Abstract: The present research study focuses on the investigation of the influence of sand blasting on formed mild steel samples. The investigation involved the examinations on the parent material and a sand blasted material. The results were compared to the mechanically formed materials (sand and non-sand blasted) as well as a laser formed material (sand and non-sand blasted). Each material was characterized for the grain sizes and hardness. The percentage change in the grain sizes was quantified and correlation to the microhardness values was established. The Ultimate Tensile Strength (UTS) of the materials was also quantified using the obtained hardness values. The investigations revealed that the sand blasting causes an increase in the Vickers microhardness values of all the materials which also led to an increase in the UTS. After the forming operation, the microstructure revealed elongated grains as compared to almost equiaxed obtained from the parent non-sand blasted materials.
Abstract: Poverty is a multi-facet phenomenon in today’s globalised world. It is rooted in various causes and there are also multiple ways to do away with it. This paper begins with a review on the definitions and measurement of poverty and followed by discussing the various causes of poverty. This paper specifically identifies corruption, education, political instability, geographical characteristics, ineffective local governance and government policies as the causes of poverty. It then suggests possible solutions or recommendations to eradicate poverty based on the causes discussed earlier. Some of the suggestions include strengthening democratic transparency and government budget transparency, public awareness, creation of a framework for economic growth and transformation, and ways to increase the ability of the poor to raise their income.
Abstract: This article aims to investigate the performance of a magnetic fluid based squeeze film between rotating transversely rough curved porous annular plates incorporating the effect of elastic deformation. The associated stochastically averaged Reynolds type equation is solved to obtain the pressure distribution leading to the calculation of the load carrying capacity. The results suggest that the transverse roughness of the bearing surfaces affects the performance adversely although the bearing systems register a relatively improved performance due to the magnetization. The deformation causes reduced the load carrying capacity while the curvature parameters tend to nominally increase the load carrying capacity. Besides, the adverse effect of porosity, deformation and standard deviation can be minimized to some extent by the positive effect of the magnetization and the curvature parameters in the case of negatively skewed roughness by suitably choosing the rotational inertia and the aspect ratio, which becomes significant when negative variance occurs.
Abstract: An experimental study of the turbulent near wake of a rotating circular cylinder was made at a Reynolds number of 2000 for velocity ratios, λ between 0 and 2.7. Particle image velocimetry data are analyzed to study the effects of rotation on the flow structures behind the cylinder. The results indicate that the rotation of the cylinder causes significant changes in the vortex formation. Kármán vortex shedding pattern of alternating vortices gives rise to strong periodic fluctuations of a vortex street for λ < 2.0. Alternate vortex shedding is weak and close to being suppressed at λ = 2.0 resulting a distorted street with vortices of alternating sense subsequently being found on opposite sides. Only part of the circulation is shed due to the interference in the separation point, mixing in the base region, re-attachment, and vortex cut-off phenomenon. Alternating vortex shedding pattern diminishes and completely disappears when the velocity ratio is 2.7. The shed vortices are insignificant in size and forming a single line of vortex street. It is clear that flow asymmetries will deteriorate vortex shedding, and when the asymmetries are large enough, total inhibition of a periodic street occurs.
Abstract: Power quality is used to describe the degree of consistency of electrical energy expected from generation source to point of use. The term power quality refers to a wide variety of electromagnetic phenomena that characterize the voltage and current at a given time and at a given location on the power system. Power quality problems can be defined as problem that results in failure of customer equipments, which manifests itself as an economic burden to users, or produces negative impacts on the environment. Voltage stability, power factor, harmonics pollution, reactive power and load unbalance are some of the factors that affect the consistency or the quality level. This research proposal proposes to investigate and analyze the causes and effects of power quality to homes and industries in Sarawak. The increasing application of electronics equipment used in the industries and homes has caused a big impact on the power quality. Many electrical devices are now interconnected to the power network and it can be observed that if the power quality of the network is good, then any loads connected to it will run smoothly and efficiently. On the other hand, if the power quality of the network is bad, then loads connected to it will fail or may cause damage to the equipments and reduced its lifetime. The outcome of this research will enable better and novel solutions of poor power quality to small industries and reduce damage of electrical devices and products in the industries.
Abstract: Typhoid fever is a communicable disease, found only in man and occurs due to systemic infection mainly by Salmonella typhi organism. The disease is endemic in many developing countries and remains a substantial public health problem despite recent progress in water and sanitation coverage. Globally, it is estimated that typhoid causes over 16 million cases of illness each year, resulting in over 600,000 deaths. A mathematical model for assessing the impact of educational campaigns on controlling the transmission dynamics of typhoid in the community, has been formulated and analyzed. The reproductive number has been computed. Stability of the model steady-states has been examined. The impact of educational campaigns on controlling the transmission dynamics of typhoid has been discussed through the basic reproductive number and numerical simulations. At its best the study suggests that targeted education campaigns, which are effective at stopping transmission of typhoid more than 40% of the time, will be highly effective at controlling the disease in the community.
Abstract: One of the causes of water pollution is the presence of heavy metals in water. In the present study, an adsorbent prepared from the raw bark of the Pongamia pinnata tree is used for the removal of ferrous or ferric ions from aqueous and waste water containing heavy metals. Adsorption studies were conducted at different pH, concentration of metal ion, amount of adsorbent, contact time, agitation and temperature. The Langmuir and Freundlich adsorption isotherm models were applied for the results. The Langmuir isotherms were best fitted by the equilibrium data. The maximum adsorption was found to 146mg/g in waste water at a temperature of 30°C which is in agreement as comparable to the adsorption capacity of different adsorbents reported in literature. Pseudo second order model best fitted the adsorption of both ferrous and ferric ions.
Abstract: Estimation of the magnitude and causes of poisoning
was the objective of the current study. A retrospective study of
medical records of all poisoning children admitted to Benghazi
Children Hospital in Libya from January 2008 up to December 2010.
Number of children admitted was 244; the age ranged from less than
one to 13 years old. Most of cases were admitted with mild symptom
and the majority of them were boys. Only few cases admitted to
intensive care unit and there was no mortality recorded through the
period of study. Age group 1 to 3 years (50.8%) had the highest
frequency of admission and the peak of admission was during
summer. The most common cause of admission was due to ingestion
of medication (53.69%), House hold product exposure (26.64%) was
the second causes of admission while, 19.67% of admissions were
due to Food poisoning. Almost all admitted cases were accidental and
medicines were the most consumed substances in addition, improper
storage of toxic agents were the first risk factor of poisoning. Present
results indicated that, children poisoning seems to be a common
pediatric care problem which need to control and prevent.
Abstract: The curvature space-time by the presence of material, this deformation must present a pattern of deformation, not random. Space is uniform, elastic and any modification that occurs in one part, causes a change in another.
This deformation exists, must be a constant value and is independent of the observer, and relates the amount of matter, the force caused by the curvature of space and surface space. This unit of space is defined in this study as PIL and represents a constant area of space, deformable in the direction and sense of the center of mass of the body. The PIL is curved and connected to the center of mass of the Earth, to get to that point, through all matter, thus forming part of any place between particles at atomic and subatomic levels. At these levels the space between each particle is flat, unlike the macro where the space curves.
Abstract: At highly congested reinforcement regions, which is common at beam-column joint area, clear spacing between parallel bars becomes less than maximum normal aggregate size (20mm) which has not been addressed in any design code and specifications. Limited clear spacing between parallel bars (herein after thin cover) is one of the causes which affect anchorage performance. In this study, an experimental investigation was carried out to understand anchorage performance of reinforcement in Self-Compacting Concrete (SCC) and Normal Concrete (NC) at highly congested regions under uni-axial tensile loading. Column bar was pullout whereas; beam bars were offset from column reinforcement creating thin cover as per site condition. Two different sizes of coarse aggregate were used for NC (20mm and 10mm). Strain gauges were also installed along the bar in some specimens to understand the internal stress mechanism. Test results reveal that anchorage performance is affected at highly congested reinforcement region in NC with maximum aggregate size 20mm whereas; SCC and Small Aggregate (10mm) gives better structural performance.
Abstract: Learning the gradient of neuron's activity function
like the weight of links causes a new specification which is
flexibility. In flexible neural networks because of supervising and
controlling the operation of neurons, all the burden of the learning is
not dedicated to the weight of links, therefore in each period of
learning of each neuron, in fact the gradient of their activity function,
cooperate in order to achieve the goal of learning thus the number of
learning will be decreased considerably.
Furthermore, learning neurons parameters immunes them against
changing in their inputs and factors which cause such changing.
Likewise initial selecting of weights, type of activity function,
selecting the initial gradient of activity function and selecting a fixed
amount which is multiplied by gradient of error to calculate the
weight changes and gradient of activity function, has a direct affect
in convergence of network for learning.
Abstract: Absorption spectra of infra-red (IR) radiation of the
disperse water medium absorbing the most important greenhouse
gases: CO2 , N2O , CH4 , C2H2 , C2H6 have been calculated by
the molecular dynamics method. Loss of the absorbing ability at the
formation of clusters due to a reduction of the number of centers
interacting with IR radiation, results in an anti-greenhouse effect.
Absorption of O3 molecules by the (H2O)50 cluster is investigated
at its interaction with Cl- ions. The splitting of ozone molecule on
atoms near to cluster surface was observed. Interaction of water
cluster with Cl- ions causes the increase of integrated intensity of
emission spectra of IR radiation, and also essential reduction of the
similar characteristic of Raman spectrum. Relative integrated
intensity of absorption of IR radiation for small water clusters was
designed. Dependences of the quantity of weight on altitude for
vapor of monomers, clusters, droplets, crystals and mass of all
moisture were determined. The anti-greenhouse effect of clusters was
defined as the difference of increases of average global temperature
of the Earth, caused by absorption of IR radiation by free water
molecules forming clusters, and absorption of clusters themselves.
The greenhouse effect caused by clusters makes 0.53 K, and the antigreenhouse
one is equal to 1.14 K. The increase of concentration of
CO2 in the atmosphere does not always correlate with the
amplification of greenhouse effect.
Abstract: Pore water pressure is normally because of
consolidation, compaction and water level fluctuation on reservoir.
Measuring, controlling and analyzing of pore water pressure have
significant importance in both of construction and operation period.
Since end of 2002, (dam start up) nature of KARKHEH dam has
been analyzed by using the gathered information from
instrumentation system of dam. In this lecture dam condition after
start up have been analyzed by using the gathered data from located
piezometers in core of dam. According to TERZAGHI equation and
records of piezometers, consolidation lasted around five years during
early years of construction stage, and current pore water pressure in
core of dam is caused by water level fluctuation in reservoir.
Although there is time lag between water level fluctuation and results
of piezometers. These time lags have been checked and the results
clearly show that one of the most important causes of it is distance
between piezometer and reservoir.
Abstract: Heterogeneous repolarization causes dispersion of the T-wave and has been linked to arrhythmogenesis. Such heterogeneities appear due to differential expression of ionic currents in different regions of the heart, both in healthy and diseased animals and humans. Mice are important animals for the study of heart diseases because of the ability to create transgenic animals. We used our previously reported model of mouse ventricular myocytes to develop 2D mouse ventricular tissue model consisting of 14,000 cells (apical or septal ventricular myocytes) and to study the stability of action potential propagation and Ca2+ dynamics. The 2D tissue model was implemented as a FORTRAN program code for highperformance multiprocessor computers that runs on 36 processors. Our tissue model is able to simulate heterogeneities not only in action potential repolarization, but also heterogeneities in intracellular Ca2+ transients. The multicellular model reproduced experimentally observed velocities of action potential propagation and demonstrated the importance of incorporation of realistic Ca2+ dynamics for action potential propagation. The simulations show that relatively sharp gradients of repolarization are predicted to exist in 2D mouse tissue models, and they are primarily determined by the cellular properties of ventricular myocytes. Abrupt local gradients of channel expression can cause alternans at longer pacing basic cycle lengths than gradual changes, and development of alternans depends on the site of stimulation.
Abstract: Fluency is a skill that, unfortunately, many students
lack. This deficiency causes students to be frustrated with, and
overwhelmed by, the act of reading. However, research suggests that
the repeated reading method may help students to improve their
fluency. This study examines the effects of repeated readings on
student fluency. The study-s overarching question is: What effect do
increases in repeated reading have on reading fluency among middle
school students from diverse backgrounds? More specifically, the
authors examine whether repeated reading improves the fluency,
reading speed, reading-oriented self-esteem, and confidence of
students of diverse academic abilities, socio-economics statuses, and
racial and ethnic backgrounds. To examine these questions the
authors conducted a study using repeated reading strategies with a
sample of students from an urban, middle school in the southeastern
United States. We found that, on average, the use of repeated reading
strategies increased students- fluency, words per minute (wpm)
reading score, reading-oriented self-esteem, and confidence.
Abstract: Natural fibres have emerged as the potential reinforcement material for composites and thus gain attraction by many researchers. This is mainly due to their applicable benefits as they offer low density, low cost, renewable, biodegradability and environmentally harmless and also comparable mechanical properties with synthetic fibre composites. The properties of hybrid composites highly depends on several factors, including the interaction of fillers with the polymeric matrix, shape and size (aspect ratio), and orientation of fillers [1]. In this study, natural fibre kenaf composites and kenaf/fibreglass hybrid composites were fabricated by a combination of hand lay-up method and cold-press method. The effect of different fibre types (powder, short and long) on the tensile properties of composites is investigated. The kenaf composites with and without the addition of fibreglass were then characterized by tensile testing and scanning electron microscopy. A significant improvement in tensile strength and modulus were indicated by the introduction of long kenaf/woven fibreglass hybrid composite. However, the opposite trends are observed in kenaf powder composite. Fractographic observation shows that fibre/matrix debonding causes the fibres pull out. This phenomenon results in the fibre and matrix fracture.
Abstract: Although women have merit in their jobs, they still
are located very few in the top management in many sectors. There
are many causes of such situation. Such a situation creates obstacles;
especially invisible ones are called “glass ceiling syndrome”. Also,
studies which handle this subject in academic community are very
few. The aim of this research is to reach the results about glass
ceiling obstacles in terms of female teaching staff (academics)
working in higher education institutions. To this end, our study was
performed on female academics working at Selcuk University, Konya
/ Turkey. Our study's main aim can be expressed as to determine
whether there are glass ceiling obstacles for female academics
working at the higher education institution in question, to measure
their glass ceiling perceptions and, thus, to identify what the glass
ceiling barrier components for them to promotion to senior
management positions are.
Abstract: The performance of ground to deep space optical
communication systems is degraded by distortion of the beam as it
propagates through the turbulent atmosphere. Turbulence causes
fluctuations in the intensity of the received signal which ultimately
affects the acquisition time required to acquire and locate the spaceborne
target using narrow laser beam. In this paper, performance of
free-space optical (FSO) communication system in atmospheric
turbulence has been analyzed in terms of acquisition time for
coherent and non-coherent modulation schemes. Numerical results
presented in graphical and tabular forms show that the acquisition
time increases with the increase in turbulence level. This is true for
both schemes. The BPSK has lowest acquisition time among all
schemes. In non-coherent schemes, M-PPM performs better than the
other schemes. With the increase in M, acquisition time becomes
lower, but at the cost of increase in system complexity.
Abstract: The use of plastic materials in agriculture causes
serious hazards to the environment. The introduction of biodegradable materials, which can be disposed directly into the soil
can be one possible solution to this problem. In the present research results of experimental tests carried out on biodegradable film
fabricated from natural waste (corn husk) are presented. The film was
characterized by Fourier transform infrared spectroscopy (FTIR),
differential scanning calorimeter (DSC), thermal gravimetric analysis
(TGA) and atomic force microscope (AFM) observation. The film is
shown to be readily degraded within 7-9 months under controlled soil
conditions, indicating a high biodegradability rate. The film
fabricated was use to produce biodegradable pot (BioPot) for
seedlings plantation. The introduction and the expanding use of
biodegradable materials represent a really promising alternative for
enhancing sustainable and environmentally friendly agricultural
activities.
Abstract: Job stress is one of the most important concepts for
the today-s corporate as well as institutional world. The current study
is conducted to identify the causes of faculty stress at Higher
Education in Pakistan. For the purpose, Public & Private Business
Schools of Punjab is selected as representative of Pakistan. A sample
of 300 faculty members (214 males, 86 females) responded to the
survey. Regression analysis shows that the Workload, Student
Related issues and Role Conflicts are the major sources contributing
significantly towards producing stress. The study also revealed that
Private sector faculty members experienced more stress as compared
to faculty in Public sector Business Schools. Moreover, females,
younger ages, lower designation & low qualification faculty
members experience more stress as compared to males, older ages,
higher designation and high qualification. The study yield many
significant results for the policy makers of Business Institutions.