scholarly journals How to make a kin selection model when marginal fitness is non-linear?

2014 ◽  
Author(s):  
Roberto H. Schonmann ◽  
Robert Boyd ◽  
Renato Vicente
Keyword(s):  
Linear Function ◽  
Social Environment ◽  
Kin Selection ◽  
Mutant Allele ◽  
Nonlinear Function ◽  
Selection Model ◽  
Fitness Functions ◽  
Non Linear ◽  
Monomorphic Population ◽  
Function Of Two Variables

We observe that the Taylor-Frank method for making kin selection models when fitness $w$ is a nonlinear function of a continuous actor's phenotype $y$ and the average phenotype $z$ in its social environment requires $w(y,z)$ to be differentiable (as a function of two variables, i.e., jointly in $y$ and $z$). This means that even if $w(y,z)$ is non-linear globally, locally it must be close to linear, meaning that its graph must be well approximated by a plane. When more than two individuals interact, this assumption is only satisfied when the marginal fitness of the actor is a linear function of the fraction of individuals in its social environment that share its phenotype. This assumption sometimes fails for biologically important fitness functions, for instance in microbial data and the theory of repeated n-person games. In these cases, the Taylor-Frank methodology cannot be used, and a more general form of direct fitness must replace it, to decide when a social mutant allele can invade a monomorphic population.

scholarly journals NON LINEAR FEEDBACK STREAM CIPHER

2012 ◽  
pp. 132-138
Author(s):  
Dr .R. Siva Ram Prasad ◽  
G. Murali ◽  
S. Gopi Krishna
Keyword(s):  
Linear Function ◽  
Stream Cipher ◽  
Nonlinear Function ◽  
Linear Feedback ◽  
Synchronous Mode ◽  
Plain Text ◽  
Cipher Text ◽  
Security Software ◽  
Non Linear ◽  
New Generation

The main aim of this paper is to develop a new generation and innovative security software for applications. We proposed new stream cipher called NLFS. NLFS means Non-linear feedback stream cipher, which is a fast and secure stream cipher for egovernance applications. This stream cipher uses AES secure non-linear function and AES key generation. NLFS uses primitive polynomial generated S-boxes in byte substitution step. NLFS uses two similar AES round functions and these two proceed parallelly to produce key-stream. Non-linear *function of NLFS has AES nonlinear function steps (add-round key, byte substitution, mix column, shift rows) and it extra includes value-based rotation step. In value based rotation step it rotates each 8-bit word by its first 3-bit (decimal) value.NLFS have two modes basic mode that is synchronous mode and self synchronous mode. In synchronous mode key stream is independent of plain text and cipher text. In selfsynchronous mode key stream generation depending on cipher text. In self synchronous mode generated keystream update first 512-bit buffer and cipher text update the second buffer.

CLASS OF BOOLEAN FUNCTIONS CONSTRUCTED USING SIGNIFICANT BITS OF LINEAR RECURRENCES OVER THE RING ℤ2n

2019 ◽  
Vol 6 (2) ◽  
pp. 90-94
Author(s):  
Hernandez Piloto Daniel Humberto
Keyword(s):  
Linear Function ◽  
Boolean Functions ◽  
Hamming Distance ◽  
Linear Recurrences ◽  
Maximum Period ◽  
Non Linear ◽  
The Given ◽  
Class Of Functions

In this work a class of functions is studied, which are built with the help of significant bits sequences on the ring ℤ2n. This class is built with use of a function ψ: ℤ2n → ℤ2. In public literature there are works in which ψ is a linear function. Here we will use a non-linear ψ function for this set. It is known that the period of a polynomial F in the ring ℤ2n is equal to T(mod 2)2α, where α∈ , n01- . The polynomials for which it is true that T(F) = T(F mod 2), in other words α = 0, are called marked polynomials. For our class we are going to use a polynomial with a maximum period as the characteristic polyomial. In the present work we show the bounds of the given class: non-linearity, the weight of the functions, the Hamming distance between functions. The Hamming distance between these functions and functions of other known classes is also given.

scholarly journals Non-Linear Effects of the Built Environment and Social Environment on Bus Use among Older Adults in China: An Application of the XGBoost Model

2021 ◽  
Vol 18 (18) ◽  
pp. 9592
Author(s):  
Lanjing Wang ◽  
Chunli Zhao ◽  
Xiaofei Liu ◽  
Xumei Chen ◽  
Chaoyang Li ◽  
...  
Keyword(s):  
Older Adults ◽  
Land Use ◽  
Built Environment ◽  
Social Environment ◽  
Public Transport ◽  
Dwelling Unit ◽  
Bus Stop ◽  
Environment Variable ◽  
Non Linear ◽  
Unit Density

Global aging has raised increasing concerns on the health and well-being of older adults. Public transport is a viable option to improve the mobility and quality of life among older adults. However, policies that promote the public transport use among older adults are rare. This study utilizes the eXtreme Gradient Boosting (XGBoost) decision tree to explore the non-linear associations of the built and social environment with bus use among older adults in China. The bus use of older adults was obtained from the Zhongshan Household Travel Survey (ZHTS) in 2012. Results show that non-linear relationships exist among all built environment and social environment characteristics. Within certain thresholds, the percentage of green space land use, land use mixture, bus-stop density, and dwelling unit density are positively related to bus use among older adults. Likewise, one social environment variable, the proportion of older adults in a neighborhood, is the key social environment variable. Furthermore, the dwelling unit density and proportion of older adults appear to have an inverse U-shaped relationship. Additionally, age, ownership of motorcycles, and distance from home to the nearest bus stop also show non-linearity. The findings presented in this paper facilitate effective planning interventions to promote bus use among older adults.

Non-Linear PID Controller Parameter Optimization of Vertical Take-Off and Landing Stage for Tilt Rotor Aircraft

2014 ◽  
Vol 1082 ◽  
pp. 525-528
Author(s):  
Yuan Qi Zhang ◽  
Wei Ping Zhao ◽  
Song Xiang
Keyword(s):  
Parameter Optimization ◽  
Pid Controller ◽  
Angular Position ◽  
Nonlinear Function ◽  
Stability Control ◽  
Loop Control ◽  
Controller Parameter ◽  
Tilt Rotor ◽  
Non Linear ◽  
Aircraft System

Proportion, integration and differential gain of nonlinear PID Controller is nonlinear function of controlling error. This paper performed the non-linear PID controller parameter optimization of vertical take-off and landing stage for tilt rotor aircraft using the genetic algorithm. Dual loop control is used. Inner loop is angular velocity loop. Outer loop is angular position loop. According to the features of stability control of vertical take-off and landing stage of tilt rotor aircraft, system ascend time, steady error, and weighted overshoot are chosen as objective function of optimization. Simulation results show that controller designed by the present method can meet the requirement of control.

Apparent octanol/water partition coefficients of pentachlorophenol as a function of pH

1982 ◽  
Vol 60 (16) ◽  
pp. 2104-2106 ◽  
Author(s):  
Klaus L. E. Kaiser ◽  
Ilze Valdmanis
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Partition Coefficient ◽  
Linear Function ◽  
Partition Coefficients ◽  
Extreme Values ◽  
Log P ◽  
Water Partition Coefficient ◽  
Non Linear ◽  
Good Agreement

The apparent 1-octanol/water partition coefficient (log PApp) of pentachlorophenol (PCP) varies in non-linear function with pH of the aqueous solution. In the range of pH 1.2 to 13.5 extreme values of log PApp 4.84 at pH 1.2 and log PApp 1.3 at pH 10.5 were observed. In the alkaline regime, log PApp increases strongly with the ionic strength. The ion-corrected partition coefficient of PCP was found to be log P 5.05 in good agreement with literature values.

The effect of temperature on times to hatching of eggs of the nematode Ostertagia circumcincta

Parasitology ◽  
1980 ◽  
Vol 81 (3) ◽  
pp. 477-491 ◽  
Author(s):  
R. R. Young ◽  
N. Anderson ◽  
D. Overend ◽  
R. L. Tweedie ◽  
K. W. J. Malafant ◽  
...  
Keyword(s):  
Linear Function ◽  
Gamma Distribution ◽  
Effect Of Temperature ◽  
Non Linear ◽  
The Relationship

SUMMARYA delayed gamma distribution satisfactorily described the distribution of times to hatching of Ostertagia circumcincta eggs incubated in 0·1% saline at temperatures between 6 and 20 °C. Below 6 °C hatching of eggs was extremely variable. The relationship between rates of development and temperature within the range 10 to 20 °C was more closely described by a non-linear function than a linear one. The non-linear function was incorporated into a temperature summation equation which satisfactorily predicted the hatching of eggs incubated under conditions of alternating temperatures.

scholarly journals Exact potential and scattering amplitudes from the tachyon non-linear  -function

2004 ◽  
Vol 2004 (03) ◽  
pp. 030-030 ◽  
Author(s):  
E Coletti ◽  
V Forini ◽  
G Grignani ◽  
G Nardelli ◽  
M Orselli
Keyword(s):  
Scattering Amplitudes ◽  
Linear Function ◽  
Non Linear

scholarly journals Sibling quality and the haplodiploidy hypothesis

2020 ◽  
Vol 16 (3) ◽  
pp. 20190764 ◽  
Author(s):  
P. Kennedy ◽  
A. N. Radford
Keyword(s):  
Sex Ratio ◽  
Kin Selection ◽  
Selection Model ◽  
Male Fitness ◽  
Female Fitness ◽  
Evolution Of Eusociality ◽  
Insect Biology ◽  
Relatedness Asymmetry

The ‘haplodiploidy hypothesis’ argues that haplodiploid inheritance in bees, wasps, and ants generates relatedness asymmetries that promote the evolution of altruism by females, who are less related to their offspring than to their sisters (‘supersister’ relatedness). However, a consensus holds that relatedness asymmetry can only drive the evolution of eusociality if workers can direct their help preferentially to sisters over brothers, either through sex-ratio biases or a pre-existing ability to discriminate sexes among the brood. We show via a kin selection model that a simple feature of insect biology can promote the origin of workers in haplodiploids without requiring either condition. In insects in which females must found and provision new nests, body quality may have a stronger influence on female fitness than on male fitness. If altruism boosts the quality of all larval siblings, sisters may, therefore, benefit more than brothers from receiving the same amount of help. Accordingly, the benefits of altruism would fall disproportionately on supersisters in haplodiploids. Haplodiploid females should be more prone to altruism than diplodiploid females or males of either ploidy when altruism elevates female fitness especially, and even when altruists are blind to sibling sex.

The eleventh R. A. Fisher Memorial Lecture - Kin selection and altruism

1983 ◽  
Vol 219 (1216) ◽  
pp. 327-353 ◽  
Keyword(s):  
Kin Selection ◽  
Group Composition ◽  
Group Structure ◽  
Fitness Function ◽  
Memorial Lecture ◽  
Marginal Benefit ◽  
Fitness Functions ◽  
Short And Long Term ◽  
Cost Parameters

Fisher (1930), Haldane (1932), and others discussed short and long term fitness relationships of the biological basis of social behaviour. Hamilton (1964 a , b ) proposed the inequality b / c > 1/ r ( b and c are marginal benefit and cost parameters, respectively, r is an appropriate kinship coefficient) as an essential concomitant of the evolution of altruism. Virtually all current kin selection models take the marginal benefit and cost parameters as primitive concepts and combine them in various ways to determine population fitness values. We offer an intrinsic ‘fitness function’ approach to modelling the theory of kin selection. The components of the model involve: ( a ) the delineation of the basic group structure specifying individual relationships; ( b ) the specification of local fitness functions that depend on group composition; ( c ) the determination of average fitness functions for the different phenotypes with respect to the population at large. We then derive a pair of benefit and cost functions, which are functions of the group composition and the numbers of altruist and selfish phenotypes. In this new framework the quantitative validity of the Hamilton criterion for the evolution of altruism are assessed and reinterpreted.

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