Growing-Degree Units For Selected Agricultural Locations In Alaska

Paper copies in Archives, Acc #:2013-0059It is well known that the rate at which a plant grows is influenced by air temperature. The problem is to define this relationship in a quantitative manner so that the information can be applied to agricultural problems. In places where growth of a particular crop is limited by the length of the growing season, an evaluation of the "heat-units" available is particularly important. Many heat-unit systems have evolved over the years, with certain advantages claimed for each. In crop production, heat unit systems are used to estimate the time required for a crop to go from one stage of development to another, usually from planting to harvest. Each heat-unit system produces a particular set of values, the values being determined by the relationship between temperature and growth that is assumed in the calculations. This paper lists heat-units available in six areas in Alaska, all having agricultural potential. The system used measures temperature in "growing-degree units" and is described in detail. Recent comparative studies of growing season and growing degree days leads to the conclusion that the temperature records taken at Big Delta may have been favorably affected by the nearness of the weather recording station to an extensive coated runway. The "flywheel" effect of this large heat sink appear to have reduced the occurrence of 32°F. night temperatures in both the spring and fall, making the growing degree accumulation unrealistic.Introduction and general comments -- Description of Stations -- Results and discussion -- Summary -- References -- Appendix -- Figures: Fig. 1 Average weekly growing degree units for Matanuska Experiment Station; Big Delta; University Experiment Station, Fairbanks; Homer; Kasilof; and Kodiak. Fig. 2 Seasonal growing degree unites (May 15 to 1st 30°F or lower temperature in fall) which will be equaled or exceeded for varying probability levels at Big Delta, Matanuska Experiment Station and University Experiment Station, Fairbanks. Fig. 3 Seasonal growing degree units (May 15 to 1st 30°F or lower temperature in fall) which will be equaled or exceeded for varying probability levels ta Homer, Kasilof, and Kodiak. Tables: Table 1 Comparison of growing-degree units (GDU) for Clearwater and Big Delta for the period 1965-70. Table 2 Highest, lowest and average weekly GDU values for Big Delta, and values which will be equaled or exceeded for given probabilities. Table 3 Highest, lowest and average weekly GDU values for Homer and values which will be equaled or exceeded for given probabilities. Table 4 Highest, lowest and average weekly GDU values for Kasilof and values which will be equaled or exceeded for given probabilities. Table 5 Highest, lowest and average weekly GDU values for Kodiak and values which will be equaled or exceeded for given probabilities. Highest, lowest and average weekly GDU values for the Matanuska Experiment Station, and values which will be equaled or exceeded for given probabilities. Table 7 Highest, lowest and average weekly GDU values for the University Experiment Station, Fairbanks and values which will be equaled or exceeded for given probabilities at 6 Alaska locations. Table 8 Highest, lowest and average monthly GDU values and values which will be equaled or exceeded for given probabilities at 6 Alaska locations. Table 9 Highest, lowest and average seasonal GDU values and values which will be equaled or exceeded for given probabilities for the period May 15 to date of first 30°F or lower temperature in the fall at 6 Alaska locations

Rotorcraft technology at Boeing Vertol: Recent advances

An overview is presented of key accomplishments in the rotorcraft development at Boeing Vertol. Projects of particular significance: high speed rotor development and the Model 360 Advanced Technology Helicopter. Areas addressed in the overview are: advanced rotors with reduced noise and vibration, 3-D aerodynamic modeling, flight control and avionics, active control, automated diagnostics and prognostics, composite structures, and drive systems

The work of community gardens: reclaiming place for community in the city

The growth of community gardens has become the source of much academic debate regarding their role in community empowerment in the contemporary city. In this article, we focus upon the work being done in community gardens, using gardening in Glasgow as a case study. We argue that while community gardening cannot be divorced from more regressive underlying economic and social processes accompanying neoliberal austerity policies, it does provide space for important forms of work that address social needs and advance community empowerment. In developing this argument we use recent geographical scholarship concerning the generative role of place in bringing together individuals and communities in new collective forms of working. Community gardens are places that facilitate the recovery of individual agency, construction of new forms of knowledge and participation, and renewal of reflexive and proactive communities that provide broader lessons for building more progressive forms of work in cities

The NASA aircraft icing research program

The objective of the NASA aircraft icing research program is to develop and make available to industry icing technology to support the needs and requirements for all-weather aircraft designs. Research is being done for both fixed wing and rotary wing applications. The NASA program emphasizes technology development in two areas, advanced ice protection concepts and icing simulation. Reviewed here are the computer code development/validation, icing wind tunnel testing, and icing flight testing efforts

Engine technology challenges for a 21st Century High-Speed Civil Transport

Ongoing NASA-funded studies by Boeing, McDonnell-Douglas, General Electric, and Pratt & Whitney indicate that an opportunity exists for a 21st Century High-Speed Civil Transport (HSCT) to become a major part of the international air transportation system. However, before industry will consider an HSCT product launch and an investment estimated to be over $15 billion for design and certification, major technology advances must be made. An overview of the propulsion-specific technology advances that must be in hand before an HSCT product launch could be considered is presented

Metathetical reactions of methoxyl radicals

The chemistry of methoxyl has been reviewed with emphasis placed on quantitative experiments. The following reactions have been discussed: radical production, combination, disproportionation and hydrogen abstraction. There is very little quantitative information available on the metathetical reactions of methoxyl radicals, and in particular no previous studies of hydrogen abstraction from C2 to C5 alkanes has been reported for methoxyl or any other alkoxyl radical. Three approaches to the study of the metathetical reactions of methoxyl have been described. The first two methods, which depended on measuring the rate of formation of products, had to be abandoned because analysis showed that the systems were more complex than previous work had indicated. The third and apparently successful approach depended on measuring consumption of reactants when methoxyls were generated in mixtures of alkanes between 200 °C and 400°C: CH3O + R1H = CH3OH + R1 CH3O + R2H = CH30H + R2 The alkyl radicals were removed by nitric oxide. The experiments were oerformed in a cyclic flow system and the residual alkanes were estimated by the Janak technique of gas chromatography

Controlling Darkness: Self, Dark and the Domestic Night

Social science research into darkness (and light) has largely focused on public spaces. In particular it has been interested in night-time cityscapes, but also spaces of leisure and rural landscapes. This paper instead turns its eye towards the more private experiences of darkness in the home. In this paper I look to explore the active role that darkness plays in constituting our relation to the home, arguing that it takes on a central role. Drawing on phenomenological arguments about experience of dark, I argue that in darkness the self is rendered more open to the other. The ability to choose the conditions in which this openness to the other is experienced becomes important: where power over this choice exists, openness can be experienced as conviviality or intimacy; where power is absent, this openness is more likely to be experienced as vulnerability. As such, controlling darkness in the home is an act of power. This argument is then explored through a study of various trends in geography and social science research into the home, focusing on how the home can slide between poles of security and protection, and insecurity and danger. Though speculative, this paper seeks to set out new ground for research, and new understandings for existing knowledge about darkness and the home

Single-particle entanglement and three forms of ambiguity

This paper discusses experiments with single-particle systems, some of whose states appear to be entangled. It shows that the interpretation of the experiments in terms of entanglement is ill defined. Three forms of ambiguity are discussed. The choice of state-space and its dimensions is a matter of taste. There is not an a-priori natural partitioning of the state-space. The observables are not necessarily experimentally accessible and only determined by theory-laden extrapolation from experimental results. These ambiguities need to be addressed in the formulation of any general theory of entanglement

Effects of an electrolyte on the activities of water and alcohol in mixtures

(1) An air-bubbling method has been devised for the determination of the partial pressures of water and alcohol in mixtures, in which the volume of air required is less than a litre.(2) The partial vapour pressures of water and alcohol have been measured at 25°C, in mixtures containing no solute and in mixtures containing lithium chloride at concentrations of o. 5 m, 1.0 and 4.0 m. Similar measurements have been made at 35°0. with a concentration of 1.0 m and also with no solute.(3) It has been shown that, in water.alcohol mixtures, lithium chloride lowers the activity of water, while it may either lower or raise that of alcohol, depending on the composition of the solvent and the concentration of lithium chloride. The fractional lowering, in the case of water, is always greater than that in the case of alcohol.(4) An approximately linear relation has been established between the relative activities of both water and alcohol, and the molar fraction of alcohol in the solvent.(5) The latent heats of evaporation of water and alcohol in mixtures containing no electrolyte, and in mixtures with lithium chloride at a concentration of 1.0 m as solute,have been calculated, but these results do not appear to be very significant