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- 2015
- Xanthomonas oryzae
- multispectral and multimodal microscopy
- spectroscopic imaging
- plant cell diseases
- classification
- rice
- Applied Physics
- University of Sciences, Technique and Technology Bamako
- Institut National Polytechnique Felix Houphou?t-Boigny Yamoussoukro
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[IEEE 2018 IEEE Southwest Symposium on Image Analysis and Interpretation (SSIAI) - Las Vegas, NV (2018.4.8-2018.4.10)] 2018 IEEE Southwest Symposium on Image Analysis and Interpretation (SSIAI) - Estimating Plant Centers Using A Deep Binary Classifier
摘要： Phenotyping is the process of estimating the physical and chemical properties of a plant. Traditional phenotyping is labor intensive and time consuming. These measurements can be obtained faster by collecting aerial images with an Unmanned Aerial Vehicle (UAV) and analyzing them using modern image analysis technologies. We propose a method to estimate plant centers by classifying each pixel as a plant center or not a plant center. We then label the center of each cluster as the plant location. We studied the performance of our method on two datasets. We achieved 84% precision and 90% recall on one dataset consisting of early stage plants and 62% precision and 77% recall on another dataset consisting of later stage plants.
关键词： Color Image Processing,Plant Phenotyping,CNN,Machine Learning
更新于2025-09-23 15:21:21
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Power Quality Management of PV Power Plant with Transformer Integrated Filtering Method
摘要： This paper presents a new solution of power quality management for the photovoltaic (PV) power plant with the transformer integrated filtering method. The innovation of the PV power plant is that it contains two-stage filtering station, which consists of a box-type transformer with filter and a 110 kV grid-connected transformer based on inductive filtering method. The filtering reactor can be integrated into the box-type transformer as a decoupled winding, so that the modular design of the box-type transformer and the passive filter are realized. Inductive filtering method applied transformer not only improves the power quality at the point of common coupling, but dampens the harmonic resonance between the passive filter and grid. The hierarchical structure of the PV power plant is introduced firstly. Then, the equivalent circuit model and the mathematical model of the primary filtering stations are established, and secondary respectively. Moreover, the influence of the weak coupling of integrated reactor on the filtering performance is analyzed. The antijamming capabilities of the inductive filtering method and the traditional filtering method are compared under the condition of parameter disturbance. At last, the site tests of the PV power plant with transformer integrated filtering method are made, which show that the PV grid-connected system comprised of the two-stage filtering station has the characteristics of low harmonic emission, high power factor and stable operation.
关键词： inductive filtering,Photovoltaic plant,integrated reactor,power quality
更新于2025-09-23 15:21:21
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Green Synthesis Approach for Nano sized CoFe2O4 through Aloe Vera Mediated Sol-gel Auto Combustion Method for High Frequency Devices
摘要： Nanosized CoFe2O4 was synthesized by Aloe vera-mediated sol-gel auto-combustion method. The yielded nanoparticles were characterised by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) to investigate the phase formation and morphology of the obtained powders. FTIR, XRD and Raman spectra revealed the formation of single phase CoFe2O4. FESEM micrographs showed the formation of some bud like structure and the particle size obtained is around 50-65?nm. Investigation of magnetic properties viz. saturation magnetization (Ms), remenant magnetization (Mr) and coercivity (Hc) were studied from the M-H loop and were found to be 72.23 emu/gm, 31.29 emu/gm, 1519 Oe respectively. In addition, the massive dielectric constant, low dielectric loss, and AC conductivity of the CoFe2O4 nanoparticles were dependent on the frequency (100 Hz-1 MHz), method of preparation and grain size. Room temperature ferroelectric measurement reveals a partially unsaturated P-E loop due to the high coercive field and influence of leakage current.
关键词： Aloe vera plant extract,magnetism,nanostructured materials,Dielectric properties,sol-gel auto combustion
更新于2025-09-23 15:21:21
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Data-integrity Checks and Balances in Monitoring of a Solar PV System
摘要： This paper proposes to perform certain integrity checks and balances to omit the wrong data in the monitoring of a solar PV plant. Further, these checks and balances are segregated into three types: basic, specific, and pattern checks. The former is performed on the data collected from all the types of sensors. However, the second check is performed on the data collected from the specific instruments. These checks are specific to the site, instrument, parameter, etc. The third check verifies the shape of profiles between the data of different sections of the PV system. For the data-inclusion/deletion purpose, the parameters of PV plant are segregated into a triangle-hierarchy of highest-least priority. Some of the proposed checks are performed on the raw data collected from a grid-tied 271 kW PV plant and 6.4 kW test PV plant. The results have indeed identified some of the bad data and validated the proposed checks.
关键词： photovoltaic (PV),PV plant health monitoring,data quality,data integrity,PV plant data,maximum power point tracking (MPPT)
更新于2025-09-23 15:21:01
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Coumarin Caged Compounds of 1-Naphthaleneacetic Acid as Light-Responsive Controlled-Release Plant Root Stimulators
摘要： Six coumarin caged compounds of NAA comprising different substituents on the coumarin moiety were synthesized and evaluated for their photo-physical and chemical properties as light-responsive controlled-release plant root stimulators. The 1H-NMR and HPLC techniques were used to verify the release of NAA from the caged compounds. After irradiation at 365 nm, the caged compounds exhibited the fastest release rate at t1/2 of 6.7 days and the slowest release rate at t1/2 of 73.7 days. Caged compounds at high concentration (10-5 M and 10-6 M) significantly stimulate secondary root germination while free NAA at the same level is toxic and leads to inhibition of secondary root germination. Cytotoxicity of the caged compounds against Fibroblasts and Vero cells were evaluated and the results suggested that at 10-5 – 10-6 M, caged compounds exhibit no significant cytotoxic to the cells. Thus, the caged compounds of NAA in this study can be of great benefits as efficient agrochemicals.
关键词： Photoremovable protecting groups,Agrochemicals,Coumarin caged compounds,Photocontrolled-release plant growth regulators,Plant root simulators,1-Naphthaleneacetic acid
更新于2025-09-23 15:21:01
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Effects of different LED lights and substrate media on growth of lettuce in an aquaponic system
摘要： Light emitting diodes (LED) are a good source of light energy because its light intensity can be adjusted, it has a low operating temperature as well as a long life and it uses less energy than other light sources. Current agriculture production places increasing emphasis on producing clean food, conserving the environment and effectively utilizing energy. Lettuce (Lactuca sativa L. ‘Ziwei’) production in an aquaponic system, exploiting waste excreted by fish as the plant fertilizer, was investigated. LEDs of various colour combinations were used as light sources for growing lettuce; included 1) fluorescent (a non-LED control), 2) white LED, 3) white and red LED (1:1), 4) white and red LED (1:2), 5) white and red LED (2:1) and 6) white, red and blue LED (1:1:1). Plants were grown on two substrates (laterite rock and expanded clay balls) in flood and drain aquaponic systems. Lettuce grown under white and red LEDs light (1:1, 1:2 and 2:1) on the laterite rock had the greatest plant height, leaf length, leaf width, leaf number, SPAD value, fresh and dry weight of stem and roots without iron deficiency symptoms. The combination of white and red LEDs lights (1:1, 1:2 and 2:1) and laterite rock has potential to improve growth of vegetables grown on aquaponic systems in greenhouse and plant factories.
关键词： laterite rock,clay balls and plant factory
更新于2025-09-23 15:21:01
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Two dimensional temperature measurement characteristics in pulverized coal combustion field by computed tomography-tunable diode laser absorption spectroscopy
摘要： Two dimensional temperature and concentration distributions are important parameters for pulverized coal combustion used for power plant to understand the combustion field and develop the high efficient combustion technologies. However, it is difficult to measure two dimensional temperature and concentration in pulverized coal combustion field using conventional measurement technologies because pulverized coal combustion produces lots of dust and strong emission from its flame. This paper focused on the application of two dimensional temperature measurement method based on the combination of computed tomography and tunable diode laser absorption spectroscopy using absorption spectra of water vapor at 1388nm and 1343nm for each laser scanning using direct absorption spectroscopy, which show the better characteristics of spatial-temporal resolution, fast response, high sensitivity, self-calibration and optical accessibility. Accuracy of temperature measurement using tunable diode laser absorption spectroscopy was improved by applying the corrected spectroscopic database. Computed tomography reconstruction accuracy of 16 laser-paths configuration was evaluated using sum of squared difference (0.001) and zero-mean normalized cross-correlation (over 0.991), which presented the consistent temperature between assumed and reconstructed distributions. This developed computed tomography-tunable diode laser absorption spectroscopy was successfully applied to pulverized coal flame for two dimensional temperature measurement with 1 ms temporal resolution for time-series two dimensional temperature measurement in the range of 300K-2500K. The rationality was demonstrated by comparison of pulverized coal flame and Methane-Air flame temperature distributions due to the main heat release produced by methane fuel. Its applicability to pulverized coal combustion field will be benefit for optimal operation control and combustion efficiency improvement by combustion organization or new design of combustion system.
关键词： Power plant,Pulverized coal combustion,Computed tomography (CT),Tunable diode laser absorption spectroscopy (TDLAS),Two dimensional temperature measurement
更新于2025-09-23 15:21:01
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The influence of the solar radiation database and the photovoltaic simulator on the sizing and economics of photovoltaic-diesel generators
摘要： This study evaluated the outcome differences when adopting five different solar irradiation databases on the sizing of hybrid solar photovoltaic-diesel generators designed to supply electricity to isolated minigrids. To do this, the two most widely adopted photovoltaic (PV) simulation packages in the market, namely PVsyst? and HOMER Energy? were used. The different origins, data timespan, space and time resolution, of the five most relevant solar irradiation databases available for the region were compared. A case study was presented to illustrate the influences of the solar irradiation database and the solar simulation tool on the resulting PV generator. Furthermore, the hourly behavior of the energy supply to an existing load in a minigrid in the Brazilian Amazon was evaluated, together with the savings in diesel obtained with the resulting PV generator. Evaluating the five options of solar radiation databases, for the same PV plant configuration, variations of up to 19.7% were found in the expectation of PV generation. When the simulation software package was varied, the combined effect (radiation database X PV system sizing tool) showed differences of up to 20.6%. This demonstrates that despite having different algorithms, computational tools have a small influence (less than 1%) on results. These combined differences, taking into account the load curve behavior and the total diesel generation capacity installed at the site, resulted in over 100% differences in the optimum PV generator size in the case study. The total savings in diesel fuel, over a 15-years period, ranged from $ 6.5 million to over $ 16 million (> 2.5 times) for the smallest PV system. This demonstrates the importance of the correct choice of database. These evaluations can be extended to minigrids of any size elsewhere. The novelty and originality of this study is to demonstrate and quantify for the first time the influence of the solar radiation database and the PV simulator package on the sizing of PV-diesel generators. The consequences of this study are not only of scientific and academic importance, but of economic and commercial interest as well.
关键词： Photovoltaic simulation tool,Hybrid photovoltaic-diesel power plant,Solar database,Minigrids,Solar irradiation
更新于2025-09-23 15:21:01
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[IEEE 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Design of an Ultra-Wideband Tightly Coupled Dipole Array
摘要： The superconducting stellarator Wendelstein 7-X is currently being commissioned. First plasmas are expected for the second half of 2015. W7-X is designed to overcome the main drawbacks of the stellarator concept and simultaneously demonstrate its intrinsic advantages relative to the tokamak—i.e., steady-state operation without the requirement of current drive or stability control. An elaborate optimization procedure was used to avoid excessive neoclassical transport losses at high plasma temperature, while simultaneously achieving satisfactory equilibrium and stability properties at high β in combination with a viable divertor concept. In addition, fast-ion confinement must be consistent with the requirements of alpha-heating in a power plant. Plasma operation of Wendelstein 7-X follows a staged approach following the successive completion of the in-vessel components. The main objective of Wendelstein 7-X is the demonstration of steady-state plasma at fusion relevant plasma parameters. Wendelstein 7-X will address major questions for the extrapolation of the concept to a power plant. These include divertor operation at high densities, plasma fueling at high central temperatures, avoiding impurity accumulation, and an assessment of the effect of neoclassical optimization on turbulent transport and fast-ion confinement. A power plant concept based on an extrapolation from Wendelstein 7-X, the helical advanced stellarator, has been developed.
关键词： Fusion power plant,steady-state magnetic confinement,stellarator
更新于2025-09-23 15:21:01
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Plant Growth and Photosynthetic Characteristics of Soybean Seedlings Under Different LED Lighting Quality Conditions
摘要： Light-emitting diodes (LEDs) have recently been widely used as light sources for the cultivation of plants in controlled environments. However, before LEDs can be used as the sole light source, it is imperative that soybean (Glycine max) response to light quality be well characterized. The objective of the present work was to investigate how soybean seedlings respond to different blue (B) and red (R) photon flux ratios (PFR) using LEDs. Light treatments were comprised of 170 ± 5 μmol m?2 s?1 photosynthetic photon flux density with B:R ratios of 0B:100R%, 10B:90R%, 25B:75R%, 50B:50R%, 80B:20R%, 90B:10R%, and 100B:0R%. Our results suggest that with the increase in B PFR from 0 to 90%, both plant height and specific leaf area inclined to decline while stem diameter gradually increased. The plants exposed to 80B:20R% showed unexpectedly greater total root length, root surface area, root volume, number of root tip, plant dry mass, leaf dry mass, root dry mass, leaf mass fraction and root mass fraction than plants exposed to all other treatments. Plants grown with 0B:100R% had the highest content of chlorophyll b (Chl b) and content of total chlorophyll [Chl (a + b)] but possessed the lowest ratio of the content of chlorophyll a to the content of chlorophyll b (Chl a/b). Plants grown with R alone also showed the lowest chlorophyll fluorescent parameters. The light-saturated CO2 assimilation rate (Asat) and the light-saturated stomatal conductance (gssat) for 0B:100R% were, respectively, 64.85% and 203.23% lower than those for 80B:20R%. However, plants grown with sole R accumulated higher soluble sugar and starch content during the daytime. Collectively, our results suggest that compared to R- or B-LED alone, an appropriate combination of R and B promotes plant growth and photosynthetic performance for soybean.
关键词： Soybean,Plant growth,Light quality,Photosynthetic characteristics,LED
更新于2025-09-23 15:21:01