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Discussion on Calculation Method of Poverty Incidence in the Exit Evaluation of Poverty-Stricken Counties and Villages 被引量:4
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作者 杨子生 《Agricultural Science & Technology》 CAS 2017年第9期1766-1769,共4页
Poverty incidence is the key index that needs to be measured in the poverty exit examination and evaluation of 832 poverty-stricken counties and 128 000 poverty-stricken villages. In this paper, based on the statement... Poverty incidence is the key index that needs to be measured in the poverty exit examination and evaluation of 832 poverty-stricken counties and 128 000 poverty-stricken villages. In this paper, based on the statement of general concept and conventional calculation method of the poverty incidence, the calculation method of poverty incidence in the exit evaluation of poverty-stricken counties (also including poverty-stricken township and poverty-stricken villages) was investigated through the view of the third-party evaluation. In addition to considering the previous "number of planned poverty remaining population", the method also needed to give consideration to the exiting mistaken population, evaluation missing population. Based on the case in Yuanyang County, Honghe Hani and Yi Autonomous Prefecture, Yunnan Province, the poverty incidences of 10 exit planning villages by the end of 2017 in Yuanyang County were investigated and estimated, and suggestions were proposed to promote the precise poverty alleviation and poverty relief of the county. 展开更多
关键词 Poverty-stricken county EXIT Evaluation Poverty incidence calculation method
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Comparison study on calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949 被引量:1
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作者 淳庆 Van Balen Koenraad 韩宜丹 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期529-534,共6页
In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, t... In order to study the calculation methods of bending behavior of Chinese reinforced concrete beams from 1912 to 1949, tests on the mechanical performance of 66 rebars from different modem Chinese concrete buildings, the concrete compressive strength of 12 modem Chinese concrete buildings, and the concrete cover thickness of 9 modem Chinese concrete buildings are carried out; and the actual material properties and structural conformations of modem Chinese concrete buildings are obtained. Then, the comparison on calculation methods of bending behavior including the original Chinese calculation method, the present Chinese calculation method, the present American calculation method and the present European calculation method is studied. The results show that the original Chinese calculation method of bending behavior is based on the allowable stress calculation method, and the design safety factors are 3.55 to 4. 0. In term of the calculation area of longitudinal rebars of reinforced concrete beams, without considering earthquake action, the original Chinese structural calculation method is safer than the present Chinese structural calculation method, the present European structural calculation method, and the present American structural calculation method. The results can provide support for the structural safety assessments of modem Chinese reinforced concrete buildings. 展开更多
关键词 reinforced concrete beam the Republic of China era from 1912 to 1949 bending behavior calculation method comparative study
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Simplified Calculation Methods for All-Vertical-Piled Wharf in Offshore Deep Water 被引量:3
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作者 WANG Yuan-zhan HE Lin-lin 《China Ocean Engineering》 SCIE EI CSCD 2017年第2期182-191,共10页
All-vertical-piled wharf is a kind of high-piled wharf, but it is extremely different from the traditional ones in some aspects, such as the structural property, bearing characteristics, failure mechanism, and static ... All-vertical-piled wharf is a kind of high-piled wharf, but it is extremely different from the traditional ones in some aspects, such as the structural property, bearing characteristics, failure mechanism, and static or dynamic calculation methods. In this paper, the finite element method (FEM) and theoretical analysis method are combined to analyze the structural property, bearing behavior and failure mode of the all-vertical-piled wharf in offshore deep water, and to establish simplified calculation methods determining the horizontal static ultimate bearing capacity and the dynamic response for the all-vertical-piled wharf. Firstly, the bearing capability and failure mechanism for all-vertical-piled wharf are studied by use of FEM, and the failure criterion is put forward for all-vertical-piled wharf based on the 'plastic hinge'. According to the failure criterion and P-Y curve method, the simplified calculation method of the horizontal static ultimate bearing capacity for all-vertical-piled wharf is proposed, and it is verified that the simplified method is reasonable by comparison with the FEM. Secondly, the displacement dynamic magnification factor for the all-vertical-piled wharf under wave cyclic loads and ship impact loads is calculated by the FEM and the theory formula based on the single degree of freedom (SDOF) system. The results obtained by the two methods are in good agreement with each other, and the simplified calculation method of the displacement dynamic magnification factor for all-vertical-piled wharf under dynamic loads is proposed. Then the simplified calculation method determining the dynamic response for the all-vertical-piled wharf is proposed in combination with P-Y curve method. That is, the dynamic response of the structure can be obtained through the static calculation results of P-Y curve method multiplied by the displacement dynamic magnification factor. The feasibility of the simplified dynamic response method is verified by comparison with the FEM under different conditions. 展开更多
关键词 all-vertical-piled wharf failure criterion plastic hinge dynamic amplification coefficient simplified calculation methods
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Thermal kinetic analysis of a complex process from a solid-state reaction by deconvolution procedure from a new calculation method and related thermodynamic functions of Mn_(0.90)Co_(0.05)Mg_(0.05)HPO_4?3H_2O 被引量:1
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作者 Chuchai SRONSRI Banjong BOONCHOM 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第9期1887-1902,共16页
Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative... Three individual peaks of thermal solid-state reaction processes of the synthesized Mn0.90Co0.05Mg0.05HPO4?3H2O were observed corresponding to dehydration I,dehydration II and polycondensation processes.An alternative method for the calculation of the extent of conversion was proposed from the peak area of the individual DTG peak after applying the best fitting deconvolution function(Frazer–Suzuki function).An iterative integral isoconversional equation was used to compute the values of the apparent activation energy Eαand they were found to be 65.87,78.16 and 119.32 kJ/mol for three peaks,respectively.Each individual peak was guaranteed to be a single-step kinetic system with its unique kinetic parameters.The reaction mechanism functions were selected by the comparison between experimental and model plots.The results show that the first,second and final individual peaks were two-dimensional diffusion of spherical symmetry(D2),three-dimensional diffusion of spherical symmetry(D3)and contracting cylinder(cylindrical symmetry,R2)mechanisms.Pre-exponential factor values of 3.91×106,1.35×107 and 2.15×107 s?1 were calculated from the Eαvalues and reaction mechanisms.The corresponded standard thermodynamic functions of the transition-state(activated)complexes were determined and found to agree well with the experimental data. 展开更多
关键词 solid-state reaction calculation method complex reaction Frazer–Suzuki function experimental and model plots
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A Calculation Method for Incidence and Reflection of Irregular Waves Along Seawalls
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作者 Zhu, LS Sui, SF 《China Ocean Engineering》 SCIE EI 1997年第3期305-314,共10页
Some researches have been made in this aspect. In the method by Walton Jr.(1992), incident waves are supposed to be the overlapping result of M component waves with different frequencies which may take different direc... Some researches have been made in this aspect. In the method by Walton Jr.(1992), incident waves are supposed to be the overlapping result of M component waves with different frequencies which may take different directions, the direction of incident waves should be available in advance, but in fact the direction of incident waves is not available. In our study, incident waves are supposed to be composed of M overlapping component waves with different frequencies, and different frequencies have different directions. Based on the irregular wave reflection theory, the calculation formulas of wave direction, complex amplitude of incident waves, and complex amplitude of reflected waves in surface which are composed of component waves are derived by means of discrete Fourier transform. Then, the frequency spectra of incident waves and reflected waves and the reflection coefficient of waves with corresponding frequencies are obtained. Verification of the method and the calculation results from in-situ measured data indicate that the method is reliable and highly accurate. 展开更多
关键词 irregular wave SEAWALL incidence and reflection calculation method
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A study of laboratory testing and calculation methods for coal sorption isotherms
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作者 Lei ZHANG Ting-Xiang REN Nai AZIZ 《Journal of Coal Science & Engineering(China)》 2013年第2期193-202,共10页
Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testin... Measurement of the volume of gas adsorbed per unit mass of coal with increasing pressure at a constant temperature produces an isotherm that describes the gas storage capacity of this type of coal. The accurate testing and interpretation of coal sorption isotherm plays an important role in the areas of coal mine methane drainage, coalbed methane (CBM) reservoir resource assessment, enhanced coalbed methane (ECBM) recovery, as well as the carbon dioxide (CO2) sequestration in deep coal seams or similar geological formations. Different coal sorption isotherm testing apparatus and associated calculation methods are critically reviewed and presented in this paper. These include both volumetric and gravimetric based methods, as well as experimental sorption tests with confining stress and direction sorption methods. The volumetric techniques utilise experimental apparatus with sample cell and injection pump and that with both sample cell and reference cell. Whilst the gravimetric approachesinclude methods with sample cell and suspension magnetic balance and that with both sample cell and reference cell. Different testing methods are compared and discussed in this study. A unique in-house-built coal sorption isotherm testing apparatus at the University of Wollongong was presented together with the calculation method, procedures and experimental results. The isotherm results can be calculated by both Soave-Redlich-Kwong (SRK) equation and calibration cure methods which can be used directly to convert the volume of adsorbed gas in different test conditions to standard condition (NTP). 展开更多
关键词 sorption isotherm coalbed methane coal mine gas apparatus calculation method volumetric method gravimetric method
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SELECTING CLUSTER MODEL IN Sn - BASED SOLDER ALLOY DESIGN WITH DV - X_α CALCULATION METHOD
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作者 C. Q. Wang and W. F. Feng National ho. of Advanced welding Technolgy, HIT, Harbin 150001,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期84-88,共5页
Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ... Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail. 展开更多
关键词 Cluster model Sn - based alloy design DV - X_a calculation method DOS
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Study on calculation method of surface subsidence about the dewatering concretion of clay influenced by mining
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作者 温兴林 朱学军 +1 位作者 常西坤 郭惟嘉 《Journal of Coal Science & Engineering(China)》 2007年第4期512-515,共4页
Under the condition of thick alluvia, there is biggish declination in predicting the coal mining subsidence by commonly strip design method compared with the practical observation, the sinkage is much smaller. Based o... Under the condition of thick alluvia, there is biggish declination in predicting the coal mining subsidence by commonly strip design method compared with the practical observation, the sinkage is much smaller. Based on the method of the probability integral about coal mining subsidence calculation, discussed the surface subsidence calculation and deduced the formulas caused by the clay with dewatering. The results show that the clay dewatering has great impact on surface subsidence. Therefore, the clay dewatering on surface subsidence should not be overlooked. 展开更多
关键词 CLAY surface subsidence dewatering concretion calculation method
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Preliminary Study on the Calculation Method of “Carbon Footprint”
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作者 YU Man, PENG Wan-gui, GE Da-bing College of Bioscience and Biotechnology, Institute of Ecology, Hunan Agricultural University, Changsha 410128, China 《Meteorological and Environmental Research》 CAS 2011年第4期9-11,21,共4页
At present, greenhouse effect has become a severe challenge of international society. In order to cope with this challenge, countries all over the world reached an agreement to develop low-carbon economy and create lo... At present, greenhouse effect has become a severe challenge of international society. In order to cope with this challenge, countries all over the world reached an agreement to develop low-carbon economy and create low-carbon society. As a new concept, 'carbon footprint' emerged with the vigorous development of low-carbon economy, and its calculation method is related to the evaluation system of low carbon economy. In order to calculate 'carbon footprint', 'carbon subject' in the study was divided into energy consumption account, soil respiration account and biological resources account, and the calculation formula of 'carbon footprint' was defined, as well as CO2 emission from various accounts, namely the calculation method of 'carbon footprint' was discussed preliminarily from quantitative evaluation index. 展开更多
关键词 Low-carbon economy CO2 Carbon footprint calculation method China
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Comparison of Calculation Methods for Potential Reference Crop Evapotranspiration ET_0 in North Xinjiang
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作者 Chunyan YIN Hu LIU +2 位作者 Ruiqiang ZHANG Jian WANG Yongfu WEI 《Agricultural Science & Technology》 CAS 2017年第5期920-923,共4页
Reference crop evapotranspiration (ET_0) is a critical part in water cycle and water balance of ecosystem, which is greatly important to effective utilization of agricultural water resources and for making reasonable ... Reference crop evapotranspiration (ET_0) is a critical part in water cycle and water balance of ecosystem, which is greatly important to effective utilization of agricultural water resources and for making reasonable irrigation system. In order to propose a suitable method for computing ET_0 in North Xinjiang, based on daily meteorological data from May 1 to September30, 2010 provided by Weather Station of Fuhai County, we used FAO56 Penman-Monteith as the standard formula to compute ET_0, compared the differences and relations between such the method and other 4 calculation formulas, and analyzed the cause of the deviation, finally evaluated the applicability of computational method in North Xinjiang. The results showed that the calculation results by FA056 PM Method was approximate to that by FAO Penman method and IA method, of which the relative error was 9.26% and 13.51% respectively, the ET_0 results calculated by PT method and HS method were generally greater than the results by FAO56 PM, and their deviation was very obvious. 展开更多
关键词 North Xinjiang Reference crop evapotranspiration calculation method FAO56 PM
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A calculation method of the sensible heat flux by sodar
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作者 Lu Naiping, Li Shiming, Chen Jingnan, Zheng Yueming Zhou Mingyu National Recsearch Center for Marine Environmcntul Forecasts, Beijing, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第2期191-198,共8页
During the second course of USA - PRC joint air sea interaction experiment in 1986, the temperature structure parameters CT2 were measured by sodar over the Western Pacific Ocean. Based on similarity theory, a method ... During the second course of USA - PRC joint air sea interaction experiment in 1986, the temperature structure parameters CT2 were measured by sodar over the Western Pacific Ocean. Based on similarity theory, a method is discussed to calculate the sensible heat flux over the ocean in unstable stratification. Becausehumidity is great over the ocean, so we have to consider the influence of water vapor structure parameter Ce2and the correlation coefficient betweene and T on the calculation of sensible heat flux using CT2 profiles measured by sodar. A new formula is suggested in terms of parameterization. The sensible heat flux calculated by sodar measurements is compared with that by bulk transfer method, and the results agree well. 展开更多
关键词 HEAT A calculation method of the sensible heat flux by sodar
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A Review of the Calculation Methods of Lifting Capacity in Wind Loads on Ocean Platforms
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作者 Yuchen Sheng 《Open Journal of Marine Science》 2021年第2期69-79,共11页
Wind load is a control load that affects the safety of structures in the design of ocean platforms. It has not only direct and powerful effects that may cause structure resonance but also has indirect effects causing ... Wind load is a control load that affects the safety of structures in the design of ocean platforms. It has not only direct and powerful effects that may cause structure resonance but also has indirect effects causing waves or currents in the ocean. By analyzing the domestic and international norms, this study <span style="letter-spacing:0.1pt;font-family:Verdana;font-size:12px;">pre</span><span style="font-family:Verdana;font-size:12px;">sents a review of calculation methods of wind load on ocean platforms, which </span><span style="letter-spacing:-0.15pt;font-family:Verdana;font-size:12px;">belongs to large-scale non-entity structure used in the open sea while sur</span><span style="font-family:Verdana;font-size:12px;">round</span><span style="letter-spacing:-0.1pt;font-family:Verdana;font-size:12px;">ing wind has no fixed direction. Current computations according to the</span><span style="font-family:Verdana;font-size:12px;"> norms are not accurate, which even not takes the force of the wind against the surf</span><span style="letter-spacing:-0.1pt;font-family:Verdana;font-size:12px;">ace perpendicular to the structure into consideration. Additionally, thi</span><span style="font-family:Verdana;font-size:12px;">s study also introduces and compares the lift model of platforms based on different </span><span style="letter-spacing:-0.1pt;font-family:Verdana;font-size:12px;">theories, such as vortex-excitation and vibration, engineering structure dy</span><span style="font-family:Verdana;font-size:12px;">namics, gas flow pressure theory, analyzing their applicability, advantages, and disadvantages. This paper analyzes the limitations and applicable conditions of the existing calculation method itself, such as the lift model is suitable for the existence of stable vortex wake;the calculation method of the structural dynamics of marine engineering must be combined with the wind tunnel test and consider the mistakes caused by the position relationship;the numerical simulation method is accurate but tedious. This study provides an insight into the calculation methods of lift in designing ocean platforms, including the </span><span style="letter-spacing:0.1pt;font-family:Verdana;font-size:12px;">finite element method for simulating fluid force and updating formulas in</span><span style="font-family:Verdana;font-size:12px;"> Chinese norms.</span> 展开更多
关键词 LIFT Wind Load calculation method Lift Model Structural Dynamics Vortex-Excitation
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A NEW AB INITIO CALCULATION METHOD OF INNER-SPHERE REORGANIZATION ENERGY
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作者 Yu Xiang BU Xin Yu SONG Yu Hua ZHANG(Department of Chemistry. Qufu Normal University,Qufu,273165) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第6期491-494,共4页
On the basis of the-improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G* and DZP levels a new calculation method was,presented for the i... On the basis of the-improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G* and DZP levels a new calculation method was,presented for the inner-sphere reorganization energy, values for diatomic molecular redox couples in gas phase electron transfer process have been calculated. Results agree well with the experimental data, and the effectiveness and importance of this method have been demonstrated for calculation of inner-sphere reorganization energy in gas phase electron transfer process. 展开更多
关键词 AB A NEW AB INITIO calculation method OF INNER-SPHERE REORGANIZATION ENERGY
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A Calculation Method of Profile Error Influenced by Tool Error for Two-Axis Coordinated CNC Machining of a Spatial Barrel-Cam
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作者 YIN Ming-Fu, LU Chuan-Yi, CHEN Jin-Kui Xi’an University of Technology, Xi’an 710048, P. R. China Shandong Institute of Technology, Zibo 255012, P. R. China 《International Journal of Plant Engineering and Management》 2001年第2期92-97,共6页
Taking the CNC machining for the spatial barrel-cam with rectilinear translating and a conical roller follower as an example, the calculation method and the law of the profile error influenced by the tool error is given.
关键词 spatial barrel-cam CNC machining profile error calculation method
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Study on Calculation Method of Compressional Velocities Based on Field Well Logs
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作者 Feizhou Shi Yanchun Wang Xueqing Liu 《International Journal of Geosciences》 2016年第7期928-937,共10页
In the past, most of the studies for compressional velocities are based on experimental measurements, which lack the support of field data. The purpose of this study is to estimate the compressional velocities based o... In the past, most of the studies for compressional velocities are based on experimental measurements, which lack the support of field data. The purpose of this study is to estimate the compressional velocities based on well log data of delta front subfacies of Lower Tertiary ages of Ji-Dong oil field, China. At initial stage, we have chosen the well log parameters (effect factors) which strongly influence on compressional velocities and established a new modified equation for compressional velocities, which is based on these effect factors. Then Gardner, De-hua Han and this newly established equation were utilized to calculate the compressional velocities in each well. Finally, Least-square regression was carried out to check the fitting of each equation. Regression results clearly indicate that our purposed equation shows better fitting as compared to Gardner and De-hua Han equations. 展开更多
关键词 Compressional Velocities Well Logs calculation method
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Asymmetrical Fault Current Calculation Method and Influencing Factors Analysis of Droop-Controlled Inverters 被引量:1
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作者 Huimin Zhao Zhikang Shuai +3 位作者 Jun Ge An Luo Weimin Wu Z.John Shen 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2024年第2期562-573,共12页
Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten th... Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method. 展开更多
关键词 Asymmetrical fault analysis droop control fault current calculation method LIMITER transient fault characteristics
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Study on carbon emission calculation method and carbon reduction indexes of urban building stock
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作者 YANG Liu ZHANG Nan +2 位作者 LU Mei LUO ZhiXing DOU Mei 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2024年第9期2706-2726,共21页
Carbon emissions associated with buildings are a major source of urban emissions. To put forward the methods and strategies to curb carbon emissions from urban building stock, it is not only necessary to establish a c... Carbon emissions associated with buildings are a major source of urban emissions. To put forward the methods and strategies to curb carbon emissions from urban building stock, it is not only necessary to establish a carbon emission calculation method for fine statistical analysis, but also to evaluate carbon emissions of urban planning schemes with applicable indexes. Currently,researches mainly focus on carbon emissions of individual buildings. When expanded to urban building stock, the calculation faces the lack of basic data, inadequate spatial analysis and unspecific carbon reduction indexes. Therefore, this study proposes a bottom-up calculation method for urban building stock, conducts spatial analysis based on carbon balance of urban grids, reveals the coupling mechanism between urban carbon reduction indexes and grid carbon emissions, and systematically establishes a carbon-reduction-oriented urban planning method that comprises calculation, analysis and evaluation, which is applied to Xi'an,China. This study provides a theoretical reference for cities to formulate carbon reduction targets and implement planning strategies by evaluating and predicting carbon emissions from urban building stock. 展开更多
关键词 carbon emissions urban building stock calculation method carbon reduction index
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Rainfall Threshold Calculation Method for Debris Flow Pre-Warning in Data-Poor Areas 被引量:2
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作者 潘华利 黄江成 +1 位作者 汪稔 欧国强 《Journal of Earth Science》 SCIE CAS CSCD 2013年第5期854-862,共9页
Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important ... Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important component of debris flows and is the most active factor when debris flows oc- cur. Rainfall also determines the temporal and spatial distribution characteristics of the hazards. A reasonable rainfall threshold target is essential to ensuring the accuracy of debris flow pre-warning. Such a threshold is important for the study of the mechanisms of debris flow formation, predicting the characteristics of future activities and the design of prevention and engineering control measures. Most mountainous areas have little data regarding rainfall and hazards, especially in debris flow forming re- gions. Therefore, both the traditional demonstration method and frequency calculated method cannot satisfy the debris flow pre-warning requirements. This study presents the characteristics of pre-warning regions, included the rainfall, hydrologic and topographic conditions. An analogous area with abundant data and the same conditions as the pre-warning region was selected, and the rainfall threshold was calculated by proxy. This method resolved the problem of debris flow pre-warning in ar- eas lacking data and provided a new approach for debris flow pre-warning in mountainous areas. 展开更多
关键词 rainfall threshold debris flow pre-warning calculation method data lack area.
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An improved calculation method for fiber Raman amplifier equations with multi-wavelength pumping 被引量:3
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作者 常建华 张明德 孙小菡 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第8期441-444,共4页
A novel numerical method for fiber Raman amplifier (FRA) from standard propagation equations is presented and derived based on the one-step method for ordinary differential equation (ODE). The proposed algorithm is ef... A novel numerical method for fiber Raman amplifier (FRA) from standard propagation equations is presented and derived based on the one-step method for ordinary differential equation (ODE). The proposed algorithm is effective in solving FRA equations including all the interactions among pumps, signals, and noises. Applications of the numerical analysis to practical FRA-based systems show a great reduction in computation time in comparison with the average power method and the fourth-order Runge-Kutta (RK) method, under the same condition. Also the proposed method can decrease the computing time over three orders of magnitude with excellent accuracy promises in comparison with the direct integration method. 展开更多
关键词 LENGTH FRA An improved calculation method for fiber Raman amplifier equations with multi-wavelength pumping
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A rapid calculation method for predicting roll deformation of six-high rolling mill 被引量:2
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作者 Li Xie An-rui He Chao Liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第9期901-909,共9页
The method to predict roll deformation precisely and efficiently is vital for the strip shape control of a six-high rolling mill. Traditional calculation methods of roll deformation, such as the finite element method ... The method to predict roll deformation precisely and efficiently is vital for the strip shape control of a six-high rolling mill. Traditional calculation methods of roll deformation, such as the finite element method and the influence function method, have been widely used due to their accuracies. However, the required calculation time is too long to be applied to the realtime control. Therefore, a rapid calculation method for predicting roll deformation of a six-high rolling mill was proposed, which employed the finite difference method to calculate the roll deflection and used a polynomial to describe the nonlinear relationship between roll flattening and roll contact pressure. Furthermore, a new correction strategy was proposed in the iteration, where the roll center flattening and the roll flattening deviation were put forward and corrected simultaneously in the iteration process according to the static equilibrium of roll. Finally, by the comparison with traditional methods, the proposed method was proved to be more efficient and it was suitable for the online calculation of the strip shape control. 展开更多
关键词 Six-high rolling mill Roll deformation Influence function method Rapid calculation method Online model
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