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211.
Karl Gößwald 《Forstwissenschaftliches Centralblatt》1941,63(6):139-143
Ohne Zusammenfassung 相似文献
212.
Karl Marimittan Müller 《Forstwissenschaftliches Centralblatt》1928,50(5):149-162
Ohne Zusammenfassung 相似文献
213.
Dr. Karl Böning 《Journal of pest science》1928,4(1):8-10
Ohne Zusammenfassung 相似文献
214.
X-ray computed tomography (CT) is an imaging tool that is becoming increasingly available for use in veterinary medicine. Advantages, including depiction of detailed cross-sectional anatomy, improved contrast resolution, and computer reformatting, make it a potentially valuable diagnostic technique. Veterinary application of CT has been primarily limited to use in small animals. Current reports describe the technique for use in the horse, but there are no published studies correlating serial CT images with equine cross-sectional anatomy. A study of the distal extremity of the horse was undertaken to facilitate interpretation of images produced using CT. Transverse CT images of the distal forelimb of equine cadavers were evaluated relative to gross anatomic dissection. Resolution of bone architecture in transverse plane images was satisfactory, but soft-tissue' resolution, although satisfactory for visualization of major structures, was relatively poor, probably due to lack of interposed fat and insufficient differences in physical density and atomic number. Thus it appears in the equine distal limb that CT may be most useful for evaluation of complex bone abnormalities. 相似文献
215.
Karl Friederichs 《Journal of pest science》1942,18(9):97-98
Ohne Zusammenfassung 相似文献
216.
Karl Hefele 《Forstwissenschaftliches Centralblatt》1896,18(6):293-345
Ohne Zusammenfassung 相似文献
217.
Global Positioning System (GPS) tracking devices are a fundamental technology for quantifying the distribution and movement of livestock across landscapes. Although costs of GPS devices have decreased, it is still cost prohibitive to implement a large number of collars per study. Our objective was to develop and test a low-cost GPS collar using commercial off-the-shelf (COTS) electronic components to study livestock distribution and movement. Our COTS GPS tracker was built using the popular Arduino open-source microcontroller and a low-power timer board to cycle a GPS at defined intervals. Location data were saved to a data card in an open format for easy analysis. Total cost per COTS GPS device (including housing and collar) was $54.78. Average displacement from a known location and 95% circular error probability was 4.58 m, commensurate with other GPS collars. We tested durability and field performance of 25 COTS GPS collars against 24 existing GPS collars recording data at 5-min intervals in a southwest Idaho, United States study area. Our COTS GPS design and test showed that it is possible to manufacture low-cost location tracking devices, but the limitations of such devices must be considered relative to study objectives and duration. Low-cost location trackers will encourage collection of a higher density of location information to better understand patterns of livestock use in rangeland landscapes. 相似文献
218.
219.
Nourrddine Chafik Mohammed Mansour Btissam Elamrani Karl‐Werner Schramm Antonius Kettrup M Khalid Elamrani 《Pest management science》2001,57(6):527-530
The photochemical fate of the herbicide triflusulfuron‐methyl in aqueous solution under UV light (λ > 290 nm) was investigated. Nine photoproducts were detected and tentatively identified by LC/MS and LC/MS/MS analysis. The main routes of degradation involve the cleavage and/or contraction of the sulfonylurea bridge with the elimination of sulfur dioxide, which increases the acidity of the reaction medium. On the basis of the results obtained a photodegradation pathway is proposed. © 2001 Society of Chemical Industry 相似文献
220.
Baozhong Duan William G. Yendol Karl Mierzejewski Richard Reardon 《Pest management science》1992,36(1):19-26
Experimental evaluation of the computerized aerial spray prediction program (AGDISP) was conducted. Spray was applied over a flat site with a fixed-wing aircraft. Spray droplets were collected on flat cards 15 cm above the ground. Aircraft parameters were recorded during the trials. Deposits were analyzed with image analysis equipment to establish droplet-size spectra. A set of statistical parameters was applied to the measured and model-predicted droplet deposition. The results indicate that the model can predict the average droplet density and volume deposition over seven spray runs within a factor of two of actual measurements. 相似文献