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| 1 | Impact chaos control and stress release——A key for development of ultra fine vibration milling显示文摘Through our previous experimental and analytical studies, it has been discovered that the key for the development of vibration milling is the impact chaos control and stress release. The necessities for the chaos control and stress release are: (i) to strictly eliminate the sub-harmonics; (ii) to control the super-harmonics to a lower level and (iii) to load the system compressively with relatively higher period, in order that the vibration energy can be absorbed by the particles effectively and sufficiently. A new vibration model for ultra fine milling is proposed, which has wide applications in preparing ultra fine particles. | WANG Shulin(Department of Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China) | 2002 | Progress in Natural Science:Materials International2002，12，5： | 40 |
| 2 | Air pollutants contribution and control strategies of energy-use related sources in Beijing显示文摘Based on the statistical analysis of emission inventory and ISCST3 model simulation, the emission and ambient concentration contributions of energy-use related sources to the major pollutants of SO2, NOx and PM10 in urban areas of Beijing were analyzed. The SO2 emission contributions of coal burning in power plants, industrial and heating sectors were 49%, 26% and 24% respectively. The vehicle exhaust contributed 74% of the NOx concentration. As to PM10, the industrial sector was the largest emission (28%) and concentration (21%) contributor despite of the fugitive sources. The source emission contributions of VOC and NH3, which greatly influence the generation of secondary pollutants, were discussed as well. This paper also analyzed the control strategies of energy consumption and vehicle sources, based on which the control scenario in 2008 was established and the change of emission and concentration contribution were estimated. The results show that the cleaner energy use, industrial structure improvement, transportation mode modification and single vehicle emission control will greatly improve air quality. The industrial sector will change to the largest contributor of SO2 and as to NOx, vehicle emission control is still important. | HAO Jiming WANG Litao LI Lin HU Jingnan YU Xuechun | 2005 | Science China Earth Sciences2005，48，z2： | 24 |
| 3 | Impact of hillslope vegetation restoration on gully erosion induced sediment yield显示文摘Facing the eco-environmental construction on the Loess Plateau, especially the vegeta-tion restoration in the semiarid areas, as well as the dam system engineering construction that is about to start, how can the vegetation restoration gain the optimum ecological benefits following the improvement of the preservation rates of trees and grass on the basis of guaranteeing water storage and silt trapping effects? What techniques should be taken to restore vegetation? These questions critical to environmental management on the Loess Plateau have to be settled urgently. According to the different macroscopic spatial distribution patterns of forest and grass on the Loess Plateau, this paper analyzes the macroscopic hillslope and gully management relationship in the middle Yellow River and weight of natural and human factors in erosion-induced sediment yield in the context of environmental background of the major silt producing areas. In light of the current status of the inte-grated management of small watersheds and soil and water conservation measure arrangement schemes of hillslopes and gullies on the Loess Plateau, this paper discusses the impact of vegetation restoration on gully erosion induced sediment yield and the effect of vegetation caused sediment re-duction. Studies indicate that there exists an erosional environmental background related to the natural and human activities in the sediment yield peak values of the sandy and coarse sandy areas in the middle Yellow River, sediment yield modulus is closely related to the synthetic effect of environ-mental elements, and the rainstorms, reclamation rate and forest coverage are the main factors af-fecting sediment yield modulus in the sandy and coarse sandy areas. The key to control soil erosion in the sandy and coarse sandy areas is the conversion of farmland into forestland and grassland, the reduction of reclamation rate and the increase of tree and grass vegetation. Small catchment man-agement should adhere to the principle of simultaneous control of hillslope and gully erosion and combination of biological measures with engineering measures. Engineering measures play an im-portant role in the hillslope vegetation restoration in the initial period. Vegetation restoration can result in a reduction of erosion induced sediment yield in gullies of Yangjiagou by over 75%. | CHEN Hao CAI Qiangguo | 2006 | Science China Earth Sciences2006，49，2： | 13 |
| 4 | Sedimentary environment and development controls of the hydrocarbon source beds: Middle and Upper Proterozoic in northern North China显示文摘Problem on development control of marine source bed hold in Chinese petroleum industry progression. The Hongshuizhuang Formation,Tieling Formation and Xiamaling Forma-tion in the Middle and Upper Proterozoic are important hydrocarbon source beds in northern North China, and investigation of their sedimentary environments and the controls has great significance for petroleum exploration in North China. Based on sedimentology (sequence stratigraphy), palaeoecology, sedimentary geochemistry, and sedimentary palaeogeography, their development pattern is discussed. All these studies indicate that the development controls of the hydrocarbon source beds include a favorite palaeogeographic location, exceeding propa-gation of biomes in low and middle latitudes, anoxic environments, enrichment of phosphorus element and the adsorption of clay minerals during the preservation of organic matter in the ma-rine carbonates. | BAO Zhidong1,2, CHEN Jianfa1, ZHANG Shuichang3, ZHAO Hongwen1, ZHANG Qinghai1 & LI Yan1 1. University of Petroleum, Beijing 102200, China 2. Key Lab of Petroleum Migration and Accumulation Mechanism of Ministry of Education, Beijing 102200, China 3. Petroleum Research Institute of Exploration and Development,Beijing 100083, China | 2004 | Science China Earth Sciences2004，47，z2： | 10 |
| 5 | Experimental investigations on separation control and flow structure around a circular cylinder with synthetic jet显示文摘Circular cylinder separation control and flow structure influenced by the synthetic jet have been experimentally investigated in a water channel. The synthetic jet is- sues from a slot and ejects toward upstream from the front stagnation point of the cylinder. It has been found that, similar to the traditional synthetic jet which is po- sitioned near the separation point or inside the separation region, the present synthetic jet arrangement constitutes an efficient way to control flow separation of the circular cylinder, but with a different control mechanism. The present synthetic jet leads to an upstream displacement of the front stagnation point and the forma- tion of a vortex pair near both sides of the exit orifice. When ReU based on the synthetic jet average exit orifice velocity is about lower than 43, a closed envelope forms in front of the windward side of the cylinder during the blowing cycle of syn- thetic jet, which acts as an apparent modification for the cylinder configuration. When ReU is high enough, an open envelope forms upstream of the cylinder, and the flow around the cylinder becomes much energetic. Thus, regardless of ReU, the present synthetic jet can improve separation for flow around a circular cylinder. With regard to the leeward side, as ReU increases, the flow separation region be- hind the cylinder gradually disappears. The flow over cylinder may be fully attached when the open envelope forms upstream of the cylinder and ReU is greater than 344. Then, the flow past the cylinder will converge near the back stagnation point of the cylinder, where a new vortex pair shedding periodically is generated due to the high shear layer. | WANG JinJun FENG LiHao XU ChaoJun | 2007 | Science China(Technological Sciences)2007，50，5： | 9 |
| 6 | Variable universe stable adaptive fuzzy control of nonlinear system显示文摘A kind of stable adaptive fuzzy control of nonlinear system is implemented using variable universe method. First of all, the basic structure of variable universe adaptive fuzzy controllers is briefly introduced. Then the contraction-expansion factor that is a key tool of variable universe method is defined by means of integral regulation idea, and a kind of adaptive fuzzy controllers is designed by using such a contraction-expansion factor. The simulation on first order nonlinear system is done. Secondly, it is proved that the variable universe adaptive fuzzy control is asymptotically stable by use of Lyapunov theory. The simulation on the second order nonlinear system shows that its simulation effect is also quite good. Finally a useful tool, called symbolic factor, is proposed, which may be of universal significance. It can greatly reduce the settling time and enhance the robustness of the system. | 李洪兴 苗志宏 王加银 | 2002 | Science China(Technological Sciences)2002，45，3： | 9 |
| 7 | A mathematical formulation for optimal control of air pollution显示文摘The problem of optimal control of air pollution using weather forecast results and nu-merical air pollution models is discussed. A mathematical formulation of the problem is presented. The control is an act on pollution sources with feasible constraints. Based on forecasted weather conditions, the objective of the optimal control is to minimize total cost caused by control under the constraint that the pollution concentrations over a certain period and a certain spatial domain are less than some specified values. Using the adjoint method, an effective algorithm is given. Since the optimal solutions are based on weather forecasts, the errors in weather forecasts will cause uncertainties in the optimal solutions. Estimation of impacts of weather forecast errors on the op-timal solutions is discussed using the adjoint sensitivity analysis technique that is an approximated, however very effective method. The adjoint sensitivity analysis technique can be used to calculate the impacts of errors in wind, temperature and initial pollutant concentration fields on performances of the optimal control. | 朱江 曾庆存 | 2003 | Science China Earth Sciences2003，46，10： | 9 |
| 8 | Study of water intakes for oncomelania control based on information of oncomelania behavior and CFD results显示文摘Schistosomiasis is a parasitic disease. They propagate in the Yangtze River valley of Chi-na. The spread of the disease is solely through a middle-agent named oncomelania, so the spread ofschistosomiasis by oncomelania can be controlled by properly designing water intakes which preventoncomelania from entering the farming land or residential areas. In this paper, a successful design pro-cess is reported and a new oncomelania-free intake device is demonstrated in the laboratory. The de-sign of the new intake is based on a sound research program in which an extensive experimental stud-ies have been carried out to gain knowledge of oncomelania eco-hydraulic behaviors and a detailed flowfield information is obtained through CFD simulation. | 李大美 王祥三 赖永根 | 2001 | Science China(Technological Sciences)2001，44，5： | 8 |
| 9 | A novel optimization method of transient stability emergency control based on practical dynamic security region (PDSR) of power systems显示文摘This paper proposes a novel optimization method of transient stability emergency control based on a new concept of the so-called extended practical dynamic security region (EPDSR) defined in this paper and four experiential laws about the EPDSRs found from a number of studies in real power systems. In this method, the effect of a control action is represented by the displacement of EPDSRs critical hyper-plane boundary in the direction of its outer normal vector. If an unstable contingency occurs, appropriate emergency control actions are triggered so that the enlarged EPDSR can cover the current operating point. Based on these ideas, a mathematics model of emergency control strategy is developed for minimizing its total cost and guaranteeing power system transient stability. The simulation results on the 10-generator, 39-bus New-England Test System as well as other real power systems have shown the validity of this method. | YU Yixin LIU Hui ZENG Yuan | 2004 | Science China(Technological Sciences)2004，47，3： | 7 |
| 10 | A preliminary study on vegetation-erosion dynamics and its applications显示文摘Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation. | WANG Zhaoyin 1,2 , WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China 2. International Research and Training Center on Erosion and Sedimentation, Beijing 100084, China | 2005 | Science China Earth Sciences2005，48，5： | 7 |
| 11 | Dynamic extending nonlinear H_∞ control and its application to hydraulic turbine governor显示文摘There exists a large class of nonlinear systems with uncertainties, such as hydrau- lic turbine governors, whose robust control problem is hard to solve by means of the existing robust control approaches. For this class of systems, this work pre- sents a dynamic extending H∞ controller via both differential geometry and H∞ the- ory. Furthermore, based on differential game theory, it has been verified that the proposed control strategy has robustness in the sense that the disturbance can be attenuated effectively because the L2-gain from the disturbance input to the regu- lation output signal could be reduced to any given level. Thirdly, a robust control strategy for hydraulic turbine governor is designed according to the proposed ex- tending H∞ control method, and has been developed into a real control equipment. Finally the field experiments are carried out which show clearly that the developed control equipment can enhance transient stability of power systems more effec- tively than the conventional controller. | MEI ShengWei GUI XiaoYang SHEN Chen LU Qiang | 2007 | Science China(Technological Sciences)2007，50，5： | 6 |
| 12 | Adaptive fuzzy integral sliding mode velocity control for the cutting system of a trench cutter显示文摘This paper presents a velocity controller for the cutting system of a trench cutter(TC). The cutting velocity of a cutting system is affected by the unknown load characteristics of rock and soil. In addition, geological conditions vary with time. Due to the complex load characteristics of rock and soil, the cutting load torque of a cutter is related to the geological conditions and the feeding velocity of the cutter. Moreover, a cutter's dynamic model is subjected to uncertainties with unknown effects on its function. In this study, to deal with the particular characteristics of a cutting system, a novel adaptive fuzzy integral sliding mode control(AFISMC) is designed for controlling cutting velocity. The model combines the robust characteristics of an integral sliding mode controller with the adaptive adjusting characteristics of an adaptive fuzzy controller. The AFISMC cutting velocity controller is synthesized using the backstepping technique. The stability of the whole system including the fuzzy inference system, integral sliding mode controller, and the cutting system is proven using the Lyapunov theory. Experiments have been conducted on a TC test bench with the AFISMC under different operating conditions. The experimental results demonstrate that the proposed AFISMC cutting velocity controller gives a superior and robust velocity tracking performance. | Qi-yan TIAN Jian-hua WEI Jin-hui FANG Kai GUO | 2016 | Frontiers of Information Technology & Electronic Engineering2016，17，1： | 5 |
| 13 | Study on Transformer Magnetic Biasing Control Method for AC Power Supplies显示文摘This paper presents a novel transformer magnetic biasing control method for high-power high-performance AC power supplies. Serious consequences due to magnetic biasing and several methods to overcome magnetic biasing are first discussed. The causes of the transformer magnetic biasing are then analyzed in detail. The proposed method is based on a high-pass filter inserted in the forward path and the feedforward control. Without testing magnetic biasing of transformer, this method can eliminate magnetic biasing of transformer completely in real-time waveform feedback control systems though the zero error of the Hall effect sensors varies with time and temperature. The method has already been employed in a 90KVA AC power supply. It is shown that it offers improved performance over existing ones. In this method, no sensors are used such that the zero error of the Hall effect sensors has not any influence on the system. It is simple to design and implement. Furthermore, the method is suitable for various power applications. | 卢家林 孙晋 苏彦民 | 2001 | Journal of Systems Engineering and Electronics2001，12，4： | 5 |
| 14 | 借助广义判据对多管火箭预估模型实施最优控制(英文)显示文摘利用广义判据 ,给出非线性系统的最优控制解 ,介绍预估多管火箭系统最优控制的一种通用算法 . | 姚俊 | 2000 | 弹道学报2000，12，2： | 5 |
| 15 | Synthesis of mesoporous nano-TiO_(2)doped with Sn by auto-assembly method and photo-catalytic property显示文摘A series of mesoporous nano-TiO2 material doped with Sn are synthesized by a homogenous precipitation method aided by microwave heating, using TiCl4 and SnCl4 as raw materials, urea as precipitator, active carbon as templet, and soluble starch as anti- agglomer-ating reagent. XRD results show that the precursor exists in the amorphous phase, and trans-forms to anatase structure above 400℃. TEM results show that the particle is in spherical shape and the average diameter is 20 nm. EDS results show that the measuring value of compound is in accord with the actual value of the raw materials, and the doping uniformity is good. The photo-catalytic experimental results show that the highest photo-catalytic efficiency can be ob-tained when the content of Sn is 10% (mol pecent), and the decolorization rate of navy blue dye can be as high as 100% after being illuminated by sunlight for 70 min. The photo-catalytic reac-tion is a first-order kinetic reaction. | ZHANG Meihong DING Shiwen WANG Zhenxing ZHANG Yuzhuo | 2005 | Science China Chemistry2005，48，5： | 4 |
| 16 | 基于定量反馈理论的多变量解耦预测控制及其在CSTR化学过程中的应用显示文摘A novel method of incorporating generalized predictive control (GPC) algorithms based on quantitative feedback theory (QFT) principles is proposed for solving the feedback control problem of the highly uncertain and cross-coupling plants. The quantitative feedback theory decouples the multi-input and multi-output (MIMO) plant and is also used to reduce the uncertainties of the system, stabilize the system, and achieve tracking performance of the system to a certain extent. Single-input and single-output (SISO) generalized predictive control is used to achieve performance with higher performance. In GPC, the model is identified on-line, which is based on the QFT input and the plant output signals. The simulation results show that the performance of the system is superior to the performance when only QFT is used for highly uncertain MIMO plants. | 王增会 陈增强 孙青林 袁著祉 | 2006 | Chinese Journal of Chemical Engineering2006，14，6： | 4 |
| 17 | Variable centroid control scheme over hypersonic tactical missile显示文摘This paper presents a brand-new tactical missile control scheme--variable centroid vector control according to the international highlight in the field of missile control and the research status of hypersonic missile control in China. Four critical problems related with the new control method are included: improving phase control in the spinning missile single-channel control; establishing variable centroid controlled spinning missile attitude dynamics equations; analyzing variable centroid control strategies and analyzing the stability of the controlled missile and implementing robust control. The achievements and results obtained are valuable and helpful to the theoretical explorations and engineering applications. | Yl Yan(易彦) ZHOU Fengqi(周凤岐) | 2003 | Science China(Physics,Mechanics & Astronomy)2003，46，6： | 3 |
| 18 | Synergy methodology for multi-objective operational control of reservoirs in Yellow River basin显示文摘This paper presents an application of synergy methodology to a multi- objective operational control of reservoirs. This methodology enables a comprehensive consideration of multi-objectives which may be conflicting and non commensurate such as municipal and industrial water supply, flood protection, and hydroelectric power generation etc. On the basis of the synergy theory, a harmony degree model of sub- system was established to describe the coordination magnitude. Combined with information entropy, a harmony degree entropy was proposed to determine the water resources evolvement direction. While implementing the control, an initial scheme for reservoir operation was obtained from simulation first, then control was carried out according to the harmony degree and harmony degree entropy by applying synergy theory. The application of the methodology to reservoir system in the Yellow River was reported in this paper through a case study. | HUANG Qiang CHANG Jianxia WANG Yimin PENG Shaoming | 2004 | Science China(Technological Sciences)2004，47，z1： | 3 |
| 19 | Design of a robust guidance law via active disturbance rejection control显示文摘Focusing on the three-dimensional guidance problem in case of target maneuvers and response delay of the autopilot, the missile guidance law utilizing active disturbance rejection control(ADRC) is proposed. Based on the nonlinear three-dimensional missile target engagement kinematics, the guidance model is established. The target acceleration is treated as a disturbance and the dynamics of the autopilot is considered by using a first-order model. A nonlinear continuous robust guidance law is designed by using a cascaded structure ADRC controller. In this method the disturbance is estimated by using the extended state observer(ESO) and compensated during each sampling period. Simulation results show that the proposed cascaded loop structure is a viable solution to the guidance law design and has strong robustness with respect to target maneuvers and response delay of the autopilot. | Yanbo Yuan Ke Zhang | 2015 | Journal of Systems Engineering and Electronics2015，26，2： | 2 |
| 20 | Flocculation control study based on fractal theory显示文摘A study on flocculation control based on fractal theory was carried out. Optimization test of chemical coagulant dosage confirmed that the fractal dimension could reflect the flocculation degree and settling characteristics of aggregates and the good correlation with the turbidity of settled effluent. So that the fractal dimension can be used as the major parameter for floc-culation system control and achieve self-acting adjustment of chemical coagulant dosage. The fractal dimension flocculation control system was used for further study carried out on the effects of various flocculation parameters, among which are the dependency relationship among aggregates fractal dimension, chemical coagulant dosage, and turbidity of settled effluent under the conditions of variable water quality and quantity. And basic experimental data were obtained for establishing the chemical coagulant dosage control model mainly based on aggregates fractal dimension. | 常颖 刘前军 张金松 | 2005 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2005，6，10： | 2 |
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