的球面化算法,使用CUDA并行编程实现双线性插值的并行计算.球面化实验表明该算法在保证输出精度的前提下,可获得10倍左右的加速比,显著提高了计算速度,可用于实时性较高的应用场合.%The cause of the low speed of a sphere mapping algorithm has been analyzed. In order to reduce the interaction between speed and accuracy, which is common in traditional interpolation methods with existing sphere mapping algorithms, an improved hemisphere texture mapping model based on stereoscopic projection has been proposed , and a graphics processing unit ( GPU ) -based spherizing algorithm has been put forward, in which CUDA parallel programming was utilized to complete the parallel computing of bilinear interpolation. The experiments showed that the computing speed could be significantly increased with the new method, whilst ensuring output accuracy. The method gave a speedup factor of almost 10, and it could be employed in fast real-time applications.
Gambacorta, A.; Barnet, C. D.; Smith, N.; Pierce, R. B.; Smith, J. W.; Spackman, J. R.; Goldberg, M.
2016-12-01
NUCAPS is the NOAA operational algorithm to retrieve thermodynamic variables from hyper spectral thermal sounders such as CrIS on NPP and J1, IASI on MetOp and AIRS on Aqua, in conjunction with microwave sounders, such as ATMS, AMSU and MHS. NUCAPS builds on a long-term, multi-agency investment on algorithm research and development. The uniqueness of this algorithm consists in a number of features that are key in providing highly accurate and stable atmospheric retrievals, suitable for both real time weather and long-term climate applications. NUCAPS is an all-weather, full column and high vertical resolution system compatible with multiple hyper spectral sounders. This design was intended to enable multiple, global yet consistent daily measurements of the full atmospheric state and plays a critical role in filling in for the NWS in-situ measurement gaps, particularly during the early afternoon pre-convective and fast developing regimes. We are now developing the capability to run a Lagrangian transport model that can collocate NUCAPS thermodynamic fields to surface wind fields and propagate NUCAPS moist and dry layers in time and space. This is key to enhance a forecaster's predictive knowledge of what sources are at play in the evolution or suppression of convective or fire events. NUCAPS has proven robust in capturing extreme and high impact weather events during previously held JPSS PGRR initiatives, such as the 2015 CalWater, the 2016 Hazardous Test bed Spring Experiment, SENEX, SONGNEX and the 2016 El Nino Rapid Response campaign. Results from these initiatives will be presented at the meeting.
Kalman Filtering with Real-Time Applications
Chui, Charles K
2009-01-01
Kalman Filtering with Real-Time Applications presents a thorough discussion of the mathematical theory and computational schemes of Kalman filtering. The filtering algorithms are derived via different approaches, including a direct method consisting of a series of elementary steps, and an indirect method based on innovation projection. Other topics include Kalman filtering for systems with correlated noise or colored noise, limiting Kalman filtering for time-invariant systems, extended Kalman filtering for nonlinear systems, interval Kalman filtering for uncertain systems, and wavelet Kalman filtering for multiresolution analysis of random signals. Most filtering algorithms are illustrated by using simplified radar tracking examples. The style of the book is informal, and the mathematics is elementary but rigorous. The text is self-contained, suitable for self-study, and accessible to all readers with a minimum knowledge of linear algebra, probability theory, and system engineering.
一种深度图像中人体的实时跟踪算法%A Human Body Real-time Tracking Algorithm in Depth Image
曹昊; 诸宸辰; 李杨
2013-01-01
This paper proposes an improving Camshift algorithm based on depth data in order to realize real-time human body objects tracking in depth image. This algorithm computes depth probability distribution function of human body objects, combining the morphological characteristics of people. Different weight factors are given to the different part of human on depth probability distribution function. It finds human body objects in a frame after several times of iterations, uses the modified Camshift algorithm. Kalman filter is also applied in this work to predict the position of people in 3D space. Doing experiments on 1 200 frames of depth image, results present that this algorithm are effective to track moving human body on depth image even though the objects are partly covered or the shapes are regular changed. For the common one or two people situation, the tracking accuracy rate is over 95%, which is better than traditional Camshift algorithm.%针对深度图像中的人体目标跟踪问题，提出一种基于深度图像的改进Camshift算法。利用人体目标的深度信息计算概率分布，结合人体形态学特征，对深度的概率分布赋予不同的权重，通过Camshift算法进行迭代，从而寻找目标，使用卡尔曼滤波器在三维空间中对运动人体目标的位置实现预测和更新。采集1200帧图像进行测试，结果表明，该算法能实时准确地跟踪深度图像中的运动人体目标，有效克服遮挡等干扰，单人和双人跟踪准确率均在95%以上，高于传统Camshift算法。
Yuyan Tan
2015-01-01
Full Text Available With the aim of supporting the process of adapting railway infrastructure and future traffic needs, we have developed a method to insert additional trains efficiently to an existing timetable without introducing large consecutive delays to scheduled trains. In this work, the problem is characterized as a job-shop scheduling problem. In order to meet the limited time requirement and minimize deviations to the existing timetable, the modification that consists of retiming or reordering trains is implemented if and only if it potentially leads to a better solution. With these issues in mind, the problem of adding train paths is decomposed into two subproblems. One is finding the optimal insertion for a fixed order timetable and the other is reordering trains. The two subproblems are solved iteratively until no improvement is possible within a time limit of computation. An innovative branch and bound algorithm and iterative reordering strategy are proposed to solve this problem in real time. Unoccupied capacities are utilized as primary resources for additional trains and the transfer connections for passengers can be guaranteed in the new timetable. From numerical investigations, the proposed framework and associated techniques are tested and shown to be effective.
New Scheduling Algorithm for Mixed-Criticality Real-Time Task Sets%新的混合关键任务调度算法的研究
朱怡安; 黄姝娟; 段俊花; 陆伟
2014-01-01
By analyzing the problems of real-time scheduling in mix-criticality systems, a new scheduling algorithm, forward and backward time window partition-criticality factor prior (FBTWP-CFP), is proposed. It can separate the running time windows for the tasks of all criticality levels offline from the forward direction and backward direction and generate the idle windows for the tasks which get the lower priority by the criticality factor for the criticality level changed. The simulation results show that FBTWP-CFP is better than criticality assigned priority algorithm (CAPA) and own criticality based priority (OCBP) in completed tasks number and reduced miss deadline ratio.%分析了混合关键系统中当前任务调度方法存在的问题，提出一种正反向时间分割和关键因子优先的调度算法，该方法将所有混合关键任务按照不同级别进行时间正反向分割得出空闲时间窗口，并根据关键因子的大小决定优先级别。为了减少在关键级别转化过程中优先级低的任务丢失死限的工作数量，将空闲窗口分配给由于关键级别转化而使得优先级落后的任务。仿真实验表明，该方法在降低任务丢失死限率和完成任务的数量方面比按照关键级别进行优先级指派算法(CAPA)和OCBP方法较优。
Bossi, R.H.; Oien, C.T.
1981-02-26
Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.
Quercellini, Claudia; Balbi, Amedeo; Cabella, Paolo; Quartin, Miguel
2010-01-01
In recent years the possibility of measuring the temporal change of radial and transverse position of sources in the sky in real time have become conceivable thanks to the thoroughly improved technique applied to new astrometric and spectroscopic experiments, leading to the research domain we call Real-time cosmology. We review for the first time great part of the work done in this field, analysing both the theoretical framework and some endeavor to foresee the observational strategies and their capability to constrain models. We firstly focus on real time measurements of the overall redshift drift and angular separation shift in distant source, able to trace background cosmic expansion and large scale anisotropy, respectively. We then examine the possibility of employing the same kind of observations to probe peculiar and proper acceleration in clustered systems and therefore the gravitational potential. The last two sections are devoted to the short time future change of the cosmic microwave background, as ...
Olano, Marc
2002-01-01
This book covers real-time shading systems, their design and how they work. Procedural shading, long valued for off-line rendering and production animation is now possible on interactive graphics hardware. These developments are important for areas such as game development, product design, and scientific visualization, among others. The authors include examples of techniques for achieving common effects efficiently in a real-time shading language ranging from full procedural shading on advanced specialized hardware to limited, yet surprisingly flexible shading on unextended OpenGL, to modern P
Research in Distributed Real-Time Systems
Mukkamala, R.
1997-01-01
This document summarizes the progress we have made on our study of issues concerning the schedulability of real-time systems. Our study has produced several results in the scalability issues of distributed real-time systems. In particular, we have used our techniques to resolve schedulability issues in distributed systems with end-to-end requirements. During the next year (1997-98), we propose to extend the current work to address the modeling and workload characterization issues in distributed real-time systems. In particular, we propose to investigate the effect of different workload models and component models on the design and the subsequent performance of distributed real-time systems.
Gilberto Ochoa-Ruiz
2017-01-01
Full Text Available We present an architecture for accelerating the processing and execution of control commands in an ultrafast fiber placement robot. The system consists of a robotic arm designed by Coriolis Composites whose purpose is to move along a surface, on which composite fibers are deposed, via an independently controlled head. In first system implementation, the control commands were sent via Profibus by a PLC, limiting the reaction time and thus the precision of the fiber placement and the maximum throughput. Therefore, a custom real-time solution was imperative in order to ameliorate the performance and to meet the stringent requirements of the target industry (avionics, aeronautical systems. The solution presented in this paper is based on the use of a SoC FPGA processing platform running a real-time operating system (FreeRTOS, which has enabled an improved comamnd retrieval mechanism. The system’s placement precision was improved by a factor of 20 (from 1 mm to 0.05 mm, while the maximum achievable throughput was 1 m/s, compared to the average 30 cm/s provided by the original solution, enabling fabricating more complex and larger pieces in a significant fraction of the time.
Real-time Task Scheduling Algorithm Based on Grid Platform%基于网格平台的实时任务调度算法
南洋; 阎巍; 齐景嘉
2012-01-01
The goal of grid task scheduling is to achieve global optimization scheduling scheme by allocating tasks in the shortest time with load balancing. In this paper, we propose a real-time,grid task scheduling algorithm considering task dependency and load balancing. Firstly, grid is divided into several clusters, and each cluster consists of PC, task scheduling module, task controller, data set of controller and data memory. Cluster is responsible for receiving tasks submitted by users, and these tasks are stored in the local task queue. After analyzing task dependency, tasks are assigned to cluster of grid according to task priority, which is computed by combining task deadline and task dependency. Simulation results show that in the aspect of Makespan and cost, the proposed algorithm is superior to the traditional Min-Min algorithm.%网格任务调度的目标是在最短的时间内将任务进行合理分配并实现负载均衡,最终得到实现全局的最优化调度方案.本文提出了一种兼顾任务之间的依赖关系和负载均衡的网格任务实时调度算法.首先,将网格分成若干个簇,每个簇由PC机、任务调度模块、任务控制器、数据集控制器以及数据存储器组成.簇负责接收用户提交的任务,将这些任务存放在本地任务队列中.通过对任务依赖关系的分析,将任务分配给网格的簇,并根据任务的截止期和依赖关系计算任务优先级,优先调度优先级高的任务.仿真实验表明,在Makespan和花费方面,本文算法都优于传统的Min-Min算法.
UNHCR
2002-07-01
Full Text Available A real-time evaluation (RTE is a timely, rapid andinteractive review of a fast evolving humanitarianoperation undertaken at an early phase. Its broadobjectives are to gauge the effectiveness and impactof a given UNHCR response and to ensure that itsfindings are used as an immediate catalyst fororganisational and operational change.
Practical constraints on real time Bayesian filtering for NDE applications
Summan, R.; Pierce, S.; Dobie, G.; Hensman, J.; MacLeod, C.
2014-01-01
An experimental evaluation of Bayesian positional filtering algorithms applied to mobile robots for Non-Destructive Evaluation is presented using multiple positional sensing data - a real time, on-robot implementation of an Extended Kalman and Particle filter was used to control a robot performing representative raster scanning of a sample. Both absolute and relative positioning were employed - the absolute being an indoor acoustic GPS system that required careful calibration. The performance of the tracking algorithms are compared in terms of computational cost and the accuracy of trajectory estimates. It is demonstrated that for real time NDE scanning, the Extended Kalman Filter is a more sensible choice given the high computational overhead for the Particle filter.
Choi, Jin Woo; Lee, Jae Young; Hwang, Eui Jin; Hwang, In Pyeong; Woo, Sung Min; Lee, Chang Joo; Park, Eun Joo; Choi, Byung Ihn [Dept. of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of)
2014-10-15
The aim of this study was to evaluate the safety and accuracy of a new portable ultrasonography-guided high-intensity focused ultrasound (USg-HIFU) system with a 3-dimensional (3D) electronic steering transducer, a simultaneous ablation and imaging module, real-time cavitation monitoring, and 3D image reconstruction algorithms. To address the accuracy of the transducer, hydrophones in a water chamber were used to assess the generation of sonic fields. An animal study was also performed in five pigs by ablating in vivo thighs by single-point sonication (n=10) or volume sonication (n=10) and ex vivo kidneys by single-point sonication (n=10). Histological and statistical analyses were performed. In the hydrophone study, peak voltages were detected within 1.0 mm from the targets on the y- and z-axes and within 2.0-mm intervals along the x-axis (z-axis, direction of ultrasound propagation; y- and x-axes, perpendicular to the direction of ultrasound propagation). Twenty-nine of 30 HIFU sessions successfully created ablations at the target. The in vivo porcine thigh study showed only a small discrepancy (width, 0.5-1.1 mm; length, 3.0 mm) between the planning ultrasonograms and the pathological specimens. Inordinate thermal damage was not observed in the adjacent tissues or sonic pathways in the in vivo thigh and ex vivo kidney studies. Our study suggests that this new USg-HIFU system may be a safe and accurate technique for ablating soft tissues and encapsulated organs.
Channel-based real-time scheduling algorithm for WiMAX system%基于信道状态的WiMAX系统实时调度算法
冯慧芳; 赵亮; 陈媛媛
2013-01-01
This paper introduced three classic real-time scheduling algorithm named M-LWDF, EXP and CD-EDD. Then it proposed a real-time scheduling algorithm called CBRTS which based on the channel condition. The main idea of the algorithm was to find a more reasonable distribution of limited wireless resources for the users by analyzing the transmission conditions of the physical layer. The simulation results show that the CBRTS algorithm can reach higher throughput, smaller delay and packet loss rate, and are able to meet the QoS requirements of real-time businesses.%介绍了M-LWDF、EXP和CD-EDD三种经典的实时调度算法,并在此基础上提出一种基于信道状态的WiMAX系统的实时调度算法CBRTS(channel-based real-time scheduling).该算法核心思想是在数据链路层中考察物理层信道的传输条件,从而进一步将有限的无线资源更加合理地分配给用户.仿真结果表明,提出的算法具有更高的吞吐量、更小的时延和丢包率,能满足实时业务的QoS要求.
谭冠政; 贺欢; SLOMAN Aaron
2007-01-01
A novel method for the real-time globally optimal path planning of mobile robots is proposed based on the ant colony system (ACS) algorithm. This method includes three steps: the first step is utilizing the MAKLINK graph theory to establish the free space model of the mobile robot, the second step is utilizing the Dijkstra algorithm to find a sub-optimal collision-free path,and the third step is utilizing the ACS algorithm to optimize the location of the sub-optimal path so as to generate the globally optimal path. The result of computer simulation experiment shows that the proposed method is effective and can be used in the real-time path planning of mobile robots. It has been verified that the proposed method has better performance in convergence speed, solution variation, dynamic convergence behavior, and computational efficiency than the path planning method based on the genetic algorithm with elitist model.
CERN. Geneva; ANDERSON, Dustin James; DOGLIONI, Caterina
2015-01-01
The LHC provides experiments with an unprecedented amount of data. Experimental collaborations need to meet storage and computing requirements for the analysis of this data: this is often a limiting factor in the physics program that would be achievable if the whole dataset could be analysed. In this talk, I will describe the strategies adopted by the LHCb, CMS and ATLAS collaborations to overcome these limitations and make the most of LHC data: data parking, data scouting, and real-time analysis.
Pesaran, M. Hashem; Timmermann, Allan
2004-01-01
This paper considers the problems facing decision makers using econometric models in real time. It identifies the key stages involved and highlights the role of automated systems in reducing the effect of data snooping. It sets out many choices that researchers face in construction of automated systems and discusses some of the possible ways advanced in the literature for dealing with them. The role of feedbacks from the decision maker?s actions to the data generating process is also discusse...
Walker, R.; Gupta, N.
1984-01-01
The important algorithm issues necessary to achieve a real time flutter monitoring system; namely, the guidelines for choosing appropriate model forms, reduction of the parameter convergence transient, handling multiple modes, the effect of over parameterization, and estimate accuracy predictions, both online and for experiment design are addressed. An approach for efficiently computing continuous-time flutter parameter Cramer-Rao estimate error bounds were developed. This enables a convincing comparison of theoretical and simulation results, as well as offline studies in preparation for a flight test. Theoretical predictions, simulation and flight test results from the NASA Drones for Aerodynamic and Structural Test (DAST) Program are compared.
The entity-to-algorithm allocation problem: Extending the analysis
Grobler, J
2014-12-01
Full Text Available This paper extends the investigation into the algorithm selection problem in hyper-heuristics, otherwise referred to as the entity-to-algorithm allocation problem, introduced by Grobler et al.. Two newly developed population-based portfolio...
Real-time streamflow conditions
Graczyk, David J.; Gebert, Warren A.
1996-01-01
Would you like to know streamflow conditions before you go fishing in Wisconsin or in more distant locations? Real-time streamflow data throughout Wisconsin and the United States are available on the Internet from the U.S. Geological Survey. You can see if the stream you are interested in fishing is high due to recent rain or low because of an extended dry spell. Flow conditions at more than 100 stream-gaging stations located throughout Wisconsin can be viewed by accessing the Wisconsin District Home Page at: http://wwwdwimdn.er.usgs.gov
Real time Faraday spectrometer
Smith, Jr., Tommy E.; Struve, Kenneth W.; Colella, Nicholas J.
1991-01-01
This invention uses a dipole magnet to bend the path of a charged particle beam. As the deflected particles exit the magnet, they are spatially dispersed in the bend-plane of the magnet according to their respective momenta and pass to a plurality of chambers having Faraday probes positioned therein. Both the current and energy distribution of the particles is then determined by the non-intersecting Faraday probes located along the chambers. The Faraday probes are magnetically isolated from each other by thin metal walls of the chambers, effectively providing real time current-versus-energy particle measurements.
Block, R.K.; Krischer, W.; Lone, S. [CERN, Geneva (Switzerland)
1989-04-01
In the context of the LAA detector development program a subgroup Real Time Data Processing has tackled the problem of intelligent triggering. The main goal of this group is to show how fast digital devices, implemented as custom-made or commercial processors, can execute some basic algorithms, and how they can be embedded in the data flow between detector readout components and fully programmable commercial processors, which are expected to be the final data processing filter in real time.
Real time production optimization
Saputelli, Luigi; Otavio, Joao; Araujo, Turiassu; Escorcia, Alvaro [Halliburton, Houston, TX (United States). Landmark Division
2004-07-01
Production optimization encompasses various activities of measuring, analyzing, modeling, prioritizing and implementing actions to enhance productivity of a field. We present a state-of-the-art framework for optimizing production on a continuous basis as new sensor data is acquired in real time. Permanently acquired data is modeled and analyzed in order to create predictive models. A model based control strategy is used to regulate well and field instrumentation. The optimum field operating point, which changes with time, satisfies the maximum economic return. This work is a starting point for further development in automatic, intelligent reservoir technologies which get the most out of the abilities of permanent, instrumented wells and remotely activated downhole completions. The strategy, tested with history-matched data from a compartmentalised giant field, proved to reduce operating costs while increasing oil recovery by 27% in this field. (author)
Real time production optimization
Saputelli, Luigi; Otavio, Joao; Araujo, Turiassu; Escorcia, Alvaro [Halliburton, Houston, TX (United States). Landmark Division
2004-07-01
Production optimization encompasses various activities of measuring, analyzing, modeling, prioritizing and implementing actions to enhance productivity of a field. We present a state-of-the-art framework for optimizing production on a continuous basis as new sensor data is acquired in real time. Permanently acquired data is modeled and analyzed in order to create predictive models. A model based control strategy is used to regulate well and field instrumentation. The optimum field operating point, which changes with time, satisfies the maximum economic return. This work is a starting point for further development in automatic, intelligent reservoir technologies which get the most out of the abilities of permanent, instrumented wells and remotely activated downhole completions. The strategy, tested with history-matched data from a compartmentalised giant field, proved to reduce operating costs while increasing oil recovery by 27% in this field. (author)
An Extended Algorithm of Flexibility Analysis in Chemical Engineering Processes
无
2001-01-01
An extended algorithm of flexibility analysis with a local adjusting method for flexibility region of chemical processes, which is based on the active constraint strategy, is proposed, which fully exploits the flexibility region of the process system operation. The hyperrectangular flexibility region determined by the extended algorithm is larger than that calculated by the previous algorithms. The limitation of the proposed algorithm due to imperfect convexity and its corresponding verification measure are also discussed. Both numerical and actual chemical process examples are presented to demonstrate the effectiveness of the new algorithm.
A novel extended kernel recursive least squares algorithm.
Zhu, Pingping; Chen, Badong; Príncipe, José C
2012-08-01
In this paper, a novel extended kernel recursive least squares algorithm is proposed combining the kernel recursive least squares algorithm and the Kalman filter or its extensions to estimate or predict signals. Unlike the extended kernel recursive least squares (Ex-KRLS) algorithm proposed by Liu, the state model of our algorithm is still constructed in the original state space and the hidden state is estimated using the Kalman filter. The measurement model used in hidden state estimation is learned by the kernel recursive least squares algorithm (KRLS) in reproducing kernel Hilbert space (RKHS). The novel algorithm has more flexible state and noise models. We apply this algorithm to vehicle tracking and the nonlinear Rayleigh fading channel tracking, and compare the tracking performances with other existing algorithms.
杨永军; 徐江; 舒逸; 许帅
2012-01-01
Real-time database has been widely applied in industrial process control field, in which historical data costs vast space. In order to increase the capacity of database while keeping the characteristic of high speed, data compression technology is adopted into real-time database. This paper designs a new lossless data compression algorithm for historical data of real-time database which is based on LZ algorithm. The experiments indicate that this algorithm achieves small amount of computation, high compression ratio and fast compression speed.%实时数据库在工业控制领域得到广泛应用,其保存的历史数据占用大量的存储空间.为了在保持高实时性等特点的同时,尽可能地提高数据库的容量,数据压缩技术被引入实时数据库.本文设计一种针对实时数据库历史数据的无损压缩算法,该算法改进自LZ算法.通过试验比较发现这种算法运算量小、压缩率高、压缩速度快,是一种高效的无损压缩算法.
National Oceanic and Atmospheric Administration, Department of Commerce — The Ovation Prime Real-Time (OPRT) product is a real-time forecast and nowcast model of auroral power and is an operational implementation of the work by Newell et...
Multiprocessor scheduling for real-time systems
Baruah, Sanjoy; Buttazzo, Giorgio
2015-01-01
This book provides a comprehensive overview of both theoretical and pragmatic aspects of resource-allocation and scheduling in multiprocessor and multicore hard-real-time systems. The authors derive new, abstract models of real-time tasks that capture accurately the salient features of real application systems that are to be implemented on multiprocessor platforms, and identify rules for mapping application systems onto the most appropriate models. New run-time multiprocessor scheduling algorithms are presented, which are demonstrably better than those currently used, both in terms of run-time efficiency and tractability of off-line analysis. Readers will benefit from a new design and analysis framework for multiprocessor real-time systems, which will translate into a significantly enhanced ability to provide formally verified, safety-critical real-time systems at a significantly lower cost.
陈立福; 汪丙南; 向茂生
2011-01-01
This paper presents a new algorithm to generate the interferometry fringe with high quality in real-time. It utilizes the techniques of down-sampling and interferometry multi-look processing, the look-up table with linear interpolation, the ECS auto-registration imaging algorithm with non-linear approximation,the real-time interferometry motion compensation,and the improved fast algorithm of computing coherence and filtering the interferometry fringe. The feasibility of generating the interferometry fringe in real-time with hardware is 8nalyzed and the structure of hardware is given to realize the algorithm too. In the end,the interferometry fringe and coherence map are generated by the algorithm for the airborne X-band InSAR dato of Institute of Electronics, Chinese Academy of Sciences,and the results prove the validity of the algorithm.%为了能实时产生高质量的干涉条纹提出了一种新算法.算法采用了降采样与干涉多视处理相结合的技术、线性插值查表法、非线性近似的ECS自配准成像算法、实时干涉运补、相干系数快速计算以及快速干涉滤波方法,并对该算法实时产生干涉条纹的可行性进行了分析,给出了实现该算法的硬件结构.最后针对电子所X波段机载双天线InSAR数据,利用该算法产生了干步条纹和相干系数图,证明了算法的有效性.
Real-time surface tracking system using common-path spectral domain optical coherence tomography
Kim, Keo-Sik; Park, Hyoung-Jun; Kang, Hyun Seo; Kang, Jin U.; Song, Chul-Gyu
2012-11-01
An enhanced surface tracking system based on optical coherence tomography (OCT) modality has been developed and tested for use in a surgical guidance system. A surface detection algorithm based on a Savitzky-Golay filter of A-scan data and thresholding was applied to real-time depth tracking. The algorithm output controlled a motorized stage to adjust the probe position according to the sample's topological variance in real-time. As a result, the root mean square error (RMSE: 4.2 μm) of our algorithm was relatively lower than the conventional method (RMSE: 16.6 μm). Also, OCT images obtained using the algorithm showed a significantly extended imaging range and active surface tracking in real time. Consequently, the devised method demonstrated potential for use in systems for guiding surgical robots and endoscopic OCT.
An extended EM algorithm for subspace clustering
Lifei CHEN; Qingshan JIANG
2008-01-01
Clustering high dimensional data has become a challenge in data mining due to the curse of dimension-ality. To solve this problem, subspace clustering has been defined as an extension of traditional clustering that seeks to find clusters in subspaces spanned by different combinations of dimensions within a dataset. This paper presents a new subspace clustering algorithm that calcu-lates the local feature weights automatically in an EM-based clustering process. In the algorithm, the features are locally weighted by using a new unsupervised weight-ing method, as a means to minimize a proposed cluster-ing criterion that takes into account both the average intra-clusters compactness and the average inter-clusters separation for subspace clustering. For the purposes of capturing accurate subspace information, an additional outlier detection process is presented to identify the pos-sible local outliers of subspace clusters, and is embedded between the E-step and M-step of the algorithm. The method has been evaluated in clustering real-world gene expression data and high dimensional artificial data with outliers, and the experimental results have shown its effectiveness.
周姗姗; 柴金广; 李丹
2011-01-01
针对探测系统跟踪误差对目标跟踪的影响,提出一种实时递推的最小二乘预测跟踪算法.该算法采用平方预测器的估算方式,获得目标运动轨迹的最佳逼近,通过不断更新的历史数据实时递推轨迹参数,预测下一帧目标位置.该算法采用Matlab软件编写易于工程实现的应用程序.得到仿真的目标真实轨迹与预测轨迹数据.仿真结果表明,该算法可以在系统延迟、目标机动的情况下实时快速地预测目标位置,降低跟踪误差.%To deal with the tracking error of observation system for target tracing, a novel predicted tracking algorithm which is based on least square principle in real-time recursively is presented. The algorithm chooses the square prediction as the estimation method to obtain the optimal approximation of the target motion trajectory. The algorithm updates recursive trajectory parameters based on the historical data in real-time, and then predicts the target position of next frame. The algorithm uses Matlab to program the application which is easy to realize for the practical project. According to an given example, the simulation of real trajectory and predicted trajectory are given. The simulation results show that the algorithm can predict the target position quickly and in real-time in the case of system delay or target maneuver, and reduce the tracking error.
A note on extending decision algorithms by stable predicates
Alfredo Ferro
1988-11-01
Full Text Available A general mechanism to extend decision algorithms to deal with additional predicates is described. The only conditions imposed on the predicates is stability with respect to some transitive relations.
Real-Time Visualization of Tissue Ischemia
Bearman, Gregory H. (Inventor); Chrien, Thomas D. (Inventor); Eastwood, Michael L. (Inventor)
2000-01-01
A real-time display of tissue ischemia which comprises three CCD video cameras, each with a narrow bandwidth filter at the correct wavelength is discussed. The cameras simultaneously view an area of tissue suspected of having ischemic areas through beamsplitters. The output from each camera is adjusted to give the correct signal intensity for combining with, the others into an image for display. If necessary a digital signal processor (DSP) can implement algorithms for image enhancement prior to display. Current DSP engines are fast enough to give real-time display. Measurement at three, wavelengths, combined into a real-time Red-Green-Blue (RGB) video display with a digital signal processing (DSP) board to implement image algorithms, provides direct visualization of ischemic areas.
Real-time focal stack compositing for handheld mobile cameras
Solh, Mashhour
2013-03-01
Extending the depth of field using a single lens camera on a mobile device can be achieved by capturing a set of images each focused at a different depth or focal stack then combine these samples of the focal stack to form a single all-in-focus image or an image refocused at a desired depth of field. Focal stack compositing in real time for a handheld mobile camera has many challenges including capturing, processing power, handshaking, rolling shutter artifacts, occlusion, and lens zoom effect. In this paper, we describe a system for a real time focal stack compositing system for handheld mobile device with an alignment and compositing algorithms. We will also show all-in-focus images captured and processed by a cell phone camera running on Android OS.
An Effective Real-Time Cut Detection Algorithm%一种高速切变镜头边界探测算法
王伟强; 高文; 马继涌
2001-01-01
Shot boundary detection is a key technique in constructing video information management system. The paper proposes a fast and effective cut detection algorithm in compressed domain. Compared with other algorithms in compressed domain, the algorithm applies multi-resolution detection mode,distinct from the common comparison mode between consecutive frames. The mechanism makes the volume of data processed decrease greatly in the whole detection process. The algorithm also uses the different raw information,which can be extracted directly from frames with different coding types,as features to reduce computation complexity. To verify the validity of the algorithm, we did experiments on a data set containing 145,000 frames. The experiment results demonstrate the algorithm has not only a very fast detection speed,as 2.5 to 5.2 times fast as others' in compressed domain,but also average 98% accuracy and recall.
黄金; 许渤; 凌云; 邱昆
2013-01-01
与传统的商业网络不同,航空机载波分复用网络要求强实时性以保证消息的传输性能.实时调度算法是保证机载网络中消息传输性能的关键.针对机载波分复用网络的实时性要求,采用实时通信中的周期性任务模型,提出了满足机载波分复用网络实时性要求的加权轮转调度算法,其中轮转周期的选择、权值匹配方法和多信道分配方法是影响调度算法参数设计的重要过程.通过多信道分配方法有效减少了消息拆分次数；结合实例比较确定了算法中消息分配权值的计算方法；并指出了最优轮转周期无法保证最小的消息延迟时间率.研究结果对机载波分复用网络的工程设计与优化有一定的指导意义.%Different from the commercial applications, the avionic wavelength division multiplexing (WDM) network lays much emphasis on hard real-time characteristics. The real-time scheduling algorithm is a key issue to ensure the message transmission performance. According to the real-time communication requirement of avionic WDM network and the traffic characteristics of the avionic network, a weighted round robin scheduling algorithm is proposed based on the periodic task model of real-time communication to guarantee hard real-time transmission in an airborne WDM network, which is comprised of the rotation cycle selection, weights assignment scheme and multi-channel allocation method. Among them, multi-channel allocation method efficiently reduces the splitting times of the message-, combined with examples, message weights assignment scheme is determined and it is pointed out that the optimal rotation cycle cannot guarantee the minimum message delay ratio. Research results are meaningful for the design of real-time scheduling parameters and the current practice of avionic WDM network.
A potential reduction algorithm for an extended SDP problem
聂家旺; 袁亚湘
2000-01-01
An extended semi-definite programming, the SDP with an additional quadratic term in the objective function, is studied. Our generalization is similar to the generalization from linear programming to quadratic programming. Optimal conditions for this new class of problems are discussed and a potential reduction algorithm for solving QSDP problems is presented. The convergence properties of this algorithm are also given.
Extending CTL with actions and real time
Jansen, D.N.; Wieringa, Roelf J.
We present the logic ATCTL, which is intended to be used for model checking models that have been specified in a lightweight version of the Unified Modelling Language (UML). Elsewhere, we have defined a formal semantics for LUML to describe the models. This paper's goal is to give a specification
简毅; 魏磊; 杨亚联; 刘其鑫
2015-01-01
为了保证CAN总线网络中实时性消息的截止期，同时减小紧迫性消息的传输延迟，综合考虑了CAN网络中实时消息的截止期和价值度两个参数，提出了截止期-价值度优先( Deadline-Value First)实时调度算法，简称DVF算法。给出了算法遵循原则和设计过程，对截止期因素进行分段线性处理的方法，使得算法在保证消息截止期的前提下尽量让关键性消息优先发送。以 EDF 算法和HVF( higest value first)算法为基准，从关键消息的相对延迟、丢帧率和丢失价值率这三个方面对DVF算法进行性能分析，实验表明DVF算法相比于EDF算法和HVF算法有很大改善。%In order to guarantee the deadline of real-time message in CAN network and reduce the transmis-sion delay of Emergency messages, a real-time scheduling algorithm named DVF ( Deadline-Value First) is proposed, Considered deadline and value of real-time message in CAN network. The Principle and way of the algorithm is given. By disposing the deadline element in subsection-linear method, this algorithm can send the most critical message firstly with no loss of other message’ s deadline. The performance of the DVF (deadline-value first) algorithms is analyzed by comparing it with EDF(earliest deadline first) algorithm and HVF ( highest value first) algorithm based on value lose ratio, miss message ratio and relative transmis-sion delay. The experiment shows that HVF algorithms can improve the performance compared to the classi-cal EDF algorithm and HVF algorithm under all workload conditions.
REAL TIME SYSTEM OPERATIONS 2006-2007
Eto, Joseph H.; Parashar, Manu; Lewis, Nancy Jo
2008-08-15
The Real Time System Operations (RTSO) 2006-2007 project focused on two parallel technical tasks: (1) Real-Time Applications of Phasors for Monitoring, Alarming and Control; and (2) Real-Time Voltage Security Assessment (RTVSA) Prototype Tool. The overall goal of the phasor applications project was to accelerate adoption and foster greater use of new, more accurate, time-synchronized phasor measurements by conducting research and prototyping applications on California ISO's phasor platform - Real-Time Dynamics Monitoring System (RTDMS) -- that provide previously unavailable information on the dynamic stability of the grid. Feasibility assessment studies were conducted on potential application of this technology for small-signal stability monitoring, validating/improving existing stability nomograms, conducting frequency response analysis, and obtaining real-time sensitivity information on key metrics to assess grid stress. Based on study findings, prototype applications for real-time visualization and alarming, small-signal stability monitoring, measurement based sensitivity analysis and frequency response assessment were developed, factory- and field-tested at the California ISO and at BPA. The goal of the RTVSA project was to provide California ISO with a prototype voltage security assessment tool that runs in real time within California ISO?s new reliability and congestion management system. CERTS conducted a technical assessment of appropriate algorithms, developed a prototype incorporating state-of-art algorithms (such as the continuation power flow, direct method, boundary orbiting method, and hyperplanes) into a framework most suitable for an operations environment. Based on study findings, a functional specification was prepared, which the California ISO has since used to procure a production-quality tool that is now a part of a suite of advanced computational tools that is used by California ISO for reliability and congestion management.
Houy, P
1999-10-15
The aim of this work is to propose a real-time control of the current profile in order to achieve reproducible operating modes with improved energetic confinement in tokamaks. The determination of the profile is based on measurements given by interferometry and polarimetry diagnostics. Different ways to evaluate and improve the accuracy of these measurements are exposed. The position and the shape of a plasma are controlled by the poloidal system that forces them to cope with standard values. Gas or neutral ions or ice pellet or extra power injection are technical means used to control other plasma parameters. These controls are performed by servo-controlled loops. The poloidal system of Tore-supra is presented. The main obstacle to a reliable determination of the current profile is the fact that slightly different Faraday angles lead to very different profiles. The direct identification method that is exposed in this work, gives the profile that minimizes the square of the margin between measured and computed values. The different algorithms proposed to control current profiles on Tore-supra have been validated by using a plasma simulation. The code Cronos that solves the resistive diffusion equation of current has been used. (A.C.)
李致远; 朱求志; 吴永焜; 唐振宇; 胡华明
2014-01-01
Anomaly detection can detect new and unknown attacks,which has great significance on the wireless sensor networks security. Nowadays,the proposed anomaly detection schemes has poor real-time,high false positive rate and the large amount of computational overhead, and hence the schemes are not suitable for wireless sensor networks. In this paper,a wavelet analysis-based real-time anomaly detection ( Wavelet Analysis-based Real-time Anomaly Detection, WARAD) algorithm for wireless sensor network is proposed. Throughout the detecting process, the WARAD algorithm reversely collects the real-time network traffic,and then uses the variance of the wavelet coefficients in the small-scale interval to compute the Hurst values,which can improve the real-time and the accuracy of anomaly detection,and reduce the computational complexity of solving the Hurst values. Finally,the WARAD algorithm-based intrusion detection system is implemented on the platform of MeshIDE. The experimental results showed that the proposed algorithm greatly improved the real-time of anomaly detection for wireless sensor networks,and reduced the false positive rate and the false negative rate of anomaly detection.%异常检测技术能够检测到未知攻击,对于保障无线传感器网络安全具有重要意义。当前的异常检测技术实时性差,误报率高且计算量大,因此,无法直接应用在无线传感器网络中。鉴于此,提出基于小波分析的实时无线传感网异常检测( Wavelet Analysis-Based Real-time Anomaly Detection,WARAD)算法。在整个检测过程中, WARAD算法采用了逆向获取实时网络流量,然后通过对小尺度区间使用小波系数方差法计算Hurst值,从而提高异常检测的实时性、准确率,并降低求解Hurst值的运算复杂度。最后,在MeshIDE平台上实现了基于WARAD算法的异常检测系统,实验结果表明此算法极大地提高了无线传感网环境下异常检测的实时性,并降低了异常检测的误报率和漏报率。
Designing Real Time Assistive Technologies
Sonne, Tobias; Obel, Carsten; Grønbæk, Kaj
2015-01-01
design criteria in relation to three core components (sensing, recognizing, and assisting) for designing real time assistive technologies for children with ADHD. Based on these design criteria, we designed the Child Activity Sensing and Training Tool (CASTT), a real time assistive prototype that captures...... activities and assists the child in maintaining attention. From a preliminary evaluation of CASTT with 20 children in several schools, we and found that: 1) it is possible to create a wearable sensor system for children with ADHD that monitors physical and physiological activities in real time; and that 2......) real time assistive technologies have potential to assist children with ADHD in regaining attention in critical school situations....
Designing Real Time Assistive Technologies
Sonne, Tobias; Obel, Carsten; Grønbæk, Kaj
design criteria in relation to three core components (sensing, recognizing, and assisting) for designing real time assistive technologies for children with ADHD. Based on these design criteria, we designed the Child Activity Sensing and Training Tool (CASTT), a real time assistive prototype that captures...... activities and assists the child in maintaining attention. From a preliminary evaluation of CASTT with 20 children in several schools, we and found that: 1) it is possible to create a wearable sensor system for children with ADHD that monitors physical and physiological activities in real time; and that 2......) real time assistive technologies have potential to assist children with ADHD in regaining attention in critical school situations....
Real-time resource allocation algorithm on high-speed train mobile network%用于高速列车移动网络的资源分配实时算法
张永晖; 蒋新华; 林漳希
2012-01-01
High -speed train mobile scenarios is fitted to adopted multi-homing delay tolerant mobile network, alleviating high error rate and frequent disruptions effectively. However, its resource allocation algorithms on it are of computational complexity and poor real-time. Give an Initialization resource allocation algorithm, and ensure every step utility of processes non-decreasing with utility differential, gains O(n) algorithm time complexity.%误码率高、频繁中断的高速列车移动场景宜采用多宿主容迟网络.但其资源分配计算复杂,实时性较差.基于效用差分法设计初始化过程资源分配算法,以保证过程中每一步的效用单调不减,算法时间复杂度降至O(n).
周本海; 乔建忠; 林树宽
2012-01-01
With low power consumption and high performance characteristics, multi-core processors have occupied the main market. Aiming at parallel real time scheduling on multi-core platform, a scheduling algorithm combined with local and global EDF was proposed. The budgets, deadline partition, and task migration time were decided by the proposed CPU width reserved server. A memory allocation method was presented, which could manage the memory resources for parallel real time tasks effectively. Experimental results showed that the proposed new scheduling algorithm has a higher scheduling success rate. In addition, using the presented memory partition algorithm, real-time characteristics and stability of tasks were assured in memory competition situation .%多核处理器凭借着低功耗高性能的优势占据了市场.针对多核平台上并行实时任务,提出局部与全局EDF相结合的调度算法,其中任务的截止期划分、执行预算以及迁移时机由所设计的处理器带宽预留服务器决定.同时,提出了内存分配算法,该算法能够更好地为并行实时任务管理内存资源.实验结果表明新的调度算法具有更高的调度成功率.另外,在内存资源竞争的前提下,内存分配算法可以保证并行任务的实时性与系统稳定性.
STEGANOGRAPHY FOR TWO AND THREE LSBs USING EXTENDED SUBSTITUTION ALGORITHM
R.S. Gutte
2013-03-01
Full Text Available The Security of data on internet has become a prior thing. Though any message is encrypted using a stronger cryptography algorithm, it cannot avoid the suspicion of intruder. This paper proposes an approach in such way that, data is encrypted using Extended Substitution Algorithm and then this cipher text is concealed at two or three LSB positions of the carrier image. This algorithm covers almost all type of symbols and alphabets. The encrypted text is concealed variably into the LSBs. Therefore, it is a stronger approach. The visible characteristics of the carrier image before and after concealment remained almost the same. The algorithm has been implemented using Matlab.
Real Time Implementation Of Face Recognition System
Megha Manchanda
2014-10-01
Full Text Available This paper proposes face recognition method using PCA for real time implementation. Nowadays security is gaining importance as it is becoming necessary for people to keep passwords in their mind and carry cards. Such implementations however, are becoming less secure and practical, also is becoming more problematic thus leading to an increasing interest in techniques related to biometrics systems. Face recognition system is amongst important subjects in biometrics systems. This system is very useful for security in particular and has been widely used and developed in many countries. This study aims to achieve face recognition successfully by detecting human face in real time, based on Principal Component Analysis (PCA algorithm.
基于自适应投影矩阵的实时视频拼接算法%A REAL-TIME VIDEO STITCHING ALGORITHM BASED ON ADAPTIVE PROJECTION MATRIX
刘明杰; 任帅; 金城
2012-01-01
In this paper, a fast algorithm is proposed to stitch video in real-time with high visual quality. This algorithm can be divided into two stages; the background stage and the real-time stage. The background stage runs every few seconds. In this stage, the algorithm extracts frame features from time-synchronised video streams and estimates projection matrix using RANSAC and LM algorithm. In real-time stage, the accumulated error in regard to the tracked pairs of key points is calculated by projection matrix, where the pairs of key points are tracked using optical flow algorithm and the pairs of feature points used are got from previous frame. If the error is larger than certain threshold or there are not enough pairs of key points tracked, the background stage will be run once again. Once the projection matrix i9 got, an effect nonlinear blending method is taken to blend the videos. By using these procedures, this algorithm can work fast and well even the cameras are moving. Results of experiment show that this algorithm can improve stitching speed greatly with good quality.%提出一种快速的算法用于高质量的实时拼接视频.算法分为两个阶段:后台阶段和实时阶段.后台阶段每隔一定周期运行,从同步的视频流中提取图像特征,采用RANSAC和LM算法计算投影矩阵.在实时阶段,采用从前一帧中得到的特征点点对,用光流法跟踪匹配点对的方法,对跟踪得到的点对由投影矩阵计算得到图像误差.若误差超过一定阈值或跟踪到点对数目太少,后台阶段就会再次执行.一旦得到了投影矩阵,就采取一种非线性的融合算法对视频进行融合.通过以上步骤,即使摄像头移动,算法也能运行快速.实验结果显示该算法大大改善了速度,而且拼接质量也很好.
Nasehi, Saadat; Pourghassem, Hossein
2012-08-01
This paper proposes a novel real-time patient-specific seizure diagnosis algorithm based on analysis of electroencephalogram (EEG) and electrocardiogram (ECG) signals to detect seizure onset. In this algorithm, spectral and spatial features are selected from seizure and non-seizure EEG signals by Gabor functions and principal component analysis (PCA). Furthermore, four features based on heart rate acceleration are extracted from ECG signals to form feature vector. Then a neural network classifier based on improved particle swarm optimization (IPSO) learning algorithm is developed to determine an optimal nonlinear decision boundary. This classifier allows to adjust the parameters of the neural network classifier, efficiently. This algorithm can automatically detect the presence of seizures with minimum delay which is an important factor from a clinical viewpoint. The performance of the proposed algorithm is evaluated on a dataset consisting of 154 h records and 633 seizures from 12 patients. The results indicate that the algorithm can recognize the seizures with the smallest latency and higher good detection rate (GDR) than other presented algorithms in the literature.
Interactive Real-time Magnetic Resonance Imaging
Brix, Lau
seeks to implement and assess existing reconstruction algorithms using multi-processors of modern graphics cards and many-core computer processors and to cover some of the potential clinical applications which might benefit from using an interactive real-time MRI system. First an off......-line, but interactive, slice alignment tool was used to support the notion that 3D blood flow quantification in the heart possesses the ability to obtain curves and volumes which are not statistical different from standard 2D flow. Secondly, the feasibility of an interactive real-time MRI system was exploited...... with regard to optimal sampling strategy for detecting motion in four different anatomies on two different MRI scanner brands. A fully implemented interactive real-time MRI system was exploited in a group of healthy fetuses and proved its eligibility as an alternative diagnostic tool for fetal imaging...
Real-time robust signal space separation for magnetoencephalography.
Guo, Chenlei; Li, Xin; Taulu, Samu; Wang, Wei; Weber, Douglas J
2010-08-01
In this paper, we develop a robust signal space separation (rSSS) algorithm for real-time magnetoencephalography (MEG) data processing. rSSS is based on the spatial signal space separation (SSS) method and it applies robust regression to automatically detect and remove bad MEG channels so that the results of SSS are not distorted. We extend the existing robust regression algorithm via three important new contributions: 1) a low-rank solver that efficiently performs matrix operations; 2) a subspace iteration scheme that selects bad MEG channels using low-order spherical harmonic functions; and 3) a parallel computing implementation that simultaneously runs multiple tasks to further speed up numerical computation. Our experimental results based on both simulation and measurement data demonstrate that rSSS offers superior accuracy over the traditional SSS algorithm, if the MEG data contain significant outliers. Taking advantage of the proposed fast algorithm, rSSS achieves more than 75 x runtime speedup compared to a direct solver of robust regression. Even though rSSS is currently implemented with MATLAB, it already provides sufficient throughput for real-time applications.
Extended SVM algorithms for multilevel trans-Z-source inverter
Aida Baghbany Oskouei
2016-03-01
Full Text Available This paper suggests extended algorithms for multilevel trans-Z-source inverter. These algorithms are based on space vector modulation (SVM, which works with high switching frequency and does not generate the mean value of the desired load voltage in every switching interval. In this topology the output voltage is not limited to dc voltage source similar to traditional cascaded multilevel inverter and can be increased with trans-Z-network shoot-through state control. Besides, it is more reliable against short circuit, and due to several number of dc sources in each phase of this topology, it is possible to use it in hybrid renewable energy. Proposed SVM algorithms include the following: Combined modulation algorithm (SVPWM and shoot-through implementation in dwell times of voltage vectors algorithm. These algorithms are compared from viewpoint of simplicity, accuracy, number of switching, and THD. Simulation and experimental results are presented to demonstrate the expected representations.
Search-Space Characterization for Real-time Heuristic Search
Huntley, Daniel; Bulitko, Vadim
2013-01-01
Recent real-time heuristic search algorithms have demonstrated outstanding performance in video-game pathfinding. However, their applications have been thus far limited to that domain. We proceed with the aim of facilitating wider applications of real-time search by fostering a greater understanding of the performance of recent algorithms. We first introduce eight algorithm-independent complexity measures for search spaces and correlate their values with algorithm performance. The complexity ...
Marinescu, Sorin Ovidiu; Tamas-Selicean, Domitian; Acretoaie, Vlad;
In this paper we are interested in the timing analysis of mixed-criticality embedded real-time applications mapped on distributed heterogeneous architectures. Mixedcriticality tasks can be integrated onto the same architecture only if there is enough spatial and temporal separation among them. We...... in partitions using fixedpriority preemptive scheduling. We have extended the stateof- the-art algorithms for schedulability analysis to take into account the partitions. The proposed algorithm has been evaluated using several synthetic and real-life benchmarks....
Resource Allocation in Public Cluster with Extended Optimization Algorithm
Akbar, Z.; Handoko, L. T.
2007-01-01
We introduce an optimization algorithm for resource allocation in the LIPI Public Cluster to optimize its usage according to incoming requests from users. The tool is an extended and modified genetic algorithm developed to match specific natures of public cluster. We present a detail analysis of optimization, and compare the results with the exact calculation. We show that it would be very useful and could realize an automatic decision making system for public clusters.
Marzbanrad, Javad; Tahbaz-zadeh Moghaddam, Iman
2016-09-01
The main purpose of this paper is to design a self-tuning control algorithm for an adaptive cruise control (ACC) system that can adapt its behaviour to variations of vehicle dynamics and uncertain road grade. To this aim, short-time linear quadratic form (STLQF) estimation technique is developed so as to track simultaneously the trend of the time-varying parameters of vehicle longitudinal dynamics with a small delay. These parameters are vehicle mass, road grade and aerodynamic drag-area coefficient. Next, the values of estimated parameters are used to tune the throttle and brake control inputs and to regulate the throttle/brake switching logic that governs the throttle and brake switching. The performance of the designed STLQF-based self-tuning control (STLQF-STC) algorithm for ACC system is compared with the conventional method based on fixed control structure regarding the speed/distance tracking control modes. Simulation results show that the proposed control algorithm improves the performance of throttle and brake controllers, providing more comfort while travelling, enhancing driving safety and giving a satisfactory performance in the presence of different payloads and road grade variations.
A Real-time Road Boundary Detection Algorithm Based on Driverless Cars%一种智能汽车的实时道路边缘检测算法
朱学葵; 高美娟; 李尚年
2015-01-01
Pointing to road boundary detection problem of driverless cars in structured and semi-structured road, the paper proposed a new real-time road boundary detection algorithm based on driverless cars as a platform. The algorithm firstly includes the following steps:calibration, layering and median filtering will be made according to the obtained lidar point cloud data. And then the left and right road boundary point of each layer will be extracted. The extracted road boundary points are then straight line fitted using Ransac algorithm. Finally, straight line is tracked using Kalman filtering, thus the real-time road boundary detection is achieved. The test results show that this boundary detection algorithm is with high accuracy and reliability and is able to accurately accomplish the boundary detection task, which can satisfy the requirements of real-time system. And this algorithm has been applied successfully in "The Future Challenge Competition for Driverless Cars" 2014 and obtained the third place.%以无人驾驶汽车为平台,针对结构化、半结构化道路下无人驾驶汽车道路边缘检测问题,提出了一种智能汽车的实时道路边缘检测算法. 该算法首先对获取的激光雷达数据点云进行标定、分层与中值滤波,然后提取各层的左右边界点,而后利用随机抽样一致性算法(简称Ransac)对左右边界点集进行直线拟合,最后用卡尔曼滤波算法进行跟踪,从而实现实时的道路边缘检测. 经实验验证,该算法准确率高,可靠性强,能够准确完成道路边缘检测,可以满足实时系统的要求,并已经成功应用于2014年的"智能汽车未来挑战赛",而且取得了第三名的好成绩.
殷永峰; 郑本焘; 陆民燕; 倪红英
2011-01-01
将统一建模语言(unified modeling language,UML)和对象约束语言(object constraint language,OCL)引入嵌入式软件测试领域,首先提出了一种基于UML实时扩展的嵌入式软件测试建模过程.然后,给出了UML状态图和类图的实时扩展方法.最后,结合航空电子系统嵌入式软件测试用例生成过程,详细阐述了被测系统的静态和动态建模,提出了扩展的测试序列定义及其生成方法,最终将所生成测试用例采用扩展标记语言(extensible markup language,XML)格式存储.工程应用验证表明,上述方法可充分发挥UML作为工业标准的工具资源优势,提高嵌入式软件测试用例生成的准确性、有效性和自动化程度.%The unified modeling language (UML) and object constraint language (OCL) are introduced into the embedded software testing field, and the testing modeling process based on real-time extended UML are studied firstly. Then, the real-time extensive methods of UML state diagram and class diagram are presented.Finally, combined with the avionics embedded software test case generation practice, the static and dynamic modeling of software under test (SUT) are described in detail. Meanwhile, the definition of the extended test sequence and its generation method are put forward and the generated test cases are eventually stored using extensible markup language (XML). The project application verification result shows that the proposed method can fully make use of the advantages of tool resource of the UML which has been as the industry standard and improve the efficiency, accuracy and the automatic level of embedded software test case generation.
刘兴川; 张盛; 徐立强; 林孝康
2011-01-01
Received signal strength fluctuations are a major limit to positioning accuracy in complex outdoor environments.Conventional approaches use the temporal diversity and an average filter to reduce the signal strength fluctuations, which increases the latency in estimating the location so they cannot satisfy the demands of outdoor real-time positioning systems.A real-time algorithm for fingerprint positioning was developed based on an analysis of the spatial correlation of the received signal strength.The algorithm uses the spatial diversity to reduce the signal strength fluctuations and the positioning latency.The algorithm then uses the continuity of the movement trajectory to improve the positioning accuracy.Tests in outdoor environments indicate that the algorithm significantly improves fingerprint positioning performance.%在室外复杂环境下,接收信号强度的浮动是制约Fingerprint定位精度的一个主要问意.传统的方法利用时间分集和平均滤波器来减小信号的浮动,这增加了定位的廷迟,无法满足室外实时定位的需求.为了解决信号浮动和定位延迟问题,在分析接收信号强度空间相关性的基础上,提出了一种实时的Fingerprint定位算法,利用空间分集减小信号的浮动和定位延迟,同时根据运动物体轨迹的连续性提高定位精度.室外环境下的实验结果表明了所提算法能显著提高Fingerprint定位系统的性能.
Feng, Kaiqiang; Li, Jie; Zhang, Xiaoming; Shen, Chong; Bi, Yu; Zheng, Tao; Liu, Jun
2017-09-19
In order to reduce the computational complexity, and improve the pitch/roll estimation accuracy of the low-cost attitude heading reference system (AHRS) under conditions of magnetic-distortion, a novel linear Kalman filter, suitable for nonlinear attitude estimation, is proposed in this paper. The new algorithm is the combination of two-step geometrically-intuitive correction (TGIC) and the Kalman filter. In the proposed algorithm, the sequential two-step geometrically-intuitive correction scheme is used to make the current estimation of pitch/roll immune to magnetic distortion. Meanwhile, the TGIC produces a computed quaternion input for the Kalman filter, which avoids the linearization error of measurement equations and reduces the computational complexity. Several experiments have been carried out to validate the performance of the filter design. The results demonstrate that the mean time consumption and the root mean square error (RMSE) of pitch/roll estimation under magnetic disturbances are reduced by 45.9% and 33.8%, respectively, when compared with a standard filter. In addition, the proposed filter is applicable for attitude estimation under various dynamic conditions.
REAL-TIME LICENSING MANAGEMENT OF SECURE MULTIMEDIA CONTENT DELIVERY
马兆丰; 冯博琴
2004-01-01
Media Commerce is now becoming a new trend which results from faster development of network bandwidth and high availability of multimedia technologies, how to protect media content from being used in a right-violated way is one of most important issues to take into account. In this paper, a novel and efficient authorization and authentication Digital Rights Management (DRM) schema is proposed firstly for secure multimedia delivery, then based on the schema, a real-time digital signature algorithm built on Elliptic Curve Cryptography (ECC) is adopted for fast authentication and verification of licensing management, thus secure multimedia delivery via TCP/RTP can efficiently work with real-time transaction response and high Quality of Service (QoS) . Performance evaluations manifest the proposed schema is secure, available for real-time media stream authentication and authorization without much effected of QoS. The proposed schema is not only available for Client/Server media service but can be easily extended to P2P and broadcasting network for trusted rights management.
一种针对移动相机的实时视频背景减除算法%A Real-Time Background Subtraction Algorithm for Freely Moving Cameras
孙丰; 秦开怀; 孙伟; 郭华源
2016-01-01
提取移动相机拍摄视频中的前景时，采用基于稠密光流或像素点轨迹的算法估算相机运动会造成算法非常耗时，为此提出一种简单有效的实时视频背景减除算法。首先用基于超像素的区域增长预处理算法得到可能是前景的超像素；然后基于分块相对光流的背景特征点筛选算法来估算相机运动；最后检查光流与相机运动的一致性，得到背景减除的最终结果。实验结果表明，该算法可以实时处理大小为640×480像素的视频，且前景检测准确度优于同类算法。%To extract moving foreground from a video captured by a moving camera, dense optical flow or point trajectories are often introduced to handle the camera motion, but they make the moving foreground extraction very slow. To solve this problem, a simple and effective real-time algorithm for moving camera background sub-traction is proposed. Firstly, a superpixel-based region growing algorithm is proposed to preprocess the input im-age frames. Then, the camera motion is estimated in a block-based fashion with a background feature-point fil-tering method based on the relative flow. Finally, the background subtraction result is obtained via a verification process based on the accordance of the optical flow and the camera motion. Experimental results show that the proposed algorithm can process a 640×480 video in real-time. In addition, the foreground detection accuracy of the proposed algorithm outperforms other real-time moving foreground extraction methods.
Kwiatkowski, M; Alsdorf, M; Dehning, B; Vigano, W
2012-01-01
The aim of the Beam Loss Monitoring Dual Polarity (BLEDP) module under development at the European Organisation for Nuclear Research (CERN) is to measure and digitise with high precision the current produced by several types of beam loss detectors. The BLEDP module consists of eight analogue channels each with a fully differential integrator and an accompanying 16 bit ADC at the output of each analogue integrator. The on-board FPGA device controls the integral periods, instructs the ADC devices to perform measurements at the end of each period and collects the measurements. In the next stage it combines the number of charge and discharge cycles accounted in the last interval together with the cycle fractions observed using the ADC samples to produce a digitised high precision value of the charges collected. This paper describes briefly the principle of the fully differential integrator and focuses on the algorithm employed to process the digital data.
Yong, Bin; Ren, Liliang; Hong, Yang; Gourley, Jonathan; Tian, Yudong; Huffman, George J.; Chen, Xi; Wang, Weiguang; Wen, Yixin
2013-01-01
The TRMM Multi-satellite Precipitation Analysis (TMPA) system underwent a crucial upgrade in early 2009 to include a climatological calibration algorithm (CCA) to its realtime product 3B42RT, and this algorithm will continue to be applied in the future Global Precipitation Measurement era constellation precipitation products. In this study, efforts are focused on the comparison and validation of the Version 6 3B42RT estimates before and after the climatological calibration is applied. The evaluation is accomplished using independent rain gauge networks located within the high-latitude Laohahe basin and the low-latitude Mishui basin, both in China. The analyses indicate the CCA can effectively reduce the systematic errors over the low-latitude Mishui basin but misrepresent the intensity distribution pattern of medium-high rain rates. This behavior could adversely affect TMPA's hydrological applications, especially for extreme events (e.g., floods and landslides). Results also show that the CCA tends to perform slightly worse, in particular, during summer and winter, over the high-latitude Laohahe basin. This is possibly due to the simplified calibration-processing scheme in the CCA that directly applies the climatological calibrators developed within 40 degrees latitude to the latitude belts of 40 degrees N-50 degrees N. Caution should therefore be exercised when using the calibrated 3B42RT for heavy rainfall-related flood forecasting (or landslide warning) over high-latitude regions, as the employment of the smooth-fill scheme in the CCA bias correction could homogenize the varying rainstorm characteristics. Finally, this study highlights that accurate detection and estimation of snow at high latitudes is still a challenging task for the future development of satellite precipitation retrievals.
吴昊; 顾宗华
2013-01-01
虚拟化技术在服务器领域已经得到广泛应用,可以在一台服务器或服务器集群上同时运行几个不同的操作系统,诸多优点包括:故障隔离、高效利用资源、负载均衡、安全性等.常用的虚拟化系统如VMware、Virtual PC等采用全虚拟化技术,比较消耗资源,因此不适用于嵌入式领域的应用.而Xen采用半虚拟化技术,性能方面得到了很大提升,为虚拟化技术在嵌入式领域的应用创造了条件.由于嵌入式设备有着数据实时采集、现场控制、高危环境等特殊应用背景,嵌入式系统对实时性都有一定的要求.目前的虚拟化技术没有很好的方法来保障系统的实时性.本文在XEN虚拟化环境中设计并实现基于资源预留的实时调度算法,即在虚拟机监视器(Virtual Machine Monitor,VMM)层面实现常量带宽服务器(Constant Bandwidth Server,CBS)调度算法,用于有效调度实时和非实时的虚拟机子系统,并保障不同子系统之间的性能隔离.%Virtualization technology has found wide applications in the server application space.It enables running multiple different operating systems simultaneously on a single server or server cluster.Its many advantages include:fault isolation,high resource utilization,load balancing,security,etc.Popular virtualization systems like VMWare,Virtual PC use full virtualization technology with high resource consumption,hence they are not suitable for application in embedded systems.Xen adopts para-virtualization technology to improve performance,making it a good candidate for application in embedded systems.Embedded systems applications,such as real-time data collection,field control,safety-critical environment,have stringent requirements on real-time properties,but today's virtualization technology cannot make real-time guarantees.In this paper,we design and implement real-time scheduling algorithms based on resource reservation,i.e.,implement the resource reservation
Real-Time Watercolor for Animation
Thomas Luft; Oliver Deussen
2006-01-01
We present algorithms that allow for real-time rendering of 3D-scenes with a watercolor painting appearance. Our approach provides an appropriate simplification of the visual complexity, imitates characteristic natural effects of watercolor, and provides two essential painting techniques: the wet-on-wet and the wet-on-dry painting. We concentrate on efficient algorithms based on image space processing rather than on an exact simulation. This allows for the real-time rendering of 3D-scenes. During an animation a high frame-to-frame coherence can be achieved due to a stable segmentation scheme. Finally, we seamlessly integrate a smooth illumination into the watercolor renderings using information from the 3D-scene.
Monte Carlo study of real time dynamics
Alexandru, Andrei; Bedaque, Paulo F; Vartak, Sohan; Warrington, Neill C
2016-01-01
Monte Carlo studies involving real time dynamics are severely restricted by the sign problem that emerges from highly oscillatory phase of the path integral. In this letter, we present a new method to compute real time quantities on the lattice using the Schwinger-Keldysh formalism via Monte Carlo simulations. The key idea is to deform the path integration domain to a complex manifold where the phase oscillations are mild and the sign problem is manageable. We use the previously introduced "contraction algorithm" to create a Markov chain on this alternative manifold. We substantiate our approach by analyzing the quantum mechanical anharmonic oscillator. Our results are in agreement with the exact ones obtained by diagonalization of the Hamiltonian. The method we introduce is generic and in principle applicable to quantum field theory albeit very slow. We discuss some possible improvements that should speed up the algorithm.
Real-time optical information processing
Javidi, Bahram
1994-01-01
Real-Time Optical Information Processing covers the most recent developments in optical information processing, pattern recognition, neural computing, and materials for devices in optical computing. Intended for researchers and graduate students in signal and information processing with some elementary background in optics, the book provides both theoretical and practical information on the latest in information processing in all its aspects. Leading researchers in the field describe the significant signal processing algorithms architectures in optics as well as basic hardware concepts,
符利华; 张立臣
2011-01-01
This paper introduced the newest issue-Cyber-Physical Systems (CPS) and some basic contents of Cyber-Physical Systems. And then,it gave a heterogeneous distributed real-time task system model in the Cyber-Physical Systems. Based on this model and the primary-backup technology ,this paper proposed two fault-tolerant scheduling algorithms,which adapt to the heterogeneous distributed real-time environment of Cyber-Physical Systems:HDLMA (Heterogeneous Distributed Min Loading Algorithm) and H DLFA (Heterogeneous Distributed Loading Factor Algorithm). Finally,this paper analyzed their schedulability,load balancing,the influence of the granularity of tasks on load balancing as well as how scheduling threshold affects the schedulability.%介绍了Cyber-Physical Systems的基本内容,给出了基于Cyber-Physical Systems异构分布式中的实时任务系统模型.并在该模型下结合基/副版本备份技术提出了两种适应于Cyber-Physical Systems异构分布式实时环境的启发式容错调度算法:HDLMA算法和HDLFA算法.最后针对这两种算法,分析了算法可调度性,负载均衡性,任务粒度大小对负载均衡性的影响,以及调度闽值对算法可调度性的影响.
Real Time Collision Detection Using Depth Texturing Spheres
WANG Ji; ZHAI Zhengjun; CAI Xiaobin
2006-01-01
In this paper, we present a novel collision detection algorithm to real time detect the collisions of objects. We generate sphere textures of objects, and use programmable graphics hardware to mapping texture and check the depth of different objects to detect the collision. We have implemented the algorithm and compared it with CULLIDE. The result shows that our algorithm is more effective than CULLIDE and has fixed executive time to suit for real-time applications.
Near real-time stereo matching using geodesic diffusion.
De-Maeztu, Leonardo; Villanueva, Arantxa; Cabeza, Rafael
2012-02-01
Adaptive-weight algorithms currently represent the state of the art in local stereo matching. However, due to their computational requirements, these types of solutions are not suitable for real-time implementation. Here, we present a novel aggregation method inspired by the anisotropic diffusion technique used in image filtering. The proposed aggregation algorithm produces results similar to adaptive-weight solutions while reducing the computational requirements. Moreover, near real-time performance is demonstrated with a GPU implementation of the algorithm.
基于GPU的实时素描风格渲染算法%Real-time sketch style rendering algorithm based on GPU
高山晓; 吴献
2015-01-01
To simulate lines and shades in sketch style better, this paper presented an improved technique for rendering 3D meshes in the pencil drawing style. The algorithm divided the rendering process into three processes - contour drawing, texture drawing and tone adjustment. For contour drawing, this paper used multi-sampling to detect object contours and proposed chi-square distribution and trigonometric function to imitate the pencil line drawing. For texture drawing, this paper used the tangent and binormal of the model to generate integration directions. Then a pencil drawing texture was generated by using Liner Integral Convolution ( LIC) technology. As the result of the blend of multiple rendering may lead the tone to gray, this paper added the tone drawing before the final output. Through the Newton interpolation method to calculate the output curve, the final color distribution results were more like pencil drawing style. Experiments show that the work is more efficient and has a better performance. This algorithm can better simulate the hand-painted style lines and be applied to video game rendering.%为了更好地模拟素描画中线条的轻重变化和明暗变化，提出了一种改进的素描风格渲染算法。将渲染过程分为轮廓线绘制、纹理绘制和色调调整三个部分；在轮廓线染绘制过程中采用多重采样来辨识轮廓线，利用卡方分布和紊乱场来模拟生成素描化线条绘制；在纹理渲染绘制中，利用模型的切线和副法线生成多个方向场，通过对白噪声纹理的线性卷积( LIC)生成素描化纹理；通过牛顿插值法重新计算了输出曲线解决多重渲染混合后绘制效果偏灰问题。实验结果显示改进后素描风格渲染算法具有更高的渲染效率和更好的渲染效果。算法能够较好地实现素描风格的渲染效果，并可广泛适用于影视游戏开发中。
Mohammed H. Al-Jammas
2014-04-01
Full Text Available The video coding standards are being developed to s atisfy the requirements of applications for various purposes, better picture quality, higher co ding efficiency, and more error robustness. The new international video coding standard H.264 / AVC aims at having significant improvements in coding efficiency, and error robust ness in comparison with the previous standards such as MPEG-2, H261, H263,and H264. Vide o stream needs to be processed from several steps in order to encode and decode the vid eo such that it is compressed efficiently with available limited resources of hardware and softwar e. All advantages and disadvantages of available algorithms should be known to implement a codec to accomplish final requirement. The purpose of this project is to implement all bas ic building blocks of H.264 video encoder and decoder. The significance of the project is the inc lusion of all components required to encode and decode a video in MatLab .
Jorge Solis; Atsuo Takanishi
2010-01-01
-The aim of this paper is to create an interface for robot interaction.Specifically,musical performance parameters (i.e.vibrato expression) of the Waseda Flutist Robot No.4 Refined Ⅳ (WF-4RIV) are to be manipulated.This research focused on enabling the WF-4RIV to interact with human players (musicians) in a natural way.In this paper,as the first approach,a vision processing algorithm,which is able to track the 3D-orientation and position of a musical instrument,was developed.In particular,the robot acquires image data through two cameras attached to its head.Using color histogram matching and a particle filter,the position of the musician's hands on the instrument are tracked.Analysis of this data determines orientation and location of the instrument.These parameters are mapped to manipulate the musical expression of the WF4RIV,more specifically sound vibrato and volume values.The authors present preliminary experiments to determine if the robot may dynamically change musical paramenters while interacting with a human player (i.e.vibrato etc.).From the experimental results,they may confirm the feasibility of the interaction during the performance,although further research must be carried out to consider the physical constraints of the flutist robot.
Huang, Canhong; Lu, Xinghua; Jiang, Youen; Wang, Xiaochao; Qiao, Zhi; Fan, Wei
2017-02-20
FM-AM modulation of high-power lasers significantly affects laser performance. Therefore, precise measurement of the FM-AM modulation depth is necessary. The subsequent FM-AM modulation generated by group velocity dispersion when the laser pulse propagates through a fiber affects the measurement accuracy. In order to eliminate this effect, a waveform-acquisition module is proposed that converts a broad-spectrum pulse of 1053 nm to a narrow-spectrum pulse of 1550 nm, without affecting the waveform. In addition, a signal-processing algorithm based on the orthogonal matching pursuit method is implemented to remove the sampling noise from the waveform. In this way, the signal-to-noise ratio of the measurement can be readily improved. Both theoretical and experimental results indicate that the proposed FM-AM modulation detection system is effective and economical. It can measure the FM-AM modulation depth precisely, and therefore shows considerable promise for future applications in high-power lasers.
周世伟; 张平; 全炜; 徐志洋
2012-01-01
现有的NURBS曲线插补算法大多只关注合成加速度的平稳过渡,却忽略了各轴加速度是否超出电机的加减速能力.为了把弓高误差、各轴的速度及加速度同时限制在允许范围内,对现有限制合成加速度的自适应插补算法提出改进.算法主要包括两部分:预处理和实时插补.预处理首先对NRUBS曲线进行分段；接着在实时插补中设计了一个前瞻模块,对各分段曲线进行速度规划,使进给速度同时满足弓高误差和各轴加速度限制,并确定减速点.采用高性能处理器,使前瞻处理和插补计算同时进行,实现实时插补.最后通过MATLAB实例仿真,验证了算法的正确性和可行性.%Most of the exiting NURBS interpolation algorithm focus on the fluctuating of synthetical acceleration but ignore the individual axis acceleration. The approach proposed in this paper aims at restricting the chord error and axis acceleration in the permission range simultaneously. The proposed algorithm includes two main parts; pre-processing and real-time interpolation. Firstly, the NURBS curve is divided into some segments in the pre-processing part. And a look-ahead module is designed in the real-time interpolation , which conducts the feedrate profile of each segment, as the result of that, the feed rate is restricted by both of the chord error and the axis acceleration, and then the deceleration points are determined. With high performance processor, the look-ahead module and real-time interpolation can be practically conducted simultaneously. Finally, MATLAB simulations are performed to verify the correctness and feasibility of the proposed algorithm.
基于OpenCV的实时手势识别算法研究%Research of algorithm for real-time gesture recognition based on OpenCV
许艳旭; 张崎; 武霞
2013-01-01
文中介绍了一种易于实现的快速实时手势识别算法.研究借助计算机视觉库OpenCV和微软Visual Studi0 2008搭建开发平台,通过视频方式实时提取人的手势信息,进而经二值化、膨胀腐蚀、轮廓提取、区域分割等图像处理流程甄别出当前手势中张开的手指,识别手势特征,提取出人手所包含的特定信息,并最终将手势信息作为控制仪器设备的操作指令,控制相关设备仪器.%This article describes an easily achieved real-time gesture recognition algorithm. In this study, it sets up the development platform by means of computer vision library OpenCV and Microsoft Visual Studio 2008. Extracting gesture information through the real-time video, image binarization, expansion and corrosion, contour extraction, region segmentation and other process would be used to screen out the open fingers in the current gesture. Then characteristics recognition and information extracted would be operated to achieve the gesture information. Finally, it uses the gesture information to control equipment as the operating instructions.
Implementation of Real-time Crowds Simulation Algorithm Based on GPU%基于GPU的实时群体仿真算法实现
范晓晔; 田丰林; 陈戈
2014-01-01
群体仿真在虚拟现实、影视动画、计算机游戏等领域有着广泛的应用。大规模的群体仿真中每个个体都要同其感知范围内的其他个体相互作用，当实时更新所有个体的状态时，就会导致O( N2)计算量的问题。针对这一问题，实现了一种基于GPU(图形处理器)的BOIDS群体行为模拟算法，充分利用GPU并行计算的能力处理大规模群体运动的巨大计算量。该方法利用GPU的快速光栅化计算每个个体同其感知范围内的其他个体的相互作用力，通过像素颜色混合功能实现作用力的累加，利用GPU自动生成MipMap的能力计算所有个体的平均速度和平均位置。实验结果表明，该方法能够有效提高大规模群体运动的渲染速度。%Crowds simulation has a wide range of applications in the fields such as virtual reality,film animation,computer game and so on. In the simulation of massive crowds,each individual must interact with other individuals within the range of its perception. The upda-ting of all individuals' velocities and positions result in a O( N2 ) computation. Present a GPU based implementation of BOIDS flock al-gorithm to solve the problem mentioned before. The implementation takes full advantage of parallel computing of GPU to overcome the huge computational cost in massive crowds' animation. The approach mentioned in this paper makes full use of the fast rasterization capa-bility of GPU to compute the force between each individual and its neighbor,the pixel color blending capability to accumulate the force, generating the MipMap capability to get the average velocity and average position of all individuals. Experimental results indicate that this method can improve the speed and efficiency of rendering in the simulation of large-scale crowds.
Burnett, L; Basten, A; Hensley, W J
1986-01-10
Most computer algorithms used for comparing or aligning nucleotide sequences rely on the premise that the best way to extend a homology between the two sequences is to select a match rather than a mismatch. We have tested this assumption and found that it is not always valid.
Real time ray tracing of skeletal implicit surfaces
Rouiller, Olivier; Bærentzen, Jakob Andreas
Modeling and rendering in real time is usually done via rasterization of polygonal meshes. We present a method to model with skeletal implicit surfaces and an algorithm to ray trace these surfaces in real time in the GPU. Our skeletal representation of the surfaces allows to create smooth models...
Solder, Ulrich; Graefe, Volker
1991-03-01
An algorithm working on monocular gray-scale image sequences for object detection combined with a road tracker is presented. This algorithm appropriate for the real-time demands of an autonomous car driving with speeds over 40 km/h may be used for triggering obstacle avoidance maneuvers such as coming to a safe stop automatically in front of an obstacle or following another car. Moving and static objects have been detected in real-world experiments on various types of roads even under unfavorable weather conditions. . Morgenthaler and
H.264高清视频解码实时错误掩盖算法%Real-time Error Concealment Algorithm for H.264 High Definition Video Decoding
谢涛; 李志华; 黄轶伦
2011-01-01
针对IP网络丢包条件下的H.264高清视频实时解码问题,分析高清视频码流的特点,提出一种实时错误掩盖算法.该算法利用丢失片的边缘宏块信息,以垂直距离为权值加权平均预测得到错误宏块的运动矢量,进而完成错误掩盖.实验表明,与Joint模型中的错误掩盖算法相比,该算法提升了重建图像的主观质量和客观质量,计算复杂度较低,错误掩盖效果较好,适用于高清实时解码.%Aiming at real-time decode H.264 video on IP network with packet losses, an effective error concealment algonthm is proposed depending on the analysis of high definition video streams.By use of the edge macro-blocks information of the lost slice.the motion vector of corrupted macro-block is predicted, and the error concealment is completed.Experimental results show that.compared with the error concealment of Joint Model(JM), the proposed algorithm improves the objective quality and subjective quality of reconstructed images.The algorithm does not increase the complexity of the decoding, but achieves better recovery results.It is ideal for real-time decoding for high definition video.
Unified Modeling of Complex Real-Time Control Systems
Hai, He; Chi-Lan, Cai
2011-01-01
Complex real-time control system is a software dense and algorithms dense system, which needs modern software engineering techniques to design. UML is an object-oriented industrial standard modeling language, used more and more in real-time domain. This paper first analyses the advantages and problems of using UML for real-time control systems design. Then, it proposes an extension of UML-RT to support time-continuous subsystems modeling. So we can unify modeling of complex real-time control systems on UML-RT platform, from requirement analysis, model design, simulation, until generation code.
Evaluating real-time forecasts in real-time
D.J.C. van Dijk (Dick); Ph.H.B.F. Franses (Philip Hans); F. Ravazzolo (Francesco)
2007-01-01
textabstractThe accuracy of real-time forecasts of macroeconomic variables that are subject to revisions may crucially depend on the choice of data used to compare the forecasts against. We put forward a flexible time-varying parameter regression framework to obtain early estimates of the final valu
Towards Real-Time Argumentation
Vicente JULIÁN
2016-07-01
Full Text Available In this paper, we deal with the problem of real-time coordination with the more general approach of reaching real-time agreements in MAS. Concretely, this work proposes a real-time argumentation framework in an attempt to provide agents with the ability of engaging in argumentative dialogues and come with a solution for their underlying agreement process within a bounded period of time. The framework has been implemented and evaluated in the domain of a customer support application. Concretely, we consider a society of agents that act on behalf of a group of technicians that must solve problems in a Technology Management Centre (TMC within a bounded time. This centre controls every process implicated in the provision of technological and customer support services to private or public organisations by means of a call centre. The contract signed between the TCM and the customer establishes penalties if the specified time is exceeded.
罗钢
2014-01-01
计算机并行技术和通信技术的快速发展，使得大规模电力系统暂态实时仿真成为可能。介绍电磁暂态仿真和机电暂态仿真所采用的模型和计算方法以及各自并行算法所取得的研究进展和实用效果，讨论了基于网络分割和集群计算机系统的粗粒度并行算法，分析表明该类算法具有较高的并行效率以及较好的发展潜力。%Rapid development of computer parallel technology and communication technology makes real-time simulation of large-scale power system transient possible. Models and calculation methods for electromagnetic transient and electrome-chanical transient were introduced as well as research development and practical effect of each parallel algorithm was presen-ted. Coarsness parallel algorithm based on network partitioning and trunking computer system was discussed. Analysis indi-cated that this algorithm was provided with higher parallel effeciency and better development potential.
Real Time Route for Dynamic Road Congestions
A. M. Riad
2012-05-01
Full Text Available Minimizing service delivery and travel time during rush hours downtown is strategic target for several organizations, especially the emergency organizations. This paper presents an On-line and Real-time Dynamic Route System (ORDRS which benefits from the advantages and integration between information system and communications technology. It utilizes Global Positioning System (GPS, Geographical Information Systems (GIS, and Global System for Mobile communications (GSM; for producing the real time routes for vehicles. GPS-Tracker is the main input device for ORDRS. It is fixated in a vehicle, sends vehicle's movement data (Geo-info to the control center wirelessly through either Short Message Service (SMS or General Packet Radio Service (GPRS. Geo-info includes time, date, longitude, latitude, speed, and etc., these data is classified over time during weekdays into interval time slices, each slice is 30 minutes. Speeds are treated by GIS tools to determine historical and real time speeds for each street segment in the road network which is being used for calculating time impedance (cost matrix for each street segment dynamically. ORDRS uses a cost matrix of the current time slice for determining the best route to each vehicle in duty attached. Several algorithms was used to calculate the shortest route, a comparison between Dijekstra and Yen algorithms was studied.
Real-time Interactive Tree Animation.
Quigley, Ed; Yu, Yue; Huang, Jingwei; Lin, Winnie; Fedkiw, Ronald
2017-01-30
We present a novel method for posing and animating botanical tree models interactively in real time. Unlike other state of the art methods which tend to produce trees that are overly flexible, bending and deforming as if they were underwater plants, our approach allows for arbitrarily high stiffness while still maintaining real-time frame rates without spurious artifacts, even on quite large trees with over ten thousand branches. This is accomplished by using an articulated rigid body model with as-stiff-as-desired rotational springs in conjunction with our newly proposed simulation technique, which is motivated both by position based dynamics and the typical O(N) algorithms for articulated rigid bodies. The efficiency of our algorithm allows us to pose and animate trees with millions of branches or alternatively simulate a small forest comprised of many highly detailed trees. Even using only a single CPU core, we can simulate ten thousand branches in real time while still maintaining quite crisp user interactivity. This has allowed us to incorporate our framework into a commodity game engine to run interactively even on a low-budget tablet. We show that our method is amenable to the incorporation of a large variety of desirable effects such as wind, leaves, fictitious forces, collisions, fracture, etc.
Real-time numerical simulation of the Carnot cycle
Hurkala, J.; Gall, M.; Kutner, R.; Maciejczyk, M.
2005-09-01
We developed a highly interactive, multi-windows Java applet which made it possible to simulate and visualize within any platform and internet the Carnot cycle (or engine) in a real-time computer experiment. We extended our previous model and algorithm (Galant et al 2003 Heat Transfer, Newton's Law of Cooling and the Law of Entropy Increase Simulated by the Real-Time Computer Experiments in Java (Lecture Notes in Computer Science vol 2657) pp 45-53, Gall and Kutner 2005 Molecular mechanisms of heat transfer: Debye relaxation versus power-law Physica A 352 347-78) to simulate not only the heat flow but also the macroscopic movement of the piston. Since in reality it is impossible to construct a reversible Carnot engine, the question arises whether it is possible to simulate it at least in a numerical experiment? The positive answer to this question which we found is related to our model and algorithm which make it possible to omit the many-body problem arising when many gas particles simultaneously interact with the mobile piston. As usual, the considerations of phenomenological thermodynamics began with a study of the basic properties of heat engines, hence our approach, besides intrinsic physical significance, is also important from the educational, technological and even environmental points of view. .
A real-time transaction service for grid computing
Tang Feilong; Li Minglu; Joshua Huang Zhexue; Frank Tong; Cao Jian
2005-01-01
A real-time transaction service aims at ensuring the consistency of real-time and transactional Grid applications. This paper proposes an efficient real-time transaction service (RTTS). It provides abilities to discover qualified services, I.e., participants, to execute specified sub-transactions, coordinate real-time Grid transactions, calculate deadline and assign priority for scheduling concurrent transactions. The service discovery adopts the two-level registry mechanismto adapt to transient Grid services. The coordination algorithm invokes multiplefunctional alternative services for each sub-transaction so that it remarkablyimproves the successful ratio of real-time transactions. The experiment result shows that the RTTS can well coordinate real-time transactions for Grid service environment and shield users from the complex process.
System Equivalent for Real Time Digital Simulator
Lin, Xi
2011-07-01
The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.
Haering, Ed
2014-01-01
This presentation will provide general information about sonic boom mitigation technology to the public in order to supply information to potential partners and licensees. The technology is a combination of flight data, atmospheric data and terrain information implemented into a control room real time display for flight planning. This research is currently being performed and as such, any results and conclusions are ongoing.
Real Time Conference 2016 Overview
Luchetta, Adriano
2017-06-01
This is a special issue of the IEEE Transactions on Nuclear Science containing papers from the invited, oral, and poster presentation of the 20th Real Time Conference (RT2016). The conference was held June 6-10, 2016, at Centro Congressi Padova “A. Luciani,” Padova, Italy, and was organized by Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA) and the Istituto Nazionale di Fisica Nucleare. The Real Time Conference is multidisciplinary and focuses on the latest developments in real-time techniques in high-energy physics, nuclear physics, astrophysics and astroparticle physics, nuclear fusion, medical physics, space instrumentation, nuclear power instrumentation, general radiation instrumentation, and real-time security and safety. Taking place every second year, it is sponsored by the Computer Application in Nuclear and Plasma Sciences technical committee of the IEEE Nuclear and Plasma Sciences Society. RT2016 attracted more than 240 registrants, with a large proportion of young researchers and engineers. It had an attendance of 67 students from many countries.
Real time automatic scene classification
Israël, Menno; Broek, van den Egon L.; Putten, van der Peter; Uyl, den Marten J.; Verbrugge, R.; Taatgen, N.; Schomaker, L.
2004-01-01
This work has been done as part of the EU VICAR (IST) project and the EU SCOFI project (IAP). The aim of the first project was to develop a real time video indexing classification annotation and retrieval system. For our systems, we have adapted the approach of Picard and Minka [3], who categorized
Decentralized Real-Time Scheduling
1990-08-01
917-932, August, 1987. [ Daniels 86] D. C. Daniels and H. F. Wedde. Real-Time Performance of a Completely Distributed Operating System. In Proceedings...imnmediate execuoon The schedule c.-eated by the SeltctPhaseProcfj procedure is an ordere-d lis t of mocl -phnise pairs, each placed according to the
Real time automatic scene classification
Verbrugge, R.; Israël, Menno; Taatgen, N.; van den Broek, Egon; van der Putten, Peter; Schomaker, L.; den Uyl, Marten J.
2004-01-01
This work has been done as part of the EU VICAR (IST) project and the EU SCOFI project (IAP). The aim of the first project was to develop a real time video indexing classification annotation and retrieval system. For our systems, we have adapted the approach of Picard and Minka [3], who categorized
Validation of the Eclipse AAA algorithm at extended SSD.
Hussain, Amjad; Villarreal-Barajas, Eduardo; Brown, Derek; Dunscombe, Peter
2010-06-08
The accuracy of dose calculations at extended SSD is of significant importance in the dosimetric planning of total body irradiation (TBI). In a first step toward the implementation of electronic, multi-leaf collimator compensation for dose inhomogeneities and surface contour in TBI, we have evaluated the ability of the Eclipse AAA to accurately predict dose distributions in water at extended SSD. For this purpose, we use the Eclipse AAA algorithm, commissioned with machine-specific beam data for a 6 MV photon beam, at standard SSD (100 cm). The model was then used for dose distribution calculations at extended SSD (179.5 cm). Two sets of measurements were acquired for a 6 MV beam (from a Varian linear accelerator) in a water tank at extended SSD: i) open beam for 5 x 5, 10 x 10, 20 x 20 and 40 x 40 cm2 field sizes (defined at 179.5 cm SSD), and ii) identical field sizes but with a 1.3 cm thick acrylic spoiler placed 10 cm above the water surface. Dose profiles were acquired at 5 cm, 10 cm and 20 cm depths. Dose distributions for the two setups were calculated using the AAA algorithm in Eclipse. Confidence limits for comparisons between measured and calculated absolute depth dose curves and normalized dose profiles were determined as suggested by Venselaar et al. The confidence limits were within 2% and 2 mm for both setups. Extended SSD calculations were also performed using Eclipse AAA, commissioned with Varian Golden beam data at standard SSD. No significant difference between the custom commissioned and Golden Eclipse AAA was observed. In conclusion, Eclipse AAA commissioned at standard SSD can be used to accurately predict dose distributions in water at extended SSD for 6 MV open beams.
High performance reconfigurable hardware system for real-time image processing
无
2005-01-01
A novel reconfigurable hardware system which uses both multi-DSP and FPGA to attain high performance and real-time image processing are presented. The system structure and working principle of mainly processing multi-DSP board, extended multi-DSP board are analysed. The outstanding advantage is that the communication among different board components of this system is supported by high speed link ports & serial ports for increasing the system performance and computational power. Then the implementation of embedded real-time operating systems (RTOS) by us is discussed in detail. In this system, we adopt two kinds of parallel structures controlled by RTOS for parallel processing of algorithms. The experimental results show that exploitive period of the system is short, and maintenance convenient.Thus it is suitable for real-time image processing and can get satisfactory effect of image recognition.
冯延蓬; 仵博; 郑红燕
2012-01-01
针对异构无线传感器网络节点性能存在差异和易受环境影响的特点,提出一种基于部分可观察Markov决策过程(partially observable markov decision process,POMDP)的实时休眠调度算法,使用状态转移函数和观察函数表示系统完成用户请求任务中存在的环境噪声和传输冲突等不确定性,使用回报函数表示采用不同调度策略对异构网络感知准确度和能量消耗的影响,采用基于当前信念点的在线求解算法求取最优策略.仿真结果表明:该算法能够平衡数据准确性与能量消耗,延长网络生存时间.%To handle the issues of node performance heterogeneity and environmental sensitivity with heterogeneous wireless sensor networks,a partially observable markov decision process (POMDP) based real-time sleeping scheduling algorithm was proposed. The algorithm used state transition function and observation function to represent the uncertainty in the network performance caused by environmental noise and transmission conflicts, and used reward function to represent the impacts of different scheduling strategies on the sensing accuracy and energy consumption. It solved for the optimal scheduling policy using belief point based online algorithm. Simulation results show that the algorithm can achieve a good tradeoff between data accuracy and energy consumption , and can prolong the network lifetime.
姜艳; 曾学文; 孙鹏; 朱小勇
2012-01-01
In order to raise the memory management efficiency in real-time embedded multimedia systems, a fuzzy threshold coalescence memory algorithm based on TLSF (Two-Level Segregate Fit) is proposed. This algorithm employs fuzzy rules combined with the probability of free memory regions and statistics of free memory blocks in every region to obtain the coalescence coefficient, which is compared with dynamic threshold adjusted by memory fragmentation to decide whether the coalescence needs to be postponed. Experimental results show that the performance of this algorithm is similar to that of TLSF when the allocated memory size is random, but allocation and release efficiencies are increased by 12. 6% and 9.5% , respectively, in a real video on the demand system, by adopting this algorithm in an embedded system.%为了提高实时嵌入式多媒体系统动态内存分配的效率,提出一种基于两级离散列表(Two-Level Segregate Fit,TLSF)的模糊阈值合并算法.根据内存区间的使用概率和空闲块数统计,运用模糊规则计算合并系数,并与由碎片率决定的动态阈值相比较,决定是否推迟合并.实验结果表明,该算法在内存大小随机分配时与TLSF算法的性能相当；在实际的视频点播系统应用中,分配和释放效率分别提高了12.6％和9.5％.
夏平; 周兴社
2013-01-01
The paper solved the problem that current popular safeguard scheduling algorithm cannot achieve the safeguard function under the environment of software and hardware failure. It built a new hierarchical real-time scheduling model which describes the safety requirement of safety-critical real-time application from two aspects including function component and safe partition, and designed a three-level safeguard scheduler framework Based on the model and framework, the paper proposed a new hierarchical safeguard scheduling algorithm (HSS) which achieves spacial separation effect by distributing function components with different critical degrees to different physical processor clusters,and attains temporal separation effect by activating various partitions running on the same processor in a fixed cycle. Empirical investigations show that the improvements in the safeguard performance and the endurance to different application loads can be achieved by choosing HSS than other similar algorithms.%针对现有防危调度算法在软硬件失效情况下防危能力不足的问题,具体进行了以下工作:构建了一种分层防危实时调度模型,该模型从功能组件和安全分区两方面描述了安全关键实时应用的防危性需求,并给出一种基于分层调度思想的三级防危调度器框架.以该模型和框架为基础,提出了一种新的分层防危调度算法(HSS),该算法对安全关键实时应用中不同关键度的功能组件采用空间隔离机制,对同一功能组件内的不同分区采用时间隔离机制,兼顾实现了时空隔离的防危效果.仿真实验结果表明,HSS算法与其他同类算法相比,在防危效果和应用负载承受能力方面具有较好的表现.
张贝贝; 武奇生
2011-01-01
违章停车是高速公路交通事故的重要诱因,因此迅速、有效地检测出违章车辆是高速公路交通管理与控制的重点。提出一种基于视频的高速公路车辆违章停车实时检测算法,在分析了基于视频的违章停车检测系统的组成和视频检测的优点的基础上,用背景差分算法和OSTU阈值相结合的方法,对所采集的某路段视频,进行车辆违章停车判断。实验表明,该方法效果良好。%Illegal parking of vehicles is an important incentive for highway incidents.Expedient and reliable illegal vehicles detection is a top priority of expressway traffic management and control.This paper presents a real-time highway vehicle parking detection algorithm based on video.First of all,the video-based detection system consists of illegal parking and the advantages of video detection are analyzed;then background subtraction algorithm and OSTU threshold method are combined to judge whether the vehicles is parking illegally.Experimental results show that the method has good results.
王凯; 于鸿洋; 张萍
2012-01-01
着眼于更宽泛和更便捷的应用需要,提出了基于AdaBoost算法和光流匹配的实时手势识别方案.只需连接到计算机的摄像头读取二维手势视频片段就能对手势作为较为准确的识别.其中,采用AdaBoost算法遍历图像,完成静态手势的识别工作;在动态手势的识别过程中,运用了光流法结合模板匹配的方法.整个系统对静态和动态手势的识别均具有较强的鲁棒性.%Focusing on more general and more convenient application, a novel real-time gesture recognition method based on AdaBoost algorithm and optical flow matching was put forward. In detail, the AdaBoost algorithm was used to traverse the whole image for the recognition of static gestures. As to the dynamic gestures, the method combining optical flow with template matching was utilized. The whole system has strong robustness in the recognition of both static and dynamic gestures.
Radiation damping in real time.
Mendes, A C; Takakura, F I
2001-11-01
We study the nonequilibrium dynamics of a charge interacting with its own radiation, which originates the radiation damping. The real-time equation of motion for the charge and the associated Langevin equation is found in classical limit. The equation of motion for the charge allows one to obtain the frequency-dependent coefficient of friction. In the lowest order we find that although the coefficient of static friction vanishes, there is dynamical dissipation represented by a non-Markovian dissipative kernel.
An Extended Clustering Algorithm for Statistical Language Models
Ueberla, J P
1994-01-01
Statistical language models frequently suffer from a lack of training data. This problem can be alleviated by clustering, because it reduces the number of free parameters that need to be trained. However, clustered models have the following drawback: if there is ``enough'' data to train an unclustered model, then the clustered variant may perform worse. On currently used language modeling corpora, e.g. the Wall Street Journal corpus, how do the performances of a clustered and an unclustered model compare? While trying to address this question, we develop the following two ideas. First, to get a clustering algorithm with potentially high performance, an existing algorithm is extended to deal with higher order N-grams. Second, to make it possible to cluster large amounts of training data more efficiently, a heuristic to speed up the algorithm is presented. The resulting clustering algorithm can be used to cluster trigrams on the Wall Street Journal corpus and the language models it produces can compete with exi...
An efficient real time superresolution ASIC system
Reddy, Dikpal; Yue, Zhanfeng; Topiwala, Pankaj
2008-04-01
Superresolution of images is an important step in many applications like target recognition where the input images are often grainy and of low quality due to bandwidth constraints. In this paper, we present a real-time superresolution application implemented in ASIC/FPGA hardware, and capable of 30 fps of superresolution by 16X in total pixels. Consecutive frames from the video sequence are grouped and the registered values between them are used to fill the pixels in the higher resolution image. The registration between consecutive frames is evaluated using the algorithm proposed by Schaum et al. The pixels are filled by averaging a fixed number of frames associated with the smallest error distances. The number of frames (the number of nearest neighbors) is a user defined parameter whereas the weights in the averaging process are decided by inverting the corresponding smallest error distances. Wiener filter is used to post process the image. Different input parameters, such as size of input image, enlarging factor and the number of nearest neighbors, can be tuned conveniently by the user. We use a maximum word size of 32 bits to implement the algorithm in Matlab Simulink as well as the hardware, which gives us a fine balance between the number of bits and performance. The algorithm performs with real time speed with very impressive superresolution results.
Santhi Baskaran
2010-12-01
Full Text Available Energy consumption is a critical design issue in real-time systems, especially in battery- operated systems. Maintaining high performance, while extending the battery life between charges is an interesting challenge for system designers. Dynamic Voltage Scaling (DVS allows a processor to dynamically change speed and voltage at run time, thereby saving energy by spreading run cycles into idle time.Knowing when to use full power and when not, requires the cooperation of the operating system scheduler. Usually, higher processor voltage and frequency leads to higher system throughput whileenergy reduction can be obtained using lower voltage and frequency. Instead of lowering processorvoltage and frequency as much as possible, energy efficient real-time scheduling adjusts voltage andfrequency according to some optimization criteria, such as low energy consumption or high throughput,while it meets the timing constraints of the real-time tasks. As the quantity and functional complexity ofbattery powered portable devices continues to raise, energy efficient design of such devices has becomeincreasingly important. Many real-time scheduling algorithms have been developed recently to reduceenergy consumption in the portable devices that use DVS capable processors. Extensive power awarescheduling techniques have been published for energy reduction, but most of them have been focusedsolely on reducing the processor energy consumption. While the processor is one of the major powerhungry units in the system, other peripherals such as network interface card, memory banks, disks alsoconsume significant amount of power. Dynamic Power Down (DPD technique is used to reduce energyconsumption by shutting down the processing unit and peripheral devices, when the system is idle. Threealgorithms namely Red Tasks Only (RTO, Blue When Possible (BWP and Red as Late as Possible (RLPare proposed in the literature to schedule the real-time tasks in Weakly-hard real-time
Herlin, T.; Brighton, A.; Biereichel, P.
The VLT Real-Time Display (RTD) software was developed in order to support image display in real-time, providing a tool for users to display video like images from a camera or detector as fast as possible on an X-Server. The RTD software is implemented as a package providing a Tcl/Tk image widget written in C++ and an independent image handling library and can be used as a building block, adding display capabilities to dedicated VLT control applications. The RTD widget provides basic image display functionality like: panning, zooming, color scaling, colormaps, intensity changes, pixel query, overlaying of line graphics. A large set of assisting widgets, e.g., colorbar, zoom window, spectrum plot are provided to enable the building of image applications. The support for real-time is provided by an RTD image event mechanism used for camera or detector subsystems to pass images to the RTD widget. Image data are passed efficiently via shared memory. This paper describes the architecture of the RTD software and summarizes the features provided by RTD.
Fault-Tolerant Scheduling for Real-Time Embedded Control Systems
Chun-Hua Yang; Geert Deconinck; Wei-Hua Gui
2004-01-01
With the increasing complexity of industrial application, an embedded control system (ECS) requires processing a number of hard real-time tasks and needs fault-tolerance to assure high reliability. Considering the characteristics of real-time tasks in ECS, an integrated algorithm is proposed to schedule real-time tasks and to guarantee that all real-time tasks are completed before their deadlines even in the presence of faults. Based on the nonpreemptive critical-section protocol (NCSP), this paper analyzes the blocking time introduced by resource conflicts of relevancy tasks in fault-tolerant multiprocessor systems. An extended schedulability condition is presented to check the assignment feasibility of a given task to a processor. A primary/backup approach and on-line replacement of failed processors are used to tolerate processor failures. The analysis reveals that the integrated algorithm bounds the blocking time, requires limited overhead on the number of processors, and still assures good processor utilization. This is also demonstrated by simulation results. Both analysis and simulation show the effectiveness of the proposed algorithm in ECS.
Real-time image and video processing
Kehtarnavaz, Nasser
2006-01-01
This book presents an overview of the guidelines and strategies for transitioning an image or video processing algorithm from a research environment into a real-time constrained environment. Such guidelines and strategies are scattered in the literature of various disciplines including image processing, computer engineering, and software engineering, and thus have not previously appeared in one place. By bringing these strategies into one place, the book is intended to serve the greater community of researchers, practicing engineers, industrial professionals, who are interested in taking an im
CUDA-based real time surgery simulation.
Liu, Youquan; De, Suvranu
2008-01-01
In this paper we present a general software platform that enables real time surgery simulation on the newly available compute unified device architecture (CUDA)from NVIDIA. CUDA-enabled GPUs harness the power of 128 processors which allow data parallel computations. Compared to the previous GPGPU, it is significantly more flexible with a C language interface. We report implementation of both collision detection and consequent deformation computation algorithms. Our test results indicate that the CUDA enables a twenty times speedup for collision detection and about fifteen times speedup for deformation computation on an Intel Core 2 Quad 2.66 GHz machine with GeForce 8800 GTX.
Systems Analyze Water Quality in Real Time
2010-01-01
A water analyzer developed under Small Business Innovation Research (SBIR) contracts with Kennedy Space Center now monitors treatment processes at water and wastewater facilities around the world. Originally designed to provide real-time detection of nutrient levels in hydroponic solutions for growing plants in space, the ChemScan analyzer, produced by ASA Analytics Inc., of Waukesha, Wisconsin, utilizes spectrometry and chemometric algorithms to automatically analyze multiple parameters in the water treatment process with little need for maintenance, calibration, or operator intervention. The company has experienced a compound annual growth rate of 40 percent over its 15-year history as a direct result of the technology's success.
Multiple extended target tracking algorithm based on Gaussian surface matrix
Jinlong Yang; Peng Li; Zhihua Li; Le Yang
2016-01-01
In this paper, we consider the problem of irregular shapes tracking for multiple extended targets by introducing the Gaussian surface matrix (GSM) into the framework of the random finite set (RFS) theory. The Gaussian surface function is constructed first by the measurements, and it is used to define the GSM via a mapping function. We then integrate the GSM with the probability hypothesis density (PHD) filter, the Bayesian recursion formulas of GSM-PHD are derived and the Gaussian mixture implementation is employed to obtain the closed-form solutions. Moreover, the estimated shapes are designed to guide the measurement set sub-partition, which can cope with the problem of the spatialy close target tracking. Simulation results show that the proposed algorithm can effectively estimate irregular target shapes and exhibit good robustness in cross extended target tracking.
An improved real-time background extraction algorithm based on Jung＇s method%基于改进Jung方法的实时背景提取算法
张挺; 赵向东; 李文军; 柴智
2012-01-01
结合帧间差分信息和Jung背景提取算法，提出了一种改进的用于运动目标检测的实时背景提取算法。该算法利用视频连续图像帧之间的差异信息加速背景更新过程，提取的背景图像能够快速适应背景中物体的变化，同时保留了基本Jung背景提取方法结构简单、运算速度快的特点．在PETS2001数据集上对本算法进行了有效性验证，实验结果表明。该算法可以实时准确地提取背景图像。%By eombining the Jung＇s background extraction algorithm and difference infonnation between the adjacent frames, an improved background extraction method is proposed in this paper. In order to accelerate the method, the difference information between the adjacent frames is employed. The background image extracted by the proposed method can adapt the change of the image sequence quickly, preserving the advantages of Jung＇s algorithm at the same time. The validity of the proposed algorithm is demonstrated through the PETS2001 data sets The experiment results show that the background image can be real-time extracted accurately.
段磊; 唐常杰; 左劫; 彭京; 刘婷婷; 苟驰
2011-01-01
用户在互联网发布信息的自由性对Web信息内容过滤提出新的挑战.为此,给出一种自学习的两级内容过滤算法SAFE (self-study algorithm of filtering Chinese text content).SAFE以数据流的方式处理文本,并根据Apriori性质,在不依赖词典的情况下,通过挖掘关键字和关键词实现对文档的两级内容过滤.利用真实世界Web文档验证了SAFE的有效性,实验表明对给定的主题进行文本内容过滤,SAFE的查全率达到93.75%以上,查准率达到100%,执行时间能够满足Web应用的实时性要求.%The publishing freedom of users on Internet poses new challenges in Web content filtering. This paper presents a self-study algorithm, called SAFE (self-study algorithm of filtering Chinese text content), for Chinese content filtering through two layers. It processes texts in the form of data stream. Based on Apriori property, SAFE filters Chinese text content through two layers by mining key characters and keywords without manual dictionary. The performance research of SAFE on the real-world data shows that for the given theme, the recall of SAFE is greater than 93.75% and the precision is 100%. The runtime of SAFE satisfies the real-time requirement of Web applications.
敬思远; 余堃; 钟毅
2011-01-01
充分考虑当前CMOS多核嵌入式处理器片上仅提供全局动态电压缩放(DVS)支持以及亚纳米时代后CMOS处理器泄露功耗不可忽视的现状,提出一种新的多核嵌入式环境中的硬实时任务感功调度算法GRR&CS.算法通过基于贪心法的静态任务划分,基于全局资源回收利用和任务迁移的动态负载均衡,以及动态核缩放三个步骤实现整体能耗的降低,并同时保证实时任务的可调度性约束.实验表明,提出的算法相比较现有算法多节省14.8％～41.2％的能耗.%Taking full consideration of that CMOS multi-core embedded processor only provides global Dynamic Voltage Scaling (DVS) and its power leakage is serious, this paper proposed a new power-aware scheduling algorithm GRR&CS for hard real-time tasks in multi-core embedded environment. The power saving was achieved by three steps, including greedy-based static tasks partition, global resource reclamation based dynamic load balance and dynamic core scaling. The algorithm also keeps the schedulability of tasks. The experimental results show that the proposed algorithm saves more about 14. 8% -41.2% energy than other existing works.
李娜; 侯义斌; 黄樟钦
2012-01-01
实时跌倒检测能为老年人和特别护理人员提供及时的帮助.根据人体的运动学特征,提出一种基于三轴加速度传感器的人体跌倒行为的实时检测算法.该算法通过提取运动时的超重强度、持续失重时间、倾斜角度、静止时间为特征值,在Android智能手机上使用决策树进行实时处理.该算法对传感器的放置方位无要求,选取日常动作和与跌倒加速度特征相似的动作进行测试,该算法的平均响应时间小于6秒,平均准确率达到92％,证明了该算法的有效性.%The real-time falling detection can provide old people timely alert and call for help. This paper introduces such an algorithm based on single triaxial accelerometer according to kinematic characteristics of human. We abstract value of overweight, continuous weightless time, tilting angle, still time as features, and implement a decision tree classifier running on an Android smartphone. The algorithm does not require fixing the orientation of sensor. We selected data from daily activities and a set of falling activities with similar acceleration feature for test. The results are that average response-time of the algorithm is less than 6 seconds and average accuracy is 92% , which shows its effectiveness.
Real-time Algorithm for Detection of Human State With Triaxial Accelerometer%基于三轴加速度信号的实时人体状态识别算法
李娜; 侯义斌; 黄樟钦; 韩广利; 张会兵
2012-01-01
Adapting to the limited resource of mobile device, a human state recognition algorithm based on Kalman filter was proposed, which could identify dynamic, static and state transition in real time. The Bluetooth module with a triaxial accelerometer was placed on the chest of body to collect three- dimensional acceleration data. The characteristic of human activity was associated with the features of the accelerometer signal, so the function of change of the signal vector magnitude (SVM) was processed by Kalman filter to identify human state. Experiment results show that the algorithm achieves high accuracy in identification of postural transition, meanwhile, the algorithm has displayed better performance with little overhead on the smartphone.%针对移动终端设备的硬件局限性,研究了一种基于卡尔曼滤波的非特定人体状态识别算法,实时判断人体的运动、静止、状态转换情况.将装有三轴加速度传感器的蓝牙模块放置在人体的胸部,获得运动时的三维加速度信号.结合人体运动状态的特征和加速度信号变化的相关性,采用信号矢量幅值变化量的函数进行卡尔曼滤波,对人体状态进行判断.实验结果表明,该算法在运算和存储能力有限的移动设备上取得了较好的性能.
王立炜; 廖延娜
2014-01-01
为了解决大规模会议中的混音噪声问题，提出语音短时累积能量的概念，并据此设计基于动态竞争模式的实时多媒体会议混音算法。该算法依据会议所有成员的语音短时累积能量，通过动态竞争、自我淘汰、强制淘汰三个过程，实时从会议所有成员中选择当前的发言者，并进行混音。仿真结果显示，该算法可解决大规模会议中混音质量与会议人数成反比的问题。%In order to solve the problem of mixing noise in large scale multimedia conference,a concept of short-term cumulative energy of speech signal is put forward,and a real-time audio mixing algorithm based on dynamic competition is given in this paper.In this algorithm,three processes:dynamic competition,self-obsolescing and forcible obsolescing are gone through ac-cording to short-term cumulative energy of speech signal which come from each member of the conference.Current spokesmen are selected,and their speech signals are mixed as output.Simu-lation results show that this algorithm can solve the problem that the audio mixing quality has an inverse relationship with membership of large scale multimedia conference.
GPEC, a real-time capable Tokamak equilibrium code
Rampp, Markus; Fischer, Rainer
2015-01-01
A new parallel equilibrium reconstruction code for tokamak plasmas is presented. GPEC allows to compute equilibrium flux distributions sufficiently accurate to derive parameters for plasma control within 1 ms of runtime which enables real-time applications at the ASDEX Upgrade experiment (AUG) and other machines with a control cycle of at least this size. The underlying algorithms are based on the well-established offline-analysis code CLISTE, following the classical concept of iteratively solving the Grad-Shafranov equation and feeding in diagnostic signals from the experiment. The new code adopts a hybrid parallelization scheme for computing the equilibrium flux distribution and extends the fast, shared-memory-parallel Poisson solver which we have described previously by a distributed computation of the individual Poisson problems corresponding to different basis functions. The code is based entirely on open-source software components and runs on standard server hardware and software environments. The real-...
毛琳; 曾庆超; 张静
2016-01-01
针对移动机器人近场声源定位中，需要实时获取声源目标与麦克风阵列中心相对位置和角度的问题，提出一种基于视频定位的室内声源位置测量算法，实时地为麦克风阵列提供初始化参数，为移动机器人快速建立室内近场声源环境认知实现辅助功能。该方法利用A4纸打印的位置定位板，通过摄像头采集视频数据，逐帧寻找角点后搜索定位板中心点和顶点，以此计算出麦克风阵列到声源的实际距离和方位角度。经仿真实验分析，该算法能够在室内环境中实时快速地测量声源目标位置，为机器人后续语音定位、识别与跟踪提供辅助与校准功能，具有较强的工程实用价值。%For obtaining the relative position and direction angle between sound source and the center of microphone array in real-time, the paper proposes an indoor video sound-source-localization measurement algorithm, in order to provide the initializing parameters for the micro-phone array so that offers the ability to realize the near field environment for a moving robot. This method uses the positioning plate which is printed on A4 paper, captures video -data through camera and searches the center point and the vertex points of the positioning plate frame by frame. According to the specified points, the actual distance and the direction angle of the microphone array to the sound sources have been derived. The simulation experiments show that this algorithm can measure source position indoor in real time, providing the auxiliary and cali-bration function for the subsequent voice location, identification and tracking and having a strong engineering practical value.
Low cost real time interactive analysis system
Stetina, F.
1988-01-01
Efforts continue to develop a low cost real time interactive analysis system for the reception of satellite data. A multi-purpose ingest hardware software frame formatter was demonstrated for GOES and TIROS data and work is proceeding on extending the capability to receive GMS data. A similar system was proposed as an archival and analysis system for use with INSAT data and studies are underway to modify the system to receive the planned SeaWiFS (ocean color) data. This system was proposed as the core of a number of international programs in support of U.S. AID activities. Systems delivered or nearing final testing are listed.
Real-time feedback from iterative electronic structure calculations
Vaucher, Alain C; Reiher, Markus
2015-01-01
Real-time feedback from iterative electronic structure calculations requires to mediate between the inherently unpredictable execution times of the iterative algorithm employed and the necessity to provide data in fixed and short time intervals for real-time rendering. We introduce the concept of a mediator as a component able to deal with infrequent and unpredictable reference data to generate reliable feedback. In the context of real-time quantum chemistry, the mediator takes the form of a surrogate potential that has the same local shape as the first-principles potential and can be evaluated efficiently to deliver atomic forces as real-time feedback. The surrogate potential is updated continuously by electronic structure calculations and guarantees to provide a reliable response to the operator for any molecular structure. To demonstrate the application of iterative electronic structure methods in real-time reactivity exploration, we implement self-consistent semi-empirical methods as the data source and a...
Improved real-time photogrammetric stitching
De Villiers, J
2013-04-01
Full Text Available and extended from one to two dimensions to allow for multiple layers or arbitrary arrangements of cameras. The incorporation of stabilisation inputs allows the stitching algorithm to provide space stabilised panoramas. The final contribution is to decrease...
Dorval, A D; Christini, D J; White, J A
2001-10-01
We describe a system for real-time control of biological and other experiments. This device, based around the Real-Time Linux operating system, was tested specifically in the context of dynamic clamping, a demanding real-time task in which a computational system mimics the effects of nonlinear membrane conductances in living cells. The system is fast enough to represent dozens of nonlinear conductances in real time at clock rates well above 10 kHz. Conductances can be represented in deterministic form, or more accurately as discrete collections of stochastically gating ion channels. Tests were performed using a variety of complex models of nonlinear membrane mechanisms in excitable cells, including simulations of spatially extended excitable structures, and multiple interacting cells. Only in extreme cases does the computational load interfere with high-speed "hard" real-time processing (i.e., real-time processing that never falters). Freely available on the worldwide web, this experimental control system combines good performance. immense flexibility, low cost, and reasonable ease of use. It is easily adapted to any task involving real-time control, and excels in particular for applications requiring complex control algorithms that must operate at speeds over 1 kHz.
花良浩; 陶涛
2015-01-01
In order to solve the problem of the human subjective detection problem on the experiment project by use of thin with non-woven fabric defect detection of traditional technology, we propose a wavelet of non-woven fabric defect detection on machine vision technology. Through the analysis of the characteristics of all kinds of defects in the frequency domain, the multi-resolution characteristics of wavelet algorithm detect defects and the experiment can detect very small holes and impurity defects. The results showed that the non-woven fabric defect real-time detection algorithm based on wavelet for millimeter size of the diameter of the impurity type defect detection effect is obvious, and greatly improve the detection speed and accuracy.%针对实验项目所使用的薄型用无纺布传统的疵点检测技术主要依靠人为的主观检测问题,提出基于小波的机器视觉的无纺布疵点检测技术,通过分析各种疵点在频域上的特性,采用具有多分辨率特性的小波算法检测疵点,实验可以检测出非常小的孔洞以及杂质型疵点,结果表明,基于小波的无纺布疵点实时检测算法对于毫米级大小直径的杂质型疵点检测效果明显,极大提升了检测速度和准确性.
Design and Implementation of An Algorithm of Real- time Shadow Rendering%一种改进的实时软阴影算法的设计与实现
张方彦; 杨猛; 刘金刚
2012-01-01
在解决实时渲染时的阴影边界走样时,常用的(Percentage Closer Filter,PCF)方法不仅效率低下,而且边界处的平滑效果也很有限.改进了PCF算法,使算法的执行效率更高,且有更好的反走样效果.首先分别以相机和光源为基准来构造裁剪坐标系,通过2次绘制来锁定产生阴影的像素区域,然后用改进的高精度滤波模板对阴影进行适应性反走样处理,使平滑操作集中在对视觉效果有重要影响的边界区域上,有选择地优化了数据,从而大幅提高了全局计算效率.实验结果证明,文中算法比常规的PCF算法在执行速度上有明显提高,效果上也得到一定程度的改善,达到了效率与效果的优化折中.%In realistic graphics, how to reflect realistic shadow effect is an important aspect to enhance the sense of reality of the model. The shadow should meet the real physical situation as far as possible, meanwhile, a smooth edge is necessary. However, rectangular array of pixels will easily cause jagged aliasing phenomenon at the edges. How to deal with the aliasing problems effectively has been a hot topic in the field of graphics. When solving aliasing of the shadow boundary in real - time rendering, the conventional Percentage Closer Filter (PCF) is not only inefficient, but also the smoothing effect of the boundary is limited. This paper improves the PCF algorithm, the improvement makes the algorithm more efficient in implementation. This new algorithm is based on conventional Shadow Mapping and uses higher accuracy of the filter template to deal with aliasing adaptively, especially to the area which has impact on visual effects, . thus increasing the overall computational efficiency substantially. The experiment results show that this algorithm is obviously improved in efficiency compared with the conventional PCF.
李明然; 贺建军
2012-01-01
针对磁悬浮系统的复杂非线性及模型不确定的特点,采用模糊PID算法对其进行控制,以满足系统对动态性能和静态性能的要求;结合PID实时控制中的经验,建立合理的模糊规则,模糊推理机构根据不同的偏差e、偏差变化率ec对PID参数Kp、Ki和Kd进行自校正;在磁悬浮实验装置中进行实时控制实验,通过与常规PID控制效果的比较来验证模糊PID控制器的性能;在系统输入存在正弦扰动时,模糊PID控制器使系统响应过程中的振荡幅度得到明显减小,干扰对控制效果的影响被减弱;实验证明,模糊PID控制器具有较强的鲁棒性和抗干扰能力,对于磁悬浮这种非线性系统具有良好的控制效果.%Aiming at the characteristics of the complex nonlinearity and uncertain model, fuzzy PID algorithm is adopted to satisfy the requirements of dynamic and static performance in the control of magnetic levitation system. Based on the experience in the real time PID control experiment, fuzzy control rules are established. According to different deviation e and deviation rate of changeec. , PID parameters Kp , K, and KdWere accomplished self tuning by fuzzy inference mechanism. The real- time control experiment is done in the magnetic levitation device in order to verify the control performance of fuzzy PIDconlroller. When system input exists sinusoidal disturbance, the oscillation amplitude cif the system in response process and the impact of interference are reduced obviously by fuzzy PID controller. The experiment proves that this fuzzy PID controller owns better robustness and stronger anti - interference and has good control performance for the nonlinear system such as magnetic levitation system.
Schneberk, D.
1985-07-01
This paper describes the analysis component of the Enrichment Diagnostic System (EDS) developed for the Atomic Vapor Laser Isotope Separation Program (AVLIS) at Lawrence Livermore National Laboratory (LLNL). Four different types of analysis are performed on data acquired through EDS: (1) absorption spectroscopy on laser-generated spectral lines, (2) mass spectrometer analysis, (3) general purpose waveform analysis, and (4) separation performance calculations. The information produced from this data includes: measures of particle density and velocity, partial pressures of residual gases, and overall measures of isotope enrichment. The analysis component supports a variety of real-time modeling tasks, a means for broadcasting data to other nodes, and a great degree of flexibility for tailoring computations to the exact needs of the process. A particular data base structure and program flow is common to all types of analysis. Key elements of the analysis component are: (1) a fast access data base which can configure all types of analysis, (2) a selected set of analysis routines, (3) a general purpose data manipulation and graphics package for the results of real time analysis. Each of these components are described with an emphasis upon how each contributes to overall system capability. 3 figs.
Real-time analysis keratometer
Adachi, Iwao P. (Inventor); Adachi, Yoshifumi (Inventor); Frazer, Robert E. (Inventor)
1987-01-01
A computer assisted keratometer in which a fiducial line pattern reticle illuminated by CW or pulsed laser light is projected on a corneal surface through lenses, a prismoidal beamsplitter quarterwave plate, and objective optics. The reticle surface is curved as a conjugate of an ideal corneal curvature. The fiducial image reflected from the cornea undergoes a polarization shift through the quarterwave plate and beamsplitter whereby the projected and reflected beams are separated and directed orthogonally. The reflected beam fiducial pattern forms a moire pattern with a replica of the first recticle. This moire pattern contains transverse aberration due to differences in curvature between the cornea and the ideal corneal curvature. The moire pattern is analyzed in real time by computer which displays either the CW moire pattern or a pulsed mode analysis of the transverse aberration of the cornea under observation, in real time. With the eye focused on a plurality of fixation points in succession, a survey of the entire corneal topography is made and a contour map or three dimensional plot of the cornea can be made as a computer readout in addition to corneal radius and refractive power analysis.
Estimating correlation for a real-time measure of connectivity.
Arunkumar, Akhil; Panday, Ashish; Joshi, Bharat; Ravindran, Arun; Zaveri, Hitten P
2012-01-01
There has recently been considerable interest in connectivity analysis of fMRI and scalp and intracranial EEG time-series. The computational requirements of the pair-wise correlation (PWC), the core time-series measure used to estimate connectivity, presents a challenge to the real-time estimation of the PWC between all pairs of multiple time-series. We describe a parallel algorithm for computing PWC in real-time for streaming data from multiple channels. The algorithm was implemented on the Intel Xeon™ and IBM Cell Broadband Engine™ platforms. We evaluated time to estimate correlation for signals recorded with different acquisition parameters as a comparison to real-time constraints. We demonstrate that the execution time of these efficient implementations meet real-time constraints in most instances.
Real-Time Obstacle Detection Approach using Stereoscopic Images
Nadia Baha
2014-02-01
Full Text Available In this paper, we propose a new and simple approach to obstacle and free space detection in an indoor and outdoor environment in real-time using stereo vision as sensor. The real-time obstacle detection algorithm uses two dimensional disparity map to detect obstacles in the scene without constructing the ground plane. The proposed approach combines an accumulating and thresholding techniques to detect and cluster obstacle pixels into objects using a dense disparity map. The results from both analysis modules are combined to provide information of the free space. Experimental results are presented to show the effectiveness of the proposed method in real-time.
孟大地; 胡玉新; 石涛; 孙蕊; 李晓波
2013-01-01
合成孔径雷达(SAR)成像处理的运算量较大，在基于中央处理器(Central Processing Unit, CPU)的工作站或服务器上一般需要耗费较长的时间，无法满足实时性要求。借助于通用并行计算架构(CUDA)编程架构，该文提出一种基于图形处理器(GPU)的SAR成像处理算法实现方案。该方案解决了GPU显存不足以容纳一景SAR数据时数据处理环节与内存/显存间数据传输环节的并行化问题，并能够支持多GPU设备的并行处理，充分利用了GPU设备的计算资源。在NVIDIA K20C和INTEL E5645上的测试表明，与传统基于GPU的SAR成像处理算法相比，该方案能够达到数十倍的速度提升，显著降低了处理设备的功耗，提高了处理设备的便携性，能够达到每秒约36兆采样点的实时处理速度。%Synthetic Aperture Radar (SAR) image processing requires a considerable amount of computational resources. Traditionally, this task runs on a workstation or a server based on Central Processing Units (CPUs) and is rather time-consuming, making real-time processing of SAR data impossible. Based on Compute Unified Device Architecture (CUDA) technology, a new plan for a SAR imaging algorithm operated on an NVIDIA Graphic Processing Unit (GPU) is proposed. The new proposal makes it possible for the data processing procedure and the CPU/GPU data exchange to execute concurrently, especially when the size of SAR data exceeds the total GPU global memory size. A multi-GPU is suitably supported by the new proposal, and all computational resources are fully exploited. It has been shown by an experiment on an NVIDIA K20C and INTEL E5645 that the proposed solution accelerates SAR data processing by tens of times. Consequently, a GPU based SAR processing system that embeds the proposed solution is much more efficient and portable, thereby making it qualified to be a real-time SAR data processing system. Experiments showed that SAR data can be
陈珂; 吴建平; 李金祥; 许旻; 鲜学丰; 顾才东
2015-01-01
The state of the art in circle detection usually resorts to edge pixels as the voting components to perform parametric accumulation in 2D or 3D space, which generally incurs high computational cost and is thus unable to meet the real-time processing requirements in complex natural scene processing. Using edge sections as voting components, this paper presents a robust real-time circle detection algorithm based on 1D probabilistic Hough Transform. The algorithm first segments Canny edges based on their gradient directions into arc sections, from which seed sections meeting certain curvature criteria are selected. For each seed, a probability-weighted 1D Hough accumulation is then built along the radius dimension to detect a valid circle related to the seed and estimate the initial radius of the circle based on the peak magnitude and peak position of the 1D accumulation. Finally direct circular least square fitting is employed to further pinpoint the radius and center information for the detected circle. The experiment shows, when appropriate segmentation thre-sholds are chosen, the algorithm significantly outperforms the state of the art in processing speed while maintaining high reliability as far as the circle detection in complex natural scene images is concerned.%针对现有圆检测算法以像素为投票主体在二维或三维空间进行参数累积，运算复杂度高，难以达到复杂自然场景中的实时检测要求的问题，提出一种以线段为投票主体并基于一维概率 Hough 变换的实时圆检测算法。首先基于梯度方向对 Canny 边缘像素实施逐段分割，从中选取满足一定曲率条件的线段作为种子，对每个种子沿半径进行一维概率 Hough 累积；然后根据峰值大小和位置提取有效圆及其初始半径；最后利用圆的直接最小二乘拟合进一步定位圆半径和圆心。对复杂的自然场景图像进行实验的结果表明，通过选取合适的分割阈值，该
Real time lobster posture estimation for behavior research
Yan, Sheng; Alfredsen, Jo Arve
2017-02-01
In animal behavior research, the main task of observing the behavior of an animal is usually done manually. The measurement of the trajectory of an animal and its real-time posture description is often omitted due to the lack of automatic computer vision tools. Even though there are many publications for pose estimation, few are efficient enough to apply in real-time or can be used without the machine learning algorithm to train a classifier from mass samples. In this paper, we propose a novel strategy for the real-time lobster posture estimation to overcome those difficulties. In our proposed algorithm, we use the Gaussian mixture model (GMM) for lobster segmentation. Then the posture estimation is based on the distance transform and skeleton calculated from the segmentation. We tested the algorithm on a serials lobster videos in different size and lighting conditions. The results show that our proposed algorithm is efficient and robust under various conditions.
Facial landmark detection in real-time with correlation filtering
Contreras, Viridiana; Díaz-Ramírez, Víctor H.
2016-09-01
An algorithm for facial landmark detection based on template matched filtering is presented. The algorithm is able to detect and estimate the position of a set of prespecified landmarks by employing a bank of linear filters. Each filter in the bank is trained to detect a single landmark that is located in a small region of the input face image. The filter bank is implemented in parallel on a graphics processing unit to perform facial landmark detection in real-time. Computer simulation results obtained with the proposed algorithm are presented and discussed in terms of detection rate, accuracy of landmark location estimation, and real-time efficiency.
The Dynamic Checking of Complex Real Time System
YU Chao; HUANG Benwen; WU Guoqing
2006-01-01
The paper presents an dynamic execution model of complex real-time software based on requirement description model RTRSM, and then propose a checking method based on configuration covering and its corresponding algorithm. This checking method can check the execution situations between parallel elements in a dynamic execution step of real-time software systems. It also can check all the states and transitions which assure the completeness of checking. In the end, related theorem is proofed.
Real-time simulation of dissipation-driven quantum systems
Banerjee, Debasish; Jiang, Fu-Jiun; Kon, Mark; Wiese, Uwe-Jens
2015-01-01
We set up a real-time path integral to study the evolution of quantum systems driven in real-time completely by the coupling of the system to the environment. For specifically chosen interactions, this can be interpreted as measurements being performed on the system. For a spin-1/2 system, in particular, when the measurement results are averaged over, the resulting sign problem completely disappears, and the system can be simulated with an efficient cluster algorithm.
Incremental Activation Detection for Real-Time fMRI Series Using Robust Kalman Filter
Liang Li
2014-01-01
Full Text Available Real-time functional magnetic resonance imaging (rt-fMRI is a technique that enables us to observe human brain activations in real time. However, some unexpected noises that emerged in fMRI data collecting, such as acute swallowing, head moving and human manipulations, will cause much confusion and unrobustness for the activation analysis. In this paper, a new activation detection method for rt-fMRI data is proposed based on robust Kalman filter. The idea is to add a variation to the extended kalman filter to handle the additional sparse measurement noise and a sparse noise term to the measurement update step. Hence, the robust Kalman filter is designed to improve the robustness for the outliers and can be computed separately for each voxel. The algorithm can compute activation maps on each scan within a repetition time, which meets the requirement for real-time analysis. Experimental results show that this new algorithm can bring out high performance in robustness and in real-time activation detection.
A constrained ICA approach for real-time cardiac artifact rejection in magnetoencephalography.
Breuer, Lukas; Dammers, Jürgen; Roberts, Timothy P L; Shah, N Jon
2014-02-01
Recently, magnetoencephalography (MEG)-based real-time brain computing interfaces (BCI) have been developed to enable novel and promising methods of neuroscience research and therapy. Artifact rejection prior to source localization largely enhances the localization accuracy. However, many BCI approaches neglect real-time artifact removal due to its time consuming processing. With cardiac artifact rejection for real-time analysis (CARTA), we introduce a novel algorithm capable of real-time cardiac artifact (CA) rejection. The method is based on constrained independent component analysis (ICA), where a priori information of the underlying source signal is used to optimize and accelerate signal decomposition. In CARTA, this is performed by estimating the subject's individual density distribution of the cardiac activity, which leads to a subject-specific signal decomposition algorithm. We show that the new method is capable of effectively reducing CAs within one iteration and a time delay of 1 ms. In contrast, Infomax and Extended Infomax ICA converged not until seven iterations, while FastICA needs at least ten iterations. CARTA was tested and applied to data from three different but most common MEG systems (4-D-Neuroimaging, VSM MedTech Inc., and Elekta Neuromag). Therefore, the new method contributes to reliable signal analysis utilizing BCI approaches.
Incremental activation detection for real-time fMRI series using robust Kalman filter.
Li, Liang; Yan, Bin; Tong, Li; Wang, Linyuan; Li, Jianxin
2014-01-01
Real-time functional magnetic resonance imaging (rt-fMRI) is a technique that enables us to observe human brain activations in real time. However, some unexpected noises that emerged in fMRI data collecting, such as acute swallowing, head moving and human manipulations, will cause much confusion and unrobustness for the activation analysis. In this paper, a new activation detection method for rt-fMRI data is proposed based on robust Kalman filter. The idea is to add a variation to the extended kalman filter to handle the additional sparse measurement noise and a sparse noise term to the measurement update step. Hence, the robust Kalman filter is designed to improve the robustness for the outliers and can be computed separately for each voxel. The algorithm can compute activation maps on each scan within a repetition time, which meets the requirement for real-time analysis. Experimental results show that this new algorithm can bring out high performance in robustness and in real-time activation detection.
D. Sudharsan
2012-03-01
Full Text Available Wireless Sensor Network (WSN is well known for distributed real time systems for various applications. In order to handle the increasing functionality and complexity of high resolution spatio-temporal sensorydatabase, there is a strong need for a system/tool to analyse real time data associated with distributed sensor network systems. There are a few package/systems available to maintain the near real time database system/management, which are expensive and requires expertise. Hence, there is a need for a cost effective and easy to use dynamic real-time data repository system to provide real time data (raw as well as usable units in a structured format. In the present study, a distributed sensor network system, with Agrisens (AS and FieldServer (FS as well as FS-based Flux Tower and FieldTwitter, is used, which consists of network of sensors and field images to observe/collect the real time weather, crop and environmental parameters for precision agriculture. The real time FieldServer-based spatio-temporal high resolution dynamic sensory data was converted into Dynamic Real-Time Database Management System (DRTDBMS in a structured format for both raw and converted (with usable units data. A web interface has been developed to access the DRTDBMS and exclusive domain has been created with the help of open/free Information and Communication Technology (ICT tools in Extendable Markup Language (XML using (Hypertext preprocessor PHP algorithms and with eXtensible Hyper Text Markup Language (XHTML self-scripting. The proposed DRTDBMS prototype, called GeoSense DRTDBMS, which is a part of the ongoing IndoJapan initiative ‘ICT and Sensor Network based Decision Support Systems in Agriculture and EnvironmentAssessment’, will be integrated with GeoSense cloud server to provide database (dynamic real-time weather/soil/crop and environmental parameters and modeling services (crop water requirement and simulated rice yield modeling. GeoSense-cloud server
EXTENDED MONTE CARLO LOCALIZATION ALGORITHM FOR MOBILE SENSOR NETWORKS
无
2008-01-01
A real-world localization system for wireless sensor networks that adapts for mobility and irregular radio propagation model is considered.The traditional range-based techniques and recent range-free localization schemes are not welt competent for localization in mobile sensor networks,while the probabilistic approach of Bayesian filtering with particle-based density representations provides a comprehensive solution to such localization problem.Monte Carlo localization is a Bayesian filtering method that approximates the mobile node’S location by a set of weighted particles.In this paper,an enhanced Monte Carlo localization algorithm-Extended Monte Carlo Localization (Ext-MCL) is suitable for the practical wireless network environment where the radio propagation model is irregular.Simulation results show the proposal gets better localization accuracy and higher localizable node number than previously proposed Monte Carlo localization schemes not only for ideal radio model,but also for irregular one.
MCMC with Strings and Branes: The Suburban Algorithm (Extended Version)
Heckman, Jonathan J; Vigoda, Ben
2016-01-01
Motivated by the physics of strings and branes, we develop a class of Markov chain Monte Carlo (MCMC) algorithms involving extended objects. Starting from a collection of parallel Metropolis-Hastings (MH) samplers, we place them on an auxiliary grid, and couple them together via nearest neighbor interactions. This leads to a class of "suburban samplers" (i.e., spread out Metropolis). Coupling the samplers in this way modifies the mixing rate and speed of convergence for the Markov chain, and can in many cases allow a sampler to more easily overcome free energy barriers in a target distribution. We test these general theoretical considerations by performing several numerical experiments. For suburban samplers with a fluctuating grid topology, performance is strongly correlated with the average number of neighbors. Increasing the average number of neighbors above zero initially leads to an increase in performance, though there is a critical connectivity with effective dimension d_eff ~ 1, above which "groupthin...
Extended Range Guided Munition Parameter Optimization Based on Genetic Algorithms
无
2005-01-01
Many factors influencing range of extended range guided munition (ERGM) are analyzed. The definition domain of the most important three parameters are ascertained by preparatory mathematical simulation, the optimized mathematical model of ERGM maximum range with boundary conditions is created, and parameter optimization based on genetic algorithm (GA) is adopted. In the GA design, three-point crossover is used and the best chromosome is kept so that the convergence speed becomes rapid. Simulation result shows that GA is feasible, the result is good and it can be easy to attain global optimization solution, especially when the objective function is not the convex one for independent variables and it is a multi-parameter problem.
Autonomous Real Time Requirements Tracing
Plattsmier, George; Stetson, Howard
2014-01-01
One of the more challenging aspects of software development is the ability to verify and validate the functional software requirements dictated by the Software Requirements Specification (SRS) and the Software Detail Design (SDD). Insuring the software has achieved the intended requirements is the responsibility of the Software Quality team and the Software Test team. The utilization of Timeliner-TLX(sup TM) Auto- Procedures for relocating ground operations positions to ISS automated on-board operations has begun the transition that would be required for manned deep space missions with minimal crew requirements. This transition also moves the auto-procedures from the procedure realm into the flight software arena and as such the operational requirements and testing will be more structured and rigorous. The autoprocedures would be required to meet NASA software standards as specified in the Software Safety Standard (NASASTD- 8719), the Software Engineering Requirements (NPR 7150), the Software Assurance Standard (NASA-STD-8739) and also the Human Rating Requirements (NPR-8705). The Autonomous Fluid Transfer System (AFTS) test-bed utilizes the Timeliner-TLX(sup TM) Language for development of autonomous command and control software. The Timeliner-TLX(sup TM) system has the unique feature of providing the current line of the statement in execution during real-time execution of the software. The feature of execution line number internal reporting unlocks the capability of monitoring the execution autonomously by use of a companion Timeliner-TLX(sup TM) sequence as the line number reporting is embedded inside the Timeliner-TLX(sup TM) execution engine. This negates I/O processing of this type data as the line number status of executing sequences is built-in as a function reference. This paper will outline the design and capabilities of the AFTS Autonomous Requirements Tracker, which traces and logs SRS requirements as they are being met during real-time execution of the
Scheduling Non-stationary Bursts of Real-time and Non-real-time Traffic in ATM Networks
无
2000-01-01
The problem of scheduling real-time and non-real-time traffic in an ATM switch multiplexor when bursts of either type of traffic occur is studied. The scheduling algorithms studied are: Queue Length Threshold (QLT) and Minimum Laxity Threshold (MLT). Analytic results based on Markov Chains are used. In addition the results are compared with an optimal (but impractical) scheduling determined via dynamic programming. Dynamic programming is used in this paper to show that MLT gives a near optimal performance trade-off between real-time and non-real-time traffic for constant arrival rates. The trade-off QLT allows is not close to optimal. For non-real-time bursts MLT still gives a close to optimal trade-off. For real-time bursts the trade-off MLT allows between real-time and non-real-time traffic is not as close to optimal, but even where the MLT trade-off is not near optimal, the QLT trade-off is much worse than the MLT trade-off.
Rigorous Modeling of Real-time System Based on UML and PVS
LAI Ming-zhi; YOU Jin-yuan
2005-01-01
Rigorous modeling could improve the correctness and reduce cost in embedded real-time system development for models could be verified. Tools are needed for rigorous modeling of embedded real-time system. UML is an industrial standard modeling language which provides a powerful expressi-veness, intuitive and easy to use interface to model. UML is widely accepted by software developer. However, for lack of precisely defined semantics, especially on the dynamic diagrams, UML model is hard to be verified. PVS is a general formal method which provides a high-order logic specification language and integrated with model checking and theorem proving tools. Combining the widely used UML with PVS, this paper provides a novel modeling and verification approach for embedded real-time system. In this approach, we provide 1) a timed extended UML statechart for modeling dynamic behavior of an embedded real-time system; 2) an approach to capture timed automata based semantics from timed statechart; and 3) an algorithm to generate a finite state model expressed in PVS specification for model checking. The benefits of our approach include flexible and friendly in modeling, extendable in formalization and verification content, and better performance. Time constraints are modeled and verified and its a highlight of this paper.
The Real Time Mixing Module Design for HDTV Data of SMPTE 274M and PC Video Data
魏江力; 赵保军; 韩月秋
2003-01-01
A real time mixing module for high definition television (HDTV) data of SMPTE 274M and PC video data is designed. The hardware implementation, algorithm and simulation of the mixing module are given. In order to improve the capability of data processing, an anti-fuse FPGA chip and a mechanism of pipelining and modularization are adopted. With 6 parallel LUTs and a fast algorithm, it can mix 4∶2∶2 component signals in luminance and chrominance space respectively in real time. According to the simulation, the module has the ability to mix the uncompressed HDTV data with PC video data in real time, which can not be fulfilled by current ASIC chips. Furthermore, it can be extended to multi-stage mixing with the thoughts implied by the design. The mixing module can be widely used in HDTV production systems.
基于视频投影法的交通拥挤实时检测算法%Video-based projecting algorithm for real-time traffic congestion detection
张新; 常云涛; 郭佳宁; 谢平红
2013-01-01
Aiming at the growing problem of urban traffic congestion,a video-based projecting algorithm to detect the real-time traffic congestion on the urban road is proposed.Firstly by video projecting method,two-dimensional lane is transformed into one-dimensional line segment,the scanning line method is used to obtain lane occupation rate,and the exponential smoothing formula is used to remove the noise in the source data.Then considering the lane occupation rate and its variance as the traffic characteristic parameters,the traffic congestion detection model is established and used to process three sections of traffic video.The results detected by the model are compared with those detected by artificial judgment,and it is showed that the correct detecting rate is above 92％ by the proposed algorithm,thus demonstrating the validity of the algorithm.%针对日益严重的城市道路交通拥挤问题,文章提出了基于视频检测技术实时判断道路交通拥挤的算法.首先通过视频投影法将二维车道转化为一维线段,再通过扫描线段方法获取车道占有率,然后用指数平滑公式对提取出的车道占有率进行去噪处理,接着以道路占有率、占有率方差为交通特征参数,建立交通拥挤识别模型,最后使用模型对3段实例视频进行处理,用模型识别出的结果与人工判断的结果进行对比分析,得出使用模型进行拥挤识别的正确率在92％以上,证明了模型的有效性.
Lai, C.; Tsay, T.-K.; Chien, C.-H.; Wu, I.-L.
2009-01-01
Researchers at the Hydroinformatic Research and Development Team (HIRDT) of the National Taiwan University undertook a project to create a real time flood forecasting model, with an aim to predict the current in the Tamsui River Basin. The model was designed based on deterministic approach with mathematic modeling of complex phenomenon, and specific parameter values operated to produce a discrete result. The project also devised a rainfall-stage model that relates the rate of rainfall upland directly to the change of the state of river, and is further related to another typhoon-rainfall model. The geographic information system (GIS) data, based on precise contour model of the terrain, estimate the regions that were perilous to flooding. The HIRDT, in response to the project's progress, also devoted their application of a deterministic model to unsteady flow of thermodynamics to help predict river authorities issue timely warnings and take other emergency measures.
REAL TIME DATA PROCESSING FRAMEWORKS
Yash Sakaria
2015-09-01
Full Text Available On a business level, everyone wants to get hold of the business value and other organizational advantages that big data has to offer. Analytics has arisen as the primitive path to business value from big data. Hadoop is not just a storage platform for big data; it’s also a computational and processing platform for business analytics. Hadoop is, however, unsuccessful in fulfilling business requirements when it comes to live data streaming. The initial architecture of Apache Hadoop did not solve the problem of live stream data mining. In summary, the traditional approach of big data being co-relational to Hadoop is false; focus needs to be given on business value as well. Data Warehousing, Hadoop and stream processing complement each other very well. In this paper, we have tried reviewing a few frameworks and products which use real time data streaming by providing modifications to Hadoop.
THE DLSTRIBOTED MCU MODEL FOR SYNCHRONOUS REAL-TIME TELETEACHING
刘均; 李人厚; 郑庆华
2004-01-01
Aiming at issues on multimedia communication in synchronous real-time teleteaching (SRT) systems over IP network, a 4-tuple structural mode of multimedia communication is proposed in the paper, and an SRT-oriented distributed MCU model is built according to the mode. Moreover, the mechanism of multicast communication across subnets is discussed. The distributed MCU model has been applied successfully in our interactive synchronous real-time telesteaching system RealClass and has shown good extendibility in operation.
Logic Model Checking of Time-Periodic Real-Time Systems
Florian, Mihai; Gamble, Ed; Holzmann, Gerard
2012-01-01
In this paper we report on the work we performed to extend the logic model checker SPIN with built-in support for the verification of periodic, real-time embedded software systems, as commonly used in aircraft, automobiles, and spacecraft. We first extended the SPIN verification algorithms to model priority based scheduling policies. Next, we added a library to support the modeling of periodic tasks. This library was used in a recent application of the SPIN model checker to verify the engine control software of an automobile, to study the feasibility of software triggers for unintended acceleration events.
Towards real time speckle controlled retinal photocoagulation
Bliedtner, Katharina; Seifert, Eric; Stockmann, Leoni; Effe, Lisa; Brinkmann, Ralf
2016-03-01
Photocoagulation is a laser treatment widely used for the therapy of several retinal diseases. Intra- and inter-individual variations of the ocular transmission, light scattering and the retinal absorption makes it impossible to achieve a uniform effective exposure and hence a uniform damage throughout the therapy. A real-time monitoring and control of the induced damage is highly requested. Here, an approach to realize a real time optical feedback using dynamic speckle analysis is presented. A 532 nm continuous wave Nd:YAG laser is used for coagulation. During coagulation, speckle dynamics are monitored by a coherent object illumination using a 633nm HeNe laser and analyzed by a CMOS camera with a frame rate up to 1 kHz. It is obvious that a control system needs to determine whether the desired damage is achieved to shut down the system in a fraction of the exposure time. Here we use a fast and simple adaption of the generalized difference algorithm to analyze the speckle movements. This algorithm runs on a FPGA and is able to calculate a feedback value which is correlated to the thermal and coagulation induced tissue motion and thus the achieved damage. For different spot sizes (50-200 μm) and different exposure times (50-500 ms) the algorithm shows the ability to discriminate between different categories of retinal pigment epithelial damage ex-vivo in enucleated porcine eyes. Furthermore in-vivo experiments in rabbits show the ability of the system to determine tissue changes in living tissue during coagulation.
ROBUST MEMORY MANAGEMENT USING REAL TIME CONCEPTS
V. Karthikeyan
2014-01-01
Full Text Available Memory fragmentation is the development of a large number of separate free areas. Memory management in embedded systems demand effective implementation schemes to avoid fragmentation problem. Existing dynamic memory allocation methods fail to suit real time system requirements. Execution times need to be deterministic and this motivates the need for allocation and deallocation to be done in constant time with the help of API’s. In µC/OS-II, memory allocation is semi-dynamic and a buddy allocator dynamic memory allocation algorithm is commonly used. Programmer must statically allocate a memory and partition the region using µC/OS-II Kernel API. Tasks can only request pre-partitioned fixed-size memory space from µC/OS-II. Memory allocation times are influenced by the ratio of memory allocation to the stack size of the task. In this research work memory management in LPC 1768 environment using RTOS µC/OS-II is proposed. Effective sharing of memory blocks among tasks co exists with partition. The captured results shows that the memory allocation and deallocation suits real time. The implication of the work is that, the necessity to reserve a static set of locations ahead of time is eliminated so that memory can be allocated at compile or design time.
Clinical virology in real time.
Niesters, Hubert G M
2002-12-01
The ability to detect nucleic acids has had and still has a major impact on diagnostics in clinical virology. Both quantitative and qualitative techniques, whether signal or target amplification based systems, are currently used routinely in most if not all virology laboratories. Technological improvements, from automated sample isolation to real time amplification technology, have given the ability to develop and introduce systems for most viruses of clinical interest, and to obtain clinical relevant information needed for optimal antiviral treatment options. Both polymerase chain reaction (PCR) and nucleic acid sequence-based amplification (NASBA) can currently be used together with real time detection to generate results in a short turn-around time and to determine whether variants relevant for antiviral resistance are present. These new technologies enable the introduction of an individual patient disease management concept. Within our clinical setting, we have introduced this e.g. for quantitative detection of Epstein-Barr Virus (EBV) in T-dell depleted allogeneic stem cell transplant patients. This enabled us to develop models for pre-emptive anti B-cell immunotherapy for EBV reactivation, thereby effectively reducing not the incidence of EBV-lymphoproliferative disease but the virus related mortality. Furthermore, additional clinically relevant viruses can now easily be detected simultaneously. It also becomes more feasible to introduce molecular testing for those viruses that can easily be detected using classical virological methods, like culture techniques or antigen detection. Prospective studies are needed to evaluate the clinical importance of the additional positive samples detected. It should however be made clear that a complete exchange of technologies is unlikely to occur, and that some complementary technologies should stay operational enabling the discovery of new viruses. The implementation of these molecular diagnostic technologies furthermore
Real-time estimation of dynamic functional connectivity networks.
Monti, Ricardo Pio; Lorenz, Romy; Braga, Rodrigo M; Anagnostopoulos, Christoforos; Leech, Robert; Montana, Giovanni
2017-01-01
Two novel and exciting avenues of neuroscientific research involve the study of task-driven dynamic reconfigurations of functional connectivity networks and the study of functional connectivity in real-time. While the former is a well-established field within neuroscience and has received considerable attention in recent years, the latter remains in its infancy. To date, the vast majority of real-time fMRI studies have focused on a single brain region at a time. This is due in part to the many challenges faced when estimating dynamic functional connectivity networks in real-time. In this work, we propose a novel methodology with which to accurately track changes in time-varying functional connectivity networks in real-time. The proposed method is shown to perform competitively when compared to state-of-the-art offline algorithms using both synthetic as well as real-time fMRI data. The proposed method is applied to motor task data from the Human Connectome Project as well as to data obtained from a visuospatial attention task. We demonstrate that the algorithm is able to accurately estimate task-related changes in network structure in real-time. Hum Brain Mapp 38:202-220, 2017. © 2016 Wiley Periodicals, Inc.
Near real-time stereo vision system
Anderson, Charles H. (Inventor); Matthies, Larry H. (Inventor)
1993-01-01
The apparatus for a near real-time stereo vision system for use with a robotic vehicle is described. The system is comprised of two cameras mounted on three-axis rotation platforms, image-processing boards, a CPU, and specialized stereo vision algorithms. Bandpass-filtered image pyramids are computed, stereo matching is performed by least-squares correlation, and confidence ranges are estimated by means of Bayes' theorem. In particular, Laplacian image pyramids are built and disparity maps are produced from the 60 x 64 level of the pyramids at rates of up to 2 seconds per image pair. The first autonomous cross-country robotic traverses (of up to 100 meters) have been achieved using the stereo vision system of the present invention with all computing done onboard the vehicle. The overall approach disclosed herein provides a unifying paradigm for practical domain-independent stereo ranging.
CONSIDERATIONS ON REAL TIME DATA WAREHOUSING (RTDW
Marius Bogdan DINU
2014-05-01
Full Text Available The RTDW concept originated in the early 2000s. By that time, computing power had increased to a level that was allowing extraction of data collections for reporting purposes. Such collections were used almost in real time and at speeds nearly comparable to what an operation system was capable to deliver. The main idea will be to eliminate some of the components of the classic extraction process which is basically the most costly factor less time - consuming. We anticipate that the following factors will be decisive: elimination of batch-type processes [1], data compression techniques, data capture techniques, ability to keep in cache a large volume of data, parallel processing, and data mining algorithms that can adapt to such applications.
Mobile real time radiography system
Vigil, J.; Taggart, D.; Betts, S. [Los Alamos National Lab., NM (United States)] [and others
1997-11-01
A 450-keV Mobile Real Time Radiography (RTR) System was delivered to Los Alamos National Laboratory (LANL) in January 1996. It was purchased to inspect containers of radioactive waste produced at (LANL). Since its delivery it has been used to radiograph more than 600 drums of radioactive waste at various LANL sites. It has the capability of inspecting waste containers of various sizes from <1-gal. buckets up to standard waste boxes (SWB, dimensions 54.5 in. x 71 in. x 37 in.). It has three independent x-ray acquisition formats. The primary system used is a 12- in. image intensifier, the second is a 36-in. linear diode array (LDA) and the last is an open system. It is fully self contained with on board generator, HVAC, and a fire suppression system. It is on a 53-ft long x 8-ft. wide x 14-ft. high trailer that can be moved over any highway requiring only an easily obtainable overweight permit because it weights {approximately}38 tons. It was built to conform to industry standards for a cabinet system which does not require an exclusion zone. The fact that this unit is mobile has allowed us to operate where the waste is stored, rather than having to move the waste to a fixed facility.
Real Time Scheduling Services for Distributed RT-CORBA Applications
Bineta Tresa Mathew
2012-12-01
Full Text Available Distributed computing environment is flexible to control in complex embedded systems and their software components gain complexity when these systems are equipped with many microcontrollers and software object which covers diverse platforms, this system is called as DRE system. These DRE systems need new inter-object communication solution thus QoS-enabled middleware services and mechanisms have begun to emerge. Real-time application domain benefit from flexible and open distributed architectures, such as those defined by the CORBA specification. CORBA is well-suited to conventional request/response applications, but not suited to real-time applications due to the lack of QoS features and performance optimizations. The paper shows the design and implementation of the high performance scheduling technique for the real time applications domain with CORBA systems. Four different algorithms are compared by using attributes of real time tasks constraints based on CORBA specification such as RMS, MLF, MUF and EDF.
Extending Algorithm of RSA Algorithm%基于RSA算法的扩展算法
张延招
2011-01-01
The security of RSA is designed on the basis of the difficulty of large integer decomposition.In the RSA public key encryption system the public key n is the product of two large prime number,aiming at the large integer n decomposition of the form n=pq（in which p,q as large prime number）.The paper describes the encryption and decryption theory of extending RSA algorithm,aiming at the large integer n decomposition to the form n=p1,p2,…,pr（in which p1,p2,…,pr as large prime number）.The addition of prime number could enhance the security of RSA algorithm.Compared to RSA algorithm,the extending RSA algorithm could be applied to both digital encryption/decryption and digital signature.Digital signature algorithm based on extending RSA algorithm is also of high security and reliability.%RSA的安全性是依据大整数分解的困难性而设计的。RSA公开密钥加密体制中n为2个大素数的乘积,即针对n=pq（p,q为大素数）的大整数分解,这里介绍了RSA算法的扩展算法的加密和解密原理,即针对n=p1,p2,…,pr（p1,p2,…,pr为大素数）的大整数分解。通过扩展素因子的个数达到RSA算法的安全性。比较RSA算法,扩展的RSA算法不仅可用于数据加密解密,也可用于数字签名。利用扩展的RSA算法实现数字签名也具有较高的安全性和可靠性。
Extended Approach to Water Flow Algorithm for Text Line Segmentation
Darko Brodi(c)
2012-01-01
This paper proposes a new approach to the water flow algorithm for text line segmentation.In the basic method the hypothetical water flows under few specified angles which have been defined by water flow angle as parameter.It is applied to the document image frame from left to right and vice versa.As a result,the unwetted and wetted areas are established.Thesc areas separate text from non-text elements in each text line,respectively.Hence,they represent the control areas that are of major importance for text line segmentation.Primarily,an extended approach means extraction of the connected-components by bounding boxes ovcr text.By this way,each connected component is mutually separated.Hence,the water flow angle,which defines the unwetted areas,is determined adaptively.By choosing appropriate water flow angle,the unwetted areas are lengthening which leads to the better text line segmentation.Results of this approach are encouraging due to the text line segmentation improvement which is the most challenging step in document image processing.
Can Real-Time Data Also Be Climate Quality?
Brewer, M.; Wentz, F. J.
2015-12-01
GMI, AMSR-2 and WindSat herald a new era of highly accurate and timely microwave data products. Traditionally, there has been a large divide between real-time and re-analysis data products. What if these completely separate processing systems could be merged? Through advanced modeling and physically based algorithms, Remote Sensing Systems (RSS) has narrowed the gap between real-time and research-quality. Satellite microwave ocean products have proven useful for a wide array of timely Earth science applications. Through cloud SST capabilities have enormously benefited tropical cyclone forecasting and day to day fisheries management, to name a few. Oceanic wind vectors enhance operational safety of shipping and recreational boating. Atmospheric rivers are of import to many human endeavors, as are cloud cover and knowledge of precipitation events. Some activities benefit from both climate and real-time operational data used in conjunction. RSS has been consistently improving microwave Earth Science Data Records (ESDRs) for several decades, while making near real-time data publicly available for semi-operational use. These data streams have often been produced in 2 stages: near real-time, followed by research quality final files. Over the years, we have seen this time delay shrink from months or weeks to mere hours. As well, we have seen the quality of near real-time data improve to the point where the distinction starts to blur. We continue to work towards better and faster RFI filtering, adaptive algorithms and improved real-time validation statistics for earlier detection of problems. Can it be possible to produce climate quality data in real-time, and what would the advantages be? We will try to answer these questions…
Real-time Position Control of Concentric Tube Robots.
Dupont, Pierre E; Lock, Jesse; Itkowitz, Brandon
2010-05-03
A novel approach to constructing robots is based on concentrically combining pre-curved elastic tubes. By rotating and extending the tubes with respect to each other, their curvatures interact elastically to position and orient the robot's tip, as well as to control the robot's shape along its length. Since these robots form slender curves, they are well suited for minimally invasive medical procedures. A substantial challenge to their practical use is the real-time solution of their kinematics that are described by differential equations with split boundary equations. This paper proposes a numerically efficient approach to real-time position control. It is shown that the forward kinematics are smooth functions that can be pre-computed and accurately approximated using Fourier series. The inverse kinematics can be solved in real time using root finding applied to the functional approximation. Experimental demonstration of real-time position control using this approach is also described.
Students Collecting Real time Data
Miller, P.
2006-05-01
Students Collecting Real-Time Data The Hawaiian Islands Humpback Whale National Marine Sanctuary has created opportunities for middle and high school students to become Student Researchers and to be involved in real-time marine data collection. It is important that we expose students to different fields of science and encourage them to enter scientific fields of study. The Humpback Whale Sanctuary has an education visitor center in Kihei, Maui. Located right on the beach, the site has become a living classroom facility. There is a traditional Hawaiian fishpond fronting the property. The fishpond wall is being restored, using traditional methods. The site has the incredible opportunity of incorporating Hawaiian cultural practices with scientific studies. The Sanctuary offers opportunities for students to get involved in monitoring and data collection studies. Invasive Seaweed Study: Students are collecting data on invasive seaweed for the University of Hawaii. They pull a large net through the shallow waters. Seaweed is sorted, identified and weighed. The invasive seaweeds are removed. The data is recorded and sent to UH. Remote controlled monitoring boats: The sanctuary has 6 boogie board sized remote controlled boats used to monitor reefs. Boats have a camera with lights on the underside. The boats have water quality monitoring devices and GPS units. The video from the underwater camera is transmitted via a wireless transmission. Students are able to monitor the fish, limu and invertebrate populations on the reef and collect water quality data via television monitors or computers. The boat can also pull a small plankton tow net. Data is being compiled into data bases. Artificial Reef Modules: The Sanctuary has a scientific permit from the state to build and deploy artificial reef modules. High school students are designing and building modules. These are deployed out in the Fishpond fronting the Sanctuary site and students are monitoring them on a weekly basis
Lightweight distributed computing for intraoperative real-time image guidance
Suwelack, Stefan; Katic, Darko; Wagner, Simon; Spengler, Patrick; Bodenstedt, Sebastian; Röhl, Sebastian; Dillmann, Rüdiger; Speidel, Stefanie
2012-02-01
In order to provide real-time intraoperative guidance, computer assisted surgery (CAS) systems often rely on computationally expensive algorithms. The real-time constraint is especially challenging if several components such as intraoperative image processing, soft tissue registration or context aware visualization are combined in a single system. In this paper, we present a lightweight approach to distribute the workload over several workstations based on the OpenIGTLink protocol. We use XML-based message passing for remote procedure calls and native types for transferring data such as images, meshes or point coordinates. Two different, but typical scenarios are considered in order to evaluate the performance of the new system. First, we analyze a real-time soft tissue registration algorithm based on a finite element (FE) model. Here, we use the proposed approach to distribute the computational workload between a primary workstation that handles sensor data processing and visualization and a dedicated workstation that runs the real-time FE algorithm. We show that the additional overhead that is introduced by the technique is small compared to the total execution time. Furthermore, the approach is used to speed up a context aware augmented reality based navigation system for dental implant surgery. In this scenario, the additional delay for running the computationally expensive reasoning server on a separate workstation is less than a millisecond. The results show that the presented approach is a promising strategy to speed up real-time CAS systems.
基于GP U的实时水面场景并行渲染算法%Gpu-Based Real-Time Parallel Algorithm for Rendering Water-Surface Scene
孙君; 秦勃
2014-01-01
The simulation of water surface has always been a problem.In recent years,with the rapid development of graphic processing unit (GPU),its function is no longer confined to graphic processing, but enters into the field of general-purpose computing,so we can take advantage of GPU parallel com-puting to accelerate the process of water surface simulation.The main content of this paper is the real-time simulation of sea surface.The sea surface rendering algorithm uses the proj ected grid technology. The calculation of vertex coordinates of proj ected grid using the CUDA parallel computing technology were accelerated,compared the speed of calculating a large amount of data using CPU to calculating a large amount of data using GPU.Finally,the program improved rendering speed significantly,so that the program can generate a more realistic picture,while maintaining a satisfactory frame rate.%水面的模拟历来都是一个难题。近几年，随着图形处理器(GPU)的迅速发展，它的功能不再局限于图形处理，而是进入到了通用计算领域，所以可以利用 GPU 的并行计算优势来加速水面的模拟过程。本文研究的主要内容是海浪的实时模拟绘制。海浪渲染算法使用了投影网格技术，使用 CUDA并行计算方法对投影网格顶点坐标的计算进行加速，比较使用 CPU 进行大数据量计算和使用 GPU 进行大数据量计算的速度差异。最终，改进后的程序渲染速度大幅提高，使得程序可以在生成更逼真画面的同时保持令人满意的帧率。
Real-Time Analysis and Forecasting of Multisite River Flow Using a Distributed Hydrological Model
Mingdong Sun
2014-01-01
Full Text Available A spatial distributed hydrological forecasting system was developed to promote the analysis of river flow dynamic state in a large basin. The research presented the real-time analysis and forecasting of multisite river flow in the Nakdong River Basin using a distributed hydrological model with radar rainfall forecast data. A real-time calibration algorithm of hydrological distributed model was proposed to investigate the particular relationship between the water storage and basin discharge. Demonstrate the approach of simulating multisite river flow using a distributed hydrological model couple with real-time calibration and forecasting of multisite river flow with radar rainfall forecasts data. The hydrographs and results exhibit that calibrated flow simulations are very approximate to the flow observation at all sites and the accuracy of forecasting flow is gradually decreased with lead times extending from 1 hr to 3 hrs. The flow forecasts are lower than the flow observation which is likely caused by the low estimation of radar rainfall forecasts. The research has well demonstrated that the distributed hydrological model is readily applicable for multisite real-time river flow analysis and forecasting in a large basin.
Dual-EKF-Based Real-Time Celestial Navigation for Lunar Rover
Li Xie
2012-01-01
Full Text Available A key requirement of lunar rover autonomous navigation is to acquire state information accurately in real-time during its motion and set up a gradual parameter-based nonlinear kinematics model for the rover. In this paper, we propose a dual-extended-Kalman-filter- (dual-EKF- based real-time celestial navigation (RCN method. The proposed method considers the rover position and velocity on the lunar surface as the system parameters and establishes a constant velocity (CV model. In addition, the attitude quaternion is considered as the system state, and the quaternion differential equation is established as the state equation, which incorporates the output of angular rate gyroscope. Therefore, the measurement equation can be established with sun direction vector from the sun sensor and speed observation from the speedometer. The gyro continuous output ensures the algorithm real-time operation. Finally, we use the dual-EKF method to solve the system equations. Simulation results show that the proposed method can acquire the rover position and heading information in real time and greatly improve the navigation accuracy. Our method overcomes the disadvantage of the cumulative error in inertial navigation.
Compiling graphical real-time specifications into silicon
Fränzle, Martin; Lüth, Karsten
1998-01-01
The basic algorithms underlying an automatic hardware synthesis environment using fully formal graphical requirements specifications as source language are outlined. The source language is real-time symbolic timing diagrams [FeyerabendJosko97], which are a metric-time temporal logic such that hard...... real-time constraints have to be dealt with. While automata-theoretic methods based on translating the specification to a finite automaton and constructing a winning strategy in the resulting omega-regular game could in principle be used, and do indeed provide the core algorithm, complexity withstands...... practical application of these methods. Therefore, a compositional extension is explored, which yields modular synthesis of multi-component controllers. Based on this, a second extension is proposed for efficiently dealing with hard real-time constraints....
A Real-Time Performance Analysis Model for Cryptographic Protocols
Amos Olagunju
2012-12-01
Full Text Available Several encryption algorithms exist today for securing data in storage and transmission over network systems. The choice of encryption algorithms must weigh performance requirements against the call for protection of sensitive data. This research investigated the processing times of alternative encryption algorithms under specific conditions. The paper presents the architecture of a model multiplatform tool for the evaluation of candidate encryption algorithms based on different data and key sizes. The model software was used to appraise the real-time performance of DES, AES, 3DES, MD5, SHA1, and SHA2 encryption algorithms.
Real Time Eye Template Detection and Tracking
Richa Mehta
2012-06-01
Full Text Available There has been a growing interest in the field of facial expression recognition especially in the last two decades. An example of such a system is the improvement of driver carefulness and accident reduction. The driver’s face is tracked while he is driving and he is warned if there seems to be an alerting fact that can result in an accident such as sleepy eyes, or looking out of the road. Furthermore, with a facial feature tracker, it becomes possible to play a synthesized avatar so that it imitates the expressions of the performer. Human-Computer Interaction (HCI systems may also be enriched by a facial feature tracker. For a user who is incapable of using her hands, a facial expression controller may be a solution to send limited commands to a computer. Eye blinking is one of the prominent areas to solve many real world problems. The process of blink detection consists of two phases. These are eye tracking followed by detection of blink. The work that has been carried out for eye tracking only is not suitable for eye blink detection. Therefore some approaches had been proposed for eye tracking along with eyes blink detection. In this thesis, real time implementation is done to count number of eye blinks in an image sequence. At last after analyzing all these approaches some of the parameters we obtained on which better performance of eye blink detection algorithm depend. This project focuses on automatic eye blink detection in real time. The aim of this thesis is to count the number of eye blinks in a video. This project will be performed on a video database of the facial expressions.
Real-time feedback from iterative electronic structure calculations.
Vaucher, Alain C; Haag, Moritz P; Reiher, Markus
2016-04-05
Real-time feedback from iterative electronic structure calculations requires to mediate between the inherently unpredictable execution times of the iterative algorithm used and the necessity to provide data in fixed and short time intervals for real-time rendering. We introduce the concept of a mediator as a component able to deal with infrequent and unpredictable reference data to generate reliable feedback. In the context of real-time quantum chemistry, the mediator takes the form of a surrogate potential that has the same local shape as the first-principles potential and can be evaluated efficiently to deliver atomic forces as real-time feedback. The surrogate potential is updated continuously by electronic structure calculations and guarantees to provide a reliable response to the operator for any molecular structure. To demonstrate the application of iterative electronic structure methods in real-time reactivity exploration, we implement self-consistent semiempirical methods as the data source and apply the surrogate-potential mediator to deliver reliable real-time feedback.
Geomagnetic Observatory Data for Real-Time Applications
Love, J. J.; Finn, C. A.; Rigler, E. J.; Kelbert, A.; Bedrosian, P.
2015-12-01
The global network of magnetic observatories represents a unique collective asset for the scientific community. Historically, magnetic observatories have supported global magnetic-field mapping projects and fundamental research of the Earth's interior and surrounding space environment. More recently, real-time data streams from magnetic observatories have become an important contributor to multi-sensor, operational monitoring of evolving space weather conditions, especially during magnetic storms. In this context, the U.S. Geological Survey (1) provides real-time observatory data to allied space weather monitoring projects, including those of NOAA, the U.S. Air Force, NASA, several international agencies, and private industry, (2) collaborates with Schlumberger to provide real-time geomagnetic data needed for directional drilling for oil and gas in Alaska, (3) develops products for real-time evaluation of hazards for the electric-power grid industry that are associated with the storm-time induction of geoelectric fields in the Earth's conducting lithosphere. In order to implement strategic priorities established by the USGS Natural Hazards Mission Area and the National Science and Technology Council, and with a focus on developing new real-time products, the USGS is (1) leveraging data management protocols already developed by the USGS Earthquake Program, (2) developing algorithms for mapping geomagnetic activity, a collaboration with NASA and NOAA, (3) supporting magnetotelluric surveys and developing Earth conductivity models, a collaboration with Oregon State University and the NSF's EarthScope Program, (4) studying the use of geomagnetic activity maps and Earth conductivity models for real-time estimation of geoelectric fields, (5) initiating geoelectric monitoring at several observatories, (6) validating real-time estimation algorithms against historical geomagnetic and geoelectric data. The success of these long-term projects is subject to funding constraints
Real-time simulation of thermal shadows with EMIT
Klein, Andreas; Oberhofer, Stefan; Schätz, Peter; Nischwitz, Alfred; Obermeier, Paul
2016-05-01
Modern missile systems use infrared imaging for tracking or target detection algorithms. The development and validation processes of these missile systems need high fidelity simulations capable of stimulating the sensors in real-time with infrared image sequences from a synthetic 3D environment. The Extensible Multispectral Image Generation Toolset (EMIT) is a modular software library developed at MBDA Germany for the generation of physics-based infrared images in real-time. EMIT is able to render radiance images in full 32-bit floating point precision using state of the art computer graphics cards and advanced shader programs. An important functionality of an infrared image generation toolset is the simulation of thermal shadows as these may cause matching errors in tracking algorithms. However, for real-time simulations, such as hardware in the loop simulations (HWIL) of infrared seekers, thermal shadows are often neglected or precomputed as they require a thermal balance calculation in four-dimensions (3D geometry in one-dimensional time up to several hours in the past). In this paper we will show the novel real-time thermal simulation of EMIT. Our thermal simulation is capable of simulating thermal effects in real-time environments, such as thermal shadows resulting from the occlusion of direct and indirect irradiance. We conclude our paper with the practical use of EMIT in a missile HWIL simulation.
Real Time PCR: Principles and Application
Safie Amini
2005-09-01
levels are compared between samples, the expression level of the target is referred to as being, for example, 100-fold higher in stimulated cells than in unstimulated cells. The quantification procedure differs depending on whether the target and the endogenous reference genes are amplified with comparable or different efficiencies(20, 21.Viral QuantificationThe possibility to detect viral DNA or RNA in a quantitative manner has already contributed significantly to the management and diagnosis of viral infections, as well as to the understanding of virus-host interactions. New developments in amplification techniques based on real-time detection, as well as automation of the whole process, will soon be introduced in a diagnostic laboratory setting, thereby enabling a rapid turnaround time to generate both quantitative and qualitative results. The development of molecular techniques that access viral load and the development of genotypic resistance have revolutionized the treatment of HIV disease. Commercially available viral load assays use a number of different approaches from reverse transcriptase PCR to branched DNA signalamplification. The drawbacks of the assay are that there is no international standard that allows comparison of viral load between assays and that the diversity of different clades of HIV results in under or the nondetection of some patients' samples. New real-time PCR assays are under development, including LightCycler- and TaqMan-based tests. The development of sequence-based genotyping assays for the detection of mutations associated with the development of the resistance to the 17 licensed drugs targeted against the pol gene of HIV have added to the improvements in patient management. However, next-generation assays must extend detection to include the gp41 fusion region and the integrase region of the genome as compounds directed against these targets move from clinical trails into licensed drugs. Also, genotypic assays must improve detection of
Real time UAV autonomy through offline calculations
Jung, Sunghun
. Once one or several targets are detected, UAVs near the target are manipulated to approach to the target. If the number of detected targets is more than one, UAVs are evenly grouped to track targets. After a specific period of time, UAVs hand off and continue their original tasks. Thirdly, Emergency algorithm is generated to avoid losses of UAVs when UAVs have system failures. If one UAV is out of fuel or control during the mission, the Emergency algorithm brings the malfunctioning UAV to the point of departure and let the rest UAVs to continue an aerial reconnaissance. An UAV which finishes its task the earliest will continue to search a region which the failed UAV is supposed to search. In addition, Emergency algorithm prevents UAVs colliding into each other by using emergency altitude. Overall, the framework developed here facilitates the solution of several mission planning problems. The robustness built into our discretization of space and time permits feedback corrections on real-time to vehicle trajectories. The library of off-line solutions proposed and developed here minimizes computational overhead during operations.
A real-time method for autonomous passive acoustic detection-classification of humpback whales.
Abbot, Ted A; Premus, Vincent E; Abbot, Philip A
2010-05-01
This paper describes a method for real-time, autonomous, joint detection-classification of humpback whale vocalizations. The approach adapts the spectrogram correlation method used by Mellinger and Clark [J. Acoust. Soc. Am. 107, 3518-3529 (2000)] for bowhead whale endnote detection to the humpback whale problem. The objective is the implementation of a system to determine the presence or absence of humpback whales with passive acoustic methods and to perform this classification with low false alarm rate in real time. Multiple correlation kernels are used due to the diversity of humpback song. The approach also takes advantage of the fact that humpbacks tend to vocalize repeatedly for extended periods of time, and identification is declared only when multiple song units are detected within a fixed time interval. Humpback whale vocalizations from Alaska, Hawaii, and Stellwagen Bank were used to train the algorithm. It was then tested on independent data obtained off Kaena Point, Hawaii in February and March of 2009. Results show that the algorithm successfully classified humpback whales autonomously in real time, with a measured probability of correct classification in excess of 74% and a measured probability of false alarm below 1%.
Particle Swarm Based Approach of a Real-Time Discrete Neural Identifier for Linear Induction Motors
Alma Y. Alanis
2013-01-01
Full Text Available This paper focusses on a discrete-time neural identifier applied to a linear induction motor (LIM model, whose model is assumed to be unknown. This neural identifier is robust in presence of external and internal uncertainties. The proposed scheme is based on a discrete-time recurrent high-order neural network (RHONN trained with a novel algorithm based on extended Kalman filter (EKF and particle swarm optimization (PSO, using an online series-parallel con figuration. Real-time results are included in order to illustrate the applicability of the proposed scheme.
Space Weather and Real-Time Monitoring
2009-01-01
Recent advance of information and communications technology enables to collect a large amount of ground-based and space-based observation data in real-time. The real-time data realize nowcast of space weather. This paper reports a history of space weather by the International Space Environment Service (ISES) in association with the International Geophysical Year (IGY) and importance of real-time monitoring in space weather.
Space Weather and Real-Time Monitoring
S Watari
2009-04-01
Full Text Available Recent advance of information and communications technology enables to collect a large amount of ground-based and space-based observation data in real-time. The real-time data realize nowcast of space weather. This paper reports a history of space weather by the International Space Environment Service (ISES in association with the International Geophysical Year (IGY and importance of real-time monitoring in space weather.
Dendritic Cells for Real-Time Anomaly Detection
Greensmith, Julie
2010-01-01
Dendritic Cells (DCs) are innate immune system cells which have the power to activate or suppress the immune system. The behaviour of human of human DCs is abstracted to form an algorithm suitable for anomaly detection. We test this algorithm on the real-time problem of port scan detection. Our results show a significant difference in artificial DC behaviour for an outgoing portscan when compared to behaviour for normal processes.
Extended Approximate String Matching Algorithms To Detect Name Aliases
Shaikh, Muniba; Memon, Nasrullah; Wiil, Uffe Kock
2011-01-01
. An extension to widely used ASM algorithms is proposed to detect the name aliases that generate as a result of transliteration. This paper aims to improve the accuracy of the basic ASM algorithms in order to detect correct aliases. The experimental evaluation shows that proposed extension increases...
Modeling and Analyzing Adaptive User-Centric Systems in Real-Time Maude
Andreas Schroeder
2010-09-01
Full Text Available Pervasive user-centric applications are systems which are meant to sense the presence, mood, and intentions of users in order to optimize user comfort and performance. Building such applications requires not only state-of-the art techniques from artificial intelligence but also sound software engineering methods for facilitating modular design, runtime adaptation and verification of critical system requirements. In this paper we focus on high-level design and analysis, and use the algebraic rewriting language Real-Time Maude for specifying applications in a real-time setting. We propose a generic component-based approach for modeling pervasive user-centric systems and we show how to analyze and prove crucial properties of the system architecture through model checking and simulation. For proving time-dependent properties we use Metric Temporal Logic (MTL and present analysis algorithms for model checking two subclasses of MTL formulas: time-bounded response and time-bounded safety MTL formulas. The underlying idea is to extend the Real-Time Maude model with suitable clocks, to transform the MTL formulas into LTL formulas over the extended specification, and then to use the LTL model checker of Maude. It is shown that these analyses are sound and complete for maximal time sampling. The approach is illustrated by a simple adaptive advertising scenario in which an adaptive advertisement display can react to actions of the users in front of the display.
Real time process algebra with time-dependent conditions
Baeten, J.C.M.; Middelburg, C.A.
2000-01-01
We extend the main real time version of ACP presented in [6] with conditionals in which the condition depends on time. This extension facilitates flexible dependence of proccess behaviour on initialization time. We show that the conditions concerned generalize the conditions introduced earlier in a
Real time process algebra with time-dependent conditions
Baeten, J.C.M.; Middelburg, C.A.
2008-01-01
We extend the main real time version of ACP presented in [6] with conditionals in which the condition depends on time. This extension facilitates flexible dependence of proccess behaviour on initialization time. We show that the conditions concerned generalize the conditions introduced earlier in a
Real time process algebra with time-dependent conditions
Baeten, J.C.M.; Middelburg, C.A.
We extend the main real time version of ACP presented in [6] with conditionals in which the condition depends on time. This extension facilitates flexible dependence of proccess behaviour on initialization time. We show that the conditions concerned generalize the conditions introduced earlier
Rattlesnake: a network for real-time Multimedia Communication
Smit, Gerard J.M.; Havinga, Paul J.M.; Smit, Michel J.P.
1992-01-01
In this extended abstract we describe the design of a local area network suitable for distributed multimedia communications. Multimedia applications require a communication infrastructure with capabilities beyond the current state of the art : real-time stream traffic, small end-to-end latency with
Rattlesnake: a Network for Real-time Multimedia Communication
Smit, Gerard J.M.; Havinga, Paul J.M.; Smit, Michel J.P.
1992-01-01
In this extended abstract we describe the design of a local area network suitable for distributed multimedia communications. Multimedia applications require a communication infrastructure with capabilities beyond the current state of the art : real-time stream traffic, small end-to-end latency with
Compilation and synthesis for real-time embedded controllers
Fränzle, Martin; Müller-Olm, Markus
1999-01-01
with translation of imperative programs, extended by hard real-time commands which allow one to specify upper bounds for the execution time of basic blocks. In the second approach, Duration Calculus, a metric-time temporal logic, is used as the source language. Duration Calculus allows one to specify real...
Real-time graphics rendering engine
Bao, Hujun
2011-01-01
""Real-Time Graphics Rendering Engine"" reveals the software architecture of the modern real-time 3D graphics rendering engine and the relevant technologies based on the authors' experience developing this high-performance, real-time system. The relevant knowledge about real-time graphics rendering such as the rendering pipeline, the visual appearance and shading and lighting models are also introduced. This book is intended to offer well-founded guidance for researchers and developers who are interested in building their own rendering engines. Hujun Bao is a professor at the State Key Lab of
Real-time Pricing in Power Markets
Boom, Anette; Schwenen, Sebastian
We examine welfare eects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...
Real-time Pricing in Power Markets
Boom, Anette; Schwenen, Sebastian
We examine welfare e ects of real-time pricing in electricity markets. Before stochastic energy demand is known, competitive retailers contract with nal consumers who exogenously do not have real-time meters. After demand is realized, two electricity generators compete in a uniform price auction...... to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...
张明; 王磊; 王硕; 喻慧
2016-01-01
航空器冲突探测和解脱的实时计算对航空救援飞行安全意义重大。基于低空目视飞行规则，构建三维空域网格，采用时间窗理论分析了两航空器同高度飞行的时空冲突判定方法。依据救援目视飞行规则和航空器飞行性能约束，建立航空器 Agent 的可行路径集和基于网格划分的 Airspace模型，并根据航空器 Agent 的救援任务属性确定了优先级判定准则，对各个 Agent 模型在冲突顶点上的优先级进行判定。建立两航空器无冲突最优路径规划方法，计算 Agent 的无冲突路径。通过仿真验证，分析了飞行冲突的时间窗和区域，以及优先级下的无冲突路径，结果表明，本方法相对于非协作的冲突探测和解脱方法可以有效提高解脱效率，节约飞行时间146 s。%Real-time flight conflict detection and resolution algorithm is very important to aviation emergency rescue under the environment of complex low-altitude airspace.Based on low-altitude visual flight rules,this paper constructed a three-dimensional spatial grid,using the time window theory to analyze the temporal and spatial conflict of two flights. Based on visual flight rules during rescue and performance constraints of aircrafts,a feasible path set and Airspace model based on mesh generation for flight Agents are developed.Then priority of each Agent is identified at the conflicting point. Feasible non-conflict paths can be obtained by using the Agent model.Then an optimal path planning method is developed and the paths without any conflicts are created.The results are verified through a simulation,and the time window and the area of flight conflict,and the paths without any conflicts under different priority are analyzed.The results show that this method can provide a higher solution efficiency than non-collaborative methods,which can save a flight time of 146 s.
Terrestrial Real-Time Volcano Monitoring
Franke, M.
2013-12-01
As volcano monitoring involves more and different sensors from seismic to GPS receivers, from video and thermal cameras to multi-parameter probes measuring temperature, ph values and humidity in the ground and the air, it becomes important to design real-time networks that integrate and leverage the multitude of available parameters. In order to do so some simple principles need to be observed: a) a common time base for all measurements, b) a packetized general data communication protocol for acquisition and distribution, c) an open and well documented interface to the data permitting standard and emerging innovative processing, and d) an intuitive visualization platform for scientists and civil defense personnel. Although mentioned as simple principles, the list above does not necessarily lead to obvious solutions or integrated systems, which is, however, required to take advantage of the available data. Only once the different data streams are put into context to each other in terms of time and location can a broader view be obtained and additional information extracted. The presentation is a summary of currently available technologies and how they can achieve the goal of an integrated real-time volcano monitoring system. A common time base are standard for seismic and GPS networks. In different projects we extended this to video feeds and time-lapse photography. Other probes have been integrated with vault interface enclosures (VIE) as used in the Transportable Array (TA) of the USArray. The VIE can accommodate the sensors employed in volcano monitoring. The TA has shown that Antelope is a versatile and robust middleware. It provides the required packetized general communication protocol that is independent from the actual physical communication link leaving the network design to adopt appropriate and possible hybrid solutions. This applies for the data acquisition and the data/information dissemination providing both a much needed collaboration platform, as
Integration of Real-Time Data Into Building Automation Systems
Mark J. Stunder; Perry Sebastian; Brenda A. Chube; Michael D. Koontz
2003-04-16
The project goal was to investigate the possibility of using predictive real-time information from the Internet as an input to building management system algorithms. The objectives were to identify the types of information most valuable to commercial and residential building owners, managers, and system designers. To comprehensively investigate and document currently available electronic real-time information suitable for use in building management systems. Verify the reliability of the information and recommend accreditation methods for data and providers. Assess methodologies to automatically retrieve and utilize the information. Characterize equipment required to implement automated integration. Demonstrate the feasibility and benefits of using the information in building management systems. Identify evolutionary control strategies.
Real time visual tracking of targets in six dimensions
Walsh, Peter M.; Shawaga, Larry
1990-01-01
Six dimensional target information is produced by a target tracking vision system for use in real time target tracking by a robotic system. The vision system described in this paper produces three axes of position data and three axes of orientation data using a single camera which views a three dimensional target. The system performs target detection, target discrimination and determines the target position and orientation relative to the camera. As the target information is determined, it is communicated to a computer which is controlling the robot motion in real time. Details of the image processing algorithms and image processing hardware used in the vision system are discussed in the paper.
Real-time Social Internet Data to Guide Forecasting Models
Del Valle, Sara Y. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-09-20
Our goal is to improve decision support by monitoring and forecasting events using social media, mathematical models, and quantifying model uncertainty. Our approach is real-time, data-driven forecasts with quantified uncertainty: Not just for weather anymore. Information flow from human observations of events through an Internet system and classification algorithms is used to produce quantitatively uncertain forecast. In summary, we want to develop new tools to extract useful information from Internet data streams, develop new approaches to assimilate real-time information into predictive models, validate approaches by forecasting events, and our ultimate goal is to develop an event forecasting system using mathematical approaches and heterogeneous data streams.
A heterogeneous hierarchical architecture for real-time computing
Skroch, D.A.; Fornaro, R.J.
1988-12-01
The need for high-speed data acquisition and control algorithms has prompted continued research in the area of multiprocessor systems and related programming techniques. The result presented here is a unique hardware and software architecture for high-speed real-time computer systems. The implementation of a prototype of this architecture has required the integration of architecture, operating systems and programming languages into a cohesive unit. This report describes a Heterogeneous Hierarchial Architecture for Real-Time (H{sup 2} ART) and system software for program loading and interprocessor communication.
Real time microcontroller implementation of an adaptive myoelectric filter.
Bagwell, P J; Chappell, P H
1995-03-01
This paper describes a real time digital adaptive filter for processing myoelectric signals. The filter time constant is automatically selected by the adaptation algorithm, giving a significant improvement over linear filters for estimating the muscle force and controlling a prosthetic device. Interference from mains sources often produces problems for myoelectric processing, and so 50 Hz and all harmonic frequencies are reduced by an averaging filter and differential process. This makes practical electrode placement and contact less critical and time consuming. An economic real time implementation is essential for a prosthetic controller, and this is achieved using an Intel 80C196KC microcontroller.
Paul, Rourab; Sau, Suman; Chakrabarti, Amlan
2012-01-01
Security is the most important part in data communication system, where more randomization in secret keys increases the security as well as complexity of the cryptography algorithms. As a result in recent dates these algorithms are compensating with enormous memory spaces and large execution time on hardware platform. Field programmable gate arrays (FPGAs), provide one of the major alternative in hardware platform scenario due to its reconfiguration nature, low price and marketing speed. In FPGA based embedded system we can use embedded processor to execute particular algorithm with the inclusion of a real time operating System (RTOS), where threads may reduce resource utilization and time consumption. A process in the runtime is separated in different smaller tasks which are executed by the scheduler to meet the real time dead line using RTOS. In this paper we demonstrate the design and implementation of a 128-bit Advanced Encryption Standard (AES) both symmetric key encryption and decryption algorithm by de...
Haag, Moritz P
2012-01-01
Significant progress in the development of efficient and fast algorithms for quantum chemical calculations has been made in the past two decades. The main focus has always been the desire to be able to treat ever larger molecules or molecular assemblies---especially linear and sub-linear scaling techniques are devoted to the accomplishment of this goal. However, as many chemical reactions are rather local, they usually involve only a limited number of atoms so that models of about two hundred (or even less) atoms embedded in a suitable environment are sufficient to study their mechanisms. Thus, the system size does not need to be enlarged, but remains constant for reactions of this type that can be described by less than two hundred atoms. The question then arises how fast one can obtain the quantum chemical results. This question is not directly answered by linear-scaling techniques. In fact, ideas such as haptic quantum chemistry or interactive quantum chemistry require an immediate provision of quantum che...
A Theory for the Initial Allocating of Real Time Tasks in Distributed Systems
鄢勇; 金灿明
1992-01-01
Referring to a set of real time tasks with arriving time,executing time and deadline,this paper discusses the problem of polynomial time initial-allocating approximation algorithms in a distributed system and five new results are gained which provide a theory for the designing of initial-allocating algorithms of real time tasks.
Qiguang Zhu
2014-05-01
Full Text Available To resolve the difficulty in establishing accurate priori noise model for the extended Kalman filtering algorithm, propose the fractional-order Darwinian particle swarm optimization (PSO algorithm has been proposed and introduced into the fuzzy adaptive extended Kalman filtering algorithm. The natural selection method has been adopted to improve the standard particle swarm optimization algorithm, which enhanced the diversity of particles and avoided the premature. In addition, the fractional calculus has been used to improve the evolution speed of particles. The PSO algorithm after improved has been applied to train fuzzy adaptive extended Kalman filter and achieve the simultaneous localization and mapping. The simulation results have shown that compared with the geese particle swarm optimization training of fuzzy adaptive extended Kalman filter localization and mapping algorithm, has been greatly improved in terms of localization and mapping.
Hardware Approach for Real Time Machine Stereo Vision
Michael Tornow
2006-02-01
Full Text Available Image processing is an effective tool for the analysis of optical sensor information for driver assistance systems and controlling of autonomous robots. Algorithms for image processing are often very complex and costly in terms of computation. In robotics and driver assistance systems, real-time processing is necessary. Signal processing algorithms must often be drastically modified so they can be implemented in the hardware. This task is especially difficult for continuous real-time processing at high speeds. This article describes a hardware-software co-design for a multi-object position sensor based on a stereophotogrammetric measuring method. In order to cover a large measuring area, an optimized algorithm based on an image pyramid is implemented in an FPGA as a parallel hardware solution for depth map calculation. Object recognition and tracking are then executed in real-time in a processor with help of software. For this task a statistical cluster method is used. Stabilization of the tracking is realized through use of a Kalman filter. Keywords: stereophotogrammetry, hardware-software co-design, FPGA, 3-d image analysis, real-time, clustering and tracking.
Structural Analysis Extended with Active Fault Isolation - Methods and Algorithms
Gelso, Esteban R.; Blanke, Mogens
2009-01-01
on system inputs can considerably enhance fault isolability. This paper investigates this possibility of active fault isolation from a structural point of view. While such extension of the structural analysis approach was suggested earlier, algorithms and case studies were needed to explore this theory....... The paper develops algorithms for investigation of the possibilities of active structural isolation and it offers illustrative examples and a larger case study to explore the properties of active structural isolability ideas....
Collaborative Methods for Real-time Localization in Urban Centers
Sébastien Peyraud
2015-11-01
Full Text Available This article presents an effective solution for the localization of a vehicle in dense urban areas where GNSS-based methods fail because of poor satellite visibility. It advocates the use of a visual-based method processing georeferenced landmarks obtained after a learning path and stored in a new layer of the geographical information system (GIS used for navigation. Real-time localization gives, with few failures, accurate results in the areas covered by the GIS. The integrity of the localization is obtained by running another algorithm in parallel, processing odometric data combined with the geometric model of the drivable area and, when available, GNSS data in tight coupling. An ellipsoidal confidence domain is updated by using both extended Kalman filtering (EKF and set-membership estimation. Although less accurate, this estimation is reliable and, when the visual method fails, the availability of a confidence domain enables us to speed up the restart of the visual method while navigating cautiously. A large-scale experiment (>4 km was conducted in the centre of Paris. We compare the absolute localization results with the ground truth obtained by combining RTK-GPS and a high-end inertial measurement unit (IMU.
Improved algorithms for approximate string matching (extended abstract
Papamichail Georgios
2009-01-01
Full Text Available Abstract Background The problem of approximate string matching is important in many different areas such as computational biology, text processing and pattern recognition. A great effort has been made to design efficient algorithms addressing several variants of the problem, including comparison of two strings, approximate pattern identification in a string or calculation of the longest common subsequence that two strings share. Results We designed an output sensitive algorithm solving the edit distance problem between two strings of lengths n and m respectively in time O((s - |n - m|·min(m, n, s + m + n and linear space, where s is the edit distance between the two strings. This worst-case time bound sets the quadratic factor of the algorithm independent of the longest string length and improves existing theoretical bounds for this problem. The implementation of our algorithm also excels in practice, especially in cases where the two strings compared differ significantly in length. Conclusion We have provided the design, analysis and implementation of a new algorithm for calculating the edit distance of two strings with both theoretical and practical implications. Source code of our algorithm is available online.
Marques, Haroldo; Monico, João; Aquino, Marcio; Melo, Weyller
2014-05-01
that the phase ambiguities are eliminated when applying differences between consecutive epochs. However, when using undifferenced code and phase, the ambiguities may be estimated together with receiver clock errors, satellite clock corrections and troposphere parameters. In both strategies it is also possible to correct the troposphere delay from a Numerical Weather Forecast Model instead of estimating it. The prediction of the satellite clock correction can be performed using a straight line or a second degree polynomial using the time series of the estimated satellites clocks. To estimate satellite clock correction and to accomplish real time PPP two pieces of software have been developed, respectively, "RT_PPP" and "RT_SAT_CLOCK". The system (RT_PPP) is able to process GNSS code and phase data using precise ephemeris and precise satellites clocks corrections together with several corrections required for PPP. In the software RT_SAT_CLOCK we apply a Kalman filter algorithm to estimate satellite clock correction in the network PPP mode. In this case, all PPP corrections must be applied for each station. The experiments were generated in real time and post-processed mode (simulating real time) considering data from the Brazilian continuous GPS network and also from the IGS network in a global satellite clock solution. We have used IGU ephemeris for satellite position and estimated the satellite clock corrections, performing the updates as soon as new ephemeris files were available. Experiments were accomplished in order to assess the accuracy of the estimated clocks when using the Brazilian Numerical Weather Forecast Model (BNWFM) from CPTEC/INPE and also using the ZTD from European Centre for Medium-Range Weather Forecasts (ECMWF) together with Vienna Mapping Function VMF or estimating troposphere with clocks and ambiguities in the Kalman Filter. The daily precision of the estimated satellite clock corrections reached the order of 0.15 nanoseconds. The clocks were
Real-time progressive hyperspectral image processing endmember finding and anomaly detection
Chang, Chein-I
2016-01-01
The book covers the most crucial parts of real-time hyperspectral image processing: causality and real-time capability. Recently, two new concepts of real time hyperspectral image processing, Progressive Hyperspectral Imaging (PHSI) and Recursive Hyperspectral Imaging (RHSI). Both of these can be used to design algorithms and also form an integral part of real time hyperpsectral image processing. This book focuses on progressive nature in algorithms on their real-time and causal processing implementation in two major applications, endmember finding and anomaly detection, both of which are fundamental tasks in hyperspectral imaging but generally not encountered in multispectral imaging. This book is written to particularly address PHSI in real time processing, while a book, Recursive Hyperspectral Sample and Band Processing: Algorithm Architecture and Implementation (Springer 2016) can be considered as its companion book. Includes preliminary background which is essential to those who work in hyperspectral ima...
Tokamak equilibrium reconstruction code LIUQE and its real time implementation
Moret, J.-M., E-mail: jean-marc.moret@epfl.ch; Duval, B.P.; Le, H.B.; Coda, S.; Felici, F.; Reimerdes, H.
2015-02-15
Highlights: • Algorithm vertical stabilisation using a linear parametrisation of the current density. • Experimentally derived model of the vacuum vessel to account for vessel currents. • Real-time contouring algorithm for flux surface averaged 1.5 D transport equations. • Full real time implementation coded in SIMULINK runs in less than 200 μs. • Applications: shape control, safety factor profile control, coupling with RAPTOR. - Abstract: Equilibrium reconstruction consists in identifying, from experimental measurements, a distribution of the plasma current density that satisfies the pressure balance constraint. The LIUQE code adopts a computationally efficient method to solve this problem, based on an iterative solution of the Poisson equation coupled with a linear parametrisation of the plasma current density. This algorithm is unstable against vertical gross motion of the plasma column for elongated shapes and its application to highly shaped plasmas on TCV requires a particular treatment of this instability. TCV's continuous vacuum vessel has a low resistance designed to enhance passive stabilisation of the vertical position. The eddy currents in the vacuum vessel have a sizeable influence on the equilibrium reconstruction and must be taken into account. A real time version of LIUQE has been implemented on TCV's distributed digital control system with a cycle time shorter than 200 μs for a full spatial grid of 28 by 65, using all 133 experimental measurements and including the flux surface average of quantities necessary for the real time solution of 1.5 D transport equations. This performance was achieved through a thoughtful choice of numerical methods and code optimisation techniques at every step of the algorithm, and was coded in MATLAB and SIMULINK for the off-line and real time version respectively.
Explaining How to Play Real-Time Strategy Games
Metoyer, Ronald; Stumpf, Simone; Neumann, Christoph; Dodge, Jonathan; Cao, Jill; Schnabel, Aaron
Real-time strategy games share many aspects with real situations in domains such as battle planning, air traffic control, and emergency response team management which makes them appealing test-beds for Artificial Intelligence (AI) and machine learning. End user annotations could help to provide supplemental information for learning algorithms, especially when training data is sparse. This paper presents a formative study to uncover how experienced users explain game play in real-time strategy games. We report the results of our analysis of explanations and discuss their characteristics that could support the design of systems for use by experienced real-time strategy game users in specifying or annotating strategy-oriented behavior.
Real-Time Parameter Estimation Using Output Error
Grauer, Jared A.
2014-01-01
Output-error parameter estimation, normally a post- ight batch technique, was applied to real-time dynamic modeling problems. Variations on the traditional algorithm were investigated with the goal of making the method suitable for operation in real time. Im- plementation recommendations are given that are dependent on the modeling problem of interest. Application to ight test data showed that accurate parameter estimates and un- certainties for the short-period dynamics model were available every 2 s using time domain data, or every 3 s using frequency domain data. The data compatibility problem was also solved in real time, providing corrected sensor measurements every 4 s. If uncertainty corrections for colored residuals are omitted, this rate can be increased to every 0.5 s.
Reduction Methods for Real-time Simulations in Hybrid Testing
Andersen, Sebastian
2016-01-01
Hybrid testing constitutes a cost-effective experimental full scale testing method. The method was introduced in the 1960's by Japanese researchers, as an alternative to conventional full scale testing and small scale material testing, such as shake table tests. The principle of the method...... is to divide a structure into a physical substructure and a numerical substructure, and couple these in a test. If the test is conducted in real-time it is referred to as real time hybrid testing. The hybrid testing concept has developed significantly since its introduction in the 1960', both with respect...... without introducing further unknowns into the system. The basis formulation is shown to exhibit high precision and to reduce the computational cost significantly. Furthermore, the basis formulation exhibits a significant higher stability, than standard nonlinear algorithms. A real-time hybrid test...
An optimal real-time controller for vertical plasma stabilization
Cruz, N; Coda, S; Duval, B P; Le, H B; Rodrigues, A P; Varandas, C A F; Correia, C M B A; Goncalves, B S
2014-01-01
Modern Tokamaks have evolved from the initial axisymmetric circular plasma shape to an elongated axisymmetric plasma shape that improves the energy confinement time and the triple product, which is a generally used figure of merit for the conditions needed for fusion reactor performance. However, the elongated plasma cross section introduces a vertical instability that demands a real-time feedback control loop to stabilize the plasma vertical position and velocity. At the Tokamak \\`a Configuration Variable (TCV) in-vessel poloidal field coils driven by fast switching power supplies are used to stabilize highly elongated plasmas. TCV plasma experiments have used a PID algorithm based controller to correct the plasma vertical position. In late 2013 experiments a new optimal real-time controller was tested improving the stability of the plasma. This contribution describes the new optimal real-time controller developed. The choice of the model that describes the plasma response to the actuators is discussed. The ...
Real-time DIRCM system modeling
Petersson, Mikael
2004-12-01
Directed infrared countermeasures (DIRCM) play an increasingly important role in electronic warfare to counteract threats posed by infrared seekers. The usefulness and performance of such countermeasures depend, for example, on atmospheric conditions (attenuation and turbulence) and platform vibrations, causing pointing and tracking errors for the laser beam and reducing the power transferred to the seeker aperture. These problems make it interesting to simulate the performance of a DIRCM system in order to understand how easy or difficult it is to counteract an approaching threat and evaluate limiting factors in various situations. This paper describes a DIRCM model that has been developed, including atmospheric effects such as attenuation and turbulence as well as closed loop tracking algorithms, where the retro reflex of the laser is used for the pointing control of the beam. The DIRCM model is part of a large simulation framework (EWSim), which also incorporates several descriptions of different seekers (e.g. reticle, rosette, centroid, nutating cross) and models of robot dynamics. Effects of a jamming laser on a specific threat can be readily verified by simulations within this framework. The duel between missile and countermeasure is simulated in near real-time and visualized graphically in 3D. A typical simulation with a reticle seeker jammed by a modulated laser is included in the paper.
Real-Time Principal-Component Analysis
Duong, Vu; Duong, Tuan
2005-01-01
A recently written computer program implements dominant-element-based gradient descent and dynamic initial learning rate (DOGEDYN), which was described in Method of Real-Time Principal-Component Analysis (NPO-40034) NASA Tech Briefs, Vol. 29, No. 1 (January 2005), page 59. To recapitulate: DOGEDYN is a method of sequential principal-component analysis (PCA) suitable for such applications as data compression and extraction of features from sets of data. In DOGEDYN, input data are represented as a sequence of vectors acquired at sampling times. The learning algorithm in DOGEDYN involves sequential extraction of principal vectors by means of a gradient descent in which only the dominant element is used at each iteration. Each iteration includes updating of elements of a weight matrix by amounts proportional to a dynamic initial learning rate chosen to increase the rate of convergence by compensating for the energy lost through the previous extraction of principal components. In comparison with a prior method of gradient-descent-based sequential PCA, DOGEDYN involves less computation and offers a greater rate of learning convergence. The sequential DOGEDYN computations require less memory than would parallel computations for the same purpose. The DOGEDYN software can be executed on a personal computer.
Robustness Results for Hierarchical Diff-EDF Scheduling upon Heterogeneous Real-Time Packet Networks
Moutaz Saleh
2007-01-01
Full Text Available Packet networks are currently enabling the integration of traffic with a wide range of characteristics that extend from video traffic with stringent QoS requirements to the best-effort traffic requiring no guarantees. QoS guarantees can be provided in conventional packet networks by the use of proper packet scheduling algorithms. As a computer revolution, many scheduling algorithms have been proposed to provide different schemes of QoS guarantees with Earliest Deadline First (EDF as the most popular one. With EDF scheduling, all flows receive the same miss rate regardless of their traffic characteristics and deadlines. This makes the standard EDF algorithm unsuitable for situations in which the different flows have different miss rate requirements since in order to meet all miss rate requirements it is necessary to limit admissions so as to satisfy the flow with the most stringent miss rate requirements. In this study, we propose a new priority assignment scheduling algorithm, Hierarchal Diff-EDF (Differentiate Earliest Deadline First, which can meet the real-time needs of these applications while continuing to provide best effort service to non-real time traffic. The Hierarchal Diff-EDF features a feedback control mechanism that detects overload conditions and modifies packet priority assignments accordingly.
Computation Offloading for Frame-Based Real-Time Tasks under Given Server Response Time Guarantees
Anas S. M. Toma
2014-11-01
Full Text Available Computation offloading has been adopted to improve the performance of embedded systems by offloading the computation of some tasks, especially computation-intensive tasks, to servers or clouds. This paper explores computation offloading for real-time tasks in embedded systems, provided given response time guarantees from the servers, to decide which tasks should be offloaded to get the results in time. We consider frame-based real-time tasks with the same period and relative deadline. When the execution order of the tasks is given, the problem can be solved in linear time. However, when the execution order is not specified, we prove that the problem is NP-complete. We develop a pseudo-polynomial-time algorithm for deriving feasible schedules, if they exist. An approximation scheme is also developed to trade the error made from the algorithm and the complexity. Our algorithms are extended to minimize the period/relative deadline of the tasks for performance maximization. The algorithms are evaluated with a case study for a surveillance system and synthesized benchmarks.
Storm real-time processing cookbook
Anderson, Quinton
2013-01-01
A Cookbook with plenty of practical recipes for different uses of Storm.If you are a Java developer with basic knowledge of real-time processing and would like to learn Storm to process unbounded streams of data in real time, then this book is for you.
Interactive Real-time Magnetic Resonance Imaging
Brix, Lau
Real-time acquisition, reconstruction and interactively changing the slice position using magnetic resonance imaging (MRI) have been possible for years. However, the current clinical use of interactive real-time MRI is limited due to an inherent low spatial and temporal resolution. This PhD proje...
Validation of RNAi by real time PCR
Josefsen, Knud; Lee, Ying Chiu
2011-01-01
Real time PCR is the analytic tool of choice for quantification of gene expression, while RNAi is concerned with downregulation of gene expression. Together, they constitute a powerful approach in any loss of function studies of selective genes. We illustrate here the use of real time PCR to veri...
Real-time communication protocols: an overview
Hanssen, Ferdy; Jansen, Pierre G.
2003-01-01
This paper describes several existing data link layer protocols that provide real-time capabilities on wired networks, focusing on token-ring and Carrier Sense Multiple Access based networks. Existing modifications to provide better real-time capabilities and performance are also described. Finally
Real-time communication protocols: an overview
Hanssen, Ferdy; Jansen, Pierre G.
2003-01-01
This paper describes several existing data link layer protocols that provide real-time capabilities on wired networks, focusing on token-ring and Carrier Sense Multiple Access based networks. Existing modifications to provide better real-time capabilities and performance are also described. Finally the pros and cons regarding the At-Home Anywhere project are discussed.
Real-time Pricing in Power Markets
Boom, Anette; Schwenen, Sebastian
to satisfy demand from retailers acting on behalf of subscribed customers and from consumers with real-time meters. Increasing the number of consumers on real-time pricing does not always increase welfare since risk-averse consumers dislike uncertain and high prices arising through market power...
Interactive Real-time Magnetic Resonance Imaging
Brix, Lau
Real-time acquisition, reconstruction and interactively changing the slice position using magnetic resonance imaging (MRI) have been possible for years. However, the current clinical use of interactive real-time MRI is limited due to an inherent low spatial and temporal resolution. This PhD proje...
T-L Plane Abstraction-Based Energy-Efficient Real-Time Scheduling for Multi-Core Wireless Sensors.
Kim, Youngmin; Lee, Ki-Seong; Pham, Ngoc-Son; Lee, Sun-Ro; Lee, Chan-Gun
2016-07-08
Energy efficiency is considered as a critical requirement for wireless sensor networks. As more wireless sensor nodes are equipped with multi-cores, there are emerging needs for energy-efficient real-time scheduling algorithms. The T-L plane-based scheme is known to be an optimal global scheduling technique for periodic real-time tasks on multi-cores. Unfortunately, there has been a scarcity of studies on extending T-L plane-based scheduling algorithms to exploit energy-saving techniques. In this paper, we propose a new T-L plane-based algorithm enabling energy-efficient real-time scheduling on multi-core sensor nodes with dynamic power management (DPM). Our approach addresses the overhead of processor mode transitions and reduces fragmentations of the idle time, which are inherent in T-L plane-based algorithms. Our experimental results show the effectiveness of the proposed algorithm compared to other energy-aware scheduling methods on T-L plane abstraction.
Real-time flood extent maps based on social media
Eilander, Dirk; van Loenen, Arnejan; Roskam, Ruud; Wagemaker, Jurjen
2015-04-01
During a flood event it is often difficult to get accurate information about the flood extent and the people affected. This information is very important for disaster risk reduction management and crisis relief organizations. In the post flood phase, information about the flood extent is needed for damage estimation and calibrating hydrodynamic models. Currently, flood extent maps are derived from a few sources such as satellite images, areal images and post-flooding flood marks. However, getting accurate real-time or maximum flood extent maps remains difficult. With the rise of social media, we now have a new source of information with large numbers of observations. In the city of Jakarta, Indonesia, the intensity of unique flood related tweets during a flood event, peaked at 8 tweets per second during floods in early 2014. A fair amount of these tweets also contains observations of water depth and location. Our hypothesis is that based on the large numbers of tweets it is possible to generate real-time flood extent maps. In this study we use tweets from the city of Jakarta, Indonesia, to generate these flood extent maps. The data-mining procedure looks for tweets with a mention of 'banjir', the Bahasa Indonesia word for flood. It then removes modified and retweeted messages in order to keep unique tweets only. Since tweets are not always sent directly from the location of observation, the geotag in the tweets is unreliable. We therefore extract location information using mentions of names of neighborhoods and points of interest. Finally, where encountered, a mention of a length measure is extracted as water depth. These tweets containing a location reference and a water level are considered to be flood observations. The strength of this method is that it can easily be extended to other regions and languages. Based on the intensity of tweets in Jakarta during a flood event we can provide a rough estimate of the flood extent. To provide more accurate flood extend
Real-Time DMB Video Encryption in Recording on PMP
Seong-Yeon Lee
2009-03-01
Full Text Available At July 2008, the nationwide DMB (Digital Multimedia Broadcasting has got started. As DMB device's volume of sales has been over 12 million already, the development of rapidly changing network systems has increased the dangers of infringing the copyright of DMB contents. For solving this problem, we suggest that real-time encryption algorithm without additional expenses, and implemented that on PMP. We used the SEED algorithm for encryption. As the experimental result, we confirmed that the real-time encryption and decryption of DMB videos were working well. Also confirmed that recorded contents in PMP were not replayed in other devices, and also the contents recorded by other devices were not played in PMP. Suggested algorithms can be useful in the VOD, IPTV or cable TV.
GPU-based real-time trinocular stereo vision
Yao, Yuanbin; Linton, R. J.; Padir, Taskin
2013-01-01
Most stereovision applications are binocular which uses information from a 2-camera array to perform stereo matching and compute the depth image. Trinocular stereovision with a 3-camera array has been proved to provide higher accuracy in stereo matching which could benefit applications like distance finding, object recognition, and detection. This paper presents a real-time stereovision algorithm implemented on a GPGPU (General-purpose graphics processing unit) using a trinocular stereovision camera array. Algorithm employs a winner-take-all method applied to perform fusion of disparities in different directions following various image processing techniques to obtain the depth information. The goal of the algorithm is to achieve real-time processing speed with the help of a GPGPU involving the use of Open Source Computer Vision Library (OpenCV) in C++ and NVidia CUDA GPGPU Solution. The results are compared in accuracy and speed to verify the improvement.
Extended seizure detection algorithm for intracranial EEG recordings
Kjaer, T. W.; Remvig, L. S.; Henriksen, J.
2010-01-01
Objective: We implemented and tested an existing seizure detection algorithm for scalp EEG (sEEG) with the purpose of improving it to intracranial EEG (iEEG) recordings. Method: iEEG was obtained from 16 patients with focal epilepsy undergoing work up for resective epilepsy surgery. Each patient...... had 4 or 5 recorded seizures and 24 hours of non-ictal data were used for evaluation. Data from three electrodes placed at the ictal focus were used for the analysis. A wavelet based feature extraction algorithm delivered input to a support vector machine (SVM) classifier for distinction between ictal...... the original implementation a sensitivity of 92.8% and a false positive ratio (FPR) of 0.93/h were obtained. Our extension of the algorithm rendered a 95.9% sensitivity and only 0.65 false detections per hour. Conclusion: Better seizure detection can be performed when the higher frequencies in the iEEG were...
RTMOD: Real-Time MODel evaluation
Graziani, G; Galmarini, S. [Joint Research centre, Ispra (Italy); Mikkelsen, T. [Risoe National Lab., Wind Energy and Atmospheric Physics Dept. (Denmark)
2000-01-01
The 1998 - 1999 RTMOD project is a system based on an automated statistical evaluation for the inter-comparison of real-time forecasts produced by long-range atmospheric dispersion models for national nuclear emergency predictions of cross-boundary consequences. The background of RTMOD was the 1994 ETEX project that involved about 50 models run in several Institutes around the world to simulate two real tracer releases involving a large part of the European territory. In the preliminary phase of ETEX, three dry runs (i.e. simulations in real-time of fictitious releases) were carried out. At that time, the World Wide Web was not available to all the exercise participants, and plume predictions were therefore submitted to JRC-Ispra by fax and regular mail for subsequent processing. The rapid development of the World Wide Web in the second half of the nineties, together with the experience gained during the ETEX exercises suggested the development of this project. RTMOD featured a web-based user-friendly interface for data submission and an interactive program module for displaying, intercomparison and analysis of the forecasts. RTMOD has focussed on model intercomparison of concentration predictions at the nodes of a regular grid with 0.5 degrees of resolution both in latitude and in longitude, the domain grid extending from 5W to 40E and 40N to 65N. Hypothetical releases were notified around the world to the 28 model forecasters via the web on a one-day warning in advance. They then accessed the RTMOD web page for detailed information on the actual release, and as soon as possible they then uploaded their predictions to the RTMOD server and could soon after start their inter-comparison analysis with other modelers. When additional forecast data arrived, already existing statistical results would be recalculated to include the influence by all available predictions. The new web-based RTMOD concept has proven useful as a practical decision-making tool for realtime
Xin Li
2016-02-01
Full Text Available Wireless signal strength is susceptible to the phenomena of interference, jumping, and instability, which often appear in the positioning results based on Wi-Fi field strength fingerprint database technology for indoor positioning. Therefore, a Wi-Fi and PDR (pedestrian dead reckoning real-time fusion scheme is proposed in this paper to perform fusing calculation by adaptively determining the dynamic noise of a filtering system according to pedestrian movement (straight or turning, which can effectively restrain the jumping or accumulation phenomena of wireless positioning and the PDR error accumulation problem. Wi-Fi fingerprint matching typically requires a quite high computational burden: To reduce the computational complexity of this step, the affinity propagation clustering algorithm is adopted to cluster the fingerprint database and integrate the information of the position domain and signal domain of respective points. An experiment performed in a fourth-floor corridor at the School of Environment and Spatial Informatics, China University of Mining and Technology, shows that the traverse points of the clustered positioning system decrease by 65%–80%, which greatly improves the time efficiency. In terms of positioning accuracy, the average error is 4.09 m through the Wi-Fi positioning method. However, the positioning error can be reduced to 2.32 m after integration of the PDR algorithm with the adaptive noise extended Kalman filter (EKF.
Transient imaging for real-time tracking around a corner
Klein, Jonathan; Laurenzis, Martin; Hullin, Matthias
2016-10-01
Non-line-of-sight imaging is a fascinating emerging area of research and expected to have an impact in numerous application fields including civilian and military sensing. Performance of human perception and situational awareness can be extended by the sensing of shapes and movement around a corner in future scenarios. Rather than seeing through obstacles directly, non-line-of-sight imaging relies on analyzing indirect reflections of light that traveled around the obstacle. In previous work, transient imaging was established as the key mechanic to enable the extraction of useful information from such reflections. So far, a number of different approaches based on transient imaging have been proposed, with back projection being the most prominent one. Different hardware setups were used for the acquisition of the required data, however all of them have severe drawbacks such as limited image quality, long capture time or very high prices. In this paper we propose the analysis of synthetic transient renderings to gain more insights into the transient light transport. With this simulated data, we are no longer bound to the imperfect data of real systems and gain more flexibility and control over the analysis. In a second part, we use the insights of our analysis to formulate a novel reconstruction algorithm. It uses an adapted light simulation to formulate an inverse problem which is solved in an analysis-by-synthesis fashion. Through rigorous optimization of the reconstruction, it then becomes possible to track known objects outside the line of side in real time. Due to the forward formulation of the light transport, the algorithm is easily expandable to more general scenarios or different hardware setups. We therefore expect it to become a viable alternative to the classic back projection approach in the future.
Learning in Real-Time Search: A Unifying Framework
Bulitko, V; 10.1613/jair.1789
2011-01-01
Real-time search methods are suited for tasks in which the agent is interacting with an initially unknown environment in real time. In such simultaneous planning and learning problems, the agent has to select its actions in a limited amount of time, while sensing only a local part of the environment centered at the agents current location. Real-time heuristic search agents select actions using a limited lookahead search and evaluating the frontier states with a heuristic function. Over repeated experiences, they refine heuristic values of states to avoid infinite loops and to converge to better solutions. The wide spread of such settings in autonomous software and hardware agents has led to an explosion of real-time search algorithms over the last two decades. Not only is a potential user confronted with a hodgepodge of algorithms, but he also faces the choice of control parameters they use. In this paper we address both problems. The first contribution is an introduction of a simple three-parameter framework...
Real-time change detection in data streams with FPGAs
Vega, J., E-mail: jesus.vega@ciemat.es [Asociación EURATOM/CIEMAT para Fusión, Avda. Complutense, 22, 28040 Madrid (Spain); Dormido-Canto, S.; Cruz, T. [Departamento de Informática y Automática, UNED, Madrid (Spain); Ruiz, M.; Barrera, E. [Grupo de Investigación en Instrumentación y Acústica Aplicada, Universidad Politécnica de Madrid, Madrid (Spain); Castro, R. [Asociación EURATOM/CIEMAT para Fusión, Avda. Complutense, 22, 28040 Madrid (Spain); Murari, A. [Associazione EURATOM-ENEA per la Fusione, Consorzio RFX, I-35127 Padova (Italy); Ochando, M. [Asociación EURATOM/CIEMAT para Fusión, Avda. Complutense, 22, 28040 Madrid (Spain)
2014-05-15
Highlights: • Automatic recognition of changes in data streams of multidimensional signals. • Detection algorithm based on testing exchangeability on-line. • Real-time and off-line applicability. • Real-time implementation in FPGAs. - Abstract: The automatic recognition of changes in data streams is useful in both real-time and off-line data analyses. This article shows several effective change-detecting algorithms (based on martingales) and describes their real-time applicability in the data acquisition systems through the use of Field Programmable Gate Arrays (FPGA). The automatic event recognition system is absolutely general and it does not depend on either the particular event to detect or the specific data representation (waveforms, images or multidimensional signals). The developed approach provides good results for change detection in both the temporal evolution of profiles and the two-dimensional spatial distribution of volume emission intensity. The average computation time in the FPGA is 210 μs per profile.
Real time n/γ discrimination for the JET neutron profile monitor
Riva, M., E-mail: marco.riva@enea.it [Associazione EURATOM-ENEA sulla Fusione, C.P. 65, Frascati I-00044, Roma (Italy); Esposito, B.; Marocco, D.; Belli, F. [Associazione EURATOM-ENEA sulla Fusione, C.P. 65, Frascati I-00044, Roma (Italy); Syme, B. [EURATOM/CCFE Fusion Association, OX14 3DB Abingdon (United Kingdom); Giacomelli, L. [Dipartimento di Fisica, Università degli Studi di Milano-Bicocca (Italy); Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, 20100 Milano (Italy); JET-EFDA, Culham Science Centre, OX14 3DB Abingdon (United Kingdom)
2013-10-15
Highlights: ► Development of a pulse oriented acquisition system able for the JET neutron profile monitor to separate neutron and gamma pulses. ► Description of the FPGA hardware architecture. ► Comparison between the off-line and real time neutron count rates from the last JET experimental campaign. ► Estimate of the maximum sustainable count rate of the system. ► Statistical analysis of neutron measurements from JET neutron profile monitor and neutron monitors. -- Abstract: The JET neutron profile monitor provides the measurement of the neutron flux along 19 collimated lines of sight from which the neutron emissivity profile can be obtained through reconstruction based on inversion methods. The neutron detectors are liquid organic scintillators featuring n/γ pulse shape discrimination. A recent digital upgrade of the neutron profile monitor acquisition system (200 MSamples/s sampling rate per channel, 14 bit resolution) offers new real-time capabilities. An algorithm performing real-time n/γ discrimination by means of the charge comparison method is implemented in the acquisition system FPGA. The algorithm produces two distinct count rates (n and γ) that are sent to the JET real time network ready for control applications and are simultaneously stored into the JET archive together with all the samples of each pulse. The paper describes the architecture of the FPGA implementation and reports the analysis of data collected during the 2011–2012 JET campaigns. The comparison between the real-time and post-processed (off-line) neutron count rates shows an agreement within 5% for all 19 detectors. Moreover, it is shown that the maximum count rate sustainable by the acquisition system when storing raw data (∼900 kHz as evaluated in laboratory tests) can be extended up to 5 MHz when using the real-time implementation with no local data storage. Finally, a statistical analysis of the ratio between the line-integrated measurements from the neutron profile
苏礼楷
2011-01-01
The real-time flow of customer data changed with time is classified as the time series. According to the receiving frequency , the relational model is applied for the storage of the customer data. In order to weaken the influence of the query efficiency of the real-time customer-counting by the receiving frequency, the views of the customer data with multiple time granularities are established and the query efficiency is improved.%随时间实时变化的客流数据属于时间序列数据,本文根据客流数据的接收频率,应用关系模型实现客流数据的存储建模；为了减弱数据采集频率对实时客流查询效率的影响,建立多时间粒度的客流视图,可提高实时客流查询的计算效率.
The ALMA Real Time Control System
Kern, Jeffrey S.; Juerges, Thomas A.; Marson, Ralph G.
2009-01-01
The Atacama Large Millimeter Array (ALMA) is a revolutionary millimeter and submillimeter array being developed on the Atacama plateau of northern Chile. An international partnership lead by NRAO, ESO, and NAOJ this powerful and flexible telescope will provide unprecedented observations of this relatively unexplored frequency range. The control subsystem for the Atacama Large Millimeter Array must coordinate the monitor and control of at least sixty six antennas (in four different styles), two correlators, and all of the ancillary equipment (samplers, local oscillators, front ends, etc.). This equipment will be spread over tens of kilometers and operated remotely. Operation of the array requires a robust, scalable, and maintainable real time control system. The real time control system is responsible for monitoring and control of any devices where there are fixed deadlines. Examples in the ALMA context are antenna pointing and fringe tracking. Traditionally the real time portion of a large software system is an intricate and error prone portion of the software. As a result the real time portion is very expensive in terms of effort expended both during construction and during maintenance phases of a project. The ALMA real time control system uses a Linux based real time operating system to interact with the hardware and the CORBA based ALMA Common Software to communicate in the distributed computing environment. Mixing the requirements of real time computing and the non-deterministic CORBA middleware has produced an interesting design. We discuss the architecture, design, and implementation of the ALMA real time control system. Highlight some lessons learned along the way, and justify our assertion that this should be the last large scale real time control system in radio astronomy.
Achieving real-time performance in FIESTA
Wilkinson, William; Happell, Nadine; Miksell, Steve; Quillin, Robert; Carlisle, Candace
1988-01-01
The Fault Isolation Expert System for TDRSS Applications (FIESTA) is targeted for operation in a real-time online environment. Initial stages of the prototype development concentrated on acquisition and representation of the knowledge necessary to isolate faults in the TDRSS Network. Recent efforts focused on achieving real-time performance including: a discussion of the meaning of FIESTA real-time requirements, determination of performance levels (benchmarking) and techniques for optimization. Optimization techniques presented include redesign of critical relations, filtering of redundant data and optimization of patterns used in rules. Results are summarized.
Real-time medical applications and telecommunications.
Stravs, M
1999-01-01
Telecommunications play an important role in telemedicine. Many forms of telecommunication services based on different telecommunication technologies are developed for various needs. The paper deals with complex real-time applications which demand high telecommunication requirements. At the beginning, medical applications are categorised and real-time applications qualified as multimedia applications. Requirements for multimedia elements are listed separately. Later on, short introduction of related telecommunication protocols is given. Real-time medical applications can show their ability in case of guaranteed quality of services delivered by telecommunication network as it is explained in the end.