COMPARISONS OF ACUTE NEUROMUSCULAR FATIGUE IN MAXIMAL EFFORT STRENGTH TRAINING USING POWERLIFTS. N. T. Theilen, B. I. Campbell, M. C. Zourdos2, J. M. Oliver3, J. O'Halloran1, N. Asher1, J. M. Wilson4 1University of South Florida, Exercise and Performance Nutrition Laboratory, Tampa, FL 2Florida Atlantic University, Boca Raton, FL 3Texas Christian University, Fort Worth, TX 4University of Tampa, Tampa, FL Neuromuscular fatigue is associated with a decrease in velocity. Following powerlift training, the extent to which fatigue affects the performance velocity of each lift after a specified recovery interval has not yet been investigated. Purpose To assess the level of acute neuromuscular fatigue, as measured by a decrease in peak velocity, as a result of maximal effort strength training sessions with each powerlift. Methods Twelve resistance trained males (22.8 ± 2.6 yrs; 177.1 ± 6.7 cm; 83.0 ± 12.6 kgs) participated in a randomized crossover design with three conditions: Squat (SQ), Bench Press (BP), and Deadlift (DL). Subjects' relative strength included the ability to successfully complete at least 1.5x their bodyweight in the squat exercise. Initially, baseline peak velocity (PV) was measured for each lift at 60% 1RM via a TENDO unit. One training session occurred each Monday for 3 consecutive weeks (1 week for each lift). Each training session consisted of a 1RM of the designated lift followed by 4 sets of 2 repetitions at 92.5% and 4 sets of 3 repetitions at 87.5%. Following training sessions, each lift PV was measured at 24, 48, and 72 hours post-training to compare with baseline measures and determine recovery. Data was analyzed using a repeated measures ANOVA (p<.05). Results SQ: No significant differences in PV of the SQ and DL following SQ training at each time point compared to baseline. Bench press PV significantly declined following squat training (Baseline = 1.069 m/s; 24 hours = 0.974 m/s [p = 0.019]; 48 hours = 1.015 m/s [p = 0.034]; 72 hours = 0.970 m/s [p = 0.004]. BP: No significant differences in PV of the SQ and DL following BP training at each time point compared to baseline. Bench press PV significantly declined only at 24 hours following BP training (Baseline = 1.069 m/s; 24 hours = 0.988 m/s [p = 0.004]). DL: No significant differences in PV of the DL following DL training as compared to baseline. Squat PV significantly declined at 24 hours following the DL training (Baseline = 1.384 m/s; 24 hours = 1.315 m/s [p = 0.032]. Similar to SQ, PV of the BP significantly declined only at 24 hours following DL training (Baseline = 1.069 m/s; 24 hours = 0.979 m/s [p < 0.001]). Conclusions Bench press PV was significantly decreased 24-hours following each of the three powerlifts as compared to baseline values. Interestingly, there were no changes in squat and deadlift PV following training of that specific lift. Practical Applications Regardless of the powerlift trained, bench press PV at 60% was compromised 24-hours later. Therefore, following training of any powerlift, more than 24-hours may be needed to optimize performance in the BP at submaximal intensities.

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The first step in many mining operations is blasting, and the purpose of blasting is to fragment the rock mass in the most efficient way for that mine site and the material end use. Over time, new developments to any industry occur, and design and implementation of traditional techniques have to change as a consequence. Possibly the greatest improvement in blasting in recent years is that of electronic detonators. The improvements related to safety and increased fragmentation have been invaluable. There has been ongoing debate within the explosives industry regarding two possible theories for this. Shorter timing delays that allow interaction between adjacent shock waves or detonation waves, or the increase in accuracy associated with electronic detonators. Results exist on the improved accuracy of electronic detonators over that of electric or non-electric, but data on the relationship between the collision of dynamic stress waves and fragmentation is less understood. Publications stating that the area of greatest fragmentation will occur between points of detonation where shock waves collide exist, but experimental data to prove this fact is lacking. This dissertation looks extensively at the head on collision of shock (in the rock mass) and detonation (in the detonation column) waves with relation to fragmentation through a number of small scale tests in concrete. Timing is a vital tool for this collision to occur and is the variable utilized for the studies. Small scale tests in solid masonry blocks, 15 x 7⅞ x 7⅞ inches in size, investigated shock and detonation wave collisions with instantaneous detonation. Blocks were wrapped in geotextile fabric and a wire mesh to contain the fragments so that in situ tensile crack formations could be analyzed. Detonating cord was used as the explosive with no stemming to maintain the shock pressure but reduce the gas pressure phase of the fragmentation cycle. Model simulations of these blocks in ANSYS Autodyn looked at the stress and pressure wave patterns and corresponding damage contours for a direct comparison with the experimental investigation. Detonation wave collision in a single blast hole was found to positively influence the fragmentation and throw of the material. Mean fragment size decreased compared to tests with no detonation wave collision. Area of greatest throw occurred at the point of detonation collision where a buildup of gas pressure exited the block from one location. Head on collision of shock waves did not positively influence the muck pile. Largest fragments were located at the point of shock collision. The lack of particle velocity with relation to shock collision in previous literature could be attributed to the increased particle size here. Directional particle velocities could actually increase the strength and density of the rock at this location, decreasing the degree of fragmentation rather than increasing it.

In this thesis a model is developed for calculating the loads on the wetclutches in apowershift transmission. This thesis was done at Volvo CE in Eskilstuna and is focusedon their 4-speed countershaft transmissions. The goal of the project is to be able tocalculate the loads automatically during the transmission tests and thus acquire increasedknowledge about what occurs during operation.The model was developed by first generating a number of concepts and then evalu-ating them to decide which one should be developed further. The chosen concept wasthen developed further and implemented into the test equipment as a calculation script.The chosen loads to model were the energy absorbed in each clutch, the coefficient offriction (COF) and the slip distance. The COF was later found to give too unreliableresults to be used in any other way than as a benchmark for how well the model wasconfigured and to see any large changes in COF.The model was validated by calculating the energy absorbed in a HTE-200 seriestransmission and comparing it to a reference calculation model. It was seen that theresults from the new model are very close to the reference result. The energy lostcalculated by the new model will be equal to 94 % of the energy lost calculated by thereference model, but only when measuring the inertia phase. The energy lost is equalto 135 % when the torque phase is included. The increasing difference is believed tobe because of an error in the reference model that means it does not cover the torquephase.

Based on the analysis of the empirical research data from a Survey Questionnaire completed by 374 lawyers and 197 clients who participated in 606 judicially conducted Judicial Dispute Resolution (JDR) sessions (JDR Program) in the Court of Queens Bench of Alberta (the Court) in the year ending June 2008, the authors judicial experience, and legal literature research, it is asserted that the Courts JDR Program has become an integral, normative, and institutional part of the resolution of disputes litigated in the Court. This has been achieved through a judicially led process utilizing multi-faceted dispute resolution techniques, with considerable quantitative and qualitative success. All this has led to more demand by lawyers and litigants for the JDR Program, in which these components have, over time, combined in a symbiotic and synergistic way. Thus, it is asserted that the Multi-door Courthouse is open in Alberta. / Dispute Resolution

La propulsion hybride utilise classiquement un comburant liquide (ou gazeux) injecté dans une chambre de combustion qui contient le carburant à l'état solide. La flamme de diffusion, qui apparait à la rencontre des deux flux de matière, est autoentretenue par la pyrolyse du carburant consécutive à l’apport de chaleur produite par la combustion. Afin d'améliorer les performances de ce type de propulsion, il est nécessaire de bien comprendre le couplage physicochimique des phénomènes. Le couple d'ergols polyéthylène/mélange gazeux dioxygène et diazote a été choisi pour cette étude. Les caractéristiques du polyéthylène ont été déterminées par des analyses physicochimiques, elles permettent de mettre en évidence un effet de la pression et de la nature de l'atmosphère sur la composition des produits de pyrolyse. Un banc d'essais de combustion avec une instrumentation a permis de caractériser le comportement du polyéthylène en situation réelle. Les données acquises ont été analysées afin d'obtenir des grandeurs physiques pertinentes à comparer avec des résultats de simulations. Pour effectuer des simulations de chambre de combustion de propulseur hybride, le développement d'un modèle numérique instationnaire et bidimensionnel a débuté. De nombreux cas test "académiques" sont présentés et ont confirmés la bonne implémentation des méthodes numériques de résolution et des équations physiques et chimiques. Cependant, lors des simulations de la chambre de combustion complète, une divergence de pression est apparue dont les causes ont été activement recherchées. / The hybrid space propulsion classically employs a liquid (or gaseous) oxidizer injected into the combustion chamber which contains the solid reducer. The diffusion flame, which appears at the confluence of the oxidizer and reducer mater fluxes, is auto-entertained by the fuel pyrolysis piloted by the heat which is provided to it by the combustion. In order to increase performances of this propulsion system, it is necessary to well understand the coupling effect of the physical and chemical phenomena. The propellants couple polyethylene/gaseous oxygen and nitrogen mixture has been chosen for this study. Properties of the polyethylene have been determined by several chemical analyses, showing that there are a pressure and atmosphere nature effects on the pyrolysis chemical composition. A test bench with instrumentation allowed to characterize the behavior of the polyethylene in real situation. Data acquired have been analyzed in order to obtain physical variables relevant for comparing the numerical simulations results. To undertake simulation of the combustion chamber of hybrid rocket, a new numerical model has been developed. Numerous "academic" test cases are presented and confirmed a good implementation of the numerical method and of the physical and chemical models. Nevertheless, during simulations of hybrid combustion chamber, a pressure divergence has appeared thus causes have been actively investigated.

Actuators are a fundamental part of many modern devices and machines nowadays. Typically, they are responsible for operation of various machine parts, for instance correct performance of flaps and valves. Since actuators are an important device, it is crucial and beneficial to pursue development and testing of this component. This Master's thesis focusses on the selection and construction of a test bench used for long-term tests of a universal actuator (General Purpose Actuator), widely used in automobile industry. The main reason for assigning this practical task is the unsatisfactory current type of the test bench, which does not comply with the modern testing demands of the requesting company.

O presente trabalho apresenta o desenvolvimento de uma bancada didática de baixo custo para estudo dos materiais termoelétricos para a realização de ensaios de obtenção de curvas de desempenho dos módulos termoelétricos no que se refere a geração de energia pelo Efeito Seebeck e resfriamento através do Efeito Peltier de forma a difundir os conhecimentos nas áreas afim em escolas de Engenharia, refletindo na compreensão dos princípios e funcionalidades destas tecnologias. O sistema proposto permite ler simultaneamente até 3 geradores termoelétricos, e é composto por dois principais circuitos eletrônicos: sendo um estágio aquisição de dados compostos por 3 canais para leitura de tensão, 3 canais para corrente e 6 canais para aquisição do sinal dos termopares (<400°C) além de sistema térmico que terá as funções de aquecimento e resfriamento. Os dados medidos são adquiridos para um computador com um software customizado a aplicação que permite o monitoramento das grandezas envolvidas (tensão, corrente, potência e temperatura) para acompanhamento do ensaio dos materiais termoelétricos, tanto por meio de uma indicação numérica como gráfica. O sistema de aquisição de dados possui precisa o para temperatura de ±2,5%, para tensão de ±2,5% e para corrente de ±1,5%. / The present work describes the development of a low cost didactic bench for Study of thermoelectric materials for performing obtaining performance curves testing of thermoelectric modules in regard to energy generation effect Seebeck and cooling via Peltier Effect order to disseminate knowledge in areas related to engineering schools, reflecting the understanding of the principles and features of these technologies. The proposed system can be read simultaneously up to 3 thermoelectric generators, and consists of two main electronic circuits: being a stage data acquisition composed of 3 channels for reading voltage and 3 channels for current using ACS712 instrumentation amplifiers and 6 channels signal acquisition thermocouples (<400 ° C) as well as thermal system will have the heating and cooling functions. The measured data is acquired to a computer with software developed in Delphi language, which allows monitoring of the quantities involved (voltage, current, power and temperature) to monitor the testing of thermoelectric materials, either through a digital display as a graphic . The data acquisition system has a temperature accuracy to ± 2,5% to ± 2.5% voltage and current of ± 1.5%.

O presente trabalho apresenta o desenvolvimento de uma bancada didática de baixo custo para estudo dos materiais termoelétricos para a realização de ensaios de obtenção de curvas de desempenho dos módulos termoelétricos no que se refere a geração de energia pelo Efeito Seebeck e resfriamento através do Efeito Peltier de forma a difundir os conhecimentos nas áreas afim em escolas de Engenharia, refletindo na compreensão dos princípios e funcionalidades destas tecnologias. O sistema proposto permite ler simultaneamente até 3 geradores termoelétricos, e é composto por dois principais circuitos eletrônicos: sendo um estágio aquisição de dados compostos por 3 canais para leitura de tensão, 3 canais para corrente e 6 canais para aquisição do sinal dos termopares (<400°C) além de sistema térmico que terá as funções de aquecimento e resfriamento. Os dados medidos são adquiridos para um computador com um software customizado a aplicação que permite o monitoramento das grandezas envolvidas (tensão, corrente, potência e temperatura) para acompanhamento do ensaio dos materiais termoelétricos, tanto por meio de uma indicação numérica como gráfica. O sistema de aquisição de dados possui precisa o para temperatura de ±2,5%, para tensão de ±2,5% e para corrente de ±1,5%. / The present work describes the development of a low cost didactic bench for Study of thermoelectric materials for performing obtaining performance curves testing of thermoelectric modules in regard to energy generation effect Seebeck and cooling via Peltier Effect order to disseminate knowledge in areas related to engineering schools, reflecting the understanding of the principles and features of these technologies. The proposed system can be read simultaneously up to 3 thermoelectric generators, and consists of two main electronic circuits: being a stage data acquisition composed of 3 channels for reading voltage and 3 channels for current using ACS712 instrumentation amplifiers and 6 channels signal acquisition thermocouples (<400 ° C) as well as thermal system will have the heating and cooling functions. The measured data is acquired to a computer with software developed in Delphi language, which allows monitoring of the quantities involved (voltage, current, power and temperature) to monitor the testing of thermoelectric materials, either through a digital display as a graphic . The data acquisition system has a temperature accuracy to ± 2,5% to ± 2.5% voltage and current of ± 1.5%.

Há pouca disponibilidade de informações de perda localizada de carga sobre conexões utilizadas em microirrigação. Diante disso, objetivou-se desenvolver e validar uma bancada automatizada para ensaios e determinar experimentalmente as perdas localizadas provocadas por conexões utilizadas em sistemas de microirrigação. Desenvolveu-se uma bancada automatizada utilizando um circuito eletrônico microcontrolado que dispõe de funcionalidades para aquisição e condicionamento de sinais de sensores; controle de inversor de frequência e válvula proporcional; controle Proporcional-Integral-Derivativo (PID); e, comunicação Modbus RTU com outros dispositivos através de rede RS-485. O firmware implementado no microcontrolador foi desenvolvido na linguagem C, enquanto que a interface gráfica do usuário (GUI) foi desenvolvida em C#. A metodologia de ensaios foi elaborada combinando recomendações de normas técnicas internacionais. Os ensaios foram conduzidos sob pressão de entrada controlada em 150 kPa, sendo ensaiadas entre cinco e dez peças para cada modelo de conexão. As curvas relacionando vazão e perda localizada de carga foram construídas com, pelo menos, 15 valores de vazão, submetidos sob condição de incremento e decréscimo para incluir eventuais efeitos de histerese do sistema de medição. Foram coletados 30 pontos por condição de vazão, tendo sido realizado uma aquisição de 900 pontos por ensaio. Para cada modelo avaliado foram apresentados as seguintes informações: curva de perda localizada de carga em função de vazão, coeficiente de perda localizada de carga (KL) e comprimento equivalente (Leq). A bancada de ensaios automatizada permitiu a condução dos ensaios onde os sistemas de medição e controle operaram adequadamente, sendo capazes de atender a requisitos estabelecidos em normas técnicas. Os valores aproximados de KL se apresentaram entre 2,70 a 24,08. Em muitos dos casos, o coeficiente tendeu a uma constância após um número de Reynolds de 10000. Pôde-se verificar também a sensibilidade do coeficiente relacionada com a razão das seções internas nas conexões. Os expoentes da vazão assumem valores próximos do que é aplicado pela equação de Darcy-Weisbach (m=2). / Information about minor losses caused by fittings employed in microirrigation systems are hard to be found in literature. The objective of this research was to develop and validate an automated bench for determine experimentally minor losses caused by fittings commonly installed in microirrigation. An automated bench was developed using a microcontrolled electronic circuit that has functionalities for data acquisition and signal conditioning; control of variable frequency drive and proportional valve; Proportional-Integral-Derivative Control (PID); and, Modbus RTU communication with other devices through a RS-485 network. The firmware implemented for the microcontroller was programmed in the C language, while the graphical user interface (GUI) was developed in C#. The methodology of tests was based on international standards. The tests were carried out under controlled inlet pressure, at 150 kPa, and five to ten units were tested for each fitting model. The curves relating flow and minor losses were drawn based on minimum of 15 flow values, obtained under conditions of increase and decrease of flow rate in order to take into account possible effects of hysteresis related to the measurement system. In each flow rate, 30 points were collected resulting in a sample size of 900 points in each test. For each model of fitting evaluated, the following information was presented: curves of minor losses as a function of flow rate, minor loss coefficient (KL) and minor losses expressed as an equivalent length (Leq). The automated test bench enabled to carry out the experiments properly, being able to meet the requirements established by technical standards. The values of KL presented ranged from 2.70 to 24.08. Usually, that coefficient tended to become constant for Reynolds number higher than 10000. The sensitivity of the coefficient related to a ratio of the internal sections in the connections was also verified. The flow exponents presented values close to what is applied by the Darcy-Weisbach equation (m = 2).