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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Diagnostic studies of mid-latitude depressions

Golding, B. W. January 1981 (has links)
No description available.
2

Development of a prediction model for bacteremia in hospitalized adults with cellulitis to aid in the efficient use of blood cultures: a retrospective cohort study

Lee, Chun-Yuan, Kunin, Calvin M., Chang, Chung, Lee, Susan Shin-Jung, Chen, Yao-Shen, Tsai, Hung-Chin 19 October 2016 (has links)
Background: Cellulitis is a common infectious disease. Although blood culture is frequently used in the diagnosis and subsequent treatment of cellulitis, it is a contentious diagnostic test. To help clinicians determine which patients should undergo blood culture for the management of cellulitis, a diagnostic scoring system referred to as the Bacteremia Score of Cellulitis was developed. Methods: Univariable and multivariable logistic regression analyses were performed as part of a retrospective cohort study of all adults diagnosed with cellulitis in a tertiary teaching hospital in Taiwan in 2013. Patients who underwent blood culture were used to develop a diagnostic prediction model where the main outcome measures were true bacteremia in cellulitis cases. Area under the receiver operating characteristics curve (AUC) was used to demonstrate the predictive power of the model, and bootstrapping was then used to validate the performance. Results: Three hundred fifty one cases with cellulitis who underwent blood culture were enrolled. The overall prevalence of true bacteremia was 33/351 cases (9.4 %). Multivariable logistic regression analysis showed optimal diagnostic discrimination for the combination of age >= 65 years (odds ratio [OR] = 3.9; 95 % confidence interval (CI), 1.5-10.1), involvement of non-lower extremities (OR = 4.0; 95 % CI, 1.5-10.6), liver cirrhosis (OR = 6.8; 95 % CI, 1.8-25.3), and systemic inflammatory response syndrome (SIRS) (OR = 15.2; 95 % CI, 4.8-48.0). These four independent factors were included in the initial formula, and the AUC for this combination of factors was 0.867 (95 % CI, 0.806-0.928). The rounded formula was 1 x (age >= 65 years) + 1.5 x (involvement of non-lower extremities) + 2 x (liver cirrhosis) + 2.5 x (SIRS). The overall prevalence of true bacteremia (9.4 %) in this study could be lowered to 1.0 % (low risk group, score <= 1.5) or raised to 14.7 % (medium risk group, score 2-3.5) and 41.2 % (high risk group, score >= 4.0), depending on different clinical scores. Conclusions: Determining the risk of bacteremia in patients with cellulitis will allow a more efficient use of blood cultures in the diagnosis and treatment of this condition. External validation of this preliminary scoring system in future trials is needed to optimize the test.
3

Snow avalanches in Scotland, with particular reference to the Cairngorm Mountains

Ward, Rodney G. W. January 1981 (has links)
The thesis describes a method for predicting avalanche activity in Scotland, based primarily on meteorological and topographical data, and this is incorporated into a framework for avalanche forecasting. A literature review identifies the main meteorological and topographical factors causing avalanche release. Snow accumulation, cold temperatures or thaws are identified as the major meteorological factors causing avalanches, and the thesis so distinguishes two basic avalanche types---the direct-action avalanche caused by fresh snow accumulation, and the climax avalanche caused by temperature changes. Slope angle, surface roughness, slope geometry and catchment area are identified as the major topographical controls on the location of avalanche activity. The thesis presents data on avalanche activity in Scotland over the last two hundred and eighty years, with particular emphasis on the Cairngorm Mountains. Avalanche locations, types and magnitudes for almost a thousand avalanches are described. Data on Scottish weather and terrain conditions are also presented, also with particular emphasis on the Cairngorm area. Major periods of snow accumulation, cold temperatures and thaws are identified between the winters of 1977/78 and 1979/80, and the location of steep slopes, smooth surfaces and large catchment areas in the Cairngorms is described. Data on the characteristics of the Scottish snow cover, based on work performed in the Cairngorms by E. Langmuir, B. Beattie and the author are then presented. Correlations between avalanche activity and meteorological, topographical and glaciological conditions are demonstrated, and this enables a predictive model to be developed which assesses avalanche probability on the basis of the amount of fresh snowfall and the prevailing temperature. Fresh snowfall of 200 mm., and either several days of cold weather with maximum temperatures below -4&deg;C or two or three days of warm weather with maximum temperatures above 0&deg;C lead to avalanche activity. The model can be continually up-dated and permits a continuous avalanche probability assessment to be made.
4

Proposed llfe prediction model for an automotive wheel

McGrath, PJ 01 January 2004 (has links)
Summary Historicully, stress analysis used for component design assames "ideal" materials, i.e. with isotropic, homogeneous and uniform metallurgical properties. We know that this is untrue, no matter how good the design. As design cannot provide fo, defect-free materials or components, ok appropriute defect tolerance should be the aim of the designer. Hence the concept of fuil-safe components has been introduced fo, safety-critical purts. Automotive wheels, howeveF, ure not considered fail-safe and fatigue lW prediction techniques fo, these components need to be improved in an endeavour to provide light-weight, attractive, but still safe und durable wheels. This applied approuch, where the proposed lW prediction model employs relutionships given by Gerber und a proposed lW prediction model derived from combining aspects of lW prediction models according to Collins und Juvinall & Marshek. The results show good coruelation with that of uctual wheel fatigue data.
5

The effects of load interaction on fatigue crack growth and crack closure in aluminium alloys

McMaster, Fraser J. January 1998 (has links)
No description available.
6

Variation and prediction of assimilable organic matters in a water treatment process and the distribution system

Chen, Po-feng 04 July 2010 (has links)
The growth of the heterotrophic plate count in distribution system, causing deterioration of drinking water quality, is called biological re-growth or after-growth. There are many methods to solve above problems such as disinfecting and washing in pipeline. Among them, to lower the concentration of assimilable organic carbon(AOC) in drinking water under a certain level is showed the best control method for inhibiting the growth of microorganisms. AOC is showed as an item of the organic amounts by using microorganisms. The samples of water after disinfecting is took into bacterial of P17 and NOX. Then we measure the growth number counts of two kind of bacterial in their plate to transfer and obtain the concentration of AOC. In this study we investigate the variation of AOC in a tradition water treatment plant and its distribution system by using the results of sampling and analysis of the related items of water quality. Results showed the proportional of AOC-P17 was highest in contains of AOC. The removal of AOC during processes of water treatment was effectively found. But the pre-chlorination caused the increase of AOC level in water let the concentration of AOC be detected over 50£gg acetate-C/L in treated water and the distribution system. AOC level decreased with the increasing distance of distribution system. For the well relation with drinking water quality and treatment units, we should control the biological stability to obtain a good water quality of treated water. Finally we analysis 13 items of water quality by using AutoNet(6.03) with AOC to do the prediction model work. After data simulation and training analysis, three models of AOC prediction (denoted as WTP, Distribution system and WTP& Distribution system) were obtained. The comparisons of three models in inner and outer verification showed good correlation results as well.
7

Epidemiological aspects of Claviceps africana, causal agent of Sorghum ergot

Noe, Montes Garcia, Noe, Montes Garcia 17 February 2005 (has links)
Sorghum ergot, caused by Claviceps africana Frederickson, Mantle & de Milliano, is a disease that affects non-fertilized ovaries in sorghum male-sterile plants and infects hybrids if there is pollen sterility at flowering time. Sphacelia containing macroconidia could play a role in the survival of the pathogen. This study developed risk assessment models and evaluated environmental conditions affecting viability of macroconidia and transition from sphacelial to sclerotial tissues. Effect of weather on ergot severity was evaluated under natural conditions (in monthly planting dates) in nine sorghum genotypes at College Station, Weslaco, Rio Bravo, and Celaya. Panicles were inoculated daily beginning at flower initiation with a suspension of 1.6 x 106 C. africana conidia ml-1. Weather triad values were used to identify weather parameters correlated with the disease. Ergot severity was statistically greater in A-lines than hybrids because of the possible interference of pollen on some dates. Celaya had the greatest amount of ergot in hybrids. A-line ATx2752 had the lowest average ergot severity throughout years, locations and planting dates, as did the hybrid NC+8R18. Maximum and minimum temperature had a negative correlation with ergot at Rio Bravo, College Station and Weslaco, while at Celaya it was positive. The highest correlation was 7 to 9 days before initiation of flowering, suggesting that cooler temperatures during this period could cause male sterility. A-lines showed the same relationships between ergot and maximum and minimum temperatures after initiation of flowering. Minimum relative humidity had a positive correlation with ergot after initiation of flowering in both sorghum plant types. Sphacelia stored under cool temperatures (-3oC to 7oC) maintained conidial viability, and newly-formed sphacelia located on the sphacelia surface had the highest conidial viability. However, they show a greater viability reduction through time compared with conidia from older sphacelia, showing that conidial maturity can play a role in the survival of the conidia. Sphacelia on plants grown at 10oC, 20oC and 30oC with low relative humidity did not had any sclerotial development up to 4 weeks after formation of sphacelia. However, higher temperatures promoted an increase in the sphacelia dry weight during that time.
8

Settlement characteristics of landfill sites

Green, Damian C. January 2000 (has links)
No description available.
9

Temperature Prediction Model for Horizontal Well with Multiple Fractures in Shale Reservoir

Yoshida, Nozomu 03 October 2013 (has links)
Fracture diagnostics is a key technology for well performance prediction of a horizontal well in a shale reservoir. The combination of multiple fracture diagnostic techniques gives reliable results, and temperature data has potential to provide more reliability on the results. In this work, we show an application of a temperature prediction model for a horizontal well with multiple hydraulic fractures in order to investigate the possibility of evaluating reservoir and hydraulic fracture parameters using temperature data. The model consists of wellbore model and reservoir model. The wellbore model was formulated based on mass, momentum and energy balance. The reservoir flow model was solved by a numerical reservoir simulation, and the reservoir thermal model was formulated by transient energy balance equation considering viscous dissipation heating and temperature variation caused by fluid expansion besides heat conduction and convection. The reservoir flow and reservoir thermal model were coupled with the wellbore model to predict temperature distribution in a horizontal well considering boundary conditions at the contact of reservoir and wellbore. In the reservoir system, primary hydraulic fractures which are transverse to the horizontal well were modeled with thin grid cells explicitly, and the hydraulically-induced fracture network around the horizontal well was modeled as higher permeable zone to unstimulated matrix zone. The reservoir grids between two primary fractures were logarithmically spaced in order to capture transient flow behavior. We applied the model to synthetic examples: horizontal well with identical five fractures and with different five fractures. The results show two fundamental mechanisms: heat conduction between formation and wellbore fluid at non-perforated zone, and wellbore fluid mixing effect at each fracture. The synthetic example with identical fractures shows that fracture locations affect wellbore temperature distribution because of fluid mixing effect between reservoir inflow and wellbore fluid. And also, the synthetic example with different fractures shows that the fracture heterogeneity causes different magnitude of temperature change due to inflow variation per fracture. In addition, the model was applied to synthetic examples without network fracture region in order to find the effects by the network. It reveals that under constant rate condition, network fracture masks large temperature change due to small pressure change at the contact between fracture and formation, and that under constant BHP condition, network fracture augments temperature change with the increase of flow rate in wellbore and inflow rate from reservoir. Sensitivity studies were performed on temperature distribution to identify influential parameters out of the reservoir and hydraulic fracture parameters including reservoir porosity, reservoir permeability, fracture half-length, fracture height, fracture permeability, fracture porosity, fracture network parameters, and fracture interference between multiple clusters. In this work, in order to find contributions by a target fracture, temperature change sensitivity is evaluated. Single fracture case reveals that fracture permeability, network fracture parameters and fracture geometries are primary influential parameters on temperature change at the fracture location. And also, multiple fractures case shows that temperature change is augmented with the increase of fracture geometry and is decreased with the increase of fracture permeability. These results show the possibility of using temperature to determine these sensitive parameters, and also the quantified parameter sensitivities provide better understandings of the temperature behavior of horizontal well with multiple fractures.
10

Prediction Model for 3-Year Rupture Risk of Unruptured Cerebral Aneurysms in Japanese Patients / 日本人患者における未破裂脳動脈瘤の3年間の破裂危険性予測モデル

Tominari, Shinjiro 23 March 2016 (has links)
This is the peer reviewed version of the following article: Tominari, S., Morita, A., Ishibashi, T., Yamazaki, T., Takao, H., Murayama, Y., Sonobe, M., Yonekura, M., Saito, N., Shiokawa, Y., Date, I., Tominaga, T., Nozaki, K., Houkin, K., Miyamoto, S., Kirino, T., Hashi, K., Nakayama, T. and for the Unruptured Cerebral Aneurysm Study Japan Investigators (2015), Prediction model for 3-year rupture risk of unruptured cerebral aneurysms in Japanese patients. Ann Neurol., 77: 1050–1059. doi: 10.1002/ana.24400, which has been published in final form at http://dx.doi.org/10.1002/ana.24400. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19585号 / 医博第4092号 / 新制||医||1014(附属図書館) / 32621 / 京都大学大学院医学研究科医学専攻 / (主査)教授 古川 壽亮, 教授 小泉 昭夫, 教授 佐藤 俊哉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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