Search results for: effective length
2856 Comparison of Multi-User Detectors of DS-CDMA System
Authors: Kavita Khairnar, Shikha Nema
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DS-CDMA system is well known wireless technology. This system suffers from MAI (Multiple Access Interference) caused by Direct Sequence users. Multi-User Detection schemes were introduced to detect the users- data in presence of MAI. This paper focuses on linear multi-user detection schemes used for data demodulation. Simulation results depict the performance of three detectors viz-conventional detector, Decorrelating detector and Subspace MMSE (Minimum Mean Square Error) detector. It is seen that the performance of these detectors depends on the number of paths and the length of Gold code used.Keywords: Cross Correlation Matrix, MAI, Multi-UserDetection, Multipath Effect.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21132855 Tissue Composition and Muscularity of Lamb Legs Fed with Sunflower Seeds and Vitamin E
Authors: A. G. Silva Sobrinho, G. M. Manzi, N. L. L. Lima, F. A. Almeida, V. Endo, N. M. B. L. Zeola
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The purpose of this study was to evaluate the tissue composition and carcass muscularity of 32 legs of Ile de France lambs fed with diets containing sunflower seeds and vitamin E, with mean body weight of 15 kg, lodged in individual pens at 15 kg and slaughtered at 32 kg of body weight. The treatments influenced (P<0,05) leg weight, femur length and muscle:bone ratio, being the highest values (2,13 kg, 16,19 cm and 7,38, respectively) in lambs that received diet without sunflower seeds and vitamin E. The other variables were not affected (P>0,05) by the treatments. The interaction of the sunflower and vitamin E was positive for bone total weights and intermuscular fat.Keywords: sheep, conformation, feedlot, nutrition, sugar-cane
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22832854 Evaluation of the Effect of Rotor Solidity on the Performance of a H-Darrieus Turbine Adopting a Blade Element-Momentum Algorithm
Authors: G. Bedon, M. Raciti Castelli, E. Benini
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The present study aims to evaluating the effect of rotor solidity - in terms of chord length for a given rotor diameter - on the performances of a small vertical axis Darrieus wind turbine. The proposed work focuses on both power production and rotor power coefficient, considering also the structural constraints deriving from the centrifugal forces due to rotor angular velocity. Also the smoothness of the resulting power curves have been investigated, in order to evaluate the controllability of the corresponding rotor architectures.Keywords: Vertical axis wind turbine, Darrieus, solidity, Blade Element-Momentum
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 59682853 A Critical Study of Media Profiling on Society-s Social Problems from a British Perspective
Authors: Cj Gletus Matthews Cn Jacobs, Kogilah Narayanasamy
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This article explores the sociological perspectives on social problems and the role of the media which has a delicate role to tread in balancing its duty to the public and the victim Whilst social problems have objective conditions, it is the subjective definition of such problems that ensure which social problem comes to the fore and which doesn-t. Further it explores the roles and functions of policymakers when addressing social problems and the impact of the inception of media profiling as well as the advantages and disadvantages of media profiling towards social problems. It focuses on the inception of media profiling due to its length and a follow up article will explore how current media profiling towards social problems have evolved since its inception.Keywords: Media Profiling, Policy Response, Social Problems
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13222852 3D Numerical Simulation on Annular Diffuser Temperature Distribution Enhancement by Different Twist Arrangement
Authors: Ehan Sabah Shukri, Wirachman Wisnoe
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The influence of twist arrangement on the temperature distribution in an annular diffuser fitted with twisted rectangular hub is investigated. Different pitches (Y = 120 mm, 100 mm, 80 mm, and 60 mm) for the twist arrangements are simulated to be compared. The geometry of the annular diffuser and the inlet condition for the hub arrangements are kept constant. The result reveals that using twisted rectangular hub insert with different pitches will force the temperature to distribute in a circular direction. However, temperature distribution will be enhanced with the length pitch increases.
Keywords: Numerical simulation, twist arrangement, annular diffuser, temperature distribution, swirl flow, pitches.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14732851 Study on Radio Link Availability in Millimeter Wave Range
Authors: Boncho G. Bonev, Kliment N. Angelov, Emil S. Altimirski
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In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth-s atmosphere. Based on statistical rain rates data for Bulgaria, the link availability can be determined, depending on the working frequency, the path length and the Power Budget of the link. For the calculations of rain attenuation and atmosphere-s attenuation the ITU recommendations are used.Keywords: rain attenuation, atmospheric gaseous attenuation, link availability, link breaking probability
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20242850 Optimization of a Triangular Fin with Variable Fin Base Thickness
Authors: Hyung Suk Kang
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A triangular fin with variable fin base thickness is analyzed and optimized using a two-dimensional analytical method. The influence of fin base height and fin base thickness on the temperature in the fin is listed. For the fixed fin volumes, the maximum heat loss, the corresponding optimum fin effectiveness, fin base height and fin tip length as a function of the fin base thickness, convection characteristic number and dimensionless fin volume are represented. One of the results shows that the optimum heat loss increases whereas the corresponding optimum fin effectiveness decreases with the increase of fin volume.Keywords: A triangular fin, Convection characteristic number, Heat loss, Fin base thickness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41232849 Software Evolution Based Sequence Diagrams Merging
Authors: Zine-Eddine Bouras, Abdelouaheb Talai
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The need to merge software artifacts seems inherent to modern software development. Distribution of development over several teams and breaking tasks into smaller, more manageable pieces are an effective means to deal with the kind of complexity. In each case, the separately developed artifacts need to be assembled as efficiently as possible into a consistent whole in which the parts still function as described. In addition, earlier changes are introduced into the life cycle and easier is their management by designers. Interaction-based specifications such as UML sequence diagrams have been found effective in this regard. As a result, sequence diagrams can be used not only for capturing system behaviors but also for merging changes in order to create a new version. The objective of this paper is to suggest a new approach to deal with the problem of software merging at the level of sequence diagrams by using the concept of dependence analysis that captures, formally, all mapping, and differences between elements of sequence diagrams and serves as a key concept to create a new version of sequence diagram.Keywords: System behaviors, sequence diagram merging, dependence analysis, sequence diagram slicing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17622848 Parallel Joint Channel Coding and Cryptography
Authors: Nataša Živić, Christoph Ruland
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Method of Parallel Joint Channel Coding and Cryptography has been analyzed and simulated in this paper. The method is an extension of Soft Input Decryption with feedback, which is used for improvement of channel decoding of secured messages. Parallel Joint Channel Coding and Cryptography results in improved coding gain of channel decoding, which achieves more than 2 dB. Such results are an implication of a combination of receiver components and their interoperability.Keywords: Block length, Coding gain, Feedback, L-values, Parallel Joint Channel Coding and Cryptography, Soft Input Decryption.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15852847 A Small-Scale Knowledge Management System for a Service-Oriented Department
Authors: Eliza Mazmee Mazlan, K.S. Savita, Amir Hamzah Zalfakhar
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This paper demonstrates an effort of a serviceoriented engineering department in improving the sharing and transfer of knowledge. Although the department consist of only six employees, but it provides services in various chemical application in an oil and gas business. The services provided span across Asia Pacific region mainly Indonesia, Myanmar, Vietnam, Brunei, Thailand and Singapore. Currently there are no effective tools or integrated systems that support the sharing or transfer and maintenance of knowledge so the department has considered preserving this valuable knowledge by developing a Knowledge Management System (KMS). This paper presents the development of a KMS to support the sharing of knowledge in a service-oriented engineering department of an oil and gas company. The embedded features in the KMS like blog and forum will encourage iterative process of knowledge sharing among the employees in the department. The information and knowledge being shared, discussed and communicated will be then achieved for future re-use. The re-use of the knowledge allows the department to reduce redundant efforts in providing consistent, up-to-date and cost effective of the best solution to the its clients.Keywords: Knowledge management, knowledge managementsystem, knowledge barrier, knowledge sharing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14632846 The Effect of Slow Variation of Base Flow Profile on the Stability of Slightly Curved Mixing Layers
Authors: Irina Eglite, Andrei A. Kolyshkin
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The effect of small non-parallelism of the base flow on the stability of slightly curved mixing layers is analyzed in the present paper. Assuming that the instability wavelength is much smaller than the length scale of the variation of the base flow we derive an amplitude evolution equation using the method of multiple scales. The proposed asymptotic model provides connection between parallel flow approximations and takes into account slow longitudinal variation of the base flow.Keywords: shallow water, parallel flow assumption, weaklynonlinear analysis, method of multiple scales
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14742845 A Norm-based Approach for Profiling Business Knowledge
Authors: Nazmona Mat Ali, Kecheng Liu
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Knowledge is a key asset for any organisation to sustain competitive advantages, but it is difficult to identify and represent knowledge which is needed to perform activities in business processes. The effective knowledge management and support for relevant business activities definitely gives a huge impact to the performance of the organisation as a whole. This is because that knowledge have the functions of directing, coordinating and controlling actions within business processes. The study has introduced organisational morphology, a norm-based approach by applying semiotic theories which emphasise on the representation of knowledge in norms. This approach is concerned with the identification of activities into three categories: substantive, communication and control activities. All activities are directed by norms; hence three types of norms exist; each is associated to a category of activities. The paper describes the approach briefly and illustrates the application of this approach through a case study of academic activities in higher education institutions. The result of the study shows that the approach provides an effective way to profile business knowledge and the profile enables the understanding and specification of business requirements of an organisation.Keywords: Business knowledge, Business process, Norms, Semiotics, Organisational morphology
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15692844 Ultrasound Mechanical Index as a Parameter Affecting of the Ability of Proliferation of Cells
Authors: Z. Hormozi Moghaddam, M. Mokhtari-Dizaji, M. Movahedin, M. E. Ravari
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Mechanical index (MI) is used for quantifying acoustic cavitation and the relationship between acoustic pressure and the frequency. In this study, modeling of the MI was applied to provide treatment protocol and to understand the effective physical processes on reproducibility of stem cells. The acoustic pressure and MI equations are modeled and solved to estimate optimal MI for 28, 40, 150 kHz and 1 MHz frequencies. Radial and axial acoustic pressure distribution was extracted. To validate the results of the modeling, the acoustic pressure in the water and near field depth was measured by a piston hydrophone. Results of modeling and experiments show that the model is consistent well to experimental results with 0.91 and 0.90 correlation of coefficient (p<0.05) for 1 MHz and 40 kHz. Low intensity ultrasound with 0.40 MI is more effective on the proliferation rate of the spermatogonial stem cells during the seven days of culture, in contrast, high MI has a harmful effect on the spermatogonial stem cells. This model provides proper treatment planning in vitro and in vivo by estimating the cavitation phenomenon.
Keywords: Ultrasound, mechanical index, modeling, stem cell.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9612843 Cyclic Heating Effect on Hardness of Copper
Authors: Tahany W. Sadak
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Presented work discusses research results concerning the effect of the heat treatment process. Thermal fatigue which expresses repeated heating and cooling processes affect the ductility or the brittleness of the material. In this research, 70 specimens of copper (1.5 mm thickness, 85 mm length, 32 mm width) are subjected to thermal fatigue at different conditions. Heating temperatures Th are 100, 300 and 500 °C. Number of repeated cycles N is from 1 to 100. Heating time th =600 Sec, and Cooling time; tC= 900 Sec. Results are evaluated and then compared to each other and to that of specimens without subjected to thermal fatigue.Keywords: Copper, hardness, heat treatment, thermal fatigue, thermal analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12352842 Impact of Moderating Role of e-Administration on Training, Perfromance Appraisal and Organizational Performance
Authors: Ejaz Ali, Muhammad Younas, Tahir Saeed
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In this age of information technology, organizations are revisiting their approach in great deal. E-administration is the most popular area to proceed with. Organizations in order to excel over their competitors are spending a substantial chunk of its resources on E-Administration as it is the most effective, transparent and efficient way to achieve their short term as well as long term organizational goals. E-administration being a tool of ICT plays a significant role towards effective management of HR practices resulting into optimal performance of an organization. The present research was carried out to analyze the impact of moderating role of e-administration in the relationships training and performance appraisal aligned with perceived organizational performance. The study is based on RBV and AMO theories, advocating that use of latest technology in execution of human resource (HR) functions enables an organization to achieve and sustain competitive advantage which leads to optimal firm performance.Keywords: Human resource management, HR function, e-administration, performance appraisal, training, organizational performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11752841 Enhanced Gram-Schmidt Process for Improving the Stability in Signal and Image Processing
Authors: Mario Mastriani, Marcelo Naiouf
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The Gram-Schmidt Process (GSP) is used to convert a non-orthogonal basis (a set of linearly independent vectors) into an orthonormal basis (a set of orthogonal, unit-length vectors). The process consists of taking each vector and then subtracting the elements in common with the previous vectors. This paper introduces an Enhanced version of the Gram-Schmidt Process (EGSP) with inverse, which is useful for signal and image processing applications.
Keywords: Digital filters, digital signal and image processing, Gram-Schmidt Process, orthonormalization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28852840 Effect of Spatially Correlated Disorder on Electronic Transport Properties of Aperiodic Superlattices (GaAs/AlxGa1-xAs)
Authors: F. Bendahma, S. Bentata, S. Cherid, A. Zitouni, S. Terkhi, T. Lantri, Y. Sefir, Z. F. Meghoufel
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We examine the electronic transport properties in AlxGa1-xAs/GaAs superlattices. Using the transfer-matrix technique and the exact Airy function formalism, we investigate theoretically the effect of structural parameters on the electronic energy spectra of trimer thickness barrier (TTB). Our numerical calculations showed that the localization length of the states becomes more extended when the disorder is correlated (trimer case). We have also found that the resonant tunneling time (RTT) is of the order of several femtoseconds.
Keywords: Electronic transport properties, structural parameters, superlattice, transfer-matrix technique.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9522839 Fabrication and Characterization of Poly-Si Vertical Nanowire Thin Film Transistor
Authors: N. Shen, T. T. Le, H. Y. Yu, Z. X. Chen, K. T. Win, N. Singh, G. Q. Lo, D. -L. Kwong
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In this paper, we present a vertical nanowire thin film transistor with gate-all-around architecture, fabricated using CMOS compatible processes. A novel method of fabricating polysilicon vertical nanowires of diameter as small as 30 nm using wet-etch is presented. Both n-type and p-type vertical poly-silicon nanowire transistors exhibit superior electrical characteristics as compared to planar devices. On a poly-crystalline nanowire of 30 nm diameter, high Ion/Ioff ratio of 106, low drain-induced barrier lowering (DIBL) of 50 mV/V, and low sub-threshold slope SS~100mV/dec are demonstrated for a device with channel length of 100 nm.
Keywords: Nanowire (NW), Gate-all-around (GAA), polysilicon (poly-Si), thin-film transistor (TFT).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21922838 Aircraft Supplier Selection Process with Fuzzy Proximity Measure Method using Multiple Criteria Group Decision Making Analysis
Authors: C. Ardil
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Being effective in every organizational activity has become necessary due to the escalating level of competition in all areas of corporate life. In the context of supply chain management, aircraft supplier selection is currently one of the most crucial activities. It is possible to choose the best aircraft supplier and deliver efficiency in terms of cost, quality, delivery time, economic status, and institutionalization if a systematic supplier selection approach is used. In this study, an effective multiple criteria decision-making methodology, proximity measure method (PMM), is used within a fuzzy environment based on the vague structure of the real working environment. The best appropriate aircraft suppliers are identified and ranked after the proposed multiple criteria decision making technique is used in a real-life scenario.
Keywords: Aircraft supplier selection, multiple criteria decision making, fuzzy sets, proximity measure method, Minkowski distance family function, Hausdorff distance function, PMM, MCDM
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3442837 Linking OpenCourseWares and Open Education Resources: Creating an Effective Search and Recommendation System
Authors: Brett E. Shelton, Joel Duffin, Yuxuan Wang, Justin Ball
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With a growing number of digital libraries and other open education repositories being made available throughout the world, effective search and retrieval tools are necessary to access the desired materials that surpass the effectiveness of traditional, allinclusive search engines. This paper discusses the design and use of Folksemantic, a platform that integrates OpenCourseWare search, Open Educational Resource recommendations, and social network functionality into a single open source project. The paper describes how the system was originally envisioned, its goals for users, and data that provides insight into how it is actually being used. Data sources include website click-through data, query logs, web server log files and user account data. Based on a descriptive analysis of its current use, modifications to the platform's design are recommended to better address goals of the system, along with recommendations for additional phases of research.Keywords: Digital libraries, open education, recommendation system, social networks
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22002836 Is the Liberalization Policy Effective on Improving the Bivariate Cointegration of Current Accounts, Foreign Exchange, Stock Prices? Further Evidence from Asian Markets
Authors: Chen-Yin Kuo
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This paper fist examines three set of bivariate cointegrations between any two of current accounts, stock markets, and currency exchange markets in ten Asian countries. Furthermore, we examined the effect of country characters on this bivariate cointegration. Our findings suggest that for three sets of cointegration test, each sample country at least exists one cointegration. India consistently exhibited a bi-directional causal relationship between any two of three indicators. Unlike Pan et al. (2007) and Phylaktis and Ravazzolo (2005), we found that such cointegration is influenced by three characteristics: capital control; flexibility in foreign exchange rates; and the ratio of trade to GDP. These characteristics are the result of liberalization in each Asian country. This implies that liberalization policies are effective on improving the cointegration between any two of financial markets and current account for ten Asian countries.
Keywords: Current account, stock price, foreign exchange rate, country characteristics, bivariate cointegration, bi-directional causal relationships.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14712835 Application of Fluorescent Pseudomonads Inoculant Formulations on Vigna mungo through Field Trial
Authors: Sarma. M.V.R.K, Saharan. K, Prakash. A, Bisaria. V. S, Sahai.V
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Vermiculite was used to develop inorganic carrier-based formulations of fluorescent pseudomonad strains R62 and R81. The effect of bio-inoculation of fluorescent pseudomonad strains R62 and R81 (plant growth promoting and biocontrol agent) on growth responses of Vigna-mungo under field condition was enumerated. The combined bioinoculation of these two organisms in a formuation increased the pods yield by 300% in comparison to the control crop. There was also significant increment in the other plant growth responses such as dry root weight, dry shoot weight, shoot length and number of branches per plant.Keywords: Bio-inoculants formulation, Fluorescent pseudomonad, Plant growth promotion activity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20502834 Financial Portfolio Optimization in Electricity Markets: Evaluation via Sharpe Ratio
Authors: F. Gökgöz, M. E. Atmaca
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Electricity plays an indispensable role in human life and the economy. It is a unique product or service that must be balanced instantaneously, as electricity is not stored, generation and consumption should be proportional. Effective and efficient use of electricity is very important not only for society, but also for the environment. A competitive electricity market is one of the best ways to provide a suitable platform for effective and efficient use of electricity. On the other hand, it carries some risks that should be carefully managed by the market players. Risk management is an essential part in market players’ decision making. In this paper, risk management through diversification is applied with the help of Markowitz’s Mean-variance, Down-side and Semi-variance methods for a case study. Performance of optimal electricity sale solutions are measured and evaluated via Sharpe-Ratio, and the optimal portfolio solutions are improved. Two years of historical weekdays’ price data of the Turkish Day Ahead Market are used to demonstrate the approach.
Keywords: Electricity market, portfolio optimization, risk management in electricity market, Sharpe ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14852833 Work-Related Shoulder Lesions and Labor Lawsuits in Brazil: Cross-Sectional Study on Worker Health Actions Developed by Employers
Authors: Reinaldo Biscaro, Luciano R. Ferreira, Leonardo C. Biscaro, Raphael C. Biscaro, Isabela S. Vasconcelos, Laura C. R. Ferreira, Cristiano M. Galhardi, Erica P. Baciuk
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Introduction: The present study had the objective to present the profile of workers with shoulder disorders related to labor lawsuits in Brazil. The study analyzed the association between the worker’s health and the actions performed by the companies related to injured professional. The research method performed a retrospective, cross-sectional and quantitative database analysis. The documents of labor lawsuits with shoulder injury registered at the Regional Labor Court in the 15th region (Campinas - São Paulo) were submitted to the medical examination and evaluated during the period from 2012 until 2015. The data collected were age, gender, onset of symptoms, length of service, current occupation, type of shoulder injury, referred complaints, type of acromion, associated or related diseases, company actions as CAT (workplace accident communication), compliance of NR7 by the organization (Environmental Risk Prevention Program - PPRA and Medical Coordination Program in Occupational Health - PCMSO). Results: From the 93 workers evaluated, there was a prevalence of men (58.1%), with a mean age of 42.6 y-o, and 54.8% were included in the age group 35-49 years. Regarding the length of work time in the company, 66.7% have worked for more than 5 years. There was an association between gender and current occupational status (p < 0.005), with predominance of women in household occupation (13 vs. 2) and predominance of unemployed men in job search situation (24 vs. 10) and reintegrated to work by judicial decision (8 vs. 2). There was also a correlation between pain and functional limitation (p < 0.01). There was a positive association of PPRA with the complaint of functional limitation and negative association with pain (p < 0.04). There was also a correlation between the sedentary lifestyle and the presence of PCMSO and PPRA (p < 0.04), and the absence of CAT in the companies (p < 0.001). It was concluded that the appearance or aggravation of osseous and articular shoulder pathologies in workers who have undertaken labor law suits seem to be associated with individual habits or inadequate labor practices. These data can help preventing the occurrence of these lesions by implementing local health promotion policies at work.Keywords: Work-related accidents, cross-sectional study, shoulder lesions, labor lawsuits.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9002832 Modal Propagation Properties of Elliptical Core Optical Fibers Considering Stress-Optic Effects
Authors: M. Shah Alam, Sarkar Rahat M. Anwar
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The effect of thermally induced stress on the modal properties of highly elliptical core optical fibers is studied in this work using a finite element method. The stress analysis is carried out and anisotropic refractive index change is calculated using both the conventional plane strain approximation and the generalized plane strain approach. After considering the stress optical effect, the modal analysis of the fiber is performed to obtain the solutions of fundamental and higher order modes. The modal effective index, modal birefringence, group effective index, group birefringence, and dispersion of different modes of the fiber are presented. For propagation properties, it can be seen that the results depend much on the approach of stress analysis.Keywords: Birefringence, dispersion, elliptical core fiber, optical mode analysis, stress-optic effect, stress analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22902831 Density Functional Calculations of 27Al, 11B,and 14N and NQR Parameters in the (6, 0) BN_AlN Nanotube Junction
Authors: Morteza Farahani, Ahmad Seif, Asadallah Boshra, Hossein Aghaie
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Density functional theory (DFT) calculations were performed to calculate aluminum-27, boron-11, and nitrogen-14 quadrupole coupling constant (CQ) in the representative considered model of (6, 0) boron nitride-aluminum nitride nanotube junction (BN-AlNNT) for the first time. To this aim, 1.3 nm length of BNAlN consisting of 18 Al, 18 B, and 36 N atoms was selected where the end atoms capped by hydrogen atoms. The calculated CQ values for optimized BN-AlNNT system reveal different electrostatic environment in the mentioned system. The calculations were performed using the Gaussian 98 package of program.
Keywords: Nanotube Junction, Density functional, Nuclear Quadrupole Resonance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17212830 Text Mining of Twitter Data Using a Latent Dirichlet Allocation Topic Model and Sentiment Analysis
Authors: Sidi Yang, Haiyi Zhang
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Twitter is a microblogging platform, where millions of users daily share their attitudes, views, and opinions. Using a probabilistic Latent Dirichlet Allocation (LDA) topic model to discern the most popular topics in the Twitter data is an effective way to analyze a large set of tweets to find a set of topics in a computationally efficient manner. Sentiment analysis provides an effective method to show the emotions and sentiments found in each tweet and an efficient way to summarize the results in a manner that is clearly understood. The primary goal of this paper is to explore text mining, extract and analyze useful information from unstructured text using two approaches: LDA topic modelling and sentiment analysis by examining Twitter plain text data in English. These two methods allow people to dig data more effectively and efficiently. LDA topic model and sentiment analysis can also be applied to provide insight views in business and scientific fields.
Keywords: Text mining, Twitter, topic model, sentiment analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18082829 Static Modeling of the Delamination of a Composite Material Laminate in Mode II
Authors: Y. Madani, H. Achache, B. Boutabout
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The purpose of this paper is to analyze numerically by the three-dimensional finite element method, using ABAQUS calculation code, the mechanical behavior of a unidirectional and multidirectional delaminated stratified composite under mechanical loading in Mode II. This study consists of the determination of the energy release rate G in mode II as well as the distribution of equivalent von Mises stresses along the damaged zone by varying several parameters such as the applied load and the delamination length. It allowed us to deduce that the high energy release rate favors delamination at the free edges of a stratified plate subjected to bending.
Keywords: Delamination, energy release rate, finite element method, stratified composite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7092828 Financial Portfolio Optimization in Turkish Electricity Market via Value at Risk
Authors: F. Gökgöz, M. E. Atmaca
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Electricity has an indispensable role in human daily life, technological development and economy. It is a special product or service that should be instantaneously generated and consumed. Sources of the world are limited so that effective and efficient use of them is very important not only for human life and environment but also for technological and economic development. Competitive electricity market is one of the important way that provides suitable platform for effective and efficient use of electricity. Besides benefits, it brings along some risks that should be carefully managed by a market player like Electricity Generation Company. Risk management is an essential part in market players’ decision making. In this paper, risk management through diversification is applied with the help of Value at Risk methods for case studies. Performance of optimal electricity sale solutions are measured and the portfolio performance has been evaluated via Sharpe-Ratio, and compared with conventional approach. Biennial historical electricity price data of Turkish Day Ahead Market are used to demonstrate the approach.Keywords: Electricity market, portfolio optimization, risk management, Sharpe ratio, value at risk.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10522827 Image Retrieval Based on Multi-Feature Fusion for Heterogeneous Image Databases
Authors: N. W. U. D. Chathurani, Shlomo Geva, Vinod Chandran, Proboda Rajapaksha
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Selecting an appropriate image representation is the most important factor in implementing an effective Content-Based Image Retrieval (CBIR) system. This paper presents a multi-feature fusion approach for efficient CBIR, based on the distance distribution of features and relative feature weights at the time of query processing. It is a simple yet effective approach, which is free from the effect of features' dimensions, ranges, internal feature normalization and the distance measure. This approach can easily be adopted in any feature combination to improve retrieval quality. The proposed approach is empirically evaluated using two benchmark datasets for image classification (a subset of the Corel dataset and Oliva and Torralba) and compared with existing approaches. The performance of the proposed approach is confirmed with the significantly improved performance in comparison with the independently evaluated baseline of the previously proposed feature fusion approaches.
Keywords: Feature fusion, image retrieval, membership function, normalization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1345