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On-line controlling system for nitrogen and phosphorus removal of municipal wastewater in a sequencing batch reactor (SBR) 被引量:2
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作者 Jun LI Yongjiong NI +5 位作者 Yongzhen PENG Guowei GU Jingen LU Su WEI Guobiao CHENG Changjin OU 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2008年第1期99-102,共4页
The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor(SBR).The SBR for municipal wastewate... The objectives of this study were to establish an on-line controlling system for nitrogen and phosphorus removal synchronously of municipal wastewater in a sequencing batch reactor(SBR).The SBR for municipal wastewater treatment was operated in sequences:filling,anaerobic,oxic,anoxic,oxic,settling and discharge.The reactor was equipped with on-line monitoring sensors for dissolved oxygen(DO),oxidation-reduction potential(ORP)and pH.The variation of DO,ORP and pH is relevant to each phase of biological process for nitrogen and phosphorus removal in this SBR.The characteristic points of DO,ORP and pH can be used to judge and control the stages of process that include:phosphate release by the turning points of ORP and pH;nitrification by the ammonia valley of pH and ammonia elbows of DO and ORP;denitrification by the nitrate knee of ORP and nitrate apex of pH;phosphate uptake by the turning point of pH;and residual organic carbon oxida-tion by the carbon elbows of DO and ORP.The controlling system can operate automatically for nitrogen and phosphorus efficiently removal. 展开更多
关键词 sequencing batch reactor(SBR) nitrogen and phosphorus removal dissolved oxygen(DO) oxidation-reduction potential(ORP) PH online control
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FREQUENCY-DOMAIN IMPLEMENTATION OF FILTERED-X ALGORITHMS WITH ON-LINE SYSTEM IDENTIFICATION FOR VIBRATION CONTROL
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作者 陈卫东 顾仲权 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期99-103,共5页
This paper describes the implementation of frequency-domain least mean squares (LMS) and Filtered-X algorithms and compares the performance of the frequencydomain adaptive control algorithm to a comparable timedomain ... This paper describes the implementation of frequency-domain least mean squares (LMS) and Filtered-X algorithms and compares the performance of the frequencydomain adaptive control algorithm to a comparable timedomain controller. When the frequency-domain LMS step size is allowed to vary as a function of frequency,the frequency-domain algorithm exhibits a better vibration reduction than the time-domain algorithm for the weaker frequencies in the energy spectrum. 展开更多
关键词 vibration reduction feedforward control adaptive filters vibration control adaptive algorithms
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Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms 被引量:6
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作者 杨彪 梁贵安 +5 位作者 彭金辉 郭胜惠 李玮 张世敏 李英伟 白松 《Journal of Central South University》 SCIE EI CAS 2013年第10期2685-2692,共8页
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and wi... The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design. 展开更多
关键词 industrial microwave DRYING ROTARY device SELF-ADAPTIVE PID controller genetic algorithm on-line tuning SELENIUM-ENRICHED SLAG
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Preoperative controlling nutritional status as an optimal prognostic nutritional index to predict the outcome for colorectal cancer 被引量:1
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作者 Li-Xiang Liu Hao Wang +6 位作者 Bo Gao Ting-Ting Xu Qing-Gang Yuan Shi-Zhen Zhou Chao Ding Ji Miao Wen-Xian Guan 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期343-353,共11页
BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT s... BACKGROUND The controlling nutritional status(CONUT)score effectively reflects a patient’s nutritional status,which is closely related to cancer prognosis.This study invest-igated the relationship between the CONUT score and prognosis after radical surgery for colorectal cancer,and compared the predictive ability of the CONUT score with other indexes.AIM To analyze the predictive performance of the CONUT score for the survival rate of colorectal cancer patients who underwent potentially curative resection.METHODS This retrospective analysis included 217 patients with newly diagnosed colorectal.The CONUT score was calculated based on the serum albumin level,total lymphocyte count,and total cholesterol level.The cutoff value of the CONUT score for predicting prognosis was 4 according to the Youden Index by the receiver operating characteristic curve.The associations between the CONUT score and the prognosis were performed using Kaplan-Meier curves and Cox regression analysis.RESULTS Using the cutoff value of the CONUT score,patients were stratified into CONUT low(n=189)and CONUT high groups(n=28).The CONUT high group had worse overall survival(OS)(P=0.013)and relapse-free survival(RFS)(P=0.015).The predictive performance of CONUT was superior to the modified Glasgow prognostic score,the prognostic nutritional index,and the neutrophil-to-lymphocyte ratio.Meanwhile,the predictive performances of CONUT+tumor node metastasis(TNM)stage for 3-year OS[area under the receiver operating characteristics curve(AUC)=0.803]and 3-year RFS(AUC=0.752)were no less than skeletal muscle mass index(SMI)+TNM stage.The CONUT score was negatively correlated with SMI(P<0.01).CONCLUSION As a nutritional indicator,the CONUT score could predict long-term outcomes after radical surgery for colorectal cancer,and its predictive ability was superior to other indexes.The correlation between the CONUT score and skeletal muscle may be one of the factors that play a predictive role. 展开更多
关键词 controlling nutritional status Colorectal cancer Prognostic marker SARCOPENIA Skeletal muscle
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Modeling of Microstructure Evolution and Mechanical Properties of Steel Plates Produced by Thermo-Mechanical Control Process and Its On-line Application 被引量:1
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作者 Yunbo XU, Yongmei YU, Xianghua LIU and Guodong WANGState Key Laboratory of Rolling Technology and Automation, Northeastern University, P.O. Box 105, Shenyang 110004, ChinaPh.D., 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第1期13-16,共4页
An integrated metallurgical model was developed to predict microstructure evolution and mechanical properties of low-carbon steel plates produced by TMCP. The metallurgical phenomena occurring during TMCP and mechanic... An integrated metallurgical model was developed to predict microstructure evolution and mechanical properties of low-carbon steel plates produced by TMCP. The metallurgical phenomena occurring during TMCP and mechanical properties were predicted for different process parameters. In the later passes full recrystallization becomes difficult to occur and higher residual strain remains in austenite after rolling. For the reasonable temperature and cooling schedule, yield strength of 30 mm plain carbon steel plate can reach 310 MPa. The first on-line application of prediction and control of microstructure and properties (PCMP) in the medium plate production was achieved. The predictions of the system are in good agreement with measurements. 展开更多
关键词 Thermo-mechanical control process Metallurgical model Low-carbon steel Prediction and control of microstructure and properties on-line application
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STRONGLY CONVERGENT INERTIAL FORWARD-BACKWARD-FORWARD ALGORITHM WITHOUT ON-LINE RULE FOR VARIATIONAL INEQUALITIES
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作者 姚永红 Abubakar ADAMU Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期551-566,共16页
This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inerti... This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inertial parameters and the iterates,which have been assumed by several authors whenever a strongly convergent algorithm with an inertial extrapolation step is proposed for a variational inequality problem.Consequently,our proof arguments are different from what is obtainable in the relevant literature.Finally,we give numerical tests to confirm the theoretical analysis and show that our proposed algorithm is superior to related ones in the literature. 展开更多
关键词 forward-backward-forward algorithm inertial extrapolation variational inequality on-line rule
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DCS devices based non-linear process control system design for plants with distributed time-delay using particle filter 被引量:3
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作者 DENG Ming-cong FUJII Ryohei 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3351-3358,共8页
Remote control process system with distributed time-delay has attracted much attention in different fields.In this paper,non-linear remote control of a single tank process system with wireless network is considered.To... Remote control process system with distributed time-delay has attracted much attention in different fields.In this paper,non-linear remote control of a single tank process system with wireless network is considered.To deal with the distributed time-delay in a large-scale plant,the time-delay compensation controller based on DCS devices is designed by using operator theory and particle filter.Distributed control system(DCS)device is developed to monitor and control from the central monitoring room to each process.The particle filter is a probabilistic method to estimate unobservable information from observable information.First,remote control system and experimental equipment are introduced.Second,control system based on an operator theory is designed.Then,process system with distributed time-delay using particle filter is carried out.Finally,the actual experiment is conducted by using the proposed time-delay compensation controller.When estimating with the proposed method,the result is close to the case in which the distributed time-delay does not exist.The effectiveness of the proposed control system is confirmed by experiment results. 展开更多
关键词 non-linear remote control distributed control system particle filter operator theory distributed time-delay
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A New Strategy of Integrated Control and On-line Optimization on High-purity Distillation Process 被引量:10
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作者 吕文祥 朱鹰 +2 位作者 黄德先 江永亨 金以慧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期66-79,共14页
For high-purity distillation processes,it is difficult to achieve a good direct product quality control using traditional proportional-integral-differential(PID)control or multivariable predictive control technique du... For high-purity distillation processes,it is difficult to achieve a good direct product quality control using traditional proportional-integral-differential(PID)control or multivariable predictive control technique due to some difficulties,such as long response time,many un-measurable disturbances,and the reliability and precision issues of product quality soft-sensors.In this paper,based on the first principle analysis and dynamic simulation of a distillation process,a new predictive control scheme is proposed by using the split ratio of distillate flow rate to that of bottoms as an essential controlled variable.Correspondingly,a new strategy with integrated control and on-line optimization is developed,which consists of model predictive control of the split ratio,surrogate model based on radial basis function neural network for optimization,and modified differential evolution optimization algorithm. With the strategy,the process achieves its steady state quickly,so more profit can be obtained.The proposed strategy has been successfully applied to a gas separation plant for more than three years,which shows that the strategy is feasible and effective. 展开更多
关键词 distillation process control split ratio surrogate model optimization modified differential evolution
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Controlling the dynamic behavior of decentralized cluster through centralized approaches
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作者 袁大明 王培龙 +6 位作者 王鹏 马星宇 汪楚云 王璟 陈怀城 王高 叶方富 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期46-54,共9页
How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation... How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems. 展开更多
关键词 self-organizing system centralized control dynamics regulation
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Gypsum-based Silica Gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance
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作者 李曦 冉茂宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期337-344,共8页
Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based compos... Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and proportion.The morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and analyzed.The experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure increase.The absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel proportion.When 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of pure-gypsum.The moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,respectively.The gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions. 展开更多
关键词 humidity controlling composite materials GYPSUM silica gel
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Transient Stability Improvement of Power System Using Non-Linear Controllers 被引量:1
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作者 Rekha Chaudhary Arun Kumar Singh 《Energy and Power Engineering》 2014年第1期10-16,共7页
This paper presents the design of a non-linear controller to prevent an electric power system losing synchronism after a large sudden fault and to achieve good post fault voltage level. By Direct Feedback Linearizatio... This paper presents the design of a non-linear controller to prevent an electric power system losing synchronism after a large sudden fault and to achieve good post fault voltage level. By Direct Feedback Linearization (DFL) technique robust non-linear excitation controller is designed which will achieve stability enhancement and voltage regulation of power system. By utilizing this technique, there is a possibility of selecting various control loops for a particular application problem. This method plays an important role in control system and power system engineering problem where all relevant variables cannot be directly measured. Simulated results carried out on a single machine infinite bus power system model which shows the enhancement of transient stability regardless of the fault and changes in network parameters. 展开更多
关键词 Single Machine INFINITE Bus (SMIB) Direct Feedback LINEARIZATION (DFL) Fuzzy Logic controller (FLC) SLIDING Mode control (SMC)
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Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin
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作者 Xu Zeng Tao Yang +5 位作者 Jian-Wei Feng Cong-Sheng Bian Ming Guan Wei Liu Bing-Cheng Guo Jin Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期791-805,共15页
Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fra... Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in these areas when structural fractures are present and the source, and storage spaces are separated. 展开更多
关键词 FRACTURES Development characteristics controlling factors Shale oil Sweet spot
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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On-line current feed and computer aided control tactics for automatic balancing head
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作者 李勇 陆永平 +1 位作者 须根发 夏松波 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期205-207,共3页
In the designed automatic balancing head, a non contact induction transformer is used to deliver driving energy to solve the problem of current fed and controlling on line. Computer controlled automatic balancing expe... In the designed automatic balancing head, a non contact induction transformer is used to deliver driving energy to solve the problem of current fed and controlling on line. Computer controlled automatic balancing experiments with phase magnitude control tactics were performed on a flexible rotor system. Results of the experiments prove that the energy feeding method and the control tactics are effective in the automatic balancing head for vibration controlling. 展开更多
关键词 AUTOMATIC balancing balancing HEAD on-line control TACTICS
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Load Frequency Control of Small Hydropower Plants Using One-Input Fuzzy PI Controller with Linear and Non-Linear Plant Model 被引量:2
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作者 Derek Ajesam Asoh Edwin Nyuysever Mbinkar Albert Nouck Moutlen 《Smart Grid and Renewable Energy》 2022年第1期1-16,共16页
<span style="font-family:Verdana;">This study presents an intelligent approach for load frequency control (LFC) of small hydropower plants (SHPs). The approach which is based on fuzzy logic (FL), takes... <span style="font-family:Verdana;">This study presents an intelligent approach for load frequency control (LFC) of small hydropower plants (SHPs). The approach which is based on fuzzy logic (FL), takes into account the non-linearity of SHPs—something which is not possible using traditional controllers. Most intelligent methods use two-</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">input fuzzy controllers, but because such controllers are expensive, there is </span><span style="font-family:Verdana;">economic interest in the relatively cheaper single-input controllers. A n</span><span style="font-family:Verdana;">on-</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">linear control model based on one-input fuzzy logic PI (FLPI) controller was developed and applied to control the non-linear SHP. Using MATLAB/Si</span><span style="font-family:Verdana;">- </span><span style="font-family:Verdana;">mulink SimScape, the SHP was simulated with linear and non-linear plant models. The performance of the FLPI controller was investigated and compared with that of the conventional PI/PID controller. Results show that the settling time for the FLPI controller is about 8 times shorter;while the overshoot is about 15 times smaller compared to the conventional PI/PID controller. Therefore, the FLPI controller performs better than the conventional PI/PID controller not only in meeting the LFC control objective but also in ensuring increased dynamic stability of SHPs.</span> 展开更多
关键词 Small Hydropower Plant Linear and Non-linear Model Load Frequency control Non-linear control Fuzzy Logic controller Renewable Energy
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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China
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作者 Gang Li Xian-Ming Xiao +3 位作者 Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1488-1507,共20页
The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not w... The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well understood.In the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed.The results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM pores.The pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,respectively.The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,respectively.Compared with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption capacity.The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas potential.Considering the geological and geochemical conditions of shale gas formation and preservation,the deep-water shelf facies is the most favorable target for the Lower Cambrian shale gas exploration and development in the western Hubei area,South China. 展开更多
关键词 Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content controlling factor
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Application of on-line quality control for salvianolic acid B by near infrared spectroscopy
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作者 Jin-Wei Zhang Yan Liu +1 位作者 Wei-Wei Liu Yan-Ying Zhang 《Health》 2009年第3期244-248,共5页
OBJECTIVE: To study and establish quality con-trol model of the Salvianolic Acid B by Near In-frared Spectroscopy (NIRS), and to realize on-line quality control of extracting and purifying proc-esses of industrial sca... OBJECTIVE: To study and establish quality con-trol model of the Salvianolic Acid B by Near In-frared Spectroscopy (NIRS), and to realize on-line quality control of extracting and purifying proc-esses of industrial scale herbal product manu-facturing. METHOD: NIR chromatography was obtained from on-line NIR detection of extract-ing process and purifying process. HPLC analysis was carried out to determine the con-tents of salvianolic acid B. Partial Least Squares Regression (PLS) was used to establish the model between the information between NIRS and HPLC. RESULTS: For extracting model: the optimum Near Infrared (NIR) wavelength range was 9815- 5430cm-1, R=0.9784, RMSEC=0.258;for puri-fying model: the optimum NIR wavelength range was 9815-5430cm-1, R=0.9776, RMSEC=4.02. The average relative error was <5%. CONCLUSION: NIR technique is applicable for on-line quality control in production of salvianolic acid B. 展开更多
关键词 NIR Salvianolic ACID B on-line QUALITY control INDUSTRIAL SCALE
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Hybrid Q-learning for data-based optimal control of non-linear switching system 被引量:1
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作者 LI Xiaofeng DONG Lu SUN Changyin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第5期1186-1194,共9页
In this paper,the optimal control of non-linear switching system is investigated without knowing the system dynamics.First,the Hamilton-Jacobi-Bellman(HJB)equation is derived with the consideration of hybrid action sp... In this paper,the optimal control of non-linear switching system is investigated without knowing the system dynamics.First,the Hamilton-Jacobi-Bellman(HJB)equation is derived with the consideration of hybrid action space.Then,a novel data-based hybrid Q-learning(HQL)algorithm is proposed to find the optimal solution in an iterative manner.In addition,the theoretical analysis is provided to illustrate the convergence and optimality of the proposed algorithm.Finally,the algorithm is implemented with the actor-critic(AC)structure,and two linear-in-parameter neural networks are utilized to approximate the functions.Simulation results validate the effectiveness of the data-driven method. 展开更多
关键词 switching system hybrid action space optimal control reinforcement learning hybrid Q-learning(HQL)
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Spatial-temporal heterogeneity and controlling factors of evapotranspiration in Nujiang River Basin based on Variable Infiltration Capacity(VIC)model
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作者 ZHANG Xianhe LIU Shiyin +1 位作者 ZHU Yu XIE Fuming 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3598-3614,共17页
Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by la... Land surface evapotranspiration(ET)is a critical component in the hydrological cycle but has not well been understood in data-scarce areas especially in river basins,like Nujiang River(NRB)which is characterized by large elevation gradient and different vegetation zones with complex processes of water and energy exchange.The quality of ET from optical remote sensing is constrained by cloud cover which is common in the NRB in the monsoon seasons.To understand factors controlling the spatial-temporal heterogeneity of ET in NRB,we employed the Variable Infiltration Capacity(VIC)hydrological model by parameter optimization with support of quality controlled remote sensing ET product and observed river runoff series in the river.The modeled ET has increased during 1984-2018,which might be one of the reasons for the runoff decrease but precipitation increase in the same period.ET increase and runoff decrease tended to be quicker within altitudinal band of 2000-4000 m than in other areas in NRB.We observed that ET variation in different climatic zones were controlled by different factors.ET is generally positively correlated with precipitation,temperature,and shortwave radiation but negatively with relative humidity.In the Tundra Climate(Et)zone in the upper reach of NRB,ET is controlled by precipitation,while it is controlled by shortwave radiation in the snow climate with dry winter(Dw)zone.ET increase is influenced by the increase of temperature,wind speed,and shortwave radiation in the middle and downstream of NRB with warm temperate climate,fully humid(Cf)and warm temperate climate with dry winter(Cw). 展开更多
关键词 EVAPOTRANSPIRATION Variable infiltration capacity(VIC)model Spatial temporal heterogeneity Climate change controlling factors Nujiang River Basin
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Development and application of ocean station auto monitoring data on-line quality control system
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作者 WANG Qisong FANG Shulin +1 位作者 YIN Danni ZHAO Yueru 《Marine Science Bulletin》 2021年第1期71-79,共9页
The quality control of ocean observation data is conducted by monthly review,yet no on-line quality control system is deployed.An on-line quality control system is provided by this article.The threshold of extreme and... The quality control of ocean observation data is conducted by monthly review,yet no on-line quality control system is deployed.An on-line quality control system is provided by this article.The threshold of extreme and rate of change is created by analyzing the character of observation items.The alert will be triggered to remind the operator if the system detects data out of threshold.therefore the on-line data quality control is accomplished. 展开更多
关键词 ocean station DATA on-line quality control
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