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Decentralized and overall condition monitoring system for large-scale mobile and complex equipment

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Journal of Systems Engineering and Electronics 2007年第4期18卷 758-763页

作者： cao jianjun Zhang Peilin Ren Guoquan Fu Jianping Dept. of Artillery Engineering Mechanical Engineering Coll. Shijiazhuang 050003 P. R. China Coll. of Mechanical Engineering Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China

It is an urgent project to realize online and overall condition monitoring and timely fault diagnosis for large-scale mobile and complex equipment. Moreover, most of the existing large-scale complex equipment has quite insufficient accessibility of examination, although it still has quite a long service life. The decentralized and overall condition monitoring, as a new concept, is proposed from the point of view of the whole system. A set of complex equipment is divided into several parts in terms of concrete equipment. Every part is processed via one detecting unit, and the main detecting unit is connected with other units. The management work and communications with the remote monitoring center have been taken on by it. Consequently, the difficulty of realizing a condition monitoring system and the complexity of processing information is reduced greatly. Furthermore, excellent maintainability of the condition monitoring system is obtained because of the modularization design. Through an application example, the design and realization of the decentralized and overall condition monitoring system is introduced specifically. Some advanced technologies, such as, micro control unit （MCU）, advanced RISC machines （ARM）, and control area network （CAN）, have been adopted in the system. The system＇s applicability for the existing large-scale mobile and complex equipment is tested.

关键词： condition monitoring fault diagnosis micro control unit information fusion

Leaf stoichiometry of Leontopodium lentopodioides at high altitudes on the northeastern Qinghai-Tibetan Plateau,China

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Journal of Arid Land 2022年第10期14卷 1124-1137页

作者： WANG Hairu SU Haohai Asim BISWAS cao jianjun College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China School of Environmental Sciences University of Guelph50 Stone Road EastGuelphOntario N1G 2W1Canada Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis College of Geography and Environmental ScienceNorthwest Normal UniversityLanzhou 730070China

Altitude affects leaf stoichiometry by regulating temperature and precipitation,and influencing soil properties in mountain *** carbon concentration(C),leaf nitrogen concentration(N),leaf phosphorous concentration(P),and their stoichiometric ratios of Leontopodium lentopodioides(Willd.)Beauv.,a widespread species in degraded grasslands,were investigated to explore its response and adaptation strategy to environmental changes along four altitude gradients(2500,3000,3500,and 3800 m a.s.l.)on the northeastern Qinghai-Tibetan Plateau(QTP),*** leaf C significantly varied but without any clear trend with increasing *** N showed an increasing trend,and leaf P showed a little change with increasing altitude,with a lower value of leaf P at 3500 m than those at other ***,leaf C:P and N:P exhibited a little change with increasing altitude,which both had greater values at 3500 m than those at other ***,leaf C:N exhibited a decreasing trend with increasing *** NH^(+)_(4)-N,soil pH,soil total phosphorus(STP),mean annual temperature(MAT),and mean annual precipitation(MAP)were identified as the main factors driving the variations in leaf stoichiometry of *** across all altitudes,with NH^(+)_(4)-N alone accounting for 50.8%of its total ***,leaf C and N were mainly controlled by MAT,soil pH,and NH^(+)_(4)-N,while leaf P by MAP and *** the study area,it seems that the growth of *** may be mainly limited by *** results could help to strengthen our understanding of the plasticity of plant growth to environmental changes and provide new information on global grassland management and restoration.

关键词： alpine area environmental changes leaf elements nutrient limitation Qilian Mountains

Floor stress evolution laws and its effect on stability of floor roadway

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International Journal of Mining Science and Technology 2013年第5期23卷 631-636页

作者： Zhang Hualei cao jianjun Tu Min School of Energy Resources and Safety Anhui University of Science and Technology State Key Laboratory Breeding Base for Mining Disaster Prevention and Control Shandong University of Science and Technology Gas Department Chongqing Branch China Coal Research Institute

According to the distribution of abutment stress in a stope,this research established the mechanical model of mining abutment pressure transmission in floor base on the theory of semi-infnite plate body in *** study takes the 762 working face of Haizi Coal Mine as a case in point,and analyzed the dynamic evolution law of seam floor stress during the mining *** an organic combination of the mining floor stress and surrounding rock stress,the study obtained the change laws of the maximum principle stress and the minimum one for the floor roadway surrounding rock when mining the upper working *** the non-constant pressure force state and the cracks revolution mechanisms of floor roadway surrounding rock,the research built the mechanical model of roadway *** results verify the reliability of the above ***,this model could provide the theoretical basis and technical support for controlling floor roadway surrounding rock.

关键词： Floor Mining abutment pressure Floor roadway Cracks evolution mechanisms

Regional features of topographic relief over the Loess Plateau,China:evidence from ensemble empirical mode decomposition

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Frontiers of Earth Science 2020年第4期14卷 695-710页

作者： Yongjuan Liu jianjun cao Liping Wang Xuan Fang Wolfgang Wagner School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou221116China School of Geography Science/Key Laboratory of Virtual Geographic Environment of Ministry of Education Nanjing Normal UniversityNanjing210023China School of Environmental Science Nanjing Xiaozhuang UniversityNanjing211171China Department of Geodesy and Geoinformation Vienna University of TechnologyVienna1040Austria

Landforms with similar surface matter compositions,endogenic and exogenic forces,and development histories tend to exhibit significant degrees of self-similarity in morphology and spatial *** loess hill-gully areas,ridges and hills have similar topographic relief characteristics and present nearly periodic variations of similar repeating structures at certain spatial scales,which is termed the topographic relief period(TRP).This is a relatively new concept,which is different from the degree of relief,and describes the fluctuations of the terrain from both horizontal and vertical(cross-section)perspectives,which can be used for in-depth analysis of 2-D topographic relief *** technique provides a new perspective for understanding the macro characteristics and differentiation patterns of loess *** investigate TRP variation features of different landforms on the Loess Plateau,China,by extracting catchment boundary profiles(CBPs)from 5 m resolution digital elevation model(DEM)*** profiles were subjected to temporal-frequency analysis using the ensemble empirical mode decomposition(EEMD)*** results showed that loess landforms are characterized by significant regional topographic relief;the CBP of 14 sample areas exhibited an overall pattern of decreasing TRPs and increasing topographic relief spatial frequencies from south to *** to the TRPs and topographic relief characteristics,the topographic relief of the Loess Plateau was divided into four types that have obvious regional *** findings of this study enrich the theories and methods for digital terrain data analysis of the Loess *** study should undertake a more in-depth investigation regarding the complexity of the region and to address the limitations of the EEMD method.

关键词： catchment boundary profile topographic relief period ensemble empirical mode decomposition Loess Plateau

An Object-based Approach for Two-level Gully Feature Mapping Using High-resolution DEM and Imagery： A Case Study on Hilly Loess Plateau Region, China

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Chinese Geographical Science 2017年第3期27卷 415-430页

作者： LIU Kai DING Hu TANG Guoan ZHU A-Xing YANG Xin JIANG Sheng cao jianjun Key Laboratory of Virtual Geographic Environment (Nanjing Normal University) Ministry of Education Nanjing 210023 China State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province) Nanjing 210023 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Department of Geography University of Wisconsin-Madison Madison 53711 USA School of Environmental Science Nanjing Xiaozhuang University Nanjing 211171 China

Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) and remote sensing imagery, combined with developed object-based methods enables automatic gully feature mapping. But still few studies have specifically focused on gully feature mapping on different scales. In this study, an object-based approach to two-level gully feature mapping, including gully-affected areas and bank gullies, was developed and tested on 1-m DEM and Worldview-3 imagery of a catchment in the Chinese Loess Plateau. The methodology includes a sequence of data preparation, image segmentation, metric calculation, and random forest based classification. The results of the two-level mapping were based on a random forest model after investigating the effects of feature selection and class-imbalance problem. Results show that the segmentation strategy adopted in this paper which considers the topographic information and optimal parameter combination can improve the segmentation results. The distribution of the gully-affected area is closely related to topographic information, however, the spectral features are more dominant for bank gully mapping. The highest overall accuracy of the gully-affected area mapping was 93.06% with four topographic features. The highest overall accuracy of bank gully mapping is 78.5% when all features are adopted. The proposed approach is a creditable option for hierarchical mapping of gully feature information, which is suitable for the application in hily Loess Plateau region.

关键词： object-based image analysis gully feature hierarchical mapping gully erosion Digital Elevation Model(DEM)

Sensitivity analysis for leaf area index （LAI） estimation from CHRIS/PROBA data

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Frontiers of Earth Science 2014年第3期8卷 405-413页

作者： jianjun cao Zhujun GU Jianhua XU Yushan DUAN Yongmei LIU Yongjuan LIU Dongliang LI The Key Laboratory of GIScience of the Education Ministry PRC East China Normal University Shanghai 200062 China School of Bio-chemical and Environmental Engineering Nanjing Xiaozhuang University Nanjing 211171 China

Sensitivity analyses were conducted for the retrieval of vegetation leaf area index （LAI） from multi- angular imageries in this study. Five spectral vegetation indices （VIs） were derived from Compact High Resolution Imaging Spectrometer onboard the Project for On Board Autonomy （CHRIS/PROBA） images, and were related to LAI, acquired from in situ measurement in Jiangxi Province, China, for five vegetation communities. The sensitivity of LAI retrieval to the variation of VIs from different observation angles was evaluated using the ratio of the slope of the best-fit linear VI-LAI model to its root mean squared error. Results show that both the sensitivity and reliability of VI-LAI models are influenced by the heterogeneity of vegetation communities, and that perfor- mance of vegetation indices in LAI estimation varies along observation angles. The VI-LAI models are more reliable for tall trees than for low growing shrub-grasses and also for forests with broad leaf trees than for coniferous forest. The greater the tree height and leaf size, the higher the sensitivity. Forests with broad-leaf trees have higher sensitivities, especially at oblique angles, while relatively simple-structured coniferous forests, shrubs, and grasses show similar sensitivities at all angles. The multi-angular soil and/or atmospheric parameter adjustments will hope- fully improve the performance of VIs in LAI estimation, which will require further investigation.

关键词： CHRIS/PROBA LAI sensitivity vegetationindex vegetation type

Status and Trends of China’s Refining and Petrochemical Industry

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China Oil & Gas 2023年第2期30卷 49-56页

作者： cao jianjun Sinopec Economics&Development Research Institute Company Limited

China’s refining and petrochemical industry has developed rapidly,with the quality of industry development improving *** scale of oil refining,ethylene,and PX ranks first in the world,and the quality of refined oil is among the world’s leading ***,the industry’s profitability is not strong enough,and there are still technological shortcomings,as well as defects in industry structure and product *** the backdrop of the dual carbon goals,energy transition,electric revolution,and demand differentiation,China’s refining and petrochemical industry will continue to exert efforts in energy conservation and consumption reduction,integrated development with new energy,promotion of oil conversion and the conversion of oil to special products,integration and upgrading of capacity,development of green hydrogen refining and CCUS,diversification of raw materials,circular economy,and other aspects to enhance industrial competitiveness.

关键词： petrochemical promotion refining

Optically induced transparency in a micro-cavity

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Light(Science & Applications) 2016年第1期5卷 831-835页

作者： Yuanlin Zheng Jianfan Yang Zhenhua Shen jianjun cao Xianfeng Chen Xiaogan Liang Wenjie Wan The State Key Laboratory of Advanced Optical Communication Systems and Networks and Collaborative Innovation Center of IFSA Department of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory for Laser Plasmas the University of Michigan-Shanghai Jiao Tong University Joint InstituteShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA

Electromagnetically induced transparency has the unique ability to optically control transparency windows with low light in atomic ***,its practical applications in quantum physics and information science are limited due to rigid experimental *** we demonstrate a new mechanism of optically induced transparency in a micro-cavity by introducing a four-wave mixing gain to nonlinearly couple two separated resonances of the micro-cavity in an ambient environment.A signature Fano-like resonance was observed owing to the nonlinear interference of the two coupled ***,we show that the unidirectional gain of the four-wave mixing can lead to the remarkable effect of non-reciprocal transmission at the transparency *** induced transparency may offer a unique platform for a compact,integrated solution to all-optical and quantum information.

关键词： Fano resonance induced transparency micro-cavity non-reciprocity

Terrain relief periods of loess landforms based on terrain profiles of the Loess Plateau in northern Shaanxi Province,China

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Frontiers of Earth Science 2019年第2期13卷 410-421页

作者： jianjun cao Guoan TANG Xuan FANG Jilong LI Yongjuan LIU Yiting ZHANG Ying ZHU Fayuan LI Key Laboratory of Virtual Geographic Environment of Ministry of Education Nanjing Normal UniversityNanjing 210023China School of Environment Science Nanjing Xiaozhuang UniversityNanjing 211171China

The Loess Plateau is densely covered by numerous types of gullies which represent different soil erosion ***,research on topographic variation features of the loess gullies is of great significance to environmental protection and ecological *** a5 m digital elevation model and data from a national geographic database,this paper studies different topographical areas of the Loess Plateau,including Shenmu,Suide,Yanchuan,Ganquan,Yijun,and Chunhua,to derive representative gully terrain profile data of the sampled ***,the profile data are standardized in MATLAB and then decomposed using the ensemble empirical mode decomposition ***,a significance test is performed on the results;the test confidence is 95% to 99%.The most reliable decomposition component is then used to calculate the relief period and size of the *** results showed that relief periods of the Chunhua,Shenmu,Yijun,Yuanchuan,Ganquan,and Suide gullies are 1110.14 m,1096.85 m,1002.49 m,523.48 m,498.12 m,and 270.83 m,*** terms of gully size,the loess landforms are sorted as loess fragmented tableland,aeolian and dune,loess tableland,loess ridge,loess hill and loess ridge,and loess hill,in descending *** together,the gully terrain features of the sample areas and the results of the study are approximately consistent with the actual terrain ***,we conclude that ensemble empirical mode decomposition is a reliable method for the study of the relief and topography of loess gullies.

关键词： loess gully DEM terrain profile EEMD Loess Plateau