Abstract: Stegnography is a new way of secret
communication the most widely used mechanism on account
of its simplicity is the use of the least significant bit. We have
used the least significant bit (2 LSB and 4 LSB) substitution
method. Depending upon the characteristics of the individual
portions of cover image we decide whether to use 2 LSB or 4
LSB thus it is an adaptive stegnography technique. We used
one of the three channels to behave as indicator to indicate the
presence of hidden data in other two channels. The module
showed impressive results in terms of capacity to hide the
data. In proposed method, instead of using RGB color space
directly, YCbCr color space is used to make use of human
visual system characteristic.
Abstract: The motion planning procedure described in this paper has been developed in order to eliminate or reduce the residual vibrations of electromechanical positioning systems, without augmenting the motion time (usually imposed by production requirements), nor introducing overtime for vibration damping. The proposed technique is based on a suitable choice of the motion law assigned to the servomotor that drives the mechanism. The reference profile is defined by a Bezier curve, whose shape can be easily changed by modifying some numerical parameters. By means of an optimization technique these parameters can be modified without altering the continuity conditions imposed on the displacement and on its time derivatives at the initial and final time instants.
Abstract: Since Network-on-Chip (NoC) uses network
interfaces (NIs) to improve the design productivity, by now, there
have been a few papers addressing the design and implementation of a
NI module. However, none of them considered the difference of
address encoding methods between NoC and the traditional
bus-shared architecture. On the basis of this difference, in the paper,
we introduce a transmit mechanism to solve such a problem for global
asynchronous locally synchronous (GALS) NoC. Furthermore, we
give the concrete implementation of the NI module in this transmit
mechanism. Finally, we evaluate its performance and area overhead
by a VHDL-based cycle-accurate RTL model and simulation results
confirm the validity of this address-oriented transmit mechanism.
Abstract: The waves of eGovernment are rising very fast
through almost all public administration, or at least most of the
public administrations around the world, and not only the public
administration, but also the entire government and all of their
organization as a whole. The government uses information
technology, and above all the internet or web network, to facilitate
the exchange of services between government agencies and citizens,
businesses, employees and other non-governmental agencies. With
efficient and transparent information exchange, the information
becomes accessible to the society (citizens, business, employees etc.),
and as a result of these processes the society itself becomes the
information society or knowledge society. This paper discusses the
knowledge management for eGovernment development in
significance and role. Also, the paper reviews the role of virtual
communities as a knowledge management mechanism to support
eGovernment in Montenegro. It explores the need for knowledge
management in eGovernment, identifies knowledge management
technologies, and highlights the challenges for developing countries,
such as Montenegro in the implementation of eGovernment. The
paper suggests that knowledge management is needed to facilitate
information exchange and transaction processing with citizens, as
well as to enable creation of knowledge society.
Abstract: In this paper, a uniform calculus-based approach for
synthesizing monitors checking correctness properties specified by a
large variety of logics at runtime is provided, including future and past
time logics, interval logics, state machine and parameterized temporal
logics. We present a calculus mechanism to synthesize monitors from
the logical specification for the incremental analysis of execution
traces during test and real run. The monitor detects both good and bad
prefix of a particular kind, namely those that are informative for the
property under investigation. We elaborate the procedure of calculus
as monitors.
Abstract: The Taiwan government has started to promote the “Plain Landscape Afforestation and Greening Program" since 2002. A key task of the program was the payment for environmental services (PES), entitled the “Plain Landscape Afforestation Policy" (PLAP), which was certificated by the Executive Yuan on August 31, 2001 and enacted on January 1, 2002. According to the policy, it is estimated that the total area of afforestation will be 25,100 hectares by December 31, 2007. Until the end of 2007, the policy had been enacted for six years in total and the actual area of afforestation was 8,919.18 hectares. Among them, Taiwan Sugar Corporation (TSC) was accounted for 7,960 hectares (with 2,450.83 hectares as public service area) which occupied 86.22% of the total afforestation area; the private farmland promoted by local governments was accounted for 869.18 hectares which occupied 9.75% of the total afforestation area. Based on the above, we observe that most of the afforestation area in this policy is executed by TSC, and the achievement ratio by TSC is better than by others. It implies that the success of the PLAP is seriously related to the execution of TSC. The objective of this study is to analyze the relevant policy planning of TSC's participation in the PLAP, suggest complementary measures, and draw up effective adjustment mechanisms, so as to improve the effectiveness of executing the policy. Our main conclusions and suggestions are summarized as follows: 1. The main reason for TSC’s participation in the PLAP is based on their passive cooperation with the central government or company policy. Prior to TSC’s participation in the PLAP, their lands were mainly used for growing sugarcane. 2. The main factors of TSC's consideration on the selection of tree species are based on the suitability of land and species. The largest proportion of tree species is allocated to economic forests, and the lack of technical instruction was the main problem during afforestation. Moreover, the method of improving TSC’s future development in leisure agriculture and landscape business becomes a key topic. 3. TSC has developed short and long-term plans on participating in the PLAP for the future. However, there is no great willingness or incentive on budgeting for such detailed planning. 4. Most people from TSC interviewed consider the requirements on PLAP unreasonable. Among them, an unreasonable requirement on the number of trees accounted for the greatest proportion; furthermore, most interviewees suggested that the government should continue to provide incentives even after 20 years. 5. Since the government shares the same goals as TSC, there should be sufficient cooperation and communication that support the technical instruction and reduction of afforestation cost, which will also help to improve effectiveness of the policy.
Abstract: In this paper, we propose a dynamic TDMA slot
reservation (DTSR) protocol for cognitive radio ad hoc networks.
Quality of Service (QoS) guarantee plays a critically important role
in such networks. We consider the problem of providing QoS
guarantee to users as well as to maintain the most efficient use of
scarce bandwidth resources. According to one hop neighboring
information and the bandwidth requirement, our proposed protocol
dynamically changes the frame length and the transmission schedule.
A dynamic frame length expansion and shrinking scheme that
controls the excessive increase of unassigned slots has been
proposed. This method efficiently utilizes the channel bandwidth by
assigning unused slots to new neighboring nodes and increasing the
frame length when the number of slots in the frame is insufficient to
support the neighboring nodes. It also shrinks the frame length when
half of the slots in the frame of a node are empty. An efficient slot
reservation protocol not only guarantees successful data
transmissions without collisions but also enhance channel spatial
reuse to maximize the system throughput. Our proposed scheme,
which provides both QoS guarantee and efficient resource utilization,
be employed to optimize the channel spatial reuse and maximize the
system throughput. Extensive simulation results show that the
proposed mechanism achieves desirable performance in multichannel
multi-rate cognitive radio ad hoc networks.
Abstract: A direct adaptive controller for a class of unknown nonlinear discrete-time systems is presented in this article. The proposed controller is constructed by fuzzy rules emulated network (FREN). With its simple structure, the human knowledge about the plant is transferred to be if-then rules for setting the network. These adjustable parameters inside FREN are tuned by the learning mechanism with time varying step size or learning rate. The variation of learning rate is introduced by main theorem to improve the system performance and stabilization. Furthermore, the boundary of adjustable parameters is guaranteed through the on-line learning and membership functions properties. The validation of the theoretical findings is represented by some illustrated examples.
Abstract: This work presents a new approach of securing a
wireless network. The configuration is focused on securing &
Protecting wireless network traffic for a small network such as a
home or dorm room. The security Mechanism provided both
authentication, allowing only known authorized users access to the
wireless network, and encryption, preventing anyone from reading
the wireless traffic. The mentioned solution utilizes the open source
free S/WAN software which implements the Internet Protocol
Security –IPSEC. In addition to wireless components, wireless NIC
in PC and wireless access point needs a machine running Linux to act
as security gateway. While the current configuration assumes that the
wireless PC clients are running Linux, Windows XP/VISTA/7 based
machines equipped with VPN software which will allow to interface
with this configuration.
Abstract: The proliferation of web application and the pervasiveness of mobile technology make web-based attacks even more attractive and even easier to launch. Web Application Firewall (WAF) is an intermediate tool between web server and users that provides comprehensive protection for web application. WAF is a negative security model where the detection and prevention mechanisms are based on predefined or user-defined attack signatures and patterns. However, WAF alone is not adequate to offer best defensive system against web vulnerabilities that are increasing in number and complexity daily. This paper presents a methodology to automatically design a positive security based model which identifies and allows only legitimate web queries. The paper shows a true positive rate of more than 90% can be achieved.
Abstract: The angular distribution of Compton scattering of two
quanta originating in the annihilation of a positron with an electron
is investigated as a quantum key distribution (QKD) mechanism in
the gamma spectral range. The geometry of coincident Compton
scattering is observed on the two sides as a way to obtain partially
correlated readings on the quantum channel. We derive the noise
probability density function of a conceptually equivalent prepare
and measure quantum channel in order to evaluate the limits of the
concept in terms of the device secrecy capacity and estimate it at
roughly 1.9 bits per 1 000 annihilation events. The high error rate
is well above the tolerable error rates of the common reconciliation
protocols; therefore, the proposed key agreement protocol by public
discussion requires key reconciliation using classical error-correcting
codes. We constructed a prototype device based on the readily
available monolithic detectors in the least complex setup.
Abstract: IEEE 802.16 is a new wireless technology standard, it
has some advantages, including wider coverage, higher bandwidth,
and QoS support. As the new wireless technology for last mile
solution, there are designed two models in IEEE 802.16 standard. One
is PMP (point to multipoint) and the other is Mesh. In this paper we
only focus on IEEE 802.16 Mesh model. According to the IEEE
802.16 standard description, Mesh model has two scheduling modes,
centralized and distributed. Considering the pros and cons of the two
scheduling, we present the combined scheduling QoS framework that
the BS (Base Station) controls time frame scheduling and selects the
shortest path from source to destination directly. On the other hand, we
propose the Expedited Queue mechanism to cut down the transmission
time. The EQ mechanism can reduce a lot of end-to-end delay in our
QoS framework. Simulation study has shown that the average delay is
smaller than contrasts. Furthermore, our proposed scheme can also
achieve higher performance.
Abstract: This paper presents PSS (Power system stabilizer) design based on optimal fuzzy PID (OFPID). OFPID based PSS design is considered for single-machine power systems. The main motivation for this design is to stabilize or to control low-frequency oscillation on power systems. Firstly, describing the linear PID control then to combine this PID control with fuzzy logic control mechanism. Finally, Fuzzy PID parameters (Kp. Kd, KI, Kupd, Kui) are tuned by Genetic Algorthm (GA) to reach optimal global stability. The effectiveness of the proposed PSS in increasing the damping of system electromechanical oscillation is demonstrated in a one-machine-infinite-bus system
Abstract: The separation efficiency of a hydrocyclone has
extensively been considered on the rigid particle assumption. A
collection of experimental studies have demonstrated their
discrepancies from the modeling and simulation results. These
discrepancies caused by the actual particle elasticity have generally
led to a larger amount of energy consumption in the separation
process. In this paper, the influence of particle elasticity on the
separation efficiency of a hydrocyclone system was investigated
through the Finite Element (FE) simulations using crude oil droplets
as the elastic particles. A Reitema-s design hydrocyclone with a
diameter of 8 mm was employed to investigate the separation
mechanism of the crude oil droplets from water. The cut-size
diameter eter of the crude oil was 10 - Ðçm in order to fit with the
operating range of the adopted hydrocylone model. Typical
parameters influencing the performance of hydrocyclone were varied
with the feed pressure in the range of 0.3 - 0.6 MPa and feed
concentration between 0.05 – 0.1 w%. In the simulation, the Finite
Element scheme was applied to investigate the particle-flow
interaction occurred in the crude oil system during the process. The
interaction of a single oil droplet at the size of 10 - Ðçm to the flow
field was observed. The feed concentration fell in the dilute flow
regime so the particle-particle interaction was ignored in the study.
The results exhibited the higher power requirement for the separation
of the elastic particulate system when compared with the rigid
particulate system.
Abstract: The presence of chemical bonding between functionalized carbon nanotubes and matrix in carbon nanotube reinforced composites is modeled by elastic beam elements representing covalent bonding characteristics. Neglecting other reinforcing mechanisms in the composite such as relatively weak interatomic Van der Waals forces, this model shows close results to the Rule of Mixtures model-s prediction for effective Young-s modulus of a Representative Volume Element of composite for small volume fractions (~1%) and high aspect ratios (L/D>200) of CNTs.
Abstract: This paper aims at numerically analysing the effect
of an active flow control (AFC) by a vortex generator jet (VGJ)
submerged in a boundary layer via Chimera Grids and Detached-
Eddy Simulation (DES). The performance of DES results are
judged against Reynolds-Averaged Navier-Stokes (RANS) and
compared with the experiments that showed an unsteady vortex
motion downstream of VGJ. Experimental results showed that
the mechanism of embedding logitudinal vortex structure in the
main stream flow is quite effective in increasing the near wall
momentum of separated aircraft wing. In order to simulate such
a flow configuration together with the VGJ, an efficient numerical
approach is required. This requirement is fulfilled by performing
the DES simulation over the flat plate using the DLR TAU Code.
The DES predictions identify the vortex region via smooth hybrid
length scale and predict the unsteady vortex motion observed in
the experiments. The DES results also showed that the sufficient
grid refinement in the vortex region resolves the turbulent scales
downstream of the VGJ, the spatial vortex core postion and nondimensional
momentum coefficient RVx .
Abstract: The motion planning technique described in this paper has been developed to eliminate or reduce the residual vibrations of belt-driven rotary platforms, while maintaining unchanged the motion time and the total angular displacement of the platform. The proposed approach is based on a suitable choice of the motion command given to the servomotor that drives the mechanical device; this command is defined by some numerical coefficients which determine the shape of the displacement, velocity and acceleration profiles. Using a numerical optimization technique, these coefficients can be changed without altering the continuity conditions imposed on the displacement and its time derivatives at the initial and final time instants. The proposed technique can be easily and quickly implemented on an actual device, since it requires only a simple modification of the motion command profile mapped in the memory of the electronic motion controller.
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: We introduce an extended resource leveling model that abstracts real life projects that consider specific work ranges for each resource. Contrary to traditional resource leveling problems this model considers scarce resources and multiple objectives: the minimization of the project makespan and the leveling of each resource usage over time. We formulate this model as a multiobjective optimization problem and we propose a multiobjective genetic algorithm-based solver to optimize it. This solver consists in a two-stage process: a main stage where we obtain non-dominated solutions for all the objectives, and a postprocessing stage where we seek to specifically improve the resource leveling of these solutions. We propose an intelligent encoding for the solver that allows including domain specific knowledge in the solving mechanism. The chosen encoding proves to be effective to solve leveling problems with scarce resources and multiple objectives. The outcome of the proposed solvers represent optimized trade-offs (alternatives) that can be later evaluated by a decision maker, this multi-solution approach represents an advantage over the traditional single solution approach. We compare the proposed solver with state-of-art resource leveling methods and we report competitive and performing results.
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.