Al-Qadisiyah Journal for Engineering Sciences

This paper presents a technique for a speech recognizer used to control the motion of an intelligent
automated mobile robot. The aim is to interact with the mobile robot using natural and direct
communication techniques. The voice is processed to get proper and safe movement of a mobile robot
and satisfying high recognition rate. Features are extracted from speech signal using Mel Frequency
Cepstral Coefficients (MFCC). To realize feature matching, an efficient Dynamic Time Warping
(DTW)-based speech recognition system is presented which is applicable for isolated words of Arabic
language. The tested words are compared to a trained database using this DTW algorithm. On the other
side, the mobile robot is designed with two servo motors as driving actuators. These actuators are
controlled by L298 motor driver circuit. The control algorithm is programmed and downloaded into a
PIC18F45K22 microcontroller which is interfaced to a USB port of a 10\" notebook computer. The
robot proves a capability of understanding the full meaning of the five Arabic speech commands that
steer it forward, backward, right, left, or stop

This paper presents an experimental investigation of the effect of a superplasticizer admixture on
the mechanical behaviour of expanded clay lightweight concrete containing metakaolin material
and recycled glass aggregate. The optimum dosage of the superplasticizer admixture (type SNF)
was adjusted and used by weight of cement. The short and long-term mechanical properties of
concrete mixes were measured in accordance with the relevant British / EN standards. The obtained
results were compared with the results of control concrete mixes (without superplasticizer).
The results obtained showed that the superplasticizer admixture exhibited a 20% reduction in
content of mixing water. All measured values of unit weight, compressive and splitting tensile
strengths increased when the superplasticizer admixture is used. The concrete mix containing 30%
recycled glass revealed an increase in the mechanical strength compared with the mix of 15%
recycled glass. However, the workability of the superplasticizer concrete mixes was degraded,
reaching 44% reduction in slump value

This paper presents one of the most successful method controllers of 3-phase squirrel-cage IM
motor which is employing V/F method with application of pulse width modulation (PWM), this
dynamic model is implemented using Mat Lab simulation program. The improved techniques of
suggested model presents high performance of improving the starting characteristics (starting
current , starting torque) of the double comparison with single-cage IM using PWM techniques at
constant V/F control. Simulation results refers to the characteristics of double-cage better than
single cage and shows that the satisfy performance and good response of this model.

This study investigates the effect of different compacting pressures on microstructure ,physical and
mechanical properties of NiTi shape memory alloys. The sample were prepared by powder metallurgy
technique. The powder mixture containing 55wt% Ni and 45wt% Ti were mixed for 5hours,compacted at
different pressures (400,600,800 and 900)MPa to cylindrical samples, and sintered in two stages. First
heating the compacted samples at temperature of 500°C for 2 hours and at a temperature of 950°C for 6
hours under vacuum conditions (10-4 torr ) . The XRD test shows that the sample compacted at 800 MPa
are consisting of three phases (NiTi monoclinic phase ,NiTi cubic phase , Ni3Ti hexagonal phase ).From
the results, it was found that compacting pressure has essential effect on; improvement of shape memory
effect properties(1.30-5.60)%, increasing hardness(from80.4to137) and compressive
strength(from127.43to431.04)MPa and decrease porosity percentage(from32to22)%.

Construction labour productivity is a major determinant of success of a construction project. Time and
cost overruns of construction projects are widely attributed to poor productivity of construction labour
force. Though considerable research exists on productivity factors in other countries, very little studies
have addressed productivity issues in Iraq. Brainstorming session and site interview survey was
conducted in Karbala province in Iraq, to identify the productivity and the factors affecting bricklayer
labor productivity. Thirteen influencing factors are utilized for productivity forecasting by artificial
neural network (ANN) model, and they include Age, Experience, Gang health, Gang Number,
Weather, wages, Site condition, Material availability, Wall length, Wall thickness, Wall height, Mortar
type, and Security in site. One ANN prediction model was built for the productivity of bricklayer
labors. It was found that the predict productivity approximately the same as the actual productivity
with a good degree of accuracy of the coefficient of correlation (R=86.28%), and mean square error
(MSE) of (1.32%) after testing the network. The developed ANN model can be used dependably for
estimating production rates of bricklayer for any building construction project by incorporating the
influence of selected factors.

In this study, the objective is to obtain optimal values of CNC turning parameters (cutting speed,
depth of cut and feed rate) which result in an optimal value of surface roughness by machining
aluminum shaft. In this work, Taguchi method was carried out on machining of aluminum ENAC43400 material in dry cutting using CNC turning machine type StarChip 450 equip with carbide
cutting tool type DNMG 332. Surface roughness was measured using the POCKET SURF EMD1500 tester. The results obtained of the surface roughness (Ra) are about (1.14-1.91) μm, and the
best was at cutting speed 250 m/min, feed rate 0.05 mm/rev and depth of cut 0.5 mm which is
refers to the optimum machining parameters.

This paper experimentally investigates the effect of high-temperature fire on the structural behavior of
reinforced concrete hollow columns. Sixteen square (120×120mm) columns were fabricated with
600mm length. The experiment\'s parameters were: the hollow size and the temperature of fire. Twelve
specimens were cast with a hollow cross-section by inserting PVC pipes centrally along their length;
these columns were categorized into three groups depending on the hollow diameters: 25.4, 50.8, and
76. 2mm. The remaining samples were solid and gathered in one group. Each group contained four
samples; three of them were burnt at 300, 500, and 700 oC for one hour, and the fourth one was a
reference not exposed to fire. All columns were tested under an axial compressive loading applied
progressively up to the column’s collapse. The experiment results indicated that the collapse load of
columns, having a same cross-sectional area, decreased with increased the temperature. The decline in
columns’ strength ranged from 20.00% to 68.67% for specimens exposed to 300-700oC temperature,
respectively. Additionally, for columns exposed to the same temperature, the collapse load descended
as the hollow size augmented. A decrease of failure load varied from 21.86% to 65.38% for 25.4
to76.2mm hollow size columns, respectively. Finally, columns\' stiffness reduced with increasing the
temperature and the hollow size.

Using of scrap tires will result in recycle the waste of rubber products and solve the problem of
increasing the prices of mineral fuel. Different blends of scrap tires rubber oil (STRO) and diesel
fuel have been investigated experimentally using diesel engine for performance and emission
products. A blend of 10, 20, 30, 40% and standard diesel fuel have been tested in the diesel engine
and the results showed a good improvement in reducing the pollutants. One of the important
problems facing the mixed with fuel oil is to increase the viscosity and decreasing volatility that
lead to carbon deposition and ring sticking of these types of oils. When blended with diesel,
(STRO) presented lower viscosity, improved volatility, better combustion and less carbon deposit.
NOx emission for the blend of 20% scrap tires rubber oil (STRO 20) was reduced by 40%. An
increase in emission of hydrocarbon by 20% was found at full load. The emissions of carbon
monoxide (CO) from scrap tires rubber oil and its blends were higher except in (STRO 20) blend
that reduced by 15%. The brake thermal efficiency was spotted higher with standard fuel than scrap
tire rubber oil and its blends. The present work showed that the 20% blending ratio is the optimum
blending ratio for scrap tires rubber oil depending on experimental test results. Also, the current
study introduce the waste of rubber products as a good alternative fuel blended with diesel fuel
verify economical and environmental benefits

Nowadays, noise becomes one of the most environmental pollutants. Several adverse effects linked
with exposure to environmental noise. The aim of this study was achieved to evaluate noise level in
some selected area represented by schools and medical centres in Al-Diwaniyah city according to
the international standards. Therefore, noise levels were measured using sound level meters type
(SVAN-955) in 10 places (5 schools and 5 health centres and hospitals) in different areas in the
city. Most of these selected schools and health centres were exposed to noise from road traffic. The
study revealed that equivalent sound level and minimum sound level for the schools (65dBA,
59dBA respectively) exceeded the international standards. The equivalent and minimum noise level
in the health centres were (66dBA, 59.6dBA) also exceeded the WHO, USEPA and European
legislations. Therefore, these results will be of help to planners and policy makers in the City to
combat such this problem and Take the necessary actions to legislate the Iraqi standard for noise
exposure and also to reduce the impact of noise on the buildings and common places

The included search casting twenty one concrete mixes, that proportion are (1:1.5:3), (1:2:4) and
(1:3:6). Nine of them with out using plasticizer with three (w/c) (0.50, 0.57, 0.60) as showing at
table (6).And twelve mixes contained a proportion of additive mixture of metal Gelenium No.(5)
with four ratios of Gelenium as shown at table (5) and every mix has (w/c) (0.45:0.53:0.60).
- Soft conceret of non container plastizer tested by workablity (slump test). The mex (1:1.5:3)
gave best result (60mm) , least mix (1:2:4) gave (40mm), least mix(1:3:6) gave (25mm)
according to reference mixture.
- Soft conceret with Gelenium ratio plastizer gave best slump for Nine mixs with three (w/c)
ratio (40%, 45%, 50%) And Gelenium (3%) , the best result for mix(1:1.5:3) equal
(98mm),least mix (1:2:4) gave slump (85mm) , And mix (1:3:6) gave (74mm) compare with
reference mixture
- Compressive strength for twelve cupics with optimum Gelenium ratio. The mix (1:1.5:3)
with (2%) gave (14Mpa) at early age. And (38Mpa) at finish age, least mix (1:2:4) gave
(10Mpa) at early age And (28Mpa) at finish age , And mix (1:3:6) gave (6Mpa) at early age
, and (20Mpa) at finish age as shown at figure(8).
- Depend on ratio of mix , percentage(w/c) and zoom of plasticizer .these factors gave best
result at mix(1:1.5:3) according to standard specification.

The present work studied the performance of a carbide tool with a chemical composition of (65%
W, 14 % Ti, 9 % Co and 12 % C). Turning tests were conducted on a workpiece of mild steel (AISI
1020) using four spindle speeds (80, 315, 500 and 800 rpm), two feed rates (0.2 and 0.5 mm/rev)
and two depth of cut (0.5 and 0.7 mm). Taguchi method is a statistical approach to optimize the
process parameters and improve the quality of components that are manufactured. The objective of
this study is using Taguchi method to optimize the machining conditions of a turning operation such
as spindle speed; feed rate and depth of cut. Orthogonal array, signal-to-noise ratio, and analysis of
variance were employed using Mtb14 software to study the performance characteristics on turning
operation represented by the tool life. Accordingly, a suitable mixed orthogonal array L16 (3×4)
was selected. The tool life was measured basing on a maximum flank wear width of 0.3
mm.Optimum parameter values were obtained and confirmation experiments were carried out. The
analysis results showed that the parameter design of the Taguchi method provides a simple,
systematic, and efficient methodology for optimizing the process parameters. Only 6.4 % error was
recorded. The regression analysis was applied using Datafit ver.9 software. The results of the
analysis showed that the non-linear quadratic polynomial appears to be more suitable to represent
the relation of the spindle speed, feed rate and depth of cut with the tool's wear lif

A free vibration analysis of isotropic thin circular plate with various edge conditions have been studied
in the present work. This study involves the obtaining of natural frequencies by solving the
mathematical model that governs the vibration behavior of the plate using finite difference method. The
numerical results of natural frequencies of circular plate are presented for different cases such as
aspect ratio, curvature effect, grid size and boundary conditions. A good results was obtained from
finite difference procedure compared with that obtained from the finite element analysis using Abaqus
Package program