Search results for: abnormal mode
1817 Fracture Behaviour of Functionally Graded Materials Using Graded Finite Elements
Authors: Mohamad Molavi Nojumi, Xiaodong Wang
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In this research fracture behaviour of linear elastic isotropic functionally graded materials (FGMs) are investigated using modified finite element method (FEM). FGMs are advantageous because they enhance the bonding strength of two incompatible materials, and reduce the residual stress and thermal stress. Ceramic/metals are a main type of FGMs. Ceramic materials are brittle. So, there is high possibility of crack existence during fabrication or in-service loading. In addition, damage analysis is necessary for a safe and efficient design. FEM is a strong numerical tool for analyzing complicated problems. Thus, FEM is used to investigate the fracture behaviour of FGMs. Here an accurate 9-node biquadratic quadrilateral graded element is proposed in which the influence of the variation of material properties is considered at the element level. The stiffness matrix of graded elements is obtained using the principle of minimum potential energy. The implementation of graded elements prevents the forced sudden jump of material properties in traditional finite elements for modelling FGMs. Numerical results are verified with existing solutions. Different numerical simulations are carried out to model stationary crack problems in nonhomogeneous plates. In these simulations, material variation is supposed to happen in directions perpendicular and parallel to the crack line. Two special linear and exponential functions have been utilized to model the material gradient as they are mostly discussed in literature. Also, various sizes of the crack length are considered. A major difference in the fracture behaviour of FGMs and homogeneous materials is related to the break of material symmetry. For example, when the material gradation direction is normal to the crack line, even under applying the mode I loading there exists coupled modes I and II of fracture which originates from the induced shear in the model. Therefore, the necessity of the proper modelling of the material variation should be considered in capturing the fracture behaviour of FGMs specially, when the material gradient index is high. Fracture properties such as mode I and mode II stress intensity factors (SIFs), energy release rates, and field variables near the crack tip are investigated and compared with results obtained using conventional homogeneous elements. It is revealed that graded elements provide higher accuracy with less effort in comparison with conventional homogeneous elements.Keywords: finite element, fracture mechanics, functionally graded materials, graded element
Procedia PDF Downloads 1751816 Effect of Different Muscle Contraction Mode on the Expression of Myostatin, IGF-1, and PGC-1 Alpha Family Members in Human Vastus Lateralis Muscle
Authors: Pejman Taghibeikzadehbadr
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Muscle contraction stimulates a transient change of myogenic factors, partly related to the mode of contractions. Here, we assessed the response of Insulin-like growth factor 1Ea (IGF-1Ea), Insulin-like growth factor 1Eb (IGF-1Eb), Insulin-like growth factor 1Ec (IGF-1Ec), Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α-1), Peroxisome proliferator-activated receptor gamma coactivator 4-alpha (PGC1α-4), and myostatin to the eccentric Vs the concentric contraction in human skeletal muscle. Ten healthy males were performed an acute eccentric and concentric exercise bout (n = 5 per group). For each contraction type, participants performed 12 sets of 10 repetitions knee extension by the dominant leg. Baseline and post-exercise muscle biopsy were taken 4 weeks before and immediately after experimental sessions from Vastus Lateralis muscle. Genes expression was measured by real-time PCR technique. There was a significant increase in PGC1α-1, PGC1α-4, IGF-1Ea and, IGF-1Eb mRNA after concentric contraction (p ≤ 0.05), while the PGC1α-4 and IGF-1Ec significantly increased after eccentric contraction (p ≤ 0.05). It is intriguing to highlight that; no significant differences between groups were evident for changes in any variables following exercise bouts (p ≥ 0.05). Our results found that concentric and eccentric contractions presented different responses in PGC1α-1, IGF-1Ea, IGF-1Eb, and IGF-1Ec mRNA. However, a similar significant increase in mRNA content was observed in PGC1α-4. Further, no apparent differences could be found between the response of genes to eccentric and concentric contraction.Keywords: eccentric contraction, concentric contraction, gene expression, PGC-1 alpha, IGF-1 Myostatin
Procedia PDF Downloads 1601815 Detection of New Attacks on Ubiquitous Services in Cloud Computing and Countermeasures
Authors: L. Sellami, D. Idoughi, P. F. Tiako
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Cloud computing provides infrastructure to the enterprise through the Internet allowing access to cloud services at anytime and anywhere. This pervasive aspect of the services, the distributed nature of data and the wide use of information make cloud computing vulnerable to intrusions that violate the security of the cloud. This requires the use of security mechanisms to detect malicious behavior in network communications and hosts such as intrusion detection systems (IDS). In this article, we focus on the detection of intrusion into the cloud sing IDSs. We base ourselves on client authentication in the computing cloud. This technique allows to detect the abnormal use of ubiquitous service and prevents the intrusion of cloud computing. This is an approach based on client authentication data. Our IDS provides intrusion detection inside and outside cloud computing network. It is a double protection approach: The security user node and the global security cloud computing.Keywords: cloud computing, intrusion detection system, privacy, trust
Procedia PDF Downloads 3251814 Evaluation of Liquid Fermentation Strategies to Obtain a Biofertilizer Based on Rhizobium sp.
Authors: Andres Diaz Garcia, Ana Maria Ceballos Rojas, Duvan Albeiro Millan Montano
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This paper describes the initial technological development stages in the area of liquid fermentation required to reach the quantities of biomass of the biofertilizer microorganism Rhizobium sp. strain B02, for the application of the unitary stages downstream at laboratory scale. In the first stage, the adjustment and standardization of the fermentation process in conventional batch mode were carried out. In the second stage, various fed-batch and continuous fermentation strategies were evaluated in 10L-bioreactor in order to optimize the yields in concentration (Colony Forming Units/ml•h) and biomass (g/l•h), to make feasible the application of unit operations downstream of process. The growth kinetics, the evolution of dissolved oxygen and the pH profile generated in each of the strategies were monitored and used to make sequential adjustments. Once the fermentation was finished, the final concentration and viability of the obtained biomass were determined and performance parameters were calculated with the purpose of select the optimal operating conditions that significantly improved the baseline results. Under the conditions adjusted and standardized in batch mode, concentrations of 6.67E9 CFU/ml were reached after 27 hours of fermentation and a subsequent noticeable decrease was observed associated with a basification of the culture medium. By applying fed-batch and continuous strategies, significant increases in yields were achieved, but with similar concentration levels, which involved the design of several production scenarios based on the availability of equipment usage time and volume of required batch.Keywords: biofertilizer, liquid fermentation, Rhizobium sp., standardization of processes
Procedia PDF Downloads 1771813 Influence of Argon Gas Concentration in N2-Ar Plasma for the Nitridation of Si in Abnormal Glow Discharge
Authors: K. Abbas, R. Ahmad, I. A. Khan, S. Saleem, U. Ikhlaq
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Nitriding of p-type Si samples by pulsed DC glow discharge is carried out for different Ar concentrations (30% to 90%) in nitrogen-argon plasma whereas the other parameters like pressure (2 mbar), treatment time (4 hr) and power (175 W) are kept constant. The phase identification, crystal structure, crystallinity, chemical composition, surface morphology and topography of the nitrided layer are studied using X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), optical microscopy (OM), scanning electron microscopy (SEM) and atomic force microscopy (AFM) respectively. The XRD patterns reveal the development of different diffraction planes of Si3N4 confirming the formation of polycrystalline layer. FTIR spectrum confirms the formation of bond between Si and N. Results reveal that addition of Ar into N2 plasma plays an important role to enhance the production of active species which facilitate the nitrogen diffusion.Keywords: crystallinity, glow discharge, nitriding, sputtering
Procedia PDF Downloads 4221812 Flexural Strength of Alkali Resistant Glass Textile Reinforced Concrete Beam with Prestressing
Authors: Jongho Park, Taekyun Kim, Jungbhin You, Sungnam Hong, Sun-Kyu Park
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Due to the aging of bridges, increasing of maintenance costs and decreasing of structural safety is occurred. The steel corrosion of reinforced concrete bridge is the most common problem and this phenomenon is accelerating due to abnormal weather and increasing CO2 concentration due to climate change. To solve these problems, composite members using textile have been studied. A textile reinforced concrete can reduce carbon emissions by reduced concrete and without steel bars, so a lot of structural behavior studies are needed. Therefore, in this study, textile reinforced concrete beam was made and flexural test was performed. Also, the change of flexural strength according to the prestressing was conducted. As a result, flexural strength of TRC with prestressing was increased compared and flexural behavior was shown as reinforced concrete.Keywords: AR-glass, flexural strength, prestressing, textile reinforced concrete
Procedia PDF Downloads 3311811 An Approach Based on Statistics and Multi-Resolution Representation to Classify Mammograms
Authors: Nebi Gedik
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One of the significant and continual public health problems in the world is breast cancer. Early detection is very important to fight the disease, and mammography has been one of the most common and reliable methods to detect the disease in the early stages. However, it is a difficult task, and computer-aided diagnosis (CAD) systems are needed to assist radiologists in providing both accurate and uniform evaluation for mass in mammograms. In this study, a multiresolution statistical method to classify mammograms as normal and abnormal in digitized mammograms is used to construct a CAD system. The mammogram images are represented by wave atom transform, and this representation is made by certain groups of coefficients, independently. The CAD system is designed by calculating some statistical features using each group of coefficients. The classification is performed by using support vector machine (SVM).Keywords: wave atom transform, statistical features, multi-resolution representation, mammogram
Procedia PDF Downloads 2231810 Placenta Parenchymal Dysplasia: When to Depend on Color Doppler and MRI
Authors: Bernard Olumide Ewuoso, Asma Gharaibeh
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Rationale: Placental mesenchymal dysplasia (PMD) resembles molar pregnancy quite a bit. Although there have been documented live births of healthy babies, obtaining an objective diagnosis is crucial to assisting the mother in making an educated decision on what option of management she would like to explore. Prenatal invasive testing is recommended to help obtain an objective diagnosis in cases of abnormal placenta. We present a 23-year-old who, at 14 weeks, had ultrasonographic findings suggestive of placental mesenchymal dysplasia. She was offered prenatal invasive testing but declined and opted for surgical management, with a diagnosis of PMD confirmed on histopathology. There will be occasions such as this when prenatal invasive testing is declined. In these situations, careful consideration can be given to color Doppler and MRI, especially if the patient decides to keep pregnancy.Keywords: placental mesenchymal dysplasisa, molar pregnancy, prenatal invasive testing, Color doppler, MRI
Procedia PDF Downloads 251809 Residential and Care Model for Elderly People Based on “Internet Plus”
Authors: Haoyi Sheng
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China's aging tendency is becoming increasingly severe, which leads to the embarrassing situation of "getting old before getting wealthy". The traditional pension model does not comply with the need of today. Relying on "Internet Plus", it can efficiently integrate information and resources and meet the personalized needs of elderly care. It can reduce the operating cost of community elderly care facilities and lay a technical foundation for providing better services for the elderly. The key for providing help for the elderly in the future is to effectively integrate technology, make good use of technology, and improve the efficiency of elderly care services. The effective integration of traditional home care, community care, intelligent elderly care equipment and medical resources to create the "Internet Plus" community intelligent pension service mode has become the future development trend of aging care. The research method of this paper is to collect literature and conduct theoretical research on community pension firstly. Secondly, the combination of suitable aging design and "Internet Plus" is elaborated through research. Finally, this paper states the current level of intelligent technology in old-age care and looks into the future by understanding multiple levels of "Internet Plus". The development of community intelligent pension mode and content under "Internet Plus" has enormous development potential. In addition to the characteristics and functions of ordinary houses, residential design of endowment housing has higher requirements for comfort and personalization, and the people-oriented is the principle of design.Keywords: ageing tendency, 'Internet Plus', community intelligent elderly care, elderly care service model, technology
Procedia PDF Downloads 1381808 AgriInnoConnect Pro System Using Iot and Firebase Console
Authors: Amit Barde, Dipali Khatave, Vaishali Savale, Atharva Chavan, Sapna Wagaj, Aditya Jilla
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AgriInnoConnect Pro is an advanced agricultural automation system designed to enhance irrigation efficiency and overall farm management through IoT technology. Using MIT App Inventor, Telegram, Arduino IDE, and Firebase Console, it provides a user-friendly interface for farmers. Key hardware includes soil moisture sensors, DHT11 sensors, a 12V motor, a solenoid valve, a stepdown transformer, Smart Fencing, and AC switches. The system operates in automatic and manual modes. In automatic mode, the ESP32 microcontroller monitors soil moisture and autonomously controls irrigation to optimize water usage. In manual mode, users can control the irrigation motor via a mobile app. Telegram bots enable remote operation of the solenoid valve and electric fencing, enhancing farm security. Additionally, the system upgrades conventional devices to smart ones using AC switches, broadening automation capabilities. AgriInnoConnect Pro aims to improve farm productivity and resource management, addressing the critical need for sustainable water conservation and providing a comprehensive solution for modern farm management. The integration of smart technologies in AgriInnoConnect Pro ensures precision farming practices, promoting efficient resource allocation and sustainable agricultural development.Keywords: agricultural automation, IoT, soil moisture sensor, ESP32, MIT app inventor, telegram bot, smart farming, remote control, firebase console
Procedia PDF Downloads 461807 Analysis of the Vibration Behavior of a Small-Scale Wind Turbine Blade under Johannesburg Wind Speed
Authors: Tolulope Babawarun, Harry Ngwangwa
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The wind turbine blade may sustain structural damage from external loads such as high winds or collisions, which could compromise its aerodynamic efficiency. The wind turbine blade vibrates at significant intensities and amplitudes under these conditions. The effect of these vibrations on the dynamic flow field surrounding the blade changes the forces operating on it. The structural dynamic analysis of a small wind turbine blade is considered in this study. It entails creating a finite element model, validating the model, and doing structural analysis on the verified finite element model. The analysis is based on the structural reaction of a small-scale wind turbine blade to various loading sources. Although there are many small-scale off-shore wind turbine systems in use, only preliminary structural analysis is performed during design phases; these systems' performance under various loading conditions as they are encountered in real-world situations has not been properly researched. This will allow us to record the same Equivalent von Mises stress and deformation that the blade underwent. A higher stress contour was found to be more concentrated near the middle span of the blade under the various loading scenarios studied. The highest stress that the blade in this study underwent is within the range of the maximum stress that blade material can withstand. The maximum allowable stress of the blade material is 1,770 MPa. The deformation of the blade was highest at the blade tip. The critical speed of the blade was determined to be 4.3 Rpm with a rotor speed range of 0 to 608 Rpm. The blade's mode form under loading conditions indicates a bending mode, the most prevalent of which is flapwise bending.Keywords: ANSYS, finite element analysis, static loading, dynamic analysis
Procedia PDF Downloads 871806 Insight into the Binding Theme of CA-074Me to Cathepsin B: Molecular Dynamics Simulations and Scaffold Hopping to Identify Potential Analogues as Anti-Neurodegenerative Diseases
Authors: Tivani Phosa Mashamba-Thompson, Mahmoud E. S. Soliman
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To date, the cause of neurodegeneration is not well understood and diseases that stem from neurodegeneration currently have no known cures. Cathepsin B (CB) enzyme is known to be involved in the production of peptide neurotransmitters and toxic peptides in neurodegenerative diseases (NDs). CA-074Me is a membrane-permeable irreversible selective cathepsin B (CB) inhibitor as confirmed by in vivo studies. Due to the lack of the crystal structure, the binding mode of CA-074Me with the human CB at molecular level has not been previously reported. The main aim of this study is to gain an insight into the binding mode of CB CA-074Me to human CB using various computational tools. Herein, molecular dynamics simulations, binding free energy calculations and per-residue energy decomposition analysis were employed to accomplish the aim of the study. Another objective was to identify novel CB inhibitors based on the structure of CA-074Me using fragment based drug design using scaffold hoping drug design approach. Results showed that two of the designed ligands (hit 1 and hit 2) were found to have better binding affinities than the prototype inhibitor, CA-074Me, by ~2-3 kcal/mol. Per-residue energy decomposition showed that amino acid residues Cys29, Gly196, His197 and Val174 contributed the most towards the binding. The Van der Waals binding forces were found to be the major component of the binding interactions. The findings of this study should assist medicinal chemist towards the design of potential irreversible CB inhibitors.Keywords: cathepsin B, scaffold hopping, docking, molecular dynamics, binding-free energy, neurodegerative diseases
Procedia PDF Downloads 3771805 Relationship Between Brain Entropy Patterns Estimated by Resting State fMRI and Child Behaviour
Authors: Sonia Boscenco, Zihan Wang, Euclides José de Mendoça Filho, João Paulo Hoppe, Irina Pokhvisneva, Geoffrey B.C. Hall, Michael J. Meaney, Patricia Pelufo Silveira
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Entropy can be described as a measure of the number of states of a system, and when used in the context of physiological time-based signals, it serves as a measure of complexity. In functional connectivity data, entropy can account for the moment-to-moment variability that is neglected in traditional functional magnetic resonance imaging (fMRI) analyses. While brain fMRI resting state entropy has been associated with some pathological conditions like schizophrenia, no investigations have explored the association between brain entropy measures and individual differences in child behavior in healthy children. We describe a novel exploratory approach to evaluate brain fMRI resting state data in two child cohorts, and MAVAN (N=54, 4.5 years, 48% males) and GUSTO (N = 206, 4.5 years, 48% males) and its associations to child behavior, that can be used in future research in the context of child exposures and long-term health. Following rs-fMRI data pre-processing and Shannon entropy calculation across 32 network regions of interest to acquire 496 unique functional connections, partial correlation coefficient analysis adjusted for sex was performed to identify associations between entropy data and Strengths and Difficulties questionnaire in MAVAN and Child Behavior Checklist domains in GUSTO. Significance was set at p < 0.01, and we found eight significant associations in GUSTO. Negative associations were found between two frontoparietal regions and cerebellar posterior and oppositional defiant problems, (r = -0.212, p = 0.006) and (r = -0.200, p = 0.009). Positive associations were identified between somatic complaints and four default mode connections: salience insula (r = 0.202, p < 0.01), dorsal attention intraparietal sulcus (r = 0.231, p = 0.003), language inferior frontal gyrus (r = 0.207, p = 0.008) and language posterior superior temporal gyrus (r = 0.210, p = 0.008). Positive associations were also found between insula and frontoparietal connection and attention deficit / hyperactivity problems (r = 0.200, p < 0.01), and insula – default mode connection and pervasive developmental problems (r = 0.210, p = 0.007). In MAVAN, ten significant associations were identified. Two positive associations were found = with prosocial scores: the salience prefrontal cortex and dorsal attention connection (r = 0.474, p = 0.005) and the salience supramarginal gyrus and dorsal attention intraparietal sulcus (r = 0.447, p = 0.008). The insula and prefrontal connection were negatively associated with peer problems (r = -0.437, p < 0.01). Conduct problems were negatively associated with six separate connections, the left salience insula and right salience insula (r = -0.449, p = 0.008), left salience insula and right salience supramarginal gyrus (r = -0.512, p = 0.002), the default mode and visual network (r = -0.444, p = 0.009), dorsal attention and language network (r = -0.490, p = 0.003), and default mode and posterior parietal cortex (r = -0.546, p = 0.001). Entropy measures of resting state functional connectivity can be used to identify individual differences in brain function that are correlated with variation in behavioral problems in healthy children. Further studies applying this marker into the context of environmental exposures are warranted.Keywords: child behaviour, functional connectivity, imaging, Shannon entropy
Procedia PDF Downloads 2041804 Characteristics of Plasma Synthetic Jet Actuator in Repetitive Working Mode
Authors: Haohua Zong, Marios Kotsonis
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Plasma synthetic jet actuator (PSJA) is a new concept of zero net mass flow actuator which utilizes pulsed arc/spark discharge to rapidly pressurize gas in a small cavity under constant-volume conditions. The unique combination of high exit jet velocity (>400 m/s) and high actuation frequency (>5 kHz) provides a promising solution for high-speed high-Reynolds-number flow control. This paper focuses on the performance of PSJA in repetitive working mode which is more relevant to future flow control applications. A two-electrodes PSJA (cavity volume: 424 mm3, orifice diameter: 2 mm) together with a capacitive discharge circuit (discharge energy: 50 mJ-110 mJ) is designed to enable repetitive operation. Time-Resolved Particle Imaging Velocimetry (TR-PIV) system working at 10 kHz is exploited to investigate the influence of discharge frequency on performance of PSJA. In total, seven cases are tested, covering a wide range of discharge frequencies (20 Hz-560 Hz). The pertinent flow features (shock wave, vortex ring and jet) remain the same for single shot mode and repetitive working mode. Shock wave is issued prior to jet eruption. Two distinct vortex rings are formed in one cycle. The first one is produced by the starting jet whereas the second one is related with the shock wave reflection in cavity. A sudden pressure rise is induced at the throat inlet by the reflection of primary shock wave, promoting the shedding of second vortex ring. In one cycle, jet exit velocity first increases sharply, then decreases almost linearly. Afterwards, an alternate occurrence of multiple jet stages and refresh stages is observed. By monitoring the dynamic evolution of exit velocity in one cycle, some integral performance parameters of PSJA can be deduced. As frequency increases, the jet intensity in steady phase decreases monotonically. In the investigated frequency range, jet duration time drops from 250 µs to 210 µs and peak jet velocity decreases from 53 m/s to approximately 39 m/s. The jet impulse and the expelled gas mass (0.69 µN∙s and 0.027 mg at 20 Hz) decline by 48% and 40%, respectively. However, the electro-mechanical efficiency of PSJA defined by the ratio of jet mechanical energy to capacitor energy doesn’t show significant difference (o(0.01%)). Fourier transformation of the temporal exit velocity signal indicates two dominant frequencies. One corresponds to the discharge frequency, while the other accounts for the alternation frequency of jet stage and refresh stage in one cycle. The alternation period (300 µs approximately) is independent of discharge frequency, and possibly determined intrinsically by the actuator geometry. A simple analytical model is established to interpret the alternation of jet stage and refresh stage. Results show that the dynamic response of exit velocity to a small-scale disturbance (jump in cavity pressure) can be treated as a second-order under-damping system. Oscillation frequency of the exit velocity, namely alternation frequency, is positively proportional to exit area, but inversely proportional to cavity volume and throat length. Theoretical value of alternation period (305 µs) agrees well with the experimental value.Keywords: plasma, synthetic jet, actuator, frequency effect
Procedia PDF Downloads 2551803 Mode of Action of Surface Bound Antimicrobial Peptides Melimine and Mel4 against Pseudomonas aeruginosa
Authors: Muhammad Yasir, Debarun Dutta, Mark Willcox
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Biomaterial-associated infections are a multi-billion dollar burden globally. Antimicrobial peptide-based coatings may be able to prevent such infections. The aim of this study was to investigate the mechanism of action surface bound peptides (AMPs) against Pseudomonas aeruginosa 6294. Melimine and Mel4 were covalently attached to glass coverslips using azido-benzoic acid. Attachment was confirmed using X-ray photoelectron spectroscopy. P. aeruginosa was allowed to attach to AMP-coated glass for up to 6 hours. The effect of the surface-bound AMPs on bacterial cell membranes was evaluated using the dyes DiSC3-(5), Sytox green, SYTO 9 and propidium iodide with fluorescence microscopy. Release of cytoplasmic materials ATP and DNA/RNA were determined in the surrounding fluid. The amount of cell death was estimated by agar plate counts. The AMPs were successfully covalently bound to the glass as demonstrated by increases in %nitrogen of 3.6% (melimine) and 2.3% (Mel4) compared to controls. Immobilized peptides disrupted the cytoplasmic membrane potential of P. aeruginosa within 10 min. This was followed by the release of ATP after 2 h. Membrane permeabilization started at 3 h of contact with glass coated AMPs. There was a significant number of bacteria (59% for melimine; 36% for Mel-4) with damaged membranes after 4 h of contact. At the 6 h time point, release of DNA occurred with melimine releasing 2 times the amount of DNA/RNA than Mel4 surfaces (p < 0.05). Surface bound AMPs were able to disrupt cell membranes with subsequent release of cytoplasmic materials, and ultimately resulting in bacterial death.Keywords: biomaterials, immobilized antimicrobial peptides, P. aeruginosa, mode of action
Procedia PDF Downloads 1361802 Benefits of High Power Impulse Magnetron Sputtering (HiPIMS) Method for Preparation of Transparent Indium Gallium Zinc Oxide (IGZO) Thin Films
Authors: Pavel Baroch, Jiri Rezek, Michal Prochazka, Tomas Kozak, Jiri Houska
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Transparent semiconducting amorphous IGZO films have attracted great attention due to their excellent electrical properties and possible utilization in thin film transistors or in photovoltaic applications as they show 20-50 times higher mobility than that of amorphous silicon. It is also known that the properties of IGZO films are highly sensitive to process parameters, especially to oxygen partial pressure. In this study we have focused on the comparison of properties of transparent semiconducting amorphous indium gallium zinc oxide (IGZO) thin films prepared by conventional sputtering methods and those prepared by high power impulse magnetron sputtering (HiPIMS) method. Furthermore we tried to optimize electrical and optical properties of the IGZO thin films and to investigate possibility to apply these coatings on thermally sensitive flexible substrates. We employed dc, pulsed dc, mid frequency sine wave and HiPIMS power supplies for magnetron deposition. Magnetrons were equipped with sintered ceramic InGaZnO targets. As oxygen vacancies are considered to be the main source of the carriers in IGZO films, it is expected that with the increase of oxygen partial pressure number of oxygen vacancies decreases which results in the increase of film resistivity. Therefore in all experiments we focused on the effect of oxygen partial pressure, discharge power and pulsed power mode on the electrical, optical and mechanical properties of IGZO thin films and also on the thermal load deposited to the substrate. As expected, we have observed a very fast transition between low- and high-resistivity films depending on oxygen partial pressure when deposition using conventional sputtering methods/power supplies have been utilized. Therefore we established and utilized HiPIMS sputtering system for enlargement of operation window for better control of IGZO thin film properties. It is shown that with this system we are able to effectively eliminate steep transition between low and high resistivity films exhibited by DC mode of sputtering and the electrical resistivity can be effectively controlled in the wide resistivity range of 10-² to 10⁵ Ω.cm. The highest mobility of charge carriers (up to 50 cm2/V.s) was obtained at very low oxygen partial pressures. Utilization of HiPIMS also led to significant decrease in thermal load deposited to the substrate which is beneficial for deposition on the thermally sensitive and flexible polymer substrates. Deposition rate as a function of discharge power and oxygen partial pressure was also systematically investigated and the results from optical, electrical and structure analysis will be discussed in detail. Most important result which we have obtained demonstrates almost linear control of IGZO thin films resistivity with increasing of oxygen partial pressure utilizing HiPIMS mode of sputtering and highly transparent films with low resistivity were prepared already at low pO2. It was also found that utilization of HiPIMS technique resulted in significant improvement of surface smoothness in reactive mode of sputtering (with increasing of oxygen partial pressure).Keywords: charge carrier mobility, HiPIMS, IGZO, resistivity
Procedia PDF Downloads 2991801 Evaluation Treatment of 130 Feline Infectious Peritonitis (FIP) Cats with GS-441524 in Iran
Authors: Manely Ansary Mood, Farzaneh Aziizi, Mahmoud Akbarian
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This investigation included 130 cats diagnosed with FIP (Feb 2021-March 2022) in Iran, 74 with effusive FIP, and 56 with non-effusive FIP. The patients' initial dosage regime consisted of a subcutaneous injection of GS-441524 was 6-15mg/kg-every 24h (based on the wet or ocular and neurologic signs). The minimum treatment period was twelve weeks, extended in animals that still had abnormal lab values, clinical signs, and sonographic findings. The outcomes of the 130 cats that completed the duration of treatment (14 died, 116 cured) were checked and recorded. Clinical, sonographic, and laboratory responses were checked and compared on days 28, 56, and 83 of treatment. 2 of the 116 cured cats relapsed within observation days. At the time of this publication (May 2022), 114 of the studied patients remained healthy. We could conclude that GS-441524 appears to be an effective option for FIP treatment, and also, to the base of our knowledge, this is the first report for group treatment of infected cats of FIP with GS-441524 in Iran.Keywords: FIP, cat, GS-441524, treatment
Procedia PDF Downloads 1191800 Analyzing Music Theory in Different Countries: Compare with Greece and China
Authors: Baoshan Wang
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The present study investigates how music theory has developed across different countries due to their diverse histories, religions, and cultural differences. It is unknown how these various factors may contribute to differences in music theory across countries. Therefore, we examine the differences between China and Greece, which have developed unique music theories over time. Specifically, our analysis looks at musical notation and scales. For example, Tonal music originates from Greece, which harbors quite complex notation and scaling. There exist seven notes in each scale within seven modes of scales. Each mode of the diatonic scale has a unique temperament, two of which are most commonly used in modern music. In contrast, we find that Chinese music has only five notes in its scales. Interestingly, a unique feature of Chinese music theory is that there is no half-step, resulting in a highly divergent and culture-specific sound. Fascinatingly, these differences may arise from the contrasting ways that Western and Eastern musicians perceive music. While Western musicians tend to believe in music “without borders,” Eastern musicians generally embrace differing perspectives. Yet, the vast majority of colleges or music conservatories teach the borderless theory of Western music, which renders the music educational system incomplete. This is critically important because learning music is not simply a profession for musicians. Rather, it is an intermediary to facilitate understanding and appreciation for different countries’ cultures and religions. Education is undoubtedly the optimal mode to promote different countries’ music theory so people across the world can learn more about music and, in turn, each other. Even though Western music theory is predominantly taught, it is crucial we also pursue an understanding of other countries’ music because their unique aspects contribute to the systematic completeness of Music Theory in its entirety.Keywords: culture, development, music theory, music history, religion, western music
Procedia PDF Downloads 951799 Inversion of the Spectral Analysis of Surface Waves Dispersion Curves through the Particle Swarm Optimization Algorithm
Authors: A. Cerrato Casado, C. Guigou, P. Jean
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In this investigation, the particle swarm optimization (PSO) algorithm is used to perform the inversion of the dispersion curves in the spectral analysis of surface waves (SASW) method. This inverse problem usually presents complicated solution spaces with many local minima that make difficult the convergence to the correct solution. PSO is a metaheuristic method that was originally designed to simulate social behavior but has demonstrated powerful capabilities to solve inverse problems with complex space solution and a high number of variables. The dispersion curve of the synthetic soils is constructed by the vertical flexibility coefficient method, which is especially convenient for soils where the stiffness does not increase gradually with depth. The reason is that these types of soil profiles are not normally dispersive since the dominant mode of Rayleigh waves is usually not coincident with the fundamental mode. Multiple synthetic soil profiles have been tested to show the characteristics of the convergence process and assess the accuracy of the final soil profile. In addition, the inversion procedure is applied to multiple real soils and the final profile compared with the available information. The combination of the vertical flexibility coefficient method to obtain the dispersion curve and the PSO algorithm to carry out the inversion process proves to be a robust procedure that is able to provide good solutions for complex soil profiles even with scarce prior information.Keywords: dispersion, inverse problem, particle swarm optimization, SASW, soil profile
Procedia PDF Downloads 1851798 Influence of Iron Content in Carbon Nanotubes on the Intensity of Hyperthermia in the Cancer Treatment
Authors: S. Wiak, L. Szymanski, Z. Kolacinski, G. Raniszewski, L. Pietrzak, Z. Staniszewska
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The term ‘cancer’ is given to a collection of related diseases that may affect any part of the human body. It is a pathological behaviour of cells with the potential to undergo abnormal breakdown in the processes that control cell proliferation, differentiation, and death of particular cells. Although cancer is commonly considered as modern disease, there are beliefs that drastically growing number of new cases can be linked to the extensively prolonged life expectancy and enhanced techniques for cancer diagnosis. Magnetic hyperthermia therapy is a novel approach to cancer treatment, which may greatly contribute to higher efficiency of the therapy. Employing carbon nanotubes as nanocarriers for magnetic particles, it is possible to decrease toxicity and invasiveness of the treatment by surface functionalisation. Despite appearing in recent years, magnetic particle hyperthermia has already become of the highest interest in the scientific and medical environment. The reason why hyperthermia therapy brings so much hope for future treatment of cancer lays in the effect that it produces in malignant cells. Subjecting them to thermal shock results in activation of numerous degradation processes inside and outside the cell. The heating process initiates mechanisms of DNA destruction, protein denaturation and induction of cell apoptosis, which may lead to tumour shrinkage, and in some cases, it may even cause complete disappearance of cancer. The factors which have the major impact on the final efficiency of the treatment include temperatures generated inside the tissues, time of exposure to the heating process, and the character of an individual cancer cell type. The vast majority of cancer cells is characterised by lower pH, persistent hypoxia and lack of nutrients, which can be associated to abnormal microvasculature. Since in healthy tissues we cannot observe presence of these conditions, they should not be seriously affected by elevation of the temperature. The aim of this work is to investigate the influence of iron content in iron filled Carbon Nanotubes on the desired nanoparticles for cancer therapy. In the article, the development and demonstration of the method and the model device for hyperthermic selective destruction of cancer cells are presented. This method was based on the synthesis and functionalization of carbon nanotubes serving as ferromagnetic material nanocontainers. The methodology of the production carbon- ferromagnetic nanocontainers (FNCs) includes the synthesis of carbon nanotubes, chemical, and physical characterization, increasing the content of a ferromagnetic material and biochemical functionalization involving the attachment of the key addresses. The ferromagnetic nanocontainers were synthesised in CVD and microwave plasma system. The research work has been financed from the budget of science as a research project No. PBS2/A5/31/2013.Keywords: hyperthermia, carbon nanotubes, cancer colon cells, radio frequency field
Procedia PDF Downloads 1231797 Analysis of Force Convection in Bandung Triga Reactor Core Plate Types Fueled Using Coolod-N2
Authors: K. A. Sudjatmi, Endiah Puji Hastuti, Surip Widodo, Reinaldy Nazar
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Any pretensions to stop the production of TRIGA fuel elements by TRIGA reactor fuel elements manufacturer should be anticipated by the operating agency of TRIGA reactor to replace the cylinder type fuel element with plate type fuel element, that available on the market. This away was performed the calculation on U3Si2Al fuel with uranium enrichment of 19.75% and a load level of 2.96 gU/cm3. Maximum power that can be operated on free convection cooling mode at the BANDUNG TRIGA reactor fuel plate was 600 kW. This study has been conducted thermalhydraulic characteristic calculation model of the reactor core power 2MW. BANDUNG TRIGA reactor core fueled plate type is composed of 16 fuel elements, 4 control elements and one irradiation facility which is located right in the middle of the core. The reactor core is cooled using a pump which is already available with flow rate 900 gpm. Analysis on forced convection cooling mode with flow from the top down from 10%, 20%, 30% and so on up to a 100% rate of coolant flow. performed using the COOLOD-N2 code. The calculations result showed that the 2 MW power with inlet coolant temperature at 37 °C and cooling rate percentage of 50%, then the coolant temperature, maximum cladding and meat respectively 64.96 oC, 124.81 oC, and 125.08 oC, DNBR (departure from nucleate boiling ratio)=1.23 and OFIR (onset of flow instability ratio)=1:00. The results are expected to be used as a reference for determining the power and cooling rate level of the BANDUNG TRIGA reactor core plate types fueled.Keywords: TRIGA, COOLOD-N2, plate type fuel element, force convection, thermal hydraulic characteristic
Procedia PDF Downloads 3011796 Crustal Deformation Study across the Chite Fault Using GPS Measurements in North East India along the Indo Burmese Arc
Authors: Malsawmtluanga, J. Malsawma, R. P. Tiwari, V. K. Gahalaut
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North East India is seismically one of the six most active regions of the world. It is placed in Zone V, the highest zone in the seismic zonation of India. It lies at the junction of Himalayan arc to the north and the Burmese arc to the east. The region has witnessed at least 18 large earthquakes including two great earthquakes Shillong (1987, M=8.7) and the Assam Tibet border (1950, M=8.7).The prominent Chite fault lies at the heart of Aizawl, the capital of Mizoram state and this hilly city is the home to about 2 million people. Geologically the area is a part of the Indo-Burmese Wedge and is prone to natural and man-made disasters. Unplanned constructions and urban dwellings on a rapid scale have lead to numerous unsafe structures adversely affecting the ongoing development and welfare projects of the government and they pose a huge threat for earthquakes. Crustal deformation measurements using campaign mode GPS were undertaken across this fault. Campaign mode GPS data were acquired and were processed with GAMIT-GLOBK software. The study presents the current velocity estimates at all the sites in ITRF 2008 and also in the fixed Indian reference frame. The site motion showed that there appears to be no differential motion anywhere across the fault area, thus confirming presently the fault is neither accumulating strain nor slipping aseismically. From the geological and geomorphological evidence, supported by geodetic measurements, lack of historic earthquakes, the Chite fault favours aseismic behaviour in this part of the Indo Burmese Arc (IBA).Keywords: Chite fault, crustal deformation, geodesy, GPS, IBA
Procedia PDF Downloads 2491795 Modeling Route Selection Using Real-Time Information and GPS Data
Authors: William Albeiro Alvarez, Gloria Patricia Jaramillo, Ivan Reinaldo Sarmiento
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Understanding the behavior of individuals and the different human factors that influence the choice when faced with a complex system such as transportation is one of the most complicated aspects of measuring in the components that constitute the modeling of route choice due to that various behaviors and driving mode directly or indirectly affect the choice. During the last two decades, with the development of information and communications technologies, new data collection techniques have emerged such as GPS, geolocation with mobile phones, apps for choosing the route between origin and destination, individual service transport applications among others, where an interest has been generated to improve discrete choice models when considering the incorporation of these developments as well as psychological factors that affect decision making. This paper implements a discrete choice model that proposes and estimates a hybrid model that integrates route choice models and latent variables based on the observation on the route of a sample of public taxi drivers from the city of Medellín, Colombia in relation to its behavior, personality, socioeconomic characteristics, and driving mode. The set of choice options includes the routes generated by the individual service transport applications versus the driver's choice. The hybrid model consists of measurement equations that relate latent variables with measurement indicators and utilities with choice indicators along with structural equations that link the observable characteristics of drivers with latent variables and explanatory variables with utilities.Keywords: behavior choice model, human factors, hybrid model, real time data
Procedia PDF Downloads 1551794 Cardiovascular Disease Prediction Using Machine Learning Approaches
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It is estimated that heart disease accounts for one in ten deaths worldwide. United States deaths due to heart disease are among the leading causes of death according to the World Health Organization. Cardiovascular diseases (CVDs) account for one in four U.S. deaths, according to the Centers for Disease Control and Prevention (CDC). According to statistics, women are more likely than men to die from heart disease as a result of strokes. A 50% increase in men's mortality was reported by the World Health Organization in 2009. The consequences of cardiovascular disease are severe. The causes of heart disease include diabetes, high blood pressure, high cholesterol, abnormal pulse rates, etc. Machine learning (ML) can be used to make predictions and decisions in the healthcare industry. Thus, scientists have turned to modern technologies like Machine Learning and Data Mining to predict diseases. The disease prediction is based on four algorithms. Compared to other boosts, the Ada boost is much more accurate.Keywords: heart disease, cardiovascular disease, coronary artery disease, feature selection, random forest, AdaBoost, SVM, decision tree
Procedia PDF Downloads 1541793 Prismatic Bifurcation Study of a Functionally Graded Dielectric Elastomeric Tube Using Linearized Incremental Theory of Deformations
Authors: Sanjeet Patra, Soham Roychowdhury
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In recent times, functionally graded dielectric elastomer (FGDE) has gained significant attention within the realm of soft actuation due to its dual capacity to exert highly localized stresses while maintaining its compliant characteristics on application of electro-mechanical loading. Nevertheless, the full potential of dielectric elastomer (DE) has not been fully explored due to their susceptibility to instabilities when subjected to electro-mechanical loads. As a result, study and analysis of such instabilities becomes crucial for the design and realization of dielectric actuators. Prismatic bifurcation is a type of instability that has been recognized in a DE tube. Though several studies have reported on the analysis for prismatic bifurcation in an isotropic DE tube, there is an insufficiency in studies related to prismatic bifurcation of FGDE tubes. Therefore, this paper aims to determine the onset of prismatic bifurcations on an incompressible FGDE tube when subjected to electrical loading across the thickness of the tube and internal pressurization. The analysis has been conducted by imposing two axial boundary conditions on the tube, specifically axially free ends and axially clamped ends. Additionally, the rigidity modulus of the tube has been linearly graded in the direction of thickness where the inner surface of the tube has a lower stiffness than the outer surface. The static equilibrium equations for deformation of the axisymmetric tube are derived and solved using numerical technique. The condition for prismatic bifurcation of the axisymmetric static equilibrium solutions has been obtained by using the linearized incremental constitutive equations. Two modes of bifurcations, corresponding to two different non-circular cross-sectional geometries, have been explored in this study. The outcomes reveal that the FGDE tubes experiences prismatic bifurcation before the Hessian criterion of failure is satisfied. It is observed that the lower mode of bifurcation can be triggered at a lower critical voltage as compared to the higher mode of bifurcation. Furthermore, the tubes with larger stiffness gradient require higher critical voltages for triggering the bifurcation. Moreover, with the increase in stiffness gradient, a linear variation of the critical voltage is observed with the thickness of the tube. It has been found that on applying internal pressure to a tube with low thickness, the tube becomes less susceptible to bifurcations. A thicker tube with axially free end is found to be more stable than the axially clamped end tube at higher mode of bifurcation.Keywords: critical voltage, functionally graded dielectric elastomer, linearized incremental approach, modulus of rigidity, prismatic bifurcation
Procedia PDF Downloads 801792 The Study of X- Bracing on Limit State Behaviour of Buckling Restrained Brace (BRB) in Steel Frames Using Pushover Analysis
Authors: Peyman Shadman Heidari, Hamid Bastani, Pouya Shadman Heidari
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Nowadays, using energy dampers in structures is highly considered for the dissipation and absorption of earthquake energy. The main advantage of using energy damper is absorbing the earthquake energy in some sections apart from the structure frame. Among different types of dampers, hysteresis dampers are of special place because of low cost, high reliability and the lack of mechanical parts. In this paper, a special kind of hysteresis damper is considered under the name of buckling brace, which is provided with the aim of the study and investigation of cross braces in boundary behaviour of steel frames using nonlinear static analysis. In this paper, ninety three models of steel frames with cross braces of buckling type are processed with different bays and heights and their plasticity index, behaviour coefficient, distribution type and the number of plastic hinges formed were calculated. Finally, the mean behaviour coefficient was compared with standard behaviour coefficient of 2800 and the suitable mode of braces placing in improving nonlinear behaviour and suitable distribution of plastic hinges were presented. In addition, it was determined that for some placing mode of braces the behaviour coefficient will increase to 15 times of recommended 2800 standard coefficient and in some placing modes, the braced bays will show considerable difference with suggested 2800 standard behaviour coefficient relative to each other.Keywords: buckling restrained brace, plasticity index, behaviour coefficient, resistance coefficient, plastic joints
Procedia PDF Downloads 5141791 Renovation of Industrial Zones in Ho Chi Minh City: An Approach from Changing Function of Processing to Urban Warehousing
Authors: Thu Le Thi Bao
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Industrial parks have both active roles in promoting economic development and source of appearance of boarding houses and slums in the adjacent area, lacking infrastructure, causing many social evils. The context of the recent pandemic and climate change on a global scale pose issues that need to be resolved for sustainable development. Ho Chi Minh City aims to develop housing for migrant workers to stabilize human resources and, at the same time, solve problems of social evils caused by poor living conditions. The paper focuses on the content of renovating existing industrial parks and worker accommodation in Ho Chi Minh City to propose appropriate models, contributing to the goal of urban embellishment and solutions for industrial parks to adapt to abnormal impact conditions such as pandemics, climate change, crises.Keywords: industrial park, social housing, accommodation, distribution center
Procedia PDF Downloads 1131790 Text Mining Past Medical History in Electrophysiological Studies
Authors: Roni Ramon-Gonen, Amir Dori, Shahar Shelly
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Background and objectives: Healthcare professionals produce abundant textual information in their daily clinical practice. The extraction of insights from all the gathered information, mainly unstructured and lacking in normalization, is one of the major challenges in computational medicine. In this respect, text mining assembles different techniques to derive valuable insights from unstructured textual data, so it has led to being especially relevant in Medicine. Neurological patient’s history allows the clinician to define the patient’s symptoms and along with the result of the nerve conduction study (NCS) and electromyography (EMG) test, assists in formulating a differential diagnosis. Past medical history (PMH) helps to direct the latter. In this study, we aimed to identify relevant PMH, understand which PMHs are common among patients in the referral cohort and documented by the medical staff, and examine the differences by sex and age in a large cohort based on textual format notes. Methods: We retrospectively identified all patients with abnormal NCS between May 2016 to February 2022. Age, gender, and all NCS attributes reports were recorded, including the summary text. All patients’ histories were extracted from the text report by a query. Basic text cleansing and data preparation were performed, as well as lemmatization. Very popular words (like ‘left’ and ‘right’) were deleted. Several words were replaced with their abbreviations. A bag of words approach was used to perform the analyses. Different visualizations which are common in text analysis, were created to easily grasp the results. Results: We identified 5282 unique patients. Three thousand and five (57%) patients had documented PMH. Of which 60.4% (n=1817) were males. The total median age was 62 years (range 0.12 – 97.2 years), and the majority of patients (83%) presented after the age of forty years. The top two documented medical histories were diabetes mellitus (DM) and surgery. DM was observed in 16.3% of the patients, and surgery at 15.4%. Other frequent patient histories (among the top 20) were fracture, cancer (ca), motor vehicle accident (MVA), leg, lumbar, discopathy, back and carpal tunnel release (CTR). When separating the data by sex, we can see that DM and MVA are more frequent among males, while cancer and CTR are less frequent. On the other hand, the top medical history in females was surgery and, after that, DM. Other frequent histories among females are breast cancer, fractures, and CTR. In the younger population (ages 18 to 26), the frequent PMH were surgery, fractures, trauma, and MVA. Discussion: By applying text mining approaches to unstructured data, we were able to better understand which medical histories are more relevant in these circumstances and, in addition, gain additional insights regarding sex and age differences. These insights might help to collect epidemiological demographical data as well as raise new hypotheses. One limitation of this work is that each clinician might use different words or abbreviations to describe the same condition, and therefore using a coding system can be beneficial.Keywords: abnormal studies, healthcare analytics, medical history, nerve conduction studies, text mining, textual analysis
Procedia PDF Downloads 961789 The Relationship between the Epithermal Mineralization, Thermalism, and Basement Faults in the Region of Guelma: NE of Algeria
Authors: B. Merdas
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The Guelma region constitutes a vast geothermal field whose local geothermal gradient is very high. Indeed, various thermal and thermo sources emerging in the region, including some at relatively high temperatures. In the mio Pliocene Hammam N'bails, basin emerges a hot spring that leaves develop a thick series of thermal travertine linked to it. Near the thermal emergences has settled a very special mineralization antimony and zinc and lead. The results of analyses of the thermal waters of the source of Hammam N'bails and the associated travertine, show abnormal values in Pb, Sb, Zn, As, and other metals, demonstrating the genetic link between those waters and mineralization. Hammam N'bails mineralizations by their mineral assembling represented and their association with the hot springs, are very similar to epithermal deposits with precious metals (gold and silver) like Senator mine in Turkey or ‘Carlin-type’ in Nevada (USA).Keywords: hot springs, mineralization; basement faults, Guelma, NE Algeria
Procedia PDF Downloads 4311788 Spatial Direct Numerical Simulation of Instability Waves in Hypersonic Boundary Layers
Authors: Jayahar Sivasubramanian
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Understanding laminar-turbulent transition process in hyper-sonic boundary layers is crucial for designing viable high speed flight vehicles. The study of transition becomes particularly important in the high speed regime due to the effect of transition on aerodynamic performance and heat transfer. However, even after many years of research, the transition process in hyper-sonic boundary layers is still not understood. This lack of understanding of the physics of the transition process is a major impediment to the development of reliable transition prediction methods. Towards this end, spatial Direct Numerical Simulations are conducted to investigate the instability waves generated by a localized disturbance in a hyper-sonic flat plate boundary layer. In order to model a natural transition scenario, the boundary layer was forced by a short duration (localized) pulse through a hole on the surface of the flat plate. The pulse disturbance developed into a three-dimensional instability wave packet which consisted of a wide range of disturbance frequencies and wave numbers. First, the linear development of the wave packet was studied by forcing the flow with low amplitude (0.001% of the free-stream velocity). The dominant waves within the resulting wave packet were identified as two-dimensional second mode disturbance waves. Hence the wall-pressure disturbance spectrum exhibited a maximum at the span wise mode number k = 0. The spectrum broadened in downstream direction and the lower frequency first mode oblique waves were also identified in the spectrum. However, the peak amplitude remained at k = 0 which shifted to lower frequencies in the downstream direction. In order to investigate the nonlinear transition regime, the flow was forced with a higher amplitude disturbance (5% of the free-stream velocity). The developing wave packet grows linearly at first before reaching the nonlinear regime. The wall pressure disturbance spectrum confirmed that the wave packet developed linearly at first. The response of the flow to the high amplitude pulse disturbance indicated the presence of a fundamental resonance mechanism. Lower amplitude secondary peaks were also identified in the disturbance wave spectrum at approximately half the frequency of the high amplitude frequency band, which would be an indication of a sub-harmonic resonance mechanism. The disturbance spectrum indicates, however, that fundamental resonance is much stronger than sub-harmonic resonance.Keywords: boundary layer, DNS, hyper sonic flow, instability waves, wave packet
Procedia PDF Downloads 183