scholarly journals Performance of a Code Migration for the Simulation of Supersonic Ejector Flow to SMP, MIC, and GPU Using OpenMP, OpenMP+LEO, and OpenACC Directives

2015 ◽  
Vol 2015 ◽  
pp. 1-20 ◽  
Author(s):  
C. Couder-Castañeda ◽  
H. Barrios-Piña ◽  
I. Gitler ◽  
M. Arroyo
Keyword(s):  
Boundary Conditions ◽  
Source Code ◽  
Acceleration Factor ◽  
Xeon Phi ◽  
Low Level ◽  
Supersonic Ejector ◽  
Development Costs ◽  
Code Migration ◽  
The Creation ◽  
True Alternative

A serial source code for simulating a supersonic ejector flow is accelerated using parallelization based on OpenMP and OpenACC directives. The purpose is to reduce the development costs and to simplify the maintenance of the application due to the complexity of the FORTRAN source code. This research follows well-proven strategies in order to obtain the best performance in both OpenMP and OpenACC. OpenMP has become the programming standard for scientific multicore software and OpenACC is one true alternative for graphics accelerators without the need of programming low level kernels. The strategies using OpenMP are oriented towards reducing the creation of parallel regions, tasks creation to handle boundary conditions, and a nested control of the loop time for the programming in offload mode specifically for the Xeon Phi. In OpenACC, the strategy focuses on maintaining the data regions among the executions of the kernels. Experiments for performance and validation are conducted here on a 12-core Xeon CPU, Xeon Phi 5110p, and Tesla C2070, obtaining the best performance from the latter. The Tesla C2070 presented an acceleration factor of 9.86X, 1.6X, and 4.5X compared against the serial version on CPU, 12-core Xeon CPU, and Xeon Phi, respectively.

scholarly journals Implementação de Novas Funcionalidades no Sistema de Visualização de Dados da Plataforma ExpeRT

2021 ◽  
Author(s):  
Eduardo Marmitt ◽  
Helmo Alan Batista de Araújo ◽  
Mariângela Mendes Recco ◽  
Matheus Lorenzato Braga
Keyword(s):  
Source Code ◽  
Web Page ◽  
Java Language ◽  
The Creation

The ExpeRT Platform is a system created to assist in the development of pedagogical experimental. After tests accomplished in classrooms, deficits were pointed out in the Data Viewer System (DVS), by the teacher and creator of the ExpeRT Platform. This work consists of enhancing the ExpeRT Platform by using the Java language to modify the data viewer system (DVS) source code and solve the issues pointed out, leading to an update for the seventh version. In addition, provide the creation of a web page as your portal to supply the system’s download.

scholarly journals LGM Summer Climate on the Southern Margin of the Laurentide Ice Sheet: Wet or Dry?*

2005 ◽  
Vol 18 (16) ◽  
pp. 3317-3338 ◽  
Author(s):  
David H. Bromwich ◽  
E. Richard Toracinta ◽  
Robert J. Oglesby ◽  
James L. Fastook ◽  
Terence J. Hughes
Keyword(s):  
Boundary Conditions ◽  
Great Plains ◽  
Land Surface ◽  
Thermal Gradient ◽  
Mesoscale Model ◽  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Low Level ◽  
Summer Climate ◽  
Southern Margin

Abstract Regional climate simulations are conducted using the Polar fifth-generation Pennsylvania State University (PSU)–NCAR Mesoscale Model (MM5) with a 60-km horizontal resolution domain over North America to explore the summer climate of the Last Glacial Maximum (LGM: 21 000 calendar years ago), when much of the continent was covered by the Laurentide Ice Sheet (LIS). Output from a tailored NCAR Community Climate Model version 3 (CCM3) simulation of the LGM climate is used to provide the initial and lateral boundary conditions for Polar MM5. LGM boundary conditions include continental ice sheets, appropriate orbital forcing, reduced CO2 concentration, paleovegetation, modified sea surface temperatures, and lowered sea level. The simulated LGM summer climate is characterized by a pronounced low-level thermal gradient along the southern margin of the LIS resulting from the juxtaposition of the cold ice sheet and adjacent warm ice-free land surface. This sharp thermal gradient anchors the midtropospheric jet stream and facilitates the development of synoptic cyclones that track over the ice sheet, some of which produce copious liquid precipitation along and south of the LIS terminus. Precipitation on the southern margin is orographically enhanced as moist southerly low-level flow (resembling a contemporary Great Plains low-level jet configuration) in advance of the cyclone is drawn up the ice sheet slope. Composites of wet and dry periods on the LIS southern margin illustrate two distinctly different atmospheric flow regimes. Given the episodic nature of the summer rain events, it may be possible to reconcile the model depiction of wet conditions on the LIS southern margin during the LGM summer with the widely accepted interpretation of aridity across the Great Plains based on geological proxy evidence.

Entering history? Archaeologists as intellectuals à la recherche du temps perdu

2013 ◽  
Vol 20 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Nathan Schlanger
Keyword(s):  
Decision Making ◽  
National Identity ◽  
Local Communities ◽  
Public Intellectuals ◽  
Low Level ◽  
Public Debates ◽  
The Media ◽  
The Creation

AbstractFollowing some comments on the notion of ‘public’ intellectuals (can they be otherwise?), this brief paper focuses on the intellectual roles that could be played by archaeologists today. Exposure to the media, usually following some spectacular discovery, serves to confirm the romantico-empirical image of the discipline, but should also lead to an engagement with key public debates. Three such debates are indicated: the idea that ‘African man has yet to enter history’ as expressed by the former French president; the creation of a Maison de l'histoire de France under the tutelage of the Ministry of National Identity; and, across the Channel, the Localism Bill, which pushes decision making to an untenably low level while promoting a historically and archaeologically questionable view of local communities.

Simulations of the 2004 North American Monsoon: NAMAP2

2009 ◽  
Vol 22 (24) ◽  
pp. 6716-6740 ◽  
Author(s):  
D. S. Gutzler ◽  
L. N. Long ◽  
J. Schemm ◽  
S. Baidya Roy ◽  
M. Bosilovich ◽  
...  
Keyword(s):  
Boundary Conditions ◽  
North American ◽  
Warm Season ◽  
North American Monsoon ◽  
Regional Models ◽  
Global Models ◽  
Low Level ◽  
The Core ◽  
The North ◽  
Low Level Jet

Abstract The second phase of the North American Monsoon Experiment (NAME) Model Assessment Project (NAMAP2) was carried out to provide a coordinated set of simulations from global and regional models of the 2004 warm season across the North American monsoon domain. This project follows an earlier assessment, called NAMAP, that preceded the 2004 field season of the North American Monsoon Experiment. Six global and four regional models are all forced with prescribed, time-varying ocean surface temperatures. Metrics for model simulation of warm season precipitation processes developed in NAMAP are examined that pertain to the seasonal progression and diurnal cycle of precipitation, monsoon onset, surface turbulent fluxes, and simulation of the low-level jet circulation over the Gulf of California. Assessment of the metrics is shown to be limited by continuing uncertainties in spatially averaged observations, demonstrating that modeling and observational analysis capabilities need to be developed concurrently. Simulations of the core subregion (CORE) of monsoonal precipitation in global models have improved since NAMAP, despite the lack of a proper low-level jet circulation in these simulations. Some regional models run at higher resolution still exhibit the tendency observed in NAMAP to overestimate precipitation in the CORE subregion; this is shown to involve both convective and resolved components of the total precipitation. The variability of precipitation in the Arizona/New Mexico (AZNM) subregion is simulated much better by the regional models compared with the global models, illustrating the importance of transient circulation anomalies (prescribed as lateral boundary conditions) for simulating precipitation in the northern part of the monsoon domain. This suggests that seasonal predictability derivable from lower boundary conditions may be limited in the AZNM subregion.

scholarly journals TOURISM AS A DRIVER OF INNOVATIVE DEVELOPMENT OF RURAL AREAS (ON THE EXAMPLE OF THE RURAL SETTLEMENT ZARECHNOYE IN VELIKOUSTYUG DISTRICT OF THE VOLOGDA REGION)

2021 ◽  
pp. 44-51
Author(s):  
V.S. Orlova ◽  
Keyword(s):  
Rural Development ◽  
Rural Areas ◽  
Local Population ◽  
Rural Settlement ◽  
Development Economic ◽  
Innovative Development ◽  
Conceptual Approach ◽  
Low Level ◽  
Vologda Region ◽  
The Creation

Currently, a significant part of the rural territories of the regions of Russia is characterized by low production potential, a low level of agricultural development. For such territories, tourism could be the driver of socio-economic growth and innovative development in time. It was therefore increasingly important to develop a conceptual approach to rural development based on tourism innovations, which was the aim of the study. To achieve the goal, the following methods were used: conceptual approach to rural development, economic and statistical methods, sociological survey, expert assessment, data capture and other methods of analysis and synthesis. The results of the survey: an analysis of the socio-economic situation of the rural territory was carried out on the example of the rural settlement of Zarechnoye in the Veliko-Ustyug district of the Vologda region, the main problems were identified: demographic and infrastructural, as well as a low level of productive potential. Based on the analysis, a conceptual approach to rural development was proposed through the development of tourism innovations. The conceptual goal is to increase the attractiveness and innovative development of the rural settlement of Zarechnoye based on its natural and cultural and historical potential. The projects proposed within the framework of the approach were aimed at improving and increasing the attractiveness of the territory for internal (local population) and external entities — investors, tourists, to promote the settlement in the external environment as a promising area for life and a favorable place for recreation. The target indicators for the development of rural settlement had been set: an annual increase in the number of residents registered on the territory of the settlement, and the formation of a stable inbound tourist flow. Scientific novelty: the originality of the author’s conceptual approach to the development of rural areas was determined by the possibility of their integrated development through the creation of a coastal tourist and recreational zone, which made it possible to fully realize the cultural, historical and natural potential of rural settlements. Practical significance: the main provisions and conclusions of the article can be used by regional and local authorities and management to develop programs and projects for the development of tourist activities in rural areas. Conclusion: The study suggests that the creation of tourist and recreational areas in rural areas, taking into account the cultural and natural heritage of settlements, will contrib¬ute to the effective realization of their tourism potential and can become an incentive for innovative development of rural areas in modern conditions.

scholarly journals Talk Is Silver, Code Is Gold? Beyond Traditional Notions of Contribution in Peer Production: The Case of Drupal

2021 ◽  
Vol 3 ◽  
Author(s):  
David Rozas ◽  
Nigel Gilbert ◽  
Paul Hodkinson ◽  
Samer Hassan
Keyword(s):  
Qualitative Study ◽  
Empirical Evidence ◽  
Source Code ◽  
Free Software ◽  
The Internet ◽  
Software Project ◽  
Peer Production ◽  
Digital Platforms ◽  
Digital Commons ◽  
The Creation

Peer production communities are based on the collaboration of communities of people, mediated by the Internet, typically to create digital commons, as in Wikipedia or free software. The contribution activities around the creation of such commons (e.g., source code, articles, or documentation) have been widely explored. However, other types of contribution whose focus is directed toward the community have remained significantly less visible (e.g., the organization of events or mentoring). This work challenges the notion of contribution in peer production through an in-depth qualitative study of a prominent “code-centric” example: the case of the free software project Drupal. Involving the collaboration of more than a million participants, the Drupal project supports nearly 2% of websites worldwide. This research (1) offers empirical evidence of the perception of “community-oriented” activities as contributions, and (2) analyzes their lack of visibility in the digital platforms of collaboration. Therefore, through the exploration of a complex and “code-centric” case, this study aims to broaden our understanding of the notion of contribution in peer production communities, incorporating new kinds of contributions customarily left invisible.

scholarly journals Crowdsourced Security Reconstitution for Wireless Sensor Networks: Secrecy Amplification

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 5041 ◽  
Author(s):  
Radim Ostadal ◽  
Vashek Matyas ◽  
Petr Svenda ◽  
Lukas Nemec
Keyword(s):  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Source Code ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Network Node ◽  
Test Results ◽  
Low Level ◽  
The Past ◽  
Simulated Network

Research in the area of security for Wireless Sensor Networks over the past two decades has yielded many interesting findings. We focus on the topic of (re-)securing link keys between sensor nodes through so-called secrecy amplification (SA) protocols. Crowdsourcing is at the very heart of these SA protocols. Not only do SA protocols work wonders even for low-level constrained nodes with no tamper resistance, they exhibit astonishing performance in networks under significant attacker control. Our work shows that even when 50% of all network links are compromised, SA protocols can re-secure over 90% of the link keys through an intriguingly simple crowdsourcing mechanism. These protocols allow us to re-take control without any broadly coordinated cooperation, without knowledge of the compromised links, with only very limited knowledge of each particular network node and independently of decisions made by other nodes. Our article first outlines the principles of and presents existing approaches to SA, introducing most of the important related concepts, then presents novel conclusive results for a realistic attacker model parametrised by attacker behaviour and capabilities. We undertook this work using two very different simulators, and we present here the results of analyses and detailed comparisons that have not previously been available. Finally, we report the first real, non-simulated network test results for the most attractive SA protocol, our implementations of which are available as open-source code for two platforms: Arduino and TinyOS. This work demonstrates the practical usability (and the attractive performance) of SA, serving as a ripe technology enabler for (among others) networks with many potentially compromised low-level devices.

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