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Tn5.mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

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Progress in Natural Science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State Key Laboratory for Agrobiotechnology, college of Biological Sciences, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5.insertion library of A. brasilense Yu62 was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A24, were isolated. The sequence analysis of loci tagged showed that the Tn5.1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5.transposon.

Research progress on electrical signals in higher plants

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Progress in Natural Science:Materials International 2009年第5期19卷 531-541页

作者： Xiaofei Yana, Zhongyi Wang a, Lan Huang a, Cheng Wang b, Ruifeng Hou b, Zhilong Xu b, Xiaojun Qiao b a college of information and electrical Engineering, china agricultural university, beijing 1.0083, {5. b National Engineering Research Center for information Technology in Agriculture, beijing 100097, {5. [a]college of information and electrical Engineering China Agricultural University Beijing 100083 China [b]National Engineering Research Center for Information Technology in Agriculture Beijing 100097 China

This review introduces the characteristics of electrical signals in higher plants and their corresponding physiological significance, and describes in detail the impact of environmental factors (e.g. light and temperature) on the electrical potential of the plants. Also, we evaluate the measurement techniques used for electrical signals in plants, including intracellular measurement, extracellular measurement, measurement of the ion channel based on the patch-clamp technique and on the non-invasive microelectrode vibrating probe technique. We also give a brief review of the applications of these methods for investigating electrical signals in plants. The ionic mechanism of electrical activity in plants is then discussed in terms of environmental response in higher plants, and this is used to provide a theoretical basis for quantitative description of the electrical signals in plants. A model for interpretation of the electrical signal mechanisms in higher plants is discussed, but further experiments are required for the verification of this model.

关键词： Ion channel Temperature-induced Light-induced Ion mechanism Measurement technology

An Ontology-Based information Retrieval Model for Vegetables E-Commerce

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Journal of Integrative Agriculture 2012年第5期11卷 800-807页

作者： TAO Teng-yang ZHAO Ming college of information and electrical Engineering China Agricultural UniversityBeijing 100083P.R.China

With the rapid increment of the information on the web, traditional information retrieval based on the keywords is far from user＇s satisfaction in recall and precision. In order to improve the recall ratio and the precision radio of IR engine in the vegetables e-commerce, an information retrieval model based on the vegetables e-commerce ontology is presented in this paper, vegetables e-commerce ontology was constructed by gathering and the analyzing vegetables e-commerce domain information on the web. The vegetables e-commerce ontology is composed of some kinds of vegetable classes and hierarchy relationship of vegetables classes. In the process of information retrieval, domain ontology helps to index information and information inference. An ontology-based information retrieval model is implemented, and which has more functions than the keyword-based web information retrieval engines. The experiment results show that the recall ratio and the precision ratio of ontology-based information retrieval model are higher than that of the information retrieval engine based on keyword at a certain extent.

关键词： domain-ontology vegetables e-commerce information retrieval

On adjacent-vertex-distinguishing total coloring of graphs

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Science china Mathematics 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang college of Mathematics and information Science, Northwest Normal university, Lanzhou 730070, china Department of Computer, Lanzhou Normal college, Lanzhou 730070, china Institute of Applied Mathematics, Lanzhou Jiaotong university, Lanzhou 730070, china college of information and electrical Engineering, Lanzhou Jiaotong university, Lanzhou 730070, china Institute of Applied Mathematics, Chinese Academy of Sciences, beijing 100080, china 1. college of Mathematics and information Science Northwest Normal University 730070 Lanzhou China 2. Department of Computer Lanzhou Normal College 730070 Lanzhou China 3. Institute of Applied Mathematics Lanzhou Jiaotong University 730070 Lanzhou China 4. college of information and electrical Engineering Lanzhou Jiaotong University 730070 Lanzhou China 5. Institute of Applied Mathematics Chinese Academy of Sciences 100080 Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, LI Xiaoying1,2,3, ZHANG Yong1,2,3, ZHAO Feng1,2,3, GU Xingfa1,3,4, ZHU Li1,2,3, WANG Pengxin5.& MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate university of Chinese Academy of Sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. college of information and electrical Engineering, china agricultural university, beijing 1.0083, china 6. china Center for Resource Satellite Data and Application, beijing 100830, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate university of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. college of information and electrical Engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

Research on mobile GIS based for information collection

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Research on mobile GIS based for information collection

第十三届全国青年通信学术会议

作者： Chen Feixiang~1 Qi Jiandong~1 Zhao Ming~2 ~1college of information,beijing Forestry university,beijing 1.0083,{5. ~2college of information and electrical Engineering,china agricultural university,beijing 1.0083,{5.

＜正＞With the rapid development of GIS,embedded technology and wireless communication technology,mobile GIS becomes an active research area in the field of *** computing system based on personal digital assistant （PDA） products has been reed widely,and information collection is one of the most promising application directions of mobile *** purpose of the paper is to propose a solution of mobile GIS for information collection by studying the difference between PDA and traditional desktop cornputer. The main contributions include a novel new system architecture and detailed function of each ***,the method of data organization,the visualization of digital maps,spatial data compression,spatial data index,and spatial data transmitting by wireless networks *** on our strategy,a practical system is developed to prove the validity of our *** re- suits demonstrate our strategy can meet the actual need of the visualization,querying,editing,analyzing and transmitting of spatial information satisfyingly.

关键词： Mobile GIS PDA Embedded Devices information Collection.

New Method of Cotton Flow Speed Detection Based on Area CCD

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New Method of Cotton Flow Speed Detection Based on Area CCD

亚洲精细农业与计算机农业应用联合大会

作者： Gaili Gao Daoliang Li Shouhai Shang college of Engineering china agricultural university beijing 1.0083 china college of {5. and electrical Engineering china agricultural university beijing 1.0083 chinacollege of Engineering china agricultural university beijing 1.0083 china

In this paper, it is first proposed that area CCD may be used to detect the movement speed of cotton or foreign fibers in a cotton flow pipeline. A new method is presented for using the RGB color coordinates to identify CCD images of the cotton flow and adopting the RGB coordinate distance to distinguish the exact location of the same cotton line from two adjacent images. Eight CCD images of the different foreign fiber in cotton, a CCD image of raw cotton and a CCD image with a black background are selected. A 6×6 pixel small image is chosen from each of that ones. The RGB color coordinates of the small images are calculated with the use of the function from the Matlab image processing tools. It may be found that the RGB coordinate data of the different types of foreign fibers, the cotton and black background have a marked difference. By tracking the RGB coordinate datum sequence of some line pixel points in the images, the exact location of movement cotton or foreign fibers in two adjacent images can be identified. And furthermore according to the CCD frame rate, the instantaneous speed of the cotton flow or foreign fibers can be got.

关键词： cotton foreign fiber speed detection.

DCDDS: A Dairy Cow Disease Diagnosis System for Dairy Farm in china

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DCDDS: A Dairy Cow Disease Diagnosis System for Dairy Farm i...

第四届智能化农业信息技术国际学术会议

作者： Libin Rong~(1,2) Daoliang Li~(1,2,*) 1 china agricultural university,college of information and electrical Engineering,beijing 1.0083,{5. 2 Key Laboratory of Modem Agriculture System Integration,china agricultural university,beijing 1.0083

＜正＞Fish disease diagnosis is a complicated process and requires high level of ***, there’s no accepted general knowledge in fish disease *** paper describes a web-based CBR （case-based reasoning）system for fish disease *** of relying on general domain knowledge,CBR utilizes the specific knowledge of previous cases and solves a new problem by hunting out a similar case,and reusing it in the new problem.A two-step case retrieve model is proposed in this *** new case is initially identified which case base it belongs to,then the similarity is calculated using nearest neighbor method between the new case and the previous cases in the case base, finally the most similar one is found out and the solution is *** process of developing the web-based CBR system for fish disease diagnosis, the system structure and its components,such as knowledge base,case base and their functions,are described in this *** experiences with developing CBR system are discussed and conclusions are provided at the end of the paper.

关键词： Case-based reasoning Fish disease diagnosis Nearest Neighbor

Using Causality Analysis in the Beef Quality information Tracing

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Using Causality Analysis in the Beef Quality Information Tra...

第三届国际计算机及计算技术农业应用学术会议

作者： Hui Li~1 Daoliang Li~2 Weizhe Feng~3 Weisong Mu~2 Xinxing Li~4 Zetian Fu~(2*) 1 china agricultural university P.O.Box 209 beijing P.R.china 1.0083 2 college of {5. and electrical Engineering china agricultural university P.O.Box 209 beijing P.R.china 1.0083 3 International college at beijing china agricultural university beijing P.R.china 1.0083 4 college of Engineering china agricultural university P.O.Box 209 beijing P.R.china 1.0083

＜正＞Causal relation analysis is a promising application in product quality tracking and *** the quality safety problems in china beef production, the causal relation analysis was introduced into the beef quality safety tracing system and a causal approach-based tracing method was proposed. Considering the implicity,complexity and dynamic characteristics in beef quality safety causal relations, based on its mechanisms,a beef quality safety event representation method was studied based on the extended spanning tree *** the detection algorithm was developed based on an improved minimum spanning tree *** consideration of the time relations,hierarchical relations and causal relation between the beef quality safety events,an approach was proposed for the output of hierarchy view and solution of the causal tracing problems. Finally,through the investigation in the beef production manufactures,the proposed method got sound validation.

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