The primary objective of control rod management is to ensure the safe, reliable and
optimum use of the nuclear fuel in the reactor, while remain within the limits imposed
by the design of the fuel assembly and reactor w.r.t the safety analysis. In numerous
reactors, the control rods perform the function of reactivity control, both globally and
locally, latter also control the power distribution of the core. Most control rods are
completely withdrawn from the core during operations and fully inserted during
shutdown of the reactor. This are the prove of an investigative study into optimization
of the heterogeneous control rods, the safety management of an additional safety rod,
and control rod drop hydrodynamic analysis which will be able to provide an efficient
and maximum safety procedure for emergency shut down system in the reactor. It is
also will be very important safety features of the reactor. To design the additional
safety rod at the inner irradiation sites with boron carbide (absorber material) and
stainless steel (clad) and also to design a simple heterogeneous control rod design to
analyse the effects of geometry self-shielding, the Monte Carlo Neutron Particle Code,
version 5 (MCNP5) was used. By simulating the unsteady flow field around the control
rod, the hydrodynamic analysis of the control rod can be analysed. A correlation based
on the achieved data was proposed to provide useful information on the safety
management during the research.
Business strategy plays a key role in determining the success of organizations. In view
of its important role, studies have attempted to investigate the approaches adopted
by organizations to develop as well as implement their business strategy. As far as the
approaches to business strategy are concerned, the review of past studies indicates
that organizations tend to adopt different approaches. At the same time, questions
have been raised as to whether these strategic approaches are relevant and applicable
to all organizations, especially with regard to their emphasis, focus and scope. Based
on the literature, this paper reviews the most common approaches to business
strategy and identifies the differences in their emphasis, focus and scope.
This review paper describes in general the use of VR as a training tool in manufacturing
technology like design, rapid prototyping, and manufacturing with some practical
examples where VR is used and its benefits in manufacturing industries which reduces
a lot of cost in the design stages to the finish stages. VR is the closest man can get to
reality as the names implies with the present capabilities. The technique enables
engineers and designers to move around and interact with the object in real time. This
review paper looks into some challenges of VR applications in manufacturing
industries.
Incineration of both industrial and municipal solid waste has been widely used due to
its ability to reduce the volume of waste by about 90% and detoxify the waste.
However, a great challenge associated with waste incineration is production of toxic
fly and bottom ashes. These ashes contain heavy metals which enters water bodies
through percolation and absorption, and their consequences on human and animals is
enormous. Various researches were conducted on the application of thermal plasma
arc technology to safely detoxify incinerator ashes. The final product from plasma
treatment is a melt or vitreous slag within which toxic heavy metals are cemented. This
paper reviewed the different studies conducted on the treatment of incinerator fly and
bottom ashes in thermal plasma arc reactor. The review looked at the characteristics
of the ashes, the thermal plasma reactor specifications, the operating conditions and
the product characteristics. It also focused on effectiveness of the treatment processes
in terms of volume reduction, detoxification, crystalline structure of the product and
their usability. It is generally observed that thermal plasma arc reactors detoxify both
fly and bottom incinerator ashes, reduce the volume of waste by about 90% and
convert the ash to a vitreous slag where heavy metals are immobilized. Low basicity in
parent ash favours conversion of ash into glassy vitreous slag
A 59-year-old man presented with proximal myopathy, myalgia, and weight loss, with the initial markedly elevated serum creatine kinase at 11,000 U/L. Due to his refusal for muscle biopsy, he was initially treated as inflammatory myositis and responded well with the corticosteroids. However, he subsequently had a relapse of the symptoms with more extensive systemic involvement, i.e., hypercalcemia, lymphadenopathy and subcutaneous nodules. Finally, a biopsy of the thigh and subcutaneous nodule revealed non-caseating granulomatous inflammation, consistent with sarcoidosis. He responded well to the corticosteroids, and finally, azathioprine was added as a steroid-sparing agent. Including our series, there are 103 cases of symptomatic muscle involvement in sarcoidosis patients published in the English literature to date. Further pool analysis of the cases will be reported in this review.
Persistent urogenital sinus (PUGS) is a rare anomaly whereby the urinary and genital tracts fail to separate during embryonic development. We report a three-year-old female child who was referred to the Sabah Women & Children Hospital, Sabah, Malaysia, in 2016 with a pelvic mass. She had been born prematurely at 36 gestational weeks via spontaneous vaginal delivery in 2013 and initially misdiagnosed with neurogenic bladder dysfunction. The external genitalia appeared normal and an initial sonogram and repeat micturating cystourethrograms did not indicate any urogenital anomalies. She therefore underwent clean intermittent catheterisation. Three years later, the diagnosis was corrected following the investigation of a persistent cystic mass posterior to the bladder. At this time, a clinical examination of the perineum showed a single opening into the introitus. Magnetic resonance imaging of the pelvis revealed gross hydrocolpos and a genitogram confirmed a diagnosis of PUGS, for which the patient underwent surgical separation of the urinary and genital tracts.
Cellulose I can be irreversible transformed into cellulose II via mercerisation or regeneration treatments.
In the past few decades, mercerisation was used mainly to improve fibre properties for textile industries.
A few studies have focused on the effects of mercerisation treatment on the cellulose polymorph itself
and after it was downscaled to nanosize. This study aims to characterise the micro size crystalline
cellulose after complete polymorph conversion via mercerisation technique and investigate its effects
on isolation to nanosize crystalline cellulose. A microcrystalline cellulose (MCC) was purchased and
converted into cellulose II via mercerisation technique. Sulphuric acid hydrolysis was carried-out
to produce nanocrystalline cellulose (NCC). The MCC and NCC of different polymorphs were then
characterised and analysed for its crystallography, morphology, particles size distribution and thermal
stability using wide-angle X-ray diffraction (WXRD), electron microscopes, dynamic light scattering
analyser and thermogravimetric analyser, respectively. Both MCC and NCC fibres showed complete
conversion of cellulose I to cellulose II and decrement of crystallinity index (CI). Electron micrographs
revealed that both cellulose II polymorph fibres (MCC II and NCC II) were morphological affected.
The analysis of size distribution and dimension
measurement confirmed that mercerisation
treatment causing increment in fibre diameter and
shortened length. The thermal stability of both
cellulose II polymorph fibres (MCC II and NCC
II) was also found to be improved.
This research investigates the strength of kenaf or epoxy composite filled with mesoporous silica and
studies the hybrid effects between mesoporous silica or kenaf in epoxy matrix. The volume of kenaf
woven mat is maintained constantly at 7.2vol%, whereas proportion of epoxy is varied with inclusion of
mesoporous silica and silicon, keeping constant the volume of the composite at 67.5cm3. The proportion
of mesoporous silica is altered from 0.5vol%, 1.0vol%, 3.0vol% and 5.0vol%, while silicon is kept
constant at 3.0vol%. A total of 11 specimens were produced, each with its distinctive composition and
mechanical strengths. Variation of fillers composition affects the mechanical strengths of the composite.
SEM analysis shows that epoxy bonds well with silicon, kenaf and mesoporous silica. Some de-bonding
among the components is observed within the composite although there is also some tearing of fibres and
impregnation of epoxy within fibre, proving that the components have good interaction and do not act
individually. Flexural test shows that mesoporous silica improves the flexural strength of the composite,
where the highest value is 35.14MPa, obtained at 5.0vol% Mesoporous Silica in Kenaf/Epoxy (SiaK/
Ep). It also improves the flexural modulus, where the highest value is 1569.48MPa, obtained at 3.0vol%
SiaK/Ep. DMA result reveals that adding mesoporous silica increases the Tg of the composite produced.
Highest Tg is obtained at 0.5vol% Mesoporous Silica in Kenaf/Epoxy modofied Silicon (SiaK/Ep-Si)
with the value of 87.54°C.
In the recent years, electronic packaging provides significant research and development challenges
across multiple disciplines such as performance, materials, reliability, thermals and interconnections.
New technologies and techniques frequently adopted can be implemented in soldering alloys of
semiconductor sectors in terms of optimisation. Wetting contact angle or wettability of solder alloys
is one of the important factors which has got the attention of scholars. Hence in this study, due to the
remarkable similarity over classical solder alloys (Pb-Sn), Bi-Ag solder was investigated. Data were
collected through the effects of aging time variation and different weight percentages of Ag in solder
alloys. The contact angle of the alloys with Cu plate was measured by optical microscopy. Artificial
neural networks (ANNs) were applied on the measured datasets to develop a numerical model for further
simulation. Results of the experiments and simulations showed that the coefficient of determination (R2
)
is around 0.97, which signifies that the ANN set up is appropriate for the evaluation.
MeSH terms: Alloys; Attention; Drug Packaging; Electronics; Lead; Microscopy; Semiconductors; Reproducibility of Results; Wettability; Product Packaging
Ridleyandra merohmerea, a new species of Gesneriaceae, is described and illustrated. It is endemic in Peninsular Malaysia and known from a few populations along the Tuang River in the lowland dipterocarp forest of the Ulu Galas Forest Reserve in Kelantan, Peninsular Malaysia. Its conservation status is assessed as Critically Endangered.