Biophysical properties of PPF/HA nanocomposites reinforced with natural bone powder

Kamel, Nagwa A.,Mansour, Samia H.,Abd-El-Messieh, Salwa L.,Khalil, Wafaa A.,Abd-El Nour, Kamal N. Techno-Press 2015 Advances in materials research Vol.4 No.3

Biodegredable and injectable nanocomposites based on polypropylene fumarate (PPF) as unsaturated polyester were prepared. The investigated polyester was crosslinked with three different monomers namely N-vinyl pyrrolidone (NVP), methyl methacrylate (MMA) and a mixture of NVP and MMA (1:1 weight ratio) and was filled with 45 wt% of hydroxyapatite (HA) incorporated with different concentrations of chemically treated natural bone powder (NBP) (5, 10 and 15 wt%) in order to be used in treatment of orthopedics bone diseases and fractures. The nanocomposites immersed in the simulated body fluid (SBF) for 30 days, after the period of immersion in-vitro bioactivity of the nanocomposites was studied through Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX) in addition to dielectric measurements. The degradation time of immersed samples and the change in the pH of the SBF were studied during the period of immersion.

Expert System Shells for Rapid Clinical Decision Support Module Development: An ESTA Demonstration of a Simple Rule-Based System for the Diagnosis of Vaginal Discharge

Maged N. Kamel Bou 대한의료정보학회 2012 Healthcare Informatics Research Vol.18 No.4

Objectives: This study demonstrates the feasibility of using expert system shells for rapid clinical decision support module development. Methods: A readily available expert system shell was used to build a simple rule-based system for the crude diagnosis of vaginal discharge. Pictures and ‘canned text explanations’ are extensively used throughout the program to enhance its intuitiveness and educational dimension. All the steps involved in developing the system are documented. Results:The system runs under Microsoft Windows and is available as a free download at http://healthcybermap.org/vagdisch.zip (the distribution archive includes both the program’s executable and the commented knowledge base source as a text document). The limitations of the demonstration system, such as the lack of provisions for assessing uncertainty or various degrees of severity of a sign or symptom, are discussed in detail. Ways of improving the system, such as porting it to the Web and packaging it as an app for smartphones and tablets, are also presented. Conclusions: An easy-to-use expert system shell enables clinicians to rapidly become their own ‘knowledge engineers’ and develop concise evidence-based decision support modules of simple to moderate complexity, targeting clinical practitioners, medical and nursing students, as well as patients, their lay carers and the general public (where appropriate). In the spirit of the social Web, it is hoped that an online repository can be created to peer review, share and re-use knowledge base modules covering various clinical problems and algorithms, as a service to the clinical community.

Study of leaching of a 2M-Zirconolite (Ca0,83Ce0,17ZrTi1,66Al0.34O7) in acidic and basic media

R. Souag,N. Kamel,M. Hammadi,Z. Kamel,D. Moudir,F. Aouchiche,Y. Mouheb,S. Kamariz 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.1

Zirconolite is a mineral intended for actinides elements confinement and is known for its good chemical durability. In this work, 2M-zirconolite, with the chemical formula: Ca0,83Ce0,17ZrTi1,66Al0.34O7 have been synthesized at 1400 o C by the metallurgical route at a laboratory scale. This stoechiometry corresponds to a CeO2 loading of 8.61 m.%. Ce is employed as an actinide surrogate. The effect of both pH and temperature on the chemical durability of this mineral has been studied. Phase identification and micrography observations have been done by X-ray diffraction, scanning electronic microscopy, and Fourrier transform infra-red spectroscopy. The end-product has a monophasic structure of 2M-zirconolite. Its density is about 4.013 g/cm3 , and its relative density is of 96 %TD. It has a microhardeness of 370 MPa. The Ce behavior in leaching media of extreme pH values: acidic medium (pH = 2) and basic medium (pH = 12), at 23 o C and 70 o C, shows that the Ce dissolution speeds are faster at 70 o C compared with those obtained at 23 o C. The 2M-zirconolite matrice presently studied appears to have a good chemical durability.

Analysis of Dam Behavior by Statistical Models: Application of The Random Forest Approach

Ahmed Belmokre,Mustapha Kamel Mihoubi,David Santillán 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.11

Dams are singular infrastructures whose safety assessment requires mathematical models for predicting its behavior and detecting anomalies. Here, we develop an approach based on random forest regression for dam displacement prediction. Random forest regression is a non-parametric statistical technique that can deal with non-linearities and does not need assumptions regarding relationship between predictors. Inputs to the model are the water level in the reservoir, time, and concrete temperature, and the outputs –predicted variables– are movements at the desired points. Since concrete temperature is only available at those points where thermometers are placed, we compute the thermal field at any point of the dam through a one-dimensional deterministic model. Our thermal model accounts for solar radiation, shading, night and evaporative cooling, convection with the air, and long wave radiation exchange. We assess the performance of our model by comparing its estimates with recorded data at a case study, an arch dam located in Algeria, and with outputs computed by two widely used statistical models and an artificial neural network model. Our model provides satisfactory predictions and improves the results of the other models. Our approach is a powerful tool for analyzing dam displacements and incorporates a rigorous evaluation of thermal loads. It emerges as a good alternative for practitioners and stakeholders.

An investigation on the mortars containing blended cement subjected to elevated temperatures using Artificial Neural Network (ANN) models

A.A. Ramezanianpour,M.E. Kamel,E. Ghiasvand,H. Shokrani,N. Bakhshi,A. Kazemian 사단법인 한국계산역학회 2012 Computers and Concrete, An International Journal Vol.10 No.6

This paper presents the results of an investigation on the compressive strength and weight loss of mortars containing three types of fillers as cement replacements; Limestone Filler (LF), Silica Fume (SF) and Trass (TR), subjected to elevated temperatures including 400oC, 600oC, 800oC and 1000oC. Results indicate that addition of TR to blended cements, compared to SF addition, leads to higher compressive strength and lower weight loss at elevated temperatures. In order to model the influence of the different parameters on the compressive strength and the weight loss of specimens, artificial neural networks (ANNs) were adopted. Different diagrams were plotted based on the predictions of the most accurate networks to study the effects of temperature, different fillers and cement content on the target properties. In addition to the impressive RMSE and R2 values of the best networks, the data used as the input for the prediction plots were chosen within the range of the data introduced to the networks in the training phase. Therefore, the prediction plots could be considered reliable to perform the parametric study.

Heat transfer analysis of Carreau–Yasuda nanofluid flow with variable thermal conductivity and quadratic convection

Akbar Asia Ali,Awan Aziz Ullah,Nadeem Sohail,Ahammad N Ameer,Raza Nauman,Oreijah Mowffaq,Guedri Kamel,Allahyani Seham Ayesh 한국CDE학회 2024 Journal of computational design and engineering Vol.11 No.1

Brownian motions and Thermophoresis are primary sources of nanoparticle diffusion in nanofluids, having substantial implications for the thermo-physical characteristics of nanofluids. With such a high need, the 2D, laminar MHD (Magnetohydrodynamic) quadratic convective stream of Carreau–Yasuda nano liquid across the stretchy sheet has been reported. The flow is caused by surface stretching. The principal purpose of this extensive study is to enhance thermal transmission. The effects of variable thermal conductivity and heat source are considered as well. The governing boundary layer equations are transmuted using similarity parameters into a series of non-linear ODEs (ordinary differential equations). The bvp4c algorithm is adopted to fix the translated system numerically. The effects of prominent similarity variables over the temperature, velocity and concentration field are graphically visualized and verified via tables. It explored that fluid’s speed diminishes for the more significant inputs of the magnetic coefficient, Brownian motion coefficient and Prandtl number. The thermal efficiency is improved for larger values of thermophoretic constant, varying thermal conductance and heat-generating parameters. The concentration field has proved to be a decreasing function of nanofluid constants.