Abstract: The present paper attempts to investigate the
prediction of air entrainment rate and aeration efficiency of a free
overfall jets issuing from a triangular sharp crested weir by using
regression based modelling. The empirical equations, Support vector
machine (polynomial and radial basis function) models and the linear
regression techniques were applied on the triangular sharp crested
weirs relating the air entrainment rate and the aeration efficiency to
the input parameters namely drop height, discharge, and vertex angle.
It was observed that there exists a good agreement between the
measured values and the values obtained using empirical equations,
Support vector machine (Polynomial and rbf) models and the linear
regression techniques. The test results demonstrated that the SVM
based (Poly & rbf) model also provided acceptable prediction of the
measured values with reasonable accuracy along with empirical
equations and linear regression techniques in modelling the air
entrainment rate and the aeration efficiency of a free overfall jets
issuing from triangular sharp crested weir. Further sensitivity analysis
has also been performed to study the impact of input parameter on the
output in terms of air entrainment rate and aeration efficiency.
Abstract: Nowadays, energy dissipation devices are commonly
used in structures. High rate of energy absorption during earthquakes
is the benefit of using such devices, which results in damage
reduction of structural elements, specifically columns. The hysteretic
damping capacity of energy dissipation devices is the key point that it
may adversely make analysis and design process complicated. This
effect may be generally represented by Equivalent Viscous Damping
(EVD). The equivalent viscous damping might be obtained from the
expected hysteretic behavior regarding to the design or maximum
considered displacement of a structure. In this paper, the hysteretic
damping coefficient of a steel Moment Resisting Frame (MRF),
which its performance is enhanced by a Buckling Restrained Brace
(BRB) system has been evaluated. Having foresight of damping
fraction between BRB and MRF is inevitable for seismic design
procedures like Direct Displacement-Based Design (DDBD) method.
This paper presents an approach to calculate the damping fraction for
such systems by carrying out the dynamic nonlinear time history
analysis (NTHA) under harmonic loading, which is tuned to the
natural system frequency. Two MRF structures, one equipped with
BRB and the other without BRB are simultaneously studied.
Extensive analysis shows that proportion of each system damping
fraction may be calculated by its shear story portion. In this way,
contribution of each BRB in the floors and their general contribution
in the structural performance may be clearly recognized, in advance.
Abstract: Anammox is a novel and promising technology that has changed the traditional concept of biological nitrogen removal. The process facilitates direct oxidation of ammonical nitrogen under anaerobic conditions with nitrite as an electron acceptor without addition of external carbon sources. The present study investigated the feasibility of Anammox Hybrid Reactor (AHR) combining the dual advantages of suspended and attached growth media for biodegradation of ammonical nitrogen in wastewater. Experimental unit consisted of 4 nos. of 5L capacity AHR inoculated with mixed seed culture containing anoxic and activated sludge (1:1). The process was established by feeding the reactors with synthetic wastewater containing NH4-H and NO2-N in the ratio 1:1 at HRT (hydraulic retention time) of 1 day. The reactors were gradually acclimated to higher ammonium concentration till it attained pseudo steady state removal at a total nitrogen concentration of 1200 mg/l. During this period, the performance of the AHR was monitored at twelve different HRTs varying from 0.25-3.0 d with increasing NLR from 0.4 to 4.8 kg N/m3d. AHR demonstrated significantly higher nitrogen removal (95.1%) at optimal HRT of 1 day. Filter media in AHR contributed an additional 27.2% ammonium removal in addition to 72% reduction in the sludge washout rate. This may be attributed to the functional mechanism of filter media which acts as a mechanical sieve and reduces the sludge washout rate many folds. This enhances the biomass retention capacity of the reactor by 25%, which is the key parameter for successful operation of high rate bioreactors. The effluent nitrate concentration, which is one of the bottlenecks of anammox process was also minimised significantly (42.3-52.3 mg/L). Process kinetics was evaluated using first order and Grau-second order models. The first-order substrate removal rate constant was found as 13.0 d-1. Model validation revealed that Grau second order model was more precise and predicted effluent nitrogen concentration with least error (1.84±10%). A new mathematical model based on mass balance was developed to predict N2 gas in AHR. The mass balance model derived from total nitrogen dictated significantly higher correlation (R2=0.986) and predicted N2 gas with least error of precision (0.12±8.49%). SEM study of biomass indicated the presence of heterogeneous population of cocci and rod shaped bacteria of average diameter varying from 1.2-1.5 mm. Owing to enhanced NRE coupled with meagre production of effluent nitrate and its ability to retain high biomass, AHR proved to be the most competitive reactor configuration for dealing with nitrogen laden wastewater.
Abstract: Objective: Sharing devastating news with patients is
often considered the most difficult task of doctors. This study aimed
to explore patients’ perceptions of receiving bad news including
which features improve the experience and which areas need refining. Methods: A questionnaire was written based on the steps of the
SPIKES model for breaking bad new. 20 patients receiving treatment
for a hematological malignancy completed the questionnaire. Results: Overall, the results are promising as most patients praised
their consultation. ‘Poor’ was more commonly rated by women and
participants aged 45-64. The main differences between the ‘excellent’
and ‘poor’ consultations include the doctor’s sensitivity and checking
the patients’ understanding. Only 35% of patients were asked their
existing knowledge and 85% of consultations failed to discuss the
impact of the diagnosis on daily life. Conclusion: This study agreed with the consensus of existing
literature. The commended aspects include consultation set-up and
information given. Areas patients felt needed improvement include
doctors determining the patient’s existing knowledge and checking
new information has been understood. Doctors should also explore
how the diagnosis will affect the patient’s life. With a poorer
prognosis, doctors should work on conveying appropriate hope. The
study was limited by a small sample size and potential recall bias.
Abstract: Ecological systems are exposed and are influenced by
various natural and anthropogenic disturbances. They produce
various effects and states seeking response symmetry to a state of
global phase coherence or stability and balance of their food webs.
This research project addresses the development of a computational
methodology for modeling plankton food webs. The use of
algorithms to establish connections, the generation of representative
fuzzy multigraphs and application of technical analysis of complex
networks provide a set of tools for defining, analyzing and evaluating
community structure of coastal aquatic ecosystems, beyond the
estimate of possible external impacts to the networks. Thus, this
study aims to develop computational systems and data models to
assess how these ecological networks are structurally and
functionally organized, to analyze the types and degree of
compartmentalization and synchronization between oscillatory and
interconnected elements network and the influence of disturbances on
the overall pattern of rhythmicity of the system.
Abstract: Communicating users' needs, goals and problems help
designers and developers overcome challenges faced by end users.
Personas are used to represent end users’ needs. In our research,
creating personas allowed the following questions to be answered:
Who are the potential user groups? What do they want to achieve by
using the service? What are the problems that users face? What
should the service provide to them? To develop realistic personas, we
conducted a focus group discussion with undergraduate and graduate
students and also interviewed a university librarian. The personas
were created to help evaluating the Institutional Repository that is
based on the DSpace system. The profiles helped to communicate
users' needs, abilities, tasks, and problems, and the task scenarios
used in the heuristic evaluation were based on these personas. Four
personas resulted of a focus group discussion with undergraduate and
graduate students and from interviewing a university librarian. We
then used these personas to create focused task-scenarios for a
heuristic evaluation on the system interface to ensure that it met
users' needs, goals, problems and desires. In this paper, we present
the process that we used to create the personas that led to devise the
task scenarios used in the heuristic evaluation as a follow up study of
the DSpace university repository.
Abstract: Fiber Reinforced Polymer (FRP) is a composite material with exceptional properties that are capable to replace conventional steel reinforcement in reinforced and pre-stressed concrete structures. However, the main obstacle for their wide use in pre-stressed concrete application is the anchorage system. Due to the weakness of FRP in the transverse direction, the pre-stressing capacity of FRP bars are limited. This paper investigates the modification of the conventional wedge anchorage system to be used for stressing of FRP bars in pre-stressed applications. Epoxy adhesive material with glass FRP (GFRP) bars and conventional steel wedge were used in this paper. The GFRP bars are encased with epoxy at the anchor zone and the wedge system was used in pull-out test. The results showed a loading capacity of 47.6 kN which is 69% of the bar ultimate capacity. Additionally, nylon wedge was made with the same dimensions of the steel wedge and tested for GFRP bars without epoxy layer. The nylon wedge showed a loading capacity of 19.7 kN which is only 28.5% of the ultimate bar capacity.
Abstract: It is the patient compliance and stability in
combination with controlled drug delivery and biocompatibility that
forms the core feature in present research and development of
sustained biodegradable patch formulation intended for wound
healing. The aim was to impart sustained degradation, sterile
formulation, significant folding endurance, elasticity,
biodegradability, bio-acceptability and strength. The optimized
formulation comprised of polymers including Hydroxypropyl methyl
cellulose, Ethylcellulose, and Gelatin, and Citric Acid PEG Citric
acid (CPEGC) triblock dendrimers and active Curcumin. Polymeric
mixture dissolved in geometric order in suitable medium through
continuous stirring under ambient conditions. With continued stirring
Curcumin was added with aid of DCM and Methanol in optimized
ratio to get homogenous dispersion. The dispersion was sonicated
with optimum frequency and for given time and later casted to form a
patch form. All steps were carried out under strict aseptic conditions.
The formulations obtained in the acceptable working range were
decided based on thickness, uniformity of drug content, smooth
texture and flexibility and brittleness. The patch kept on stability
using butter paper in sterile pack displayed folding endurance in
range of 20 to 23 times without any evidence of crack in an
optimized formulation at room temperature (RT) (24 ± 2°C). The
patch displayed acceptable parameters after stability study conducted
in refrigerated conditions (8±0.2°C) and at RT (24 ± 2°C) up to 90
days. Further, no significant changes were observed in critical
parameters such as elasticity, biodegradability, drug release and drug
content during stability study conducted at RT 24±2°C for 45 and 90
days. The drug content was in range 95 to 102%, moisture content
didn’t exceeded 19.2% and patch passed the content uniformity test.
Percentage cumulative drug release was found to be 80% in 12h and
matched the biodegradation rate as drug release with correlation
factor R2>0.9. The biodegradable patch based formulation developed
shows promising results in terms of stability and release profiles.
Abstract: This study aimed to explore the practical experience
of child welfare caseworkers and professionalism in child case
management in Malaysia. This paper discussed the specific social
work practice competency and the challenges faced by child
caseworkers in the fieldwork. This research was qualitative with
grounded theory approach. Four sessions of focused group discussion
(FGD) were conducted involving a total of 27 caseworkers (child
protector and probation officers) in the Klang Valley. The study
found that the four basic principles of knowledge in child case
management namely: 1. knowledge in child case management; 2.
professional values of caseworkers towards children; 3. skills in
managing cases; and 4. culturally competent practice in child case
management. In addition, major challenges faced by the child case
manager are the capacity and commitment of the family in children’s
rehabilitation program, the credibility of caseworkers are being
challenged, and the challenges of support system from intra and interagency.
This study is important for policy makers to take into account
the capacity and the needs of the child’s caseworker in accordance
with the national social work competency framework. It is expected
that case management services for children will improve
systematically in line with national standards.
Abstract: The research aims to study the association between
job satisfaction, motivation and the five factors of organizational
citizenship behavior (i.e. Altruism, Conscientiousness,
Sportsmanship, Courtesy and Civic virtue) among Public Sector
Employees in Pakistan. In this research Structure Equation Modeling
with confirmatory factor analysis was used to test the relationship
between two independent and five dependent variables. Data was
collected through questionnaire survey from 152 Public Servants
Working in Gujrat District-Pakistan in different capacities. Stratified
Random Sampling Technique was used to conduct this survey. The
results of the study indicate that five factors of OCB have positive
significant relation with both motivation and job satisfaction except
the relationship of Civic Virtue with Motivation. The research
findings implicate that factors other than motivation and job
satisfaction may also affect OCB. Likewise, all the five factors of
OCB may not be present in all populations. Thus, Managers must
concentrate on increasing motivation and job satisfaction to increase
OCB. Furthermore, the present research gives a direction to future
researchers to use more independent variables (e.g. Culture,
leadership, workplace environment, various job attitudes, types of
motivation, etc.) on different types of populations with larger sample
size in order to find the reasons behind insignificant relationship of
civic virtue with Motivation in the research in hand and to generalize
the tested model.
Abstract: The current paper presents the results of a conducted
case study. During the past few years the number of children
diagnosed with Learning Difficulties has drastically augmented and
especially the cases of ADHD (Attention Deficit Hyperactivity
Disorder). One of the core characteristics of ADHD is a deficit in
working memory functions. The review of the literature indicates a
plethora of educational software that aim at training and enhancing
the working memory. Nevertheless, in the current paper, the
possibility of using for the same purpose free, online games will be
explored. Another issue of interest is the potential effect of the
working memory training to the core symptoms of ADHD. In order
to explore the abovementioned research questions, three digital tests
are employed, all of which are developed on the E-slate platform by
the author, in order to check the levels of ADHD’s symptoms and to
be used as diagnostic tools, both in the beginning and in the end of
the case study. The tools used during the main intervention of the
research are free online games for the training of working memory.
The research and the data analysis focus on the following axes: a) the
presence and the possible change in two of the core symptoms of
ADHD, attention and impulsivity and b) a possible change in the
general cognitive abilities of the individual. The case study was
conducted with the participation of a thirteen year-old, female
student, diagnosed with ADHD, during after-school hours. The
results of the study indicate positive changes both in the levels of
attention and impulsivity. Therefore, we conclude that the training of
working memory through the use of free, online games has a positive
impact on the characteristics of ADHD. Finally, concerning the
second research question, the change in general cognitive abilities, no
significant changes were noted.
Abstract: Multiple-input multiple-output (MIMO) radar has
received increasing attention in recent years. MIMO radar has many
advantages over conventional phased array radar such as target
detection,resolution enhancement, and interference suppression. In
this paper, the results are presented from a simulation study of MIMO
uniformly-spaced linear array (ULA) antennas. The performance is
investigated under varied parameters, including varied array size,
pseudo random (PN) sequence length, number of snapshots, and
signal to noise ratio (SNR). The results of MIMO are compared to a
traditional array antenna.
Abstract: Mobile Ad Hoc Networks (MANETs) is a collection
of mobile devices forming a communication network without
infrastructure. MANET is vulnerable to security threats due to
network’s limited security, dynamic topology, scalability and the lack
of central management. The Quality of Service (QoS) routing in such
networks is limited by network breakage caused by node mobility or
nodes energy depletions. The impact of node mobility on trust
establishment is considered and its use to propagate trust through a
network is investigated in this paper. This work proposes an
enhanced Associativity Based Routing (ABR) with Fuzzy based
Trust (Fuzzy- ABR) routing protocol for MANET to improve QoS
and to mitigate network attacks.
Abstract: The increasing volume of solid waste generated,
collected and disposed daily complicate adequate management of
solid waste by relevant agency like Niger State Environmental
Protection Agency (NISEPA). In addition, the impacts of solid waste
on the natural environment and human livelihood require
identification of cost-effective ways for sustainable municipal waste
management in Nigeria. These signal the need for identifying
environment-friendly initiative and local solution to address the
problem of municipal solid waste. A research field was secured at
Pago, Minna, Niger State which is located in the guinea savanna belt
of Nigeria, within longitude 60 361 4311 - 4511 and latitude 90 291
37.6111 - .6211 N. Poultry droppings, decomposed household waste
manure and NPK treatments were used. The experimental field was
divided into three replications and four (4) treatments on each
replication making a total of twelve (12) plots. The treatments were
allotted using Randomized Complete Block Design (RCBD) and
Data collected was analyzed using SPSS software and RCBD. The
result depicts variation in plant height and number of leaves at 50%
flowering; Poultry dropping records the highest height while the
number of leaves for waste manure competes fairly well with NPK
treatment. Similarly, the varying treatments significantly increase
vegetable yield, as the control (non-treatment) records the least yield
for the three vegetable samples. Adoption of this organic manure for
cultivation does not only enhance environment quality and attainment
of food security but will contribute to local economic development,
poverty alleviation as well as social inclusion.
Abstract: A new design of aerostatic thrust bearing is proposed
for high static stiffness. The bearing body, which is mead of polymer
covered with metallic membrane, is held by a circular ring. Such a
support helps form a concave air gap to grasp the air pressure. The
polymer body, which can be made rapidly by either injection or
molding is able to provide extra damping under dynamic loading. The
smooth membrane not only serves as the bearing surface but also
protects the polymer body. The restrictor is a capillary inside a silicone
tube. It can passively compensate the variation of load by expanding
the capillary diameter for more air flux. In the present example, the
stiffness soars from 15.85 N/μm of typical bearing to 349.85 N/μm at
bearing elevation 9.5 μm; meanwhile the load capacity also enhances
from 346.86 N to 704.18 N.
Abstract: Concrete is strong in compression however weak in
tension. The tensile strength as well as ductile property of concrete
could be improved by addition of short dispersed fibers. Polyethylene
terephthalate (PET) fiber obtained from hand cutting or mechanical
slitting of plastic sheets generally used as discrete reinforcement in
substitution of steel fiber. PET fiber obtained from the former process
is in the form of straight slit sheet pattern that impart weaker
mechanical bonding behavior in the concrete matrix. To improve the
limitation of straight slit sheet fiber the present study considered two
additional geometry of fiber namely (a) flattened end slit sheet and
(b) deformed slit sheet. The mix for plain concrete was design for a
compressive strength of 25 MPa at 28 days curing time with a watercement
ratio of 0.5. Cylindrical and beam specimens with 0.5% fibers
volume fraction and without fibers were cast to investigate the
influence of geometry on the mechanical properties of concrete. The
performance parameters mainly studied include flexural strength,
splitting tensile strength, compressive strength and ultrasonic pulse
velocity (UPV). Test results show that geometry of fiber has a
marginal effect on the workability of concrete. However, it plays a
significant role in achieving a good compressive and tensile strength
of concrete. Further, significant improvement in term of flexural and
energy dissipation capacity were observed from other fibers as
compared to the straight slit sheet pattern. Also, the inclusion of PET
fiber improved the ability in absorbing energy in the post-cracking
state of the specimen as well as no significant porous structures.
Abstract: This paper seeks to assess the implications of
insurance to foreign direct investment inflow in Nigeria. Multiple
linear regression technique and correlation matrix test were employed
to measure the extent to which foreign direct investment was
influenced. The result showed that insurance premium (IP), asset size
of insurance industry (AS), and total investment of the industry (TI)
impacted significantly and positively on foreign direct investment
inflow in Nigeria. There should be effective risk transfer mechanism
and financial intermediation, which gives the investor confidence in
the risk management strength of the host country.
Abstract: Twin steel plates-concrete composite shear walls are
composed of a pair of steel plate layers and a concrete layer
sandwiched between them, which have the characteristics of both
reinforced concrete shear walls and steel plate shear walls. Twin steel
plates-composite shear walls contain very high ultimsate bearing
capacity and ductility, which have great potential to be applied in the
super high-rise buildings and special structures. In this paper, we
analyzed the basic characteristics and stress mechanism of the twin
steel plates-composite shear walls. Specifically, we analyzed the
effects of the steel plate thickness, wall thickness and concrete
strength on the bearing capacity of the twin steel plates-composite
shear walls. The analysis results indicate that: (1) the initial shear
stiffness and ultimate shear-carrying capacity is not significantly
affected by the thickness of concrete wall but by the class of concrete,
(2) both factors significantly impact the shear distribution of the
shear walls in ultimate shear-carrying capacity. The technique of twin
steel plates-composite shear walls has been successfully applied in
the construction of an 88-meter Huge Statue of Buddha located in
Hunan Province, China. The analysis results and engineering
experiences showed that the twin steel plates-composite shear walls
have great potential for future research and applications.
Abstract: In recent years, the use of the aluminum based alloys
in the industry and technology are increasing. Alloying elements in
aluminum have further been improving the strength and stiffness
properties that provide superior compared to other metals. In this
study, investigation of physical properties (microstructure,
microhardness, tensile strength, electrical conductivity and thermal
properties) in the Al-12.6wt.%Si-%2wt.Ni ternary alloy were
investigated. Al-Si-Ni alloy was prepared in vacuum atmosphere. The
samples were directionally solidified upwards with different growth
rate V (8.3−165.45 μm/s) at constant temperature gradient G (7.73
K/mm). The flake spacings (λ), microhardness (HV), ultimate tensile
strength (σ), electrical resistivity (ρ) and thermal properties (H, Cp,
Tm) of the samples were measured. Influence of the growth rate and
spacings on microhardness, ultimate tensile strength and electrical
resistivity were investigated and relationships between them were
obtained. According to results, λ values decrease with increasing V,
but HV, σ and ρ values increase with increasing V. Variations of
electrical resistivity (ρ) of solidified samples were also measured.
The enthalpy of fusion (H) and specific heat (Cp) for the alloy was
also determined by differential scanning calorimeter (DSC) from
heating trace during the transformation from liquid to solid. The
results in this work were compared with the previous similar
experimental results.
Abstract: In this research, thorium dioxide mesoporous
nanocrystalline powder was synthesized through the sol-gel method
using hydrated thorium nitrate and ammonium hydroxide as starting
materials and Triton X100 as surfactant. ThO2 gel was characterized
by thermogravimetric (TGA), and prepared ThO2 powder was
subjected to scanning electron microscopy (SEM), X-ray diffraction
(XRD), and Brunauer-Emett-Teller (BET) analyses studies. Detailed
analyses show that prepared powder consisted of phase with the
space group Fm3m of thoria and its crystalline size was 12.6 nm. The
thoria possesses 16.7 m2/g surface area and the pore volume and size
calculated to be 0.0423 cc/g and 1.947 nm, respectively.