The imperfections of the propagation channel due to channel fading and the self-generated noise from the RF front-end of the receiver cause errors in the received signal in electronic communication systems. When network coding is applied, more errors occur because of error propagation due to the inexact decoding process. In this dissertation we present a system called Partial Network Coding with Cooperation (PNC-COOP) for wireless ad hoc networks. It is a system which combines opportunistic network coding with decode-and-forward cooperative diversity, in order to reduce this error propagation by trading off some transmission degrees of freedom. PNC-COOP is a decentralized, energy efficient strategy which provides a substantial benefit over opportunistic network coding when transmission power is a concern. The proposed scheme is compared with both opportunistic network coding and conventional multi-hop transmission analytically and through simulation. Using a 3-hop communication scenario, in a 16-node wireless ad hoc network, it is shown that PNC-COOP improves the BER performance by 5 dB compared to opportunistic network coding. On average, it reduces the energy used by each sender node around 10% and reduces the overall transmitted energy of the network by 3.5%. When retransmission is applied, it is shown analytically that PNC-COOP performs well at relatively low to medium SNR while the throughput is comparable to that of opportunistic network coding. The effectiveness of both opportunistic network coding and PNC-COOP depends not only on the amount of network coding but also on other factors that are analyzed and discussed in this dissertation. / Graduation date: 2011 / Access restricted to the OSU Community at author's request from May 12, 2011 - May 12, 2012

Many development organizations now recognize the importance of culturally sensitive project design and implementation. Unfortunately most of these groups continue to disregard the significance of gender. This qualitative research examines a women's cooperative in rural El Salvador which formed in order to find a means of generating income and to improve the general status of women in this region. One purpose of this qualitative research was to investigate what, if any, economic and social benefits the cooperative members received through their involvement. Another purpose was to analyze the models of development employed by the agencies involved in implementing four cooperative projects, as well as the member's attitudes toward those projects. Data presented in this thesis was collected during a fifteen-month period in 1994 and 1995, and a one-month period in 1998. Twenty-six cooperative members were interviewed in 1998. The four projects investigated include cows and nutrition, land and reforestation, artisan crafts and corn mills. These findings indicate that the empowerment model of development, in which self-reliance is maintained and strategic gender needs are met through mobilizing around practical gender needs, is the most successful. Focusing on local knowledge and preserving the agency of the target population are critical to project success. The findings also show that social power is attained by many women in the cooperative as increased self-esteem and involvement lead to gaining a legitimate voice in community affairs. Economic power, however, is only achieved by maintaining a paid leadership position within the cooperative. This research makes recommendations centered on improved access to credit. / Graduation date: 2001

The primary purpose of this study was t determine the difference in "career progress" and satisfaction between cooperative education/internship graduates and non-coop/ intern graduates of a small, private, non-engineering college. A secondary purpose was to determine which other independent variables (age; gender; SAT score; GPA; percent of related work) contributed significantly to any existing differences. The principle data gathering technique was a mail questionnaire. Graduates from 1986; 1988; and 1990 were sampled allowing for a cross-sectional overview of workforce participation. A 61% usable response rate was achieved using Dillman's (1978) Total Design Method. In general, study data offered little direct evidence supporting co-op/internship participation, although participants held slight advantage.; in regard to length of time to obtain employment; working within the field of study; merit pay increases; job promotions; salary levels; and responsibility levels. Two outcomes, further analyzed, however, indirectly supported co-op/intern participation. 1. Co-op/intern participants, in comparison to nonparticipants, began college at a significant disadvantage in terms of SAT score (866 to 922). At graduation, GPAs were similar (3.14 to 3.19) and following graduation "career progress" occurred at the same rate. How was the disadvantage overcome? It is logical to assume, as Siedenberg (1990) did for salary, that cooperative education enabled "disadvantaged" students to catch up with their peers and compete on an even basis following graduation. 2. Percent of related experience as an undergraduate is a main predictor of "career progress." Those with a higher percent of related work were more likely to be employed within their field of study and were more satisfied. Associated with this, co-op/intern students reported a significantly higher percent of related experience. In addition to the previous findings, gender provided significant results in regard to salaries and promotions. Males "outperformed" females, apparently continuing an existing pattern of gender discrimination. Integrating all of the study data, it seems plausible that females might overcome this gender "disadvantage" by participating in coop and increasing their percent of related work experience. / Graduation date: 1995

In this thesis, we develop a method using fuzzy logic to do cooperative localization. In a group of robots, at a given instant, each robot gives crisp pose estimates for all the other robots. These crisp pose values are converted to fuzzy membership functions based on various physical factors like acceleration of the robot and distance of separation of the two robots. For a given robot, all these fuzzy estimates are taken and fused together using fuzzy fusion techniques to calculate a possibility distribution function of the pose values. Finally, these possibility distributions are defuzzified using fuzzy techniques to find a crisp pose value for each robot. A MATLAB code is written to simulate this fuzzy logic algorithm. A Kalman filter approach is also implemented and then the results are compared qualitatively and quantitatively.

In the first part of the thesis I focus on credit markets in developing countries, and describe the competitive interaction between Microfinance Institutions (MFIs). Microfinance has recently attracted a lot of attention from investors, politicians, scholars and, most of all, people working on development. As a results, a huge number of MFIs are being created all over the world so that, as of today, practitioners reckon that about 100 millions of customers are being served. Remarkably, about 67% of them are women. The reason of this extraordinary effort is that Microfinance is considered the most promising development tool currently available. This belief is based on two important features of Microfinance: (i) It promises to be financially viable (and in some cases even profitable) since poor people have proven to be reliable clients. As a result, Microfinance is potentially a zero-cost development tool. (ii) It hinges on the entrepreneurial abilities of the poor. It is designed to help the poor to help themselves, in their own home countries, by allowing them to use their skills, ideas and potentials. This should progressively make developing countries independent of rich ones' help. The growth of Microfinance has been so fast that many issues and related research questions are still not answered. In my thesis I try to address one of them, that I believe particularly important: the increase of competition between MFIs. As economic theory predicts, competition can have dramatic consequences in terms of borrower welfare, profitability of the institutions and, therefore, on the attractiveness of the business for potential investors, donors and entrants. I use the tools of industrial organization and contract theory to understand these effects, measure them, and give some interesting policy advice. In the first paper, I analyze the effects of entry of a new MFI in a previously monopolistic microcredit market. In order to catch the salient features of financial markets in developing countries, I use a model of asymmetric information and assume that institutions can offer only one type of contract. I consider different behavioral assumptions for the MFIs and study their influence on equilibrium predictions. The model allows showing that competition can lead to equilibria in which MFIs differentiate their contracts in order to screen borrowers. This process can, unfortunately, make the poor borrowers worse off. Interestingly, the screening process we describe creates a previously unexplored source of credit rationing. I also prove that the presence in the market of an altruistic MFI, reduces rationing and, via this channel, affects positively the competitor's profit. In the second paper, I study the effects of competition in those markets in which, due to the absence of credit bureaus, small entrepreneurs can simultaneously borrow from more than one institution. As in the first paper, I analyze an oligopolistic microcredit market characterized by asymmetric information and institutions that can offer only one type of contract. The main contribution is to show that appropriate contract design can eliminate the ex-ante incentives for multiple borrowing. Moreover, when the market is still largely unserved and particularly risky, a screening strategy leading to con- tract differentiation and credit rationing is unambiguously the most effective to avoid multiple borrowing. The result of this paper can also be read as important robustness checks of the findings of my first paper. In the last part of the thesis, I depart from the analysis of developing countries to consider, more generally, the corporate governance of financial infrastructures. The efficient functioning of financial markets relies more and more on the presence of infrastructures providing services like clearing, settlement, messaging and many others. The last years have been characterized by interesting dynamics in the ownership regime of these service providers. Both mutualizations and de-mutualizations took place, together with entry and exit of different players. Starting from this observation, in the last paper (with Joachim Keller), we analyze the effects of competitive interaction between differently owned financial providers. We mainly focus on the incentives to invest in safety enhancing measures and we describe the different equilibrium market configurations. We use a model in which agents need an input service for the financial market they operate in. They can decide whether to provide it them selves by forming a Cooperative or outsource it from a Third Party Provider. We prove that the co-existence of differently governed infrastructures leads to a significant reduction in the investment in safety. In most cases, monopolistic provision is preferable to competition. Moreover, the decision rule used within the Cooperative plays a central role in determining the optimal market configuration. All in all, throughout my thesis, I use the tools of industrial organization and contract theory to model the competitive interaction of the different actors operating in financial markets. Understanding the dynamics typical of developing countries can help in gaining a deeper comprehension of the markets in richer countries, and vice-versa. I am convinced that analyzing the differences and the similarities of financial markets in different regions of the world can be of great importance for economic theorists, in that it provides a counterfactual for the assumptions and the results on which our predictions and policy advices are based.

<p>The thesis took the general question of responsive curriculum development which meets both the needs of work and those of the academy as its starting point. The rationale for the topic flows out of education policy and societal pressures worldwide which are calling for an ever greater responsiveness from higher education to the workplace in the twenty-first century. Responsiveness to work requires collaborative and integrative work between communities of academic and non-academic practitioners. Differences between knowledge and practices at work and within the academy are broadly acknowledged in the literature, yet the ensuing nature and complexity of interactions between these two communities in curriculum design on the ground is poorly understood. A key point is to recognize that integration as such cannot be the goal / the differences remain, but have to turned into productive collaboration and joint development, for example, of a curriculum.</p>

Traditional education system on campus has been using as a legacy over decades to support educational learning. The major change over time has been made by the use of technology supporting students in the academic community. As the majority of students in higher education today belong to the digital-age-student generation, they frequently use online technology to interact with instructors, other learners, and to access online materials. In this study, the result is primarily presented from campus students’ perceptions, to gain a deeper understanding of how social media is being used to support educational and collaborative/cooperative learning. Although, almost all the respondents are frequent social media users, only a quarter of them use such media regularly for academic purposes. Through use of social media in academia, students have encountered with benefits─ as convenience, possibility of interaction anywhere/anytime, time-saving, low price and many others─ in addition to facing to limitations─ such as less effective or spontaneous contact, connection problems, lack of platform compatibility, less creative and innovative thinking, and other issues─ which have been discussed in this study. This thesis adopted a qualitative research and the characterization of knowledge that is used is exploratory research method with the use of interview as a tool for empirical data collection. Twenty interviews have been conducted with Uppsala University higher education students within random subject disciplines. Among many different social media, the most frequent ones used by majority of students are e-mail, a common asynchronous media to interact with instructors and other learners; and Instant Messaging (IM), a synchronous communication way to interact with co-workers, classmates, or group-mates. Furthermore, learners use social media to coordinate their collaborative/cooperative work, share documents and ask questions. Facebook, Wikipedia, YouTube and other popular social media are also sometimes used for educational purposes. The findings indicate that social media seems particularly beneficial for supporting educational learning; though there are some negative aspect and limitations. Learners look at using the technology and social media as a complement to support their studies and collaboration/cooperation. However, not many of them consider using such media as a substitute for face-to-face interactions and the traditional campus education. By drawing on this thesis and the previous studies, proposition on how use of social media supports educational learning in the future has been emerged.

Att samverka mellan olika organisationer i ett rehabiliteringsarbete är inte alltid så enkelt. Stora skillnader finns i både uppdrag, arbetssätt och kompetenser. Den här undersökningen har sitt ursprung i att jag under mina tillämpade studier på arbetsförmedlingen kom till insikt om att problem inom samverkan med andra aktörer uppenbarligen existerade. För att ytterligare problematisera frågan involverade jag såväl handläggare från försäkringskassan, arbetsförmedlingen, samt några primärvårdsläkare i x kommun.. Jag begränsade mig till dessa aktörer eftersom de ofta samverkade. Mitt syfte var att genom en kvalitativ metod, via personliga intervjuer, bringa kunskap om respondenternas egna upplevelser av samverkansarbetet. Resultatet visar på att det finns tydliga fördelar med samverkan, men visade även på stora problem. Inte minst läkaren och försäkringsläkarens väl separerade roller är med dagens regelverk ett stort hot mot den enskilde individens rättssäkerhet och mot en kvalitetssäkrad handläggning. Förändringar av hela eller delar av regelsystemet är några av de önskvärda målen.

Cooperative communications is a class of techniques which seek to improve reliability and throughput in wireless systems by pooling the resources of distributed nodes. While cooperation can occur at different network layers and time scales, physical layer cooperation at symbol time scales offers the largest benefit. However, symbol level cooperation poses significant implementation challenges, especially in the context of a network of distributed nodes. We first present the design and implementation of a complete cooperative physical layer transceiver, built from scratch on the Wireless Open-Access Research Platform (WARP). In our implementation fully distributed nodes employ physical layer cooperation at symbol time scales without requiring a central synchronization source. Our design supports per-packet selection of non-cooperative or cooperative communication, with cooperative links utilizing either amplify-and-forward or decode-and-forward relaying. A single design implements transmission, reception and relaying, allowing each node to assume the role of source, destination or relay per packet. We also present experimental methodologies for evaluating our design and extensive experimental results of our transceiver's performance under a variety of topologies and propagation conditions. Our methods are designed to test both overall performance and to isolate and understand the underlying causes of performance limitations. Our results clearly demonstrate significant performance gains (more than 50× improvement in PER in some topologies) provided by physical layer cooperation even when subject to the constraints of a real-time implementation. As with all our work on WARP, our transceiver design and experimental framework are available via the open-source WARP repository for use by other wireless researchers.

Non-parametric belief propagation (NBP) is a well-known message passing method for cooperative localization in wireless networks. However, due to the over-counting problem in the networks with loops, NBP’s convergence is not guaranteed, and its estimates are typically less accurate. One solution for this problem is non-parametric generalized belief propagation based on junction tree. However, this method is intractable in large-scale networks due to the high-complexity of the junction tree formation, and the high-dimensionality of the particles. Therefore, in this article, we propose the non-parametric generalized belief propagation based on pseudo-junction tree (NGBP-PJT). The main difference comparing with the standard method is the formation of pseudo-junction tree, which represents the approximated junction tree based on thin graph. In addition, in order to decrease the number of high-dimensional particles, we use more informative importance density function, and reduce the dimensionality of the messages. As by-product, we also propose NBP based on thin graph (NBP-TG), a cheaper variant of NBP, which runs on the same graph as NGBP-PJT. According to our simulation and experimental results, NGBP-PJT method outperforms NBP and NBP-TG in terms of accuracy, computational, and communication cost in reasonably sized networks. / COOPLOC / FP7-ICT WHERE2