"Escapement mechanisms hold back a stream of parts driven either by mechanical or pneumatic means for a length of time and release a single part as required to an assembly station. They are used in most automatic multi-component assembly equipment. They occupy a significant design space and have dynamic characteristics of their own. This research aimed to develop a novel high speed mechanism for parts escapement that occupies less design space and contributes less to the dynamic activity of the structure. Several conceptual mechanisms were generated and evaluated. A compliant mechanism that amplifies the very small displacement of a piezo actuator was selected for detailed design. A proof of concept prototype was fabricated and tested. A piezo stack was used to bend a thin, spring steel, compliant beam. Its deflection was further amplified by attaching a comparatively rigid beam extension at the end of the compliant section. The mechanism escapes parts at 16 Hz using constrained layer damping on the beam to reduce vibrations. The concept is feasible to use on production machinery and provides advantages in terms of higher operating speeds and compactness. The concept could also be used where there is a requirement of high speed gating."

Digitized by Kansas Correctional Industries

Walking is an essential behavior across the animal kingdom. To navigate complex environments, animals must have highly robust, yet flexible locomotor behaviors. One crucial aspect of this process is the selection of an appropriate walking speed. Speed shifts entail not only the scaling of behavioral parameters (such as faster steps) but also changes in coordination to produce different gaits, and the details of how this switch occurs are currently unknown. Modulatory substances, particularly small biogenic amine neurotransmitters, can alter the output and even the connectivity of motor circuits. This work addresses the hypothesis that one such neuromodulator – serotonin (5HT) – is a key regulator of walking speed at the level of motor circuitry. To explore this question, I use the model organism Drosophila melanogaster which, like vertebrates, displays complex coordinated locomotion at a wide range of speeds. In Chapter 2, I will describe our efforts to characterize the anatomy of the serotonergic cell populations that provide direct input to motor circuitry. I find that innervation of the neuropil of the ventral nerve cord - a structure roughly analagous to the mammalian spinal cord - is provided primarily by local modulatory interneurons. Using stochastic single cell labeling techniques, I will detail the specific anatomy of individual neuromodulatory cells, and also the distribution of synapses across their processes. In Chapter 3, I will show that optogenetic activation or tonic inhibition of VNC serotonergic neurons produces opposing shifts in walking speed. To analyze behavior, I will use two complementary approaches. On the one hand, I will use an arena assay to holistically assess walking velocity and frequency. On the other, I will use a behavioral assay developed in the lab - the Flywalker - to assess walking kinematics at high resolution. The combination of these technique will give us a broad and specific picture of how the VNC serotonergic system modulates walking. In Chapter 4, I will identify natural behavioral contexts under which serotonin is used to shift walking behavior. I will use a variety of paradigms that induce animals to shift their speed, from changes in orientation and nutrition state, to pulses of light, odor, and a vibration. I will assess the requirement for the VNC serotonergic system under all of these conditions, to build a clearer picture of its role in modulating behavioral adaptation. In Chapter 5, I will describe our efforts, in collaboration with Pavan Ramdya's lab at EPFL, to functionally image VNC serotonergic cells while the animal is walking, to understand how activity is endogenously regulated in this population. Finally, in Chapter 6 I will characterize the circuit elements which might be responsible for serotonin's effect on walking. I will use recently developed mutant lines to identify the particular serotonergic receptors responsible for enacting shifts in walking behavior. Using genetic labeling tools, I will identify potential targets of serotonergic signaling in the VNC, and formulate a model by which action on these targets could adjust locomotor output. Altogether, this work seeks to characterize the anatomy and behavioral role of the VNC serotonergic system in Drosophila. I hope that through this work, I will gain a deeper understanding of not only this particular modulatory system in this particular behavioral context, but also of how static circuits are conferred with essential flexibility in behaving animals.

La gestion de la consommation d’énergie et de la température est devenue un enjeu crucial dans les systèmes informatiques. En effet, un grand centre de données consomme autant d’électricité qu’une ville et les processeurs modernes atteignent des températures importantes dégradant ainsi leurs performances et leur fiabilité. Dans cette thèse, nous étudions différents problèmes d’ordonnancement prenant en compte la consommation d’énergie et la température des processeurs en se focalisant sur leur complexité et leur approximabilité. Pour cela, nous utilisons le modèle de Yao et al. (1995) (modèle de variation de vitesse) pour la gestion d’énergie et le modèle de Chrobak et al. (2008) pour la gestion de la température. / Nowadays, the enegy consumption and the heat dissipation of computing environments have emerged as crucial issues. Indeed, large data centers consume as muse electricity as a city while modern processors attain high temperatures degrading their performance and decreasing their reliability.. In this thesis, we study various energy and temperature aware scheduling problems and we focus on their complexity and approximability. A dominant technique for saving energy is by prosper scheduling of the jobs through the operating system combined with appropriate scaling of the processor's speed. This technique is referred to as speed scaling in the literature and its theoretical study was initiated by Yao, Demers and Shenker (FOCS'1995). In order to manage the thermal behavior of a computing device, we adaopt the approach of Chrobak, Dürr, Hurand and Robert (AAIM'2008). The main assumption is that some jobs are more CPU intensive than others and more heat is generated during their execution. Moreover, the cooling of a computing device occurs by introducing appropriate idle periods.

Fifteen well-trained males, mid-thigh pull peak force (IPF 4403.61 ± 664.69N) and isometric peak force allometrically scaled (IPFa 226.04 ± 25.81) were assigned to two groups: repetition maximum training (RM) and relative intensity training (RI) for a twelve-week training intervention. The main effect of time showed a statistically significant difference in mean sprint performance and IPFa at the different time points (p < 0.001). There was a larger magnitude of within-subject effect with respect to sprint performance pre – post with the RI group (ES = 1.06, 7.19%) as compared to the RM group (ES = 0.567, 4.23%, p < 0.001), as well as a larger magnitude of within-subject effect with respect to IPFa pre – post with the RI group (ES = 0.426, 7.51%) as compared to the RM group (ES = 0.270, 13.29%). Furthermore, there was a non-statistically significant, moderate between-group difference in the change in IPFa from pre-post in favor of the RI group (ES=.75), and a large between-group difference in the change in sprint performance pre-post in favor of the RI group (ES=1.50). Results lead investigators to suggest the utilization of RI training tactics for the development of sprint performance when minimal sprint skill training is available.

abstract: Providing the user with good user experience is complex and involves multiple factors. One of the factors that can impact the user experience is animation. Animation can be tricky to get right and needs to be understood by designers. Animations that are too fast might not accomplish anything and having them too slow could slow the user down causing them to get frustrated. This study explores the subject of animation and its speed by trying to answer the following questions – 1) Do people notice whether an animation is present 2) Does animation affect the enjoyment of a transition? and 3) If animation does affect enjoyment, what is the effect of different animation speeds? The study was conducted using 3 prototypes of an application to order bottled water in which the transitions between different brands of bottled water were animated at 0ms, 300ms and 650ms. A survey was conducted to see if the participants were able to spot any difference between the prototypes and if they did, which one they preferred. It was found that most people did not recognize any difference between the prototypes. Even people who recognized a difference between the prototypes did not have any preference of speed. / Dissertation/Thesis / Masters Thesis Human Systems Engineering 2019

The awareness of electric power quality has increased over the past decade as electronic equipment has become more susceptible to power disturbances. The most disruptive power disturbances are voltage sags and momentary interruptions and their effect on adjustable speed drives (ASDs) is studied in this thesis. Several solutions have been suggested to provide only voltage sag ride-through to ASDs, but most solutions focus on ASDs with passive rectifiers since they hold the largest share of the market. This thesis focuses on ASDs with active rectifiers, which is an emerging and growing market due to the advantages of four quadrant operation and reduced harmonics offered. A solution is presented which provides an ASD with an active rectifier with the capability to ride through the most common sags in order to reduce the frequency at which the ASD trips and thereby increase its reliability. In order to provide ASDs with the capability to ride through momentary interruptions, it is necessary to interface an energy storage system to the ASD. Flywheels, ultra-capacitors and batteries are evaluated for use in an energy storage system to provide voltage sag and momentary interruption ride-through and a detailed comparison of six systems based on these technologies is presented. The interface circuit between the energy storage system and ASD has a significant influence on the performance of the energy storage system and therefore interface circuits to ASDs with passive and active rectifiers are studied. The addition of an ultra-capacitor energy storage system to an ASD with an active rectifier in order to provide ride-through of deeper sags and momentary interruptions is studied and a fuzzy logic controller is designed to enhance system performance. Initially, no communication between the ASD and the ultra-capacitor system is assumed and the ultra-capacitor system can therefore be added as a retro-fit to an existing ASD. It is, however, foreseen that the market for ASDs with ride-through capability of voltage sags and momentary interruptions will grow and the concepts for an integrated design of an ASD and an energy storage system are presented. / Graduation date: 1999

The continuing desire of industry to further improve process efficiency, through tighter control and energy conservation, has prompted users to pay closer attention to Adjustable Speed Drives (ASDs). The conventional ASDs consist of induction or synchronous motors controlled by power electronic controllers through the adjustment of supply frequency and line voltage. The drawback of these conventional ASDs lies in the high cost of the power electronic controllers which have the same rating as that of the machine itself. The Brush less Doubly-Fed Machine (BDFM) ASD has proven, both analytically and experimentally, to provide a cost effective and a wide range of precise speed control. The experimental BDFM prototypes built to date were designed and constructed individually based on designers' experience with self-cascaded machines. The success with these prototypes has promoted the idea of standardizing the design procedure for all future BDFMs. This thesis offers a general design procedure for the BDFM, which can serve as a first step in standardizing the manufacturing process of this machine. The procedure is presented in the form of a demonstration, by applying it to the design of a 60-hp, 600 to 900 r/min, 460-volts BDFM pump drive to replace the currently utilized conventional 60-hp wound rotor induction motor ASD. An ideal design, which determines machine details such as physical dimensions, slot specifics and conductor details based on conservative magnetic and electric loading assumptions, is one form of the design procedure. The other form, the practical design, involves utilizing a specified physical dimensions and slot details to determine the associated conductors' details and to insure the compliance of machine loadings with up-to-date industrial standards. In both procedures, the design will be made to satisfy, if not to exceed, the existing conventional drive performance. / Graduation date: 1994

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

In reduced speed zones, where no other cues indicate the need to slow down, drivers sometimes fail to notice the standard Speed Limit sign and may be speeding inadvertently. To help reduce inadvertent speeding, a red border was installed around the Speed Limit sign in seven reduced speed areas and the impacts of the increased conspicuity on speed limit compliance were measured. The general study approach was to collect and compare speed data for a standard sign (before condition) and a red border sign (after condition). The short-term effects of a modified red border sign, which was achieved by replacing the thin black border of the standard sign with a four inch wide red border, were evaluated at four sites. Results of this modified border study indicated that there was a statistically significant reduction in the mean speeds as well as in the 85th percentile speeds for the red border sign conditions, however the reductions were not practically significant. This study also evaluated the effect of using a higher conspicuity sheeting material at two sites. The results indicated that use of higher conspicuity sheeting has some benefits for the standard sign but no additional benefits for the red border sign. The added border study evaluated the long-term effects (approximately nine to eleven months after the treatment) of adding a three inch wide red border to the standard Speed Limit sign at three sites. The results of this study indicated that impacts of the red border treatment increase with passage of time. The mean speeds decreased by 8.1 percent and the percent of vehicles exceeding the speed limit (55 mph) decreased by 21.7 percent. The decreases in speeds were both statistically and practically significant. A comparison of the thesis study with other similar studies found in literature shows comparable benefits of the red border sign with other speed management measures. Based on the results for long-term effects, use of the red border Speed Limit sign is recommended in reduced speed zones where inadvertent speeding is common.