Genuine Forgery Signature Detection using Radon Transform and K-Nearest Neighbour

Authentication is very much essential in managing security. In modern times, it is one in all priorities. With the advent of technology, dialogue with machines becomes automatic. As a result, the need for authentication for a variety of security purposes is rapidly increasing. For this reason, biometrics-based certification is gaining dramatic momentum. The proposed method describes an off-line Genuine/ Forgery signature classification system using radon transform and K-Nearest Neighbour classifier. Every signature features are extracted by radon transform and they are aligned to get the statistic information of his signature. To align the two signatures, the algorithm used is Extreme Points Warping. Many forged and genuine signatures are selected in K-Nearest Neighbour classifier training. By aligning the test signature with each and every reference signatures of the user, verification of test signature is done. Then the signature can be found whether it is genuine or forgery. A K-Nearest Neighbour is used for classification for the different datasets. The result determines how the proposed procedure is exceeds the current state-of-the-art technology. Approximately, the proposed system’s performance is 90 % in signature verification system

Optical scattering for security applications

Laser Surface Authentication (LSA) has emerged in recent years as a potentially disruptive tracking and authentication technology. A strong need for such a solution in a variety of industries drove the implementation of the technology faster than the scientific understanding could keep up. The drive to miniaturise and simplify, the need to be robust against real-world problems like damage and misuse, and not least, intellectual curiosity, make it clear that a firmer scientific footing is important as the technology matures. Existing scattering and biometric work are reviewed, and LSA is introduced as a technology. The results of field-work highlight the restrictions which are encountered when the technology is applied. Analysis of the datasets collected in the trial provide, first, an indication of the performance of LSA under real-world conditions and, second, insight into the potential shortcomings of the technique. Using the particulars of the current sensor’s geometry, the LSA signal is characterised. Measurements are made of the decorrelation of the signature with linear and rotational offsets, and it is concluded that while surface microstructure has a strong impact on the rate of decorrelation, this dependency is not driven by the surface’s feature size. A new series of experiments examine that same decorrelation for interference effects with different illumination conditions, and conclude that laser speckle is not an adequate explanation for the phenomenon. The results of this experimental work inform a mathematical description of LSA based on a combination of existing bi-static scattering models used in physics and ray-tracing, which is implemented numerically. The results of the model are found to be a good fit to experimental work, and new predictions are made about LSA

A Telescope Search for Decaying Relic Axions

A search for optical line emission from the two-photon decay of relic axions was conducted in the galaxy clusters Abell 2667 and 2390, using spectra from the VIMOS (Visible Multi-Object Spectrograph) integral field unit at the Very Large Telescope. New upper limits to the two-photon coupling of the axion are derived, and are at least a factor of 3 more stringent than previous upper limits in this mass window. The improvement follows from larger collecting area, integration time, and spatial resolution, as well as from improvements in signal to noise and sky subtraction made possible by strong-lensing mass models of these clusters. The new limits either require that the two-photon coupling of the axion be extremely weak or that the axion mass window between 4.5 eV and 7.7 eV be closed. Implications for sterile-neutrino dark matter are discussed briefly also.Comment: 14 pages, 10 figures, replaced with version published in Phys. Rev.

Stellar Intensity Interferometry: Prospects for sub-milliarcsecond optical imaging

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their circumstellar disks and winds, or mapping out patterns of nonradial pulsations across stellar surfaces. Intensity interferometry (pioneered by Hanbury Brown and Twiss) connects telescopes only electronically, and is practically insensitive to atmospheric turbulence and optical imperfections, permitting observations over long baselines and through large airmasses, also at short optical wavelengths. The required large telescopes with very fast detectors are becoming available as arrays of air Cherenkov telescopes, distributed over a few square km. Digital signal handling enables very many baselines to be synthesized, while stars are tracked with electronic time delays, thus synthesizing an optical interferometer in software. Simulated observations indicate limiting magnitudes around m(v)=8, reaching resolutions ~30 microarcsec in the violet. The signal-to-noise ratio favors high-temperature sources and emission-line structures, and is independent of the optical passband, be it a single spectral line or the broad spectral continuum. Intensity interferometry provides the modulus (but not phase) of any spatial frequency component of the source image; for this reason image reconstruction requires phase retrieval techniques, feasible if sufficient coverage of the interferometric (u,v)-plane is available. Experiments are in progress; test telescopes have been erected, and trials in connecting large Cherenkov telescopes have been carried out. This paper reviews this interferometric method in view of the new possibilities offered by arrays of air Cherenkov telescopes, and outlines observational programs that should become realistic already in the rather near future.Comment: New Astronomy Reviews, in press; 101 pages, 11 figures, 185 reference

Challenges of Public Housing in a Democratic Nigeria: a Case Study of the Presidential Mandate Housing Scheme

This study examined the challenges of public housing in a democratic Nigeria using the Presidential Mandate Housing Scheme as a case study. Data were derived from purposively selected members of staff of public institutions charged with the responsibility of implementing this scheme in urban areas of Southern Nigeria through interview enquiries and participant observation. These were analyzed using content analysis. The result shows that the scheme was implemented in very few States in Southern part of Nigeria with miniscule number of housing units constructed in those States. Poor programme conception and planning, funding inadequacies and the dearth of preferred building materials were identified as the key challenges that led to the failure of this scheme. The paper argues that despite the return of democratic rule in 1999 and subsequent adoption of the New National Housing and Urban Development Policy in 2002, low organizational capacity of public housing agencies, the lack of collaborations between these agencies and private sector organizations and the none availability of reliable local building materials constitute serious impediments to smooth and successful implementation of public housing programmes in Nigeria. It therefore suggests that the prospects of public housing in democratic Nigeria are contingent upon addressing these challenge

Biometrics

Biometrics-Unique and Diverse Applications in Nature, Science, and Technology provides a unique sampling of the diverse ways in which biometrics is integrated into our lives and our technology. From time immemorial, we as humans have been intrigued by, perplexed by, and entertained by observing and analyzing ourselves and the natural world around us. Science and technology have evolved to a point where we can empirically record a measure of a biological or behavioral feature and use it for recognizing patterns, trends, and or discrete phenomena, such as individuals' and this is what biometrics is all about. Understanding some of the ways in which we use biometrics and for what specific purposes is what this book is all about

Spaceborne monitoring of high temperature volcanic thermal features: studies using the ERS Along Track Scanning Radiometer

Satellite-based instruments have long been suggested as suitable for monitoring thermal phenomena occurring at the surface of active volcanoes. Past studies using data from high spatial resolution instruments indicated the effectiveness of this technique, but such data are expensive, time-consuming to obtain, and offer a poor temporal resolution. This thesis uses data from the European Remote Sensing satellites’ Along Track Scanning Radiometer (ATSR) to analyse infrared thermal emittance from a variety of volcanic thermal features at low spatial resolution (1 km2) but high temporal resolution (~ 3 days), with data from vegetation fires also being investigated. I calibrate the (previously uncalibrated) 1.6 μm channel of ATSR-1, and go onto show how nighttime data in this waveband can be used to characterise emittance from high temperature surfaces, even if these are significantly smaller than the ATSR pixel size. Procedures are developed to detect hotspots in ATSR data, filter out cloud contaminated observations, and quantitatively analyse the measurements of infrared thermal flux. ATSR time-series datasets are then used to study thermal emittance from active lava domes at Lascar Volcano (Chile) and Unzen Volcano (Japan), with volcanological interpretations being made from the observed variations in radiance. At both volcanoes the dominant source of nighttime shortwave infrared thermal flux is found to be high temperature surfaces heated by fumarolic degassing. During the monitoring period, decreases in shortwave infrared flux indicate an increased hazard at Lascar, such a change indicating blockage of the degassing system and an increased likelihood of a major pressure-driven explosive event. The reverse is found to be true at Unzen, where increases in shortwave infrared flux are found to be generally related to increases in magma supply (both being positively correlated with the flux rate of magmatic gas) and so to an increased frequency of hazardous pyroclastic flow from the growing dome. ATSR time-series studies of active lava flows at Fernandina Volcano (Galápagos Islands) and Mount Etna (Sicily) indicate that such data can also be used to document the thermal evolution of a developing lava flow field. Though necessitating assumptions regarding the flow-field thermal structure, ATSR-based estimates of the area of emplaced lava compare favourably with those obtained using higher spatial resolution imagery. For the 1991 - 1993 Etna flow, the estimates of flow surface temperature and area are used to investigate the importance of the various heat loss mechanisms. Results indicate that radiative losses dominate, but that basal conduction is also highly significant. The Moderate Resolution Imaging Spectrometer (MODIS) of NASA’s Earth Observing System (EOS) will soon provide a new source of multi-waveband, high temporal resolution data, available to the general volcanological and remote sensing community via the EOSDIS data network. I recommend that consideration be given to nighttime operation of the MODIS shortwave infrared channels, since studies using ATSR suggest that these data have considerable potential for the thermal monitoring of active volcanoes