Search results for: interpretive structural modeling
4154 The Distributed Pattern of the Neurovascular Structures under Clavicle to Minimize Structural Injury in Clinical Field: Anatomical Study
Authors: Anna Jeon, Seung-Ho Han, Je-Hun Lee
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The aim of this study was to determine the location and distribution pattern of neurovascular structures superior and inferior to the clavicle by detailed dissection. Fifteen adult non-embalmed cadavers with a mean age of 71.5 years were studied. For measurements, the most prominent point of the sternal end of the clavicle (SEC) on anterior view and the most prominent point of the acromial end of the clavicle (AEC) were identified before dissection. A line connecting the SEC and AEC was used as a reference line. The surrounding neurovascular structures were investigated. The supraclavicular nerve was densely distributed at 71.73% on the reference line. Branches of the thoracoacromial artery were located at 76.92%. Branches of subclavian vein were evenly distributed at all sections. The subclavian vein and artery and brachial plexus were located from 31.3% to 57.5%. That area needs caution because major neurovascular structures run underneath the clavicle.Keywords: clavicle, ORIF, neurovascular structure, anatomical study
Procedia PDF Downloads 1664153 A Knowledge-As-A-Service Support Framework for Ambient Learning in Kenya
Authors: Lucy W. Mburu, Richard Karanja, Simon N. Mwendia
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Over recent years, learners have experienced a constant need to access on demand knowledge that is fully aligned with the paradigm of cloud computing. As motivated by the global sustainable development goal to ensure inclusive and equitable learning opportunities, this research has developed a framework hinged on the knowledge-as-a-service architecture that utilizes knowledge from ambient learning systems. Through statistical analysis and decision tree modeling, the study discovers influential variables for ambient learning among university students. The main aim is to generate a platform for disseminating and exploiting the available knowledge to aid the learning process and, thus, to improve educational support on the ambient learning system. The research further explores how collaborative effort can be used to form a knowledge network that allows access to heterogeneous sources of knowledge, which benefits knowledge consumers, such as the developers of ambient learning systems.Keywords: actionable knowledge, ambient learning, cloud computing, decision trees, knowledge as a service
Procedia PDF Downloads 1604152 A Time-Varying and Non-Stationary Convolution Spectral Mixture Kernel for Gaussian Process
Authors: Kai Chen, Shuguang Cui, Feng Yin
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Gaussian process (GP) with spectral mixture (SM) kernel demonstrates flexible non-parametric Bayesian learning ability in modeling unknown function. In this work a novel time-varying and non-stationary convolution spectral mixture (TN-CSM) kernel with a significant enhancing of interpretability by using process convolution is introduced. A way decomposing the SM component into an auto-convolution of base SM component and parameterizing it to be input dependent is outlined. Smoothly, performing a convolution between two base SM component yields a novel structure of non-stationary SM component with much better generalized expression and interpretation. The TN-CSM perfectly allows compatibility with the stationary SM kernel in terms of kernel form and spectral base ignored and confused by previous non-stationary kernels. On synthetic and real-world datatsets, experiments show the time-varying characteristics of hyper-parameters in TN-CSM and compare the learning performance of TN-CSM with popular and representative non-stationary GP.Keywords: Gaussian process, spectral mixture, non-stationary, convolution
Procedia PDF Downloads 1964151 Shock Compressibility of Iron Alloys Calculated in the Framework of Quantum-Statistical Models
Authors: Maxim A. Kadatskiy, Konstantin V. Khishchenko
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Iron alloys are widespread components in various types of structural materials which are exposed to intensive thermal and mechanical loads. Various quantum-statistical cell models with the approximation of self-consistent field can be used for the prediction of the behavior of these materials under extreme conditions. The application of these models is even more valid, the higher the temperature and the density of matter. Results of Hugoniot calculation for iron alloys in the framework of three quantum-statistical (the Thomas–Fermi, the Thomas–Fermi with quantum and exchange corrections and the Hartree–Fock–Slater) models are presented. Results of quantum-statistical calculations are compared with results from other reliable models and available experimental data. It is revealed a good agreement between results of calculation and experimental data for terra pascal pressures. Advantages and disadvantages of this approach are shown.Keywords: alloy, Hugoniot, iron, terapascal pressure
Procedia PDF Downloads 3424150 Expected Present Value of Losses in the Computation of Optimum Seismic Design Parameters
Authors: J. García-Pérez
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An approach to compute optimum seismic design parameters is presented. It is based on the optimization of the expected present value of the total cost, which includes the initial cost of structures as well as the cost due to earthquakes. Different types of seismicity models are considered, including one for characteristic earthquakes. Uncertainties are included in some variables to observe the influence on optimum values. Optimum seismic design coefficients are computed for three different structural types representing high, medium and low rise buildings, located near and far from the seismic sources. Ordinary and important structures are considered in the analysis. The results of optimum values show an important influence of seismicity models as well as of uncertainties on the variables.Keywords: importance factors, optimum parameters, seismic losses, seismic risk, total cost
Procedia PDF Downloads 2854149 Analysis of Electricity Demand at Household Level Using Leap Model in Balochistan, Pakistan
Authors: Sheikh Saeed Ahmad
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Electricity is vital for any state’s development that needs policy for planning the power network extension. This study is about simulation modeling for electricity in Balochistan province. Baseline data of electricity consumption was used of year 2004 and projected with the help of LEAP model up to subsequent 30 years. Three scenarios were created to run software. One scenario was baseline and other two were alternative or green scenarios i.e. solar and wind energy scenarios. Present study revealed that Balochistan has much greater potential for solar and wind energy for electricity production. By adopting these alternative energy forms, Balochistan can save energy in future nearly 23 and 48% by incorporating solar and wind power respectively. Thus, the study suggests to government planners, an aspect of integrating renewable sources in power system for ensuring sustainable development and growth.Keywords: demand and supply, LEAP, solar energy, wind energy, households
Procedia PDF Downloads 4274148 Modelling the Indonesian Goverment Securities Yield Curve Using Nelson-Siegel-Svensson and Support Vector Regression
Authors: Jamilatuzzahro, Rezzy Eko Caraka
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The yield curve is the plot of the yield to maturity of zero-coupon bonds against maturity. In practice, the yield curve is not observed but must be extracted from observed bond prices for a set of (usually) incomplete maturities. There exist many methodologies and theory to analyze of yield curve. We use two methods (the Nelson-Siegel Method, the Svensson Method, and the SVR method) in order to construct and compare our zero-coupon yield curves. The objectives of this research were: (i) to study the adequacy of NSS model and SVR to Indonesian government bonds data, (ii) to choose the best optimization or estimation method for NSS model and SVR. To obtain that objective, this research was done by the following steps: data preparation, cleaning or filtering data, modeling, and model evaluation.Keywords: support vector regression, Nelson-Siegel-Svensson, yield curve, Indonesian government
Procedia PDF Downloads 2454147 Temperature Effect on Sound Propagation in an Elastic Pipe with Viscoelastic Liquid
Authors: S. Levitsky, R. Bergman
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Fluid rheology may have essential impact on sound propagation in a liquid-filled pipe, especially, in a low frequency range. Rheological parameters of liquid are temperature-sensitive, which ultimately results in a temperature dependence of the wave speed and attenuation in the waveguide. The study is devoted to modeling of this effect at sound propagation in an elastic pipe with polymeric liquid, described by generalized Maxwell model with non-zero high-frequency viscosity. It is assumed that relaxation spectrum is distributed according to the Spriggs law; temperature impact on the liquid rheology is described on the basis of the temperature-superposition principle and activation theory. The dispersion equation for the waveguide, considered as a thin-walled tube with polymeric solution, is obtained within a quasi-one-dimensional formulation. Results of the study illustrate the influence of temperature on sound propagation in the system.Keywords: elastic tube, sound propagation, temperature effect, viscoelastic liquid
Procedia PDF Downloads 4204146 A Heuristic Approach for the General Flowshop Scheduling Problem to Minimize the Makespan
Authors: Mohsen Ziaee
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Almost all existing researches on the flowshop scheduling problems focus on the permutation schedules and there is insufficient study dedicated to the general flowshop scheduling problems in the literature, since the modeling and solving of the general flowshop scheduling problems are more difficult than the permutation ones, especially for the large-size problem instances. This paper considers the general flowshop scheduling problem with the objective function of the makespan (F//Cmax). We first find the optimal solution of the problem by solving a mixed integer linear programming model. An efficient heuristic method is then presented to solve the problem. An ant colony optimization algorithm is also proposed for the problem. In order to evaluate the performance of the methods, computational experiments are designed and performed. Numerical results show that the heuristic algorithm can result in reasonable solutions with low computational effort and even achieve optimal solutions in some cases.Keywords: scheduling, general flow shop scheduling problem, makespan, heuristic
Procedia PDF Downloads 2074145 Continuum-Based Modelling Approaches for Cell Mechanics
Authors: Yogesh D. Bansod, Jiri Bursa
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The quantitative study of cell mechanics is of paramount interest since it regulates the behavior of the living cells in response to the myriad of extracellular and intracellular mechanical stimuli. The novel experimental techniques together with robust computational approaches have given rise to new theories and models, which describe cell mechanics as a combination of biomechanical and biochemical processes. This review paper encapsulates the existing continuum-based computational approaches that have been developed for interpreting the mechanical responses of living cells under different loading and boundary conditions. The salient features and drawbacks of each model are discussed from both structural and biological points of view. This discussion can contribute to the development of even more precise and realistic computational models of cell mechanics based on continuum approaches or on their combination with microstructural approaches, which in turn may provide a better understanding of mechanotransduction in living cells.Keywords: cell mechanics, computational models, continuum approach, mechanical models
Procedia PDF Downloads 3634144 Compressible Flow Modeling in Pipes and Porous Media during Blowdown Experiment
Authors: Thomas Paris, Vincent Bruyere, Patrick Namy
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A numerical model is developed to simulate gas blowdowns through a thin tube and a filter (porous media), separating a high pressure gas filled reservoir to low pressure ones. Based on a previous work, a one-dimensional approach is developed by using the finite element method to solve the transient compressible flow and to predict the pressure and temperature evolution in space and time. Mass, momentum, and energy conservation equations are solved in a fully coupled way in the reservoirs, the pipes and the porous media. Numerical results, such as pressure and temperature evolutions, are firstly compared with experimental data to validate the model for different configurations. Couplings between porous media and pipe flow are then validated by checking mass balance. The influence of the porous media and the nature of the gas is then studied for different initial high pressure values.Keywords: compressible flow, fluid mechanics, heat transfer, porous media
Procedia PDF Downloads 4064143 Radar Signal Detection Using Neural Networks in Log-Normal Clutter for Multiple Targets Situations
Authors: Boudemagh Naime
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Automatic radar detection requires some methods of adapting to variations in the background clutter in order to control their false alarm rate. The problem becomes more complicated in non-Gaussian environment. In fact, the conventional approach in real time applications requires a complex statistical modeling and much computational operations. To overcome these constraints, we propose another approach based on artificial neural network (ANN-CMLD-CFAR) using a Back Propagation (BP) training algorithm. The considered environment follows a log-normal distribution in the presence of multiple Rayleigh-targets. To evaluate the performances of the considered detector, several situations, such as scale parameter and the number of interferes targets, have been investigated. The simulation results show that the ANN-CMLD-CFAR processor outperforms the conventional statistical one.Keywords: radat detection, ANN-CMLD-CFAR, log-normal clutter, statistical modelling
Procedia PDF Downloads 3644142 Study of Electroless Co-P Deposits on Steel
Authors: K. Chouchane, R. Mehdaoui, A. Atmani, A. Merati
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A Co-P layer was coated onto steel substrate using electroless plating method in alkaline media. Three temperatures were tested 70, 80 and 90 °C. Sodium hypophosphite was used as a reducer. The influence of addition of boric acid in the bath on deposits properties was studied. Different techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and hardness measures were employed to characterize the morphology, composition and the structural properties of the resulting films. The corrosion properties of the prepared coatings were tested in 3% NaCl media, by means of current-potential curves, potential transients. The results showed that the thickness increase with increasing of bath temperature. The addition of boric acid don’t affect the thickness but has an influence on hardness. In fact, the hardness increases from 500 to 700Hv for the temperature of 90°C. The corrosion resistance is improved for all prepared layers.Keywords: cobalt deposits, corrosion, electroless deposition, hardness
Procedia PDF Downloads 2064141 Searching the Relationship among Components that Contribute to Interactive Plight and Educational Execution
Authors: Shri Krishna Mishra
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In an educational context, technology can prompt interactive plight only when it is used in conjunction with interactive plight methods. This study, therefore, examines the relationships among components that contribute to higher levels of interactive plight and execution, such as interactive Plight methods, technology, intrinsic motivation and deep learning. 526 students participated in this study. With structural equation modelling, the authors test the conceptual model and identify satisfactory model fit. The results indicate that interactive Plight methods, technology and intrinsic motivation have significant relationship with interactive Plight; deep learning mediates the relationships of the other variables with Execution.Keywords: searching the relationship among components, contribute to interactive plight, educational execution, intrinsic motivation
Procedia PDF Downloads 4544140 Steel Concrete Composite Bridge: Modelling Approach and Analysis
Authors: Kaviyarasan D., Satish Kumar S. R.
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India being vast in area and population with great scope of international business, roadways and railways network connection within the country is expected to have a big growth. There are numerous rail-cum-road bridges constructed across many major rivers in India and few are getting very old. So there is more possibility of repairing or coming up with such new bridges in India. Analysis and design of such bridges are practiced through conventional procedure and end up with heavy and uneconomical sections. Such heavy class steel bridges when subjected to high seismic shaking has more chance to fail by stability because the members are too much rigid and stocky rather than being flexible to dissipate the energy. This work is the collective study of the researches done in the truss bridge and steel concrete composite truss bridges presenting the method of analysis, tools for numerical and analytical modeling which evaluates its seismic behaviour and collapse mechanisms. To ascertain the inelastic and nonlinear behaviour of the structure, generally at research level static pushover analysis is adopted. Though the static pushover analysis is now extensively used for the framed steel and concrete buildings to study its lateral action behaviour, those findings by pushover analysis done for the buildings cannot directly be used for the bridges as such, because the bridges have completely a different performance requirement, behaviour and typology as compared to that of the buildings. Long span steel bridges are mostly the truss bridges. Truss bridges being formed by many members and connections, the failure of the system does not happen suddenly with single event or failure of one member. Failure usually initiates from one member and progresses gradually to the next member and so on when subjected to further loading. This kind of progressive collapse of the truss bridge structure is dependent on many factors, in which the live load distribution and span to length ratio are most significant. The ultimate collapse is anyhow by the buckling of the compression members only. For regular bridges, single step pushover analysis gives results closer to that of the non-linear dynamic analysis. But for a complicated bridge like heavy class steel bridge or the skewed bridges or complicated dynamic behaviour bridges, nonlinear analysis capturing the progressive yielding and collapse pattern is mandatory. With the knowledge of the postelastic behaviour of the bridge and advancements in the computational facility, the current level of analysis and design of bridges has moved to state of ascertaining the performance levels of the bridges based on the damage caused by seismic shaking. This is because the buildings performance levels deals much with the life safety and collapse prevention levels, whereas the bridges mostly deal with the extent damages and how quick it can be repaired with or without disturbing the traffic after a strong earthquake event. The paper would compile the wide spectrum of modeling to analysis of the steel concrete composite truss bridges in general.Keywords: bridge engineering, performance based design of steel truss bridge, seismic design of composite bridge, steel-concrete composite bridge
Procedia PDF Downloads 1854139 Heat and Radiation Influence on Granite-Galena Concrete for Nuclear Shielding Applications
Authors: Mohamed A. Safan, Walid Khalil, Amro Fathalla
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Advances in concrete technology and implementation of new materials made it possible to produce special types of concrete for different structural applications. In this research, granite and galena were incorporated in different concrete mixes to obtain high performance concrete for shielding against gamma radiations in nuclear facilities. Chemically prepared industrial galena was used to replace different volume fractions of the fine aggregate. The test specimens were exposed to different conditions of heating cycles and irradiation. The exposed specimens and counterpart unexposed specimens were tested to evaluate the density, the compressive strength and the attenuation coefficient. The proposed mixes incorporating galena showed better performance in terms of compressive strength and gamma attenuation capacity, especially after the exposure to different heating cycles.Keywords: concrete, galena, shielding, attenuation, radiation
Procedia PDF Downloads 4604138 Application of Unstructured Mesh Modeling in Evolving SGE of an Airport at the Confluence of Multiple Rivers in a Macro Tidal Region
Authors: A. A. Purohit, M. M. Vaidya, M. D. Kudale
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Among the various developing countries in the world like China, Malaysia, Korea etc., India is also developing its infrastructures in the form of Road/Rail/Airports and Waterborne facilities at an exponential rate. Mumbai, the financial epicenter of India is overcrowded and to relieve the pressure of congestion, Navi Mumbai suburb is being developed on the east bank of Thane creek near Mumbai. The government due to limited space at existing Mumbai Airports (domestic and international) to cater for the future demand of airborne traffic, proposes to build a new international airport near Panvel at Navi Mumbai. Considering the precedence of extreme rainfall on 26th July 2005 and nearby townships being in a low-lying area, wherein new airport is proposed, it is inevitable to study this complex confluence area from a hydrodynamic consideration under both tidal and extreme events (predicted discharge hydrographs), to avoid inundation of the surrounding due to the proposed airport reclamation (1160 hectares) and to determine the safe grade elevation (SGE). The model studies conducted using the application of unstructured mesh to simulate the Panvel estuarine area (93 km2), calibration, validation of a model for hydraulic field measurements and determine the maxima water levels around the airport for various extreme hydrodynamic events, namely the simultaneous occurrence of highest tide from the Arabian Sea and peak flood discharges (Probable Maximum Precipitation and 26th July 2005) from five rivers, the Gadhi, Kalundri, Taloja, Kasadi and Ulwe, meeting at the proposed airport area revealed that: (a) The Ulwe River flowing beneath the proposed airport needs to be diverted. The 120m wide proposed Ulwe diversion channel having a wider base width of 200 m at SH-54 Bridge on the Ulwe River along with the removal of the existing bund in Moha Creek is inevitable to keep the SGE of the airport to a minimum. (b) The clear waterway of 80 m at SH-54 Bridge (Ulwe River) and 120 m at Amra Marg Bridge near Moha Creek is also essential for the Ulwe diversion and (c) The river bank protection works on the right bank of Gadhi River between the NH-4B and SH-54 bridges as well as upstream of the Ulwe River diversion channel are essential to avoid inundation of low lying areas. The maxima water levels predicted around the airport keeps SGE to a minimum of 11m with respect to Chart datum of Ulwe Bundar and thus development is not only technologically-economically feasible but also sustainable. The unstructured mesh modeling is a promising tool to simulate complex extreme hydrodynamic events and provides a reliable solution to evolve optimal SGE of airport.Keywords: airport, hydrodynamics, safe grade elevation, tides
Procedia PDF Downloads 2614137 Sentiment Analysis on University Students’ Evaluation of Teaching and Their Emotional Engagement
Authors: Elisa Santana-Monagas, Juan L. Núñez, Jaime León, Samuel Falcón, Celia Fernández, Rocío P. Solís
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Teaching practices have been widely studied in relation to students' outcomes, positioning themselves as one of their strongest catalysts and influencing students' emotional experiences. In the higher education context, teachers become even more crucial as many students ground their decisions on which courses to enroll in based on opinions and ratings of teachers from other students. Unfortunately, sometimes universities do not provide the personal, social, and academic stimulation students demand to be actively engaged. To evaluate their teachers, universities often rely on students' evaluations of teaching (SET) collected via Likert scale surveys. Despite its usefulness, such a method has been questioned in terms of validity and reliability. Alternatively, researchers can rely on qualitative answers to open-ended questions. However, the unstructured nature of the answers and a large amount of information obtained requires an overwhelming amount of work. The present work presents an alternative approach to analyse such data: sentiment analysis. To the best of our knowledge, no research before has included results from SA into an explanatory model to test how students' sentiments affect their emotional engagement in class. The sample of the present study included a total of 225 university students (Mean age = 26.16, SD = 7.4, 78.7 % women) from the Educational Sciences faculty of a public university in Spain. Data collection took place during the academic year 2021-2022. Students accessed an online questionnaire using a QR code. They were asked to answer the following open-ended question: "If you had to explain to a peer who doesn't know your teacher how he or she communicates in class, what would you tell them?". Sentiment analysis was performed using Microsoft's pre-trained model. The reliability of the measure was estimated between the tool and one of the researchers who coded all answers independently. The Cohen's kappa and the average pairwise percent agreement were estimated with ReCal2. Cohen's kappa was .68, and the agreement reached was 90.8%, both considered satisfactory. To test the hypothesis relations among SA and students' emotional engagement, a structural equation model (SEM) was estimated. Results demonstrated a good fit of the data: RMSEA = .04, SRMR = .03, TLI = .99, CFI = .99. Specifically, the results showed that student’s sentiment regarding their teachers’ teaching positively predicted their emotional engagement (β == .16 [.02, -.30]). In other words, when students' opinion toward their instructors' teaching practices is positive, it is more likely for students to engage emotionally in the subject. Altogether, the results show a promising future for sentiment analysis techniques in the field of education. They suggest the usefulness of this tool when evaluating relations among teaching practices and student outcomes.Keywords: sentiment analysis, students' evaluation of teaching, structural-equation modelling, emotional engagement
Procedia PDF Downloads 854136 Automatic Queuing Model Applications
Authors: Fahad Suleiman
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Queuing, in medical system is the process of moving patients in a specific sequence to a specific service according to the patients’ nature of illness. The term scheduling stands for the process of computing a schedule. This may be done by a queuing based scheduler. This paper focuses on the medical consultancy system, the different queuing algorithms that are used in healthcare system to serve the patients, and the average waiting time. The aim of this paper is to build automatic queuing system for organizing the medical queuing system that can analyses the queue status and take decision which patient to serve. The new queuing architecture model can switch between different scheduling algorithms according to the testing results and the factor of the average waiting time. The main innovation of this work concerns the modeling of the average waiting time is taken into processing, in addition with the process of switching to the scheduling algorithm that gives the best average waiting time.Keywords: queuing systems, queuing system models, scheduling algorithms, patients
Procedia PDF Downloads 3544135 Strength Translation from Spun Yarns to Woven Fabrics
Authors: Anindya Ghosh
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Structural parameters, yarn to yarn friction, strength of ring, rotor, air-jet and open-end friction spun yarns and the strength of fabrics made from these yarns are measured. The ratio of fabric strip strength per yarn and corresponding single yarn strength is considered as a measure of quantifying the fabric assistance. Mechanism of yarn failure inside the fabric is different as that of single yarn and the former exhibit more fibre rupture. Fabrics made from weaker yarns have higher ratio of strip strength to single yarn strength than that made from stronger yarns due to larger increase in the percentage of rupture fibres in the former. The fabric assistance also depends to some extent on the degree of gripping of the yarns that is influenced by the yarn to yarn friction, extent of yarn flattening and yarn diameter.Keywords: fabric assistance, fabric strength, yarn diameter, yarn friction, yarn strength
Procedia PDF Downloads 2494134 [Keynote Talk]: Formal Specification and Description Language and Message Sequence Chart to Model and Validate Session Initiation Protocol Services
Authors: Sa’ed Abed, Mohammad H. Al Shayeji, Ovais Ahmed, Sahel Alouneh
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Session Initiation Protocol (SIP) is a signaling layer protocol for building, adjusting and ending sessions among participants including Internet conferences, telephone calls and multimedia distribution. SIP facilitates user movement by proxying and forwarding requests to the present location of the user. In this paper, we provide a formal Specification and Description Language (SDL) and Message Sequence Chart (MSC) to model and define the Internet Engineering Task Force (IETF) SIP protocol and its sample services resulted from informal SIP specification. We create an “Abstract User Interface” using case analysis so that can be applied to identify SIP services more explicitly. The issued sample SIP features are then used as case scenarios; they are revised in MSCs format and validated to their corresponding SDL models.Keywords: modeling, MSC, SDL, SIP, validating
Procedia PDF Downloads 2104133 Adsorption Studies of Methane on Zeolite NaX, LiX, KX at High Pressures
Authors: El Hadi Zouaoui, Djamel Nibou, Mohamed Haddouche, Wan Azlina Wan Ab Karim Ghani, Samira Amokrane
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In this study, CH₄ adsorption isotherms on NaX or Faujasite X and exchanged zeolites with Li⁺(LiX), and K⁺(KX) at different temperatures (298, 308, 323 and 353 K) has been investigated, using high pressure (3 MPa (30 bar)) thermo-gravimetric analyser. The experimental results were then validated using several isothermal kinetics models, namely Langmuir, Toth, and Marczewski-Jaroniec, followed by a calculation of the error coefficients between the experimental and theoretical results. It was found that the CH₄ adsorption isotherms are characterized by a strong increase in adsorption at low pressure and a tendency towards a high pressure limit value Qₘₐₓ. The size and position of the exchanged cations, the spherical shape of methane, the specific surface, and the volume of the pores revealed the most important influence parameters for this study. These results revealed that the experimentation and the modeling, well correlated with Marczewski-Jaroniec, Toth, and gave the best results whatever the temperature and the material used.Keywords: CH₄ adsorption, exchange cations, exchanged zeolite, isotherm study, NaX zeolite
Procedia PDF Downloads 2494132 Vibroacoustic Modulation with Chirp Signal
Authors: Dong Liu
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By sending a high-frequency probe wave and a low-frequency pump wave to a specimen, the vibroacoustic method evaluates the defect’s severity according to the modulation index of the received signal. Many studies experimentally proved the significant sensitivity of the modulation index to the tiny contact type defect. However, it has also been found that the modulation index was highly affected by the frequency of probe or pump waves. Therefore, the chirp signal has been introduced to the VAM method since it can assess multiple frequencies in a relatively short time duration, so the robustness of the VAM method could be enhanced. Consequently, the signal processing method needs to be modified accordingly. Various studies utilized different algorithms or combinations of algorithms for processing the VAM signal method by chirp excitation. These signal process methods were compared and used for processing a VAM signal acquired from the steel samples.Keywords: vibroacoustic modulation, nonlinear acoustic modulation, nonlinear acoustic NDT&E, signal processing, structural health monitoring
Procedia PDF Downloads 994131 Women Empowerment and Sustainable Community Development: Understanding the Challenges for Responsive Action
Authors: Albert T. Akume, Ankama G. Rosecana, Micheal Solomon
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Every citizen has rights that must be respected by others in the community. Ironically however, women in most communities are not accorded some of those rights as the male folks. This has not only facilitated their disempowerment but inhibited them from being treated with equal dignity that they deserve as their male counterpart; despite their valuable contribution to the society. Those forces against women empowerment are not limited to socio-cultural practices alone, but the character and nature of the state in Nigeria point to indicators of systemic and structural exclusion embedded in its framework. The consequence of this is that the vital contributions of women to sustainable community development have eluded many communities in Nigeria with adverse tell-tell signs on the environment. It is for this reason that the objective of this study is not only to highlight the causes and challenges associated with women disempowerment, but also to draw attention to the need to correct those anomaly against women in order to genuinely empower them to contribute to sustainable community development in Nigeria.Keywords: capacity development, community, social sustainability, sustainable development, women empowerment
Procedia PDF Downloads 4224130 Sloshing-Induced Overflow Assessment of the Seismically-Isolated Nuclear Tanks
Authors: Kihyon Kwon, Hyun T. Park, Gil Y. Chung, Sang-Hoon Lee
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This paper focuses on assessing sloshing-induced overflow of the seismically-isolated nuclear tanks based on Fluid-Structure Interaction (FSI) analysis. Typically, fluid motion in the seismically-isolated nuclear tank systems may be rather amplified and even overflowed under earthquake. Sloshing-induced overflow in those structures has to be reliably assessed and predicted since it can often cause critical damages to humans and environments. FSI analysis is herein performed to compute the total cumulative overflowed water volume more accurately, by coupling ANSYS with CFX for structural and fluid analyses, respectively. The approach is illustrated on a nuclear liquid storage tank, Spent Fuel Pool (SFP), forgiven conditions under consideration: different liquid levels, Peak Ground Accelerations (PGAs), and post earthquakes.Keywords: FSI analysis, seismically-isolated nuclear tank system, sloshing-induced overflow
Procedia PDF Downloads 4744129 Flexible Design of Triboelectric Nanogenerators for Efficient Vibration Energy Harvesting
Authors: Meriam Khelifa
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In recent years, many studies have focused on the harvesting of the vibrations energy to produce electrical energy using contact separation (CS) triboelectric nanogenerators (TENG). The simplest design for a TENG consists of a capacitor comprising a single moving electrode. The conversion efficiency of vibration energy into electrical energy can, in principle, reach 100%. But to actually achieve this objective, it is necessary to optimize the parameters of the TENG, such as the dielectric constant and the thickness of the insulator, the load resistance, etc. In particular, the use of a switch which is actioned at optimal times within the TENG cycle is essential. Using numerical modeling and experimental design, we applied a methodology to find the TENG parameters which optimize the energy transfer efficiency (ETE) to almost 100% for any vibration frequency and amplitude. The rather simple design of a TENG is promising as an environment friendly device. It opens the doors for harvesting acoustic vibrations from the environment and to design effective protection against environmental noise.Keywords: vibrations, CS TENG, efficiency, design of experiments
Procedia PDF Downloads 904128 Improving Sales through Inventory Reduction: A Retail Chain Case Study
Authors: M. G. Mattos, J. E. Pécora Jr, T. A. Briso
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Today's challenging business environment, with unpredictable demand and volatility, requires a supply chain strategy that handles uncertainty and risks in the right way. Even though inventory models have been previously explored, this paper seeks to apply these concepts on a practical situation. This study involves the inventory replenishment problem, applying techniques that are mainly based on mathematical assumptions and modeling. The primary goal is to improve the retailer’s supply chain processes taking store differences when setting the various target stock levels. Through inventory review policy, picking piece implementation and minimum exposure definition, we were able not only to promote the inventory reduction as well as improve sales results. The inventory management theory from literature review was then tested on a single case study regarding a particular department in one of the largest Latam retail chains.Keywords: inventory, distribution, retail, risk, safety stock, sales, uncertainty
Procedia PDF Downloads 2684127 Effect of Inhibitor of the Angiotensin Converting Enzyme in the Mediterranean Flour Moth: Structural Parametrs of Cuticule and Ecdysteroid Amounts
Authors: S. Yezli-Touiker, L. Kirane-Amrani, N. Soltani-Mazouni
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Ephestia kuehniella Zeller Lepidoptera, Pyralidae commonly called Mediterranean flour moth, is serious cosmopolitan pest of stored grain products, particularly flour Month. This species is also a source of allergen that causes asthma and rhinitis. Captopril is an inhibitor of angiotensin converting enzyme (ACE) it was tested in vivo by topical application on development of E. kuehniella. The compound is diluted in acetone and applied topically to newly emerged pupae (10mg/2ml). Report chitin protein of cuticule and ecdysteroid Amounts were determined in vivo. Results show that the captopril does not affect chitin protein of cuticule but traitment with captopril increase the hormonal production, the quantitative analysis reveals the presence of two peaks one at third and another at fifth day.Keywords: Ephestia kuehniella, cuticule, hormone, captopril
Procedia PDF Downloads 3564126 Effect of Elastic Modulus Varieties on Helical Pile Behavior in Sand
Authors: Javad Shamsi Soosahab, Reza Ziaie Moayed
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The compressive and tensile bearing capacity of helical piles in sand is investigated by means of numerical modeling. The analyses are carried out using two-dimensional finite-element software, Optum G2. The load–displacement behavior under compression and tension is compared in different relative densities for constant and various elastic modulus. The criterion used to find the ultimate axial load is the load corresponding to 5% of the helical diameter. The results show that relative density of sand plays an essential role in the response of ultimate capacities towards various condition. Increase in elastic modulus with depth is found to play a relatively more significant role to the increase in ultimate compressive load capacities, however tension bearing capacity decreases.Keywords: helical piles, Optum G2, relative density, constant and various elastic modulus
Procedia PDF Downloads 1514125 Marketing–Operations Alignment: A Systematic Literature and Citation Network Analysis Review
Authors: Kedwadee Sombultawee, Sakun Boon-Itt
Abstract:
This research demonstrates a systematic literature review of 62 peer-reviewed articles published in academic journals from 2000-2016 focusing on the operation and marketing interface area. The findings show the three major clusters of recent research domains, which is a review of the alignment between operations and marketing, identification of variables that impact the company and analysis of the effect of interface. Moreover, the Main Path Analysis (MPA) is mapped to show the knowledge structure of the operation and marketing interface issue. Most of the empirical research focused on company performance and new product development then analyzed the data by the structural equation model or regression. Whereas, some scholars studied the conflict of these two functions and proposed the requirement or step for alignment. Finally, the gaps in the literature are provided for future research directions.Keywords: operations management, marketing, interface, systematic literature review
Procedia PDF Downloads 275