A General Theory for Analysis of Catch and Effort Data

1985 ◽  
Vol 42 (3) ◽  
pp. 414-429 ◽  
Author(s):  
Jon Schnute
Keyword(s):  
General Theory ◽  
Model Identification ◽  
Identification Problem ◽  
Mathematical Proofs ◽  
Structured Population ◽  
Analysis Technique ◽  
Special Cases ◽  
Age Structured ◽  
Almost All ◽  
Special Case

This paper presents a general theory for analysis of catch and effort data from a fishery. Almost all previous methods are shown to be special cases, including those of Schaefer, Pella and Tomlinson, Schnute, and Deriso, as well as the stock reduction analysis technique of Kimura and Tagart and Kimura, Balsiger, and Ito. Like that of Deriso, the theory here is based on natural equations for an age structured population. However, instead of a fixed single model, this paper gives a general model that can be tailored to any particular fishery. The problem of determining the appropriate special case is conceptually identical to the model identification problem described by Box and Jenkins in the context of time series analysis, Identification necessarily begins with a suitable class of models. This paper defines such a class, unique to fisheries, complete with mathematical proofs and biological explanations of all important equations.

Thermoelastic stresses in initially stressed bodies

1962 ◽  
Vol 266 (1324) ◽  
pp. 1-19 ◽  
Keyword(s):  
Wave Propagation ◽  
General Theory ◽  
Initial Stress ◽  
Elastic Deformation ◽  
Plane Waves ◽  
The Body ◽  
Unstressed State ◽  
Special Cases ◽  
Thermoelastic Stresses ◽  
Special Case

A general theory is presented for small thermoelastic deformations in a body which has already been subjected to an elastic deformation and which was initially aeolotropic. Two special cases are examined in detail. The first is concerned with small thermoelastic deformations in a body which is under initial stress, the state of initial stress not necessarily being obtained by elastic deformation from some other unstressed state. The propagation of plane waves under isothermal or isentropic conditions in such a body is considered when the initial stress is homogeneous. The second special case of the general theory arises when the initial deformation is small and is obtained elastically from an unstressed state of the body. This theory is used to study the torsion of an initially stretched rhombic crystal and wave propagation in homogeneously stressed bodies.

Further developments in a nonlinear theory of water waves for finite and infinite depths

1987 ◽  
Vol 324 (1577) ◽  
pp. 47-72 ◽  
Keyword(s):  
General Theory ◽  
Nonlinear Theory ◽  
Water Waves ◽  
Finite Depth ◽  
Balance Laws ◽  
Jump Conditions ◽  
Infinite Depth ◽  
Inviscid Fluids ◽  
Special Cases ◽  
Special Case

This paper is a companion to an earlier one (Green & Naghdi 1986, Phil. Trans. R. Soc. Lond . A 320, 37-70 (1986)) and deals with certain aspects of a nonlinear waterwave theory and its applications to waters of infinite and finite depths. A new procedure is used to establish a 1-1 correspondence between the lagrangian and eulerian formulations of the integral balance laws of a general thermomechanical theory of directed fluid sheets, as well as their associated jump conditions in the presence of any number of directors. (Such a correspondence between lagrangian and eulerian formulations was previously possible in the special case of a single constrained director.) These results are valid for both compressible and incompressible (not necessarily inviscid) fluids. Applications are then made to special cases of the general theory (including the jump conditions) for incompressible inviscid fluids of infinite depth (with two directors) and of finite depth (with three directors) and the nature of the results are illustrated with particular reference to a wedge-like boat.

scholarly journals ON PROBABILTY DISTRIBUTION IN ASSOCIATION WITH A CERTAIN GENERALIZED HYPERGEOMETRIC FUNCTION

2015 ◽  
Vol 14 (3) ◽  
pp. 5569-5577
Author(s):  
Yashwant Singh ◽  
Nanda Kulkarni
Keyword(s):  
Density Function ◽  
Probability Function ◽  
Special Function ◽  
Special Functions ◽  
Density Functions ◽  
Chi Square ◽  
Recurrence Relationship ◽  
Special Cases ◽  
Almost All ◽  
Special Case

In the present paper, a probability function has been introduced in terms of the -function and its properties are studied. It is shown that the classical non-central distributions such as, non-central chi-square, non-central Student- , non-central and almost all classical central continuous distributions can be obtained as special cases of this general density function. This general density function is introduced with the hope that any density function, which can be represented in terms of any known special function as well as the density of the ratio of any two independent stochastic variables whose density functions can be represented in terms of any known special functions, is contained in as a special case. The properties of , discussed in this paper, include the characteristic function, moments, recurrence relationship among moments and the distribution function.

scholarly journals Aperture referral in dioptric systems with stigmatic elements

2012 ◽  
Vol 71 (1) ◽  
Author(s):  
W. F. Harris
Keyword(s):  
General Theory ◽  
Focal Point ◽  
Positive Zero ◽  
Mathematical Form ◽  
Linear Optics ◽  
Important Special Case ◽  
Vector Algebra ◽  
Special Cases ◽  
Special Case ◽  
Projective Field

A previous paper develops the general theory of aperture referral in linear optics and shows how several ostensibly distinct concepts, including the blur patch on the retina, the effective cornealpatch, the projective field and the field of view, are now unified as particular applications of the general theory.  The theory allows for astigmatism and heterocentricity.  Symplecticity and the generality of the approach, however, make it difficult to gain insight and mean that the material is not accessible to readers unfamiliar with matrices and linear algebra. The purpose of this paper is to examine whatis, perhaps, the most important special case, that in which astigmatism is ignored.  Symplecticity and, hence, the mathematics become greatly simplified. The mathematics reduces largely to elementary vector algebra and, in some places, simple scalar algebra and yet retains the mathematical form of the general approach.  As a result the paper allows insight into and provides a stepping stone to the general theory.  Under referral an aperture under-goes simple scalar magnification and transverse translation.  The paper pays particular attention to referral to transverse planes in the neighbourhood of a focal point where the magnification may be positive, zero or negative.  Circular apertures are treated as special cases of elliptical apertures and the meaning of referred apertures of negative radius is explained briefly. (S Afr Optom 2012 71(1) 3-11)

Extreme self-sacrifice beyond fusion: Moral expansiveness and the special case of allyship

2018 ◽  
Vol 41 ◽  
Author(s):  
Daniel Crimston ◽  
Matthew J. Hornsey
Keyword(s):  
General Theory ◽  
Biological Markers ◽  
Natural Environment ◽  
Relevant Dimension ◽  
Special Case

AbstractAs a general theory of extreme self-sacrifice, Whitehouse's article misses one relevant dimension: people's willingness to fight and die in support of entities not bound by biological markers or ancestral kinship (allyship). We discuss research on moral expansiveness, which highlights individuals’ capacity to self-sacrifice for targets that lie outside traditional in-group markers, including racial out-groups, animals, and the natural environment.

Nonwovens: Global Trends in World Economy, European Foreign Trade, and Selected Case Studies from Poland and Asian Brics Countries

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Zofia Wysokińska ◽  
Tomasz Czajkowski ◽  
Katarzyna Grabowska
Keyword(s):  
Case Studies ◽  
World Economy ◽  
World Market ◽  
Global Trends ◽  
Textile Materials ◽  
Brics Countries ◽  
Recent Trends ◽  
Almost All ◽  
Special Case

AbstractNonwovens are one of the most versatile textile materials and have become increasingly popular in almost all sectors of the economy due to their low manufacturing costs and unique properties. In the next few years, the world market of nonwovens is predicted to grow by 7%–8% annually (International Nonwovens & Disposables Association [INDA], European Disposables and Nonwovens Association [EDANA], and Markets and Markets). This article aims to analyze the most recent trends in the global export and import of nonwovens, to present two case studies of Polish companies that produce them, and to present one special case study of the market of nonwoven geotextiles in China and India, which are the Asian transition economies among the BRICS countries (Brazil, Russia, India, China, and South Africa).

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