Search results for: single and multi-objective function
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8917

Search results for: single and multi-objective function

1867 Application of Biomimetic Approach in Optimizing Buildings Heat Regulating System Using Parametric Design Tools to Achieve Thermal Comfort in Indoor Spaces in Hot Arid Regions

Authors: Aya M. H. Eissa, Ayman H. A. Mahmoud

Abstract:

When it comes to energy efficient thermal regulation system, natural systems do not only offer an inspirational source of innovative strategies but also sustainable and even regenerative ones. Using biomimetic design an energy efficient thermal regulation system can be developed. Although, conventional design process methods achieved fairly efficient systems, they still had limitations which can be overcome by using parametric design software. Accordingly, the main objective of this study is to apply and assess the efficiency of heat regulation strategies inspired from termite mounds in residential buildings’ thermal regulation system. Parametric design software is used to pave the way for further and more complex biomimetic design studies and implementations. A hot arid region is selected due to the deficiency of research in this climatic region. First, the analysis phase in which the stimuli, affecting, and the parameters, to be optimized, are set mimicking the natural system. Then, based on climatic data and using parametric design software Grasshopper, building form and openings height and areas are altered till settling on an optimized solution. Finally, an assessment of the efficiency of the optimized system, in comparison with a conventional system, is determined by firstly, indoors airflow and indoors temperature, by Ansys Fluent (CFD) simulation. Secondly by and total solar radiation falling on the building envelope, which was calculated using Ladybug, Grasshopper plugin. The results show an increase in the average indoor airflow speed from 0.5m/s to 1.5 m/s. Also, a slight decrease in temperature was noticed. And finally, the total radiation was decreased by 4%. In conclusion, despite the fact that applying a single bio-inspired heat regulation strategy might not be enough to achieve an optimum system, the concluded system is more energy efficient than the conventional ones as it aids achieving indoors comfort through passive techniques. Thus demonstrating the potential of parametric design software in biomimetic design.

Keywords: biomimicry, heat regulation systems, hot arid regions, parametric design, thermal comfort

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1866 An Overview of Posterior Fossa Associated Pathologies and Segmentation

Authors: Samuel J. Ahmad, Michael Zhu, Andrew J. Kobets

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Segmentation tools continue to advance, evolving from manual methods to automated contouring technologies utilizing convolutional neural networks. These techniques have evaluated ventricular and hemorrhagic volumes in the past but may be applied in novel ways to assess posterior fossa-associated pathologies such as Chiari malformations. Herein, we summarize literature pertaining to segmentation in the context of this and other posterior fossa-based diseases such as trigeminal neuralgia, hemifacial spasm, and posterior fossa syndrome. A literature search for volumetric analysis of the posterior fossa identified 27 papers where semi-automated, automated, manual segmentation, linear measurement-based formulas, and the Cavalieri estimator were utilized. These studies produced superior data than older methods utilizing formulas for rough volumetric estimations. The most commonly used segmentation technique was semi-automated segmentation (12 studies). Manual segmentation was the second most common technique (7 studies). Automated segmentation techniques (4 studies) and the Cavalieri estimator (3 studies), a point-counting method that uses a grid of points to estimate the volume of a region, were the next most commonly used techniques. The least commonly utilized segmentation technique was linear measurement-based formulas (1 study). Semi-automated segmentation produced accurate, reproducible results. However, it is apparent that there does not exist a single semi-automated software, open source or otherwise, that has been widely applied to the posterior fossa. Fully-automated segmentation via such open source software as FSL and Freesurfer produced highly accurate posterior fossa segmentations. Various forms of segmentation have been used to assess posterior fossa pathologies and each has its advantages and disadvantages. According to our results, semi-automated segmentation is the predominant method. However, atlas-based automated segmentation is an extremely promising method that produces accurate results. Future evolution of segmentation technologies will undoubtedly yield superior results, which may be applied to posterior fossa related pathologies. Medical professionals will save time and effort analyzing large sets of data due to these advances.

Keywords: chiari, posterior fossa, segmentation, volumetric

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1865 Hemispheric Locus and Gender Predict the Delay between the Moment of Stroke and Hospitalization

Authors: D. Anderlini, G. Wallis

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Background: The number of people experiencing stroke is steadily increasing due to changes in diet and lifestyle, to longer life expectancy resulting in older population, to higher survival rates as a consequence of improvements during the acute phase. This study considers what risk factors might contribute to delayed entry to hospital for treatment. Methods: We analyzed data from 2472 patients admitted to the Stroke Unit of the Royal Brisbane Women's Hospital, Australia, between 2002 to 2011. Results: Previous studies have reported that factors which can contribute to delay include the patient’s age, the time of day, physical location, visit the GP instead of going to the emergency, means of transport, severity of symptoms and type of stroke. Contrary to findings of other studies, we found a strong correlation between side of lesion and delay in admission: patients with right hemisphere lesions had an average delay of 3.78 days, while patients with left hemisphere lesions had an average delay of 1.49 days. Damage to the right hemisphere generally ends in motor impairment in the non-dominant hand and no speech impediment. In contrast, left hemisphere lesions can result in deficit to; dominant hand function and aphasia which will be noticed even if their impact on performance is relatively minor. A finding which goes against many previous studies, is the fact that women get to the hospital much sooner than men, showing an average delay of 0.92 days in women vs. 3.36 days in men. Conclusion: Acute surgical-pharmacological therapies are most effective if applied immediately after stroke. Hence delays to admission can be crucial to the degree of recovery. The tendency of patients to overlook symptoms of right hemisphere lesion should be the target of information campaigns both for the general public and GPs. Why do men go to hospital so late? We don't know yet! Nevertheless an awareness plan specifically direct to male population should be on the agenda of Health Departments.

Keywords: gender, admission delay, stroke location, bioinformatics, biomedicine

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1864 The Role of Immunologic Diamonds in Dealing with Mycobacterium Tuberculosis; Responses of Immune Cells in Affliction to the Respiratory Tuberculosis

Authors: Seyyed Mohammad Amin Mousavi Sagharchi, Elham Javanroudi

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Introduction: Tuberculosis (TB) is a known disease with hidden features caused by Mycobacterium tuberculosis (MTB). This disease, which is one of the 10 deadliest in the world, has caused millions of deaths in recent decades. Furthermore, TB is responsible for infecting about 30% population of world. Like any infection, TB can activate the immune system by locating and colonization in the human body, especially in the alveoli. TB is granulomatosis, so MTB can absorb the host’s immune cells and other cells to form granuloma. Method: Different databases (e.g., PubMed) were recruited to prepare this paper and fulfill our goals to search and find effective papers and investigations. Results: Immune response to MTB is related to T cell killers and contains CD1, CD4, and CD8 T lymphocytes. CD1 lymphocytes can recognize glycolipids, which highly exist in the Mycobacterial fatty cell wall. CD4 lymphocytes and macrophages form granuloma, and it is the main line of immune response to Mycobacteria. On the other hand, CD8 cells have cytolytic function for directly killing MTB by secretion of granulysin. Other functions and secretion to the deal are interleukin-12 (IL-12) by induction of expression interferon-γ (INF-γ) for macrophages activation and creating a granuloma, and tumor necrosis factor (TNF) by promoting macrophage phagolysosomal fusion. Conclusion: Immune cells in battle with MTB are macrophages, dendritic cells (DCs), neutrophils, and natural killer (NK) cells. These immune cells can recognize the Mycobacterium by various receptors, including Toll-like receptors (TLRs), Nod-like receptors (NLRs), and C-type lectin receptors (CLRs) located in the cell surface. In human alveoli exist about 50 dendritic macrophages, which have close communication with other immune cells in the circulating system and epithelial cells to deal with Mycobacteria. Against immune cells, MTB handles some factors (e.g., cordfactor, O-Ag, lipoarabinomannan, sulfatides, and adenylate cyclase) and practical functions (e.g., inhibition of macrophages).

Keywords: mycobacterium tuberculosis, immune responses, immunological mechanisms, respiratory tuberculosis

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1863 Boundary Layer Control Using a Magnetic Field: A Case Study in the Framework of Ferrohydrodynamics

Authors: C. F. Alegretti, F. R. Cunha, R. G. Gontijo

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This work investigates the effects of an applied magnetic field on the geometry-driven boundary layer detachment flow of a ferrofluid over a sudden expansion. Both constitutive equation and global magnetization equation for a ferrofluid are considered. Therefore, the proposed formulation consists in a coupled magnetic-hydrodynamic problem. Computational simulations are carried out in order to explore, not only the viability to control flow instabilities, but also to evaluate the consistency of theoretical aspects. The unidirectional sudden expansion in a ferrofluid flow is investigated numerically under the perspective of Ferrohydrodynamics in a two-dimensional domain using a Finite Differences Method. The boundary layer detachment induced by the sudden expansion results in a recirculating zone, which has been extensively studied in non-magnetic hydrodynamic problems for a wide range of Reynolds numbers. Similar investigations can be found in literature regarding the sudden expansion under the magnetohydrodynamics framework, but none considering a colloidal suspension of magnetic particles out of the superparamagnetic regime. The vorticity-stream function formulation is implemented and results in a clear coupling between the flow vorticity and its magnetization field. Our simulations indicate a systematic decay on the length of the recirculation zone as increasing physical parameters of the flow, such as the intensity of the applied field and the volume fraction of particles. The results all are discussed from a physical point of view in terms of the dynamical non-dimensional parameters. We argue that the decrease/reduction in the recirculation region of the flow is a direct consequence of the magnetic torque balancing the action of the torque produced by viscous and inertial forces of the flow. For the limit of small Reynolds and magnetic Reynolds parameters, the diffusion of vorticity balances the diffusion of the magnetic torque on the flow. These mechanics control the growth of the recirculation region.

Keywords: boundary layer detachment, ferrofluid, ferrohydrodynamics, magnetization, sudden expansion

Procedia PDF Downloads 184
1862 Investigation of Nucleation and Thermal Conductivity of Waxy Crude Oil on Pipe Wall via Particle Dynamics

Authors: Jinchen Cao, Tiantian Du

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As waxy crude oil is easy to crystallization and deposition in the pipeline wall, it causes pipeline clogging and leads to the reduction of oil and gas gathering and transmission efficiency. In this paper, a mesoscopic scale dissipative particle dynamics method is employed, and constructed four pipe wall models, including smooth wall (SW), hydroxylated wall (HW), rough wall (RW), and single-layer graphene wall (GW). Snapshots of the simulation output trajectories show that paraffin molecules interact with each other to form a network structure that constrains water molecules as their nucleation sites. Meanwhile, it is observed that the paraffin molecules on the near-wall side are adsorbed horizontally between inter-lattice gaps of the solid wall. In the pressure range of 0 - 50 MPa, the pressure change has less effect on the affinity properties of SS, HS, and GS walls, but for RS walls, the contact angle between paraffin wax and water molecules was found to decrease with the increase in pressure, while the water molecules showed the opposite trend, the phenomenon is due to the change in pressure, leading to the transition of paraffin wax molecules from amorphous to crystalline state. Meanwhile, the minimum crystalline phase pressure (MCPP) was proposed to describe the lowest pressure at which crystallization of paraffin molecules occurs. The maximum number of crystalline clusters formed by paraffin molecules at MCPP in the system showed NSS (0.52 MPa) > NHS (0.55 MPa) > NRS (0.62 MPa) > NGS (0.75 MPa). The MCPP on the graphene surface, with the least number of clusters formed, indicates that the addition of graphene inhibited the crystallization process of paraffin deposition on the wall surface. Finally, the thermal conductivity was calculated, and the results show that on the near-wall side, the thermal conductivity changes drastically due to the occurrence of adsorption crystallization of paraffin waxes; on the fluid side the thermal conductivity gradually tends to stabilize, and the average thermal conductivity shows: ĸRS(0.254W/(m·K)) > ĸRS(0.249W/(m·K)) > ĸRS(0.218W/(m·K)) > ĸRS(0.188W/(m·K)).This study provides a theoretical basis for improving the transport efficiency and heat transfer characteristics of waxy crude oil in terms of wall type, wall roughness, and MCPP.

Keywords: waxy crude oil, thermal conductivity, crystallization, dissipative particle dynamics, MCPP

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1861 Latent Heat Storage Using Phase Change Materials

Authors: Debashree Ghosh, Preethi Sridhar, Shloka Atul Dhavle

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The judicious and economic consumption of energy for sustainable growth and development is nowadays a thing of primary importance; Phase Change Materials (PCM) provide an ingenious option of storing energy in the form of Latent Heat. Energy storing mechanism incorporating phase change material increases the efficiency of the process by minimizing the difference between supply and demand; PCM heat exchangers are used to storing the heat or non-convectional energy within the PCM as the heat of fusion. The experimental study evaluates the effect of thermo-physical properties, variation in inlet temperature, and flow rate on charging period of a coiled heat exchanger. Secondly, a numerical study is performed on a PCM double pipe heat exchanger packed with two different PCMs, namely, RT50 and Fatty Acid, in the annular region. In this work, the simulation of charging of paraffin wax (RT50) using water as high-temperature fluid (HTF) is performed. Commercial software Ansys-Fluent 15 is used for simulation, and hence charging of PCM is studied. In the Enthalpy-porosity model, a single momentum equation is applicable to describe the motion of both solid and liquid phases. The details of the progress of phase change with time are presented through the contours of melt-fraction, temperature. The velocity contour is shown to describe the motion of the liquid phase. The experimental study revealed that paraffin wax melts with almost the same temperature variation at the two Intermediate positions. Fatty acid, on the other hand, melts faster owing to greater thermal conductivity and low melting temperature. It was also observed that an increase in flow rate leads to a reduction in the charging period. The numerical study also supports some of the observations found in the experimental study like the significant dependence of driving force on the process of melting. The numerical study also clarifies the melting pattern of the PCM, which cannot be observed in the experimental study.

Keywords: latent heat storage, charging period, discharging period, coiled heat exchanger

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1860 The Effect of Health Promoting Programs on Patient's Life Style after Coronary Artery Bypass Graft–Hospitalized in Shiraz Hospitals

Authors: Azizollah Arbabisarjou, Leila Safabakhsh, Mozhgan Jahantigh, Mahshid Nazemzadeh, Shahindokht Navabi

Abstract:

Background: Health promotion is an essential strategy for reduction of health disparities. Health promotion includes all activities that encourage optimum physical, spiritual, and mental function. The aim of this study was to determine the impact of a Health Promotion Program (HPP) on behavior in terms of the dimensions of the Health Promoting Lifestyle Profile (HPLP) in patients after Coronary Artery Bypass Graft (CABG). Methods and Materials: In this clinical trial study, 80 patients who had undergone CABG surgery (2011-2012) were selected and randomly divided in two groups: Experimental and Control that investigated by (HPLP II). Then the experimental group was educated about diet, walking and stress management. The program process was followed up for 3months and after that all variables were investigated again. The overall score and the scores for the six dimensions of the HPLP (self-actualization, health responsibility, exercise, nutrition, interpersonal support and stress management) were measured in the pre- and post-test periods. Statistical analysis was performed using Student's t-test and paired t-test. Results: Results showed that Score of stress management (p=.036), diet (p=.002), Spiritual Growth (p=.001) and interrelationship (p=002) increase in experimental group after intervention .Average scores after 3 months in the control group had no significant changes; except responsibility for health (p < .05). Results of the study revealed that comparison the scores of the experimental group were significantly different from the control group in all lifestyle aspects except for spiritual growth. Conclusion: This study showed that Health promoting program on lifestyle and health promotion in patients who suffer from CAD could enhance patient's awareness of healthy behaviors and improves the quality of life.

Keywords: coronary artery bypass graft, health promotion, lifestyle, education

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1859 Sociolinguistic and Classroom Functions of Using Code-Switching in CLIL Context

Authors: Khatuna Buskivadze

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The aim of the present study is to investigate the sociolinguistic and classroom functions and frequency of Teacher’s Code Switching (CS) in the Content and Language Integrated (CLIL) Lesson. Nowadays, Georgian society struggles to become the part of the European world, the English language itself plays a role in forming new generations with European values. Based on our research conducted in 2019, out of all 114 private schools in Tbilisi, full- programs of CLIL are taught in 7 schools, while only some subjects using CLIL are conducted in 3 schools. The goal of the former research was to define the features of Content and Language Integrated learning (CLIL) methodology within the process of teaching English on the Example of Georgian private high schools. Taking the Georgian reality and cultural features into account, the modified version of the questionnaire, based on the classification of using CS in ESL Classroom proposed By Ferguson (2009) was used. The qualitative research revealed students’ and teacher’s attitudes towards teacher’s code-switching in CLIL lesson. Both qualitative and quantitative research were conducted: the observations of the teacher’s lessons (Recording of T’s online lessons), interview and the questionnaire among Math’s T’s 20 high school students. We came to the several conclusions, some of them are given here: Math’s teacher’s CS behavior mostly serves (1) the conversational function of interjection; (2) the classroom functions of introducing unfamiliar materials and topics, explaining difficult concepts, maintaining classroom discipline and the structure of the lesson; The teacher and 13 students have negative attitudes towards using only Georgian in teaching Math. The higher level of English is the more negative is attitude towards using Georgian in the classroom. Although all the students were Georgian, their competence in English is higher than in Georgian, therefore they consider English as an inseparable part of their identities. The overall results of the case study of teaching Math (Educational discourse) in one of the private schools in Tbilisi will be presented at the conference.

Keywords: attitudes, bilingualism, code-switching, CLIL, conversation analysis, interactional sociolinguistics.

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1858 Colour and Travel: Design of an Innovative Infrastructure for Travel Applications with Entertaining and Playful Features

Authors: Avrokomi Zavitsanou, Spiros Papadopoulos, Theofanis Alexandridis

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This paper presents the research project ‘Colour & Travel’, which is co-funded by the European Union and national resources through the Operational Programme “Competitiveness, Entrepreneurship and Innovation” 2014-2020, under the Single RTDI State Aid Action "RESEARCH - CREATE - INNOVATE". The research project proposes the design of an innovative, playful framework for exploring a variety of travel destinations and creating personalised travel narratives, aiming to entertain, educate, and promote culture and tourism. Gamification of the cultural and touristic environment can enhance its experiential, multi-sensory aspects and broaden the perception of the traveler. The latter's involvement in creating and shaping his personal travel narrations and the possibility of sharing it with others can offer him an alternative, more binding way of getting acquainted with a place. In particular, the paper presents the design of an infrastructure: (a) for the development of interactive travel guides for mobile devices, where sites with specific points of interest will be recommended, with which the user can interact in playful ways and then create his personal travel narratives, (b) for the development of innovative games within virtual reality environment, where the interaction will be offered while the user is moving within the virtual environment; and (c) for an online application where the content will be offered through the browser and the modern 3D imaging technologies (WebGL). The technological products that will be developed within the proposed project can strengthen important sectors of economic and social life, such as trade, tourism, exploitation and promotion of the cultural environment, creative industries, etc. The final applications delivered at the end of the project will guarantee an improved level of service for visitors and will be a useful tool for content creators with increased adaptability, expansibility, and applicability in many regions of Greece and abroad. This paper aims to present the research project by referencing the state of the art and the methodological scheme, ending with a brief reflection on the expected outcome in terms of results.

Keywords: gamification, culture, tourism, AR, VR, applications

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1857 Simultaneous Determination of Methotrexate and Aspirin Using Fourier Transform Convolution Emission Data under Non-Parametric Linear Regression Method

Authors: Marwa A. A. Ragab, Hadir M. Maher, Eman I. El-Kimary

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Co-administration of methotrexate (MTX) and aspirin (ASP) can cause a pharmacokinetic interaction and a subsequent increase in blood MTX concentrations which may increase the risk of MTX toxicity. Therefore, it is important to develop a sensitive, selective, accurate and precise method for their simultaneous determination in urine. A new hybrid chemometric method has been applied to the emission response data of the two drugs. Spectrofluorimetric method for determination of MTX through measurement of its acid-degradation product, 4-amino-4-deoxy-10-methylpteroic acid (4-AMP), was developed. Moreover, the acid-catalyzed degradation reaction enables the spectrofluorimetric determination of ASP through the formation of its active metabolite salicylic acid (SA). The proposed chemometric method deals with convolution of emission data using 8-points sin xi polynomials (discrete Fourier functions) after the derivative treatment of these emission data. The first and second derivative curves (D1 & D2) were obtained first then convolution of these curves was done to obtain first and second derivative under Fourier functions curves (D1/FF) and (D2/FF). This new application was used for the resolution of the overlapped emission bands of the degradation products of both drugs to allow their simultaneous indirect determination in human urine. Not only this chemometric approach was applied to the emission data but also the obtained data were subjected to non-parametric linear regression analysis (Theil’s method). The proposed method was fully validated according to the ICH guidelines and it yielded linearity ranges as follows: 0.05-0.75 and 0.5-2.5 µg mL-1 for MTX and ASP respectively. It was found that the non-parametric method was superior over the parametric one in the simultaneous determination of MTX and ASP after the chemometric treatment of the emission spectra of their degradation products. The work combines the advantages of derivative and convolution using discrete Fourier function together with the reliability and efficacy of the non-parametric analysis of data. The achieved sensitivity along with the low values of LOD (0.01 and 0.06 µg mL-1) and LOQ (0.04 and 0.2 µg mL-1) for MTX and ASP respectively, by the second derivative under Fourier functions (D2/FF) were promising and guarantee its application for monitoring the two drugs in patients’ urine samples.

Keywords: chemometrics, emission curves, derivative, convolution, Fourier transform, human urine, non-parametric regression, Theil’s method

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1856 Structural Design Optimization of Reinforced Thin-Walled Vessels under External Pressure Using Simulation and Machine Learning Classification Algorithm

Authors: Lydia Novozhilova, Vladimir Urazhdin

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An optimization problem for reinforced thin-walled vessels under uniform external pressure is considered. The conventional approaches to optimization generally start with pre-defined geometric parameters of the vessels, and then employ analytic or numeric calculations and/or experimental testing to verify functionality, such as stability under the projected conditions. The proposed approach consists of two steps. First, the feasibility domain will be identified in the multidimensional parameter space. Every point in the feasibility domain defines a design satisfying both geometric and functional constraints. Second, an objective function defined in this domain is formulated and optimized. The broader applicability of the suggested methodology is maximized by implementing the Support Vector Machines (SVM) classification algorithm of machine learning for identification of the feasible design region. Training data for SVM classifier is obtained using the Simulation package of SOLIDWORKS®. Based on the data, the SVM algorithm produces a curvilinear boundary separating admissible and not admissible sets of design parameters with maximal margins. Then optimization of the vessel parameters in the feasibility domain is performed using the standard algorithms for the constrained optimization. As an example, optimization of a ring-stiffened closed cylindrical thin-walled vessel with semi-spherical caps under high external pressure is implemented. As a functional constraint, von Mises stress criterion is used but any other stability constraint admitting mathematical formulation can be incorporated into the proposed approach. Suggested methodology has a good potential for reducing design time for finding optimal parameters of thin-walled vessels under uniform external pressure.

Keywords: design parameters, feasibility domain, von Mises stress criterion, Support Vector Machine (SVM) classifier

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1855 Cryptic Diversity: Identifying Two Morphologically Similar Species of Invasive Apple Snails in Peninsular Malaysia

Authors: Suganiya Rama Rao, Yoon-Yen Yow, Thor-Seng Liew, Shyamala Ratnayeke

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Invasive snails in the genus Pomacea have spread across Southeast Asia including Peninsular Malaysia. Apart from significant economic costs to wetland crops, very little is known about the snails’ effects on native species, and wetland function through their alteration of macrophyte communities. This study was conducted to establish diagnostic characteristics of Pomacea species in the Malaysian environment using genetic and morphological criteria. Snails were collected from eight localities in northern and central regions of Peninsular Malaysia. The mitochondrial COI gene of 52 adult snails was amplified and sequenced. Maximum likelihood analysis was used to analyse species identity and assess phylogenetic relationships among snails from different geographic locations. Shells of the two species were compared using geometric morphometric analysis and covariance analyses. Shell height accounted for most of the observed variation between P. canaliculata and P. maculata, with the latter possessing a smaller mean ratio of shell height: aperture height (p < 0.0001) and shell height to shell width (give p < 0.0001). Genomic and phylogenetic analysis demonstrated the presence of two monophyletic taxa, P. canaliculata and P. maculata, in Peninsular Malaysia samples. P. maculata co-occurred with P. canaliculata in 5 localities, but samples from 3 localities contained only P. canaliculata. This study is the first to confirm the presence of two of the most invasive species of Pomacea in Peninsular Malaysia using a genomic approach. P. canaliculata appears to be the more widespread species. Despite statistical differences, both quantitative and qualitative morphological characteristics demonstrate much interspecific overlap and intraspecific variability; thus morphology alone cannot reliably verify species identity. Molecular techniques for distinguishing between these two highly invasive Pomacea species are needed to understand their specific ecological niches and develop effective protocols for their management.

Keywords: Pomacea canaliculata, Pomacea maculata, invasive species, phylog enetic analysis, geometric morphometric analysis

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1854 Robust Numerical Solution for Flow Problems

Authors: Gregor Kosec

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Simple and robust numerical approach for solving flow problems is presented, where involved physical fields are represented through the local approximation functions, i.e., the considered field is approximated over a local support domain. The approximation functions are then used to evaluate the partial differential operators. The type of approximation, the size of support domain, and the type and number of basis function can be general. The solution procedure is formulated completely through local computational operations. Besides local numerical method also the pressure velocity is performed locally with retaining the correct temporal transient. The complete locality of the introduced numerical scheme has several beneficial effects. One of the most attractive is the simplicity since it could be understood as a generalized Finite Differences Method, however, much more powerful. Presented methodology offers many possibilities for treating challenging cases, e.g. nodal adaptivity to address regions with sharp discontinuities or p-adaptivity to treat obscure anomalies in physical field. The stability versus computation complexity and accuracy can be regulated by changing number of support nodes, etc. All these features can be controlled on the fly during the simulation. The presented methodology is relatively simple to understand and implement, which makes it potentially powerful tool for engineering simulations. Besides simplicity and straightforward implementation, there are many opportunities to fully exploit modern computer architectures through different parallel computing strategies. The performance of the method is presented on the lid driven cavity problem, backward facing step problem, de Vahl Davis natural convection test, extended also to low Prandtl fluid and Darcy porous flow. Results are presented in terms of velocity profiles, convergence plots, and stability analyses. Results of all cases are also compared against published data.

Keywords: fluid flow, meshless, low Pr problem, natural convection

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1853 Lead Chalcogenide Quantum Dots for Use in Radiation Detectors

Authors: Tom Nakotte, Hongmei Luo

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Lead chalcogenide-based (PbS, PbSe, and PbTe) quantum dots (QDs) were synthesized for the purpose of implementing them in radiation detectors. Pb based materials have long been of interest for gamma and x-ray detection due to its high absorption cross section and Z number. The emphasis of the studies was on exploring how to control charge carrier transport within thin films containing the QDs. The properties of QDs itself can be altered by changing the size, shape, composition, and surface chemistry of the dots, while the properties of carrier transport within QD films are affected by post-deposition treatment of the films. The QDs were synthesized using colloidal synthesis methods and films were grown using multiple film coating techniques, such as spin coating and doctor blading. Current QD radiation detectors are based on the QD acting as fluorophores in a scintillation detector. Here the viability of using QDs in solid-state radiation detectors, for which the incident detectable radiation causes a direct electronic response within the QD film is explored. Achieving high sensitivity and accurate energy quantification in QD radiation detectors requires a large carrier mobility and diffusion lengths in the QD films. Pb chalcogenides-based QDs were synthesized with both traditional oleic acid ligands as well as more weakly binding oleylamine ligands, allowing for in-solution ligand exchange making the deposition of thick films in a single step possible. The PbS and PbSe QDs showed better air stability than PbTe. After precipitation the QDs passivated with the shorter ligand are dispersed in 2,6-difloupyridine resulting in colloidal solutions with concentrations anywhere from 10-100 mg/mL for film processing applications, More concentrated colloidal solutions produce thicker films during spin-coating, while an extremely concentrated solution (100 mg/mL) can be used to produce several micrometer thick films using doctor blading. Film thicknesses of micrometer or even millimeters are needed for radiation detector for high-energy gamma rays, which are of interest for astrophysics or nuclear security, in order to provide sufficient stopping power.

Keywords: colloidal synthesis, lead chalcogenide, radiation detectors, quantum dots

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1852 Uncertainty Quantification of Corrosion Anomaly Length of Oil and Gas Steel Pipelines Based on Inline Inspection and Field Data

Authors: Tammeen Siraj, Wenxing Zhou, Terry Huang, Mohammad Al-Amin

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The high resolution inline inspection (ILI) tool is used extensively in the pipeline industry to identify, locate, and measure metal-loss corrosion anomalies on buried oil and gas steel pipelines. Corrosion anomalies may occur singly (i.e. individual anomalies) or as clusters (i.e. a colony of corrosion anomalies). Although the ILI technology has advanced immensely, there are measurement errors associated with the sizes of corrosion anomalies reported by ILI tools due limitations of the tools and associated sizing algorithms, and detection threshold of the tools (i.e. the minimum detectable feature dimension). Quantifying the measurement error in the ILI data is crucial for corrosion management and developing maintenance strategies that satisfy the safety and economic constraints. Studies on the measurement error associated with the length of the corrosion anomalies (in the longitudinal direction of the pipeline) has been scarcely reported in the literature and will be investigated in the present study. Limitations in the ILI tool and clustering process can sometimes cause clustering error, which is defined as the error introduced during the clustering process by including or excluding a single or group of anomalies in or from a cluster. Clustering error has been found to be one of the biggest contributory factors for relatively high uncertainties associated with ILI reported anomaly length. As such, this study focuses on developing a consistent and comprehensive framework to quantify the measurement errors in the ILI-reported anomaly length by comparing the ILI data and corresponding field measurements for individual and clustered corrosion anomalies. The analysis carried out in this study is based on the ILI and field measurement data for a set of anomalies collected from two segments of a buried natural gas pipeline currently in service in Alberta, Canada. Data analyses showed that the measurement error associated with the ILI-reported length of the anomalies without clustering error, denoted as Type I anomalies is markedly less than that for anomalies with clustering error, denoted as Type II anomalies. A methodology employing data mining techniques is further proposed to classify the Type I and Type II anomalies based on the ILI-reported corrosion anomaly information.

Keywords: clustered corrosion anomaly, corrosion anomaly assessment, corrosion anomaly length, individual corrosion anomaly, metal-loss corrosion, oil and gas steel pipeline

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1851 Dynamic Test for Stability of Bar Loaded by a Compression Force Directed Towards the Pole

Authors: Elia Efraim, Boris Blostotsky

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The phenomenon of buckling of structural elements under compression is revealed in many cases of loading and found consideration in many structures and mechanisms. In the present work the method and results of dynamic test for buckling of bar loaded by a compression force directed towards the pole are considered. Experimental determination of critical force for such system has not been made previously. The tested object is a bar with semi-rigid connection to the base at one of its ends, and with a hinge moving along a circle at the other. The test includes measuring the natural frequency of the bar at different values of compression load. The lateral stiffness is calculated based on natural frequency and reduced mass on the bar's movable end. The critical load is determined by extrapolation the values of lateral stiffness up to zero value. For the experimental investigation the special test-bed was created that allows the stability testing at positive and negative curvature of the movable end's trajectory, as well as varying the rotational stiffness of the other end connection. Decreasing a friction at the movable end allows extend the diapason of applied compression force. The testing method includes : - methodology of the experiment planning, that allows determine the required number of tests under various loads values in the defined range and the type of extrapolating function; - methodology of experimental determination of reduced mass at the bar's movable end including its own mass; - methodology of experimental determination of lateral stiffness of uncompressed bar rotational semi-rigid connection at the base. For planning the experiment and for comparison of the experimental results with the theoretical values of critical load, the analytical dependencies of lateral stiffness of the bar with defined end conditions on compression load. In the particular case of perfectly rigid connection of the bar to the base, the critical load value corresponds to solution by S.P. Timoshenko. Correspondence of the calculated and experimental values was obtained.

Keywords: buckling, dynamic method, end-fixity factor, force directed towards a pole

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1850 Joint Training Offer Selection and Course Timetabling Problems: Models and Algorithms

Authors: Gianpaolo Ghiani, Emanuela Guerriero, Emanuele Manni, Alessandro Romano

Abstract:

In this article, we deal with a variant of the classical course timetabling problem that has a practical application in many areas of education. In particular, in this paper we are interested in high schools remedial courses. The purpose of such courses is to provide under-prepared students with the skills necessary to succeed in their studies. In particular, a student might be under prepared in an entire course, or only in a part of it. The limited availability of funds, as well as the limited amount of time and teachers at disposal, often requires schools to choose which courses and/or which teaching units to activate. Thus, schools need to model the training offer and the related timetabling, with the goal of ensuring the highest possible teaching quality, by meeting the above-mentioned financial, time and resources constraints. Moreover, there are some prerequisites between the teaching units that must be satisfied. We first present a Mixed-Integer Programming (MIP) model to solve this problem to optimality. However, the presence of many peculiar constraints contributes inevitably in increasing the complexity of the mathematical model. Thus, solving it through a general purpose solver may be performed for small instances only, while solving real-life-sized instances of such model requires specific techniques or heuristic approaches. For this purpose, we also propose a heuristic approach, in which we make use of a fast constructive procedure to obtain a feasible solution. To assess our exact and heuristic approaches we perform extensive computational results on both real-life instances (obtained from a high school in Lecce, Italy) and randomly generated instances. Our tests show that the MIP model is never solved to optimality, with an average optimality gap of 57%. On the other hand, the heuristic algorithm is much faster (in about the 50% of the considered instances it converges in approximately half of the time limit) and in many cases allows achieving an improvement on the objective function value obtained by the MIP model. Such an improvement ranges between 18% and 66%.

Keywords: heuristic, MIP model, remedial course, school, timetabling

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1849 Kernel-Based Double Nearest Proportion Feature Extraction for Hyperspectral Image Classification

Authors: Hung-Sheng Lin, Cheng-Hsuan Li

Abstract:

Over the past few years, kernel-based algorithms have been widely used to extend some linear feature extraction methods such as principal component analysis (PCA), linear discriminate analysis (LDA), and nonparametric weighted feature extraction (NWFE) to their nonlinear versions, kernel principal component analysis (KPCA), generalized discriminate analysis (GDA), and kernel nonparametric weighted feature extraction (KNWFE), respectively. These nonlinear feature extraction methods can detect nonlinear directions with the largest nonlinear variance or the largest class separability based on the given kernel function. Moreover, they have been applied to improve the target detection or the image classification of hyperspectral images. The double nearest proportion feature extraction (DNP) can effectively reduce the overlap effect and have good performance in hyperspectral image classification. The DNP structure is an extension of the k-nearest neighbor technique. For each sample, there are two corresponding nearest proportions of samples, the self-class nearest proportion and the other-class nearest proportion. The term “nearest proportion” used here consider both the local information and other more global information. With these settings, the effect of the overlap between the sample distributions can be reduced. Usually, the maximum likelihood estimator and the related unbiased estimator are not ideal estimators in high dimensional inference problems, particularly in small data-size situation. Hence, an improved estimator by shrinkage estimation (regularization) is proposed. Based on the DNP structure, LDA is included as a special case. In this paper, the kernel method is applied to extend DNP to kernel-based DNP (KDNP). In addition to the advantages of DNP, KDNP surpasses DNP in the experimental results. According to the experiments on the real hyperspectral image data sets, the classification performance of KDNP is better than that of PCA, LDA, NWFE, and their kernel versions, KPCA, GDA, and KNWFE.

Keywords: feature extraction, kernel method, double nearest proportion feature extraction, kernel double nearest feature extraction

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1848 System Identification of Building Structures with Continuous Modeling

Authors: Ruichong Zhang, Fadi Sawaged, Lotfi Gargab

Abstract:

This paper introduces a wave-based approach for system identification of high-rise building structures with a pair of seismic recordings, which can be used to evaluate structural integrity and detect damage in post-earthquake structural condition assessment. The fundamental of the approach is based on wave features of generalized impulse and frequency response functions (GIRF and GFRF), i.e., wave responses at one structural location to an impulsive motion at another reference location in time and frequency domains respectively. With a pair of seismic recordings at the two locations, GFRF is obtainable as Fourier spectral ratio of the two recordings, and GIRF is then found with the inverse Fourier transformation of GFRF. With an appropriate continuous model for the structure, a closed-form solution of GFRF, and subsequent GIRF, can also be found in terms of wave transmission and reflection coefficients, which are related to structural physical properties above the impulse location. Matching the two sets of GFRF and/or GIRF from recordings and the model helps identify structural parameters such as wave velocity or shear modulus. For illustration, this study examines ten-story Millikan Library in Pasadena, California with recordings of Yorba Linda earthquake of September 3, 2002. The building is modelled as piecewise continuous layers, with which GFRF is derived as function of such building parameters as impedance, cross-sectional area, and damping. GIRF can then be found in closed form for some special cases and numerically in general. Not only does this study reveal the influential factors of building parameters in wave features of GIRF and GRFR, it also shows some system-identification results, which are consistent with other vibration- and wave-based results. Finally, this paper discusses the effectiveness of the proposed model in system identification.

Keywords: wave-based approach, seismic responses of buildings, wave propagation in structures, construction

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1847 Optimization of Process Parameters and Modeling of Mass Transport during Hybrid Solar Drying of Paddy

Authors: Aprajeeta Jha, Punyadarshini P. Tripathy

Abstract:

Drying is one of the most critical unit operations for prolonging the shelf-life of food grains in order to ensure global food security. Photovoltaic integrated solar dryers can be a sustainable solution for replacing energy intensive thermal dryers as it is capable of drying in off-sunshine hours and provide better control over drying conditions. But, performance and reliability of PV based solar dryers depend hugely on climatic conditions thereby, drastically affecting process parameters. Therefore, to ensure quality and prolonged shelf-life of paddy, optimization of process parameters for solar dryers is critical. Proper moisture distribution within the grains is most detrimental factor to enhance the shelf-life of paddy therefore; modeling of mass transport can help in providing a better insight of moisture migration. Hence, present work aims at optimizing the process parameters and to develop a 3D finite element model (FEM) for predicting moisture profile in paddy during solar drying. Optimization of process parameters (power level, air velocity and moisture content) was done using box Behnken model in Design expert software. Furthermore, COMSOL Multiphysics was employed to develop a 3D finite element model for predicting moisture profile. Optimized model for drying paddy was found to be 700W, 2.75 m/s and 13% wb with optimum temperature, milling yield and drying time of 42˚C, 62%, 86 min respectively, having desirability of 0.905. Furthermore, 3D finite element model (FEM) for predicting moisture migration in single kernel for every time step has been developed. The mean absolute error (MAE), mean relative error (MRE) and standard error (SE) were found to be 0.003, 0.0531 and 0.0007, respectively, indicating close agreement of model with experimental results. Above optimized conditions can be successfully used to dry paddy in PV integrated solar dryer in order to attain maximum uniformity, quality and yield of product to achieve global food and energy security

Keywords: finite element modeling, hybrid solar drying, mass transport, paddy, process optimization

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1846 A Furniture Industry Concept for a Sustainable Generative Design Platform Employing Robot Based Additive Manufacturing

Authors: Andrew Fox, Tao Zhang, Yuanhong Zhao, Qingping Yang

Abstract:

The furniture manufacturing industry has been slow in general to adopt the latest manufacturing technologies, historically relying heavily upon specialised conventional machinery. This approach not only requires high levels of specialist process knowledge, training, and capital investment but also suffers from significant subtractive manufacturing waste and high logistics costs due to the requirement for centralised manufacturing, with high levels of furniture product not re-cycled or re-used. This paper aims to address the problems by introducing suitable digital manufacturing technologies to create step changes in furniture manufacturing design, as the traditional design practices have been reported as building in 80% of environmental impact. In this paper, a 3D printing robot for furniture manufacturing is reported. The 3D printing robot mainly comprises a KUKA industrial robot, an Arduino microprocessor, and a self-assembled screw fed extruder. Compared to traditional 3D printer, the 3D printing robot has larger motion range and can be easily upgraded to enlarge the maximum size of the printed object. Generative design is also investigated in this paper, aiming to establish a combined design methodology that allows assessment of goals, constraints, materials, and manufacturing processes simultaneously. ‘Matrixing’ for part amalgamation and product performance optimisation is enabled. The generative design goals of integrated waste reduction increased manufacturing efficiency, optimised product performance, and reduced environmental impact institute a truly lean and innovative future design methodology. In addition, there is massive future potential to leverage Single Minute Exchange of Die (SMED) theory through generative design post-processing of geometry for robot manufacture, resulting in ‘mass customised’ furniture with virtually no setup requirements. These generatively designed products can be manufactured using the robot based additive manufacturing. Essentially, the 3D printing robot is already functional; some initial goals have been achieved and are also presented in this paper.

Keywords: additive manufacturing, generative design, robot, sustainability

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1845 Nose Macroneedling Tie Suture Hidden Technique

Authors: Mohamed Ghoz, Hala Alsabeh

Abstract:

Context: Macroscopic Nose Macroneedling (MNM) is a new non-surgical procedure for lifting and tightening the nose. It is a tissue-non-invasive technique that uses a needle to create micro-injuries in the skin. These injuries stimulate the production of collagen and elastin, which results in the tightening and lifting of the skin. Research Aim: The research aim of this study was to investigate the efficacy and safety of MNM for the treatment of nasal deformities. Methodology A total of 100 patients with nasal deformities were included in this study. The patients were randomly assigned to either the MNM group or the control group. The MNM group received a single treatment of MNM, while the control group received no treatment. The patients were evaluated at baseline, 6 months, and 12 months after treatment. Findings: The results of this study showed that MNM was effective in improving the appearance of the nose in patients with nasal deformities. At 6 months after treatment, the patients in the MNM group had significantly improved nasal tip projection, nasal bridge height, and nasal width compared to the patients in the control group. The improvements in nasal appearance were maintained at 12 months after treatment. Theoretical Importance: The findings of this study provide support for the use of MNM as a safe and effective treatment for nasal deformities. MNM is a non-surgical procedure that is associated with minimal downtime and no risk of scarring. This makes it an attractive option for patients who are looking for a minimally invasive treatment for their nasal deformities. Data Collection: Data was collected from the patients using a variety of methods, including clinical assessments, photographic assessments, and patient-reported outcome measures. Analysis Procedures: The data was analyzed using a variety of statistical methods, including descriptive statistics, inferential statistics, and meta-analysis. Question Addressed: The research question addressed in this study was whether MNM is an effective and safe treatment for nasal deformities. Conclusion: The findings of this study suggest that MNM is an effective and safe treatment for nasal deformities. MNM is a non-surgical procedure that is associated with minimal downtime and no risk of scarring. This makes it an attractive option for patients who are looking for a minimally invasive treatment for their nasal deformities.

Keywords: nose, surgery, tie, suture

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1844 Determining Face-Validity for a Set of Preventable Drug-Related Morbidity Indicators Developed for Primary Healthcare in South Africa

Authors: D. Velayadum, P. Sthandiwe , N. Maharaj, T. Munien, S. Ndamase, G. Zulu, S. Xulu, F. Oosthuizen

Abstract:

Introduction and aims of the study: It is the responsibility of the pharmacist to manage drug-related problems in order to ensure the greatest benefit to the patient. In order to prevent drug-related morbidity, pharmacists should be aware of medicines that may contribute to certain drug-related problems due to their pharmacological action. In an attempt to assist healthcare practitioners to prevent drug-related morbidity (PDRM), indicators for prevention have been designed. There are currently no indicators available for primary health care in developing countries like South Africa, where the majority of the population access primary health care. There is, therefore, a need to develop such indicators, specifically with the aim of assisting healthcare practitioners in primary health care. Methods: A literature study was conducted to compile a comprehensive list of PDRM indicators as developed internationally using the search engines Google Scholar and PubMed. MESH term used to retrieve suitable articles was 'preventable drug-related morbidity indicators'. The comprehensive list of PDRM indicators obtained from the literature study was further evaluated for face validity. Face validity was done in duplicate by 2 sets of independent researchers to ensure 1) no duplication of indicators when compiling a single list, 2) inclusion of only medication available in primary healthcare, and 3) inclusion of medication currently available in South Africa. Results: The list of indicators, compiled from PDRM indicators in the USA, UK, Portugal, Australia, India, and Canada contained 324 PDRM. 184 of these indicators were found to be duplicates, and the duplications were omitted, leaving a final list of 140. The 140 PDRM indicators were evaluated for face-validity, and 97 were accepted as relevant to primary health care in South Africa. 43 indicators did not comply with the criteria and were omitted from the final list. Conclusion: This study is a first step in compiling a list of PDRM indicators for South Africa. It is important to take cognizance to the fact the health systems differ vastly internationally, and it is, therefore, important to develop country-specific indicators.

Keywords: drug-related morbidity, primary healthcare, South Africa, developing countries

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1843 Creating a Multilevel ESL Learning Community for Adults

Authors: Gloria Chen

Abstract:

When offering conventional level-appropriate ESL classes for adults is not feasible, a multilevel adult ESL class can be formed to benefit those who need to learn English for daily function. This paper examines the rationale, the process, the contents, and the outcomes of a multilevel ESL class for adults. The action research discusses a variety of assessments, lesson plans, teaching strategies that facilitate lifelong language learning. In small towns where adult ESL learners are only a handful, often advanced students and inexperienced students have to be placed in one class. Such class might not be viewed as desirable, but with on-going assessments, careful lesson plans, and purposeful strategies, a multilevel ESL class for adults can overcome the obstacles and help learners to reach a higher level of English proficiency. This research explores some hand-on strategies, such as group rotating, cooperative learning, and modifying textbook contents for practical purpose, and evaluate their effectiveness. The data collected in this research include Needs Assessment (beginning of class term), Mid-term Self-Assessment (5 months into class term), End-of-term Student Reflection (10 months into class), and End-of-term Assessment from the Instructor (10 months into class). A descriptive analysis of the data explains the practice of this particular learning community, and reveal the areas for improvement and enrichment. This research answers the following questions: (1) How do the assessments positively help both learners and instructors? (2) How do the learning strategies prepare students to become independent, life-long English learners? (3) How do materials, grouping, and class schedule enhance the learning? The result of the research contributes to the field of teaching and learning in language, not limited in English, by (a) examining strategies of conducting a multilevel adult class, (b) involving adult language learners with various backgrounds and learning styles for reflection and feedback, and (c) improving teaching and learning strategies upon research methods and results. One unique feature of this research is how students can work together with the instructor to form a learning community, seeking and exploring resources available to them, to become lifelong language learners.

Keywords: adult language learning, assessment, multilevel, teaching strategies

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1842 Rate of Force Development, Net Impulse and Modified Reactive Strength as Predictors of Volleyball Spike Jump Height among Young Elite Players

Authors: Javad Sarvestan, Zdenek Svoboda

Abstract:

Force-time (F-T) curvature characteristics are globally referenced as the main indicators of athletic jump performance. Nevertheless, to the best of authors’ knowledge, no investigation tried to deeply study the relationship between F-T curve variables and real-game jump performance among elite volleyball players. To this end, this study was designated to investigate the association between F-T curve variables, including movement timings, force, velocity, power, rate of force development (RFD), modified reactive strength index (RSImod), and net impulse with spike jump height during real-game circumstances. Twelve young elite volleyball players performed 3 countermovement jump (CMJ) and 3 spike jump in real-game circumstances with 1-minute rest intervals to prevent fatigue. Shapiro-Wilk statistical test illustrated the normality of data distribution, and Pearson’s product correlation test portrayed a significant correlation between CMJ height and peak RFD (0.85), average RFD (r=0.81), RSImod (r=0.88) and concentric net impulse (r=0.98), and also significant correlation between spike jump height and peak RFD (0.73), average RFD (r=0.80), RSImod (r=0.62) and concentric net impulse (r=0.71). Multiple regression analysis also reported that these factors have a strong contribution in predicting of CMJ (98%) and spike jump (77%) heights. Outcomes of this study confirm that the RFD, concentric net impulse, and RSImod values could precisely monitor and track the volleyball attackers’ explosive strength, muscular stretch-shortening cycle function efficiency, and ultimate spike jump height. To this effect, volleyball coaches and trainers are advised to have an in-depth focus on their athletes’ progression or the impacts of strength trainings by observing and chasing the F-T curve variables such as RFD, net impulse, and RSImod.

Keywords: net impulse, reactive strength index, rate of force development, stretch-shortening cycle

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1841 Design of Large Parallel Underground Openings in Himalayas: A Case Study of Desilting Chambers for Punatsangchhu-I, Bhutan

Authors: Kanupreiya, Rajani Sharma

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Construction of a single underground structure is itself a challenging task, and it becomes more critical in tectonically active young mountains such as the Himalayas which are highly anisotropic. The Himalayan geology mostly comprises of incompetent and sheared rock mass in addition to fold/faults, rock burst, and water ingress. Underground tunnels form the most essential and important structure in run-of-river hydroelectric projects. Punatsangchhu I hydroelectric project (PHEP-I), Bhutan (1200 MW) is a run-of-river scheme which has four parallel underground desilting chambers. The Punatsangchhu River carries a large quantity of silt load during monsoon season. Desilting chambers were provided to remove the silt particles of size greater than and equal to 0.2 mm with 90% efficiency, thereby minimizing the rate of damage to turbines. These chambers are 330 m long, 18 m wide at the center and 23.87 m high, with a 5.87 m hopper portion. The geology of desilting chambers was known from an exploratory drift which exposed low dipping foliation joint and six joint sets. The RMR and Q value in this reach varied from 40 to 60 and 1 to 6 respectively. This paper describes different rock engineering principles undertaken for safe excavation and rock support of the moderately jointed, blocky and thinly foliated biotite gneiss. For the design of rock support system of desilting chambers, empirical and numerical analysis was adopted. Finite element analysis was carried out for cavern design and finalization of pillar width using Phase2. Phase2 is a powerful tool for simulation of stage-wise excavation with simultaneous provision of support system. As the geology of the region had 7 sets of joints, in addition to FEM based approach, safety factors for potentially unstable wedges were checked using UnWedge. The final support recommendations were based on continuous face mapping, numerical modelling, empirical calculations, and practical experiences.

Keywords: dam siltation, Himalayan geology, hydropower, rock support, numerical modelling

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1840 A Profile of Out-of-Hospital Cardiac Arrest in ‘Amang’ Rodriguez Memorial Medical Center: A Prospective Cohort Study

Authors: Donna Erika E. De Jesus

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Introduction: Cardiac arrest occurs when abrupt cessation of cardiac function results in loss of effective circulation and complete cardiovascular collapse. For every minute of cardiac arrest without early intervention (cardiopulmonary resuscitation [CPR], defibrillation), chances of survival drop by 7-10%. It is crucial that CPR be initiated within 4-6 minutes to avoid brain death. Most out-of-hospital cardiac arrests (OHCA) occur in a residential setting where access to trained personnel and equipment is not readily available, resulting in poor victim outcomes. Methods: This is a descriptive study done from August to November 2021 using a prospective cohort design. Participants of the study include adult patients aged 18 years and above brought to the emergency room who suffered from out-of-hospital cardiac arrest. Out of the total 102 cases of OHCA, 63 participants were included in the study. Descriptive statistics were used to summarize the demographic and clinical characteristics of the patients. Results: 43 were male patients, comprising the majority at 73.02%. Hypertension was identified as the top co-morbidity, followed by diabetes mellitus, heart failure, and chronic kidney disease (CKD). Medical causes of arrest were identified in 96.83% of the cases. 90.48% of cardiac arrests occurred at home. Only 26 patients (41.27%) received pre-hospital intervention prior to ER arrival, which comprised only hands-only CPR. Twenty-three of which were performed by individuals with background knowledge of CPR. 60.32% were brought via self-conduction, the remainder by ambulances, which were noted to have no available equipment necessary to provide proper resuscitation. The average travel time from dispatch to ER arrival is 20 minutes. Conclusion: Overall survival of OHCA in our local setting remains dismal, as a return of spontaneous circulation was not achieved in any of the patients. The small number of patients having pre-hospital CPR indicates the need for emphasis on training and community education.

Keywords: out-of-hospital cardiac arrest, cardiopulmonary resuscitation, basic life support, emergency medical services

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1839 Building a Blockchain-based Internet of Things

Authors: Rob van den Dam

Abstract:

Today’s Internet of Things (IoT) comprises more than a billion intelligent devices, connected via wired/wireless communications. The expected proliferation of hundreds of billions more places us at the threshold of a transformation sweeping across the communications industry. Yet, we found that the IoT architecture and solutions that currently work for billions of devices won’t necessarily scale to tomorrow’s hundreds of billions of devices because of high cost, lack of privacy, not future-proof, lack of functional value and broken business models. As the IoT scales exponentially, decentralized networks have the potential to reduce infrastructure and maintenance costs to manufacturers. Decentralization also promises increased robustness by removing single points of failure that could exist in traditional centralized networks. By shifting the power in the network from the center to the edges, devices gain greater autonomy and can become points of transactions and economic value creation for owners and users. To validate the underlying technology vision, IBM jointly developed with Samsung Electronics the autonomous decentralized peer-to- peer proof-of-concept (PoC). The primary objective of this PoC was to establish a foundation on which to demonstrate several capabilities that are fundamental to building a decentralized IoT. Though many commercial systems in the future will exist as hybrid centralized-decentralized models, the PoC demonstrated a fully distributed proof. The PoC (a) validated the future vision for decentralized systems to extensively augment today’s centralized solutions, (b) demonstrated foundational IoT tasks without the use of centralized control, (c) proved that empowered devices can engage autonomously in marketplace transactions. The PoC opens the door for the communications and electronics industry to further explore the challenges and opportunities of potential hybrid models that can address the complexity and variety of requirements posed by the internet that continues to scale. Contents: (a) The new approach for an IoT that will be secure and scalable, (b) The three foundational technologies that are key for the future IoT, (c) The related business models and user experiences, (d) How such an IoT will create an 'Economy of Things', (e) The role of users, devices, and industries in the IoT future, (f) The winners in the IoT economy.

Keywords: IoT, internet, wired, wireless

Procedia PDF Downloads 314
1838 Revealing Single Crystal Quality by Insight Diffraction Imaging Technique

Authors: Thu Nhi Tran Caliste

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X-ray Bragg diffraction imaging (“topography”)entered into practical use when Lang designed an “easy” technical setup to characterise the defects / distortions in the high perfection crystals produced for the microelectronics industry. The use of this technique extended to all kind of high quality crystals, and deposited layers, and a series of publications explained, starting from the dynamical theory of diffraction, the contrast of the images of the defects. A quantitative version of “monochromatic topography” known as“Rocking Curve Imaging” (RCI) was implemented, by using synchrotron light and taking advantage of the dramatic improvement of the 2D-detectors and computerised image processing. The rough data is constituted by a number (~300) of images recorded along the diffraction (“rocking”) curve. If the quality of the crystal is such that a one-to-onerelation between a pixel of the detector and a voxel within the crystal can be established (this approximation is very well fulfilled if the local mosaic spread of the voxel is < 1 mradian), a software we developped provides, from the each rocking curve recorded on each of the pixels of the detector, not only the “voxel” integrated intensity (the only data provided by the previous techniques) but also its “mosaic spread” (FWHM) and peak position. We will show, based on many examples, that this new data, never recorded before, open the field to a highly enhanced characterization of the crystal and deposited layers. These examples include the characterization of dislocations and twins occurring during silicon growth, various growth features in Al203, GaNand CdTe (where the diffraction displays the Borrmannanomalous absorption, which leads to a new type of images), and the characterisation of the defects within deposited layers, or their effect on the substrate. We could also observe (due to the very high sensitivity of the setup installed on BM05, which allows revealing these faint effects) that, when dealing with very perfect crystals, the Kato’s interference fringes predicted by dynamical theory are also associated with very small modifications of the local FWHM and peak position (of the order of the µradian). This rather unexpected (at least for us) result appears to be in keeping with preliminary dynamical theory calculations.

Keywords: rocking curve imaging, X-ray diffraction, defect, distortion

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