Representing Patterns of autonomous agent dynamics in multi-robot systems

It is proposed that vocabularies for representing complex systems with interacting agents have a natural lattice hierarchical structure. We investigate this for the example of simulated robot soccer, using data taken from the RoboCup simulation competition. Lattice hierarchies provide symbolic representations for reasoning about systems at appropriate levels. We note the difference between relational constructs being human supplied versus systems that abstract their own constructs autonomously. The lattice hierarchical representation underlies both

Robotics and the meaning of life: a practical guide to things that think

The new Open University course T184 Robotics and the meaning of life: a practical guide to things that think is an introductory course on robotics. It is an undergraduate course taught at a distance over 10 weeks. The course is centred around a web site containing most of the course material, supported by two books: Ruth Aylett Robots: Bringing intelligent machines to life? which is a general survey of the field and Isaac Asimov I, Robot which is used to motivate questions about the relationship between man and machine. On-line conferences provide study support. There is also a strong practical element to the course. This was originally designed around the use of the Lego Mindstorms robotics kit. Besides mechanical components, the kit includes the Lego RCX brick – a programmable microcontroller with memory and interfaces to input and output devices such as touch and light sensors, motors and an IR channel to communicate with a PC. Students can build and program an autonomous wheeled robot to carry out a range of tasks of increasing difficulty. A new programming environment was developed at the Open University specifically to support the needs of adult learners with no prior experience of programming. This provided an opportunity to extend the capabilities of the Mindstorms kit. For example, the robot can now ‘talk’ by sending IR messages back to the PC where they are turned into spoken phrases. This richer environment is highly motivating. The new software can also take on a processing role to escape the limitations of memory and processing power onboard the robot. For example, students develop a two-agent system in which the mobile robot collects data, transmits it back to the PC where it is analysed using a neural network (built and trained by the student) and results are transmitted back to the running robot. Developing new software also provided an opportunity to produce a simulation of the robot and we can now offer students the choice of carrying out the practical activities with the Lego hardware or as a simulation. We will look at the attitudes and experiences of students who have chosen these different learning approaches

An FPGA architecture for the recovery of WPA/WPA2 keys

Wi-Fi protected access (WPA) has provided serious improvements over the now deprecated wired equivalent privacy protocol (WEP). WPA, however, still has some flaws that allow an attacker to obtain the passphrase. One of these flaws is exposed when the access point (AP) is operating in the WPA personal mode. This is the most common mode as it is the quickest and easiest to configure. It requires the attacker to capture the traffic from four-way handshake between the AP and client, and then provide enough compute time to reverse the passphrase. Attackers quickly noticed that by investing the compute time in advance, and storing their work, they could decrease the time-to-crack for an AP. This caused attackers to start compiling large lookup tables based on dictionaries of common passwords and common SSIDs. The attackers are required to compile a separate lookup table for each SSID, making this style of attack most feasible against APs with a common SSID and password. The work in this thesis will focus on creating an FPGA based architecture to accelerate the generation of the lookup table, given a dictionary of possible Pre-shared Keys and an SSID. The application of this work would be most useful for attacking one-off SSID\u27s. This is because most common SSID\u27s already have a generated lookup table that can be downloaded much faster than it could be generated, so this regeneration would be wasteful. The application will also provide a manner to check for a valid Pairwise Master Key during the table generation phase

The Effects of Family Supportive Supervisor Behaviors (FSSB) on Work and Health Related Outcomes

The composition of the workforce has changed dramatically over the past several decades, the number of dual-career couples and working mothers with young children has increased dramatically. Many organizations have responded by implementing work-family benefits to help employees deal with the conflicting demands of work and family. Yet, researchers have found that these benefits may be underutilized by employees (Allen, 2001). One reason these benefits may be underutilized is due to a lack of perceived supervisor support for the use of these benefits (Cook, 2009). This study will examine the processes underlying how family supportive supervisor behaviors influence positive job and health related outcomes, specifically affective commitment, job satisfaction, and subjective well-being. The model tested in this study suggests that family supportive supervisor behaviors will lead to greater work engagement via gain spirals. This enhanced sense of absorption in and vigor towards one\u27s work is expected to be related to lower levels of work-to-family conflict and greater levels of work-to-family enrichment

Obesity, Self-Complexity, and Compartmentalization: On the Implications of Obesity for Self-Concept Organization

The relationship between obesity and structural aspects of the self-concept was examined in adult women. Participants were 119 adult women [age range: 18-73, M=26.9; body mass index (BMI) range: 16.2-54.7, M=27.3] who completed measures of self-esteem, self-complexity, and the spontaneous self-concept. BMI was associated with less complex and more compartmentalized self-knowledge and more frequent mention of weight-stereotypic traits as self-descriptive. The findings are discussed in the context of research on obesity- related stigma

Epidemiological evaluations of magnitude and the temporal distributions of feedlot heart disease and bovine respiratory disease

Doctor of PhilosophyDepartment of Diagnostic Medicine/PathobiologyMajor Professor Not ListedThe objective of this research was to quantify epidemiologic parameters and associations of risk factors of heart disease in feedlot cattle as well as to analyze temporal distributions of first treatment bovine respiratory disease (BRD) in cohorts with high and low morbidity. Three retrospective studies were conducted to evaluate risk and timing of heart disease in feedlot cattle evaluating different sample populations (individual and cohort data). An additional investigation was performed utilizing retrospective data from a different sample population to investigate BRD morbidity magnitude and timing. Individual first treatment records were utilized to determine if cohorts were high (≥ 15% BRD) morbidity or low (<15% BRD) morbidity, then data were analyzed by clustering on the cumulative distribution of timing of first BRD treatments. A risk association analysis was performed on cohort demographics and risk factors for respective clustering groups. Feedlots utilized multiple diagnoses for heart disease, and multiple case definitions of heart disease increase the risk of potential misclassification. Deaths due to heart disease was seven per 10,000 cattle placed at a feedlot. Risk factors for a cohort having at least one heart disease death included sex, average cohort arrival weight, year of placement, length of cohort feeding period up until 325 days on feed, and number of cattle received per cohort. Timing of a heart disease death was found to have a mean and median days on feed of 110 days. Cohort demographics associated with the timing of heart disease were average cohort arrival weight which was modified by placement year. Year of placement was also modified by placement quarter on the timing of heart disease death. Steers were found to die later in the feeding phase compared to heifers. The second investigation utilized individual animal treatment records and cohort data to analyze associations of disease treatment and risk of heart disease in feedlot cattle. This study found that cattle were removed from their respective cohort at a rate of nine per 10,000 cattle placed due to heart disease. Furthermore, cattle died with a heart disease diagnosis at a rate of six per 10,000 cattle placed resulting in a total of 15 heart disease cattle per 10,000 cattle received that did not finish with their respective cohort. The number of BRD treatments was associated with the risk of heart disease and the magnitude of risk was influenced by average cohort arrival weight. Treating cattle for acute interstitial pneumonia (AIP), BRD, and complex disease was associated with increased risk of terminal heart disease diagnosis. Heart disease risk was influenced by feedlot elevation and average cohort arrival weight. The third and final investigation of heart disease reported risk and timing of right heart failure (RHF) when using a specific case definition in feedlot cattle from Canada and the U.S. These data found that cattle breed (beef, dairy, dairy-cross), type (yearling, calves), treatment of BRD (yes/no), cohort BRD morbidity (0 to 5%, 6 to 12%, 12.1 to 27% and >27%), elevation category, sex, arrival quarter and arrival year were associated with risk of RHF. These data also reported that cattle had an unadjusted risk of RHF of 7.8 cattle per 10,000 cattle placed. Timing of RHF death was on average of 179 days on feed and had a median of 174 days on feed unadjusted. The demographic and risk factors used to associate risk with RHF were also found to be associated with timing of RHF and several interactions were evaluated for their influence of timing of RHF. The fourth investigation utilized individual and cohort data from 10 US feedlots. Cohorts were divided into HIGH (≥ 15% BRD) morbidity or LOW (<15% BRD) morbidity based on cumulative first treatment BRD within a cohort. Cohorts were clustered on the cumulative timing of their respective first treatment BRD. Descriptive and statistical analysis were performed on all groups from the cluster analysis as well as the inclusion of cohorts that did not report any treatments for BRD. Results indicated shrink, average cohort arrival weight, ADG, sex, death loss, railed cattle, and number of cattle received were associated with clustering group. In conclusion, the current research reported novel information on feedlot heart disease and descriptions of the temporal patterns of BRD from high and low BRD cohorts as well as data supporting previous findings of the respective diseases. These data reported many different demographic and risk factors with heart disease risk and timing, as well as, associating with specific clustering BRD timing patterns. This information could be useful in future research

Evaluation of Byproduct Combinations on Feedlot Performance, Carcass, and Fecal Characteristics

The first experiment compared inclusion levels of a 1:1 blend of Sweet Bran (SB) and dried distiller's grains (DDGS) byproducts in a dry-rolled corn feedlot ration on performance, carcass merit, and fecal characteristics. Heifers (n = 108; initial BW = 324� 13.6 kg) were blocked by BW, randomized to treatment, and fed for 142 d. Treatments were control (CONT, 8% DDGS), intermediate with 22% SB and 22% DDGS (INTERM), and all byproduct with 44% SB and 44% DDGS (ALL). Dry matter intake resulted in a quadratic response (P = 0.05) and ADG and carcass adjusted ADG tended to result in quadratic responses (P > 0.08) with INTERM being the highest. Final body weight was not different (P > 0.15) on a live basis, but was greater (P 0.19) in carcass characteristics. These data indicate that replacing dry-rolled corn in a finishing diet with a 1:1 blend of SB and DDGS increases feed efficiency and HCW without altering ADG calculated with live weights. Fecal pH and scores increased linearly (P 0.20) among treatments in overall ADG, G:F, or DMI. No differences (P > 0.06) were detected in HCW, dressing percentage, marbling score, KPH or USDA Yield Grade. Data suggests that when fed at 30% of the finishing diet DM, corn DDGS and sorghum WDGS can be blended or exchanged with no impact on finishing performance or carcass characteristics.Department of Animal Scienc

A cadaveric study of the anterolateral ligament: re-introducing the lateral capsular ligament.

PURPOSE: The purpose of this study was to verify and characterize the anatomical properties of the anterolateral capsule, with the aim of establishing a more accurate anatomical description of the anterolateral ligament (ALL). Furthermore, microscopic analysis of the tissue was performed to determine whether the ALL can morphologically be classified as ligamentous tissue, as well as reveal any potential functional characteristics. METHODS: Three different modalities were used to validate the existence of the ALL: magnetic resonance imagining (MRI), anatomical dissection, and histological analysis. Ten fresh-frozen cadaveric knee specimens underwent MRI, followed by anatomical dissection which allowed comparison of MRI to gross anatomy. Nine additional fresh-frozen cadaveric knees (19 total) were dissected for a further anatomical description. Four specimens underwent H&E staining to look at morphological characteristics, and one specimen was analysed using immunohistochemistry to locate peripheral nervous innervation. RESULTS: The ALL was found in all ten knees undergoing MRI and all nineteen knees undergoing anatomical dissection, with MRI being able to predict its corresponding anatomical dissection. The ALL was found to have bone-to-bone attachment points from the lateral femoral epicondyle to the lateral tibia, in addition to a prominent meniscal attachment. Histological sectioning showed ALL morphology to be characteristic of ligamentous tissue, having dense, regularly organized collagenous bundles. Immunohistochemistry revealed a large network of peripheral nervous innervation, indicating a potential proprioceptive role. CONCLUSION: From this study, the ALL is an independent structure in the anterolateral compartment of the knee and may serve a proprioceptive role in knee mechanics

Heterosis and inbreeding in the progeney of genetically diverse parental clones of Festuca arundinacea Schreb

The response of maturity, vigor, plant spread, plant height, three forage harvest yields, and total forage yield to heterosis and inbreeding was studied in tall fescue. Parent clones selected for diverse anthesis date, origin, and morphology were separated into two groups based on anthesis date, those having early maturity and those having late maturity. Parents, single-cross (SX), and first generation selfed (S₁) progeny were field evaluated. Parents, S₁, and SX progeny were space planted on a . 914 x 1.219 meter basis at the Hyslop Agronomy Field Laboratory, Corvallis, Oregon, in September, 1969. A randomized block design having four blocks and 14 plant rows as entries was used. Data were collected during the spring, summer, and fall of 1972. Single-cross progeny had a mean performance better than their midparents ' mean performance for all characteristics, with all differences significant except for plant height and third harvest forage yield. Single-cross progeny averaged 7. 03, 13. 18, 13. 50, 3. 89, 42. 93, 51. 72, 15. 14, and 37. 12 percent better than their midparents for maturity rating, vigor rating, plant spread, plant height, first, second, and third harvest forage yield, and forage yield, respectively. There was a greater frequency of individual single-crosses that exhibited significant heterosis in the early x late group than in either the early x early or late x late groups. In addition the average heterotic response of the early x late group was consistently greater than that of either of the other two groups. Thus it appears significant heterosis is more likely to occur, and is likely to be of a greater magnitude, in the progeny of parents having maturity differences, and presumably, greater genetic differences. Significant variation occurred among the single-cross maturity group means for all characteristics with the early x early single crosses most often being the better performers. Consequently the additional heterosis observed in the early x late group was usually insufficient to bring performance of this group up to that of the higher performing but less heterotic early x early single-crosses. This suggests heterosis may be of little practical importance. Inbreeding depression of S₁ progeny was significant for all characteristics. The inbreeding depression was of the greatest magnitude in the progeny of the early parents. Performance of early parents and early S₁ progeny was generally better than that of their late counterparts. Heritability estimates were high, particularly those obtained by regressing single-cross progeny on midparents, although two did not differ significantly from zero. The coefficients of determination for the same associations were likewise high, with over 70 percent of progeny variation being explained by linear association with parents for most characteristics. As superior progeny came from superior parents, this high degree of association suggests clonal evaluation may be an effective screening method in tall fescue. There was strong association among the characteristics of maturity rating, plant spread, plant height, first and third forage yield, and total forage yield, with the lowest of these coefficients of determination, R² = .6031, occurring between maturity rating and plant spread. Vigor rating, second harvest yield, seedling vigor index, and panicle number showed little association among themselves or among the other characteristics, with the highest association, R² = . 3599, occurring between panicle number and third harvest yield. Seed yield was moderately associated with forage characteristics, with R² values of about .5000, but showed no association with panicle number