68,268 research outputs found

    FLEXIBILITY IN AGRICULTURE

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    This paper considers the determinants of two dimensions of flexibility, the flexibility in adjusting aggregate output over time ("tactical flexibility") as well as the ability to switch quickly between products ("operational flexibility"). Econometric analysis of a sample of 40,000 farms in Upper-Austria for the period 1980 to 1990 suggests that larger full-time farms operated by younger, better educated farm operators are more flexible, ceteris paribus. The results further indicate a significant and negative interrelationship between tactical and operational flexibility.Farm Management, Industrial Organization,

    Characterization of solar cells for space applications. Volume 3: Electrical characteristics of OCLI hybrid MLAR solar cells as a function of intensity and temperature

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    Electrical characteristics of hybrid multilayer antireflectance coated silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature

    Development, Survival and Phenology of the Sweetclover Weevil Parasitoid, \u3ci\u3ePygostolus Falcatus\u3c/i\u3e (Hymenoptera: Braconidae)

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    Biennial sweetclovers were widely used for soil improvement and as for- ages in the first half of the 1900s. The introduction of the sweetclover weevil, Sitona cylindricollis, caused a drastic decline in sweetclover acreage. In North Dakota, yellow sweetclover, Melilotus officinalis, is still the legume of choice on organic farms. In an effort to control the weevil, the thelyotokous parasitoid Pygostolus falcatus was imported. Parasitoids were studied for temperature-dependent development, and adult longevity as influenced by temperature and availability of provisions. Development from egg to adult at 15, 20, 25 and 30°C was 58, 28, 22 and 21 d, respectively. No parasitoids were reared out at 10°C, although diapausing first instars were present. Longevity of adult parasitoids provided honey, water, sweetclover and sweet- clover weevils at 15, 20, 25 and 30°C was 29, 22, 12 and 6 d, respectively. Adults provided the following combinations of provisions at 25°C survived for: nothing-2 d; water-2 d; honey-4 d; honey and water - 6 d; honey, water and sweetclover - 11 d; honey, water, sweetclover and hosts - 12 d. Field cage releases and a degree-day model developed for the parasitoid demonstrated that poor synchrony between P. falcatus and the sweetclover weevil hinders its usefulness as a biological control agent

    Determinants and Dynamics of Farm Diversification

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    This paper examines the impact of various farm and household characteristics (such as farm size, the off-farm employment status, the farm operator's age and schooling and the number of family members) on the level as well as the dynamics of on-farm diversification. Using linked census data for Upper-Austria from 1980, 1985 and 1990 we provide evidence that smaller farms are more specialised and also tend to increase the degree of specialisation over time more quickly than large farms. A significantly lower degree of diversification (higher degree of specialisation) as well as a stronger reduction in diversification over time is also reported for businesses operated by older, less educated, part-time farm operators. The analysis of diversification dynamics also suggests that (a) farms adjust to changes in their environment by steadily approaching their long-run equilibrium level of diversification ( B-convergence), and (b) the variance of the diversification distribution declines over time ( O-convergence).Diversification, Farm Sector, Dynamics, Panel Data, Farm Management,

    Astronomy in the region 1-0.1mm wavelengths

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    Measurements in five different passbands in the spectral region below 20/cm were made with a liquid helium-cooled radiometer in two flights at approximately 40 km altitude. The equivalent temperatures are given for passbands of 1 to 5.4, 7.8, 7.9, 11.1, and 18.5/cm. The results are consistent with a 2.7 K thermal radiation background. Atmospheric radiation of uncertain magnitude dominates the region above 11/cm

    Characterization of solar cells for space applications. Volume 4: Electrical characteristics of Spectrolab BSF 200-micron Helios cells as a function of intensity and temperature

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    Electrical characteristics of Spectrolab BSF 200 micron Helios N/P silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature
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