scholarly journals Corrigendum to “High-Accuracy Programmable Timing Generator with Wide-Range Tuning Capability”

VLSI Design ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-1
Author(s):  
Ting-Li Chu ◽  
Sin-Hong Yu ◽  
Chorng-Sii Hwang
Keyword(s):  
Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 284
Author(s):  
Yihsiang Chiu ◽  
Chen Wang ◽  
Dan Gong ◽  
Nan Li ◽  
Shenglin Ma ◽  
...  

This paper presents a high-accuracy complementary metal oxide semiconductor (CMOS) driven ultrasonic ranging system based on air coupled aluminum nitride (AlN) based piezoelectric micromachined ultrasonic transducers (PMUTs) using time of flight (TOF). The mode shape and the time-frequency characteristics of PMUTs are simulated and analyzed. Two pieces of PMUTs with a frequency of 97 kHz and 96 kHz are applied. One is used to transmit and the other is used to receive ultrasonic waves. The Time to Digital Converter circuit (TDC), correlating the clock frequency with sound velocity, is utilized for range finding via TOF calculated from the system clock cycle. An application specific integrated circuit (ASIC) chip is designed and fabricated on a 0.18 μm CMOS process to acquire data from the PMUT. Compared to state of the art, the developed ranging system features a wide range and high accuracy, which allows to measure the range of 50 cm with an average error of 0.63 mm. AlN based PMUT is a promising candidate for an integrated portable ranging system.


Author(s):  
Soumya Raychaudhuri

Successful use of text mining algorithms to facilitate genomics research hinges on the ability to recognize the names of genes in scientific text. In this chapter we address the critical issue of gene name recognition. Once gene names can be recognized in the scientific text, we can begin to understand what the text says about those genes. This is a much more challenging issue than one might appreciate at first glance. Gene names can be inconsistent and confusing; automated gene name recognition efforts have therfore turned out to be quite challenging to implement with high accuracy. Gene name recognition algorithms have a wide range of useful applications. Until this chapter we have been avoiding this issue and have been using only gene-article indices. In practice these indices are manually assembled. Gene name recognition algorithms offer the possibility of automating and expediting the laborious task of building reference indices. Article indices can be built that associate articles to genes based on whether or not the article mentions the gene by name. In addition, gene name recognition is the first step in doing more detailed sentence-by-sentence text analysis. For example, in Chapter 10 we will talk about identifying relationships between genes from text. Frequently, this requires identifying sentences refering to two gene names, and understanding what sort of relationship the sentence is describing between these genes. Sophisticated natural language processing techniques to parse sentences and understand gene function cannot be done in a meaningful way without recognizing where the gene names are in the first place. The major concepts of this chapter are presented in the frame box. We begin by describing the commonly used strategies that can be used alone or in concert to identify gene names. At the end of the chapter we introduce one successful name finding algorithm that combines many of the different strategies. There are several commonly used approaches that can be exploited to recognize gene names in text (Chang, Shutze, et al. 2004). Often times these approaches can be combined into even more effective multifaceted algorithms.


Author(s):  
Mohammad Javad Doregiraei ◽  
Hossein Moeinkhah ◽  
Jafar Sadeghi

The accurate modeling of electrical impedance over a wide range of frequency is essential for precise dynamic modeling and control problems of Electroactive Polymer (EAP) actuators. Recently, fractional order modeling has attracted more attention due to the high accuracy. This paper deals with a fractional order electrical impedance model and its identification procedure for a class of EAP actuator named Ionic Polymer Metal Composite (IPMC). To take IPMC’s fractional characteristic into account, constant phase element (CPE) is used to construct a model structure according to Electrochemical Impedance Spectroscopy (EIS). By employing the Levy’s method in combination with genetic optimization algorithm, the unknown parameters of the resulting fractional transfer function are identified. Finally the proposed model is verified, by comparing with experimental EIS data. The results show that the fractional order model has high accuracy for representing the electrical impedance of IPMC actuator. The proposed modeling procedure is general and can also be used for any type of EAPs.


2011 ◽  
Vol 230-232 ◽  
pp. 235-240
Author(s):  
Chuan De Zhou ◽  
Li Lai

This paper researchs the space vector change and machine vision recognition based on plane target cooperation identification.Then establishes plane target imaging model, space attitude measurement algorithm and software flow, which are utilized in the measurement of automobile four-wheel location. The results indicate that this method is feasible in the automobile four-wheel location technology with the advantages of good anti-interference, fast speed, wide range and high accuracy.


Author(s):  
Arijit Sen ◽  
Amin Al-Habaibeh

AbstractEstimating the U-value of walls of buildings is a key process to evaluate the overall thermal performance. Low U-value in buildings is desired in order to keep heat within the envelop and consume less energy in heating. Addressing the limitations in the currently used U-value estimation techniques, this paper proposes a novel approach for estimating the U-value of the envelop of buildings using infrared thermography and Artificial Neural Network (ANN) with the application of a point heat source. The novel system is calibrated by training the ANN in a lab environment using a wide range of samples with multi-layers to be able to estimate the in situ U-value of walls in real buildings during field work with relatively high accuracy.


2018 ◽  
Vol 20 (91) ◽  
pp. 51-56
Author(s):  
M. Dorosh-Kizym ◽  
O. Dadak ◽  
T. Gachek

In recent years, e-commerce has been able to penetrate practically in all spheres of life of the population and in Ukraine. The domestic e-commerce market is only at the inception stage, but at the same time it has a significant potential for development. The Internet and related technologies continue to actively and effectively interfere with logistics. Modern logistics technologies are inextricably linked with intensive information exchange. Due to the timely receipt of information, high accuracy, speed and consistency of goods exchange in logistic chains are ensured. Over the past few years, the structure of the logistics space of the Internet has significantly changed, which was reflected in the transformation of the content of logistics-oriented sites. If advertising information dominated previously, now, often in interactive mode, organizational, reference and design services are presented. Business commerce, advertising, production and modern technologies of the Internet are all more vibrant in all strata of human life. Today, the penetration of Internet technologies into business and economics is growing rapidly. The Internet is now – a huge market with a multi-level structure with abyss of opportunities that has an incredible potential for solving problems and business. This penetration also affects logistics. Logistics technologies are unthinkable without intensive information exchange. It is owing to the timely receipt of information that provides high accuracy, speed and consistency of turnover in logistics chains. Therefore, logistics as a modern scientific and practical direction of commodity distribution is also rapidly mastering these technologies and in its own way is equipped on the network. The Internet as a technology of global open networks is the best means to attract a wide range of logistics service users. With the help of this technology can be provided: advertising company; providing a list of services and price lists; account of regular clients and companions; providing consumers with the necessary documents on a paid and free basis; interactive advisory service; counteragent search service; registries of logistics companies and the database of information and logistics resources in the network; electronic freight; monitoring of goods and vehicles; virtual agency and forwarding. Today, the process of accumulation of logistics resources in the Internet has reached a level that allows us to talk about the process of forming virtual logistics centers (commercial or conditional commercial). This, in turn, with further development, can form a single logistics information space on the Internet.


2020 ◽  
Author(s):  
Menno Veerman ◽  
Robert Pincus ◽  
Caspar van Leeuwen ◽  
Damian Podareanu ◽  
Robin Stoffer ◽  
...  

<p>A fast and accurate treatment of radiation in meteorological models is essential for high quality simulations of the atmosphere. Despite our good understanding of the processes governing the transfer of radiation, full radiative transfer solvers are computationally extremely expensive. In this study, we use machine learning to accelerate the optical properties calculations of the Rapid Radiative Transfer Models for General circulation model applications - Parallel (RRTMGP). These optical properties control the absorption, scattering and emission of radiation within each grid cell. We train multiple neural networks that get as input the pressure, temperature and concentrations of water vapour and ozone of each grid cell and together predict all 224 or 256 quadrature points of each optical property. All networks are multilayer perceptrons and we test various network sizes to assess the trade-off between the accuracy of a neural network and its computational costs. We train two different sets of neural networks. The first set (generic) is trained for a wide range of atmospheric conditions, based on the profiles chosen by the Radiative Forcing Model Intercomparison Project (RFMIP). The second set (case-specific) is trained only for the range in temperature, pressure and moisture found in one large-eddy simulation based on a case with shallow convection over a vegetated surface. This case-specific set is used to explore the possible performance gains of case-specific tuning.</p><p>Most neural networks are able to predict the optical properties with high accuracy. Using a network with 2 hidden layers of 64 neurons, predicted optical depths in the longwave spectrum are highly accurate (R<sup>2 </sup>> 0.99). Similar accuracies are achieved for the other optical properties. Subsequently, we take a set of 100 atmospheric profiles and calculate profiles of longwave and shortwave radiative fluxes based on the optical properties predicted by the neural networks. Compared to fluxes based on the optical properties computed by RRTMGP, the downwelling longwave fluxes have errors within 0.5 W m<sup>-2</sup> (<1%) and an average error of -0.011 W m<sup>-2</sup> at the surface. The downwelling shortwave fluxes have an average error of -0.0013 W m<sup>-2</sup> at the surface. Using Intel’s Math Kernel Library’s (MKL) BLAS routines to accelerate matrix multiplications, our implementation of the neural networks in RRTMGP is about 4 times faster than the original optical properties calculations. It can thus be concluded that neural networks are able to emulate the calculation of optical properties with high accuracy and computational speed.</p>


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