Abstract: Turbulence studies were made in the wake of a rotating
circular cylinder in a uniform free stream. The interest was to
examine the turbulence properties at the suppression of periodicity in
vortex formation process. An experimental study of the turbulent near
wake of a rotating circular cylinder was made at a Reynolds number
of 9000 for velocity ratios, λ between 0 and 2.7. Hot-wire
anemometry and particle image velocimetry results indicate that the
rotation of the cylinder causes significant changes in the vortical
activities. The turbulence quantities are getting smaller as λ increases
due to suppression of coherent vortex structures.
Abstract: The mesoporous MoO3/γ-Al2O3 catalyst was prepared
by incipient wetness impregnation method aiming to investigate the
effect of drying method and molybdenum content on the catalyst
property and performance towards the oxidation of benzothiophene
(BT), dibenzothiophene (DBT) and 4,6-dimethyle dibenzothiophene
(4,6-DMDBT) with H2O2 for deep oxidative desulfurization of diesel
fuel. The catalyst was characterized by XRD, BET, BJH and SEM
method. The catalyst with 10wt.% and 15wt.% Mo content represent
same optimum performance for DBT and 4,6-DMDBT removal, but
a catalyst with 10wt.% Mo has higher efficiency than 15wt.% Mo for
BT conversion. The SEM images show that use of rotary evaporator
in drying step reaches a more homogenous impregnation. The
oxidation reactivity of different sulfur compounds was studied which
followed the order of DBT>4,6-DMDBT>>BT.
Abstract: By incorporating a prey refuge, this paper proposes new discrete Leslie–Gower predator–prey systems with and without Allee effect. The existence of fixed points are established and the stability of fixed points are discussed by analyzing the modulus of characteristic roots.
Abstract: Liposomal magnetofection is a simple, highly efficient
technology for cell transfection, demonstrating better outcome than a
number of other common gene delivery methods. However,
aggregate complexes distribution over the cell surface is non-uniform
due to the gradient of the permanent magnetic field. The aim of this
study was to estimate the efficiency of liposomal magnetofection for
prostate carcinoma PC3 cell line using newly designed device,
“DynaFECTOR", ensuring magnetofection in a dynamic gradient
magnetic field. Liposomal magnetofection in a dynamic gradient
magnetic field demonstrated the highest transfection efficiency for
PC3 cells – it increased for 21% in comparison with liposomal
magnetofection and for 42% in comparison with lipofection alone.
The optimal incubation time under dynamic magnetic field for PC3
cell line was 5 minutes and the optimal rotation frequency of
magnets – 5 rpm. The new approach also revealed lower cytotoxic
effect to cells than liposomal magnetofection.
Abstract: E-learning is not restricted to the use of new technologies for the online content, but also induces the adoption of new approaches to improve the quality of education. This quality depends on the ability of these approaches (technical and pedagogical) to provide an adaptive learning environment. Thus, the environment should include features that convey intentions and meeting the educational needs of learners by providing a customized learning path to acquiring a competency concerned In our proposal, we believe that an individualized learning path requires knowledge of the learner. Therefore, it must pass through a personalization of diagnosis to identify precisely the competency gaps to fill, and reduce the cognitive load To personalize the diagnosis and pertinently measure the competency gap, we suggest implementing the formative assessment in the e-learning environment and we propose the introduction of a pre-regulation process in the area of formative assessment, involving its individualization and implementation in e-learning.
Abstract: Temperature, relative humidity and overhygroscopic
moisture fields in a sandstone wall provided with interior thermal
insulation were calculated in order to assess the hygric performance
of the retrofitted wall. Computational simulations showed that during
the time period of 10 years which was subject of investigation no
overhygroscopic moisture appeared in the analyzed building
envelope so that it performed in a satisfactory way from the hygric
point of view.
Abstract: Direct fermentation of 226 white rose tapioca stem to
ethanol by Fusarium oxysporum was studied in a batch reactor.
Fermentation of ethanol can be achieved by sequential pretreatment
using dilute acid and dilute alkali solutions using 100 mesh tapioca
stem particles. The quantitative effects of substrate concentration, pH
and temperature on ethanol concentration were optimized using a full
factorial central composite design experiment. The optimum process
conditions were then obtained using response surface methodology.
The quadratic model indicated that substrate concentration of 33g/l,
pH 5.52 and a temperature of 30.13oC were found to be optimum for
maximum ethanol concentration of 8.64g/l. The predicted optimum
process conditions obtained using response surface methodology was
verified through confirmatory experiments. Leudeking-piret model
was used to study the product formation kinetics for the production
of ethanol and the model parameters were evaluated using
experimental data.
Abstract: On the basis of Bayesian inference using the
maximizer of the posterior marginal estimate, we carry out phase
unwrapping using multiple interferograms via generalized mean-field
theory. Numerical calculations for a typical wave-front in remote
sensing using the synthetic aperture radar interferometry, phase
diagram in hyper-parameter space clarifies that the present method
succeeds in phase unwrapping perfectly under the constraint of
surface- consistency condition, if the interferograms are not corrupted
by any noises. Also, we find that prior is useful for extending a phase
in which phase unwrapping under the constraint of the
surface-consistency condition. These results are quantitatively
confirmed by the Monte Carlo simulation.
Abstract: In this paper, a new pseudo affine projection (AP)
algorithm based on Gauss-Seidel (GS) iterations is proposed for
acoustic echo cancellation (AEC). It is shown that the algorithm is
robust against near-end signal variations (including double-talk).
Abstract: We present the results of a case study aiming to assess the reflection of the tourism community in the Web and its usability to propose new ways to communicate visually. The wealth of information contained in the Web and the clear facilities to communicate personals points of view makes of the social web a new space of exploration. In this way, social web allow the sharing of information between communities with similar interests. However, the tourism community remains unexplored as is the case of the information covered in travel stories. Along the Web, we find multiples sites allowing the users to communicate their experiences and personal points of view of a particular place of the world. This cultural heritage is found in multiple documents, usually very little supplemented with photos, so they are difficult to explore due to the lack of visual information. This paper explores the possibility of analyzing travel stories to display them visually on maps and generate new knowledge such as patterns of travel routes. This way, travel narratives published in electronic formats can be very important especially to the tourism community because of the great amount of knowledge that can be extracted. Our approach is based on the use of a Geoparsing Web Service to extract geographic coordinates from travel narratives in order to draw the geo-positions and link the documents into a map image.
Abstract: Gamboge disorder (GD) or fruit damage by the yellow sap is a major problem in mangosteen. Mangosteen plants varied in the level of GD, from very low or non GD to low, moderate and high GD. However it was difficult to differentiate between GD and non GD plants because evaluation of the disorder is strongly influenced by environment. In this study we investigated the usefulness of primer designed from bioinformatics related to cell wall strength, termed as MCWS, to predict GD. Plant materials used were 28 mangosteen plants selected based on percentage of GD categorized as high, moderate, low and very low or non GD. The result showed that the specific DNA fragments were absent in the high GD accessions. The MCWS marker suggests as a novel polymorphic marker for GD in mangosteen as well as a marker for detect variability in mangosteen as apomictic plant.
Abstract: Two novel hydrodesulfurization (HDS) catalysts:
FeN4/C and FeN2/C, were prepared using an impregnation-pyrolysis
method. The two materials were investigated as catalysts for
hydrodesulfurization (HDS) and hydrodearomitization (HDA) of
model compounds. The turnover frequency of the two FeN catalysts
is comparable to (FeN4/C) or even higher (FeN2/C) than that of
MoNi/Al2O3. The FeN4/C catalyst also exhibited catalytic activity
toward HDA.
Abstract: In CMOS integrated circuit design there is a trade-off between static power consumption and technology scaling. Recently, the power density has increased due to combination of higher clock speeds, greater functional integration, and smaller process geometries. As a result static power consumption is becoming more dominant. This is a challenge for the circuit designers. However, the designers do have a few methods which they can use to reduce this static power consumption. But all of these methods have some drawbacks. In order to achieve lower static power consumption, one has to sacrifice design area and circuit performance. In this paper, we propose a new method to reduce static power in the CMOS VLSI circuit using Variable Body Biasing technique without being penalized in area requirement and circuit performance.
Abstract: The importance for manipulating an incorporated
scaffold and directing cell behaviors is well appreciated for tissue
engineering. Here, we developed newly nano-topographic oxidized
silicon nanosponges capable of being various chemical modifications
to provide much insight into the fundamental biology of how cells
interact with their surrounding environment in vitro. A wet etching
technique is exerted to allow us fabricated the silicon nanosponges in a
high-throughput manner. Furthermore, various organo-silane
chemicals enabled self-assembled on the surfaces by vapor deposition.
We have found that Chinese hamster ovary (CHO) cells displayed
certain distinguishable morphogenesis, adherent responses, and
biochemical properties while cultured on these chemical modified
nano-topographic structures in compared with the planar oxidized
silicon counterparts, indicating that cell behaviors can be influenced
by certain physical characteristic derived from nano-topography in
addition to the hydrophobicity of contact surfaces crucial for cell
adhesion and spreading. Of particular, there were predominant
nano-actin punches and slender protrusions formed while cells were
cultured on the nano-topographic structures. This study shed potential
applications of these nano-topographic biomaterials for controlling
cell development in tissue engineering or basic cell biology research.
Abstract: Determination of wellbore problems during a
production/injection process might be evaluated thorough
temperature log analysis. Other applications of this kind of log
analysis may also include evaluation of fluid distribution analysis
along the wellbore and identification of anomalies encountered
during production/injection process. While the accuracy of such
prediction is paramount, the common method of determination of a
wellbore temperature log includes use of steady-state energy balance
equations, which hardly describe the real conditions as observed in
typical oil and gas flowing wells during production operation; and
thus increase level of uncertainties. In this study, a practical method
has been proposed through development of a simplified semianalytical
model to apply for predicting temperature profile along the
wellbore. The developed model includes an overall heat transfer
coefficient accounting all modes of heat transferring mechanism,
which has been focused on the prediction of a temperature profile as
a function of depth for the injection/production wells. The model has
been validated with the results obtained from numerical simulation.
Abstract: The present paper concerns with the influence of fiber
packing on the transverse plastic properties of metal matrix
composites. A micromechanical modeling procedure is used to
predict the effective mechanical properties of composite materials at
large tensile and compressive deformations. Microstructure is
represented by a repeating unit cell (RUC). Two fiber arrays are
considered including ideal square fiber packing and random fiber
packing defined by random sequential algorithm. The
micromechanical modeling procedure is implemented for
graphite/aluminum metal matrix composite in which the
reinforcement behaves as elastic, isotropic solids and the matrix is
modeled as an isotropic elastic-plastic solid following the von Mises
criterion with isotropic hardening and the Ramberg-Osgood
relationship between equivalent true stress and logarithmic strain.
The deformation is increased to a considerable value to evaluate both
elastic and plastic behaviors of metal matrix composites. The yields
strength and true elastic-plastic stress are determined for
graphite/aluminum composites.
Abstract: In this study, synthesis of biomemitic patterned nano
hydroxyapatite-starch biocomposites using different concentration of
starch to evaluate effect of polymer alteration on biocomposites
structural properties has been reported. Formation of hydroxyapatite
nano particles was confirmed by X-ray diffraction (XRD) and Fourier
transform infrared spectroscopy (FT-IR). Size and morphology of the
samples were characterized using scanning and transmission electron
microscopy (SEM and TEM). It seems that by increasing starch
content, the more active site of polymer (oxygen atoms) can be
provided for interaction with Ca2+ followed by phosphate and
hydroxyl group.
Abstract: Post cracking behavior and load –bearing capacity of
the steel fiber reinforced high-strength concrete (SFRHSC) are
dependent on the number of fibers are crossing the weakest crack
(bridged the crack) and their orientation to the crack surface. Filling
the mould by SFRHSC, fibers are moving and rotating with the
concrete matrix flow till the motion stops in each internal point of the
concrete body. Filling the same mould from the different ends
SFRHSC samples with the different internal structures (and different
strength) can be obtained. Numerical flow simulations (using Newton
and Bingham flow models) were realized, as well as single fiber
planar motion and rotation numerical and experimental investigation
(in viscous flow) was performed. X-ray pictures for prismatic
samples were obtained and internal fiber positions and orientations
were analyzed. Similarly fiber positions and orientations in cracked
cross-section were recognized and were compared with numerically
simulated. Structural SFRHSC fracture model was created based on
single fiber pull-out laws, which were determined experimentally.
Model predictions were validated by 15x15x60cm prisms 4 point
bending tests.
Abstract: Electrochemical-oxidation of Reactive Black-5 (RB- 5) was conducted for degradation using DSA type Ti/RuO2-SnO2- Sb2O5 electrode. In the study, for electro-oxidation, electrode was indigenously fabricated in laboratory using titanium as substrate. This substrate was coated using different metal oxides RuO2, Sb2O5 and SnO2 by thermal decomposition method. Laboratory scale batch reactor was used for degradation and decolorization studies at pH 2, 7 and 11. Current density (50mA/cm2) and distance between electrodes (8mm) were kept constant for all experiments. Under identical conditions, removal of color, COD and TOC at initial pH 2 was 99.40%, 55% and 37% respectively for initial concentration of 100 mg/L RB-5. Surface morphology and composition of the fabricated electrode coatings were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) respectively. Coating microstructure was analyzed by X-ray diffraction (XRD). Results of this study further revealed that almost 90% of oxidation occurred within 5-10 minutes.
Abstract: Purpose of this paper is two-folded. At first it explains
the major problems that are causing stagnation in brownfield
redevelopment. In addition, these problems given the context of the
present multi-actor built environment are becoming more complex to
observe. Therefore, this paper suggests also a prospective decisionmaking
approach that is the most appropriate to observe and react on
the given stagnation problems. Such an approach should be regarded
as prescriptive-interactive decision-making approach, a barely
established branch. This approach should offer models that have
prescriptive as well as an interactive component enabling them to
successfully cope with the multi-actor environment. Overall, this
paper provides up-to-date insight on the brownfield stagnation by
gradually introducing the nowadays major problems and offers a
prospective decision-making approach how these problems could be
tackled.