In cooperative networks, relays cooperate and form a distributed multi-antenna system to provide spatial diversity. In order to achieve high bandwidth efficiency, distributed space-time block codes (DSTBCs) are proposed and have been studied extensively. Among all DSTBCs, this thesis focuses on the codes which are single-symbol maximum likelihood (ML) decodable and can achieve the full diversity order. This thesis presents four works on single-symbol ML decodable DSTBCs. The first work proposes the row-monomial distributed orthogonal space-time block codes (DOSTBCs). We find an upper bound of the data-rate of the row-monomial DOSTBC and construct the codes achieving this upper bound. In the second work, we first study the general DOSTBCs and derive an upper bound of the data-rate of the DOSTBC. Secondly, we propose the row-monomial DOSTBCs with channel phase information (DOSTBCs-CPI) and derive an upper bound of the data-rate of those codes. Furthermore, we find the actual row-monomial DOSTBCs-CPI which achieve the upper bound of the data-rate. In the third and fourth works of this thesis, we focus on error performance analysis of single-symbol ML decodable DSTBCs. Specifically, we study the distributed Alamouti's code in dissimilar cooperative networks. In the third work, we assume that the relays are blind relays and we derive two very accurate approximate bit error rate (BER) expressions of the distributed Alamouti's code. In the fourth work, we assume that the relays are CSI-assisted relays. When those CSI-assisted relays adopt the amplifying coefficients that was proposed in [33] and widely used in many previous publications, upper and lower bounds of the BER of the distributed Alamouti's code are derived. Very surprisingly, the lower bound indicates that the code cannot achieve the full diversity order when the CSI-assisted relays adopt the amplifying coefficients proposed in [33]. Therefore, we propose a new threshold-based amplifying coefficient and it makes the code achieve the full diversity order two. Moreover, three optimum and one suboptimum schemes are developed to calculate the threshold used in this new amplifying coefficient. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-06-27 19:07:47.066

A multi-hop, amplify-and-forward (AF), cooperative diversity system with K relays is studied. An accurate approximate expression for the symbol-error-rate (SER) is derived for the multi-hop system. Also, a lower bound for the outage probability of the system, that is tight throughout nearly the entire signal-to-noise ratio (SNR) range, is presented. Neither an SER expression nor an outage probability expression had previously been reported in the literature for the multi-hop system. To assist in the derivation of the SER expression, the cumulative density function (CDF), probability density function (PDF), and moment generating function (MGF) are found for the random variable (RV), Z = X Y / (X + Y + c), where X and Y are RVs which have PDFs that are sums of terms of the form x^n exp(-b x). It is shown that with the CDF, PDF, and MGF of this type of RV, it is possible to derive an expression for the SER of the multi-hop system for several important scenarios with respect to what type of fading is present in the channels of the system. To assist in the derivation of the lower bound of the outage probability, the CDF is found for an interesting new RV, presented in a recursive formula, that is used to represent the upper bound of the instantaneous end-to-end SNR of the multi-hop system. These mathematical results are useful beyond the scope of the multi-hop system researched in this thesis. Also, many of the results found in this thesis for the previously-scarcely-studied multi- hop sytem are shown to be generalizations of results that had been found for the previously-often-studied two-hop, AF, cooperative diversity system with K relays. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2009-08-04 12:02:41.495

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The research tests the potential of the Community Supported Agriculture Financing Method (CSAFM) as a viable alternative to traditional debt financing in Agriculture. The CSAFM provides the Farmer with a source of non-farm equity capital and an element of risk reduction which are supplied by each Member/Investor (M/I). By receiving cash up-front (from selling shares of the harvest) several months prior to seeding, costs of inputs are covered and financing costs on operating capital eliminated. Moreover, the Farmer is guaranteed a market and price for his harvested produce. M/I benefits include receiving organic produce at a discount to retail market prices. / A case study of a Canadian CSA "ABC" operation is presented to show the impact of the share price on the farm budget and M/I returns. A detailed budget analysis, demonstrates the benefits of CSA marketing versus marketing through an organic wholesaler, and CSA financing versus line of credit or loan financing. Although it was discovered that the share price was not calculated from a total budget, the Farmer was still better off with the CSAFM, which increased revenues by 34.0%, eliminated financing costs equal to 1.1% to 3% of total revenues, and yielded a net balance between $1,875.25 to $2,057.66 more than traditional techniques. For the M/I, data were collected during the 12 week contract period to value each weekly CSA delivery against both a non-organic market value (NOMV) and an organic market value (OMV). The M/I's (OMV) return on the $180 share price was 38.9%. / Given the results of the study, the CSAFM does qualifies as an alternative financing method in agriculture, displaying a win-win relationship for both Producer and Consumer.

<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>

Cooperatives are a means through which farmers may gain economic power by reducing unit transaction costs associated with production, marketing and distribution of products. In South Africa, cooperatives are promoted as a means of advancing economic development in rural areas through empowerment, development of income generating activities, improvement of human resource capacity, and increased savings and investment. The new Cooperatives Act 14 of 2005 was enacted in August 2005 to promote the role of cooperatives as organisations for pro-poor development in South Africa and to increase their chance of survival in the economy. This study uses a New Institutional Economics (NIE) framework to analyse the Cooperatives Act and its worth as a vehicle for promoting pro-poor development. A hypothetical cooperative, predicated by the new Act, was analysed using the NIE to identify institutional problems likely to constrain the collective efforts of small producers. A case study approach was then used to analyse three production cooperatives in KwaZulu-Natal that were registered post August 2005 and still operational in 2008. Interviews were conducted with individual members, directors and project managers (where applicable) between May and July 2008. Open-ended questions provided the flexibility needed to explore the institutional roots of problems identified by respondents. Free-rider, horizon, portfolio, control and influence problems were identified in the case studies. These problems, which stem from ill-defined voting and benefit rights, resulted in low equity investment, low investment in long term assets, a preference for current cash flows rather than future investment, and social conflict – all of which constrained the competitiveness and growth prospects of the cooperatives studied. In an attempt to mitigate these problems, two of the cooperatives shed their poorest members, a solution which is not consistent with the objective of pro-poor economic development. Additionally, two cooperatives opted to create their own rules to reward investors with capital gains - an institutional arrangement that is not permitted by the new Act. It is concluded that the new Act should be amended to give cooperatives greater flexibility in their institutional arrangements. In particular, cooperatives should be allowed to issue tradable equity shares that offer benefits proportional to shareholding. If these tradable equity shares carry voting rights and are offered to non-patron investors, aggregate voting rights conferred on these non-patron investors should be capped to prevent loss of control by patron members. It is further recommended that the same level of start-up support should be made available to all producer groups that formally register their business, regardless of the business model chosen, and that member empowerment should be an essential requirement for registration and public funding. Keywords: Agricultural Cooperatives, Cooperatives Act, New Institutional Economics, Case Study / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

Transmit diversity usually employs multiple antennas at the transmitter. However, many wireless devices such as mobile cellphones, Personal Digital Assistants (PDAs), just to name a few, are limited by size, hardware complexity, power and other constraints to just one antenna. A new paradigm called cooperative communication which allows single antenna mobiles in a multi-user scenario to share their antennas has been proposed lately. This multi-user configuration generates a virtual Multiple-Input Multiple-Output system, leading to transmit diversity. The basic approach to cooperation is for two single-antenna users to use each other's antenna as a relay in which each of the users achieves diversity. Previous cooperative signaling methods encompass diverse forms of repetition of the data transmitted by the partner to the destination. A new scheme called coded cooperation [15] which integrates user cooperation with channel coding has also been proposed. This method maintains the same code rate, bandwidth and transmit power as a similar non-cooperative system, but performs much better than previous signaling methods [13], [14] under various inter-user channel qualities. This dissertation first discusses the coded cooperation framework that has been proposed lately [19], coded cooperation with Repeat Convolutional Punctured Codes (RCPC) codes and then investigates the application of turbo codes in coded cooperation. In this dissertation we propose two new cooperative diversity schemes which are the Repeat-Punctured Turbo Coded cooperation and coded cooperation using a Modified Repeat-Punctured Turbo Codes. Prior to that, Repeat-Punctured Turbo codes are introduced. We characterize the performance of the two new schemes by developing the analytical bounds for bit error rate, which is confirmed by computer simulations. Finally, the turbo coded cooperation using the Forced Symbol Method (FSM) is presented and validated through computer simulations under various inter-user Signal-to-Noise Ratios (SNRs). / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2008.

This dissertation describes a research study that investigated cooperative inquiry as a strategy for professional learning of inner-city school principals in a large urban centre in Western Canada. The study attempted to identify the central issues of concern and means of redress for school leaders in high-poverty communities, many of which focused on educational leadership, school management, the context of their schools within impoverished communities, and the challenges of personal well-being. The findings suggest that cooperative inquiry was an effective strategy in that the approach was participatory, democratic, empowering, life-enhancing, and fostered community-building among participants. The findings also suggest that the approach was effective in that it was grounded in the action research cycle of planning, action, observation, and reflection. The study further examined the use of dialogue as a means of constructing knowledge regarding these issues, and identified the ways in which such knowledge impacts upon the professional practice of these principals. Findings suggest that participants gained knowledge from each other, offered knowledge from others, constructed knowledge together as a group, and developed deeper understandings of their own perspectives. Findings also suggest that meaning is lost when dialogic interactions are transcribed into print. Thus, dialogue is a form of communication in and of itself, one that cannot simply be transformed into the written word without losing part of that dialogic essence. Further, this study posits that dialogue has unique power to be both a process for meaning making, as well as an ontological means of clarifying one’s own sense of reality.

This study explores the effect of implementing expert-developed concept maps and cooperative learning, as compared to direct instruction and cooperative learning, on student learning, experiences and perceptions. Using a mixed-methods research design, data was collected to determine the impact of these combined instructional strategies on students learning as measured by examination scores. Surveys were used to gather data on students' thoughts and feelings towards group work and concept mapping. Finally, a pre- and post-survey was used to determine if instructional strategies impacted students' perceptions of accounting. The results of the study show a significant difference in students learning as measured by examination scores between the treatment and control group. The majority of students reported a preference for group work as well as expert-developed concept maps. Overall students' perceptions of accounting declined in both the treatment and control group.

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