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Smoothed particle hydrodynamics is a typical Lagrangian meshless method, which has unique advantages in modelling multiphase phenomena with interface deformation and fragmentation. Current study proposes a comprehensive multiphase SPH model, which takes the advantages of some numerical techniques such as numerical interfacial force and damping technique. An improved boundary model is also introduced to deal with the solid walls. Additionally, the multiphase phenomena are investigated by solving an enhanced continuous surface force (CSF) model. In order to verify the proposed model, the droplet in shear flow is firstly considered and the results are consistent with the analytical solutions. Furthermore, the oscillations of square droplets are simulated under different particle resolutions, density and viscosity ratios. Finally, two and three dimensional bubble rising at high density ratios (up to 1000) are tested.

This paper reports on a novel technique of switching radiation characteristics electronically between E- and H-planes of planar Substrate Integrated Waveguide Leaky Wave Antennas (SIW-LWAs). The leaky wave mode is achieved through increasing the pitch of bounding metallic via posts on one side of SIW transmission section. The radiation switching is achieved by extending the top and bottom metallic planes to a distance of 1 mm along the leakage side. The extended section acts as a parallel plate section which is conveniently connected or disconnected from the leaking side of SIW through PIN diodes. The `ON' state of PIN diodes extends the metal guides and results in the H-plane leakage whereas `OFF' state of PIN diodes truncates the extended metal earlier and alter the leakage line boundary condition towards E-plane. The whole concept is validated by series of simulations followed by the realization and testing of the SIW-LWA. The measured radiation pattern scans about 54° in the E-plane between 10.0 GHz to 11.7 GHz, and 58° in the H-plane from 9 GHz to 10.6 GHz. The proposed topology is a suitable candidate for remote sensing and airborne applications.

This study investigates the role of exchange rate, market size and human capital for attracting foreign direct investment (FDI). In this regard, time series data on annual basis has been collected for the period 1985–2010 and an Augmented Dickey–Fuller (ADF) and Phillips–Perron (PP) unit root tests are utilized to determine the stationarity of the variables. An autoregressive distributed lag (ARDL) bounds testing approach to co-integration was applied as all the variables in the model are first level stationary,e.g. I(1). The empirical findings of this study confirm the long run relationship among the variables. However, market size and human capital have strong positive and significant impact – in short- and long-run – for attracting FDI but exchange rate shows negative impact in this regard. The coefficient ECM is negative and significant, which means that it converges towards equilibrium. CUSUM and CUSUMSQ tests were utilized to test the model’s stability and the plots of each test did not cross the lines of critical value, which indicates the stability of the estimated parameters and this model can be used by Pakistan in policy and decision making. For achieving higher economic growth and economies of scale, the country should concentrate on the ingredients of this study so that it could attract more FDI as compared to the other countries.

Derivatives are the major icon among risk management practices. Firms usually use derivatives to hedge their foreign exchange and interest rate risk. This study aims to examine the determinants’ of corporate hedging policies and derivative usage in risk management particularly with respect to Pakistan, as the political and economic conditions in Pakistan are highly volatile which intends the corporations to handle and mitigate their risk through channelizing the derivatives. Secondary data of 75 non financial firms listed in Karachi Stock Exchange was collected over the period 2007-2011 – to regress empirically – for achieving the aim of this study. Mann-Whitney U test was used to distinguish the derivative user and non user. Findings of this test characterize users as large size, higher growth opportunities, cash flow volatility, foreign exchange and interest rate exposure. Moreover this study finds that there is a significant relationship between the use of derivatives and foreign purchase, liquidity, firm growth and size. Our findings suggest that derivative users have competitive edge over the non user, as they get economies of scale and proper risk management through using these kinds of derivative instruments.

Software (SW) development is a very tough task which requires a skilled project leader for its success. If the project leader is not skilled enough then project may fail. In the real world of SW engineering 65% of the SW projects fail to meet their objectives as in [1]. The main reason is lack of training of the project mangers. This extreme ratio of failure can be reduced by teaching SW project management (SPM) to the future project managers in the practical manner, so that they may be skillful enough to handle the project in a better way. This paper intends to propose a model to be used to teach SPM to the student of SW engineering to reduce the failure rate of projects., Comment: 9 Pages; ISSN: 1013-5316, CODEN: SINTE 8