Chicago's economic transformation from 1970 to 2000

Chicago (Ill.) ; Manufactures ; Service industries

Impacts of Brownian Motion, Thermophoresis and Ohmic Heating on Chemically Reactive Pulsatile MHD Flow of Couple Stress Nanofluid in a Channel

354-366In this study, the magnetohydrodynamic pulsatile flow of a couple stress nanofluid in a channel has been discussed in detail by adopting Buongiorno’s nanofluid model. The impacts of Brownian motion, thermophoresis, Ohmic heating, viscous dissipation and chemical reaction on heat, and mass transfer of blood based nanofluid are considered. The current concept is significant in the field of nano-drug supply, dynamics of physiological fluids, and biomedicines. The governing partial differential equations are converted into a set of ODEs (ordinary differential equations) by employing a perturbation scheme. The resulting non-dimensional system is numerically interpreted to determine the impact of various emerging parameters on flow variables by utilizing the shooting technique with the support of the Runge-Kutta procedure. The outcomes reveal that the temperature rises with the magnifying viscous dissipation, Brownian motion, and thermophoresis parameters, whereas the opposite trend can be seen with an escalation in the couple stress parameter. Heat transfer rate is an accelerating function of Brownian motion and thermophoresis parameters while it is a decelerating function of couple stress parameter and Hartmann number. Mass transfer rate declines with increasing values of thermophoresis parameter and Lewis number

Shear Resistance of portal Frame Reinforced with Bamboo and Steel Rebar: Experimental and Numerical Evaluation

The main objective of this study is to evaluate the shear resistance of portal frame fabricated with bamboo and steel rebar by following experimental and numerical approaches. In support of sustainable construction, bamboo stripes were utilized as a partial replacement of steel rebar at tension zone of members that are subjected to lateral loading. The performance of nominal portal frame, which are fabricated with steel reinforcement was compared to the portal frames having several replacements of steel reinforcement with bamboo, in terms of seismic resistance and lateral load capacity. The experimental data was correlated based on software analysis using ABAQUS. The partial replacement of steel with bamboo under tension zone of the beams in portal frame was found to be highly effective, and also that the flexural rigidity of the partial bamboo reinforced frame was slightly higher than the nominal portal frame. This study provides insight on the possibility of reinforcing structural members with bamboo, when lateral loading is imminent on the structure

Search for Eccentric Black Hole Coalescences during the Third Observing Run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass $M>70$ $M_\odot$) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities $0 < e \leq 0.3$ at $0.33$ Gpc$^{-3}$ yr$^{-1}$ at 90\% confidence level.Comment: 24 pages, 5 figure

Saga of Saras: Part - II: Report of Significant Events/Milestones reached during the making of SARAS Prototype - II and the lessons we learnt from PT - 1

This NAL Project Document highlights the pioneering efforts made by the centre for Civil Aircraft Design and Development in building the SARAS prototype-II. SARAS prototype-II, NAL's 14-seater light transport aircraft had its successful maiden flight on 18 April 2007 at 09:05 a.m. Several improvements have been incorporated in SARAS PT-II compared to the first prototype. Most important among these are the incorporation of higher power engines, Pamp;WC 6A-67A of 1200 hp each and new propellers of larger diameter. The supporting stubwing structure and the engine nacelle have also been modified to suite the new engines. Added to this, significant improvements have been incorporated in the layout of flight control system, avionics and electrical systems. These improvements have brought PT-II much closer to the final production standard aircraft

STUDIES ON THE STRESS FLUCTUATIONS IN SHEARED STOKESIAN SUSPENSIONS USING CHAOS THEORY AND NONLINEAR DYNAMICS

The thesis report results obtained from a detailed analysis of the fluctuations of the rheological parameters viz. shear and normal stresses, simulated by means of the Stokesian Dynamics method, of a macroscopically homogeneous sheared suspension of neutrally buoyant non-Brownian suspension of identical spheres in the Couette gap between two parallel walls in the limit of vanishingly small Reynolds numbers using the tools of non-linear dynamics and chaos theory for a range of particle concentration and Couette gaps. The thesis used the tools of nonlinear dynamics and chaos theory viz. average mutual information, space-time separation plots, visual recurrence analysis, principal component analysis, false nearest-neighbor technique, correlation integrals, computation of Lyapunov exponents for a range of area fraction of particles and for different Couette gaps. The thesis observed that one stress component can be predicted using another stress component at the same area fraction. This implies a type of synchronization of one stress component with another stress component. This finding suggests us to further analysis of the synchronization of stress components with another stress component at the same or different area fraction of particles. The different model equations of stress components for different area fraction of particles hints at the possible existence a general formula for stress fluctuations with area fraction of particle as a paramete