Abstract: Many studies have emphasized the importance of
resistive exercise to maintain a healthy human body, particular in
prevention of weakening of physical strength. Recently, some studies
advocated that an application of vibration as a supplementary means in
a regular training was effective in encouraging physical strength. Aim
of the current study was, therefore, to identify if an application of
vibration in a resistive exercise was effective in encouraging physical
strength as that in a regular training. A 3-dimensional virtual lower
extremity model for a healthy male and virtual leg-press model were
generated and synchronized. Dynamic leg-press exercises on a slide
machine with/without extra load and on a footboard with vibration as
well as on a slide machine with extra load were analyzed. The results
of the current indicated that the application of the vibration on the
dynamic leg-press exercise might be not greatly effective in
encouraging physical strength, compared with the dynamic leg press
exercise with extra load. It was, however, thought that the application
of the vibration might be helpful to elderly individuals because the
reduced maximum muscle strength appeared by the effect of the
vibration may avoid a muscular spasm, which can be driven from a
high muscle strength sometimes produced during the leg-press
exercise with extra load.
Abstract: In this paper we propose a class of second derivative multistep methods for solving some well-known classes of Lane- Emden type equations which are nonlinear ordinary differential equations on the semi-infinite domain. These methods, which have good stability and accuracy properties, are useful in deal with stiff ODEs. We show superiority of these methods by applying them on the some famous Lane-Emden type equations.
Abstract: Particulate reinforced metal matrix composites
(MMCs) are potential materials for various applications due to their
advantageous of physical and mechanical properties. This paper
presents a study on the performance of stir cast Al2O3 SiC reinforced
metal matrix composite materials. The results indicate that the
composite materials exhibit improved physical and mechanical
properties, such as, low coefficient of thermal expansion, high
ultimate tensile strength, high impact strength, and hardness. It has
been found that with the increase of weight percentage of
reinforcement particles in the aluminium metal matrix, the new
material exhibits lower wear rate against abrasive wearing. Being
extremely lighter than the conventional gray cast iron material, the
Al-Al2O3 and Al-SiC composites could be potential green materials
for applications in the automobile industry, for instance, in making
car disc brake rotors.
Abstract: This paper presents an efficient algorithm for
optimization of radial distribution systems by a network
reconfiguration to balance feeder loads and eliminate overload
conditions. The system load-balancing index is used to determine the
loading conditions of the system and maximum system loading
capacity. The index value has to be minimum in the optimal network
reconfiguration of load balancing. A method based on Tabu search
algorithm, The Tabu search algorithm is employed to search for the
optimal network reconfiguration. The basic idea behind the search is
a move from a current solution to its neighborhood by effectively
utilizing a memory to provide an efficient search for optimality. It
presents low computational effort and is able to find good quality
configurations. Simulation results for a radial 69-bus system with
distributed generations and capacitors placement. The study results
show that the optimal on/off patterns of the switches can be identified
to give the best network reconfiguration involving balancing of
feeder loads while respecting all the constraints.
Abstract: Developments in communication technologies
especially in wireless have enabled the progress of low-cost and lowpower
wireless sensor networks (WSNs). The features of such WSN
are holding minimal energy, weak computational capabilities,
wireless communication and an open-medium nature where sensors
are deployed. WSN is underpinned by application driven such as
military applications, the health sector, etc. Due to the intrinsic nature
of the network and application scenario, WSNs are vulnerable to
many attacks externally and internally. In this paper we have focused
on the types of internal attacks of WSNs based on OSI model and
discussed some security requirements, characterizers and challenges
of WSNs, by which to contribute to the WSN-s security research.
Abstract: The present work deals with the structural analysis of
turbine blades and modeling of turbine blades. A common failure
mode for turbine machines is high cycle of fatigue of compressor and
turbine blades due to high dynamic stresses caused by blade vibration
and resonance within the operation range of the machinery. In this
work, proper damping system will be analyzed to reduce the
vibrating blade. The main focus of the work is the modeling of under
platform damper to evaluate the dynamic analysis of turbine-blade
vibrations. The system is analyzed using Bond graph technique. Bond
graph is one of the most convenient ways to represent a system from
the physical aspect in foreground. It has advantage of putting together
multi-energy domains of a system in a single representation in a
unified manner. The bond graph model of dry friction damper is
simulated on SYMBOLS-shakti® software. In this work, the blades
are modeled as Timoshenko beam. Blade Vibrations under different
working conditions are being analyzed numerically.
Abstract: TiO2 nanoparticles were synthesized by hydrothermal
method at 180°C from TiOSO4 aqueous solution with1m/l
concentration. The obtained products were coated with silica by
means of a seeded polymerization technique for a coating time of
1440 minutes to obtain well defined TiO2@SiO2 core-shell structure.
The uncoated and coated nanoparticles were characterized by using
X-Ray diffraction technique (XRD), Fourier Transform Infrared
Spectroscopy (FT-IR) to study their physico-chemical properties.
Evidence from XRD and FTIR results show that SiO2 is
homogenously coated on the surface of titania particles. FTIR spectra
show that there exists an interaction between TiO2 and SiO2 and
results in the formation of Ti-O-Si chemical bonds at the interface of
TiO2 particles and SiO2 coating layer. The non linear optical limiting
properties of TiO2 and TiO2@SiO2 nanoparticles dispersed in
ethylene glycol were studied at 532nm using 5ns Nd:YAG laser
pulses. Three-photon absorption is responsible for optical limiting
characteristics in these nanoparticles and it is seen that the optical
nonlinearity is enhanced in core-shell structures when compared with
single counterparts. This effective three-photon type absorption at
this wavelength, is of potential application in fabricating optical
limiting devices.
Abstract: The degradation of selected pharmaceuticals in some
water matrices was studied by using several chemical treatments. The
pharmaceuticals selected were the beta-blocker metoprolol, the
nonsteroidal anti-inflammatory naproxen, the antibiotic amoxicillin,
and the analgesic phenacetin; and their degradations were conducted
by using UV radiation alone, ozone, Fenton-s reagent, Fenton-like
system, photo-Fenton system, and combinations of UV radiation and
ozone with H2O2, TiO2, Fe(II), and Fe(III). The water matrices, in
addition to ultra-pure water, were a reservoir water, a groundwater,
and two secondary effluents from two municipal WWTP. The results
reveal that the presence of any second oxidant enhanced the
oxidation rates, with the systems UV/TiO2 and O3/TiO2 providing the
highest degradation rates. It is also observed in most of the
investigated oxidation systems that the degradation rate followed the
sequence: amoxicillin > naproxen > metoprolol > phenacetin. Lower
rates were obtained with the pharmaceuticals dissolved in natural
waters and secondary effluents due to the organic matter present
which consume some amounts of the oxidant agents.
Abstract: Megalopolis is a group of densely populated metropolitan areas that combine to form an urban complex. Since China introduced the economic reforms in late 1970s, the Chinese urban system has experienced unprecedented growth. The process of urbanisation prevailed in the 1980s, and the process of predominantly large city growth appeared to continue through 1990s and 2000s. In this study, the magnitude and pattern of urbanisation in China during 1990s were examined using remotely sensed imagery acquired by TM/ETM+ sensor onboard the Landsat satellites. The development of megalopolis areas in China was also studied based on the GIS analysis of the increases of urban and built-up area from 1990 to 2000. The analysis suggests that in the traditional agricultural zones in China, e.g., Huang-Huai-Hai Plains, Changjiang River Delta, Pearl River Delta and Sichuan Basin, the urban and built-up areas increased by 1.76 million hectares, of which 0.82 million hectares are expansion of urban areas, an increase of 24.78% compared with 1990 at the national scale. The Yellow River Delta, Changjiang River Delta and Pearl River Delta also saw an increase of urban and built-up area by 63.9%, 66.2% and 83.0% respectively. As a result, three major megalopolises were developed in China: the Guangzhou-Shenzhen-Hong Kong- Macau (Pearl River Delta: PRD) megalopolis area, the Shanghai- Nanjing-Hangzhou (Changjiang River Delta: CRD) megalopolis area and the Beijing-Tianjing-Tangshan-Qinhuangdao (Yellow River Delta-Bohai Sea Ring: YRD) megalopolis area. The relationship between the processed of megalopolisation and the inter-provincial population flow was also explored in the context of social-economic and transport infrastructure development in Post-reform China.
Abstract: The present article deals with a composite casting process that allows to produce bilayer AlSn6-Al strips based on the technique of horizontal continuous casting. In the first part experimental investigations on the production of a single layer AlSn6 strip are described. Afterwards essential results of basic compound casting trials using simple test specimen are presented to define the thermal conditions required for a metallurgical compound between the alloy AlSn6 and pure aluminium. Subsequently, numerical analyses are described. A finite element model was used to examine a continuous composite casting process. As a result of the simulations the main influencing parameters concerning the thermal conditions within the composite casting region could be pointed out. Finally, basic guidance is given for the design of an appropriate composite mould system.
Abstract: detecting the deadlock is one of the important
problems in distributed systems and different solutions have been
proposed for it. Among the many deadlock detection algorithms,
Edge-chasing has been the most widely used. In Edge-chasing
algorithm, a special message called probe is made and sent along
dependency edges. When the initiator of a probe receives the probe
back the existence of a deadlock is revealed. But these algorithms are
not problem-free. One of the problems associated with them is that
they cannot detect some deadlocks and they even identify false
deadlocks. A key point not mentioned in the literature is that when
the process is waiting to obtain the required resources and its
execution has been blocked, how it can actually respond to probe
messages in the system. Also the question of 'which process should
be victimized in order to achieve a better performance when multiple
cycles exist within one single process in the system' has received
little attention. In this paper, one of the basic concepts of the
operating system - daemon - will be used to solve the problems
mentioned. The proposed Algorithm becomes engaged in sending
probe messages to the mandatory daemons and collects enough
information to effectively identify and resolve multi-cycle deadlocks
in distributed systems.
Abstract: The aspiration of this research article is to target and
focus the gains of university-Industry (U-I) collaborations and
exploring those hurdles which are the obstacles for attaining these
gains. University-Industry collaborations have attained great
importance since 1980 in USA due to its application in all fields of
life. U-I collaboration is a bilateral process where academia is a
proactive member to make such alliances. Universities want to
ameliorate their academic-base with the technicalities of technobabbles.
U-I collaboration is becoming an essential lane for achieving
innovative goals in this century. Many developed nations have set
successful examples to prove this phenomenon as a catalyst to reduce
costs, efforts and personnel for R&D projects. This study is exploits
amplitudes of UI collaboration incentives in the light of success
stories of developed countries. Many universities in USA, UK,
Canada and various European Countries have been engaged with
enterprises for numerous collaborative agreements. A long list of
strategic and short term R&D projects has been executed in
developed countries to accomplish their intended purposes. Due to
the lack of intentions, genuine research and research-oriented
environment, the mentioned field could not grow very well in
developing countries. During last decade, a new wave of research
has induced the institutes of developing countries to promote R&D
culture especially in Pakistan. Higher Education Commission (HEC)
has initiated many projects and funding supports for universities
which have collaborative intentions with industry.
Findings show that rapid innovation, overwhelm the technological
complexities and articulated intellectual-base are major incentives
which steer both partners to establish faculty-industry alliances. Everchanging
technologies, concerned about intellectual property,
different research environment and culture, research relevancy (Basic
or applied), exposure differences and diversity of knowledge
(bookish or practical) are main barriers to establish and retain joint
ventures. Findings also concluded that, it is dire need to support and
enhance cooperation among academia and industry to promote highly
coordinated research behaviors. Author has proposed a roadmap for
developing countries to promote R&D clusters among faculty and
industry to deal the technological challenges and innovation
complexities. Based on our research findings, Model for R&D
Collaboration for developing countries also have been proposed to
promote articulated R&D environment. If developing countries
follow this phenomenon, rapid innovations can be achieved with
limited R&D budget heads.
Abstract: Data mining techniques have been used in medical
research for many years and have been known to be effective. In order
to solve such problems as long-waiting time, congestion, and delayed
patient care, faced by emergency departments, this study concentrates
on building a hybrid methodology, combining data mining techniques
such as association rules and classification trees. The methodology is
applied to real-world emergency data collected from a hospital and is
evaluated by comparing with other techniques. The methodology is
expected to help physicians to make a faster and more accurate
classification of chest pain diseases.
Abstract: The aim of current research was to investigate ASLT method suitability for accelerated beer shelf-life determination. The research was accomplished on popular Latvian beer: light filtrated and unfiltered pasteurized beer with alcohol content 5.2%; dark filtrated pasteurized beer with alcohol content 4.2% with shelf-life five months. Bottled in dark glass bottles beer samples were storage during 20 weeks at several temperature regimes: +10±1 °C, +20±1 °C, +30±1 °C, +40±1 °C. Samples quality parameters as physically-chemical and microbiological was tested every two weeks using standard methods. It is possible to determine beer shelf-life rapidly during storage at +30±1 °C for filtered pasteurized light beer by 2.5 times, unfiltered pasteurized light beer by 1.4 times and for filtered pasteurized dark beer by 1.7 times. During preset experiments it was proved, that it is possible to determine beer shelf-life rapidly using ASLT method if beer storage temperature could be increased by +10±1 °C.
Abstract: This paper presents a physics-based model for the
high-voltage fast recovery diodes. The model provides a good
trade-off between reverse recovery time and forward voltage drop
realized through a combination of lifetime control and emitter
efficiency reduction techniques. The minority carrier lifetime can be
extracted from the reverse recovery transient response and forward
characteristics. This paper also shows that decreasing the amount of
the excess carriers stored in the drift region will result in softer
characteristics which can be achieved using a lower doping level. The
developed model is verified by experiment and the measurement data
agrees well with the model.
Abstract: Cements, which are intrinsically brittle materials, can
exhibit a degree of pseudo-ductility when reinforced with a sufficient
volume fraction of a fibrous phase. This class of materials, called
Engineered Cement Composites (ECC) has the potential to be used in
future tunneling applications where a level of pseudo-ductility is
required to avoid brittle failures. However uncertainties remain
regarding mechanical performance. Previous work has focused on
comparatively thin specimens; however for future civil engineering
applications, it is imperative that the behavior in tension of thicker
specimens is understood. In the present work, specimens containing
cement powder and admixtures have been manufactured following
two different processes and tested in tension. Multiple matrix
cracking has been observed during tensile testing, leading to a
“strain-hardening" behavior, confirming the possible suitability of
ECC material when used as thick sections (greater than 50mm) in
tunneling applications.
Abstract: We intend to point out the differences which exist
between the classical Gini concentration coefficient and a proposed
bipolarization index defined for an arbitrary random variable which
have a finite support.
In fact Gini's index measures only the "poverty degree" for the
individuals from a given population taking into consideration their
wages. The Gini coefficient is not so sensitive to the significant
income variations in the "rich people class" .
In practice there are multiple interdependent relations between the
pauperization and the socio-economical polarization phenomena. The
presence of a strong pauperization aspect inside the population
induces often a polarization effect in this society. But the
pauperization and the polarization phenomena are not identical. For
this reason it isn't always adequate to use a Gini type coefficient,
based on the Lorenz order, to estimate the bipolarization level of the
individuals from the studied population.
The present paper emphasizes these ideas by considering two
families of random variables which have a linear or a triangular type
distributions. In addition, the continuous variation, depending on the
parameter "time" of the chosen distributions, could simulate a real
dynamical evolution of the population.
Abstract: Desert regions around the Nile valley in Upper Egypt
contain great extent of swelling soil. Many different comment
procedures of treatment of the swelling soils for construction such as
pre-swelling, load balance OR soil replacement. One of the measure
factors which affect the level of the aggressiveness of the swelling
soil is the direction of the infiltration water directions within the
swelling soils. In this paper a physical model was installed to
measure the effect of water on the swelling soil with replacement
using fatty acid distillation residuals (FADR) mixed with sand as
thick sand-FADR mixture to prevent the water pathway arrive to the
swelling soil. Testing program have been conducted on different
artificial samples with different sand to FADR contents ratios (4%,
6%, and 9%) to get the optimum value fulfilling the impermeable
replacement. The tests show that a FADR content of 9% is sufficient
to produce impermeable replacement.
Abstract: There are a many of needs for the development of
SiC-based hydrogen sensor for harsh environment applications. We
fabricated and investigated Pd/Ta2O5/SiC-based hydrogen sensors
with MOS capacitor structure for high temperature process monitoring
and leak detection applications in such automotive, chemical and
petroleum industries as well as direct monitoring of combustion
processes. In this work, we used silicon carbide (SiC) as a substrate to
replace silicon which operating temperatures are limited to below
200°C. Tantalum oxide was investigated as dielectric layer which has
high permeability for hydrogen gas and high dielectric permittivity,
compared with silicon dioxide or silicon nitride. Then, electrical
response properties, such as I-V curve and dependence of capacitance
on hydrogen concentrations were analyzed in the temperature ranges
of room temperature to 500°C for performance evaluation of the
sensor.
Abstract: Manufacturing companies are facing a broad variety
of challenges caused by a dynamic production environment. To
succeed in such an environment, it is crucial to minimize the loss of
time required to trigger the adaptation process of a company-s
production structures. This paper presents an approach for the
continuous monitoring of production structures by neurologic
principles. It enhances classical monitoring concepts, which are
principally focused on reactive strategies, and enables companies to
act proactively. Thereby, strategic aspects regarding the
harmonization of certain life cycles are integrated into the decision
making process for triggering the reconfiguration process of the
production structure.