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“系统质”与“交流效应”
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作者 栗玉侠 《重庆通信学院学报》 1991年第1期F003-F003,共1页
现代管理的系统性原理告诉我们:当诸要素构成系统时,系统的整体性质和功能就在其组成它的要素性质和功能的基础上发生了质变,产生了系统质。也就是说。系统的整体属性和功能不是各组成要素属性和功能的简单相加。哲学命题为:整体不... 现代管理的系统性原理告诉我们:当诸要素构成系统时,系统的整体性质和功能就在其组成它的要素性质和功能的基础上发生了质变,产生了系统质。也就是说。系统的整体属性和功能不是各组成要素属性和功能的简单相加。哲学命题为:整体不等于各部分之和。系统理论的这一思想,对于人们的日常工作和生活均有一定的理论指导意义。 展开更多
关键词 通信院校 教育训练 “系统质” “交流效应” 管理学
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An Analysis of the Structure of Carbide-tool Utilization Expert System 被引量:1
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作者 庞思勤 张启元 于启勋 《Journal of Beijing Institute of Technology》 EI CAS 1996年第1期74-79,共6页
The necessity and feasibility of an expert system for carbide-tool utilization are analyzed and a practical system named CUES(carbide-tool utilization expert system ) is developed and realized. The system concept, mod... The necessity and feasibility of an expert system for carbide-tool utilization are analyzed and a practical system named CUES(carbide-tool utilization expert system ) is developed and realized. The system concept, module structure, data management, inference strategy and the interface design of the system are discussed in.detail. The system would be useful not only for the preparation of tool bank of FMS or CIMS, but the for the proper application of cemented carbide tools in conventional machining Processes. 展开更多
关键词 expert systems cemented carbides computer aided manufacturing tool management
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Bayesian and Multiple Bayesian Analysis of the Reliability Performances for Series System with Cold Standby Units 被引量:2
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作者 许勇 康会光 师义民 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期26-30,共5页
By using Bayesian and multiple Bayesian method, the failure probability, reliability and mean time to failure(MTTF) of series system with cold standby units are estimated. At last, we compare the two estimators by mea... By using Bayesian and multiple Bayesian method, the failure probability, reliability and mean time to failure(MTTF) of series system with cold standby units are estimated. At last, we compare the two estimators by means of Monte_Carlo simulation. 展开更多
关键词 ESTIMATION multiple Bayes reliability performance series system cold standby
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QUALITY ASSURANCE INFORMATION SYSTEM FOR AGILE MANUFACTURING
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作者 孙蓓蓓 钟秉林 +2 位作者 崔敏 黄仁 A kif A.Bulgak 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期71-77,共7页
The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With re... The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With recent dramatic advances in information technology, firstly the requirements of QAIS are examined in agile manufacturing environment, then a new implementation framework of a distributed QAIS is presented, where a deve loping environment of QAIS is established and some critical techniques are studied. Finally a prototype system based on world wide web (WWW) is accomplished. 展开更多
关键词 QUALITY quality control information system quality assurance agile manufacturing INTERNET INTRANET
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A Solenoid-Type Inductor Fabricated by MEMS Technique
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作者 高孝裕 周勇 +3 位作者 王西宁 雷冲 陈吉安 赵小林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1083-1086,共4页
A solenoid-type inductor for high frequency application is realized using a micro-electro-mechanical systems (MEMS) technique.In order to achieve a high inductance value and Q-factor,UV-LIGA,dry etching technique,fine... A solenoid-type inductor for high frequency application is realized using a micro-electro-mechanical systems (MEMS) technique.In order to achieve a high inductance value and Q-factor,UV-LIGA,dry etching technique,fine polishing and electroplating technique are adopted.The dimensions of the inductor are 1500μm×900μm×70μm,having 41 turns with a coil width of 20μm separated by 20μm spaces and a high aspect ratio of 3.5∶1.The maximum measured inductance of the inductor is 6.17nH with a Q-factor of about 6. 展开更多
关键词 inductance value microelectromechanical systems quality factor
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On the Motion of Controllable Mechanical Systems Having Variable Mass 被引量:1
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作者 朱海平 吴惠彬 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1994年第2期122-130,共9页
The differential equations of motion of a comtlaint system with parameters and variable mass, of a system with variable mass and servo constraints and those for the control problem on the forced motion of constraint s... The differential equations of motion of a comtlaint system with parameters and variable mass, of a system with variable mass and servo constraints and those for the control problem on the forced motion of constraint systems with variable mass are given respectively. Finally, an example is presented. 展开更多
关键词 variable mass systems/controllable mechanical system servo constraint forced motion
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Circulation Technology and Model of Agroforestry and Animal Husbandry
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作者 何成芳 闫晓明 +2 位作者 朱鸿杰 陈志豪 谭外球 《Agricultural Science & Technology》 CAS 2016年第6期1498-1505,共8页
On basis of analysis on agroforestry-animal husbandry ecosystem characters, the research explored nutrient flow model of material cycle and carbon cycle and agroforestry-animal husbandry mutualism model and supporting... On basis of analysis on agroforestry-animal husbandry ecosystem characters, the research explored nutrient flow model of material cycle and carbon cycle and agroforestry-animal husbandry mutualism model and supporting technology in Yangtze-Huaihe Region, taking Robinia pseudoacacia stand and rubber garden as an example. 展开更多
关键词 Eco-system between agriculture and animal husbandry Circulation of material Carbon cycle Technology system
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Analysis of a Class of Logical Functions over Galois and Z_m Rings 被引量:1
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作者 陈卫红 曾洪杰 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期105-110,共6页
In this paper, the author analyzed some cryptographic properties of a class of logical functions, f(x,y)=(q(x),...,q(x))·y+h(x),over Galois rings and residue rings, presented the relationship between the characte... In this paper, the author analyzed some cryptographic properties of a class of logical functions, f(x,y)=(q(x),...,q(x))·y+h(x),over Galois rings and residue rings, presented the relationship between the character spectrum of f(x,y) and the character speetrum of q(x),h(x) and the relationship between the cryptographic properties of f(x,y) and the cryptographic properties of h(x). 展开更多
关键词 logical function character spectrum cryptographic properties
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Admission Control Based on QoS for Third Generation Broadband Mobile Communication Systems
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作者 侯春萍 常倩 +1 位作者 曹达仲 范仲方 《Transactions of Tianjin University》 EI CAS 2002年第2期110-113,共4页
In this paper, a novel admission scheme is proposed which provides high degrees of quality of service (QoS) guarantees for multimedia traffic carried in mobile networks. The proposed scheme combines the admission cont... In this paper, a novel admission scheme is proposed which provides high degrees of quality of service (QoS) guarantees for multimedia traffic carried in mobile networks. The proposed scheme combines the admission control and bandwidth reservation to guarantee QoS requirements. It considers both local information and remote information to determine whether to accept or reject a connection. In order to embody the characteristics of the algorithms proposed in the article, two traditional algorithms of admission control are used for comparison. In the end of the paper the simulation analyses are given and the results show that the proposed algorithm can adjust the bandwidth according to the current status of networks and decrease the probability of connections forcibly dropped. The most important thing is that the algorithm is based on the multimedia communications and can guarantee the QoS of real time connections through decreasing the bandwidth of non real time connections. 展开更多
关键词 broadband mobile networks admission control quality of service guarantee
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Heterojunction between anodic TiO_2/g-C_3N_4 and cathodic WO_3/W nano-catalysts for coupled pollutant removal in a self-biased system 被引量:3
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作者 于婷婷 柳丽芬 杨凤林 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期270-277,共8页
An anodic TiO2/g-C3N4 hetero-junction and cathodic WO3/W were used to build a self-sustained catalytic fuel cell system for oxidizing rhodamine B or triclosan and reducing NO3^--N to N2 simultaneously.The WO3 nano-cat... An anodic TiO2/g-C3N4 hetero-junction and cathodic WO3/W were used to build a self-sustained catalytic fuel cell system for oxidizing rhodamine B or triclosan and reducing NO3^--N to N2 simultaneously.The WO3 nano-catalyst was formed in situ by heating and oxidizing a tungsten wire in air.Cyclic voltammetry and current-time curves were used to characterize the electrochemical properties of the electrodes and system.Aeration and activation of molecular oxygen by self-biased TiO2/g-C3N4 led to the formation of reactive oxidizing species in the fuel cell.The mechanism of simultaneous anodic oxidation of pollutants and cathodic reduction of nitrate was proposed.The spontaneously formed circuit and tiny current were used simultaneously in treating two kinds of wastewater in the reactor chambers,even without light illumination or an external applied voltage.This new catalytic pollution control route can lower energy consumption and degrade many other kinds of pollutants. 展开更多
关键词 Self-biased system Hetero-junction No light irradiation Low energy consumption Pollutant degradation
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NOTE ON FORMULATION OF GEOMETRIC PROPERTIES OF A POLYNOMIAL SYSTEM
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作者 郦志新 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期203-207,共5页
This note shows that when studying geometric pro perties, a polynomial system is defined as a line field on a projective space such that its singular set has co dimension at least 2. By this definition, the concept ... This note shows that when studying geometric pro perties, a polynomial system is defined as a line field on a projective space such that its singular set has co dimension at least 2. By this definition, the concept of the degree of a polynomial system does not coincide with the usual one. The usual degenerate polynomial system of degree n+1 should be regarded as a system of degree n . Note that the definition is independent coordinate system. And, by this definition, some geometric properties concerning polynomial vector fields turn out to be evident. 展开更多
关键词 polynomial vector fields line fields geome tric properties
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A New Approach to Prediction of Fault of Manufacturing Quality for FMS
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作者 张之敬 王信义 朱小燕 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期72-77,共6页
This paper makes a study of the cause of manufacturing fault,develops the and/or- fault-tree of manufacturing quality fault for MC,and presents a new concept of faint manufacturing quality fault(FMQF)and the decision ... This paper makes a study of the cause of manufacturing fault,develops the and/or- fault-tree of manufacturing quality fault for MC,and presents a new concept of faint manufacturing quality fault(FMQF)and the decision making tree with which the fault of manufacturing system would be found out from FMQF.An approach to identification of FMQF,based on fuzzy set theory,is presented,which can be used for estimating the status of equipment with the deviation of control charts.Based on the study above,an expert system for the flexible manufacturing system's FMQF detection and prediction is built. 展开更多
关键词 FMS faint manufacturing quality fault expert system fuzzy theory fault prediction
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Spectral Properties and Characterization of the Modified PSⅡ Core Complexes
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作者 李淑芹 陈耀东 +2 位作者 唐崇钦 李良璧 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第6期643-645,共3页
用组氨酸的特异性修饰剂 (DEPC)对PSⅡ核心复合物进行了化学修饰 ,并对其光谱性质进行了研究。研究结果表明 :修饰后的PSⅡ核心复合物的吸收光谱在红区发生了很大变化 ,随修饰时间的增加 ,6 80nm处的吸收逐渐下降。修饰后的PSⅡ核心复... 用组氨酸的特异性修饰剂 (DEPC)对PSⅡ核心复合物进行了化学修饰 ,并对其光谱性质进行了研究。研究结果表明 :修饰后的PSⅡ核心复合物的吸收光谱在红区发生了很大变化 ,随修饰时间的增加 ,6 80nm处的吸收逐渐下降。修饰后的PSⅡ核心复合物的荧光光谱在最初的 1min内出现荧光上升现象 ,然后逐渐下降 ,峰位蓝移。这些研究结果表明 ,组氨酸残基的修饰导致了原初电子供体P6 80结构的破坏 ,并对其功能产生了影响。 展开更多
关键词 PSⅡ core complexes spectral properties MODIFICATION
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Ice Surface-Elevation Change and Velocity of Qingbingtan Glacier No.72 in the Tomor Region,Tianshan Mountains,Central Asia 被引量:8
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作者 WANG Puyu LI Zhongqin +2 位作者 LI Huilin WANG Wenbin WANG Feiteng 《Journal of Mountain Science》 SCIE CSCD 2011年第6期855-864,共10页
Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2008 to 2009, a large-scale... Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2008 to 2009, a large-scale scientific expedition has been carried out in this region. As an individual reference glacier, the tongue area of Qingbingtan glacier No. 72 was measured by the high precise Real Time Kinematic-Global Position System (RTK-GPS). In this paper, changes of the tongue area of Qingbingtan glacier No.72 has been studied based on topographic map, remote sensing image and the survey during 2008-2009 field campaign. Results indicated that the ice surface-elevation of the tongue area changed - 0.22~0.14 m a-1 from 1964 to 2008. The estimated loss in ice volume was 0.0144-0.009 km3, which represented a ~20 % decrease from the 1964 volume and was equivalent to average annual mass balance of -0.204-0.12 m water equivalent for the tongue area during 1964-2oo8. Terminus retreated by 1852 m, approximately 41 m a-1, with the area reduction of 1.533 km2 (0.034 km2 a-0 from 1964 to 2009. Furthermore, the annual velocity reached to -70 m a-1. Comparing with the other monitored glaciers in the eastern Tianshan Mountains, Qingbingtan glacier No.72 experienced more intensive in shrinkage, which resulted from the combined effects of climate change and glacier dynamic, providing evidence of the response to climatic warming. 展开更多
关键词 Ice surface-elevation change Ice velocity Qingbingtan glacier No70 Tomor region TianshanMountains
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New Development of Reverse Micelles and Applications in Protein Separation and Refolding 被引量:9
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作者 刘杨 董晓燕 孙彦 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期949-955,共7页
Reverse micelles bring mild and effective microenvironments in organic solvent that contain bitmolecules, which have attracted immense attention for application in the isolation of proteins, protein refolding, and enz... Reverse micelles bring mild and effective microenvironments in organic solvent that contain bitmolecules, which have attracted immense attention for application in the isolation of proteins, protein refolding, and enzymatic reaction. In this review, the application of reverse micelles for protein separation and refolding has been briefly summarized and various reverse micellar systems composed of different surfactants, including ionic, non- ionic, mixed, and affinity-based reverse micelles, have been highlighted. It illustrates especially the potential application of the novel affinity-based reverse micelles consisting of biocompatible surfactant coupled with affinity ligands. Moreover, the importance to develop universal affinity-based reverse micelles for protein separation and refolding in the downstream processing of biotechnology has been pointed out. 展开更多
关键词 reverse micelles ionic surfactant nonionic surfactant AFFINITY protein separation protein refolding
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Coal and gas outburst dynamic system 被引量:23
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作者 Fan Chaojun Li Sheng +2 位作者 Luo Mingkun Du Wenzhang Yang Zhenhua 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第1期49-55,共7页
Coal and gas outburst is an extremely complex dynamic disaster in coal mine production process which will damage casualties and equipment facilities, and disorder the ventilation system by suddenly ejecting a great am... Coal and gas outburst is an extremely complex dynamic disaster in coal mine production process which will damage casualties and equipment facilities, and disorder the ventilation system by suddenly ejecting a great amount of coal and gas into roadway or working face. This paper analyzed the interaction among the three essential elements of coal and gas outburst dynamic system. A stress-seepage-damage coupling model was established which can be used to simulate the evolution of the dynamical system, and then the size scale of coal and gas outburst dynamical system was investigated. Results show that the dynam- ical system is consisted of three essential elements, coal-gas medium (material basis), geology dynamic environment (internal motivation) and mining disturbance (external motivation). On the case of CI 3 coal seam in Panyi Mine, the dynamical system exists in the range of 8-12 m in front of advancing face. The size scale will be larger where there are large geologic structures. This research plays an important guid- ing role for developing measures of coal and gas outburst prediction and prevention. 展开更多
关键词 Coal and gas outburst Dynamic system Coal-gas mediumlGeology dynamic environment Mining disturbanceStress-seepage-damage coupling model
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Dynamic Thermal Model and Temperature Control of Proton Exchange Membrane Fuel Cell Stack 被引量:5
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作者 邵庆龙 卫东 +1 位作者 曹广益 朱新坚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第2期218-224,共7页
A dynamic thermal transfer model of a proton exchange membrane fuel cell (PEMFC) stack is developed based on energy conservation in order to reach better temperature control of PEMFC stack. Considering its uncertain p... A dynamic thermal transfer model of a proton exchange membrane fuel cell (PEMFC) stack is developed based on energy conservation in order to reach better temperature control of PEMFC stack. Considering its uncertain parameters and disturbance, we propose a robust adaptive controller based on backstepping algorithm of Lyaponov function. Numerical simulations indicate the validity of the proposed controller. 展开更多
关键词 proton exchange membrane fuel cell stack dynamic thermal transfer model temperature control
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An experiment on digital library based on the method of TQM system 被引量:3
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作者 杨凌云 竺海康 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第11期1362-1366,共5页
The principles and methods of TQM (total quality management) were applied to digital library management. TQM puts emphasis on process control and continual improvement. The TQM theories and measures explained clearly ... The principles and methods of TQM (total quality management) were applied to digital library management. TQM puts emphasis on process control and continual improvement. The TQM theories and measures explained clearly in this paper were the scientific tools used in the experiment in the Wenzhou University Digital Library. This paper deals with a very broad range of subjects related to a digital library: system model of TQM for digital library, organization structure, and tasks of Wenzhou University Digital Library, task flow chart of electronic reading room, cause and effect of electronic reading room quality man- agement, systematic model of enhancing electronic information acquisition rate, quality comparison of electronic reading room service, etc. 展开更多
关键词 Total quality management (TQM) Digital library Process control
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GPS Real Time Supervisory System and Application in the Construction of Face Rockfill Dam 被引量:2
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作者 HUANG Shengxiang LIU Jingnan ZENG Huai’en 《Geo-Spatial Information Science》 2005年第4期240-246,共7页
According to the quality control needs of filling construction of the face rockfill dam, by means of the global satellite positioning technology, the wireless data communication technology, the computer technology and... According to the quality control needs of filling construction of the face rockfill dam, by means of the global satellite positioning technology, the wireless data communication technology, the computer technology and the data processing and analysis technology, and integrating with the roller compaction machine, the GPS real time supervisory system is developed in this paper. It can be used to real timely supervise the construction quality of the roller compaction for filling engineering. The composition and applied characteristics of GPS system, and the key technique problem and solution of the design are discussed. The height accuracy of GPS system is analyzed and the preliminary application is introduced. 展开更多
关键词 GPS filling construction quality control integrated system face rockfill dam
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Dynamics models of soil organic carbon 被引量:7
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作者 杨丽霞 潘剑君 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期323-330,共8页
As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and... As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China. 展开更多
关键词 Soil carbon Soil organic carbon Dynamic model
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