Journal of Science and Engineering Applications

In the recent years, researchers have been interested in planning of layout of projects´ site since it is a
basic factor for a successful project undertaking. Projects´ sites comprise temporary facilities and heavy
construction equipment that share the same space or may require the same area of construction site,
therefore, construction site should be organized well, so that construction activity will be in its full swing.
The site layout planning process includes identifying the needed temporary facilities for supporting
operations of construction, specifying their shapes and sizes, and optimizing their positions within the
boundaries of sites. In this review, a number of methods and techniques used for construction site layout
planning are reviewed and discussed, the frequent problems at construction sites are included, the ways of
improving the efficiency of planning of sites layout are listed and discussed. The advantages of good
planning of sites layout and the effects of neglecting sites layout planning are reviewed.

Crashworthiness improvement of under-ride guard system of heavy vehicle design is a highly challenge duty
to save passengers life and prevent sever injures of small car in collisions. As a consequence of absence or
lack of the powerful under-run guard connected to the rear, side of trucks, trailers and semi-trailers, back
under-ride accidents are in charge of a huge death numbers in all the world. This study concentrates on
improving Rear Underrun Protection Device (RUPD) structure utilizing Finite Element Analysis apparatus
like LS-DYNA. Two designs of under-ride guard devise crushed using Toyota Yaris (2010) with different
impact speeds 45km/h and 63km/h. A zero passenger compartment intrusion (PCI) is accomplished with the
investment of the recently outlined under-ride guard for rear of trucks. The new under-ride guard model is
validated utilizing FMVSS 223/224 regulations. The new design achieved the goal of decreasing the
acceleration beyond the limits, which leads to decrease the
head injury criteria (HIC) to (373.250).

Power conversion in PV cells is limited to 15-20% from the incident radiation. That conversion
Suffers a severe drop with the rise of the PV cell temperature by 0.45~0.5% for each degree centigrade rise.
The primary objective of this study is to reduce the cell temperature using front face cooling. A CFD model
has been designed using COMSPL Multiphysics 5.3 to investigate the effect of water input temperature and
the change of the water flow rate. A physical model was also utilized using two 330 PV panels for
comparing the results at the same environmental conditions. The study shows that the PV cell efficiency
could be increased by 22.8% using a 2 mm nozzle diameter and 4 L.P.M water flow rates.

Removal of isopropyl alcohol and isobutyl alcohol vapors from air by activated carbon was carried out.
The equilibrium data for single component systen1s were obtained at different temperatures 301, 308, 3 J9
and 327 K. The equilibrium data for binary system was found at temperature 319 K. The equilibrium
isotherm results for single and binary components fit very well with Langmuir's isotherm. The effect of the
inlet concentration on the dynamic capacity, MTZ velocity, MTZ length and thermal wave velocity was
studied for single and binary systems. Empirical correlations describing these variables were determined. A
mathematical model was used to predict the breakthrough curves and temperature profiles. These results
were in good agreement with the experimental results.

Detecting direction of arrival (DoA) using array antenna is considered as common challenge in different
typeS of applications, such as sonar, radar, wireless communications. DoA estimation plays an important
role in direction finding applications. Further, effective DoA estimation technique is the primary
requirements for smart antenna system to realize beam forming technique. Multiple signal classification
(MUSIC) and Estimation of Signal Parameters via Rotational Invariance (ESPRIT) algorithms have been
widely studied, and they are considered as fundamental for the majority of the DoA methods in literature. In
this paper, the principal of DoA estimations is presented. The main focus of the current paper is on the
classical methods (Bartletts and MVDR), MUSIC and ESPRIT algorithms. Review of various efforts that
have been made to enhance the performance of these algorithms was acheived. Then compared their
performances using simulation results. Further, applying MUSIC algorithm to estimate the frequency of the
multiple incident signals. The results show that MUSIC algorithm has higher resolution compared to other
presented techniques. It is also shown that the accuracy of ESPRIT method is mainly rely on the number of
antenna elements. Finally, the principle of Eigenvalues-based method was proposed. It is shown that this
method has good resolution with very low complexity as it does not need decomposition of covariance
matrix.

The shortage of potable water is the biggest problem of the world in this century because of
the population growth and unsustainable water consumption rates. About half of the world’s population in
88 developing countries are affected by water crises which results in 80-90% of all diseases and 30% of all
deaths. Since water shortage is directly related to poverty, low cost, especially solar, seawater desalination
methods can help alleviate this trouble.
In which present research, an experimental study was presented for a novel stepwise solar still
accompanied by two units, a compound parabolic solar collector as a preheater and heat exchanger after
condenser. A computer model has been developed, according to thermal energy balance equations to
predict the transient performance of the system. The experimental in this study was achieved by
constructing the test rig that verify the theoretical results by practically real field testing.
Results achieved from this study demonstrate clearly the importance of rising the feed (saline water)
temperature, increasing the condensation surface area and further heating of evaporation surface; Using
new still absorber design, that increase the system productivity (91.3%) compared with the conventional
solar still yield. This shows obviously that solar still output is affected largely by changing design
parameters.

Reducing cell temperature is very important to improve cell efficiency and increase
electrical output. This study indicates the need to reduce losses in the process of cooling the PV
cell by controlling the air flow rate where the highest electrical efficiency of the cell at the
airflow rate (0.049 kg/s). The results showed that the rate of reduction of the temperature of the
cell reached (37.22%), and the temperature of the cell decreased by (22.2782 °C) as a result of
cooling using air guides. The heat generated by the cooling process can be utilized in multiple
applications as the difference between the inlet and outlet temperature of the air duct reached
(13.717°C), and the increase in the thermal efficiency of the PV cell (68.7%).