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The prediction of projectile-target intersection for moving tank based on adaptive robust constraint-following control and interval uncertainty analysis
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作者 Cong Li Xiuye Wang +2 位作者 Yuze Ma Fengjie Xu Guolai Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期351-363,共13页
To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method... To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method proposed provides a novel way to predict the impact point of projectile for moving tank.First,bidirectional stability constraints and stability constraint-following error are constructed using the Udwadia-Kalaba theory,and an adaptive robust constraint-following controller is designed considering uncertainties.Second,the exterior ballistic ordinary differential equation with uncertainties is integrated into the controller,and the pointing control of stability system is extended to the impact-point control of projectile.Third,based on the interval uncertainty analysis method combining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is proposed.Finally,the co-simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of control system.The results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit probability.The adaptive robust constraint-following control can effectively restrain the uncertainties caused by road excitation and model error. 展开更多
关键词 Tank stability control Constraint-following Adaptive robust control uncertainty analysis Prediction of projectile-target intersection
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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 Mixed uncertainty probability model convex model time-variant reliability analysis
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Uncertainty and sensitivity analysis of in-vessel phenomena under severe accident mitigation strategy based on ISAA-SAUP program
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作者 Hao Yang Ji-Shen Li +2 位作者 Zhi-Ran Zhang Bin Zhang Jian-Qiang Shan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期108-123,共16页
The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce... The phenomenology involved in severe accidents in nuclear reactors is highly complex.Currently,integrated analysis programs used for severe accident analysis heavily rely on custom empirical parameters,which introduce considerable uncertainty.Therefore,in recent years,the field of severe accidents has shifted its focus toward applying uncertainty analysis methods to quantify uncertainty in safety assessment programs,known as“best estimate plus uncertainty(BEPU).”This approach aids in enhancing our comprehension of these programs and their further development and improvement.This study concentrates on a third-generation pressurized water reactor equipped with advanced active and passive mitigation strategies.Through an Integrated Severe Accident Analysis Program(ISAA),numerical modeling and uncertainty analysis were conducted on severe accidents resulting from large break loss of coolant accidents.Seventeen uncertainty parameters of the ISAA program were meticulously screened.Using Wilks'formula,the developed uncertainty program code,SAUP,was employed to carry out Latin hypercube sampling,while ISAA was employed to execute batch calculations.Statistical analysis was then conducted on two figures of merit,namely hydrogen generation and the release of fission products within the pressure vessel.Uncertainty calculations revealed that hydrogen production and the fraction of fission product released exhibited a normal distribution,ranging from 182.784 to 330.664 kg and from 15.6 to 84.3%,respectively.The ratio of hydrogen production to reactor thermal power fell within the range of 0.0578–0.105.A sensitivity analysis was performed for uncertain input parameters,revealing significant correlations between the failure temperature of the cladding oxide layer,maximum melt flow rate,size of the particulate debris,and porosity of the debris with both hydrogen generation and the release of fission products. 展开更多
关键词 Gen-III PWR Severe accident mitigation Wilks’formula HYDROGEN Fission products uncertainty and sensitivity analysis
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Application of Choquet Integral-Importance-Performance Analysis and TOPSIS Methods in Approaching the Preference Factors of Calligraphy and Seal Engraving Imagery
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作者 Yu Hsuan Chang Jiann Sheng Jiang Min Min Lin 《Journal of Contemporary Educational Research》 2024年第5期276-288,共13页
Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Call... Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Calligraphy and seal engraving,as two closely related systems in traditional Chinese art,have developed through the ages.Due to changes in lifestyle and advancements in modern technology,their original functions of daily writing and verification have gradually diminished.Instead,they have increasingly played a significant role in commercial art.This study utilizes the Evaluation Grid Method(EGM)and the Analytic Hierarchy Process(AHP)to research the key preference factors in the application of calligraphy and seal engraving imagery.Different from the traditional 5-point equal interval semantic questionnaire,this study employs a non-equal interval semantic questionnaire with a golden ratio scale,distinguishing the importance ratio of adjacent semantic meanings and highlighting the weighted emphasis on visual aesthetics.Additionally,the study uses Importance-Performance Analysis(IPA)and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)to obtain the key preference sequence of calligraphy and seal engraving culture.Plus,the Choquet integral comprehensive evaluation is used as a reference for IPA comparison.It is hoped that this study can provide cultural imagery references and research methods,injecting further creativity into industrial design. 展开更多
关键词 evaluation Grid Method Analytic Hierarchy Process CALLIGRAPHY Seal engraving Importance-Performance analysis Choquet integral TOPSIS
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The Application and Effect Evaluation of Corpus Linguistics in English Teaching
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作者 Lei Yang 《Journal of Contemporary Educational Research》 2024年第7期290-296,共7页
This paper explores the application and effect evaluation of corpus linguistics in English teaching.It first introduces the basic concepts and development history of corpus linguistics,then analyzes its connection wit... This paper explores the application and effect evaluation of corpus linguistics in English teaching.It first introduces the basic concepts and development history of corpus linguistics,then analyzes its connection with language teaching theories,discussing the advantages and challenges of using corpora in language teaching.Next,it delves into the methods and technologies for building and utilizing corpora,as well as their role in developing teaching resources.Lastly,within the framework and methods of teaching effect evaluation,specific application cases of corpus linguistics in teaching design are analyzed,and their effects are assessed.Recommendations for teaching improvement and future development directions are also proposed. 展开更多
关键词 Corpus linguistics English teaching Teaching resource development Corpus language analysis Effect evaluation Teaching improvement
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Evaluation of Energy Efficiency and Analysis of Influencing Factors of Company CW’s Manufacturing Workshops
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作者 Pengju Zhang 《Journal of Electronic Research and Application》 2024年第2期18-26,共9页
In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 1... In this work,the Slacks-Based Measure(SBM)model within Data Envelopment Analysis was employed to establish a set of indicators for evaluating the energy efficiency of manufacturing workshops.The energy efficiency of 12 Company CW’s manufacturing workshops from 2016 to 2022 was assessed.The findings indicated that aside from a few workshops operating at the production frontier,the rest exhibit significant fluctuations in energy efficiency and generally low energy efficiency.Subsequently,a combined GRA-Tobit analysis model was introduced to identify factors influencing the energy efficiency of Company CW’s manufacturing workshops.Regression analysis revealed that technological investments,employee quality,workshop production scale,investment in clean energy,and the level of pollution control all significantly impact the energy efficiency of Company CW’s manufacturing workshops.By evaluating the energy efficiency of Company CW’s manufacturing workshops and studying their influencing factors,this research aids company managers in understanding the energy efficiency of the manufacturing process.It optimizes the combination of various production elements,thereby offering effective guidance for improving the energy efficiency issues of the company’s manufacturing workshops,which can contribute to enhancing the corporation’s overall energy efficiency. 展开更多
关键词 Manufacturing workshop energy efficiency Energy efficiency evaluation Data Envelopment analysis(DEA) GRA-Tobit model
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Distribution,risk evaluation,and source analysis of the heavy metals in the sediment deposition of the lower Shichuanhe River,Shaanxi,China
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作者 Chenhui Hou Caixia Feng Shen Liu 《Acta Geochimica》 EI CAS CSCD 2023年第5期832-844,共13页
In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of... In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of the pollution levels of this area, hope to provide guidance on agricultural production activities in this region. The results show that the heavy metal elements in this area are mainly concentrated at the Qinghe River and Shichuanhe River confluences. Furthermore, the element contents are higher than that of the background levels of the continental crust(UCC) and close to the background levels of the soil from Shaanxi Province;the two most enriched elements are Cd and As, with contents of 0.79 and 22.7 mg·kg-1, respectively, and their contents are 3.8 and 1.72 times higher than that of the background values. Herein, the heavy metal pollution assessment methods applied indicated that Cd and As are the two most abundant pollutant elements in the area’s soils. As has a peak geo-accumulation index value of 3, and the pollution level is high, while Cd exhibits high potential ecological risks due to its high toxicity(potential risk index of 143) and an active fraction of more than 64%.In addition, a principal component analysis and hierarchical cluster analysis study showed that there are two sources of the heavy metals in this area. The Zn, As, Ni, Cu, Pb,and Cr are mainly from natural sources, and the Cd likely comes from a discharge of untreated agricultural wastewater in the region. The Cd which poses a high potential risk and mainly results from human activities, needs to be further monitored. 展开更多
关键词 DISTRIBUTION Risk evaluation Source analysis Heavy metals SEDIMENT Ecological risk
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Research Progress and Prospect of Tourism Carbon Emissions and Its Uncertainty Analysis Under the Goal of Low-Carbon Scenic Spots
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作者 Aihong Wang Qiguang Lyu 《Proceedings of Business and Economic Studies》 2023年第2期25-32,共8页
Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of ... Under the dual carbon goal,China Certified Emissions Reductions(CCER)and the national carbon market have become important means of emission reduction and control.The tourism industry is a strategic pillar industry of China’s national economy,and scenic spots are the main sites of tourism activities.Research on carbon emissions in scenic spots is of great significance for the construction of low-carbon scenic spots and the realization of the dual carbon goal.In this paper,the research on carbon emissions in tourism is reviewed,the current research progress is discussed,and further prospects are made.The research on tourism carbon emissions in China has a good foundation and achieved certain results.However,there are few studies on micro-scales such as scenic spots.The statistical data caliber and measurement methods of carbon emissions are not uniform,and there is a general lack of uncertainty analysis.Future research should focus on building a multi-spatial dimension research system,unifying the statistical caliber and measurement methods of carbon emission data,increasing uncertainty analysis,and ensuring the robustness of research results. 展开更多
关键词 Low-carbon scenic spot Carbon emissions uncertainty analysis
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Uncertainty quantification of inverse analysis for geomaterials using probabilistic programming
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作者 Hongbo Zhao Shaojun Li +3 位作者 Xiaoyu Zang Xinyi Liu Lin Zhang Jiaolong Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期895-908,共14页
Uncertainty is an essentially challenging for safe construction and long-term stability of geotechnical engineering.The inverse analysis is commonly utilized to determine the physico-mechanical parameters.However,conv... Uncertainty is an essentially challenging for safe construction and long-term stability of geotechnical engineering.The inverse analysis is commonly utilized to determine the physico-mechanical parameters.However,conventional inverse analysis cannot deal with uncertainty in geotechnical and geological systems.In this study,a framework was developed to evaluate and quantify uncertainty in inverse analysis based on the reduced-order model(ROM)and probabilistic programming.The ROM was utilized to capture the mechanical and deformation properties of surrounding rock mass in geomechanical problems.Probabilistic programming was employed to evaluate uncertainty during construction in geotechnical engineering.A circular tunnel was then used to illustrate the proposed framework using analytical and numerical solution.The results show that the geomechanical parameters and associated uncertainty can be properly obtained and the proposed framework can capture the mechanical behaviors under uncertainty.Then,a slope case was employed to demonstrate the performance of the developed framework.The results prove that the proposed framework provides a scientific,feasible,and effective tool to characterize the properties and physical mechanism of geomaterials under uncertainty in geotechnical engineering problems. 展开更多
关键词 Geological engineering Geotechnical engineering Inverse analysis uncertainty quantification Probabilistic programming
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Generalized nth-Order Perturbation Method Based on Loop Subdivision Surface Boundary Element Method for Three-Dimensional Broadband Structural Acoustic Uncertainty Analysis
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作者 Ruijin Huo Qingxiang Pei +1 位作者 Xiaohui Yuan Yanming Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期2053-2077,共25页
In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Mill... In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Miller method is employed to solve the problem of non-unique solutions that may be encountered in the external acoustic field,and the nth-order discretization formulation of the boundary integral equation is derived.In addition,the computation of loop subdivision surfaces and the subdivision rules are introduced.In order to confirm the effectiveness of the algorithm,the computed results are contrasted and analyzed with the results under Monte Carlo simulations(MCs)through several numerical examples. 展开更多
关键词 Perturbation method loop subdivision surface isogeometric boundary element method uncertainty analysis
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Can We Estimate the Impacts of Fixed Links Using Current Transport Models?Experiences from Concept Evaluations of Fixed Links on E39
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作者 Trude Tørset 《Journal of Traffic and Transportation Engineering》 2024年第2期92-106,共15页
Transport analysis and impact evaluations are important input for decisions about infrastructure projects.The impacts on transport from fjord crossing tunnels or bridges are the foundation for the cost benefit analysi... Transport analysis and impact evaluations are important input for decisions about infrastructure projects.The impacts on transport from fjord crossing tunnels or bridges are the foundation for the cost benefit analysis,and also the basis for estimating the income from toll collection.Based on experiences from concept evaluations of several fixed link projects on E39,and an ongoing overall analysis,we question the results from transport analysis made by the official tools for such analysis:the RTM(regional transport model)which estimates the demand for trips below 10 km,the NTM(national transport model),for trips of 10 km or more,and the freight transport model.Both the NTM and the freight transport model are integrated in the RTM in the net assignment stage.We will demonstrate strengths and weaknesses in the transport models by showing contra intuitive or questionable results using the model as it is.The following questions arose as the initial results from the transport model were presented:Are the transport models able to capture immediate as well as long-term impacts?How would different assumptions about the monetary costs on these projects affect the forecasted demand and the cost benefit analysis?Are there other and wider ranges of impacts,if the analysis covers the total coastal highway as a whole,compared to evaluating impacts of each fixed link project individually?Do we have enough data to include transport effects of wider impacts of the fixed link projects?We had to deal with these questions in the concept evaluations carried out for the various fixed links project and in the current overall evaluation.We would like to suggest improvements in the analysis tools and emphasize requirements for knowledge about impacts of fixed links projects. 展开更多
关键词 Transport models transport analysis evaluation
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Sensitivity analysis and probability modelling of the structural response of a single-layer reticulated dome subjected to an external blast loading
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作者 Shao-bo Qi Guang-yan Huang +1 位作者 Xu-dong Zhi Feng Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第5期152-163,共12页
The structural response of a single-layer reticulated dome to external explosions is shaped by many variables,and the associated uncertainties imply non-deterministic results.Existing deterministic methods for predict... The structural response of a single-layer reticulated dome to external explosions is shaped by many variables,and the associated uncertainties imply non-deterministic results.Existing deterministic methods for predicting the consequences of specific explosions do not account for these uncertainties.Therefore,the impact of the uncertainties associated with these input variables on the structures’response needs to be studied and quantified.In this study,a parametric uncertainty analysis was conducted first.Then,local and global sensitivity analyses were carried out to identify the drivers of the structural dynamic response.A probabilistic structural response model was established based on sensitive variables and a reasonable sample size.Furthermore,some deterministic empirical methods for explosion-resistance design,including the plane blast load model of CONWEP,the curved blast load model under the 50%assurance level,and the 20%mass-increased method,were used for evaluating their reliability.The results of the analyses revealed that the structural response of a single-layer reticulated dome to an external blast loading is lognormally distributed.Evidently,the MB0.5 method based on the curved reflector load model yielded results with a relatively stable assurance rate and reliability,but CONWEP did not;thus,the 1.2MB0.5 method can be used for making high-confidence simple predictions.In addition,the results indicated that the structural response is very sensitive to the explosion parameters.Based on these results,it is suggested that for explosion proofing,setting up a defensive barrier is more effective than structural strengthening. 展开更多
关键词 Dome structure Blast load uncertainty Sensitivity analysis Probabilistic investigation Reliability evaluation
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Rockfill material uncertainty inversion analysis of concrete-faced rockfill dams using stacking ensemble strategy and Jaya optimizer
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作者 Qin Ke Ming-chao Li +1 位作者 Qiu-bing Ren Wen-chao Zhao 《Water Science and Engineering》 EI CAS CSCD 2023年第4期419-428,共10页
Numerical simulation of concrete-faced rockfill dams(CFRDs)considering the spatial variability of rockfill has become a popular research topic in recent years.In order to determine uncertain rockfill properties effici... Numerical simulation of concrete-faced rockfill dams(CFRDs)considering the spatial variability of rockfill has become a popular research topic in recent years.In order to determine uncertain rockfill properties efficiently and reliably,this study developed an uncertainty inversion analysis method for rockfill material parameters using the stacking ensemble strategy and Jaya optimizer.The comprehensive implementation process of the proposed model was described with an illustrative CFRD example.First,the surrogate model method using the stacking ensemble algorithm was used to conduct the Monte Carlo stochastic finite element calculations with reduced computational cost and improved accuracy.Afterwards,the Jaya algorithm was used to inversely calculate the combination of the coefficient of variation of rockfill material parameters.This optimizer obtained higher accuracy and more significant uncertainty reduction than traditional optimizers.Overall,the developed model effectively identified the random parameters of rockfill materials.This study provided scientific references for uncertainty analysis of CFRDs.In addition,the proposed method can be applied to other similar engineering structures. 展开更多
关键词 CFRD uncertainty inversion analysis Stochastic finite element Surrogate model Stacking ensemble Jaya algorithm
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Using radium isotopes to evaluate the uncertainty of submarine groundwater discharge in the northeast and entirety of Daya Bay
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作者 Hequan Gu Feng Zhao +6 位作者 Zhixin Ni Meigui Wu Li Zhao Aicui Dang Dongmei Li Minxia Zhang Qin Hu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期24-31,共8页
Submarine groundwater discharge(SGD),which can be traced using naturally occurring radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the ... Submarine groundwater discharge(SGD),which can be traced using naturally occurring radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the Daya Bay,China.However,uncertainties in assessing SGD fluxes must still be discussed in detail.In this study,we attempted to utilize the Monte Carlo method to evaluate the uncertainties of radium-derived SGD flux in the northeast and entirety of the Daya Bay.The results show that the uncertainties of the SGD estimate in the northeast bay are very sensitive to variations in excess radium inventories as well as radium inputs from bottom sediments,while the uncertainties of the SGD estimate for the entire bay are strongly affected by fluctuations in radium inputs from bottom sediments and radium end-members of SGD.This study will help to distinguish the key factors controlling the accuracy of SGD estimates in similar coastal waters. 展开更多
关键词 submarine groundwater discharge(SGD) radium isotopes Monte-Carlo method Daya Bay uncertainty analysis
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Building color and Psychological Evaluation Based on Superposition Analysis:A case study of Pingguoyuan Street in Beijing City
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作者 CHEN Luming 《Journal of Landscape Research》 2023年第5期13-17,共5页
China’s construction has entered the high-quality development stage,and the building color landscape as the constituent element of the quality of urban artificial landscape has attracted more and more attention.In th... China’s construction has entered the high-quality development stage,and the building color landscape as the constituent element of the quality of urban artificial landscape has attracted more and more attention.In the process of building the building color evaluation system with the appeal of“public participation”,it is necessary to absorb and adopt public opinions,and the color planning practice cannot completely match the public opinions.In this paper,Pingguoyuan Street in Beijing City was taken as an example,and factor grading was constructed based on the relevant principle of“sensitivity grading”by analyzing the coupling relationship between color and urban artificial landscape structure.GIS technology was used to integrate and analyze residents’color sensitivity data obtained by investigation and interview and form the psychological evaluation of residents’color perception of artificial landscape,so as to provide scientific basis for the color planning of Pingguoyuan Street in Beijing City from the perspective of“space justice”. 展开更多
关键词 Color perception Psychological evaluation system Superposition analysis GIS
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Application of Eye Movement Analysis in Landscape Visual Quality Evaluation
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作者 Dewang LIU Xiaoyu HU +1 位作者 Xinhui HE Baoyong LI 《Meteorological and Environmental Research》 CAS 2023年第3期17-24,共8页
The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of exp... The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of experimental psychology,eye movement technology can show great advantages and potential in landscape visual quality evaluation.On the basis of combing and summarizing the relevant literature,based on the explanation of the technical principle of eye movement analysis,the application field,research content,technical methods and other aspects of eye movement analysis were reviewed.The application prospect of eye movement technology in landscape visual quality evaluation was explored to provide theoretical reference for the in-depth evaluation and research of landscape visual quality evaluation theory. 展开更多
关键词 Eye movement analysis Eye movement tracking Landscape visual quality Visual perception evaluation
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Chromatographic fingerprinting and quantitative analysis for the quality evaluation of Xinkeshu tablet 被引量:5
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作者 Pei Wang Lian Li +4 位作者 Hailong Yang Shijuan Cheng Yingzi Zeng Lei Nie Hengchang Zang 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第6期422-430,共9页
A simple, sensitive and accurate method based on high performance liquid chromato- graphy (HPLC) with diode array detector (DAD) was developed and validated for systematic quality evaluation of one type of traditi... A simple, sensitive and accurate method based on high performance liquid chromato- graphy (HPLC) with diode array detector (DAD) was developed and validated for systematic quality evaluation of one type of traditional Chinese medicine preparations named Xinkeshu (XKS) tablet. In this study, the chromatographic fingerprints of XKS tablet were developed first, 23 peaks were selected as the common peaks to evaluate the similarities among different batches of XKS samples, which were manufactured in a long time span of three years. Additionally, simultaneous quantification of six markers in XKS tablet, including Danshensu, Protocatechuic aldehyde, Puerarin, Daidzin, Salvianolic acid B and Daidzein, was performed. The validation results showed that the developed method was specific, accurate, precise and robust. The preliminary explanation on why a close similarity between fingerprints did not exactly mean similar contents of chemical components in samples was given. The contribution of each chromatographic peak to similarity was also evaluated. The developed method offers an efficient, reliable and practical approach for systematic quality evaluation of XKS tablet. 展开更多
关键词 Fingerprint analysis Quality evaluation Multi-ingredient quanti-tative analysis Xinkeshu tablet High-performanceliquid chromatography
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Ecological Safety Evaluation of Land Use in Ji'an City Based on the Principal Component Analysis 被引量:7
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作者 LIU Fei-yue WAN Shao-kai 《Asian Agricultural Research》 2010年第2期49-52,共4页
According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method i... According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method is used to standardize the selected indices,and Principal Component Analysis is applied by using year as a unit.FB is obtained,which is related with the ecological safety of land-use change from 1999 to 2008.According to the scientific,integrative,hierarchical,practical and dynamic principles,ecological safety evaluation index system of land-use change in Ji'an City is established.Principal Component Analysis and evaluation model are used to calculate four parameters,including the natural resources safety index of land use,the socio-economic safety indicators of land use,the eco-environmental safety index of land use,and the ecological safety degree of land use in Ji'an City.Result indicates that the ecological safety degree of land use in Ji'an City shows a slow upward trend as a whole.At the same time,ecological safety degree of land-use change is relatively low in Ji'an City with the safety value of 0.645,which is at a weak safety zone and needs further monitoring and maintenance. 展开更多
关键词 Land use Ecological safety Principal Component analysis evaluation China
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Application of Principal Component Analysis(PCA)to the Evaluation and Screening of Multiactivity Fungi 被引量:4
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作者 YANG Zonglin SHI Yaqi +5 位作者 LI Pinglin PAN Kanghong LI Guoqiang LI Xianguo YAO Shuo ZHANG Dahai 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期763-772,共10页
Continued innovation in screening methodologies remains important for the discovery of high-quality multiactive fungi,which have been of great significance to the development of new drugs.Mangrove-derived fungi,which ... Continued innovation in screening methodologies remains important for the discovery of high-quality multiactive fungi,which have been of great significance to the development of new drugs.Mangrove-derived fungi,which are well recognized as prolific sources of natural products,are worth sustained attention and further study.In this study,118 fungi,which mainly included Aspergillus spp.(34.62%)and Penicillium spp.(15.38%),were isolated from the mangrove ecosystem of the Maowei Sea,and 83.1%of the cultured fungi showed at least one bioactivity in four antibacterial and three antioxidant assays.To accurately evaluate the fungal bioactivities,the fungi with multiple bioactivities were successfully evaluated and screened by principal component analysis(PCA),and this analysis provided a dataset for comparing and selecting multibioactive fungi.Among the 118 mangrove-derived fungi tested in this study,Aspergillus spp.showed the best comprehensive activity.Fungi such as A.clavatonanicus,A.flavipes and A.citrinoterreus,which exhibited high comprehensive bioactivity as determined by the PCA,have great potential in the exploitation of natural products and the development of new drugs.This study demonstrated the first use of PCA as a time-saving,scientific method with a strong ability to evaluate and screen multiactive fungi,which indicated that this method can affect the discovery and development of new drugs. 展开更多
关键词 principal component analysis biological activity FUNGI mangrove ecosystem activity evaluation
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Application of SWAT Model to the Olifants Basin: Calibration, Validation and Uncertainty Analysis 被引量:3
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作者 Charles Gyamfi Julius Musyoka Ndambuki Ramadhan Wanjala Salim 《Journal of Water Resource and Protection》 2016年第3期397-410,共14页
The application of the Soil and Water Assessment Tool (SWAT) to the Olifants Basin in South Africa was the focus of our study with emphasis on calibration, validation and uncertainty analysis. The Basin was discretize... The application of the Soil and Water Assessment Tool (SWAT) to the Olifants Basin in South Africa was the focus of our study with emphasis on calibration, validation and uncertainty analysis. The Basin was discretized into 23 sub-basins and 226 Hydrologic Response Units (HRUs) using 3 arc second (90 m × 90 m) pixel resolution SRTM DEM with stream gauge B7H015 as the Basin outlet. Observed stream flow data at B7H015 were used for model calibration (1988-2001) and validation (2002-2013) using the split sample approach. Relative global sensitivity analysis using SUFI-2 algorithm was used to determine sensitive parameters to stream flow for calibration of the model. Performance efficiency of the Olifants SWAT model was assessed using Nash-Sutcliffe (NSE), coefficient of determination (R<sup>2</sup>), Percent Bias (PBIAS) and Root Mean Square Error-Observation Standard deviation Ratio (RSR). Sensitivity analysis revealed in decreasing order of significance, runoff curve number (CN2), alpha bank factor (ALPHA_BNK), soil evaporation compensation factor (ESCO), soil available water capacity (SOIL_AWC, mm H<sub>2</sub>O/mm soil), groundwater delay (GW_ DELAY, days) and groundwater “revap” coefficient (GW_REVAP) to be the most sensitive parameters to stream flow. Analysis of the model during the calibration period gave the following statistics;NSE = 0.88;R<sup>2</sup> = 0.89;PBIAS = -11.49%;RSR = 0.34. On the other hand, statistics during the validation period were NSE = 0.67;R<sup>2 </sup>= 0.79;PBIAS = -20.69%;RSR = 0.57. The observed statistics indicate the applicability of the SWAT model in simulating the hydrology of the Olifants Basin and therefore can be used as a Decision Support Tool (DST) by water managers and other relevant decisions making bodies to influence policy directions on the management of watershed processes especially water resources. 展开更多
关键词 CALIBRATION VALIDATION uncertainty analysis Olifants Basin SWAT Model
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