CLIMTREG: Detecting temporal changes in climate–growth reactions – A computer program using intra-annual daily and yearly moving time intervals of variable width

2013 ◽  
Vol 31 (3) ◽  
pp. 232-241 ◽  
Author(s):  
Wolfgang Beck ◽  
Tanja G.M. Sanders ◽  
Ulrich Pofahl
Keyword(s):  
Computer Program ◽  
Temporal Changes ◽  
Time Intervals

A Method of Fitting Growth Curves of the von Bertalanffy Type to Observed Data

1966 ◽  
Vol 23 (2) ◽  
pp. 163-179 ◽  
Author(s):  
K. Radway Allen
Keyword(s):  
Computer Program ◽  
Least Squares ◽  
Growth Curves ◽  
Von Bertalanffy ◽  
Time Intervals ◽  
Type Formula ◽  
Numerical Example ◽  
Least Squares Estimates ◽  
Limits Of Error

A method is described for obtaining the best least-squares estimates of the parameters L∞, k, and t0 when von Bertalanffy curves of the type[Formula: see text]are fitted to observed data. This method imposes no restrictions on the number or size of the samples or on the time intervals between them. It also provides estimates of the limits of error of the parameters. The amount of computation is fairly large, but a method of systematizing it is described which makes manual computation practicable for moderate-sized sets of data. The method has been used to develop a computer program which seems to have advantages over some existing methods.A numerical example is worked out in full to illustrate application of the method.

scholarly journals Temporal changes in rainfall intensity-duration thresholds for post-wildfire flash floods and sensitivity to spatiotemporal distributions of rainfall

2021 ◽  
Author(s):  
Tao Liu ◽  
Luke A. McGuire ◽  
Nina Oakley ◽  
Forest Cannon
Keyword(s):  
Rainfall Intensity ◽  
Flash Flood ◽  
Flash Floods ◽  
Temporal Changes ◽  
Hydrologic Model ◽  
Model Parameters ◽  
Hydrologic Models ◽  
Time Intervals ◽  
Long Duration ◽  
Better Than

Abstract. Rainfall intensity-duration (ID) thresholds are commonly used to assess flash flood potential downstream of burned watersheds. High-intensity and/or long-duration rainfall is required to generate flash floods as landscapes recover from fire, but there is little guidance on how thresholds change as a function of time since burning. Here, we force a hydrologic model with radar-derived precipitation to estimate ID thresholds for post-fire flash floods in a 41.5 km2 watershed in southern California, USA. Prior work in this study area constrains temporal changes in hydrologic model parameters, allowing us to estimate temporal changes in ID thresholds. Results indicate that ID thresholds increase by more than a factor of 2 from post-fire year 1 to post-fire year 5. Thresholds based on averaging rainfall intensity over durations of 30–60 minutes perform better than those that average rainfall intensity over shorter time intervals. Moreover, thresholds based on the 75th percentile of radar-derived rainfall intensity over the watershed perform better than thresholds based on the 25th or 50th percentile of rainfall intensity. Results demonstrate how hydrologic models can be used to estimate changes in ID thresholds following disturbance and provide guidance on the rainfall metrics that are best suited for predicting post-fire flash floods.

Flower bud and root neoformation in thin cell layers of Nicotiana tabacum var. Samsun: a statistical analysis of spatial and temporal changes in mitotic activity

1990 ◽  
Vol 68 (11) ◽  
pp. 2501-2508 ◽  
Author(s):  
G. Mersch ◽  
C. Nassogne ◽  
A. Havelange
Keyword(s):  
Statistical Analysis ◽  
Nicotiana Tabacum ◽  
Mitotic Activity ◽  
Temporal Changes ◽  
Flower Bud ◽  
Time Intervals ◽  
Thin Cell Layers ◽  
Spatial And Temporal Changes ◽  
Cell Layers

Our aim was to analyse comparatively the spatial and temporal changes in mitotic activity in tobacco thin cell layers cultured in vitro during the expression of two organogenetic programs, namely the flower bud and root programs. These biological materials were found to be so complex and heterogeneous that we had to rely on sophisticated statistical models for the planned study. Using these models we could detect differences not only between the two programs, but also within each program between different time intervals and, in the flower bud program, between different longitudinal segments of the thin cell layers. Key words: Nicotiana tabacum, flower bud, root, statistical analysis, mitotic activity.

scholarly journals Search for temporal changes in the velocity of Ice Stream B, West Antarctica

1992 ◽  
Vol 38 (128) ◽  
pp. 157-161 ◽  
Author(s):  
J. McDonald ◽  
I. M. Whillans
Keyword(s):  
Temporal Changes ◽  
Velocity Variation ◽  
West Antarctica ◽  
Time Intervals ◽  
Ice Stream ◽  
Ice Stream B ◽  
Over Time

AbstractThe position of the UpB camp on Ice Stream B, West Antarctica, has been measured 14 times during three field seasons. TRANSIT (doppler) satellite receivers were used. At the resolution of our measurements (2 m), no significant velocity variation was detected over time intervals ranging from 1 d to 2 years.

scholarly journals Analysis of the competitive activity of qualified junior taekwondo athletes

2021 ◽  
pp. 44-59
Author(s):  
V. Romanenko ◽  
Y. Tropin ◽  
A. Kulida
Keyword(s):  
Computer Program ◽  
Computer Analysis ◽  
Video Analysis ◽  
Martial Arts ◽  
Practical Experience ◽  
Mathematical Statistics ◽  
Structural Components ◽  
Time Intervals ◽  
Competitive Activity

Purpose: to analyze the competitive activity of qualified junior taekwondo athletes. Material and methods. The research used the following methods: analysis of scientific and methodological information and Internet sources; generalization of best practical experience; video computer analysis of the competitive activity of qualified junior taekwondo athletes; methods of mathematical statistics. A specialized computer program «Martial Arts Video Analysis» was used to analyze the fights. The study analyzed the quarterfinal, semifinal and final fights, a total of 60 rounds (20 competitive fights) of qualified junior taekwondo fighters in weight categories in the 46-78 kg range. Results: analysis of scientific and methodological information and generalization of advanced practical experience made it possible to reveal that successful training of taekwondo fighters of any level is impossible without a thorough analysis of the structural components of the competitive activity of the world's leading athletes. Based on the study, it was found that the winners receive more points, with the same number of actions with the losers, due to the quality of the performance of technical and tactical actions and their diversity (on average, 3,25 points more than the losers). It was noted that in the 3rd round, regardless of weight categories, there is a statistically significant increase in the number of actions (t=3,07; p<0,01), a decrease in the time intervals between actions (t=1,81; p<0,05) , the number of points received increases (t=1,76; p <0,05). Conclusions. The analysis of competitive activity made it possible to determine the arsenal of technical and tactical actions of qualified junior taekwondo athletes, depending on their weight categories, thanks to which combatants receive victory points. So, the actions that athletes perform more often and receive the greatest number of points for them include: for weight categories 46-52 kg – «Dollyeo Chagi», for categories 55-59 kg – «Dollyeo Chagi», «Naeryeo Chagi», for categories 63-68 kg – «Dollyeo Chagi», «Dollyeo Chagi», for categories 73-78 kg – «Yeop Chagi», «Dollyeo Chagi», «Naeryeo Chagi». Keywords: competitive activity, indicators, taekwondo, qualified athletes, computer program.

scholarly journals Possible Changes in the Core-Mantle and Inner-Outer Core Boundaries

1972 ◽  
Vol 48 ◽  
pp. 179-181
Author(s):  
J. A. Jacobs
Keyword(s):  
Outer Core ◽  
Temporal Changes ◽  
Time Intervals ◽  
Earth’S Core ◽  
Earth's Core ◽  
Size And Shape ◽  
The Core ◽  
Earth’S Mantle ◽  
Short Time

This paper investigates the possibility that the boundaries between the Earth's mantle and core and between the inner and outer core might show temporal changes. The evolution of the Earth's core is not discussed, but the question is raised as to whether these boundaries might not undergo small changes both in size and shape over comparatively short time intervals.

scholarly journals Search for temporal changes in the velocity of Ice Stream B, West Antarctica

1992 ◽  
Vol 38 (128) ◽  
pp. 157-161 ◽  
Author(s):  
J. McDonald ◽  
I. M. Whillans
Keyword(s):  
Temporal Changes ◽  
Velocity Variation ◽  
West Antarctica ◽  
Time Intervals ◽  
Ice Stream ◽  
Ice Stream B ◽  
Over Time

AbstractThe position of the UpB camp on Ice Stream B, West Antarctica, has been measured 14 times during three field seasons. TRANSIT (doppler) satellite receivers were used. At the resolution of our measurements (2 m), no significant velocity variation was detected over time intervals ranging from 1 d to 2 years.

Rotational Characteristics of the Green Solar Corona: 1947-1991

1994 ◽  
Vol 144 ◽  
pp. 139-141 ◽  
Author(s):  
J. Rybák ◽  
V. Rušin ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
World Wide ◽  
Rotation Period ◽  
Original Data ◽  
Coronal Emission ◽  
Time Intervals ◽  
Data Set ◽  
The World ◽  
Coronal Emission Line ◽  
Homogeneous Data

AbstractFe XIV 530.3 nm coronal emission line observations have been used for the estimation of the green solar corona rotation. A homogeneous data set, created from measurements of the world-wide coronagraphic network, has been examined with a help of correlation analysis to reveal the averaged synodic rotation period as a function of latitude and time over the epoch from 1947 to 1991.The values of the synodic rotation period obtained for this epoch for the whole range of latitudes and a latitude band ±30° are 27.52±0.12 days and 26.95±0.21 days, resp. A differential rotation of green solar corona, with local period maxima around ±60° and minimum of the rotation period at the equator, was confirmed. No clear cyclic variation of the rotation has been found for examinated epoch but some monotonic trends for some time intervals are presented.A detailed investigation of the original data and their correlation functions has shown that an existence of sufficiently reliable tracers is not evident for the whole set of examinated data. This should be taken into account in future more precise estimations of the green corona rotation period.

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