Jamal Abdul-Nasser is a major trunk road that divides Sebha city into two semi-equal parts. It connects almost all districts with different activities and services in the center of the city. Alongside Jamal Abdul-Nasser Street, exist various types of activities: administrative, educational, commercial, public services and some other activities. Due to its importance, the street carries out the densest traffic movement within the city. This paper tries to study and analyze traffic movement at five intersections on Jamal Abdul-Nasser Street: (1) Al-Nahdha; (2) Khaled IbnAl-Walid; (3) Al-Khotoot; (4) Al-Tijari Bank; (5) Al-Zeraie Bank. Selection of the pre-mentioned intersections referred to their importance as converging points to various important activities and land uses. Data required for the study purposes include intersection characteristics, traffic flow characteristics and traffic composition pattern. The results reveal the significance of taking care of the geometric and regulatory aspects that enable the intersections to perform well with regard the smoothness of traffic flow.

Isothermal transformation characteristics of a medium carbon Ti-V microalloyed steel were

investigated using light microscopy, scanning electron microscopy (SEM) equipped with energy

dispersive spectroscopy (EDS), and by uniaxial compressive testing. Samples austenitized on 1100 C

were isothermally treated in the range from 350 to 600 C and subsequently water quenched. The

final microstructure of the samples held at 350 C consisted of bainitic sheaves and had compressive

yield strength, approximately from 1000 MPa, which is attributed to high dislocation density of

low bainite. At 400 and 450 C, acicular ferrite became prevalent in the microstructure. It was also

formed by a displacive mechanism, but the dislocation density was lower, leading to a decrease of

compressive yield strength to approximately 700 MPa. The microstructure after the heat treatment at

500 C consisted of coarse non-polygonal ferrite grains separated by pearlite colonies, principally

dislocation free grains, so that the compressive YS reached a minimum value of about 700 MPa. The

microstructure of the samples heat-treated at 550 and 600 C consisted of pearlite and both grain

boundary and intragranular ferrite, alongside with some martensite. After 600 s, austenite became

stable and transformed to martensite after water quenching. Therefore, the presence of martensite

increased the compressive YS to approx. 800 MPa.

This work is focused on nucleation stages during isothermal austenite decomposition in two medium carbon Vanadium Ti / Ti free micro alloyed steels. Isothermal treatment was carried out in the temperature range 350 to 600οC. Metallographic evaluation using optical and scanning electron microscopy (SEM) enabled determination of the nucleation onset phases of isothermally decomposed austenite. Mainly three phases are found to be relevant to this initiation stage of transformation: first is related to grain boundary nucleated ferrite (GBF), second is related to intra-granularly nucleated ferrite (IGF) and the third to pearlite (P). GBF and IGF are divided into the high temperature and the low temperature segments as consequence of either displacive or diffusion nature of transformation. Addition of titanium to V – micro alloyed steel in this work seems to be balanced by a slightly higher C and Mn content, leading to limited effect on nucleation stage of austenite decomposition. The results show that during continuous cooling, onset of pearlite phase can take place. It occurs at temperatures ≥ 500 C°, followed by an incomplete reaction phenomenon. The main characteristics of pearlite is always nucleated on the surface between proeutectoid ferrite and austenite. Incubation time for onset of pearlite decrease with decrease of temperature.

This paper aims to demonstrate the application of two different control techniques, namely the Linear Quadratic Regulator (LQR) and a neural network-based controller to evaluate and control the vibrations that occurred in the car's suspension system. When the car suspension is designed, a quarter car model with 1-DOF is used. A complete control system is needed to provide the desired suspension performance and characteristics such as passenger comfort, road handling, and suspension deflection, this control system performed by using the Matlab software and includes three parts: input signals (actuator force and road profile), Controller, and the suspension system model. The simulation results show a comparison between the uncontrolled suspension system and the suspension system with a neural network-based controller and the active suspension system of the car based on the linear-quadratic regulator, and it is explained thoroughly.

Vehicle safety and control is attracting attention increasingly in an attempt to improve the stability and manoeuvrability of vehicles. Three degrees of freedom vehicle dynamic model (called planar vehicle model) is established. Based on theories of fuzzy PID control and neural network based-Controller, controller of vehicle stability is designed by using the method of direct yaw rate control and the two different control strategies. The controllers were compared under one road condition which is a lane change of manoeuvre. By comparing and analyzing the control effect of fuzzy PID control and neural network based-Controller, the result shows as follows: the two controllers improved the yaw rate to follow the reference yaw rate but, using the fuzzy PID controller gave a better and closer path for the desired path of yaw rate compared to using of the neural network controller.

In this paper, a series of experiments were conducted including testing of the capabilities of composite material as an energy absorber. Composite plate specimens with different corrugation profile have been fabricated and tested under the same condition. The corrugated profiles are: sinusoidal, triangle, and square shape. All these specimens were made of glass fibers using hand layup technique. The corrugated plates are subjected to quasi-static compression load. In addition to that same kind of tested specimens have been modeled and tested using Finite Element Method (FEM). Theoretical and experimental results in a form of energy absorption and specific energy have been recorded. It is found that results of theoretical and experimental tests are almost exactly identical. It has been observed that composite plate with square profile recorded the highest energy absorption and specific energy for theoretical as well as experimental tests.

This paper is devoted to study the effect of crashing of vehicles with concrete blocks that placed around lighting poles. Unexpected dangers takes place if crashing occurs. It may cause death of the driver and passengers, or severe injuries. In order to minimize or eliminate this risk, a system made of corrugated composite material plates have been designed to replace the concrete blocks around lighting poles. This system is made of reinforced fiber glass and it is modeled to crash with a model of car exactly similar to the real one, forming a simulation of car accident. Modeling process takes place using Finite Element Analysis (FEA). ANSYS software utilized for this purpose. Simulation was performed at three different speeds of the vehicle. Results obtained have been recorded in a form of deformed mesh, and contours. The results proved that the new designed system is working perfectly and it has the ability to absorb impact energy caused by car accident. Therefore, by using composite material instead of concrete, risk of death and injuries will minimized or completely eliminated.

Currently, ionic liquids (ILs) have apprehended considerable attention as greener substitutions to volatile organic compounds. In this work, duplicate 1-methyl-2-(butyl-4-sulfonate) pyrazolium hydrogensulfate (MSBPHSO₄) were synthesized by two different methods. It is observed that IL2 is significantly less stable and more viscous than IL1. To assess their catalytic actions, each IL was explored individually for in-situ transesterifying of Ricinus Communis seeds. Under similar reaction conditions, the percentage of methyl esters obtained from in-situ transesterification catalyzed by IL1 and IL2 were 88.5 and 76%, respectively. Hence, the use of IL free halide has the opportunity to achieve high esters content. At investigated optimal conditions with increasing the temperatures beyond 120 °C, in contrast to IL1, IL2 led to significant drop in the product yields. This phenomenon means that higher temperatures offer greater …