Proposed Equation to Estimate the Total Dissolved Salts in Sand

ان الهدف الرئيسي من هذه البحث هو اشتقاق معادلة جديدة والتي يمكن استخدامها للحصول على الأملاح الكلية الذائبة في الرمل. هذه المعادلة تمكننا من الحصول على الأملاح الذائبة الكلية من خلال إيجاد كثافة المحلول المائي الناتج عن حل اي نموذج في الماء المقطر. هذه المعادلة تظهر نتائج جيدة جدا، لذلك تم اقتراح طريقة جديدة في هذا البحثلايجاد الأملاح الذائبة الكلية من خلال تطبيق هذه المعادلة التي تم اشتقاقها في هذا البحث دون الحاجة إلى استخدام الأساليب المعتادة لايجاد تلك الأملاح الذائبة.  في هذه الدراسة يستخدم الأسلوب المقترح اختلاف الكثافة بين الماء المقطر والمحلول المائي الذي يتم الحصول عليه من حل نموذج الرمل بالماء المقطر. الطريقة المقترحة هذه جعلت اختبار الأملاح الذائبة أكثر سهولة وسرعة عند تطبيقها. الطريقة المقترحة تساوي أو تتجاوز في دقتها طرق الاختبار الأخرى.The major objective of this paper is pediment a new equation which can be used to obtain the total dissolved salts in the sand. This equation enables us to obtain the total dissolved salts by finding density of the watery solution resulting from dissolve any sample in distilled water. This equation shows very good results, so in this paper a new method is proposed to find the total dissolved salts by applying this equation which derived in this research without the need to use usual methods in finding those total dissolved salts. In this study, the proposed method uses the density variation between distilled water and the watery solution which is taken from the sand sample dissolved with distilled water. This proposed method will make the test of total dissolved salts more easily and quickly applied. The proposed method is equal or exceed in its reliability on other testing methods

Numerical Analysis of Contact Area under Slippage Conditions

في هذا البحث، تم دراسة منطقة التماس التي تتولد بين جسمين (أحدهما سطح مستو والاخر سطح نصف أسطواني) تحت تأثير الانزلاق، حيث أنها تمثل واحدة من المشاكل الهامة في الهندسة الميكانيكية وخاصة في تصميم الروبوتات. تم دراسة العديد من المعاملات مثل قوى الاحتكاك، الاجهادات المكافئة، معامل الاحتكاك، وتشوه منطقة التماس. حيث تم رصد سلوك هذه العوامل خلال الانزلاق الذي يتم إنشاؤه بين سطح مستو مصنوع من سبائك الحديد الصلب والجزء الآخر المصنوع من المطاط. أظهرت نتائج المحاكاة سلوكا هاماً، وخاصة في بداية الانزلاق وظاهرة (الالتصاق-الانزلاق) بمعنى آخر، مخرجات المحاكاة تشير إلى أن تأثير الانزلاق له سلوك هام، خاصة عندما تبدأ كل من ظاهرة الانزلاق والالتصاق بالحدوث. وتهدف هذه التحليلات إلى فهم كيفية تأثر منطقة التماس لتصميم ما يمنع حدوث الانزلاق والضرر في الاجزاء الهندسية المتماسة. In the present paper, the contact of area, which is produced between a pair of bodies (flat surface and hemi-cylindrical shape), has been studied under the effect of slippage occurrence, where it represents one of the important problems in the mechanical engineering, especially in robotic design. Many parameters have been studied, like frictional forces, equivalent stresses, friction coefficient, and contact area of deformation. The behavior of these parameters has been monitored during the slippage that is generated between the flat surface made from cast alloy steel and the other part made from rubber. The finite element method (FEM) with SOLIDWORKS software was used to simulate this contact area under the slippage effect. The results of the simulation showed a significant behavior, particularly at the beginning of slippage and the stage of (stick-slip) phenomena, in other words, the simulation outputs indicated that the slippage influence has an important behavior, especially when the phenomena of both slippage and stick-slip stage start to occur. These analyses are intended to understand how the contact area affected to design measures to prevent the slippage occurrence and the damage in contacted bodies

Parametric Analysis of Surface Roughness and Metal Removal Rate during Electrical Discharge Machining of O1 Tool Steel

This work studies the impact of input machining parameters of Electrical Discharge Machining (EDM) on the machining process performance. Tool steel O1 was selected as the workpiece material, copper as the electrode material, and kerosene as the dielectric medium. Experimental runs have been carried out with a Design of Experiment (DOE) technique. Twenty tests are accomplished with the current range of (18 to 24 Ampere), a pulse duration range of (150 to 200 µs), and a pulse-off time range of (25 to 75 µs). Based upon the experimental study's output results, the EDM parameter's effect (voltage of power supply, discharge current, pulse duration, and pulse pause interval) on the responses of the process represented by surface roughness value Ra and Metal Removal MR rate.  The results obtained by the DOE approach are analyzed by STATISTICA software. It has been concluded that an increase in the current and pulse duration maximizes both metal removal rate and surface roughness. At the same time, they are minimized by maximizing the pulse pause interval

Grasping Force Prediction for Underactuated Multi-Fingered Hand by Using Artificial Neural Network

In this paper, the feedforward neural network with Levenberg-Marquardt backpropagation training algorithm is used to predict the grasping forces according to the multisensory signals as training samples for specific design of underactuated multifingered hand to avoid the complexity of calculating the inverse kinematics which is appeared through the dynamic modeling of the robotic hand and preparing this network to be used as part of a control system.Keywords: Grasping force, underactuated, prediction, Neural networ

Coupled modelling of naturally occurring radionuclides in a cementitious engineered barrier

Constructing a robust numerical model that captures multi-mineral transformations, multiple chemical reactions, and secondary phase pathways in geological repositories is challenging due to uncertainties in parameters and a limited available database describing the kinetics of dissolution/precipitation reactions. In this work, combined with experiments, a comprehensive reactive transport model is used to study the chemical and physical interactions among radionuclides, cement leachate and the host rock in a nuclear waste repository. Hence, the modelling efforts will enhance the understanding of the transport of radionuclides in complex soil/rock systems and highlight the critical factors driving their migration in soils/rocks. To achieve these aims, the modelling of the radionuclide migration process was first investigated, considering all possible reactions that could take place. Then, the PHREEQC software was used for the numerical simulation, and experimental data were used to validate the model. The experiment studied a system for 15 months and 15 years with young cement leachate (pH=13) and intermediate cement leachate (pH = 10.8), respectively. Then, with the dissolution/precipitation kinetics implemented and verified, the transport process was incorporated with the aim of building a geochemical model that will describe the multimineral mass transfer under different conditions. Furthermore, the geochemical model was constructed to ensure the porosity evolution of the porous medium. Finally, radionuclide migration was incorporated into the model to characterise the effect of the sorption process. These studies showed that fluid chemistry controls the dissolution/precipitation of the primary minerals, which will control the long-term chemical equilibria and mineralogical composition of the host rock impacted by the alkaline leachate. Meanwhile, the chemical interaction between hyper-alkaline leachate and the host rock results in a series of mineralogical reactions, including cycles of minerals dissolution and precipitation (calcium silicate hydrate gel, C-S-H phases, C-A-S-H phases, hydrated silicate, and Na-Ca zeolites). Furthermore, by coupling the mineral volume changes and porosity evolution to the dissolution/precipitation reaction model, the results showed a better fit in ion concentration compared to the fixed porosity model, as it led to a more reactive surface area with the cement leachate. Moreover, the model shows that the dissolution of primary minerals in the host rock is the initial driving mechanism for the chemical evolution of the system. At the same time, the subsequent precipitation of several secondary phases controls the host rock's long-term chemical equilibria and mineralogical composition. Lastly, the sorption of uranyl (UO2_2+ (U_VI)) was found to strongly depend on the surface complexation model assumed, with no significant removal of U_VI by precipitation or ion exchange process. Furthermore, uranyl adsorption by the C-S-H phase was found to be minimum, which could be related to the lack of surface complexation parameters for C-S-H minerals

Synthesis, Characterization and Thermal Behavior of Four Arms Poly(L-lactide) via Ring Opening Polymerization

Four (4-arms, polyL-Lactide) were prepared by having different repeating units (10, 25, 50 and 100) from Erythritols and L-Lactide. The polymers were characterized by several methods as FT-IR, 1HNMR, 13CNMR, Gel Permission Chromatography and Scanning Electron Microscopy and finally their thermal stability was evaluated. The all characterization methods were confirmed the expected structure of prepared polymers, on the other hand the prepared polymers have a thermal stabilizing above 175° C, therefore, it is expected to be suitable for use in tissue engineering and drug release applications.   Keywords: poly L-Lactide, four arms, ring-opening polymerization, thermal behavior.

A Study of Delay and Data Traffic of IEEE 802.15.4 ZigBee-Based WSN in a Smart Home

Wireless sensor networks (WSN) play a key role in modern applications, for instance, in smart homes as will be demonstrated in this paper. ZigBee technology provides better support when compared with WiFi, Bluetooth and Ultra Wide Band (UWB) standards regarding transmission range. This paper deals with the use of ZigBee WSN in a domestic application, namely smart home control. This model comprises a smart home with multiple rooms, designed in such a way that each room has sensors comprise for a varied environment. The sensor nodes will be presented by ZigBee end device which transmits the traffic to a master node in the form of a ZigBee coordinator. An OPNET modeler V14.5 was used in this simulation study. This paper presents seven models related to delay and data traffic received to improve WSN performance. Seven different WSN designs variations were utilized according to the number of rooms, sensors, coordinators, and routers. The outcomes demonstrate that one coordinator model causes more delay when compared with multiple coordinator models. Conversely, the presence of a router causes additional delay. This model should help electrical engineers when designing smart homes that utilize WSNs

INVESTIGATION OF SURFACE ROUGHNESS IN MODERN FINISHING PROCESS USING PERMANENT MAGNET

This work introduces an investigation of the surface roughness (Ra) during flat plate machining utilizing magnetic abrasive finishing process (MAF). In this study three parameters (Machining time, Mesh size, and Gap) were studied. The MAF tool is made from permanent magnet and the abrasive powder is consisting of 40% of SiC and 60% Fe powder with three Mesh size (100, 250, and 400 µm). The Taguchi L9 array was used in designing the experiments. The results show that the increasing machining time caused a decrease in Ra. The increase in mesh size and the gap will increase the surface roughness. The dominant factor that affect the surface roughness was the machining time due to enough time to machine the target surface

Evaluation of Properties of Roller Compacted Concrete

The experimental and analytical behavior ofvarious mixes of roller compacted concrete (RCC) using different materials is presented in this work. This work is divided into two groups of experiments. In the first group a reference mix was prepared using local materials (cement, sand, aggregate). Mechanical and dynamic properties of reference mix with and without admixtures have been obtained. Also, this series includes a study of the various variables affecting the mechanical anddynamic properties of RCC. In this work, the effect of cement content, water/cement W/C ratio and type of aggregate on the mechanical properties has been studied. The optimum mixes which have good properties obtained from the first group of study were used in the second group. In this work, the effect of admixtures and type of admixtures (steel filings, metakaolin, fly ash, lime, rice husk and concrete wastes) on the mechanical properties has been studied. The analysis of results showed that using steel filings improves the mechanical properties when replacing the sand by steel filings in (5, 10, 15 and 20) % by weight. The ultimate compressive strength at 7 and 28 days is higher by 13.2 and 24.7%, respectively, than the compressive strength using sand only. Partial cement replacement by mineral admixtures like metakaolin with (10, 20 and 30) %, lime with (4, 6, 8, 10, 20 and 30) %, fly ash with (10, 20 and 30) % and rice husk with (4 and 8) % decreases the strength and other properties at early age of 28 days by about 12.02% when using metakaolin by 20% and about 12.5% when using lime by 10

Fusion for Multiple Light Sources in Texture Mapping Object

Abstract—In this paper, fusion method using wavelet transform was used to calculate the effects of multiple sources of light to make the object look more realistic and more informative than the original parts which take the effect of each light source alone. The color value of any pixel in the object depends essentially on the color of the specific mapped texture as well as on the effect of the light sources that produce bright or dark pixels value depending on the distance between the pixel and light source and the direction of light rays. The proposed method merges the effect of multiple lights. Instead of summing these effects, the method takes from each pixel one of three conditions. These states are the maximum effect among all sources of the light, the minimum effect among all sources to reflect fine shadow and the ratio effect from all sources. This ratio depends on the relative parameters among all sources