Relaxation of a steep density gradient in a simple fluid: comparison between atomistic and continuum modeling

We compare dynamical nonequilibrium molecular dynamics and continuum simulations of the dynamics of relaxation of a fluid system characterized by a non uniform density profile. Results match quite well as long as the lengthscale of density nonuniformities are greater than the molecular scale (10 times the molecular size). In presence of molecular scale features some of the continuum fields (e.g. density and momentum) are in good agreement with atomistic counterparts, but are smoother. On the contrary, other fields, such at the temperature field, present very large difference with respect to reference (atomistic) ones. This is due to the limited accuracy of some of the empirical relations used in continuum models, the equation of state of the fluid in the example considered

The Feasibility of Productivity Improvement Using the Approach of Virtual Economy

Given the crucial role of e-commerce to create knowledge-based economy, it can be called the most important context to enter the virtual economy. Increasing growth of e-commerce in developed countries and its competitive advantages as well as its important role in employment and production growth in the countries indicate that those countries have revised their current trade policies. The primary goal of this study is to investigate the relationship between productivity improvement and virtual economy. For hypotheses test, Pearson correlation coefficient and SPSS software were used. Summary and conclusion of research hypotheses suggest that there is a significant relationship between improving productivity and virtual economy, so all research hypothesis are confirmed. Keywords: productivity improvement, virtual economy, e-commerce, Pearson correlation coefficient. JEL Classifications: L81, O

Books’ Rating Prediction Using Just Neural Network

Abstract: The aim behind analyzing the Goodreads dataset is to get a fair idea about the relationships between the multiple attributes a book might have, such as: the aggregate rating of each book, the trend of the authors over the years and books with numerous languages. With over a hundred thousand ratings, there are books which just tend to become popular as each day seems to pass. We proposed an Artificial Neural Network (ANN) model for predicting the overall rating of books. The prediction is based on these features (bookID, title, authors, isbn, language_code, isbn13, # num_pages, ratings_count, text_reviews_count), which were used as input variables and (average_rating) as output variable for our ANN model. Our model were created, trained, and validated using data set in JNN environment, which its title is “Goodreads-books”. Model evaluation showed that the ANN model is able to predict correctly 99.78% of the validation samples

A framework for assessing cost management system changes: the case of activity-based costing implementation at food industry

An opportunity to investigate the technical and organizational effect of management accounting system changes has appeared with companies' adoption of activity-based costing (ABC). This paper presents an empirical investigation to study the effects of ABC system for case study from food industry in Iran. From this case, the paper develops a framework for assessing ABC implementation and hypotheses about factors that influence implementation. The study detects five cost centers and for each cost center, it determines different cost drivers. The results of our survey has detected that implementation of ABC system not only helps precise allocation of overhead costs but also helps internal management companies for better planning and control of production, making better decisions for company's profits