Properties of random functions

1956 ◽  
Vol 52 (4) ◽  
pp. 672-686 ◽  
Author(s):  
D. S. Palmer
Keyword(s):  
Cross Correlation ◽  
The Other ◽  
Horizontal Line ◽  
Time Lags ◽  
Frequency Distributions ◽  
Random Functions ◽  
Wave Radio ◽  
Long Wave ◽  
Radio Signals ◽  
Highly Correlated

ABSTRACTThis paper deals with the relationships of the maxima, minima and zeros of two random functions of known autocorrelations and cross-correlation, based on the work of Rice(4). Ratcliffe(3) and Briggs and Spencer(2) discuss a similar problem in connexion with a ‘Phillips Record’ of an experiment in ionospheric reflexion. In this experiment there are two highly correlated reflected signals, their maxima coming close together, and the record shows the time lags between a maximum on one signal and a maximum on the other. Briggs and Page (1) have made an experimental study of the distribution of the differences between the positions of the maxima of two highly correlated random functions, using EDSAC to construct the functions. In §§ 3–7 the frequency distributions of intervals between successive zeros and maxima, and of the lengths of intercepts by a horizontal line, are considered. This has applications to the study of the fading of long-wave radio signals, where the tune differences between successive maxima of the amplitude have been investigated.

Contributions of ventilation and perfusion inhomogeneities to the VA/Q distribution

1992 ◽  
Vol 72 (6) ◽  
pp. 2298-2304 ◽  
Author(s):  
T. A. Wilson ◽  
K. C. Beck
Keyword(s):  
Vertical Gradient ◽  
The Other ◽  
Independent Data ◽  
Frequency Distributions ◽  
Highly Correlated ◽  
Using Data ◽  
Additional Variance ◽  
Exchange Data ◽  
Ventilation And Perfusion ◽  
Vertical Gradients

The anatomic distributions of ventilation (VA) and perfusion (Q) in prone and supine dogs have been described in the literature. These data also provide frequency distributions, i.e., the distribution of lung units as a function of VA or Q. A comprehensive distribution that encompasses these two distributions is described, and the properties of the comprehensive distribution that determine the width of the VA/Q distribution are identified. Using data on the VA and Q distributions taken from various sources in the literature, we estimated the widths of the VA/Q distributions. The widths estimated from the independent data on the VA and Q distributions agree well with the widths obtained from gas exchange data. The analysis provides information about the relative contributions of the VA and Q distributions to the width of the VA/Q distribution. In the prone dog, the VA and Q distributions, as described by the available data, have different length scales, and we argue that these distributions are therefore not highly correlated. As a result, the variance of the VA/Q distributions is approximately the sum of the variances of the VA and Q distributions. Two-thirds of the variance in VA/Q is a result of nonuniform Q, and one-third is a result of nonuniform VA. In the supine dog, the variance of VA is larger than in the prone dog because of a vertical gradient and the variance of Q is larger, in part, because of a vertical gradient. Because the magnitudes of the vertical gradients of VA and Q are about equal, the vertical gradient of VA/Q is small, and these components of the VA and Q inhomogeneities contribute little to the width of the VA/Q distribution. The other components of Q inhomogeneity cause the additional variance of VA/Q in the supine dog.

scholarly journals Analysis of the cross-correlation between seismicity and water level in the Aswan area (Egypt) from 1982 to 2010

2012 ◽  
Vol 12 (7) ◽  
pp. 2203-2207 ◽  
Author(s):  
L. Telesca ◽  
R. ElShafey Fat ElBary ◽  
A. El-Ela Amin Mohamed ◽  
M. ElGabry
Keyword(s):  
Water Level ◽  
Cross Correlation ◽  
Time Lag ◽  
The Other ◽  
Time Lags ◽  
Surrounding Area ◽  
Pressure Diffusion ◽  
Triggering Mechanisms ◽  
Deep Seismicity ◽  
Aswan High Dam

Abstract. In this study the correlation between the monthly fluctuations of the water level of the Aswan High Dam and monthly number of earthquakes from 1982 to 2010, which occurred in the surrounding area, was investigated. Our findings reveal that significant correlation is present during the period 1982–1993 between water level and shallow seismicity (depth less than 15 km). The deep seismicity (depth larger than 15 km) is significantly correlated with the water level between January and April 1989. The time lag of the significant maximal cross-correlation varies from 2–8~months for the shallow seismicity, while it is around 7–8 months for the deep seismicity. These values of the time lags could be in favour of the presence of two distinct triggering mechanisms: one due to pore pressure diffusion and the other due to fracture compaction (undrained response).

Correlational Methods for Analysis of Dance Movements

2011 ◽  
Vol 29 (supplement) ◽  
pp. 283-304 ◽  
Author(s):  
Timothy R. Brick ◽  
Steven M. Boker
Keyword(s):  
Motion Capture ◽  
Mirror Symmetry ◽  
Cross Correlation ◽  
The Other ◽  
Free Form ◽  
Motion Capture Data ◽  
Complex Interactions ◽  
Dance Movements ◽  
Time Lagged ◽  
Insight Into

Among the qualities that distinguish dance from other types of human behavior and interaction are the creation and breaking of synchrony and symmetry. The combination of symmetry and synchrony can provide complex interactions. For example, two dancers might make very different movements, slowing each time the other sped up: a mirror symmetry of velocity. Examining patterns of synchrony and symmetry can provide insight into both the artistic nature of the dance, and the nature of the perceptions and responses of the dancers. However, such complex symmetries are often difficult to quantify. This paper presents three methods – Generalized Local Linear Approximation, Time-lagged Autocorrelation, and Windowed Cross-correlation – for the exploration of symmetry and synchrony in motion-capture data as is it applied to dance and illustrate these with examples from a study of free-form dance. Combined, these techniques provide powerful tools for the examination of the structure of symmetry and synchrony in dance.

SOIL MORPHOLOGY AND SOIL PHYSICAL PROPERTIES. I. SOIL AERATION

1972 ◽  
Vol 52 (3) ◽  
pp. 311-321 ◽  
Author(s):  
K. W. AYRES ◽  
R. G. BUTTON ◽  
E. DE JONG
Keyword(s):  
Soil Structure ◽  
Regression Coefficient ◽  
The Other ◽  
Soil Morphology ◽  
Soil Horizons ◽  
Undisturbed Soil ◽  
Soil Aeration ◽  
Structural Types ◽  
Highly Correlated ◽  
Undisturbed Soil Cores

The relation between soil structure and soil aeration was investigated on undisturbed soil cores from soil horizons exhibiting six distinct kinds of soil structure (prismatic, columnar, blocky, granular, platy, massive) over a broad range of soil texture. Soil aeration was characterized at ⅓ atm suction by measurements of air porosity, relative diffusivity (D/Do) and the rate of oxygen diffusion to a platinum microelectrode (ODR). Aeration was adequate in most of the Chernozemic soil horizons studied; however, aeration in many of the Bnt horizons of the Solonetzic soils was inadequate. Air porosity and D/Do were highly correlated. The regression coefficient for D/Do vs. air porosity for blocky structures was significantly different from that found for the other five structural types. For granular structures a negative correlation was found for ODR vs. air porosity compared with a low positive correlation found for the other structure types.

Examining the validity of three methods of measuring pre-readers’ knowledge of storybook events

2021 ◽  
pp. 026565902199554
Author(s):  
Lynn Dempsey
Keyword(s):  
The Other ◽  
Narrative Comprehension ◽  
Important Predictor ◽  
Story Comprehension ◽  
Typically Developing ◽  
Typically Developing Children ◽  
Event Knowledge ◽  
Yield Information ◽  
Highly Correlated ◽  
Planning Intervention

Planning intervention for narrative comprehension deficits requires a thorough understanding of a child’s skill in all component domains. The purpose of this study was to examine the validity of three methods of measuring pre-readers’ event knowledge, an important predictor of story comprehension. Thirty-eight typically developing children (12 males; 26 females) between the ages of 30–59 months ( M = 42.05 SD = 7.62) completed three measures – verbal account, enactment, picture-sequencing – that tapped their knowledge of two different events before listening to stories based on each of those events and completing story comprehension tasks. Scores for verbal account and enactment, but not for picture sequencing, (1) were moderately correlated with comprehension scores for the corresponding story; (2) reflected differential knowledge of the two events, though not in the expected direction; (3) were moderately correlated with one another in the case of each story. In general measures for the same event were more highly correlated with one another than with measures of the other event. Overall, results suggest that verbal account and enactment may yield information useful for clinicians planning intervention for children with narrative comprehension deficits.

A New Test of Auditory-Visual Integration

1973 ◽  
Vol 36 (3_suppl) ◽  
pp. 1063-1066 ◽  
Author(s):  
Andrew H. Gregory ◽  
H. Margaret Gregory
Keyword(s):  
Reading Ability ◽  
The Other ◽  
Nonverbal Intelligence ◽  
Visual Integration ◽  
Morse Form ◽  
Highly Correlated

Two auditory-visual integration tests were given to 86 children from 6 yr. to 11 yr. One test was basically that developed by Birch; the other used Morse-type stimuli. The children were also given tests of nonverbal intelligence, reading and vocabulary. With age and intelligence partialled out, the Morse form of test was significantly more highly correlated with reading ability than the Birch test. Reasons are suggested as to why the Morse version may be a better test of some of the underlying skills involved in reading.

Estimation of Construction Waste Generation and Management in Taiwan

2011 ◽  
Vol 243-249 ◽  
pp. 6292-6295 ◽  
Author(s):  
Rong Yau Huang ◽  
Li Hsu Yeh ◽  
Hao Hsien Chen ◽  
Jyh Dong Lin ◽  
Ping Fu Chen ◽  
...  
Keyword(s):  
Decision Tree ◽  
Cross Correlation ◽  
Expert Interviews ◽  
Waste Generation ◽  
Valid Conclusion ◽  
Construction Waste ◽  
Composition Ratio ◽  
The Past ◽  
Highly Correlated ◽  
Using Data

This study examines construction waste generation and management in Taiwan. We verify the factors probable affecting the output of construction wastes by using data for the output of declared construction wastes produced from demolition projects in Taiwan in the last year, expert interviews, and research achievements in the past, and find “ on-site separation” is the factor with effects on the output of construction wastes via cross-correlation by algorithms such as K-Means and Decision Tree C5.0. It can be seen that the output (0.092(t/M3) with on-site separation or 0.329(t/M3) without on-site separation is highly correlated with the composition ratio of construction wastes and referred to as a valid conclusion.

The Semantic Differential as an Index of Traffic Sign Perception and Comprehension

1977 ◽  
Vol 19 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Robert E. Dewar ◽  
Jerry G. Ells
Keyword(s):  
Semantic Differential ◽  
The Other ◽  
Traffic Sign ◽  
Two Factors ◽  
Valid Instrument ◽  
Paper And Pencil ◽  
Verbal Messages ◽  
Highly Correlated

There is a need to develop and validate simple, inexpensive techniques for the evaluation of traffic sign messages. This paper examines the semantic differential (a paper-and-pencil test which measures psychological meaning) as a potential instrument for such evaluation. Two experiments are described, one relating semantic differential scores to comprehension and the other relating this index to glance legibility. The data indicate that semantic differential scores on all four factors (evaluative, activity, potency, and understandability) were highly correlated with comprehension of symbolic messages. These scores were unrelated to glance legibility of verbal messages, but two factors (evaluative and understandability) did correlate with glance legibility of symbolic messages. It was concluded that the semantic differential is a valid instrument for evaluating comprehension of symbolic sign messages and that it has advantages over other techniques.

scholarly journals The spectrum of thallium fluoride

1937 ◽  
Vol 160 (901) ◽  
pp. 242-253 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Kinetic Energy ◽  
The Other ◽  
Molecular Spectra ◽  
Absorption Tube ◽  
Saturated Vapour ◽  
Long Wave ◽  
Original Investigation ◽  
Wave Edge

This study of the thallium fluoride spectrum was undertaken as part of a detailed investigation into the molecular spectra of the series of heavy diatomic fluorides HgF, TlF, PbF and BiF. Whereas the spectra of PbF (Rochester 1936) and BiF (Howell 1936), of which analyses have already been published, contain no very unusual features the TlF spectrum is particularly rich in them, so that it has seemed desirable to extend the original investigation in order to include the other halides of thallium. The absorption spectrum of the fluoride has already been examined by Boizova and Butkow (1936), their findings being summarized below: 1— A continuum at 2200 A appears when the absorption tube is at a temperature of 155° C. Its long-wave edge moves towards the red with increase of temperature, being at 2700 for the unsaturated vapour and at 3400 for the saturated vapour when the temperature is 280° C. They attributed this continuum to the dissociation of Tl 2 F 2 . Tl 2 F 2 → 2TlF + kinetic energy.

scholarly journals Two new species of the genus Crenicichla Heckel, 1840 from the upper rio Uruguay drainage (Perciformes: Cichlidae)

2007 ◽  
Vol 5 (4) ◽  
pp. 449-456 ◽  
Author(s):  
Carlos A. S. de Lucena
Keyword(s):  
New Species ◽  
Species Group ◽  
The Body ◽  
The Other ◽  
Horizontal Line ◽  
Lower Edge ◽  
Middle Portion ◽  
Lateral Band ◽  
Two New Species ◽  
Vertical Bars

Two new species of the genus Crenicichla from the upper rio Uruguay basin are described, Crenicichla hadrostigma and C. empheres. Both are included in the C. missioneira species group along with C. missioneira, C. minuano, C. tendybaguassu, C. igara, and C. jurubi, all occurring in the upper and middle rio Uruguay drainage. Crenicichla hadrostigma is distinguished by the conspicuous ocellated posttemporal blotch, absence of a humeral spot and lateral band, and the presence in males of nine to 16 narrow vertical bars extending from the dorsum to a horizontal line that passes through the lower edge of pectoral axilla. Crenicichla empheres is distinguished from the other species of the missioneira-group by the presence of six to eight horizontally elongate dark blotches along the middle portion of the body, slightly below the upper lateral line, absence of a lateral band, presence in males of numerous dark and irregularly arranged spots on nape, back, and sides of body, and isognathous mouth. A key to the species from rio Uruguay basin is presented.

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