scholarly journals New Orthogonal Small Set Kasami Code Sequence

2015 ◽  
Vol 14 (1) ◽  
Author(s):  
I Nyoman Pramaita ◽  
I G.A.G.K. Diafari ◽  
DNKP Negara ◽  
Agus Dharma
Keyword(s):  
Correlation Function ◽  
Cross Correlation ◽  
Code Sequence ◽  
Cross Correlation Function ◽  
Auto Correlation ◽  
M Sequence ◽  
Auto Correlation Function ◽  
Small Set

In this paper, the authors propose the design of a new orthogonal small set Kasami code sequence generated using combination of non-orthogonal m-sequence and small set Kasami code sequence. The authors demonstrate that the proposed code sequence has comparable auto-correlation function (ACF), cross- correlation function (CCF), peak cross-correlation values with that of the existing orthogonal small set Kasami code sequence. Though the proposed code sequence has less code sequence sets than that of the existing orthogonal small set Kasami code sequence, the proposed code sequence possesses one more numbers of members in each code sequence set. The members of the same code set of the proposed code sequence are orthogonal to each other.

A New Scheme for the Exit-Wave Reconstruction from a Small Set of Focus Series of HREM Images

2005 ◽  
Vol 475-479 ◽  
pp. 4059-4062
Author(s):  
F. Lin ◽  
Qing Chen ◽  
Lian Mao Peng
Keyword(s):  
Electron Microscopy ◽  
Genetic Algorithm ◽  
Correlation Function ◽  
High Resolution ◽  
Cross Correlation ◽  
High Resolution Electron Microscopy ◽  
Cross Correlation Function ◽  
Electron Wave ◽  
Resolution Electron ◽  
Small Set

A new procedure is proposed for the exit electron wave reconstruction using a small set of high-resolution electron microscopy (HREM) images. This procedure is similar to that proposed by van Dyck and coworkers, but the relative shifts between different HREM images are obtained via the genetic algorithm instead of the more widely used cross-correlation function (XCF) method. The new procedure is demonstrated using simulated HREM images with added noise, and shown to be able to deal with situation where the scheme based on the method of XCF is not applicable.

The Correlation and Spectrum Research on Cylindrical Surface Lapping Machined with Abrasive Jet Finishing Restricted by Grinding Wheel

2008 ◽  
Vol 389-390 ◽  
pp. 320-325
Author(s):  
Feng Liu ◽  
Ya Dong Gong ◽  
Yu Qiao Shan ◽  
Guang Qi Cai
Keyword(s):  
Correlation Function ◽  
Cross Correlation ◽  
Low Frequency ◽  
Grinding Wheel ◽  
Small Range ◽  
Auto Correlation ◽  
Surface Contour ◽  
Power Spectral ◽  
Finishing Process ◽  
Auto Correlation Function

With the correlation in stochastic process applied to the experimental results, the surface during grinding and further lapping with abrasive jet finishing (AJF) restricted by grinding wheel was investigated with respect to auto correlation function (ACF) , cross correlation function (CCF) and power spectral density (PSD) analysis. The results indicated that AJF made the surface contour formed periodicity in a small range and removed fluctuation of the surface contour in low frequency greatly. The average spacing of the surface contour decreased and the machined surfaces changed from continuous parallel micro-groove and plough to randomly distributed discontinuous micro-pit with the increase of machining circles. The surface texture became fine and surface roughness was obviously improved. Furthermore, the isotropy surface and uniformity veins both parallel and perpendicular machining direction was attained by the finishing process to improve greatly the wearable capability of the workpiece.

scholarly journals Use of Cross-Correlation Function to Study Formation Mechanism of Massive Elliptical Galaxies

2014 ◽  
Vol 31 ◽  
Author(s):  
Tuli De ◽  
Tanuka Chattopadhyay ◽  
Asis Kumar Chattopadhyay
Keyword(s):  
Correlation Function ◽  
Cross Correlation ◽  
Spatial Clustering ◽  
High Redshift ◽  
Elliptical Galaxies ◽  
Cross Correlation Function ◽  
Redshift Range ◽  
Auto Correlation Function ◽  
Highly Correlated ◽  
Stellar Masses

AbstractSpatial clustering nature of galaxies has been studied previously through auto correlation function. The same type of cross-correlation function has been used in the present work to investigate parametric clustering nature of galaxies with respect to masses and sizes of galaxies. Here, formation and evolution of several components of nearby massive early type galaxies (M*≥ 1.3 × 1011M⊙have been envisaged through cross-correlations, in the mass-size parametric plane, with high redshift (0.2 ⩽z⩽ 7) ETGs. It is found that the inner most components of nearby ETGs have significant correlation (~ 0.5 ± (0.02–0.07)) with ETGs in the highest redshift range (2 ⩽z⩽ 7) called ‘red nuggets’ whereas intermediate components are highly correlated (~ 0.65 ± (0.03–0.07)) with ETGs in the redshift range 0.5 ⩽z⩽ 0.75. The outermost part has no correlation in any range, suggesting a scenario throughin situaccretion. The above formation scenario is consistent with the previous results obtained for NGC5128 and to some extent for nearby elliptical galaxies after considering a sample of ETGs at high redshift with stellar masses greater than or equal to 108.73M⊙. So the present work indicates a three phase formation instead of two as discussed in previous works.

A FLUX-FLUX CROSS-CORRELATION FUNCTION APPROACH TO SELF-DIFFUSION OF HYDROGEN ATOM ON A CU(111) SURFACE

2005 ◽  
Vol 04 (01) ◽  
pp. 209-223
Author(s):  
TOSHIAKI TANIIKE ◽  
KOICHI YAMASHITA
Keyword(s):  
Correlation Function ◽  
Hydrogen Atom ◽  
Rate Constants ◽  
Cross Correlation ◽  
Diffusion Constant ◽  
Function Approach ◽  
Cross Correlation Function ◽  
Self Diffusion ◽  
Auto Correlation Function ◽  
Dividing Surface

We have employed a flux-flux cross-correlation function approach (CCFA) to calculate quantum thermal rate constants of reactions for which an auto-correlation function approach (ACFA) is not adequate. In CCFA, two dividing surfaces partition a system into three regions, while in ACFA, two channels are defined by a dividing surface. Therefore, the CCFA method is appropriate for multi-channel reactions. In this paper, we show the efficiency of CCFA for multi-channel reactions. For example, we have examined self-diffusion of a hydrogen atom on a rigid Cu (111) surface. We introduce closed dividing surfaces that subdivide the potential energy surface for each channel. A combination of the closed dividing surfaces and CCFA allows us to calculate rate constants for both single and multi-hopping modes directly. Then, we calculate a diffusion constant without the usual uncorrelated hops approximation, using instead the calculated site-to-site hopping rates, thus showing the importance of multihops.

scholarly journals Clustering of galaxies around quasars at z ∼ 4

2019 ◽  
Vol 15 (S352) ◽  
pp. 171-173
Author(s):  
Cristina García-Vergara ◽  
Joseph F. Hennawi ◽  
L. Felipe Barrientos ◽  
Fabrizio Arrigoni Battaia
Keyword(s):  
Dark Matter ◽  
Correlation Function ◽  
Cross Correlation ◽  
Dark Matter Halos ◽  
Lyman Alpha ◽  
Alpha Emitters ◽  
Lyman Break Galaxies ◽  
Auto Correlation ◽  
Auto Correlation Function ◽  
Lyman Alpha Emitters

AbstractWe conduct a survey for Lyman break galaxies (LBGs) and Lyman alpha emitters (LAEs) in the environs of six and 17 z ∼ 4 quasars respectively, probing scales of R≲9h−1Mpc. We detect an enhancement of galaxies (both LBGs and LAEs) in quasar fields, a positive and strong quasar-galaxy cross-correlation function, consistent with a power-law shape, and a strong galaxy auto-correlation function in quasar fields. The three mentioned results are all indicators that quasars trace massive dark matter halos in the early universe.

Research on Improved Code Phase Acquisition Algorithm for BOC(pn,n) Signal

2013 ◽  
Vol 427-429 ◽  
pp. 1794-1798
Author(s):  
Yin Bing Zhu ◽  
Ke Jing Cao ◽  
Bao Li
Keyword(s):  
Correlation Function ◽  
Cross Correlation ◽  
Search Algorithm ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Low Snr ◽  
Auto Correlation ◽  
Auto Correlation Function ◽  
Parallel Code ◽  
Improved Algorithm

Auto correlation function of BOC signal has the character of milti-values, so acquistion of BOC signal can not simply transplant the algorithm of GPS signal. For this reason, parallel code phase search algorithm and cross correlation characteristics of BOC signal are analyzed. And then, the validity of parallel code phase search algorithm on BOC signal are simulated. After that, point to the insufficiency of parallel code phase search algorithm on the acquisiton of BOC signal at low SNR(signal to noise ratio), an improved acquisition algorithm is presented and used to analyze BOC signal. The results show that the improved algorithm is applicable to BOC(pn, n) signal where p is an integer, which expands the application aera of parallel code phase search algorithm; and that the improved algorithm can improve SNR of acquisition about 15dB compared with that of parallel code phase search algorithm, that is to say, the improved algorithm can enhance acquisiton sensitivity of receivers obviously, which is very important to the design of acquisiton algorithm in receivers.

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