Abstract: A solar powered air heating system using one ended evacuated tubes is experimentally investigated. A solar air heater containing forty evacuated tubes is used for heating purpose. The collector surface area is about 4.44 m2. The length and outer diameters of the outer glass tube and absorber tube are 1500, 47 and 37 mm, respectively. In this experimental setup, we have a header (heat exchanger) of square shape (190 mm x 190 mm). The length of header is 1500 mm. The header consists of a hollow pipe in the center whose diameter is 60 mm through which the air is made to flow. The experimental setup contains approximately 108 liters of water. Water is working as heat collecting medium which collects the solar heat falling on the tubes. This heat is delivered to the air flowing through the header pipe. This heat flow is due to natural convection and conduction. The outlet air temperature depends upon several factors along with air flow rate and solar radiation intensity. The study has been done for both up-flow and down-flow of air in header in similar weather conditions, at different flow rates. In the present investigations the study has been made to find the effect of intensity of solar radiations and flow rate of air on the out let temperature of the air with time and which flow is more efficient. The obtained results show that the system is highly effective for the heating in this region. Moreover, it has been observed that system is highly efficient for the particular flow rate of air. It was also observed that downflow configuration is more effective than up-flow condition at all flow rates due to lesser losses in down-flow. The results show that temperature differences of upper head and lower head, both of water and surface of pipes on the respective ends is lower in down-flow.
Abstract: Nowadays, the importance of energy saving is clearance to everyone. By attention to increasing price of fuels and also the problems of environment pollutions, there are the most efforts for using fuels littler and more optimum in everywhere. This essay studies optimizing of gas consumption in gas-burner space heaters. In oven of each gas-burner space heaters there is two snags to prevent the hot air (the result of combustion of natural gas) to go out of oven of the gas-burner space heaters directly without delivering its heat to the space of favorite environment like a room. These snags cause a excess circulating that helps hot air deliver its heat to the space of favorite environment. It means the exhaust air temperature will be decreased then when there are no snags. This is the aim of this essay to use maximum potential energy of the natural gas to make heat. In this study, by the help of a finite volume software (FLUENT) consumption of the gas-burner space heaters is simulated and optimized. At the end of this writing, by comparing the results of software and experimental results, it will be proved the authenticity of this method.
Abstract: Using strength Pulse Electrical Field (PEF) in food
industries is a non-thermal process that can deactivate
microorganisms and increase penetration in plant and animals tissues
without serious impact on food taste and quality. In this paper designing and fabricating of a PEF generator has been presented. Pulse generation methods have been surveyed and the best of them
selected. The equipment by controller set can generate square pulse with adjustable parameters such as amplitude 1-5kV, frequency 0.1-10Hz, pulse width 10-100s, and duty cycle 0-100%. Setting the number of pulses, and presenting the output voltage and current
waveforms on the oscilloscope screen are another advantages of this
equipment. Finally, some food samples were tested that yielded the satisfactory results. PEF applying had considerable effects on potato, banana and purple cabbage. It caused increase Brix factor from 0.05
to 0.15 in potato solution. It is also so effective in extraction color material from purple cabbage. In the last experiment effects of PEF
voltages on color extraction of saffron scum were surveyed (about 6% increasing yield).
Abstract: The construction of original functional sample of the portable device for fast analysis of energetic materials has been described in the paper. The portable device consisting of two parts – an original miniaturized microcolumn liquid chromatograph and a unique chemiluminescence detector – has been proposed and realized. In a very short time, this portable device is capable of identifying selectively most of military nitramine- and nitroesterbased explosives as well as inorganic nitrates occurring in trace concentrations in water or in soil. The total time required for the identification of extracts is shorter than 8 minutes.
Abstract: This paper analyzes the effect of a single uniform accounting rule on reporting quality by investigating the influence of IFRS on earnings management. This paper examines whether earnings management is reduced after IFRS adoption through the use of “loss avoidance thresholds”, a method that has been verified in earlier studies. This paper concentrates on two European countries: one that represents the continental code law tradition with weak protection of investors (France) and one that represents the Anglo-American common law tradition, which typically implies a strong enforcement system (the United Kingdom).
The research investigates a sample of 526 companies (6822 firm-year observations) during the years 2000 – 2013. The results are different for the two jurisdictions. This study demonstrates that a single set of accounting standards contributes to better reporting quality and reduces the pervasiveness of earnings management in France. In contrast, there is no evidence that a reduction in earnings management followed the implementation of IFRS in the United Kingdom. Due to the fact that IFRS benefit France but not the United Kingdom, other political and economic factors, such legal system or capital market strength, must play a significant role in influencing the comparability and transparency cross-border companies’ financial statements. Overall, the result suggests that IFRS moderately contribute to the accounting quality of reported financial statements and bring benefit for stakeholders, though the role played by other economic factors cannot be discounted.
Abstract: The morphological short-term evolution of Ponta do Tubarão Island (PTI) was investigated through high accurate surveys based on post-processed kinematic (PPK) relative positioning on Global Navigation Satellite Systems (GNSS). PTI is part of a barrier island system on a high energy northeast Brazilian coastal environment and also an area of high environmental sensitivity. Surveys were carried out quarterly over a two years period from May 2010 to May 2012. This paper assesses statically the performance of digital elevation models (DEM) derived from different interpolation methods to represent morphologic features and to quantify volumetric changes and TIN models shown the best results to that purposes. The MDE allowed quantifying surfaces and volumes in detail as well as identifying the most vulnerable segments of the PTI to erosion and/or accumulation of sediments and relate the alterations to climate conditions. The coastal setting and geometry of PTI protects a significant mangrove ecosystem and some oil and gas facilities installed in the vicinities from damaging effects of strong oceanwaves and currents. Thus, the maintenance of PTI is extremely required but the prediction of its longevity is uncertain because results indicate an irregularity of sedimentary balance and a substantial decline in sediment supply to this coastal area.
Abstract: In this work, the effects of scale on thermal behavior of the slab in a walking-beam type reheating furnace is studied by considering scale formation and growth in a furnace environment. Also, mathematical heat transfer model to predict the thermal radiation in a complex shaped reheating furnace with slab and skid buttons is developed with combined nongray WSGGM and blocked-off solution procedure. The model can attack the heat flux distribution within the furnace and the temperature distribution in the slab throughout the reheating furnace process by considering the heat exchange between the slab and its surroundings, including the radiant heat transfer among the slabs, the skids, the hot combustion gases and the furnace wall as well as the gas convective heat transfer in the furnace. With the introduction of the mathematical formulations validation of the present numerical model is conducted by calculating two example problems of blocked-off and nongray gas radiative heat transfer. After discussing the formation and growth of the scale on the slab surface, slab heating characteristics with scale is investigated in terms of temperature rise with time.
Abstract: Service life of existing reinforced concrete (RC)
structures in coastal towns of Sabah has been affected very much.
Concrete crack, spalling of concrete cover and reinforcement rusting
of RC buildings are seen even within 5 years of construction in
Sabah. Hence, in this study a new mix design of concrete grout was
developed using locally available materials and investigated under
two curing conditions and workability, compressive strength,
Accelerated Mortar Bar Test (AMBT), water absorption, volume of
permeable voids (VPV), Sorptivity and 90-days salt ponding test
were conducted. The compressive strength of concrete grout at the
age 90 days was found to be 44.49 N/mm2 under water curing. It was
observed that the percentage of mortar bar length change was below
1% for developed concrete grout. The water absorption of the
concrete grout was in between the range of 0.88 % to 3.60 % under
two different curing up to the age 90 days. It was also observed that
the VPV of concrete was in the range of 0 % to 9.75 and 2.44% to
13.05% under water curing and site curing respectively. It was found
that the Sorptivity of the concrete grout under water curing at the age
of 28 days is 0.211mm/√min and at the age 90 day are 0.067
mm/√min. The chloride content decreased greatly, 90% after a depth
of 15 mm. It was noticed that the site cured samples showed higher
chloride contents near surface compared to water cured samples.
This investigation suggested that the developed mix design of
concrete grout using locally available construction materials can be
used for crack repairing of existing RC structures in Sabah.
Abstract: The complex shape of the human pelvic bone was
successfully imaged and modeled using finite element FE processing.
The bone was subjected to quasi-static and dynamic loading
conditions simulating the effect of both weight gain and impact.
Loads varying between 500 – 2500 N (~50 – 250 Kg of weight) was
used to simulate 3D quasi-static weight gain. Two different 3D
dynamic analyses, body free fall at two different heights (1 and 2 m)
and forced side impact at two different velocities (20 and 40 Km/hr)
were also studied. The computed resulted stresses were compared for
the four loading cases, where Von Misses stresses increases linearly
with the weight gain increase under quasi-static loading. For the
dynamic models, the Von Misses stress history behaviors were
studied for the affected area and effected load with respect to time.
The normalization Von Misses stresses with respect to the applied
load were used for comparing the free fall and the forced impact load
results. It was found that under the forced impact loading condition
an over lapping behavior was noticed, where as for the free fall the
normalized Von Misses stresses behavior was found to nonlinearly
different. This phenomenon was explained through the energy
dissipation concept. This study will help designers in different
specialization in defining the weakest spots for designing different
supporting systems.
Abstract: The alternative technique for sterilization of culture
medium to replace autoclaving was carried out. For sterilization of
culture medium without autoclaving, some commercial pure essential
oils, bergamot oil, betel oil, cinnamon oil, lavender oil and turmeric
oil, were tested alone or in combinations with some disinfectants,
10% povidone-iodine and 2% iodine + 2.4% potassium iodide. Each
essential oil or combination was added to 25-mL Murashige and
Skoog (MS) medium before medium was solidified in a 120-mL
container, kept for 2 weeks before evaluating sterile conditions.
Treated media, supplemented with essential oils, were compared to
control medium, autoclaved at 121 degree Celsius for 15 min. In
vitro sterile conditions were found 20 – 100% from these treated
media compared to 100% sterile condition from autoclaved medium.
Treated media obtained 100% sterile conditions were chosen for
culturing chrysanthemum shoots. It was found that 10% povidoneiodine
in combination with cinnamon oil (3:1) and 2% iodine + 2.4%
potassium iodide in combination with lavender oil (1:3) at the
concentration of 36 3L/25 mL medium provided the promising
growth of shoot explants.
Abstract: Cryo-electron microscopy (CEM) in combination with
single particle analysis (SPA) is a widely used technique for
elucidating structural details of macromolecular assemblies at closeto-
atomic resolutions. However, development of automated software
for SPA processing is still vital since thousands to millions of
individual particle images need to be processed. Here, we present our
workflow for automated particle picking. Our approach integrates
peak shape analysis to the classical correlation and an iterative
approach to separate macromolecules and background by
classification. This particle selection workflow furthermore provides
a robust means for SPA with little user interaction. Processing
simulated and experimental data assesses performance of the
presented tools.
Abstract: Efficient storage, transmission and use of video information are key requirements in many multimedia applications currently being addressed by MPEG-4. To fulfill these requirements, a new approach for representing video information which relies on an object-based representation, has been adopted. Therefore, objectbased watermarking schemes are needed for copyright protection. This paper proposes a novel blind object watermarking scheme for images and video using the in place lifting shape adaptive-discrete wavelet transform (SA-DWT). In order to make the watermark robust and transparent, the watermark is embedded in the average of wavelet blocks using the visual model based on the human visual system. Wavelet coefficients n least significant bits (LSBs) are adjusted in concert with the average. Simulation results shows that the proposed watermarking scheme is perceptually invisible and robust against many attacks such as lossy image/video compression (e.g. JPEG, JPEG2000 and MPEG-4), scaling, adding noise, filtering, etc.
Abstract: Spam mails are unwanted mails sent to large number
of users. Spam mails not only consume the network resources, but
cause security threats as well. This paper proposes an efficient
technique to detect, and to prevent spam mail in the sender side rather
than the receiver side. This technique is based on a counter set on the
sender server. When a mail is transmitted to the server, the mail server
checks the number of the recipients based on its counter policy. The
counter policy performed by the mail server is based on some
pre-defined criteria. When the number of recipients exceeds the
counter policy, the mail server discontinues the rest of the process, and
sends a failure mail to sender of the mail; otherwise the mail is
transmitted through the network. By using this technique, the usage of
network resources such as bandwidth, and memory is preserved. The
simulation results in real network show that when the counter is set on
the sender side, the time required for spam mail detection is 100 times
faster than the time the counter is set on the receiver side, and the
network resources are preserved largely compared with other
anti-spam mail techniques in the receiver side.
Abstract: Mobile agents are a powerful approach to develop distributed systems since they migrate to hosts on which they have the resources to execute individual tasks. In a dynamic environment like a peer-to-peer network, Agents have to be generated frequently and dispatched to the network. Thus they will certainly consume a certain amount of bandwidth of each link in the network if there are too many agents migration through one or several links at the same time, they will introduce too much transferring overhead to the links eventually, these links will be busy and indirectly block the network traffic, therefore, there is a need of developing routing algorithms that consider about traffic load. In this paper we seek to create cooperation between a probabilistic manner according to the quality measure of the network traffic situation and the agent's migration decision making to the next hop based on decision tree learning algorithms.
Abstract: The past decade has seen enormous growth in the amount of software produced. However, given the ever increasing complexity of the software being developed and the concomitant rise in the typical project size, managers are becoming increasingly aware of the importance of issues that influence the productivity levels of the project teams involved. By analyzing the latest release of ISBSG data repository, we report on the factors found to significantly influence the productivity among which average team size and language type are the two most essential ones. Building on this we present an original model for evaluating the potential productivity during the project planning stage.
Abstract: Does a communication modality matter in delivering e-learning information? With the recent growth of broadcasting systems, media technologies and e-learning contents, various systems with different communication modalities have been introduced. In accordance with these trends, this study examines the effects of the information delivery modality on psychology of students. Findings from an experiment indicated that the delivering information which includes a video modality elicited higher degrees of credibility, quality, representativeness of content, and perceived suitability for delivering information than those of auditory information. However, there is no difference between content liking and attitude. The Implications of the findings and the limitations are discussed.
Abstract: IPsec has now become a standard information security
technology throughout the Internet society. It provides a well-defined
architecture that takes into account confidentiality, authentication,
integrity, secure key exchange and protection mechanism against
replay attack also. For the connectionless security services on packet
basis, IETF IPsec Working Group has standardized two extension
headers (AH&ESP), key exchange and authentication protocols. It is
also working on lightweight key exchange protocol and MIB's for
security management. IPsec technology has been implemented on
various platforms in IPv4 and IPv6, gradually replacing old
application-specific security mechanisms. IPv4 and IPv6 are not
directly compatible, so programs and systems designed to one
standard can not communicate with those designed to the other. We
propose the design and implementation of controlled Internet security
system, which is IPsec-based Internet information security system in
IPv4/IPv6 network and also we show the data of performance
measurement. With the features like improved scalability and
routing, security, ease-of-configuration, and higher performance of
IPv6, the controlled Internet security system provides consistent
security policy and integrated security management on IPsec-based
Internet security system.
Abstract: Nonlinear and unbalance loads in three phase
networks create harmonics and losses. Active and passive filters are
used for elimination or reduction of these effects. Passive filters have
some limitations. For example, they are designed only for a specific
frequency and they may cause to resonance in the network at the
point of common coupling. The other drawback of a passive filter is
that the sizes of required elements are normally large. The active
filter can improve some of limitations of passive filter for example;
they can eliminate more than one harmonic and don't cause resonance
in the network. In this paper inverter analysis have been done
simultaneously in three phase and the RL impedance of the line have
been considered. A sliding mode control based on energy feedback of
capacitors is employed in the design with this method, the dynamic
speed of the filter is improved effectively and harmonics and load
unbalance is compensating quickly.
Abstract: Clustering categorical data is more complicated than
the numerical clustering because of its special properties. Scalability
and memory constraint is the challenging problem in clustering large
data set. This paper presents an incremental algorithm to cluster the
categorical data. Frequencies of attribute values contribute much in
clustering similar categorical objects. In this paper we propose new
similarity measures based on the frequencies of attribute values and
its cardinalities. The proposed measures and the algorithm are
experimented with the data sets from UCI data repository. Results
prove that the proposed method generates better clusters than the
existing one.
Abstract: An important structuring mechanism for knowledge bases is building clusters based on the content of their knowledge objects. The objects are clustered based on the principle of maximizing the intraclass similarity and minimizing the interclass similarity. Clustering can also facilitate taxonomy formation, that is, the organization of observations into a hierarchy of classes that group similar events together. Hierarchical representation allows us to easily manage the complexity of knowledge, to view the knowledge at different levels of details, and to focus our attention on the interesting aspects only. One of such efficient and easy to understand systems is Hierarchical Production rule (HPRs) system. A HPR, a standard production rule augmented with generality and specificity information, is of the following form Decision If < condition> Generality Specificity . HPRs systems are capable of handling taxonomical structures inherent in the knowledge about the real world. In this paper, a set of related HPRs is called a cluster and is represented by a HPR-tree. This paper discusses an algorithm based on cumulative learning scenario for dynamic structuring of clusters. The proposed scheme incrementally incorporates new knowledge into the set of clusters from the previous episodes and also maintains summary of clusters as Synopsis to be used in the future episodes. Examples are given to demonstrate the behaviour of the proposed scheme. The suggested incremental structuring of clusters would be useful in mining data streams.