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11.
Crop disease has a negative impact on food security. If diverse crop diseases are not identified in time, they can spread and influence the quality, quantity, and production of grain. Severe crop diseases can even result in complete failure of the harvest. Recent developments in deep learning, particularly convolutional neural networks (CNNs), have exhibited impressive performance in both image recognition and classification. In this study, we propose a novel network architecture, namely Mobile-DANet, to identify maize crop diseases. Based on DenseNet, we retained the structure of the transition layers and used the depthwise separable convolution in dense blocks instead of the traditional convolution layers, and then embedded the attention module to learn the importance of interchannel relationship and spatial points for input features. In addition, transfer learning was used in model training. By this means, we improved the accuracy of the model while saving more computational power than deep CNNs. This model achieved an average accuracy of 98.50% on the open maize data set, and even with complicated backdrop conditions, Mobile-DANet realized an average accuracy of 95.86% for identifying maize crop diseases on a local data set. The experimental findings show the effectiveness and feasibility of the Mobile-DANet. Our data set is available at https://github.com/xtu502/maize-disease-identification .  相似文献   
12.

A survey of 7122 dromedary camels in 115 herds in Saudi Arabia was used to estimate the effects of herd size (HZ; <?25 vs. 25–49 vs. 50–100 vs. >?100 camels), herder/camels ratio (H/C; 1:<?25 vs. 1:25–50 vs. 1:>?50), manager experience (ME; <?5 vs. 5–10 vs. >?10 years), male/females ratio (M/F), housing system (HS; free vs. closed vs. mixed), length of the breeding season (winter vs. winter and spring vs. fall, winter and spring), age at first mating (3 vs. >?3 years), and time of mating after parturition (≤?3 vs. >?3 months) and their interactions on the overall pregnancy rate. Barren females of these herds (n?=?886) were examined for the causes of infertility. Results showed that herds with H/C of 1:<?25 had higher overall pregnancy rate (95.29%) than herds with H/C of 1:25–50 (79.84%) and those with H/C of 1:>?50 (72.79%) (p?=?0.003). Herds having ME of >?10 years revealed greater overall pregnancy rate (94.89%) than herds with ME of 5–10 years (80.54%) and those with ME of <?5 years (72.5%) (p?=?0.001). There were significant interactions between H/C × HZ (p?=?0.003), H/C × HS (p?=?0.006), and ME × HS (p?=?0.02). The overall pregnancy rate did not significantly differ between herds bred females by age of 3 years and those bred females by age >?3 years and in females bred within 3 months after parturition and in those bred after 3 months. The mean calving interval was shorter (p?=?0.008) in camels mated within 3 months of parturition (15.25?±?2.8 months) than in those mated after that time (24.33?±?6.5 months). Clinical endometritis, ovarian hydrobursitis, and vaginal adhesions were the common clinical findings in barren females. Thus, efforts to reduce the age at first mating and the interval after calving, increase the number of herders/camels, and control reproductive disorders could improve the reproductive performance and quality of camel herds in Saudi Arabia.

  相似文献   
13.
Plant growth, nutritional status, and proline content were investigated in non-grafted and grafted greenhouse tomato plants onto five rootstocks of eggplant, datura, orange nightshade, local Iranian tobacco, and field tomato, exposed to 0, 5, and 10 mM sodium bicarbonate (NaHCO3) to determine whether grafting could improve alkalinity tolerance of tomato. The leaf fresh mass of ungrafted and grafted tomato plants decreased significantly as NaHCO3 levels increased. Despite other rootstocks and ungrafted plants, alkalinity had no significant effect on stem and root fresh mass and shoot phosphorus (P), potassium (K) and magnesium (Mg) concentrations of datura grafted plants. The lowest solution pH and electrical conductivity (EC) values and the highest leaf proline content were observed in the plants grafted onto datura rootstock. Moreover, sodium (Na) concentration in shoots was lower in plants grafted onto datura rootstock than in other plants especially under high NaHCO3 levels. Overall, using datura rootstock improved alkalinity tolerance of tomato plants under NaHCO3 stress.  相似文献   
14.
15.
A rhizobox experiment was conducted to study the effects of alfalfa green manure (GM) and the culture system on the dry matter yield and metal uptake in corn (Zea mays) and canola (Brassica napus) grown in rhizobox systems containing a metal-rich agricultural soil. The results showed that GM application increased soil organic matter (SOM), dissolved organic carbon (DOC), and electrical conductivity (EC) by 41%, 82%, and 35%, respectively, while the soil pH decreased by ~0.3 units. These changes were associated with enhanced soil bioavailability of Zn (14%), Cu (26%), and Ni (20%) and improved shoot dry matter yield of the plants. Soil metal bioavailability was also found to be enhanced due to the presence of plant roots. Canola intercropped with corn produced greater individual plant dry weights (IPDWs) of 96% and 59% in the untreated and GM-amended rhizoboxes, respectively. The intercropped corn, however, recorded 25% and 6.4% lower IPDW values in unamended and GM-amended soils, respectively, as compared to the monocropped corn. Enhanced Zn, Cu, and Ni uptakes were observed in canola shoots, while they decreased in corn shoots. The results demonstrate the importance of organic amendment and intercropping strategies for managing metal uptake by plants grown in metal-rich soils.  相似文献   
16.
Two shortcomings of the non-numeric United States Soil Laboratory (USSL) water quality designation process are, first, the uncertainty involved with assigning samples to the bordering discrete classes is not considered and, secondly, it is difficult to map. One solution to these may lie in the use of a Mamdani fuzzy inference system (MFIS). The main aims of this study were (1) to compare the MFIS and USSL approach to classifying groundwater quality for irrigation and (2) to explore the spatial variability of groundwater quality for irrigation in the Marvdasht aquifer using the MFIS output. For this purpose, 49 agricultural wells were sampled and their sodium adsorption ratio and electrical conductivity were determined. In 81% of cases, the MFIS led to the same class as USSL and in 92.8% of cases agreed with USSL classification. In only 2 out of 49 samples did the MFIS and USSL strongly disagree. The comparison showed that the MFIS method is more acceptable, reliable, and logical in the classification of water quality for irrigation purposes than other methods. The output map of the MFIS scores indicates that the upper part of Marvdasht aquifer has better quality water for irrigation.  相似文献   
17.
It has been shown that pomegranate fruit powder (PFP) has the potential to decrease urea-nitrogen (N) mineralization and improve grain yield of maize, but the mechanisms of this effect are not fully understood. Therefore, the objective of this study was to investigate these mechanisms. For this purpose, an incubation and a pot experiment were conducted, in which four levels of PFP coating equivalent to 0%, 30%, 70%, and 100% (w/w) of urea were studied. PFP had very little effect on nitrification (1.4–2.9%). Mineral N and nitrite (NO2?)–N decreased (23% and 38%, respectively) with increasing PFP application, probably due to N-immobilization or urea hydrolysis inhibition. Biomass and grain yield of maize increased with increasing phosphorus (P)/N ratio of leaf and stem, and decreasing P/N ratio of grain, indicating soil-P-mobilization and soil-N-immobilization during vegetative growth and the inverse, during grain filling by PFP. According to these results, PFP can be introduced as an urea-N immobilizer and soil-P mobilizer.  相似文献   
18.
Using pedotransfer functions (PTF) is a useful way for field capacity (FC) and permanent wilting point (PWP) prediction. The aim of this study was to model PTF to estimate FC and PWP using regression tree (RT) and stepwise multiple linear regressions (SMLR). For this purpose, 165 and 45 soil samples from UNSODA and HYPRES datasets were used for development and validation of new PTFs, respectively. %Clay, geometric mean diameter (dg), and bulk density (BD) were selected as predictor variables due to the highest correlation and lowest multicollinearity. The results showed that clay percentage with W* = 0.89 and dg with W* = ?0.57 were the most effective variables to predict PWP and FC, respectively. The RT method had a better performance (R2 = 0.80, ME = ?0.002 cm3cm?3, RMSE = 0.05 cm3cm?3 for FC and R2 = 0.85, ME = 0.003 cm3cm?3, RMSE = 0.03 cm3 cm?3 for PWP) than SMLR in estimation of FC and PWP.  相似文献   
19.
The purpose of this study is to synthesize grafted Bacterial Cellulose (BC) nanofibers using Atom Transfer Radical Polymerization (ATRP) reinforced into poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel matrix. Nanofibers grafting polymerizations were conducted in the presence of the catalyst CuCl/CuBr and the initiator 2-bromoisobutyrylbromide (2-BiBr). Degrees of substitution (DS) of BC-macroinitiators were quantified using both elemental analysis and gravimetric method. FTIR results confirmed BC nanofibers’ surface modifications of both initiator and hydroxyethyl methacrylate (HEMA) grafts. X-ray spectroscopy further confirmed the increase in carbonyl content after PHEMA-grafting polymerization. Results of the gravimetric analysis showed an increase in the weight of the grafted BC upon increasing reaction time. Furthermore, the change in the swelling ratio percentages of the reinforced composites product (BC-MI-3-g-PHEMA-1.5) was considerably higher based on reaction time. Slight increase in the swelling ratio of BC-MI-3 nanofibers was observed after 48 hours to reach 31 %. Moreover, results of thermal gravimetric analysis (TGA) demonstrated that decomposition temperature at 50 % weight loss (T50) decreased to 350 °C for BC-MI-3-g-PHEMA-1.5. These characteristics demonstrate potentials for applications in the biomedical fields including drug delivery and wound care.  相似文献   
20.
Tropical Animal Health and Production - Turkey coryza is a major respiratory disease caused by Bordetella avium (B. avium). It occurs in all ages of turkeys and is characterized by high morbidity...  相似文献   
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