1,493,292 research outputs found

    A review of Fixed Bed Gasification Systems for Biomass

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    Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): A review of Fixed Bed Gasification Systems for Biomass. Invited Overview. Vol. IX. April, 2007

    Latest Trends in Automotive Electronic Systems - Highway meets Off-Highway?

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    Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Latest Trends in Automotive Electronic Systems - Highway meets Off-Highway?. Manuscript ATOE 07 012. Vol. IX. July, 2007

    Lecture Notes in Electrical Engineering vol. 365

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    This book includes the original, peer-reviewed research papers from the 2nd International Conference on Electrical Systems, Technology and Information (ICESTI 2015), held during 9–12 September 2015, at Patra Jasa Resort & Villas Bali, Indonesia. The primary objective of this book is to provide references for dissemination and discussion of the topics that have been presented in the conference. This volume is unique in that it includes work related to Electrical Engineering, Technology and Information towards their sustainable development. Engineers, researchers as well as lecturers from universities and professionals in industry and government will gain valuable insights into interdisciplinary solutions in the field of Electrical Systems, Technology and Information, and its applications. The topics of ICESTI 2015 provide a forum for accessing the most up-to-date and authoritative knowledge and the best practices in the field of Electrical Engineering, Technology and Information towards their sustainable development. The editors selected high quality papers from the conference that passed through a minimum of three reviewers, with an acceptance rate of 50.6 %. In the conference there were three invited papers from keynote speakers, whose papers are also included in this book, entitled: “Computational Intelligence based Regulation of the DC bus in the On-Grid Photovoltaic System”, “Virtual Prototyping of a Compliant Spindle for Robotic Deburring” and “A Concept of Multi Rough Sets Defined on Multi-Contextual Information Systems”. The conference also classified the technology innovation topics into five parts: “Technology Innovation in Robotics, Image Recognition and Computational Intelligence Applications”, “Technology Innovation in Electrical Engineering, Electric Vehicle and Energy Management”, “Technology Innovation in Electronic, Manufacturing, Instrumentation and Material Engineering”, “Technology Innovation in Internet of Things and Its Applications” and “Technology Innovation in Information, Modeling and Mobile Applications”

    Georgia Aquarium Design Space Analysis and Optimization

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    AbstractThe Ocean Voyager exhibit residing at the Georgia Aquarium Inc. (GAI) is one of the largest reef gallon aquariums in the world, with a capacity greater than 6.2M gallons. Reef aquariums are closed systems and must compensate by ‘turning over’ their complete volume of water many times a day through biological, chemical, and mechanical filtration. Due to the Georgia Aquarium being a non-profit organization, GAI sought to investigate ways to maximize efficiency and lower operating costs. This paper will focus on using low-cost software solutions to perform trade space analyses and optimization directed towards the Ocean Voyager exhibit and related GA Aquarium life support and energy systems.The software solution herein demonstrates a top-down System of Systems (SoS) to subsystem modeling approach that provides decision makers with interdisciplinary dashboard-level tools to visualize system design. The goal of the analysis is to provide executive level decision-making support for designing or enhancing existing complex systems and SoS. The analysis was performed as a capstone project by Georgia Tech graduate students progressing from cradle to finish in just 9 weeks to show the benefits of systems engineering to Georgia Aquarium staff. Integrating software SE tools into a single, aggregate model enables project engineers and decision makers to direct design directions with confidence

    Dynamic simulation of reeving systems with the extension of the modal approach in the axial direction

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    Proceedings of the ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. Volume 9: 17th International Conference on Multibody Systems, Nonlinear Dynamics, and Control (MSNDC). Virtual, Online. August 17–19, 2021. V009T09A015. ASME.In this work, the simulation of reeving systems has been studied by including axial modes using the Arbitrary Lagrangian-Eulerian (ALE) description. The reeving system is considered as a deformable multibody system in which the rigid bodies are connected by the elastic wire ropes through sheaves and reels. A set of absolute nodal coordinates and modal coordinates is employed to describe the motion and deformation in the axial direction. This new method allows the analysis of elements with non-constant axial strain along its length. In addition, modal coordinates are employed to describe the dynamic motion in the transverse direction. The non-constant axial displacement within the wire rope is computed in terms of the absolute position coordinates, longitudinal material coordinates, and modal deformation coordinates. To derive the governing equations of motion, Lagrange's equation is employed. The formulation is validated for a simple pendulum-like motion actuated by an initial velocity. The simulation results are provided to trace the movements of the payload. It can be seen that by adding modal coordinates, the axial force within the element changes. Moreover, the effects of modal coordinates in the axial direction are presented for a different number of nodes, and the resulting axial forces are compared with reference solution.Unión Europea - Horizon 2020 Marie Skłodowska-Curie project No. 860124 (THREAD

    Computational Determination of Air Valves Capacity Using CFD Techniques

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    [EN] The analysis of transient flow is necessary to design adequate protection systems that support the oscillations of pressure produced in the operation of motor elements and regulation. Air valves are generally used in pressurized water pipes to manage the air inside them. Under certain circumstances, they can be used as an indirect control mechanism of the hydraulic transient. Unfortunately, one of the major limitations is the reliability of information provided by manufacturers and vendors, which is why experimental trials are usually used to characterize such devices. The realization of these tests is not simple since they require an enormous volume of previously stored air to be used in such experiments. Additionally, the costs are expensive. Consequently, it is necessary to develop models that represent the behaviour of these devices. Although computational fluid dynamics (CFD) techniques cannot completely replace measurements, the amount of experimentation and the overall cost can be reduced significantly. This work approaches the characterization of air valves using CFD techniques, including some experimental tests to calibrate and validate the results. A mesh convergence analysis was made. The results show how the CFD models are an efficient alternative to represent the behavior of air valves during the entry and exit of air to the system, implying a better knowledge of the system to improve it.This research was funded by the Program Fondecyt Regular, grant number 1180660.García-Todolí, S.; Iglesias Rey, PL.; Mora Melia, D.; Martínez-Solano, FJ.; Fuertes-Miquel, VS. (2018). Computational Determination of Air Valves Capacity Using CFD Techniques. Water. 10(10):1-16. https://doi.org/10.3390/w10101433S1161010Liou, C. P., & Hunt, W. A. (1996). Filling of Pipelines with Undulating Elevation Profiles. Journal of Hydraulic Engineering, 122(10), 534-539. doi:10.1061/(asce)0733-9429(1996)122:10(534)Zhou, F., Hicks, F. E., & Steffler, P. M. (2002). Transient Flow in a Rapidly Filling Horizontal Pipe Containing Trapped Air. Journal of Hydraulic Engineering, 128(6), 625-634. doi:10.1061/(asce)0733-9429(2002)128:6(625)Laanearu, J., Annus, I., Koppel, T., Bergant, A., Vučković, S., Hou, Q., … van’t Westende, J. M. C. (2012). Emptying of Large-Scale Pipeline by Pressurized Air. Journal of Hydraulic Engineering, 138(12), 1090-1100. doi:10.1061/(asce)hy.1943-7900.0000631Apollonio, C., Balacco, G., Fontana, N., Giugni, M., Marini, G., & Piccinni, A. (2016). Hydraulic Transients Caused by Air Expulsion During Rapid Filling of Undulating Pipelines. Water, 8(1), 25. doi:10.3390/w8010025Zhou, F., Hicks, F. E., & Steffler, P. M. (2002). Observations of Air–Water Interaction in a Rapidly Filling Horizontal Pipe. Journal of Hydraulic Engineering, 128(6), 635-639. doi:10.1061/(asce)0733-9429(2002)128:6(635)Vasconcelos, J. G., Wright, S. J., & Roe, P. L. (2006). Improved Simulation of Flow Regime Transition in Sewers: Two-Component Pressure Approach. Journal of Hydraulic Engineering, 132(6), 553-562. doi:10.1061/(asce)0733-9429(2006)132:6(553)Li, J., & McCorquodale, A. (1999). Modeling Mixed Flow in Storm Sewers. Journal of Hydraulic Engineering, 125(11), 1170-1180. doi:10.1061/(asce)0733-9429(1999)125:11(1170)Ramezani, L., Karney, B., & Malekpour, A. (2015). The Challenge of Air Valves: A Selective Critical Literature Review. Journal of Water Resources Planning and Management, 141(10), 04015017. doi:10.1061/(asce)wr.1943-5452.0000530Stephenson, D. (1997). Effects of Air Valves and Pipework on Water Hammer Pressures. Journal of Transportation Engineering, 123(2), 101-106. doi:10.1061/(asce)0733-947x(1997)123:2(101)Bianchi, A., Mambretti, S., & Pianta, P. (2007). Practical Formulas for the Dimensioning of Air Valves. Journal of Hydraulic Engineering, 133(10), 1177-1180. doi:10.1061/(asce)0733-9429(2007)133:10(1177)De Martino, G., Fontana, N., & Giugni, M. (2008). Transient Flow Caused by Air Expulsion through an Orifice. Journal of Hydraulic Engineering, 134(9), 1395-1399. doi:10.1061/(asce)0733-9429(2008)134:9(1395)Bhosekar, V. V., Jothiprakash, V., & Deolalikar, P. B. (2012). Orifice Spillway Aerator: Hydraulic Design. Journal of Hydraulic Engineering, 138(6), 563-572. doi:10.1061/(asce)hy.1943-7900.0000548Iglesias-Rey, P. L., Fuertes-Miquel, V. S., García-Mares, F. J., & Martínez-Solano, J. J. (2014). Comparative Study of Intake and Exhaust Air Flows of Different Commercial Air Valves. Procedia Engineering, 89, 1412-1419. doi:10.1016/j.proeng.2014.11.467Martins, N. M. C., Soares, A. K., Ramos, H. M., & Covas, D. I. C. (2016). CFD modeling of transient flow in pressurized pipes. Computers & Fluids, 126, 129-140. doi:10.1016/j.compfluid.2015.12.002Zhou, L., Liu, D., & Ou, C. (2011). Simulation of Flow Transients in a Water Filling Pipe Containing Entrapped Air Pocket with VOF Model. Engineering Applications of Computational Fluid Mechanics, 5(1), 127-140. doi:10.1080/19942060.2011.11015357Davis, J. A., & Stewart, M. (2002). Predicting Globe Control Valve Performance—Part I: CFD Modeling. Journal of Fluids Engineering, 124(3), 772-777. doi:10.1115/1.1490108Stephens, D., Johnson, M. C., & Sharp, Z. B. (2012). Design Considerations for Fixed-Cone Valve with Baffled Hood. Journal of Hydraulic Engineering, 138(2), 204-209. doi:10.1061/(asce)hy.1943-7900.0000496Romero-Gomez, P., Ho, C. K., & Choi, C. Y. (2008). Mixing at Cross Junctions in Water Distribution Systems. I: Numerical Study. Journal of Water Resources Planning and Management, 134(3), 285-294. doi:10.1061/(asce)0733-9496(2008)134:3(285)Austin, R. G., Waanders, B. van B., McKenna, S., & Choi, C. Y. (2008). Mixing at Cross Junctions in Water Distribution Systems. II: Experimental Study. Journal of Water Resources Planning and Management, 134(3), 295-302. doi:10.1061/(asce)0733-9496(2008)134:3(295)Ho, C. K. (2008). Solute Mixing Models for Water-Distribution Pipe Networks. Journal of Hydraulic Engineering, 134(9), 1236-1244. doi:10.1061/(asce)0733-9429(2008)134:9(1236)Huang, J., Weber, L. J., & Lai, Y. G. (2002). Three-Dimensional Numerical Study of Flows in Open-Channel Junctions. Journal of Hydraulic Engineering, 128(3), 268-280. doi:10.1061/(asce)0733-9429(2002)128:3(268)Weber, L. J., Schumate, E. D., & Mawer, N. (2001). Experiments on Flow at a 90° Open-Channel Junction. Journal of Hydraulic Engineering, 127(5), 340-350. doi:10.1061/(asce)0733-9429(2001)127:5(340)Chanel, P. G., & Doering, J. C. (2008). Assessment of spillway modeling using computational fluid dynamics. Canadian Journal of Civil Engineering, 35(12), 1481-1485. doi:10.1139/l08-094Li, S., Cain, S., Wosnik, M., Miller, C., Kocahan, H., & Wyckoff, R. (2011). Numerical Modeling of Probable Maximum Flood Flowing through a System of Spillways. Journal of Hydraulic Engineering, 137(1), 66-74. doi:10.1061/(asce)hy.1943-7900.0000279Castillo, L., García, J., & Carrillo, J. (2017). Influence of Rack Slope and Approaching Conditions in Bottom Intake Systems. Water, 9(1), 65. doi:10.3390/w9010065Regueiro-Picallo, M., Naves, J., Anta, J., Puertas, J., & Suárez, J. (2016). Experimental and Numerical Analysis of Egg-Shaped Sewer Pipes Flow Performance. Water, 8(12), 587. doi:10.3390/w812058

    Coupling a superconducting quantum circuit to a phononic crystal defect cavity

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    Connecting nanoscale mechanical resonators to microwave quantum circuits opens new avenues for storing, processing, and transmitting quantum information. In this work, we couple a phononic crystal cavity to a tunable superconducting quantum circuit. By fabricating a one-dimensional periodic pattern in a thin film of lithium niobate and introducing a defect in this artificial lattice, we localize a 6 gigahertz acoustic resonance to a wavelength-scale volume of less than one cubic micron. The strong piezoelectricity of lithium niobate efficiently couples the localized vibrations to the electric field of a widely tunable high-impedance Josephson junction array resonator. We measure a direct phonon-photon coupling rate g/2π≈1.6 MHzg/2\pi \approx 1.6 \, \mathrm{MHz} and a mechanical quality factor Qm≈3×104Q_\mathrm{m} \approx 3 \times 10^4 leading to a cooperativity C∼4C\sim 4 when the two modes are tuned into resonance. Our work has direct application to engineering hybrid quantum systems for microwave-to-optical conversion as well as emerging architectures for quantum information processing.Comment: 9 pages, 7 figure

    Evaluation of modified nonlinear dynamic and static analyses for seismic behavior of steel moment-resisting frames

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    With the progresses made in the field of structural and earthquake engineering and with more exact knowledge gained on seismic behavior of structures, earthquake engineering and various structures have advanced a great deal and various types of analytical methods have been developed for the assessment of structures. Dynamic analysis methods are aimed at determining the accurate behavior of structures and static analysis approaches are employed to predict structural behavior for engineering purposes. Most of nonlinear dynamic techniques are time-consuming and require a large volume of computations; moreover, performing these analyses and interpreting the obtained results need special skill and expertise. Conversely, although numerous approximations and simplifications in the nonlinear static approaches have extended and promoted their applications, they have reduced the accuracy of the results obtained by these methods. For evaluation of the seismic performance of structures, the precision and speed of the process of different analytical methods are the most important factors. This has led to the development of many novel methods based on the modern nonlinear static and dynamic analyses concepts. In this research, the results of two new different methods (modal incremental dynamic and incremental modified pushover analysis) for two 3-story and 9-story steel moment-resisting frames, as typical low and mid-rise steel lateral load-carrying systems, have been evaluated and compared with the results of the exact nonlinear incremental dynamic analysis. Based on the findings of this research, for the studied frames, the application of both analytical methods for low-rise frames gives appropriate results for all seismic records at different intensity levels; while for the mid-rise frames, the accuracy of the static analysis method has decreased; although a proper safety margin exists for this approach and also the sensitivity of the static method is less than that of the dynamic method

    Supply chain network considerations for e-retail of luxury goods in Canada

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    Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 85-89).The Internet has changed the way people purchase goods in the 21st century: many types of goods and services have become available online. Luxury goods followed this trend after an initial delay, primarily due to the nature of these goods. At the time of the preparation of this document, there were no proven guidelines for building the most successful e-retail website for luxury goods from the brand management and profitability perspectives. Ralph Lauren (RL) is an established American brand, well known for quality and consistent style in the following categories: clothing for women, men, and children; home goods, accessories; and fragrances. RL Corporation houses many labels that constitute premium and luxury offerings. RL currently sells through the Internet in many countries, in addition to countless company owned stores, 9 flagship stores, department stores and boutiques distributed around the world. To continue growth, RL wants to launch an e-retail website for Canada. This thesis aims to provide supply chain network considerations for the successful operation of the Canadian e-retail website for RL. These considerations stem from a careful look into potential luxury website characteristics that would meet the company objective of elevating the brand towards the luxury category. It is recommended that RL secure expansion capacity that will likely be necessary for B2C operation at its Toronto distribution center (DC). In addition, material handling equipment that will process a high volume of small orders should be placed in this DC. The Vancouver cross-docking facility could be expanded in the future as prompted by sales volume and coupled with a DC to cater to the West Coast of Canada. Also, it is recommended that advanced customer tracking systems and databases be employed, especially to determine high value customers for tailored offerings in the luxury segment.by Dilek Tansoy and Yi Linn Teo.M.Eng.in Logistic
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