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31.
Flexible exchange of farming device data 总被引:2,自引:0,他引:2
A new trend in the farming business is to replace conventional farming devices with computerized farming devices. Accordingly, numerous computer-based farming devices for logging, processing and exchanging data have recently been installed on moving farm machinery such as tractors. The exchange of data generally takes place between the devices and farming systems, mostly installed at the premises of farmers, contractors, advisory services, etc. In most cases, data exchange is based on farming data exchange standards and is bi-directional. Bi-directional data exchange allows different devices and systems to exchange data based on a predefined set of rules. In consequence, many hand-coded data exchange solutions have been developed in the farming business. Although efforts regarding incorporating data exchange standards have been made, their actual usage so far has been limited, due to the fact that hand-coded bi-directional data exchange solutions have proven themselves too complex to maintain. Maintenance need to occur as requirements change frequently and the existing data exchange techniques lack flexibility with regards to efficient requirements change management. In addition, requirements change results in managing low-level code rather than a high-level specifications. This paper presents a bi-directional data exchange solution in the farming business that is based on high-level specifications without any need for hand-coding. The proposed solution supports ISOBUS based bi-directional data exchange as well as efficient requirements change management through a graphical user interface. The paper also demonstrates the use of the proposed solution based on a farming case study and open source technologies. 相似文献
32.
Ted R. Turner Steven D. Duke Brian R. Fransen Maryanne L. Reiter Andrew J. Kroll Jim W. Ward Janette L. Bach Tiffany E. Justice Robert E. Bilby 《Forest Ecology and Management》2010
Elevated landslide rates in forested landscapes can adversely impact aquatic habitat and water quality and remove and/or degrade soil resources required for forest regeneration. As a result, understanding the associations between management actions, natural factors, and landslide rates is important information needed for land managers. An unusual and powerful storm in early December, 2007, caused record flooding and thousands of landslides across southwest Washington and northwest Oregon, USA, and provided a rare opportunity to examine the effects of both natural factors and forest management practices on landslide density. Landslide inventory data were collected from both aerial photos and systematic field surveys to provide a broad survey database that was used to develop estimates of landslide density and to examine associations between landslide density, precipitation, topography, and forest stand age across a 152,000 ha forested landscape in the Willapa Hills, Washington. We estimated the probability of detecting landslides on aerial photos for six strata defined by forest stand age and a broad range of rainfall intensity, expressed as percent of the 100-year, 24-h, maximum rainfall. Key findings are that landslide detection probability decreased with increasing stand age, but was similar across rainfall intensities. The overall fraction of field-detected landslides that were not detected on 1:12,000-scale aerial photos was 39%. Very few landslides occurred in the 0–100% of 100-year rainfall category, regardless of stand age or slope gradient class. At higher rainfall intensities, significantly higher landslide densities occurred on steep slopes (>70% gradient) compared to lower gradient slopes, as expected. Above ∼150% of 100-year rainfall, the density of landslides was ∼2–3 times larger in the 0–5 and 6–10 year stand age categories than in the 11–20, 21–30, 31–40, and 41+ categories. The effect of stand age was strongest at the highest rainfall intensities. Our results demonstrate that ground-based landslide inventory data are required in order to correct for detection bias from aerial photos, develop reasonable estimates of landslide density across environmental gradients such as rainfall magnitude and topography, and make unbiased interpretations of relationships between forest management associations and landslide occurrence. 相似文献
33.
Araújo FD Esper LM Kuaye AY Sircili MP Marsaioli AJ 《Journal of agricultural and food chemistry》2012,60(2):585-592
A chemical study of acyl-homoserine lactones (acyl-HSLs) produced by Enterobacter sakazakii resulted in the identification of three molecules: (S)-N-heptanoyl-HSL, (S)-N-dodecanoyl-HSL and (S)-N-tetradecanoyl-HSL. Mixed cultures of E. sakazakii and Bacillus cereus depleted E. sakazakii acyl-HSLs, suggesting acyl-HSL degradation by B. cereus hydrolases (hydrolysis of the lactone or amide moiety). The expression of B. cereus acyl-HSL lactonase and acyl-homoserine acylase was confirmed by monitoring the biotransformation of (S)-N-dodecanoyl-HSL into (S)-N-dodecanoyl-homoserine, dodecanoic acid and homoserine in the presence of B. cereus whole cells, using electrospray-mass spectrometry (ESI-MS). 相似文献
34.
Biodegradation measurements confirm the predictive value of the O:C‐ratio for biochar recalcitrance 下载免费PDF全文
Mo Bai Burkhard Wilske Franz Buegger Esben Wilson Bruun Martin Bach Hans‐Georg Frede Lutz Breuer 《植物养料与土壤学杂志》2014,177(4):633-637
Suitable predictors of degradability are sought to support the identification of biochars with large potential to increase C sequestration in soils. We determined the biodegradation of 9 chars from hydrothermal carbonization and pyrolysis in two agricultural soils. The 200‐ and 115‐day degradation correlated strongly with the O:C‐ and slightly with the H:C‐atomic ratio of 9 and 14 biochars, respectively. Highest temperature treatment and ash content did not show similar correlations. 相似文献
35.
Jocelyne Delisle Jean Amiot Germain-J. Brisson Monique Lacroix 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,33(2-3):173-177
Although the efficiency ratio (PER) of vegetable proteins can be improved by supplementation with the limiting free amino acids, the digestibility of these proteins remains lower than that of animal proteins. The digestibility of a rapeseed protein concentrate measured in rats was improved from a value of 81 to 87% by water solubilization and ammonium sulfate precipitation. 2S and 12S fractions were also prepared from a rapeseed protein concentrate by a method based on differences of solubility in ammonium sulfate solutions. Protein digestibility of the rapeseed protein concentrate was found to be 82%, as compared to 87% and 89% for 2S and 12S fractions. A reduction of protein efficiency ratio was also recorded and was found to result from losses in amino acids. 相似文献
36.
37.
Praemachiloides iberica n. sp. is described and compared with the other four known species of the genus: P. janetschecki, P. insularis, P.tarsispina and P. autumnalis. The main difference of P. iberica n. sp. from the other known congenerics is the presence, in the male, of a field of plaited setae on the ventral surface of the maxillary palp. 相似文献
38.
Keko Hori Maxima E. Flavier Shigenori Kuga Thi Bach Tuyet Lam Kenji Iiyama 《Journal of Wood Science》2000,46(5):401-404
The study focused on kapok [Ceiba pentandra (L.) Gaertn.] fruit as a biomass for effective utilization. Kapok fruits were harvested just before full maturation at the campus of University of the Philippines Los Banos and in southern Vietnam. The kapok fibers are utilized locally as fiberfill in pillows, quilts, and some soft toys. Kapok fiber was isolated and analyzed microscopically, and the physicochemical properties were determined by spectroscopic methods. Some tests were done to determine the effective utilization of kapok fiber. Microscopic analysis of the higher structure of kapok fiber gave quite different results from cotton fiber, which has a significantly homogeneous hollow tube shape and is composed of cellulose (35 % dry fiber), xylan (22%), and lignin (21.5%). Kapok fiber is characterized by having a high level of acetyl groups (13.0%). Usually cell walls of plants contain about 1%–2% of acetyl groups attached to noncellulosic polysaccharides. Kapok fiber is significantly hydrophobic and does not get wet with water. Thus, the absorptivity of oil was tested. The fiber selectively absorbed significant amounts of oil (40 g/g of fiber) from an oil suspension in freshwater and seawater. It is suggested that this fiber could be used to recover oil spilled in seawater. 相似文献
39.
Hematologic and biochemical reference intervals for Wild Boar (Sus scrofa) captured by cage trap 下载免费PDF全文
40.
H J?rgensen X Q Zhao P K Theil V M Gabert K E Bach Knudsen 《Archives of Animal Nutrition》2003,57(2):83-98
A study was performed to investigate the effect of different levels of dietary fibre (DF) and dietary protein on visceral organ size, digestibility, nitrogen balance and energy metabolism in rats. Thirty-six male Wistar rats, initial body weight about 76 g were used in a factorial design consisting of three levels of DF (low, 100 g/kg DM: medium, 250 g/kg DM and high, 290 g/kg DM) and two levels of dietary protein (low, 120 g/kg DM and high, 223 g/kg DM). The added fibre source was soybean hulls and Danish fish meal was used as sole source of dietary protein. Measurements of gas-exchange were done on six rats (one group) while urine and faeces were collected individually. The ratio of food/empty body gain increased (P<0.05) with increasing DF and decreasing levels of dietary protein. The weight of the digestive tract was larger (P<0.05) in rats fed the high fibre diet than in those fed the low fibre diet. The digestibility of nutrients and energy decreased linearly with increasing level of soybean fibre (P<0.05). An increased intake of DF was associated with a concomitant loss of protein and energy to faeces. The microbial degradation of NSP and other unabsorbed carbohydrates caused considerably changes in N metabolism of the colon. In rats fed the low protein diets increased levels of DF decreased N excretion in urine and increased N excretion in faeces, while the ratio of retained/digested protein remained constant. When rats were fed the high protein diet protein retention dropped in response to DF both absolute and relative to digested amount, indicating that energy intake could be a limiting factor. Heat production as a percentage of metabolizable energy (HP/ME) was higher (P<0.05) in rats fed the low protein diet than in rats fed the high protein diet, but no significant difference was found among DF levels. 相似文献