Abstract: The purpose of this study is to identify human walking vertical force by using FFT power spectrum density from the experimental acceleration data of the human body. An experiment on human walking is carried out on a stationary floor especially paying attention to higher components of dynamic vertical walking force. Based on measured acceleration data of the human lumbar part, not only in-phase component with frequency of 2fw, 3fw, but also in-opposite-phase component with frequency of 0.5 fw, 1.5 fw, 2.5 fw where fw is the walking rate is observed. The vertical vibration of pedestrian bridge induced by higher components of human walking vertical force is also discussed in this paper. A full scale measurement for the existing pedestrian bridge with center span length of 33 m is carried out focusing on the resonance phenomenon due to higher components of human walking vertical force. Dynamic response characteristics excited by these vertical higher components of human walking are revealed from the dynamic design viewpoint of pedestrian bridge.
Abstract: Effect of alloying on the microstructure and mechanical properties of heat-resisting duplex stainless steel (DSS) for Mg production was investigated in this study. 25Cr-8Ni based DSS’s were cast into rectangular ingots of which the dimension was 350×350×100 mm3 . Nitrogen and Yttrium were added in the range within 0.3 in weight percent. Phase equilibrium was calculated using the FactSage®, thermodynamic software. Hot exposure, high temperature tensile and compression tests were conducted on the ingots at 1230oC, which is operation temperature employed for Mg production by Silico-thermic reduction. The steel with N and Y showed much higher strength than 310S alloy in both tensile and compression tests. By thermal exposition at 1230oC for 200 hrs, hardness of DSS containing N and Y was found to increase. Hot workability of the heat-resisting DSS was evaluated by employing hot rolling at 1230 oC. Hot shortness was observed in the ingot with N and found to disappear after addition of Y.
Abstract: This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.
Abstract: The world crude oil demand is projected to rise to 108.5 million bbl/d by the year 2035. With reserves estimated at 869 billion tonnes worldwide, coal remains an abundant resource. The aim of this work was to produce a high value hydrocarbon liquid product using a Direct Coal Liquefaction (DCL) process at, relatively mild operating conditions. Via hydrogenation, the temperature-staged approach was investigated in a dual reactor lab-scale pilot plant facility. The objectives included maximising thermal dissolution of the coal in the presence of tetralin as the hydrogen donor solvent in the first stage with 2:1 and 3:1 solvent: coal ratios. Subsequently, in the second stage, hydrogen saturation, in particular, hydrodesulphurization (HDS) performance was assessed. Two commercial hydrotreating catalysts were investigated viz. NickelMolybdenum (Ni-Mo) and Cobalt-Molybdenum (Co-Mo). GC-MS results identified 77 compounds and various functional groups present in the first and second stage liquid product. In the first stage 3:1 ratios and liquid product yields catalysed by magnetite were favoured. The second stage product distribution showed an increase in the BTX (Benzene, Toluene, Xylene) quality of the liquid product, branched chain alkanes and a reduction in the sulphur concentration. As an HDS performer and selectivity to the production of long and branched chain alkanes, Ni-Mo had an improved performance over Co-Mo. Co-Mo is selective to a higher concentration of cyclohexane. For 16 days on stream each, Ni-Mo had a higher activity than Co-Mo. The potential to cover the demand for low–sulphur, crude diesel and solvents from the production of high value hydrocarbon liquid in the said process, is thus demonstrated.
Abstract: The conventional ceramic route was utilized to
prepare a hard magnetic powder (M-type strontium ferrite,
SrFe12O19). The stoichiometric mixture of iron oxide and strontium
carbonate were calcined at 1000oC and then fired at various
temperatures. The influence of various reaction parameters such as
mixing ratio, calcination temperature, firing temperature and firing
time on the magnetic behaviors of the synthesized magnetic powder
were investigated. The magnetic properties including Coercivity
(Hc), Magnetic saturation (Ms), and Magnetic remnance (Mr) were
measured by vibrating sample magnetometer. Morphologically the
produced magnetic powder has a dense hexagonal grain shape
structure.
Abstract: A teeming set of doctors that graduated from various
universities within and outside Nigeria with the hope of practicing in
the country, has their hope shattered because of poor financing, lack
of medical equipments and a very weak healthcare systems. Such
hydra headed challenges, allows room for quackery which
increasingly contributes to the cause of mortality in Nigeria. With a
view of reversing the challenges of healthcare delivery and financing
in Nigeria, African Health Market for Equity (AHME), a project
funded by the Bill and Melinda Gates foundation [With contribution
from Department For International Development (DFID)] and
currently implemented in three African Countries (Nigeria, Kenya
and Ghana) over a Five (5) year period supports the healthcare sector
via Medical credit fund (MCF). The study examines the impact of
credit policy and medical credit funding on Nigerian health market.
Ordinary least square analysis, correlation and granger causality tests
were employed to measure the extent to which the Nigerian
healthcare market has been influenced. Medical credit fund
significantly and positively influenced average monthly turnover of
private healthcare providers and Commercial bank’s lending rate had
a weak relationship with access to credit/approved loans (13.46%).
The programme has so far made 13.91% progress, which is very
poor, considering the minimum targeted private health care providers
(437.6) and expected number of loan approvals (180.4) for the two
years. Medical credit policy in Nigeria should be revised to include
private healthcare providers in rural area for more positive impact
and increased returns. Good brand advert and sensitization of the
programme to stakeholders and health pressure group, and an
extension of the programme beyond five years is necessary to better
address the issues raised in the study.
Abstract: Second generation military Filipino Amerasians
comprise a formidable contemporary segment of the estimated
250,000-plus biracial Amerasians in the Philippines today. Overall,
they are a stigmatized and socioeconomically marginalized diaspora;
historically, they were abandoned or estranged by U.S. military
personnel fathers assigned during the century-long Colonial, Post-
World War II and Cold War Era of permanent military basing (1898-
1992). Indeed, U.S. military personnel are assigned in smaller
numbers in the Philippines today. This inquiry is an outgrowth of two
recent small sample studies. The first surfaced the impact of the U.S.
military prostitution system on formation of the ‘Derivative
Amerasian Family Construct’ on first generation Amerasians; a
second, qualitative case study suggested the continued effect of the
prostitution systems' destructive impetuous on second generation
Amerasians. The intent of this current qualitative, multiple-case study
was to actively seek out second generation sex industry toilers. The
purpose was to focus further on this human phenomenon in the postbasing
and post-military prostitution system eras. As background, the
former military prostitution apparatus has transformed into a modern
dynamic of rampant sex tourism and prostitution nationwide. This is
characterized by hotel and resorts offering unrestricted carnal access,
urban and provincial brothels (casas), discos, bars and pickup clubs,
massage parlors, local barrio karaoke bars and street prostitution. A
small case study sample (N = 4) of female and male second
generation Amerasians were selected. Sample formation employed a
non-probability ‘snowball’ technique drawing respondents from the
notorious Angeles, Metro Manila, Olongapo City ‘AMO Amerasian
Triangle’ where most former U.S. military installations were sited
and modern sex tourism thrives. A six-month study and analysis of
in-depth interviews of female and male sex laborers, their families
and peers revealed a litany of disturbing, and troublesome
experiences. Results showed profiles of debilitating human poverty,
history of family disorganization, stigmatization, social
marginalization and the ghost of the military prostitution system and
its harmful legacy on Amerasian family units. Emerging were testimonials of wayward young people ensnared in a maelstrom of
deep economic deprivation, familial dysfunction, psychological
desperation and societal indifference. The paper recommends that
more study is needed and implications of unstudied psychosocial and
socioeconomic experiences of distressed younger generations of
military Amerasians require specific research. Heretofore apathetic or
disengaged U.S. institutions need to confront the issue and formulate
activist and solution-oriented social welfare, human services and
immigration easement policies and alternatives. These institutions
specifically include academic and social science research agencies,
corporate foundations, the U.S. Congress, and Departments of State,
Defense and Health and Human Services, and Homeland Security
(i.e. Citizen and Immigration Services) It is them who continue to
endorse a laissez-faire policy of non-involvement over the entire
Filipino Amerasian question. Such apathy, the paper concludes,
relegates this consequential but neglected blood progeny to the status
of humiliating destitution and exploitation. Amerasians; thus, remain
entrapped in their former colonial, and neo-colonial habitat.
Ironically, they are unwitting victims of a U.S. American homeland
that fancies itself geo-politically as a strong and strategic military
treaty ally of the Philippines in the Western Pacific.
Abstract: In this paper, temperature extremes are forecast by
employing the block maxima method of the Generalized extreme
value(GEV) distribution to analyse temperature data from the
Cameroon Development Corporation (C.D.C). By considering two sets
of data (Raw data and simulated data) and two (stationary and
non-stationary) models of the GEV distribution, return levels analysis
is carried out and it was found that in the stationary model, the
return values are constant over time with the raw data while in the
simulated data, the return values show an increasing trend but with
an upper bound. In the non-stationary model, the return levels of
both the raw data and simulated data show an increasing trend but
with an upper bound. This clearly shows that temperatures in the
tropics even-though show a sign of increasing in the future, there
is a maximum temperature at which there is no exceedence. The
results of this paper are very vital in Agricultural and Environmental
research.
Abstract: Review of studies carried out on the use of bagasse
ash for the improvement of deficient soils in Nigeria, with emphasis
on lateritic and black cotton soils is presented. Although, the bagasse
ash is mostly used as additive to the conventional soil stabilizers
(cement and lime), the studies generally showed improvement in the
geotechnical properties of the soils, either modified or stabilized with
the ash. This showed the potentials of using this agricultural waste
(bagasse ash) in the improvement of geotechnical properties of
deficient soils, thus suggesting that using this material at large scale
level in geotechnical engineering practice could help in the provision
of stable and durable structures, reduce cost of soil improvement and
also reduces environmental nuisance caused by the unused waste in
Nigeria.
Abstract: The purpose of this research was to investigate the
creep behaviour of the heterogeneous Timber-UHPFRC beams. New
developments have been done to further improve the structural
performance, such as strengthening of the timber (glulam) beam by
bonding composite material combine with an ultra-high performance
fibre reinforced concrete (UHPFRC) internally reinforced with or
without carbon fibre reinforced polymer (CFRP) bars. However, in
the design of wooden structures, in addition to the criteria of
strengthening and stiffness, deformability due to the creep of wood,
especially in horizontal elements, is also a design criterion. Glulam,
UHPFRC and CFRP may be an interesting composite mix to respond
to the issue of creep behaviour of composite structures made of
different materials with different rheological properties. In this paper,
we describe an experimental and analytical investigation of the creep
performance of the glulam-UHPFRC-CFRP beams assembled by
bonding. The experimental investigations creep behaviour was
conducted for different environments: in- and outside under constant
loading for approximately a year. The measured results are compared
with numerical ones obtained by an analytical model. This model was
developed to predict the creep response of the glulam-UHPFRCCFRP
beams based on the creep characteristics of the individual
components. The results show that heterogeneous glulam-UHPFRC
beams provide an improvement in both the strengthening and
stiffness, and can also effectively reduce the creep deflection of
wooden beams.
Abstract: In this paper, synchronization of multiple chaotic
semiconductor lasers is achieved by appealing to complex system
theory. In particular, we consider dynamical networks composed by
semiconductor laser, as interconnected nodes, where the interaction
in the networks are defined by coupling the first state of each node.
An interest case is synchronized with master-slave configuration in
star topology. Nodes of these networks are modeled for the laser and
simulate by Matlab. These results are applicable to private
communication.
Abstract: Measuring the Electrocardiogram (ECG) signal is an
essential process for the diagnosis of the heart diseases. The ECG
signal has the information of the degree of how much the heart
performs its functions. In medical diagnosis and treatment systems,
Decision Support Systems processing the ECG signal are being
developed for the use of clinicians while medical examination. In this
study, a modular wireless ECG (WECG) measuring and recording
system using a single board computer and e-Health sensor platform
is developed. In this designed modular system, after the ECG signal
is taken from the body surface by the electrodes first, it is filtered and
converted to digital form. Then, it is recorded to the health database
using Wi-Fi communication technology. The real time access of the
ECG data is provided through the internet utilizing the developed
web interface.
Abstract: This paper presents the interface ConductHome which
controls home automation systems with a Leap Motion using
“invariant gesture protocols”. This interface is meant to simplify the
interaction of the user with its environment. A hardware part allows
the Leap Motion to be carried around the house. A software part
interacts with the home automation box and displays the useful
information for the user. An objective of this work is the
development of a natural/invariant/simple gesture control interface to
help elder people/people with disabilities.
Abstract: The effect of carbon nanofibers (CNFs) on the
electrical properties of Poly(vinylidene fluoride-hexafluoropropylene)
(P(VdF-HFP)) based gel polymer electrolytes has been investigated
in the present work. The length and diameter ranges of CNFs used in
the present work are 5-50 μm and 200-600 nm respectively. The
nanocomposite gel polymer electrolytes have been synthesized by
solution casting technique with varying CNFs content in terms of
weight percentage. Electrochemical impedance analysis demonstrates
that the reinforcement of carbon nanofibers significantly enhances the
ionic conductivity of the polymer electrolyte. The decrease of
crystallinity of P(VdF-HFP) due the addition of CNFs has been
confirmed by X-ray diffraction (XRD). The interaction of CNFs with
various constituents of nanocomposite gel polymer electrolytes has
been assessed by Fourier Transform Infrared (FTIR) spectroscopy.
Moreover CNFs added gel polymer electrolytes offer superior
thermal stability as compared to that of CNFs free electrolytes as
confirmed by Thermogravimetric analysis (TGA).
Abstract: The availability to deploy mobile applications for
health care is increasing daily thru different mobile app stores. But
within these capabilities the number of hacking attacks has also
increased, in particular into medical mobile applications. The security
vulnerabilities in medical mobile apps can be triggered by errors in
code, incorrect logic, poor design, among other parameters. This is
usually used by malicious attackers to steal or modify the users’
information. The aim of this research is to analyze the vulnerabilities
detected in mobile medical apps according to risk factor standards
defined by OWASP in 2014.
Abstract: This paper considers the design of Dual Proportional-
Integral (DPI) Load Frequency Control (LFC), using gravitational
search algorithm (GSA). The design is carried out for nonlinear
hydrothermal power system where generation rate constraint (GRC)
and governor dead band are considered. Furthermore, time delays
imposed by governor-turbine, thermodynamic process, and
communication channels are investigated. GSA is utilized to search
for optimal controller parameters by minimizing a time-domain based
objective function. GSA-based DPI has been compared to Ziegler-
Nichols based PI, and Genetic Algorithm (GA) based PI controllers
in order to demonstrate the superior efficiency of the proposed
design. Simulation results are carried for a wide range of operating
conditions and system parameters variations.
Abstract: Carefully scheduling the operations of pumps can be
resulted to significant energy savings. Schedules can be defined
either implicit, in terms of other elements of the network such as tank
levels, or explicit by specifying the time during which each pump is
on/off. In this study, two new explicit representations based on timecontrolled
triggers were analyzed, where the maximum number of
pump switches was established beforehand, and the schedule may
contain fewer switches than the maximum. The optimal operation of
pumping stations was determined using a Jumping Particle Swarm
Optimization (JPSO) algorithm to achieve the minimum energy cost.
The model integrates JPSO optimizer and EPANET hydraulic
network solver. The optimal pump operation schedule of VanZyl
water distribution system was determined using the proposed model
and compared with those from Genetic and Ant Colony algorithms.
The results indicate that the proposed model utilizing the JPSO
algorithm is a versatile management model for the operation of realworld
water distribution system.
Abstract: The moisture content of densified biomass is a
limiting parameter influencing the quality of this solid biofuel. It
influences its calorific value, density, mechanical strength and
dimensional stability as well as affecting its production process. This
paper deals with experimental research into the effect of moisture
content of the densified material on the final quality of biofuel in the
form of logs (briquettes or pellets). Experiments based on the singleaxis
densification of the spruce sawdust were carried out with a
hydraulic piston press (piston and die), where the densified logs were
produced at room temperature. The effect of moisture content on the
qualitative properties of the logs, including density, change of
moisture, expansion and physical changes, and compressive and
impact resistance were studied. The results show the moisture ranges
required for producing good-quality logs. The experiments were
evaluated and the moisture content of the tested material was
optimized to achieve the optimum value for the best quality of the
solid biofuel. The dense logs also have high-energy content per unit
volume. The research results could be used to develop and optimize
industrial technologies and machinery for biomass densification to
achieve high quality solid biofuel.
Abstract: Healthcare safety has been perceived important. It is
essential to prevent troubles in healthcare processes for healthcare
safety. Trouble prevention is based on trouble prediction using
accumulated knowledge on processes, troubles, and countermeasures.
However, information on troubles has not been accumulated in
hospitals in the appropriate structure, and it has not been utilized
effectively to prevent troubles. In the previous study, however a
detailed knowledge acquisition process for trouble prediction was
proposed, the knowledgebase for countermeasures was not involved.
In this paper, we aim to propose the structure of the knowledgebase for
countermeasures, in the knowledge acquisition process for trouble
prediction in healthcare process. We first design the structure of
countermeasures and propose the knowledge representation form on
countermeasures. Then, we evaluate the validity of the proposal, by
applying it into an actual hospital.
Abstract: The current study aims to highlight the loading
characteristics impact on the time evolution (focusing particularly on
long term effects) of the deformation of realized reinforced concrete
beams. Namely the tension stiffening code provisions (i.e. within
Eurocode 2) are reviewed with a clear intention to reassess their
operational value and predicting capacity. In what follows the
experimental programme adopted along with some preliminary
findings and numerical modeling attempts are presented. For a range of long slender reinforced concrete simply supported
beams (4200 mm) constant static sustained and repeated cyclic
loadings were applied mapping the time evolution of deformation.
All experiments were carried out at the Heavy Structures Lab of the
University of Leeds. During tests the mid-span deflection, creep
coefficient and shrinkage strains were monitored for duration of 90
days. The obtained results are set against the values predicted by
Eurocode 2 and the tools within an FE commercial package (i.e.
Midas FEA) to yield that existing knowledge and practise is at times
over-conservative.