1,312 research outputs found
Space shuttle electromagnetic environment experiment. Phase A: Definition study
Methods for carrying out measurements of earth electromagnetic environment using the space shuttle as a measurement system platform are herein reported. The goal is to provide means for mapping intentional and nonintentional emitters on earth in the frequency range 0.4 to 40 GHz. A survey was made of known emitters using available data from national and international regulatory agencies, and from industry sources. The spatial distribution of sources, power levels, frequencies, degree of frequency re-use, etc., found in the survey, are here presented. A concept is developed for scanning the earth using a directive antenna whose beam is made to rotate at a fixed angle relative to the nadir; the illuminated area swept by the beam is of the form of cycloidal annulus over a sphere. During the beam's sojourn over a point, the receiver sweeps in frequency over ranges in the order of octave width using sweeping filter bandwidths sufficient to give stable readings
Space shuttle electromagnetic environment experiment. Phase A: Definition study
A program is discussed which develops a concept for measuring the electromagnetic environment on earth with equipment on board an orbiting space shuttle. Earlier work on spaceborne measuring experiments is reviewed, and emissions to be expected are estimated using, in part, previously gathered data. General relations among system parameters are presented, followed by a proposal on spatial and frequency scanning concepts. The methods proposed include a nadir looking measurement with small lateral scan and a circularly scanned measurement looking tangent to the earth's surface at the horizon. Antenna requirements are given, assuming frequency coverage from 400 MHz to 40 GHz. For the low frequency range, 400-1000 MHz, a processed, thinned array is proposed which will be more fully analyzed in the next phase of the program. Preliminary hardware and data processing requirements are presented
Metering Characteristics Accompanying Rate Changes Necessary for Precision Farming
Agricultural machines used in precision fanning must adjust application rates according to the needs of each cell within a field. Changing from an initial application rate to a new rate while the machine travels from one cell to another in the field is accompanied with some misapplication. The severity of this misapplication depends on the down-the-row delivery characteristics of the metering system and the magnitude of the rate change from cell to cell.
On-the-go rate change tests evaluated the down-the-row performance of an operator controlled metering system when increasing and decreasing wheat seeding rates by 10 and 20 kg/ha steps. The transition time from one cell to another ranged from 3 to 9 s depending upon the magnitude of the application rate change.
The difference between the initial and final seeding rate was based on a simple index. This separation index was based upon the initial and final down-the-row seeding rate distributions. When the separation index was greater than or equal to zero, the difference between the initial and final application rate was considered to be suitable for precision fanning. The separation criterion was always satisfied with 20 kg/ha rate changes. For 10 kg/ha rate changes, the separation index was negative in most cases. This indicated that rate changes of 10 kg/ha or less were unlikely to provide detectable rate differences as the metering rate variability exceeded the magnitude of the 10 kg/ha rate change
Metering Characteristics Accompanying Rate Changes Necessary for Precision Farming
Agricultural machines used in precision fanning must adjust application rates according to the needs of each cell within a field. Changing from an initial application rate to a new rate while the machine travels from one cell to another in the field is accompanied with some misapplication. The severity of this misapplication depends on the down-the-row delivery characteristics of the metering system and the magnitude of the rate change from cell to cell.
On-the-go rate change tests evaluated the down-the-row performance of an operator controlled metering system when increasing and decreasing wheat seeding rates by 10 and 20 kg/ha steps. The transition time from one cell to another ranged from 3 to 9 s depending upon the magnitude of the application rate change.
The difference between the initial and final seeding rate was based on a simple index. This separation index was based upon the initial and final down-the-row seeding rate distributions. When the separation index was greater than or equal to zero, the difference between the initial and final application rate was considered to be suitable for precision fanning. The separation criterion was always satisfied with 20 kg/ha rate changes. For 10 kg/ha rate changes, the separation index was negative in most cases. This indicated that rate changes of 10 kg/ha or less were unlikely to provide detectable rate differences as the metering rate variability exceeded the magnitude of the 10 kg/ha rate change
Variability in Volume Metering Devices
The inherent variability of seed and fertilizer application from volumetric metering devices is not readily recognized. The Canadian Prairie Agricultural Machinery Institute (P AMI) suggests a maximum coefficient of variation (CV) of 15% among outlets for seeding grain or applying fertilizer. P AMI does not report down-the-row variability of individual outlets. Parameters that influence variability of volumetric measuring external fluted wheels such as rotational speed of the metering wheel, product delivery rate, seed size, and cell collection lengths were examined.
In the first study, external fluted wheel meters on four grain drills were tested for seed delivery variability for wheat and soybeans, both among the metering outlets and down-the-row for individual meters. Tests on two additional drills, one an air drill and the other with external fluted metering, used two sizes of soybean seeds and two travel speeds. For wheat, down-the-row CV ranged from 12.5 to 22.5% and the CV among metering units ranged from 12.5 to 21 %. For soybeans, the CV ranged from 15.5 to 41.5% with the air drill having the lower CV. A faster travel speed gave a lower CV for both drills metering soybeans.
In a second study, when metering wheat, the seeding rate variability due to cell size and seeding rate were evaluated. Each meter was evaluated with cells 0.48 or 0.96 m in length and seeding rates of 60, 80,90, and 100 kg/ha. The down-the-row CV ranged from 10 to 28% with 0.48 m length cells, and from 4 to 22% with 0.96 m length cells. Some of these CVs may be too high for a metering mechanism such as the fluted wheel to be used in SSCM
Law as a Tool for Preventing Chronic Diseases: Expanding the Spectrum of Effective Public Health Strategies
Law, which is a fundamental element of effective public health policy and practice, played a crucial role in many of public health's greatest achievements of the 20th century. Still, conceptual legal frameworks for the systematic application of law to chronic disease prevention and control have not been fully recognized and used to address public health needs. Development and implementation of legal frameworks could broaden the range of effective public health strategies and provide valuable tools for the public health workforce, especially for state and local health department program managers and state and national policy makers. In an effort to expand the range of effective public health interventions, the Centers for Disease Control and Prevention will work with its partners to explore the development of systematic legal frameworks as a tool for preventing chronic diseases and addressing the growing epidemic of obesity, heart disease, stroke, and other chronic diseases and their risk factors
Other People’S Money: A Visual Technology for Teaching Corporate Restructuring Cross-Functionally
This article presents a detailed plan for using the movie Other People's Money as an integrative technology to teach organizational behavior and finance concepts crossfunctionally. The movie depicts corporate restructuring issues in a comic manner, while still conveying a message. It incorporates topics such as differing organizational models and perpectives, leadership, managerial goals, and stakeholder needs/wants. It also helps students learn about mergers and acquisitions including topics like takeovers, tender offers, and greenmail while stimulating thinking aout complex ethical issues. This teaching tool can be incorporated in undergraduate or graduate business classes, or as a module for management education in corporate settings. The teaching notes include a vocabulary list, suggested stopping points with discussion questions, and a set of postmovie questions to reinforce related concepts and motivate further study.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68685/2/10.1177_105256299902300106.pd
Spectroscopic factors for bound s-wave states derived from neutron scattering lengths
A simple and model-independent method is described to derive neutron
single-particle spectroscopic factors of bound s-wave states in nuclei from neutron scattering lengths. Spectroscopic factors
for the nuclei ^{13}C, ^{14}C, ^{16}N, ^{17}O, ^{19}O, ^{23}Ne, ^{37}Ar, and
^{41}Ar are compared to results derived from transfer experiments using the
well-known DWBA analysis and to shell model calculations. The scattering length
of ^{14}C is calculated from the ^{15}C_{g.s.} spectroscopic factor.Comment: 9 pages (uses revtex), no figures, accepted for publication in PRC,
uuencoded tex-files and postscript-files available at
ftp://is1.kph.tuwien.ac.at/pub/ohu/Thermal.u
SIMPATIQCO: A server-based software suite which facilitates monitoring the time course of LC-MS performance metrics on orbitrap instruments
While the performance of liquid chromatography (LC) and mass spectrometry (MS) instrumentation continues to increase, applications such as analyses of complete or near-complete proteomes and quantitative studies require constant and optimal system performance. For this reason, research laboratories and core facilities alike are recommended to implement quality control (QC) measures as part of their routine workflows. Many laboratories perform sporadic quality control checks. However, successive and systematic longitudinal monitoring of system performance would be facilitated by dedicated automatic or semiautomatic software solutions that aid an effortless analysis and display of QC metrics over time. We present the software package SIMPATIQCO (SIMPle AuTomatIc Quality COntrol) designed for evaluation of data from LTQ Orbitrap, Q-Exactive, LTQ FT, and LTQ instruments. A centralized SIMPATIQCO server can process QC data from multiple instruments. The software calculates QC metrics supervising every step of data acquisition from LC and electrospray to MS. For each QC metric the software learns the range indicating adequate system performance from the uploaded data using robust statistics. Results are stored in a database and can be displayed in a comfortable manner from any computer in the laboratory via a web browser. QC data can be monitored for individual LC runs as well as plotted over time. SIMPATIQCO thus assists the longitudinal monitoring of important QC metrics such as peptide elution times, peak widths, intensities, total ion current (TIC) as well as sensitivity, and overall LC-MS system performance; in this way the software also helps identify potential problems. The SIMPATIQCO software package is available free of charge
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