Abstract

  Bivariate time series modeling and forecasting have become a promising field of applied studies in recent times. For this purpose, the Linear Autoregressive Moving Average with exogenous variable ARMAX model is the most widely used technique over the past few years in modeling and forecasting this type of data. The most important assumptions of this model are linearity and homogenous for random error variance of the appropriate model. In practice, these two assumptions are often violated, so the Generalized Autoregressive Conditional Heteroscedasticity (ARCH) and (GARCH) with exogenous varia

To create a highly efficient photovoltaic-thermal (PV-T) system and maximise the energy and exergy efficiency, this study aims to propose an innovative configuration of a PV-T system comprising wavy tubes with twisted-tape inserts. Following the validation of a numerical model, a parametric study has been conducted to assess the geometrical effects of twisted tape and wavy tubes, as well as the coolant fluid type and velocity, on the overall performance of a PV-T system, located in Shiraz, Iran. It is found that employing twisted tape improves the energy and exergy efficiency by approx. 6.3%. The best configuration yields 12.4% and 16.8% increase in energy and exergy efficiency compared to conventional PV systems. This is achieved at 15% vo

Polarization manipulation elements operating at visible wavelengths represent a critical component of quantum communication sub-systems, equivalent to their telecom wavelength counterparts. The method proposed involves rotating the optic axis of the polarized input light by an angle of 45 degree, thereby converting the fundamental transverse electric (TE0) mode to the fundamental transverse magnetic (TM0) mode. This paper outlines an integrated gallium phosphide-waveguide polarization rotator, which relies on the rotation of a horizontal slot by 45 degree at a wavelength of 700 nm. This will ultimately lead to the conception of a mode hybridization phenomenon in the waveguide. The simulation results demonstrate a polarization co

Many oil and gas processes, including oil recovery, oil transportation, and petroleum processing, are negatively impacted by the precipitation and deposition of asphaltene. Screening methods for determining the stability of asphaltenes in crude oil have been developed due to the high cost of remediating asphaltene deposition in crude oil production and processing. The colloidal instability index, the Asphaltene-resin ratio, the De Boer plot, and the modified colloidal instability index were used to predict the stability of asphaltene in crude oil in this study. The screening approaches were investigated in detail, as done for the experimental results obtained from them. The factors regulating the asphaltene precipitation are different fr

The concept of privatization is built on the basis of the transfer of assets and services of the public sector to the private sector this concept has appeared in the eighties of the last century whene the high oil prices took place and recession solution swept the world Which called for the freedom of the market and left the room for the private sector to take the initiatine in economic activity.         Both the IMF have   adopted this thesis in their programs of the structural adjustment in light of external and internal factors helped to Create the conditions to accept thesis that under the pretext of achieving a number of economic goals.

In Iraq in spite of

Wielands Hauptwerk die Geschichte des Agathon (1766/73,1794) ist

der wichtigste Roman der Aufklärungsepoche (1720-1785). Die Verlegung der

Handlung in die Antike widerspiegelt die kulturelle Blüte der vorbildhaften Zeit

zwischen 5. und 4. Jhd. v. Chr.

Beim Lesen des Romans findet man unzählige (über 70) Namen aus der

Antike; von Herrschern, Strategen, Philosophen, Dichtern, Künstlern . . . etc,

woüber man unbedingt informiert werden muss, um deren Zusammenhang in der

Geschichte zu verstehen. Vorübergehend erwähnte Personennamen gibt Wieland

meistens als Beispiel für eine Situation oder ein Verhalten. Dies gab mir den

Anstoß, die wichtigsten Figuren

Business incubator is a new effective mechanism in developing small projects through its introductions of a new integral system of services. It aims at supporting and developing making new projects. Hence, there is a big number of factors that are interrelated in the processes of preparation for those projects. Those factors are: organizing the incubator and the market available for the projects attached to them and the work programs which will have to be implemented. Those small projects represent more than 98% of the total work institutions in the world. Also it has become responsible for a ration reaching half of the national output of those countries. These projects have created between 40 to 80% of job opportunities availabl