Miracle-dz/UniFAR-FTUs huggingface dataset:
Integration Of Finite Element Software In Undergraduate Engineering Courses

Computer-based engineering analysis tools have become more powerful and userfriendly in recent years. Most commercial software packages are now available for use on standard Windows-based PC’s. Aided by increases in readily available computing power, finite element analysis (FEA) codes, in particular, have gained widespread use. FEA is now considered by many to be a standard tool for engineers. This paper outlines the incorporation of assignments based on the commercial FEA code, ANSYS, into standard lecture courses in mechanical and chemical engineering. It is now typical, at least in mechanical engineering (ME) curricula, to include course(s) specific to FEA, and these courses often include use of commercial FEA codes. Now that these codes have become more user-friendly and their plotting and animating capabilities have become more sophisticated, they can be used effectively to illustrate concepts encountered in a range of undergraduate engineering courses. The examples included in this paper are from three courses: heat transfer, fluid mechanics, and mechanical vibrations. The FEA assignments are used to complement core lecture material in the courses. They are designed so that no previous ANSYS experience, or FEA background, is required. In addition to aiding students in understanding the basic theory related to specific courses, incorporation of the software in a range of courses should increase students’ awareness of the broad applicability of general-purpose FEA codes, and the advantages of using these codes as tools. It seems reasonable to expect that engineers in the 21 century will need to be comfortable with the use of FEA software and other types of analysis software in order to be effective in the workplace. Limiting student use of FEA codes to only FEA courses may not provide sufficient emphasis to the idea that these codes can be used to an engineer’s advantage in many scenarios.
Polarisation dynamics in ferroelectric materials

Ferroelectric materials have established themselves as indispensable in key applications such as piezoelectric transducers and energy storage devices. While the use of ferroelectrics in these fields dates back more than 50 years, little progress has been made to extend applications of ferroelectrics into new fields. To a large extend the observed slow progress is not caused by a lack of potential applications, but to by the inherent complexity associated with a structural phase transition, combined with strong coupling of polarisation, strain and temperature, and the strong modification of the phenomena by material defects. This thesis takes a look at prospective applications in energy storage for pulse power applications, solid state cooling and non-volatile random access memory and identifies key issues that need to be resolved. The thesis delivers time-domain based approaches to determine ferroelectric switching behaviour of bulk materials and thin films down to sub-ns time scales. The approach permitted study of how information written to a ferroelectric memory decays as a result of multiple non-destructive read operations. Furthermore simultaneous direct measurements of temperature and ferroelectric switching established a direct link between the retarded switching phenomenon observed in ferroelectrics and temperature changes brought by the electrocaloric effect. By comparison with analytical models and numerical simulation a large localised temperature change on the scale of individual domains is postulated. It implies a much larger coupling between switching and local temperature than has been previously considered. In extension of the model the frequency dependence of polarisation fatigue under bipolar conditions is explained by the occurrence of large temperature gradients in the material.
Evaluation of fenugreek (Trigonella foenum-graecum L.) genotypes for growth and seed yield

An effort was made to find out the promising genotypes suitable for Bengaluru with 25 genotypes of fenugreek with diverse geographical origins during kharif 2009 in randomized block design with two replications. The mean data were subjected to statistical analysis. All the genotypes varied significantly with respect to growth and yield parameters. The genotype CO-1 performed well with respect to growth parameters, whereas Chikkaballapur Local for yield parameters at different stages of crop growth. The genotypic and phenotypic coefficients of variation were maximum for the number of branches per plant at 30 DAS, number of branches and plant spread at harvest. Heritability and genetic advance estimates were high for all the traits except for plant height, number of branches and plant spread at 30 DAS, pod length and harvest index. Seed yield was found to be positively and significantly correlated with shelling percentage, number of pods per plant, 1000-seed weight, number of seeds per pod and plant spread at harvest. Path analysis revealed that number of pods per plant, shelling percentage, harvest index, number of branches and plant height at harvest exhibited high positive direct effect on seed yield. Some of the genotypes have been identified as desirable for growth and yield attributes which can be used in the breeding programme for further improvement.
Some Existence Theorems for Semilinear Hyperbolic Systems in One Space Variable.

Abstract : We study semilinear hyperbolic systems with quadratic nonlinearities which originate in the kinetic theory of gas as a simplification of Boltzmann's equation. Local existence is well known for these equations and the main problem is to prove global existence for nonnegative bounded data. Except for the unrealistic case where a bounded invariant region exists, no result of this type is known in three space dimensions. As in all preceding results, based on the work of Mimura-Nishida and Crandall-Tartar, we restrict ourselves to one space dimension. We show global existence for a quite general class of systems and under some special condition (S) we obtain information on the asymptotic behaviour and on scattering when the data have small L1 norm. The new idea lies in the introduction of some functional spaces where some products can be defined; this enables us to define an appropriate notion of solution in L1 and then use it to obtain local and global existence for data in L1 (R).
Low background techniques and experimental challenges for Borexino and its nylon vessels

Neutrino physics has seen exciting developments over the past five years, following the experimental evidence of their oscillations in the atmospheric and solar sectors; precise measurements of neutrino properties play a crucial role in understanding fundamental interactions and physics at the cosmological scale. Borexino is an experiment for low energy (< 1 MeV) solar neutrino spectroscopy approaching completion at the underground Gran Sasso laboratories in Italy. It is specifically designed to measure in real time the flux of mono-energetic 7Be neutrinos produced by fusion reactions in the Sun. Its 300-ton liquid scintillator target is contained in an 8.5 meter diameter nylon inner vessel (IV) and is surrounded by 1000 tons of buffer fluid. A second, 11.5 meter diameter concentric nylon outer vessel (OV) around the IV serves as a barrier for radon emanated at the periphery of the detector. Borexino requires unprecedented low levels of radioactive impurities to be a success (∼ 1 background event/day in the central 100-tons of scintillator). The IV, which is in direct contact with the scintillator, also has to meet extremely stringent radioactive and cleanliness requirements. Intrinsic levels ∼ 10−12 g/g for U and Th and ∼ 10−8 g/g for K are needed. A maximum ∼ 5 mg of “dust” and ∼ 5 × 10−5 Bq 210Pb activity deposited (from radon in the air) on its surface can be tolerated. The vessels, assembled in a clean room in Princeton, made of a 125 micron-thick membrane, need to be leak tight at the 10−2 cc/s and 1 cc/s level for the IV and OV respectively, and have to withstand mechanical stresses due to density differences and temperature gradients between the fluids they contain. Their requirements and assembly process are presented in detail. An upper limit on the inner vessel leak rate of 10−3 cc/s was measured. The performance of a matrix of light sources, placed on both vessels for monitoring its shape with digital cameras, is demonstrated. A measurement of the relative densities of the scintillator and buffer solutions to better than 1 part in 104 is also discussed. The problem of surface contamination by radon in the air is extensively addressed,
Peripheral chemoreceptor (PC) inputs contribute to the development of high blood pressure in spontaneously hypertensive rats (SHR)

The PC reflex is enhanced in subjects with established hypertension. Moreover, carotid body (CB) glomus cells from juvenile SHR show hypersensivity to acidosis even before the onset of hypertension, and pre‐hypertensive SHRs (PH‐SHR) display enhanced sympathoexcitatory responses to PC stimulation (Circ Res 106: 536, 2010). We hypothesized that heightened PC activity in PH‐SHR contributes to the development of hypertension in later life. CBs were excised bilaterally in PH‐SHR (n=7) and Wistar (n=7) rats at 4.5 weeks of age. Mean arterial pressure (MAP) was measured in conscious freely moving animals (see Brain Res 1119:165, 2006) and compared to age matched sham operated PH‐SHR (n=7) and Wistars (n=7). One day after the surgery CB‐ablated animals did not respond to hypoxia (10% O2) confirming full excision. Adult CB‐excised SHRs (12 weeks) showed lower MAP than sham operated SHRs (124±2 vs 145±6 mmHg, P<0.05). CB‐ablated SHR's MAP remained significantly higher than both Wistar controls (105±5 mmHg, P<0.05). The data obtained indicate that CB excision in juvenile PH‐SHR reduces the degree of hypertension in adult life. We suggest that CB hypersensitivity contributes to the development of high sympathetic drive and concomitant hypertension in the SHR.
Determination of mechanical properties of artificial turf football pitches according to structural components

Structural components of artificial turf football pitches have been improved in the last decade. The aim of this study was to explore the influence of structural components on the in situ mechanical behaviour of third-generation artificial turf football pitches. In total, 21 pitches were analysed according to the specified FIFA procedures. The results revealed that each of the pitches complies with the requirements of FIFA regulations. Pile length sample, stabilising bulk density, tuft/m2 and sub-base material all demonstrated a significant influence on the mechanical properties of the surface (p < 0.05). Finally, the selected structural parameters explained 77.9%, 59.8% and 54.3% of variance in rotational traction, vertical deformation and force reduction, respectively. These results show the importance of the selection of the structural components in the design of artificial turf football pitches.
High Density Power Conversion Electronics Enabled by GaN-Based Modular Topologies

This dissertation explores the use of modular multilevel converter (MMC) architectures, coupled with wide-bandgap semiconductors, to achieve high power-density in power electronics converters. At the converter level, the capabilities of the modular multilevel converter are investigated for their use in low voltage, low power, DC-DC and DC-AC applications. This investigation shows that the use of modular multilevel architectures enables low voltage Gallium Nitride high electron mobility transistors (GaN HEMTs) to be used in applications for which their voltage thresholds are not typically suited. This results in lightweight, compact, conversion systems. GaN HEMTs have been shown to provide a low loss, low volume alternative to Silicon transistors for power conversion, but require several enabling technologies to make them ideally suited to high-density converters. This work therefore presents two enabling technologies for GaN-based conversion circuits. First, a technique is developed that optimizes the gate resistance for driving GaN HEMTs in order to ensure safe, rapid device turn on. Next, the development of planar magnetic transformers is discussed, with a focus on high-frequency converter operation. For each of these technologies mathematical analysis, circuit simulation, and hardware development are performed and compared to ensure proper functionality. Taking advantage of those two enabling technologies, two converter architectures based on the MMC structure are developed. First, a DC-AC MMC is presented, taking advantage of GaN HEMTs and minimal filtering requirements to achieve high power density in low voltage systems. Next, that topology is extended and a novel DC-DC converter based on two coupled DC-AC MMCs is presented. Both systems are described mathematically, simulated, and developed as hardware prototypes to prove functionality. While both converter systems are relevant for applications in DC microgrids, the DC-AC converter will be specifically investigated for its application as a variable speed drive in naval power systems. Likewise, the DC-DC MMC will be shown to provide new solutions for high voltage spacecraft power systems. Based on the work presented in this dissertation, engineers will be presented with alternatives to traditional methods of achieving high density in power conversion systems. By coupling the low filtering requirements and low losses of the modular multilevel converter with low voltage, highly efficient GaN HEMTs, the presented converter systems achieve high power density and efficiency with minimal filtering requirements. The result of this work is two novel converter systems that will enable further research into lightweight, low volume, power conversion.
DEVELOPMENT OF A SMALL WIND TURBINE ADOPTING FOLDED-PLATE BLADES -PERFORMANCE OF BLADES WITH ONE AND TWO STRAIGHT FOLDING LINES-

The authors have developed a simplified folded-plate blade with high power coefficient for small wind turbine on the design concept of the “Appropriate Technology (AT)”. In this study, the shapes of the blades are the tapered type, the straight type and the inversely tapered type and the diameter of all experimental model is 600[mm], the number of blades is 5, and the thickness of plate is 2[mm]. Each blade has a single folding line. The folding angles for these three types of the blades are 10, 20 and 30[deg] respectively. Blade pitch angles can be changed manually at 0, 5, 10 15, 20 and 25[deg]. In the experiment of all rotors, the wind speed in the wind tunnel is set at 10[m/s] and the torque and the corresponding rotational speed were measured gradually increasing the load. From the results of the experiment, the power coefficient Cp and the tip speed ratio λ were calculated to obtain the power characteristics for different blade types. As a result, the maximum power coefficient for tapered type is Cpmax=0.278 when folded angle is 30[deg] and blade pitch angle is 10[deg]. For the straight type, Cpmax=0.303 when folded angle is 30[deg] and blade pitch angle is 15[deg]. And inversely tapered type is Cpmax=0.337 when folded angle is 30[deg] and blade pitch angle is 15[deg]. The most efficient model was inversely tapered type. Additionally, for the inversely tapered type blades, we examined the performance of them with two straight folding lines whose angles are selected from 5, 10, 15 and 20[deg]. Blade pitch angles are also changed at 0, 5, 10, 15, 20 and 25[deg]. The result shows the maximum power coefficient is 0.372 when two folded lines whose angle are 5[deg], 10[deg] parallel the forward edge with blade pitch angle of 20[deg].
Fan identification and the perception of the sponsor-team fit : The case of Emirates Airlines and Arsenal FC

Sponsorship has become an important factor in determining the success and competitiveness of a sports team. While previous sports sponsorship literature has been substantial, the fans and their perceptions of the sponsor(s) has often not been focused upon. A fans’ identification or connection with a sports team can differ amongst fans, as it influences their engagement with the team and their respective sponsor. Previous literature regarding the perceived fit between a team and a sponsor has been limited to the use of hypothetical sponsors. This research therefore focuses on how different levels of fan identification influence their perceptions of the sponsor-team fit, with a specific focus on the sponsor Emirates Airlines and the football team Arsenal FC.The purpose of this research is to establish an insight into how different levels (high and low) of identified Arsenal FC fans perceive the sponsor-team fit with Emirates Airlines. The research questions have been divided into two sub questions; one focusing on high- identified Arsenal FC fans and the other on low-identified Arsenal FC fans. In order to fulfil the purpose of this thesis, existing literature was used to create an identification survey that was completed by over 100 Arsenal FC fans residing in Sweden. The survey identified a number of high-identified and low-identified fans, of which five high-identified and five low-identified fans were chosen to participate in interviews.The empirical findings reveal that the identification of a sports fan with their sports team does impact their perception of the sponsor-team fit. High-identified fans were more receptive of the sponsor due to their financial support, contributing to a more successful team. Low-identified fans were more receptive of the sponsor due to the duration of the sponsorship, and described this as the main reason to their positive perception of the sponsor-team fit.
Novel adaptive decision threshold modulation technique for UWB direct chaotic communications

A new non-coherent chaotic modulation technique based on adaptive decision threshold is proposed for the UltraWideBand (UWB) Direct Chaotic Communication (DCC) technology. The principal advantages of the proposed technique are: (1) Removing the threshold problem of the classical Chaotic On-Off Keying modulation technique which uses a nonzero decision threshold; (2) Providing a high throughput comparing to the others techniques since it do not uses any delay at the modulation; (3) Reducing the transmitted power, thanks to a transmitted bit energy devised by two. The obtained simulation results show high Bit Error Rate performances of the proposed technique applied in an UWB DCC system. In addition, the new chaotic modulation is more suitable in all DCC-based communications schemes.
The Latin American Household Food Security Measurement Scale (ELCSA) was used to determine food security status in Honduran families with children ages 6 to 60 months

The ELCSA survey was used to determine food security status in Santa Maria and Montaña de la Flor health regions. Households with children ages 6–60 months were randomly selected to participate. The level of food security was determined using the positive responses to the 15 question survey: no positive responses defined food secure, 1–5 defined food insecure, 6–10 defined very food insecure, and 11–15 defined severely food insecure. Within the 140 participating households, 11% of the households were food secure; 14% food insecure, 23% very food insecure, and 53% severely food insecure. Food insecurity was significantly (p ≤ 0.05) associated with having an underweight child (weight‐for‐age z‐score <−2) and telephone ownership; very food insecure with gender of child, living >; one hour from health clinic, electricity, and number of rooms in the house; and severe food insecurity with having an underweight child, child gender, telephone, number of rooms in the house, receiving food assistance, and electricity. Within the rural regions of Honduras evaluated, a very high prevalence of food insecurity exists and is associated with a variety of demographic and socioeconomic factors. These results will assist the Honduran Ministry of Health in directing resources to the heath regions most in need of assistance.
Dissipativity of Linear 0-Methods for Integro-Differential Equations

This paper is concerned with the analytic and numerical dissipativity of nonlinear integro-differential equations (IDEs). A dissipativity criteria for IDEs is given. It is shown that any A-stable linear 0-method for the systems is dissipative. Numerical examples are given to confirm the theoretical results. © 2006 Elsevier Ltd. All rights reserved.
Uncertainty assessment using neural networks and interval neutrosophic sets for multiclass classification problems

This paper presents an approach to multiclass classification. A pair of k-class neural networks are trained to predict k pairs of truth membership and false membership values. The k pairs of errors in the prediction of unknown input patterns are also estimated using interpolation techniques. Two techniques are proposed for the multiclass classification in this paper. First, the truth and false memberships are compared in order to classify the input pattern into multiple classes. Second, estimated errors are used to weight the degrees of truth and false memberships. After that, the results of the combination between weighted truth and weighted false memberships are used for the classification. The estimated errors as well as the difference between the truth and false membership values are considered as the elements of the indeterminacy membership used to identify level of uncertainty in the multiclass classification. Together the three membership values form interval neutrosophic sets. We experiment our technique to the classical benchmark problems including balance, ecoli, glass, lenses, wine, yeast, and zoo from the UCI machine learning repository. Our approach improves classification performance compared to an existing technique which applied only to the truth membership created from a single k-class neural network.
Early Postnatal Administration Of Oleanolic Acid Attenuates The Development Of Non‐Alcoholic Fatty Liver Disease In Fructose Fed Adult Female Rats

The early postnatal period is a critical “window” of developmental plasticity. Dietary manipulations in this phase are associated with the long‐term effects on the development of metabolic syndrome (MetS) and non‐alcoholic fatty liver disease (NAFLD) in adulthood. High fructose diets have been implicated in the rise of the incidence and prevalence of MetS and NAFLD. Current research is exploring the potential use of phytochemicals such as oleanolic acid (OA) to promote neonatal metabolic programming that will impart positive health benefits later in life. Oleanolic acid, a biologically active phytochemical compound, has anti‐diabetic and anti‐obesity effects. We investigated the effects of early postnatal administration of OA on the subsequent development of dietary fructose‐induced metabolic dysfunction and NAFLD in female Sprague Dawley rats.