Abstract: Within this paper, latest results on processing of energetic nanomaterials by means of the Spray Flash Evaporation technique are presented. This technology constitutes a highly effective and continuous way to prepare fascinating materials on the nano- and micro-scale. Within the process, a solution is set under high pressure and sprayed into an evacuated atomization chamber. Subsequent ultrafast evaporation of the solvent leads to an aerosol stream, which is separated by cyclones or filters. No drying gas is required, so the present technique should not be confused with spray dying. Resulting nanothermites, insensitive explosives or propellants and compositions are foreseen to replace toxic (according to REACH) and very sensitive matter in military and civil applications. Diverse examples are given in detail: nano-RDX (n-Cyclotrimethylentrinitramin) and nano-aluminum based systems, mixtures (n-RDX/n-TNT - trinitrotoluene) or even cocrystalline matter like n-CL-20/HMX (Hexanitrohexaazaisowurtzitane/ Cyclotetra-methylentetranitramin). These nanomaterials show reduced sensitivity by trend without losing effectiveness and performance. An analytical study for material characterization was performed by using Atomic Force Microscopy, X-Ray Diffraction, and combined techniques as well as spectroscopic methods. As a matter of course, sensitivity tests regarding electrostatic discharge, impact, and friction are provided.
Abstract: For the last decade, researchers have started to focus
their interest on Multicast Group Key Management Framework. The
central research challenge is secure and efficient group key
distribution. The present paper is based on the Bit model based
Secure Multicast Group key distribution scheme using the most
popular absolute encoder output type code named Gray Code. The
focus is of two folds. The first fold deals with the reduction of
computation complexity which is achieved in our scheme by
performing fewer multiplication operations during the key updating
process. To optimize the number of multiplication operations, an
O(1) time algorithm to multiply two N-bit binary numbers which
could be used in an N x N bit-model of reconfigurable mesh is used
in this proposed work. The second fold aims at reducing the amount
of information stored in the Group Center and group members while
performing the update operation in the key content. Comparative
analysis to illustrate the performance of various key distribution
schemes is shown in this paper and it has been observed that this
proposed algorithm reduces the computation and storage complexity
significantly. Our proposed algorithm is suitable for high
performance computing environment.
Abstract: Liver segmentation from medical images poses more
challenges than analogous segmentations of other organs. This
contribution introduces a liver segmentation method from a series of
computer tomography images. Overall, we present a novel method for
segmenting liver by coupling density matching with shape priors.
Density matching signifies a tracking method which operates via
maximizing the Bhattacharyya similarity measure between the
photometric distribution from an estimated image region and a model
photometric distribution. Density matching controls the direction of
the evolution process and slows down the evolving contour in regions
with weak edges. The shape prior improves the robustness of density
matching and discourages the evolving contour from exceeding liver’s
boundaries at regions with weak boundaries. The model is
implemented using a modified distance regularized level set (DRLS)
model. The experimental results show that the method achieves a
satisfactory result. By comparing with the original DRLS model, it is
evident that the proposed model herein is more effective in addressing
the over segmentation problem. Finally, we gauge our performance of
our model against matrices comprising of accuracy, sensitivity, and
specificity.
Abstract: Machine visualization is an area of interest with fast
and progressive development. We present a method of machine
visualization which will be applicable in real industrial conditions
according to current needs and demands. Real factory data were
obtained in a newly built research plant. Methods described in this
paper were validated on a case study. Input data were processed and
the virtual environment was created. The environment contains
information about dimensions, structure, disposition, and function.
Hardware was enhanced by modular machines, prototypes, and
accessories. We added functionalities and machines into the virtual
environment. The user is able to interact with objects such as testing
and cutting machines, he/she can operate and move them. Proposed
design consists of an environment with two degrees of freedom of
movement. Users are in touch with items in the virtual world which
are embedded into the real surroundings. This paper describes development of the virtual environment. We
compared and tested various options of factory layout virtualization
and visualization. We analyzed possibilities of using a 3D scanner in
the layout obtaining process and we also analyzed various virtual
reality hardware visualization methods such as: Stereoscopic (CAVE)
projection, Head Mounted Display (HMD) and augmented reality
(AR) projection provided by see-through glasses.
Abstract: The agenda of showing the scheduled time for
performing certain tasks is known as timetabling. It is widely used in
many departments such as transportation, education, and production.
Some difficulties arise to ensure all tasks happen in the time and
place allocated. Therefore, many researchers invented various
programming models to solve the scheduling problems from several
fields. However, the studies in developing the general integer
programming model for many timetabling problems are still
questionable. Meanwhile, this thesis describes about creating a
general model which solves different types of timetabling problems
by considering the basic constraints. Initially, the common basic
constraints from five different fields are selected and analyzed. A
general basic integer programming model was created and then
verified by using the medium set of data obtained randomly which is
much similar to realistic data. The mathematical software, AIMMS
with CPLEX as a solver has been used to solve the model. The model
obtained is significant in solving many timetabling problems easily
since it is modifiable to all types of scheduling problems which have
same basic constraints.
Abstract: Anaerobic digestion is a well-known technique for
sustainable energy recovery from sewage sludge. However, sewage
sludge digestion is restricted due to certain factors. Pre-treatment
methods have been established in various publications as a promising
technique to improve the digestibility of the sewage sludge and to
enhance the biogas generated which can be used for energy recovery.
In this study, continuous flow microwave (MW) pre-treatment with
different intensities were compared by using 5 L semi-continuous
digesters at a hydraulic retention time of 27 days. We focused on the
effects of MW at different intensities on the sludge solubilization,
sludge digestibility, and biogas production of the untreated and MW
pre-treated sludge. The MW pre-treatment demonstrated an increase
in the ratio of soluble chemical oxygen demand to total chemical
oxygen demand (sCOD/tCOD) and volatile fatty acid (VFA)
concentration. Besides that, the total volatile solid (TVS) removal
efficiency and tCOD removal efficiency also increased during the
digestion of the MW pre-treated sewage sludge compared to the
untreated sewage sludge. Furthermore, the biogas yield also
subsequently increases due to the pre-treatment effect. A higher MW
power level and irradiation time generally enhanced the biogas
generation which has potential for sustainable energy recovery from
sewage treatment plant. However, the net energy balance tabulation
shows that the MW pre-treatment leads to negative net energy production.
Abstract: Anogeissus leiocarpus (Combretaceae) is well known
for its medicinal uses in African traditional medicine, for treating
many human diseases mainly skin diseases and infections. Mycetoma
disease is a fungal and/ or bacterial skininfection, mainly cause by
Madurella mycetomatis fungus. This study was carried out in vitro to
investigate the antifungal activity of Anogeissus leiocarpus leaf
extracts against the isolated pathogenic Madurella mycetomatis, by
using the NCCLS modified method compared to Ketoconazole
standard drug, and MTT assay. The bioactive fraction was subjected
to chemical analysis implementing different chromatographic
analytical methods (TLC, HPLC, and LC-MS/MS). The results
showed significance antifungal activity of A. leiocarpus leaf extracts
against the isolated pathogenic M. mycetomatis, compared to negative
and positive controls. The chloroform fraction showed the highest
antifungal activity. The chromatographic analysis of the chloroform
fraction with the highest activity showed the presence of important
bioactive compounds such as ellagic and flavellagic acids derivatives,
flavonoids and stilbenoid, which are well known for their antifungal
activity.
Abstract: The post-rain puddles problem that occurs in the first
yard of Prambanan Temple are often disturbing visitor activity. A
poodle layer and a drainage system had ever built to avoid such a
problem, but puddles still did not stop appearing after rain.
Permeability parameter needs to be determined by using a simpler
procedure to find exact method of solution. The instrument modelling
was proposed according to the development of field permeability
testing instrument. This experiment used a proposed Constant
Discharge method. Constant Discharge method used a tube poured
with constant water flow from unsaturated until saturated soil
condition. Volumetric water content (θ) were monitored by soil
moisture measurement device. The results were correlations between
k and θ which were drawn by numerical approach from Van
Genutchen model. Parameters θr optimum value obtained from the
test was at very dry soil. Coefficient of permeability with a density of
19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6
cm/sec (Sr=68%) until 9.98 x 10-4 cm/sec (Sr=82%). The equipment
and testing procedure developed in this research was quite effective,
simple and easy to be implemented on determining field soil
permeability coefficient value of sandy soil. Using constant discharge
method in proposed permeability test, value of permeability
coefficient under unsaturated condition can be obtained without
establish soil water characteristic curve.
Abstract: In order to investigate the prebiotic potential of
oligosaccharides prepared by chemical hydrolysis of water-soluble
polysaccharides (WSP) from Zizyphus lotus leaves, the effect of
oligosaccharides on bacterial growth was studied. The chemical
composition of WSP was evaluated by colorimetric assays revealed
the average values: 7.05±0.73% proteins and 86.21±0.74%
carbohydrates, among them 64.81±0.42% is neutral sugar and the rest
16.25±1.62% is uronic acids. The characterization of
monosaccharides was determined by high performance anion
exchange chromatography with pulsed amperometric detection
(HPAEC-PAD) was found to be composed of galactose (23.95%),
glucose (21.30%), rhamnose (20.28%), arabinose (9.55%), and
glucuronic acid (22.95%). The effects of oligosaccharides on the
growth of lactic acid bacteria were compared with those of fructooligosaccharide
(RP95). The oligosaccharides concentration was
1g/L of Man, Rogosa, Sharpe broth. Bacterial growth was assessed
during 2, 4.5, 6.5, 9, 12, 16 and 24 h by measuring the optical density
of the cultures at 600 nm (OD600) and pH values. During
fermentation, pH in broth cultures decreased from 6.7 to 5.87±0.15.
The enumeration of lactic acid bacteria indicated that
oligosaccharides led to a significant increase in bacteria (P≤0.05)
compared to the control. The fermentative metabolism appeared to be
faster on RP95 than on oligosaccharides from Zizyphus lotus leaves.
Both RP95 and oligosaccharides showed clear prebiotic effects, but
had differences in fermentation kinetics because of to the different
degree of polymerization. This study shows the prebiotic
effectiveness of oligosaccharides, and provides proof for the selection
of leaves of Zizyphus lotus for use as functional food ingredients.
Abstract: In the recent past, discussing about sex among
children and youths was frowned at by traditional norms and as such
sexual discussions and behavior were approached with great respect.
Things are actually falling apart with the increasing number of young
people that engage in premarital sex. Due to lack of experience and
sex education, many young people are becoming increasingly
exposed to the risk of HIV infection. In the light of the above, this
study discussed premarital sex, HIV, and use of condom among
youths in Nigeria. Data for this study came from 2013 Nigeria
Demographic and Health Survey and other secondary data. The
survey revealed that only 18.5 percent of young women that had sex
in the 12 months preceding the survey used condom. Out of 3306
never-married sexually active men and women, 1728 representing 52
percent live in urban areas and 43 percent of them did not use
condom during sexual intercourse in the 12 months preceding the
survey. This study concludes that for there to be reduction in
prevalence of HIV/AIDS among Nigerian youths, there is need for
concerted effort to be made towards educating youths on the
expedient of the use of condom during sexual intercourse.
Abstract: Lateral Geniculate Nucleus (LGN) is the relay center
in the visual pathway as it receives most of the input information
from retinal ganglion cells (RGC) and sends to visual cortex. Low
threshold calcium currents (IT) at the membrane are the unique
indicator to characterize this firing functionality of the LGN neurons
gained by the RGC input. According to the LGN functional
requirements such as functional mapping of RGC to LGN, the
morphologies of the LGN neurons were developed. During the
neurological disorders like glaucoma, the mapping between RGC and
LGN is disconnected and hence stimulating LGN electrically using
deep brain electrodes can restore the functionalities of LGN. A
computational model was developed for simulating the LGN neurons
with three predominant morphologies each representing different
functional mapping of RGC to LGN. The firings of action potentials
at LGN neuron due to IT were characterized by varying the
stimulation parameters, morphological parameters and orientation. A
wide range of stimulation parameters (stimulus amplitude, duration
and frequency) represents the various strengths of the electrical
stimulation with different morphological parameters (soma size,
dendrites size and structure). The orientation (0-1800) of LGN
neuron with respect to the stimulating electrode represents the angle
at which the extracellular deep brain stimulation towards LGN
neuron is performed. A reduced dendrite structure was used in the
model using Bush–Sejnowski algorithm to decrease the
computational time while conserving its input resistance and total
surface area. The major finding is that an input potential of 0.4 V is
required to produce the action potential in the LGN neuron which is
placed at 100 μm distance from the electrode. From this study, it can
be concluded that the neuroprostheses under design would need to
consider the capability of inducing at least 0.4V to produce action
potentials in LGN.
Abstract: Diets high in processed foods have been found to lack
essential micro-nutrients for optimum human development and
overall health. Some micro-nutrients such as copper (Cu) have been
found to enhance the inflammatory response through its oxidative
functions, thereby having a role in cardiovascular disease, metabolic
syndrome, diabetes and related complications. This research study
was designed to determine if food crops could be bio-fortified with
micro-nutrients by growing sprouts on mineral fortified fiber mats. In
the feasibility study described in this contribution, recycled cellulose
fibers and clay, saturated with either micro-nutrient copper ions or
copper nanoparticles, were converted to a novel mineral-cellulose
fiber carrier of essential micro-nutrient and of antimicrobial
properties. Seeds of Medicago sativa (alfalfa), purchased from a
commercial, organic supplier were germinated on engineered
cellulose fiber mats. After the appearance of the first leaves, the
sprouts were dehydrated and analyzed for Cu content. Nutrient
analysis showed ~2 increase in Cu of the sprouts grown on the fiber
mats with copper particles, and ~4 increase on mats with ionic copper
as compared to the control samples. This study illustrates the
potential for the use of engineered mats as a viable way to increase
the micro-nutrient composition of locally-grown food crops and the
need for additional research to determine the uptake, nutritional
implications and risks of micro-nutrient bio-fortification.
Abstract: Nature constantly changes as a result of human
necessities. This change mostly feels in natural water sources which
are reconstructed with an effect of dams and motorways. In other
respects, visual quality of the landscape gets a new and different
character during and after the construction of dams and motorways.
Changing and specialization new landscapes will be very important
to protection-usage balance to explore sustainable usage facilities.
The main cause of the selection of Artvin city is that it has very
important geographical location and one of the most attraction points
in the World with its biodiversity, conservation areas and natural
landscape characteristics. Many hydroelectric station and 7 dams are
situated, 3 of them have already been built on the Çoruh River in the
province of Artvin. As a result of dams, motorways route were reshaped
and the ways which have already changed because of
elevation is directly affected several of natural destruction. In
contrast, many different reservoirs in Coruh Basin provide new vista
point that has high visual quality. In this study, we would like to
evaluate with sustainable landscape design in 76 km river corridor,
which is mainly based on Deriner, Borçka and Muratlı Dams and
determination of their basin-lakes recreational potential and
opportunities. Lastly, we are going to give some suggestion about the
potential of the corridor.
Abstract: The current statuses of lifetime test of LaB6 hollow
cathode at the Lanzhou Institute of Physics (LIP), China, was
described. 5A LaB6 hollow cathode was design for LIPS-200 40mN
Xenon ion thruster, and it could be used for LHT-100 80 mN Hall
thruster, too. Life test of the discharge and neutralizer modes of LHC-5
hollow cathode were stared in October 2011, and cumulative operation
time reached 17,300 and 16,100 hours in April 2015, respectively. The
life of cathode was designed more than 11,000 hours. Parameters of
discharge and key structure dimensions were monitored in different
stage of life test indicated that cathodes were health enough. The test
will continue until the cathode cannot work or operation parameter is
not in normally. The result of the endurance test of cathode
demonstrated that the LaB6 hollow cathode is satisfied for the required
of thruster in life and performance.
Abstract: The objective of this work is to carryout critical
comparison of different actuation mechanisms like electrostatic,
thermal, piezoelectric, and magnetic with reference to a micro
cantilever. The relevant parameters like force generated,
displacement are compared in actuation methods. With these results,
helps in choosing the best actuation method for a particular
application. In this study, Comsol/Multiphysics software is used.
Modeling and simulation is done by considering the micro cantilever
of same dimensions as an actuator using all the above mentioned
actuation techniques. In addition to their small size, micro actuators
consume very little power and are capable of accurate results. In this
work, a comparison of actuation mechanisms is done to decide the
efficient system in micro domain.
Abstract: The paper discusses the problem of load transport
using farm tractors and road tractor units. This type of carriage of
goods is often done with farm vehicles. The tests were performed
with the PEMS equipment (Portable Emission Measurement System)
under actual traffic conditions. The vehicles carried a load of 20000
kg. This research method is one of the most desired because it
provides reliable information on the actual vehicle emissions and fuel
consumption (carbon balance method). For the tests, a route was
selected that simulated a trip from a small town to a food-processing
facility located in a city. The analysis of the obtained results gave a
clear answer as to what vehicles need to be used for carriage of this
type of cargo in terms of exhaust emissions and fuel consumption.
Abstract: Within Rapid Prototyping technologies are used many
types of materials. Many of them are recyclable but there are still as
plastic like, so practically they do not degrade in the landfill.
Polylactic acid (PLA) is one of the special plastic materials, which
are biodegradable and available for 3D printing within Fused
Deposition Modeling (FDM) technology. The question is, if the
mechanical properties of produced models are comparable to similar
technical plastic materials which are usual for prototype production.
Presented paper shows the experiments results for tensile strength
measurements for specimens prepared with different 3D printer
settings and model orientation. Paper contains also the comparison of
tensile strength values with values measured on specimens produced
by conventional technologies as injection moulding.
Abstract: Given the increase in the number of e-commerce sites,
the number of competitors has become very important. This means
that companies have to take appropriate decisions in order to meet the
expectations of their customers and satisfy their needs. In this paper,
we present a case study of applying LRFM (length, recency,
frequency and monetary) model and clustering techniques in the
sector of electronic commerce with a view to evaluating customers’
values of the Moroccan e-commerce websites and then developing
effective marketing strategies. To achieve these objectives, we adopt
LRFM model by applying a two-stage clustering method. In the first
stage, the self-organizing maps method is used to determine the best
number of clusters and the initial centroid. In the second stage, kmeans
method is applied to segment 730 customers into nine clusters
according to their L, R, F and M values. The results show that the
cluster 6 is the most important cluster because the average values of
L, R, F and M are higher than the overall average value. In addition,
this study has considered another variable that describes the mode of
payment used by customers to improve and strengthen clusters’
analysis. The clusters’ analysis demonstrates that the payment method is
one of the key indicators of a new index which allows to assess the
level of customers’ confidence in the company's Website.
Abstract: Numerical study of the static response of
homogeneous clay stratum considering a wide range of cohesion and
subject to foundation loads is presented. The linear elastic–perfectly
plastic constitutive relation with the von Mises yield criterion were
utilised to develop a numerically cost effective finite element model
for the soil while imposing a rigid body constrain to the foundation
footing. From the analyses carried out, estimate of the bearing
capacity factor, Nc as well as the ultimate load-carrying capacities of
these soils, effect of cohesion on foundation settlements, stress fields
and failure propagation were obtained. These are consistent with
other findings in the literature and hence can be a useful guide in
design of safe foundations in clay soils for buildings and other
structure.
Abstract: The purpose of this research is to investigate the
marketing mix that is perceived to be important for the small sized
hotels in Pattaya. This research provides insights through a review of
the marketing activities performed by the small sized hotels. Nine
owners & marketing manager of small sized hotels and resorts, all
local Chonburi people, were selected for an in-depth interview. The
research suggests that seven marketing mixes (e.g. Product, Price,
Place, Promotion, People, Physical Evidence and Process) were
commonly used by these hotels, however, three types – People, Price
and Physical Evidence were considered most important by the
owners.