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Synthesis and Mesomorphic Behavior of Two New Homologous Series Containing Azobenzene and 1,3,4-Oxadiazole Units
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Two new nonsymmetrical mesogenic homologous series of terminal substituent ether (series [Vn]) and carboxy (series [VIn]) incorporating azobenzene and 1,3,4-oxadiazole group were synthesized. Both series have been All compounds thus isolated were purified and characterized by elemental analysis, Fourier Transform Infrared Spectroscopy, 1H NMR, along with thermal analysis and texture observation using Differential Scanning Calorimetry (DSC) and Polarizing Optical Microscopy (POM), respectively. All compounds of the first series exhibited liquid crystalline properties. The homologues [V1]-[V3] display a nematic mesophase, the compounds [V4]-[V7] exhibit a dimorphism behavior, nematic (N) and smectic A (SmA) mesophases, the compounds [V8] and [VI9] display enantiotropic smectic A and C (SmA and SmC) phases and the last homologue [V12] exhibits only a smectic C mesophase. All compounds of the second series [VIn] also show mesomorphic behavior, the compounds [VI1]-[VI3] and [VI5] display the nematic mesophase, the homologue [VI7] exhibits dimorphism behavior, nematic, and smectic A (SmA). The mesomorphic behavior has been analyzed in terms of structural property relationships.

Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Denotation of Stanza and couplet between the two sonnets
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The stanza in the sonnet has been defined as a set of poetic lines followed after proem
and be the same meter as that of proem in complete stanza, but in rhyme scheme different
from that meter. The couplet is defined as set of poetic lines that followed the stanza and be as
the same meter as that of stanza, but with different rhyme scheme. This definition is approved
by all specialized in field of Andalus literature and it was also proven to them that this
construction emptied of indications. This meter has endeavored to prove that that there were a
difference in denotation for meaning between the stanza and couplet. Thus, the sonneteers
have outweighed the sonnet of the blind "Tutaili" to their sonnets as they felt

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Performance quality of single and ?two stage solar concentrators
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The performance of single and two stage solar concentrator were studied ' " The ratio of the primary to the secondary mirrors diameter is taking to be 0.5, depending on the theoretical calculation for the accumulated energy by the concentrator with ratio between 0.0 to 0.9. The design of the systems were designed and examined by using a ray-tracing program. The efficiency of the single and the two stage concentrators are calculated and compared with and without cooling systems.

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Publication Date
Tue May 23 2023
Journal Name
Journal Of Engineering
EXPERIMENTAL AND THEORETICAL STUDY OF TWO-PHASE HEAT PIPE
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In this study, thermal characteristics of a two-phase closed heat pipe were investigated experimentally and theoretically. A two-phase closed heat pipe (copper container, Fluorocarbon FC-72 (C6F14) working fluid) was fabricated to examine its performance under the effect of input heat flux range of 250–1253 W/m2 , 70% fill charge ratio and various tilt angles. The temperature distribution along the heat pipe, input heat to evaporator section, and output heat from condenser were monitored. A comprehensive mathematical model was developed to investigate the steadystate heat transfer performance of a two-phase closed heat pipe. A steady state analytical model, is presented to determine important parameters on the design of two-phase close

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Publication Date
Fri Mar 29 2024
Journal Name
Iraqi Journal Of Science
Evaluating the Performance and Behavior of CNN, LSTM, and GRU for Classification and Prediction Tasks
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     Deep learning (DL) plays a significant role in several tasks, especially classification and prediction. Classification tasks can be efficiently achieved via convolutional neural networks (CNN) with a huge dataset, while recurrent neural networks (RNN) can perform prediction tasks due to their ability to remember time series data. In this paper, three models have been proposed to certify the evaluation track for classification and prediction tasks associated with four datasets (two for each task). These models are CNN and RNN, which include two models (Long Short Term Memory (LSTM)) and GRU (Gated Recurrent Unit). Each model is employed to work consequently over the two mentioned tasks to draw a road map of deep learning mod

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Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Between the Methods Estimate Nonparametric and Semiparametric Transfer Function Model in Time Series Using Simulation
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Publication Date
Wed May 03 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Time Series Forecasting by Using Box-Jenkins Models
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    In this paper we introduce a brief review about Box-Jenkins models. The acronym ARIMA stands for “autoregressive integrated moving average”. It is a good method to forecast for stationary and non stationary time series. According to the data which obtained from Baghdad Water Authority, we are modelling two series, the first one about pure water consumption and the second about the number of participants. Then we determine an optimal model by depending on choosing minimum MSE as criterion.

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Publication Date
Wed Aug 30 2023
Journal Name
Iraqi Journal Of Science
Network Traffic Prediction Based on Time Series Modeling
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    Predicting the network traffic of web pages is one of the areas that has increased focus in recent years. Modeling traffic helps find strategies for distributing network loads, identifying user behaviors and malicious traffic, and predicting future trends. Many statistical and intelligent methods have been studied to predict web traffic using time series of network traffic. In this paper, the use of machine learning algorithms to model Wikipedia traffic using Google's time series dataset is studied. Two data sets were used for time series, data generalization, building a set of machine learning models (XGboost, Logistic Regression, Linear Regression, and Random Forest), and comparing the performance of the models using (SMAPE) and

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Publication Date
Sun May 17 2020
Journal Name
Iraqi Journal Of Science
Solving Fuzzy Differential Equations by Using Power Series
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In this paper, the series solution is applied to solve third order fuzzy differential equations with a fuzzy initial value. The proposed method applies Taylor expansion in solving the system and the approximate solution of the problem which is calculated in the form of a rapid convergent series; some definitions and theorems are reviewed as a basis in solving fuzzy differential equations. An example is applied to illustrate the proposed technical accuracy. Also, a comparison between the obtained results is made, in addition to the application of the crisp solution, when the-level equals one.

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Publication Date
Wed Jan 01 2020
Journal Name
Advances In Intelligent Systems And Computing
Forecasting by Using the Optimal Time Series Method
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Scopus (15)
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Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Optimized Artificial Neural network models to time series
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        Artificial Neural networks (ANN) are powerful and effective tools in time-series applications. The first aim of this paper is to diagnose better and more efficient ANN models (Back Propagation, Radial Basis Function Neural networks (RBF), and Recurrent neural networks) in solving the linear and nonlinear time-series behavior. The second aim is dealing with finding accurate estimators as the convergence sometimes is stack in the local minima. It is one of the problems that can bias the test of the robustness of the ANN in time series forecasting. To determine the best or the optimal ANN models, forecast Skill (SS) employed to measure the efficiency of the performance of ANN models. The mean square error and

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