Abstract: The legends about “user-friendly” and “easy-to-use”
birotical tools (computer-related office tools) have been spreading
and misleading end-users. This approach has led us to the extremely
high number of incorrect documents, causing serious financial losses
in the creating, modifying, and retrieving processes. Our research
proved that there are at least two sources of this underachievement:
(1) The lack of the definition of the correctly edited, formatted
documents. Consequently, end-users do not know whether their
methods and results are correct or not. They are not aware of their
ignorance. They are so ignorant that their ignorance does not allow
them to realize their lack of knowledge. (2) The end-users’ problem
solving methods. We have found that in non-traditional programming
environments end-users apply, almost exclusively, surface approach
metacognitive methods to carry out their computer related activities,
which are proved less effective than deep approach methods.
Based on these findings we have developed deep approach
methods which are based on and adapted from traditional
programming languages. In this study, we focus on the most popular
type of birotical documents, the text based documents. We have
provided the definition of the correctly edited text, and based on this
definition, adapted the debugging method known in programming.
According to the method, before the realization of text editing, a
thorough debugging of already existing texts and the categorization
of errors are carried out. With this method in advance to real text
editing users learn the requirements of text based documents and also
of the correctly formatted text.
The method has been proved much more effective than the
previously applied surface approach methods. The advantages of the
method are that the real text handling requires much less human and
computer sources than clicking aimlessly in the GUI (Graphical User
Interface), and the data retrieval is much more effective than from
error-prone documents.
Abstract: Diffusion stills have been effective in water
desalination. The present work represents a model of the distillation
process by using vertical single-effect diffusion stills. A semianalytical
model has been developed to model the process. A
software computer code using Engineering Equation Solver EES
software has been developed to solve the equations of the developed
model. An experimental setup has been constructed, and used for the
validation of the model. The model is also validated against former
literature results. The results obtained from the present experimental
test rig, and the data from the literature, have been compared with the
results of the code to find its best range of validity. In addition, a
parametric analysis of the system has been developed using the
model to determine the effect of operating conditions on the system's
performance. The dominant parameters that affect the productivity of
the still are the hot plate temperature that ranges from (55- 90°C) and
feed flow rate in range of (0.00694-0.0211 kg/m2-s).
Abstract: PLA emerged as a promising polymer because of its
property as a compostable, biodegradable thermoplastic made from
renewable sources. PLA can be polymerized from monomers
(Lactide or Lactic acid) obtained by fermentation processes from
renewable sources such as corn starch or sugarcane. For PLA
synthesis, ring opening polymerization (ROP) of Lactide monomer is
one of the preferred methods. In the literature, the technique mainly
developed for ROP of PLA is based on metal/bimetallic catalyst (Sn,
Zn and Al) or other organic catalysts in suitable solvent. However,
the PLA synthesized using such catalysts may contain trace elements
of the catalyst which may cause toxicity. This work estimated the
usefulness and drawbacks of using different catalysts as well as effect
of alternative energies and future aspects for PLA production.
Abstract: The study examined the effect of Bonny Light whole
crude oil (WC) and its water soluble fraction (WSF) on the activities
of antioxidant enzymes (catalase (CAT) and superoxide dismutase
(SOD)) and crude mitochondria ATPases in the radicle of
germinating bean (Vigna unguiculata). The percentage germination,
level of lipid peroxidation, antioxidant enzyme and mitochondria
Ca2+ and Mg2+ ATPase activities were measured in the radicle of
bean after 7, 14 and 21 days post germination. Viable bean seeds
were planted in soils contaminated with 10ml, 25ml and 50ml of
whole crude oil (WC) and its water soluble fraction (WSF) to obtain
2, 5 and 10% v/w crude oil contamination. There was dose dependent
reduction of the number of bean seeds that germinated in the
contaminated soils compared with control (p
Abstract: This study was conducted to investigate the effect of
the antioxidant activity of germinated African Yam Bean (AYB) on
oxidative stress markers in alloxan induced diabetic rat. Rats were
randomized into three groups; control, diabetic and germinated AYB
– treated diabetic rats. The Total phenol and flavonoid content and
DPPH radical scavenging activity before and after germination were
investigated. The glucose level, lipid peroxidation and reduced
glutathione of the animals were also determined using standard
technique for four weeks. Germination increased the total phenol,
flavonoid and antioxidant activity of AYB extract by 19.14%,
32.28% and 57.25% respectively. The diabetic rats placed on
germinated AYB diet had a significant decrease in the blood glucose
and lipid peroxidation with a corresponding increase in glutathione
(p
Abstract: Thin ZnO films are deposited on glass substrates via
sol–gel method and dip-coating. The films are prepared from zinc
acetate dehydrate as a starting reagent. After that the as-prepared
ZnO sol is aged for different periods (0, 1, 3, 5, 10, 15 and 30 days).
Nanocrystalline thin films are deposited from various sols. The
effect ZnO sols aging time on the structural and photocatalytic
properties of the films is studied. The films surface is studied by
Scanning Electron Microscopy. The effect of the aging time of the
starting solution is studied in the photocatalytic degradation of
Reactive Black 5 (RB5) by UV-vis spectroscopy. The experiments
are conducted upon UV-light illumination and in complete darkness.
The variation of the absorption spectra shows the degradation of RB5
dissolved in water, as a result of the reaction, occurring on the surface
of the films and promoted by UV irradiation. The initial
concentrations of dye (5, 10 and 20 ppm) and the effect of the aging
time are varied during the experiments. The results show, that the
increasing aging time of starting solution with respect to ZnO
generally promotes photocatalytic activity. The thin films obtained
from ZnO sol, which is aged 30 days have best photocatalytic
degradation of the dye (97,22%) in comparison with the freshly
prepared ones (65,92%). The samples and photocatalytic
experimental results are reproducible. Nevertheless, all films exhibit
a substantial activity in both UV light and darkness, which is
promising for the development of new ZnO photocatalysts by sol-gel
method.
Abstract: The temperature dependence of wettability (wetting
angle, Θ (T)) for Ag-based melts on graphite and Al2O3 substrates is
compared. Typical alloying effects are found, as the Ag host metal is
gradually replaced by various metallic elements. The essence of
alloying lies in the change of the electron/atom (e/a) ratio. This ratio
is also manifested in the shift of wetting angles on the same substrate.
Nevertheless, the effects are partially smeared by other
(metallurgical) factors, like the interaction between the oxygenalloying
elements and by the graphite substrate-oxygen interaction. In
contrast, such effects are not pronounced in the case of Al2O3
substrates. As a consequence, Θ(T) exhibits an opposite trend in the
case of two substrates. Crossovers of the Θ(T) curves were often
found. The positions of crossovers depend on the chemical character
and concentration of solute atoms. Segregation and epitaxial texture
formation after solidification were also observed in certain alloy
drops, especially in high concentration range. This phenomenon is
not yet explained in every detail.
Abstract: This review emphasizes the effectiveness of men’s
participation in preventing domestic violence, and whether nonviolent
(NV) boys’ and men’s perceptions of intimate partner
violence (IPV) prevention programs affect their involvement. The
main goals of this assessment were to investigate (1) how NV men
engaged in anti-violence prevention programs that empower women,
(2) what were the possible perceptions of NV men involved in
prevention programs (3) how to identify effective approaches and
strategies that encouraged NV men to become involved in prevention
programs. This critical review also included the overview of
prevention programs such as: The Mentors in Violence Prevention
Programs (MVP), The White Ribbon Campaign (WRC), and
Domestic Violence Prevention Enhancement and Leadership through
Alliances (DELTA). The review suggested that (1) the expanding
prevention programs need to reach more macro settings such as work
place, faith-based and other community based organizations, and (2)
territory prevention programs should expand through addressing the
long-term effects of violence.
Abstract: These days, the field of tissue engineering is getting
serious attention due to its usefulness. Bone tissue engineering helps
to address and sort-out the critical sized and non-healing orthopedic
problems by the creation of manmade bone tissue. We will design
and validate an efficient numerical model, which will simulate the
effective diffusivity in bone tissue engineering. Our numerical model
will be based on the finite element analysis of the diffusion-reaction
equations. It will have the ability to optimize the diffusivity, even
at multi-scale, with the variation of time. It will also have a special
feature “parametric sweep”, with which we will be able to predict
the oxygen, glucose and cell density dynamics, more accurately. We
will fix these problems by modifying the governing equations, by
selecting appropriate spatio-temporal finite element schemes and by
transient analysis.
Abstract: Since columns are the most important elements of the
structures, failure of one column in a critical location can cause a
progressive collapse. In this respect, the repair and strengthening of
columns is a very important subject to reduce the building failure and
to keep the columns capacity. Twenty columns with different
parameters is tested and analysis. Eleven typical confined reinforced
concrete (RC) columns with different types of techniques are
assessment. And also, four confined concrete columns with plastic
tube (PVC) are tested with and with four paralleling tested of
unconfined plain concrete. The techniques of confined RC columns
are mortar strengthening, Steel rings strengthening, FRP
strengthening. Moreover, the technique of confined plain concrete
(PC) column is used PVC tubes. The columns are tested under
uniaxial compressive loads studied the effect of confinement on the
structural behavior of circular RC columns. Test results for each
column are presented in the form of crack patterns, stress-strain
curves. Test results show that confining of the RC columns using
different techniques of strengthening results significant improvement
of the general behavior of the columns and can used in construction.
And also, tested confined PC columns with PVC tubes results shown
that the confined PC with PVC tubes can be used in economical
building. The theoretical model for predicted column capacity is
founded with experimental factor depends on the confined techniques
used and the strain reduction.
Abstract: A compact UWB planar antenna fed with a
microstrip-line is proposed. The new design consist of a rectangular
patch with symmetric l-shaped slots and fed by 50 Ω microstrip
transmission line and a reduced ground-plane which have a periodic
slots with an overall size of 47 mm x 20 mm. It is intended to be used
in wireless applications that cover the ultra-wideband (UWB)
frequency band. A wider impedance bandwidth of around 116.5%
(1.875 – 7.115 GHz) with stable radiation pattern is achieved. The
proposed antenna has excellent characteristics, low profile and costeffective
compared to existing UWB antennas. The UWB antenna is
designed and analyzed using CST Microwave Studio in transient
mode to verify antenna parameters improvements.
Abstract: This study carried out comparative seismic
performance of reinforced concrete frames infilled by masonry walls
with different heights. Partial and fully infilled reinforced concrete
frames were modeled for the research objectives and the analysis
model for a bare reinforced concrete frame was also established for
comparison. Non–linear static analyses for the studied frames were
performed to investigate their structural behavior under extreme
seismic loads and to find out their collapse mechanism. It was
observed from analysis results that the strengths of the partial infilled
reinforced concrete frames are increased and their ductilities are
reduced, as infilled masonry walls are higher. Especially, reinforced
concrete frames with higher partial infilled masonry walls would
experience shear failures. Non–linear dynamic analyses using 10
earthquake records show that the bare and fully infilled reinforced
concrete frame present stable collapse mechanism while the reinforced
concrete frames with partially infilled masonry walls collapse in more
brittle manner due to short-column effects.
Abstract: Waste silicon carbide (waste SiC) filled high-density
polyethylene (HDPE) with and without surface modifiers were
studied. Two types of surface modifiers namely; high-density
polyethylene-grafted-maleic anhydride (HDPE-g-MA) and 3-aminopropyltriethoxysilane have been used in this study. The
composites were produced using a two roll mill, extruder and shaped
in a hydraulic compression molding machine. The mechanical
properties of polymer composites such as flexural strength and
modulus, impact strength, tensile strength, stiffness and hardness
were investigated over a range of compositions. It was found that,
flexural strength and modulus, tensile modulus and hardness
increased, whereas impact strength and tensile strength decreased
with the increasing in filler contents, compared to the neat HDPE. At
similar filler content, the effect of both surface modifiers increased
flexural modulus, impact strength, tensile strength and stiffness but
reduced the flexural strength. Morphological investigation using
SEM revealed that the improvement in mechanical properties was
due to enhancement of the interfacial adhesion between waste SiC
and HDPE.
Abstract: In this paper, the effect of grades 32.4 and 42.5
Portland-limestone cements generally used for concrete production in
Nigeria on concrete compressive strength is investigated.
Investigation revealed that the compressive strength of concrete
produced with Portland-limestone cement grade 42.5 is generally
higher than that produced with cement grade 32.5. The percentage
difference between the compressive strengths of the concrete cubes
produced with Portland-limestone cement grades 42.5 and 32.5 is
inversely proportional to the richness of the concrete with the highest
and the least percentage difference associated with the 1:2:4 and
1:1:2 mix ratios respectively. It is recommended that cement grade
42.5 be preferred for construction in Nigeria as this will lead to the
construction of stronger concrete structures, which will reduce the
incidence of failure of building and other concrete structures at no
additional cost since the cost of both cement grades are the same.
Abstract: Teachers can play a huge role in encouraging students
to use computers and can affect students’ attitudes towards
computers. So understanding teachers’ beliefs and their use of
computers is an important way to create effective motivational
systems for teachers to use computers in the classroom in an effective
way. A qualitative study (6 focus group) was carried out among
Saudi High school teachers, both male and female, to examine their
attitudes towards computers and to find out their computer skills and
usage. The study showed a gender differences in that females were
less likely to attend computer workshops, females also had less
computer skills, and they have more negative attitudes towards
computers than males. Also the study found that low computer skills
in the classroom made students unlikely to have the lessons presented
using computers. Furthermore, the study found some factors that
effected teachers’ attitudes towards computers. These factors were
computer experience and confidence as much having skills and good
experience in computer use, the role and importance of computers
had become in their life and in teaching as well.
Abstract: The well been of human beings on construction site is
very important, many man power had been lost through accidents
which kills or make workers physically unfit to carry out construction
activities, these in turn have multiple effects on the whole economy.
Thus it is necessary to put all safety items and regulations in place
before construction activities can commence. This study was carried
out in Ondo state of Nigeria to known and analyse the state of health
and safety of construction workers in the state. The study was done
using first hand observation method, 50 construction project sites
were visited in 10 major towns of Ondo state, questionnaires were
distributed and the results were analysed. The result show that
construction workers are being exposed to a lot of construction site
hazards due to lack of inadequate safety programmes and nonprovision
of appropriate safety materials for workers on site. From the
data gotten for each site visited and the statistical analysis, it can be
concluded that occurrence of accident on construction sites depends
significantly on the available safety facilities on the sites. The result of
the regression statistics show that the level of significant of the
dependence of occurrence of accident on the availability of safety
items on site is 0.0362 which is less than 0.05 maximum significant
level required. Therefore a vital way of sustaining our building
strategy is by given a detail attention to provision of adequate health
and safety items on construction sites which will reduce the
occurrence of accident, loss of man power and death of skilled
workers among others.
Abstract: Background: The effectiveness of mirror therapy
(MT) has been investigated in acute hemiplegia. The present study
examines whether MT, given during chronic stroke, was more
effective in promoting motor recovery of the lower extremity and
walking speed than standard rehabilitation alone. Methods: The study
enrolled 30 patients with chronic stroke. Fifteen patients each were
assigned to the treatment group and the control group. All patients
received a conventional rehabilitation program for a 4-week period.
In addition to this rehabilitation program, patients in the treatment
group received mirror therapy for 4 weeks, 5 days a week. Main
measures: Passive ankle joint dorsiflexion range of motion, gait
speed, Brunnstrom stages of motor recovery, plantar flexor muscle
tone by Modified Ashworth Scale. Results: No significant difference
was found in the outcome measures among groups before treatment.
When compared with standard rehabilitation, mirror therapy
improved Ankle ROM, Brunnstrom stages and waking speed
(p < 0.05). However, there were no significant differences between
two groups on MAS (P > 0.05).Conclusion: Mirror therapy combined
with a conventional stroke rehabilitation program enhances lowerextremity
motor recovery and walking speed in chronic stroke
patients.
Abstract: Sandwich structure composites produced by epoxy
core and aluminium skin were developed as potential building
materials. Interface bonding between core and skin was controlled by
varying kenaf content. Five different weight percentage of kenaf
loading ranging from 10 wt% to 50 wt% were employed in the core
manufacturing in order to study the mechanical properties of the
sandwich composite. Properties of skin aluminium with epoxy were
found to be affected by drying time of the adhesive. Mechanical
behavior of manufactured sandwich composites in relation with
properties of constituent materials was studied. It was found that 30
wt% of kenaf loading contributed to increase the flexural strength and
flexural modulus up to 102 MPa and 32 GPa, respectively. Analysis
were done on the flatwise and edgewise compression test. For
flatwise test, it was found that 30 wt% of fiber loading could
withstand maximum force until 250 kN, with compressive strength
results at 96.94 MPa. However, at edgewise compression test, the
sandwich composite with same fiber loading only can withstand 31
kN of the maximum load with 62 MPa of compressive strength
results.
Abstract: This study was carried out to evaluate the nutritional
composition of the African River Prawn (Macrobrachium
vollenhovenii) in relation to Chokor (traditional) and Altona
(improved traditional) drying techniques used in the preservation and
processing of prawns by carrying out proximate composition
analysis. The value obtained for the proximate analysis of Chokor
and Altona smoke dried prawns were; Moisture (14.90% and
15.15%), Dry matter (85.10% and 84.85%), Protein (55.80% and
58.87%), Crude fat (1.95% and 1.98%), Crude fibre (21.40% and
13.11%), Carbohydrate (0.54% and 0.54%) and Ash (19.76% and
15.86%) respectively. The proximate mineral composition of Chokor
and Altona smoke dried prawns were; Calcium (5.66% and 4.20%)
and Phosphorus (9. 22% and 6.34%) respectively. Result shows there
was no loss of nutritional value with respect to Chokor and Altona
drying techniques used in the processing of prawns.
Abstract: The present study was undertaken to investigate the
effect of aging parameters (time and temperature) on the mechanical
properties of Be-and/or Zr- treated Al-Mg-Zn (7075) alloys. Ultimate
tensile strength, 0.5% offset yield strength and % elongation
measurements were carried out on specimens prepared from cast and
heat treated 7075 alloys containing Be and/or Zr. Different aging
treatment were carried out for the as solution treated (SHT)
specimens (after quenching in warm water). The specimens were
aged at different conditions; Natural and artificial aging was carried
out at room temperature, 120C, 150C, 180C and 220C for different
periods of time. Duplex aging was performed for SHT conditions
(pre-aged at different time and temperature followed by high
temperature aging). Ultimate tensile strength, yield strength and %
elongation data results as a function of different aging parameters are
analysed. A statistical design of experiments (DOE) approach using
fractional factorial design is applied to acquire an understanding of
the effects of these variables and their interactions on the mechanical
properties of Be- and/or Zr- treated 7075 alloys. Mathematical
models are developed to relate the alloy mechanical properties with
the different aging parameters.