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Jonsson, Mattias. "The business value of demand response for balance responsible parties." Thesis, Uppsala universitet, Elektricitetslära, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-223803.
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By using IT-solutions, the flexibility on the demand side in the electrical systems could be increased. This is called demand response and is part of the larger concept called smart grids. Previous work in this area has concerned the utilization of demand response by grid owners. In this thesis the focus will instead be shifted towards the electrical companies that have balance responsibility, and how they could use demand response in order to make profits. By investigating electrical appliances in hourly measured households, the business value from decreasing electrical companies’ power imbalances has been quantified. By an iterative simulation scheme an optimal value was found to be 977 SEK/year and appliance. It could however be shown that the value became larger for energy inefficient households, and that such consumers’ participation in a demand response market would be prioritized ahead of other measures like isolating walls is rather unlikely. Thermal appliance whose load depend on the outdoor temperature are less valuable for demand response during the summer months, and the annual value would increase if less seasonally dependent appliances were used. Additionally, by increasing the market price amplitudes and the imbalance price volatility, it could be shown that the potential for such demand response markets is larger in e.g. the Netherlands and Germany.
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Qutishat, Dania. "Balance and response time in patients with chronic tennis elbow." Thesis, Sheffield Hallam University, 2011. http://shura.shu.ac.uk/20786/.
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Tennis elbow is a common condition that is easy to diagnose however, the optimal approach to management is still an area of considerable debate with limited evidence to support current practice. This is due to the ambiguous nature of its aetiology and pathology, which remain poorly understood. Bilateral sensorimotor deficits in the upper limb have been found in patients with unilateral tennis elbow, as they had slower response time and slower speed of movement. Research suggests that these patients could also have generalised sensorimotor deficits due to peripheral and central sensitisation. However, only bilateral sensorimotor deficits have been investigated suggesting that research is warranted to investigate the generalised sensorimotor deficits in patients with chronic tennis elbow. Therefore, it is the intention of this research to provide new knowledge in the area of sensorimotor function in these patients. This PhD programme consisted of two phases, the first phase involved healthy participants (n=22) and the second phase involved patients with chronic tennis elbow (n=11). This study was quasi experimental and investigated sensorimotor function by measuring balance and response time of the upper and lower limbs. The outcome measure for balance was time to boundary (TtB) in the anterio-posterior (ap) and medio-lateral (ml) directions. For the response time, the outcome measures were 1-choice response time and 2-choice response time. The test-retest reliability was assessed for these outcome measures using the intraclass correlation coefficient (ICC) and the standard error of measurement and yielded good to excellent reliability estimates. Following descriptive analysis and tests for normality and homogeneity of variance, the data was analysed using a mixed design ANOVA. Results showed that patients with chronic tennis elbow have more balance instability when compared to healthy participants as they were closer to reach their stability boundary in the anterioposterior direction. The findings of this research add new knowledge to the field of sensorimotor function in patients with chronic tennis elbow and enhance the understanding of this condition between health professionals.
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Gormley, Sheena Mary Catherine. "Plasma and urinary cytokine balance and renal function during cardiac surgery." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326410.
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Connysson, Malin. "Fluid balance and metabolic response in athletic horses fed forage diets /." Uppsala : Dept. of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/11444465.pdf.
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Huh, Ravina (Eunhye). "Balance control in dance positions." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/23054.
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The purpose of this thesis is to develop and understand dance balance characteristics on various kinds of dance, related positions and shoe types which contribute to dance performance and to understand different balance controls in various groups. The first study was conducted to examine balance into ballet 2nd position between Ballet shoes and Pointe shoes. Eight dancers performed five different conditions in ballet 2nd position (Ballet Flat, Ballet Demi, Pointe Flat, Pointe Demi, and Pointe Toe) and Centre of Pressure (COP) was used to assess balance. The second study was testing balance control and response to perturbations whilst standing on double leg stance dance positions using a moving platform. Four dance positions were performed by eight subjects (Normal Flat, Turnout Flat, Normal Demi and Turnout Demi) and the platform was moved in two different directions (Forward and Backward) at two different speeds (slow and fast). Kinetics, Kinematics and EMG data was taken from this study. The third study was taken to compare balance control and response to perturbations in single leg standing dance positions between eight dancers and eight gymnasts. The subjects performed static single leg balance in Normal Flat, Turnout Flat, Normal Demi and Turnout Demi. Also, perturbed stance trials were collected in anterior, posterior, right and left directions for two dance positions (Normal Flat and Turnout Flat) at two different speeds (slow and fast) on the moving platform. The results from the studies indicate that dancers move in Medial - Lateral direction more than in Anterior - Posterior direction on Demi-pointe and Toe standing by performing plantar flexion during ballet 2nd position. Demi-pointe position may cause longer delay of EMG latencies because CNS is probably sending information already to keep correcting balance on Demi-pointe. Dancers and Gymnasts have different balance controls due to their ways of training in their performance. Dancers generally reacted faster with slow perturbation in Turnout stance than Gymnasts because this is the particular condition which Dancers are training in.
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McLaughlin, Ruth. "Lifestyle modifications associated with regulation of the energy balance response to exercise." Thesis, University of Strathclyde, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415301.
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Miller, Emily Michele. "Effects of Obesity on Balance Recovery in Response to Small Postural Perturbations." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35465.
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Obesity is a major and growing health concern associated with an increased risk of falls. The majority of falls are thought to result from some kind of postural perturbation, yet the biomechanical mechanisms as to why obese individuals fall more often is unclear. Therefore, the goal of this study was to investigate the effects of obesity on balance recovery in response to small forward postural perturbations. Twenty male participants, including 10 lean (mean BMI ± SD: 21.9 ± 1.4) and 10 obese (BMI: 33.2 ± 2.3), were exposed to two types of postural perturbations (force impulses applied with a pendulum and angular displacements administered with a release mechanism). Participants attempted to recover balance with only an ankle strategy such that neither a step nor hip flexion was utilized. Quiet standing trials were also conducted for comparison with the literature. Obese individuals exhibited less center of mass (COM) displacement and a slower COM velocity compared to lean individuals when exposed to identical force perturbations. When exposed to the force perturbations relative to body weight, and when released from identical lean angles, no differences in COM performance were found. During quiet standing, no differences in center of pressure (COP) velocity were observed between obese and lean groups. In all tasks, the obese generated higher ankle torque than the lean. Overall, the obese participants exhibited no differences in movement or less/slower movement than the lean participants when recovering from small forward postural perturbations as well as during quiet standing. These results imply that obesity in young adult males did not impair balance recovery for the tasks investigated.Master of Science
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Seaman, Brandi S. "Evidence for the Bypass of the Response-Selection Bottleneck in Tasks with Reflexive Responses in Younger and Older Adults." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/scripps_theses/159.
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This study investigated dual-task processing in younger and older adults using a psychological refractory period procedure. The first task was to name the color framing a picture; the second task was to either press a button or tilt their body in the direction of the tilt of the picture. In the body-tilt condition, electromyography was used to determine the reaction time. The stimulus-onset asynchrony (SOA) between the onset of the color and tilting of the picture varied from 50 to 1000 ms. In contrast with the response selection bottleneck model, which claims that processing of a second task cannot be completed until the first task is finished, the mode of response for the two tasks directly impacted the ability to avoid the bottleneck. In the body-tilt condition the increase in reaction time to the second task with decreasing SOA was less than in the button press condition, suggesting that processing of the second task could begin before processing of the first task was completed. This was true for both younger and older adults. Contrary to previous findings that older adults cannot engage in simultaneous processing of two tasks, evidence was found that older adults, like younger adults, could bypass the cognitive bottleneck if the second task has a reflexive component.
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Grill, Rebecca. "Market potential for using demand response from heat pumps in multi-family buildings." Thesis, Uppsala universitet, Fasta tillståndets fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354873.
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More renewable energy leads to higher energy imbalances in the Swedish electric power system. In the same time, the grid capacity is almost reached in some regions which requires an extension of the current grids or a reduction of the power consumption. Demand response could be a key factor for both stabilizing the energy balances and reducing the grid congestion. The aim with this thesis is to analyze the potential incomes that demand response from heat pumps can generate for the balance responsibility parties and the grid operators and evaluate how it would affect the end-consumers. The investigated local grid that contains of 174 multi-family buildings with heat pumps could reduce its highest peak power with 2,9 MW. This peak power reduction generated a cost reduction of 483 000 SEK per year or 2800 SEK per building per year in reduced penalty fees and power subscription fees. The mFRR market and the power reserve market were determined to be the most suitable markets for using demand response from heat pumps on for the balance responsibility party in the electricity price region SE3. SE3 consists of 10146 multi-family buildings with heat pumps. The mFRR market generated an average income of 2 699 000 SEK per winter season whereas the power reserve market generated a yearly administrative compensation of 1 133 000 SEK per season and 104 000 SEK per call-off. It is important that end-consumers obtain demand-based tariffs or hourly based tariffs to enable a cost reduction from the control system.
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Karlsson, Olof Magnus. "Predicting Ecosystem Response from Pollution in Baltic Archipelago areas using Mass-balance Modelling." Doctoral thesis, Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-144120.
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Baltic archipelago areas have high nature values despite being polluted from various antrophogenic activities within the Baltic Sea catchment area and from long-range transport of airborne substances. The discovery of environmental problems in the Baltic Sea in the 1960s led to countermeasures that gradually gave results in reducing the toxic pollution, e.g. from PCBs. Today, much of the environmental management is focused on reducing the effects of eutrophication. There is a demand from society on science to develop strategies that can direct remedial actions so that the cost-effectiveness is maximised. This work focuses on how mass-balance models can be used to understand how coastal ecosystems are controlled by abiotic processes and to predict the response to changes in loading of different substances. Advection, sedimentation and burial are examples of general transport processes that are regulated by morphometrical characteristics, e.g. size, form, effective fetch and topographical openness. This is why different coastal areas have different sensitivity to loading of pollutants. A comparison of six phosphorus and chlorophyll models of different complexity showed that the model performance was not improved with more state variables of total phosphorus (TP) than two water and two sediment compartments. Modelling chlorophyll as a separate state variable did not improve the results for individual values compared to a simple regression against total phosphorus in surface water. Field investigations of the phosphorus content in accumulation sediments along the coast of Svealand showed a distribution pattern that probably is related to differences in the redox status. The average content of mobile phosphorus was much higher than previously found in offshore Baltic sediments indicating that sediments may play an important role for the phosphorus turnover in Baltic archipelago areas. A one-year field study to measure the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in water, sediments and fish during different seasons was carried out in Kallrigafjärden Bay. The collected data set was used to test a mass-balance model for PCCD/F-turnover. It was possible to reproduce the concentrations of different PCDD/F-congeners with high accuracy using a general model approach, including one water compartment and two sediment compartments, indicating that the applied model has the necessary qualifications for successful predictions of PCDD/F-turnover in Baltic coastal areas.Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 736
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Kovarik, Johanna. "Storm Response and Water Balance of Temperate Rainforest Karst Watersheds: Tongass National Forest, Alaska." TopSCHOLAR®, 2007. http://digitalcommons.wku.edu/theses/430.
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The Tongass National Forest in southeast Alaska contains 2,176 square kilometers of karst. As part of the evolving Tongass Land Management Plan, research into the function of karst systems is crucial in understanding how forest management affects not only karst areas but also surrounding ecosystems. Dye trace and water balance results in two watersheds on the north end of Prince of Wales Island demonstrate the difficulty in containing the effects of management, as water can enter karst catchments from unknown sources at different flow regimes. A dye trace was conducted in Windgate and Canyon Block watersheds. Two sinking streams were traced to one resurgence spring in Canyon Block, and four sinking streams were traced to one resurgence spring in Windgate. Water balance data calculated for the entire study period and individual storm events suggests that Windgate has been sufficiently delineated. Data from the study period and storm event water balance calculations for Canyon Block suggest that at high flow discharge is pirated into Canyon Block from another system. High resolution monitoring in each catchment show that there is no significant delay between the increase in discharge and the arrival of direct runoff, as evidenced by the quick decrease in specific conductance. This could result in a quick transmission of sediment and contaminants through the karst system into downstream salmon habitat.
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de, Woul Mattias. "Response of glaciers to climate change : mass balance sensitivity, sea level rise and runoff /." Stockholm : Department of Physical Geography and Quaternary Geology, Stockholm university, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7521.
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Arribas-Douglas, Miramelinda Badri. "China's Response to Disputes in the South China and East China Seas." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449844399.
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Campbell, Adam Donald. "Insights into human dynamic balance control : postural response initiation explored through classical conditioning and startle." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43307.
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As a scientific discipline, dynamic posturography aims to understand the neurological and biomechanical mechanisms that contribute to postural stability and corrective postural responses (PRs). The main focus of this thesis was to better understand the neurophysiology of corrective PRs that prevent falls that emerge from external forces applied to the body by balance perturbations. In a sequence of 4 studies, this thesis utilized novel applications of established techniques (classical conditioning and startle paradigms) to address questions regarding the role of sensory feedback in PRs initiation and the nature of PRs that are evoked by balance perturbations. The first of 4 experiments tested the link between sensory feedback derived by balance perturbations and PR initiation by attempting to trigger PRs using auditory cues that, prior to classical conditioning provided no relevant information pertaining to balance perturbations or postural stability. The second study examined the extent to which conditioned PRs may exist as prepared motor behaviours that could be initiated by startling acoustic stimuli in the absence of balance perturbations. The third study attempted to extend the previous findings of PR motor preparation into a more ecologically valid scenario involving unexpected balance perturbations. The fourth and final study in this thesis examined whether startle responses could contribute to first-trial effects observed on PRs evoked by the first in a repeated sequence of balance perturbations.
Individually, each study provided highly novel contributions to the field of dynamic posturography. However, when taken together, they provide novel insight into both the mechanisms involved in PR initiation and the understanding of reactions evoked by balance perturbations.
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Mohd, Sukri Nursyuhada. "Influence of hyperthermia and antioxidant supplementation on redox balance and heat shock protein response to exercise." Thesis, University of Bath, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.767577.
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Physical activity of moderate intensity and duration leads to healthy biological adaptations in humans. However, very intense and prolonged exercise may induce disruption in redox balance, potentially increasing oxidative stress. In addition, exposure to environmental heat stress and associated hyperthermia further increases oxidative stress and may induce the expression of heat shock proteins. However, antioxidant supplementation is believed to minimise the effect of oxidative stress and may therefore help reduce or limit the heat shock response to exercise heat stress. The first study (Chapter 4) examined whether exertional heat illness (EHI) casualties among military recruits may exhibit greater disturbances in redox balance following exercise compared to non-EHI controls. Nine (n=9) recruits were identified as having suspected EHI during the Loaded March (LM) on day 1, with a peak mean (SD) body core temperature of 40.1 (0.5) °C. Fifteen (n=15) recruits were identified as having suspected EHI during the Log Race (LR) on day 2, with a peak mean (SD) body core temperature of 39.7 (0.5) °C. A further twenty-one (n=21) recruits, which successfully finished both LM and LR events, were treated as controls (CON). Interestingly, the plasma antioxidant concentration was significantly elevated from pre to post-exercise (p < 0.001) for EHI and CON groups, during both LM and LR events, with no changes on lipid peroxide protein carbonyl concentrations. These data suggest there is no increase in lipid peroxide or protein carbonyl level damage in response to intense hyperthermic military exercise, regardless of acute heat illness. It is possible that military training augments the body's defence capabilities, thus reducing oxidative stress and damage induced by free radical production. To date there is a scarcity of data examining the effects of acute intake of antioxidant supplements on oxidative stress and heat shock response during continuous exercise in a hot environment. Hence, the aims of the second study (Chapter 5) were to examine the effects of acute ingestion of Quercetin (Q), Quercetin + vitamin C (QC) or placebo (P) 14 hours before, 2 hours before and every 20 minutes during trials on oxidative stress and heat shock response. In this randomised, crossover study 10 recreationally active males (age 21±2 y, V̇ O2max 54.9±8.4 ml.kg.min-1) completed three running trials at 70% V̇ O2max for 60 minutes in the heat (33.0±0.3°C; 28.5±1.8% relative humidity). Exercise heat stress significantly elevated plasma quercetin (p=0.02), antioxidant power (FRAP) (p < 0.001),plasma heat shock protein 70 (HSP70) (p=0.009) and plasma heat shock protein 90α(HSP90α) (p < 0.001) over time, but no differences were detected between trials. Also, no changes were observed in protein carbonyl concentration. Acute intake of quercetin significantly increased the level of plasma quercetin however, this did not affect the plasma antioxidant capacity or heat shock response to exercise heat stress. The increases in plasma HSP70 and HSP90α concentrations might act as supplementary antioxidants, reducing the oxidative damage reflected in the absence of changes in protein carbonyl. Exercise heat stress is effective in inducing both intracellular HSP70 (muscle and peripheral blood mononuclear cell (PBMC)) and extracellular HSP70 (plasma) concentrations. Thus, the third study (Chapter 6) tested the hypothesis that this acute quercetin supplementation would induce similar trends in plasma HSP70 and intracellular HSP70 concentrations 2 days following exercise heat stress. In this randomised, crossover study, 9 recreationally active males (age 22±2y, V̇ O2max 50.3±3.3ml.kg.min-1) completed three running trials at 70% V̇ O2max for 60 minutes in the heat (32.9±0.3°C; 28.3±1.2% relative humidity). This study demonstrated that there is no positive relationship between both intracellular of HSP70 (muscle and PBMC) and plasma HSP70 (eHSP70) 2 days following exercise heat stress. These data suggest that the release of eHSP70 could originate from others tissue or cells. Additionally, the absence of differences between trials in the expression of muscle HSP70, PBMC HSP70 and plasma HSP70 might indicate it is implausible that quercetin might inhibit the expression of HSP70 in plasma, muscle and PBMC 2 days following the exercise heat stress stimulus. Overall, the results from this thesis emphasise that the hyperthermia experienced in response to exercise and environmental heat stress could potentially influence the human redox response and heat shock response. Besides, there is reasonable evidence that acute quercetin co-ingestion with vitamin C has the potential to improve the bioavailability and bioactive effects of quercetin, however, the effects of quercetin supplementation in reducing oxidative stress in response to exercise heat stress remains to be elucidated. In addition, the anti-oxidative ability of acute ingestion of quercetin to suppress the intracellular and extracellular heat shock response remains uncertain and worthy for further investigation.
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Parker, Heidi M. "The effect of negative sponsor information and team response on identification levels and consumer attitudes." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1180025349.
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Salinas, Alexander A. "Effects of subconcussive head impacts on cerebral acoustic response, oculomotor function, and balance in high school athletes." Thesis, University of Delaware, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1562420.
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There is an increasing amount of evidence indicating potentially devastating long-term effects of subconcussive impacts in the absence of clinical symptoms of concussion in high school football players.
Purpose: To determine whether subconcussive head impacts produce any immediate cognitive, postural, and physiological changes after athletic participation.
Methods: Fifty-nine interscholastic football (FB), soccer (SOC), and track (RUN) athletes provided baseline and post-participation data. Four cerebral acoustic response variables were examined using the Brain Acoustic Monitor (BAM) (Active Signal Technologies, Linthicum Heights, MD). Oculomotor function was assessed via the King-Devick (K-D) test. Balance was evaluated using a computerized version of the Balance Error Scoring System (BESS).
Results: Significant changes in left-brain ratio were observed in football players postgame (p = 0.023). Between-group analysis of baseline data for left- and right-brain divergence noted differences as well (FB vs. SOC, p = 0.012, p = 0.008, respectively; FB vs. RUN, p < 0.001, p < 0.001, respectively). There were no significant differences with either oculomotor or balance variables.
Conclusions: One game may not provide enough head impact exposure to elicit detectable changes with the utilized instrumentation. Unexpectedly, there were differences observed in football players' baseline BAM scores in the absence of significant differences in baseline and post-participation K-D test and BESS scores across all groups, possibly indicating that prior exposures to subconcussive impacts in this cohort of football players may be present.
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Kwon, Ju Youn. "Human responses to outdoor thermal environments." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/5519.
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This thesis presents a series of studies into the responses of people to outdoor thermal conditions experienced over all seasons in the United Kingdom. The aim was to investigate practical methods for predicting human responses to outside weather conditions, which would be useful in predicting effects on human comfort and health. The studies involved both laboratory experiments and field trials. One particular aspect of outside conditions, not usually investigated in laboratory studies, is the contribution of solar radiation. Single subject and thermal manikin studies were used to determine the contribution of solar radiation to human response. In addition to this, a total of 168 subjects responses were recorded during trials at the Loughborough University weather station compound. (latitude 52.47N and longitude 01.11W). The trials were distributed between July 2007 and October 2008. This provided a comprehensive data-base for the evaluation of thermal indices. The thesis is divided into four parts. Part one provides an introduction to the subject and a comprehensive literature review. It also describes equipment, calibration procedures and methods used. Part two quantified the contribution of solar radiation to the heat load on a person. A human subject and a heated thermal manikin were exposed to outdoor thermal conditions, while in light clothing and (for the person) conducting a step test. They were then exposed to identical conditions in a thermal chamber, but without the contribution of the sun. The conditions outside were 23˚C air temperature, 42˚C mean radiant temperature and 54% relative humidity with an average air velocity of 0.75 ms-1. The difference in sweat rate (person) and heat required (manikin) between outdoor and indoor conditions were used to estimate the contribution of the sun. Using three different analyses estimates were 14 Wm-2, 35 Wm-2 and 50 Wm-2 depending upon the assumptions made. Part three describes current thermal indices that can be used to assess the effects of weather conditions on people. It also presents the results of weather station measurements over the time period considered. In chapters 8 and 9 field trials are described which capture both the thermal conditions and human physiological and subjective responses to those conditions. Chapter 10 uses the data collected to provide an evaluation of current thermal indices for predicting human responses. The range of air temperature and relative humidity (at 2 pm) over a year was -2˚C to 29˚C and 34% to 95% respectively. Wind speed varied and was greater in winter and spring than in summer and autumn. Solar radiation was influenced by the altitude of the sun which depended upon season. Mean solar radiation increased from December to June and decreased from June to December. The subjective and physiological responses for 130 people (65 males and 65 females) over a range of outdoor weather conditions are presented. Physiological responses for females generally showed a stronger relationship with environmental variables and subjective responses than those for males. The subjective and physiological responses of four groups (one in each season of the year - involving a total of 38 people), are presented. It was found that there were significant individual differences in response. Part four provides a suggestion for an improved thermal index. The PMV (Predicted Mean Vote) out of four thermal indices (WBGT, PMV, WCI/tch and Twc) had the strongest relationship with environmental variables and physiological responses but had a weak relationship with subjective responses. A PMVoutdoors index was developed to improve the prediction of subjective responses for the outdoor conditions investigated. Conclusions and recommendations for future research are provided.
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Bosso, David Raymond. "The land of steady habits and the land of the rising sun : Connecticut's response to the perceived Japanese economic threat, 1980-2000 /." Abstract Full Text (HTML) Full Text (PDF), 2008. http://eprints.ccsu.edu/archive/00000520/02/1968FT.htm.
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Thesis (M.A.) -- Central Connecticut State University, 2008.Thesis advisor: Mark Jones. "... in partial fulfillment of the requirements for the degree of Master of Arts in History." Includes bibliographical references (leaves 152-169). Also available via the World Wide Web.
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Larsen, Elisabeth K. "Transpiration patterns of Pinus halepensis Mill. in response to environmental stresses in a Mediterranean climate." Doctoral thesis, Universidad de Alicante, 2021. http://hdl.handle.net/10045/116474.
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Increased frequency of severe drought events, coupled with rising air temperatures and vapor pressure deficits (VPD), pose a great threat to Mediterranean forests. Pinus halepensis Mill. is one of the most widespread species in the countries surrounding the Mediterranean basin. Thus, water use of this species plays a critical role in the regions water balance. Studying transpiration patterns and the mechanisms behind stomatal responses to the combined effects of changing VPD and soil moisture can help us improve estimation of forest water use in a changing climate. To improve the estimation of forest evapotranspiration in the Mediterranean basin, the objective of this thesis is to evaluate the transpiration patterns of Pinus halepensis and the role of this species in the soil-water balance under different environmental conditions. Two pine forests in the Turia river basin, eastern Spain, were monitored over a two-year period. The two locations were selected at contrasting altitudes and distances to the sea but within the same hydrological basin, to evaluate if this placement would change the relationship between environmental conditions and the water use of the pines. Sap flow measurements were obtained on a 30-minute interval together with soil moisture measurements and meteorological variables. A soil-water balance was performed on a forest plot-level using an eco-hydrological model in combination with the transpiration data, to assess the contribution of pine transpiration to actual evapotranspiration. Transpiration was dictated by changes in VPD, relative extractable water (REW) and the interaction between these two variables at both sites, indicating that the pines depended on water in the shallow soil layers, and this was restricted during large parts of the year. Except for low winter temperatures having a decreasing effect on transpiration only at the inland site, no significant differences were found in the relationship between environmental drivers and transpiration patterns between the two sites. Using a predictive model, sap flow was shown to be restricted on days of mean VPD values of 2.5 kPa, even when soil moisture levels were relatively sufficient (REW = 0.30), indicating a VPD threshold that decreases pine transpiration. This could potentially affect performance and survival of the species with predicted increases in air VPD. Transpiration levels were highly restricted throughout the first year demonstrating that physiological stresses were not limited to summer months. Using two-year old seedlings in an experiment under controlled conditions confirmed that high levels of VPD can have a decreasing effect on transpiration of P. halepensis (in response to instant changes from 1.5 kPa to 2.7 kPa), while there is an intermediate VPD range that increases transpiration (between 1.0 kPa – 1.5 kPa). This demonstrate how important it is to incorporate VPD changes when predicting forest water use under future climatic changes. Combining transpiration data with eco-hydrological modelling demonstrated that transpiration levels accounted for 62% of total ETa levels during two years of study. Interception levels where 32% of gross precipitation, representing a large water loss to the forest ecosystem. With increased frequency of drought events, soil moisture levels are predicted to become even more limited. Together with a rise in temperatures and consequently VPD, transpiration and growth are likely to be constrained.
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Birch, Gary J. "Evidence for adaptive differences in the ontogeny of osmoregulatory ability, current response and salinity preference of coho salmon, Oncorhynchus kisutch from coastal and interior populations." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26169.
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This thesis examines the ontogeny of plasma sodium regulation (an indicator of osmoregulatory ability), current or rheotactic response (an indicator of emigration timing) and salinity preference in juvenile coho salmon (Oncorhynchus kisutch). The purpose of the study was to determine if there are inherited differences in the development of these traits between coastal and interior British Columbia populations of coho. An interior (Cold water River) and a coastal (Rosewall Creek-Big Qualicum River) population were monitored for the above traits throughout the year. Both wild and laboratory groups were included in the study. The laboratory raised populations were divided into two incubation treatment groups: one incubated under a coastal temperature regime, and the other incubated under an interior temperature regime.
There were no differences in the development of sodium regulatory ability between wild populations when the data were sorted by coho weight. Coastal coho, however, physiologically smolted after one year in the natal streams, while interior coho smolted after at least two years of freshwater growth. No obvious differences were noted between wild resident populations in the timing of downstream movement or the shift in salinity preference from hypotonic to isotonic and hypertonic salinities. Both of these behavioural responses typically occurred in the spring (April-May) of each year. Fyke net catches, however, sugqested that, in addition to the spring emigrations observed in both populations, a portion of the interior population migrated in the fall (November). No differences in the development of sodium regulatory ability were observed either within or between laboratory raised populations. Ion regulatory ability increased to a plateau in the fall and winter following emergence, and increased to smolting levels during the following spring (April-May). There were differences between coastal and interior populations in the pattern of development of both nocturnal current responses and the preference for isotonic or hypertonic salinities. Interior laboratory raised coho developed negative nocturnal rheotaxis and a preference for isotonic salinities about three months earlier (November) than laboratory raised coastal coho (late February-March). Within populations, no differences were observed in the ontogeny of these traits in the groups reared under different temperature regimes.
Because these interpopulation ontogenetic behavioural differences persisted in fish reared under identical laboratory conditions, they probably have some genetic basis. Such an innate component in behaviour implies an adaptive role and in juvenile coho these behavioural traits may allow populations to use a variety of habitats at different distances from the sea, even though a major physiological schedule (in this case the development of ion regulatory capabilities) appears to be fixed within the species. Perhaps variations in migratory timing and salinity preference in juvenile coho evolved to assure survival in a relatively unstable and often severe environment by optimizing habitat use within the constraints of an overriding physiological schedule.Science, Faculty of
Zoology, Department of
Graduate
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Buchanan, Margaret MacNeill. "Soil Water Flow and Irrigated Soil Water Balance in Response to Powder River Basin Coalbed Methane Product Water." Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/buchanan/BuchananM0505.pdf.
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A repacked soil columns experiment and a series of computer soil water balance simulations were conducted to examine potential impacts of coalbed methane (CBM) water from Montana's Powder River Basin (PRB) on soil water flow and water balance in PRB soils. CBM water is often high in sodium, which may separate soil clay particles, particularly after soil exposure to low-salinity rainfall or snowmelt, and when soils contain expansible smectite clay minerals. Aggregates in soils exposed to sodic water may swell and slake, and clays and other fine particles may disperse, clogging soil pores and slowing or preventing soil water flow. In the soil columns experiment, A and B horizon materials from sandy loam, silt loam, and clay loam soils were pre-treated with water having salinity and sodicity typical of PRB CBM water or of Powder River (PR) water currently used for irrigation in the basin. Tension infiltrometer measurements were used to determine infiltration flux, first using pre-treatment water, and subsequently deionized (DI) water, simulating rainwater. Measurements were compared by pre-treatment water, horizon, and soil type. Under pre-treatment water testing, the sandy loam and clay loam soils pre-treated with CBM water exhibited smaller infiltration flux values than when pre-treated with PR water. Only the sandy loam soil showed a greater decrease in infiltration flux with DI water on soils pre-treated with CBM relative to PR water pre-treated soils. There was no difference in infiltration flux decrease with DI water between A and B horizon soils, or between smectite and non-smectite soils. The soil water balance numerical simulations modeled potential effects of sodic irrigation waters on sandy loam, silt loam, clay loam and silty clay PRB soils under sprinkler or flood irrigation, during one growing season. Baseline soil water retention functions were constructed for the five soils, and adjusted via trends identified in the literature to create five additional functions for each soil, simulating exposure to five increasingly sodic irrigation waters. Simulation results showed greater impact of sodic irrigation under flood than sprinkler irrigation. The fine sandy loam and silty clay loam soils exhibited the fewest changes in water balance partitioning, while the silt loam and silty clay soils showed the greatest changes, especially in increased runoff and reduced transpiration.
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Warnke, Arne Jonas [Verfasser], and Bernd [Akademischer Betreuer] Fitzenberger. "Essays on gender differences in training, incentives and creativity, survey response, and competitive balance and sorting in football." Freiburg : Universität, 2017. http://d-nb.info/1135575673/34.
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Davidson, Bradley. "Experimental and simulation-based assessment of the human postural response to sagittal plane perturbations with localized muscle fatigue and aging." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/29361.
Full textAbstract:
Falls from heights (FFH) are one of the leading causes of fatalities in skilled labor divisions such as construction, mining, agriculture/forestry, and manufacturing. Previous research has established that localized muscle fatigue (LMF) increases center of mass (COM)- and center of pressure (COP)-based measures of quiet stance. This is important because these increases have been linked to elevated risk of falls, and workers in the construction industry frequently engage in fatiguing activities while working at heights. In addition, the rate of fatality due to an occupational fall increases exponentially with age. Improved methods of fall prevention may be obtained through increased understanding of factors that have a deleterious effect on balance and postural control such as LMF and aging.
An initial study was conducted to investigate the effects of LMF and aging on balance recovery from a postural perturbation without stepping. Sagittal plane postural perturbations were administered to young and older groups of participants before and after exercises to fatigue the lumbar extensors or ankle plantar flexors. Measures of balance recovery were based on the COM and COP trajectories and the maximum perturbation that could be withstood without stepping. Balance recovery measures were consistent with an LMF-induced decrement to recover from perturbations without stepping. Aging was also associated with an impaired ability to recover from the perturbations.
The second study in the series investigated the effects of aging and LMF on the neural control of upright stance during small postural perturbations. Small magnitude postural perturbations were administered to young and older groups before and after fatiguing exercises. A single degree of freedom (DOF) model of the human body was developed that accurately simulated the experimentally collected kinematics during recovery from the perturbations. The model was controlled by invariant feedback gains that operated on the time-delayed kinematics. Feedback gains and time-delay were optimized for each participant, and a novel delay margin analysis was performed to assess system robustness toward instability. Results indicated that older individuals had a longer "effective" time-delay and exhibited greater reliance on afferent velocity information. No changes in feedback controller gains, time-delay, or delay margins were found with LMF in either age group.
The final study investigated the use of a nonlinear controller to simulate responses to large magnitude postural perturbations. A three DOF model of the human body was developed and controlled with the state-dependent Riccati equation (SDRE). Parameters of the SDRE were optimized to fit the experimentally recorded kinematics. Unlike other forms of nonlinear control, the SDRE provides meaningful parameters for interpretation in the system identification. The SDRE approach was successful at stabilizing the dynamical system; however, accurate results were not obtained. Reasons for these errors are discussed, and an alternative formulation to the time-delayed optimal control problem using Roesser state space equations is presented.Ph. D.
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Suwansawat, Suchatvee 1972. "Earth pressure balance (EPB) shield tunneling in Bangkok : ground response and prediction of surface settlements using artificial neural networks." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/32222.
Full textAbstract:
Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2002.Vita.
Includes bibliographical references.
Although Earth Pressure Balance (EPB) shields have been used for several decades, very little information exists about the actual mechanisms of shield-ground interaction. The ground response mechanism induced by EPB tunneling is difficult to understand, because this requires not only reliable ground deformation measurements in the field but also operational records of the shield. Numerous empirical and analytical relations between characteristics of traditional shields and surface and subsurface deformations exist; also 2-D and 3-D numerical analyses have been applied to such tunneling problems. However, very few approaches have been developed for EPB tunneling. This research makes use of the fact that in the Bangkok MRTA project, data on ground deformation and shield operation were collected. The tunnel sizes are practically identical and the subsurface conditions over long distances are comparable, which allow one to establish relationships between ground characteristics and EPB-operation on the one hand, and surface and subsurface deformations on the other hand. A computerized database, which records much of the information on a ring-by-ring (1.2 meter interval) basis, was developed for this purpose. After using the information to identify which ground- and EPB-characteristic have the greatest influence on ground movements, an approach based on Artificial Neural Networks (ANN) was used to develop predictive relations. Since the method has the ability to map input to output patterns, ANN enable one to map all influencing parameters to surface settlements.
(cont.) Combining the extensive computerized database and the knowledge of what influences the surface settlements, ANN can become a useful predictive method. This research attempts to evaluate the potential as well as the limitations of ANN for predicting surface settlements caused by EPB shield tunneling and to develop optimal neural network models for this purpose. Specifically, this involves settlement predictions over the tunnel axes of single and twin tunnels; together with other interpretations, it is also possible to predict settlement troughs. Other shield effects such as lateral deformation and liner deformation of the first tunnel caused by the second tunnel are also evaluated.
by Suchatvee Suwansawat.
Sc.D.
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Manyame, Comfort. "On farm yield and water use response of pearl millet to different management practices in Niger." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1203.
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Brett, Aidan. "SEEKING A BALANCE: THE IMPACT OF FOSTERING AUTHORIAL EMPATHY ON TEACHERS AND STUDENTS." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/509326.
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Literacy & LearnersPh.D.
This study reports on the impact of the Authorial Empathy Scale (AES), a tool designed to measure responses to literature that balance attention both to authors’ aesthetic choices and to empathetic engagement with the narrative world, on teachers’ instructional practices and students’ written and spoken responses. The research is guided by the following research questions: (1) In what ways, if any, does a literary unit intervention designed to foster readings of authorial empathy shape the teaching practice of two secondary ELA teachers? (2) In what ways, if any, does a literary unit intervention designed to foster readings of authorial empathy shape secondary students’ responses to texts? Data consist of stimulated-recall interviews and discussion transcripts of teachers and students that were analyzed for the goals, tools, and sources of their decisions. The major findings are the use of the AES seemed to facilitate a common approach among teachers and students for generating more balanced responses to texts. However, sustaining the balanced responses faced challenges in the form of institutional rubrics, IRE discussion patterns, and the specific demands of writing tasks. Students who evidenced greater mastery of the conventions of academic writing tended to generate more authorially empathetic responses to texts. During the Authorial Empathy unit, students tended to engage in more extensive and collaborative talk turns during discussion. The results make clear the importance for teachers to select texts, tasks, and tools that support the use of the AES in guiding students to respond with authorial empathy.
Temple University--Theses
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Ali, Qasim. "Contribution to the mathematical modeling of immune response." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2013. http://tel.archives-ouvertes.fr/tel-00905603.
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The early steps of activation are crucial in deciding the fate of T-cells leading to the proliferation. These steps strongly depend on the initial conditions, especially the avidity of the T-cell receptor for the specific ligand and the concentration of this ligand. The recognition induces a rapid decrease of membrane TCR-CD3 complexes inside the T-cell, then the up-regulation of CD25 and then CD25-IL2 binding which down-regulates into the T-cell. This process can be monitored by flow cytometry technique. We propose several models based on the level of complexity by using population balance modeling technique to study the dynamics of T-cells population density during the activation process. These models provide us a relation between the population of T-cells with their intracellular and extracellular components. Moreover, the hypotheses are proposed for the activation process of daughter T-cells after proliferation. The corresponding population balance equations (PBEs) include reaction term (i.e. assimilated as growth term) and activation term (i.e. assimilated as nucleation term). Further the PBEs are solved by newly developed method that is validated against analytical method wherever possible and various approximate techniques available in the literature.
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Lim, Shannon B. "Modulation of stochastic vestibular stimulation-induced reflexes within a dynamic balance paradigm : the effect of response phase and emotional state." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50260.
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The vestibular system is a complex network that plays an important role in balance control. When postural perturbations are exerted on the individual, it appears that the vestibular system plays a role in modulating the amplitude of the responses. The vestibular system is also susceptible to changes in psychosocial and autonomic states. Despite these findings, the inability to precisely record from and directly manipulate the system has hindered the field in completely understanding how the vestibular system is involved in balance. Therefore, the purposes of this thesis were 1) to investigate if there was phase-dependent modulation of the vestibular reflex during the postural responses and 2) to determine if the vestibular reflex was altered with postural threat.
Stochastic vestibular stimulation (SVS) was used to electrically probe the vestibular system while participants stood on a rotating platform. The vestibular reflex was analyzed by estimating the vestibulo-muscular (SVS-EMG) relationship using time-dependent SVS-EMG coherence throughout the postural response for the first purpose while, for the second purpose, SVS-EMG coherence, cumulant density, and gain were calculated between non-threatening and threatening conditions. Results from this thesis were unable to determine if there were phase-dependent modulations of the SVS-induced vestibular reflex. However, further testing and pilot data provides a promising method for further investigation. Furthermore, an increase gain in and coupling of the vestibular reflex was observed in the most muscles while a decrease in coupling was observed for the paraspinal muscles in the threatening situation. These results suggest that the central nervous system has the ability to prepare the body for responding to an upcoming postural perturbation by optimizing the vestibular output to the muscles.Education, Faculty of
Kinesiology, School of
Graduate
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Barbour, George W. "The growth response of the broiler chick to changes in the protein source and amino acid balance of the diet /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487599963593176.
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Gildenhuys, Fourie. "An improved device to measure human response to dorsiflexion and plantar flexion perturbations." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/96000.
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Thesis (MEng) -- Stellenbosch University, 2014.ENGLISH ABSTRACT: The Dorsiflexometer is a device designed and built for the assessment of a patient’s balance capabilities. The birth of the Dorsiflexometer is due to a serious need for physiological balance assessment equipment, capable of conducting dynamic tests in the clinical setting. This is accomplished by recording and analysing the patient’s response to sagittal plane perturbations. The Dorsiflexometer is operated from a computer software interface program. It uses the measurements from a single force plate to calculate four balance metrics’ characterising a patient’s ability to maintain balance. These balance metrics include the sway index, equilibrium score, postural stability index and radius parameter. A single and a double inverted pendulum model of the human body is derived to calculate a patient’s centre of mass movement in the sagittal plane with the measured force plate data and body parameters. Three experiments, involving 48 subjects, were conducted. The experimental tests proved the competency of the machine, the accuracy of both inverted pendulum models and the balance response of seafarers aboard an Antarctic research and supply vessel during rough sea conditions. The tests concluded that the inverted pendulum models can be used to calculate the body centre of mass displacement. The double inverted pendulum model results are more accurate compared with the single inverted pendulum model. During rough sea conditions, the body movement and postural response of seafarers are increased in order to keep themselves upright. The body is furthermore exposed to a fluctuating ground reaction force which may lead to the progression of osteoarthritis and musculoskeletal injuries. The Dorsiflexometer proved to be capable of conducting repeatable assessments and yielding accurate results which can be used to distinguish between balance capabilities.
AFRIKKANSE OPSOMMING: Die Dorsiflexometer is ’n apparaat wat die balansvermoë van pasiënte analiseer. Die masjien is ontwerp en vervaardig weens die groot behoefte aan fisiologiese balans assesserings toerusting wat dinamiese toetse in die mediese sektor kan bepaal. Dit word bereik deur pasiënte se liggaamsreaksie in die sagittale vlak te meet en te assesseer. Die Dorsiflexometer is beheerbaar vanaf ’n rekenaar sagteware koppelvlak program. Die masjien maak gebruik van ’n enkele kragplaat om pasiënte se balans statistieke te meet. Hierdie balans statistieke wat die pasiënte se balans vermoë beskryf en karakteriseer behels die sogenaamde: swaai indeks, balans telling, posturale stabiliteit indeks en die radius parameter. ’n Enkel en dubbel inverse slinger model van die liggaam is afgelei. Hierdie modelle maak gebruik van ’n pasiënt se kragplaat metings en sy liggaamlike parameters om die swaartepunt tydens beweging te bereken. Drie eksperimente, waarin 48 persone betrokke was, is gedoen. Die eksperimente is gedoen om die apparaat se bevoegdheid te bewys, die akkuraatheid van altwee inverse slinger modelle te toets en verder die balans van seevaarders op die Antarktiese navorsings en toevoer skip tydens rowwe see toestande te analiseer. Die toetse het bewys dat die inverse modelle gebruik kan word om die liggaam se swaartepunt te bereken. Die dubbel inverse slinger model resultate is wel akkurater as die enkel slinger model. Daar is bevind dat seevaarders van meer liggaamsbeweging en posturale reaksies gebruik moet maak om orent te bly tydens rowwe seetoestande. Verder word hul liggame blootgestel aan ’n wisselende grond reaksie krag wat kan lei tot die ontwikkeling van osteoarthritis en muskuloskeletale beserings. Die Dorsiflexometer is bewys as ’n aparaat wat wat akurate resultate lewer vir herhaalbare assesserings. Dit kan gebruik word om te onderskei tussen verskillende balans vermoëns.
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Nabavi, Seyed Ghavamoddin. "Statistical Analysis of Steady State Response in RF Circuits via Decoupled Generalized Polynomial Chaos." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35293.
Full textAbstract:
One of the major factors in RF circuit design is the ability to predict the performance of these circuits in the presence of uncertainty in the key design parameters. This is referred to as uncertainty quantification in the mathematical literature. Uncertainty about the key design parameters arises mainly from the difficulty of controlling the physical or geometrical features of the underlying design, especially at the nanometer level. With the constant trend to scale down the process feature size, uncertainty quantification becomes crucial in shortening the design time.
This thesis presents a new approach to statistically characterize the
variability of the Harmonic Balance analysis and its application to Intermodulation distortion analysis in the presence of uncertainty in the design parameters. The new approach is based on the concept of Polynomial Chaos (PC) and Stochastic Galerkin (SG) methods. However, unlike the traditional PC, the proposed approach adopts a new mathematical formulation that decouples the Polynomial Chaos problem into several problems whose sizes are equal to the size of the original Harmonic Balance problem. The proposed algorithm produces significant CPU savings with equivalent accuracy to traditional Monte Carlo and standard PC approaches.
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Weidemann, Stephanie Suzanne. "Glacier response to climate variability and climate change across the Southern Andes." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22954.
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Die Gletscherschmelze in den südlichen Anden trägt maßgeblich zum Anstieg des Meeresspiegels der letzten Jahrzehnte bei und beeinflusst regional die saisonale Wasserverfügbarkeit. In jüngster Zeit wurde eine rapide Zunahme der Massenverluste insbesondere einzelner großer Auslassgletscher des Südlichen Patagonisches Eisfeldes beobachtet. Im Rahmen der Dissertation wurden die rezente Variabilität des Klimas und der klimatischen Massenbilanz für ausgewählte vergletscherte Gebiete in Patagonien und Feuerland untersucht. Die Verbesserung unseres Verständnisses über räumliche und zeitliche Muster der klimatischen Massenbilanz, ihrer atmosphärischen Antriebsfaktoren und ihres Einflusses auf das in jüngster Vergangenheit beobachtete individuelle Gletscherverhalten, sind weitere wichtige Ziele. Da die Klimavariabilität die Hauptursache für lokale Veränderungen in der Kryosphäre der südlichen Anden ist, wurden langjährige meteorologische Beobachtungen im Gebiet der Gran Campo Nevado-Eiskappe im südlichsten Patagonien im Hinblick auf räumliche und zeitliche Variabilität untersucht und der Einfluss mesoskaliger Wettermuster und Modi atmosphärischer Oszillationen auf die Ausprägung des Klimas analysiert. Darüber hinaus wurde die rezente Variabilität der klimatischen Massenbilanz für ausgewählte Gletscher in Südpatagonien und Feuerland durch die Implementierung des Energie- und Massenbilanzmodells COSIMA simuliert. Eine unterschiedliche Ausprägung der Oberflächenmassenbilanz und geodätischer Massenbilanz unterstreicht wie wichtig ein besseres Verständnis über die Prozesse der klimatischen Massenbilanz und Eisdynamik ist. Des Weiteren wurden Simulationen der klimatischen Massenbilanz eingesetzt, um eine ausgeglichene Massenbilanz für rezente und vergangene Ausdehnungen des Gletschers Schiaparelli abzuleiten. Ziel war es, eine modellgestützte Annäherung an die klimatischen Bedingungen während der Kleinen Eiszeit zu simulieren.Glacier mass loss of the Southern Andes contributes largely to sea-level rise during recent decades and also affects the regional water availability. Despite the overall glacier retreat of most glaciers in Patagonia and Tierra del Fuego, a recent increase in mass loss of individual glaciers has been observed. The recent variability of climate and climatic mass balance for selected glaciated study sites in Patagonia and Tierra del Fuego are investigated in this thesis. Improving our understanding on the spatial and temporal variations of climatic mass balance processes, its atmospheric drivers, and their impact on the recently observed individual glacier behavior are further important aims. Since climate variability is the key driver of local changes in the cryosphere in the Southern Andes, a unique record of meteorological observations across the Gran Campo Nevado Ice Cap in Southernmost Patagonia was analyzed with regard to main climate features and the relationship between the in-situ observations, large-scale climate modes and mesoscale weather patterns. Furthermore, recent climatic mass balance variability was simulated for selected glaciers in Southern Patagonia and Tierra del Fuego by implementing the ’COupled Snow and Ice energy and MAss balance model’ COSIMA. Contrasting patterns of positive simulated annual climatic mass balance and clearly negative geodetic mass balance were found for two neighboring glaciers of the Southern Patagonia Icefield between 2000 and 2014. This highlights the importance of understanding of both, the climatic mass balance, and the ice-dynamical processes. Climatic mass balance simulations were further used to derive glacier steady-state conditions for recent and past glacier extents of Schiaparelli Glacier, aiming for a model-based approximation of climate conditions during the Little Ice Age.
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Eckstrand, Marlene. "Trunk balance in stroke, the effects of right and left cerebral lesions on the sensory and motor components of response to tilt." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq26319.pdf.
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Guggisberg, Alarcón Gabriel Ignacio. "Perfeccionamiento del equipo Thermal Response Test y estudios de rendimientos térmicos para el diseño de un sistema geotérmico de baja entalpía en sistemas de entibación." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/112038.
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Ingeniero CivilActualmente la geotermia ha comenzado su explotación con la finalidad de generación eléctrica mediante una producción limpia con bajos niveles de contaminación en comparación a las generaciones convencionales. Esta línea de estudio apunta a un aprovechamiento de las propiedades térmicas del suelo y no a la generación eléctrica, mediante la obtención de calor o frío que otorgan las propiedades del terreno que a primera vista satisfacen tanto las necesidades de verano como las de invierno, pues el suelo mantiene una temperatura constante entre los 5 y 30 metros de profundidad, temperatura que mediante nuevas tecnologías puede ser absorbida, en este caso con agua, y transportada para abastecer sistemas de climatización como sistemas de agua caliente sanitaria. En la primera etapa de estudio de la utilización de geotermia de baja entalpía enfocada a la edificación (Muñoz, 2011) se implementaron dos Pilas de entibación y sus correspondientes Anclajes con el objetivo de medir el potencial geotérmico de estos elementos embebidos en el subsuelo. El presente trabajo tiene como objetivo continuar el desarrollo de conocimiento acerca del potencial aprovechamiento geotérmico de estas instalaciones. El trabajo se desarrolló en el periodo de construcción del proyecto Beauchef 851, perteneciente al edificio de la Escuela de Ingeniería de la Universidad de Chile, entre Septiembre del 2011 y Mayo del 2012, abarcando tres líneas principales; estudio y re-diseño del equipo de medición Thermal Response Test (TRT), mediciones en terreno entre Diciembre 2011 y Abril 2012, y finalmente estudio del rendimiento energético de las instalaciones. El equipo TRT mejorado permitió realizar una serie de mediciones exitosas para la obtención de parámetros de diseño de las instalaciones, como conductividad térmica tanto para la Pila como para los Anclajes y el rendimiento energético de estas mismas instalaciones. Las mediciones en terreno fueron variadas, utilizando distintas metodologías según el parámetro o información que se quisiera obtener, en este trabajo se definieron mediciones para conocer la influencia de la exposición a condiciones ambientales de las instalaciones, mediciones para conocer la temperatura inalterada tanto de la Pila como de los Anclajes, y finalmente mediciones para la obtención de la conductividad térmica de las instalaciones. Mediante las mediciones realizadas se caracterizó la temperatura interna de las instalaciones, obteniendo perfiles de variación diaria de acuerdo a la temperatura ambiental, durante el periodo en que la Pila se encontraba expuesta a condiciones ambientales (parcialmente) en un 46%. Con todas las mediciones analizadas se definió la conductividad térmica de una Pila con el valor de 1,6 W/mK y un valor de 1,7 W/mK para los Anclajes. Con esto se obtuvo finalmente el rendimiento de un sistema geotérmico implementado en el interior de estructuras de sostenimiento, alcanzado valores de 150 W/mK en el caso de las Pilas y 100 W/mK en el caso de los Anclajes como tasas de rechazo de calor para la carga térmica aplicada de 4500 W en promedio.
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Ennaji, Hasna Sara. "The effect of external perturbations on the reactive balance response of young and older women in a simulated real-world context: public transportation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Find full textAbstract:
Il progressivo invecchiamento della popolazione sta sempre più sottolineando la necessità di un’accurata comprensione del tema delle cadute. Ancora oggi per gli anziani esse rappresentano una delle maggior cause di comorbidità e morte. Il traporto pubblico è un’importante risorsa di inclusione sociale e autonomia personale per la popolazione anziana, tuttavia esso comporta anche una maggiore esposizione al rischio di caduta. Le donne, notoriamente più esposte al rischio di caduta rispetto la controparte maschile, risultano maggiormente colpite da questi incidenti. Il contributo delle nuove tipologie di allenamento “pertubation-based” potrebbero essere una valida soluzione per il miglioramento dei tempi e modalità di risposta del soggetto a perturbazioni esterne che possono comportare una perdita di equilibrio. Il presente studio ha incluso 36 donne suddivise in giovani e anziane con lo scopo di descriverne differenze e caratteristiche nella risposta reattiva quando esposte a perturbazioni esterne, come quelle che possono riscontrarsi sui mezzi pubblici. I risultati hanno evidenziato le potenzialità e i limiti dei protocolli di allenamento che fanno uso di “treadmill perturbativi”, e costituiscono un vero e proprio studio di fattibilità di questi nuovi metodi per la prevenzione delle cadute.
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Iourtchenko, Daniil V. "Optimal bounded control and relevant response analysis for random vibrations." Link to electronic thesis, 2001. http://www.wpi.edu/Pubs/ETD/Available/etd-0525101-111407.
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Thesis (Ph. D.)--Worcester Polytechnic Institute.Keywords: Stochastic optimal control; dynamic programming; Hamilton-Jacobi-Bellman equation; Random vibration. Keywords: Stochastic optimal control; dynamic programming; Hamilton-Jacobi-Bellman equation; Random vibration; energy balance method. Includes bibliographical references (p. 86-89).
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Hale-Ross, S. A. "The UK's legal response to terrorist communication in the 21st century : striking the right balance between individual privacy and collective security in the digital age." Thesis, Liverpool John Moores University, 2017. http://researchonline.ljmu.ac.uk/6726/.
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The dynamics of private life have changed along with the vast advancements in 21st Century communications technology. Private conversations no longer simply take place in the citizens’ home or through using a landline telephone, but rather online through the Internet, social media and through the ever-growing list of chat applications available on the smartphone that allows encryption. However, what often follows the legitimate use of technological advancements is criminal, or in this case terrorist exploitation. In the digital age it has become increasingly easy for terrorist groups to communicate their propaganda and for individual terrorists to communicate freely. This has served to create an investigatory capabilities gap thereby increasing the pressures on UK policing and security agencies’, in fulfilling their task of protecting national security and protecting the citizens’ right to life. In response, the UK and the European Union (EU) have attempted to close the capabilities gap and thereby ensure collective security, by enacting new laws allowing the law enforcement agencies’ to monitor electronic communications. The UK Government has recently enacted the Investigatory Powers Act 2016 (IPA) that introduces and preserves the ability to bulk collect, and retain electronic communications data, and to attain the operators’ assistance in decryption. Although the IPA attempts to take a human rights approach, the main contentious elements in the Act are those in relation to the authorities’ capabilities to intercept electronic communications data on mass, and to retain such data. Specifically, concerns currently surround the introduction of ‘backdoors’ into encrypted online services, and bulk interception and equipment interference warrants, and bulk personal data sets, all of which serve to weaken the security and individual data protection and privacy rights of, potentially, the entire population. The Court of Justice of the European Union (CJEU) has been the most influential judicial body in terms of individual data protection, and thereby on the UK’s law making process, through its key judgements in Digital Rights Ireland Ltd v Minister for Communications, Marine and Natural Resources and others, and the conjoined case of Kärntner Landesregierung, Michael Seitlinger, Christof Tschohl and others (Digital Rights Ireland). The CJEU has done this by asserting the EU’s constitutional and legal prowess in protecting data protection, such as Article 8 of the Charter of Fundamental Rights and byway of two directives, namely the Data Protection Directive in 1995 and the e-Privacy Directive in 2002. In order to close the capabilities gap ensuring national security, the UK Government must ensure the law endures by safeguarding the cohesiveness with the jurisprudence of the CJEU and the European Court of Human Rights (ECtHR). The courts do focus on different elements, built around the Conventional rights, with the CJEU focused on data protection and the ECtHR on Article 8 right to privacy. To solve the balance between individual privacy and collective security, a human rights focus is required with emphasis placed on the practical reality that one cannot assert privacy rights, if one’s right to life is not fully protected in the first place. This focus must re-forge the UK’s counterterrorism legal structure. Taken in conjunction with the UK’s already broadly worded counterterrorism legal framework, particularly the lack of a freedom fighter exclusion within the legal definition of terrorism, the consequence is to almost criminalise any expression of a view that the armed resistance to a brutal or repressive anti-democratic regime, could in certain circumstances be justifiable, even where such resistance is directed away from non-combatant casualties’. Although the current counterterrorism structure is broad, the UK and the EU must police the Internet and remove the safe places used by criminals and terrorists. The IPA fashions a way within which to achieve this, but because it can be aimed at the whole population, subject to authorisation safeguards, and following historical case law dealing with blanket policies that effect the innocent, it is likely to receive continual CJEU and ECtHR judicial scrutiny. Post the UK’s exit from the EU however, the CJEU may become less important leaving the ECtHR to conduct the analysis. At present, the UK must follow CJEU rulings when the matter concerns EU law, whereas ECtHR decisions are merely recommendatory. The thesis found that overall, the balance between collective security and individual data privacy rights in the UK are fairly stable because of the role and importance of judicial review; judicial independence, and the over-arching scrutiny provided by commissioners and parliamentary committees. It is further argued that a blanket approach to retaining electronic communications data is necessary in finding the terrorist in the ever growing haystacks, because sometimes privacy rights and data protection must be curtailed to ensure the state can protect citizens’ rights to life.
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Perin, Pedro Claudinei. "Metodologia de padronização de uma célula de fabricação e de montagem, integrando ferramentas de produção enxuta." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18140/tde-27072017-143408/.
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Este trabalho propõe criar uma metodologia para a padronização de atividades de células de manufatura e de montagem. A metodologia compreende a seleção de algumas ferramentas de produção enxuta e de uma aplicação das mesmas. O desenvolvimento da metodologia ocorre em conjunto com a aplicação, caracterizando desta forma uma pesquisa-ação, uma vez que conceitos e ferramentas são revisados e adequados durante as aplicações. A metodologia é baseada no evento kaizen e sua aplicação tem duração de dois meses. O evento kaizen é utilizado na primeira semana e as demais semanas são dedicadas para acompanhamento das ações de melhorias. As duas últimas semanas são dedicadas à avaliação de resultados. Publicações na literatura científica relacionadas à padronização são poucas, por esta razão pode-se afirmar que este trabalho tem uma contribuição academicamente relevante com o tema e que empresas podem conhecer os requisitos básicos para aplicação da metodologia, podendo explorar seus benefícios. Um dos passos importante da metodologia é a definição das melhores práticas. A participação dos operadores na validação da distribuição das atividades para cada operador e na definição do ritmo de produção é um dos requisitos para o sucesso da implementação. Um processo padronizado permite distinguir uma situação normal de uma anormal. Desta forma ações corretivas podem ser definidas e implementadas. Esta metodologia apresenta um método simples para definição da capacidade instalada e de utilização de operador e máquina de uma célula de manufatura. A aplicação acontece em uma empresa de autopeça. Durante a aplicação, conceitos de manufatura enxuta são disseminados e as pessoas são instigadas a encontrar os desperdícios dentro do processo a ser padronizado. Esta metodologia é resultado de mais de quatorze aplicações e uma delas é utilizada neste trabalho para descrever a metodologia de padronização.This research proposes to build a methodology for standardization activities of a manufacturing process. The methodology consists of a selection of tools from lean manufacturing systems and of application method. The development of this methodology occurred in parallel with his application, when conceptions and tools are revised and adapted. The standardization methodology is based on kaizen event and whole application takes two months. The kaizen event is used at the first week, when the bets practice are defined and implemented. The rest of the schedule is used for follow up and improvement action implementation. The two last week are dedicated for results analyzes. At science literature, publications about manufacturing activities standardization are not much available. Considered that, it might affirm this research has academic contributions for the theme and organization can find some basic requirement for standardization work application. One of the important phases of the methodology is to define the best practice. The labor participation is one of the requirements for implementation successes. Their participation at the validation of task operator distribution and cycle time definition, ensure the maintenance of standardized work. A standardize process enable distinguish one normal condition of abnormal one. Then corrective action can be defined and implemented. This methodology presents a simple method to define the real install capacity andthe labor and machine utilization of the manufacturing cells. The application occurs at assembly supplier company. During the application, lean manufacturing concepts are disseminated and the people are instigated to find the waste into the process. This methodology is result of more than fourteen applications and one of then is used in this dissertation to describe the methodology.
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Kim, Tae-Chung. "Analysis of Clearance Non-linearities and Vibro-impacts in Torsional Systems." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1053634349.
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Laubscher, Sydney. "MANGANESE UPTAKE IN RED MAPLE TREES IN RESPONSE TO MINERAL DISSOLUTION RATES IN SOIL." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1574431912056187.
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Werncke, Daíse. "Relação entre restrição nutricional e acidose ruminal com as alterações na produção e composição do leite." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/163326.
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O estudo consistiu de dois experimentos com o objetivo de avaliar os efeitos da acidose ruminal e restrição nutricional na ocorrência de processos inflamatórios nos animais e relacionar com as alterações na produção e composição do leite. Foram utilizadas doze vacas Holandês e Mestiças Holandês Jersey. Experimento 1: Na fase de adaptação, os animais receberam uma dieta formulada para atender 100% das necessidades nutricionais de energia e proteína. Na indução foi administrada uma dieta com restrição de 50% das necessidades em energia e proteína. Na recuperação os animais receberam uma das três dietas experimentais, para recuperar a estabilidade do leite: (1) suprimento somente de energia; (2) suprimento somente de proteína; (3) suprimento de energia e proteína. A restrição nutricional em energia e/ou proteína afeta negativamente a produção de leite, o peso vivo e o escore de condição corporal. Além de reduzir a eficiência de utilização de proteína da dieta e provocar uma maior instabilidade do leite ao teste do álcool. Entretanto, não altera o perfil sanguíneo e metabólico. Experimento 2: Os animais foram divididos em dois grupos (1) controle e (2) acidose. O delineamento experimental foi reversível simples com dois tratamentos e dois períodos experimentais. Foram analisados parâmetros referente às características físico-quimica, saúde da glândula mamária, medidas fisiológica, perfil metabólico e parâmetros sanguíneos. A indução da acidose ruminal subaguda (SARA) causou redução da produção e estabilidade do leite ao teste do álcool, pH urinário, pH fecal, pH ruminal. Entretanto, a indução a SARA não alterou os parâmetros sanguíneos avaliados. A SARA altera as características físico-químicas do leite, sem influenciar nas concentrações proteínas de fase aguda, caracterizando uma resposta inflamatória. A SARA pode acometer os animais sem apresentar mudanças no perfil sanguíneo dos mesmos.The study consisted of two experiments with the aim of evaluating the effects of ruminal acidosis and nutritional restriction on the occurrence of inflammatory processes in animals and correlate with changes in milk production and composition. Twelve Holstein and cross bred Holstein and Jersey cows were used. In the first study, in the adaptation phase, the animals received a diet formulated to supply 100% of the nutritional needs of energy and protein. In the induction, a diet composed by 50% restriction of energy and protein requirements was administered. In the recuperation, the animals received one of the three experimental diets to recover milk stability: (1) only energy supply; (2) supply only of protein; (3) supply of energy and protein. The nutritional restriction in energy and / or protein can affects negatively milk production, weight and condition score body. In addition to reduce the efficiency of protein utilization of the diet and cause greater instability of the milk to the alcohol test. However, it does not changed the blood and metabolic profile. In second study, the animals were divided into two groups (1) control and (2) acidosis. The experimental design was simple reversible with two treatments and two experimental periods. Physiochemical characteristics, health of the mammary gland, physiological measures, metabolic profile and blood parameters were analyzed. Losses in milk production, reduction of alcohol stability test, urinary pH, fecal pH, ruminal pH were caused by Subacute ruminal acidosis (SARA) induction. However, induction of SARA did not changed the blood parameters evaluated. SARA changes the physical-chemical characteristics of the milk, without influencing the acute phase proteins concentrations, characterizing an inflammatory response. SARA can affect the animals without demostrate changes in the blood profile of the animals.
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Máša, Vítězslav. "Matematický model kotle na biomasu pro účely řízení." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-233909.
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he thesis focuses on building of dynamic mathematical model of biomass boiler as a controlled system and the use of this model in practise. At the first part of the thesis the area of energy production using biomass is introduced and the current development at the area of the automatic control of biomass boilers with medium energy output (in units of MW) is described. Although the main topic of the thesis is the construction of model of biomass boiler for control purposes, thesis deals with technology of boilers and principles of its inner processes as well. Creation of the model comes out not only from these important findings, but also from experimental data collected during measurements in real operation. Heat and mass balance calculations were made according to these data and they serve to precise static properties of experimental unit for biomass combustion. Central part of the thesis presents development of the final model that resulted from balance calculations and from step responses of the system obtained by measuring. Built dynamic model is compared with experimental data through simulations in Simulink and verified. At the next part the model of controlled system is completed with control system and closed-loop control circuit is validated and verified by simulation. Then the design of new controller configuration, which improves the quality of control considerably, is presented. At the final part of the thesis, possibilities of other use of the model of boiler are given, both in control theory and in industrial practice.
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Anil, Kumar K. R. "Computational Studies On Certain Problems Of Combustion Instability In Solid Propellants." Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/244.
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This thesis presents the results and analyses of computational studies on certain problems of combustion instability in solid propellants. Specifically, effects of relaxing certain assumptions made in previous models of unsteady burning of solid propellants are investigated. Knowledge of unsteady burning of solid propellants is essential in studying the phenomenon of combustion instability in solid propellant rocket motors.
In Chapter 1, an introduction to different types of unsteady combustion investigated in this thesis, such as 1) intrinsic instability, 2) pressure-driven dynamic burning, 3) extinction by depressurization, and 4) L* -instability, is given. Also, a review of previous experimental and theoretical studies of these phenomena is presented. From this review it is concluded that all the previous studies, which investigated the unsteady combustion of solid propellants, made one or more of the following assumptions: 1) quasi-steady gas-phase (QSG), 2) quasi-steady condensed phase reaction zone (QSC), 3) small perturbations, and 4) unity Lewis number. These assumptions limit the validity of the results obtained with such models to: 1) relatively low frequencies (< 1 kHz) of pressure oscillations and 2) small deviations in pressure from its steady state or mean values. The objectives of the present thesis are formulated based on the above conclusions. These are: 1) to develop a nonlinear numerical model of unsteady solid propellant combustion, 2) to relax the assumptions of QSG and QSC, 3) to study the consequent effects on the intrinsic instability and pressure-driven dynamic burning, and 4) to investigate the L* -instability in solid propellant rocket motors.
In Chapter 2, a nonlinear numerical model, which relaxes the QSG and QSC assumptions, is set up. The transformation and nondimensionalization of the governing equations are presented. The numerical technique based on the method of operator-splitting, used to solve the governing equations is described.
In Chapter 3, the effect of relaxing the QSG assumption on the intrinsic instability is investigated. The stable and unstable solutions are obtained for parameters corresponding to a typical composite propellant. The stability boundary, in terms of the nondimensional parameters identified by Denison and Baum (1961), is predicted using the present model. This is compared with the stability boundary obtained by previous linear stability theories, based on activation energy asymptotics in the gas-phase, which employed QSC and/or QSG assumptions. It is found that in the limit of large activation energy and low frequencies, present result approaches the previous theoretical results. This serves as a validation of the present method of solution. It is confirmed that relaxing the QSG assumption widens the stable region. However, it is found that a distributed reaction in the gas-phase destabilizes the burning. The effect of non-unity Lewis number on the stability boundary is also investigated. It is found that at parametric values corresponding to low pressures and large flame stand-off distances, small amplitude, high frequency (at frequencies near the characteristic frequency of the gas-phase) oscillations in burning rate appear when the Lewis number is greater than one.
In Chapter 4, the effect of relaxing the QSG assumption is further investigated with respect to the pressure-driven dynamic burning. Comparison of the pressure-driven frequency response function, Rp, obtained with the present model, both in the QSG and non-QSG framework, with those obtained with previous linear stability theories invoking QSG and QSC assumptions are made. As the frequency of pressure oscillations approaches zero, |RP| predicted using present models approached the value obtained by previous theoretical studies. Also, it is confirmed that the effect of relaxing QSG is to decrease the |Rp| at frequencies near the first resonant frequency. Moreover, relaxing QSG assumption produces a second resonant peak in |Rp| at a frequency near the characteristic frequency of the gas-phase. Further, Rp calculated using the present model is compared with that obtained by a previous linear theory which relaxed the QSG assumption. The two models predicted the same resonant frequencies in the limit of small amplitudes of pressure oscillations. Finally, it is found that the effect of large amplitude of pressure oscillations is to introduce higher harmonics in the burning rate and to reduce the mean burning rate.
In Chapter 5, first the present non-QSC model is validated by comparing its results with that of a previous non-QSC model for radiation-driven burning. The model is further validated for steady burning results by comparing with experimental data for a double base propellant (DBP). Then, the effect of relaxing the QSC assumption on steady state solution is investigated. It is found that, even in the presence of a strong gas-phase heat feedback, QSC assumption is valid for moderately large values of condensed phase Zel'dovich number, as far as steady state solution is concerned. However, for pressure-driven dynamic burning, relaxing the QSC assumption is found to increase |RP| at all frequencies. The error due to QSC assumption is found to become significant, either when |Rp| is large or as the driving frequency approaches the characteristic frequency of the condensed phase reaction zone. The predicted real part of the response function is quantitatively compared with experimental data for DBP. The comparison seems to be better with a value of condensed phase activation energy higher than that suggested by Zenin (1992).
In Chapter 6, burning rate transients for a DBP during exponential depressurization are computed using non-QSG and non-QSC models. Salient features of extinction and combustion recovery are predicted. The predicted critical initial depressurization rate, (dp/dt)i, is found to decrease markedly when the QSC assumption is relaxed. The effect of initial pressure level on critical (dp/dt)i is studied. It is found that the critical (dp/dt)i decreases with the initial pressure. Also, the overshoot of burning rate during combustion recovery is found to be relatively large with low initial pressures. However as the initial pressure approached the final pressure, the reduction in initial pressure causes a large increase in the critical (dp/dt)i. No extinction is found to occur when the initial pressure is very close to the final pressure.
In Chapter 7, a numerical model is developed to simulate the L* -instability in solid propellant motors. This model includes a) the propellant burning model that takes into account nonlinear pressure oscillations and that takes into account an unsteady gas- and condensed phase, and b) a combustor model that allows pressure and temperature oscillations of finite amplitude. Various regimes of L* -burning of a motor, with a typical composite propellant, namely 1) steady burning, 2) oscillatory burning leading to steady state, 3) oscillatory burning leading to extinction, 4) reignition and 5) chuffing are predicted. The predicted dependence of frequency of L* -oscillations on mean pressure is compared with one set of available experimental data. It is found that proper modeling of the radiation heat flux from the chamber walls to the burning surface may be important to predict the re-ignition.
In Chapter 8, the main conclusions of the present study are summarized. Certain suggestions for possible future studies to enhance the understanding of dynamic combustion of solid propellants are also given.
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Ollion, Emilie. "Evaluation de la robustesse des vaches laitières : entre aptitudes biologiques des animaux et stratégies de conduite des éleveurs." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22622/document.
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Les systèmes d’élevage répondant aux principes de l’agroécologie doivent pouvoir s’adapter aux variations de leur environnement, en particulier parce qu’ils sont pensés pour maximiser l’utilisation des ressources locales et minimiser l’utilisation d’intrants. La composante animale des systèmes d’élevage peut dans ce contexte représenter un levier d’adaptation aux perturbations de l’environnement et contribuer à la pérennité des systèmes. Ainsi, produire des connaissances qui permettront de sélectionner des animaux robustes c’est-à-dire capables de se maintenir et de maintenir leurs performances dans un environnement changeant est actuellement un objectif prioritaire de la recherche en zootechnie. Peu de méthodes d’évaluation scientifique de la robustesse des animaux d’élevage ont été développées, et la seule méthode opérationnelle à ce jour, basée sur l’étude statique d’une seule fonction (l’approche norme de réaction) est remise en question. L’objectif de cette thèse est de proposer un cadre d’évaluation opérationnel de la robustesse, c’est-à-dire utilisable en élevage. Dans ce but, nous nous sommes focalisés sur le modèle vache laitière et avons mené deux démarches complémentaires, l’une basée sur l’analyse de données issues de fermes expérimentales de l’INRA et visant à évaluer les aptitudes biologiques des vaches à gérer les compromis (trade-offs) entre fonctions biologiques (lactation, reproduction et survie) en environnement stable puis perturbé. La seconde démarche est basée sur des enquêtes auprès d’éleveurs laitiers en vue de caractériser les stratégies de conduite (objectifs et seuils de performances) qui relèvent de la recherche d’adéquation animal-système et contribue à la robustesse des animaux. Enfin un travail de synthèse a permis d’intégrer les contributions respectives des deux approches dans la conception du cadre d’évaluation de la robustesse, ceci afin qu’il puisse être manipulable par l’ensemble des acteurs de la recherche, du terrain et du développement. Ce cadre opérationnel propose que la robustesse des vaches laitières soit évaluée en confrontant les aptitudes biologiques des animaux exprimées dans un environnement donné, aux stratégies de conduite des éleveurs. Pour ce faire, il convient 1/ de caractériser les trajectoires productives des vaches laitières sur la base de l’expression des compromis entre fonctions biologiques en situation stable et perturbée, 2/ de les confronter aux objectifs et les seuils de performances des éleveurs, 3/ d’analyser l’adéquation entre les profils de performances exprimés par l’animal et les profils de priorisation des performances des éleveurs, 4/ de prendre en compte les complémentarités entre animaux pour passer au niveau troupeau. Des indicateurs de fitness des animaux (longévité, nombre de descendants dans le troupeau) permettent de valider cette analyseAgroecological livestock farming systems have to be able to adapt to environmental variability because they are designed to maximize the use of local resources and minimize the use of inputs. The animal component of livestock farming systems could represent a lever to adapt to environmental disturbances and contribute to systems durability. Thus, producing scientific knowledge allowing the selection of robust animals, able to maintain and maintain their performances in a fluctuating environment is one main stake for farming system research. Few methods have been developed to assess robustness in farm animals, and the only operational measurement (reaction norm) that relies only on the analysis of one function at a given time is currently turned into question. This thesis objective is to propose an operational assessment framework of robustness, that is to say, usable on the field. To that end, we focused on the dairy cow model and carried two complementary approaches, one based on the analysis of data collected from INRA experimental units, aiming at assessing biological aptitudes of dairy cows to manage trade-offs between function (lactation, reproduction and survival) in stable and disturbed environments. The second approach is based on data collected during interviews with dairy farmers in order to characterize their management strategies (objectives and performance thresholds) associated with the search of the animal-system balance contributing to animals’ robustness. Finally, a synthesis integrated the respective inputs of the two approaches in the assessment framework of robustness, in order to make it usable by actors from research, farms and development. This operational framework suggests that robustness of dairy cows should be assessed by comparing biological aptitudes of the animals expressed in a given environment, with the management strategies of farmers. It requires, 1/ to characterized productive trajectories of dairy cows including trade-offs between function in stable and disturbed environment, 2/ to compare them with performance objective and thresholds of farmers, 3/ to analyze the balance between the performances profiles expressed by the animal and the profiles of performances prioritization of farmers, 4/ account for complementarities between animals to step up to the herd level. Animals’ fitness indicators (longevity, number of descendants) are used to validate the analysis
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Karlén, Albin, and Sebastian Genas. "Marginaler för morgondagen : En kvantitativ analys av flexibiliteten hos aggregerade laddande elbilar." Thesis, Linköpings universitet, Energisystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177967.
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Elektrifieringen av bilflottan sker i rasande takt. Även andra samhällssektorers efterfrågan på el väntas öka drastiskt under kommande decennier, vilket i kombination med en växande andel intermittenta energikällor trappar upp påfrestningarna på elnätet och ställer krav på anpassningar. En föreslagen dellösning till kraftsystemets kommande utmaningar är att utnyttja efterfrågeflexibiliteten i laddande elbilar genom att en aggregator styr ett stort antal elbilsladdare och säljer den sammanlagda kapaciteten på till exempel Svenska kraftnäts stödtjänstmarknader. För att avgöra hur mycket flexibilitet som elbilsladdning kan bidra med behöver aggregatorn upprätta prognoser över hur mycket effekt som mest sannolikt finns tillgänglig vid en viss tidpunkt – en punktprognos – men också en uppskattning av vilken effektnivå man kan vara nästan säker på att utfallet överstiger – en kvantilprognos. I den här studien har en undersökning gjorts av hur prognosfelet förändras om gruppen av aggregerade elbilsladdare ökas, och hur mycket en aggregator på så sätt kan sänka sina marginaler vid försäljning av efterfrågeflexibiliteten för att med säkerhet kunna uppfylla sitt bud. Det gjordes genom att kvantifiera flexibiliteten för 1 000 destinationsladdare belägna vid huvudsakligen arbetsplatser, och genom att skala upp och ner datamängden genom slumpmässiga urval. För dessa grupper gjordes sedan probabilistiska prognoser av flexibiliteten med en rullande medelvärdes- och en ARIMA-modell. Utifrån prognoserna simulerades slutligen potentiella intäkter om aggregatorn skulle använda den flexibla kapaciteten för uppreglering till stödtjänsten FCR-D upp, vilket är en frekvensreserv som aktiveras vid störningar av nätfrekvensen. Resultaten visar att en tiodubbling av antalet aggregerade elbilsladdare mer än halverar det relativa prognosfelet. De båda prognosmodellerna visade sig ha jämförbar precision, vilket talar för att använda sig av den rullande medelvärdesmetoden på grund av dess lägre komplexitet. Den ökade säkerheten i prognosen resulterade dessutom i högre intäkter per laddare. De genomsnittliga intäkterna av att leverera flexibilitet från 1 000 aggregerade elbilsladdare till FCR-D uppgick till 6 900 kr per månad, eller 0,8 kr per session – siffror som troligen hade varit högre utan coronapandemins ökade hemarbete. En 99-procentig konfidensgrad för kvantilprognosen resulterade i en säkerhetsmarginal med varierande storlek, som i genomsnitt var runt 90 procent för 100 laddpunkter, 60 procent för 1 000 laddpunkter samt 30 procent för 10 000 laddpunkter. Mest flexibilitet fanns tillgänglig under vardagsförmiddagar då ungefär 600 kW fanns tillgängligt som mest för 1 000 laddpunkter. Att döma av tio års nätfrekvensdata är den sammanlagda sannolikheten för att över 50 procent aktivering av FCR-D-budet skulle sammanfalla med att utfallet för den tillgängliga kapaciteten är en-på-hundra-låg i princip obefintlig – en gång på drygt 511 år. Att aggregatorn lägger sina bud utifrån en 99-procentig konfidensgrad kan alltså anses säkert.The electrification of the car fleet is taking place at a frenetic pace. Additionally, demand for electricity from other sectors of the Swedish society is expected to grow considerably in the coming decades, which in combination with an increasing proportion of intermittent energy sources puts increasing pressure on the electrical grid and prompts a need to adapt to these changes. A proposed solution to part of the power system's upcoming challenges is to utilize the flexibility available from charging electric vehicles (EVs) by letting an aggregator control a large number of EV chargers and sell the extra capacity to, for example, Svenska kraftnät's balancing markets. To quantify how much flexibility charging EVs can contribute with, the aggregator needs to make forecasts of how much power that is most likely available at a given time – a point forecast – but also an estimate of what power level the aggregator almost certainly will exceed – a quantile forecast. In this study, an investigation has been made of how the forecast error changes if the amount of aggregated EV chargers is increased, and how much an aggregator can lower their margins when selling the flexibility to be able to deliver according to the bid with certainty. This was done by quantifying the flexibility of 1000 EV chargers located at mainly workplaces, and by scaling up and down the data through random sampling. For these groups, probabilistic forecasts of the flexibility were then made with a moving average forecast as well as an ARIMA model. Based on the forecasts, potential revenues were finally simulated for the case where the aggregator uses the available flexibility for up-regulation to the balancing market FCR-D up, which is a frequency containment reserve that is activated in the event of disturbances. The results show that a tenfold increase in the number of aggregated EV chargers more than halves the forecast error. The two forecast models proved to have comparable precision, which suggests that the moving average forecast is recommended due to its lower complexity compared to the ARIMA model. The increased precision in the forecasts also resulted in higher revenues per charger. The average income from delivering flexibility from 1000 aggregated electric car chargers to FCR-D amounted to SEK 6900 per month, or SEK 0.8 per session – figures that would probably have been higher without the corona pandemic's increased share of work done from home. A 99 percent confidence level for the quantile forecast resulted in a safety margin of varying size, which on average was around 90 percent for 100 chargers, 60 percent for 1000 chargers and 30 percent for 10,000 chargers. Most flexibility was shown to be available on weekday mornings when approximately 600 kW was available at most for 1000 chargers. By examining frequency data for the Nordic power grid from the past ten years, the joint probability that a more than 50 percent activation of the FCR-D bid would coincide with the outcome for the available capacity being one-in-a-hundred-low, was concluded to be nearly non-existent – likely only once in about 511 years. For the aggregator to place bids based on a 99 percent confidence level can thus be considered safe.
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Schmidt, Daniel, Castro Germano Andresa Mara De, and Thomas Lothar Milani. "Aspects of Dynamic Balance Responses: Inter- and Intra-Day Reliability." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-188620.
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The Posturomed device is used as a scientific tool to quantify human dynamic balance ability due to unexpected perturbations, and as a training device. Consequently, the question arises whether such measurements are compromised by learning effects. Therefore, this study aimed to analyze inter- and intra-day reliability of dynamic balance responses using the Posturomed. Thirty healthy young subjects participated (24.3±3.2 years). The Posturomed was equipped with a triggering mechanism to enable unexpected, horizontal platform perturbations. A force platform was used to quantify Center of Pressure (COP) excursions for two time intervals: interval 1 (0–70 ms post perturbation) and interval 2 (71–260 ms post perturbation). Dynamic balance tests were performed in single leg stances in medio-lateral and anterior-posterior perturbation directions. Inter- and intra-day reliability were assessed descriptively using Bland-Altman plots and inferentially using tests for systematic error and intra-class-correlations. With regard to the mean COP excursions for every subject and all intervals, some cases revealed significant differences between measurement sessions, however, none were considered relevant. Furthermore, intra class correlation coefficients reflected high magnitudes, which leads to the assumption of good relative reliability. However, analyzing inter- and intra-day reliability using Bland-Altman plots revealed one exception: intra-day comparisons for the anterior-posterior direction in interval 2, which points towards possible learning effects. In summary, results reflected good overall reliability with the exception of certain intra-day comparisons in the anterior-posterior perturbation direction, which could indicate learning effects in those particular conditions.
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Neto, Rubelmar Maia de Azevedo Cruz. "Taxa de resfriamento na soldagem: um novo entendimento." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-19092018-094750/.
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Desde meados do século XX, métodos analíticos, numéricos e experimentais foram utilizados para quantificar a eficiência térmica na soldagem a arco, isto é, a razão entre a energia do arco elétrico e a energia que é entregue ao material durante a soldagem. Conhecendo-se a eficiência térmica, as dimensões da chapa e as propriedades térmicas do metal de base, torna-se possível prever as taxas e tempos de resfriamento a partir de modelo analíticos. Consequentemente, permitindo a previsão das transformações de fase, garantindo que os valores das propriedades da junta soldada se enquadrem dentro de um intervalo desejado. Os modelos de previsão de taxa de resfriamento derivados a partir dos modelos analíticos de Rosenthal são validos apenas no regime quase estacionário. Todavia, estes modelos costumam ser utilizados com pouco critério, mesmo em situações em que este regime não é alcançado. Portanto, para o desenvolvimento de modelos mais precisos e acurados para previsões das taxas de resfriamento, torna-se necessário entender como os termos do balanço de energia se desenvolvem durante a soldagem, até atingir o regime quase estacionário. Este trabalho tem como objetivo desenvolver um entendimento mais abrangente dos fatores que impactam nos valores de taxas de resfriamento em juntas soldadas. Realizaram-se ensaios de calorimetria com nitrogênio líquido para diferentes tempos de soldagem, como também, foram coletados ciclos térmicos em diferentes posições ao longo do cordão, buscando entender como as variações no balanço de energia, ao longo da soldagem, impactam no material. A partir da Metodologia de Superfície de Resposta, foram obtidos os modelos empíricos da energia entregue ao material e da eficiência térmica do arco. Um novo entendimento acerca do balanço de energia na soldagem foi alcançado, servindo de base para o desenvolvimento e validação de um modelo preditivo de taxa de resfriamento, válido para diferentes condições de fluxo de energia no material.Since the early 20th century, numerical and experimental methods have been used to quantify the thermal arc efficiency in welding, i.e., the ratio between the electric arc energy and the energy delivered to the material during welding. Knowing the thermal arc efficiency, the sample dimensions and the thermal properties of the base metal, it is possible to predict the cooling rates by analytical models. Consequently, allowing the prediction of phase transformations in the material, ensuring that values of welded joint properties are within a desired range. Cooling rate prediction models derived from Rosenthal\'s analytical models are valid only in quasi-stationary state. However, these models are used with little criterion, even in situations where this state is not achieved. Therefore, to development of more accurate and precise models for the prediction of cooling rate it become necessary to understand the evolution of the energy balance during the welding until the quasi-stationary state was reached. This work aims to develop a more comprehensive understanding of the factors that affect the cooling rate in welded joints. Calorimetry tests with liquid nitrogen were carried out for different welding times, and thermal cycles were collected at different positions along the weld bead, to understand how the variations in the energy balance during the welding affect the material. From the Response Surface Methodology, the empirical models of delivered energy and the thermal arc efficiency were obtained. A new understanding about the energy balance in the welding was found, that was used for the development and validation of a predictive model of cooling rate, valid for different condition of energy flow in the material.
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Franke, Manfred. "Translating Electric KHFAC and DC Nerve Block from Research to Application." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1397006454.
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Welch, Torrence David Jesse. "A feedback model for the evaluation of the adaptive changes to temporal muscle activation patterns following postural disturbance." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29674.
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Thesis (Ph.D)--Biomedical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Ting, Lena; Committee Member: Chang, Young-Hui; Committee Member: Nichols, T. Richard; Committee Member: Schumacher, Eric; Committee Member: Thoroughman, Kurt. Part of the SMARTech Electronic Thesis and Dissertation Collection.