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Gompertz Pharmacokinetic Model for Drug Disposition
Pharmaceutical Research, 2002Disposition of drugs among compartments of the body usually occurs at changing rates that are commonly modeled as sums of exponential terms with different rate constants. This paper describes an alternative. Gompertz kinetics, in which the rates can change systematically.Differential equations were developed and solved that fit typical examples taken ...
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Probabilistic Gompertz model of irreversible growth
Bulletin of Mathematical Biology, 2005Characterizing organism growth within populations requires the application of well-studied individual size-at-age models, such as the deterministic Gompertz model, to populations of individuals whose characteristics, corresponding to model parameters, may be highly variable. A natural approach is to assign probability distributions to one or more model
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A stochastic gompertz model with hereditary effect
Journal of Mathematical Biology, 1979In this paper we have studied a stochastic version of the Gompertz model for population growth of a single species after incorporating the aspect of heredity. Various statistical characteristics--the mean-value function, covariance-kernel, etc.--are evaluated for a delta-correlated process and their asymptotic values obtained.
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The modified Gompertz reliability growth model
Proceedings of Annual Reliability and Maintainability Symposium (RAMS), 2002An S-shaped reliability growth curve is used to describe a reliability growth trend with a lower rate of debugging and growth at the early stage and a higher rate later on as better fixes are found and successfully implemented. In some situations, it is unreasonable to set a high growth rate of improvement during the early stages of development for ...
D. Kececioglu +2 more
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A dynamic system for Gompertz model
Journal of Statistical Computation and Simulation, 2017Two-parameter Gompertz distribution has been introduced as a lifetime model for reliability inference recently.
YL Lio +3 more
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Stochastic Gompertz model of tumour cell growth
Journal of Theoretical Biology, 2007In this communication, based upon the deterministic Gompertz law of cell growth, a stochastic model in tumour growth is proposed. This model takes account of both cell fission and mortality too. The corresponding density function of the size of the tumour cells obeys a functional Fokker--Planck equation which can be solved analytically.
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GOMPERTZ Model with Heredity in Random Environment
Biometrical Journal, 1981AbstractIn this paper we investigate the GOMPERTZ model in a randomly varying environment after incorporating the aspect of heredity. Exact expressions for the first two moments of the logarithm of population size are obtained. Special case of the dichotomic MARKOV process being a white noise process is considered.
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Modelling cure rates using the Gompertz model with covariate information
Statistics in Medicine, 1998We extend the modified Gompertz hazard function, first used by Cantor and Shuster for estimation of cure rates from pediatric clinical trials, by including covariate effects. The extended model provides a convenient method for estimation of the cure rate as a function of treatments and covariates.
P W, Gieser +4 more
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The biological foundation of the Gompertz model
International Journal of Bio-Medical Computing, 1987The paper examines the biological reasoning of the Gompertz model for tumor growth: the increase and loss rates of the tumor volume are both proportional to the volume itself. The statement is proved mathematically. The theoretical foundation is therefore established, this ensures the application of the Gompertz model as an effective aid for the ...
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Prediction model based on Gompertz function
2009 2nd IEEE International Conference on Broadband Network & Multimedia Technology, 2009A novel prediction model based on Gompertz function and Customer Life Cycle (CLC) is presented in this paper. Firstly, the calling behavior between the inner-net (China Unicom) mobile customers and the outer-net (China Mobile) mobile customers are extracted and analyzed, then fitted a CLC curve by Gompertz function. Furthermore, the different period of
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