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“系统观”视域下的小学英语跨学科主题作业设计
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作者 林平珠 《教育实践与研究》 2024年第16期60-64,共5页
小学英语跨学科主题作业是跨学科学习中不可分割的一部分,以“系统观”为指引的跨学科主题作业设计应遵循以下七个要义:素养立意、主题视角、目标导向、任务驱动、情境创设、成果展示和总结评价,这七个方面形成一个结构化的、动态的循... 小学英语跨学科主题作业是跨学科学习中不可分割的一部分,以“系统观”为指引的跨学科主题作业设计应遵循以下七个要义:素养立意、主题视角、目标导向、任务驱动、情境创设、成果展示和总结评价,这七个方面形成一个结构化的、动态的循环系统,旨在提高英语跨学科作业设计评价的有效性,促进学生核心素养的发展,达到协同育人的效果。 展开更多
关键词 小学英语 跨学科主题 “系统观” 作业设计
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Research of CRP-based irregular 2D seismic acquisition 被引量:1
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作者 赵虎 尹成 +2 位作者 何光明 陈爱萍 敬龙江 《Applied Geophysics》 SCIE CSCD 2015年第1期73-78,122,共7页
Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-n... Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-noise ratio, and strong interference. The complexity of the subsurface structure leads to strong scattering of the refl ection points; thus, the curved-line acquisition method has been used. However, the actual subsurface structural characteristics have been rarely considered. We propose a design method for irregular acquisition based on common refl ection points(CRP) to avoid difficult-to-shoot areas, while considering the structural characteristics and CRP positions and optimizing the surfacereceiving line position. We arrange the positions of the receiving points to ensure as little dispersion of subsurface CRP as possible to improve the signal-to-noise ratio of the seismic data. We verify the applicability of the method using actual data from a site in Sichuan Basin. The proposed method apparently solves the problem of seismic data acquisition and facilitates seismic exploration in structurally complex areas. 展开更多
关键词 Geometry design irregular geometry acquisition design seismic data acquisition CRP analysis
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Powertrain Torque Control Based on Torque Observer 被引量:1
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作者 甘海云 赵长禄 +2 位作者 孙业保 葛蕴珊 张付军 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期220-224,共5页
To reduce shock during transmission gear shift, a transmission torque feedback closed loop control system is proposed based on the powertrain system model and a torque observer. The ignition time of engine was delaye... To reduce shock during transmission gear shift, a transmission torque feedback closed loop control system is proposed based on the powertrain system model and a torque observer. The ignition time of engine was delayed to reduce transmission output shaft torque during gear shift. In contrast to traditional control method, the closed loop control system based on torque observer can obviously reduce the transmission output shaft torque during gear shift. It can be concluded that by way of torque feedback closed loop control, transmission shift shock can be reduced. 展开更多
关键词 integrated powertrain control system torque observer automatic trasmission output shaft torque
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Ground Alignment of Inertial Navigation System with the Aid of GPS Signals 被引量:2
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作者 冯绍军 胡国辉 袁信 《Journal of Southeast University(English Edition)》 EI CAS 1998年第2期81-85,共5页
Due to the poor observability of INS ground self alignment, only horizontal alignment is satisfied. This paper proposes using GPS double difference carrier phase as external reference to improve the observability of ... Due to the poor observability of INS ground self alignment, only horizontal alignment is satisfied. This paper proposes using GPS double difference carrier phase as external reference to improve the observability of INS self alignment. Through observability analysis and computer simulation, it is demonstrated that the azimuth alignment is as quick as horizontal alignment, the accuracy of horizontal alignment is improved, and the gyros errors can be estimated quickly and precisely. 展开更多
关键词 inertial navigation system ALIGNMENT OBSERVABILITY GPS carrier phase
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Teaching English in the song of music:Toward a systemic framework for using English songs in EFL teaching 被引量:2
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作者 郭惠燕 《Sino-US English Teaching》 2007年第8期1-4,26,共5页
Guided by dialectical systemic thinking, this paper proposes a systemic framework for using English songs in EFL teaching. It first provides the philosophical, linguistic, psychological, pedagogical, and empirical bas... Guided by dialectical systemic thinking, this paper proposes a systemic framework for using English songs in EFL teaching. It first provides the philosophical, linguistic, psychological, pedagogical, and empirical bases for such an approach, then outlines the major processes in selecting and preparing English songs in lesson planning, and demonstrates the main procedures and aspects of using songs in classroom activities. It argues that the application of this approach will immediately stimulate the learners' interest in EFL learning and enhance the efficiency of EFL teaching. 展开更多
关键词 English songs EFL teaching dialectical systemic thinking
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Designing optimal number of receiving traces based on simulation model 被引量:1
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作者 赵虎 武泗海 +4 位作者 杨晶 任达 徐维秀 刘迪鸥 朱鹏宇 《Applied Geophysics》 SCIE CSCD 2017年第1期49-55,189,共8页
Currently, the selection of receiving traces in geometry design is mostly based on the horizontal layered medium hypothesis, which is unable to meet survey requirements in a complex area. This paper estimates the opti... Currently, the selection of receiving traces in geometry design is mostly based on the horizontal layered medium hypothesis, which is unable to meet survey requirements in a complex area. This paper estimates the optimal number of receiving traces in field geometry using a numerical simulation based on a field test conducted in previous research (Zhu et al., 2011). A mathematical model is established for total energy and average efficiency energy using fixed trace spacing and optimal receiving traces are estimated. Seismic data acquired in a complex work area are used to verify the correctness of the proposed method. Results of model data calculations and actual data processing show that results are in agreement. This indicates that the proposed method is reasonable, correct, sufficiently scientific, and can be regarded as a novel method for use in seismic geometry design in complex geological regions. 展开更多
关键词 Survey design GEOMETRY receiving trace number optimization forward modeling
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Research advance in forest restoration on the burned blanks 被引量:3
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作者 孔繁花 李秀珍 +1 位作者 赵善伦 尹海伟 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期180-184,共5页
How to restore the destroyed forest after forest fire is a key question that man must face. This paper reviewed the research situation and history on the forest restoration burned blanks and summed up the research met... How to restore the destroyed forest after forest fire is a key question that man must face. This paper reviewed the research situation and history on the forest restoration burned blanks and summed up the research methods used into four scales: seed-bank scale, community scale, ecosystem scale and landscape scale. The new technologies such as GIS & Remote Sensing used to vegetation restoration were also summarized. The strategies and developing trend of vegetation restoration research on burned blanks were discussed. 展开更多
关键词 Burned blanks Forest restoration Research advance Questions and countermeasures
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Digital Ocean Information Framework of China and its application in the international marine cooperation
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作者 于婷 邓增安 石绥祥 《Marine Science Bulletin》 CAS 2015年第1期86-96,共11页
Digital Ocean Information Framework (DOIF) has been proposed by China in 2011 based on the achievements of the comprehensive offshore oceanic surveys supported by Chinese Offshore Investigation and Assessment Progra... Digital Ocean Information Framework (DOIF) has been proposed by China in 2011 based on the achievements of the comprehensive offshore oceanic surveys supported by Chinese Offshore Investigation and Assessment Program, whose code name is 908. All observations from the surveys have been integrated and managed by DOIF. DOIF is capable of supporting the decision of making process for the sustainable use of marine resources in coastal regions of China, providing useful information and added value products as well as services for the improved management of the coastal areas in China with high business impact on the targeted groups as public authorities and commercial operators (e.g. managers, fishermen, shipping companies). The future vision of DOIF in the international marine data and information exchange and service at Western Pacific region is presented in this paper. 展开更多
关键词 digital ocean ocean observing system integrated data management decision making
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Global stabilization for a class of nonlinear time-delay systems using linear output feedback
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作者 柴琳 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期264-269,共6页
The stabilization problem via the linear output feedback controller is addressed for a class of nonlinear systems subject to time-delay.The uncertainty of the system satisfies the lower-triangular growth condition and... The stabilization problem via the linear output feedback controller is addressed for a class of nonlinear systems subject to time-delay.The uncertainty of the system satisfies the lower-triangular growth condition and it is affected by time-delay. A linear output feedback controller with a tunable scaling gain is constructed.By selecting an appropriate Lyapunov-Krasovskii functional the scaling gain can be adjusted to render the closed-loop system globally asymptotically stable.The results can also be extended to the non-triangular nonlinear time-delay systems. The proposed control law together with the observer is linear and memoryless in nature and therefore it is easy to implement in practice. Two computer simulations are conducted to illustrate the effectiveness of the proposed theoretical results. 展开更多
关键词 global stabilization nonlinear system time-delaysystem Lyapunov-Krasovskii functional linear observer memoryless controller
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ROBUST FAULT DIAGNOSIS FOR HELICOPTER FCS BASED ON LINEAR PARAMETERVARYING ADAPTIVE OBSERVER
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作者 陈伟 姜斌 +1 位作者 张柯 杨浩 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期288-294,共7页
Based on the linear parameter-varying (LPV) adaptive observer, the robust fault diagnosis for a class of LPV systems with external disturbances is studied. Since the flight control system (FCS) is nonlinear and ti... Based on the linear parameter-varying (LPV) adaptive observer, the robust fault diagnosis for a class of LPV systems with external disturbances is studied. Since the flight control system (FCS) is nonlinear and time-varying, the LPV technique is used for FCS. And then the adaptive fault estimation algorithm based on the LPV adaptive observer is proposed to estimate the fault. To minimize the effect of disturbances on the fault estimation, the H~ robust performance index is introduced to design the LPV adaptive fault diagnosis observer and the fault estimation algorithm. The result shows that the method has good estimation performance and is robust to external disturbances. The design method is presented in terms of linear matrix inequalities (LMIs). Finally, a helicopter LPV FCS model with the actuator fault is used to illustrate the effectiveness of the proposed method. 展开更多
关键词 fault diagnosis ROBUSTNESS flight control systems POLYTOPIC adaptive observer
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Design of No-Steady-Error and Anti-Disturbance Controller for Vehicular Servo Systems
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作者 孙常胜 梁钰 +2 位作者 陈杰 窦丽华 马岩峰 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期337-341,共5页
A modified method of design of no-steady-error and anti-disturbance controller is proposed for the design of tank stabilizers. Using a reduced-order observer to estimate its mode, disturbance can be compensated. This ... A modified method of design of no-steady-error and anti-disturbance controller is proposed for the design of tank stabilizers. Using a reduced-order observer to estimate its mode, disturbance can be compensated. This enables the system to resist sinusoidal disturbance with any magnitude. Estimate of angular velocity is used as the state feedback to replace the expensive gyro and tachometer generator. The modified method excels the traditional, and provides a new way for the design of tank fire control system. It can also be applied for the design of other servo systems in vehicle and aircraft. 展开更多
关键词 ANTI-DISTURBANCE fire control system servo system reduced-order observer ROBUST
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DESIGN OF NONLINEAR OBSERVER FOR NONLINEAR SYSTEM BASED ON RBF NEURAL NETWORKS
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作者 龚华军 Chowdhury F N 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期311-315,共5页
A new type of nonlinear observer for nonlinear systems is presented. Instead of approximating thc cntire nonlinear system with the neural network (NN), only the un-modeled part left over after the lincarization is a... A new type of nonlinear observer for nonlinear systems is presented. Instead of approximating thc cntire nonlinear system with the neural network (NN), only the un-modeled part left over after the lincarization is approximated. Compared with the conventional linear observer, the observer provides more accurate estimation of the state. The state estimation error is proved to asymptotically approach zero with the Lyapunov method. The simulation result shows that the proposed observer scheme is effective and has a potential application ability in the fault detection and identification (FDI), and the state estimation. 展开更多
关键词 observer nonlinear system state estimation neural network
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Epstein-Barr virus is associated with gastric carcinoma: The question is what is the significance? 被引量:4
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作者 Hugo Sousa Ana L Pinto-Correia +1 位作者 Rui Medeiros Mario Dinis-Ribeiro 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第27期4347-4351,共5页
AIM: To examine the possible role of the Epstein- Barr Virus (EBV) in the development of gastric adenocarcinoma (GC). It is unclear whether EBV is involved in GC development or is a consequence of gastric inflammation... AIM: To examine the possible role of the Epstein- Barr Virus (EBV) in the development of gastric adenocarcinoma (GC). It is unclear whether EBV is involved in GC development or is a consequence of gastric inflammation secondary to immunosuppressive treatments. METHODS: A systematic review was carried out of all published observational studies on the temporal association between EBV and GC, with a view to determine a causal relationship. RESULTS: The present study showed that the worldwide crude prevalence of EBV in gastric adenocarcinoma was 8.29%. The prevalence varied from 7.08% for intestinal type and 9.82% for diffuse type of GC. It was observed that Western and Central Asian countries had a significantly higher frequency of EBV positive cases compared to South-Eastern countries. America had the highest EBV-GC prevalence whereas Europe had the lowest. CONCLUSION: The present review has demonstrated a high prevalence of EBV in gastric adenocarcinoma. However, studies designed to assess a temporal relationship and histological association using sensitive techniques should be carried out to establish the role of EBV in GC carcinogenesis. 展开更多
关键词 Epstein-Barr virus infection Gastric carcinoma Systematic review
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Application of landscape ecology to the research on wetlands 被引量:5
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作者 WANG Ying-zi HONG Wei +3 位作者 WU Cheng-zhen HE Dong-jin LIN Shu-wei FAN Hai-lan 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期164-170,共7页
This review describes the characteristics and hot spots of wetland research, including biodiversity protection of wetland, management and restoration of wetland, function and process of wetland, and the theories, meth... This review describes the characteristics and hot spots of wetland research, including biodiversity protection of wetland, management and restoration of wetland, function and process of wetland, and the theories, methods and scales of landscape ecology. Moreover, some deficits of landscape ecology theory and method were discussed, and the application of landscape ecology to research on wetlands was reviewed specially, involving in the application of landscape structure principle, landscape pattern, and scale and hierarchy theory. In conclusion, landscape ecology plays an enlightening and guiding function on the comprehensive research of wetlands at multi-scales. 展开更多
关键词 WETLAND landscape ecology landscape structure landscape pattern scale and hierarchy
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Residential environment index system and evaluation model established by subjective and objective methods 被引量:30
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作者 葛坚 HOKAOKazunori 《Journal of Zhejiang University Science》 EI CSCD 2004年第9期1028-1034,共7页
In this research, the residential environment index system and evaluation model were established by means of subjective and objective methods. The methodology for establishing the evaluation system for residential env... In this research, the residential environment index system and evaluation model were established by means of subjective and objective methods. The methodology for establishing the evaluation system for residential environment was first analyzed; then the subjective evaluation data-base was established by questionnaire survey; and at the same time, the objective evaluation data-base was constructed by Geographic Information System (GIS); and then the related equation system between subjective and objective system was developed by multiple regression analysis. This research could benefit evaluation of the residential environment quality for various purposes, and also provide important rudimentary data-base for the development and improvement of residential environment for officials. Furthermore, the index system and evaluation model established in this research could construct a strong relation between subjective evaluation and objective data; and thus could provide a comprehensive, efficient and effective methodology for the evaluation of residential environment. 展开更多
关键词 Residential environment Index system Evaluation model Geographic information system (GIS)
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Local Responses to Macro Development Policies and Their Effects on Rural System in China's Mountainous Regions:The Case of Shuanghe Village in Sichuan Province 被引量:7
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作者 LI Yu-rui LIU Yan-sui +1 位作者 LONG Hua-lou WANG Jie-yong 《Journal of Mountain Science》 SCIE CSCD 2013年第4期588-608,共21页
China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differenc... China has promulgated a series of policies including the Western Development Program, the Grain for Green Project, agricultural support policies and building a new countryside strategy to eliminate east-west differences and urban-rural disparities since the late 1990s. This paper gives a holistic examination on local responses to the four typical macro socio-economic development policies and their effects on rural system based on a case study of a mountainous village in southern Sichuan Province. The results showed that the policies have not moved the case study village from its historically marginal status. To some extent, its socio-economic situation might have been worsened by accelerated out- migration of the youth, loss of agricultural land due to afforestation and industrial plants, increased fire hazard due to afforestation and reforestation, increased environmental pollution due to industrial enterprises attracted to the village and a steep decline in agricultural production due to loss of and inefficient use of cultivated land. Factors causing local villages' dilemmas include the nonuniformity of actors' objectives, finiteness of villagers' abilities, and the imperfect incentive and restraint mechanism for local government's activities under existing policy framework composed of uncoordinated one-size-fits- all policies. We suggest that China's rural policy in the new period should gradually shift from a sectoral to a place-based one, from top-down incentives to the development of bottom-up projects, and fully recognize the diversity of rural space, so as to lift localcapacities and make good use of the knowledge shared by different actors. Moreover, it is also necessary to integrate the various sectoral policies, and improve the interministerial and interdepartmental coordination of rural policies at regional and local levels. 展开更多
关键词 Local responses Western DevelopmentProgram Grain for Green Project Agriculturalsupport policies Building new countryside Ruralpolicy evaluation
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Improved strategy for estimating stem volume and forest biomass using moderate resolution remote sensing data and GIS 被引量:10
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作者 Arief Wijaya Sandi Kusnadi +1 位作者 Richard Gloaguen Hermann Heilmeier 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期1-12,I0001,共13页
This study presents the utility of remote sensing (RS), GIS and field observation data to estimate above ground biomass (AGB) and stem volume over tropical forest environment. Application of those data for the mod... This study presents the utility of remote sensing (RS), GIS and field observation data to estimate above ground biomass (AGB) and stem volume over tropical forest environment. Application of those data for the modeling of forest properties is site specific and highly uncertain, thus further study is encouraged. In this study we used 1460 sampling plots collected in 16 transects measuring tree diameter (DBH) and other forest properties which were useful for the biomass assessment. The study was carded out in tropical forest region in East Kalimantan, Indo- nesia. The AGB density was estimated applying an existing DBH - biomass equation. The estimate was superimposed over the modified GIS map of the study area, and the biomass density of each land cover was calculated. The RS approach was performed using a subset of sample data to develop the AGB and stem volume linear equation models. Pearson correlation statistics test was conducted using ETM bands reflectance, vegetation indices, image transform layers, Principal Component Analysis (PCA) bands, Tasseled Cap (TC), Grey Level Co-Occurrence Matrix (GLCM) texture features and DEM data as the predictors. Two linear models were generated from the significant RS data. To analyze total biomass and stem volume of each land cover, Landsat ETM images from 2000 and 2003 were preprocessed, classified using maximum likelihood method, and filtered with the majority analysis. We found 158±16 m^3.ha^-1 of stem volume and 168±15 t.ha^-1 of AGB estimated from RS approach, whereas the field measurement and GIS estimated 157±92 m^3.ha^-1 and 167±94 t.ha^-1 of stem volume and AGB, respectively. The dynamics of biomass abundance from 2000 to 2003 were assessed from multi temporal ETM data and we found a slightly declining trend of total biomass over these periods. Remote sensing approach estimated lower biomass abundance than did the GIS and field measurement data. The earlier approach predicted 10.5 Gt and 10.3 Gt of total biomasses in 2000 and 2003, while the later estimated 11.9 Gt and 11.6 Gt of total biomasses, respectively. We found that GLCM mean texture features showed markedly strong correlations with stem volume and biomass. 展开更多
关键词 above ground biomass stem volume remote sensing GIS field observation data
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Application of GPS technology to build a mine-subsidence observation station 被引量:16
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作者 LU Wei-cai CHENG Shi-guang +1 位作者 YANG Hai-sheng LIU Da-peng 《Journal of China University of Mining and Technology》 EI 2008年第3期377-380,共4页
We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers ... We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers various geologic and mining con-ditions. Having analyzed the aims of the joint survey and the comprehensive survey, we propose design principles, and work modes, for adopting GPS technology as the position measuring technique to be used in these two stages. Baseline vectors and spatial ad-justments of the GPS network were calculated after study of data processing and quality estimation methods. A coordinate system transformation and error estimates of the transformed GPS network data are discussed. The error estimates in all stages show that the GPS control network of the observation station has sufficient accuracy and is highly efficient. The network thus provides a reli-able datum for analyzing the laws of surface displacement and deformation induced by mining. 展开更多
关键词 GPS subsidence observation station initial observation data processing flow quality evaluating
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Research on basic characteristics of complex system brittleness 被引量:10
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作者 JINHong-zhang GUOJian WEIQi LINDe-ming LIQi 《Journal of Marine Science and Application》 2004年第1期57-63,共7页
The goal of this paper is to research one new characteristic of complex system. Brittleness, which is one new characteritic of complex system, is presented in this paper. The linguistic and qualitative descriptions of... The goal of this paper is to research one new characteristic of complex system. Brittleness, which is one new characteritic of complex system, is presented in this paper. The linguistic and qualitative descriptions of complex system are also given in this paper. Otherwise, the qualitative description of complex system is presented at first. On the basis of analyzing the existing brittleness problems, linguistic description and mathematic description of brittleness are given as well. Three kinds of phenomena to judge brittleness of complex system are also given, based on catastrophe theory. Basic characteristics of brittleness are given on the basis of its mathematic description. Two critical point sets are defined by using catastrophe theory. The definition of brittleness and its related theory can serve the control of complex system, and provide theoretical basis for the design and control of complex system. 展开更多
关键词 BRITTLENESS complex system CRITERION basic characteristic catastrophe theory
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A Real-Time System for Monitoring Distant Dynamic Displacement of Structures 被引量:4
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作者 CHEN Junfeng ZHAO Wenguang +2 位作者 LUO Hongbin LI Penghui WEN Yinping 《Geo-Spatial Information Science》 2008年第1期49-55,共7页
Based on digital image processing technique, a real-time system is developed to monitor and detect the dynamic displacement of engineering structures. By processing pictures with a self-programmed software, the real-t... Based on digital image processing technique, a real-time system is developed to monitor and detect the dynamic displacement of engineering structures. By processing pictures with a self-programmed software, the real-time coordinate of an object in a certain coordinate system can be obtained, and further dynamic displacement data and curve of the object can also be achieved. That is, automatic gathering and real-time processing of data can be carried out by this system simultaneously. For this system, first, an untouched monitoring technique is adopted, which can monitor or detect objects several to hundreds of meters apart; second, it has flexible installation condition and good monitoring precision of sub-millimeter degree; third, it is fit for dynamic, quasi-dynamic and static monitoring of large engineering structures. Through several tests and applications in large bridges, good reliability and dominance of the system is proved. 展开更多
关键词 dynamic displacement real-time monitoring and detecting SUB-PIXEL system calibration dynamic tracking
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