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亚洲精细农业与计算机农业应用联合大会

作者： Xingfu Xie 1 Gang Liu 1 Xiaozhe Lang 1 Qingkuan Meng 1 1 Key Laboratory of Modern Precision agriculture System Integration research china agricultural university Ministry of Education beijing 100083 china

Laser receiver was a key component of the laser-controlled land leveling system. In order to obtain better quality in laser signal detecting, operating range, stability and noise deduction, a novel design of a laser receiver based on integrated IC was developed. Red organic glasses were used as the in-light window, which could greatly reduce the background light into the laser receiver. Interference filters were also used at the laser receiver to further reduce the background light. Photo-electric cells were used to transform light signal into electrical signal. The low-noise pre-amplifier and main amplifier based on integrated amplifier was used to amplify the weak electrical signal effectively. The wave shaping circuit was employed to achieve better signal conditioning from spike pulse signal to digital TTL signal. The widening circuit was used to stretch the pulse width in order to be processed by the follow-up circuit more easily. Field experiments were carried out. The results show that the receiver work stable within 150m for all directions. The vertical operating ranger is 28.4cm which allows an accuracy of 2cm in land leveling.

关键词： Laser-controlled Land Leveling Laser Receiver Pre-amplifier Circuit Wave Shaping Circuit Widening Circuit

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A Fusion Method of the Time-Temperature Information for Aquatic Products in the Cold Chain

A Fusion Method of the Time-Temperature Information for Aqua...

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亚洲精细农业与计算机农业应用联合大会

作者： LIU Lu 1 ZHANG Jian 2 FU Zetian 1 1. College of Engineering china agricultural university beijing 100083 china 2. School of Economic Management beijing In formation Technology university Bei jing 100192 china

The most important aspect of fish spoilage is the effective monitoring and analyzing of the time-temperature condit ions during the cold chain, which affect both the safety and quality of fish. The time-temperature data is usually recorded by TTIs, TTE, and other indicators at very independent part of the cold chain, and stored in the database according to the cold chain management system. As the data files get increasingly large, the identification of the stage at the cold chain is immethodical to be classified automatically by time -temperature data. To realize the activity of the procedurals during the chain, the attributive time-temperature data files should be clearly presented and be sorted automatically in the database. In this paper, techniques of data fusion, data mining and their integration are used to recognize and classify the files corresponding with the processes during the cold chain intellect ively. Firstly, the constitution and common time-temperature data collection technique of the cold chain are analyzed. A framework of t ime -temperature data collection system is proposed by time-temperature indicators in conformity to the phases of the chain. The deposition of the indicator is also presented to get the time-temperature data at transportation. Secondly, data min ing is used to identify the character of time-temperature files. Rough Set theory, a tool of data min ing is imported to establishment of in formation expression system, to d ispersion and reduction of decision table. The creation of decision rules are elaborated by the algorithm. In this part, data mining is aiming for getting the rules induction fro m representative time-temperature file samples during the cold chain. Thirdly, data fusion theory is presented to automatically classify and storage on utilizing the rules founded. By using the classificat ion rules fro m data mining, data fusion ensures the now data collected by time-temperature indicators could be automatically sorted in

关键词： cold chain rough set data min ing data fusion time-temperature files

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Design ＆ Implementation of Data Communication Server in Farming Machinery Supervision System

Design ＆ Implementation of Data Communication Server in Far...

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亚洲精细农业与计算机农业应用联合大会

作者： LIU Yongsheng 1 2 CHENG Liping 2 CHEN Tianen 2 YAO Guangqiang 2 1College of Information Engineering Capital Normal university beijing 100037 china 2National Engineering research center for Information Technology in agriculture beijing 100097 china

In order to supervise the working process of the remote farming machinery on a large scale, it is necessary to deal with the real-time data such as oil consumption, speed and location coordinates of many farming machines effectively. Because of the following reasons, the data communication server which takes the charge of data processing and communicating has always been the performance bottleneck of the farming machinery supervision system. The first reason is that the amount of real-time data is large and the second reason is that the processing of real-time data must be in time. This paper uses the object-oriented programming method to design and implement a data communication server which is based on the sockets communication, thread pool and I/O multiplexing. In this paper, the multi-connection TCP communication and the high-speed concurrency processing of large amount of real-time data are subtly resolved. The circular queue data structure, the multiple thread technology and I/O multiplexing are used in the server to accept, process and store the farming machines’ real-time data. The constant thread pool and temporary thread pool are used to provide data for monitoring centre which are used to display the farming machines’ working status and the result of statistical analysis. The expansive communication protocols of application layer are designed in this paper to increase the ability of the communication among different models in the farming machinery supervision system. The class hierarchy is built up to increase the ability of code reuse. The data communication server as a primary part of the farming machinery supervision system has been tested in beijing Xing Lu He Farming Machine Server Company. The result indicates that the server’s stability and the efficiency of the real-time data processing can meet the requirement to supervise the working process of the remote farming machinery on a large scale.

关键词： Data communication server Thread pool I/O Multiplexing Sockets Communication protocols

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research on Wireless Sensor Node for Measurement of Vegetation Structure Parameters

Research on Wireless Sensor Node for Measurement of Vegetati...

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亚洲精细农业与计算机农业应用联合大会

作者： QU Yonghua 1 SUN Gang 2 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by beijing Normal university and the Institute of Remote Sensing Applications of chinese Academy of Sciences beijing china. 100875 2. College of Information and electric engine china agriculture university beijing china. 100083

Based on WSN（Wireless Sensor Network）technology, this article designed a wireless sensor network node for vegetation parameter’s measurement, which can be used at large space scale and in long temporal series measurement activity. Preliminary validation of the wireless sensor network node’s algorithm and performance are presented in this article. The results indicated that the algorithm can estimate the vegetation parameters accurately from the measurement of transmittance of radiance through the canopy. The relative error of estimated LAI（Leaf Area Index） is 5%, and the LIDF（Leaf Inclination Distribution Function）agree with that of real vegetation structure basically. The sensitivity of designed wireless sensor network node is tested by measuring transmitted light intensity of projected direct LED light to leaves which have been punched with different density hole. The results indicted that the measured transmittance of leaves has high correlation with the holes density though it was also found that value of the former was slightly lower than that of the latter.

关键词： Wireless sensor node vegetation Structure parameters

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Classification and identification of foreign fibers in cotton on the basis of a support vector machine

Classification and identification of foreign fibers in cotto...

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第三届国际计算机及计算技术农业应用学术会议

作者： Ronghua Ji~a,Daoliang Li~(a,*),Lairong Chen~b,Wenzhu Yang~a a College of Information and Electronic Engineering,china agricultural university,beijing,100083,china b School of Technology,beijing Forestry university,beijing,100083,china

Foreign fibers in cotton have seriously affected the quality of cotton *** classification and identification of foreign fibers in cotton is the foundation of cotton foreign fiber automated *** paper takes the typical cotton foreign fibers in china’s textile enterprises as the research object,and acquires the images under simulated actual cotton *** various classification features are calculated and *** results show that aspect ratio,roundness,duty cycle and I are the effective features for classifying various foreign *** paper puts forward a classifier of cotton foreign fibers based on a support vector machine.A Decision Tree Support Vector Machine(DTSVM) can not only avoid the non-separated region,but also improve the training speed while the training sample number gradually decreases,going through the decision *** DTSVM is to be used to identify the sorts of common foreign fibers in *** experimental data set shows that the rates of identifying different kinds of foreign fibers are greater than 92% using the proposed DTSVM.

关键词： Cotton Foreign fibers Classification features Support vector machine

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MEASUREMENT AND CONTROL SYSTEM FOR GREENHOUSE MICROCLIMATE BASED ON CANBUS

MEASUREMENT AND CONTROL SYSTEM FOR GREENHOUSE MICROCLIMATE B...

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The 3rd international Symposium on Intelligent Information Technology in agriculture(ISIITA)

作者： Linlin Qin~(1,2) Gang Wu~2 Meisheng Xue~2 Jun Wang~2 Demin Sun~2 Xiaojun Qiao~1 Weihong Luo~3 Dongliang Wang~4 ~1National Engineering research center for Information Technology in agriculture,beijing,100089,china ~2university of Science and Technology of china,Hefei,230027,china ~3 Nanjing agricultural university,Nanjing,210095,china ~4Anhui agricultural university,Department of Horticulture,Heifei,230036,china

＜正＞This paper describes the structure,constitutions, functions,and practical applications of a measured and control system for greenhouse microclimate,which is developed based on ***,a new advanced control algorith... 详细信息

关键词： Greenhouse climate CAN-bus Intelligent Bang-Bang Control

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A MODEL TO PREDICT SHELF-LIFE LOSS OF HORTICULTURAL PRODUCE DURING DISTRIBUTION WITH FLUCTUATED TEMPERATURE AND VEHICLE VIBRATION

A MODEL TO PREDICT SHELF-LIFE LOSS OF HORTICULTURAL PRODUCE ...

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The Second IFIP international Conference on Computer and Computing Technologies in agriculture (CCTA2008)

作者： Weiwei Gong1 Daoliang Li2 Xue Liu2 Jun Yue 2 3 Zetian Fu 1 * 1 College of Economics and Management china agriculture university beijing P. R. china 100083 2 College of Information and Electrical Engineering china agriculture university beijing P. R. china 100083 3 College of Management Ludong university Yantai Shandong Province P. R. china 264025

Fresh fruits and vegetables has become a public concern from the food security aspect. And the prediction of shelf-life loss under the fluctuated temperature becomes one of the key problems in food supply chain operation. So this paper identifies the impact aspects of produce decaying during distribution. For the key temperature factor, the process is divided into three phases: sorting, traveling and door-opening. Based on time-temperature function, a model of shelf-life loss of horticultural produce during distribution is developed by evaluating respiration rate of vegetables and fruits considering both the environment fluctuated temperature and vehicle vibration during traveling. Taking eggplant as an example, the numerical experiment result demonstrates that the average cost for ambient distribution is 2.8 times of the insulation way.

关键词： shelf-life horticultural produce distribution respiration rate

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博洛尼亚进程背景下的法国博士生教育改革

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外国教育研究 2009年第9期36卷 81-86页

作者：耿会芬教育部人文社会科学重点研究基地北京师范大学比较教育研究中心北京师范大学国际与比较教育研究所北京100875

在欧洲高等教育一体化的"博洛尼亚进程"中,法国以坚定的政治意愿投入改革,从而使法国的博士生教育呈现出崭新的面貌。改革使博士生的培养机制得以规范化,同时,加强与工商业的结合,职业化和国际化的培养理念为博士生教育注入了新的活力... 详细信息

在欧洲高等教育一体化的"博洛尼亚进程"中,法国以坚定的政治意愿投入改革,从而使法国的博士生教育呈现出崭新的面貌。改革使博士生的培养机制得以规范化,同时,加强与工商业的结合,职业化和国际化的培养理念为博士生教育注入了新的活力。但法国作为一个有着悠久的高等教育历史的国家,改革也遇到了来自制度和文化等方面的阻力。

关键词：法国博洛尼亚进程研究生教育博士生教育

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Using hyperspectral indices to estimate foliar chlorophyll a concentrations of winter wheat under yellow rust stress

Using hyperspectral indices to estimate foliar chlorophyll a...

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The First international Conference on Computers and Computing Technologies in agriculture

作者： LI JING~(1,2) JIANG JINBAO~1 CHEN YUNHAO~(1,2,*) WANG YUANYUAN~1 SU WEI~3 HUANG WENJIANG~4 1 College of Resources Science and Technology beijing Normal university No.19 Xinjiekouwai Street beijing 100875,china 2 State Key Laboratory of Earth Surface Processes and Resource Ecology beijing Normal university No.19 Xinjiekouwai Street beijing 100875,china 3 College of Information & Electrical Engineering china agricultural university beijing 100083,china 4 National Engineering research center for Information Technology in agriculture beijing 100089,china

The canopy hyperspectral reflectance of winter wheat infected with yellow rust at different levels of severity were measured by an ASD FieldSpec Pro FR spectrometer in the field and the concentrations of chlorophyll a(Chl a) in the leaves corresponding to the spectra were determined by biochemical methods in the *** analyses were made between Chl a concentrations and canopy hyperspectral data of diseased wheat. Results show that foliar Chl a concentrations are strongly correlated with canopy spectrum in the visible region and the first-order derivative spectrum in blue edge,green edge,and red *** and nonlinear models for estimating Chl a concentrations of the diseased wheat were built based on several spectral *** indicate that SDr/SDg,in which SDr and SDg are the sums of the first derivative within red and green edges,outperformed the other indices in predicting Chl a *** relative estimation errors for Chl a for 12 unseen samples are 17.5%.It is concluded that derivative spectra in red edge and green edge have strong prediction power for foliar Chl a concentrations of diseased winter *** hyperspectral remote sensing data to monitor crop disease and nutrition status is very promising.

关键词： chlorophyllα estimation models hyperspectral wheat yellow rust stress

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哈佛大学办学理念探析

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外国教育研究 2003年第1期30卷 48-53页

作者：刘宝存北京师范大学比较教育研究中心北京100875

哈佛大学在其360多年的历史中,一直固守着寻求真理的办学宗旨。坚持大学的多职能性,把教学(人才培养)看作大学最重要的职能之一。它以培养有教养的人、全面发展的人为人才培养目标,并通过通专结合的课程体系、以培养独立思考能力为取向... 详细信息

哈佛大学在其360多年的历史中,一直固守着寻求真理的办学宗旨。坚持大学的多职能性,把教学(人才培养)看作大学最重要的职能之一。它以培养有教养的人、全面发展的人为人才培养目标,并通过通专结合的课程体系、以培养独立思考能力为取向的教学方法、宽松自由的学术环境、独特的寄宿制和导师制、丰富多彩的课外活动等措施,促进人才培养目标的实现。

关键词：哈佛大学办学理念美国人才培养课程体系学术环境

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