Ice stream research has gained momentum in the last decade due to the increased need to understand ice sheet dynamics and instability and, by extension, the role ice streams have on climate change and sea level rise. Although significant progress has been made recently in understanding the role of ice streams in ice sheet dynamics, much remains to be done for documenting and understanding paleo-ice stream records. This is especially true for terrestrial paleo-ice streams like those that operated in the southwest Laurentide Ice Sheet. In previous studies evidence was shown for at least two large paleo-ice stream systems in southern Saskatchewan and a model was proposed involving major glacial dynamics shifts during the Late Wisconsinan linked to ice streaming in the Prairies. The goal of this research is to further characterize drift provenance and to verify sediment-landform assemblages that are central to the proposed reconstruction. This is done through spatial analysis of sediment and landform characteristics (e.g. compositional data, till fabric, landform identification). Provenance is also investigated using radiometric data and 40Ar/39Ar dating of hornblende grains. All of the data are geo-referenced in GIS to examine the spatial relationships. Results show spatially consistent patterns that fit within the structure of the proposed ice stream model. Ten assemblages were delineated, some showing landform evidence of southwestern and southeastern flow, while others show an older western signature through compositional data. The ice flow dynamics were characterized by a combination of landform evidence and compositional data, where three distinct ice flow phases can be seen. Of these three flow phases, two can be characterized by paleo-ice streams. The older south westward Maskwa system flowed against the regional slope, creating a large area of mega-scale glacial lineations, as well as transverse ridges, and was bound on either side by hummocky terrain. The preservation of the southwest Maskwa system was due to the abrupt shift to the southeastward Buffalo system. The Buffalo system captured the subglacial water from the Maskwa causing its shutdown, which fed the James Lobe until it collapsed. The Buffalo paleo-ice stream was the youngest and least stable of the two systems, as shown in the cross-cutting landform evidence. This approach combines multiple methods of analysis to go beyond the geomorphologic evidence to test the main underlying assumptions of paleo-ice stream landsystem models. This is critical if we are to understand the processes involved in the formation of paleo-ice streams and to reconstruct their evolution. Further characterization of the paleo-ice stream systems in the Prairies is critical to improve our understanding of how large ice sheets, like the Laurentide Ice Sheet, evolved and eventually collapsed.

Monitoring successful urban stream restorations can provide guidance for best practices for restoration design. My case study was located at Critter Creek, a tributary to the Grand River, in northeast Waterloo, Ontario, Canada, where due to high flow and tight meanders, six constructed offline ponds have become connected to the main stream and are now online ponds. This project aimed to evaluate how these online (formerly offline) ponds are affecting the restoration of the stream. The majority of research on this topic has concentrated on ponds specifically constructed for stormwater management or on urban restored streams without ponds. In many restoration plans, offline ponds are proposed to compensate for cut-fill balances and/or for habitat diversity. The relationship of these offline ponds to the function and ecology of the channel has not often been assessed. Benthic macroinvertebrates were used as indicators of restoration as a proxy for water quality. Using a Surber sampler, samples were collected in the reaches of the stream upstream of the inlet and downstream of the outlet of each pond. Comparative samples were taken from waterbodies that provided a restored stream without offline ponds and a reference stream. In the laboratory, all benthic macroinvertebrates were identified to the Family level. Ecology-based metrics (EPT, functional feeding groups, etc.) and an index (Hilsenhoff FBI) were used to characterize the assemblages. The Percent Model Affinity (PMA) Method was used to determine the impairment of the streams and Mann-Whitney tests were conducted to determine if differences existed between the samples taken close to the ponds and those not close to the ponds. Those tests were also conducted to determine differences between Critter Creek and the reference and other restored stream. PMA results from monitoring from previous years indicated that Critter Creek was an impaired stream, and this research shows that the stream is still impaired with PMA values less than 33.23% for 83 of 89 samples. Mann-Whitney tests showed that the location in Critter Creek, whether it be adjacent to an online pond or not, does not have an effect on the benthic assemblages. They also indicate that the composition of the benthic assemblages in Critter Creek has not reached the same stage as those in Laurel Creek, the reference stream, or Clair Creek, the other restored stream. While the habitat and functional requirements of organisms between all three streams is similar, the water quality present in Critter Creek is much lower than in the other two streams. Further monitoring could be completed to determine the trajectory of the benthic macroinvertebrate assemblages in this restoration. However, given that monitoring for the past 10 years has shown that the ecosystem integrity of Critter Creek is not improving, it is advised that action be taken now to improve the stream restoration. The concepts of urban ecology were addressed in this study and a wider-scope monitoring program could be completed to determine the impact of urbanization on the restoration of Critter Creek.

Streaming data have gained considerable attention in database and data mining communities because of the emergence of a class of applications, such as financial marketing, sensor networks, internet IP monitoring, and telecommunications that produce these data. Data streams have some unique characteristics that are not exhibited by traditional data: unbounded, fast-arriving, and time-changing. Traditional data mining techniques that make multiple passes over data or that ignore distribution changes are not applicable to dynamic data streams. Mining data streams has been an active research area to address requirements of the streaming applications. This thesis focuses on developing techniques for distribution change detection and mining time-changing data streams. Two techniques are proposed that can detect distribution changes in generic data streams. One approach for tackling one of the most popular stream mining tasks, frequent itemsets mining, is also presented in this thesis. All the proposed techniques are implemented and empirically studied. Experimental results show that the proposed techniques can achieve promising performance for detecting changes and mining dynamic data streams.

This thesis proposes a merging mechanism for multiple video surveillances in TCP networks. Merging video streams not only can benefit network administration but also reduce the waste of bandwidth. In this thesis, we design a Video-Merging Gateway (VMG) between cameras and control center to merge two video streams transmitted from cameras and received by control center. In the merging mechanism, we develop two modes: Interleave and Overlay. Interleave mode includes two operation types: Single Frame and Proportional. The former merges video streams by interleaving frames one by one from two cameras, and the latter merges video streams according to an FPS (frame per second) ratio between two cameras. Overlay mode vertically displays two video streams in separate frames on the web browser. We implement VMG on a Linux platform. In the interleave mode, we recalculate both the sequence number and the Ack number of a video packet, and create Ack packet for dropped frames while merging two TCP video streams. In the overlay mode, we modify the decoding messages in the frames and separate data between two video streams to avoid decoding errors. Finally, we analyze the complexity of merging algorithms. By carefully determining the timing for responding the created Ack based on Retransmission Time Out (RTO), packet retransmition can be avoided. In addition, we found out that the number of instructions to execute the algorithm is increased by multiple integers along with the picture sizes under interleave mode. As for overlay mode, the number of instructions is increased linearly along with the payload length and the total amount of data and Ack packets.

Nowadays, X86 CPU all have superscalar computing ability. Superscalar architecture can fetch, execute and commit more than one instruction per cycle. And it helps a lot to explore more instruction level parallelism. If a superscalar processor fetches instructions inefficiently, its performance speedup ratio will be limit. Program flow is not continuous. It is one of main reasons that Front-End can¡¦t fetch efficiently. And it is useless to get more speedup by enlarging fetch capacity of Front-End or other units. In this thesis, we present a new structure of branch target buffer and instruction stream buffer. They have abilities to predict advance branch information and reassemble cache lines. Front-End could fetch more valid instructions in a cycle by reassembling original line and line which contains instructions of the next basic block. The simulation and implement results show that we can get 43.2% speedup in fetch efficiency with 64 bytes cache line size and 6 fetch capacities. And 3.6 valid instructions per cycle with ABP buffer which buffers 4 cache line.

SCTP (Stream Control Transmission Protocol) was proposed by IETF. It shows superior extensibility and compatibility as compared to other transport layer protocols, such as TCP and UDP. In addition, it supports multi-streaming and multi-homing. Although an SCTP connection can convey many video streams from different applications, it lacks the provision of different QoS for different streams in the same association. On the other hand, more and more mobile devices are equipped with multiple network (e.g., UMTS/WLAN) interfaces to transmit packets over 3G cellular networks or wireless local area networks. This thesis presents a dynamic chunk adjustment scheme for SCTP-based video streaming in an integrated UMTS and WLAN network. The proposed scheme can support QoS guarantees for different streams in an SCTP association whenever a mobile node moves across the two networks or remains service by either network. Besides, when a mobile node roams from a WLAN to a UMTS, the proposed ¡§deassociation¡¨ capability is applied to increase the channel utilization in 3G cellular networks. Performance evaluations on NS-2 are presented to demonstrate the effectiveness and the advantage of our proposed scheme over the original SCTP.

Because of the restriction on structure hazard and instruction data dependence, the quantity of NOP instructions fills up a program for VLIW Architectures. This problem causes a waste of program memory, so that an instruction compression mechanism is a must for VLIW Architectures. The vectorized instruction in DVB-T (Digital Video Broadcasting - Terrestrial) DSP will collect the discrete vectors into one continuous vector. This mechanism is based on the software-pipeline of the zero overhead looping mode. It is important to improve the efficiency of instruction fetcher. Additionally, the branch instruction can cause the non-continuous behavior of a program and the damage of the efficiency of instruction fetcher. The mechanism of compressed instructions causes the irregular length of long instruction in fetch packet. The problem becomes difficult designed. The thesis implements a design of improving instruction stream buffer, which can keep the repeat block in buffer. This mechanism overcomes the effects of zero overhead looping and branch instruction. It can also improve the efficiency of continuously fetch instructions. The simulation result shows that the mechanism has a good efficiency in FFT, FIR and DCT.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 137-150). Also available on the Internet.

Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains viii, 96 p. : ill., maps (some col.). Includes abstract. Includes bibliographical references (p. 41-51).

Thesis (M.L.A) -- University of Texas at Arlington, 2008.