Abstract: Dissimilar joining of Titanium and Aluminum thin
sheets has potential applications in aerospace and automobile
industry which can reduce weight and cost and improve strength,
corrosion resistance and high temperature properties. However
successful welding of Titanium/Aluminium sheets is of challenge due
to differences in physical, chemical and metallurgical properties
between the two. This paper describes research results of Laser Beam
Welding (LBW) of Ti/Al thin sheets in which many researchers have
recently performed and critically reviewed from different
perspectives. Also some of notable works in the field of laser welding
with changes in mechanical properties, crack propagation, diffusion
behavior, chemical potential, interfacial reaction and the
microstructure are reported.
Abstract: Laser beam welding is an important joining technique
for Titanium/Aluminum thin sheet alloys with their increasing
applications in aerospace, aircraft, automotive, electronics and other
industries. In this paper the research and progress in laser welding of
Ti/Al thin sheets are critically reviewed from different perspectives.
Some important aspects such as microstructure, metallurgical defects
and mechanical properties in weldments are discussed. Also the
recent progress in laser welding of Ti/Al dissimilar thin sheets to
provide a basis for further research work is reported.
Abstract: Laser beam welding for the dissimilar Titanium and
Aluminium thin sheets is an emerging area which is having wider
applications in aerospace, aircraft, automotive, electronics and in
other industries due to its high speed, non-contact, precision with low
heat effects, least welding distortion, low labor costs and convenient
operation. Laser beam welding of dissimilar metal combinations are
increasingly demanded due to high energy densities with small fusion
and heat affected zones. Furthermore, no filler or electrode material is
required and contamination of weld is also very small. The present
study is to reviews the influence of different parameters like laser
power, welding speed, power density, beam diameter, focusing
distance and type of shielding gas on the mechanical properties of
dissimilar metal combinations like SS/Al, Cu/Al and Ti/Al focusing
on aluminum to other materials. Research findings reveal that Ti/Al
combination gives better metallurgical and mechanical properties
than other combinations such as SS/Al and Cu/Al.
Abstract: Artificial Immune Systems (AIS), inspired by the
human immune system, are algorithms and mechanisms which are
self-adaptive and self-learning classifiers capable of recognizing and
classifying by learning, long-term memory and association. Unlike
other human system inspired techniques like genetic algorithms and
neural networks, AIS includes a range of algorithms modeling on
different immune mechanism of the body. In this paper, a mechanism
of a human immune system based on apoptosis is adopted to build an
Intrusion Detection System (IDS) to protect computer networks.
Features are selected from network traffic using Fisher Score. Based
on the selected features, the record/connection is classified as either
an attack or normal traffic by the proposed methodology. Simulation
results demonstrates that the proposed AIS based on apoptosis
performs better than existing AIS for intrusion detection.
Abstract: The primary purpose of this paper is to explain the
impact of successful classroom management on the academic
achievements of students, the importance of positive relationship
between teacher and students, among students, between teacher and
parents. Effective communication plays an important role to
encourage students study hard and learn materials which are covered
by the teacher in the class. Friendly relationships among students
other than their preferred friends help them to have team working and
be socialized. In addition, a well-organized classroom arrangement
enhances students learning. As the consequence of successful
classroom management students should feel responsibility and need
to feel it. The one who is responsible to provide a comfortable
environment and help students learn is the manager of the classroom
who is named Teacher.
Abstract: Wireless sensor network is vulnerable to a wide range
of attacks. Recover secrecy after compromise, to develop technique
that can detect intrusions and able to resilient networks that isolates
the point(s) of intrusion while maintaining network connectivity for
other legitimate users. To define new security metrics to evaluate
collaborative intrusion resilience protocol, by leveraging the sensor
mobility that allows compromised sensors to recover secure state
after compromise. This is obtained with very low overhead and in a
fully distributed fashion using extensive simulations support our
findings.
Abstract: In today’s era, it is no news that organizations should
demonstrate honest conduct as well as ethical administration.
Therefore, the concept of corporate social responsibility
(subsequently CSR) has created its tag upon the company’s focal
point as well as marketing communications, and will continue in the
future. The importance of CSR has increased in the last decade, and
this concept has attracted global attention. The notion of CSR has
strategic significance for many organizations. However, businesses
are not adapting the activities of CSR that benefit to all of its
stakeholders (including society). The main reason is the practitioners
are unfortunately unable to comprehend its importance; and
therefore, the activities of the CSR are so detached from the business
activities. Hence, it is required to develop an understanding that the
activities of CSR are not only beneficial for the society but it also
benefit to business. This paper focuses on the concept of strategic
CSR, and develops a theoretical framework that will help
practitioners to filter and chose the activities of CSR that are strategic
in nature.
Abstract: We have experimentally demonstrated bright-dark
pulses in a nonlinear polarization rotation (NPR) based mode-locked
Erbium-doped fiber laser (EDFL) with a long cavity configuration.
Bright–dark pulses could be achieved when the laser works in the
passively mode-locking regime and the net group velocity dispersion
is quite anomalous. The EDFL starts to generate a bright pulse train
with degenerated dark pulse at the mode-locking threshold pump
power of 35.09 mW by manipulating the polarization states of the
laser oscillation modes using a polarization controller (PC). A split
bright–dark pulse is generated when further increasing the pump
power up to 37.95 mW. Stable bright pulses with no obvious
evidence of a dark pulse can also be generated when further adjusting
PC and increasing the pump power up to 52.19 mW. At higher pump
power of 54.96 mW, a new form of bright-dark pulse emission was
successfully identified with the repetition rate of 29 kHz. The bright
and dark pulses have a duration of 795.5 ns and 640 ns, respectively.
Abstract: City shrinkage is one of the thorny problems that many
European cities have to face with nowadays. It is mainly expressed as
the decrease of population in these cities. Eastern Germany is one of
the pioneers of European shrinking cities with long shrinking history.
The paper selects one representative shrinking city Halle (Saale) in
eastern Germany as research objective, collecting and investigating
nearly 20 years (1993-2010) municipal data after the reunification of
Germany. These data based on five dimensions, which are
demographic, economic, social, spatial and environmental and total 16
eligible variables. Factor Analysis is used to deal with these variables
in order to assess the most important factors affecting shrinking Halle.
The results show that there are three main factors determine the
shrinkage of Halle, respectively named “demographical and
economical factor”, “social stability factor”, and “city vitality factor”.
The three factors act at different time period of Halle’s shrinkage: from
1993 to 1997 the demographical and economical factor played an
important role; from 1997 to 2004 the social stability factor is
significant to city shrinkage; since 2005 city vitality factor determines
the shrinkage of Halle. In recent years, the shrinkage in Halle mitigates
that shows the sign of growing population. Thus the city Halle should
focus on attaching more importance on the city vitality factor to
prevent the city from shrinkage. Meanwhile, the city should possess a
positive perspective to shift the growth-oriented development to tap
the potential of shrinking cities. This method is expected to apply to
further research and other shrinking cities
Abstract: The objective of this study was to determine effect of
dietary essential oil (EO) compounds, which contained
cinnamaldehyde, eugenol, peppermint, coriander, cumin, lemongrass,
and an organic carrier on feed intake, milk composition, and rumen
fermentation of dairy cows during heat exposure. Thirty-two Holstein
cows (days in milk= 60 ± 5) were assigned to one of two treatment
groups: a Control and EO fed. The experiment lasted 28 days. Dry
matter intake (DMI) was measured daily while and milk production
was measured weekly. Our result showed that DMI and milk yield
was decreased (P < 0.01) in control cows relative to EO cows.
Furthermore, supplementation with EO was associated with a
decrease in the molar proportion of propionate (P < 0.05) and
increase (P < 0.05) in acetate to propionate ratio. In conclusion, EO
supplementations in diets can be useful nutritional modification to
alleviate for the decrease DMI and milk production during heat
exposure in lactating dairy cows.
Abstract: In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.
Abstract: Domestic goats (Capra hircus) are extremely diverse
species and principal animal genetic resource of the developing
world. These facilitate a persistent supply of meat, milk, fibre, and
skin and are considered as important revenue generators in small
pastoral environments. This study aimed to fingerprint β-LG gene at
PCR-RFLP level in native Saudi goat breeds (Ardi, Habsi and Harri)
in an attempt to have a preliminary image of β-LG genotypic patterns
in Saudi breeds as compared to other foreign breeds such as Indian
and Egyptian. Also, the Phylogenetic analysis was done to investigate
evolutionary trends and similarities among the caprine β-LG gene
with that of the other domestic specie, viz. cow, buffalo and sheep.
Blood samples were collected from 300 animals (100 for each breed)
and genomic DNA was extracted. A fragment of the β-LG gene
(427bp) was amplified using specific primers. Subsequent digestion
with Sac II restriction endonuclease revealed two alleles (A and B)
and three different banding patterns or genotypes i.e. AA, AB and
BB. The statistical analysis showed a general trend that β-LG AA
genotype had higher milk yield than β-LG AB and β-LG BB
genotypes. Nucleotide sequencing of the selected β-LG fragments
was done and submitted to GenBank NCBI (Accession No.
KJ544248, KJ588275, KJ588276, KJ783455, KJ783456 and
KJ874959). Phylogenetic analysis on the basis of nucleotide
sequences of native Saudi goats indicated evolutional similarity with
the GenBank reference sequences of goat, Bubalus bubalis and Bos
taurus. However, the origin of sheep which is the most closely
related from the evolutionary point of view, was located some
distance away.
Abstract: The hydrogenated amorphous carbon films (α-C:H)
were deposited on p-type Si (100) substrates at different thicknesses by
radio frequency plasma enhanced chemical vapor deposition
technique (rf-PECVD). Raman spectra display asymmetric
diamond-like carbon (DLC) peaks, representative of the α-C:H films.
The decrease of intensity ID/IG ratios revealed the sp3 content arise at
different thicknesses of the α-C:H films. In terms of mechanical
properties, the high hardness and elastic modulus values showed the
elastic and plastic deformation behaviors related to sp3 content in
amorphous carbon films. Electrochemical properties showed that the
α-C:H films exhibited excellent corrosion resistance in air-saturated
3.5 wt.% NaCl solution for pH 2 at room temperature. Thickness
increasing affected the small sp2 clusters in matrix, restricting the
velocity transfer and exchange of electrons. The deposited α-C:H films
exhibited excellent mechanical properties and corrosion resistance.
Abstract: The Quad Tree Decomposition based performance
analysis of compressed image data communication for lossy and
lossless through wireless sensor network is presented. Images have
considerably higher storage requirement than text. While transmitting
a multimedia content there is chance of the packets being dropped
due to noise and interference. At the receiver end the packets that
carry valuable information might be damaged or lost due to noise,
interference and congestion. In order to avoid the valuable
information from being dropped various retransmission schemes have
been proposed. In this proposed scheme QTD is used. QTD is an
image segmentation method that divides the image into homogeneous
areas. In this proposed scheme involves analysis of parameters such
as compression ratio, peak signal to noise ratio, mean square error,
bits per pixel in compressed image and analysis of difficulties during
data packet communication in Wireless Sensor Networks. By
considering the above, this paper is to use the QTD to improve the
compression ratio as well as visual quality and the algorithm in
MATLAB 7.1 and NS2 Simulator software tool.
Abstract: In regards to the energy sector in the modern period,
two points were raised. First is a vast and growing energy demand, and
second is an environmental impact associated with it. The enormous
consumption of fossil fuel to the mobile unit is leading to its rapid
depletion. Nuclear power is not the only problem. A modal shift that
utilizes personal transporters and independent power, in order to
realize a sustainable society, is very effective. The author proposes that
the world will continue to work on this. Energy of the future society,
innovation in battery technology and the use of natural energy is a big
key. And it is also necessary in order to save on energy consumption.
Abstract: From a perspective of moral education, this study has
examined the experiences of a group of college students who
volunteered in disaster areas after the magnitude 9.0 Earthquake,
which struck the Northeastern region of Japan in March, 2011. The
research, utilizing the method of grounded theory, has uncovered that
most of the students have gone through positive changes in their
development of moral and social characters, such as attaining deeper
sense of empathy and caring personalities. The study expresses, in
identifying the nature of those transformations, that the importance of
volunteer work should strongly be recognized by the colleges and
universities in Japan, in fulfilling their public responsibility of creating
and building learning communities that are responsible and caring.
Abstract: Many studies have revealed the fact of the complexity
of ontology building process. Therefore there is a need for a new
approach which one of that addresses the socio-technical aspects in the
collaboration to reach a consensus. Meta-design approach is
considered applicable as a method in the methodological model of
socio-technical ontology engineering. Principles in the meta-design
framework are applied in the construction phases of the ontology. A
web portal is developed to support the meta-design principles
requirements. To validate the methodological model semantic web
applications were developed and integrated in the portal and also used
as a way to show the usefulness of the ontology. The knowledge based
system will be filled with data of Indonesian medicinal plants. By
showing the usefulness of the developed ontology in a semantic web
application, we motivate all stakeholders to participate in the
development of knowledge based system of medicinal plants in
Indonesia.
Abstract: Existing methods of data mining cannot be applied on
spatial data because they require spatial specificity consideration, as
spatial relationships.
This paper focuses on the classification with decision trees, which
are one of the data mining techniques. We propose an extension of
the C4.5 algorithm for spatial data, based on two different approaches
Join materialization and Querying on the fly the different tables.
Similar works have been done on these two main approaches, the
first - Join materialization - favors the processing time in spite of
memory space, whereas the second - Querying on the fly different
tables- promotes memory space despite of the processing time.
The modified C4.5 algorithm requires three entries tables: a target
table, a neighbor table, and a spatial index join that contains the
possible spatial relationship among the objects in the target table and
those in the neighbor table. Thus, the proposed algorithms are applied
to a spatial data pattern in the accidentology domain.
A comparative study of our approach with other works of
classification by spatial decision trees will be detailed.
Abstract: This work is focused on the study of valuation of
recycled concrete aggregates, by measuring certain properties of
concrete in the fresh and hardened state. In this study, rheological
tests and physic-mechanical characterization on concretes and
mortars were conducted with recycled concrete whose geometric
properties were identified aggregates. Mortars were elaborated with
recycled fine aggregate (0/5mm) and concretes were manufactured
using recycled coarse aggregates (5/12.5 mm and 12.5/20 mm). First,
a study of the mortars was conducted to determine the effectiveness
of polycarboxylate superplasticizer on the workability of these and
their action deflocculating of the recycled sand. The rheological
behavior of mortars based on fine aggregate recycled was
characterized. The results confirm that the mortars composed of
different fractions of recycled sand (0 /5) have a better mechanical
properties (compressive and flexural strength) compared to normal
mortar. Also, the mechanical strengths of concretes made with
recycled aggregates (5/12.5 mm and 12.5/20 mm), are comparable to
those of conventional concrete with conventional aggregates,
provided that the implementation can be improved by the addition of
a superplasticizer.
Abstract: This review summarizes the potential of starch
agroindustrial residues as substrate for biohydrogen production.
Types of potential starch agroindustrial residues, recent developments
and bio-processing conditions for biohydrogen production will be
discussed. Biohydrogen is a clean energy source with great potential
to be an alternative fuel, because it releases energy explosively in
heat engines or generates electricity in fuel cells producing water as
only by-product. Anaerobic hydrogen fermentation or dark
fermentation seems to be more favorable, since hydrogen is yielded
at high rates and various organic waste enriched with carbohydrates
as substrate result in low cost for hydrogen production. Abundant
biomass from various industries could be source for biohydrogen
production where combination of waste treatment and energy
production would be an advantage. Carbohydrate-rich nitrogendeficient
solid wastes such as starch residues can be used for
hydrogen production by using suitable bioprocess technologies.
Alternatively, converting biomass into gaseous fuels, such as
biohydrogen is possibly the most efficient way to use these
agroindustrial residues.