Unlike infrastructure-based networks, mobile ad hoc networks consist of nodes independent of any infrastructure. Cooperation among these nodes is essential for the sustenance of multi hop communication. However, battery and bandwidth constraints may lead nodes in an ad hoc network to adopt energy- and bandwidth-conserving strategies. As routing and packet forwarding are end results of cooperation, network performance is affected when nodes in the network behave selfishly to conserve their resources. Our work involves characterizing selfish behavior by nodes in ad hoc networks and assessing the effectiveness of adopting tit for tat based strategies, which are meant to discourage selfish behavior in the network. We show that in an ad hoc network where other nodes act selfishly to conserve their resources, a node can benefit by adopting a generous tit for tat strategy. We also show that a node can gain benefit by avoiding selfish nodes in an ad hoc network, adopting a strategy that we call generous tit for tat with selfish avoidance (GTFT-SA) To analyze the effectiveness of cooperation strategies in selfish ad hoc networks we create an emulation environment based on virtualization. Such an emulation environment is more flexible to changes and is simpler to replicate than real life testbeds, while providing higher fidelity than simulations. / Master of Science

This thesis explores the use of generous behaviour as a costly signal to convey information about an unobservable social characteristic to other individuals in one's social environment. Building on recent contributions in this spirit, I develop a theoretical framework that contrasts signaling activities without social benefits with activities that benefit the observers in situations in which individuals compete for access to a scarce social good. The objective of the first part of the thesis is to characterize the possible separating equilibria in each case. While one obtains a multiplicity of equilibria when the agents employ neutral signals to convey information, one can make a unique prediction with respect to the individuals' equilibrium behaviour if they use beneficial signaling activities, the agents are of two discrete types, behave symmetrically within their respective types, and the observers of the signals adopt non-decreasing beliefs vis-à-vis the signalers' relative quality. In view of their sharp divergence, the second part of the thesis investigates experimentally the precision of these predictions. The results provide support for many elements of the theory. Among others, the behaviour of individuals in the treatments with beneficent signals is much more closely in line with the theoretical predictions than expected given the complexity of their behavioural implications, especially when it comes to the similarity of the participants' behaviour within them. Behaviour in the treatment with neutral signals, in turn, is consistent with multiple equilibria. The final part of the thesis explores what kind of signaling activity individuals trying to communicate their intentions to potential interaction partners will use in various social settings if given a choice. To this end, the framework developed in the first part is extended to allow the signalers to choose endogenously a signal from a “menu” of signaling activities rather than exogenously prescribing a messaging tool. Besides revealing that the uniqueness result of the framework without choice no longer obtains, the results indicate that the players may, under some conditions, opt for inefficient signals.

The legislative supremacy of Parliament, a dominant characteristic of the Westminster system of government, has for a long time been the basic norm of South African constitutional law. In line with the Westminster prototype, the South African judiciary did not have the power to review the substantive validity of legislation. The creation of a new order, based on a supreme Constitution which entrenches fundamental rights and gives the courts the power to review not on! y the procedural validity but also the substantive validity of legislation, has brought about a significant change. This thesis examines the role of the South African judiciary during the transition from a system of legislative supremacy to one of constitutional supremacy and judicial review. The thesis is based on the interim Constitution of 1993. The entrenchment of fundamental human rights in the Constitution implies a greater role for the judiciary. The judiciary has to apply and interpret the human rights provisions vigorously and fearlessly. The human rights provisions have to be applied and interpreted with a keen awareness that a system of constitutional supremacy differs materially from one of legislative supremacy. In a system of legislative supremacy the intention of the legislature is paramount; in a system of constitutional supremacy the Constitution is supreme and overrides all laws, including Acts of Parliament, which are in conflict with it The doctrine of legislative supremacy has in the past led to a literalist and mechanical application of law; this has had a negative impact on the constitutional role of the South African judiciary. The provisions of a Constitution, especially its human rights provisions, are framed in wide and open ended terms; these need to be elaborated before they can be applied; the nature of these provisions, their purpose and the larger objects of the Constitution are important. The interpretation of the provisions of a supreme Constitution is incompatible with a literalistic and mechanical approach. A purposive and liberal or generous approach is called for. A framework and approach to the interpretation and application of South Africa's Bill of Rights are suggested in the thesis. / Constitutional International and Indigenous Law / LL.D.

Washington National Cathedral sits atop Mt. St. Alban’s hill in Washington, D.C. declaring itself the nation’s cathedral and spiritual home for the nation. The idea of a national church serving national purposes was first envisioned by L’Enfant in the District’s original plan. Left aside in the times of nation building, the idea of a national church slumbered until 1893 when a group of Episcopalians petitioned and received a Congressional charter to begin a church and school in Washington, D.C. The first bishop of Washington, Henry Y. Satterlee, began his bishopric with the understanding that this cathedral being built by the Protestant Episcopal Church Foundation was to be a house of prayer for all people. Using Jasinksi’s constructivist orientation to reveal the one hundred year rhetorical history defining what constitutes a “national cathedral” within the narrative paradigm first established by Walter Fisher, this work utilizes a rhetorical biographical approach to uncover the various discourses of those speaking of and about the Cathedral. This biographical approach claims that Washington National Cathedral possesses an ethos that differentiates the national cathedral from the Cathedral of St. Peter and St. Paul even though the two names refer to the same building. The WNC ethos is one that allows a constant “becoming” of a national cathedral, and this ability to “become” allows for a rhetorical voice of the entity we call Washington National Cathedral. Four loci of rhetorical construction weave through this dissertation in the guiding question of how the Cathedral rhetorically created and how it sustains itself as Washington National Cathedral: rhetoric about the Cathedral, the Cathedral as rhetoric, the Cathedral as context, and Cathedral Dean Francis Sayre, Jr. as synecdoche with the Cathedral. This dissertation is divided into eight rhetorical moments of change that take the idea of a national church from L’Enfant’s 1791 plan of the City through the January 2013 announcement allowing same-sex weddings at the Cathedral and Obama’s second inaugural prayer service. The result of this rhetorical exploration is a more nuanced understanding of the place and how it functions in an otherwise secular society for which there is no precedent for the establishment of a national cathedral completely separated from the national government. The narrative strains that wind through Cathedral discourse create a braid of text, context, and moral imperative that ultimately allows for the unique construction of Washington National Cathedral, a construction of what defines “national” created entirely by the Cathedral.

The legislative supremacy of Parliament, a dominant characteristic of the Westminster system of government, has for a long time been the basic norm of South African constitutional law. In line with the Westminster prototype, the South African judiciary did not have the power to review the substantive validity of legislation. The creation of a new order, based on a supreme Constitution which entrenches fundamental rights and gives the courts the power to review not on! y the procedural validity but also the substantive validity of legislation, has brought about a significant change. This thesis examines the role of the South African judiciary during the transition from a system of legislative supremacy to one of constitutional supremacy and judicial review. The thesis is based on the interim Constitution of 1993. The entrenchment of fundamental human rights in the Constitution implies a greater role for the judiciary. The judiciary has to apply and interpret the human rights provisions vigorously and fearlessly. The human rights provisions have to be applied and interpreted with a keen awareness that a system of constitutional supremacy differs materially from one of legislative supremacy. In a system of legislative supremacy the intention of the legislature is paramount; in a system of constitutional supremacy the Constitution is supreme and overrides all laws, including Acts of Parliament, which are in conflict with it The doctrine of legislative supremacy has in the past led to a literalist and mechanical application of law; this has had a negative impact on the constitutional role of the South African judiciary. The provisions of a Constitution, especially its human rights provisions, are framed in wide and open ended terms; these need to be elaborated before they can be applied; the nature of these provisions, their purpose and the larger objects of the Constitution are important. The interpretation of the provisions of a supreme Constitution is incompatible with a literalistic and mechanical approach. A purposive and liberal or generous approach is called for. A framework and approach to the interpretation and application of South Africa's Bill of Rights are suggested in the thesis. / Constitutional International and Indigenous Law / LL.D.