Abstract: Design patterns describe good solutions to common
and reoccurring problems in program design. Applying design
patterns in software design and implementation have significant
effects on software quality metrics such as flexibility, usability,
reusability, scalability and robustness. There is no standard rule for
using design patterns. There are some situations that a pattern is
applied for a specific problem and this pattern uses another pattern.
In this paper, we study the effect of using chain of patterns on
software quality metrics.
Abstract: Transpedicular screw fixation in spinal fractures,
degenerative changes, or deformities is a well-established procedure.
However, important rate of fixation failure due to screw bending,
loosening, or pullout are still reported particularly in weak bone stock
in osteoporosis. To overcome the problem, mechanism of failure has
to be fully investigated in vitro. Post-mortem human subjects are less
accessible and animal cadavers comprise limitations due to different
geometry and mechanical properties. Therefore, the development of a
synthetic model mimicking the realistic human vertebra is highly
demanded. A bone surrogate, composed of Polyurethane (PU) foam
analogous to cancellous bone porous structure, was tested for 3
different densities in this study. The mechanical properties were
investigated under uniaxial compression test by minimizing the end
artifacts on specimens. The results indicated that PU foam of 0.32
g.cm-3 density has comparable mechanical properties to human
cancellous bone in terms of young-s modulus and yield strength.
Therefore, the obtained information can be considered as primary
step for developing a realistic cancellous bone of human vertebral
body. Further evaluations are also recommended for other density
groups.
Abstract: Sediment loads transfer in hydraulic installations and their consequences for the O&M of modern canal systems is emerging as one of the most important considerations in hydraulic engineering projects apriticularly those which are inteded to feed the irrigation and draiange schemes of large command areas such as the Dez and Mogahn in Iran.. The aim of this paper is to investigate the applicability of the vortex tube as a viable means of extracting sediment loads entering the canal systems in general and the water inatke structures in particulars. The Western conveyance canal of the Dez Diversion weir which feeds the Karkheh Flood Plain in Sothwestern Dezful has been used as the case study using the data from the Dastmashan Hydrometric Station. The SHARC software has been used as an analytical framework to interprete the data. Results show that given the grain size D50 and the canal turbulence the adaption length from the beginning of the canal and after the diversion dam is estimated at 477 m, a point which is suitable for laying the vortex tube.
Abstract: To achieve accurate and precise results of finite
element analysis (FEA) of bones, it is important to represent the
load/boundary conditions as identical as possible to the human body
such as the bone properties, the type and force of the muscles, the
contact force of the joints, and the location of the muscle attachment.
In this study, the difference in the Von-Mises stress and the total
deformation was compared by classifying them into Case 1, which
shows the actual anatomical form of the muscle attached to the femur
when the same muscle force was applied, and Case 2, which gives a
simplified representation of the attached location. An inverse
dynamical musculoskeletal model was simulated using data from an
actual walking experiment to complement the accuracy of the
muscular force, the input value of FEA. The FEA method using the
results of the muscular force that were calculated through the
simulation showed that the maximum Von-Mises stress and the
maximum total deformation in Case 2 were underestimated by 8.42%
and 6.29%, respectively, compared to Case 1. The torsion energy and
bending moment at each location of the femur occurred via the stress
ingredient. Due to the geometrical/morphological feature of the femur
of having a long bone shape when the stress distribution is wide, as
shown in Case 1, a greater Von-Mises stress and total deformation are
expected from the sum of the stress ingredients. More accurate results
can be achieved only when the muscular strength and the attachment
location in the FEA of the bones and the attachment form are the same
as those in the actual anatomical condition under the various moving
conditions of the human body.
Abstract: Wireless sensor networks (WSNs) have gained
tremendous attention in recent years due to their numerous
applications. Due to the limited energy resource, energy efficient
operation of sensor nodes is a key issue in wireless sensor networks.
Cooperative caching which ensures sharing of data among various
nodes reduces the number of communications over the wireless
channels and thus enhances the overall lifetime of a wireless sensor
network. In this paper, we propose a cooperative caching scheme
called ZCS (Zone Cooperation at Sensors) for wireless sensor
networks. In ZCS scheme, one-hop neighbors of a sensor node form a
cooperative cache zone and share the cached data with each other.
Simulation experiments show that the ZCS caching scheme achieves
significant improvements in byte hit ratio and average query latency
in comparison with other caching strategies.
Abstract: Two commercial proteases from Bacillus
licheniformis (Alcalase 2.4 L FG and Alcalase 2.5 L, Type DX) were
screened for the production of Z-Ala-Phe-NH2 in batch reaction.
Alcalase 2.4 L FG was the most efficient enzyme for the C-terminal
amidation of Z-Ala-Phe-OMe using ammonium carbamate as
ammonium source. Immobilization of protease has been achieved by
the sol-gel method, using dimethyldimethoxysilane (DMDMOS) and
tetramethoxysilane (TMOS) as precursors (unpublished results). In
batch production, about 95% of Z-Ala-Phe-NH2 was obtained at
30°C after 24 hours of incubation. Reproducibility of different
batches of commercial Alcalase 2.4 L FG preparations was also
investigated by evaluating the amidation activity and the entrapment
yields in the case of immobilization. A packed-bed reactor (0.68 cm
ID, 15.0 cm long) was operated successfully for the continuous
synthesis of peptide amides. The immobilized enzyme retained the
initial activity over 10 cycles of repeated use in continuous reactor at
ambient temperature. At 0.75 mL/min flow rate of the substrate
mixture, the total conversion of Z-Ala-Phe-OMe was achieved after 5
hours of substrate recycling. The product contained about 90%
peptide amide and 10% hydrolysis byproduct.
Abstract: The principal objective of this study is to be able to
extract niobium oxide from columbite-tantalite concentrate of Thayet
Kon Area in Nay Phi Taw. It is recovered from columbite-tantalite
concentrate which contains 19.29 % Nb2O5.The recovery of niobium
oxide from columbite-tantalite concentrate can be divided into three
main sections, namely, digestion of the concentrate, recovery from
the leached solution and precipitation and calcinations. The
concentrate was digested with hydrofluoric acid and sulfuric acid. Of
the various parameters that effect acidity and time were studied. In
the recovery section solvent extraction process using methyl isobutyl
ketone was investigated. Ammonium hydroxide was used as a
precipitating agent and the precipitate was later calcined. The
percentage of niobium oxide is 74%.
Abstract: The availability of water in adequate quantity and
quality is imperative for sustainable development. Worldwide,
significant imbalance exists with regards to sustainable development
particularly from a water and sanitation perspective. Water is a
critical component of public health, and failure to supply safe water
will place a heavy burden on the entire population. Although the 21st
century has witnessed wealth and advanced development, it has not
been realized everywhere. Billions of people are still striving to
access the most basic human needs which are food, shelter, safe
drinking water and adequate sanitation. The global picture conceals
various inequalities particularly with regards to sanitation coverage in
rural and urban areas. Currently, water scarcity and in particular
water governance is the main challenge which will cause a threat to
sustainable development goals. Within the context of water,
sanitation and health, sustainable development is a confusing concept
primarily when examined from the viewpoint of policy options for
developing countries. This perspective paper aims to summarize and
critically evaluate evidence of published studies in relation to water,
sanitation and health and to identify relevant solutions to reduce
public health impacts. Evidently, improving water and sanitation
services will result in significant and lasting gains in health and
economic development.
Abstract: The cable tower of Liede Bridge is a double-column curved-lever arched-beam portal framed structure. Being novel and unique in structure, its cable tower differs in complexity from traditional ones. This paper analyzes the ultimate load capacity of cable tower by adopting the finite element calculations and model tests which indicate that constitutive relations applied here give a better simulation of actual failure process of prestressed reinforced concrete. In vertical load, horizontal load and overloading tests, the stepped loading of the tower model is of linear relationship, and the test data has good repeatability. All suggests that the cable tower has good bearing capacity, rational design and high emergency capacity.
Abstract: Given a parallel program to be executed on a heterogeneous
computing system, the overall execution time of the program
is determined by a schedule. In this paper, we analyze the worst-case
performance of the list scheduling algorithm for scheduling tasks
of a parallel program in a mixed-machine heterogeneous computing
system such that the total execution time of the program is minimized.
We prove tight lower and upper bounds for the worst-case
performance ratio of the list scheduling algorithm. We also examine
the average-case performance of the list scheduling algorithm. Our
experimental data reveal that the average-case performance of the list
scheduling algorithm is much better than the worst-case performance
and is very close to optimal, except for large systems with large
heterogeneity. Thus, the list scheduling algorithm is very useful in
real applications.
Abstract: Cryptography provides the secure manner of
information transmission over the insecure channel. It authenticates
messages based on the key but not on the user. It requires a lengthy
key to encrypt and decrypt the sending and receiving the messages,
respectively. But these keys can be guessed or cracked. Moreover,
Maintaining and sharing lengthy, random keys in enciphering and
deciphering process is the critical problem in the cryptography
system. A new approach is described for generating a crypto key,
which is acquired from a person-s iris pattern. In the biometric field,
template created by the biometric algorithm can only be
authenticated with the same person. Among the biometric templates,
iris features can efficiently be distinguished with individuals and
produces less false positives in the larger population. This type of iris
code distribution provides merely less intra-class variability that aids
the cryptosystem to confidently decrypt messages with an exact
matching of iris pattern. In this proposed approach, the iris features
are extracted using multi resolution wavelets. It produces 135-bit iris
codes from each subject and is used for encrypting/decrypting the
messages. The autocorrelators are used to recall original messages
from the partially corrupted data produced by the decryption process.
It intends to resolve the repudiation and key management problems.
Results were analyzed in both conventional iris cryptography system
(CIC) and non-repudiation iris cryptography system (NRIC). It
shows that this new approach provides considerably high
authentication in enciphering and deciphering processes.
Abstract: This paper presents a threshold voltage model of pocket implanted sub-100 nm n-MOSFETs incorporating the drain and substrate bias effects using two linear pocket profiles. Two linear equations are used to simulate the pocket profiles along the channel at the surface from the source and drain edges towards the center of the n-MOSFET. Then the effective doping concentration is derived and is used in the threshold voltage equation that is obtained by solving the Poisson-s equation in the depletion region at the surface. Simulated threshold voltages for various gate lengths fit well with the experimental data already published in the literature. The simulated result is compared with the two other pocket profiles used to derive the threshold voltage models of n-MOSFETs. The comparison shows that the linear model has a simple compact form that can be utilized to study and characterize the pocket implanted advanced ULSI devices.
Abstract: The vast amount of information on the World Wide
Web is created and published by many different types of providers.
Unlike books and journals, most of this information is not subject to
editing or peer review by experts. This lack of quality control and the
explosion of web sites make the task of finding quality information
on the web especially critical. Meanwhile new facilities for
producing web pages such as Blogs make this issue more significant
because Blogs have simple content management tools enabling nonexperts
to build easily updatable web diaries or online journals. On
the other hand despite a decade of active research in information
quality (IQ) there is no framework for measuring information quality
on the Blogs yet. This paper presents a novel experimental
framework for ranking quality of information on the Weblog. The
results of data analysis revealed seven IQ dimensions for the Weblog.
For each dimension, variables and related coefficients were
calculated so that presented framework is able to assess IQ of
Weblogs automatically.
Abstract: This paper mainly investigates the environmental and
economic impacts of worldwide use of electric vehicles. It can be
concluded that governments have good reason to promote the use of
electric vehicles. First, the global vehicles population is evaluated with
the help of grey forecasting model and the amount of oil saving is
estimated through approximate calculation. After that, based on the
game theory, the amount and types of electricity generation needed by
electronic vehicles are established. Finally, some conclusions on the
government-s attitudes are drawn.
Abstract: Simulation is a very powerful method used for highperformance
and high-quality design in distributed system, and now
maybe the only one, considering the heterogeneity, complexity and
cost of distributed systems. In Grid environments, foe example, it is
hard and even impossible to perform scheduler performance
evaluation in a repeatable and controllable manner as resources and
users are distributed across multiple organizations with their own
policies. In addition, Grid test-beds are limited and creating an
adequately-sized test-bed is expensive and time consuming.
Scalability, reliability and fault-tolerance become important
requirements for distributed systems in order to support distributed
computation. A distributed system with such characteristics is called
dependable. Large environments, like Cloud, offer unique
advantages, such as low cost, dependability and satisfy QoS for all
users. Resource management in large environments address
performant scheduling algorithm guided by QoS constrains. This
paper presents the performance evaluation of scheduling heuristics
guided by different optimization criteria. The algorithms for
distributed scheduling are analyzed in order to satisfy users
constrains considering in the same time independent capabilities of
resources. This analysis acts like a profiling step for algorithm
calibration. The performance evaluation is based on simulation. The
simulator is MONARC, a powerful tool for large scale distributed
systems simulation. The novelty of this paper consists in synthetic
analysis results that offer guidelines for scheduler service
configuration and sustain the empirical-based decision. The results
could be used in decisions regarding optimizations to existing Grid
DAG Scheduling and for selecting the proper algorithm for DAG
scheduling in various actual situations.
Abstract: This paper presents two prototypes of low power low voltage current mode 9 bit pipelined a/d converters. The first and the second converters are configured of 1.5 bit and 2.5 bit stages, respectively. The a/d converter structures are composed of current mode building blocks and final comparator block which converts the analog current signal into digital voltage signal. All building blocks have been designed in CMOS AMS 0.35μm technology, then simulated to verify proposed concept. The performances of both converters are compared to performances of known current mode and voltage mode switched capacitance converter structures. Low power consumption and small chip area are advantages of the proposed converters.
Abstract: This paper proposes a delay-dependent leader-following consensus condition of multi-agent systems with both communication delay and probabilistic self-delay. The proposed methods employ a suitable piecewise Lyapunov-Krasovskii functional and the average dwell time approach. New consensus criterion for the systems are established in terms of linear matrix inequalities (LMIs) which can be easily solved by various effective optimization algorithms. Numerical example showed that the proposed method is effective.
Abstract: In this paper, we have compared the performance of a Turbo and Trellis coded optical code division multiple access (OCDMA) system. The comparison of the two codes has been accomplished by employing optical orthogonal codes (OOCs). The Bit Error Rate (BER) performances have been compared by varying the code weights of address codes employed by the system. We have considered the effects of optical multiple access interference (OMAI), thermal noise and avalanche photodiode (APD) detector noise. Analysis has been carried out for the system with and without double optical hard limiter (DHL). From the simulation results it is observed that a better and distinct comparison can be drawn between the performance of Trellis and Turbo coded systems, at lower code weights of optical orthogonal codes for a fixed number of users. The BER performance of the Turbo coded system is found to be better than the Trellis coded system for all code weights that have been considered for the simulation. Nevertheless, the Trellis coded OCDMA system is found to be better than the uncoded OCDMA system. Trellis coded OCDMA can be used in systems where decoding time has to be kept low, bandwidth is limited and high reliability is not a crucial factor as in local area networks. Also the system hardware is less complex in comparison to the Turbo coded system. Trellis coded OCDMA system can be used without significant modification of the existing chipsets. Turbo-coded OCDMA can however be employed in systems where high reliability is needed and bandwidth is not a limiting factor.
Abstract: Proteomics is one of the largest areas of research for
bioinformatics and medical science. An ambitious goal of proteomics
is to elucidate the structure, interactions and functions of all proteins
within cells and organisms. Predicting Protein-Protein Interaction
(PPI) is one of the crucial and decisive problems in current research.
Genomic data offer a great opportunity and at the same time a lot of
challenges for the identification of these interactions. Many methods
have already been proposed in this regard. In case of in-silico
identification, most of the methods require both positive and negative
examples of protein interaction and the perfection of these examples
are very much crucial for the final prediction accuracy. Positive
examples are relatively easy to obtain from well known databases. But
the generation of negative examples is not a trivial task. Current PPI
identification methods generate negative examples based on some
assumptions, which are likely to affect their prediction accuracy.
Hence, if more reliable negative examples are used, the PPI prediction
methods may achieve even more accuracy. Focusing on this issue, a
graph based negative example generation method is proposed, which
is simple and more accurate than the existing approaches. An
interaction graph of the protein sequences is created. The basic
assumption is that the longer the shortest path between two
protein-sequences in the interaction graph, the less is the possibility of
their interaction. A well established PPI detection algorithm is
employed with our negative examples and in most cases it increases
the accuracy more than 10% in comparison with the negative pair
selection method in that paper.
Abstract: The communication networks development and
advancement during two last decades has been toward a single goal
and that is gradual change from circuit-switched networks to packed
switched ones. Today a lot of networks operates are trying to
transform the public telephone networks to multipurpose packed
switch. This new achievement is generally called "next generation
networks". In fact, the next generation networks enable the operators
to transfer every kind of services (sound, data and video) on a
network. First, in this report the definition, characteristics and next
generation networks services and then ad-hoc networks role in the
next generation networks are studied.