- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A novel compact dual-mode SIW filter with wide rejection band and selective response
摘要： A compact dual-mode substrate-integrated waveguide (SIW) bandpass filter with wide upper stopband is presented. A cross shaped slot is etched on the top plane of SIW cavity to alter the second mode (TE201) current distribution and move it closer to the first mode (TE101), to enhance the bandwidth flatness. Removing few via near the excitation ports, provides longer path for the current to resonance and give us the transmission zeros in a simple way. Another 2 TZs are used to improve the stopband by suppressing higher order modes resonances. The designed filter is fabricated and tested and a very good result is achieved to confirm the design idea. There is also a good agreement between the measured and Full Wave simulated results. The fabricated sample realizes a fractional bandwidth of 9.1% at 7.5 GHz center frequency and 2 zeros at 12.5 GHz and 15 GHz.
关键词： dual-mode filter,substrate-integrated waveguide (SIW),coplanar waveguide (CPW),transmission zero
更新于2025-09-10 09:29:36
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[IEEE 2018 9th International Conference on Computing, Communication and Networking Technologies (ICCCNT) - Bangalore (2018.7.10-2018.7.12)] 2018 9th International Conference on Computing, Communication and Networking Technologies (ICCCNT) - Visibility Enhancement of Fog Degraded Image Sequences on SAMEER TU Dataset Using Dark Channel Strategy
摘要： Image sequences captured in poor visibility condition especially in foggy weather severely affect the scene structure of an image, which in turn will affect several computer vision applications like remote sensing, intelligent vehicles, and visual surveillance detection, tracking, and recognition of targets. Thus, retrieving back the clear scene from such foggy image sequences is of great importance. The main focus of this paper is to summarize current image dehazing algorithms and also implement a robust technique for increasing the visibility of the fog degraded image sequences. In this paper, we investigated different dehazing methods and classified them. After investigation of different dehazing approaches, we deeply analyze Dark Channel Prior Technique(DCP) and implemented this technique on Benchmark and on our own developed Dataset called SAMEER TU(Society of Applied Microwave Electronics Engineering & Research-Tripura University) Dataset on images and videos. Experimental results demonstrate that this algorithm is efficient which can restore the contrast and color of the scene effectively, and thereby improves the visibility of the image. Finally, to identify the robustness of the technique used, we used different objective image quality assessment methods. Finally, we propound the problems of defogging approaches which need to be further studied.
关键词： Transmission map,depth estimation,image sequences restoration,dehazing
更新于2025-09-10 09:29:36
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[IEEE 2018 International Conference on Smart Electric Drives and Power System (ICSEDPS) - Maharashtra State, India (2018.6.12-2018.6.13)] 2018 International Conference on Smart Electric Drives and Power System (ICSEDPS) - Cascaded H-Bridge Inverter based PV-STATCOM
摘要： The environmental effect and need of energy have been increasing rapidly, due to this demand for renewable resources increased. One of the renewable resources Solar Photovoltaic (PV) energy is presently most popular in the environment. An inverter is a necessary part of grid-connected PV systems. This paper presents a new approach of large-scale photovoltaic solar farm inverter as STATCOM, known as PV-STATCOM, for regulation of voltage at the point of common coupling which recovers the voltage stability of the transmission line. Over daytime, the solar PV farm generates active power, but stay in idleness at the night-time. In this paper, PV-STATCOM incorporating multilevel inverter is presented. The voltage at the PCC is regulated at different loading conditions using PV-STATCOM. The entire system modeling and study are performed using MATLAB/SIMULINK.
关键词： STATCOM,photovoltaic(PV),cascaded H-Bridge (CHB),flexible AC transmission system (FACTS),Pulse width modulation (PWM),neutral point clamped (NPC)
更新于2025-09-10 09:29:36
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Determination of Sulfite in Botanical Medicine Using Headspace Thin-Film Microextraction and Surface Enhanced Raman Spectrometry
摘要： A facile method using headspace thin-film microextraction (HS-TFME) coupled with surface enhanced Raman spectrometry (SERS) has been developed for the determination of sulfite in traditional Chinese herbal medicine. The extraction substrate was synthesized by depositing urchin-like ZnO micron particles on glass sheets using chemical liquid phase deposition. Under the optimal conditions, the intensity of the SERS signal at 630–640 cm?1 provided a good linear relationship with the concentration of sulfite from 25 to 400 mg/kg, and the linear correlation coefficient (R) was 0.996 with a detection limit of 6 mg/kg. The method was employed for the determination of sulfite in herbal medicines, and the results were confirmed by a traditional distillation-titration method. Therefore, this developed HS-TFME-SERS method may play an important role in the rapid, simple, and selective determination of sulfite residues in Chinese herbal medicine and become a potentially universal method for this analyte in various solid samples.
关键词： Headspace thin-film microextraction (HS-TFME),scanning electron microscopy (SEM),X-ray diffraction (XRD),surface enhanced Raman spectrometry (SERS),transmission electron microscopy (TEM)
更新于2025-09-10 09:29:36
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Enhanced sensitivity of hemoglobin sensor using dual-core photonic crystal fiber
摘要： A Hemoglobin (Hb) biosensor based on dual-core photonic crystal fiber is proposed and analyzed. In this paper, the effective refractive index dependency on the Hb concentration within a blood sample is utilized in obtaining the transmission spectrum variation. The results are calculated using full vectorial finite element method. Through this study, the effect of the structure geometrical parameters on the sensor performance is optimized to maximize the sensor sensitivity. The numerical results show a sensitivity of 8.013 nm/g/dL for the X-polarized mode at 3.7 cm fiber length and 7.68 nm/g/dL for the Y-polarized mode at 3.2 cm fiber length of the proposed sensor.
关键词： Coupling length,Finite element method,Transmission spectrum,Dual-core photonic crystal fiber,Hemoglobin concentration
更新于2025-09-10 09:29:36
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Real-time observation of the temperature-induced phase transformation in GeTe and its thermal expansion properties
摘要： The GeTe-based system has long been considered as a promising candidate system for various functional applications; many of which are directly related to the polymorphic phase transformation in their crystalline forms. Consequently, the microstructure underlying their intriguing phase transition has been the subject of numerous studies. Here we provide real-time observation of the microstructural changes associated with the reversible pseudo-cubic (or rhombohedral) to cubic GeTe phase transition using high-voltage transmission electron microscopy (HV-TEM) operating at 1,250kV and complementary high-temperature X-ray diffraction (XRD). As a result of the phase transition, the pseudo-cubic GeTe domain’s configuration significantly changes from its original band-like to a spike-like morphology with a different orientation after a heating/cooling cycle. The coefficients of thermal expansion (CTE) properties as a function of temperature are also explored in relation to the GeTe phase transition.
关键词： CTE ellipsoids,in-situ high voltage transmission electron microscopy,GeTe,thermal expansion tensor,ferroelectric domains
更新于2025-09-10 09:29:36
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Unidirectional Absorption in a Three-Dimensional Tunable Absorber Under Oblique Incidence
摘要： In this paper, we propose a three-dimensional tunable absorber to realize a controllable unidirectional absorption and unidirectional transmission based on the plasma metamaterial, which includes two metamaterial layers that are vertical to each other. Each side of the proposed absorber integrates two split-ring resonators, which are made in the solid-state plasma (SSP). Unidirectional absorption and unidirectional transmission can be achieved when the incident angle of the electromagnetic wave is 30°. Furthermore, the unidirectional absorption and unidirectional transmission can be manipulated through exciting the different SSP resonators and adjusting the positions of the corresponding gaps between the two SSP resonators. In addition, the tunable absorption and transmission spectra can be obtained when the different SSP resonators are excited.
关键词： Unidirectional transmission,Plasma metamaterial,Unidirectional absorption
更新于2025-09-10 09:29:36
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[IEEE 2018 International Conference on Smart Computing and Electronic Enterprise (ICSCEE) - Shah Alam, Malaysia (2018.7.11-2018.7.12)] 2018 International Conference on Smart Computing and Electronic Enterprise (ICSCEE) - Energy Harvesting For Efficient 5G Networks
摘要： The design of traditional mobile wireless network emphasises on large capacity as well as ubiquitous access. However, environmental protection and energy saving may soon become inevitable trends due to rising global demands. In the wireless networking field, researchers should shift their focus towards efficient networks and energy harvesting (EH). In this work, we consider energy efficiency and EH to address the issue of energy shortage, which also represents the ratio of the quantity of data that have been transferred to the dissipated energy within the system, simultaneously. The simulation-based mathematics signifies the relation between energy efficiency ((cid:2159)(cid:2161)(cid:4667) against the training interval ((cid:2176)(cid:2202)(cid:4667) and how the energy efficiency is impacted by the change in block size and number of users.
关键词： 5G,Wireless Communication,Resource Allocation,Energy Harvesting(EH),Information Decoding(ID),Green Transmission,Networking
更新于2025-09-10 09:29:36
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Effect of the reaction medium on the characteristics of silanized titanium dioxide particles: Differences obtained in the Zeta potential data and infrared spectra
摘要： In this document we present the differences in the Zeta potential and in the Infrared spectra data obtained from the characterization of silanized titanium dioxide particles, using two different solvents as reaction media: ethanol and toluene. Also, we provide micrographs of transmission electron microscopy in order to show morphological differences between the analyzed samples.
关键词： Zeta Potential Figure,Fourier Transformed Infrared Figure,Colloid and Surface Chemistry,Chemical Engineering,Transmission Electron Microscope images
更新于2025-09-10 09:29:36
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Optical transparency and electrical conductivity of intermediate filaments in Müller cells and single-wall carbon nanotubes
摘要： Presently we investigated the electrical conductivity and optical transparency of Müller cell intermediate filaments. For comparison, the same properties were also explored in the model system of single-wall carbon nanotubes. We report the method of separation and purification of porcine (Sus scrofa domestica) intermediate filaments, extracted from the retinal Müller cells. We also report experimental and theoretical methods of measurements and calculations of the resistivity and light transmission yield by the intermediate filaments and single wall carbon nanotubes. The measured resistivity values were (4.7 ± 0.3) × 10?4 Ω?m?1?cm2 and (2.8 ± 0.2) × 10?4 Ω?m?1?cm2 at 5 °C (278 K), for the intermediate filaments and single wall carbon nanotubes, respectively, being quite close to those of typical metals. We report a method for measuring the light energy transmission by these nanostructures. We found that they efficiently transfer excitation energy along their axis, with the light reemitted at their other end. The measured yields of transferred light energy were 0.50 ± 0.03 and 0.26 ± 0.02 for intermediate filaments and single wall carbon nanotubes, respectively (λexc = 546.1 nm; T = 288 K). The reported results are novel, providing a direct confirmation of the earlier proposed quantum mechanism of light energy transport in the inverted retina of vertebrates. Our data also show that Müller cell intermediate filaments, in addition to their cytoskeletal function, are capable of providing for the light energy transfer within the inverted retina. The data obtained enable a significant progress in our understanding of the high-contrast vision of the vertebrate eyes. The most important conclusion of the current study is the discovery of light energy propagation along natural biological nanofibers (intermediate filaments). This result is completely novel and unique, being reported for the first time.
关键词： Müller cell,Intermediate filament,Porcine retina,Light transmission,Electric conductivity
更新于2025-09-10 09:29:36