scholarly journals Development and Execution of an Impact Cratering Application on a Computational Grid

2005 ◽  
Vol 13 (1) ◽  
pp. 19-30
Author(s):  
E. Huedo ◽  
A. Lepinette ◽  
R.S. Montero ◽  
I.M. Llorente ◽  
L. Vázquez

Impact cratering is an important geological process of special interest in Astrobiology. Its numerical simulation comprises the execution of a high number of tasks, since the search space of input parameter values includes the projectile diameter, the water depth and the impactor velocity. Furthermore, the execution time of each task is not uniform because of the different numerical properties of each experimental configuration. Grid technology is a promising platform to execute this kind of applications, since it provides the end user with a performance much higher than that achievable on any single organization. However, the scheduling of each task on a Grid involves challenging issues due to the unpredictable and heterogeneous behavior of both the Grid and the numerical code. This paper evaluates the performance of a Grid infrastructure based on the Globus toolkit and the GridWay framework, which provides the adaptive and fault tolerance functionality required to harness Grid resources, in the simulation of the impact cratering process. The experiments have been performed on a testbed composed of resources shared by five sites interconnected by RedIRIS, the Spanish Research and Education Network.

2015 ◽  
Vol 5 (4) ◽  
pp. 208-214
Author(s):  
Платонова ◽  
Marina Platonova ◽  
Платонов ◽  
Aleksey Platonov ◽  
Драпалюк ◽  
...  

Currently, the traffic safety on the railways remains a topical problem of removing unwanted trees and shrubs in the right of way of railways. To improve the efficiency removal of unwanted shoots and branches and stumps, reducing the share of manual labor and facilitation of staff by the authors in 2015 were investigated little links resources saving compact means of mechanization, allowing their use in hard to reach places. These means of mechanization considered in combination with modern the vehicles, which can provide them with the necessary energy, both on the railroad track, and away from it. The design scheme drawn up manipulators for mathematical description of the motion of their units in the plan and profile of the railway, shows a diagram of the dynamic interaction between the rotary operating element with tree and shrub vegetation and stumps, and on the basis of these formulas and reasoned input parameter values it was built a number of plots. The article presents the main findings and recommendations of the study of kinematics and dynamics little links of the mechanism of forest machines. It was concluded that a number of promising kinematic schemes associated with the rotation of the body part telescopic of manipulators machines, substantiated possible working range of the of manipulators according to the scheme of their location on the machine base, a certain range of angles of rotation around the axis of the working equipment of its fastening, the issues of the impact of deviations small diameter unwanted shoots from the vertical cutting force.


2020 ◽  
Vol 16 (10) ◽  
pp. 1960-1979
Author(s):  
N.A. Egina ◽  
E.S. Zemskova

Subject. The study focuses on the impact of the digital economy determinants of the education transformation. Objectives. The article provides our own approach treating the education capital as a specific asset of the digital economy, which has an acceleration effect and sets up new trends in education through integrative networks. Methods. The study is based on principles of the systems integration, cross-disciplinary and multidisciplinary approaches. Results. The socio-economic progress was found to be determined with properties of human capital, which are solely specific to the digital economy. In new circumstances, it gets more important for actors of global, national, corporate and social networks to more actively cooperate within distributed networks in order to train high professionals, who would have skills in information networks. Thus, they would raise a new form of human capital – the capital of network education (network-based education capital). We describe positive externalities that arise when the educational sector joins communication processes. We illustrate how educational forms evolves, which are typical of a certain phase of the socio-economic development. The education capital was discovered to grow into a specific asset generating the quasi-rent and working as a social ladder only provided more actors are involved into the network. Conclusions and Relevance. Studying the evolution of educational forms through the cross-disciplinary method, we discovered the need for a system approach, which would help substantiate its transformation in the time of the digital economy, and the emergence of network-based education. These are technologies and tools of the digital economy that become unique factors generating the acceleration effect of the educational capital and ensuring the use of diverse network effects for the formation of intellectual capital and their social transformation.


2006 ◽  
Vol 41 (1) ◽  
pp. 72-83 ◽  
Author(s):  
Zhe Zhang ◽  
Eric R. Hall

Abstract Parameter estimation and wastewater characterization are crucial for modelling of the membrane enhanced biological phosphorus removal (MEBPR) process. Prior to determining the values of a subset of kinetic and stoichiometric parameters used in ASM No. 2 (ASM2), the carbon, nitrogen and phosphorus fractions of influent wastewater at the University of British Columbia (UBC) pilot plant were characterized. It was found that the UBC wastewater contained fractions of volatile acids (SA), readily fermentable biodegradable COD (SF) and slowly biodegradable COD (XS) that fell within the ASM2 default value ranges. The contents of soluble inert COD (SI) and particulate inert COD (XI) were somewhat higher than ASM2 default values. Mixed liquor samples from pilot-scale MEBPR and conventional enhanced biological phosphorus removal (CEBPR) processes operated under parallel conditions, were then analyzed experimentally to assess the impact of operation in a membrane-assisted mode on the growth yield (YH), decay coefficient (bH) and maximum specific growth rate of heterotrophic biomass (µH). The resulting values for YH, bH and µH were slightly lower for the MEBPR train than for the CEBPR train, but the differences were not statistically significant. It is suggested that MEBPR simulation using ASM2 could be accomplished satisfactorily using parameter values determined for a conventional biological phosphorus removal process, if MEBPR parameter values are not available.


Author(s):  
J. R. Barnes ◽  
C. A. Haswell

AbstractAriel’s ambitious goal to survey a quarter of known exoplanets will transform our knowledge of planetary atmospheres. Masses measured directly with the radial velocity technique are essential for well determined planetary bulk properties. Radial velocity masses will provide important checks of masses derived from atmospheric fits or alternatively can be treated as a fixed input parameter to reduce possible degeneracies in atmospheric retrievals. We quantify the impact of stellar activity on planet mass recovery for the Ariel mission sample using Sun-like spot models scaled for active stars combined with other noise sources. Planets with necessarily well-determined ephemerides will be selected for characterisation with Ariel. With this prior requirement, we simulate the derived planet mass precision as a function of the number of observations for a prospective sample of Ariel targets. We find that quadrature sampling can significantly reduce the time commitment required for follow-up RVs, and is most effective when the planetary RV signature is larger than the RV noise. For a typical radial velocity instrument operating on a 4 m class telescope and achieving 1 m s−1 precision, between ~17% and ~ 37% of the time commitment is spent on the 7% of planets with mass Mp < 10 M⊕. In many low activity cases, the time required is limited by asteroseismic and photon noise. For low mass or faint systems, we can recover masses with the same precision up to ~3 times more quickly with an instrumental precision of ~10 cm s−1.


2008 ◽  
Vol 17 (5) ◽  
pp. 638 ◽  
Author(s):  
Edwin Jimenez ◽  
M. Yousuff Hussaini ◽  
Scott Goodrick

The purpose of the present work is to quantify parametric uncertainty in the Rothermel wildland fire spread model (implemented in software such as BehavePlus3 and FARSITE), which is undoubtedly among the most widely used fire spread models in the United States. This model consists of a non-linear system of equations that relates environmental variables (input parameter groups) such as fuel type, fuel moisture, terrain, and wind to describe the fire environment. This model predicts important fire quantities (output parameters) such as the head rate of spread, spread direction, effective wind speed, and fireline intensity. The proposed method, which we call sensitivity derivative enhanced sampling, exploits sensitivity derivative information to accelerate the convergence of the classical Monte Carlo method. Coupled with traditional variance reduction procedures, it offers up to two orders of magnitude acceleration in convergence, which implies that two orders of magnitude fewer samples are required for a given level of accuracy. Thus, it provides an efficient method to quantify the impact of input uncertainties on the output parameters.


Author(s):  
Singh A ◽  
Jenkins C ◽  
Calys Tagoe B ◽  
Arulogun OS ◽  
Sarfo S ◽  
...  

2011 ◽  
Vol 16 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Kimberly Mann Bruch ◽  
Hans-Werner Braun ◽  
Susan Teel

For several years, National Park Service scientists, historians, and educators have been working with National Science Foundation-funded High Performance Wireless Research and Education Network (HPWREN) researchers on developing, implementing, and evaluating Live Interactive Virtual Explorations (LIVE) at several sites. The LIVE activities utilize computers with headsets and microphones to link National Park Service sites with an array of audiences. The two case studies in this paper examine the effectiveness of LIVE activities that allow Washington, DC, inner-city youth to explore two hard-to-reach National Park Service sites: Knife River Indian Villages National Historic Site in North Dakota and the Hawaii Volcanoes National Park.


Sign in / Sign up

Export Citation Format

Share Document