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A constitutive law can be defined as a mathematical functional relation between physical quantities such as stress and strain and may take other factors like time ,temperature and additional material properties into account. In this paper , the endochronic model is used to predict the stress-strain relations of two Iraqi clays. This model is a viscoplastic one but without introducing a yield surface. It encompasses material behaviour such that the current stress state is a function of strain history through a time scale called “intrinsic time” which is not the absolute time but a material property. The simulation showed that the model overestimates the strains for all cases studied. This may be attributed to the material parameters which require a parametric study to determine their actual values for Iraqi clays

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The lane changing model is one of the most important cornerstone models to build a traffic microscopic simulation model. To build such lane changing model, there is a need to investigate the drivers’ characteristics from field data. Accordingly, this study has mainly focused on lane changing behavior of Iraqi drivers. A huge amount of data has been collected from different sites in Iraq using specific type of cameras; these five sites (roads) are: Baghdad–Hilla, Baghdad–Mahmudiyah, Baghdad-Kut, Baghdad–Diyala and Najaf- Karbala roads. In addition, gun-speed has been also used to collect data of desired speeds. Different data have also been collected such as flow, headway, and speeds. The results show that as the flow increases, the frequency of lane changing also increases up to specific range of flow then as flow increases the frequency of lane changing decreases. In addition, this study indicates higher number of lane changing over all observed sites comparing with other countries. Finally, this study also indicates that the violated number of lane change varies with different levels of flow.

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We have calculated some of the basic structural properties such as the ground state proton, neutron and matter densities and elastic form factors of halo nuclei namely, 11Be and 14Be using the binary cluster model (BCM) within the Gaussian and harmonic oscillator wave functions. The halo nuclei have been considered as a compact core with loosely bound valence neutron(s) forming the halo. The comparison between the calculated and experimental matter density distributions supports the halo structure for 11Be [14Be] where the valence one neutron [two neutrons] occupy the 1p1/2 [(2s1/2)2] orbital. We have also calculated the reaction cross sections (σ_R ) for these nuclei using the Glauber model with an optical limit approximation at low and high energies. The calculated (σ_R ) of these nuclei give a good description of experimental data at both low and high energies.

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River engineering investigations require some level of hydrodynamic and morphologic analysis. The detailed of the hydraulic and morphologic features through meander evolution can be recorded by the numerical model spatially and temporally. The Center for Computational Hydro-science and Engineering, two- dimensional model (CCHE2D V3.29) was adopted to investigate the hydraulic and morphologic changes through meander’s evolution. Through the experimental work, a series of experiments runs were carried out through combining different geometric and hydraulic parameters to produce different experiment conditions. These parameters are flow rate, bed slope, and different initial incised and wide channels for both rectangular and trapezoidal sections. The CCHE2D model was calibrated and verified using two sets of experimental data. According to the computed values of statistical indicators, BIAS, NSE, and MAE of 0.0084, 0.96, and 0.0132 respectively for water level simulation, and 0.007,0.94, and 0.0182 respectively for bed level simulation, the calibrated Manning’s roughness which gives an acceptable agreement between simulated and measured water and bed levels was 0.029. The verification results were evaluated by the same statistical indicators of BIAS, NSE, and MAE of 0.09, 0.81, and 0.018, respectively, as evidenced by the statistical indicators, values that the CCHE2D model was reasonably capable of simulating the hydraulic and morphological changes through meander evolution.

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: In last decades the applications of the computerized system were widely used in various environments, such real time systems, monitoring system and other. These applications need live answer from the programmable system. The compiler phases represent the heart of any programming language, therefore if we enhance the compilers; we make the execution more efficient.
In this paper we present new model for SLR-Parser, which is the main stage of the compiler phases, because it responsible for the grammatical checking of the program statements and it needs more time than other stages. The new model appears faster than original parse. Also it is less complexity than original parser. Therefore, it is more efficient to use.

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The purpose of this research is to design and implement a new DiscreteWavelet Transform (DWT) encoder/decoder for speech compression. Three compressionprocedures are suggested these are, Wavelet Analysis-Synthesis, Wavelet GlobalThreshold and Wavelet By-Level Threshold. The major issues concerning the design ofthis Wavelet based speech coder are proposed mother wavelet for speech signal,decomposition level in DWT, threshold criteria for coefficient truncation and efficientencoding of truncated coefficients. Performances of these three procedures are comparedand the encoded methods are evaluated based on compression ratio and signal to noiseratio factors.

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Abstract This research includes study the importance of using logistic regression model to predict the functions with Economic categorical Dependent variables, to get rid of the statistical and conceptual problems Facing the use of the least squares method, and for that we select 25 developing countries as a sample for research, depending on the World Bank and UN data, with the help of statistical package SPSS17. The importance of research is trying to explain that analysis tools, of a limited use now, to enrich the quantitative analytical tools are currently known in the Arab economic literature, especially after the growing need to adopt a qualitative variables as dependent variables, which requires to use appropriate analytical tools. The most important conclusion of the research is that the use of binary logistic regression model with binary dependent variables are eliminated from the three Econometrics problems, because it is passing the tests of Autocorrelation , Multicollinearity and Heteroscedasticity.

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Abstract This research aims to estimate the (ARIMA) model of the problem of unemployment in Egypt by using statistical data which is available on the internet for the period from 1990 to 2010 and future forecasting about unemployment which is determined about 9.7350 million in 2017.

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The aim of this study is to know the effectiveness of implementing type (Wheatley) model the constructional model in the achievement of learning and the eighth basic class students attitude toward biology . the sample of study consisted of the eighth basic class students, in' Damascus' province. The number of these students was (70) students ,distributed on two classes: The first experimental class included (35) students taughtbytheimplementationoftype"Wheatley"the constructional. The second control group consisted of (35) students taught according to the ordinary classic methods .The researcher made an achievement test and an attitude test toward biology in order to evaluate the extent of benefitting from methods implemented in teaching each of the two classes. The study reached many results. The most important ones are : 1.The existence of difference with a statistic indication among the means of students grades of the two classes in favour of the experimental group at the indication level of (0,05) in the post –achievement test .2. The existence of difference with a statistic indication among the means of students grades in the pre-test and post- test of the experimental group , in favour of the post – test at the indication level of (0,05), confirming the effectiveness of implementing the constructional "Wheatley" type in teaching biology to eighth basic class scientific section. 3. The existence of difference with a statistic indication among the means of students tendencies grades of both experimental group and criterion group , in favourof the experimental group taught according to the constructional "Wheatley" type and this confirms the effectiveness of "Wheatley " type increasing tendency toward biology ,at indication level of(0,05).4. The existence of difference with a statistic indication among the means of students tendencies grades of experimental group in the pre-test and post- test , in favourof the post-test this confirms the effectiveness of "Wheatley " type increasing tendency toward biology ,at indication level of (0,05).Key words : "Wheatley " type .

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Micro -EDM is one of an important method in machining holes which is used in wideapplications to fabricate medical devices and small dies. This work study the process ofproducing micro holes for copper alloy workpieces using, stainless steel electrodeand dielectric solution (tap water), using DC current and low voltage (70V) to cut(0.7mm) thickness of copper (Cu) alloy workpieces in order to obtain the micro holes.This work included an experimental work for electrical discharge machining(EDM) to produce micro holes with different diameters (400, 300, 210, 200, 120,100, 85, 75, 70) μm.The objective of this work is to obtain an optimal setting of EDM parameters toproduce micro holes in copper alloy to achieve the optimal values of required holesdiameters.A regression model has been developed to represent this process. An approachhas been made to optimize the process parameters (current, gap distance, machiningtime) using ANOVA analysis. This analysis was performed to obtain the mostsignificant factors influencing the production of micro holes.

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