<title>Write-Once optical technology: how mass storage and random-access retrieval have paved the road from horizontal to vertical applications</title>

Output-only methodologies are nowadays well established to extract modal parameters in many areas of engineering, such as civil, mechanical and aeronautical. In the past, civil engineering tests have been mainly developed for road bridges, with the vehicle passage over the bridge deck representing the main source of excitation with some contribution given by the ambient noise. In the road bridge cases, the excitation is considered to be a function of the road surface roughness, the vehicles speed, the weight and suspension vehicles characteristics, and also the random access of the vehicles over the bridge, whilst for the railway case, not all these issues are correctly addressed, and other characteristics rise-up, possibly advantageous for a correct identification process; to demonstrate this statement, we can bear in mind how the random access of the vehicles becomes meaningless for railway bridges, the single train being a quasi deterministic source; furthermore, the influence of the train weight should be considered if compared to usual road vehicles. Since output-only techniques are conceived for random excitation noise, their use in these conditions is considerably stressed and special care, or alternative techniques, has to be considered to avoid errors. In this sense, the bridge reference model becomes more important and some special techniques have to be developed.

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A process for retrieval of data from a compiled star catalogue

International Astronomical Union Colloquium ◽

10.1017/s0252921100082804 ◽

1982 ◽

Vol 64 ◽

pp. 123-125

Author(s):

William Stein

Keyword(s):

Data Base ◽

Execution Time ◽

Gamma Ray ◽

Attitude Determination ◽

Random Access ◽

Initial Step ◽

Space Vehicles ◽

Mass Storage ◽

Star Catalogue ◽

Star Images

For certain space vehicles there is a need to accurately determine vehicle attitude. Some of these spacecraft, such as NASA’s planned LANDSAT-D and Gamma Ray Explorer, will use observations from star sensors to determine fine attitude. One input to the attitude determination software is a specialized stellar data base. The initial step in this software is to identify and match the star images with catalogue stars. The Naval Surface Weapons Center (NSWC) has compiled a special star catalogue for such applications. This paper describes the criteria for the NSWC catalogue and how it is utilized. Because of the large number of stars available, a subset can be divided into cells defined by mission criteria. The cells are stored as a random access mass storage file, thus allowing quick access to the information. This greatly reduces execution time for the software. One scheme for accessing stars from mass storage is described.

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Commercial introduction of digital optical disk technology

Journal of Information Science ◽

10.1177/016555158400900503 ◽

1984 ◽

Vol 9 (5) ◽

pp. 209-215 ◽

Cited By ~ 2

Author(s):

Jean Ledieu

Keyword(s):

Storage Capacity ◽

Storage Systems ◽

Electronics Industry ◽

Optical Disk ◽

Information Storage ◽

Mass Storage ◽

Optical Technology ◽

Accelerated Growth ◽

Commercial Introduction

The accelerated growth of information and the rapid devel opment of digital coding techniques have given rise to a new need for greater information storage. This has led to the expansion of the peripheral storage market which today represents one of the fastest growing sectors of the electronics industry. The rise of commercial optical technology is creating dramatic increases in information storage capacity, particularly m the area of graphics storage. This technology is presently being introduced to the high-end and midrange drives market but will be expanded to low-end and mass-storage systems production (i.e., 'juke boxes') as early as 1985.

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A Built-in Self-Test System for External DRAM

Mathematical Problems of Computer Science ◽

10.51408/1963-0061 ◽

2020 ◽

pp. 80-87

Author(s):

Gor Abgaryan

Keyword(s):

Integrated Circuits ◽

High Speed ◽

High Efficiency ◽

Random Access ◽

Test System ◽

Mass Storage ◽

Access Memory ◽

Yield And Quality ◽

Self Test ◽

Built In Self Test

In the fast-growing Integrated Circuits (IC) industry, memory is one of the few keys to have systems with improved and fast performance. Only one transistor and a capacitor are required for Dynamic Random-Access Memory (DRAM) bit. It is widely used for mass storage. Although the high-efficiency tests are performed to provide the reliability of the memories, maintaining acceptable yield and quality is still the most critical task. To perform a high-speed effective test of DRAM memories, a built-in self-test (BIST) mechanism is proposed.

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Spintronics - A Dive Into the Future

International Journal of Scientific Research in Computer Science Engineering and Information Technology ◽

10.32628/cseit206477 ◽

2020 ◽

pp. 433-440

Author(s):

Shahzeb Hussain ◽

Shaayan Hussain

Keyword(s):

Giant Magnetoresistance ◽

New Technologies ◽

Random Access ◽

Spin Transfer Torque ◽

Spin Transfer ◽

Effective Control ◽

Hard Drives ◽

The Road ◽

A Charge ◽

Dependent Transport

We already know that electrons have a charge along with a spin, but until recently, these two have been considered separately. The motion of electric charge is considered as the heart of electronic circuits, and the flow of electron spin plays a crucial role in spintronic circuits. Adding the spin degree of freedom provides new capabilities, new effects, and new functionalities. It all started with the discovery of the Giant Magnetoresistance (GMR) in 1988, which opened the road to an effective control of the motion of the electron charges by focusing on their spin through the orientation of magnetization. Today, spintronics has entered into almost every household as the read sensors for the hard drives present in every desktop and most laptops. Magnetic Random Access Memory (MRAM) and Spin Transfer Torque (STT) RAM are replacing Static RAM where ultra-dense memories are not required. Soon these spintronic memories will penetrate the cell phone market because they offer lower power and are non-volatile. The potential held by Spintronics is very promising for new advancements in science and technology in the 21st century. This paper discusses the evolution of spintronics from the initial research of spin-dependent transport in ferromagnetic materials to the discovery of the giant magnetoresistance and to the most recent advances. Today, this field of research is extending considerably, with very encouraging new technologies like the phenomena of spin transfer, molecular spintronics, nanoscale spintronics, and single-electron spintronics.

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The bright future of digital imaging in scanning electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149672 ◽

1993 ◽

Vol 51 ◽

pp. 768-769

Author(s):

M. T. Postek ◽

A. E. Vladar

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Digital Imaging ◽

High Speed ◽

High Performance ◽

Mass Storage ◽

Analog To Digital ◽

Central Processing ◽

Digital Imaging Technology ◽

Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.

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Seeking to uncover biology's chemical roots

Emerging Topics in Life Sciences ◽

10.1042/etls20190012 ◽

2019 ◽

Vol 3 (5) ◽

pp. 435-443 ◽

Cited By ~ 3

Author(s):

Addy Pross

Keyword(s):

Environmental Changes ◽

Biological Systems ◽

Significant Development ◽

The Road ◽

Physical Chemical ◽

Systems Chemistry ◽

Biological World ◽

Inanimate Matter ◽

The Origin Of Life ◽

Opening Up

Despite the considerable advances in molecular biology over the past several decades, the nature of the physical–chemical process by which inanimate matter become transformed into simplest life remains elusive. In this review, we describe recent advances in a relatively new area of chemistry, systems chemistry, which attempts to uncover the physical–chemical principles underlying that remarkable transformation. A significant development has been the discovery that within the space of chemical potentiality there exists a largely unexplored kinetic domain which could be termed dynamic kinetic chemistry. Our analysis suggests that all biological systems and associated sub-systems belong to this distinct domain, thereby facilitating the placement of biological systems within a coherent physical/chemical framework. That discovery offers new insights into the origin of life process, as well as opening the door toward the preparation of active materials able to self-heal, adapt to environmental changes, even communicate, mimicking what transpires routinely in the biological world. The road to simplest proto-life appears to be opening up.

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