Peoples pay more and more attention on document clustering methods. Because of the high dimension and the large number of data, clustering methods usually need a lot of time to calculate. We propose a scheme to make the clustering algorithm much faster then original. We partition the whole dataset to several parts. First, use one of these parts for clustering. Then according to the label after clustering, we reduce the number of features by a certain ratio. Add another part of data, convert these data to lower dimension and cluster them again. Repeat this until all partitions are used. According to the experimental result, this scheme may run twice faster then the original clustering method.

The present study explores the concepts behind Japanese and Swedish dimensional adjectives. The focus is on examining which similarities and differences in the conceptualisation across the two languages exist, if any at all. In order to see how concepts underlying dimensional adjectives are represented in the speaker's minds, data was collected mainly from two word-association tests. The results show that dimensional adjectives are conceptualised and represented differently by speakers of these two languages. The most remarkable difference resulting from the word-association tests is that Japanese participants associate dimensional adjectives mostly with nouns that denote entities the prominent extension of which is aptly described by the stimulus dimensional adjective (e.g. 'long' is associated with 'river'). In Swedish, however, participants associate dimensional adjectives with both adjectives and nouns, and the association patterns and their underlying conceptualisations are thus more diverse (e.g. 'high' is associated with 'building', and 'long' is associated with 'narrow').

<p>This dissertation presents the first experiments on radio frequency (rf) spectroscopy of a quasi-two dimensional strongly interacting ultracold atomic Fermi gas. A 50-50 mixture of spin-up and spin-down atoms is confined in a series of pancake-shaped traps produced using an optical standing-wave. To make the system quasi-two dimensional, I adjust the Fermi energy in the weakly confined direction to be comparable to the harmonic oscillator energy level spacing in the tightly confined direction.</p><p>For a perfectly two dimensional system, at low enough temperature, spin-up and spin-down atoms should form dimers in the ground state of the tightly confined direction. However, in our quasi-two dimensional system I find that the simple dimer theory does not agree with the measured radio-frequency spectra. Instead, the data can be explained by polaron to polaron transitions, which is a many-body effect. Here, a polaron is a spin-down impurity surrounded by a cloud of particle-hole pairs in a spin-up Fermi sea. With this unique strongly interacting quasi-two dimensional system, I am able to study the interplay between confinement induced two-body pairing and many-body physics in confined mesoscopic systems of several hundred atoms, which has not been previously explored and offers new challenges for predictions.</p> / Dissertation

This paper presents methods for photo-realistic rendering using strongly spatially variant illumination captured from real scenes. The illumination is captured along arbitrary paths in space using a high dynamic range, HDR, video camera system with position tracking. Light samples are rearranged into 4-D incident light fields (ILF) suitable for direct use as illumination in renderings. Analysis of the captured data allows for estimation of the shape, position and spatial and angular properties of light sources in the scene. The estimated light sources can be extracted from the large 4D data set and handled separately to render scenes more efficiently and with higher quality. The ILF lighting can also be edited for detailed artistic control.

Salmonella species continue to be commonly associated with cases of food-borne disease in developed countries. In the United States in 2001, the incidence per 100,000 people was highest for salmonellosis (15.1), followed by campylobacteriosis (13.8) and shigellosis (6.4). Enteric pathogens usually contaminate the surface of raw animal products during slaughter and primary processing (scalding, defeathering or dehiding, rinsing, cutting, mixing, and grinding, etc.) and can attach and/or reside in the regular and irregular surfaces of the skin, multiply and, thereafter, contaminate food preparation surfaces, hands and utensils. Trisodium phosphate (TSP) has been approved by the USDA as a sanitizer to reduce surface loads of Salmonella on chicken carcasses. A number of studies had demonstrated that TSP effectively removes surface contamination of carcasses by food-borne pathogens. However, very little scientific evidence is available which identifies the actual mechanisms of TSP antimicrobial activity and the response of food-borne pathogens exposed to TSP. This study examined both the physiological and molecular response of Salmonella enterica serovar Enteritidis to TSP treatment. The role of high pH during TSP treatment on its antimicrobial activity was examined. Adaptation of S. enterica serovar Enteritidis to TSP treatment was also examined by analyzing the proteome of serovar Enteritidis cells using two-dimensional gel electrophoresis and mass spectrometry. The role of high pH on the antimicrobial activity of TSP was examined using comparative studies involving treatment solutions containing different concentrations of TSP, treatment solutions adjusted to the equivalent pH as in each of the TSP treatments and TSP solutions pH adjusted to 7.0. Direct and indirect indices of cell survival, membrane damage, and cellular leakage were also employed to examine specific antimicrobial effects. Cell viability, loss of membrane integrity, cellular leakage, release of lipopolysaccharides and cell morphology were accordingly examined and quantified under the above treatment conditions. Exposure of serovar Enteritidis cells to TSP or equivalent alkaline pH made with NaOH resulted in the loss of cell viability and membrane integrity in a TSP concentration- or NaOH-alkaline pH-dependent manner. In contrast, cells treated with different concentrations of TSP whose pH was adjusted to 7.0 did not show any loss of cell viability or membrane integrity. These results indicate that TSP is a potent membrane-acting agent, and provide compelling evidence that high pH during TSP treatment was responsible for its antimicrobial activity. Adaptation of S. enterica serovar Enteritidis with a sublethal concentration of TSP resulted in the induction of the alkaline stress response. Alkaline stress response involves induced thermotolerance, resistance to higher concentrations of TSP, high pH and sensitivity to acid. Examination of the proteome of TSP-adapted cells revealed differential expression of a number of proteins but did not include the common heat shock proteins involved in thermotolerance. However, TSP adaptation caused a shift in the membrane fatty acid composition from unsaturated to a higher saturated and cyclic fatty acid. This shift in fatty acid composition increases the melting point of the cytoplasmic membrane so that it remains functional at high temperatures. Biofilm bacteria are more resistant to sanitizers, heat and antimicrobial agents than their planktonic counterparts. Examination of the proteome of TSP-adapted biofilm cell of S. enterica serovar Enteritidis revealed little overlap in the protein profile compared to TSP-adapted planktonic cells. Proteomic examination of planktonic and biofilm cells of S. enterica serovar Enteritidis revealed differential expression of a number of proteins involved in DNA replication, stress survival and transport of newly synthesized proteins. These results clearly indicate that changes in the expression of specific genes are involved in the biofilm mode of growth, which could play a significant role in resistance to antimicrobial agents. The results of the current study provide a better understanding of the mechanisms of antimicrobial action of TSP and also elucidate the response of S. enterica serovar Enteritidis to TSP and high pH adaptation. The study also raises new questions regarding stress tolerance of S. Enteritidis following TSP or alkaline pH adaptation with relevance to food safety.

Salmonella species continue to be commonly associated with cases of food-borne disease in developed countries. In the United States in 2001, the incidence per 100,000 people was highest for salmonellosis (15.1), followed by campylobacteriosis (13.8) and shigellosis (6.4). Enteric pathogens usually contaminate the surface of raw animal products during slaughter and primary processing (scalding, defeathering or dehiding, rinsing, cutting, mixing, and grinding, etc.) and can attach and/or reside in the regular and irregular surfaces of the skin, multiply and, thereafter, contaminate food preparation surfaces, hands and utensils. Trisodium phosphate (TSP) has been approved by the USDA as a sanitizer to reduce surface loads of Salmonella on chicken carcasses. A number of studies had demonstrated that TSP effectively removes surface contamination of carcasses by food-borne pathogens. However, very little scientific evidence is available which identifies the actual mechanisms of TSP antimicrobial activity and the response of food-borne pathogens exposed to TSP. This study examined both the physiological and molecular response of Salmonella enterica serovar Enteritidis to TSP treatment. The role of high pH during TSP treatment on its antimicrobial activity was examined. Adaptation of S. enterica serovar Enteritidis to TSP treatment was also examined by analyzing the proteome of serovar Enteritidis cells using two-dimensional gel electrophoresis and mass spectrometry. The role of high pH on the antimicrobial activity of TSP was examined using comparative studies involving treatment solutions containing different concentrations of TSP, treatment solutions adjusted to the equivalent pH as in each of the TSP treatments and TSP solutions pH adjusted to 7.0. Direct and indirect indices of cell survival, membrane damage, and cellular leakage were also employed to examine specific antimicrobial effects. Cell viability, loss of membrane integrity, cellular leakage, release of lipopolysaccharides and cell morphology were accordingly examined and quantified under the above treatment conditions. Exposure of serovar Enteritidis cells to TSP or equivalent alkaline pH made with NaOH resulted in the loss of cell viability and membrane integrity in a TSP concentration- or NaOH-alkaline pH-dependent manner. In contrast, cells treated with different concentrations of TSP whose pH was adjusted to 7.0 did not show any loss of cell viability or membrane integrity. These results indicate that TSP is a potent membrane-acting agent, and provide compelling evidence that high pH during TSP treatment was responsible for its antimicrobial activity. Adaptation of S. enterica serovar Enteritidis with a sublethal concentration of TSP resulted in the induction of the alkaline stress response. Alkaline stress response involves induced thermotolerance, resistance to higher concentrations of TSP, high pH and sensitivity to acid. Examination of the proteome of TSP-adapted cells revealed differential expression of a number of proteins but did not include the common heat shock proteins involved in thermotolerance. However, TSP adaptation caused a shift in the membrane fatty acid composition from unsaturated to a higher saturated and cyclic fatty acid. This shift in fatty acid composition increases the melting point of the cytoplasmic membrane so that it remains functional at high temperatures. Biofilm bacteria are more resistant to sanitizers, heat and antimicrobial agents than their planktonic counterparts. Examination of the proteome of TSP-adapted biofilm cell of S. enterica serovar Enteritidis revealed little overlap in the protein profile compared to TSP-adapted planktonic cells. Proteomic examination of planktonic and biofilm cells of S. enterica serovar Enteritidis revealed differential expression of a number of proteins involved in DNA replication, stress survival and transport of newly synthesized proteins. These results clearly indicate that changes in the expression of specific genes are involved in the biofilm mode of growth, which could play a significant role in resistance to antimicrobial agents. The results of the current study provide a better understanding of the mechanisms of antimicrobial action of TSP and also elucidate the response of S. enterica serovar Enteritidis to TSP and high pH adaptation. The study also raises new questions regarding stress tolerance of S. Enteritidis following TSP or alkaline pH adaptation with relevance to food safety.

A numerical analysis is performed for the three-dimensional, turbulent flow of air in a thyristor valve hall located at the Dorsey Converter Station, owned and operated by Manitoba Hydro. The goal of this analysis was to determine the configurations that result in increased air-side cooling effectiveness in the valve hall. The governing equations are solved using the Computational Fluid Dynamics (CFD) code CFX-5. This computer code uses a finite volume method of solution and is based on a finite element approach for representing the geometry. The effects of inlet and outlet opening geometry, inlet air mass flow rate, and inlet air angle on the thermal performance for the air-side cooling of the thyristor valve hall geometry are examined. / May 2006

No description available.

The biggest limitation to conventional gas chromatography (GC) is limited peak capacity, making the analysis of complex mixtures a difficult or even impossible task. Comprehensive two-dimensional gas chromatography (GC×GC) significantly increases peak capacity and resolution, improves sensitivity and generates structured 3D chromatograms. This is achieved by connecting two columns coated with different stationary phases through a special interface (modulator). The interface samples the first column effluent and periodically injects fractions of this material, as narrow injection pulses, onto the second column for further separation. Commercial instruments achieve this with cryogenic agents. Since this expensive approach permits only in-laboratory analysis, the development of simple, economical and field-capable GC×GC systems is in demand. This report summarizes the fundamentals governing GC×GC separations and a brief history of technological advances in the field. It also documents the construction of a simple interface, devoid of moving parts and cryogenic consumables, and hence highly suitable for field analysis and monitoring applications. Evaluation of the interface suggests on-par performance with more complicated cryogenic modulators. GC×GC separations of technical mixtures of fatty acid methyl esters (FAMEs), common environmental pollutants (EPA 8270), polychlorinated biphenyls (PCBs), pesticides (toxaphene), as well as selected essential oils and major distillation fractions of crude oil indicate very good performance. Most notably, the interface prototype was applied for the first ever time-resolved on-site analysis of the semivolatile organic fraction of urban air particulate matter (PM2.5).

This thesis explores the multi-dimensional aspects of space by engaging three primary “modes of knowing”: the corporeal, the virtual and the spiritual. The crossings of these modes are investigated through the development of three characters in a film; Kira is the earth-worshipping goddess; Kisho is the cyborg, a permanently uploaded information-seeker; and the Shaman is a shape-shifting lightworker. These characters evolve from the distillation of specific readings related to each of the aforementioned modes as well as from interviews and experiences that assist in their development. These readings range from Novalis and Ashley Montagu on corporeal knowledge, Donna Harraway and Neil Spiller on technologically enhanced trans-human states and Fritjof Capra and Alex Grey on the intersection of ancient mystical teaching with recent findings in quantum physics. This exploration is followed by the design portion of the thesis: a short film where each character occupies a separate world in the dystopian future. The radical and regenerative possibilities of their crossings are what the film initiates.