External Debt Accumulation and Its Impact on Economic Growth in Pakistan

The accumulation of external debt is common phenomenon of the developing countries and it has become a common feature of the fiscal sectors of most of the economies. A country with lower saving rate needs to borrow more to finance the given rate of economic growth. So external debt is obtained to sustain the growth rate of the economy, which is otherwise not feasible with the given domestic resources. Pakistan is one of the developing countries and faces serious debt problems, according to World Bank Report 2000-2001, Pakistan is among the Highly Indebted Countries (HICs); because Pakistan’s present and future debt situation is very grim. According to the World Bank total external debt may be defined as debt owed to non-resident repayable in terms of foreign currency, goods or services. External debt is the composition of long term debt (public and publicly guaranteed debt plus private non guaranteed debt), short term commercial debt and International Monetary Fund (IMF) loans. Prior to early 1970s the external debt of developing countries was primarily small and official phenomenon, the majority of creditors being foreign governments and international financial institutions offer loan for development project [Todaro (1988)]. At the same time current account deficit was common which increased the external indebtedness of the developing countries, until when Mexico, despite an oil exporter, declared in august, 1992 that it could not services its debt ever since, the issue of external debt and its servicing has assumed critical importance and introduced the debt crises debate [Were (2001)]

Engine oil based MoS2Casson nanofluid flow with ramped boundary conditions and thermal radiation through a channel

The modern era is a time to have cost-effective and energy-efficient technology. This demand has made nanotechnology the most effective field. The focus of this article is to increase the efficiency of engine oil (EO). The flow of EO-based Casson nanofluid containing Molybdenum disulfide (MoS2) nanoparticles is investigated with ramped wall conditions and thermal radiation. Analytical results are calculated via the Laplace transform. The impact of physical parameters on isothermal and ramped conditions is illustrated graphically and discussed in detail. The researchers found that flow, mass, and energy can be controlled by using ramped conditions. The variation in concentration, temperature, and velocity is exponential for isothermal conditions and steady for ramped wall conditions. Finally, the results of Nusselt numbers, skin frictions, and Sherwood numbers on both walls of the channel for both isothermal and ramped conditions are graphically depicted and discussed. For higher values of time the results of ramped and isothermal wall conditions are identical. It is found that the nanoparticles of MoS2 enhance the lubrication and heat transport rates of EO.The authors would like to express the gratitude to Deanship of Scientific Research at King Khalid University , Saudi Arabia for providing funding research group under the research grant number R.G.P. 2/51/43 . Open Access funding provided by the Qatar National Library .Scopu

Low-profile antenna system for cognitive radio in IoST CubeSat applications

Since the CubeSats have become inherently used for the Internet of space things (IoST) applications, the limited spectral band at the ultra-high frequency (UHF) and very high frequency should be efficiently utilized to be sufficient for different applications of CubeSats. Therefore, cognitive radio (CR) has been used as an enabling technology for efficient, dynamic, and flexible spectrum utilization. So, this paper proposes a low-profile antenna for cognitive radio in IoST CubeSat applications at the UHF band. The proposed antenna comprises a circularly polarized wideband (WB) semi-hexagonal slot and two narrowband (NB) frequency reconfigurable loop slots integrated into a single-layer substrate. The semi-hexagonal-shaped slot antenna is excited by two orthogonal +/−45° tapered feed lines and loaded by a capacitor in order to achieve left/right-handed circular polarization in wide bandwidth from 0.57 GHz to 0.95 GHz. In addition, two NB frequency reconfigurable slot loop-based antennas are tuned over a wide frequency band from 0.6 GHz to 1.05 GH. The antenna tuning is achieved based on a varactor diode integrated into the slot loop antenna. The two NB antennas are designed as meander loops to miniaturize the physical length and point in different directions to achieve pattern diversity. The antenna design is fabricated on FR-4 substrate, and measured results have verified the simulated results

Finite Element Analysis of the Dynamics of Power-Law Fluid around an Obstacle in a Channel

Control of uid forces is an emerging area of research with numerous engineering applications. ­e uneven wake behind an obstacle causes undesirable structural oscillations, which can lead to fatigue or structural failure. Controlling the wake phenomena could directly bene t a wide range of engineering applications, including skyscrapers, naval risers, bridges, columns, and a few sections of airplanes. ­is study is concerned with the time dependent simulations in a channel in presence of an obstacle aiming to compute uid forces. ­e underlying mathematical model is based on nonstationary Navier–Stokes equations coupled with the constitutive relations of power law uids. Because the representative equations are complex, an e ective computing strategy based on the nite element approach is used. To achieve higher accuracy, a hybrid computational grid at a very ne level is used. ­e P2 − P1 elements based on the shape functions of the second and rst-order polynomials were used to approximate the solution. ­e discrete nonlinear system arising from this discretization is linearized by Newton’s method and then solved through a direct linear solver PARADISO. ­e code validation study is also performed for Newtonian uids as a special case, and then the study is extended to compute drag and lift forces for other cases of viscosity as described by the power law index. When looking at the phase plot, it can be seen that for the Newtonian case n 1, there is only one closed orbit after the steady state is reached, whereas for n 0.5, there are multiple periodic orbits. Moreover, the e ects of shear rate on the drag-lift phase plot are also discussed.Scopu

Adsorption Properties of Coriander Seed Powder (): Extraction and Pre-concentration of Pb(II), Cu(II) and Zn(II) Ions from Aqueous Solution

Coriander seed powder has been shown to exhibit a remarkable adsorption potential towards Pb(II), Cu(II) and Zn(II) ions from aqueous solution, with the adsorption capacities following the order Pb(II) > Cu(II) > Zn(II). The influences of pH, initial metal ion concentration, adsorbent dosage and contact time on the process were investigated. The adsorption data at different temperatures were well fitted by the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) model isotherms. The kinetic data obeyed the pseudo-second-order kinetic model. The thermodynamic parameters showed that the adsorption of Pb(II) ions was endothermic and spontaneous. Competitive adsorption in the Pb(II)–Cu(II) and Pb(II)–Zn(II) systems was also studied. The breakthrough capacities of Pb(II), Cu(II) and Zn(II) ions in single metal ion systems were higher than in multi-metal ion systems. The analytical application of the adsorption process was demonstrated by the removal of Pb(II) ions from the wastewater derive from the manufacture of lead acid batteries. Excellent results were obtained when desorption of the studied metal ion from very dilute solution was effected by column methods. Hence, these methods were further utilized for the extraction and pre-concentration of Pb(II), Cu(II) and Zn(II) ions from very dilute synthetic mixtures of these metal ions prepared in doubly distilled water as well as in tap water to enable their subsequent determination by atomic absorption spectrometry

Adsorption studies of Cd(II) on ball clay: Comparison with other natural clays

Ball clay was found to exhibit excellent adsorption capacity toward Cd(II) ions over a wide concentration range. The adsorption capacity was studied by heating it at different temperatures. It was found that the sample heated at 200 °C showed maximum adsorption capacity toward Cd(II) ions. This research was focused on the effect of pH, time, temperature, adsorbent doses and initial Cd(II) concentration by batch experiments. The equilibrium data of Cd(II) adsorption were explained well by Langmuir and Freundlich adsorption isotherms. The kinetics data for the adsorption process obeyed pseudo-first-order and pseudo-second-order models at lower initial concentrations of Cd(II) while with the increased concentration of Cd(II) pseudo-first-order model failed. The Cd(II) desorption was performed using batch process with various desorbing solutions and 100% desorption was achieved with HCl solution

Geometric inequality of warped product semi-slant submanifolds of locally product Riemannian manifolds

In the present article, we derive an inequality in terms of slant immersions and well define warping function for the squared norm of second fundamental form for warped product semi-slant submanifold in a locally product Riemannian manifold. Moreover, the equality cases are verified and generalized the inequality for semi-invariant warped products in locally Riemannain product manifold

Duality for Unified Higher-Order Minimax Fractional Programming with Support Function under Type-I Assumptions

This article is devoted to discussing the nondifferentiable minimax fractional programming problem with type-I functions. We focus our study on a nondifferentiable minimax fractional programming problem and formulate a higher-order dual model. Next, we establish weak, strong, and strict converse duality theorems under generalized higher-order strictly pseudo ( V , α , ρ , d ) -type-I functions. In the final section, we turn our focus to study a nondifferentiable unified minimax fractional programming problem and the results obtained in this paper naturally unify. Further, we extend some previously known results on nondifferentiable minimax fractional programming in the literature