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Fuzzy tracking control design for hypersonic vehicles via T-S model

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Science china(Information Sciences) 2011年第3期54卷 521-528页

作者： GAO DaoXiang 1 & SUN ZengQi 2 1 School of technology, beijing Forestry university, beijing 100083, china 2 State Key Laboratory of Intelligent technology and System, Department of Computer Science and technology, Tsinghua university, beijing 100084, china School of technology Beijing Forestry University Beijing China State Key Laboratory of Intelligent technology and System Department of Computer Science and Technology Tsinghua University Beijing China

The main focus of this paper is on designing a T-S fuzzy controller for the hypersonic vehicle. The longitudinal dynamics of the vehicle are studied using time-scale decomposition to reduce the complexity of T-S modeling. The dynamic inversion with PI control technique is applied for the slow dynamics to derive the flight path angle command and throttle setting by taking the pilot altitude and velocity command as its inputs. The T-S fuzzy controller is designed for the fast dynamics to derive the elevator deflection to track the flight path angle command. The discrepancy between the T-S model and real vehicle model is considered by using sliding mode control for the system stability. Simulation results are included to show the effectiveness of the controller.

关键词： fuzzy control T-S model sliding mode control hypersonic vehicle

Late Oligocene Sedimentary Hiatus in Deep Sea Area of South china Sea, Result of Calcareous Nannofossils from ODP Site 1148

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Journal of china university of Geosciences 2004年第1期15卷 69-74页

作者： Su Xin Key Laboratory of Lithospheric and Lithoprobing technology, china university of Geosciences, Ministry of Education, beijing 100083, china State pilot Laboratory of Coast & Island Development, Nanjing university, Nanjing 210093, china Key Laboratory of Lithospheric and Lithoprobing technology China University of Geosciences Ministry of Education Beijing 100083 China State pilot Laboratory of Coast & Island Development Nanjing University Nanjing 210093 China

In order to determine the age of the sedimentary hiatus and its geological significance, a study of the calcareous nannofossil biostratigraphy was carried out. Detailed stratigraphical data of the Late Oligocene-Early Miocene diagnostic species thus obtained. The nannofossil zonation of this interval was subdivided and the Oligocene-Miocene boundary was further determined. Several last Late Oligocene events were recognized, indicating a long-term sedimentary hiatus in the uppermost Upper Oligocene. The time span of the hiatus was estimated for about 2.2 Ma, at least from 23.9 to 26.1 Ma. The lithological and geophysical data from Site 1148 indicate some abrupt sedimentary changes that occurred below and above the hiatus. This hiatus at Site 1148 was probably related to the tectonic change, a major ridge jump during the seafloor spreading in the Late Oligocene South china Sea.

关键词： sedimentary hiatus calcareous nannofossils Late Oligocene ODP Site 1148 South china Sea.

Improving Removal Efficiency of Organic Matters by Adding Phosphorus in Drinking Water Biofiltration Treatment

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Biomedical and Environmental Sciences 2003年第1期16卷 29-39页

作者： XIN YU, XIAO-JIAN ZHANG, AND ZHAN-SHENG WANGDepartment of Environmental Science and Engineering, Tsinghua university, beijing 100084, china Department of Environmental Science and Engineering Tsinghua University 北京 100084

Objective To investigate phosphorus limitation and its effect on the removal efficiency of organic matters in drinking water biological treatment. Methods Bacterial growth potential (BGP) method and a pair of parallel pilot-scale biofilters were used for the two objectives, respectively. Results The addition of phosphorus could substantially increase the BGPs of the water samples and the effect was stronger than that of the addition of carbon. When nothing was added into the influents, both CODMn removals of the parallel biofilters (BF1 and BF2) were about 15%. When phosphate was added into its influent, BF1 performed a CODMn removal, 6.02 percentage points higher than the control filter (BF2) and its effluent had a higher biological stability. When the addition dose was 20μg. L-1, no phosphorus pollution would occur and there was a good linear relationship between the microbial utilization of phosphorus and the removal efficiency of organic matters. Conclusions Phosphorus was a limiting nutrient and its limitation was stronger than that of carbon. The addition of phosphate was a practical way to improve the removal efficiency of organic matters in drinking water biological treatment.

关键词： Drinking water Biofiltration Phosphorus Limiting nutrient Organic matters Biological stability

Multi-origin alkanes related to CO_2-rich, mantle-derived fluid in Dongying Sag, Bohai Bay Basin

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Chinese Science Bulletin 2002年第20期47卷 1756-1760页

作者： JIN Zhijun, ZHANG Liuping, ZENG Jianhui & YANG LeiBasin & Reservoir Research Center, university of Petroleum, beijing 102249, china Key Laboratory for Hydrocarbon Accumulation Mechanism of Chinese Ministry of Education, university of Petroleum, beijing 1 Basin and Reservoir Research Center University of Petroleum Beijing 102249 China Key Lab. Hydrocarbon Accumul. Mech. University of Petroleum Beijing 102249 China

With the newly obtained carbon isotope data for the natural gas, a pilot study of multiple-sourced alkanes related to the mantled-derived fluid is presented. The carbon isotope values of alkanes in the Dongying Sag possess the features indicating a general organic origin. However, there are two sub-populations in the isotopic data set, which reflect two specific types of origins. In general, the sub-population with high δ13CCH4 values is related to the CO2-rich, mantle-derived fluid, and it is distributed in the belts where mantle-derived fluid flow and basic volcanic activities have occurred. Geological and geochemical studies demonstrate that this variation of methane carbon isotope values in the Dongying Sag is unrelated with the basin bury and thermal histories, types of source rocks, and reactions between basin fluid and rocks. Mixing of mantle-derived fluid and organic sourced hydrocarbons is probably the cause for the variation.

关键词： mantle-derived fluid organic origin hydrocarbons in-teraction carbon isotope.

Origin of a native sulfur chimney in the Kueishantao hydrothermal field, offshore northeast Taiwan

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Science china Earth Sciences 2007年第11期50卷 1746-1753页

作者： ZENG ZhiGang1, LIU ChangHua1,2, CHEN ChenTung A3, YIN XueBo1, CHEN DaiGeng1,2, WANG XiaoYuan1,2, WANG XiaoMei1,2 & ZHANG GuoLiang1,2 1 Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, china 2 Graduate university of Chinese Academy of Sciences, beijing 100049, china 3 Institute of Marine Geology and Chemistry, National Sun Yat-Sen university, Kaohsiung 804, Taiwan, china Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate university of Chinese Academy of Sciences Beijing China Institute of Marine Geology and Chemistry National Sun Yat-Sen University Kaohsiung China

Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Labo-ratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREE21×10?9), and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite, implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration. The sulfur isotopic compo-sitions of the native sulfur samples reveal that the sulfur of the chimney, from H2S and SO2, originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao ande-site and partly from seawater. Combining these results with an analysis of the thermodynamics, it is clear that from the relatively low temperature (<116 ℃ ), the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.

关键词： origin,native sulfur chimney,Kueishantao hydrothermal field,northeast Taiwan

A SIMULATION STUDY ON TAKE-OFF AND LANDING DYNAMICS OF FLY-BY-WIRE CONTROL SYSTEM AIRCRAFT

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Chinese Journal of Aeronautics 1993年第1期 70-78页

作者： Feng Ya-chang,Chen Gang,Li Pei-qiong (beijing university of Aeronautics and Astronautics,beijing,china,100083)

Based on the dynamic theory of rigid body systems and flying characteristics of aircraftduring take-off and landing, a six degree of freedom aircraft equation of landinggears-aircraft fuselage rigid bodies system is formulated. The time domain step-targettracking pilot model is valuable to the analysis of flying qualities of pilot vehicle systemduring take-off and landing. The mathematical, models of mechanical control system andfly-by-wire control system are provided. The nonlinear time domain computer programprovides a complete quantitative analysis of aircraft take-off and landing dynamics, andthe numerical simulation results agree well with the real flight test data.

关键词： A SIMULATION STUDY ON TAKE-OFF AND LANDING DYNAMICS OF FLY-BY-WIRE CONTROL SYSTEM AIRCRAFT body test Chen

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science china Earth Sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3 1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china 2 Graduate School of Chinese Academy of Sciences,beijing 100049,china 3 Department of Science and technology,Bryant university,Smithfield RI 02917,USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China Department of Science and technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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Science china Technological Sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1,2,3, WAN WeiXing1, LIU LiBo1, NING BaiQi1, ZHAO BiQiang1 & ZHANG ManLian1 1 Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2 Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, china 3 Graduate university, Chinese Academy of Sciences, beijing 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Chinese Academy of Sciences Graduate University Beijing China

The TIME-IGGCAS (Theoretical Ionospheric Model of the Earth in Institute of Ge- ology and Geophysics, Chinese Academy of Sciences) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IRI, NeQuick-ITUR, and TItheridge temperature models) and multi-observations (GPS, Ionosondes, Topex, DMSP, FORMOSAT, and CHAMP) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

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Chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： Ying-nan Xuan Yan Gao Yong Huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences, Guangzhou 510650 china Institute of Chemistry Chinese Academy of Sciences, beijing 100080 china Department of Polymer Science, college of Chemical Engineering Dalian university of technology, Dalian 116012, china 中科院广州化学所 Laboratory of Cellulose and Lignocellulosics Chemistry CAS Guangzhou 510650 Department of Polymer Science College of Chemical Engineering Dalian University of Technology Dalian 116012

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group