Search results for "VARIATION"

A New Simple Function for Combustion and Cyclic Variation Modeling in Supercharged Spark Ignition Engines

2022

Research in the field of Internal Combustion (IC) engines focuses on the drastic reduction of both pollutant and greenhouse gas emissions. A promising alternative to gasoline and diesel fuel is represented by the use of gaseous fuels, above all green hydrogen but also Natural Gas (NG). In previous works, the authors investigated the performance, efficiency, and emissions of a supercharged Spark Ignition (SI) engine fueled with mixtures of gasoline and natural gas; a detailed research involving the combustion process of this kind of fuel mixture has been previously performed and a lot of experimental data have been collected. Combustion modeling is a fundamental tool in the design and optimi…

Person reference as a device for constructing experiences as typical in group therapy.

2008

Sharing one's experiences is a crucial activity in group therapies. In such therapies, groups can be either constituted around one problem or goal common to all the clients, or the group can work as a place in which clients can learn from one another and share experiences whether their individual problems are similar or not. Almost all (psycho) therapy types have a group application, and groups are assumed to be rather efficient in psychological progressing (see, e.g. Corey, 1986; Wootton, 1977). In this article I will concentrate on one type of group therapy, namely the Minnesota model group therapy for addicts, and examine how the clients share experiences and, especially, how they constr…

Non-homogeneous Dirichlet problems with concave-convex reaction

2022

The variational methods are adopted for establishing the existence of at least two nontrivial solutions for a Dirichlet problem driven by a non-homogeneous differential operator of p-Laplacian type. A large class of nonlinear terms is considered, covering the concave-convex case. In particular, two positive solutions to the problem are obtained under a (p -1)-superlinear growth at infinity, provided that a behaviour less than (p -1)-linear of the nonlinear term in a suitable set is requested.

Negationens placering i finska inlärares svenska

1997

Biharmonic obstacle problem: guaranteed and computable error bounds for approximate solutions

2020

The paper is concerned with a free boundary problem generated by the biharmonic operator and an obstacle. The main goal is to deduce a fully guaranteed upper bound of the difference between the exact minimizer u and any function (approximation) from the corresponding energy class (which consists of the functions in $H^2$ satisfying the prescribed boundary conditions and the restrictions stipulated by the obstacle). For this purpose we use the duality method of the calculus of variations and general type error identities earlier derived for a wide class of convex variational problems. By this method, we define a combined primal--dual measure of error. It contains four terms of different natu…

Gradient nonlinear elliptic systems driven by a (p,q)-laplacian operator

2017

In this paper, using variational methods and critical point theorems, we prove the existence of multiple weak solutions for a gradient nonlinear Dirichlet elliptic system driven by a (p, q)-Laplacian operator.

Intron variants of the p53 gene are associated with increased risk for ovarian cancer but not in carriers of BRCA1 or BRCA2 germline mutations

1999

Two biallelic polymorphisms in introns 3 and 6 of the p53 gene were analysed for a possible risk-modifying effect for ovarian cancer. Germline DNA was genotyped from 310 German Caucasian ovarian cancer patients and 364 healthy controls. We also typed 124 affected and 276 unaffected female carriers with known deleterious BRCA1 or BRCA2 germline mutation from high-risk breast-ovarian cancer families. Genotyping was based on PCR and high-resolution gel electrophoresis. German ovarian cancer patients who carried the rare allele of the MspI restriction fragment length polymorphism (RELP) in intron 6 were found to have an overall 1.93-fold increased risk (95% confidence internal (CI) 1.27–2.91) w…

The importance of genetic variation to the risk of Hymenoptera parasitism in bag worm moths (Lepidoptera: Psychidae)

2008

Shape optimization in contact problems : Approximation and numerical realization

1987

The optímal shape design of a two-dimensíonal elastic body on rigid foundatíon is analyzed. The relation between the continuous problem and the díscrete problem achieved by FEM is presented. A numerícal realization together wíth the sensítivity analysís is given. Several numerical examples to illustrate the practícal use of the methods are presented. peerReviewed

Improvement of partition coefficients determination of aroma compounds in food matrices by the phase ratio variation method

2011

The Phase Ratio Variation (PRV) method is a very valuable method commonly used for liquid/vapor partition coefficients data acquisition of aroma compounds. Nevertheless, some limits are linked to this method, especially for volatile compounds. A careful examination of the PRV equation leads us to propose the following expression: 1/Cvap-real =(nliq/n0) x 1/Cvap-ideal = (nliq/n0) x (1/KC0 + (1/Co) b), We performed an examination for two cases of K values (K1=0.001 and K2=0.05), putting forward that a carefully choice of b range values is crucial for reliability of the regression calculation 1/A versus b.