2,950 research outputs found
A Qualitative Evaluation of the Effectiveness of Louisiana Cooperative Extension Service Cotton Advisory Committees Using Focus Group Interviews.
The primary purpose of this study was to determine the effectiveness of Extension cotton advisory committees as perceived by parish Extension agents and clientele. The study was conducted statewide, in Louisiana, with a selected sample Extension agents and clientele representing the two major cotton-producing areas of the state. The data was obtained through six focus group interviews. Standard methodology for qualitative data was used in the analysis. Four focus group interviews involved cotton advisory committee members, and two involved Extension agents. Nineteen Louisiana parishes were targeted in the study. Study conclusions included the following: (a) advisory committees strongly influence decision making, (b) members are strongly involved in advisement, have some involvement in legitimation and communication, but no involvement; in interpretation, (c) members have strong involvement in implementation, weak in planning, and none in evaluation, (d) members perceive serving on the advisory committee as positive, (e) the advisory committee process should continue to function, and (f) speed of information delivery and developing sound working relationships are the major problems and educational programs are needed in marketing, biotechnology, pesticide record keeping, and integrated pest management. Based on the findings outlined above, the following recommendations were made by the researcher for improving cotton advisory committees and Extension programming: (1) Establish one parish advisory committee to cover all crops. (2) Focus on more effective representation and participation. (3) Recruit and involve more young producers. (4) Equip agents with a better understanding of the advisory committee process. (5) Utilize the Internet to speed delivery of information. (6) Create and staff area specialists positions in the cotton-producing areas of Louisiana. (7) Utilize the program areas of 4-H and home economics to convey information. (8) Future research to determine effective methods to involve clientele. (9) Determine effective training methods to assist agents and clientele in understanding the advisory committee process. (10) Study the roles that agents and clientele are playing in the advisory process. (11) Conduct case studies of parishes that have successful advisory committees. (12) A study to determine the perceptions of consultants, agribusiness, and research personnel related to cotton education programs. (13) Study the effectiveness of Extension education programs
Toward a Bias Corrected Currency Equivalent Index
Measuring the economic stock of money, defined to be the present value of current and future monetary service flows, is a difficult asset pricing problem, because most monetary assets yield interest. Thus, an interest yielding monetary asset is a joint product: a durable good providing a monetary service flow and a financial asset yielding a return. The currency equivalent index provides an elegant solution, but it does so by making strong assumptions about expectations of future monetary service flows. These assumptions cause the currency equivalent index to exhibit significant downward bias. In this paper, we propose an extension to the currency equivalent index that will correct for a significant amount of this bias.Currency equivalent index, monetary aggregation, money stock
Retrodiction with two-level atoms: atomic previvals
In the Jaynes-Cummings model a two-level atom interacts with a single-mode
electromagnetic field. Quantum mechanics predicts collapses and revivals in the
probability that a measurement will show the atom to be excited at various
times after the initial preparation of the atom and field. In retrodictive
quantum mechanics we seek the probability that the atom was prepared in a
particular state given the initial state of the field and the outcome of a
later measurement on the atom. Although this is not simply the time reverse of
the usual predictive problem, we demonstrate in this paper that retrodictive
collapses and revivals also exist. We highlight the differences between
predictive and retrodictive evolutions and describe an interesting situation
where the prepared state is essentially unretrodictable.Comment: 15 pages, 3 (5) figure
Effects of Purified Salmonella enteritidis Endotoxin on the Immune Response of Balb/c Mice
Wasting disease was produced in neonatal Balb/c mice with purified Salmonella enteritidis endotoxins. The endotoxins were chemically characterized to provide the study with a potent endotoxin with constant biological activity. Neonatal mice received an initial injection of 35 μg/g body weight of endotoxin and a dose of 75 μg every third day until day 18. The degree of wasting was estimated by the runting (weight loss) index. Mortality was calculated to be 46%, with a mean survival time of approximately 15 days. The hematologic studies conducted at days 10, 20, and 30 showed an absolute neutrophilia and leukocytosis by day 10 which persisted to day 30. Immunologic data indicated that the responsiveness to sheep erythrocytes was depressed to day 20 and continued to persist at day 30. It was postulated that endotoxin either directly or indirectly affects the immune apparatus which allows the normal flora of the animal to establish an infection leading to wasting and death
Retrodiction as a tool for micromaser field measurements
We use retrodictive quantum theory to describe cavity field measurements by
successive atomic detections in the micromaser. We calculate the state of the
micromaser cavity field prior to detection of sequences of atoms in either the
excited or ground state, for atoms that are initially prepared in the excited
state. This provides the POM elements, which describe such sequences of
measurements.Comment: 20 pages, 4(8) figure
Maximum Confidence Quantum Measurements
We consider the problem of discriminating between states of a specified set
with maximum confidence. For a set of linearly independent states unambiguous
discrimination is possible if we allow for the possibility of an inconclusive
result. For linearly dependent sets an analogous measurement is one which
allows us to be as confident as possible that when a given state is identified
on the basis of the measurement result, it is indeed the correct state.Comment: 4 pages, 2 figure
Enhancing space transportation: The NASA program to develop electric propulsion
The NASA Office of Aeronautics, Exploration, and Technology (OAET) supports a research and technology (R and T) program in electric propulsion to provide the basis for increased performance and life of electric thruster systems which can have a major impact on space system performance, including orbital transfer, stationkeeping, and planetary exploration. The program is oriented toward providing high-performance options that will be applicable to a broad range of near-term and far-term missions and vehicles. The program, which is being conducted through the Jet Propulsion Laboratory (JPL) and Lewis Research Center (LeRC) includes research on resistojet, arcjets, ion engines, magnetoplasmadynamic (MPD) thrusters, and electrodeless thrusters. Planning is also under way for nuclear electric propulsion (NEP) as part of the Space Exploration Initiative (SEI)
Non-Markovian dynamics of a qubit
In this paper we investigate the non-Markovian dynamics of a qubit by
comparing two generalized master equations with memory. In the case of a
thermal bath, we derive the solution of the post-Markovian master equation
recently proposed in Ref. [A. Shabani and D.A. Lidar, Phys. Rev. A {\bf 71},
020101(R) (2005)] and we study the dynamics for an exponentially decaying
memory kernel. We compare the solution of the post-Markovian master equation
with the solution of the typical memory kernel master equation. Our results
lead to a new physical interpretation of the reservoir correlation function and
bring to light the limits of usability of master equations with memory for the
system under consideration.Comment: Replaced with published version (minor changes
Heavy ion beam lifetimes at relativistic and ultrarelativistic colliders
The effects of higher order corrections in ultra-relativistic nuclear
collisions are considered. It is found that higher order contributions are
small at low energy, large at intermediate energy and small again at very high
energy. An explanation for this effect is given. This means that the
Weizsacker-Williams formula is a good approximation to use in calculating cross
sections and beam lifetimes at energies relevant to RHIC and LHC.Comment: 10 pages, 2 tables, 4 figure
Hypercars: The next industrial revolution
The auto industry -- one-seventh of the GNP, and the highest expression of the Iron Age -- is about to trigger the biggest transformation in industrial structure since the microchip. Ultralight cars molded from net-shape advanced composites can be several-fold lighter than present steel cars, yet safer, sportier, and more comfortable, durable, and beautiful. Modern hybrid-electric drives boost efficiency approximately 1.3-1.5x in heavy steel cars, but approximately 5-20x in ultralight, very slippery plafforms. Synergistically combined into ultralight-hybrid 'hypercars,' these elements can yield state-of-the-shelf family cars that average 150-300+ mi/gal -- twice that with state-of-the-art technologies -- yet can also be superior in all other respects, probably including cost: carbon-fiber monocoques can actually be cheaper to mass-produce that steel unibodies. Designing cars more like aircraft and less like tanks requires not only an approximately 400-500 kg curb mass and very low air and road drag, but also an aerospace philosophy of engineering integration. Mass, cost, and complexity turn out to compound with heavy hybrids but to decompound with ultralight hybrids, owing partly to radical simplification. Excellent aerodynamics, preferable including advanced techniques for passive boundary-layer control, will be the key to successful design integration. Transforming automaking is a competitive and environmental imperative, could form the nucleus of a green industrial Renaissance, and would enhance national security by, among other things, saving as much oil as OPEC now extracts. However, this transformation faces serious cultural barriers. For example, hypercars will be more like computers with wheels than like cars with chips -- they'll have an order of magnitude more code than today's cars -- but Detroit is not a software culture. Just the transition from stamped and welded steel to integrated and adhesive-joined synthetics is difficult enough. Nonetheless, hypercars are rapidly heading to market in the late 1990s, because approximately 25 current and intending automakers are eager to capture their potentially decisive competitive advantages -- including order-of-magnitude reductions in product cycle time, tooling cost, assembly effort, and parts count. Hypercars will succeed, and may well sweep the market, not because of mandates or subsidies, but because of manufacturers' quest for competitive advantage and customers' desire for better, smarter cars
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