Uncertainty propagation: Avoiding the expensive sampling process for real-time image-based measurements

Leveraging virtualization technology, Mobile Edge Computing (MEC) deploys multiple services with different execution time requirements running as isolated processes. For instance, both real-time (RT) and non-RT applications may be (are) running on the same infrastructure using containerized virtualization. Nevertheless, sharing resources (e.g., CPU) with collocated workloads could impact the RT performance of RT applications. This paper presents PRINCIPIA, a dynamic CPU and CPU-shares allocation mechanism that opportunistically enables non-RT applications to run on underutilized CPUs while providing RT guarantees to RT applications. By monitoring MEC’s system metrics like processor’s CPU utilization and container’s CPU usage, PRINCIPIA dynamically allocates both CPU and CPU-shares to containers running non-RT applications aiming at opportunistically exploiting underutilized CPUs by containers running RT applications. We evaluate PRINCIPIA on a small-scale MEC server which uses containerized virtualization along with Linux RT Kernel to deploy both RT and non-RT applications. Our findings show that PRINCIPIA mitigates the impact on the RT performance of RT applications providing bounded processing latency in comparison with the default host Kernel scheduler.

When designing a system capable of capturing and displaying three-dimensional (3-D) moving images in real time by the integral imaging (II) method, one challenge is to eliminate pseudoscopic images. To overcome this problem, we propose a simple system with an array of three convex lenses. This paper first describes by geometrical optics the lateral magnification of the elemental optics and expansion of an elemental image, confirming that the elemental optics satisfies the conditions under which pseudoscopic images can be avoided. By the II method, adjacent elemental images must not overlap, a condition also satisfied by the proposed optical system. Next, the paper describes an experiment carried out to acquire and display 3-D images. The real-time system we have constructed comprises elemental optics array with 54(H) x 59(V) elements, a CCD camera to capture a group of elemental images created by the lens array, and a liquid crystal panel to display these images. The experiment results confirm that the system produces orthoscopic images in real time and so is effective for real-time application of the II method.

Collision Probability with Gaussian Mixture Orbit Uncertainty

Image compression is a basic need for the progressive transmission or storage of image data via any media. For the effective processing of image data the coding standards were developed. The most commonly used standard in current scenario is the JPEG and JPEG-2000 coding. These standards have become the industry standards and are progressively been in use for almost all image processing applications. In the process of image coding various sub-processing operations occur which process the image blocks by transformation, quantization and encoding before transmitting or storing. In the process, quantization is observed to be a time consuming and is needed to be processed in high precision so as to achieve less processing error and also in reasonable time. The process of quantization has shown greater efficiency in vector quantization than earlier methods. Vector quantization is observed to be an efficient block based lossy compression technique. Due to simpler coding process and high compression ratio VQ are widely used. Predictive vector Quantization (PVQ) is commonly used memory based vector Quantization method. The main drawback with PVQ is the high computational complexity which limits PVQ to use in real time applications. Shorter coding time can be archived by reducing the number of code words or instructions, but the reconstructed image quality will degraded in the case of fewer code words. Hence, it is necessary to propose fast coding algorithms for PVQ. In this paper a modified version of the PVQ approach has been suggested in order to process faster, which ensue to be a compatible mechanism for real time image coding in JPEG based coding system. Keywords: Compression, quantization, PVQ encoder, mean-square-error, Discrete Cosine Transform.

We are studying electronic holography and have developed a real-time color holography system for live scene which includes three functional blocks, capture block, processing block, and display block. In this paper, we will introduce our developed system after describing basic idea that quickly calculates hologram from IP image. The first block, capture block, uses integral photography (IP) technology to capture color 3-D objects under natural light in real time. The second block, processing block, consists of four general personal computers to generate holograms from IP images in real time. Three half-zone-plated holograms for red, green and blue (RGB) channels are generated for all captured IP images by using fast Fourier Transform. The last block, display block, mainly consists of three liquid crystal displays to display the holograms and three laser sources for RGB to reconstruct the color 3-D objects. All blocks work in real time, i.e., in 30 color frames per second.

Laser Speckle Contrast Imaging (LSCI) has emerged as a promising imaging modality that offers full field, real time, continuous and agent free monitoring of cerebral blood flow during neurosurgery. Since LSCI does not require the injection of a contrast agent, it has the potential to complement fluorescence-based modalities by providing continuous and dynamic changes in blood flow during critical moments of neurosurgery. We performed a clinical study with LSCI to investigate the clinical utility of the technique intraoperatively. A commercially available Zeiss Pentero 900® microscope was equipped with a λ=785nm laser diode attached to a customized mount. The backscattered laser light was collected by the microscope, producing a laser speckle image on the external camera which was mounted on the microscope side-port. Custom software collected laser speckle images, computed, and then displayed the speckle contrast images in real time throughout the surgery onto the operating room monitors. The images were displayed with custom color maps and thresholding. The robust integration in the surgical workflow of the technology enabled the investigation of the need for dynamic vessel-flow characterization in 20-patients at the Inselspital in Bern, Switzerland. We assessed vessel flow during key time points in the surgery and provided real time and continuous measurements to the surgeon.

Ultrasound image fusion for external beam radiotherapy for prostate cancer

The paper presents a novel approach for uncertainty propagation in multicomponent two-phase displacements. This approach originates from and extends the frozen streamlines (FROST) distribution method for two-phase Buckley–Leverett displacements described in Ibrahima et al. (Transp Porous Media 109(1):81–107, 2015). The developed FROST method for multicomponent systems relies on the analytical solutions of gas–oil displacements provided by the theory of gas injection processes. With examples considering a stochastic porosity field in 1-D, we apply the developed framework to uncertainty propagation in three- and four-component systems to obtain the probability distribution of different compositions in space and time and verify that the results are in excellent agreement with the reference analytical Monte Carlo simulations.

Characterization and real-time measurement of geometrical appearance of the weld pool

In JET with ITER-like wall (JET-ILW), the first wall was changed to metallic materials (tungsten and beryllium) [] which require a reliable protection system to avoid damage of the plasma-facing components (PFCs) due to beryllium melting or cracking of tungsten owing to thermal fatigue. To address this issue, a protection system with real time control, based on imaging diagnostics, has been implemented on JET-ILW in 2011.This paper describes the design, implementation, and operation of the near infrared imaging diagnostic system of the JET-ILW plasma experiment and its integration into the existing JET-ILW protection architecture. The imaging system comprises eleven analogue CCD cameras which demonstrate a high robustness against changes of system parameters like the emissivity. The system covers about two thirds of the main chamber wall and almost half of the divertor. A real-time imaging processing unit is used to convert the raw data into surface temperatures taking into account the different emissivity for the various materials and correcting for artefacts resulting e.g. from neutron impact. Regions of interest (ROI) on the selected PFCs are analysed in real time and the maximum temperature measured for each ROI is sent to other real time systems to trigger an appropriate response of the plasma control system, depending on the location of a hot spot.A hot spot validation algorithm was successfully integrated into the real-time system and is now used to avoid false alarms caused by neutrons and dust. The design choices made for the video imaging system, the implications for the hardware components and the calibration procedure are discussed. It will be demonstrated that the video imaging protection system can work properly under harsh electromagnetic conditions as well as under neutron and gamma radiation. Examples will be shown of instances of hot spot detection that abort the plasma discharge. The limits of the protection system and the associated constraints on plasma operation are also presented.The real-time protection system has been operating routinely since 2011. During this period, less than 0.5% of the terminated discharges were aborted by a malfunction of the system. About 2%–3% of the discharges were terminated due to the detection of actual hot spots.

We present a new variable-step Gauss–Legendre implicit-Runge–Kutta-based approach for orbit and uncertainty propagation, VGL-IRK, which includes adaptive step-size error control and which collectively, rather than individually, propagates nearby sigma points or states. The performance of VGL-IRK is compared to a professional (variable-step) implementation of Dormand–Prince 8(7) (DP8) and to a fixed-step, optimally-tuned, implementation of modified Chebyshev–Picard iteration (MCPI). Both nearly-circular and highly-elliptic orbits are considered using high-fidelity gravity models and realistic integration tolerances. VGL-IRK is shown to be up to eleven times faster than DP8 and up to 45 times faster than MCPI (for the same accuracy), in a serial computing environment. Parallelization of VGL-IRK and MCPI is also discussed.

We present a statistical framework for model calibration and uncertainty estimation for complex deterministic models. A Bayesian approach is used to combine data from observations, the deterministic model, and prior parameter distributions to obtain forecast distributions. A case study is presented in which the statistical framework is applied using the hydrogeochemical model (MAGIC) for an assessment of recovery from acidification of soils and surface waters at a long-term study site in Norway under different future acid deposition conditions. The water quality parameters are coupled with a simple dose-response model for trout population health. Uncertainties in model output parameters are estimated and forecast results are presented as probability distributions for future water chemistry and as probability distributions of future healthy trout populations. The forecast results are examined for three different scenarios of future acid deposition corresponding to three different emissions control strategies for Europe. Despite the explicit consideration of uncertainties propagated into the future forecasts, there are clear differences among the scenarios. The case study illustrates how inclusion of uncertainties in model predictions can strengthen the inferences drawn from model results in support of decision making and assessments.

The objectives of this study were to develop a real-time tillage depth measurement system for agricultural tractor performance analysis and then to validate these configured systems through soil non-penetration tests and field experiment during plow tillage. The real-time tillage depth measurement system was developed by using a sensor fusion method, consisting of a linear potentiometer, inclinometer, and optical distance sensor to measure the vertical penetration depth of the attached implement. In addition, a draft force measurement system was developed using six-component load cells, and an accuracy of 98.9% was verified through a static load test. As a result of the soil non-penetration tests, it was confirmed that sensor fusion type A, consisting of a linear potentiometer and inclinometer, was 6.34–11.76% more accurate than sensor fusion type B, consisting of an optical distance sensor and inclinometer. Therefore, sensor fusion type A was used during field testing as it was found to be more suitable for use in severe working environments. To verify the accuracy of the real-time tillage depth measurement system, a linear regression analysis was performed between the measured draft and the predicted values calculated using the American Society of Agricultural and Biological Engineers (ASABE) standards-based equation. Experimental data such as traveling speed and draft force showed that it was significantly affected by tillage depth, and the coefficient of determination value at M3–Low was 0.847, which is relatively higher than M3–High. In addition, the regression analysis of the integrated data showed an R-square value of 0.715, which is an improvement compared to the accuracy of the ASABE standard prediction formula. In conclusion, the effect of tillage depth on draft force of agricultural tractors during plow tillage was analyzed by the simultaneous operation of the proposed real-time tillage depth measurement system and draft force measurement system. In addition, system accuracy is higher than the predicted accuracy of 40% based on the ASABE standard equation, which is considered to be useful for various agricultural machinery research fields. In future studies, real-time tillage depth measurement systems can be used in tractor power train design and to ensure component reliability, in accordance with agricultural working conditions, by predicting draft force and axle loads depending on the tillage depth during tillage operations.

For measurement of minute change in thickness using ultrasound, the phase tracking method based on the constraint least-squares approach has been developed. By using the thickness change of arterial wall measured by this method, local elastic characteristic of the arterial wall is calculated, and fast calculation makes a real-time 2D measurement of the elastic characteristics possible. We have developed a real-time measurement system that displays the 2D image of the elastic characteristics of the arterial wall. In order to assess the measurement accuracy of the system, we made a phantom of silicone tube, and the thickness change of the tube wall was measured by the system and another off-line ultrasound measurement system. From the experimental results, it was obtained that our novel system had an accuracy of about 0.2 /spl mu/m. using this system, we measured the thickness change of carotid arterial wall, and obtained real-time 2D images of the elastic characteristics.

Visualization is very useful for the study of the heart, but it is still a challenging work to display the detailed heart because of the complex structure and expensive computation. Very few systems have been developed to satisfy this work specially. In this paper, we designed and implemented a GPU-based and real-time cardiac visualization system (GRCVS). The illumination model and the context-preserving model are integrated into the system, so that it can generate better images and preserve the important boundary information at the same time. The rendering process is programmed with CUDA, which helps to view the final image in real time. The system also provides strong interactive ability: it supplies visual and concise interfaces to set various parameters which are used to adjust image effect and user can also use simple ways to observe the images quickly and conveniently. The system has been proved to be valuable for the study of the heart in biomedical field.