Abstract: The National Bridge Inventory (NBI) includes more
than 600,000 bridges within the United States of America.
Prestressed concrete girder bridges represent one of the most widely
used bridge systems. The majority of these girder bridges were
constructed using 0.5 and 0.6 inch diameter strands. The main
impediments to using larger strand diameters are: 1) lack of prestress
bed capacities, 2) lack of structural knowledge regarding the transfer
and development length of larger strands, and 3) the possibility of
developing wider end zone cracks upon strand release.
This paper presents a study about using 0.7 inch strands in girder
fabrication. Transfer and development length were evaluated, and
girders were fabricated using 0.7 inch strands at different spacings.
Results showed that 0.7 inch strands can be used at 2.0 inch spacing
without violating the AASHTO LRFD Specifications, while attaining
superior performance in shear and flexure.
Abstract: Enzymatic hydrolysis of starch from natural sources
finds potential application in commercial production of alcoholic
beverage and bioethanol. In this study the effect of starch
concentration, temperature, time and enzyme concentration were
studied and optimized for hydrolysis of cassava (Manihot esculenta)
starch powder (of mesh 80/120) into glucose syrup by immobilized
(using Polyacrylamide gel) a-amylase using central composite
design. The experimental result on enzymatic hydrolysis of cassava
starch was subjected to multiple linear regression analysis using
MINITAB 14 software. Positive linear effect of starch concentration,
enzyme concentration and time was observed on hydrolysis of
cassava starch by a-amylase. The statistical significance of the model
was validated by F-test for analysis of variance (p < 0.01). The
optimum value of starch concentration temperature, time and enzyme
concentration were found to be 4.5% (w/v), 45oC, 150 min, and 1%
(w/v) enzyme. The maximum glucose yield at optimum condition
was 5.17 mg/mL.
Abstract: Several valve stiction models have been proposed in the literature to help understand and study the behavior of sticky valves. In this paper, an alternative black-box modeling approach based on Neural Network (NN) is presented. It is shown that with proper network type and optimum model structures, the performance of the developed NN stiction model is comparable to other established method. The resulting NN model is also tested for its robustness against the uncertainty in the stiction parameter values. Predictive mode operation also shows excellent performance of the proposed model for multi-steps ahead prediction.
Abstract: This paper presents a portable robot that is to use for
welding process in shipbuilding yard. It has six degree of freedom and
3kg payload capability. Its weight is 21.5kg so that human workers can
carry it to the work place. Its body mainly made of magnesium alloy
and aluminum alloy for few parts that require high strength. Since the
distance between robot and controller should be 50m at most, the robot
controller controls the robot through EtherCAT. RTX and KPA are
used for real time EtherCAT control on Windows XP. The
performance of the developed robot was satisfactory, in welding of U
type cell in shipbuilding yard.
Abstract: The development of many measurement and inspection systems of products based on real-time image processing can not be carried out totally in a laboratory due to the size or the temperature of the manufactured products. Those systems must be developed in successive phases. Firstly, the system is installed in the production line with only an operational service to acquire images of the products and other complementary signals. Next, a recording service of the image and signals must be developed and integrated in the system. Only after a large set of images of products is available, the development of the real-time image processing algorithms for measurement or inspection of the products can be accomplished under realistic conditions. Finally, the recording service is turned off or eliminated and the system operates only with the real-time services for the acquisition and processing of the images. This article presents a systematic performance evaluation of the image compression algorithms currently available to implement a real-time recording service. The results allow establishing a trade off between the reduction or compression of the image size and the CPU time required to get that compression level.
Abstract: Buildings are considered as significant part in the
cities, which plays main role in organization and arrangement of city
appearance, which is affects image of that building facades, as an
connective between inner and outer space, have a main role in city
image and they are classified as rich image and poor image by people
evaluation which related to visual architectural and urban elements in
building facades. the buildings in Karimi street , in Lahijan city
where, lies in north of Iran, contain the variety of building's facade
types which, have made a city image in Historical part of Lahijan
city, while reflected the Iranian cities identity. The study attempt to
identify the architectural and urban elements that impression the
image of building facades in historical area, based on public
evaluation. Quantitative method were used and the data was collected
through questionnaire survey, the result presented architectural style,
color, shape, and design evaluated by people as most important factor
which should be understate in future development. in fact, the rich
architectural style with strong design make strong city image as weak
design make poor city image.
Abstract: in dissimilar material joints, failure often occurs
along the interface between two materials due to stress singularity.
Stress distribution and its concentration depend on materials and
geometry of the junction. Inhomogenity of stress distribution at the
interface of junction of two materials with different elastic modules
and stress concentration in this zone are the main factors resulting in
rupture of the junction. Effect of joining angle in the interface of
aluminum-polycarbonate will be discussed in this paper. Computer
simulation and finite element analysis by ABAQUS showed that
convex interfacial joint leads to stress reduction at junction corners in
compare with straight joint. This finding is confirmed by photoelastic
experimental results.
Abstract: Human computer interaction has progressed
considerably from the traditional modes of interaction. Vision based
interfaces are a revolutionary technology, allowing interaction
through human actions, gestures. Researchers have developed
numerous accurate techniques, however, with an exception to few
these techniques are not evaluated using standard HCI techniques. In
this paper we present a comprehensive framework to address this
issue. Our evaluation of a computer vision application shows that in
addition to the accuracy, it is vital to address human factors
Abstract: Capacitive electrocardiogram (ECG) measurement is an attractive approach for long-term health monitoring. However, there is little literature available on its implementation, especially for multichannel system in standard ECG leads. This paper begins from the design criteria for capacitive ECG measurement and presents a multichannel limb-lead capacitive ECG system with conductive fabric tapes pasted on a double layer PCB as the capacitive sensors. The proposed prototype system incorporates a capacitive driven-body (CDB) circuit to reduce the common-mode power-line interference (PLI). The presented prototype system has been verified to be stable by theoretic analysis and practical long-term experiments. The signal quality is competitive to that acquired by commercial ECG machines. The feasible size and distance of capacitive sensor have also been evaluated by a series of tests. From the test results, it is suggested to be greater than 60 cm2 in sensor size and be smaller than 1.5 mm in distance for capacitive ECG measurement.
Abstract: Direction of Arrival estimation refers to defining a mathematical function called a pseudospectrum that gives an indication of the angle a signal is impinging on the antenna array. This estimation is an efficient method of improving the quality of service in a communication system by focusing the reception and transmission only in the estimated direction thereby increasing fidelity with a provision to suppress interferers. This improvement is largely dependent on the performance of the algorithm employed in the estimation. Many DOA algorithms exists amongst which are MUSIC, Root-MUSIC and ESPRIT. In this paper, performance of these three algorithms is analyzed in terms of complexity, accuracy as assessed and characterized by the CRLB and memory requirements in various environments and array sizes. It is found that the three algorithms are high resolution and dependent on the operating environment and the array size.
Abstract: The nexus between language and culture is so
intertwined and very significant that language is largely seen as a
vehicle for cultural transmission. Culture itself refers to the aggregate
belief system of a people, embellishing its corporate national image
or brand. If we conceive national rebranding as a campaign to
rekindle the patriotic flame in the consciousness of a people towards
its sociocultural imperatives and values, then, Nigerian indigenous
linguistic flame has not been ignited. Consequently, the paper
contends that the current national rebranding policy remains a myth
in the confines of the elitists' intellectual squabble. It however
recommends that the use of our indigenous languages should be
supported by adequate legislation and also propagated by Nollywood
in order to revamp and sustain the people’s interest in their local
languages. Finally, the use of the indigenous Nigerian languages
demonstrates patriotism, an important ingredient for actualizing a
genuine national rebranding.
Abstract: This article presents the results of researchrelated to the assessment protocol weightedcumulative expected transmission time (WCETT)applied to cognitive radio networks.The development work was based on researchdone by different authors, we simulated a network,which communicates wirelessly, using a licensedchannel, through which other nodes are notlicensed, try to transmit during a given time nodeuntil the station's owner begins its transmission.
Abstract: Qualification of doctoral students- and the candidates for a scientific degree is evaluated by the ability to solve scientific ideas in an innovative way, consequently, being a potential of research and science they play a significant role in the sustainability context of the society. The article deals with the analysis of the results of the pilot project, the aim of which has been to study the structure of doctoral students- research competences in the sustainability context. With the existance of variety of theories on research competence development, their analysis focuses on the attained aim approach. Three competence groups have been identified in this study: informative, communicative and instrumental. Within the study the doctoral students and candidates for a scientific degree (N=64) made their self-assessment of research competences. The study results depict their present research competence development level and its dynamics according to the aim to attain.
Abstract: Multiple sequence alignment is a fundamental part in
many bioinformatics applications such as phylogenetic analysis.
Many alignment methods have been proposed. Each method gives a
different result for the same data set, and consequently generates a
different phylogenetic tree. Hence, the chosen alignment method
affects the resulting tree. However in the literature, there is no
evaluation of multiple alignment methods based on the comparison of
their phylogenetic trees. This work evaluates the following eight
aligners: ClustalX, T-Coffee, SAGA, MUSCLE, MAFFT, DIALIGN,
ProbCons and Align-m, based on their phylogenetic trees (test trees)
produced on a given data set. The Neighbor-Joining method is used
to estimate trees. Three criteria, namely, the dNNI, the dRF and the
Id_Tree are established to test the ability of different alignment
methods to produce closer test tree compared to the reference one
(true tree). Results show that the method which produces the most
accurate alignment gives the nearest test tree to the reference tree.
MUSCLE outperforms all aligners with respect to the three criteria
and for all datasets, performing particularly better when sequence
identities are within 10-20%. It is followed by T-Coffee at lower
sequence identity (30%), trees scores of all methods
become similar.
Abstract: The notion of S-fuzzy left h-ideals in a hemiring is introduced and it's basic properties are investigated.We also study the homomorphic image and preimage of S-fuzzy left h-ideal of hemirings.Using a collection of left h-ideals of a hemiring, S-fuzzy left h-ideal of hemirings are established.The notion of a finite-valued S-fuzzy left h-ideal is introduced,and its characterization is given.S-fuzzy relations on hemirings are discussed.The notion of direct product and S-product are introduced and some properties of the direct product and S-product of S-fuzzy left h-ideal of hemiring are also discussed.
Abstract: Allowing diagonalizability of sign pattern is still an open problem. In this paper, we make a carefully discussion about allowing unitary diagonalizability of two sign pattern. Some sufficient and necessary conditions of allowing unitary diagonalizability are also obtained.
Abstract: Magnesium alloys have gained increased attention in recent years in automotive, electronics, and medical industry. This because of magnesium alloys have better properties than aluminum alloys and steels in respects of their low density and high strength to weight ratio. However, the main problems of magnesium alloy welding are the crack formation and the appearance of porosity during the solidification. This paper proposes a unique technique to weld two thin sheets of AZ31B magnesium alloy using a paste containing Ag nanoparticles. The paste containing Ag nanoparticles of 5 nm in average diameter and an organic solvent was used to coat the surface of AZ31B thin sheet. The coated sheet was heated at 100 °C for 60 s to evaporate the solvent. The dried sheet was set as a lower AZ31B sheet on the jig, and then lap fillet welding was carried out by using a pulsed Nd:YAG laser in a closed box filled with argon gas. The characteristics of the microstructure and the corrosion behavior of the joints were analyzed by opticalmicroscopy (OM), energy dispersive spectrometry (EDS), electron probe micro-analyzer (EPMA), scanning electron microscopy (SEM), and immersion corrosion test. The experimental results show that the wrought AZ31B magnesium alloy can be joined successfully using Ag nanoparticles. Ag nanoparticles insert promote grain refinement, narrower the HAZ width and wider bond width compared to weld without and insert. Corrosion rate of welded AZ31B with Ag nanoparticles reduced up to 44 % compared to base metal. The improvement of corrosion resistance of welded AZ31B with Ag nanoparticles due to finer grains and large grain boundaries area which consist of high Al content. β-phase Mg17Al12 could serve as effective barrier and suppressed further propagation of corrosion. Furthermore, Ag distribution in fusion zone provide much more finer grains and may stabilize the magnesium solid solution making it less soluble or less anodic in aqueous
Abstract: As the disfunctions of the information society and
social development progress, intrusion problems such as malicious
replies, spam mail, private information leakage, phishing, and
pharming, and side effects such as the spread of unwholesome
information and privacy invasion are becoming serious social
problems. Illegal access to information is also becoming a problem as
the exchange and sharing of information increases on the basis of the
extension of the communication network. On the other hand, as the
communication network has been constructed as an international,
global system, the legal response against invasion and cyber-attack
from abroad is facing its limit. In addition, in an environment where
the important infrastructures are managed and controlled on the basis
of the information communication network, such problems pose a
threat to national security. Countermeasures to such threats are
developed and implemented on a yearly basis to protect the major
infrastructures of information communication. As a part of such
measures, we have developed a methodology for assessing the
information protection level which can be used to establish the
quantitative object setting method required for the improvement of the
information protection level.
Abstract: In most of the popular implementation of Parallel GAs
the whole population is divided into a set of subpopulations, each
subpopulation executes GA independently and some individuals are
migrated at fixed intervals on a ring topology. In these studies,
the migrations usually occur 'synchronously' among subpopulations.
Therefore, CPUs are not used efficiently and the communication
do not occur efficiently either. A few studies tried asynchronous
migration but it is hard to implement and setting proper parameter
values is difficult.
The aim of our research is to develop a migration method which is
easy to implement, which is easy to set parameter values, and which
reduces communication traffic. In this paper, we propose a traffic
reduction method for the Asynchronous Parallel Distributed GA by
migration of elites only. This is a Server-Client model. Every client
executes GA on a subpopulation and sends an elite information to the
server. The server manages the elite information of each client and
the migrations occur according to the evolution of sub-population in
a client. This facilitates the reduction in communication traffic.
To evaluate our proposed model, we apply it to many function optimization
problems. We confirm that our proposed method performs
as well as current methods, the communication traffic is less, and
setting of the parameters are much easier.
Abstract: In the last decades, a number of robust fuzzy clustering algorithms have been proposed to partition data sets affected by noise and outliers. Robust fuzzy C-means (robust-FCM) is certainly one of the most known among these algorithms. In robust-FCM, noise is modeled as a separate cluster and is characterized by a prototype that has a constant distance δ from all data points. Distance δ determines the boundary of the noise cluster and therefore is a critical parameter of the algorithm. Though some approaches have been proposed to automatically determine the most suitable δ for the specific application, up to today an efficient and fully satisfactory solution does not exist. The aim of this paper is to propose a novel method to compute the optimal δ based on the analysis of the distribution of the percentage of objects assigned to the noise cluster in repeated executions of the robust-FCM with decreasing values of δ . The extremely encouraging results obtained on some data sets found in the literature are shown and discussed.