Scheduling considered being one of the most fundamental and essential bases of the project management. Several methods are used for project scheduling such as CPM, PERT and GERT. Since too many uncertainties are involved in methods for estimating the duration and cost of activities, these methods lack the capability of modeling practical projects. Although schedules can be developed for construction projects at early stage, there is always a possibility for unexpected material or technical shortages during construction stage. The objective of this research is to build a fuzzy mathematical model including time cost tradeoff and resource constraints analysis to be applied concurrently. The proposed model has been formulated using fuzzy theory combining CPM computations, time-cost trade off analysis and resource constraint. MATLAB software has been adopted to perform ranking process, for each case, that
facilitates obtaining the optimum solution. This research infers that it is possible to perform time-cost trade off analysis with resource restriction simultaneously, which ensures achieving scheduling optimum solution reducing the effort and the time when performing these techniques in succession using traditional methods.
أن أهمية البحث تكمن في أعداد منهج تعليمي مقترح وفق أنموذج بايبي وتعلم مهارتي الاعداد وأستقبال الارسال بالكرة الطائرة للطالبات وتكمن أهمية أنموذج بايبي بالمساعدة على توظيف المعلومات في المواقف المختلفة،وان مشكلة البحث جاءت بعد أطلاع الباحثات على الدراسات والمصادر السابقة لاحظت بأن هناك ضعف في الاداء المهاري في مهارتي الاعداد وأستقبال الارسال بالكرة الطائرة من قبل الطالبات لذلك أرتأت الباحثات الى التع
... Show MoreThe undimensionality hypothesis which is item response theory depend it is unable in some of measurement situations because there are many dimensions which are affect of the response, so as the researches reached to expand this hypothesis to construct a new one which is multidimensional, and many of theories are pointed to the concept of meaning of life is multidimensionality, so this research aimed to construct the scale of meaning of life as the student's perception according with Multidimensional Item Response Model and this research adopt Wong's theory 1998 which point to the meaning of life consist of (7) dimensions. The research tool contains (49) items distributed at dimensions of meaning of life. Sample of statistical ana
... Show MoreThe accuracy of IRI- 2012 and VOACAP models during high solar activity level have been tested to know which of them is more accurate in predicting hourly foF2 values for three Iraqi cities (Baghdad, Mosul and Basrah). The results indicated that the accuracy of them increases for all hours during Spring and Summer and decreases during Winter and Autumn especially at hours near to sunrise; i.e., both of two models have the same accuracy. And that the foF2 values predicted by VOACAP model are higher than that predicted by IRI- 2012 model for all seasons.
In this paper, a mathematical model consisting of the prey- predator model with disease in both the population is proposed and analyzed. The existence, uniqueness and boundedness of the solution are discussed. The existences and the stability analysis of all possible equilibrium points are studied. Numerical simulation is carried out to investigate the global dynamical behavior of the system.
This study presents the findings of a 3D finite element modeling on the performance of a single pile under various slenderness ratios (25, 50, 75, 100). These percentages were assigned to cover the most commonly configuration used in such kind of piles. The effect of the soil condition (dry and saturated) on the pile response was also investigated. The pile was modeled as a linear elastic, the surrounded dry soil layers were simulated by adopting a modified Mohr-Coulomb model, and the saturated soil layers were simulated by the modified UBCSAND model. The soil-pile interaction was represented by interface elements with a reduction factor (R) of 0.6 in the loose sand layer and 0.7 in t
Necessary and sufficient conditions for the operator equation I AXAX n*, to have a real positive definite solution X are given. Based on these conditions, some properties of the operator A as well as relation between the solutions X andAare given.
Regression Discontinuity (RD) means a study that exposes a definite group to the effect of a treatment. The uniqueness of this design lies in classifying the study population into two groups based on a specific threshold limit or regression point, and this point is determined in advance according to the terms of the study and its requirements. Thus , thinking was focused on finding a solution to the issue of workers retirement and trying to propose a scenario to attract the idea of granting an end-of-service reward to fill the gap ( discontinuity point) if it had not been granted. The regression discontinuity method has been used to study and to estimate the effect of the end -service reward on the cutoff of insured workers as well as t
... Show MoreA flexible pavement structure usually comprises more than one asphalt layer, with varying thicknesses and properties, in order to carry the traffic smoothly and safely. It is easy to characterize each asphalt layer with different tests to give a full description of that layer; however, the performance of the whole; asphalt structure needs to be properly understood. Typically, pavement analysis is carried out using multi-layer linear elastic assumptions, via equations and computer programs such as KENPAVE, BISAR, etc. These types of analysis give the response parameters including stress, strain, and deflection at any point under the wheel load. This paper aims to estimate the equivalent Resilient Modulus (MR) of the asphalt concrete
... Show MoreSpectral and linear optical properties for a mixture of Rhodamine B (RB) and Fluorescein Sodium (Na Fl) organic laser dyes were determined at different concentrations 10-3, 10-4 M in ethanol solvent at room temperature. The intensity of absorption range is towards longer wavelengths (red shift). The quantum efficiency diminished while the radiative and fluorescence life time increased when increment concentration, organic laser dyes have a spectrum within the range 540-500 nm. Results demonstrate that a mixture of laser dyes are effective optical materials when contrasted with individual laser dyes. It can be utilized as resonator in cavity lasers.
Our goal from this work is to find the linear prediction of the sum of two Poisson process
) ( ) ( ) ( t Y t X t Z + = at the future time 0 ), ( ≥ + τ τ t Z and that is when we know the values of
) (t Z in the past time and the correlation function ) (τ βz