Thesis (M.A.I.S.)--Oregon State University, 1997. / Typescript (photocopy). Includes bibliographical references. Also available online.

Thesis--Toulouse. / Includes bibliographical references (p. [165]-168).

Thesis--Toulouse. / Includes bibliographical references (p. [165]-168).

Thesis (D. Min.)--Midwestern Baptist Theological Seminary, 1992. / This is an electronic reproduction of TREN, #054-0031. Includes bibliographical references (leaves 162-171).

Thesis (M.S.)--University of Wisconsin--Madison, 1959. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 115-121).

This dissertation is concerned with the analysis of a late portion of the Crescent Beach shell midden (DgRr 1 ) situated on Boundary Bay in the southern Fraser River Delta of British Columbia. The basic objectives of this study are the recovery and analysis of shell midden layers and their constituents to obtain information on Coast Salish subsistence activities, and to initiate a better understanding of shell midden formation. The cultural history of the Strait of Georgia region is viewed as a 5,000 year long Tradition of Coast Salish Cultures. To place the archaeological materials from Crescent Beach in their proper cultural ecological perspective, the environmental, ethnographic and archaeological setting of the site and surrounding region is examined. The historic ecological communities of Boundary Bay are reconstructed and the abundance and availability of species of economic value determined. Ethnographic Coast Salish Culture and economic strategies are examined and possible settlement patterns reconstructed for Boundary Bay. To assist in identifying subsistence activities at Crescent Beach a shell midden model is presented outlining the systemic and archaeological transformation processes responsible for the site's development. In light of this model and the above environmental and ethnographic data the most probable seasons of site occupation are suggested. Archaeological data were recovered by the hand trowel excavation of a block of shell midden layers and the matrix, provenienced within a 0.25 m2 unit, was waterscreened through a 1.45 mm mesh screen. In total some 24 m3 of shell midden weighing 28.8 t were excavated. Recove of midden constituents was accomplished through a multiple tier sampling system. Radiocarbon estimates of 1350 to 480 B.P., place the 31 layers recovered from Crescent Beach in the Developed Coast Salish Culture. Seasonality dating of shellfish growth patterns and analysis of layer constituents indicate the site was a shellfish and herring harvesting camp occupied in February and March. Layers recovered from Crescent Beach reflect shellfish and herring processing (steaming, sorting, refuse discard, and meat preservation) as well as the immediate consumption of other foods. Artifacts indicate the manufacture, mostly in bone and antler, of tools used in fishing, woodworking and hide processing, the latter two activities conducted at the site. Procurement of shellfish, crab and most fish species probably took place along the 3 km stretch of beach south of the site where present ecological communities contain identical resources as found in the site. Petroglyphs and a fort-lookout site also attest to the use of this area. Shellfish were the most common faunal remain, followed by a much lesser quantity of fish, waterfowl and some large mammals. In addition to the Crescent Beach site, the Deep Bay site (DiSe 7) and Shoal Bay site (DcRt 1) may also be seasonal shellfish and herring harvesting camps, and it is suggested that Whalen II (DfRs 3) and the Locarno Beach site (DhRt 6) may have had similar uses. This evidence and the fact additional seasonal sites dating to the Locarno Beach Culture have been identified indicates the Proto-Coast Salish had a specialized economic system by 3,500 B.P. and possibly earlier. Indications of social ranking are also evident by this time. The approach followed in this study indicates accurate information on economic strategies may be obtained from shell middens. Where research is interested primarily in seasonality, settlement pattern and subsistence the controlled excavation of small blocks of shell midden layers, fine mesh water screening, and analysis of small numbers of shell samples will be adequate. This has important implications for the study and resource management of the shell middens of the Strait of Georgia region. / Arts, Faculty of / Anthropology, Department of / Graduate

This doctoral dissertation traces how the Red Cross Movement was able to gain a foothold on the Indian subcontinent and came to play an important part in colonial civil society and in the nation-building process from the last third of the nineteenth century onwards up until the end of the interwar period. Far from being at the mere receiving end, it suggests that India played a crucial role in shaping and making the Red Cross Movement. It argues that India became an important hub of transnational and international Red Cross humanitarianism in Asia. The developments on the subcontinent had deep regional, international and global repercussions and were crucial in transforming the Red Cross into a global movement From the last third of the nineteenth century onwards, Indians started to organise humanitarian missions and institutions to help their co-religionists and co-citizens, but also as an act of claiming citizenship and of stressing their role in the ethical community of humanity. Like the Swiss Red Cross founders, Indian intellectuals too constructed a moral universe couched in universal terms, yet it was rooted in their own moral, geographical and imagined spaces of allegiance and affection. It was based on pan-Asian, pan-Islamic and anti-colonial conceptions of a supranational ethical community. By the end of the interwar period, the different humanitarian initiatives culminated in a distinctively Indian Red Cross and Red Crescent tradition. It recast the Christian mid-nineteenth programme of civilising war into a pan-Asian, anti-colonial, anti-communal and anti-racial internationalist movement that had deep reverberations beyond the Indian locality. It was upon such a humanitarian tradition that Nehru's non-alignment policy was built. By reconstructing a distinct Indian Red Cross and Red Crescent tradition this dissertation attempts to de-centre the rigorously Eurocentric and institutional focus of the current body of research on the Red Cross movement and humanitarianism more generally. It enhances our understanding of the relationship between British imperialism, decolonisation, nation-building in Asia and international and transnational humanitarianism.

<p>Onboard cone beam computed tomography (CBCT) has become a widespread means of three-dimensional target localization for radiation therapy; however, it is susceptible to metal artifacts and beam-hardening artifacts that can hinder visualization of low contrast anatomy. Dual-CBCT provides easy access to techniques that may reduces such artifacts. Additionally, dual-CBCT can decrease imaging time and provide simultaneous orthogonal projections which may also be useful for fast target localization. However, dual-CBCT will suffer from large increases in scattered radiation due to the addition of the second source.</p><p>An experimental bench top dual CBCT system was constructed so that each imaging chain in the dual CBCT system mimics the geometry of gantry-mounted CBCT systems commonly used in the radiation therapy room. The two systems share a common axis of rotation and are mounted orthogonally. Custom control software was developed to ensure reproducible exposure and rotation timings. This software allows the implementation of the acquisition sequences required for the cross scatter avoidance and correction strategies studied.</p><p>Utilizing the experimental dual CBCT system cross scatter was characterized from 70-145 kVp in projections and reconstructed images using this system and three cylindrical phantoms (15cm, 20cm, and 30cm) with a common Catphan core. A novel strategy for avoiding cross-scatter in dual-CBCT was developed that utilized interleaved data acquisition on each imaging chain. Contrast and contrast-to-noise-ratio were measured in reconstructions to evaluate the effectiveness of this strategy to avoid the effects of cross scatter.</p><p>A novel correction strategy for cross scatter was developed wherein the cross scatter was regularly sampled during the course of data acquisition and these samples were used as the basis for low- and high- frequency corrections for the cross-scatter in projections. The cross scatter sampling interval was determined for an anthropomorphic phantom at three different sites relevant to radiation therapy by estimating the angular Nyquist frequency. The low frequency portion of the cross scatter distribution is interpolated between samples to provide an estimate of the cross scatter distribution at every projection angle and was then subtracted from the projections.</p><p>The high-frequency portion of the correction was applied after the low-frequency correction was applied. The novel high-frequency correction utilizes the fact that a direct estimate of the high-frequency components was obtained in the cross scatter samples. The high-frequency components of the measured cross scatter were subtracted from the projections in the Fourier domain, a process referred to as spectral subtraction. Each projection is corrected using the cross scatter sample taken at the closest projection angle. In order to apply this correction in the Fourier domain the high-frequency component of the cross scatter must be approximately stationary. To improve the stationarity of the high-frequency cross scatter component a novel two-dimensional, overlapping window was developed. The spectral subtraction was then applied in each window and the results added to form the final image.</p><p>The effectiveness of the correction techniques were evaluated by measuring the contrast and contrast-to-noise-ratio in an image quality phantom. Additionally, the effect of the high-frequency correction on resolution was measured using a line pair phantom.</p><p>Cross scatter in dual CBCT was shown for large phantoms to be much higher than forward scatter which has long been known to be one of the largest degrading factors of image quality in CBCT. This results in large losses of contrast and CNR in reconstructed images. The interleaving strategy for avoiding cross scatter during projection acquisition showed similar performance to cross scatter free acquisitions, however, does not acquire projections at the maximum possible rate. For those applications in which maximizing the acquisition rate of projections is important, the low- and high-frequency corrections effectively mitigated the effects of cross scatter in the dual CBCT system.</p> / Dissertation

This thesis demonstrates the feasibility of methods developed to increase the quality of the crescent bond together with the tail bond quality. Low pull force of the crescent bond limits the usage of insulated Au wire in microelectronics assembly. Premature break of the tail which results in the stoppage of the bonding machine is one of obstacles to overcome for Cu wire. The primary focus of this thesis is to understand the tail and crescent bonding process and then to propose methodologies to improve thermosonic wire bonding processes when Cu and insulated Au wires are used. Several series of experiments to investigate the crescent and tail bonding processes are performed on auto bonders. Cu and insulated Au wires with diameters of 25mm are bonded on the diepads of Ag leadframes. For simplicity, wire loops are oriented perpendicular to the ultrasonic direction. It was found that the crescent bond breaking force by pulling the wire loop (pull force) with insulated Au wire is about 80 % of that of bare Au wire. A modification of the crescent bonding process is made to increase the pull force with insulated Au wire. In the modified process, an insulation layer removing stage (cleaning stage) is inserted before the bonding stage. The cleaning stage consists of a scratching motion (shift) toward to the ball bond in combination with ultrasound. Bonds are then made on the fresh diepad with the insulation removed from the contact surface of the insulated Au wire. This process increases the pull force of the crescent bond up to 26% which makes it comparable to the results obtained with bare Au wire. An online tail breaking force measurement method is developed with a proximity sensor between wire clamp and horn. Detailed understanding of tail bond formation is achieved by studying tail bond imprints with scanning electron microscopy and energy dispersive x-ray analysis. Descriptions are given of the dependence of the tail breaking force on the bonding parameters, metallization variation, and cleanliness of the bond pad. Simultaneous optimization with pull force and tail breaking force can optimize the Cu wire bonding process both with high quality and robustness. It is recommended to first carry out conventional pull force optimization followed by a minimization of the bonding force parameter to the lowest value still fulfilling the pull force cpk requirement. The tail bond forms not only under the capillary chamfer, but also under the capillary hole. The tail breaking force includes both the interfacial bond breaking strength and the breaking strength of the thinned portion of the wire that will remain at the substrate as residue. Close investigations of the tail bond imprint with scanning electron microscopy indicate the presence of fractures of the substrate indicating substrate material being picked up by Cu wire tail. Pick up is found on Au and Cu wires, but the amount of pick up is much larger on Cu wire. The effect on the hardness of the subsequently formed Cu free air ball (FAB) as investigated with scanning electron microscopy and micro - hardness test shows that Cu FABs containing Au and Ag pick ups are softer than those without pick up. However, the hardness varies significantly more with Au pick up. The amount of Au pick up is estimated higher than 0.03 % of the subsequently formed FAB volume, exceeding typical impurity and dopant concentrations (0.01 %) added during manufacturing of the wire.

This thesis demonstrates the feasibility of methods developed to increase the quality of the crescent bond together with the tail bond quality. Low pull force of the crescent bond limits the usage of insulated Au wire in microelectronics assembly. Premature break of the tail which results in the stoppage of the bonding machine is one of obstacles to overcome for Cu wire. The primary focus of this thesis is to understand the tail and crescent bonding process and then to propose methodologies to improve thermosonic wire bonding processes when Cu and insulated Au wires are used. Several series of experiments to investigate the crescent and tail bonding processes are performed on auto bonders. Cu and insulated Au wires with diameters of 25mm are bonded on the diepads of Ag leadframes. For simplicity, wire loops are oriented perpendicular to the ultrasonic direction. It was found that the crescent bond breaking force by pulling the wire loop (pull force) with insulated Au wire is about 80 % of that of bare Au wire. A modification of the crescent bonding process is made to increase the pull force with insulated Au wire. In the modified process, an insulation layer removing stage (cleaning stage) is inserted before the bonding stage. The cleaning stage consists of a scratching motion (shift) toward to the ball bond in combination with ultrasound. Bonds are then made on the fresh diepad with the insulation removed from the contact surface of the insulated Au wire. This process increases the pull force of the crescent bond up to 26% which makes it comparable to the results obtained with bare Au wire. An online tail breaking force measurement method is developed with a proximity sensor between wire clamp and horn. Detailed understanding of tail bond formation is achieved by studying tail bond imprints with scanning electron microscopy and energy dispersive x-ray analysis. Descriptions are given of the dependence of the tail breaking force on the bonding parameters, metallization variation, and cleanliness of the bond pad. Simultaneous optimization with pull force and tail breaking force can optimize the Cu wire bonding process both with high quality and robustness. It is recommended to first carry out conventional pull force optimization followed by a minimization of the bonding force parameter to the lowest value still fulfilling the pull force cpk requirement. The tail bond forms not only under the capillary chamfer, but also under the capillary hole. The tail breaking force includes both the interfacial bond breaking strength and the breaking strength of the thinned portion of the wire that will remain at the substrate as residue. Close investigations of the tail bond imprint with scanning electron microscopy indicate the presence of fractures of the substrate indicating substrate material being picked up by Cu wire tail. Pick up is found on Au and Cu wires, but the amount of pick up is much larger on Cu wire. The effect on the hardness of the subsequently formed Cu free air ball (FAB) as investigated with scanning electron microscopy and micro - hardness test shows that Cu FABs containing Au and Ag pick ups are softer than those without pick up. However, the hardness varies significantly more with Au pick up. The amount of Au pick up is estimated higher than 0.03 % of the subsequently formed FAB volume, exceeding typical impurity and dopant concentrations (0.01 %) added during manufacturing of the wire.