Search results for: Hidden Markov chain with a bi-dimensional observed process
Commenced in January 2007
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Edition: International
Paper Count: 7593

Search results for: Hidden Markov chain with a bi-dimensional observed process

4473 Motor Imagery Based Brain-Computer Interface for Cerebellar Impaired Patients

Authors: Young-Seok Choi

Abstract:

Cerebellar ataxia is a steadily progressive neurodegenerative disease associated with loss of motor control, leaving patients unable to walk, talk, or perform activities of daily living. Direct motor instruction in cerebella ataxia patients has limited effectiveness, presumably because an inappropriate closed-loop cerebellar response to the inevitable observed error confounds motor learning mechanisms. Could the use of EEG based BCI provide advanced biofeedback to improve motor imagery and provide a “backdoor” to improving motor performance in ataxia patients? In order to determine the feasibility of using EEG-based BCI control in this population, we compare the ability to modulate mu-band power (8-12 Hz) by performing a cued motor imagery task in an ataxia patient and healthy control.

Keywords: Cerebellar ataxia, Electroencephalogram, brain-computer interface, motor imagery.

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4472 Current Status of Nitrogen Saturation in the Upper Reaches of the Kanna River, Japan

Authors: Sakura Yoshii, Masakazu Abe, Akihiro Iijima

Abstract:

Nitrogen saturation has become one of the serious issues in the field of forest environment. The watershed protection forests located in the downwind hinterland of Tokyo Metropolitan Area are believed to be facing nitrogen saturation. In this study, we carefully focus on the balance of nitrogen between load and runoff. Annual nitrogen load via atmospheric deposition was estimated to 461.1 t-N/year in the upper reaches of the Kanna River. Annual nitrogen runoff to the forested headwater stream of the Kanna River was determined to 184.9 t-N/year, corresponding to 40.1% of the total nitrogen load. Clear seasonal change in NO3-N concentration was still observed. Therefore, watershed protection forest of the Kanna River is most likely to be in Stage-1 on the status of nitrogen saturation.

Keywords: Atmospheric deposition, Nitrogen accumulation, Denitrification, Forest ecosystems.

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4471 Effect of Selenite and Selenate Uptake by Maize Plants on Specific Leaf Area

Authors: F. Garousi, Sz. Veres, É. Bódi, Sz. Várallyay, B. Kovács

Abstract:

Specific leaf area (SLA; cm2leaf g-1leaf) the ratio of leaf area to leaf dry mass is a key ecophysiological parameter influencing leaf physiology, photosynthesis, and whole plant carbon gain and also can be used as a rapid and diagnostic tool. In this study, two species of soluble inorganic selenium forms, selenite (Se^IV) and selenate (Se^VI) at different concentrations were investigated on maize plants that were growing in nutrient solutions during 2 weeks and at the end of the experiment, amounts of SLA for first and second leaves of maize were measured. In accordance with the results we observed that our regarded Se concentrations in both forms of Se^IV and Se^VI were not effective on maize plants’ SLA significantly although high level of 3 mg.kg-1 Se^IV had negative affect on growth of the samples that had been treated by it but about Se^VI samples we did not observe this state and our different considered Se^VI concentrations were not toxic for maize plants.

Keywords: Maize, Sodium selenate, sodium selenite, specific leaf area.

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4470 Investigation of the Effect of Fine-Grained and Its Plastic Properties on Liquefaction Resistance of Sand

Authors: S. A. Naeini, M. Mortezaee

Abstract:

The purpose of this paper is to investigate the effect of fine grain content in soil and its plastic properties on soil liquefaction potential. For this purpose, the conditions for considering the fine grains effect and percentage of plastic fine on the liquefaction resistance of saturated sand presented by researchers has been investigated. Then, some comprehensive results of all the issues raised by some researchers are stated. From these investigations it was observed that by increasing the percentage of cohesive fine grains in the sandy soil (up to 20%), the maximum shear strength decreases and by adding more fine- grained percentage, the maximum shear strength of the resulting soil increases but never reaches the amount of clean sand.

Keywords: Fine-grained, liquefaction, plasticity, shear strength, sand.

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4469 Possibilities of Sewage Sludge Application in the Conditions of Slovak Republic

Authors: Peter Takáč, Dana Šimová, Terézia Szabová, Tomáš Bakalár

Abstract:

The direct sewage sludge application is a relative cheap method for their liquidation. In the past heavy metal contents increase in soils treated with sewage sludge was observed. In 2003 there was acceptance on act n.188/2003 about sewage sludge application on soils. The basic philosophy of act is a safety of the environmental proof of sludge application on soils. The samples of soils from wastewater treatment plant (WTP) Poprad (35) and WTP Michalovce (33 samples) were analyzed which were chosen for sludge application on soils. According to the results only 14 areas for Poprad and 25 areas for Michalovce are suitable for sludge application according to act No. 188/2003. The application dose of sludge was calculated 50 t.ha-1 or 75 t. ha-1 once in 5 years to ensure that heavy metal contents in treated soils will be kept.

Keywords: Environmental safety, heavy metals in soils, sewagesludge application.

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4468 The Key Role of the Steroidal Hormones in the Pattern Distribution of the Epiphyseal Structure in Rabbit

Authors: Fatahian Dehkordi R.F, Parchami A.

Abstract:

Steroidal hormones with the efficient changes on the epiphyseal growth plate may influence tissue structure properties. Presents paper to investigate the effects of gonadectomy in the pattern distribution of the epiphyseal structure. Fifteen adult female New Zealand white rabbits were separated into three groups. One group was intact and others groups were selected for surgical operation. From these two groups, one group carried out steroidal administration. The results obtained showed that there is no statistically difference in the mean diameter of the growth plate cells between all three groups. The maximum value of the cartilage cells were allocated to the gonadectomized group and the minimum number were observed in Hormonal induced group significantly. Growth plate height was significantly greater in gonadectomized group than in two other groups.

Keywords: Steroidal hormones, Ovariectomy, Rabbit, Epiphyseal structure

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4467 Effect of Crude Extract from Bacillus Subtilis LB5 Cultivated Broth on Conidial Germination of Colletotrichum Gloeosporioides

Authors: Onuma Ruangwong, Wen-Jinn Liang

Abstract:

Bacillus subtilis strain LB5 produced lipopeptide antibiotic iturin A-2 in liquid medium. Crude extract from cell-free supernatant of B. subtilis cultivated broth extracted with n-butanol showed antifungal activity to conidial germination of Colletotrichum gloeosporioides. The germination of conidia was completely inhibited by crude extract. The ultrastructure of conidia after treated with crude extract was found an accumulation of vesiclelike material between cell wall and plasma membrane while this accumulation was not observed in untreated and germinated conidia. Besides, the cell wall was not affected by crude extract.

Keywords: Bacillus subtilis strain LB5, iturin A-2, Colletotrichum gloeosporioides, TEM, vesicle-like material.

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4466 21st Century Islam: Global Challenges of Islamic Representation and Knowledge Acquisition

Authors: M. M. Muhammed, O. Khuzaima

Abstract:

This research examined and outlined some of the challenges facing Islam and Muslims in the 21st century, considering global Islamic representation and knowledge acquisition as key objectives. It was observed that the Western media misrepresentation of Islam and the Western ethos embodied by the acquisition of western civilisation are major challenges faced by Islam and Muslims today. The problem of sectarianism, decline in the socio-economic power of Muslim communities and the archaic nature of the Islamic creed were recorded as major actors to the evolving global Islamic issues. It was therefore concluded that Islam is not the reason for these challenges, rather the action of some Muslims and non-Muslims were the contributing factors to the pandemics faced by Islam and Muslims. Some relevant recommendations were made to the Islamic world that could serve as effectual solutions to these lingering problems.

Keywords: Islam, challenges, Misrepresentation, twenty-first century.

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4465 Temperature Evolution, Microstructure and Mechanical Properties of Heat-Treatable Aluminum Alloy Welded by Friction Stir Welding: Comparison with Tungsten Inert Gas

Authors: Saliha Gachi, Mouloud Aissani, Fouad Boubenider

Abstract:

Friction Stir Welding (FSW) is a solid-state welding technique that can join material without melting the plates to be welded. In this work, we are interested to demonstrate the potentiality of FSW for joining the heat-treatable aluminum alloy 2024-T3 which is reputed as difficult to be welded by fusion techniques. Thereafter, the FSW joint is compared with another one obtained from a conventional fusion process Tungsten Inert Gas (TIG). FSW welds are made up using an FSW tool mounted on a milling machine. Single pass welding was applied to fabricated TIG joint. The comparison between the two processes has been made on the temperature evolution, mechanical and microstructure behavior. The microstructural examination revealed that FSW weld is composed of four zones: Base metal (BM), Heat affected zone (HAZ), Thermo-mechanical affected zone (THAZ) and the nugget zone (NZ). The NZ exhibits a recrystallized equiaxed refined grains that induce better mechanical properties and good ductility compared to TIG joint where the grains have a larger size in the welded region compared with the BM due to the elevated heat input. The microhardness results show that, in FSW weld, the THAZ contains the lowest microhardness values and increase in the NZ; however, in TIG process, the lowest values are localized on the NZ.

Keywords: Friction stir welding, tungsten inert gaz, aluminum, microstructure.

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4464 Ultrasensitive Hepatitis B Virus Detection in Blood Using Nano-Porous Silicon Oxide: Towards POC Diagnostics

Authors: N. Das, N. Samanta, L. Pandey, C. Roy Chaudhuri

Abstract:

Early diagnosis of infection like Hep-B virus in blood is important for low cost medical treatment. For this purpose, it is desirable to develop a point of care device which should be able to detect trace quantities of the target molecule in blood. In this paper, we report a nanoporous silicon oxide sensor which is capable of detecting down to 1fM concentration of Hep-B surface antigen in blood without the requirement of any centrifuge or pre-concentration. This has been made possible by the presence of resonant peak in the sensitivity characteristics. This peak is observed to be dependent only on the concentration of the specific antigen and not on the interfering species in blood serum. The occurrence of opposite impedance change within the pores and at the bottom of the pore is responsible for this effect. An electronic interface has also been designed to provide a display of the virus concentration.

Keywords: Impedance spectroscopy, Ultrasensitive detection in blood, Peak frequency, Electronic interface.

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4463 Experimental Study and Analysis of Parabolic trough Collector with Various Reflectors

Authors: Avadhesh Yadav, Manoj Kumar, Balram

Abstract:

A solar powered air heating system using parabolic trough collector was experimentally investigated. In this experimental setup, the reflected solar radiations were focused on absorber tube which was placed at focal length of the parabolic trough. In this setup, air was used as working fluid which collects the heat from absorber tube. To enhance the performance of parabolic trough, collector with different type of reflectors were used. It was observed For Aluminum sheet maximum temperature is 52.3ºC, which 24.22% more than steel sheet as reflector and 8.5% more than Aluminum foil as reflector, also efficiency by using Aluminum sheet as reflector compared to steel sheet as reflector is 61.18% more. Efficiency by using Aluminum sheet as reflector compared to Aluminum foil as reflector is 18.98% more.

Keywords: Parabolic trough collector, Reflectors, Air flow rates.

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4462 A Meta-Analytic Path Analysis of e-Learning Acceptance Model

Authors: David W.S. Tai, Ren-Cheng Zhang, Sheng-Hung Chang, Chin-Pin Chen, Jia-Ling Chen

Abstract:

This study reports results of a meta-analytic path analysis e-learning Acceptance Model with k = 27 studies, Databases searched included Information Sciences Institute (ISI) website. Variables recorded included perceived usefulness, perceived ease of use, attitude toward behavior, and behavioral intention to use e-learning. A correlation matrix of these variables was derived from meta-analytic data and then analyzed by using structural path analysis to test the fitness of the e-learning acceptance model to the observed aggregated data. Results showed the revised hypothesized model to be a reasonable, good fit to aggregated data. Furthermore, discussions and implications are given in this article.

Keywords: E-learning, Meta Analytic Path Analysis, Technology Acceptance Model

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4461 All Optical Wavelength Conversion Based On Four Wave Mixing in Optical Fiber

Authors: Surinder Singh, Gursewak Singh Lovkesh

Abstract:

We have designed wavelength conversion based on four wave mixing in an optical fiber at 10 Gb/s. The power of converted signal increases with increase in signal power. The converted signal power is investigated as a function of input signal power and pump power. On comparison of converted signal power at different value of input signal power, we observe that best converted signal power is obtained at -2 dBm input signal power for both up conversion as well as for down conversion. Further, FWM efficiency, quality factor is observed for increase in input signal power and optical fiber length.

Keywords: FWM, Optical fiber, Quality, Wavelength Converter.

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4460 Observation of the Correlations between Pair Wise Interaction and Functional Organization of the Proteins, in the Protein Interaction Network of Saccaromyces Cerevisiae

Authors: N. Tuncbag, T. Haliloglu, O. Keskin

Abstract:

Understanding the cell's large-scale organization is an interesting task in computational biology. Thus, protein-protein interactions can reveal important organization and function of the cell. Here, we investigated the correspondence between protein interactions and function for the yeast. We obtained the correlations among the set of proteins. Then these correlations are clustered using both the hierarchical and biclustering methods. The detailed analyses of proteins in each cluster were carried out by making use of their functional annotations. As a result, we found that some functional classes appear together in almost all biclusters. On the other hand, in hierarchical clustering, the dominancy of one functional class is observed. In brief, from interaction data to function, some correlated results are noticed about the relationship between interaction and function which might give clues about the organization of the proteins.

Keywords: Pair-wise protein interactions, DIP database, functional correlations, biclustering.

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4459 Influence of Hydrolytic Degradation on Properties of Moisture Membranes Used in Fire-Protective Clothing

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

Abstract:

This study intends to show the influence of the hydrolytic degradation on the properties of the e-PTFE/NOMEX® membranes used in fire-protective clothing. The modification of water vapour permeability, morphology and chemical structure was examined by MOCON Permatran, electron microscopy scanning (SEM), and ATR-FTIR, respectively. A decrease in permeability to water vapour of the aged samples was observed following closure of transpiration pores. Analysis of fiber morphology indicates the appearance of defects at the fibers surface with the presence of micro cavities. ATR-FTIR analysis reveals the presence of a new absorption band attributed to carboxylic acid terminal groups generated during the amide bond hydrolysis.

Keywords: Hydrolytic ageing, moisture membrane; water vapor permeability, morphology.

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4458 Developing ESL Students' Writing

Authors: Esmaeil Hassannejad

Abstract:

Some of the students' problems in writing skill stem from inadequate preparation for the writing assignment. Students should be taught how to write well when they arrive in language classes. Having selected a topic, the students examine and explore the theme from as large a variety of viewpoints as their background and imagination make possible. Another strategy is that the students prepare an Outline before writing the paper. The comparison between the two mentioned thought provoking techniques was carried out between the two class groups –students of Islamic Azad University of Dezful who were studying “Writing 2" as their main course. Each class group was assigned to write five compositions separately in different periods of time. Then a t-test for each pair of exams between the two class groups showed that the t-observed in each pair was more than the t-critical. Consequently, the first hypothesis which states those who utilize Brainstorming as a thought provoking technique in prewriting phase are more successful than those who outline the papers before writing was verified.

Keywords: Brainstorming, Outlining, Prewriting, Thought provoking techniques

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4457 Fluidity of A713 Cast Alloy with and without Scrap Addition using Double Spiral Fluidity Test: A Comparison

Authors: A.K. Birru, D Benny Karunakar, M. M. Mahapatra

Abstract:

Recycling of aluminum alloys often decrease fluidity, consequently influence the castability of the alloy. In this study, the fluidity of Al-Zn alloys, such as the standard A713 alloy with and without scrap addition has been investigated. The scrap added was comprised of contaminated alloy turning chips. Fluidity measurements were performed with double spiral fluidity test consisting of gravity casting of double spirals in green sand moulds with good reproducibility. The influence of recycled alloy on fluidity has been compared with that of the virgin alloy and the results showed that the fluidity decreased with the increase in recycled alloy at minimum pouring temperatures. Interestingly, an appreciable improvement in the fluidity was observed at maximum pouring temperature, especially for coated spirals.

Keywords: A713 alloy, Fluidity, Hexachloroethane, Pouring temperature, Recycling.

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4456 About the Structural Stability of the Model of the Nonelectroneutral Current Sheath

Authors: V.V. Lyahov, V.M. Neshchadim

Abstract:

The structural stability of the model of a nonelectroneutral current sheath is investigated. The stationary model of a current sheath represents the system of four connected nonlinear differential first-order equations and thus they should manifest structural instability property, i.e. sensitivity to the infinitesimal changes of parameters and starting conditions. Domains of existence of the solutions of current sheath type are found. Those solutions of the current sheath type are realized only in some regions of sevendimensional space of parameters of the problem. The phase volume of those regions is small in comparison with the whole phase volume of the definition range of those parameters. It is shown that the offered model of a nonelectroneutral current sheath is applicable for theoretical interpretation of the bifurcational current sheaths observed in the magnetosphere.

Keywords: Distribution function, electromagnetic field, magnetoactive plasma, nonelectroneutral current sheath, structural instability, bifurcational current sheath.

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4455 Sixth-Order Two-Point Efficient Family of Super-Halley Type Methods

Authors: Ramandeep Behl, S. S. Motsa

Abstract:

The main focus of this manuscript is to provide a highly efficient two-point sixth-order family of super-Halley type methods that do not require any second-order derivative evaluation for obtaining simple roots of nonlinear equations, numerically. Each member of the proposed family requires two evaluations of the given function and two evaluations of the first-order derivative per iteration. By using Mathematica-9 with its high precision compatibility, a variety of concrete numerical experiments and relevant results are extensively treated to confirm t he t heoretical d evelopment. From their basins of attraction, it has been observed that the proposed methods have better stability and robustness as compared to the other sixth-order methods available in the literature.

Keywords: Basins of attraction, nonlinear equations, simple roots, Super-Halley.

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4454 Video Quality Assessment using Visual Attention Approach for Sign Language

Authors: Julia Kucerova, Jaroslav Polec, Darina Tarcsiova

Abstract:

Visual information is very important in human perception of surrounding world. Video is one of the most common ways to capture visual information. The video capability has many benefits and can be used in various applications. For the most part, the video information is used to bring entertainment and help to relax, moreover, it can improve the quality of life of deaf people. Visual information is crucial for hearing impaired people, it allows them to communicate personally, using the sign language; some parts of the person being spoken to, are more important than others (e.g. hands, face). Therefore, the information about visually relevant parts of the image, allows us to design objective metric for this specific case. In this paper, we present an example of an objective metric based on human visual attention and detection of salient object in the observed scene.

Keywords: sign language, objective video quality, visual attention, saliency

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4453 Electron-Impact Excitation of Kr 5s, 5p Levels

Authors: Alla A. Mityureva

Abstract:

The available data on the cross sections of electronimpact excitation of krypton 5s and 5p configuration levels out of the ground state are represented in convenient and compact form. The results are obtained by regression through all known published data related to this process.

Keywords: Cross section, electron excitation, krypton, regression

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4452 Investigation of Layer Thickness and Surface Roughness on Aerodynamic Coefficients of Wind Tunnel RP Models

Authors: S. Daneshmand, A. Ahmadi Nadooshan, C. Aghanajafi

Abstract:

Traditional wind tunnel models are meticulously machined from metal in a process that can take several months. While very precise, the manufacturing process is too slow to assess a new design's feasibility quickly. Rapid prototyping technology makes this concurrent study of air vehicle concepts via computer simulation and in the wind tunnel possible. This paper described the Affects layer thickness models product with rapid prototyping on Aerodynamic Coefficients for Constructed wind tunnel testing models. Three models were evaluated. The first model was a 0.05mm layer thickness and Horizontal plane 0.1μm (Ra) second model was a 0.125mm layer thickness and Horizontal plane 0.22μm (Ra) third model was a 0.15mm layer thickness and Horizontal plane 4.6μm (Ra). These models were fabricated from somos 18420 by a stereolithography (SLA). A wing-body-tail configuration was chosen for the actual study. Testing covered the Mach range of Mach 0.3 to Mach 0.9 at an angle-of-attack range of -2° to +12° at zero sideslip. Coefficients of normal force, axial force, pitching moment, and lift over drag are shown at each of these Mach numbers. Results from this study show that layer thickness does have an effect on the aerodynamic characteristics in general; the data differ between the three models by fewer than 5%. The layer thickness does have more effect on the aerodynamic characteristics when Mach number is decreased and had most effect on the aerodynamic characteristics of axial force and its derivative coefficients.

Keywords: Aerodynamic characteristics, stereolithography, layer thickness, Rapid prototyping, surface finish.

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4451 An Examination of Backing Effects on Ratings for Masonry Arch Bridges

Authors: Muhammad E. Rahman, Paul J. Fanning

Abstract:

Many single or multispan arch bridges are strengthened with the addition of some kind of structural support between adjacent arches of multispan or beside the arch barrel of a single span to increase the strength of the overall structure. It was traditionally formed by either placing loose rubble masonry blocks between the arches and beside the arches or using mortar or concrete to construct a more substantial structural bond between the spans. On the other hand backing materials are present in some existing bridges. Existing arch assessment procedures generally ignore the effects of backing materials. In this paper an investigation of the effects of backing on ratings for masonry arch bridges is carried out. It is observed that increasing the overall lateral stability of the arch system through the inclusion of structural backing results in an enhanced failure load by reducing the likelihood of any tension occurring at the top of the arch.

Keywords: Arch, Backing, Bridge, Masonry

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4450 2D Numerical Analysis of Sao Paulo Tunnel

Authors: A.H. Akhaveissy

Abstract:

Nonlinear finite element method and Serendipity eight nodes element are used for determining of ground surface settlement due to tunneling. Linear element with elastic behavior is used for modeling of lining. Modified Generalized plasticity model with nonassociated flow rule is applied for analysis of a tunnel in Sao Paulo – Brazil. The tunnel had analyzed by Lades- model with 16 parameters. In this work modified Generalized Plasticity is used with 10 parameters, also Mohr-Coulomb model is used to analysis the tunnel. The results show good agreement with observed results of field data by modified Generalized Plasticity model than other models. The obtained result by Mohr-Coulomb model shows less settlement than other model due to excavation.

Keywords: Non-associated flow rule, Generalized plasticity, tunnel excavation, Excavation method.

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4449 Optimization of Biodiesel Production from Sunflower Oil Using Central Composite Design

Authors: Pascal Mwenge, Jefrey Pilusa, Tumisang Seodigeng

Abstract:

The current study investigated the effect of catalyst ratio and methanol to oil ratio on biodiesel production by using central composite design. Biodiesel was produced by transesterification using sodium hydroxide as a homogeneous catalyst, a laboratory scale reactor consisting of flat bottom flask mounts with a reflux condenser and a heating plate was used to produce biodiesel. Key parameters, including, time, temperature and mixing rate were kept constant at 60 minutes, 60 oC and 600 RPM, respectively. From the results obtained, it was observed that the biodiesel yield depends on catalyst ratio and methanol to oil ratio. The highest yield of 50.65% was obtained at catalyst ratio of 0.5 wt.% and methanol to oil mole ratio 10.5. The analysis of variances of biodiesel yield showed the R Squared value of 0.8387. A quadratic mathematical model was developed to predict the biodiesel yield in the specified parameters ranges.

Keywords: ANOVA, biodiesel, catalyst, CCD, transesterification.

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4448 Modeling of Single-Particle Impact in Abrasive Water Jet Machining

Authors: S. Y. Ahmadi-Brooghani, H. Hassanzadeh, P. Kahhal

Abstract:

This work presents a study on the abrasive water jet (AWJ) machining. An explicit finite element analysis (FEA) of single abrasive particle impact on stainless steel 1.4304 (AISI 304) is conducted. The abrasive water jet machining is modeled by FEA software ABAQUS/CAE. Shapes of craters in FEM simulation results were used and compared with the previous experimental and FEM works by means of crater sphericity. The influence of impact angle and particle velocity was observed. Adaptive mesh domain is used to model the impact zone. Results are in good agreement with those obtained from the experimental and FEM simulation. The crater-s depth is also obtained for different impact angle and abrasive particle velocities.

Keywords: Abrasive water jet machining, Adaptive meshcontrol, Explicit finite elements analysis, Single-particle impact.

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4447 Role of Selenite and Selenate Uptake by Maize Plants in Chlorophyll A and B Content

Authors: F. Garousi, S. Veres, É. Bódi, S. Várallyay, B. Kovács

Abstract:

Extracting and determining chlorophyll pigments (chlorophyll a and b) in green leaves are the procedures based on the solvent extraction of pigments in samples using N,Ndimethylformamide as the extractant. In this study, two species of soluble inorganic selenium forms, selenite (SeIV) and selenate (SeVI) at different concentrations were investigated on maize plants that were growing in nutrient solutions during 2 weeks and at the end of the experiment, amounts of chlorophyll a and b for first and second leaves of maize were measured. In accordance with the results we observed that our regarded Se concentrations in both forms of SeIV and SeVI were not effective on maize plants’ chlorophyll a and b significantly although high level of 3 mg.kg-1 SeIV had negative affect on growth of the samples that had been treated by it but about SeVI samples we did not observe this state and our different considered SeVI concentrations were not toxic for maize plants.

Keywords: Maize, sodium selenate, sodium selenite, chlorophyll a and b.

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4446 Pervasiveness of Aflatoxin in Peanuts Growing in the Area of Pothohar, Pakistan

Authors: Mateen Abbas, Abdul Muqeet Khan, Muhammad Rafique Asi, Javed Akhtar

Abstract:

Mycotoxin (aflatoxins) contamination of peanuts is a great concern for human health. A total of 72 samples of unripe, roasted, and salty peanuts were collected randomly from Pothohar plateau of Pakistan for the assessment of aflatoxin. Samples were dried, ground and extracted by acetonitrile (84%). The filtered extracts were cleaned up by MycoSep-226 and analyzed by high performance liquid chromatography with flourescence detector. Quantification limit of Aflatoxin was 1 μg/kg and 70% Recovery was observed in spiked samples in the range 1–10 μg/kg. The screening of mycotoxins indicated that aflatoxins were present in most of the samples being detected in 82%, in concentrations from 14.25 μg/kg to 98.80 μg/kg. Optimal conditions for mycotoxin production and fungal growth are frequently found in the crop fields as well as in store houses. Human exposure of such toxin can be controlled by pointed out such awareness and implemented the regulations.

Keywords: Aflatoxin, HPLC, Pakistan, Peanuts, Punjab

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4445 The Collapse of a Crane on Site: A Case Study

Authors: T. Teruzzi, S. Antonietti, C. Mosca, C. Paglia

Abstract:

This paper discusses the causes of the structural failure in a tower crane. The structural collapse occurred at the upper joints of the extension element used to increase the height of the crane. The extension element consists of a steel lattice structure made with angular profiles and plates joined to the tower element by arc welding. Macroscopic inspection of the sections showed that the break was always observed on the angular profiles at the weld bead edge. The case study shows how, using mechanical characterization, chemical analysis of the steel and macroscopic and microscopic metallographic examinations, it was possible to obtain significant evidence that identified the mechanism causing the breakage. The analyses identified the causes of the structural failure as the use of materials that were not suitable for welding and poor performance in the welding joints.

Keywords: Failure, weld, microstructure, microcracks.

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4444 Performance of Nakagami Fading Channel over Energy Detection Based Spectrum Sensing

Authors: M. Ranjeeth, S. Anuradha

Abstract:

Spectrum sensing is the main feature of cognitive radio technology. Spectrum sensing gives an idea of detecting the presence of the primary users in a licensed spectrum. In this paper we compare the theoretical results of detection probability of different fading environments like Rayleigh, Rician, Nakagami-m fading channels with the simulation results using energy detection based spectrum sensing. The numerical results are plotted as Pf Vs Pd for different SNR values, fading parameters. It is observed that Nakagami fading channel performance is better than other fading channels by using energy detection in spectrum sensing. A MATLAB simulation test bench has been implemented to know the performance of energy detection in different fading channel environment.

Keywords: Spectrum sensing, Energy detection, fading channels, Probability of detection, probability of false alarm.

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