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370 articles for “Resonator”
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Modification of Acrylonitrile-Methylacrylate Copolymer by Gamma Irradiation
Abstract: AbstractRadiative degradation of acrylonitrile-methylacrylate (AM) copolymer has been investigated by electron spin resonance (ESR) and infrared (IR) spectroscopy. The ESR spectrum observed for AM copolymer irradiated to a dose of 12 Mrad is a triplet with an intensity ratio of 1:3:1. The ESR spectrum is simulated by total-curve-fitting method and component spectra are generated. Magnetic parameters of component spectra are evaluated. Component triplet spectrum with magnetic parameters ni=3, mi=1 is …
Published in Journal of Polymer & Composites · Vol. 3, Issue 3, 2015 · pp. 16–19 Read article
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The Transient Response and Frequency Characteristics of Power Transformers having Non-uniform Winding Insulation
Abstract: This paper presents a Laplace-domain distributed-parameter technique for analyzing the transient and frequency response of power transformers having non-uniform winding insulation. Stronger winding insulation near the windings source side terminals is usually applied in order to mitigate the concentration of the transient voltage stresses close to these locations. This will result in a location-dependent inter-turn capacitance distribution. The suggested procedure for analyzing such windings is based on the cascade connection …
Published in Journal of Power Electronics and Power Systems · Vol. 4, Issue 1, 2014 · pp. 37–52 Read article
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The Time and Frequency Response of Shielded Transformer Windings
Abstract: A distributed-parameter model is presented for the transient and frequency analysis of power transformers’ windings in the presence of electrostatic shielding, a technique occasionally applied for improving their initial voltage distribution. The s-domain solution takes into account the windings’ circuit parameters with special emphasis on the additional distributed capacitances between the windings’ conductors and the conducting shield which is connected to the windings’ line terminal. The closeness of the resulting …
Published in Journal of Power Electronics and Power Systems · Vol. 4, Issue 2, 2014 · pp. 33–47 Read article
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An Analytical Method for the Analysis of Transformer Windings Having Non-Uniform Capacitance Distribution
Abstract: A direct procedure for the transient and frequency analysis of transformer windings with location-dependent inter-turn capacitance distribution is presented. This can help simulate windings with non-uniform insulation. The derived analytic solutions in the Laplace domain are based on expressing the non-uniformly-distributed series capacitance per unit length as the sum of a constant term and a variable part proportional to the square of the distance from the winding’s source terminal. The …
Published in Journal of Power Electronics and Power Systems · Vol. 5, Issue 2, 2015 · pp. 41–54 Read article
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The Frequency Characteristics of Transformer Windings Considering the Separation-Dependence of the Inter-Turn Mutual Parameters
Abstract: The paper presents a direct method for the determination of the frequency characteristics of transformer windings. The dependence of both the inter-turn mutual inductances and capacitances on the separation between these winding turns is taken into consideration. From measured data available in the literature, a formula for this dependence is derived. The voltage and current distributions along the winding will be governed by two integro-differential equations in terms of the …
Published in Journal of Power Electronics and Power Systems · Vol. 6, Issue 3, 2016 · pp. 72–81 Read article
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Modeling of Transformer Windings having Non-uniform Inductance Distribution
Abstract: A direct analytical procedure for analyzing power transformer windings with location-dependent series inductance is presented. This dependence is typically introduced in order to take the inter-turn mutual inductive coupling into consideration. The paper addresses the frequency domain analysis conducted in the complex s- or the jω-domains. Results for the frequency-dependent winding’s input impedance with different treatments of the transformer’s neutral point will be available. The frequency characteristics including the resonance …
Published in Journal of Power Electronics and Power Systems · Vol. 4, Issue 3, 2014 · pp. 12–25 Read article
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Case Study of Multipulse Converter System for IGBT Based Inverter in Induction Melting Furnace
Abstract: AbstractHarmonic mitigation is an important aspect for the smooth operation of modern power electronics converters, medical equipment, and home appliances which are generally fed by a common grid supply. In large power equipment such as induction furnaces, it becomes necessary to reduce or eliminate harmonics from the supply. In order to cater dynamic load cycle during complete melting cycles in induction furnaces, power needs to vary. This can be achieved …
Published in Journal of Semiconductor Devices and Circuits · Vol. 4, Issue 1, 2017 · pp. 17–23 Read article
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Design and Validation of Slot Coupled Rectangular Half Mode SIW Antenna
Abstract: This paper presents the design and performance analysis of a Rectangular Half Mode Substrate Integrated Waveguide (HMSIW) antenna configuration to attain higher gain and multiband characteristics with the compact size. It is possible to produce multiband properties by placing variously shaped slots on the top of the patch and ground surface. To attain the necessary gain and multiband resonance characteristics, the type of the slot, dimension optimization, and position optimization …
Published in Journal of Telecommunication, Switching Systems and Networks · Vol. 10, Issue 2, 2023 · pp. 14–21 Read article
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The Impact of MEMS on the Internet of Things (IoT)
Abstract: Our daily lives, workdays, and connections with the external world are all being impacted by theInternet of Things (IoT). Micro Electro-Mechanical Systems (MEMS) are tiny, economical, andpretty accurate sensors that can measure a variety of physical variables, including temperature,pressure, humidity, acceleration, and more. They are a fundamental enabler of this technology. Inthis article, we examine the effects of MEMS on the IoT and the ways in which these incrediblysmall sensors …
Published in Trends in Mechanical Engineering & Technology · Vol. 12, Issue 3, 2022 · pp. 34–38 Read article
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Effects of Variation of Active Region Radius on the Performance Characteristics of a Designed 1550 nm Al0.09Ga0.38In0.53As/InP MQW VCSEL
Abstract: AbstractIn this work, the performance characteristics of a designed Al0.09Ga0.38In0.53As/InP based 1550 nm top emitting multi quantum well (MQW) vertical cavity surface emitting laser (VCSEL) has been obtained. By evaluating the attained result of different parameters of selected MQW VCSEL the peak material gain is obtained as 1652.3 cm-1. For 6.1 mA of injection current and 5.65 µm of active region radius, the optical output power of 31.37 dBm and …
Published in Trends in Opto-electro & Optical Communication · Vol. 4, Issue 3, 2014 · pp. 8–13 Read article
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Performance Analysis of a 1550nm MQW VCSEL by Varying Injection Current
Abstract: AbstractIn this work, the performance of a 1550nm top emitting multi quantum well (MQW) vertical cavity surface emitting laser (VCSEL) has been obtained for the selected quaternary compound In0.53Ga0.47As0.88P0.12 quantum well material the peak material gain is obtained as 1425cm-1. The optical output power of 31.35dBm and the resonance frequency of 5.8GHz are obtained at 6.1mA of injection current. Further by increasing the injection current up to 12mA a maximum …
Published in Trends in Opto-electro & Optical Communication · Vol. 3, Issue 2, 2013 · pp. 25–29 Read article
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Performance Analysis and Optimization of a 1550 nm MQW VCSEL by Varying Differential Gain and Injection Current
Abstract: AbstractIn this work, the performance characteristics of a 1550 nm top emitting multi quantum well (MQW) vertical cavity surface emitting laser (VCSEL) using AlGaInAs/InP are presented. Using this material the peak material gain is obtained as 1652.3 cm-1. A high performance designed VCSEL is obtained with the optimized value of differential gain and injection current. The optical output power of 31.37 dBm and the resonance frequency of 2.5 GHz are …
Published in Trends in Opto-electro & Optical Communication · Vol. 3, Issue 3, 2013 · pp. 31–37 Read article
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Design and Performance Investigation of Silicon-on- Insulator Based Optical Waveguide Biosensor
Abstract: Optical biosensors using silicon on insulator (SOI) prove itself a reliable option to get a real-time and cost-effective breast cancer detection technique. In this article, we discuss the need for and importance of a cancer detection technique that leads to accurate results without posing any harm to patients’ lives. We present a design of an optical biosensor using R-Soft CAD software simulated in the finite difference time domain (FDTD). Applications …
Published in Trends in Opto-electro & Optical Communication · Vol. 13, Issue 2, 2023 · pp. 16–25 Read article
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Design of Triple Band Microstrip Yagi Uda Antenna
Abstract: Abstract A microstrip yagi uda antenna with triple band is proposed in this paper. The design antenna consists of CPW feeding in which the ground plane and the yagi antenna are on the same plane. The resonating frequency of design antenna is 6.29, 7.97 and 9.26 GHz. The antenna had achieved the directivity of 5.232, 5.704 and 6.062 dBi. The impedance of antenna is completely matched at all the three …
Published in Current Trends in Information Technology · Vol. 3, Issue 2, 2013 · pp. 7–10 Read article
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Calculating SAR Distribution and RF Electromagnetic Field Due To MRI Coil at Human Model
Abstract: AbstractMRI (magnetic resonance imaging) is an effective method for diagnosis of diseases. The MRI system is made of some important units including RF (radio frequency) devices [1]. The RF coil is one of the important parts in the RF unit. During the imaging, the RF coil radiates EM (electromagnetic) pulse to the human body and in response receives the NMR (nuclear magnetic resonance) signals emitted from the nuclei, which constitutes …
Published in Journal of Communication Engineering & Systems · Vol. 3, Issue 2, 2013 · pp. 1–8 Read article
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Optimized Performance Characteristics of a 450 nm Semiconductor Laser by Varying Differential Gain
Abstract: AbstractIn this work, the effects on the performance characteristics of a true-blue 3QW separate confinement heterostrcture edge-emitting laser are presented by varying differential gain. At the temperature of 300 K, the threshold current of the laser is . The peak material gain for the designed laser is obtained as and further used for the analysis of the performance characteristics of the designed double-heterostructure laser for the variation of differential gain. …
Published in Journal of Communication Engineering & Systems · Vol. 3, Issue 3, 2013 · pp. 26–35 Read article
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Two Port Ring Shaped DRA Based MIMO (Multiple Input Multiple Output) Antenna for WLAN Application
Abstract: This paper presents multiple input and multiple output (MIMO) antenna which is based on dielectric resonator with very good isolation. This antenna consists of two hybrid resonator and is fed by microstrip feedline through H-Shaped aperture is cut in ground plane just below the Ring DR. Area of this antenna is 40x50 mm². Impedance bandwidth (S11<-10dB) of this antenna is 5.15 to 6.15 GHz. The radiation efficiency and total gain …
Published in Research & Reviews: A Journal of Embedded System & Applications · Vol. 7, Issue 1, 2019 · pp. 17–24 Read article
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Posterior Reversible Encephalopathy Syndrome Secondary to Management of Dimorphic Anemia by Repeated Blood Transfusions: A Case Report
Abstract: Posterior reversible encephalopathy syndrome, popularly known asPRES, is defined as a clinicoradiological syndrome which is characterized by symptoms such as headache, seizures, and altered consciousness and characterized by white matter vasogenic edema affecting the posterior occipital and parietal lobes of the brain .We report a 39-year-old woman who was treated by iron and blood transfusion for dimorphic anemia with a hemoglobin (Hb) level of 2 g/dl. Patient developed three episodes …
Published in Research and Reviews: A Journal of Medicine · Vol. 8, Issue 2, 2018 · pp. 6–8 Read article
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Comparative Analysis of Proposed FCM Clustering Integrated Enhanced Firefly-Optimized Algorithm (En-FAOFCM) for MR Image Segmentation and Performance Evaluation
Abstract: Image segmentation has a significant responsibility in diagnosis and treatment of diseases. To scan patients and determine the severity of certain injuries in hospitals, magnetic resonance imaging (MRI) method is normally used. This paper emphasizes on comparative study of segmentation techniques for segmenting MRI brain images. In this regard, to group the pixels of images in the intensity space, unsupervised clustering techniques are used. Here enhanced firefly algorithm is used …
Published in Journal of Image Processing & Pattern Recognition Progress · Vol. 3, Issue 1, 2016 · pp. 32–44 Read article
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Imaging Technologies in Breast Cancer Screening Beyond Mammography
Abstract: There is a passionate debate in medical world about the best screening method for breast cancer. Early detection is an effective way to diagnose and manage breast cancer. Mammography is the most widely used screening modality, with solid evidence of benefit for women aged 40 to 74 years. Even then it has also undergone increased scrutiny for false-positives with additional testing which increase radiation dose, cost and anxiety. False-negatives with …
Published in Journal of Advances in Shell Programming · Vol. 7, Issue 1, 2020 · pp. 22–32 Read article