9,478 research outputs found
Heat exchanger test experimental apparatus. Section I - Helium heater. Section II - Helium circulator Summary report
Molybdenum heater tube for heating helium to operating temperature of high temperature heat exchanger facility - performance of helium circulato
USE OF ALTERNATIVE DEPRECIATION METHODS TO ESTIMATE FARM TRACTOR VALUES
Six depreciation methods were used to simulate the value of farm tractors with indexed and expected prices. Accuracy of simulated values was evaluated using paired t-tests of mean absolute percentage errors and forecast accuracy regression models. Results varied with age and use. Some depreciation methods were more accurate than others.Farm Management, Financial Economics,
Creating multi-vendor solutions: the resources and capabilities required.
Purpose
– The purpose of this paper is to investigate the resources and capabilities required by manufacturers to develop and deliver multi-vendor solutions.
Design/methodology/approach
– A multi-case design comprising six UK-based manufacturers: two from each of the aerospace/defence, information technology and telecommunications sectors.
Findings
– Manufacturers can be characterized by their propensity to include products from other vendors in their solutions; single vendor solution providers (SVSPs) focus on solutions comprising their own products, while multi-vendor solution providers (MVSPs) fully embrace products from other manufacturers. Three capabilities were identified which distinguish MVSPs from SVSPs given the complexity of multi-vendor solutions (expertise specifying the solution, engineers trained in implementing/supporting the solution, partnerships with component suppliers of the solution). These capabilities are underpinned by both technical capability and impartiality in solution specification.
Research limitations/implications
– MVSPs need to be impartial when specifying customer solutions. They should be guided by the best interests of the customer rather than the interests of the product-based SBUs. Achieving impartiality can conflict with some manufacturers' product heritage. The research has focused on three sectors; further research is needed to test whether the findings are applicable beyond these sectors.
Practical implications
– Solutions are a valuable approach in creating market differentiation, although not all manufacturers will possess the resources/capabilities to be successful.
Originality/value
– A continuum of solution providers is proposed; SVSPs at one extreme and MVSPs at the other. The operant resource-based capability “impartiality” was identified as being particularly important to MVSPs in creating value for customers.
</jats:sec
The inexorable resistance of inertia determines the initial regime of drop coalescence
Drop coalescence is central to diverse processes involving dispersions of
drops in industrial, engineering and scientific realms. During coalescence, two
drops first touch and then merge as the liquid neck connecting them grows from
initially microscopic scales to a size comparable to the drop diameters. The
curvature of the interface is infinite at the point where the drops first make
contact, and the flows that ensue as the two drops coalesce are intimately
coupled to this singularity in the dynamics. Conventionally, this process has
been thought to have just two dynamical regimes: a viscous and an inertial
regime with a crossover region between them. We use experiments and simulations
to reveal that a third regime, one that describes the initial dynamics of
coalescence for all drop viscosities, has been missed. An argument based on
force balance allows the construction of a new coalescence phase diagram
Master agreement task order 2 - Analyses and limited evaluations of payload and landing system structures for the survivable soft landing of instrument payloads
Computer programs for analysis and evaluation of payload and landing system structures for soft landing of instrument package
The Origin of Tunneling Anisotropic Magnetoresistance in Break Junctions
First-principles calculations of electron tunneling transport in Ni and Co
break junctions reveal strong dependence of the conductance on the
magnetization direction, an effect known as tunneling anisotropic
magnetoresistance (TAMR). The origin of this phenomenon stems from resonant
states localized in the electrodes near the junction break. The energy and
broadening of these states is strongly affected by the magnetization
orientation due to spin-orbit coupling, causing TAMR to be sensitive to bias
voltage on a scale of a few mV. Our results bear a resemblance to recent
experimental data and suggest that TAMR driven by resonant states is a general
phenomenon typical for magnetic broken contacts and other experimental
geometries where a magnetic tip is used to probe electron transport.Comment: 4 pages, 3 figure
Future Crop Prices and Quantities: Influence of Alternative Crop Yields
Many people have tried to analyze what the future holds for continued increases in crop yields. After studying time series of average U.S. yields for 19 crops, Lin and Seaver [6] concluded that 12 crops including corn, cotton, and wheat have reached yield plateau, and the seven remaining crops including hay and soybeans yields have had a slowdown in their rate of growth. On the other hand, after presenting some of the possible new technologies or changes in existing technologies that could boast yields, Wittwer [15] concluded that it is reasonable to expect possible large increases in yields. Wittwer\u27s list of possible technologies included: changes in the plants\u27 ability to withstand environmental stress; changes in the plants\u27 ability to utilize fertilizer including the possibility of more plants with nitrogen fixation capabilities; increases in the plants\u27 photosynthetic efficiency; and increases in the use of chemical growth regulators. Heady [5], after reviewing a host of other studies, observed that probably the best that can be hoped for in the future is the continuation of the current absolute increases in yields
A Tatonnement Model for Determining Future Market Prices and Quantities for some U.S. Crops
People concerned with planning and analysis of the agricultural sector are faced with two general problems which in turn gives rise for two general types of models. One problem involves positive or predictive models which attempt to predict the real world as it actually exists based on response functions. Models directed towards these types of predictions are usually based on time series observations and use statistical estimation techniques such as regression equations. The second problem involves normative models, which ask the question: what conditions could prevail if certain conditions and goals were to be met? Frequently, these conditions have never prevailed in the past and time series observations do not exist. Problems of this type cannot be handled by time-series regression models but more nearly involve some type of operations research methods. Specific techniques in the set of possibilities include mathematical programming and systems simulation. Mathematical programming models lend themselves to great detail on spatial characteristics of agriculture that cannot be accomplished with time-series regression models
Updated Information on the Local Group
The present note updates the information published in my recent monograph on
\underline{The Galaxies of the Local Group}. Highlights include (1) the
addition of the newly discovered Cetus dwarf spheroidal as a certain member of
the Local Group, (2) an improved distance for SagDIG, which now places this
object very close to the edge of the Local Group zero-velocity surface, (3)
more information on the evolutionary histories of some individual Local Group
members, and (4) improved distance determinations to, and luminosities for, a
number of Local Group members. These data increase the number of certain (or
probable) Local Group members to 36. The spatial distribution of these galaxies
supports Hubble's claim that the Local Group ``is isolated in the general
field.'' Presently available evidence suggests that star formation continued
much longer in many dwarf spheroidals than it did in the main body of the
Galactic halo. It is suggested that ``young'' globular clusters, such as
Ruprecht 106, might have formed in now defunct dwarf spheroidals. Assuming
SagDIG, which is the most remote Local Group galaxy, to lie on, or just inside,
the zero-velocity surface of the Local Group yields a dynamical age \gtrsim
17.9 \pm 2.7 Gyr.Comment: 19 pages, 1 figure, to be published in the April 2000 issue of PAS
- …