Abstract: We analyze the effectivity of different pseudo noise (PN) and orthogonal sequences for encrypting speech signals in terms of perceptual intelligence. Speech signal can be viewed as sequence of correlated samples and each sample as sequence of bits. The residual intelligibility of the speech signal can be reduced by removing the correlation among the speech samples. PN sequences have random like properties that help in reducing the correlation among speech samples. The mean square aperiodic auto-correlation (MSAAC) and the mean square aperiodic cross-correlation (MSACC) measures are used to test the randomness of the PN sequences. Results of the investigation show the effectivity of large Kasami sequences for this purpose among many PN sequences.
Abstract: Continuously growing needs for Internet applications
that transmit massive amount of data have led to the emergence of
high speed network. Data transfer must take place without any
congestion and hence feedback parameters must be transferred from
the receiver end to the sender end so as to restrict the sending rate in
order to avoid congestion. Even though TCP tries to avoid
congestion by restricting the sending rate and window size, it never
announces the sender about the capacity of the data to be sent and
also it reduces the window size by half at the time of congestion
therefore resulting in the decrease of throughput, low utilization of
the bandwidth and maximum delay. In this paper, XCP protocol is
used and feedback parameters are calculated based on arrival rate,
service rate, traffic rate and queue size and hence the receiver
informs the sender about the throughput, capacity of the data to be
sent and window size adjustment, resulting in no drastic decrease in
window size, better increase in sending rate because of which there is
a continuous flow of data without congestion. Therefore as a result of
this, there is a maximum increase in throughput, high utilization of
the bandwidth and minimum delay. The result of the proposed work
is presented as a graph based on throughput, delay and window size.
Thus in this paper, XCP protocol is well illustrated and the various
parameters are thoroughly analyzed and adequately presented.
Abstract: A device analysis of the photoconductive
semiconductor switch is carried out to investigate distribution of
electric field and carrier concentrations as well as the current density
distribution. The operation of this device was then investigated as a
switch operating in X band. It is shown that despite the presence of
symmetry geometry, switch current density of the on-state steady
state mode is distributed asymmetrically throughout the device.
Abstract: This paper argues that increased uncertainty, in certain
situations, may actually encourage investment. Since earlier studies
mostly base their arguments on the assumption of geometric Brownian
motion, the study extends the assumption to alternative stochastic
processes, such as mixed diffusion-jump, mean-reverting process, and
jump amplitude process. A general approach of Monte Carlo
simulation is developed to derive optimal investment trigger for the
situation that the closed-form solution could not be readily obtained
under the assumption of alternative process. The main finding is that
the overall effect of uncertainty on investment is interpreted by the
probability of investing, and the relationship appears to be an invested
U-shaped curve between uncertainty and investment. The implication
is that uncertainty does not always discourage investment even under
several sources of uncertainty. Furthermore, high-risk projects are not
always dominated by low-risk projects because the high-risk projects
may have a positive realization effect on encouraging investment.
Abstract: This paper presents an architecture of current filesystem
implementations as well as our new filesystem SpadFS and operating
system Spad with rewritten VFS layer targeted at high performance
I/O applications. The paper presents microbenchmarks and real-world
benchmarks of different filesystems on the same kernel as well as
benchmarks of the same filesystem on different kernels – enabling
the reader to make conclusion how much is the performance of
various tasks affected by operating system and how much by physical
layout of data on disk. The paper describes our novel features–most
notably continuous allocation of directories and cross-file readahead
– and shows their impact on performance.
Abstract: Data hiding into text documents itself involves pretty
complexities due to the nature of text documents. A robust text
watermarking scheme targeting an object based environment is
presented in this research. The heart of the proposed solution
describes the concept of watermarking an object based text document
where each and every text string is entertained as a separate object
having its own set of properties. Taking advantage of the z-ordering
of objects watermark is applied with the z-axis letting zero fidelity
disturbances to the text. Watermark sequence of bits generated
against user key is hashed with selected properties of given
document, to determine the bit sequence to embed. Bits are
embedded along z-axis and the document has no fidelity issues when
printed, scanned or photocopied.
Abstract: The alterations in pancreas gland secretion hormones
following an aerobic and exhausting exercise was the purpose of this
study. Sixteen healthy men participated in the study. The blood
samples of these participants were taken in four stages under fasting
condition. The first sample was taken before Bruce exhausting and
aerobic test, the second sample was taken after Bruce exercise and
the third and forth stages samples were taken 24 and 48 hours after
the exercises respectively. The final results indicated that a strenuous
aerobic exercise can have a significant effect on glucagon and insulin
concentration of blood serum. The increase in blood serum insulin
was higher after 24 and 48 hours. It seems that an intensive exercise
has little effect on changes in glucagon concentration of blood serum.
Also, disorder in secretion in glucagon and insulin concentration of
serum disturbs athletes- exercise.
Abstract: This paper proposes a VPN Accelerator Board
(VPN-AB), a virtual private network (VPN) protocol designed for
trust channel security system (TCSS). TCSS supports safety
communication channel between security nodes in internet. It
furnishes authentication, confidentiality, integrity, and access control
to security node to transmit data packets with IPsec protocol. TCSS
consists of internet key exchange block, security association block,
and IPsec engine block. The internet key exchange block negotiates
crypto algorithm and key used in IPsec engine block. Security
Association blocks setting-up and manages security association
information. IPsec engine block treats IPsec packets and consists of
networking functions for communication. The IPsec engine block
should be embodied by H/W and in-line mode transaction for high
speed IPsec processing. Our VPN-AB is implemented with high speed
security processor that supports many cryptographic algorithms and
in-line mode. We evaluate a small TCSS communication environment,
and measure a performance of VPN-AB in the environment. The
experiment results show that VPN-AB gets a performance throughput
of maximum 15.645Gbps when we set the IPsec protocol with
3DES-HMAC-MD5 tunnel mode.
Abstract: This work is focused on the numerical prediction of the fracture resistance of a flat stiffened panel made of the aluminium alloy 2024 T3 under a monotonic traction condition. The performed numerical simulations have been based on the micromechanical Gurson-Tvergaard (GT) model for ductile damage. The applicability of the GT model to this kind of structural problems has been studied and assessed by comparing numerical results, obtained by using the WARP 3D finite element code, with experimental data available in literature. In the sequel a home-made procedure is presented, which aims to increase the residual strength of a cracked stiffened aluminum panel and which is based on the stochastic design improvement (SDI) technique; a whole application example is then given to illustrate the said technique.
Abstract: Inventory decisional environment of short life-cycle
products is full of uncertainties arising from randomness and
fuzziness of input parameters like customer demand requiring
modeling under hybrid uncertainty. Prior inventory models
incorporating fuzzy demand have unfortunately ignored stochastic
variation of demand. This paper determines an unambiguous optimal
order quantity from a set of n fuzzy observations in a newsvendor
inventory setting in presence of fuzzy random variable demand
capturing both fuzzy perception and randomness of customer
demand. The stress of this paper is in providing solution procedure
that attains optimality in two steps with demand information
availability in linguistic phrases leading to fuzziness along with
stochastic variation. The first step of solution procedure identifies
and prefers one best fuzzy opinion out of all expert opinions and the
second step determines optimal order quantity from the selected
event that maximizes profit. The model and solution procedure is
illustrated with a numerical example.
Abstract: In this paper, we investigate a class of fuzzy Cohen- Grossberg neural networks with time delays and impulsive effects. By virtue of stochastic analysis, Halanay inequality for stochastic differential equations, we find sufficient conditions for the global exponential square-mean synchronization of the FCGNNs under noise perturbation. In particular, the traditional assumption on the differentiability of the time-varying delays is no longer needed. Finally, a numerical example is given to show the effectiveness of the results in this paper.
Abstract: Extracellular ubiquitin in vivo effect on regenerative liver cells and liver histoarchitectonics has been studied. Experiments were performed on mature female white rats. Partial hepatectomy was made using the modified method of Higgins and Anderson. Standard histopathological assessment of liver tissue was used. Proliferative activity of hepatocytes was analyzed by colchicine mitotic index and immunohistochemical staining on ki67. We have found that regardless of number of injections and dose of extracellular ubiquitin liver histology has not been changed, so at tissue level no effect was observed. In vivo double injection of ubiquitin significantly decreases the mitotic activity at 32 hour point after partial hepatectomy. Thus, we can conclude that in vivo injected extracellular ubiquitin inhibits proliferative activity of hepatocytes in partially hepatectomyzed rats.
Abstract: The client server systems using mobile
communications networks for data transmission became very
attractive for many economic agents, in the purpose of promoting and
offering electronic services to their clients. E-services are suitable for
business developing and financial benefits increasing. The products
or services can be efficiently delivered to a large number of clients,
using mobile Internet access technologies. The clients can have
access to e-services, anywhere and anytime, with the support of 3G,
GPRS, WLAN, etc., channels bandwidth, data services and protocols.
Based on the mobile communications networks evolution and
development, a convergence of technological and financial interests
of mobile operators, software developers, mobile terminals producers
and e-content providers is established. These will lead to a high level
of integration of IT&C resources and will facilitate the value added
services delivery through the mobile communications networks. In
this paper it is presented a client server system, for e-services access,
with Smartphones and PDA-s mobile software applications, installed
on Symbian and Windows Mobile operating systems.
Abstract: This paper proposes a method to vibration analysis in
order to on-line monitoring and predictive maintenance during the
milling process. Adapting envelope method to diagnostics and the
analysis for milling tool materials is an important contribution to the
qualitative and quantitative characterization of milling capacity and a
step by modeling the three-dimensional cutting process. An
experimental protocol was designed and developed for the
acquisition, processing and analyzing three-dimensional signal. The
vibration envelope analysis is proposed to detect the cutting capacity
of the tool with the optimization application of cutting parameters.
The research is focused on Hilbert transform optimization to evaluate
the dynamic behavior of the machine/ tool/workpiece.
Abstract: In the paper, based on stochastic analysis theory and Lyapunov functional method, we discuss the mean square stability of impulsive stochastic delay differential equations with markovian switching and poisson jumps, and the sufficient conditions of mean square stability have been obtained. One example illustrates the main results. Furthermore, some well-known results are improved and generalized in the remarks.
Abstract: In production of medicinal plants, seed germination is
very important problem. The treated seeds (control, hydro priming
and ZnSO4) of Cumin (Cuminum cyminum L.) were evaluated at
germination and seedling growth for tolerance to salt (NaCl and
Na2SO4) conditions at the same water potentials of 0.0, -0.3, -0.6, -
0.9 and -1.2MPa. Electrical conductivity (EC) values of the NaCl
solutions were 0.0, 6.5, 12.7, 18.4 and 23.5 dSm-1, respectively. The
objective of the study was to determine factors responsible for
germination and early seedling growth due to salt toxicity or osmotic
effect and to optimize the best priming treatment for these stress
conditions. Results revealed that germination delayed in both
solutions, having variable germination with different priming
treatments. Germination, shoot and weight, root and shoot length
were higher but mean germination time and abnormal germination
percentage were lower in NaCl than Na2SO4 at the same water
potential. The root / shoot weight and R/S length increased with
increase in osmotic potential in both NaCl and Na2SO4 solutions.
NaCl had less inhibitor effect on seedling growth than the
germination. It was concluded that inhibition of germination at the
same water potential of NaCl and Na2SO4 resulted from salt toxicity
rather than osmotic effect. Hydro priming increased germination and
seedling growth under salt stress. This protocol has practical
importance and could be recommended to farmers to achieve higher
germination and uniform emergence under field conditions.
Abstract: Real-time embedded systems should benefit from
component-based software engineering to handle complexity and
deal with dependability. In these systems, applications should not
only be logically correct but also behave within time windows.
However, in the current component based software engineering
approaches, a few of component models handles time properties in
a manner that allows efficient analysis and checking at the
architectural level. In this paper, we present a meta-model for
component-based software description that integrates timing
issues. To achieve a complete functional model of software
components, our meta-model focuses on four functional aspects:
interface, static behavior, dynamic behavior, and interaction
protocol. With each aspect we have explicitly associated a time
model. Such a time model can be used to check a component-s
design against certain properties and to compute the timing
properties of component assemblies.
Abstract: Wireless Sensor Network is widely used in electronics. Wireless sensor networks are now used in many applications including military, environmental, healthcare applications, home automation and traffic control. We will study one area of wireless sensor networks, which is the routing protocol. Routing protocols are needed to send data between sensor nodes and the base station. In this paper, we will discuss two routing protocols, such as datacentric and hierarchical routing protocol. We will show the output of the protocols using the NS-2 simulator. This paper will compare the simulation output of the two routing protocol using Nam. We will simulate using Xgraph to find the throughput and delay of the protocol.
Abstract: In this paper an efficient incomplete factorization preconditioner is proposed for the Least Mean Squares (LMS) adaptive filter. The proposed preconditioner is approximated from a priori knowledge of the factors of input correlation matrix with an incomplete strategy, motivated by the sparsity patter of the upper triangular factor in the QRD-RLS algorithm. The convergence properties of IPLMS algorithm are comparable with those of transform domain LMS(TDLMS) algorithm. Simulation results show efficiency and robustness of the proposed algorithm with reduced computational complexity.
Abstract: Three new algorithms based on minimization of autocorrelation of transmitted symbols and the SLM approach which are computationally less demanding have been proposed. In the first algorithm, autocorrelation of complex data sequence is minimized to a value of 1 that results in reduction of PAPR. Second algorithm generates multiple random sequences from the sequence generated in the first algorithm with same value of autocorrelation i.e. 1. Out of these, the sequence with minimum PAPR is transmitted. Third algorithm is an extension of the second algorithm and requires minimum side information to be transmitted. Multiple sequences are generated by modifying a fixed number of complex numbers in an OFDM data sequence using only one factor. The multiple sequences represent the same data sequence and the one giving minimum PAPR is transmitted. Simulation results for a 256 subcarrier OFDM system show that significant reduction in PAPR is achieved using the proposed algorithms.