Abstract: Water flow management is one of the most important
parts of river engineering. Non-uniformity distribution of rainfall and
various flow demand with unreasonable flow management will be
caused destroyed of river ecosystem. Then, it is very serious to
determine ecosystem flow requirement. In this paper, Flow duration
curve indices method which has hydrological based was used to
evaluate environmental flow in Gharasou River, Ardabil, Iran. Using
flow duration curve, Q90 and Q95 for different return periods were
calculated. Their magnitude were determined as 1-day, 3-day, 7-day
and 30 day. According the second method, hydraulic alteration
indices often had low and medium range. In order to maintain river at
an acceptable ecological condition, minimum daily discharge of
index Q95 is 0.7 m3.s-1.
Abstract: In this paper a real-time obstacle avoidance approach
for both autonomous and non-autonomous dynamical systems (DS) is
presented. In this approach the original dynamics of the controller
which allow us to determine safety margin can be modulated.
Different common types of DS increase the robot’s reactiveness in
the face of uncertainty in the localization of the obstacle especially
when robot moves very fast in changeable complex environments.
The method is validated by simulation and influence of different
autonomous and non-autonomous DS such as important
characteristics of limit cycles and unstable DS. Furthermore, the
position of different obstacles in complex environment is explained.
Finally, the verification of avoidance trajectories is described through
different parameters such as safety factor.
Abstract: An environmentally benign protocol for the one-pot,
three-component synthesis of Triazolo[1,2-a]indazole-1,3,8-trione
derivatives by condensation of dimedone, urazole and aromatic
aldehydes catalyzed by HClO4/SiO2 NPS as an ecofriendly catalyst
with high catalytic activity and reusability at 100ºC under solventfree
conditions is reported. The reaction proceeds to completion
within 20-30 min in 77-86% yield.
Abstract: Food is widely packaged with plastic materials to
prevent microbial contamination and spoilage. Ionizing radiation is
widely used to sterilize the food-packaging materials. Sterilization by
γ-radiation causes degradation such as embrittlement, stiffening,
softening, discoloration, odour generation, and decrease in molecular
weight. Many antioxidants can prevent γ-degradation but most of
them are toxic. The migration of antioxidants to its environment
gives rise to major concerns in case of food packaging plastics. In
this attempt, we have aimed to utilize synergistic mixtures of
stabilizers which are approved for food-contact applications.
Ethylene-propylene-diene terpolymer has been melt-mixed with
hindered amine stabilizers (HAS), phenolic antioxidants and organophosphites
(hydroperoxide decomposer). Results were discussed by
comparing the stabilizing efficiency of mixtures with and without
phenol system. Among phenol containing systems where we mostly
observed discoloration due to the oxidation of hindered phenol, the
combination of secondary HAS, tertiary HAS, organo-phosphite and
hindered phenol exhibited improved stabilization efficiency than
single or binary additive systems. The mixture of secondary HAS and
tertiary HAS, has shown antagonistic effect of stabilization.
However, the combination of organo-phosphite with secondary HAS,
tertiary HAS and phenol antioxidants have been found to give
synergistic even at higher doses of Gamma-irradiation. The effects
have been explained through the interaction between the stabilizers.
After γ-irradiation, the consumption of oligomeric stabilizer
significantly depends on the components of stabilization mixture. The
effect of the organo-phosphite antioxidant on the overall stability has
been discussed.
Abstract: This study presents synthesis of novel block
copolymers of thienyl end capped ethoxylated nonyl phenol and
pyrrole via chemical oxidative polymerization. Ethoxylated nonyl
phenol (ENP) was reacted with 2-thiophenecarbonyl chloride in order
to synthesize a macromonomer containing thienyl end-group (ENPThC).
Then copolymers of ENP-ThC and pyrrole were synthesized
by chemical oxidative polymerization using iron (III) chloride as an
oxidant. ENP-ThC served both as a macromonomer and an emulsifier
for pyrrole with poor solubility in water.
The synthesized block copolymers (ENP-ThC-b-PPy) were
characterized by spectroscopic analysis and the electrical
conductivities were investigated with 4-point probe technique.
Abstract: Lightweight design represents an important key to
successful implementation of energy-saving, fuel-efficient and
environmentally friendly means of transport in the aerospace and
automotive industry. In this context the use of carbon fibre reinforced
plastics (CFRP) which are distinguished by their outstanding
mechanical properties at relatively low weight, promise significant
improvements. Due to the reduction of the total mass, with the
resulting lowered fuel or energy consumption and CO2 emissions
during the operational phase, commercial aircraft will increasingly be
made of CFRP. An auspicious technology for the efficient and
economic production of high performance thermoset composites and
hybrid structures for future lightweight applications is the
combination of carbon fibre sheet moulding compound, tailored
continuous carbon fibre reinforcements and metallic components in a
one-shot pressing and curing process. This paper deals with a hybrid
composite technology for aerospace industries, which was developed
with the help of a special innovation and development system.
Abstract: Vertical Handover(VHO) among different
communication technologies ensuring uninterruption and service
continuity is one of the most important performance parameter in
Heterogenous networks environment. In an integrated Universal
Mobile Telecommunicatin System(UMTS) and Wireless Local
Area Network(WLAN), WLAN is given an inherent priority over
UMTS because of its high data rates with low cost. Therefore
mobile users want to be associated with WLAN maximum of the
time while roaming, to enjoy best possible services with low cost.
That encourages reduction of number of VHO. In this work the
reduction of number of VHO with respect to varying number of
WLAN Access Points(APs) in an integrated UMTS and WLAN
network is investigated through simulation to provide best possible
cost effective service to the users. The simulation has been carried
out for an area (7800 × 9006)m2 where COST-231 Hata model
and 3GPP (TR 101 112 V 3.1.0) specified models are used for
WLAN and UMTS path loss models respectively. The handover
decision is triggered based on the received signal level as compared
to the fade margin. Fade margin gives a probabilistic measure of
the reliability of the communication link. A relationship between
number of WLAN APs and the number of VHO is also established
in this work.
Abstract: The final energy use can be divided mainly in four sectors: commercial, industrial, residential, and transportation. The trend in final energy consumption by sector plays as a most straightforward way to provide a wide indication of progress for reducing energy consumption and associated environmental impacts by different end use sectors. The average share of end use energy for residential sector in the world was nearly 20% until 2011, in Germany a higher proportion is between 25% and 30%. However, it remains less studied than energy use in other three sectors as well its impacts on climate and environment. The reason for this involves a wide range of fields, including the diversity of residential construction like different housing building design and materials, living or energy using behavioral patterns, climatic condition and variation as well other social obstacles, market trend potential and financial support from government.
This paper presents an extensive and in-depth analysis of the manner by which projects researched and operated by authors in the fields of energy efficiency primarily from the perspectives of both technical potential and initiative energy saving consciousness in the residential sectors especially in social housing buildings.
Abstract: In this study, data loss tolerance of Support Vector Machines (SVM) based activity recognition model and multi activity classification performance when data are received over a lossy wireless sensor network is examined. Initially, the classification algorithm we use is evaluated in terms of resilience to random data loss with 3D acceleration sensor data for sitting, lying, walking and standing actions. The results show that the proposed classification method can recognize these activities successfully despite high data loss. Secondly, the effect of differentiated quality of service performance on activity recognition success is measured with activity data acquired from a multi hop wireless sensor network, which introduces high data loss. The effect of number of nodes on the reliability and multi activity classification success is demonstrated in simulation environment. To the best of our knowledge, the effect of data loss in a wireless sensor network on activity detection success rate of an SVM based classification algorithm has not been studied before.
Abstract: Cloud computing (CC) has already gained overall
appreciation in research and practice. Whereas the willingness to
integrate cloud services in various IT environments is still unbroken,
the previous CC procurement processes run mostly in an unorganized
and non-standardized way. In practice, a sufficiently specific, yet
applicable business process for the important acquisition phase is
often lacking. And research does not appropriately remedy this
deficiency yet. Therefore, this paper introduces a field-tested
approach for CC procurement. Based on an extensive literature
review and augmented by expert interviews, we designed a model
that is validated and further refined through an in-depth real-life case
study. For the detailed process description, we apply the event-driven
process chain notation (EPC). The gained valuable insights into the
case study may help CC research to shift to a more socio-technical
area. For practice, next to giving useful organizational instructions
we will provide extended checklists and lessons learned.
Abstract: Replacement of plastics used in the food industry
seems to be a serious issue to overcome mainly the environmental
problems in recent years. This study investigates the hydrophilicity
and permeability properties of starch biopolymer which ethylene
vinyl alcohol (EVOH) (0-10%) and nanocrystalline cellulose (NCC)
(1-15%) were used to enhance its properties. Starch -EVOH
nanocomposites were prepared by casting method in different
formulations. NCC production by acid hydrolysis was confirmed by
scanning electron microscopy. Solubility, water vapor permeability,
water vapor transmission rate and moisture absorbance were
measured on each of the nanocomposites. The results were analyzed
by SAS software. The lowest moisture absorbance was measured in
pure starch nanocomposite containing 8% NCC. The lowest
permeability to water vapor belongs to starch nanocomposite
containing 8% NCC and the sample containing 7.8% EVOH and 13%
NCC. Also the lowest solubility was observed in the composite
contains the highest amount of EVOH. Applied Process resulted in
production of bio films which have good resistance to water vapor
permeability and solubility in water. The use of NCC and EVOH
leads to reduced moisture absorbance property of the biofilms.
Abstract: Locating Radio Controlled (RC) devices using their
unintended emissions has a great interest considering security
concerns. Weak nature of these emissions requires near field
localization approach since it is hard to detect these signals in far
field region of array. Instead of only angle estimation, near field
localization also requires range estimation of the source which makes
this method more complicated than far field models. Challenges of
locating such devices in a near field region and real time environment
are analyzed in this paper. An ESPRIT like near field localization
scheme is utilized for both angle and range estimation. 1-D search
with symmetric subarrays is provided. Two 7 element uniform linear
antenna arrays (ULA) are employed for locating RC source.
Experiment results of location estimation for one unintended emitting
walkie-talkie for different positions are given.
Abstract: In this study, we propose a novel technique for acoustic
echo suppression (AES) during speech recognition under barge-in
conditions. Conventional AES methods based on spectral subtraction
apply fixed weights to the estimated echo path transfer function
(EPTF) at the current signal segment and to the EPTF estimated until
the previous time interval. However, the effects of echo path changes
should be considered for eliminating the undesired echoes. We
describe a new approach that adaptively updates weight parameters in
response to abrupt changes in the acoustic environment due to
background noises or double-talk. Furthermore, we devised a voice
activity detector and an initial time-delay estimator for barge-in speech
recognition in communication networks. The initial time delay is
estimated using log-spectral distance measure, as well as
cross-correlation coefficients. The experimental results show that the
developed techniques can be successfully applied in barge-in speech
recognition systems.
Abstract: Food as perishable goods represents a specific and
sensitive part in the supply chain theory, since changing physical or
chemical characteristics considerably influence the approach to stock
management. The most delicate phase of this process is
transportation, where it becomes difficult to ensure the stable
conditions which limit deterioration, since the value of the
deterioration rate could be easily influenced by the mode of
transportation. The fuzzy definition of variables allows one to take
these variations into account. Furthermore, an appropriate choice of
the defuzzification method permits one to adapt results to real
conditions as far as possible. In this article those methods which take
into account the relationship between the deterioration rate of
perishable goods and transportation by ship will be applied with the
aim of (a) minimizing the total cost function, defined as the sum of
the ordering cost, holding cost, disposing cost and transportation
costs, and (b) improving the supply chain sustainability by reducing
environmental impact and waste disposal costs.
Abstract: In this study, the performance analyses of the twenty
five Coal-Fired Power Plants (CFPPs) used for electricity generation
are carried out through various Data Envelopment Analysis (DEA)
models. Three efficiency indices are defined and pursued. During the
calculation of the operational performance, energy and non-energy
variables are used as input, and net electricity produced is used as
desired output (Model-1). CO2 emitted to the environment is used as
the undesired output (Model-2) in the computation of the pure
environmental performance while in Model-3 CO2 emissions is
considered as detrimental input in the calculation of operational and
environmental performance. Empirical results show that most of the
plants are operating in increasing returns to scale region and Mettur
plant is efficient one with regards to energy use and environment.
The result also indicates that the undesirable output effect is
insignificant in the research sample. The present study will provide
clues to plant operators towards raising the operational and
environmental performance of CFPPs.
Abstract: Environmental impacts of six 3D printers using
various materials were compared to determine if material choice
drove sustainability, or if other factors such as machine type, machine
size, or machine utilization dominate. Cradle-to-grave life-cycle
assessments were performed, comparing a commercial-scale FDM
machine printing in ABS plastic, a desktop FDM machine printing in
ABS, a desktop FDM machine printing in PET and PLA plastics, a
polyjet machine printing in its proprietary polymer, an SLA machine
printing in its polymer, and an inkjet machine hacked to print in salt
and dextrose. All scenarios were scored using ReCiPe Endpoint H
methodology to combine multiple impact categories, comparing
environmental impacts per part made for several scenarios per
machine. Results showed that most printers’ ecological impacts were
dominated by electricity use, not materials, and the changes in
electricity use due to different plastics was not significant compared
to variation from one machine to another. Variation in machine idle
time determined impacts per part most strongly. However, material
impacts were quite important for the inkjet printer hacked to print in
salt: In its optimal scenario, it had up to 1/38th the impacts coreper
part as the worst-performing machine in the same scenario. If salt
parts were infused with epoxy to make them more physically robust,
then much of this advantage disappeared, and material impacts
actually dominated or equaled electricity use. Future studies should
also measure DMLS and SLS processes / materials.
Abstract: Passing the entrance exam to a university is a major
step in one's life. University entrance exam commonly known as
Kankor is the nationwide entrance exam in Afghanistan. This
examination is prerequisite for all public and private higher education
institutions at undergraduate level. It is usually taken by students who
are graduated from high schools. In this paper, we reflect the major
educational school graduates issues and propose ICT-based test
preparation environment, known as ‘Online Kankor Exam Prep
System’ to give students the tools to help them pass the university
entrance exam on the first try. The system is based on Intelligent
Tutoring System (ITS), which introduced an essential package of
educational technology for learners that features: (I) exam-focused
questions and content; (ii) self-assessment environment; and (iii) test
preparation strategies in order to help students to acquire the necessary
skills in their carrier and keep them up-to-date with instruction.
Abstract: Particles exhausted from cars have adverse impacts on
human health. The study developed a three-dimensional particle
dispersion numerical model including particle coagulation to simulate
the particle concentration distribution under idling conditions in a
residential underground garage. The simulation results demonstrate
that particle disperses much faster in the vertical direction than that in
horizontal direction. The enhancement of particle dispersion in the
vertical direction due to the increase of cars with engine running is
much stronger than that in the car exhaust direction. Particle dispersion
from each pair of adjacent cars has little influence on each other in the
study. Average particle concentration after 120 seconds exhaust is
1.8-4.5 times higher than the initial total particles at ambient
environment. Particle pollution in the residential underground garage
is severe.
Abstract: Factors affecting construction unit cost vary
depending on a country’s political, economic, social and
technological inclinations. Factors affecting construction costs have
been studied from various perspectives. Analysis of cost factors
requires an appreciation of a country’s practices. Identified cost
factors provide an indication of a country’s construction economic
strata. The purpose of this paper is to identify the essential factors
that affect unit cost estimation and their breakdown using artificial
neural networks. Twenty five (25) identified cost factors in road
construction were subjected to a questionnaire survey and employing
SPSS factor analysis the factors were reduced to eight. The 8 factors
were analysed using neural network (NN) to determine the
proportionate breakdown of the cost factors in a given construction
unit rate. NN predicted that political environment accounted 44% of
the unit rate followed by contractor capacity at 22% and financial
delays, project feasibility and overhead & profit each at 11%. Project
location, material availability and corruption perception index had
minimal impact on the unit cost from the training data provided.
Quantified cost factors can be incorporated in unit cost estimation
models (UCEM) to produce more accurate estimates. This can create
improvements in the cost estimation of infrastructure projects and
establish a benchmark standard to assist the process of alignment of
work practises and training of new staff, permitting the on-going
development of best practises in cost estimation to become more
effective.
Abstract: Climate change confronts the built environment with
many new challenges in the form of more severe and frequent hydrometeorological
events. A series of strategies is proposed whereby the
various aspects of buildings and their sites can be made more resilient
to the effects of such events.