scholarly journals Extended Joint Sparsity Reconstruction for Spatial and Temporal ERT Imaging

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 4014 ◽  
Author(s):  
Bo Chen ◽  
Juan Abascal ◽  
Manuchehr Soleimani

Electrical resistance tomography (ERT) is an imaging technique to recover the conductivity distribution with boundary measurements via attached electrodes. There are a wide range of applications using ERT for image reconstruction or parameter calculation due to high speed data collection, low cost, and the advantages of being non-invasive and portable. Although ERT is considered a high temporal resolution method, a temporally regularized method can greatly enhance such a temporal resolution compared to frame-by-frame reconstruction. In some of the cases, especially in the industrial applications, dynamic movement of an object is critical. In practice, it is desirable for monitoring and controlling the dynamic process. ERT can determine the spatial conductivity distribution based on previous work, and ERT potentially shows good performance in exploiting temporal information as well. Many ERT algorithms reconstruct images frame by frame, which is not optimal and would assume that the target is static during collection of each data frame, which is inconsistent with the real case. Although spatiotemporal-based algorithms can account for the temporal effect of dynamic movement and can generate better results, there is not that much work aimed at analyzing the performance in the time domain. In this paper, we discuss the performance of a novel spatiotemporal total variation (STTV) algorithm in both the spatial and temporal domain, and Temporal One-Step Tikhonov-based algorithms were also employed for comparison. The experimental results show that the STTV has a faster response time for temporal variation of the moving object. This robust time response can contribute to a much better control process which is the main aim of the new generation of process tomography systems.

2021 ◽  
Vol 11 (10) ◽  
pp. 4610
Author(s):  
Simone Berneschi ◽  
Giancarlo C. Righini ◽  
Stefano Pelli

Glasses, in their different forms and compositions, have special properties that are not found in other materials. The combination of transparency and hardness at room temperature, combined with a suitable mechanical strength and excellent chemical durability, makes this material indispensable for many applications in different technological fields (as, for instance, the optical fibres which constitute the physical carrier for high-speed communication networks as well as the transducer for a wide range of high-performance sensors). For its part, ion-exchange from molten salts is a well-established, low-cost technology capable of modifying the chemical-physical properties of glass. The synergy between ion-exchange and glass has always been a happy marriage, from its ancient historical background for the realisation of wonderful artefacts, to the discovery of novel and fascinating solutions for modern technology (e.g., integrated optics). Getting inspiration from some hot topics related to the application context of this technique, the goal of this critical review is to show how ion-exchange in glass, far from being an obsolete process, can still have an important impact in everyday life, both at a merely commercial level as well as at that of frontier research.


Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3655 ◽  
Author(s):  
Camilo J. Bastidas Pacheco ◽  
Jeffery S. Horsburgh ◽  
Robb J. Tracy

We present a low-cost (≈$150) monitoring system for collecting high temporal resolution residential water use data without disrupting the operation of commonly available water meters. This system was designed for installation on top of analog, magnetically driven, positive displacement, residential water meters and can collect data at a variable time resolution interval. The system couples an Arduino Pro microcontroller board, a datalogging shield customized for this specific application, and a magnetometer sensor. The system was developed and calibrated at the Utah Water Research Laboratory and was deployed for testing on five single family residences in Logan and Providence, Utah, for a period of over 1 month. Battery life for the device was estimated to be over 5 weeks with continuous data collection at a 4 s time interval. Data collected using this system, under ideal installation conditions, was within 2% of the volume recorded by the register of the meter on which they were installed. Results from field deployments are presented to demonstrate the accuracy, functionality, and applicability of the system. Results indicate that the device is capable of collecting data at a temporal resolution sufficient for identifying individual water use events and analyzing water use at coarser temporal resolutions. This system is of special interest for water end use studies, future projections of residential water use, water infrastructure design, and for advancing our understanding of water use timing and behavior. The system’s hardware design and software are open source, are available for potential reuse, and can be customized for specific research needs.


2013 ◽  
Vol 02 (02) ◽  
pp. 1340008 ◽  
Author(s):  
R. M. GENET

Speckle interferometry of close double stars avoids seeing limitations through a series of diffraction-limited high speed observations made faster than the atmospheric coherence time scale. Electron multiplying CCD cameras have low read noise at high read speeds, making them ideal for speckle interferometry. A portable speckle camera system was developed based on relatively low cost, off-the-shelf components. The camera's modular components can be exchanged to adapt the system to a wide range of telescopes.


2012 ◽  
Vol 704 ◽  
pp. 1-4 ◽  
Author(s):  
John R. de Bruyn

AbstractA flowing granular material can behave like a collection of individual interacting grains or like a continuum fluid, depending in large part on the energy imparted to the grains. As yet, however, we have no general understanding of how or under what conditions the fluid limit is reached. Marston, Li & Thoroddsen (J. Fluid Mech., this issue, vol. 704, 2012, pp. 5–36) use high-speed imaging to investigate the ejection of grains from a granular bed due to the impact of a spherical projectile. Their high temporal resolution allows them to study the very fast processes that take place immediately following the impact. They demonstrate that for very fine grains and high impact energies, the dynamics of the ejecta is both qualitatively and quantitatively similar to what is seen in analogous experiments with fluid targets.


1997 ◽  
Vol 119 (2) ◽  
pp. 232-237 ◽  
Author(s):  
T. Chuenchom ◽  
S. Kota

Conventional hard automation such as linkage mechanisms and cam-driven mechanisms provide high speed capability at a low cost, but fail to provide the flexibility required in many industrial applications. On the other hand, for most manufacturing automation applications in high production industries, expensive multi-axis robots are employed for simple repetitive operations that require only limited flexibility. In order to provide a true middle ground between conventional mechanism-based hard automation and overly flexible anthropomorphic robots, we incorporate flexibility in conventional mechanisms, thereby creating “programmable mechanisms” or Adjustable Robotic Mechanisms (ARMs). This paper introduces the concept of ARMs and presents generalized analytical methods for designing adjustable mechanisms based on synthesis of adjustable dyads. The synthesis methods presented here, which are extensions of the well-known Burmester precision point theory, enable one to design multi-purpose mechanisms for multiple sets of precision points, thereby enabling conventional mechanisms to perform multiple tasks. The analytical synthesis method has been implemented in a computer program that generates all adjustable dyad solutions for given sets of precision points. Two or more adjustable dyads are assembled together to form a programmable linkage mechanism that performs multiple tasks. Synthesis formulations and a design example illustrating the analytical and computer-aided synthesis methods are presented.


2018 ◽  
Vol 224 ◽  
pp. 01020 ◽  
Author(s):  
Georgi M. Martinov ◽  
Akram Al Khoury ◽  
Ahed Issa

Nowadays, there is a big demand on using small sized CNC machine tools, which have low price tag, wide range of implementations, low manufacturing costs and can be used for educational purposes. These machines can achieve casual manufacturing routines, like milling and drilling in applications, where there is no need for high speed performances and super quality of products. In this work, we proposed a model of CNC for these machines and analysed its components and efficiency. The model consists of three main layers: CNC system (application layer), ARM based microcomputer as CAN master and controller (connecting layer) and Servo-Drive Step Motors (actuating layer).


Author(s):  
Daniel B. Hess ◽  
Brian D. Taylor ◽  
Allison C. Yoh

Bus rapid transit (BRT) is growing rapidly in popularity because it is viewed widely as an efficient and effective means to improve both transit service and patronage. This paper argues that two distinct views of BRT are emerging: ( a) BRT as a new form of high-speed, rubber-tired, rail-like rapid transit and ( b) BRT as a cost-effective way to upgrade both the quality and image of traditional fixed-route bus service. These two views carry different price tags because the cost of planning, constructing, and operating BRT depends on the complexity of new service features and on rises for BRT that offer service characteristics approaching those of light rail. This study fills a gap in the literature on the costs of BRT by examining in detail component costs–-actual costs for recently implemented services and projected costs for planned new services–-for a sample of BRT systems in North American cities. The study examined BRT costs of 14 planned and recently opened BRT systems to determine how the wide range of BRT service and technology configurations affect costs. The study found that although some of the most successful and popular new BRT systems are high-quality services operating in mixed traffic and implemented at relatively low cost, most BRT projects on the drawing boards are more elaborate, more expensive systems than many currently in service. Most new BRT projects emphasize elaborate LRT-type improvements to lines and stations in one or a few corridors rather than less splashy improvements (such as next-bus monitors, signal preemption, queue-jump lanes, and so forth) affecting more lines and modes in local transit networks. Among the 14 systems examined here, most could be characterized as light rail lite.


2021 ◽  
Vol 263 (2) ◽  
pp. 4418-4425
Author(s):  
Han Wu ◽  
Peng Zhou ◽  
Siyang Zhong ◽  
Xin Zhang ◽  
Kunyu Luo

Multi-copters or drones are engaged in a wide range of industrial applications for their flexibility, safety and low-cost. The noise emission is becoming an issue with the expanding applications, among which the propellers that drive the drones are the major sources of noise. In this work, the noise characteristics of small-scale propellers is experimentally investigated using the advanced rotor aerodynamics and aeroacoustics test platform in an anechoic chamber at the Hong Kong University of Science and Technology (HKUST). The study will focus on the representative off-the-shelf propellers. The rotor noise will be measured by a linear array with 20 microphones, and the aerodynamic forces will be acquired by using the high-accuracy load cells. The dependence of both the tonal and broadband noise radiation with the thrust and rotation speed at various conditions will be tested. The study will enhance our understanding of the noise features of the multi-rotor powered drones, and will provide us with a better understanding of the status of the drone noise impact on the environment.


2018 ◽  
Vol 10 (8) ◽  
pp. 2628
Author(s):  
Heekwon Yang ◽  
Byeol Kim ◽  
Joosung Lee ◽  
Yonghan Ahn ◽  
Chankil Lee

The communication technology ZigBee has been widely adopted in wireless sensor networks (WSNs) for a wide range of industrial applications. However, although ZigBee provides low-power, low-cost mesh networking, it cannot guarantee steady and predictable network performance as channels are time-variant and highly attenuated by man-made obstacles. The networks also suffer from interference, especially in the important 2.4 GHz industrial, scientific, and medical (ISM) band. These degraded channel characteristics increase the number of hops, thus increasing both the packet error rate and transmission delays. In this paper, we report the deployment of a ZigBee-based WSN inside an existing building duct system utilized for intelligent waste collection in an industrial environment. The Received Signal Strength (RSS) and path losses were measured, revealing that the duct communication channel acts as a very effective waveguide, providing a more reliable and consistent network performance than conventional free space channels.


2011 ◽  
Vol 225-226 ◽  
pp. 589-592
Author(s):  
Yan Liu ◽  
Ze Gang Ye

The current Synchro-to-Digital conversion (S/DC)with high reliability, high accuracy and widely used in the military field, but it has high cost and low tracking speed, not suitable for high speed and low-cost industrial applications. In this work, the principle of synchro and the harmonics of the synchro output signals are investigated. Multifunction S/DC software design using FFT algorithm and IIR digital filter technology is proposed. It Integrated many functions, such as angle position, harmonics analysis and filter, it also improved measurement accuracy and speed, reduced the cost. The simulation results by Matlab show that the method is feasible.


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