Abstract: In this paper, a delayed predator-prey system with Hassell-Varley-Holling type functional response is studied. A sufficient criterion for the permanence of the system is presented, and further some sufficient conditions for the global attractivity and exponential stability of the system are established. And an example is to show the feasibility of the results by simulation.
Abstract: Aluminum alloy sheets have several advantages such
as the lightweight, high-specific strength and recycling efficiency.
Therefore, aluminum alloy sheets in sheet forming have been used in various areas as automotive components and so forth. During the
process of sheet forming, wrinkling which is caused by compression stress might occur and the formability of sheets was affected by
occurrence of wrinkling. A few studies of uniaxial compressive test by
using square tubes, pipes and sheets were carried out to clarify the each wrinkling behavior. However, on uniaxial compressive test,
deformation behavior of the sheets hasn-t be cleared. Then, it is necessary to clarify the relationship between the buckling behavior
and the forming conditions. In this study, the effect of dimension of the sheet in the buckling behavior on compression test of aluminum alloy sheet was cleared by experiment and FEA. As the results, the buckling
deformation was classified by three modes in terms of the distribution of equivalent plastic strain.
Abstract: This paper examines the readability of the chairman’s narratives, as determined by the Flesch score, of a Malaysian public listed company’s corporate reports from 1962 to 2009. It partially supports earlier studies which demonstrated that corporate reports were difficult to read, and had shown very negligible decrease in difficulty over time. Net profit to sales and readability was significantly positively correlated but number of financial statements was significantly negatively correlated with readability.
Abstract:
Innovation is becoming more and more important in
modern society. There are a lot of researches on different kinds of
innovation but marketing innovation is one kind of innovation that
has not been studied frequently before. Marketing innovation is
defined as a new way in which companies can market themselves to
potential or existing customers.
The study shows some key elements for marketing innovation that
are worth paying attention to when implementing marketing
innovation projects. Examples of such key elements are: paying
attention to the neglected market, suitable market segmentatio
reliable market information, public relationship, increased customer
value, combination of market factors, explore different marketing
channels and the use of technology in combination with what? Beside
the key elements for marketing innovation, we also present some
risks that may occur, such as cost, market uncertainty, information
leakage, imitation and overdependence on experience.
By proposing a set of indicators to measure marketing innovation,
the article offers solutions for marketing innovation implementation
so that any organization can achieve optimal results.
Abstract: In this paper, a method based on Non-Dominated
Sorting Genetic Algorithm (NSGA) has been presented for the Volt /
Var control in power distribution systems with dispersed generation
(DG). Genetic algorithm approach is used due to its broad
applicability, ease of use and high accuracy. The proposed method is
better suited for volt/var control problems. A multi-objective
optimization problem has been formulated for the volt/var control of
the distribution system. The non-dominated sorting genetic algorithm
based method proposed in this paper, alleviates the problem of tuning
the weighting factors required in solving the multi-objective volt/var
control optimization problems. Based on the simulation studies
carried out on the distribution system, the proposed scheme has been
found to be simple, accurate and easy to apply to solve the multiobjective
volt/var control optimization problem of the distribution
system with dispersed generation.
Abstract: The integral form of equations of motion of composite
beams subjected to varying time loads are discretized using a
developed finite element model. The model consists of a straight five
node twenty-two degrees of freedom beam element. The stability
analysis of the beams is studied by solving the matrix form
characteristic equations of the system. The principle of virtual work
and the first order shear deformation theory are employed to analyze
the beams with large deformation and small strains. The regions of
dynamic instability of the beam are determined by solving the
obtained Mathieu form of differential equations. The effects of nonconservative
loads, shear stiffness, and damping parameters on
stability and response of the beams are examined. Several numerical
calculations are presented to compare the results with data reported
by other researchers.
Abstract: This study is aimed to investigate feasibility of the
aerobic biological process to treat oily wastewater from palm oil food
industry. Effect of aeration and sludge concentrations are studied.
Raw sludge and raw wastewater was mixed and acclimatized for five
days in a stirred tank reactor. The aeration rate (no aeration, low;
1.5L/min and high rate; 2L/min) and sludge concentration (3675,
7350, and 11025mg/L of VSS) were varied. Responses of process
were pH, COD, oil and grease, VSS, and PHB content. It was found
that the treatment can remove 85.1 to 97.1 % of COD and remove
12.9 to 54.8% of oil & grease. The PHB yield was found to be within
0.15% to 2.4% as PHB/VSS ratio and 0.01% to 0.12% as PHB/COD
removed. The higher aeration results a high COD removal and oil &
grease removal, while experiment without aeration gives better PHB
yield. Higher sludge concentrations (11025mg/L VSS) give higher
removal of oil & grease while moderate sludge concentration
(7350mg/L VSS) give better result in COD removal. Higher PHB
yield is obtained in low sludge concentration (3675mg/L).
Abstract: For sterilization of Phalaenopsis culture medium without autoclaving, selected single sterilizing agents and in combinations were added to a 25ml Hyponex medium in a 120ml glass container. Treated liquid and solid media, supplemented with sterilizing agents, were compared to a control medium, autoclaved at 121°C for 15min. It was found that 90(L of 10% povidone-iodine, 150(L of 5.25% sodium hypochlorite, 150(L of 2% mercurochrome, 90(L of 2.5% iodine + 2.5% potassium iodine in combination with 10% providone-iodine (1:3) and 30(L of 2.5% iodine + 2.5% potassium iodide in combination with 2% mercurochrome showed 100% sterile conditions in liquid medium but provided 75, 100, 50, 75 and 80% sterile conditions, respectively, in solid medium. For growth of Phalaenopsis protocorms, 90(L of 10% povidone-iodine in liquid Hyponex medium gave the comparable growth of protocorms to control medium while 150(L of 5.25% sodium hypochlorite in solid medium provided the promising growth of protocorms. Growth of protocorms, whole fresh weight, numbers of leaf and root, root length and number of protocorm-like bodies, was discussed.
Abstract: Estimation of natural frequency of structures is very
important and isn-t usually calculated simply and sometimes
complicated. Lack of knowledge about that caused hard damage and
hazardous effects.
In this paper, with using from two different models in FEM
method and based on hydrodynamic mass of fluids, natural frequency
of an especial bearing (Fig. 1) in an electric field (or, a periodic
force) is calculated in different stiffness and different geometric. In
final, the results of two models and analytical solution are compared.
Abstract: Lignocellulosic materials are considered the most
abundant renewable resource available for the Bioethanol
Production. Water Hyacinth is one of potential raw material of the
world-s worst aquatic plant as a feedstock to produce Bioethanol.
The purposed this research is obtain reduced of matter for
biodegradation lignin in Biological pretreatment with White Rot
Fungi eg. Phanerochaete Chrysosporium using Solid state
Fermentation methods. Phanerochaete Chrysosporium is known to
have the best ability to degraded lignin, but simultaneously it can also
degraded cellulose and hemicelulose. During 8 weeks incubation,
water hyacinth occurred loss of weight reached 34,67%, while loss
of lignin reached 67,21%, loss of cellulose reached 11,01% and loss
of hemicellulose reached 36,56%. The kinetic of losses lignin using
regression linear plot, the results is obtained constant rate (k) of
reduction lignin is -0.1053 and the equation of reduction of lignin
is y = wo - 0, 1.53 x
Abstract: In this paper the complete rotor system including
elastic shaft with distributed mass, allowing for the effects of oil film
in bearings. Also, flexibility of foundation is modeled. As a whole
this article is a relatively complete research in modeling and
vibration analysis of rotor considering gyroscopic effect, damping,
dependency of stiffness and damping coefficients on frequency and
solving the vibration equations including these parameters. On the
basis of finite element method and utilizing four element types
including element of shaft, disk, bearing and foundation and using
MATLAB, a computer program is written. So the responses in
several cases and considering different effects are obtained. Then the
results are compared with each other, with exact solutions and results
of other papers.
Abstract: In this investigation, anatase TiO2 thin films were
grown by radio frequency magnetron sputtering on glass substrates at
a high sputtering pressure and room temperature. The anatase films
were then annealed at 300-600 °C in air for a period of 1 hour. To
examine the structure and morphology of the films, X-ray diffraction
(XRD) and atomic force microscopy (AFM) methods were used
respectively. From X-ray diffraction patterns of the TiO2 films, it was
found that the as-deposited film showed some differences compared
with the annealed films and the intensities of the peaks of the
crystalline phase increased with the increase of annealing
temperature. From AFM images, the distinct variations in the
morphology of the thin films were also observed. The optical
constants were characterized using the transmission spectra of the
films obtained by UV-VIS-IR spectrophotometer. Besides, optical
thickness of the film deposited at room temperature was calculated
and cross-checked by taking a cross-sectional image through SEM.
The optical band gaps were evaluated through Tauc model. It was
observed that TiO2 films produced at room temperatures exhibited
high visible transmittance and transmittance decreased slightly with
the increase of annealing temperatures. The films were found to be
crystalline having anatase phase. The refractive index of the films
was found from 2.31-2.35 in the visible range. The extinction
coefficient was nearly zero in the visible range and was found to
increase with annealing temperature. The allowed indirect optical
band gap of the films was estimated to be in the range from 3.39 to
3.42 eV which showed a small variation. The allowed direct band
gap was found to increase from 3.67 to 3.72 eV. The porosity was
also found to decrease at a higher annealing temperature making the
film compact and dense.
Abstract: Fertilization plays an important role in crop growth and soil improvement. This study was conducted to determine the best fertilization system for wheat production. Experiments were arranged in a complete block design with three replications in two years. Main plots consisted of six methods of fertilization including (N1): farmyard manure; (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers and (N6): control were arranged in sub plots. The addition of compost or farm yard manure significantly increased the soil microbial biomass carbon in comparison to the chemical fertilizer. The dehydrogenase, phosphatase and urease activities in the N3 treatment were significantly lower than in the farm yard manure and compost treatments.
Abstract: This experiment was conducted in attempt of
improving hydrodynamic efficiency of the propulsion mechanism by
installing a spring to the wing so that the opening angle of the wing in
one stroke can be changed automatically, compared to the existing
method of fixed maximum opening angle in Weis-Fogh type ship
propulsion mechanism. Average thrust coefficient was almost fixed
with all velocity ratio with the prototype, but with the spring type,
thrust coefficient increased sharply as velocity ratio increased.
Average propulsive efficiency was larger with bigger opening angle in
the prototype, but in the spring type, the one with smaller spring
coefficient had larger value. In the range over 1.0 in velocity ratio
where big thrust can be generated, spring type had more than twice of
propulsive efficiency increase compared to the prototype.
Abstract: This paper presents the theoretical investigation of a
slotted patch antenna. The main objective of proposed work is to
obtain a large bandwidth antenna with reduced size. The antenna has
a compact size of 21.1mm x 20.25mm x 8.5mm. Two designs with
minor variation are studied which provide wide impedance
bandwidths of 24.056% and 25.63% respectively with the use of
parasitic elements when excited by a probe feed. The advantages of
this configuration are its compact size and the wide range of
frequencies covered. A parametric study is also conducted to
investigate the characteristics of the antenna under different
conditions. The measured return loss and radiation pattern indicate
the suitability of this design for WLAN applications, namely, Wi-
Max, 802.11a/b/g and ISM bands.
Abstract: The present study was designed to demonstrate the seasonal variations in physico-chemical parameters of fish farm at Govt. Nursery Unit, Muzaffargarh, Department of Fisheries Govt. of Punjab, Pakistan for a period of eight months from January to August 2008. Water samples were collected on fifteen days basis and have been analyzed for estimation of Air temperature, Water temperature, Light penetration, pH, Total dissolved oxygen, Clouds, Carbonates, Bicarbonates, Total carbonates, Total dissolved solids, Chlorides, Calcium and Hardness. Seasonal fluctuations were observed in all the physico-chemical parameters of fish farm. The overall physicochemical parameters of fish pond water remained within the tolerable range throughout the study period.
Abstract: In this paper, we present a technical and an economic
assessment of several sources of renewable energy in Saudi Arabia;
mainly solar, wind, hydro and biomass. We analyze the
environmental and climatic conditions in relation to these sources
and give an overview of some of the existing clean energy
technologies. Using standardized cost and efficiency data, we carry
out a cost benefit analysis to understand the economic factors
influencing the sustainability of energy production from renewable
sources in light of the energy cost and demand in the Saudi market.
Finally, we take a look at the Saudi petroleum industry and the
existing sources of conventional energy and assess the potential of
building a successful market for renewable energy under the
constraints imposed by the flow of subsidized cheap oil. We show
that while some renewable energy resources are well suited for
distributed or grid connected generation in the kingdom, their
viability is greatly undercut by the well developed and well
capitalized oil industry.
Abstract: Using 1km grid datasets representing monthly mean
precipitation, monthly mean temperature, and dry matter production
(DMP), we considered the regional plant production ability in
Southeast and South Asia, and also employed pixel-by-pixel
correlation analysis to assess the intensity of relation between climate
factors and plant production. While annual DMP in South Asia was
approximately less than 2,000kg, the one in most part of Southeast
Asia exceeded 2,500 - 3,000kg. It suggested that plant production in
Southeast Asia was superior to South Asia, however, Rain-Use
Efficiency (RUE) representing dry matter production per 1mm
precipitation showed that inland of Indochina Peninsula and India
were higher than islands in Southeast Asia. By the results of
correlation analysis between climate factors and DMP, while the area
in most parts of Indochina Peninsula indicated negative correlation
coefficients between DMP and precipitation or temperature, the area
in Malay Peninsula and islands showed negative correlation to
precipitation and positive one to temperature, and most part of India
dominating South Asia showed positive to precipitation and negative
to temperature. In addition, the areas where the correlation coefficients
exceeded |0.8| were regarded as “susceptible" to climate factors, and
the areas smaller than |0.2| were “insusceptible". By following the
discrimination, the map implying expected impacts by climate change
was provided.
Abstract: Voice over Internet Protocol (VoIP) application or commonly known as softphone has been developing an increasingly large market in today-s telecommunication world and the trend is expected to continue with the enhancement of additional features. This includes leveraging on the existing presence services, location and contextual information to enable more ubiquitous and seamless communications. In this paper, we discuss the concept of seamless session transfer for real-time application such as VoIP and IPTV, and our prototype implementation of such concept on a selected open source VoIP application. The first part of this paper is about conducting performance evaluation and assessments across some commonly found open source VoIP applications that are Ekiga, Kphone, Linphone and Twinkle so as to identify one of them for implementing our design of seamless session transfer. Subjective testing has been carried out to evaluate the audio performance on these VoIP applications and rank them according to their Mean Opinion Score (MOS) results. The second part of this paper is to discuss on the performance evaluations of our prototype implementation of session transfer using Linphone.
Abstract: In this study the mixed mode fracture mechanics
parameters were investigated for high tensile steel butt welded joint
based on modified Arcan test and finite element analysis was used to
evaluate the effect of crack length on fracture criterion. The nondimensional
stress intensity factors, strain energy release rates and Jintegral
energy on crack tip were obtained for various in-plane
loading combinations on Arcan specimen starting from pure mode-I
to pure mode-II loading conditions. The specimen and apparatus were
modeled by finite element method and analyzed under various
loading angles (between 0 to 90 degrees with 15 degree interval) to
simulate the pure mode-I, II and mixed mode fracture. Since the
analytical results are independent from elasticity modules for
isotropic materials, therefore the results in elastic fields can be used
for Arcan specimens. The main objective of this study was to
evaluate the geometric calibration factors for modified Arcan test
specimen in order to obtain fracture toughness under mixed mode
loading conditions.