Al-Qadisiyah Journal for Engineering Sciences

In this research the effect of the reinforcement by fibers on Mechanical properties of polystyrene resin reinforced by aramid fibers was studied .The properties included impact strength , tensile strength Where the Mechanical properties were extracted for polystyrene resin before reinforcement by fibers, then we reinforced the resin by different weight percentage from aramid fibers (%15,%30, %45, %60)and studied the effect on the above mechanical properties. An Improvement was happened in these properties after reinforcement by fibers The value of mechanical properties will increase with increasing percentage of reinforcement . Impact strength increased from(8Kj/m2) to (160Kj/m2) and compressive strength from (37Mpa) to (328Mpa) for reinforcing percentages 0% and 70% respectively .

The effect of intermediate annealing treatment on the micro-hardness and corrosion resistance for Nickel – Chromium (3.2%Ni-1.57%Cr) alloy steel was carried out in this investigation, specimens from this steel were prepared and carburized, hardened and tempered, and intermediate annealing process was added at different temperature (750,770, and7900C)to achieve a structure of ferrite (α-Fe) and austenite(γ-Fe) phases by heating and then dual-phase structure by quenching in oil and at different times (45, 60, and75 min) to uniform the distribution of carbon in this alloy steel before hardening process.
The loss of weight method was used as a function to measure the corrosion resistance for Nickel - Chromium alloy steel after embedded in (3.5%NaCl ) solution as an aggressive media for different holding times (2, 4,5,8 and 10 Days) .
It was found that was an increase or decrease in the hardness depending on the temperature of the intermediate annealing treatment and its holding time.
The study also showed an increase in the corrosion resistance mainly due to the temperature of the intermediate annealing treatment and decrease when the holding time increase .
The experimental results showed that the best micro-hardness value was found at(7500C) intermediate annealing temperature for (58min) holding time and the best corrosion resistance was a chivied at (7900C) with( 45 min ) holding time and (2Day) embedded time .

There are a lot of admixtures with different uses in the construction industry but it is not easy to choose the suitable admixture.
The (conplast Wp100), (sika grout 214) with (2%, 4%, 6%) and (5%, 15%, 30%) respectively have been used by weight and subistution of cement to the concrete mixture using (10) mm maximum size of coarse aggregate.
The results showed increasing in (compressive, strength, splitting tensile strength, dry density) and reduction in absorption by (29.4%, 21.5%, 18.3%) and (37.2%) respectively for (28) days test compared with the reference concrete mixture.

This study is mainly concerned with legibility in urban environment in an attempt to find the kind of the relationship between changing the structural propertires for the space discipline in legibility of the mind picture for the witness and indicating the significant.
Lastly, planning for historical cities in Iraq is aimlessly done and it lacks the scientific fundamentals.
The problem of the study is that there is no cognitive vision which clarifies the relation between changing the structural properties for the space discipline in legibility in urban environment receiver according to the hypotheses of the research and to achieve its aim, the researcher was adopted two scientific ways: the first one the structural method- through using of arithmetical way in indicating numerical weighs for space structure .The weighs express the relative for the structural parts. The second one: the perceptional method: by using questionnaire to know the mind picture for the receiver which results from the difference of the legibility degree in urban environment and indicating the place of indicator points in the city. For the purpose of the research and to achieve and treat the research problem in accordance with the aims of the research , the researcher, chose AL-Kefil City as a historical city as a sample of the study for its importance from the historical point of view to reach up some conclusions and recommendations.

This search presents the development and application of an Expert System for operating Haditha dam, which is considered the second biggest dam in Iraq. Haditha dam is a multi – purpose hydro – development designed to control the Euphrates River flow in the interests of irrigation, electric power generation and for partial accumulation of extreme Euphrates River inflows into Haditha reservoir.
Haditha dam was constructed on the Euphrates River in the Middle West of Iraq (8km) upstream from Haditha town. In 1988 the project was completed. Central and southern parts of Iraq get the benefit of irrigation water from its reservoir. It is consist of the body of the dam, hydro-power station generates (660 Mw) from (6 generator units), Spillway with (6 opening controlled by radial gates) and two Bottom outlets.
Ministry of Water Resources denoted that year (2009) is a drought year for that reason the good management for water resources is very important. Haditha dam was taken as case study because the important of the project and its [water level elevation became (116 m.a.s.l.) for the mentioned year while its dead water level is (112 m.a.s.l.),(G.S.D.R.),(2012)] which means that the reservoir is almost empty, where the hydro-power station is stopped for (4 months) (from 9/2009 to 12/2009) and the release was just from the Bottom outlets. Therefor an Expert System is developed to operate the dam. Expert System (ES) is a branch of artificial intelligence (AI) that has achieved considerable success in recent years. The area of expert systems involves investigation into methods and techniques for constructing human-machine systems with specialized problem solving expertise. Expert system has many applications in the field of water engineering such as construction, design, planning, operation and maintenance of hydraulic structures. The language used to program the Expert System in this search is (VISUAL BASIC) program within windows environment. The Expert System has developed depending on actual data for operating dam for (21 years) from 1991 to 2011),[G.S.D.R.,(2012) ]. It is found that using the developed Expert System for operating Haditha dam monthly and daily was very efficient where randomly the measured average monthly water levels for (10/1991) and (9/2011) were (136.95 and 135.72, respectively) while the calculated by the program (136.80 and 135.59, respectively) were the results calculated showed that the difference between the calculated water levels and the measured water levels was as average (15 cm) which means that the development of expert system is correct.

DNA Sequences making up any organism comprise the basic blueprint of that organism so that understanding and analyzing different genes within sequences has become an extremely important task. Biologists are producing huge volumes of DNA sequences every day that makes genome sequence database growing exponentially. The databases such as Gen-Bank represent millions of DNA sequences filling many thousands of gigabytes computer storage capacity. Hence an efficient algorithm to compress DNA sequence is required. In this paper compression algorithm which is called “Huffman code tree” is used to code and compress DNA sequences. Depending upon this algorithm we assigning binary bit codes (0 and 1) for each base (A, T, C, and G). After assigning the bases by bit codes, we determine the code for each base. Code for each base is determined by tracing out the path from the root of the tree to the leaf that represents that base.
Huffman code provides a variable code length. In fact the codes for characters having a higher frequency of occurrence are shorter than those codes for characters having lower frequency. So this algorithm compress DNA sequences better than from old method (fixed length) if we assigning 2 bits per base. From analysis the results, average code length (1.62 bits/base) can be achieved using this algorithm. For a higher compression ratio advised to use other compression method with the proposed method such as the learning automata.

In this research the values of rejected and accepted (programmed) are compared to the variable control systems (VCS) by drawing curves and determine the values of the voltage switching surface system (VSS), which is working under the external effects and connect in the parts of control structure (S1, S2).The analysis presented here in treating the question of changing the structure when a deterministic disturbance acts anywhere in the control system using (Mat lab programs).
An adaptive model reference algorithm in established to make the control system respond satisfactory or not there is a disturbance. In this system best responses are achieve by noting many information and factors like steady state error (S.S.E), order of control system, type of switching and also notes the logarithmic structure for VSS voltages in case of input reference sources model to get best performance.

The effect of tempering heat treatment on corrosion resistance of carbon steel DIN CK45 is investigated. Test specimens (1.5*1.5*0.3) Cm were prepared according to ASTM G71-30 Tempering Heat treatments at 150, 350 ◦ C were performed by heating the specimens in electrical furnace to 850 ◦ C and cooling in water then preheated to 150, 350 ◦ C and cooled in air.
Corrosion tests were investigated by electrochemical potential state cell in prepared salt water (sea water) at multi velocities (1, 2, and 3) m/min where the test specimen represents the positive electrode (anode) pole. Tafel equation was adopted to calculate the corrosion rate. The obtained results show that the heat treatment improves the corrosion resistance by increasing the combination of iron with carbon reducing by that the combination of iron with oxygen which produces rust. On the other hand the increasing of velocity of the media (sea water) contributed in decreasing the corrosion rate because of reducing the assembling of ions on cathode pole.

Bending process is the one important process in the sheet metal forming in many industries, there are many parameters having a large effect on it. Spring- back is considered one of the most important indications to specify the quality of product parts. The objective of the present study is to find the optimum bending parameters to get lowest spring back on aluminum- silicon (Al- Si) alloy by applying the Taguchi method. The basic parameters which were taken into consideration in this work are: punch speed, hold time and the orientation of material in order. Experiments have been conducted by using L9 orthogonal array with three levels for each parameter. The bending process were done on Instron device ,the optimum combination of process parameters has been found through analysis of main effect of spring back value (αs) and Signal-to-Noise S/N ratio, and the significant parameter was identified depending on ANOVA analyses. In the present work to determine the level of importance of spring back parameters, the results show that the significant factor is the orientation of metal followed punch speed and hold time, and the obtained results from the experiments are acceptable for the ranges of forming conditions that have been selected in this case study.

Rutting is recognized to be the major distress mechanism in flexible pavements as a result of increase in tire pressures and axle loads. Rutting is caused by the accumulation of permanent deformation in all or some of the layers in the pavement structure. The accumulation of permanent deformation in the asphalt surfacing layer is now recognized to be the major component of rutting in flexible pavements. This is a consequence of increased tire pressures and axle loads, which subjects the asphalt surfacing layer nearest to the tire-pavement contact area to increased stresses.
This research evaluates information on the permanent deformation characteristics of asphalt-aggregate mixtures, with an emphasis on laboratory test techniques for measuring mixture resistance to permanent deformation.
A comprehensive laboratory study was carried out using aggregate gradation for asphaltic surfacing course according with specification limit of SORB/R9, four percentage of asphalt cement were trialed in order to determine the optimum asphalt content for asphalt mixes, four levels of temperatures to accommodate the influence of temperature conditions and three levels of stresses. Uniaxial creep loading strain chosen as performance test to measure the permanent deformation of asphalt mixes. The results show that the temperature has a significant effect on permanent strain and, therefore, temperatures employed for design are relatively high to reproduce the most unfavorable pavement conditions.

In this experimental work, four different curing methods were applied namely including water, air, water heated-air and water heated –water. The results showed that the highest compressive strengths are attributed to the air cured under room temperature after 20hrs curing in heated water at each age. To verify the effect of insoluble residue on the compressive strength of Portland cement, fine particles sand passing from sieve no. 200 and washing in hydrochloric acid were used as an insoluble residue. The Portland cement was replaced by insoluble residue which varied between (0 -7.0) % by weight. The results showed that the higher percentage of insoluble residue to 8.13% in cement mortar gives the lower the compressive strength by 12% of the control mortar compressive strength at 1 day .Although of this reduction of strength, it was found that the compressive strength was still higher than the limits given by ASTM ,BS and Iraqi standards.