Degenerate parabolic partial differential equations (PDEs) with vanishing or unbounded leading coefficient make the PDE non-uniformly parabolic, and new theories need to be developed in the context of practical applications of such rather unstudied mathematical models arising in porous media, population dynamics, financial mathematics, etc. With this new challenge in mind, this paper considers investigating newly formulated direct and inverse problems associated with non-uniform parabolic PDEs where the leading space- and time-dependent coefficient is allowed to vanish on a non-empty, but zero measure, kernel set. In the context of inverse analysis, we consider the linear but ill-posed identification of a space-dependent source from a time-integral observation of the weighted main dependent variable. For both, this inverse source problem as well as its corresponding direct formulation, we rigorously investigate the question of well-posedness. We also give examples of inverse problems for which sufficient conditions guaranteeing the unique solvability are fulfilled, and present the results of numerical simulations. It is hoped that the analysis initiated in this study will open up new avenues for research in the field of direct and inverse problems for degenerate parabolic equations with applications.
The purpose of this study is to investigate learners' listening comprehension problems with Englishlectures. The study was guided by research question (What are the listening comprehension problems learners have with lectures in English).Furthermore; the main significant goal were declared through conducting this study, as well as providing some procedures of distribution the questionnaire of the study.Moreover, it presents several definitions of listening. This study definitely depends on questionnaire instrument to gathering the required data. The participants of the study were 30 learners completed their secondary school and joined at the college. Based on the findings among the five factors (text, speaker, task, environment, and list
... Show MoreThe research aims at:
- Identifying the problems facing kindergarten teachers.
- Identifying the nature of the problems facing kindergarten teachers.
To achieve the aim of the research, the researcher prepared a questionnaire to identify the problems that face the teachers of kindergartens. The questionnaire was subjected to the consultation of a group of specialized expertise in the educational and psychological sciences to certify the propriety of the items of the questionnaire and it gained a rate of (80%), and the stability of the scale gained (0.91) and it stands for a correlation parameter with a statistical significance and it was calculated by using Person’s R Corre
... Show MoreThere Are Many Communities Suffering Of Unemployment Due To Has Great Social And Economic Impact, As Well As The Psychological Effects Devastating And Serious And That May Threaten States With Collapse And Leading Human Displacement And Loss And Crime, And Often Derive Unemployed People To Practice Bad Habits Such As Gambling, Alcohol And Drug Abuse To Escape From Their Reality To Their Concerns And Problems.
It Should Be Noted, That The Largest Percentage Of Unemployment In Developing Societies Represented By The Educated Class Of University Graduates, And This Is Something Painful.
The Unemployed Know That (Each Capable Of Working And Who Want To Look For And Accept Prevailing Bricks) Is Th
... Show MoreObjective: The study objectives are to identify the problems which confront renal transplant recipients
( RTRS).
Methodology: A descriptive study was carried out at two Teaching Hospitals with kidney transplant
centers. Surgical specialties and Al-Karama outpatients,
clinics for ( RTRS) ,and three Teaching
Hospitals; Medical city, Al-Karama and Al-Yermok which were responsible for immunosuppressive
drugs distribution .Starting from October ,1st
2006 to the end of July 2007.To achieve the objectives
of study, a non-probability (purposive) sample of 150 ( RTRS) who were attending to the outpatient
clinic of the above listed hospital were selected according to the criteria of the study sample .
The finalized q
An approximate solution of the liner system of ntegral cquations fot both fredholm(SFIEs)and Volterra(SIES)types has been derived using taylor series expansion.The solusion is essentailly
In this paper, the effect size measures was discussed, which are useful in many estimation processes for direct effect and its relation with indirect and total effects. In addition, an algorithm to calculate the suggested measure of effect size was suggested that represent the ratio of direct effect to the effect of the estimated parameter using the Regression equation of the dependent variable on the mediator variable without using the independent variable in the model. Where this an algorithm clear the possibility to use this regression equation in Mediation Analysis, where usually used the Mediator and independent variable together when the dependent variable regresses on them. Also this an algorithm to show how effect of the
... Show MoreIn this paper a stirred-bed performed of the copper catalyzed synthesis of ethylchlorosilanes from silicon and ethyl chloride was described. A Si-catalyst mixture prepared by reaction of CuCl and Si was employed. The compositions of products were mainly ethyltrichlorosilane, diethyldichlorosilane, and ethyldichlorosilane and mainly depended on the extent of Cu in the mixture and the reaction temperature. A promoting effect on the extent of adsorption was observed on the addition of certain additives. The kinetic data revealed the direct depended of the reaction rate on C2H5Cl pressure.