6,871 research outputs found

    Image-based quantitative analysis of gold immunochromatographic strip via cellular neural network approach

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    "(c) 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works."Gold immunochromatographic strip assay provides a rapid, simple, single-copy and on-site way to detect the presence or absence of the target analyte. This paper aims to develop a method for accurately segmenting the test line and control line of the gold immunochromatographic strip (GICS) image for quantitatively determining the trace concentrations in the specimen, which can lead to more functional information than the traditional qualitative or semi-quantitative strip assay. The canny operator as well as the mathematical morphology method is used to detect and extract the GICS reading-window. Then, the test line and control line of the GICS reading-window are segmented by the cellular neural network (CNN) algorithm, where the template parameters of the CNN are designed by the switching particle swarm optimization (SPSO) algorithm for improving the performance of the CNN. It is shown that the SPSO-based CNN offers a robust method for accurately segmenting the test and control lines, and therefore serves as a novel image methodology for the interpretation of GICS. Furthermore, quantitative comparison is carried out among four algorithms in terms of the peak signal-to-noise ratio. It is concluded that the proposed CNN algorithm gives higher accuracy and the CNN is capable of parallelism and analog very-large-scale integration implementation within a remarkably efficient time

    Damage monitoring in sandwich beams by modal parameter shifts: a comparative study of burst random and sine dwell vibration testing

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    This paper presents an experimental study on the effects of multi-site damage on the vibration response of honeycomb sandwich beams, damaged by two different ways i.e., impact damage and core-only damage simulating damage due to bird or stone impact or due to mishandling during assembly and maintenance. The variation of the modal parameters with different levels of impact energy and density of damage is studied. Vibration tests have been carried out with both burst random and sine dwell testing in order to evaluate the damping estimation efficiency of these methods in the presence of damage. Sine dwell testing is done in both up and down frequency directions in order to detect structural non-linearities. Results show that damping ratio is a more sensitive parameter for damage detection than the natural frequency. Design of experiments (DOE) highlighted density of damage as the factor having a more significant effect on the modal parameters and also proved that sine dwell testing is more suitable for damping estimation in the presence of damage as compared to burst random testing

    Survey and documentation of emerging technologies for the Satellite Power System (SPS)

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    The genesis of the solar power satellite (SPS) concept is reviewed historically and the original assumptions and guidelines which led to development of the SPS reference system design concept are discussed. Some guidelines are applicable to almost any SPS design, but others can be changed, leading to new and perhaps preferable systems. In order to stimulate new SPS concepts and to facilitate comparative assessment of emerging SPS technologies, one useful approach is to break the overall system into functional parts. The system functions which must be performed by any SPS concept and the interrelations between them are discussed and a systematic framework is presented for assessing the wide variety of system concepts and subsystem technologies which have been proposed. About 80 alternative SPS technologies are reviewed

    Development of a Computational Fluid Dynamics Model for Ice Formation: Validation and Parameter Analysis

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    : In the history of civil aircraft transportation, ice formation has been identified as a key factor in the safety of flight. Anti-icing and deicing systems have emerged through the years with the aim to prevent or to eliminate ice formation on wing airfoils, control surfaces and probes. Modern flying machines demand more efficiency in order to reduce the carbon footprint and increase the sustainability of flight transport. In order to achieve this goal, the need to have an efficient aircraft with an efficient and low power consuming system is fundamental. This paper proposes a new model for ice accretion using computational fluid dynamics (CFD). This model permits the simulation of the shape of the ice formed over a profile varying boundary condition (i.e., speed, liquid water content, and so on). The proposed model also takes into account the amount of heat transferred between the water and the surrounding environment and includes the effects of air turbulence on the ice formation process. The CFD simulations have been validated with NASA experimental outcome and show good agreement. The proposed model can be also used to investigate the effects of various parameters such as air speed, liquid water content, and air temperature on the ice formation process. The results evidence that the proposed model can accurately predict ice formation process and is suitable to optimize the design of anti-icing or deicing systems for aircraft and helicopters. This approach is not limited to aerospace but can also be exported to other applications such as transportation, wind turbine, energy management, and infrastructure

    Mars Ascent Vehicle Design for Human Exploration

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    In NASA's evolvable Mars campaign, transportation architectures for human missions to Mars rely on a combination of solar electric propulsion and chemical propulsion systems. Minimizing the Mars ascent vehicle (MAV) mass is critical in reducing the overall lander mass and also eases the requirements placed on the transportation stages. This paper presents the results of a conceptual design study to obtain a minimal MAV configuration, including subsystem designs and mass summaries

    Identification of cascade of Hammerstein models for the description of non-linearities in vibrating devices

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    International audienceIn a number of vibration applications, systems under study are slightly nonlinear. It is thus of great importance to have a way to model and to measure these nonlinearities in the frequency range of use. Cascade of Hammerstein models conveniently allows one to describe a large class of nonlinearities. A simple method based on a phase property of exponential sine sweeps is proposed to identify the structural elements of such a model from only one measured response of the system. Mathematical foundations and practical implementation of the method are discussed. The method is afterwards validated on simulated and real systems. Vibrating devices such as acoustical transducers are well approximated by cascade of Hammerstein models. The harmonic distortion generated by those transducers can be predicted by the model over the entire audio frequency range for any desired input amplitude. Agreement with more time consuming classical distortion measurement methods was found to be good

    Technology requirements for advanced earth orbital transportation systems. Volume 2: Summary report

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    The results of efforts to identify the technology requirements for advanced earth orbital transportation systems are reported. Topics discussed include: (1) design and definition of performance potential of vehicle systems, (2) advanced technology assessment, and (3) extended performance. It is concluded that the horizontal take-off concept is the most feasible system considered

    Quadruple glazing panel filled with PCM and its influence on the sound insulation of building facades

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    The long-term pressure on a properly functioning modern infrastructure is the main reason for the development of new construction elements and technological processes. In the case of buildings, this development can offer original and significant improvements in aesthetic, functional and economical terms. Then the implemented structural elements and technological systems have a major impact on the overall of building quality, and comfort for occupants. Recently, when building structures are becoming lighter and lighter in weight, problems with heat accumulation and poor sound insulation occur. To improve the accumulation properties, production and implementation companies implementing accumulation materials into the buildings most frequently in the form of panels that can be incorporated into the peripheral walls or directly replace them. A subject of this paper is to study the effect of implementation one type of facade system into the perimeter walls on the airborne sound insulation of building facades. The research is dedicated to the quadruple glazing panel which is a translucent wall element without any mechanical components or electronic devices. © 2017, World Scientific and Engineering Academy and Society. All rights reserved.MSMT-7778/2014, MŠMT, Ministerstvo Školství, Mládeže a Tělovýchov

    Behavior and Analysis of Blast-Resistant Precast Concrete Wall Panels with Realistic Boundary Conditions and Openings

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    This dissertation presents a comprehensive assessment of the flexural resistance of non-loadbearing, blast-resistant precast concrete wall panels. A major focus of this research is quantifying the expected response of these panels, considering realistic
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