36,937 research outputs found
Pocket-hydro turbine into capsule hydro turbine
The capsule hydro turbine (CaHT) is a continuous power machine in which a wheel or rotor typically filted whereas produce electricity. It is designed like a capsule shape which has two twin turbines on both output to generate energy as an alternative power supply. The devide is capable of producing output of 12v to power up electrical applicances. The device consist of dynamos, turbines, charging circuit, battery, inverter, and wire cables. The result of the capsule hydro turbine (CaHT) field is presented in three types of graphs as in this paper. The optimum voltage of battery was 6.97v. By using these terms, the research project has successfully improvised the pocket hydro turbine (PHT) into capsule hydro turbine (CaHT
A practical guide to computer simulations
Here practical aspects of conducting research via computer simulations are
discussed. The following issues are addressed: software engineering,
object-oriented software development, programming style, macros, make files,
scripts, libraries, random numbers, testing, debugging, data plotting, curve
fitting, finite-size scaling, information retrieval, and preparing
presentations.
Because of the limited space, usually only short introductions to the
specific areas are given and references to more extensive literature are cited.
All examples of code are in C/C++.Comment: 69 pages, with permission of Wiley-VCH, see http://www.wiley-vch.de
(some screenshots with poor quality due to arXiv size restrictions) A
comprehensively extended version will appear in spring 2009 as book at
Word-Scientific, see http://www.worldscibooks.com/physics/6988.htm
Exploring Current Practice of Using Technology to Support Collaborative Argumentation in Science Classrooms
The purpose of this qualitative study was to explore how middle school science teachers enact the practice of using technology to support collaborative argumentation in their science classroom. This study employed qualitative case study and drew on data sources of interviews and observations. This study identified two themes. Six teachers regarded scientific argumentation as an important science practice, but five of them integrated this practice into their science class without formally introducing it. All teachers integrated different forms of technology to engage students in scientific argumentation. In this study, the findings suggested there is a need to provide professional development for teachers to learn about scientific argumentation. The findings can be used as a basis for the design and development of professional development training experiences for in-servic
AMP: A Science-driven Web-based Application for the TeraGrid
The Asteroseismic Modeling Portal (AMP) provides a web-based interface for
astronomers to run and view simulations that derive the properties of Sun-like
stars from observations of their pulsation frequencies. In this paper, we
describe the architecture and implementation of AMP, highlighting the
lightweight design principles and tools used to produce a functional
fully-custom web-based science application in less than a year. Targeted as a
TeraGrid science gateway, AMP's architecture and implementation are intended to
simplify its orchestration of TeraGrid computational resources. AMP's web-based
interface was developed as a traditional standalone database-backed web
application using the Python-based Django web development framework, allowing
us to leverage the Django framework's capabilities while cleanly separating the
user interface development from the grid interface development. We have found
this combination of tools flexible and effective for rapid gateway development
and deployment.Comment: 7 pages, 2 figures, in Proceedings of the 5th Grid Computing
Environments Worksho
The SOS Platform: Designing, Tuning and Statistically Benchmarking Optimisation Algorithms
open access articleWe present Stochastic Optimisation Software (SOS), a Java platform facilitating the algorithmic design process and the evaluation of metaheuristic optimisation algorithms. SOS reduces the burden of coding miscellaneous methods for dealing with several bothersome and time-demanding tasks such as parameter tuning, implementation of comparison algorithms and testbed problems, collecting and processing data to display results, measuring algorithmic overhead, etc. SOS provides numerous off-the-shelf methods including: (1) customised implementations of statistical tests, such as the Wilcoxon rank-sum test and the Holm–Bonferroni procedure, for comparing the performances of optimisation algorithms and automatically generating result tables in PDF and formats; (2) the implementation of an original advanced statistical routine for accurately comparing couples of stochastic optimisation algorithms; (3) the implementation of a novel testbed suite for continuous optimisation, derived from the IEEE CEC 2014 benchmark, allowing for controlled activation of the rotation on each testbed function. Moreover, we briefly comment on the current state of the literature in stochastic optimisation and highlight similarities shared by modern metaheuristics inspired by nature. We argue that the vast majority of these algorithms are simply a reformulation of the same methods and that metaheuristics for optimisation should be simply treated as stochastic processes with less emphasis on the inspiring metaphor behind them
Cover-Encodings of Fitness Landscapes
The traditional way of tackling discrete optimization problems is by using
local search on suitably defined cost or fitness landscapes. Such approaches
are however limited by the slowing down that occurs when the local minima that
are a feature of the typically rugged landscapes encountered arrest the
progress of the search process. Another way of tackling optimization problems
is by the use of heuristic approximations to estimate a global cost minimum.
Here we present a combination of these two approaches by using cover-encoding
maps which map processes from a larger search space to subsets of the original
search space. The key idea is to construct cover-encoding maps with the help of
suitable heuristics that single out near-optimal solutions and result in
landscapes on the larger search space that no longer exhibit trapping local
minima. We present cover-encoding maps for the problems of the traveling
salesman, number partitioning, maximum matching and maximum clique; the
practical feasibility of our method is demonstrated by simulations of adaptive
walks on the corresponding encoded landscapes which find the global minima for
these problems.Comment: 15 pages, 4 figure
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