Evolving small spiking neural networks to work as state machines for temporal pattern recognition

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Techno-Economic Battery Capacity Estimation for Grid-Connected Building-Integrated Photovoltaic Systems

Master's thesis Renewable Energy ENE500 - University of Agder 2017Konfidensiell til / confidential until 01-07-202

Repair and maintenance cost analysis of tractors and combines

The purpose of this study was to collect and analyse current data related to repair and maintenance costs of tractors and combines. Specific objectives of this study were: (a) to collect current repair cost data for tractors and combines; (b) to compare these data with yearly repair cost estimates derived from ASAE repair cost formulas; (c) to estimate expected tractor life; (d) to estimate expected combine life; (e) to study the factors affecting repair costs of tractors and combines; (f) to develop appropriate new repair cost equations for tractors and combines;Two questionnaire surveys were conducted by the author to collect current repair cost data for tractors and combines from a sample of Iowa farmers who owned these machines in 1984 and 1985. Factors affecting repair and maintenance costs of tractors and combines included make and model, age, annual use, and farm size. The results showed that there were no effects of tractor and combine make on repair and maintenance costs. The relationships between repair costs and age were highly significant. Also, the greatest single factor affecting hourly tractor and combine repair costs was the annual use;Testing the validity of the ASAE formulas for predicting repair costs indicated that these formulas, except for one equation, do not accurately predict yearly repair and maintenance costs for Central Iowa tractors and combines. The data show that the average tractor life estimated by the farmers was 8355 hours, and it was 3575 hours for combines. Using the STEPWISE regression procedure to fit the best model for predicting yearly repair costs for tractors and combines leads to the following two equations: For wheel tractor: Y =.072 TAH +.0096 P +.66 H + 78. For self-propelled combine: Y = 241.70 N +.016 P + 2.27 H + 1.07 A - 1894.9. Where: Y = Repair and maintenance costs (/year); TAH = Total accumulated hours of use, at end of year (hrs); P = Purchase price ( ); H = Annual hours of use (hrs); N = Age of the combine (yrs); A = Annual harvested acres (acres)

Evolving spiking neural networks for temporal pattern recognition in the presence of noise

Creative Commons - Attribution-NonCommercial-NoDerivs 3.0 United StatesNervous systems of biological organisms use temporal patterns of spikes to encode sensory input, but the mechanisms that underlie the recognition of such patterns are unclear. In the present work, we explore how networks of spiking neurons can be evolved to recognize temporal input patterns without being able to adjust signal conduction delays. We evolve the networks with GReaNs, an artificial life platform that encodes the topology of the network (and the weights of connections) in a fashion inspired by the encoding of gene regulatory networks in biological genomes. The number of computational nodes or connections is not limited in GReaNs, but here we limit the size of the networks to analyze the functioning of the networks and the effect of network size on the evolvability of robustness to noise. Our results show that even very small networks of spiking neurons can perform temporal pattern recognition in the presence of input noiseFinal Published versio

Level of Happiness among Kuwait University Students after the Covid-19 Pandemic in Light of some Variables

هدفت الدراسة الحالية إلى الكشف عن مستوى الشعور بالسعادة لدى طلبة جامعة الكويت بعد جائحة كوفيد-19 في ضوء بعض المتغيرات، وتم استخدام المنهج الوصفي المقارن، وتضمنت عينة الدراسة الأساسية (237) طالباً وطالبة من طلبة جامعة الكويت. وتم استخدام استبيان أكسفورد للسعادة من إعداد هيلز وأرجيل (2002). وبينت نتائج الدراسة وجود مستوى منخفض من الشعور بالسعادة لدى طلبة جامعة الكويت، وقد بين حوالي (32%) من الطلبة أنهم غالبًا ما يشعرون بالسعادة، وبين حوالي (23.5%) من الطلبة أنهم نادرًا ما يشعرون بالسعادة، بينما بين حوالي (44.5%) من الطلبة أنهم أحيانًا ما يشعرون بالسعادة، ولا توجد فروق بين الطلاب والطالبات في الشعور بالسعادة، وهناك أربع متغيرات تؤثر في الشعور بالسعادة لدى طلبة جامعة الكويت، وهي: المستوى الاقتصادي، والحالة النفسية، والحالة الصحية، والسمنة.The current study aimed to explore the level of happiness among Kuwait university students in light of some variables. The comparative descriptive method was used. The sample consisted of (237) male and female students from Kuwait University. The Oxford Happiness Questionnaire prepared by Hills and Argyle (2002) was used. The results of the study showed that the level of happiness among Kuwait University students is low. About (32%) of the students indicated that they often feel happy, and about (23.5%) of the students rarely feel happy, while about (44.5%) of the students sometimes feel happy. There aren’t differences between male and female students in the feeling of happiness. There are four variables that affect the feeling of happiness among Kuwait University students: the economic level, psychological status, health status, and obesity

Evolution of Spiking Neural Networks for Temporal Pattern Recognition and Animat Control

I extended an artificial life platform called GReaNs (the name stands for Gene Regulatory evolving artificial Networks) to explore the evolutionary abilities of biologically inspired Spiking Neural Network (SNN) model. The encoding of SNNs in GReaNs was inspired by the encoding of gene regulatory networks. As proof-of-principle, I used GReaNs to evolve SNNs to obtain a network with an output neuron which generates a predefined spike train in response to a specific input. Temporal pattern recognition was one of the main tasks during my studies. It is widely believed that nervous systems of biological organisms use temporal patterns of inputs to encode information. The learning technique used for temporal pattern recognition is not clear yet. I studied the ability to evolve spiking networks with different numbers of interneurons in the absence and the presence of noise to recognize predefined temporal patterns of inputs. Results showed, that in the presence of noise, it was possible to evolve successful networks. However, the networks with only one interneuron were not robust to noise. The foraging behaviour of many small animals depends mainly on their olfactory system. I explored whether it was possible to evolve SNNs able to control an agent to find food particles on 2-dimensional maps. Using ring rate encoding to encode the sensory information in the olfactory input neurons, I managed to obtain SNNs able to control an agent that could detect the position of the food particles and move toward it. Furthermore, I did unsuccessful attempts to use GReaNs to evolve an SNN able to control an agent able to collect sound sources from one type out of several sound types. Each sound type is represented as a pattern of different frequencies. In order to use the computational power of neuromorphic hardware, I integrated GReaNs with the SpiNNaker hardware system. Only the simulation part was carried out using SpiNNaker, but the rest steps of the genetic algorithm were done with GReaNs

Pyloromyotomy for infantile hypertrophic pyloric stenosis using a modification of the Tan and Bianchi circumumbilical approach

Background/purpose Different approaches have been advocated for pyloromyotomy.  Since the introduction of umbilical pyloromyotomy, a number of studies have shown that it is as safe as the traditional right upper quadrant approach with superior  cosmetic results. The aim of this study was to assess the feasibility and the safety  of pyloromyotomy for infantile hyprtrophic pyloric stenosis using a modification of the Tan–Bianchi approach.Patients and methods Over a period of 2 years, 20 infants with infantile  hypertrophic pyloric stenosis have been clinically evaluated. The umbilical approach was modified so that a transverse muscle cutting incision rather than a longitudinal midline linea alba incision was performed.Results The total number of cases included in this study was 20 [16 male (80%)  and four female (20%) patients]. Their ages ranged from 23 to 60 days (average  42.6 ±13.54 days), and their weights ranged from 2700 to 4000 g (mean 3605± 437.4 g). Pyloromyotomy was performed safely with negligible blood loss. Four cases of serosal tear occurred, with an incidence of 20%. None of our cases showed significant complications. The mean operating time was 52.5 ± 5.073 min. The postoperative hospital stay ranged from 24 to 72 h. The postoperative course was uneventful in all patients, and, on follow-up, the circumumbilical incision left an almost undetectable scar.Conclusion Pyloromyotomy for infantile hypertrophic pyloric stenosis using the modified Tan and Bianchi technique is feasible and safe, having an accepted operative time, early initiation of postoperative feeding, and short hospital stay. This modification combines the advantage of circumumbilical incision with its better cosmetic results and right transverse upper abdominal approach with its easy and feasible access to the pyloric mass.Keywords: operative intervention, pyloric stenosis, Tan–Bianchi approac

Characterization of flame propagation and burning rates of various mixtures of biogas and nitrous oxide

Biogas is a potential alternative energy source with low environmental impact. However, the practical applications of biogas are relatively limited due to the existence of carbon dioxide (CO2) which acts as a diluent that decreases the calorific value and the burning rate of biogas. Nitrous oxide (N2O) is known to be a powerful oxidizing agent for propulsion applications which can enhance the combustion rate of biogas, however, there is a lack of studies that investigate the fundamental characteristics of biogas-N2O combustion. The aim of this study is to gain insight into the fundamental combustion characteristics of biogas-N2O mixtures in terms of laminar burning velocity and flame stability. In the present work, spherically expanding flames following central ignition at constant volume combustion chamber (CVCC) were employed to investigate laminar burning velocity (LBV), hydrodynamic instability, and diffusive-thermal instability of biogas-N2O mixtures at wide equivalence ratio;?, from 0.6 to 1.4, at 303K and atmospheric pressure. Two mechanisms were used in CHEMKIN-PRO 17 software in order to estimate the predicted combustion characteristics of biogas-N2O mixtures. The results indicate that the decline in LBVs was prominent in the fuel-rich mixtures than in the fuel-lean mixtures with CO2 dilution. It is found that the influence of curvature on the flame front is weakened at the fuel lean-to-stoichiometric mixture due to the decrease in the flame thickness. Therefore, flame instability tends to increase at the lean-to-stoichiometric region. The increase in CO2 in biogas by 10%, increases the Lewis number (Le) value by 3.6% to 4.6%. The diffusive-thermal instability was dominant for all biogas-N2O mixtures, as Le was less than unity throughout the entire equivalence ratio range. The thermal reaction of N2O decomposition is the most significant reaction in biogas-N2O combustion at lean mixtures of ? = 0.6 and ? = 0.8. The LBVs of biogas-N2O mixture revealed a considerable enhancement at the lean equivalence ratio of 0.8 compared to the other biogas-air mixtures with H2 addition. The effect of nitrous oxide as an oxidizer on biogas detonation characteristics is studied numerically using Chemical Equilibrium Applications (CEA) and compared with other oxidizers. Mixtures with N2O oxidant revealed 32% and 16% higher detonation pressure and detonation Mach number, respectively, at ? = 0.6, compared to that of mixtures with pure oxygen oxidant. Overall, employing N2O oxidant has enhanced the fundamental combustion characteristics of biogas significantly, which may lead to the use of biogas as a clean fuel in commercial applications that demand high combustion rates, such as power generation and aerospace

PHIPS-HALO: The airborne Particle Habit Imaging and Polar Scattering probe-Part 1: Design and operation

This is an Open Access article distributed under the terms ofthe Creative Commons Attribution 3.0 License https://creativecommons.org/licenses/by/3.0/The number and shape of ice crystals present in mixed-phase and ice clouds influence the radiation properties, precipitation occurrence and lifetime of these clouds. Since clouds play a major role in the climate system, influencing the energy budget by scattering sunlight and absorbing heat radiation from the earth, it is necessary to investigate the optical and microphysical properties of cloud particles particularly in situ. The relationship between the microphysics and the single scattering properties of cloud particles is usually obtained by modelling the optical scattering properties from in situ measurements of ice crystal size distributions. The measured size distribution and the assumed particle shape might be erroneous in case of non-spherical ice particles. There is a demand to obtain both information correspondently and simultaneously for individual cloud particles in their natural environment. For evaluating the average scattering phase function as a function of ice particle habit and crystal complexity, in situ measurements are required. To this end we have developed a novel airborne optical sensor (PHIPS-HALO) to measure the optical properties and the corresponding microphysical parameters of individual cloud particles simultaneously. PHIPS-HALO has been tested in the AIDA cloud simulation chamber and deployed in mountain stations as well as research aircraft (HALO and Polar 6). It is a successive version of the laboratory prototype instrument PHIPS-AIDA. In this paper we present the detailed design of PHIPS-HALO, including the detection mechanism, optical design, mechanical construction and aerodynamic characterization.Final Published versio

Immunopathological comparison of in ovo and post-hatch vaccination techniques for infectious bursal disease vaccine in layer chicks

This study was designed to compare immunopathological effects of in ovo vaccination with post-hatch vaccination against IBD in White Leghorn chicks. A total of 189 embryonated eggs were divided into six groups. At day 18 of incubation, groups A–C were administered in ovo with 228E, Winterfield 2512:10/3 and 2512/90:10/2.7, respectively, group D (post-hatch vaccination) and group E as shamed control (for quality evaluation of in ovo vaccination technique), and group F as control. The results showed that antibody titers against IBD detected by ELISA on days 2, 17, and 28 were significantly higher in all in ovo groups as compared to control groups E and F. On day 17, all vaccinated groups (in ovo and post-hatch vaccinated) showed no significant differences in antibody titers among themselves; however, at day 28, only the post-hatch group showed significantly higher antibody titers followed by in ovo vaccinated groups. The cell-mediated immunity determined by PHA-P assay was significantly higher in all vaccinated groups than the non-vaccinated groups. No clinical signs of IBD infection were observed in any of the vaccinated groups. There was only increase in bursa size of groups vaccinated with intermediate plus strains (groups A, C, and D) at day 28. The histopathology showed that all the treatment groups had mild lesions induced by IBD virus in bursa. This study concluded that in ovo vaccination with live IBD vaccines provides protective immunity to the chickens even in the presence of IBD-specific MDA; therefore, the onset of immunity was much earlier than the post-hatch vaccination and in ovo groups also maintained protective immunity against IBD for longer time