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Wu H.,Chinese National Engineering Research Center for Information Technology in Agriculture | Wu H.,Key Laboratory for Information Technology in Agriculture | Gao R.,Chinese National Engineering Research Center for Information Technology in Agriculture | Gao R.,Key Laboratory for Information Technology in Agriculture
ICIC Express Letters, Part B: Applications | Year: 2013

Intelligent system is a hardware and software entity, which is able to understand and learn complex information and can make decisions and analyze behaviors. It has the capability of identifying objects and events, storing rich knowledge, reasoning and prediction. Considering the demand of intelligent system processing complex task, the method of multi-agent task cooperation process is proposed in this paper. Based on the idea of distributed artificial intelligence, a cooperative decision organizational framework of agent is organized, which is as the centre of project and task. Subsequently, a task description method of multi-agent is proposed, and immune memory, clone selection and affinity calculation all have been applied to solving the coordination problem and achieve low complexity and multi-task agent coordination mechanism. © 2013 ICIC International. Source


Miao T.,Beijing Research Center for Information Technology in Agriculture | Miao T.,ShenYang Agricultural University | Miao T.,Chinese National Engineering Research Center for Information Technology in Agriculture | Miao T.,Key Laboratory for Information Technology in Agriculture | And 12 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2016

Simulation of three-dimensional (3D) crop scene infected by crop disease is a tough task, because the related appearance data information is difficult to obtain. To obtain specific disease appearance information, careful bacteria culture and continuous observation may be needed with long-time experimental work and precise environmental control. This paper presents a general method to simulate the appearance transition of crop leaves infected by common diseases based on existing image in the Internet. We assume that a disease image contains some key appearance information in the process of disease infection. Based on this assumption, a set of static properties are extracted from image including shape and color of disease spots on the crop surface, and meanwhile the relevant dynamic transition processes of these properties are also deduced. For analyzing color transition, K-MEANS is firstly used to classify the color vectors of pixels in disease image into 8 categories and the average color vector of each category is computed which is called disease color feature vector. Then, these 8 vectors are sorted based on their proportions of green channel. To get a continual color aging simulation result, 7 linear functions are generated by interpolation between adjacent vectors. Finally, 141 discrete color vectors are sampled from these functions and used to generate the disease color transition texture. In order to obtain dynamic morphogenesis process of disease spot, the threshold segmentation method is firstly applied to segment the disease spot pixels from the pixels of normal crop leaves. Then a gray value is computed for each disease spot pixel based on the mimimum Euclidean distance between pixel's color vector and each disease color feature vector. These gray values of each disease spot pixel are recorded into the texture called morphogenesis texture. The distribution of disease spot on the crop organ surface is complex and random. A interactive interface tool has been developed for designing the distribution. With the tool, users can put some morphogenesis textures onto any location of the crop 3D models and change the size and direction of morphogenesis textures according to users' experience. The operating result is also saved as the texture called distribution texture. The disease color transition texture and distribution texture contain the necessary dynamic appearance information of disease spot and are used in the visualization step. For simulating a dynamic and continual appearance transition process of crop disease, a group of degree parameters for arbitrary 3D position on the crop surface are applied to generate the disease appearance which is computed using the distribution texture and the interactive parameter called general disease degree parameter. With the general degree parameter, user can get a simulation result under any infected state. In order to better define the disease appearance, we decompose it into the symptom appearance for describing the ageing status of the crop organ and the mildew layer appearance caused by the accumulation of mycelium. We consider the crop organ as a homogeneous structure and use the isotropic ward BRDF (bidirectional reflectance distribution function) model to simulate the symptom appearance. The diffuse reflection of ward model at arbitrary position on crop is selected from the color transition texture based on the degree parameter of this 3D position. In order to simulate the volumetric nature of the mildew layers, the shell model is integrated into our approach and the attributes of shell model are all controlled by the degree parameter. We have realized the algorithm in this paper using OpenGL, and found that the method can realistically render the appearance of the crop infected by the disease using only one or a few images. Our strategy is to use existing disease image from Internet to generate plant disease 3D animation, and it can solve the problem of the lack of related apparent data information of plant diseases. This research can provide a powerful tool to produce animations for agricultural science training. © 2016, Chinese Society of Agricultural Engineering. All right reserved. Source


Miao T.,Beijing Research Center for Information Technology in Agriculture | Miao T.,Chinese National Engineering Research Center for Information Technology in Agriculture | Miao T.,Key Laboratory for Information Technology in Agriculture | Miao T.,Beijing Key Laboratory of Digital Plant | And 21 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2016

Three-dimensional (3D) Plant modeling and visualization is a key research issue in both digital plant and agricultural application. Leaf is one of the vital organs in a plant, so the 3D modeling and shading of plant leaves is an important and fundamental work for achieving the goals of digital plant. Appearance simulation of plant leaves is still a challenging issue because of its intricate underlying structure and complex and subtle interaction with light. Texture mapping using leaf photo is a common method for appearance simulation, however, it could bring noise caused by light environment and camera position in lighting simulation step. This paper presents a technique for simulating the appearance of plant leaves with multiple images. Our method can estimate the spatially-varying reflectance properties of plant leaf surface based on a few images, which capture leaves' appearance transition information with different light directions. An apparent image acquisition system using linear light source is built for capturing 400 images with a fixed camera viewpoint and a single direction of motion for the linear light source. This system is composed of a driving module, a linear source module, a background module and a camera. Using a linear light rather than a point light source as the illuminant, we can obtain a piece of area with more intensive illumination. With these image data, we develop a fitting method, which is able to estimate the diffuse color, specular color and specular roughness of each point on the leaf surface. In our method, the isotropic ward model is utilized as the appearance model for specifying that how the leaf surface reflects light. Our fitting technique first simulates the change of reflectance attributes of diffuse and specular reflectance lobes under moving linear light source. In this process, a rectangle is employed to simulate the linear light source and Monte Carlo integration method is used to calculate the radiation transmission process. When we have the simulating results, the appearance parameters of each pixel are determined by comparing its actual parameter values to the simulating results. By above fitting method, 3 kinds of spatially-varying appearance parameters are saved into 3 parameter images for rendering leaf appearance. For quickly shading, multipoint point light sources are used for simulating various illumination conditions instead of complex radiative transfer integral. Using appearance parameter images and shading method, static appearance or dynamic appearance transition of plant leaves can be generated realistically. From the results obtained by this method, we find that it can render more accurate and real appearance texture of leaves compared to traditional texture mapping methods. The advantages of our method are that the appearance parameter images for rendering have removed the light and viewport noise, and only contained the appearance material information. In order to prove this conclusion, we quantitatively analyze the reason for this advantage by some formula derivations in this paper. But for obtaining these advantages, our method needs more complex data acquisition process and parameter fitting algorithm, which will reduce the efficiency of simulation. For improving the efficiency of our method, 2 approaches are discussed in this paper, including reducing image resolution and fitting the specular parameters of the whole leaf by a few sample points. Our method can estimate some appearance parameters which are plant leaf own intrinsic properties. We believe this characteristic will make these appearance parameters used not only for visualization, but also as some important phenotypes instead of so-called color data. In the future work, we will extend the application of our method in agriculture, such as monitoring plant growth status with the appearance parameters, or analyzing the differences among plant varieties. © 2016, Chinese Society of Agricultural Engineering. All right reserved. Source


Miao T.,Beijing Research Center for Information Technology in Agriculture | Miao T.,Key Laboratory for Information Technology in Agriculture | Miao T.,Shenyang University | Zhao C.,Beijing Research Center for Information Technology in Agriculture | And 7 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

3D agricultural scene under the condition of plant disease and insect pests is very difficult to simulate because of the complex appearance characteristics and severe apparent changes of the disease spots. The realistic appearance of plant leaves infected by the disease can't be obtained by the current methods. This paper presents a method to simulate the appearance of plant leaves infected by the disease. We assume that the disease spots uniformly distribute on the blade surface, spread from the spots center to the surrounding, and the shapes of the same kind of spots are similar. Based on these assumptions, the celluar bias function is used for controlling the shape, distribution and diffusion movement of the disease spot, and also for generating a 2D celluar texture image whose pixels represent the disease degree of any point on the blade surface. A degree parameter (in the range of 0 to 1) is used to adjust the pixel value of celluar texture to control the disease status, and the degree parameter equals 0 means there is no disease, and vice versa. We observed that some diseases can produce mildew layers on the leaf blade surface and which has volumetric, granular and arch form surface nature. In order to simulate the volumetric nature, the shell model is integrated into the approach. We use 15 passes to construct the shell model and use the degree parameter to discard the pixels which are not the mildew layers. For realistically rendering the grainy nature, the Perlin noise is applied to disturb the degree parameter for removing some pixels which belong to the mildew layers. With the purpose of generating an arch form mildew layer surface, we use the degree parameter to discard the pixels which belong to the larger passes of the shell model. Through this operation, the shell will present the height characteristics due to the gradual accumulation of the disease hyphae, middle part of the mildew layer is higher and the marginal part is lower. The optical property of the mildew layer is very hard to modeling because of the heterogeneous internal structure and the subsurface scattering property. In the approach, we construct a parameterized BRDF model to approximate the actual appearance. Owing to covering of the mildew, plant leaves ageing phenomenon happens. For rendering it, a leaf optical model with physiological factors is adopted, which can simulate the aging process by controlling some physiological parameters such as chlorophyll content and carotene content. The new method can be easily integrated with disease early warning model to simulate the disease appearance with different disease index or different environment parameters such as temperature and humidity. We realized the algorithm in this paper using OpenGL, and by comparing the rendering results to some actual disease images, we found that the method can realistically rendering the appearance of the plant leaves infected by the disease and insect pest. The research can provide a powerful tool to produce animations for agricultural science training. In the future work, we will focus on observing and analyzing some actual disease spread process to construct a more accurate parameter model for calculating the shape and the distribution of the disease spots. Source


Qian J.-P.,Chinese National Engineering Research Center for Information Technology in Agriculture | Qian J.-P.,Key Laboratory for Information Technology in Agriculture | Yang X.-T.,Chinese National Engineering Research Center for Information Technology in Agriculture | Yang X.-T.,Key Laboratory for Information Technology in Agriculture | And 8 more authors.
Journal of Food, Agriculture and Environment | Year: 2013

Traceability system is an effective measure to guarantee food quality and safety. Recently, IT-based vegetable traceability system with different information technology is focused on academic research and applied as pilot projects in some cities in China. This paper analyzes a structure of ITbased traceability system, including production identification, supply chain management system and central database. Based on the structure, traceability systems on different operating mechanisms are applied in two cities in China. A sample investigation with five parts is designed to analyze process and barriers of the operating mechanisms. Fifteen agribusinesses with the authorities-driven mechanism in Tianjin and 15 agribusinesses with the enterprise-driven mechanism in Guangzhou are selected for the investigation. The results show that the traceability systems with different driven mechanism have their own strengths and limitations. A framework for a vegetable traceability system integrated the strengths of two different operating mechanisms is proposed. Authorities department is responsible for the establishment of traceability service platform and setting uniform rules. Agribusiness enterprises are responsible for the development of information record system which is suitable for custom requirement on the uniform rules. Some measures are given to guarantee the system working well. Source

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