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With the rapid development of computer and network technology, micro-blog system provides to exchange information and proceed social life. It provides very favorable ways. Especially, how to quickly obtain information and release information, sharing of information in today's society become a research direction for a big data. In this paper, we based on Struts2, JSP, MySql, Ajax and JQuery related...
Near-ground imaging spectroscopy is emerging as a promising sensing technique that can provide us with very fine spatial resolution imaging data for observing individual canopy components. It is an efficient tool to understand the within-canopy variation in spectral properties of paddy rice and resolve uncertainty sources in the spectroscopic estimation of rice chemistry. Many studies have use the...
The leaf optical model PROSPECT is widely used to retrieve leaf biochemical parameters, such as leaf chlorophyll content (Chl), carotenoid content (Car), leaf mass per area (LMA) and equivalent water thickness (EWT). Most methods for retrieving leaf pigment content are based on reflectance spectra and they may suffer from ill-posed problems in the inversion process. This study proposes a new inversion...
Timely and accurate estimation of rice planting area would greatly optimize our prediction of rice production, which provides invaluable information for government in formulating policies with regard to national food security. Previous studies have shown great potential of optical remote sensing as an effective way to map rice planting area. Commonly used classification techniques, which mainly focus...
Chlorophyll fluorescence (CF) is a direct indicator of plant physiology and reflects the photochemical process and its efficiency. CF is difficult to quantify because it is included in the reflected light. In the present study, the interrelationships between chlorophyll fluorescence parameters and spectral reflectance measured in the first, second, third and fourth leaves from the top of plant from...
The accurate prediction of crop yield is of great importance to regional production and food security. Many empirical models for crop production prediction are based on vegetation indices (VI) such as normalized vegetation index (NDVI) or simple ratio (SR) in specific growing period, with little attention paid to the sensitivity of different growing stages to yield prediction. This study investigates...
It is critical to estimate the biomass for assessing crop growth and predicting yield in crop. The hyperspectral techniques provide a powerful technique for monitoring crop biomass. The previous studies about using hyperspectral data to study crop mainly focused on models based on the full spectra or the manually selected spectra. The stability and prediction ability of full spectra models may be...
UAV based hyperspectral imaging is a promising approach to monitor crop growth status rapidly and non-destructively. This paper described a novel instrument to get hyperspectral information from lightweight unmanned aerial vehicles for crop monitoring. The objectives of this study were to assess the data quality of one hyperspectral frame camera and evaluate the ability in rice nitrogen status monitoring...
Leaf area index (LAI), as an important characterization parameter, reflects the canopy structural characteristics of crops. It is commonly used to estimate foliage cover, as well as forecasting crop growth and yield [1,2,3]. Because LAI is functionally linked to the canopy spectral reflectance, its retrieval from remote sensing data has prompted many investigations and studies in recent years. The...
The PROSPECT radiative transfer model was widely used to estimate leaf biochemical parameters, such as chlorophyll, leaf mass per area (LMA) and equivalent water thickness (EWT). Many studies have reported that LMA is the most difficult to retrieve from PROSPECT primarily because the dry matter absorption features on the reflectance spectra of fresh leaves are largely masked by stronger water absorption...
Unmanned Aerial Vehicles (UAV)-based remote sensing offers great possibilities to acquire in a fast and convenient way field data for precision agriculture applications. The UAV-based multispectral images with five wavebands (490, 550, 671, 700, 800 nm) were obtained at five growth stages from consecutive two years' wheat field experiments with different combinations in variety, N application rate...
The effect of canopy structure on the remote sensing of foliar nitrogen content has been debated in recent years, due to the uncertain mechanism of estimating foliar nitrogen content through canopy reflectance in the near-infrared region. Although this effect was investigated using the radiative transfer modeling of canopy structural influence, the complicated modeling implementation is still of limited...
The red edge position (REP) of a reflectance spectrum has been used as means to estimate the foliar chlorophyll content at leaf and canopy level. Most methods for extracting the REPs are based on the first derivative spectra and many studies have shown discontinuities in the REP data due to the existence of a double-peak feature in the first derivative spectra. This study proposes a new technique...
Recent studies have debated over the effect of canopy structure on the remote sensing of foliar nitrogen content. Although previous work reported on the radiative transfer modeling of canopy structural influence, the modeling implementation is still of limited use in the hyperspectral community. This study proposes to use a multi-scale tool, continuous wavelet analysis, to decompose the spectral responses...
Maize is one of China's major grain crops, it occupies a pivotal position in northern China. So there is great need to be informed the abreast of maize acreage, growth and yield of maize production timely for the management, price of macro-control and foreign trade. Implement yield estimation by RS is more advanced than any other traditional statistical methods in agricultural development. To obtain...
Game engine is the framework of the games. To develop a game engine owns good performance will reduce repetitive work and technical difficulties effectively during game development process. Considering the advantages and prospect of Android platform, the author studied the development principle of the game engine and Android platform, and then proposed a game engine on Android platform.
Frequent itemsets mining is a crucial problem in the field of data mining. Although many related studies have been suggested, these algorithms may suffer from high computation cost and spatial complexity in dense database, especially when mining long frequent itemsets or support threshold is very lower. To address this problem, a new data structure called P Array is proposed. P Array makes use of...
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