Search results for: test method.
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10073

Search results for: test method.

3503 Application of Particle Image Velocimetry in the Analysis of Scale Effects in Granular Soil

Authors: Zuhair Kadhim Jahanger, S. Joseph Antony

Abstract:

The available studies in the literature which dealt with the scale effects of strip footings on different sand packing systematically still remain scarce. In this research, the variation of ultimate bearing capacity and deformation pattern of soil beneath strip footings of different widths under plane-strain condition on the surface of loose, medium-dense and dense sand have been systematically studied using experimental and noninvasive methods for measuring microscopic deformations. The presented analyses are based on model scale compression test analysed using Particle Image Velocimetry (PIV) technique. Upper bound analysis of the current study shows that the maximum vertical displacement of the sand under the ultimate load increases for an increase in the width of footing, but at a decreasing rate with relative density of sand, whereas the relative vertical displacement in the sand decreases for an increase in the width of the footing. A well agreement is observed between experimental results for different footing widths and relative densities. The experimental analyses have shown that there exists pronounced scale effect for strip surface footing. The bearing capacity factors rapidly decrease up to footing widths B=0.25 m, 0.35 m, and 0.65 m for loose, medium-dense and dense sand respectively, after that there is no significant decrease in . The deformation modes of the soil as well as the ultimate bearing capacity values have been affected by the footing widths. The obtained results could be used to improve settlement calculation of the foundation interacting with granular soil.

Keywords: PIV, granular mechanics, scale effect, upper bound analysis.

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3502 Research of Ring MEMS Rate Integrating Gyroscopes

Authors: Hui Liu, Haiyang Quan

Abstract:

This paper To get the angle value with a MEMS rate gyroscope in some specific field, the usual method is to make an integral operation to the rate output, which will lead the error cumulating effect. So the rate gyro is not suitable. MEMS rate integrating gyroscope (MRIG) will solve this problem. A DSP system has been developed to implement the control arithmetic. The system can measure the angle of rotation directly by the control loops that make the sensor work in whole-angle mode. Modeling the system with MATLAB, desirable results of angle outputs are got, which prove the feasibility of the control arithmetic.

Keywords: Rate gyroscope, Rate integrating gyroscope, Whole angle mode, MATLAB modeling, DSP control.

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3501 LQR Control for a Multi-MW Wind Turbine

Authors: Trung-Kien Pham, Yoonsu Nam, Hyungun Kim, Jaehoon Son

Abstract:

This paper addresses linear quadratic regulation (LQR) for variable speed variable pitch wind turbines. Because of the inherent nonlinearity of wind turbine, a set of operating conditions is identified and then a LQR controller is designed for each operating point. The feedback controller gains are then interpolated linearly to get control law for the entire operating region. Besides, the aerodynamic torque and effective wind speed are estimated online to get the gain-scheduling variable for implementing the controller. The potential of the method is verified through simulation with the help of MATLAB/Simulink and GH Bladed. The performance and mechanical load when using LQR are also compared with that when using PI controller.

Keywords: variable speed variable pitch wind turbine, multi-MW size wind turbine, wind energy conversion system, LQR control.

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3500 Understanding and Predicting Foam in Anaerobic Digester

Authors: I. R. Kanu, T. J. Aspray, A. J. Adeloye

Abstract:

As a result of the ambiguity and complexity surrounding anaerobic digester foaming, efforts have been made by various researchers to understand the process of anaerobic digester foaming so as to proffer a solution that can be universally applied rather than site specific. All attempts ranging from experimental analysis to comparative review of other process has not fully explained the conditions and process of foaming in anaerobic digester. Studying the current available knowledge on foam formation and relating it to anaerobic digester process and operating condition, this piece of work presents a succinct and enhanced understanding of foaming in anaerobic digesters as well as introducing a simple method to identify the onset of anaerobic digester foaming based on analysis of historical data from a field scale system.

Keywords: Anaerobic digester, foam, biogas, surfactants, wastewater sludge.

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3499 Optimizing Turning Parameters for Cylindrical Parts Using Simulated Annealing Method

Authors: Farhad Kolahan, Mahdi Abachizadeh

Abstract:

In this paper, a simulated annealing algorithm has been developed to optimize machining parameters in turning operation on cylindrical workpieces. The turning operation usually includes several passes of rough machining and a final pass of finishing. Seven different constraints are considered in a non-linear model where the goal is to achieve minimum total cost. The weighted total cost consists of machining cost, tool cost and tool replacement cost. The computational results clearly show that the proposed optimization procedure has considerably improved total operation cost by optimally determining machining parameters.

Keywords: Optimization, Simulated Annealing, Machining Parameters, Turning Operation.

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3498 An Investigation of Quality Practices in Libyan Industrial Companies

Authors: Mostafa A. Shokshok, Omran Ali Abu Krais

Abstract:

This paper describes the collection and analysis of data obtained from face-to-face interviews conducted in selected Libyan industrial companies. The objectives of the interviews are to enhance understanding, and generate explanations of current issues in culture and quality management systems in Libyan companies. The method used in analyzing the questions, as well as the main finding of each question are explained. The interviews probed areas identify national and organizational culture, quality management systems, current methods, effects, barriers and other factors affecting the success of quality management implementation. Eleven questions are prepared and been discussed with the interviewees.

Keywords: Interviews, quality, culture, Libyan industrial companies.

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3497 Analytical Solutions of Three Dimensional Steady-State Heat Transfer in Rectangular Ribs

Authors: Tao Nie, Weiqiang Liu

Abstract:

In order to obtain an accurate result of the heat transfer of the rib in the internal cooling Rectangular channel, using separation of variables, analytical solutions of three dimensional steady-state heat conduction in rectangular ribs are given by solving three dimensional steady-state function of the rectangular ribs. Therefore, we can get solution of three dimensional temperature field in the rib. Based on the solution, we can get how the Bi number affected on heat transfer. Furthermore, comparisons of the analytical and numerical results indicate agreement on temperature field in the rib.

Keywords: variable separation method, analytical solution, rib, heat transfer

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3496 Progressive Collapse of Hyperbolic Cooling Tower Considering the Support Inclinations

Authors: Esmaeil Asadzadeh, Mehtab Alam

Abstract:

Progressive collapse of the layered hyperbolic tower shells are studied considering the influences of changes in the supporting columns’ types and angles. 3-D time history analyses employing the finite element method are performed for the towers supported with I-type and ᴧ-type column. It is found that the inclination angle of the supporting columns is a very important parameter in optimization and safe design of the cooling towers against the progressive collapse. It is also concluded that use of Demand Capacity Ratio (DCR) criteria of the linear elastic approach recommended by GSA is un-conservative for the hyperbolic tower shells.

Keywords: Progressive collapse, cooling towers, finite element analysis, crack generation, reinforced concrete.

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3495 Bowen Ratio in Western São Paulo State, Brazil

Authors: Elaine C. Barboza, Antonio J. Machado

Abstract:

This paper discusses micrometeorological aspects of the urban climate in three cities in Western São Paulo State: Presidente Prudente, Assis and Iepê. Particular attention is paid to the method used to estimate the components of the energy balance at the surface. Estimates of convective fluxes showed that the Bowen ratio was an indicator of the local climate and that its magnitude varied between 0.3 and 0.7. Maximum values for the Bowen ratio occurred earlier in Iepê (11:00 am) than in Presidente Prudente (4:00 pm). The results indicate that the Bowen ratio is modulated by the radiation balance at the surface and by different clusters of vegetation.

Keywords: Bowen ratio, medium-sized cities, surface energy balance, urban climate.

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3494 Non-Destructive Testing of Carbon Fiber Reinforced Plastic by Infrared Thermography Methods

Authors: W. Swiderski

Abstract:

Composite materials are one answer to the growing demand for materials with better parameters of construction and exploitation. Composite materials also permit conscious shaping of desirable properties to increase the extent of reach in the case of metals, ceramics or polymers. In recent years, composite materials have been used widely in aerospace, energy, transportation, medicine, etc. Fiber-reinforced composites including carbon fiber, glass fiber and aramid fiber have become a major structural material. The typical defect during manufacture and operation is delamination damage of layered composites. When delamination damage of the composites spreads, it may lead to a composite fracture. One of the many methods used in non-destructive testing of composites is active infrared thermography. In active thermography, it is necessary to deliver energy to the examined sample in order to obtain significant temperature differences indicating the presence of subsurface anomalies. To detect possible defects in composite materials, different methods of thermal stimulation can be applied to the tested material, these include heating lamps, lasers, eddy currents, microwaves or ultrasounds. The use of a suitable source of thermal stimulation on the test material can have a decisive influence on the detection or failure to detect defects. Samples of multilayer structure carbon composites were prepared with deliberately introduced defects for comparative purposes. Very thin defects of different sizes and shapes made of Teflon or copper having a thickness of 0.1 mm were screened. Non-destructive testing was carried out using the following sources of thermal stimulation, heating lamp, flash lamp, ultrasound and eddy currents. The results are reported in the paper.

Keywords: Non-destructive testing, IR thermography, composite material, thermal stimulation.

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3493 Single Valued Neutrosophic Hesitant Fuzzy Rough Set and Its Application

Authors: K. M. Alsager, N. O. Alshehri

Abstract:

In this paper, we proposed the notion of single valued neutrosophic hesitant fuzzy rough set, by combining single valued neutrosophic hesitant fuzzy set and rough set. The combination of single valued neutrosophic hesitant fuzzy set and rough set is a powerful tool for dealing with uncertainty, granularity and incompleteness of knowledge in information systems. We presented both definition and some basic properties of the proposed model. Finally, we gave a general approach which is applied to a decision making problem in disease diagnoses, and demonstrated the effectiveness of the approach by a numerical example.

Keywords: Single valued neutrosophic hesitant set, single valued neutrosophic hesitant relation, single valued neutrosophic hesitant fuzzy rough set, decision making method.

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3492 The Impact of Temporal Impairment on Quality of Experience (QoE) in Video Streaming: A No Reference (NR) Subjective and Objective Study

Authors: Muhammad Arslan Usman, Muhammad Rehan Usman, Soo Young Shin

Abstract:

Live video streaming is one of the most widely used service among end users, yet it is a big challenge for the network operators in terms of quality. The only way to provide excellent Quality of Experience (QoE) to the end users is continuous monitoring of live video streaming. For this purpose, there are several objective algorithms available that monitor the quality of the video in a live stream. Subjective tests play a very important role in fine tuning the results of objective algorithms. As human perception is considered to be the most reliable source for assessing the quality of a video stream subjective tests are conducted in order to develop more reliable objective algorithms. Temporal impairments in a live video stream can have a negative impact on the end users. In this paper we have conducted subjective evaluation tests on a set of video sequences containing temporal impairment known as frame freezing. Frame Freezing is considered as a transmission error as well as a hardware error which can result in loss of video frames on the reception side of a transmission system. In our subjective tests, we have performed tests on videos that contain a single freezing event and also for videos that contain multiple freezing events. We have recorded our subjective test results for all the videos in order to give a comparison on the available No Reference (NR) objective algorithms. Finally, we have shown the performance of no reference algorithms used for objective evaluation of videos and suggested the algorithm that works better. The outcome of this study shows the importance of QoE and its effect on human perception. The results for the subjective evaluation can serve the purpose for validating objective algorithms.

Keywords: Objective evaluation, subjective evaluation, quality of experience (QoE), video quality assessment (VQA).

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3491 Finding More Non-Supersingular Elliptic Curves for Pairing-Based Cryptosystems

Authors: Pu Duan, Shi Cui, Choong Wah Chan

Abstract:

Finding suitable non-supersingular elliptic curves for pairing-based cryptosystems becomes an important issue for the modern public-key cryptography after the proposition of id-based encryption scheme and short signature scheme. In previous work different algorithms have been proposed for finding such elliptic curves when embedding degree k ∈ {3, 4, 6} and cofactor h ∈ {1, 2, 3, 4, 5}. In this paper a new method is presented to find more non-supersingular elliptic curves for pairing-based cryptosystems with general embedding degree k and large values of cofactor h. In addition, some effective parameters of these non-supersingular elliptic curves are provided in this paper.

Keywords: Family of group order, kth root of unity, non-supersingular elliptic curves polynomial field.

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3490 Cognitive SATP for Airborne Radar Based on Slow-Time Coding

Authors: Fanqiang Kong, Jindong Zhang, Daiyin Zhu

Abstract:

Space-time adaptive processing (STAP) techniques have been motivated as a key enabling technology for advanced airborne radar applications. In this paper, the notion of cognitive radar is extended to STAP technique, and cognitive STAP is discussed. The principle for improving signal-to-clutter ratio (SCNR) based on slow-time coding is given, and the corresponding optimization algorithm based on cyclic and power-like algorithms is presented. Numerical examples show the effectiveness of the proposed method.

Keywords: Space-time adaptive processing (STAP), signal-to-clutter ratio, slow-time coding.

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3489 Magnetic Properties of NiO and MnO by LSDA+U

Authors: Chewa Thassana, Wicharn Techitdheera

Abstract:

The spin (ms) and orbital (mo) magnetic moment of the antiferromagnetic NiO and MnO have been studied in the local spin density approximation (LSDA+U) within full potential linear muffin-tin orbital (FP-LMTO method with in the coulomb interaction U varying from 0 to 10eV, exchange interaction J, from 0 to 1.0eV, and volume compression VC in range of 0 to 80%. Our calculated results shown that the spin magnetic moments and the orbital magnetic moments increase linearly with increasing U and J. While the interesting behaviour appears when volume compression is greater than 70% for NiO and 50% for MnO at which ms collapses. Further increase of volume compression to be at 80% leads to the disappearance of both magnetic moments.

Keywords: spin-orbital magnetic moment, Coulomb interaction U and exchange interaction J, volume compression VC, LSDA+U.

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3488 Assessing the Suitability of South African Waste Foundry Sand as an Additive in Clay Masonry Products

Authors: Nthabiseng Portia Mahumapelo, Andre van Niekerk, Ndabenhle Sosibo, Nirdesh Singh

Abstract:

The foundry industry generates large quantities of solid waste in the form of waste foundry sand. The ever-increasing quantities of this type of industrial waste put pressure on land-filling space and its proper management has become a global concern. The South African foundry industry is not different when it comes to this solid waste generation. Utilizing the foundry waste sand in other applications has become an attractive avenue to deal with this waste stream. In the present paper, an evaluation was done on the suitability of foundry waste sand as an additive in clay masonry products. Purchased clay was added to the foundry waste sand sample in a 50/50 ratio. The mixture was named FC sample. The FC sample was mixed with water in a pan mixer until the mixture was consistent and suitable for extrusion. The FC sample was extruded and cut into briquettes. Water absorption, shrinkage and modulus of rupture tests were conducted on the resultant briquettes. Foundry waste sand and FC samples were respectively characterized mineralogically using X-Ray Diffraction, and the major and trace elements were determined using Inductively Coupled Plasma Optical Emission Spectroscopy. Adding purchased clay to the foundry waste sand positively influenced the workability of the test sample. Another positive characteristic was the low linear shrinkage, which indicated that products manufactured from the FC sample would not be susceptible to cracking. The water absorption values were acceptable and the unfired and fired strength values of the briquette’s samples were acceptable. In conclusion, tests showed that foundry waste sand can be used as an additive in masonry clay bricks, provided it is blended with good quality clay.

Keywords: Foundry waste sand, masonry clay bricks, modulus of rupture, shrinkage.

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3487 Electrical Energy Harvesting Using Thermo Electric Generator for Rural Communities in India

Authors: N. Nandan A. M. Nagaraj, L. Sanjeev Kumar

Abstract:

In the rapidly growing population, the requirement of electrical power is increasing day by day. In order to meet the needs, we need to generate the power using alternate method. In this paper, a presentable approach is developed by analysis and can be implemented by utilizing heat energy, which is generated in numerous ways in some of the rural areas in India. The thermoelectric generator unit will be developed by combing with control circuits and converts, which is used to light the LED lamps. The temperature difference which is available in the kitchens, especially the exhaust pipes/chimneys of wooden fire stoves, where more heat is dissipated into the atmosphere, can be utilized for electrical power generation. Hence, the temperature rise of surroundings atmosphere can be reduced.

Keywords: Thermoelectric generator, LED, converts, temperature.

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3486 1/Sigma Term Weighting Scheme for Sentiment Analysis

Authors: Hanan Alshaher, Jinsheng Xu

Abstract:

Large amounts of data on the web can provide valuable information. For example, product reviews help business owners measure customer satisfaction. Sentiment analysis classifies texts into two polarities: positive and negative. This paper examines movie reviews and tweets using a new term weighting scheme, called one-over-sigma (1/sigma), on benchmark datasets for sentiment classification. The proposed method aims to improve the performance of sentiment classification. The results show that 1/sigma is more accurate than the popular term weighting schemes. In order to verify if the entropy reflects the discriminating power of terms, we report a comparison of entropy values for different term weighting schemes.

Keywords: Sentiment analysis, term weighting scheme, 1/sigma.

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3485 Influences of Juice Extraction and Drying Methods on the Chemical Analysis of Lemon Peels

Authors: Azza A. Abou-Arab, Marwa H. Mahmoud, Ferial M. Abu-Salem

Abstract:

This study aimed to determine the influence of some different juice extraction methods (screw type hand operated juice extractor and pressed squeeze juice extractor) as well as drying methods (microwave, solar and oven drying) on the chemical properties of lemon peels. It could be concluded that extraction of juice by screw type and drying of peel using the microwave drying method were the best preparative processing steps methods for lemon peel utilization as food additives.

Keywords: Lemon peel, extraction of juice methods, chemical analysis.

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3484 Fabricating Protruded Micro-features on AA6061 Substrates by Hot Embossing Method

Authors: Nhat Khoa Tran, Yee Cheong Lam, Chee Yoon Yue, Ming Jen Tan

Abstract:

Metallic micro parts are playing an important role in micro-fabrication industry. Recently, we have demonstrated a new deformation mechanism for micro-formability of polycrystalline materials. Different depressed micro-features smaller than the grain size have been successfully fabricated on 6061 aluminum alloy (AA6061) substrates with good fidelity. To further verify this proposed deformation mechanism that grain size is not a limiting factor, we demonstrate here that in addition of depressed features, protruded micro-features on a polycrystalline substrate can similarly be fabricated.

Keywords: Deformation mechanism, grain size, microfabrication, polycrystalline materials.

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3483 Numerical Modelling of Surface Waves Generated by Low Frequency Electromagnetic Field for Silicon Refinement Process

Authors: V. Geza, J. Vencels, G. Zageris, S. Pavlovs

Abstract:

One of the most perspective methods to produce SoG-Si is refinement via metallurgical route. The most critical part of this route is refinement from boron and phosphorus. Therefore, a new approach could address this problem. We propose an approach of creating surface waves on silicon melt’s surface in order to enlarge its area and accelerate removal of boron via chemical reactions and evaporation of phosphorus. A two dimensional numerical model is created which includes coupling of electromagnetic and fluid dynamic simulations with free surface dynamics. First results show behaviour similar to experimental results from literature.

Keywords: Numerical modelling, silicon refinement, surface waves, VOF method.

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3482 Aroma Composition and Polyphenol Content of Ciders Available in Latvian Market

Authors: Rita Riekstina-Dolge, Zanda Kruma, Daina Karklina

Abstract:

Aroma forming volatiles are important components of fermented beverages. The aim of current research is to evaluate the volatile compounds and phenolic compounds of commercial ciders. Volatile aroma compounds and TPC of seven commercial ciders were determined. Extraction of aroma compounds was performed using solid phase microextraction (DVB/Car/PDMS fibre). Analysis of volatile aroma compounds was made using a Perkin Elmer Clarus 500 GC/MS. Total phenol content (TPC) was determined according to the Folin-Ciocalteu spectrophotometric method and results were expressed as gallic acid equivalents. The highest volatile compounds were in apple ciders with pear flavor. The highest TPC and lower content of volatile compounds were detected in French ciders.

Keywords: cider, TPC, volatile compounds

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3481 Wind-Induced Phenomenon in a Closed Water Area with Floating-Leaved Plant

Authors: Akinori Ozaki

Abstract:

In this study, in order to clarify wind-induced phenomena, especially vertical mixing of density stratification in a closed water area with floating-leaved plants, we conducted hydraulic experiments on wind flow characteristics, wind wave characteristics, entrainment phenomena and turbulent structure by using a wind tunnel test tank and simulated floating-leaved plants. From the experimental results of wind flow and wind wave characteristics, we quantified the impact of the occupancy rate of the plants on their resistance characteristics. From the experimental results of entrainment phenomena, we defined the parameter that could explain the magnitude of mixing between the density stratifications, and quantified the impact of the occupancy rate on vertical mixing between stratifications. From the experimental results of the turbulent structure of the upper layer, we clarified the differences in small-scale turbulence components at each occupancy rate and quantified the impact of the occupancy rate on the turbulence characteristics. For a summary of this study, we theoretically quantified wind-induced entrainment phenomena in a closed water area with luxuriant growth of floating-leaved plants. The results indicated that the impact of luxuriant growth of floating-leaved plants in a closed water body could be seen in the difference in small-scale fluid characteristics, and these characteristics could be expressed using the small-scale turbulent components.

Keywords: Density Stratification, Floating-leaved Plant, Wind-induced Entrainment Phenomenon, Turbulent Structure

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3480 Fast Algorithm of Infrared Point Target Detection in Fluctuant Background

Authors: Yang Weiping, Zhang Zhilong, Li Jicheng, Chen Zengping, He Jun

Abstract:

The background estimation approach using a small window median filter is presented on the bases of analyzing IR point target, noise and clutter model. After simplifying the two-dimensional filter, a simple method of adopting one-dimensional median filter is illustrated to make estimations of background according to the characteristics of IR scanning system. The adaptive threshold is used to segment canceled image in the background. Experimental results show that the algorithm achieved good performance and satisfy the requirement of big size image-s real-time processing.

Keywords: Point target, background estimation, median filter, adaptive threshold, target detection.

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3479 Polyphenolic Profile and Antioxidant Activities of Nigella Sativa Seed Extracts In Vitro and In Vivo

Authors: Asma Meziti, Hicham Meziti, Kaouthar Boudiaf, Benboubetra Mustapha, Hemama Bouriche.

Abstract:

Nigella sativa L. is an aromatic plant belonging to the family Ranunculaceae. It has been used traditionally, especially in the middle East and India, for the treatment of asthma, cough, bronchitis, headache, rheumatism, fever, influenza and eczema. Several biological activities have been reported in Nigella sativa seeds, including antioxidant. In this context we tried to estimate the antioxidant activity of various extracts prepared from Nigella sativa seeds, methanolic extract (ME), chloroformic extract (CE), hexanic extract (HE : fixed oil), ethyl acetate extract (EAE) water extract (WE). The Folin-Ciocalteu assay showed that CE and EAE contained high level of phenolic compounds 81.31 and 72.43μg GAE/mg of extract respectively. Similarly, the CE and EAE exhibited the highest DPPH radical scavenging activity, with IC50 values of 106.56μg/ml and 121.62μg/ml respectively. In addition, CE and HE showed the most scavenging activity against superoxide radical generated in the PMS-NADH-NBT system with respective IC50 values of 361.86 μg/ml and 371.80 μg/ml, which is comparable to the activity of the standard antioxidant BHT (344.59 μg/ml). Ferrous ion chelating capacity assay showed that WE, EAE and ME are the most active with 40.57, 39.70 and 22.02 mg EDTA-E/g of extract. The inhibition of linoleic acid/ß-carotene coupled oxidation was estimated by ßcarotene bleaching assay, this showed a highest relative antioxidant activity with CE and EAE (69.82% of inhibition). The antioxidant activities of the methanolic extract and the fixed oil are confirmed by an in vivo assay in mice, the daily oral administration of methanolic extract (500 and 800 mg/kg/day) and fixed oil (2 and 4 ml/kg/day) during 21 days, resulted in a significant enhancement of the blood total antioxidant capacity (measured by KRL test) and the plasmatic antioxidant capacity towards DPPH radical.

Keywords: Antioxidant Capacity, Chelating, Phenolic Compounds, Nigella Sativa, Scavenger

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3478 Application of Generalized Taguchi and Design of Experiment Methodology for Rebar Production at an Integrated Steel Plant

Authors: S. B. V. S. P. Sastry, V. V. S. Kesava Rao

Abstract:

In this paper, x-ray impact of Taguchi method and design of experiment philosophy to project relationship between various factors leading to output yield strength of rebar is studied. In bar mill of an integrated steel plant, there are two production lines called as line 1 and line 2. The metallic properties e.g. yield strength of finished product of the same material is varying for a particular grade material when rolled simultaneously in both the lines. A study has been carried out to set the process parameters at optimal level for obtaining equal value of yield strength simultaneously for both lines.

Keywords: Bar mill, design of experiment, Taguchi, yield strength.

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3477 Atoms in Molecules, An Other Method For Analyzing Dibenzoylmethane

Authors: S. Heydarian

Abstract:

Proton transfer and hydrogen bonding are two aspects of the chemistry of hydrogen that respectively govern the behaviour and structure of many molecules, both simple and complex. All the theoretical enol and keto conformations of 1,3-diphenyl-1,3- propandion known as dibenzoylmethane (DBM), have been investigated by means of atoms in molecules (AIM) theory. It was found that the most stable conformers are those stabilized by hydrogen bridges.The aim of the present paper is a thorough conformational analysis of DBM (with special attention on chelated cis-enol conformers) in order to obtain detailed information on the geometrical parameters, relative stabilities and rotational motion of the phenyl groups. It is also important to estimate the barrier height for ptoton transfer and hydrogen bond strength, which are the main factors governing conformational stability.

Keywords: Acetylacetone, Atoms in molecules, Dibenzoylmethane, Intramolecular hydrogen bond, Resonanceconjugation

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3476 Shoplifting in Riyadh, Saudi Arabia

Authors: Saleh Dabil

Abstract:

the research was conducted using the self report of shoplifters who apprehended in the supermarket while stealing. 943 shoplifters in three years were interviewed right after the stealing act and before calling the police. The aim of the study is to know the shoplifting characteristics in Saudi Arabia, including the trait of shoplifters and the situation of the supermarkets where the stealing takes place. The analysis based on the written information about each thief as the documentary research method. Descriptive statistics as well as some inferential statistics were employed. The result shows that there are differences between genders, age groups, occupations, time of the day, days of the week, months, way of stealing, individual or group of thieves and other supermarket situations in the type of items stolen, total price and the count of items. The result and the recommendation will serve as a guide for retailers where, when and who to look at to prevent shoplifting.

Keywords: Shoplifting, stealing, theft, supermarket.

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3475 Effect of Exchange Interaction J on Magnetic Moment of MnO

Authors: C. Thassana, W. Techitdheera

Abstract:

This calculation focus on the effect of exchange interaction J and Coulomb interaction U on spin magnetic moments (ms) of MnO by using the local spin density approximation plus the Coulomb interaction (LSDA+U) method within full potential linear muffin-tin orbital (FP-LMTO). Our calculated results indicated that the spin magnetic moments correlated to J and U. The relevant results exhibited the increasing spin magnetic moments with increasing exchange interaction and Coulomb interaction. Furthermore, equations of spin magnetic moment, which h good correspondence to the experimental data 4.58μB, are defined ms = 0.11J +4.52μB and ms = 0.03U+4.52μB. So, the relation of J and U parameter is obtained, it is obviously, J = -0.249U+1.346 eV.

Keywords: exchange interaction J, the Coulomb interaction U, spin magnetic moment, LSDA+U, MnO.

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3474 Some Aspects of Social Media Marketing (Georgian Case)

Authors: Nugzar Todua, Charita Jashi

Abstract:

This paper is focusing on the attitude of Georgian consumers toward social media, influence of social media on consumer buying behavior. The purpose of this paper is to explore the usage of social media marketing for small business companies of Georgia. The result of marketing research has revealed that social webs are mostly used by Georgian consumers, but they have little impact on the buying decision. The research method was exploratory and descriptive. Conclusions summarize the research results and offers insight to provide better understandings of consumers demand and implementation of marketing strategy through social media in Georgia.

Keywords: Marketing Research, Purchasing behavior, Social Media Marketing, Small Business, Tourism Industry.

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