379 research outputs found

    Improvement of PolSAR Decomposition Scattering Powers Using a Relative Decorrelation Measure

    Full text link
    In this letter, a methodology is proposed to improve the scattering powers obtained from model-based decomposition using Polarimetric Synthetic Aperture Radar (PolSAR) data. The novelty of this approach lies in utilizing the intrinsic information in the off-diagonal elements of the 3×\times3 coherency matrix T\mathbf{T} represented in the form of complex correlation coefficients. Two complex correlation coefficients are computed between co-polarization and cross-polarization components of the Pauli scattering vector. The difference between modulus of complex correlation coefficients corresponding to Topt\mathbf{T}^{\mathrm{opt}} (i.e. the degree of polarization (DOP) optimized coherency matrix), and T\mathbf{T} (original) matrices is obtained. Then a suitable scaling is performed using fractions \emph{i.e.,} (Tiiopt/i=13Tiiopt)(T_{ii}^{\mathrm{opt}}/\sum\limits_{i=1}^{3}T_{ii}^{\mathrm{opt}}) obtained from the diagonal elements of the Topt\mathbf{T}^{\mathrm{opt}} matrix. Thereafter, these new quantities are used in modifying the Yamaguchi 4-component scattering powers obtained from Topt\mathbf{T}^{\mathrm{opt}}. To corroborate the fact that these quantities have physical relevance, a quantitative analysis of these for the L-band AIRSAR San Francisco and the L-band Kyoto images is illustrated. Finally, the scattering powers obtained from the proposed methodology are compared with the corresponding powers obtained from the Yamaguchi \emph{et. al.,} 4-component (Y4O) decomposition and the Yamaguchi \emph{et. al.,} 4-component Rotated (Y4R) decomposition for the same data sets. The proportion of negative power pixels is also computed. The results show an improvement on all these attributes by using the proposed methodology.Comment: Accepted for publication in Remote Sensing Letter

    Developmental research of sustainable technologies to minimise problematic road embankment settlements

    Get PDF
    Challenging, problematic and non-uniform ground conditions are a night mare to geotechnical engineers tasked with the design and construction of buildings and transport infrastructure. These often suffer undesirable structural settlements. Designing within the current understanding of geotechnics; settlement in peat and organic soils need to be recognised to include the known “primary and secondary consolidation characteristics” and the lesser known “tertiary consolidation phase”. These eventually contribute cumulatively to the consequential uneven and hazardous “bumpy road” surfaces. Undulating flexible road pavements result primarily from the transference of the heavy self-weight of the embankment fill to yielding and non-uniform subgrade. The adoption of conventional design/repair methods such as pile, vertical drain, soil replacement and soil stabilisation are expensive and inappropriate in very soft ground conditions. These then lead to unjustifiably high and repetitive maintenance costs. There being no one quick fix solution for all; pragmatic research must necessarily identify the best/progressively improved practical and sustainable solution. A viable solution is to develop criteria and explore the concept of a “masonry arch bridge structure/lintel-column structure” and adopting sustainable materials through pragmatic searching for appropriate recyclable waste materials. This will lead to the basis for a sustainable, innovative, strong, stiff, permeable composite mat structure that can be used on soft and/or yielding ground conditions. Conceptual lightweight fill technology including the popularly used expanded polystyrene (EPS) and the innovative composite mats recently being developed by the research team are outlined

    A New Biometric Template Protection using Random Orthonormal Projection and Fuzzy Commitment

    Full text link
    Biometric template protection is one of most essential parts in putting a biometric-based authentication system into practice. There have been many researches proposing different solutions to secure biometric templates of users. They can be categorized into two approaches: feature transformation and biometric cryptosystem. However, no one single template protection approach can satisfy all the requirements of a secure biometric-based authentication system. In this work, we will propose a novel hybrid biometric template protection which takes benefits of both approaches while preventing their limitations. The experiments demonstrate that the performance of the system can be maintained with the support of a new random orthonormal project technique, which reduces the computational complexity while preserving the accuracy. Meanwhile, the security of biometric templates is guaranteed by employing fuzzy commitment protocol.Comment: 11 pages, 6 figures, accepted for IMCOM 201

    A Formal Study of the Privacy Concerns in Biometric-Based Remote Authentication Schemes

    Get PDF
    With their increasing popularity in cryptosystems, biometrics have attracted more and more attention from the information security community. However, how to handle the relevant privacy concerns remains to be troublesome. In this paper, we propose a novel security model to formalize the privacy concerns in biometric-based remote authentication schemes. Our security model covers a number of practical privacy concerns such as identity privacy and transaction anonymity, which have not been formally considered in the literature. In addition, we propose a general biometric-based remote authentication scheme and prove its security in our security model

    Supercapacitors Based On Patronite-reduced Graphene Oxide Hybrids: Experimental And Theoretical Insights

    Get PDF
    Here we report the hydrothermal synthesis and detailed study on supercapacitor applications of a patronite hybrid, VS4/reduced graphene oxide, which showed an enhanced specific capacitance of similar to 877 F g(-1) at a current density of 0.5 A g(-1). In comparison to bare vanadium sulfide and reduced graphene oxide, the hybrid showed similar to 6 times and similar to 5 times higher value of specific capacitance, respectively. The obtained energy density (117 W h kg(-1)) and power density (20.65 kW kg(-1)) are comparable to those of other reported transition metal sulfides and their graphene hybrids. Theoretical calculations using density functional theory confirm an enhanced quantum capacitance of VS4/graphene composite systems, owing primarily to the shifting of the graphene Dirac cone relative to the band gap of VS4. The results infer that the hybrid has the potential to be used as a high performance supercapacitor electrode.3371887418881DST (Government of India)DST-SERB [SB/FTP/PS-065/2013]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Ramanujan Fellowship [SR/S2/RJN-21/2012]Department of Science and Technology (DST-SERB), Govt. of India [SR/S1/IC-04/2012]Interconnect Focus Center (MARCO program)State of New YorkNational Science Foundation (NSF) Integrative Graduate Education and Research Traineeship (IGERT) program [0333314]Indo-US Science and Technology Forum (IUSSTF) through a joint INDO-US centre grantMinistry of Human Resources Development (MHRD), India through a center of excellence gran

    EFFECT OF BIOFERTILIZER,VERMICOMPOST AND PHOSPHATE FERTILIZER ON GROWTH AND YIELD OF CAULIFLOWER( Brassica oleraceae Var.botrytis)

    Get PDF
    A field experiment was carried out at Agricultural Researchs and the Experiments Station in Wasit province during 2019-2020 season. This study was aimed to investigate the effect of three factors, the first being biofertilizer at three levels (without addition , a combination of Bacillus megaterium + Glomus mosseae and complet combination of G. mosseae, Azotobacter chroococcum, B. megaterium and Azospirillum brasilense). the second factor was three levels of vermicompost (without,3,6 Mg ha-1).The third factor included three levels of triple superphosphate (0, 40 and 80%) of the fertilizer recommendation. The treatment were distributed in a factorial experiment according to a randomized complete block design. Results showed that the bilateral interaction between the biofertilizer added in an integrated form and vermicompost at the level of 6 Mg ha-1 had a significant effect on all studied properties, while the triple interaction between the biofertilization treatments added as an integrated combination with 6 Mg h-1 of vermicompost and 80% of the mineral fertilizer recommendation   showed the highest averages for the studied traits (flower disc weight, disc weight with leaves, pink disc diameter, total yield, nitrogen and phosphorous content of fruits), which reached 2.524 kg, 4.353 kg, 35.10 cm, 75.71 Mg ha-1, 4.237%, 0.727% respectively in comparison  to the control treatment that gave the lowest averages in all the above traits, which amounted to (1.081 kg, 1.624 kg, 25.10 cm, 32.43 Mg ha-1, 1.893%, 0.210% ) on the sequence

    The Protective Effect of Field Mint Leaves in Reducing Stomach Ulcer in Rats Induced by Aspirin

    Get PDF
    Background: Stomach mucosal wall erosion is caused by the imbalance of the aggressive factors and mucosal defensive factors due to the common causes such as the side effect of consuming non-steroidal anti-inflammatory drugs. Field mint (Menthaarvensis) leaves have been used as an alternative option to cure and prevent the gastric problems. The aim of this study was to analyze the protective effect of Field mint leaves infusion in reducing stomach ulcer in rats induced by Aspirin.Methods: The experimental study was conducted at Histology Laboratory of Faculty of Medicine, Universitas Padjadjaran, Bandung. Sixteen rats were divided into 4 groups randomly: group I (control negative group), group II (control positive group, given 90mg/day Aspirin, group III (the treatment group, given 5cc of Field mint leaves infusion and 90 mg Aspirin) and group IV (the treatment group, given 5.6µg of Misoprostol and 90 mg Aspirin). Mucosal wall erosions were determined by using microscope. Data were analyzed using non-parametric Kruskal-Wallis test and Mann-Whitney U-test (CI 95% and p-value<0.05)Results: Group II had high score of mucosal wall erosions after given only aspirin. In group III and IV, the score of mucosal wall erosions were low. However there was no difference in score of mucosal wall erosions between group III-IV (p<0.05)Conclusions: Field mint (Menthaarvensis) leaves infusion is able to prevent stomach mucosal wall erosions induced by Aspirin as misoprostol does. DOI: 10.15850/amj.v2n3.49

    Signal specific electric potential sensors for operation in noisy environments

    Get PDF
    Limitations on the performance of electric potential sensors are due to saturation caused by environmental electromagnetic noise. The work described involves tailoring the response of the sensors to reject the main components of the noise, thereby enhancing both the effective dynamic range and signal to noise. We show that by using real-time analogue signal processing it is possible to detect a human heartbeat at a distance of 40 cm from the front of a subject in an unshielded laboratory. This result has significant implications both for security sensing and biometric measurements in addition to the more obvious safety related applications

    Impact of remittances on economic growth in developing countries: The role of openness

    Get PDF
    The paper examines the empirical relationship between remittances and economic growth for a sample of 62 developing countries over the time period 1990–2014. Remittances seem to promote growth only in the ‘more open’ countries. That is because remittances are in themselves not sufficient for growth. The extent of the benefit depends on domestic institutions and macroeconomic environment in the receiving country. Unlike the ‘less open’ countries, ‘more open’ countries have better institutions and better financial markets to take advantage of the remittances income and channelise them into profitable investments which, in turn, accelerates the rate of economic growth in these countries.N/
    corecore