Search results for: paper sheets
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 24787

Search results for: paper sheets

6847 Doping Density Effects on Minority Carrier Lifetime in Bulk GaAs by Means of Photothermal Deflection Technique

Authors: Soufiene Ilahi

Abstract:

Photothermal effect occurs when absorbed light energy that generate a thermal wave that propagate into the sample and surrounding media. Subsequently, the propagation of the vibration of phonons or electrons causes heat transfer. In fact, heat energy is provided by non-radiative recombination process that occurs in semiconductors sample. Three heats sources are identified: surface recombination, bulk recombination and carrier thermalisation. In the last few years, Photothermal Deflection Technique PTD is a nondestructive and accurate technique that prove t ability for electronics properties investigation. In this paper, we have studied the influence of doping on minority carrier lifetime, i.e, nonradiative lifetime, surface and diffusion coefficient. In fact, we have measured the photothermal signal of two sample of GaAs doped with C et Cr.In other hand , we have developed a theoretical model that takes into account of thermal and electronics diffusion equations .In order to extract electronics parameters of GaAs samples, we have fitted the theoretical signal of PTD to the experimental ones. As a results, we have found that nonradiative lifetime is around of 4,3 x 10-8 (±11,24%) and 5 x 10-8 (±14,32%) respectively for GaAs : Si doped and Cr doped. Accordingly, the diffusion coefficient is equal 4,6 *10-4 (± 3,2%) and 5* 10-4 (± 0,14%) foe the Cr, C and Si doped GaAs respectively.

Keywords: nonradiative lifetime, mobility of minority carrier, diffusion length, surface and interface recombination in GaAs

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6846 Terrorism and National Development: A Critique of Its Aftermath on Educational Attainment

Authors: David Chapola Nggada

Abstract:

Although the concept of terrorism is not a new phenomenon to Nigeria, the protracted terrorist activities experiencing in the north-eastern part of the country since 2009, had left an indelible mark on virtually every aspects of lives whether directly or indirectly, particularly the educational sector. Indeed, since the abduction of over 200 schoolgirls at Chibok in 2014 by the insurgence, education had witnessed a setback as most school remains closed for sometimes. The aftermath of this development on education and its future multiplier effect on national development is a source of concern. Consequently, this paper is designed to examine the consequences of terrorism on educational attainment and national development among the Chibok community of Borno State. The technique employed involves a mixture of both qualitative and quantitative research work on a sample size of 79 secondary school students currently displaced from Chibok, Damboa and Askira-Uba, now residing as internally displaced persons(IDPs) in Biu, Gombe, Maiduguri. A random sample technique is used. Structured and semi-unstructured questionnaire were administered. The result shows that, a significant number of students over these years, lacked access to education and this posed a great danger to national development. Recommendations towards reinvigorating education as a panacea to social, economic cum political vices were articulated. Concerted effort should be made to create confidence in the community.

Keywords: education, effect, terrorism, national, development

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6845 Thermodynamic Performance Tests for 3D Printed Steel Slag Powder Concrete Walls

Authors: Li Guoyou, Zhang Tao, Ji Wenzhan, Huo Liang, Lin Xiqiang, Zhang Nan

Abstract:

The three dimensional (3D) printing technology has undergone rapid development in the last few years and it is possible to print engineering structures. 3D printing buildings use wastes from constructions, industries and mine tailings as “ink”, and mix it with property improved materials, such as cement, fiber etc. This paper presents a study of the Thermodynamic performance of 3D printed walls using cement and steel slag powder. Analyses the thermal simulation regarding 3D printed walls and solid brick wall by the way of the hot-box methods and the infrared technology, and the results were contrasted with theoretical calculation. The results show that the excellent thermodynamic performance of 3D printed concrete wall made it suitable as the partial materials for self-thermal insulation walls in residential buildings. The thermodynamic performance of 3D printed concrete walls depended on the density of materials, distribution of holes, and the filling materials. Decreasing the density of materials, increasing the number of holes or replacing the filling materials with foamed concrete could improve its thermodynamic performance significantly. The average of heat transfer coefficient and thermal inertia index of 3D printed steel slag powder concrete wall all better than the traditional solid brick wall with a thickness of 240mm.

Keywords: concrete, 3D printed walls, thermodynamic performance, steel slag powder

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6844 How Teachers Comprehend and Support Children's Needs to Be Scientists

Authors: Anita Yus

Abstract:

Several Elementary Schools (SD) ‘favored’ by parents, especially those live in big cities in Indonesia, implicitly demand each child enrolled in the first grade of SD to be able to read, write and calculate. This condition urges the parents to push the teachers in PAUD (Kindergarten) to train their children to read, write, and calculate so they have a set of knowledge. According to Piaget, each child is capable of acquiring knowledge when he is given the opportunity to interact with his environment (things, people, and atmosphere). Teachers can make the interaction occur. There are several learning approaches suitable for the characteristics and needs of child’s growth. This paper talks about a research result conducted to investigate how twelve teachers of early childhood program comprehend the constructivist theory of Piaget, and how they inquire, how the children acquire and construct a number of knowledge through occurred interactions. This is a qualitative research with an observation method followed up by a focus group discussion (FGD). The research result shows that there is a reciprocal interaction between the behaviors of teachers and children affected by the size of the classroom and learning source, teaching experiences, education background, teachers’ attitude and motivation, as well as the way the teachers interpret and support the children’s needs. The teachers involved in this research came up with varied perspective on how knowledge acquired by children at first and how they construct it. This research brings a new perspective in understanding children as scientists.

Keywords: constructivist approach, young children as a scientist, teacher practice, teacher education

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6843 Intelligent Building as a Pragmatic Approach towards Achieving a Sustainable Environment

Authors: Zahra Hamedani

Abstract:

Many wonderful technological developments in recent years has opened up the possibility of using intelligent buildings for a number of important applications, ranging from minimizing resource usage as well as increasing building efficiency to maximizing comfort, adaption to inhabitants and responsiveness to environmental changes. The concept of an intelligent building refers to the highly embedded, interactive environment within which by exploiting the use of artificial intelligence provides the ability to know its configuration, anticipate the optimum dynamic response to prevailing environmental stimuli, and actuate the appropriate physical reaction to provide comfort and efficiency. This paper contains a general identification of the intelligence paradigm and its impacts on the architecture arena, that with examining the performance of artificial intelligence, a mechanism to analyze and finally for decision-making to control the environment will be described. This mechanism would be a hierarchy of the rational agents which includes decision-making, information, communication and physical layers. This multi-agent system relies upon machine learning techniques for automated discovery, prediction and decision-making. Then, the application of this mechanism regarding adaptation and responsiveness of intelligent building will be provided in two scales of environmental and user. Finally, we review the identifications of sustainability and evaluate the potentials of intelligent building systems in the creation of sustainable architecture and environment.

Keywords: artificial intelligence, intelligent building, responsiveness, adaption, sustainability

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6842 Development of High Quality Refractory Bricks from Fireclays for Industrial Applications

Authors: David E. Esezobor, Friday I. Apeh, Harrison O. Onovo, Ademola A. Agbeleye

Abstract:

Available indigenous refractory bricks in Nigeria can only be used in the lining of furnaces for melting of cast iron operating at less than 1,400°C or in preheating furnaces due to their low refractoriness less than 1,500°C. The bricks crack and shatter on heating at 1350 to 1450°C. In this paper, a simple and adaptable technology of manufacturing high-quality refractory bricks from selected Nigerian clays for furnace linings was developed. Fireclays from Onibode, Owode-Ketu in Ogun State and Kwoi in Kaduna State were crushed, ground, and sieved into various grain sizes using standard techniques. The pulverized clays were blended with alumina in various mix ratios and indurated in the furnace at 900 – 16000C. Their chemical, microstructure and mineralogical properties were characterized using atomic absorption spectrophotometry, scanning electron microscopy and x-ray diffraction spectrometry respectively. The mineralogical and spectrochemical analyses suggested that the clays are of siliceous alumino-silicate and acidic in nature. The appropriate blending of fireclays with alumina provided the tremendous improvement in the refractoriness of the bricks and other acceptable service properties comparable with imported refractory bricks. The change in microstructure from pseudo-hexagonal grains to equiaxed grains of well – ordered sequence of structural layers could be responsible for the improved properties.

Keywords: alumina, furnace, industry, manufacturing, refractoriness

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6841 Numerical Analysis of Shear Crack Propagation in a Concrete Beam without Transverse Reinforcement

Authors: G. A. Rombach, A. Faron

Abstract:

Crack formation and growth in reinforced concrete members are, in many cases, the cause of the collapse of technical structures. Such serious failures impair structural behavior and can also damage property and persons. An intensive investigation of the crack propagation is indispensable. Numerical methods are being developed to analyze crack growth in an element and to detect fracture failure at an early stage. For reinforced concrete components, however, further research and action are required in the analysis of shear cracks. This paper presents numerical simulations and continuum mechanical modeling of bending shear crack propagation in a three-dimensional reinforced concrete beam without transverse reinforcement. The analysis will provide a further understanding of crack growth and redistribution of inner forces in concrete members. As a numerical method to map discrete cracks, the extended finite element method (XFEM) is applied. The crack propagation is compared with the smeared crack approach using concrete damage plasticity. For validation, the crack patterns of real experiments are compared with the results of the different finite element models. The evaluation is based on single span beams under bending. With the analysis, it is possible to predict the fracture behavior of concrete members.

Keywords: concrete damage plasticity, crack propagation, extended finite element method, fracture mechanics

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6840 Resistance and Sub-Resistances of RC Beams Subjected to Multiple Failure Modes

Authors: F. Sangiorgio, J. Silfwerbrand, G. Mancini

Abstract:

Geometric and mechanical properties all influence the resistance of RC structures and may, in certain combination of property values, increase the risk of a brittle failure of the whole system. This paper presents a statistical and probabilistic investigation on the resistance of RC beams designed according to Eurocodes 2 and 8, and subjected to multiple failure modes, under both the natural variation of material properties and the uncertainty associated with cross-section and transverse reinforcement geometry. A full probabilistic model based on JCSS Probabilistic Model Code is derived. Different beams are studied through material nonlinear analysis via Monte Carlo simulations. The resistance model is consistent with Eurocode 2. Both a multivariate statistical evaluation and the data clustering analysis of outcomes are then performed. Results show that the ultimate load behaviour of RC beams subjected to flexural and shear failure modes seems to be mainly influenced by the combination of the mechanical properties of both longitudinal reinforcement and stirrups, and the tensile strength of concrete, of which the latter appears to affect the overall response of the system in a nonlinear way. The model uncertainty of the resistance model used in the analysis plays undoubtedly an important role in interpreting results.

Keywords: modelling, Monte Carlo simulations, probabilistic models, data clustering, reinforced concrete members, structural design

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6839 Needs Analysis Survey of Hearing Impaired Students’ Teachers in Elementary Schools for Designing Curriculum Plans and Improving Human Resources

Authors: F. Rashno Seydari, M. Nikafrooz

Abstract:

This paper intends to study needs analysis of hearing-impaired students’ teachers in elementary schools all over Iran. The subjects of this study were 275 teachers who were teaching hearing-impaired students in elementary schools. The participants were selected by a quota sampling method. To collect the data, questionnaires of training needs consisting of 41 knowledge items and 31 performance items were used. The collected data were analyzed by using SPSS software in the form of descriptive analyses (frequency and mean) and inferential analyses (one sample t-test, paired t-test, independent t-test, and Pearson correlation coefficient). The findings of the study indicated that teachers generally have considerable needs in knowledge and performance domains. In 32 items out of the total 41 knowledge domain items and in the 27 items out of the total 31 performance domain items, the teachers had considerable needs. From the quantitative point of view, the needs of the performance domain were more than those of the knowledge domain, so they have to be considered as the first priority in training these teachers. There was no difference between the level of the needs of male and female teachers. There was a significant difference between the knowledge and performance domain needs and the teachers’ teaching experience, 0.354 and 0.322 respectively. The teachers who had been trained in working with hearing-impaired students expressed more training needs (both knowledge and performance).

Keywords: educational needs analysis, teachers of hearing impaired students, knowledge domain, function domain

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6838 Uplifting Citizens Participation: A Gov 2.0 Framework

Authors: Mohammed Aladalah

Abstract:

The emergence of digital citizens is no longer mere speculation; therefore, governments’ use of Web 2.0 tools (hereafter Gov 2.0) should be a part of all current and future e-government plans. The potential of Gov 2.0 to facilitate greater communication, participation, and collaboration with citizens has been highlighted and discussed extensively in recent literature. However, the current levels of citizens’ participation in Gov 2.0 have not lived up to the hype. Therefore, governments need to rethink the way in which they implement Gov 2.0, and take advantage of the digitally-engaged population. We propose a two-dimensional framework to tackle this issue: first, on the supply side, governments tend to use Gov 2.0 mainly for the dissemination of information and for self-promotion without the desire to encourage any interaction with citizens; this is due to many reasons, including the lack of time and the possibility of loss of control. The second dimension of the framework is the demand side; citizens are unwilling to participate in Gov 2.0 activities because they do not perceive its value or trust the government. We attempt to consider the elements of both supply and demand in order to provide a comprehensive solution whereby the potential of Gov 2.0 can be fully utilized. Our framework is based on the theoretical foundation of service science and value co-creation theory. This paper makes two significant contributions: (a) it provides an initial framework intended to increase citizens’ participation in Gov 2.0; and (b) it enhances the understanding of the government’s Gov 2.0 applications, particularly in terms of factors that ensure their attractiveness for citizens. This work is the first step in a comprehensive research undertaking, the purpose of which is to study public’s engagement with the Gov 2.0 concept. It contributes to providing a better understanding of e-government and its future.

Keywords: e-government, Gov 2.0, citizens participation, digital citizen

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6837 Crowdfunding in Funding Lithuanian Movies

Authors: Irena Alperyte

Abstract:

Since the regaining of the Independence, the Lithuanian state has been confronting an increasingly dramatic challenge because of the lack of funding sources dedicated to the film industries. During the Soviet times, Lithuanian film was under a total supervision of the Soviet functioners. This means that the responsibility of the state to make movies was of a monopolist character. The filmmakers’ community of the newly independent state needed to learn how to develop their fundraising skills, co-production and marketing techniques. Currently, Lithuanian film is experiencing a new phase concerning its funding: it is exploring the possibilities of motivating the public to invest in entertainment via crowd funding and crowd sourcing techniques and making these activities an alternative way of funding films. The paper aims at the exploration of the existing film financing practices in Lithuania and abroad and provides recommendations on how to improve the alternative Lithuanian film financing strategy via employing new possibilities, such as crowd funding and other alternative marketing tools. Objectives: 1) To examine the theories on creative industries and possibilities for their application. 2) To analyze the current situation in the film industry Lithuania. 3) To analyze the statistical data on movie theater visitors in Lithuania. 4) To discuss alternative options for film financing system. 5) To look through the alternative funding strategies tailored for Lithuanian film industry. 6) To propose recommendations for alternative funding strategies in Lithuanian film fundraising.

Keywords: creative industries, film, funding, fun theory

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6836 Three Dimensional Model of Full Scale Plate Load Test on Stone Column in Sabkha Deposit: Case Study from Jubail Industrial City - Saudi Arabia

Authors: Hassan. A. Abas, Saad A. Aiban

Abstract:

Soil improvement by means of stone column method is used to improve sabkha soils in order to limit total and differential settlement and to achieve the required bearing capacity. Full-scale plate test was performed on site to confirm the achievement of required bearing capacity at the specified settlement. Despite the fact that this technique is widely used to improve sabkha soils, there are no studies focusing on the behavior of stone columns in such problematic soils. Sabkha soils are known for its high compressibility, low strength and water sensitivity due to loss of salt cementation upon flooding during installation of stone columns. Numerical modeling of plate load test assist to understand complicated behavior of sabkha – stone column interaction. This paper presents a three-dimensional Finite element model, using PLAXIS 3D software, to simulate vertical plate load tests on a stone column installed in sabkha. The predicted settlement values are in reasonable agreement with the field measure values and the field load - settlement curve can be predicted with good accuracy.

Keywords: soil improvement, stone column, sabkha, PLAXIS 3D

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6835 Acoustic Blood Plasmapheresis in Polymeric Resonators

Authors: Itziar Gonzalez, Pilar Carreras, Alberto Pinto, Roque Ruben Andres

Abstract:

Acoustophoretic separation of plasma from blood is based on a collection process of the blood cells, driven by an acoustic radiation force. The number of cells, their concentration, and the sample hydrodynamics are involved in these processes. However, their influence on the acoustic blood response has not yet been reported in the literature. Addressing it, this paper presents an experimental study of blood samples exposed to ultrasonic standing waves at different hematocrit levels and hydrodynamic conditions. The experiments were performed in a glass capillary (700µm-square cross section) actuated by a piezoelectric ceramic at 1MHz, hosting 2D orthogonal half-wavelength resonances transverse to the channel length, with a single-pressure-node along its central axis where cells collected driven by the acoustic radiation force. Four blood dilutions in PBS of 1:20, 1:10, 1:5, and 1:2 were tested at eight flow rate conditions Q=0:120µL/min. The 1:5 dilution (H=9%) demonstrated to be optimal for the plasmapheresis at any of the flow rates analyzed, requiring the shortest times to achieve plasma free of cells. The study opens new possibilities to optimize processes of plasmapheresis processes by ultrasounds at different hematocrit conditions in future personalized diagnoses/treatments involving blood samples.

Keywords: ultrasounds, microfluidics, flow rate, acoustophoresis, polymeric resonators

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6834 Multi Object Tracking for Predictive Collision Avoidance

Authors: Bruk Gebregziabher

Abstract:

The safe and efficient operation of Autonomous Mobile Robots (AMRs) in complex environments, such as manufacturing, logistics, and agriculture, necessitates accurate multiobject tracking and predictive collision avoidance. This paper presents algorithms and techniques for addressing these challenges using Lidar sensor data, emphasizing ensemble Kalman filter. The developed predictive collision avoidance algorithm employs the data provided by lidar sensors to track multiple objects and predict their velocities and future positions, enabling the AMR to navigate safely and effectively. A modification to the dynamic windowing approach is introduced to enhance the performance of the collision avoidance system. The overall system architecture encompasses object detection, multi-object tracking, and predictive collision avoidance control. The experimental results, obtained from both simulation and real-world data, demonstrate the effectiveness of the proposed methods in various scenarios, which lays the foundation for future research on global planners, other controllers, and the integration of additional sensors. This thesis contributes to the ongoing development of safe and efficient autonomous systems in complex and dynamic environments.

Keywords: autonomous mobile robots, multi-object tracking, predictive collision avoidance, ensemble Kalman filter, lidar sensors

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6833 Effect of Nanofibers on the Behavior of Cement Mortar and Concrete

Authors: Mostafa Osman, Ata El-Kareim Shoeib

Abstract:

The main objective of this paper is study the influence of carbon nano-tubes fibers and nano silica fibers on the characteristic compressive strength and flexural strength on concrete and cement mortar. Twelve tested specimens were tested with square section its dimensions (40*40*160) mm, divided into four groups. The first and second group studied the effect of carbon nano-tubes (CNTs) fiber with different percentage equal to 0.0, 0.11 %, 0.22 %, and 0.33 % by weight of cement and effect of nano-silica (nS) fibers with different percentages equal to 0.0, 1.0 %, 2.0 %, and 3.0 % by weight of cement on the cement mortar. The third and fourth groups studied the effect of CNTs fiber with different percentage equal to 0.0 %, 0.11 %, and 0.22 % by weight of cement, and effect of nS fibers with different percentages were equal to 0.0 %, 1.0%, and 2.0 % by weight of cement on the concrete. The compressive strength and flexural strength at 7, 28, and 90 days is determined. From analysis of tested results concluded that the nano-fiber is more effective when used with cement mortar than that of used with concrete because of increasing the surface area, decreasing the pore and the collection of nano-fiber. And also by adding nano-fiber the improvement of flexural strength of concrete and cement mortar is more than improvement of compressive strength.

Keywords: carbon nano-tubes (CNTs) fibres, nano-silica (nS) fibres, compressive strength, flexural strength

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6832 The Prototype of the Solar Energy Utilization for the Finding Sustainable Conditions in the Future: The Solar Community with 4000 Dwellers 960 Families, equal to 480 Solar Dwelling Houses and 32 Mansion Buildings (480 Dwellers)

Authors: Kunihisa Kakumoto

Abstract:

This technical paper is for the prototype of solar energy utilization for finding sustainable conditions. This model has been simulated under the climate conditions in Japan. At the beginning of the study, the solar model house was built up on site. And the concerned data was collected in this model house for several years. On the basis of these collected data, the concept on the solar community was built up. For the finding sustainable conditions, the amount of the solar energy generation and its reduction of carbon dioxide and the reduction of carbon dioxide by the green planting and the amount of carbon dioxide according to the normal daily life in the solar community and the amount of the necessary water for the daily life in the solar community and the amount of the water supply by the rainfall on-site were calculated. These all values were taken into consideration. The relations between each calculated result are shown in the expression of inequality. This solar community and its consideration for finding sustainable conditions can be one prototype to do the feasibility study for our life in the future

Keywords: carbon dioxide, green planting, smart city, solar community, sustainable condition, water activity

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6831 Acoustic and Thermal Isolation Performance Comparison between Recycled and Ceramic Roof Tiles Using Digital Holographic Interferometry

Authors: A. Araceli Sánchez, I. Manuel H. De la Torre, S. Fernando Mendoza, R. Cesar Tavera, R. Manuel de J. Briones

Abstract:

Recycling, as part of any sustainable environment, is continuously evolving and impacting on new materials in manufacturing. One example of this is the recycled solid waste of Tetra Pak ™ packaging, which is a highly pollutant waste as it is not biodegradable since it is manufactured with different materials. The Tetra Pak ™ container consists of thermally joined layers of paper, aluminum and polyethylene. Once disposed, this packaging is recycled by completely separating the paperboard from the rest of the materials. The aluminum and the polyethylene remain together and are used to create the poly-aluminum, which is widely used to manufacture roof tiles. These recycled tiles have different thermal and acoustic properties compared with traditional manufactured ceramic and cement tiles. In this work, we compare a group of tiles using nondestructive optical testing to measure the superficial micro deformations of the tiles under well controlled experiments. The results of the acoustic and thermal tests show remarkable differences between the recycled tile and the traditional ones. These results help to determine which tile could be better suited to the specific environmental conditions in countries where extreme climates, ranging from tropical, desert-like, to very cold are experienced throughout the year.

Keywords: acoustic, digital holographic interferometry, isolation, recycled, roof tiles, sustainable, thermal

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6830 Modeling of Microelectromechanical Systems Diaphragm Based Acoustic Sensor

Authors: Vasudha Hegde, Narendra Chaulagain, H. M. Ravikumar, Sonu Mishra, Siva Yellampalli

Abstract:

Acoustic sensors are extensively used in recent days not only for sensing and condition monitoring applications but also for small scale energy harvesting applications to power wireless sensor networks (WSN) due to their inherent advantages. The natural frequency of the structure plays a major role in energy harvesting applications since the sensor key element has to operate at resonant frequency. In this paper, circular diaphragm based MEMS acoustic sensor is modelled by Lumped Element Model (LEM) and the natural frequency is compared with the simulated model using Finite Element Method (FEM) tool COMSOL Multiphysics. The sensor has the circular diaphragm of 3000 µm radius and thickness of 30 µm to withstand the high SPL (Sound Pressure Level) and also to withstand the various fabrication steps. A Piezoelectric ZnO layer of thickness of 1 µm sandwiched between two aluminium electrodes of thickness 0.5 µm and is coated on the diaphragm. Further, a channel with radius 3000 µm radius and length 270 µm is connected at the bottom of the diaphragm. The natural frequency of the structure by LEM method is approximately 16.6 kHz which is closely matching with that of simulated structure with suitable approximations.

Keywords: acoustic sensor, diaphragm based, lumped element modeling (LEM), natural frequency, piezoelectric

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6829 Solution of Singularly Perturbed Differential Difference Equations Using Liouville Green Transformation

Authors: Y. N. Reddy

Abstract:

The class of differential-difference equations which have characteristics of both classes, i.e., delay/advance and singularly perturbed behaviour is known as singularly perturbed differential-difference equations. The expression ‘positive shift’ and ‘negative shift’ are also used for ‘advance’ and ‘delay’ respectively. In general, an ordinary differential equation in which the highest order derivative is multiplied by a small positive parameter and containing at least one delay/advance is known as singularly perturbed differential-difference equation. Singularly perturbed differential-difference equations arise in the modelling of various practical phenomena in bioscience, engineering, control theory, specifically in variational problems, in describing the human pupil-light reflex, in a variety of models for physiological processes or diseases and first exit time problems in the modelling of the determination of expected time for the generation of action potential in nerve cells by random synaptic inputs in dendrites. In this paper, we envisage the use of Liouville Green Transformation to find the solution of singularly perturbed differential difference equations. First, using Taylor series, the given singularly perturbed differential difference equation is approximated by an asymptotically equivalent singularly perturbation problem. Then the Liouville Green Transformation is applied to get the solution. Several model examples are solved, and the results are compared with other methods. It is observed that the present method gives better approximate solutions.

Keywords: difference equations, differential equations, singular perturbations, boundary layer

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6828 Menopause Cultural Research: A Comparative Study of National and Diasporic Chinese Menopausal Women’s Perceptions and Lived Experience of Menopause

Authors: Yilin Wang, Ayumi Goto

Abstract:

Although most females will experience menopause due to social value habits of cultural factors, some Chinese women may lack the confidence to talk about the problems they are experiencing while going through menopause. Also, sometimes the inappropriateness of medical terminology leads to panic when women face the symptoms associated with menopause. On top of that, when women avoid discussing menopause as a topic, others are less likely to pay attention to the needs of menopausal women as their bodies change. This research will compare the experience of Chinese menopausal women and diasporic Chinese women's perceptions of menopause. A qualitative study will be conducted by collecting and analyzing experiences and perceptions to compare differences in women's perceptions of menopause, considering cultural and social factors. In addition, the study will gather information on the differences in the conceptualization of menopause between the Chinese and Canadian medical fields. Co-design sessions will be held to establish how to bring menopause to the attention of people other than women. Furthermore, a support network for menopause women will be created through these co-design sessions. It is hoped that this research will contribute to a proper understanding of menopause and provide support for Chinese women. This research is built upon feminist standpoint theory and inclusive design theory. The results of this study will be presented in this paper.

Keywords: menopause, feminist standpoint theory, Chinese national & diasporic women, inclusive design

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6827 Numerical Pricing of Financial Options under Irrational Exercise Times and Regime-Switching Models

Authors: Mohammad Saber Rohi, Saghar Heidari

Abstract:

In this paper, we studied the pricing problem of American options under a regime-switching model with the possibility of a non-optimal exercise policy (early or late exercise time) which is called an irrational strategy. For this, we consider a Markovmodulated model for the dynamic of the underlying asset as an alternative model to the classical Balck-Scholes-Merton model (BSM) and an intensity-based model for the irrational strategy, to provide more realistic results for American option prices under the irrational behavior in real financial markets. Applying a partial differential equation (PDE) approach, the pricing problem of American options under regime-switching models can be formulated as coupled PDEs. To solve the resulting systems of PDEs in this model, we apply a finite element method as the numerical solving procedure to the resulting variational inequality. Under some appropriate assumptions, we establish the stability of the method and compare its accuracy to some recent works to illustrate the suitability of the proposed model and the accuracy of the applied numerical method for the pricing problem of American options under the regime-switching model with irrational behaviors.

Keywords: irrational exercise strategy, rationality parameter, regime-switching model, American option, finite element method, variational inequality

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6826 Using Shape Memory Alloys for Structural Engineering Applications

Authors: Donatello Cardone

Abstract:

Shape memory alloys (SMAs) have great potential for use in the field of civil engineering. The author of this manuscript has been involved, since 1996, in several experimental and theoretical studies on the application of SMAs in structural engineering, within national and international research projects. This paper provides an overview of the main results achieved, including the conceptual design, implementation, and testing of different SMA-based devices, namely: (i) energy-dissipating braces for RC buildings, (ii) seismic isolation devices for buildings and bridges, (iii) smart tie-rods for arches and vaults and (iv) seismic restrainers for bridges. The main advantages of using SMA-based devices in the seismic protection of structures derive from the double-flag shape of their hysteresis loops, which implies three favourable features, i.e., self-centering capability, good energy dissipation capability, and high stiffness for small displacements. The main advantages of SMA-based units for steel tie-rods are associated with the thermal behaviour of superelastic SMAs, which is antagonistic compared to that of steel. This implies a strong reduction of force changes due to air temperature variations. Finally, SMA-based seismic restrainers proved to be effective in preventing bridge deck unseating and pounding.

Keywords: seismic protection of structures, shape memory alloys, structural engineering, steel tie-rods, seismic restrainers for bridges

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6825 Free Vibration Analysis of FG Nanocomposite Sandwich Beams Using Various Higher-Order Beam Theories

Authors: Saeed Kamarian

Abstract:

In this paper, free vibrations of Functionally Graded Sandwich (FGS) beams reinforced by randomly oriented Single-Walled Carbon Nanotubes (SWCNTs) are investigated. The Eshelby–Mori–Tanaka approach based on an equivalent fiber is used to investigate the material properties of the structure. The natural frequencies of the FGS nanocomposite beam are analyzed based on various Higher-order Shear Deformation Beam Theories (HSDBTs) and using an analytical method. The verification study represents the simplicity and accuracy of the method for free vibration analysis of nanocomposite beams. The effects of carbon nanotube volume fraction profiles in the face layers, length to span ratio and thicknesses of face layers on the natural frequency of structure are studied for the different HSDBTs. Results show that by utilizing the FGS type of structures, free vibration characteristics of structures can be improved. A comparison is also provided to show the difference between natural frequency responses of the FGS nanocomposite beam reinforced by aligned and randomly oriented SWCNT.

Keywords: sandwich beam, nanocomposite beam, functionally graded materials, higher-order beam theories, Mori-Tanaka approach

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6824 Digital Art Fabric Prints: Procedure, Process and Progress

Authors: Tripti Singh

Abstract:

Digital tools are merging boundaries of different mediums as endeavoured artists exploring new areas. Digital fabric printing has motivated artists to create prints by combining images acquired by photograph, scanned images, computer graphics and microscopic imaginary etc to name few, with traditional media such as hand drawing, weaving, hand printed patterns, printing making techniques and so on. It opened whole new world of possibilities for artists to search, research and combine old and contemporary mediums for their unique art prints. As artistic medium digital art fabrics have aesthetic values which have impact and influence on not only on a personality but also interiors of a living or work space. In this way it can be worn, as fashion statement and also an interior decoration. Digital art fabric prints gives opportunity to print almost everything on any fabric with long lasting prints quality. Single edition and limited editions are possible for maintaining scarcity and uniqueness of an art form. These fabric prints fulfill today’s need, as they are eco-friendly in nature and they produce less wastage compared to traditional fabric printing techniques. These prints can be used to make unique and customized curtains, quilts, clothes, bags, furniture, dolls, pillows, framed artwork, costumes, banners and much, much more. This paper will explore the procedure, process, and progress techniques of digital art fabric printing in depth with suitable pictorial examples.

Keywords: digital art, fabric prints, digital fabric prints, new media

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6823 Real-Time Recognition of Dynamic Hand Postures on a Neuromorphic System

Authors: Qian Liu, Steve Furber

Abstract:

To explore how the brain may recognize objects in its general,accurate and energy-efficient manner, this paper proposes the use of a neuromorphic hardware system formed from a Dynamic Video Sensor~(DVS) silicon retina in concert with the SpiNNaker real-time Spiking Neural Network~(SNN) simulator. As a first step in the exploration on this platform a recognition system for dynamic hand postures is developed, enabling the study of the methods used in the visual pathways of the brain. Inspired by the behaviours of the primary visual cortex, Convolutional Neural Networks (CNNs) are modeled using both linear perceptrons and spiking Leaky Integrate-and-Fire (LIF) neurons. In this study's largest configuration using these approaches, a network of 74,210 neurons and 15,216,512 synapses is created and operated in real-time using 290 SpiNNaker processor cores in parallel and with 93.0% accuracy. A smaller network using only 1/10th of the resources is also created, again operating in real-time, and it is able to recognize the postures with an accuracy of around 86.4% -only 6.6% lower than the much larger system. The recognition rate of the smaller network developed on this neuromorphic system is sufficient for a successful hand posture recognition system, and demonstrates a much-improved cost to performance trade-off in its approach.

Keywords: spiking neural network (SNN), convolutional neural network (CNN), posture recognition, neuromorphic system

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6822 Implementing Online Applications to Allow Marketing Personnel to Share Their Experiences

Authors: Ishak Kamal Baskhayroun

Abstract:

This study examines consumer attitudes toward mobile marketing, especially toward SMS marketing. Unlike similar studies, this study does not focus on the young, but includes consumers who are in the 18-70 age range to the field research. According to the results, it has been concluded that most participants think SMS marketing is disturbing. Most important problems with SMS marketing are about getting subscribed to message lists without the permission of the receiver; the high number of messages sent; and the irrelevancy of the message content. The emergence of sponsorship as a new marketing communication tool and a source of competitive advantage in the marketplace has changed the entire marketing communication process. Sponsorship has overtaken other marketing communication tools in terms of growth and expenditure. This paper seeks to evaluate the role of sponsorship in marketing communication tools. The study recommends that proper measures be taken before the company embarks into sponsorship programs. This is necessary because investment in sponsorship does not always guarantee sustainable competitive advantage in the marketplace.Mobile phones are one of the direct marketing tools that can be used to reach today’s hard to reach consumers. Mobile phones are very personal devices and they are always carried with the consumer, where ever they go. This creates an opportunity for marketers to create personalized marketing communications messages and send them on the right time and place.

Keywords: employee organizational performance, internal marketing, internal customer, direct marketing, mobile phones mobile marketing, sms advertising, marketing sponsorship, marketing communication theories, marketing communication tools corporate responsibility

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6821 Numerical Simulation of Fluid-Structure Interaction on Wedge Slamming Impact by Using Particle Method

Authors: Sung-Chul Hwang, Di Ren, Sang-Moon Yoon, Jong-Chun Park, Abbas Khayyer, Hitoshi Gotoh

Abstract:

The slamming impact problem has a very important engineering background. For seaplane landing, recycling for the satellite re-entry capsule, and the impact load of the bow in the adverse sea conditions, the slamming problem always plays the important role. Due to its strong nonlinear effect, however, it seems to be not easy to obtain the accurate simulation results. Combined with the strong interaction between the fluid field and the elastic structure, the difficulty for the simulation leads to a new level for challenging. This paper presents a fully Lagrangian coupled solver for simulations of fluid-structure interactions, which is based on the Moving Particle Semi-implicit (MPS) method to solve the governing equations corresponding to incompressible flows as well as elastic structures. The developed solver is verified by reproducing the high velocity impact loads of deformable thin wedges with two different materials such as aluminum and steel on water entry. The present simulation results are compared with analytical solution derived using the hydrodynamic Wagner model and linear theory by Wan.

Keywords: fluid-structure interaction, moving particle semi-implicit (MPS) method, elastic structure, incompressible flow, wedge slamming impact

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6820 A Machine Learning Approach for Anomaly Detection in Environmental IoT-Driven Wastewater Purification Systems

Authors: Giovanni Cicceri, Roberta Maisano, Nathalie Morey, Salvatore Distefano

Abstract:

The main goal of this paper is to present a solution for a water purification system based on an Environmental Internet of Things (EIoT) platform to monitor and control water quality and machine learning (ML) models to support decision making and speed up the processes of purification of water. A real case study has been implemented by deploying an EIoT platform and a network of devices, called Gramb meters and belonging to the Gramb project, on wastewater purification systems located in Calabria, south of Italy. The data thus collected are used to control the wastewater quality, detect anomalies and predict the behaviour of the purification system. To this extent, three different statistical and machine learning models have been adopted and thus compared: Autoregressive Integrated Moving Average (ARIMA), Long Short Term Memory (LSTM) autoencoder, and Facebook Prophet (FP). The results demonstrated that the ML solution (LSTM) out-perform classical statistical approaches (ARIMA, FP), in terms of both accuracy, efficiency and effectiveness in monitoring and controlling the wastewater purification processes.

Keywords: environmental internet of things, EIoT, machine learning, anomaly detection, environment monitoring

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6819 An Empirical Study of the Best Fitting Probability Distributions for Stock Returns Modeling

Authors: Jayanta Pokharel, Gokarna Aryal, Netra Kanaal, Chris Tsokos

Abstract:

Investment in stocks and shares aims to seek potential gains while weighing the risk of future needs, such as retirement, children's education etc. Analysis of the behavior of the stock market returns and making prediction is important for investors to mitigate risk on investment. Historically, the normal variance models have been used to describe the behavior of stock market returns. However, the returns of the financial assets are actually skewed with higher kurtosis, heavier tails, and a higher center than the normal distribution. The Laplace distribution and its family are natural candidates for modeling stock returns. The Variance-Gamma (VG) distribution is the most sought-after distributions for modeling asset returns and has been extensively discussed in financial literatures. In this paper, it explore the other Laplace family, such as Asymmetric Laplace, Skewed Laplace, Kumaraswamy Laplace (KS) together with Variance-Gamma to model the weekly returns of the S&P 500 Index and it's eleven business sector indices. The method of maximum likelihood is employed to estimate the parameters of the distributions and our empirical inquiry shows that the Kumaraswamy Laplace distribution performs much better for stock returns modeling among the choice of distributions used in this study and in practice, KS can be used as a strong alternative to VG distribution.

Keywords: stock returns, variance-gamma, kumaraswamy laplace, maximum likelihood

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6818 Scrum Challenges and Mitigation Practices in Global Software Development of an Integrated Learning Environment: Case Study of Science, Technology, Innovation, Mathematics, Engineering for the Young

Authors: Evgeniia Surkova, Manal Assaad, Hleb Makeyeu, Juho Makio

Abstract:

The main objective of STIMEY (Science, Technology, Innovation, Mathematics, Engineering for the Young) project is the delivery of a hybrid learning environment that combines multi-level components such as social media concepts, robotic artefacts, and radio, among others. It is based on a well-researched pedagogical framework to attract European youths to STEM (science, technology, engineering, and mathematics) education and careers. To develop and integrate these various components, STIMEY is executed in iterative research cycles leading to progressive improvements. Scrum was the development methodology of choice in the project, as studies indicated its benefits as an agile methodology in global software development, especially of e-learning and integrated learning projects. This paper describes the project partners’ experience with the Scrum framework, discussing the challenges faced in its implementation and the mitigation practices employed. The authors conclude with exploring user experience tools and principles for future research, as a novel direction in supporting the Scrum development team.

Keywords: e-learning, global software development, scrum, STEM education

Procedia PDF Downloads 166