Comparison of 2-way versus metered 3-way boom shut-off valves for automatic section control on agricultural sprayers

Modern spray rate controllers along with technologies such as automatic section control (ASC) provide benefits such as overlap reduction on agricultural sprayers. However, product (liquid) dynamics within the boom plumbing affect off-rate errors and application uniformity during rate changes and ASC actuation. Therefore, this study was conducted to compare nozzle flow stability and uniformity across the boom when using two different boom shut-off valves (2-way and metered 3-way) on an 18.3-m sprayer boom. Pressure transducers were mounted at 1) the boom manifold, 2) randomly at 12 nozzle bodies across the spray boom, and 3) upstream and downstream of the flow regulating valve. Effective system flow rate was measured using two flow meter(s), one located upstream of the boom control valves (2-way or metered 3-way) and another mounted to measure the tank return flow for the metered 3-way boom valve. Measured nozzle pressure was converted to nozzle flow using the manufacturer’s pressure-flow data. Results indicated that the 2-way boom versus metered 3-way valve response was significantly different. Significant differences in damping ratios were found when exiting (under-damped) and reentering (over-damped) of spray zones. For the metered 3-way boom valve configuration, nozzle flow settled faster (0.1 to 4.2 s) virtually eliminating off-rate errors whereas the 2-way boom valve configuration took up to 34.3 s to settle with off-rate errors ranging from 3.3% to 11.5%. The delayed nozzle flow settling times were associated with pressure settling (0.7 to 31.4 s) downstream of the regulating valve for the 2-way configuration. Ground speed and point row angle impacted nozzle flow settling times and off-rate errors. The increase in ground speed and point row angle increased nozzle flow settling time for the 2-way valve setup, except that acceleration decreased settling times when exiting spray zones. The delayed response contributed to off-rate time which decreased as the sprayer accelerated and point row angle decreased for both the 2-way (1.7 to 19.3 s) and metered 3-way (2.1 to 4.4 s) boom shut-off valve setups

A New Way to Measure the World's Protected Area Coverage

Protected areas are effective at stopping biodiversity loss, but their placement is constrained by the needs of people. Consequently protected areas are often biased toward areas that are unattractive for other human uses. Current reporting metrics that emphasise the total area protected do not account for this bias. To address this problem we propose that the distribution of protected areas be evaluated with an economic metric used to quantify inequality in income— the Gini coefficient. Using a modified version of this measure we discover that 73% of countries have inequitably protected their biodiversity and that common measures of protected area coverage do not adequately reveal this bias. Used in combination with total percentage protection, the Gini coefficient will improve the effectiveness of reporting on the growth of protected area coverage, paving the way for better representation of the world's biodiversity

Mycobacterium ulcerans treatment - can antibiotic duration be reduced in selected patients?

Mycobacterium ulcerans (M. ulcerans) is a necrotizing skin infection endemic to the Bellarine Peninsula, Australia. Current treatment recommendations include 8 weeks of combination antibiotics, with adjuvant surgery if necessary. However, antibiotic toxicity often results in early treatment cessation and local experience suggests that shorter antibiotic courses may be effective with concurrent surgery. We report the outcomes of patients in the Barwon Health M. ulcerans cohort who received shorter courses of antibiotic therapy than 8 weeks

The demise of the randomised controlled trial: bibliometric study of the German-language health care literature, 1948 to 2004

BACKGROUND: In order to reduce systematic errors (such as language bias) and increase the precision of the summary treatment effect estimate, a comprehensive identification of randomised controlled trials (RCT), irrespective of publication language, is crucial in systematic reviews and meta-analyses. We identified trials in the German general health care literature. METHODS: Eight German language general health care journals were searched for randomised controlled trials and analysed with respect to the number of published RCTs each year and the size of trials. RESULTS: A total of 1618 trials were identified with a median total number of 43 patients per trial. Between 1970 and 2004 a small but constant rise in sample size from a median number of 30 to 60 patients per trial can be observed. The number of published trials was very low between 1948 and 1970, but increased between 1970 and 1986 to a maximum of 11.2 RCTs per journal and year. In the following time period a striking decline of the number of RCTs was observed. Between 1999 and 2001 only 0.8 RCTs per journal and year were published, in the next three years, the number of published trials increased to 1.7 RCTs per journal and year. CONCLUSION: German language general health care journals no longer have a role in the dissemination of trial results. The slight rise in the number of published RCTs in the last three years can be explained by a change of publication language from German to English of three of the analysed journals

Detection of Ly\beta auto-correlations and Ly\alpha-Ly\beta cross-correlations in BOSS Data Release 9

The Lyman-$\beta$ forest refers to a region in the spectra of distant quasars that lies between the rest-frame Lyman-$\beta$ and Lyman-$\gamma$ emissions. The forest in this region is dominated by a combination of absorption due to resonant Ly$\alpha$ and Ly$\beta$ scattering. When considering the 1D Ly$\beta$ forest in addition to the 1D Ly$\alpha$ forest, the full statistical description of the data requires four 1D power spectra: Ly$\alpha$ and Ly$\beta$ auto-power spectra and the Ly$\alpha$-Ly$\beta$ real and imaginary cross-power spectra. We describe how these can be measured using an optimal quadratic estimator that naturally disentangles Ly$\alpha$ and Ly$\beta$ contributions. Using a sample of approximately 60,000 quasar sight-lines from the BOSS Data Release 9, we make the measurement of the one-dimensional power spectrum of fluctuations due to the Ly$\beta$ resonant scattering. While we have not corrected our measurements for resolution damping of the power and other systematic effects carefully enough to use them for cosmological constraints, we can robustly conclude the following: i) Ly$\beta$ power spectrum and Ly$\alpha$-Ly$\beta$ cross spectra are detected with high statistical significance; ii) the cross-correlation coefficient is $\approx 1$ on large scales; iii) the Ly$\beta$ measurements are contaminated by the associated OVI absorption, which is analogous to the SiIII contamination of the Ly$\alpha$ forest. Measurements of the Ly$\beta$ forest will allow extension of the usable path-length for the Ly$\alpha$ measurements while allowing a better understanding of the physics of intergalactic medium and thus more robust cosmological constraints.Comment: 26 pages, 10 figures; matches version accepted by JCA

Coal Ash Corrosion Resistant Materials Testing

In April 1999, three identical superheater test sections were installed into the Niles Unit No.1 for the purpose of testing and ranking the coal ash corrosion resistance of candidate superheater alloys. The Niles boiler burns high sulfur coal (3% to 3.5%) that has a reasonably high alkali content, thus the constituents necessary for coal ash corrosion are present in the ash. The test sections were controlled to operate with an average surface metal temperature from approximately 1060 F to 1210 F which was well within the temperature range over which coal ash corrosion occurs. Thus, this combination of aggressive environment and high temperature was appropriate for testing the performance of candidate corrosion-resistant tube materials. Analyses of the deposit and scale confirmed that the aggressive alkali-iron-trisulfate constituent was present at the metal surface and active in tube metal wastage. The test sections were constructed so that the response of twelve different candidate tube and/or coating materials could be studied. The plan was to remove and evaluate one of the three test sections at time intervals of 1 year, 3 years, and 5 years. This would permit an assessment of performance of the candidate materials as a function of time. This report provides the results of the evaluation of Test Section C, including the samples that remained in the Test Section for the full exposure period as well as those that were removed early. The analysis of Test Section C followed much the same protocol that was employed in the assessment of Test Section A. Again, the focus was on determining and documenting the relative corrosion rates of the candidate materials. The detailed results of the investigation are included in this report as a series of twelve appendices. Each appendix is devoted to the performance of one of the candidate alloys. The table below summarizes metal loss rate for the worst case sample of each of the candidate materials for both Test Sections A and C. The body of this report compares these for all of the samples in the test section. The 'Coal Ash Corrosion Resistant Materials Testing Program' is being conducted by The Babcock & Wilcox Company (B&W), the U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) at Reliant Energy's Niles plant in Niles, Ohio to provide full-scale, in-situ testing of recently developed boiler superheater materials. Fireside corrosion is a key issue for improving efficiency of new coal fired power plants and improving service life in existing plants. In November 1998, B&W began development of a system to permit testing of advanced tube materials at metal temperatures typical of advanced supercritical steam temperatures (1100 F and higher) in a boiler exhibiting coal ash corrosive conditions. Several materials producers including Oak Ridge National Laboratory (ORNL) contributed advanced materials to the project. In the spring of 1999 a system consisting of three identical sections, each containing multiple segments of twelve different materials, was installed. The sections are cooled by reheat steam, and are located just above the furnace entrance in Niles Unit No.1, a 110 MWe unit firing high sulfur Ohio coal. In November 2001 the first section was removed for thorough metallurgical evaluation after 29 months of operation. The second section was removed in August of 2003. Its evaluation has been completed and is the subject of this report. The final section remains in service and is expected to be removed in the spring of 2005. This paper describes the program; its importance, the design, fabrication, installation and operation of the test system, materials utilized, and experience to date. This report briefly reviews the results of the evaluation of the first section and then presents the results of the evaluation of the second section

The Linear Theory Power Spectrum from the Lyman-alpha Forest in the Sloan Digital Sky Survey

We analyze the SDSS Ly-alpha forest P_F(k,z) measurement to determine the linear theory power spectrum. Our analysis is based on fully hydrodynamic simulations, extended using hydro-PM simulations. We account for the effect of absorbers with damping wings, which leads to an increase in the slope of the linear power spectrum. We break the degeneracy between the mean level of absorption and the linear power spectrum without significant use of external constraints. We infer linear theory power spectrum amplitude Delta^2_L(k_p=0.009s/km,z_p=3.0)=0.452_{-0.057-0.116}^{+0.069+0.141} and slope n_eff=-2.321_{-0.047-0.102}^{+0.055+0.131} (possible systematic errors are included through nuisance parameters in the fit - a factor >~5 smaller errors would be obtained on both parameters if we ignored modeling uncertainties). The errors are correlated and not perfectly Gaussian, so we provide a chi^2 table to accurately describe the results. The result corresponds to sigma_8=0.85, n=0.94, for a LCDM model with Omega_m=0.3, Omega_b=0.04, and h=0.7, but is most useful in a combined fit with the CMB. The inferred curvature of the linear power spectrum and the evolution of its amplitude and slope with redshift are consistent with expectations for LCDM models, with the evolution of the slope, in particular, being tightly constrained. We use this information to constrain systematic contamination, e.g., fluctuations in the UV background. This paper should serve as a starting point for more work to refine the analysis, including technical improvements such as increasing the size and number of the hydrodynamic simulations, and improvements in the treatment of the various forms of feedback from galaxies and quasars.Comment: Improved presentation, including fit results for (z). Simple code to produce LyaF chi^2 given linear power spectrum available at: http://www.cita.utoronto.ca/~pmcdonal/code.htm

Effects of ethical leadership on emotional exhaustion in high moral intensity situations

© 2015 Elsevier Inc. Emotional exhaustion is a threat to standard operations, particularly in organizations in which physical safety is at risk. High moral intensity is inherent in such organizations due to the magnitude of consequences associated with ethical/unethical conduct. The authors proposed a psychological process in which ethical leadership affects emotional exhaustion directly and indirectly through team cohesion. As military operational contexts typically are (or frequently have the potential to become) high moral intensity situations, the authors tested their model among 338 military personnel deployed in combat zones. They found that: (1) team cohesion partially mediated the relationship between ethical leadership and emotional exhaustion, and (2) this psychological process of direct and indirect effects of ethical leadership did not hold among individuals approaching the low end of conscientiousness