Exploring remotely sensed technologies for monitoring wheat potassium and phosphorus using field spectroscopy

Given the importance of potassium (K) and phosphorus (P) contents to wheat yield and grain quality, and the very little experience that has been gained on nutritional monitoring of other than nitrogen using remotely sensed technologies, a study was undertaken to explore the possibility of identifying these mineral stresses using spectral data. Canopy spectra and biophysical data were collected from commercial and experimental fields in India and Israel. Traditional and newly developed vegetation indices, together with Partial Least Squares (PLS) regression models, were calculated in order to predict potassium and phosphorus contents from the wheat canopy spectral data. Results show that the application of PLS and specific narrow bands vegetation indices reached significant levels of accuracy in the retrieval of K and P levels, in comparison to traditional broad band indices. Additionally, it was observed that a significant improvement is obtained when the mineral total content is considered instead of the relative content. Therefore it was suggested that the biomass should also be retrieved from the spectral data. Finally, as very different crop conditions were included in this study, it was possible to confirm that the level of accuracy in the retrieval of K and P levels is related to the quality and variability of the data used for calibrating the models.     

Characterisation of spatial patterns of regional paddy rice with time series remotely sensed data

Remote sensing has facilitated the identification of acreage and spatial distribution of field crops with obvious seasonal dynamics. The primary objective of this study is to identify the spatial patterns of double-season early rice, single-season middle rice and double-season late rice of Hunan Province and Yuanjiang City, China, in 2010, using two kinds of time series remotely sensed imagery: 8-day composite MODIS surface reflectance product data (MOD09A1) and HJ-1A/B satellite images with a 4-day revisit period. The available MODIS and HJ-1 CCD images of transplanting and heading stages were first assured in accordance with the schedules of local traditional paddy fields tillage. Based on the MOD09A1 data product, time series normalised difference vegetation index (NDVI) images were calculated and smoothed to remove the noise and the atmospheric effects. Second, the spatial distribution and planting acreage of three types of rice of Hunan Province were derived from combining the enhanced vegetation index and land surface water index according to the water background and variation characteristics of NDVI values at transplanting and heading stages. Conversely, a two-test procedure was used to finish the identification of paddy rice in Yuanjiang City using time series HJ-CCD imagery. The first test was to derive the potential rice pixels using the NDVI image (?NDVI) between heading and transplanting stages, and the second test was to remove the non-rice pixels using maximum likelihood supervised classification. The experimental results showed that three types of rice were mainly distributed along the Dongting Lake Basin in Hunan Province and the relative errors were ?10.99, 1.46 and ?5.87 %, respectively, while they were primarily planted in the northern plains of Dongting Lake in Yuanjiang City, where the relative errors were 12.1, 16.7 and 0.8 %, respectively. We conclude that transplanting and heading stages are the best phenological combinations for identifying paddy rice through remote sensing time series analysis, and this study can provide a basis for evaluating paddy rice yield on a large scale .     

黄淮地区小麦旗叶主要光合色素含量及光谱吸收

用丙酮提取后,用日产岛津UV-160分光光度计在4年间测定了黄淮区85个普通小麦品种(系)旗叶中的叶绿素含量。叶绿素a含量为2.444～2.871 mg/g鲜叶,均约2.753 mg/g鲜叶(σ=0.093,n=163,下同);叶绿素b含量为0.875～1.688 mg/g鲜叶,均约1.253 mg/g鲜叶(σ=0.149);叶绿素a+b为3.340～4.516 mg/g鲜叶,均约4.028 mg/g鲜叶(σ=0.231);b/a为0.355～0.588,均约0.453(σ=0.0795)。小麦旗叶离体叶绿素均在662～663 nm、431～455 nm及327～378 nm处出现吸收高峰。豫麦13的a+b含量最高,且其光吸收峰谱表现明显的倾母遗传趋势。     

Real-time observation and prediction of physical processes in a typhoon-affected lake

A nowcasting system integrating observations and a numerical model was developed to better understand the spatial distributions and temporal variations in the dynamics of a small, subtropical lake occasionally influenced by severe rainstorms. The nowcasting system was used to monitor real-time meteorological conditions and thermal structures, to provide spatial information on the thermal and flow dynamics from model predictions, and to compare the predictions with the observations. The system was also able to determine whether the instruments collecting field data were performing correctly using telemetry operations. The nowcasting system was initially operated in the spring of 2009 in Yuan-Yang Lake, Taiwan. Rainstorm-induced mixing occurred due to Typhoon Morakot during August 7–9, 2009. The mixing was observed by the instruments, and the spatial distributions and temporal variations during the mixing were successfully predicted by the three-dimensional hydrodynamic lake model. A quantitative comparison of the energy balances among the heat, wind, and water inflow inputs to the lake implied that the typhoon-induced mixing was primarily caused by strong winds. The model predictions showed that the lake experienced mixing and flooding (large amounts of inflow/outflow discharges), resulting in homogenous temperatures and flows that moved to the outlet of the lake.     

Processing conditions influencing the physical properties of French fried potatoes

Summary Achieving optimal colour and texture in French fries requires careful control of the unit operations that convert the raw potatoes into fries. The effects of variation in blanching, drying and finish frying conditions on puncture properties (peak force and peak deformation) and Hunterlab L (lightness) values of French fries were investigated. Fries blanched by low-temperature long-time (LTLT) conditions had larger peak force, peak deformation and L value than fries processed by standard conditions. High-temperature short-time (HTST) blanching increased lightness but decreased peak force and peak deformation. For drying, the colour and textural quality of French fries processed by standard conditions were better than those processed by the drying alternatives. For finish frying, LTLT conditions increased peak force whereas HTST conditions increased lightness. Therefore, a compromise has to be made in processing conditions to optimise both colour and textural quality. Even after finish frying, compositional differences within potato tubers influenced texture, both between and within French fries.     

Effects of recycling processes on physical, mechanical and degradation properties of PET yarns

Mechanical properties and the long-term degradation properties of the recycled PET yarns are typically lower than the virgin PET yarns due to the contaminants coming from non-PET bottles, labels and caps etc. For environmental reasons, recycling of post-consumer polyester bottles into textile fibers has become commercially attractive. We studied mechanical and chemical recycling processes and examined their effects on yarn properties such as tensile properties, thermal characteristics, hydrolysis and photo-degradation. It was found that the virgin and the chemical recycled yarns with sufficient purification show similar processability, physical and mechanical properties, and long-term degradation behavior. The results provide useful information on recycled PET yarns for processability and serviceability for the high-end use.     

Determination of fabric physical properties for the simulation of Cusick drapemeter

A fabric drape shape database has been prepared to find the optimum combination of fabric physical properties for simulating the appearance of an actual fabric. First, an objective and quantitative evaluation method for the traditional Cusick drape tester has been devised. Then a virtual drape tester has been developed using an implicit integration based drape simulation engine to generate a series of virtually draped fabric with various physical properties. Finally, a search algorithm has been developed to find the optimum property combination for target fabric by comparing the simulated results with the Cusick drape tester result of that fabric.     

Determination of total glycoalkaloids in potato tubers using a modified titration method

A new method for determining total glycoalkaloid content of potatoes (TGA) was developed by extensively modifying the comprehensive titration procedure of Fitzpatrick and Osman (1). This modified titration method eliminates the need to hydrolyze the glycoalkaloids and to purify the resulting aglycones by partitioning them into an organic solvent such as benzene or methylene chloride. Instead the glycoalkaloids are precipitated using ammonium hydroxide with the precipitate being dissolved in a tetrahydrofuran-water-acetonitrile (50:30:20) mixture. An aliquot is evaporated and quantitated using the nonaqueous titration procedure developed by Fitzpatrick and Osman (1). A comparison between this modified method and a high-performance liquid Chromatographic (HPLC) procedure was made using three commercial potato varieties and five experimental selections. Results from the two methods compared favorably.     

The influence of some soil physical properties on potato yields and grade distribution

Yields of U. S. No. 1 potatoes and numbers of deformed tubers were significantly correlated with air permeability near the surface and soil bulk densities down to 8 inches. Yields of No. 1 grade were correlated positively with soil air permeability and negatively with soil bulk density, whereas for deformed tuber production the correlations were the reverse. Total tuber production had a low correlation with soil factors because of the opposing responses of U. S. No. 1’s and deformed tubers. In a multiple-regression analysis, large variations in total yield, grade distribution, emergence rate, and final stand were accounted for by considering soil bulk density, soil strength, and air permeability. Production of quality tubers was closely associated with mechanical-impedance factors in the immediate zone of tuber development. Yields of U. S. No. 1’s were reduced 35% by a severe soil-compaction treatment in the beds.     

基于机器学习和无人机图像的棉花密度识别研究

随着人工智能的发展,机器学习正逐渐应用于大田信息化管理,可以节约时间、减少劳动用工。利用无人机获取6个密度（1.5万株·hm^－2、3.3万株·hm^－2、5.1万株·hm^－2、6.9万株·hm^－2、8.7万株·hm^－2、10.5万株·hm^－2）棉田的RGB图像,以数据增强技术扩大数据集,通过机器学习算法的不同模型（支持向量机、VGGNet16、GoogleNet、MobileNetV2）实现不同密度棉田图像的识别分类,并对比了不同模型的图像识别效果。基于支持向量机模型的方法是利用尺度不变特征变换对数据集进行特征提取,将其作为分类器的输入向量进行图像分类;该模型的平均分类识别准确率为74.18%。基于3种卷积神经网络模型（VGGNet16、GoogleNet、MobileNetV2）的方法是结合迁移学习并搭配Adam优化算法对模型进行微调,自动提取数据集特征并重新训练;其分类识别准确率均在90%以上。结果表明,相较于传统机器学习,3种卷积神经网络模型训练对不同密度棉田图像的分类识别准确率更高。比较4种神经网络模型的测试集验证结果,GoogleNet和MobileNetV2模型的平均分类识别准确率达到98%;结合模型评估指标精确率、召回率、F1分数可知,这2种模型的性能较好。该研究表明了深度学习算法对不同密度棉田图像分类的有效性,探索的图像识别方法和优选模型可为棉花大田信息化管理提供技术支持。     

Determination of drift potential of different flat fan nozzles on a boom sprayer using a test bench

This study's objective was to evaluate the functionality of an ad hoc test bench for spray drift measurement with boom sprayers, using it for evaluating different nozzles according to drift risk. The repeatability of results was evaluated by conducting similar tests at two different laboratories. Drift potential values (DPV) obtained showed an interesting effect of Venturi flat fan nozzles on drift reduction, in comparison with conventional flat fan nozzles (reference nozzle was XR 11003). Newly designed flat fan nozzles reduced the risk of drift. Reasonably relations between 10th-percentile, D[v,0.1], 50th-percentile or Volume Median Diameter, D[v,0.5], 90th-percentile, D[v,0.9], V₁₀₀ and DPV were observed in all cases, with R² values of 0.58, 0.65, 0.66 and 0.72, respectively. The lowest drift values were achieved with TTI and TD Spray Max nozzles; they were significantly lower than those obtained for IDK and AIXR ones. Results indicated that the drift test bench can be used as an alternative to the official standard procedure for drift measurements on boom sprayers (e.g. ISO 22866), as it is able to discriminate the influence of different boom settings (especially nozzle types) on drift. Further studies could be useful in order to prove that the classification of nozzles according to drift risk obtained using the test bench is comparable to the nozzle classifications obtained applying the ISO 22866 test method.     

Preparing the way for sterile insect release: Determination of false codling moth distribution across a landscape mosaic

Sterile insect release (SIR) for control of insect pests focuses on release of sterile individuals within the focal crop. Its success is related to the extent to which pest individuals are concentrated in the crop or spread out across the landscape mosaic. However, little is known of the success of SIR relative to spatial densities of target insect pest populations. This is especially so for the false codling moth (FCM) Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae), an indigenous moth to Africa and one of considerable phytosanitary significance. The aim here was to establish densities of the moth across a citrus production landscape in South Africa where the pest is particularly significant. Pheromone-baited delta traps were laid out in transects across a commercially important citrus-producing valley to assess the spatial and temporal distribution of wild males, prior to implementation of a commercial SIR programme. Transects included the focal citrus orchards, while also including a range of natural habitat types and elevation gradients. Male FCM were mostly confined to the citrus orchards, while those outside were close to citrus orchards or in alien alternative host plant patches, with only a few male individuals being caught up to 1.5 km from the nearest orchard. This suggests that the indigenous vegetation is supporting only a low FCM population, while, in contrast, citrus orchards are the main reservoir for FCM populations. These findings emphasize the importance of focussing SIR for FCM within the crop and on other, adjacent alien host plants, and not to dissipate releases into the surrounding and extensive natural vegetation.     

Estimation of water turbidity in Gorgan Bay, South-east of Caspian Sea by using IRS-LISS-III images

In this research, usefulness of IRS-LISS-III data of Gorgan Bay, South-east of Caspian Sea located in North of Iran for water turbidity mapping, has been tested. After correction of geometric and radiometric errors, the resulting radiance data were used for examination of correlations between the remotely sensed and in situ water turbidity data simultaneously measured by the Secchi depth approach. Results of this research showed good relations between the Secchi depth and spectral data. The fitted statistical model was very significant (R2 = 0.77) and test of the model performance by independent samples was encouraging. Because of the low costs encountered with acquisition and processing of remotely sensed data, further research in larger scales for the purpose of more precise test of the approach for water turbidity mapping and monitoring is recommended.     

Determination of relationships between the ultrasound velocity and the physical properties of bovine cortical bone femur

BACKGROUND: Accurate measurements of physical characteristics of bone are essential for diagnosis, assessment of change following treatment, and therefore, indirectly, for evaluation of new forms of therapy. This is particularly true of osteoporosis and aging skeleton, in which fractures occur easily. METHODS: In this study an ultrasonic system was set-up and calibrated on Plexiglas tubes of variable thickness then used to detect the cortical bone thickness change in calf and bovine adult femurs. Lamb waves have been generated and detected using a pair of Piezoelectric point transducers (transmitter and receiver) operating at 60 kHz in contact with the surface of the bone. RESULTS: A link has been established between the ultrasound velocity and the bone thickness. On the other hand, the density variation has been also investigated by the simulation of the bone decalcification chemically. The results show that the velocity is very sensitive to both thickness and density, its value reduces as the cortical bone thickness and density decrease. CONCLUSION: This technique might be considered in the attendance of certain bone diseases expressing itself by gradual change in physical properties.     

Evaluation of future climate change impact on snow hydrology for a mountainous watershed of South Korea using SLURP model and NOAA AVHRR images

This study is to evaluate the future potential climate impact on snow hydrology using SLURP model for a 6661.0 km² mountainous watershed of South Korea. For the model test, the NOAA AVHRR images were analyzed to prepare snow-related data of the model. Snow cover areas were extracted using channels 1, 3, and 4, and the snow depth was spatially interpolated using snowfall data of 11 ground meteorological stations. With the snowmelt parameters (snow cover area, snow water equivalent, and snow depth), the model was calibrated for 2 sets (2002–2003, 2004–2005), and verified for 2 sets (1997–1998 and 2001–2002) using the calibrated parameters. The average Nash–Sutcliffe efficiencies during the full year period (December to November) and snowmelt period (December to April) were 0.60 and 0.66, respectively. The future climate data of CCCma CGCM2 SRES A2 and B2 scenarios were adjusted and downscaled using change factor method. By the future impact of climate change, the annual dam inflows were projected to change maximum ?29.3 and ?30.4 % for 2090s A2 scenario and 2030s for B2 scenario, respectively. The future dam inflow increased in winter season (December to February) up to 222.0 %, while other periods decreased up to 54.8 %. The future snowmelt increased in December and January by the future temperature increase of 3.9 °C in minimum. The future snowmelt for the 2 months affected the dam inflows during the winter season.     

Characterizing the tensile properties of spun yarns using bivariate normal distribution

The tensile properties of spun yarns decisively influence its performance in various mechanical processing stages. This study is primarily aimed at simultaneous analysis of two tensile properties of spun yarns namely tenacity and breaking strain, which play crucial role in determining the frequency of warping breaks. The threshold values of yarn tenacity and breaking strain required for 20’s Ne carded cotton yarn to sustain the imposed stresses and strains during warping process have been determined using a bivariate normal distribution model. This study opens up the possibility of minimizing end breakage rate in various manufacturing processes of textile industry by engineering of spun yarns devoid of potential weak spots which are responsible for breaks.     

固相微萃取-气质联用法测定紫苏子挥发性成分

采用固相微萃取法(SPME)萃取紫苏子的挥发性物质,经气相色谱－质谱联用仪(GC-MS)检测,结果表明,紫苏子的挥发性成分主要由石竹烯、紫苏醛、a-石竹烯、柠檬烯、临氨基苯甲酸沉香酯、4-乙烯基－4-甲基－3-异丙烯基－1-异丙基－环己烯、(E,E)-1-甲基-5-亚甲基-8-异丙基-1,6-环癸二烯、2,6-二甲基-6-(4-甲基-3-戊基)双环[3.1.1]己-2-烯、1,4-二乙基-1,4-二甲基-2,5-环己二烯等组成,其中石竹烯相对含量最高（41.2 %）,紫苏醛次之(12.38 %)。     

Determination of thiabendazole residues in potatoes using high pressure liquid chromatography

Summary This paper describes a method for the extraction, purification and quantification by high pressure liquid chromatography using fluorimetric detection, of thiabendazole residues from potatoes. Bonded silica sorbent extraction columns (diol phase) are used for sample clean up, resulting in a rapid and accurate analysis. The average recovery was 93.8%±2.1%. Levels of about 0.0004μg of TBZ, equivalent to 0.033 mg kg⁻¹ in potatoes (on fresh weight basis), were readily detected from deliberately contaminted potatoes.