Abstract: Large quantities of solid wastes being generated
worldwide from sources such as household, domestic, industrial,
commercial and construction demolition activities, leads to
environmental concerns. Utilization of these wastes in making
building construction materials can reduce the magnitude of the
associated problems. When these waste products are used in place of
other conventional materials, natural resources and energy are
preserved and expensive and/or potentially harmful waste disposal is
avoided. Recycling which is regarded as the third most preferred waste
disposal option, with its numerous environmental benefits, stand as a
viable option to offset the environmental impact associated with the
construction industry. This paper reviews the results of laboratory tests and important
research findings, and the potential of using these wastes in building
construction materials with focus on sustainable development.
Research gaps, which includes; the need to develop standard mix
design for solid waste based building materials; the need to develop
energy efficient method of processing solid waste use in concrete; the
need to study the actual behavior or performance of such building
materials in practical application and the limited real life application
of such building materials have also been identified. A research is being proposed to develop an environmentally
friendly, lightweight building block from recycled waste paper,
without the use of cement, and with properties suitable for use as
walling unit. This proposed research intends to incorporate,
laboratory experimentation and modeling to address the identified
research gaps.
Abstract: In this study, the effects and interactions of reaction
time and capping agent assistance during sol-gel synthesis of
magnesium substituted hydroxyapatite nanopowder (MgHA) on
hydroxyapatite (HA) to β-tricalcium phosphate (β-TCP) ratio, Ca/P
ratio and mean crystallite size was examined experimentally as well
as through statistical analysis. MgHA nanopowders were synthesized
by sol-gel technique at room temperature using aqueous solution of
calcium nitrate tetrahydrate, magnesium nitrate hexahydrate and
potassium dihydrogen phosphate as starting materials. The reaction
time for sol-gel synthesis was varied between 15 to 60 minutes. Two
process routes were followed with and without addition of
triethanolamine (TEA) in the solutions. The elemental compositions
of as-synthesized powders were determined using X-ray fluorescence
(XRF) spectroscopy. The functional groups present in the assynthesized
MgHA nanopowders were established through Fourier
Transform Infrared Spectroscopy (FTIR). The amounts of phases
present, Ca/P ratio and mean crystallite sizes of MgHA nanopowders
were determined using X-ray diffraction (XRD). The HA content in
biphasic mixture of HA and β-TCP and Ca/P ratio in as-synthesized
MgHA nanopowders increased effectively with reaction time of sols
(p0.15, two way ANOVA). The MgHA nanopowders
synthesized with TEA assistance exhibited 14 nm lower crystallite
size (p
Abstract: Response Surface Methods (RSM) provide
statistically validated predictive models that can then be manipulated
for finding optimal process configurations. Variation transmitted to
responses from poorly controlled process factors can be accounted
for by the mathematical technique of propagation of error (POE),
which facilitates ‘finding the flats’ on the surfaces generated by
RSM. The dual response approach to RSM captures the standard
deviation of the output as well as the average. It accounts for
unknown sources of variation. Dual response plus propagation of
error (POE) provides a more useful model of overall response
variation. In our case, we implemented this technique in predicting
compressive strength of concrete of 28 days in age. Since 28 days is
quite time consuming, while it is important to ensure the quality
control process. This paper investigates the potential of using design
of experiments (DOE-RSM) to predict the compressive strength of
concrete at 28th day. Data used for this study was carried out from
experiment schemes at university of Benghazi, civil engineering
department. A total of 114 sets of data were implemented. ACI mix
design method was utilized for the mix design. No admixtures were
used, only the main concrete mix constituents such as cement, coarseaggregate,
fine aggregate and water were utilized in all mixes.
Different mix proportions of the ingredients and different water
cement ratio were used. The proposed mathematical models are
capable of predicting the required concrete compressive strength of
concrete from early ages.
Abstract: In 2009, the new HRM policy was implemented in
Qatar for public sector organisations. The purpose of this research is
to examine how Qatar’s 2009 HRM policy was significant in
influencing employee retention in public organisations. The
conducted study utilised quantitative methodology to analyse the data
on employees’ perceptions of such HRM practices as Performance
Management, Rewards and Promotion, Training and Development
associated with the HRM policy in public organisations in
comparison to semi-private organisations. Employees of seven public
and semi-private organisations filled in the questionnaire based on
the 5-point Likert scale to present quantitative results. The data was
analysed with the correlation and multiple regression statistical
analyses. It was found that Performance Management had the
relationship with Employee Retention, and Rewards and Promotion
influenced Job Satisfaction in public organisations. Relationship
between Job Satisfaction and Employee Retention was also observed.
However, no significant differences were observed in the role of
HRM practices in public and semi-private organisations.
Abstract: Prosecution of sexual violence in international
criminal law requires not only an understanding of the mechanisms
employed to prosecute sexual violence but also a critical analysis of
the factors facilitating perpetuation of such crimes in armed conflicts.
The extrapolations laid out in this essay delve into the jurisprudence
of international criminal law pertaining to sexual and gender based
violence followed by the core question of this essay – has the
entrenchment of sexual violence as international crimes in the Rome
Statute been successful to address such violence in armed conflicts?
Abstract: The purposes of this research are to make comparisons in
respect of the behaviors on the use of the services of metered taxi
classified by the demographic factor and to study the influence of the
recognition on service quality having the effect on usage behaviors of
metered taxi services of consumers in Bangkok Metropolitan Areas. The
samples used in this research were 400 metered taxi service users in
Bangkok Metropolitan Areas and questionnaire was used as the tool for
collecting the data. Analysis statistics are mean and multiple regression
analysis. Results of the research revealed that the consumers recognize the
overall quality of services in each aspect include tangible aspects of the
service, responses to customers, assurance on the confidence,
understanding and knowing of customers which is rated at the moderate
level except the aspect of the assurance on the confidence and
trustworthiness which are rated at a high level. For the result of
hypothetical test, it is found that the quality in providing the services on
the aspect of the assurance given to the customers has the effect on the
usage behaviors of metered taxi services and the aspect of the frequency
on the use of the services per month which in this connection. Such
variable can forecast at one point nine percent (1.9%). In addition, quality
in providing the services and the aspect of the responses to customers
have the effect on the behaviors on the use of metered taxi services on the
aspect of the expenses on the use of services per month which in this
connection, such variable can forecast at two point one percent (2.1%).
Abstract: This paper presents the results of a study on the
influence of varying percentages of rock bridges along a basal surface
defining a biplanar failure mode. A pseudo-coupled-hydromechanical
brittle fracture analysis is adopted using the state-of-the-art code
Slope Model. Model results show that rock bridge failure is strongly
influenced by the incorporation of groundwater pressures. The
models show that groundwater pressure can promote total failure of a
5% rock bridge along the basal surface. Once the percentage of the
rock bridges increases to 10 and 15%, although, the rock bridges are
broken, full interconnection of the surface defining the basal surface
of the biplanar mode does not occur. Increased damage is caused
when the rock bridge is located at the daylighting end of the basal
surface in proximity to the blast damage zone. As expected, some
cracking damage is experienced in the blast damage zone, where
properties representing a good quality controlled damage blast
technique were assumed. Model results indicate the potential increase
of permeability towards the blast damage zone.
Abstract: The end panels of a large rectangular industrial duct,
which experience significant internal pressures, also experience
considerable transverse shear due to transfer of gravity loads to the
supports. The current design practice of such thin plate panels for
shear load is based on methods used for the design of plate girder
webs. The structural arrangements, the loadings and the resulting
behavior associated with the industrial duct end panels are, however,
significantly different from those of the web of a plate girder. The
large aspect ratio of the end panels gives rise to multiple bands of
tension fields, whereas the plate girder web design is based on one
tension field. In addition to shear, the industrial end panels are
subjected to internal pressure which in turn produces significant
membrane action. This paper reports a study which was undertaken
to review the current industrial analysis and design methods and to
propose a comprehensive method of designing industrial duct end
panels for shear resistance. In this investigation, a nonlinear finite element model was
developed to simulate the behavior of industrial duct end panel, along
with the associated edge stiffeners, subjected to transverse shear and
internal pressures. The model considered the geometric imperfections
and constitutive relations for steels. Six scale independent
dimensionless parameters that govern the behavior of such end panel
were identified and were then used in a parametric study. It was
concluded that the plate slenderness dominates the shear strength of
stockier end panels, and whereas, both the plate slenderness and the
aspect ratio influence the shear strength of slender end panels. Based
on these studies, this paper proposes design aids for estimating the
shear strength of rectangular duct end panels.
Abstract: Coal fly ash, an industrial by product of coal
combustion thermal power plants is considered as a hazardous
material and its improper disposal has become an environmental
issue. On the other hand, manufacturing conventional clay bricks
involves on consumption of large amount of clay and leads
substantial depletion of topsoil. This paper unveils the possibility of
using fly ash as a partial replacement of clay for brick manufacturing
considering the local technology practiced in Bangladesh. The effect
of fly ash with different replacing ratio (0%, 20%, 30%, 40%, and
50% by volume) of clay on properties of bricks was studied. Bricks
were made in the field parallel to ordinary bricks marked with
specific number for different percentage to identify them at time of
testing. No physical distortion is observed in fly ash brick after
burning in the kiln. Results from laboratory test show that
compressive strength of brick is decreased with the increase of fly
ash and maximum compressive strength is found to be 19.6 MPa at
20% of fly ash. In addition, water absorption of fly ash brick is
increased with the increase of fly ash. The abrasion value and
Specific gravity of coarse aggregate prepared from brick with fly ash
also studied and the results of this study suggests that 20% fly ash
can be considered as the optimum fly ash content for producing good
quality bricks utilizing present practiced technology.
Abstract: Mechanical behavior of 6082T6 aluminum is
investigated at different temperatures. The strain rate sensitivity is
investigated at different temperatures on the grain size variants. The
sensitivity of the measured grain size variants on 3-D grain is
discussed. It is shown that the strain rate sensitivities are negative for
the grain size variants during the deformation of nanostructured
materials. It is also observed that the strain rate sensitivities vary in
different ways with the equivalent radius, semi minor axis radius,
semi major axis radius and major axis radius. From the obtained
results, it is shown that the variation of strain rate sensitivity with
temperature suggests that the strain rate sensitivity at the low and the
high temperature ends of the 6082T6 aluminum range is different.
The obtained results revealed transition at different temperature from
negative strain rate sensitivity as temperature increased on the grain
size variants.
Abstract: Present empirical paper investigates the relationship
between FDI and economic growth by 10 selected industries in 10
Central and Eastern European countries from the period 1995 to
2012. Different estimation approaches were used to explore the
connection between FDI and economic growth, for example OLS,
RE, FE with and without time dummies. Obtained empirical results
leads to some main consequences: First, the Central and East
European countries (CEEC) attracted foreign direct investment,
which raised the productivity of industries they entered in. It should
be concluded that the linkage between FDI and output growth by
industries is positive and significant enough to suggest that foreign
firm’s participation enhanced the productivity of the industries they
occupied. There had been an endogeneity problem in the regression
and fixed effects estimation approach was used which partially
corrected the regression analysis in order to make the results less
biased. Second, it should be stressed that the results show that time
has an important role in making FDI operational for enhancing output
growth by industries via total factor productivity. Third, R&D
positively affected economic growth and at the same time, it should
take some time for research and development to influence economic
growth. Fourth, the general trends masked crucial differences at the
country level: over the last 20 years, the analysis of the tables and
figures at the country level show that the main recipients of FDI of
the 11 Central and Eastern European countries were Hungary, Poland
and the Czech Republic. The main reason was that these countries
had more open door policies for attracting the FDI. Fifth, according
to the graphical analysis, while Hungary had the highest FDI inflow
in this region, it was not reflected in the GDP growth as much as in
other Central and Eastern European countries.
Abstract: The goal of this paper is to specify factors influencing
the profitability of selected banks. Next, a model will be created to
help establish variables that have a demonstrable influence on the
development of the selected banks' profitability ratios. Czech banks
and their international parent companies were selected for analyzing
profitability. Banks categorized as large banks (according to the
Czech National Bank's system, which ranks banks according to
balance sheet total) were selected to represent the Czech banks. Two
ratios, the return on assets ratio (ROA) and the return on equity ratio
(ROE) are used to assess bank profitability. Six endogenous and four
external indicators were selected from among other factors that
influence bank profitability. The data analyzed were for 2001–2013.
First, correlation analysis, which was supposed to eliminate
correlated values, was conducted. A large number of correlated
values were established on the basis of this analysis. The strongly
correlated values were omitted. Despite this, the subsequent
regression analysis of profitability for the individual banks that were
selected did not confirm that the selected variables influenced their
profitability. The studied factors' influence on bank profitability was
demonstrated only for Ceskoslovenska Obchodni Banka and Société
Générale using regression analysis. For Československa Obchodni
Banka, it was demonstrated that inflation level and the amount of the
central bank's interest rate influenced the return on assets ratio and
that capital adequacy and market concentration influenced the return
on equity ratio for Société Générale.
Abstract: The use of Computer Aided Design (CAD)
technologies has become pervasive in the Architecture, Engineering
and Construction (AEC) industry. This has led to its inclusion as an
important part of the training module in the curriculum for
Architecture Schools in Nigeria. This paper examines the ethical
questions that arise in the implementation of Computer Aided Design
(CAD) Content of the curriculum for Architectural education. Using
existing literature, it begins this scrutiny from the propriety of
inclusion of CAD into the education of the architect and the
obligations of the different stakeholders in the implementation
process. It also examines the questions raised by the negative use of
computing technologies as well as perceived negative influence of
the use of CAD on design creativity. Survey methodology was
employed to gather data from the Department of Architecture,
Chukwuemeka Odumegwu Ojukwu University Uli, which has been
used as a case study on how the issues raised are being addressed.
The paper draws conclusions on what will make for successful ethical
implementation.
Abstract: Thermoacoustic refrigerator is a cooling device which
uses the acoustic waves to produce the cooling effect. The aim of this
paper is to explore the experimental and numerical feasibility of a
standing-wave thermoacoustic refrigerator. The effects of the stack
length, position of stack and operating frequency on the cooling
performance are carried out. The circular pore stacks are tested under
the atmospheric pressure. A low-cost loudspeaker is used as an
acoustic driver. The results show that the location of stack installed in
resonator tube has a greater effect on the cooling performance, than
the stack length and operating frequency, respectively. The
temperature difference across the ends of stack can be generated up
to 13.7°C, and the temperature of cold-end is dropped down by 5.3°C
from the ambient temperature.
Abstract: Considering the challenges of short product life cycles
and growing variant diversity, cost minimization and manufacturing
flexibility increasingly gain importance to maintain a competitive
edge in today’s global and dynamic markets. In this context, an
aerodynamic part feeding system for high-speed industrial assembly
applications has been developed at the Institute of Production
Systems and Logistics (IFA), Leibniz Universitaet Hannover. The
aerodynamic part feeding system outperforms conventional systems
with respect to its process safety, reliability, and operating speed. In
this paper, a multi-objective optimisation of the aerodynamic feeding
system regarding the orientation rate, the feeding velocity, and the
required nozzle pressure is presented.
Abstract: A model to predict the plastic zone size for material
under plane stress condition has been developed and verified
experimentally. The developed model is a function of crack size,
crack angle and material property (dislocation density). Simulation
and validation results show that the model developed show good
agreement with experimental results. Samples of low carbon steel
(0.035%C) with included surface crack angles of 45o, 50o, 60o, 70o
and 90o and crack depths of 2mm and 4mm were subjected to low
strain rate between 0.48 x 10-3 s-1 – 2.38 x 10-3 s-1. The mechanical
properties studied were ductility, tensile strength, modulus of
elasticity, yield strength, yield strain, stress at fracture and fracture
toughness. The experimental study shows that strain rate has no
appreciable effect on the size of plastic zone while crack depth and
crack angle plays an imperative role in determining the size of the
plastic zone of mild steel materials.
Abstract: Concurrent planning of project scheduling and
material ordering has been increasingly addressed within last decades
as an approach to improve the project execution costs. Therefore, we
have taken the problem into consideration in this paper, aiming to
maximize schedules quality robustness, in addition to minimize the
relevant costs. In this regard, a bi-objective mathematical model is
developed to formulate the problem. Moreover, it is possible to
utilize the all-unit discount for materials purchasing. The problem is
then solved by the E-constraint method, and the Pareto front is
obtained for a variety of robustness values. The applicability and
efficiency of the proposed model is tested by different numerical
instances, finally.
Abstract: Poverty alleviation is one of the most difficult
challenges facing third world countries in their development efforts.
Evidences in Nigeria showed that the number of those in poverty has
continued to increase. This paper is aimed at analyzing the
performance of poverty alleviation measures undertaken by
successive administrations in Nigeria with a view to addressing the
quagmire. The study identified the whole gamut of factors that served
as stumbling blocks to the implementation of each of the strategies
and recommended the involvement of local people in the
identification and design of projects so that sufficient participation
could be achieved.
Abstract: The aim of this study is to evaluate the effect of
supplementing broiler starter diet with different levels of an essential
oil blend (EOB) containing capsaicin, carvacrol and cinnamaldehyde
on the performance of broilers. A total of 300 day-old straight-run
Cobb broiler chicks were randomly assigned to three treatments after
7-day group brooding following a completely randomized design
(CRD). Birds assigned in treatment 1 were given starter basal diet
while those in treatments 2 and 3 were given starter basal diet with
400 mg/kg antibiotic growth promoter (AGP) and 150 mg/kg EOB,
respectively, until the 28th day. Basal finisher feed were given for all
the treatments until harvest. Following 37 d feeding, body weight
gain, feed consumption, feed efficiency, dressing percentage,
livability and jejunal villi height were determined. Results showed no
significant differences (P>0.05) in growth performance. However,
villi height and crypt depth was significantly lower for birds fed
EOB.
Abstract: In this paper, we have reported birefringence
manipulation in regenerated high birefringent fiber Bragg grating
(RPMG) by using CO2 laser annealing method. The results indicate
that the birefringence of RPMG remains unchanged after CO2 laser
annealing followed by slow cooling process, but reduced after fast
cooling process (~5.6×10-5). After a series of annealing procedures
with different cooling rates, the obtained results show that slower the
cooling rate, higher the birefringence of RPMG. The volume, thermal
expansion coefficient (TEC) and glass transition temperature (Tg)
change of stress applying part in RPMG during cooling process are
responsible for the birefringence change. Therefore, these findings
are important to the RPMG sensor in high and dynamic temperature
environment. The measuring accuracy, range and sensitivity of
RPMG sensor is greatly affected by its birefringence value. This
work also opens up a new application of CO2 laser for fiber annealing
and birefringence modification.