Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 31, 2008) Includes bibliographical references (p. 185-197).

Basaltic volcanism in the form of small-volume, subaerial and subaqueous eruptions have occurred in the Wells Cray—Clearwater area of east central British Columbia. These eruptions have been dated by the K-Ar method and by relationships to dated glaciations. The oldest known eruption may be as old as 3.2 Ma, but is more likely 2 Ma or less. The youngest eruptions are less than 7560 ± 110 radiocarbon years. The most extensive basalts are valley-filling and plateau-capping flows of the Clearwater unit, which are Pleistocene in age and greater than 25 km³ in volume. The deposition of flows of the Clearwater unit has overlapped at least three periods of glaciation. The interaction of glacial ice and basaltic magma has been recorded in the form of tuyas, ice ponded valley deposits and subglacial mounds (SUGM). In a few place glacial till has been preserved beneath basalt flows. Flows of Wells Gray—Clearwater suite appear to have erupted from vents that are both spatially and temporally separated. The individual eruptions were of low volume (<1km³) and chemically distinct from one another. Major element composition is variable but the lavas are predominantly alkalic. Olivine is the predominant phenocryst phase. Plagioclase and augitic clinopyroxene rarely occur as phenocrysts, but both minerals are ubiquitous in the groundmass. Orthopyroxene was not seen in any of the samples. Flows appear to have erupted with minimal crystal fractionation or crustal contamination. The range of compositions seen in the suite is best explained by a process of partial melting and the progressive depletion of the mantle source by earlier melts. Progressive depletion of the mantle source was coupled with enrichment of parts of the mantle in K as well as some lithophile and siderophile elements. Increasing alkali content may have triggered the highly enriched eruptions of Holocene age that, despite very low degrees of partial melting, were capable of reaching the surface. Overprinting the effects of partial melting are inherited heterogeneities in the source zone of the magmas. Based on whole-rock chemistry the magma source appears to be a highly depleted region similar to that which produces the most depleted mid-ocean ridge basalts (MORB). The zone is, however, capable of producing large volume (≃ 15%) partial melts and has not been isotopically depleted to the same extent as MORB source regions. Isotope analyses of ⁸⁷Sr/⁸⁶Sr, ¹⁴³Nd/¹⁴⁴Nd and whole-rock Pb indicate that the magmas may be derived from a remnant of subducted oceanic lithosphere which has been variously depleted by the prior generation of basaltic melts. Isotopic enrichment above the level seen in MORB's is due in part to crustal contamination. The isotopic results are very different than those obtained from samples erupted through thin, allochthonous crust in the Intermontane Belt and may be explained in part by generation of the magmas in oceanic material which was subducted when allochthonous crust lay against the parautochthonous rocks underlying the Wells Cray—Clearwater area. The alkali olivine basalts of the Wells Cray—Clearwater area have erupted onto a tectonically active surface. A peneplain (erosion surface), formed in Eocene-Miocene time has been uplifted since the Miocene and uplift may be continuing. This uplift is in response to an elevated geothermal gradient which may be due to crustal extension. This crustal extension may be similar to that which occurred in the Eocene. The elevated geothermal gradient and reduced pressures attendant with recent uplift and erosion may have initiated basaltic volcanism in the region, rather than a fixed mantle hot spot as proposed in earlier work. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

The diploma thesis deals with open source implementations of IMS technology. The theoretical part describes the functioning of IMS and its architecture, including the protocols used, the process of registration and connection establishment, as well as potential security threats to IMS systems. Two open source IMS projects were selected, Open IMS Core and Project Clearwater, on which the work is focused. In its next part, the diploma thesis deals with the description of selected open source IMS projects, this part also includes a description of the implemented security of both projects and a detailed procedure of system installation with any necessary configuration. In its practical part, the diploma thesis focused on performance testing of selected projects using the Abacus 5000 hardware tester. First, initialization tests were performed, which verified the possibility of communication between the tester and the tested projects. Subsequently, it was possible to perform performance testing of selected projects. In performance testing, emphasis is placed on system stability, performance in the area of call set-up speed and response time of SIP messages and speed of user registration in the network, at different load levels. The systems have been tested for both call set-up and user registration. Part of the testing is also the implementation of the flood DoS inviteflood attack and the system's response to the increasing intensity of the attack. The last chapter is devoted to the comparison of selected IMS projects, where the test results are clearly presented. This chapter is partly based on publicly available information, such as the technical documentation of individual projects and possibly publicly available mailing lists. Part of the diploma thesis is also a laboratory task in which the student tries to work with Open IMS Core. The laboratory task focuses on the process of creating a user and his registration in the IMS network, establishing a call between individual users and internal routing in IMS networks. The task focuses mainly on signaling processes within the implemented tasks.

The United States Navy's involvement in the Vietnam War, especially its role in the region's inland waterways, has long been an overshadowed aspect of the conflict. Most histories ignore or minimize the Navy's contribution, especially its river patrol or 'brown water' role. Through archival and library research as well as interviews with U.S Navy Vietnam War veterans this thesis demonstrates the vital role played by the brown water navy in the northern provinces of South Vietnam. A key but understudied component of this effort was Task Force Clearwater, an improvised brown water fleet that-along with the maritime logistics campaign that it supported-would prove essential for the successful defense of South Vietnam's northernmost provinces and demonstrate the vital importance of inland naval power. Task Force Clearwater and its supported maritime logistics effort form a little explored component of the U.S. Navy's role in South Vietnam. A brown water task force that proved essential for the successful defense of the northern provinces of I Corps, Clearwater repeatedly demonstrated the vital importance of inland naval power and the critical need for reliable and protected routes of supply. The task force revealed many lessons that had been long understood, forgotten, and then relearned by the U.S. Navy, among them that control of inland waterways was perhaps the most advantageous form of logistical supply in war. Created in part to satisfy the ancient maxim of "keeping the supply lines open", the task force's role broadened with time. In the course of its existence the men and boats of Clearwater would provide not only the tools of war in I Corps but also provide key lessons for the future.