scholarly journals Nonpremixed Counterflow Flames: Scaling Rules for Batch Simulations

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Thomas Fiala ◽  
Thomas Sattelmayer
Keyword(s):  
Strain Rate ◽  
Test Cases ◽  
Finite Rate ◽  
Convergence Behavior ◽  
Counterflow Flame ◽  
The Creation ◽  
Counterflow Flames ◽  
The Impact ◽  
Extinction Point

A method is presented to significantly improve the convergence behavior of batch nonpremixed counterflow flame simulations with finite-rate chemistry. The method is applicable to simulations with varying pressure or strain rate, as it is, for example, necessary for the creation of flamelet tables or the computation of the extinction point. The improvement is achieved by estimating the solution beforehand. The underlying scaling rules are derived from theory, literature, and empirical observations. The estimate is used as an initialization for the actual solver. This enhancement leads to a significantly improved robustness and acceleration of batch simulations. The extinction point can be simulated without cumbersome code extensions. The method is demonstrated on two test cases and the impact is discussed.

Investigation of unsteady premixed micro/macro counterflow flames for lean to rich methane/air mixture

2020 ◽  
pp. 1-15
Author(s):  
Ali Edalati-nejad ◽  
Sayyed Aboozar Fanaee ◽  
Maryam Ghodrat ◽  
Javad Khadem
Keyword(s):  
Strain Rate ◽  
Flame Structure ◽  
Time Dependent ◽  
Stability Parameters ◽  
Steady State Condition ◽  
Counterflow Flame ◽  
Time Period ◽  
Counterflow Flames ◽  
The Impact ◽  
Time Dependent Analysis

Abstract In the current work, an unsteady analysis of methane/air premixed counterflow flame is carried out for different flame conditions and stability parameters considering different strain rate values. The results are presented at unsteady and final steady conditions and the impact of time-dependent regimes and variations in equivalence ratio, from lean flame to rich one are analysed. The governing equations including continuity, momentum, energy, and species are numerically solved with a coupled of simple and Piso algorithm. It is also found that when the strain rate value is 1000s-1, for flame stability, the hydraulic distance of the microchannel must be at least 0.05mm. Increasing the strain rate results in decreasing the time of stabilizing temperature distribution with a faster quasi-steady equilibrium. The necessity of time dependent analysis is to comprehend the variations in main factors of flame structure before reaching the finalized steady state condition. Therefore, by designing an intermittent automatic valve, if the flow stops in time period of 0.0025s and starts again, the formation of NO2 and CO2 will be reduced about 50% and 9%, respectively, in a case with a=100s-1.

The Combined Effects of Heat Loss and Reversibility on the Propagation of Planar Premixed Counterflow Flames

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Faisal Al-Malki
Keyword(s):  
Activation Energy ◽  
Finite Elements ◽  
Strain Rate ◽  
Heat Loss ◽  
Constant Density ◽  
Combined Effects ◽  
Stability Of Solutions ◽  
Counterflow Flames ◽  
The Stability ◽  
The Impact

Abstract We study in this paper the combined effect of heat loss and reversibility on the propagation of planar flames formed within the counterflow configuration. The problem has been formulated first using the thermodiffusive model with constant density and then solved numerically using finite elements. The impact of four main parameters, namely the reversibility r, the heat loss κ, the strain rate ε, and the activation energy β, on the propagation of planar flames has been discussed in details. The study has shown that planar flames under reversible conditions behave qualitatively similar to those observed for irreversible reactions, which agree with the asymptotic findings. In the presence of heat loss, the problem exhibits multiplicity of solutions whose number and stability were found to vary according to the strain rate ε. In addition, the study has predicted the existence of a certain value of the reversibility parameter r beyond which the impact of reversibility becomes negligible. Finally, we have examined the stability of the solutions and determined the domain of stability of solutions and their multiplicity for this problem.

Trading faces: Complete AI face doubles avoid the uncanny valley

2020 ◽  
Author(s):  
Christopher Welker ◽  
David France ◽  
Alice Henty ◽  
Thalia Wheatley
Keyword(s):  
Artificial Intelligence ◽  
Sexual Orientation ◽  
Uncanny Valley ◽  
Torture Survivors ◽  
The Uncanny ◽  
The Creation ◽  
Full Face ◽  
The Impact

Advances in artificial intelligence (AI) enable the creation of videos in which a person appears to say or do things they did not. The impact of these so-called “deepfakes” hinges on their perceived realness. Here we tested different versions of deepfake faces for Welcome to Chechnya, a documentary that used face swaps to protect the privacy of Chechen torture survivors who were persecuted because of their sexual orientation. AI face swaps that replace an entire face with another were perceived as more human-like and less unsettling compared to partial face swaps that left the survivors’ original eyes unaltered. The full-face swap was deemed the least unsettling even in comparison to the original (unaltered) face. When rendered in full, AI face swaps can appear human and avoid aversive responses in the viewer associated with the uncanny valley.

Automated system for creating training programs for mass professional users

2020 ◽  
pp. 21-27
Author(s):  
V.K. Grigoriev ◽  
A.A. Biryukova ◽  
A. Yu. Volk ◽  
A.S. Ilyushechkin
Keyword(s):  
Experimental Verification ◽  
Training Programs ◽  
Automated System ◽  
Software Product ◽  
Learning Programs ◽  
E Learning ◽  
The Creation ◽  
The Impact

The article discusses the automation of the creation and use of e-learning programs. The impact of automating the learning of a large number of users on the effectiveness of the introduction of a new software product is analyzed. The methods and algorithms that increase the efficiency of creating electronic training programs on example of the author’s automated system “Tutor Builder” are described. The results of experimental verification of the automated system are provided.

Data and visual displays in the Journal of Ecology 1996–2016

2020 ◽  
pp. 147387162098012
Author(s):  
Alon Friedman
Keyword(s):  
Best Practices ◽  
Pearson Correlation ◽  
Single Species ◽  
Data Type ◽  
Reliability Test ◽  
Visual Displays ◽  
Domain Type ◽  
Academic Publications ◽  
The Creation ◽  
The Impact

Scholars in scientific disciplines face unique challenges in the creation of visualizations, especially in publications that require insights derived from analyses to be visually displayed. The literature on visualizations describes different techniques and best practices for the creation of graphs. However, these techniques have not been used to evaluate the impact of visualizations in academic publications. In the field of ecology, as in other scientific fields, graphs are an essential part of journal articles. Little is known about the connections between the kind of data presented and domain in which the researchers conducted their study that together produces the visual graphics. This study focused on articles published in the Journal of Ecology between 1996 and 2016 to explore possible connections between data type, domain, and visualization type. Specifically, this study asked three questions: How many of the graphics published between 1996 and 2016 follow a particular set of recommendations for best practices? What can Pearson correlations reveal about the relationships between type of data, domain of study, and visual displays? Can the findings be examined through an inter-reliability test lens? Out of the 20,080 visualizations assessed, 54% included unnecessary graphical elements in the early part of the study (1996–2010). The most common type of data was univariate (35%) and it was often displayed using line graphs. Twenty-one percent of the articles in the period studied could be categorized under the domain type “single species.” Pearson correlation analysis showed that data type and domain type was positively correlated ( r = 0.08; p ≤ 0.05). Cohen’s kappa for the reliability test was 0.86, suggesting good agreement between the two categories. This study provides evidence that data type and domain types are equally important in determining the type of visualizations found in scientific journals.

scholarly journals An evaluation of the Victorian Salt Reduction Partnership’s advocacy strategy for policy change

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Emalie Rosewarne ◽  
Michael Moore ◽  
Wai-Kwan Chislett ◽  
Alexandra Jones ◽  
Kathy Trieu ◽  
...  
Keyword(s):  
Public Health ◽  
Policy Change ◽  
Action Plan ◽  
Evaluation Framework ◽  
Decision Makers ◽  
Health Advocacy ◽  
Salt Reduction ◽  
Public Health Advocacy ◽  
The Creation ◽  
The Impact

Abstract Background Public health advocacy strategies facilitate policy change by bringing key health issues to the forefront of public and political discourse, influencing decision-makers and public opinion, and increasing policy demand. The Victorian Salt Reduction Partnership (VSRP) was established in 2014 in response to inadequate government action to improve population diets in Australia. This study aimed to evaluate the success of the VSRP’s advocacy strategy in achieving policy change. Methods Documentation of VSRP activities and outputs were collected, and semi-structured interviews conducted as part of a comprehensive process evaluation. For this study, the Kotter Plus 10-step public health advocacy evaluation framework was used to guide data extraction, analysis, and synthesis. Results A sense of urgency for salt reduction was generated by producing evidence and outlining the potential impact of a state-based salt reduction programme. This enabled the creation of a coalition with diverse skills and expertise, which facilitated the development of an innovative and collaborative advocacy action plan. A clear change vision was established, but communication of the vision to decision-makers was lacking, which reduced the impact of the programme as decision-makers were not provided with a clear incentive for policy change. As a result, while programme outputs were achieved, these did not translate to achieving broader strategic goals during a limited-term intervention in a political climate unconcerned with salt. Conclusions The Kotter Plus 10-step framework was a useful tool for evaluating the success of the VSRP advocacy strategy. The framework enabled the identification of key strengths, including the creation of the guiding coalition, and areas where efforts could be improved in future similar strategies, such as effective communication within partnerships and to decision-makers, to better influence policy and improve public health impact.

scholarly journals The Impact of Business Incubator Facilities on Investment Promotion in Jordan: A Case of King Hussein Business Park

2018 ◽  
Vol 8 (3) ◽  
pp. 55
Author(s):  
Ibrahim Alshamaileh ◽  
Fouad Sheikh Salem
Keyword(s):  
Positive Impact ◽  
Business Environment ◽  
Occupancy Rate ◽  
Business Climate ◽  
Business Incubator ◽  
Scarce Resources ◽  
Investment Promotion ◽  
Investment Law ◽  
The Creation ◽  
The Impact

This study aims to measure the impact of facilities provided by King Hussein Business Park on investment promotion. King Hussein Business Park has reached 100% occupancy rate, with a crucial plan for expansion to over 1.4 million m2 of land. The problem of the study lies on how King Hussein Business Park will attract additional investments to occupy the spaces targeted for expansion. Results of the study reveal a significant positive impact of the facilities on investment promotion. The robust infrastructure, complementary services, and investment law benefits influence the creation of attractive business environment for investments. These findings show that countries with scarce resources face many challenges in promoting investment either locally or internationally, and they must improve their business climate for investment promotion. Governments also have the means to make conducting the businesses and projects easier for people.

scholarly journals Disruption, destruction and the creation of ‘the inner cities’: the impact of urban renewal on industry, 1945–1980

Urban History ◽  
2016 ◽  
Vol 44 (3) ◽  
pp. 492-515 ◽  
Author(s):  
ALISTAIR KEFFORD
Keyword(s):  
Inner City ◽  
Urban Renewal ◽  
Economic Activity ◽  
Policy Makers ◽  
Industrial Activities ◽  
Inner Cities ◽  
The Creation ◽  
Post War ◽  
The Impact

ABSTRACT:This article examines the impact of post-war urban renewal on industry and economic activity in Manchester and Leeds. It demonstrates that local redevelopment plans contained important economic underpinnings which have been largely overlooked in the literature, and particularly highlights expansive plans for industrial reorganization and relocation. The article also shows that, in practice, urban renewal had a destabilizing and destructive impact on established industrial activities and exacerbated the inner-city problems of unemployment and disinvestment which preoccupied policy-makers by the 1970s. The article argues that post-war planning practices need to be integrated into wider histories of deindustrialization in British cities.

Beyond Interactive Evolution: Expressing Intentions Through Fitness Functions

Leonardo ◽  
2016 ◽  
Vol 49 (3) ◽  
pp. 251-256 ◽  
Author(s):  
Penousal Machado ◽  
Tiago Martins ◽  
Hugo Amaro ◽  
Pedro H. Abreu
Keyword(s):  
Fitness Function ◽  
Interactive Art ◽  
Support Tool ◽  
Generative Art ◽  
Fitness Functions ◽  
Meta Level ◽  
Evolutionary Art ◽  
Creativity Support ◽  
The Creation ◽  
The Impact

Photogrowth is a creativity support tool for the creation of nonphotorealistic renderings of images. The authors discuss its evolution from a generative art application to an interactive evolutionary art tool and finally into a meta-level interactive art system in which users express their artistic intentions through the design of a fitness function. The authors explore the impact of these changes on the sense of authorship, highlighting the range of imagery that can be produced by the system.

BEYOND BUTRINT: THE ‘MURSI SURVEY’, 2008

2016 ◽  
Vol 111 ◽  
pp. 269-297
Author(s):  
Richard Hodges ◽  
Erika Carr ◽  
Alessandro Sebastiani ◽  
Emanuele Vaccaro
Keyword(s):  
Bronze Age ◽  
Late Antiquity ◽  
Short Report ◽  
Mediterranean Landscapes ◽  
Ancient City ◽  
History Of ◽  
Byzantine Period ◽  
The Creation ◽  
The Impact ◽  
The Town

This article provides a short report on a survey of the region to the east of the ancient city of Butrint, in south-west Albania. Centred on the modern villages of Mursi and Xarra, the field survey provides information on over 80 sites (including standing monuments). Previous surveys close to Butrint have brought to light the impact of Roman Imperial colonisation on its hinterland. This new survey confirms that the density of Imperial Roman sites extends well to the east of Butrint. As in the previous surveys, pre-Roman and post-Roman sites are remarkably scarce. As a result, taking the results of the Butrint Foundation's archaeological excavations in Butrint to show the urban history of the place from the Bronze Age to the Ottoman period, the authors challenge the central theme of urban continuity and impact upon Mediterranean landscapes posited by Horden and Purcell, inThe Corrupting Sea(2000). Instead, the hinterland of Butrint, on the evidence of this and previous field surveys, appears to have had intense engagement with the town in the Early Roman period following the creation of the Roman colony. Significant engagement with Butrint continued in Late Antiquity, but subsequently in the Byzantine period, as before the creation of the colony, the relationship between the town and its hinterland was limited and has left a modest impact upon the archaeological record.

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