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Reno, NV, United States

Nassiri S.,Flow Modeling and Simulation
Chinese Physics Letters | Year: 2014

Using instanton effects, we consider a U(3)C × U(3)L × U(3)R gauge symmetry obtained from intersecting D6-branes. This is equivalent to the trinification model extended by the three U(1) factors that survive as global symmetries in the low energy effective model. In the corresponding three-stack, the fermion masses are induced by the possible stringy corrections to the corresponding superpotential by using E2-instantons. Using the known data with neutrino masses mvτ ∼ 1 eV, we show the magnitudes of the relevant scales. © 2014 Chinese Physical Society and IOP Publishing Ltd. Source


Ebrahimi H.B.,Flow Modeling and Simulation | Malo-Molina F.J.,Air Force Research Lab | Gaitonde D.V.,Ohio State University
Journal of Propulsion and Power | Year: 2012

High-fidelity simulations with a validated methodology are employed to explore the physical processes associated with different injection strategies on supersonic combustion. The configurations consider a commonly employed open single-cavityflameholder. The effects ofdifferent injector locations and injection angles are examined under the constraint that the total fuel mass flow rate is the same. The numerical approach solves the full three-dimensional Navier-Stokes equations, supplemented with a two-equation k-ω turbulence closure. The specific injection locations include 10 different arrangements that examine fuel injection upstream of the cavity, on the backward step, on the cavity bottom wall, and on the downstream ramp. The angles of the fuel port injection slots include combinations of parallel and 27 and 90 deg to the airflow inside the cavity. One case with a closed cavity is also examined for comparison. The simulations are employedto characterize the performance with qualitative and quantitative mixing metrics. Detailed analysis of the results reveals both expected and unexpected findings. As anticipated, the closed cavity performs poorly relative to its open counterpart. However, an injection strategy that enhances the natural circulation pattern of the cavity is found to besuperior to one that opposes it. Another counterintuitive finding is that although direct injection of the fuel upstream of the cavity into the main stream results in deeper penetration, the fuel from different injectors remains distinct, with relatively small spanwise mixing. On the other hand, injection on the floor of the cavity results in more diffused fuel distribution. Copyright © 2012 by the American Institute of Aeronautics and Astronautics, Inc. Source


Ennadifi S.E.,Flow Modeling and Simulation
Physics of Particles and Nuclei Letters | Year: 2015

We investigate the Yukawa couplings sector in the minimal gauge theory U(3) × U(2) × U(1) with the Standard Model chiral and Higgs spectrum based on three stacks of intersecting D-branes. In this model, stringy corrections are required to induce the missing Yukawa couplings and generate hierarchical pattern. Under the known data, we assign the realistic Yukawa texture and then bound their strengths. © 2015, Pleiades Publishing, Ltd. Source


Occurrence of a venous thromboembolism (VTE) in patients undergoing major orthopedic surgery who are not given thromboprophylactic therapy presents considerable danger to patient medical outcomes and a significant economic burden to the health care system at large. Apixaban is a direct factor Xa inhibitor that has been shown in clinical trial use to safely reduce the composite of VTE and mortality rates in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA); however, the cost-effectiveness of apixaban treatment in Canadian settings has not been studied. Our study evaluated the cost-effectiveness of apixaban compared with enoxaparin as VTE preventive therapy in patients undergoing elective THA or TKA in Canada. An economic model, including both a decision-tree component and a Markov model, was created. The decision tree considered VTE, bleeding, and mortality incidence that occurred in patients within 90 days post-surgery using data from the Apixaban Versus Enoxaparin for Thromboprophylaxis After Knee or Hip Replacement (ADVANCE) trials, which compared apixaban therapy with 30-mg twice daily and 40-mg daily enoxaparin treatment. The Markov model provided the option to simulate events that may occur over the long term, such as recurrent VTE and post-thrombotic syndrome. Outcomes during the short-term phase directly impact the risk of events occurring during the long-term phase (5 years post-surgery). The results of our analysis indicated that apixaban is dominant (ie, more effective and less expensive) than enoxaparin in treating patients undergoing THA and TKA. There were fewer occurrences of VTEs, bleeding events, recurrent VTEs, and post-thrombotic syndrome events in the TKA population with apixaban therapy. Similar results were seen in patients undergoing THA, with the exception of bleeding events, which were more common with apixaban treatment. Savings of $180 to $270 per patient are expected with apixaban treatment compared with enoxaparin treatment, and health outcomes in general are better with apixaban use. Sensitivity analyses yielded consistent results across the THA and TKA populations. : This is the first economic evaluation of apixaban use for VTE thromboprophylaxis in the Canadian setting, and our study results show apixaban to be a cost-effective treatment alternative to preventive treatment with enoxaparin. Source


Grant
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 149.96K | Year: 2011

ABSTRACT: Flow Modeling and Simulation proposes to develop a code designated Scramjet Simulation Tool (SCRAMSIM) to provide a powerful multi-level tool suitable for tight integration into the design, test and evolution cycle. The code will be based on the HEAT3D code. SCRAMSIM will be designed to reduce risks and costs, compress schedules (short term) and enhance physics insight (long term) by encompassing quick turnaround simple models as well as large scale simulations for detailed first-principles analysis. BENEFIT: A key goal of the SBIR effort is to establish and enhance the commercial position of our software, including SCRAMSIM and HEAT3D. Our business model is to provide the software and support to our customers, and then guide them in executing the software for whatever problem is of interest.

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