Search results for: inverse problem in tomography
6004 A Radiographic Superimposition in Orthognathic Surgery of Class III Skeletal Malocclusion
Authors: Albert Suryaprawira
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Patients requiring correction of severe Class III skeletal discrepancy historically has been among the most challenging treatments for orthodontists. Correction of an aesthetic and functional problem is crucially important. This is a case report of an adult male aged 18 years who complained of difficulty in chewing and speaking. Patient has a prominent profile with mandibular excess. The pre-treatment cephalometric radiograph was taken to analyse the skeletal problem and to measure the amount of bone movement and the prediction soft tissue response. The panoramic radiograph was also taken to analyse bone quality, bone abnormality, third molar impaction, etc. Before the surgery, the pre-surgical cephalometric radiograph was taken to re-evaluate the plan and to settle the final amount of bone cut. After the surgery, the post-surgical cephalometric radiograph was taken to confirm the result with the plan. The superimposition between those radiographs was performed to analyse the outcome. It includes the superimposition of the cranial base, maxilla, and mandible. Superimposition is important to describe the amount of hard and soft tissue movement. It is also important to predict the possibility of relapse after the surgery. The patient needs to understand all the surgical plan, outcome and relapse prevention. The surgery included mandibular set back by bilateral sagittal split osteotomies. Although the discrepancy was severe using this combination of treatment and the use of radiographic superimposition, an aesthetically pleasing and stable result was achieved.Keywords: cephalometric, mandibular set back, orthognathic, superimposition
Procedia PDF Downloads 2606003 Saltwater Intrusion Studies in the Cai River in the Khanh Hoa Province, Vietnam
Authors: B. Van Kessel, P. T. Kockelkorn, T. R. Speelman, T. C. Wierikx, C. Mai Van, T. A. Bogaard
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Saltwater intrusion is a common problem in estuaries around the world, as it could hinder the freshwater supply of coastal zones. This problem is likely to grow due to climate change and sea-level rise. The influence of these factors on the saltwater intrusion was investigated for the Cai River in the Khanh Hoa province in Vietnam. In addition, the Cai River has high seasonal fluctuations in discharge, leading to increased saltwater intrusion during the dry season. Sea level rise, river discharge changes, river mouth widening and a proposed saltwater intrusion prevention dam can have influences on the saltwater intrusion but have not been quantified for the Cai River estuary. This research used both an analytical and numerical model to investigate the effect of the aforementioned factors. The analytical model was based on a model proposed by Savenije and was calibrated using limited in situ data. The numerical model was a 3D hydrodynamic model made using the Delft3D4 software. The analytical model and numerical model agreed with in situ data, mostly for tidally average data. Both models indicated a roughly similar dependence on discharge, also agreeing that this parameter had the most severe influence on the modeled saltwater intrusion. Especially for discharges below 10 m/s3, the saltwater was predicted to reach further than 10 km. In the models, both sea-level rise and river widening mainly resulted in salinity increments up to 3 kg/m3 in the middle part of the river. The predicted sea-level rise in 2070 was simulated to lead to an increase of 0.5 km in saltwater intrusion length. Furthermore, the effect of the saltwater intrusion dam seemed significant in the model used, but only for the highest position of the gate.Keywords: Cai River, hydraulic models, river discharge, saltwater intrusion, tidal barriers
Procedia PDF Downloads 1176002 Towards Modern Approaches of Intelligence Measurement for Clinical and Educational Practices
Authors: Alena Kulikova, Tatjana Kanonire
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Intelligence research is one of the oldest fields of psychology. Many factors have made a research on intelligence, defined as reasoning and problem solving [1, 2], a very acute and urgent problem. Thus, it has been repeatedly shown that intelligence is a predictor of academic, professional, and social achievement in adulthood (for example, [3]); Moreover, intelligence predicts these achievements better than any other trait or ability [4]. The individual level, a comprehensive assessment of intelligence is a necessary criterion for the diagnosis of various mental conditions. For example, it is a necessary condition for psychological, medical and pedagogical commissions when deciding on educational needs and the most appropriate educational programs for school children. Assessment of intelligence is crucial in clinical psychodiagnostic and needs high-quality intelligence measurement tools. Therefore, it is not surprising that the development of intelligence tests is an essential part of psychological science and practice. Many modern intelligence tests have a long history and have been used for decades, for example, the Stanford-Binet test or the Wechsler test. However, the vast majority of these tests are based on the classic linear test structure, in which all respondents receive all tasks (see, for example, a critical review by [5]). This understanding of the testing procedure is a legacy of the pre-computer era, in which blank testing was the only diagnostic procedure available [6] and has some significant limitations that affect the reliability of the data obtained [7] and increased time costs. Another problem with measuring IQ is that classical line-structured tests do not fully allow to measure respondent's intellectual progress [8], which is undoubtedly a critical limitation. Advances in modern psychometrics allow for avoiding the limitations of existing tools. However, as in any rapidly developing industry, at the moment, psychometrics does not offer ready-made and straightforward solutions and requires additional research. In our presentation we would like to discuss the strengths and weaknesses of the current approaches to intelligence measurement and highlight “points of growth” for creating a test in accordance with modern psychometrics. Whether it is possible to create the instrument that will use all achievements of modern psychometric and remain valid and practically oriented. What would be the possible limitations for such an instrument? The theoretical framework and study design to create and validate the original Russian comprehensive computer test for measuring the intellectual development in school-age children will be presented.Keywords: Intelligence, psychometrics, psychological measurement, computerized adaptive testing, multistage testing
Procedia PDF Downloads 826001 Tsunami Wave Height and Flow Velocity Calculations Based on Density Measurements of Boulders: Case Studies from Anegada and Pakarang Cape
Authors: Zakiul Fuady, Michaela Spiske
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Inundation events, such as storms and tsunamis can leave onshore sedimentary evidence like sand deposits or large boulders. These deposits store indirect information on the related inundation parameters (e.g., flow velocity, flow depth, wave height). One tool to reveal these parameters are inverse models that use the physical characteristics of the deposits to refer to the magnitude of inundation. This study used boulders of the 2004 Indian Ocean Tsunami from Thailand (Pakarang Cape) and form a historical tsunami event that inundated the outer British Virgin Islands (Anegada). For the largest boulder found in Pakarang Cape with a volume of 26.48 m³ the required tsunami wave height is 0.44 m and storm wave height are 1.75 m (for a bulk density of 1.74 g/cm³. In Pakarang Cape the highest tsunami wave height is 0.45 m and storm wave height are 1.8 m for transporting a 20.07 m³ boulder. On Anegada, the largest boulder with a diameter of 2.7 m is the asingle coral head (species Diploria sp.) with a bulk density of 1.61 g/cm³, and requires a minimum tsunami wave height of 0.31 m and storm wave height of 1.25 m. The highest required tsunami wave height on Anegada is 2.12 m for a boulder with a bulk density of 2.46 g/cm³ (volume 0.0819 m³) and the highest storm wave height is 5.48 m (volume 0.216 m³) from the same bulk density and the coral type is limestone. Generally, the higher the bulk density, volume, and weight of the boulders, the higher the minimum tsunami and storm wave heights required to initiate transport. It requires 4.05 m/s flow velocity by Nott’s equation (2003) and 3.57 m/s by Nandasena et al. (2011) to transport the largest boulder in Pakarang Cape, whereas on Anegada, it requires 3.41 m/s to transport a boulder with diameter 2.7 m for both equations. Thus, boulder equations need to be handled with caution because they make many assumptions and simplifications. Second, the physical boulder parameters, such as density and volume need to be determined carefully to minimize any errors.Keywords: tsunami wave height, storm wave height, flow velocity, boulders, Anegada, Pakarang Cape
Procedia PDF Downloads 2436000 Neural Network Models for Actual Cost and Actual Duration Estimation in Construction Projects: Findings from Greece
Authors: Panagiotis Karadimos, Leonidas Anthopoulos
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Predicting the actual cost and duration in construction projects concern a continuous and existing problem for the construction sector. This paper addresses this problem with modern methods and data available from past public construction projects. 39 bridge projects, constructed in Greece, with a similar type of available data were examined. Considering each project’s attributes with the actual cost and the actual duration, correlation analysis is performed and the most appropriate predictive project variables are defined. Additionally, the most efficient subgroup of variables is selected with the use of the WEKA application, through its attribute selection function. The selected variables are used as input neurons for neural network models through correlation analysis. For constructing neural network models, the application FANN Tool is used. The optimum neural network model, for predicting the actual cost, produced a mean squared error with a value of 3.84886e-05 and it was based on the budgeted cost and the quantity of deck concrete. The optimum neural network model, for predicting the actual duration, produced a mean squared error with a value of 5.89463e-05 and it also was based on the budgeted cost and the amount of deck concrete.Keywords: actual cost and duration, attribute selection, bridge construction, neural networks, predicting models, FANN TOOL, WEKA
Procedia PDF Downloads 1375999 The Impact of Mother Tongue Interference on Students' Performance in English Language in Bauchi State
Authors: Mairo Musa Galadima
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This paper examines the impact of Mother tongue interference on students’ performance in English Language in Bauchi State. It is observed that the students of Bauchi district share the same problem with Hausa native speakers of Kano dialect which is the standard form. It is observed that there are some phonemes which are present in English but absent in Hausa so the Hausa speakers of Bauchi district also replace these sounds with similar ones present in Hausa. Students in Bauchi district fail English language because they transfer features of their mother tongue (MT) into English. The data is obtained through unobtrusive observation of the English speech of about fifty Hausa native speakers of Bauchi district which is similar to Kano dialect from Abubakar Tatari Ali Polytechnic, Bauchi since only those who have had some good background of secondary education are used because uneducated Nigeria English of whatever geographical location is more likely to be unintelligible as cockney or uneducated African-American English. For instance /Ə:/ is absent in Hausa so the speakers find it difficult to distinguish between such pairs of words as /bƏ:d / and /bΛst/, /fa:st/ and /fƏ:st / hence /a:/ is generally used wherever /Ə:/ is present regardless of the spelling, that is why words like ‘work’, ‘first’ and ‘person’ all have / a:/. In Hausa most speakers use /P/ in place of, or in alternation with /f/, e.g. ‘few’ is pronounced as ‘pew’, or ‘pen’, as ‘fen’, /b/ for /v/, /s/ for /z/ and /z/ for /ᵹ/. Also the word vision/visn/ is pronounced as /vidzn/. Therefore, there is confusion in spellings and pronunciation of words. One solution out of the problem is having constant practice with a qualified consistent staff and making use of standard textbooks in the learning process.Keywords: English, failure, mother tongue, interference, students
Procedia PDF Downloads 2255998 An Assessment of Bathymetric Changes in the Lower Usuma Reservoir, Abuja, Nigera
Authors: Rayleigh Dada Abu, Halilu Ahmad Shaba
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Siltation is a serious problem that affects public water supply infrastructures such as dams and reservoirs. It is a major problem which threatens the performance and sustainability of dams and reservoirs. It reduces the dam capacity for flood control, potable water supply, changes water stage, reduces water quality and recreational benefits. The focus of this study is the Lower Usuma reservoir. At completion the reservoir had a gross storage capacity of 100 × 106 m3 (100 million cubic metres), a maximum operational level of 587.440 m a.s.l., with a maximum depth of 49 m and a catchment area of 241 km2 at dam site with a daily designed production capacity of 10,000 cubic metres per hour. The reservoir is 1,300 m long and feeds the treatment plant mainly by gravity. The reservoir became operational in 1986 and no survey has been conducted to determine its current storage capacity and rate of siltation. Hydrographic survey of the reservoir by integrated acoustic echo-sounding technique was conducted in November 2012 to determine the level and rate of siltation. The result obtained shows that the reservoir has lost 12.0 meters depth to siltation in 26 years of its operation; indicating 24.5% loss in installed storage capacity. The present bathymetric survey provides baseline information for future work on siltation depth and annual rates of storage capacity loss for the Lower Usuma reservoir.Keywords: sedimentation, lower Usuma reservoir, acoustic echo sounder, bathymetric survey
Procedia PDF Downloads 5195997 Rainfall Estimation over Northern Tunisia by Combining Meteosat Second Generation Cloud Top Temperature and Tropical Rainfall Measuring Mission Microwave Imager Rain Rates
Authors: Saoussen Dhib, Chris M. Mannaerts, Zoubeida Bargaoui, Ben H. P. Maathuis, Petra Budde
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In this study, a new method to delineate rain areas in northern Tunisia is presented. The proposed approach is based on the blending of the geostationary Meteosat Second Generation (MSG) infrared channel (IR) with the low-earth orbiting passive Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI). To blend this two products, we need to apply two main steps. Firstly, we have to identify the rainy pixels. This step is achieved based on a classification using MSG channel IR 10.8 and the water vapor WV 0.62, applying a threshold on the temperature difference of less than 11 Kelvin which is an approximation of the clouds that have a high likelihood of precipitation. The second step consists on fitting the relation between IR cloud top temperature with the TMI rain rates. The correlation coefficient of these two variables has a negative tendency, meaning that with decreasing temperature there is an increase in rainfall intensity. The fitting equation will be applied for the whole day of MSG 15 minutes interval images which will be summed. To validate this combined product, daily extreme rainfall events occurred during the period 2007-2009 were selected, using a threshold criterion for large rainfall depth (> 50 mm/day) occurring at least at one rainfall station. Inverse distance interpolation method was applied to generate rainfall maps for the drier summer season (from May to October) and the wet winter season (from November to April). The evaluation results of the estimated rainfall combining MSG and TMI was very encouraging where all the events were detected rainy and the correlation coefficients were much better than previous evaluated products over the study area such as MSGMPE and PERSIANN products. The combined product showed a better performance during wet season. We notice also an overestimation of the maximal estimated rain for many events.Keywords: combination, extreme, rainfall, TMI-MSG, Tunisia
Procedia PDF Downloads 1785996 Feedback Matrix Approach for Relativistic Runaway Electron Avalanches Dynamics in Complex Electric Field Structures
Authors: Egor Stadnichuk
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Relativistic runaway electron avalanches (RREA) are a widely accepted source of thunderstorm gamma-radiation. In regions with huge electric field strength, RREA can multiply via relativistic feedback. The relativistic feedback is caused both by positron production and by runaway electron bremsstrahlung gamma-rays reversal. In complex multilayer thunderstorm electric field structures, an additional reactor feedback mechanism appears due to gamma-ray exchange between separate strong electric field regions with different electric field directions. The study of this reactor mechanism in conjunction with the relativistic feedback with Monte Carlo simulations or by direct solution of the kinetic Boltzmann equation requires a significant amount of computational time. In this work, a theoretical approach to study feedback mechanisms in RREA physics is developed. It is based on the matrix of feedback operators construction. With the feedback matrix, the problem of the dynamics of avalanches in complex electric structures is reduced to the problem of finding eigenvectors and eigenvalues. A method of matrix elements calculation is proposed. The proposed concept was used to study the dynamics of RREAs in multilayer thunderclouds.Keywords: terrestrial Gamma-ray flashes, thunderstorm ground enhancement, relativistic runaway electron avalanches, gamma-rays, high-energy atmospheric physics, TGF, TGE, thunderstorm, relativistic feedback, reactor feedback, reactor model
Procedia PDF Downloads 1775995 Extension of the Simplified Theory of Plastic Zones for Analyzing Elastic Shakedown in a Multi-Dimensional Load Domain
Authors: Bastian Vollrath, Hartwig Hubel
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In case of over-elastic and cyclic loading, strain may accumulate due to a ratcheting mechanism until the state of shakedown is possibly achieved. Load history dependent numerical investigations by a step-by-step analysis are rather costly in terms of engineering time and numerical effort. In the case of multi-parameter loading, where various independent loadings affect the final state of shakedown, the computational effort becomes an additional challenge. Therefore, direct methods like the Simplified Theory of Plastic Zones (STPZ) are developed to solve the problem with a few linear elastic analyses. Post-shakedown quantities such as strain ranges and cyclic accumulated strains are calculated approximately by disregarding the load history. The STPZ is based on estimates of a transformed internal variable, which can be used to perform modified elastic analyses, where the elastic material parameters are modified, and initial strains are applied as modified loading, resulting in residual stresses and strains. The STPZ already turned out to work well with respect to cyclic loading between two states of loading. Usually, few linear elastic analyses are sufficient to obtain a good approximation to the post-shakedown quantities. In a multi-dimensional load domain, the approximation of the transformed internal variable transforms from a plane problem into a hyperspace problem, where time-consuming approximation methods need to be applied. Therefore, a solution restricted to structures with four stress components was developed to estimate the transformed internal variable by means of three-dimensional vector algebra. This paper presents the extension to cyclic multi-parameter loading so that an unlimited number of load cases can be taken into account. The theoretical basis and basic presumptions of the Simplified Theory of Plastic Zones are outlined for the case of elastic shakedown. The extension of the method to many load cases is explained, and a workflow of the procedure is illustrated. An example, adopting the FE-implementation of the method into ANSYS and considering multilinear hardening is given which highlights the advantages of the method compared to incremental, step-by-step analysis.Keywords: cyclic loading, direct method, elastic shakedown, multi-parameter loading, STPZ
Procedia PDF Downloads 1655994 Materials and Techniques of Anonymous Egyptian Polychrome Cartonnage Mummy Mask: A Multiple Analytical Study
Authors: Hanaa A. Al-Gaoudi, Hassan Ebeid
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The research investigates the materials and processes used in the manufacturing of an Egyptian polychrome cartonnage mummy mask with the aim of dating this object and establishing trade patterns of certain materials that were used and available at the time of ancient Egypt. This anonymous-source object was held in the basement storage of the Egyptian Museum in Cairo (EMC) and has never been on display. Furthermore, there is no information available regarding its owner, provenance, date, and even the time of its possession by the museum. Moreover, the object is in a very poor condition where almost two-thirds of the mask was bent and has never received any previous conservation treatment. This research has utilized well-established multi-analytical methods to identify the considerable diversity of materials that have been used in the manufacturing of this object. These methods include Computed Tomography Scan (CT scan) to acquire detailed pictures of the inside physical structure and condition of the bended layers. Dino-Lite portable digital microscope, scanning electron microscopy with energy dispersive X-ray spectrometer (SEM-EDX), and the non-invasive imaging technique of multispectral imaging (MSI) to obtain information about the physical characteristics and condition of the painted layers and to examine the microstructure of the materials. Portable XRF Spectrometer (PXRF) and X-Ray powder diffraction (XRD) to identify mineral phases and the bulk element composition in the gilded layer, ground, and pigments; Fourier-transform infrared (FTIR) to identify organic compounds and their molecular characterization; accelerator mass spectrometry (AMS 14C) to date the object. Preliminary results suggest that there are no human remains inside the object, and the textile support is linen fibres with tabby weave 1/1 and these fibres are in a very bad condition. Several pigments have been identified, such as Egyptian blue, Magnetite, Egyptian green frit, Hematite, Calcite, and Cinnabar; moreover, the gilded layers are pure gold and the binding media in the pigments is Arabic gum and animal glue in the textile support layer.Keywords: analytical methods, Egyptian museum, mummy mask, pigments, textile
Procedia PDF Downloads 1275993 System Identification of Building Structures with Continuous Modeling
Authors: Ruichong Zhang, Fadi Sawaged, Lotfi Gargab
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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
Procedia PDF Downloads 2365992 Rare Diagnosis in Emergency Room: Moyamoya Disease
Authors: Ecem Deniz Kırkpantur, Ozge Ecmel Onur, Tuba Cimilli Ozturk, Ebru Unal Akoglu
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Moyamoya disease is a unique chronic progressive cerebrovascular disease characterized by bilateral stenosis or occlusion of the arteries around the circle of Willis with prominent arterial collateral circulation. The occurrence of Moyamoya disease is related to immune, genetic and other factors. There is no curative treatment for Moyamoya disease. Secondary prevention for patients with symptomatic Moyamoya disease is largely centered on surgical revascularization techniques. We present here a 62-year old male presented with headache and vision loss for 2 days. He was previously diagnosed with hypertension and glaucoma. On physical examination, left eye movements were restricted medially, both eyes were hyperemic and their movements were painful. Other neurological and physical examination were normal. His vital signs and laboratory results were within normal limits. Computed tomography (CT) showed dilated vascular structures around both lateral ventricles and atherosclerotic changes inside the walls of internal carotid artery (ICA). Magnetic resonance imaging (MRI) and angiography (MRA) revealed dilated venous vascular structures around lateral ventricles and hyper-intense gliosis in periventricular white matter. Ischemic gliosis around the lateral ventricles were present in the Digital Subtracted Angiography (DSA). After the neurology, ophthalmology and neurosurgery consultation, the patient was diagnosed with Moyamoya disease, pulse steroid therapy was started for vision loss, and super-selective DSA was planned for further investigation. Moyamoya disease is a rare condition, but it can be an important cause of stroke in both children and adults. It generally affects anterior circulation, but posterior cerebral circulation may also be affected, as well. In the differential diagnosis of acute vision loss, occipital stroke related to Moyamoya disease should be considered. Direct and indirect surgical revascularization surgeries may be used to effectively revascularize affected brain areas, and have been shown to reduce risk of stroke.Keywords: headache, Moyamoya disease, stroke, visual loss
Procedia PDF Downloads 2695991 In situ Ortho-Quinone Methide Reactions for Construction of Flavonoids with Fused Ring Systems
Authors: Vidia A. Nuraini, Eugene M. H. Yee, Mohan Bhadbhade, David StC. Black, Naresh Kumar
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Flavonoids are naturally occurring compounds that have been shown to exhibit a wide range of biological properties including anticancer and anti-inflammatory activities. However, flavonoids suffer from low bioavailability, which limits their overall utility for therapeutic applications. One of the methods to overcome this limitation is through structural modification of natural flavonoids. In this study, flavanone, isoflavanone, and isoflavene, were structurally modified through the introduction of additional fused-ring systems via ortho-quinone methide intermediates (o-QMs). These intermediates can readily undergo a [4+2] cycloaddition through an inverse-electron-demand Diels–Alder reaction with electron-rich dienophiles. A regioselective Mannich reaction using bis-(N,N-dimethylamino)methane was employed to generate the o-QM precursors of flavanone, isoflavanone, and isoflavene. The o-QM intermediates were subsequently generated in situ through thermal elimination of the dimethylamine functionality and reacted with a variety of dienophiles to produce novel flavonoids with fused-ring systems. A total of 21 novel flavonoid analogs were successfully synthesized. The X-ray crystal structure of cycloaddition adducts, particularly those derived from 3,4-dihydro-2H-pyran and p-methoxystyrene revealed a special case of enantiomeric disorder, where two enantiomers in equal amounts superpose with one another, with the exception for atoms that have opposite configuration. The anticancer properties of fused-ring systems derived from isoflavene were evaluated against the neuroblastoma SKN-BE(2)C, the triple negative breast cancer MDA-MB-231, and the glioblastoma U87 cancer cell lines. One of these cycloaddition adducts had displayed improved anti-proliferative activity against MDA-MB-231 and U87 cancer cell lines as compared to the parent compound. Further anticancer and anti-inflammatory activities of the flavanone and isoflavanone analogs are currently being investigated.Keywords: Diels-Alder reaction, flavonoids, Mannich reaction, ortho-quinone methide.
Procedia PDF Downloads 2555990 Unveiling the Mystery: Median Arcuate Ligament Syndrome in a Middle-Aged Female Presenting with Abdominal Pain
Authors: Thaer Khaleel Swaid, Maryam Al Ahmad, Ishtiaq Ahmad
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47-year-old female, known to have a liver cyst and hemangiomas, presented to the gastroenterology clinic for chronic moderate postprandial epigastric pain, which is aggravated by food, leaning forward and relieved on lying flat. The pain was associated with nausea, vomiting, heartburn and excessive burping. She opened her bowel daily, having well-formed stools without blood or mucus. The patient denied NSAID intake, smoking or alcohol. On physical examination during the episode of pain abdomen revealed a soft, lax abdomen and mild tenderness in the epigastric region without organomegaly. Bowel sounds were audible. Her routine hematological and biochemical parameters were within normal, including CBC, Celiac serology, Lipase, Metabolic profile and H pylori stool antigen. The patient underwent an Ultrasound of the abdomen which showed multiple liver cysts, hemangioma, normal GB and biliary tree. Based on the clinical picture and to narrow our differential diagnosis, an ultrasound Doppler for the abdomen was ordered, and it showed celiac artery peak systolic velocity in expiration is 270cm/s, suggestive of median arcuate ligament syndrome. She Had computerized tomography abdomen done and showed a Narrowing of the celiac artery at the origin, likely secondary to low insertion of the median arcuate ligament. Furthermore, Gastroscopy and, later on colonoscopy were done, which was unremarkable. A laparoscopic decompression of the celiac trunk was indicated, for which the patient was referred to vascular surgery. This case confirms that Median Arcuate Ligament syndrome is an unusual diagnosis and is always challenging. Usually, patients undergo extensive workups before a final diagnosis is achieved. Our case highlights the challenge of diagnosing MALS since this entity is rare. It is a good choice to perform abdominal ultrasound with Doppler imaging on a patient with symptoms such as postprandial angina.Keywords: Unveiling the Mystery, MALS, rare entity, Rare vascular phenomenon
Procedia PDF Downloads 225989 Non-Local Behavior of a Mixed-Mode Crack in a Functionally Graded Piezoelectric Medium
Authors: Nidhal Jamia, Sami El-Borgi
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In this paper, the problem of a mixed-Mode crack embedded in an infinite medium made of a functionally graded piezoelectric material (FGPM) with crack surfaces subjected to electro-mechanical loadings is investigated. Eringen’s non-local theory of elasticity is adopted to formulate the governing electro-elastic equations. The properties of the piezoelectric material are assumed to vary exponentially along a perpendicular plane to the crack. Using Fourier transform, three integral equations are obtained in which the unknown variables are the jumps of mechanical displacements and electric potentials across the crack surfaces. To solve the integral equations, the unknowns are directly expanded as a series of Jacobi polynomials, and the resulting equations solved using the Schmidt method. In contrast to the classical solutions based on the local theory, it is found that no mechanical stress and electric displacement singularities are present at the crack tips when nonlocal theory is employed to investigate the problem. A direct benefit is the ability to use the calculated maximum stress as a fracture criterion. The primary objective of this study is to investigate the effects of crack length, material gradient parameter describing FGPMs, and lattice parameter on the mechanical stress and electric displacement field near crack tips.Keywords: functionally graded piezoelectric material (FGPM), mixed-mode crack, non-local theory, Schmidt method
Procedia PDF Downloads 3105988 Investigation on Behaviour of Reinforced Concrete Beam-Column Joints Retrofitted with CFRP
Authors: Ehsan Mohseni
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The aim of this thesis is to provide numerical analyses of reinforced concrete beams-column joints with/without CFRP (Carbon Fiber Reinforced Polymer) in order to achieve a better understanding of the behaviour of strengthened beamcolumn joints. A comprehensive literature survey prior to this study revealed that published studies are limited to a handful only; the results are inconclusive and some are even contradictory. Therefore in order to improve on this situation, following that review, a numerical study was designed and performed as presented in this thesis. For the numerical study, dimensions, end supports, and characteristics of the beam and column models were the same as those chosen in an experimental investigation performed previously where ten beamcolumn joint were tested tofailure. Finite element analysis is a useful tool in cases where analytical methods are not capable of solving the problem due to the complexities associated with the problem. The cyclic behaviour of FRP strengthened reinforced concrete beam-columns joints is such a case. Interaction of steel (longitudinal and stirrups), concrete and FRP, yielding of steel bars and stirrups, cracking of concrete, the redistribution of stresses as some elements unload due to crushing or yielding and the confinement of concrete due to the presence of FRP are some of the issues that introduce the complexities into the problem.Numerical solutions, however, can provide further in formation about the behaviour in lieu of the costly experiments or complex closed form solutions. This thesis presents the results of a numerical study on beam-column joints subjected to cyclic loads that are strengthened with CFRP wraps or strrips in a variety of configurations. The analyses are performed by Abaqus finite element program and are calibrated with the experiments. A range of issues in beam-column joints including the cracking load, the ultimate load, lateral load-displacement curves of joints, are investigated.The numerical results for different configurations of strengthening are compared. Finally, the computed numerical results are compared with those obtained from experiments. the cracking load, the ultimate load, lateral load-displacement curves obtained from numerical analysis for all joints were in very good agreement with the corresponding experimental ones.The results obtained from the numerical analysis in most cases implies that this method is conservative and therefore can be used in design applications with confidence.Keywords: numerical analysis, strengthening, CFRP, reinforced concrete joints
Procedia PDF Downloads 3515987 Analytical Studies on Subgrade Soil Using Jute Geotextiles
Authors: A. Vinod Kumar, G. Sunny Deol, Rakesh Kumar, B. Chandra
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Application of fiber reinforcement in road construction is gaining some interest in enhancing soil strength. In this paper, the natural Geotextile material obtained from gunny bags was used due to vast local availability material. Construction of flexible pavement on weaker soil such as clay soils are a significant problem in construction as well as in design due to its expansive characteristics. Jute Geotextile (JGT) was used on a foundation layer of flexible pavement on rural roads. This problem will be conquered by increasing the subgrade strength by decreasing sub-base layer thickness by improving their overall pavement strength characteristics which ultimately reduces the cost of construction and leads to economically design. The California Bearing Ratio (CBR), unconfined compressive strength (UCS) and triaxial laboratory tests were conducted on two different soil samples CI and MI. Weaker soil is reinforced with JGT, JGT+Bitumen; JGT+polythene sheet was varied with heights while performing the laboratory tests. Subgrade strength evaluation was investigated by conducting soak CBR test in the laboratory for clayey and silt soils. Laboratory results reveal that reinforced soak CBR value of clayey soil (CI) observed was 10.35%, and silty soil (MI) was 15.6%. This study intends to develop new technique for reinforcing weaker soil with JGT varying parameters for the need of low volume flexible pavements. It was observed that the performance of JGT is inferior when used with bitumen and polyethylene sheets.Keywords: CBR, Jute geotextile, low volume road, weaker soil
Procedia PDF Downloads 4325986 Prevalence and Determinants of Depression among Orphans and Vulnerable Children in Child Care Homes in Nepal
Authors: Kumari Bandana Bhatt, Navin Bhatt
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Background: Orphans and vulnerable children (OVC) are high risk of physical, mental, sexual and emotional abuse and face social stigma and discrimination which significantly increase the risk of mental and behavioral disorders such as anxiety, depression or emotional problems even they stay in well run child care homes. The objective of this study was to estimate the prevalence of depression and determine the determinants among OVC in child care homes in Nepal. Methods: An institutional-based analytical cross-sectional study was conducted in twenty orphanages of five districts of Nepal. Six hundred two children were recruited into the study. After the informed consent form obtaining, the guardian and assent were interviewed by a semi-structured questionnaire and Beck Depression Inventory-II (BDI-II). Logistic regression was used for detecting the association between variables at the significant level of =0.05. Results: The study revealed that 33.20% of OVC had depression. Among them 66.80% of children experienced minimal depression, 17.40% had mild depression, 11.30% had moderate depression 4.50% had severe depression. Sex, alcohol drinking, congenital problem, social support and bully were the main variables associated with depression among OVC of the child care homes in Nepal. Conclusion: Prevalence of depression was high among the orphans and vulnerable children living in child care homes especially among the female children in Nepal. Therefore, early identification and instituting of preventive measures of depression are essential to reduce this problem in this special group of children living in child care homes.Keywords: Mental health, Depression, Orphans and vulnerable children, child care homes
Procedia PDF Downloads 1535985 Mixed Mode Fracture Analyses Using Finite Element Method of Edge Cracked Heavy Spinning Annulus Pulley
Authors: Bijit Kalita, K. V. N. Surendra
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Rotating disk is one of the most indispensable parts of a rotating machine. Rotating disk has found many applications in the diverging field of science and technology. In this paper, we have taken into consideration the problem of a heavy spinning disk mounted on a rotor system acted upon by boundary traction. Finite element modelling is used at various loading condition to determine the mixed mode stress intensity factors. The effect of combined shear and normal traction on the boundary is incorporated in the analysis under the action of gravity. The variation near the crack tip is characterized in terms of the stress intensity factor (SIF) with an aim to find the SIF for a wide range of parameters. The results of the finite element analyses carried out on the compressed disk of a belt pulley arrangement using fracture mechanics concepts are shown. A total of hundred cases of the problem are solved for each of the variations in loading arc parameter and crack orientation using finite element models of the disc under compression. All models were prepared and analyzed for the uncracked disk, disk with a single crack at different orientation emanating from shaft hole as well as for a disc with pair of cracks emerging from the same center hole. Curves are plotted for various loading conditions. Finally, crack propagation paths are determined using kink angle concepts.Keywords: crack-tip deformations, static loading, stress concentration, stress intensity factor
Procedia PDF Downloads 1485984 Computed Tomography Myocardial Perfusion on a Patient with Hypertrophic Cardiomyopathy
Authors: Jitendra Pratap, Daphne Prybyszcuk, Luke Elliott, Arnold Ng
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Introduction: Coronary CT angiography is a non-invasive imaging technique for the assessment of coronary artery disease and has high sensitivity and negative predictive value. However, the correlation between the degree of CT coronary stenosis and the significance of hemodynamic obstruction is poor. The assessment of myocardial perfusion has mostly been undertaken by Nuclear Medicine (SPECT), but it is now possible to perform stress myocardial CT perfusion (CTP) scans quickly and effectively using CT scanners with high temporal resolution. Myocardial CTP is in many ways similar to neuro perfusion imaging technique, where radiopaque iodinated contrast is injected intravenously, transits the pulmonary and cardiac structures, and then perfuses through the coronary arteries into the myocardium. On the Siemens Force CT scanner, a myocardial perfusion scan is performed using a dynamic axial acquisition, where the scanner shuffles in and out every 1-3 seconds (heart rate dependent) to be able to cover the heart in the z plane. This is usually performed over 38 seconds. Report: A CT myocardial perfusion scan can be utilised to complement the findings of a CT Coronary Angiogram. Implementing a CT Myocardial Perfusion study as part of a routine CT Coronary Angiogram procedure provides a ‘One Stop Shop’ for diagnosis of coronary artery disease. This case study demonstrates that although the CT Coronary Angiogram was within normal limits, the perfusion scan provided additional, clinically significant information in regards to the haemodynamics within the myocardium of a patient with Hypertrophic Obstructive Cardio Myopathy (HOCM). This negated the need for further diagnostics studies such as cardiac ECHO or Nuclear Medicine Stress tests. Conclusion: CT coronary angiography with adenosine stress myocardial CTP was utilised in this case to specifically exclude coronary artery disease in conjunction with accessing perfusion within the hypertrophic myocardium. Adenosine stress myocardial CTP demonstrated the reduced myocardial blood flow within the hypertrophic myocardium, but the coronary arteries did not show any obstructive disease. A CT coronary angiogram scan protocol that incorporates myocardial perfusion can provide diagnostic information on the haemodynamic significance of any coronary artery stenosis and has the potential to be a “One Stop Shop” for cardiac imaging.Keywords: CT, cardiac, myocardium, perfusion
Procedia PDF Downloads 1365983 Using Thinking Blocks to Encourage the Use of Higher Order Thinking Skills among Students When Solving Problems on Fractions
Authors: Abdul Halim Abdullah, Nur Liyana Zainal Abidin, Mahani Mokhtar
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Problem-solving is an activity which can encourage students to use Higher Order Thinking Skills (HOTS). Learning fractions can be challenging for students since empirical evidence shows that students experience difficulties in solving the fraction problems. However, visual methods can help students to overcome the difficulties since the methods help students to make meaningful visual representations and link abstract concepts in Mathematics. Therefore, the purpose of this study was to investigate whether there were any changes in students’ HOTS at the four highest levels when learning the fractions by using Thinking Blocks. 54 students participated in a quasi-experiment using pre-tests and post-tests. Students were divided into two groups. The experimental group (n=32) received a treatment to improve the students’ HOTS and the other group acted as the control group (n=22) which used a traditional method. Data were analysed by using Mann-Whitney test. The results indicated that during post-test, students who used Thinking Blocks showed significant improvement in their HOTS level (p=0.000). In addition, the results of post-test also showed that the students’ performance improved significantly at the four highest levels of HOTS; namely, application (p=0.001), analyse (p=0.000), evaluate (p=0.000), and create (p=0.000). Therefore, it can be concluded that Thinking Blocks can effectively encourage students to use the four highest levels of HOTS which consequently enable them to solve fractions problems successfully.Keywords: Thinking Blocks, Higher Order Thinking Skills (HOTS), fractions, problem solving
Procedia PDF Downloads 2735982 A Comprehensive Evaluation of Supervised Machine Learning for the Phase Identification Problem
Authors: Brandon Foggo, Nanpeng Yu
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Power distribution circuits undergo frequent network topology changes that are often left undocumented. As a result, the documentation of a circuit’s connectivity becomes inaccurate with time. The lack of reliable circuit connectivity information is one of the biggest obstacles to model, monitor, and control modern distribution systems. To enhance the reliability and efficiency of electric power distribution systems, the circuit’s connectivity information must be updated periodically. This paper focuses on one critical component of a distribution circuit’s topology - the secondary transformer to phase association. This topology component describes the set of phase lines that feed power to a given secondary transformer (and therefore a given group of power consumers). Finding the documentation of this component is call Phase Identification, and is typically performed with physical measurements. These measurements can take time lengths on the order of several months, but with supervised learning, the time length can be reduced significantly. This paper compares several such methods applied to Phase Identification for a large range of real distribution circuits, describes a method of training data selection, describes preprocessing steps unique to the Phase Identification problem, and ultimately describes a method which obtains high accuracy (> 96% in most cases, > 92% in the worst case) using only 5% of the measurements typically used for Phase Identification.Keywords: distribution network, machine learning, network topology, phase identification, smart grid
Procedia PDF Downloads 3045981 The Impact of Bilateral Investment Treaties on Health-Related Intellectual Property Rights in the Agreement on Trade-Related Aspects of Intellectual Property Rights in the Kingdom of Saudi Arabia and Australia
Authors: Abdulrahman Fahim M. Alsulami
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This paper is dedicated to a detailed investigation of the interaction between the agreement on trade-related aspects of intellectual property rights (TRIPS) and bilateral investment treaties (BITs) in the regulation of health-related intellectual property rights in Australia and the Kingdom of Saudi Arabia. The chosen research object is complex and requires a thorough examination of a set of factors influencing the problem under investigation. At the moment, to the author’s best knowledge’ there is no academic research that would conceptualize and critically compare the regulation of health-related intellectual property rights in these two countries. While there is a substantial amount of information in the literature on certain aspects of the problem, the existing knowledge about certain aspects of the health-related regulatory frameworks in Australia and Saudi Arabia barely explains in detail the specifics of the ways in which the TRIPS agreement interacts with (BITs) in the regulation of health-related intellectual property rights. Therefore, this paper will address an evident research gap by studying an intriguing yet under-researched problem. The paper comprises five subsections. The first subsection provides an overview of the investment climate in Saudi Arabia and Australia with an emphasis on the health care industry. It will cover political, economic, and social factors influencing the investment climate in these countries, the systems of intellectual property rights protection, recent patterns relevant to the investment climate’s development, and key characteristics of the investment climate in the health care industry. The second subsection analyses BITs in Saudi Arabia and Australia in light of the countries’ responsibilities under the TRIPS Agreement. The third subsection provides a critical examination of the interaction between the TRIPS Agreement and BITs in Saudi Arabia on the basis of data collected and analyzed in previous subsections. It will investigate key discrepancies concerning the regulation of health-related intellectual property rights in Saudi Arabia and Australia from the position of BITs’ interaction with the TRIPS Agreement and explore the existing procedures for clarifying priorities between them in regulating health-related intellectual property rights. The fourth subsection of the paper provides recommendations concerning the transformation of BITS into a TRIPS+ dimension in regulating health-related intellectual property rights in Saudi Arabia and Australia. The final subsection provides a summary of differences between the Australian and Saudi BITs from the perspective of the regulation of health-related intellectual property rights under the TRIPS agreement and bilateral investment treaties.Keywords: Australia, bilateral investment treaties, IP law, public health sector, Saudi Arabia
Procedia PDF Downloads 1485980 Review on Crew Scheduling of Bus Transit: A Case Study in Kolkata
Authors: Sapan Tiwari, Namrata Ghosh
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In urban mass transit, crew scheduling always plays a significant role. It deals with the formulation of work timetables for its staff so that an organization can meet the demand for its products or services. The efficient schedules of a specified timetable have an enormous impact on staff demand. It implies that an urban mass transit company's financial outcomes are strongly associated with planning operations in the region. The research aims to demonstrate the state of the crew scheduling studies and its practical implementation in mass transit businesses in metropolitan areas. First, there is a short overview of past studies in the field. Subsequently, the restrictions and problems with crew scheduling and some models, which have been developed to solve the related issues with their mathematical formulation, are defined. The comments are completed by a description of the solution opportunities provided by computer-aided scheduling program systems for operational use and exposures from urban mass transit organizations. Furthermore, Bus scheduling is performed using the Hungarian technique of problem-solving tasks and mathematical modeling. Afterward, the crew scheduling problem, which consists of developing duties using predefined tasks with set start and end times and places, is resolved. Each duty has to comply with a set line of work. The objective is to minimize a mixture of fixed expenses (number of duties) and varying costs. After the optimization of cost, the outcome of the research is that the same frequency can be provided with fewer buses and less workforce.Keywords: crew scheduling, duty, optimization of cost, urban mass transit
Procedia PDF Downloads 1545979 A Concept of Rational Water Management at Local Utilities: The Use of RO for Water Supply and Wastewater Treatment/Reuse
Authors: N. Matveev, A. Pervov
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Local utilities often face problems of local industrial wastes, storm water disposal due to existing strict regulations. For many local industries, the problem of wastewater treatment and discharge into surface reservoirs can’t be solved through the use of conventional biological treatment techniques. Current discharge standards require very strict removal of a number of impurities such as ammonia, nitrates, phosphate, etc. To reach this level of removal, expensive reagents and sorbents are used. The modern concept of rational water resources management requires the development of new efficient techniques that provide wastewater treatment and reuse. As RO membranes simultaneously reject all dissolved impurities such as BOD, TDS, ammonia, phosphates etc., they become very attractive for the direct treatment of wastewater without biological stage. To treat wastewater, specially designed membrane "open channel" modules are used that do not possess "dead areas" that cause fouling or require pretreatment. A solution to RO concentrate disposal problem is presented that consists of reducing of initial wastewater volume by 100 times. Concentrate is withdrawn from membrane unit as sludge moisture. The efficient use of membrane RO techniques is connected with a salt balance in water system. Thus, to provide high ecological efficiency of developed techniques, all components of water supply and wastewater discharge systems should be accounted for.Keywords: reverse osmosis, stormwater treatment, open-channel module, wastewater reuse
Procedia PDF Downloads 3215978 Resolving a Piping Vibration Problem by Installing Viscous Damper Supports
Authors: Carlos Herrera Sierralta, Husain M. Muslim, Meshal T. Alsaiari, Daniel Fischer
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Preventing piping fatigue flow induced vibration in the Oil & Gas sector demands not only the constant development of engineering design methodologies based on available software packages, but also special piping support technologies for designing safe and reliable piping systems. The vast majority of piping vibration problems in the Oil & Gas industry are provoked by the process flow characteristics which are basically intrinsically related to the fluid properties, the type of service and its different operational scenarios. In general, the corrective actions recommended for flow induced vibration in piping systems can be grouped in two major areas: those which affect the excitation mechanisms typically associated to process variables, and those which affect the response mechanism of the pipework per se, and the pipework associated steel support structure. Where possible the first option is to try to solve the flow induced problem from the excitation mechanism perspective. However, in producing facilities the approach of changing process parameters might not always be convenient as it could lead to reduction of production rates or it may require the shutdown of the system in order to perform the required piping modification. That impediment might lead to a second option, which is to modify the response of the piping system to excitation generated by the type of process flow. In principle, the action of shifting the natural frequency of the system well above the frequency inherent to the process always favours the elimination, or considerably reduces, the level of vibration experienced by the piping system. Tightening up the clearances at the supports (ideally zero gap), and adding new static supports at the system, are typical ways of increasing the natural frequency of the piping system. However, only stiffening the piping system may not be sufficient to resolve the vibration problem, and in some cases, it might not be feasible to implement it at all, as the available piping layout could create limitations on adding supports due to thermal expansion/contraction requirements. In these cases, utilization of viscous damper supports could be recommended as these devices can allow relatively large quasi-static movement of piping while providing sufficient capabilities of dissipating the vibration. Therefore, when correctly selected and installed, viscous damper supports can provide a significant effect on the response of the piping system over a wide range of frequencies. Viscous dampers cannot be used to support sustained, static loads. This paper shows over a real case example, a methodology which allows to determine the selection of the viscous damper supports via a dynamic analysis model. By implementing this methodology, it was possible to resolve the piping vibration problem throughout redesigning adequately the existing static piping supports and by adding new viscous dampers supports. This was conducted on-stream at the oil crude pipeline in question without the necessity of reducing the production of the plant. Concluding that the application of the methodology of this paper can be applied to solve similar cases in a straightforward manner.Keywords: dynamic analysis, flow induced vibration, piping supports, turbulent flow, slug flow, viscous damper
Procedia PDF Downloads 1475977 Influence of Strike-Slip Faulting in the Tectonic Evolution of North-Eastern Tunisia
Authors: Aymen Arfaoui, Abdelkader Soumaya, Ali Kadri, Noureddine Ben Ayed
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The major contractional events characterized by strike-slip faulting, folding, and thrusting occurred in the Eocene, Late Miocene, and Quaternary along with the NE Tunisian domain between Bou Kornine-Ressas- Msella and Cap Bon Peninsula. During the Plio-Quaternary, the Grombalia and Mornag grabens show a maximum of collapse in parallelism with the NNW-SSE SHmax direction and developed as 3rd order extensive regions within a regional compressional regime. Using available tectonic and geophysical data supplemented by new fault-kinematic observations, we show that Cenozoic deformations are dominated by first order N-S faults reactivation, this sinistral wrench system is responsible for the formation of strike-slip duplexes, thrusts, folds, and grabens. Based on our new structural interpretation, the major faults of N-S Axis, Bou Kornine-Ressas-Messella (MRB), and Hammamet-Korbous (HK) form an N-S first order restraining stepover within a left-lateral strike-slip duplex. The N-S master MRB fault is dominated by contractional imbricate fans, while the parallel HK fault is characterized by a trailing of extensional imbricate fans. The Eocene and Miocene compression phases in the study area caused sinistral strike-slip reactivation of pre-existing N-S faults, reverse reactivation of NE-SW trending faults, and normal-oblique reactivation of NW-SE faults, creating a NE-SW to N-S trending system of east-verging folds and overlaps. Seismic tomography images reveal a key role for the lithospheric subvertical tear or STEP fault (Slab Transfer Edge Propagator) evidenced below this region on the development of the MRB and the HK relay zone. The presence of extensive syntectonic Pliocene sequences above this crustal scale fault may be the result of a recent lithospheric vertical motion of this STEP fault due to the rollback and lateral migration of the Calabrian slab eastward.Keywords: Tunisia, strike-slip fault, contractional duplex, tectonic stress, restraining stepover, STEP fault
Procedia PDF Downloads 1365976 Mitigation of Interference in Satellite Communications Systems via a Cross-Layer Coding Technique
Authors: Mario A. Blanco, Nicholas Burkhardt
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An important problem in satellite communication systems which operate in the Ka and EHF frequency bands consists of the overall degradation in link performance of mobile terminals due to various types of degradations in the link/channel, such as fading, blockage of the link to the satellite (especially in urban environments), intentional as well as other types of interference, etc. In this paper, we focus primarily on the interference problem, and we develop a very efficient and cost-effective solution based on the use of fountain codes. We first introduce a satellite communications (SATCOM) terminal uplink interference channel model that is classically used against communication systems that use spread-spectrum waveforms. We then consider the use of fountain codes, with focus on Raptor codes, as our main mitigation technique to combat the degradation in link/receiver performance due to the interference signal. The performance of the receiver is obtained in terms of average probability of bit and message error rate as a function of bit energy-to-noise density ratio, Eb/N0, and other parameters of interest, via a combination of analysis and computer simulations, and we show that the use of fountain codes is extremely effective in overcoming the effects of intentional interference on the performance of the receiver and associated communication links. We then show this technique can be extended to mitigate other types of SATCOM channel degradations, such as those caused by channel fading, shadowing, and hard-blockage of the uplink signal.Keywords: SATCOM, interference mitigation, fountain codes, turbo codes, cross-layer
Procedia PDF Downloads 3665975 The Need for Innovation Management in the Context of Integrated Management Systems
Authors: Adela Mariana Vadastreanu, Adrian Bot, Andreea Maier, Dorin Maier
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This paper approaches the need for innovation management in the context of an existing integrated management system implemented in an organization. The road to success for companies in today’s economic environment is more demanding than ever and the capacity of adapting to the rapid changes is compensatory in order to resist on the market. The managers struggle, daily, with increasingly complex problems, caused by fierce competition in the market but also from the rising demands of customers. Innovation seems to be the solution for these problems. During the last decade almost all companies have been certificated according to various management systems, like quality management system, environmental management system, health and safety management system and others; furthermore many companies have implemented an integrated management system, by integrating two or more management systems. The problem rising today is how to integrate innovation in this integrated management systems. The challenge of the problem is that the development of an innovation management system is in the early phase. In this paper we have studied the possibility of integrating some of the innovation request in an existing management system, we have identify the innovation performance request and we proposed some recommendations regarding innovation management and its implementation as a part of an integrated management system. This paper lies down the bases for developing an model of integration management systems that include innovation as a main part of it. Organizations are becoming more aware of the importance of Integrated Management Systems (IMS). Integrating two or more management systems into an integrated management system can have much advantages.This paper examines various models of management systems integration in accordance with professional references ISO 9001, ISO 18001 and OHSAS 18001, highlighting strengths and weaknesses, creating a basis for future development of integrated management systems, and their involvement in various other processes within the organization, such as innovation management. The more and more demanding economic context emphasizes the awareness of the importance of innovation for organizations. This paper highlights the importance of the innovation for an organization and also gives some practical solution in order to improve the overall success of the business through a better approach of innovation. Various standards have been developed in order to certificate organizations that they respect the requirements. Applying an integrated standards model is shown to be a more effective way then applying the standards independently. The problem that arises is that in order to adopt the integrated version of standards there have to be made some changes at the organizational level. Every change that needs to be done has an effect on its activity, and in this sense the paper tries to deal with the changes needed for adopting an integrated management system and if those changes have an influence over the performance. After the analysis of the results, we can conclude that in order to improve the performance a necessary step is the implementation of innovation in the existing integrated management system.Keywords: innovation, integrated management systems, innovation management, quality
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