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Karachi, Pakistan

The NED University of Engineering and Technology, is a public research university located in the urban area of Karachi, Sindh, Pakistan. It is one of the oldest institution of higher learning in Pakistan and is noted for its strong emphasis on higher learning in science and technology.Founded in 1922 as a technical project to provide training to civil engineers working in building the Sukkur Barrage, the university came to its modern form after being established by the British government. The university is named for its benefactor, donor, and philanthropist, Nadirshaw Eduljee Dinshaw by the government. Besides its focus on science and engineering programmes, the university also offers wide range of academic programmes in philosophy, humanities, and fine arts for undergraduate, post-graduate, and doctoral studies. The university is also a member of Association of Commonwealth Universities of the United Kingdom.Primarily, its financial endowment and the scientific research is directed towards the development of the engineering, management, natural, and medical science. Organized into six science faculties as well as various associated research institutions affiliated with the university in Karachi. Wikipedia.

Friston K.J.,University College London | Kahan J.,University College London | Razi A.,University College London | Razi A.,NED University of Engineering and Technology | And 2 more authors.

This paper examines intrinsic brain networks in light of recent developments in the characterisation of resting state fMRI timeseries - and simulations of neuronal fluctuations based upon the connectome. Its particular focus is on patterns or modes of distributed activity that underlie functional connectivity. We first demonstrate that the eigenmodes of functional connectivity - or covariance among regions or nodes - are the same as the eigenmodes of the underlying effective connectivity, provided we limit ourselves to symmetrical connections. This symmetry constraint is motivated by appealing to proximity graphs based upon multidimensional scaling. Crucially, the principal modes of functional connectivity correspond to the dynamically unstable modes of effective connectivity that decay slowly and show long term memory. Technically, these modes have small negative Lyapunov exponents that approach zero from below. Interestingly, the superposition of modes - whose exponents are sampled from a power law distribution - produces classical 1/. f (scale free) spectra. We conjecture that the emergence of dynamical instability - that underlies intrinsic brain networks - is inevitable in any system that is separated from external states by a Markov blanket. This conjecture appeals to a free energy formulation of nonequilibrium steady-state dynamics. The common theme that emerges from these theoretical considerations is that endogenous fluctuations are dominated by a small number of dynamically unstable modes. We use this as the basis of a dynamic causal model (DCM) of resting state fluctuations - as measured in terms of their complex cross spectra. In this model, effective connectivity is parameterised in terms of eigenmodes and their Lyapunov exponents - that can also be interpreted as locations in a multidimensional scaling space. Model inversion provides not only estimates of edges or connectivity but also the topography and dimensionality of the underlying scaling space. Here, we focus on conceptual issues with simulated fMRI data and provide an illustrative application using an empirical multi-region timeseries. © 2014. Source

Rafi M.M.,NED University of Engineering and Technology | Nadjai A.,University of Ulsters Fire Facility
ACI Materials Journal

Fiber-reinforced polymer (FRP) bars are made of innovative materials and the establishment of the fire resistance of FRP reinforced concrete (RC) is necessary for their widespread application. Experimental behaviors of carbon FRP (CFRP) and hybrid (steelCFRP) bar RC beams at elevated temperatures were investigated in this study. Data are presented from fire tests of six simply supported beams that were fabricated using normalweight concrete. The effect of varying concrete cover and reinforcing bar arrangement was studied. The beams were tested in a floor furnace and carried a service load of 40% of their ambient temperature load capacity. Nonlinear temperature distribution across the cross section was found. This caused additional beam curvature and stress that is known as eigen-stress. At temperatures beyond the glass transition temperature of the polymer resin, the FRP bars debondedfrom the concrete and behaved as tie rods if anchored at the ends. Consequently, the FRP RC beam resists thermomechanical loads by arch action. On the other hand, the thermal behaviors of hybrid beams were a combination of arch and beam action. Failure of a beam was typically initiated by reinforcing bar slip due to anchorage failure. All six beams failed in flexure, which was also the intended failure mode at ambient temperature. Hybrid bar reinforced beams were more ductile compared to FRP RC beams. The CFRP bar reinforced beams showed better strength and stiffness characteristics compared to the hybrid beams. Copyright © 2011, American Concrete Institute. All rights reserved,. Source

Chen Z.C.,Concordia University at Montreal | Khan M.A.,NED University of Engineering and Technology
International Journal of Advanced Manufacturing Technology

With the development of a new function of computer numerical control controllers, nonuniform rational B-spline (NURBS) interpolation, NURBS tool path generation for sculptured surface machining is under extensive research. The common procedures of the current NURBS tool path planning methods are as follows: first, to find a group of cutter contact points on a sculptured surface; second, to calculate their corresponding cutter locations (CLs); then, to fit a NURBS tool path to the CLs within a prescribed tolerance; and finally, to inspect the tool path for possible gouge by the tool and delete the invalid path segments, if any. However, the NURBS tool path has the following problems: (a) although it passes through the discrete CLs of the theoretical CL path, the deviation along the two paths could be larger than the tolerance; (b) its parameter is not the arc length of the path; and (c) it is difficult to detect gouge along the NURBS path and to remove the invalid segments from it. Consequently, NURBS tool paths generated with the current methods of commercial computer-aided design/computer-aided manufacturing (CAD/CAM) software cannot be used to make smooth and accurate surfaces. To address these problems, this work proposes a new approach to generating arc length parameterized NURBS tool paths with high accuracy in terms of the theoretical CL paths and without gouge and interference. Two practical examples in this work clearly demonstrate the feasibility of this approach and the advantages of the generated NURBS tool paths. Therefore, this approach can be implemented into the CAD/CAM software to promote NURBS machining in industry. © 2013 Springer-Verlag London. Source

Zuberi M.J.S.,Middle East Technical University | Ali S.F.,NED University of Engineering and Technology
Renewable and Sustainable Energy Reviews

Landfills all around the world are one of the major sources that contribute towards global warming and climate change. Although landfilling should be prioritized last in the waste management hierarchy due to highest greenhouse gas emissions as compared to other waste management systems it is still very common around the world. In this study, methane emissions are estimated by applying First Order Decay model to landfills in Pakistan over the latest data available by Pakistan Environmental Protection Agency. Results demonstrate that nearly 14.18 Gg of methane is emitted from the landfills in Pakistan each year. By combusting this methane in the form of biogas collected from the landfills as a waste management scheme we can reduce greenhouse effect up to ∼88%. Same percentage is observed when we apply the similar analysis over the potentially improved practice. Also, Pakistan is facing severe economic crises due to continuous increasing gap between energy demand and supply. Demand is increasing exponentially while supply is observed to remain constant over the last few years due to frozen capacity in spite of having significant renewable/alternate energy resources. Current electricity shortfall has reached up to 6000 MW. Present operational landfills in Pakistan can only contribute up to ∼0.1% to cater the total deficit which does not make any significant difference but if 75% of the total waste generated today is collected and 50% of it landfilled then Pakistan has the potential to produce ∼83.17 MW of power that can contribute up to 1.4% to overcome the current power shortage. The outcomes of this paper may also be applicable to other developing countries having similar resources. © 2014 Elsevier Ltd. All rights reserved. Source

Ahmed N.,NED University of Engineering and Technology
Proceedings of the Institution of Civil Engineers: Municipal Engineer

Low-income settlements in Karachi have faced acute water shortages during the past two decades. Different approaches were devised to address this situation by concerned stakeholders comprising area residents, water utility, local government officials, community groups, and formal and informal water vendors. Development of awami community-managed tanks was one such option. Evolved through cooperative action, philanthropic contributions and partial government subsidy, the awami tanks served as an interim water supply arrangement for several years. Earlier documentation and analysis of this format of supply adequately established this factor. A recent survey of the status of some low-income localities has shown that while awami tanks are largely abandoned, the existing service is far below the desired level. This paper examines the relevance of awami tanks in the present context of water supply arrangements. Various localities in Orangi in Karachi have been studied for water supply problems. On-site observations, focused group meetings with area residents and interviews with key respondents were the main components of fact-finding work. © ICE Publishing: All rights reserved. Source

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