Abstract: Modeling of a heterogeneous industrial fixed bed
reactor for selective dehydrogenation of heavy paraffin with Pt-Sn-
Al2O3 catalyst has been the subject of current study. By applying
mass balance, momentum balance for appropriate element of reactor
and using pressure drop, rate and deactivation equations, a detailed
model of the reactor has been obtained. Mass balance equations have
been written for five different components. In order to estimate
reactor production by the passage of time, the reactor model which is
a set of partial differential equations, ordinary differential equations
and algebraic equations has been solved numerically.
Paraffins, olefins, dienes, aromatics and hydrogen mole percent as
a function of time and reactor radius have been found by numerical
solution of the model. Results of model have been compared with
industrial reactor data at different operation times. The comparison
successfully confirms validity of proposed model.
Abstract: Numerical simulations are performed for laminar
continuous and pulsed jets impinging on a surface in order to
investigate the effects of pulsing frequency on the heat transfer
characteristics. The time-averaged Nusselt number of pulsed jets is
larger in the impinging jet region as compared to the continuous jet,
while it is smaller in the outer wall jet region. At the stagnation point,
the mean and RMS Nusselt numbers become larger and smaller,
respectively, as the pulsing frequency increases. Unsteady behaviors
of vortical fluid motions and temperature field are also investigated to
understand the underlying mechanisms of heat transfer enhancement.
Abstract: This paper presents the impact study of GTO Controlled Series Capacitor (GCSC) parameters on measured impedance (Zseen) by MHO distance relays for single transmission line high voltage 220 kV in the presence of single phase to earth fault with fault resistance (RF). The study deals with a 220 kV single electrical transmission line of Eastern Algerian transmission networks at Group Sonelgaz (Algerian Company of Electrical and Gas) compensated by series Flexible AC Transmission System (FACTS) i.e. GCSC connected at midpoint of the transmission line. The transmitted active and reactive powers are controlled by three GCSC-s. The effects of maximum reactive power injected as well as injected maximum voltage by GCSC on distance relays measured impedance is treated. The simulations results investigate the effects of GCSC injected parameters: variable reactance (XGCSC), variable voltage (VGCSC) and reactive power injected (QGCSC) on measured resistance and reactance in the presence of earth fault with resistance fault varied between 5 to 50 Ω for three cases study.
Abstract: Risk of infectious disease outbreaks is related to the
hygiene among the population. To assess the actual risks and modify
the relevant emergency procedures if necessary, a hygiene survey
was conducted among undergraduate students on the Rhodes
University campus. Soap was available to 10.5% and only 26.8% of
the study participants followed proper hygiene in relation to food
consumption. This combination increases the risk of infectious
disease outbreaks at the campus. Around 83.6% were willing to wash
their hands if soap was provided. Procurement and availability of
soap in undergraduate residences on campus should be improved, as
the total cost is estimated at only 2000 USD per annum. Awareness
campaigns about food-related hygiene and the need for regular handwashing
with soap should be run among Rhodes University students.
If successful, rates of respiratory and hygiene-related diseases will be
decreased and emergency health management simplified.
Abstract: This paper presents results of empirical studies that were conducted in enterprises from Podkarpackie Voivodeship (Poland). It shows the experiences of those enterprises resulting from implementing and improving the eco-innovativeness management that is formal Environmental Management System (EMS). This study shows the expected and obtained internal benefits which are the effects of a functioning EMS. The aim of this paper is to determine whether the information included in international theoretical studies concerning the benefits of implementing, functioning and improving formal EMS (which is based on the international standard ISO 14001) are confirmed by the effects of the enterprises- activities.
Abstract: Today with the rapid growth of telecommunications equipment, electronic and developing more and more networks of power, influence of electromagnetic waves on one another has become hot topic discussions. So in this article, this issue and appropriate mechanisms for EMC operations have been presented. First, impact of high voltage lines on the surrounding environment especially on the control room has been investigated, then to reduce electromagnetic radiation, various methods of shielding are provided and shielding effectiveness of them has been compared. It should be expressed that simulations have been done by the finite element method (FEM).
Abstract: Information is increasing in volumes; companies are overloaded with information that they may lose track in getting the intended information. It is a time consuming task to scan through each of the lengthy document. A shorter version of the document which contains only the gist information is more favourable for most information seekers. Therefore, in this paper, we implement a text summarization system to produce a summary that contains gist information of oil and gas news articles. The summarization is intended to provide important information for oil and gas companies to monitor their competitor-s behaviour in enhancing them in formulating business strategies. The system integrated statistical approach with three underlying concepts: keyword occurrences, title of the news article and location of the sentence. The generated summaries were compared with human generated summaries from an oil and gas company. Precision and recall ratio are used to evaluate the accuracy of the generated summary. Based on the experimental results, the system is able to produce an effective summary with the average recall value of 83% at the compression rate of 25%.
Abstract: This paper describes the two actual tendencies in the
software development process usage: 'Scrum' and 'work in home
office'. It-s exposed the four main challenges to adopt Scrum
framework for distributed teams in this cited kind of work. The
challenges are mainly based on the communication problems due
distances since the Scrum encourages the team to work together in
the same room, and this is not possible when people work distributed
in their homes.
Abstract: Weather disaster events were frequent and caused loss
of lives and property in Taiwan recently. Excessive concentration of
population and lacking of integrated planning led to Taiwanese coastal
zone face the impacts of climate change directly. Comparing to many
countries which have already set up legislation, competent authorities
and national adaptation strategies, the ability of coastal management
adapting to climate change is still insufficient in Taiwan. Therefore, it
is necessary to establish a complete institutional arrangement for
coastal management due to climate change in order to protect
environment and sustain socio-economic development. This paper
firstly reviews the impact of climate change on Taiwanese coastal
zone. Secondly, development of Taiwanese institutional arrangement
of coastal management is introduced. Followed is the analysis of four
dimensions of legal basis, competent authority, scientific and financial
support and international cooperations of institutional arrangement.
The results show that Taiwanese government shall: 1) integrate climate
change issue into Coastal Act, Wetland Act and territorial planning
Act and pass them; 2) establish the high level competent authority for
coastal management; 3) set up the climate change disaster coordinate
platform; 4) link scientific information and decision markers; 5)
establish the climate change adjustment fund; 6) participate in
international climate change organizations and meetings actively; 7)
cooperate with near countries to exchange experiences.
Abstract: Synthesis gas manufacturing by steam reforming of hydrocarbons is an important industrial process. High endothermic nature of the process makes it one of the most cost and heat intensive processes. In the present work, composite effect of different inert gases on synthesis gas yield, feed gas conversion and temperature distribution along the reactor length has been studied using a heterogeneous model. Mathematical model was developed as a first stage and validated against the existing process models. With the addition of inert gases, a higher yield of synthesis gas is observed. Simultaneously the rector outlet temperature drops to as low as 810 K. It was found that Xenon gives the highest yield and conversion while Helium gives the lowest temperature. Using Xenon inert gas 20 percent reduction in outlet temperature was observed compared to traditional case.
Abstract: This paper presents two simplified models to
determine nodal voltages in power distribution networks. These
models allow estimating the impact of the installation of reactive
power compensations equipments like fixed or switched capacitor
banks. The procedure used to develop the models is similar to the
procedure used to develop linear power flow models of transmission
lines, which have been widely used in optimization problems of
operation planning and system expansion. The steady state non-linear
load flow equations are approximated by linear equations relating the
voltage amplitude and currents. The approximations of the linear
equations are based on the high relationship between line resistance
and line reactance (ratio R/X), which is valid for power distribution
networks. The performance and accuracy of the models are evaluated
through comparisons with the exact results obtained from the
solution of the load flow using two test networks: a hypothetical
network with 23 nodes and a real network with 217 nodes.
Abstract: Arms detection is one of the fundamental problems in
human motion analysis application. The arms are considered as the
most challenging body part to be detected since its pose and speed
varies in image sequences. Moreover, the arms are usually occluded
with other body parts such as the head and torso. In this paper,
histogram-based skin colour segmentation is proposed to detect the
arms in image sequences. Six different colour spaces namely RGB,
rgb, HSI, TSL, SCT and CIELAB are evaluated to determine the best
colour space for this segmentation procedure. The evaluation is
divided into three categories, which are single colour component,
colour without luminance and colour with luminance. The
performance is measured using True Positive (TP) and True Negative
(TN) on 250 images with manual ground truth. The best colour is
selected based on the highest TN value followed by the highest TP
value.
Abstract: A 10bit, 40 MSps, sample and hold, implemented in 0.18-μm CMOS technology with 3.3V supply, is presented for application in the front-end stage of an analog-to-digital converter. Topology selection, biasing, compensation and common mode feedback are discussed. Cascode technique has been used to increase the dc gain. The proposed opamp provides 149MHz unity-gain bandwidth (wu), 80 degree phase margin and a differential peak to peak output swing more than 2.5v. The circuit has 55db Total Harmonic Distortion (THD), using the improved fully differential two stage operational amplifier of 91.7dB gain. The power dissipation of the designed sample and hold is 4.7mw. The designed system demonstrates relatively suitable response in different process, temperature and supply corners (PVT corners).
Abstract: This paper describes a CMOS four-quadrant
multiplier intended for use in the front-end receiver by utilizing the
square-law characteristic of the MOS transistor in the saturation
region. The circuit is based on 0.35 um CMOS technology simulated
using HSPICE software. The mixer has a third-order inter the power
consumption is 271uW from a single 1.2V power supply. One of the
features of the proposed design is using two MOS transistors
limitation to reduce the supply voltage, which leads to reduce the
power consumption. This technique provides a GHz bandwidth
response and low power consumption.
Abstract: Choosing the right metadata is a critical, as good
information (metadata) attached to an image will facilitate its
visibility from a pile of other images. The image-s value is enhanced
not only by the quality of attached metadata but also by the technique
of the search. This study proposes a technique that is simple but
efficient to predict a single human image from a website using the
basic image data and the embedded metadata of the image-s content
appearing on web pages. The result is very encouraging with the
prediction accuracy of 95%. This technique may become a great
assist to librarians, researchers and many others for automatically and
efficiently identifying a set of human images out of a greater set of
images.
Abstract: The research objective of the project and article
“European Ecological Network Natura 2000 – opportunities and
threats” Natura 2000 sites constitute a form of environmental
protection, several legal problems are likely to result. Most
controversially, certain sites will be subject to two regimes of
protection: as national parks and as Natura 2000 sites. This dualism
of the legal regulation makes it difficult to perform certain legal
obligations related to the regimes envisaged under each form of
environmental protection. Which regime and which obligations
resulting from the particular form of environmental protection have
priority and should prevail? What should be done if these obligations
are contradictory? Furthermore, an institutional problem consists in
that no public administration authority has the power to resolve legal
conflicts concerning the application of a particular regime on a given
site. There are also no criteria to decide priority and superiority of
one form of environmental protection over the other. Which
regulations are more important, those that pertain to national parks or
to Natura 2000 sites? In the light of the current regulations, it is
impossible to give a decisive answer to these questions. The internal
hierarchy of forms of environmental protection has not been
determined, and all such forms should be treated equally.
Abstract: High speed networks provide realtime variable bit rate
service with diversified traffic flow characteristics and quality
requirements. The variable bit rate traffic has stringent delay and
packet loss requirements. The burstiness of the correlated traffic
makes dynamic buffer management highly desirable to satisfy the
Quality of Service (QoS) requirements. This paper presents an
algorithm for optimization of adaptive buffer allocation scheme for
traffic based on loss of consecutive packets in data-stream and buffer
occupancy level. Buffer is designed to allow the input traffic to be
partitioned into different priority classes and based on the input
traffic behavior it controls the threshold dynamically. This algorithm
allows input packets to enter into buffer if its occupancy level is less
than the threshold value for priority of that packet. The threshold is
dynamically varied in runtime based on packet loss behavior. The
simulation is run for two priority classes of the input traffic –
realtime and non-realtime classes. The simulation results show that
Adaptive Partial Buffer Sharing (ADPBS) has better performance
than Static Partial Buffer Sharing (SPBS) and First In First Out
(FIFO) queue under the same traffic conditions.
Abstract: The necessity of accurate and timely field data is
shared among organizations engaged in fundamentally different
activities, public services or commercial operations. Basically, there
are three major components in the process of the qualitative research:
data collection, interpretation and organization of data, and analytic
process. Representative technological advancements in terms of
innovation have been made in mobile devices (mobile phone, PDA-s,
tablets, laptops, etc). Resources that can be potentially applied on the
data collection activity for field researches in order to improve this
process.
This paper presents and discuss the main features of a mobile
phone based solution for field data collection, composed of basically
three modules: a survey editor, a server web application and a client
mobile application. The data gathering process begins with the
survey creation module, which enables the production of tailored
questionnaires. The field workforce receives the questionnaire(s) on
their mobile phones to collect the interviews responses and sending
them back to a server for immediate analysis.
Abstract: In this paper, we propose a Perceptually Optimized Foveation based Embedded ZeroTree Image Coder (POEFIC) that introduces a perceptual weighting to wavelet coefficients prior to control SPIHT encoding algorithm in order to reach a targeted bit rate with a perceptual quality improvement with respect to a given bit rate a fixation point which determines the region of interest ROI. The paper also, introduces a new objective quality metric based on a Psychovisual model that integrates the properties of the HVS that plays an important role in our POEFIC quality assessment. Our POEFIC coder is based on a vision model that incorporates various masking effects of human visual system HVS perception. Thus, our coder weights the wavelet coefficients based on that model and attempts to increase the perceptual quality for a given bit rate and observation distance. The perceptual weights for all wavelet subbands are computed based on 1) foveation masking to remove or reduce considerable high frequencies from peripheral regions 2) luminance and Contrast masking, 3) the contrast sensitivity function CSF to achieve the perceptual decomposition weighting. The new perceptually optimized codec has the same complexity as the original SPIHT techniques. However, the experiments results show that our coder demonstrates very good performance in terms of quality measurement.
Abstract: The increased number of automobiles in recent years
has resulted in great demand for fossil fuel. This has led to the
development of automobile by using alternative fuels which include
gaseous fuels, biofuels and vegetables oils as fuel. Energy from
biomass and more specific bio-diesel is one of the opportunities that
could cover the future demand of fossil fuel shortage. Biomass in the
form of cashew nut shell represents a new energy source and
abundant source of energy in India. The bio-fuel is derived from
cashew nut shell oil and its blend with diesel are promising
alternative fuel for diesel engine. In this work the pyrolysis Cashew
Nut Shell Liquid (CNSL)-Diesel Blends (CDB) was used to run the
Direct Injection (DI) diesel engine. The experiments were conducted
with various blends of CNSL and Diesel namely B20, B40, B60, B80
and B100. The results are compared with neat diesel operation. The
brake thermal efficiency was decreased for blends of CNSL and
Diesel except the lower blends of B20. The brake thermal efficiency
of B20 is nearly closer to that of diesel fuel. Also the emission level
of the all CNSL and Diesel blends was increased compared to neat
diesel. The higher viscosity and lower volatility of CNSL leads to
poor mixture formation and hence lower brake thermal efficiency and
higher emission levels. The higher emission level can be reduced by
adding suitable additives and oxygenates with CNSL and Diesel
blends.