Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2007. / Includes bibliographical references.

Thesis (M.A.)--Kent State University, 2009. / Title from PDF t.p. (viewed April 7, 2010). Advisor: Janis Crowther. Keywords: body image; body checking; social comparisons; ecological momentary assessment. Includes bibliographical references (p. 68-77)

Small Unmanned Aerial Vehicles (UAVs) have seen continual growth in both research and commercial applications. Attractive features such as their small size, light weight and low cost are a strong driver of this growth. However, these factors also bring about some drawbacks. The light weight and small size means that small UAVs are far more susceptible to performance degradation from factors such as wind gusts. Due to the generally low cost, available sensors are somewhat limited in both quality and available measurements. For example, it is very unlikely that angle of attack is sensed by a small UAV. These aircraft are usually constructed by the end user, so a tangible amount of variation will exist between different aircraft of the same type. Depending on application, additional variation between flights from factors such as battery placement or additional sensors may exist. This makes the application of optimal model based control methods difficult. Research literature on the topic of small UAV control is very rich in regard to high level control, such as path planning in wind. A common assumption in such literature is the existence of a low level control method which is able to track demanded aircraft attitudes to complete a task. Design of such controllers in the presence of significant wind or modelling errors (factors collectively addressed as lumped disturbances herein) is rarely considered. Disturbance Observer Based Control (DOBC) is a means of improving the robustness of a baseline feedback control scheme in the presence of lumped disturbances. The method allows for the rejection of the influence of unmeasurable disturbances much more quickly than traditional integral control, while also enabling recovery of nominal feedback con- trol performance. The separation principle of DOBC allows for the design of a nominal feedback controller, which does not need to be robust against disturbances. A DOBC augmentation can then be applied to ensure this nominal performance is maintained even in the presence of disturbances. This method offers highly attractive properties for control design, and has seen a large rise in popularity in recent years. Current literature on this subject is very often conducted purely in simulation. Ad- ditionally, very advanced versions of DOBC control are now being researched. To make the method attractive to small UAV operators, it would be beneficial if a simple DOBC design could be used to realise the benefits of this method, as it would be more accessible and applicable by many. This thesis investigates the application of a linear state space disturbance observer to low level flight control of a small UAV, along with developments of the method needed to achieve good performance in flight testing. Had this work been conducted purely in simulation, it is likely many of the difficulties encountered would not have been addressed or discovered. This thesis presents four main contributions. An anti-windup method has been devel- oped which is able to alleviate the effect of control saturation on the disturbance observer dynamics. An observer is designed which explicitly considers actuator dynamics. This development was shown to enable faster observer estimation dynamics, yielding better disturbance rejection performance. During initial flight testing, a significant aeroelastic oscillation mode was discovered. This issue was studied in detail theoretically, with a pro- posed solution developed and applied. The solution was able to fully alleviate the effect in flight. Finally, design and development of an over-actuated DOBC method is presented. A method for design of DOBC for over actuated systems was developed and studied. The majority of results in this thesis are demonstrated with flight test data.

This thessis deals with assessment of the actual state of an herb layer and regeneration in nature preservations Coufavá and Slunná. Both of nature preservations were affected large-scale wind disturbances. The survey was conducted in June and July 2013. There were totally performed 384 phytosocenological releves (162 in nature preserve Coufavá and 222 in nature preserve Slunná). Research was carried out on a regular grid 15 × 15 meters. There were 254 juvenile trees which were founded in nature preserve Coufavá and also 1891 juvenile trees were founded in nature preserve Slunná. In both of preservations browse didn't rise up 10 % from all regeneration. Most abundant tree species in nature preserve Coufavá were Fagus sylvatica. In nature preserve Slunná were most abundant Tilia sp. Strong clonal species dominated in disturbed desktop non-wood undergrowth in both of studied areas. In closed stand dominated typical forest species. Impatiens parviflora has abundant occurrence in both of biotopes. For both nature preserves was estimated future development and propose of solutions. Result of work should serve as a basis for optimizing the management plan for the said reservation.

There is a large natural disturbance in spruce stands at the present moment in many European countries. Therefore understanding of the long-term natural processes and the impact of disturbances on the structure have a key role in the management of spruce forests. For this purpose, we have studied the structure and the historical regime mountains, which is one of the best preserved forest ecosystems in the Europe. Between 2011 and 2013 years we have founded nearly 50 research spots in the four valleys where we collected data on the structure of the forest. For purposes of reconstruction of disturbances history samples from almost 3 500 individuals of Norway spruce (Picea Abies) were taken. Data were analyzed with dendrochronological methods and descriptive statistics. Partial synchronization of disturbances with the valleys and the subsequent rise in the regeneration was detected, which shows the influence of disturbances evoked by wind and then, probably, by the increasing population of bark beetles. We noticed the importance of the disturbances (weak - strong), which directly influences the structure and creates the mosaic diversity of vegetation. The history of the oldest areas goes back for 400 years, and for the youngest - for 100 years. The volume of the deadwood in the valleys was approximately 135 m3. Overall, on the investigated spots 1380 individuals of regeneration with dominating recovery of Norway spruce (Picea Abies) were recorded, with the proportion of 76 %. Our results show that the disturbances are partially synchronized with the landscape level and also on the level of each valley, and have a major impact on the structure and dynamic of the forest. Natural disturbances are the main factor affecting the natural regeneration of spruce forests.

Disturbance due to habitat restoration and urbanization can threaten populations of sensitive wildlife species. I examined 2 aspects of the ecology of Texas horned lizards (Phrynosoma cornutum), a Species of Special Concern in Oklahoma. I studied the effects of native prairie restoration and urban development on a population of P. cornutum on an urban wildlife reserve at Tinker Air Force Base, Oklahoma. I also studied population vital rate variation in 2 populations of P. cornutum using deterministic elasticity and life-stage simulation analyses. My research on the effects of habitat disturbance on urban P. cornutum focused on Wildlife Reserve 3 (WR3) at Tinker Air Force Base, which has a population of P. cornutum that has persisted for many years. I quantified daily movement rates, home-range size, changes in spatial distribution, survival rates, and population size and density over 9 years (2003-2011). Movement rates of P. cornutum were affected by a 3-way interaction of sex, period (reproductive vs. non-reproductive), and study stage (2004-2005, 2007-2008, and 2009-2011). Stages represented variation in the type and level of anthropogenic disturbance on the site. Home-range size did not vary by sex, but was smaller during the non-reproductive period than the reproductive period. Spatial analyses indicated that disturbances due to restoration activities had little effect on the spatial distribution of P. cornutum on WR3. Survival was affected by season (inactive-season survival was higher), stage (declining survival in later stages with more disturbance), an interaction of season and stage, and disturbance (covariate of proportion of an individual's home range in disturbed areas for a given year; small negative effect), with little evidence for variation in survival by sex. Major causes of mortality included depredation and anthropogenic causes. I estimated a population size of 32.9 ± 4.7 (95% CI of 28.1-49.0) individuals (excluding hatchlings) with a corresponding density of 2.68 lizards/ha. Spatial analyses did not support the hypothesis that disturbance associated with restoration activities affected the spatial ecology of P. cornutum on WR3. However, these results were not entirely conclusive, due to the logistical constraints of working on a single site with an uncommon species. Size and density of the P. cornutum population has apparently declined since 2005. This decline is likely a consequence of 2 factors: the 2008 translocation of 17 adult lizards from an area adjacent to WR3 impacted by housing development coupled with a decrease in the annual survival rate of adults over time. I compared the vital rates of the population of P. cornutum on WR3 to a site in south Texas, the Chaparral Wildlife Management Area (CWMA). The Chaparral WMA population had lower adult survival and higher fecundity than WR3. I predicted a trade-off between the effect of adult survival and fecundity on population growth rate (&lambda). I found that recruitment in P. cornutum most affected &lambda at both sites. Stochastic life-stage simulation analysis indicated that hatchling survival most affected &lambda in both populations. There was a trade-off in effect on &lambda between juvenile survival and fecundity between the two sites; fecundity affected &lambda more at the CWMA. Adult survival had minimal effects on &lambda in both populations. My study suggests that managers can address P. cornutum declines in similar ways across the species' range.

In the boreal forest of Alberta, oil exploration has brought roads into previously undisturbed areas. Peatlands cover vast areas of the boreal forest, transmit water across the landscape, provide habitat for wildlife, and store carbon sequestered from the atmosphere. Roads crossing peatlands is inevitable, and little is known about how roads impact plant communities, water chemistry, and water tables. Few studies of large fen complexes have been conducted in the continental boreal forest, nor have many investigated the impact of roads. Understanding the relationships between species, water chemistry, and microtopography provides insight into the nature of continental fens and how they respond to disturbance. I examined plant communities and water chemistry characteristics of an undisturbed fen and compared the data to nearby peatlands that were disturbed by mineral haul roads. This study determined the control study site was an acidic fen with a pH generally less than 4.0 and four community types were recognized. Most of the complex was very wet, open, oligotrophic poor fen, with a treed, oligotrophic, species poor area extending between two water tracks. As the fen narrowed following its drainage, site type changed to mesotrophic poor fen, with mesotrophic rich fen communities in some marginal areas. The water table was very stable. The road sites showed signs of enriched water chemistry and changed plant communities within 50 meters of the road upstream. Downstream plant communities were less effected. Water tables appear to be influenced both upstream and downstream differently.

The current oak-hickory overstory that exists in the productive uplands of Southern Illinois is a result of a disturbance regime that lasted thousands of years. The species mix that is currently regenerating under this overstory is a consequence of the historic disturbance regime being severely altered in the last century. As the importance and value of the oak-hickory forest type is widely recognized, land managers seek effective ways to ensure the perpetuation of an oak-hickory component in future stands. Across its range, forest management activities are being implemented in an effort to promote oak, with mixed results. The current study was conducted in the eastern portion of the Shawnee National Forest on private land, with the exception of some Burn only and control stands which were located on Forest Service land. Treatments for these stands fell within five distinct groups: TSI, Burn, TSI/Burn, TSI/Harvest, TSI/Harvest/Burn, plus a control group. Data was collected on overstory, regeneration, and site characteristics. The change in height and abundance of oak seedlings across treatment groups was analyzed with an ANCOVA test. The competitive position of oak and hickory seedlings relative to all seedlings was analyzed with an ANOVA test. The results revealed that TSI only may actually put oak regeneration at a disadvantage, possibly because it only increases the amount of light enough to promote shade tolerant species. The TSI/Harvest/Burn group showed potential to increase the size and abundance of oak regeneration, suggesting the need for higher disturbance intensity in order to increase oak regeneration. When competitive position of oak and hickory seedlings were analyzed, the burn only group showed the greatest increase over the control group, reinforcing the idea that fire naturally selects for oak. Management activities should focus on using heavy disturbance to establish oak regeneration, then fire to ensure that they are competitive enough to eventually reach the overstory.

Giant cane (Arundinaria gigantea) is a native bamboo that forms large monodominant stands called canebrakes in bottomlands in the southeastern US. Canebrakes are valuable habitat for wildlife and function as riparian buffers to protect soils and water quality. Currently, only 2% of canebrake ecosystems remain. Thus there is interest in establishing new canebrakes as well as maintaining and expanding existing canebrakes. For field restoration, using cane rhizomes to produce transplants is possible but it is unknown when propagules should be collected and grown. For rehabilitation of existing canebrakes, preliminary studies suggest that fertilization and disturbance such as fire can be beneficial but additional broader-ranging studies are warranted. This research reports on three giant cane studies involving producing transplants from rhizomes and involving managing existing canebrakes with disturbance in southern Illinois. The main objectives of study 1 were to ascertain a) if collection season influences the proportion of rhizome propagules that grow at least one culm (culm production success) and the resultant culm growth when transplanted in a greenhouse b) if specific rhizome characteristics influence an individual rhizome’s ability to produce a culm c) if aboveground biomass could be a predictor of the amount of belowground propagules and d) if aboveground biomass, total rhizome length, number of rhizome nodes, or number of rhizome buds could be a predictor of how many culms could be produced when transplanting. Monthly, for a year, sample plots were randomly selected in the SIUC giant cane nursery. In sample plots aboveground culm measurements were collected included live culm density (#/0.25m2), dead culm density (#/0.25m2), height of the tallest culm (cm), diameter of the tallest culm (mm), and total aboveground biomass (g). Each month rhizomes were dug from the sample plots, measured (length (cm), diameter (mm), # nodes, and # live buds), and transplanted into pots and placed in the greenhouse for approximately 94 days. At that time, measurements were taken of the number of live and dead culms produced per pot and the height of the tallest culm (cm). Results indicate that rhizomes collected and transplanted in the greenhouse during winter and spring months (December-May), had significantly greater culm production success and produced significantly taller culms. Also, rhizomes intermediate in length (18-30 cm) that contained 5 to 12 nodes and 4 to 9 live buds tended to have higher than average culm production. Finally, a positive correlation existed between the amount of aboveground biomass and the number of rhizome nodes, the number of live rhizome buds, and the length of rhizomes found in sample plots. Aboveground biomass can predict the amount of belowground rhizome propagules that can be used for canebrake restoration. Study 2 is a two year continuation of work initiated in 2011 and reported on by Margaret Anderson in 2014 on the effects of fire, fertilization, and fire and fertilization combined on the growth and expansion (culm density, height and diameter) of canebrakes within the Cache River Watershed in southern Illinois. Results showed considerable year to year variability among treatments within the canebrake for some growth parameters. However, three years after disturbance, all treatments tended to have similar culm density and growth values and canebrake expansion occurred for all treatments into exterior plots. Fire alone was similar to controls in growth parameters and did not produce any long-term negative effects. Thus, fire can be used as an effective tool to reduce competition from other species, allowing managed canebrakes to persist longer than those that remain undisturbed. Fertilization used alone and in combination with fire, produced slight growth and density increases, but added costs may not warrant its use in canebrake management. Study 3 compared fire and mowing disturbances on the growth and expansion of remnant canebrakes located in southern Illinois. Eleven replications in remnant canebrakes were established throughout the Cache River watershed. Each replication contained a fire only treatment, a mowing only treatment, and a control. Measurements were taken in the dormant season early in 2012 prior to a single mowing and a single fire in March, and after each growing season thru 2014. Measurements including live and dead culm density (#m2), culm height (cm), and culm diameter (0.01 mm), were taken within subplots in the canebrake interior and exterior. Results from this study showed that mowing can be used as an effective alternative to fire for the management of remnant canebrakes through reductions in competition. Neither fire nor mowing produced negative effects of growth within the measured canebrakes or in adjacent areas. Like the previous study, all treatments including the control experienced an outward expansion of cane culms throughout the course of the study. This study shows that both fire and mowing can be used as effective tools to reduce competition within canebrakes to aid in their continued vigor.

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