Using rank hashing function to develop a data allocating scheme for a two-disk system

Blockchain is widely used in encrypted currency, Internet of Things (IoT), supply chain finance, data sharing, and other fields. However, there are security problems in blockchains to varying degrees. As an important component of blockchain, hash function has relatively low computational efficiency. Therefore, this paper proposes a new scheme to optimize the blockchain hashing algorithm based on PRCA (Proactive Reconfigurable Computing Architecture). In order to improve the calculation performance of hashing function, the paper realizes the pipeline hashing algorithm and optimizes the efficiency of communication facilities and network data transmission by combining blockchains with mimic computers. Meanwhile, to ensure the security of data information, this paper chooses lightweight hashing algorithm to do multiple hashing and transforms the hash algorithm structure as well. The experimental results show that the scheme given in the paper not only improves the security of blockchains but also improves the efficiency of data processing.

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A FAST CHINESE CHARACTERS ACCESSING TECHNIQUE USING MANDARIN PHONETIC TRANSCRIPTIONS

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001488000091 ◽

1988 ◽

Vol 02 (01) ◽

pp. 105-137 ◽

Cited By ~ 1

Author(s):

C.C. CHANG ◽

H.C. WU

Keyword(s):

Main Idea ◽

Chinese Characters ◽

One To One ◽

Hashing Function ◽

Perfect Hashing ◽

The Way

In this paper, we consider the problem of how to design a minimal perfect hashing function which is suitable for the Mandarin Phonetic Symbols system. Our main idea is inspired by Chang’s letter-oriented minimal perfect hashing scheme. By using our hashing function, 1303 Mandarin phonetic symbol transcriptions will be hashed to 1303 locations in the way of one-to-one correspondence.

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Disk Position Nonlinearity Effects on the Chaotic Behavior of Rotating Flexible Shaft-Disk Systems

Journal of Mechanics ◽

10.1017/jmech.2012.61 ◽

2012 ◽

Vol 28 (3) ◽

pp. 513-522 ◽

Cited By ~ 2

Author(s):

H. M. Khanlo ◽

M. Ghayour ◽

S. Ziaei-Rad

Keyword(s):

Partial Differential Equations ◽

Differential Equations ◽

Dynamic Behavior ◽

Chaotic Behavior ◽

Equations Of Motion ◽

Beam Theory ◽

Disk System ◽

Partial Differential ◽

Rayleigh Beam ◽

Flexible Shaft

AbstractThis study investigates the effects of disk position nonlinearities on the nonlinear dynamic behavior of a rotating flexible shaft-disk system. Displacement of the disk on the shaft causes certain nonlinear terms which appears in the equations of motion, which can in turn affect the dynamic behavior of the system. The system is modeled as a continuous shaft with a rigid disk in different locations. Also, the disk gyroscopic moment is considered. The partial differential equations of motion are extracted under the Rayleigh beam theory. The assumed modes method is used to discretize partial differential equations and the resulting equations are solved via numerical methods. The analytical methods used in this work are inclusive of time series, phase plane portrait, power spectrum, Poincaré map, bifurcation diagrams, and Lyapunov exponents. The effect of disk nonlinearities is studied for some disk positions. The results confirm that when the disk is located at mid-span of the shaft, only the regular motion (period one) is observed. However, periodic, sub-harmonic, quasi-periodic, and chaotic states can be observed for situations in which the disk is located at places other than the middle of the shaft. The results show nonlinear effects are negligible in some cases.

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Effect of Molecular Weight on Lubricant Depletion in a Heat Assisted Magnetic Recording System

ASME 2017 Conference on Information Storage and Processing Systems ◽

10.1115/isps2017-5462 ◽

2017 ◽

Author(s):

Deng Pan ◽

Wenping Song

Keyword(s):

Molecular Dynamics ◽

Molecular Weight ◽

Molecular Dynamics Simulation ◽

Magnetic Recording ◽

Recording System ◽

Dynamics Simulation ◽

Disk System ◽

Heat Assisted Magnetic Recording ◽

Lubricant Depletion

A model for studying lubricant depletion in HAMR slider/disk system was developed based on molecular dynamics simulation. We found that the lubricant molecular weight has small effect on lubricant depletion.

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Additional Investigations Into the Natural Frequencies and Critical Speeds of a Rotating, Flexible Shaft-Disk System

Volume 5: Turbo Expo 2007 ◽

10.1115/gt2007-28065 ◽

2007 ◽

Cited By ~ 3

Author(s):

Lyn M. Greenhill ◽

Valerie J. Lease

Keyword(s):

Natural Frequencies ◽

Slenderness Ratio ◽

Rotor Dynamics ◽

Axial Position ◽

Disk System ◽

Apparent Contradiction ◽

Critical Speeds ◽

Shaft Flexibility ◽

Gyroscopic Effects ◽

Lumped Masses

Traditional rotor dynamics analysis programs make the assumption that disk components are rigid and can be treated as lumped masses. Several researchers have studied this assumption with specific analytical treatments designed to simulate disk flexibility. The general conclusions reached by these studies indicated disk flexibility has little effect on critical speeds but significantly influences natural frequencies. This apparent contradiction has been reexamined by using axisymmetric harmonic finite elements to directly represent both disk and shaft flexibility along with gyroscopic effects. Results from this improved analysis show that depending on the thickness-to-diameter (slenderness) ratio of the disk and the axial position of the disk on the shaft, there are significant differences in all natural frequencies, for both forward and backward modes, including synchronous crossings at critical speeds.

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Statistical Properties of Kerr BH Flywheel Model of QSOs/AGNs

Symposium - International Astronomical Union ◽

10.1017/s0074180900163351 ◽

2000 ◽

Vol 195 ◽

pp. 417-418

Author(s):

S. Nitta

Keyword(s):

Black Holes ◽

Black Hole ◽

Kerr Black Hole ◽

Mass Function ◽

Initial Mass Function ◽

Number Density ◽

Disk System ◽

The Press ◽

The Individual ◽

Density Population

The aim of this work is to demonstrate the properties of the magnetospheric model around Kerr black holes, so-called the “flywheel” (rotation powered) model. The fly-wheel engine of the BH accretion disk system is applied to the statistics of QSOs/AGNs. Nitta, Takahashi, & Tomimatsu clarified the individual evolution of the Kerr black-hole fly-wheel engine, which is parameterized by black-hole mass, initial Kerr parameter, magnetic field near the horizon, and a dimensionless small parameter. We impose a statistical model for the initial mass function of an ensemble of black holes using the Press-Schechter formalism. With the help of additional assumptions, we can discuss the evolution of the luminosity function and the spatial number density (population) of QSOs/AGNs. The result explains well the decrease of very bright QSOs and decrease of population after z ~ 2.

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