This dissertation proposes autonomous robotic strategies for urban search and rescue (USAR) which are map-based semi-autonomous robot navigation and fully-autonomous robotic search, tracking, localization and mapping (STLAM) using a team of robots. Since the prerequisite for these solutions is accurate robot localization in the environment, this dissertation first presents a novel grid-based scan-to-map matching technique for accurate simultaneous localization and mapping (SLAM). At every acquisition of a new scan and estimation of the robot pose, the proposed technique corrects the estimation error by matching the new scan to the globally defined grid map. To improve the accuracy of the correction, each grid cell of the map is represented by multiple normal distributions (NDs). The new scan to be matched to the map is also represented by NDs, which achieves the scan-to-map matching by the ND-to-ND matching. In the map-based semi-autonomous robot navigation strategy, a robot placed in an environment creates the map of the environment and sends it to the human operator at a distant location. The human operator then makes decisions based on the map and controls the robot via tele-operation. In case of communication loss, the robot semi-autonomously returns to the home position by inversely tracking its trajectory with additional optimal path planning. In the fully-autonomous robotic solution to USAR, multiple robots communicate one another while operating together as a team. The base station collects information from each robot and assigns tasks to the robots. Unlike the semi-autonomous strategy there is no control from the human operator. To further enhance the efficiency of their cooperation each member of the team specifically works on its own task. A series of numerical and experimental studies were conducted to demonstrate the applicability of the proposed solutions to USAR scenarios. The effectiveness of the scan-to-map matching with the multi-ND representation was confirmed by analyzing the error accumulation and by comparing with the single-ND representation. The applicability of the scan-to-map matching to the real SLAM problem was also verified in three different real environments. The results of the map-based semi-autonomous robot navigation showed the effectiveness of the approach as an immediately usable solution to USAR. The effectiveness of the proposed fully- autonomous solution was first confirmed by two real robots in a real environment. The cooperative performance of the strategy was further investigated using the developed platform- and hardware-in-the-loop simulator. The results showed significant potential as the future solution to USAR. / Ph. D.

Syftet med denna kunskapsöversikt är att skapa en överblick över aktuell forskning angående metoden kooperativt lärande med fokus på elevernas resonemangsförmåga inom ämnet matematik. Kooperativt lärande är ett arbetssätt att strukturera samarbete mellan eleverna när de lär sig. För att jag ska kunna svara på undersökningsfrågan harjag genomfört systematiska undersökningar i olika databaser, exempelvis Ebsco, Swepub och även sekundära sökningar. Texten är uppbyggt med en inledningsdel som redogör vad kooperativt lärandet och resonemangsförmåga innebär. Sedan har jag sammanställt de funna artiklarna i en tabell och vidare har artiklarna studerats och analyserats. Resultatet visar hur kooperativt lärande kan påverka elevernas resonemangsförmåga positivt, dock krävs det en välstrukturerad undervisning där lärarens kompetens och engagemang är en viktig faktor. Avslutningsvis diskuteras resultaten utifrån framtida yrkesverksamhet och förslag på fortsatt forskning.

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Credit cooperatives make a significant economic and social contribution to development in Kenya. They are unique financial institutions that are jointly owned and democratically controlled by their members. This study explores how members of Kenyan credit cooperatives achieve economic cooperation. A sociological basis of cooperation exists because cooperatives are voluntary associations. Economic cooperation was thus conceptualised as collective economic action that enables individual actors to secure economic benefits through associational membership. An economic sociology perspective provided the theoretical basis for combining the analysis of economic interests and social relations. The study employed a qualitative case study research design involving a rural and an urban credit cooperative. Social capital was used to explore the role of associational features in facilitating collective action while the concept of institutions was used to examine how institutions organize and shape collective action. Each cooperative was conceptualised as a microstructure to enable an analysis of group relations. An analysis of the economic and socio-political context provided the contextual basis for economic cooperation. The findings suggest that shared values and solidarity bonds are important in creating collective economic resources while maintenance of the collective resources depends on regular reciprocity exchanges, effective enforcement and transparent representation. A new regulatory framework that emphasizes prudential standards and economic efficiency has redefined the incentive structure for Kenyan credit cooperatives. It is likely to favour a business rather than a social welfare mentality in the cooperatives. The socio-political context reveals persistent vertical linkages that have resulted in low political and economic power for rural smallholder farmers compared to urban public sector employees. The study concludes that although credit cooperatives have acted as financial catalysts by enabling the participation of disadvantaged groups in the economic sphere, they are also societal mirrors that reflect the broader income and gender inequalities existing in society. The recognition of cooperatives as economic and social organizations therefore contributes to a better understanding of how cooperatives work.

In this dissertation we consider the problem of cooperative sensing for secondary user access to primary user spectrum in cognitive radio systems. Using a fusion center or an access point, the cooperative users decide on the availability of spectrum for their use. Both Neyman-Pearson and Bayes criterion are considered for performance assessment. Our work on the asymptotic performance of counting rules with a very large number of sensors in decentralized detection problem shows that majority logic fusion rule has the same order of performance when compared to the best fusion rule based on the binary decisions received from the observing sensors in a network. In cognitive radio context, very large number of sensors may not be realistic and hence we would like to examine the performance of majority logic and counting rules involving a finite and small number of sensors. Uniformly most powerful test for decentralized detection for testing parameter θ when the observation is a sample from uniform (0,θ) distribution is investigated and it is shown that OR rule has the best performance among all counting rules in error free channel. The numerical study for reporting channel as a binary symmetric channel (BSC) with probability of bit error is also investigated and the results show that 2-out-of-5 or 2-out-of-10 has better performance among other k-out-of-n rules, whenever OR rule is not able to provide a probability of false alarm at the sensor, that lies over (0,1) at a given probability of bit error.

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Control of large groups of robotic agents is driven by applications including military, aeronautics and astronautics, transportation network, and environmental monitoring. Cooperative control of networked multi-agent systems aims at driving the behavior of the group via feedback control inputs that encode the groups’ dynamics based on information sharing, with inter-agent communications that can be time varying and be spatially non-uniform. Notably, local interaction rules can induce coordinated behaviour, provided suitable network topologies. Distributed learning paradigms are often necessary for this class of systems to be able to operate autonomously and robustly, without the need of external units providing centralized information. Compared with model-based protocols that can be computationally prohibitive due to their mathematical complexity and requirements in terms of feedback information, we present an online model-free algorithm for some nonlinear tracking problems with unknown system dynamics. This method prescribes the actuation forces of agents to follow the time-varying trajectory of a moving target. The tracking problem is addressed by an online value iteration process which requires measurements collected along the trajectories. A set of simulations are conducted to illustrate that the presented algorithm is well functioning in various reference-tracking scenarios.

Indiana University-Purdue University Indianapolis (IUPUI) / Biometrics identi es/veri es a person using his/her physiological or behavioral characteristics. It is becoming an important ally for law enforcement and homeland security. Among all the biometric modalities, iris is tested to be the most accurate one. However, most existing methods are not designed for non-cooperative users and cannot work with o -angle or low quality iris images. In this thesis, we propose a robust multi-stage feature extraction and matching approach for non-cooperative iris recognition. We developed the SURF-like method to extract stable feature points, used Gabor Descriptor method for local feature description, and designed the multi- stage feature extraction and matching scheme to improve the recognition accuracy and speed. The related experimental results show that the proposed method is very promising. In addition, two template security enhanced schemes for the proposed non- cooperative iris recognition are introduced. The related experimental results show that these two schemes can e ectively realize cancelability of the enrolled biometric templates while at the same time achieving high accuracy.

Cooperation is a subject which has intrigued the writer for some time. A study of the philosophy, history and accomplishments of the cooperative movement was begun, due to the interest of the study. In Denton County, Texas, the cooperatives have, for the past few years, been making such rapid progress that a study of the inception, growth and success of these societies seemed indicated. In spite of the broad field of study this subjected presented, it seemed necessary to review the cooperative movement before the local cooperatives could be properly interpreted. This was Done. Numerous books and magazine articles pertaining to cooperation were read. In making this library study, the writer tried to delve into the underlying philosophy of the cooperative movement. Those countries in which cooperation has made greatest strides were given particular attention in order to try to find the secret of their success. After this library approach was completed, the various cooperative societies of Denton County were visited. The writer talked with the leaders of the societies, obtained copies of the by-laws of each organization, examined financial statements, and attempted to analyze the purposes, the accomplishments, and the possibilities of the future success of these organizations.