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1.
基于卷积神经网络的田间多簇猕猴桃图像识别方法   总被引:21,自引:17,他引:4  
为实现田间条件下快速、准确地识别多簇猕猴桃果实,该文根据猕猴桃的棚架式栽培模式,采用竖直向上获取果实图像的拍摄方式,提出一种基于Le Net卷积神经网络的深度学习模型进行多簇猕猴桃果实图像的识别方法。该文构建的卷积神经网络通过批量归一化方法,以Re LU为激活函数,Max-pooling为下采样方法,并采用Softmax回归分类器,对卷积神经网络结构进行优化。通过对100幅田间多簇猕猴桃图像的识别,试验结果表明:该识别方法对遮挡果实、重叠果实、相邻果实和独立果实的识别率分别为78.97%、83.11%、91.01%和94.78%。通过与5种现有算法进行对比试验,该文算法相对相同环境下的识别方法提高了5.73个百分点,且识别速度达到了0.27 s/个,识别速度较其他算法速度最快。证明了该文算法对田间猕猴桃图像具有较高的识别率和实时性,表明卷积神经网络在田间果实识别方面具有良好的应用前景。  相似文献   
2.
Soil erosion is a major land degradation problem in South Africa (SA) that has economic, social and environmental implications due to both on-site and off-site effects. High rates of soil erosion by water are causing rapid sedimentation of water bodies, ultimately leading to water crisis in SA. Lots of financial and human resources are channelled towards controlling of soil erosion but unfortunately with little success. The level of soil erosion in a particular area is governed by the site properties. Therefore, it is inappropriate to generalize data on soil erosion at a large-scale spatial context. The literature on soil erosion in SA classifies Eastern Cape Province as a high-erosion-potential area using data collected at a large-scale spatial context. Collecting soil erosion data at a large spatial scale ignores site-specific properties that could influence soil erosion and has resulted in failure of many traditional soil erosion control measures applied in the province. Moreover, scientific principles underlying the processes and mechanisms of soil erosion in highly erodible soils are missing in SA. This review was to find effective soil erosion control measures by having an insight on what happens during soil erosion and how soil erosion occurs in Ntabelanga. The literature suggested that erosion in Ntabelanga could be influenced by both the erosivity and erodibility factors though the erodibility factors being more influential. Soil permeability contrast between the horizons could be influencing the rate and nature of soil erosion. To mitigate the impact of soil erosion in Ntabelanga, efforts should aim to improve the vertical flow capacity in the B horizon. Clay spreading, clay delving, addition of gypsum, deep ploughing and mulching could aid the water permeability problems of the subsurface horizons. However for effective soil management and control option, detailed studies of specific site properties are needed. The generated information can assist in formulating soil erosion policies and erosion control strategies in the Ntabelanga area and SA at large.  相似文献   
3.
The prevalence of claw disorders is still high among cows housed on concrete floors. Concrete floors affect the locomotion of cattle, their natural behavior. Although many factors affect the development of claw disorders and locomotor problems, biomechanical aspects have hardly been analysed. In this thesis, mechanical (over)loading of the claw and its significance for claw disorders and lameness are discussed. The mechanical characteristics a floor needs to provide in order to enable unrestrained locomotory behavior. This biomechanical approach, which is a relatively new approach in cattle locomotion, has provided new insights. Despite preventive trimming, the weakest parts of the claw capsule are loaded relatively the most. Concrete floors provide too little friction to enable unrestricted cattle locomotion.  相似文献   
4.
Soil erosion has serious off-site impacts caused by increased mobilization of sediment and delivery to water bodies causing siltation and pollution. To evaluate factors influencing soil erodibility at a proposed dam site, 21 soil samples collected were characterized. The soils were analyzed for soil organic carbon (SOC), exchangeable bases, exchangeable acidity, pH, electrical conductivities, mean weight diameter and soil particles’ size distribution. Cation exchange capacity, exchangeable sodium percentage, sodium adsorption ratio, dispersion ratio (DR), clay flocculation index (CFI), clay dispersion ratio (CDR) and Ca:Mg ratio were then calculated. Soil erodibility (K-factor) estimates were determined using SOC content and surface soil properties. Soil loss rates by splashing were determined under rainfall simulations at 360?mmh?1 rainfall intensity. Soil loss was correlated to the measured chemical and physical soil properties. There were variations in soil form properties and erodibility indices showing influence on soil loss. The average soil erodibility and SOC values were 0.0734?t?MJ?1?mm?1 and 0.81%, respectively. SOC decreased with depth and soil loss increased with a decrease in SOC content. SOC significantly influenced soil loss, CDR, CFI and DR (P??1. Addition of organic matter stabilize the soils against erosion.  相似文献   
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6.
This study was in an olive (Olea europea L.) grove in the Vélez Blanco District of Almería, Spain, where the soil is a typical Aridisol. The aim was to evaluate subsoil compaction caused by three different tractors currently used in olive groves. Measurements were made of (i) the cone index (CI), (ii) hydraulic conductivity (HC) and (iii) rut depth after passage of a light tractor (LT = 22.50 kN), a heavy tractor (HT = 42.60 kN) and a medium tractor (MT = 33.30 kN). The CI differed for the topsoil (0–200 mm) for each type of tractor after up to five passes. In this depth soil level, the CI was greatest for LT because the ground pressure (by narrow tyres) was greater than under the MT and HT. For deeper layers, there was a strong positive relationship between number of tractor passes and CI values, and the CI was greater for passes by the HT than the LT or MT. The HT resulted in shallower ruts up to the fifth pass, and the CI values were smaller because there was less ground pressure from this tractor than the others. In all treatments, tractor traffic caused varying decreases in HC in the 0–600 mm depth range. The main conclusion is that subsoil compaction is related directly to tractor weight. For the three tractors, topsoil compaction is caused by ground pressure and not on total axle load.  相似文献   
7.
A study was carried out to compare the influence of four Guinea grass ecotypes (Panicum maximum) differing in their morphological, physiological, and agronomical traits on soil fertility in Soudanian region of West Africa. Plants were sown in a randomized complete block design with four replicates and cultivated during three successive years under a cut-and-carry regime without any fertiliser use. A natural fallow served as the control. Soil samples were collected before and after cultivation, and analyzed for pH, organic carbon, nitrogen, available P, and exchangeable cation contents. Aerial plant production was quantified and analyzed for N, P, and K content to estimate the uptake of these nutrients. Root biomass, depth, and distribution were also measured. Data were analyzed through ANOVA. After 3 years of cultivation, soil pH under plants did not vary but C and N concentrations declined from the initial levels. Owing to their deep rooting systems, two ecotypes can recycle nutrients apparently from deeper soil layers. While these ecotypes could be used for ley pastures in savannah regions of West Africa, maintenance fertiliser applications would be required to prevent nutrient depletion under a cut-and-carry regime. Further studies to test the efficacy of farmyard manure in providing these nutrients seem warranted.  相似文献   
8.
Both Bos indicus (zebu) and Bos javanicus (banteng) contribute to the Indonesian indigenous livestock, which is supposedly of a mixed species origin, not by direct breeding but by secondary cross-breeding. Here, the analysis of mitochondrial, Y-chromosomal and microsatellite DNA showed banteng introgression of 10-16% in Indonesian zebu breeds with East-Javanese Madura and Galekan cattle having higher levels of autosomal banteng introgression (20-30%) and combine a zebu paternal lineage with a predominant (Madura) or even complete (Galekan) maternal banteng origin. Two Madura bulls carried taurine Y-chromosomal haplotypes, presumably of French Limousin origin. There was no evidence for zebu introgression in five populations of the Bali cattle, a domestic form of the banteng.  相似文献   
9.
The red bud borer Resseliella oculiperda (Rübs.) is a pest insect of apple trees when rootstocks are grafted with scion buds by 'shield budding'. The female midges are attracted to the wounds of the grafted buds where they lay their eggs. The larvae feed on the cambium and destroy the buds completely or partially, leading to bad union of the buds with the rootstocks. Budding strips are used very often by growers to bind scion buds to rootstocks. These strips cannot prevent midges from reaching the damaged tissue. Chemical treatments applied to the grafts and other types of strip do not provide better protection against the pest and may cause other risks for growers. In orchard experiments in 2000 and 2001, the authors evaluated the repellent action provided by three essential oils and five compounds of plant origin against the midges by impregnating budding strips with them. The essential oils of lavender, Lavandula angustifolia (P. Mill.), and alpha-terpineol decreased the infestation of buds by more than 95 and 80% respectively. The other potential repellents tested [the essential oil of Juniperus virginiana (L.), citronellal, the essential oil of Cinnamomum camphora (L.) J. Presl, R-carvone, linalool and R-fenchone] decreased infestation by 67, 66, 51, 45, 37 and 25% respectively. The formulation and commercial development of budding strips impregnated with lavender oil is discussed.  相似文献   
10.
Colorado beetles moved upwind in a wind tunnel. Odour from leaves of potato, nightshade, tomato and bittersweet enhanced the response. The response disappeared after four antennal segments had been amputated. The odour from meadow grass and dandelion repelled the beetles. Beetles 2–3 weeks emerged but not newly emerged beetles were slightly attracted by celerey. In the same wind tunnel, the scent of female beetles attracted males.Samenvatting In een windtunnel werden proeven gedaan over de reactie van Coloradokevers op de geur van diverse planten. In controleproeven werd een positief anemotactische reactie bij de kevers waargenomen, die werd versterkt door de geur van bladeren van aardappel, nachtschade, tomaat en bitterzoet. In beide gevallen verdween de anemotactische reactie na amputatie van 4 leden van de antennae. Gras en paardebloem beïnvloedden het anemotactisch effect in negatieve zin. Selderij bleek enigszins aantrekkelijk te zijn voor kevers van 2–3 weken oud. Met behulp van hetzelfde apparaat werd aangetoond dat de wijfjes een voor de mannetjes aantrekkelijke geur produceren.  相似文献   
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