To see the other types of publications on this topic, follow the link: Magnetic memory (Computers).
Journal articles on the topic 'Magnetic memory (Computers)'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Magnetic memory (Computers).'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Carley, L. Richard, James A. Bain, Gary K. Fedder, et al. "Single-chip computers with microelectromechanical systems-based magnetic memory (invited)." Journal of Applied Physics 87, no. 9 (2000): 6680–85. http://dx.doi.org/10.1063/1.372807.
Full text
2
Md Rakibul Karim Akanda, D’Mytri Wiggs, and Nathaniel Zepeda. "Calculating magnetic properties of two-dimensional materials for memory applications." International Journal of Science and Research Archive 11, no. 1 (2024): 613–26. http://dx.doi.org/10.30574/ijsra.2024.11.1.0098.
Full textAbstract:
Calculating magnetic properties of two-dimensional materials is crucial for implementing memory devices (like USB drive, RAM, hard disk drive of computers) having reduced size. Two dimensional materials can be implemented as a thin film which can reduce the size of memory devices. These materials as well as devices made with magnetic two-dimensional materials are of current research interest in industry and academia. From the materials project database, crystal structure file of 30 two dimensional materials have been downloaded to calculate their magnetic properties. BURAI Quantum espresso software has been used to extract magnetic properties of 30 two dimensional (2D) materials. These 30 materials have magnetic Fe, Ni, Co, Mn, and Cr atoms in their molecular structure. Magnetic materials play a key and vital role in today’s modern-day technology. There are five different types of magnetic materials. The classification magnetic materials are diamagnetism, paramagnetic, ferromagnetism, ferrimagnetism, and anti-ferromagnetism. Total energy of different magnetic configurations has been calculated to find the most stable magnetic configurations of these materials.
3
Ou, Qiao-Feng, Bang-Shu Xiong, Lei Yu, Jing Wen, Lei Wang, and Yi Tong. "In-Memory Logic Operations and Neuromorphic Computing in Non-Volatile Random Access Memory." Materials 13, no. 16 (2020): 3532. http://dx.doi.org/10.3390/ma13163532.
Full textAbstract:
Recent progress in the development of artificial intelligence technologies, aided by deep learning algorithms, has led to an unprecedented revolution in neuromorphic circuits, bringing us ever closer to brain-like computers. However, the vast majority of advanced algorithms still have to run on conventional computers. Thus, their capacities are limited by what is known as the von-Neumann bottleneck, where the central processing unit for data computation and the main memory for data storage are separated. Emerging forms of non-volatile random access memory, such as ferroelectric random access memory, phase-change random access memory, magnetic random access memory, and resistive random access memory, are widely considered to offer the best prospect of circumventing the von-Neumann bottleneck. This is due to their ability to merge storage and computational operations, such as Boolean logic. This paper reviews the most common kinds of non-volatile random access memory and their physical principles, together with their relative pros and cons when compared with conventional CMOS-based circuits (Complementary Metal Oxide Semiconductor). Their potential application to Boolean logic computation is then considered in terms of their working mechanism, circuit design and performance metrics. The paper concludes by envisaging the prospects offered by non-volatile devices for future brain-inspired and neuromorphic computation.
4
McKemmish, Laura K., David J. Kedziora, Graham R. White, Noel S. Hush, and Jeffrey R. Reimers. "Frequency-based Quantum Computers from a Chemist's Perspective." Australian Journal of Chemistry 65, no. 5 (2012): 512. http://dx.doi.org/10.1071/ch12053.
Full textAbstract:
Quantum computer elements are often designed and tested using molecular or nanoscopic components that form registers of qubits in which memory is stored and information processed. Often such registers are probed and manipulated using frequency-based techniques such as nuclear-magnetic resonance spectroscopy. A major challenge is to design molecules to act as these registers. We provide a basis for rational molecular design through consideration of the generic spectroscopic properties required for quantum computing, bypassing the need for intricate knowledge of the way these molecules are used spectroscopically. Designs in which two-qubit gate times scale similarly to those for one-qubit gates are presented. The specified spectroscopic requirements are largely independent of the type of spectroscopy used (e.g. magnetic resonance or vibrational) and are often independent of technical details of the application (e.g. broadband or high-resolution spectroscopy). This should allow the design of much larger quantum registers than have currently been demonstrated.
5
Wang, Frank Zhigang. "Beyond Memristors: Neuromorphic Computing Using Meminductors." Micromachines 14, no. 2 (2023): 486. http://dx.doi.org/10.3390/mi14020486.
Full textAbstract:
Resistors with memory (memristors), inductors with memory (meminductors) and capacitors with memory (memcapacitors) play different roles in novel computing architectures. We found that a coil with a magnetic core is an inductor with memory (meminductor) in terms of its inductance L(q) being a function of charge q. The history of the current passing through the coil is remembered by the magnetization inside the magnetic core. Such a meminductor can play a unique role (that cannot be played by a memristor) in neuromorphic computing, deep learning and brain-inspired computers since the time constant (t0=LC) of a neuromorphic RLC circuit is jointly determined by the inductance L and capacitance C, rather than the resistance R. As an experimental verification, this newly invented meminductor was used to reproduce the observed biological behavior of amoebae (the memorizing, timing and anticipating mechanisms). In conclusion, a beyond-memristor computing paradigm is theoretically sensible and experimentally practical.
6
Donahue, M. J. "Parallelizing a Micromagnetic Program for Use on Multiprocessor Shared Memory Computers." IEEE Transactions on Magnetics 45, no. 10 (2009): 3923–25. http://dx.doi.org/10.1109/tmag.2009.2023866.
Full text
7
Murray, Keith S. "Recent Advances in Molecular Magnetic Materials." Australian Journal of Chemistry 62, no. 9 (2009): 1081. http://dx.doi.org/10.1071/ch09260.
Full textAbstract:
This review describes advances made in three areas of molecular magnetic materials of the types A: extended frameworks (coordination polymers) showing long-range magnetic order, B: spin-coupled clusters with emphasis on single molecule magnets and (n × n) grid species, C: polynuclear spin-switching (spin crossover) compounds of FeII with emphasis on dinuclear compounds and one-dimensional (1D) and three-dimensional (3D) (framework) materials, including porous ‘hybrid’ systems. The work of the author and his group is largely used to provide examples, together with results from other groups and collaborators that are included for comparison and completeness. Supramolecular aspects such as cluster–cluster and chain–chain interactions are discussed where relevant. A brief discussion is also given of the recent studies, carried out elsewhere, dealing with aspects of spintronics and the possible future relevance to molecular computers (type B materials) and with memory and other device possibilities (type C materials)
8
Simoni, Mario, Giovanni Amedeo Cirillo, Giovanna Turvani, Mariagrazia Graziano, and Maurizio Zamboni. "Towards Compact Modeling of Noisy Quantum Computers: A Molecular-Spin-Qubit Case of Study." ACM Journal on Emerging Technologies in Computing Systems 18, no. 1 (2022): 1–26. http://dx.doi.org/10.1145/3474223.
Full textAbstract:
Classical simulation of Noisy Intermediate Scale Quantum computers is a crucial task for testing the expected performance of real hardware. The standard approach, based on solving Schrödinger and Lindblad equations, is demanding when scaling the number of qubits in terms of both execution time and memory. In this article, attempts in defining compact models for the simulation of quantum hardware are proposed, ensuring results close to those obtained with standard formalism. Molecular Nuclear Magnetic Resonance quantum hardware is the target technology, where three non-ideality phenomena—common to other quantum technologies—are taken into account: decoherence, off-resonance qubit evolution, and undesired qubit-qubit residual interaction. A model for each non-ideality phenomenon is embedded into a MATLAB simulation infrastructure of noisy quantum computers. The accuracy of the models is tested on a benchmark of quantum circuits, in the expected operating ranges of quantum hardware. The corresponding outcomes are compared with those obtained via numeric integration of the Schrödinger equation and the Qiskit’s QASMSimulator. The achieved results give evidence that this work is a step forward towards the definition of compact models able to provide fast results close to those obtained with the traditional physical simulation strategies, thus paving the way for their integration into a classical simulator of quantum computers.
9
Hong, Jeongmin, Brian Lambson, Scott Dhuey, and Jeffrey Bokor. "Experimental test of Landauer’s principle in single-bit operations on nanomagnetic memory bits." Science Advances 2, no. 3 (2016): e1501492. http://dx.doi.org/10.1126/sciadv.1501492.
Full textAbstract:
Minimizing energy dissipation has emerged as the key challenge in continuing to scale the performance of digital computers. The question of whether there exists a fundamental lower limit to the energy required for digital operations is therefore of great interest. A well-known theoretical result put forward by Landauer states that any irreversible single-bit operation on a physical memory element in contact with a heat bath at a temperature T requires at least kBT ln(2) of heat be dissipated from the memory into the environment, where kB is the Boltzmann constant. We report an experimental investigation of the intrinsic energy loss of an adiabatic single-bit reset operation using nanoscale magnetic memory bits, by far the most ubiquitous digital storage technology in use today. Through sensitive, high-precision magnetometry measurements, we observed that the amount of dissipated energy in this process is consistent (within 2 SDs of experimental uncertainty) with the Landauer limit. This result reinforces the connection between “information thermodynamics” and physical systems and also provides a foundation for the development of practical information processing technologies that approach the fundamental limit of energy dissipation. The significance of the result includes insightful direction for future development of information technology.
10
Dahal, Bishnu R., Andrew Grizzle, Christopher D’Angelo, Vincent Lamberti, and Pawan Tyagi. "Competing Easy-Axis Anisotropies Impacting Magnetic Tunnel Junction-Based Molecular Spintronics Devices (MTJMSDs)." International Journal of Molecular Sciences 23, no. 22 (2022): 14476. http://dx.doi.org/10.3390/ijms232214476.
Full textAbstract:
Molecular spintronics devices (MSDs) attempt to harness molecules’ quantum state, size, and configurable attributes for application in computer devices—a quest that began more than 70 years ago. In the vast number of theoretical studies and limited experimental attempts, MSDs have been found to be suitable for application in memory devices and futuristic quantum computers. MSDs have recently also exhibited intriguing spin photovoltaic-like phenomena, signaling their potential application in cost-effective and novel solar cell technologies. The molecular spintronics field’s major challenge is the lack of mass-fabrication methods producing robust magnetic molecule connections with magnetic electrodes of different anisotropies. Another main challenge is the limitations of conventional theoretical methods for understanding experimental results and designing new devices. Magnetic tunnel junction-based molecular spintronics devices (MTJMSDs) are designed by covalently connecting paramagnetic molecules across an insulating tunneling barrier. The insulating tunneling barrier serves as a mechanical spacer between two ferromagnetic (FM) electrodes of tailorable magnetic anisotropies to allow molecules to undergo many intriguing phenomena. Our experimental studies showed that the paramagnetic molecules could produce strong antiferromagnetic coupling between two FM electrodes, leading to a dramatic large-scale impact on the magnetic electrode itself. Recently, we showed that the Monte Carlo Simulation (MCS) was effective in providing plausible insights into the observation of unusual magnetic domains based on the role of single easy-axis magnetic anisotropy. Here, we experimentally show that the response of a paramagnetic molecule is dramatically different when connected to FM electrodes of different easy-axis anisotropies. Motivated by our experimental studies, here, we report on an MCS study investigating the impact of the simultaneous presence of two easy-axis anisotropies on MTJMSD equilibrium properties. In-plane easy-axis anisotropy produced multiple magnetic phases of opposite spins. The multiple magnetic phases vanished at higher thermal energy, but the MTJMSD still maintained a higher magnetic moment because of anisotropy. The out-of-plane easy-axis anisotropy caused a dominant magnetic phase in the FM electrode rather than multiple magnetic phases. The simultaneous application of equal-magnitude in-plane and out-of-plane easy-axis anisotropies on the same electrode negated the anisotropy effect. Our experimental and MCS study provides insights for designing and understanding new spintronics-based devices.
11
ABELSON, HAROLD, ANDREW A. BERLIN, JACOB KATZENELSON, et al. "THE SUPERCOMPUTER TOOLKIT: A GENERAL FRAMEWORK FOR SPECIAL-PURPOSE COMPUTING." International Journal of High Speed Electronics and Systems 03, no. 03n04 (1992): 337–61. http://dx.doi.org/10.1142/s0129156492000138.
Full textAbstract:
The Supercomputer Toolkit is a family of hardware modules (processors, memory, interconnect, and input-output devices) and a collection of software modules (compilers, simulators, scientific libraries, and high-level front ends) from which high-performance special-purpose computers can be easily configured and programmed. Although there are many examples of special-purpose computers (see Ref. 4), the Toolkit approach is different in that our aim is to construct these machines from standard, reusable parts. These are combined by means of a user-reconfigurable, static interconnect technology. The Toolkit’s software support, based on novel compilation techniques, produces extremely high-performance numerical code from high-level language input. We have completed fabrication of the Toolkit processor module, and several critical software modules. An eight-processor configuration is running at MIT. We have used the prototype Toolkit to perform a breakthrough computation of scientific importance—an integration of the motion of the Solar System that extends previous results by nearly two orders of magnitude. While the Toolkit project is not complete, we believe our results show evidence that generating special-purpose computers from standard modules can be an important method of performing intensive scientific computing. This paper briefly describes the Toolkit’s hardware and software modules, the Solar System simulation, conclusions and future plans.
12
Elías, Matías W., Fabio I. Zyserman, Marina Rosas-Carbajal, and María Constanza Manassero. "Three-dimensional modelling of controlled source electro-magnetic surveys using non-conforming finite element methods." Geophysical Journal International 229, no. 2 (2021): 1133–51. http://dx.doi.org/10.1093/gji/ggab524.
Full textAbstract:
SUMMARY The controlled source electro-magnetic (CSEM) method is increasingly used for in-land and off-shore subsurface characterization. Given its complex dependence between data and the parameters of interest, there is a crucial need for performant numerical algorithms that can simulate the CSEM response of 3-D geological structures. Here, we present two finite element (FE) algorithms for simulating the CSEM response in 3-D media with isotropic conductivity. A primary/secondary field approach is used to avoid the singularity introduced by the source. The primary field is computed semi-analytically for a horizontally layered model and different sources. The secondary field is obtained by discretizing the diffusive frequency-domain Maxwell’s equations with non-conforming FE. The two numerical algorithms are specifically designed to work on distributed-memory computers: (1) an iterative procedure with domain decomposition and (2) a direct and global algorithm. We evaluate their performance by computing their speed up on parallel processors, and solving problems with realistic conductivity structures. We also compare the accuracy of the solutions with published results on canonical models. The results shown here demonstrate the functionality of the two methodologies presented for specific cases when computing 3-D CSEM solutions.
13
ZIPPEL, RICHARD. "THE DATA STRUCTURE ACCELERATOR ARCHITECTURE." International Journal of High Speed Electronics and Systems 07, no. 04 (1996): 533–71. http://dx.doi.org/10.1142/s012915649600030x.
Full textAbstract:
We present a heterogeneous architecture that contains a fine grained, massively parallel SIMD component called the data structure accelerator and demonstrate its use in a number of problems in computational geometry including polygon filling and convex hull. The data structure accelerator is extremely dense and highly scalable. Systems of 106 processing elements can be embedded in workstations and personal computers, without dramatically changing their cost. These components are intended for use in tandem with conventional single sequence machines and with small scale, shared memory multiprocessors. A language for programming these heterogeneous systems is presented that smoothly incorporates the SIMD instructions of the data structure accelerator with conventional single sequence code. We then demonstrate how to construct a number of higher level primitives such as maximum and minimum, and apply these tools to problems in logic and computational geometry. For computational geometry problems, we demonstrate that simple algorithms that take advantage of the parallelism available on a data structure accelerator perform as well or better than the far more complex algorithms which are needed for comparable efficiency on single sequence computers.
14
Bondarev, A. V., and V. N. Efanov. "ANALYSIS OF DYNAMIC PROCESSES IN NANOELECTRONIC STRUCTURES BASED ON MEMRESISTIVE ELEMENTS." Izvestiya of Samara Scientific Center of the Russian Academy of Sciences 23, no. 2 (2021): 91–97. http://dx.doi.org/10.37313/1990-5378-2021-23-2-91-97.
Full textAbstract:
The emergence of recently a wide range of nanoelectronic components is expanding the possibilities of information and computing systems. First of all, it concerns supercomputers with Petaflopovaya productivity. To achieve such performance on the basis of modern microelectronic devices, computing complexes are created, combining up to 100 thousand processors that consume about 100 megawatts of electrical energy and occupy about 300 square meters. A significant increase in productivity, reduction of energy consumption and a decrease in mass-dimensional indicators can be ensured in the transition from microelectronic to a nanoelectronic element base. For such promising nanoelectronic components include memristors. A memristor (from memory — memory, and resistor-electrical resistance) is a passive element in microelectronics that can change its resistance depending on the charge flowing through it. For a long time, the memristor was considered a theoretical model [7], which cannot be implemented in practice, until the first sample of the element demonstrating the properties of the memristor was created in 2008 by a team of scientists led by R. S. Williams in the research laboratory of Hewlett-Packard. The device does not store charge like a capacitor, does not support magnetic flux like an inductor. The change in the properties of the device is provided by chemical reactions in a thin two-layer film of titanium dioxide (5 nm). One layer of the device film is slightly depleted of oxygen and oxygen vacancies migrate between the layers when the voltage changes. This implementation of the memristor belongs to the class of nanoion devices. The observed phenomenon of hysteresis in the memristor allows it to be used, among other things, as a memory cell [9, 10-15, 20-21]. The already studied properties of memristors allow us to say that on their basis it is possible to create computers of a fundamentally new architecture, significantly exceeding semiconductor ones in performance. Due to the regular structure of intersecting nanowires, memristor fabrication is quite simple, especially in comparison with the complex structure of modern processors based on CMOS technology. As a result, the write / read time in the memristor memory cell does not exceed 5 ns. The number of read / write cycles exceeds 1012, and the storage time of information is more than 10 years. All this suggests that memristor memory will become the only type of computer memory. However, the use of such elements in real-life conditions leads to the fact that the electrical parameters of these devices vary over a wide range. This uncertainty in characteristics complicates circuit analysis and the entire design process for electronic devices that include memristor components. In this regard, the problem of assessing the stability of nanoelectronic structures based on memresistive elements under conditions of uncertain external influences is urgent.
15
Jaloliddinzoda, Muhammadyusuf, Sergey F. Marenkin, Alexey I. Ril’, Mikhail G. Vasil’ev, Alexander D. Izotov, and Denis E. Korkin. "Synthesis of bulk crystals and thin films of the ferromagnetic MnSb." Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases 23, no. 3 (2021): 387–95. http://dx.doi.org/10.17308/kcmf.2021.23/3530.
Full textAbstract:
High-temperature ferromagnets are widely used on a practical level. Based on them, magnetic memory for computers and various types of magnetic field sensors are created. Therefore, bulk ingots and thin-film samples of ferromagnet manganese antimonide (MnSb) with a high Curie point are of great interest, both from the practical and fundamental sides. Manganese antimonide films are obtained in hybrid structures using molecular-beam epitaxy. The thickness of the films does not exceed tens of nanometers. Despite their high sensitivity to magnetic fields, their small thickness prevents them from being used as magnetic field sensors. The aim of this work was to synthesise thick bulk ingots of manganese antimonide crystalsand films with a thickness of ~ 400 nm on sitall and silicon substrates. MnSb crystals were synthesised using the vacuum-ampoule method and identified using XRD, DTA, and microstructural analysis. The results of studies of bulk samples indicated the presence of an insignificant amount of antimony in additionto the MnSb phase. According to the DTA thermogram of the MnSb alloy, a small endothermic effect was observed at 572 °C, which corresponds to the melting of the eutectic on the part of antimony in the Mn-Sb system. Such composition, according to previous studies, guaranteed the production of manganese antimonide with the maximum Curie temperature. A study of the magnetic properties showed that the synthesised MnSb crystals were a soft ferromagnet with the Curie point ~ 587 K. Thin MnSb films were obtained by an original method using separate sequential deposition in a high vacuum of the Mnand Sb metals with their subsequent annealing. To optimise the process of obtaining films with stoichiometric composition, the dependences of the thickness of metal films on the parameters of the deposition process were calculated. The temperature range of annealing at which the metals interact with the formation of ferromagnetic MnSb films was established, the films were identified, and their electrical and magnetic properties were measured
16
Kawasaki, Haruhisa. "Special Issue on Mechatronics." Journal of Robotics and Mechatronics 3, no. 4 (1991): 301. http://dx.doi.org/10.20965/jrm.1991.p0301.
Full textAbstract:
Mechatronics is a term created to represent the total technology of mechanisms and electronics. Mechanical engineering dealing with mechanisms has a very long history. Its recent organic combination with electronics has certainly brought about a striking advance in the functions and performance of machines. This striking advance lay in the background of the creation of the new term “mechatronics”. The initiation of mechatronics was no doubt due to the advent of NC machine tools. NC machine tools were accomplished by fusing mechanisms with servo unit drives and computer techniques. The technique using them was somewhat innovative in that servo units were driven by digital computer signals. Mechatronics is considered as essential to develop peripheral machines for computers such as plotters, printers and magnetic memories, and as an application to wire bonding machines and X-ray exposing machines in semiconductor manufacturing processes. For such machines, increasingly higher speed and accuracy are likely to be required, and engineering developments are actively underway accordingly. This special issue was planned to present the current status and recent trends of mechatronic research arid development in Japan. The contents can be classified into three categories. First, bearings and actuators as basic mechatronic elements are featured. For bearings, trends of research and development on magnetic types which permit ultrahigh-speed rotation and operation in vacuum in particular were chosen. For actuators, recent examples of research and development on ultrasonic motors, linear motors and piezoelectric actuators were selected. Second, this issue presents examples of development in the area of X-ray steppers, memory medium handling systems, and polygonal scanners. These are frontier mechatronic systems and the descriptions will be of some help in recognizing future problems in development. Finally, some studies from the point of view of force-torque control were selected. While conventional mechatronic control studies are primarily concerned with position and speed control, force-torque control is expected to become an important trend. I hope that this special issue will be helpful in recognizing the current situation and future trends of mechatronics, and contribute to future developments in this area.
17
KATZENELSON, JACOB, and ALEXANDER GOIKHMAN. "THE SUPERCOMPUTER TOOLKIT AND ITS APPLICATIONS." International Journal of High Speed Electronics and Systems 09, no. 03 (1998): 807–46. http://dx.doi.org/10.1142/s0129156498000336.
Full textAbstract:
The Supercomputer Toolkit is a family of hardware and software modules from which high-performance special-purpose computers for scientific/engineering use can be easily constructed and programmed. The hardware modules include processors, memory, I/O devices and communication devices. The software modules include an operating system, compilers, debuggers, simulators, scientific libraries, and high-level front ends. When faced with a suitable problem, the engineer/scientist connects the modules by means of static-interconnect technology and constructs a problem-specific parallel computation network. The network is loaded from a workstation that serves as a host. When the program is run, results are collected and displayed by the host. The host handles files, does compilation, etc. The computation network, the Toolkit, does the heavy computation. In addition to high performance, the advantage of the Toolkit is its low cost which makes it potentially affordable by small groups as their main number crunching computer. This paper is concerned with the Toolkit version built at the Technion, which is a second generation of the MIT version.1 The paper briefly describes the hardware and software of this new version and its application to elastic-plastic flow, weather prediction and the simulation of electronic circuits. The main topic of the application section is the relation between the Toolkit configuration and the computation structure of these applications. The paper discusses conclusions related to the hardware and software as well as to the techniques for applying the system.
18
Renaut, Rosemary A., Jarom D. Hogue, Saeed Vatankhah, and Shuang Liu. "A fast methodology for large-scale focusing inversion of gravity and magnetic data using the structured model matrix and the 2-D fast Fourier transform." Geophysical Journal International 223, no. 2 (2020): 1378–97. http://dx.doi.org/10.1093/gji/ggaa372.
Full textAbstract:
SUMMARY We discuss the focusing inversion of potential field data for the recovery of sparse subsurface structures from surface measurement data on a uniform grid. For the uniform grid, the model sensitivity matrices have a block Toeplitz Toeplitz block structure for each block of columns related to a fixed depth layer of the subsurface. Then, all forward operations with the sensitivity matrix, or its transpose, are performed using the 2-D fast Fourier transform. Simulations are provided to show that the implementation of the focusing inversion algorithm using the fast Fourier transform is efficient, and that the algorithm can be realized on standard desktop computers with sufficient memory for storage of volumes up to size n ≈ 106. The linear systems of equations arising in the focusing inversion algorithm are solved using either Golub–Kahan bidiagonalization or randomized singular value decomposition algorithms. These two algorithms are contrasted for their efficiency when used to solve large-scale problems with respect to the sizes of the projected subspaces adopted for the solutions of the linear systems. The results confirm earlier studies that the randomized algorithms are to be preferred for the inversion of gravity data, and for data sets of size m it is sufficient to use projected spaces of size approximately m/8. For the inversion of magnetic data sets, we show that it is more efficient to use the Golub–Kahan bidiagonalization, and that it is again sufficient to use projected spaces of size approximately m/8. Simulations support the presented conclusions and are verified for the inversion of a magnetic data set obtained over the Wuskwatim Lake region in Manitoba, Canada.
19
T S, Chandrakantha, Basavaraj N. Jagadale, Abhisheka T E, and Omar Abdullah Murshed Farhan Alnaggar. "Automated Identification and Localization of Brain Tumor in MRI Using U-Net Segmentation and CNN-LSTM Classification." International Journal on Recent and Innovation Trends in Computing and Communication 11, no. 10s (2023): 637–44. http://dx.doi.org/10.17762/ijritcc.v11i10s.7703.
Full textAbstract:
Nowadays, the use of computers to evaluate medical images automatically is critical part of the life. Today's treatment method relies heavily on early diagnosis and accurate disease identification, which were formerly difficult for medical research to achieve. Brain Magnetic Resonance Imaging (MRI) is essential to the detection and treatment of brain tumor (BT). Tumor of the brain are the result of brain cell division that has gone awry or is otherwise out of control. The manual MRI segmentation of BT is a difficult and time-consuming process. The most critical factor in the effective treatment and identification of BT is the ability to accurately locate the tumor. The detection of BT is regarded as a difficult task in medical image processing. For analysing and interpreting MRI, there are semi-automatic and fully automated systems that require large-scale professional input and evaluation, with varying degrees of effectiveness. Automated identification and extraction of the tumor's localization from brain MRI will be proposed in this paper. To achieve this goal, the data collected from Kaggle and the collected data are processed. Then the U-Net is employed to segment the tumor region from the MRI. Next, the MRI is classified using DL models like Convolutional Neural Network (CNN), and the hybrid Convolutional Neural Network and Long Short-Term Memory (CNN-LSTM). Both process segmentation and classification are evaluated using the metrics. From the evaluation, it is identified that CNN-LSTM outperforms the CNN model.
20
Zheng, Qiu Ju. "Analysis of New Materials of Computer Memory." Applied Mechanics and Materials 416-417 (September 2013): 1657–60. http://dx.doi.org/10.4028/www.scientific.net/amm.416-417.1657.
Full textAbstract:
Modern computer memory, in addition to cache memory, is mainly divided into two categories: internal memory and external memory. External memory mainly comprises of magnetic or optical disks, floppy disks, tapes, like hard disks, CDs, which can store information, and do not depend on electricity to save information. In the new technology, the computer memory materials are facing a revolution of industry upgrade. In this paper, based on a lot of information the author makes a brief analysis of the new material of the external memory, that is, the phase change storage materials, titanium oxide crystals form materials, magnetic materials and organic ferroelectric materials, and comprehensively promote the new research and new development of computer storage materials.
21
Guo, Feng Ying. "The Hardware Design and Implement of an Image Information Collection System." Advanced Materials Research 804 (September 2013): 211–15. http://dx.doi.org/10.4028/www.scientific.net/amr.804.211.
Full textAbstract:
It introduces the hardware design and implement of the image information collection system which is one part of Fluorescent magnetic particle nondestructive detection system of Cannonball. The image information collection system includes Open collecting card model Initialize collection card modelApply for EMS memory modelCollecting image modelWrite bitmap information head model Show pictures modeClose collection card model. Through collecting image information to the EMS memory and then processing the image information, the magnetic images on the cannonball are showed clearly on computer, and cracks on the cannonball can easily to be judged. The software of the image information collection system is developed by Visual C++.
22
JIAN, Xingliang. "Magnetic Memory Experiment Based on Magnetic Gradient Measurement." Journal of Mechanical Engineering 46, no. 04 (2010): 15. http://dx.doi.org/10.3901/jme.2010.04.015.
Full text
23
Stankevič, Voitech, Skirmantas Keršulis, Justas Dilys, et al. "Measurement System for Short-Pulsed Magnetic Fields." Sensors 23, no. 3 (2023): 1435. http://dx.doi.org/10.3390/s23031435.
Full textAbstract:
A measurement system based on the colossal magnetoresistance CMR-B-scalar sensor was developed for the measurement of short-duration high-amplitude magnetic fields. The system consists of a magnetic field sensor made from thin nanostructured manganite film with minimized memory effect, and a magnetic field recording module. The memory effect of the La1−xSrx(Mn1−yCoy)zO3 manganite films doped with different amounts of Co and Mn was investigated by measuring the magnetoresistance (MR) and resistance relaxation in pulsed magnetic fields up to 20 T in the temperature range of 80–365 K. It was found that for low-temperature applications, films doped with Co (LSMCO) are preferable due to the minimized magnetic memory effect at these temperatures, compared with LSMO films without Co. For applications at temperatures higher than room temperature, nanostructured manganite LSMO films with increased Mn content above the stoichiometric level have to be used. These films do not exhibit magnetic memory effects and have higher MR values. To avoid parasitic signal due to electromotive forces appearing in the transmission line of the sensor during measurement of short-pulsed magnetic fields, a bipolar-pulsed voltage supply for the sensor was used. For signal recording, a measurement module consisting of a pulsed voltage generator with a frequency up to 12.5 MHz, a 16-bit ADC with a sampling rate of 25 MHz, and a microprocessor was proposed. The circuit of the measurement module was shielded against low- and high-frequency electromagnetic noise, and the recorded signal was transmitted to a personal computer using a fiber optic link. The system was tested using magnetic field generators, generating magnetic fields with pulse durations ranging from 3 to 20 μs. The developed magnetic field measurement system can be used for the measurement of high-pulsed magnetic fields with pulse durations in the order of microseconds in different fields of science and industry.
24
Prokaznikov, A. V., V. A. Paporkov, V. A. Chirikov, and N. A. Evseeva. "Patterns of the Formation of Mobile Localized Magnetic Configurations and Technology for Manufacturing Structures for the Implementation of Magnetic Memory Elements." Микроэлектроника 52, no. 5 (2023): 390–403. http://dx.doi.org/10.31857/s0544126923700485.
Full textAbstract:
Based on computer simulation and the analysis of technological, experimental, and theoretical results, the technological requirements for the formation of electronic devices based on magnetic vortices and skyrmions are formulated. The main types of interactions determined by technological factors are deter-mined. The design features of electronic devices based on magnetic vortices and skyrmions are studied. Various technological approaches to the fabrication of structures with different magnetic anisotropy properties are studied.
25
Cartlidge, Edwin. "A Photonic Upgrade for Computer Memory?" Optics and Photonics News 27, no. 4 (2016): 24. http://dx.doi.org/10.1364/opn.27.4.000024.
Full text
26
Brewer, L. N., and V. P. Dravid. "Magnetic Contrast in the cFEG SEM Using the Upper (Above-the-Lens) Detector." Microscopy and Microanalysis 3, S2 (1997): 523–24. http://dx.doi.org/10.1017/s1431927600009508.
Full textAbstract:
An unconventional and important use of the SEM is in the study of magnetic phenomena of materials. Many magnetic phenomena occur on the surfaces of materials as is the case for magnetic recording in computer memory and audio tapes. The “above-the-lens” or “upper” detector of the cFEG SEM(Hitachi S4500) is especially suited to probing surface phenomena (Fig. 1). The upper detector is used in combination with a magnetic “snorkel” lens which pulls secondary electrons (SE) up to the detector, resulting in an extremely high and pure SE yield. While magnetic imaging in a standard, side-mounted Everhart-Thornley (lower) detector is well understood, the image contrast mechanism for the upper detector is not presently known. We tested both energy filtering and trajectory contrast as possible magnetic contrast mechanisms using a cassette recording tape (Fe2O3 based) and barium hexaferrite ceramic magnets.Two sets of experiments were performed to explore the magnetic contrast.
27
Noyes, T., and W. E. Dickinson. "The Random-Access Memory Accounting Machine II. The magnetic-disk, random-access memory." IBM Journal of Research and Development 44, no. 1.2 (2000): 16–19. http://dx.doi.org/10.1147/rd.441.0016.
Full text
28
Zhang, Li, Hualian Tang, Beilei Xu, Yiqi Zhuang, and Junlin Bao. "A High Reliability Sense Amplifier for Computing In-Memory with STT-MRAM." SPIN 10, no. 02 (2020): 2040001. http://dx.doi.org/10.1142/s2010324720400019.
Full textAbstract:
In the era of big data, massive data requires processing efficiently. However, the limited data bandwidth between the memory and the processor in conventional computer systems could not meet the requirement of data transferring. Computing in-memory has been considered an effective solution to address this problem. In this paper, based on the spin transfer torque-magnetic random access memory (STT-MRAM), a computing in-memory architecture with as few peripheral circuits as possible is proposed. This computing in-memory architecture gives the specific reference cell so that two rows in one array can be activated simultaneously to perform bitwise logic operations, such as OR/NOR and AND/NAND. In addition, with technology scaling down, STT-MRAM suffers from high sensitivity to process variation, which results in more device mismatch in a sense circuit. Additionally, the negative bias temperature instability (NBTI) seriously affects the life of PMOS transistors used in a sense circuit. In this paper, a high-reliability sense amplifier for computing in-memory with STT-MRAM is proposed. By using two self-enabled switching transistors, the proposed sense amplifier not only can decrease the NBTI effect on PMOS transistors but also can achieve a low sensing error rate. Using a CMOS 40[Formula: see text]nm design-kit and an accurate compact model of the STT magnetic tunnel junction (MTJ), mixed transient and statistical simulations have been present to demonstrate the functionality and performance of the proposed circuits.
29
Soler, Santiago R., and Leonardo Uieda. "Gradient-boosted equivalent sources." Geophysical Journal International 227, no. 3 (2021): 1768–83. http://dx.doi.org/10.1093/gji/ggab297.
Full textAbstract:
SUMMARY The equivalent source technique is a powerful and widely used method for processing gravity and magnetic data. Nevertheless, its major drawback is the large computational cost in terms of processing time and computer memory. We present two techniques for reducing the computational cost of equivalent source processing: block-averaging source locations and the gradient-boosted equivalent source algorithm. Through block-averaging, we reduce the number of source coefficients that must be estimated while retaining the minimum desired resolution in the final processed data. With the gradient-boosting method, we estimate the sources coefficients in small batches along overlapping windows, allowing us to reduce the computer memory requirements arbitrarily to conform to the constraints of the available hardware. We show that the combination of block-averaging and gradient-boosted equivalent sources is capable of producing accurate interpolations through tests against synthetic data. Moreover, we demonstrate the feasibility of our method by gridding a gravity data set covering Australia with over 1.7 million observations using a modest personal computer.
30
He, Yingming, Qilong Xue, Weiguo Hai, Xuesong Xing, Xudong Wu, and Xing Fu. "Experimental Study on Fatigue Damage of Drilling Tool Materials Based on Magnetic Memory Detection." Machines 11, no. 7 (2023): 701. http://dx.doi.org/10.3390/machines11070701.
Full textAbstract:
In drilling engineering, the cost of drilling tool fracture is enormous, and studying the fatigue failure process of drilling tools has practical significance. This paper uses metal magnetic memory detection technology to design and conduct fatigue damage tests on typical drilling tool material 42CrMo specimens under tensile, torsional, compressive, tensile, compressive, and torsional dynamic loading conditions. By analyzing the changes in the tangential component Hp(x) and gradient value K of the magnetic memory signal under different load conditions with the number of loading times, the process of fatigue failure of the specimens and the trend of changes in the magnetic memory signal in local stress concentration areas are explored. The characteristic parameters of fatigue damage based on magnetic memory detection were extracted and the critical point at which fatigue damage leads to crack initiation was inferred. This confirms that metal magnetic memory testing technology is an effective means of analyzing the fatigue damage process of drilling tools and provides a certain reference for formulating judgment standards for drilling tool maintenance on site.
31
Hayama, Hiroki R., Kristin M. Drumheller, Mark Mastromonaco, Christopher Reist, Lawrence F. Cahill, and Michael T. Alkire. "Event-related Functional Magnetic Resonance Imaging of a Low Dose of Dexmedetomidine that Impairs Long-term Memory." Anesthesiology 117, no. 5 (2012): 981–95. http://dx.doi.org/10.1097/aln.0b013e31826be467.
Full textAbstract:
Abstract Background Work suggests the amnesia from dexmedetomidine (an α2-adrenergic agonist) is caused by a failure of information to be encoded into long-term memory and that dexmedetomidine might differentially affect memory for emotionally arousing material. We investigated these issues in humans using event-related neuroimaging to reveal alterations in brain activity and subsequent memory effects associated with drug exposure. Methods Forty-eight healthy volunteers received a computer-controlled infusion of either placebo or low-dose dexmedetomidine (target = 0.15 ng/ml plasma) during neuroimaging while they viewed and rated 80 emotionally arousing (e.g., graphic war wound) and 80 nonarousing neutral (e.g., cup) pictures for emotional arousal content. Long-term picture memory was tested 4 days later without neuroimaging. Imaging data were analyzed for drug effects, emotional processing differences, and memory-related changes with statistical parametric mapping-8. Results Dexmedetomidine impaired overall (mean ± SEM) picture memory (placebo: 0.58 ± 0.03 vs. dexmedetomidine: 0.45 ± 0.03, P = 0.001), but did not differentially modulate memory as a function of item arousal. Arousing pictures were better remembered for both groups. Dexmedetomidine had regionally heterogeneous effects on brain activity, primarily decreasing it in the cortex and increasing it in thalamic and posterior hippocampal regions. Nevertheless, a single subsequent memory effect for item memory common to both groups was identified only in the left hippocampus/amygdala. Much of this effect was found to be larger for the placebo than dexmedetomidine group. Conclusion Dexmedetomidine impaired long-term picture memory, but did not disproportionately block memory for emotionally arousing items. The memory impairment on dexmedetomidine corresponds with a weakened hippocampal subsequent memory effect.
32
SR, SHARUNYA, VIJAYALAKSHMI DESAI, MEENAKSHI SINGH, and KUSUMA M. "Survey on Early Detection of Alzhiemer’s Disease Using Capsule Neural Network." International Journal of Artificial Intelligence 7, no. 1 (2020): 7–12. http://dx.doi.org/10.36079/lamintang.ijai-0701.65.
Full textAbstract:
Alzheimer's disease (AD) is an disorder which is irreversible of the brain related to memory loss, mostly found in the old and aged population. Alzheimer's dementia results from the degeneration or loss of brain cells. The brain-imaging technologies most often used to diagnose AD is Magnetic resonance imaging (MRI). MRI or structural magnetic resonance is a very popular and actual technique used to diagnose AD. An MRI uses magnets and powerful radio waves to create a complete view of your brain. To actually detect the presence of Alzheimer’s, the MRI should me studied carefullyImplementation of CBIR Content Based Image Retrival which is a revolutionary computer aided diagnosis technique will create new abilities in MRI Magnetic resonance imaging in related image retrieval and training for recognition of development of AD in early stages
33
Li, Hai Xia, Hai Long Yu, and Ping Chuan Zhang. "Application of 3D Apparent Physical Properties Inversion Method in an Iron Mine Area." Advanced Materials Research 734-737 (August 2013): 37–40. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.37.
Full textAbstract:
A rapid method for 3D physical properties inversion based on separation and continuation of potential field are introduced in this paper. The inversion technique characterized by faster computing speed, it does not need to divide the underground field sources region into many rectangular blocks in one time and does not need to solve linear algebraic equations as well. So, this technique can overcome the requirement of large computer memory, unstable solution and computation time bottleneck which hinders the application of 3D inversion to practice. The method is used to apparent magnetic susceptibility inversion of magnetic anomaly in a iron mine area, the inversion results show that the method has good accuracy, and the advantages of strong stability and a high computation speed, and is suitable for 3D inversion of magnetic data in large area.
34
Zhang, Honghong, and Guoguo Zhang. "Review of Research on Storage Development." Scalable Computing: Practice and Experience 22, no. 3 (2021): 365–85. http://dx.doi.org/10.12694/scpe.v22i3.1904.
Full textAbstract:
The development of computer external storage has undergone the continuous change of perforated cassettes, tapes, floppy disks, hard disks, optical disks and flash disks. Internal memory has gone through the development of drum storage, Williams tube, mercury delay line, and magnetic core storage, until the emergence of semiconductor memory. Later RAM and ROM were born. RAM was divided into DRAM and SRAM. Due to its structure and cost advantages, DRAM has gradually developed into the widely used DDR series. At the same time, the low-power LPDDR series has also been advancing. At present, with the development of NVRAM technology, non-volatile random access memory with both internal and external storage functions is born. Dual-space storage based on NVRAM combines internal and external storage into one, and large capacity dual-space storage has become the development trend of storage.
35
Hu, J. M., L. Shu, Z. Li, et al. "Film size-dependent voltage-modulated magnetism in multiferroic heterostructures." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2009 (2014): 20120444. http://dx.doi.org/10.1098/rsta.2012.0444.
Full textAbstract:
The electric-voltage-modulated magnetism in multiferroic heterostructures, also known as the converse magnetoelectric (ME) coupling, has drawn increasing research interest recently owing to its great potential applications in future low-power, high-speed electronic and/or spintronic devices, such as magnetic memory and computer logic. In this article, based on combined theoretical analysis and experimental demonstration, we investigate the film size dependence of such converse ME coupling in multiferroic magnetic/ferroelectric heterostructures, as well as exploring the interaction between two relating coupling mechanisms that are the interfacial strain and possibly the charge effects. We also briefly discuss some issues for the next step and describe new device prototypes that can be enabled by this technology.
36
Benenson, M. Z., and A. P. Divin. "FUNCTIONAL TESTS FOR MULTIPROCESSOR COMPUTER SYSTEMS." Issues of radio electronics, no. 5 (May 20, 2018): 111–19. http://dx.doi.org/10.21778/2218-5453-2018-5-111-119.
Full textAbstract:
The article covers the technique of construction of a subsystem functional tests designed to check the configuration of the instrument and measure the performance of a multiprocessor computing system (platform). Algorithms for determining the configuration of the system and measure the performance of processors in heterogeneous computing system. For interaction between the processors was chosen as the most common parallel programming interface standard for data exchange MPI. Performance measurement was carried out using a known test sets Intel - MPI Benchmark and HPL LINPACK, which allow to fully assess the bandwidth of communication network and the performance of the modules of Central processor computing platform. Received graphs of throughput and performance. The methods of measuring the speed exchange with memory and storage on magnetic disks. To measure the performance of graphics processors proposed an original methodology based on the parallelization of computing across multiple processors Given the overall estimation of maximum performance heterogeneous computing system. The obtained results confirm the effectiveness of the proposed methods to verify the claimed functionality of multiprocessor computing systems.
37
Pandu Rangan, C., and N. Meenakshi. "Matrix transposition in a magnetic bubble memory." International Journal of Computer Mathematics 26, no. 1 (1988): 11–27. http://dx.doi.org/10.1080/00207168808803680.
Full text
38
Yang, C. P., S. H. Lin, M. L. Hsieh, K. Y. Hsu, and T. C. Hsieh. "A Holographic Memory for Digital Data Storage." International Journal of High Speed Electronics and Systems 08, no. 04 (1997): 749–65. http://dx.doi.org/10.1142/s0129156497000317.
Full textAbstract:
A read-only holographic memory for digital data storage is experimentally demonstrated. Techniques for coding and decoding of optical signals, and the interface techniques between the optical memory and a personal computer are described. The performance of the optical memory and the techniques for improving the bit error rate (BER) are presented.
39
HASUO, SHINYA. "JOSEPHSON DEVICES FOR COMPUTER APPLICATIONS." International Journal of High Speed Electronics and Systems 03, no. 01 (1992): 13–52. http://dx.doi.org/10.1142/s0129156492000035.
Full textAbstract:
Josephson integrated circuit technology has progressed remarkably since the introduction of the reliable niobium junction. Josephson microprocessors and memory circuits that were once considered impracticable have been demonstrated. All the functions required for a Josephson computer can now be fabricated, although integration densities are still much lower than those achievable with semiconductor devices. The next step is to demonstrate a small-scale special-purpose Josephson computer system.
40
Yi, Hong. "Recent Progress on Waveguide-Based Phase-Change Photonic Storage Memory." Journal of Nanoelectronics and Optoelectronics 17, no. 2 (2022): 187–94. http://dx.doi.org/10.1166/jno.2022.3194.
Full textAbstract:
Memory targeted for data storage plays a key role in determining the operational performances of the modern digital computer, particularly in the age of ‘big data.’ Conventional computer memory devices are usually made of complementary-metal-oxide-semiconductors (CMOS). Along with the increase of the integration density, the distance between neighboring CMOS components is further reduced, consequently accompanied with some adverse effects such as relatively low transmission speed and severe disturbances. To address these issues, an innovative photonic memory that combines phase-change materials with silicon-based waveguides has recently attained tremendous attention owing to its ability to store and process data in a photonic manner. Triggered by this novel concept, a plasmonic-based phase-change integrated memory was subsequently proposed, which allows for similar properties to the waveguide-based memory but with higher integration density. In spite of these progress, a comprehensive review related to the operational principle of these emerging memories, their current status, and the prospect envisage is still missing. To help researchers better understand the performances superiorities of the phase-change photonic memory, in this review we first present the physical properties of the phase-change materials, and subsequently introduce the operational principles of different phase-change photonic memories such as waveguide-based memory and plasmonic-based memory. The current status of these memories is also elaborated, followed by the detailed analysis of their respective performance pros and cons. The developing prospect of the phase-change photonic memories are finally envisaged.
41
Duangthong, Chatuporn, Pornchai Supnithi, and Watid Phakphisut. "Two-Dimensional Error Correction Code for Spin-Transfer Torque Magnetic Random-Access Memory (STT-MRAM) Caches." ECTI Transactions on Computer and Information Technology (ECTI-CIT) 16, no. 3 (2022): 237–46. http://dx.doi.org/10.37936/ecti-cit.2022163.246903.
Full textAbstract:
Spin-Transfer Torque Magnetic Random-Access Memory (STT-MRAM) is an emerging nonvolatile memory (NVM) technology that can replace conventional cache memory in computer systems. STT-RAM has many desirable properties such as high writing and reading speed, non-volatility, and low power consumption. Since the cache requires a high speed of writing and reading speed, a single-error correction and double error detection (SEC - DED) are applicable to improve the reliability of the cache. However, the process variation and thermal fluctuation of STT-MRAM cause errors. For example, writing ‘1’ bits has more errors than writing ‘0’ bits. We then design the weight reduction code to reduce the error caused by writing ‘1’ bits. Moreover, the performance of an SEC-DED code is improved by constructing an SED-DED code as the product code. The simulation results demonstrate that the two-dimensional error correction code consisting of product code and weight reduction code is roughly 5.67 × 10−4 lower than the SEC-DED code when the error rate of writing ‘1’ bits is equal to 6 × 10−3.
42
Stevens, John K., and Judy Trogadis. "The application of 3D volume investigation methods to serial confocal and serial EM data: Distribution of microtubules in PC12 cells." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 146–47. http://dx.doi.org/10.1017/s0424820100085034.
Full textAbstract:
CAD or Computer Assisted Design uses a computer workstation to create or design new objects. Volume Investigation (VI) uses a computer workstation to understand or analyze existing objects. CAD systems are used to produce a mathematical model of a new object, stored in the workstation's memory. This model is created interactively by the user of the workstation. In contrast, VI systems synthesize a similar mathematical-model automatically from an existing object. The model is usually created or “reconstructed” from a stack of serial cross-sections of the original object. These cross-sections may be collected non-destructively from computerized tomography scans (CT), magnetic resonance imaging scans (MRI), confocal microscopy or destructively from serial light microscopy, serial electron microscopy, or any other source of serial sections. VI workstations are in widespread use in clinical settings, but have not been used at all in scientific research.
43
Narayan, P. B. "Ultramicrotomy in the Analysis of Magnetic Recording Media." Proceedings, annual meeting, Electron Microscopy Society of America 43 (August 1985): 212–13. http://dx.doi.org/10.1017/s0424820100117984.
Full textAbstract:
Particulate magnetic recording media is widely used to store information in computer memory applications. The media consists of submicron-size gamma iron oxide and alumina particles held together by a binder resin onto a substrate (mylar for floppy disks and aluminum for rigid disks). The electrical properties of media depend on the physical characteristics (like size and shape), dispersion and orientation of iron oxide. Well- dispersed and optimum-sized alumina improvies wear resistance of the relatively soft media. Transmission electron microscopy (TEM), with its excellent spatial resolution, is found to be very useful in analyzing media. Ultramicrotomy can be conveniently used to prepare cross-sections of the media for TEM study The major advantage of ultramicrotomy is that it provides a large amount of uniformly thin area relatively quickly.
44
Gao, Fumin, JianChun Fan, Laibin Zhang, Jiankang Jiang, and Shoujie He. "Magnetic crawler climbing detection robot basing on metal magnetic memory testing technology." Robotics and Autonomous Systems 125 (March 2020): 103439. http://dx.doi.org/10.1016/j.robot.2020.103439.
Full text
45
Pirge, G., C. V. Hyatt, and S. Altıntaş. "Characterization of NiMnGa magnetic shape memory alloys." Journal of Materials Processing Technology 155-156 (November 2004): 1266–72. http://dx.doi.org/10.1016/j.jmatprotec.2004.04.225.
Full text
46
Palai, G., B. Nayak, Santosh Kumar Sahoo, Soumya Ranjan Nayak, and S. K. Tripathy. "Metamaterial based photonic crystal fiber memory for optical computer." Optik 171 (October 2018): 393–96. http://dx.doi.org/10.1016/j.ijleo.2018.06.083.
Full text
47
Nebashi, Ryusuke, Noboru Sakimura, and Tadahiko Sugibayashi. "Soft-error tolerance and energy consumption evaluation of embedded computer with magnetic random access memory in practical systems using computer simulations." Japanese Journal of Applied Physics 56, no. 8 (2017): 0802B6. http://dx.doi.org/10.7567/jjap.56.0802b6.
Full text
48
Liu, Shuaishuai, Handong Tan, Miao Peng, and Yanxing Li. "Three-Dimensional Limited-Memory BFGS Inversion of Magnetic Data Based on a Multiplicative Objective Function." Applied Sciences 13, no. 20 (2023): 11198. http://dx.doi.org/10.3390/app132011198.
Full textAbstract:
At present, the traditional magnetic three-dimensional inversion method has been fully developed and is widely used. Magnetic exploration is a kind of geophysical exploration method that uses the magnetic field changes (magnetic anomalies) caused by the magnetic differences between various rocks in the crust to find useful mineral resources and study the underground structure. Traditional magnetic three-dimensional inversion is relatively inefficient. Moreover, the traditional additive objective function (data fitting difference term plus regularization term and logarithmic obstacle term), which causes the regularization factor selection to be more complicated, is implemented in this method. Therefore, it is necessary to establish a new efficient three-dimensional magnetic inversion algorithm and optimize the selection of regularization factors. In this paper, based on the limited-memory BFGS (L-BFGS) method, the three-dimensional magnetic inversion of a multiplicative objective function is realized. The inversion test is conducted in this paper using both theoretical synthesis data and measured data. The results demonstrate that the limited-memory BFGS method significantly enhances the inversion efficiency and yields superior inversion outcomes compared to traditional magnetic three-dimensional inversion methods. Additionally, the multiplicative objective function-based three-dimensional magnetic inversion method simplifies the process of selecting weight factors for regularization terms.
49
Gulafshan, Gulafshan, Selma Amara, Rajat Kumar, Danial Khan, Hossein Fariborzi, and Yehia Massoud. "Bitwise Logical Operations in VCMA-MRAM." Electronics 11, no. 18 (2022): 2805. http://dx.doi.org/10.3390/electronics11182805.
Full textAbstract:
Today’s technology demands compact, portable, fast, and energy-efficient devices. One approach to making energy-efficient devices is an in-memory computation that addresses the memory bottleneck issues of the present computing system by utilizing a spintronic device viz. magnetic tunnel junction (MTJ). Further, area and energy can be reduced through approximate computation. We present a circuit design based on the logic-in-memory computing paradigm on voltage-controlled magnetic anisotropy magnetoresistive random access memory (VCMA-MRAM). During the computation, multiple bit cells within the memory array are selected that are in parallel by activating multiple word lines. The designed circuit performs all logic operations-Read/NOT, AND/NAND, OR/NOR, and arithmetic SUM operation (1-bit approximate adder with 75% accuracy for SUM and accurate carry out) by slight modification using control signals. All the simulations have been performed at a 45 nm CMOS technology node with VCMA-MTJ compact model by using the HSPICE simulator. Simulation results show that the proposed circuit’s approximate adder consumes about 300% less energy and 2.3 times faster than its counterpart exact adder.
50
SANO, T., F. NAITO, S. YOSHIDA, and M. YAMAMOTO. "Computer Simulation Analysis of Speckle-Shift Multiplexed Recording in Holographic Memory." IEICE Transactions on Electronics E90-C, no. 8 (2007): 1606–11. http://dx.doi.org/10.1093/ietele/e90-c.8.1606.
Full text