Twin Concordance. A More General Model

1979 ◽  
Vol 28 (1) ◽  
pp. 3-13 ◽  
Author(s):  
G. Allen ◽  
Z. Hrubec
Keyword(s):  
Mathematical Model ◽  
General Model ◽  
Population Sample ◽  
Concordance Rate ◽  
Continuous Variation ◽  
Measures Of Concordance ◽  
Two Stages ◽  
Second Twin

Estimation of the twin concordance rate for a disease often requires two stages. First, the disease is ascertained in a population or in a population sample, and such twins as are found with the disease become probands. Second, twin pairs with only one proband are further investigated and additional concordant pairs are thus discovered. A mathematical model is presented that allows for continuous variation in completeness of ascertainment in both stages, for correlation within pairs in the primary ascertainment process, and for correlation within pairs in occurrence of the disease. The concordance rate can be estimated by the proband method if secondary ascertainment is complete; other measures of concordance are accurate only if primary ascertainment is complete. A parameter analogous to the concordance rate but related to correlation in primary ascertainment can be estimated from the same data.

A High Performance Model for Task Allocation in Distributed Computing System Using K-Means Clustering Technique

2018 ◽  
Vol 9 (3) ◽  
pp. 1-23 ◽  
Author(s):  
Harendra Kumar ◽  
Nutan Kumari Chauhan ◽  
Pradeep Kumar Yadav
Keyword(s):  
Mathematical Model ◽  
Distributed Computing ◽  
High Performance ◽  
Computing System ◽  
Performance Model ◽  
Communication Costs ◽  
Clustering Technique ◽  
Proposed Model ◽  
Two Stages ◽  
The Mathematical Model

Tasks allocation is an important step for obtaining high performance in distributed computing system (DCS). This article attempts to develop a mathematical model for allocating the tasks to the processors in order to achieve optimal cost and optimal reliability of the system. The proposed model has been divided into two stages. Stage-I, makes the ‘n' clusters of set of ‘m' tasks by using k-means clustering technique. To use the k-means clustering techniques, the inter-task communication costs have been modified in such a way that highly communicated tasks are clustered together to minimize the communication costs between tasks. Stage-II, allocates the ‘n' clusters of tasks onto ‘n' processors to minimize the system cost. To design the mathematical model, executions costs and inter tasks communication costs have been taken in the form of matrices. To test the performance of the proposed model, many examples are considered from different research papers and results of examples have compared with some existing models.

Mathematical Description of Interaction of the Elements in the Power Network System

2013 ◽  
Vol 448-453 ◽  
pp. 2455-2460 ◽  
Author(s):  
Marina N. Dubyago
Keyword(s):  
Mathematical Model ◽  
Power Systems ◽  
Mathematical Description ◽  
Synchronous Generator ◽  
Network System ◽  
Power Network ◽  
Analysis Of Stability ◽  
A Site ◽  
Two Stages

Research of stability of the power systems (PS) assumes the analysis of stability static or dynamic both generators, and engines. This article represents creations of the PS mathematical model is considered as sequence of two stages: creation of models of separate elements; creation of model of their interaction. The mathematical description of a site of distributive system on the example of the synchronous generator.

scholarly journals Assessment of the Efficient Strategies for Applying Antitumor Viral Vaccine Therapy Based On Mathematical Modeling

2019 ◽  
Vol 14 (1) ◽  
pp. 34-53 ◽  
Author(s):  
N.A. Babushkina ◽  
E.A. Kuzina ◽  
A.A. Loos ◽  
E.V. Belyaeva
Keyword(s):  
Mathematical Model ◽  
Immune Response ◽  
Tumor Cells ◽  
Tumor Size ◽  
Single Shot ◽  
Complete Elimination ◽  
Antitumor Therapy ◽  
Viral Vaccine ◽  
Two Stages ◽  
The Mathematical Model

The paper presents the mathematical description of the two stages of tumor cells’ death as a result of immune response after antitumor viral vaccine introduction. This mathematical description is presented by the system of nonlinear equations implemented in the MatLab-Simulink system. As a result of the computing experiment, two strategies for effective application of the antitumor viral vaccine were identified. The first strategy leads to complete elimination of the tumor cells after a single-shot administration of the vaccine. The second strategy makes it possible to stabilize tumor size through the recurrent introductions of the vaccine. Using the mathematical model of antitumor therapy, appropriate dosages were identified based on the number of tumor cells that die at the two stages of immune response. Dynamics of tumor growth for the two strategies of the viral vaccine application was forecasted based on the mathematical model of antitumor therapy with discontinuous trajectories of tumor growth. The computing experiments made it possible to identify initial tumor size at the start of the therapy and the dosages that allow complete elimination of the tumor cells after the single-shot introduction. For the second strategy, dosages and intervals between recurrent vaccine introductions required to stabilize tumor size at the initial level were also identified. The proposed approach to exploring the effectiveness of vaccine therapy may be applied to different types of experimental tumors and antitumor vaccines.

scholarly journals Uptake of cadmium by Pseudokirchneriella supcapitata

2005 ◽  
Vol 48 (6) ◽  
pp. 1027-1034 ◽  
Author(s):  
Magela Paula Casiraghi ◽  
Samuel Luporini ◽  
Eduardo Mendes da Silva
Keyword(s):  
Mathematical Model ◽  
Metal Ions ◽  
Simulation Model ◽  
Kinetic Parameters ◽  
Cellular Membrane ◽  
Surface Absorption ◽  
Fast Absorption ◽  
Passive Adsorption ◽  
Two Stages ◽  
The Mathematical Model

In this work the microalgae Pseudokirchneriella supcapitata was used for the removal of the cadmium in liquids. The accumulations of metal ions by the alga occur in two stages: a very fast absorption (passive adsorption) proceeded by a slower absorption (activate absorption). A mathematical model based on the surface absorption and on the transport into the interior of the cellular membrane was developed. The simulation model kinetic parameters were experimentally obtained. Through the results observed, the mathematical model was shown to be suitable when compared to the experimental results, confirming the validation of the mathematical model.

Dynamic mathematical model of high rate algal ponds (HRAP)

2003 ◽  
Vol 48 (2) ◽  
pp. 197-204 ◽  
Author(s):  
H. Jupsin ◽  
E. Praet ◽  
J.-L. Vasel
Keyword(s):  
Mathematical Model ◽  
High Rate ◽  
State Variables ◽  
Aerobic Growth ◽  
Quality Model ◽  
High Rate Algal Ponds ◽  
Advection Term ◽  
In Series ◽  
Two Stages ◽  
Reactor Cross Section

This article presents a mathematical model to describe High-Rate Algal Ponds (HRAPs). The hydrodynamic behavior of the reactor is described as completely mixed tanks in series with recirculation. The hydrodynamic pattern is combined with a subset of River Water Quality Model 1 (RWQM1), including the main processes in liquid phase. Our aim is to develop models for WSPs and aerated lagoons, too, but we focused on HRAPs first for several reasons:• Sediments are usually less abundant in HRAP and can be neglected• Stratification is not observed and state variables are constant in a reactor cross section• Due to the system's geometry, the reactor is quite similar to a plugflow type reactor with recirculation, with a simple advection term. The model is based on mass balances and includes the following processes:Phytoplankton growth with NO3-, NO2- and death• Aerobic growth of heterotrophs with NO3-, NH4+ and respiration• Anoxic growth of heterotrophs with NO3-, NO2- and anoxic respiration• Growth of nitrifiers (two stages) and respiration. The differences with regard to RWQM1 are that we included a limiting term associated with inorganic carbon on the growth rate of algae and nitrifiers, gas transfers are taken into account by the familiar Adeney equation, and a subroutine calculates light intensity at the water surface. This article presents our first simulations.

scholarly journals How truth wins in opinion dynamics along issue sequences

2017 ◽  
Vol 114 (43) ◽  
pp. 11380-11385 ◽  
Author(s):  
Noah E. Friedkin ◽  
Francesco Bullo
Keyword(s):  
Mathematical Model ◽  
Open Problem ◽  
General Model ◽  
Network Science ◽  
Social Groups ◽  
Opinion Dynamics ◽  
Interpersonal Influence ◽  
Important Open Problem

How truth wins in social groups is an important open problem. Classic experiments on social groups dealing with truth statement issues present mixed findings on the conditions of truth abandonment and reaching a consensus on the truth. No theory has been developed and evaluated that might integrate these findings with a mathematical model of the interpersonal influence system that alters some or all of its members’ positions on an issue. In this paper we provide evidence that a general model in the network science on opinion dynamics substantially clarifies how truth wins in groups.

scholarly journals Efficiency evaluation of energy recovery in the bunk of a timber truck based on the results of simulation modelling

2021 ◽  
Vol 875 (1) ◽  
pp. 012030
Author(s):  
V I Posmetev ◽  
V O Nikonov ◽  
V V Posmetev
Keyword(s):  
Mathematical Model ◽  
Computer Program ◽  
Energy Recovery ◽  
Hydraulic Cylinder ◽  
Simulation Modelling ◽  
Efficiency Evaluation ◽  
Preliminary Assessment ◽  
Promising Direction ◽  
Second Stage ◽  
Two Stages

Abstract The main reasons restraining the efficiency of timber trucks (hauling tractors with semi-trailers) have been considered. A promising direction has been proposed making it possible to increase the efficiency of hauling tractors with semi-trailers. This direction consists in the development and study of a recuperative bunk device for a timber haulage site, installed on a logging tractor. The aim of the research consisted of two stages. At the first stage, a mathematical model for the functioning of the recuperative bunk device of the logging site, installed on a timber truck has been developed. At the second stage, a computer program for a preliminary assessment of the efficiency of the proposed recuperative system has been created. The time dependence of the current recuperative power when hauling tractor moves along an insufficiently equipped timber road has been obtained. The regularity of the influence of the diameter of the hydraulic cylinder of the recuperative bunk device on the average values of the recovered power has been revealed.

scholarly journals Approximation of weak solution for the problem of a pH-gradient creation in isoelectrofocusing

2014 ◽  
Vol 470 (2171) ◽  
pp. 20140290
Author(s):  
L. V. Sakharova ◽  
E. V. Shiryaeva ◽  
M. Yu. Zhukov
Keyword(s):  
Mathematical Model ◽  
Aqueous Solution ◽  
Weak Solution ◽  
Differential Equations ◽  
Electric Field ◽  
Small Parameter ◽  
General Model ◽  
Smooth Functions ◽  
Piecewise Continuous ◽  
The Mathematical Model

The mathematical model describing the stationary natural pH -gradient arising under the action of an electric field in an aqueous solution of ampholytes is constructed and investigated. The model is a part of a more general model of the isoelectrofocusing process. Investigation is based on the approximation of a weak solution by the piecewise continuous non-smooth functions. The method can be used for solving classes of problems for ordinary differential equations with a small parameter at the highest derivatives and the turning points.

A mathematical model describing the two stages of low-pressure-vaporization of free water

2012 ◽  
Vol 112 (4) ◽  
pp. 274-281 ◽  
Author(s):  
C.M. Augusto ◽  
J.B. Ribeiro ◽  
A.R. Gaspar ◽  
V.R. Ferreira ◽  
J.J. Costa
Keyword(s):  
Mathematical Model ◽  
Free Water ◽  
Low Pressure ◽  
Two Stages
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