Shear banding of wormlike micelle solution has been studied in the context of constitutive instability of the Johnson-Segalman (JS) model plus Newtonian stress. We have incorporated a higher-order gradient term of the...
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Shear banding of wormlike micelle solution has been studied in the context of constitutive instability of the Johnson-Segalman (JS) model plus Newtonian stress. We have incorporated a higher-order gradient term of the deformation-rate tensor into the JS model for investigating the dynamics of a mechanical interface in shear-banded flow. Two-dimensional modelling of the new model has been carried out by a general Langrangian-Eulerian scheme. Within the unstable region, our results show that the new term plays an important role in selecting steady-state shear stress and the selected stress is independent of the nominal shear rate. The transit period of reaching the steady state can be much longer than the intrinsic relaxation time of the JS fluid. We have verified the experimental evidence on the existence of mechanical metastable regime, over which hysteresis in flow curve might occur. The model captures many features of experimental results on shear banded flow.
The semi-infinite Domb model with volume-dependent bulk exchange interactions J(upsilon) and modified exchange interactions on the free surface J(S)(upsilon) = (1 + DELTA)J(upsilon) is studied through a variational me...
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The semi-infinite Domb model with volume-dependent bulk exchange interactions J(upsilon) and modified exchange interactions on the free surface J(S)(upsilon) = (1 + DELTA)J(upsilon) is studied through a variational method based on the Bogoliubov inequality for the free energy. The phase diagram of global temperature against DELTA is obtained and it is shown that the orders of some transition lines depend on the value of the pressure. It is also shown that the phase diagram is qualitatively rather different from that obtained for systems having constant exchange interactions and first-order bulk behaviour.
For more than 30 years, Bertrand Meyer has taught the computer science field about formal software engineering and object-oriented approaches;he continues do so through his many books, conferences, and Eiffel.
For more than 30 years, Bertrand Meyer has taught the computer science field about formal software engineering and object-oriented approaches;he continues do so through his many books, conferences, and Eiffel.
3D content still is not widely found on the Web. Now, though, several new technologies may widen 3D's presence on the Web by transforming browsers into computing platforms powerful enough to play the content.
3D content still is not widely found on the Web. Now, though, several new technologies may widen 3D's presence on the Web by transforming browsers into computing platforms powerful enough to play the content.
Replicability is a crucial element of good science, particularly so when the subject matter is sensitive and political. Therefore, we welcome close scrutiny of our brief report in the Annals of Epidemiobgy in 2011, \&...
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Replicability is a crucial element of good science, particularly so when the subject matter is sensitive and political. Therefore, we welcome close scrutiny of our brief report in the Annals of Epidemiobgy in 2011, \"Adolescent Marijuana Use from 2002 to 2008: Higher in States with Medical Marijuana Laws, Cause Still Unclear.\" We were glad to see that Harper et al. (1) were able to replicate our results showing that states with medical marijuana laws (MML) showed greater rates of marijuana use among their residents during 2002 to 2008 and that states that passed MML after 2002 already had greater use among their residents before they passed the law. However, we have several concerns with the additional analyses run by Harper et al. and further concerns with the way their results were presented. We summarize our concerns in this commentary.
Software developers are always looking for ways to boost their effectiveness and productivity and perform complex jobs more quickly and easily, particularly as projects have become increasingly large and complex. Prog...
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Software developers are always looking for ways to boost their effectiveness and productivity and perform complex jobs more quickly and easily, particularly as projects have become increasingly large and complex. Programmers want to shed unneeded complexity and outdated methodologies and move to approaches that focus on making programming simpler and faster. With this in mind, many developers are increasingly using dynamic languages such as javascript, Perl, Python, and Ruby. Although software experts disagree on the exact definition, a dynamic language basically enables programs that can change their code and logical structures at runtime, adding variable types, module names, classes, and functions as they are running. These languages frequently are interpreted and generally check typing at runtime
The goal of this project was to describe the relationship between overall occupational stress (OS), categories of stressors, overall job satisfaction (JS), and facets of JS in orthodontics. Canadian orthodontists were...
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The goal of this project was to describe the relationship between overall occupational stress (OS), categories of stressors, overall job satisfaction (JS), and facets of JS in orthodontics. Canadian orthodontists were mailed an anonymous, self-administered survey. The response rate was 51.2% (335 of 654). The survey included a list of 67 potential stressors representing 6 categories, an overall OS score, and a modified version of the Dentists Satisfaction Survey (DSS). The correlation between the overall OS score and the overall JS scale of the DSS was r = -0.392. The overall OS scores were most strongly correlated to satisfaction with personal time (r = -0.385, P < .01) and satisfaction with practice management (r = -0.334, P < .01). Work-related stressors (r = -0.301, P < .01) and income-related stressors (r = -0.268, P < .01) were the categories with the highest correlation to the overall JS scale. Orthodontists reporting low OS had significantly higher satisfaction scores on all sections of the DSS. This difference was greatest in satisfaction with personal time and practice management. The results indicate the importance of OS in determining JS in orthodontics.
We present Vamonos: a new framework for algorithm visualization, designed from the beginning to support embedding, interaction, and unlimited scope. Visualizations are executed entirely client-side on any device that ...
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ISBN:
(纸本)9781479984541
We present Vamonos: a new framework for algorithm visualization, designed from the beginning to support embedding, interaction, and unlimited scope. Visualizations are executed entirely client-side on any device that supports a modern web browser;they can be embedded into any website or online textbook. Users can specify breakpoints, watched variables, provide inputs to the algorithm (e.g., by drawing a graph using a mouse), and be prompted for interaction by the visualization. The core framework supports any algorithms and data structures that can be implemented in javascript. We have implemented a wide range of visualizations of advanced algorithms topics, including dynamic programming and graph algorithms (e.g., spanning tree, max-flow, bipartite matching algorithms).
Jackson and Sax (JS,) provided a conceptual framework to analyze biodiversity dynamics after environmental change. They discuss transients caused by lags in extinction and immigration, rightly seen as of major importa...
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Jackson and Sax (JS,) provided a conceptual framework to analyze biodiversity dynamics after environmental change. They discuss transients caused by lags in extinction and immigration, rightly seen as of major importance for the future of biodiversity. Borrowing terms from accountancy, they discuss concepts such as \"extinction debts\", \"immigration credits\", \"biodiversity surpluses\" and \"biodiversity deficits\". For example, when time scales of immigration and extinction differ, temporary biodiversity surpluses or deficits may arise. Accidentally, JS overlooked my earlier work covering much of the same ground. This work also corroborates, and adds to, the mainly conceptually oriented approach of JS by using an explicit evolution-based mechanistic model. Thereby it fulfills some of their expressed needs for further research and helps with the understanding and prediction of the kinds of transient dynamics JS discuss.
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