Abstract: The research focuses on the effects of polyphenols
extracted from Sambucus nigra fruit, using an experimental arterial
hypertension pattern, as well as their influence on the oxidative
stress. The results reveal the normalization of the reduced glutathion
concentration, as well as a considerable reduction in the
malondialdehide serum concentration by the polyphenolic protection.
The rat blood pressure values were recorded using a CODATM
system, which uses a non-invasive blood pressure measuring method.
All the measured blood pressure components revealed a biostatistically
significant (p
Abstract: Operational risk has become one of the most discussed topics in the financial industry in the recent years. The reasons for this attention can be attributed to higher investments in information systems and technology, the increasing wave of mergers and acquisitions and emergence of new financial instruments. In addition, the New Basel Capital Accord (known as Basel II) demands a capital requirement for operational risk and further motivates financial institutions to more precisely measure and manage this type of risk. The aim of this paper is to shed light on main characteristics of operational risk management and common applied methods: scenario analysis, key risk indicators, risk control self assessment and loss distribution approach.
Abstract: In reality, the process observations are away from the assumption that are normal distributed. The observations could be skew distributions which should use an asymmetric chart rather than symmetric chart. Consequently, this research aim to study the robustness of the asymmetric Tukey’s control chart for skew and non-skew distributions as Lognormal and Laplace distributions. Furthermore, the performances in detecting of a change in parameter of asymmetric and symmetric Tukey’s control charts are compared by Average ARL (AARL). The results found that the asymmetric performs better than symmetric Tukey’s control chart for both cases of skew and non-skew process observation.
Abstract: The work reported in this paper proposes
Swarm-Array computing, a novel technique inspired by swarm
robotics, and built on the foundations of autonomic and parallel
computing. The approach aims to apply autonomic computing
constructs to parallel computing systems and in effect achieve the
self-ware objectives that describe self-managing systems. The
constitution of swarm-array computing comprising four constituents,
namely the computing system, the problem/task, the swarm and the
landscape is considered. Approaches that bind these constituents
together are proposed. Space applications employing FPGAs are
identified as a potential area for applying swarm-array computing for
building reliable systems. The feasibility of a proposed approach is
validated on the SeSAm multi-agent simulator and landscapes are
generated using the MATLAB toolkit.
Abstract: The design of methods of the 20 K large dimension cold shield used for infrared radiation demarcating in space environment simulation test were introduced in this paper. The cold shield were cooled by five G-M cryocoolers , and the dimension of the cold shield is the largest in our country.Cold shield installation and distribution and compensator for contraction on cooling were introduced detailedly. The temperature distribution and cool-down time of cold shield surface were also calculated and analysed in this paper. The design of cold shield resolves the difficulty of compensator for contraction on cooling successfully. Test results show that the actual technical performance indicators of cold shield met and exceeded the design requirements.
Abstract: The paper presents an applied study of a multivariate AR(p) process fitted to daily data from U.S. commodity futures markets with the use of Bayesian statistics. In the first part a detailed description of the methods used is given. In the second part two BVAR models are chosen one with assumption of lognormal, the second with normal distribution of prices conditioned on the parameters. For a comparison two simple benchmark models are chosen that are commonly used in todays Financial Mathematics. The article compares the quality of predictions of all the models, tries to find an adequate rate of forgetting of information and questions the validity of Efficient Market Hypothesis in the semi-strong form.
Abstract: In this study, a robust intelligent backstepping tracking control (RIBTC) system combined with adaptive output recurrent cerebellar model articulation control (AORCMAC) and H∞ control technique is proposed for wheeled inverted pendulums (WIPs) real-time control with exact system dynamics unknown. Moreover, a robust H∞ controller is designed to attenuate the effect of the residual approximation errors and external disturbances with desired attenuation level. The experimental results indicate that the WIPs can stand upright stably when using the proposed RIBTC.
Abstract: The Zung self-depression scale and Beck Anxiety Inventory were used to study the depression and anxiety levels of Armenian Crohn's disease patients, as well as to reveal the relation between emotional status and placebo effect of these patients. Despite of registered high levels of depression and anxiety, the high placebo rate during investigations was described. The importance of use of psychotherapies for optimal outcomes during treatments of Crohn's disease is obvious.
Abstract: In this study, the two dimensional heat conduction
problem for the dry friction clutch disc is modeled mathematically
analysis and is solved numerically using finite element method, to
determine the temperature field when band contacts occurs between
the rubbing surfaces during the operation of an automotive clutch.
Temperature calculation have been made for contact area of different
band width and the results obtained compared with these attained
when complete contact occurs. Furthermore, the effects of slipping
time and sliding velocity function are investigated as well. Both
single and repeated engagements made at regular interval are
considered.
Abstract: This paper attempts to identify the significance of
Information and Communications Technology (ICT) and
competitiveness to the profit efficiency of commercial banks in
Malaysia. The profit efficiency of commercial banks in Malaysia, the
dependent variable, was estimated using the Stochastic Frontier
Approach (SFA) on a sample of unbalanced panel data, covering 23
commercial banks, between 1995 to 2007. Based on the empirical
results, ICT was not found to exert a significant impact on profit
efficiency, whereas competitiveness, non ICT stock expenditure and
ownership were significant contributors. On the other hand, the size
of banks was found to have significantly reduced profit efficiency,
opening up for various interpretations of the interrelated role of ICT
and competition.
Abstract: Whilst there is growing evidence that activity across the lifespan is beneficial for improved health, there are also many changes involved with the aging process and subsequently the potential for reduced indices of health. Data gathered on a subsample of 535 football code athletes, aged 31-72 yrs ( = 47.4, s = ±7.1), competing at the Sydney World Masters Games (2009) demonstrated a significantly (p < 0.001), reduced classification of obesity using Body Mass Index (BMI) when compared to the general Australian population. This evidence of improved classification in one index of health (BMI < 30) for master athletes (when compared to the general population) implies there are either improved levels of this index of health due to adherence to sport or possibly the reduced BMI is advantageous and contributes to this cohort adhering (or being attracted) to masters sport. Demonstration of this proportionately under-investigated World Masters Games population having improved health over the general population is of particular interest.
Abstract: A new class of percolation model in complex networks,
in which nodes are characterized by hidden variables reflecting the
properties of nodes and the occupied probability of each link is
determined by the hidden variables of the end nodes, is studied
in this paper. By the mean field theory, the analytical expressions
for the phase of percolation transition is deduced. It is determined
by the distribution of the hidden variables for the nodes and the
occupied probability between pairs of them. Moreover, the analytical
expressions obtained are checked by means of numerical simulations
on a particular model. Besides, the general model can be applied
to describe and control practical diffusion models, such as disease
diffusion model, scientists cooperation networks, and so on.
Abstract: This paper studies, maps and explains the interactions between downloaders and uploaders pertaining to the Internet film piracy. This study also covers several motivational factors that influence users to upload or download movies, and thus to engage in film piracy over the Internet. The essay also proposes a model that describes user behavior including their relationships and influences. Moreover, proposed theoretical interactions and motivational factors are applied to the real world scenario, using examples of a data storage webpage server Ulozto.net and webpage Piratebay.org gathering information about downloadable BitTorrents. Moreover, the theory is further supported by description of behavior of real Internet uploaders.
Abstract: Hierarchical Mobile IPv6 (HMIPv6) was designed to
support IP micro-mobility management in the Next Generation
Networks (NGN) framework. The main design behind this protocol is
the usage of Mobility Anchor Point (MAP) located at any level router
of network to support hierarchical mobility management. However,
the distance MAP selection in HMIPv6 causes MAP overloaded and
increase frequent binding update as the network grows. Therefore, to
address the issue in designing MAP selection scheme, we propose a
dynamic load control mechanism integrates with a speed detection
mechanism (DMS-DLC). From the experimental results we obtain
that the proposed scheme gives better distribution in MAP load and
increase handover speed.
Abstract: A portable sensor for the analysis of phosphate in
aqueous samples has been developed. The sensor incorporates
microfluidic technology, colorimetric detection, and wireless
communications into a compact and rugged portable device. The
detection method used is the molybdenum yellow method, in which a
phosphate-containing sample is mixed with a reagent containing
ammonium metavanadate and ammonium molybdate in an acidic
medium. A yellow-coloured compound is generated and the
absorption of this compound is measured using a light emitting diode
(LED) light source and a photodiode detector. The absorption is
directly proportional to the phosphate concentration in the original
sample. In this paper we describe the application of this phosphate
sensor to the analysis of wastewater at a municipal wastewater
treatment plant in Co. Kildare, Ireland.
Abstract: This paper presents the influence of preloading on a)
the contact tractions, b) slip levels and c) stresses at the dovetail
blade-disc interface of an aero-engine through a three-dimensional
(3D) finite element (FE) modeling and analysis. The preloading is
applied by an interference fit at the dovetail interface and the bulk
loading is applied through the rotational speed of rotor. Preloading at
the dovetail interface reduces the peak contact pressure developed
due to bulk loading up to 35%, and reduces the peak contact pressure
and stress difference between top and bottom contact edges.
Increasing the level of preloading reduces the cyclic stress amplitude
at the interface up to certain values of preload and as a consequence,
an improvement in fatigue life could be expected. Fretting damage,
due to vibration and wind milling effect during engine ground
condition, can be minimized by preloading the dovetail interface.
Abstract: In this study, the sorption of Malachite green (MG) on Hydrilla verticillata biomass, a submerged aquatic plant, was investigated in a batch system. The effects of operating parameters such as temperature, adsorbent dosage, contact time, adsorbent size, and agitation speed on the sorption of Malachite green were analyzed using response surface methodology (RSM). The proposed quadratic model for central composite design (CCD) fitted very well to the experimental data that it could be used to navigate the design space according to ANOVA results. The optimum sorption conditions were determined as temperature - 43.5oC, adsorbent dosage - 0.26g, contact time - 200min, adsorbent size - 0.205mm (65mesh), and agitation speed - 230rpm. The Langmuir and Freundlich isotherm models were applied to the equilibrium data. The maximum monolayer coverage capacity of Hydrilla verticillata biomass for MG was found to be 91.97 mg/g at an initial pH 8.0 indicating that the optimum sorption initial pH. The external and intra particle diffusion models were also applied to sorption data of Hydrilla verticillata biomass with MG, and it was found that both the external diffusion as well as intra particle diffusion contributes to the actual sorption process. The pseudo-second order kinetic model described the MG sorption process with a good fitting.
Abstract: Snow cover is an important phenomenon in
hydrology, hence modeling the snow accumulation and melting is an
important issue in places where snowmelt significantly contributes to
runoff and has significant effect on water balance. The physics-based
models are invariably distributed, with the basin disaggregated into
zones or grid cells. Satellites images provide valuable data to verify
the accuracy of spatially distributed model outputs. In this study a
spatially distributed physically based model (WetSpa) was applied to
predict snow cover and melting in the Latyan dam watershed in Iran.
Snowmelt is simulated based on an energy balance approach. The
model is applied and calibrated with one year of observed daily
precipitation, air temperature, windspeed, and daily potential
evaporation. The predicted snow-covered area is compared with
remotely sensed images (MODIS). The results show that simulated
snow cover area SCA has a good agreement with satellite image
snow cover area SCA from MODIS images. The model performance
is also tested by statistical and graphical comparison of simulated and
measured discharges entering the Latyan dam reservoir.
Abstract: This paper describes an experimental, theoretical
model and numerical study of concentrated vortex flow past a sphere
in a hydraulic check valve. The phenomenon of the rotation of the
ball around the axis of the device through which liquid flows has
been found. That is, due to the rotation of the sphere in the check
valve vibration is caused. We observe the rotation of the sphere
around the longitudinal axis of the check valve. This rotation is
induced by a vortex shedding from the sphere. We will discuss
computational simulation and experimental investigations of this
strong sphere rotation. The frequency of the sphere vibration and
interaction with the check valve wall has been measured as a function
of the wide range Reynolds Number. The validity of the
computational simulation and of the assumptions on which it is based
has been proved experimentally. This study demonstrates the
possibility to control the vibrations in a hydraulic system and proves
to be very effective suppression of the self-excited vibration.
Abstract: Helical milling operations are used to generate or
enlarge boreholes by means of a milling tool. The bore diameter can be
adjusted through the diameter of the helical path. The kinematics of
helical milling on a three axis machine tool is analysed firstly. The
relationships between processing parameters, cutting tool geometry
characters with machined hole feature are formulated. The feed motion
of the cutting tool has been decomposed to plane circular feed and
axial linear motion. In this paper, the time varying cutting forces acted
on the side cutting edges and end cutting edges of the flat end cylinder
miller is analysed using a discrete method separately. These two
components then are combined to produce the cutting force model
considering the complicated interaction between the cutters and
workpiece. The time varying cutting force model describes the
instantaneous cutting force during processing. This model could be
used to predict cutting force, calculate statics deflection of cutter and
workpiece, and also could be the foundation of dynamics model and
predicting chatter limitation of the helical milling operations.