When elementary quantum systems, such as polarized photons,
are used to transmit digital information, the uncertainty principle gives rise
to novel cryptographic phenomena unachievable with traditional transmission
media, e.g. a communications channel on which it is impossible in principle to
eavesdrop without a high probability of disturbing the transmission in such a
way as to be detected. Such a quantum channel can be used in conjunction with ordinary
insecure classical channels to distribute random key information between two
users with the assurance that it remains unknown to anyone else, even when the
users share no secret information initially. We also present a protocol for
coin-tossing by exchange of quantum messages, which is secure against
traditional kinds of cheating, even by an opponent with unlimited computing
power, but ironically can be subverted by use of a still subtler quantum
phenomenon, the Einstein–Podolsky–Rosen paradox.
Sunday, 31 May 2015
Ant colony optimization theory: A survey
Research on a new metaheuristic for optimization is often
initially focused on proof-of-concept applications. It is only after
experimental work has shown the practical interest of the method that
researchers try to deepen their understanding of the method's functioning not
only through more and more sophisticated experiments but also by means of an
effort to build a theory. Tackling questions such as “how and why the method
works’’ is important, because finding an answer may help in improving its
applicability. Ant colony optimization, which was introduced in the early 1990s
as a novel technique for solving hard combinatorial optimization problems,
finds itself currently at this point of its life cycle. With this article we
provide a survey on theoretical results on ant colony optimization. First, we
review some convergence results. Then we discuss relations between ant colony
optimization algorithms and other approximate methods for optimization.
Finally, we focus on some research efforts directed at gaining a deeper
understanding of the behavior of ant colony optimization algorithms. Throughout
the paper we identify some open questions with a certain interest of being
solved in the near future.
Some simplified NP-complete graph problems
It is widely believed that showing a problem to be
NP-complete is tantamount to proving its computational intractability. In this
paper we show that a number of NP-complete problems remain NP-complete even
when their domains are substantially restricted. First we show the completeness
of Simple Max Cut (Max Cut with edge weights restricted to value 1), and, as a
corollary, the completeness of the Optimal Linear Arrangement problem. We then
show that even if the domains of the Node Cover and Directed Hamiltonian Path
problems are restricted to planar graphs, the two problems remain NP-complete,
and that these and other graph problems remain NP-complete even when their
domains are restricted to graphs with low node degrees. For Graph 3-Colorability,
Node Cover, and Undirected Hamiltonian Circuit, we determine essentially the
lowest possible upper bounds on node degree for which the problems remain
NP-complete.
Bigraphs with sharing
Bigraphical
Reactive Systems (BRS) were designed by Milner as a universal formalism for
modelling systems that evolve in time, locality, co-locality and connectivity.
But the underlying model of location (the place graph) is a forest, which means
there is no straightforward representation of locations that can overlap or intersect.
This occurs in many domains, for example in wireless signalling, social
interactions and audio communications. Here, we define bigraphs with sharing,
which solves this problem by an extension of the basic formalism: we define the
place graph as a directed acyclic graph, thus allowing a natural representation
of overlapping or intersecting locations.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Design and analysis of different alternating variable searches for search-based software testing
Manual
software testing is a notoriously expensive part of the software development
process, and its automation is of high concern. One aspect of the testing
process is the automatic generation of test inputs. This paper studies the
Alternating Variable Method (AVM) approach to search-based test input generation.
The AVM has been shown to be an effective and efficient means of generating
branch-covering inputs for procedural programs. However, there has been little
work that has sought to analyse the technique and further improve its
performance. This paper proposes two different local searches that may be used
in conjunction with the AVM, Geometric and Lattice Search. A theoretical
runtime analysis proves that under certain conditions, the use of these
searches results in better performance compared to the original AVM. These
theoretical results are confirmed by an empirical study with five programs,
which shows that increases of speed of over 50% are possible in practice.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
A framework for co-optimization algorithm performance and its application to worst-case optimization
Traditional
black-box optimization searches a set of potential solutions for those
optimizing the value of a function whose analytical or algebraic form is
unknown or inexistent, but whose value can be queried for any input.
Co-optimization is a generalization of this setting, in which fully evaluating
a potential solution may require querying some function more than once,
typically a very large number of times. When that's the case, co-optimization
poses unique difficulties to designing and assessing algorithms. A
generally-applicable approach is to judge co-optimization algorithm performance
via an aggregate over all possible functions in the problem domain.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Unveiling metamorphism by abstract interpretation of code properties
Metamorphic
code includes self-modifying semantics-preserving transformations to exploit
code diversification. The impact of metamorphism is growing in security and
code protection technologies, both for preventing malicious host attacks, e.g.,
in software diversification for IP and integrity protection, and in malicious
software attacks, e.g., in metamorphic malware self-modifying their own code in
order to foil detection systems based on signature matching. In this paper we
consider the problem of automatically extracting metamorphic signatures from
metamorphic code. We introduce a semantics for self-modifying code, later
called phase semantics, and prove its correctness by showing that it is an
abstract interpretation of the standard trace semantics. Phase semantics
precisely models the metamorphic code behavior by providing a set of traces of
programs which correspond to the possible evolutions of the metamorphic code
during execution. We show that metamorphic signatures can be automatically
extracted by abstract interpretation of the phase semantics. In particular, we
introduce the notion of regular metamorphism, where the invariants of the phase
semantics can be modeled as finite state automata representing the code
structure of all possible metamorphic change of a metamorphic code, and we
provide a static signature extraction algorithm for metamorphic code where
metamorphic signatures are approximated in regular metamorphism.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Fast distributed PageRank computation
Over the last decade, PageRank has gained importance in a
wide range of applications and domains, ever since it first proved to be
effective in determining node importance in large graphs (and was a pioneering
idea behind Google's search engine). In distributed computing alone, PageRank
vector, or more generally random walk based quantities have been used for
several different applications ranging from determining important nodes, load
balancing, search, and identifying connectivity structures. Surprisingly,
however, there has been little work towards designing provably efficient
fully-distributed algorithms for computing PageRank. The difficulty is that
traditional matrix–vector multiplication style iterative methods may not always
adapt well to the distributed setting owing to communication bandwidth
restrictions and convergence rates.
On the variable common due date, minimal tardy jobs bicriteria two-machine flow shop problem with ordered machines
We
consider a special case of the ordinary NP-hard two-machine flow shop problem
with the objective of determining simultaneously a minimal common due date and
the minimal number of tardy jobs. In Panwalkar and Koulamas (2012) [5], the
authors presented quadratic algorithm for the problem when each job has its
smaller processing time on the first machine. In this note, we improve the
running time of the algorithm to O(nlogn)
by efficient implementation using recently introduced modified binary tree data
structure.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
A fixed point theorem for non-monotonic functions
We present a fixed point theorem for a class of
(potentially) non-monotonic functions over specially structured complete
lattices. The theorem has as a special case the Knaster–Tarski fixed point
theorem when restricted to the case of monotonic functions and Kleene's theorem
when the functions are additionally continuous. From the practical side, the
theorem has direct applications in the semantics of negation in logic
programming. In particular, it leads to a more direct and elegant proof of the
least fixed point result of. Moreover, the theorem appears to have potential
for possible applications outside the logic programming domain.
website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Integrated production and delivery scheduling on a serial batch machine to minimize the makespan
In this paper, we study the integrated
production and delivery scheduling on a serial batch machine. The objective is
to minimize the makespan, i.e., the maximum delivery completion time of the
jobs. We consider four distinct problems which depend on whether split is
allowed in the production or delivery of the jobs. We present a polynomial-time
algorithm for the first problem and show that other three problems are strongly
NP-hard. Furthermore, we provide effective approximation algorithms for the three
NP-hard problems.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
The black paper of quantum cryptography: Real implementation problems
The laws of physics play a crucial role in the
security of quantum key distribution (QKD). This fact has often been
misunderstood as if the security of QKD would be based only on the laws of
physics. As the experts know well, things are more subtle. We review the
progresses in practical QKD focusing on (I) the elements of trust that are
common to classical and quantum implementations of key distribution; and (II)
some threats to security that have been highlighted recently, none of which is
unredeemable (i.e., in principle QKD can be made secure). This leads us to
guess that the field, similar to non-quantum modern cryptography, is going to
split in two directions: those who pursue practical devices may have to
moderate their security claims; those who pursue ultimate security may have to
suspend their claims of usefulness.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Global and local sequence alignment with a bounded number of gaps
Pairwise sequence alignment techniques
have gained renewed interest in recent years, primarily due to their
applications in re-sequencing—the assembly of a genome directed by a reference
sequence.
In this article, we show that adding the
flexibility of bounding the number of gaps inserted in an alignment strengthens
the classical sequence alignment scheme of scoring matrices and affine gap
penalty scores. We present GapsMis, an algorithm for pairwise global sequence
alignment with a variable, but bounded, number of gaps. It is based on
computing a variant of the traditional dynamic programming matrix for global
sequence alignment. We also present GapsMis-L, the analogous algorithm for
pairwise local sequence alignment with a variable, but bounded, number of gaps.
A derivative for complex Lipschitz maps with generalized Cauchy–Riemann equations
We introduce the Lipschitz derivative or the
L-derivative of a locally Lipschitz complex map: it is a Scott continuous,
compact and convex set-valued map that extends the classical derivative to the
bigger class of locally Lipschitz maps and allows an extension of the
fundamental theorem of calculus and a new generalisation of Cauchy–Riemann
equations to these maps, which form a continuous Scott domain. We show that a
complex Lipschitz map is analytic in an open set if and only if its
L-derivative is a singleton at all points in the open set. The calculus of the
L-derivative for sum, product and composition of maps is derived. The notion of
contour integration is extended to Scott continuous, non-empty compact, convex
valued functions on the complex plane, and by using the L-derivative, the
fundamental theorem of contour integration is extended to these functions.
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Website: http://www.arjonline.org/engineering/american-research-journal-of-computer-science-and-information-technology/
Friday, 29 May 2015
Effects of Building Configuration on Seismic Performance of RC Buildings by Pushover Analysis
In the recent earthquakes,
concrete structures have been severely damaged or collapsed, which has raised
questions against the seismic adequacy of existing buildings. These existing
reinforced concrete buildings need to be evaluated to determine the capacity to
resist seismic loads. The behavior of a building during earthquakes depends
critically on its overall shape, size and geometry. Conventional approach to
earthquake resistant design of buildings depends upon providing the building
with strength, stiffness and inelastic deformation capacity which are great
enough to withstand a given level of earthquake-generated force. This is
generally accomplished through the selection of an appropriate building
configuration and the careful detailing of structural members. In this
research, nonlinear pushover analysis has been used to evaluate the seismic
performance of three buildings with three different plans having same area and
height. This method determines the base shear capacity of the building and
performance level of each part of building under varying intensity of seismic
force. The results of effects of different plan on seismic response of
buildings have been presented in terms of displacement, base shear and plastic
hinge pattern.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Evaluation of Water Distribution Jointed Pipe Networks under Transient Ground Motions
In this study, a new method
is proposed to evaluate the seismic behavior of buried jointed water pipeline
networks subjected to wave propagation. First, using finite element method and
solid elements, different kinds of currently used connections in the network
are modeled, and their nonlinear behavior in all directions is obtained.
Second, a 950-meter long network consisting of ductile iron pipes segments of
6-meter length and springs characterizing the connections, are modeled using
beam elements. Three-component displacement record of the Tabas earthquake is
applied to the network considering the time lag between support inputs, and the
nonlinear soil-pipe interaction. The record is applied once in North-South
direction and once in East-West direction with different wave propagation
velocities. Results of interest such as stress values and rotations at various
points of the network are then obtained, and critical points are introduced in
each direction. Results show that the points other than the critical ones at
the network intersections remain elastic.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Applications and Prospects of Fiber Reinforced Concrete in Industrial Floors
Upon the view of this work,
industrial floor is a vital structure due to its relation to quality of
production, labor comfort, and human health. Flooring costs may reach 20% of
single-story building construction expenditure, and the consumption of concrete
for floors may come to 40% - 50% of the total size of concrete. Thereby, the
efficient design of floor will reduce materials consumption and labor, and will
increase the endurance of the floor. Fiber reinforcement reduces the thickness
of the subfloor about 20% - 30%, hence enabling to reduce the consumption of
cement and fillers. The use of fiber meshes will enable to save 30% - 40% of
steel. Despite the flexible use of fiber in concrete reinforcement saves effort
and money, still fiber reinforced concrete is lacking additional regulations in
Jordan.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Studies on Strength and Related Properties of Concrete Incorporating Aggregates from Demolished Wastes: Part 2—Compressive and Flexural Strength
In an earlier study, a
comprehensive and critical review of previous investigations into the
assessment of the strength of concrete incorporating aggregates from demolished
wastes was conducted and it was concluded that there was a stark absence of
results from the South African sub-continent including Botswana. In the present
study, recycled coarse aggregates (RCA) sourced from demolished wastes
collected from a landfill site in Gaborone, Botswana was used in lieu of
natural coarse aggregates for the manufacture of concrete. With reference to
the natural coarse aggregate, RCA replacement levels of 0%, 20%, 40%, 60%, 80%
and 100% were utilized and the results of hardened concrete tests for
compressive and flexural strengths were obtained. It was found that in general
the compressive and flexural strengths of the recycled aggregate concrete (RAC)
decreased with increasing replacement levels of natural coarse aggregates using
RCA. It was concluded that RCA could be employed as a substitute for natural
aggregate in concrete only up to a certain limit or partial replacement. In
this respect, it was also noted that the undesirable properties of RCA were
primarily due to the quantity and quality of the adhering mortar.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Seismic Capacity Assessment of Existing RC Buildings in The Sudan by Using Pushover Analysis
Recently, the evaluation of
seismic performance of existing buildings has received a great attention.
Current research works and observations indicate that The Sudan have
low-to-moderate seismic regions. Most of existing buildings are designed only
for gravity load. The objective of this paper is to assess the seismic
performance of existing RC buildings in The Sudan. Four typical buildings were
investigated using pushover analysis according to ATC-40. They were designed
according to the Regulations for earthquake-resistant design of buildings in
Egypt (ESEE) and International Building Code (IBC2012). Results showed that the
buildings designed considering by ESEE and IBC2012 loads were found adequate
and satisfied the Immediate Occupancy (IO) acceptance criteria according to
ATC-40. The comparison of the pushover curve shows that the stiffness of frames
is larger when using ESEE Regulations compared to the IBC2012 design. This
means that ESEE design procedure provides a greater capability to resist
seismic load than the IBC2012 design.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Analysis of Control Measures for Settlement of Differences on the Problems of Highway Subgrade Widening
The study mainly discusses
the issues of the settlement of differences that occurs in the process of
highway subgrade widening. Firstly, it briefly introduces the settlement of
difference and its harms; then it analyzes the mechanism of settlement of
differences in the process of difference widening, including four aspects: the
new and old roadbeds themselves, design, construction and other links; finally,
based on the above analysis of the mechanism, it discusses the corresponding
control measures, mainly proposing these suggestions as followings: the use of
lightweight materials, the foundation treatment, the cut slope excavation
steps, and the strict control of the degree of compaction, etc. The paper is
expected to provide some theoretical basis for the control measures of highway
subgrade widening settlement of difference.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
A Study on Water Repellent Effectiveness of Natural Oil-Applied Soil as a Building Material
This study was performed to
investigate the water repellent effectiveness of natural oil-applied soil when
it is used as a building material. Natural oil types such as olive oil, bean
oil, perilla oil and linseed oil, which are being used for producing water
repellent timber, are selected for the experiments. It is expected that perilla
oil and in seed oil, which are drying oil types will have better water
repellent effectiveness than the other types. For the evaluation of water
repellence of natural oil-applied soil, a contact angle test was performed. A
contact angle of water drop on various surface conditions were tested, and
large differences were seen between the natural oil-applied soil and untreated
soil. As a result, it is showed that all natural oil types have water repellent
effectiveness. However, linseed oil, which is a drying oil type, shows an
outstanding water repellent effectiveness value, while perila oil, which is
also a drying oil type, shows the lowest value. Additionally, results show that
there is no link between water repellent effectiveness and the number of
applications of natural oil. Nevertheless, existing commercial water repellents
show better performance than natural oil, and it is anticipated that the
results of this study will provide essential information for further research
to enhance the water repellent effectiveness of soil as a building material.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
The Effect of Incorporation of Ferrite Nano-particles on Compressive Strength and Re-sistivity of Self-Compacting Concrete
Mn-Ferrite nanoparticles
were prepared using citrate auto combustion method. The prepared sample was
characterized by X-ray diffraction (XRD), HRTEM and BET to measure the particle
diameter and the surface area of the prepared sample. The data of XRD clarified
that the sample was formed in single phase spinel structure without any extra
peaks indicating non-existence of any secondary phase. The HRTEM micrograph
indicated that the particles were in an agglomerated state due to the absence
of surfactant and high magnetic properties of Mn-Ferrite nanoparticles. The
mechanical properties were measured at different ratios of nano-Ferrite to
concrete. The obtained values of mercury intrusion porosimetry (MIP) indicated
that the addition of Mn-Ferrite nanoparticles increased the compressive
strength and decreased the total intrusion volume. This was due to the rapid
consuming of Ca(OH)2 which was formed during hydration of Portland cement
especially at early ages due to the high reactivity of MnFe2O4 nanoparticles.
Moreover, MnFe2O4 nanoparticles recovered the particle packing density of the
blended cement, leading to a reduced volume of pores in the cement paste.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Parametric Study for Replacement of Sand by Fly Ash for Better Packing and Internal Curing
The use of fly ash as
replacement of sand is an economical solution for making green and denser
concrete. The paper presents a concrete mix design procedure for partial
replacement of sand with fly ash. Present method could produce additional
compressive and flexural strength for concrete with partial replacement of sand
with fly ash over control concrete, with higher slump. Addition of 0.5% super
plasticizer could further improve compressive and flexural strength with higher
slump over control concrete. Concrete with sand replaced by fly ash was also
found to be economical without and with super plasticizer, when cost per N/mm2
was compared. The beneficial effect may be attributed to better packing,
pozzolanic activity of fly ash and internal curing by fly ash as partial
replacement of sand. Based on experimental results, correlations are developed
to predict compressive strength, flexural strength and cost per N/mm2 for
percentage sand replacement with fly ash.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Influence Analysis of a New Building to the Bridge Pile Foundation Construction
This paper is based on the
analysis of an industrial factory building to the bridge pile foundation
construction stability, and it researches the influence of a new building to
the bridge pile foundation internal force by the finite element analysis
software ANSYS. By calculating the changes of displacement and internal force
of the bridge pile foundation, the deformation can be better controlled.
Furthermore, comparing the data of numerical analysis with one of monitor
measurements, we conclude that a new building has a small influence on the
deformation under load action and the stress variation of a bridge pile
foundation. That is to say, the bridge pile foundation is safe and stable under
load action.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Investigation and Analysis of Urban Spatial Structure around the Train Stations in Kitakyushu by Using Space Syntax and GIS
Although many methods of
spatial analysis have been developed for a better understanding and modelling
of urban space analysis, there is still a need for exploration of new
analytical techniques for modelling urban spaces. Space Syntax models the
spatial configurations of urban spaces by using a connectivity graph
representation. Such a configuration of space identifies patterns that can be
used to study urban structures and human behaviors. This paper tries to present
a new methodology to investigate the urban spatial structure by using Space
Syntax with the GIS information including land use, buildings’ characteristics
and practical evaluations of the potential of the Space Syntax approach with
GIS and multivariate analysis technique.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Anisotropic Damage Mechanics Modeling of Concrete under Biaxial Fatigue Loading
An anisotropic damage
mechanics model is presented to describe the behavior and failure of concrete
under biaxial fatigue loading. Utilizing the approach of bounding surfaces, the
limit surface becomes a special case when the number of loading cycles is set
to one. By increasing the number of loading cycles, the strength of concrete
gradually decreases and the limit surface is allowed to contract and form new
curves representing residual strengths. The magnitude of loading, load range,
and the load path are known to influence the fatigue life and hence are
addressed in this formulation. In this paper, a strength softening function is
proposed in order to address the reduction in the strength of concrete due to
fatigue. Separate softening functions are also proposed to account for the
deformation characteristics in concrete under cyclic loading. Numerical
simulations predicted by the model in both uniaxial and biaxial stress paths
show a good correlation with the experimental data available in the literature.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Computer engineering in designing and fabrication of tissue analogue-type coating dedicated for the cardiovascular regeneration
The work was related to the
development of novel methods in designing and fabrication of thin, porous,
tissue-like coatings. The surface modification was designed to create an
environment for the appropriate cell growth. The originally designed system was
established to prepare porous, synthetic coatings. The dedicated software was
elaborated to control the sequential coating deposition based on the
electrostatic interaction. The finite elements method (FEM) was used to
determine structural and mechanical properties of the coatings. The numerical
model was verified experimentally. The performed simulation predicted the
coating stabilization by the graphene nanoparticles. Graphene was introduced as
a stabilizer of the polymer coating. The elaborated automatic system allowed
preparation the porous coatings, repetitively. Coatings were stabilized by the
cross-linking chemical reaction using
1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide.
Nanoparticles were introduced by means of the electrostatic interaction.
Mechanical analysis revealed an influence of the porous structure modification
on the coating stiffness. Dynamic tests on blood subjected to the aortic flow
showed antithrombogenic properties of the elaborated coatings.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Vibration and dynamic loads in external gear pumps
This paper presents the
model for simulation of vibration and dynamic loads in external gear pumps. The
calculation has been carried out in Matlab/Simulink program. The vibrations of
gears are excited due to the variable pressure forces and variable stiffness of
the gearing. In this model the stiffness and damping coefficient of sliding
bearings as well as the bending stiffness of gear wheels have been included.
The influence of pressure and rotational speed on the dynamic forces in the
bearings have been analyzed.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Static analysis of functionally graded thin rectangular plates with various boundary supports
Present study deals with
static analysis of functionally graded (FG) rectangular plates subjected to
various possible boundary conditions within the framework of classical plate
theory. Material properties of the FG plate are assumed to vary continuously in
the thickness direction according to power-law form. The trial functions
denoting the transverse deflection of the plate are expressed as simple
algebraic polynomials. Uniformly distributed load (UDL) and hydrostatic
pressure are considered to be the external mechanical loads. Rayleigh–Ritz
method along with mechanical kinematic relations and non-dimensionalization
technique are employed in the numerical modeling to obtain the system of linear
equations for the pure bending. Here the main objective is to study the effect
of aspect ratio and volume fraction of the constituents on numerical factors
associated with centroidal deflection, bending moments and normal stresses. New
results for these factors are presented after checking the convergence pattern
and validation has been done with the available results in special cases.
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Website: http://www.arjonline.org/engineering/american-research-journal-of-civil-and-structural-engineering/
Sunday, 24 May 2015
Acta Mechanica Solida Sinica
Acta Mechanica Solida Sinica aims to become the best journal
of solid mechanics in China and the known one in the world in the field of
mechanics, by building up an international exchange platform for the ecological
research; providing original, perspective and even breakthrough theories and
methods for the research on solid mechanics in China and in the world; serving
the sustainable development worldwide.
The Journal is devoted to the publication of research papers
in English in all fields of the solid-state mechanics and its related
disciplines in science, technology, and engineering, with a balanced coverage
on analytical, experimental, numerical and applied investigations. Articles,
Letters, Discussions on previously published papers, and invitation-based
Reviews are published bimonthly. No length limitations for regular and review
articles are set. Letters (4 pages or less) that report novel theories, experimental
and numerical findings, are usually published within three months after
receipt. Papers which are merely methodological without showing essential
advantages in applications, and papers which do not study deformable solids are
out of the score of the Journal.
Aerospace Science and Technology
Aerospace Science and Technology publishes articles of
outstanding scientific quality. Each article is reviewed by two referees. The
journal welcomes papers from a wide range of countries. This journal publishes
original papers, review articles and short communications related to all fields
of aerospace research, fundamental and applied, potential applications of which
are clearly related to:
• The design and the manufacture of aircraft, helicopters,
missiles, launchers and satellites
• The control of their environment
• The study of various systems they are involved in, as
supports or as targets.
Dynamic analysis of the influence of fiber orientation in composite laminated plates
This paper evaluates numerically the dynamic behavior of structural composite laminate materials in relation to the angular change in fiber layers of the laminated composite. The behavior of the material is modeled through finite element method, where the First Order Shear Deformation Theory (FSDT) is used which is implemented on a rectangular element serendipity containing eight nodes. The mathematical modeling has been implemented using the commercial available software MATLAB®. Through numerical simulations, it will be possible to obtain the natural frequencies. And we will present a sensitivity analysis with respect to the fiber orientation parameter.
Website: http://www.arjonline.org/engineering/american-research-journal-of-mechanical-and-automation-engineering/
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