Combustion analysis of a CI engine performance using waste cooking biodiesel fuel with an artificial neural network aid

[Abstract]: A comprehensive combustion analysis has been conducted to evaluate the performance of a commercial DI engine, water cooled two cylinders, in-line, naturally aspirated, RD270 Ruggerini diesel engine using waste vegetable cooking oil as an alternative fuel. In order to compare the brake power and the torques values of the engine, it has been tested under same operating conditions with diesel fuel and waste cooking biodiesel fuel blends. The results were found to be very comparable. The properties of biodiesel produced from waste vegetable oil was measured based on ASTM standards. The total sulfur content of the produced biodiesel fuel was 18 ppm which is 28 times lesser than the existing diesel fuel sulfur content used in the diesel vehicles operating in Tehran city (500 ppm). The maximum power and torque produced using diesel fuel was 18.2 kW and 64.2 Nm at 3200 and 2400 rpm respectively. By adding 20% of waste vegetable oil methyl ester, it was noticed that the maximum power and torque increased by 2.7 and 2.9% respectively, also the concentration of the CO and HC emissions have significantly decreased when biodiesel was used. An artificial neural network (ANN) was developed based on the collected data of this work. Multi layer perceptron network (MLP) was used for nonlinear mapping between the input and the output parameters. Different activation functions and several rules were used to assess the percentage error between the desired and the predicted values. The results showed that the training algorithm of Back Propagation was sufficient enough in predicting the engine torque, specific fuel consumption and exhaust gas components for different engine speeds and different fuel blends ratios. It was found that the R2 (R: the coefficient of determination) values are 0.99994, 1, 1 and 0.99998 for the engine torque, specific fuel consumption,CO and HC emissions, respectively

Investigation of the effects of buffer gas pressure, electrical input power and pulse repetition rate on the output power of a metal vapor laser

The effects of buffer gas pressure, electrical input power and pulse repetition frequency on the output power of 510.6nm and 578.2nm transitions have been experimentally investigated in a copper vapor laser with small-bore tube (11mm of diameter and 580mm of length). It is observed that the output power characteristics are strongly influenced by these parameters. A maximum output power of laser is obtained at about 4W with 27 kHz of pulse repetition frequency, 30 torr of Ne buffer gas pressure and 1.42kW of electrical input power. The waveforms of the current, tube voltage and laser pulses have also been observed

Efectos de los períodos de reposo muy cortos en la relación de testosterona y cortisol durante ejercicios de alta resistencia en hombres

La relación entre la concentración de testosterona y cortisol (relación T/C) se suele utilizar como índice del nivel de esfuerzo en la práctica de ejercicio físico. Los cambios que se producen en esta relación son los responsables de varias reacciones al ejercicio, como la hipertrofia y el aumento de fuerza. Así, el objetivo de este estudio fue explorar el efecto de 4 series de press banca y sentadillas hasta el fallo con 85% de 1 RM utilizando diferentes intervalos de reposo de 60 (P60), 90 (P90) y 120 (P120) segundos sobre la relación de testosterona y cortisol en hombres entrenados en ejercicios de resistencia. Diez hombres entrenados en ejercicios de resistencia por placer (edad: 22±2 años; peso: 84±8kg; altura: 178,5±8,5; con 1 año de experiencia como mínimo en ejercicios de resistencia [ER]) realizaron protocolos de ER en sesiones aleatorias por separado. Se extrajeron muestras de sangre antes del ejercicio (pre), inmediatamente después (post) y 30min después del fin de la sesión (30-post) para analizar las concentraciones séricas de testosterona y cortisol. Los resultados de este estudio indicaron que la relación T/C en el intervalo P60 fue significativamente más baja en post y 30-post en comparación con la previa al ejercicio (p≤0,05). La relación T/C después del ejercicio fue significativamente más alta en P120 que en P60 y P90 (p≤0,05), pero no se observaron diferencias entre P60 y P90. Los datos indican que el período de reposo largo entre series en ER hasta el fallo obtuvo un aumento mayor de la relación T/C que el período de reposo corto. La mejora de la relación T/C mediante períodos de reposo largos entre series indica un aumento del estado anabólico hasta el ER en hombres entrenados en ejercicios de resistencia

Efecte de la relació dels períodes de repòs molt breus en la testosterona i el cortisol durant l’exercici d’alta resistència en homes

La relació entre la concentració de testosterona i cortisol (relació T/C) se sol utilitzar com a índex del nivell d’esforç en l’entrenament esportiu. Els canvis que es produeixen en aquesta relació són responsables de moltes reaccions a l’exercici, com la hipertrofia i l’augment de força. L’objectiu d’aquesta recerca fou estudiar l’efecte de 4 sèries d’exercicis de pressió sobre banc i esquat fins a l’esgotament amb el 85% d’1 RM, sobre la relació de testosterona i cortisol d’homes entrenats en exercicis de resistència, utilitzant diferents intervals de repòs de 60 (P60), 90 (P90) i 120 (P120) segons. Deu homes entrenats en exercicis de resistència no competitiva (edat: 22 ± 2 anys; pes: 84 ± 8 kg; alçada: 178,5 ± 8,5 cm, amb un un any d’experiència com a mínim en exercicis de resistència [ER]), realitzaren protocols d’ER en sessions aleatòries, per separat. Es van extreure mostres de sang abans de l’exercici (Pre), immediatament després (Post) i 30 min després de finalitzar la sessió (30Post) per analitzar les concentracions sèriques de testosterona i de cortisol. Els resultats d’aquest estudi mostraren que la relació T/C durant l’interval P60 fou significativament més baixa en Post i 30Post en comparació amb el preexercici-exercici (p ≤ 0,05). La relació T/C després de l’exercici fou significativament més alta en P120 que en P60 i P90 (p ≤ 0,05), però no s’observaren diferències entre P60 i P90. Les dades indiquen que el període de repòs llarg entre sèries en ER fins a l’esgotament obtingué un augment major de la relació T/C que en el període de repòs breu. La millora de la relació T/C mitjançant períodes de repòs llarg entre sèries indica un augment de l’estat anabòlic fins a l’ER en homes entrenats en exercicis de resistència.La relació entre la concentració de testosterona i cortisol (relació T/C) se sol utilitzar com a índex del nivell d’esforç en l’entrenament esportiu. Els canvis que es produeixen en aquesta relació són responsables de moltes reaccions a l’exercici, com la hipertrofia i l’augment de força. L’objectiu d’aquesta recerca fou estudiar l’efecte de 4 sèries d’exercicis de pressió sobre banc i esquat fins a l’esgotament amb el 85% d’1 RM, sobre la relació de testosterona i cortisol d’homes entrenats en exercicis de resistència, utilitzant diferents intervals de repòs de 60 (P60), 90 (P90) i 120 (P120) segons. Deu homes entrenats en exercicis de resistència no competitiva (edat: 22 ± 2 anys; pes: 84 ± 8 kg; alçada: 178,5 ± 8,5 cm, amb un un any d’experiència com a mínim en exercicis de resistència [ER]), realitzaren protocols d’ER en sessions aleatòries, per separat. Es van extreure mostres de sang abans de l’exercici (Pre), immediatament després (Post) i 30 min després de finalitzar la sessió (30Post) per analitzar les concentracions sèriques de testosterona i de cortisol. Els resultats d’aquest estudi mostraren que la relació T/C durant l’interval P60 fou significativament més baixa en Post i 30Post en comparació amb el preexercici-exercici (p ≤ 0,05). La relació T/C després de l’exercici fou significativament més alta en P120 que en P60 i P90 (p ≤ 0,05), però no s’observaren diferències entre P60 i P90. Les dades indiquen que el període de repòs llarg entre sèries en ER fins a l’esgotament obtingué un augment major de la relació T/C que en el període de repòs breu. La millora de la relació T/C mitjançant períodes de repòs llarg entre sèries indica un augment de l’estat anabòlic fins a l’ER en homes entrenats en exercicis de resistència

Effects of very short rest periods on testosterone to cortisol ratio during heavy resistance exercise in men

The ratio between testosterone and cortisol concentration (Ts/Co ratio) is frequently used as an index of the stress level in exercise training. Changes in this ratio are responsible for several training responses such as hypertrophy and strength gain. So the purpose of this study was to investigate the effect of 4 sets of bench press and squat to failure with %85 of 1RM using different rest intervals of 60 (P60), 90 (P90) and 120 (P120) second on testosterone to cortisol ratio in resistance trained men. Ten recreationally resistance-trained men (age, 22±2 years; weight, 84±8kg; height, 178.5±8.5; at least 1 year of resistance exercise [RE] experience) performed RE protocols on randomized separating session. Blood draws occurred at pre-exercise (Pre); immediately after (Post) and 30min after the end of the session (30Post) for measurement serum testosterone and cortisol concentrations. The results of this study indicated that Ts/Co ratio in P60 trail was significantly lower at post and 30min post compare to pre-exercise (p≤0.05). The Ts/Co ratio at post exercise was significantly higher in P120 than P60 and P90 (p≤0.05), but no difference was found between P60 and P90. The data indicate that long rest period between sets in RE to failure resulted in a grater increase in Ts/Co ratio than short rest period between sets in RE. The enhanced in Ts/Co ratio by long rest period between sets, indicating an augmented anabolic state to RE in resistance trained men

Investigation of radial flow ejector performance through experiments and computational simulations

Adjustability in ejector geometry is desirable to extend the operating range of ejectors at different working conditions. Current approaches to geometric adjustability in the throat sizes of conventional axial ejectors have the disadvantage of blocking the flow path by positioning additional components in the high-speed flow. Furthermore, a viable mechanical system is not available for altering the diameters of the nozzle and ejector throat while providing gas-tight seals and a smooth surface throughout. An alternative concept, the radial ejector, has been created which makes possible a practical ejector that can readily achieve variable geometry without introducing additional flow blockage in the center of the high-speed flow. Such a radial configuration allows geometry adjustment during operation to achieve optimum performance at a range of different operating conditions without additional pressure losses from high-speed flow blockage. The radial ejector conceived, designed, commissioned and evaluated in this thesis was formed from two disk-like surfaces for both the primary nozzle and the ejector body enabling the radial ejector to operate with different flow areas by simply changing the separation of the ejector duct walls or the nozzle plates. Conventional axial flow ejector design procedures were adapted in the design process, and benchmarking against an experimental axial ejector was also performed. Air was employed as the working fluid to improve fabrication options and allow experiments to be performed with an open system. The radial ejector has a nozzle throat area of 8.8 mm2, nozzle exit area of 180 mm2, giving a nozzle area ratio of 20.4, and an ejector physical throat area of 520 mm2, giving the ejector area ratio of 59. Experimental results show that the radial ejector produced entrainment ratios between 0.95 and 0.24 and critical pressure lift ratios around 1.5 for expansion ratios between 50 and 139. The relationships between the entrainment ratio and critical exit pressure and primary, secondary and exit pressures were similar to conventional axial ejectors. Similarly, trends observed in the measurements of wall pressure for the radial ejector configuration were generally consistent with those for axial flow ejectors. Based on the experimental data from the critical mode ejector operation and based on an isentropic flow calculation, a secondary stream Mach number of around 0.7 was determined at the physical throat of the ejector. When ejector operation transitioned from the critical to the subcritical mode, wall pressures in the throat and at locations upstream of the throat increased, leading to a peak in pressure prior to the final pressure rise in the diffuser. Comparing the experimental results with the simulations show that the entrainment ratio achieved from the radial ejector prototype agreed well. The entrainment ratio performance also closely matched that of a quasi-one-dimensional gas dynamic model with an error level less than 10%. Computational Fluid Dynamic (CFD) analysis based on the k-epsilon standard turbulence model showed that simulations of entrainment ratio and critical back pressure were in reasonable agreement with the experimental results with an average discrepancy of less than 16%. Using the k-omega SST turbulence model, it was demonstrated that adjustability in the radial ejector is viable and by increasing the separation of the ejector duct walls from 2.2 mm to 3 mm, an increase of 34% in entrainment ratio can be achieved. A critical back pressure increase of 40% was achieved by reducing the separation of the ejector duct walls from 3 mm to 2.2 mm. However, as there are systematic differences between the measurements and the computational simulations using both the k-omega SST or the k-epsilon standard model, the overall reliability of the CFD simulations is questionable. The main issue for the current prototype radial ejector is the low critical exit pressure relative to expected performance from an equivalent axial flow ejector. More experiments and simulation are required to improve this aspect of the radial ejector performance. The radial ejector geometry is required to be optimized and many different flow features need extensive investigation to identify ways to achieve better performance and expand the adjustability options in the radial ejector

Oil Produktion Affected by ASP and Gelation Technologies

Проведено аналіз впливу технологій внесення інгібітору корозії ASP і технологій огелювання на рівень нафтовидобутку. Показано, що технології огелювання були розроблені для забезпечення більш ефективного вертикального розгорнення, для затоплення природно тріщинуватих порід-колекторів нафти. Наведено результати аналізу ефективності використання комбінації цих двох технологій, які, на думку автора, могли б розширити застосовність лужного поверхнево-полімерного заводнення.Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency for those with high permeability contrast «thief zones». The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than water flooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or those with thief zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. Aluminum citrate-polyacrylamide, resorcinol-formaldehyde, and the silicate-polyacrylamide gel systems did not produce significant incremental oil in linear core floods. Both flowing and rigid flowing chromium acetatepolyacrylamide gels and the xanthan gum-chromium acetate gel system produced incremental oil with the rigid flowing gel producing the greatest amount. Higher oil recovery could have been due to higher differential pressures across cores. None of the gels tested appeared to alter alkaline-surfactant-polymer solution oil recovery. Total water flood plus chemical flood oil recovery sequence recoveries were all similar

Optimum formulation of asp for injection in oil reservoir

Проведено аналіз оптимального складу інгібіторів корозії ASP для нагнітання у нафтовий пласт. Звертається увага на проблему додавання води в нафтовий резервуар, що є, на думку автора, єдиним методом відновлення тиску в резервуарі.Enhanced Oil Recovery is not a new process and it has been utilized by the Oil and Gas industry for several decades, particularly in the use of water flooding as a secondary recovery measure to ensure maintenance of reservoir pressure.1Adding water to an oil reservoir may seem an odd thing to do- anything added to the reservoir should aid in maintaining reservoir pressure, so why add water, as oil and water do not mix? The problem is that most oil reservoirs are solution gas driven, this means that as the oil is produced the reservoir pressure is reduced and the gas that was held in solution is released and expands. This process drives the oil to the producing wells, however the gas is also free to flow and be produced. Once the gas is produced, the reservoir's energy is lost and reservoir pressure is reduced. If this process is the only method of recovery, it will only yield up to 20% of the reservoirs total volume

Dissection of the genetic basis of genotype-by-environment interactions for grain yield and main agronomic traits in Iranian bread wheat landraces and cultivars

Understanding the genetic basis of performance stability is essential to maintain productivity, especially under severe conditions. In the present study, 268 Iranian bread wheat landraces and cultivars were evaluated in four well-watered and two rain-fed conditions for different traits. According to breeding programs, cultivars were in a group with a high mean and stability in terms of GY, GN, and SW traits, while in terms of PH, they had a low mean and high stability. The stability of cultivars and landraces was related to dynamic and static stability, respectively. The highest number of marker pairs and lowest LD decay distance in both cultivars and landraces was observed on the B genome. Population structure differentiated indigenous cultivars and landraces, and the GWAS results for each were almost different despite the commonalities. Chromosomes 1B, 3B, 7B, 2A, and 4A had markers with pleiotropic effects on the stability of different traits. Due to two rain-fed environments, the Gene Ontology (GO) confirmed the accuracy of the results. The identified markers in this study can be helpful in breeding high-performance and stable genotypes and future breeding programs such as fine mapping and cloning

Continuous Reinforcement Learning-based Dynamic Difficulty Adjustment in a Visual Working Memory Game

Dynamic Difficulty Adjustment (DDA) is a viable approach to enhance a player's experience in video games. Recently, Reinforcement Learning (RL) methods have been employed for DDA in non-competitive games; nevertheless, they rely solely on discrete state-action space with a small search space. In this paper, we propose a continuous RL-based DDA methodology for a visual working memory (VWM) game to handle the complex search space for the difficulty of memorization. The proposed RL-based DDA tailors game difficulty based on the player's score and game difficulty in the last trial. We defined a continuous metric for the difficulty of memorization. Then, we consider the task difficulty and the vector of difficulty-score as the RL's action and state, respectively. We evaluated the proposed method through a within-subject experiment involving 52 subjects. The proposed approach was compared with two rule-based difficulty adjustment methods in terms of player's score and game experience measured by a questionnaire. The proposed RL-based approach resulted in a significantly better game experience in terms of competence, tension, and negative and positive affect. Players also achieved higher scores and win rates. Furthermore, the proposed RL-based DDA led to a significantly less decline in the score in a 20-trial session