8,094 research outputs found

    Oscillation-Based Test Structure and Method for OTA-C Filters

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    “This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”This paper describes a design for testability technique for operational transconductance amplifier and capacitor filters using an oscillation-based test topology. The oscillation-based test structure is a vectorless output test strategy easily extendable to built-in self-test. The proposed methodology converts filter under test into a quadrature oscillator using very simple techniques and measures the output frequency. The oscillation frequency may be considered as a digital signal and it can be evaluated using digital circuitry therefore the test time is very small. These characteristics imply that the proposed method is very suitable for catastrophic and parametric faults testing and also effective in detecting single and multiple faults. The validity of the proposed method has been verified using comparison between faulty and fault-free simulation results of two integrator loop and Tow-Thomas filters. Simulation results in 0.25 mum CMOS technology show that the proposed oscillation-based test strategy for OTA-C filters has 87% fault coverage and with a minimum number of extra components, requires a negligible area overhead

    Oscillation-based Test Method for Continuous-time OTA-C Filters

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    “This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”Design for testability technique using oscillation-based test topology for KHN OTA-C filters is proposed. The oscillation-based test structure is a vectorless output test strategy easily extendable to built-in self-test. During test mode, the filter under test is converted into an oscillator by establishing the oscillation condition in its transfer function. The oscillator frequency can be measured using digital circuitry and deviations from the cut-off frequency indicate the faulty behaviour of the filter. The proposed method is suitable for both catastrophic and parametric fault diagnosis as well as effective in detecting single and multiple faults. The validity of the proposed method has been verified using comparison between faulty and fault-free simulation results of KHN OTA-C filter. Simulation results in 0.25mum CMOS technology show that the proposed oscillation-based test strategy has 84% fault coverage and with a minimum number of extra components, requires a negligible area overhead.Final Published versio

    Topological aspect of graphene physics

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    Topological aspects of graphene are reviewed focusing on the massless Dirac fermions with/without magnetic field. Doubled Dirac cones of graphene are topologically protected by the chiral symmetry. The quantum Hall effect of the graphene is described by the Berry connection of a manybody state by the filled Landau levels which naturally possesses non-Abelian gauge structures. A generic principle of the topologically non trivial states as the bulk-edge correspondence is applied for graphene with/without magnetic field and explain some of the characteristic boundary phenomena of graphene.Comment: 12 pages, 8 figures. Proceedings for HMF-1

    Wavefront Analysis for Annular Ellipse Aperture

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    The orthonormal annular ellipse Zernike polynomials are important for wavefront analysis of annular ellipse aperture (elliptical aperture with an elliptical obscuration) for their property of orthgonalization over such aperture and representing balanced aberration. In this paper, the relationship between the Zernike annular ellipse   polynomials and third order Siedel aberrations were studied. Then the standard deviations of balanced and unbalanced primary aberrations have been calculated for this aperture. Keywords: Zernike polynomials, annular ellipse aperture, aberration, standard deviatio

    Implementation of International Instruments in Indonesian Legislation in the Field of Conservation of Fish Resources

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    The intention contained in laws and regulations concerning the conservation of fish resources is so that there are activities that lead to protection of fish resources as a whole. During this time the utilization of fish resources more dominant done compared to the protection and preservation, so the impact on the aquatic ecosystem. The purpose of this research is to examine International agreements regarding the conservation of fish resources which have been ratified and implemented into other policies and legislation in order to become a guideline in behavior so bring a change in society. This research is a descriptive qualitative using a data source from an earlier study results and document the latest libraries. Results of the study that the conditions of the CCRF (Code of Conduct for Responsible Fisheries) became a legal basis in the formulation of the provisions concerning the management of fish resources responsibly. Sustainable fisheries zone were never regulated in the regulation of the management of conservation areas. The Fisheries Act has yet to implement the provisions of the UN fish stocks agreement of 1995 relating to the conservation and management of fish resources in the ZEE and Indonesia on the high seas. Therefore the Fisheries Act require refinement, considering Indonesia has been a member of two regional fisheries management organization and ratify the UNITED NATIONS Agreement on fish stocks of 1995

    Anisotropy of Resonant Inelastic X-Ray Scattering at the K Edge of Si:Theoretical Analysis

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    We investigate theoretically the resonant inelastic x-ray scattering (RIXS) at the KK edge of Si on the basis of an ab initio calculation. We calculate the RIXS spectra with systematically varying transfered-momenta, incident-photon energy and incident-photon polarization. We confirm the anisotropy of the experimental spectra by Y. Ma {\it et al}. (Phys. Rev. Lett. 74, 478 (1995)), providing a quantitative explanation of the spectra.Comment: 18 pages, 11 figure

    EFFECT OF PHYSICOCHEMICAL PROPERTIES OF EMULSIONS FORMED BY SELF-EMULSIFYING DRUG DELIVERY SYSTEMS (SEDDS) ON THE SOLUBILIZATION STATE OF DRUG: IN VITRO STUDY

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    Objective: Parameters in the oil pre-concentrate which can affect the solvent capacity of the resultant dispersion such as, oil-cosurfactant ratio, type of surfactant used in the system, the inclusion of water soluble co-solvents and the solubilization capacity of native surfactants such as, bile salts and lecithin were studied in an attempt to circumvent crystallization of drug during its passage in the gut.Methods: Different types of self-emulsifying systems representing type II, IIIA and IIIB, were used to probe the influence of the various physicochemical properties of the resultant dispersions on the fate of dissolved model lipophilic drug. This was achieved by studying emulsification behavior of lipid systems in fed and fasted biological fluids, analyzing solubilization/drug crystallization kinetics and oil droplet diameter measurement.Results: Self-micro-emulsifying lipid systems lost solvent capacity on dispersion and were not able to keep the drug in solution at equilibrium. Miglyol 812/Imwitor ratio in the pre-concentrate mixture appeared to influence the kinetics of drug crystallization. Pre-microemulsion systems containing Tagat TO dispersions were found to hold more drugs in solution at equilibrium than in the case of systems containing Cremophor RH40. The inclusion of as little as 10-20% PEG in the lipid mixture accelerated drug precipitation. Bile salt-lecithin mixed micelles appears to some extent enhance the solubilization capacity of these systems after dispersionConclusion: Solvency of emulsions formed by self-emulsifying drug delivery in various emulsification media is a crucial parameter influencing the fate of dissolved drug after the dispersion of the formulations

    ROLE OF HYDROPHILIC SURFACTANTS IN THE EMULSIFICATION MECHANISTICS OF TYPE III SELF-MICRO-EMULSIFYING DRUG DELIVERY SYSTEMS (SMEDDS)

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    Objective: Evaluation of the self-emulsifying behaviour of type III lipid systems comprising mixed medium chain glycerides (Miglyol 812-Imwitor 988) and wide range of hydrophilic surfactants in an attempt to identify self-emulsifying microemulsion formulations, prevaricate the crystallization tendency of Cremophor RH40 in the pre-microemulsion concentrate, to shed some light on the mechanistic behavior of these systems after aqueous dispersion. Methods: Non-ionic surfactants with HLB in the range 14 to 16.5 are investigated amongst these are; Cremophor RH40, Cremophor EL, Crillet 4 (polysorbate 80), Crillet 1 (polysorbate 20) and Tagat O2. Optimum oil blends of Miglyol 812-Imwitor 988 and various non-ionic surfactant systems were verified using self-emulsification performance studies, oil droplet diameter measurements and dynamic equilibrium phase studies. Results: Oil blends of Miglyol 812 as an oil and Imwitor 988 as a cosurfactant were optimized for microemulsion systems at ratios of 1:1 in the case of Cremophor RH40 or EL, and at 2:3 in the case of Crillet 4 or Tagat O2. In order to obtain small droplet size and fast dispersion rate for type III lipid systems, hydrophilic surfactants with HLB values between 13 and 15 were found to be the optimum. Conclusion: Spontaneous micro-emulsification in type III lipid system was attributed to the “diffusion and stranding” theory. Yet, the formation of liquid crystalline phases as intermediate phases during dilution of the oil formulation with water appears to be quintessential for the mechanistics of emulsification regardless type of lipid class system
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