This paper presents a correction algorithm for metal artefacts in CT images using a novel technique known as dual-step adaptive thresholding (DSAT). The proposed artefact correction algorithm was applied to selected a...
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This paper presents a correction algorithm for metal artefacts in CT images using a novel technique known as dual-step adaptive thresholding (DSAT). The proposed artefact correction algorithm was applied to selected artefactual phantom and clinical CT images. The missing projection data due to metal is detected and extracted by double-thresholding technique. The DSAT-based algorithm allows significant reduction of the artefact and preserves most of the anatomical structures in the corrected CT images.
In this research, our research team used the self-designed piezoelectric actuator to achieve the micro/nanometer level precise positioning biaxial piezoelectric actuated stage through the redesign of stage mechanism. ...
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In the highway environment, many applications require localization. It is common to use the Global Positioning system (GPS) to find the current position, but GPS is easily influenced by the external environment and ha...
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This paper is to perform an experimental and numerical study on the various arrangements of cuboids transversely installed in the side of field plates and then to investigate how the flow characteristics and the heat ...
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An analysis of the radar backscattering from the ocean surface covered by oil spill is presented using a mi- crowave scattering model and Monte-Carlo simulation. In the analysis, a one-dimensional rough sea sur- face ...
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An analysis of the radar backscattering from the ocean surface covered by oil spill is presented using a mi- crowave scattering model and Monte-Carlo simulation. In the analysis, a one-dimensional rough sea sur- face is numerically generated with an ocean waveheight spectrum for a given wind velocity. A two-layered medium is then generated by adding a thin oil layer on the simulated rough sea surface. The electric fields backscattered from the sea surface with two-layered medium are computed with the method of moments (MoM), and the backscattering coefficients are statistically obtained with N independent samples for each oil-spilled surface using the Monte-Carlo technique for various conditions of surface roughness, oil-layer thickness, frequency, polarization and incidence angle. The numerical simulation results are compared with theoretical models for clean sea surfaces and SAR images of an off-spilled sea surface caused by the Hebei (Hebei province, China) Spirit oil tanker in 2007. Further, conditions for better oil spill extraction are sought by the numerical simulation on the effects of wind speed and oil-layer thickness at different inci- dence angles on the backscattering coefficients.
This paper proposes a system composed of hardware and software components that facilitates the activity of wardriving and assists in collecting statistical data by GPS of WiFi networks and their security status in par...
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Content synchronization in LMS (Learning Management system) is a new area of research which involves the transfer of data from one machine to another. Many researchers have conducted their researches concerning synchr...
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Content synchronization in LMS (Learning Management system) is a new area of research which involves the transfer of data from one machine to another. Many researchers have conducted their researches concerning synchronization in different applications on data transfer. Therefore, in this paper we introduce a new idea of synchronization in heterogeneous LMSs and to share learning contents among different learning institutions. The major contribution in this paper, is based on the integration of rsync with MAS (Multi-Agent system) in heterogeneous learning management systems (LMSs) environment using SCORM (Sharable Content Object Reference Model), so as different learning institutions in higher education (HE) can seamlessly share learning contents in the different LMSs. Hence, a new model of heterogeneous LMS (HLMS) has been presented for easily sharing of learning contents in Higher Learning Institutions (HLI).
A reverberation chamber,which is a test facility for various electromagnetic compatibility tests,uses a stirrer to generate a uniform electric field inside it. However,a stirrer is a big unit and has difficulties in m...
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A reverberation chamber,which is a test facility for various electromagnetic compatibility tests,uses a stirrer to generate a uniform electric field inside it. However,a stirrer is a big unit and has difficulties in maintenance. This paper adopted an idea of a diffuser from acoustics to overcome the problems of a stirrer and presents a substitution effect of a diffuser for a stirrer. To validate the substitution effect of a diffuser,a diffuser and a reverberation chamber for 3.0-5.0 GHz band are designed and fabricated. And the real measurement for analyzing the electric field uniformity in a reverberation chamber is done. The measurement results show that the reverberation chamber with a diffuser satisfies the international standard requirement.
Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF). We calculate these values between the excited states according to the spontaneous ...
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Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF). We calculate these values between the excited states according to the spontaneous transition probabilities using rate equations and the measured intensities of fluorescence spectral lines of He atoms in an electrodeless discharge lamp in the visible spectral region from 350 to 730 nm. The electrodeless discharge lamp with populations in excited states can be used to realize the frequency stabilization reference of the laser frequency standard. This lamp can also build ESFADOFs for submarine communication application in the blue-green wavelength to simplify the system without the use of a pump laser.
Short-term load forecasting can provide information which is applicable for the possible energy interchange with other utilities. Load forecasting is also advantegeous for system security, in fact if applied to the sy...
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