AL-Rafidain Engineering Journal (AREJ)

In this paper the SnO2 will be examined to be used as a transparent
antireflection coating with the n –type silicon wafer to fabricate the
deposited SnO2 silicon Solar cell using vacuum evaporation technique.
This SnO2 layer is simultaneously an antireflecting coating and a
transparent upper contact. The oxidation of the Si surface takes place
simultaneously with the evaporation process. A semiconductor –
insulator – semiconductor (SIS) structure was obtained in such a way.
The photoelectrical parameters of such SIS system of AM 1.5 conditions
are: the short circuit current 18.5 mA/cm2, the open circuit voltage 0.48
V and the efficiency is 7.0%. The subgap response of the resulted
structure is particularly strong and extends to wavelength up to 1100nm

The present study defines the research problem as a reconsideration or
reformulation of a scientific approach to study of the relation(s) between the
transparency of the individualistic style and the collective styles in Islamic
architecture. The research has adopted a literary approach in its analysis
namely: Riffaterre structure approach and Yaul’s statistical measurement.
Both styles have been compared for differences so as to find out whether there is
a complementary relation between both styles or there is a divorce betweenthem. It has been found that repetition of a architectural elements provides a
common meeting for both style. The study samples include Ottoman mosques
taken as elements and as relations as they represent the early, the classic and the
late styles with representative samples of (3) mosques for each period. It has
been found that the individualistic style is a pure reflection and continuation of the collective style and there is no creativity as the fundamentals are concerned.

The static Synchronous Compensator (STATCOM) is a solid-state shunt
device that generates or absorbs reactive power and is one member of a family
devices known as Flexible AC Transmission System (FACTS) devices. It is
superior to the static VAR Compensator (SVC) in many ways.
In this work it is suggested to use the (STATCOM) in the existing H.V. Iraqi
North Region National Grid (INRNG) for the first time. The best location of the
(STATCOM) is obtained using load flow study which is also used to determine
the optimal value of the reactive power needed at different load conditions. The
paper discusses a method of optimizing the operation of the (STATCOM) using
intelligent techniques. The method uses the Artificial Neural Network (ANN).
The obtained results using load flow program are considered as the input data
to train the (ANN). Then any value within the training data limit can be used to
get the optimal value of the (STATCOM) output. The data of the (INRNG) for
the year 2001 is used to verify the validity of the proposed method.

Mosul city suffers from high water tables. This problem appears clearly during
the rainy season. In this research thirty wells were chosed in an area in Mosul city
on both sides of the Tigris river. A topographical map was prepared after surveying
the area above the mean sea level. Then the water levels in these wells are
measured every month during the rainy season (2001 -2002). The sources of
ground water recharge were determined.The computer program ( surfer 32) is used
for preparing contour maps. Also the seasonal variations of the ground water levels
were studied. The results show that the rain was the main source for recharging the
ground water. The maximum levels of the water table in the wells occurred in March
and minimum levels in October. In 20% of the wells, the water levels less than one
meter from the surface of the ground. The ground water moves in both sides of the study area toward Tigris river. Different solutions were proposed to minimize the water table in the area under study.

The current system called Expert System for Analysis and Control of Water
Hammer Problems “ESACWHP” is developed to help engineers in the design and
analysis of water hammer problems using the characteristic method with aid of the
programming language called Visual Basic.
Results obtained from the developed of “ESACWHP” show good agreement
with that solved by traditional lengthy methods, in addition it is capable of handling
more variables. The system is recommended to be used for analysis and design

An Electro-Cardio-Graph (ECG) is a device that records the electrical
activity of the heart. Skin electrodes placed at designated locations on the body
collect ECG measurement information, and from these waveforms different
information on heart condition can be derived.
This paper discusses the design and implementation of a single-channel ECG
(three-electrode) circuit with a bandwidth of (0.5-100) Hz for patient monitoring
purposes. The front end of an ECG must be able to deal with weak signals ranging
from few microvolts to few millivolts. An analogue ECG amplifier is designed and
implemented using instrumentation amplifier (IA) followed by band pass filter
(BPF), then by notch filter (NF) to minimize noise affecting the signal, and a right
leg drive circuit (RLDC). .
The ECG data is recorded and analyzed with greater flexibility using personal
computer. The (ALS 4000) PC-sound card is used as a data acquisition device. The
Matlab program (version 6.5) is employed to acquire data from sound card then
digitally processing the signal in order to display the ECG signal on a PC monitor.