Materials for High Speed Circuit Boards

1987 ◽  
Vol 108 ◽  
Author(s):  
R. W. Seibold ◽  
R. T. Lamoureux ◽  
S. H. Goodman
Keyword(s):  
High Speed ◽  
Circuit Boards ◽  
The Past ◽  
Defense Systems ◽  
Hazardous Environments ◽  
Data Rates ◽  
The World

During the past five years, the computer you bought with 128 Kbytes of memory has been upgraded by the availability of 40 Mbyte storage and modems which allow instant access to databases around the world. The continuing need to perform more complex missions for modern defense systems in more hazardous environments will call for substantially higher data rates than are available today.

scholarly journals WebRTC - Realtime Communication for the Open Web Platform

Queue ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 77-93
Author(s):  
Niklas Blum ◽  
Serge Lachapelle ◽  
Harald Alvestrand
Keyword(s):  
High Speed ◽  
Network Access ◽  
The Past ◽  
Human Contact ◽  
High Speed Network ◽  
The World ◽  
Web Platform

In this time of pandemic, the world has turned to Internet-based, RTC (realtime communication) as never before. The number of RTC products has, over the past decade, exploded in large part because of cheaper high-speed network access and more powerful devices, but also because of an open, royalty-free platform called WebRTC. WebRTC is growing from enabling useful experiences to being essential in allowing billions to continue their work and education, and keep vital human contact during a pandemic. The opportunities and impact that lie ahead for WebRTC are intriguing indeed.

The Past of the Future of Computation

2018 ◽  
Author(s):  
James A. Anderson
Keyword(s):  
Artificial Intelligence ◽  
High Speed ◽  
The Other ◽  
Cognitive Tasks ◽  
Cognitive Tool ◽  
The Past ◽  
The World ◽  
The Future ◽  
Simple Step ◽  
A Current

Hand axes, language, and computers are tools that increase our ability to deal with the world. Computing is a cognitive tool and comes in several kinds: digital, analog, and brain-like. An analog telephone connects two telephones with a wire. Talking causes a current to flow on the wire. In a digital telephone the voltage is converted into groups of ones or zeros and sent at high speed from one telephone to the other. An analog telephone requires one simple step. A digital telephone requires several million discrete steps per second. Digital telephones work because the hardware has gotten much faster. Yet brains constructed of slow devices and using a few watts of power are competitive for many cognitive tasks. The important question is not why machines are becoming so smart but why humans are still so good. Artificial intelligence is missing something important probably based on hardware differences.

Asphalt in trackbed design

2020 ◽  
Author(s):  
Chrysoula Voulgari
Keyword(s):  
Parametric Analysis ◽  
High Speed ◽  
Base Layer ◽  
The Past ◽  
Traffic Loads ◽  
The World ◽  
High Speed Trains ◽  
Induced Stresses ◽  
Resistant Layer ◽  
Potential Use

<p>Conventional all granular trackbed has been in use around the world for many years, presenting good results although requiring a certain level of ongoing maintenance. Increasing traffic loads and volumes and particularly the introduction of high-speed trains in the last few decades, have resulted in the need for new approaches. To reduce train load-induced stresses in the track subgrade, one approach that has been introduced is the use of a Hot Mix Asphalt (HMA) layer as a partial or full replacement of the granular sub-ballast.</p><p>During the past few decades the use of HMA as a sub-ballast layer within the track structure has steadily increased until it has become standard practice in many countries around the world (USA, Japan, Germany, Italy etc.). The HMA mix is designed similarly to the base layer of highway pavements. Specifically, it is designed to be a medium modulus, flexible, low voids, fatigue resistant layer that will accommodate high tensile strains without cracking .</p><p>This paper provides a review of the potential use of an asphalt layer to replace the granular sub-ballast during the railway trackbed design.  A literature review of the use of asphalt in trackbed construction and a parametric analysis have been carried out to compare traditional ‘all granular’ and more recent asphalt layer solutions for different subgrade stiffnesses. </p><p>Results indicate various advantages of the use of asphalt in the trackbed; improving trackbed performance and decreasing the overall cost and environmental impact.</p>

scholarly journals Developments in GPR Based NDT for Ballastless Track of High-Speed Railways

2020 ◽  
Author(s):  
Xiaoting Xiao ◽  
Guiyun Tian ◽  
Dong Liu ◽  
Mark Robinson ◽  
Anthony Gallagher
Keyword(s):  
Concrete Structure ◽  
High Speed ◽  
Nondestructive Method ◽  
Experimental Results ◽  
Significant Challenge ◽  
The Past ◽  
Ballastless Track ◽  
The World ◽  
Network Analyser ◽  
Ground Penetrating

For the past decades, ballastless track has been developed and used successfully throughout the world. Due to the multi-layer concrete structure of a ballastless track, timely detection of problems becomes a significant challenge. Ground Penetrating Radar (GPR), as an effective nondestructive method, has been applied to ballastless track in the last ten years. This paper reviews the state-of-the-art of GPR for the ballastless track. The challenges and problems are highlighted and discussed. A Vector Network Analyser (VNA) based stepped-frequency GPR system is considered for the problems and detection requirements. The experimental results show that the proposed system can detect narrow cracks in the depth up to 50cm.

An Investigation into Permissions Requested by Mobile Banking on Android Platform

2018 ◽  
Vol 9 (2) ◽  
pp. 12-30
Author(s):  
Latifa Er-Rajy ◽  
M. Ahmed El Kiram
Keyword(s):  
Mobile Technology ◽  
High Speed ◽  
Mobile Apps ◽  
World Population ◽  
Mobile Banking ◽  
The Past ◽  
Man In The Middle ◽  
The World ◽  
User Data ◽  
Mobile Banking Applications

In the past, banking took place only inside bank rooms, which was a task for customers and bankers at the same time. But in our day, thanks to the high-speed development and growth of mobile technology, the mobile phone platform had the power to create great opportunities for customers of the physical bank due to its capabilities and coverage of the population; this can be proved by the number of mobile subscriptions that approximates the world population figures. In order to explore these opportunities, most banks have already launched their mobile apps or have redesigned the mobile version of their websites. Among the advantages of using mobile banking is that users have the ability to make banking transactions, online payments or transfers, anywhere and at any time. In this article, we investigated the danger of the permissions requested by mobile banking applications, their effects on sensitive user data and their relationship with the attack called “Man in the middle” and its different forms. We took Morocco as a case of study.

The on-line use of histogram data for high-speed correction and alignment of electron microscope images

1984 ◽  
Vol 42 ◽  
pp. 556-557
Author(s):  
William Krakow
Keyword(s):  
Power Spectrum ◽  
High Speed ◽  
Direct Memory Access ◽  
Digital Television ◽  
Contrast Transfer Function ◽  
The Past ◽  
High Resolution Tem ◽  
On Line ◽  
Correction Of Astigmatism ◽  
The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

An atomic-resolution microscope study of Al contracts on GaAs

1986 ◽  
Vol 44 ◽  
pp. 726-727
Author(s):  
Z. Liliental-Weber ◽  
C. Nelson ◽  
R. Ludeke ◽  
R. Gronsky ◽  
J. Washburn
Keyword(s):  
High Speed ◽  
Schottky Contacts ◽  
Detailed Knowledge ◽  
The Past ◽  
Semiconductor Interfaces ◽  
Deposited Metal ◽  
Microwave Applications ◽  
Free Interfaces ◽  
Potential Use

The properties of metal/semiconductor interfaces have received considerable attention over the past few years, and the Al/GaAs system is of special interest because of its potential use in high-speed logic integrated optics, and microwave applications. For such materials a detailed knowledge of the geometric and electronic structure of the interface is fundamental to an understanding of the electrical properties of the contact. It is well known that the properties of Schottky contacts are established within a few atomic layers of the deposited metal. Therefore surface contamination can play a significant role. A method for fabricating contamination-free interfaces is absolutely necessary for reproducible properties, and molecularbeam epitaxy (MBE) offers such advantages for in-situ metal deposition under UHV conditions

A basic introduction to image processing using NIH-Image as a model

1994 ◽  
Vol 52 ◽  
pp. 392-393
Author(s):  
John Mansfield
Keyword(s):  
Image Processing ◽  
Digital Image ◽  
Image Acquisition ◽  
Digital Instrument ◽  
Novice User ◽  
Nih Image ◽  
The Past ◽  
Digital World ◽  
The World ◽  
Instrument Control

Advances in camera technology and digital instrument control have meant that in modern microscopy, the image that was, in the past, typically recorded on a piece of film is now recorded directly into a computer. The transfer of the analog image seen in the microscope to the digitized picture in the computer does not mean, however, that the problems associated with recording images, analyzing them, and preparing them for publication, have all miraculously been solved. The steps involved in the recording an image to film remain largely intact in the digital world. The image is recorded, prepared for measurement in some way, analyzed, and then prepared for presentation.Digital image acquisition schemes are largely the realm of the microscope manufacturers, however, there are also a multitude of “homemade” acquisition systems in microscope laboratories around the world. It is not the mission of this tutorial to deal with the various acquisition systems, but rather to introduce the novice user to rudimentary image processing and measurement.

On the Symbolism of Rain in A Farewell to Arms

2018 ◽  
Keyword(s):  
Research Tool ◽  
The Past ◽  
The World ◽  
Farewell To Arms

This paper critically analyzes the symbolic use of rain in A Farewell to Arms (1929). The researcher has applied the Sapir-Whorf Hypothesis as a research tool for the analysis of the text. This hypothesis argues that the languages spoken by a person determine how one observes this world and that the peculiarities encoded in each language are all different from one another. It affirms that speakers of different languages reflect the world in pretty different ways. Hemingway’s symbolic use of rain in A Farewell to Arms (1929) is denotative, connotative, and ironical. The narrator and protagonist, Frederick Henry symbolically embodies his own perceptions about the world around him. He time and again talks about rain when something embarrassing is about to ensue like disease, injury, arrest, retreat, defeat, escape, and even death. Secondly, Hemingway has connotatively used rain as a cleansing agent for washing the past memories out of his mind. Finally, the author has ironically used rain as a symbol when Henry insists on his love with Catherine Barkley while the latter being afraid of the rain finds herself dead in it.

Profilometry. Using Corneo-scleral topography for scleral lens fitting

The Eye ◽  
2019 ◽  
Vol 21 (128) ◽  
pp. 19-22
Author(s):  
Gregory DeNaeyer
Keyword(s):  
Ocular Surface ◽  
World Wide ◽  
Contact Lenses ◽  
The Past ◽  
The World ◽  
The Future ◽  
The Way

The world-wide use of scleral contact lenses has dramatically increased over the past 10 year and has changed the way that we manage patients with corneal irregularity. Successfully fitting them can be challenging especially for eyes that have significant asymmetries of the cornea or sclera. The future of scleral lens fitting is utilizing corneo-scleral topography to accurately measure the anterior ocular surface and then using software to design lenses that identically match the scleral surface and evenly vault the cornea. This process allows the practitioner to efficiently fit a customized scleral lens that successfully provides the patient with comfortable wear and improved vision.

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