Literatura científica selecionada sobre o tema "Dense phased array"

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Artigos de revistas sobre o assunto "Dense phased array"

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Khalil, Diaa. "Cascaded multimode interference phased array structures for dense wavelength division multiplexing applications". Optical Engineering 43, n.º 5 (1 de maio de 2004): 1060. http://dx.doi.org/10.1117/1.1695404.

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Turnbull, Daniel H., Paul K. Lum, Andrew T. Kerr e F. Stuart Foster. "Simulation of B-Scan Images from Two-Dimensional Transducer Arrays: Part I - Methods and Quantitative Contrast Measurements". Ultrasonic Imaging 14, n.º 4 (outubro de 1992): 323–43. http://dx.doi.org/10.1177/016173469201400401.

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Recently, theoretical investigations of the beamforming capability of two-dimensional (2-D) transducer arrays have characterized the array parameters required to steer a symmetrically focused ultrasound beam up to 45° off-axis. These investigations have also shown that the number of elements in a steered 2-D array can be dramatically reduced by using a sparse set of elements, randomly distributed throughout the aperture of the transducer. The penalty paid for the use of a sparse array is the development of a “pedestal” sidelobe in the beam profile, the amplitude of which increases as the number of elements in the array decreases. In this paper the potential of 2-D arrays for medical imaging is assessed by simulating B-scan images of spherical lesions, both cystic and scattering, embedded in a large random scattering volume. Similar contrast characteristics over a range of cyst sizes are demonstrated for a dense 2-D array and a sparse array with 1/8th the number of elements, both operating at 5 MHz. A 32nd order sparse array is shown to perform at a reduced level, producing unacceptable artifactual echoes within images of cysts. The 8th order sparse array pattern has been fabricated on a fixed-focus poly(vinylidene difluoride) transducer using photolithographic, techniques. Experimental images from this transducer are used to verify some of the theoretical predictions made in this paper. Comparisons between simulated B-scan images from linear and 2-D phased arrays are presented in a companion paper.
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Gangfeng, Zheng, Xia Wandong, Wu Xiaoming e Yan Yingchun. "A study of dense-medium cyclone inner-wall abrasion based on ultrasonic phased array technology". Measurement 126 (outubro de 2018): 58–64. http://dx.doi.org/10.1016/j.measurement.2018.05.013.

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Otsuka, Shigenori, Gulanbaier Tuerhong, Ryota Kikuchi, Yoshikazu Kitano, Yusuke Taniguchi, Juan Jose Ruiz, Shinsuke Satoh, Tomoo Ushio e Takemasa Miyoshi. "Precipitation Nowcasting with Three-Dimensional Space–Time Extrapolation of Dense and Frequent Phased-Array Weather Radar Observations". Weather and Forecasting 31, n.º 1 (1 de fevereiro de 2016): 329–40. http://dx.doi.org/10.1175/waf-d-15-0063.1.

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Abstract The phased-array weather radar (PAWR) is a new-generation weather radar that can make a 100-m-resolution three-dimensional (3D) volume scan every 30 s for 100 vertical levels, producing ~100 times more data than the conventional parabolic-antenna radar with a volume scan typically made every 5 min for 15 scan levels. This study takes advantage of orders of magnitude more rapid and dense observations by PAWR and explores high-precision nowcasting of 3D evolution at 1–10-km scales up to several minutes, which are compared with conventional horizontal two-dimensional (2D) nowcasting typically at O(100) km scales up to 1–6 h. A new 3D precipitation extrapolation system was designed to enhance a conventional algorithm for dense and rapid PAWR volume scans. Experiments show that the 3D extrapolation successfully captured vertical motions of convective precipitation cores and outperformed 2D nowcasting with both simulated and real PAWR data.
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Newman, Jennifer F., e Pamela L. Heinselman. "Evolution of a Quasi-Linear Convective System Sampled by Phased Array Radar". Monthly Weather Review 140, n.º 11 (1 de novembro de 2012): 3467–86. http://dx.doi.org/10.1175/mwr-d-12-00003.1.

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Abstract On 2 April 2010, a quasi-linear convective system (QLCS) moved eastward through Oklahoma during the early morning hours. Wind damage in Rush Springs, Oklahoma, approached (enhanced Fujita) EF1-scale intensity and was likely associated with a mesovortex along the leading edge of the QLCS. The evolution of the QLCS as it produced its first bow echo was captured by the National Weather Radar Testbed Phased Array Radar (NWRT PAR) in Norman, Oklahoma. The NWRT PAR is an S-band radar with an electronically steered beam, allowing for rapid volumetric updates (~1 min) and user-defined scanning strategies. The rapid temporal updates and dense vertical sampling of the PAR created a detailed depiction of the damaging wind mechanisms associated with the QLCS. Key features sampled by the PAR include microbursts, an intensifying midlevel jet, and rotation associated with the mesovortex. In this work, PAR data are analyzed and compared to data from nearby operational radars, highlighting the advantages of using high-temporal-resolution data to monitor storm evolution. The PAR sampled the events preceding the Rush Springs circulation in great detail. Based on PAR data, the midlevel jet in the QLCS strengthened as it approached Rush Springs, creating an area of strong midlevel convergence where it impinged on the system-relative front-to-rear flow. As this convergence extended to the lower levels of the storm, a preexisting azimuthal shear maximum increased in magnitude and vertical extent, and EF1-scale damage occurred in Rush Springs. The depiction of these events in the PAR data demonstrates the complex and rapidly changing nature of QLCSs.
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Zribi, Mehrez, Sekhar Muddu, Safa Bousbih, Ahmad Al Bitar, Sat Kumar Tomer, Nicolas Baghdadi e Soumya Bandyopadhyay. "Analysis of L-Band SAR Data for Soil Moisture Estimations over Agricultural Areas in the Tropics". Remote Sensing 11, n.º 9 (11 de maio de 2019): 1122. http://dx.doi.org/10.3390/rs11091122.

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The main objective of this study is to analyze the potential use of L-band radar data for the estimation of soil moisture over tropical agricultural areas under dense vegetation cover conditions. Ten radar images were acquired using the Phased Array Synthetic Aperture Radar/Advanced Land Observing Satellite (PALSAR/ALOS)-2 sensor over the Berambadi watershed (south India), between June and October of 2018. Simultaneous ground measurements of soil moisture, soil roughness, and leaf area index (LAI) were also recorded. The sensitivity of PALSAR observations to variations in soil moisture has been reported by several authors, and is confirmed in the present study, even for the case of very dense crops. The radar signals are simulated using five different radar backscattering models (physical and semi-empirical), over bare soil, and over areas with various types of crop cover (turmeric, marigold, and sorghum). When the semi-empirical water cloud model (WCM) is parameterized as a function of the LAI, to account for the vegetation’s contribution to the backscattered signal, it can provide relatively accurate estimations of soil moisture in turmeric and marigold fields, but has certain limitations when applied to sorghum fields. Observed limitations highlight the need to expand the analysis beyond the LAI by including additional vegetation parameters in order to take into account volume scattering in the L-band backscattered radar signal for accurate soil moisture estimation.
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Connor, L., J. van Leeuwen, L. C. Oostrum, E. Petroff, Y. Maan, E. A. K. Adams, J. J. Attema et al. "A bright, high rotation-measure FRB that skewers the M33 halo". Monthly Notices of the Royal Astronomical Society 499, n.º 4 (30 de setembro de 2020): 4716–24. http://dx.doi.org/10.1093/mnras/staa3009.

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ABSTRACT We report the detection of a bright fast radio burst, FRB 191108, with Apertif on the Westerbork Synthesis Radio Telescope. The interferometer allows us to localize the FRB to a narrow 5 arcsec × 7 arcmin ellipse by employing both multibeam information within the Apertif phased-array feed beam pattern, and across different tied-array beams. The resulting sightline passes close to Local Group galaxy M33, with an impact parameter of only 18 kpc with respect to the core. It also traverses the much larger circumgalactic medium (CGM) of M31, the Andromeda Galaxy. We find that the shared plasma of the Local Group galaxies could contribute ∼10 per cent of its dispersion measure of 588 pc cm−3. FRB 191108 has a Faraday rotation measure (RM) of +474 $\pm \, 3$ rad m−2, which is too large to be explained by either the Milky Way or the intergalactic medium. Based on the more moderate RMs of other extragalactic sources that traverse the halo of M33, we conclude that the dense magnetized plasma resides in the host galaxy. The FRB exhibits frequency structure on two scales, one that is consistent with quenched Galactic scintillation and broader spectral structure with Δν ≈ 40 MHz. If the latter is due to scattering in the shared M33/M31 CGM, our results constrain the Local Group plasma environment. We found no accompanying persistent radio sources in the Apertif imaging survey data.
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Rodriguez-Alvarez, Nereida, Erika Podest, Katherine Jensen e Kyle C. McDonald. "Classifying Inundation in a Tropical Wetlands Complex with GNSS-R". Remote Sensing 11, n.º 9 (4 de maio de 2019): 1053. http://dx.doi.org/10.3390/rs11091053.

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The use of global navigation satellite system reflectometry (GNSS-R) measurements for classification of inundated wetlands is presented. With the launch of NASA’s Cyclone Global Navigation Satellite System (CYGNSS) mission, space-borne GNSS-R measurements have become available over ocean and land. CYGNSS covers latitudes between ±38°, providing measurements over tropical ecosystems and benefiting new studies of wetland inundation dynamics. The GNSS-R signal over inundated wetlands is driven mainly by coherent scattering associated with the presence of surface water, producing strong forward scattering and a distinctive bistatic scattering signature. This paper presents a methodology used to classify inundation in tropical wetlands using observables derived from GNSS-R measurements and ancillary data. The methodology employs a multiple decision tree randomized (MDTR) algorithm for classification and wetland inundation maps derived from the phased-array L-band synthetic aperture radar (PALSAR-2) as reference for training and validation. The development of an innovative GNSS-R wetland classification methodology is aimed to advance mapping of global wetland distribution and dynamics, which is critical for improved estimates of natural methane production. The results obtained in this manuscript demonstrate the ability of GNSS-R signals to detect inundation under dense vegetation over the Pacaya-Samiria Natural Reserve, a tropical wetland complex located in the Peruvian Amazon. Classification results report an accuracy of 69% for regions of inundated vegetation, 87% for open water regions, and 99% for non-inundated areas. Misclassification of inundated vegetation, primarily as non-inundated area, is likely related to the combination of two factors: partial inundation within the GNSS-R scattering area, and signal attenuation from dense overstory vegetation, resulting in a low signal.
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Pedraza, Carlos, Nicola Clerici, Cristian Forero, América Melo, Diego Navarrete, Diego Lizcano, Andrés Zuluaga, Juliana Delgado e Gustavo Galindo. "Zero Deforestation Agreement Assessment at Farm Level in Colombia Using ALOS PALSAR". Remote Sensing 10, n.º 9 (13 de setembro de 2018): 1464. http://dx.doi.org/10.3390/rs10091464.

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Due to the fast deforestation rates in the tropics, multiple international efforts have been launched to reduce deforestation and develop consistent methodologies to assess forest extension and change. Since 2010 Colombia implemented the Mainstream Sustainable Cattle Ranching project with the participation of small farmers in a payment for environmental services (PES) scheme where zero deforestation agreements are signed. To assess the fulfillment of such agreements at farm level, ALOS-1 and ALOS-2 PALSAR fine beam dual imagery for years 2010 and 2016 was processed with ad-hoc routines to estimate stable forest, deforestation, and stable nonforest extension for 2615 participant farms in five heterogeneous regions of Colombia. Landsat VNIR imagery was integrated in the processing chain to reduce classification uncertainties due to radar limitations. Farms associated with Meta Foothills regions showed zero deforestation during the period analyzed (2010–2016), while other regions showed low deforestation rates with the exception of the Cesar River Valley (75 ha). Results, suggests that topography and dry weather conditions have an effect on radar-based mapping accuracy, i.e., deforestation and forest classes showed lower user accuracy values on mountainous and dry regions revealing overestimations in these environments. Nevertheless, overall ALOS Phased Array L-band SAR (PALSAR) data provided overall accurate, relevant, and consistent information for forest change analysis for local zero deforestation agreements assessment. Improvements to preprocessing routines and integration of high dense radar time series should be further investigated to reduce classification errors from complex topography conditions.
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Deka, Suruj S., Sizhu Jiang, Si Hui Pan e Yeshaiahu Fainman. "Nanolaser arrays: toward application-driven dense integration". Nanophotonics 10, n.º 1 (29 de setembro de 2020): 149–69. http://dx.doi.org/10.1515/nanoph-2020-0372.

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AbstractThe past two decades have seen widespread efforts being directed toward the development of nanoscale lasers. A plethora of studies on single such emitters have helped demonstrate their advantageous characteristics such as ultrasmall footprints, low power consumption, and room-temperature operation. Leveraging knowledge about single nanolasers, the next phase of nanolaser technology will be geared toward scaling up design to form arrays for important applications. In this review, we discuss recent progress on the development of such array architectures of nanolasers. We focus on valuable attributes and phenomena realized due to unique array designs that may help enable real-world, practical applications. Arrays consisting of exactly two nanolasers are first introduced since they can serve as a building block toward comprehending the behavior of larger lattices. These larger-sized lattices can be distinguished depending on whether or not their constituent elements are coupled to one another in some form. While uncoupled arrays are suitable for applications such as imaging, biosensing, and even cryptography, coupling in arrays allows control over many aspects of the emission behavior such as beam directionality, mode switching, and orbital angular momentum. We conclude by discussing some important future directions involving nanolaser arrays.
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Teses / dissertações sobre o assunto "Dense phased array"

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Sy, Chérif Hamidou. "Etude des inductances actives intégrées en bande HF/UHF-L et leurs applications potentielles à la radioastronomie". Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2042/document.

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Ce travail de thèse entre dans le cadre de projets nationaux et internationaux de radioastronomie d'une manière générale et en particulier dans celui de SKA (Square Kilometre Array). La conception de circuits intégrés d’applications spécifiques devient de plus en plus importante dans ce domaine. La première étape de ce travail consiste à une étude bibliographique sur les inductances actives intégrées et leurs principales applications dédiées à la radioastronomie. Cette étude a permis de faire un état de l'art. Cet état de l'art a fait ressortir que l'intégration de certaines fonctions s'avère particulièrement difficile voire impossible dès lors que l'utilisation d'une inductance est nécessaire. Ceci est essentiellement dû à la taille importante des inductances. Parmi ces fonctions, nous avons le filtrage, certains types de transceivers, le temps de retard, etc. Or ces fonctions sont très importantes dans une architecture de radiofréquence propre aux réseaux d'antennes phasées. Ce travail de thèse est donc consacré à l'étude et la conception de ces différentes fonctions à l'aide des inductances actives basées sur des topologies à gyrateurs en technologie SiGeC 0,25 μm afin de palier aux problèmes d'intégration. Une des finalités de cette thèse est aussi de montrer que la consommation de ce procédé d'intégration n’est pas si excessive pour ces applications, par rapport à l’utilisation d’inductances localisées intégrées occupant une surface importante sur le substrat. Ce dernier point sera un résultat très important pour les projets où la très haute intégration à bas coût est nécessaire, point clé de réussite des réseaux phasés denses du projet international SKA
This thesis work is part of national and international projects of radio-astronomy in general and in particular that of the SKA (Square Kilometre Array). The design of integrated circuits for specific applications is becoming increasingly important in this field. The first step in this work is a bibliography study on integrated active reactors and their main applications dedicated to radio astronomy. This study allowed making a state of the art. This state of the art has highlighted that the integration of some functions is made especially difficult by the need to use an inductor. This is mainly due to the large size of passive inductors. These functions include the filtering function, some transceivers types, the time delay, etc. But, they are very important in radio-frequency architecture owing to phased array antennas. This thesis propose the study and design of these different functions using active inductors based on gyrators topologies in SiGeC 0.25 μm technology in order to overcome the integration problems. One of the aims of this thesis is to show that the consumption of this integration process is not so excessive for these applications, compared to the use of integrated located inductors occupying a large area on the substrate. This last point is a very important result for projects where high integration at low cost is necessary, key point of the success of dense phased array in the SKA international project
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Mohammad, Afzal. "Low noise amplifier design for dense phased arrays". Thesis, University of Gävle, Department of Technology and Built Environment, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-518.

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Radio Astronomers demand for highly sensitive astronomical facility. Their demand is a radio telescope that can detect the weakest and deepest radio signal. To fulfill the demand of high sensitive telescope, an entirely new way of realizing a radio telescope is required. One of the most important components in the RF front end that determines the sensitivity of a radio telescope is the Low Noise Amplifier (LNA).

The project has the selected process technologies which was searched and about the different noise matching topologies, input matching topology, wide band noise and input matching topologies has discussed by the author to the requirement of LNA in Astronomical purposes.

In this report, the best process technology candidate was chosen apart from selected technology candidates to obtain the minimum noise temperature over broad range frequency upon the modern era of Astronomical LNAs.

The work was continued to design a single ended LNA to obtain desired transistor parameters while using different noise matching topologies, input matching topologies, wideband noise and input matching topologies to have an LNA achievement with the design goal.

Further two stage amplifier was implemented to obtain minimum noise temperature, good stability, high gain, good input and output reflection coefficient with less power consumption.

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Salazar, Cerreno Jorge L. "The feasibility of low-cost, dual-polarized, phase-tilt antenna arrays for dense radar networks". 2012. https://scholarworks.umass.edu/dissertations/AAI3546048.

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This document address the feasibility of low-cost, dual-polarized, X-band phased array antennas for use in dense radar networks for weather surveillance. The “phase-tilt” architecture under investigation combines one-dimensional, electronic beam steering with mechanical actuation (tilting) to achieve a low-cost design capable of rapid, two-dimensional beam positioning without the use of a large scanning pedestal. This architecture is less complex and costly than a full, two-dimensional “phase-phase” array. In addition to meeting requirements for cost, it has the potential to meet requirements for off-axis polarization performance and other key requirements. A prototype antenna already has been designed, fabricated and tested. It defines a new state-of-the-art for remote sensing of weather using small radars. The prototype antenna also serves as a test bed and proof of concept for exploring a potential future network comprised of many antennas arranged in a dense network. This dissertation reviews the current state-of-the-art (in weather radars, dense radar networks, dual-polarized radars, and phased arrays); presents the design, implementation, testing, and validation experiments of the prototype array; and establishes performance requirements for this technology for deployment in future networks of small weather radars.
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Trabalhos de conferências sobre o assunto "Dense phased array"

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Chen-Pang Yeang, Gregory W. Wornell, Lizhong Zheng e James Krieger. "Dense transmit and receive phased arrays". In 2010 IEEE International Symposium on Phased Array Systems and Technology (ARRAY 2010). IEEE, 2010. http://dx.doi.org/10.1109/array.2010.5613250.

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McLaughlin, D. J. "Gap free CONUS surveillance using dense networks of short range radars". In 2010 IEEE International Symposium on Phased Array Systems and Technology (ARRAY 2010). IEEE, 2010. http://dx.doi.org/10.1109/array.2010.5613393.

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Noorishad, Parisa, Stefan J. Wijnholds, Arnold van Ardenne e Thijs M. van der Hulst. "Applicability of Redundancy Calibration on Dense Phased Arrays". In Wide Field Astronomy & Technology for the Square Kilometre Array. Trieste, Italy: Sissa Medialab, 2011. http://dx.doi.org/10.22323/1.132.0035.

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Rebeiz, Gabriel M., Kwang Jin Koh, Tiku Yu, Dongwoo Kang, Choul Young Kim, Yusuf Atesal, Berke Cetinoneri, Sang Young Kim e Donghyup Shin. "Highly dense microwave and millimeter-wave phased array T/R modules and Butler matrices using CMOS and SiGe RFICs". In 2010 IEEE International Symposium on Phased Array Systems and Technology (ARRAY 2010). IEEE, 2010. http://dx.doi.org/10.1109/array.2010.5613364.

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Rebeiz, Gabriel M., Kwang Jin Koh, Tiku Yu, Dongwoo Kang, Choul Young Kim, Yusuf Atesal, Berke Cetinoneri, Sang Young Kim, Kevin Ho e Donghyup Shin. "Highly dense microwave and millimeter-wave phased array T/R modules using CMOS and SiGe RFICs". In 2011 IEEE 12th Annual Wireless and Microwave Technology Conference: An IEEE Industry/ Government/Education Conf. (WAMICON). IEEE, 2011. http://dx.doi.org/10.1109/wamicon.2011.5872903.

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Li, Shuguang, Junwei Ma, Wei Jiang e Wei Hu. "An Automatically Steering Optical Beam-Forming Network for Phased Array Antenna Based on Dense Wavelength Division Multiplexing". In 2018 China International SAR Symposium (CISS). IEEE, 2018. http://dx.doi.org/10.1109/sars.2018.8551970.

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Barnett, Julian, Richard Wilkinson, Alan Kirkham e Keith Armstrong. "Under Pressure Operations on Dense Phase CO2 Pipelines: Issues for the Operator". In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33309.

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National Grid, in the United Kingdom (UK), has extensive experience in the management and execution of under pressure operations on its natural gas pipelines. These under pressure operations include welding, ‘hot tap’ and ‘stopple’ operations, and the installation of sleeve repairs. National Grid Carbon is pursuing plans to develop a pipeline network in the Humber and North Yorkshire areas of the UK to transport dense phase Carbon Dioxide (CO2) from major industrial emitters in the area to saline aquifers off the Yorkshire coast. One of the issues that needed to be resolved is the requirement to modify and/or repair dense phase CO2 pipeline system. Existing under pressure experience and procedures for natural gas systems have been proven to be applicable for gaseous phase CO2 pipelines; however, dense phase CO2 pipeline systems require further consideration due to their higher pressures and different phase behaviour. Consequently, there is a need to develop procedures and define requirements for dense phase CO2 pipelines. This development required an experimental programme of under pressure welding trials using a flow loop to simulate real dense phase CO2 pipeline operating conditions. This paper describes the experiments which involved: • Heat decay trials which demonstrated that the practical limitation for under pressure welding on dense phase CO2 systems will be maintaining a sufficient level of heat to achieve the cooling time from 250 °C to 150 °C (T250–150) above the generally accepted 40 second limit. • A successful welding qualification trial with a welded full encirclement split sleeve arrangement. The work found that for the same pipe wall thickness, flow velocity and pressure, dense phase CO2 has the fastest cooling time when compared with gaseous phase CO2 and natural gas. The major practical conclusion of the study is that for dense phase CO2 pipelines with a wall thickness of 19.0 mm or above, safe and practical under pressure welding is possible in accordance with the existing National Grid specification (i.e. T/SP/P/9) up to a flow velocity of around 0.9 m/s. The paper also outlines the work conducted into the use of the Manual Phased Array (MPA) inspection technique on under pressure welding applications. Finally, the paper identifies and considers the additional development work needed to ensure that a comprehensive suite of under pressure operations and procedures are available for the pipeline operator.
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Jafarlou, Saman, Atabak Rashidian e Mihai Tazlauanu. "Wideband LTCC transitions of flip-chip to waveguides/connectors for a highly dense phased array system-in-package at 60 GHz". In 2017 IEEE/MTT-S International Microwave Symposium - IMS 2017. IEEE, 2017. http://dx.doi.org/10.1109/mwsym.2017.8058984.

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Tsukahara, Shinichiro, Lluis Penalver-Aguila, James Torres e H. Harry Asada. "Design of a Piezoelectric Poly-Actuated Linear Motor". In ASME 2013 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/dscc2013-3983.

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Design and analysis for an efficient and force dense piezoelectric poly-actuated linear motor is presented. A linear motor is constructed with multiple piezoelectric actuator units engaging a rod having gear teeth. The multiple piezo-units are placed along the geared rod with a particular phase difference such that a near constant force is generated regardless of the rod position by coordinating the multiple piezo-units. Rolling contact buckling mechanisms within the piezo-units provide large displacement amplification with high energy transmission and low loss properties from the piezo-units to the geared rod. This piezo-based motor has capacitive actuator characteristics which allow it to bear static loads efficiently. Furthermore, the poly-actuator architecture presented provides for scalability through modular design. First, the basic design principle describing the engagement of buckling amplification mechanisms to a phased array-shaped gear rod is presented, and the resulting force and displacement characteristics are analyzed. Design methods for creating a piezoelectric poly-actuated linear motor are then summarized. A prototype design is presented for which a maximum mean force of 213 N, a maximum velocity of 1.125 m/s, and a force density of 41 N/kg is calculated.
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Xie, Weiqiang, Tin Komljenovic, Jinxi Huang e John Bowers. "Dense III-V/Si Phase Shifters for Optical Phased Arrays". In 2018 Asia Communications and Photonics Conference (ACP). IEEE, 2018. http://dx.doi.org/10.1109/acp.2018.8596249.

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