Real-time Module Research Articles

An Online System for Nowcasting Satellite Derived Temperatures for Urban Areas

The Urban Heat Island (UHI) is an adverse environmental effect of urbanization that increases the energy demand of cities and impacts human health. The study of this effect for monitoring and mitigation purposes is crucial, but it is hampered by the lack of high spatiotemporal temperature data. This article presents the work undertaken for the implementation of an operational real-time module for monitoring 2 m air temperature (TA) at a spatial resolution of 1 km based on the Meteosat Second Generation—Spinning Enhanced Visible and Infrared Imager (MSG-SEVIRI). This new module has been developed in the context of an operational system for monitoring the urban thermal environment. The initial evaluation of TA products against meteorological in situ data from 15 cities in Europe and North Africa yields that its accuracy in terms of Root Mean Square Error (RMSE) is 2.3 °C and Pearson’s correlation coefficient (Rho) is 0.95. The temperature information made available at and around cities can facilitate the assessment of the UHIs in real time but also the timely generation of relevant higher value products and services for energy demand and human health studies. The service is available at http://snf-652558.vm.okeanos.grnet.gr/treasure/portal/info.html.

Hardware-in-the-loop control of additive manufacturing processes using temperature feedback

Laser-based additive manufacturing is a technology for the production of freeform metallic parts. In order to produce parts with high quality, it is important for the manufacturing processes to be controllable with a high degree of precision. Current additive manufacturing systems attempt to reach this goal by carefully tuning the operational parameters, often in combination with a feedback control system. These systems are based on low order, empirical models of the process, which may limit the performance that can be achieved. This paper introduces a control system based on a high order physical heat conduction model of the melt pool dynamics. The control system serves as a framework which can be applied to many laser material processes in which high precision is required such as laser cladding and selective laser melting. The controller is able to regulate the melt pool size by modulating the laser power using a number of surface temperature measurements as the feedback signal. A hardware-in-the-loop (HIL) system was built to enable safe and cost-effective testing of the controller hardware in different simulation environments. The HIL setup includes a real-time image processing module for extracting the required temperature information from hyperspectral data generated by detailed numerical simulations of the melt pool dynamics. Hyperspectral measurements are performed on a laser cladding system to validate the simulation results.

Integrated system for site-specific earthquake hazard assessment with geotechnical spatial grid information based on GIS

An integrated earthquake hazard assessment system with geotechnical spatial grid information was developed based on a geographic information system (GIS). The developed system, built, within the frame of GIS, consists of a database (DB) containing all available site information and processed data in the standard formats, and system software that performs various functions to manage and utilize the data in the DB. The system software is divided functionally into an input module, a geostatistical three-dimensional integration module, a real-time earthquake hazard assessment module, and an output or visualization module. A systematic framework for construction of a geotechnical spatial grid was developed to consider local site response characteristics for target areas. According to the framework, three interrelated assessment procedures were incorporated into the DB on a real-time basis: real-time seismic load determination, real-time liquefaction hazard estimation, and real-time structure fragility evaluation. The DB and these sub-modules of the system software were combined and integrated into a single system to provide a familiar and user-friendly working environment with a standard interface. In addition, the integrated system was imbedded into the Korea Integrated Seismic System server to be linked with real-time seismic accelerations, and a simulation of the system was specifically conducted at Incheon Port, Korea, using two actual earthquake events (the 2013 Baengnyeong and 2014 Taean earthquakes) and one virtual earthquake scenario. The simulation results were visualized as a geotechnical earthquake hazard map to verify the computer-aided real-time assessment framework at the times, when the three notable earthquake events occurred at the nearby Incheon Port.

Wine Traceability: A Data Model and Prototype in Albanian Context.

Vine traceability is a critical issue that has gained interest internationally. Quality control programs and schemes are mandatory in many countries including EU members and the USA. Albania has transformed most of the EU regulations on food into laws. Regarding the vine sector, the obligation of wine producers to keep traceability data is part of the legislation. The analysis on the interviews conducted with Albanian winemakers show that these data are actually recorded only in hard copy. Another fact that emerges from the interviews is that only two producers have implemented the ISO (International Organization for Standardization) standards on food. The purpose of this paper is to develop an agile and automated traceability system based on these standards. We propose a data model and system prototype that are described in the second and third section of this work. The data model is an adaption along the lines of the GS1 (Global Standards One) specifications for a wine supply chain. The proposed prototype has a key component that is mobile access to the information about wine through barcode technology. By using this mechanism the consumer obtains transparency on his expectations concerning the quality criteria. Another important component of the proposed system in this paper is a real-time notification module that works as an alert system when a risk is identified. This can help producers and authorities to have a rapid identification of a contaminated product. It is important in cases when recalling the product from the market or preventing it from reaching the consumer.

Autonomous wheelchair navigation with real time obstacle detection using 3D sensor

Autonomous wheelchairs operating in dynamic environments need to sense its surrounding environment and adapt the control signal, in real-time, to avoid collisions and protect the user. In this paper we propose a robust, simple and real-time autonomous navigation module that drives a wheelchair toward a desired target, along with its capability to avoid obstacles in a 3D dynamic environment. To command the mobile robot to the target, we use a Fuzzy Logic Controller (FLC). For obstacle avoidance, we use the Kinect Xbox 360 to provide an actual map of the environment. The generated map is fed to the reactive obstacle avoidance control Deformable Virtual Zone (DVZ). Simulations and real world experiments results are reported to show the feasibility and the performance of the proposed control system.

Hardware Design of Moving Object Detection on Reconfigurable System

Moving object detection including background subtraction and morphological processing is a critical research topic for video surveillance because of its high computational loading and power consumption. This paper proposes a hardware design to accelerate the computation of background subtraction with low power consumption. A real-time background subtraction method is designed with a frame-buffer scheme and function partition to improve throughput, and implemented using Verilog HDL on FPGA. The design parallelizes the computations of background update and subtraction with a seven-stage pipeline. A stripe-based morphological processing and accounting for the completion of detected objects is devised. Simulation results for videos of VGA resolutions on a low-end FPGA device show 368 fps throughput for only the real-time background subtraction module, and 51 fps for the whole system, including off-chip memory access. Real-time efficiency with low power consumption and low resource utilization is thus demonstrated.

NUI framework based on real-time head pose estimation and hand gesture recognition

The natural user interface (NUI) is used for the natural motion interface without using device or tool such as mice, keyboards, pens and markers. In this paper, we develop natural user interface framework based on two recognition module. First module is real-time head pose estimation module using random forests and second module is hand gesture recognition module, named Hand gesture Key Emulation Toolkit (HandGKET). Using the head pose estimation module, we can know where the user is looking and what the user’s focus of attention is. Moreover, using the hand gesture recognition module, we can also control the computer using the user’s hand gesture without mouse and keyboard. In proposed framework, the user’s head direction and hand gesture are mapped into mouse and keyboard event, respectively.

A new Self-Adaptive disPatching System for local clusters

The scheduler is one of the most important components of a high performance cluster. This paper introduces a self-adaptive dispatching system (SAPS) based on Torque[1] and Maui[2]. It promotes cluster resource utilization and improves the overall speed of tasks. It provides some extra functions for administrators and users. First of all, in order to allow the scheduling of GPUs, a GPU scheduling module based on Torque and Maui has been developed. Second, SAPS analyses the relationship between the number of queueing jobs and the idle job slots, and then tunes the priority of users’ jobs dynamically. This means more jobs run and fewer job slots are idle. Third, integrating with the monitoring function, SAPS excludes nodes in error states as detected by the monitor, and returns them to the cluster after the nodes have recovered. In addition, SAPS provides a series of function modules including a batch monitoring management module, a comprehensive scheduling accounting module and a real-time alarm module. The aim of SAPS is to enhance the reliability and stability of Torque and Maui. Currently, SAPS has been running stably on a local cluster at IHEP (Institute of High Energy Physics, Chinese Academy of Sciences), with more than 12,000 cpu cores and 50,000 jobs running each day. Monitoring has shown that resource utilization has been improved by more than 26%, and the management work for both administrator and users has been reduced greatly.

Design and real time implementation of type-2 fuzzy vector control for DFIG based wind generators

Doubly fed induction generator is very sensitive to voltage variations in the grid, which pose limitation for wind power plants during the grid integrated operation. Handling the uncertainity in wind speed and grid faults is a major challenge to fulfill the modern grid code requirements. This paper proposes a new control strategy for Rotor side converter using Interval type-2 fuzzy sets which can model and handle uncertainties in the system parameters. The presence of third dimension in the membership function, offers an additional degree of freedom in the design of the controller to counter the effects of fluctuations in wind speed and low voltage during severe grid fault conditions. A 2 MW DFIG connected to the grid is modelled in simulation software RSCAD and interfaced with Real time digital simulator (RTDS) to perform the simulations in real-time. The RTDS platform is considered by many research laboratories as real-time testing module for controller prototyping and also for hardware in the loop (HIL) applications. The controller performance is evaluated in HIL configuration, by performing the real-time simulations under various parameter uncertainties. The proposed controller can improve the low voltage ride through capability of DFIG compared to that of PI and type-1 fuzzy controller.

Use of Real-Time Programming Modules for Control of Actuator Positioning in Mechatronic System with Pneumatic Artificial Muscles

This paper explains proposed real-time control system algorithm modifications for control of drives containing the artificial muscles. The aim of these modifications is to create control algorithm more effective in spite to provide effective computational time to prepare measurement chain to add further artificial muscles to ensure movement in another directions. Described are devices, hardware and software equipment, as well as design of their involvement in the experimental device.

Instrumenting complex exoskeletons for improved human-robot interaction

Gone is the era where robots were strictly used for industrial automation, working in a single, isolated welding cell from an assembly line, away from their human overlords and relegated to repetitive brainless preprogrammed tasks. Modern robotics in contrast, is rapidly evolving in a more inclusive way for the robots, bringing them closer to us humans, and opening in the process a huge and diverse spectrum of applications. We have developed a generic, low level control (LLC) real-time system for the sensor data acquisition and control of complex robots together with the development of versatile electronic hardware modules. In this article, we explain existing exoskeletons, propose generic solutions to challenges considered for safe physical human-robot interaction, and describe the instrumentation and integration of our real-time system and electronic hardware modules that we developed and successfully deployed in three exoskeleton systems.

State‐of‐charge optimising control approach of battery energy storage system for wind farm

In recent years, configuring battery energy storage system (BESS) in wind farm has become the most popular method to smooth wind power fluctuation. The effectiveness of wind power fluctuation smoothing relies on the charging/discharging power control and state of charge (SOC) regulation of BESS. This study proposed a novel optimising SOC control approach for BESS in wind farm which could regulate wind power fluctuation in a suitable level and maintain SOC in an optimal range by utilising the wind power prediction information. A wind power prediction-based optimal SOC calculation module is designed to obtain an optimal range of SOC which makes BESS have enough capacity to smooth wind power fluctuation in a finite future period of time. It takes minimising over-charging and over-discharging time as optimisation objectives and biggest variations of wind farm outputting power within 1 and 10 min as restraint. A fuzzy self-adjusting of filter-based real-time control module is designed to smooth the wind power fluctuation in real time and regulate SOC to the optimal range. Finally, the effectiveness of the proposed approach was demonstrated through implementing it in wind power smoothing control simulation experiments.

Design of trigonometric velocity scheduling algorithm based on pre-interpolation and look-ahead interpolation

To generate continuous velocity, acceleration and jerk curves of parametric interpolation in high-speed and high-accuracy machining, this paper presents a trigonometric velocity scheduling algorithm based on two-time look-ahead interpolation (pre-interpolation and look-ahead interpolation). The algorithm consists of three modules: pre-interpolation, look-ahead interpolation and real-time interpolation. The pre-interpolation module aims to explore and record the information of the path to be machined. The look-ahead interpolation module firstly calculates the velocity scheduling functions according to the data recorded by pre-interpolation, and then tests and adjusts the feedrate scheduling schemes constantly. The real-time interpolation module adapts the method of beforehand deceleration or delaying acceleration according to the signals received from pre-interpolation and look-ahead interpolation to guarantee the processing accuracy. Simulation and experimental tests demonstrate the availability, effectiveness and advantages of the trigonometric velocity scheduling algorithm. And the proposed trigonometric velocity scheduling algorithm based on pre-interpolation and look-ahead interpolation could realize smooth velocity, acceleration and jerk control with restricted chord error and implement high-quality CNC processing.

High-Speed Data Processing Module for LLRF

Linear accelerators, like the Free-electron LASer in Hamburg (FLASH) or the European X-Ray Free Electron Laser (E-XFEL) take advantage of the digital Low Level Radio Frequency (LLRF) system to control the phase and amplitude of an electromagnetic field inside superconducting cavities. The real-time control LLRF system, processing data within a few microseconds, has to fulfil performance requirements and provide comprehensive monitoring and diagnostics. The AMC-based controller (DAMC-TCK7) board was developed as a general purpose high-performance low-latency data processing unit designed according to the PICMG MTCA.4 spec. The module provides the processing power, data memory, communication links, reference clock, trigger and interlock signals that are required in modern LLRF control systems. The module was originally designed as a cavity field stabilizing controller for standing-wave linear accelerators. However, the application of the board is much wider because it is a general purpose data processing module suitable for systems requiring low latency and high-speed digital signal processing. According to authors' knowledge this is the first MTCA.4 module offering 12.5 Gbps links, unified Zone 3 connectivity and advanced Module Management Controller proposed by DESY. The DAMC-TCK7 card was used as a hardware template for the development of the other AMC modules of the XFEL accelerator's LLRF system. This paper discusses the requirements for the digital real-time data processing module, presents the laboratory performance evaluation and verification in Cryo-Module Test Bench (CMTB) at DESY.

English

This paper is about the application of data acquisition systems in industrial requirements for real time execution of events with industrial process control and automation. The main core of the system is an embedded hardware running a scaled-down version of Linux: a popular choice of operating system for embedded applications. On -line embedded web server is a challenging part of many embedded and real time data acquisition and control system applications. The World Wide Web is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billion of users worldwide and allows the user to interface many real time embedded applications like data acquisition, Industrial automations and safety measures etc., In this project we approached towards the design and development of on-line Interactive Data Acquisition and Control System (IDACS) using ARM based embedded web server. It can be a network, intelligent and digital distributed control system. Single chip IDACS method improves the processing capability of a system and overcomes the problem of poor real time and reliability. This system uses ARM9 Processor portability with Linux operating system it makes the system which handling various processes based on multi tasking and reliable scheduling mechanisms. A novel approach is introduced to minimize the operational costs while operating with a large amount of data. The system is demonstrated to be suitable for different embedded applications by attaching several real-time modules through appropriate interfaces. The embedded web server technology is the combination of embedded device and Internet technology, through this embedded web server user can access their equipments remotely. The equipment mentioned here could be home appliances and factory devices. This paper is focused on realization of TCP/IP suite and user development platform for this embedded web server. The embedded web server design includes a complete web server with TCP/IP support and Ethernet interface. Web pages are written by Hyper text markup language (HTML).

Software-based high-level synthesis design of FPGA beamformers for synthetic aperture imaging.

Field-programmable gate arrays (FPGAs) can potentially be configured as beamforming platforms for ultrasound imaging, but a long design time and skilled expertise in hardware programming are typically required. In this article, we present a novel approach to the efficient design of FPGA beamformers for synthetic aperture (SA) imaging via the use of software-based high-level synthesis techniques. Software kernels (coded in OpenCL) were first developed to stage-wise handle SA beamforming operations, and their corresponding FPGA logic circuitry was emulated through a high-level synthesis framework. After design space analysis, the fine-tuned OpenCL kernels were compiled into register transfer level descriptions to configure an FPGA as a beamformer module. The processing performance of this beamformer was assessed through a series of offline emulation experiments that sought to derive beamformed images from SA channel-domain raw data (40-MHz sampling rate, 12 bit resolution). With 128 channels, our FPGA-based SA beamformer can achieve 41 frames per second (fps) processing throughput (3.44 × 10(8) pixels per second for frame size of 256 × 256 pixels) at 31.5 W power consumption (1.30 fps/W power efficiency). It utilized 86.9% of the FPGA fabric and operated at a 196.5 MHz clock frequency (after optimization). Based on these findings, we anticipate that FPGA and high-level synthesis can together foster rapid prototyping of real-time ultrasound processor modules at low power consumption budgets.

A web-based collaborative framework for facilitating decision making on a 3D design developing process

Abstract Increased competitive challenges are forcing companies to find better ways to bring their applications to market faster. Distributed development environments can help companies improve their time-to-market by enabling parallel activities. Although, such environments still have their limitations in real-time communication and real-time collaboration during the product development process. This paper describes a web-based collaborative framework which has been developed to support the decision making on a 3D design developing process. The paper describes 3D design file for the discussion that contains all relevant annotations on its surface and their visualization on the user interface for design changing. The framework includes a native CAD data converting module, 3D data based real-time communication module, revision control module for 3D data and some sub-modules such as data storage and data management. We also discuss some raised issues in the project and the steps underway to address them.

A lab-on-a-chip system integrating tissue sample preparation and multiplex RT-qPCR for gene expression analysis in point-of-care hepatotoxicity assessment.

A truly practical lab-on-a-chip (LOC) system for point-of-care testing (POCT) hepatotoxicity assessment necessitates the embodiment of full-automation, ease-of-use and "sample-in-answer-out" diagnostic capabilities. To date, the reported microfluidic devices for POCT hepatotoxicity assessment remain rudimentary as they largely embody only semi-quantitative or single sample/gene detection capabilities. In this paper, we describe, for the first time, an integrated LOC system that is somewhat close to a practical POCT hepatotoxicity assessment device - it embodies both tissue sample preparation and multiplex real-time RT-PCR. It features semi-automation, is relatively easy to use, and has "sample-in-answer-out" capabilities for multiplex gene expression analysis. Our tissue sample preparation module incorporating both a microhomogenizer and surface-treated paramagnetic microbeads yielded high purity mRNA extracts, considerably better than manual means of extraction. A primer preloading surface treatment procedure and the single-loading inlet on our multiplex real-time RT-PCR module simplify off-chip handling procedures for ease-of-use. To demonstrate the efficacy of our LOC system for POCT hepatotoxicity assessment, we perform a preclinical animal study with the administration of cyclophosphamide, followed by gene expression analysis of two critical protein biomarkers for liver function tests, aspartate transaminase (AST) and alanine transaminase (ALT). Our experimental results depict normalized fold changes of 1.62 and 1.31 for AST and ALT, respectively, illustrating up-regulations in their expression levels and hence validating their selection as critical genes of interest. In short, we illustrate the feasibility of multiplex gene expression analysis in an integrated LOC system as a viable POCT means for hepatotoxicity assessment.

A Wind Power and Load Prediction Based Frequency Control Approach for Wind-Diesel-Battery Hybrid Power System

A frequency control approach based on wind power and load power prediction information is proposed for wind-diesel-battery hybrid power system (WDBHPS). To maintain the frequency stability by wind power and diesel generation as much as possible, a fuzzy control theory based wind and diesel power control module is designed according to wind power and load prediction information. To compensate frequency fluctuation in real time and enhance system disturbance rejection ability, a battery energy storage system real-time control module is designed based on ADRC (active disturbance rejection control). The simulation experiment results demonstrate that the proposed approach has a better disturbance rejection ability and frequency control performance compared with the traditional droop control approach.

LoMA-B: a simple and versatile lab-on-a-chip system based on single-channel bisulfite conversion for DNA methylation analysis.

Miniaturized lab-on-a-chip (LOC) systems have been developed for genetic and epigenetic analyses in clinical applications because of advantages such as reduced sample size and reagent consumption, rapid processing speed, simplicity, and enhanced sensitivity. Despite tremendous efforts made towards developing LOC systems for use in the clinical setting, the development of LOC systems to analyze DNA methylation, which is an emerging epigenetic marker causing the abnormal silencing of genes including tumor suppressor genes, is still challenging because of the gold standard methods involving a bisulfite conversion step. Existing bisulfite conversion-based techniques are not suitable for clinical use due to their long processing time, labor intensiveness, and the purification steps involved. Here, we present a lab-on-a-chip system for DNA methylation analysis based on bisulfite conversion (LoMA-B), which couples a sample pre-processing module for on-chip bisulfite conversion and a label-free, real-time detection module for rapid analysis of DNA methylation status using an isothermal DNA amplification/detection technique. The methylation status of the RARβ gene in human genomic DNA extracted from MCF-7 cells was analyzed by the LoMA-B system within 80 min (except 16 h for sensor preparation) compared to conventional MS-PCR within 24 h. Furthermore, the LoMA-B system is highly sensitive and can detect as little as 1% methylated DNA in a methylated/unmethylated cell mixture. Therefore, the LoMA-B system is an efficient diagnostic tool for the simple, versatile, and quantitative evaluation of DNA methylation patterns for clinical applications.