Abstract: Providing authentication for the messages exchanged
between group members in addition to confidentiality is an important
issue in Secure Group communication. We develop a protocol for
Secure Authentic Communication where we address authentication
for the group communication scheme proposed by Blundo et al.
which only provides confidentiality. Authentication scheme used is a
multiparty authentication scheme which allows all the users in the
system to send and receive messages simultaneously. Our scheme is
secure against colluding malicious parties numbering fewer than k.
Abstract: Phase error in communications systems degrades error
performance. In this paper, we present a simple approximation for the
average error probability of the binary phase shift keying (BPSK) in
the presence of phase error having a uniform distribution on arbitrary
intervals. For the simple approximation, we use symmetry and
periodicity of a sinusoidal function. Approximate result for the
average error probability is derived, and the performance is verified
through comparison with simulation result.
Abstract: Adapting wireless devices to communicate within grid
networks empowers us by providing range of possibilities.. These
devices create a mechanism for consumers and publishers to create
modern networks with or without peer device utilization. Emerging
mobile networks creates new challenges in the areas of reliability,
security, and adaptability. In this paper, we propose a system
encompassing mobility management using AAA context transfer for
mobile grid networks. This system ultimately results in seamless task
processing and reduced packet loss, communication delays,
bandwidth, and errors.
Abstract: Cooling with sound is a physical phenomenon allowed by Thermo-Acoustics in which acoustic energy is transformed into a negative heat transfer, in other words: into cooling! Without needing any harmful gas, the transformation is environmentally friendly and can respond to many needs in terms of air conditioning, food refrigeration for domestic use, and cooling medical samples for example. To explore the possibilities of this cooling solution on a small scale, the TACS prototype has been designed, consisting of a low cost thermoacoustic refrigerant “pipe” able to lower the temperature by a few degrees. The obtained results are providing an interesting element for possible future of thermo-acoustic refrigeration.
Abstract: In this paper a computer system for electromagnetic
properties measurements is designed. The system employs Agilent
4294A precision impedance analyzer to measure the amplitude and
the phase of a signal applied over a tested biological tissue sample.
Measured by the developed computer system data could be used for
tissue characterization in wide frequency range from 40Hz to
110MHz. The computer system can interface with output devices
acquiring flexible testing process.
Abstract: Development of a Robust Supply Chain for Dynamic
Operating Environment as we move further into the twenty first
century, organisations are under increasing pressure to deliver a high
product variation at a reasonable cost without compromise in quality.
In a number of cases this will take the form of a customised or high
variety low volume manufacturing system that requires prudent
management of resources, among a number of functions, to achieve
competitive advantage. Purchasing and Supply Chain management is
one of such function and due to the substantial interaction with
external elements needs to be strategically managed. This requires a
number of primary and supporting tools that will enable the
appropriate decisions to be made rapidly. This capability is
especially vital in a dynamic environment as it provides a pivotal role
in increasing the profit margin of the product. The management of
this function can be challenging by itself and even more for Small
and Medium Enterprises (SMEs) due to the limited resources and
expertise available at their disposal.
This paper discusses the development of tools and concepts
towards effectively managing the purchasing and supply chain
function. The developed tools and concepts will provide a cost
effective way of managing this function within SMEs. The paper
further shows the use of these tools within Contechs, a manufacturer
of luxury boat interiors, and the associated benefits achieved as a
result of this implementation. Finally a generic framework towards
use in such environments is presented.
Abstract: Directive 2009/28/CE establishes, as obligatory objective, a share of renewable energies on energetic consumption of 20%, in European Union, in 2020 However, such European normative gives freedom to member states in the selection of the renewable promotion mechanism that allows them to obtain that objective. In this paper, we analyze the main characteristics of the promotion mechanisms of renewable energy used in the countries that shape the Electricity Iberian Market (Spain and Portugal) and the results in employment. The importance of these countries is given by the great increasing of the renewable energies which suppose a share higher than 30% of the overall generation in 2010. Therefore, this research paper can serve as the basis for the learning of other countries with regard to the main advantages that entail the use of a feed-in tariff system.
Abstract: There are several ways of improving the performance of a vapor compression refrigeration cycle. Use of an ejector as expansion device is one of the alternative ways. The present paper aims at evaluate the performance improvement of a vapor compression refrigeration cycle under a wide range of operating conditions. A numerical model is developed and a parametric study of important parameters such as condensation (30-50°C) and evaporation temperatures (-20-5°C), nozzle and diffuser efficiencies (0.75-0.95), subcooling and superheating degrees (0-15K) are investigated. The model verification gives a good agreement with the literature data. The simulation results revealed that condensation temperature has the highest effect (129%) on the performance improvement ratio while superheating has the lowest one (6.2%). Among ejector efficiencies, the diffuser efficiency has a significant effect on the COP of ejector expansion refrigeration cycle. The COP improvement percentage decreases from 10.9% to 4.6% as subcooling degrees increases by 15K.
Abstract: Orthogonal Frequency Division Multiplexing (OFDM) is one of the techniques for high speed data rate communication with main consideration for 4G and 5G systems. In OFDM, there are several mapping schemes which provide a way of parallel transmission. In this paper, comparisons of mapping schemes used by some standards have been made and also has been discussed about the performance of the non-conventional modulation technique. The Comparisons of Bit Error Rate (BER) performances for conventional and non-conventional modulation schemes have been done using MATLAB software. Mentioned schemes used in OFDM system can be selected on the basis of the requirement of power or spectrum efficiency and BER analysis.
Abstract: Ant colony optimization is an ant algorithm framework that took inspiration from foraging behavior of ant colonies. Indeed, ACO algorithms use a chemical communication, represented by pheromone trails, to build good solutions. However, ants involve different communication channels to interact. Thus, this paper introduces the acoustic communication between ants while they are foraging. This process allows fine and local exploration of search space and permits optimal solution to be improved.
Abstract: In this paper we propose a novel Run Time Interface
(RTI) technique to provide an efficient environment for MPI jobs on
the heterogeneous architecture of PARAM Padma. It suggests an
innovative, unified framework for the job management interface
system in parallel and distributed computing. This approach employs
proxy scheme. The implementation shows that the proposed RTI is
highly scalable and stable. Moreover RTI provides the storage access
for the MPI jobs in various operating system platforms and improve
the data access performance through high performance C-DAC
Parallel File System (C-PFS). The performance of the RTI is
evaluated by using the standard HPC benchmark suites and the
simulation results show that the proposed RTI gives good
performance on large scale supercomputing system.
Abstract: Modeling of complex dynamic systems, which are
very complicated to establish mathematical models, requires new and
modern methodologies that will exploit the existing expert
knowledge, human experience and historical data. Fuzzy cognitive
maps are very suitable, simple, and powerful tools for simulation and
analysis of these kinds of dynamic systems. However, human experts
are subjective and can handle only relatively simple fuzzy cognitive
maps; therefore, there is a need of developing new approaches for an
automated generation of fuzzy cognitive maps using historical data.
In this study, a new learning algorithm, which is called Big Bang-Big
Crunch, is proposed for the first time in literature for an automated
generation of fuzzy cognitive maps from data. Two real-world
examples; namely a process control system and radiation therapy
process, and one synthetic model are used to emphasize the
effectiveness and usefulness of the proposed methodology.
Abstract: The goal of speech parameterization is to extract the relevant information about what is being spoken from the audio signal. In speech recognition systems Mel-Frequency Cepstral Coefficients (MFCC) and Relative Spectral Mel-Frequency Cepstral Coefficients (RASTA-MFCC) are the two main techniques used. It will be shown in this paper that it presents some modifications to the original MFCC method. In our work the effectiveness of proposed changes to MFCC called Modified Function Cepstral Coefficients (MODFCC) were tested and compared against the original MFCC and RASTA-MFCC features. The prosodic features such as jitter and shimmer are added to baseline spectral features. The above-mentioned techniques were tested with impulsive signals under various noisy conditions within AURORA databases.
Abstract: This paper presents a distributed intrusion
detection system IDS, based on the concept of specialized
distributed agents community representing agents with the
same purpose for detecting distributed attacks. The semantic of
intrusion events occurring in a predetermined network has been
defined. The correlation rules referring the process which our
proposed IDS combines the captured events that is distributed
both spatially and temporally. And then the proposed IDS tries
to extract significant and broad patterns for set of well-known
attacks. The primary goal of our work is to provide intrusion
detection and real-time prevention capability against insider
attacks in distributed and fully automated environments.
Abstract: Purpose of this work is the development of an
automatic classification system which could be useful for radiologists
in the investigation of breast cancer. The software has been designed
in the framework of the MAGIC-5 collaboration.
In the automatic classification system the suspicious regions with
high probability to include a lesion are extracted from the image as
regions of interest (ROIs). Each ROI is characterized by some
features based on morphological lesion differences.
Some classifiers as a Feed Forward Neural Network, a K-Nearest
Neighbours and a Support Vector Machine are used to distinguish the
pathological records from the healthy ones.
The results obtained in terms of sensitivity (percentage of
pathological ROIs correctly classified) and specificity (percentage of
non-pathological ROIs correctly classified) will be presented through
the Receive Operating Characteristic curve (ROC). In particular the
best performances are 88% ± 1 of area under ROC curve obtained
with the Feed Forward Neural Network.
Abstract: Ultrafast doped zinc oxide crystal promised us a good
opportunity to build new instruments for ICF fusion neutron
measurement. Two pulsed neutron detectors based on ZnO crystal
wafer have been conceptually designed, the superfast ZnO timing
detector and the scintillation recoil proton neutron detection system.
The structure of these detectors was presented, and some characters
were studied as well. The new detectors could be much faster than
existing systems, and would be more competent for ICF neutron
diagnostics.
Abstract: Efficient modulo 2n+1 adders are important for
several applications including residue number system, digital signal
processors and cryptography algorithms. In this paper we present a
novel modulo 2n+1 addition algorithm for a recently represented
number system. The proposed approach is introduced for the
reduction of the power dissipated. In a conventional modulo 2n+1
adder, all operands have (n+1)-bit length. To avoid using (n+1)-bit
circuits, the diminished-1 and carry save diminished-1 number
systems can be effectively used in applications. In the paper, we also
derive two new architectures for designing modulo 2n+1 adder, based
on n-bit ripple-carry adder. The first architecture is a faster design
whereas the second one uses less hardware. In the proposed method,
the special treatment required for zero operands in Diminished-1
number system is removed. In the fastest modulo 2n+1 adders in
normal binary system, there are 3-operand adders. This problem is
also resolved in this paper. The proposed architectures are compared
with some efficient adders based on ripple-carry adder and highspeed
adder. It is shown that the hardware overhead and power
consumption will be reduced. As well as power reduction, in some
cases, power-delay product will be also reduced.
Abstract: Wireless Sensor Network is Multi hop Self-configuring
Wireless Network consisting of sensor nodes. The deployment of
wireless sensor networks in many application areas, e.g., aggregation
services, requires self-organization of the network nodes into clusters.
Efficient way to enhance the lifetime of the system is to partition the
network into distinct clusters with a high energy node as cluster head.
The different methods of node clustering techniques have appeared in
the literature, and roughly fall into two families; those based on the
construction of a dominating set and those which are based solely on
energy considerations. Energy optimized cluster formation for a set
of randomly scattered wireless sensors is presented. Sensors within a
cluster are expected to be communicating with cluster head only. The
energy constraint and limited computing resources of the sensor nodes
present the major challenges in gathering the data. In this paper we
propose a framework to study how partially correlated data affect the
performance of clustering algorithms. The total energy consumption
and network lifetime can be analyzed by combining random geometry
techniques and rate distortion theory. We also present the relation
between compression distortion and data correlation.
Abstract: The hard clam (meretrix lusoria) cultivated industry
has been developed vigorously for recent years in Taiwan, and
seawater quality determines the cultivated environment. The pH
concentration variation affects survival rate of meretrix lusoria
immediately. In order to monitor seawater quality, solid-state sensing
electrode of ruthenium-doped titanium dioxide (TiO2:Ru) is developed
to measure hydrogen ion concentration in different cultivated
solutions. Because the TiO2:Ru sensing electrode has high chemical
stability and superior sensing characteristics, thus it is applied as a pH
sensor. Response voltages of TiO2:Ru sensing electrode are readout by
instrument amplifier in different sample solutions. Mean sensitivity
and linearity of TiO2:Ru sensing electrode are 55.20 mV/pH and 0.999
from pH1 to pH13, respectively. We expect that the TiO2:Ru sensing
electrode can be applied to real environment measurement, therefore
we collect two sample solutions by different meretrix lusoria
cultivated ponds in the Yunlin, Taiwan. The two sample solutions are
both measured for 200 seconds after calibration of standard pH buffer
solutions (pH7, pH8 and pH 9). Mean response voltages of sample 1
and sample 2 are -178.758 mV (Standard deviation=0.427 mV) and
-180.206 mV (Standard deviation =0.399 mV), respectively. Response
voltages of the two sample solutions are between pH 8 and pH 9 which
conform to weak alkali range and suitable meretrix lusoria growth. For
long-term monitoring, drift of cultivated solutions (sample 1 and
sample 2) are 1.16 mV/hour and 1.03 mV/hour, respectively.
Abstract: Recently ORC(Organic Rankine Cycle) has attracted
much attention due to its potential in reducing consumption of fossil
fuels and its favorable characteristics to exploit low-grade heat sources.
In this work thermodynamic performance of ORC with superheating of
vapor is comparatively assessed for various working fluids. Special
attention is paid to the effects of system parameters such as the evaporating
temperature and the turbine inlet temperature on the characteristics
of the system such as maximum possible work extraction from
the given source, volumetric flow rate per 1 kW of net work and
quality of the working fluid at turbine exit as well as thermal and
exergy efficiencies. Results show that for a given source the thermal
efficiency increases with decrease of the superheating but exergy
efficiency may have a maximum value with respect to the superheating
of the working fluid. Results also show that in selection of working
fluid it is required to consider various criteria of performance characteristics
as well as thermal efficiency.