Abstract: In this work, we successfully extended one-dimensional differential transform method (DTM), by presenting and proving some theorems, to solving nonlinear high-order multi-pantograph equations. This technique provides a sequence of functions which converges to the exact solution of the problem. Some examples are given to demonstrate the validity and applicability of the present method and a comparison is made with existing results.
Abstract: The aim of this paper is to present the kinematic
analysis and mechanism design of an assistive robotic leg for
hemiplegic and hemiparetic patients. In this work, the priority is to
design and develop the lightweight, effective and single driver
mechanism on the basis of experimental hip and knee angles- data for
walking speed of 1 km/h. A mechanism of cam-follower with three
links is suggested for this purpose. The kinematic analysis is carried
out and analysed using commercialized MATLAB software based on
the prototype-s links sizes and kinematic relationships. In order to
verify the kinematic analysis of the prototype, kinematic analysis data
are compared with the experimental data. A good agreement between
them proves that the anthropomorphic design of the lower extremity
exoskeleton follows the human walking gait.
Abstract: In this work we present some matrix operators named
circulant operators and their action on square matrices. This study on
square matrices provides new insights into the structure of the space
of square matrices. Moreover it can be useful in various fields as in
agents networking on Grid or large-scale distributed self-organizing
grid systems.
Abstract: In this work, a radial basis function (RBF) neural network is developed for the identification of hyperbolic distributed parameter systems (DPSs). This empirical model is based only on process input-output data and used for the estimation of the controlled variables at specific locations, without the need of online solution of partial differential equations (PDEs). The nonlinear model that is obtained is suitably transformed to a nonlinear state space formulation that also takes into account the model mismatch. A stable robust control law is implemented for the attenuation of external disturbances. The proposed identification and control methodology is applied on a long duct, a common component of thermal systems, for a flow based control of temperature distribution. The closed loop performance is significantly improved in comparison to existing control methodologies.
Abstract: The purpose of this research is to study motivation
factors and also to study factors relation to job performance to
compare motivation factors under the personal factor classification
such as gender, age, income, educational level, marital status, and
working duration; and to study the relationship between Motivation
Factors and Job Performance with job satisfactions. The sample
groups utilized in this research were 400 Suan Sunandha Rajabhat
University employees. This research is a quantitative research using
questionnaires as research instrument. The statistics applied for data
analysis including percentage, mean, and standard deviation. In
addition, the difference analysis was conducted by t value computing,
one-way analysis of variance and Pearson’s correlation coefficient
computing. The findings of the study results were as follows the
findings showed that the aspects of job promotion and salary were at
the moderate levels. Additionally, the findings also showed that the
motivations that affected the revenue branch chiefs’ job performance
were job security, job accomplishment, policy and management, job
promotion, and interpersonal relation.
Abstract: In the present work, the effective moisture diffusivity
and activation energy were calculated using an infinite series solution
of Fick-s diffusion equation. The results showed that increasing
drying temperature accelerated the drying process. All drying
experiments had only falling rate period. The average effective
moisture diffusivity values varied from 2.807x10-10 to 6.977x10-10m2
s_1 over the temperature and velocity range. The temperature
dependence of the effective moisture diffusivity for the thin layer
drying of the ginger slices was satisfactorily described by an
Arrhenius-type relationship with activation energy values of 19.313-
22.722 kJ.mol-1 within 40–70 °C and 0.8-3 ms-1 temperature range.
Abstract: In this paper, by using Mawhin-s continuation theorem of coincidence degree and a method based on delay differential inequality, some sufficient conditions are obtained for the existence and global exponential stability of periodic solutions of cellular neural networks with distributed delays and impulses on time scales. The results of this paper generalized previously known results.
Abstract: The process of wafer fabrication is arguably the most
technologically complex and capital intensive stage in semiconductor
manufacturing. This large-scale discrete-event process is highly reentrant,
and involves hundreds of machines, restrictions, and
processing steps. Therefore, production control of wafer fabrication
facilities (fab), specifically scheduling, is one of the most challenging
problems that this industry faces. Dispatching rules have been
extensively applied to the scheduling problems in semiconductor
manufacturing. Moreover, lot release policies are commonly used in
this manufacturing setting to further improve the performance of such
systems and reduce its inherent variability. In this work, simulation is
used in the scheduling of re-entrant flow shop manufacturing systems
with an application in semiconductor wafer fabrication; where, a
simulation model has been developed for the Intel Five-Machine Six
Step Mini-Fab using the ExtendTM simulation environment. The
Mini-Fab has been selected as it captures the challenges involved in
scheduling the highly re-entrant semiconductor manufacturing lines.
A number of scenarios have been developed and have been used to
evaluate the effect of different dispatching rules and lot release
policies on the selected performance measures. Results of simulation
showed that the performance of the Mini-Fab can be drastically
improved using a combination of dispatching rules and lot release
policy.
Abstract: A low cost Short Message System (SMS) based Home security system equipped with motion, smoke, temperature, humidity and light sensors has been studied and tested. The sensors are controlled by a microprocessor PIC 18F4520 through the SMS having password protection code for the secure operation. The user is able to switch light and the appliances and get instant feedback. Also in cases of emergencies such as fire or robbery the system will send alert message to occupant and relevant civil authorities. The operation of the home security has been tested on Vodafone- Fiji network and Digicel Fiji Network for emergency and feedback responses for 25 samples. The experiment showed that it takes about 8-10s for the security system to respond in case of emergency. It takes about 18-22s for the occupant to switch and monitor lights and appliances and then get feedback depending upon the network traffic.
Abstract: Software and applications are subjected to serious and damaging security threats, these threats are increasing as a result of increased number of potential vulnerabilities. Security testing is an indispensable process to validate software security requirements and to identify security related vulnerabilities. In this paper we analyze and compare different available vulnerabilities testing techniques based on a pre defined criteria using analytical hierarchy process (AHP). We have selected five testing techniques which includes Source code analysis, Fault code injection, Robustness, Stress and Penetration testing techniques. These testing techniques have been evaluated against five criteria which include cost, thoroughness, Ease of use, effectiveness and efficiency. The outcome of the study is helpful for researchers, testers and developers to understand effectiveness of each technique in its respective domain. Also the study helps to compare the inner working of testing techniques against a selected criterion to achieve optimum testing results.
Abstract: The modeling of water transfer in the unsaturated zone
uses techniques and methods of the soil physics to solve the
Richards-s equation. However, there is a disaccord between the size
of the measurements provided by the soil physics and the size of the
fields of hydrological modeling problem, to which is added the
strong spatial variability of soil hydraulic properties. The objective of
this work was to develop a methodology to estimate the
hydrodynamic parameters for modeling water transfers at different
hydrological scales in the soil-plant atmosphere systems.
Abstract: The purpose of this paper is to analyze the case of the
U.S. Pivot and to suggest an appropriate model including entry
strategies and success factors for QPS of Cable TV. The
telecommunication companies have been operating QPS including
IPTV service, which enables them to cross over broadcasting areas.
Due to this circumstance, the Cable TV operators are now concerned
and are planning to add QPS with the mobile service. Based on the
Porter's five forces model, an analytical framework has been proposed
to MVNO in Cable TV industry in the United States. As a result of this
study, MVNO in Cable TV industry has to have a clear killer
application with their sufficient contents. Subsequently, the direction
of the future Cable TV industry is proposed.
Abstract: The electrolyte stirring method of anodization etching
process for manufacturing porous silicon (PS) is reported in this work.
Two experimental setups of nature air stirring (PS-ASM) and
electrolyte stirring (PS-ESM) are employed to clarify the influence of
stirring mechanisms on electrochemical etching process. Compared to
traditional fabrication without any stirring apparatus (PS-TM), a large
plateau region of PS surface structure is obtained from samples with
both stirring methods by the 3D-profiler measurement. Moreover, the
light emission response is also improved by both proposed electrolyte
stirring methods due to the cycling force in electrolyte could
effectively enhance etch-carrier distribution while the electrochemical
etching process is made. According to the analysis of statistical
calculation of photoluminescence (PL) intensity, lower standard
deviations are obtained from PS-samples with studied stirring methods,
i.e. the uniformity of PL-intensity is effectively improved. The
calculated deviations of PL-intensity are 93.2, 74.5 and 64,
respectively, for PS-TM, PS-ASM and PS-ESM.
Abstract: The notion of communicative competence has been deemed fuzzy in communication studies. This fuzziness has led to tensions among engineers across tenures in interpreting what constitutes communicative competence. The study seeks to investigate novice and professional engineers- understanding of the said notion in terms of two main elements of communicative competence: linguistic and rhetorical competence. Novice engineers are final year engineering students, whilst professional engineers represent engineers who have at least 5 years working experience. Novice and professional engineers were interviewed to gauge their perceptions on linguistic and rhetorical features deemed necessary to enhance communicative competence for the profession. Both groups indicated awareness and differences on the importance of the sub-sets of communicative competence, namely, rhetorical explanatory competence, linguistic oral immediacy competence, technical competence and meta-cognitive competence. Such differences, a possible attribute of the learning theory, inadvertently indicate sublime differences in the way novice and professional engineers perceive communicative competence.
Abstract: Adolescents in Northern Uganda are at risk of teenage
pregnancies, unsafe abortions and sexually transmitted infections
(STIs). There is silence on sex both at home and school. This cross
sectional descriptive analytical study interviews a random sample of
827 students and 13 teachers on knowledge, perception and
acceptability to a comprehensive adolescent sexual and reproductive
health education in “O” and “A” level secondary schools in Gulu
District. Quantitative data was analyzed using SPSS 16.0. Directed
content analysis of themes of transcribed qualitative data was
conducted manually for common codes, sub-categories and
categories. Of the 827 students; 54.3% (449) reported being in a
sexual relationship especially those aged 15-17 years. Majority
96.1% (807) supported the teaching of a comprehensive ASRHE,
citing no negative impact 71.5% (601). Majority 81.6% (686) agreed
that such education could help prevention of STIs, abortions and
teenage pregnancies, and that it should be taught by health workers
69.0% (580). Majority 76.6% (203) reported that ASRHE was not
currently being taught in their schools. Students had low knowledge
levels and misconceptions about ASRHE. ASRHE was highly
acceptable though not being emphasized; its success in school
settings requires multidisciplinary culturally sensitive approaches
amongst which health workers should be frontiers.
Abstract: Among all mechanical joining processes, welding has
been employed for its advantage in design flexibility, cost saving,
reduced overall weight and enhanced structural performance.
However, for structures made of relatively thin components, welding
can introduce significant buckling distortion which causes loss of
dimensional control, structural integrity and increased fabrication
costs. Different parameters can affect buckling behavior of welded
thin structures such as, heat input, welding sequence, dimension of
structure. In this work, a 3-D thermo elastic-viscoplastic finite
element analysis technique is applied to evaluate the effect of shell
dimensions on buckling behavior and entropy generation of welded
thin shells. Also, in the present work, the approximated longitudinal
transient stresses which produced in each time step, is applied to the
3D-eigenvalue analysis to ratify predicted buckling time and
corresponding eigenmode. Besides, the possibility of buckling
prediction by entropy generation at each time is investigated and it is
found that one can predict time of buckling with drawing entropy
generation versus out of plane deformation. The results of finite
element analysis show that the length, span and thickness of welded
thin shells affect the number of local buckling, mode shape of global
buckling and post-buckling behavior of welded thin shells.
Abstract: This research work proposes a model of network security systems aiming to prevent production system in a data center from being attacked by intrusions. Conceptually, we introduce a decoy system as a part of the security system for luring intrusions, and apply network intrusion detection (NIDS), coupled with the decoy system to perform intrusion prevention. When NIDS detects an activity of intrusions, it will signal a redirection module to redirect all malicious traffics to attack the decoy system instead, and hence the production system is protected and safe. However, in a normal situation, traffic will be simply forwarded to the production system as usual. Furthermore, we assess the performance of the model with various bandwidths, packet sizes and inter-attack intervals (attacking frequencies).
Abstract: Today, the preferences and participation of the TD groups such as the elderly and disabled is still lacking in decision-making of transportation planning, and their reactions to certain type of policies are not well known. Thus, a clear methodology is needed. This study aimed to develop a method to extract the preferences of the disabled to be used in the policy-making stage that can also guide to future estimations. The method utilizes the combination of cluster analysis and data filtering using the data of the Arao city (Japan). The method is a process that follows: defining the TD group by the cluster analysis tool, their travel preferences in tabular form from the household surveys by policy variableimpact pairs, zones, and by trip purposes, and the final outcome is the preference probabilities of the disabled. The preferences vary by trip purpose; for the work trips, accessibility and transit system quality policies with the accompanying impacts of modal shifts towards public mode use as well as the decreasing travel costs, and the trip rate increase; for the social trips, the same accessibility and transit system policies leading to the same mode shift impact, together with the travel quality policy area leading to trip rate increase. These results explain the policies to focus and can be used in scenario generation in models, or any other planning purpose as decision support tool.
Abstract: A considerable progress has been achieved in transient
stability analysis (TSA) with various FACTS controllers. But, all
these controllers are associated with single transmission line. This
paper is intended to discuss a new approach i.e. a multi-line FACTS
controller which is interline power flow controller (IPFC) for TSA of
a multi-machine power system network. A mathematical model of
IPFC, termed as power injection model (PIM) presented and this
model is incorporated in Newton-Raphson (NR) power flow
algorithm. Then, the reduced admittance matrix of a multi-machine
power system network for a three phase fault without and with IPFC
is obtained which is required to draw the machine swing curves. A
general approach based on L-index has also been discussed to find
the best location of IPFC to reduce the proximity to instability of a
power system. Numerical results are carried out on two test systems
namely, 6-bus and 11-bus systems. A program in MATLAB has
been written to plot the variation of generator rotor angle and speed
difference curves without and with IPFC for TSA and also a simple
approach has been presented to evaluate critical clearing time for test
systems. The results obtained without and with IPFC are compared
and discussed.
Abstract: Cognitive radio devices have been considered as a key technology for next-generation of wireless communication. These devices in the context of IEEE 802.11 standards and IEEE 802.16 standards, can opportunistically utilize the wireless spectrum to achieve better user performance and improve the overall spectrumutilization efficiency, mainly in the unlicensed 5 GHz bands. However, opportunistic use of wireless spectrum creates news problems such as peaceful coexistence with other wireless technologies, such as the radiolocation systems, as well as understanding the influence of interference that each of these networks can create. In this paper, we suggest a dynamic access model that considerably reduces this interference and allows efficiency and fairness use of the wireless spectrum.