53 research outputs found
Inter-operator resource sharing in 4G LTE cellular networks
No full textThe dramatic increase in wireless data traffic challenges cellular network operators to increase wireless access and system capacity, and to reduce costs of deploying and operating the network infrastructure. In light of the cost and complexity of large scale networks as well as the absence of new spectrum, the paradigm of resource sharing is explored to address these challenges. In this research, we examine three cellular resource sharing approaches: Capacity, Spectrum and Infrastructure Hardware and propose various sharing options in the context of 4G LTE. We propose a unified coordinated sharing process and architecture by introducing a new network Sharing Entity (SE). The SE enables dynamic creation, modification and termination of resource sharing agreements among operator that can be conditional or restrictive in time, space and other dimensions. We present the required technologies in two cases: (1) Traditional infrastructure for capacity and spectrum sharing options wherein the networks of operators participating in sharing are physically independent infrastructures. (2) Virtualized infrastructure for hardware sharing option wherein a single physical infrastructure virtualizes infrastructures of participating operators. We model two geographically overlapped LTE cellular networks, operated by two operators, with the proposed sharing architecture and process. We evaluate sharing options based on multiple performance metrics and cost saving estimates under light, moderate and heavy loading scenarios via simulations in collocated and non-collected deployment topologies.Ph. D.Includes bibliographical referencesIncludes vitaby Jignesh S. Pancha
Correction: Panchal et al. 3D FEM Simulation and Analysis of Fractal Electrode-Based FBAR Resonator for Tetrachloroethene (PCE) Gas Detection. Fractal Fract. 2022, 6, 491
No full textAvanish Bhadauria from the Council of Scientific and Industrial Research–Central Electronics Engineering Research Institute (CSIR–CEERI), India, was not included as an author in the original publication [...
Erratum
No full text Smith MV, Panchal HB, Ruberte Thiele RA, Sekiya JK. Effect of acetabular labrum tears on hip stability and labral strain in a joint compression model. Am J Sports Med. 2011;39(suppl 1):103S-110S. (Original 10.1177/0363546511400981) In the above article, credentials for one of the authors were not listed. There should be an “MS” degree following author Ramon A. Ruberte Thiele's name on the author line. The updated author line should read as follows: Matthew V. Smith, MD, Hemang B. Panchal, MBBS, MPH, Ramon A. Ruberte Thiele, MS, and Jon K. Sekiya, MD In addition, it should be noted that this paper received the 2010 Excellence in Research Award; as such, it was presented at the 36th annual meeting of the AOSSM, Providence, Rhode Island, July 2010. </jats:p
A new test setup for studying sand behaviour inside an immersed tunnel joint gap
No full textDuring inspections of several immersed tunnels in the Netherlands, damage of immersion joints has been observed. In some cases the Gina seal has moved inwards from its original location, and in other cases a permanent elongation of the entire tunnel structure has been measured. For both cases it has been hypothesised that a seasonal expansion and contraction of the tunnel elements allows sand to enter the joint gap between elements during winter, where it is compacted during summer, leading to an increasing amount of sand in the joint gap over the years. In order to study this mechanism and assess its impact, a 1:3 scale model joint gap has been designed and constructed. This setup can simulate expansion and contraction cycles of the joint and measure stresses in the joint gap and deformations of the Gina seal. First test results are presented here and show that compaction of the sand entering the joint gap indeed occurs and leads to the observed large inwardsdeformations of the Gina seals.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Concrete StructuresGeo-engineerin
Ultra-thin friction stir welding on Aluminum alloy
No full textUltra-thin sheets' welding is an intricate process either by conventional or advanced techniques. In the present investigation, Micro friction stir welding (FSW) was successfully performed to join the ultra-thin (0.5 mm thick) commercial aluminum. Suitable fixture and tool were developed for the ultra-thin sheets to perform experiments. Velocity ratio of rotational speed to transvers speed was varied to obtain ultra-thin friction stir welding. The welded samples were investigated by visual examination, macro-graphs, microstructure, tensile testing with fracture surface analysis and micro hardness distribution. The results revealed that, the sound joint was achieved at the velocity ratio of 13.71. The tensile strength of 100.877 N/mm2 and elongation of 23.12% were obtained, which were 90.77% and 51.377% of the parent material respectively. Fracture surfaces after tensile testing was observed with elongated dimples indicating ductile fracture. The maximum micro hardness of 94 HV was observed in the weld zone
The mental effects of COVID on service industry workers
No full textThere are increasing numbers of mental issues because of COVID. Research shows that mental health problems (Stewart, 2020; Panchal, et. al., 2021) and instances of substance abuse (American Addiction Center, 2021; Murray, 2021) are highest for those who work in restaurants and service industries. This literature review highlights the struggle, fears, and anxiety associated with COVID and provides ways for service workers to cope with the struggles of our new way of life (Evans, 2021)
High pressure phase transitions in NdVO4
No full textCopyright (2015) American Institute of Physics. This article may
be downloaded for personal use only. Any other use requires prior
permission of the author and the American Institute of Physics.Raman-scattering measurements on NdVO4
suggest a pressure-induced zircon to monazite phase transition beyond 5.9
GPa. The monazite phase undergoes a second phase transition to a yet unknown phase at 18.1 GPa. Lattice-dynamics calculations
well support the experimental findings and predict a possible orthorhombic structure for the post-monazite structure of NdVO4.Panchal, V.; Errandonea, D.; Manjón Herrera, FJ.; Muñoz, A.; Rodríguez Hernández, P.; Bettinelli, M.; Achary, S.... (2015). High pressure phase transitions in NdVO4. AIP Conference Proceedings. 1665:030006-1-030006-3. doi:10.1063/1.4917581S030006-1030006-3166
A Quasi-Feed-In-Tariff policy formulation in micro-grids: A bi-level multi-period approach
No full textA Quasi-Feed-In-Tariff (QFIT) policy formulation is presented for micro-grids that integrates renewable energy generation considering Policy Makers' and Generation Companies' (GENCOs) objectives assuming a bi-level multi-period formulation that integrates physical characteristics of the power-grid. The upper-level problem corresponds to the PM, whereas the lower-level decisions are made by GENCOs. We consider that some GENCOs are green energy producers, while others are black energy producers. Policy makers incentivize green energy producers to generate energy through the payment of optimal time-varying subsidy price. The policy maker's main objective is to maximize an overall social welfare that includes factors such as demand surplus, energy cost, renewable energy subsidy price, and environmental standards. The lower-level problem corresponding to the GENCOs is based on maximizing the players' profits. The proposed QFIT policy differs from the FIT policy in the sense that the subsidy price-based contracts offered to green energy producers dynamically change over time, depending on the physical properties of the grid, demand, and energy price fluctuations. The integrated problem solves for time-varying subsidy price and equilibrium energy quantities that optimize the system welfare under different grid and system conditions. © 2014 Elsevier Ltd.Benedict E., 1992, TECHNICAL REPORT; Christie RD, 2000, P IEEE, V88, P170, DOI 10.1109-5.823997; Couture T., 2009, NRELTP6A245551; Couture T., 2010, NRELTP6A244849; Duan B., 2010, 2010 3 IEEE INT C CO, V9, P188; Ferris M.C., 1997, P APPL MATH SERIES S; Gabriel S. A., 2012, COMPLEMENTARITY MODE; Gan L., 2013, DEC CONTR CDC 2013 I, P5614; Han LS, 2013, OPER RES LETT, V41, P92, DOI 10.1016-j.orl.2012.11.006; Hawthorne B. D., 2012, ASME INT DES ENG TEC; Hobbs BF, 2001, IEEE T POWER SYST, V16, P194, DOI 10.1109-59.918286; Huang D., 2011, THESIS DELFT U TECHN; Kirschen D. S., 2004, FUNDAMENTALS POWER S; Masters G. M., 2004, RENEWABLE EFFICIENT; Murty K.G., 1997, SIGMA SERIES APPL MA; National Grid, 2013, 2013 STAND EL SERV L; Newbery DM, 1998, RAND J ECON, V29, P726, DOI 10.2307-2556091; Osborne M. J., 1994, COURSE GAME THEORY; Pieper H., 2001, THESIS STANFORD U; PJM, 2010, TECHNICAL REPORT; Poputoaia D., 2008, EUROPEAN EXPERIENCE; Roozbehani M., 2011, 50 IEEE C DEC CONTR; Sumbera J., 2011, TECHNICAL REPORT; Taha A.F., 2013, BUILD RES COLL EL SY; Taha A.F., 2013, IEEE T SYSTEMS MAN C; Tamas MM, 2010, ENERG POLICY, V38, P4040, DOI 10.1016-j.enpol.2010.03.028; Weisenmiller R., 2012, CEC3002012002CMF0
Educating Anti-Vaccination Communities at Risk
No full textThe Reluctance to Vaccinate Could be Mitigated by Eliminating Philosophical Exemptions and Identifying Causal Factors for AutismSpring 2015Accompanied by video fil
Effect of non-homogeneity on orthotropic creep stresses in a pressurized circular cylinder
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