Science.gov

Sample records for real-time closed-loop processing

  1. Real-Time Process Monitoring by P-Polarized Reflectance Spectroscopy and Closed-Loop Control of Vapor Phase Epitaxy

    DTIC Science & Technology

    2000-01-01

    thickness and compositional graded multi-heterostructure GaxIn1-xP epilayers and validated by ex-situ post-growth analysis. This results in superior ...the SIMS profile analysis and the results clearly demonstrate superior tracking ability under closed-loop control, particularly in maintaining a...currently serves on the Editorial Boards of Quarterly of Applied Mathematics; International J. Mathematical and Computer Modeling; Matematica Aplicada

  2. Closed-loop real-time infrared scene generator

    NASA Astrophysics Data System (ADS)

    Crow, Dennis R.; Coker, Charles F.; Garbo, Dennis L.; Olson, Eric M.

    1998-07-01

    A computer program has been developed to provide closed-loop infrared imagery of composite targets and backgrounds in real- time. This program operates on parametric databases generated off-line by computationally intensive first principle physics codes such as the Composite Hardbody and Missile Plume (CHAMP) program, Synthetic Scene Generation Model (SSGM), and Multi- Spectral Modeling and Analysis (MSMA/Irma program. The parametric databases allow dynamic variations in flight and engagement scenarios to be modeled as closed-loop guidance and control algorithms modify the operational dynamics. The program is tightly coupled with the parametric databases to produce infrared radiation results in real-time and OpenGL graphic libraries to interface with high performance graphic hardware. The program is being sponsored for development by the Kinetic Kill Vehicle Hardware-in-the-Loop Simulator facility of the Air Force Research Laboratory Munitions Directorate located at Eglin AFB, Florida.

  3. Real-Time Closed Loop Modulated Turbine Cooling

    NASA Technical Reports Server (NTRS)

    Shyam, Vikram; Culley, Dennis E.; Eldridge, Jeffrey; Jones, Scott; Woike, Mark; Cuy, Michael

    2014-01-01

    It has been noted by industry that in addition to dramatic variations of temperature over a given blade surface, blade-to-blade variations also exist despite identical design. These variations result from manufacturing variations, uneven wear and deposition over the life of the part as well as limitations in the uniformity of coolant distribution in the baseline cooling design. It is proposed to combine recent advances in optical sensing, actuation, and film cooling concepts to develop a workable active, closed-loop modulated turbine cooling system to improve by 10 to 20 the turbine thermal state over the flight mission, to improve engine life and to dramatically reduce turbine cooling air usage and aircraft fuel burn. A reduction in oxides of nitrogen (NOx) can also be achieved by using the excess coolant to improve mixing in the combustor especially for rotorcraft engines. Recent patents filed by industry and universities relate to modulating endwall cooling using valves. These schemes are complex, add weight and are limited to the endwalls. The novelty of the proposed approach is twofold 1) Fluidic diverters that have no moving parts are used to modulate cooling and can operate under a wide range of conditions and environments. 2) Real-time optical sensing to map the thermal state of the turbine has never been attempted in realistic engine conditions.

  4. Hard real-time closed-loop electrophysiology with the Real-Time eXperiment Interface (RTXI)

    PubMed Central

    George, Ansel; Dorval, Alan D.; Christini, David J.

    2017-01-01

    The ability to experimentally perturb biological systems has traditionally been limited to static pre-programmed or operator-controlled protocols. In contrast, real-time control allows dynamic probing of biological systems with perturbations that are computed on-the-fly during experimentation. Real-time control applications for biological research are available; however, these systems are costly and often restrict the flexibility and customization of experimental protocols. The Real-Time eXperiment Interface (RTXI) is an open source software platform for achieving hard real-time data acquisition and closed-loop control in biological experiments while retaining the flexibility needed for experimental settings. RTXI has enabled users to implement complex custom closed-loop protocols in single cell, cell network, animal, and human electrophysiology studies. RTXI is also used as a free and open source, customizable electrophysiology platform in open-loop studies requiring online data acquisition, processing, and visualization. RTXI is easy to install, can be used with an extensive range of external experimentation and data acquisition hardware, and includes standard modules for implementing common electrophysiology protocols. PMID:28557998

  5. A Low-Cost Multielectrode System for Data Acquisition Enabling Real-Time Closed-Loop Processing with Rapid Recovery from Stimulation Artifacts

    PubMed Central

    Rolston, John D.; Gross, Robert E.; Potter, Steve M.

    2009-01-01

    Commercially available data acquisition systems for multielectrode recording from freely moving animals are expensive, often rely on proprietary software, and do not provide detailed, modifiable circuit schematics. When used in conjunction with electrical stimulation, they are prone to prolonged, saturating stimulation artifacts that prevent the recording of short-latency evoked responses. Yet electrical stimulation is integral to many experimental designs, and critical for emerging brain-computer interfacing and neuroprosthetic applications. To address these issues, we developed an easy-to-use, modifiable, and inexpensive system for multielectrode neural recording and stimulation. Setup costs are less than US$10,000 for 64 channels, an order of magnitude lower than comparable commercial systems. Unlike commercial equipment, the system recovers rapidly from stimulation and allows short-latency action potentials (<1 ms post-stimulus) to be detected, facilitating closed-loop applications and exposing neural activity that would otherwise remain hidden. To illustrate this capability, evoked activity from microstimulation of the rodent hippocampus is presented. System noise levels are similar to existing platforms, and extracellular action potentials and local field potentials can be recorded simultaneously. The system is modular, in banks of 16 channels, and flexible in usage: while primarily designed for in vivo use, it can be combined with commercial preamplifiers to record from in vitro multielectrode arrays. The system's open-source control software, NeuroRighter, is implemented in C#, with an easy-to-use graphical interface. As C# functions in a managed code environment, which may impact performance, analysis was conducted to ensure comparable speed to C++ for this application. Hardware schematics, layout files, and software are freely available. Since maintaining wired headstage connections with freely moving animals is difficult, we describe a new method of

  6. A low-cost multielectrode system for data acquisition enabling real-time closed-loop processing with rapid recovery from stimulation artifacts.

    PubMed

    Rolston, John D; Gross, Robert E; Potter, Steve M

    2009-01-01

    Commercially available data acquisition systems for multielectrode recording from freely moving animals are expensive, often rely on proprietary software, and do not provide detailed, modifiable circuit schematics. When used in conjunction with electrical stimulation, they are prone to prolonged, saturating stimulation artifacts that prevent the recording of short-latency evoked responses. Yet electrical stimulation is integral to many experimental designs, and critical for emerging brain-computer interfacing and neuroprosthetic applications. To address these issues, we developed an easy-to-use, modifiable, and inexpensive system for multielectrode neural recording and stimulation. Setup costs are less than US$10,000 for 64 channels, an order of magnitude lower than comparable commercial systems. Unlike commercial equipment, the system recovers rapidly from stimulation and allows short-latency action potentials (<1 ms post-stimulus) to be detected, facilitating closed-loop applications and exposing neural activity that would otherwise remain hidden. To illustrate this capability, evoked activity from microstimulation of the rodent hippocampus is presented. System noise levels are similar to existing platforms, and extracellular action potentials and local field potentials can be recorded simultaneously. The system is modular, in banks of 16 channels, and flexible in usage: while primarily designed for in vivo use, it can be combined with commercial preamplifiers to record from in vitro multielectrode arrays. The system's open-source control software, NeuroRighter, is implemented in C#, with an easy-to-use graphical interface. As C# functions in a managed code environment, which may impact performance, analysis was conducted to ensure comparable speed to C++ for this application. Hardware schematics, layout files, and software are freely available. Since maintaining wired headstage connections with freely moving animals is difficult, we describe a new method of

  7. A closed-loop brain computer interface for real-time seizure detection and control.

    PubMed

    Liang, Sheng-Fu; Shaw, Fu-Zen; Young, Chung-Ping; Chang, Da-Wei; Liao, Yi-Cheng

    2010-01-01

    The worldwide prevalence of epilepsy is approximately 1%, and 25% of epilepsy patients cannot be treated sufficiently by available therapies. Brain stimulation with closed-loop seizure control has recently been proposed as an innovative and effective alternative. In this paper, a portable closed-loop brain computer interface for seizure control was developed and shown with several aspects of advantages, including high seizure detection rate (92-99% during wake-sleep states), low false detection rate (1.2-2.5%), and small size. The seizure detection and electrical stimulation latency was not greater than 0.6 s after seizure onset. A wireless communication feature also provided flexibility for subjects freeing from the hassle of wires. Experimental data from freely moving rats supported the functional possibility of a real-time closed-loop seizure controller.

  8. Closed-loop optical stimulation and recording system with GPU-based real-time spike sorting

    NASA Astrophysics Data System (ADS)

    Wang, Ling; Nguyen, Thoa; Cabral, Henrique; Gysbrechts, Barbara; Battaglia, Francesco; Bartic, Carmen

    2014-05-01

    Closed-loop brain computer interfaces are rapidly progressing due to their applications in fundamental neuroscience and prosthetics. For optogenetic experiments, the integration of optical stimulation and electrophysiological recordings is emerging as an imperative engineering research topic. Optical stimulation does not only bring the advantage of cell-type selectivity, but also provides an alternative solution to the electrical stimulation-induced artifacts, a challenge in closedloop architectures. A closed-loop system must identify the neuronal signals in real-time such that a strategy is selected immediately (within a few milliseconds) for delivering stimulation patterns. Real-time spike sorting poses important challenges especially when a large number of recording channels are involved. Here we present a prototype allowing simultaneous optical stimulation and electro-physiological recordings in a closed-loop manner. The prototype was implemented with online spike detection and classification capabilities for selective cell stimulation. Real-time spike sorting was achieved by computations with a high speed, low cost graphic processing unit (GPU). We have successfully demonstrated the closed-loop operation, i.e. optical stimulation in vivo based on spike detection from 8 tetrodes (32 channels). The performance of GPU computation in spike sorting for different channel numbers and signal lengths was also investigated.

  9. A real-time pressure estimation algorithm for closed-loop combustion control

    NASA Astrophysics Data System (ADS)

    Al-Durra, Ahmed; Canova, Marcello; Yurkovich, Stephen

    2013-07-01

    The cylinder pressure is arguably the most important variable characterizing the combustion process in internal combustion engines. In light of the recent advances in combustion technologies and in engine control, the use of cylinder pressure is now frequently considered as a feedback signal for closed-loop combustion control algorithms. In order to generate an accurate pressure trace for real-time combustion control and diagnostics, the output of the in-cylinder pressure transducer must be conditioned with signal processing methods to mitigate the well-known issues of offset and noise. While several techniques have been proposed for processing the cylinder pressure signal with limited computational burden, most of the available methods still require one to apply low-pass filters or moving average windows in order to mitigate the noise. This ultimately limits the opportunity of exploiting the in-cylinder pressure feedback for a cycle-by-cycle control of the combustion process. To this extent, this paper presents an estimation algorithm that extracts the pressure signal from the in-cylinder sensor in real-time, allowing for estimating the 50% burn rate location and IMEP on a cycle-by-cycle basis. The proposed approach relies on a model-based estimation algorithm whose starting point is a crank-angle based engine combustion model that predicts the in-cylinder pressure from the definition of a burn rate function. Linear parameter varying (LPV) techniques are then used to expand the region of estimation to cover the engine operating map, as well as allowing for real-time cylinder estimation during transients. The estimator is tested on the experimental data collected on an engine dynamometer as well as on a high-fidelity engine simulator. The results obtained show the effectiveness of the estimator in reconstructing the cylinder pressure on a crank-angle basis and in rejecting measurement noise and modeling errors, with considerably low computation effort.

  10. Real-time closed-loop control for micro mirrors with quasistatic comb drives

    NASA Astrophysics Data System (ADS)

    Schroedter, Richard; Sandner, Thilo; Janschek, Klaus; Roth, Matthias; Hruschka, Clemens

    2016-03-01

    This paper presents the application of a real-time closed-loop control for the quasistatic axis of electrostatic micro scanning mirrors. In comparison to resonantly driven mirrors, the quasistatic comb drive allows arbitrary motion profiles with frequencies up to its eigenfrequency. A current mirror setup at Fraunhofer IPMS is manufactured with a staggered vertical comb (SVC) drive and equipped with an integrated piezo-resistive deflection sensor, which can potentially be used as position feedback sensor. The control design is accomplished based on a nonlinear mechatronic system model and the preliminary parameter characterization. In previous papers [1, 2] we have shown that jerk-limited trajectories, calculated offline, provide a suitable method for parametric trajectory design, taking into account physical limitations given by the electrostatic comb and thus decreasing the dynamic requirements. The open-loop control shows in general unfavorable residual eigenfrequency oscillations leading to considerable tracking errors for desired triangle trajectories [3]. With real-time closed-loop control, implemented on a dSPACE system using an optical feedback, we can significantly reduce these errors and stabilize the mirror motion against external disturbances. In this paper we compare linear and different nonlinear closed-loop control strategies as well as two observer variants for state estimation. Finally, we evaluate the simulation and experimental results in terms of steady state accuracy and the concept feasibility for a low-cost realization.

  11. Real-time, closed-loop dual-wavelength optical polarimetry for glucose monitoring

    NASA Astrophysics Data System (ADS)

    Malik, Bilal H.; Coté, Gerard L.

    2010-01-01

    The development of a real-time, dual-wavelength optical polarimetric system to ultimately probe the aqueous humor glucose concentrations as a means of noninvasive diabetic glucose monitoring is the long-term goal of this research. The key impact of the work is the development of an approach for the reduction of the time-variant corneal birefringence due to motion artifact, which is still a limiting factor preventing the realization of such a device. Our dual-wavelength approach utilizes real-time, closed-loop feedback that employs a classical three-term feedback controller and efficiently reduces the effect of motion artifact that appears as a common noise source for both wavelengths. In vitro results are shown for the open-loop system, and although the dual-wavelength system helps to reduce the noise, it is shown that closed-loop control is necessary to bring the noise down to a sufficient level for physiological monitoring. Specifically, in vitro measurement results with the closed-loop dual-wavelength approach demonstrate a sensitivity of 12.8 mg/dl across the physiologic glucose range in the presence of time-variant test cell birefringence. Overall, it is shown that this polarimetric system has the potential to be used as a noninvasive measure of glucose for diabetes.

  12. Real-time, closed-loop dual-wavelength optical polarimetry for glucose monitoring

    PubMed Central

    Malik, Bilal H.; Coté, Gerard L.

    2010-01-01

    The development of a real-time, dual-wavelength optical polarimetric system to ultimately probe the aqueous humor glucose concentrations as a means of noninvasive diabetic glucose monitoring is the long-term goal of this research. The key impact of the work is the development of an approach for the reduction of the time-variant corneal birefringence due to motion artifact, which is still a limiting factor preventing the realization of such a device. Our dual-wavelength approach utilizes real-time, closed-loop feedback that employs a classical three-term feedback controller and efficiently reduces the effect of motion artifact that appears as a common noise source for both wavelengths. In vitro results are shown for the open-loop system, and although the dual-wavelength system helps to reduce the noise, it is shown that closed-loop control is necessary to bring the noise down to a sufficient level for physiological monitoring. Specifically, in vitro measurement results with the closed-loop dual-wavelength approach demonstrate a sensitivity of 12.8 mg∕dl across the physiologic glucose range in the presence of time-variant test cell birefringence. Overall, it is shown that this polarimetric system has the potential to be used as a noninvasive measure of glucose for diabetes. PMID:20210476

  13. Real-time Electrophysiology: Using Closed-loop Protocols to Probe Neuronal Dynamics and Beyond.

    PubMed

    Linaro, Daniele; Couto, João; Giugliano, Michele

    2015-06-24

    Experimental neuroscience is witnessing an increased interest in the development and application of novel and often complex, closed-loop protocols, where the stimulus applied depends in real-time on the response of the system. Recent applications range from the implementation of virtual reality systems for studying motor responses both in mice and in zebrafish, to control of seizures following cortical stroke using optogenetics. A key advantage of closed-loop techniques resides in the capability of probing higher dimensional properties that are not directly accessible or that depend on multiple variables, such as neuronal excitability and reliability, while at the same time maximizing the experimental throughput. In this contribution and in the context of cellular electrophysiology, we describe how to apply a variety of closed-loop protocols to the study of the response properties of pyramidal cortical neurons, recorded intracellularly with the patch clamp technique in acute brain slices from the somatosensory cortex of juvenile rats. As no commercially available or open source software provides all the features required for efficiently performing the experiments described here, a new software toolbox called LCG was developed, whose modular structure maximizes reuse of computer code and facilitates the implementation of novel experimental paradigms. Stimulation waveforms are specified using a compact meta-description and full experimental protocols are described in text-based configuration files. Additionally, LCG has a command-line interface that is suited for repetition of trials and automation of experimental protocols.

  14. A reconfigurable visual-programming library for real-time closed-loop cellular electrophysiology.

    PubMed

    Biró, István; Giugliano, Michele

    2015-01-01

    Most of the software platforms for cellular electrophysiology are limited in terms of flexibility, hardware support, ease of use, or re-configuration and adaptation for non-expert users. Moreover, advanced experimental protocols requiring real-time closed-loop operation to investigate excitability, plasticity, dynamics, are largely inaccessible to users without moderate to substantial computer proficiency. Here we present an approach based on MATLAB/Simulink, exploiting the benefits of LEGO-like visual programming and configuration, combined to a small, but easily extendible library of functional software components. We provide and validate several examples, implementing conventional and more sophisticated experimental protocols such as dynamic-clamp or the combined use of intracellular and extracellular methods, involving closed-loop real-time control. The functionality of each of these examples is demonstrated with relevant experiments. These can be used as a starting point to create and support a larger variety of electrophysiological tools and methods, hopefully extending the range of default techniques and protocols currently employed in experimental labs across the world.

  15. A reconfigurable visual-programming library for real-time closed-loop cellular electrophysiology

    PubMed Central

    Biró, István; Giugliano, Michele

    2015-01-01

    Most of the software platforms for cellular electrophysiology are limited in terms of flexibility, hardware support, ease of use, or re-configuration and adaptation for non-expert users. Moreover, advanced experimental protocols requiring real-time closed-loop operation to investigate excitability, plasticity, dynamics, are largely inaccessible to users without moderate to substantial computer proficiency. Here we present an approach based on MATLAB/Simulink, exploiting the benefits of LEGO-like visual programming and configuration, combined to a small, but easily extendible library of functional software components. We provide and validate several examples, implementing conventional and more sophisticated experimental protocols such as dynamic-clamp or the combined use of intracellular and extracellular methods, involving closed-loop real-time control. The functionality of each of these examples is demonstrated with relevant experiments. These can be used as a starting point to create and support a larger variety of electrophysiological tools and methods, hopefully extending the range of default techniques and protocols currently employed in experimental labs across the world. PMID:26157385

  16. Closed-loop training of attention with real-time brain imaging.

    PubMed

    deBettencourt, Megan T; Cohen, Jonathan D; Lee, Ray F; Norman, Kenneth A; Turk-Browne, Nicholas B

    2015-03-01

    Lapses of attention can have negative consequences, including accidents and lost productivity. Here we used closed-loop neurofeedback to improve sustained attention abilities and reduce the frequency of lapses. During a sustained attention task, the focus of attention was monitored in real time with multivariate pattern analysis of whole-brain neuroimaging data. When indicators of an attentional lapse were detected in the brain, we gave human participants feedback by making the task more difficult. Behavioral performance improved after one training session, relative to control participants who received feedback from other participants' brains. This improvement was largest when feedback carried information from a frontoparietal attention network. A neural consequence of training was that the basal ganglia and ventral temporal cortex came to represent attentional states more distinctively. These findings suggest that attentional failures do not reflect an upper limit on cognitive potential and that attention can be trained with appropriate feedback about neural signals.

  17. Real-Time Monitoring and Prediction of the Pilot Vehicle System (PVS) Closed-Loop Stability

    NASA Astrophysics Data System (ADS)

    Mandal, Tanmay Kumar

    Understanding human control behavior is an important step for improving the safety of future aircraft. Considerable resources are invested during the design phase of an aircraft to ensure that the aircraft has desirable handling qualities. However, human pilots exhibit a wide range of control behaviors that are a function of external stimulus, aircraft dynamics, and human psychological properties (such as workload, stress factor, confidence, and sense of urgency factor). This variability is difficult to address comprehensively during the design phase and may lead to undesirable pilot-aircraft interaction, such as pilot-induced oscillations (PIO). This creates the need to keep track of human pilot performance in real-time to monitor the pilot vehicle system (PVS) stability. This work focused on studying human pilot behavior for the longitudinal axis of a remotely controlled research aircraft and using human-in-the-loop (HuIL) simulations to obtain information about the human controlled system (HCS) stability. The work in this dissertation is divided into two main parts: PIO analysis and human control model parameters estimation. To replicate different flight conditions, this study included time delay and elevator rate limiting phenomena, typical of actuator dynamics during the experiments. To study human control behavior, this study employed the McRuer model for single-input single-output manual compensatory tasks. McRuer model is a lead-lag controller with time delay which has been shown to adequately model manual compensatory tasks. This dissertation presents a novel technique to estimate McRuer model parameters in real-time and associated validation using HuIL simulations to correctly predict HCS stability. The McRuer model parameters were estimated in real-time using a Kalman filter approach. The estimated parameters were then used to analyze the stability of the closed-loop HCS and verify them against the experimental data. Therefore, the main contribution of

  18. Dynamic closed-loop test for real-time drift angle adjustment of space camera on the Earth

    NASA Astrophysics Data System (ADS)

    Hu, Jun; Cao, Xiaotao; Wang, Dong; Wu, Weiping; Xu, Shuyan

    2010-10-01

    In order to eliminate the influence of aircraft attitude angle to the image quality of space camera, and assure that the drift angle of space camera could be accurately adjusted at the orbit, a novel closed-loop test method is provided for real-time drift angle adjustment of space camera on the Earth. A long focal length dynamic aim generator is applied to simulate the image motion and the variety drift angle, and to detect the precision of the image motion compensation machinery and the capability of the drift angle control system. The computer system is used to control the dynamic aim generator, accomplish the data processing, transmit and receive the data information. The seamless connection and the data transmission between the aim generator and the aircraft simulation devices are constituted. The command, parameter and drift angle data transmitted by the simulation devices are received by the space camera at the real time, then the photos are taken and the draft angle is adjusted simultaneously. It is shown that the drift angle can be accurately tracked by the space camera at the real time, and the detective method satisfies the test requirement.

  19. A real-time and closed-loop control algorithm for cascaded multilevel inverter based on artificial neural network.

    PubMed

    Wang, Libing; Mao, Chengxiong; Wang, Dan; Lu, Jiming; Zhang, Junfeng; Chen, Xun

    2014-01-01

    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.

  20. A Real-Time and Closed-Loop Control Algorithm for Cascaded Multilevel Inverter Based on Artificial Neural Network

    PubMed Central

    Wang, Libing; Mao, Chengxiong; Wang, Dan; Lu, Jiming; Zhang, Junfeng; Chen, Xun

    2014-01-01

    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. PMID:24772025

  1. Closed-loop glucose control in critically ill patients using continuous glucose monitoring system (CGMS) in real time.

    PubMed

    Chee, Frederick; Fernando, Tyrone; van Heerden, P Vernon

    2003-03-01

    A study was conducted to determine if continuous subcutaneous glucose monitoring (from MiniMed CGMS) could be used in real-time to control blood sugar level (BSL) in patients with critical illness. A closed-loop control system was constructed to use CGMS in a real-time manner, coupled with a proportional integral (PI) control algorithm based on a sliding scale approach, for automatic intravenous infusion of insulin to patients. A total of five subjects with high BSL (> 10 mmol/L) participated in formal studies of the closed-loop control system. Subjects were recruited from critically ill patients in the intensive care unit (ICU) after informed consent was obtained. Error grid analysis showed that 64.6% of the BSL readings as determined in real time using CGMS sensor, when compared to conventional BSL measurements on blood drawn from an arterial line, was clinically accurate (i.e., < 20% deviation from glucometer value). In the five patients who underwent closed-loop control, the controller managed to control only one patient's glycaemia without any manual intervention. Manual intervention was required due to the real-time sensor reading deviating more than 20% from the glucometer value, and also as a safety mechanism. Test on equality of mean and variance for BSL attained prior to, during, and post trial showed that the controller's performance was comparable to manual control. We conclude that the automatic sliding scale approach of closed-loop BSL control is feasible in patients in intensive care. More work is needed in the refinement of the algorithm and the improvement of real-time sensor accuracy.

  2. Real-time Closed-loop Control in a Rodent Model of Medically-induced Coma Using Burst Suppression

    PubMed Central

    Ching, ShiNung; Liberman, Max Y.; Chemali, Jessica J.; Westover, M. Brandon; Kenny, Jonathan; Solt, Ken; Purdon, Patrick L.; Brown, Emery N.

    2013-01-01

    Background A medically-induced coma is an anesthetic state of profound brain inactivation created to treat status epilepticus and to provide cerebral protection following traumatic brain injuries. We hypothesized that a closed-loop anesthetic delivery system could automatically and precisely control the electroencephalogram state of burst suppression and efficiently maintain a medically-induced coma. Methods In six rats, we implemented a closed-loop anesthetic delivery system for propofol consisting of: a computer-controlled pump infusion, a two-compartment pharmacokinetics model defining propofol’s electroencephalogram effects, the burst suppression probability algorithm to compute in real time from the electroencephalogram the brain’s burst suppression state, an on-line parameter estimation procedure and a proportional-integral controller. In the control experiment each rat was randomly assigned to one of the six burst suppression probability target trajectories constructed by permuting the burst suppression probability levels of 0.4, 0.65 and 0.9 with linear transitions between levels. Results In each animal the controller maintained approximately 60 min of tight, real-time control of burst suppression by tracking each burst suppression probability target level for 15 min and two between-level transitions for 5 to 10 min. The posterior probability that the closed-loop anesthetic delivery system was reliable across all levels was 0.94 [95% confidence interval; (0.77 to 1.00) n = 18] and that the system was accurate was 1.00 [95% confidence interval; (0.84 to 1.00) n = 18]. Conclusion Our findings establish the feasibility of using a closed-loop anesthetic delivery systems to achieve in real-time reliable and accurate control of burst suppression in rodents and suggest a paradigm to precisely control medically-induced coma in patients. PMID:23770601

  3. Real-time closed-loop control in a rodent model of medically induced coma using burst suppression.

    PubMed

    Ching, ShiNung; Liberman, Max Y; Chemali, Jessica J; Westover, M Brandon; Kenny, Jonathan D; Solt, Ken; Purdon, Patrick L; Brown, Emery N

    2013-10-01

    A medically induced coma is an anesthetic state of profound brain inactivation created to treat status epilepticus and to provide cerebral protection after traumatic brain injuries. The authors hypothesized that a closed-loop anesthetic delivery system could automatically and precisely control the electroencephalogram state of burst suppression and efficiently maintain a medically induced coma. In six rats, the authors implemented a closed-loop anesthetic delivery system for propofol consisting of: a computer-controlled pump infusion, a two-compartment pharmacokinetics model defining propofol's electroencephalogram effects, the burst-suppression probability algorithm to compute in real time from the electroencephalogram the brain's burst-suppression state, an online parameter-estimation procedure and a proportional-integral controller. In the control experiment each rat was randomly assigned to one of the six burst-suppression probability target trajectories constructed by permuting the burst-suppression probability levels of 0.4, 0.65, and 0.9 with linear transitions between levels. In each animal the controller maintained approximately 60 min of tight, real-time control of burst suppression by tracking each burst-suppression probability target level for 15 min and two between-level transitions for 5-10 min. The posterior probability that the closed-loop anesthetic delivery system was reliable across all levels was 0.94 (95% CI, 0.77-1.00; n = 18) and that the system was accurate across all levels was 1.00 (95% CI, 0.84-1.00; n = 18). The findings of this study establish the feasibility of using a closed-loop anesthetic delivery systems to achieve in real time reliable and accurate control of burst suppression in rodents and suggest a paradigm to precisely control medically induced coma in patients.

  4. Using GPU convolutions to correct optical distortion in closed-loop real-time missile simulations

    NASA Astrophysics Data System (ADS)

    Fronckowiak, Thomas, Jr.

    2009-05-01

    U.S. Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) has long been a leader in in-band high fidelity scientific scene generation. Recent efforts to harness and exploit the parallel power of the Graphics Processor Unit (GPU), for both graphics and general purpose processing, have been paramount. The emergence of sophisticated image generation software packages, such as the Common Scene Generator (CSG) and the Joint Signature Image Generator (JSIG), have lead to a sharp increase in the performance of digital simulations and signal injection and projection systems in both tactical and strategic programs. One area of missile simulations that benefits from this technology is real-time modeling of optical effects, such as seeker dome distortion, glint, blurring effects, and correcting for facility misalignment and distortion. This paper discusses the on-going research of applying convolution filters to the GPU multi-pass rendering process to compensate for spatial distortion in the optical projection path for synthetic environments.

  5. Closed-loop 15N measurement of N2O and its isotopomers for real-time greenhouse gas tracing

    NASA Astrophysics Data System (ADS)

    Slaets, Johanna; Mayr, Leopold; Heiling, Maria; Zaman, Mohammad; Resch, Christian; Weltin, Georg; Gruber, Roman; Dercon, Gerd

    2016-04-01

    Quantifying sources of nitrous oxide is essential to improve understanding of the global N cycle and to develop climate-smart agriculture, as N2O has a global warming potential 300 times higher than CO2. The isotopic signature and the intramolecular distribution (site preference) of 15N are powerful tools to trace N2O, but the application of these methods is limited as conventional methods cannot provide continuous and in situ data. Here we present a method for closed-loop, real time monitoring of the N2O flux, the isotopic signature and the intramolecular distribution of 15N by using off-axis integrated cavity output spectroscopy (ICOS, Los Gatos Research). The developed method was applied to a fertilizer inhibitor experiment, in which N2O emissions were measured on undisturbed soil cores for three weeks. The treatments consisted of enriched urea-N (100 kg urea-N/ha), the same fertilizer combined with the nitrification inhibitor nitrapyrin (375 g/100 kg urea), and control cores. Monitoring the isotopic signature makes it possible to distinguish emissions from soil and fertilizer. Characterization of site preference could additionally provide a tool to identify different microbial processes leading to N2O emissions. Furthermore, the closed-loop approach enables direct measurement on site and does not require removal of CO2 and H2O. Results showed that 75% of total N2O emissions (total=11 346 μg N2O-N/m2) in the fertilized cores originated from fertilizer, while only 55% of total emissions (total=2 450 μg N2ON/m2) stemmed from fertilizer for the cores treated with nitrapyrin. In the controls, N2O derived from soil was only 40% of the size of the corresponding pool from the fertilized cores, pointing towards a priming effect on the microbial community from the fertilizer and demonstrating the bias that could be introduced by relying on non-treated cores to estimate soil emission rates, rather than using the isotopic signature. The site preference increased linearly

  6. Incorporating real time velocity map image reconstruction into closed-loop coherent control

    NASA Astrophysics Data System (ADS)

    Rallis, C. E.; Burwitz, T. G.; Andrews, P. R.; Zohrabi, M.; Averin, R.; De, S.; Bergues, B.; Jochim, Bethany; Voznyuk, A. V.; Gregerson, Neal; Gaire, B.; Znakovskaya, I.; McKenna, J.; Carnes, K. D.; Kling, M. F.; Ben-Itzhak, I.; Wells, E.

    2014-11-01

    We report techniques developed to utilize three-dimensional momentum information as feedback in adaptive femtosecond control of molecular dynamics. Velocity map imaging is used to obtain the three-dimensional momentum map of the dissociating ions following interaction with a shaped intense ultrafast laser pulse. In order to recover robust feedback information, however, the two-dimensional momentum projection from the detector must be inverted to reconstruct the full three-dimensional momentum of the photofragments. These methods are typically slow or require manual inputs and are therefore accomplished offline after the images have been obtained. Using an algorithm based upon an "onion-peeling" (also known as "back projection") method, we are able to invert 1040 × 1054 pixel images in under 1 s. This rapid inversion allows the full photofragment momentum to be used as feedback in a closed-loop adaptive control scheme, in which a genetic algorithm tailors an ultrafast laser pulse to optimize a specific outcome. Examples of three-dimensional velocity map image based control applied to strong-field dissociation of CO and O2 are presented.

  7. A closed-loop anesthetic delivery system for real-time control of burst suppression

    NASA Astrophysics Data System (ADS)

    Liberman, Max Y.; Ching, ShiNung; Chemali, Jessica; Brown, Emery N.

    2013-08-01

    Objective. There is growing interest in using closed-loop anesthetic delivery (CLAD) systems to automate control of brain states (sedation, unconsciousness and antinociception) in patients receiving anesthesia care. The accuracy and reliability of these systems can be improved by using as control signals electroencephalogram (EEG) markers for which the neurophysiological links to the anesthetic-induced brain states are well established. Burst suppression, in which bursts of electrical activity alternate with periods of quiescence or suppression, is a well-known, readily discernible EEG marker of profound brain inactivation and unconsciousness. This pattern is commonly maintained when anesthetics are administered to produce a medically-induced coma for cerebral protection in patients suffering from brain injuries or to arrest brain activity in patients having uncontrollable seizures. Although the coma may be required for several hours or days, drug infusion rates are managed inefficiently by manual adjustment. Our objective is to design a CLAD system for burst suppression control to automate management of medically-induced coma. Approach. We establish a CLAD system to control burst suppression consisting of: a two-dimensional linear system model relating the anesthetic brain level to the EEG dynamics; a new control signal, the burst suppression probability (BSP) defining the instantaneous probability of suppression; the BSP filter, a state-space algorithm to estimate the BSP from EEG recordings; a proportional-integral controller; and a system identification procedure to estimate the model and controller parameters. Main results. We demonstrate reliable performance of our system in simulation studies of burst suppression control using both propofol and etomidate in rodent experiments based on Vijn and Sneyd, and in human experiments based on the Schnider pharmacokinetic model for propofol. Using propofol, we further demonstrate that our control system reliably

  8. A Closed-Loop Anesthetic Delivery System for Real-Time Control of Burst Suppression

    PubMed Central

    Liberman, Max Y.; Ching, ShiNung; Chemali, Jessica; Brown, Emery N.

    2013-01-01

    Objective There is growing interest in using closed-loop anesthetic delivery (CLAD) systems to automate control of brain states (sedation, unconsciousness and antinociception) in patients receiving anesthesia care. The accuracy and reliability of these systems can be improved by using as control signals electroencephalogram (EEG) markers for which the neurophysiological links to the anesthetic-induced brain states are well established. Burst suppression, in which bursts of electrical activity alternate with periods of quiescence or suppression, is a well-known, readily discernible EEG marker of profound brain inactivation and unconsciousness. This pattern is commonly maintained when anesthetics are administered to produce a medically-induced coma for cerebral protection in patients suffering from brain injuries or to arrest brain activity in patients having uncontrollable seizures. Although the coma may be required for several hours or days, drug infusion rates are managed inefficiently by manual adjustment. Our objective is to design a CLAD system for burst suppression control to automate management of medically-induced coma. Approach We establish a CLAD system to control burst suppression consisting of: a two-dimensional linear system model relating the anesthetic brain level to the EEG dynamics; a new control signal, the burst suppression probability (BSP) defining the instantaneous probability of suppression; the BSP filter, a state-space algorithm to estimate the BSP from EEG recordings; a proportional-integral controller; and a system identification procedure to estimate the model and controller parameters. Main Results We demonstrate reliable performance of our system in simulation studies of burst suppression control using both propofol and etomidate in rodent experiments based on Vijn and Sneyd, and in human experiments based on the Schnider pharmacokinetic model for propofol. Using propofol, we further demonstrate that our control system reliably tracks

  9. The Stomatogastric Nervous System as a Model for Studying Sensorimotor Interactions in Real-Time Closed-Loop Conditions

    PubMed Central

    Daur, Nelly; Diehl, Florian; Mader, Wolfgang; Stein, Wolfgang

    2012-01-01

    The perception of proprioceptive signals that report the internal state of the body is one of the essential tasks of the nervous system and helps to continuously adapt body movements to changing circumstances. Despite the impact of proprioceptive feedback on motor activity it has rarely been studied in conditions in which motor output and sensory activity interact as they do in behaving animals, i.e., in closed-loop conditions. The interaction of motor and sensory activities, however, can create emergent properties that may govern the functional characteristics of the system. We here demonstrate a method to use a well-characterized model system for central pattern generation, the stomatogastric nervous system, for studying these properties in vitro. We created a real-time computer model of a single-cell muscle tendon organ in the gastric mill of the crab foregut that uses intracellular current injections to control the activity of the biological proprioceptor. The resulting motor output of a gastric mill motor neuron is then recorded intracellularly and fed into a simple muscle model consisting of a series of low-pass filters. The muscle output is used to activate a one-dimensional Hodgkin–Huxley type model of the muscle tendon organ in real-time, allowing closed-loop conditions. Model properties were either hand tuned to achieve the best match with data from semi-intact muscle preparations, or an exhaustive search was performed to determine the best set of parameters. We report the real-time capabilities of our models, its performance and its interaction with the biological motor system. PMID:22435059

  10. Closed-Loop Process Control for Electron Beam Freeform Fabrication and Deposition Processes

    NASA Technical Reports Server (NTRS)

    Taminger, Karen M. (Inventor); Hafley, Robert A. (Inventor); Martin, Richard E. (Inventor); Hofmeister, William H. (Inventor)

    2013-01-01

    A closed-loop control method for an electron beam freeform fabrication (EBF(sup 3)) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF(sup 3) process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF(sup 3) apparatus to control the EBF(sup 3) process in a closed-loop manner.

  11. Closed-loop real-time simulation model of hemodynamics and oxygen transport in the cardiovascular system

    PubMed Central

    2013-01-01

    Background Computer technology enables realistic simulation of cardiovascular physiology. The increasing number of clinical surgical and medical treatment options imposes a need for better understanding of patient-specific pathology and outcome prediction. Methods A distributed lumped parameter real-time closed-loop model with 26 vascular segments, cardiac modelling with time-varying elastance functions and gradually opening and closing valves, the pericardium, intrathoracic pressure, the atrial and ventricular septum, various pathological states and including oxygen transport has been developed. Results Model output is pressure, volume, flow and oxygen saturation from every cardiac and vascular compartment. The model produces relevant clinical output and validation of quantitative data in normal physiology and qualitative directions in simulation of pathological states show good agreement with published data. Conclusion The results show that it is possible to build a clinically relevant real-time computer simulation model of the normal adult cardiovascular system. It is suggested that understanding qualitative interaction between physiological parameters in health and disease may be improved by using the model, although further model development and validation is needed for quantitative patient-specific outcome prediction. PMID:23842033

  12. Closed-loop real-time simulation model of hemodynamics and oxygen transport in the cardiovascular system.

    PubMed

    Broomé, Michael; Maksuti, Elira; Bjällmark, Anna; Frenckner, Björn; Janerot-Sjöberg, Birgitta

    2013-07-10

    Computer technology enables realistic simulation of cardiovascular physiology. The increasing number of clinical surgical and medical treatment options imposes a need for better understanding of patient-specific pathology and outcome prediction. A distributed lumped parameter real-time closed-loop model with 26 vascular segments, cardiac modelling with time-varying elastance functions and gradually opening and closing valves, the pericardium, intrathoracic pressure, the atrial and ventricular septum, various pathological states and including oxygen transport has been developed. Model output is pressure, volume, flow and oxygen saturation from every cardiac and vascular compartment. The model produces relevant clinical output and validation of quantitative data in normal physiology and qualitative directions in simulation of pathological states show good agreement with published data. The results show that it is possible to build a clinically relevant real-time computer simulation model of the normal adult cardiovascular system. It is suggested that understanding qualitative interaction between physiological parameters in health and disease may be improved by using the model, although further model development and validation is needed for quantitative patient-specific outcome prediction.

  13. Real-time closed-loop simulation and upset evaluation of control systems in harsh electromagnetic environments

    NASA Technical Reports Server (NTRS)

    Belcastro, Celeste M.

    1989-01-01

    Digital control systems for applications such as aircraft avionics and multibody systems must maintain adequate control integrity in adverse as well as nominal operating conditions. For example, control systems for advanced aircraft, and especially those with relaxed static stability, will be critical to flight and will, therefore, have very high reliability specifications which must be met regardless of operating conditions. In addition, multibody systems such as robotic manipulators performing critical functions must have control systems capable of robust performance in any operating environment in order to complete the assigned task reliably. Severe operating conditions for electronic control systems can result from electromagnetic disturbances caused by lightning, high energy radio frequency (HERF) transmitters, and nuclear electromagnetic pulses (NEMP). For this reason, techniques must be developed to evaluate the integrity of the control system in adverse operating environments. The most difficult and illusive perturbations to computer-based control systems that can be caused by an electromagnetic environment (EME) are functional error modes that involve no component damage. These error modes are collectively known as upset, can occur simultaneously in all of the channels of a redundant control system, and are software dependent. Upset studies performed to date have not addressed the assessment of fault tolerant systems and do not involve the evaluation of a control system operating in a closed-loop with the plant. A methodology for performing a real-time simulation of the closed-loop dynamics of a fault tolerant control system with a simulated plant operating in an electromagnetically harsh environment is presented. In particular, considerations for performing upset tests on the controller are discussed. Some of these considerations are the generation and coupling of analog signals representative of electromagnetic disturbances to a control system under test

  14. Perception as a closed-loop convergence process

    PubMed Central

    Ahissar, Ehud; Assa, Eldad

    2016-01-01

    Perception of external objects involves sensory acquisition via the relevant sensory organs. A widely-accepted assumption is that the sensory organ is the first station in a serial chain of processing circuits leading to an internal circuit in which a percept emerges. This open-loop scheme, in which the interaction between the sensory organ and the environment is not affected by its concurrent downstream neuronal processing, is strongly challenged by behavioral and anatomical data. We present here a hypothesis in which the perception of external objects is a closed-loop dynamical process encompassing loops that integrate the organism and its environment and converging towards organism-environment steady-states. We discuss the consistency of closed-loop perception (CLP) with empirical data and show that it can be synthesized in a robotic setup. Testable predictions are proposed for empirical distinction between open and closed loop schemes of perception. DOI: http://dx.doi.org/10.7554/eLife.12830.001 PMID:27159238

  15. The Automatic Neuroscientist: A framework for optimizing experimental design with closed-loop real-time fMRI

    PubMed Central

    Lorenz, Romy; Monti, Ricardo Pio; Violante, Inês R.; Anagnostopoulos, Christoforos; Faisal, Aldo A.; Montana, Giovanni; Leech, Robert

    2016-01-01

    Functional neuroimaging typically explores how a particular task activates a set of brain regions. Importantly though, the same neural system can be activated by inherently different tasks. To date, there is no approach available that systematically explores whether and how distinct tasks probe the same neural system. Here, we propose and validate an alternative framework, the Automatic Neuroscientist, which turns the standard fMRI approach on its head. We use real-time fMRI in combination with modern machine-learning techniques to automatically design the optimal experiment to evoke a desired target brain state. In this work, we present two proof-of-principle studies involving perceptual stimuli. In both studies optimization algorithms of varying complexity were employed; the first involved a stochastic approximation method while the second incorporated a more sophisticated Bayesian optimization technique. In the first study, we achieved convergence for the hypothesized optimum in 11 out of 14 runs in less than 10 min. Results of the second study showed how our closed-loop framework accurately and with high efficiency estimated the underlying relationship between stimuli and neural responses for each subject in one to two runs: with each run lasting 6.3 min. Moreover, we demonstrate that using only the first run produced a reliable solution at a group-level. Supporting simulation analyses provided evidence on the robustness of the Bayesian optimization approach for scenarios with low contrast-to-noise ratio. This framework is generalizable to numerous applications, ranging from optimizing stimuli in neuroimaging pilot studies to tailoring clinical rehabilitation therapy to patients and can be used with multiple imaging modalities in humans and animals. PMID:26804778

  16. Closed Loop Control of Penetration Depth during CO2 Laser Lap Welding Processes

    PubMed Central

    Sibillano, Teresa; Rizzi, Domenico; Mezzapesa, Francesco P.; Lugarà, Pietro Mario; Konuk, Ali Riza; Aarts, Ronald; Veld, Bert Huis in 't; Ancona, Antonio

    2012-01-01

    In this paper we describe a novel spectroscopic closed loop control system capable of stabilizing the penetration depth during laser welding processes by controlling the laser power. Our novel approach is to analyze the optical emission from the laser generated plasma plume above the keyhole, to calculate its electron temperature as a process-monitoring signal. Laser power has been controlled by using a quantitative relationship between the penetration depth and the plasma electron temperature. The sensor is able to correlate in real time the difference between the measured electron temperature and its reference value for the requested penetration depth. Accordingly the closed loop system adjusts the power, thus maintaining the penetration depth. PMID:23112646

  17. A closed-loop air revitalization process technology demonstrator

    NASA Astrophysics Data System (ADS)

    Mulloth, Lila; Perry, Jay; Luna, Bernadette; Kliss, Mark

    Demonstrating a sustainable, reliable life support system process design that possesses the capability to close the oxygen cycle to the greatest extent possible is required for extensive surface exploration of the Moon and Mars by humans. A conceptual closed-loop air revitalization system process technology demonstrator that combines the CO2 removal, recovery, and reduction and oxygen generation operations in a single compact envelope is described. NASA has developed, and in some cases flown, process technologies for capturing metabolic CO2 from air, reducing CO2 to H2O and CH4, electrolyzing H2O to O2, and electrolyzing CO2 to O2 and CO among a number of candidates. Traditionally, these processes either operate in parallel with one another or have not taken full benefit of a unit operation-based design approach to take complete advantage of the synergy between individual technologies. The appropriate combination of process technologies must capitalize on the advantageous aspects of individual technologies while eliminating or transforming the features that limit their feasibility when considered alone. Such a process technology integration approach also provides advantages of optimized mass, power and volume characteristics for the hardware embodiment. The conceptual air revitalization system process design is an ideal technology demonstrator for the critically needed closed-loop life support capabilities for long duration human exploration of the lunar surface and extending crewed space exploration toward Mars. The conceptual process design incorporates low power CO2 removal, process gas drying, and advanced engineered adsorbents being developed by NASA and industry.

  18. Gait adaptation to visual kinematic perturbations using a real-time closed-loop brain-computer interface to a virtual reality avatar

    NASA Astrophysics Data System (ADS)

    Phat Luu, Trieu; He, Yongtian; Brown, Samuel; Nakagome, Sho; Contreras-Vidal, Jose L.

    2016-06-01

    Objective. The control of human bipedal locomotion is of great interest to the field of lower-body brain-computer interfaces (BCIs) for gait rehabilitation. While the feasibility of closed-loop BCI systems for the control of a lower body exoskeleton has been recently shown, multi-day closed-loop neural decoding of human gait in a BCI virtual reality (BCI-VR) environment has yet to be demonstrated. BCI-VR systems provide valuable alternatives for movement rehabilitation when wearable robots are not desirable due to medical conditions, cost, accessibility, usability, or patient preferences. Approach. In this study, we propose a real-time closed-loop BCI that decodes lower limb joint angles from scalp electroencephalography (EEG) during treadmill walking to control a walking avatar in a virtual environment. Fluctuations in the amplitude of slow cortical potentials of EEG in the delta band (0.1-3 Hz) were used for prediction; thus, the EEG features correspond to time-domain amplitude modulated potentials in the delta band. Virtual kinematic perturbations resulting in asymmetric walking gait patterns of the avatar were also introduced to investigate gait adaptation using the closed-loop BCI-VR system over a period of eight days. Main results. Our results demonstrate the feasibility of using a closed-loop BCI to learn to control a walking avatar under normal and altered visuomotor perturbations, which involved cortical adaptations. The average decoding accuracies (Pearson’s r values) in real-time BCI across all subjects increased from (Hip: 0.18 ± 0.31 Knee: 0.23 ± 0.33 Ankle: 0.14 ± 0.22) on Day 1 to (Hip: 0.40 ± 0.24 Knee: 0.55 ± 0.20 Ankle: 0.29 ± 0.22) on Day 8. Significance. These findings have implications for the development of a real-time closed-loop EEG-based BCI-VR system for gait rehabilitation after stroke and for understanding cortical plasticity induced by a closed-loop BCI-VR system.

  19. Application of a ground based minicomputer system for real time, closed loop control of remotely piloted aircraft models used in stall/spin research

    NASA Technical Reports Server (NTRS)

    Montoya, R. J.; Jai, A. R.

    1979-01-01

    The paper describes a minicomputer-based, real-time closed loop remote control system at NASA Langley outdoor facility which is used to determine the stall/departure/spin characteristics of high-performance aircraft. The experiments are conducted with 15% dynamically scaled, unpowered models that are dropped from 3000 m and ground controlled. The effects of time delays and sampling rates on the stability of the control system and the selection of digital algorithms to meet frequency response and real time constraints are examined. Also described is the implementation of the modular software for the flexible programming of multi-axis control laws.

  20. Designing optimized industrial process analysers for closed loop control

    PubMed Central

    Grevesmuehl, Bernard; Kradjel, Cynthia; Kellner, Hanno

    1991-01-01

    Manufacturers are now looking closely at ways of optimizing ‘quality’ and increasing process efficiency while reducing manufacturing costs. Near infra-red (NIR) technology is a popular solution to this challenge: it provides manufacturers with rapid and reliable in-process analysis and thousands of systems have already been installed in the food, chemical, pharmaceutical and agricultural markets. For over 10 years, NIR has been successfully applied to at-line process analysis. Rugged and easy-to-operate filter analysers are traditionally located in the control room–process operators can then ‘grab samples’ and obtain results in less than a minute. There are many practical advantages to using at-line filter systems. Products from many lines can be run on one system, and, since there is no direct process interface, installation, operation and maintenance are quite simple. Many manufacturers, however, are now striving to achieve on-line closed loop control, in these cases the benefit of obtaining continuous measurement is well worth the effort required to automate the analysis. PMID:18924898

  1. Automating the weaning process with advanced closed-loop systems.

    PubMed

    Burns, Karen E A; Lellouche, Francois; Lessard, Martin R

    2008-10-01

    Limiting the duration of invasive ventilation is an important goal in caring for critically ill patients. Several clinical trials have shown that compared to traditional care, protocols can reduce the total duration of mechanical ventilation. Computerized or automated weaning has the potential to improve weaning, while decreasing associated workload, and to transfer best evidence into clinical practice by integrating closed-loop technology into protocols that can be operationalized continuously. In this article, we review the principles of automated systems, discuss automated systems that can be used during weaning, and examine the best-current evidence from randomized trials and observational studies supporting their use. We highlight three commercially available systems (Mandatory Minute Ventilation, Adaptive Support Ventilation and SmartCare) that can be used to automate the weaning process. We note advantages and disadvantages associated with individual weaning systems and differences among them. We discuss the potential role for automation in complimenting clinical acumen, reducing practice pattern variation and facilitating knowledge translation into clinical practice, and underscore the need for additional high quality investigations to evaluate automated weaning systems in different practice settings and diverse patient populations.

  2. Use of Microdialysis-Based Continuous Glucose Monitoring to Drive Real-Time Semi-Closed-Loop Insulin Infusion

    PubMed Central

    Freckmann, Guido; Jendrike, Nina; Buck, Harvey; Bousamra, Steven; Galley, Paul; Thukral, Ajay; Wagner, Robin; Weinert, Stefan; Haug, Cornelia

    2014-01-01

    Continuous glucose monitoring (CGM) and automated insulin delivery may make diabetes management substantially easier, if the quality of the resulting therapy remains adequate. In this study, a semi-closed-loop control algorithm was used to drive insulin therapy and its quality was compared to that of subject-directed therapy. Twelve subjects stayed at the study site for approximately 70 hours and were provided with the investigational Automated Pancreas System Test Stand (APS-TS), which was used to calculate insulin dosage recommendations automatically. These recommendations were based on microdialysis CGM values and common diabetes therapy parameters. For the first half of their stay, the subjects directed their diabetes therapy themselves, whereas for the second half, the insulin recommendations were delivered by the APS-TS (so-called algorithm-driven therapy). During subject-directed therapy, the mean glucose was 114 mg/dl compared to 125 mg/dl during algorithm-driven therapy. Time in target (90 to 150 mg/dl) was approximately 46% during subject-directed therapy and approximately 58% during algorithm-driven therapy. When subjects directed their therapy, approximately 2 times more hypoglycemia interventions (oral administration of carbohydrates) were required than during algorithm-driven therapy. No hyperglycemia interventions (delivery of addition insulin) were necessary during subject-directed therapy, while during algorithm-driven therapy, 2 hyperglycemia interventions were necessary. The APS-TS was able to adequately control glucose concentrations in the subjects. Time in target was at least comparable or moderately higher during closed-loop control and markedly fewer hypoglycemia interventions were required, thus increasing patient safety. PMID:25205589

  3. An Internet Protocol-Based Software System for Real-Time, Closed-Loop, Multi-Spacecraft Mission Simulation Applications

    NASA Technical Reports Server (NTRS)

    Burns, Richard D.; Davis, George; Cary, Everett; Higinbotham, John; Hogie, Keith

    2003-01-01

    A mission simulation prototype for Distributed Space Systems has been constructed using existing developmental hardware and software testbeds at NASA s Goddard Space Flight Center. A locally distributed ensemble of testbeds, connected through the local area network, operates in real time and demonstrates the potential to assess the impact of subsystem level modifications on system level performance and, ultimately, on the quality and quantity of the end product science data.

  4. An Internet Protocol-Based Software System for Real-Time, Closed-Loop, Multi-Spacecraft Mission Simulation Applications

    NASA Technical Reports Server (NTRS)

    Burns, Richard D.; Davis, George; Cary, Everett; Higinbotham, John; Hogie, Keith

    2003-01-01

    A mission simulation prototype for Distributed Space Systems has been constructed using existing developmental hardware and software testbeds at NASA s Goddard Space Flight Center. A locally distributed ensemble of testbeds, connected through the local area network, operates in real time and demonstrates the potential to assess the impact of subsystem level modifications on system level performance and, ultimately, on the quality and quantity of the end product science data.

  5. Closed loop control of the induction heating process using miniature magnetic sensors

    DOEpatents

    Bentley, Anthony E.; Kelley, John Bruce; Zutavern, Fred J.

    2003-05-20

    A method and system for providing real-time, closed-loop control of the induction hardening process. A miniature magnetic sensor located near the outer surface of the workpiece measures changes in the surface magnetic field caused by changes in the magnetic properties of the workpiece as it heats up during induction heating (or cools down during quenching). A passive miniature magnetic sensor detects a distinct magnetic spike that appears when the saturation field, B.sub.sat, of the workpiece has been exceeded. This distinct magnetic spike disappears when the workpiece's surface temperature exceeds its Curie temperature, due to the sudden decrease in its magnetic permeability. Alternatively, an active magnetic sensor can measure changes in the resonance response of the monitor coil when the excitation coil is linearly swept over 0-10 MHz, due to changes in the magnetic permeability and electrical resistivity of the workpiece as its temperature increases (or decreases).

  6. An Internet Protocol-Based Software System for Real-Time, Closed-Loop, Multi-Spacecraft Mission Simulation Applications

    NASA Technical Reports Server (NTRS)

    Davis, George; Cary, Everett; Higinbotham, John; Burns, Richard; Hogie, Keith; Hallahan, Francis

    2003-01-01

    The paper will provide an overview of the web-based distributed simulation software system developed for end-to-end, multi-spacecraft mission design, analysis, and test at the NASA Goddard Space Flight Center (GSFC). This software system was developed for an internal research and development (IR&D) activity at GSFC called the Distributed Space Systems (DSS) Distributed Synthesis Environment (DSE). The long-term goal of the DSS-DSE is to integrate existing GSFC stand-alone test beds, models, and simulation systems to create a "hands on", end-to-end simulation environment for mission design, trade studies and simulations. The short-term goal of the DSE was therefore to develop the system architecture, and then to prototype the core software simulation capability based on a distributed computing approach, with demonstrations of some key capabilities by the end of Fiscal Year 2002 (FY02). To achieve the DSS-DSE IR&D objective, the team adopted a reference model and mission upon which FY02 capabilities were developed. The software was prototyped according to the reference model, and demonstrations were conducted for the reference mission to validate interfaces, concepts, etc. The reference model, illustrated in Fig. 1, included both space and ground elements, with functional capabilities such as spacecraft dynamics and control, science data collection, space-to-space and space-to-ground communications, mission operations, science operations, and data processing, archival and distribution addressed.

  7. An Internet Protocol-Based Software System for Real-Time, Closed-Loop, Multi-Spacecraft Mission Simulation Applications

    NASA Technical Reports Server (NTRS)

    Davis, George; Cary, Everett; Higinbotham, John; Burns, Richard; Hogie, Keith; Hallahan, Francis

    2003-01-01

    The paper will provide an overview of the web-based distributed simulation software system developed for end-to-end, multi-spacecraft mission design, analysis, and test at the NASA Goddard Space Flight Center (GSFC). This software system was developed for an internal research and development (IR&D) activity at GSFC called the Distributed Space Systems (DSS) Distributed Synthesis Environment (DSE). The long-term goal of the DSS-DSE is to integrate existing GSFC stand-alone test beds, models, and simulation systems to create a "hands on", end-to-end simulation environment for mission design, trade studies and simulations. The short-term goal of the DSE was therefore to develop the system architecture, and then to prototype the core software simulation capability based on a distributed computing approach, with demonstrations of some key capabilities by the end of Fiscal Year 2002 (FY02). To achieve the DSS-DSE IR&D objective, the team adopted a reference model and mission upon which FY02 capabilities were developed. The software was prototyped according to the reference model, and demonstrations were conducted for the reference mission to validate interfaces, concepts, etc. The reference model, illustrated in Fig. 1, included both space and ground elements, with functional capabilities such as spacecraft dynamics and control, science data collection, space-to-space and space-to-ground communications, mission operations, science operations, and data processing, archival and distribution addressed.

  8. Closed-Loop Real-Time Imaging Enables Fully Automated Cell-Targeted Patch-Clamp Neural Recording In Vivo.

    PubMed

    Suk, Ho-Jun; van Welie, Ingrid; Kodandaramaiah, Suhasa B; Allen, Brian; Forest, Craig R; Boyden, Edward S

    2017-08-30

    Targeted patch-clamp recording is a powerful method for characterizing visually identified cells in intact neural circuits, but it requires skill to perform. We previously developed an algorithm that automates "blind" patching in vivo, but full automation of visually guided, targeted in vivo patching has not been demonstrated, with currently available approaches requiring human intervention to compensate for cell movement as a patch pipette approaches a targeted neuron. Here we present a closed-loop real-time imaging strategy that automatically compensates for cell movement by tracking cell position and adjusting pipette motion while approaching a target. We demonstrate our system's ability to adaptively patch, under continuous two-photon imaging and real-time analysis, fluorophore-expressing neurons of multiple types in the living mouse cortex, without human intervention, with yields comparable to skilled human experimenters. Our "imagepatching" robot is easy to implement and will help enable scalable characterization of identified cell types in intact neural circuits. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. A closed loop process for recycling spent lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Gratz, Eric; Sa, Qina; Apelian, Diran; Wang, Yan

    2014-09-01

    As lithium ion (Li-ion) batteries continue to increase their market share, recycling Li-ion batteries will become mandatory due to limited resources. We have previously demonstrated a new low temperature methodology to separate and synthesize cathode materials from mixed cathode materials. In this study we take used Li-ion batteries from a recycling source and recover active cathode materials, copper, steel, etc. To accomplish this the batteries are shredded and processed to separate the steel, copper and cathode materials; the cathode materials are then leached into solution; the concentrations of nickel, manganese and cobalt ions are adjusted so NixMnyCoz(OH)2 is precipitated. The precipitated product can then be reacted with lithium carbonate to form LiNixMnyCozO2. The results show that the developed recycling process is practical with high recovery efficiencies (∼90%), and 1 ton of Li-ion batteries has the potential to generate 5013 profit margin based on materials balance.

  10. Real-Time Nonlinear Optical Information Processing.

    DTIC Science & Technology

    1979-06-01

    operations aree presented. One approach realizes the halftone method of nonlinear optical processing in real time by replacing the conventional...photographic recording medium with a real-time image transducer. In the second approach halftoning is eliminated and the real-time device is used directly

  11. Gas powered, closed loop power system and process for using same

    SciTech Connect

    Cardone, J.T.; Dill, J.M.; Shatz, K.J.

    1982-06-08

    This invention relates to a gas powered, closed loop power generating system which generates power substantially as a result of the flow of gas through its power generating means. Gas flows through the power generating means because of a pressure drop caused by dissolving the gas in a solvent medium on the exit side of the power generating means. The solution is then separated into the solvent medium, and the gas. The gas pressure is raised and it is then fed back into the power generating means while the separated solvent medium is recycled to redissolve more exiting gas. A process for generating power is also disclosed.

  12. Nonlinear Real-Time Optical Signal Processing.

    DTIC Science & Technology

    1984-10-01

    DTIC ELECTE I B IIMAGE PROCESSING INSTITUTE 84 11 26 107 UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE (When Dota Entered), REPORT DOCUMENTATION...30, 1984 N NONLINEAR REAL-TIME OPTICAL SIGNAL PROCESSING i E~ A.A. Sawchuk, Principal Investigator T.C. Strand and A.R. Tanguay. Jr. October 1, 1984...RDepartment of Electrical Engineering Image Processing institute University of Southern California University Park-MC 0272 Los Angeles, California

  13. Nonlinear Real-Time Optical Signal Processing.

    DTIC Science & Technology

    1981-06-30

    bandwidth and space-bandwidth products. Real-time homonorphic and loga- rithmic filtering by halftone nonlinear processing has been achieved. A...Page ABSTRACT 1 1. RESEARCH OBJECTIVES AND PROGRESS 3 I-- 1.1 Introduction and Project overview 3 1.2 Halftone Processing 9 1.3 Direct Nonlinear...time homomorphic and logarithmic filtering by halftone nonlinear processing has been achieved. A detailed analysis of degradation due to the finite gamma

  14. Closed-looped in situ nano processing on a culturing cell using an inverted electron beam lithography system

    SciTech Connect

    Hoshino, Takayuki; Mabuchi, Kunihiko

    2013-03-08

    Highlights: ► An electron beam lithography (EBL) was used as an in situ nano processing for a living cell. ► A synchronized optics was containing an inverted EBL and an optical microscope. ► This system visualized real-time images of the EB-induced nano processing. ► We demonstrated the nano processing for a culturing cell with 200–300 nm resolution. ► Our system would be able to provide high resolution display of virtual environments. -- Abstract: The beam profile of an electron beam (EB) can be focused onto less than a nanometer spot and scanned over a wide field with extremely high speed sweeping. Thus, EB is employed for nano scale lithography in applied physics research studies and in fabrication of semiconductors. We applied a scanning EB as a control system for a living cell membrane which is representative of large scale complex systems containing nanometer size components. First, we designed the opposed co-axial dual optics containing inverted electron beam lithography (I-EBL) system and a fluorescent optical microscope. This system could provide in situ nano processing for a culturing living cell on a 100-nm-thick SiN nanomembrane, which was placed between the I-EBL and the fluorescent optical microscope. Then we demonstrated the EB-induced chemical direct nano processing for a culturing cell with hundreds of nanometer resolution and visualized real-time images of the scanning spot of the EB-induced luminescent emission and chemical processing using a high sensitive camera mounted on the optical microscope. We concluded that our closed-loop in situ nano processing would be able to provide a nanometer resolution display of virtual molecule environments to study functional changes of bio-molecule systems.

  15. Real-time optical image processing techniques

    NASA Technical Reports Server (NTRS)

    Liu, Hua-Kuang

    1988-01-01

    Nonlinear real-time optical processing on spatial pulse frequency modulation has been pursued through the analysis, design, and fabrication of pulse frequency modulated halftone screens and the modification of micro-channel spatial light modulators (MSLMs). Micro-channel spatial light modulators are modified via the Fabry-Perot method to achieve the high gamma operation required for non-linear operation. Real-time nonlinear processing was performed using the halftone screen and MSLM. The experiments showed the effectiveness of the thresholding and also showed the needs of higher SBP for image processing. The Hughes LCLV has been characterized and found to yield high gamma (about 1.7) when operated in low frequency and low bias mode. Cascading of two LCLVs should also provide enough gamma for nonlinear processing. In this case, the SBP of the LCLV is sufficient but the uniformity of the LCLV needs improvement. These include image correlation, computer generation of holograms, pseudo-color image encoding for image enhancement, and associative-retrieval in neural processing. The discovery of the only known optical method for dynamic range compression of an input image in real-time by using GaAs photorefractive crystals is reported. Finally, a new architecture for non-linear multiple sensory, neural processing has been suggested.

  16. Real-time optical image processing techniques

    NASA Astrophysics Data System (ADS)

    Liu, Hua-Kuang

    1988-10-01

    Nonlinear real-time optical processing on spatial pulse frequency modulation has been pursued through the analysis, design, and fabrication of pulse frequency modulated halftone screens and the modification of micro-channel spatial light modulators (MSLMs). Micro-channel spatial light modulators are modified via the Fabry-Perot method to achieve the high gamma operation required for non-linear operation. Real-time nonlinear processing was performed using the halftone screen and MSLM. The experiments showed the effectiveness of the thresholding and also showed the needs of higher SBP for image processing. The Hughes LCLV has been characterized and found to yield high gamma (about 1.7) when operated in low frequency and low bias mode. Cascading of two LCLVs should also provide enough gamma for nonlinear processing. In this case, the SBP of the LCLV is sufficient but the uniformity of the LCLV needs improvement. These include image correlation, computer generation of holograms, pseudo-color image encoding for image enhancement, and associative-retrieval in neural processing. The discovery of the only known optical method for dynamic range compression of an input image in real-time by using GaAs photorefractive crystals is reported. Finally, a new architecture for non-linear multiple sensory, neural processing has been suggested.

  17. A Hybrid Functional Electrical Stimulation for Real-Time Estimation of Joint Torque and Closed-Loop Control of Muscle Activation

    PubMed Central

    Li, Zhan; Guiraud, David; Andreu, David; Fattal, Charles; Gelis, Anthony; Hayashibe, Mitsuhiro

    2016-01-01

    As a neuroprosthetic technique, functional electrical stimulation (FES) can restore lost motor performance of impaired patients. Through delivering electrical pulses to target muscles, the joint movement can be eventually elicited. This work presents a real-time FES system which is able to deal with two neuroprosthetic missions: one is estimating FES-induced joint torque with evoked electromyograph (eEMG), and the other is artificially controlling muscle activation with such eEMG feedback. The clinical experiment results on spinal cord injured (SCI) patients and healthy subjects show promising performance of the proposed FES system. PMID:27990235

  18. Process step response based fractional PIλDμ controller parameters tuning for desired closed loop response

    NASA Astrophysics Data System (ADS)

    Fergani, Nadir; Charef, Abdelfatah

    2016-02-01

    In this paper, a tuning method of the fractional PIλDμ controllers for classical feedback control systems is proposed. The PIλDμ controller design strategy is drawn up such that the closed loop system is equivalent to a desired fractional order model whose transfer function is Bode's ideal function ?, a widely used function in the fractional order control domain because of its iso-damping property which is an important robustness feature. In this tuning technique, the values of the five parameters of the fractional PIλDμ controller are derived analytically using only the step response of a stable process without requirement of its model. The derived formulations of the tuning technique are presented. Illustrative examples are given to test the effectiveness and the usefulness of the proposed PIλDμ controller tuning approach.

  19. Autonomous Closed-Loop Tasking, Acquisition, Processing, and Evaluation for Situational Awareness Feedback

    NASA Technical Reports Server (NTRS)

    Frye, Stuart; Mandl, Dan; Cappelaere, Pat

    2016-01-01

    This presentation describes the closed loop satellite autonomy methods used to connect users and the assets on Earth Orbiter- 1 (EO-1) and similar satellites. The base layer is a distributed architecture based on Goddard Mission Services Evolution Concept (GMSEC) thus each asset still under independent control. Situational awareness is provided by a middleware layer through common Application Programmer Interface (API) to GMSEC components developed at GSFC. Users setup their own tasking requests, receive views into immediate past acquisitions in their area of interest, and into future feasibilities for acquisition across all assets. Automated notifications via pubsub feeds are returned to users containing published links to image footprints, algorithm results, and full data sets. Theme-based algorithms are available on-demand for processing.

  20. Real-time video image processing

    NASA Astrophysics Data System (ADS)

    Smedley, Kirk G.; Yool, Stephen R.

    1990-11-01

    Lockheed has designed and implemented a prototype real-time Video Enhancement Workbench (VEW) using commercial offtheshelf hardware and custom software. The hardware components include a Sun workstation Aspex PIPE image processor time base corrector VCR video camera and realtime disk subsystem. A cornprehensive set of image processing functions can be invoked by the analyst at any time during processing enabling interactive enhancement and exploitation of video sequences. Processed images can be transmitted and stored within the system in digital or video form. VEW also provides image output to a laser printer and to Interleaf technical publishing software.

  1. High-density microelectrode array recordings and real-time spike sorting for closed-loop experiments: an emerging technology to study neural plasticity.

    PubMed

    Franke, Felix; Jäckel, David; Dragas, Jelena; Müller, Jan; Radivojevic, Milos; Bakkum, Douglas; Hierlemann, Andreas

    2012-01-01

    Understanding plasticity of neural networks is a key to comprehending their development and function. A powerful technique to study neural plasticity includes recording and control of pre- and post-synaptic neural activity, e.g., by using simultaneous intracellular recording and stimulation of several neurons. Intracellular recording is, however, a demanding technique and has its limitations in that only a small number of neurons can be stimulated and recorded from at the same time. Extracellular techniques offer the possibility to simultaneously record from larger numbers of neurons with relative ease, at the expenses of increased efforts to sort out single neuronal activities from the recorded mixture, which is a time consuming and error prone step, referred to as spike sorting. In this mini-review, we describe recent technological developments in two separate fields, namely CMOS-based high-density microelectrode arrays, which also allow for extracellular stimulation of neurons, and real-time spike sorting. We argue that these techniques, when combined, will provide a powerful tool to study plasticity in neural networks consisting of several thousand neurons in vitro.

  2. Reconfigurable real-time distributed processing network

    NASA Astrophysics Data System (ADS)

    Page, S. F.; Seely, R. D.; Hickman, D.

    2011-06-01

    This paper describes a novel real-time image and signal processing network, RONINTM, which facilitates the rapid design and deployment of systems providing advanced geospatial surveillance and situational awareness capability. RONINTM is a distributed software architecture consisting of multiple agents or nodes, which can be configured to implement a variety of state-of-the-art computer vision and signal processing algorithms. The nodes operate in an asynchronous fashion and can run on a variety of hardware platforms, thus providing a great deal of scalability and flexibility. Complex algorithmic configuration chains can be assembled using an intuitive graphical interface in a plug-and- play manner. RONINTM has been successfully exploited for a number of applications, ranging from remote event detection to complex multiple-camera real-time 3D object reconstruction. This paper describes the motivation behind the creation of the network, the core design features, and presents details of an example application. Finally, the on-going development of the network is discussed, which is focussed on dynamic network reconfiguration. This allows to the network to automatically adapt itself to node or communications failure by intelligently re-routing network communications and through adaptive resource management.

  3. The role of feed-forward and feedback processes for closed-loop prosthesis control

    PubMed Central

    2011-01-01

    Background It is widely believed that both feed-forward and feed-back mechanisms are required for successful object manipulation. Open-loop upper-limb prosthesis wearers receive no tactile feedback, which may be the cause of their limited dexterity and compromised grip force control. In this paper we ask whether observed prosthesis control impairments are due to lack of feedback or due to inadequate feed-forward control. Methods Healthy subjects were fitted with a closed-loop robotic hand and instructed to grasp and lift objects of different weights as we recorded trajectories and force profiles. We conducted three experiments under different feed-forward and feed-back configurations to elucidate the role of tactile feedback (i) in ideal conditions, (ii) under sensory deprivation, and (iii) under feed-forward uncertainty. Results (i) We found that subjects formed economical grasps in ideal conditions. (ii) To our surprise, this ability was preserved even when visual and tactile feedback were removed. (iii) When we introduced uncertainty into the hand controller performance degraded significantly in the absence of either visual or tactile feedback. Greatest performance was achieved when both sources of feedback were present. Conclusions We have introduced a novel method to understand the cognitive processes underlying grasping and lifting. We have shown quantitatively that tactile feedback can significantly improve performance in the presence of feed-forward uncertainty. However, our results indicate that feed-forward and feed-back mechanisms serve complementary roles, suggesting that to improve on the state-of-the-art in prosthetic hands we must develop prostheses that empower users to correct for the inevitable uncertainty in their feed-forward control. PMID:22032545

  4. OPAD-EDIFIS Real-Time Processing

    NASA Technical Reports Server (NTRS)

    Katsinis, Constantine

    1997-01-01

    The Optical Plume Anomaly Detection (OPAD) detects engine hardware degradation of flight vehicles through identification and quantification of elemental species found in the plume by analyzing the plume emission spectra in a real-time mode. Real-time performance of OPAD relies on extensive software which must report metal amounts in the plume faster than once every 0.5 sec. OPAD software previously written by NASA scientists performed most necessary functions at speeds which were far below what is needed for real-time operation. The research presented in this report improved the execution speed of the software by optimizing the code without changing the algorithms and converting it into a parallelized form which is executed in a shared-memory multiprocessor system. The resulting code was subjected to extensive timing analysis. The report also provides suggestions for further performance improvement by (1) identifying areas of algorithm optimization, (2) recommending commercially available multiprocessor architectures and operating systems to support real-time execution and (3) presenting an initial study of fault-tolerance requirements.

  5. Driving Sleep Slow Oscillations by Auditory Closed-Loop Stimulation—A Self-Limiting Process

    PubMed Central

    Ngo, Hong-Viet V.; Miedema, Arjan; Faude, Isabel; Martinetz, Thomas; Mölle, Matthias

    2015-01-01

    The <1 Hz EEG slow oscillation (SO) is a hallmark of slow-wave sleep (SWS) and is critically involved in sleep-associated memory formation. Previous studies showed that SOs and associated memory function can be effectively enhanced by closed-loop auditory stimulation, when clicks are presented in synchrony with upcoming SO up states. However, increasing SOs and synchronized excitability also bear the risk of emerging seizure activity, suggesting the presence of mechanisms in the healthy brain that counter developing hypersynchronicity during SOs. Here, we aimed to test the limits of driving SOs through closed-loop auditory stimulation in healthy humans. Study I tested a “Driving stimulation” protocol (vs “Sham”) in which trains of clicks were presented in synchrony with SO up states basically as long as an ongoing SO train was identified on-line. Study II compared Driving stimulation with a “2-Click” protocol where the maximum of stimuli delivered in a train was limited to two clicks. Stimulation was applied during SWS in the first 210 min of nocturnal sleep. Before and after sleep declarative word-pair memories were tested. Compared with the Sham control, Driving stimulation prolonged SO trains and enhanced SO amplitudes, phase-locked spindle activity, and overnight retention of word pairs (all ps < 0.05). Importantly, effects of Driving stimulation did not exceed those of 2-Click stimulation (p > 0.180), indicating the presence of a mechanism preventing the development of hypersynchronicity during SO activity. Assessment of temporal dynamics revealed a rapidly fading phase-locked spindle activity during repetitive click stimulation, suggesting that spindle refractoriness contributes to this protective mechanism. PMID:25926443

  6. Driving sleep slow oscillations by auditory closed-loop stimulation-a self-limiting process.

    PubMed

    Ngo, Hong-Viet V; Miedema, Arjan; Faude, Isabel; Martinetz, Thomas; Mölle, Matthias; Born, Jan

    2015-04-29

    The <1 Hz EEG slow oscillation (SO) is a hallmark of slow-wave sleep (SWS) and is critically involved in sleep-associated memory formation. Previous studies showed that SOs and associated memory function can be effectively enhanced by closed-loop auditory stimulation, when clicks are presented in synchrony with upcoming SO up states. However, increasing SOs and synchronized excitability also bear the risk of emerging seizure activity, suggesting the presence of mechanisms in the healthy brain that counter developing hypersynchronicity during SOs. Here, we aimed to test the limits of driving SOs through closed-loop auditory stimulation in healthy humans. Study I tested a "Driving stimulation" protocol (vs "Sham") in which trains of clicks were presented in synchrony with SO up states basically as long as an ongoing SO train was identified on-line. Study II compared Driving stimulation with a "2-Click" protocol where the maximum of stimuli delivered in a train was limited to two clicks. Stimulation was applied during SWS in the first 210 min of nocturnal sleep. Before and after sleep declarative word-pair memories were tested. Compared with the Sham control, Driving stimulation prolonged SO trains and enhanced SO amplitudes, phase-locked spindle activity, and overnight retention of word pairs (all ps < 0.05). Importantly, effects of Driving stimulation did not exceed those of 2-Click stimulation (p > 0.180), indicating the presence of a mechanism preventing the development of hypersynchronicity during SO activity. Assessment of temporal dynamics revealed a rapidly fading phase-locked spindle activity during repetitive click stimulation, suggesting that spindle refractoriness contributes to this protective mechanism.

  7. [Closed-loop blood transfusion management system based on PDA].

    PubMed

    Chen, Yiyi; Chen, Canda; Luo, Luo; Yin, Zhou; Zhou, Min; Xie, Qiong; Xu, Min; Zhang, Qiutao

    2013-09-01

    A closed-loop transfusion management system is constructed that covers blood preservation, transportation, transfer, distribution of blood, distribution, clinical blood specimen collection and blood transfusion process, which can monitor the implementation of doctor's advice, view the transport process of blood and blood samples, and record blood transfusion and adverse reaction information. These measurements can play a good effect in reduction of manual records and handover links in blood transfusion management, enhance the blood bank management, guarantee safely using blood, and realize the goal of real-time monitoring and closed-loop management.

  8. Neural signal processing and closed-loop control algorithm design for an implanted neural recording and stimulation system.

    PubMed

    Hamilton, Lei; McConley, Marc; Angermueller, Kai; Goldberg, David; Corba, Massimiliano; Kim, Louis; Moran, James; Parks, Philip D; Sang Chin; Widge, Alik S; Dougherty, Darin D; Eskandar, Emad N

    2015-08-01

    A fully autonomous intracranial device is built to continually record neural activities in different parts of the brain, process these sampled signals, decode features that correlate to behaviors and neuropsychiatric states, and use these features to deliver brain stimulation in a closed-loop fashion. In this paper, we describe the sampling and stimulation aspects of such a device. We first describe the signal processing algorithms of two unsupervised spike sorting methods. Next, we describe the LFP time-frequency analysis and feature derivation from the two spike sorting methods. Spike sorting includes a novel approach to constructing a dictionary learning algorithm in a Compressed Sensing (CS) framework. We present a joint prediction scheme to determine the class of neural spikes in the dictionary learning framework; and, the second approach is a modified OSort algorithm which is implemented in a distributed system optimized for power efficiency. Furthermore, sorted spikes and time-frequency analysis of LFP signals can be used to generate derived features (including cross-frequency coupling, spike-field coupling). We then show how these derived features can be used in the design and development of novel decode and closed-loop control algorithms that are optimized to apply deep brain stimulation based on a patient's neuropsychiatric state. For the control algorithm, we define the state vector as representative of a patient's impulsivity, avoidance, inhibition, etc. Controller parameters are optimized to apply stimulation based on the state vector's current state as well as its historical values. The overall algorithm and software design for our implantable neural recording and stimulation system uses an innovative, adaptable, and reprogrammable architecture that enables advancement of the state-of-the-art in closed-loop neural control while also meeting the challenges of system power constraints and concurrent development with ongoing scientific research designed

  9. Real-time process/quality control for HPC processing.

    PubMed

    Arpagaus, M; Leibundgut, E Oppliger; Zbären, K; Brunold, C; Ischi, E; Tobler, A; Zwicky, C

    2004-01-01

    JACIE Standards (FACT Standards in the USA) have been implemented in Europe since 1999. An on-site accreditation inspection took place at our center in January 2004. The purpose of this work was to develop a real-time process/quality control system meeting the JACIE Standards for HPC release. Data from 194 HPC processing procedures for autologous transplantation performed over a 5-year period were analyzed. The results of different processing methods applied at our facility were compared: (1) cryopreservation without washing cells (n=50), (2) washing cells (n=87), (3) cell-density separation (n=12) and (4) positive CD34 selection (n=45). Four critical control points were set for the validation of HPC processing: (a) number of lost CD34(+) cells during processing, (b) contamination, (c) viability of the cells after thawing and (d) ability to reconstitute hematopoiesis after transplantation. On the basis of statistical analysis, ranges of acceptable values were defined for each critical control point and for each processing method. Those acceptable values were used for cell release and real-time quality control. This study describes a model for the validation of HPC processing and for a real-time process/quality control system for HPC release. Optimization of processing techniques, standardization of methods and comparison between facilities will open the way towards external quality controls and quality improvement.

  10. Nonlinear Real-Time Optical Signal Processing

    DTIC Science & Technology

    1990-09-01

    pattern recognition. Additional work concerns the relationship of parallel computation paradigms to optical computing and halftone screen techniques...paradigms to optical computing and halftone screen techniques for implementing general nonlinear functions. 3\\ 2 Research Progress This section...Vol. 23, No. 8, pp. 34-57, 1986. 2.4 Nonlinear Optical Processing with Halftones : Degradation and Compen- sation Models This paper is concerned with

  11. Algorithms for Real-Time Processing

    DTIC Science & Technology

    2003-04-01

    algorithm has been mapped on an application specific prototyping platform which contains four VLSI CORDIC ASICs and some FPGAs (Field Programmable Gate... makes less critical the implementation of a VLSI based systolic array. A practical application of systolic processing for classical ground based or ship...interferometry (ATI) - SAR to detect moving targets [ 18]. It can be shown that this approach offers a considerable computational advantage; FPGA technology has

  12. Vector processing enhancements for real-time image analysis.

    SciTech Connect

    Shoaf, S.; APS Engineering Support Division

    2008-01-01

    A real-time image analysis system was developed for beam imaging diagnostics. An Apple Power Mac G5 with an Active Silicon LFG frame grabber was used to capture video images that were processed and analyzed. Software routines were created to utilize vector-processing hardware to reduce the time to process images as compared to conventional methods. These improvements allow for more advanced image processing diagnostics to be performed in real time.

  13. A fuzzy cost-benefit function to select economical products for processing in a closed-loop supply chain

    NASA Astrophysics Data System (ADS)

    Pochampally, Kishore K.; Gupta, Surendra M.; Cullinane, Thomas P.

    2004-02-01

    The cost-benefit analysis of data associated with re-processing of used products often involves the uncertainty feature of cash-flow modeling. The data is not objective because of uncertainties in supply, quality and disassembly times of used products. Hence, decision-makers must rely on "fuzzy" data for analysis. The same parties that are involved in the forward supply chain often carry out the collection and re-processing of used products. It is therefore important that the cost-benefit analysis takes the data of both new products and used products into account. In this paper, a fuzzy cost-benefit function is proposed that is used to perform a multi-criteria economic analysis to select the most economical products to process in a closed-loop supply chain. Application of the function is detailed through an illustrative example.

  14. Dynamic Modeling of Process Technologies for Closed-Loop Water Recovery Systems

    NASA Technical Reports Server (NTRS)

    Allada, Rama Kumar; Lange, Kevin E.; Anderson, Molly S.

    2012-01-01

    Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents dynamic simulations of chemical process for primary processor technologies including: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system, the Wiped-Film Rotating Disk (WFRD), and post-distillation water polishing processes such as the Volatiles Removal Assembly (VRA). These dynamic models were developed using the Aspen Custom Modeler (Registered TradeMark) and Aspen Plus(Registered TradeMark) process simulation tools. The results expand upon previous work for water recovery technology models and emphasize dynamic process modeling and results. The paper discusses system design, modeling details, and model results for each technology and presents some comparisons between the model results and available test data. Following these initial comparisons, some general conclusions and forward work are discussed.

  15. Dynamic Modeling of Process Technologies for Closed-Loop Water Recovery Systems

    NASA Technical Reports Server (NTRS)

    Allada, Rama Kumar; Lange, Kevin; Anderson, Molly

    2011-01-01

    Detailed chemical process simulations are a useful tool in designing and optimizing complex systems and architectures for human life support. Dynamic and steady-state models of these systems help contrast the interactions of various operating parameters and hardware designs, which become extremely useful in trade-study analyses. NASA s Exploration Life Support technology development project recently made use of such models to compliment a series of tests on different waste water distillation systems. This paper presents dynamic simulations of chemical process for primary processor technologies including: the Cascade Distillation System (CDS), the Vapor Compression Distillation (VCD) system, the Wiped-Film Rotating Disk (WFRD), and post-distillation water polishing processes such as the Volatiles Removal Assembly (VRA) that were developed using the Aspen Custom Modeler and Aspen Plus process simulation tools. The results expand upon previous work for water recovery technology models and emphasize dynamic process modeling and results. The paper discusses system design, modeling details, and model results for each technology and presents some comparisons between the model results and available test data. Following these initial comparisons, some general conclusions and forward work are discussed.

  16. In situ heat treatment process utilizing a closed loop heating system

    SciTech Connect

    Vinegar, Harold J.; Nguyen, Scott Vinh

    2010-12-07

    Systems and methods for an in situ heat treatment process that utilizes a circulation system to heat one or more treatment areas are described herein. The circulation system may use a heated liquid heat transfer fluid that passes through piping in the formation to transfer heat to the formation. In some embodiments, the piping may be positioned in at least two of the wellbores.

  17. Application of knowledge-based vision to closed-loop control of the injection molding process

    NASA Astrophysics Data System (ADS)

    Marsh, Robert; Stamp, R. J.; Hill, T. M.

    1997-10-01

    An investigation is under way to develop a control system for an industrial process which uses a vision systems as a sensor. The research is aimed at the improvement of product quality in commercial injection molding system. A significant enhancement has been achieved in the level of application of visually based inspection techniques to component quality. The aim of the research has been the investigation, and employment, of inspection methods that use knowledge based machine vision. The application of such techniques in this context is comprehensive, extending from object oriented analysis, design and programming of the inspection program, to the application of rule based reasoning, to image interpretation, vision system diagnostics, component diagnostics and molding machine control. In this way, knowledge handling methods are exploited wherever they prove to be beneficial. The vision knowledge base contains information on the procedures required to achieve successful identification of component surface defects. A collection of image processing and pattern recognition algorithms are applied selectively. Once inspection of the component has been performed, defects are related to process variables which affect the quality of the component, and another knowledge base is used to effect a control action at the molding machine. Feedback from other machine sensor is also used to direct the control procedure. Results from the knowledge based vision inspection system are encouraging. They indicate that rapid and effective fault detection and analysis is feasible, as is the verification of system integrity.

  18. Closed loop control of the multi-column solvent gradient purification process.

    PubMed

    Krättli, M; Ströhlein, G; Aumann, L; Müller-Späth, T; Morbidelli, M

    2011-12-16

    A PID controller able to support the operator in the operation of the Multi-column Countercurrent Solvent Gradient Purification (MCSGP) process which is a continuous, countercurrent chromatographic process has been developed. As measurement, only the online UV signals at each column outlet are used. This guarantees a simple and cheap control implementation and a fast control action. Accordingly, the controller does not guarantee any purity or yield value, but simply that the withdrawn window of the product is centered in a specific region of the UV chromatogram where the purity specifications are expected to be satisfied. This can be determined by the operator based on the batch chromatogram selected for designing the MCSGP operating conditions. Thus the controller provides a reliable and efficient tool for the operator to run properly a MCSGP unit in combination with suitable offline analytics for the quantification of purity and yield. The applications are discussed involving the purification of a model protein and a peptide. It is shown that the developed controller is effective in driving the unit to steady state during start up and in keeping a stable steady state while rejecting external disturbances. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Real-time signal processing with FPS array processors

    SciTech Connect

    Higginbotham, R.E.; Wiley, P.G.

    1980-01-01

    The authors discuss real-time signal processing with the FPS programmable array processor (AP). This AP is designed to attach as a peripheral device to a host machine, either a minicomputer or mainframe. The basic AP consists of a host interface, multiple independent memories, parallel pipelined floating-point adder and multiplier, and a control/integer processing unit. For real-time signal processing applications in which the throughput rate exceeds the capability of the host computer, independent input/output (I/O) interfaces are available which provide direct access to the AP for external input and output devices. 2 references.

  20. Lithium Carbonate Recovery from Cathode Scrap of Spent Lithium-Ion Battery: A Closed-Loop Process.

    PubMed

    Gao, Wenfang; Zhang, Xihua; Zheng, Xiaohong; Lin, Xiao; Cao, Hongbin; Zhang, Yi; Sun, Zhi

    2017-02-07

    A closed-loop process to recover lithium carbonate from cathode scrap of lithium-ion battery (LIB) is developed. Lithium could be selectively leached into solution using formic acid while aluminum remained as the metallic form, and most of the other metals from the cathode scrap could be precipitated out. This phenomenon clearly demonstrates that formic acid can be used for lithium recovery from cathode scrap, as both leaching and separation reagent. By investigating the effects of different parameters including temperature, formic acid concentration, H2O2 amount, and solid to liquid ratio, the leaching rate of Li can reach 99.93% with minor Al loss into the solution. Subsequently, the leaching kinetics was evaluated and the controlling step as well as the apparent activation energy could be determined. After further separation of the remaining Ni, Co, and Mn from the leachate, Li2CO3 with the purity of 99.90% could be obtained. The final solution after lithium carbonate extraction can be further processed for sodium formate preparation, and Ni, Co, and Mn precipitates are ready for precursor preparation for cathode materials. As a result, the global recovery rates of Al, Li, Ni, Co, and Mn in this process were found to be 95.46%, 98.22%, 99.96%, 99.96%, and 99.95% respectively, achieving effective resources recycling from cathode scrap of spent LIB.

  1. Closed-loop active optical system control

    NASA Astrophysics Data System (ADS)

    Sparks, T. E.

    1980-01-01

    A control system, based on a real-time lateral shear interferometer has been developed for use in control during thermal tests and static error compensation experiments. The minicomputer which controls the interferometer and provides its service functions also controls the active system, thereby giving flexibility to the algorithm. The minicomputer system contains 288 K bytes of memory and 15 M bytes of disk storage. The interferometer system employed is composed of the measuring head and its support electronics, a video display on which wavefront contour maps are generated, and a DECwriter operator console. The versatility provided by the use of a general purpose interferometer system allows for interactive control of the closed-loop process. Various arithmetic capabilities such as the addition of wavefronts, division by a constant, and fitting of wavefront data with Zernike polynomials, allow for measurements to be averaged and for removal of alignment errors before correction is performed.

  2. Real-time hyperspectral processing for automatic nonferrous material sorting

    NASA Astrophysics Data System (ADS)

    Picón, Artzai; Ghita, Ovidiu; Bereciartua, Aranzazu; Echazarra, Jone; Whelan, Paul F.; Iriondo, Pedro M.

    2012-01-01

    The application of hyperspectral sensors in the development of machine vision solutions has become increasingly popular as the spectral characteristics of the imaged materials are better modeled in the hyperspectral domain than in the standard trichromatic red, green, blue data. While there is no doubt that the availability of detailed spectral information is opportune as it opens the possibility to construct robust image descriptors, it also raises a substantial challenge when this high-dimensional data is used in the development of real-time machine vision systems. To alleviate the computational demand, often decorrelation techniques are commonly applied prior to feature extraction. While this approach has reduced to some extent the size of the spectral descriptor, data decorrelation alone proved insufficient in attaining real-time classification. This fact is particularly apparent when pixel-wise image descriptors are not sufficiently robust to model the spectral characteristics of the imaged materials, a case when the spatial information (or textural properties) also has to be included in the classification process. The integration of spectral and spatial information entails a substantial computational cost, and as a result the prospects of real-time operation for the developed machine vision system are compromised. To answer this requirement, in this paper we have reengineered the approach behind the integration of the spectral and spatial information in the material classification process to allow the real-time sorting of the nonferrous fractions that are contained in the waste of electric and electronic equipment scrap.

  3. An intelligent processing environment for real-time simulation

    NASA Technical Reports Server (NTRS)

    Carroll, Chester C.; Wells, Buren Earl, Jr.

    1988-01-01

    The development of a highly efficient and thus truly intelligent processing environment for real-time general purpose simulation of continuous systems is described. Such an environment can be created by mapping the simulation process directly onto the University of Alamba's OPERA architecture. To facilitate this effort, the field of continuous simulation is explored, highlighting areas in which efficiency can be improved. Areas in which parallel processing can be applied are also identified, and several general OPERA type hardware configurations that support improved simulation are investigated. Three direct execution parallel processing environments are introduced, each of which greatly improves efficiency by exploiting distinct areas of the simulation process. These suggested environments are candidate architectures around which a highly intelligent real-time simulation configuration can be developed.

  4. An architecture for real-time vision processing

    NASA Technical Reports Server (NTRS)

    Chien, Chiun-Hong

    1994-01-01

    To study the feasibility of developing an architecture for real time vision processing, a task queue server and parallel algorithms for two vision operations were designed and implemented on an i860-based Mercury Computing System 860VS array processor. The proposed architecture treats each vision function as a task or set of tasks which may be recursively divided into subtasks and processed by multiple processors coordinated by a task queue server accessible by all processors. Each idle processor subsequently fetches a task and associated data from the task queue server for processing and posts the result to shared memory for later use. Load balancing can be carried out within the processing system without the requirement for a centralized controller. The author concludes that real time vision processing cannot be achieved without both sequential and parallel vision algorithms and a good parallel vision architecture.

  5. Low-level processing for real-time image analysis

    NASA Technical Reports Server (NTRS)

    Eskenazi, R.; Wilf, J. M.

    1979-01-01

    A system that detects object outlines in television images in real time is described. A high-speed pipeline processor transforms the raw image into an edge map and a microprocessor, which is integrated into the system, clusters the edges, and represents them as chain codes. Image statistics, useful for higher level tasks such as pattern recognition, are computed by the microprocessor. Peak intensity and peak gradient values are extracted within a programmable window and are used for iris and focus control. The algorithms implemented in hardware and the pipeline processor architecture are described. The strategy for partitioning functions in the pipeline was chosen to make the implementation modular. The microprocessor interface allows flexible and adaptive control of the feature extraction process. The software algorithms for clustering edge segments, creating chain codes, and computing image statistics are also discussed. A strategy for real time image analysis that uses this system is given.

  6. Fluorescence based real time monitoring of fouling in process chromatography

    PubMed Central

    Pathak, Mili; Lintern, Katherine; Chopda, Viki; Bracewell, Daniel G.; Rathore, Anurag S.

    2017-01-01

    A real time monitoring of fouling in liquid chromatography has been presented. The versatility of the approach has been proven by successful implementation in three case studies with an error <1%. The first application demonstrates the monitoring of protein A ligand density and foulant concentration for assessing performance of protein A chromatography resin during purification of monoclonal antibodies. The observations have been supported from LC-MS/MS studies that were independently performed. The second application involves monitoring of foulant deposition during multimode cation exchange chromatography based purification of human serum albumin. Finally, in the third application, monitoring of foulants during multimodal hydrophobic interaction chromatography of recombinant human granulocyte colony stimulating factor is demonstrated. In all three cases, it is observed that the fluorescence intensity consistently increases with resin reuse as more foulants are deposited over time. The proposed approach can be readily used for real time monitoring of fouling and process control. PMID:28358349

  7. On-Board Spaceborne Real-time Digital Signal Processing

    NASA Astrophysics Data System (ADS)

    Gao, G.; Long, F.; Liu, L.

    begin center Abstract end center This paper reports a preliminary study result of an on-board digital signal processing system It consists of the on-board processing requirement analysis functional specifications and implementation with the radiation tolerant field-programmable gate array FPGA technology The FPGA program is designed in the VHDL hardware description language and implemented onto a high density F PGA chip The design takes full advantage of the massively parallel architecture of the VirtexII FPGA logic slices to achieve real-time processing at a big data rate Further more an FFT algorithm s implementation with the system is provided as an illustration

  8. Toward real-time remote processing of laparoscopic video.

    PubMed

    Ronaghi, Zahra; Duffy, Edward B; Kwartowitz, David M

    2015-10-01

    Laparoscopic surgery is a minimally invasive surgical technique where surgeons insert a small video camera into the patient's body to visualize internal organs and use small tools to perform surgical procedures. However, the benefit of small incisions has a drawback of limited visualization of subsurface tissues, which can lead to navigational challenges in the delivering of therapy. Image-guided surgery uses the images to map subsurface structures and can reduce the limitations of laparoscopic surgery. One particular laparoscopic camera system of interest is the vision system of the daVinci-Si robotic surgical system (Intuitive Surgical, Sunnyvale, California). The video streams generate approximately 360 MB of data per second, demonstrating a trend toward increased data sizes in medicine, primarily due to higher-resolution video cameras and imaging equipment. Processing this data on a bedside PC has become challenging and a high-performance computing (HPC) environment may not always be available at the point of care. To process this data on remote HPC clusters at the typical 30 frames per second (fps) rate, it is required that each 11.9 MB video frame be processed by a server and returned within 1/30th of a second. The ability to acquire, process, and visualize data in real time is essential for the performance of complex tasks as well as minimizing risk to the patient. As a result, utilizing high-speed networks to access computing clusters will lead to real-time medical image processing and improve surgical experiences by providing real-time augmented laparoscopic data. We have performed image processing algorithms on a high-definition head phantom video (1920 × 1080 pixels) and transferred the video using a message passing interface. The total transfer time is around 53 ms or 19 fps. We will optimize and parallelize these algorithms to reduce the total time to 30 ms.

  9. Toward real-time remote processing of laparoscopic video

    PubMed Central

    Ronaghi, Zahra; Duffy, Edward B.; Kwartowitz, David M.

    2015-01-01

    Abstract. Laparoscopic surgery is a minimally invasive surgical technique where surgeons insert a small video camera into the patient’s body to visualize internal organs and use small tools to perform surgical procedures. However, the benefit of small incisions has a drawback of limited visualization of subsurface tissues, which can lead to navigational challenges in the delivering of therapy. Image-guided surgery uses the images to map subsurface structures and can reduce the limitations of laparoscopic surgery. One particular laparoscopic camera system of interest is the vision system of the daVinci-Si robotic surgical system (Intuitive Surgical, Sunnyvale, California). The video streams generate approximately 360 MB of data per second, demonstrating a trend toward increased data sizes in medicine, primarily due to higher-resolution video cameras and imaging equipment. Processing this data on a bedside PC has become challenging and a high-performance computing (HPC) environment may not always be available at the point of care. To process this data on remote HPC clusters at the typical 30 frames per second (fps) rate, it is required that each 11.9 MB video frame be processed by a server and returned within 1/30th of a second. The ability to acquire, process, and visualize data in real time is essential for the performance of complex tasks as well as minimizing risk to the patient. As a result, utilizing high-speed networks to access computing clusters will lead to real-time medical image processing and improve surgical experiences by providing real-time augmented laparoscopic data. We have performed image processing algorithms on a high-definition head phantom video (1920 × 1080 pixels) and transferred the video using a message passing interface. The total transfer time is around 53 ms or 19 fps. We will optimize and parallelize these algorithms to reduce the total time to 30 ms. PMID:26668817

  10. Towards real-time remote processing of laparoscopic video

    NASA Astrophysics Data System (ADS)

    Ronaghi, Zahra; Duffy, Edward B.; Kwartowitz, David M.

    2015-03-01

    Laparoscopic surgery is a minimally invasive surgical technique where surgeons insert a small video camera into the patient's body to visualize internal organs and small tools to perform surgical procedures. However, the benefit of small incisions has a drawback of limited visualization of subsurface tissues, which can lead to navigational challenges in the delivering of therapy. Image-guided surgery (IGS) uses images to map subsurface structures and can reduce the limitations of laparoscopic surgery. One particular laparoscopic camera system of interest is the vision system of the daVinci-Si robotic surgical system (Intuitive Surgical, Sunnyvale, CA, USA). The video streams generate approximately 360 megabytes of data per second, demonstrating a trend towards increased data sizes in medicine, primarily due to higher-resolution video cameras and imaging equipment. Processing this data on a bedside PC has become challenging and a high-performance computing (HPC) environment may not always be available at the point of care. To process this data on remote HPC clusters at the typical 30 frames per second (fps) rate, it is required that each 11.9 MB video frame be processed by a server and returned within 1/30th of a second. The ability to acquire, process and visualize data in real-time is essential for performance of complex tasks as well as minimizing risk to the patient. As a result, utilizing high-speed networks to access computing clusters will lead to real-time medical image processing and improve surgical experiences by providing real-time augmented laparoscopic data. We aim to develop a medical video processing system using an OpenFlow software defined network that is capable of connecting to multiple remote medical facilities and HPC servers.

  11. A real-time dashboard for managing pathology processes.

    PubMed

    Halwani, Fawaz; Li, Wei Chen; Banerjee, Diponkar; Lessard, Lysanne; Amyot, Daniel; Michalowski, Wojtek; Giffen, Randy

    2016-01-01

    The Eastern Ontario Regional Laboratory Association (EORLA) is a newly established association of all the laboratory and pathology departments of Eastern Ontario that currently includes facilities from eight hospitals. All surgical specimens for EORLA are processed in one central location, the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital (TOH), where the rapid growth and influx of surgical and cytology specimens has created many challenges in ensuring the timely processing of cases and reports. Although the entire process is maintained and tracked in a clinical information system, this system lacks pre-emptive warnings that can help management address issues as they arise. Dashboard technology provides automated, real-time visual clues that could be used to alert management when a case or specimen is not being processed within predefined time frames. We describe the development of a dashboard helping pathology clinical management to make informed decisions on specimen allocation and tracking. The dashboard was designed and developed in two phases, following a prototyping approach. The first prototype of the dashboard helped monitor and manage pathology processes at the DPLM. The use of this dashboard helped to uncover operational inefficiencies and contributed to an improvement of turn-around time within The Ottawa Hospital's DPML. It also allowed the discovery of additional requirements, leading to a second prototype that provides finer-grained, real-time information about individual cases and specimens. We successfully developed a dashboard that enables managers to address delays and bottlenecks in specimen allocation and tracking. This support ensures that pathology reports are provided within time frame standards required for high-quality patient care. Given the importance of rapid diagnostics for a number of diseases, the use of real-time dashboards within pathology departments could contribute to improving the quality of

  12. A real-time dashboard for managing pathology processes

    PubMed Central

    Halwani, Fawaz; Li, Wei Chen; Banerjee, Diponkar; Lessard, Lysanne; Amyot, Daniel; Michalowski, Wojtek; Giffen, Randy

    2016-01-01

    Context: The Eastern Ontario Regional Laboratory Association (EORLA) is a newly established association of all the laboratory and pathology departments of Eastern Ontario that currently includes facilities from eight hospitals. All surgical specimens for EORLA are processed in one central location, the Department of Pathology and Laboratory Medicine (DPLM) at The Ottawa Hospital (TOH), where the rapid growth and influx of surgical and cytology specimens has created many challenges in ensuring the timely processing of cases and reports. Although the entire process is maintained and tracked in a clinical information system, this system lacks pre-emptive warnings that can help management address issues as they arise. Aims: Dashboard technology provides automated, real-time visual clues that could be used to alert management when a case or specimen is not being processed within predefined time frames. We describe the development of a dashboard helping pathology clinical management to make informed decisions on specimen allocation and tracking. Methods: The dashboard was designed and developed in two phases, following a prototyping approach. The first prototype of the dashboard helped monitor and manage pathology processes at the DPLM. Results: The use of this dashboard helped to uncover operational inefficiencies and contributed to an improvement of turn-around time within The Ottawa Hospital's DPML. It also allowed the discovery of additional requirements, leading to a second prototype that provides finer-grained, real-time information about individual cases and specimens. Conclusion: We successfully developed a dashboard that enables managers to address delays and bottlenecks in specimen allocation and tracking. This support ensures that pathology reports are provided within time frame standards required for high-quality patient care. Given the importance of rapid diagnostics for a number of diseases, the use of real-time dashboards within pathology departments could

  13. GPU real-time processing in NA62 trigger system

    NASA Astrophysics Data System (ADS)

    Ammendola, R.; Biagioni, A.; Chiozzi, S.; Cretaro, P.; Di Lorenzo, S.; Fantechi, R.; Fiorini, M.; Frezza, O.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Martinelli, M.; Neri, I.; Paolucci, P. S.; Pastorelli, E.; Piandani, R.; Piccini, M.; Pontisso, L.; Rossetti, D.; Simula, F.; Sozzi, M.; Vicini, P.

    2017-01-01

    A commercial Graphics Processing Unit (GPU) is used to build a fast Level 0 (L0) trigger system tested parasitically with the TDAQ (Trigger and Data Acquisition systems) of the NA62 experiment at CERN. In particular, the parallel computing power of the GPU is exploited to perform real-time fitting in the Ring Imaging CHerenkov (RICH) detector. Direct GPU communication using a FPGA-based board has been used to reduce the data transmission latency. The performance of the system for multi-ring reconstrunction obtained during the NA62 physics run will be presented.

  14. HPC enabled real-time remote processing of laparoscopic surgery

    NASA Astrophysics Data System (ADS)

    Ronaghi, Zahra; Sapra, Karan; Izard, Ryan; Duffy, Edward; Smith, Melissa C.; Wang, Kuang-Ching; Kwartowitz, David M.

    2016-03-01

    Laparoscopic surgery is a minimally invasive surgical technique. The benefit of small incisions has a disadvantage of limited visualization of subsurface tissues. Image-guided surgery (IGS) uses pre-operative and intra-operative images to map subsurface structures. One particular laparoscopic system is the daVinci-si robotic surgical system. The video streams generate approximately 360 megabytes of data per second. Real-time processing this large stream of data on a bedside PC, single or dual node setup, has become challenging and a high-performance computing (HPC) environment may not always be available at the point of care. To process this data on remote HPC clusters at the typical 30 frames per second rate, it is required that each 11.9 MB video frame be processed by a server and returned within 1/30th of a second. We have implement and compared performance of compression, segmentation and registration algorithms on Clemson's Palmetto supercomputer using dual NVIDIA K40 GPUs per node. Our computing framework will also enable reliability using replication of computation. We will securely transfer the files to remote HPC clusters utilizing an OpenFlow-based network service, Steroid OpenFlow Service (SOS) that can increase performance of large data transfers over long-distance and high bandwidth networks. As a result, utilizing high-speed OpenFlow- based network to access computing clusters with GPUs will improve surgical procedures by providing real-time medical image processing and laparoscopic data.

  15. Real-time implementation of nonlinear optical processing functions

    NASA Astrophysics Data System (ADS)

    Soffer, B. H.; Owechko, Y.; Marom, E.

    1986-09-01

    For the past two decades optical data processing (ODP) has promised a vast increase in processing capacity and speed over conventional electronic techniques. This promise has never been fulfilled for several reasons, most notably because of the lack of a practical real-time image modulator, or light valve, and because optical techniques were almost exclusively limited to linear operations. These restrictions have been removed by the development of the liquid-crystal light valve (LCLV) by Hughes Research Laboratories (HRL), and by nonlinear parallel-processing techniques developed by the University of Southern California (USC). Thus, it is important to determine how successfully nonlinear parallel-processing techniques can be implemented in real time with the various LCLVs. In addition, other new optical technologies, highly developed at HRL, such as four-wave mixing and phase conjugation have inspired a novel research direction for this program in the field of optical associative memories and neural networks as models for computing. Here the phase conjugation provides the desired nonlinearities.

  16. A conceptual framework for intelligent real-time information processing

    NASA Technical Reports Server (NTRS)

    Schudy, Robert

    1987-01-01

    By combining artificial intelligence concepts with the human information processing model of Rasmussen, a conceptual framework was developed for real time artificial intelligence systems which provides a foundation for system organization, control and validation. The approach is based on the description of system processing terms of an abstraction hierarchy of states of knowledge. The states of knowledge are organized along one dimension which corresponds to the extent to which the concepts are expressed in terms of the system inouts or in terms of the system response. Thus organized, the useful states form a generally triangular shape with the sensors and effectors forming the lower two vertices and the full evaluated set of courses of action the apex. Within the triangle boundaries are numerous processing paths which shortcut the detailed processing, by connecting incomplete levels of analysis to partially defined responses. Shortcuts at different levels of abstraction include reflexes, sensory motor control, rule based behavior, and satisficing. This approach was used in the design of a real time tactical decision aiding system, and in defining an intelligent aiding system for transport pilots.

  17. Closed-Loop Endoatmospheric Ascent Guidance

    NASA Technical Reports Server (NTRS)

    Lu, Ping; Sun, Hongsheng; Jackson, Scott (Technical Monitor)

    2002-01-01

    This paper will present a complete formulation of the optimal control problem for atmospheric ascent of rocket powered launch vehicles subject to usual load constraints and final condition constraints. We shall demonstrate that the classical finite difference method for two-point-boundary-value-problems (TPBVP) is suited for solving the ascent trajectory optimization problem in real time, therefore closed-loop optimal endoatmospheric ascent guidance becomes feasible. Numerical simulations with a the vehicle data of a reusable launch vehicle will be provided.

  18. Real-time processing for the ATST AO system

    NASA Astrophysics Data System (ADS)

    Richards, K.; Rimmele, T.

    The real-time processing requirements for the four meter Advanced Technology Solar Telescope extended source high order adaptive optics system will be approximately 15 times that of the Dunn Solar Telescope AO systems on which the ATST AO system is based. The ATST AO, with its approximately 1232 subapertures, will use massively parallel processing and is based on Analog Devices TigerSHARC DSPs as the central processing units. We will discuss the requirements for processing and data handling and the architecture of the correlating Shack-Hartmannn and reconstructor processing unit and present the results of bench-mark testing of the DSP hardware that was selected for the ATST AO system.

  19. Near Real-Time Processing of Proteomics Data Using Hadoop.

    PubMed

    Hillman, Chris; Ahmad, Yasmeen; Whitehorn, Mark; Cobley, Andy

    2014-03-01

    This article presents a near real-time processing solution using MapReduce and Hadoop. The solution is aimed at some of the data management and processing challenges facing the life sciences community. Research into genes and their product proteins generates huge volumes of data that must be extensively preprocessed before any biological insight can be gained. In order to carry out this processing in a timely manner, we have investigated the use of techniques from the big data field. These are applied specifically to process data resulting from mass spectrometers in the course of proteomic experiments. Here we present methods of handling the raw data in Hadoop, and then we investigate a process for preprocessing the data using Java code and the MapReduce framework to identify 2D and 3D peaks.

  20. Real-Time Monitoring of Psychotherapeutic Processes: Concept and Compliance

    PubMed Central

    Schiepek, Günter; Aichhorn, Wolfgang; Gruber, Martin; Strunk, Guido; Bachler, Egon; Aas, Benjamin

    2016-01-01

    Objective: The feasibility of a high-frequency real-time monitoring approach to psychotherapy is outlined and tested for patients' compliance to evaluate its integration to everyday practice. Criteria concern the ecological momentary assessment, the assessment of therapy-related cognitions and emotions, equidistant time sampling, real-time nonlinear time series analysis, continuous participative process control by client and therapist, and the application of idiographic (person-specific) surveys. Methods: The process-outcome monitoring is technically realized by an internet-based device for data collection and data analysis, the Synergetic Navigation System. Its feasibility is documented by a compliance study on 151 clients treated in an inpatient and a day-treatment clinic. Results: We found high compliance rates (mean: 78.3%, median: 89.4%) amongst the respondents, independent of the severity of symptoms or the degree of impairment. Compared to other diagnoses, the compliance rate was lower in the group diagnosed with personality disorders. Conclusion: The results support the feasibility of high-frequency monitoring in routine psychotherapy settings. Daily collection of psychological surveys allows for the assessment of highly resolved, equidistant time series data which gives insight into the nonlinear qualities of therapeutic change processes (e.g., pattern transitions, critical instabilities). PMID:27199837

  1. Real-Time Process Analytics in Emergency Healthcare.

    PubMed

    Koufi, Vassiliki; Malamateniou, Flora; Prentza, Adrianna; Vassilacopoulos, George

    2017-01-01

    Emergency medical systems (EMS) are considered to be amongst the most crucial systems as they involve a variety of activities which are performed from the time of a call to an ambulance service till the time of patient's discharge from the emergency department of a hospital. These activities are closely interrelated so that collaboration and coordination becomes a vital issue for patients and for emergency healthcare service performance. The utilization of standard workflow technology in the context of Service Oriented Architecture can provide an appropriate technological infrastructure for defining and automating EMS processes that span organizational boundaries so that to create and empower collaboration and coordination among the participating organizations. In such systems, the utilization of leading-edge analytics tools can prove important as it can facilitate real-time extraction and visualization of useful insights from the mountains of generated data pertaining to emergency case management. This paper presents a framework which provides healthcare professionals with just-in-time insight within and across emergency healthcare processes by performing real-time analysis on process-related data in order to better support decision making and identify potential critical risks that may affect the provision of emergency care to patients.

  2. Cellular Neural Network for Real Time Image Processing

    SciTech Connect

    Vagliasindi, G.; Arena, P.; Fortuna, L.; Mazzitelli, G.; Murari, A.

    2008-03-12

    Since their introduction in 1988, Cellular Nonlinear Networks (CNNs) have found a key role as image processing instruments. Thanks to their structure they are able of processing individual pixels in a parallel way providing fast image processing capabilities that has been applied to a wide range of field among which nuclear fusion. In the last years, indeed, visible and infrared video cameras have become more and more important in tokamak fusion experiments for the twofold aim of understanding the physics and monitoring the safety of the operation. Examining the output of these cameras in real-time can provide significant information for plasma control and safety of the machines. The potentiality of CNNs can be exploited to this aim. To demonstrate the feasibility of the approach, CNN image processing has been applied to several tasks both at the Frascati Tokamak Upgrade (FTU) and the Joint European Torus (JET)

  3. Cellular Neural Network for Real Time Image Processing

    NASA Astrophysics Data System (ADS)

    Vagliasindi, G.; Arena, P.; Fortuna, L.; Mazzitelli, G.; Murari, A.

    2008-03-01

    Since their introduction in 1988, Cellular Nonlinear Networks (CNNs) have found a key role as image processing instruments. Thanks to their structure they are able of processing individual pixels in a parallel way providing fast image processing capabilities that has been applied to a wide range of field among which nuclear fusion. In the last years, indeed, visible and infrared video cameras have become more and more important in tokamak fusion experiments for the twofold aim of understanding the physics and monitoring the safety of the operation. Examining the output of these cameras in real-time can provide significant information for plasma control and safety of the machines. The potentiality of CNNs can be exploited to this aim. To demonstrate the feasibility of the approach, CNN image processing has been applied to several tasks both at the Frascati Tokamak Upgrade (FTU) and the Joint European Torus (JET).

  4. A novel parallel architecture for real-time image processing

    NASA Astrophysics Data System (ADS)

    Hu, Junhong; Zhang, Tianxu; Zhong, Sheng; Chen, Xujun

    2009-10-01

    A novel DSP/FPGA-based parallel architecture for real-time image processing is presented in this paper, DSPs are the main processing unit and FPGAs are used to be logic units for image interface protocol, image processing, image display, synchronization communication portocol of DSPs and DSP's reprogramming interface of 422/485. The presented architecture is composed of two modules: the preprocessing module and the processing module, and the latter is extendable for better performance. Modules are connected by LINK communication port, whose LVDS protocol has the ability of anti-jamming. And DSP's programs can be updated easily by 422/485 with PC's serial port. Analysis and experiments result shows that the prototype with the proposed parallel architecture has many promising charactersitics such as powerful computing capability, broad data transfer bandwidth, and is easy to be extended and updated.

  5. Development of real-time extensometer based on image processing

    NASA Astrophysics Data System (ADS)

    Adinanta, H.; Puranto, P.; Suryadi

    2017-04-01

    An extensometer system was developed by using high definition web camera as main sensor to track object position. The developed system applied digital image processing techniques. The image processing was used to measure the change of object position. The position measurement was done in real-time so that the system can directly showed the actual position in both x and y-axis. In this research, the relation between pixel and object position changes had been characterized. The system was tested by moving the target in a range of 20 cm in interval of 1 mm. To verify the long run performance, the stability and linearity of continuous measurements on both x and y-axis, this measurement had been conducted for 83 hours. The results show that this image processing-based extensometer had both good stability and linearity.

  6. Real-time interferometric monitoring and measuring of photopolymerization based stereolithographic additive manufacturing process: sensor model and algorithm

    NASA Astrophysics Data System (ADS)

    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.

  7. A real-time optical data processing device

    NASA Technical Reports Server (NTRS)

    Jacobson, A.; Grinberg, J.; Bleha, W.; Miller, L.; Fraas, L.; Myer, G.; Boswell, D.

    1976-01-01

    A novel liquid-crystal electro-optical device useful as a real-time input device in coherent optical data processing is described. The device is a special adaptation of an ac photoactivated liquid-crystal light valve, and utilizes a hybrid field effect (45 deg twisted nematic effect in OFF state and pure optical birefringence of the liquid crystal in ON state). A thin-film sandwich exerts photoelectric control over the optical birefringence of a thin liquid-crystal layer. Liquid-crystal layer thickness is successfully reduced without image degradation. The device offers high resolution (better than 100 lines/mm), contrast (better than 100/1), high speed (10 msec ON, 15 msec OFF), high input sensitivity, low power input, low fabrication cost, and can be operated at below 10 V rms. Preliminary measurements on device performance in level slicing, filtering, contrast reversal, and edge enhancement are under way.

  8. Online Anomaly Prediction for Real-Time Stream Processing

    NASA Astrophysics Data System (ADS)

    Huang, Yuanqiang; Luan, Zhongzhi; Qian, Depei; Du, Zhigao; Chen, Ting; Bai, Yuebin

    With the consideration of real-time stream processing technology, it's important to develop high availability mechanism to guarantee stream-based application not interfered by faults caused by potential anomalies. In this paper, we present a novel online prediction technique for predicting some anomalies which may occur in the near future. Concretely, we first present a value prediction which combines the Hidden Markov Model and the Mixture of Expert Model to predict the values of feature metrics in the near future. Then we employ the Support Vector Machine to do anomaly identification, which is a procedure to identify the kind of anomaly that we are about to alarm. The purpose of our approach is to achieve a tradeoff between fault penalty and resource cost. The experiment results show that our approach is of high accuracy for common anomaly prediction and low runtime overhead.

  9. Real time study of development process in holographic emulsions

    NASA Astrophysics Data System (ADS)

    Fimia, A.; Blaya, S.; Carretero, L.; Madrigal, R. F.; Mallavia, R.

    2000-01-01

    In this paper we present the theoretical and experimental study using a real time technique for the measurement of the optical density when the emulsion is developing. Good agreement was observed between theory and experiment. We exposed an Agfa Gevaert 8E56HD emulsion with an Argon laser tuned at 514 nm and we measured the variation in optical density when the emulsion was put into the developer bath at 20°C. This method allows us to study the dynamics of different developers at different energy of storage. It also provides a way to optimize the composition of developers as a function of the chemical composition, temperature and other secondary factors as superadditivity and non-linear processes.

  10. The psychophysiology of real-time financial risk processing.

    PubMed

    Lo, Andrew W; Repin, Dmitry V

    2002-04-01

    A longstanding controversy in economics and finance is whether financial markets are governed by rational forces or by emotional responses. We study the importance of emotion in the decision-making process of professional securities traders by measuring their physiological characteristics (e.g., skin conductance, blood volume pulse, etc.) during live trading sessions while simultaneously capturing real-time prices from which market events can be detected. In a sample of 10 traders, we find statistically significant differences in mean electrodermal responses during transient market events relative to no-event control periods, and statistically significant mean changes in cardiovascular variables during periods of heightened market volatility relative to normal-volatility control periods. We also observe significant differences in these physiological responses across the 10 traders that may be systematically related to the traders' levels of experience.

  11. Real-time depth processing for embedded platforms

    NASA Astrophysics Data System (ADS)

    Rahnama, Oscar; Makarov, Aleksej; Torr, Philip

    2017-05-01

    Obtaining depth information of a scene is an important requirement in many computer-vision and robotics applications. For embedded platforms, passive stereo systems have many advantages over their active counterparts (i.e. LiDAR, Infrared). They are power efficient, cheap, robust to lighting conditions and inherently synchronized to the RGB images of the scene. However, stereo depth estimation is a computationally expensive task that operates over large amounts of data. For embedded applications which are often constrained by power consumption, obtaining accurate results in real-time is a challenge. We demonstrate a computationally and memory efficient implementation of a stereo block-matching algorithm in FPGA. The computational core achieves a throughput of 577 fps at standard VGA resolution whilst consuming less than 3 Watts of power. The data is processed using an in-stream approach that minimizes memory-access bottlenecks and best matches the raster scan readout of modern digital image sensors.

  12. Near Real Time Processing Chain for Suomi NPP Satellite Data

    NASA Astrophysics Data System (ADS)

    Monsorno, Roberto; Cuozzo, Giovanni; Costa, Armin; Mateescu, Gabriel; Ventura, Bartolomeo; Zebisch, Marc

    2014-05-01

    Since 2009, the EURAC satellite receiving station, located at Corno del Renon, in a free obstacle site at 2260 m a.s.l., has been acquiring data from Aqua and Terra NASA satellites equipped with Moderate Resolution Imaging Spectroradiometer (MODIS) sensors. The experience gained with this local ground segmenthas given the opportunity of adapting and modifying the processing chain for MODIS data to the Suomi NPP, the natural successor to Terra and Aqua satellites. The processing chain, initially implemented by mean of a proprietary system supplied by Seaspace and Advanced Computer System, was further developed by EURAC's Institute for Applied Remote Sensing engineers. Several algorithms have been developed using MODIS and Visible Infrared Imaging Radiometer Suite (VIIRS) data to produce Snow Cover, Particulate Matter estimation and Meteo maps. These products are implemented on a common processor structure based on the use of configuration files and a generic processor. Data and products have then automatically delivered to the customers such as the Autonomous Province of Bolzano-Civil Protection office. For the processing phase we defined two goals: i) the adaptation and implementation of the products already available for MODIS (and possibly new ones) to VIIRS, that is one of the sensors onboard Suomi NPP; ii) the use of an open source processing chain in order to process NPP data in Near Real Time, exploiting the knowledge we acquired on parallel computing. In order to achieve the second goal, the S-NPP data received and ingested are sent as input to RT-STPS (Real-time Software Telemetry Processing System) software developed by the NASA Direct Readout Laboratory 1 (DRL) that gives as output RDR files (Raw Data Record) for VIIRS, ATMS (Advanced Technology Micorwave Sounder) and CrIS (Cross-track Infrared Sounder)sensors. RDR are then transferred to a server equipped with CSPP2 (Community Satellite Processing Package) software developed by the University of

  13. A digital wireless system for closed-loop inhibition of nociceptive signals

    NASA Astrophysics Data System (ADS)

    Zuo, Chao; Yang, Xiaofei; Wang, Yang; Hagains, Christopher E.; Li, Ai-Ling; Peng, Yuan B.; Chiao, J.-C.

    2012-10-01

    Neurostimulation of the spinal cord or brain has been used to inhibit nociceptive signals in pain management applications. Nevertheless, most of the current neurostimulation models are based on open-loop system designs. There is a lack of closed-loop systems for neurostimulation in research with small freely-moving animals and in future clinical applications. Based on our previously developed analog wireless system for closed-loop neurostimulation, a digital wireless system with real-time feedback between recorder and stimulator modules has been developed to achieve multi-channel communication. The wireless system includes a wearable recording module, a wearable stimulation module and a transceiver connected to a computer for real-time and off-line data processing, display and storage. To validate our system, wide dynamic range neurons in the spinal cord dorsal horn have been recorded from anesthetized rats in response to graded mechanical stimuli (brush, pressure and pinch) applied in the hind paw. The identified nociceptive signals were used to automatically trigger electrical stimulation at the periaqueductal gray in real time to inhibit their own activities by the closed-loop design. Our digital wireless closed-loop system has provided a simplified and efficient method for further study of pain processing in freely-moving animals and potential clinical application in patients. Groups 1, 2 and 3 contributed equally to this project.

  14. A digital wireless system for closed-loop inhibition of nociceptive signals.

    PubMed

    Zuo, Chao; Yang, Xiaofei; Wang, Yang; Hagains, Christopher E; Li, Ai-Ling; Peng, Yuan B; Chiao, J-C

    2012-10-01

    Neurostimulation of the spinal cord or brain has been used to inhibit nociceptive signals in pain management applications. Nevertheless, most of the current neurostimulation models are based on open-loop system designs. There is a lack of closed-loop systems for neurostimulation in research with small freely-moving animals and in future clinical applications. Based on our previously developed analog wireless system for closed-loop neurostimulation, a digital wireless system with real-time feedback between recorder and stimulator modules has been developed to achieve multi-channel communication. The wireless system includes a wearable recording module, a wearable stimulation module and a transceiver connected to a computer for real-time and off-line data processing, display and storage. To validate our system, wide dynamic range neurons in the spinal cord dorsal horn have been recorded from anesthetized rats in response to graded mechanical stimuli (brush, pressure and pinch) applied in the hind paw. The identified nociceptive signals were used to automatically trigger electrical stimulation at the periaqueductal gray in real time to inhibit their own activities by the closed-loop design. Our digital wireless closed-loop system has provided a simplified and efficient method for further study of pain processing in freely-moving animals and potential clinical application in patients.

  15. Generating microbial survival curves during thermal processing in real time.

    PubMed

    Peleg, M; Normand, M D; Corradini, M G

    2005-01-01

    To develop a method to calculate and record theoretical microbial survival curves during thermal processing of foods and pharmaceutical products simultaneously with the changing temperature. Moreover, to demonstrate that the method can be used to calculate nonisothermal survival curves, with widely available software such as Microsoft Excel. It has been assumed that the targeted organism's isothermal survival curves are not log linear and hence, the inactivation rate in nonisothermal processes is a function of the momentary temperature and the corresponding survival ratio. This could be expressed by a difference equation, which is an approximation to the continuous rate model. The concept was tested with the isothermal survival parameters of Clostridium botulinum and Bacillus sporothermodurans spores, and Salmonella enteritidis cells, using different kinds of survival models and under temperature profiles resembling those of commercial processes. As expected, there was an excellent agreement between the curves produced by solving the differential equation of the continuous model and by the incremental method, which has been posted on the web as freeware. It is possible to calculate nonisothermal survival curves, in real time, with an algorithm that can be written in the language of general purpose software, to follow the inactivation of one or more targeted organisms simultaneously and to simulate microbial survival patterns under existing or planned industrial thermal processes. Replacement of the traditional 'F0-value', which requires the log linearity of the organism's isothermal survival curves, by the more realistic theoretical survival ratio estimate as a measure of the thermal process efficacy.

  16. Acoustic sensor for real-time control for the inductive heating process

    DOEpatents

    Kelley, John Bruce; Lu, Wei-Yang; Zutavern, Fred J.

    2003-09-30

    Disclosed is a system and method for providing closed-loop control of the heating of a workpiece by an induction heating machine, including generating an acoustic wave in the workpiece with a pulsed laser; optically measuring displacements of the surface of the workpiece in response to the acoustic wave; calculating a sub-surface material property by analyzing the measured surface displacements; creating an error signal by comparing an attribute of the calculated sub-surface material properties with a desired attribute; and reducing the error signal below an acceptable limit by adjusting, in real-time, as often as necessary, the operation of the inductive heating machine.

  17. Cell-bionics: tools for real-time sensor processing.

    PubMed

    Toumazou, Chris; Cass, Tony

    2007-08-29

    The accurate monitoring of the physiological status of cells, tissues and whole organisms demands a new generation of devices capable of providing accurate data in real time with minimal perturbation of the system being measured. To deliver on the promise of cell-bionics advances over the past decade in miniaturization, analogue signal processing, low-power electronics, materials science and protein engineering need to be brought together. In this paper we summarize recent advances in our research that is moving us in this direction. Two areas in particular are highlighted: the exploitation of the physical properties inherent in semiconductor devices to perform very low power on chip signal processing and the use of gene technology to tailor proteins for sensor applications. In the context of engineered tissues, cell-bionics could offer the ability to monitor the precise physiological state of the construct, both during 'manufacture' and post-implantation. Monitoring during manufacture, particularly by embedded devices, would offer quality assurance of the materials components and the fabrication process. Post-implantation monitoring would reveal changes in the underlying physiology as a result of the tissue construct adapting to its new environment.

  18. Real-Time Signal Processing Data Acquisition Subsystem

    NASA Astrophysics Data System (ADS)

    Sarafinas, George A.; Stein, Alan J.; Bisson, Kenneth J.

    A digital signal processing sub-system has been developed for a coherent carbon dioxide laser radar system at Lincoln Laboratory's Firepond Research Facility. This high-resolution radar is capable of operating with a variety of waveforms; hence, the signal processing requirements of the sub-system vary from one application to the next, and require a sub-system with a high degree of flexibility. The primary function of the Data Acquisition sub-system is to provide range-Doppler images in real-time. Based on this objective, the sub-system must have the ability to route large amounts of digitized data at high rates between specialized processors performing the functions of data acquisition, digital signal processing, archiving, and image processing. A distributed processing design approach was used and the hardware design implemented was configured using all off-the-shelf commercially available products. The sub-system uses a high speed 24 MB/sec central bus and associated processor acting as the hub of the system. Attached to the bus is a large RAM memory buffer. Also attached to the central bus are individual processors which interface to specialized peripherals, performing the tasks of digitizing, vector processing, imaging, and archiving. The software for the complete Data Acquisition and Signal Processing sub-system was developed on a Digital Equipment MicroVAX IITM computer. Software developed for the completed system is coded mostly in a high level language to promote flexibility, modularity, and reducing development time. Some microcode had to be used where speed is essential. All Software design, development, and testing was done under VMSTM.

  19. Closed loop steam cooled airfoil

    DOEpatents

    Widrig, Scott M.; Rudolph, Ronald J.; Wagner, Gregg P.

    2006-04-18

    An airfoil, a method of manufacturing an airfoil, and a system for cooling an airfoil is provided. The cooling system can be used with an airfoil located in the first stages of a combustion turbine within a combined cycle power generation plant and involves flowing closed loop steam through a pin array set within an airfoil. The airfoil can comprise a cavity having a cooling chamber bounded by an interior wall and an exterior wall so that steam can enter the cavity, pass through the pin array, and then return to the cavity to thereby cool the airfoil. The method of manufacturing an airfoil can include a type of lost wax investment casting process in which a pin array is cast into an airfoil to form a cooling chamber.

  20. Assisted closed-loop optimization of SSVEP-BCI efficiency

    PubMed Central

    Fernandez-Vargas, Jacobo; Pfaff, Hanns U.; Rodríguez, Francisco B.; Varona, Pablo

    2012-01-01

    We designed a novel assisted closed-loop optimization protocol to improve the efficiency of brain-computer interfaces (BCI) based on steady state visually evoked potentials (SSVEP). In traditional paradigms, the control over the BCI-performance completely depends on the subjects' ability to learn from the given feedback cues. By contrast, in the proposed protocol both the subject and the machine share information and control over the BCI goal. Generally, the innovative assistance consists in the delivery of online information together with the online adaptation of BCI stimuli properties. In our case, this adaptive optimization process is realized by (1) a closed-loop search for the best set of SSVEP flicker frequencies and (2) feedback of actual SSVEP magnitudes to both the subject and the machine. These closed-loop interactions between subject and machine are evaluated in real-time by continuous measurement of their efficiencies, which are used as online criteria to adapt the BCI control parameters. The proposed protocol aims to compensate for variability in possibly unknown subjects' state and trait dimensions. In a study with N = 18 subjects, we found significant evidence that our protocol outperformed classic SSVEP-BCI control paradigms. Evidence is presented that it takes indeed into account interindividual variabilities: e.g., under the new protocol, baseline resting state EEG measures predict subjects' BCI performances. This paper illustrates the promising potential of assisted closed-loop protocols in BCI systems. Probably their applicability might be expanded to innovative uses, e.g., as possible new diagnostic/therapeutic tools for clinical contexts and as new paradigms for basic research. PMID:23443214

  1. GPUs for real-time processing in HEP trigger systems

    NASA Astrophysics Data System (ADS)

    Lamanna, G.; Ammendola, R.; Bauce, M.; Biagioni, A.; Fantechi, R.; Fiorini, M.; Giagu, S.; Graverini, E.; Lamanna, G.; Lonardo, A.; Messina, A.; Pantaleo, F.; Paolucci, P. S.; Piandani, R.; Rescigno, M.; Simula, F.; Sozzi, M.; Vicini, P.

    2014-06-01

    We describe a pilot project for the use of Graphics Processing Units (GPUs) for online triggering applications in High Energy Physics (HEP) experiments. Two major trends can be identified in the development of trigger and DAQ systems for HEP experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a pure software selection system (trigger-less). The very innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software both at low- and high-level trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerator in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high-energy physics data acquisition and trigger systems is becoming very attractive. We discuss in details the use of online parallel computing on GPUs for synchronous low-level trigger with fixed latency. In particular we show preliminary results on a first test in the NA62 experiment at CERN. The use of GPUs in high-level triggers is also considered, the ATLAS experiment (and in particular the muon trigger) at CERN will be taken as a study case of possible applications.

  2. GPUs for real-time processing in HEP trigger systems

    NASA Astrophysics Data System (ADS)

    Ammendola, R.; Biagioni, A.; Deri, L.; Fiorini, M.; Frezza, O.; Lamanna, G.; Lo Cicero, F.; Lonardo, A.; Messina, A.; Sozzi, M.; Pantaleo, F.; Paolucci, Ps; Rossetti, D.; Simula, F.; Tosoratto, L.; Vicini, P.; Gap Collaboration

    2014-06-01

    We describe a pilot project (GAP - GPU Application Project) for the use of GPUs (Graphics processing units) for online triggering applications in High Energy Physics experiments. Two major trends can be identified in the development of trigger and DAQ systems for particle physics experiments: the massive use of general-purpose commodity systems such as commercial multicore PC farms for data acquisition, and the reduction of trigger levels implemented in hardware, towards a fully software data selection system ("trigger-less"). The innovative approach presented here aims at exploiting the parallel computing power of commercial GPUs to perform fast computations in software not only in high level trigger levels but also in early trigger stages. General-purpose computing on GPUs is emerging as a new paradigm in several fields of science, although so far applications have been tailored to the specific strengths of such devices as accelerators in offline computation. With the steady reduction of GPU latencies, and the increase in link and memory throughputs, the use of such devices for real-time applications in high energy physics data acquisition and trigger systems is becoming relevant. We discuss in detail the use of online parallel computing on GPUs for synchronous low-level triggers with fixed latency. In particular we show preliminary results on a first test in the CERN NA62 experiment. The use of GPUs in high level triggers is also considered, the CERN ATLAS experiment being taken as a case study of possible applications.

  3. Hybrid integrated optic modules for real-time signal processing

    NASA Technical Reports Server (NTRS)

    Tsai, C. S.

    1984-01-01

    The most recent progress on four relatively new hybrid integrated optic device modules in LiNbO3 waveguides and one in YIG/GGG waveguide that are currently being studied are discussed. The five hybrid modules include a time-integrating acoustooptic correlator, a channel waveguide acoustooptic frequency shifter/modulator, an electrooptic channel waveguide total internal reflection moculator/switch, an electrooptic analog-to-digital converter using a Fabry-Perot modulator array, and a noncollinear magnetooptic modulator using magnetostatic surface waves. All of these devices possess the desirable characteristics of very large bandwidth (GHz or higher), very small substrate size along the optical path (typically 1.5 cm or less), single-mode optical propagation, and low drive power requirement. The devices utilize either acoustooptic, electrooptic or magnetooptic effects in planar or channel waveguides and, therefore, act as efficient interface devices between a light wave and temporal signals. Major areas of application lie in wideband multichannel optical real-time signal processing and communications. Some of the specific applications include spectral analysis and correlation of radio frequency (RF) signals, fiber-optic sensing, optical computing and multiport switching/routing, and analog-to-digital conversion of wide RF signals.

  4. Hybrid integrated optic modules for real-time signal processing

    NASA Astrophysics Data System (ADS)

    Tsai, C. S.

    1984-03-01

    The most recent progress on four relatively new hybrid integrated optic device modules in LiNbO3 waveguides and one in YIG/GGG waveguide that are currently being studied are discussed. The five hybrid modules include a time-integrating acoustooptic correlator, a channel waveguide acoustooptic frequency shifter/modulator, an electrooptic channel waveguide total internal reflection moculator/switch, an electrooptic analog-to-digital converter using a Fabry-Perot modulator array, and a noncollinear magnetooptic modulator using magnetostatic surface waves. All of these devices possess the desirable characteristics of very large bandwidth (GHz or higher), very small substrate size along the optical path (typically 1.5 cm or less), single-mode optical propagation, and low drive power requirement. The devices utilize either acoustooptic, electrooptic or magnetooptic effects in planar or channel waveguides and, therefore, act as efficient interface devices between a light wave and temporal signals. Major areas of application lie in wideband multichannel optical real-time signal processing and communications. Some of the specific applications include spectral analysis and correlation of radio frequency (RF) signals, fiber-optic sensing, optical computing and multiport switching/routing, and analog-to-digital conversion of wide RF signals.

  5. Hybrid integrated optic modules for real-time signal processing

    NASA Technical Reports Server (NTRS)

    Tsai, C. S.

    1984-01-01

    The most recent progress on four relatively new hybrid integrated optic device modules in LiNbO3 waveguides and one in YIG/GGG waveguide that are currently being studied are discussed. The five hybrid modules include a time-integrating acoustooptic correlator, a channel waveguide acoustooptic frequency shifter/modulator, an electrooptic channel waveguide total internal reflection moculator/switch, an electrooptic analog-to-digital converter using a Fabry-Perot modulator array, and a noncollinear magnetooptic modulator using magnetostatic surface waves. All of these devices possess the desirable characteristics of very large bandwidth (GHz or higher), very small substrate size along the optical path (typically 1.5 cm or less), single-mode optical propagation, and low drive power requirement. The devices utilize either acoustooptic, electrooptic or magnetooptic effects in planar or channel waveguides and, therefore, act as efficient interface devices between a light wave and temporal signals. Major areas of application lie in wideband multichannel optical real-time signal processing and communications. Some of the specific applications include spectral analysis and correlation of radio frequency (RF) signals, fiber-optic sensing, optical computing and multiport switching/routing, and analog-to-digital conversion of wide RF signals.

  6. The Real-Time Processing of Sluiced Sentences

    PubMed Central

    Wolfinger, Katie; Spellman, Lisa; Shapiro, Lewis P.

    2012-01-01

    Ellipsis refers to an element that is absent from the input but whose meaning can nonetheless be recovered from context. In this cross-modal priming study, we examined the online processing of Sluicing, an ellipsis whose antecedent is an entire clause: The handyman threw a book to the programmer but I don’t know which book the handyman threw to the programmerellipsis. To understand such an elliptical construction, the listener arguably must ‘fill in’ the missing material (“the handyman threw___ to the programmer”) based on that which occurs in the antecedent clause. We aimed to determine the point in time in which reconstruction of the sluiced sentence is attempted and whether such a complex antecedent is re-accessed by the ellipsis. Out of the two antecedent constituents for which we probed, only the Object (programmer) was found active in the elliptical clause, confirming that an antecedent is attributed to the sluice in real time. Possible reasons for the non-observation of the Subject (handyman) are considered. We also suggest that ellipses are detected earlier in coordinated than subordinated sentences. PMID:20229060

  7. Kalman filtering for real-time navigator processing.

    PubMed

    Spincemaille, Pascal; Nguyen, Thanh D; Prince, Martin R; Wang, Yi

    2008-07-01

    Navigator echoes are used in high-resolution cardiac MRI for tracking physiological motion to suppress motion artifacts. Alternatives to the conventional diaphragm navigator such as the cardiac fat navigator and the k-space center signal (self-navigator) were developed to monitor heart motion directly. These navigator data can be noisy or may contain undesirable frequency components. Real-time filtering of navigator data without delay, as opposed to the previously used retrospective frequency band filtering, is required for effective prospective navigator gating. One of the commonly used real-time filtering techniques is the Kalman filter, which adaptively estimates motion and suppresses measurement noise by using Bayesian statistics and a motion model. The Kalman filter is investigated in this work to filter noise and distinguish cardiac and respiratory components in navigator data. Preliminary imaging data demonstrate the feasibility of real-time Kalman filtering for prospective respiratory self-gating in CINE cardiac MRI.

  8. Closed loop spray cooling apparatus

    NASA Technical Reports Server (NTRS)

    Alger, D. L.; Schwab, W. B.; Furman, E. R. (Inventor)

    1979-01-01

    A closed loop apparatus for jet spraying coolant against the back of a radiation target is described. The coolant is circulated through a closed loop with a bubble of inert gas being maintained around the spray. Mesh material is disposed between the bubble and the surface of the liquid coolant which is below the bubble at a predetermined level. In a second arrangement no inert gas is used, the bubble consists of vapor produced when the coolant is sprayed against the target.

  9. Virtual proprioception with real-time step detection and processing.

    PubMed

    Lemoyne, Robert; Coroian, Cristian; Mastroianni, Timothy; Wu, Winston; Grundfest, Warren; Kaiser, William

    2008-01-01

    Virtual proprioception is a novel device for providing near autonomous biofeedback of hemiparetic gait disparity in real time. With virtual proprioception a user may modify gait dynamics to develop a more suitable gait in tandem with real time feedback. Accelerometers are fundamental to the operation of the device, and a thorough consideration of the accelerometry technology space for locomotion quantification is included. The role of traumatic brain injury and respective decrements to gait quality and proprioceptive feedback are addressed. Virtual proprioception conceptual test and evaluation yielded positive results. The active 'on' status of the virtual proprioception biofeedback for alternative gait strategy was bounded by a 90% confidence level with a 10% margin of error.

  10. An approach to real-time simulation using parallel processing

    NASA Technical Reports Server (NTRS)

    Blech, R. A.; Arpasi, D. J.

    1981-01-01

    Current applications of real-time simulations to the development of complex aircraft propulsion system controls have demonstrated the need for accurate, portable, and low-cost simulators. This paper presents a preliminary simulator design that uses a parallel computer organization to provide these features. The hardware and software for this prototype simulator are discussed. A detailed discussion of the inter-computer data transfer mechanism is also presented.

  11. Real-Time Implementation of Nonlinear Optical Processing Functions.

    DTIC Science & Technology

    1986-09-30

    demonstrating that the memory is nonlinear and selective. The recording medium could be replaced with real-time media such as photorefractive crystals. Thicker...recording media Fi4 4. Schematic of experiment that d,.non* trated ,,pera have the added advantage of higher angular selectiv- "" . e e r aity. thus... geometrica snapes in contact ’A,.n a c-:’:ser ’Figure 51a’ ., and a spher:cal 4:verg.ng reference -eam Upion :"um’latlon of t -" c-’gram by the object beam

  12. Adaptive real-time signal processing for image enhancement

    NASA Astrophysics Data System (ADS)

    Sadjadi, Firooz A.; Au, Wing K.

    1993-09-01

    A significant need exists for autonomous landing of an aircraft in adverse weather conditions, e.g., fog, haze, rain or snow. Such systems must provide the pilot the ability to view the runway and its surrounding with timely display information for each weather landing category. The most important requirements of such vision systems include a large field-of-view, a high update/frame rate, and high spatial resolution at low glazing angle in poor visibility conditions. To satisfy these requirements, Honeywell's System and Research Center has developed and demonstrated through flight tests the feasibility of a synthetic vision system for aircraft landing. This paper introduces the concept of the synthetic vision system, based on the Honeywell 35 GHz millimeter wave radar. It provides a detailed discussion on the adaptive image enhancement algorithms and their real-time implementation. The algorithms include beam sharpening and range adaptive contrast enhancement.

  13. Closed-Loop Rehabilitation of Age-Related Cognitive Disorders

    PubMed Central

    Mishra, Jyoti; Gazzaley, Adam

    2015-01-01

    Cognitive deficits are common in older adults, as a result of both the natural aging process and neurodegenerative disease. Although medical advancements have successfully prolonged the human lifespan, the challenge of remediating cognitive aging remains. The authors discuss the current state of cognitive therapeutic interventions and then present the need for development and validation of more powerful neurocognitive therapeutics. They propose that the next generation of interventions be implemented as closed-loop systems that target specific neural processing deficits, incorporate quantitative feedback to the individual and clinician, and are personalized to the individual’s neurocognitive capacities using real-time performance-adaptive algorithms. This approach should be multimodal and seamlessly integrate other treatment approaches, including neurofeedback and transcranial electrical stimulation. This novel approach will involve the generation of software that engages the individual in an immersive and enjoyable game-based interface, integrated with advanced biosensing hardware, to maximally harness plasticity and assure adherence. Introducing such next-generation closed-loop neurocognitive therapeutics into the mainstream of our mental health care system will require the combined efforts of clinicians, neuroscientists, bioengineers, software game developers, and industry and policy makers working together to meet the challenges and opportunities of translational neuroscience in the 21st century. PMID:25520029

  14. EEG Indices Distinguish Spatial and Verbal Working Memory Processing: Implications for Real-Time Monitoring in a Closed-Loop Tactical Tomahawk Weapons Simulation

    DTIC Science & Technology

    2005-07-01

    Security Symposium, Biomonitoring for Physiological and Cognitive Performance During Military Operations, In Press. Matlin , M . W . (1998). Cognition ...cost” due to stimulus competition, ambiguity, or distractions (Baddeley, 2003; Matlin , 1998). Thus, it is essential to develop an understanding of...to a neural net that used a combination of physiological parameters to identify relevant cognitive state changes while operators performed the TTWCS

  15. Closed-Loop Neuromorphic Benchmarks

    PubMed Central

    Stewart, Terrence C.; DeWolf, Travis; Kleinhans, Ashley; Eliasmith, Chris

    2015-01-01

    Evaluating the effectiveness and performance of neuromorphic hardware is difficult. It is even more difficult when the task of interest is a closed-loop task; that is, a task where the output from the neuromorphic hardware affects some environment, which then in turn affects the hardware's future input. However, closed-loop situations are one of the primary potential uses of neuromorphic hardware. To address this, we present a methodology for generating closed-loop benchmarks that makes use of a hybrid of real physical embodiment and a type of “minimal” simulation. Minimal simulation has been shown to lead to robust real-world performance, while still maintaining the practical advantages of simulation, such as making it easy for the same benchmark to be used by many researchers. This method is flexible enough to allow researchers to explicitly modify the benchmarks to identify specific task domains where particular hardware excels. To demonstrate the method, we present a set of novel benchmarks that focus on motor control for an arbitrary system with unknown external forces. Using these benchmarks, we show that an error-driven learning rule can consistently improve motor control performance across a randomly generated family of closed-loop simulations, even when there are up to 15 interacting joints to be controlled. PMID:26696820

  16. Real-time radar signal processing for autonomous aircraft landing

    NASA Astrophysics Data System (ADS)

    Sadjadi, Firooz A.; Helgeson, Michael A.; Radke, Jeffrey D.; Stein, Gunter

    1993-11-01

    Landing in poor weather is a crucial problem for the air transportation system. To aid the pilots for these conditions several solutions have been suggested and/or implemented including instrument landing systems (ILS) and microwave landing systems (MLS) that put the responsibility of the landing to a large extent in the hands of the airport facilities. These systems even though useful are not available due to their high costs even in a few major metropolitan airports. This shortcoming has generated interest in providing all weather capabilities not on the landing facility but on the vehicle itself. The Synthetic Vision System Technology Demonstration sponsored by the United States Federal Aviation Administration (FAA) and the U.S. Air Force represents an effort to respond to the above needs. In this paper we present a summary of a typical synthetic vision system. This system consists of a scanning 35 GHz radar, a scanning antenna, a signal/image processor and a head up display (HUD). The pilot is presented a final perspective image of the scene sensed by the radar with associated flight guidance symbology. This system is implemented in real time hardware and has been undergoing tower and flight testing under a variety of weather conditions since early 1992.

  17. Nonlinear adaptive filter for closed-loop fire control

    NASA Astrophysics Data System (ADS)

    Marshall, William C.

    1990-09-01

    This paper presents an adaptive or self-learning filter design intended for use in real-time closed loop pointing control systems engaging multiple targets. The design approach is based upon use of a performance index (based upon the Mahalanobis generalized distance function) and multiple filters processed in parallel using the same nonlinear measurements as input. Application of performance index criteria to the statistics of individual filter residuals allows the selection of the optimum filter set without the time delays typically encountered and thereby allows the composite filter structure to adapt (or self-learn) to uncertainties in modeling target acceleration capabilities. An advantage of this approach is that it also provides to an operator (or a robotic controller) the confidence level of tracking system performance against a maneuvering target. This information is of interest for deployment of counter-measures (e.g., fire control eventing, alarms, engagement priority, etc) or simply for laboratory system tests of design adequacy.

  18. Real-time radar signal processing using GPGPU (general-purpose graphic processing unit)

    NASA Astrophysics Data System (ADS)

    Kong, Fanxing; Zhang, Yan Rockee; Cai, Jingxiao; Palmer, Robert D.

    2016-05-01

    This study introduces a practical approach to develop real-time signal processing chain for general phased array radar on NVIDIA GPUs(Graphical Processing Units) using CUDA (Compute Unified Device Architecture) libraries such as cuBlas and cuFFT, which are adopted from open source libraries and optimized for the NVIDIA GPUs. The processed results are rigorously verified against those from the CPUs. Performance benchmarked in computation time with various input data cube sizes are compared across GPUs and CPUs. Through the analysis, it will be demonstrated that GPGPUs (General Purpose GPU) real-time processing of the array radar data is possible with relatively low-cost commercial GPUs.

  19. Microgyroscope with closed loop output

    NASA Technical Reports Server (NTRS)

    Challoner, A. Dorian (Inventor); Gutierrez, Roman C. (Inventor); Tang, Tony K. (Inventor); Cargille, Donald R. (Inventor)

    2002-01-01

    A micro-gyroscope (10) having closed loop operation by a control voltage (V.sub.TY), that is demodulated by an output signal of the sense electrodes (S1, S2), providing Coriolis torque rebalance to prevent displacement of the micro-gyroscope (10) on the output axis (y-axis). The present invention provides wide-band, closed-loop operation for a micro-gyroscope (10) and allows the drive frequency to be closely tuned to a high Q sense axis resonance. A differential sense signal (S1-S2) is compensated and fed back by differentially changing the voltage on the drive electrodes to rebalance Coriolis torque. The feedback signal is demodulated in phase with the drive axis signal (K.sub..omega..crclbar..sub.x) to produce a measure of the Coriolis force.

  20. Falcon: a highly flexible open-source software for closed-loop neuroscience

    NASA Astrophysics Data System (ADS)

    Ciliberti, Davide; Kloosterman, Fabian

    2017-08-01

    Objective. Closed-loop experiments provide unique insights into brain dynamics and function. To facilitate a wide range of closed-loop experiments, we created an open-source software platform that enables high-performance real-time processing of streaming experimental data. Approach. We wrote Falcon, a C++ multi-threaded software in which the user can load and execute an arbitrary processing graph. Each node of a Falcon graph is mapped to a single thread and nodes communicate with each other through thread-safe buffers. The framework allows for easy implementation of new processing nodes and data types. Falcon was tested both on a 32-core and a 4-core workstation. Streaming data was read from either a commercial acquisition system (Neuralynx) or the open-source Open Ephys hardware, while closed-loop TTL pulses were generated with a USB module for digital output. We characterized the round-trip latency of our Falcon-based closed-loop system, as well as the specific latency contribution of the software architecture, by testing processing graphs with up to 32 parallel pipelines and eight serial stages. We finally deployed Falcon in a task of real-time detection of population bursts recorded live from the hippocampus of a freely moving rat. Main results. On Neuralynx hardware, round-trip latency was well below 1 ms and stable for at least 1 h, while on Open Ephys hardware latencies were below 15 ms. The latency contribution of the software was below 0.5 ms. Round-trip and software latencies were similar on both 32- and 4-core workstations. Falcon was used successfully to detect population bursts online with ~40 ms average latency. Significance. Falcon is a novel open-source software for closed-loop neuroscience. It has sub-millisecond intrinsic latency and gives the experimenter direct control of CPU resources. We envisage Falcon to be a useful tool to the neuroscientific community for implementing a wide variety of closed-loop experiments, including those

  1. Falcon: a highly flexible open-source software for closed-loop neuroscience.

    PubMed

    Ciliberti, Davide; Kloosterman, Fabian

    2017-05-26

    Closed-loop experiments provide unique insights into brain dynamics and function. To facilitate a wide range of closed-loop experiments, we created an open-source software platform that enables high-performance real-time processing of streaming experimental data. We wrote Falcon, a C++ multi-threaded software in which the user can load and execute an arbitrary processing graph. Each node of a Falcon graph is mapped to a single thread and nodes communicate with each other through thread-safe buffers. The framework allows for easy implementation of new processing nodes and data types. Falcon was tested both on a 32-core and a 4-core workstation. Streaming data was read from either a commercial acquisition system (Neuralynx) or the open-source Open Ephys hardware, while closed-loop TTL pulses were generated with a USB module for digital output. We characterized the round-trip latency of our Falcon-based closed-loop system, as well as the specific latency contribution of the software architecture, by testing processing graphs with up to 32 parallel pipelines and eight serial stages. We finally deployed Falcon in a task of real-time detection of population bursts recorded live from the hippocampus of a freely moving rat. On Neuralynx hardware, round-trip latency was well below 1 ms and stable for at least 1 h, while on Open Ephys hardware latencies were below 15 ms. The latency contribution of the software was below 0.5 ms. Round-trip and software latencies were similar on both 32- and 4-core workstations. Falcon was used successfully to detect population bursts online with ~40 ms average latency. Falcon is a novel open-source software for closed-loop neuroscience. It has sub-millisecond intrinsic latency and gives the experimenter direct control of CPU resources. We envisage Falcon to be a useful tool to the neuroscientific community for implementing a wide variety of closed-loop experiments, including those requiring use of complex data structures and real-time

  2. An architecture for heuristic control of real-time processes

    NASA Technical Reports Server (NTRS)

    Raulefs, P.; Thorndyke, P. W.

    1987-01-01

    Abstract Process management combines complementary approaches of heuristic reasoning and analytical process control. Management of a continuous process requires monitoring the environment and the controlled system, assessing the ongoing situation, developing and revising planned actions, and controlling the execution of the actions. For knowledge-intensive domains, process management entails the potentially time-stressed cooperation among a variety of expert systems. By redesigning a blackboard control architecture in an object-oriented framework, researchers obtain an approach to process management that considerably extends blackboard control mechanisms and overcomes limitations of blackboard systems.

  3. Process data acquisition: Real time and historical interfaces

    SciTech Connect

    Rice, G.; Moreno, R.; King, M.

    1996-11-01

    With the advent of touch probe technology, it was discovered that current closed architecture controllers do not provide adequate resources to support the implementation of process data acquisition on the shop floor. At AlliedSignal Federal Manufacturing & Technologies, a process data acquisition system has been developed for a flexible manufacturing system utilizing touch probes and customized software which allows fixture and cutting tool related information for an entire process to be captured and stored for off-line analysis. The implementation of this system, the difficulties and pitfalls, will be presented along with the functionality required for an open architecture controller to properly support process data acquisition.

  4. Design of a recursive filter for infrared image real-time processing

    NASA Astrophysics Data System (ADS)

    Zhou, Bing; Zhou, Zhongliang; He, Yongqiang

    2008-03-01

    A real-time recursive filtering processor using the core of digital commix chip HSP48212 was presented and designed assisted by FIFO memorizer and CPLD logic parse circuit, which realized real-time recursive filtering of 12bit infrared image. It has much notable virtue such as simple structure, strong real-time capability, controllable logic during operation process, and synchronal clock. It used in infrared fish-eye staring reconnaissance system for image real-time reduce noise and obtain perfect effect.

  5. Derivation of sequential, real-time, process-control programs

    NASA Technical Reports Server (NTRS)

    Marzullo, Keith; Schneider, Fred B.; Budhiraja, Navin

    1991-01-01

    The use of weakest-precondition predicate transformers in the derivation of sequential, process-control software is discussed. Only one extension to Dijkstra's calculus for deriving ordinary sequential programs was found to be necessary: function-valued auxiliary variables. These auxiliary variables are needed for reasoning about states of a physical process that exists during program transitions.

  6. Medical Image Processing Using Real-Time Optical Fourier Technique

    NASA Astrophysics Data System (ADS)

    Rao, D. V. G. L. N.; Panchangam, Appaji; Sastry, K. V. L. N.; Material Science Team

    2001-03-01

    Optical Image Processing Techniques are inherently fast in view of parallel processing. A self-adaptive Optical Fourier Processing system using photo induced dichroism in a Bacteriorhodopsin film was experimentally demonstrated for medical image processing. Application of this powerful analog all-optical interactive technique for cancer diagnostics is illustrated with mammograms and Pap smears. Micro calcification clusters buried in surrounding tissue showed up clearly in the processed image. By playing with one knob, which rotates the analyzer in the optical system, either the micro calcification clusters or the surrounding dense tissue can be selectively displayed. Bacteriorhodopsin films are stable up to 140^oC and environmental friendly. As no interference is involved in the experiments, vibration isolation and even a coherent light source are not required. It may be possible to develop a low-cost rugged battery operated portable signal-enhancing magnifier.

  7. Yield enhancement through monitoring of real-time manufacturing processes

    NASA Astrophysics Data System (ADS)

    Henis, Neil B.; Satterfield, Michael J.; Travis, Edward O.; Gelatos, Carol

    1994-09-01

    One of the major sources of particles today is from processing equipment. As die size continues to shrink, more effort needs to be placed in defect detection and elimination. A defect of 1 - 2 microns in size, while barely noticeable 5 years ago, can now destroy an entire die. Even with redundancy, a metal defect 1 micron in size will result in excess leakage due to an array short. While missing metal may be repairable, metal flakes from sputtering machines, for example, result in nonrepairable die. The objective of this paper is to show how backend defect reduction and yield enhancement can be improved with the use of the newer defect detection tools. We discuss three defect problems at different process levels which were discovered and eliminated with this work. The term `process induced defects per wafer pass' (PIDPWP) is demonstrated.

  8. The Real-Time Processing of Sluiced Sentences

    ERIC Educational Resources Information Center

    Poirier, Josee; Wolfinger, Katie; Spellman, Lisa; Shapiro, Lewis P.

    2010-01-01

    Ellipsis refers to an element that is absent from the input but whose meaning can nonetheless be recovered from context. In this cross-modal priming study, we examined the online processing of Sluicing, an ellipsis whose antecedent is an entire clause: "The handyman threw a book to the programmer but I don't know which book" the handyman threw to…

  9. Real-Time Implementation of Nonlinear Processing Functions.

    DTIC Science & Technology

    1981-08-01

    crystal devices and then to use them in a coherent optical data- processing apparatus using halftone masks custom designed at the University oi Southern...California. With the halftone mask technique, we have demonstrated logarithmic nonlinear transformation, allowing us to separate multiplicative images...improved.,_ This device allowed nonlinear functions to be implemented directly wit - out the need for specially made halftone masks. Besides

  10. Implementing spiking neural networks for real-time signal-processing and control applications: a model-validated FPGA approach.

    PubMed

    Pearson, Martin J; Pipe, A G; Mitchinson, B; Gurney, K; Melhuish, C; Gilhespy, I; Nibouche, M

    2007-09-01

    In this paper, we present two versions of a hardware processing architecture for modeling large networks of leaky-integrate-and-fire (LIF) neurons; the second version provides performance enhancing features relative to the first. Both versions of the architecture use fixed-point arithmetic and have been implemented using a single field-programmable gate array (FPGA). They have successfully simulated networks of over 1000 neurons configured using biologically plausible models of mammalian neural systems. The neuroprocessor has been designed to be employed primarily for use on mobile robotic vehicles, allowing bio-inspired neural processing models to be integrated directly into real-world control environments. When a neuroprocessor has been designed to act as part of the closed-loop system of a feedback controller, it is imperative to maintain strict real-time performance at all times, in order to maintain integrity of the control system. This resulted in the reevaluation of some of the architectural features of existing hardware for biologically plausible neural networks (NNs). In addition, we describe a development system for rapidly porting an underlying model (based on floating-point arithmetic) to the fixed-point representation of the FPGA-based neuroprocessor, thereby allowing validation of the hardware architecture. The developmental system environment facilitates the cooperation of computational neuroscientists and engineers working on embodied (robotic) systems with neural controllers, as demonstrated by our own experience on the Whiskerbot project, in which we developed models of the rodent whisker sensory system.

  11. Reducing lumber thickness variation using real-time statistical process control

    Treesearch

    Thomas M. Young; Brian H. Bond; Jan Wiedenbeck

    2002-01-01

    A technology feasibility study for reducing lumber thickness variation was conducted from April 2001 until March 2002 at two sawmills located in the southern U.S. A real-time statistical process control (SPC) system was developed that featured Wonderware human machine interface technology (HMI) with distributed real-time control charts for all sawing centers and...

  12. Method and system for enabling real-time speckle processing using hardware platforms

    NASA Technical Reports Server (NTRS)

    Ortiz, Fernando E. (Inventor); Kelmelis, Eric (Inventor); Durbano, James P. (Inventor); Curt, Peterson F. (Inventor)

    2012-01-01

    An accelerator for the speckle atmospheric compensation algorithm may enable real-time speckle processing of video feeds that may enable the speckle algorithm to be applied in numerous real-time applications. The accelerator may be implemented in various forms, including hardware, software, and/or machine-readable media.

  13. Real-time visual processing in support of autonomous driving

    NASA Astrophysics Data System (ADS)

    Nashman, Marilyn; Schneiderman, Henry

    1997-02-01

    Autonomous driving provides an effective way to address traffic concerns such as safety and congestion. There has been increasing interest in the development of autonomous driving in recent years. Interest has included high-speed driving on highways, urban driving, and navigation through less structured off-road environments. The primary challenge in autonomous driving is developing perception techniques that are reliable under the extreme variability of outdoor conditions in any of these environments. Roads vary in appearance. Some are smooth and well marked, while others have cracks and potholes or are unmarked. Shadows, glare, varying illumination, dirt or foreign matter, other vehicles, rain, and snow also affect road appearance. This paper describes a visual processing algorithm that supports autonomous driving. The algorithm requires that lane markings be present and attempts to track the lane markings on each of two lane boundaries in the lane of travel. There are three stages of visual processing computation: extracting edges, determining which edges correspond to lane markers, and updating geometric models of the lane markers. A fourth stage computes a steering command for the vehicle based on the updated road model. All processing is confined to the 2-D image plane. No information about the motion of the vehicle is used. This algorithm has been used as part of a complete system to drive an autonomous vehicle, a high mobility multipurpose wheeled vehicle (HMMWV). Autonomous driving has been demonstrated on both local roads and highways at speeds up to 100 kilometers per hour (km/h). The algorithm has performed well in the presence of non-ideal road conditions including gaps in the lane markers, sharp curves, shadows, cracks in the pavement, wet roads, rain, dusk, and nighttime driving. The algorithm runs at a sampling rate of 15 Hz and has a worst case processing delay time of 150 milliseconds. Processing is implemented under the NASA/NBS Standard

  14. Using real time process measurements to reduce catheter related bloodstream infections in the intensive care unit

    PubMed Central

    Wall, R; Ely, E; Elasy, T; Dittus, R; Foss, J; Wilkerson, K; Speroff, T

    2005-01-01

    

Problem: Measuring a process of care in real time is essential for continuous quality improvement (CQI). Our inability to measure the process of central venous catheter (CVC) care in real time prevented CQI efforts aimed at reducing catheter related bloodstream infections (CR-BSIs) from these devices. Design: A system was developed for measuring the process of CVC care in real time. We used these new process measurements to continuously monitor the system, guide CQI activities, and deliver performance feedback to providers. Setting: Adult medical intensive care unit (MICU). Key measures for improvement: Measured process of CVC care in real time; CR-BSI rate and time between CR-BSI events; and performance feedback to staff. Strategies for change: An interdisciplinary team developed a standardized, user friendly nursing checklist for CVC insertion. Infection control practitioners scanned the completed checklists into a computerized database, thereby generating real time measurements for the process of CVC insertion. Armed with these new process measurements, the team optimized the impact of a multifaceted intervention aimed at reducing CR-BSIs. Effects of change: The new checklist immediately provided real time measurements for the process of CVC insertion. These process measures allowed the team to directly monitor adherence to evidence-based guidelines. Through continuous process measurement, the team successfully overcame barriers to change, reduced the CR-BSI rate, and improved patient safety. Two years after the introduction of the checklist the CR-BSI rate remained at a historic low. Lessons learnt: Measuring the process of CVC care in real time is feasible in the ICU. When trying to improve care, real time process measurements are an excellent tool for overcoming barriers to change and enhancing the sustainability of efforts. To continually improve patient safety, healthcare organizations should continually measure their key clinical processes in real

  15. Multi-user real-time speech processing facility

    NASA Astrophysics Data System (ADS)

    Pisoni, D. B.

    1985-03-01

    Research projects requiring the VAX 11/750 and related peripherals have all focused on speech analysis, perception and recognition. We compared perceptual confusions occurring for natural and synthetic speech syllables which showed that synthetic speech is not equivalent to noisy or degraded natural speech. We conducted a study that indicated that perception of synthetic speech is improved by training. Training with fluent synthetic sentences improves performance for both isolated words and sentences. Training with isolated words improves performance on isolated words but does not improve performance on fluent synthetic sentences. A large-scale series of experiments investigated the effects of noise in a talker's ears on speech production. Words produced in noise are longer, louder and higher in pitch than words produced in the quiet. The tilt of the power spectrum decreased and formant frequencies shifted in noise. nition, I/O, human factors, cognitive processes, and communication sciences.

  16. Real-time garbage collection for list processing

    NASA Technical Reports Server (NTRS)

    Shuler, R. L., Jr. (Inventor)

    1986-01-01

    In a list processing system, small reference counters are maintained in conjunction with memory cells for the purpose of identifying memory cells that become available for re-use. The counters are updated as references to the cells are created and destroyed, and when a counter of a cell is decremented to logical zero the cell is immediately returned to a list of free cells. In those cases where a counter must be incremented beyond the maximum value that can be represented in a small counter, the cell is restructured so that the additional reference count can be represented. The restructuring involves allocating an additional cell, distributing counter, tag, and pointer information among the two cells, and linking both cells appropriately into the existing list structure.

  17. Closed-Loop Attention Management: Using Augmented Cognition to Sustain Vigilance

    DTIC Science & Technology

    2008-12-01

    CLOSED-LOOP ATTENTION MANAGEMENT: USING AUGMENTED COGNITION TO SUSTAIN VIGILANCE Mark St. John* & Matthew R. Risser Pacific Science...sustained vigilance via a closed-loop attention management system (CLAM). A CLAM system monitors operators’ psychophysiology for signs of inattention and...successful real- time detection of inattention and an effective countermeasure for rousing participants and sustaining vigilance and task performance. The

  18. Expert system and process optimization techniques for real-time monitoring and control of plasma processes

    NASA Astrophysics Data System (ADS)

    Cheng, Jie; Qian, Zhaogang; Irani, Keki B.; Etemad, Hossein; Elta, Michael E.

    1991-03-01

    To meet the ever-increasing demand of the rapidly-growing semiconductor manufacturing industry it is critical to have a comprehensive methodology integrating techniques for process optimization real-time monitoring and adaptive process control. To this end we have accomplished an integrated knowledge-based approach combining latest expert system technology machine learning method and traditional statistical process control (SPC) techniques. This knowledge-based approach is advantageous in that it makes it possible for the task of process optimization and adaptive control to be performed consistently and predictably. Furthermore this approach can be used to construct high-level and qualitative description of processes and thus make the process behavior easy to monitor predict and control. Two software packages RIST (Rule Induction and Statistical Testing) and KARSM (Knowledge Acquisition from Response Surface Methodology) have been developed and incorporated with two commercially available packages G2 (real-time expert system) and ULTRAMAX (a tool for sequential process optimization).

  19. Human movement analysis with image processing in real time

    NASA Astrophysics Data System (ADS)

    Fauvet, Eric; Paindavoine, Michel; Cannard, F.

    1991-04-01

    In the field of the human sciences, a lot of applications needs to know the kinematic characteristics of the human movements Psycology is associating the characteristics with the control mechanism, sport and biomechariics are associating them with the performance of the sportman or of the patient. So the trainers or the doctors can correct the gesture of the subject to obtain a better performance if he knows the motion properties. Roherton's studies show the children motion evolution2 . Several investigations methods are able to measure the human movement But now most of the studies are based on image processing. Often the systems are working at the T.V. standard (50 frame per secund ). they permit only to study very slow gesture. A human operator analyses the digitizing sequence of the film manually giving a very expensive, especially long and unprecise operation. On these different grounds many human movement analysis systems were implemented. They consist of: - markers which are fixed to the anatomical interesting points on the subject in motion, - Image compression which is the art to coding picture data. Generally the compression Is limited to the centroid coordinates calculation tor each marker. These systems differ from one other in image acquisition and markers detection.

  20. Delay-Dependent Response in Weakly Electric Fish under Closed-Loop Pulse Stimulation.

    PubMed

    Forlim, Caroline Garcia; Pinto, Reynaldo Daniel; Varona, Pablo; Rodríguez, Francisco B

    2015-01-01

    In this paper, we apply a real time activity-dependent protocol to study how freely swimming weakly electric fish produce and process the timing of their own electric signals. Specifically, we address this study in the elephant fish, Gnathonemus petersii, an animal that uses weak discharges to locate obstacles or food while navigating, as well as for electro-communication with conspecifics. To investigate how the inter pulse intervals vary in response to external stimuli, we compare the response to a simple closed-loop stimulation protocol and the signals generated without electrical stimulation. The activity-dependent stimulation protocol explores different stimulus delivery delays relative to the fish's own electric discharges. We show that there is a critical time delay in this closed-loop interaction, as the largest changes in inter pulse intervals occur when the stimulation delay is below 100 ms. We also discuss the implications of these findings in the context of information processing in weakly electric fish.

  1. [Near infrared spectroscopy and multivariate statistical process analysis for real-time monitoring of production process].

    PubMed

    Wang, Yi; Ma, Xiang; Wen, Ya-Dong; Zou, Quan; Wang, Jun; Tu, Jia-Run; Cai, Wen-Sheng; Shao, Xue-Guang

    2013-05-01

    Near infrared diffusive reflectance spectroscopy has been applied in on-site or on-line analysis due to its characteristics of fastness, non-destruction and the feasibility for real complex sample analysis. The present work reported a real-time monitoring method for industrial production by using near infrared spectroscopic technique and multivariate statistical process analysis. In the method, the real-time near infrared spectra of the materials are collected on the production line, and then the evaluation of the production process can be achieved by a statistic Hotelling T2 calculated with the established model. In this work, principal component analysis (PCA) is adopted for building the model, and the statistic is calculated by projecting the real-time spectra onto the PCA model. With an application of the method in a practical production, it was demonstrated that a real-time evaluation of the variations in the production can be realized by investigating the changes in the statistic, and the comparison of the products in different batches can be achieved by further statistics of the statistic. Therefore, the proposed method may provide a practical way for quality insurance of production processes.

  2. Closed-Loop, Multichannel Experimentation Using the Open-Source NeuroRighter Electrophysiology Platform

    PubMed Central

    Newman, Jonathan P.; Zeller-Townson, Riley; Fong, Ming-Fai; Arcot Desai, Sharanya; Gross, Robert E.; Potter, Steve M.

    2013-01-01

    Single neuron feedback control techniques, such as voltage clamp and dynamic clamp, have enabled numerous advances in our understanding of ion channels, electrochemical signaling, and neural dynamics. Although commercially available multichannel recording and stimulation systems are commonly used for studying neural processing at the network level, they provide little native support for real-time feedback. We developed the open-source NeuroRighter multichannel electrophysiology hardware and software platform for closed-loop multichannel control with a focus on accessibility and low cost. NeuroRighter allows 64 channels of stimulation and recording for around US $10,000, along with the ability to integrate with other software and hardware. Here, we present substantial enhancements to the NeuroRighter platform, including a redesigned desktop application, a new stimulation subsystem allowing arbitrary stimulation patterns, low-latency data servers for accessing data streams, and a new application programming interface (API) for creating closed-loop protocols that can be inserted into NeuroRighter as plugin programs. This greatly simplifies the design of sophisticated real-time experiments without sacrificing the power and speed of a compiled programming language. Here we present a detailed description of NeuroRighter as a stand-alone application, its plugin API, and an extensive set of case studies that highlight the system’s abilities for conducting closed-loop, multichannel interfacing experiments. PMID:23346047

  3. Virtual Grasping: Closed-Loop Force Control Using Electrotactile Feedback

    PubMed Central

    Jorgovanovic, Nikola; Dosen, Strahinja; Djozic, Damir J.; Krajoski, Goran; Farina, Dario

    2014-01-01

    Closing the control loop by providing somatosensory feedback to the user of a prosthesis is a well-known, long standing challenge in the field of prosthetics. Various approaches have been investigated for feedback restoration, ranging from direct neural stimulation to noninvasive sensory substitution methods. Although there are many studies presenting closed-loop systems, only a few of them objectively evaluated the closed-loop performance, mostly using vibrotactile stimulation. Importantly, the conclusions about the utility of the feedback were partly contradictory. The goal of the current study was to systematically investigate the capability of human subjects to control grasping force in closed loop using electrotactile feedback. We have developed a realistic experimental setup for virtual grasping, which operated in real time, included a set of real life objects, as well as a graphical and dynamical model of the prosthesis. We have used the setup to test 10 healthy, able bodied subjects to investigate the role of training, feedback and feedforward control, robustness of the closed loop, and the ability of the human subjects to generalize the control to previously “unseen” objects. Overall, the outcomes of this study are very optimistic with regard to the benefits of feedback and reveal various, practically relevant, aspects of closed-loop control. PMID:24516504

  4. Virtual grasping: closed-loop force control using electrotactile feedback.

    PubMed

    Jorgovanovic, Nikola; Dosen, Strahinja; Djozic, Damir J; Krajoski, Goran; Farina, Dario

    2014-01-01

    Closing the control loop by providing somatosensory feedback to the user of a prosthesis is a well-known, long standing challenge in the field of prosthetics. Various approaches have been investigated for feedback restoration, ranging from direct neural stimulation to noninvasive sensory substitution methods. Although there are many studies presenting closed-loop systems, only a few of them objectively evaluated the closed-loop performance, mostly using vibrotactile stimulation. Importantly, the conclusions about the utility of the feedback were partly contradictory. The goal of the current study was to systematically investigate the capability of human subjects to control grasping force in closed loop using electrotactile feedback. We have developed a realistic experimental setup for virtual grasping, which operated in real time, included a set of real life objects, as well as a graphical and dynamical model of the prosthesis. We have used the setup to test 10 healthy, able bodied subjects to investigate the role of training, feedback and feedforward control, robustness of the closed loop, and the ability of the human subjects to generalize the control to previously "unseen" objects. Overall, the outcomes of this study are very optimistic with regard to the benefits of feedback and reveal various, practically relevant, aspects of closed-loop control.

  5. Real-time plasma process condition sensing and abnormal process detection.

    PubMed

    Yang, Ryan; Chen, Rongshun

    2010-01-01

    The plasma process is often used in the fabrication of semiconductor wafers. However, due to the lack of real-time etching control, this may result in some unacceptable process performances and thus leads to significant waste and lower wafer yield. In order to maximize the product wafer yield, a timely and accurately process fault or abnormal detection in a plasma reactor is needed. Optical emission spectroscopy (OES) is one of the most frequently used metrologies in in-situ process monitoring. Even though OES has the advantage of non-invasiveness, it is required to provide a huge amount of information. As a result, the data analysis of OES becomes a big challenge. To accomplish real-time detection, this work employed the sigma matching method technique, which is the time series of OES full spectrum intensity. First, the response model of a healthy plasma spectrum was developed. Then, we defined a matching rate as an indictor for comparing the difference between the tested wafers response and the health sigma model. The experimental results showed that this proposal method can detect process faults in real-time, even in plasma etching tools.

  6. Real-Time Plasma Process Condition Sensing and Abnormal Process Detection

    PubMed Central

    Yang, Ryan; Chen, Rongshun

    2010-01-01

    The plasma process is often used in the fabrication of semiconductor wafers. However, due to the lack of real-time etching control, this may result in some unacceptable process performances and thus leads to significant waste and lower wafer yield. In order to maximize the product wafer yield, a timely and accurately process fault or abnormal detection in a plasma reactor is needed. Optical emission spectroscopy (OES) is one of the most frequently used metrologies in in-situ process monitoring. Even though OES has the advantage of non-invasiveness, it is required to provide a huge amount of information. As a result, the data analysis of OES becomes a big challenge. To accomplish real-time detection, this work employed the sigma matching method technique, which is the time series of OES full spectrum intensity. First, the response model of a healthy plasma spectrum was developed. Then, we defined a matching rate as an indictor for comparing the difference between the tested wafers response and the health sigma model. The experimental results showed that this proposal method can detect process faults in real-time, even in plasma etching tools. PMID:22219683

  7. Process synchronization and data communication between processes in real time local area networks

    NASA Astrophysics Data System (ADS)

    Haeger, R.

    1985-12-01

    This thesis extends the multi-computer real-time executive, MCORTEX. The multiple cluster system RTC (Real Time Cluster Star), consisting of clusters of single board computers (INTEL iSBC 86/12A), which are connected via an Ethernet Local Area Network, serves as a hardware basis for the implementation of extended MCORTEX. The extension upgrades MCORTEX to system-wide synchronization and general data communication between any processes in the system. An intercluster shared memory model is developed, that partially replicates intracluster shared memory, such that shared data replication is minimized and the system's processing speed is maximized. This implementation, by transmitting produced shared data to all consuming clusters as soon as possible after production, guarantees that only cluster local hits occur in the system. Shared memory space is used efficiently by transmitting shared data to consuming clusters only, and by the ability to store shared data contiguously in intracluster shared memory.

  8. Closed-Loop Analysis of Soft Decisions for Serial Links

    NASA Technical Reports Server (NTRS)

    Lansdowne, Chatwin A.; Steele, Glen F.; Zucha, Joan P.; Schlensinger, Adam M.

    2012-01-01

    Modern receivers are providing soft decision symbol synchronization as radio links are challenged to push more data and more overhead through noisier channels, and software-defined radios use error-correction techniques that approach Shannon s theoretical limit of performance. The authors describe the benefit of closed-loop measurements for a receiver when paired with a counterpart transmitter and representative channel conditions. We also describe a real-time Soft Decision Analyzer (SDA) implementation for closed-loop measurements on single- or dual- (orthogonal) channel serial data communication links. The analyzer has been used to identify, quantify, and prioritize contributors to implementation loss in real-time during the development of software defined radios.

  9. Real-time digital signal processing for live electro-optic imaging.

    PubMed

    Sasagawa, Kiyotaka; Kanno, Atsushi; Tsuchiya, Masahiro

    2009-08-31

    We present an imaging system that enables real-time magnitude and phase detection of modulated signals and its application to a Live Electro-optic Imaging (LEI) system, which realizes instantaneous visualization of RF electric fields. The real-time acquisition of magnitude and phase images of a modulated optical signal at 5 kHz is demonstrated by imaging with a Si-based high-speed CMOS image sensor and real-time signal processing with a digital signal processor. In the LEI system, RF electric fields are probed with light via an electro-optic crystal plate and downconverted to an intermediate frequency by parallel optical heterodyning, which can be detected with the image sensor. The artifacts caused by the optics and the image sensor characteristics are corrected by image processing. As examples, we demonstrate real-time visualization of electric fields from RF circuits.

  10. AUTOMATED CONTROL AND REAL-TIME DATA PROCESSING OF WIRE SCANNER/HALO SCRAPER MEASUREMENTS

    SciTech Connect

    L.A. DAY; J.D. GILPATRICK; ET AL

    2001-06-01

    The Low-Energy Demonstration Accelerator (LEDA), assembled and operating at Los Alamos National Laboratory, provides the platform for obtaining measurements of high-power proton beam-halo formation. Control system software and hardware have been integrated and customized to enable the production of real-time beam-halo profiles. The Experimental Physics and Industrial Control System (EPICS) hosted on a VXI platform, Interactive Data Language (IDL) programs hosted on UNIX platforms, and LabVIEW (LV) Virtual Instruments hosted on a PC platform have been integrated and customized to provide real-time, synchronous motor control, data acquisition, and data analysis of data acquired through specialized DSP instrumentation. These modules communicate through EPICS Channel Access (CA) communication protocol extensions to control and manage execution flow ensuring synchronous data acquisition and real-time processing of measurement data. This paper describes the software integration and management scheme implemented to produce these real-time beam profiles.

  11. Hardware System for Real-Time EMG Signal Acquisition and Separation Processing during Electrical Stimulation.

    PubMed

    Hsueh, Ya-Hsin; Yin, Chieh; Chen, Yan-Hong

    2015-09-01

    The study aimed to develop a real-time electromyography (EMG) signal acquiring and processing device that can acquire signal during electrical stimulation. Since electrical stimulation output can affect EMG signal acquisition, to integrate the two elements into one system, EMG signal transmitting and processing method has to be modified. The whole system was designed in a user-friendly and flexible manner. For EMG signal processing, the system applied Altera Field Programmable Gate Array (FPGA) as the core to instantly process real-time hybrid EMG signal and output the isolated signal in a highly efficient way. The system used the power spectral density to evaluate the accuracy of signal processing, and the cross correlation showed that the delay of real-time processing was only 250 μs.

  12. Optical signal processing and tracking of whispering gallery modes in real-time for sensing applications

    NASA Astrophysics Data System (ADS)

    Ali, Amir R.; Afifi, Amr N.; Taha, Hazem

    2017-05-01

    A novel approach for tracking of whispering gallery modes (WGM) in real-time for dielectric cavities used in sensing application is presented in this paper. Real-time tracking for the shifts of the WGM can be used to measure the physical quantity of interest precisely, under high repetition rates. The tracking algorithm is based on cross-correlation signal processing technique which has been proved to be accurate in WGM shifts detection. In order to achieve portability, the aforementioned real-time algorithm is implemented using a single-board re-configurable input-output hardware. The hardware platform used combines a real-time processor and a field programmable gate array (FPGA), it also allows for data exchange between them. The tracking algorithm's accuracy and real-time behavior is verified by preforming simulations based on experiments conducted on the dielectric cavity, where the cavity is used as a force sensor measuring mechanical compression. The light from a laser diode is tuned with rates up to 10 kHz and then tangentially coupled into the cavity to excite the WGM. Results show that shifts of the WGM are tracked by the algorithm providing real-time force readings.

  13. Real-time image processing for non-contact monitoring of dynamic displacements using smartphone technologies

    NASA Astrophysics Data System (ADS)

    Min, Jae-Hong; Gelo, Nikolas J.; Jo, Hongki

    2016-04-01

    The newly developed smartphone application, named RINO, in this study allows measuring absolute dynamic displacements and processing them in real time using state-of-the-art smartphone technologies, such as high-performance graphics processing unit (GPU), in addition to already powerful CPU and memories, embedded high-speed/ resolution camera, and open-source computer vision libraries. A carefully designed color-patterned target and user-adjustable crop filter enable accurate and fast image processing, allowing up to 240fps for complete displacement calculation and real-time display. The performances of the developed smartphone application are experimentally validated, showing comparable accuracy with those of conventional laser displacement sensor.

  14. Simple all-optical FFT scheme enabling Tbit/s real-time signal processing.

    PubMed

    Hillerkuss, D; Winter, M; Teschke, M; Marculescu, A; Li, J; Sigurdsson, G; Worms, K; Ben Ezra, S; Narkiss, N; Freude, W; Leuthold, J

    2010-04-26

    A practical scheme to perform the fast Fourier transform in the optical domain is introduced. Optical real-time FFT signal processing is performed at speeds far beyond the limits of electronic digital processing, and with negligible energy consumption. To illustrate the power of the method we demonstrate an optical 400 Gbit/s OFDM receiver. It performs an optical real-time FFT on the consolidated OFDM data stream, thereby demultiplexing the signal into lower bit rate subcarrier tributaries, which can then be processed electronically.

  15. Real-time processing of EMG signals for bionic arm purposes

    NASA Astrophysics Data System (ADS)

    Olid Dominguez, Ferran; Wawrzyniak, Zbigniew M.

    2016-09-01

    This paper is connected with the problem of prostheses, that have always been a necessity for the human being. Bio-physiological signals from muscles, electromyographic signals have been collected, analyzed and processed in order to implement a real-time algorithm which is capable of differentiation of two different states of a bionic hand: open and closed. An algorithm for real-time electromyographic signal processing with almost no false positives is presented and it is explained that in bio-physiological experiments proper signal processing is of great importance.

  16. Off-axis quantitative phase imaging processing using CUDA: toward real-time applications.

    PubMed

    Pham, Hoa; Ding, Huafeng; Sobh, Nahil; Do, Minh; Patel, Sanjay; Popescu, Gabriel

    2011-07-01

    We demonstrate real time off-axis Quantitative Phase Imaging (QPI) using a phase reconstruction algorithm based on NVIDIA's CUDA programming model. The phase unwrapping component is based on Goldstein's algorithm. By mapping the process of extracting phase information and unwrapping to GPU, we are able to speed up the whole procedure by more than 18.8× with respect to CPU processing and ultimately achieve video rate for mega-pixel images. Our CUDA implementation also supports processing of multiple images simultaneously. This enables our imaging system to support high speed, high throughput, and real-time image acquisition and visualization.

  17. Off-axis quantitative phase imaging processing using CUDA: toward real-time applications

    PubMed Central

    Pham, Hoa; Ding, Huafeng; Sobh, Nahil; Do, Minh; Patel, Sanjay; Popescu, Gabriel

    2011-01-01

    We demonstrate real time off-axis Quantitative Phase Imaging (QPI) using a phase reconstruction algorithm based on NVIDIA’s CUDA programming model. The phase unwrapping component is based on Goldstein’s algorithm. By mapping the process of extracting phase information and unwrapping to GPU, we are able to speed up the whole procedure by more than 18.8× with respect to CPU processing and ultimately achieve video rate for mega-pixel images. Our CUDA implementation also supports processing of multiple images simultaneously. This enables our imaging system to support high speed, high throughput, and real-time image acquisition and visualization. PMID:21750757

  18. Closed-Loop Control System for Friction Stir Welding Retractable Pin Tool

    NASA Technical Reports Server (NTRS)

    Ding, R. Jeffrey; Romine, Peter L.; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    NASA invention disclosure, NASA Case No. MFS-31413, entitled "System for Controlling the Stirring Pin of a Friction Stir Welding Apparatus", (Patent Pending) authored by Jeff Ding, Dr Peter Romine and Pete Oelgoetz, addresses the precision control of the friction stir welding process. The closed-loop control system automatically adjusts the spinning welding pin, real-time, to maintain a precise penetration ligament (i.e., distance between pin-tip and weld panel backside surface). A specific pin length can be maintained while welding constant thickness or tapered material thickness weld panels. The closed-loop control system provides operator data and information relative to the exact position of the welding pin inside the weld joint. This paper presents the closed-loop RPT control system that operates using the auto-feedback of force signals sensed by the tip and shoulder of the welding pin. Significance: The FSW process can be successfully used in a production environment only if there is a method or technique that informs the FSW operator the precise location of the welding pin inside the weld joint. This is essential for applications in aerospace, automotive, pressure vessel, commercial aircraft and other industries.

  19. Closed-Loop Control System for Friction Stir Welding Retractable Pin Tool

    NASA Technical Reports Server (NTRS)

    Ding, R. Jeffrey; Romine, Peter L.; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    NASA invention disclosure, NASA Case No. MFS-31413, entitled "System for Controlling the Stirring Pin of a Friction Stir Welding Apparatus", (Patent Pending) authored by Jeff Ding, Dr Peter Romine and Pete Oelgoetz, addresses the precision control of the friction stir welding process. The closed-loop control system automatically adjusts the spinning welding pin, real-time, to maintain a precise penetration ligament (i.e., distance between pin-tip and weld panel backside surface). A specific pin length can be maintained while welding constant thickness or tapered material thickness weld panels. The closed-loop control system provides operator data and information relative to the exact position of the welding pin inside the weld joint. This paper presents the closed-loop RPT control system that operates using the auto-feedback of force signals sensed by the tip and shoulder of the welding pin. Significance: The FSW process can be successfully used in a production environment only if there is a method or technique that informs the FSW operator the precise location of the welding pin inside the weld joint. This is essential for applications in aerospace, automotive, pressure vessel, commercial aircraft and other industries.

  20. Passive Identification is Non Stationary Objects With Closed Loop Control

    NASA Astrophysics Data System (ADS)

    Dyadik, Valeriy F.; Nadezhdin, Igor S.; Goryunov, Alexey G.; Manenti, Flavio

    2016-08-01

    Typically chemical processes have significant nonlinear dynamics, but despite this, industry is conventionally still using PID-based regulatory control systems. Moreover, process units are interconnected, in terms of inlet and outlet material/energy flows, to other neighbouring units, thus their dynamic behaviour is strongly influenced by these connections and, as a consequence, conventional control systems performance often proves to be poor. However, there a hybrid fuzzy PID control logic, whose tuning parameters are provided in real time. The fuzzy controller tuning is made on the basis of Mamdani controller, also exploiting the results coming from an identification procedure that is carried on when an unmeasured step disturbance of any shape affects the process behaviour. This paper presents procedure for identifying technological object control in a closed loop, i. e. that operates the automated control system. The variation in the controlled variable, caused by the change of the nonmeasurable disturbance, is considered the initial signal for the identification procedure. The parameters of the control object are found by optimization method Levenberg-Marquardt.

  1. A customizable system for real-time image processing using the Blackfin DSProcessor and the MicroC/OS-II real-time kernel

    NASA Astrophysics Data System (ADS)

    Coffey, Stephen; Connell, Joseph

    2005-06-01

    This paper presents a development platform for real-time image processing based on the ADSP-BF533 Blackfin processor and the MicroC/OS-II real-time operating system (RTOS). MicroC/OS-II is a completely portable, ROMable, pre-emptive, real-time kernel. The Blackfin Digital Signal Processors (DSPs), incorporating the Analog Devices/Intel Micro Signal Architecture (MSA), are a broad family of 16-bit fixed-point products with a dual Multiply Accumulate (MAC) core. In addition, they have a rich instruction set with variable instruction length and both DSP and MCU functionality thus making them ideal for media based applications. Using the MicroC/OS-II for task scheduling and management, the proposed system can capture and process raw RGB data from any standard 8-bit greyscale image sensor in soft real-time and then display the processed result using a simple PC graphical user interface (GUI). Additionally, the GUI allows configuration of the image capture rate and the system and core DSP clock rates thereby allowing connectivity to a selection of image sensors and memory devices. The GUI also allows selection from a set of image processing algorithms based in the embedded operating system.

  2. Error analysis of real time and post processed or bit determination of GFO using GPS tracking

    NASA Technical Reports Server (NTRS)

    Schreiner, William S.

    1991-01-01

    The goal of the Navy's GEOSAT Follow-On (GFO) mission is to map the topography of the world's oceans in both real time (operational) and post processed modes. Currently, the best candidate for supplying the required orbit accuracy is the Global Positioning System (GPS). The purpose of this fellowship was to determine the expected orbit accuracy for GFO in both the real time and post-processed modes when using GPS tracking. This report presents the work completed through the ending date of the fellowship.

  3. Adaptive optics real time processing design for the advanced technology solar telescope

    NASA Astrophysics Data System (ADS)

    Richards, Kit

    2012-07-01

    The four meter Advanced Technology Solar Telescope (ATST) adaptive optics (AO) system will require at least twenty-four times the real time processing power as the Dunn Solar Telescope AO system. An FPGA solution for ATST AO real time processing is being pursued instead of the parallel DSP approach used for the Dunn AO76 system. An analysis shows FPGAs will have lower latency and lower hardware cost than an equivalent DSP solution. Interfacing to the proposed high speed camera and the deformable mirror will be simpler and have lower latency than with DSPs. This paper will discuss the current design and progress toward implementing the FPGA solution.

  4. Real-time Periodic Processing of RT-middleware Utilizing Linux Standard Functionalities

    NASA Astrophysics Data System (ADS)

    Shimizu, Masaharu; Toda, Kengo; Hayashibara, Yasuo; Yamato, Hideaki; Furuta, Takayuki

    A new methodology of real-time periodic processing on RT-middleware based on the Linux standard functionalities is presented in this paper. The central of discussion is on the realization of real-time processing while keeping the reusability of software modules ensured by the RT-middleware framework as well as the portability provided by the Linux development mainstream. In order to show the validity of the proposed approach, two robot systems, including an omnidirectional electric wheelchair steered by haptic joystick, are presented and the discussion about the evaluation result follows from the view point of practicality.

  5. Using Multiple FPGA Architectures for Real-time Processing of Low-level Machine Vision Functions

    Treesearch

    Thomas H. Drayer; William E. King; Philip A. Araman; Joseph G. Tront; Richard W. Conners

    1995-01-01

    In this paper, we investigate the use of multiple Field Programmable Gate Array (FPGA) architectures for real-time machine vision processing. The use of FPGAs for low-level processing represents an excellent tradeoff between software and special purpose hardware implementations. A library of modules that implement common low-level machine vision operations is presented...

  6. Real-time processing of interferograms for monitoring protein crystal growth on the Space Station

    NASA Technical Reports Server (NTRS)

    Choudry, A.; Dupuis, N.

    1988-01-01

    The possibility of using microscopic interferometric techniques to monitor the growth of protein crystals on the Space Station is studied. Digital image processing techniques are used to develop a system for the real-time analysis of microscopic interferograms of nucleation sites during protein crystal growth. Features of the optical setup and the image processing system are discussed and experimental results are presented.

  7. Real-time processing of interferograms for monitoring protein crystal growth on the Space Station

    NASA Technical Reports Server (NTRS)

    Choudry, A.; Dupuis, N.

    1988-01-01

    The possibility of using microscopic interferometric techniques to monitor the growth of protein crystals on the Space Station is studied. Digital image processing techniques are used to develop a system for the real-time analysis of microscopic interferograms of nucleation sites during protein crystal growth. Features of the optical setup and the image processing system are discussed and experimental results are presented.

  8. Closed Loop Requirements and Analysis Management

    NASA Technical Reports Server (NTRS)

    Lamoreaux, Michael; Verhoef, Brett

    2015-01-01

    Effective systems engineering involves the use of analysis in the derivation of requirements and verification of designs against those requirements. The initial development of requirements often depends on analysis for the technical definition of specific aspects of a product. Following the allocation of system-level requirements to a product's components, the closure of those requirements often involves analytical approaches to verify that the requirement criteria have been satisfied. Meanwhile, changes that occur in between these two processes need to be managed in order to achieve a closed-loop requirement derivation/verification process. Herein are presented concepts for employing emerging Team center capabilities to jointly manage requirements and analysis data such that analytical techniques are utilized to effectively derive and allocate requirements, analyses are consulted and updated during the change evaluation processes, and analyses are leveraged during the design verification process. Recommendations on concept validation case studies are also discussed.

  9. Improved process control through real-time measurement of mineral content

    SciTech Connect

    Turler, Daniel; Karaca, Murat; Davis, William B.; Giauque, Robert D.; Hopkins, Deborah

    2001-11-02

    In a highly collaborative research and development project with mining and university partners, sensors and data-analysis tools are being developed for rock-mass characterization and real-time measurement of mineral content. Determining mineralogy prior to mucking in an open-pit mine is important for routing the material to the appropriate processing stream. A possible alternative to lab assay of dust and cuttings obtained from drill holes is continuous on-line sampling and real-time x-ray fluorescence (XRF) spectroscopy. Results presented demonstrate that statistical analyses combined with XRF data can be employed to identify minerals and, possibly, different rock types. The objective is to create a detailed three-dimensional mineralogical map in real time that would improve downstream process efficiency.

  10. Real-time liquid-crystal atmosphere turbulence simulator with graphic processing unit.

    PubMed

    Hu, Lifa; Xuan, Li; Li, Dayu; Cao, Zhaoliang; Mu, Quanquan; Liu, Yonggang; Peng, Zenghui; Lu, Xinghai

    2009-04-27

    To generate time-evolving atmosphere turbulence in real time, a phase-generating method for our liquid-crystal (LC) atmosphere turbulence simulator (ATS) is derived based on the Fourier series (FS) method. A real matrix expression for generating turbulence phases is given and calculated with a graphic processing unit (GPU), the GeForce 8800 Ultra. A liquid crystal on silicon (LCOS) with 256x256 pixels is used as the turbulence simulator. The total time to generate a turbulence phase is about 7.8 ms for calculation and readout with the GPU. A parallel processing method of calculating and sending a picture to the LCOS is used to improve the simulating speed of our LC ATS. Therefore, the real-time turbulence phase-generation frequency of our LC ATS is up to 128 Hz. To our knowledge, it is the highest speed used to generate a turbulence phase in real time.

  11. Real-time digital holographic microscopy using the graphic processing unit.

    PubMed

    Shimobaba, Tomoyoshi; Sato, Yoshikuni; Miura, Junya; Takenouchi, Mai; Ito, Tomoyoshi

    2008-08-04

    Digital holographic microscopy (DHM) is a well-known powerful method allowing both the amplitude and phase of a specimen to be simultaneously observed. In order to obtain a reconstructed image from a hologram, numerous calculations for the Fresnel diffraction are required. The Fresnel diffraction can be accelerated by the FFT (Fast Fourier Transform) algorithm. However, real-time reconstruction from a hologram is difficult even if we use a recent central processing unit (CPU) to calculate the Fresnel diffraction by the FFT algorithm. In this paper, we describe a real-time DHM system using a graphic processing unit (GPU) with many stream processors, which allows use as a highly parallel processor. The computational speed of the Fresnel diffraction using the GPU is faster than that of recent CPUs. The real-time DHM system can obtain reconstructed images from holograms whose size is 512 x 512 grids in 24 frames per second.

  12. Real-time multi-camera video acquisition and processing platform for ADAS

    NASA Astrophysics Data System (ADS)

    Saponara, Sergio

    2016-04-01

    The paper presents the design of a real-time and low-cost embedded system for image acquisition and processing in Advanced Driver Assisted Systems (ADAS). The system adopts a multi-camera architecture to provide a panoramic view of the objects surrounding the vehicle. Fish-eye lenses are used to achieve a large Field of View (FOV). Since they introduce radial distortion of the images projected on the sensors, a real-time algorithm for their correction is also implemented in a pre-processor. An FPGA-based hardware implementation, re-using IP macrocells for several ADAS algorithms, allows for real-time processing of input streams from VGA automotive CMOS cameras.

  13. Process for fabricating device structures for real-time process control of silicon doping

    DOEpatents

    Weiner, Kurt H.

    2001-01-01

    Silicon device structures designed to allow measurement of important doping process parameters immediately after the doping step has occurred. The test structures are processed through contact formation using standard semiconductor fabrication techniques. After the contacts have been formed, the structures are covered by an oxide layer and an aluminum layer. The aluminum layer is then patterned to expose the contact pads and selected regions of the silicon to be doped. Doping is then performed, and the whole structure is annealed with a pulsed excimer laser. But laser annealing, unlike standard annealing techniques, does not effect the aluminum contacts because the laser light is reflected by the aluminum. Once the annealing process is complete, the structures can be probed, using standard techniques, to ascertain data about the doping step. Analysis of the data can be used to determine probable yield reductions due to improper execution of the doping step and thus provide real-time feedback during integrated circuit fabrication.

  14. Custom FPGA processing for real-time fetal ECG extraction and identification.

    PubMed

    Torti, E; Koliopoulos, D; Matraxia, M; Danese, G; Leporati, F

    2017-01-01

    Monitoring the fetal cardiac activity during pregnancy is of crucial importance for evaluating fetus health. However, there is a lack of automatic and reliable methods for Fetal ECG (FECG) monitoring that can perform this elaboration in real-time. In this paper, we present a hardware architecture, implemented on the Altera Stratix V FPGA, capable of separating the FECG from the maternal ECG and to correctly identify it. We evaluated our system using both synthetic and real tracks acquired from patients beyond the 20th pregnancy week. This work is part of a project aiming at developing a portable system for FECG continuous real-time monitoring. Its characteristics of reduced power consumption, real-time processing capability and reduced size make it suitable to be embedded in the overall system, that is the first proposed exploiting Blind Source Separation with this technology, to the best of our knowledge.

  15. Organizing the Extremely Large LSST Database forReal-Time Astronomical Processing

    SciTech Connect

    Becla, Jacek; Lim, Kian-Tat; Monkewitz, Serge; Nieto-Santisteban, Maria; Thakar, Ani; /Johns Hopkins U.

    2007-11-07

    The Large Synoptic Survey Telescope (LSST) will catalog billions of astronomical objects and trillions of sources, all of which will be stored and managed by a database management system. One of the main challenges is real-time alert generation. To generate alerts, up to 100K new difference detections have to be cross-correlated with the huge historical catalogs, and then further processed to prune false alerts. This paper explains the challenges, the implementation of the LSST Association Pipeline and the database organization strategies we are planning to use to meet the real-time requirements, including data partitioning, parallelization, and pre-loading.

  16. Real time 3D structural and Doppler OCT imaging on graphics processing units

    NASA Astrophysics Data System (ADS)

    Sylwestrzak, Marcin; Szlag, Daniel; Szkulmowski, Maciej; Gorczyńska, Iwona; Bukowska, Danuta; Wojtkowski, Maciej; Targowski, Piotr

    2013-03-01

    In this report the application of graphics processing unit (GPU) programming for real-time 3D Fourier domain Optical Coherence Tomography (FdOCT) imaging with implementation of Doppler algorithms for visualization of the flows in capillary vessels is presented. Generally, the time of the data processing of the FdOCT data on the main processor of the computer (CPU) constitute a main limitation for real-time imaging. Employing additional algorithms, such as Doppler OCT analysis, makes this processing even more time consuming. Lately developed GPUs, which offers a very high computational power, give a solution to this problem. Taking advantages of them for massively parallel data processing, allow for real-time imaging in FdOCT. The presented software for structural and Doppler OCT allow for the whole processing with visualization of 2D data consisting of 2000 A-scans generated from 2048 pixels spectra with frame rate about 120 fps. The 3D imaging in the same mode of the volume data build of 220 × 100 A-scans is performed at a rate of about 8 frames per second. In this paper a software architecture, organization of the threads and optimization applied is shown. For illustration the screen shots recorded during real time imaging of the phantom (homogeneous water solution of Intralipid in glass capillary) and the human eye in-vivo is presented.

  17. External Tank CIL Closed Loop Verification System

    NASA Technical Reports Server (NTRS)

    Hartley, Eugene A., Jr.

    2005-01-01

    Lockheed Martin was requested to develop a closed loop CIL system following the Challenger accident. The system that was developed has proven to be very robust with minimal problems since implementation, having zero escapes in the last 7 years (27 External Tanks). We are currently investigating expansion of the CIL Closed Loop system to include "MI" CILs.

  18. In-Situ Real Time Monitoring and Control of Mold Making and Filling Processes

    SciTech Connect

    2004-11-01

    This factsheet describes a research effort to develop an innovative approach to introduce technologies for real-time characterization of sand molds, lost foam patterns, and monitoring of the mold filling process. This will reduce scrap, improve product quality, and save energy.

  19. Perception and Presupposition in Real-Time Language Comprehension: Insights from Anticipatory Processing

    ERIC Educational Resources Information Center

    Chambers, Craig G.; San Juan, Valerie

    2008-01-01

    Recent studies have shown that listeners use verbs and other predicate terms to anticipate reference to semantic entities during real-time language comprehension. This process involves evaluating the denoted action against relevant properties of potential referents. The current study explored whether action-relevant properties are readily…

  20. Real-time image processing for rapid contaminant detection on broiler carcasses

    NASA Astrophysics Data System (ADS)

    Park, Bosoon; Lawrence, Kurt C.; Windham, William R.; Snead, M. Preston

    2004-11-01

    Recently, the imaging research group at Russell Research Center, ARS in Athens, Georgia has developed a real-time multispectral imaging system for fecal and ingesta contaminant detection on broiler carcasses. The prototype system includes a common aperture camera with three optical trim filters (515.4, 566.4 and 631-nm wavelength), which were selected by visible/NIR spectroscopy and validated by a hyperspectral imaging system. The preliminary results showed that the multispectral imaging technique can be used effectively for detecting feces (from duodenum, ceca, and colon) and ingesta on the surface of poultry carcasses with a processing speed of 140 birds per minute. The accuracy for the detection of fecal and ingesta contaminates was 96%. However, the system contains many false positives including scabs, feathers, and boundaries. This paper demonstrates calibration of common aperture multispectral imaging hardware and real-time multispectral image processing software. The software design, especially the Unified Modeling Language (UML) design approach was used to develop real-time image processing software for on-line application. The UML models including class, object, activity, sequence, and collaboration diagram were discussed. Both hardware and software for a real-time fecal and ingesta contaminant detection were tested at the pilot-scale poultry processing line.

  1. Real-Time and Post-Processed Orbit Determination and Positioning

    NASA Technical Reports Server (NTRS)

    Bar-Sever, Yoaz E. (Inventor); Bertiger, William I. (Inventor); Dorsey, Angela R. (Inventor); Harvey, Nathaniel E. (Inventor); Lu, Wenwen (Inventor); Miller, Kevin J. (Inventor); Miller, Mark A. (Inventor); Romans, Larry J. (Inventor); Sibthorpe, Anthony J. (Inventor); Weiss, Jan P. (Inventor); Garcia Fernandez, Miquel (Inventor); Gross, Jason (Inventor)

    2016-01-01

    Novel methods and systems for the accurate and efficient processing of real-time and latent global navigation satellite systems (GNSS) data are described. Such methods and systems can perform orbit determination of GNSS satellites, orbit determination of satellites carrying GNSS receivers, positioning of GNSS receivers, and environmental monitoring with GNSS data.

  2. Real-Time and Post-Processed Orbit Determination and Positioning

    NASA Technical Reports Server (NTRS)

    Bar-Sever, Yoaz E. (Inventor); Bertiger, William I. (Inventor); Dorsey, Angela R. (Inventor); Harvey, Nathaniel E. (Inventor); Lu, Wenwen (Inventor); Miller, Kevin J. (Inventor); Miller, Mark A. (Inventor); Romans, Larry J. (Inventor); Sibthorpe, Anthony J. (Inventor); Weiss, Jan P. (Inventor); Garcia Fernandez, Miquel (Inventor); Gross, Jason (Inventor)

    2015-01-01

    Novel methods and systems for the accurate and efficient processing of real-time and latent global navigation satellite systems (GNSS) data are described. Such methods and systems can perform orbit determination of GNSS satellites, orbit determination of satellites carrying GNSS receivers, positioning of GNSS receivers, and environmental monitoring with GNSS data.

  3. Multiprocessor DSP for real-time data processing on Earth orbiting scatterometers

    NASA Technical Reports Server (NTRS)

    Bachmann, A.; Clark, D.; Lux, J.; Steffke, R.

    2000-01-01

    The implementation of a Multi DSP radar signal processor for a Ku-Band Earth orbiting scatterometer is discussed. A testbed has been assembled using a combination of commercial DSP hardware and spaceflight components to evaluate the proposed multiprocessing approaches. Test results of real-time radar echo processing are presented, as well as proposed designs for future investigation.

  4. Real-Time and Memory Correlation via Acousto-Optic Processing,

    DTIC Science & Technology

    1978-06-01

    acousto - optic technology as an answer to these requirements appears very attractive. Three fundamental signal-processing schemes using the acousto ... optic interaction have been investigated: (i) real-time correlation and convolution, (ii) Fourier and discrete Fourier transformation, and (iii

  5. Multiprocessor DSP for real-time data processing on Earth orbiting scatterometers

    NASA Technical Reports Server (NTRS)

    Bachmann, A.; Clark, D.; Lux, J.; Steffke, R.

    2000-01-01

    The implementation of a Multi DSP radar signal processor for a Ku-Band Earth orbiting scatterometer is discussed. A testbed has been assembled using a combination of commercial DSP hardware and spaceflight components to evaluate the proposed multiprocessing approaches. Test results of real-time radar echo processing are presented, as well as proposed designs for future investigation.

  6. Role of Text and Student Characteristics in Real-Time Reading Processes across the Primary Grades

    ERIC Educational Resources Information Center

    de Leeuw, Linda; Segers, Eliane; Verhoeven, Ludo

    2016-01-01

    Although much is known about beginning readers using behavioural measures, real-time processes are still less clear. The present study examined eye movements (skipping rate, gaze, look back and second-pass duration) as a function of text-related (difficulty and word class) and student-related characteristics (word decoding, reading comprehension,…

  7. Role of Text and Student Characteristics in Real-Time Reading Processes across the Primary Grades

    ERIC Educational Resources Information Center

    de Leeuw, Linda; Segers, Eliane; Verhoeven, Ludo

    2016-01-01

    Although much is known about beginning readers using behavioural measures, real-time processes are still less clear. The present study examined eye movements (skipping rate, gaze, look back and second-pass duration) as a function of text-related (difficulty and word class) and student-related characteristics (word decoding, reading comprehension,…

  8. Perception and Presupposition in Real-Time Language Comprehension: Insights from Anticipatory Processing

    ERIC Educational Resources Information Center

    Chambers, Craig G.; San Juan, Valerie

    2008-01-01

    Recent studies have shown that listeners use verbs and other predicate terms to anticipate reference to semantic entities during real-time language comprehension. This process involves evaluating the denoted action against relevant properties of potential referents. The current study explored whether action-relevant properties are readily…

  9. Real-time multiuser image processing system for research and development

    NASA Astrophysics Data System (ADS)

    Andersson, Ingmar A.

    1993-01-01

    This is a description of the SAAB Missiles image processing laboratory. At present four persons can work simultaneously with advanced image processing and it is easy to expand the system. A lot of functions can be realized in real-time since it consists of 21 image processing boards. It is the combination of the extremely fast image processing and the multi-user function that makes this system unique.

  10. Closed-Loop Analysis of Soft Decisions for Serial Links

    NASA Technical Reports Server (NTRS)

    Lansdowne, Chatwin A.; Steele, Glen F.; Zucha, Joan P.; Schlesinger, Adam M.

    2013-01-01

    We describe the benefit of using closed-loop measurements for a radio receiver paired with a counterpart transmitter. We show that real-time analysis of the soft decision output of a receiver can provide rich and relevant insight far beyond the traditional hard-decision bit error rate (BER) test statistic. We describe a Soft Decision Analyzer (SDA) implementation for closed-loop measurements on single- or dual- (orthogonal) channel serial data communication links. The analyzer has been used to identify, quantify, and prioritize contributors to implementation loss in live-time during the development of software defined radios. This test technique gains importance as modern receivers are providing soft decision symbol synchronization as radio links are challenged to push more data and more protocol overhead through noisier channels, and software-defined radios (SDRs) use error-correction codes that approach Shannon's theoretical limit of performance.

  11. Closed loop deep brain stimulation: an evolving technology.

    PubMed

    Hosain, Md Kamal; Kouzani, Abbas; Tye, Susannah

    2014-12-01

    Deep brain stimulation is an effective and safe medical treatment for a variety of neurological and psychiatric disorders including Parkinson's disease, essential tremor, dystonia, and treatment resistant obsessive compulsive disorder. A closed loop deep brain stimulation (CLDBS) system automatically adjusts stimulation parameters by the brain response in real time. The CLDBS continues to evolve due to the advancement in the brain stimulation technologies. This paper provides a study on the existing systems developed for CLDBS. It highlights the issues associated with CLDBS systems including feedback signal recording and processing, stimulation parameters setting, control algorithm, wireless telemetry, size, and power consumption. The benefits and limitations of the existing CLDBS systems are also presented. Whilst robust clinical proof of the benefits of the technology remains to be achieved, it has the potential to offer several advantages over open loop DBS. The CLDBS can improve efficiency and efficacy of therapy, eliminate lengthy start-up period for programming and adjustment, provide a personalized treatment, and make parameters setting automatic and adaptive.

  12. Laser airborne remote sensing real-time acquisition, processing, and control system

    NASA Astrophysics Data System (ADS)

    Kelly, Brian T.; Pierson, Robert E.; Dropka, T. J.; Dowling, James A.; Lang, L. M.; Fox, Marsha J.

    1997-10-01

    The US Air Force Phillips Laboratory is evaluating the feasibility of long-standoff-range remote sensing of gaseous species present in trace amounts in the atmosphere. Extensive system integration in the laboratory and an airborne test are leading to remote sensing ground test and airborne missions within the next year. This paper describes the design, external interfaces. and initial performance of the Laser Airborne Remote Sensing acquisition, processing, and control system to be deployed on the Phillips Laboratory NC-135 research aircraft for differential absorption lidar system performance tests. The dual-CPU VME-based real-time computer system synchronizes experiment timing and pulsed CO2 laser operation up to 30 Hz while controlling optical subsystem components such as a laser grating, receiver gain, mirror alignment, and laser shutters. This real-time system acquires high rate detector signals from the outgoing and return laser pulses as well as a low rate health and status signals form the optical bench and the aircraft. Laser pulse and status data are processed and displayed in real time on one of four graphical user interfaces: one devoted to system control, one to remote mirror alignment, and two other interfaces for real-time data analysis and diagnostics. The dual-CPU and multi- layered software decouple time critical and non-critical tasks allowing great flexibility in flight-time display and processing.

  13. Closed-loop approach to thermodynamics

    NASA Astrophysics Data System (ADS)

    Goupil, C.; Ouerdane, H.; Herbert, E.; Benenti, G.; D'Angelo, Y.; Lecoeur, Ph.

    2016-09-01

    We present the closed-loop approach to linear nonequilibrium thermodynamics considering a generic heat engine dissipatively connected to two temperature baths. The system is usually quite generally characterized by two parameters: the output power P and the conversion efficiency η , to which we add a third one, the working frequency ω . We establish that a detailed understanding of the effects of the dissipative coupling on the energy conversion process requires only knowing two quantities: the system's feedback factor β and its open-loop gain A0, which product A0β characterizes the interplay between the efficiency, the output power, and the operating rate of the system. By raising the abstract hermodynamic analysis to a higher level, the feedback loop approach provides a versatile and economical, hence fairly efficient, tool for the study of any conversion engine operation for which a feedback factor can be defined.

  14. Real Time Coincidence Processing Algorithm for Geiger Mode LADAR using FPGAs

    DTIC Science & Technology

    2017-01-09

    processing algorithm implemented on a FPGA . By utilizing FPGAs we are able to achieve a “micro-ladar” system that resides in a design space not...developed embedded FPGA real time processing algorithms that take noisy raw data, streaming at upwards of 1GB/sec, and filters the data to obtain a near- ly...current operating parameters and extrapo- lated for future system upgrades. Simulated ladar data is processed using the FPGA and compared to the Matlab

  15. Experimental optimization of a real time fed-batch fermentation process using Markov decision process.

    PubMed

    Saucedo, V M; Karim, M N

    1997-07-20

    This article describes a methodology that implements a Markov decision process (MDP) optimization technique in a real time fed-batch experiment. Biological systems can be better modeled under the stochastic framework and MDP is shown to be a suitable technique for their optimization. A nonlinear input/output model is used to calculate the probability transitions. All elements of the MDP are identified according to physical parameters. Finally, this study compares the results obtained when optimizing ethanol production using the infinite horizon problem, with total expected discount policy, to previous experimental results aimed at optimizing ethanol production using a recombinant Escherichia coli fed-batch cultivation. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 55: 317-327, 1997.

  16. A computational approach to real-time image processing for serial time-encoded amplified microscopy

    NASA Astrophysics Data System (ADS)

    Oikawa, Minoru; Hiyama, Daisuke; Hirayama, Ryuji; Hasegawa, Satoki; Endo, Yutaka; Sugie, Takahisa; Tsumura, Norimichi; Kuroshima, Mai; Maki, Masanori; Okada, Genki; Lei, Cheng; Ozeki, Yasuyuki; Goda, Keisuke; Shimobaba, Tomoyoshi

    2016-03-01

    High-speed imaging is an indispensable technique, particularly for identifying or analyzing fast-moving objects. The serial time-encoded amplified microscopy (STEAM) technique was proposed to enable us to capture images with a frame rate 1,000 times faster than using conventional methods such as CCD (charge-coupled device) cameras. The application of this high-speed STEAM imaging technique to a real-time system, such as flow cytometry for a cell-sorting system, requires successively processing a large number of captured images with high throughput in real time. We are now developing a high-speed flow cytometer system including a STEAM camera. In this paper, we describe our approach to processing these large amounts of image data in real time. We use an analog-to-digital converter that has up to 7.0G samples/s and 8-bit resolution for capturing the output voltage signal that involves grayscale images from the STEAM camera. Therefore the direct data output from the STEAM camera generates 7.0G byte/s continuously. We provided a field-programmable gate array (FPGA) device as a digital signal pre-processor for image reconstruction and finding objects in a microfluidic channel with high data rates in real time. We also utilized graphics processing unit (GPU) devices for accelerating the calculation speed of identification of the reconstructed images. We built our prototype system, which including a STEAM camera, a FPGA device and a GPU device, and evaluated its performance in real-time identification of small particles (beads), as virtual biological cells, owing through a microfluidic channel.

  17. Real-time Graphics Processing Unit Based Fourier Domain Optical Coherence Tomography and Surgical Applications

    NASA Astrophysics Data System (ADS)

    Zhang, Kang

    2011-12-01

    In this dissertation, real-time Fourier domain optical coherence tomography (FD-OCT) capable of multi-dimensional micrometer-resolution imaging targeted specifically for microsurgical intervention applications was developed and studied. As a part of this work several ultra-high speed real-time FD-OCT imaging and sensing systems were proposed and developed. A real-time 4D (3D+time) OCT system platform using the graphics processing unit (GPU) to accelerate OCT signal processing, the imaging reconstruction, visualization, and volume rendering was developed. Several GPU based algorithms such as non-uniform fast Fourier transform (NUFFT), numerical dispersion compensation, and multi-GPU implementation were developed to improve the impulse response, SNR roll-off and stability of the system. Full-range complex-conjugate-free FD-OCT was also implemented on the GPU architecture to achieve doubled image range and improved SNR. These technologies overcome the imaging reconstruction and visualization bottlenecks widely exist in current ultra-high speed FD-OCT systems and open the way to interventional OCT imaging for applications in guided microsurgery. A hand-held common-path optical coherence tomography (CP-OCT) distance-sensor based microsurgical tool was developed and validated. Through real-time signal processing, edge detection and feed-back control, the tool was shown to be capable of track target surface and compensate motion. The micro-incision test using a phantom was performed using a CP-OCT-sensor integrated hand-held tool, which showed an incision error less than +/-5 microns, comparing to >100 microns error by free-hand incision. The CP-OCT distance sensor has also been utilized to enhance the accuracy and safety of optical nerve stimulation. Finally, several experiments were conducted to validate the system for surgical applications. One of them involved 4D OCT guided micro-manipulation using a phantom. Multiple volume renderings of one 3D data set were

  18. A distributed multiprocessor system designed for real-time image processing

    NASA Astrophysics Data System (ADS)

    Yin, Zhiyi; Heng, Wei

    2008-11-01

    In real-time image processing, a large amount of data is needed to be processed at a very high speed. Considering the problems faced in real-time image processing, a distributed multiprocessor system is proposed in this paper. In the design of the distributed multiprocessor system, processing tasks are allocated to various processes, which are bound to different CPUs. Several designs are discussed, and making full use of every process is very important to system's excellent performance. Furthermore, the problems of realization fasten on the inter-process communication, the synchronization, and the stability. System analysis and performance tests both show that the distributed multiprocessor system is able to improve system's performance variously, including the delay, the throughput rate, the stability, the scalability. And the system can be expanded easy at aspects of software and hardware. In a word, the distributed multiprocessor system designed for real-time image processing, based on distributed algorithms, not only improves system's performance variously, but also costs low and expands easy.

  19. Fast processing of quantitative phase profiles from off-axis interferograms for real-time applications

    NASA Astrophysics Data System (ADS)

    Girshovitz, Pinhas; Shaked, Natan T.

    2015-03-01

    We review new and efficient algorithms, lately presented by us, for rapid reconstruction of quantitative phase maps from off-axis digital interferograms. These algorithms improve the conventional Fourier-based algorithm by using the Fourier transforms and the phase unwrapping process more efficiently, and thus decrease the calculation complexity required for extracting the sample phase map from the recorded interferograms. Using the new algorithms, on a standard personal computer without using the graphic processing-unit programming or parallel computing, we were able to speed up the processing and reach frame rates of up to 45 frames per second for one megapixel off-axis interferograms. These capabilities allow real-time visualization, calculation and data extraction for dynamic samples and processes, inspected by off-axis digital holography. Specific applications include biological cell imaging without labeling and real-time nondestructive testing.

  20. Real-time hyperspectral image processing for UAV applications, using HySpex Mjolnir-1024

    NASA Astrophysics Data System (ADS)

    Koirala, Pesal; Løke, Trond; Baarstad, Ivar; Fridman, Andrei; Hernandez, Julio

    2017-05-01

    The HySpex Mjolnir-1024 hyperspectral camera provides a unique combination of small form factor and low mass combined with high performance and scientific grade data quality. The camera has spatial resolution of 1024 pixels, spectral resolution of 200 bands within 400 nm to 1000 nm wavelength range and F1.8 optics that ensures high light throughput. Rugged design with good thermal and mechanical stability makes Mjolnir-1024 an excellent option for a wide range of scientific applications for airborne UAV operations and field applications. The optical architecture is based on the high-end ODIN-1024 system and features a total FOV of 20 degrees with approximately 0.1 pixel residual keystone effect and even smaller residual smile effect after resampling. With a total mass of less than 4 kg including hyperspectral camera, data acquisition unit, IMU and GPS, the system is suitable for even relatively small UAVs. The system is generic and can be deployed on a wide range of UAVs with various downlink capabilities. The ground station software enables full control of the sensor settings and has the capability to show in real time the location of the UAV, plot the flight path of the UAV and display a georeferenced waterfall preview image in order to give instant feedback on spatial coverage. The system can be triggered automatically by the UAV's flight management system, but can also be controlled manually. Mjolnir-1024 housing contains both the camera hardware and a high performance onboard computer. The computer enables advanced processing capabilities such as real-time georeferencing based on the data streams from the camera and INS. The system is also capable of performing real-time image analysis such as anomaly detection, NDVI and SAM. The data products can be overlaid on top of various background maps and images in real time. The real-time processing results can also be downlinked and displayed directly on the monitor of the ground station.

  1. Evaluation of High-Rate Real Time GPS Processing at USGS Pasadena

    NASA Astrophysics Data System (ADS)

    King, N. E.; Langbein, J. O.; Lisowski, M.; Hudnut, K. W.; Stark, K.; Aspiotes, A.

    2009-12-01

    Recent advances in hardware, telemetry, and processing software make possible real-time geodetic monitoring, including monitoring of fault-crossing lifelines, increased integration of geodetic and seismic networks, and improved geodetic response to large earthquakes. USGS Pasadena operates 97 permanent continuously operating GPS stations in southern California. To further the earthquake-response mission of USGS, these stations are in heavily populated urban areas and along the southern San Andreas fault. With support from city and county land surveyors, and the USGS MultiHazards Demonstration Project, USGS Pasadena has been upgrading its stations to real-time (1 second sampling interval), and broadcasting RTCM streams, for several years. USGS Pasadena currently operates 30 stations in real time, recently co-located GPS at four new or upgraded seismic stations along the southern San Andreas fault, and anticipates upgrading many more in the next year or two. Testing of real-time processing shows that, over a time span of several days, the proportion of observations within 100 mm of the mean value is typically over 98% for the north and east components and 93% or better for the vertical component. Outliers exceeding 1 m are a small percentage (< 0.1%) of the observations, and automated algorithms will be required to reject them. Telemetry outages and the resulting baseline configuration change sometimes cause re-convergence to a different position. We expect that, with development of automated tools to handle outlier detection and configuration change, high-rate and real-time GPS results will significantly improve our capacity to monitor fault slip and respond to southern California earthquakes.

  2. Real-time SAR image processing onboard a Venus orbiting spacecraft

    NASA Technical Reports Server (NTRS)

    Arens, W. E.

    1978-01-01

    The potential use of real-time synthetic aperture radar (SAR) processing to produce 200 meter resolution imagery onboard a 1983 Venus orbiter imaging radar spacecraft is described. The VOIR SAR processing requirements are defined in terms of a nominal baseline design evolving from a 1977 VOIR mission study. A candidate onboard SAR processor architecture compatible with the VOIR requirements is next detailed. Finally, implementation characteristics, based upon currently available integrated circuits, are estimated in terms of chip count, power, and weight.

  3. Federated Stream Processing Support for Real-Time Business Intelligence Applications

    NASA Astrophysics Data System (ADS)

    Botan, Irina; Cho, Younggoo; Derakhshan, Roozbeh; Dindar, Nihal; Haas, Laura; Kim, Kihong; Tatbul, Nesime

    In this paper, we describe the MaxStream federated stream processing architecture to support real-time business intelligence applications. MaxStream builds on and extends the SAP MaxDB relational database system in order to provide a federator over multiple underlying stream processing engines and databases. We show preliminary results on usefulness and performance of the MaxStream architecture on the SAP Sales and Distribution Benchmark.

  4. Direct analysis in real time mass spectrometry, a process analytical technology tool for real-time process monitoring in botanical drug manufacturing.

    PubMed

    Wang, Lu; Zeng, Shanshan; Chen, Teng; Qu, Haibin

    2014-03-01

    A promising process analytical technology (PAT) tool has been introduced for batch processes monitoring. Direct analysis in real time mass spectrometry (DART-MS), a means of rapid fingerprint analysis, was applied to a percolation process with multi-constituent substances for an anti-cancer botanical preparation. Fifteen batches were carried out, including ten normal operations and five abnormal batches with artificial variations. The obtained multivariate data were analyzed by a multi-way partial least squares (MPLS) model. Control trajectories were derived from eight normal batches, and the qualification was tested by R(2) and Q(2). Accuracy and diagnosis capability of the batch model were then validated by the remaining batches. Assisted with high performance liquid chromatography (HPLC) determination, process faults were explained by corresponding variable contributions. Furthermore, a batch level model was developed to compare and assess the model performance. The present study has demonstrated that DART-MS is very promising in process monitoring in botanical manufacturing. Compared with general PAT tools, DART-MS offers a particular account on effective compositions and can be potentially used to improve batch quality and process consistency of samples in complex matrices.

  5. Real-time image edge enhancement with a spiral phase filter and graphic processing unit.

    PubMed

    Zhong, Zhi; Gao, Pengjun; Shan, Mingguang; Wang, Ying; Zhang, Yabin

    2014-07-01

    Isotropic image edge enhancement with high contrast can be achieved using a spiral phase filter (SPF) in a 4f optical system. However, real-time application of edge enhancement with SPF has generally been limited due to the requirement of coherent light or complex phase-shifting operation. In this paper, we demonstrate a real-time image edge enhancement method using a SPF and a graphic processing unit (GPU). By implementing the process of virtual spiral phase filtering on GPU, we are able to speed up the whole procedure by more than 8.3× with respect to CPU processing, and ultimately achieve video rate for megapixel images. In particular, our implementation can achieve higher speedup for more multiple images. These developments are increasing the potential for image edge enhancement of moving objects.

  6. Applying an integrated neuro-expert system model in a real-time alarm processing system

    NASA Astrophysics Data System (ADS)

    Khosla, Rajiv; Dillon, Tharam S.

    1993-03-01

    In this paper we propose an integrated model which is derived from the combination of a generic neuro-expert system model, an object model, and unix operating system process (UOSP) model. This integrated model reflects the strengths of both artificial neural nets (ANNs) and expert systems (ESs). A formalism of ES object, ANN object, UOSP object, and problem domain object is used for developing a set of generic data structures and methods. These generic data structures and methods help us to build heterogeneous ES-ANN objects with uniform communication interface. The integrated model is applied in a real-time alarm processing system for a non-trivial terminal power station. It is shown how features like hierarchical/distributed ES/ANN objects, inter process communication, and fast concurrent execution help to cope with real-time system constraints like, continuity, data variability, and fast response time.

  7. Quantification of DNA fragmentation in processed foods using real-time PCR.

    PubMed

    Mano, Junichi; Nishitsuji, Yasuyuki; Kikuchi, Yosuke; Fukudome, Shin-Ichi; Hayashida, Takuya; Kawakami, Hiroyuki; Kurimoto, Youichi; Noguchi, Akio; Kondo, Kazunari; Teshima, Reiko; Takabatake, Reona; Kitta, Kazumi

    2017-07-01

    DNA analysis of processed foods is performed widely to detect various targets, such as genetically modified organisms (GMOs). Food processing often causes DNA fragmentation, which consequently affects the results of PCR analysis. In order to assess the effects of DNA fragmentation on the reliability of PCR analysis, we investigated a novel methodology to quantify the degree of DNA fragmentation. We designed four real-time PCR assays that amplified 18S ribosomal RNA gene sequences common to various plants at lengths of approximately 100, 200, 400, and 800 base pairs (bp). Then, we created an indicator value, "DNA fragmentation index (DFI)", which is calculated from the Cq values derived from the real-time PCR assays. Finally, we demonstrated the efficacy of this method for the quality control of GMO detection in processed foods by evaluating the relationship between the DFI and the limit of detection.

  8. Real-time control of electron density in a capacitively coupled plasma

    SciTech Connect

    Keville, Bernard; Gaman, Cezar; Turner, Miles M.; Zhang Yang; Daniels, Stephen; Holohan, Anthony M.

    2013-05-15

    Reactive ion etching (RIE) is sensitive to changes in chamber conditions, such as wall seasoning, which have a deleterious effect on process reproducibility. The application of real time, closed loop control to RIE may reduce this sensitivity and facilitate production with tighter tolerances. The real-time, closed loop control of plasma density with RF power in a capacitively coupled argon plasma using a hairpin resonance probe as a sensor is described. Elementary control analysis shows that an integral controller provides stable and effective set point tracking and disturbance attenuation. The trade off between performance and robustness may be quantified in terms of one parameter, namely the position of the closed loop pole. Experimental results are presented, which are consistent with the theoretical analysis.

  9. Real-time processing of radar return on a parallel computer

    NASA Technical Reports Server (NTRS)

    Aalfs, David D.

    1992-01-01

    NASA is working with the FAA to demonstrate the feasibility of pulse Doppler radar as a candidate airborne sensor to detect low altitude windshears. The need to provide the pilot with timely information about possible hazards has motivated a demand for real-time processing of a radar return. Investigated here is parallel processing as a means of accommodating the high data rates required. A PC based parallel computer, called the transputer, is used to investigate issues in real time concurrent processing of radar signals. A transputer network is made up of an array of single instruction stream processors that can be networked in a variety of ways. They are easily reconfigured and software development is largely independent of the particular network topology. The performance of the transputer is evaluated in light of the computational requirements. A number of algorithms have been implemented on the transputers in OCCAM, a language specially designed for parallel processing. These include signal processing algorithms such as the Fast Fourier Transform (FFT), pulse-pair, and autoregressive modelling, as well as routing software to support concurrency. The most computationally intensive task is estimating the spectrum. Two approaches have been taken on this problem, the first and most conventional of which is to use the FFT. By using table look-ups for the basis function and other optimizing techniques, an algorithm has been developed that is sufficient for real time. The other approach is to model the signal as an autoregressive process and estimate the spectrum based on the model coefficients. This technique is attractive because it does not suffer from the spectral leakage problem inherent in the FFT. Benchmark tests indicate that autoregressive modeling is feasible in real time.

  10. A flexible software architecture for scalable real-time image and video processing applications

    NASA Astrophysics Data System (ADS)

    Usamentiaga, Rubén; Molleda, Julio; García, Daniel F.; Bulnes, Francisco G.

    2012-06-01

    Real-time image and video processing applications require skilled architects, and recent trends in the hardware platform make the design and implementation of these applications increasingly complex. Many frameworks and libraries have been proposed or commercialized to simplify the design and tuning of real-time image processing applications. However, they tend to lack flexibility because they are normally oriented towards particular types of applications, or they impose specific data processing models such as the pipeline. Other issues include large memory footprints, difficulty for reuse and inefficient execution on multicore processors. This paper presents a novel software architecture for real-time image and video processing applications which addresses these issues. The architecture is divided into three layers: the platform abstraction layer, the messaging layer, and the application layer. The platform abstraction layer provides a high level application programming interface for the rest of the architecture. The messaging layer provides a message passing interface based on a dynamic publish/subscribe pattern. A topic-based filtering in which messages are published to topics is used to route the messages from the publishers to the subscribers interested in a particular type of messages. The application layer provides a repository for reusable application modules designed for real-time image and video processing applications. These modules, which include acquisition, visualization, communication, user interface and data processing modules, take advantage of the power of other well-known libraries such as OpenCV, Intel IPP, or CUDA. Finally, we present different prototypes and applications to show the possibilities of the proposed architecture.

  11. Closed-Loop System Removes Contaminants From Inert Gas

    NASA Technical Reports Server (NTRS)

    Sharma, Pramod K.

    1995-01-01

    Concentration of oxygen in this closed-loop system kept low by use of heated catalytic sorbent bed in cartridge. Proposed to keep concentration of water vapor low by use of predried zeolite sorbent bed in another cartridge, and to remove particles smaller than 0.1 micrometer by use of porous metal filters. In specific application, chamber is one in which semiconducting materials processed. By virtue of closed-loop operation, limited supply of inert gas adequate to provide atmosphere for industrial processing of semiconductors.

  12. Deep architecture neural network-based real-time image processing for image-guided radiotherapy.

    PubMed

    Mori, Shinichiro

    2017-08-01

    To develop real-time image processing for image-guided radiotherapy, we evaluated several neural network models for use with different imaging modalities, including X-ray fluoroscopic image denoising. Setup images of prostate cancer patients were acquired with two oblique X-ray fluoroscopic units. Two types of residual network were designed: a convolutional autoencoder (rCAE) and a convolutional neural network (rCNN). We changed the convolutional kernel size and number of convolutional layers for both networks, and the number of pooling and upsampling layers for rCAE. The ground-truth image was applied to the contrast-limited adaptive histogram equalization (CLAHE) method of image processing. Network models were trained to keep the quality of the output image close to that of the ground-truth image from the input image without image processing. For image denoising evaluation, noisy input images were used for the training. More than 6 convolutional layers with convolutional kernels >5×5 improved image quality. However, this did not allow real-time imaging. After applying a pair of pooling and upsampling layers to both networks, rCAEs with >3 convolutions each and rCNNs with >12 convolutions with a pair of pooling and upsampling layers achieved real-time processing at 30 frames per second (fps) with acceptable image quality. Use of our suggested network achieved real-time image processing for contrast enhancement and image denoising by the use of a conventional modern personal computer. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  13. A standard curve based method for relative real time PCR data processing

    PubMed Central

    Larionov, Alexey; Krause, Andreas; Miller, William

    2005-01-01

    Background Currently real time PCR is the most precise method by which to measure gene expression. The method generates a large amount of raw numerical data and processing may notably influence final results. The data processing is based either on standard curves or on PCR efficiency assessment. At the moment, the PCR efficiency approach is preferred in relative PCR whilst the standard curve is often used for absolute PCR. However, there are no barriers to employ standard curves for relative PCR. This article provides an implementation of the standard curve method and discusses its advantages and limitations in relative real time PCR. Results We designed a procedure for data processing in relative real time PCR. The procedure completely avoids PCR efficiency assessment, minimizes operator involvement and provides a statistical assessment of intra-assay variation. The procedure includes the following steps. (I) Noise is filtered from raw fluorescence readings by smoothing, baseline subtraction and amplitude normalization. (II) The optimal threshold is selected automatically from regression parameters of the standard curve. (III) Crossing points (CPs) are derived directly from coordinates of points where the threshold line crosses fluorescence plots obtained after the noise filtering. (IV) The means and their variances are calculated for CPs in PCR replicas. (V) The final results are derived from the CPs' means. The CPs' variances are traced to results by the law of error propagation. A detailed description and analysis of this data processing is provided. The limitations associated with the use of parametric statistical methods and amplitude normalization are specifically analyzed and found fit to the routine laboratory practice. Different options are discussed for aggregation of data obtained from multiple reference genes. Conclusion A standard curve based procedure for PCR data processing has been compiled and validated. It illustrates that standard curve design

  14. Near-real-time simulations of biolelectric activity in small mammalian hearts using graphical processing units.

    PubMed

    Vigmond, Edward J; Boyle, Patrick M; Leon, L; Plank, Gernot

    2009-01-01

    Simulations of cardiac bioelectric phenomena remain a significant challenge despite continual advancements in computational machinery. Spanning large temporal and spatial ranges demands millions of nodes to accurately depict geometry, and a comparable number of timesteps to capture dynamics. This study explores a new hardware computing paradigm, the graphics processing unit (GPU), to accelerate cardiac models, and analyzes results in the context of simulating a small mammalian heart in real time. The ODEs associated with membrane ionic flow were computed on traditional CPU and compared to GPU performance, for one to four parallel processing units. The scalability of solving the PDE responsible for tissue coupling was examined on a cluster using up to 128 cores. Results indicate that the GPU implementation was between 9 and 17 times faster than the CPU implementation and scaled similarly. Solving the PDE was still 160 times slower than real time.

  15. Real-time monitoring of DNA hybridization and melting processes using a fiber optic sensor.

    PubMed

    Delport, Filip; Pollet, Jeroen; Janssen, Kris; Verbruggen, Bert; Knez, Karel; Spasic, Dragana; Lammertyn, Jeroen

    2012-02-17

    In this paper a fiber optic surface plasmon resonance (FO-SPR) sensor was used to analyze the melting process of DNA linked to silica nanoparticles. Real-time monitoring of a DNA melting process has rarely been studied using surface plasmon resonance (SPR), since most commercial SPR setups do not allow for dynamic and accurate temperature control above 50 °C. The FO-SPR sensor platform, with silica nanobead signal amplification, allows sensing inside a standard PCR thermocycler, which makes high resolution DNA melting curve analysis possible. This innovative combination was used to characterize the hybridization and melting events between DNA immobilized on the sensor surface and DNA probes on silica nanoparticles. At optimized hybridization conditions complementary DNA strands of different lengths could be distinguished. While the real-time FO-SPR analysis of DNA hybridization did not result in significant variances, the analysis of DNA melting determined the exact length of overlap and the matching Gibbs energy.

  16. A frequency diversity process for speckle reduction in real-time ultrasonic images.

    PubMed

    Galloway, R L; McDermott, B A; Thurstone, F L

    1988-01-01

    A pair of concurrent real-time B-mode image lines has been formed using a parallel processing system. In this system a wideband received echo is partitioned by a frequency diversity process and separate image lines are formed. Due to their differing constituent frequencies, these image lines have decorrelated speckle patterns. Upon averaging these filtered lines, the amount of speckle in the resultant displayed image is reduced. The reduction in image speckle and its accompanying improvement in perceived resolution is accomplished with no sacrifice of temporal resolution or real-time format. The effects of filter separation and filter quality factor (Q) are investigated through statistical analysis of images containing speckle-producing targets. A measurable improvement in image signal-to-noise ratio has been achieved.

  17. US GEOLOGICAL SURVEY'S NATIONAL SYSTEM FOR PROCESSING AND DISTRIBUTION OF NEAR REAL-TIME HYDROLOGICAL DATA.

    USGS Publications Warehouse

    Shope, William G.; ,

    1987-01-01

    The US Geological Survey is utilizing a national network of more than 1000 satellite data-collection stations, four satellite-relay direct-readout ground stations, and more than 50 computers linked together in a private telecommunications network to acquire, process, and distribute hydrological data in near real-time. The four Survey offices operating a satellite direct-readout ground station provide near real-time hydrological data to computers located in other Survey offices through the Survey's Distributed Information System. The computerized distribution system permits automated data processing and distribution to be carried out in a timely manner under the control and operation of the Survey office responsible for the data-collection stations and for the dissemination of hydrological information to the water-data users.

  18. Real time polarization sensor image processing on an embedded FPGA/multi-core DSP system

    NASA Astrophysics Data System (ADS)

    Bednara, Marcus; Chuchacz-Kowalczyk, Katarzyna

    2015-05-01

    Most embedded image processing SoCs available on the market are highly optimized for typical consumer applications like video encoding/decoding, motion estimation or several image enhancement processes as used in DSLR or digital video cameras. For non-consumer applications, on the other hand, optimized embedded hardware is rarely available, so often PC based image processing systems are used. We show how a real time capable image processing system for a non-consumer application - namely polarization image data processing - can be efficiently implemented on an FPGA and multi-core DSP based embedded hardware platform.

  19. A High Speed Mobile Courier Data Access System That Processes Database Queries in Real-Time

    NASA Astrophysics Data System (ADS)

    Gatsheni, Barnabas Ndlovu; Mabizela, Zwelakhe

    A secure high-speed query processing mobile courier data access (MCDA) system for a Courier Company has been developed. This system uses the wireless networks in combination with wired networks for updating a live database at the courier centre in real-time by an offsite worker (the Courier). The system is protected by VPN based on IPsec. There is no system that we know of to date that performs the task for the courier as proposed in this paper.

  20. A portable real-time data processing system for standard meteorological radiosondes

    NASA Technical Reports Server (NTRS)

    Staffanson, F. L.

    1983-01-01

    The UMET-1 is a microprocessor-based portable system for automatic real-time processing of flight data transmitted from the standard RAWINSONDE upper atmosphere meteorological balloonsonde. The first 'target system' is described which was designed to receive data from a mobile tracking and telemetry receiving station (TRADAT), as the balloonsonde ascends to apogee. After balloon-burst, the UMET-1 produces user-ready hardcopy.

  1. Closed-loop performance of pyramid wavefront sensor

    NASA Astrophysics Data System (ADS)

    Esposito, Simone; Riccardi, Armando; Feeney, Orla

    2000-07-01

    We consider the performance of the wavefront reconstruction process when a Pyramid wavefront Sensor is used in a closed loop Adaptive Optics System. The Pyramid Sensor sensitivity in closed loop operations has been the subject of a first heuristic analysis showing that the sensor sensitivity is higher than that of a Shack-Hartmann sensor, at least when low order modes are considered. In this paper we evaluate the sensor accuracy by determining the closed loop reconstruction matrix. This is done using a diffractive analysis of the sensor behavior. Furthermore, knowledge of this matrix enables us to quantify the effect of error sources like sensor non linearity and photon noise on the reconstructed wavefront accuracy. Finally, a comparison of the performance of the Shack-Hartmann and Pyramid wavefront sensors is given.

  2. Iterative LQG Controller Design Through Closed-Loop Identification

    NASA Technical Reports Server (NTRS)

    Hsiao, Min-Hung; Huang, Jen-Kuang; Cox, David E.

    1996-01-01

    This paper presents an iterative Linear Quadratic Gaussian (LQG) controller design approach for a linear stochastic system with an uncertain open-loop model and unknown noise statistics. This approach consists of closed-loop identification and controller redesign cycles. In each cycle, the closed-loop identification method is used to identify an open-loop model and a steady-state Kalman filter gain from closed-loop input/output test data obtained by using a feedback LQG controller designed from the previous cycle. Then the identified open-loop model is used to redesign the state feedback. The state feedback and the identified Kalman filter gain are used to form an updated LQC controller for the next cycle. This iterative process continues until the updated controller converges. The proposed controller design is demonstrated by numerical simulations and experiments on a highly unstable large-gap magnetic suspension system.

  3. A Cloud-Based Infrastructure for Near-Real-Time Processing and Dissemination of NPP Data

    NASA Astrophysics Data System (ADS)

    Evans, J. D.; Valente, E. G.; Chettri, S. S.

    2011-12-01

    We are building a scalable cloud-based infrastructure for generating and disseminating near-real-time data products from a variety of geospatial and meteorological data sources, including the new National Polar-Orbiting Environmental Satellite System (NPOESS) Preparatory Project (NPP). Our approach relies on linking Direct Broadcast and other data streams to a suite of scientific algorithms coordinated by NASA's International Polar-Orbiter Processing Package (IPOPP). The resulting data products are directly accessible to a wide variety of end-user applications, via industry-standard protocols such as OGC Web Services, Unidata Local Data Manager, or OPeNDAP, using open source software components. The processing chain employs on-demand computing resources from Amazon.com's Elastic Compute Cloud and NASA's Nebula cloud services. Our current prototype targets short-term weather forecasting, in collaboration with NASA's Short-term Prediction Research and Transition (SPoRT) program and the National Weather Service. Direct Broadcast is especially crucial for NPP, whose current ground segment is unlikely to deliver data quickly enough for short-term weather forecasters and other near-real-time users. Direct Broadcast also allows full local control over data handling, from the receiving antenna to end-user applications: this provides opportunities to streamline processes for data ingest, processing, and dissemination, and thus to make interpreted data products (Environmental Data Records) available to practitioners within minutes of data capture at the sensor. Cloud computing lets us grow and shrink computing resources to meet large and rapid fluctuations in data availability (twice daily for polar orbiters) - and similarly large fluctuations in demand from our target (near-real-time) users. This offers a compelling business case for cloud computing: the processing or dissemination systems can grow arbitrarily large to sustain near-real time data access despite surges in

  4. Comparison of Different Techniques for Processing GNSS Data in Real Time for Tsunami Warning

    NASA Astrophysics Data System (ADS)

    Schmidt, M.; Dragert, H.; Lu, Y.; Henton, J.; MacLeod, K.

    2012-12-01

    Real-time processing and dissemination of GNSS derived co-seismic position offsets for tsunami early warning has been under development at the Geological Survey of Canada (NRCan) for the past six years. Using streamed data from the Western Canada Deformation Array (WCDA), results from two variations of Precise Point Positioning (PPP) and two variations of network-based solutions are evaluated: NRCan's real-time PPP software, and two commercial software packages RTD and RTNET, licensed from Geodetics Inc. and GPS Solutions Inc. respectively. Of the two commercial packages, the former provides independent, epoch-by-epoch network solutions, while the latter has the capability to process data using both PPP and Network approaches. There are clear advantages and disadvantages to the independent PPP solutions vs. the network based solutions. PPP solutions (smoothed and un-smoothed) provide position estimates for single stations in a global framework. They are not reliant on 'fixed' reference stations that, if located within the seismogenic zone, will clearly experience co-seismic displacements. Under best-case scenarios, error levels of 1-2 cm horizontal and 3-6cm vertical are achievable for network based solutions whereas PPP solutions with ambiguity resolution are currently somewhat noisier. Both analysis methodologies are critically dependent on data continuity and robust tracking of all available satellites at each site. A clear case is made for the requirement for network based processing capacity for baselines of greater than 150km in order to ensure robust co-seismic displacement estimates during large earthquakes. Results from tests within the WCDA network using the different techniques are presented as well as recommendations for computational and operational improvements. NRCan's real-time web based interface offers the user community with a real-time display of position offset estimates for sites in southwestern coastal British Columbia.

  5. Real-time image processing and control interface for remote operation of a microscope

    NASA Astrophysics Data System (ADS)

    Leng, Hesong; Wilder, Joseph

    1999-08-01

    A real-time image processing and control interface for remote operation of a microscope is presented in this paper. The system has achieved real-time color image display for 640 X 480 pixel images. Multi-resolution image representation can be provided for efficient transmission through the network. Through the control interface the computer can communicate with the programmable microscope via the RS232 serial ports. By choosing one of three scanning patterns, a sequence of images can be saved as BMP or PGM files to record information on an entire microscope slide. The system will be used by medical and graduate students at the University of Medicine and Dentistry of New Jersey for distance learning. It can be used in many network-based telepathology applications.

  6. Note: A high count rate real-time digital processing method for PGNAA data acquisition system.

    PubMed

    Liu, Yuzhe; Chen, Lian; Li, Feng; Liang, Futian; Jin, Ge

    2017-07-01

    The prompt gamma neutron activation analysis (PGNAA) technique is a real-time online method to analyze the composition of industrial materials. This paper presents a data acquisition system with a high count rate and real-time digital processing method for PGNAA. Limited by the decay time of the detector, the ORTEC multi-channel analyzer (MCA) can normally achieve an average count rate of 100 kcps. However, this system uses an electrical technique to increase the average count rate and reduce dead time, and guarantees good accuracy. Since the measuring time is usually limited to about 120 s, in order to accelerate the accumulation rate of spectrum and reduce the statistical error, the average count rate is expected to reach more than 500 kcps.

  7. Demonstration plan for real time receiving and processing of flight data from the space transportation system

    NASA Technical Reports Server (NTRS)

    Russell, James W.; Avery, Don E.

    1993-01-01

    This report presents a detailed demonstration test plan for receiving and processing data from experiments being conducted on the Space Transportation System near real time at the NASA Langley Research Center (LaRC). This task can readily be achieved using the Orbital Acceleration Research Experiment (OARE). The Space Shuttle data flow is described including both the payload and the mission data. A description is presented of the OARE instrument which is used to measure low frequency Space Shuttle accelerations in nano-gs. Procedures are shown for obtaining the required mission data and OARE payload data at LaRC. The demonstration test plan schedule and costs are presented. It is recommended that both the OARE data and the pertinent Space Shuttle mission data be received at LaRC over the NASA Communication System (NASCOM) on a near real time basis.

  8. Real-time spatiotemporal division multiplexing electroholography with a single graphics processing unit utilizing movie features.

    PubMed

    Niwase, Hiroaki; Takada, Naoki; Araki, Hiromitsu; Nakayama, Hirotaka; Sugiyama, Atsushi; Kakue, Takashi; Shimobaba, Tomoyoshi; Ito, Tomoyoshi

    2014-11-17

    We propose a real-time spatiotemporal division multiplexing electroholography utilizing the features of movies. The proposed method spatially divides a 3-D object into plural parts and periodically selects a divided part in each frame, thereby reconstructing a three-dimensional (3-D) movie of the original object. Computer-generated holograms of the selected part are calculated by a single graphics processing unit and sequentially displayed on a spatial light modulator. Visual continuity enables a reconstructed movie of the original 3-D object. The proposed method realized a real-time reconstructed movie of a 3-D object composed of 11,646 points at over 30 frames per second (fps). We also displayed a reconstructed movie of a 3-D object composed of 44,647 points at about 10 fps.

  9. Note: A high count rate real-time digital processing method for PGNAA data acquisition system

    NASA Astrophysics Data System (ADS)

    Liu, Yuzhe; Chen, Lian; Li, Feng; Liang, Futian; Jin, Ge

    2017-07-01

    The prompt gamma neutron activation analysis (PGNAA) technique is a real-time online method to analyze the composition of industrial materials. This paper presents a data acquisition system with a high count rate and real-time digital processing method for PGNAA. Limited by the decay time of the detector, the ORTEC multi-channel analyzer (MCA) can normally achieve an average count rate of 100 kcps. However, this system uses an electrical technique to increase the average count rate and reduce dead time, and guarantees good accuracy. Since the measuring time is usually limited to about 120 s, in order to accelerate the accumulation rate of spectrum and reduce the statistical error, the average count rate is expected to reach more than 500 kcps.

  10. Just noticeable difference level estimation in real-time digital signal processing

    NASA Astrophysics Data System (ADS)

    Piotrowski, Zbigniew; Rudkowski, Wojciech

    2008-01-01

    Modern state-of-the art watermarking systems use precise algorithms for ensure perceptual transparency of the additional signal in the host signal presence. Various Human Auditory System (HAS) models are implemented but only few of them are computationally effective giving reliable acoustic masking effect. This paper presents efficient algorithm and its implementation for Just Noticeable Difference level estimation using HAS for data hiding application. Implementation is based on effective Johnston [1] HAS model and real-time processing using TMS 320C6713 DSK board. The results of implementation as well as subjective fidelity test using standard ITU-R BS 1116.1 are described and illustrated. Numerical results of DSP real-time implementation are compared with the Matlab off-line HAS computational model.

  11. Real-time lossy compression of hyperspectral images using iterative error analysis on graphics processing units

    NASA Astrophysics Data System (ADS)

    Sánchez, Sergio; Plaza, Antonio

    2012-06-01

    Hyperspectral image compression is an important task in remotely sensed Earth Observation as the dimensionality of this kind of image data is ever increasing. This requires on-board compression in order to optimize the donwlink connection when sending the data to Earth. A successful algorithm to perform lossy compression of remotely sensed hyperspectral data is the iterative error analysis (IEA) algorithm, which applies an iterative process which allows controlling the amount of information loss and compression ratio depending on the number of iterations. This algorithm, which is based on spectral unmixing concepts, can be computationally expensive for hyperspectral images with high dimensionality. In this paper, we develop a new parallel implementation of the IEA algorithm for hyperspectral image compression on graphics processing units (GPUs). The proposed implementation is tested on several different GPUs from NVidia, and is shown to exhibit real-time performance in the analysis of an Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS) data sets collected over different locations. The proposed algorithm and its parallel GPU implementation represent a significant advance towards real-time onboard (lossy) compression of hyperspectral data where the quality of the compression can be also adjusted in real-time.

  12. A complete solar eruption activity processing tool with robotization and real time (II)

    NASA Astrophysics Data System (ADS)

    Lin, Ganghua; Zhao, Cui; Yang, Xiao

    2014-07-01

    Intense solar active events have made significant impacts on the modern high technology system and living environment of human being, therefore solar activities forecast and space weather forecast are getting more and more attention. Meanwhile, data volume acquisitioned by solar monitor facility is growing larger and larger due to the requirement of multiple dimensions observation and high temporal and spatial resolution. As staffs of a solar monitor data producer, we are encouraged to adopt new techniques and methods to provide valuable information to solar activities forecast organization and the other related users, and provide convenient products and tools to the users. In the previous paper "A complete solar eruption activities processing tool with robotization and real time (I)", we presented a fully automatic and real time detecting architecture for different solar erupt activities. In this paper, we present new components of new data sets in the architecture design, latest progresses on automatic recognition of solar flare, filament and magnetic field, and a newly introduced method with which solar photospheric magnetic nonpotentiality parameters are processed in real time, then its result directly can be used in solar active forecast.

  13. Language at three timescales: The role of real-time processes in language development and evolution

    PubMed Central

    McMurray, Bob

    2016-01-01

    Evolutionary developmental systems (Evo-Devo) theory stresses that selection pressures operate on entire developmental systems rather than just genes. This paper extends this approach to language evolution arguing that selection pressure may operate on two quasi-independent timescales. First, children clearly must acquire language successfully (as acknowledged in traditional Evo-Devo accounts) and evolution must equip them with the tools to do so. Second, while this is developing they must also communicate with others in the moment using partially developed knowledge. These pressures may require different solutions and their combination may underlie the evolution of complex mechanisms for language development and processing. I present two case studies to illustrate how the demands of both real-time communication and language acquisition may be subtly different (and interact). The first case study examines infant directed speech (IDS). A recent view is that IDS underwent cultural to statistical learning mechanisms that infants use to acquire the speech categories of their language. However, recent data suggest is it may not have evolved to enhance development, but rather to serve a more real-time communicative function. The second case study examines the argument for seemingly specialized mechanisms for learning word meanings (e.g., fast-mapping). Both behavioral and computational work suggest that learning may be much slower, and served by general purpose mechanisms like associative learning. Fast-mapping, then, may be a real-time process meant to serve immediate communication, not learning, by augmenting incomplete vocabulary knowledge with constraints from the current context. Together, these studies suggest that evolutionary accounts consider selection pressure arising from both real-time communicative demands and from the need for accurate language development. PMID:26991438

  14. Language at Three Timescales: The Role of Real-Time Processes in Language Development and Evolution.

    PubMed

    McMurray, Bob

    2016-04-01

    Evolutionary developmental systems (evo-devo) theory stresses that selection pressures operate on entire developmental systems rather than just genes. This study extends this approach to language evolution, arguing that selection pressure may operate on two quasi-independent timescales. First, children clearly must acquire language successfully (as acknowledged in traditional evo-devo accounts) and evolution must equip them with the tools to do so. Second, while this is developing, they must also communicate with others in the moment using partially developed knowledge. These pressures may require different solutions, and their combination may underlie the evolution of complex mechanisms for language development and processing. I present two case studies to illustrate how the demands of both real-time communication and language acquisition may be subtly different (and interact). The first case study examines infant-directed speech (IDS). A recent view is that IDS underwent cultural to statistical learning mechanisms that infants use to acquire the speech categories of their language. However, recent data suggest is it may not have evolved to enhance development, but rather to serve a more real-time communicative function. The second case study examines the argument for seemingly specialized mechanisms for learning word meanings (e.g., fast-mapping). Both behavioral and computational work suggest that learning may be much slower and served by general-purpose mechanisms like associative learning. Fast-mapping, then, may be a real-time process meant to serve immediate communication, not learning, by augmenting incomplete vocabulary knowledge with constraints from the current context. Together, these studies suggest that evolutionary accounts consider selection pressure arising from both real-time communicative demands and from the need for accurate language development. Copyright © 2016 Cognitive Science Society, Inc.

  15. Neural network feature detector for real-time video signal processing.

    PubMed

    Naylor, D; Jones, S; Myers, D; Vincent, J

    1993-12-01

    The application of artificial neural networks to real-time image processing tasks requires the use of dedicated, high performance hardware. A linear array processor called HANNIBAL has been developed which implements the backpropagation neural learning algorithm on-chip. This paper considers the design of a complete neural system which integrates HANNIBAL into an existing image processing environment. The goals for the design of the system have been set partly by the primary application, namely feature recognition, but mainly by the desire for a flexible, high performance hardware tool for the study and evaluation of range of neural image processing applications.

  16. A closed-loop dual-modulation multi-spectral polarimeter for glucose monitoring

    NASA Astrophysics Data System (ADS)

    Yu, Zhen fang; Pirnstill, Casey W.; Coté, Gerard L.

    2016-03-01

    Optical polarimetry is a promising noninvasive means of assessing glucose concentration in the aqueous humor of the eye. One the major limiting factors is time-varying cornea birefringence due to motion artifact, which prevents the realization of this device. In this study, we simultaneously utilize laser intensity modulation and Faraday polarization rotation modulation for a real-time closed-loop multi-spectral polarimeter for glucose monitoring in vitro. In this report, a real-time closed-loop dual-modulation dual-spectral polarimeter was presented and in vitro glucose measurements were performed demonstrating the accuracy and repeatability of this polarimeter.

  17. A wearable smartphone-based platform for real-time cardiovascular disease detection via electrocardiogram processing.

    PubMed

    Oresko, Joseph J; Duschl, Heather; Cheng, Allen C

    2010-05-01

    Cardiovascular disease (CVD) is the single leading cause of global mortality and is projected to remain so. Cardiac arrhythmia is a very common type of CVD and may indicate an increased risk of stroke or sudden cardiac death. The ECG is the most widely adopted clinical tool to diagnose and assess the risk of arrhythmia. ECGs measure and display the electrical activity of the heart from the body surface. During patients' hospital visits, however, arrhythmias may not be detected on standard resting ECG machines, since the condition may not be present at that moment in time. While Holter-based portable monitoring solutions offer 24-48 h ECG recording, they lack the capability of providing any real-time feedback for the thousands of heart beats they record, which must be tediously analyzed offline. In this paper, we seek to unite the portability of Holter monitors and the real-time processing capability of state-of-the-art resting ECG machines to provide an assistive diagnosis solution using smartphones. Specifically, we developed two smartphone-based wearable CVD-detection platforms capable of performing real-time ECG acquisition and display, feature extraction, and beat classification. Furthermore, the same statistical summaries available on resting ECG machines are provided.

  18. Graphic processing unit accelerated real-time partially coherent beam generator

    NASA Astrophysics Data System (ADS)

    Ni, Xiaolong; Liu, Zhi; Chen, Chunyi; Jiang, Huilin; Fang, Hanhan; Song, Lujun; Zhang, Su

    2016-07-01

    A method of using liquid-crystals (LCs) to generate a partially coherent beam in real-time is described. An expression for generating a partially coherent beam is given and calculated using a graphic processing unit (GPU), i.e., the GeForce GTX 680. A liquid-crystal on silicon (LCOS) with 256 × 256 pixels is used as the partially coherent beam generator (PCBG). An optimizing method with partition convolution is used to improve the generating speed of our LC PCBG. The total time needed to generate a random phase map with a coherence width range from 0.015 mm to 1.5 mm is less than 2.4 ms for calculation and readout with the GPU; adding the time needed for the CPU to read and send to LCOS with the response time of the LC PCBG, the real-time partially coherent beam (PCB) generation frequency of our LC PCBG is up to 312 Hz. To our knowledge, it is the first real-time partially coherent beam generator. A series of experiments based on double pinhole interference are performed. The result shows that to generate a laser beam with a coherence width of 0.9 mm and 1.5 mm, with a mean error of approximately 1%, the RMS values needed 0.021306 and 0.020883 and the PV values required 0.073576 and 0.072998, respectively.

  19. Real-Time Joint Streaming Data Processing from Social and Physical Sensors

    NASA Astrophysics Data System (ADS)

    Kropivnitskaya, Y. Y.; Qin, J.; Tiampo, K. F.; Bauer, M.

    2014-12-01

    The results of the technological breakthroughs in computing that have taken place over the last few decades makes it possible to achieve emergency management objectives that focus on saving human lives and decreasing economic effects. In particular, the integration of a wide variety of information sources, including observations from spatially-referenced physical sensors and new social media sources, enables better real-time seismic hazard analysis through distributed computing networks. The main goal of this work is to utilize innovative computational algorithms for better real-time seismic risk analysis by integrating different data sources and processing tools into streaming and cloud computing applications. The Geological Survey of Canada operates the Canadian National Seismograph Network (CNSN) with over 100 high-gain instruments and 60 low-gain or strong motion seismographs. The processing of the continuous data streams from each station of the CNSN provides the opportunity to detect possible earthquakes in near real-time. The information from physical sources is combined to calculate a location and magnitude for an earthquake. The automatically calculated results are not always sufficiently precise and prompt that can significantly reduce the response time to a felt or damaging earthquake. Social sensors, here represented as Twitter users, can provide information earlier to the general public and more rapidly to the emergency planning and disaster relief agencies. We introduce joint streaming data processing from social and physical sensors in real-time based on the idea that social media observations serve as proxies for physical sensors. By using the streams of data in the form of Twitter messages, each of which has an associated time and location, we can extract information related to a target event and perform enhanced analysis by combining it with physical sensor data. Results of this work suggest that the use of data from social media, in conjunction

  20. In-Situ Real Time Monitoring and Control of Mold Making and Filling Processes: Final Report

    SciTech Connect

    Mohamed Abdelrahman; Kenneth Currie

    2010-12-22

    This project presents a model for addressing several objectives envisioned by the metal casting industries through the integration of research and educational components. It provides an innovative approach to introduce technologies for real time characterization of sand molds, lost foam patterns and monitoring of the mold filling process. The technology developed will enable better control over the casting process. It is expected to reduce scrap and variance in the casting quality. A strong educational component is integrated into the research plan to utilize increased awareness of the industry professional, the potential benefits of the developed technology, and the potential benefits of cross cutting technologies.

  1. Acousto-Optic Interaction in Surface Acoustic Waves and Its Application to Real Time Signal Processing.

    DTIC Science & Technology

    1977-12-30

    ACOUSTO - OPTIC INTERACTION IN SURFACE ACOUSTIC WAVES AND ITS APP--ETC(U) DEC 77 0 SCHUMER, P DAS NOOOIJ -75-C-0772 NCLASSIFIED MA-ONR-30 Nt.EE E’h...CHART NAT*NAL BUREAU OF STANDARDS 1-63- ACOUSTO - OPTIC INTERACTION IN SURFACE ACOUSTIC WAVES AND ITS APPLICATION TO REAL TIME SIGNAL PROCESSING By 00 D... Acousto - optics , Integrated optics, Optical Signal Processing. 20. AbSKTRACT (Continue an reverse side it neceary and idewnt& by block mum ber) The

  2. Real-Time FPGA Processing for High-Speed Optical Frequency Domain Imaging

    PubMed Central

    Vakoc, Benjamin J.; Suter, Melissa J.; Yun, Seok-Hyun; Tearney, Guillermo J.; Bouma, Brett E.

    2010-01-01

    We present a novel algorithm for reconstructing interferograms acquired in optical frequency domain imaging (OFDI). The algorithm was developed specifically for processing in field programmable gate arrays (FPGAs) and featured the use of a finite-impulse-response (FIR) filter implementation of B-spline interpolation for efficiently re-sampling k-space. When implemented in FPGAs, the algorithm allowed for real-time processing of interferograms acquired with a high-speed OFDI system at 54 kHz and a sampling rate of 100 MS/s. PMID:19336296

  3. Observations of breakup processes of liquid jets using real-time X-ray radiography

    NASA Technical Reports Server (NTRS)

    Char, J. M.; Kuo, K. K.; Hsieh, K. C.

    1988-01-01

    To unravel the liquid-jet breakup process in the nondilute region, a newly developed system of real-time X-ray radiography, an advanced digital image processor, and a high-speed video camera were used. Based upon recorded X-ray images, the inner structure of a liquid jet during breakup was observed. The jet divergence angle, jet breakup length, and fraction distributions along the axial and transverse directions of the liquid jets were determined in the near-injector region. Both wall- and free-jet tests were conducted to study the effect of wall friction on the jet breakup process.

  4. Real Time Signal Processing and Data Handling with dedicated hardware in handheld OCT Device

    NASA Astrophysics Data System (ADS)

    Guerra, P.; Valverde, J. J.; Martin, A.; Ledesma, M. J.; Rubio-Guivernau, J. L.; Santos, A.

    2015-11-01

    The manuscript presents the topics on real time signal processing with dedicated hardware presented at the INFIERI Summer School 2014. The focus of this work is on real-time signal processing, filtering and massive parallel computing. In general, medical devices have stringed demands on energy consumption as well as on data processing and handling. In fact, the development of novel medical devices has led to significant advances in fields such as instrumentation, algorithm development and image processing. In this manuscript, two aspects of the design are brought into consideration: the transformation of a conventional signal processing algorithm into an equivalent version that is suitable for hardware implementation and the use of on-chip modules originally developed for mass-electronics applications, for high speed data transmission. The development of a novel state-of-the-art hand-held OCT probe is used to exemplify theses aspects. In particular, the ``design process'' behind the implementation of a multichannel quadrature coherent demodulator is disclosed.

  5. Closed-loop neurostimulation: the clinical experience.

    PubMed

    Sun, Felice T; Morrell, Martha J

    2014-07-01

    Neurostimulation is now an established therapy for the treatment of movement disorders, pain, and epilepsy. While most neurostimulation systems available today provide stimulation in an open-loop manner (i.e., therapy is delivered according to preprogrammed settings and is unaffected by changes in the patient's clinical symptoms or in the underlying disease), closed-loop neurostimulation systems, which modulate or adapt therapy in response to physiological changes, may provide more effective and efficient therapy. At present, few such systems exist owing to the complexities of designing and implementing implantable closed-loop systems. This review focuses on the clinical experience of four implantable closed-loop neurostimulation systems: positional-adaptive spinal cord stimulation for treatment of pain, responsive cortical stimulation for treatment of epilepsy, closed-loop vagus nerve stimulation for treatment of epilepsy, and concurrent sensing and stimulation for treatment of Parkinson disease. The history that led to the development of the closed-loop systems, the sensing, detection, and stimulation technology that closes the loop, and the clinical experiences are presented.

  6. A real time quality control application for animal production by image processing.

    PubMed

    Sungur, Cemil; Özkan, Halil

    2015-11-01

    Standards of hygiene and health are of major importance in food production, and quality control has become obligatory in this field. Thanks to rapidly developing technologies, it is now possible for automatic and safe quality control of food production. For this purpose, image-processing-based quality control systems used in industrial applications are being employed to analyze the quality of food products. In this study, quality control of chicken (Gallus domesticus) eggs was achieved using a real time image-processing technique. In order to execute the quality control processes, a conveying mechanism was used. Eggs passing on a conveyor belt were continuously photographed in real time by cameras located above the belt. The images obtained were processed by various methods and techniques. Using digital instrumentation, the volume of the eggs was measured, broken/cracked eggs were separated and dirty eggs were determined. In accordance with international standards for classifying the quality of eggs, the class of separated eggs was determined through a fuzzy implication model. According to tests carried out on thousands of eggs, a quality control process with an accuracy of 98% was possible. © 2014 Society of Chemical Industry.

  7. Real-time processing for Fourier domain optical coherence tomography using a field programmable gate array

    NASA Astrophysics Data System (ADS)

    Ustun, Teoman E.; Iftimia, Nicusor V.; Ferguson, R. Daniel; Hammer, Daniel X.

    2008-11-01

    Real-time display of processed Fourier domain optical coherence tomography (FDOCT) images is important for applications that require instant feedback of image information, for example, systems developed for rapid screening or image-guided surgery. However, the computational requirements for high-speed FDOCT image processing usually exceeds the capabilities of most computers and therefore display rates rarely match acquisition rates for most devices. We have designed and developed an image processing system, including hardware based upon a field programmable gated array, firmware, and software that enables real-time display of processed images at rapid line rates. The system was designed to be extremely flexible and inserted in-line between any FDOCT detector and any Camera Link frame grabber. Two versions were developed for spectrometer-based and swept source-based FDOCT systems, the latter having an additional custom high-speed digitizer on the front end but using all the capabilities and features of the former. The system was tested in humans and monkeys using an adaptive optics retinal imager, in zebrafish using a dual-beam Doppler instrument, and in human tissue using a swept source microscope. A display frame rate of 27 fps for fully processed FDOCT images (1024 axial pixels×512 lateral A-scans) was achieved in the spectrometer-based systems.

  8. VerifEYE: a real-time meat inspection system for the beef processing industry

    NASA Astrophysics Data System (ADS)

    Kocak, Donna M.; Caimi, Frank M.; Flick, Rick L.; Elharti, Abdelmoula

    2003-02-01

    Described is a real-time meat inspection system developed for the beef processing industry by eMerge Interactive. Designed to detect and localize trace amounts of contamination on cattle carcasses in the packing process, the system affords the beef industry an accurate, high speed, passive optical method of inspection. Using a method patented by United States Department of Agriculture and Iowa State University, the system takes advantage of fluorescing chlorophyll found in the animal's diet and therefore the digestive track to allow detection and imaging of contaminated areas that may harbor potentially dangerous microbial pathogens. Featuring real-time image processing and documentation of performance, the system can be easily integrated into a processing facility's Hazard Analysis and Critical Control Point quality assurance program. This paper describes the VerifEYE carcass inspection and removal verification system. Results indicating the feasibility of the method, as well as field data collected using a prototype system during four university trials conducted in 2001 are presented. Two successful demonstrations using the prototype system were held at a major U.S. meat processing facility in early 2002.

  9. Real-time processing for Fourier domain optical coherence tomography using a field programmable gate array

    PubMed Central

    Ustun, Teoman E.; Iftimia, Nicusor V.; Ferguson, R. Daniel; Hammer, Daniel X.

    2008-01-01

    Real-time display of processed Fourier domain optical coherence tomography (FDOCT) images is important for applications that require instant feedback of image information, for example, systems developed for rapid screening or image-guided surgery. However, the computational requirements for high-speed FDOCT image processing usually exceeds the capabilities of most computers and therefore display rates rarely match acquisition rates for most devices. We have designed and developed an image processing system, including hardware based upon a field programmable gated array, firmware, and software that enables real-time display of processed images at rapid line rates. The system was designed to be extremely flexible and inserted in-line between any FDOCT detector and any Camera Link frame grabber. Two versions were developed for spectrometer-based and swept source-based FDOCT systems, the latter having an additional custom high-speed digitizer on the front end but using all the capabilities and features of the former. The system was tested in humans and monkeys using an adaptive optics retinal imager, in zebrafish using a dual-beam Doppler instrument, and in human tissue using a swept source microscope. A display frame rate of 27 fps for fully processed FDOCT images (1024 axial pixels×512 lateral A-scans) was achieved in the spectrometer-based systems. PMID:19045902

  10. The new Athens center on data processing from the neutron monitor network in real time

    NASA Astrophysics Data System (ADS)

    Mavromichalaki, H.; Souvatzoglou, G.; Sarlanis, C.; Mariatos, G.; Gerontidou, M.; Papaioannou, A.; Plainaki, C.; Tatsis, S.; Belov, A.; Eroshenko, E.; Yanke, V.

    2005-11-01

    The ground-based neutron monitors (NMs) record galactic and solar relativistic cosmic rays which can play a useful key role in space weather forecasting, as a result of their interaction with interplanetary disturbances. The Earth's-based neutron monitor network has been used in order to produce a real-time prediction of space weather phenomena. Therefore, the Athens Neutron Monitor Data Processing Center (ANMODAP) takes advantage of this unique multi-directional device to solve problems concerning the diagnosis and forecasting of space weather. At this moment there has been a multi-sided use of neutron monitors. On the one hand, a preliminary alert for ground level enhancements (GLEs) may be provided due to relativistic solar particles and can be registered around 20 to 30 min before the arrival of the main part of lower energy particles responsible for radiation hazard. To make a more reliable prognosis of these events, real time data from channels of lower energy particles and X-ray intensity from the GOES satellite are involved in the analysis. The other possibility is to search in real time for predictors of geomagnetic storms when they occur simultaneously with Forbush effects, using hourly, on-line accessible neutron monitor data from the worldwide network and applying a special method of processing. This chance of prognosis is only being elaborated and considered here as one of the possible uses of the Neutron Monitor Network for forecasting the arrival of interplanetary disturbance to the Earth. The achievements, the processes and the future results, are discussed in this work.

  11. Ultrasonic Real-Time Quality Monitoring Of Aluminum Spot Weld Process

    NASA Astrophysics Data System (ADS)

    Perez Regalado, Waldo Josue

    The real-time ultrasonic spot weld monitoring system, introduced by our research group, has been designed for the unsupervised quality characterization of the spot welding process. It comprises the ultrasonic transducer (probe) built into one of the welding electrodes and an electronics hardware unit which gathers information from the transducer, performs real-time weld quality characterization and communicates with the robot programmable logic controller (PLC). The system has been fully developed for the inspection of spot welds manufactured in steel alloys, and has been mainly applied in the automotive industry. In recent years, a variety of materials have been introduced to the automotive industry. These include high strength steels, magnesium alloys, and aluminum alloys. Aluminum alloys have been of particular interest due to their high strength-to-weight ratio. Resistance spot welding requirements for aluminum vary greatly from those of steel. Additionally, the oxide film formed on the aluminum surface increases the heat generation between the copper electrodes and the aluminum plates leading to accelerated electrode deterioration. Preliminary studies showed that the real-time quality inspection system was not able to monitor spot welds manufactured with aluminum. The extensive experimental research, finite element modelling of the aluminum welding process and finite difference modeling of the acoustic wave propagation through the aluminum spot welds presented in this dissertation, revealed that the thermodynamics and hence the acoustic wave propagation through an aluminum and a steel spot weld differ significantly. For this reason, the hardware requirements and the algorithms developed to determine the welds quality from the ultrasonic data used on steel, no longer apply on aluminum spot welds. After updating the system and designing the required algorithms, parameters such as liquid nugget penetration and nugget diameter were available in the ultrasonic data

  12. A Real-Time Spectroscopic Sensor for Monitoring Laser Welding Processes

    PubMed Central

    Sibillano, Teresa; Ancona, Antonio; Berardi, Vincenzo; Lugarà, Pietro Mario

    2009-01-01

    In this paper we report on the development of a sensor for real time monitoring of laser welding processes based on spectroscopic techniques. The system is based on the acquisition of the optical spectra emitted from the laser generated plasma plume and their use to implement an on-line algorithm for both the calculation of the plasma electron temperature and the analysis of the correlations between selected spectral lines. The sensor has been patented and it is currently available on the market. PMID:22412317

  13. Enhancing Sensitivity of a Miniature Spectrometer Using a Real-Time Image Processing Algorithm.

    PubMed

    Chandramohan, Sabarish; Avrutsky, Ivan

    2016-05-01

    A real-time image processing algorithm is developed to enhance the sensitivity of a planar single-mode waveguide miniature spectrometer with integrated waveguide gratings. A novel approach of averaging along the arcs in a curved coordinate system is introduced which allows for collecting more light, thereby enhancing the sensitivity. The algorithm is tested using CdSeS/ZnS quantum dots drop casted on the surface of a single-mode waveguide. Measurements indicate that a monolayer of quantum dots is expected to produce guided mode attenuation approximately 11 times above the noise level.

  14. Real-time speckle variance swept-source optical coherence tomography using a graphics processing unit

    PubMed Central

    Lee, Kenneth K. C.; Mariampillai, Adrian; Yu, Joe X. Z.; Cadotte, David W.; Wilson, Brian C.; Standish, Beau A.; Yang, Victor X. D.

    2012-01-01

    Abstract: Advances in swept source laser technology continues to increase the imaging speed of swept-source optical coherence tomography (SS-OCT) systems. These fast imaging speeds are ideal for microvascular detection schemes, such as speckle variance (SV), where interframe motion can cause severe imaging artifacts and loss of vascular contrast. However, full utilization of the laser scan speed has been hindered by the computationally intensive signal processing required by SS-OCT and SV calculations. Using a commercial graphics processing unit that has been optimized for parallel data processing, we report a complete high-speed SS-OCT platform capable of real-time data acquisition, processing, display, and saving at 108,000 lines per second. Subpixel image registration of structural images was performed in real-time prior to SV calculations in order to reduce decorrelation from stationary structures induced by the bulk tissue motion. The viability of the system was successfully demonstrated in a high bulk tissue motion scenario of human fingernail root imaging where SV images (512 × 512 pixels, n = 4) were displayed at 54 frames per second. PMID:22808428

  15. Real-time blood flow visualization using the graphics processing unit.

    PubMed

    Yang, Owen; Cuccia, David; Choi, Bernard

    2011-01-01

    Laser speckle imaging (LSI) is a technique in which coherent light incident on a surface produces a reflected speckle pattern that is related to the underlying movement of optical scatterers, such as red blood cells, indicating blood flow. Image-processing algorithms can be applied to produce speckle flow index (SFI) maps of relative blood flow. We present a novel algorithm that employs the NVIDIA Compute Unified Device Architecture (CUDA) platform to perform laser speckle image processing on the graphics processing unit. Software written in C was integrated with CUDA and integrated into a LabVIEW Virtual Instrument (VI) that is interfaced with a monochrome CCD camera able to acquire high-resolution raw speckle images at nearly 10 fps. With the CUDA code integrated into the LabVIEW VI, the processing and display of SFI images were performed also at ∼10 fps. We present three video examples depicting real-time flow imaging during a reactive hyperemia maneuver, with fluid flow through an in vitro phantom, and a demonstration of real-time LSI during laser surgery of a port wine stain birthmark.

  16. Real-time blood flow visualization using the graphics processing unit

    NASA Astrophysics Data System (ADS)

    Yang, Owen; Cuccia, David; Choi, Bernard

    2011-01-01

    Laser speckle imaging (LSI) is a technique in which coherent light incident on a surface produces a reflected speckle pattern that is related to the underlying movement of optical scatterers, such as red blood cells, indicating blood flow. Image-processing algorithms can be applied to produce speckle flow index (SFI) maps of relative blood flow. We present a novel algorithm that employs the NVIDIA Compute Unified Device Architecture (CUDA) platform to perform laser speckle image processing on the graphics processing unit. Software written in C was integrated with CUDA and integrated into a LabVIEW Virtual Instrument (VI) that is interfaced with a monochrome CCD camera able to acquire high-resolution raw speckle images at nearly 10 fps. With the CUDA code integrated into the LabVIEW VI, the processing and display of SFI images were performed also at ~10 fps. We present three video examples depicting real-time flow imaging during a reactive hyperemia maneuver, with fluid flow through an in vitro phantom, and a demonstration of real-time LSI during laser surgery of a port wine stain birthmark.

  17. CLOSED-LOOP STRIPPING ANALYSIS (CLSA) OF ...

    EPA Pesticide Factsheets

    Synthetic musk compounds are used as inexpensive fragrance materials for the production of perfumes and as additives to soap, detergent, and shampoo. They have been found in surface water, fish tissues, and human breast milk. The ubiquity of this class of compounds in the environment is attributable to high use and release into the environment. Current techniques for separating these compounds from fish tissues require tedious sample clean-up procedures. To obtain fat-free extracts, gel permeation chromatography (GPC), column chromatography using alumina, and silica gel, and thin layer chromatography (TLC clean-up procedures are frequently employed. Despite the considerable effort and resources devoted to these processes, a fraction of the lipids and lipid-like compounds frequently remains in the extracts. These low-level lipids foul injection liners, contaminate columns, and yield elevated baselines during gas chromatographic analysis of synthetic musk compounds. In this study, a simple method for the determination of synthetic musk compounds in fish tissues has been developed. Closed-loop stripping of saponified fish tissues in a I -L Wheaton purge- and-trap vessel, is used to strip compounds with high vapor pressures such as synthetic musks from the matrix onto a solid sorbent (Abselut Nexus). This technique is useful for screening biological tissues that contain lipids for musk compounds. Analytes are desorbed from the sorbent trap sequentially with polar an

  18. Physicochemical and toxicological characteristics of welding fume derived particles generated from real time welding processes.

    PubMed

    Chang, Cali; Demokritou, Philip; Shafer, Martin; Christiani, David

    2013-01-01

    Welding fume particles have been well studied in the past; however, most studies have examined welding fumes generated from machine models rather than actual exposures. Furthermore, the link between physicochemical and toxicological properties of welding fume particles has not been well understood. This study aims to investigate the physicochemical properties of particles derived during real time welding processes generated during actual welding processes and to assess the particle size specific toxicological properties. A compact cascade impactor (Harvard CCI) was stationed within the welding booth to sample particles by size. Size fractionated particles were extracted and used for both off-line physicochemical analysis and in vitro cellular toxicological characterization. Each size fraction was analyzed for ions, elemental compositions, and mass concentration. Furthermore, real time optical particle monitors (DustTrak™, TSI Inc., Shoreview, Minn.) were used in the same welding booth to collect real time PM2.5 particle number concentration data. The sampled particles were extracted from the polyurethane foam (PUF) impaction substrates using a previously developed and validated protocol, and used in a cellular assay to assess oxidative stress. By mass, welding aerosols were found to be in coarse (PM 2.5–10), and fine (PM 0.1–2.5) size ranges. Most of the water soluble (WS) metals presented higher concentrations in the coarse size range with some exceptions such as sodium, which presented elevated concentration in the PM 0.1 size range. In vitro data showed size specific dependency, with the fine and ultrafine size ranges having the highest reactive oxygen species (ROS) activity. Additionally, this study suggests a possible correlation between welders' experience, the welding procedure and equipment used and particles generated from welding fumes. Mass concentrations and total metal and water soluble metal concentrations of welding fume particles may be

  19. A real-time multi-channel monitoring system for stem cell culture process.

    PubMed

    Xicai Yue; Drakakis, E M; Lim, M; Radomska, A; Hua Ye; Mantalaris, A; Panoskaltsis, N; Cass, A

    2008-06-01

    A novel, up to 128 channels, multi-parametric physiological measurement system suitable for monitoring hematopoietic stem cell culture processes and cell cultures in general is presented in this paper. The system aims to measure in real-time the most important physical and chemical culture parameters of hematopoietic stem cells, including physicochemical parameters, nutrients, and metabolites, in a long-term culture process. The overarching scope of this research effort is to control and optimize the whole bioprocess by means of the acquisition of real-time quantitative physiological information from the culture. The system is designed in a modular manner. Each hardware module can operate as an independent gain programmable, level shift adjustable, 16 channel data acquisition system specific to a sensor type. Up to eight such data acquisition modules can be combined and connected to the host PC to realize the whole system hardware. The control of data acquisition and the subsequent management of data is performed by the system's software which is coded in LabVIEW. Preliminary experimental results presented here show that the system not only has the ability to interface to various types of sensors allowing the monitoring of different types of culture parameters. Moreover, it can capture dynamic variations of culture parameters by means of real-time multi-channel measurements thus providing additional information on both temporal and spatial profiles of these parameters within a bioreactor. The system is by no means constrained in the hematopoietic stem cell culture field only. It is suitable for cell growth monitoring applications in general.

  20. Reading Between the Spikes: Real-Time Signal Processing in Neural Systems

    NASA Astrophysics Data System (ADS)

    Warland, David Karsten

    This thesis discusses biological strategies for real-time signal processing in neural systems. Nearly all creatures encode information about the world as patterns of identically shaped action potentials, or "spikes". As a result, all the animal's knowledge of the world is contained in the occurrence times of these discrete events. Traditional approaches to the study of neural coding emphasize the encoding process, resulting in predictions of average neural responses to a limited class of stimuli. However, these studies fail to address the relevant biological question: What can the organism "learn" about the outside world from real-time observations of its own spike trains? Therefore, this thesis approaches neural coding from the point of view of the organism itself: We learn to decode neural spike trains to obtain real-time estimates of sensory stimuli. In particular, this ability to extract continuous signals from spiking cells, together with the definition of an equivalent spectral noise level for a spiking neuron allows characterization of the information contained in patterns of neural response as well as forming the basis for the prediction of optimal neural computation strategies with spike trains. These methods are applied to the design and analysis of experiments on a single wide field, movement -sensitive neuron (H1) in the visual system of the blowfly Calliphora erythrocephela and to the filiform hair receptors of the wind-sensing system of the cricket Acheta domestica. This thesis also discusses the generalization of these strategies to collections of neurons and the applications to future work in the context of neural computation in the retina.

  1. Design of a Real-time Signal Processing System for LIF Sensor

    NASA Astrophysics Data System (ADS)

    Xian-de, Zhao; Wen-gang, Zheng; Da-ming, Dong; Chang-jun, Shen; Xin, Zhang; Jian-jun, Zhou; hua, Yan; Wen-biao, Wu

    2011-02-01

    Laser Induced Fluorescence (LIF) sensor is one of the most sensitive approaches available for a variety of analytical applications, such as determination of nitrogen content of plant leaves, detection of chlorophyll content in water, etal. As a core instrumental requirements of real time LIF sensor, signal processing system is used to store effective processing and identification algorithms in a short time. By analyzing the working principle of LIF sensor in detail, a novel platform of signal processing system used in LIF sensor is proposed in this paper. The design solutions and hardware architecture of the system are described in this paper, include Digital Signal Processor (DSP), data transmission block, and memory block. Several steps of signal processing methods are proposed, according to the characteristic of LIF sensor. At last, an application of using the signal processing system designed in this paper for measuring chlorophyll content in plant leaves is shown.

  2. High-throughput data acquisition and processing for real-time x-ray imaging

    NASA Astrophysics Data System (ADS)

    Vogelgesang, Matthias; Rota, Lorenzo; Ardila Perez, Luis E.; Caselle, Michele; Chilingaryan, Suren; Kopmann, Andreas

    2016-10-01

    With ever-increasing data rates due to stronger light sources and better detectors, X-ray imaging experiments conducted at synchrotron beamlines face bandwidth and processing limitations that inhibit efficient workflows and prevent real-time operations. We propose an experiment platform comprised of programmable hardware and optimized software to lift these limitations and make beamline setups future-proof. The hardware consists of an FPGA-based data acquisition system with custom logic for data pre-processing and a PCIe data connection for transmission of currently up to 6.6 GB/s. Moreover, the accompanying firmware supports pushing data directly into GPU memory using AMD's DirectGMA technology without crossing system memory first. The GPUs are used to pre-process projection data and reconstruct final volumetric data with OpenCL faster than possible with CPUs alone. Besides, more efficient use of resources this enables a real-time preview of a reconstruction for early quality assessment of both experiment setup and the investigated sample. The entire system is designed in a modular way and allows swapping all components, e.g. replacing our custom FPGA camera with a commercial system but keep reconstructing data with GPUs. Moreover, every component is accessible using a low-level C library or using a high-level Python interface in order to integrate these components in any legacy environment.

  3. Peta-Flop Real Time Radio Astronomy Signal Processing Instrumentation and the CASPER Collaboration

    NASA Astrophysics Data System (ADS)

    Werthimer, Dan

    2014-04-01

    I will briefly describe next generation radio telescopes, such as HERA and the Square Kilometer Array (SKA), which will require 1E15 to 1E17 operations per second of real time processing. I'll present some of the new architectures we've used to develop a variety of heterogeneous FPGA-GPU-CPU based signal processing systems for such telescopes, including spectrometers, correlators, and beam formers. I will also describe the CASPER collaboration, which has developed architectures, open source programming tools, libraries and reference designs that make it relatively easy to develop a variety of scalable, upgradeable, fault tolerant, low power, real time digital signal processing instrumentation. CASPER utilizes commercial 10Gbit and 40 Gbit ethernet switches to interconnect open source general purpose field programmable gate array (FPGA) boards with GPUs and software modules. CASPER collaborators at hundreds of universities, government labs and observatories have used these techniques to rapidly develop and deploy a variety of correlators, beamformers, spectrometers, pulsar/transient machines, and VLBI instrumentation. CASPER instrumentation is also utilized in physics, medicine, genomics and engineering. Open source source hardware, software, libraries, tools, tutorials, reference designs, information about workshops, and how to join the collaboration are available at http://casper.berkeley.edu

  4. A microscope automated fluidic system to study bacterial processes in real time.

    PubMed

    Ducret, Adrien; Maisonneuve, Etienne; Notareschi, Philippe; Grossi, Alain; Mignot, Tâm; Dukan, Sam

    2009-09-30

    Most time lapse microscopy experiments studying bacterial processes ie growth, progression through the cell cycle and motility have been performed on thin nutrient agar pads. An important limitation of this approach is that dynamic perturbations of the experimental conditions cannot be easily performed. In eukaryotic cell biology, fluidic approaches have been largely used to study the impact of rapid environmental perturbations on live cells and in real time. However, all these approaches are not easily applicable to bacterial cells because the substrata are in all cases specific and also because microfluidics nanotechnology requires a complex lithography for the study of micrometer sized bacterial cells. In fact, in many cases agar is the experimental solid substratum on which bacteria can move or even grow. For these reasons, we designed a novel hybrid micro fluidic device that combines a thin agar pad and a custom flow chamber. By studying several examples, we show that this system allows real time analysis of a broad array of biological processes such as growth, development and motility. Thus, the flow chamber system will be an essential tool to study any process that take place on an agar surface at the single cell level.

  5. Real-time software processing and audio reproduction of directional Doppler signals.

    PubMed

    Fidanzati, Paolo; Morganti, Tiziano; Tortoli, Piero

    2005-12-01

    In ultrasound Doppler systems, directional signals are typically obtained by processing quadrature demodulated data with dedicated analog or digital circuits. In this paper, a software approach is proposed, that allows fully exploiting the reproduction and recording capabilities of low-cost personal computer sound cards and/or embedded chips. Forward/reverse signals are separated through a wideband Hilbert filter. No limitations are imposed on the input signal sample rate, which is matched to the standard output format of sound cards through a band-limited interpolation filter controlled in a feedback loop. The digital audio streaming is performed in real-time in a Windows-based application. The processed data are in a standard format compatible with real-time recording in waveform or compressed files, as requested in many research applications. Simulations and in vivo tests show a typical cross talk of -50 dB between forward and reverse components, with low latency time (39 ms) and central processing unit load compatible to currently available personal computers.

  6. A Microscope Automated Fluidic System to Study Bacterial Processes in Real Time

    PubMed Central

    Ducret, Adrien; Maisonneuve, Etienne; Notareschi, Philippe; Grossi, Alain; Mignot, Tâm; Dukan, Sam

    2009-01-01

    Most time lapse microscopy experiments studying bacterial processes ie growth, progression through the cell cycle and motility have been performed on thin nutrient agar pads. An important limitation of this approach is that dynamic perturbations of the experimental conditions cannot be easily performed. In eukaryotic cell biology, fluidic approaches have been largely used to study the impact of rapid environmental perturbations on live cells and in real time. However, all these approaches are not easily applicable to bacterial cells because the substrata are in all cases specific and also because microfluidics nanotechnology requires a complex lithography for the study of micrometer sized bacterial cells. In fact, in many cases agar is the experimental solid substratum on which bacteria can move or even grow. For these reasons, we designed a novel hybrid micro fluidic device that combines a thin agar pad and a custom flow chamber. By studying several examples, we show that this system allows real time analysis of a broad array of biological processes such as growth, development and motility. Thus, the flow chamber system will be an essential tool to study any process that take place on an agar surface at the single cell level. PMID:19789641

  7. Bringing closed-loop home: recent advances in closed-loop insulin delivery.

    PubMed

    Thabit, Hood; Hovorka, Roman

    2014-04-01

    To highlight the recent advances in closed-loop research, the development and progress towards utilizing closed loop outside of the clinical research setting and at patients' homes. In spite of the modern insulin therapy in type 1 diabetes, hypoglycaemia is still a major limiting factor. This often leads to suboptimal glycaemic control and risk of diabetes complications. Closed loop has been shown to improve glycaemic control whilst avoiding hypoglycaemia. Incremental progress has been made in this field, from the use of automated systems and bihormonal closed-loop systems in clinical research facility settings under close supervision to the use of ambulatory closed-loop prototype at patients' homes in free-living conditions. Different population of patients with type 1 diabetes and control algorithm approaches have been studied, assessing the efficacy and safety. Transitional and home studies present different challenges at achieving better glycaemic outcome with closed loop. Improved glucose sensor reliability may accelerate the clinical use and faster insulin analogues increase the clinical utility. Results and experience with closed-loop insulin delivery have been encouraging, leading the way for future improvements and development in the field, to make closed loop suitable for use in clinical practice.

  8. Study on algorithm and real-time implementation of infrared image processing based on FPGA

    NASA Astrophysics Data System (ADS)

    Pang, Yulin; Ding, Ruijun; Liu, Shanshan; Chen, Zhe

    2010-10-01

    With the fast development of Infrared Focal Plane Arrays (IRFPA) detectors, high quality real-time image processing becomes more important in infrared imaging system. Facing the demand of better visual effect and good performance, we find FPGA is an ideal choice of hardware to realize image processing algorithm that fully taking advantage of its high speed, high reliability and processing a great amount of data in parallel. In this paper, a new idea of dynamic linear extension algorithm is introduced, which has the function of automatically finding the proper extension range. This image enhancement algorithm is designed in Verilog HDL and realized on FPGA. It works on higher speed than serial processing device like CPU and DSP. Experiment shows that this hardware unit of dynamic linear extension algorithm enhances the visual effect of infrared image effectively.

  9. Process Synchronization and Data Communication between Processes in Real Time Local Area Networks.

    DTIC Science & Technology

    1985-12-01

    refinement [Ref. 6], and S.G. Klinefelter , June 1982, dynamical interaction with the operating system during execution [Ref. 7]. W.R. Rowe, June 1984, put the... history of the system, and outlines the goals of this thesis. Chapter II discusses three different approaches studied in developing the concept of...onterey, Mhsi si N avaJ. ostgrauare S 00 i~Ty California, tbecember 1981. 7. Klinefelter , S.G.IImplementation of a Real-Time, Distributed

  10. A design of real time image capturing and processing system using Texas Instrument's processor

    NASA Astrophysics Data System (ADS)

    Wee, Toon-Joo; Chaisorn, Lekha; Rahardja, Susanto; Gan, Woon-Seng

    2007-09-01

    In this work, we developed and implemented an image capturing and processing system that equipped with capability of capturing images from an input video in real time. The input video can be a video from a PC, video camcorder or DVD player. We developed two modes of operation in the system. In the first mode, an input image from the PC is processed on the processing board (development platform with a digital signal processor) and is displayed on the PC. In the second mode, current captured image from the video camcorder (or from DVD player) is processed on the board but is displayed on the LCD monitor. The major difference between our system and other existing conventional systems is that image-processing functions are performed on the board instead of the PC (so that the functions can be used for further developments on the board). The user can control the operations of the board through the Graphic User Interface (GUI) provided on the PC. In order to have a smooth image data transfer between the PC and the board, we employed Real Time Data Transfer (RTDX TM) technology to create a link between them. For image processing functions, we developed three main groups of function: (1) Point Processing; (2) Filtering and; (3) 'Others'. Point Processing includes rotation, negation and mirroring. Filter category provides median, adaptive, smooth and sharpen filtering in the time domain. In 'Others' category, auto-contrast adjustment, edge detection, segmentation and sepia color are provided, these functions either add effect on the image or enhance the image. We have developed and implemented our system using C/C# programming language on TMS320DM642 (or DM642) board from Texas Instruments (TI). The system was showcased in College of Engineering (CoE) exhibition 2006 at Nanyang Technological University (NTU) and have more than 40 users tried our system. It is demonstrated that our system is adequate for real time image capturing. Our system can be used or applied for

  11. Real-Time Detection Methods to Monitor TRU Compositions in UREX+Process Streams

    SciTech Connect

    McDeavitt, Sean; Charlton, William; Indacochea, J Ernesto; taleyarkhan, Rusi; Pereira, Candido

    2013-03-01

    The U.S. Department of Energy has developed advanced methods for reprocessing spent nuclear fuel. The majority of this development was accomplished under the Advanced Fuel Cycle Initiative (AFCI), building on the strong legacy of process development R&D over the past 50 years. The most prominent processing method under development is named UREX+. The name refers to a family of processing methods that begin with the Uranium Extraction (UREX) process and incorporate a variety of other methods to separate uranium, selected fission products, and the transuranic (TRU) isotopes from dissolved spent nuclear fuel. It is important to consider issues such as safeguards strategies and materials control and accountability methods. Monitoring of higher actinides during aqueous separations is a critical research area. By providing on-line materials accountability for the processes, covert diversion of the materials streams becomes much more difficult. The importance of the nuclear fuel cycle continues to rise on national and international agendas. The U.S. Department of Energy is evaluating and developing advanced methods for safeguarding nuclear materials along with instrumentation in various stages of the fuel cycle, especially in material balance areas (MBAs) and during reprocessing of used nuclear fuel. One of the challenges related to the implementation of any type of MBA and/or reprocessing technology (e.g., PUREX or UREX) is the real-time quantification and control of the transuranic (TRU) isotopes as they move through the process. Monitoring of higher actinides from their neutron emission (including multiplicity) and alpha signatures during transit in MBAs and in aqueous separations is a critical research area. By providing on-line real-time materials accountability, diversion of the materials becomes much more difficult. The objective of this consortium was to develop real time detection methods to monitor the efficacy of the UREX+ process and to safeguard the separated

  12. Real-Time On-Board Processing Validation of MSPI Ground Camera Images

    NASA Technical Reports Server (NTRS)

    Pingree, Paula J.; Werne, Thomas A.; Bekker, Dmitriy L.

    2010-01-01

    The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA's Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA including PowerPC440 processors we have implemented a least squares fitting algorithm that extracts intensity and polarimetric parameters in real-time, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information.

  13. Real-time processing of off-axis interferograms: from the camera to the user

    NASA Astrophysics Data System (ADS)

    Girshovitz, Pinhas; Gabay, Tamir; Shaked, Natan T.

    2014-07-01

    We review new algorithms that have been presented by us lately1 for fast reconstruction and phase unwrapping of sample wave-fronts recorded using off-axis digital holographic imaging. These algorithms enable reconstruction and phase unwrapping of sample wave-fronts up to 16 times faster than the conventional Fourier-based reconstruction algorithm. The algorithms exploit the compression properties of holographic imaging for decreasing the calculation complexity required for extracting the sample wave-front from the recorded interferogram. Using the presented algorithms, we were able to reconstruct, for the first time, 1 Mega pixels off-axis interferograms in more than 30 frames per second using a standard single-core personal computer on a Matlab-Labview interface, without using a graphic processing-unit programming or parallel computing. This computational speedup is important for real-time visualization, calculation and data extraction for dynamic samples and processes that are evaluated using off-axis digital holography such as biological cell imaging and real-time nondestructive testing.

  14. Real-time digital signal processing in multiphoton and time-resolved microscopy

    NASA Astrophysics Data System (ADS)

    Wilson, Jesse W.; Warren, Warren S.; Fischer, Martin C.

    2016-03-01

    The use of multiphoton interactions in biological tissue for imaging contrast requires highly sensitive optical measurements. These often involve signal processing and filtering steps between the photodetector and the data acquisition device, such as photon counting and lock-in amplification. These steps can be implemented as real-time digital signal processing (DSP) elements on field-programmable gate array (FPGA) devices, an approach that affords much greater flexibility than commercial photon counting or lock-in devices. We will present progress toward developing two new FPGA-based DSP devices for multiphoton and time-resolved microscopy applications. The first is a high-speed multiharmonic lock-in amplifier for transient absorption microscopy, which is being developed for real-time analysis of the intensity-dependence of melanin, with applications in vivo and ex vivo (noninvasive histopathology of melanoma and pigmented lesions). The second device is a kHz lock-in amplifier running on a low cost (50-200) development platform. It is our hope that these FPGA-based DSP devices will enable new, high-speed, low-cost applications in multiphoton and time-resolved microscopy.

  15. Study on in situ and real-time observation during process of SCN crystal growth

    NASA Astrophysics Data System (ADS)

    Lei, Songhe; Chen, Changle; Duan, Mengmeng

    2006-02-01

    Crystal growth is dynamic coupling of transportation process and growth process between interfaces. Convection during crystal growth will tend to changes of liquation component and the defect of impurity stripe. The convection and stability should further be studied to obtain the crystal of high quality. It is necessary to obtain surface configuration and distribution of temperature around liquation phase and solute concentration. The technique of in-situ and real-time observation is a brand new technique, which is widely applied to production and scientific research. Information of crystal growth will be obtained from the observation. But the in-situ and real-time observation is uncharitableness for the experiment equipment, some conditions matched to the character of crystal must be provided. In the paper a design with ingenious and cheap crystal growth cell and circulation system of constant-temperature water which is suitable for the experiment of observation is developed, and a combined light path based on the technique of flowing visualization is designed to match to the crystal cell. The combined light path which is made up of the schlieren method and the principle of Mach-zehnder interference is non destructive, high sensitivity and observable, so it is an effective method to study the crystal growth.

  16. Real-Time On-Board Processing Validation of MSPI Ground Camera Images

    NASA Technical Reports Server (NTRS)

    Pingree, Paula J.; Werne, Thomas A.; Bekker, Dmitriy L.

    2010-01-01

    The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA's Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA including PowerPC440 processors we have implemented a least squares fitting algorithm that extracts intensity and polarimetric parameters in real-time, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information.

  17. [Real time diagnostics of instantaneous temperature of combustion and explosion process by modern spectroscopy].

    PubMed

    Zhou, Xue-tie; Wang, Jun-de; Li, Yan; Liu, Da-bing

    2003-04-01

    The combustion temperature is one of the important parameters to express flame combustion and explosion characteristics. It will effectively guide the design and manufacture of new model explosives, industrial explosive materials, and weapons. The recent developments and applications of real time diagnostics of instantaneous temperature of combustion and explosion processes by modern spectroscopic methods, such as atomic absorption-emission method, atomic emission two-line spectroscopy, atomic emission multiline spectroscopy, molecular rotation-vibration spectroscopy, coherent anti-stokes Raman scattering (CARS) and plane laser-induced fluorescence (PLIF), were reviewed in this paper. The maximum time resolution of atomic absorption-emission method is 25 microseconds. The time resolution of atomic emission two-line spectroscopy can reach 0.1 microsecond. These two methods can completely suit the need of real time and instantaneous temperature diagnostics of violent explosion and flame combustion. Other methods will also provide new effective research methods for the processes and characteristics of combustion, flame and explosion.

  18. Real-time processing in picture naming in adults who stutter: ERP evidence

    PubMed Central

    Maxfield, Nathan D.; Morris, Kalie; Frisch, Stefan A.; Morphew, Kathryn; Constantine, Joseph L.

    2014-01-01

    Objective The aim was to compare real-time language/cognitive processing in picture naming in adults who stutter (AWS) versus typically-fluent adults (TFA). Methods Participants named pictures preceded by masked prime words. Primes and target picture labels were Identical or mismatched. Priming effects on naming and picture-elicited ERP activity were analyzed. Vocabulary knowledge correlations with these measures were assessed. Results Priming improved naming RTs and accuracy in both groups. RTs were longer for AWS, and correlated positively with receptive vocabulary in TFA. Electrophysiologically, posterior-P1 amplitude negatively correlated with expressive vocabulary in TFA versus receptive vocabulary in AWS. Frontal/temporal-P1 amplitude correlated positively with expressive vocabulary in AWS. Identity priming enhanced frontal/posterior-N2 amplitude in both groups, and attenuated P280 amplitude in AWS. N400 priming was topographically-restricted in AWS. Conclusions Results suggest that conceptual knowledge was perceptually-grounded in expressive vocabulary in TFA versus receptive vocabulary in AWS. Poorer expressive vocabulary in AWS was potentially associated with greater suppression of irrelevant conceptual information. Priming enhanced N2-indexed cognitive control and visual attention in both groups. P280-indexed focal attention attenuated with priming in AWS only. Topographically-restricted N400 priming suggests that lemma/word form connections were weaker in AWS. Significance Real-time language/cognitive processing in picture naming operates differently in AWS. PMID:24910149

  19. Delay-Dependent Response in Weakly Electric Fish under Closed-Loop Pulse Stimulation

    PubMed Central

    Forlim, Caroline Garcia; Pinto, Reynaldo Daniel; Varona, Pablo; Rodríguez, Francisco B.

    2015-01-01

    In this paper, we apply a real time activity-dependent protocol to study how freely swimming weakly electric fish produce and process the timing of their own electric signals. Specifically, we address this study in the elephant fish, Gnathonemus petersii, an animal that uses weak discharges to locate obstacles or food while navigating, as well as for electro-communication with conspecifics. To investigate how the inter pulse intervals vary in response to external stimuli, we compare the response to a simple closed-loop stimulation protocol and the signals generated without electrical stimulation. The activity-dependent stimulation protocol explores different stimulus delivery delays relative to the fish’s own electric discharges. We show that there is a critical time delay in this closed-loop interaction, as the largest changes in inter pulse intervals occur when the stimulation delay is below 100 ms. We also discuss the implications of these findings in the context of information processing in weakly electric fish. PMID:26473597

  20. A novel time-domain signal processing algorithm for real time ventricular fibrillation detection

    NASA Astrophysics Data System (ADS)

    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.

  1. Demonstration of real-time monitoring of a photolithographic exposure process using chemical ionization mass spectrometry

    SciTech Connect

    Mowry, C.D.

    1998-02-01

    Silicon wafers are coated with photoresist and exposed to ultraviolet (UV) light in a laboratory to simulate typical conditions expected in an actual semiconductor manufacturing process tool. Air is drawn through the exposure chamber and analyzed using chemical ionization mass spectrometry (CI/MS). Species that evaporate or outgas from the wafer are thus detected. The purpose of such analyses is to determine the potential of CI/MS as a real-time process monitoring tool. Results demonstrate that CI/MS can remotely detect the products evolved before, during, and after wafer UV exposure; and that the quantity and type of products vary with the photoresist coated on the wafer. Such monitoring could provide semiconductor manufacturers benefits in quality control and process analysis. Tool and photoresist manufacturers could also realize benefits from this measurement technique with respect to new tool, method, or photoresist development. The benefits realized can lead to improved device yields and reduced product and development costs.

  2. A high speed data acquisition and processing system for real time data analysis and control

    NASA Astrophysics Data System (ADS)

    Ferron, J. R.

    1992-11-01

    A high speed data acquisition system which is closely coupled with a high speed digital processor is described. Data acquisition at a rate of 40 million 14 bit data values per second is possible simultaneously with data processing at a rate of 80 million floating point operations per second. This is achieved by coupling a commercially available VME format single board computer based on the Intel i860 microprocessor with a custom designed first-in, first-out memory circuit that transfers data at high speed to the processor board memory. Parallel processing to achieve increased computation speed is easily implemented because the data can be transferred simultaneously to multiple processor boards. Possible applications include high speed process control and real time data reduction. A specific example is described in which this hardware is used to implement a feedback control system for 18 parameters which uses 100 input signals and achieves a 100 μs cycle time.

  3. All-IP-Ethernet architecture for real-time sensor-fusion processing

    NASA Astrophysics Data System (ADS)

    Hiraki, Kei; Inaba, Mary; Tezuka, Hiroshi; Tomari, Hisanobu; Koizumi, Kenichi; Kondo, Shuya

    2016-03-01

    Serendipter is a device that distinguishes and selects very rare particles and cells from huge amount of population. We are currently designing and constructing information processing system for a Serendipter. The information processing system for Serendipter is a kind of sensor-fusion system but with much more difficulties: To fulfill these requirements, we adopt All IP based architecture: All IP-Ethernet based data processing system consists of (1) sensor/detector directly output data as IP-Ethernet packet stream, (2) single Ethernet/TCP/IP streams by a L2 100Gbps Ethernet switch, (3) An FPGA board with 100Gbps Ethernet I/F connected to the switch and a Xeon based server. Circuits in the FPGA include 100Gbps Ethernet MAC, buffers and preprocessing, and real-time Deep learning circuits using multi-layer neural networks. Proposed All-IP architecture solves existing problem to construct large-scale sensor-fusion systems.

  4. Novel closed-loop approaches for precise relative navigation of widely separated GPS receivers in LEO

    NASA Astrophysics Data System (ADS)

    Tancredi, U.; Renga, A.; Grassi, M.

    2014-01-01

    This paper deals with the relative navigation of a formation of two spacecrafts separated by hundreds of kilometers based on processing dual-frequency differential carrier-phase GPS measurements. Specific requirements of the considered application are high relative positioning accuracy and real-time on board implementation. These can be conflicting requirements. Indeed, if on one hand high accuracy can be achieved by exploiting the integer nature of double-difference carrier-phase ambiguities, on the other hand the presence of large ephemeris errors and differential ionospheric delays makes the integer ambiguities determination challenging. Closed-loop schemes, which update the relative position estimates of a dynamic filter with feedback from integer ambiguities fixing algorithms, are customarily employed in these cases. This paper further elaborates such approaches, proposing novel closed loop techniques aimed at overcoming some of the limitations of traditional algorithms. They extend techniques developed for spaceborne long baseline relative positioning by making use of an on-the-fly ambiguity resolution technique especially developed for the applications of interest. Such techniques blend together ionospheric delay compensation techniques, nonlinear models of relative spacecraft dynamics, and partial integer validation techniques. The approaches are validated using flight data from the Gravity Recovery and Climate Experiment (GRACE) mission. Performance is compared to that of the traditional closed-loop scheme analyzing the capability of each scheme to maximize the percentage of correctly fixed integer ambiguities as well as the relative positioning accuracy. Results show that the proposed approach substantially improves performance of the traditional approaches. More specifically, centimeter-level root-mean square relative positioning is feasible for spacecraft separations of more than 260 km, and an integer ambiguity fixing performance as high as 98% is

  5. Signal quality and Bayesian signal processing in neurofeedback based on real-time fMRI.

    PubMed

    Koush, Yury; Zvyagintsev, Mikhail; Dyck, Miriam; Mathiak, Krystyna A; Mathiak, Klaus

    2012-01-02

    Real-time fMRI allows analysis and visualization of the brain activity online, i.e. within one repetition time. It can be used in neurofeedback applications where subjects attempt to control an activation level in a specified region of interest (ROI) of their brain. The signal derived from the ROI is contaminated with noise and artifacts, namely with physiological noise from breathing and heart beat, scanner drift, motion-related artifacts and measurement noise. We developed a Bayesian approach to reduce noise and to remove artifacts in real-time using a modified Kalman filter. The system performs several signal processing operations: subtraction of constant and low-frequency signal components, spike removal and signal smoothing. Quantitative feedback signal quality analysis was used to estimate the quality of the neurofeedback time series and performance of the applied signal processing on different ROIs. The signal-to-noise ratio (SNR) across the entire time series and the group event-related SNR (eSNR) were significantly higher for the processed time series in comparison to the raw data. Applied signal processing improved the t-statistic increasing the significance of blood oxygen level-dependent (BOLD) signal changes. Accordingly, the contrast-to-noise ratio (CNR) of the feedback time series was improved as well. In addition, the data revealed increase of localized self-control across feedback sessions. The new signal processing approach provided reliable neurofeedback, performed precise artifacts removal, reduced noise, and required minimal manual adjustments of parameters. Advanced and fast online signal processing algorithms considerably increased the quality as well as the information content of the control signal which in turn resulted in higher contingency in the neurofeedback loop.

  6. Validation of Real-Time Data Processing for the Ground and Air-MSPI Systems

    NASA Technical Reports Server (NTRS)

    Werne, Thomas; Bekker, Dmitriy L.; Pingree, Paula J.

    2011-01-01

    JPL is currently developing the multi-angle spectro-polarimetric imager (MSPI), targeted for the Aerosol-Cloud-Ecosystems (ACE) mission, as defined in the National Academies 2007 Decadal Survey. In preparation for the space instrument, the MSPI team has built two incremental camera systems (Ground- and Air-MSPI) to improve understanding of the proposed architecture. Ground-MSPI is a gimballed instrument used primarily for stationary observation and characterization of the imager and optics. The ER-2 based Air-MSPI operates in a step-and-stare mode, providing multi-angle imaging of a static target. This mode-of-operation simulates the observation scenario of the space instrument. Physically, MSPI is a pushbroom camera with a specialized frontend. Before imaging, light entering the camera passes through a pair of photoelastic modulators and a set of pattern polarizers. These optical elements act on the light to make polarimetric extraction computationally feasible. Calculating polarimetric parameters from the imager's data stream requires a real-time least-squares computation that produces coefficients of a truncated time-series expansion of the image. As reported in, the data processing algorithm can operate in real-time on a Xilinx Virtex-5 FPGA. Moving beyond verification with an onboard data source, the algorithm has been validated on a commercial development board interfaced with the ground camera. In addition, the algorithm has been instantiated within the Air-MSPI electronics board's FPGA, and in situ first-light has been achieved.

  7. Real-time performance analysis of wireless multimedia networks based on partially observed multivariate point processes

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    2000-07-01

    Third-generation (3G) wireless networks will support integrated multimedia services based on a cellular extension of a packet-switched architecture using variants of the Internet protocol (IP). Services can be categorized as real- time and delay-sensitive, or non-real-time and delay- insensitive. Each call, arriving to or active within the network, carries demand for one or more services in parallel; each service type with a guaranteed quality of service (QoS). Admission of new calls to the wireless IP network (WIN) from the gateway of a wired network or from a mobile subscriber (MS) is allowed by call admission control procedures. Roaming of the MSs among the nodes of the WIN is controlled by handoff procedures between base stations (BSs), or BS controllers, and the MSs. Metrics such as the probabilities of call blocking and dropping, handoff transition time, processing latency of a call, throughput, and capacity are used to evaluate the performance of network control procedures. The metrics are directly related to the network resources required to provide the QoS for the integrated services.

  8. Real-time image processing for passive mmW imagery

    NASA Astrophysics Data System (ADS)

    Kozacik, Stephen; Paolini, Aaron; Bonnett, James; Harrity, Charles; Mackrides, Daniel; Dillon, Thomas E.; Martin, Richard D.; Schuetz, Christopher A.; Kelmelis, Eric; Prather, Dennis W.

    2015-05-01

    The transmission characteristics of millimeter waves (mmWs) make them suitable for many applications in defense and security, from airport preflight scanning to penetrating degraded visual environments such as brownout or heavy fog. While the cold sky provides sufficient illumination for these images to be taken passively in outdoor scenarios, this utility comes at a cost; the diffraction limit of the longer wavelengths involved leads to lower resolution imagery compared to the visible or IR regimes, and the low power levels inherent to passive imagery allow the data to be more easily degraded by noise. Recent techniques leveraging optical upconversion have shown significant promise, but are still subject to fundamental limits in resolution and signal-to-noise ratio. To address these issues we have applied techniques developed for visible and IR imagery to decrease noise and increase resolution in mmW imagery. We have developed these techniques into fieldable software, making use of GPU platforms for real-time operation of computationally complex image processing algorithms. We present data from a passive, 77 GHz, distributed aperture, video-rate imaging platform captured during field tests at full video rate. These videos demonstrate the increase in situational awareness that can be gained through applying computational techniques in real-time without needing changes in detection hardware.

  9. Processing real-time stereo video for an autonomous robot using disparity maps and sensor fusion

    NASA Astrophysics Data System (ADS)

    Rosselot, Donald W.; Hall, Ernest L.

    2004-10-01

    The Bearcat "Cub" Robot is an interactive, intelligent, Autonomous Guided Vehicle (AGV) designed to serve in unstructured environments. Recent advances in computer stereo vision algorithms that produce quality disparity and the availability of low cost high speed camera systems have simplified many of tasks associated with robot navigation and obstacle avoidance using stereo vision. Leveraging these benefits, this paper describes a novel method for autonomous navigation and obstacle avoidance currently being implemented on the UC Bearcat Robot. The core of this approach is the synthesis of multiple sources of real-time data including stereo image disparity maps, tilt sensor data, and LADAR data with standard contour, edge, color, and line detection methods to provide robust and intelligent obstacle avoidance. An algorithm is presented with Matlab code to process the disparity maps to rapidly produce obstacle size and location information in a simple format, and features cancellation of noise and correction for pitch and roll. The vision and control computers are clustered with the Parallel Virtual Machine (PVM) software. The significance of this work is in presenting the methods needed for real time navigation and obstacle avoidance for intelligent autonomous robots.

  10. Improved radar data processing algorithms for quantitative rainfall estimation in real time.

    PubMed

    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.

  11. Real-time network security situation visualization and threat assessment based on semi-Markov process

    NASA Astrophysics Data System (ADS)

    Chen, Junhua

    2013-03-01

    To cope with a large amount of data in current sensed environments, decision aid tools should provide their understanding of situations in a time-efficient manner, so there is an increasing need for real-time network security situation awareness and threat assessment. In this study, the state transition model of vulnerability in the network based on semi-Markov process is proposed at first. Once events are triggered by an attacker's action or system response, the current states of the vulnerabilities are known. Then we calculate the transition probabilities of the vulnerability from the current state to security failure state. Furthermore in order to improve accuracy of our algorithms, we adjust the probabilities that they exploit the vulnerability according to the attacker's skill level. In the light of the preconditions and post-conditions of vulnerabilities in the network, attack graph is built to visualize security situation in real time. Subsequently, we predict attack path, recognize attack intention and estimate the impact through analysis of attack graph. These help administrators to insight into intrusion steps, determine security state and assess threat. Finally testing in a network shows that this method is reasonable and feasible, and can undertake tremendous analysis task to facilitate administrators' work.

  12. Software-Based Real-Time Acquisition and Processing of PET Detector Raw Data.

    PubMed

    Goldschmidt, Benjamin; Schug, David; Lerche, Christoph W; Salomon, André; Gebhardt, Pierre; Weissler, Bjoern; Wehner, Jakob; Dueppenbecker, Peter M; Kiessling, Fabian; Schulz, Volkmar

    2016-02-01

    In modern positron emission tomography (PET) readout architectures, the position and energy estimation of scintillation events (singles) and the detection of coincident events (coincidences) are typically carried out on highly integrated, programmable printed circuit boards. The implementation of advanced singles and coincidence processing (SCP) algorithms for these architectures is often limited by the strict constraints of hardware-based data processing. In this paper, we present a software-based data acquisition and processing architecture (DAPA) that offers a high degree of flexibility for advanced SCP algorithms through relaxed real-time constraints and an easily extendible data processing framework. The DAPA is designed to acquire detector raw data from independent (but synchronized) detector modules and process the data for singles and coincidences in real-time using a center-of-gravity (COG)-based, a least-squares (LS)-based, or a maximum-likelihood (ML)-based crystal position and energy estimation approach (CPEEA). To test the DAPA, we adapted it to a preclinical PET detector that outputs detector raw data from 60 independent digital silicon photomultiplier (dSiPM)-based detector stacks and evaluated it with a [(18)F]-fluorodeoxyglucose-filled hot-rod phantom. The DAPA is highly reliable with less than 0.1% of all detector raw data lost or corrupted. For high validation thresholds (37.1 ± 12.8 photons per pixel) of the dSiPM detector tiles, the DAPA is real time capable up to 55 MBq for the COG-based CPEEA, up to 31 MBq for the LS-based CPEEA, and up to 28 MBq for the ML-based CPEEA. Compared to the COG-based CPEEA, the rods in the image reconstruction of the hot-rod phantom are only slightly better separable and less blurred for the LS- and ML-based CPEEA. While the coincidence time resolution (∼ 500 ps) and energy resolution (∼12.3%) are comparable for all three CPEEA, the system sensitivity is up to 2.5 × higher for the LS- and ML-based CPEEA.

  13. Real time explosive hazard information sensing, processing, and communication for autonomous operation

    DOEpatents

    Versteeg, Roelof J; Few, Douglas A; Kinoshita, Robert A; Johnson, Doug; Linda, Ondrej

    2015-02-24

    Methods, computer readable media, and apparatuses provide robotic explosive hazard detection. A robot intelligence kernel (RIK) includes a dynamic autonomy structure with two or more autonomy levels between operator intervention and robot initiative A mine sensor and processing module (ESPM) operating separately from the RIK perceives environmental variables indicative of a mine using subsurface perceptors. The ESPM processes mine information to determine a likelihood of a presence of a mine. A robot can autonomously modify behavior responsive to an indication of a detected mine. The behavior is modified between detection of mines, detailed scanning and characterization of the mine, developing mine indication parameters, and resuming detection. Real time messages are passed between the RIK and the ESPM. A combination of ESPM bound messages and RIK bound messages cause the robot platform to switch between modes including a calibration mode, the mine detection mode, and the mine characterization mode.

  14. Real time explosive hazard information sensing, processing, and communication for autonomous operation

    DOEpatents

    Versteeg, Roelof J.; Few, Douglas A.; Kinoshita, Robert A.; Johnson, Douglas; Linda, Ondrej

    2015-12-15

    Methods, computer readable media, and apparatuses provide robotic explosive hazard detection. A robot intelligence kernel (RIK) includes a dynamic autonomy structure with two or more autonomy levels between operator intervention and robot initiative A mine sensor and processing module (ESPM) operating separately from the RIK perceives environmental variables indicative of a mine using subsurface perceptors. The ESPM processes mine information to determine a likelihood of a presence of a mine. A robot can autonomously modify behavior responsive to an indication of a detected mine. The behavior is modified between detection of mines, detailed scanning and characterization of the mine, developing mine indication parameters, and resuming detection. Real time messages are passed between the RIK and the ESPM. A combination of ESPM bound messages and RIK bound messages cause the robot platform to switch between modes including a calibration mode, the mine detection mode, and the mine characterization mode.

  15. The Information Adaptive System - A demonstration of real-time onboard image processing

    NASA Technical Reports Server (NTRS)

    Thomas, G. L.; Carney, P. C.; Meredith, B. D.

    1983-01-01

    The Information Adaptive System (IAS) program has the objective to develop and demonstrate, at the brassboard level, an architecture which can be used to perform advanced signal procesing functions on board the spacecraft. Particular attention is given to the processing of high-speed multispectral imaging data in real-time, and the development of advanced technology which could be employed for future space applications. An IAS functional description is provided, and questions of radiometric correction are examined. Problems of data packetization are considered along with data selection, a distortion coefficient processor, an adaptive system controller, an image processing demonstration system, a sensor simulator and output data buffer, a test support and demonstration controller, and IAS demonstration operating modes.

  16. Reverse engineering of free-form surface based on the closed-loop theory.

    PubMed

    He, Xue Ming; He, Jun Fei; Wu, Mei Ping; Zhang, Rong; Ji, Xiao Gang

    2015-01-01

    To seek better methods of measurement and more accurate model of reconstruction in the field of reverse engineering has been the focus of researchers. Based on this, a new method of adaptive measurement, real-time reconstruction, and online evaluation of free-form surface was presented in this paper. The coordinates and vectors of the prediction points are calculated according to a Bézier curve which is fitted by measured points. Final measured point cloud distribution is in agreement with the geometric characteristics of the free-form surfaces. Fitting the point cloud to a surface model by the nonuniform B-spline method, extracting some check points from the surface models based on grids and a feature on the surface, review the location of these check points on the surface with CMM and evaluate the model, and then update the surface model to meet the accuracy. Integrated measurement, reconstruction, and evaluation, with the closed-loop reverse process, established an accurate model. The results of example show that the measuring points are distributed over the surface according to curvature, and the reconstruction model can be completely expressed with micron level. Meanwhile, measurement, reconstruction and evaluation are integrated in forms of closed-loop reverse system.

  17. Real-time fMRI processing with physiological noise correction - Comparison with off-line analysis.

    PubMed

    Misaki, Masaya; Barzigar, Nafise; Zotev, Vadim; Phillips, Raquel; Cheng, Samuel; Bodurka, Jerzy

    2015-12-30

    While applications of real-time functional magnetic resonance imaging (rtfMRI) are growing rapidly, there are still limitations in real-time data processing compared to off-line analysis. We developed a proof-of-concept real-time fMRI processing (rtfMRIp) system utilizing a personal computer (PC) with a dedicated graphic processing unit (GPU) to demonstrate that it is now possible to perform intensive whole-brain fMRI data processing in real-time. The rtfMRIp performs slice-timing correction, motion correction, spatial smoothing, signal scaling, and general linear model (GLM) analysis with multiple noise regressors including physiological noise modeled with cardiac (RETROICOR) and respiration volume per time (RVT). The whole-brain data analysis with more than 100,000voxels and more than 250volumes is completed in less than 300ms, much faster than the time required to acquire the fMRI volume. Real-time processing implementation cannot be identical to off-line analysis when time-course information is used, such as in slice-timing correction, signal scaling, and GLM. We verified that reduced slice-timing correction for real-time analysis had comparable output with off-line analysis. The real-time GLM analysis, however, showed over-fitting when the number of sampled volumes was small. Our system implemented real-time RETROICOR and RVT physiological noise corrections for the first time and it is capable of processing these steps on all available data at a given time, without need for recursive algorithms. Comprehensive data processing in rtfMRI is possible with a PC, while the number of samples should be considered in real-time GLM. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Sub-millisecond closed-loop feedback stimulation between arbitrary sets of individual neurons

    PubMed Central

    Müller, Jan; Bakkum, Douglas J.; Hierlemann, Andreas

    2012-01-01

    We present a system to artificially correlate the spike timing between sets of arbitrary neurons that were interfaced to a complementary metal–oxide–semiconductor (CMOS) high-density microelectrode array (MEA). The system features a novel reprogrammable and flexible event engine unit to detect arbitrary spatio-temporal patterns of recorded action potentials and is capable of delivering sub-millisecond closed-loop feedback of electrical stimulation upon trigger events in real-time. The relative timing between action potentials of individual neurons as well as the temporal pattern among multiple neurons, or neuronal assemblies, is considered an important factor governing memory and learning in the brain. Artificially changing timings between arbitrary sets of spiking neurons with our system could provide a “knob” to tune information processing in the network. PMID:23335887

  19. Distributed real time data processing architecture for the TJ-II data acquisition system

    SciTech Connect

    Ruiz, M.; Barrera, E.; Lopez, S.; Machon, D.; Vega, J.; Sanchez, E.

    2004-10-01

    This article describes the performance of a new model of architecture that has been developed for the TJ-II data acquisition system in order to increase its real time data processing capabilities. The current model consists of several compact PCI extension for instrumentation (PXI) standard chassis, each one with various digitizers. In this architecture, the data processing capability is restricted to the PXI controller's own performance. The controller must share its CPU resources between the data processing and the data acquisition tasks. In the new model, distributed data processing architecture has been developed. The solution adds one or more processing cards to each PXI chassis. This way it is possible to plan how to distribute the data processing of all acquired signals among the processing cards and the available resources of the PXI controller. This model allows scalability of the system. More or less processing cards can be added based on the requirements of the system. The processing algorithms are implemented in LabVIEW (from National Instruments), providing efficiency and time-saving application development when compared with other efficient solutions.

  20. Modelling effluent quality based on a real-time optical monitoring of the wastewater treatment process.

    PubMed

    Tomperi, Jani; Koivuranta, Elisa; Kuokkanen, Anna; Leiviskä, Kauko

    2017-01-01

    A novel optical monitoring device was used for imaging an activated sludge process in situ during a period of over one year. In this study, the dependencies between the results of image analysis and the process measurements were studied, and the optical monitoring results were utilized to predict the important quality parameters for the wastewater treatment process efficiency: suspended solids, biological oxygen demand, chemical oxygen demand, total nitrogen and total phosphorous in biologically treated wastewater. The optimal subsets of variables for each model were searched using five variable selection methods. It was shown that online optical analysis results have clear dependencies on some process variables and the purification result. The model based on optical monitoring and process variables from the early stage of the treatment process can be used to predict the levels of important quality parameters, and to show the quality of the biologically treated wastewater hours in advance. This study confirms that the optical monitoring method is a valuable tool for monitoring a wastewater treatment process and receiving new information in real time. Combined with predictive modelling, it has the potential to be used in process control, keeping the process in a stable operating condition and avoiding environmental risks.

  1. Processing, Cataloguing and Distribution of Uas Images in Near Real Time

    NASA Astrophysics Data System (ADS)

    Runkel, I.

    2013-08-01

    can be checked and interpreted in near real-time. For sensible areas it gives you the possibility to inform remote decision makers or interpretation experts in order to provide them situations awareness, wherever they are. For monitoring and inspection tasks it speeds up the process of data capture and data interpretation. The fully automated workflow of data pre-processing, data georeferencing, data cataloguing and data dissemination in near real time was developed based on the Intergraph products ERDAS IMAGINE, ERDAS APOLLO and GEOSYSTEMS METAmorph!IT. It is offered as adaptable solution by GEOSYSTEMS GmbH.

  2. Advanced time-of-flight range camera with novel real-time 3D image processing

    NASA Astrophysics Data System (ADS)

    Koenig, Bernhard; Hosticka, Bedrich; Mengel, Peter; Listl, Ludwig

    2007-09-01

    We present a solid state range camera covering measuring distances from 2 m to 25 m and novel real-time 3D image processing algorithms for object detection, tracking and classification based on the three-dimensional features of the camera's output data. The technology is based on a 64x8 pixel array CMOS image sensor which is capable of capturing three-dimensional images by executing indirect time-of-flight (ToF) measurement of NIR laser pulses emitted by the camera and reflected by the objects in the cameras field of view. Here the so-called "multiple double short time integration" (MDSI) method enables unprecedented reliability and robustness with respect to suppression of background irradiance and insensitiveness to reflectivity variations in the object scene. Output data are conventional intensity values and distance values with accuracies in the centimeter range at image repetition rates up to 100 Hz. An evaluation of the camera's performance in typical road safety related test scenarios is subject of this paper. Furthermore we introduce real-time image processing of the output data stream of the camera aiming at the segmentation of objects being located in the camera's surrounding and the derivation of reliable position, speed and acceleration estimates. The segmentation algorithm utilizes the position information of all three spatial dimensions as well as the intensity values and thus yields significant segmentation improvement compared to segmentation in conventional 2D pictures. Position, velocity and acceleration values of the segmented objects are estimated by means of Kalman filtering in 3D space. The filter is dynamically adapting to the measurement conditions to take care of changes of the scene data properties. Flow and performance of the whole processing chain are presented by means of example scenes.

  3. Intensity Maps Production Using Real-Time Joint Streaming Data Processing From Social and Physical Sensors

    NASA Astrophysics Data System (ADS)

    Kropivnitskaya, Y. Y.; Tiampo, K. F.; Qin, J.; Bauer, M.

    2015-12-01

    Intensity is one of the most useful measures of earthquake hazard, as it quantifies the strength of shaking produced at a given distance from the epicenter. Today, there are several data sources that could be used to determine intensity level which can be divided into two main categories. The first category is represented by social data sources, in which the intensity values are collected by interviewing people who experienced the earthquake-induced shaking. In this case, specially developed questionnaires can be used in addition to personal observations published on social networks such as Twitter. These observations are assigned to the appropriate intensity level by correlating specific details and descriptions to the Modified Mercalli Scale. The second category of data sources is represented by observations from different physical sensors installed with the specific purpose of obtaining an instrumentally-derived intensity level. These are usually based on a regression of recorded peak acceleration and/or velocity amplitudes. This approach relates the recorded ground motions to the expected felt and damage distribution through empirical relationships. The goal of this work is to implement and evaluate streaming data processing separately and jointly from both social and physical sensors in order to produce near real-time intensity maps and compare and analyze their quality and evolution through 10-minute time intervals immediately following an earthquake. Results are shown for the case study of the M6.0 2014 South Napa, CA earthquake that occurred on August 24, 2014. The using of innovative streaming and pipelining computing paradigms through IBM InfoSphere Streams platform made it possible to read input data in real-time for low-latency computing of combined intensity level and production of combined intensity maps in near-real time. The results compare three types of intensity maps created based on physical, social and combined data sources. Here we correlate

  4. Real-time model based process monitoring of enzymatic biodiesel production.

    PubMed

    Price, Jason; Nordblad, Mathias; Woodley, John M; Huusom, Jakob K

    2015-01-01

    In this contribution we extend our modelling work on the enzymatic production of biodiesel where we demonstrate the application of a Continuous-Discrete Extended Kalman Filter (a state estimator). The state estimator is used to correct for mismatch between the process data and the process model for Fed-batch production of biodiesel. For the three process runs investigated, using a single tuning parameter, qx  = 2 × 10(-2) which represents the uncertainty in the process model, it was possible over the entire course of the reaction to reduce the overall mean and standard deviation of the error between the model and the process data for all of the five measured components (triglycerides, diglycerides, monoglycerides, fatty acid methyl esters, and free fatty acid). The most significant reduction for the three process runs, were for the monoglyceride and free fatty acid concentration. For those components, there was over a ten-fold decrease in the overall mean error for the state estimator prediction compared with the predictions from the pure model simulations. It is also shown that the state estimator can be used as a tool for detection of outliers in the measurement data. For the enzymatic biodiesel process, given the infrequent and sometimes uncertain measurements obtained we see the use of the Continuous-Discrete Extended Kalman Filter as a viable tool for real time process monitoring.

  5. A Real-Time Optical Tracking and Measurement Processing System for Flying Targets

    PubMed Central

    Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

    2014-01-01

    Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control. PMID:24987748

  6. A generic FPGA-based detector readout and real-time image processing board

    NASA Astrophysics Data System (ADS)

    Sarpotdar, Mayuresh; Mathew, Joice; Safonova, Margarita; Murthy, Jayant

    2016-07-01

    For space-based astronomical observations, it is important to have a mechanism to capture the digital output from the standard detector for further on-board analysis and storage. We have developed a generic (application- wise) field-programmable gate array (FPGA) board to interface with an image sensor, a method to generate the clocks required to read the image data from the sensor, and a real-time image processor system (on-chip) which can be used for various image processing tasks. The FPGA board is applied as the image processor board in the Lunar Ultraviolet Cosmic Imager (LUCI) and a star sensor (StarSense) - instruments developed by our group. In this paper, we discuss the various design considerations for this board and its applications in the future balloon and possible space flights.

  7. The application of digital computers to near-real-time processing of flutter test data

    NASA Technical Reports Server (NTRS)

    Hurley, S. R.

    1976-01-01

    Procedures used in monitoring, analyzing, and displaying flight and ground flutter test data are presented. These procedures include three digital computer programs developed to process structural response data in near real time. Qualitative and quantitative modal stability data are derived from time history response data resulting from rapid sinusoidal frequency sweep forcing functions, tuned-mode quick stops, and pilot induced control pulses. The techniques have been applied to both fixed and rotary wing aircraft, during flight, whirl tower rotor systems tests, and wind tunnel flutter model tests. An hydraulically driven oscillatory aerodynamic vane excitation system utilized during the flight flutter test programs accomplished during Lockheed L-1011 and S-3A development is described.

  8. Real-time embedded system for stereo video processing for multiview displays

    NASA Astrophysics Data System (ADS)

    Berretty, R.-P. M.; Riemens, A. K.; Machado, P. F.

    2007-02-01

    In video systems, the introduction of 3D video might be the next revolution after the introduction of color. Nowadays multiview auto-stereoscopic displays are entering the market. Such displays offer various views at the same time. Depending on its positions, the viewers' eyes see different images. Hence, the viewers' left eye receives a signal that is different from what his right eye gets; this gives, provided the signals have been properly processed, the impression of depth. New auto-stereoscopic products use an image-plus-depth interface. On the other hand, a growing number of 3D productions from the entertainment industry use a stereo format. In this paper, we show how to compute depth from the stereo signal to comply with the display interface format. Furthermore, we present a realisation suitable for a real-time cost-effective implementation on an embedded media processor.

  9. Counting People and Recognizing Wheelchairs at Elevator Lobby by Real-Time Image Processing

    NASA Astrophysics Data System (ADS)

    Uchidate, Hikaru; Inoda, Ryosuke; Tsuji, Toshiaki; Abe, Shigeru

    This paper proposes a real-time image processing system for wheelchair recognition at elevator lobby. This system extracts objects with frame difference method. From the image of extracted objects, heads of people are detected by the Hough transform. Vertical shooting from ceiling improves the performance of people counting since the detected head has high roundness and occlusion of people is prevented. Two feature quantities are introduced to recognize wheelchairs. They are the area value and the ratio of traveling length to vertical length. Since these quantities require a method for drawing the contour line. This paper proposes a new simple method to draw a contour line. The effectiveness of this system is confirmed through experiments.

  10. Real-time brain activity measurement and signal processing system using highly sensitive MI sensor

    NASA Astrophysics Data System (ADS)

    Wang, Kewang; Cai, Changmei; Yamamoto, Michiharu; Uchiyama, Tsuyoshi

    2017-05-01

    Superconducting Quantum Interference Devices (SQUIDs) are the most used sensor to detect the extremely weak magnetic field of brain. However, the sensor heads need to be kept at very low temperature to maintain superconductivity, and that makes the devices large-scale and inconvenient. In order to measure brain activity in normal environment, we had constructed a measurement system based on highly sensitive Magneto-Impedance (MI) sensor, and reported the study of measuring Auditory Evoked Field (AEF) brain waves. In this study, the system was improved, and the sensor signals can be processed in real-time to monitor brain activity. We use this system to measure the alpha rhythm in the occipital region and the Event-Related Field (ERF) P300 in the frontal, the parietal and both the temporal regions.

  11. Rapid process development of chromatographic process using direct analysis in real time mass spectrometry as a process analytical technology tool.

    PubMed

    Yan, Binjun; Chen, Teng; Xu, Zhilin; Qu, Haibin

    2014-06-01

    The concept of quality by design (QbD) is widely applied in the process development of pharmaceuticals. However, the additional cost and time have caused some resistance about QbD implementation. To show a possible solution, this work proposed a rapid process development method, which used direct analysis in real time mass spectrometry (DART-MS) as a process analytical technology (PAT) tool for studying the chromatographic process of Ginkgo biloba L., as an example. The breakthrough curves were fast determined by DART-MS at-line. A high correlation coefficient of 0.9520 was found between the concentrations of ginkgolide A determined by DART-MS and HPLC. Based on the PAT tool, the impacts of process parameters on the adsorption capacity were discovered rapidly, which showed a decreased adsorption capacity with the increase of the flow rate. This work has shown the feasibility and advantages of integrating PAT into QbD implementation for rapid process development.

  12. Global grid of master events for waveform cross-correlation: from testing to real time processing

    NASA Astrophysics Data System (ADS)

    Bobrov, Dmitry; Rozhkov, Mikhail; Kitov, Ivan

    2014-05-01

    Seismic monitoring of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) requires a globally uniform detection threshold, which is provided by geographical distribution of the Primary Seismic Network of the International Monitoring System (IMS). This detection threshold has to be as low as allowed by the entire set of real time and historical data recorded by the IMS. The International Data Centre (IDC) analyzes all relevant data in automatic processing and interactive review to issue a Reviewed Event Bulletin (REB), which includes all qualified events as obtained for the purpose of nuclear test monitoring. Since 2000, raw data, individual detections, and created events are saved in the IDC archive currently reaching tens of terabyte. In order to effectively use this archive in global monitoring we introduced the waveform cross correlation (matched filter) technique. Cross correlation between real time records at IMS stations and template waveforms is calculated for a dense (spacing of ~ 140 km) and regular grid of master events uniformly covering the globe. There are approximately 25,000 master events with 3 to 10 templates at IMS stations. In seismically active zones, we populate masters with real waveforms. For aseismic zones, we develop an extended set of synthetic templates for virtual master events. For optimal performance of cross correlation, the Principal and Independent Component Analysis are applied to the historical (from earthquakes and underground nuclear tests) and synthetic waveforms. Real waveform templates and selected PCA/ICA components are used in automatic processing for the production of a tentative cross-correlation standard event list (XSEL).

  13. Real-time gesture interface based on event-driven processing from stereo silicon retinas.

    PubMed

    Lee, Jun Haeng; Delbruck, Tobi; Pfeiffer, Michael; Park, Paul K J; Shin, Chang-Woo; Ryu, Hyunsurk Eric; Kang, Byung Chang

    2014-12-01

    We propose a real-time hand gesture interface based on combining a stereo pair of biologically inspired event-based dynamic vision sensor (DVS) silicon retinas with neuromorphic event-driven postprocessing. Compared with conventional vision or 3-D sensors, the use of DVSs, which output asynchronous and sparse events in response to motion, eliminates the need to extract movements from sequences of video frames, and allows significantly faster and more energy-efficient processing. In addition, the rate of input events depends on the observed movements, and thus provides an additional cue for solving the gesture spotting problem, i.e., finding the onsets and offsets of gestures. We propose a postprocessing framework based on spiking neural networks that can process the events received from the DVSs in real time, and provides an architecture for future implementation in neuromorphic hardware devices. The motion trajectories of moving hands are detected by spatiotemporally correlating the stereoscopically verged asynchronous events from the DVSs by using leaky integrate-and-fire (LIF) neurons. Adaptive thresholds of the LIF neurons achieve the segmentation of trajectories, which are then translated into discrete and finite feature vectors. The feature vectors are classified with hidden Markov models, using a separate Gaussian mixture model for spotting irrelevant transition gestures. The disparity information from stereovision is used to adapt LIF neuron parameters to achieve recognition invariant of the distance of the user to the sensor, and also helps to filter out movements in the background of the user. Exploiting the high dynamic range of DVSs, furthermore, allows gesture recognition over a 60-dB range of scene illuminance. The system achieves recognition rates well over 90% under a variety of variable conditions with static and dynamic backgrounds with naïve users.

  14. Side-scan sonar mapping: Pseudo-real-time processing and mosaicking techniques

    SciTech Connect

    Danforth, W.W.; Schwab, W.C.; O'Brien, T.F. ); Karl, H. )

    1990-05-01

    The US Geological Survey (USGS) surveyed 1,000 km{sup 2} of the continental shelf off San Francisco during a 17-day cruise, using a 120-kHz side-scan sonar system, and produced a digitally processed sonar mosaic of the survey area. The data were processed and mosaicked in real time using software developed at the Lamont-Doherty Geological Observatory and modified by the USGS, a substantial task due to the enormous amount of data produced by high-resolution side-scan systems. Approximately 33 megabytes of data were acquired every 1.5 hr. The real-time sonar images were displayed on a PC-based workstation and the data were transferred to a UNIX minicomputer where the sonar images were slant-range corrected, enhanced using an averaging method of desampling and a linear-contrast stretch, merged with navigation, geographically oriented at a user-selected scale, and finally output to a thermal printer. The hard-copy output was then used to construct a mosaic of the survey area. The final product of this technique is a UTM-projected map-mosaic of sea-floor backscatter variations, which could be used, for example, to locate appropriate sites for sediment sampling to ground truth the sonar imagery while still at sea. More importantly, reconnaissance surveys of this type allow for the analysis and interpretation of the mosaic during a cruise, thus greatly reducing the preparation time needed for planning follow-up studies of a particular area.

  15. Real-time investigation of nucleic acids phosphorylation process using molecular beacons

    PubMed Central

    Tang, Zhiwen; Wang, Kemin; Tan, Weihong; Ma, Changbei; Li, Jun; Liu, Lingfeng; Guo, Qiuping; Meng, Xiangxian

    2005-01-01

    Phosphorylation of nucleic acids is an indispensable process to repair strand interruption of nucleic acids. We have studied the process of phosphorylation using molecular beacon (MB) DNA probes in real-time and with high selectivity. The MB employed in this method is devised to sense the product of a ‘phosphorylation–ligation’ coupled enzyme reaction. Compared with the current assays, this novel method is convenient, fast, selective, highly sensitive and capable of real-time monitoring in a homogenous solution. The preference of T4 polynucleotide kinase (T4 PNK) has been investigated using this approach. The results revealed that a single-stranded oligonucleotide containing guanine at the 5′ termini is most preferred, while those utilizing cytosine in this location are least preferred. The preference of (T)9 was reduced greatly when phosphoryl was modified at the 5′ end, implying that T4 PNK could discern the phosphorylated/unphosphorylated oligonucleotides. The increase of oligonucleotide DNA length leads to an enhancement in preference. A fast and accurate method for assaying the kinase activity of T4 PNK has been developed with a wide linear detection range from 0.002 to 4.0 U/ml in 3 min. The effects of certain factors, such as NTP, ADP, (NH4)2SO4 and Na2HPO4, on phosphorylation have been investigated. This novel approach enables us to investigate the interactions between proteins and nucleic acids in a homogenous solution, such as those found in DNA repair or in drug development. PMID:15961728

  16. Efficient Data Capture and Post-Processing for Real-Time Imaging Using AN Ultrasonic Array

    NASA Astrophysics Data System (ADS)

    Moreau, L.; Hunter, A. J.; Drinkwater, B. W.; Wilcox, P. D.

    2010-02-01

    Over the past few years, ultrasonic phased arrays have shown good potential for nondestructive testing (NDT), thanks to high resolution imaging algorithms. Many algorithms are based on the full matrix capture, obtained by firing each element of an ultrasonic array independently, and collecting the data with all elements. Because of the finite sound velocity in the specimen, two consecutive firings must be separated by a minimum time interval. Therefore, more array elements require longer data acquisition times. Moreover, if the array has N elements, then the full matrix contains N2 temporal signals to be processed. Because of the limited calculation speed of current computers, a large matrix of data can result in long post-processing times. In an industrial context where real-time imaging is desirable, it is crucial to reduce acquisition and/or post-processing times. This paper investigates methods designed to reduce acquisition and post-processing times for the total focusing method and wavenumber imaging algorithms. Limited transmission cycles are used to reduce data capture and post-processing. Post-processing times are further reduced by demodulating the data to temporal baseband frequencies. Results are presented so that a compromise can be made between acquisition time, post-processing time and image quality.

  17. Multi-Isotope Process (MIP) Monitor: A Near-Real-Time Monitor For Reprocessing Facilities

    SciTech Connect

    Schwantes, Jon M.; Douglas, Matthew; Orton, Christopher R.; Fraga, Carlos G.; Christensen, Richard

    2008-06-01

    INTRODUCTION The threat of protracted diversion of Pu from commercial reprocessing operations is perhaps the greatest concern to national and international agencies tasked with safeguarding these facilities. While it is generally understood that a method for direct monitoring of process on-line and in near-real time (NRT) would be the best defense against protracted diversion scenarios, an effective method with these qualities has yet to be developed. Here, we attempt to bridge this gap by proposing an on-line NRT process monitoring method that should be sensitive to minor alterations in process conditions and compatible with small, easily deployable, detection systems. This Approach is known as the Multi-Isotope Process (MIP) Monitor and involves the determination and recognition of the contaminant pattern within a process stream for a suite of indicator (radioactive) elements present in the spent fuel as a function of process variables. Utilization of a suite of radio-elements, including ones with multiple oxidation states, decreases the likelihood that attempts to divert Pu by altering the ReDox environment within the process would go undetected. In addition, by identifying gamma-emitting indicator isotopes, this Approach might eliminate the need for bulky neutron detection systems, relying instead on small, portable, high-resolution gamma detectors easily deployable throughout the facility.

  18. Real time monitoring of reticle etch process tool to investigate and predict critical dimension performance

    NASA Astrophysics Data System (ADS)

    Deming, Rick; Yung, Karmen; Guglielmana, Mark; Bald, Dan; Baik, Kiho; Abboud, Frank

    2007-03-01

    As mask pattern feature sizes shrink the need for tighter control of factors affecting critical dimensions (CD) increases at all steps in the mask manufacturing process. To support this requirement Intel Mask Operation is expanding its process and equipment monitoring capability. We intend to better understand the factors affecting the process and enhance our ability to predict reticle health and critical dimension performance. This paper describes a methodology by which one can predict the contribution of the dry etch process equipment to overall CD performance. We describe the architecture used to collect critical process related information from various sources both internal and external to the process equipment and environment. In addition we discuss the method used to assess the significance of each parameter and to construct the statistical model used to generate the predictions. We further discuss the methodology used to turn this model into a functioning real time prediction of critical dimension performance. Further, these predictions will be used to modify the manufacturing decision support system to provide early detection for process excursion.

  19. [Applying graphics processing unit in real-time signal processing and visualization of ophthalmic Fourier-domain OCT system].

    PubMed

    Liu, Qiaoyan; Li, Yuejie; Xu, Qiujing; Zhao, Jincheng; Wang, Liwei; Gao, Yonghe

    2013-01-01

    This investigation introduces GPU (Graphics Processing Unit)- based CUDA (Compute Unified Device Architecture) technology into signal processing of ophthalmic FD-OCT (Fourier-Domain Optical Coherence Tomography) imaging system, can realize parallel data processing, using CUDA to optimize relevant operations and algorithms, in order to solve the technical bottlenecks that currently affect ophthalmic real-time imaging in OCT system. Laboratory results showed that with GPU as a general parallel computing processor, the speed of imaging data processing using GPU+CPU mode is more than dozens times faster than traditional CPU platform based serial computing and imaging mode when executing the same data processing, which reaches the clinical requirements for two dimensional real-time imaging.

  20. Novel Real-Time Diagnosis of the Freezing Process Using an Ultrasonic Transducer

    PubMed Central

    Tseng, Yen-Hsiang; Cheng, Chin-Chi; Cheng, Hong-Ping; Lee, Dasheng

    2015-01-01

    The freezing stage governs several critical parameters of the freeze drying process and the quality of the resulting lyophilized products. This paper presents an integrated ultrasonic transducer (UT) in a stainless steel bottle and its application to real-time diagnostics of the water freezing process. The sensor was directly deposited onto the stainless steel bottle using a sol-gel spray technique. It could operate at temperature range from −100 to 400 °C and uses an ultrasonic pulse-echo technique. The progression of the freezing process, including water-in, freezing point and final phase change of water, were all clearly observed using ultrasound. The ultrasonic signals could indicate the three stages of the freezing process and evaluate the cooling and freezing periods under various processing conditions. The temperature was also adopted for evaluating the cooling and freezing periods. These periods increased with water volume and decreased with shelf temperature (i.e., speed of freezing). This study demonstrates the effectiveness of the ultrasonic sensor and technology for diagnosing and optimizing the process of water freezing to save energy. PMID:25946629

  1. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation †

    PubMed Central

    Ibrahim, Ali; Gastaldo, Paolo; Chible, Hussein; Valle, Maurizio

    2017-01-01

    Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots), biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted. PMID:28287448

  2. Real-time display on Fourier domain optical coherence tomography system using a graphics processing unit.

    PubMed

    Watanabe, Yuuki; Itagaki, Toshiki

    2009-01-01

    Fourier domain optical coherence tomography (FD-OCT) requires resampling of spectrally resolved depth information from wavelength to wave number, and the subsequent application of the inverse Fourier transform. The display rates of OCT images are much slower than the image acquisition rates due to processing speed limitations on most computers. We demonstrate a real-time display of processed OCT images using a linear-in-wave-number (linear-k) spectrometer and a graphics processing unit (GPU). We use the linear-k spectrometer with the combination of a diffractive grating with 1200 lines/mm and a F2 equilateral prism in the 840-nm spectral region to avoid calculating the resampling process. The calculations of the fast Fourier transform (FFT) are accelerated by the GPU with many stream processors, which realizes highly parallel processing. A display rate of 27.9 frames/sec for processed images (2048 FFT size x 1000 lateral A-scans) is achieved in our OCT system using a line scan CCD camera operated at 27.9 kHz.

  3. Real-Time Digital Signal Processing Based on FPGAs for Electronic Skin Implementation †.

    PubMed

    Ibrahim, Ali; Gastaldo, Paolo; Chible, Hussein; Valle, Maurizio

    2017-03-10

    Enabling touch-sensing capability would help appliances understand interaction behaviors with their surroundings. Many recent studies are focusing on the development of electronic skin because of its necessity in various application domains, namely autonomous artificial intelligence (e.g., robots), biomedical instrumentation, and replacement prosthetic devices. An essential task of the electronic skin system is to locally process the tactile data and send structured information either to mimic human skin or to respond to the application demands. The electronic skin must be fabricated together with an embedded electronic system which has the role of acquiring the tactile data, processing, and extracting structured information. On the other hand, processing tactile data requires efficient methods to extract meaningful information from raw sensor data. Machine learning represents an effective method for data analysis in many domains: it has recently demonstrated its effectiveness in processing tactile sensor data. In this framework, this paper presents the implementation of digital signal processing based on FPGAs for tactile data processing. It provides the implementation of a tensorial kernel function for a machine learning approach. Implementation results are assessed by highlighting the FPGA resource utilization and power consumption. Results demonstrate the feasibility of the proposed implementation when real-time classification of input touch modalities are targeted.

  4. Novel real-time diagnosis of the freezing process using an ultrasonic transducer.

    PubMed

    Tseng, Yen-Hsiang; Cheng, Chin-Chi; Cheng, Hong-Ping; Lee, Dasheng

    2015-05-04

    The freezing stage governs several critical parameters of the freeze drying process and the quality of the resulting lyophilized products. This paper presents an integrated ultrasonic transducer (UT) in a stainless steel bottle and its application to real-time diagnostics of the water freezing process. The sensor was directly deposited onto the stainless steel bottle using a sol-gel spray technique. It could operate at temperature range from -100 to 400 °C and uses an ultrasonic pulse-echo technique. The progression of the freezing process, including water-in, freezing point and final phase change of water, were all clearly observed using ultrasound. The ultrasonic signals could indicate the three stages of the freezing process and evaluate the cooling and freezing periods under various processing conditions. The temperature was also adopted for evaluating the cooling and freezing periods. These periods increased with water volume and decreased with shelf temperature (i.e., speed of freezing). This study demonstrates the effectiveness of the ultrasonic sensor and technology for diagnosing and optimizing the process of water freezing to save energy.

  5. Large Scale GPS Processing at ESOC for LEO, GNSS and Real-Time Applications

    NASA Astrophysics Data System (ADS)

    Boomkamp, H.; Dow, J.

    2003-12-01

    Most POD systems that are used in GPS data analysis, for instance in routine IGS processing, are large FORTRAN programs that have evolved from early generation systems over many years of use. These systems do not exploit the advantages of modern software engineering technology, and their limited processing efficiency constrains their application to emerging large-scale GPS processes, like real-time GPS, high-rate data processing or combined solutions for LEO + MEO constellations. In support of such high-performance applications, the ESOC IGS Analysis Centre is developing a new POD system based on the latest software engineering methods. This system is optimised in its use of both CPU and memory, following fundamental rules of minimum information containment that are more commonly found in internet search engines or artificial intelligence applications. Although this new system still has an experimental status it is expected to augment the GPS data processing capacity at ESOC by at least one order of magnitude. Some innovative concepts behind the system will be presented, together with first examples of GPS processes that until now were prohibitively large or slow.

  6. A translational platform for prototyping closed-loop neuromodulation systems.

    PubMed

    Afshar, Pedram; Khambhati, Ankit; Stanslaski, Scott; Carlson, David; Jensen, Randy; Linde, Dave; Dani, Siddharth; Lazarewicz, Maciej; Cong, Peng; Giftakis, Jon; Stypulkowski, Paul; Denison, Tim

    2012-01-01

    While modulating neural activity through stimulation is an effective treatment for neurological diseases such as Parkinson's disease and essential tremor, an opportunity for improving neuromodulation therapy remains in automatically adjusting therapy to continuously optimize patient outcomes. Practical issues associated with achieving this include the paucity of human data related to disease states, poorly validated estimators of patient state, and unknown dynamic mappings of optimal stimulation parameters based on estimated states. To overcome these challenges, we present an investigational platform including: an implanted sensing and stimulation device to collect data and run automated closed-loop algorithms; an external tool to prototype classifier and control-policy algorithms; and real-time telemetry to update the implanted device firmware and monitor its state. The prototyping system was demonstrated in a chronic large animal model studying hippocampal dynamics. We used the platform to find biomarkers of the observed states and transfer functions of different stimulation amplitudes. Data showed that moderate levels of stimulation suppress hippocampal beta activity, while high levels of stimulation produce seizure-like after-discharge activity. The biomarker and transfer function observations were mapped into classifier and control-policy algorithms, which were downloaded to the implanted device to continuously titrate stimulation amplitude for the desired network effect. The platform is designed to be a flexible prototyping tool and could be used to develop improved mechanistic models and automated closed-loop systems for a variety of neurological disorders.

  7. Mock Circulatory Loop Compliance Chamber Employing a Novel Real-Time Control Process.

    PubMed

    Taylor, Charles E; Miller, Gerald E

    2012-12-01

    The use of compliance chambers in mock circulatory loop construction is the predominant means of simulating arterial compliance. Utilizing mock circulatory loops as bench test methods for cardiac assist technologies necessitates that they must be capable of reproducing the circulatory conditions that would exist physiologically. Of particular interest is the ability to determine instantaneous compliance of the system, and the ability to change the compliance in real-time. This capability enables continuous battery testing of conditions without stopping the flow to change the compliance chamber settings, and the simulation of dynamic changes in arterial compliance. The method tested involves the use of a compliance chamber utilizing a circular natural latex rubber membrane separating the fluid and air portions of the device. Change in system compliance is affected by the airspace pressure, which creates more reaction force at the membrane to the fluid pressure. A pressure sensor in the fluid portion of the chamber and a displacement sensor monitoring membrane center deflection allow for real-time inputs to the control algorithm. A predefined numerical model correlates the displacement sensor data to the volume displacement of the membrane. The control algorithm involves a tuned π loop maintaining the volume distention of the membrane via regulation of the air space pressure. The proportional integral (PI) controller tuning was achieved by creating a computational model of the compliance chamber using Simulink™ Simscape(®) toolboxes. These toolboxes were used to construct a model of the hydraulic, mechanical, and pneumatic elements in the physical design. Parameter Estimation™ tools and Design Optimization™ methods were employed to determine unknown physical parameters in the system, and tune the process controller used to maintain the compliance setting. It was found that the resulting control architecture was capable of maintaining compliance along a

  8. Integration of real time quality control systems in a welding process

    SciTech Connect

    Nava-Ruediger, E.; Houlot, M.

    1997-04-01

    The automation of laser welding processes requires the control of the various process components as well as the control of the laser-material interaction. These systems are essential for ensuring the quality of the weld seam as they are able to react to dynamic fluctuations during the process. During the process various phenomena occur which are potential sources of diagnostic signals: these include thermal, electrical, optical, mechanical and acoustic events. This paper presents the development of an integrated real-time system based on the monitoring of several of these phenomena that provide complementary information for the detection of different defect types. A system based on the use of infrared photodiodes has been validated and successfully applied to the detection of the appearance of geometric defects such as sagging or misalignment in the weld seam. A complementary system to monitor the airborne acoustic signals of the process is under development and the experimental results for defining the acoustic pattern of welding defects are presented.

  9. Real-Time Measurement of Width and Height of Weld Beads in GMAW Processes.

    PubMed

    Pinto-Lopera, Jesús Emilio; S T Motta, José Mauricio; Absi Alfaro, Sadek Crisostomo

    2016-09-15

    Associated to the weld quality, the weld bead geometry is one of the most important parameters in welding processes. It is a significant requirement in a welding project, especially in automatic welding systems where a specific width, height, or penetration of weld bead is needed. This paper presents a novel technique for real-time measuring of the width and height of weld beads in gas metal arc welding (GMAW) using a single high-speed camera and a long-pass optical filter in a passive vision system. The measuring method is based on digital image processing techniques and the image calibration process is based on projective transformations. The measurement process takes less than 3 milliseconds per image, which allows a transfer rate of more than 300 frames per second. The proposed methodology can be used in any metal transfer mode of a gas metal arc welding process and does not have occlusion problems. The responses of the measurement system, presented here, are in a good agreement with off-line data collected by a common laser-based 3D scanner. Each measurement is compare using a statistical Welch's t-test of the null hypothesis, which, in any case, does not exceed the threshold of significance level α = 0.01, validating the results and the performance of the proposed vision system.

  10. Real-Time Measurement of Width and Height of Weld Beads in GMAW Processes

    PubMed Central

    Pinto-Lopera, Jesús Emilio; S. T. Motta, José Mauricio; Absi Alfaro, Sadek Crisostomo

    2016-01-01

    Associated to the weld quality, the weld bead geometry is one of the most important parameters in welding processes. It is a significant requirement in a welding project, especially in automatic welding systems where a specific width, height, or penetration of weld bead is needed. This paper presents a novel technique for real-time measuring of the width and height of weld beads in gas metal arc welding (GMAW) using a single high-speed camera and a long-pass optical filter in a passive vision system. The measuring method is based on digital image processing techniques and the image calibration process is based on projective transformations. The measurement process takes less than 3 milliseconds per image, which allows a transfer rate of more than 300 frames per second. The proposed methodology can be used in any metal transfer mode of a gas metal arc welding process and does not have occlusion problems. The responses of the measurement system, presented here, are in a good agreement with off-line data collected by a common laser-based 3D scanner. Each measurement is compare using a statistical Welch’s t-test of the null hypothesis, which, in any case, does not exceed the threshold of significance level α = 0.01, validating the results and the performance of the proposed vision system. PMID:27649198

  11. Real time simulation of the retina allowing visualization of each processing stage

    SciTech Connect

    Teeters, J.L.; Werblin, F.

    1990-03-01

    Our retina computes to let us see, but can we see our retina compute? Until now, the answer has been `no` because the unconscious nature of the processing hides it from our view. Here we overcome the barrier of our closeness and describe what (to our knowledge) is the first method of seeing computations performed throughout the retina. This is achieved by using neurophysical data to construct a model of the retina, and using a special purpose image processing computer (PIPE) to implement the model in real time. Processing in the model is organized into stages corresponding to computations performed by each retinal cell type. The final stage is the formation of the transient (change detecting) ganglion cell response. A CCD camera forms the input image and the activity of any retinal cell type layer is the output which is displayed on a TV monitor. By changing the retina cell type driving the monitor, the progressive transformations of the image occurring in each stage of retina processing can be observed. The simulations demonstrate several phenomena including the slight blurring of the image caused by coupling between receptors, the relatively slow response to change and further blurring of the image by horizontal cells, the enhancement of moving edges by the bipolar cells, the separation of information flow into On and Off components, change detection in amacrine cells and the lateral inhibition to ganglion cells. Because the retina is the first stage of all biological vision systems, this processing may be useful for machine vision.

  12. Real time simulation of the retina allowing visualization of each processing stage

    SciTech Connect

    Teeters, J.L. ); Werblin, F. )

    1990-03-01

    Our retina computes to let us see, but can we see our retina compute Until now, the answer has been no' because the unconscious nature of the processing hides it from our view. Here we overcome the barrier of our closeness and describe what (to our knowledge) is the first method of seeing computations performed throughout the retina. This is achieved by using neurophysical data to construct a model of the retina, and using a special purpose image processing computer (PIPE) to implement the model in real time. Processing in the model is organized into stages corresponding to computations performed by each retinal cell type. The final stage is the formation of the transient (change detecting) ganglion cell response. A CCD camera forms the input image and the activity of any retinal cell type layer is the output which is displayed on a TV monitor. By changing the retina cell type driving the monitor, the progressive transformations of the image occurring in each stage of retina processing can be observed. The simulations demonstrate several phenomena including the slight blurring of the image caused by coupling between receptors, the relatively slow response to change and further blurring of the image by horizontal cells, the enhancement of moving edges by the bipolar cells, the separation of information flow into On and Off components, change detection in amacrine cells and the lateral inhibition to ganglion cells. Because the retina is the first stage of all biological vision systems, this processing may be useful for machine vision.

  13. Closed-loop pulsed helium ionization detector

    DOEpatents

    Ramsey, Roswitha S.; Todd, Richard A.

    1987-01-01

    A helium ionization detector for gas chromatography is operated in a constant current, pulse-modulated mode by configuring the detector, electrometer and a high voltage pulser in a closed-loop control system. The detector current is maintained at a fixed level by varying the frequency of fixed-width, high-voltage bias pulses applied to the detector. An output signal proportional to the pulse frequency is produced which is indicative of the charge collected for a detected species.

  14. Real-time simulation of the retina allowing visualization of each processing stage

    NASA Astrophysics Data System (ADS)

    Teeters, Jeffrey L.; Werblin, Frank S.

    1991-08-01

    The retina computes to let us see, but can we see the retina compute? Until now, the answer has been no, because the unconscious nature of the processing hides it from our view. Here the authors describe a method of seeing computations performed throughout the retina. This is achieved by using neurophysiological data to construct a model of the retina, and using a special-purpose image processing computer (PIPE) to implement the model in real time. Processing in the model is organized into stages corresponding to computations performed by each retinal cell type. The final stage is the transient (change detecting) ganglion cell. A CCD camera forms the input image, and the activity of a selected retinal cell type is the output which is displayed on a TV monitor. By changing the retina cell driving the monitor, the progressive transformations of the image by the retina can be observed. These simulations demonstrate the ubiquitous presence of temporal and spatial variations in the patterns of activity generated by the retina which are fed into the brain. The dynamical aspects make these patterns very different from those generated by the common DOG (Difference of Gaussian) model of receptive field. Because the retina is so successful in biological vision systems, the processing described here may be useful in machine vision.

  15. Fiber Bragg grating sensors for real-time monitoring of evacuation process

    NASA Astrophysics Data System (ADS)

    Guru Prasad, A. S.; Hegde, Gopalkrishna M.; Asokan, S.

    2009-12-01

    Fiber bragg grating (FBG) sensors have been widely used for number of sensing applications like temperature, pressure, acousto-ultrasonic, static and dynamic strain, refractive index change measurements and so on. Present work demonstrates the use of FBG sensors in in-situ measurement of vacuum process with simultaneous leak detection capability. Experiments were conducted in a bell jar vacuum chamber facilitated with conventional Pirani gauge for vacuum measurement. Three different experiments have been conducted to validate the performance of FBG sensor in monitoring vacuum creating process and air bleeding. The preliminary results of FBG sensors in vacuum monitoring have been compared with that of commercial Pirani gauge sensor. This novel technique offers a simple alternative to conventional method for real time monitoring of evacuation process. Proposed FBG based vacuum sensor has potential applications in vacuum systems involving hazardous environment such as chemical and gas plants, automobile industries, aeronautical establishments and leak monitoring in process industries, where the electrical or MEMS based sensors are prone to explosion and corrosion.

  16. Fiber Bragg grating sensors for real-time monitoring of evacuation process

    NASA Astrophysics Data System (ADS)

    Guru Prasad, A. S.; Hegde, Gopalkrishna M.; Asokan, S.

    2010-03-01

    Fiber bragg grating (FBG) sensors have been widely used for number of sensing applications like temperature, pressure, acousto-ultrasonic, static and dynamic strain, refractive index change measurements and so on. Present work demonstrates the use of FBG sensors in in-situ measurement of vacuum process with simultaneous leak detection capability. Experiments were conducted in a bell jar vacuum chamber facilitated with conventional Pirani gauge for vacuum measurement. Three different experiments have been conducted to validate the performance of FBG sensor in monitoring vacuum creating process and air bleeding. The preliminary results of FBG sensors in vacuum monitoring have been compared with that of commercial Pirani gauge sensor. This novel technique offers a simple alternative to conventional method for real time monitoring of evacuation process. Proposed FBG based vacuum sensor has potential applications in vacuum systems involving hazardous environment such as chemical and gas plants, automobile industries, aeronautical establishments and leak monitoring in process industries, where the electrical or MEMS based sensors are prone to explosion and corrosion.

  17. Whisper: Tracing the Spatiotemporal Process of Information Diffusion in Real Time.

    PubMed

    Cao, Nan; Lin, Yu-Ru; Sun, Xiaohua; Lazer, D; Liu, Shixia; Qu, Huamin

    2012-12-01

    When and where is an idea dispersed? Social media, like Twitter, has been increasingly used for exchanging information, opinions and emotions about events that are happening across the world. Here we propose a novel visualization design, "Whisper", for tracing the process of information diffusion in social media in real time. Our design highlights three major characteristics of diffusion processes in social media: the temporal trend, social-spatial extent, and community response of a topic of interest. Such social, spatiotemporal processes are conveyed based on a sunflower metaphor whose seeds are often dispersed far away. In Whisper, we summarize the collective responses of communities on a given topic based on how tweets were retweeted by groups of users, through representing the sentiments extracted from the tweets, and tracing the pathways of retweets on a spatial hierarchical layout. We use an efficient flux line-drawing algorithm to trace multiple pathways so the temporal and spatial patterns can be identified even for a bursty event. A focused diffusion series highlights key roles such as opinion leaders in the diffusion process. We demonstrate how our design facilitates the understanding of when and where a piece of information is dispersed and what are the social responses of the crowd, for large-scale events including political campaigns and natural disasters. Initial feedback from domain experts suggests promising use for today's information consumption and dispersion in the wild.

  18. Real-time SHVC software decoding with multi-threaded parallel processing

    NASA Astrophysics Data System (ADS)

    Gudumasu, Srinivas; He, Yuwen; Ye, Yan; He, Yong; Ryu, Eun-Seok; Dong, Jie; Xiu, Xiaoyu

    2014-09-01

    This paper proposes a parallel decoding framework for scalable HEVC (SHVC). Various optimization technologies are implemented on the basis of SHVC reference software SHM-2.0 to achieve real-time decoding speed for the two layer spatial scalability configuration. SHVC decoder complexity is analyzed with profiling information. The decoding process at each layer and the up-sampling process are designed in parallel and scheduled by a high level application task manager. Within each layer, multi-threaded decoding is applied to accelerate the layer decoding speed. Entropy decoding, reconstruction, and in-loop processing are pipeline designed with multiple threads based on groups of coding tree units (CTU). A group of CTUs is treated as a processing unit in each pipeline stage to achieve a better trade-off between parallelism and synchronization. Motion compensation, inverse quantization, and inverse transform modules are further optimized with SSE4 SIMD instructions. Simulations on a desktop with an Intel i7 processor 2600 running at 3.4 GHz show that the parallel SHVC software decoder is able to decode 1080p spatial 2x at up to 60 fps (frames per second) and 1080p spatial 1.5x at up to 50 fps for those bitstreams generated with SHVC common test conditions in the JCT-VC standardization group. The decoding performance at various bitrates with different optimization technologies and different numbers of threads are compared in terms of decoding speed and resource usage, including processor and memory.

  19. Closed Loop System Identification with Genetic Algorithms

    NASA Technical Reports Server (NTRS)

    Whorton, Mark S.

    2004-01-01

    High performance control design for a flexible space structure is challenging since high fidelity plant models are di.cult to obtain a priori. Uncertainty in the control design models typically require a very robust, low performance control design which must be tuned on-orbit to achieve the required performance. Closed loop system identi.cation is often required to obtain a multivariable open loop plant model based on closed-loop response data. In order to provide an accurate initial plant model to guarantee convergence for standard local optimization methods, this paper presents a global parameter optimization method using genetic algorithms. A minimal representation of the state space dynamics is employed to mitigate the non-uniqueness and over-parameterization of general state space realizations. This control-relevant system identi.cation procedure stresses the joint nature of the system identi.cation and control design problem by seeking to obtain a model that minimizes the di.erence between the predicted and actual closed-loop performance.

  20. Feasibility of closed-loop insulin delivery in type 2 diabetes: a randomized controlled study.

    PubMed

    Kumareswaran, Kavita; Thabit, Hood; Leelarathna, Lalantha; Caldwell, Karen; Elleri, Daniela; Allen, Janet M; Nodale, Marianna; Wilinska, Malgorzata E; Evans, Mark L; Hovorka, Roman

    2014-01-01

    Closed-loop insulin delivery offers a promising treatment option, but to date, it has only been evaluated in type 1 diabetes. Our aim was to evaluate the feasibility of fully closed-loop subcutaneous insulin delivery in insulin-naïve patients with type 2 diabetes. Twelve subjects (seven males, age 57.2 years, BMI 30.5 kg/m2) with noninsulin-treated type 2 diabetes (HbA1c 8.4% [68 mmol/mol], diabetes duration 7.6 years) underwent two 24-h visits (closed-loop and control) in a randomized crossover design. During closed-loop visits, the subjects' routine diabetes therapy was replaced with model predictive control algorithm-driven subcutaneous insulin pump delivery based on real-time continuous glucose monitoring. Meals were unannounced, and no additional insulin was administered for carbohydrates consumed. During control visits, the usual diabetes regimen was continued (metformin 92%, sulfonylureas 58%, dipeptidyl peptidase-4 inhibitors 33%). On both visits, subjects consumed matched 50- to 80-g carbohydrate meals and optional 15-g carbohydrate snacks and remained largely sedentary. Plasma glucose measurements evaluated closed-loop performance. Compared with conventional therapy, 24 h of closed-loop insulin delivery increased overall the median time in target plasma glucose (3.9-8.0 mmol/L) from 24 to 40% (P = 0.016), despite sensor under-reading by a median of 1.2 mmol/L. The benefit of the closed-loop system was more prominent overnight, with greater time in target glucose (median 78 vs. 35%; P = 0.041) and less time in hyperglycemia (22 vs. 65%; P = 0.041). There was no hypoglycemia during either intervention. A closed-loop system without meal announcement and using subcutaneous insulin delivery in insulin-naïve patients with type 2 diabetes appears feasible and safe. Improvement in postprandial glucose control may require further optimization of system performance.

  1. A Closed-Loop Hardware Simulation of Decentralized Satellite Formation Control

    NASA Technical Reports Server (NTRS)

    Ebimuma, Takuji; Lightsey, E. Glenn; Baur, Frank (Technical Monitor)

    2002-01-01

    In recent years, there has been significant interest in the use of formation flying spacecraft for a variety of earth and space science missions. Formation flying may provide smaller and cheaper satellites that, working together, have more capability than larger and more expensive satellites. Several decentralized architectures have been proposed for autonomous establishment and maintenance of satellite formations. In such architectures, each satellite cooperatively maintains the shape of the formation without a central supervisor, and processing only local measurement information. The Global Positioning System (GPS) sensors are ideally suited to provide such local position and velocity measurements to the individual satellites. An investigation of the feasibility of a decentralized approach to satellite formation flying was originally presented by Carpenter. He extended a decentralized linear-quadratic-Gaussian (LQG) framework proposed by Speyer in a fashion similar to an extended Kalman filter (EKE) which processed GPS position fix solutions. The new decentralized LQG architecture was demonstrated in a numerical simulation for a realistic scenario that is similar to missions that have been proposed by NASA and the U.S. Air Force. Another decentralized architecture was proposed by Park et al. using carrier differential-phase GPS (CDGPS). Recently, Busse et al demonstrated the decentralized CDGPS architecture in a hardware-in-the-loop simulation on the Formation Flying TestBed (FFTB) at Goddard Space Flight Center (GSFC), which features two Spirent Cox 16 channel GPS signal generator. Although representing a step forward by utilizing GPS signal simulators for a spacecraft formation flying simulation, only an open-loop performance, in which no maneuvers were executed based on the real-time state estimates, was considered. In this research, hardware experimentation has been extended to include closed-loop integrated guidance and navigation of multiple spacecraft

  2. Real-Time Processing System for the JET Hard X-Ray and Gamma-Ray Profile Monitor Enhancement

    NASA Astrophysics Data System (ADS)

    Fernandes, Ana M.; Pereira, Rita C.; Neto, André; Valcárcel, Daniel F.; Alves, Diogo; Sousa, Jorge; Carvalho, Bernardo B.; Kiptily, Vasily; Syme, Brian; Blanchard, Patrick; Murari, Andrea; Correia, Carlos M. B. A.; Varandas, Carlos A. F.; Gonçalves, Bruno

    2014-06-01

    The Joint European Torus (JET) is currently undertaking an enhancement program which includes tests of relevant diagnostics with real-time processing capabilities for the International Thermonuclear Experimental Reactor (ITER). Accordingly, a new real-time processing system was developed and installed at JET for the gamma-ray and hard X-ray profile monitor diagnostic. The new system is connected to 19 CsI(Tl) photodiodes in order to obtain the line-integrated profiles of the gamma-ray and hard X-ray emissions. Moreover, it was designed to overcome the former data acquisition (DAQ) limitations while exploiting the required real-time features. The new DAQ hardware, based on the Advanced Telecommunication Computer Architecture (ATCA) standard, includes reconfigurable digitizer modules with embedded field-programmable gate array (FPGA) devices capable of acquiring and simultaneously processing data in real-time from the 19 detectors. A suitable algorithm was developed and implemented in the FPGAs, which are able to deliver the corresponding energy of the acquired pulses. The processed data is sent periodically, during the discharge, through the JET real-time network and stored in the JET scientific databases at the end of the pulse. The interface between the ATCA digitizers, the JET control and data acquisition system (CODAS), and the JET real-time network is provided by the Multithreaded Application Real-Time executor (MARTe). The work developed allowed attaining two of the major milestones required by next fusion devices: the ability to process and simultaneously supply high volume data rates in real-time.

  3. Real-time energy measurement of high repetition rate ultrashort laser pulses using pulse integration and FPGA processing.

    PubMed

    Tang, Qi-Jie; Yang, Dong-Xu; Wang, Jian; Feng, Yi; Zhang, Hong-Fei; Chen, Teng-Yun

    2016-11-01

    Real-time energy measurement using pulse integration method for high repetition rate ultrashort laser pulses based on FPGA (Field-Programmable Gate Array) and high-speed pipeline ADC (Analog-to-Digital Convertor) is introduced in this paper. There are two parts contained in this method: pulse integration and real-time data processing. The pulse integration circuit will convert the pulse to the step type signals which are linear to the laser pulse energy. Through the real-time data processing part, the amplitude of the step signals will be obtained by ADC sampling and conducting calculation in real time in FPGA. The test result shows that the method with good linearity (4.770%) and without pulse measurement missing is suitable for ultrashort laser pulses with high repetition rate up to 100 MHz.

  4. Real-time energy measurement of high repetition rate ultrashort laser pulses using pulse integration and FPGA processing

    NASA Astrophysics Data System (ADS)

    Tang, Qi-jie; Yang, Dong-xu; Wang, Jian; Feng, Yi; Zhang, Hong-fei; Chen, Teng-yun

    2016-11-01

    Real-time energy measurement using pulse integration method for high repetition rate ultrashort laser pulses based on FPGA (Field-Programmable Gate Array) and high-speed pipeline ADC (Analog-to-Digital Convertor) is introduced in this paper. There are two parts contained in this method: pulse integration and real-time data processing. The pulse integration circuit will convert the pulse to the step type signals which are linear to the laser pulse energy. Through the real-time data processing part, the amplitude of the step signals will be obtained by ADC sampling and conducting calculation in real time in FPGA. The test result shows that the method with good linearity (4.770%) and without pulse measurement missing is suitable for ultrashort laser pulses with high repetition rate up to 100 MHz.

  5. Architectures and design techniques for real-time image processing ICs

    SciTech Connect

    Ruetz, P.A.

    1986-01-01

    A set of 8 chips, which perform real-time image processing tasks, was designed and fabricated with a 4..mu.. MNOS technology. The chips include: a 3 x 3 linear convolver, a 3 x 3 sorting filter, a 7 x 7 logical convolver, a contour tracer, a feature extractor, a look-up table ROM, and two post processors for the linear convolver. All chips were designed using architectures dedicated to the particular image processing tasks to be performed. The image processing circuits operate on 10-MHz video data (512 x 512 pixel images). The design time for the chips was kept to 1.5 man years by re-using hardware and, in addition, utilizing and developing some appropriate CAD tools. ROM generators and a data-path generator were developed to reduce the circuit design time. An image-recognition system was built with these custom chips that can recognize two dimensional objects that are characterized by their closed outer contours. The complete system is controlled by a SUN work station and operates at rates up to 15 frame/Sec. The recognition system achieved a 97% recognition rate for 8 objects over a wide range of orientation and size variations and a 100% recognition rate without size variations.

  6. Near Real-Time Collection, Processing, and Publication of Beach Morphology and Oceanographic LIDAR Data

    NASA Astrophysics Data System (ADS)

    Dyer, T.; Brodie, K. L.; Spore, N.

    2016-02-01

    Modern LIDAR systems, while capable of providing highly accurate and dense datasets, introduce significant challenges in data processing and end-user accessibility. At the United States Army Corps of Engineers Field Research Facility in Duck, North Carolina, we have developed a stationary LIDAR tower for the continuous monitoring of the ocean, beach, and foredune, as well as an automated workflow capable of providing scientific data products from the LIDAR scanner in near real-time through an online data portal. The LIDAR performs hourly scans, taking approximately 50 minutes to complete and producing datasets on the order of 1GB. Processing of the LIDAR data includes coordinate transformations, data rectification and coregistration, filtering to remove noise and unwanted objects, gridding, and time-series analysis to generate products for use by end-users. Examples of these products include water levels and significant wave heights, virtual wave gauge time-series and FFTs, wave runup, foreshore elevations and slopes, and bare earth DEMs. Immediately after processing, data products are combined with ISO compliant metadata and stored using the NetCDF-4 file format, making them easily discoverable through a web portal which provides an interactive map that allows users to explore datasets both spatially and temporally. End-users can download datasets in user-defined time intervals, which can be used, for example, as forcing or validation parameters in numerical models. Funded by the USACE Coastal Ocean Data Systems Program.

  7. Real-time observation of cascaded electronic relaxation processes in p-Fluorotoluene

    NASA Astrophysics Data System (ADS)

    Hao, Qiaoli; Deng, Xulan; Long, Jinyou; Wang, Yanmei; Abulimiti, Bumaliya; Zhang, Bing

    2017-08-01

    Ultrafast electronic relaxation processes following two photoexcitation of 400 nm in p-Fluorotoluene (pFT) have been investigated utilizing time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Cascaded electronic relaxation processes started from the electronically excited S2 state are directly imaged in real time and well characterized by two distinct time constants of 85 ± 10 fs and 2.4 ± 0.3 ps. The rapid component corresponds to the lifetime of the initially excited S2 state, including the structure relaxation from the Franck-Condon region to the conical intersection of S2/S1 and the subsequent internal conversion to the highly excited S1 state. While, the slower relaxation constant is attributed to the further internal conversion to the high levels of S0 from the secondarily populated S1 locating in the channel three region. Moreover, dynamical differences with benzene and toluene of analogous structures, including, specifically, the slightly slower relaxation rate of S2 and the evidently faster decay of S1, are also presented and tentatively interpreted as the substituent effects. In addition, photoelectron kinetic energy and angular distributions reveal the feature of accidental resonances with low-lying Rydberg states (the 3p, 4s and 4p states) during the multi-photon ionization process, providing totally unexpected but very interesting information for pFT.

  8. Dynamic Engagement of Cognitive Control Modulates Recovery From Misinterpretation During Real-Time Language Processing.

    PubMed

    Hsu, Nina S; Novick, Jared M

    2016-04-01

    Speech unfolds swiftly, yet listeners keep pace by rapidly assigning meaning to what they hear. Sometimes, though, initial interpretations turn out to be wrong. How do listeners revise misinterpretations of language input moment by moment to avoid comprehension errors? Cognitive control may play a role by detecting when processing has gone awry and then initiating behavioral adjustments accordingly. However, no research to date has investigated a cause-and-effect interplay between cognitive-control engagement and the overriding of erroneous interpretations in real time. Using a novel cross-task paradigm, we showed that Stroop-conflict detection, which mobilizes cognitive-control procedures, subsequently facilitates listeners' incremental processing of temporarily ambiguous spoken instructions that induce brief misinterpretation. When instructions followed incongruent Stroop items, compared with congruent Stroop items, listeners' eye movements to objects in a scene reflected more transient consideration of the false interpretation and earlier recovery of the correct one. Comprehension errors also decreased. Cognitive-control engagement therefore accelerates sentence-reinterpretation processes, even as linguistic input is still unfolding. © The Author(s) 2016.

  9. Dynamic engagement of cognitive control modulates recovery from misinterpretation during real-time language processing

    PubMed Central

    Hsu, Nina S.; Novick, Jared M.

    2016-01-01

    Speech unfolds swiftly, yet listeners keep pace by rapidly assigning meaning to what they hear. Sometimes though, initial interpretations turn out wrong. How do listeners revise misinterpretations of language input moment-by-moment, to avoid comprehension errors? Cognitive control may play a role by detecting when processing has gone awry, and then initiating behavioral adjustments accordingly. However, no research has investigated a cause-and-effect interplay between cognitive control engagement and overriding erroneous interpretations in real-time. Using a novel cross-task paradigm, we show that Stroop-conflict detection, which mobilizes cognitive control procedures, subsequently facilitates listeners’ incremental processing of temporarily ambiguous spoken instructions that induce brief misinterpretation. When instructions followed Stroop-incongruent versus-congruent items, listeners’ eye-movements to objects in a scene reflected more transient consideration of the false interpretation and earlier recovery of the correct one. Comprehension errors also decreased. Cognitive control engagement therefore accelerates sentence re-interpretation processes, even as linguistic input is still unfolding. PMID:26957521

  10. Study of building materials impregnation processes by quasi-real-time neutron radiography

    NASA Astrophysics Data System (ADS)

    Nemec, T.; Rant, J.; Apih, V.; Glumac, B.

    1999-11-01

    Neutron radiography (NR) is a useful non-destructive method for determination of hydrogen content in various building and technical materials. Monitoring of transport processes of moisture and hydrogenous liquids in porous building materials is enabled by fast, quasi-real-time NR methods based on novel imaging plate neutron detectors (IP-NDs). Hydrogen content in the samples is determined by quantitative analysis of measured profiles of neutron attenuation in the samples. Detailed description of quantitative NR method is presented by the authors in another accompanying contribution at this conference. Deterioration of building materials is originated by different processes that all require presence of water therefore it is essential to limit or prevent the transport of water through the porous material. In this presentation, results of a study of clay brick impregnation by silicone based hydrophobic agents will be presented. Quantitative results obtained by NR imaging successfully explained the processes that occur during the impregnation of porous materials. Efficiency of hydrophobic treatment was quantitatively evaluated.

  11. Similarity Metrics for Closed Loop Dynamic Systems

    NASA Technical Reports Server (NTRS)

    Whorton, Mark S.; Yang, Lee C.; Bedrossian, Naz; Hall, Robert A.

    2008-01-01

    To what extent and in what ways can two closed-loop dynamic systems be said to be "similar?" This question arises in a wide range of dynamic systems modeling and control system design applications. For example, bounds on error models are fundamental to the controller optimization with modern control design methods. Metrics such as the structured singular value are direct measures of the degree to which properties such as stability or performance are maintained in the presence of specified uncertainties or variations in the plant model. Similarly, controls-related areas such as system identification, model reduction, and experimental model validation employ measures of similarity between multiple realizations of a dynamic system. Each area has its tools and approaches, with each tool more or less suited for one application or the other. Similarity in the context of closed-loop model validation via flight test is subtly different from error measures in the typical controls oriented application. Whereas similarity in a robust control context relates to plant variation and the attendant affect on stability and performance, in this context similarity metrics are sought that assess the relevance of a dynamic system test for the purpose of validating the stability and performance of a "similar" dynamic system. Similarity in the context of system identification is much more relevant than are robust control analogies in that errors between one dynamic system (the test article) and another (the nominal "design" model) are sought for the purpose of bounding the validity of a model for control design and analysis. Yet system identification typically involves open-loop plant models which are independent of the control system (with the exception of limited developments in closed-loop system identification which is nonetheless focused on obtaining open-loop plant models from closed-loop data). Moreover the objectives of system identification are not the same as a flight test and

  12. Extended kinetic model of real-time polymerase chain reaction process

    NASA Astrophysics Data System (ADS)

    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.

  13. The MODIS Rapid Response Project: Near-Real-Time Processing for Fire Monitoring and Other Applications

    NASA Astrophysics Data System (ADS)

    Descloitres, J.; Justice, C.; Sohlberg, R.; Giglio, L.; Schmaltz, J.; Seaton, J.; Davies, D.; Anyamba, A.; Hansen, M.; Carroll, M.; Sullivan, M.

    2003-12-01

    The Moderate-resolution Imaging Spectroradiometer (MODIS) instrument on board the Terra and Aqua satellites offers an unprecedented combination of daily spatial coverage, spatial resolution, and spectral characteristics. These capabilities make MODIS ideal to observe a variety of rapid events: active fires, floods, smoke transport, dust storms, severe storms, iceberg calving, and volcanic eruptions. The MODIS Rapid Response System (http://rapidfire.sci.gsfc.nasa.gov) was developed at NASA's Goddard Space Flight Center to provide a rapid response to those events, with initial emphasis on active fire detection and 250m-resolution imagery. MODIS data for most of the Earth's land surface is processed just a few hours after data acquisition. A collaboration between NASA, the University of Maryland and the U.S.D.A. Forest Service has been developed to provide fire information derived from MODIS to federal fire managers. Active fire locations in the conterminous United States are produced by the MODIS Rapid Response System and communicated to the Forest Service within a few minutes of production. The MODIS Rapid Response processing was also adapted to Direct Broadcast to reduce the product turn-around to just minutes after data acquisition regionally. MODIS active fire locations are used by the Forest Service to generate regional fire maps over the United States, updated twice daily and provided to the fire managers to help them allocate firefighting resources. Active fire locations are also distributed in near-real-time to the Global Observation of Forest Cover (G.O.F.C.) user community through a web interface integrating MODIS active fire locations and Geographic Information System (G.I.S.) datasets. The suite of MODIS rapid fire products is currently being complemented with a Smoke Index product and a Burned Area product that will represent two new key tools available to the fire community. Finally a new collaboration with the U.S.D.A. Foreign Agricultural Service was

  14. Low-complexity image processing for real-time detection of neonatal clonic seizures.

    PubMed

    Ntonfo, Guy Mathurin Kouamou; Ferrari, Gianluigi; Raheli, Riccardo; Pisani, Francesco

    2012-05-01

    In this paper, we consider a novel low-complexity real-time image-processing-based approach to the detection of neonatal clonic seizures. Our approach is based on the extraction, from a video of a newborn, of an average luminance signal representative of the body movements. Since clonic seizures are characterized by periodic movements of parts of the body (e.g., the limbs), by evaluating the periodicity of the extracted average luminance signal it is possible to detect the presence of a clonic seizure. The periodicity is investigated, through a hybrid autocorrelation-Yin estimation technique, on a per-window basis, where a time window is defined as a sequence of consecutive video frames. While processing is first carried out on a single window basis, we extend our approach to interlaced windows. The performance of the proposed detection algorithm is investigated, in terms of sensitivity and specificity, through receiver operating characteristic curves, considering video recordings of newborns affected by neonatal seizures.

  15. The Swedish National Seismic Network: real-time processing of data from 60 broadband stations

    NASA Astrophysics Data System (ADS)

    Bodvarsson, R.; Erlendsson, P.; Lund, B.; Shomali, H.; Tryggvason, A.

    2009-04-01

    The Swedish National Seismic Network (SNSN) has recently finished the expansion to 60 high-gain broadband seismic stations, covering the entire country from south to north with a station spacing of approximately 100 km. During the last year the SNSN has also moved from using segmented data transferred via dial-up telephone land-lines to continuous data transmission over broadband mobile telecommunication networks. In this talk we will share some of our experiences with mobile telecommunication data transfer and then concentrate on how the data is processed in real-time at the SNSN data center in Uppsala. As the data arrives in Uppsala (currently using Guralp's Scream software) it is placed in a shared memory ring-buffer system. The system not only allows multiple copies of individual data streams in separate buffers but also streams of derived data, such as amplitude based energy, data deconvolved with the instrument response or detections. This buffer system allows easy access to suitable data for the application software, such as detectors, location and focal mechanism algorithms. One such application which is currently running is a magnitude estimator for energy duration magnitudes of large events. As of today only data from the SNSN stations are processed but in the near future data from stations in Finland, Denmark and Norway will be included in order to enhance the regional coverage of the location system. Additionally, stations from around the globe will be incorporated to allow fast estimates of location and magnitude of large teleseismic events.

  16. Real-Time Data Processing in the muon system of the D0 detector.

    SciTech Connect

    Neeti Parashar et al.

    2001-07-03

    This paper presents a real-time application of the 16-bit fixed point Digital Signal Processors (DSPs), in the Muon System of the D0 detector located at the Fermilab Tevatron, presently the world's highest-energy hadron collider. As part of the Upgrade for a run beginning in the year 2000, the system is required to process data at an input event rate of 10 KHz without incurring significant deadtime in readout. The ADSP21csp01 processor has high I/O bandwidth, single cycle instruction execution and fast task switching support to provide efficient multisignal processing. The processor's internal memory consists of 4K words of Program Memory and 4K words of Data Memory. In addition there is an external memory of 32K words for general event buffering and 16K words of Dual port Memory for input data queuing. This DSP fulfills the requirement of the Muon subdetector systems for data readout. All error handling, buffering, formatting and transferring of the data to the various trigger levels of the data acquisition system is done in software. The algorithms developed for the system complete these tasks in about 20 {micro}s per event.

  17. Real-time signal processing of accelerometer data for wearable medical patient monitoring devices.

    PubMed

    Van Wieringen, Matt; Eklund, J

    2008-01-01

    Elderly and other people who live at home but required some physical assistance to do so are often more susceptible injury causing falls in and around their place of residence. In the event that a fall does occur, as a direct result of a previous medical condition or the fall itself, these people are typically less likely to be able to seek timely medical help without assistance. The goal of this research is to develop a wearable sensor device that uses an accelerometer for monitoring the movement of the person to detect falls after they have occurred in order to enable timely medical assistance. The data coming from the accelerometer is processed in real-time in the device and sent to a remote monitoring station where operators can attempt to make contact with the person and/or notify medical personnel of the situation. The ADXL330 accelerometer is contained within a Nintendo WiiMote controller, which forms the basis of the wearable medical sensor. The accelerometer data can then be sent via Bluetooth connection and processed by a local gateway processor. If a fall is detected, the gateway will then contact a remote monitoring station, on a cellular network, for example, via satellite, and/or through a hardwired phone or Internet connection. To detect the occurrence of ta fall, the accelerometer data is passed through a matched filter and the data is compared to benchmark analysis data that will define the conditions that represents the occurrence of a fall.

  18. Lysosome triggered near-infrared fluorescence imaging of cellular trafficking processes in real time

    PubMed Central

    Grossi, Marco; Morgunova, Marina; Cheung, Shane; Scholz, Dimitri; Conroy, Emer; Terrile, Marta; Panarella, Angela; Simpson, Jeremy C.; Gallagher, William M.; O'Shea, Donal F.

    2016-01-01

    Bioresponsive NIR-fluorophores offer the possibility for continual visualization of dynamic cellular processes with added potential for direct translation to in vivo imaging. Here we show the design, synthesis and lysosome-responsive emission properties of a new NIR fluorophore. The NIR fluorescent probe design differs from typical amine functionalized lysosomotropic stains with off/on fluorescence switching controlled by a reversible phenol/phenolate interconversion. Emission from the probe is shown to be highly selective for the lysosomes in co-imaging experiments using a HeLa cell line expressing the lysosomal-associated membrane protein 1 fused to green fluorescent protein. The responsive probe is capable of real-time continuous imaging of fundamental cellular processes such as endocytosis, lysosomal trafficking and efflux in 3D and 4D. The advantage of the NIR emission allows for direct translation to in vivo tumour imaging, which is successfully demonstrated using an MDA-MB-231 subcutaneous tumour model. This bioresponsive NIR fluorophore offers significant potential for use in live cellular and in vivo imaging, for which currently there is a deficit of suitable molecular fluorescent tools. PMID:26927507

  19. The role of parallelism in the real-time processing of anaphora

    PubMed Central

    Poirier, Josée; Walenski, Matthew; Shapiro, Lewis P.

    2012-01-01

    Parallelism effects refer to the facilitated processing of a target structure when it follows a similar, parallel structure. In coordination, a parallelism-related conjunction triggers the expectation that a second conjunct with the same structure as the first conjunct should occur. It has been proposed that parallelism effects reflect the use of the first structure as a template that guides the processing of the second. In this study, we examined the role of parallelism in real-time anaphora resolution by charting activation patterns in coordinated constructions containing anaphora, Verb-Phrase Ellipsis (VPE) and Noun-Phrase Traces (NP-traces). Specifically, we hypothesised that an expectation of parallelism would incite the parser to assume a structure similar to the first conjunct in the second, anaphora-containing conjunct. The speculation of a similar structure would result in early postulation of covert anaphora. Experiment 1 confirms that following a parallelism-related conjunction, first-conjunct material is activated in the second conjunct. Experiment 2 reveals that an NP-trace in the second conjunct is posited immediately where licensed, which is earlier than previously reported in the literature. In light of our findings, we propose an intricate relation between structural expectations and anaphor resolution. PMID:23741080

  20. Near Real Time VIIRS EDR Products Via Direct Broadcast Using the Community Satellite Processing Package (CSPP)

    NASA Astrophysics Data System (ADS)

    Cureton, G. P.; Mindock, S.; Martin, G.; Garcia, R.; Strabala, K.; Davies, J.; Bearson, N.; Gumley, L.; Huang, A.

    2014-12-01

    The Cooperative Institute for Meteorological Satellite Studies (CIMSS) has a long history of supporting the Direct Broadcast (DB) community for various sensors, recently with the International MODIS/AIRS Processing Package (IMAPP) for the NASA EOS polar orbiters Terra and Aqua. CIMSS has continued this effort into the NPP/JPSS (previously NPOESS) era with the development of the Community Satellite Processing Package (CSPP), supporting the VIIRS, CrIS and ATMS sensors on the Suomi National Polar-orbiting Partnership (Suomi NPP) spacecraft. Within CSPP, the Visible Infrared Imaging Radiometer Suite (VIIRS) Environmental Data Record (EDR) products are based on the NOAA Operational products as implemented by Raytheon in the Algorithm Development Library (ADL), packaged for use in a Direct Broadcast environment. Examples of near real time usage of various VIIRS EDR products are given, with a focus on products obtained using CSPP (which include the Cloud Mask, Active Fires, Aerosol Optical Thickness, Sea Surface Temperature, Surface Reflectance, Vegetation Index, Surface Type and Land Surface Temperature products).

  1. APNEA list mode data acquisition and real-time event processing

    SciTech Connect

    Hogle, R.A.; Miller, P.; Bramblett, R.L.

    1997-11-01

    The LMSC Active Passive Neutron Examinations and Assay (APNEA) Data Logger is a VME-based data acquisition system using commercial-off-the-shelf hardware with the application-specific software. It receives TTL inputs from eighty-eight {sup 3}He detector tubes and eight timing signals. Two data sets are generated concurrently for each acquisition session: (1) List Mode recording of all detector and timing signals, timestamped to 3 microsecond resolution; (2) Event Accumulations generated in real-time by counting events into short (tens of microseconds) and long (seconds) time bins following repetitive triggers. List Mode data sets can be post-processed to: (1) determine the optimum time bins for TRU assay of waste drums, (2) analyze a given data set in several ways to match different assay requirements and conditions and (3) confirm assay results by examining details of the raw data. Data Logger events are processed and timestamped by an array of 15 TMS320C40 DSPs and delivered to an embedded controller (PowerPC604) for interim disk storage. Three acquisition modes, corresponding to different trigger sources are provided. A standard network interface to a remote host system (Windows NT or SunOS) provides for system control, status, and transfer of previously acquired data. 6 figs.

  2. Preconditioning of real-time optical Wiener filters for array processing

    NASA Astrophysics Data System (ADS)

    Ghosh, Anjan; Paparao, Palacharla

    1992-07-01

    In adaptive array processors, a performance measure, such as mean square error or signal to noise ration, coverages to the optimum Wiener solution starting from an initial setting. The choice of adaptive algorithms to solve the Wiener filtering problem is mainly guided by the desired processing time. In an optical realization for direct calculation of the optimum weights the covariance matrix and vector for a Wiener filter are computed at a high speed on acousto-optic processors. The resulting linear system of equations can be solved on an iterative optical processor. The matrix and vector data should be recomputed in every iteration for better tracking and adaptation. This introduces variations in their values due to the time-varying jamming and interference noise and the optical errors and noise. Time variant steepest descent algorithm is a simple method that converges to the common solution. In this paper, we describe a real-time preconditioning technique for such nonstationary iterative methods. Preconditioning will progressively lower the condition number of each matrix in the sequence, thereby improving the convergence speed and accuracy of the solution. This preconditioning process involves matrix-matrix multiplications that can be performed at high speed on parallel optical processors. Results of simulations illustrate the superlinear convergence obtained from preconditioning.

  3. Advanced image processing and wavefront sensing with real-time phase diversity.

    PubMed

    Dolne, Jean J; Menicucci, Paul; Miccolis, David; Widen, Ken; Seiden, Harold; Vachss, Frederick; Schall, Harold

    2009-01-01

    This paper will describe a state-of-the-art approach to real-time wavefront sensing and image enhancement. It will explore Boeing's existing technology to realize a 50 Hz frame rate (with a path to 1 KHz and higher). At this higher rate, phase diversity will be readily applicable to compensate for distortions of large dynamic bandwidth such as those of the atmosphere. We will describe various challenges in aligning a two-camera phase diversity system. Such configurations make it almost impossible to process the captured images without additional upgrade in the algorithm to account for alignment errors. An example of an error is the relative misalignment of the two images, the "best-focus" and the diversity image, where it is extremely hard to maintain alignment to less than a fraction of 1 pixel. We will show that the algorithm performance increases dramatically when we account for these errors in the estimation process. Preliminary evaluation has assessed a National Imagery Interpretability Rating Scale increase of approximately 3 from the best-focus to the enhanced image. Such a performance improvement would greatly increase the operating range (or, equivalently, decrease the weight) of many optical systems.

  4. Why in situ, real-time characterization of thin film growth processes?

    SciTech Connect

    Auciello, O.; Krauss, A.R.

    1995-08-01

    Since thin-film growth occurs at the surface, the analytical methods should be highly surface-specific. although subsurface diffusion and chemical processes also affect film properties. Sampling depth and ambient-gas is compatibility are key factors which must be considered when choosing in situ probes of thin-film growth phenomena. In most cases, the sampling depth depends on the mean range of the exit species (ion, photon, or electron) in the sample. The techniques that are discussed in this issue of the MRS Bulletin (1) have been chosen because they may be used for in situ, real-time analysis of film-growth phenomena in vacuum and in the presence of ambient gases resulting either from the deposition process or as a requirement for the production of the desired chemical phase. A second criterion for inclusion is that the instrumentation be sufficiently compact and inexpensive to permit use as a dedicated tool in a thin-film deposition system.

  5. Real-time tracking data drive process improvements, even while ED volumes continue to climb.

    PubMed

    2012-06-01

    Christiana Hospital in Newark, DE, has been able to dramatically reduce length-of-stay in the ED by making use of data derived from a real-time location system (RTLS) that tracks the movements of patients, providers, and staff. Administrators say that while some efficiencies are gained from the system alone, most of the positive impact is derived from using the RTLS data to focus on specific processes and make refinements. Within one year of implementing the RTLS technology, LOS in the ED was reduced by 40 minutes for admitted patients and 18 to 20 minutes for the treated-and-released population. A work group focused on process improvements in the ED's fast track section reduced the average LOS from 2.5 hours to 60 minutes or less. Similarly, a work group focused on the ESI 3 population reduced the average treatment time for this population from 5 or 6 hours to 3.4 hours. Administrators say key steps toward a successful RTLS implementation are careful planning for how you want to use the technology, and alleviating staff concerns about why their movements are being tracked.

  6. An optimal open/closed-loop control method with application to a pre-stressed thin duralumin plate

    NASA Astrophysics Data System (ADS)

    Nadimpalli, Sruthi Raju

    The excessive vibrations of a pre-stressed duralumin plate, suppressed by a combination of open-loop and closed-loop controls, also known as open/closed-loop control, is studied in this thesis. The two primary steps involved in this process are: Step (I) with an assumption that the closed-loop control law is proportional, obtain the optimal open-loop control by direct minimization of the performance measure consisting of energy at terminal time and a penalty on open-loop control force via calculus of variations. If the performance measure also involves a penalty on closed-loop control effort then a Fourier based method is utilized. Step (II) the energy at terminal time is minimized numerically to obtain optimal values of feedback gains. The optimal closed-loop control gains obtained are used to describe the displacement and the velocity of open-loop, closed-loop and open/closed-loop controlled duralumin plate.

  7. Real-time reconstruction of sensitivity encoded radial magnetic resonance imaging using a graphics processing unit.

    PubMed

    Sørensen, Thomas Sangild; Atkinson, David; Schaeffter, Tobias; Hansen, Michael Schacht

    2009-12-01

    A barrier to the adoption of non-Cartesian parallel magnetic resonance imaging for real-time applications has been the times required for the image reconstructions. These times have exceeded the underlying acquisition time thus preventing real-time display of the acquired images. We present a reconstruction algorithm for commodity graphics hardware (GPUs) to enable real time reconstruction of sensitivity encoded radial imaging (radial SENSE). We demonstrate that a radial profile order based on the golden ratio facilitates reconstruction from an arbitrary number of profiles. This allows the temporal resolution to be adjusted on the fly. A user adaptable regularization term is also included and, particularly for highly undersampled data, used to interactively improve the reconstruction quality. Each reconstruction is fully self-contained from the profile stream, i.e., the required coil sensitivity profiles, sampling density compensation weights, regularization terms, and noise estimates are computed in real-time from the acquisition data itself. The reconstruction implementation is verified using a steady state free precession (SSFP) pulse sequence and quantitatively evaluated. Three applications are demonstrated; real-time imaging with real-time SENSE 1) or k- t SENSE 2) reconstructions, and 3) offline reconstruction with interactive adjustment of reconstruction settings.

  8. Accessible high performance computing solutions for near real-time image processing for time critical applications

    NASA Astrophysics Data System (ADS)

    Bielski, Conrad; Lemoine, Guido; Syryczynski, Jacek

    2009-09-01

    High Performance Computing (HPC) hardware solutions such as grid computing and General Processing on a Graphics Processing Unit (GPGPU) are now accessible to users with general computing needs. Grid computing infrastructures in the form of computing clusters or blades are becoming common place and GPGPU solutions that leverage the processing power of the video card are quickly being integrated into personal workstations. Our interest in these HPC technologies stems from the need to produce near real-time maps from a combination of pre- and post-event satellite imagery in support of post-disaster management. Faster processing provides a twofold gain in this situation: 1. critical information can be provided faster and 2. more elaborate automated processing can be performed prior to providing the critical information. In our particular case, we test the use of the PANTEX index which is based on analysis of image textural measures extracted using anisotropic, rotation-invariant GLCM statistics. The use of this index, applied in a moving window, has been shown to successfully identify built-up areas in remotely sensed imagery. Built-up index image masks are important input to the structuring of damage assessment interpretation because they help optimise the workload. The performance of computing the PANTEX workflow is compared on two different HPC hardware architectures: (1) a blade server with 4 blades, each having dual quad-core CPUs and (2) a CUDA enabled GPU workstation. The reference platform is a dual CPU-quad core workstation and the PANTEX workflow total computing time is measured. Furthermore, as part of a qualitative evaluation, the differences in setting up and configuring various hardware solutions and the related software coding effort is presented.

  9. Processing 3D flash LADAR point-clouds in real-time for flight applications

    NASA Astrophysics Data System (ADS)

    Craig, R.; Gravseth, I.; Earhart, R. P.; Bladt, J.; Barnhill, S.; Ruppert, L.; Centamore, C.

    2007-04-01

    Ball Aerospace & Technologies Corp. has demonstrated real-time processing of 3D imaging LADAR point-cloud data to produce the industry's first time-of-flight (TOF) 3D video capability. This capability is uniquely suited to the rigorous demands of space and airborne flight applications and holds great promise in the area of autonomous navigation. It will provide long-range, three dimensional video information to autonomous flight software or pilots for immediate use in rendezvous and docking, proximity operations, landing, surface vision systems, and automatic target recognition and tracking. This is enabled by our new generation of FPGA based "pixel-tube" processors, coprocessors and their associated algorithms which have led to a number of advancements in high-speed wavefront processing along with additional advances in dynamic camera control, and space laser designs based on Ball's CALIPSO LIDAR. This evolution in LADAR is made possible by moving the mechanical complexity required for a scanning system into the electronics, where production, integration, testing and life-cycle costs can be significantly reduced. This technique requires a state of the art TOF read-out integrated circuit (ROIC) attached to a sensor array to collect high resolution temporal data, which is then processed through FPGAs. The number of calculations required to process the data is greatly reduced thanks to the fact that all points are captured at the same time and thus correlated. This correlation allows extremely efficient FPGA processing. This capability has been demonstrated in prototype form at both Marshal Space Flight Center and Langley Research Center on targets that represent docking and landing scenarios. This report outlines many aspects of this work as well as aspects of our recent testing at Marshall's Flight Robotics Laboratory.

  10. Continuous-flow C. elegans fluorescence expression analysis with real-time image processing through microfluidics.

    PubMed

    Yan, Yuanjun; Boey, Daryl; Ng, Li Theng; Gruber, Jan; Bettiol, Andrew; Thakor, Nitish V; Chen, Chia-Hung

    2016-03-15

    The nematode Caenorhabditis elegans has become an essential model organism in neuroscience research because of its stereotyped anatomy, relevance to human biology, and capacity for genetic manipulation. To solve the intrinsic challenges associated with performing manual operations on C. elegans, many automated chip designs based on immobilization-imaging-release approaches have been proposed. These designs are prone to limitations such as the exertion of physical stress on the worms and limited throughput. In this work, a continuous-flow, high-throughput, automated C. elegans analyzer based on droplet encapsulation and real-time image processing was developed to analyze fluorescence expression in worms. To demonstrate its capabilities, two strains of C. elegans nematodes with different levels of expression of green fluorescent protein (GFP) were first mixed in a buffer solution. The worms were encapsulated in water-in-oil droplets to restrict random locomotion. The droplets were closely packed in a two-layer polydimethylsiloxane (PDMS) platform and were flowed through a narrow straight channel, in which a region of interest (ROI) was defined and continuously recorded by a frame acquisition device. Based on the number of pixels counted in the selected color range, our custom software analyzed GFP expression to differentiate between two strains with nearly 100% accuracy and a throughput of 0.5 seconds/worm.

  11. Real-time image processing of TOF range images using a reconfigurable processor system

    NASA Astrophysics Data System (ADS)

    Hussmann, S.; Knoll, F.; Edeler, T.

    2011-07-01

    During the last years, Time-of-Flight sensors achieved a significant impact onto research fields in machine vision. In comparison to stereo vision system and laser range scanners they combine the advantages of active sensors providing accurate distance measurements and camera-based systems recording a 2D matrix at a high frame rate. Moreover low cost 3D imaging has the potential to open a wide field of additional applications and solutions in markets like consumer electronics, multimedia, digital photography, robotics and medical technologies. This paper focuses on the currently implemented 4-phase-shift algorithm in this type of sensors. The most time critical operation of the phase-shift algorithm is the arctangent function. In this paper a novel hardware implementation of the arctangent function using a reconfigurable processor system is presented and benchmarked against the state-of-the-art CORDIC arctangent algorithm. Experimental results show that the proposed algorithm is well suited for real-time processing of the range images of TOF cameras.

  12. ISPATOM: A Generic Real-Time Data Processing Tool Without Programming

    NASA Technical Reports Server (NTRS)

    Dershowitz, Adam

    2007-01-01

    Information Sharing Protocol Advanced Tool of Math (ISPATOM) is an application program allowing for the streamlined generation of comps, which subscribe to streams of incoming telemetry data, perform any necessary computations on the data, then send the data to other programs for display and/or further processing in NASA mission control centers. Heretofore, the development of comps was difficult, expensive, and time-consuming: Each comp was custom written manually, in a low-level computing language, by a programmer attempting to follow requirements of flight controllers. ISPATOM enables a flight controller who is not a programmer to write a comp by simply typing in one or more equation( s) at a command line or retrieving the equation(s) from a text file. ISPATOM then subscribes to the necessary input data, performs all of necessary computations, and sends out the results. It sends out new results whenever the input data change. The use of equations in ISPATOM is no more difficult than is entering equations in a spreadsheet. The time involved in developing a comp is thus limited to the time taken to decide on the necessary equations. Thus, ISPATOM is a real-time dynamic calculator.

  13. Feature-level signal processing for near-real-time odor identification

    NASA Astrophysics Data System (ADS)

    Roppel, Thaddeus A.; Padgett, Mary Lou; Waldemark, Joakim T. A.; Wilson, Denise M.

    1998-09-01

    Rapid detection and classification of odor is of particular interest in applications such as manufacturing of consumer items, food processing, drug and explosives detection, and battlefield situation assessment. Various detection and classification techniques are under investigation so that end users can have access to useful information from odor sensor arrays in near-real-time. Feature-level data clustering and classification techniques are proposed that are (1) parallelizable to permit efficient hardware implementation, (2) adaptable to readily incorporate new data classes, (3) capable of gracefully handling outlier data points and failed sensor conditions, and (4) can provide confidence intervals and/or a traceable decision record along with each classification to permit validation and verification. Results from using specific techniques will be presented and compared. The techniques studied include principal components analysis, automated outlier determination, radial basis functions (RBF), multi-layer perceptrons (MLP), and pulse-coupled neural networks (PCNN). The results reported here are based on data from a testbed in which a gas sensor array is exposed to odor samples on a continuous basis. We have reported previously that more detailed and faster discrimination can be obtained by using sensor transient response in addition to steady state response. As the size of the data set grows we are able to more accurately model performance of a sensor array under realistic conditions.

  14. Real-time nonlinear finite element analysis for surgical simulation using graphics processing units.

    PubMed

    Taylor, Zeike A; Cheng, Mario; Ourselin, Sébastien

    2007-01-01

    Clinical employment of biomechanical modelling techniques in areas of medical image analysis and surgical simulation is often hindered by conflicting requirements for high fidelity in the modelling approach and high solution speeds. We report the development of techniques for high-speed nonlinear finite element (FE) analysis for surgical simulation. We employ a previously developed nonlinear total Lagrangian explicit FE formulation which offers significant computational advantages for soft tissue simulation. However, the key contribution of the work is the presentation of a fast graphics processing unit (GPU) solution scheme for the FE equations. To the best of our knowledge this represents the first GPU implementation of a nonlinear FE solver. We show that the present explicit FE scheme is well-suited to solution via highly parallel graphics hardware, and that even a midrange GPU allows significant solution speed gains (up to 16.4x) compared with equivalent CPU implementations. For the models tested the scheme allows real-time solution of models with up to 16000 tetrahedral elements. The use of GPUs for such purposes offers a cost-effective high-performance alternative to expensive multi-CPU machines, and may have important applications in medical image analysis and surgical simulation.

  15. Real-time measurements of crystallization processes in viscoelastic polymeric photonic crystals.

    PubMed

    Snoswell, David R E; Finlayson, Chris E; Zhao, Qibin; Baumberg, Jeremy J

    2015-11-01

    We present a study of the dynamic shear ordering of viscoelastic photonic crystals, based on core-shell polymeric composite particles. Using an adapted shear-cell arrangement, the crystalline ordering of the material under conditions of oscillatory shear is interrogated in real time, through both video imaging and from the optical transmission spectra of the cell. In order to gain a deeper understanding of the macroscopic influences of shear on the crystallization process in this solvent-free system, the development of bulk ordering is studied as a function of the key parameters including duty cycle and shear-strain magnitude. In particular, optimal ordering is observed from a prerandomized sample at shear strains of around 160%, for 1-Hz oscillations. This ordering reaches completion over time scales of order 10 s. These observations suggest significant local strains are needed to drive nanoparticles through energy barriers, and that local creep is needed to break temporal symmetry in such high-viscosity nanoassemblies. Crystal shear-melting effects are also characterized under conditions of constant shear rate. These quantitative experiments aim to stimulate the development of theoretical models which can deal with the strong local particle interactions in this system.

  16. Exploring socioeconomic differences in syntactic development through the lens of real-time processing.

    PubMed

    Huang, Yi Ting; Leech, Kathryn; Rowe, Meredith L

    2017-02-01

    Differences in caregiver input across socioeconomic status (SES) predict syntactic development, but the mechanisms are not well understood. Input effects may reflect the exposure needed to acquire syntactic representations during learning (e.g., does the child have the relevant structures for passive sentences?) or access this knowledge during communication (e.g., can she use the past participle to infer the meaning of passives?). Using an eye-tracking and act-out paradigm, the current study distinguishes these mechanisms by comparing the interpretation of actives and passives in 3- to 7-year-olds (n=129) from varying SES backgrounds. During the presentation of spoken sentences, fixations revealed robust disambiguation of constructions by children from higher-SES backgrounds, but less sensitivity by lower-SES counterparts. After sentence presentation, decreased sensitivity generated interpretive challenges and average SES-related differences for passives requiring syntactic revision ("The seal is quickly eaten by it"). Critically, no differences were found when revision was not needed ("It is quickly eaten by the seal"). These results suggest that all children shared an ability to acquire passives, but SES-related differences in real-time processing can impact the accuracy of utterance interpretation.

  17. New developments in real-time processing of full waveform acoustic televiewer data

    NASA Astrophysics Data System (ADS)

    Deltombe, Jean-Luc; Schepers, Reinhard

    2004-01-01

    The new full wave Acoustic Borehole Imager tool (ABI) is a multi-echo (amplitude and traveltime) system that gives optimum performance under a wide range of borehole conditions and is an improvement over existing single echo acoustic televiewer tools. The principle of the multi-echo system is the digital recording of each reflected acoustic wave train. Then, real-time processing of the acoustic data is made by a downhole Digital Signal Processor (DSP) to extract all valuable information, which is further compressed before transmission to the surface such that no special requirements are imposed on data transmission rates or on logging speed. Also, recording of the full acoustic waveform enables major improvements to the dynamic range of the system. Information about echoes from the tool's acoustic window provides the possibility to predict tool generated coherent noise and allows detection of echoes from the borehole wall, which are much smaller than coherent noise signals. When used in a PVC cased borehole, the system can be automatically adapted to record both the reflection at the casing and at the borehole wall. When used inside steel casing, the tool can detect echoes from the inner wall and the outer wall of the steel casing and the resulting data can used to calculate amount inner corrosion, outer corrosion, and remaining casing thickness. If the borehole casing was grouted with cement, information can be gathered about the presence and absence of cement and the quality of cement bonding.

  18. Real-time measurements of crystallization processes in viscoelastic polymeric photonic crystals

    NASA Astrophysics Data System (ADS)

    Snoswell, David R. E.; Finlayson, Chris E.; Zhao, Qibin; Baumberg, Jeremy J.

    2015-11-01

    We present a study of the dynamic shear ordering of viscoelastic photonic crystals, based on core-shell polymeric composite particles. Using an adapted shear-cell arrangement, the crystalline ordering of the material under conditions of oscillatory shear is interrogated in real time, through both video imaging and from the optical transmission spectra of the cell. In order to gain a deeper understanding of the macroscopic influences of shear on the crystallization process in this solvent-free system, the development of bulk ordering is studied as a function of the key parameters including duty cycle and shear-strain magnitude. In particular, optimal ordering is observed from a prerandomized sample at shear strains of around 160%, for 1-Hz oscillations. This ordering reaches completion over time scales of order 10 s. These observations suggest significant local strains are needed to drive nanoparticles through energy barriers, and that local creep is needed to break temporal symmetry in such high-viscosity nanoassemblies. Crystal shear-melting effects are also characterized under conditions of constant shear rate. These quantitative experiments aim to stimulate the development of theoretical models which can deal with the strong local particle interactions in this system.

  19. High resolution interface circuit for closed-loop accelerometer

    NASA Astrophysics Data System (ADS)

    Liang, Yin; Xiaowei, Liu; Weiping, Chen; Zhiping, Zhou

    2011-04-01

    This paper reports a low noise switched-capacitor CMOS interface circuit for the closed-loop operation of a capacitive accelerometer. The time division multiplexing of the same electrode is adopted to avoid the strong feedthrough between capacitance sensing and electrostatic force feedback. A PID controller is designed to ensure the stability and dynamic response of a high Q closed-loop accelerometer with a vacuum package. The architecture only requires single ended operational amplifiers, transmission gates and capacitors. Test results show that a full scale acceleration of ±3 g, non-linearity of 0.05% and signal bandwidth of 1000 Hz are achieved. The complete module operates from a ±5 V supply and has a measured sensitivity of 1.2 V/g with a noise of floor of in closed-loop. The chip is fabricated in the 2 μm two-metal and two-poly n-well CMOS process with an area of 15.2 mm2. These results prove that this circuit is suitable for high performance micro-accelerometer applications like seismic detection and oil exploration.

  20. Integrated otpical monitoring of MEMS for closed-loop control

    NASA Astrophysics Data System (ADS)

    Dawson, Jeremy M.; Wang, Limin; McCormick, W. B.; Rittenhouse, S. A.; Famouri, Parviz F.; Hornak, Lawrence A.

    2003-01-01

    Robust control and failure assessment of MEMS employed in physically demanding, mission critical applications will allow for higher degrees of quality assurance in MEMS operation. Device fault detection and closed-loop control require detailed knowledge of the operational states of MEMS over the lifetime of the device, obtained by a means decoupled from the system. Preliminary through-wafer optical monitoring research efforts have shown that through-wafer optical probing is suitable for characterizing and monitoring the behavior of MEMS, and can be implemented in an integrated optical monitoring package for continuous in-situ device monitoring. This presentation will discuss research undertaken to establish integrated optical device metrology for closed-loop control of a MUMPS fabricated lateral harmonic oscillator. Successful linear closed-loop control results using a through-wafer optical microprobe position feedback signal will be presented. A theoretical optical output field intensity study of grating structures, fabricated on the shuttle of the resonator, was performed to improve the position resolution of the optical microprobe position signal. Through-wafer microprobe signals providing a positional resolution of 2 μm using grating structures will be shown, along with initial binary Fresnel diffractive optical microelement design layout, process development, and testing results. Progress in the design, fabrication, and test of integrated optical elements for multiple microprobe signal delivery and recovery will be discussed, as well as simulation of device system model parameter changes for failure assessment.

  1. Real-time monitoring of calcification process by Sporosarcina pasteurii biofilm

    SciTech Connect

    Harris, Dustin; Ummadi, Jyothir Ganesh; Thurber, Andrew R.; Allau, Yvan; Verba, Circe; Colwell, Frederick; Torres, Marta E.; Koley, Dipankar

    2016-01-01

    Sporosarcina pasteurii is known to produce calcite or biocement in the presence of urea and Ca2+. Herein, we report the use of novel ultramicrosensors such as pH, Ca2+, and redox sensors, along with a scanning electrochemical microscope (SECM), to monitor a real-time, bacteria-mediated urea hydrolysis process and subsequent changes in morphology due to CaCO3 precipitation. We report that the surface pH of a live biofilm changed rapidly from 7.4 to 9.2 within 2 min, whereas similar fast depletion (10 min) of Ca2+ was observed from 85 mM to 10 mM in the presence of a high urea (10 g L-1) brine solution at 23 °C. Both the pH and the Ca2+ concentration profiles were extended up to 600 μm from the biofilm surface, whereas the bulk chemical composition of the brine solution remained constant over the entire 4 h of SECM experiments. In addition, we observed a change in biofilm surface morphology and an increase in overall biofilm height of 50 μm after 4 h of precipitation. Electron microscopy confirmed the changes in surface morphology and formation of CaCO3 crystals. Development of the Ca2+ profile took 10 min, whereas that of the pH profile took 2 min. This finding indicates that the initial urea hydrolysis process is fast and limited by urease or number of bacteria, whereas later CaCO3 formation and growth of crystals is a slow chemical process. The ultramicrosensors and approaches employed here are capable of accurately characterizing bioremediation on temporal and spatial scales pertinent to the microbial communities and the processes they mediate.

  2. Real-time monitoring of calcification process by Sporosarcina pasteurii biofilm.

    PubMed

    Harris, Dustin; Ummadi, Jyothir Ganesh; Thurber, Andrew R; Allau, Yvan; Verba, Circe; Colwell, Frederick; Torres, Marta E; Koley, Dipankar

    2016-05-10

    Sporosarcina pasteurii is known to produce calcite or biocement in the presence of urea and Ca(2+). Herein, we report the use of novel ultramicrosensors such as pH, Ca(2+), and redox sensors, along with a scanning electrochemical microscope (SECM), to monitor a real-time, bacteria-mediated urea hydrolysis process and subsequent changes in morphology due to CaCO3 precipitation. We report that the surface pH of a live biofilm changed rapidly from 7.4 to 9.2 within 2 min, whereas similar fast depletion (10 min) of Ca(2+) was observed from 85 mM to 10 mM in the presence of a high urea (10 g L(-1)) brine solution at 23 °C. Both the pH and the Ca(2+) concentration profiles were extended up to 600 μm from the biofilm surface, whereas the bulk chemical composition of the brine solution remained constant over the entire 4 h of SECM experiments. In addition, we observed a change in biofilm surface morphology and an increase in overall biofilm height of 50 μm after 4 h of precipitation. Electron microscopy confirmed the changes in surface morphology and formation of CaCO3 crystals. Development of the Ca(2+) profile took 10 min, whereas that of the pH profile took 2 min. This finding indicates that the initial urea hydrolysis process is fast and limited by urease or number of bacteria, whereas later CaCO3 formation and growth of crystals is a slow chemical process. The ultramicrosensors and approaches employed here are capable of accurately characterizing bioremediation on temporal and spatial scales pertinent to the microbial communities and the processes they mediate.

  3. Real-time detection of undersea mines: a complete screening and acoustic fusion processing system

    NASA Astrophysics Data System (ADS)

    Sacramone, Anthony; Desai, Mukund N.

    1999-08-01

    A complete mine detection/classification (D/C) system has been specified and implemented, which runs in real-time, and has been exercised on the latest available dual-frequency side-scan sonar acoustic image sets. The compete DC system is comprised of a collection of algorithms that has been developed and evolved at Draper Laboratory over the past decade. The detection process consists of image normalization, enhancement, segmentation, and feature extraction algorithms. The enhancement algorithm is a variant of a Markov Random Field based anomaly screener developed in FY-94. The feature that were extracted were those derived in FY-93. A distance constrained matching algorithm, which was developed in FY-95, is used to generate a list of high and low frequency fused tokens. The classification process involves the evaluation of a hierarchy of three multi-layer perceptron neural networks: HF, LF, and HF/LF fused. Research performed in FY-95 also concentrated on the development of several variants of information fusion with hierarchical neural networks. The 'discriminant-combining' variant of fusion was selected as part of this DC system. In addition, a classification post- processing and decision node statistic modification step, which was developed in FY-96, was included. This paper will describe the algorithm that were implemented. However, the emphasis will be on the performance results of processing the latest available side-scan imagery, comparison of single sensor vs dual-frequency sensor results, and the issues that were encountered while exercising the DC system on the new data set.

  4. Real time intelligent process control system for thin film solar cell manufacturing

    SciTech Connect

    George Atanasoff

    2010-10-29

    This project addresses the problem of lower solar conversion efficiency and waste in the typical solar cell manufacturing process. The work from the proposed development will lead toward developing a system which should be able to increase solar panel conversion efficiency by an additional 12-15% resulting in lower cost panels, increased solar technology adoption, reduced carbon emissions and reduced dependency on foreign oil. All solar cell manufacturing processes today suffer from manufacturing inefficiencies that currently lead to lower product quality and lower conversion efficiency, increased product cost and greater material and energy consumption. This results in slower solar energy adoption and extends the time solar cells will reach grid parity with traditional energy sources. The thin film solar panel manufacturers struggle on a daily basis with the problem of thin film thickness non-uniformity and other parameters variances over the deposited substrates, which significantly degrade their manufacturing yield and quality. Optical monitoring of the thin films during the process of the film deposition is widely perceived as a necessary step towards resolving the non-uniformity and non-homogeneity problem. In order to enable the development of an optical control system for solar cell manufacturing, a new type of low cost optical sensor is needed, able to acquire local information about the panel under deposition and measure its local characteristics, including the light scattering in very close proximity to the surface of the film. This information cannot be obtained by monitoring from outside the deposition chamber (as traditional monitoring systems do) due to the significant signal attenuation and loss of its scattering component before the reflected beam reaches the detector. In addition, it would be too costly to install traditional external in-situ monitoring systems to perform any real-time monitoring over large solar panels, since it would require

  5. Bidirectional neural interface: Closed-loop feedback control for hybrid neural systems.

    PubMed

    Chou, Zane; Lim, Jeffrey; Brown, Sophie; Keller, Melissa; Bugbee, Joseph; Broccard, Frédéric D; Khraiche, Massoud L; Silva, Gabriel A; Cauwenberghs, Gert

    2015-01-01

    Closed-loop neural prostheses enable bidirectional communication between the biological and artificial components of a hybrid system. However, a major challenge in this field is the limited understanding of how these components, the two separate neural networks, interact with each other. In this paper, we propose an in vitro model of a closed-loop system that allows for easy experimental testing and modification of both biological and artificial network parameters. The interface closes the system loop in real time by stimulating each network based on recorded activity of the other network, within preset parameters. As a proof of concept we demonstrate that the bidirectional interface is able to establish and control network properties, such as synchrony, in a hybrid system of two neural networks more significantly more effectively than the same system without the interface or with unidirectional alternatives. This success holds promise for the application of closed-loop systems in neural prostheses, brain-machine interfaces, and drug testing.

  6. Closed-Loop Resuscitation of Hemorrhagic Shock

    DTIC Science & Technology

    2011-02-21

    thank ONR for the last 9 years of basic and applied research on titrated fluid therapy of hypovolemic shock . This grant was instrumental in not only the...Phone: 409-772-3969 Fax: 409-772-8895 Project Title: Closed-Loop Resuscitation of Hemorrhagic Shock ONR Award No: N000140610300 Organization...Resuscitation Of Hemorrhagic Shock 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK

  7. Closed loop orbit trim using GPS

    NASA Technical Reports Server (NTRS)

    Parkinson, B. W.; Axelrad, P.

    1989-01-01

    This paper describes an onboard closed-loop navigation and control system capable of executing extremely precise orbit maneuvers. It uses information from the Global Positioning System (GPS) and an onboard controller to perform orbit adjustments. As a result, the system circumvents the need for extensive ground support. The particular application considered is an orbit injection system for NASA's Gravity Probe B (GP-B) spacecraft. Eccentricity adjustments of 0.0004 to 0.005, and inclination and node changes of 0.001 to 0.01 deg are demonstrated. The same technique can be adapted to other satellite missions.

  8. Optimal swab processing recovery method for detection of bioterrorism-related Francisella tularensis by real-time PCR.

    PubMed

    Walker, Roblena E; Petersen, Jeannine M; Stephens, Kenyatta W; Dauphin, Leslie A

    2010-10-01

    Francisella tularensis, the etiological agent of tularemia, is regarded as a potential bioterrorism agent. The advent of bioterrorism has heightened awareness of the need for validated methods for processing environmental samples. In this study we determined the optimal method for processing environmental swabs for the recovery and subsequent detection of F. tularensis by the use of real-time PCR assays. Four swab processing recovery methods were compared: heat, sonication, vortexing, and the Swab Extraction Tube System (SETS). These methods were evaluated using cotton, foam, polyester and rayon swabs spiked with six pathogenic strains of F. tularensis. Real-time PCR analysis using a multi-target 5'nuclease assay for F. tularensis showed that the use of the SETS method resulted in the best limit of detection when evaluated using multiple strains of F. tularensis. We demonstrated also that the efficiency of F. tularensis recovery from swab specimens was not equivalent for all swab processing methodologies and, thus, that this variable can affect real-time PCR assay sensitivity. The effectiveness of the SETS method was independent of the automated DNA extraction method and real-time PCR platforms used. In conclusion, diagnostic laboratories can now potentially incorporate the SETS method into specimen processing protocols for the rapid and efficient detection of F. tularensis by real-time PCR during laboratory bioterrorism-related investigations.

  9. Process Mining Methodology for Health Process Tracking Using Real-Time Indoor Location Systems

    PubMed Central

    Fernandez-Llatas, Carlos; Lizondo, Aroa; Monton, Eduardo; Benedi, Jose-Miguel; Traver, Vicente

    2015-01-01

    The definition of efficient and accurate health processes in hospitals is crucial for ensuring an adequate quality of service. Knowing and improving the behavior of the surgical processes in a hospital can improve the number of patients that can be operated on using the same resources. However, the measure of this process is usually made in an obtrusive way, forcing nurses to get information and time data, affecting the proper process and generating inaccurate data due to human errors during the stressful journey of health staff in the operating theater. The use of indoor location systems can take time information about the process in an unobtrusive way, freeing nurses, allowing them to engage in purely welfare work. However, it is necessary to present these data in a understandable way for health professionals, who cannot deal with large amounts of historical localization log data. The use of process mining techniques can deal with this problem, offering an easily understandable view of the process. In this paper, we present a tool and a process mining-based methodology that, using indoor location systems, enables health staff not only to represent the process, but to know precise information about the deployment of the process in an unobtrusive and transparent way. We have successfully tested this tool in a real surgical area with 3613 patients during February, March and April of 2015. PMID:26633395

  10. Process Mining Methodology for Health Process Tracking Using Real-Time Indoor Location Systems.

    PubMed

    Fernandez-Llatas, Carlos; Lizondo, Aroa; Monton, Eduardo; Benedi, Jose-Miguel; Traver, Vicente

    2015-11-30

    The definition of efficient and accurate health processes in hospitals is crucial for ensuring an adequate quality of service. Knowing and improving the behavior of the surgical processes in a hospital can improve the number of patients that can be operated on using the same resources. However, the measure of this process is usually made in an obtrusive way, forcing nurses to get information and time data, affecting the proper process and generating inaccurate data due to human errors during the stressful journey of health staff in the operating theater. The use of indoor location systems can take time information about the process in an unobtrusive way, freeing nurses, allowing them to engage in purely welfare work. However, it is necessary to present these data in a understandable way for health professionals, who cannot deal with large amounts of historical localization log data. The use of process mining techniques can deal with this problem, offering an easily understandable view of the process. In this paper, we present a tool and a process mining-based methodology that, using indoor location systems, enables health staff not only to represent the process, but to know precise information about the deployment of the process in an unobtrusive and transparent way. We have successfully tested this tool in a real surgical area with 3613 patients during February, March and April of 2015.

  11. CLOSED-LOOP STRIPPING ANALYSIS (CLSA) OF ...

    EPA Pesticide Factsheets

    Synthetic musk compounds have been found in surface water, fish tissues, and human breast milk. Current techniques for separating these compounds from fish tissues require tedious sample clean-upprocedures A simple method for the deterrnination of these compounds in fish tissues has been developed. Closed-loop stripping of saponified fish tissues in a I -L Wheaton purge-and-trap vessel is used to strip compounds with high vapor pressures such as synthetic musks from the matrix onto a solid sorbent (Abselut Nexus). This technique is useful for screening biological tissues that contain lipids for musk compounds. Analytes are desorbed from the sorbent trap sequentially with polar and nonpolar solvents, concentrated, and directly analyzed by high resolution gas chromatography coupled to a mass spectrometer operating in the selected ion monitoring mode. In this paper, we analyzed two homogenized samples of whole fish tissues with spiked synthetic musk compounds using closed-loop stripping analysis (CLSA) and pressurized liquid extraction (PLE). The analytes were not recovered quantitatively but the extraction yield was sufficiently reproducible for at least semi-quantitative purposes (screening). The method was less expensive to implement and required significantly less sample preparation than the PLE technique. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water,

  12. Near Real-Time Photometric Data Processing for the Solar Mass Ejection Imager (SMEI)

    NASA Astrophysics Data System (ADS)

    Hick, P. P.; Buffington, A.; Jackson, B. V.

    2004-12-01

    The Solar Mass Ejection Imager (SMEI) records a photometric white-light response of the interplanetary medium from Earth over most of the sky in near real time. In the first two years of operation the instrument has recorded the inner heliospheric response to several hundred CMEs, including the May 28, 2003 and the October 28, 2003 halo CMEs. In this preliminary work we present the techniques required to process the SMEI data from the time the raw CCD images become available to their final assembly in photometrically accurate maps of the sky brightness relative to a long-term time base. Processing of the SMEI data includes integration of new data into the SMEI data base; a conditioning program that removes from the raw CCD images an electronic offset ("pedestal") and a temperature-dependent dark current pattern; an "indexing" program that places these CCD images onto a high-resolution sidereal grid using known spacecraft pointing information. At this "indexing" stage further conditioning removes the bulk of the the effects of high-energy-particle hits ("cosmic rays"), space debris inside the field of view, and pixels with a sudden state change ("flipper pixels"). Once the high-resolution grid is produced, it is reformatted to a lower-resolution set of sidereal maps of sky brightness. From these sidereal maps we remove bright stars, background stars, and a zodiacal cloud model (their brightnesses are retained as additional data products). The final maps can be represented in any convenient sky coordinate system. Common formats are Sun-centered Hammer-Aitoff or "fisheye" maps. Time series at selected locations on these maps are extracted and processed further to remove aurorae, variable stars and other unwanted signals. These time series (with a long-term base removed) are used in 3D tomographic reconstructions. The data processing is distributed over multiple PCs running Linux, and, runs as much as possible automatically using recurring batch jobs ('cronjobs'). The

  13. Real-time computation of parameter fitting and image reconstruction using graphical processing units

    NASA Astrophysics Data System (ADS)

    Locans, Uldis; Adelmann, Andreas; Suter, Andreas; Fischer, Jannis; Lustermann, Werner; Dissertori, Günther; Wang, Qiulin

    2017-06-01

    In recent years graphical processing units (GPUs) have become a powerful tool in scientific computing. Their potential to speed up highly parallel applications brings the power of high performance computing to a wider range of users. However, programming these devices and integrating their use in existing applications is still a challenging task. In this paper we examined the potential of GPUs for two different applications. The first application, created at Paul Scherrer Institut (PSI), is used for parameter fitting during data analysis of μSR (muon spin rotation, relaxation and resonance) experiments. The second application, developed at ETH, is used for PET (Positron Emission Tomography) image reconstruction and analysis. Applications currently in use were examined to identify parts of the algorithms in need of optimization. Efficient GPU kernels were created in order to allow applications to use a GPU, to speed up the previously identified parts. Benchmarking tests were performed in order to measure the achieved speedup. During this work, we focused on single GPU systems to show that real time data analysis of these problems can be achieved without the need for large computing clusters. The results show that the currently used application for parameter fitting, which uses OpenMP to parallelize calculations over multiple CPU cores, can be accelerated around 40 times through the use of a GPU. The speedup may vary depending on the size and complexity of the problem. For PET image analysis, the obtained speedups of the GPU version were more than × 40 larger compared to a single core CPU implementation. The achieved results show that it is possible to improve the execution time by orders of magnitude.

  14. Continuous Glucose Monitoring Considerations for the Development of a Closed-Loop Artificial Pancreas System

    PubMed Central

    Keenan, D Barry; Grosman, Benyamin; Clark, Harry W; Roy, Anirban; Weinzimer, Stuart A; Shah, Rajiv V; Mastrototaro, John J

    2011-01-01

    Background Commercialization of a closed-loop artificial pancreas system that employs continuous subcutaneous insulin infusion and interstitial fluid glucose sensing has been encumbered by state-of-the-art technology. Continuous glucose monitoring (CGM) devices with improved accuracy could significantly advance development efforts. However, the current accuracy of CGM devices might be adequate for closed-loop control. Methods The influence that known CGM limitations have on closed-loop control was investigated by integrating sources of sensor inaccuracy with the University of Virginia Padova Diabetes simulator. Non-glucose interference, physiological time lag and sensor error measurements, selected from 83 Enlite™ glucose sensor recordings with the Guardian® REAL-Time system, were used to modulate simulated plasma glucose signals. The effect of sensor accuracy on closed-loop controller performance was evaluated in silico, and contrasted with closed-loop clinical studies during the nocturnal control period. Results Based on n = 2472 reference points, a mean sensor error of 14% with physiological time lags of 3.28 ± 4.62 min (max 13.2 min) was calculated for simulation. Sensor bias reduced time in target for both simulation and clinical experiments. In simulation, additive error increased time <70 mg/dl and >180 mg/dl by 0.2% and 5.6%, respectively. In-clinic, the greatest low blood glucose index values (max = 5.9) corresponded to sensor performance. Conclusion Sensors have sufficient accuracy for closed-loop control, however, algorithms are necessary to effectively calibrate and detect erroneous calibrations and failing sensors. Clinical closed-loop data suggest that control with a higher target of 140 mg/dl during the nocturnal period could significantly reduce the risk for hypoglycemia. PMID:22226249

  15. Processing of gene expression data generated by quantitative real-time RT-PCR.

    PubMed

    Muller, Patrick Y; Janovjak, Harald; Miserez, André R; Dobbie, Zuzana

    2002-06-01

    Quantitative real-time PCR represents a highly sensitive and powerful technique for the quantitation of nucleic acids. It has a tremendous potential for the high-throughput analysis of gene expression in research and routine diagnostics. However, the major hurdle is not the practical performance of the experiments themselves but rather the efficient evaluation and the mathematical and statistical analysis of the enormous amount of data gained by this technology, as these functions are not included in the software provided by the manufacturers of the detection systems. In this work, we focus on the mathematical evaluation and analysis of the data generated by quantitative real-time PCR, the calculation of the final results, the propagation of experimental variation of the measured values to the final results, and the statistical analysis. We developed a Microsoft Excel-based software application coded in Visual Basic for Applications, called Q-Gene, which addresses these points. Q-Gene manages and expedites the planning, performance, and evaluation of quantitative real-time PCR experiments, as well as the mathematical and statistical analysis, storage, and graphical presentation of the data. The Q-Gene software application is a tool to cope with complex quantitative real-time PCR experiments at a high-throughput scale and considerably expedites and rationalizes the experimental setup, data analysis, and data management while ensuring highest reproducibility.

  16. Development of a fluid bed granulation process control strategy based on real-time process and product measurements.

    PubMed

    Burggraeve, Anneleen; Silva, Ana F T; Van den Kerkhof, Tom; Hellings, Mario; Vervaet, Chris; Remon, Jean Paul; Vander Heyden, Yvan; De Beer, Thomas

    2012-10-15

    This article describes the results of three case studies conducted consecutively, in order to develop a process control strategy for a top-spray fluid bed granulation process. The use of several real-time particle size (i.e., spatial filter velocimetry and focused beam reflectance measurement) and moisture (i.e., near infrared (NIR) and Lighthouse near infrared spectroscopy) analyzers was examined. A feed-forward process control method was developed, where in-line collected granulation information during the process spraying phase was used to determine the optimum drying temperature of the consecutive drying phase. Via real-time monitoring of process (i.e., spraying temperature and spray rate) and product (i.e., granule size distribution and moisture) parameters during the spraying period, the batch bulk density was predicted at the end of the spraying cycle, using a PLS model. When this predicted bulk density was not meeting the desired value, the developed control method allowed the calculation of an adjusted drying temperature leading to the desired batch bulk density at the end of the granulation process. Besides the development of the feed-forward control strategy, a quantitative PLS model for in-line moisture content prediction of the granulated end product was built using the NIR data.

  17. WINCS Harmoni: Closed-loop dynamic neurochemical control of therapeutic interventions

    NASA Astrophysics Data System (ADS)

    Lee, Kendall H.; Lujan, J. Luis; Trevathan, James K.; Ross, Erika K.; Bartoletta, John J.; Park, Hyung Ook; Paek, Seungleal Brian; Nicolai, Evan N.; Lee, Jannifer H.; Min, Hoon-Ki; Kimble, Christopher J.; Blaha, Charles D.; Bennet, Kevin E.

    2017-04-01

    There has been significant progress in understanding the role of neurotransmitters in normal and pathologic brain function. However, preclinical trials aimed at improving therapeutic interventions do not take advantage of real-time in vivo neurochemical changes in dynamic brain processes such as disease progression and response to pharmacologic, cognitive, behavioral, and neuromodulation therapies. This is due in part to a lack of flexible research tools that allow in vivo measurement of the dynamic changes in brain chemistry. Here, we present a research platform, WINCS Harmoni, which can measure in vivo neurochemical activity simultaneously across multiple anatomical targets to study normal and pathologic brain function. In addition, WINCS Harmoni can provide real-time neurochemical feedback for closed-loop control of neurochemical levels via its synchronized stimulation and neurochemical sensing capabilities. We demonstrate these and other key features of this platform in non-human primate, swine, and rodent models of deep brain stimulation (DBS). Ultimately, systems like the one described here will improve our understanding of the dynamics of brain physiology in the context of neurologic disease and therapeutic interventions, which may lead to the development of precision medicine and personalized therapies for optimal therapeutic efficacy.

  18. WINCS Harmoni: Closed-loop dynamic neurochemical control of therapeutic interventions

    PubMed Central

    Lee, Kendall H.; Lujan, J. Luis; Trevathan, James K.; Ross, Erika K.; Bartoletta, John J.; Park, Hyung Ook; Paek, Seungleal Brian; Nicolai, Evan N.; Lee, Jannifer H.; Min, Hoon-Ki; Kimble, Christopher J.; Blaha, Charles D.; Bennet, Kevin E.

    2017-01-01

    There has been significant progress in understanding the role of neurotransmitters in normal and pathologic brain function. However, preclinical trials aimed at improving therapeutic interventions do not take advantage of real-time in vivo neurochemical changes in dynamic brain processes such as disease progression and response to pharmacologic, cognitive, behavioral, and neuromodulation therapies. This is due in part to a lack of flexible research tools that allow in vivo measurement of the dynamic changes in brain chemistry. Here, we present a research platform, WINCS Harmoni, which can measure in vivo neurochemical activity simultaneously across multiple anatomical targets to study normal and pathologic brain function. In addition, WINCS Harmoni can provide real-time neurochemical feedback for closed-loop control of neurochemical levels via its synchronized stimulation and neurochemical sensing capabilities. We demonstrate these and other key features of this platform in non-human primate, swine, and rodent models of deep brain stimulation (DBS). Ultimately, systems like the one described here will improve our understanding of the dynamics of brain physiology in the context of neurologic disease and therapeutic interventions, which may lead to the development of precision medicine and personalized therapies for optimal therapeutic efficacy. PMID:28452348

  19. Applications of neural networks to real-time data processing at the Environmental and Molecular Sciences Laboratory (EMSL)

    SciTech Connect

    Keller, P.E.; Kouzes, R.T.; Kangas, L.J.

    1993-06-01

    Detailed design of the Environmental and Molecular Sciences Laboratory (EMSL) at the Pacific Northwest Laboratory (PNL) is nearing completion and construction is scheduled to begin later this year. This facility will assist in the environmental restoration and waste management mission at the Hanford Site. This paper identifies several real-time data processing applications within the EMSL where neural networks can potentially be beneficial. These applications include real-time sensor data acquisition and analysis, spectral analysis, process control, theoretical modeling, and data compression.

  20. A State-of-the-Art Review of the Real-Time Computer-Aided Study of the Writing Process

    ERIC Educational Resources Information Center

    Abdel Latif, Muhammad M.

    2008-01-01

    Writing researchers have developed various methods for investigating the writing process since the 1970s. The early 1980s saw the occurrence of the real-time computer-aided study of the writing process that relies on the protocols generated by recording the computer screen activities as writers compose using the word processor. This article…

  1. A comparison of real-time performance of signal processing algorithms for minimum latency detection of hypovolemic States.

    PubMed

    Jovanov, Emil; Cox, Paul; Saul, J Philip; Salinas, Jose; Ryan, Kathy L; Convertino, Victor A

    2006-01-01

    Algorithms for real-time ambulatory monitoring of physiological signals often run on platforms which have very limited processing power and memory. Therefore, in addition to functionality, it is necessary to carefully consider real-time performance requirements. This is particularly important for physiological monitoring of life threatening conditions such as hemorrhage. In this paper we present a comparison of several algorithms as candidates for implementation on a prehospital ambulatory monitor of hypovolemic states. The algorithms were tested on data from lower body negative pressure (LBNP) experiments that were used to simulate hypovolemic states. We also present a promising real-time wavelet algorithm for heart rate variability (HRV) processing in prehospital ambulatory monitoring applications.

  2. Real-time detection of focal position of workpiece surface during laser processing using diffractive beam samplers

    NASA Astrophysics Data System (ADS)

    Cao, Binh Xuan; Hoang, PhuongLe; Ahn, Sanghoon; Kim, Jeng-o.; Sohn, Hyonkee; Noh, Jiwhan

    2016-11-01

    The real-time fabrication of microgrooves on a curved surface using a laser beam, without preprogramming their shapes into the machining instructions, is a major challenge in laser processing owing to limitations associated with the real-time detection of the focal position. A new approach using a sampled fraction of the beam from a diffractive beam sampler (DBS) is therefore presented in order to overcome this limitation. By considering the sampled fraction of the beam an analysis of the results allows for precise positioning of the specimen for focal-point identification. This allows for the determination of the focus for a broad variety of laser types and laser powers, thereby providing stringent focusing conditions with high numerical apertures. This approach is easy to implement, inexpensive, independent of the roughness or granularity of the workpieces, and more importantly does not require auxiliary lasers and displacement sensors for real-time measurement during the fabrication process.

  3. Real-time detection of optical transients with RAPTOR

    SciTech Connect

    Borozdin, K. N.; Brumby, Steven P.; Galassi, M. C.; McGowan, K. E.; Starr, D. L.; Vestrand, W. T.; White, R. R.; Wozniak, P. R.; Wren, J.

    2002-01-01

    Fast variability of optical objects is an interesting though poorly explored subject in modern astronomy. Real-time data processing and identification of transient, celestial events in the images is very important, for such study as it allows rapid follow-up with more sensitive instruments, We discuss an approach which we have chosen for the RAPTOR project which is a pioneering close-loop system combining real-time transient detection with rapid follow-up. Our data processing pipeline is able to identify and localize an optical transient within seconds after the observation. We describe the challenges we met, solutions we found and some results obtained in our search for fast optical transients. The software pipeline we have developed for RAPTOR can easily be applied to the data from other experiments.

  4. Monitoring Digital Closed-Loop Feedback Systems

    NASA Technical Reports Server (NTRS)

    Katz, Richard; Kleyner, Igor

    2011-01-01

    A technique of monitoring digital closed-loop feedback systems has been conceived. The basic idea is to obtain information on the performances of closed-loop feedback circuits in such systems to aid in the determination of the functionality and integrity of the circuits and of performance margins. The need for this technique arises as follows: Some modern digital systems include feedback circuits that enable other circuits to perform with precision and are tolerant of changes in environment and the device s parameters. For example, in a precision timing circuit, it is desirable to make the circuit insensitive to variability as a result of the manufacture of circuit components and to the effects of temperature, voltage, radiation, and aging. However, such a design can also result in masking the indications of damaged and/or deteriorating components. The present technique incorporates test circuitry and associated engineering-telemetry circuitry into an embedded system to monitor the closed-loop feedback circuits, using spare gates that are often available in field programmable gate arrays (FPGAs). This technique enables a test engineer to determine the amount of performance margin in the system, detect out of family circuit performance, and determine one or more trend(s) in the performance of the system. In one system to which the technique has been applied, an ultra-stable oscillator is used as a reference for internal adjustment of 12 time-to-digital converters (TDCs). The feedback circuit produces a pulse-width-modulated signal that is fed as a control input into an amplifier, which controls the circuit s operating voltage. If the circuit s gates are determined to be operating too slowly or rapidly when their timing is compared with that of the reference signal, then the pulse width increases or decreases, respectively, thereby commanding the amplifier to increase or reduce, respectively, its output level, and "adjust" the speed of the circuits. The nominal

  5. Graphics processing unit-accelerated real-time compressive sensing spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Xu, Daguang; Huang, Yong; Kang, Jin U.

    2015-03-01

    In this paper, we systematically demonstrate two real-time CS SD OCT systems based on a conventional desktop having three GPUs. The first one takes fast Fourier transform (FFT) as the sensing technique and under-sampled linear wavenumber spectral sampling as input data, while the second one uses non-uniform fast Fourier transform (NUFFT) and under-sampled nonlinear wavenumber spectral sampling, respectively. The maximum reconstruction speed of 72k and 33.5k A-line/s were achieved for these two systems, respectively, with A-scan size 2048. It is >100 times faster than the C++ implementation and >400 times faster than the MATLAB implementation. Finally, we present real-time dispersion compensated image reconstruction for both systems.

  6. Real-time Process Monitoring and Temperature Mapping of the 3D Polymer Printing Process

    SciTech Connect

    Dinwiddie, Ralph Barton; Love, Lonnie J; Rowe, John C

    2013-01-01

    An extended range IR camera was used to make temperature measurements of samples as they are being manufactured. The objective is to quantify the temperature variation inside the system as parts are being fabricated, as well as quantify the temperature of a part during fabrication. The IR camera was used to map the temperature within the build volume of the oven and surface temperature measurement of a part as it was being manufactured. The development of the temperature map of the oven provides insight into the global temperature variation within the oven that may lead to understanding variations in the properties of parts as a function of location. The observation of the temperature variation of a part that fails during construction provides insight into how the deposition process itself impacts temperature distribution within a single part leading to failure.

  7. Real-time monitoring and control of the plasma hearth process

    SciTech Connect

    Power, M.A.; Carney, K.P.; Peters, G.G.

    1996-05-01

    A distributed monitoring and control system is proposed for a plasma hearth, which will be used to decompose hazardous organic materials, encapsulate actinide waste in an obsidian-like slag, and reduce storage volume of actinide waste. The plasma hearth will be installed at ANL-West with the assistance of SAIC. Real-time monitoring of the off-gas system is accomplished using a Sun Workstation and embedded PCs. LabWindows/CVI software serves as the graphical user interface.

  8. Automatic procedure for quasi-real time seismic data processing at Campi Flegrei (Italy)

    NASA Astrophysics Data System (ADS)

    Capuano, Paolo; Ciaramella, Angelo; De Lauro, Enza; De Martino, Salvatore; Falanga, Mariarosaria; Petrosino, Simona

    2014-05-01

    The accuracy of automatic procedures for detecting seismic events and locating their sources is influenced by several factors such as errors in picking seismic phases often buried in the high-level ambient noise, network geometry and modelling errors. fundamental objective is the improvement of these procedures by developing accurate algorithms for quasi-real time seismic data processing, easily managed in observatory practice. Recently a robust automatic procedure has been implemented for detecting, onset picking and identifying signal phases in continuous seismic signal with an application at the seismicity recorded at Campi Flegrei Caldera (Italy) during the 2006 ground uplift (Ciaramella et al. 2011). An Independent Component Analysis based approach for the Blind Source Separation of convolutive mixtures (CICA) has been adopted to obtain a clear separation of low-energy Long Period events (LPs) from the high-level ambient noise allowing to compile a complete seismic catalogue and better quantify the seismic energy release. In this work, we apply CICA at the seismic signal continuously recorded during the entire 2006 at Campi Flegrei. First, we have performed tests on synthetic data in order to improve the reliability and the accuracy of the procedure. The performance test using very noisy synthetic data shows that the method works even in case of very poor quality data characterized by very low signal to noise ratio (SNR). Second, we have improved CICA automatic procedure recovering the information on the amplitudes of the extracted independent components. This is crucial for further analysis, starting from a prompt estimate of magnitude/energy of the highlighted events. Data used for the present analysis were collected by four broadband three-component seismic stations (ASB2, AMS2, TAGG, BGNG) belonging to the Campi Flegrei seismic monitoring network, managed by the 'Istituto Nazionale di Geofisica e Vulcanologia-Osservatorio Vesuviano (INGV-OV)' (see for

  9. Near Real-Time Closed-Loop Optimal Control Feedback for Spacecraft Attitude Maneuvers

    DTIC Science & Technology

    2009-03-01

    including [19] [25] [48] [26] [30]. However, SimSAT I had limitations as noted by Rohe, Roach and Welty . ...SimSAT did have limitations. Due to its...that was designed and built by Roach, Rohe, and Welty between 2007 and 2008 [40]. It consists of three major hardware systems: • a Ground Station...system. As a result, the SimSAT II Ground Station utilized by Roach, Rohe, and Welty was upgraded from a standard dual processor desktop by 2008

  10. Command-line cellular electrophysiology for conventional and real-time closed-loop experiments.

    PubMed

    Linaro, Daniele; Couto, João; Giugliano, Michele

    2014-06-15

    Current software tools for electrophysiological experiments are limited in flexibility and rarely offer adequate support for advanced techniques such as dynamic clamp and hybrid experiments, which are therefore limited to laboratories with a significant expertise in neuroinformatics. We have developed lcg, a software suite based on a command-line interface (CLI) that allows performing both standard and advanced electrophysiological experiments. Stimulation protocols for classical voltage and current clamp experiments are defined by a concise and flexible meta description that allows representing complex waveforms as a piece-wise parametric decomposition of elementary sub-waveforms, abstracting the stimulation hardware. To perform complex experiments lcg provides a set of elementary building blocks that can be interconnected to yield a large variety of experimental paradigms. We present various cellular electrophysiological experiments in which lcg has been employed, ranging from the automated application of current clamp protocols for characterizing basic electrophysiological properties of neurons, to dynamic clamp, response clamp, and hybrid experiments. We finally show how the scripting capabilities behind a CLI are suited for integrating experimental trials into complex workflows, where actual experiment, online data analysis and computational modeling seamlessly integrate. We compare lcg with two open source toolboxes, RTXI and RELACS. We believe that lcg will greatly contribute to the standardization and reproducibility of both simple and complex experiments. Additionally, on the long run the increased efficiency due to a CLI will prove a great benefit for the experimental community. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. A neuron-inspired computational architecture for spatiotemporal visual processing: real-time visual sensory integration for humanoid robots.

    PubMed

    Holzbach, Andreas; Cheng, Gordon

    2014-06-01

    In this article, we present a neurologically motivated computational architecture for visual information processing. The computational architecture's focus lies in multiple strategies: hierarchical processing, parallel and concurrent processing, and modularity. The architecture is modular and expandable in both hardware and software, so that it can also cope with multisensory integrations - making it an ideal tool for validating and applying computational neuroscience models in real time under real-world conditions. We apply our architecture in real time to validate a long-standing biologically inspired visual object recognition model, HMAX. In this context, the overall aim is to supply a humanoid robot with the ability to perceive and understand its environment with a focus on the active aspect of real-time spatiotemporal visual processing. We show that our approach is capable of simulating information processing in the visual cortex in real time and that our entropy-adaptive modification of HMAX has a higher efficiency and classification performance than the standard model (up to ∼+6%).

  12. Video enhancement workbench: an operational real-time video image processing system

    NASA Astrophysics Data System (ADS)

    Yool, Stephen R.; Van Vactor, David L.; Smedley, Kirk G.

    1993-01-01

    Video image sequences can be exploited in real-time, giving analysts rapid access to information for military or criminal investigations. Video-rate dynamic range adjustment subdues fluctuations in image intensity, thereby assisting discrimination of small or low- contrast objects. Contrast-regulated unsharp masking enhances differentially shadowed or otherwise low-contrast image regions. Real-time removal of localized hotspots, when combined with automatic histogram equalization, may enhance resolution of objects directly adjacent. In video imagery corrupted by zero-mean noise, real-time frame averaging can assist resolution and location of small or low-contrast objects. To maximize analyst efficiency, lengthy video sequences can be screened automatically for low-frequency, high-magnitude events. Combined zoom, roam, and automatic dynamic range adjustment permit rapid analysis of facial features captured by video cameras recording crimes in progress. When trying to resolve small objects in murky seawater, stereo video places the moving imagery in an optimal setting for human interpretation.

  13. Real-time acquisition and display of flow contrast using speckle variance optical coherence tomography in a graphics processing unit.

    PubMed

    Xu, Jing; Wong, Kevin; Jian, Yifan; Sarunic, Marinko V

    2014-02-01

    In this report, we describe a graphics processing unit (GPU)-accelerated processing platform for real-time acquisition and display of flow contrast images with Fourier domain optical coherence tomography (FDOCT) in mouse and human eyes in vivo. Motion contrast from blood flow is processed using the speckle variance OCT (svOCT) technique, which relies on the acquisition of multiple B-scan frames at the same location and tracking the change of the speckle pattern. Real-time mouse and human retinal imaging using two different custom-built OCT systems with processing and display performed on GPU are presented with an in-depth analysis of performance metrics. The display output included structural OCT data, en face projections of the intensity data, and the svOCT en face projections of retinal microvasculature; these results compare projections with and without speckle variance in the different retinal layers to reveal significant contrast improvements. As a demonstration, videos of real-time svOCT for in vivo human and mouse retinal imaging are included in our results. The capability of performing real-time svOCT imaging of the retinal vasculature may be a useful tool in a clinical environment for monitoring disease-related pathological changes in the microcirculation such as diabetic retinopathy.

  14. Closed-loop control of renal perfusion pressure in physiological experiments.

    PubMed

    Campos-Delgado, D U; Bonilla, I; Rodríguez-Martínez, M; Sánchez-Briones, M E; Ruiz-Hernández, E

    2013-07-01

    This paper presents the design, experimental modeling, and control of a pump-driven renal perfusion pressure (RPP)-regulatory system to implement precise and relatively fast RPP regulation in rats. The mechatronic system is a simple, low-cost, and reliable device to automate the RPP regulation process based on flow-mediated occlusion. Hence, the regulated signal is the RPP measured in the left femoral artery of the rat, and the manipulated variable is the voltage applied to a dc motor that controls the occlusion of the aorta. The control system is implemented in a PC through the LabView software, and a data acquisition board NI USB-6210. A simple first-order linear system is proposed to approximate the dynamics in the experiment. The parameters of the model are chosen to minimize the error between the predicted and experimental output averaged from eight input/output datasets at different RPP operating conditions. A closed-loop servocontrol system based on a pole-placement PD controller plus dead-zone compensation was proposed for this purpose. First, the feedback structure was validated in simulation by considering parameter uncertainty, and constant and time-varying references. Several experimental tests were also conducted to validate in real time the closed-loop performance for stepwise and fast switching references, and the results show the effectiveness of the proposed automatic system to regulate the RPP in the rat, in a precise, accurate (mean error less than 2 mmHg) and relatively fast mode (10-15 s of response time).

  15. Control-oriented modeling and real-time control for the ozone dosing process of drinking water treatment.

    PubMed

    Wang, Dongsheng; Li, Shihua; Zhou, Xingpeng

    2013-03-05

    Ozonation is one of the most important steps during drinking water treatment. To improve the efficiency of ozonation and to stabilize the quality of the treated water, control-oriented modeling and a real-time control method for the ozone dosing process are developed in this study. Compared with existing ozonation models developed by bench-scale and pilot-scale batch experiments, the model reported herein is control-oriented and based on plant-scale batch experiments. A real-time control strategy for maintaining a constant ozone exposure is attempted to meet primary disinfection requirements. An internal model control scheme is proposed to maintain a constant ozone exposure by adjusting the ozone dosage. The proposed real-time control method can cope with changing water quality, water flow rate, and process operational conditions. Both simulations and experimental studies have been carried out and implemented for the ozone dosing process control system, and the results demonstrate the effectiveness and practicality of this real-time control method.

  16. Real-time distributed processing in the Mt. Wilson 100-inch Hooker telescope adaptive optics system

    NASA Astrophysics Data System (ADS)

    Schneider, Thomas G.; Shelton, J. Christopher

    2000-06-01

    The Adoptics software used with the Hooker telescope's ADOPT adaptive optics system implements real-time control on a network of eight Texas Instruments C40 40Mhz DSP processors. System inputs and outputs consist of a 32 port 4 fiber wavefront sensor CCD with 32 X 32 pixels, a tilt mirror and a deformable mirror of which 241 elements are actively controlled. The network os eight DSP processors is configured as two cross-connected rings of four processors each. Four input sites perform intensity and gradient calculations immediately on incoming pixels as well as passing pixels on to adjacent sites for parallel calculations.

  17. Real-time detection and elimination of nonorthogonality error in interference fringe processing.

    PubMed

    Hu, Haijiang; Zhang, Fengdeng

    2011-05-20

    In the measurement system of interference fringe, the nonorthogonality error is a main error source that influences the precision and accuracy of the measurement system. The detection and elimination of the error has been an important target. A novel method that only uses the cross-zero detection and the counting is proposed to detect and eliminate the nonorthogonality error in real time. This method can be simply realized by means of the digital logic device, because it does not invoke trigonometric functions and inverse trigonometric functions. And it can be widely used in the bidirectional subdivision systems of a Moiré fringe and other optical instruments.

  18. Real-time detection and elimination of nonorthogonality error in interference fringe processing

    SciTech Connect

    Hu Haijiang; Zhang Fengdeng

    2011-05-20

    In the measurement system of interference fringe, the nonorthogonality error is a main error source that influences the precision and accuracy of the measurement system. The detection and elimination of the error has been an important target. A novel method that only uses the cross-zero detection and the counting is proposed to detect and eliminate the nonorthogonality error in real time. This method can be simply realized by means of the digital logic device, because it does not invoke trigonometric functions and inverse trigonometric functions. And it can be widely used in the bidirectional subdivision systems of a Moire fringe and other optical instruments.

  19. Real-time image processing for label-free enrichment of Actinobacteria cultivated in picolitre droplets.

    PubMed

    Zang, Emerson; Brandes, Susanne; Tovar, Miguel; Martin, Karin; Mech, Franziska; Horbert, Peter; Henkel, Thomas; Figge, Marc Thilo; Roth, Martin

    2013-09-21

    The majority of today's antimicrobial therapeutics is derived from secondary metabolites produced by Actinobacteria. While it is generally assumed that less than 1% of Actinobacteria species from soil habitats have been cultivated so far, classic screening approaches fail to supply new substances, often due to limited throughput and frequent rediscovery of already known strains. To overcome these restrictions, we implement high-throughput cultivation of soil-derived Actinobacteria in microfluidic pL-droplets by generating more than 600,000 pure cultures per hour from a spore suspension that can subsequently be incubated for days to weeks. Moreover, we introduce triggered imaging with real-time image-based droplet classification as a novel universal method for pL-droplet sorting. Growth-dependent droplet sorting at frequencies above 100 Hz is performed for label-free enrichment and extraction of microcultures. The combination of both cultivation of Actinobacteria in pL-droplets and real-time detection of growing Actinobacteria has great potential in screening for yet unknown species as well as their undiscovered natural products.

  20. Real-time MST radar signal processing using a microcomputer running under FORTH

    NASA Technical Reports Server (NTRS)

    Bowhill, S. A.

    1983-01-01

    Data on power, correlation time, and velocity were obtained at the Urbana radar using microcomputer and a single floppy disk drive. This system includes the following features: (1) measurement of the real and imaginary components of the received signal at 20 altitudes spaced by 1.5 km; (2) coherent integration of these components over a 1/8-s time period; (3) continuous real time display of the height profiles of the two coherently integrated components; (4) real time calculation of the 1 minute averages of the power and autocovariance function up to 6 lags; (5) output of these data to floppy disk once every 2 minutes; (6) display of the 1 minute power profiles while the data are stored to the disk; (7) visual prompting for the operator to change disks when required at the end of each hour of data; and (8) continuous audible indication of the status of the interrupt service routine. Accomplishments were enabled by two developments: the use of a new correlation algorithm and the use of the FORTH language to manage the various low level and high level procedures involved.

  1. Real-time processing of fast-scan cyclic voltammetry (FSCV) data using a field-programmable gate array (FPGA).

    PubMed

    Bozorgzadeh, Bardia; Covey, Daniel P; Heidenreich, Byron A; Garris, Paul A; Mohseni, Pedram

    2014-01-01

    This paper reports the hardware implementation of a digital signal processing (DSP) unit for real-time processing of data obtained by fast-scan cyclic voltammetry (FSCV) at a carbon-fiber microelectrode (CFM), an electrochemical transduction technique for high-resolution monitoring of brain neurochemistry. Implemented on a field-programmable gate array (FPGA), the DSP unit comprises a decimation filter and an embedded processor to process the oversampled FSCV data and obtain in real time a temporal profile of concentration variation along with a chemical signature to identify the target neurotransmitter. Interfaced with an integrated, FSCV-sensing front-end, the DSP unit can successfully process FSCV data obtained by bolus injection of dopamine in a flow cell as well as electrically evoked, transient dopamine release in the dorsal striatum of an anesthetized rat.

  2. Real-Time Processing of Continuous Physiological Signals in a Neurocritical Care Unit on a Stream Data Analytics Platform.

    PubMed

    Bai, Yong; Sow, Daby; Vespa, Paul; Hu, Xiao

    2016-01-01

    Continuous high-volume and high-frequency brain signals such as intracranial pressure (ICP) and electroencephalographic (EEG) waveforms are commonly collected by bedside monitors in neurocritical care. While such signals often carry early signs of neurological deterioration, detecting these signs in real time with conventional data processing methods mainly designed for retrospective analysis has been extremely challenging. Such methods are not designed to handle the large volumes of waveform data produced by bedside monitors. In this pilot study, we address this challenge by building a prototype system using the IBM InfoSphere Streams platform, a scalable stream computing platform, to detect unstable ICP dynamics in real time. The system continuously receives electrocardiographic and ICP signals and analyzes ICP pulse morphology looking for deviations from a steady state. We also designed a Web interface to display in real time the result of this analysis in a Web browser. With this interface, physicians are able to ubiquitously check on the status of their patients and gain direct insight into and interpretation of the patient's state in real time. The prototype system has been successfully tested prospectively on live hospitalized patients.

  3. Azimuth correlator for real-time synthetic aperture radar image processing

    NASA Technical Reports Server (NTRS)

    Arens, W. E. (Inventor)

    1979-01-01

    An azimuth correlator architecture is defined wherein a number of serial range-line buffer memories are cascaded such that the output stages of all buffer memories together form a complete and unique range bin in the azimuthal dimension at any given time. A range bin is automatically read out of the last stages of the registers in parallel on a range line sample-by-sample basis for subsequent range migration correction and correlation. Range migration correction is performed on the range bins by effectively varying the length of a delay register at the output of each range-line buffer memory. The corrected range bin output from the delay registers is then correlated with a Doppler reference function to form an image element on a real-time basis.

  4. Architecture For The Optimization Of A Machining Process In Real Time Through Rule-Based Expert System

    NASA Astrophysics Data System (ADS)

    Serrano, Rafael; González, Luis Carlos; Martín, Francisco Jesús

    2009-11-01

    Under the project SENSOR-IA which has had financial funding from the Order of Incentives to the Regional Technology Centers of the Counsil of Innovation, Science and Enterprise of Andalusia, an architecture for the optimization of a machining process in real time through rule-based expert system has been developed. The architecture consists of an acquisition system and sensor data processing engine (SATD) from an expert system (SE) rule-based which communicates with the SATD. The SE has been designed as an inference engine with an algorithm for effective action, using a modus ponens rule model of goal-oriented rules.The pilot test demonstrated that it is possible to govern in real time the machining process based on rules contained in a SE. The tests have been done with approximated rules. Future work includes an exhaustive collection of data with different tool materials and geometries in a database to extract more precise rules.

  5. Real-time image processing II; Proceedings of the Meeting, Orlando, FL, Apr. 16-18, 1990

    NASA Technical Reports Server (NTRS)

    Juday, Richard D. (Editor)

    1990-01-01

    The present conference discusses topics in the fields of feature extraction and implementation, filter and correlation algorithms, optical correlators, high-level algorithms, and digital image processing for ranging and remote driving. Attention is given to a nonlinear filter derived from topological image features, IR image segmentation through iterative thresholding, orthogonal subspaces for correlation masking, composite filter trees and image recognition via binary search, and features of matrix-coherent optical image processing. Also discussed are multitarget tracking via hybrid joint transform correlator, binary joint Fourier transform correlator considerations, global image processing operations on parallel architectures, real-time implementation of a differential range finder, and real-time binocular stereo range and motion detection.

  6. Performance of a real-time sensor and processing system on a helicopter

    NASA Astrophysics Data System (ADS)

    Kurz, F.; Rosenbaum, D.; Meynberg, O.; Mattyus, G.; Reinartz, P.

    2014-11-01

    A new optical real-time sensor system (4k system) on a helicopter is now ready to use for applications during disasters, mass events and traffic monitoring scenarios. The sensor was developed light-weighted, small with relatively cheap components in a pylon mounted sideward on a helicopter. The sensor architecture is finally a compromise between the required functionality, the development costs, the weight and the sensor size. Aboard processors are integrated in the 4k sensor system for orthophoto generation, for automatic traffic parameter extraction and for data downlinks. It is planned to add real-time processors for person detection and tracking, for DSM generation and for water detection. Equipped with the newest and most powerful off-the-shelf cameras available, a wide variety of viewing configurations with a frame rate of up to 12 Hz for the different applications is possible. Based on three cameras with 50 mm lenses which are looking in different directions, a maximal FOV of 104° is reachable; with 100 mm lenses a ground sampling distance of 3.5 cm is possible at a flight height of 500 m above ground. In this paper, we present the first data sets and describe the technical components of the sensor. The effect of vibrations of the helicopter on the GNSS/IMU accuracy and on the 4k video quality is analysed. It can be shown, that if the helicopter hoovers the rolling shutter effect affects the 4k video quality drastically. The GNSS/IMU error is higher than the specified limit, which is mainly caused by the vibrations on the helicopter and the insufficient vibrational absorbers on the sensor board.

  7. First Results from a Hardware-in-the-Loop Demonstration of Closed-Loop Autonomous Formation Flying

    NASA Technical Reports Server (NTRS)

    Gill, E.; Naasz, Bo; Ebinuma, T.

    2003-01-01

    A closed-loop system for the demonstration of autonomous satellite formation flying technologies using hardware-in-the-loop has been developed. Making use of a GPS signal simulator with a dual radio frequency outlet, the system includes two GPS space receivers as well as a powerful onboard navigation processor dedicated to the GPS-based guidance, navigation, and control of a satellite formation in real-time. The closed-loop system allows realistic simulations of autonomous formation flying scenarios, enabling research in the fields of tracking and orbit control strategies for a wide range of applications. The autonomous closed-loop formation acquisition and keeping strategy is based on Lyapunov's direct control method as applied to the standard set of Keplerian elements. This approach not only assures global and asymptotic stability of the control but also maintains valuable physical insight into the applied control vectors. Furthermore, the approach can account for system uncertainties and effectively avoids a computationally expensive solution of the two point boundary problem, which renders the concept particularly attractive for implementation in onboard processors. A guidance law has been developed which strictly separates the relative from the absolute motion, thus avoiding the numerical integration of a target trajectory in the onboard processor. Moreover, upon using precise kinematic relative GPS solutions, a dynamical modeling or filtering is avoided which provides for an efficient implementation of the process on an onboard processor. A sample formation flying scenario has been created aiming at the autonomous transition of a Low Earth Orbit satellite formation from an initial along-track separation of 800 m to a target distance of 100 m. Assuming a low-thrust actuator which may be accommodated on a small satellite, a typical control accuracy of less than 5 m has been achieved which proves the applicability of autonomous formation flying techniques to

  8. Combining a modified vector field histogram algorithm and real-time image processing for unknown environment navigation

    NASA Astrophysics Data System (ADS)

    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.

  9. Closed Loop Control of Oxygen Delivery and Oxygen Generation

    DTIC Science & Technology

    2017-08-01

    AFRL-SA-WP-SR-2017-0024 Closed Loop Control of Oxygen Delivery and Oxygen Generation Dr. Jay Johannigman1, Richard Branson1...TITLE AND SUBTITLE Closed Loop Control of Oxygen Delivery and Oxygen Generation 5a. CONTRACT NUMBER FA8650-10-2-6140 5b. GRANT NUMBER...humans would be the next step in validating this system. 15. SUBJECT TERMS Closed loop control, oxygen generation , oxygen concentration

  10. Closed-loop quantum control utilizing time domain maps

    NASA Astrophysics Data System (ADS)

    Biteen, Julie S.; Geremia, J. M.; Rabitz, Herschel

    2003-05-01

    Closed-loop laser control of quantum dynamics phenomena may be accomplished through frequency domain manipulations in the laboratory guided by a learning algorithm. This paper presents an alternative method based on the use of nonlinear input→output maps generated in the time domain, although the actual experiments and control optimization are carried out in the frequency domain. The procedure first involves the construction of input→output maps relating the field structure to the observed control performance. These maps are utilized as a substitute for actual experiments in the subsequent optimization stage in order to find the field that drives the system to a specified target. This closed-loop learning process is repeated with a sufficient number of maps until a control field is found that yields the target observable as best as possible. The overall algorithm is simulated with two model quantum systems. It is shown that excellent quality control can be achieved through this sequential learning procedure, even with individual maps that have only modest global accuracy.

  11. Real-time target detection technology of large view-field infrared image based on multicore DSP parallel processing

    NASA Astrophysics Data System (ADS)

    Sun, Gang; Liu, Songlin; Wang, Weihua; Chen, Zengping

    2013-10-01

    In order to implement real-time detection of hedgehopping target in large view-field infrared (LVIR) image, the paper proposes a fast algorithm flow to extract the target region of interest (ROI). The ground building region was rejected quickly and target ROI was segmented roughly through the background classification. Then the background image containing target ROI was matched with previous frame based on a mean removal normalized product correlation (MRNPC) similarity measure function. Finally, the target motion area was extracted by inter-frame difference in time domain. According to the proposed algorithm flow, this paper designs the high-speed real-time signal processing hardware platform based on FPGA + DSP, and also presents a new parallel processing strategy that called function-level and task-level, which could parallel process LVIR image by multi-core and multi-task. Experimental results show that the algorithm can extract low altitude aero target with complex background in large view effectively, and the new design hardware platform could implement real time processing of the IR image with 50000x288 pixels per second in large view-field infrared search system (LVIRSS).

  12. Real-time 2D parallel windowed Fourier transform for fringe pattern analysis using Graphics Processing Unit.

    PubMed

    Gao, Wenjing; Huyen, Nguyen Thi Thanh; Loi, Ho Sy; Kemao, Qian

    2009-12-07

    In optical interferometers, fringe projection systems, and synthetic aperture radars, fringe patterns are common outcomes and usually degraded by unavoidable noises. The presence of noises makes the phase extraction and phase unwrapping challenging. Windowed Fourier transform (WFT) based algorithms have been proven to be effective for fringe pattern analysis to various applications. However, the WFT-based algorithms are computationally expensive, prohibiting them from real-time applications. In this paper, we propose a fast parallel WFT-based library using graphics processing units and computer unified device architecture. Real-time WFT-based algorithms are achieved with 4 frames per second in processing 256x256 fringe patterns. Up to 132x speedup is obtained for WFT-based algorithms using NVIDIA GTX295 graphics card than sequential C in quad-core 2.5GHz Intel(R)Xeon(R) CPU E5420.

  13. A method for closed-loop presentation of sensory stimuli conditional on the internal brain-state of awake animals

    PubMed Central

    Rutishauser, Ueli; Kotowicz, Andreas; Laurent, Gilles

    2013-01-01

    Brain activity often consists of interactions between internal—or on-going—and external—or sensory—activity streams, resulting in complex, distributed patterns of neural activity. Investigation of such interactions could benefit from closed-loop experimental protocols in which one stream can be controlled depending on the state of the other. We describe here methods to present rapid and precisely timed visual stimuli to awake animals, conditional on features of the animal’s on-going brain state; those features are the presence, power and phase of oscillations in local field potentials (LFP). The system can process up to 64 channels in real time. We quantified its performance using simulations, synthetic data and animal experiments (chronic recordings in the dorsal cortex of awake turtles). The delay from detection of an oscillation to the onset of a visual stimulus on an LCD screen was 47.5 ms and visual-stimulus onset could be locked to the phase of ongoing oscillations at any frequency ≤40 Hz. Our software’s architecture is flexible, allowing on-the-fly modifications by experimenters and the addition of new closed-loop control and analysis components through plugins. The source code of our system “StimOMatic” is available freely as open-source. PMID:23473800

  14. A method for closed-loop presentation of sensory stimuli conditional on the internal brain-state of awake animals.

    PubMed

    Rutishauser, Ueli; Kotowicz, Andreas; Laurent, Gilles

    2013-04-30

    Brain activity often consists of interactions between internal-or on-going-and external-or sensory-activity streams, resulting in complex, distributed patterns of neural activity. Investigation of such interactions could benefit from closed-loop experimental protocols in which one stream can be controlled depending on the state of the other. We describe here methods to present rapid and precisely timed visual stimuli to awake animals, conditional on features of the animal's on-going brain state; those features are the presence, power and phase of oscillations in local field potentials (LFP). The system can process up to 64 channels in real time. We quantified its performance using simulations, synthetic data and animal experiments (chronic recordings in the dorsal cortex of awake turtles). The delay from detection of an oscillation to the onset of a visual stimulus on an LCD screen was 47.5ms and visual-stimulus onset could be locked to the phase of ongoing oscillations at any frequency ≤40Hz. Our software's architecture is flexible, allowing on-the-fly modifications by experimenters and the addition of new closed-loop control and analysis components through plugins. The source code of our system "StimOMatic" is available freely as open-source.

  15. Fast, multi-channel real-time processing of signals with microsecond latency using graphics processing units

    NASA Astrophysics Data System (ADS)

    Rath, N.; Kato, S.; Levesque, J. P.; Mauel, M. E.; Navratil, G. A.; Peng, Q.

    2014-04-01

    Fast, digital signal processing (DSP) has many applications. Typical hardware options for performing DSP are field-programmable gate arrays (FPGAs), application-specific integrated DSP chips, or general purpose personal computer systems. This paper presents a novel DSP platform that has been developed for feedback control on the HBT-EP tokamak device. The system runs all signal processing exclusively on a Graphics Processing Unit (GPU) to achieve real-time performance with latencies below 8 μs. Signals are transferred into and out of the GPU using PCI Express peer-to-peer direct-memory-access transfers without involvement of the central processing unit or host memory. Tests were performed on the feedback control system of the HBT-EP tokamak using forty 16-bit floating point inputs and outputs each and a sampling rate of up to 250 kHz. Signals were digitized by a D-TACQ ACQ196 module, processing done on an NVIDIA GTX 580 GPU programmed in CUDA, and analog output was generated by D-TACQ AO32CPCI modules.

  16. Fast, multi-channel real-time processing of signals with microsecond latency using graphics processing units

    SciTech Connect

    Rath, N. Levesque, J. P.; Mauel, M. E.; Navratil, G. A.; Peng, Q.; Kato, S.

    2014-04-15

    Fast, digital signal processing (DSP) has many applications. Typical hardware options for performing DSP are field-programmable gate arrays (FPGAs), application-specific integrated DSP chips, or general purpose personal computer systems. This paper presents a novel DSP platform that has been developed for feedback control on the HBT-EP tokamak device. The system runs all signal processing exclusively on a Graphics Processing Unit (GPU) to achieve real-time performance with latencies below 8 μs. Signals are transferred into and out of the GPU using PCI Express peer-to-peer direct-memory-access transfers without involvement of the central processing unit or host memory. Tests were performed on the feedback control system of the HBT-EP tokamak using forty 16-bit floating point inputs and outputs each and a sampling rate of up to 250 kHz. Signals were digitized by a D-TACQ ACQ196 module, processing done on an NVIDIA GTX 580 GPU programmed in CUDA, and analog output was generated by D-TACQ AO32CPCI modules.

  17. Fast, multi-channel real-time processing of signals with microsecond latency using graphics processing units.

    PubMed

    Rath, N; Kato, S; Levesque, J P; Mauel, M E; Navratil, G A; Peng, Q

    2014-04-01

    Fast, digital signal processing (DSP) has many applications. Typical hardware options for performing DSP are field-programmable gate arrays (FPGAs), application-specific integrated DSP chips, or general purpose personal computer systems. This paper presents a novel DSP platform that has been developed for feedback control on the HBT-EP tokamak device. The system runs all signal processing exclusively on a Graphics Processing Unit (GPU) to achieve real-time performance with latencies below 8 μs. Signals are transferred into and out of the GPU using PCI Express peer-to-peer direct-memory-access transfers without involvement of the central processing unit or host memory. Tests were performed on the feedback control system of the HBT-EP tokamak using forty 16-bit floating point inputs and outputs each and a sampling rate of up to 250 kHz. Signals were digitized by a D-TACQ ACQ196 module, processing done on an NVIDIA GTX 580 GPU programmed in CUDA, and analog output was generated by D-TACQ AO32CPCI modules.

  18. Real-Time Acquisition and Processing System (RTAPS) Version 1.1 Installation and User’s Manual.

    DTIC Science & Technology

    1986-08-01

    acquisition, storage, real-time processing, and graphic display of sensor data (physical, chemical , and biological) and navigation/position information... Alternatively , the recommended method of plotter device specification is to use the AST* superspl package, which provides an internal buffer area for plotter...return>* B> WOS <return> or C> WOS <return> *Depending on the current logged drive WOS may also be executed from an alternate disk volume by entering: A

  19. Implementation of a Quadrature Mirror Filter Bank on an SRC Reconfigurable Computer for Real-Time Signal Processing

    DTIC Science & Technology

    2006-09-01

    7 A. QUADRATURE MIRROR FILTER BANK AS PART OF AN LPI ELINT DETECTION SYSTEM ...implementation for a real-time Quadrature Mirror Filter Bank on an SRC-6 reconfigurable computer system . A Quadrature Mirror Filter (QMF) Bank is a type...of wavelet decomposition filter system used for Digital Signal Processing (DSP). The use of a Quadrature Mirror Filter Bank as part of a larger

  20. Massively Parallel Signal Processing using the Graphics Processing Unit for Real-Time Brain–Computer Interface Feature Extraction

    PubMed Central

    Wilson, J. Adam; Williams, Justin C.

    2009-01-01

    The clock speeds of modern computer processors have nearly plateaued in the past 5 years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a graphics card [graphics processing unit (GPU)] was developed for real-time neural signal processing of a brain–computer interface (BCI). The NVIDIA CUDA system was used to offload processing to the GPU, which is capable of running many operations in parallel, potentially greatly increasing the speed of existing algorithms. The BCI system records many channels of data, which are processed and translated into a control signal, such as the movement of a computer cursor. This signal processing chain involves computing a matrix–matrix multiplication (i.e., a spatial filter), followed by calculating the power spectral density on every channel using an auto-regressive method, and finally classifying appropriate features for control. In this study, the first two computationally intensive steps were implemented on the GPU, and the speed was compared to both the current implementation and a central processing unit-based implementation that uses multi-threading. Significant performance gains were obtained with GPU processing: the current implementation processed 1000 channels of 250 ms in 933 ms, while the new GPU method took only 27 ms, an improvement of nearly 35 times. PMID:19636394

  1. Massively Parallel Signal Processing using the Graphics Processing Unit for Real-Time Brain-Computer Interface Feature Extraction.

    PubMed

    Wilson, J Adam; Williams, Justin C

    2009-01-01

    The clock speeds of modern computer processors have nearly plateaued in the past 5 years. Consequently, neural prosthetic systems that rely on processing large quantities of data in a short period of time face a bottleneck, in that it may not be possible to process all of the data recorded from an electrode array with high channel counts and bandwidth, such as electrocorticographic grids or other implantable systems. Therefore, in this study a method of using the processing capabilities of a graphics card [graphics processing unit (GPU)] was developed for real-time neural signal processing of a brain-computer interface (BCI). The NVIDIA CUDA system was used to offload processing to the GPU, which is capable of running many operations in parallel, potentially greatly increasing the speed of existing algorithms. The BCI system records many channels of data, which are processed and translated into a control signal, such as the movement of a computer cursor. This signal processing chain involves computing a matrix-matrix multiplication (i.e., a spatial filter), followed by calculating the power spectral density on every channel using an auto-regressive method, and finally classifying appropriate features for control. In this study, the first two computationally intensive steps were implemented on the GPU, and the speed was compared to both the current implementation and a central processing unit-based implementation that uses multi-threading. Significant performance gains were obtained with GPU processing: the current implementation processed 1000 channels of 250 ms in 933 ms, while the new GPU method took only 27 ms, an improvement of nearly 35 times.

  2. Real-time processing of ASL signs: Delayed first language acquisition affects organization of the mental lexicon.

    PubMed

    Lieberman, Amy M; Borovsky, Arielle; Hatrak, Marla; Mayberry, Rachel I

    2015-07-01

    Sign language comprehension requires visual attention to the linguistic signal and visual attention to referents in the surrounding world, whereas these processes are divided between the auditory and visual modalities for spoken language comprehension. Additionally, the age-onset of first language acquisition and the quality and quantity of linguistic input for deaf individuals is highly heterogeneous, which is rarely the case for hearing learners of spoken languages. Little is known about how these modality and developmental factors affect real-time lexical processing. In this study, we ask how these factors impact real-time recognition of American Sign Language (ASL) signs using a novel adaptation of the visual world paradigm in deaf adults who learned sign from birth (Experiment 1), and in deaf adults who were late-learners of ASL (Experiment 2). Results revealed that although both groups of signers demonstrated rapid, incremental processing of ASL signs, only native signers demonstrated early and robust activation of sublexical features of signs during real-time recognition. Our findings suggest that the organization of the mental lexicon into units of both form and meaning is a product of infant language learning and not the sensory and motor modality through which the linguistic signal is sent and received. (c) 2015 APA, all rights reserved.

  3. Real-time processing of ASL signs: Delayed first language acquisition affects organization of the mental lexicon

    PubMed Central

    Lieberman, Amy M.; Borovsky, Arielle; Hatrak, Marla; Mayberry, Rachel I.

    2014-01-01

    Sign language comprehension requires visual attention to the linguistic signal and visual attention to referents in the surrounding world, whereas these processes are divided between the auditory and visual modalities for spoken language comprehension. Additionally, the age-onset of first language acquisition and the quality and quantity of linguistic input and for deaf individuals is highly heterogeneous, which is rarely the case for hearing learners of spoken languages. Little is known about how these modality and developmental factors affect real-time lexical processing. In this study, we ask how these factors impact real-time recognition of American Sign Language (ASL) signs using a novel adaptation of the visual world paradigm in deaf adults who learned sign from birth (Experiment 1), and in deaf individuals who were late-learners of ASL (Experiment 2). Results revealed that although both groups of signers demonstrated rapid, incremental processing of ASL signs, only native-signers demonstrated early and robust activation of sub-lexical features of signs during real-time recognition. Our findings suggest that the organization of the mental lexicon into units of both form and meaning is a product of infant language learning and not the sensory and motor modality through which the linguistic signal is sent and received. PMID:25528091

  4. Process modeling and control applied to real-time monitoring of distillation processes by near-infrared spectroscopy.

    PubMed

    de Oliveira, Rodrigo R; Pedroza, Ricardo H P; Sousa, A O; Lima, Kássio M G; de Juan, Anna

    2017-09-08

    A distillation device that acquires continuous and synchronized measurements of temperature, percentage of distilled fraction and NIR spectra has been designed for real-time monitoring of distillation processes. As a process model, synthetic commercial gasoline batches produced in Brazil, which contain mixtures of pure gasoline blended with ethanol have been analyzed. The information provided by this device, i.e., distillation curves and NIR spectra, has served as initial information for the proposal of new strategies of process modeling and multivariate statistical process control (MSPC). Process modeling based on PCA batch analysis provided global distillation trajectories, whereas multiset MCR-ALS analysis is proposed to obtain a component-wise characterization of the distillation evolution and distilled fractions. Distillation curves, NIR spectra or compressed NIR information under the form of PCA scores and MCR-ALS concentration profiles were tested as the seed information to build MSPC models. New on-line PCA-based MSPC approaches, some inspired on local rank exploratory methods for process analysis, are proposed and work as follows: a) MSPC based on individual process observation models, where multiple local PCA models are built considering the sole information in each observation point; b) Fixed Size Moving Window - MSPC, in which local PCA models are built considering a moving window of the current and few past observation points; and c) Evolving MSPC, where local PCA models are built with an increasing window of observations covering all points since the beginning of the process until the current observation. Performance of different approaches has been assessed in terms of sensitivity to fault detection and number of false alarms. The outcome of this work will be of general use to define strategies for on-line process monitoring and control and, in a more specific way, to improve quality control of petroleum derived fuels and other substances submitted

  5. A cohesive modular system for real-time stereoscopic secure image processing and evaluation

    NASA Astrophysics Data System (ADS)

    Galli, Raffaello; Lazarus, Ed

    2007-02-01

    In this paper we define an innovative modular real-time system to visualize, capture, manage, securely preserve, store and playback stereoscopic images. The system, called "Solid-Look" together with the cameras "StereOpsis" will allow military, EOD specialists, and private industry operators to literally "see through the robot's eyes". The system enables the operator to control the robot as if his/her head were located on the robot itself, positioning and zooming the camera to the visual target object using the operator's eye and head movement, without any wearable devices and allowing the operator's hands to perform other tasks. The stereo cameras perform zooming and image stabilization for a controlled and smooth vision. The display enables stereoscopic vision without the need of glasses. Every image frame is authenticated, encrypted and timestamped to allow certainty and confidentiality during post-capture playback or to show evidence in court. The system secures the ability to operate it, requiring administrator's biometrical authentication. Solid-Look modular design can be used in multiple industries from Homeland Security to Pharmaceutical including research, forensic and underwater inspections and will certainly provide great benefit to the performance, speed and accuracy of the operations.

  6. Detection by real time PCR of walnut allergen coding sequences in processed foods.

    PubMed

    Linacero, Rosario; Ballesteros, Isabel; Sanchiz, Africa; Prieto, Nuria; Iniesto, Elisa; Martinez, Yolanda; Pedrosa, Mercedes M; Muzquiz, Mercedes; Cabanillas, Beatriz; Rovira, Mercè; Burbano, Carmen; Cuadrado, Carmen

    2016-07-01

    A quantitative real-time PCR (RT-PCR) method, employing novel primer sets designed on Jug r 1, Jug r 3, and Jug r 4 allergen-coding sequences, was set up and validated. Its specificity, sensitivity, and applicability were evaluated. The DNA extraction method based on CTAB-phenol-chloroform was best for walnut. RT-PCR allowed a specific and accurate amplification of allergen sequence, and the limit of detection was 2.5pg of walnut DNA. The method sensitivity and robustness were confirmed with spiked samples, and Jug r 3 primers detected up to 100mg/kg of raw walnut (LOD 0.01%, LOQ 0.05%). Thermal treatment combined with pressure (autoclaving) reduced yield and amplification (integrity and quality) of walnut DNA. High hydrostatic pressure (HHP) did not produce any effect on the walnut DNA amplification. This RT-PCR method showed greater sensitivity and reliability in the detection of walnut traces in commercial foodstuffs compared with ELISA assays.

  7. Profiling Real-Time Electricity Consumption Data for Process Monitoring and Control

    SciTech Connect

    Omitaomu, Olufemi A

    2013-01-01

    Today, smart meters serve as key assets to utilities and their customers because they are capable of recording and communicating real-time energy usage data; thus, enabling better understanding of energy usage patterns. Other potential benefits of smart meters data include the ability to improve customer experience, grid reliability, outage management, and operational efficiency. Despite these tangible benefits, many utilities are inundated by data and remain uncertain about how to extract additional value from these deployed assets outside of billing operations. One way to overcome this challenge is the development of new metrics for classifying utility customers. Traditionally, utilities classified their customers based on their business nature (residential, commercial, and industrial) and/or their total annual consumption. While this classification is useful for some operational functions, it is too limited for designing effective monitoring and control strategies. In this paper, a data mining methodology is proposed for clustering and profiling smart meters data in order to form unique classes of customers exhibiting similar usage patterns. The developed clusters could help utilities in identifying opportunities for achieving some of the benefits of smart meters data.

  8. Advancement of Solidification Processing Technology Through Real Time X-Ray Transmission Microscopy: Sample Preparation

    NASA Technical Reports Server (NTRS)

    Stefanescu, D. M.; Curreri, P. A.

    1996-01-01

    Two types of samples were prepared for the real time X-ray transmission microscopy (XTM) characterization. In the first series directional solidification experiments were carried out to evaluate the critical velocity of engulfment of zirconia particles in the Al and Al-Ni eutectic matrix under ground (l-g) conditions. The particle distribution in the samples was recorded on video before and after the samples were directionally solidified. In the second series samples of the above two type of composites were prepared for directional solidification runs to be carried out on the Advanced Gradient Heating Facility (AGHF) aboard the space shuttle during the LMS mission in June 1996. X-ray microscopy proved to be an invaluable tool for characterizing the particle distribution in the metal matrix samples. This kind of analysis helped in determining accurately the critical velocity of engulfment of ceramic particles by the melt interface in the opaque metal matrix composites. The quality of the cast samples with respect to porosity and instrumented thermocouple sheath breakage or shift could be easily viewed and thus helped in selecting samples for the space shuttle experiments. Summarizing the merits of this technique it can be stated that this technique enabled the use of cast metal matrix composite samples since the particle location was known prior to the experiment.

  9. Color reproduction and processing algorithm based on real-time mapping for endoscopic images.

    PubMed

    Khan, Tareq H; Mohammed, Shahed K; Imtiaz, Mohammad S; Wahid, Khan A

    2016-01-01

    In this paper, we present a real-time preprocessing algorithm for image enhancement for endoscopic images. A novel dictionary based color mapping algorithm is used for reproducing the color information from a theme image. The theme image is selected from a nearby anatomical location. A database of color endoscopy image for different location is prepared for this purpose. The color map is dynamic as its contents change with the change of the theme image. This method is used on low contrast grayscale white light images and raw narrow band images to highlight the vascular and mucosa structures and to colorize the images. It can also be applied to enhance the tone of color images. The statistic visual representation and universal image quality measures show that the proposed method can highlight the mucosa structure compared to other methods. The color similarity has been verified using Delta E color difference, structure similarity index, mean structure similarity index and structure and hue similarity. The color enhancement was measured using color enhancement factor that shows considerable improvements. The proposed algorithm has low and linear time complexity, which results in higher execution speed than other related works.

  10. Multi-purpose fast neutron spectrum analyzer with real-time signal processing

    NASA Astrophysics Data System (ADS)

    Sulyaev, Yu. S.; Puryga, E. A.; Khilchenko, A. D.; Kvashnin, A. N.; Polosatkin, S. V.; Rovenskikh, A. F.; Burdakov, A. V.; Grishnyaev, E. V.

    2013-08-01

    Diagnostics of hot ion component of plasma on the products of fusion reactions is widely used on thermonuclear facilities. In case of employment of neutron spectrometers, based on organics scintillators, there is advanced technique developed to eliminate neutron pulses from gamma background—digital pulse shape discrimination. For every DPSD application it is necessary to use the fast (2-5 ns) and precise (12 bit) transient ADC unit with large amount of onboard memory for storing every digitized scintillation pulses during shot time. At present time the duration of hot thermonuclear plasma burning in large tokamaks approximate to 1 min, and this requires very high onboard memory capacity (˜100 GB). This paper describes a neutron spectrum analyzer with real-time DPSD algorithm, implemented to ADC unit. This approach saves about two orders of onboard memory capacity, gives the possibility of instant use of outcome to feedback systems. This analyzer was tested and calibrated with help of 60Co and 252Cf radiation sources, and deuterium neutron generator.

  11. An intestinal surgery simulator: real-time collision processing and visualization.

    PubMed

    Raghupathi, Laks; Grisoni, Laurent; Faure, François; Marchal, Damien; Cani, Marie-Paule; Chaillou, Christophe

    2004-01-01

    This research work is aimed toward the development of a VR-based trainer for colon cancer removal. It enables the surgeons to interactively view and manipulate the concerned virtual organs as during a real surgery. First, we present a method for animating the small intestine and the mesentery (the tissue that connects it to the main vessels) in real-time, thus enabling user interaction through virtual surgical tools during the simulation. We present a stochastic approach for fast collision detection in highly deformable, self-colliding objects. A simple and efficient response to collisions is also introduced in order to reduce the overall animation complexity. Second, we describe a new method based on generalized cylinders for fast rendering of the intestine. An efficient curvature detection method, along with an adaptive sampling algorithm, is presented. This approach, while providing improved tessellation without the classical self-intersection problem, also allows for high-performance rendering thanks to the new 3D skinning feature available in recent GPUs. The rendering algorithm is also designed to ensure a guaranteed frame rate. Finally, we present the quantitative results of the simulations and describe the qualitative feedback obtained from the surgeons.

  12. Real-time portable dual channel image fusion and data processing system

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Yang, Yong-ying; Wang, Dao-dang; Liu, Dong

    2009-05-01

    Presently electricity utilities make use of a number of inspection tools to survey their transmission lines and electrical distribution equipment. Visible and ultraviolet cameras are the latest visual diagnostic tools available to utilities to identify potential failures on electrical equipment. Based on the DSP and FPGA hardware platform, a system is designed to collect images from both visible and ultraviolet channels. Moreover, it performs image fusion, characteristic enhancement and image analysis as well. For detecting the corona, a ultra-violet quantum detector is used in the form of an image intensifier tube with a Cesium-Telluride photocathode, which is competent for single photon counting. For acquiring visible images, a high-speed industrial CCD is implemented to assure definition of images in terms of 1394 protocol. The real-time images is displayed on a LCD, compressed and saved for further analysis. Finally, several methods of program debugging are introduced. The experimental results in the field show that the designed system has good performance in the detection of corona radiation.

  13. Real time image processing: Concepts and technologies; Proceedings of the Meeting, Cannes, France, Nov. 17, 18, 1987

    SciTech Connect

    Besson, J.

    1988-01-01

    The conference presents papers on architectures for hybrid and optical processing, image processing and analysis, and modelization-artificial vision-processing for robots. Consideration is given to a prototype of an adaptive optical system for astronomical observation, the influennce of the choice of expansion center on the rotationally invariant correlation filter performance, and a matched filter for IR background suppression. Other topics include progress in real-time image processing for target detection, target tracking, and seeker heads; stereo vision by pyramidal BLI graph matching; and the modeling of a natural three-dimensional scene consisting of moving objects from a sequence of monocular TV images.

  14. Real-Time Parameter Estimation Method Applied to a MIMO Process and its Comparison with an Offline Identification Method

    SciTech Connect

    Kaplanoglu, Erkan; Safak, Koray K.; Varol, H. Selcuk

    2009-01-12

    An experiment based method is proposed for parameter estimation of a class of linear multivariable systems. The method was applied to a pressure-level control process. Experimental time domain input/output data was utilized in a gray-box modeling approach. Prior knowledge of the form of the system transfer function matrix elements is assumed to be known. Continuous-time system transfer function matrix parameters were estimated in real-time by the least-squares method. Simulation results of experimentally determined system transfer function matrix compare very well with the experimental results. For comparison and as an alternative to the proposed real-time estimation method, we also implemented an offline identification method using artificial neural networks and obtained fairly good results. The proposed methods can be implemented conveniently on a desktop PC equipped with a data acquisition board for parameter estimation of moderately complex linear multivariable systems.

  15. A real-time autostereoscopic display method based on partial sub-pixel by general GPU processing

    NASA Astrophysics Data System (ADS)

    Chen, Duo; Sang, Xinzhu; Cai, Yuanfa

    2013-08-01

    With the progress of 3D technology, the huge computing capacity for the real-time autostereoscopic display is required. Because of complicated sub-pixel allocating, masks providing arranged sub-pixels are fabricated to reduce real-time computation. However, the binary mask has inherent drawbacks. In order to solve these problems, weighted masks are used in displaying based on partial sub-pixel. Nevertheless, the corresponding computations will be tremendously growing and unbearable for CPU. To improve calculating speed, Graphics Processing Unit (GPU) processing with parallel computing ability is adopted. Here the principle of partial sub-pixel is presented, and the texture array of Direct3D 10 is used to increase the number of computable textures. When dealing with a HD display and multi-viewpoints, a low level GPU is still able to permit a fluent real time displaying, while the performance of high level CPU is really not acceptable. Meanwhile, after using texture array, the performance of D3D10 could be double, and sometimes be triple faster than D3D9. There are several distinguishing features for the proposed method, such as the good portability, less overhead and good stability. The GPU display system could also be used for the future Ultra HD autostereoscopic display.

  16. On-site identification of meat species in processed foods by a rapid real-time polymerase chain reaction system.

    PubMed

    Furutani, Shunsuke; Hagihara, Yoshihisa; Nagai, Hidenori

    2017-09-01

    Correct labeling of foods is critical for consumers who wish to avoid a specific meat species for religious or cultural reasons. Therefore, gene-based point-of-care food analysis by real-time Polymerase Chain Reaction (PCR) is expected to contribute to the quality control in the food industry. In this study, we perform rapid identification of meat species by our portable rapid real-time PCR system, following a very simple DNA extraction method. Applying these techniques, we correctly identified beef, pork, chicken, rabbit, horse, and mutton in processed foods in 20min. Our system was sensitive enough to detect the interfusion of about 0.1% chicken egg-derived DNA in a processed food sample. Our rapid real-time PCR system is expected to contribute to the quality control in food industries because it can be applied for the identification of meat species, and future applications can expand its functionality to the detection of genetically modified organisms or mutations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. [Real-time automatic cloud detection during the process of taking aerial photographs].

    PubMed

    Gao, Xian-Jun; Wan, You-Chuan; Zheng, Shun-Yi; Yang, Yuan-Wei

    2014-07-01

    The present paper adopted a method based on the spectrum signatures with thresholds to detect cloud. Through analyzing the characteristic in the aspect of spectrum signatures of cloud, two effective signatures were explored, one was brightness signature I and the other was normalized difference signature P. Combined with corresponding thresholds, each spectrum condition can detect some cloud pixels. By composing the union of two spectrum conditions together, cloud can be detected more completely. In addition, the threshold was also very important to the accuracy of the detection result. In order to detect cloud efficiently, correctly and automatically, this paper proposed a new strategy about the assignment of thresholds to acquire suitable thresholds. Firstly, the images should be classified into three kinds of types which were images with no cloud, with thin cloud and with thick cloud. Secondly, different assignment methods of automatic thresholds of signatures would be adopted according to different types of images. For images with thick cloud, they would be further classified into three kinds by another standard and assigned by different thresholds integrated by automatic thresholds from other spectrum signatures. The automatic thresholds were acquired by Otsu algorithm and an improved Otsu algorithm. For images with thin cloud, the cloud would be detected by score algorithm. Due to this flexible strategy, cloud in images can be detected rightly and if there isn't cloud in images the detection will be null to show that there is no cloud. Compared to the detection results of other different methods, the contrast results show that the efficiency of the detection method proposed in this paper is high and the accuracy satisfies the demand of real-time evaluation and the application range is wider.

  18. A Closed-loop Brain Computer Interface to a Virtual Reality Avatar: Gait Adaptation to Visual Kinematic Perturbations

    PubMed Central

    Luu, Trieu Phat; He, Yongtian; Brown, Samuel; Nakagome, Sho; Contreras-Vidal, Jose L.

    2016-01-01

    The control of human bipedal locomotion is of great interest to the field of lower-body brain computer interfaces (BCIs) for rehabilitation of gait. While the feasibility of a closed-loop BCI system for the control of a lower body exoskeleton has been recently shown, multi-day closed-loop neural decoding of human gait in a virtual reality (BCI-VR) environment has yet to be demonstrated. In this study, we propose a real-time closed-loop BCI that decodes lower limb joint angles from scalp electroencephalography (EEG) during treadmill walking to control the walking movements of a virtual avatar. Moreover, virtual kinematic perturbations resulting in asymmetric walking gait patterns of the avatar were also introduced to investigate gait adaptation using the closed-loop BCI-VR system over a period of eight days. Our results demonstrate the feasibility of using a closed-loop BCI to learn to control a walking avatar under normal and altered visuomotor perturbations, which involved cortical adaptations. These findings have implications for the development of BCI-VR systems for gait rehabilitation after stroke and for understanding cortical plasticity induced by a closed-loop BCI system. PMID:27713915

  19. Modular Closed-Loop Control of Diabetes

    PubMed Central

    Magni, L.; Dassau, E.; Hughes-Karvetski, C.; Toffanin, C.; De Nicolao, G.; Del Favero, S.; Breton, M.; Man, C. Dalla; Renard, E.; Zisser, H.; Doyle, F. J.; Cobelli, C.; Kovatchev, B. P.

    2015-01-01

    Modularity plays a key role in many engineering systems, allowing for plug-and-play integration of components, enhancing flexibility and adaptability, and facilitating standardization. In the control of diabetes, i.e., the so-called “artificial pancreas,” modularity allows for the step-wise introduction of (and regulatory approval for) algorithmic components, starting with subsystems for assured patient safety and followed by higher layer components that serve to modify the patient’s basal rate in real time. In this paper, we introduce a three-layer modular architecture for the control of diabetes, consisting in a sensor/pump interface module (IM), a continuous safety module (CSM), and a real-time control module (RTCM), which separates the functions of insulin recommendation (postmeal insulin for mitigating hyperglycemia) and safety (prevention of hypoglycemia). In addition, we provide details of instances of all three layers of the architecture: the APS© serving as the IM, the safety supervision module (SSM) serving as the CSM, and the range correction module (RCM) serving as the RTCM. We evaluate the performance of the integrated system via in silico preclinical trials, demonstrating 1) the ability of the SSM to reduce the incidence of hypoglycemia under nonideal operating conditions and 2) the ability of the RCM to reduce glycemic variability. PMID:22481809

  20. Multiday Fully Closed Loop Insulin Delivery in Monitored Outpatient Conditions

    ClinicalTrials.gov

    2014-04-29

    To Demonstrate That the Closed Loop System Can be Used Safely Over a Few Consecutive Days.; To Assess Effectiveness in Maintaining Patients' Glucose Levels in the Target Range of 70 to 180 mg/dl, Measured by Blood Glucose Sensor.; To Evaluate the User Experience With a Closed Loop System

  1. I-WFM for Real-Time C4I Process Management

    DTIC Science & Technology

    2003-12-01

    Library Core Object Services Java-based Process Composition GUI Process Design and Analysis Java-based Process Analysis GUI Java-based Process... process analysis (PERT Critical Path, deadlock/livelock analysis with Petri Nets, synchronization matrix) • collaboration support C4ISR APPLICATIONS...location knowledge engineering; b) process definition; c) verification; d) visualization with “drill down” and “roll up;” and e) process analysis in

  2. Androgynous, Reconfigurable Closed Loop Feedback Controlled Low Impact Docking System With Load Sensing Electromagnetic Capture Ring

    NASA Technical Reports Server (NTRS)

    Lewis, James L. (Inventor); Carroll, Monty B. (Inventor); Morales, Ray H. (Inventor); Le, Thang D. (Inventor)

    2002-01-01

    The present invention relates to a fully androgynous, reconfigurable closed loop feedback controlled low impact docking system with load sensing electromagnetic capture ring. The docking system of the present invention preferably comprises two Docking- assemblies, each docking assembly comprising a load sensing ring having an outer face, one of more electromagnets, one or more load cells coupled to said load sensing ring. The docking assembly further comprises a plurality of actuator arms coupled to said load sensing ring and capable of dynamically adjusting the orientation of said load sensing ring and a reconfigurable closed loop control system capable of analyzing signals originating from said plurality of load cells and of outputting real time control for each of the actuators. The docking assembly of the present invention incorporates an active load sensing system to automatically dynamically adjust the load sensing ring during capture instead of requiring significant force to push and realign the ring.

  3. A Closed Loop Brain-machine Interface for Epilepsy Control Using Dorsal Column Electrical Stimulation

    PubMed Central

    Pais-Vieira, Miguel; Yadav, Amol P.; Moreira, Derek; Guggenmos, David; Santos, Amílcar; Lebedev, Mikhail; Nicolelis, Miguel A. L.

    2016-01-01

    Although electrical neurostimulation has been proposed as an alternative treatment for drug-resistant cases of epilepsy, current procedures such as deep brain stimulation, vagus, and trigeminal nerve stimulation are effective only in a fraction of the patients. Here we demonstrate a closed loop brain-machine interface that delivers electrical stimulation to the dorsal column (DCS) of the spinal cord to suppress epileptic seizures. Rats were implanted with cortical recording microelectrodes and spinal cord stimulating electrodes, and then injected with pentylenetetrazole to induce seizures. Seizures were detected in real time from cortical local field potentials, after which DCS was applied. This method decreased seizure episode frequency by 44% and seizure duration by 38%. We argue that the therapeutic effect of DCS is related to modulation of cortical theta waves, and propose that this closed-loop interface has the potential to become an effective and semi-invasive treatment for refractory epilepsy and other neurological disorders. PMID:27605389

  4. Closed-Loop Control of Chemical Injection Rate for a Direct Nozzle Injection System

    PubMed Central

    Cai, Xiang; Walgenbach, Martin; Doerpmond, Malte; Schulze Lammers, Peter; Sun, Yurui

    2016-01-01

    To realize site-specific and variable-rate application of agricultural pesticides, accurately metering and controlling the chemical injection rate is necessary. This study presents a prototype of a direct nozzle injection system (DNIS) by which chemical concentration transport lag was greatly reduced. In this system, a rapid-reacting solenoid valve (RRV) was utilized for injecting chemicals, driven by a pulse-width modulation (PWM) signal at 100 Hz, so with varying pulse width the chemical injection rate could be adjusted. Meanwhile, a closed-loop control strategy, proportional-integral-derivative (PID) method, was applied for metering and stabilizing the chemical injection rate. In order to measure chemical flow rates and input them into the controller as a feedback in real-time, a thermodynamic flowmeter that was independent of chemical viscosity was used. Laboratory tests were conducted to assess the performance of DNIS and PID control strategy. Due to the nonlinear input–output characteristics of the RRV, a two-phase PID control process obtained better effects as compared with single PID control strategy. Test results also indicated that the set-point chemical flow rate could be achieved within less than 4 s, and the output stability was improved compared to the case without control strategy. PMID:26805833

  5. Closed-Loop Control of Chemical Injection Rate for a Direct Nozzle Injection System.

    PubMed

    Cai, Xiang; Walgenbach, Martin; Doerpmond, Malte; Schulze Lammers, Peter; Sun, Yurui

    2016-01-20

    To realize site-specific and variable-rate application of agricultural pesticides, accurately metering and controlling the chemical injection rate is necessary. This study presents a prototype of a direct nozzle injection system (DNIS) by which chemical concentration transport lag was greatly reduced. In this system, a rapid-reacting solenoid valve (RRV) was utilized for injecting chemicals, driven by a pulse-width modulation (PWM) signal at 100 Hz, so with varying pulse width the chemical injection rate could be adjusted. Meanwhile, a closed-loop control strategy, proportional-integral-derivative (PID) method, was applied for metering and stabilizing the chemical injection rate. In order to measure chemical flow rates and input them into the controller as a feedback in real-time, a thermodynamic flowmeter that was independent of chemical viscosity was used. Laboratory tests were conducted to assess the performance of DNIS and PID control strategy. Due to the nonlinear input-output characteristics of the RRV, a two-phase PID control process obtained better effects as compared with single PID control strategy. Test results also indicated that the set-point chemical flow rate could be achieved within less than 4 s, and the output stability was improved compared to the case without control strategy.

  6. Digital CODEC for real-time processing of broadcast quality video signals at 1.8 bits/pixel

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Mary JO; Whyte, Wayne A.

    1991-01-01

    Advances in very large scale integration and recent work in the field of bandwidth efficient digital modulation techniques have combined to make digital video processing technically feasible an potentially cost competitive for broadcast quality television transmission. A hardware implementation was developed for DPCM (differential pulse code midulation)-based digital television bandwidth compression algorithm which processes standard NTSC composite color television signals and produces broadcast quality video in real time at an average of 1.8 bits/pixel. The data compression algorithm and the hardware implementation of the codec are described, and performance results are provided.

  7. Digital CODEC for real-time processing of broadcast quality video signals at 1.8 bits/pixel

    NASA Technical Reports Server (NTRS)

    Shalkhauser, Mary JO; Whyte, Wayne A., Jr.

    1989-01-01

    Advances in very large-scale integration and recent work in the field of bandwidth efficient digital modulation techniques have combined to make digital video processing technically feasible and potentially cost competitive for broadcast quality television transmission. A hardware implementation was developed for a DPCM-based digital television bandwidth compression algorithm which processes standard NTSC composite color television signals and produces broadcast quality video in real time at an average of 1.8 bits/pixel. The data compression algorithm and the hardware implementation of the CODEC are described, and performance results are provided.

  8. Developing an EEG-based on-line closed-loop lapse detection and mitigation system

    PubMed Central

    Wang, Yu-Te; Huang, Kuan-Chih; Wei, Chun-Shu; Huang, Teng-Yi; Ko, Li-Wei; Lin, Chin-Teng; Cheng, Chung-Kuan; Jung, Tzyy-Ping

    2014-01-01

    In America, 60% of adults reported that they have driven a motor vehicle while feeling drowsy, and at least 15–20% of fatal car accidents are fatigue-related. This study translates previous laboratory-oriented neurophysiological research to design, develop, and test an On-line Closed-loop Lapse Detection and Mitigation (OCLDM) System featuring a mobile wireless dry-sensor EEG headgear and a cell-phone based real-time EEG processing platform. Eleven subjects participated in an event-related lane-keeping task, in which they were instructed to manipulate a randomly deviated, fixed-speed cruising car on a 4-lane highway. This was simulated in a 1st person view with an 8-screen and 8-projector immersive virtual-reality environment. When the subjects experienced lapses or failed to respond to events during the experiment, auditory warning was delivered to rectify the performance decrements. However, the arousing auditory signals were not always effective. The EEG spectra exhibited statistically significant differences between effective and ineffective arousing signals, suggesting that EEG spectra could be used as a countermeasure of the efficacy of arousing signals. In this on-line pilot study, the proposed OCLDM System was able to continuously detect EEG signatures of fatigue, deliver arousing warning to subjects suffering momentary cognitive lapses, and assess the efficacy of the warning in near real-time to rectify cognitive lapses. The on-line testing results of the OCLDM System validated the efficacy of the arousing signals in improving subjects' response times to the subsequent lane-departure events. This study may lead to a practical on-line lapse detection and mitigation system in real-world environments. PMID:25352773

  9. Implementation of a data processing platform for real-time distance measurement with dual-comb lasers

    NASA Astrophysics Data System (ADS)

    Ni, Kai; Xu, Mingfei; Zhou, Qian; Dong, Hao; Li, Xinghui; Wu, Guanhao

    2015-08-01

    Absolute distance measurement with dual femtosecond comb lasers has advantages of wide-range, high-accuracy and fast speed. It combines time-of-flight and interferometric measurement. The novelty of ranging method leads to new challenges in designing the data acquisition and processing hardware system. Currently there are no available real-time data processing system for dual-comb ranging. This paper introduces our recent progress on designing and implementing such a platform. Our platform mainly contains four different function modules. First, a clock module that accept a 250MHz maximum reference clock input was introduced to generate the sample clock for A/D converter, and the module's output clock can be delayed up to 20ns with a resolution of 714ps. Second, a high-speed data acquisition module with a 14-bit resolution and a 125 MSPS maximum sample rate was designed to convert the analog laser pulse signal to digital signal. Third, we built a real-time data processing module that allows an input of 16-bit data in the FPGA to calculate the distance from the digital signal within 83us. Finally, a data transmission module based on a 128MB DDR SDRAM and USB2.0 was added so that we can easily debug the platform in the PC. The performance of our system is evaluated in real-time. The test bench consists of two femtosecond laser sources, an optical fiber interferometer and our data processing system. The repetition frequencies of the two combs are around 50MHz, with frequency difference of 2.5kHz. The center wavelength of laser pulses is 1560nm. The target distance is from 0m to 3m. The experimental results show that our system can output measurement results at the rate of 2500 pts/s, and the measurement deviation is less than 10um.

  10. The Impact of Number Mismatch and Passives on the Real-Time Processing of Relative Clauses

    ERIC Educational Resources Information Center

    Contemori, Carla; Marinis, Theodoros

    2014-01-01

    Language processing plays a crucial role in language development, providing the ability to assign structural representations to input strings (e.g., Fodor, 1998). In this paper we aim at contributing to the study of children's processing routines, examining the operations underlying the auditory processing of relative clauses in children…

  11. A Flexible Pilot-Scale Setup for Real-Time Studies in Process Systems Engineering

    ERIC Educational Resources Information Center

    Panjapornpon, Chanin; Fletcher, Nathan; Soroush, Masoud

    2006-01-01

    This manuscript describes a flexible, pilot-scale setup that can be used for training students and carrying out research in process systems engineering. The setup allows one to study a variety of process systems engineering concepts such as design feasibility, design flexibility, control configuration selection, parameter estimation, process and…

  12. The Impact of Number Mismatch and Passives on the Real-Time Processing of Relative Clauses

    ERIC Educational Resources Information Center

    Contemori, Carla; Marinis, Theodoros

    2014-01-01

    Language processing plays a crucial role in language development, providing the ability to assign structural representations to input strings (e.g., Fodor, 1998). In this paper we aim at contributing to the study of children's processing routines, examining the operations underlying the auditory processing of relative clauses in children…

  13. A Flexible Pilot-Scale Setup for Real-Time Studies in Process Systems Engineering

    ERIC Educational Resources Information Center

    Panjapornpon, Chanin; Fletcher, Nathan; Soroush, Masoud

    2006-01-01

    This manuscript describes a flexible, pilot-scale setup that can be used for training students and carrying out research in process systems engineering. The setup allows one to study a variety of process systems engineering concepts such as design feasibility, design flexibility, control configuration selection, parameter estimation, process and…

  14. Fusion of product and process data: Batch-mode and real-time streaming

    SciTech Connect

    Vincent De Sapio; Spike Leonard

    1999-12-01

    In today's DP product realization enterprise it is imperative to reduce the design-to-fabrication cycle time and cost while improving the quality of DP parts (reducing defects). Much of this challenge resides in the inherent gap between the product and process worlds. The lack of seamless, bi-directional flow of information prevents true concurrency in the product realization world. This report addresses a framework for product-process data fusion to help achieve next generation product realization. A fundamental objective is to create an open environment for multichannel observation of process date, and subsequent mapping of that data onto product geometry. In addition to the sensor-based observation of manufacturing processes, model-based process data provides an important complement to empirically acquired data. Two basic groups of manufacturing models are process physics, and machine kinematics and dynamics. Process physics addresses analytical models that describe the physical phenomena of the process itself. Machine kinematic and dynamic models address the mechanical behavior of the processing equipment. As a secondary objective, an attempt has been made in this report to address part of the model-based realm through the development of an open object-oriented library and toolkit for machine kinematics and dynamics. Ultimately, it is desirable to integrate design definition, with all types of process data; both sensor-based and model-based. Collectively, the goal is to allow all disciplines within the product realization enterprise to have a centralized medium for the fusion of product and process data.

  15. A graphics processing unit accelerated motion correction algorithm and modular system for real-time fMRI.

    PubMed

    Scheinost, Dustin; Hampson, Michelle; Qiu, Maolin; Bhawnani, Jitendra; Constable, R Todd; Papademetris, Xenophon

    2013-07-01

    Real-time functional magnetic resonance imaging (rt-fMRI) has recently gained interest as a possible means to facilitate the learning of certain behaviors. However, rt-fMRI is limited by processing speed and available software, and continued development is needed for rt-fMRI to progress further and become feasible for clinical use. In this work, we present an open-source rt-fMRI system for biofeedback powered by a novel Graphics Processing Unit (GPU) accelerated motion correction strategy as part of the BioImage Suite project ( www.bioimagesuite.org ). Our system contributes to the development of rt-fMRI by presenting a motion correction algorithm that provides an estimate of motion with essentially no processing delay as well as a modular rt-fMRI system design. Using empirical data from rt-fMRI scans, we assessed the quality of motion correction in this new system. The present algorithm performed comparably to standard (non real-time) offline methods and outperformed other real-time methods based on zero order interpolation of motion parameters. The modular approach to the rt-fMRI system allows the system to be flexible to the experiment and feedback design, a valuable feature for many applications. We illustrate the flexibility of the system by describing several of our ongoing studies. Our hope is that continuing development of open-source rt-fMRI algorithms and software will make this new technology more accessible and adaptable, and will thereby accelerate its application in the clinical and cognitive neurosciences.

  16. A Graphics Processing Unit Accelerated Motion Correction Algorithm and Modular System for Real-time fMRI

    PubMed Central

    Scheinost, Dustin; Hampson, Michelle; Qiu, Maolin; Bhawnani, Jitendra; Constable, R. Todd; Papademetris, Xenophon

    2013-01-01

    Real-time functional magnetic resonance imaging (rt-fMRI) has recently gained interest as a possible means to facilitate the learning of certain behaviors. However, rt-fMRI is limited by processing speed and available software, and continued development is needed for rt-fMRI to progress further and become feasible for clinical use. In this work, we present an open-source rt-fMRI system for biofeedback powered by a novel Graphics Processing Unit (GPU) accelerated motion correction strategy as part of the BioImage Suite project (www.bioimagesuite.org). Our system contributes to the development of rt-fMRI by presenting a motion correction algorithm that provides an estimate of motion with essentially no processing delay as well as a modular rt-fMRI system design. Using empirical data from rt-fMRI scans, we assessed the quality of motion correction in this new system. The present algorithm performed comparably to standard (non real-time) offline methods and outperformed other real-time methods based on zero order interpolation of motion parameters. The modular approach to the rt-fMRI system allows the system to be flexible to the experiment and feedback design, a valuable feature for many applications. We illustrate the flexibility of the system by describing several of our ongoing studies. Our hope is that continuing development of open-source rt-fMRI algorithms and software will make this new technology more accessible and adaptable, and will thereby accelerate its application in the clinical and cognitive neurosciences. PMID:23319241

  17. Real-time water treatment process control with artificial neural networks

    SciTech Connect

    Zhang, Q.; Stanley, S.J.

    1999-02-01

    With more stringent requirements being placed on water treatment performance, operators need a reliable tool to optimize the process control in the treatment plant. In the present paper, one such tool is presented, which is a process control system built with the artificial neural network (ANN) modeling approach. The coagulation, flocculation, and sedimentation processes involve many complex physical and chemical phenomena and thus are difficult to model for process control with traditional methods. Proposed is the use of a neural network process control system for the coagulation, flocculation, and sedimentation processes. Presented is a review of influential control parameters and control requirements for these processes followed by the development of a feed forward neural network control scheme. A neural network process model was built based on nearly 2,000 sets of process control data. This model formed the major component of a software controller and was found to consistently predict the optimum alum and power activated carbon doses for different control actions. With minor modifications, the approach illustrated can be used for building control models for other water treatment processes.

  18. Real-time integrated process supervision for autotuners and modified cerebellar model articulation controller

    NASA Astrophysics Data System (ADS)

    Wahab, Abdul; Quek, H. C.; Lim, B. H.

    1998-10-01

    This paper presents the use of a micro-controller-based Integrated Process Supervision as a tool for investigate work in expert control. Two different control theories integrated within process serve as examples of structured approach to expert control. The Integrated Process Supervision is a refinement of the Expert Control Architecture as proposed by Karl J. Astrom by allowing integration of several control techniques in a single generic framework. Specifically, the paper presents the result for experiments performed on an implementation of the Integrated Process Supervision on a PC and micro-controller environment. Autotuning techniques were first integrated within the process supervision. Three Autotuners based on specification of phase and amplitude margins were investigated. A modified version of Cerebellar MOdel Articulation Controller was then implemented in IPS as a direct controller. Results collected verify its integration in the integrated process supervision and also provide evidence of improved performance as compared to Autotuning.

  19. Real-time scattered light dark-field microscopic imaging of the dynamic degradation process of sodium dimethyldithiocarbamate

    NASA Astrophysics Data System (ADS)

    Lei, Gang; Gao, Peng Fei; Liu, Hui; Huang, Cheng Zhi

    2015-12-01

    Single nanoparticle analysis (SNA) technique with the aid of a dark-field microscopic imaging (iDFM) technique has attracted wide attention owing to its high sensitivity. Considering that the degradation of pesticides can bring about serious problems in food and the environment, and that the real-time monitoring of the dynamic degradation process of pesticides can help understand and define their degradation mechanisms, herein we real-time monitored the decomposition dynamics of sodium dimethyldithiocarbamate (NaDDC) under neutral and alkaline conditions by imaging single silver nanoparticles (AgNPs) under a dark-field microscope (DFM); the localized surface plasmon resonance (LSPR) scattering signals were measured at a single nanoparticle level. As a result, the chemical mechanism of the degradation of NaDDC under neutral and alkaline conditions was proposed, and the inhibition effects of metal ions including Zn(ii) and Cu(ii) were investigated in order to understand the decomposition process in different environments. It was found that Cu(ii) forms the most stable complex with NaDDC with a stoichiometric ratio of 1 : 2, which greatly reduces the toxicity.Single nanoparticle analysis (SNA) technique with the aid of a dark-field microscopic imaging (iDFM) technique has attracted wide attention owing to its high sensitivity. Considering that the degradation of pesticides can bring about serious problems in food and the environment, and that the real-time monitoring of the dynamic degradation process of pesticides can help understand and define their degradation mechanisms, herein we real-time monitored the decomposition dynamics of sodium dimethyldithiocarbamate (NaDDC) under neutral and alkaline conditions by imaging single silver nanoparticles (AgNPs) under a dark-field microscope (DFM); the localized surface plasmon resonance (LSPR) scattering signals were measured at a single nanoparticle level. As a result, the chemical mechanism of the degradation of Na

  20. Selection of internal control genes for quantitative real-time RT-PCR studies during tomato development process

    PubMed Central

    Expósito-Rodríguez, Marino; Borges, Andrés A; Borges-Pérez, Andrés; Pérez, José A

    2008-01-01

    Background The elucidation of gene expression patterns leads to a better understanding of biological processes. Real-time quantitative RT-PCR has become the standard method for in-depth studies of gene expression. A biologically meaningful reporting of target mRNA quantities requires accurate and reliable normalization in order to identify real gene-specific variation. The purpose of normalization is to control several variables such as different amounts and quality of starting material, variable enzymatic efficiencies of retrotranscription from RNA to cDNA, or differences between tissues or cells in overall transcriptional activity. The validity of a housekeeping gene as endogenous control relies on the stability of its expression level across the sample panel being analysed. In the present report we describe the first systematic evaluation of potential internal controls during tomato development process to identify which are the most reliable for transcript quantification by real-time RT-PCR. Results In this study, we assess the expression stability of 7 traditional and 4 novel housekeeping genes in a set of 27 samples representing different tissues and organs of tomato plants at different developmental stages. First, we designed, tested and optimized amplification primers for real-time RT-PCR. Then, expression data from each candidate gene were evaluated with three complementary approaches based on different statistical procedures. Our analysis suggests that SGN-U314153 (CAC), SGN-U321250 (TIP41), SGN-U346908 ("Expressed") and SGN-U316474 (SAND) genes provide superior transcript normalization in tomato development studies. We recommend different combinations of these exceptionally stable housekeeping genes for suited normalization of different developmental series, including the complete tomato development process. Conclusion This work constitutes the first effort for the selection of optimal endogenous controls for quantitative real-time RT-PCR studies of gene