Abstract: The purpose of this study was to elucidate the factors affecting antimicrobial effectiveness of essential oils against food spoilage and pathogenic bacteria. The minimum inhibition concentrations (MIC) of the essential oils, were determined by turbidimetric technique using Biocreen C, analyzer. The effects of pH ranging from 7.3 to 5.5 in absence and presence of essential oils and/or NaCl on the lag time and mean generation time of the bacteria at 370C, were carried out and results were determined showed that, combination of low pH and essential oil at 370C had additive effects against the test micro-organisms. The combination of 1.2 % (w/v) of NaCl and clove essential oil at 0.0325% (v/v) was effective against E. coli. The use of concentrations less than MIC in combination with low pH and or NaCl has the potential of being used as an alternative to “traditional food preservatives".
Abstract: This paper proposes a delay-dependent leader-following consensus condition of multi-agent systems with both communication delay and probabilistic self-delay. The proposed methods employ a suitable piecewise Lyapunov-Krasovskii functional and the average dwell time approach. New consensus criterion for the systems are established in terms of linear matrix inequalities (LMIs) which can be easily solved by various effective optimization algorithms. Numerical example showed that the proposed method is effective.
Abstract: Safety Health and Environment Code of Practice (SHE
COP) was developed to help road transportation operators to manage
its operation in a systematic and safe manner. A study was conducted
to determine the effectiveness of SHE COP implementation during
non-OPS period. The objective of the study is to evaluate the
implementations of SHE COP among bus operators during wee hour
operations. The data was collected by completing a set of checklist
after observing the activities during pre departure, during the trip, and
upon arrival. The results show that there are seven widely practiced
SHE COP elements. 22% of the buses have average speed exceeding
the maximum permissible speed on the highways (90 km/h), with
13% of the buses were travelling at the speed of more than 100 km/h.
The statistical analysis shows that there is only one significant
association which relates speeding with prior presence of
enforcement officers.
Abstract: Technology transfer of renewable energy technologies is very often unsuccessful in the developing world. Aside from challenges that have social, economic, financial, institutional and environmental dimensions, technology transfer has generally been misunderstood, and largely seen as mere delivery of high tech equipment from developed to developing countries or within the developing world from R&D institutions to society. Technology transfer entails much more, including, but not limited to: entire systems and their component parts, know-how, goods and services, equipment, and organisational and managerial procedures. Means to facilitate the successful transfer of energy technologies, including the sharing of lessons are subsequently extremely important for developing countries as they grapple with increasing energy needs to sustain adequate economic growth and development. Improving the success of technology transfer is an ongoing process as more projects are implemented, new problems are encountered and new lessons are learnt. Renewable energy is also critical to improve the quality of lives of the majority of people in developing countries. In rural areas energy is primarily traditional biomass. The consumption activities typically occur in an inefficient manner, thus working against the notion of sustainable development. This paper explores the implementation of technology transfer in the developing world (sub-Saharan Africa). The focus is necessarily on RETs since most rural energy initiatives are RETs-based. Additionally, it aims to highlight some lessons drawn from the cited RE projects and identifies notable differences where energy technology transfer was judged to be successful. This is done through a literature review based on a selection of documented case studies which are judged against the definition provided for technology transfer. This paper also puts forth research recommendations that might contribute to improved technology transfer in the developing world. Key findings of this paper include: Technology transfer cannot be complete without satisfying pre-conditions such as: affordability, maintenance (and associated plans), knowledge and skills transfer, appropriate know how, ownership and commitment, ability to adapt technology, sound business principles such as financial viability and sustainability, project management, relevance and many others. It is also shown that lessons are learnt in both successful and unsuccessful projects.
Abstract: The present study was provided to examine the
vortical structures generated by two inclined impinging jets with
experimental and numerical investigations. The jets are issuing with a
pitch angle α=40° into a confined quiescent fluid. The experimental
investigation on flow patterns was visualized by using olive particles
injected into the jets illuminated by Nd:Yag laser light to reveal the
finer details of the confined jets interaction. It was observed that two
counter-rotating vortex pairs (CVPs) were generated in the near
region. A numerical investigation was also performed. First, the
numerical results were validates against the experimental results and
then the numerical model was used to study the effect of section ratio
on the evolution of the CVPs. Our results show promising agreement
with experimental data, and indicate that our model has the potential
to produce useful and accurate data regarding the evolution of CVPs.
Abstract: Stock portfolio selection is a classic problem in finance,
and it involves deciding how to allocate an institution-s or an individual-s
wealth to a number of stocks, with certain investment objectives
(return and risk). In this paper, we adopt the classical Markowitz
mean-variance model and consider an additional common realistic
constraint, namely, the cardinality constraint. Thus, stock portfolio
optimization becomes a mixed-integer quadratic programming problem
and it is difficult to be solved by exact optimization algorithms.
Chemical Reaction Optimization (CRO), which mimics the molecular
interactions in a chemical reaction process, is a population-based
metaheuristic method. Two different types of CRO, named canonical
CRO and Super Molecule-based CRO (S-CRO), are proposed to solve
the stock portfolio selection problem. We test both canonical CRO
and S-CRO on a benchmark and compare their performance under
two criteria: Markowitz efficient frontier (Pareto frontier) and Sharpe
ratio. Computational experiments suggest that S-CRO is promising
in handling the stock portfolio optimization problem.
Abstract: In this paper we present the deep study about the Bio-
Medical Images and tag it with some basic extracting features (e.g.
color, pixel value etc). The classification is done by using a nearest
neighbor classifier with various distance measures as well as the
automatic combination of classifier results. This process selects a
subset of relevant features from a group of features of the image. It
also helps to acquire better understanding about the image by
describing which the important features are. The accuracy can be
improved by increasing the number of features selected. Various
types of classifications were evolved for the medical images like
Support Vector Machine (SVM) which is used for classifying the
Bacterial types. Ant Colony Optimization method is used for optimal
results. It has high approximation capability and much faster
convergence, Texture feature extraction method based on Gabor
wavelets etc..
Abstract: We considered repeated-root cyclic codes whose
block length is divisible by the characteristic of the underlying field.
Cyclic self dual codes are also the repeated root cyclic codes. It is
known about the one-level squaring construction for binary repeated
root cyclic codes. In this correspondence, we introduced of two
level squaring construction for binary repeated root cyclic codes of
length 2a b , a > 0, b is odd.
Abstract: This paper presents and discusses the numerical simulations of transient laminar natural convection cooling of high Prandtl number fluids in cubical cavities, in which the six walls of the cavity are subjected to a step change in temperature. The effect of the fluid Prandtl number on the heat transfer coefficient is studied for three different fluids (Golden Syrup, Glycerin and Glycerin-water solution 50%). The simulations are performed at two different Rayleigh numbers (5·106 and 5·107) and six different Prandtl numbers (3 · 105 ≥Pr≥ 50). Heat conduction through the cavity glass walls is also considered. The propsed correlations of the averaged heat transfer coefficient (N u) showed that it is dependant on the initial Ra and almost independent on P r. The instantaneous flow patterns, temperature contours and time evolution of volume averaged temperature and heat transfer coefficient are presented and analyzed.
Abstract: This study assessed fish marketing as panacea towards
sustainable agriculture in Ogun State, Nigeria. Multi-stage sampling
technique was used in the selection of 150 fish marketers for this
study. Descriptive statistics were used for the objectives while
Product Pearson Moment Correlation was used to test the hypothesis.
Result of the findings revealed that the mean age of the respondents
was 38.60 years. Majority (93.33%) of the respondents had
acceptable levels of formal education. Many (44.00%) of the
respondents had spent 1-5 years in fish marketing. The average
quantity of fish sold in a day was 94.10kg. However, efficient fish
marketing were hindered by inadequate processing equipment,
storage rooms and ice holding facilities (86.67%). There was a
significant relationship between socio-economic characteristics and
profit realized from fish marketing (p < 0.05). It was recommended
that storage and warehousing facilities should be provided to the fish
marketers in the study area.
Abstract: There is a paucity of data on the prevalence of alcohol
use and related problems among foreign students in Belarus. We
therefore screen for the prevalence of alcohol related problems
among the general foreign students- population in Minsk, Belarus.
Participants were 135 male university foreign students (average age –
21) from three major universities in Minsk, Belarus. All respondents
were administered questionnaire, containing the AUDIT, CAGE,
MAST and other alcohol related questions. Overall, 62.2% (n=84)
alcohol users and 31.1% (n=42) problem drinkers were identified on
the AUDIT. There was a significant increase (from 39.3% to 60.7%)
of the total alcohol users after arrival in Belarus (¤ç2 = 7.714, p
Abstract: A cross sectional study design and standard
microbiological procedures were used to determine the prevalence
and antimicrobial susceptibility patterns of Escherichia coli,
Salmonella enterica serovar typhimurium and Vibrio cholerae O1
isolated from water and two fish species Rastrineobola argentea and
Oreochromis niloticus collected from fish landing beaches and
markets in the Lake Victoria Basin of western Kenya. Out of 162
samples analyzed, 133 (82.1%) were contaminated, with S.
typhimurium as the most prevalent (49.6%), followed by E. coli
(46.6%), and lastly V. cholerae (2.8%). All the bacteria isolates were
sensitive to ciprofloxacin. E. coli isolates were resistant to ampicillin,
tetracycline, cotrimoxazole, chloramphenical and gentamicin while
S. typhimurium isolates exhibited resistance to ampicillin,
tetracycline, and cotrimoxazole. The V. cholerae O1 isolates were
resistant to tetracycline and ampicillin. The high prevalence of drug
resistant enteric bacteria in water and fish from the study region
needs public health intervention from the local government.
Abstract: This work presents a recursive identification algorithm. This algorithm relates to the identification of closed loop system with Variable Structure Controller. The approach suggested includes two stages. In the first stage a genetic algorithm is used to obtain the parameters of switching function which gives a control signal rich in commutations (i.e. a control signal whose spectral characteristics are closest possible to those of a white noise signal). The second stage consists in the identification of the system parameters by the instrumental variable method and using the optimal switching function parameters obtained with the genetic algorithm. In order to test the validity of this algorithm a simulation example is presented.
Abstract: WiMAX and Wi-Fi are considered as the promising
broadband access solutions for wireless MAN’s and LANs,
respectively. In the recent works WiMAX is considered suitable as a
backhaul service to connect multiple dispersed Wi-Fi ‘hotspots’.
Hence a new integrated WiMAX/Wi-Fi architecture has been
proposed in literatures. In this paper the performance of an integrated
WiMAX/Wi-Fi network has been investigated by streaming a video
conference application. The difference in performance between the
two protocols is compared with respect to video conferencing. The
Heterogeneous network was simulated in the OPNET simulator.
Abstract: Visfatin and apelin are two new adipokines that recently gained a special interest in diabetes research. This study was conducted to study the interplay between these two adipokines and their correlation with other inflammatory and biochemical parameters in type 2 diabetic (T2D) postmenopausal women with CAD. Visfatin and apelin were measured by enzyme-linked immunoassay (ELISA). Visfatin was found to be significantly higher in the following groups: T2D patients without CAD, non-obese and obese T2D patients with CAD when compared to control group. Apelin was found to be significantly lower in non-obese and obese T2D patients with CAD when compared to control group. Visfatin and apelin were found to be significantly associated with each other and with other biochemical parameters. The current study provides evidence for the interplay between visfatin and apelin through the inflammatory milieu characteristic of T2D and their possible role in the pathogenesis of CAD complication of T2D.
Abstract: Number of documents being created increases at an
increasing pace while most of them being in already known topics
and little of them introducing new concepts. This fact has started a
new era in information retrieval discipline where the requirements
have their own specialties. That is digging into topics and concepts
and finding out subtopics or relations between topics. Up to now IR
researches were interested in retrieving documents about a general
topic or clustering documents under generic subjects. However these
conventional approaches can-t go deep into content of documents
which makes it difficult for people to reach to right documents they
were searching. So we need new ways of mining document sets
where the critic point is to know much about the contents of the
documents. As a solution we are proposing to enhance LSI, one of
the proven IR techniques by supporting its vector space with n-gram
forms of words. Positive results we have obtained are shown in two
different application area of IR domain; querying a document
database, clustering documents in the document database.
Abstract: A considerable amount of energy is consumed during
transmission and reception of messages in a wireless mesh network
(WMN). Reducing per-node transmission power would greatly
increase the network lifetime via power conservation in addition to
increasing the network capacity via better spatial bandwidth reuse. In
this work, the problem of topology control in a hybrid WMN of
heterogeneous wireless devices with varying maximum transmission
ranges is considered. A localized distributed topology control
algorithm is presented which calculates the optimal transmission
power so that (1) network connectivity is maintained (2) node
transmission power is reduced to cover only the nearest neighbours
(3) networks lifetime is extended. Simulations and analysis of results
are carried out in the NS-2 environment to demonstrate the
correctness and effectiveness of the proposed algorithm.
Abstract: The wavelet transform is one of the most important
method used in signal processing. In this study, we have introduced
frequency-energy characteristics of local earthquakes using discrete
wavelet transform. Frequency-energy characteristic was analyzed
depend on difference between P and S wave arrival time and noise
within records. We have found that local earthquakes have similar
characteristics. If frequency-energy characteristics can be found
accurately, this gives us a hint to calculate P and S wave arrival time.
It can be seen that wavelet transform provides successful
approximation for this. In this study, 100 earthquakes with 500
records were analyzed approximately.
Abstract: According to celebrated Hurwitz theorem, there exists
four division algebras consisting of R (real numbers), C (complex
numbers), H (quaternions) and O (octonions). Keeping in view
the utility of octonion variable we have tried to extend the three
dimensional vector analysis to seven dimensional one. Starting with
the scalar and vector product in seven dimensions, we have redefined
the gradient, divergence and curl in seven dimension. It is shown
that the identity n(n - 1)(n - 3)(n - 7) = 0 is satisfied only
for 0, 1, 3 and 7 dimensional vectors. We have tried to write all
the vector inequalities and formulas in terms of seven dimensions
and it is shown that same formulas loose their meaning in seven
dimensions due to non-associativity of octonions. The vector formulas
are retained only if we put certain restrictions on octonions and split
octonions.
Abstract: The purpose of the present study was to evaluate the
epidemiology of waterborne diarrhoeal among children aged 6-36
months old in Busia town, western Kenya. The study was carried out
between Feb. 2008 and Feb. 2010. Cases of diarrhoea reported in 385
households were linked to household water handling practices. A
mother with a child of 6-36 months old was also included in the
study. Diarrhoea prevalence among children 6-36 months was 16.7%
in Busia town, Bwamani (19.6%) and Mayenje (10.6%) clustered in
Mayenje sub-location reported the highest and the lowest prevalence
of diarrhoea. There was a positive correlation between the prevalence
of diarrhoea in children and the level of the mother-s education,
29.9% (n= 100). Diarrhoea cases decreased in range from 35.5% (n
=102) to 4.8% (n= 16), corresponding to increase in age from 6-35
months on average. In conclusion, prevalence of diarrhoea in
children of 6-36 months old was 16.7% in Busia town. This was
higher in children whose mother-s age was below 18 years and with
low level of education, the rate decreased with increase in age of
children. Prevalence of diarrhoea in children aged 6-36months in
households was higher in children aged 6-17 and 36 months and
whose mothers were less educated and fell between the ages of 18-24
years. The Influence of human activities at the main source of
drinking water on the prevalence of diarrhoea in these children was
insignificant.