Abstract: In this paper, based on flume experimental data, the velocity distribution in open channel flows is re-investigated. From the analysis, it is proposed that the wake layer in outer region may be divided into two regions, the relatively weak outer region and the relatively strong outer region. Combining the log law for inner region and the parabolic law for relatively strong outer region, an explicit equation for mean velocity distribution of steady and uniform turbulent flow through straight open channels is proposed and verified with the experimental data. It is found that the sediment concentration has significant effect on velocity distribution in the relatively weak outer region.
Abstract: Hysteresis phenomenon has been observed in the
operations of both horizontal-axis and vertical-axis wind turbines
(HAWTs and VAWTs). In this study, wind tunnel experiments were
applied to investigate the characters of hysteresis phenomena between
the angular speed and the external resistance of electrical loading
during the operation of a Darrieus type VAWT. Data of output voltage,
output current, angular speed of wind turbine under different wind
speeds are measured and analyzed. Results show that the range of
external resistance changes with the wind speed. The range decreases
as the wind speed increases following an exponential decay form.
Experiments also indicate that the maximum output power of wind
turbines is always inside the range where hysteresis happened. These
results provide an important reference to the design of output control
system of wind turbines.
Abstract: The game of Maundy Block is the three-player variant
of Maundy Cake, a classical combinatorial game. Even though to
determine the solution of Maundy Cake is trivial, solving Maundy
Block is challenging because of the identification of queer games,
i.e., games where no player has a winning strategy.
Abstract: This paper addresses an efficient technique to embed and detect digital fingerprint code. Orthogonal modulation method is a straightforward and widely used approach for digital fingerprinting but shows several limitations in computational cost and signal efficiency. Coded modulation method can solve these limitations in theory. However it is difficult to perform well in practice if host signals are not available during tracing colluders, other kinds of attacks are applied, and the size of fingerprint code becomes large. In this paper, we propose a hybrid modulation method, in which the merits of or-thogonal modulation and coded modulation method are combined so that we can achieve low computational cost and high signal efficiency. To analyze the performance, we design a new fingerprint code based on GD-PBIBD theory and modulate this code into images by our method using spread-spectrum watermarking on frequency domain. The results show that the proposed method can efficiently handle large fingerprint code and trace colluders against averaging attacks.
Abstract: Increasing growth of information volume in the
internet causes an increasing need to develop new (semi)automatic
methods for retrieval of documents and ranking them according to
their relevance to the user query. In this paper, after a brief review
on ranking models, a new ontology based approach for ranking
HTML documents is proposed and evaluated in various
circumstances. Our approach is a combination of conceptual,
statistical and linguistic methods. This combination reserves the
precision of ranking without loosing the speed. Our approach
exploits natural language processing techniques for extracting
phrases and stemming words. Then an ontology based conceptual
method will be used to annotate documents and expand the query.
To expand a query the spread activation algorithm is improved so
that the expansion can be done in various aspects. The annotated
documents and the expanded query will be processed to compute
the relevance degree exploiting statistical methods. The outstanding
features of our approach are (1) combining conceptual, statistical
and linguistic features of documents, (2) expanding the query with
its related concepts before comparing to documents, (3) extracting
and using both words and phrases to compute relevance degree, (4)
improving the spread activation algorithm to do the expansion based
on weighted combination of different conceptual relationships and
(5) allowing variable document vector dimensions. A ranking
system called ORank is developed to implement and test the
proposed model. The test results will be included at the end of the
paper.
Abstract: Conventional approaches in the implementation of logic programming applications on embedded systems are solely of software nature. As a consequence, a compiler is needed that transforms the initial declarative logic program to its equivalent procedural one, to be programmed to the microprocessor. This approach increases the complexity of the final implementation and reduces the overall system's performance. On the contrary, presenting hardware implementations which are only capable of supporting logic programs prevents their use in applications where logic programs need to be intertwined with traditional procedural ones, for a specific application. We exploit HW/SW codesign methods to present a microprocessor, capable of supporting hybrid applications using both programming approaches. We take advantage of the close relationship between attribute grammar (AG) evaluation and knowledge engineering methods to present a programmable hardware parser that performs logic derivations and combine it with an extension of a conventional RISC microprocessor that performs the unification process to report the success or failure of those derivations. The extended RISC microprocessor is still capable of executing conventional procedural programs, thus hybrid applications can be implemented. The presented implementation is programmable, supports the execution of hybrid applications, increases the performance of logic derivations (experimental analysis yields an approximate 1000% increase in performance) and reduces the complexity of the final implemented code. The proposed hardware design is supported by a proposed extended C-language called C-AG.
Abstract: Global climate change has become the preeminent
threat to human security in the 21st century. From mitigation perspective, this study aims to evaluate the performance of biogas
renewable project under clean development mechanism activities
(namely Korat-Waste-to-Energy) in Thailand and to assess local perceptions towards the significance of climate change mitigation and
sustainability of such project in their community. Questionnaire was
developed based on the national sustainable development criteria and
was distributed among systematically selected households within
project boundaries (n=260). Majority of the respondents strongly agreed with the reduction of odor problems (81%) and air pollution
(76%). However, they were unsure about greenhouse gas reduction from such project and ignorant about the key issues of climate change. A lesson learned suggested that there is a need to further
investigate the possible socio-psychological barriers may significantly shape public perception and understandings of climate
change in the local context.
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: Dynamic of phytoplankton blooms in the Baltic Sea
has been analyzed applying the numerical ecosystem model 3D
CEMBS. The model consists of the hydrodynamic model (POP,
version 2.1) and the ice model (CICE, version 4.0), which are
imposed by the atmospheric data model (DATM7). The 3D
model has an ecosystem module, activated in 2012 in the operational
mode. The ecosystem model consists of 11 main variables: biomass
of small-size phytoplankton and large-size phytoplankton
and cyanobacteria, zooplankton biomass, dissolved and molecular
detritus, dissolved oxygen concentration, as well as concentrations of
nutrients, including: nitrates, ammonia, phosphates and silicates. The
3D-CEMBS model is an effective tool for solving problems related to
phytoplankton blooms dynamic in the Baltic Sea
Abstract: Full adders are important components in applications
such as digital signal processors (DSP) architectures and
microprocessors. In addition to its main task, which is adding two
numbers, it participates in many other useful operations such as
subtraction, multiplication, division,, address calculation,..etc. In
most of these systems the adder lies in the critical path that
determines the overall speed of the system. So enhancing the
performance of the 1-bit full adder cell (the building block of the
adder) is a significant goal.Demands for the low power VLSI have
been pushing the development of aggressive design methodologies to
reduce the power consumption drastically. To meet the growing
demand, we propose a new low power adder cell by sacrificing the
MOS Transistor count that reduces the serious threshold loss
problem, considerably increases the speed and decreases the power
when compared to the static energy recovery full (SERF) adder. So a
new improved 14T CMOS l-bit full adder cell is presented in this
paper. Results show 50% improvement in threshold loss problem,
45% improvement in speed and considerable power consumption
over the SERF adder and other different types of adders with
comparable performance.
Abstract: Despite the availability of natural disaster related time series data for last 110 years, there is no forecasting tool available to humanitarian relief organizations to determine forecasts for emergency logistics planning. This study develops a forecasting tool based on identifying probability distributions. The estimates of the parameters are used to calculate natural disaster forecasts. Further, the determination of aggregate forecasts leads to efficient pre-disaster planning. Based on the research findings, the relief agencies can optimize the various resources allocation in emergency logistics planning.
Abstract: Since 1992, year where Hugo de Garis has published
the first paper on Evolvable Hardware (EHW), a period of intense
creativity has followed. It has been actively researched, developed
and applied to various problems. Different approaches have been
proposed that created three main classifications: extrinsic, mixtrinsic
and intrinsic EHW. Each of these solutions has a real interest.
Nevertheless, although the extrinsic evolution generates some
excellent results, the intrinsic systems are not so advanced. This
paper suggests 3 possible solutions to implement the run-time
configuration intrinsic EHW system: FPGA-based Run-Time
Configuration system, JBits-based Run-Time Configuration system
and Multi-board functional-level Run-Time Configuration system.
The main characteristic of the proposed architectures is that they are
implemented on Field Programmable Gate Array. A comparison of
proposed solutions demonstrates that multi-board functional-level
run-time configuration is superior in terms of scalability, flexibility
and the implementation easiness.
Abstract: In this paper, a fibre laser at 546 nm has been studied
for a signal power of -30 dB. Er3+-doped ZBLAN fibre has been used
by upconversion pumping of a 980 nm laser diode. Gain saturation
effect has been investigated in detail. Laser performance has also been
discussed. An efficiency of 35% has been calculated with a length of 5
mm fibre laser. Results show that Er3+-doped ZBLAN is a promising
candidate for optical amplification at 546 nm.
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: Effects of bio-nitrogen fertilizer (bio-N), as a partial
alternative to mineral-nitrogen fertilizer (mineral-N), on growth,
yield and yield quality of broccoli plants were investigated. Bio-N
was applied at 1, 2 or 3 doses in combination with 65% of the
recommended dose of mineral-N (bio-N1, bio-N2 or bio-N3 +
⅔mineral-N). However, 100% of the recommended dose of mineral-
N was applied as a control. Significant positive influences of the bio-
N3 + ⅔mineral-N treatment were observed on growth traits, leaf
contents of nitrogen, phosphorus, potassium, nitrate and nitrite, and
yield quality when compared to the other two combined treatments.
In contrast, there were no significant differences in these parameters
between the bio-N3 + ⅔mineral-N and the control treatments, except
for leaf contents of nitrate and nitrite. They showed lower contents in
the bio-N3 + ⅔mineral-N treatment than the control. Therefore, we
recommend using bio-N as a partial alternative to mineral-N for
healthy nutrition.
Abstract: Repeated observation of a given area over time yields
potential for many forms of change detection analysis. These
repeated observations are confounded in terms of radiometric
consistency due to changes in sensor calibration over time,
differences in illumination, observation angles and variation in
atmospheric effects.
This paper demonstrates applicability of an empirical relative
radiometric normalization method to a set of multitemporal cloudy
images acquired by Resourcesat1 LISS III sensor. Objective of this
study is to detect and remove cloud cover and normalize an image
radiometrically. Cloud detection is achieved by using Average
Brightness Threshold (ABT) algorithm. The detected cloud is
removed and replaced with data from another images of the same
area. After cloud removal, the proposed normalization method is
applied to reduce the radiometric influence caused by non surface
factors. This process identifies landscape elements whose reflectance
values are nearly constant over time, i.e. the subset of non-changing
pixels are identified using frequency based correlation technique. The
quality of radiometric normalization is statistically assessed by R2
value and mean square error (MSE) between each pair of analogous
band.
Abstract: Malaria is transmitted to the human by biting of
infected Anopheles mosquitoes. This disease is a serious, acute and
chronic relapsing infection to humans. Fever, nausea, vomiting, back
pain, increased sweating anemia and splenomegaly (enlargement of
the spleen) are the symptoms of the patients who infected with this
disease. It is caused by the multiplication of protozoa parasite of the
genus Plasmodium. Plasmodium falciparum, Plasmodium vivax,
Plasmodium malariae and Plasmodium ovale are the four types of
Plasmodium malaria. A mathematical model for the transmission of
Plasmodium Malaria is developed in which the human and vector
population are divided into two classes, the susceptible and the
infectious classes. In this paper, we formulate the dynamical model
of Plasmodium falciparum and Plasmodium vivax malaria. The
standard dynamical analysis is used for analyzing the behavior for
the transmission of this disease. The Threshold condition is found
and numerical results are shown to confirm the analytical results.
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.