Yes / Wavelets are alternative building kernels of the multicarrier systems, such as the orthogonal frequency division multiplexing (OFDM). The wavelets can be designed by changing the parent basis functions or constructing new filters. Some two new wavelets are considered for multicarrier design; one is designed using raised-cosine functions while the other was constructed using ideal filters. The spectrums of raised cosine wavelet filters are controlled by a roll-off factor which leads to many distorting sidelobes. The second family of wavelet, which the raised-cosine wavelet is compared to, have no distorting sidelobes. It will be shown that raised-cosine wavelets are less suitable for multicarrier design in multicarrier environment, in terms of BER when compared to the wavelet constructed from the ideal filter.

Abstract In this thesis, we have fabricated a novel poly-Si thin film transistor with self-aligned SiGe raised source/drain (SiGe-RSD TFT). The SiGe-RSD regions were grown selectively by ultra-high vacuum chemical vapor deposition (UHVCVD) at 550¢J. The resultant transistor structure features a thin active channel region and a self-aligned thick source/drain region, which is ideally suited for optimum performance. A significant improvement on the turn-on current in the transfer characteristics is observed, compared to the conventional TFT counterpart. While the conventional TFT depicts severe resistance-limited output characteristics, especially at high gate bias, due to large source and drain series resistance. The new device, in contrast, exhibits excellent output characteristics. Finally, with comparable leakage current in both structures, the on/off current ratio is approximately 2 order of magnitudes higher in the proposed SiGe-RSD TFTS

The objective of the research reported in this thesis was to elucidate the mode of disappearance of the last ice-sheet to cover the Loch Long/Loch Fyne area in the SW Highlands, and to establish the sequence of raised shorelines that has been formed as a result of the interplay between eustatic and isostatically-induced sea-level changes consequent upon the melting of the ice. The study was geomorphological in orientation and a methodology was adopted that involved mapping, at a scale of 1:10,560, all glacial, fluvial and marine landforms below approx. 75 - 100 m O.D., and the subsequent accurate instrumental surveying of all relevant landforms. A certain amount of mapping back from the coast was also carried out where relevant. The errors inherent in the methods adopted and in the use of various types of marine landforms were quantitatively assessed and it was concluded that raised shorelines could be reconstructed with an accuracy of ±0.54 m using intertidal deltas and ±0.61 m using marine erosional features. The southern part of the study area was deglaciated first at ca. 13,000 yr BP. The dominant mode of deglaciation was that of rapid retreat in the sea lochs (possibly as much as 500 m/yr) due to calving that left isolated dead-ice masses in various side valleys. This retreat was punctuated by two major periods of stillstand or readvance, the Otter Ferry Stage (ca. 12,900 ± 200 yr BP) and the Loch Lomond Readvance (ca. 11,000 - 10,000 yr BP). Eight raised shorelines have been identified as having formed during the relative fall of sea-level from ca. 38 - 40 m O.D. that accompanied the disappearance of the icesheet. A particularly well developed shoreline, CLG2, was formed during the Otter Ferry Stage. A further unique rock-cut shoreline, the Main Rock Platform, was at least in part formed during the cold conditions immediately prior to and during the Loch Lomond Stadial. During the Loch Lomond Stadial glaciers extended down Loch Long to near Ardentinny and down Loch Fyne to beyond Furnace. The mountains in the NE of the study area stood proud of the ice mass as nunataks whilst a number of small valley glaciers occurred in the S of the Cowal Peninsula. Analysis of shoreline gradients and the sea-level change curve suggests that this build-up of ice was sufficient to depress the earth's crust anew. During the early part of the Flandrian Period a major transgression has been recorded by radiocarbon-dated buried peats. This transgression culminated some time after 7,200 yr BP in the formation of a major raised shoreline (CFl) and during the subsequent regression a further five shorelines were formed.

Yes / New orthogonal wavelet transforms can be designed by changing the wavelet basis functions or by constructing new low-pass filters (LPF). One family of wavelet may appeal, in use, to a particular application than another. In this study, the wavelet transform based on raisedcosine spectrum is used as an independent orthogonal wavelet to study multicarrier modulation behaviour over multipath channel environment. Then, the raised-cosine wavelet is compared with other well-known orthogonal wavelets that are used, also, to build multicarrier modulation systems. Traditional orthogonal wavelets do not have side-lobes, while the raised-cosine wavelets have lots of side-lobes; these characteristics influence the wavelet behaviour. It will be shown that the raised-cosine wavelet transform, as an orthogonal wavelet, does not support the design of multicarrier application well like the existing well-known orthogonal wavelets.

Northern peatlands represent a significant carbon reservoir, containing approximately a third of the terrestrial carbon pool. The stability of these carbon stores is poorly understood, and processes of accumulation and degradation appear to be finely balanced. Over the last decade, it has become increasingly clear that losses of dissolved organic carbon (DOC) from peatlands can be of considerable size and this flux appears to have increased substantially over the last 20 years. Despite its significance, the chemical composition of peatland-derived DOC remains poorly understood. This study aimed to characterise dissolved organic matter (DOM) at the molecular level using a novel combination of techniques. The study site (Cors Fochno, Wales, UK) is an ombrotrophic bog on which a number of studies into carbon cycling and hydrology have been carried out, providing a useful context for this project. The size and compositions of the DOC pool was monitored over 18 months, from three banks of piezometers, sampling from depths of 15 cm to 6 m. DOM which is representative of bog runoff was also monitored. DOC concentrations varied considerably between locations, spanning an order of magnitude (11.4 to 114 mgC l-1). Several relationships between DOC concentration and environmental and physical factors were established: DOC levels near the surface of the peatland varied with temperature, those in the runoff were most affected by recent rainfall events and the apparent DOC concentration at depth was related to the hydraulic conductivity of peat at that depth. The annual flux of DOC from the site was estimated at 113 tonnes, or 17.4 gC m-2. Only a small portion of the DOC pool could be characterised by analysis of dissolved combined amino acids (DCAA) and dissolved carbohydrates (as neutral sugars). Non-protein amino acids were most abundant in runoff samples, suggesting microbial reworking of DOM on entering drainage systems. DCAA yields decreased with depth, and the DCAA pool in deeper peat layers was characterised by more hydrophobic compounds. Interpretation of semi-quantitative results from TMAH thermochemolysis GC-MS analysis suggested oxidative degradation of organic matter near the surface of the peatland and photochemical degradation where DOM entered drainage networks, and this was supported by novel interpretation of results from ultrahigh resolution mass spectrometry analysis. The deepest porewaters were dominated by nalkanes, with notable contributions from fatty acids, suggesting a plant wax source for this DOM. The highest DOC concentrations were found at intermediate depth from a site midway between the centre of the bog and the southern boundary where hydraulic conductivities were low, and DOM from these piezometers were characterised by high contributions from a suite of phenolic compounds (with mainly para-hydroxyphenyl structures). These compounds have been linked to Sphagnum species, and are known to be functionally important to the development and maintenance of the unusual chemical environment in peatlands which slows decay rates, reduces microbial activity, and allows the sequestration of the large carbon reservoir. The findings of this study highlight the dynamic nature of peatland derived DOM, both in the size of the carbon pool and its composition which change dramatically with both season and depth.

Although there have been many studies focusing on Asian Americans’ ethnic identity and the stereotypes associated with them, little is known about how Asian Americans negotiate their multiple layers of ethnic identity and respond to the stereotypes imposed on them. The main goals of the current study were to examine American-Raised Chinese’ (i.e., Chinese who were born and/or raised in America) multiple layers of ethnic identity and their negotiation process of these multiple layers of ethnic identity, the relationship between their ethnic identity and stereotypes, and the creative ways American-Raised Chinese interpreted and responded to stereotypes. Another goal of this study was to examine the role of an ethnic student organization on campus and American-Raised Chinese’s participation in the organization. Through Chinese Cultural Association, I interviewed eighteen informants and observed their daily practices in public and private settings. The findings indicated that American-Raised Chinese undergraduates choosing to participate in an ethnic student organization over other organizations reflected their active negotiation of the multilayered ethnic identity. In addition, by meeting Chinese of different nationalities on campus and abroad, these undergraduates came to realize the diverse background of Chinese individuals, leading them to reexamine and reconstruct their ethnic identity. In particular, these undergraduates developed diasporic Chinese identity that not only acknowledged the diversity of Chinese community in America in terms of nationality, but also transformed their American identity into “ethnic” identity among Chinese of different nationalities. The findings also showed that American-Raised Chinese’ negotiation of their ethnic identity was closely related to their perception of the stereotypes. The informants came to recognize the changing nature of stereotypes and this realization led them to reconstrue their understanding of ethnic identity. Furthermore, using anecdotes of American-Raised Chinese undergraduates’ self impersonation, I argued that these undergraduates proactively responded to the stereotypes by making parody about themselves. Through self impersonation, these undergraduates achieved the double intents of performing themselves as Asian American and simultaneously challenged what the dominant American society expected them to be. / text

Recent research has shown that traditional safety evaluation methods have been inadequate in accurately determining the effectiveness of roadway safety measures. In recent years, advanced statistical methods have been utilized in traffic safety studies to more accurately determine the effectiveness of roadway safety measures. These methods, particularly hierarchical Bayesian statistical techniques, have the capabilities to account for the shortcomings of traditional methods. Hierarchical Bayesian modeling is a powerful tool for expressing rich statistical models that more fully reflect a given problem than a simpler model could. This paper uses a hierarchical Bayesian model to analyze the effectiveness of two types of road safety measures: raised medians and cable barriers. Several sites where these safety measures have been implemented in the last 10 years were evaluated using available crash data. This study analyzes the effectiveness of raised medians and cable barriers of roadway safety by determining the effect each has on crash frequency and severity at selected locations. The results of this study show that the installation of a raised median is an effective technique to reduce the overall crash frequency and severity on Utah roadways. The analysis of cable barriers showed that cable barriers were effective in decreasing cross-median crashes and crash severity.

Throughout Amazonia, earthworks are found in areas of diverse linguistic and ethnic backgrounds. The distribution of these earthworks within various linguistic and ethnic areas suggests a multiethnic or multilinguistic network, in which interaction between these diverse groups occurred, creating diverse communities. Movement and communication within Amazonia along river networks allowed for this interaction. Interaction between groups in Amazonia may have also influenced the different methods of landscape modification. This thesis presents a GIS-based spatial analysis of raised fields, a type of agricultural earthwork found throughout the Llanos de Mojos (Mojos), located in the Beni Department of Bolivia. The distribution of fields, forest islands, and rivers was analyzed to distinguish the relationship between these features in the study area. The spatial analysis distinguished patterns between raised fields found along two sets of rivers, the Iruyañez and Omi Rivers, and the Yacuma and Rapulo Rivers. Spatial patterns found within these distributions were also compared to the distribution of linguistic groups in the area. Among these patterns, it is seen that one kind of agricultural earthwork is found in areas associated with different linguistic groups. The spatial patterns found among the raised fields and forest islands in relation to the linguistic groups in the area demonstrate the fluidity between groups in the region. Insight to movement and communication in Mojos can be understood through the interaction between linguistic groups and the distribution of archaeological features in the region.

No / A proxy climate record from a raised bog in County Fermanagh, Northern Ireland, is presented. The record spans the interval between 2850 cal. yr BC and cal. yr AD 1000 and chronological control is achieved through the use of tephrochronology and 14C dating, including a wiggle-match on one section of the record. Palaeoclimatic inferences are based on a combination of a testate amoebae-derived water table reconstruction, peat humification and plant macrofossil analyses. This multiproxy approach enables proxy-specific effects to be identified. Major wet shifts are registered in the proxies at ca. 1510 cal. yr BC, 750 cal. yr BC and cal. yr AD 470. Smaller magnitude shifts to wetter conditions are also recorded at ca. 380 cal. yr BC, 150 cal. yr BC, cal. yr AD 180, and cal. yr AD 690. It is hypothesised that the wet shifts are not merely local events as they appear to be linked to wider climate deteriorations in northwest Europe. Harmonic analysis of the proxies illustrates statistically significant periodicities of 580, 423-373, 307 and 265 years that may be related to wider Holocene climate cycles. This paper illustrates how the timing of climate changes registered in peat profiles records can be precisely constrained using tephrochronology to examine possible climatic responses to solar forcing. Relying on interpolated chronologies with considerable dating uncertainty must be avoided if the climatic responses to forcing mechanisms are to be fully understood.

Modern agricultural systems have been criticized for their detrimental effects on the environment and a general emphasis on crop yield rather than long-term sustainability. Traditional forms of agriculture may provide case-specific examples of sustainable alternatives for contemporary societies. In the seasonally inundated savannas of the Llanos de Mojos, pre-Columbian Indians piled earth into ‘large raised field platforms’ elevated high enough above the floodplain to allow crops to grow. Archaeological evidence indicates that raised field agriculture supported much larger populations than those found in the Beni today. The examination of satellite imagery has revealed more than 40,000 individual fields spread across an area of approximately 7,500 square kilometers. This study created a digitized map of large raised fields to search for spatial patterns in their distribution. A GIS analysis was conducted in which fields were distributed into organizational groups based on characteristics such as proximity and orientation to cardinal direction. These groups represent potential ‘social units’ involved in the organization of labor required to construct raised fields. This study demonstrated the consistent presence of these units throughout the entirety of the agricultural system. Patterns in the distribution of these groups allowed the study area to be divided into two distinct regions representing a larger scale of organization within a seemingly uniform system. A transitional zone between these two regions was identified on the river Omi, providing a clear area of interest to target in future archaeological excavations. Further archaeological investigations of raised field agriculture have the potential of demonstrating the overall productivity of the system as well as how it was incorporated into the social systems of those who managed it.