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A pre-warning system of abnormal energy consumption in lead smelting based on LSSVR-RP-CI 被引量:2
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作者 WANG Hong-cai FANG Hong-ru +1 位作者 MENG Lei XU Feng-xiang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2175-2184,共10页
The pre-warning of abnormal energy consumption is important for energy conservation of industrial engineering. However, related studies on the lead smelting industries which usually have a huge energy consumption are ... The pre-warning of abnormal energy consumption is important for energy conservation of industrial engineering. However, related studies on the lead smelting industries which usually have a huge energy consumption are rarely reported. Therefore, a pre-warning system was established in this study based on the intelligent prediction of energy consumption and the identification of abnormal energy consumption. A least square support vector regression (LSSVR) model optimized by the adaptive genetic algorithm was developed to predict the energy consumption in the process of lead smelting. A recurrence plots (RP) analysis and a confidence intervals (CI) analysis were conducted to quantitatively confirm the stationary degree of energy consumption and the normal range of energy consumption, respectively, to realize the identification of abnormal energy consumption. It is found the prediction accuracy of LSSVR model can exceed 90% based on the comparison between the actual and predicted data. The energy consumption is considered to be non-stationary if the correlation coefficient between the time series of periodicity and energy consumption is larger than that between the time series of periodicity and Lorenz. Additionally, the lower limit and upper limit of normal energy consumption are obtained. 展开更多
关键词 lead smelting energy consumption least square support vector regression (LSSVR) recurrence plots (RP) confidence intervals (CI)
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Comparison study of typical algorithms for reconstructing time series from the recurrence plot of dynamical systems 被引量:1
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作者 刘杰 石书婷 赵军产 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期131-137,共7页
The three most widely used methods for reconstructing the underlying time series via the recurrence plots (RPs) of a dynamical system are compared with each other in this paper. We aim to reconstruct a toy series, a... The three most widely used methods for reconstructing the underlying time series via the recurrence plots (RPs) of a dynamical system are compared with each other in this paper. We aim to reconstruct a toy series, a periodical series, a random series, and a chaotic series to compare the effectiveness of the most widely used typical methods in terms of signal correlation analysis. The application of the most effective algorithm to the typical chaotic Lorenz system verifies the correctness of such an effective algorithm. It is verified that, based on the unthresholded RPs, one can reconstruct the original attractor by choosing different RP thresholds based on the Hirata algorithm. It is shown that, in real applications, it is possible to reconstruct the underlying dynamics by using quite little information from observations of real dynamical systems. Moreover, rules of the threshold chosen in the algorithm are also suggested. 展开更多
关键词 recurrence plot chaotic system time series analysis correlation analysis
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Electrical Load Forecasting Using Fuzzy System 被引量:1
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作者 Mahir Faysal Md. Jahirul Islam +2 位作者 Md. Mohiuddin Murad Md. Imdadul Islam M. Ruhul Amin 《Journal of Computer and Communications》 2019年第9期27-37,共11页
To cope with the demand and supply of electrical load of an interconnected power system of a country, we need to forecast its demand in advance. In this paper, we use a fuzzy system to forecast electrical load on shor... To cope with the demand and supply of electrical load of an interconnected power system of a country, we need to forecast its demand in advance. In this paper, we use a fuzzy system to forecast electrical load on short-term basis. Here, we consider temperature, humidity, seasons of a year and time segments of a day as the parameters, which govern the demand of electrical load. For each of the parameter, we use several membership functions (MFs) and then apply the Mamdani rule on MFs and the output is determined by using the centroid method. Finally, the surface plot reveals the real scenario of the load demand. The difference between actual load and the output of the fuzzy system is found as +1.65% to -13.76%. The concept of the paper can be applied in interconnected power system of Bangladesh to reduce power loss, especially when generation is higher than the demand. 展开更多
关键词 DEFUZZIFICATION FUZZY INFERENCE CENTROID Method Surface PLOT APE
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Feature Recognition and Selection Method of the Equipment State Based on Improved Mahalanobis-Taguchi System 被引量:1
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作者 WANG Ning ZHANG Zhuo 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第2期214-222,共9页
Mahalanobis-Taguchi system(MTS)is a kind of data mining and pattern recognition method which can identify the attribute characteristics of multidimensional data by constructing Mahalanobis distance(MD)measurement scal... Mahalanobis-Taguchi system(MTS)is a kind of data mining and pattern recognition method which can identify the attribute characteristics of multidimensional data by constructing Mahalanobis distance(MD)measurement scale.In this paper,considering the influence of irregular distribution of the sample data and abnormal variation of the normal data on accuracy of MTS,a feature recognition and selection model of the equipment state based on the improved MTS is proposed,and two aspects of the model namely construction of the original Mahalanobis space(MS)and determination of the threshold are studied.Firstly,the original training sample space is statistically controlled by the X-bar-S control chart,and extreme data of the single characteristic attribute is filtered to reduce the impact of extreme condition on the accuracy of the model,so as to construct a more robust MS.Furthermore,the box plot method is used to determine the threshold of the model.And the stability of the model and the tolerance to the extreme condition are improved by leaving sufficient range of the variation for the extreme condition which is identified as in the normal range.Finally,the improved model is compared with the traditional one based on the unimproved MTS by using the data from the literature.The result shows that compared with the traditional model,the accuracy and sensitivity of the improved model for state identification can be greatly enhanced. 展开更多
关键词 Mahalanobis-Taguchi system(MTS) EXTREME condition X-bar-S control CHART BOX PLOT method Mahalanobis space(MS) Mahalanobis distance(MD) threshold feature recognition equipment STATE
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Technical efficiency and its determinants of the various cropping systems in the purple-soiled,hilly region of southwestern China 被引量:2
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作者 ZHANG Shi-chao WEI Chao-fu +1 位作者 SHAO Jing-an WU Zhao-juan 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2205-2223,共19页
This study examines the technical efficiency(TE) differences among typical cropping systems of smallholder farmers in the purple-soiled hilly region of southwestern China.Household-,plot-,and crop-level data and commu... This study examines the technical efficiency(TE) differences among typical cropping systems of smallholder farmers in the purple-soiled hilly region of southwestern China.Household-,plot-,and crop-level data and community surveys were conducted to explore TE levels and determinants of typical cropping systems by using a translog stochastic frontier production function.Results indicate significant difference in TE and its determinants among cropping systems.The mean TEs of the rice cropping system(R),the rice-rape cropping system(RR),the rice-rape-potato cropping system(RRP),and the oil cropping system(O) are0.86,0.90,0.84,and 0.85,respectively,which are over 1.17 times higher than those of the maize-sweet potato-other crop cropping system(MSO) and the maize-sweet potato-wheat cropping system(MSW) at0.78 and 0.69,respectively.Moreover,Technical inefficiency(TIE) of different cropping systems is significantly affected by characteristics of the household as well as plot.However,the impact of land quality,mechanical cultivation conditions,crop structure,farming system,farm radius,household type,cultivated land area per capita,and annual household income per capitalon TIE vary by cropping system.Additionally,output elasticity of land,labor,and capital,as a group,is greater than the one of agricultural machinery and irrigation.Finally,when household-owned effective agricultural labor is at full farming capacity,optimal plot sizes for the R,RR,RRP,MSO,MSW,and 0 cropping systems are 1.12hm^2,0.35 hm^2,0.25 hm^2,2.82 hm^2,1.87 hm^2,and 1.17hm^2,respectively. 展开更多
关键词 Cropping systems Technical efficiency Land management Plot Purple-soil Stochastic Frontier Production Function
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Geoelectrical structures of northern segment of Tan-Lu fault system in China and Russia areas based on magnetotelluric soundings 被引量:1
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作者 V.B.Kaplun G.L.Kirillova LI Tonglin 《Global Geology》 2013年第3期164-174,共11页
From China to Russia,Tan-Lu fault system stretches for thousands of kilometers,towards NE 30°.The authors have collected more than ten magnetotelluric profile that China and Russia have carried out,in the studied... From China to Russia,Tan-Lu fault system stretches for thousands of kilometers,towards NE 30°.The authors have collected more than ten magnetotelluric profile that China and Russia have carried out,in the studied area of the Tan-Lu fault's northern section,and have analyzed electrical characteristics of the relevant profiles.Deriving the following conclusions:(1)Jiamusi-Bureya plots,etc.,demonstrate the high resistance of Kernel;(2)Fold belt attributed to the land showed high and low resistance stitching,associated with not only terrane accretion,but also upper mantle upwelling;below the sedimentary basin,the resistivity of the upper mantle is lower and closer to the surface comparing with the adjacent area(100-150);(3)In the system of Tan-Lu fracture,Yishu and Dunmi fracture,etc.are expressed as vertical low-resistivity zone;(4)There may exist subducted old-fashioned piece under Jiamusi and Bureya plots. 展开更多
关键词 magnetotelluric sounding Tan-Lu fault system plates upwelling mantle PLOTS
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COMPUTER SYSTEM FOR GEOMETRIC MODELING OF GEOLOGIC BODIES AND APPLICATIONS
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作者 Dai, Tagen Mao, Xiancheng 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第4期179-184,共6页
INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1].... INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1].Bymeansofcomput... 展开更多
关键词 GEOLOGIC BODY data structure MATHEMATICAL model automatic plotting
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An Intelligent Process Fault Diagnosis System based on Andrews Plot and Convolutional Neural Network 被引量:1
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作者 Shengkai Wang Jie Zhang 《Journal of Dynamics, Monitoring and Diagnostics》 2022年第3期127-138,共12页
This paper proposes an intelligent process fault diagnosis system through integrating the techniques of Andrews plot and convolutional neural network.The proposed fault diagnosis method extracts features from the on-l... This paper proposes an intelligent process fault diagnosis system through integrating the techniques of Andrews plot and convolutional neural network.The proposed fault diagnosis method extracts features from the on-line process measurements using Andrews function.To address the uncertainty of setting the proper dimension of extracted features in Andrews function,a convolutional neural network is used to further extract diagnostic information from the Andrews function outputs.The outputs of the convolutional neural network are then fed to a single hidden layer neural network to obtain the final fault diagnosis result.The proposed fault diagnosis system is compared with a conventional neural network based fault diagnosis system and integrating Andrews function with neural network and manual selection of features in Andrews function outputs.Applications to a simulated CSTR process show that the proposed fault diagnosis system gives much better performance than the conventional neural network based fault diagnosis system and manual selection of features in Andrews function outputs.It reveals that the use of Andrews function and convolutional neural network can improve the diagnosis performance. 展开更多
关键词 Andrews plot convolutional neural network fault diagnosis neural network
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Signal Filtering in Multizone Systems of Image Analysis of Image Analysis
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作者 贝柯夫RE 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期166-178,共13页
Principles of color space generation for multizone optical registration systems are presented;conformity between different color spaces is defined;algo- rithms of the multizone image registrator signal processing and ... Principles of color space generation for multizone optical registration systems are presented;conformity between different color spaces is defined;algo- rithms of the multizone image registrator signal processing and a generalized algo- rithm for analysis are given.Procedures are discussed for plotting the color spaces that are used in the analysis of the Earth and other planets.It is shown that estimates made in such spaces are interrelated and that spectral reflections of objects under study should be available in order to compare—in terms of color discrimination- several automatic recorders with different spectral sensitivities.Examples are given to illustrate color spaces having such properties.Circuits of chromaticity filters are also presented. 展开更多
关键词 SIGNALS signal processing algorithm/spectral characteristics of radiation color space plotting signal filtering
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Multifunctional Measurement System for High Precision Planetary Servo Gearhead
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作者 FAN Shuqian ZHANG Lili +1 位作者 WANG Lei SHI Mingquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第2期398-404,共7页
As an essential component of a servo system,mechanical properties of high precision planetary servo gearhead direct influence on the validation,stability and accuracy of the servo control system.However,mechanical pro... As an essential component of a servo system,mechanical properties of high precision planetary servo gearhead direct influence on the validation,stability and accuracy of the servo control system.However,mechanical properties measurement and assessment for high precision planetary servo gearhead is a time-consuming and tedious work,since current methodologies typically rely on various different specified systems.An integrated multifunctional measurement system SFJC-I is developed,which employs a torque sensor and a laser displacement transducer to simultaneously measure torque applied on servo gearhead and its corresponding torsional deformation.The measurement system depends on the accurate measurement of the relative displacement between input clamping system and output shaft of servo gearhead with a lever-type enlarging mechanism,rather than traditional optical dividing head and optical multisurface prism.Using interchangeable fixture system,the developed system capability to measure almost all series and specifications of high precision planetary servo gearhead is demonstrated.With proposed hardware platform configuration and developed measuring software,mechanical properties such as backlash,torsional stiffness,hysteresis plot and emergency stop torque,can be measured accurately and assessed reliably.A torsion test with standard circular specimen is carried out with the multifunctional measurement system.The result of test shows that the measurement error is within ±3σ and the measurement reliability is more than 99.97%.The problem of accurate measurement and reliable assessment of mechanical properties for high precision planetary servo gearhead is fully solved with the developed multifunctional measurement system. 展开更多
关键词 servo gearhead measurement hysteresis plot emergency stop torque
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Parameter Identification of Structural Nonlinearity by Using Response Surface Plotting Technique
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作者 LIU Xin WANG Lixiao +1 位作者 CHEN Qidong SUN Beibei 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第6期819-827,共9页
With rigorous dynamic performance of mechanical products,it is important to identify dynamic parameters exactly.In this paper,a response surface plotting method is proposed and it can be applied to identify the dynami... With rigorous dynamic performance of mechanical products,it is important to identify dynamic parameters exactly.In this paper,a response surface plotting method is proposed and it can be applied to identify the dynamic parameters of some nonlinear systems.The method is based on the principle of harmonic balance method(HBM).The nonlinear vibration system behaves linearly under the steady-state response amplitude,which presents the equivalent stiffness and damping coefficient.The response surface plot is over two-dimensional space,which utilizes excitation as the vertical axis and the frequency as the horizontal axis.It can be applied to observe the output vibration response data.The modal parameters are identified by the response surface plot as linearity for different excitation levels,and they are converted into equivalent stiffness and damping coefficient for each resonant response.Finally,the HBM with first-order expansion is utilized for identification of stiffness and damping coefficient of nonlinear systems.The classical nonlinear systems are applied in the numerical simulation as the example,which is used to verify its effectiveness and accuracy.An application of this technique for nonlinearity identification by experimental setup is also illustrated. 展开更多
关键词 structural nonlinearity parameter identification equivalent stiffness and damping response surface plot
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Moisture Migration and Bulk Nutrients Interaction in a Drying Food Systems: A Review
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作者 Israel Sunmola Afolabi 《Food and Nutrition Sciences》 2014年第8期692-714,共23页
Drying is a technique that involves removal of moisture using heat energy. This heat affects the protein components in foods especially the thiosulphide groups, which causes hydrophobic bond break that has been attrib... Drying is a technique that involves removal of moisture using heat energy. This heat affects the protein components in foods especially the thiosulphide groups, which causes hydrophobic bond break that has been attributed greatly to denaturation during drying. Safe moisture content (SMC) is the extent to which moisture can be withdrawn from food crops during drying that such crops can be considered safe for storage with minimal loss of nutritional qualities. Several reported minimum moisture contents, and bulk nutrients’ levels of crops were collected for the purpose of this review, and scattered plot graph was employed to determine the levels of bond interaction between moisture content and each bulk nutrients in the various dried food categories. The moisture contents in grains, root and tuber crops, fruits and vegetables, and cash crops formed a SMC threshold boundary within the 6% - 14%;0% - 10%;0% - 22%;and 0% - 30% respectively. Crude fibre and most especially the ash content played the most crucial role by providing the strongest bond interaction with migrating moisture during drying of all the food crops’ categories, and are of utmost important in the determination of SMC. 展开更多
关键词 PRESERVATION Safe Moisture Content SCATTERED PLOT Threshold Boundary BONDS
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Predicting Yield and Stability Analysis of Wheat under Different Crop Management Systems across Agro-Ecosystems in India
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作者 Mangi Lal Jat Raj Kumar Jat +6 位作者 Parvinder Singh Shankar Lal Jat Harminder Singh Sidhu Hanuman Sahay Jat Deepak Bijarniya Chiter Mal Parihar Raj Gupta 《American Journal of Plant Sciences》 2017年第8期1977-2012,共36页
The objectives of the study were as follows: 1) to evaluate the GxExM for wheat genotypes;2) to predict yield performance and identify high stable wheat genotypes in different management practices;and 3) to make genot... The objectives of the study were as follows: 1) to evaluate the GxExM for wheat genotypes;2) to predict yield performance and identify high stable wheat genotypes in different management practices;and 3) to make genotype-specific management and high performing genotype recommendations within and across agro-ecological regions. A diverse set of twenty-one genotypes was evaluated over three years (2012, 2013 and 2014) under two levels of crop management practices (CT and ZT) across three agro-ecological regions (BR, MP and PB) of India in replicated trials. Data were analyzed with SASGxE and RGxE programs using SAS and R programming languages, respectively. Across and within a location(s), the pattern of GxExM and GxMxY interactions (respectively) among univariate and multivariate stability statistics, grouping of genotypes in divisive clusters and estimates (with a prediction interval) of genotype varied in management practice CT and ZT. Across locations, the genotypes “Munal” and “HD-2967” were the best performers and high stable in CT and ZT, respectively. Genotypes “HD-2824” and “DPW-621-50”, and “Munal” may serve as diverse parents for developing high quality, climate smart, locally adapted genotypes for BR in CT and ZT, respectively. Genotypes “HD-2932”, “BAZ” and “JW-3288”, and “GW-322” and “HD-2967” are suitable for developing locally adapted stress tolerant genotypes for MP in management practices CT and ZT, respectively. Relatively small GxM and GxExM interactions in PB preclude in making definitive conclusions. 展开更多
关键词 STABILITY Analysis GxExM BLUPs Forest PLOTS GGE BIPLOT WHEAT Univariate STABILITY STATISTICS
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Assessment and Inventory of Forest Ecosystems Biodiversity: Case Study for Karelian Isthmus of Leningrad Region, Russia
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作者 Alexander S. Alekseev 《Open Journal of Ecology》 2018年第5期305-323,共19页
Regular grid of permanent sample plots (PSP) of ICP-Forests monitoring system was used for forest ecosystems biodiversity assessments and inventory. The supplementary features were added to the PSP structure to conduc... Regular grid of permanent sample plots (PSP) of ICP-Forests monitoring system was used for forest ecosystems biodiversity assessments and inventory. The supplementary features were added to the PSP structure to conduct biological diversity census: eight sample plots 1 × 1 m for geo-botanical description;two sample plots of 5 × 5 m each for description of the PSP’s undergrowth;one 25 × 25 m plot for coarse woody debris estimations;four soil inventory pits. The total number of PSP amounted to 248. Total data used are as following: 1) 1984 geo-botanical descriptions of vegetation belonging to ground cover layers made on 1 × 1 m sample plots;2) 496 descriptions of undergrowth on 5 × 5 m sample plots;3) 178 descriptions of woody debris on 25 × 25 m sample plots;4) 496 descriptions of soil inventory pits. General statistical indicators characterizing forest land cover diversity were calculated. Statistic indicators of α-diversity for the Karelian Isthmus forest vegetation cover have the following values: 1) m (mean number of species per PSP) = 26 species;2) σ (standard deviation) = 9.5 species;3) v (variation coefficient) = 36.5%;4) Р (deviation amplitude) = 60 – 7 = 53 species. β – diversity of forest ecosystems as well as γ – diversity also was studied on the base of information collected on the same regular grid of sample plots. It appears that sample plots distribution by species diversity gradation is well described by the standard curve of normal distribution for the entire Karelian Isthmus forest (determination coefficient of the curve being 95.2%) as well as for each type of forest. Hence, the criterion (standard) of biodiversity for forest ecosystems can be defined as the mean value of alpha diversity for each forest type group – m;and the standard deviation – σ, as a tool for assessing deviations from the standard. PSP locations are fixed using GPS technology, this allows biodiversity assessments at the same place in the next years for biodiversity trends estimations and consist the frame for systematic biodiversity inventory. 展开更多
关键词 Plant BIODIVERSITY ICP-Forests Program Forest ECOsystemS α- β- γ-Diversity Regular Grid of Sample PLOTS BIODIVERSITY Standards.
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PID Stabilization of Linear Neutral Time-Delay Systems in a Numerical Approach
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作者 Hassan Farokhi Moghadam Nastaran Vasegh Seyed Zeinolabedin Moussavi 《Intelligent Control and Automation》 2012年第4期313-318,共6页
In this paper, the stabilization of neutral time-delay systems is investigated. An efficient numerical approach is presented in an algorithm to establish results so that stability of such systems is achieved and stabi... In this paper, the stabilization of neutral time-delay systems is investigated. An efficient numerical approach is presented in an algorithm to establish results so that stability of such systems is achieved and stabilizing PID parameters are determined directly. It is based on determining the rightmost characteristic roots and Nyquist plot. The Newton-Raphson’s iterative method based on Lambert W function is used for the calculation of these stabilizing roots directly from the closed-loop characteristic equation of the neutral time-delay system and then stability is checked by Nyquist plot and step response of closed-loop system. Two numerical examples are included to illustrate the effectiveness of the proposed approach. 展开更多
关键词 NEUTRAL TIME-DELAY systems PID Controller Stability Iterative Method Rightmost Characteristic Root NYQUIST PLOT
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Study on Surface Plotting Methods in Parts Plotting
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作者 LIU Zhen ZHAO Fa-dong 《Computer Aided Drafting,Design and Manufacturing》 2013年第2期44-47,共4页
According to the factors that confirm the shape of surface, it is classified into two categories: arc surface and curve surface The method to confirm the category of surfaces and the plotting methods are discussed in... According to the factors that confirm the shape of surface, it is classified into two categories: arc surface and curve surface The method to confirm the category of surfaces and the plotting methods are discussed in this paper, which provide guidance for parts plotting. 展开更多
关键词 surface plotting arc surface curve surface plotting method
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Experimental Research on Resonance Response Differences of the Rotor System with Sliding and Rolling Bearings
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作者 Chen Anhua, Liao Chuanjun, Li Xuejun(Key Lab of Health Maintenance for Mechanical Equipment of Hunan Province, Hunan Science and Technology University, Xiangtan, Hunan 411201) 《工程科学(英文版)》 2007年第2期161-167,共7页
Most of the research work on bearing-rotor systems usually simplifies the supporting bearing as a spring or damp system, and ignores that the resonance responses involve obvious differences when the same rotor system ... Most of the research work on bearing-rotor systems usually simplifies the supporting bearing as a spring or damp system, and ignores that the resonance responses involve obvious differences when the same rotor system is supported by varying types of bearings. Aiming at the resonance responses of coast down running tests of the rotor system, we employed two different bearings in experiments: One is the fluid film journal bearing, and the other is the rolling element bearing. The experimental results obtained with the above bearings are compared. The resonance test Bode plots and orbit shapes of the rotor shaft are established. Also, summarized under resonance are the dynamic characteristics and regularities of the two types of bearing-rotor systems. The natural frequency and resonance mode of the same rotor system will change thoroughly with the type of supporting bearings. The results are helpful for system modeling, security running, dynamic design, the study of dynamic characteristics, and the fault diagnose of bearing-rotor systems. 展开更多
关键词 rotor RESONANCE RESPONSE bearing Bode PLOT ORBIT shape
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Optical Spectroscopy Methods for Determining Semiconductor Bandgaps
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作者 ZHANG Yong 《发光学报》 北大核心 2025年第7期1271-1282,共12页
Although there are numerous optical spectroscopy techniques and methods that have been used to extract the fundamental bandgap of a semiconductor,most of them belong to one of these three approaches:(1)the excitonic a... Although there are numerous optical spectroscopy techniques and methods that have been used to extract the fundamental bandgap of a semiconductor,most of them belong to one of these three approaches:(1)the excitonic absorption,(2)modulation spectroscopy,and(3)the most widely used Tauc-plot.The excitonic absorption is based on a many-particle theory,which is physically the most correct approach,but requires more stringent crystalline quality and appropriate sample preparation and experimental implementation.The Tauc-plot is based on a single-particle theo⁃ry that neglects the many-electron effects.Modulation spectroscopy analyzes the spectroscopy features in the derivative spectrum,typically,of the reflectance and transmission under an external perturbation.Empirically,the bandgap ener⁃gy derived from the three approaches follow the order of E_(ex)>E_(MS)>E_(TP),where three transition energies are from exci⁃tonic absorption,modulation spectroscopy,and Tauc-plot,respectively.In principle,defining E_(g) as the single-elec⁃tron bandgap,we expect E_(g)>E_(ex),thus,E_(g)>E_(TP).In the literature,E_(TP) is often interpreted as E_(g),which is conceptual⁃ly problematic.However,in many cases,because the excitonic peaks are not readily identifiable,the inconsistency be⁃tween E_(g) and E_(TP) becomes invisible.In this brief review,real world examples are used(1)to illustrate how excitonic absorption features depend sensitively on the sample and measurement conditions;(2)to demonstrate the differences between E_(ex),E_(MS),and E_(TP) when they can be extracted simultaneously for one sample;and(3)to show how the popular⁃ly adopted Tauc-plot could lead to misleading results.Finally,it is pointed out that if the excitonic absorption is not ob⁃servable,the modulation spectroscopy can often yield a more useful and reasonable bandgap than Tauc-plot. 展开更多
关键词 semiconductor material bandgap excitonic absorption modulation spectroscopy Tauc plot
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Optimal integration of forest inventory data and aerial image-based canopy height models for forest stand management
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作者 Ardalan Daryaei Zoran Trailovic +3 位作者 Hormoz Sohrabi Clement Atzberger Eduard Hochbichler Markus Immitzer 《Forest Ecosystems》 2025年第3期443-453,共11页
Accurate,reliable,and regularly updated information is necessary for targeted management of forest stands.This information is usually obtained from sample-based field inventory data.Due to the time-consuming and costl... Accurate,reliable,and regularly updated information is necessary for targeted management of forest stands.This information is usually obtained from sample-based field inventory data.Due to the time-consuming and costly procedure of forest inventory,it is imperative to generate and use the resulting data optimally.Integrating field inventory information with remote sensing data increases the value of field approaches,such as national forest inventories.This study investigated the optimal integration of forest inventory data with aerial image-based canopy height models(CHM)for forest growing stock estimation.For this purpose,fixed-area and angle-count plots from a forest area in Austria were used to assess which type of inventory system is more suitable when the field data is integrated with aerial image analysis.Although a higher correlation was observed between remotely predicted growing stocks and field inventory values for fixed-area plots,the paired t-test results revealed no statistical difference between the two methods.The R2 increased by 0.08 points and the RMSE decreased by 7.7 percentage points(24.8m^(3)·ha^(−1))using fixed-area plots.Since tree height is the most critical variable essential for modeling forest growing stock using aerial images,we also compared the tree heights obtained from CHM to those from the typical field inventory approach.The result shows a high correlation(R^(2)=0.781)between the tree heights extracted from the CHM and those measured in the field.However,the correlation decreased by 0.113 points and the RMSE increased by 4.2 percentage points(1.04m)when the allometrically derived tree heights were analyzed.Moreover,the results of the paired t-test revealed that there is no significant statistical difference between the tree heights extracted from CHM and those measured in the field,but there is a significant statistical difference when the CHM-derived and the allometrically-derived heights were compared.This proved that image-based CHM can obtain more accurate tree height information than field inventory estimations.Overall,the results of this study demonstrated that image-based CHM can be integrated into the forest inventory data at large scales and provide reliable information on forest growing stock.The produced maps reflect the variability of growth conditions and developmental stages of different forest stands.This information is required to characterize the status and changes,e.g.,in forest structure diversity,parameters for volume,and can be used for forest aboveground biomass estimation,which plays an important role in managing and controlling forest resources in mid-term forest management.This is of particular interest to forest managers and forest ecologists. 展开更多
关键词 Forest inventory Growing stock Fixed-area plot Angle-count plot Aerial imagery Tree height Random forest regression
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A Timeline-Based Analysis for the Foreshadowing in the Story of Your Name(2016)
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作者 Chang Yen-Jung Hsu Shih-Ya 《Journalism and Mass Communication》 2025年第4期224-235,共12页
Animation has been a popular form of feature length movie.In addition to the mean of entertainment,some animated works move audiences deeply and even arouse their reflection.In order to achieve this,the setup of story... Animation has been a popular form of feature length movie.In addition to the mean of entertainment,some animated works move audiences deeply and even arouse their reflection.In order to achieve this,the setup of story structure is critical,and the arrangement of the time and setting of foreshadowing in plots influence significantly on audiences’understanding and feeling towards films.Your Name,directed by Japanese animation director,Makoto Shinkai,was an animated feature film released in 2016,soon received high praise by audiences and film review critics,and ended with the highest gross in box office of the director’s works ever.The story of this animation is special for its non-linear structure,which is seldom seen in feature length animated works.The question on how this non-linear structure presents a compelling story and touch audiences so deeply is worth to explore in depth.There is very few analytical study that dedicates on the examination of the foreshadowing based on timeline from an empirical point of view in the area of narrative studies.Hence,this study investigates the spatial-time arrangement,and foreshadowing of plots in Your Name with the basis of timeline in the film.The textual analysis is undertaken with timeline by deconstructing events and elements in the story to look into the arrangement of foreshadowing.The result indicates that the spatial-time structure is complicated by keeps jumping between the year 2013 and 2016 from the two main characters’point of views in different locations,and ends in the year 2021.There are six elements of foreshadowing in this story,and each of them corresponds to important turning points of the story.They appear in the first and the second act of the story to progress the storyline and make the story reasonable through the functions of advanced notice and advanced mention,and gradually echo and accumulate to build up the climax of the narrative to cross over to the third act.In spite of the three settings of the story,the crash of meteorite,the exchanging of body and soul,and the time traveling are rather ordinary,elements of foreshadowing originated form Japanese folk culture interweave plots of the story to create its specialty. 展开更多
关键词 Your Name NARRATIVE TIMELINE PLOTS FORESHADOWING
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