Initial Condition Sensitivity of Global Quantities in Magnetohydrodynamic Turbulence

In this paper we study the effect of subtle changes in initial conditions on the evolution of global quantities in two-dimensional Magnetohydrodynamic (MHD) turbulence. We find that a change in the initial phases of complex Fourier modes of the Els\"{a}sser variables, while keeping the initial values of total energy, cross helicity and Alfv\'{e}n ratio unchanged, has a significant effect on the evolution of cross helicity. On the contrary, the total energy and Alfv\'{e}n ratio are insensitive to the initial phases. Our simulations are based on direct numerical simulation using the pseudo-spectral method.Comment: 12 pages LateX, 11 ps figures. Accepted for publication by Physics of Plasma

An Improved Bat Algorithm for the Hybrid Flowshop Scheduling to Minimize Total Job Completion Time

In this paper, we present improved bat algorithm (BA) to solve hybrid flowshop scheduling (HFS) problem, which is a typi- cal NP-hard combinatorial optimization problem with strong engineering production back- grounds. To make algorithms applicable in the HFS problem, we use smallest position value (SPV) rule to associate particles continuous property to discrete job order, greedy method to compute this job order to complete HFS schedule and rank selection rule for particles local search. Computation has three major outcomes: total iteration required to solve the problem, total computation time needed and total job completion time (JCT). Simulation results based on a variety of instances demonstrate the effectiveness, efficiency, and robust- ness of the algorithms. Comparison with particle swarm optimization (PSO) algorithm de- picts that BA gives better results and stable outcomes

Countering Code Injection Attacks With Instruction Set Randomization

We describe a new, general approach for safeguarding systems against any type of code-injection attack. We apply Kerckhoff's principle, by creating process-specific randomized instruction sets (e.g., machine instructions) of the system executing potentially vulnerable software. An attacker who does not know the key to the randomization algorithm will inject code that is invalid for that randomized processor, causing a runtime exception. To determine the difficulty of integrating support for the proposed mechanism in the operating system, we modified the Linux kernel, the GNU binutils tools, and the bochs-x86 emulator. Although the performance penalty is significant, our prototype demonstrates the feasibility of the approach, and should be directly usable on a suitable-modified processor (e.g., the Transmeta Crusoe).Our approach is equally applicable against code-injecting attacks in scripting and interpreted languages, e.g., web-based SQL injection. We demonstrate this by modifying the Perl interpreter to permit randomized script execution. The performance penalty in this case is minimal. Where our proposed approach is feasible (i.e., in an emulated environment, in the presence of programmable or specialized hardware, or in interpreted languages), it can serve as a low-overhead protection mechanism, and can easily complement other mechanisms

Depth Customization of DSpace: Best Practices and Techniques of Institutional Repository at IIT Kanpur, India

4th International Conference on Open RepositoriesThis presentation was part of the session : DSpace User Group PresentationsDate: 2009-05-21 08:30 AM – 10:00 AMRealizing the importance and magnitude of Institutional Repository and global visibility and further research scope, Indian Institute of Technology Kanpur, India has intensively planned and designed a full fledged IR project started in mid 2005. Considering the various characteristics and strategies we have designed a well defined and distinct roadmap for establishing our IR in two phases. In the first phase we have planned the mass digitization of entire theses collection of Masters and Doctoral Dissertations produced from 1963 spanning one million pages with their complex content. The content management and uploading to the content server with extracted metadata encoded in XML from our existing server by an in-house developed script is being organised effectively ensuring adequate quality checking of these pages. Initially manual submission for theses was in place. Now a provision has been made available to researchers to submit their theses online even without submitting any hardcopy in the library. The second phase is conceived of digitizing scholarly publications other than theses from our academic community. Its coverage is extremely appreciable in number and strategy we are using for our IR. Excellent feature of our system is the depth customization of DSpace at several places incorporating enhanced features. We discovered that default features offered by even the latest version of DSpace are not sufficient and adequate for academic community to establish their IR system in its full functionality so as to deliver the right information to the right user at the time it is needed. After a detailed study and research we have incorporated significant features like workflow, additional browse and search options, cross-collection search, linking to keywords/subject/homepage/citation, total count of items in respect of supervisor/subject/citation. Additionally, login user authentication from central database, IP based access restrictions, embargo and encryption on the bit stream are also provided. Redesigned feedback form has also been provided to improve its scope and functionalities of our system. These are unique features of our IR system and these enhanced features may be useful to any system in identical academic environment using DSpace to power their Institutional Repositories.Indian Institute of Technology Kanpur, Indi

Effective Test Pattern Generation using LFSR for Memory Testing

Volume 2 Issue 3 (March 2014

In Praise of an Elementary Identity of Euler

We survey the applications of an elementary identity used by Euler in one of his proofs of the Pentagonal Number Theorem. Using a suitably reformulated version of this identity that we call Euler's Telescoping Lemma, we give alternate proofs of all the key summation theorems for terminating Hypergeometric Series and Basic Hypergeometric Series, including the terminating Binomial Theorem, the Chu--Vandermonde sum, the Pfaff--Saalch\" utz sum, and their $q$-analogues. We also give a proof of Jackson's $q$-analog of Dougall's sum, the sum of a terminating, balanced, very-well-poised $_8\phi_7$ sum. Our proofs are conceptually the same as those obtained by the WZ method, but done without using a computer. We survey identities for Generalized Hypergeometric Series given by Macdonald, and prove several identities for $q$-analogs of Fibonacci numbers and polynomials and Pell numbers that have appeared in combinatorial contexts. Some of these identities appear to be new.Comment: Published versio

GAS CHROMATOGRAPHY-MASS SPECTROSCOPY STUDIES ON ETHANOLIC EXTRACT OF DRIED LEAVES OF CATHARANTHUS ROSEUS

Objective: Phytochemical screening of the ethanolic extract of Catharanthus roseus disclosed the presence of alkaloids, terpenoids, phenols, tannins, saponins, quinines, flavonoids, and proteins. In the present research work, we have identified and confirmed the structures of the constituents present by means of a hyphenated technique of gas chromatography-mass spectrometry (GC-MS) from the extract.Method: Shade-dried leaves of C. roseus were powdered and extracted by means of Soxhlet extraction using ethanol as a solvent. Crude extract obtained was utilized for GC-MS.Results: A total of 15 components were identified, some of which were n-hexadecanoic acid, ethyl ester, Vitamin E, 9,12,15-octadecatrienoic acid,2- [(trimethylsilyl)oxy]-1-[{(trimethylsilyl)oxy}methyl]ethyl ester, phytol, 3-epivindolinine, and oleic acid.Conclusion: GC-MS studies helped us to assess the phytochemical constituents based on retention time, molecular formula, molecular weight and the corroboration of MS libraries. In future, C. roseus leaves may be subjected to diverse types of extraction methodologies, and a number of various elucidated phytoconstituents can be studied for their ethnopharmacological significance and applicability citing literature

Collision of spinning black holes in the close limit

In this paper we consider the collision of spinning holes using first order perturbation theory of black holes (Teukolsky formalism). With these results (along with ones, we published in the past) one can predict the properties of the gravitational waves radiated from the late stage inspiral of two spinning, equal mass black holes. Also we note that the energy radiated by the head-on collision of two spinning holes with spins (that are equal and opposite) aligned along the common axis is more than the case in which the spins are perpendicular to the axis of the collision.Comment: 6 pages, 3 figures, submitted to PR

Adaptation of an evidence-based cardiovascular health intervention for rural African Americans in the Southeast

Background: African Americans (AA) living in the southeast United States have the highest prevalence of cardiovascular diseases (CVD) and rural minorities bear a significant burden of co-occurring CVD risk factors. Few evidence-based interventions (EBI) address social and physical environmental barriers in rural minority communities. We used intervention mapping together with community-based participatory research (CBPR) principles to adapt objectives of a multi-component CVD lifestyle EBI to fit the needs of a rural AA community. We sought to describe the process of using CPBR to adapt an EBI using intervention mapping to an AA rural setting and to identify and document the adaptations mapped onto the EBI and how they enhance the intervention to meet community needs. Methods: Focus groups, dyadic interviews, and organizational web-based surveys were used to assess content interest, retention strategies, and incorporation of auxiliary components to the EBI. Using CBPR principles, community and academic stakeholders met weekly to collaboratively integrate formative research findings into the intervention mapping process. We used a framework developed by Wilstey Stirman et al. to document changes. Results: Key changes were made to the content, context, and training and evaluation components of the existing EBI. A matrix including behavioral objectives from the original EBI and new objectives was developed. Categories of objectives included physical activity, nutrition, alcohol, and tobacco divided into three levels, namely, individual, interpersonal, and environmental. Conclusions: Intervention mapping integrated with principles of CBPR is an efficient and flexible process for adapting a comprehensive and culturally appropriate lifestyle EBI for a rural AA community context