104 research outputs found
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Vacuum improvements for ultra high charge state ion acceleration
The installation of a second cryo panel has significantly improved the vacuum in the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The neutral pressure in the extraction region decreased from 1.2 x 10{sup {minus}6} down to about 7 x 10{sup {minus}7} Torr. The vacuum improvement reduces beam loss from charge changing collisions and enhances the cyclotron beam transmission, especially for the high charge state heavy ions. Tests with improved vacuum show the cyclotron transmission increased more than 50% (from 5.7% to 9.0%) for a Xe{sup 27+} at 603 MeV, more than doubled for a Bi{sup 41+} beam (from 1.9% to 4.6%) at 904 MeV and tripled for a U{sup 47+} beam (from 1.2% to 3.6%) at 1,115 MeV. At about 5 NeV/nucleon 92 enA (2.2 pnA) for Bi{sup 41+} and 14 enA (0.3 pnA) for U{sup 47+} were extracted ut of the 88-Inch Cyclotron Ion beams with charge states as high as U{sup 64+} have been produced by the LBNL AECR-U ion source and accelerated through the cyclotron for the first time. The beam losses for a variety of ultra high charge state ions were measured as a function of cyclotron pressure and compared with the calculations from the existing models
A system dynamics model of capital structure policy for firm value maximization
The complexity surrounding the maximization of firm value agenda demands a comprehensive causal model that effectively embeds the intertwining relationships of the variables and the policies involved. System dynamics provides an appropriate methodology to model and simulate such complex relationships to facilitate decision making in a complex business environment. The objective of the study is to analyze the impact of capital structure policy, being a key managerial decision, on the firm value. For this purpose, the study develops a system dynamics‐based corporate planning model for an oil firm, including the operational as well as financial processes. Various scenarios and capital structure policies have been designed and simulated to identify the policy that helps in increasing the firm value. The results demonstrate that increase in debt percentage in capital structure mix increase the firm value.publishedVersio
HIGH CURRENT BEAM EXTRACTION FROM THE 88-INCH CYCLOTRON AT LBNL
Abstract The low energy beam transport system and the inflector of the 88-Inch Cyclotron have been improved to provide more intense heavy-ion beams, especially for experiments requiring 48 Ca beams. In addition to a new spiral inflector [1] and increased injection voltage, the injection line beam transport and beam orbit dynamics in the cyclotron have been analyzed, new diagnostics have been developed, and extensive measurements have been performed to improve the transmission efficiency. By coupling diagnostics, such as emittance scanners in the injection line and a radially-adjustable beam viewing scintillator within the cyclotron, with computer simulations we have been able to identify loss mechanisms. The diagnostics used and their findings will be presented. We will discuss the solutions we have employed to address losses, such as changing our approach to tuning VENUS and running the cyclotron's central trim coil asymmetrically
Researchers' experience with project management in health and medical research: Results from a post-project review
<p>Abstract</p> <p>Background</p> <p>Project management is widely used to deliver projects on time, within budget and of defined quality. However, there is little published information describing its use in managing health and medical research projects. We used project management in the <it>Alcohol and Pregnancy Project </it>(2006-2008) <url>http://www.ichr.uwa.edu.au/alcoholandpregnancy</url> and in this paper report researchers' opinions on project management and whether it made a difference to the project.</p> <p>Methods</p> <p>A national interdisciplinary group of 20 researchers, one of whom was the project manager, formed the Steering Committee for the project. We used project management to ensure project outputs and outcomes were achieved and all aspects of the project were planned, implemented, monitored and controlled. Sixteen of the researchers were asked to complete a self administered questionnaire for a post-project review.</p> <p>Results</p> <p>The project was delivered according to the project protocol within the allocated budget and time frame. Fifteen researchers (93.8%) completed a questionnaire. They reported that project management increased the effectiveness of the project, communication, teamwork, and application of the interdisciplinary group of researchers' expertise. They would recommend this type of project management for future projects.</p> <p>Conclusions</p> <p>Our post-project review showed that researchers comprehensively endorsed project management in the <it>Alcohol and Pregnancy Project </it>and agreed that project management had contributed substantially to the research. In future, we will project manage new projects and conduct post-project reviews. The results will be used to encourage continuous learning and continuous improvement of project management, and provide greater transparency and accountability of health and medical research. The use of project management can benefit both management and scientific outcomes of health and medical research projects.</p
Workflow in Clinical Trial Sites & Its Association with Near Miss Events for Data Quality: Ethnographic, Workflow & Systems Simulation
10.1371/journal.pone.0039671PLoS ONE76
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The production of beams from solid materials at the LBL ECR source
Two ovens are described for the feed of vapor from solid materials in the LBL ECR source. A low temperature oven, operating up to 700 /degree/ C, has been used for Li, Mg, P, K, Ca, Ti and Bi. A high temperature oven operating up to 2000/degree/C, has been used for Sc, Fe, Ni, Cu, Ag, La and Tb. At the 1 e..mu..A level the charge states from the oven beams are very close to those from gases. 4 refs., 5 figs., 2 tabs
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