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1.
Although 97% of U.S. farms are “family-owned,” little research examines how gender and sexual relationships – inherent in familial dynamics – influence farmers’ practices and livelihoods. Gender and sexual dynamics – shaped by race and class – affect who is considered a farmer, land management decisions, and access to resources like land, subsidies, and knowledge. We use feminist and queer lenses to illuminate how today’s agricultural gender and sexual relations are not “natural,” but when left uninterrogated are constructed in ways that harm women and queer farmers while limiting potential to develop sustainable practices. Women and queer farmers also resist, “re-orienting” gender and sexual relations in ways that expand possibilities for achieving food justice and ecological sustainability. We offer “relational agriculture” as a tool for making visible and re-orienting gender and sexual relations on farms. Relational agriculture brings sexuality into food justice and demonstrates the centrality of gender and sexuality to agricultural sustainability. 相似文献
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This paper presents real-time monitoring data and analysis results of the non-stationary vibrations of an operational wind turbine. The advanced time-frequency spectrum analysis reveals varied non-stationary vibrations with timevarying frequencies, which are correlated with certain system natural modes characterized by finite element analysis. Under the effects of strong wind load, the wind turbine system exhibits certain resonances due to blade passing excitations. The system also exhibits certain instabilities due to the coupling of the tower bending modes and blade flapwise mode with blade passing excitations under the variation of wind speed. An analytical model is used to elaborate the non-stationary and instability phenomena observed in experimental results. The properties of the nonlinear instabilities are evaluated by using Lyapunov exponent estimation. 相似文献
4.
Abstract Past theoretical investigations have reported that observed peaks in the diffusional growth of ice crystals in the vicinity of ‐5 and ‐15°C could be qualitatively modelled assuming certain specific crystal properties. This study re‐examines the ice crystal diffusional growth model using more recently available observations of pertinent crystal parameters. The results, indicative of the growth of average crystals, imply a much weaker dependence of the diffusional mass growth rate on temperature in the range of ‐5 to ‐15°C. Extension of the model to include growth by accretion, also suggests that the mass of heavily rimed crystals is not very sensitive to the original crystal habit. The results of the calculations are compared with observed crystal sizes in cumulus clouds following seeding on three different days. The observations indicate that small crystals were continuously being produced as long as 15 min after seeding. In two cases, crystals much larger than those predicted by the model for any reasonable set of parameters suggest that crystal aggregation may have been occurring at a significant rate. 相似文献
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Understanding climate variability and change is essential for designing adaptation policies and strategies to deal with the impacts of climate change on the agricultural sector. This Paper aims at assessing climate variability/change, the perception of rural farmers on climate change and preferred adaptation strategies among the farmers in some selected farming communities in Nigeria. The study thus used both meteorology data and social survey, to examine variability/change in climate and factors determining the adaptation techniques adopts by rural farmers. The results show a relatively uniform temperatures and some seasonal variations in recent years (diurnal range of temperature is about 10 °C) but the rainfall shows much more seasonal variations. The rainfall has relatively undeviating trend from 1981 to 1996 but the trend appears to be upwards from the year 1997 to 2010. About 72.8% participants responded in the affirmative that climate is changing but there appears to be a significant relationship between the length of farming experiences and farmers’ perceptions of climate change adaptation techniques. Water-related (about 53%) and nutrient related (about 52%) technologies appear to have a high preference among the farmers. The major driver that determines farmers’ preference for climate change adaptation techniques is their incomes and experiences. 相似文献
7.
Elaine M. Sadler Russell D. Cannon Tom Mauch Paul J. Hancock David A. Wake Nic Ross Scott M. Croom Michael J. Drinkwater Alastair C. Edge Daniel Eisenstein rew M. Hopkins Helen M. Johnston Robert Nichol Kevin A. Pimbblet Roberto De Propris Isaac G. Roseboom Donald P. Schneider Tom Shanks 《Monthly notices of the Royal Astronomical Society》2007,381(1):211-227
8.
Russell Cannon Michael Drinkwater Alastair Edge Daniel Eisenstein Robert Nichol Phillip Outram Kevin Pimbblet Roberto De Propris Isaac Roseboom David Wake Paul Allen Joss Bland-Hawthorn Terry Bridges Daniel Carson Kuenley Chiu Matthew Colless Warrick Couch Scott Croom Simon Driver Stephen Fine Paul Hewett Jon Loveday Nicholas Ross Elaine M. Sadler Tom Shanks Robert Sharp J. Allyn Smith Chris Stoughton Peter Weilbacher Robert J. Brunner Avery Meiksin Donald P. Schneider 《Monthly notices of the Royal Astronomical Society》2006,372(1):425-442
9.
Maxwell A Boateng Xikui Wang 《东北亚地学研究》2006,9(1):30-39,48
This research paper analyses the grain-size characteristics of the Quaternary deposits at Xingshan near Siping, Jilin province in China by employing graphic measures to study the grain size distribution and its mode of transport and deposition. The Quaternary deposits at Xingshan lie unconformable on Cretaceous rocks made of siltstone, mudstone and sandstone. The average grain size is between 8.06 to 8.55Ф (0. 002 6 0. 003 7 mm). The Quaternary deposits at Xingshan mainly compose of very fine silt to clay. The compositions of the grade are clay 63 % and silt 37 %. The clay size components are weathered debris transported and deposited by flowing water from the SE highlands or hills to the low lying NW Xingshan plains whereas the silty components accumulated by aoelian process. The Quaternary deposits at Xingshan accumulated in the middle and late Pleistocene interglacial periods from (459.12 - 39.03 ) ka to (88.92 - 7.56 ) ka. The standard deviation ranged from 0.96 to 1.36%, indicating that the sediments are moderately to poorly sorted, Coefficient of skewness ranged from 0.16 - 0.31 with an average skewness of 0. 218, (Positively skewed towards fine). Kurtosis values (0.84- 1.05) from the grain size distribution and visual inspection of the frequency curves indicate platykurtic to mesokurtic curves and unimodal to bimodal grain-size distribution. The type of deposit formation is sand dune and the source is at a distal from its provenance. 相似文献
10.
根据多卫星高度计海面高数据推算南中国海及菲律宾海域重力异常(英文) 总被引:1,自引:0,他引:1
t Gravity anomalies on a2.5 ×2.5 arc-minute grid in a non-tidal system were derived over the South China and Philippine Seas from multi-satellite altimetry data. North and east components of deflections of the vertical were computed from altimeter-derived sea surface heights at crossover locations, and gridded onto a 2.5 × 2.5 arc-minute resolution grid. EGM96-derived components of deflections of the vertical and gravity anomalies gridded into 2.5 × 2.5 arc-minute resolutions were then used as reference global geopotential model quantities in a remove-restore procedure to implement the Inverse Vening Meinesz formula via the 1D-FFT technique to predict the gravity anomalies over the South China and Philippine Seas from the gridded altimeter-derived components of deflections of the vertical. Statistical comparisons between the altimeter-derived and the shipboard gravity anomalies showed that there is a root-mean-square agreement of 5.7 mgals between them. 相似文献