Abstract: This paper presents the theoretical investigation of a
slotted patch antenna. The main objective of proposed work is to
obtain a large bandwidth antenna with reduced size. The antenna has
a compact size of 21.1mm x 20.25mm x 8.5mm. Two designs with
minor variation are studied which provide wide impedance
bandwidths of 24.056% and 25.63% respectively with the use of
parasitic elements when excited by a probe feed. The advantages of
this configuration are its compact size and the wide range of
frequencies covered. A parametric study is also conducted to
investigate the characteristics of the antenna under different
conditions. The measured return loss and radiation pattern indicate
the suitability of this design for WLAN applications, namely, Wi-
Max, 802.11a/b/g and ISM bands.
Abstract: The present study was designed to demonstrate the seasonal variations in physico-chemical parameters of fish farm at Govt. Nursery Unit, Muzaffargarh, Department of Fisheries Govt. of Punjab, Pakistan for a period of eight months from January to August 2008. Water samples were collected on fifteen days basis and have been analyzed for estimation of Air temperature, Water temperature, Light penetration, pH, Total dissolved oxygen, Clouds, Carbonates, Bicarbonates, Total carbonates, Total dissolved solids, Chlorides, Calcium and Hardness. Seasonal fluctuations were observed in all the physico-chemical parameters of fish farm. The overall physicochemical parameters of fish pond water remained within the tolerable range throughout the study period.
Abstract: Because of the global warming and the rising sea level, residents living in southwestern coastland, Taiwan are faced with the submerged land and may move to higher elevation area. It is desirable to discuss the key consideration factor for selecting the migration location under five dimensions of ಯ security”, “health”, “convenience”, “comfort” and “socio-economic” based on the document reviews. This paper uses the Structural Equation Modeling (SEM) and the questionnaire survey. The analysis results show that the convenience is the most key factor for residents in Taiwan.
Abstract: This study experimentally and numerically investigates
motor cooling performance. The motor consists of a centrifugal fan,
two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637
cooling tubes. The pressure rise-flow rate (P-Q) performance curves of
the cooling fans at 1800 rpm are tested using a test apparatus
complying with the Chinese National Standard (CNS) 2726.
Compared with the experimental measurements, the numerical
analysis results show that the P-Q performance curves of the axial fan
and centrifugal fan can be estimated within about 2% and 6%,
respectively. By using the simplified model, setting up the heat
exchanger and stator as porous media, the flow field in the motor is
calculated. By using the results of the flow field near the rotor and
stator, and subjecting the heat generation rate as a boundary condition,
the temperature distributions of the stator and rotor are also calculated.
The simulation results show that the calculated temperature of the
stator winding near the axial fans is lower by about 5% than the
measured value, and the calculated temperature of the stator core
located at the center of the stator is about 1% higher than the measured
value. Besides, discussion is made to improve the motor cooling
performance.
Abstract: Using 1km grid datasets representing monthly mean
precipitation, monthly mean temperature, and dry matter production
(DMP), we considered the regional plant production ability in
Southeast and South Asia, and also employed pixel-by-pixel
correlation analysis to assess the intensity of relation between climate
factors and plant production. While annual DMP in South Asia was
approximately less than 2,000kg, the one in most part of Southeast
Asia exceeded 2,500 - 3,000kg. It suggested that plant production in
Southeast Asia was superior to South Asia, however, Rain-Use
Efficiency (RUE) representing dry matter production per 1mm
precipitation showed that inland of Indochina Peninsula and India
were higher than islands in Southeast Asia. By the results of
correlation analysis between climate factors and DMP, while the area
in most parts of Indochina Peninsula indicated negative correlation
coefficients between DMP and precipitation or temperature, the area
in Malay Peninsula and islands showed negative correlation to
precipitation and positive one to temperature, and most part of India
dominating South Asia showed positive to precipitation and negative
to temperature. In addition, the areas where the correlation coefficients
exceeded |0.8| were regarded as “susceptible" to climate factors, and
the areas smaller than |0.2| were “insusceptible". By following the
discrimination, the map implying expected impacts by climate change
was provided.
Abstract: Voice over Internet Protocol (VoIP) application or commonly known as softphone has been developing an increasingly large market in today-s telecommunication world and the trend is expected to continue with the enhancement of additional features. This includes leveraging on the existing presence services, location and contextual information to enable more ubiquitous and seamless communications. In this paper, we discuss the concept of seamless session transfer for real-time application such as VoIP and IPTV, and our prototype implementation of such concept on a selected open source VoIP application. The first part of this paper is about conducting performance evaluation and assessments across some commonly found open source VoIP applications that are Ekiga, Kphone, Linphone and Twinkle so as to identify one of them for implementing our design of seamless session transfer. Subjective testing has been carried out to evaluate the audio performance on these VoIP applications and rank them according to their Mean Opinion Score (MOS) results. The second part of this paper is to discuss on the performance evaluations of our prototype implementation of session transfer using Linphone.
Abstract: In this study the mixed mode fracture mechanics
parameters were investigated for high tensile steel butt welded joint
based on modified Arcan test and finite element analysis was used to
evaluate the effect of crack length on fracture criterion. The nondimensional
stress intensity factors, strain energy release rates and Jintegral
energy on crack tip were obtained for various in-plane
loading combinations on Arcan specimen starting from pure mode-I
to pure mode-II loading conditions. The specimen and apparatus were
modeled by finite element method and analyzed under various
loading angles (between 0 to 90 degrees with 15 degree interval) to
simulate the pure mode-I, II and mixed mode fracture. Since the
analytical results are independent from elasticity modules for
isotropic materials, therefore the results in elastic fields can be used
for Arcan specimens. The main objective of this study was to
evaluate the geometric calibration factors for modified Arcan test
specimen in order to obtain fracture toughness under mixed mode
loading conditions.
Abstract: Construction of portable device for fast analysis of energetic materials is described in this paper. The developed analytical system consists of two main parts: a miniaturized microcolumn liquid chromatograph of unique construction and original chemiluminescence detector. This novel portable device is able to determine selectively most of nitramine- and nitroester-based explosives as well as inorganic nitrates at trace concentrations in water or soil extracts in less than 8 minutes.
Abstract: The paper deals with the most important changes that have occurred in business because of social media and its impact on organisations and leadership in recent years. It seeks to synthesize existing research, theories and concepts, in order to understand "social destinations", and to provide a bridge from past research to future success. Becoming a "social destination" is a strategic and tactical leadership and management issue and the paper will present the importance of destination leadership in choosing the way towards a social destination and some organisational models. It also presents some social media tools that can be used in transforming a destination into a social one. Adapting organisations to the twentyfirst century means adopting social media as a way of life and a way of business.
Abstract: We report on the results of a pilot study in which a data-mining tool was developed for mining audiology records. The records were heterogeneous in that they contained numeric, category and textual data. The tools developed are designed to observe associations between any field in the records and any other field. The techniques employed were the statistical chi-squared test, and the use of self-organizing maps, an unsupervised neural learning approach.
Abstract: Hazardous Material transportation by road is coupled
with inherent risk of accidents causing loss of lives, grievous injuries,
property losses and environmental damages. The most common type
of hazmat road accident happens to be the releases (78%) of
hazardous substances, followed by fires (28%), explosions (14%) and
vapour/ gas clouds (6 %.).
The paper is discussing initially the probable 'Impact Zones'
likely to be caused by one flammable (LPG) and one toxic (ethylene
oxide) chemicals being transported through a sizable segment of a
State Highway connecting three notified Industrial zones in Surat
district in Western India housing 26 MAH industrial units. Three
'hotspots' were identified along the highway segment depending on
the particular chemical traffic and the population distribution within
500 meters on either sides. The thermal radiation and explosion
overpressure have been calculated for LPG / Ethylene Oxide BLEVE
scenarios along with toxic release scenario for ethylene oxide.
Besides, the dispersion calculations for ethylene oxide toxic release
have been made for each 'hotspot' location and the impact zones
have been mapped for the LOC concentrations. Subsequently, the
maximum Initial Isolation and the protective zones were calculated
based on ERPG-3 and ERPG-2 values of ethylene oxide respectively
which are estimated taking the worst case scenario under worst
weather conditions. The data analysis will be helpful to the local
administration in capacity building with respect to rescue /
evacuation and medical preparedness and quantitative inputs to
augment the District Offsite Emergency Plan document.
Abstract: Almost all Libyan industries (both private and public) have struggled with many difficulties during the past three decades due to many problems. These problems have created a strongly negative impact on the productivity and utilization of many companies within Libya. This paper studies the current awareness and implementation levels of Just-In-Time (JIT) within the Libyan Textile private industry. A survey has been applied in this study using an intensive detailed questionnaire. Based on the analysis of the survey responses, the results show that the management body within the surveyed companies has a modest strategy towards most of the areas that are considered as being very crucial in any successful implementation of JIT. The results also show a variation within the implementation levels of the JIT elements as these varies between Low and Acceptable levels. The paper has also identified limitations within the investigated areas within this industry, and has pointed to areas where senior managers within the Libyan textile industry should take immediate actions in order to achieve effective implementation of JIT within their companies.
Abstract: Amount of dissolve oxygen in a river has a great direct affect on aquatic macroinvertebrates and this would influence on the region ecosystem indirectly. In this paper it is tried to predict dissolved oxygen in rivers by employing an easy Fuzzy Logic Modeling, Wang Mendel method. This model just uses previous records to estimate upcoming values. For this purpose daily and hourly records of eight stations in Au Sable watershed in Michigan, United States are employed for 12 years and 50 days period respectively. Calculations indicate that for long period prediction it is better to increase input intervals. But for filling missed data it is advisable to decrease the interval. Increasing partitioning of input and output features influence a little on accuracy but make the model too time consuming. Increment in number of input data also act like number of partitioning. Large amount of train data does not modify accuracy essentially, so, an optimum training length should be selected.
Abstract: Food borne illnesses have been reported to be a global
health challenge. Annual incidences of food–related diseases involve
76 million cases, of which only 14 million can be traced to known
pathogens. Poor hygienic practices have contributed greatly to this. It
has been reported that in the year 2000 about 2.1 million people died
from diarrheal diseases, hence, there is a need to ensure food safety at
all level. This study focused on the sterility examination and
inhibitory effect of honey samples on selected gram negative and
gram positive food borne pathogen from South West Nigeria. The
laboratory examinations revealed the presence of some bacterial and
fungal contaminations of honey samples and that inhibitory activity
of the honey sample was more pronounced on the gram negative
bacteria than the gram positive bacterial isolates. Antibiotic
sensitivity test conducted on the different bacterial isolates also
showed that honey was able to inhibit the proliferation of the tested
bacteria than the employed antibiotics.
Abstract: We proposed a technique to identify road traffic
congestion levels from velocity of mobile sensors with high accuracy
and consistent with motorists- judgments. The data collection utilized
a GPS device, a webcam, and an opinion survey. Human perceptions
were used to rate the traffic congestion levels into three levels: light,
heavy, and jam. Then the ratings and velocity were fed into a
decision tree learning model (J48). We successfully extracted vehicle
movement patterns to feed into the learning model using a sliding
windows technique. The parameters capturing the vehicle moving
patterns and the windows size were heuristically optimized. The
model achieved accuracy as high as 99.68%. By implementing the
model on the existing traffic report systems, the reports will cover
comprehensive areas. The proposed method can be applied to any
parts of the world.
Abstract: The use of amine mixtures employing
methyldiethanolamine (MDEA), monoethanolamine (MEA), and diethanolamine (DEA) have been investigated for a variety of cases
using a process simulation program called HYSYS. The results show that, at high pressures, amine mixtures have little or no advantage in the cases studied. As the pressure is lowered, it becomes more difficult for MDEA to meet residual gas requirements and mixtures can usually improve plant performance. Since the CO2 reaction rate
with the primary and secondary amines is much faster than with
MDEA, the addition of small amounts of primary or secondary amines to an MDEA based solution should greatly improve the overall reaction rate of CO2 with the amine solution. The addition of MEA caused the CO2 to be absorbed more strongly in the upper portion of the column than for MDEA along. On the other hand,
raising the concentration for MEA to 11%wt, CO2 is almost
completely absorbed in the lower portion of the column. The addition of MEA would be most advantageous.
Thus, in areas where MDEA cannot meet the residual gas
requirements, the use of amine mixtures can usually improve the plant
performance.
Abstract: The third generation (3G) of cellular system adopted
the spread spectrum as solution for the transmission of the data in the
physical layer. Contrary to systems IS-95 or CDMAOne (systems
with spread spectrum of the preceding generation), the new standard,
called Universal Mobil Telecommunications System (UMTS), uses
long codes in the down link. The system is conceived for the vocal
communication and the transmission of the data. In particular, the
down link is very important, because of the asymmetrical request of
the data, i.e., more remote loading towards the mobiles than towards
the basic station. Moreover, the UMTS uses for the down link an
orthogonal spreading out with a variable factor of spreading out
(OVSF for Orthogonal Variable Spreading Factor). This
characteristic makes it possible to increase the flow of data of one or
more users by reducing their factor of spreading out without
changing the factor of spreading out of other users. In the current
standard of the UMTS, two techniques to increase the performances
of the down link were proposed, the diversity of sending antenna and
the codes space-time. These two techniques fight only fainding. The
receiver proposed for the mobil station is the RAKE, but one can
imagine a receiver more sophisticated, able to reduce the interference
between users and the impact of the coloured noise and interferences
to narrow band. In this context, where the users have long codes
synchronized with variable factor of spreading out and ignorance by
the mobile of the other active codes/users, the use of the sequences of
code pseudo-noises different lengths is presented in the form of one
of the most appropriate solutions.
Abstract: The structure of retinal vessels is a prominent feature,
that reveals information on the state of disease that are reflected in
the form of measurable abnormalities in thickness and colour.
Vascular structures of retina, for implementation of clinical diabetic
retinopathy decision making system is presented in this paper.
Retinal Vascular structure is with thin blood vessel, whose accuracy
is highly dependent upon the vessel segmentation. In this paper the
blood vessel thickness is automatically detected using preprocessing
techniques and vessel segmentation algorithm. First the capture
image is binarized to get the blood vessel structure clearly, then it is
skeletonised to get the overall structure of all the terminal and
branching nodes of the blood vessels. By identifying the terminal
node and the branching points automatically, the main and branching
blood vessel thickness is estimated. Results are presented and
compared with those provided by clinical classification on 50 vessels
collected from Bejan Singh Eye hospital..
Abstract: Data Envelopment Analysis (DEA) is a methodology
that computes efficiency values for decision making units (DMU) in a
given period by comparing the outputs with the inputs. In many cases,
there are some time lag between the consumption of inputs and the
production of outputs. For a long-term research project, it is hard to
avoid the production lead time phenomenon. This time lag effect
should be considered in evaluating the performance of organizations.
This paper suggests a model to calculate efficiency values for the
performance evaluation problem with time lag. In the experimental
part, the proposed methods are compared with the CCR and an
existing time lag model using the data set of the 21st century frontier
R&D program which is a long-term national R&D program of Korea.
Abstract: This paper examined the influence of matching
students- learning preferences with the teaching methodology
adopted, on their academic performance in an accounting course in
two types of learning environment in one university in Lebanon:
classes with PowerPoint (PPT) vs. conventional classes. Learning
preferences were either for PPT or for Conventional methodology. A
statistically significant increase in academic achievement is found in
the conventionally instructed group as compared to the group taught
with PPT. This low effectiveness of PPT might be attributed to the
learning preferences of Lebanese students. In the PPT group, better
academic performance was found among students with
learning/teaching match as compared with students with
learning/teaching mismatch. Since the majority of students display a
preference for the conventional methodology, the result might
suggest that Lebanese students- performance is not optimized by PPT
in the accounting classrooms, not because of PPT itself, but because
it is not matching the Lebanese students- learning preferences in such
a quantitative course.