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Study on Correlation of Different Methods of Evaluating Degree of Skin Redness
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作者 Jian Yuanqing Ma Lin +3 位作者 Huang Bingting Li Jing Zhang Xiaojie Sun Lili 《China Detergent & Cosmetics》 CAS 2024年第3期50-55,共6页
In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product ... In order to explore the correlation of 3 different methods of evaluating the degree of skin redness,45 healthy Chinese subjects aged 18~45 were recruited to attend a human efficacy evaluation test.An emulsion product which declares soothing and repair efficacy was used each time in the morning and evening for 4 weeks.Three methods,including visual assessment,image analysis and instrument measurement,were taken to test the related indices of skin redness degree respectively.The improvement of skin redness and the correlation of 3 methods were evaluated by comparing the changes of each index before and after using the product.The results show that the face redness degree score and the image analysis a*value significantly reduce at all time points after using the sample(P<0.05),while the instrument probe a*value significantly reduce at the time point after using for 2 weeks(P<0.05).The correlation coefficient of the face redness degree score and the instrument probe a*value is more than 0.33 and less than 0.67,and the significance level is less than 0.01.Therefore,the sample has soothing and repair efficacy for improving skin redness;and the methods of visual assessment and instrument measurement present moderate positive correlation. 展开更多
关键词 SKIN redness COSMETICS efficacy evaluation CORRELATION
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On Evaluating University Teachers’ Morality and Ethics in the New Era
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作者 LIU Qiu-fen 《Journal of Literature and Art Studies》 2024年第1期92-94,共3页
University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the... University teachers play an important role in promoting moral and political education among university students.Regular and long-term construction of teachers’morality and ethics will contribute to the success of the fundamental task of cultivating talents.The present study proposes that due to the multiple identities of university teachers,it is necessary to evaluate the construction of teachers’morality and ethics in terms of what to evaluate and how to evaluate?It is expected that the attempt will provide useful guidance for the construction of university teachers’morality and ethics. 展开更多
关键词 university teachers morality and ethics construction evaluATION
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Method for Evaluating Bolt Competitive Failure Life Under Composite Excitation 被引量:1
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作者 Guangwu Yang Long Yang +3 位作者 Han Zhao Haoxu Ding Bing Yang Shoune Xiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期372-384,共13页
In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode predict... In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite excitation.Based on the competitive failure mechanism,the mode prediction model and“load ratio-life prediction curve”(ξ-N curve)of the bolt competitive failure are established.Given the poor correlation of theξ-N curve,an evaluation model of the bolt competitive failure life is proposed based on Miner’s linear damage accumulation theory.Based on the force analysis of the thread surface and simulation of the bolt connection under composite excitation,a theoretical equation of the bolt competitive failure life is established to validate the model for evaluating the bolt competitive failure life.The results reveal that the proposed model can accurately predict the competitive failure life of bolts under composite excitation,and thereby,it can provide guidance to engineering applications. 展开更多
关键词 BOLT Competitive failure life evaluation model Mode prediction model Composite excitation
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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat 被引量:1
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作者 Zhikai Cheng Xiaobo Gu +5 位作者 Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1523-1540,共18页
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m... In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching. 展开更多
关键词 mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle
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Landslide hazard susceptibility evaluation based on SBAS-InSAR technology and SSA-BP neural network algorithm:A case study of Baihetan Reservoir Area 被引量:1
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作者 GUO Junqi XI Wenfei +4 位作者 YANG Zhiquan SHI Zhengtao HUANG Guangcai YANG Zhengrong YANG Dongqing 《Journal of Mountain Science》 SCIE CSCD 2024年第3期952-972,共21页
Landslide hazard susceptibility evaluation takes on critical significance in early warning and disaster prevention and reduction.In order to solve the problems of poor effectiveness of landslide data and complex calcu... Landslide hazard susceptibility evaluation takes on critical significance in early warning and disaster prevention and reduction.In order to solve the problems of poor effectiveness of landslide data and complex calculation of weights for multiple evaluation factors in the existing landslide susceptibility evaluation models,in this study,a method of landslide hazard susceptibility evaluation is proposed by combining SBAS-InSAR(Small Baseline Subsets-Interferometric Synthetic Aperture Radar)and SSA-BP(Sparrow Search Algorithm-Back Propagation)neural network algorithm.The SBAS-InSAR technology is adopted to identify potential landslide hazards in the study area,update the cataloging data of landslide hazards,and 11 evaluation factors are chosen for constructing the SSA-BP model for training and validation.Baihetan Reservoir area is selected as a case study for validation.As indicated by the results,the application of SBAS-InSAR technology,combined with both ascending and descending orbit data,effectively addresses the incomplete identification of landslide hazards caused by geometric distortion of single orbit SAR data(e.g.,shadow,overlay,and perspective contraction)in deep canyon areas,thereby enabling the acquisition of up-to-date landslide hazard data.Moreover,in comparison to the conventional BP(Back Propagation)algorithm,the accuracy of the model constructed by the SSA-BP algorithm exhibits a significant increase,with mean squared error and mean absolute error reduced by 0.0142 and 0.0607,respectively.Additionally,during the process of susceptibility evaluation,the SSA-BP model effectively circumvents the issue of considerable manual interventions in calculating the weight of evaluation factors.The area under the curve of this model reaches 0.909,surpassing BP(0.835),random forest(0.792),and the information value method(0.699).The risk of landslide occurrence in the Baihetan Reservoir area is positively correlated with slope,surface temperature,and deformation rate,while it is negatively correlated with fault distance and normalized difference vegetation index.Geological lithology exerts minimal influence on the occurrence of landslides,with the risk being low in forest land and high in grassland.The method proposed in this study provides a useful reference for disaster prevention and mitigation departments to perform landslide hazard susceptibility evaluations in deep canyon areas under complex geological conditions. 展开更多
关键词 Baihetan SBAS-InSAR SSA-BP Landslide hazard susceptibility evaluation
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Comparative evaluation of commercial Douchi by different molds:biogenic amines,non-volatile and volatile compounds 被引量:1
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作者 Aijun Li Gang Yang +4 位作者 Zhirong Wang Shenglan Liao Muying Du Jun Song Jianquan Kan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期434-443,共10页
To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fer... To provide new insights into the development and utilization of Douchi artificial starters,three common strains(Aspergillus oryzae,Mucor racemosus,and Rhizopus oligosporus)were used to study their influence on the fermentation of Douchi.The results showed that the biogenic amine contents of the three types of Douchi were all within the safe range and far lower than those of traditional fermented Douchi.Aspergillus-type Douchi produced more free amino acids than the other two types of Douchi,and its umami taste was more prominent in sensory evaluation(P<0.01),while Mucor-type and Rhizopus-type Douchi produced more esters and pyrazines,making the aroma,sauce,and Douchi flavor more abundant.According to the Pearson and PLS analyses results,sweetness was significantly negatively correlated with phenylalanine,cysteine,and acetic acid(P<0.05),bitterness was significantly negatively correlated with malic acid(P<0.05),the sour taste was significantly positively correlated with citric acid and most free amino acids(P<0.05),while astringency was significantly negatively correlated with glucose(P<0.001).Thirteen volatile compounds such as furfuryl alcohol,phenethyl alcohol,and benzaldehyde caused the flavor difference of three types of Douchi.This study provides theoretical basis for the selection of starting strains for commercial Douchi production. 展开更多
关键词 DOUCHI Starting strains Non-volatile compounds Volatile compounds Sensory evaluation
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Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data 被引量:1
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作者 Yan-Yan Ding Yang-Bo Nie +9 位作者 Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期145-159,共15页
A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°an... A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic Energy.The leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight method.The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 cm.The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and JEFF-3.3.Based on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were analyzed.The results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results. 展开更多
关键词 Leakage neutron spectra URANIUM D-T neutron source evaluated nuclear data
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Identification and evaluation of shale oil micromigration and its petroleum geological significance 被引量:2
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作者 HU Tao JIANG Fujie +10 位作者 PANG Xiongqi LIU Yuan WU Guanyun ZHOU Kuo XIAO Huiyi JIANG Zhenxue LI Maowen JIANG Shu HUANG Liliang CHEN Dongxia MENG Qingyang 《Petroleum Exploration and Development》 SCIE 2024年第1期127-140,共14页
Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil... Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil micro-migration phenomenon.The hydrocarbon micro-migration in shale oil was quantitatively evaluated and verified by a self-created hydrocarbon expulsion potential method,and the petroleum geological significance of shale oil micro-migration evaluation was determined.Results show that significant micro-migration can be recognized between the organic-rich lamina and organic-poor lamina.The organic-rich lamina has strong hydrocarbon generation ability.The heavy components of hydrocarbon preferentially retained by kerogen swelling or adsorption,while the light components of hydrocarbon were migrated and accumulated to the interbedded felsic or carbonate organic-poor laminae as free oil.About 69% of the Fengcheng Formation shale samples in Well MY1 exhibit hydrocarbon charging phenomenon,while 31% of those exhibit hydrocarbon expulsion phenomenon.The reliability of the micro-migration evaluation results was verified by combining the group components based on the geochromatography effect,two-dimension nuclear magnetic resonance analysis,and the geochemical behavior of inorganic manganese elements in the process of hydrocarbon migration.Micro-migration is a bridge connecting the hydrocarbon accumulation elements in shale formations,which reflects the whole process of shale oil generation,expulsion and accumulation,and controls the content and composition of shale oil.The identification and evaluation of shale oil micro-migration will provide new perspectives for dynamically differential enrichment mechanism of shale oil and establishing a“multi-peak model in oil generation”of shale. 展开更多
关键词 shale oil micro-migration identification micro-migration evaluation Junggar Basin Mahu Sag Lower Permian Fengcheng Formation hydrocarbon expulsion potential method
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Evaluating grant proposals:lessons from using metrics as screening device
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作者 Katerina Guba Alexey Zheleznov Elena Chechik 《Journal of Data and Information Science》 CSCD 2023年第2期66-92,共27页
Purpose:This study examines the effects of using publication-based metrics for the initial screening in the application process for a project leader.The key questions are whether formal policy affects the allocation o... Purpose:This study examines the effects of using publication-based metrics for the initial screening in the application process for a project leader.The key questions are whether formal policy affects the allocation of funds to researchers with a better publication record and how the previous academic performance of principal investigators is related to future project results.Design/methodology/approach:We compared two competitions,before and after the policy raised the publication threshold for the principal investigators.We analyzed 9,167 papers published by 332 winners in physics and the social sciences and humanities(SSH),and 11,253 publications resulting from each funded project.Findings:We found that among physicists,even in the first period,grants tended to be allocated to prolific authors publishing in high-quality journals.In contrast,the SSH project grantees had been less prolific in publishing internationally in both periods;however,in the second period,the selection of grant recipients yielded better results regarding awarding grants to more productive authors in terms of the quantity and quality of publications.There was no evidence that this better selection of grant recipients resulted in better publication records during grant realization.Originality:This study contributes to the discussion of formal policies that rely on metrics for the evaluation of grant proposals.The Russian case shows that such policy may have a profound effect on changing the supply side of applicants,especially in disciplines that are less suitable for metric-based evaluations.In spite of the criticism given to metrics,they might be a useful additional instrument in academic systems where professional expertise is corrupted and prevents allocation of funds to prolific researchers. 展开更多
关键词 Grant funding Research evaluation Publication-based metrics Funding allocation
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Evaluating Parameterizations for Turbulent Fluxes over the Landfast Sea-Ice Surface in Prydz Bay, Antarctica
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作者 Fangyuan CHENG Qinghua YANG +3 位作者 Changwei LIU Bo HAN Shijie PENG Guanghua HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第10期1816-1832,共17页
It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East Antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes... It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East Antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes over the landfast seaice surface in five numerical models.The Community Noah Land Surface Model with Multi-Parameterizations Options(Noah_mp)best replicates the turbulent momentum flux,while the Beijing Climate System Model(BCC_CSM)produces the optimum sensible and latent heat fluxes.In particular,two critical issues of parameterization schemes,stability functions and roughness lengths,are investigated.Sensitivity tests indicate that roughness lengths play a decisive role in model performance.Based on the observed turbulent fluxes,roughness lengths over the landfast sea-ice surface are calculated.The results,which can provide a basis for setting up model parameters,reveal that the dynamic roughness length(z0m)increases with the increase of frictional velocity(u*)when u*≤0.4 m s^(−1) and fluctuates around 10^(−3 )m when u*>0.4 m s^(−1);thermal roughness length(z0t)is linearly related to the temperature gradient between air and sea-ice surface(ΔT)with a relation of lg(z0t)=−0.29ΔT−3.86;and the mean water vapor roughness length(z0q)in the specific humidity gradient(Δq)range ofΔq≤−0.6 g kg^(−1) is 10^(−6) m,3.5 times smaller than that in the range ofΔq˃−0.6 g kg^(−1). 展开更多
关键词 turbulent fluxes ANTARCTICA landfast sea-ice surface PARAMETERIZATION evaluating numerical models
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Method for evaluation of geological strength index of carbonate cliff rocks:Coupled hyperspectral-digital borehole image technique 被引量:1
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作者 Haiqing Yang Guizhong Huang +3 位作者 Chiwei Chen Yong Yang Qi Wang Xionghui Dai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4204-4215,共12页
The deterioration of unstable rock mass raised interest in evaluating rock mass quality.However,the traditional evaluation method for the geological strength index(GSI)primarily emphasizes the rock structure and chara... The deterioration of unstable rock mass raised interest in evaluating rock mass quality.However,the traditional evaluation method for the geological strength index(GSI)primarily emphasizes the rock structure and characteristics of discontinuities.It ignores the influence of mineral composition and shows a deficiency in assessing the integrity coefficient.In this context,hyperspectral imaging and digital panoramic borehole camera technologies are applied to analyze the mineral content and integrity of rock mass.Based on the carbonate mineral content and fissure area ratio,the strength reduction factor and integrity coefficient are calculated to improve the GSI evaluation method.According to the results of mineral classification and fissure identification,the strength reduction factor and integrity coefficient increase with the depth of rock mass.The rock mass GSI calculated by the improved method is mainly concentrated between 40 and 60,which is close to the calculation results of the traditional method.The GSI error rates obtained by the two methods are mostly less than 10%,indicating the rationality of the hyperspectral-digital borehole image coupled evaluation method.Moreover,the sensitivity of the fissure area ratio(Sr)to GSI is greater than that of the strength reduction factor(a),which means the proposed GSI is suitable for rocks with significant fissure development.The improved method reduces the influence of subjective factors and provides a reliable index for the deterioration evaluation of rock mass. 展开更多
关键词 Hyperspectral image Digital panoramic borehole image Geological strength index Carbonate rock mass Quantitative evaluation
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Evaluating the weekly changes in terrestrial water storage estimated by two different inversion strategies in the Amazon River Basin
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作者 Bo Zhong Xianpao Li +2 位作者 Qiong Li Jiangtao Tan Xianyun Dai 《Geodesy and Geodynamics》 EI CSCD 2023年第6期614-626,共13页
In this study,we estimated the weekly Gravity Recovery and Climate Experiment(GRACE)spherical harmonic(SH)solutions and regional mascon solutions using GRACE-based Geopotential Difference(GPD)data and investigated the... In this study,we estimated the weekly Gravity Recovery and Climate Experiment(GRACE)spherical harmonic(SH)solutions and regional mascon solutions using GRACE-based Geopotential Difference(GPD)data and investigated their abilities in retrieving terrestrial water storage(TWS)changes over the Amazon River Basin(ARB)from January 2003 to February 2013.The performance of the weekly GPD-SH and GPDmascon solutions was evaluated by comparing them with the weekly GFZ-SH solutions,Global Land Data Assimilation Systems(GLDAS)-NOAH hydrological model outputs,and monthly GFZ-SH,GPD-SH,and CSRmascon solutions in the spatio-temporal and spectral domains.The results demonstrate that the weekly GPD-SH and GPD-mascon present good consistency with the weekly GFZ-SH solutions and GLDAS-NOAH estimates in the spatio-temporal domains,but GPD-mascon presents stronger signal amplitudes and more spatial details.The comparison of the monthly average of weekly estimates and monthly solutions demonstrates that the weekly GPD-mascon and GFZ-SH with DDK1 filtering are close to the monthly CSRmascon and GFZ-SH solutions,respectively.However,the signal amplitudes of TWS changes from GPD-SH and GFZ-SH with 650 km Gaussian filtering are smaller than the monthly solutions,and the corresponding Root Mean Square Errors between the TWS change time series from the monthly average of weekly solutions and monthly estimates are 18.12 mm(GPD-mascon),18.81 mm(GFZ-SH-DDK1),24.93 mm(GPDSH-G650km),and 33.07 mm(GFZ-SH-G650km),respectively.Additionally,the TWS change time series derived from weekly solutions present more high-frequency time-varying information than monthly solutions.Furthermore,the 300 km Gaussian filtering can improve the signal amplitudes of TWS changes from the weekly GPD-SH solutions more than those with 650 km Gaussian filtering,but the corresponding noise level is higher.The weekly GPD-SH and GPD-mascon solutions can extend the application scopes of GRACE and provide good complements to the current GRACE monthly solutions. 展开更多
关键词 Terrestrial water storage change Amazon River Basin GRACE-based geopotential differences Weekly solutions Performance evaluation
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Comprehensive Evaluation of Flower Border Application Value of New and Superior Plants in Hefei Area 被引量:1
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作者 MENG Yi ZHAO Zhiyan +1 位作者 LIANG Tingwu LU Zhaoliang 《Journal of Landscape Research》 2024年第2期69-71,76,共4页
An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinc... An analytic hierarchy process(AHP)was employed to assess the applicability of 18 new and superior varieties of flowers in Hefei City flower border applications.A total of 12 indicators were selected from three distinct aspects of adaptability,ornamental characteristics and use traits,in order to establish a comprehensive evaluation model.The results demonstrate that grade I(J≥2.685)exhibits excellent application value,encompassing six species of plants,such asHydrangeamacrophylla‘Endless Summer’;grade II(2.684≤J≤2.420)is also of notable application value,encompassing five species of plants,such asCallistemonrigidus;grade III(2.419≤J≤2.615)is of average application value,including five species of plants,such asCrocosmiacrocosmiflora;grade IV(J≤2.16)is of relatively poor application value.The evaluation results may be utilized as a theoretical reference for the promotion of new and superior varieties in the flower border of Hefei. 展开更多
关键词 Analytic hierarchy process(AHP) New and superior variety Application value Comprehensive evaluation
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Evaluation Test Research of DR Inspection System for Circumferential Welds in Long Distance Pipeline
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作者 WANG Changjiang WANG Xue +4 位作者 ZHANG Shimin ZHAO Yan LYU Xinyu ZHONG Qian ZHOU Guangyan 《材料导报》 EI CAS CSCD 北大核心 2024年第22期223-229,共7页
Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digit... Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digital radiographic testing and fully evaluate the integrated system inspection ability of equipment,personnel,and processes,a scientific and standardized evaluation method to the system is very necessary.Here investigates the precedents of relevant non-destructive testing evaluation methods at home and abroad,considers the testing characteristics of DR equipment,develops a complete set of DR testing system evaluation procedures.It deeply studies the adaptability methods of program processes from defect production to slicing processing and data statistical calculation for digital radiographic testing evaluation.To check the repeatability and reliability of the detectable system,five process welds with 200 real metallographic defects were fabricated in the laboratory.From the detected results,the DR system has good repeatability in image quality,and the detectable defect size reaches 0.85 mm under achieving 90%detection probability at a confidence level of 95%,the error of detected defect length is±2 mm,and the error of detected defect localization is±5 mm.The qualitative and quantitative detection of defects are accurate and reliable.The test further confirmed the reliable detection ability of the DR detection system,and fully validated the scientific and practical evaluation method designed.The research on the evaluation test method can serve as an important link in the quality control system for the on-site application of digital ray equipment in long-distance pipelines.The designed program,test,and evaluation content can serve as an important basis for the formulation of relevant specifications or standards. 展开更多
关键词 digital ray evaluation test REPEATABILITY RELIABILITY
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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network
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作者 Xue-Qiang Zhang Qing-Lin Cheng +2 位作者 Wei Sun Yi Zhao Zhi-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期621-640,共20页
As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crud... As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems. 展开更多
关键词 Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction
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PARE:Privacy-Preserving Data Reliability Evaluation for Spatial Crowdsourcing in Internet of Things
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作者 Peicong He Yang Xin Yixian Yang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3067-3084,共18页
The proliferation of intelligent,connected Internet of Things(IoT)devices facilitates data collection.However,task workers may be reluctant to participate in data collection due to privacy concerns,and task requesters... The proliferation of intelligent,connected Internet of Things(IoT)devices facilitates data collection.However,task workers may be reluctant to participate in data collection due to privacy concerns,and task requesters may be concerned about the validity of the collected data.Hence,it is vital to evaluate the quality of the data collected by the task workers while protecting privacy in spatial crowdsourcing(SC)data collection tasks with IoT.To this end,this paper proposes a privacy-preserving data reliability evaluation for SC in IoT,named PARE.First,we design a data uploading format using blockchain and Paillier homomorphic cryptosystem,providing unchangeable and traceable data while overcoming privacy concerns.Secondly,based on the uploaded data,we propose a method to determine the approximate correct value region without knowing the exact value.Finally,we offer a data filtering mechanism based on the Paillier cryptosystem using this value region.The evaluation and analysis results show that PARE outperforms the existing solution in terms of performance and privacy protection. 展开更多
关键词 Spatial crowdsourcing PRIVACY-PRESERVING data evaluation IOT blockchain
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Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network
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作者 YÜNKÜL Kaan KARAÇOR Fatih +1 位作者 GÜRBÜZ Ayhan BUDAK TahsinÖmür 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3108-3122,共15页
This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results... This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement devices.Although water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression analyses.In non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded soil.Feed-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic modeling.The experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for testing.It was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression analyses.Furthermore,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination. 展开更多
关键词 Undrained shear strength Liquidity index Water content ratio non-linear regression Artificial neural networks Fuzzy logic
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A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT
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作者 Xiao Feng Zheng Yuan 《Computers, Materials & Continua》 SCIE EI 2024年第2期1881-1895,共15页
First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism... First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction records.We weight the time attenuation factor to each historical interaction record for updating and got the new historical record data.We refer to the beta distribution to enhance the flexibility and adaptability of the direct trust assessment model to better capture time trends in the historical record.Then we propose an autoencoder-based trust clustering algorithm.We perform feature extraction based on autoencoders.Kullback leibler(KL)divergence is used to calculate the reconstruction error.When constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency and introduce sparse constraints into the hidden layer of the autoencoder.The sparse penalty term in the loss function measures the difference through the KL divergence.Trust clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering algorithm.During the clustering process,edge nodes have a variety of trustworthy attribute characteristics.We assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of distance.Finally,we introduced adaptive weights to calculate comprehensive trust evaluation.Simulation experiments prove that our trust evaluation mechanism has excellent reliability and accuracy. 展开更多
关键词 Cross-domain authentication trust evaluation autoencoder
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Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon
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作者 Samira Zoa Assoumou Ulrich Leger Davy Mouangala +6 位作者 Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema 《Advances in Infectious Diseases》 CAS 2024年第2期469-477,共9页
1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is... 1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to December 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission. 展开更多
关键词 SARS-CoV-2 Rapid Diagnostic Test evaluATION COVID-19 ANTIGEN Performance
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Machine learning in metal-ion battery research: Advancing material prediction, characterization, and status evaluation
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作者 Tong Yu Chunyang Wang +1 位作者 Huicong Yang Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期191-204,I0006,共15页
Metal-ion batteries(MIBs),including alkali metal-ion(Li^(+),Na^(+),and K^(3)),multi-valent metal-ion(Zn^(2+),Mg^(2+),and Al^(3+)),metal-air,and metal-sulfur batteries,play an indispensable role in electrochemical ener... Metal-ion batteries(MIBs),including alkali metal-ion(Li^(+),Na^(+),and K^(3)),multi-valent metal-ion(Zn^(2+),Mg^(2+),and Al^(3+)),metal-air,and metal-sulfur batteries,play an indispensable role in electrochemical energy storage.However,the performance of MIBs is significantly influenced by numerous variables,resulting in multi-dimensional and long-term challenges in the field of battery research and performance enhancement.Machine learning(ML),with its capability to solve intricate tasks and perform robust data processing,is now catalyzing a revolutionary transformation in the development of MIB materials and devices.In this review,we summarize the utilization of ML algorithms that have expedited research on MIBs over the past five years.We present an extensive overview of existing algorithms,elucidating their details,advantages,and limitations in various applications,which encompass electrode screening,material property prediction,electrolyte formulation design,electrode material characterization,manufacturing parameter optimization,and real-time battery status monitoring.Finally,we propose potential solutions and future directions for the application of ML in advancing MIB development. 展开更多
关键词 Metal-ion battery Machine learning Electrode materials CHARACTERIZATION Status evaluation
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