Optimal holding time calculation algorithm to improve the reliability of high frequency bus route considering the bus capacity constraint

2021 ◽  
pp. 107632
Author(s):  
Shidong Liang ◽  
Shengxue He ◽  
Hu Zhang ◽  
Minghui Ma
Keyword(s):  
High Frequency ◽  
Capacity Constraint ◽  
Holding Time ◽  
Calculation Algorithm ◽  
Time Calculation

scholarly journals Ultraprecision Real-Time Displacements Calculation Algorithm for the Grating Interferometer System

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2409 ◽  
Author(s):  
Weinan Ye ◽  
Ming Zhang ◽  
Yu Zhu ◽  
Leijie Wang ◽  
Jinchun Hu ◽  
...  
Keyword(s):  
Real Time ◽  
Affine Transformation ◽  
Degrees Of Freedom ◽  
Diffraction Spot ◽  
Calculation Algorithm ◽  
Six Degrees Of Freedom ◽  
Time Calculation ◽  
Interference Signals ◽  
Grating Interferometer ◽  
Optical Paths

Grating interferometry is an environmentally stable displacement measurement technique that has significant potential for identifying the position of the wafer stage. A fast and precise algorithm is required for real-time calculation of six degrees-of-freedom (DOF) displacement using phase shifts of interference signals. Based on affine transformation, we analyze diffraction spot displacement and changes in the internal and external effective optical paths of the grating interferometer caused by the displacement of the wafer stage (DOWS); then, we establish a phase shift-DOWS model. To solve the DOWS in real time, we present a polynomial approximation algorithm that uses the frequency domain characteristics of nonlinearities to achieve model reduction. The presented algorithm is verified by experiment and ZEMAX simulation.

The Effect of Holding Time on the Mechanical Properties and Microstructure of Sintered NbC Composite

2010 ◽  
Vol 123-125 ◽  
pp. 803-806
Author(s):  
Duck Soo Kang ◽  
Kee Do Woo ◽  
Sang Hyuk Kim ◽  
In Jin Shon ◽  
Ji Young Kim ◽  
...  
Keyword(s):  
Grain Size ◽  
Relative Density ◽  
High Frequency ◽  
Holding Time ◽  
Full Width ◽  
Petch Relation ◽  
Sintering Time ◽  
Rapid Sintering ◽  
Sintering Method ◽  
High Frequency Induction

High frequency induction heated sintering (HFIHS) method is one of the rapid sintering methods. The advantage of rapid sintering method is that grain growth can be prevented during sintering at high temperature. Refinement of grains was known to increase the yield and flow stresses of crystals. The relation between the yield stress and the grain size is known as Hall-Petch relation. NbC-10vol.%Co, Ni and Fe composites were fabricated by HFIHS at 1060°C for 0 and 3 min as holding times under a pressure of 80MPa.The relative density of NbC-10vol.%Co, Ni and Fe composites which were sintered at 1060°C for 0min as holding time under 80MPa were 91.90%, 91.26% and 91.26%, respectively. These composites are difficult to use industrial parts due to low relative density. The longer sintering time was conducted for increasing relative density in this study. Nano-sized specimens, which were calculated grain size by full-width at half maximum (FWHM), can be obtained by HFIHS. The value of hardness and fracture toughness was investigated using 20kgf load Vickers indenter.

Rationality optimization of tool path spacing based on dwell time calculation algorithm

2015 ◽  
Vol 84 (9-12) ◽  
pp. 2055-2065 ◽  
Author(s):  
Ri Pan ◽  
Yajun Zhang ◽  
Jianbiao Ding ◽  
Cong Cao ◽  
Zhenzhong Wang ◽  
...  
Keyword(s):  
Dwell Time ◽  
Tool Path ◽  
Calculation Algorithm ◽  
Time Calculation

Modeling and Identification of Feed Drive Kinematics and Cycle Time Calculation

Manufacturing ◽  
2003 ◽  
Author(s):  
Wencai Wang ◽  
Derek M. Yip-Hoi
Keyword(s):  
Machine Tool ◽  
Cycle Time ◽  
Manufacturing Systems ◽  
Kinematic Model ◽  
Cnc Machine ◽  
Machining Processes ◽  
Calculation Algorithm ◽  
Motion Data ◽  
Feed Drive ◽  
Time Calculation

Cycle time calculation plays a major role in the design of manufacturing systems. Accurate estimates are needed to correctly determine the capacity of a line in terms of the number of machines that must be purchased. Over estimation results in excess capacity and under estimation leads to unsatisfied demand. Due to the high automation and cutting speeds of modern machining processes, cycle time calculation must consider both the timing of various machining actions and the kinematics of feed motions. This paper presents a cycle time calculation algorithm that gives accurate cycle time results by considering the effects of jerk and acceleration of the machine tool drives. The kinematic model for axis motion is based on trapezoidal acceleration profiles along the toolpaths. Based on this model, an algorithm for identifying the kinematic parameters has been developed. This algorithm has the advantage of utilizing a minimal set of axis motion data thus reducing the amount of data that must be collected from experiments by the machine tool vendor or the machine tool’s enduser. The proposed cycle time calculation algorithm has been verified in machining a V6 cylinder head on a four axis CNC machine.

An Automatic Cost Calculation System for 3-D Laser Cutting Based on Characteristic Numbers

2005 ◽  
Vol 6-8 ◽  
pp. 825-0
Author(s):  
M. Masur ◽  
F. Liébana ◽  
U. Stute
Keyword(s):  
Laser Cutting ◽  
Cost Calculation ◽  
Calculation Algorithm ◽  
Machining Time ◽  
Characteristic Numbers ◽  
Plausibility Check ◽  
Time Calculation ◽  
Cutting Velocity ◽  
Calculation System ◽  
The Cost

At present, small and medium-sized enterprises (SME) in the sheet metal industry performing 3-d laser cutting have to invest a considerable amount of time in offer preparation, although there is a low probability of obtaining the order. The offer calculation is mostly done manually and rapidly, as estimation. For example, the length of the contours to be cut are extracted from drawings and summed up. The actual production time for problem areas of the workpiece geometry like sharp angles and narrow radii can only be calculated by a post-processor simulation, or by a comparison with a similar workpiece that was manufactured before. This complicates the cost calculation and adds an unknown factor to it. Therefore, only experienced employees can estimate the costs for the cutting of 3-d workpieces. The aim of the proposed automatic cost calculation algorithm is the quick machining time calculation for 3-d laser cutting. Less experienced persons should be able to use a pre-configured tool. Characteristic numbers are generated on the basis of the workpiece geometry. They describe all necessary machine work that is required to manufacture the current workpiece. In a next step, the dynamic machine behaviour for these problem areas needs to be examined. It is projected to specific machine parameters. As example the acceleration and the maximum cutting velocity are basic parameters. By connecting the characteristic numbers with the machine parameters, the machining time for a specific machine is calculated. This machining time is an important factor for the cost calculation. The characteristic numbers can also be used to find similar workpieces within a database. This database contains existing and already evaluated offers. As a plausibility check the user can search for similar offers and compare them with the currently prepared one.

Real-Time Variance Calculation Method for Synchronous System Clock Based on Adaptive Exponential Smoothing

2014 ◽  
Vol 513-517 ◽  
pp. 1555-1560
Author(s):  
Yan Xu ◽  
Zhi Qiang Wang ◽  
Qing Yang
Keyword(s):  
Real Time ◽  
Environmental Changes ◽  
Exponential Smoothing ◽  
Calculation Algorithm ◽  
The Real ◽  
Synchronous System ◽  
System Clock ◽  
Time Calculation ◽  
Short Time ◽  
Variance Calculation

An adaptive clock variance calculation algorithm is designed to improve the real-time characteristics and complexity of general method. This algorithm use the latency and smoothing characteristics of exponential smoothing to achieve real-time calculation online. Using this algorithm, synchronous system can response to environmental changes in a short time. The test result shows that the real-time characteristics and output robustness can be improved obviously.

The Microstructure of Steatite (Protoenstatite)

1985 ◽  
Vol 43 ◽  
pp. 236-237
Author(s):  
W. E. Lee ◽  
A. H. Heuer
Keyword(s):  
High Frequency ◽  
Glass Ceramics ◽  
Magnesium Silicate ◽  
Beam Current ◽  
Glassy Matrix ◽  
Angle Of Incidence ◽  
X Ray ◽  
Mechanical And Electrical Properties ◽  
Argon Ions ◽  
High Temperature Polymorph

IntroductionTraditional steatite ceramics, made by firing (vitrifying) hydrous magnesium silicate, have long been used as insulators for high frequency applications due to their excellent mechanical and electrical properties. Early x-ray and optical analysis of steatites showed that they were composed largely of protoenstatite (MgSiO3) in a glassy matrix. Recent studies of enstatite-containing glass ceramics have revived interest in the polymorphism of enstatite. Three polymorphs exist, two with orthorhombic and one with monoclinic symmetry (ortho, proto and clino enstatite, respectively). Steatite ceramics are of particular interest a they contain the normally unstable high-temperature polymorph, protoenstatite.Experimental3mm diameter discs cut from steatite rods (∼10” long and 0.5” dia.) were ground, polished, dimpled, and ion-thinned to electron transparency using 6KV Argon ions at a beam current of 1 x 10-3 A and a 12° angle of incidence. The discs were coated with carbon prior to TEM examination to minimize charging effects.

Simulations of high-resolution images of amorphous silicon films

1986 ◽  
Vol 44 ◽  
pp. 544-545
Author(s):  
G. Y. Fan ◽  
J. M. Cowley
Keyword(s):  
Electron Microscope ◽  
High Frequency ◽  
Fourier Transformation ◽  
Amorphous Materials ◽  
Low Frequency ◽  
Chromatic Aberration ◽  
Structure Information ◽  
Frequency Components ◽  
High Resolution Images ◽  
Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

SEM image sharpness analysis

1996 ◽  
Vol 54 ◽  
pp. 142-143
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Quantitative Information ◽  
Primary Electron ◽  
Image Sharpness ◽  
Critical Dimensions ◽  
Sem Image ◽  
Frequency Changes ◽  
Electron Microscopes ◽  
Scanning Electron

Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or better) at 1.0 kV accelerating voltage for the measurement of nominal 0.25-0.35 micrometer semiconductor critical dimensions. Testing and proving that the instrument is performing at this level on a day-by-day basis is an industry need and concern which has been the object of a study at NIST and the fundamentals and results are discussed in this paper.In scanning electron microscopy, two of the most important instrument parameters are the size and shape of the primary electron beam and any image taken in a scanning electron microscope is the result of the sample and electron probe interaction. The low frequency changes in the video signal, collected from the sample, contains information about the larger features and the high frequency changes carry information of finer details. The sharper the image, the larger the number of high frequency components making up that image. Fast Fourier Transform (FFT) analysis of an SEM image can be employed to provide qualitiative and ultimately quantitative information regarding the SEM image quality.

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