82 research outputs found

    Services Trade Negotiations in the Doha Round : Opportunities and Risks for Pakistan

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    This paper seeks to examine how locking-in of Pakistans unilateral liberalization at the WTO/GATS and further liberalization of services trade would affect Pakistans competitiveness. Focusing on the opportunities and risks of such liberalization the paper discusses possible options regarding the corollary regulatory reforms and other flanking measures that may be needed to achieve these goals. The sectors studied in this paper are (a) construction and related engineering services; (b) architecture, engineering and integrated engineering services; (c) energy services; and (d) environmental services.liberalization, Services, regulation, Pakistan

    Prospects of Wheat and Sugar Trade between India and Pakistan : A Simple Welfare Analysis

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    This paper asks how opening up of wheat and sugar trade between two nuclear neighbours, India and Pakistan, would affect welfare in the two countries. We conduct a partial equilibrium analysis to simulate welfare implications of trade between the two countries under three alternative trade regimes : a) under an FTA between India and Pakistan, b) under SAFTA, and c) under a grant of mostfavoured nation (MFN) to India by Pakistan. We conduct simple welfare analysis for wheat, on the basis of real world data of FY2005, and for sugar, based on data for FY 2000-01. In both these years, India had a net surplus and Pakistan had a net deficit for both wheat and sugar. We show that among other things, favourable weather conditions play a critical role in generating these surpluses, which are most likely to get reversed in years when weather conditions become more favourable to Pakistan. While we find there would be net gains to both countries, in case trade happens, the highest welfare gains accrue to both countries under free trade agreement. Further analysis reveals that if subsidies to Indian wheat farmers are removed, their competitive edge disappears in favour of wheat farmers in Pakistan.wheat, sugar, trade, weather conditions, Pakistan, India, subsidies

    Elastic Deformation of Polycrystals

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    We propose a framework to model elastic properties of polycrystals by coupling crystal orientational degrees of freedom with elastic strains. Our model encodes crystal symmetries and takes into account explicitly the strain compatibility induced long-range interaction between grains. The coupling of crystal orientation and elastic interactions allows for the rotation of individual grains by an external load. We apply the model to simulate uniaxial tensile loading of a 2D polycrystal within linear elasticity and a system with elastic anharmonicities that describe structural phase transformations. We investigate the constitutive response of the polycrystal and compare it to that of single crystals with crystallographic orientations that form the polycrystal.Comment: 4 pages, 4 ps figure

    Viscoelastic Properties of Dynamically Asymmetric Binary Fluids Under Shear Flow

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    We study theoretically the viscoelastic properties of sheared binary fluids that have strong dynamical asymmetry between the two components. The dynamical asymmetry arises due to asymmetry between the viscoelastic stresses, particularly the bulk stress. Our calculations are based on the two-fluid model that incorporates the asymmetric stress distribution. We simulate the phase separation process under an externally imposed shear and compare the asymmetric case with the usual phase separation under a shear flow without viscoelastic effects. We also simulate the behavior of phase separated stable morphologies under applied shear and compute the stress relaxation.Comment: 10 pages text, 9 figure

    Domain Size Dependence of Piezoelectric Properties of Ferroelectrics

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    The domain size dependence of piezoelectric properties of ferroelectrics is investigated using a continuum Ginzburg-Landau model that incorporates the long-range elastic and electrostatic interactions. Microstructures with desired domain sizes are created by quenching from the paraelectric phase by biasing the initial conditions. Three different two-dimensional microstructures with different sizes of the 90o90^{o} domains are simulated. An electric field is applied along the polar as well as non-polar directions and the piezoelectric response is simulated as a function of domain size for both cases. The simulations show that the piezoelectric coefficients are enhanced by reducing the domain size, consistent with recent experimental results of Wada and Tsurumi (Brit. Ceram. Trans. {\bf 103}, 93, 2004) on domain engineered BaTiO3BaTiO_{3} Comment: submitted to Physical Review

    Microstructure from ferroelastic transitions using strain pseudospin clock models in two and three dimensions: a local mean-field analysis

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    We show how microstructure can arise in first-order ferroelastic structural transitions, in two and three spatial dimensions, through a local meanfield approximation of their pseudospin hamiltonians, that include anisotropic elastic interactions. Such transitions have symmetry-selected physical strains as their NOPN_{OP}-component order parameters, with Landau free energies that have a single zero-strain 'austenite' minimum at high temperatures, and spontaneous-strain 'martensite' minima of NVN_V structural variants at low temperatures. In a reduced description, the strains at Landau minima induce temperature-dependent, clock-like ZNV+1\mathbb{Z}_{N_V +1} hamiltonians, with NOPN_{OP}-component strain-pseudospin vectors S{\vec S} pointing to NV+1N_V + 1 discrete values (including zero). We study elastic texturing in five such first-order structural transitions through a local meanfield approximation of their pseudospin hamiltonians, that include the powerlaw interactions. As a prototype, we consider the two-variant square/rectangle transition, with a one-component, pseudospin taking NV+1=3N_V +1 =3 values of S=0,±1S= 0, \pm 1, as in a generalized Blume-Capel model. We then consider transitions with two-component (NOP=2N_{OP} = 2) pseudospins: the equilateral to centred-rectangle (NV=3N_V =3); the square to oblique polygon (NV=4N_V =4); the triangle to oblique (NV=6N_V =6) transitions; and finally the 3D cubic to tetragonal transition (NV=3 N_V =3). The local meanfield solutions in 2D and 3D yield oriented domain-walls patterns as from continuous-variable strain dynamics, showing the discrete-variable models capture the essential ferroelastic texturings. Other related hamiltonians illustrate that structural-transitions in materials science can be the source of interesting spin models in statistical mechanics.Comment: 15 pages, 9 figure

    Performance Evaluation of an Intelligent and Optimized Machine Learning Framework for Attack Detection

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    In current decades, the size and complexity of network traffic data have risen significantly, which increases the likelihood of network penetration. One of today's largest advanced security concerns is the botnet. They are the mechanisms behind several online assaults, including Distribute Denial of Service (DDoS), spams, rebate fraudulence, phishing as well as malware attacks. Several methodologies have been created over time to address these issues. Existing intrusion detection techniques have trouble in processing data from speedy networks and are unable to identify recently launched assaults. Ineffective network traffic categorization has been slowed down by repetitive and pointless characteristics. By identifying the critical attributes and removing the unimportant ones using a feature selection approach could indeed reduce the feature space dimensionality and resolve the problem.Therefore, this articledevelops aninnovative network attack recognitionmodel combining an optimization strategy with machine learning framework namely, Grey Wolf with Artificial Bee Colony optimization-based Support Vector Machine (GWABC-SVM) model. The efficient selection of attributes is accomplished using a novel Grey wolf with artificial bee colony optimization approach and finally the Botnet DDoS attack detection is accomplished through Support Vector machine.This articleconducted an experimental assessment of the machine learning approachesfor UNBS-NB 15 and KDD99 databases for Botnet DDoS attack identification. The proposed optimized machine learning (ML) based network attack detection framework is evaluated in the last phase for its effectiveness in detecting the possible threats. The main advantage of employing SVM is that it offers a wide range of possibilities for intrusion detection program development for difficult complicated situations like cloud computing. In comparison to conventional ML-based models, the suggested technique has a better detection rate of 99.62% and is less time-consuming and robust

    Effect of provision of home-based curative health services by public sector health-care providers on neonatal survival: a community-based cluster-randomised trial in rural Pakistan

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    Background Although the effectiveness of community mobilisation and promotive care delivered by community health workers in reducing perinatal and neonatal mortality is well established, evidence in support of home-based neonatal resuscitation and infection management is mixed. We assessed the effectiveness of adding training in neonatal bag and mask resuscitation and oral antibiotic therapy for suspected neonatal infections to a basic preventive and promotive interventions package delivered by public sector community-based lady health workers (LHWs) in rural Pakistan. Methods We did a cluster-randomised controlled trial in two subdistricts of Naushahro Feroze in rural Sindh, Pakistan, between April 15, 2009, and Dec 10, 2012. LHWs, trained in basic newborn resuscitation and in recognition and treatment (with oral amoxicillin) of suspected neonatal respiratory infections, were linked with traditional birth attendants and encouraged to attend home births. Control clusters received routine care through the existing national programme. The primary outcome was all-cause neonatal mortality. Independent data collection teams recorded data for all pregnancies and their outcomes, morbidity, mortality, and household practices related to maternal and newborn care. Findings Of the 27 randomised clusters with functional LHW programmes, 13 were allocated to the intervention group (n=242 749) and 14 to the control group (n=256 985). In the intervention group, LHWs did 80% of the planned community mobilisation sessions, but were able to attend only 1184 (14%) of 8425 deliveries and 4318 (25%) of 17 288 neonatal visits within 72 h of birth (p<0·0001 for both variables compared with the control group). The neonatal mortality rate was 42 deaths per 1000 livebirths in intervention clusters compared with 55 per 1000 in the control group (risk ratio 0·80, 95% CI 0·68–0·93; p=0·005). Interpretation The reduction in neonatal mortality in intervention clusters occurred against a background of improvements in domiciliary practices for maternal and newborn care. However, the poor reach of LHWs in accessing newborn infants at birth and in the early postnatal period underscores the limitations of tasking community health workers in public sector programmes working in similar circumstances with such complex interventions. Such community-based interventions in health systems should be accompanied by concerted efforts to improve quality of care in facilities and referral systems

    Bogomol'nyi Decomposition for Vesicles of Arbitrary Genus

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    We apply the Bogomol'nyi technique, which is usually invoked in the study of solitons or models with topological invariants, to the case of elastic energy of vesicles. We show that spontaneous bending contribution caused by any deformation from metastable bending shapes falls in two distinct topological sets: shapes of spherical topology and shapes of non-spherical topology experience respectively a deviatoric bending contribution a la Fischer and a mean curvature bending contribution a la Helfrich. In other words, topology may be considered to describe bending phenomena. Besides, we calculate the bending energy per genus and the bending closure energy regardless of the shape of the vesicle. As an illustration we briefly consider geometrical frustration phenomena experienced by magnetically coated vesicles.Comment: 8 pages, 1 figure; LaTeX2e + IOPar
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