857 research outputs found

    A Hybrid Laser Ultrasonic Based Systemf ro Composite Molding

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    Conventional piezoelectric based ultrasonic systems have been extensively employed for material characterization. These systems however, have been challenged by the recent need to rapidly scan large areas of new materials such as composites having complex geometry. A promising candidate addressing this issue is laser ultrasonics. Though laser ultrasonics is not new and has generated considerable research interest in the past two decades, its industrial acceptance has been limited. Among its many benefits, laser ultrasonics promise the flexibility of a couplant free inspection system. Pulsed lasers, in particular, offer energy concentration at high repetition rates which can be readily directed at any location on the specimen for interrogation purposes. The detection of laser ultrasound is usually done through Michaelson or Fabry-Perot type interferometric systems. Though these detection systems have the advantage of couplant free detection, they constitute a major component of system cost owing to the precision required. The sensitivity of such systems are also not satisfactory

    An investigation of a deep learning based malware detection system

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    We investigate a Deep Learning based system for malware detection. In the investigation, we experiment with different combination of Deep Learning architectures including Auto-Encoders, and Deep Neural Networks with varying layers over Malicia malware dataset on which earlier studies have obtained an accuracy of (98%) with an acceptable False Positive Rates (1.07%). But these results were done using extensive man-made custom domain features and investing corresponding feature engineering and design efforts. In our proposed approach, besides improving the previous best results (99.21% accuracy and a False Positive Rate of 0.19%) indicates that Deep Learning based systems could deliver an effective defense against malware. Since it is good in automatically extracting higher conceptual features from the data, Deep Learning based systems could provide an effective, general and scalable mechanism for detection of existing and unknown malware.Comment: 13 Pages, 4 figure

    Semi-Mechanized Harvesting Solutions for Cultivated Fodder Crops

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    In case of harvesting and threshing, the level of mechanization in India is 60-70 per cent for wheat and rice and less than five per cent for other crops (Mehta et al., 2014) that include fodder also. Herrmann et al.(2011) established that overall area capacities of machine decreased the by 4-24 per cent on taking finer chopping length of 4-6 mm compared to common chopping length of 8-10 mm in the ensiling chain of maize - establishing that finer work in ensiling commands less capacities and higher input costs. Since there is a strong correlation between effective field capacity and both crop yield and field area (Amiama et al., 2008), it is advisable to go for appropriate machine for fodder harvesting depending on the requirement of crop and field. Semi-automatic machines provide comparatively low cost workable solution in such conditions. In semi-mechanized harvesting of fodder, cutting of crop is done by machine and subsequent operations of collection, gathering, feeding to chaffing machines and feeding to animals are done manually. Such machines are discussed here

    On The Phase Structure and Thermodynamic Geometry of R-Charged Black Holes

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    We study the phase structure and equilibrium state space geometry of R-charged black holes in D=5D = 5, 4 and 7 and the corresponding rotating D3D3, M2M2 and M5M5 branes. For various charge configurations of the compact black holes in the canonical ensemble we demonstrate new liquid-gas like phase coexistence behaviour culminating in second order critical points. The critical exponents turn out to be the same as that of four dimensional asymptotically AdS black holes in Einstein Maxwell theory. We further establish that the regions of stability for R-charged black holes are, in some cases, more constrained than is currently believed, due to properties of some of the response coefficients. The equilibrium state space scalar curvature is calculated for various charge configurations, both for the case of compact as well as flat horizons and its asymptotic behaviour with temperature is established.Comment: 1 + 33 pages, LaTeX, 25 figures. References adde

    Phase transition and scaling behavior of topological charged black holes in Horava-Lifshitz gravity

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    Gravity can be thought as an emergent phenomenon and it has a nice "thermodynamic" structure. In this context, it is then possible to study the thermodynamics without knowing the details of the underlying microscopic degrees of freedom. Here, based on the ordinary thermodynamics, we investigate the phase transition of the static, spherically symmetric charged black hole solution with arbitrary scalar curvature 2k2k in Ho\v{r}ava-Lifshitz gravity at the Lifshitz point z=3z=3. The analysis is done using the canonical ensemble frame work; i.e. the charge is kept fixed. We find (a) for both k=0k=0 and k=1k=1, there is no phase transition, (b) while k=−1k=-1 case exhibits the second order phase transition within the {\it physical region} of the black hole. The critical point of second order phase transition is obtained by the divergence of the heat capacity at constant charge. Near the critical point, we find the various critical exponents. It is also observed that they satisfy the usual thermodynamic scaling laws.Comment: Minor corrections, refs. added, to appear in Class. Quant. Grav. arXiv admin note: text overlap with arXiv:1111.0973 by other author

    Matching of the continuous gravitational wave in an all sky search

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    We investigate the matching of continuous gravitational wave (CGW) signals in an all sky search with reference to Earth based laser interferometric detectors. We consider the source location as the parameters of the signal manifold and templates corresponding to different source locations. It has been found that the matching of signals from locations in the sky that differ in their co-latitude and longitude by π\pi radians decreases with source frequency. We have also made an analysis with the other parameters affecting the symmetries. We observe that it may not be relevant to take care of the symmetries in the sky locations for the search of CGW from the output of LIGO-I, GEO600 and TAMA detectors.Comment: 16 pages, 7 figures, 3 Tables, To appear in Int. J. Mod. Phys.

    Digital Library of IIITM-K – Experiences of Next Generation resource centre

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    Digital Library has many features that make it distinct from traditional libraries. These features make it an excellent medium to address information and interaction services related to quality of education, and management of learning environments. While the paper libraries have become very expensive and are the prerogative of only a few well endowed institutions, Digital Libraries make these services and more at affordable costs. This will remove the digital divide between developed and developing nations in long run. Transversal E-Networks [TEN] a company under incubation at IIITM-K has developed an academic aggregation server concept in which several academic functions such as Course Management, Authoring, and collaborative group-work are built around their unique metadata standards compliant Digital Library implementation. This server called “ACADO” is being field-tested as central information server for Indian Institute of Information Technology – Kerala. The server has more than proven its effectiveness in increasing the productivity and quality of academic collaboration, management of learning environment and research in the institution. The same server can network itself with similar servers in other institutions and form as Information, Knowledge or Educational Grids across the different Digital Library spaces
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