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不同苹果种质收集系对火疫病的田间抗性
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作者 JamesJ.Luby 谢国禄 《国外作物育种》 2003年第1期63-63,共1页
关键词 苹果 种质收集系 火疫病 田间抗性
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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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生活垃圾填埋场环境影响评价
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作者 童文修 《低碳世界》 2013年第07X期183-184,共2页
文章分析了城市生活垃圾填埋场气体的生成、气体生成的因素、特性。探讨了城市生活垃圾填埋场填埋场气的收集系统,采取措施填埋场废气的处理对污染控制,并讨论了生活垃圾渗透液对地下水质影响分析等问题。
关键词 填埋气 收集系 防渗
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Comparison of Absorption Capacity of Different Flue-cured Tobacco Cultivars for Six Kinds of Heavy Metals 被引量:1
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作者 曾维爱 李帆 +3 位作者 谭琳 蔡海林 黄艳宁 胡秋龙 《Agricultural Science & Technology》 CAS 2016年第9期2081-2084,共4页
[Objective] This study aimed to analyze the differences in absorption capacity of different flue-cured tobacco cultivars for chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg) and copper (Cu... [Objective] This study aimed to analyze the differences in absorption capacity of different flue-cured tobacco cultivars for chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg) and copper (Cu). [Method] With 4 flue-cured tobacco cultivars as the experimental materials, their absorption capacity for 6 kinds of heavy metals was compared by pot experiment. [Result] There were great differences in absorption capacity of different flue-cured tobacco cultivars for the six kinds of heavy metals. According to the absorption capacity of different flue-cured tobacco cultivars for the heavy metals, the six heavy metals could be classified into three categories. The first category included only Cd with average enrichment coefficient of 8.564; the second category included Hg with average enrichment coefficient of 0.753; and the third category included Cr, As, Pb and Cu with average enrichment coefficients below or equivalent to 0.114. [Conclusion] The absorption capacity of different flue-cured tobacco cultivars for heavy metals was grasped by this study, thereby providing reference data for screening of high-yielding and high-quality flue-cured tobacco cultivars. 展开更多
关键词 Flue-cured tobacco cultivar Heavy metal Enrichment coefficient Absorption capacity
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Household model of rainwater harvesting system in Mexican urban zones 被引量:1
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作者 José A.Gleason-Espíndola 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期175-180,共6页
This paper describes a household model of the rainwater harvesting system in residential development of Tlaquepaque Jalisco Mexico. Harvested rainwater is estimated for designing a rainwater catchment system which ref... This paper describes a household model of the rainwater harvesting system in residential development of Tlaquepaque Jalisco Mexico. Harvested rainwater is estimated for designing a rainwater catchment system which reflects the maximum water supply to a household.Based on the estimation of the harvested rainwater the total water demand is calculated in order to explore the possible uses of rainwater. Major components in the rainwater catchment system are as follows catchment area downspout roof drain pipe and first flush tank cistern infiltration well pumping station and filtering system and ultraviolet UV water treatment.The rainwater harvesting system is designed to operate as the part of the central water supply system.This paper exposes the process of design and construction and its cost.In this way it aims to establish a technical and conceptual reference which enables the citizens to design their rainwater systems and their construction. This model will produce an important experience that can help to improve the systems in a Mexican context.It can be also useful for the international community. 展开更多
关键词 rainwater harvesting system water supply water demand catchment area cistern
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Data Reconstruction in Internet Traffic Matrix 被引量:1
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作者 ZHOU Huibin ZHANG Dafang XIE Kun WANG Xiaoyang 《China Communications》 SCIE CSCD 2014年第7期1-12,共12页
Traffic matrix is an abstract representation of the traffic volume flowing between sets of source and destination pairs.It is a key input parameter of network operations management,planning,provisioning and traffic en... Traffic matrix is an abstract representation of the traffic volume flowing between sets of source and destination pairs.It is a key input parameter of network operations management,planning,provisioning and traffic engineering.Traffic matrix is also important in the context of OpenFlow-based networks.Because even good measurement systems can suffer from errors and data collection systems can fail,missing values are common.Existing matrix completion methods do not consider traffic exhibit characteristics and only provide a finite precision.To address this problem,this paper proposes a novel approach based on compressive sensing and traffic self-similarity to reconstruct the missing traffic flow data.Firstly,we analyze the realworld traffic matrix,which all exhibit lowrank structure,temporal smoothness feature and spatial self-similarity.Then,we propose Self-Similarity and Temporal Compressive Sensing(SSTCS) algorithm to reconstruct the missing traffic data.The extensive experiments with the real-world traffic matrix show that our proposed SSTCS can significantly reduce data reconstruction errors and achieve satisfactory accuracy comparing with the existing solutions.Typically SSTCS can successfully reconstruct the traffic matrix with less than 32%errors when as much as98%of the data is missing. 展开更多
关键词 network measurement trafficmatrix compressive sensing matrixcompletion SELF-SIMILARITY
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Water Resource Management and Its Role in Development of Integrated Mountainous Agriculture——A Case from Ningnan County of Sichuan Province 被引量:1
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作者 ZHA0 Liu-hui WU Yang 《Agricultural Science & Technology》 CAS 2010年第8期183-188,共6页
This paper reviewed rainwater collection and water resource management in Ningnan County in southwestern mountain of China,as a case study for solving the problems of water management in a simple and sustainable way. ... This paper reviewed rainwater collection and water resource management in Ningnan County in southwestern mountain of China,as a case study for solving the problems of water management in a simple and sustainable way. In this mountainous agriculture system,private agricultural enterprises were introduced into local mountain agriculture to solve capital fund shortage for the construction of rainwater harvesting system. Agreement was signed by private agriculture enterprises with the target farmers to subscribe for the household agriculture production at a protection price. Cash invested by the enterprise and subsidy from the government were collected for purchasing materials,while the farmers supplied labors for the construction of water harvesting systems. The system solved the share of input and benefits between the local government,enterprise and household farms successfully. In addition,the micro water harvesting tanks and micro irrigate systems extend quickly in this mountainous county. Up to 2007,more than 12 000 rainwater harvesting tanks had been established and more than 8.5×104 hm2 dry arable land accounting for nearly 75% of the total arable land had been irrigated efficiently. Per capita income of farmer had been increased by 14 times in the past 20 years. Considerable potential for further improvement in implementation of the models for solving water shortage and water resource management in mountain region maybe depend on more local private agriculture enterprises and households than the government. 展开更多
关键词 Water resource management Rainfed agriculture Mountain region Water harvesting
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Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm 被引量:7
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作者 青松 唐军武 +1 位作者 崔廷伟 张杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期33-45,共13页
We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coef... We tested and modified the quasi-analytical algorithm (QAA) using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference (APD) is in a range of 13.9%-38.5% for the total absorption coefficient (13.9% at 440 nm), and differences in particle backscattering coefficient bbp(2) are less than 50% (in the case of the updated QAA). To obtain improved results, we modified the QAA by adjusting the empirical relationships. The modified algorithm is then applied to the field data to test its performance. The APDs were 44.7%-46.6% for bbp(λ) and 9.9%-32.8% (9.9% at 555 nm) for the total absorption coefficient. This indicates that the modified QAA derives better results. We also used the modified model to derive phytoplankton pigment absorption (aph) and detritus and CDOM absorption (aug) coefficients. The APDs for aph and a dg at 440 nm are 37.1% and 19.8%. In this paper, we discuss error sources using the measured dataset. More independent field data can improve this algorithm and derive better results. 展开更多
关键词 inherent optical properties Yellow Sea and the East China Sea quasi-analytical algorithm
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Network Intelligence Capability Requirements and Standards System 被引量:2
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作者 Wang Qian Zhang Yuan Zhao Huiling 《China Standardization》 2012年第4期84-85,共2页
It is discussed in this paper the capability requirements of modern communication industry for smart pipe or Network Intelligence Capability Enhancement (NICE), Domestic and international researches on smart pipe ar... It is discussed in this paper the capability requirements of modern communication industry for smart pipe or Network Intelligence Capability Enhancement (NICE), Domestic and international researches on smart pipe are elaborated in the essay as well. 展开更多
关键词 Smart pipe function STANDARD
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Rainwater Harvesting in Multifamily Social Interest Housing
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作者 Regina Lucia Melo de Oliveira Marilia Karla da Silva Santos Simone Rosa da Silva 《Journal of Civil Engineering and Architecture》 2015年第10期1261-1268,共8页
This study evaluated the reduction of water consumption in a SIH (social interest housing) complex from the simulation of implanting a rainwater harvesting system. The methodology consisted of characterization of th... This study evaluated the reduction of water consumption in a SIH (social interest housing) complex from the simulation of implanting a rainwater harvesting system. The methodology consisted of characterization of the case study, survey data of water consumption and data of precipitation in the area, on-site visits to define the average consumption and monthly water distribution, and sizing of a rainwater harvesting tank following the Netuno Program. It was obtained 22.500 L as the ideal volume for the tank, supplying the demand for drinkingwater in 32%, although the reduction in the drinking water bills would be minor, since the object of the case study is considered SIH, and residents pay a fixed fee for consuming up to 10 m3 per month. Therefore, it becomes necessary to analyze this situation from a sustainable and environmental perspective, and the benefits are no longer only economic, but rather they take on a more comprehensive social dimension. 展开更多
关键词 Rational use of water rainwater harvesting rainwater collection social interest housing.
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Use of Multi-criteria Decision Analysis Methods for Water Supply Problems: A Framework for Improved Rainwater Harvesting
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作者 Omolara Lade David Oloke Ezekiel Chinyio Michael Fullen 《Journal of Environmental Science and Engineering(A)》 2012年第7期909-917,共9页
Several conflicting objectives are considered in decision-making. MCDA (multi-criteria decision analysis) methods are developed to facilitate better decision making by decision-makers. Water supply problems are comp... Several conflicting objectives are considered in decision-making. MCDA (multi-criteria decision analysis) methods are developed to facilitate better decision making by decision-makers. Water supply problems are complex problems with multiple decision making and criteria. Hence, the use of multi-criteria decision analysis is very appropriate for solving these problems. Multi-criteria decision analysis can be divided into three main groups: value measurement models, goals, aspiration and reference level models and outranking models. The methods listed have been applied to water supply problems, especially in the evaluation of alternative water supply strategies. Each method has its advantages and limitations. A good alternative for concluding a better-suited method for water supply problems is to apply more than one method, either in combination to make use of the strengths of both methods, or in parallel to obtain a broader decision basis for the decision maker. Previous studies of MCDA in water supply planning have usually considered water supply networks with only one water service delivery. Advanced water supply sources with multiple water service delivery systems have been neglected. This is an on-going study in which analytical hierarchical multi-criteria decision analysis methods are proposed for solving water supply problems and a framework for improved rainwater harvesting systems will be developed. 展开更多
关键词 Water supply multiple-criteria decision analysis sustainability.
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A Proposal for Reservoir Volume Calculation in Rainwater Harvesting Systems
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作者 Rodrigo Braga Moruzzi Marcelo Loureiro Garcia Samuel Conceicao de Oliveira 《Journal of Civil Engineering and Architecture》 2012年第6期707-714,共8页
This paper introduces a proposal for reservoir volume calculation in rainwater harvesting systems. The proposed method can be used for reservoir volume design in rainwater harvesting systems and is based on three impo... This paper introduces a proposal for reservoir volume calculation in rainwater harvesting systems. The proposed method can be used for reservoir volume design in rainwater harvesting systems and is based on three important variables. These variables are water demand, system efficiency and repayment time. Several simulations were carried out in different scenarios considering typical values of both catchment area (for low-income and medium-income households) and water demand, with fixed water and tank costs. Results showed that the integrated analysis of demand, efficiency and repayment time may assist designers to determine a more adequate reservoir volume. 展开更多
关键词 Rainwater use reservoir volume design criteria.
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Worldwide or Territorial Approach for Individual Income Tax, Which is More Prevalent? 被引量:1
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作者 Connie Shum Jack Fay Gladie Lui 《Journal of Modern Accounting and Auditing》 2017年第4期137-151,共15页
For individuals who are contemplating relocating, how their income will be taxed might be an important factor when deciding whether or not to take up residence in another country. Two income approaches are commonly us... For individuals who are contemplating relocating, how their income will be taxed might be an important factor when deciding whether or not to take up residence in another country. Two income approaches are commonly used around the globe. Worldwide income approach (also known as a global tax system) taxes income from whatever source derived. Territorial income approach taxes only income earned within the country's borders. Using information collected from PricewaterhouseCoopers' website1 that provides information on tax systems used in countries around the world, this paper examines which countries apply worldwide or global income approach and which employ territorial approach to determine the legitimate source of taxable income. The research focuses on countries within: (1) Americas; (2) Asia/Pacific Basin; (3) Europe; and (4) Africa/Middle and Near East. Based on the information collected and presented in this paper, the worldwide approach is much more prevalent (104 countries) than the territorial approach (30 countries). This paper also investigates any specific rules that a particular country has in relation to income to be taxed and residency versus non-residency status of the taxpayers. There appears to be an abundant spectrum of rules relating to residency and domicile for tax purposes among the countries. 展开更多
关键词 individual income tax global individual income tax worldwide/territorial income approach
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Developments of solar collectors in China
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作者 Yin Zhiqiang 《Engineering Sciences》 EI 2009年第2期80-85,共6页
China has abundant solar energy resource. Solar thermal collectors, particularly all-glass evacuated tubular collectors, have been studied and developed for 30 years, and solar thermal industry has developed rapidly f... China has abundant solar energy resource. Solar thermal collectors, particularly all-glass evacuated tubular collectors, have been studied and developed for 30 years, and solar thermal industry has developed rapidly for 15 years. There are various solar thermal systems, with an operation area of around 108 million m2 in 2007. These systems mainly provide domestic hot water, but some other applications are under extensive study and development as well. 展开更多
关键词 solar collector domestic hot water flat plate collector all-glass evacuated collector tube all-glass evacuated tube collector glass-metal evacuated tube collector
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Energy Efficiency Optimization in Relay-Assisted Networks with Energy Harvesting Relay Constraints 被引量:5
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作者 ZHAO Ming ZHAO Jing +2 位作者 ZHOU Wuyang ZHU Jinkang ZHANG Sihai 《China Communications》 SCIE CSCD 2015年第2期84-94,共11页
In this paper we consider data transmission in a decode-and-forward(DF)relay-assisted network in which the relay is energy harvesting(EH) powered while the base station(BS) is power-grid powered.Our purpose is to maxi... In this paper we consider data transmission in a decode-and-forward(DF)relay-assisted network in which the relay is energy harvesting(EH) powered while the base station(BS) is power-grid powered.Our purpose is to maximize the BS's energy efficiency(EE) while making full use of the relay's renewable energy and satisfying the specific average throughput requirements.In contrast to existing literature on energy harvesting system which only considers the radio transmission power,we take the static circuit power into account as well.We formulate the EE optimization problem and prove that the EE of the BS and relay are both quasiconvex in the instantaneous transmission rate.Then we divide the complex optimization problem into two point-to-point link level optimization parts and propose an energyefficient resource allocation(EERA) scheme in which power control and sleep mode management are jointly used.The simulation results demonstrate that EERA may achieve good energy saving effects.We also compare the EE of an energy harvesting relay system with a power-grid powered one and provide more insight into the EE problem of energy harvesting relay system. 展开更多
关键词 energy efficiency energy harvesting relay sleep mode
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Management Procedures for Data Collected via Intelligent Transportation Systems
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作者 Qiang Hong Richard Wallace +3 位作者 Eric Dennis Brian Reed William Tansil Matt Smith 《Journal of Civil Engineering and Architecture》 2015年第9期1069-1078,共10页
Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS (intelligent transportation systems) and CV (connected veh... Addressing transportation planning, operation and investment challenges requires increasingly sophisticated data and information management strategies. ITS (intelligent transportation systems) and CV (connected vehicle) technologies represent a new approach to capturing and using needed transportation data in real time or near real time. In the case of Michigan, several ITS programs have been launched successfully, but independently of each other. The objective of this research is to evaluate and assess all important factors that will influence the collection, management and use of ITS data, and recommend strategies to develop integrated, dynamic and adaptive data management systems for state transportation agencies. 展开更多
关键词 ITS connected vehicle technology transportation data management state transportation agency.
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MPPT research based on fuzzy adaptive PID control 被引量:1
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作者 张开如 潘安琪 初雪娇 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期389-392,共4页
In order to improve the efficiency and precision of maximum power point tracking(MPPT)control,a new method is proposed.Based on original MPPT technology of photovoltaic cells,the fuzzy adaptive proportion-integral-dif... In order to improve the efficiency and precision of maximum power point tracking(MPPT)control,a new method is proposed.Based on original MPPT technology of photovoltaic cells,the fuzzy adaptive proportion-integral-differential(PID)control has less fluctuation and higher stability.The simulation circuit using Simulink is established,and output power curves under constant temperature or constant sunlight are obtained.The superiority of the fuzzy PID control method has been proved by means of the simulation results,and it makes the solar system approach maximum power point quickly and smoothly. 展开更多
关键词 photovoltaic cells fuzzy proportion-integral-differential(PID) maximum power point tracking(MPPT) SIMULINK
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Object-tracking robot using ultrasonic sensor and servo motor 被引量:1
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作者 Kyounghwan Kim Hyunseop Lim +1 位作者 Yoseop Hwang Jangmyung Lee 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期379-382,共4页
This paper proposes a method that rotation angle of servo motor and distance values of ultrasonic sensor are used for tracking an object in real-time while the robot keeps regular distance.Object detection distance wi... This paper proposes a method that rotation angle of servo motor and distance values of ultrasonic sensor are used for tracking an object in real-time while the robot keeps regular distance.Object detection distance widens by using ultrasonic sensors and object recognition,and movement of robot is controlled by angle of servo motor and distance of ultrasonic sensors.Not adopting the existing tracking methods:camera,laser-infrared(LRF)and many ultrasonic sensors,the proposed method proves that it is possible to track object using ultrasonic sensor and servo motor.Trajectory of robot is represented and analysed according to movement of object in limited conditions. 展开更多
关键词 tracking robot ultrasonic sensor servo motor mobile robot
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New WA-system of kravchenko functions in digital signal processing 被引量:1
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作者 V F Kravchenko D V Churikov 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期345-351,共7页
On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.Th... On the basis of modified atomic transformations the new WA-systems of Kravchenko functions are constructed.As an example the digital processing of time series of the various physical nature processing is considered.The numerical experiments and physical analysis of the results confirm the efficiency of the proposed WA-systems of Kravchenko functions. 展开更多
关键词 atomic functions WA-systems of functions WAVELETS digital signal processing(DSP)
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Model Predictive Control with Feedforward Strategy for Gas Collectors of Coke Ovens 被引量:2
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作者 李凯 李德伟 +1 位作者 席裕庚 尹德斌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期769-773,共5页
In coking process, the production quality, equipment life, energy consumption, and process safety are all influenced by the pressure in gas collector pipe of coke oven, which is frequently influenced by disturbances.T... In coking process, the production quality, equipment life, energy consumption, and process safety are all influenced by the pressure in gas collector pipe of coke oven, which is frequently influenced by disturbances.The main control objectives for the gas collector pressure system are keeping the pressures in collector pipes at appropriate operating point. In this paper, model predictive control(MPC) strategy is introduced to control the collector pressure system due to its ability to handle constraint and good control performance. Based on a method proposed to simplify the system model, an extended state space model predictive control is designed,which combines the feedforward strategy to eliminate the disturbance. The simulation results in a system with two coke ovens show the feasibility and effectiveness of the control scheme. 展开更多
关键词 Gas collector pressure system Model predictive control FEEDFORWARD
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