Abstract: Today Environmental Impact Assessment (EIA) is known as one of the most important tools for decision makers in the construction of civil and industrial projects towards sustainable development. In the past, projects were evaluated based on cost and benefit analysis regardless of the physical and biological environmental effects and its socio-economical impacts. According to the Department of Environment (DOE) of Iran's regulations, the construction of hydroelectric dams is an activity that requires an EIA report. In this paper the environmental impact assessment of the Gotvand hydro-electrical dam has been evaluated in the three environment elements, biological, Physical-chemical and cultural units. This dam is one of the largest dams in Iran with a volume of 4500 MCM and is going to be the last dam on the Karoon River in the south of Iran. In this paper the ICOLD (International Commission on Large Dams) technique was employed for the environmental impact assessment of the dam. The research includes all socio economical and environmental effects of the dam during the construction and operation of the hydro electric dam and Environmental management, monitoring and mitigation of negative impacts were analyzed. In this project the results led to using some techniques to protect the destructive impacts on biological aspects beside the effective long time period impacts on the biological aspects. The impacts on physical aspects are temporary and negative commonly that could be restored and rehabilitated in natural process in the long time in operation period.
Abstract: An inverse geometry problem is solved to predict an
unknown irregular boundary profile. The aim is to minimize the
objective function, which is the difference between real and
computed temperatures, using three different versions of Conjugate
Gradient Method. The gradient of the objective function, considered
necessary in this method, obtained as a result of solving the adjoint
equation. The abilities of three versions of Conjugate Gradient
Method in predicting the boundary profile are compared using a
numerical algorithm based on the method. The predicted shapes show
that due to its convergence rate and accuracy of predicted values, the
Powell-Beale version of the method is more effective than the
Fletcher-Reeves and Polak –Ribiere versions.
Abstract: The main objective of this research is to synthesize silk fibroin fiber for indoor air particulate removal. Silk cocoons were de-gummed using 0.5 wt % Na2CO3 alkaline solutions at 90 Ó╣ìC for 60 mins, washed with distilled water, and dried at 80 Ó╣ìC for 3 hrs in a vacuum oven. Two sets of experiment were conducted to investigate the impacts of initial particulate matter (PM) concentration and that of air flow rate on the removal efficiency. Rice bran collected from a local rice mill in Ubonratchathani province was used as indoor air contaminant in this work. The morphology and physical properties of silk fibroin (SF) fiber were measured. The SEM revealed the deposition of PM on the used fiber. The PM removal efficiencies of 72.29 ± 3.03 % and 39.33 ± 1.99 % were obtained of PM10 and PM2.5, respectively, when using the initial PM concentration at 0.040 mg/m3 and 0.020 mg/m3 of PM10 and PM2.5, respectively, with the air flow rate of 5 L/min.
Abstract: This paper presents the results related to the
interference reduction technique in multistage multiuser detector for
asynchronous DS-CDMA system. To meet the real-time
requirements for asynchronous multiuser detection, a bit streaming,
cascade architecture is used. An asynchronous multiuser detection
involves block-based computations and matrix inversions. The paper
covers iterative-based suboptimal schemes that have been studied to
decrease the computational complexity, eliminate the need for matrix
inversions, decreases the execution time, reduces the memory
requirements and uses joint estimation and detection process that
gives better performance than the independent parameter estimation
method. The stages of the iteration use cascaded and bits processed
in a streaming fashion. The simulation has been carried out for
asynchronous DS-CDMA system by varying one parameter, i.e.,
number of users. The simulation result exhibits that system gives
optimum bit error rate (BER) at 3rd stage for 15-users.
Abstract: In this paper, two versions of an iterative loopless
algorithm for the classical towers of Hanoi problem with O(1) storage complexity and O(2n) time complexity are presented. Based
on this algorithm the number of different moves in each of pegs with its direction is formulated.
Abstract: One promising way to achieve low temperature
combustion regime is the use of a large amount of cooled EGR. In
this paper, the effect of injection timing on low temperature
combustion process and emissions were investigated via three
dimensional computational fluid dynamics (CFD) procedures in a DI
diesel engine using high EGR rates. The results show when
increasing EGR from low levels to levels corresponding to reduced
temperature combustion, soot emission after first increasing, is
decreased beyond 40% EGR and get the lowest value at 58% EGR
rate. Soot and NOx emissions are simultaneously decreased at
advanced injection timing before 20.5 ºCA BTDC in conjunction
with 58% cooled EGR rate in compared to baseline case.
Abstract: the elastic scattering of protons, deuterons and 3He on 6Li at different incident energies have been analyzed in the framework of the optical model using ECIS88 as well as SPI GENOA codes. The potential parameters were extracted in the phenomenological treatment of measured by us angular distributions and literature data. A good agreement between theoretical and experimental differential cross sections was obtained in whole angular range. Parameters for real part of potential have been also calculated microscopically with singleand double-folding model for the p and d, 3He scattering, respectively, using DFPOT code. For best agreement with experiment the normalization factor N for the potential depth is obtained in the range of 0.7-0.9.
Abstract: Tourism researchers have recently focused on repeat visitation as a part of destination loyalty. Different models have also considered satisfaction as the main determinant of revisit intention, while findings in many studies show it as a continuous issue. This conceptual paper attempts at evaluating recent empirical studies on satisfaction and revisit intention. Based on limitations and gaps in recent studies, the current paper suggests a new model that would be more comprehensive than those in previous studies. The new model offers new relationships between antecedents (destination image, perceived value, specific novelty seeking, and distance to destination) and both of satisfaction and revisit intention. Revisit intention in turn is suggested to be measured in a temporal approach.
Abstract: In this paper, we propose an efficient hierarchical DNA
sequence search method to improve the search speed while the
accuracy is being kept constant. For a given query DNA sequence,
firstly, a fast local search method using histogram features is used as a
filtering mechanism before scanning the sequences in the database.
An overlapping processing is newly added to improve the robustness
of the algorithm. A large number of DNA sequences with low
similarity will be excluded for latter searching. The Smith-Waterman
algorithm is then applied to each remainder sequences. Experimental
results using GenBank sequence data show the proposed method
combining histogram information and Smith-Waterman algorithm is
more efficient for DNA sequence search.
Abstract: Vehicular communications play a substantial role in providing safety in transportation by means of safety message exchange. Researchers have proposed several solutions for securing safety messages. Protocols based on a fixed key infrastructure are more efficient in implementation and maintain stronger security in comparison with dynamic structures. These protocols utilize zone partitioning to establish distinct key infrastructure under Certificate Authority (CA) supervision in different regions. Secure anonymous broadcasting (SAB) is one of these protocols that preserves most of security aspects but it has some deficiencies in practice. A very important issue is region change of a vehicle for its mobility. Changing regions leads to change of CA and necessity of having new key set to resume communication. In this paper, we propose solutions for informing vehicles about region change to obtain new key set before entering next region. This hinders attackers- intrusion, packet loss and lessons time delay. We also make key request messages secure by confirming old CA-s public key to the message, hence stronger security for safety message broadcasting is attained.
Abstract: Density functional theory (DFT) calculations were performed to calculate aluminum-27, boron-11, and nitrogen-14 quadrupole coupling constant (CQ) in the representative considered model of (6, 0) boron nitride-aluminum nitride nanotube junction (BN-AlNNT) for the first time. To this aim, 1.3 nm length of BNAlN consisting of 18 Al, 18 B, and 36 N atoms was selected where the end atoms capped by hydrogen atoms. The calculated CQ values for optimized BN-AlNNT system reveal different electrostatic environment in the mentioned system. The calculations were performed using the Gaussian 98 package of program.
Abstract: Biplot can be used to evaluate cultivars for their oil
percent potential and stability and to evaluate trial sites for their
discriminating ability and representativeness. Multi-environmental
trial (MET) data for oil percent of 10 open pollinating sunflower
cultivars were analyzed to investigate the genotype-environment
interactions. The genotypes were evaluated in four locations with
different climatic conditions in Iran in 2010. In each location, a
Randomized Complete Block design with four replications was used.
According to both mean and stability, Zaria, Master and R453, had
highest performances among all cultivars. The graphical analysis
identified best cultivar for each environment. Cultivars Berezans and
Record performed best in Khoy and Islamabad. Zaria and R453 were
the best genotypes in Sari and Karaj followed by Master and Favorit.
The GGE bi-plot indicated two mega-environments, group one
contained Karaj, Khoy and Islamabad and the second group
contained Sari. The best discriminating location was Karaj followed
with Khoy, Islamabad and Sari. The best representative genotypes
were Zaria, R453, Master and Favorit. Ranking of ten cultivars based
their oil percent was as Zaria > R453 ≈ Master ≈ Favorit > Record ≈
Berezans > Sor > Lakumka > Bulg3 > Bulg5.
Abstract: In recent years, strategic alliances have taken
increasing importance as a means to control competitive forces and to
enter into new markets. Joint ventures are one of the most frequently
used contractual forms in strategic alliances. There are various
motivations for cooperation between two or more firms e.g.,
accessing to technical know-how, accessing to financial resources
and managing risks. The firms must know about these motivations to
encourage for establishing joint venture. So, it is important for
managers to understand about these motives. On the other hand, the
cooperation section is one of the most effective parts in each country.
In this way, our study identifies goals of joint venture between
cooperative manufacturing firms, and prioritizes those using
TOPSIS1. The results show that the most important of joint venture
goals are: accessing to managerial know-how, sharing total capital
investment.
Abstract: The study was designed to evaluate the use of low
concentrations of separan flocculent (Less than 3 ppm) on
physicochemical properties of sugar cane juice. Colour, pH, purity,
turbidity, pol, brix, reducing sugars tannins and polyphenols of
crushed cane (green and burned) juice, mixed juice and clarified
juice were studied. The results showed that pol, brix, reducing sugar
and turbidity are higher in crushed cane juice. Clarified burned juice
had low turbidity, reducing sugars, pol and brix but had significantly
lower pH, purity and colour when compared to crushed juice.
Polyphenols of the crushed juice (1.19%) decreased significantly in
the clarified juice to 0.006%. Addition of separan at a concentration
of 0.015 ppm reduced significantly colour, polyphenols and tannins
and reducing sugar compared to the control.
Abstract: In this paper, we establish existence and uniqueness of
solutions for a class of inverse problems of degenerate differential
equations. The main tool is the perturbation theory for linear operators.
Abstract: Selecting the word translation from a set of target
language words, one that conveys the correct sense of source word
and makes more fluent target language output, is one of core
problems in machine translation. In this paper we compare the 3
methods of estimating word translation probabilities for selecting the
translation word in Thai – English Machine Translation. The 3
methods are (1) Method based on frequency of word translation, (2)
Method based on collocation of word translation, and (3) Method
based on Expectation Maximization (EM) algorithm. For evaluation
we used Thai – English parallel sentences generated by NECTEC.
The method based on EM algorithm is the best method in comparison
to the other methods and gives the satisfying results.
Abstract: The current paper presents the findings of a research
study on learners- barriers and motivators engaged into blended
programs in a workplace context. In this study, the participants were
randomly assigned to one of four parallel e-learning courses, each of
which was delivered using a different learning strategy. Data were
collected through web-based and telephone surveys developed by the
researchers. The results showed that vague instruction, time
management, and insufficient feedback were the top-most barriers to
blended learning. The major motivators for blended learning included
content relevance, flexibility in time, and the ability to work at own
pace.
Abstract: Today, incorrect use of lands and land use changes,
excessive grazing, no suitable using of agricultural farms, plowing on
steep slopes, road construct, building construct, mine excavation etc
have been caused increasing of soil erosion and sediment yield. For
erosion and sediment estimation one can use statistical and empirical
methods. This needs to identify land unit map and the map of
effective factors. However, these empirical methods are usually time
consuming and do not give accurate estimation of erosion. In this
study, we applied GIS techniques to estimate erosion and sediment of
Menderjan watershed at upstream Zayandehrud river in center of
Iran. Erosion faces at each land unit were defined on the basis of land
use, geology and land unit map using GIS. The UTM coordinates of
each erosion type that showed more erosion amounts such as rills and
gullies were inserted in GIS using GPS data. The frequency of
erosion indicators at each land unit, land use and their sediment yield
of these indices were calculated. Also using tendency analysis of
sediment yield changes in watershed outlet (Menderjan hydrometric
gauge station), was calculated related parameters and estimation
errors. The results of this study according to implemented watershed
management projects can be used for more rapid and more accurate
estimation of erosion than traditional methods. These results can also
be used for regional erosion assessment and can be used for remote
sensing image processing.
Abstract: Performance of a dual maximal ratio combining
receiver has been analyzed for M-ary coherent and non-coherent
modulations over correlated Nakagami-m fading channels with nonidentical
and arbitrary fading parameter. The classical probability
density function (PDF) based approach is used for analysis.
Expressions for outage probability and average symbol error
performance for M-ary coherent and non-coherent modulations have
been obtained. The obtained results are verified against the special
case published results and found to be matching. The effect of the
unequal fading parameters, branch correlation and unequal input
average SNR on the receiver performance has been studied.
Abstract: The corrugated steel cladding used to cover most of
steel buildings is considered as non-structural element. This research
will reflect the effect of cladding as a shear diaphragm in increasing
the normal elastic capacity of columns. This study is important
because of the lack of information of the behavior of cladding and
secondary members in various codes. Mathematical models for six
different cases are carried by software. The results extracted from the
program have been plotted showing the effects of different variables
on the ultimate load of column. The variables considered in our
research are the spacing between columns and the thickness of the
corrugated sheet representing the sheet stiffness.