This dissertation presents a Field Programmable Gate Array (FPGA) design methodology that can be used to shorten the FPGA design-and-debug cycle, especially as gate counts increase to many millions. Core-based incremental placement algorithms, in conjunction with fast interactive routing, are investigated to reduce the design processing time by distinguishing the changes between design iterations and reprocessing only the changed blocks without affecting the remaining part of the design. Different from other incremental placement algorithms, this tool provides the function not only to handle small modifications; it can also incrementally place a large design from scratch at a rapid rate. Incremental approaches are inherently greedy techniques, but when combined with a background refinement thread, the incremental approach offers the instant gratification that designers expect, while preserving the fidelity attained through batch-oriented programs. An incremental FPGA design tool has been developed, based on the incremental placement algorithm and its background refiner. Design applications with logical gate sizes varying from tens of thousands to approximately one million are built to evaluate the execution of the algorithms and the design tool. The results show that this incremental design tool is two orders of magnitude faster than the competing approaches such as the Xilinx M3 tools without sacrificing much quality. The tool presented places designs at the speed of 700,000 system gates per second. The fast processing speed and user-interactive property make the incremental design tool potentially useful for prototype developing, system debugging and modular testing in million-gate FPGA designs. / Ph. D.

Field Programmable Gate Arrays (FPGAs) are widely used in prototyping digital circuits. However commercial FPGAs are not very suitable for asynchronous design. Both the architecture of the FPGAs and the synthesis tools are mostly tailored to synchronous design. Therefore potential advantages of the asynchronous circuits could not be observed when they are implemented on commercial FPGAs. This is shown by designing an asynchronous arithmetic logic unit (ALU), implemented in the style of micropipelines, on the Xilinx Virtex XCV300 FPGA family. The hazard characteristics of the target FPGA have been analyzed and a methodology for selftimed asynchronous circuits has been proposed. The design methodology proposes first designing a hazard-free cell set, and then using relationally placed macros (RPMs) to keep the hazard-free behavior, and incremental design technique to combine modules in upper levels without disturbing their timing characteristics. The performance of the asynchronous ALU has been evaluated in terms of the logic slices occupied in the FPGA and data latencies, and a comparison is made with a synchronous ALU designed on the same FPGA.

Disasters due to war and conflict or natural forces are responsible for the 26 million people displaced across the world today. The crisis extends into the temporary, yet indefinite, displacement camps where people live in congested living arrangements, vulnerable to an increased risk of disease, death, and social violence (spousal abuse, rape). Even when chaos subsides, social and physical networks have frayed rendering the temporary displacement camp a permanent home for some. Often, despite this “permanence”, access to adequate services and infrastructure and hence social and economic growth remains in a state of emergency. This thesis proposes that water infrastructure is the key social catalyst for developing these displacement camps into permanent sustainable communities. An urban displacement camp in the town of Gulu, Northern Uganda, is the case study location for a speculative design intervention. During rebel activities from 1996 to 2004, the town of Gulu more than tripled in size, absorbing almost 100,000 displaced people forced to flee their land. These people settled in displacement camps next to, and within the wetlands that border the town on all sides. The urban metabolism of the town has become polluted as the displaced people use, alter and degrade the wetlands because they have no other alternatives. Following the instigation of a peace process in 2006, some people have begun the journey home. However, it is estimated that just over half of these people will continue to live in the squalid camps, without an opportunity to prosper. A strategy is proposed for addressing and subsequently re-defining this urban metabolism. By synthesizing the existing urban fabric with strategies for harnessing the natural landscape, varying scales of water infrastructure are proposed. New opportunities for agricultural production is supported, while the spatial relationships created by the physical structuring of the water infrastructure renews the influence that water collection and distribution has in creating the social locus of a community.

Disasters due to war and conflict or natural forces are responsible for the 26 million people displaced across the world today. The crisis extends into the temporary, yet indefinite, displacement camps where people live in congested living arrangements, vulnerable to an increased risk of disease, death, and social violence (spousal abuse, rape). Even when chaos subsides, social and physical networks have frayed rendering the temporary displacement camp a permanent home for some. Often, despite this “permanence”, access to adequate services and infrastructure and hence social and economic growth remains in a state of emergency. This thesis proposes that water infrastructure is the key social catalyst for developing these displacement camps into permanent sustainable communities. An urban displacement camp in the town of Gulu, Northern Uganda, is the case study location for a speculative design intervention. During rebel activities from 1996 to 2004, the town of Gulu more than tripled in size, absorbing almost 100,000 displaced people forced to flee their land. These people settled in displacement camps next to, and within the wetlands that border the town on all sides. The urban metabolism of the town has become polluted as the displaced people use, alter and degrade the wetlands because they have no other alternatives. Following the instigation of a peace process in 2006, some people have begun the journey home. However, it is estimated that just over half of these people will continue to live in the squalid camps, without an opportunity to prosper. A strategy is proposed for addressing and subsequently re-defining this urban metabolism. By synthesizing the existing urban fabric with strategies for harnessing the natural landscape, varying scales of water infrastructure are proposed. New opportunities for agricultural production is supported, while the spatial relationships created by the physical structuring of the water infrastructure renews the influence that water collection and distribution has in creating the social locus of a community.