Role Of Parameter Estimation And Correlation Techniques In Remote Imaging With Emphasis On Signal Attenuation In Varied Media.

Abstract Uncertainty in cumulus convection parameterization is one of the most important causes of model climate drift through interactions between large-scale background and local convection that use empirically set parameters. Without addressing the large-scale feedback, the calibrated parameter values within a convection scheme are usually not optimal for a climate model. This study first designs a multiple-column atmospheric model that includes large-scale feedbacks for cumulus convection and then explores the role of large-scale feedbacks in cumulus convection parameter estimation using an ensemble filter. The performance of convection parameter estimation with or without the presence of large-scale feedback is examined. It is found that including large-scale feedbacks in cumulus convection parameter estimation can significantly improve the estimation quality. This is because large-scale feedbacks help transform local convection uncertainties into global climate sensitivities, and including these feedbacks enhances the statistical representation of the relationship between parameters and state variables. The results of this study provide insights for further understanding of climate drift induced from imperfect cumulus convection parameterization, which may help improve climate modeling.

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Studies on some diseases of fruits and vegetable crops in relation to meteorological parameters

MAUSAM ◽

10.54302/mausam.v51i3.1785 ◽

2021 ◽

Vol 51 (3) ◽

pp. 269-274

Author(s):

S. V. DATAR ◽

R. C. DUBEY ◽

N. CHATTOPADHYAY

Keyword(s):

Relative Humidity ◽

Minimum Temperature ◽

Early Blight ◽

Meteorological Parameters ◽

Maximum Temperature ◽

Vegetable Crops ◽

Correlation Techniques

The role of different meteorological parameters controlling the incidences of some diseases on tomato, guava and fig grown at Pune and Padegaon in Maharashtra state were studied by graphical superimposition and correlation techniques. Peak infestation of rust on fig was observed in January at Padegaon whereas maximum infestation of fruit canker on guava and early blight on tomato were reported respectively from September to first week of October and September to November at Pune. Increase in maximum temperature was found to increase the infestation of both fruit canker and early blight. Decrease in afternoon relative humidity favoured the infestation of fruit canker and rust. Fall of minimum temperature and rise in bright hours of sunshine also aggravated the incidences of fruit canker and rust respectively.

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Review of “Further Insights on the Role of Accurate State Estimation in Coupled Model Parameter Estimation by a Simple Climate Model Study” by Yu et al.

10.5194/npg-2016-52-rc2 ◽

2016 ◽

Author(s):

Anonymous

Keyword(s):

Parameter Estimation ◽

State Estimation ◽

Climate Model ◽

Coupled Model ◽

Simple Climate Model ◽

Model Parameter ◽

Model Parameter Estimation ◽

Model Study

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Parameter estimation aspects and the role of bandwidth in a notch filter

10.1109/cdc.1982.268369 ◽

1982 ◽

Author(s):

D. V. Bhaskar Rao ◽

Sun-yuan Kung

Keyword(s):

Parameter Estimation ◽

Notch Filter

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The role of within-species differentiation in macroevolution of Chesapeake Group bivalves

Paleobiology ◽

10.1017/s0094837300007673 ◽

1983 ◽

Vol 9 (3) ◽

pp. 261-268 ◽

Cited By ~ 7

Author(s):

Patricia H. Kelley

Keyword(s):

Discriminant Function ◽

Discriminant Function Analysis ◽

Species Differences ◽

Function Analysis ◽

Rank Correlation ◽

Species Differentiation ◽

Separate Species ◽

Geographic Populations ◽

Correlation Techniques

Discriminant function analysis is used to examine the role of within-species differentiation in macroevolution of four Miocene bivalve genera. According to the punctuational model, macroevolution is decoupled from microevolution; within-species trends may be unrelated to between-species differences. The reductionist alternative suggests that intraspecific (primarily geographic) differentiation is the basis of macroevolution. If macroevolution depends on within-species differentiation, discriminant function analysis should separate interspecific and intraspecific populations of a genus using the same set of characters.Chesapecten macroevolution apparently involved within-species differentiation. Shell length, height, and posterior auricle length differentiate geographic populations within species as well as interspecific populations. Results for Astarte, Anadara, and Eucrassatella are more consistent with the punctuational model. Characters which readily separate species of a genus are much less successful at differentiating intraspecific populations. Rank correlation techniques indicate that, for all three genera, the order of importance of characters in interspecific discrimination is not significantly related to their order in intraspecific discrimination. Decoupling of macroevolution from microevolution is implied for these taxa.

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