Search results for: radio frequency sputtering.
3553 Solar Wind Turbulence and the Role of Circularly Polarized Dispersive Alfvén Wave
Authors: Swati Sharma, R. P. Sharma
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We intend to study the nonlinear evolution of the parallel propagating finite frequency Alfvén wave (also called Dispersive Alfvén wave/Hall MHD wave) propagating in the solar wind regime of the solar region when a perpendicularly propagating magnetosonic wave is present in the background. The finite frequency Alfvén wave behaves differently from the usual non-dispersive behavior of the Alfvén wave. To study the nonlinear processes (such as filamentation) taking place in the solar regions such as solar wind, the dynamical equation of both the waves are derived. Numerical simulation involving finite difference method for the time domain and pseudo spectral method for the spatial domain is then performed to analyze the transient evolution of these waves. The power spectra of the Dispersive Alfvén wave is also investigated. The power spectra shows the distribution of the magnetic field intensity of the Dispersive Alfvén wave over different wave numbers. For DAW the spectra shows a steepening for scales larger than the proton inertial length. This means that the wave energy gets transferred to the solar wind particles as the wave reaches higher wave numbers. This steepening of the power spectra can be explained on account of the finite frequency of the Alfvén wave. The obtained results are consistent with the observations made by CLUSTER spacecraft.Keywords: solar wind, turbulence, dispersive alfven wave
Procedia PDF Downloads 6003552 The Implantable MEMS Blood Pressure Sensor Model With Wireless Powering And Data Transmission
Authors: Vitaliy Petrov, Natalia Shusharina, Vitaliy Kasymov, Maksim Patrushev, Evgeny Bogdanov
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The leading worldwide death reasons are ischemic heart disease and other cardiovascular illnesses. Generally, the common symptom is high blood pressure. Long-time blood pressure control is very important for the prophylaxis, correct diagnosis and timely therapy. Non-invasive methods which are based on Korotkoff sounds are impossible to apply often and for a long time. Implantable devices can combine longtime monitoring with high accuracy of measurements. The main purpose of this work is to create a real-time monitoring system for decreasing the death rate from cardiovascular diseases. These days implantable electronic devices began to play an important role in medicine. Usually implantable devices consist of a transmitter, powering which could be wireless with a special made battery and measurement circuit. Common problems in making implantable devices are short lifetime of the battery, big size and biocompatibility. In these work, blood pressure measure will be the focus because it’s one of the main symptoms of cardiovascular diseases. Our device will consist of three parts: the implantable pressure sensor, external transmitter and automated workstation in a hospital. The Implantable part of pressure sensors could be based on piezoresistive or capacitive technologies. Both sensors have some advantages and some limitations. The Developed circuit is based on a small capacitive sensor which is made of the technology of microelectromechanical systems (MEMS). The Capacitive sensor can provide high sensitivity, low power consumption and minimum hysteresis compared to the piezoresistive sensor. For this device, it was selected the oscillator-based circuit where frequency depends from the capacitance of sensor hence from capacitance one can calculate pressure. The external device (transmitter) used for wireless charging and signal transmission. Some implant devices for these applications are passive, the external device sends radio wave signal on internal LC circuit device. The external device gets reflected the signal from the implant and from a change of frequency is possible to calculate changing of capacitance and then blood pressure. However, this method has some disadvantages, such as the patient position dependence and static using. Developed implantable device doesn’t have these disadvantages and sends blood pressure data to the external part in real-time. The external device continuously sends information about blood pressure to hospital cloud service for analysis by a physician. Doctor’s automated workstation at the hospital also acts as a dashboard, which displays actual medical data of patients (which require attention) and stores it in cloud service. Usually, critical heart conditions occur few hours before heart attack but the device is able to send an alarm signal to the hospital for an early action of medical service. The system was tested with wireless charging and data transmission. These results can be used for ASIC design for MEMS pressure sensor.Keywords: MEMS sensor, RF power, wireless data, oscillator-based circuit
Procedia PDF Downloads 5893551 The Effects of Expanding the Generosity of the Statutory Sick Leave Insurance: The Case of a French Reform
Authors: Mohamed Ali Benhalima, Nathon Elbaz, Malik Koubi
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This paper evaluates an expansion of employer-mandated sick leave insurance in the French private sector. We use a difference-in-differences method in which control groups are defined according to the collective bargaining agreement (CBA) employees belong to. Indeed, thanks to complementary insurance provided by CBAs, employees were not affected the same way by the reform. We find significant effects of the reform on sick leave spells lasting at least 7 days, consistently with the reform target. The effects on spells’ duration and frequency are positive and more pronounced for women than for men, for whom the effect on frequency tends to be slightly negative. The effects are also more pronounced for executives and supervisors than less qualified categories.Keywords: sickness absence, collective agreements, daily sickness benefits, labor economics
Procedia PDF Downloads 3533550 Parametric Analysis and Optimal Design of Functionally Graded Plates Using Particle Swarm Optimization Algorithm and a Hybrid Meshless Method
Authors: Foad Nazari, Seyed Mahmood Hosseini, Mohammad Hossein Abolbashari, Mohammad Hassan Abolbashari
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The present study is concerned with the optimal design of functionally graded plates using particle swarm optimization (PSO) algorithm. In this study, meshless local Petrov-Galerkin (MLPG) method is employed to obtain the functionally graded (FG) plate’s natural frequencies. Effects of two parameters including thickness to height ratio and volume fraction index on the natural frequencies and total mass of plate are studied by using the MLPG results. Then the first natural frequency of the plate, for different conditions where MLPG data are not available, is predicted by an artificial neural network (ANN) approach which is trained by back-error propagation (BEP) technique. The ANN results show that the predicted data are in good agreement with the actual one. To maximize the first natural frequency and minimize the mass of FG plate simultaneously, the weighted sum optimization approach and PSO algorithm are used. However, the proposed optimization process of this study can provide the designers of FG plates with useful data.Keywords: optimal design, natural frequency, FG plate, hybrid meshless method, MLPG method, ANN approach, particle swarm optimization
Procedia PDF Downloads 3673549 Design and Fabrication of an Electrostatically Actuated Parallel-Plate Mirror by 3D-Printer
Authors: J. Mizuno, S. Takahashi
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In this paper, design and fabrication of an actuated parallel-plate mirror based on a 3D-printer is described. The mirror and electrode layers are fabricated separately and assembled thereafter. The alignment is performed by dowel pin-hole pairs fabricated on the respective layers. The electrodes are formed on the surface of the electrode layer by Au ion sputtering using a suitable mask, which is also fabricated by a 3D-printer.For grounding the mirror layer, except the contact area with the electrode paths, all the surface is Au ion sputtered. 3D-printers are widely used for creating 3D models or mock-ups. The authors have recently proposed that these models can perform electromechanical functions such as actuators by suitably masking them followed by metallization process. Since the smallest possible fabrication size is in the order of sub-millimeters, these electromechanical devices are named by the authors as SMEMS (Sub-Milli Electro-Mechanical Systems) devices. The proposed mirror described in this paper which consists of parallel-plate electrostatic actuators is also one type of SMEMS devices. In addition, SMEMS is totally environment-clean compared to MEMS (Micro Electro-Mechanical Systems) fabrication processes because any hazardous chemicals or gases are utilized.Keywords: MEMS, parallel-plate mirror, SMEMS, 3D-printer
Procedia PDF Downloads 4373548 A Self-Adaptive Stimulus Artifacts Removal Approach for Electrical Stimulation Based Muscle Rehabilitation
Authors: Yinjun Tu, Qiang Fang, Glenn I. Matthews, Shuenn-Yuh Lee
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This paper reports an efficient and rigorous self-adaptive stimulus artifacts removal approach for a mixed surface EMG (Electromyography) and stimulus signal during muscle stimulation. The recording of EMG and the stimulation of muscles were performing simultaneously. It is difficult to generate muscle fatigue feature from the mixed signal, which can be further used in closed loop system. A self-adaptive method is proposed in this paper, the stimulation frequency was calculated and verified firstly. Then, a mask was created based on this stimulation frequency to remove the undesired stimulus. 20 EMG signal recordings were analyzed, and the ANOVA (analysis of variance) approach illustrated that the decreasing trend of median power frequencies was successfully generated from the 'cleaned' EMG signal.Keywords: EMG, FES, stimulus artefacts, self-adaptive
Procedia PDF Downloads 3993547 Investigation of Attitude of Production Workers towards Job Rotation in Automotive Industry against the Background of Demographic Change
Authors: Franciska Weise, Ralph Bruder
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Due to the demographic change in Germany along with the declining birth rate and the increasing age of population, the share of older people in society is rising. This development is also reflected in the work force of German companies. Therefore companies should focus on improving ergonomics, especially in the area of age-related work design. Literature shows that studies on age-related work design have been carried out in the past, some of whose results have been put into practice. However, there is still a need for further research. One of the most important methods for taking into account the needs of an aging population is job rotation. This method aims at preventing or reducing health risks and inappropriate physical strain. It is conceived as a systematic change of workplaces within a group. Existing literature does not cover any methods for the investigation of the attitudes of employees towards job rotation. However, in order to evaluate job rotation, it is essential to have knowledge of the views of people towards rotation. In addition to an investigation of attitudes, the design of rotation plays a crucial role. The sequence of activities and the rotation frequency influence the worker and as well the work result. The evaluation of preliminary talks on the shop floor showed that team speakers and foremen share a common understanding of job rotation. In practice, different varieties of job rotation exist. One important aspect is the frequency of rotation. It is possible to rotate never, more than one time or even during every break, or more often than every break. It depends on the opportunity or possibility to rotate whenever workers want to rotate. From the preliminary talks some challenges can be derived. For example a rotation in the whole team is not possible, if a team member requires to be trained for a new task. In order to be able to determine the relation of the design and the attitude towards job rotation, a questionnaire is carried out in the vehicle manufacturing. The questionnaire will be employed to determine the different varieties of job rotation that exist in production, as well as the attitudes of workers towards those different frequencies of job rotation. In addition, younger and older employees will be compared with regard to their rotation frequency and their attitudes towards rotation. There are three kinds of age groups. Three questions are under examination. The first question is whether older employees rotate less frequently than younger employees. Also it is investigated to know whether the frequency of job rotation and the attitude towards the frequency of job rotation are interconnected. Moreover, the attitudes of the different age groups towards the frequency of rotation will be examined. Up to now 144 employees, all working in production, took part in the survey. 36.8 % were younger than thirty, 37.5 % were between thirty und forty-four and 25.7 % were above forty-five years old. The data shows no difference between the three age groups in relation to the frequency of job rotation (N=139, median=4, Chi²=.859, df=2, p=.651). Most employees rotate between six and seven workplaces per day. In addition there is a statistically significant correlation between the frequency of job rotation and the attitude towards the frequency (Spearman-Rho: 2-sided=.008, correlation coefficient=.223). Less than four workplaces per day are not enough for the employees. The third question, which differences can be found between older and younger people who rotate in a different way and with different attitudes towards job rotation, cannot be possible answered. Till now the data shows that younger people would like to rotate very often. Regarding to older people no correlation can be found with acceptable significance. The results of the survey will be used to improve the current practice of job rotation. In addition, the discussions during the survey are expected to help sensitize the employees with respect to rotation issues, and to contribute to optimizing rotation by means of qualification and an improved design of job rotation. Together with the employees and the results of the survey there must be found standards which show how to rotate in an ergonomic way while consider the attitude towards job rotation.Keywords: job rotation, age-related work design, questionnaire, automotive industry
Procedia PDF Downloads 3033546 Electrical and Optical Properties of Polyaniline: Cadmium Sulphide Quantum Dots Nanocomposites
Authors: Akhtar Rasool, Tasneem Zahra Rizvi
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In this study, a series of the cadmium sulphide quantum dots/polyaniline nanocomposites with varying compositions were prepared by in-situ polymerization technique and were characterized using X-ray diffraction and Fourier transform infrared spectroscopy. The surface morphology was studied by scanning electron microscopy. UV-Visible spectroscopy was used to find out the energy band gap of the nanoparticles and the nanocomposites. Temperature dependence of DC electrical conductivity and temperature and frequency dependence of AC conductivity were investigated to study the charge transport mechanism in the nanocomposites. DC conductivity was found to be a typical for a semiconducting behavior following Mott’s 1D variable range hoping model. The frequency dependent AC conductivity followed the universal power law.Keywords: conducting polymers, nanocomposites, polyaniline composites, quantum dots
Procedia PDF Downloads 2543545 Multiband Prefractal Microstrip Antenna for Wireless Applications
Authors: Yadwinder Kumar, Priyanka Rani Amandeep Singh
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In this paper the design of a multiband pre-fractal micro strip antenna with proximity coupling feed is presented. The proposed antenna resonates on seven different frequencies that are 2.6 GHz, 5.1 GHz, 9.4 GHz, 11.5 GHz, 13.8 GHz, 16.3 GHz, and 18.6 GHz. Simulated results presented here shows that the minimum return loss is achieved at the 16.3 GHz frequency which is up to 37 dB. Also the maximum band width of 700 MHz is achieved by the frequency bands 13.4 GHz to 14.1 GHz, 15.9 GHz to 16.6 GHz and 18.2 GHz to 18.9 GHz. The proposed feed line is sandwiched between two substrate layers and increases in the bandwidth of antenna has been observed up to 13% in comparison of micro strip feed line. Effect of key design parameters such as variation in substrate material, substrate height and feeding technique on antenna S-parameter have been investigated and discussed.Keywords: fractal antenna, pre-fractals, micro strip antenna, ISM band, electromagnetic coupling, VSWR
Procedia PDF Downloads 5883544 Regularities of Changes in the Fractal Dimension of Acoustic Emission Signals in the Stages Close to the Destruction of Structural Materials When Exposed to Low-Cycle Loaded
Authors: Phyo Wai Aung, Sysoev Oleg Evgenevich, Boris Necolavet Maryin
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The article deals with theoretical problems of correlation of processes of microstructure changes of structural materials under cyclic loading and acoustic emission. The ways of the evolution of a microstructure under the influence of cyclic loading are shown depending on the structure of the initial crystal structure of the material. The spectra of the frequency characteristics of acoustic emission signals are experimentally obtained when testing titanium samples for cyclic loads. Changes in the fractal dimension of the acoustic emission signals in the selected frequency bands during the evolution of the microstructure of structural materials from the action of cyclic loads, as well as in the destruction of samples, are studied. The experimental samples were made of VT-20 structural material widely used in aircraft and rocket engineering. The article shows the striving of structural materials for synergistic stability and reduction of the fractal dimension of acoustic emission signals, in accordance with the degradation of the microstructure, which occurs as a result of fatigue processes from the action of low cycle loads. As a result of the research, the frequency range of acoustic emission signals of 100-270 kHz is determined, in which the fractal dimension of the signals, it is possible to most reliably predict the durability of structural materials.Keywords: cyclic loadings, material structure changing, acoustic emission, fractal dimension
Procedia PDF Downloads 2623543 Development of a Large-Scale Cyclic Shear Testing Machine Under Constant Normal Stiffness
Authors: S. M. Mahdi Niktabara, K. Seshagiri Raob, Amit Kumar Shrivastavac, Jiří Ščučkaa
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The presence of the discontinuity in the form of joints is one of the most significant factors causing instability in the rock mass. On the other hand, dynamic loads, including earthquake and blasting induce cyclic shear loads along the joints in rock masses; therefore, failure of rock mass exacerbates along the joints due to changing shear resistance. Joints are under constant normal load (CNL) and constant normal stiffness (CNS) conditions. Normal stiffness increases on the joints with increasing depth, and it can affect shear resistance. For correct assessment of joint shear resistance under varying normal stiffness and number of cycles, advanced laboratory shear machine is essential for the shear test. Conventional direct shear equipment has limitations such as boundary conditions, working under monotonic movements only, or cyclic shear loads with constant frequency and amplitude of shear loads. Hence, a large-scale servo-controlled direct shear testing machine was designed and fabricated to perform shear test under the both CNL and CNS conditions with varying normal stiffness at different frequencies and amplitudes of shear loads. In this study, laboratory cyclic shear tests were conducted on non-planar joints under varying normal stiffness. In addition, the effects of different frequencies and amplitudes of shear loads were investigated. The test results indicate that shear resistance increases with increasing normal stiffness at the first cycle, but the influence of normal stiffness significantly decreases with an increase in the number of shear cycles. The frequency of shear load influences on shear resistance, i.e. shear resistance increases with increasing frequency. However, at low shear amplitude the number of cycles does not affect shear resistance on the joints, but it decreases with higher amplitude.Keywords: cyclic shear load, frequency of load, amplitude of displacement, normal stiffness
Procedia PDF Downloads 1513542 PWM Harmonic Injection and Frequency-Modulated Triangular Carrier to Improve the Lives of the Transformers
Authors: Mario J. Meco-Gutierrez, Francisco Perez-Hidalgo, Juan R. Heredia-Larrubia, Antonio Ruiz-Gonzalez, Francisco Vargas-Merino
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More and more applications power inverters connected to transformers, for example, the connection facilities to the power grid renewable generation. It is well known that the quality of signal power inverters it is not a pure sine. The harmonic content produced negative effects, one of which is the heating of electrical machines and therefore, affects the life of the machines. The decrease of life of transformers can be calculated by Arrhenius or Montsinger equation. Analyzing this expression any (long-term) decrease of a transformer temperature for 6º C - 7º C means doubles its life-expectancy. Methodologies: This work presents the technique of pulse width modulation (PWM) with an injection of harmonic and triangular frequency carrier modulated in frequency. This technique is used to improve the quality of the output voltage signal of the power inverters controlled PWM. The proposed technique increases in the fundamental term and a significant reduction in low order harmonics with the same commutations per time that control sine PWM. To achieve this, the modulating wave is compared to a triangular carrier with variable frequency over the period of the modulator. Therefore, it is, advantageous for the modulating signal to have a large amount of sinusoidal “information” in the areas of greater sampling. A triangular signal with a frequency that varies over the modulator’s period is used as a carrier, for obtaining more samples in the area with the greatest slope. A power inverter controlled by PWM proposed technique is connected to a transformer. Results: In order to verify the derived thermal parameters under different operation conditions, another ambient and loading scenario is involved for a further verification, which was sampled from the same power transformer. Temperatures of different parts of the transformer will be exposed for each PWM control technique analyzed. An assessment of the temperature be done with different techniques PWM control and hence the life of the transformer is calculated for each technique. Conclusion: This paper analyzes such as transformer heating produced by this technique and compared with other forms of PWM control. In it can be seen as a reduction the harmonic content produces less heat transformer and therefore, an increase in the life of the transformer.Keywords: heating, power-inverter, PWM, transformer
Procedia PDF Downloads 4123541 Influence of 50 Hz, 1m Tesla Electromagnetic Fields on Serum Male Sex Hormones of Male Rats
Authors: Randa M. Mostafa, Y. Moustafa
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During our daily life, we are continuously exposed to the extremely low frequency electromagnetic fields (ELF-EMFs) generated by electric appliances. The possible relation between exposure to (ELF-MFs) and adverse health effects has attracted and passed through long debate sessions. Extremely low frequency is a term used to describe radiation frequencies below 300 Hertz (Hz).It is very important for public health because of the widespread use of electrical power at 50-60 Hz in most countries. This study set out to investigate the impact of chronic exposure of male rats to 50- Hz, 1 mTesla (ELF-EMF) of over periods of 1, 2, and 4 weeks on concentration of serum FSH, LH, and testosterone hormones. 60 male albino rats were divided into 6 groups and were continuously exposed to 50-Hz, 1 m Tesla (ELF-EMF) generated by magnetic field chamber for periods of 1, 2, and 4 weeks. For each experimental point, sham treated group was used as a control. Assay of serum testosterone LH, and FSHwere performed. Serum testosterone showed no significant changes. FSH showed significant increase than sham exposed group after 1 week of field exposure. LH showed significant increase than sham exposed group only after 4 weeks of field exposure. A future detailed molecular studies must be carried out to figure out and may be able to explain the possible interactions between ELF-EMF and hypothalamic-pituitary gonadal axis.Keywords: extremely low frequency electromagnetic fields, testosterone, follicular stimulating hormone, LH
Procedia PDF Downloads 4603540 Fuzzy Sliding Mode Control of a Flexible Structure for Vibration Suppression Using MFC Actuator
Authors: Jinsiang Shaw, Shih-Chieh Tseng
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Active vibration control is good for low frequency excitation, with advantages of light weight and adaptability. This paper use a macro-fiber composite (MFC) actuator for vibration suppression in a cantilevered beam due to its higher output force to suppress the disturbance. A fuzzy sliding mode controller is developed and applied to this system. Experimental results illustrate that the controller and MFC actuator are very effective in attenuating the structural vibration near the first resonant freuqency. Furthermore, this controller is shown to outperform the traditional skyhook controller, with nearly 90% of the vibration suppressed at the first resonant frequency of the structure.Keywords: Fuzzy sliding mode controller, macro-fiber-composite actuator, skyhook controller, vibration suppression
Procedia PDF Downloads 4033539 Structural Properties of RC Beam with Progression of Corrosion Induced Delamination Cracking
Authors: Anupam Saxena, Achin Agrawal, Rishabh Shukla, S. Mandal
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It is quite important that the properties of structural elements do not change significantly before and after cracking, and if they do, it adversely affects the structure. Corrosion in rebars causes cracking in concrete which can lead to the change in properties of beam. In the present study, two RC beams with same flexural strength but with different reinforcement arrangements are considered and modelling of cracks of RC beams has been done at different degrees of corrosion in the case of delamination using boundary conditions of Three Point Bending Test. Finite Element Analysis (FEA) has been done at different degree of corrosion to observe the variation of different parameters like modal frequency, Elasticity and Flexural strength in case of delamination. Also, the comparison between two different RC arrangements is made to conclude which one of them is more suitable.Keywords: delamination, elasticity, FEA, flexural strength, modal frequency, RC beam
Procedia PDF Downloads 4263538 Frequency of Polymorphism of Mrp1/Abcc1 And Mrp2/Abcc2 in Healthy Volunteers of the Center Savannah (Colombia)
Authors: R. H. Bustos, L. Martinez, J. García, F. Suárez
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MRP1 (Multi-drug resistance associated protein 1) and MRP2 (Multi-drug resistance associated protein 2) are two proteins belonging to the transporters of ABC (ATP-Binding Cassette). These transporter proteins are involved in the efflux of several biological drugs and xenobiotic and also in multiple physiological, pathological and pharmacological processes. Evidence has been found that there is a correlation among different polymorphisms found and their clinical implication in the resistance to antiepileptic, chemotherapy and anti-infectious drugs. In our study, exonic regions of MRP1/ABCC1 y MRP2/ABCC2 were studied in the Colombian population, specifically in the region of the central Savannah (Cundinamarca) to determinate SNP (Single Nucleotide Polymorphisms) and determinate its allele frequency and its genomics frequency. Results showed that for our population, SNP are found that have been previously reported for MRP1/ABCC1 (rs200647436, rs200624910, rs150214567) as well as for MRP2/ABCC2 (rs2273697, rs3740066, rs142573385, rs17216212). In addition, 13 new SNP were identified. Evidences show an important clinic correlation for polymorphisms rs3740066 and rs2273697. The study object population displays genetic variability as compared to the one reported in other populations.Keywords: ATP-binding cassette (ABCC), Colombian population, multidrug-resistance protein (MRP), pharmacogenetic, single nucleotide polymorphism (SNP)
Procedia PDF Downloads 3243537 Vibration Control of a Flexible Structure Using MFC Actuator
Authors: Jinsiang Shaw, Jeng-Jie Huang
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Active vibration control is good for low frequency excitation, with advantages of light weight and adaptability. This paper employs a macro-fiber composite (MFC) actuator for vibration suppression in a cantilevered beam due to its higher output force to reject the disturbance. A notch filter with an adaptive tuning algorithm, the leaky filtered-X least mean square algorithm (leaky FXLMS algorithm), is developed and applied to the system. Experimental results show that the controller and MFC actuator was very effective in attenuating the structural vibration. Furthermore, this notch filter controller was compared with the traditional skyhook controller. It was found that its performance was better, with over 88% vibration suppression near the first resonant frequency of the structure.Keywords: macro-fiber composite, notch filter, skyhook controller, vibration suppression
Procedia PDF Downloads 4623536 Bridge Damage Detection and Stiffness Reduction Using Vibration Data: Experimental Investigation on a Small Scale Steel Bridge
Authors: Mirco Tarozzi, Giacomo Pignagnoli, Andrea Benedetti
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The design of planning maintenance of civil structures often requires the evaluation of their level of safety in order to be able to choose which structure, and in which measure, it needs a structural retrofit. This work deals with the evaluation of the stiffness reduction of a scaled steel deck due to the presence of localized damages. The dynamic tests performed on it have shown the variability of its main frequencies linked to the gradual reduction of its rigidity. This deck consists in a steel grillage of four secondary beams and three main beams linked to a concrete slab. This steel deck is 6 m long and 3 m wide and it rests on two abutments made of concrete. By processing the signals of the accelerations due to a random excitation of the deck, the main natural frequencies of this bridge have been extracted. In order to assign more reliable parameters to the numerical model of the deck, some load tests have been performed and the mechanical property of the materials and the supports have been obtained. The two external beams have been cut at one third of their length and the structural strength has been restored by the design of a bolted plate. The gradual loss of the bolts and the plates removal have made the simulation of localized damage possible. In order to define the relationship between frequency variation and loss in stiffness, the identification of its natural frequencies has been performed, before and after the occurrence of the damage, corresponding to each step. The study of the relationship between stiffness losses and frequency shifts has been reported in this paper: the square of the frequency variation due to the presence of the damage is proportional to the ratio between the rigidities. This relationship can be used to quantify the loss in stiffness of a real scale bridge in an efficient way.Keywords: damage detection, dynamic test, frequency shifts, operational modal analysis, steel bridge
Procedia PDF Downloads 1603535 Seismic Microzonation Analysis for Damage Mapping of the 2006 Yogyakarta Earthquake, Indonesia
Authors: Fathul Mubin, Budi E. Nurcahya
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In 2006, a large earthquake ever occurred in the province of Yogyakarta, which caused considerable damage. This is the basis need to investigate the seismic vulnerability index in around of the earthquake zone. This research is called microzonation of earthquake hazard. This research has been conducted at the site and surrounding of Prambanan Temple, includes homes and civil buildings. The reason this research needs to be done because in the event of an earthquake in 2006, there was damage to the temples at Prambanan temple complex and its surroundings. In this research, data collection carried out for 60 minutes using three component seismograph measurements at 165 points with spacing of 1000 meters. The data recorded in time function were analyzed using the spectral ratio method, known as the Horizontal to Vertical Spectral Ratio (HVSR). Results from this analysis are dominant frequency (Fg) and maximum amplification factor (Ag) are used to obtain seismic vulnerability index. The results of research showed the dominant frequency range from 0.5 to 30 Hz and the amplification is in interval from 0.5 to 9. Interval value for seismic vulnerability index is 0.1 to 50. Based on distribution maps of seismic vulnerability index and impact of buildings damage seemed for suitability. For further research, it needs to survey to the east (klaten) and south (Bantul, DIY) to determine a full distribution maps of seismic vulnerability index.Keywords: amplification factor, dominant frequency, microzonation analysis, seismic vulnerability index
Procedia PDF Downloads 1943534 Automatic Differential Diagnosis of Melanocytic Skin Tumours Using Ultrasound and Spectrophotometric Data
Authors: Kristina Sakalauskiene, Renaldas Raisutis, Gintare Linkeviciute, Skaidra Valiukeviciene
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Cutaneous melanoma is a melanocytic skin tumour, which has a very poor prognosis while is highly resistant to treatment and tends to metastasize. Thickness of melanoma is one of the most important biomarker for stage of disease, prognosis and surgery planning. In this study, we hypothesized that the automatic analysis of spectrophotometric images and high-frequency ultrasonic 2D data can improve differential diagnosis of cutaneous melanoma and provide additional information about tumour penetration depth. This paper presents the novel complex automatic system for non-invasive melanocytic skin tumour differential diagnosis and penetration depth evaluation. The system is composed of region of interest segmentation in spectrophotometric images and high-frequency ultrasound data, quantitative parameter evaluation, informative feature extraction and classification with linear regression classifier. The segmentation of melanocytic skin tumour region in ultrasound image is based on parametric integrated backscattering coefficient calculation. The segmentation of optical image is based on Otsu thresholding. In total 29 quantitative tissue characterization parameters were evaluated by using ultrasound data (11 acoustical, 4 shape and 15 textural parameters) and 55 quantitative features of dermatoscopic and spectrophotometric images (using total melanin, dermal melanin, blood and collagen SIAgraphs acquired using spectrophotometric imaging device SIAscope). In total 102 melanocytic skin lesions (including 43 cutaneous melanomas) were examined by using SIAscope and ultrasound system with 22 MHz center frequency single element transducer. The diagnosis and Breslow thickness (pT) of each MST were evaluated during routine histological examination after excision and used as a reference. The results of this study have shown that automatic analysis of spectrophotometric and high frequency ultrasound data can improve non-invasive classification accuracy of early-stage cutaneous melanoma and provide supplementary information about tumour penetration depth.Keywords: cutaneous melanoma, differential diagnosis, high-frequency ultrasound, melanocytic skin tumours, spectrophotometric imaging
Procedia PDF Downloads 2703533 Genetic Polymorphism of Milk Protein Gene and Association with Milk Production Traits in Local Latvian Brown Breed Cows
Authors: Daina Jonkus, Solvita Petrovska, Dace Smiltina, Lasma Cielava
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The beta-lactoglobulin and kappa-casein are milk proteins which are important for milk composition. Cows with beta-lactoglobulin and kappa-casein gene BB genotypes have highest milk crude protein and fat content. The aim of the study was to determinate the frequencies of milk protein gene polymorphisms in local Latvian Brown (LB) cows breed and analyze the influence of beta-lactoglobulin and kappa-casein genotypes to milk productivity traits. 102 cows’ genotypes of milk protein genes were detected using Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP) and electrophoresis on 3% agarose gel. For beta-lactoglobulin were observed 2 types of alleles A and B and for kappa-casein 3 types: A, B and E. Highest frequency in beta-lactoglobulin gene was observed for B allele – 0.926. Molecular analysis of beta-lactoglobulin gene shows 86.3% of individuals are homozygous by B allele and animals are with genotypes BB and 12.7% of individuals are heterozygous with genotypes AB. The highest milk yield 4711.7 kg was for 1st lactation cows with AB genotypes, whereas the highest milk protein content (3.35%) and fat content (4.46 %) was for BB genotypes. Analysis of the kappa-casein locus showed a prevalence of the A allele – 0.750. The genetic variant of B was characterized by a low frequency – 0.240. Moreover, the frequency of E occurred in the LB cows’ population with very low frequency – 0.010. 54.9 % of cows are homozygous with genotypes AA, and only 4.9 % are homozygous with genotypes BB. 32.8 % of individuals are heterozygous with genotypes AB, and 2.0 % are with AE. The highest milk productivity was for 1st lactation cows with AB genotypes: milk yield 4620.3 kg, milk protein content 3.39% and fat content 4.53 %. According to the results, in local Latvian brown there are only 2.9% of cows are with BB-BB genotypes, which is related to milk coagulation ability and affected cheese production yield. Acknowledgment: the investigation is supported by VPP 2014-2017 AgroBioRes Project No. 3 LIVESTOCK.Keywords: beta-lactoglobulin, cows, genotype frequencies, kappa-casein
Procedia PDF Downloads 2723532 Study of Adaptive Filtering Algorithms and the Equalization of Radio Mobile Channel
Authors: Said Elkassimi, Said Safi, B. Manaut
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This paper presented a study of three algorithms, the equalization algorithm to equalize the transmission channel with ZF and MMSE criteria, application of channel Bran A, and adaptive filtering algorithms LMS and RLS to estimate the parameters of the equalizer filter, i.e. move to the channel estimation and therefore reflect the temporal variations of the channel, and reduce the error in the transmitted signal. So far the performance of the algorithm equalizer with ZF and MMSE criteria both in the case without noise, a comparison of performance of the LMS and RLS algorithm.Keywords: adaptive filtering second equalizer, LMS, RLS Bran A, Proakis (B) MMSE, ZF
Procedia PDF Downloads 3133531 Regional Hydrological Extremes Frequency Analysis Based on Statistical and Hydrological Models
Authors: Hadush Kidane Meresa
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The hydrological extremes frequency analysis is the foundation for the hydraulic engineering design, flood protection, drought management and water resources management and planning to utilize the available water resource to meet the desired objectives of different organizations and sectors in a country. This spatial variation of the statistical characteristics of the extreme flood and drought events are key practice for regional flood and drought analysis and mitigation management. For different hydro-climate of the regions, where the data set is short, scarcity, poor quality and insufficient, the regionalization methods are applied to transfer at-site data to a region. This study aims in regional high and low flow frequency analysis for Poland River Basins. Due to high frequent occurring of hydrological extremes in the region and rapid water resources development in this basin have caused serious concerns over the flood and drought magnitude and frequencies of the river in Poland. The magnitude and frequency result of high and low flows in the basin is needed for flood and drought planning, management and protection at present and future. Hydrological homogeneous high and low flow regions are formed by the cluster analysis of site characteristics, using the hierarchical and C- mean clustering and PCA method. Statistical tests for regional homogeneity are utilized, by Discordancy and Heterogeneity measure tests. In compliance with results of the tests, the region river basin has been divided into ten homogeneous regions. In this study, frequency analysis of high and low flows using AM for high flow and 7-day minimum low flow series is conducted using six statistical distributions. The use of L-moment and LL-moment method showed a homogeneous region over entire province with Generalized logistic (GLOG), Generalized extreme value (GEV), Pearson type III (P-III), Generalized Pareto (GPAR), Weibull (WEI) and Power (PR) distributions as the regional drought and flood frequency distributions. The 95% percentile and Flow duration curves of 1, 7, 10, 30 days have been plotted for 10 stations. However, the cluster analysis performed two regions in west and east of the province where L-moment and LL-moment method demonstrated the homogeneity of the regions and GLOG and Pearson Type III (PIII) distributions as regional frequency distributions for each region, respectively. The spatial variation and regional frequency distribution of flood and drought characteristics for 10 best catchment from the whole region was selected and beside the main variable (streamflow: high and low) we used variables which are more related to physiographic and drainage characteristics for identify and delineate homogeneous pools and to derive best regression models for ungauged sites. Those are mean annual rainfall, seasonal flow, average slope, NDVI, aspect, flow length, flow direction, maximum soil moisture, elevation, and drainage order. The regional high-flow or low-flow relationship among one streamflow characteristics with (AM or 7-day mean annual low flows) some basin characteristics is developed using Generalized Linear Mixed Model (GLMM) and Generalized Least Square (GLS) regression model, providing a simple and effective method for estimation of flood and drought of desired return periods for ungauged catchments.Keywords: flood , drought, frequency, magnitude, regionalization, stochastic, ungauged, Poland
Procedia PDF Downloads 6023530 Rheological Evaluation of Wall Materials and β-Carotene Loaded Microencapsules
Authors: Gargi Ghoshal, Ashay Jain, Deepika Thakur, U. S. Shivhare, O. P. Katare
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The main objectives of this work were the rheological characterization of dispersions, emulsions at different pH used in the microcapsules preparation and the microcapsules obtain from gum arabic (A), guar gum (G), casein (C) and whey protein isolate (W) to keep β-carotene protected from degradation using the complex coacervation microencapsulation technique (CCM). The evaluation of rheological properties of dispersions, emulsions of different pH and so obtained microencapsules manifest the changes occur in the molecular structure of wall materials during the encapsulation process of β-carotene. These dispersions, emulsions of different pH and formulated microencapsules were subjected to go through various conducted experiments (flow curve test, amplitude sweep, and frequency sweep test) using controlled stress dynamic rheometer. Flow properties were evaluated as a function of apparent viscosity under steady shear rate ranging from 0.1 to 100 s-1. The frequency sweep test was conducted to determine the extent of viscosity and elasticity present in the samples at constant strain under changing angular frequency range from 0.1 to 100 rad/s at 25ºC. The dispersions and emulsion exhibited a shear thinning non-Newtonian behavior whereas microencapsules are considered as shear-thickening respectively. The apparent viscosity for dispersion, emulsions were decreased at low shear rates 20 s-1 and for microencapsules, it decreases up to ~50 s-1 besides these value, it has shown constant pattern. Oscillatory shear experiments showed a predominant viscous liquid behavior up to crossover frequencies of dispersions of C, W, A at 49.47 rad/s, 57.60 rad/s and 21.45 rad/s emulsion sample of AW at pH 5.0 it was 17.85 rad/s and GW microencapsules 61.40 rad/s respectively whereas no such crossover was found in G dispersion, emulsion with C and microencapsules still it showed more viscous behavior. Storage and loss modulus decreases with time also a shift of the crossover towards lower frequencies for A, W and C was observed respectively. However, their microencapsules showed more viscous behavior as compared to samples prior to blending.Keywords: viscosity, gums, proteins, frequency sweep test, apparent viscosity
Procedia PDF Downloads 2473529 Natural Frequency Analysis of Spinning Functionally Graded Cylindrical Shells Subjected to Thermal Loads
Authors: Esmaeil Bahmyari
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The natural frequency analysis of the functionally graded (FG) rotating cylindrical shells subjected to thermal loads is studied based on the three-dimensional elasticity theory. The temperature-dependent assumption of the material properties is graded in the thickness direction, which varies based on the simple power law distribution. The governing equations and the appropriate boundary conditions, which include the effects of initial thermal stresses, are derived employing Hamilton’s principle. The initial thermo-mechanical stresses are obtained by the thermo-elastic equilibrium equation’s solution. As an efficient and accurate numerical tool, the differential quadrature method (DQM) is adopted to solve the thermo-elastic equilibrium equations, free vibration equations and natural frequencies are obtained. The high accuracy of the method is demonstrated by comparison studies with those existing solutions in the literature. Ultimately, the parametric studies are performed to demonstrate the effects of boundary conditions, temperature rise, material graded index, the thickness-to-length and the aspect ratios for the rotating cylindrical shells on the natural frequency.Keywords: free vibration, DQM, elasticity theory, FG shell, rotating cylindrical shell
Procedia PDF Downloads 843528 Vibration of Nonhomogeneous Timoshenko Nanobeam Resting on Winkler-Pasternak Foundation
Authors: Somnath Karmakar, S. Chakraverty
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This work investigates the vibration of nonhomogeneous Timoshenko nanobeam resting on the Winkler-Pasternak foundation. Eringen’s nonlocal theory has been used to investigate small-scale effects. The Differential Quadrature method is used to obtain the frequency parameters with various classical boundary conditions. The nonhomogeneous beam model has been considered, where Young’s modulus and density of the beam material vary linearly and quadratically. Convergence of frequency parameters is also discussed. The influence of mechanical properties and scaling parameters on vibration frequencies are investigated for different boundary conditions.Keywords: Timoshenko beam, Eringen's nonlocal theory, differential quadrature method, nonhomogeneous nanobeam
Procedia PDF Downloads 1153527 Relationship between Exercise Activity with Incidence of Overweight-Obesity in Medical Students
Authors: Randy M. Fitratullah, Afriwardi, Nurhayati
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Overweight-obesity caused by exercise. The objective of this research is to analyze the relation between exercise with the incidence of overweight-obesity of medical students of medical faculty of Andalas Univesity batch 2013. This is an analytical observational research with case-control method. This research conducted in FK Unand on September-October 2015. The population of this research is medical students batch 2013. 26 samples (13 samples were case, 13 samples were control) were taken by purposive sampling technique and analysed using statistical univariate and bivariate analysis. Exercise questionnaire was used as research instruments. Based on the interview with questionnaire, anaerobic exercise was majority in case group and aerobic exercise was majority in control group. The case and control group have a rare category in exercise. Less category was majority in exercise duration of case and enough category was majority in control group. Bivariate analysis is using chi-square test with cell combining to 2x2 table, obtained p-value=0.097 in sort of exercise, p-value=1,000 in the frequency of exercise, and p-value=0,112 in duration of exercise, which means statistically unsignificant. There is no relation between exercise with the incidence of overweight-obesity of medical students of FK Unand batch 2013. For medical students suffers overweight-obesity is suggested for increase the frequency of exercise.Keywords: overweight-obesity, exercise, aerobic, anaerobic, frequency, duration
Procedia PDF Downloads 2623526 Study of Motion of Impurity Ions in Poly(Vinylidene Fluoride) from View Point of Microstructure of Polymer Solid
Authors: Yuichi Anada
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Electrical properties of polymer solid is characterized by dielectric relaxation phenomenon. Complex permittivity shows a high dependence on frequency of external stimulation in the broad frequency range from 0.1mHz to 10GHz. The complex-permittivity dispersion gives us a lot of useful information about the molecular motion of polymers and the structure of polymer aggregates. However, the large dispersion of permittivity at low frequencies due to DC conduction of impurity ions often covers the dielectric relaxation in polymer solid. In experimental investigation, many researchers have tried to remove the DC conduction experimentally or analytically for a long time. On the other hand, our laboratory chose another way of research for this problem from the point of view of a reversal in thinking. The way of our research is to use the impurity ions in the DC conduction as a probe to detect the motion of polymer molecules and to investigate the structure of polymer aggregates. In addition to the complex permittivity, the electric modulus and the conductivity relaxation time are strong tools for investigating the ionic motion in DC conduction. In a non-crystalline part of melt-crystallized polymers, free spaces with inhomogeneous size exist between crystallites. As the impurity ions exist in the non-crystalline part and move through these inhomogeneous free spaces, the motion of ions reflects the microstructure of non-crystalline part. The ionic motion of impurity ions in poly(vinylidene fluoride) (PVDF) is investigated in this study. Frequency dependence of the loss permittivity of PVDF shows a characteristic of the direct current (DC) conduction below 1 kHz of frequency at 435 K. The electric modulus-frequency curve shows a characteristic of the dispersion with the single conductivity relaxation time. Namely, it is the Debye-type dispersion. The conductivity relaxation time analyzed from this curve is 0.00003 s at 435 K. From the plot of conductivity relaxation time of PVDF together with the other polymers against permittivity, it was found that there are two group of polymers; one of the group is characterized by small conductivity relaxation time and large permittivity, and another is characterized by large conductivity relaxation time and small permittivity.Keywords: conductivity relaxation time, electric modulus, ionic motion, permittivity, poly(vinylidene fluoride), DC conduction
Procedia PDF Downloads 1703525 Parameter Selection and Monitoring for Water-Powered Percussive Drilling in Green-Fields Mineral Exploration
Authors: S. J. Addinell, T. Richard, B. Evans
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The Deep Exploration Technologies Cooperative Research Centre (DET CRC) is researching and developing a new coiled tubing based greenfields mineral exploration drilling system utilising downhole water powered percussive drill tooling. This new drilling system is aimed at significantly reducing the costs associated with identifying mineral resource deposits beneath deep, barron cover. This system has shown superior rates of penetration in water-rich hard rock formations at depths exceeding 500 meters. Several key challenges exist regarding the deployment and use of these bottom hole assemblies for mineral exploration, and this paper discusses some of the key technical challenges. This paper presents experimental results obtained from the research program during laboratory and field testing of the prototype drilling system. A study of the morphological aspects of the cuttings generated during the percussive drilling process is presented and shows a strong power law relationship for particle size distributions. Several percussive drilling parameters such as RPM, applied fluid pressure and weight on bit have been shown to influence the particle size distributions of the cuttings generated. This has direct influence on other drilling parameters such as flow loop performance, cuttings dewatering, and solids control. Real-time, accurate knowledge of percussive system operating parameters will assist the driller in maximising the efficiency of the drilling process. The applied fluid flow, fluid pressure, and rock properties are known to influence the natural oscillating frequency of the percussive hammer, but this paper also shows that drill bit design, drill bit wear and the applied weight on bit can also influence the oscillation frequency. Due to the changing drilling conditions and therefore changing operating parameters, real-time understanding of the natural operating frequency is paramount to achieving system optimisation. Several techniques to understand the oscillating frequency have been investigated and presented. With a conventional top drive drilling rig, spectral analysis of applied fluid pressure, hydraulic feed force pressure, hold back pressure and drill string vibrations have shown the presence of the operating frequency of the bottom hole tooling. Unfortunately, however, with the implementation of a coiled tubing drilling rig, implementing a positive displacement downhole motor to provide drill bit rotation, these signals are not available for interrogation at the surface and therefore another method must be considered. The investigation and analysis of ground vibrations using geophone sensors, similar to seismic-while-drilling techniques have indicated the presence of the natural oscillating frequency of the percussive hammer. This method is shown to provide a robust technique for the determination of the downhole percussive oscillation frequency when used with a coiled tubing drill rig.Keywords: cuttings characterization, drilling optimization, oscillation frequency, percussive drilling, spectral analysis
Procedia PDF Downloads 2303524 Sensing Mechanism of Nano-Toxic Ions Using Quartz Crystal Microbalance
Authors: Chanho Park, Juneseok You, Kuewhan Jang, Sungsoo Na
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Detection technique of nanotoxic materials is strongly imperative, because nano-toxic materials can harmfully influence human health and environment as their engineering applications are growing rapidly in recent years. In present work, we report the DNA immobilized quartz crystal microbalance (QCM) based sensor for detection of nano-toxic materials such as silver ions, Hg2+ etc. by using functionalization of quartz crystal with a target-specific DNA. Since the mass of a target material is comparable to that of an atom, the mass change caused by target binding to DNA on the quartz crystal is so small that it is practically difficult to detect the ions at low concentrations. In our study, we have demonstrated fast and in situ detection of nanotoxic materials using quartz crystal microbalance. We report the label-free and highly sensitive detection of silver ion for present case, which is a typical nano-toxic material by using QCM and silver-specific DNA. The detection is based on the measurement of frequency shift of Quartz crystal from constitution of the cytosine-Ag+-cytosine binding. It is shown that the silver-specific DNA measured frequency shift by QCM enables the capturing of silver ions below 100pM. The results suggest that DNA-based detection opens a new avenue for the development of a practical water-testing sensor.Keywords: nano-toxic ions, quartz crystal microbalance, frequency shift, target-specific DNA
Procedia PDF Downloads 321