Use of degree of disequilibrium analysis to select kinetic constraints for the rate-controlled constrained-equilibrium (RCCE) method

The Rate-Controlled Constrained-Equilibrium (RCCE) method provides a general framework that enables, with the same ease, reduced order kinetic modelling at three different levels of approximation: shifting equilibrium, frozen equilibrium, as well as non-equilibrium chemical kinetics. The method in general requires a significantly smaller number of differential equations than the dimension of the underlying Detailed Kinetic Model (DKM) for acceptable accuracies. To provide accurate approximations, however, the method requires accurate identification of the bottleneck kinetic mechanisms responsible for slowing down the relaxation of the state of the system towards local chemical equilibrium. In other words, the method requires that such bottleneck mechanisms be characterized by means of a set of representative constraints. So far, a drawback of the RCCE method has been the absence of a systematic algorithm that would allow a fully automatable identification of the best constraints for a given range of thermodynamic conditions and a required level of approximation. In this paper, we provide the first of two steps towards such algorithm based on the analysis of the degrees of disequilibrium (DoD) of chemical reactions in the underlying DKM. In any given DKM the number of rate-limiting kinetic bottlenecks is generally much smaller than the number of species in the model. As a result, the DoDs of all the chemical reactions effectively assemble into a small number of groups that bear the information of the rate-controlling constraints. The DoDs of all reactions in each group exhibit almost identical behaviour (time evolution, spatial dependence). Upon identification of these groups, the proposed kernel analysis of N matrices that are obtained from the stoichiometric coefficients yields the N constraints that effectively control the dynamics of the system. The method is demonstrated within the framework of modeling the expansion of products of the oxy-combustion of hydrogen through a quasi one-dimensional supersonic nozzle. The analysis predicts and RCCE simulations confirm that, under the geometrical and boundary conditions considered, the underlying DKM is accurately represented by only two bottleneck kinetic mechanisms, instead of the three constraints identified for the same problem in a recently published work also based, in part, on DoD analysis

Treatment of Migraine: How Effective Is Biofeedback Assisted Relaxation Training?

ObjectiveBehavioral interventions such as relaxation training and biofeedback are some of the most effective interventions for management of migraine headaches. In this study we evaluated the utility of biofeedback-assisted progressive muscle relaxation training (PRT) in the treatment of migraine.Materials and MethodsIn this prospective study, twenty patients (12-18 years old) with a confirmed diagnosis of migraine headache, admitted to the Talie counseling center between March 2005 and December 2005, were evaluated; they were randomly assigned into an experimental group receiving biofeedback-assisted PRT and a control group in waiting list. All patients recorded the intensity of the headache and its frequency and duration before and 12 weeks after the treatment.ResultsThe data was analyzed using Independent sample t-test for mean differences.In the biofeedback-assisted progressive muscle relaxation trained group, a statistically and clinically significant decrease was detected in intensity (pConclusionIt can be concluded that biofeedback-assisted progressive muscle relaxation training is a successful form of therapy in treatment of migraine

A Study of the Relationship Between Seystem of parents Values and interests and Self-Esteem of Students

The Value Systems and self-Esteem are two factors of mental and social health. This research aimed to investigate the relationship between parents value and interests and Self-Esteem of students. 212 male and female adolescents were tested by Coopersmit self-Esteem Inventory (SEI) and 212 parents of the same students were tested based on Alport, Venon and Lindzey. Analysis of data (Pearson’s correlation, Regression analysis ) demonstrates a significant correlation between some of the dimentions of parents value interests (Just Mothers) and Student’s self-Esteem. Social intrest values of mothers were negatively correlated with Studen’s self-Esteem. Effects of value interests of parent on student's Self-Esteem were different

Entropy transport equation in large eddy simulation for exergy analysis of turbulent combustion systems

The transport equation of entropy is introduced in large eddy simulation to perform exergy analysis of turbulent combustion systems. The sources of exergy destruction can be evaluated by analyzing entropy generation terms, which appear in unclosed forms in this equation. The closure is based on the filtered density function (FDF) methodology. The primary advantage of FDF is that chemical reaction and its entropy generation effects appear in closed forms. This methodology involves a stochastic model, which is being developed to account for the subgrid scale transport of entropy

Systematic constraint selection strategy for rate-controlled constrained-equilibrium modeling of complex nonequilibrium chemical kinetics

Rate-Controlled Constrained-Equilibrium (RCCE) modeling of complex chemical kinetics provides acceptable accuracies with much fewer differential equations than for the fully Detailed Kinetic Model (DKM). Since its introduction by James C. Keck, a drawback of the RCCE scheme has been the absence of an automatable, systematic procedure to identify the constraints that most effectively warrant a desired level of approximation for a given range of initial, boundary, and thermodynamic conditions. An optimal constraint identification has been recently proposed. Given a DKM with S species, E elements, and R reactions, the procedure starts by running a probe DKM simulation to compute an S-vector that we call overall degree of disequilibrium (ODoD) because its scalar product with the S-vector formed by the stoichiometric coefficients of any reaction yields its degree of disequilibrium (DoD). The ODoD vector evolves in the same (S-E)-dimensional stoichiometric subspace spanned by the R stoichiometric S-vectors. Next we construct the rank-(S-E) matrix of ODoD traces obtained from the probe DKM numerical simulation and compute its singular value decomposition (SVD). By retaining only the first C largest singular values of the SVD and setting to zero all the others we obtain the best rank-C approximation of the matrix of ODoD traces whereby its columns span a C-dimensional subspace of the stoichiometric subspace. This in turn yields the best approximation of the evolution of the ODoD vector in terms of only C parameters that we call the constraint potentials. The resulting order-C RCCE approximate model reduces the number of independent differential equations related to species, mass, and energy balances from S+2 to C+E+2, with substantial computational savings when C ≪ S-E

Virtual in-service training from the librarians' point of view in libraries of medical sciences universities in Tehran

Background: In-service training courses are one of the most available programs that are used to improve the quantity and quality level of the staff services in various organizations, including libraries and information centers. With the advent of new technologies in the field of education, the problems and shortcomings of traditional in-service training courses were replaced with virtual ones. This study aimed to evaluate the virtual in-service training courses from the librarians' point of view in libraries of state universities of medical sciences in Tehran. Methods: This was a descriptive- analytical study. The statistical population consisted of all librarians at libraries of universities of medical sciences in Tehran. Out of 103 librarians working in the libraries under the study, 93 (90) participated in this study. Data were collected, using a questionnaire. Results: The results revealed that 94/6 of librarians were satisfied to participate in virtual in-service training courses. In this study, only 45 out of 93 participants said that the virtual in-service courses were held in their libraries. Of the participants, 75.6 were satisfied with the length of training courses, and one month seemed to be adequate time duration for the librarians to be more satisfied. The satisfaction level of the individuals who participated in in-service courses of the National Library was moderate to high. A total of 84.4 participants announced that the productivity level of the training courses was moderate to high. The most important problem with which the librarians were confronted in virtual in-service training was the "low speed of the internet and inadequate computer substructures". Conclusion: Effectiveness of in-service training courses from librarians' point of view was at an optimal level in the studied libraries

Comparison of Therapy Based on Prob-lem-solving Skills and Confronting with Weight Management Therapy Cognition in Body Mass Index (BMI) Reduction and Improvement of Weight Efficient Lifestyl

Having inefficient lifestyle, incorrect dietary habits, low body exercise, and social-cultural environment malfunction are main factors for over-weighting and fatness. So this survey tries to compare efficiency of two methods of therapy based on problem-solving skills and weight man-agement therapy cognition in BMI reduction and improvement of weight efficiency lifestyle among overweight and fat women. For this purpose, 34 women with BMI˃ 25 were selected by available sampling and were categorized in two test groups of therapy based on problem-solving, and confronting with and cognition of therapy (each group 17 persons). All of tested women answered to WEL questionnaire items at the beginning, at the end, and 12 weeks after each therapy course finish and their BMI was calculated. Data analysis through SPSS 16th version and by applying frequent-measurement variance analysis test showed that two interven-tions have led to meaningful reduction of BMI (P˂0.05). But no mea-ningful difference was observed between these two interventions in this area (P˃0.05). Also, there was no significant difference between the two interventions on improvement of weight efficiency lifestyle (P˃0.05). Therefore, it could be concluded that using special methods of each in-tervention such as self-supervision, correction of destructive thought, problem-solving skills, and strategies against environmental and emo-tional clues for triggering of eating, subjects could increase self-inhibition and resistance against these stimuli and help to improve their weight efficient lifestyle and their weight loosing