Search results for: ROC Curve
687 Asymptotic Expansion of Double Oscillatory Integrals: Contribution of Non Stationary Critical Points of the Second Kind
Authors: Abdallah Benaissa
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In this paper, we consider the problem of asymptotics of double oscillatory integrals in the case of critical points of the second kind, the order of contact between the boundary and a level curve of the phase being even, the situation when the order of contact is odd will be studied in other occasions. Complete asymptotic expansions will be derived and the coefficient of the leading term will be computed in terms of the original data of the problem. A multitude of people have studied this problem using a variety of methods, but only in a special case when the order of contact is minimal: the more cited papers are a paper of Jones and Kline and an other one of Chako. These integrals are encountered in many areas of science, especially in problems of diffraction of optics.Keywords: asymptotic expansion, double oscillatory integral, critical point of the second kind, optics diffraction
Procedia PDF Downloads 344686 Bending and Shear Characteristics of Hollowcore Slab with Polystyrene Forms
Authors: Kang Kun Lee
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New I-slab system with polystyrene forms and precast concrete deck is proposed to reduce the construction period and the self-weight of the slab. This paper presents experimental works on the bending and shear of the I-slabs. Five specimens were tested. The main parameters of experiments are diameters of the holes made by polystyrene form and the thickness of slab. Structural performance of I-slab is evaluated on the basis of failure mode, load-displacement curve, and ultimate strengths. Based on the test results, it is found that the critical punching shear sections are changed as the test variables are different, hence resulting in the varied punching shear strengths. Test results indicate that the developed I-slab is very effective to increase the strength due to self-weight reduction.Keywords: hollowcore slab, section force-deformation response, precast concrete deck
Procedia PDF Downloads 377685 An investigation of Leading Edge and Trailing Edge Corrugation for Low Reynolds Number Application
Authors: Syed Hassan Raza Shah, Mohammad Mohammad Ali
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The flow over a smoothly profiled airfoil at a low Reynolds number is highly susceptible to separate even at a very low angle of attack. An investigation was made to study the effect of leading-edge and trailing-edge corrugation with the spanwise change in the ridges resulted due to the change in the chord length for an infinite wing. The wind tunnel results using NACA0018 wings revealed that leading and trailing edge corrugation did not have any benefit in terms of aerodynamic efficiency or delayed stall. The leading edge and trailing edge corrugation didn't change the lift curve slope, with the leading edge corrugation wing stalling first in the range of Reynolds number of 50,000 to 125,000.Keywords: leading and trailing edge corrugations, low reynolds number, wind tunnel testing, NACA0018
Procedia PDF Downloads 276684 Prediction of Unsaturated Permeability Functions for Clayey Soil
Authors: F. Louati, H. Trabelsi, M. Jamei
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Desiccation cracks following drainage-humidification cycles. With water loss, mainly due to evaporation, suction in the soil increases, producing volumetric shrinkage and tensile stress. When the tensile stress reaches tensile strength, the soil cracks. Desiccation cracks networks can directly control soil hydraulic properties. The aim of this study was for quantifying the hydraulic properties for examples the water retention curve, the saturated hydraulic conductivity, the unsaturated hydraulic conductivity function, the shrinkage dynamics in Tibar soil- clay soil in the Northern of Tunisia. Then a numerical simulation of unsaturated hydraulic properties for a crack network has been attempted. The finite elements code ‘CODE_BRIGHT’ can be used to follow the hydraulic distribution in cracked porous media.Keywords: desiccation, cracks, permeability, unsaturated hydraulic flow, simulation
Procedia PDF Downloads 286683 Starting Characteristic Analysis of LSPM for Pumping System Considering Demagnetization
Authors: Subrato Saha, Yun-Hyun Cho
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This paper presents the design process of a high performance 3-phase 3.7 kW 2-pole line start permanent magnet synchronous motor for pumping system. A method was proposed to study the starting torque characteristics considering line start with high inertia load. A d-q model including cage was built to study the synchronization capability. Time-stepping finite element method analysis was utilized to accurately predict the dynamic and transient performance, efficiency, starting current, speed curve and, etc. Considering the load torque of pumps during starting stage, the rotor bar was designed with minimum demagnetization of permanent magnet caused by huge starting current.Keywords: LSPM, starting analysis, demagnetization, FEA, pumping system
Procedia PDF Downloads 465682 Relation between Energy Absorption and Box Dimension of Rock Fragments under Impact Loading
Authors: Li Hung-Hui, Chen Chi-Chieh, Yang Zon-Yee
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This study aims to explore the impact energy absorption in the fragmented processes of rock samples during the split-Hopkinson-pressure-bar tests. Three kinds of rock samples including granite, marble and sandstone were tested. The impact energy absorptions were calculated according to the incident, reflected and transmitted strain wave histories measured by a oscilloscope. The degree of fragment rocks after tests was quantified by the box dimension of the fractal theory. The box dimension of rock fragments was obtained from the particle size distribution curve by the sieve analysis. The results can be concluded that: (1) the degree of rock fragments after tests can be well described by the value of box dimension; (2) with the impact energy absorption increasing, the degrees of rock fragments are varied from the very large fragments to very small fragments, and the corresponding box dimension varies from 2.9 to 1.2.Keywords: SHPB test, energy absorption, rock fragments, impact loading, box dimension
Procedia PDF Downloads 437681 Development and Implementation of Curvature Dependent Force Correction Algorithm for the Planning of Forced Controlled Robotic Grinding
Authors: Aiman Alshare, Sahar Qaadan
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A curvature dependent force correction algorithm for planning force controlled grinding process with off-line programming flexibility is designed for ABB industrial robot, in order to avoid the manual interface during the process. The machining path utilizes a spline curve fit that is constructed from the CAD data of the workpiece. The fitted spline has a continuity of the second order to assure path smoothness. The implemented algorithm computes uniform forces normal to the grinding surface of the workpiece, by constructing a curvature path in the spatial coordinates using the spline method.Keywords: ABB industrial robot, grinding process, offline programming, CAD data extraction, force correction algorithm
Procedia PDF Downloads 353680 Optimization of Hydrogel Conductive Nanocomposite as Solar Cell
Authors: Shimaa M. Elsaeed, Reem K. Farag, Ibrahim M. Nassar
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Hydrogel conductive polymer nanocomposite fabricated via in-situ polymerization of polyaniline (PANI) inside thermosensitive hydrogels based on hydroxy ethyl meth acrylate (HEMA) copolymer with 2-acrylamido-2-methyl propane sulfonic acid (AMPS). SEM micrographs show the nanometric size of the conductive material (polyaniline, PANI) dispersed in the hydrogel matrix. The swelling parameters of hydrogel are measured. The incorporation of PANI improves the mechanical properties and swelling up to 30,000% without breaking. X-ray diffraction shows that typical polyaniline crystallization is formed in composite, which is advantageous to increase the electrical conductivity of the composite hydrogel. Open-circuit voltage (I-V) curve fill factor of the highest photo-conversion efficiency and enhanced to use in solar cell.Keywords: hydrogel, solar cell, conductive polymer, nanocomposite
Procedia PDF Downloads 392679 Clinical Validation of C-PDR Methodology for Accurate Non-Invasive Detection of Helicobacter pylori Infection
Authors: Suman Som, Abhijit Maity, Sunil B. Daschakraborty, Sujit Chaudhuri, Manik Pradhan
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Background: Helicobacter pylori is a common and important human pathogen and the primary cause of peptic ulcer disease and gastric cancer. Currently H. pylori infection is detected by both invasive and non-invasive way but the diagnostic accuracy is not up to the mark. Aim: To set up an optimal diagnostic cut-off value of 13C-Urea Breath Test to detect H. pylori infection and evaluate a novel c-PDR methodology to overcome of inconclusive grey zone. Materials and Methods: All 83 subjects first underwent upper-gastrointestinal endoscopy followed by rapid urease test and histopathology and depending on these results; we classified 49 subjects as H. pylori positive and 34 negative. After an overnight, fast patients are taken 4 gm of citric acid in 200 ml water solution and 10 minute after ingestion of the test meal, a baseline exhaled breath sample was collected. Thereafter an oral dose of 75 mg 13C-Urea dissolved in 50 ml water was given and breath samples were collected upto 90 minute for 15 minute intervals and analysed by laser based high precisional cavity enhanced spectroscopy. Results: We studied the excretion kinetics of 13C isotope enrichment (expressed as δDOB13C ‰) of exhaled breath samples and found maximum enrichment around 30 minute of H. pylori positive patients, it is due to the acid mediated stimulated urease enzyme activity and maximum acidification happened within 30 minute but no such significant isotopic enrichment observed for H. pylori negative individuals. Using Receiver Operating Characteristic (ROC) curve an optimal diagnostic cut-off value, δDOB13C ‰ = 3.14 was determined at 30 minute exhibiting 89.16% accuracy. Now to overcome grey zone problem we explore percentage dose of 13C recovered per hour, i.e. 13C-PDR (%/hr) and cumulative percentage dose of 13C recovered, i.e. c-PDR (%) in exhaled breath samples for the present 13C-UBT. We further explored the diagnostic accuracy of 13C-UBT by constructing ROC curve using c-PDR (%) values and an optimal cut-off value was estimated to be c-PDR = 1.47 (%) at 60 minute, exhibiting 100 % diagnostic sensitivity , 100 % specificity and 100 % accuracy of 13C-UBT for detection of H. pylori infection. We also elucidate the gastric emptying process of present 13C-UBT for H. pylori positive patients. The maximal emptying rate found at 36 minute and half empting time of present 13C-UBT was found at 45 minute. Conclusions: The present study exhibiting the importance of c-PDR methodology to overcome of grey zone problem in 13C-UBT for accurate determination of infection without any risk of diagnostic errors and making it sufficiently robust and novel method for an accurate and fast non-invasive diagnosis of H. pylori infection for large scale screening purposes.Keywords: 13C-Urea breath test, c-PDR methodology, grey zone, Helicobacter pylori
Procedia PDF Downloads 297678 The Role of Self-Confidence, Adversity Quotient, and Self-Efficacy Critical Thinking: Path Model
Authors: Bayu Dwi Cahyo, Ekohariadi, Theodorus Wiyanto Wibowo, I. G. P. Asto Budithahjanto, Eppy Yundra
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The objective of this study is to examine the effects of self-confidence, adversity quotient, and self-efficacy variables on critical thinking. This research's participants are 137 cadets of Aviation Polytechnics of Surabaya with the sampling technique that was purposive sampling. In this study, the data collection method used a questionnaire with Linkert-scale and distributed or given to respondents by the specified number of samples. The SPSS AMOS v23 was used to test a number of a priori multivariate growth curve models and examining relationships between the variables via path analysis. The result of path analysis was (χ² = 88.463, df= 71, χ² /df= 1.246, GFI= .914, CFI= .988, P= .079, AGFI= .873, TLI= .985, RMSEA= .043). According to the analysis, there is a positive and significant relationship between self-confidence, adversity quotient, and self-efficacy variables on critical thinking.Keywords: self-confidence, adversity quotient, self-efficacy variables, critical thinking
Procedia PDF Downloads 138677 Preliminary Study of Standardization and Validation of Micronuclei Technique to Assess the DNA Damages Cause for the X-Rays
Authors: L. J. Díaz, M. A. Hernández, A. K. Molina, A. Bermúdez, C. Crane, V. M. Pabón
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One of the most important biological indicators that show the exposure to the radiation is the micronuclei (MN). This technique is using to determinate the radiation effects in blood cultures as a biological control and a complement to the physics dosimetry. In Colombia the necessity to apply this analysis has emerged due to the current biological indicator most used is the chromosomal aberrations (CA), that is why it is essential the MN technique’s standardization and validation to have enough tools to improve the radioprotection topic in the country. Besides, this technique will be applied on the construction of a dose-response curve, that allow measure an approximately dose to irradiated people according to MN frequency found. Inside the steps that carried out to accomplish the standardization and validation is the statistic analysis from the lectures of “in vitro” peripheral blood cultures with different analysts, also it was determinate the best culture medium and conditions for the MN can be detected easily.Keywords: micronuclei, radioprotection, standardization, validation
Procedia PDF Downloads 487676 Stress Solitary Waves Generated by a Second-Order Polynomial Constitutive Equation
Authors: Tsun-Hui Huang, Shyue-Cheng Yang, Chiou-Fen Shieha
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In this paper, a nonlinear constitutive law and a curve fitting, two relationships between the stress-strain and the shear stress-strain for sandstone material were used to obtain a second-order polynomial constitutive equation. Based on the established polynomial constitutive equations and Newton’s second law, a mathematical model of the non-homogeneous nonlinear wave equation under an external pressure was derived. The external pressure can be assumed as an impulse function to simulate a real earthquake source. A displacement response under nonlinear two-dimensional wave equation was determined by a numerical method and computer-aided software. The results show that a suit pressure in the sandstone generates the phenomenon of stress solitary waves.Keywords: polynomial constitutive equation, solitary, stress solitary waves, nonlinear constitutive law
Procedia PDF Downloads 486675 DNA Intercalating Alkaloids Isolated from Chelidonium majus (Papaveraceae)
Authors: Mohamed Tamer, Wink Michael
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DNA intercalating agents increase the stability of DNA which can be demonstrated by measuring the melting temperature Tm. Tm can be determined in a spectrophotometer in which the cell temperature is increased gradually. The resulting absorption data comes as a sigmoidal curve from which melting temperature can be determined when half of the DNA has denatured. The current study aims to assess DNA intercalating activities of four pure bioactive isoquinoline alkaloids: sanguinarine, berberine, allocryptopine, and chelerythrine which were isolated from Chelidonium majus (Papaveraceae) by repeated silica gel column chromatography, recrystallization and preparative TLC. The isolated compounds were identified by comparing their physical properties and mass spectra with those of the published data. The results showed that sanguiarine is the most active intercalating agent with Tm value of 83.55 ± 0.49 followed by berberine, chelerythrine, and allocryptopine with Tm values 62.58 ± 0.47, 51.38 ± 0.37 and 50.94 ± 0.65, respectively, relative to 49.78 ± 1.05 of bacteriophage DNA alone and 86.09 ± 0.5 for ethidium bromide as a positive control.Keywords: alkaloids, Chelidonium majus, DNA intercalation, Tm
Procedia PDF Downloads 490674 Finding the Free Stream Velocity Using Flow Generated Sound
Authors: Saeed Hosseini, Ali Reza Tahavvor
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Sound processing is one the subjects that newly attracts a lot of researchers. It is efficient and usually less expensive than other methods. In this paper the flow generated sound is used to estimate the flow speed of free flows. Many sound samples are gathered. After analyzing the data, a parameter named wave power is chosen. For all samples, the wave power is calculated and averaged for each flow speed. A curve is fitted to the averaged data and a correlation between the wave power and flow speed is founded. Test data are used to validate the method and errors for all test data were under 10 percent. The speed of the flow can be estimated by calculating the wave power of the flow generated sound and using the proposed correlation.Keywords: the flow generated sound, free stream, sound processing, speed, wave power
Procedia PDF Downloads 405673 Results of Twenty Years of Laparoscopic Hernia Repair Surgeries
Authors: Arun Prasad
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Introduction: Laparoscopic surgery of hernia started in early 1990 and has had a mixed acceptance across the world, unlike laparoscopic cholecystectomy that has become a gold standard. Laparoscopic hernia repair claims to have less pain, less recurrence, and less wound infection compared to open hernia repair leading to early recovery and return to work. Materials and Methods: Laparoscopic hernia repair has been done in 2100 patients from 1995 till now with a follow-up data of 1350 patients. Data was analysed for results and satisfaction. Results: There is a recurrence rate of 0.1%. Early complications include bleeding, trocar injury and nerve pain. Late complications were rare. Conclusion: Laparoscopic inguinal hernia repair has a steep learning curve but after that the results and patient satisfaction are very good. It should be the procedure of choice in all bilateral and recurrent hernias.Keywords: laparoscopy, hernia, mesh, surgery
Procedia PDF Downloads 246672 Liquid-Liquid Equilibrium Study in Solvent Extraction of o-Cresol from Coal Tar
Authors: Dewi Selvia Fardhyanti, Astrilia Damayanti
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Coal tar is a liquid by-product of the process of coal gasification and carbonation, also in some industries such as steel, power plant, cement, and others. This liquid oil mixture contains various kinds of useful compounds such as aromatic compounds and phenolic compounds. These compounds are widely used as raw material for insecticides, dyes, medicines, perfumes, coloring matters, and many others. This research investigates thermodynamic modelling of liquid-liquid equilibria (LLE) in solvent extraction of o-Cresol from the coal tar. The equilibria are modeled by ternary components of Wohl, Van Laar, and Three-Suffix Margules models. The values of the parameters involved are obtained by curve-fitting to the experimental data. Based on the comparison between calculated and experimental data, it turns out that among the three models studied, the Three-Suffix Margules seems to be the best to predict the LLE of o-Cresol for those system.Keywords: coal tar, o-Cresol, Wohl, Van Laar, three-suffix margules
Procedia PDF Downloads 270671 New Dynamic Constitutive Model for OFHC Copper Film
Authors: Jin Sung Kim, Hoon Huh
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The material properties of OFHC copper film was investigated with the High-Speed Material Micro Testing Machine (HSMMTM) at the high strain rates. The rate-dependent stress-strain curves from the experiment and the Johnson-Cook curve fitting showed large discrepancies as the plastic strain increases since the constitutive model implies no rate-dependent strain hardening effect. A new constitutive model was proposed in consideration of rate-dependent strain hardening effect. The strain rate hardening term in the new constitutive model consists of the strain rate sensitivity coefficients of the yield strength and strain hardening.Keywords: rate dependent material properties, dynamic constitutive model, OFHC copper film, strain rate
Procedia PDF Downloads 480670 Software Quality Assurance in Network Security using Cryptographic Techniques
Authors: Sidra Shabbir, Ayesha Manzoor, Mehreen Sirshar
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The use of the network communication has imposed serious threats to the security of assets over the network. Network security is getting more prone to active and passive attacks which may result in serious consequences to data integrity, confidentiality and availability. Various cryptographic techniques have been proposed in the past few years to combat with the concerned problem by ensuring quality but in order to have a fully secured network; a framework of new cryptosystem was needed. This paper discusses certain cryptographic techniques which have shown far better improvement in the network security with enhanced quality assurance. The scope of this research paper is to cover the security pitfalls in the current systems and their possible solutions based on the new cryptosystems. The development of new cryptosystem framework has paved a new way to the widespread network communications with enhanced quality in network security.Keywords: cryptography, network security, encryption, decryption, integrity, confidentiality, security algorithms, elliptic curve cryptography
Procedia PDF Downloads 726669 Comparison of Prognostic Models in Different Scenarios of Shoreline Position on Ponta Negra Beach in Northeastern Brazil
Authors: Débora V. Busman, Venerando E. Amaro, Mattheus da C. Prudêncio
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Prognostic studies of the shoreline are of utmost importance for Ponta Negra Beach, located in Natal, Northeastern Brazil, where the infrastructure recently built along the shoreline is severely affected by flooding and erosion. This study compares shoreline predictions using three linear regression methods (LMS, LRR and WLR) and tries to discern the best method for different shoreline position scenarios. The methods have shown erosion on the beach in each of the scenarios tested, even in less intense dynamic conditions. The WLA_A with confidence interval of 95% was the well-adjusted model and calculated a retreat of -1.25 m/yr to -2.0 m/yr in hot spot areas. The change of the shoreline on Ponta Negra Beach can be measured as a negative exponential curve. Analysis of these methods has shown a correlation with the morphodynamic stage of the beach.Keywords: coastal erosion, prognostic model, DSAS, environmental safety
Procedia PDF Downloads 323668 Finite Element Modeling and Analysis of Reinforced Concrete Coupled Shear Walls Strengthened with Externally Bonded Carbon Fiber Reinforced Polymer Composites
Authors: Sara Honarparast, Omar Chaallal
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Reinforced concrete (RC) coupled shear walls (CSWs) are very effective structural systems in resisting lateral loads due to winds and earthquakes and are particularly used in medium- to high-rise RC buildings. However, most of existing old RC structures were designed for gravity loads or lateral loads well below the loads specified in the current modern seismic international codes. These structures may behave in non-ductile manner due to poorly designed joints, insufficient shear reinforcement and inadequate anchorage length of the reinforcing bars. This has been the main impetus to investigate an appropriate strengthening method to address or attenuate the deficiencies of these structures. The objective of this paper is to twofold: (i) evaluate the seismic performance of existing reinforced concrete coupled shear walls under reversed cyclic loading; and (ii) investigate the seismic performance of RC CSWs strengthened with externally bonded (EB) carbon fiber reinforced polymer (CFRP) sheets. To this end, two CSWs were considered as follows: (a) the first one is representative of old CSWs and therefore was designed according to the 1941 National Building Code of Canada (NBCC, 1941) with conventionally reinforced coupling beams; and (b) the second one, representative of new CSWs, was designed according to modern NBCC 2015 and CSA/A23.3 2014 requirements with diagonally reinforced coupling beam. Both CSWs were simulated using ANSYS software. Nonlinear behavior of concrete is modeled using multilinear isotropic hardening through a multilinear stress strain curve. The elastic-perfectly plastic stress-strain curve is used to simulate the steel material. Bond stress–slip is modeled between concrete and steel reinforcement in conventional coupling beam rather than considering perfect bond to better represent the slip of the steel bars observed in the coupling beams of these CSWs. The old-designed CSW was strengthened using CFRP sheets bonded to the concrete substrate and the interface was modeled using an adhesive layer. The behavior of CFRP material is considered linear elastic up to failure. After simulating the loading and boundary conditions, the specimens are analyzed under reversed cyclic loading. The comparison of results obtained for the two unstrengthened CSWs and the one retrofitted with EB CFRP sheets reveals that the strengthening method improves the seismic performance in terms of strength, ductility, and energy dissipation capacity.Keywords: carbon fiber reinforced polymer, coupled shear wall, coupling beam, finite element analysis, modern code, old code, strengthening
Procedia PDF Downloads 189667 Low Cost Inertial Sensors Modeling Using Allan Variance
Authors: A. A. Hussen, I. N. Jleta
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Micro-electromechanical system (MEMS) accelerometers and gyroscopes are suitable for the inertial navigation system (INS) of many applications due to the low price, small dimensions and light weight. The main disadvantage in a comparison with classic sensors is a worse long term stability. The estimation accuracy is mostly affected by the time-dependent growth of inertial sensor errors, especially the stochastic errors. In order to eliminate negative effect of these random errors, they must be accurately modeled. Where the key is the successful implementation that depends on how well the noise statistics of the inertial sensors is selected. In this paper, the Allan variance technique will be used in modeling the stochastic errors of the inertial sensors. By performing a simple operation on the entire length of data, a characteristic curve is obtained whose inspection provides a systematic characterization of various random errors contained in the inertial-sensor output data.Keywords: Allan variance, accelerometer, gyroscope, stochastic errors
Procedia PDF Downloads 424666 Heart-Rate Resistance Electrocardiogram Identification Based on Slope-Oriented Neural Networks
Authors: Tsu-Wang Shen, Shan-Chun Chang, Chih-Hsien Wang, Te-Chao Fang
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For electrocardiogram (ECG) biometrics system, it is a tedious process to pre-install user’s high-intensity heart rate (HR) templates in ECG biometric systems. Based on only resting enrollment templates, it is a challenge to identify human by using ECG with the high-intensity HR caused from exercises and stress. This research provides a heartbeat segment method with slope-oriented neural networks against the ECG morphology changes due to high intensity HRs. The method has overall system accuracy at 97.73% which includes six levels of HR intensities. A cumulative match characteristic curve is also used to compare with other traditional ECG biometric methods.Keywords: high-intensity heart rate, heart rate resistant, ECG human identification, decision based artificial neural network
Procedia PDF Downloads 420665 Useful Lifetime Prediction of Chevron Rubber Spring for Railway Vehicle
Authors: Chang Su Woo, Hyun Sung Park
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Useful lifetime evaluation of chevron rubber spring was very important in design procedure to assure the safety and reliability. It is, therefore, necessary to establish a suitable criterion for the replacement period of chevron rubber spring. In this study, we performed characteristic analysis and useful lifetime prediction of chevron rubber spring. Rubber material coefficient was obtained by curve fittings of uni-axial tension, equi bi-axial tension and pure shear test. Computer simulation was executed to predict and evaluate the load capacity and stiffness for chevron rubber spring. In order to useful lifetime prediction of rubber material, we carried out the compression set with heat aging test in an oven at the temperature ranging from 50°C to 100°C during a period 180 days. By using the Arrhenius plot, several useful lifetime prediction equations for rubber material was proposed.Keywords: chevron rubber spring, material coefficient, finite element analysis, useful lifetime prediction
Procedia PDF Downloads 560664 Pull-Out Behavior of Mechanical Anchor Bolts by Cyclic Loading
Authors: Yoshinori Kitsutaka, Kusumi Shingo, Matsuzawa Koichi, Kunieda Yoichiro, Yagisawa Yasuei
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In this study, the pull-out properties of various mechanical anchor bolts embedded in concrete were investigated. Five kinds of mechanical anchor bolts were selected which were ordinarily used for concrete anchoring. Tensile tests for mechanical anchor bolts embedded in φ300mm x 100mm size concrete were conducted to measure the load - load displacement curves. The loading conditions were a monotonous loading and a repeating loading. The fracture energy for each mechanical anchor bolts was estimated by the analysis of consumed energy calculated by the load - load displacement curve. The effect of the types of mechanical anchor bolts on the pull-out properties of concrete subjected in monotonous loading and a repeating loading was cleared.Keywords: concrete, cyclic loading, mechanical anchor bolt, pull-out strength
Procedia PDF Downloads 253663 Comparison of Various Response Spectrum of Nuclear Power Plant at Chashma Site
Authors: J. Iqbal, A. Shah, M. Zeeshan
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UBC-97, USNRC, chines origin code GB50011-2011 and site response spectrum was used to make comparison between them for Chashma site and most conservative one was selected and the USNRC was the most conservative one. The dynamic analysis of CHASNUPP-2 containment building was performed using SAP-2000 for dead load, live load (crane), pre stressed loads, wind load, temperature load, accidental pressure during LOCA, earthquake loads and the conservative response spectrum. After applying selected response spectrum on model, detail comparison was made against area of steal calculated from the analysis and the actually provided. Then prepared curve of area of steal vs. g value which shows that if the particular site was design on that spectrum that much steel needed for structural integrity.Keywords: response spectrum, USNRC, LOCA, area of steel, structure integrity
Procedia PDF Downloads 672662 Application of Genetic Programming for Evolution of Glass-Forming Ability Parameter
Authors: Manwendra Kumar Tripathi, Subhas Ganguly
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A few glass forming ability expressions in terms of characteristic temperatures have been proposed in the literature. Attempts have been made to correlate the expression with the critical diameter of the bulk metallic glass composition. However, with the advent of new alloys, many exceptions have been noted and reported. In the present approach, a genetic programming based code which generates an expression in terms of input variables, i.e., three characteristic temperatures viz. glass transition temperature (Tg), onset crystallization temperature (Tx) and offset temperature of melting (Tl) with maximum correlation with a critical diameter (Dmax). The expression evolved shows improved correlation with the critical diameter. In addition, the expression can be explained on the basis of time-temperature transformation curve.Keywords: glass forming ability, genetic programming, bulk metallic glass, critical diameter
Procedia PDF Downloads 324661 Data about Loggerhead Sea Turtle (Caretta caretta) and Green Turtle (Chelonia mydas) in Vlora Bay, Albania
Authors: Enerit Sacdanaku, Idriz Haxhiu
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This study was conducted in the area of Vlora Bay, Albania. Data about Sea Turtles Caretta caretta and Chelonia mydas, belonging to two periods of time (1984–1991; 2008–2014) are given. All data gathered were analyzed using recent methodologies. For all turtles captured (as by catch), the Curve Carapace Length (CCL) and Curved Carapace Width (CCW) were measured. These data were statistically analyzed, where the mean was 67.11 cm for CCL and 57.57 cm for CCW of all individuals studied (n=13). All untagged individuals of marine turtles were tagged using metallic tags (Stockbrand’s titanium tag) with an Albanian address. Sex was determined and resulted that 45.4% of individuals were females, 27.3% males and 27.3% juveniles. All turtles were studied for the presence of the epibionts. The area of Vlora Bay is used from marine turtles (Caretta caretta) as a migratory corridor to pass from the Mediterranean to the northern part of the Adriatic Sea.Keywords: Caretta caretta, Chelonia mydas, CCL, CCW, tagging, Vlora Bay
Procedia PDF Downloads 173660 Thermodynamic Modelling of Liquid-Liquid Equilibria (LLE) in the Separation of p-Cresol from the Coal Tar by Solvent Extraction
Authors: D. S. Fardhyanti, Megawati, W. B. Sediawan
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Coal tar is a liquid by-product of the process of coal gasification and carbonation. This liquid oil mixture contains various kinds of useful compounds such as aromatic compounds and phenolic compounds. These compounds are widely used as raw material for insecticides, dyes, medicines, perfumes, coloring matters, and many others. This research investigates thermodynamic modelling of liquid-liquid equilibria (LLE) in the separation of phenol from the coal tar by solvent extraction. The equilibria are modeled by ternary components of Wohl, Van Laar, and Three-Suffix Margules models. The values of the parameters involved are obtained by curve-fitting to the experimental data. Based on the comparison between calculated and experimental data, it turns out that among the three models studied, the Three-Suffix Margules seems to be the best to predict the LLE of p-Cresol mixtures for those system.Keywords: coal tar, phenol, Wohl, Van Laar, Three-Suffix Margules
Procedia PDF Downloads 251659 Modelling Railway Noise Over Large Areas, Assisted by GIS
Authors: Conrad Weber
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The modelling of railway noise over large projects areas can be very time consuming in terms of preparing the noise models and calculation time. An open-source GIS program has been utilised to assist with the modelling of operational noise levels for 675km of railway corridor. A range of GIS algorithms were utilised to break up the noise model area into manageable calculation sizes. GIS was utilised to prepare and filter a range of noise modelling inputs, including building files, land uses and ground terrain. A spreadsheet was utilised to manage the accuracy of key input parameters, including train speeds, train types, curve corrections, bridge corrections and engine notch settings. GIS was utilised to present the final noise modelling results. This paper explains the noise modelling process and how the spreadsheet and GIS were utilised to accurately model this massive project efficiently.Keywords: noise, modeling, GIS, rail
Procedia PDF Downloads 114658 Complete Enumeration Approach for Calculation of Residual Entropy for Diluted Spin Ice
Authors: Yuriy A. Shevchenko, Konstantin V. Nefedev
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We consider the antiferromagnetic systems of Ising spins located at the sites of the hexagonal, triangular and pyrochlore lattices. Such systems can be diluted to a certain concentration level by randomly replacing the magnetic spins with nonmagnetic ones. Quite recently we studied density of states (DOS) was calculated by the Wang-Landau method. Based on the obtained data, we calculated the dependence of the residual entropy (entropy at a temperature tending to zero) on the dilution concentration for quite large systems (more than 2000 spins). In the current study, we obtained the same data for small systems (less than 20 spins) by a complete search of all possible magnetic configurations and compared the result with the result for large systems. The shape of the curve remains unchanged in both cases, but the specific values of the residual entropy are different because of the finite size effect.Keywords: entropy, pyrochlore, spin ice, Wang-Landau algorithm
Procedia PDF Downloads 257