The influence of vanadium and nitrogen on microstructure and mechanical properties of medium-carbon

steels has been studied by means of metallography and mechanical testing. Vanadium addition to the low

nitrogen steel suppresses the formation of ferrite–pearlite following the low reheating temperatures and microstructure

consists of bainitic sheaves. Increasing nitrogen at the same vanadium level promotes the acicular

ferrite formation. For high reheating temperatures, dominantly acicular ferrite structure in both the low

nitrogen and the high nitrogen vanadium steels is obtained. The results suggest that vanadium in solid solution

promotes the formation of bainite. The effect of nitrogen is related to the precipitation of VN particles in

austenite with high potency for intragranular nucleation of acicular ferrite and to the precipitation of V(C, N)

particles in ferrite with high potency for precipitation strengthening. Addition of both vanadium and nitrogen

considerably increases the strength level, while CVN20 impact energy increases on changing the microstructure

from bainitic ferrite to the fine ferrite–pearlite and acicular ferrite.

The title complex was isolated as red solid material from the reaction of Co(SCN)2 with 4(Salicylaldimine) antipyrine in ethanol. The molecular structure has been determined by elemental analysis, FT IR, UV-Vis and X-ray diffraction. The crystallographic data are: monoclinic

P21/n, a = 9.8335(3) A, b = 18.8593(6) A, c = 11.2921(4) A, = 90', =  = 90', V = 2041.46(12) ų and Z 2, R =0.045. The dicobalt (Il) complex is centrosymmetric dimer in which the Co(ll) ions are six coordinate being bonded to three coordinating donor sites from the corresponding tridentate Schiff base ligand and the fourth one is relatively bonded by phenolic oxygen, the fifth and sixth donor sites comes from isothiocyanate and methanol.

The rapid growth of advanced robots has given researchers unprecedented opportunities to explore and discover new fields of research where robots can be used to assist humans in their daily life. There are many applications that use robots and automation in different aspects of life such as industry, medical, domestic machines and etc. In this paper, the work has been devoted for the use of robotics and robots in cleaning process. The window cleaning robot is one of the robots that have emerged in recent decay. This robot can be used in homes, offices and large buildings. The main target is to design a robot that can clean glass windows efficiently and rapidly even in dangerous and hazardous places. The robot will be controlled using the Programmable Logic Controller PLC. The motion will generated by three servo motors.

The influence of vanadium and nitrogen on microstructure and mechanical properties of

medium-carbon steels has been studied by means of metallography and mechanical testing.

Vanadium addition to the low nitrogen steel suppresses the formation of ferrite-pearlite following

the low reheating temperatures and microstructure consists of bainitic sheaves. Increasing nitrogen

at the same vanadium level promotes the acicular ferrite formation. For high reheating temperatures,

dominantly acicular ferrite structure in both the low nitrogen and the high nitrogen vanadium steels

is obtained. The results suggest that vanadium in solid solution promotes the formation of bainite,

whereas the effect of nitrogen is related to the precipitation of VN particles in austenite with high

potency for intragranular nucleation of acicular ferrite and to the precipitation of V(C,N) particles in

ferrite with high potency for precipitation strengthening. Addition of both vanadium and nitrogen

considerably increases the strength level, while CVN20 impact energy increases on changing the

microstructure from bainitic ferrite to the fine ferrite-pearlite and acicular ferrite.

Differences in activation between spores from strains of Bacillus thuringiensis subsp. israelensis with and without the toxin-encoding plasmid pBtoxis are demonstrated. Following alkaline activation, the strain bearing pBtoxis shows a significantly greater germination rate. Expression of just three genes constituting a previously identified, putative ger operon from this plasmid is sufficient to produce the same phenotype and characterizes this operon as a genetic determinant of alkaline activation.

Adaptive control systems have been studied for many years. There are many types of adaptive control algorithms, one of which is the reference model technique. In this paper, the work has been devoted for the use of model reference adaptive control system (MRAC). The MRAC algorithm with parameters adaptation was developed and applied for control of the DC motor drive. The algorithm is based on the gradient technique with parameter adaptation. The controller can significantly improve system behavior and force the system to follow the reference model and minimize the error between the model and plant output.

In this paper a data compression technique using double transforms is proposed. The compression ability of any transform or a combination of transforms is evaluated by the error in the reconstructed data and/or its fast implementation. This investigation concerns the reduction in the computational requirements for data compression without increasing, significantly, the error in reconstruction. The double transform approach is based on the transformation of input data using WHT, rejecting some of the spectral components, converting the spectrum from WHT domain into DCT domain, and then inverse transform using DCT. In the experimental part of this paper, several contours extracted from 2D images, using the FCCE method for contour extraction, ware used. It is shown that the proposed technique reduces the number of multiplication operations, comparing with DCT. In addition, the compression process does not require any multiplications at the transmitting end, thus can be used for real time compression applications.

We present a model of web-based learning for teaching Visual Programming in Delphi, by adopting individual learning styles. A software system was developed for this purpose where two learning models (namely; 4MAT system and PBL system) are implemented. The goal of this research is to examine the influence of the two selected models on students of different learning styles enrolled in a web-based programming course.

Students were randomly divided into two groups, one for each learning model, and are given access to a website designed specifically for this purpose. Pre and post-tests were carried out.

A controlled evaluation is currently underway to assess the impacts of the system on students programming skills as well as their attitudes surrounding the use of available web facilities.