scholarly journals Energy distribution and effective components analysis of 2 sequence pseudo-random signal

2021 ◽  
Vol 31 (7) ◽  
pp. 2102-2115
Author(s):  
Yang YANG ◽  
Ji-shan HE ◽  
Di-quan LI
Author(s):  
Tamotsu Ohno

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.


Author(s):  
Thomas W. Shattuck ◽  
James R. Anderson ◽  
Neil W. Tindale ◽  
Peter R. Buseck

Individual particle analysis involves the study of tens of thousands of particles using automated scanning electron microscopy and elemental analysis by energy-dispersive, x-ray emission spectroscopy (EDS). EDS produces large data sets that must be analyzed using multi-variate statistical techniques. A complete study uses cluster analysis, discriminant analysis, and factor or principal components analysis (PCA). The three techniques are used in the study of particles sampled during the FeLine cruise to the mid-Pacific ocean in the summer of 1990. The mid-Pacific aerosol provides information on long range particle transport, iron deposition, sea salt ageing, and halogen chemistry.Aerosol particle data sets suffer from a number of difficulties for pattern recognition using cluster analysis. There is a great disparity in the number of observations per cluster and the range of the variables in each cluster. The variables are not normally distributed, they are subject to considerable experimental error, and many values are zero, because of finite detection limits. Many of the clusters show considerable overlap, because of natural variability, agglomeration, and chemical reactivity.


1983 ◽  
Vol 26 (1) ◽  
pp. 2-9 ◽  
Author(s):  
Vincent J. Samar ◽  
Donald G. Sims

The relationship between the latency of the negative peak occurring at approximately 130 msec in the visual evoked-response (VER) and speechreading scores was investigated. A significant product-moment correlation of -.58 was obtained between the two measures, which confirmed the fundamental effect but was significantly weaker than that previously reported in the literature (-.90). Principal components analysis of the visual evoked-response waveforms revealed a previously undiscovered early VER component, statistically independent of the latency measure, which in combination with two other components predicted speechreading with a multiple correlation coefficient of S4. The potential significance of this new component for the study of individual differences in speechreading ability is discussed.


2000 ◽  
Vol 16 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Lina Pezzuti ◽  
Caterina Laicardi ◽  
Marco Lauriola

Summary: An Elderly Behavior Assessment for Relatives (EBAR), updating the GERRI ( Schwartz, 1983 ), was administered to relatives (or significant others) of 349 elderly persons, from 60 to over 80 years of age, living at home, in good health and without cognitive impairment. A trained psychologist administered subjects the Life Satisfaction for Elderly Scale (LSES), the Instrumental Activity of Daily Living (IADL), the Mini Mental State Examination (MMSE), and personally answered to an overall elderly behavior rating scale (RA). EBAR items were first examined. The more attractive and less discriminative statements were excluded. A principal components analysis was carried out on the remaining EBAR items. Three factors were extracted. After varimax rotation they were tentatively labeled: Everyday Cognitive Functioning, Depression, and Hostility. Factor-driven EBAR subscales were designed, taking into account simpler items in the factor matrix. Results provide evidence for EBAR construct validity. Everyday Cognitive Functioning is connected to the IADL and the RA scores; Depression is very highly related to the LSES; Hostility is weakly related to RA, IADL, and MMSE, indicating that the scale needs further investigation.


1998 ◽  
Vol 14 (2) ◽  
pp. 116-123 ◽  
Author(s):  
Raymond M. Costello

This is an empirical examination of Experienced Stimulation (es) and Experience Actual (EA) from Exner's Comprehensive System (CS) for Rorschach's Test, spurred by Kleiger's theoretical critique. Principal components analysis, Cronbach's α, and inter-item correlational analyses were used to test whether 13 determinants used to code Rorschach responses (M, FM, m, CF+C, YF+Y, C'F+C', TF+T, VF+V, FC, FC', FV, FY, FT) are best represented as a one, two, or more-dimensional construct. The 13 determinants appear to reflect three dimensions, a “lower order” sensori-motor dimension (m + CF+C + YF+Y + C'F+C' + TF+T + VF+V) with a suggested label of Modified Experienced Stimulation (MES), a “higher order” sensori-motor dimension (FM + FV + FY + FT) with a suggested label of Modified Experience Potential (MEP), and a third sensori-motor dimension (M+FC+FC') for which the label of Modified Experience Actual (MEA) is suggested. These findings are consistent with Kleiger's arguments and could lead to a refinement of CS constructs by aggregating determinants along lines more theoretically congruous and more internally consistent. A RAMONA model with parameters specified was presented for replication attempts which use confirmatory factor analytic techniques.


2016 ◽  
Vol 32 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Marianna Szabó ◽  
Veronika Mészáros ◽  
Judit Sallay ◽  
Gyöngyi Ajtay ◽  
Viktor Boross ◽  
...  

Abstract. The aim of the present study was to examine the construct and cross-cultural validity of the Beck Hopelessness Scale (BHS; Beck, Weissman, Lester, & Trexler, 1974 ). Beck et al. applied exploratory Principal Components Analysis and argued that the scale measured three specific components (affective, motivational, and cognitive). Subsequent studies identified one, two, three, or more factors, highlighting a lack of clarity regarding the scale’s construct validity. In a large clinical sample, we tested the original three-factor model and explored alternative models using both confirmatory and exploratory factor analytical techniques appropriate for analyzing binary data. In doing so, we investigated whether method variance needs to be taken into account in understanding the structure of the BHS. Our findings supported a bifactor model that explicitly included method effects. We concluded that the BHS measures a single underlying construct of hopelessness, and that an incorporation of method effects consolidates previous findings where positively and negatively worded items loaded on separate factors. Our study further contributes to establishing the cross-cultural validity of this instrument by showing that BHS scores differentiate between depressed, anxious, and nonclinical groups in a Hungarian population.


2008 ◽  
Vol 42 (2) ◽  
pp. 125-128
Author(s):  
J. F. Al-Sharab ◽  
J. E. Wittig ◽  
G. Bertero ◽  
T. Yamashita ◽  
J. Bentley ◽  
...  

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-385-C7-386
Author(s):  
S. Bourquard ◽  
J. M. Mayor ◽  
P. Kocian

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