Search results for: Cross moments
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 939

Search results for: Cross moments

699 Reliability of Slender Reinforced Concrete Columns: Part 1

Authors: Metwally Abdel Aziz Ahmed, Ahmed Shaban Abdel Hay Gabr, Inas Mohamed Saleh

Abstract:

The main objective of structural design is to ensure safety and functional performance requirements of a structural system for its target reliability levels. In this study, the reliability index for the reinforcement concrete slender columns with rectangular cross section is studied. The variable parameters studied include the loads, the concrete compressive strength, the steel yield strength, the dimensions of concrete cross-section, the reinforcement ratio, and the location of steel placement. Risk analysis program was used to perform the analytical study. The effect of load eccentricity on the reliability index of reinforced concrete slender column was studied and presented. The results of this study indicate that the good quality control improve the performance of slender reinforced columns through increasing the reliability index β.

Keywords: Reliability, reinforced concrete, safety, slender column.

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698 Quantitative Analysis of Weld Defect Images in Industrial Radiography Based Invariant Attributes

Authors: N. Nacereddine, M. Tridi, S. S. Belaïfa, M. Zelmat

Abstract:

For the characterization of the weld defect region in the radiographic image, looking for features which are invariant regarding the geometrical transformations (rotation, translation and scaling) proves to be necessary because the same defect can be seen from several angles according to the orientation and the distance from the welded framework to the radiation source. Thus, panoply of geometrical attributes satisfying the above conditions is proposed and which result from the calculation of the geometrical parameters (surface, perimeter, etc.) on the one hand and the calculation of the different order moments, on the other hand. Because the large range in values of the raw features and taking into account other considerations imposed by some classifiers, the scaling of these values to lie between 0 and 1 is indispensable. The principal component analysis technique is used in order to reduce the number of the attribute variables in the aim to give better performance to the further defect classification.

Keywords: Geometric parameters, invariant attributes, principal component analysis, weld defect image.

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697 A Robust Image Watermarking Scheme using Image Moment Normalization

Authors: Latha Parameswaran, K. Anbumani

Abstract:

Multimedia security is an incredibly significant area of concern. A number of papers on robust digital watermarking have been presented, but there are no standards that have been defined so far. Thus multimedia security is still a posing problem. The aim of this paper is to design a robust image-watermarking scheme, which can withstand a different set of attacks. The proposed scheme provides a robust solution integrating image moment normalization, content dependent watermark and discrete wavelet transformation. Moment normalization is useful to recover the watermark even in case of geometrical attacks. Content dependent watermarks are a powerful means of authentication as the data is watermarked with its own features. Discrete wavelet transforms have been used as they describe image features in a better manner. The proposed scheme finds its place in validating identification cards and financial instruments.

Keywords: Watermarking, moments, wavelets, content-based, benchmarking.

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696 Role of Ionic Solutions Affect Water Treeing Propagation in XLPE Insulation for High Voltage Cable

Authors: T. Boonraksa, B. Marungsri

Abstract:

This paper presents the experimental results on role of ionic solutions affect water treeing propagation in cross-linked polyethylene insulation for high voltage cable. To study the water treeing expansion due to the ionic solutions, discs of 4mm thickness and 4cm diameter were taken from 115 kV XLPE insulation cable and were used as test specimen in this study. Ionic solutions composed of CuSO4, FeSO4, Na2SO4 and K2SO4 were used. Each specimen was immersed in 0.1 mole ionic solutions and was tested for 120 hrs. under a voltage stress at 7 kV AC rms, 1000 Hz. The results show that Na2SO4 and CuSO4solutions play an important role in the expansion of water treeing and cause degradation of the crosslinked polyethylene (XLPE) in the presence of the applied electric field.

Keywords: Ionic Solutions, Water Treeing, Water treeing Expansion, Cross-linked Polyethylene (XLPE).

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695 UD Covariance Factorization for Unscented Kalman Filter using Sequential Measurements Update

Authors: H. Ghanbarpour Asl, S. H. Pourtakdoust

Abstract:

Extended Kalman Filter (EKF) is probably the most widely used estimation algorithm for nonlinear systems. However, not only it has difficulties arising from linearization but also many times it becomes numerically unstable because of computer round off errors that occur in the process of its implementation. To overcome linearization limitations, the unscented transformation (UT) was developed as a method to propagate mean and covariance information through nonlinear transformations. Kalman filter that uses UT for calculation of the first two statistical moments is called Unscented Kalman Filter (UKF). Square-root form of UKF (SRUKF) developed by Rudolph van der Merwe and Eric Wan to achieve numerical stability and guarantee positive semi-definiteness of the Kalman filter covariances. This paper develops another implementation of SR-UKF for sequential update measurement equation, and also derives a new UD covariance factorization filter for the implementation of UKF. This filter is equivalent to UKF but is computationally more efficient.

Keywords: Unscented Kalman filter, Square-root unscentedKalman filter, UD covariance factorization, Target tracking.

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694 Extending the Aspect Oriented Programming Joinpoint Model for Memory and Type Safety

Authors: Amjad Nusayr

Abstract:

Software security is a general term used to any type of software architecture or model in which security aspects are incorporated in this architecture. These aspects are not part of the main logic of the underlying program. Software security can be achieved using a combination of approaches including but not limited to secure software designs, third part component validation, and secure coding practices. Memory safety is one feature in software security where we ensure that any object in memory is have a valid pointer or a reference with a valid type. Aspect Oriented Programming (AOP) is a paradigm that is concerned with capturing the cross-cutting concerns in code development. AOP is generally used for common cross-cutting concerns like logging and Database transaction managing. In this paper we introduce the concepts that enable AOP to be used for the purpose of memory and type safety. We also present ideas for extending AOP in software security practices.

Keywords: Aspect oriented programming, programming languages, software security, memory and type safety.

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693 Two-Photon Ionization of Silver Clusters

Authors: V. Paployan, K. Madoyan, A. Melikyan, H. Minassian

Abstract:

In this paper, we calculate the two-photon ionization (TPI) cross-section for pump-probe scheme in Ag neutral cluster. The pump photon energy is assumed to be close to the surface plasmon (SP) energy of cluster in dielectric media. Due to this choice, the pump wave excites collective oscillations of electrons-SP and the probe wave causes ionization of the cluster. Since the interband transition energy in Ag exceeds the SP resonance energy, the main contribution into the TPI comes from the latter. The advantage of Ag clusters as compared to the other noble metals is that the SP resonance in silver cluster is much sharper because of peculiarities of its dielectric function. The calculations are performed by separating the coordinates of electrons corresponding to the collective oscillations and the individual motion that allows taking into account the resonance contribution of excited SP oscillations. It is shown that the ionization cross section increases by two orders of magnitude if the energy of the pump photon matches the surface plasmon energy in the cluster.

Keywords: Resonance enhancement, silver clusters, surface plasmon, two-photon ionization.

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692 Theoretical and Analytical Approaches for Investigating the Relations between Sediment Transport and Channel Shape

Authors: Nidal Hadadin

Abstract:

This study investigated the effect of cross sectional geometry on sediment transport rate. The processes of sediment transport are generally associated to environmental management, such as pollution caused by the forming of suspended sediment in the channel network of a watershed and preserving physical habitats and native vegetations, and engineering applications, such as the influence of sediment transport on hydraulic structures and flood control design. Many equations have been proposed for computing the sediment transport, the influence of many variables on sediment transport has been understood; however, the effect of other variables still requires further research. For open channel flow, sediment transport capacity is recognized to be a function of friction slope, flow velocity, grain size, grain roughness and form roughness, the hydraulic radius of the bed section and the type and quantity of vegetation cover. The effect of cross sectional geometry of the channel on sediment transport is one of the variables that need additional investigation. The width-depth ratio (W/d) is a comparative indicator of the channel shape. The width is the total distance across the channel and the depth is the mean depth of the channel. The mean depth is best calculated as total cross-sectional area divided by the top width. Channels with high W/d ratios tend to be shallow and wide, while channels with low (W/d) ratios tend to be narrow and deep. In this study, the effects of the width-depth ratio on sediment transport was demonstrated theoretically by inserting the shape factor in sediment continuity equation and analytically by utilizing the field data sets for Yalobusha River. It was found by utilizing the two approaches as a width-depth ratio increases the sediment transport decreases.

Keywords: Sediment transport, shape factor, hydraulicgeometry, flow discharge, width depth ratio.

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691 Image Compression Using Multiwavelet and Multi-Stage Vector Quantization

Authors: S. Esakkirajan, T. Veerakumar, V. Senthil Murugan, P. Navaneethan

Abstract:

The existing image coding standards generally degrades at low bit-rates because of the underlying block based Discrete Cosine Transform scheme. Over the past decade, the success of wavelets in solving many different problems has contributed to its unprecedented popularity. Due to implementation constraints scalar wavelets do not posses all the properties such as orthogonality, short support, linear phase symmetry, and a high order of approximation through vanishing moments simultaneously, which are very much essential for signal processing. New class of wavelets called 'Multiwavelets' which posses more than one scaling function overcomes this problem. This paper presents a new image coding scheme based on non linear approximation of multiwavelet coefficients along with multistage vector quantization. The performance of the proposed scheme is compared with the results obtained from scalar wavelets.

Keywords: Image compression, Multiwavelets, Multi-stagevector quantization.

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690 Fusion of Shape and Texture for Unconstrained Periocular Authentication

Authors: D. R. Ambika, K. R. Radhika, D. Seshachalam

Abstract:

Unconstrained authentication is an important component for personal automated systems and human-computer interfaces. Existing solutions mostly use face as the primary object of analysis. The performance of face-based systems is largely determined by the extent of deformation caused in the facial region and amount of useful information available in occluded face images. Periocular region is a useful portion of face with discriminative ability coupled with resistance to deformation. A reliable portion of periocular area is available for occluded images. The present work demonstrates that joint representation of periocular texture and periocular structure provides an effective expression and poses invariant representation. The proposed methodology provides an effective and compact description of periocular texture and shape. The method is tested over four benchmark datasets exhibiting varied acquisition conditions.

Keywords: Periocular authentication, Zernike moments, LBPV, shape and texture fusion.

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689 BTG-BIBA: A Flexibility-Enhanced Biba Model Using BTG Strategies for Operating System

Authors: Gang Liu, Can Wang, Runnan Zhang, Quan Wang, Huimin Song, Shaomin Ji

Abstract:

Biba model can protect information integrity but might deny various non-malicious access requests of the subjects, thereby decreasing the availability in the system. Therefore, a mechanism that allows exceptional access control is needed. Break the Glass (BTG) strategies refer an efficient means for extending the access rights of users in exceptional cases. These strategies help to prevent a system from stagnation. An approach is presented in this work for integrating Break the Glass strategies into the Biba model. This research proposes a model, BTG-Biba, which provides both an original Biba model used in normal situations and a mechanism used in emergency situations. The proposed model is context aware, can implement a fine-grained type of access control and primarily solves cross-domain access problems. Finally, the flexibility and availability improvement with the use of the proposed model is illustrated.

Keywords: Biba model, break the glass, context, cross-domain, fine-grained.

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688 Space Charge Distribution in 22 kV XLPE Insulated Cable by Using Pulse Electroacoustic Measurement Technique

Authors: N. Ruangkajonmathee, R. Thiamsri, B. Marungsri

Abstract:

This paper presents the experimental results on space charge distribution in cross-linked polyethylene (XLPE) insulating material for 22 kV power distribution system cable by using pulse electroacoustic measurement technique (PEA). Numbers of XLPE insulating material ribbon having thickness 60 μm taken from unused 22 kV high voltage cable were used as specimen in this study. DC electric field stress was applied to test specimen at room temperature (25°C). Four levels of electric field stress, 25 kV/mm, 50 kV/mm, 75 kV/mm and 100 kV/mm, were used. In order to investigate space charge distribution characteristic, space charge distribution characteristics were measured after applying electric field stress 15 min, 30 min and 60 min, respectively. The results show that applied time and magnitude of dc electric field stress play an important role to the formation of space charge.

Keywords: Space charge distribution, pulsed electroacoustic(PEA) technique, cross-linked polyethylene (XLPE), DC electrical fields stress.

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687 Dialect and Gender Variations in the Place and Manner of Articulation of the Korean Fricatives

Authors: Kyung-Im Han

Abstract:

This study examines dialect and gender variations in the place and manner of articulation between the two Korean fricatives, /s/ and /s’/, as produced by speakers of the Daegu and Jeju dialects. The acoustic parameters of center of gravity and skewness for the place of articulation, and the rise time and the amplitude rise slope for the manner of articulation were measured. The study results revealed a gender effect, but no dialect effect, for the center of gravity and the skewness. No main effect for either the gender or dialect was found for the rise time and the amplitude rise slope. These findings indicated that, with regard to the place of articulation, Korean fricative sound differences are a gender distinction, not a dialectal one.

Keywords: Dialect, gender, Korean fricative, manner of articulation, place of articulation, spectral moments.

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686 Improving Human Hand Localization in Indoor Environment by Using Frequency Domain Analysis

Authors: Wipassorn Vinicchayakul, Pichaya Supanakoon, Sathaporn Promwong

Abstract:

A human’s hand localization is revised by using radar cross section (RCS) measurements with a minimum root mean square (RMS) error matching algorithm on a touchless keypad mock-up model. RCS and frequency transfer function measurements are carried out in an indoor environment on the frequency ranged from 3.0 to 11.0 GHz to cover federal communications commission (FCC) standards. The touchless keypad model is tested in two different distances between the hand and the keypad. The initial distance of 19.50 cm is identical to the heights of transmitting (Tx) and receiving (Rx) antennas, while the second distance is 29.50 cm from the keypad. Moreover, the effects of Rx angles relative to the hand of human factor are considered. The RCS input parameters are compared with power loss parameters at each frequency. From the results, the performance of the RCS input parameters with the second distance, 29.50 cm at 3 GHz is better than the others.

Keywords: Radar cross section (RCS), fingerprint-based localization, minimum root mean square (RMS) error matching algorithm, touchless keypad model.

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685 Can Physical Activity and Dietary Fat Intake Influence Body Mass Index in a Cross-sectional Correlational Design?

Authors: D.O. Omondi, L.O.A. Othuon, G.M. Mbagaya

Abstract:

The purpose of this study was to determine the influence of physical activity and dietary fat intake on Body Mass Index (BMI) of lecturers within a higher learning institutionalized setting. The study adopted a Cross-sectional Correlational Design and included 120 lecturers selected proportionately by simple random sampling techniques from a population of 600 lecturers. Data was collected using questionnaires, which had sections including physical activity checklist adopted from the international physical activity questionnaire (IPAQ), 24-hour food recall, anthropometric measurements mainly weight and height. Analysis involved the use of bivariate correlations and linear regression. A significant inverse association was registered between BMI and duration (in minutes) spent doing moderate intense physical activity per day (r=-0.322, p<0.01). Physical activity also predicted BMI (r2=0.096, F=13.616, β=-3.22, t=-3.69, n=120, P<0.01). However, the association between Body Mass Index and dietary fat was not significant (r=0.038, p>0.05). Physical activity emerged as a more powerful determinant of BMI compared to dietary fat intake.

Keywords: Physical activity, dietary fat intake, Body MassIndex, Kenya.

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684 Marital Duration and Sexual Frequency among the Muslim and Santal Couples in Rural Bangladesh: A Cross-Cultural Perspective

Authors: Md. Emaj Uddin

Abstract:

Age and sex are biological terms that are socioculturally constructed for marriage and marital sexual behavior in every society. Marriage is a universal norm that makes legitimate sexual behavior between a man and a woman in marital life cycle to gain bio-social purposes. Cross-cultural studies reveal that marital sexual frequency as a part of marital sexual behavior not only varies within the couple-s life cycle, but also varies between and among couples in diverse cultures. The purpose of the study was to compare marital sexual frequency in association with age status and length of marital relationship between Muslim and Santal couples in rural Bangladesh. For this we assumed that (1) Santal culture compared to Muslim culture preferred earlier age at marriage for meeting marital sexual purposes in rural Bangladesh; (2) Marital duration among the Muslim couples was higher than that among the Santal couples; (3) Sexual frequency among the younger couples in both the ethnic communities was higher than the older couples; (4) Sexual frequency across the Muslim couples- marital life cycle was higher than that the Santal couples- marital life cycle. In so doing, 288 active couples (145 for Muslim and 143 for Santal) selected by cluster random sampling were interviewed with questionnaire method. The findings of Independent Samples T Test on age at marriage, current age, marital duration and sexual frequency independently reveal that there were significant differences in sexual frequency not only across the couples- life cycle but also vary between the Muslim and Santal couples in relation to marital duration. The results of Pearson-s Inter- Correlation Coefficients reveal that although age at marriage, current age and marital duration for husband and wife were significantly positive correlated with each other between the communities, there were significantly negative correlation between the age at marriage, current age, marital duration and sexual frequency among the selected couples between the communities.

Keywords: Bangladesh, Cross-Cultural Perspective, MaritalDuration, Muslim, Santal, Marital Sexual Frequency.

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683 Self-Propelled Intelligent Robotic Vehicle Based on Octahedral Dodekapod to Move in Active Branched Pipelines with Variable Cross-Sections

Authors: Sergey N. Sayapin, Anatoly P. Karpenko, Suan H. Dang

Abstract:

Comparative analysis of robotic vehicles for pipe inspection is presented in this paper. The promising concept of self-propelled intelligent robotic vehicle (SPIRV) based on octahedral dodekapod for inspection and operation in active branched pipelines with variable cross-sections is reasoned. SPIRV is able to move in pipeline, regardless of its spatial orientation. SPIRV can also be used to move along the outside of the pipelines as well as in space between surfaces of annular tubes. Every one of faces of the octahedral dodekapod can clamp/unclamp a thing with a closed loop surface of various forms as well as put pressure on environmental surface of contact. These properties open new possibilities for its applications in SPIRV. We examine design principles of octahedral dodekapod as future intelligent building blocks for various robotic vehicles that can self-move and self-reconfigure.

Keywords: Modular robot, octahedral dodekapod, pipe inspection robot, spatial parallel structure.

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682 Effects of Duct Geometry, Thickness and Types of Liners on Transmission Loss for Absorptive Silencers

Authors: M. Kashfi, K. Jahani

Abstract:

Sound attenuation in absorptive silencers has been analyzed in this paper. The structure of such devices is as follows. When the rigid duct of an expansion chamber has been lined by a packed absorptive material under a perforated membrane, incident sound waves will be dissipated by the absorptive liners. This kind of silencer, usually are applicable for medium to high frequency ranges. Several conditions for different absorptive materials, variety in their thicknesses, and different shapes of the expansion chambers have been studied in this paper. Also, graphs of sound attenuation have been compared between empty expansion chamber and duct of silencer with applying liner. Plane waves have been assumed in inlet and outlet regions of the silencer. Presented results that have been achieved by applying finite element method (FEM), have shown the dependence of the sound attenuation spectrum to flow resistivity and the thicknesses of the absorptive materials, and geometries of the cross section (configuration of the silencer). As flow resistivity and thickness of absorptive materials increase, sound attenuation improves. In this paper, diagrams of the transmission loss (TL) for absorptive silencers in five different cross sections (rectangle, circle, ellipse, square, and rounded rectangle as the main geometry) have been presented. Also, TL graphs for silencers using different absorptive material (glass wool, wood fiber, and kind of spongy materials) as liner with three different thicknesses of 5 mm, 15 mm, and 30 mm for glass wool liner have been exhibited. At first, the effect of substances of the absorptive materials with the specific flow resistivity and densities on the TL spectrum, then the effect of the thicknesses of the glass wool, and at last the efficacy of the shape of the cross section of the silencer have been investigated.

Keywords: Transmission loss, absorptive material, flow resistivity, thickness, frequency.

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681 The Future of Hospitals: A Systematic Review in the Field of Architectural Design with a Disruptive Research and Development Approach

Authors: María Araya Léon, Ainoa Abella, Aura Murillo, Ricardo Guasch, Laura Clèries

Abstract:

This article aims to examine scientific theory framed within the term hospitals of the future from a multidisciplinary and cross-sectional perspective. To understand the connection that the various cross-sectional areas, we studied have with architectural spaces and to determine the future outlook of the works examined and how they can be classified into the categories of need/solution, evolution/revolution, collective/individual, and preventive/corrective. The changes currently taking place within the context of healthcare demonstrate how important these projects are and the need for companies to face future changes. A systematic review has been carried out focused on what will the hospitals of the future be like in relation to the elements that form part of their use, design, and architectural space experience, using the WOS database from 2016 to 2019. The large number of works about sensoring & big data and the scarce amount related to the area of materials is worth highlighting. Furthermore, no growth concerning future issues is envisaged over time. Regarding classifications, the articles we reviewed address evolutionary and collective solutions more, and in terms of preventive and corrective solutions, they were found at a similar level. Although our research focused on the future of hospitals, there is little evidence representing this approach. We also detected that, given the relevance of the research on how the built environment influences human health and well-being, these studies should be promoted within the context of healthcare. This article allows to find evidence on the future perspective from within the domain of hospital architecture, in order to create bridges between the productive sector of architecture and scientific theory. This will make it possible to detect R&D opportunities in each analyzed cross-section.

Keywords: Hospitals, trends, architectural space, disruptive approach.

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680 Relationship of Sleep Duration with Obesity and Dietary Intake

Authors: Seyed Ahmad Hosseini, Makan Cheraghpour, Saeed Shirali, Roya Rafie, Matin Ghanavati, Arezoo Amjadi, Meysam Alipour

Abstract:

Background: There is a mutual relationship between sleep duration and obesity. We studied the relationship between sleep duration with obesity and dietary Intake. Methods: This cross-sectional study was conducted on 444 male students in Ahvaz Jundishapur University of Medical Science. Dietary intake was analyzed by food frequency questionnaire (FFQ). Anthropometric indices were analyzed. Participants were being asked about their sleep duration and they were categorized into three groups according to their responses (less than six hours, between six and eight hours, and more than eight hours). Results: Macronutrient, micronutrient, and antioxidant intake did not show significant difference between three groups. Moreover, we did not observe any significant difference between anthropometric indices (weight, body mass index, waist circumference, and percentage body fat). Conclusions: Our study results show no significant relationship between sleep duration, nutrition pattern, and obesity. Further study is recommended.

Keywords: Sleep duration, obesity, dietary intake, cross-sectional.

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679 The Fatigue Damage Accumulation on Systems of Concentrators

Authors: Alexander Urbach, Mukharbij Banov, Vladislav Turko

Abstract:

Fatigue tests of specimen-s with numerous holes are presented. The tests were made up till fatigue cracks have been created on both sides of the hole. Their extension was stopping with pressed plastic deformation at the mouth of the detected crack. It is shown that the moments of occurrence of cracks on holes are stochastically dependent. This dependence has positive and negative correlation relations. Shown that the positive correlation is formed across of the applied force, while negative one – along it. The negative relationship extends over a greater distance. The mathematical model of dependence area formation is represented as well as the estimating of model parameters. The positive correlation of fatigue cracks origination can be considered as an extension of one main crack. With negative correlation the first crack locates the place of its origin, leading to the appearance of multiple cracks; do not merge with each other.

Keywords: Correlation analysis, fatigue damage accumulation, local area, mathematical model.

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678 Impact of Masonry Joints on Detection of Humidity Distribution in Aerated Concrete Masonry Constructions by Electric Impedance Spectrometry Measurements

Authors: Sanita Rubene, Martins Vilnitis, Juris Noviks

Abstract:

Aerated concrete is a load bearing construction material, which has high heat insulation parameters. Walls can be erected from aerated concrete masonry constructions and in perfect circumstances additional heat insulation is not required. The most common problem in aerated concrete heat insulation properties is the humidity distribution throughout the cross section of the masonry elements as well as proper and conducted drying process of the aerated concrete construction because only dry aerated concrete masonry constructions can reach high heat insulation parameters. In order to monitor drying process of the masonry and detect humidity distribution throughout the cross section of aerated concrete masonry construction application of electrical impedance spectrometry is applied. Further test results and methodology of this non-destructive testing method is described in this paper.

Keywords: Aerated concrete, electrical impedance spectrometry, humidity distribution, non-destructive testing.

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677 Flow Visualization of Angled Supersonic Jets into a Supersonic Cross Flow

Authors: Yan Shao, Jin Zhou, Lin Lai, Haiyan Wu, Jing Lei

Abstract:

This paper describes Nano-particle based Planar Laser Scattering (NPLS) flow visualization of angled supersonic jets into a supersonic cross flow based on the HYpersonic Low TEmperature (HYLTE) nozzle which was widely used in DF chemical laser. In order to investigate the non-reacting flowfield in the HYLTE nozzle, a testing section with windows was designed and manufactured. The impact of secondary fluids orifice separation on mixing was examined. For narrow separation of orifices, the secondary fuel penetration increased obviously compared to diluent injection, which means smaller separation of diluent and fuel orifices would enhance the mixing of fuel and oxidant. Secondary injections with angles of 30, 40 and 50 degrees were studied. It was found that the injectant penetration increased as the injection angle increased, while the interfacial surface area to entrain the freestream fluid is largest when the injection angle is 40 degree.

Keywords: HYLTE nozzle, NPLS, supersonic mixing, transverse injection

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676 Understanding ICT Behaviors among Health Workers in Sub-Saharan Africa: A Cross-Sectional Study for Laboratory Persons in Uganda

Authors: M. Kasusse, M. Rosette, E. Burke, C. Mwangi, R. Batamwita, N. Tumwesigye, S. Aisu

Abstract:

A cross-sectional survey to ascertain the capacity of laboratory persons in using ICTs was conducted in 15 Ugandan districts (July-August 2013). A self-administered questionnaire served as data collection tool, interview guide and observation checklist. 69 questionnaires were filled, 12 interviews conducted, 45 HC observed. SPSS statistics 17.0 and SAS 9.2 software were used for entry and analyses. 69.35% of participants find it difficult to access a computer at work. Of the 30.65% who find it easy to access a computer at work, a significant 21.05% spend 0 hours on a computer daily. 60% of the participants cannot access internet at work. Of the 40% who have internet at work, a significant 20% lack email address but 20% weekly read emails weekly and 48% daily. It is viable/feasible to pilot informatics projects as strategies to build bridges develop skills for e-health landscape in laboratory services with a bigger financial muscle.

Keywords: ICT Behavior, Clinical Laboratory persons, Sub-Saharan Africa, Uganda.

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675 Cross-Cultural Socio-Economic Status Attainment between Muslim and Santal Couple in Rural Bangladesh

Authors: Md. Emaj Uddin

Abstract:

This study compared socio-economic status attainment between the Muslim and Santal couples in rural Bangladesh. For this we hypothesized that socio-economic status attainment (occupation, education and income) of the Muslim couples was higher than the Santal ones in rural Bangladesh. In order to examine the hypothesis 288 couples (145 couples for Muslim and 143 couples for Santal) selected by cluster random sampling from Kalna village, Bangladesh were individually interviewed with semistructured questionnaire method. The results of Pearson Chi-Squire test suggest that there were significant differences in socio-economic status attainment between the two communities- couples. In addition, Pearson correlation coefficients also suggest that there were significant associations between the socio-economic statuses attained by the two communities- couples in rural Bangladesh. Further crosscultural study should conduct on how inter-community relations in rural social structure of Bangladesh influence the differences among the couples- socio-economic status attainment

Keywords: Bangladesh, Couple, Cross-Cultural Comparison, Muslim, Socio-Economic Status Attainment, Santal.

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674 The Effect of Body Condition Score on Hormonal and Vaginal Histological Changes During Estrus of Synchronized Etawah Cross Bred Does

Authors: Diah Tri Widayati, Sunendar, Kresno Suharto, Pudji Asuti, Aris Junaid

Abstract:

Eight Etawah cross bred does were divided into two groups based on body condition score (BCS). Group I (BSC 2, body weight 25-30 kg; n = 4), and Group II (BSC 3, body weight, 35-40 kg, n=4). All does received intravaginal controlled internal drug release devices (CIDR) for 10 days, and a prostaglandin F2α at 48 h before CIDR removal. Estrus detection was carried out using vasectomized buck. Vaginal epithelium was taken to determine estrus cycle. Blood samples were taken every 3-6 hours, started from moment of CIDR removal until the end of estrus. The results showed vaginal histological indicated estrus occurred at the hours of 25 to 60 and 30 to 70 post CIDR removal in BCS 2 and 3, respectively. Progesterone peak of BCS 2 and BCS 3 were 0.18±0.31 and 0.48±0.31 ng/mL on the hour 0 post CIDR removal. Estradiol -17ß peak of each group was 53.25±35.08 and 89.91±92.84 pg/mL at 48 post CIDR removal. LH surge only occurred on BCS 3 groups, the LH concentrations were 9.9± 9.1; 4.5± 4.0; and 18.2± 9.1 ng/mL at 45, 48 and 51 hours post CIDR removal, respectively. It was concluded that the BCS had effects on vaginal histological changes and LH surge.

Keywords: Estrus synchronization, Vaginal histological changes, Progesterone, Estradiol -17ß , LH

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673 CFD Analysis on Aerodynamic Design Optimization of Wind Turbine Rotor Blades

Authors: R.S. Amano, R.J. Malloy

Abstract:

Wind energy has been shown to be one of the most viable sources of renewable energy. With current technology, the low cost of wind energy is competitive with more conventional sources of energy such as coal. Most blades available for commercial grade wind turbines incorporate a straight span-wise profile and airfoil shaped cross sections. These blades are found to be very efficient at lower wind speeds in comparison to the potential energy that can be extracted. However as the oncoming wind speed increases the efficiency of the blades decreases as they approach a stall point. This paper explores the possibility of increasing the efficiency of the blades at higher wind speeds while maintaining efficiency at the lower wind speeds. The design intends to maintain efficiency at lower wind speeds by selecting the appropriate orientation and size of the airfoil cross sections based on a low oncoming wind speed and given constant rotation rate. The blades will be made more efficient at higher wind speeds by implementing a swept blade profile. Performance was investigated using the computational fluid dynamics (CFD).

Keywords: CFD, wind turbine blade, renewable energy.

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672 Specific Emitter Identification Based on Refined Composite Multiscale Dispersion Entropy

Authors: Shaoying Guo, Yanyun Xu, Meng Zhang, Weiqing Huang

Abstract:

The wireless communication network is developing rapidly, thus the wireless security becomes more and more important. Specific emitter identification (SEI) is an vital part of wireless communication security as a technique to identify the unique transmitters. In this paper, a SEI method based on multiscale dispersion entropy (MDE) and refined composite multiscale dispersion entropy (RCMDE) is proposed. The algorithms of MDE and RCMDE are used to extract features for identification of five wireless devices and cross-validation support vector machine (CV-SVM) is used as the classifier. The experimental results show that the total identification accuracy is 99.3%, even at low signal-to-noise ratio(SNR) of 5dB, which proves that MDE and RCMDE can describe the communication signal series well. In addition, compared with other methods, the proposed method is effective and provides better accuracy and stability for SEI.

Keywords: Cross-validation support vector machine, refined composite multiscale dispersion entropy, specific emitter identification, transient signal, wireless communication device.

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671 Analysis of Hollow Rollers Implementation in Flexible Manufacturing of Large Bearings

Authors: S. Barabas, A.Fota.

Abstract:

In this paper is study the possibility of successfully implementing of hollow roller concept in order to minimize inertial mass of the large bearings, with major results in diminution of the material consumption, increasing of power efficiency (in wind power station area), increasing of the durability and life duration of the large bearings systems, noise reduction in working, resistance to vibrations, an important diminution of losses by abrasion and reduction of the working temperature. In this purpose was developed an original solution through which are reduced mass, inertial forces and moments of large bearings by using of hollow rollers. The research was made by using the method of finite element analysis applied on software type Solidworks - Nastran. Also, is study the possibility of rapidly changing the manufacturing system of solid and hollow cylindrical rollers.

Keywords: Large bearings, Von Mises stress, hollow rollers, flexible manufacturing system

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670 A New Method for Image Classification Based on Multi-level Neural Networks

Authors: Samy Sadek, Ayoub Al-Hamadi, Bernd Michaelis, Usama Sayed

Abstract:

In this paper, we propose a supervised method for color image classification based on a multilevel sigmoidal neural network (MSNN) model. In this method, images are classified into five categories, i.e., “Car", “Building", “Mountain", “Farm" and “Coast". This classification is performed without any segmentation processes. To verify the learning capabilities of the proposed method, we compare our MSNN model with the traditional Sigmoidal Neural Network (SNN) model. Results of comparison have shown that the MSNN model performs better than the traditional SNN model in the context of training run time and classification rate. Both color moments and multi-level wavelets decomposition technique are used to extract features from images. The proposed method has been tested on a variety of real and synthetic images.

Keywords: Image classification, multi-level neural networks, feature extraction, wavelets decomposition.

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