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Improvements of marine clay slurries using chemicale-physical combined method(CPCM) 被引量:1
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作者 Dongqing Wu Wenyu Xu Romy Tjuar 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期220-225,共6页
In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization ... In this paper, the effectiveness, applicability and validity of chemicalephysical combined methods(CPCMs) for treatment of marine clay (MC) slurries were evaluated. The method CPCM1 combineschemical stabilization and vacuum preloading (VP), while CPCM2 is similar to CPCM1 but includes boththe application of surcharge and use of geo-bags to provide confinement during surcharge preloading.The key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on thechemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling anddyke conditions, respectively. The test results show that the shear strength (cu) of treated slurry byCPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reducethe treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows fasterconsolidation and higher preloading that help to achieve higher mechanical properties of the stabilizedslurry. There are consistent relationships between cU and water content of slurries treated by CPCM2.Several important observations were also made based on comparisons of experimental data. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 Chemical e physical combined method(CPCM) Soil improvement Marine clay(MC) slurry Land reclamation Chemical stabilization Vacuum preloading(VP) Geo-bags SURCHARGE
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Physical Parameter Identification Method Based on Modal Analysis for Two-axis On-road Vehicles:Theory and Simulation 被引量:3
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作者 ZHENG Minyi ZHANG Bangji +1 位作者 ZHANG Jie ZHANG Nong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期756-764,共9页
Physical parameters are very important for vehicle dynamic modeling and analysis.However,most of physical parameter identification methods are assuming some physical parameters of vehicle are known,and the other unkno... Physical parameters are very important for vehicle dynamic modeling and analysis.However,most of physical parameter identification methods are assuming some physical parameters of vehicle are known,and the other unknown parameters can be identified.In order to identify physical parameters of vehicle in the case that all physical parameters are unknown,a methodology based on the State Variable Method(SVM) for physical parameter identification of two-axis on-road vehicle is presented.The modal parameters of the vehicle are identified by the SVM,furthermore,the physical parameters of the vehicle are estimated by least squares method.In numerical simulations,physical parameters of Ford Granada are chosen as parameters of vehicle model,and half-sine bump function is chosen to simulate tire stimulated by impulse excitation.The first numerical simulation shows that the present method can identify all of the physical parameters and the largest absolute value of percentage error of the identified physical parameter is 0.205%;and the effect of the errors of additional mass,structural parameter and measurement noise are discussed in the following simulations,the results shows that when signal contains 30 d B noise,the largest absolute value of percentage error of the identification is 3.78%.These simulations verify that the presented method is effective and accurate for physical parameter identification of two-axis on-road vehicles.The proposed methodology can identify all physical parameters of 7-DOF vehicle model by using free-decay responses of vehicle without need to assume some physical parameters are known. 展开更多
关键词 Parameter identification free-decay response state variable method modal parameter physical parameter
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Effects of Varieties and Cooking Methods on Physical and Chemical Characteristics of Cooked Rice 被引量:1
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作者 Merynda Indriyani SYAFUTRI Filli PRATAMA +1 位作者 Friska SYAIFUL Achmad FAIZAL 《Rice science》 SCIE CSCD 2016年第5期282-286,共5页
To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each c... To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each combination of the factors was repeated three times. The first factor was rice variety(Ciherang and Ciliwung) and the second factor was the cooking method(stovetop, boiling and steaming, and rice cooker). Results showed that Ciherang and Ciliwung varieties were classified into slender grain rice type with yellowred color. The amylose content of Ciherang was classified as moderate, while the amylose content of Ciliwung classified as low. The most abundant amino acid contained in Ciherang and Ciliwung varieties was glutamic acid. Statistical analysis showed that cooking method had significant effects on texture, lightness, chroma, hue and moisture content of cooked rice. Rice cooked with liwet method had the lowest texture value, lowest lightness value, highest chroma value, and highest moisture content. 展开更多
关键词 physical and chemical characteristic cooking method rice variety amino acid
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MEASUREMENT METHOD AND PHYSICAL MODEL OF VSC CONDUCTIVITY AND ITS APPLICATIONS IN CONDUCTING POLYMERS
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作者 万梅香 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第4期330-339,共10页
Method of VSC (Voltage Shorted Compaction)can be used to determine the intrinsic temperature dependence ofconductivity ofpolycrystalline compaction. The experimental conditions and technical key for preparation of VSC... Method of VSC (Voltage Shorted Compaction)can be used to determine the intrinsic temperature dependence ofconductivity ofpolycrystalline compaction. The experimental conditions and technical key for preparation of VSC device and its physical model as well as its applications in conducting polymers are discussed in detail. 展开更多
关键词 VSC show MEASUREMENT method AND physical MODEL OF VSC CONDUCTIVITY AND ITS APPLICATIONS IN CONDUCTING POLYMERS
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Growth and Physical Properties of CdS/TiO_2 Bilayer by Plasma-Based Method
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作者 T.Hoseinzadeh M.Ghoranneviss +1 位作者 E.Akbarnejad Z.Ghorannevis 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第3期39-42,共4页
The titanium oxide (TiO2) nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide (CdS) nanoparticles arc grown on top opened TiO2... The titanium oxide (TiO2) nanotubes have attracted attention for their use in dye-sensitized solar cells as photoanode. In this study semiconducting cadmium sulfide (CdS) nanoparticles arc grown on top opened TiO2 nanotubes arrays by radio-frequency magnetron sputtering. X-ray diffraction, scanning electron mieroscopy, transmission electron microscopy and diffuse reflection spectra are used to study structural, morphological and optical properties of the CdS/TiO2 bilayer. 展开更多
关键词 CDS TIO Growth and physical Properties of CdS/TiO2 Bilayer by Plasma-Based method
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Studies of Atomic Structure and Physical Properties of Metal Clusters in MgO by HREM and Nano-probe Methods
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作者 Nobuo Tanaka (Dept. of Applied Physics, School of Engineering, Nagoya University, Nagoya, 464-01, Japan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期265-270,共6页
Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area el... Nanometer-sized metal clusters were prepared inside single crystalline MgO films by vacuum co-deposition of metals and MgO. The atomic structure was studied by high-resolution electron microscopy (HREM) and nm-area electron diffraction. The size of the clusters is ranging from 1 nm to 3 nm without those larger than 5 nm, and most of them have definite epitaxial orientations with the MgO matrix films. The character of the composite films is very much useful for the studies of various kinds of physical properties with anisotroPy. The physical properties such as electric transport, magnetic, optical absorption, sintering and catalytic ones were thus measured on the same samples analyzed by HREM by using high sensitivity apparatus with interest of clarifying the retationship between the atomic structure and physical properties 展开更多
关键词 FIGURE NANO Studies of Atomic Structure and physical Properties of Metal Clusters in MgO by HREM and Nano-probe methods HREM MGO
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Physical Macrohardness of the Kinetic Indentation of the Material: Function and Universal Unit of Measure (Part 1)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期64-78,共15页
Three directions of development of kinetic indentation methods.Physical-energetic analysis of the indentation force diagram according to ISO 14577.Physical theory and universal criterion for the macrohardness of a mat... Three directions of development of kinetic indentation methods.Physical-energetic analysis of the indentation force diagram according to ISO 14577.Physical theory and universal criterion for the macrohardness of a material.Model of the physical process,thermomechanical potential,function of the state of the kinetic macroindentation process.Method for determining the physical function and unit of measurement of the kinetic macrohardness of a material.The ratio of the values of the empirical(standard)and physical macrohardness of the material.Physical reason for the appearance of the size effect in empirical indentation methods.The principle of determining the standard value of physical macrohardness. 展开更多
关键词 Review physical theory of kinetic indentation method for determining physical macrohardness of the material
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Physical Properties of the Function and Number of Empirical Macrohardness of the Material: Universal Physical Unit of Measurement of Macro Hardness (Part 2)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期79-91,共13页
Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical com... Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical comparison method and a criterion for the similarity of the physical and empirical macrohardness of a material are proposed.The physical properties of the hardness measurement process using the Calvert-Johnson method are shown.The physical reasons for the size effect when measuring macrohardness are considered.The universal physical unit and standard of macrohardness of kinetic macroindentation by a sphere is substantiated. 展开更多
关键词 physical theory of kinetic indentation method for determining the function and number of physical macrohardness ratio of empirical and physical macrohardness of a material universal physical unit of macrohardness.
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A review of welding residual stress test methods 被引量:7
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作者 甘世明 刘华荥 +1 位作者 翟之平 韩永全 《China Welding》 CAS 2022年第2期45-55,共11页
Due to local uneven heating during the welding process,the residual stress of the structure after welding affects the reliability of it.In order to ensure the reliability,it is of great significance to test the residu... Due to local uneven heating during the welding process,the residual stress of the structure after welding affects the reliability of it.In order to ensure the reliability,it is of great significance to test the residual stress distribution of the welded joint.It has always been the focus to find a simple and feasible method for residual stress testing to quickly and accurately obtain the residual stress distribution of welded joints.The mechanical measurement method has high measurement accuracy,convenient and easy operation,but it will cause certain damage to the components.Physical measurement method can avoid damage to components,but its test cost is usually high,and its measurement accuracy can also be affected by the material microstructure characteristics of welded components.Based on the advantages and disadvantages of these two residual stress test methods,a modal test method is proposed.This method is a non-destructive measurement method.Based on the mathematical relationship between the residual stress of the welded structure and the natural frequency(mathematical model),the natural frequency is measured through the modal test to calculate the residual stress quickly.However,it is difficult to establish a mathematical model with this method,and it is not suitable for realization. 展开更多
关键词 welding residual stress mechanical measurement method physical measurement method modal test method
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PHYSICAL VALUE MAPPING ALGORITHM OF MESH IN FINE CAE ANALYSIS OF AUTOMOBILE BODY STRUCTURE 被引量:2
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作者 Hu Ping Gong Kejia Bao Yidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期338-341,共4页
A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from... A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product. 展开更多
关键词 Fine CAE analysis of auto body structure Finite element mesh Arc method physical value mapping
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SiC大单晶的生长
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作者 徐良瑛 束碧云 《人工晶体学报》 EI CAS CSCD 北大核心 2000年第S1期143-,共1页
Silicon carbide (SiC) single crystal,which hasn’t melting point at normal pressu r e and sublimates at temperature above 2000℃,is a wide bandgap semiconductor.Si lic on carbide has more than 200 kinds of polytype.Am... Silicon carbide (SiC) single crystal,which hasn’t melting point at normal pressu r e and sublimates at temperature above 2000℃,is a wide bandgap semiconductor.Si lic on carbide has more than 200 kinds of polytype.Among these polytypes,3C SiC、6H SiC and 4H SiC are the most common ones,the band width of them are 2.4eV,3.0eV , an d 3.4eV,restpectively.For its high temperature tolerance and radiation resistanc e,silicon carbide semiconductor can be extensively used to fabricate the power d evi ces and electroluminescence devices operating at high power,high frequency and high radiation environments. The aim of this paper is to introduce our research results of the growth of larg e SiC single crystals by physical vapor transport method.The seed is SiC single crystal wafer with perfect (0001)Si face,which is chosen from the furnace growi ng the green abrasive material of SiC in industry.The source is green powder of SiC .The seed and the source are placed into the graphite crucible of a graphite res i stively heated vacuum furnace.The growth chamber is filled with the atmosphere o f pure araon.When the temperature of source rises to 2300℃,the crystal growth p ro ceeds.The rate of crystal growth is dependent on the growth temperature,the pres sure in furnace and the temperature gradient and distance between the seed and t h e source.Under the controlled growth conditions,the bulk SiC crystal with a diam eter of 40mm and a thickness of 15mm is obtained.The crystal appears to be n type electrical conductivity,the results of X ray Laue photography analysis indicat e that it is 6H SiC polytype.The defects of the crystal are also studied by many kinds of method. 展开更多
关键词 SiC crystal semiconductor material physical vapor transport method
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Classification and Summarization of Solar Irradiance and Power Forecasting Methods:A Thorough Review 被引量:1
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作者 Bo Yang Tianjiao Zhu +8 位作者 Pulin Cao Zhengxun Guo Chunyuan Zeng Danyang Li Yijun Chen Haoyin Ye Ruining Shao Hongchun Shu Tao Yu 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第3期978-995,共18页
Solar forecasting is of great importance for ensuring safe and stable operations of the power system with increased solar power integration,thus numerous models have been presented and reviewed to predict solar irradi... Solar forecasting is of great importance for ensuring safe and stable operations of the power system with increased solar power integration,thus numerous models have been presented and reviewed to predict solar irradiance and power forecasting in the past decade.Nevertheless,few studies take into account the temporal and spatial resolutions along with specific characteristics of the models.Therefore,this paper aims to demonstrate a comprehensive and systematic review to further solve these problems.First,five classifications and seven pre-processing methods of solar forecasting data are systematically reviewed,which are significant in improving forecasting accuracy.Then,various methods utilized in solar irradiance and power forecasting are thoroughly summarized and discussed,in which 128 algorithms are elaborated in tables in the light of input variables,temporal resolution,spatial resolution,forecast variables,metrics,and characteristics for a more fair and comprehensive comparison.Moreover,they are categorized into four groups,namely,statistical,physical,hybrid,and others with relevant application conditions and features.Meanwhile,six categories,along with 30 evaluation criteria,are summarized to clarify the major purposes/applicability of the different methods.The prominent merit of this study is that a total of seven perspectives and trends for further research in solar forecasting are identified,which aim to help readers more effectively utilize these approaches for future in-depth research. 展开更多
关键词 Hybrid methods physical methods preprocessing methods solar irradiance and power forecasting statistical methods
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Conceptual design and RCS performance research of shipborne early warning aircraft 被引量:6
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作者 Kuizhi Yue Yong Gao +1 位作者 Guanxiong Li Dazhao Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期968-976,共9页
In order to improve the survivability of the aircraft,conceptual design and radar cross section(RCS) performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early wa... In order to improve the survivability of the aircraft,conceptual design and radar cross section(RCS) performance research are done. The CATIA software is used to design the 3D digital model of the shipborne early warning aircraft, and some measures are taken to reduce the RCS characteristics of the early warning aircraft at the same time. Based on the physical optics method and the equivalent electromagnetic flow method,the aircraft's RCS characteristics and strength distribution characteristics are simulated numerically, and compared with the foreign advanced shipborne early warning aircraft. The simulation results show that under the X radar band, when the incident wave pitching angle is 0?, compared with the foreign advanced shipborne early warning aircraft, the forward RCS average value of the conceptual shipborne early warning aircraft is reduced to 24.49%, the lateral RCS average value is reduced to 5.04%, and the backward RCS average value is reduced to 39.26%. The research results of this paper are expected to provide theoretical basis and technical support for the conceptual design and the stealth design of the shipborne early warning aircraft. 展开更多
关键词 conceptual design STEALTH shipborne early warning aircraft physical optics method SIMULATION
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Performance and uncertainty analysis of a short-term climate reconstruction based on multi-source data in the Tianshan Mountains region,China 被引量:2
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作者 LI Xuemei Slobodan P SIMONOVIC +2 位作者 LI Lanhai ZHANG Xueting QIN Qirui 《Journal of Arid Land》 SCIE CSCD 2020年第3期374-396,共23页
Short-term climate reconstruction,i.e.,the reproduction of short-term(several decades)historical climatic time series based on the relationship between observed data and available longer-term reference data in a certa... Short-term climate reconstruction,i.e.,the reproduction of short-term(several decades)historical climatic time series based on the relationship between observed data and available longer-term reference data in a certain area,can extend the length of climatic time series and offset the shortage of observations.This can be used to assess regional climate change over a much longer time scale.Based on monthly grid climate data from a Coupled Model Inter-comparison Project phase 5(CMIP5)dataset for the period of 1850–2000,the Climatic Research Unit(CRU)dataset for the period of 1901–2000 and the observed data from 53 meteorological stations located in the Tianshan Mountains region(TMR)of China during the period of 1961–2011,we calibrated and validated monthly average temperature(MAT)and monthly accumulated precipitation(MAP)in the TMR using the delta,physical scaling(SP)and artificial neural network(ANN)methods.Performance and uncertainty during the calibration(1971–1999)and verification(1961–1970)periods were assessed and compared using traditional performance indices and a revised set pair analysis(RSPA)method.The calibration and verification processes were subjected to various sources of uncertainty due to the influence of different reconstructed variables,different data sources,and/or different methods used.According to traditional performance indices,both the CRU and CMIP5 datasets resulted in satisfactory calibrated and verified MAT time series at 53 meteorological stations and MAP time series at 20 meteorological stations using the delta and SP methods for the period of 1961–1999.However,the results differed from those obtained by the RSPA method.This showed that the CRU dataset produced a low degree of uncertainty(positive connection degree)during the calibration and verification of MAT using the delta and SP methods compared to the CMIP5 dataset.Overall,the calibrated and verified MAP had a high degree of uncertainty(negative connection degree)regardless of the dataset or reconstruction method used.Therefore,the reconstructed time series of MAT for the period of 1850(or 1901)–1960 based on the CRU and CMIP5 datasets using the delta and SP methods could be used for further study.The results of this study will be useful for short-term(several decades)regional climate reconstruction and longer-term(100 a or more)assessments of regional climate change. 展开更多
关键词 climate reconstruction climate change delta method physical scaling method artificial neural network(ANN) CRU dataset CMIP5 dataset
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体育教育专业运用导式教学法的实践与研究 被引量:3
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作者 朱杰 《西安体育学院学报》 2000年第1期76-77,共2页
本文根据现代教学的发展趋势 ,结合高校体育教育专业的实际情况 ,通过笔者近几年在乒乓球普修课实践中的探索、研究 ,揭示了学导式教学法在体育教学中的价值 ,论述了教学法的内涵和教法程序 。
关键词 体育教育专业 学导式教学法 程序 高校 乒乓球
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A general multi-objective programming model for minimum ecological flow or water level of inland water bodies 被引量:1
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作者 Song Hao SHANG 《Journal of Arid Land》 SCIE CSCD 2015年第2期166-176,共11页
Assessment of ecological flow or water level for water bodies is important for the protection of de- graded or degrading ecosystems caused by water shortage in arid regions, and it has become a key issue in water reso... Assessment of ecological flow or water level for water bodies is important for the protection of de- graded or degrading ecosystems caused by water shortage in arid regions, and it has become a key issue in water resources planning. In the past several decades, many methods have been proposed to assess ecological flow for rivers and ecological water level for lakes or wetlands. To balance water uses by human and ecosystems, we proposed a general multi-objective programming model to determine minimum ecological flow or water level for inland water bodies, where two objectives are water index for human and habitat index for ecosystems, respectively Using the weighted sum method for multi-objective optimization, minimum ecological flow or water level can be determined from the breakpoint in the water index-habitat index curve, which is similar to the slope method to de- termine minimum ecological flow from wetted perimeter-discharge curve. However, the general multi-objective programming model is superior to the slope method in its physical meaning and calculation method. This model provides a general analysis method for ecological water uses of different inland water bodies, and can be used to define minimum ecological flow or water level by choosing appropriate water and habitat indices. Several com- monly used flow or water level assessment methods were found to be special cases of the general model, including the wetted perimeter method and the multi-objective physical habitat simulation method for ecological river flow, the inundated forest width method for regeneration flow of floodplain forest and the lake surface area method for eco- logical lake level. These methods were applied to determine minimum ecological flow or water level for two repre- sentative rivers and a lake in northern Xinjiang of China, including minimum ecological flow for the Ertix River, minimum regeneration flow for floodplain forest along the midstream of Kaxgar River, and minimum ecological lake level for the Ebinur Lake. The results illustrated the versatility of the general model, and can provide references for water resources planning and ecosystem protection for these rivers and lake. 展开更多
关键词 minimum ecological flow minimum ecological water level wetted perimeter method physical habitat simulation method inundated forest width method lake surface area method
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RCS Reduction of Airborne Dispenser
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作者 郝璐 吴甲生 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期58-62,共5页
The radar cross section (RCS) of dispenser and its components is computed by graphical electromagnetic computing (GRECO) method, which bases on physical optics (PO) method. A satisfied agreement is gotten between comp... The radar cross section (RCS) of dispenser and its components is computed by graphical electromagnetic computing (GRECO) method, which bases on physical optics (PO) method. A satisfied agreement is gotten between computed and measured results outdoor. The results show that the main scattering source of the dispenser is the mirror reflecting of the body; in the most crucial nose-on region, the nose mirror reflecting plays important role; the corner reflecting is important to the fins' RCS. The corresponding measures to reduce dispenser's RCS are proposed. It is indicated that to reduce RCS, shaping should be adopts first, while aerodynamic characteristics and stealth characteristics should be considered synthetically during the design of dispenser. 展开更多
关键词 DISPENSER radar cross section (RCS) physical optics method (PO) outdoor RCS test graphical electromagnetic computing (GRECO)
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Comparison of Liquid Water Content Retrievals for Airborne Millimeter-Wave Radar with Different Particle Parameter Schemes
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作者 崔新东 姚志刚 +3 位作者 赵增亮 王敏威 范春晖 苏涛 《Journal of Tropical Meteorology》 SCIE 2020年第2期188-198,共11页
In the application of the physical iterative method to retrieve millimeter-wave radar liquid water content(LWC)and liquid water path(LWP),particle parameter scheme is the main factor affecting retrieval performance.In... In the application of the physical iterative method to retrieve millimeter-wave radar liquid water content(LWC)and liquid water path(LWP),particle parameter scheme is the main factor affecting retrieval performance.In this paper,synchronous measurements of an airborne millimeter-wave radar and a hot-wire probe in stratus cloud are used to compare the LWC retrievals of the oceanic and continental particle parameter scheme with diameter less than 50μm and the particle parameter scheme with diameter less than 500μm and 1500μm(scheme 1,scheme 2,scheme 3,and scheme4,respectively).The results show that the particle parameter scheme needs to be selected according to the reflectivity factor when using the physical iterative method to retrieve the LWC and LWP.When the reflectivity factor is less than-30 d BZ,the retrieval error of scheme 1 is the minimum.When the reflectivity factor is greater than-30 d BZ,the retrieval error of scheme 4 is the minimum.Based on the reflectance factor value,the LWP retrievals of scheme 4 are closer to the measurements,the average relative bias is 5.2%,and the minimum relative bias is 4.4%.Compared with other schemes,scheme 4 seems to be more useful for the LWC and LWP retrieval of stratus cloud in China. 展开更多
关键词 millimeter-wave radar physical iterative method particle parameter scheme liquid water content liquid water path
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Radiation Characteristics of the Reflector Antenna with Random Perforated Holes
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作者 董涛 徐晓文 肖疆 《Journal of Beijing Institute of Technology》 EI CAS 2004年第4期378-380,共3页
The radiation characteristics of a doubly curved shaped reflector antenna with random holes is analyzed by physical optics (PO) method, and the probability model of the random holes and its numerical realization metho... The radiation characteristics of a doubly curved shaped reflector antenna with random holes is analyzed by physical optics (PO) method, and the probability model of the random holes and its numerical realization method are presented. The radiation patterns show that in the azimuth plane the peak sidelobe level becomes much higher as the reflector surface with random holes. The simulation results can provide a theoretical guidance for the radar attackers. 展开更多
关键词 reflector antenna physical optics(PO) method radiation characteristics random perforated holes
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On the PoincaréAlgebra in a Complex Space-Time Manifold
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作者 Nathalie Debergh Gilles D’Agostini Jean-Pierre Petit 《Journal of Modern Physics》 2021年第3期218-228,共11页
We extend the Poincaré group to the complex Minkowski space-time. Special attention is paid to the corresponding algebra that we achieve through matrices as well as differential operators. We also point out the g... We extend the Poincaré group to the complex Minkowski space-time. Special attention is paid to the corresponding algebra that we achieve through matrices as well as differential operators. We also point out the generalizations of the two Casimir operators. 展开更多
关键词 Complex Minkowski Manifold Poincaré Group Lie Algebraic methods Applied to Physics
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