Abstract: There are a many of needs for the development of
SiC-based hydrogen sensor for harsh environment applications. We
fabricated and investigated Pd/Ta2O5/SiC-based hydrogen sensors
with MOS capacitor structure for high temperature process monitoring
and leak detection applications in such automotive, chemical and
petroleum industries as well as direct monitoring of combustion
processes. In this work, we used silicon carbide (SiC) as a substrate to
replace silicon which operating temperatures are limited to below
200°C. Tantalum oxide was investigated as dielectric layer which has
high permeability for hydrogen gas and high dielectric permittivity,
compared with silicon dioxide or silicon nitride. Then, electrical
response properties, such as I-V curve and dependence of capacitance
on hydrogen concentrations were analyzed in the temperature ranges
of room temperature to 500°C for performance evaluation of the
sensor.
Abstract: A slant weighted Toeplitz operator Aφ is an operator
on L2(β) defined as Aφ = WMφ where Mφ is the weighted
multiplication operator and W is an operator on L2(β) given by
We2n = βn
β2n
en, {en}n∈Z being the orthonormal basis. In this paper,
we generalise Aφ to the k-th order slant weighted Toeplitz operator
Uφ and study its properties.
Abstract: Many real-world optimization problems involve multiple conflicting objectives and the use of evolutionary algorithms to solve the problems has attracted much attention recently. This paper investigates the application of multi-objective optimization technique for the design of a Thyristor Controlled Series Compensator (TCSC)-based controller to enhance the performance of a power system. The design objective is to improve both rotor angle stability and system voltage profile. A Genetic Algorithm (GA) based solution technique is applied to generate a Pareto set of global optimal solutions to the given multi-objective optimisation problem. Further, a fuzzy-based membership value assignment method is employed to choose the best compromise solution from the obtained Pareto solution set. Simulation results are presented to show the effectiveness and robustness of the proposed approach.
Abstract: The main objective of the paper has been represented
by the identification of the changes that occurred in the competitive
environment and their impact on the strategic marketing management
of companies in B2B market. At Romania-s level there has not yet
been done a similar research that studies change management in
crises on business to business field. In order to answer to the paper-s
objectives, a qualitative marketing research (in-depth structured
interview) was conducted, within the top management of 27
companies in Romanian business to business field. The main results
of the research highlight the necessity of a management of change, as
a result of the crises, as follows: changes in the corporate objectives
(from development objectives to maintaining objectives), changes
market segmentation and in competitive advantages, changes at the
level of market strategies and of the marketing mix.
Abstract: Modern times call organizations to have an active role
in the social arena, through Corporate Social Responsibility (CSR).
The objective of this research was to test the hypothesis that there is a
positive relation between social performance and economic
performance, and if there is a positive correlation between social
performance and financial-economic performance. To test these
theories a measure of social performance, based on the Green Book
of Commission of the European Community, was used in a group of
nineteen Portuguese top companies, listed on the PSI 20 index,
through a period of five years, since 2005 to 2009. A clusters
analysis was applied to group companies by their social performance
and to compare and correlate their economic performance. Results
indicate that companies that had a better social performance are not
the ones who had a better economic performance, and suggest that
the middle path might provide a good relation CSR-Economic
performance, as a basis to a sustainable development.
Abstract: This paper presents an innovative approach within the area of Group Decision Support System (GDSS) by using tools based on intelligent agents. It introduces iGDSS, a software platform for decision support and collaboration and an application of this platform - eCollaborative Decisions - for academic environment, all these developed within a framework of a research project.
Abstract: Enzymatic saccharification of biomass for reducing
sugar production is one of the crucial processes in biofuel production
through biochemical conversion. In this study, enzymatic
saccharification of dilute potassium hydroxide (KOH) pre-treated
Tetraselmis suecica biomass was carried out by using cellulase
enzyme obtained from Trichoderma longibrachiatum. Initially, the
pre-treatment conditions were optimised by changing alkali reagent
concentration, retention time for reaction, and temperature. The T.
suecica biomass after pre-treatment was also characterized using
Fourier Transform Infrared Spectra and Scanning Electron
Microscope. These analyses revealed that the functional group such
as acetyl and hydroxyl groups, structure and surface of T. suecica
biomass were changed through pre-treatment, which is favourable for
enzymatic saccharification process. Comparison of enzymatic
saccharification of untreated and pre-treated microalgal biomass
indicated that higher level of reducing sugar can be obtained from
pre-treated T. suecica. Enzymatic saccharification of pre-treated T.
suecica biomass was optimised by changing temperature, pH, and
enzyme concentration to solid ratio ([E]/[S]). Highest conversion of
carbohydrate into reducing sugar of 95% amounted to reducing sugar
yield of 20 (wt%) from pre-treated T. suecica was obtained from
saccharification, at temperature: 40°C, pH: 4.5 and [E]/[S] of 0.1
after 72 h of incubation. Hydrolysate obtained from enzymatic
saccharification of pretreated T. suecica biomass was further
fermented into biobutanol using Clostridium saccharoperbutyliticum
as biocatalyst. The results from this study demonstrate a positive
prospect of application of dilute alkaline pre-treatment to enhance
enzymatic saccharification and biobutanol production from
microalgal biomass.
Abstract: Due to insufficient frequency band and tremendous growth of the mobile users, complex computation is needed for the use of resources. Long distance communication began with the introduction of telegraphs and simple coded pulses, which were used to transmit short messages. Since then numerous advances have rendered reliable transfer of information both easier and quicker. Wireless network refers to any type of computer network that is wireless, and is commonly associated with a telecommunications network whose interconnections between nodes is implemented without the use of wires. Wireless network can be broadly categorized in infrastructure network and infrastructure less network. Infrastructure network is one in which we have a base station to serve the mobile users and in the infrastructure less network is one in which no infrastructure is available to serve the mobile users this kind of networks are also known as mobile Adhoc networks. In this paper we have simulated the result for different scenarios with protocols like AODV and DSR; we simulated the result for throughput, delay and receiving traffic in the given scenario.
Abstract: The hydrodynamic and thermal lattice Boltzmann
methods are applied to investigate the turbulent convective heat
transfer in the wavy channel flows. In this study, the turbulent
phenomena are modeling by large-eddy simulations with the
Smagorinsky model. As a benchmark, the laminar and turbulent
backward-facing step flows are simulated first. The results give good
agreement with other numerical and experimental data. For wavy
channel flows, the distribution of Nusselt number and the skin-friction
coefficients are calculated to evaluate the heat transfer effect and the
drag force. It indicates that the vortices at the trough would affect the
magnitude of drag and weaken the heat convection effects on the wavy
surface. In turbulent cases, if the amplitude of the wavy boundary is
large enough, the secondary vortices would be generated at troughs
and contribute to the heat convection. Finally, the effects of different
Re on the turbulent transport phenomena are discussed.
Abstract: In this paper, we consider Wiener nonlinear model for solid oxide fuel cell (SOFC). The Wiener model of the SOFC consists of a linear dynamic block and a static output non-linearity followed by the block, in which linear part is approximated by state-space model and the nonlinear part is identified by a polynomial form. To control the SOFC system, we have to consider various view points such as operating conditions, another constraint conditions, change of load current and so on. A change of load current is the significant one of these for good performance of the SOFC system. In order to keep the constant stack terminal voltage by changing load current, the nonlinear model predictive control (MPC) is proposed in this paper. After primary control method is designed to guarantee the fuel utilization as a proper constant, a nonlinear model predictive control based on the Wiener model is developed to control the stack terminal voltage of the SOFC system. Simulation results verify the possibility of the proposed Wiener model and MPC method to control of SOFC system.
Abstract: A CFD software was employed to analyze the
characteristics of the flat round porous aerostatic bearings. The effects
of gap between the bearing and the guide way and the porosity of the
porous material on the load capacity of the bearing were studied. The
adequacy of the simulation model and the approach was verified. From
the parametric study, it is found that the depth of the flow path does not
influence the load capacity of the bearing; the load capacity of the
bearing will decrease if the thickness of the porous material increases
or the porous material protrudes above the bearing housing; the
variation of the chamfer at the edge of the bearing does not affect the
bearing load capacity. For a bearing with an air gap of 5μm and a
porosity of 0.1, the average load capacity and the pressure distribution
of the bearing are nearly unchanged no matter the bearing moves at a
constant or a varying speed.
Abstract: Characterized as rich mineral substances, low
temperature, few bacteria, and stability with numerous implementation
aspects on aquaculture, food, drinking, and leisure, the deep sea water
(DSW) development has become a new industry in the world. It has
been report that marine algae contain various biologically active
compounds. This research focued on the affections in cultivating
Sagrassum cristaefolium with different concentration of deep sea
water(DSW) and surface sea water(SSW). After two and four weeks,
the total phenolic contents were compared in Sagrassum cristaefolium
culturing with different ways, and the reductive activity of them was
also be tried with potassium ferricyanide. Those fresh seaweeds were
dried with oven and were ground to powder. Progressively, the marine
algae we cultured was extracted by water under the condition with
heating them at 90Ôäâ for 1hr.The total phenolic contents were be
executed using Folin–Ciocalteu method. The results were explaining
as follows: the highest total phenolic contents and the best reductive
ability of all could be observed on the 1/4 proportion of DSW to SSW
culturing in two weeks. Furthermore, the 1/2 proportion of DSW to
SSW also showed good reductive ability and plentiful phenolic
compositions. Finally, we confirmed that difference proportion of
DSW and SSW is the major point relating to ether the total phenolic
components or the reductive ability in the Sagrassum cristaefolium. In
the future, we will use this way to mass production the marine algae or
other micro algae on industry applications.