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基于PC-E500的道路测设系统 被引量:4
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作者 闻道秋 郑加柱 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第3期109-112,共4页
详细地介绍了在PCE50 0计算机上建立的道路测设系统和它的功能 ,讨论了系统设计中需要解决的问题 ,给出了解决方法 .该系统解决了如何在野外现场利用袖珍计算机快速计算复杂线形的中桩坐标、边桩坐标 .系统能快速地测设路线加桩 ,确定... 详细地介绍了在PCE50 0计算机上建立的道路测设系统和它的功能 ,讨论了系统设计中需要解决的问题 ,给出了解决方法 .该系统解决了如何在野外现场利用袖珍计算机快速计算复杂线形的中桩坐标、边桩坐标 .系统能快速地测设路线加桩 ,确定任意点到路线的距离等 ,同时该系统亦适用于路线检测 .当采用全站仪测设路线时 ,利用本系统可大大地提高测设效率 .经实践证明该系统设计合理 ,使用简单方便 ,适用于任意线型的路线 ,包括匝道 。 展开更多
关键词 PC-E500 坐标 曲线要素 道路测设系统 公路建
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实用公路工程平面线形测设系统的开发
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作者 马健霄 庄岩 席红泽 《森林工程》 2000年第6期56-57,8,共3页
针对目前公路工程平面线形,特别是平面曲线,在计算、设计、敷设工作上烦琐,工作效率低,容易出现差错等现状,本文对所开发的软件系统从系统需求到系统实现作了说明。经实际应用、验证了该系统的实用、易操作和高可靠性。
关键词 平面线形 曲线敷 公路工程 测设系统 系统开发
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RSS高级公路测设系统
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作者 徐时涛 冯晓 《测绘技术》 1992年第4期8-14,共7页
关键词 公路 勘探 测设系统 RSS
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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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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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Sea water temperature auto-monitoring system based on general packet radio service (GPRS) 被引量:1
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作者 张文孝 高国栋 慕关羽 《Agricultural Science & Technology》 CAS 2006年第3期13-18,共6页
This paper introduces the design and implementation of sea-water temperature auto-monitoring system based on General Packet Radio Service (GPRS). This system integrates modern wireless communication technology, the ... This paper introduces the design and implementation of sea-water temperature auto-monitoring system based on General Packet Radio Service (GPRS). This system integrates modern wireless communication technology, the signal gathering technology and computer network technology. MSC1210 microcontroller is used in data collection device in order to make system accurate and fast. In addition, wireless and Internet technologies are used for transferring and displaying collected field data. A prototype system has been completed and tested in field trials. The results proved the feasibility and usefulness of this system for monitoring the temperature. By using this system, a lot of resources and money can be saved. 展开更多
关键词 SENSOR MSC1210 GPRS remote monitor
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The Research and Application of the Anti-Interference Techniques of Electronic Device in Power System 被引量:1
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作者 吴维宁 张文亮 +1 位作者 吴峡 李建建 《Electricity》 2001年第4期40-43,共4页
This paper presents the study and application of the electronic device anti-interference techniques underhigh voltage and/or heavy current electro-magnetic circumstance in power system.[
关键词 electric power system electronic measurement and/or control device anti-interference measures
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Study and Application of Objective Evaluation Model on Fabric Style 被引量:1
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作者 王国和 梁颜芳 顾平 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期187-191,196,共6页
Based on 31 fabric property parameters tested by FAST test system and other test instruments, the principal factors of fabric style are obtained through the principal factor analysis method and computer program. Accor... Based on 31 fabric property parameters tested by FAST test system and other test instruments, the principal factors of fabric style are obtained through the principal factor analysis method and computer program. According to the correlation between each parameter and principal factor, the selected positive or negative coefficient, the objective evaluation model of fabric style has been established based on the percentage of variance. And wool fabrics have been taken for example to show how to use the objective evaluation model for fabric design. 展开更多
关键词 principal factor analysis method fabric style FAST test system evaluation model fabric design
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Loading System for Full-Scale Heavy-Duty Support Node Test with Multi-Directional Loading Requirements 被引量:3
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作者 王玉银 龚超 +1 位作者 张素梅 郭海山 《Transactions of Tianjin University》 EI CAS 2011年第3期166-174,共9页
This paper presents the design, analysis and experimental study of a loading system for heavy-duty nodes test based on a large-scale multi-directional in-plane loading device, which has been used in a full-scale heavy... This paper presents the design, analysis and experimental study of a loading system for heavy-duty nodes test based on a large-scale multi-directional in-plane loading device, which has been used in a full-scale heavy-duty support node test. Test loads of the support reached 6 567 kN with multi-directional loading requirements, which outrange the capacity of the available loading devices. Through the reinforcement of a large-scale multi-directional inplane loading device, the innovative design of a self-balanced load transferring device, and other arrangement considerations of the loading system, the test was implemented and the loading capacity of the ring was considerably enlarged. Due to the heavy loading requirements, some checking computations of the ring and the load transferring device outranged the limit of the Chinese national code "Code for Design of Steel Structures (GB 50017—2003)", thus elastic-plastic finite element (FE) analysis was carried out on the two devices, and also the real-time monitoring on the whole loading systems during experiments to ensure test safety. FE analysis and test results show that the loading system worked elastically during experiments. 展开更多
关键词 loading system self-balanced design multi-directional loading heavy-duty node
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LISP-PCHORD:An Enhanced Pointer-Based DHT to Support LISP 被引量:2
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作者 张泰 王晟 廖丹 《China Communications》 SCIE CSCD 2013年第7期134-147,共14页
Aiming to efficiently support theLocator/Identifier Separation Protocol(LISP),in this paper,we present an enhanced pointerbased DHT mapping system:LISP-PCHORD.The system creates a pointer space to build ontop of stand... Aiming to efficiently support theLocator/Identifier Separation Protocol(LISP),in this paper,we present an enhanced pointerbased DHT mapping system:LISP-PCHORD.The system creates a pointer space to build ontop of standard DHTs.Mappings within thepointer space are(Endpoint Identifiers(EID),pointers) where the pointer is the address ofthe root node(the physical node that stores themappings) of the corresponding(EID,RoutingLocators(RLOCs)) mappings.In addition toenabling architectural qualities such as scalability and reliability,the proposed LISP-PCHORDcan copy with flat EIDs such as self-certifyingEIDs.The performance of the mapping systemplays a key role in LISP;however,DHT-basedapproaches for LISP seldom consider the mismatch problem that heavily damages the system performance in terms of lookup latency.In order to mitigate the mismatch problem andachieve optimal performance,we propose anoptimization design method that seeks an optimal matching relationship between P-nodes(nodes within the pointer space) and the physical nodes on the basis of the given lookuptraffic matrix.In order to find the optimal matching relationship,we provide two solutions:a linear programming method and a geneticalgorithm.Finally,we evaluate the performance of the proposed scheme and compare itwith that of LISP-DHT. 展开更多
关键词 communication network mapping system LISP DHT linear programming genetic algorithm
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Global Robust and Adaptive Output Feedback Dynamic Positioning of Surface Ships 被引量:10
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作者 Khac Duc Do 《Journal of Marine Science and Application》 2011年第3期325-332,共8页
A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean current... A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean currents. The ship's parameters were not required to be known. An adaptive observer was first designed to estimate the ship's velocities and parameters. The ship position measurements were also passed through the adaptive observer to reduce high frequency measurement noise from entering the control system. Using these estimate signals, the control was then designed based on Lyapunov's direct method to force the ship's position and orientation to globally asymptotically converge to desired values. Simulation results illustrate the effectiveness of the proposed control system. In conclusion, the paper presented a new method to design an effective control system for dynamic positioning of surface ships. 展开更多
关键词 dynamic positioning surface vessel robust and adaptive output feedback nonlinear control
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Introduction to the TT&C Scheme for Chang’e⁃5 Mission
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作者 HUANG Lei LI Haitao +2 位作者 DONG Guangliang CHEN Shaowu FAN Min 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第5期530-540,共11页
Chang’e-5 mission is China’s first lunar sample return mission.It contains several new flight phases compared with the previous lunar missions,such as the lunar take-off and orbit insertion phase,the rendezvous and ... Chang’e-5 mission is China’s first lunar sample return mission.It contains several new flight phases compared with the previous lunar missions,such as the lunar take-off and orbit insertion phase,the rendezvous and docking phase,etc.Chang’e-5 mission is extremely complicated and full of new challenges.This paper sorts out the characteristics and the difficulties in telemetry,tracking,and command(TT&C)of Chang’e-5 mission.The main technical contribution is a reliable general design of the TT&C system,including the application of X-band TT&C in launch and early orbit phase(LEOP),multiple targets simultaneous TT&C in X-band,lunar surface benchmark calibration,high-precision and rapid orbit trajectory determination for the lunar surface take-off,remote guidance rendezvous and docking,the determination of the initial navigational value for the separation point of the Chang’e-5 orbiter and returner,and the design of the reentry measurement chain.Based on this scheme,a global deep space TT&C network and interplanetary reentry measurement chain have been established for China,and near-continuous TT&C support for China’s first extraterrestrial object sampling and return mission has been realized,ensuring reliable tracking,accurate measurement and accurate control.The global deep space network can provide TT&C support comparable to that of National Aeronautics and Space Administration(NASA)and European Space Agency(ESA)for subsequent lunar and deep space exploration missions.The techniques of rapid trajectory determination of lunar take-off and orbit entry,as well as high precision and remote guidance of lunar orbit rendezvous and docking can lay a technological foundation for the future manned lunar exploration missions and planetary sampling and return missions. 展开更多
关键词 Chang’e-5 telemetry tracking and command(TT&C) the third phase of China lunar exploration program lunar exploration system design
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Isolation and Characterization of Heterotrophic Nitrifying Strain W1 被引量:5
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作者 吕永康 王荀 +2 位作者 刘博凯 刘玉香 杨晓华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期995-1002,共8页
In a high concentration substrate medium, a heterotrophic bacterium with high removal efficiency of ammonium, named W1, was isolated from activated sludge of coking wastewater treatment facility. The bacterium was Gra... In a high concentration substrate medium, a heterotrophic bacterium with high removal efficiency of ammonium, named W1, was isolated from activated sludge of coking wastewater treatment facility. The bacterium was Gram-negative, rod-shaped, and identified preliminarily as Alcaligenes sp. according to its morphological and physiological properties and its 16S rRNA gene sequence analysis. In the high concentration ammonium medium (400 mg·L 1 4 NH -N), the effects of C source, N source, C/N ratio and initial pH of medium on ammonium removal were investigated in order to determine the optimal condition for strain W1. The maximum ammonium removal was around 95% in 4 days in an improved medium. The production of N 2 gas was examined in a closed system that was full of pure oxygen at the beginning. N 2 gas was detected in the system after 4 days of cultivation, which further testified that strain W1 has heterotrophic nitrification and aerobic denitrification abilities simultaneously. 展开更多
关键词 heterotrophic nitrification aerobic de-nitrification high concentration ammonium Alcaligenes sp.
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Design and validation of wireless strain test system for bridge based on the resistance strain sensor
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作者 黄侨 李忠龙 +3 位作者 张连振 沙学军 徐玉滨 王德军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第1期18-23,共6页
In order to achieve an access to strain sensor data with wireless transmission in bridge engineering structure testing, a wireless strain test system is presented based on the resistance strain sensor of networks. The... In order to achieve an access to strain sensor data with wireless transmission in bridge engineering structure testing, a wireless strain test system is presented based on the resistance strain sensor of networks. The wireless bridge strain test system composed of master station and substation adopts the wireless method to realize the high accuracy data acquisition between the master station and the substation under a reliable communication protocol. The system has been tested in contrast with the present strain apparatus. Results show that the wireless system is high-reliable, and has many characteristics such as high efficiency, good precision, high stability with low cost, and good flexibility, without using the present communication network. 展开更多
关键词 wireless transmission bridge inspection data acquisition resistance strain sensor
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Performance Analysis of Uplink Distributed Massive MIMO System with Cross-Layer Design over Rayleigh Fading Channel 被引量:3
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作者 WANG Hui YU Xiangbin +2 位作者 LIU Fuyuan LIU Tao BAI Jiawei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第6期1028-1036,共9页
The performance of uplink distributed massive multiple-input multiple-output(MIMO)systems with crosslayer design(CLD) is investigated over Rayleigh fading channel, which combines the discrete rate adaptive modulation ... The performance of uplink distributed massive multiple-input multiple-output(MIMO)systems with crosslayer design(CLD) is investigated over Rayleigh fading channel, which combines the discrete rate adaptive modulation with truncated automatic repeat request. By means of the performance analysis, the closed-form expressions of average packet error rate(APER)and overall average spectral efficiency(ASE)of distributed massive MIMO systems with CLD are derived based on the conditional probability density function of each user’s approximate effective signal-to-noise ratio(SNR)and the switching thresholds under the target packet loss rate(PLR)constraint.With these results,using the approximation of complementary error functions,the approximate APER and overall ASE are also deduced. Simulation results illustrate that the obtained theoretical ASE and APER can match the corresponding simulations well. Besides,the target PLR requirement is satisfied,and the distributed massive MIMO systems offer an obvious performance gain over the co-located massive MIMO systems. 展开更多
关键词 distributed massive multiple-input multiple-output(MIMO)system zero-forcing detection cross-layer design spectral efficiency quality of service packet error rate
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Design and Implementation of Verification Code Identification Based on Anisotropic Heat Kernel 被引量:2
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作者 LIU Lizhao LIU Jian +3 位作者 DAI Yaomei XU Huarong YIN Huayi ZHU Shunzhi 《China Communications》 SCIE CSCD 2016年第1期100-112,共13页
Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as ... Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code manually.Improving the verification code security system needs the identification method as the corresponding testing system.We propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter set.Actual test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site. 展开更多
关键词 verification code image recognition data mining scale space anisotropic heat kernel
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LMI Approach to Mixed H_/H_∞ Fault Detection Observer Design 被引量:2
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作者 张迎春 吴丽娜 +1 位作者 李璟璟 陈雪芹 《Transactions of Tianjin University》 EI CAS 2012年第5期343-349,共7页
To investigate the robust fault detection (RFD) observer design for linear uncertain systems, the H_index and H∞ norm are used to describe this observer design as optimization problems. Conditions for the existence... To investigate the robust fault detection (RFD) observer design for linear uncertain systems, the H_index and H∞ norm are used to describe this observer design as optimization problems. Conditions for the existence of such a fault detection observer are given in terms of matrix inequalities. The solution is obtained by new iterative linear matrix inequality (ILMI) algorithms. The RFD observer design over finite frequency range in which Of does not have full column rank for a system is also considered. Numerical example demonstrates that the designed fault detection observer has high sensitivity to the fault and strong robustness to the unknown input. 展开更多
关键词 fault detection OBSERVER ROBUSTNESS sensitivity linear matrix inequality (LMI)
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Design of intelligent transformer monitoring system based on GSM 被引量:3
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作者 Kaiyuan Zheng 《International Journal of Technology Management》 2014年第1期35-37,共3页
This paper proposes a method for transformer fault detection system based on GSM network, through the current transformer, voltage sensor information, the known fault information attribute conditions, and the feedback... This paper proposes a method for transformer fault detection system based on GSM network, through the current transformer, voltage sensor information, the known fault information attribute conditions, and the feedback weighted coefficient through the adaptive feed forward, that can obtain high fault information attributes, thus filtering interference factors and timely get fault information properties. It solves the traditional transformer can only judge general fault and fault real-time alarm by GSM network, the system also can measure the transformer oil temperature and oil temperature alarm in super high temperature, to detect the power transformer operation parameters, and the fault running state (over-current, over-voltage, under-voltage, warning). The actual test system show that, diagnosis ability of fault signal separation ability and small signal identification increases 17%. also meet the requirements of real-time. 展开更多
关键词 TRANSFORMER fault detection: GSM real-time monitoring
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Design of EPS Testing System Based on LabVIEW2012
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作者 LIU Fang-gang LIU Xi 《International English Education Research》 2014年第5期62-64,共3页
The article designed a set of automatic test system of automobiles EPS based on LabVIEW, which can collect current signal and torque signal when emergency braking. It consists of two parts: hardware and software. Har... The article designed a set of automatic test system of automobiles EPS based on LabVIEW, which can collect current signal and torque signal when emergency braking. It consists of two parts: hardware and software. Hardware includes sensors,condition circuits, data acquisition card and your computer. Software-related programs, including an analysis of acquisition signal processing and storage display.The system is stable and reliable by contrast verification. 展开更多
关键词 signal acquisition EPS TEST SYSTEM LABVIEW
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Service Life Prediction and Management of Concrete Bridge Structures Due to Corrosion
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作者 Moe M. S. Cheung Kevin K. L. So 《Journal of Civil Engineering and Architecture》 2015年第10期1153-1166,共14页
The increasing stocks of public infrastructure and serious deterioration of infrastructure systems due to corrosion present great financial, safety, technical and operational challenges to government organizations in ... The increasing stocks of public infrastructure and serious deterioration of infrastructure systems due to corrosion present great financial, safety, technical and operational challenges to government organizations in charge of public infrastructure development and management. To meet those challenges, a performance-based life-cycle management model for reinforced concrete structures was proposed in this paper. This model predicts the life-cycle performance of infrastructure based on the corrosion-induced deterioration mechanism: condition index as well as performance limit states. A case study is provided to demonstrate the use of the proposed performance-based life-cycle cost management model. 展开更多
关键词 Concrete structure CORROSION DETERIORATION life-cycle management.
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