27 research outputs found
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Willamette subbasin summary : draft
Draft report prepared for the Northwest Power Planning Council.Keywords: Fish and Wildlife, Willamette Valley Ecoregion, Willamette River Basin, Watersheds, Willamette River (Or.), Basins, Managemen
Positional Reproducibility and Effects of a Rectal Balloon in Prostate Cancer Radiotherapy
Despite the increasing use of the rectal balloon in prostate cancer radiotherapy, many issues still remain to be verified objectively including its positional reproducibility and relevance to treatment morbidity. We have developed a custom rectal balloon that has a scale indicating the depth of insertion and dilates symmetrically ensuring positional reproducibility. Fifty patients with prostate cancer treated by definitive 3D-conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) with rectal balloon were analyzed. Each of first five patients undergone computed tomography (CT) three times with a rectal balloon. The positional reproducibility was tested by Intraclass Correlation Coefficient (ICC) from the CT-to-CT fusion images. Planning variables and clinical acute toxicities were compared between when or not applying balloon. An ICC of greater than 0.9 in all directions revealed an excellent reproducibility of the balloon. Rectal balloon improved considerably the mean dose and V45Gy-V65Gy in plan comparison, and especially in 3D-CRT the rectal volume exposed to more than 60 Gy dropped from 41.3% to 19.5%. Clinically, the balloon lowered acute toxicity, which was lowest when both the balloon and IMRT were applied simultaneously. The rectal balloon carries excellent reproducibility and reduces acute toxicity in 3D-CRT and IMRT for prostate cancer
Acute gastrointestinal and genitourinary toxicity of image-guided intensity modulated radiation therapy for prostate cancer using a daily water-filled endorectal balloon
Waters of Oregon: A Source Book on Oregon's Water and Water Management
2 p. Review produced for HC 441: Science Colloquium: Willamette River Environmental Health, Robert D. Clark Honors College, University of Oregon , Spring term, 2004.Print copies of the reviewed book are available in several collections within the UO Libraries, under the call number: TD224.O7 B37 199
Evaluation of slug tests in a bounded, phreatic, sand and gravel aquifer
The purpose of this research was to compare hydraulic conductivity estimates in a bounded phreatic aquifer derived from slug tests to those calculated from more accurate and costly tracer tests. A slug test is a simple method to estimate the hydraulic conductivity of near well material by recording the water level in the well after the instantaneous removal of a known volume of water. The pneumatic method was modified so that it could be used to initiate the slug tests in water table wells. The slug tests were conducted according to new guidelines proposed by the Kansas Geologic Survey (KGS) and analyzed with a new semi-analytical solution (the KGS model) which eliminates many of the simplifying assumptions in the widely accepted models. The slug test estimates were found to underestimate the tracer results by up to a factor of 5
Now Hear This! What All Environmental Engineers Should Know About Noise Control
Noise is an is an that affects almost everyone. And even though environmental engineers are often called on to deal with noise-related problems, most of them receive little or no academic training in noise control. This primer suggests why all environmental engineers should know something about noise control, what they need to know, and where they can find the necessary information
Interview with Rick Bastasch
Rick Bastasch was interviewed by Michael Rupp and Jim Knight on May 10, 2017.
A lifelong Oregonian, Rick Bastasch is the author of The Oregon Water Handbook (Oregon State University Press, 2006). He worked with the Oregon Water Resources Department for over a decade, specializing in river basin planning, intergovernmental coordination, public information, and legislative analysis. He has also led recent efforts to conserve and restore the Willamette River.https://pdxscholar.library.pdx.edu/planoregon_interviews/1039/thumbnail.jp
WIND TURBINE GENERATOR NOISE PREDICTION -COMPARISON OF COMPUTER MODELS
Abstract The development of wind turbine generators as alternative sources of energy supply is a growing fact both in Australia and worldwide. One of the many aspects of the environmental impact assessment process for new wind farms is the prediction of their noise impacts (immissions). As well as the assessment of objective sound levels for environmental noise, the other main activity in assessing their noise impact is the prediction of receiver sound levels caused by emissions of noise from the wind turbine generators (WTG's). There are a number of computer noise models available for the prediction of environmental noise, as well as some specifically designed for noise emissions from WTG's. This paper presents the results of modeling for a typical wind turbine generator using three different prediction models. There is a significant difference between the predicted results using a noise model designed for static industrial sources, compared to algorithms or models designed specifically for WTG's. The main difference appears to be the method in which elevated sources are computed. A significant contributor to WTG noise is aerodynamic noise from each blade tip. These blades can vary in height by as much as 80m per revolution and have an axis 60 to 80m above ground. Wind farm noise emissions also increase with wind speed (typically from 4 to 12m/s), as does associated background noise. This makes the monitoring of background sound levels over the range of operating wind conditions also important. Selection of accurate prediction models for WTG's will enable a better assessment of the noise impacts from wind farms to be made
What Should Environmental Engineers Know About Noise Control?
Noise is an issue that affects everyone. It is a problem that often becomes the responsibility of Environmental Engineers. Currently, most receive little academic training in Noise Control. This paper explores the reasons why Environmental Engineers need to know something about noise and what they need to know. In addition to recommending that graduating Environmental Engineers are exposed to Noise Control, this paper suggests some available resources
Now Hear This! What All Environmental Engineers Should Know About Noise Control
Environmental engineers are often called on to deal with noise-related problems. Noise affects health and quality of life for all of us. In summary, noise control should be of interest to environmental engineers for the following key reasons 1. Understanding the fundamentals is within every engineer\u27s grasp and engineers are already familiar with the operating principles of process equipment (e.g., fans, pumps, motors). This gives them an advantage in designing solutions to noise issues or avoiding problems in the first place. 2. Environmental engineers should have a good understanding of noise-related regulations as they may find themselves working in a health and safety role. 3. Understanding the difference between sound pressure level and sound power level is important for all disciplines that may be specifying equipment. Understanding why 85 dB (A) at 3 feet-although a standard specification-is not appropriate in many cases is one example. 4. Since the regulatory framework is fractured, 16 environmental engineers and planners who may eventually be involved in site selection/project development should have a clear understanding of noise when designing or approving projects. 5. It is more effective both in terms of mitigation and cost to address noise early in the design process rather than as a retrofit. If new engineers aren\u27t exposed to this, they won\u27t know how to identify problems before they arise or how to appropriately solve them after they occur. Finally, if environmental engineers aren\u27t concerned with noise control, then who should be