Older adults are at risk of osteoporotic fractures. Osteoporotic vertebral fractures are associated with a reduced cross-sectional area and muscle strength of the back extensor muscles, increased intramuscular fat infiltration and thoracic and lumbar curvature alterations. This study proposed a protocol to examine in more detail the contributions of altered spinal morphological, physical performance and biochemical markers to the risk of developing osteoporotic vertebral fractures. In this cross-sectional study, we plan to recruit 100 adults aged 50 years and above from an orthopaedic clinic, Hospital Canselor Tuanku Muhriz, Universiti Kebangsaan Malaysia. The fracture prediction tool (FRAX) will be used to categorise high and low risk groups. Back muscle strength will be quantified using a load cell system. Thoracolumbar curvatures will be examined using an electromagnetic tracking system and intramuscular fat infiltration in the lumbar muscles will be measured using Magnetic Resonance Imaging. The Short Physical Performance Battery and JAMA dynamometer will quantify physical performance and the European Quality of Life Questionnaire will be used to assess self-perceived quality of life. Biochemical markers of serum C terminal telopeptide and N terminal propeptide of type I procollagen will be assessed using an enzyme-linked immunosorbent assays kit. A spine-specific model using regression analysis will be developed to predict osteoporotic vertebral fractures using the measured parameters in the present study.
Filters are the basic part in wired, and wireless telecommunications and radar system circuits
and they play an important role in determining the cost and performance of a system. The
increasing demand for high performance in the fields of RF, WLAN, WiMAX and other
wireless communications led to the great revolution in the advancement of the development of
a compact microstrip resonator filter design. All these have made a vital contribution to both
the required performance specifications for filters and other commercial requirements in terms
of low cost, large storage capacity and high-speed performance. This review paper presents
several design examples for multi-band, multi - mode microstrip filter resonators to satisfy RF,
WLAN, WiMAX, UWB and other wireless communication frequency bands. To analyse the
resonant frequencies odd - mode and even -modes can be used for the symmetrical structure.
In general, the multi-mode resonators can be designed by using different methods like crosscoupling
resonators Structure, and the allocation of the fundamental resonant frequencies of
the resonator as stated by the Chebyshev’s insertion loss function.
This paper presents an improved version of a wireless device embedded with a smart PZT sensor to
detect flaws and structural defects on selected investigated structure. Smart PZT sensors were used as an
actuator and sensor, coupled with two XBee’s and one signal generator IC chip. Programme execution on
transmitting and receiving the ultrasonic guided wave via the PZT sensor had been written in MATLAB.
The developed source code is basically to receive serial data from one Xbee to another remote Xbee attached
to the investigated structural system. The refined waveform response is utilised for prognosis of the true
structural status. The 4-mm simulated holed into one of the aluminium structural plate is benchmarked
with its pristine condition in validating the effectiveness of the developed SHM wireless module. Results
showed that the wave is more even in non-defected area and disrupted in affected area. Ultrasonic waves
increase continuously for non-destructive evaluation and structural health monitoring in various structural
applications because the guided wave can propagate long distances and reach difficult-to-access regions;
for inspecting porous and some non-porous materials ultrasonic waves attenuate fast and are very useful.
Recent advances in ultrasonic wave application model and results are discussed in this paper.
All buoyant and hybrid buoyant aerial vehicles have directional stability issues at low speed. Electric
trimmers are one of the potential solutions for controlling the yaw motion of such vehicles in which
partial lift is obtained from the wings. However, available propeller disk area of such trimmers is limited
due to small surface area of the vertical tail. In the present work, maximum input power required by thin
electric propellers with different pitch values are compared to obtain an optimised value of pitch for
propeller selection. Analytical as well as computational techniques are employed to evaluate the moment
generated by tangential thrust produced by a ducted propeller. Motocalc® software under predicts the
thrust value when compared with the computational results under the same flow conditions. The estimated
yaw force produced by the propeller is quite significant and it can also be used for creating differential
thrust using twin electric motors.
This paper presents experimental findings derived from high velocity impact tests on woven-roving Glass
Fibre-Reinforced Polymers (GFRP) Type E-800 g/m² and Type C-600 g/m². The effects on specimen
thickness, projectile shape and gas gun pressure were investigated. As the gas gun pressure increases,
there is a proportional increase in the projectile kinetic energy, the projectile initial velocity, the maximum
force exerted on the specimens and in energy absorption upon impact. During the test, the shape of the
projectile, the target thickness and the gas gun pressure significantly affected the impact performance of
the GFRP. From the experiment, it was found that GFRP Type E-800 g/m² is stronger and more impact
resistant compared with GFRP Type C-600 g/m², due to the fact that E-glass materials have higher fibre
volume and density and overall better mechanical properties than C-glass fibres. Therefore, GFRP Type
E-800 g/m² composites should be considered for applications in load and impact bearing aircraft structures.
Composite structures and materials are used in aerospace, marine and automotive applications due
to their light weight characteristics. By using rice husk ash (RHA) as natural binder to replace epoxy
resin, it improves the characteristic of the composite laminated structure. Rice husk has become an
important ingredient in silica, silicon carbide, and silicon nitride because of its high a silicon content.
This paper evaluates the performance of laminated composite plate in a drop-weight impact testing. Two
plates are attached to the test rig in the particular desired impact orientation. The main advantages of
this process are the plates provide more realistic drop-weight impact and data. Data from the impact test
was collected and analysed to evaluate the material properties of epoxy resin and RHA. Results show
RHA’s energy absorption is better and it has more deformation to prevent structure failures compared
with epoxy resin. This paper aims to evaluate the application of RHA as a geopolymer binder and flax
fibre as an alternative material to glass fibre in the composites industry.
The influence of elevated germanium concentration on the thermoluminesence characteristics of a novel
form of fabricated flat optical fibre was examined. All the samples were irradiated with two nominal
photon energies (6 MV and 10 MV) and 1.25 MeV gamma energy. Flat fibres with 10 mol % Ge
concentration provided the superior TL yield compared against that of 6 and 8 mol % Ge-doped optical
fibres for both 6 MV and 10 MV energy. Interpretation of the results has been aided by study of the glow
curves, revealing in particular new generation of defects in the flat fibres due to strain-generation at the
collapsed surfaces. The strain represent deep-energy defects.
Adnexal masses are growths that form near the uterus; the majority being ovarian tumours. Although
there is no established population-screening tool for detecting ovarian cancer, ultrasound and contrastenhanced
computed tomography (CECT) are useful imaging tools in the management of adnexal masses.
Our study aimed to determine the characteristics of malignant adnexal masses on CECT scan and to
describe common pitfalls in diagnosis of ovarian cancer when interpreting images. We also determined the
sensitivity and specificity of diagnosing ovarian cancer using CECT. A retrospective study was conducted
in Hospital Serdang using data from all patients who underwent CECT scan and detected with adnexal
masses, and had histopathological examination correlation from January 2013 until January 2015. Out of
the 64 cases analysed; the majority of malignant lesions were serous carcinoma of the ovary (40%). The
CECT scan characteristics, tumour consistency of mixed type, presence of wall enhancement, septations,
ascites and peritoneal nodule/omental caking were significantly associated with ovarian malignancy
(p
The use of prenatal ultrasound has become controversial as it is increasingly being performed for business
and social interests rather than for medical use. This nonmedical use of the modality has violated the
US FDA guideline. Ultrasound scans have been proven to increase temperature in insonated tissue and
their effects have been investigated via phantom and animal experiments. Absorption coefficient of the
bone is the highest compared with any other structure. Thus, exposure to ultrasound, especially during
osteogenesis, can cause significant damage to developing foetus. Twenty-two pregnant does of known
gestation were enrolled in the control and experimental groups. No exposure was given to the control
group while the experimental groups were exposed accordingly to the prenatal ultrasound in the 1st,
2nd and 3rd stage for 30, 60 and 90 minutes respectively. A total of 142 subjects aged between 1 and 5
months were analysed for bone strength. The Tb.Th of the experimental group was reduced significantly
as compared to the control group. Po, TMD and empty lacunae were higher in the experimental group.
It is thus concluded that one-time prenatal ultrasound can affect bone strength in young subjects.
Popliteal artery injury is the most disastrous intraoperative complication during total knee replacement. This study aims to determine the mean distance between the popliteal artery (PA) and the tibial plateau in normal and osteoarthritic patients who underwent Dual Energy CT Angiography (CTA) of the lower limb.
Materials and Methods: All CTA lower limb examinations from January 2013 to October 2014 were retrospectively reviewed. The distance between the PA the tibial plateau distance and the thickness of popliteus muscle were electronically measured. We used modified Kellgren and Lawrence’s Classification to grade the osteoarthritis in patients who underwent CT examinations regardless of symptoms.
Results: There were a total of 126 patients who underwent CTA (93 males and 33 females). 54 of them were Malays, 47 Indians, and 24 Chinese. The mean age of patients was 58 years (range 16 to 92). The mean PA-totibial plateau distance was 9.9 mm for the right lower limb (range 2.5 mm to 17.2 mm) and 10.24 mm for the left (range 5.5 mm to 15.4 mm). There were no significant correlations between PA-to-tibial plateau distance with osteoarthritis grade, age, gender, and racial origin (P > 0.05); however, there was a positive
correlation between PA-to-tibial plateau distances with popliteus muscle thickness (P = 0.000).
Conclusion: Osteoarthritic condition in the knee does not reduce the popliteal artery to the tibial plateau distance. Hence, a higher osteoarthritic grade does not impose additional risks with regards to popliteal artery to tibial plateau distance, with relatively similar arterial injury risks compared to normal knees.
Understanding rainfall trend can be a first step in the planning and management of water resources
especially at the basin scale. In this study, standard tests are used to examine rainfall trends based on monthly, seasonal and mean annual series at the Niger-South Basin, Nigeria, between 1948 and 2008. Rainfall variability index showed that the decade 2000s was the driest (-2.1), while 1950s was the wettest (+0.8), with the decade 1980s being the driest in the second half of the last century, whereas the year 1983 was the driest throughout the series. Over the entire basin, rainfall variability was generally low, but higher intra-monthly than inter-annually. Annual rainfall was dominated by August, contributing about 15%, while December contributed the least (0.7%). On a seasonal scale, July-August-September (JJA) contributed over 40% of the annual rainfall, while rainfall was lowest during December-January-February (DJF) (4.5%). The entire basin displayed negative trends but only 15% indicated significant changes (α ‹ 0.1), while the magnitudes of change varied between -3.75 and -0.25 mm/yr. Similarly, only JJA exhibited insignificant upward trend, while the rest showed negative trends. About eight months of the year showed reducing trends, but only January trend was significant. Annual downward trend was generally observed in the series. The trend during 1948–1977 was negative, but it was positive for the 1978–2008 period. Hence, water resources management planning may require construction of water storage facilities to reduce summer flooding and prevent possible future water scarcity in the basin.
Soluble solid content (SSC) is one of the important traits that indicate the ripeness of banana fruits.
Determination of SSC for banana often requires destructive laboratory analysis on the fruit. An impedance measurement technique was investigated as a non-destructive approach for SSC determination of bananas. A pair of electrocardiogram (ECG) electrode connected to an impedance analyser board was used to measure the impedance value of bananas over the frequency of 19.5 to 20.5 KHz. The SSC measurement was conducted using a pocket refractometer and data was analysed to correlate SSC with impedance values. It was found that the mean of impedance, Z decreased from 10.01 to 99.93 KΩ at the frequency of 20 KHz, while the mean value of SSC increased from 0.58 to 4.93 % Brix from day 1 to day 8. The best correlation between impedance and SSC was found at 20 KHz, with the coefficient of determination, R2 of 0.87. This result indicates the potential of impedance measurement in predicting SSC of banana fruits.
This paper introduces new forms of bivariate generalized Poisson (BGP) and bivariate negative binomial (BNB) regression models which can be fitted to bivariate and correlated count data with covariates. The BGP and BNB regression models can be fitted to bivariate count data with positive, zero or negative correlations. Applications of new BGP and BNB regression models are illustrated on Australian health survey data.
The transformation method (TM) of fuzzy arithmetic is aimed at simulation and analysis of a system. The aim of this paper is to use fuzzy arithmetic based on the TM on a state space of a steam turbine system. The model is then used to identify the degree of influence of each parameter on the system. Simulation and analysis of the system are presented in this paper.
Fuzzy set with similarity measure approaches are known to be effective in handling imprecise and
subjective information to solve decision making problems. Many methods have been introduced based on these two concepts. However, most methods do not take into account the reliability factor of the imprecise information in the evaluation process. In 2010, Zadeh coined the idea of Z-number that has the ability to consider the reliability factor or the level of confidence of human’s information expression. Since then, some decision-making methods have included this concept. In this paper, we present a new fuzzy decision making procedure by integrating the Jaccard similarity measure with Z-number to solve a multi criteria decision making problem. The conversion method of the Z-number based linguistic value to trapezoidal fuzzy numbers is used and the Jaccard similarity measure of the expected intervals of trapezoidal fuzzy numbers is applied to obtain the final decision. The feasibility of the methodology is demonstrated by investigating the preference factors that could influence customers to buy their preferred choice of car. The proposed methodology is applicable to solving decision making with a fuzzy environment to achieve a reliable and optimal decision.
Palm Oil Fuel Ash (POFA) is a biomass produced from palm oil industries. POFA is known to contain
a high amount of silica and has been proven by XRF spectroscopy, in which the silicon dioxide content
is 72.63%. In this study, silica was synthesised from POFA. To extract the silica, POFA was fused
with alkaline agent (Na2CO3) before mixing with Cethyltrimetyl Ammonium Bromide (CTAB) and
Sulphuric Acid (H2SO4). Sodium silicate solution from the fusion was used as silica precursor replacing
conventionally used silica source, Tetraethoxilane (TEOS). XRD pattern showed that raw POFA
dominantly consists of silica. Meanwhile, FTIR analysis of the synthesised silica exhibited spectra
bands at 3393 cm-1, 1635 cm-1, 1028 cm-1 and 787 cm-1 that corresponded to the functional groups of
Si-O and O-H. Thus, it could be concluded that silica was successfully extracted from POFA by the
alkaline fusion method.
Pedestrian level in the urban area is an important area where most of pedestrians’ activities occur at this
level. Therefore, the purpose of this study is to investigate effects of various building layouts on mean
wind speed ratio at the pedestrian level. The mean wind speed ratio at the pedestrian level was analysed
in order to determine whether the building layouts configured within this research are able to enhance
outdoor ventilation and ensure good pedestrian comfort level. The simulation model consists of two main
areas which are the upstream area and downstream area with a setback distance, d. The building layouts
at upstream area are arranged in staggered arrangements (ST) or square arrangements (SQ), while the
downstream areas are in a fixed staggered arrangement (ST). Packing density in both areas is 25% with
three setback distances which are 3H, 5H and 7H. Based on the results, the mean wind speed ratio at the
pedestrian level in a downstream area with longer setback distance will provide a higher mean speed ratio,
and the influence of upstream building arrangements on the mean wind speed ratio of the downstream
area decreases as the setback distance increases. Hence, the mean wind speed ratio of downstream area
depends on the setback distance between the upstream and downstream areas.
Self-similarity network traffic is considered as one of stochastic process studies in telecommunications
engineering. In determining self-similarity traffic, Hurst value is an important parameter to be measured.
This paper presents self-similarity traffic measurement using Rescaled Range, R/S statistical method in
estimating Hurst parameter value. Inbound internet traffics on an IP-based campus network in Malaysia,
which implements a 16.0 Mbps speed to internet and supports 10GE bandwidth at switch level, are
captured and measured. The objectives of this research are to observe and present the existence level of
Hurst parameter value, type of self-similarity and overall percentage of Hurts parameter estimation. The
inbound traffic is measured due to its relevancy to next development on policing and shaping algorithm
traffic model. Solarwinds Net Flow machine is setup on a campus gateway to its Wide Area Network
(WAN). Data of the traffic like in flow, size and speed were taken over 20 days and 14 weeks in different
inter-arrival time. These traffics are analysed, which lead to the impacts of packet loss, throughput and
speed in network performance. Results present the Hurst parameter value, the existence of Long Range
Dependant Self-similarity traffic distribution and percentage level of Hurst parameter value for the three
types of captured traffic
Implementation of Trivial File Transfer Protocol (TFTP) in embedded system is significant because of the
speed and simplicity. However, no security service in TFTP marks its major limitations. In this work, a
pre-shared Diffie Hellman Key Exchange (DHKE) technique was proposed for mutual authentication to
achieve the same secret key in TFTP communication protocol. We also integrated the system with feasible
compression and encryption process to significantly improve the TFTP communication performance.
The DHKE proof of concept is discussed briefly to show the feasibility of the pre-shared technique
on the protocol. Also, the experiment was performed on constrained embedded devices to analyse the
performance of compression/encryption scheme in TFTP. From the results obtained, the combined
encryption and compression process is able to reduce the time by about 30% compared to the original
file transmission time. Thus, the proposed work presents both advantages to reduce file size and provide
security for the data. This is a preliminary work to provide a secure T
This study was carried out to investigate effects of acoustic and thermofluid performance of a RanqueHilsch
Vortex Tube (RHVT) with different numbers of swirl generator nozzles. The number of nozzle
used in the experiment was 1, 2, 3, 4, 5 and 6 nozzle(s), respectively. Sound signal produced by the device
was recorded using two microphones located at hot side and cold side of the tube. The sound signal
was transformed using Fast-Fourier Transform (FFT) to obtain the frequency representation. Then, the
frequencies produced were related to its themofluid performance of each configuration.