Atmospheric stability plays the most important role in the transport and dispersion of air pollutants. Different methods are used for stability determination with varying degrees of complexity. Most of these methods are based on the relative magnitude of convective and mechanical turbulence in atmospheric motions, such as Richardson number, Monin-Obukhov length, Pasquill-Gifford stability classification and Pasquill-Turner stability classification. The Pasquill-Turner Method (PTM), which is employed in this study used Observations of wind speed, solar altitude angle and the time of day to classify atmospheric stability with distinguishable indices. As a case study, meteorological data that gathered from European Centre For Medium-Range W

     In this paper we investigate the stability and asymptotic stability of the zero solution for the first order delay differential equation

     where the delay is variable and by using Banach fixed point theorem. We give new conditions to ensure the stability and asymptotic stability of the zero solution of this equation.

The aim of this work is to study a modified version of the four-dimensional Lotka-Volterra model. In this model, all of the four species grow logistically. This model has at most sixteen possible equilibrium points. Five of them always exist without any restriction on the parameters of the model, while the existence of the other points is subject to the fulfillment of some necessary and sufficient conditions. Eight of the points of equilibrium are unstable and the rest are locally asymptotically stable under certain conditions, In addition, a basin of attraction found for each point that can be asymptotically locally stable. Conditions are provided to ensure that all solutions are bounded. Finally, numerical simulations are given to veri

No country in the world has an ancient heritage of its own. It represents the product of the civilizations left behind by previous eras. It represents the development of urban life and its capital of the interest of its people in the field of construction and reconstruction. The urban heritage and its associated arts may seem to be a material heritage at first glance, but it is not free from the spiritual side. Therefore, the nations in different parts of the earth cherish it and care for it with all due diligence, because it mixes with its history, memories and emotions.
This research discusses the use of local environment materials in the production of urban fabric constituents. I

In this research, the influence of the distance factor on the optimal working
frequency (FOT) parameter has been studied theoretically for the ionosphere layer
over the Middle East Zone. The datasets of the (FOT) parameter have been
generated using the (VOACAP) model which considers as one of the recommended
modern international communication models that used to calculate the ionosphere
parameters. The calculations have been made for the connection links between the
capital Baghdad and many other locations that distributed on different distances and
directions over the Middle East region. The years (2011-2013) of the solar cycle 24
have been adopted to study the influence of the distance factor on the FOT
param

     Atenolol was used with ammonium molybdate to prove the efficiency, reliability and repeatability of the long distance chasing photometer (NAG-ADF-300-2) using continuous flow injection analysis. The method is based on reaction between atenolol and ammonium molybdate in an aqueous medium to obtain a dark brown precipitate. Optimum parameters was studied to increase the sensitivity for developed method. A linear range for calibration graph was 0.1-3.5 mmol/L for cell A and 0.3-3.5 mmol/L for cell B, and LOD 133.1680 ng/100 µL and 532.6720 ng/100 µL for cell A and cell B respectively with correlation coefficient (r) 0.9910 for cell A and 0.9901 for cell B, RSD% was lower than 1%, (n=8) for the determination of ate

Benthic invertebrates were used as bio- indicators to evaluate the pollution in -Diwania River . Five stations were selected for this purpose , extending from A1 -?? rtream to A1- Sadeer District downstream . The percentage of?ct uP?str?^ ? ?, oligochaeta to total benthic invertebrates were calculated . The population density of evaluation. 'I'he results Were ??? Tubificid worms without hair ehaetae was ©iso used IOBS(01igochaete Index of Sediment Bioindicati©n ), TUSP ? presented as indices Io (Tubificidae Species Percentage ) & degree of pollution Eo . IT was noticed that the 0 in??37.17 percentage of ©lig©chaeta to the total benthic invertebrates ranged between to 60.685 in station 3 , while the percentage ©f Tubificid w©rms t© ©

                 The research deals with the concept of a New Urbanism as an urban development strategy in the suburbs of cities or in its centers that are affected by pedestrian-oriented design and the possibility of walking, as well as integrating economic classes through the diversity of housing and its costs, and this works to facilitate access to jobs and services while providing more diverse neighborhoods and reducing the use of cars , As designing separate houses in the suburbs and increasing car trips poses a threat to the environment and the quality of urban life, and thus the new urban provides a good strategy for developing

The mechanical function of the heart is governed by the contractile properties of the cells, the mechanical stiffness of the muscle and connective tissue, and pressure and volume loading conditions on the organ. Although ventricular pressures and volumes are available for assessing the global pumping performance of the heart, the distribution of stress and strain that characterize regional ventricular function and change in cell biology must be known. The mechanics of the equatorial region of the left, ventricle was modeled by a thick-walled cylinder. The tangential (circumferential) stress, radial stress and longitudinal stress in the wall of the heart have been calculated. There are also significant torsional shear in the wall during b