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Detailed Statistic Analysis Method of Split-split Plot Design in Agricultural Research
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作者 李必富 《Agricultural Science & Technology》 CAS 2017年第7期1164-1167,1172,共5页
Based on a practical research test, the statistic analysis method for the experimental data in the split-split plot design was introduced in detail, especially in- troduced the significant test method of three-factor ... Based on a practical research test, the statistic analysis method for the experimental data in the split-split plot design was introduced in detail, especially in- troduced the significant test method of three-factor interaction and the calculation of test value, which solved the problem of how to make statistical analysis on the data in split-split plot design. 展开更多
关键词 Split-split plot design Variance analysis Three-factor interaction
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Spatial and temporal analysis of beta diversity in the Barro Colorado Island forest dynamics plot, Panama 被引量:7
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作者 Pierre Legendre Richard Condit 《Forest Ecosystems》 SCIE CSCD 2019年第1期76-86,共11页
Background: Ecologists are interested in assessing the spatial and temporal variation in ecological surveys repeated over time. This paper compares the 1985 and 2015 surveys of the Barro Colorado Forest Dynamics plot(... Background: Ecologists are interested in assessing the spatial and temporal variation in ecological surveys repeated over time. This paper compares the 1985 and 2015 surveys of the Barro Colorado Forest Dynamics plot(BCI), Panama,divided into 1250(20 m × 20 m) quadrats.Methods, spatial analysis: Total beta diversity was measured as the total variance of the Hellinger-transformed community data throughout the BCI plot. Total beta was partitioned into contributions of individual sites(LCBD indices), which were tested for significance and mapped.Results, spatial analysis: LCBD indices indicated the sites with exceptional community composition. In 1985,they were mostly found in the swamp habitat. In the 2015 survey, none of the swamp quadrats had significant LCBDs.What happened to the tree community in the interval?Methods, temporal analysis: The dissimilarity in community composition in each quadrat was measured between time 1(1985) and time 2(2015). Temporal Beta Indices(TBI) were computed from abundance and presence-absence data and tested for significance. TBI indices can be decomposed into B = species(or abundances-per-species) losses and C = species(or abundances-per-species) gains. B-C plots were produced; they display visually the relative importance of the loss and gain components, through time, across the sites.Results, temporal analysis: In BCI, quadrats with significant TBI indices were found in the swamp area, which is shrinking in importance due to changes to the local climate. A published habitat classification divided the BCI forest plot into six habitat zones. Graphs of the B and C components were produced for each habitat group. Group 4(the swamp) was dominated by species(and abundances-per-species) gains whereas the five other habitat groups were dominated by losses, some groups more than others.Conclusions: We identified the species that had changed the most in abundances in the swamp between T1 and T2.This analysis supported the hypothesis that the swamp is drying out and is invaded by species from the surrounding area. Analysis of the B and C components of temporal beta diversity bring us to the heart of the mechanisms of community change through time: losses(B) and gains(C) of species, losses and gains of individuals of various species. TBI analysis is especially interesting in species-rich communities where we cannot examine the changes in every species individually. 展开更多
关键词 BETA DIVERSITY B-C plotS BCI forest dynamics plot Space-time analysis Temporal BETA DIVERSITY
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Derringer desirability and kinetic plot LC-column comparison approach for MS-compatible lipopeptide analysis 被引量:1
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作者 Matthias D’Hondt Frederick Verbeke +3 位作者 Sofie Stalmans Bert Gevaert Evelien Wynendaele Bart De Spiegeleer 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第3期173-182,共10页
Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antit... Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antitumor, immune-modulating and cell-penetrating compounds. However, due to their specific structure, chromatographic analysis often requires special buffer systems or the use of trifluoroacetic acid, limiting mass spectrometry detection. Therefore, we used a traditional aqueous/acetonitrile based gradient system, containing 0.1% (m/v) formic acid, to separate four pharmaceutically relevant lipopeptides (polymyxin B1, caspofungin, daptomycin and gramicidin A1), which were selected based upon hierarchical cluster analysis (HCA) and principal component analysis (PCA).In total, the performance of four different C18 columns, including one UPLC column, were evaluated using two parallel approaches. First, a Derringer desirability function was used, whereby six single and multiple chromatographic response values were rescaled into one overall D-value per column. Using this approach, the YMC Pack Pro C18 column was ranked as the best column for general MS-compatible lipopeptide separation. Secondly, the kinetic plot approach was used to compare the different columns at different flow rate ranges. As the optimal kinetic column performance is obtained at its maximal pressure, the length elongation factor λ(Pmax/Pexp) was used to transform the obtained experimental data (retention times and peak capacities) and construct kinetic performance limit (KPL) curves, allowing a direct visual and unbiased comparison of the selected columns, whereby the YMC Triart C18 UPLC and ACE C18 columns performed as best. Finally, differences in column performance and the (dis)advantages of both approaches are discussed. 展开更多
关键词 LIPOPEPTIDE Hierarchical cluster analysis (HCA) Principal component analysis (PCA) LC-MS Kinetic plot Derringer desirability function
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Application of SWAT99.2 to sensitivity analysis of water balance components in unique plots in a hilly region
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作者 Jun-feng Dai Jia-zhou Chen +3 位作者 Guo-an Lu Larry C. Brown Lei Gan Qin-xue Xu 《Water Science and Engineering》 EI CAS CSCD 2017年第3期209-216,共8页
Although many sensitivity analyses using the soil and water assessment tool(SWAT) in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. I... Although many sensitivity analyses using the soil and water assessment tool(SWAT) in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. In addition, sensitivity analysis of percolation and evapotranspiration with SWAT has seldom been undertaken. In this study, SWAT99.2 was calibrated to simulate water balance components for unique plots in Southern China from 2000 to 2001, which included surface runoff, percolation, and evapotranspiration. Twenty-one parameters classified into four categories, including meteorological conditions, topographical characteristics, soil properties, and vegetation attributes, were used for sensitivity analysis through one-at-a-time(OAT) sampling to identify the factor that contributed most to the variance in water balance components. The results were shown to be different for different plots, with parameter sensitivity indices and ranks varying for different water balance components. Water balance components in the broad-leaved forest and natural grass plots were most sensitive to meteorological conditions, less sensitive to vegetation attributes and soil properties, and least sensitive to topographical characteristics. Compared to those in the natural grass plot, water balance components in the broad-leaved forest plot demonstrated higher sensitivity to the maximum stomatal conductance(GSI) and maximum leaf area index(BLAI). 展开更多
关键词 Forest and GRASS plotS WATER balance Sensitivity analysis Soil and WATER assessment tool (SWAT) One-at-a-time (OAT) method
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Establishment of Permanent Sample Plots and Analysis of Stand Characteristics for Interior Douglas-Fir Forests
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作者 宫伟光 PeterL.Marshall 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第1期23-26,共4页
In order to study the dynamics of uneven-aged stands of interior Douglas-fir, Pseudotsuga menzesii var.glouca (Mirb.) Franco in future, six permanent sample plots wer set up on the Knife Creek Block of the Alex Fraser... In order to study the dynamics of uneven-aged stands of interior Douglas-fir, Pseudotsuga menzesii var.glouca (Mirb.) Franco in future, six permanent sample plots wer set up on the Knife Creek Block of the Alex Fraser Researh Forcst of University of British Columbia. The measurements and observations for all living trees within theboundaries of a plot wer madc, including DBH(diameter at breast height), TTH(total tree height), height to lowest livingbranch, crown diameter, tree vigor, angle of lean, distance of lean, direction of lean and tree location. Based on the data,some stand characteristics of the plots were analyzed simply and preliminarily. Results showed that most of the interiortrees on the plots are ranged 10-20 cm in distribution of DBH class, and 2-6 m in distribution of rm class. Trees withdifferent fors, however, are distributed unevenly. The relationship between total tree height and diameter at breast heightfollows a quadratic distribution, Y=a+bX+cX2. 展开更多
关键词 Permanent sample plot Stand analysis DOUGLAS-FIR
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A Reinterpretation of Historic Aquifer Tests of Two Hydraulically Fractured Wells by Application of Inverse Analysis, Derivative Analysis, and Diagnostic Plots
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作者 Patrick A. Hammond Malcolm S. Field 《Journal of Water Resource and Protection》 2014年第5期481-506,共26页
Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of t... Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of the data to enhance the knowledge and the predictive capabilities of the flow system. This work thoroughly reanalyzes a series of pre- and post-hydraulic fracturing, single-well aquifer tests conducted in two crystalline rock wells in New Hampshire as part of an early 1970’s study. Previous analyses of the data had relied on older manual type-curve methods for predicting the possible effects of hydraulic fracturing. This work applies inverse analysis, derivative analysis, and diagnostic plots to reanalyze the 1970’s aquifer test data. Our results demonstrate that the aquifer tests were affected by changes in flow regimes, dewatering of the aquifer and discrete fractures, and changes due to well development. Increases in transmissivities are related to well development prior to hydraulic fracturing, propagation of a single, vertical fracture hydraulically connecting the two wells after stimulation and expansion of troughs of depression. After hydraulic fracturing, the estimated total yield of the individual wells increased by 2.5 times due to the hydraulic fracturing. However, the wells may be receiving water from the same source, and well interference may affect any significant increase in their combined yield. Our analyses demonstrate the value in applying inverse analysis, derivative analysis, and diagnostic plots over the conventional method of manual type-curve analysis. In addition, our improvement in the aquifer test interpretation of the 1970’s test data has implications for more reliable estimates of sustained well yields. 展开更多
关键词 Aquifer-Test analysis Inverse analysis Derivative analysis DIAGNOSTIC plotS Hydraulic FRACTURING
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Analysis of Key Features of Non-Linear Behavior Using Recurrence Plots. Case Study: Urban Pollution at Mexico City
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作者 Marco A. Aceves-Fernandez Jesus Carlos Pedraza-Ortega +3 位作者 Artemio Sotomayor-Olmedo Juan M. Ramos-Arreguín Jose Emilio Vargas-Soto Saul Tovar-Arriaga 《Journal of Environmental Protection》 2012年第9期1147-1160,共14页
The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw da... The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using Recurrence Analysis for pollution monitoring and control. 展开更多
关键词 RECURRENCE plot AIR Quality AIR POLLUTION Modelling ATMOSPHERIC POLLUTION RECURRENCE Quantification analysis
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Plot Analysis of The Importance of Being Ernest
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作者 郑艳红 《科教导刊》 2013年第29期181-182,共2页
Throughout Oscar Wilde’s farcical comedy,The Importance of Being Ernest,there are two story lines.The lines are both independent to each other,but are connected with each other.With the author’s thoughtful arrangeme... Throughout Oscar Wilde’s farcical comedy,The Importance of Being Ernest,there are two story lines.The lines are both independent to each other,but are connected with each other.With the author’s thoughtful arrangement and distinctive technology,the two lines push the development of plot;intensify the depth of conflict and make the structure complete.It seems the author told us a story,but indeed it gives us a lot of inspiration and education. 展开更多
关键词 plot analysis double-line structure CONFLICT arrangement
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A linear analysis of the space structure of the standard plot in city
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作者 Yang Qingyuan,female,32 years old,associate professor. Yang Qingyuan Department of Urban Science,Environment and Resources,Southwest China Normal University,Chongqing 400715 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第5期107-115,共9页
City’sstandardplotsaresomelandblockssetupinaregion,whichlandquality,individualfactors,landusebenefitandprice... City’sstandardplotsaresomelandblockssetupinaregion,whichlandquality,individualfactors,landusebenefitandpricearerepresentat... 展开更多
关键词 STANDARD plot SPACE DISPOSITION LINEAR analysis road network
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A new process monitoring method based on noisy time structure independent component analysis 被引量:2
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作者 蔡连芳 田学民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期162-172,共11页
Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the advers... Conventional process monitoring method based on fast independent component analysis(Fast ICA) cannot take the ubiquitous measurement noises into account and may exhibit degraded monitoring performance under the adverse effects of the measurement noises. In this paper, a new process monitoring approach based on noisy time structure ICA(Noisy TSICA) is proposed to solve such problem. A Noisy TSICA algorithm which can consider the measurement noises explicitly is firstly developed to estimate the mixing matrix and extract the independent components(ICs). Subsequently, a monitoring statistic is built to detect process faults on the basis of the recursive kurtosis estimations of the dominant ICs. Lastly, a contribution plot for the monitoring statistic is constructed to identify the fault variables based on the sensitivity analysis. Simulation studies on the continuous stirred tank reactor system demonstrate that the proposed Noisy TSICA-based monitoring method outperforms the conventional Fast ICA-based monitoring method. 展开更多
关键词 Process monitoring Independent component analysis Measurement noises KURTOSIS Mixing matrix Contribution plot Sensitivity analysis
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Chemical composition and Mott-Schottky analysis of passive film formed on G3 alloy in bicarbonate/carbonate buffer solution 被引量:1
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作者 Dangguo LI Darong CHEN Jiadao WANG Haosheng CHEN 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2010年第6期461-472,共12页
The chemical composition and semi-conductive properties of passive film on nickel- based alloy (G3 alloy) in bicarbonate/carbonate buffer solution were investigated by Auger electron spectroscopy (AES), X-ray phot... The chemical composition and semi-conductive properties of passive film on nickel- based alloy (G3 alloy) in bicarbonate/carbonate buffer solution were investigated by Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), elec- trochemical impedance spectra (EIS) and Mott-Schottky plot. AES and XPS results showed that the passive film appeared double-layer structure, in which the inner film was composed of nickel oxide, the mixed nickel-chromium-molybdenum-manganese oxides were the major component of the outer film. The electrochemical results revealed that the factors including frequency, potential, time, temperature and pH value can affect the semi-conductive property, the doping densities decreased with increasing potential and pH value, prolonging time and decreasing temperature. According to the above results, it can be concluded that the film protection on the substrate was enhanced with increasing potential and pH value, prolonging time and decreasing temperature. 展开更多
关键词 Nickel-based alloy Auger electron analysis (AES) X-ray photo- electron spectroscopy (XPS) Electrochemical impedance spectra (EIS) Mott-Schottky plot
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Effects of Hyperventilation on Venous-Arterial Bicarbonate Concentration Difference: A Possible Pitfall in Venous Blood Gas Analysis 被引量:1
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作者 Akira Umeda Kazuteru Kawasaki +2 位作者 Tadashi Abe Tateki Yamane Yasumasa Okada 《International Journal of Clinical Medicine》 2014年第2期76-80,共5页
Objectives: Recent reports on venous blood gas analysis have shown that venous bicarbonate concentration is useful in the evaluation of the body acid-base status. Most of these reports have been based on the Bland-Alt... Objectives: Recent reports on venous blood gas analysis have shown that venous bicarbonate concentration is useful in the evaluation of the body acid-base status. Most of these reports have been based on the Bland-Altman analysis comparing arterial and venous blood gas values. We intended to elucidate any factors that decrease the agreement between venous and arterial bicarbonate concentrations, which might impair the usefulness of venous blood gas analysis. Methods: Healthy volunteers and patients with various diseases (n = 141) were evaluated by simultaneous arterial and venous blood sampling and Bland-Altman analysis. The venous-arterial bicarbonate concentration difference was compared between healthy volunteers and untreated respiratory alkalosis patients. Intentional hyperventilation (30 or 60 breaths/min, for 3 min) was also performed on 6 healthy volunteers and the venous-arterial bicarbonate concentration difference was evaluated. Results: The relative average bias in bicarbonate concentration was 2.00 mEq/l with venous bicarbonate higher than arterial bicarbonate with 95% limits of agreement of ±4.15 mEq/l. Hyperventilation challenges increased the venous-arterial bicarbonate concentration difference in an intensity-dependent manner. The venous-arterial bicarbonate concentration difference was higher in untreated respiratory alkalosis patients than in healthy volunteers (P Conclusion: Although venous bicarbonate may be useful to evaluate the body acid-base status, hyperventilation increases the venous-arterial bicarbonate concentration difference. Physicians should keep this phenomenon in mind. 展开更多
关键词 HYPERVENTILATION BICARBONATE bland-altman analysis VENOUS Blood Gas analysis
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Post-Hoc Comparison in Survival Analysis: An Easy Approach
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作者 Arunabh Tripathi Anant Pandey 《Journal of Biosciences and Medicines》 2017年第3期112-119,共8页
Survival studies mainly deal with distribution of time to event. Often in such studies researchers are interested in comparing several treatment or prognostic groups. At the time of analysis, there is an unmeasured ch... Survival studies mainly deal with distribution of time to event. Often in such studies researchers are interested in comparing several treatment or prognostic groups. At the time of analysis, there is an unmeasured chance of making type I error, or finding a falsely significant difference between any two groups. The chance of making type I error is increased, if multiple groups are compared simultaneously. In this paper, survival analysis with Bonferroni correction is explained in easy way to cope up with this issue. The DLHS-3 data are taken to explain this methodology in the context of neonatal survival. Kaplan-meier plot with three survival comparison test is used to elaborate the application of Bonferroni correction. 展开更多
关键词 SURVIVAL analysis Bonferroni CORRECTION Kaplan-Meier plot
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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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Parameter Sensitivity and Qualitative Analysis of Dynamics of Ovarian Tumor Growth Model with Treatment Strategy
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作者 Md. Shah Alam Md. Kamrujjaman Md. Shafiqul Islam 《Journal of Applied Mathematics and Physics》 2020年第6期941-955,共15页
In this paper, we are interested to find the most sensitive parameter, local and global stability of ovarian tumor growth model. For sensitivity analysis, we use Latin Hypercube Sampling (LHS) method to generate sampl... In this paper, we are interested to find the most sensitive parameter, local and global stability of ovarian tumor growth model. For sensitivity analysis, we use Latin Hypercube Sampling (LHS) method to generate sample points and Partial Rank Correlation Coefficient (PRCC) method, uses those sample points to find out which parameters are important for the model. Based on our findings, we suggest some treatment strategies. We investigate the sensitivity of the parameters for tumor volume, <em>y</em>, cell nutrient density, <em>Q</em> and maximum tumor size, <em>ymax</em>. We also use Scatter Plot method using LHS samples to show the consistency of the results obtained by using PRCC. Moreover, we discuss the qualitative analysis of ovarian tumor growth model investigating the local and global stability. 展开更多
关键词 Parameter Sensitivity Latin Hypercube Sampling Partial Rank Correlation Coefficient Scatter plot MONOTONICITY Stability analysis
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Early Building Design:Informed decision-making by exploring multidimensional design space using sensitivity analysis 被引量:1
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作者 Torben Φstergrd Rasmus L.Jensen +1 位作者 Steffen E.Maagaard 侯恩哲 《建筑节能》 CAS 2017年第5期75-75,共1页
This paper describes a novel approach to explore a multidimensional design space and guide multi-actor decision making in the design of sustainable buildings.The aim is to provide proactive and holistic guidance of th... This paper describes a novel approach to explore a multidimensional design space and guide multi-actor decision making in the design of sustainable buildings.The aim is to provide proactive and holistic guidance of the design team.We propose to perform exhaustive Monte Carlo simulations in an iterative design approach that consists of tw o steps:1) preparation by the modeler,and 2) a multi-collaborator meeting.In the preparation phase,the simulation modeler performs Morris sensitivity analysis to fixate insignificant model inputs and to identify non-linearity and interaction effects.Next,a representation of the global design space is obtained from thousands of simulations using low-discrepancysequences(LPτ) for sampling.From these simulations,the modeler constructs fast metamodels and performs quantitative sensitivity analysis.During the meeting,the design team explores the global design space by filtering the thousands of simulations.Variable filter criteria are easily applied using an interactive parallel coordinate plot w hich provide immediate feedback on requirements and design choices.Sensitivity measures and metamodels show the combined effects of changing a single input and how to remedy unw anted output changes.The proposed methodology has been developed and tested through real building cases using a normative model to assess energy demand,thermal comfort,and daylight. 展开更多
关键词 comfort HOLISTIC iterative interactive PROACTIVE sustainable COORDINATE REMEDY STEPS EXPLORING
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小区玉米籽粒联合收获机的设计与试验
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作者 王彬 董学虎 +1 位作者 张培 陈兴洲 《农机化研究》 北大核心 2026年第1期48-55,共8页
为了改善国内小区玉米育种收获机械装备缺乏、收获过程过于依靠人工的现状,设计了一种自走式小区玉米籽粒联合收获机。该机采用摘穗板-拉茎辊式摘穗、剥皮脱粒装置柔性脱粒,实现了一次性完成摘穗-剥皮-脱粒的作业要求。使用Design-Exper... 为了改善国内小区玉米育种收获机械装备缺乏、收获过程过于依靠人工的现状,设计了一种自走式小区玉米籽粒联合收获机。该机采用摘穗板-拉茎辊式摘穗、剥皮脱粒装置柔性脱粒,实现了一次性完成摘穗-剥皮-脱粒的作业要求。使用Design-Expert软件建立了因素与指标的响应面数学模型,分析了各因素与评价指标之间的关系并对影响因素进行优化。试验结果表明,各因素对果穗损失率影响的显著性顺序:摘穗台高度>前进速度>脱粒辊转速;各因素对籽粒破损率影响的显著性顺序:脱粒辊转速>前进速度>摘穗台高度;各因素对作业生产率影响的显著性顺序:前进速度>脱粒辊转速>摘穗台高度。各试验因素最优参数组合为机具前进速度2.12 m/s、摘穗台高度40 cm、脱粒辊转速700 r/min,此时果穗损伤率为0.26%、籽粒破损率为1.06%、作业生产率为0.20 hm^(2)/h。验证试验结果表明,果穗损伤率和籽粒破损率的实测值相对于预测值误差分别为0.08%和0.15%,预测模型可靠。研究结果可为玉米籽粒的机械化收获提供依据。 展开更多
关键词 小区育种 玉米收获 柔性脱粒 回归分析
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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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A Plot Story:The Ransom of Red Chief
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作者 王思宇 《海外英语》 2015年第2期187-188,共2页
The Ransom of Red Chief is a short story written by O·Henry. Some critics regard it as a plot story but some do not. A typical plot story should focus on the plot :using techniques such as flashback or foreshadow... The Ransom of Red Chief is a short story written by O·Henry. Some critics regard it as a plot story but some do not. A typical plot story should focus on the plot :using techniques such as flashback or foreshadowing to unfold the plot and containing exposition, complication, climax, resolution, conclusion to rich the plot. The main characters are presented with internal and external conflicts as well. In this thesis, a detailed analysis will be presented to prove that this story is really a plot story. 展开更多
关键词 The RANSOM of RED CHIEF analysis a plot STORY
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Box-plot-SA-BP:变压器DGA多参量故障诊断模型 被引量:1
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作者 周威振 赵银山 +1 位作者 王兴 张鹏望 《电力大数据》 2023年第5期44-52,共9页
油中溶解气体分析(DGA)方法是一种典型的充油电力设备故障诊断方法,广泛应用于电力变压器故障检测与状态评估,但由于样本数据的可靠性和诊断模型的有效性影响,导致DGA诊断方法准确率较低。文中提出了一种Box-plot-SA-BP模型,首先,采用Bo... 油中溶解气体分析(DGA)方法是一种典型的充油电力设备故障诊断方法,广泛应用于电力变压器故障检测与状态评估,但由于样本数据的可靠性和诊断模型的有效性影响,导致DGA诊断方法准确率较低。文中提出了一种Box-plot-SA-BP模型,首先,采用Box-plot数据检测法去除异常数据以解决数据质量的问题,然后,利用自注意力机制(Self-attention, SA)准确捕捉多参量样本数据间的联系,提取更加稳定可靠的特征,最后设计BP网络多分类模型实现变压器故障诊断。对比实验证明了Box-plot-SA-BP模型的良好性能,具有较高的应用价值。 展开更多
关键词 油中溶解气体分析 箱线图 自注意力机制 BP神经网络 变压器故障诊断
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