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Fuzzy Multi-Criteria Decision Support System for the Best Anti-Aging Treatment Selection Process through Normal Wiggly Hesitant Fuzzy Sets
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作者 Daekook Kang Ramya Lakshmanaraj +5 位作者 Samayan Narayanamoorthy Navaneethakrishnan Suganthi Keerthana Devi Samayan Kalaiselvan Ranganathan Saraswathy Dragan Pamucar Vladimir Simic 《Computers, Materials & Continua》 SCIE EI 2024年第9期4947-4972,共26页
This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment met... This socialized environment among educated and developed people causes themto focusmore on their appearance and health,which turns them towards medical-related treatments,leading us to discuss anti-aging treatment methods for each age group,particularly for urban people who are interested in this.Some anti-aging therapies are used to address the alterations brought on by aging in human life without the need for surgery or negative effects.Five anti-aging therapies such as microdermabrasion or dermabrasion,laser resurfacing anti-aging skin treatments,chemical peels,dermal fillers for aged skin,and botox injections are considered in this study.Based on the criteria of safety risk,investment cost,customer happiness,and side effects,the optimal alternative is picked.As a result,a NormalWiggly Hesitant Pythagorean Fuzzy Set(NWHPFS)is constructed and used in Multi-Criteria Decision-Making(MCDM)using traditional wavy mathematical approaches.The entropy approach is utilized to determine weight values,and the Normal Wiggly Hesitant Pythagorean-VlseKriterijumska Optimizacija I Kompromisno Resenje(NWHPF-VIKOR)method is utilized to rank alternatives using MCDM methodologies.Sensitivity analysis and comparative analysis were performed to ensure the robustness and reliability of the proposed method.The smart final choice will undoubtedly assist Decision Makers(DM)in making the right judgments,and the MCDM approach will undoubtedly assist individuals in understanding the medicine. 展开更多
关键词 normal wiggly hesitant pythagorean fuzzy set hesitant pythagorean fuzzy set anti-aging treatment entropy VIse Kriterijumska Optimizacija I Kompromisno Resenje
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The Pursuit of Unhappiness:The Ground Theory to Explain Why People Choose to Be Unhappy Rather Than Happy
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作者 Michael Galanakis 《Psychology Research》 2023年第2期51-59,共9页
This article presents a ground theory to explain why some individuals choose to be unhappy rather than happy,supported by empirical data collected from a sample of 750 professionals in Greece’s public and private sec... This article presents a ground theory to explain why some individuals choose to be unhappy rather than happy,supported by empirical data collected from a sample of 750 professionals in Greece’s public and private sectors.We begin by reviewing the existing literature on happiness and well-being,highlighting the debate between hedonic and eudaimonic perspectives.We then introduce our research questions and rationale,and describe our methods,sample,and psychometric tools used to measure happiness and other variables of interest.Our results indicate that various factors,including cultural influences,past experiences,and personal values,contribute to individuals’pursuit of unhappiness.We conclude with a thorough discussion of our results and their implications for future research and interventions aimed at promoting well-being. 展开更多
关键词 unhappiness HAPPINESS ground theory empirical data public sector private sector Greece X2 Models R squared
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OBE视域下师范生实验教学能力培养的目标构建
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作者 李文娜 《物理通报》 CAS 2024年第5期94-97,共4页
长期以来在基础教育领域物理实验教学是一个很薄弱的环节,已成为基础教育领域的卡脖子问题,新时代探寻有效的策略,培养师范生实验教学能力,对推进基础教育改革有着非常重要的意义.基于成果导向教育的逻辑,剖析高师院校实验教学能力学习... 长期以来在基础教育领域物理实验教学是一个很薄弱的环节,已成为基础教育领域的卡脖子问题,新时代探寻有效的策略,培养师范生实验教学能力,对推进基础教育改革有着非常重要的意义.基于成果导向教育的逻辑,剖析高师院校实验教学能力学习成果现状及诉求,提出聚焦实验教学能力培养的目标建构策略:基于棱锥思维确定知识结构目标;基于整体思维细分能力目标;基于系统思维聚合课程目标;基于底线思维督促达成目标;基于教改动态调整目标. 展开更多
关键词 师范生 物理实验教学能力 Obe理念
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Identifying the best common factor model via exploratory eactor analysis
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作者 HE Bao-hua TANG Rui TAGN Qi-yi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期24-33,共10页
Currently,there is no solid criterion for judging the quality of the estimators in factor analysis.This paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of fa... Currently,there is no solid criterion for judging the quality of the estimators in factor analysis.This paper presents a new evaluation method for exploratory factor analysis that pinpoints an appropriate number of factors along with the best method for factor extraction.The proposed technique consists of two steps:testing the normality of the residuals from the fitted model via the Shapiro-Wilk test and using an empirical quantified index to judge the quality of the factor model.Examples are presented to demonstrate how the method is implemented and to verify its effectiveness. 展开更多
关键词 factor analysis Shapiro-Wilk normalITY RESIDUALS
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Gravity Fault Subsidence and Beach Ridges Progradation in Quinta-Cassino (RS) Coastal Plain, Brazil
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作者 Bruno Silva da Fontoura Adelir José Strieder +3 位作者 Iran Carlos Stalliviere Corrêa Paulo Rogério Mendes Alexandre Felipe Bruch Angélica Cirolini 《Open Journal of Geology》 CAS 2024年第2期177-195,共19页
Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, howeve... Ground penetrating radar (GPR) surveys have being applied to investigate very near-surface stratification of sedimentary units in coastal plains and to define their depositional conditions. This paper presents, however, low-frequency GPR survey to investigate fault-related depositional systems at greater depths. The Quinta-Cassino area in the Rio Grande do Sul Coastal Plain (RGSCP, Brazil) shows a wide strandplain that is made off by very long, continuous, and linear geomorphic features (beach ridges). This strandplain extends for ~70 km southward. The beach ridges show low-angle truncations against the Quinta escarpment, and also truncations in the strandplain. The traditional approach points that RGSCP was developed by juxtaposition of four lagoons/barrier systems as consequence of sea level changes;previous model assumes that no deformational episode occurred in RGSCP. The geophysical and geological surveys carried out in this area showed the existence of listric fault controlling the beach ridges in the escarpments and hanging-wall blocks. The radargrams could distinguish Pleistocene basement unit anticlockwise rotation, thickening of beach ridges radarfacies close to listric normal faults, and horst structures. These deformational features indicate that the extensional zone of a large-scale gravity-driven structure controlled the mechanical subsidence, the Holocene sedimentation and its stratigraphic and geomorphic features in the Quinta-Cassino area to build up an asymmetric delta. The results point to a new approach in dealing with RGSCP Holocene evolution. 展开更多
关键词 Gravity Tectonics normal Faults Ground Penetrating Radar Survey beach-Ridges Progradation
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Understanding the combustion behavior of electric bicycle batteries and unveiling its relationship with fire extinguishing
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作者 Zhanglong Yu Xueling Shen +6 位作者 Ran Xu Zheng Wang Zengming Wan Mingyang Chen Yi Cui Yanyan Fang Xiaoli Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期609-618,共10页
In this study,a detailed analysis of the combustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was conducted.This research included quantitative mea... In this study,a detailed analysis of the combustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was conducted.This research included quantitative measurements of the combustion duration,flame height,combustion temperature,heat release rate,and total heat release.The results indicated that LMO batteries exhibited higher combustion temperatures of 600–700°C,flame heights of 70–75 cm,a significantly higher heat release rate of40.1 k W(12 Ah),and a total heat release of 1.04 MJ(12 Ah)compared to LFP batteries with the same capacity.Based on these experimental results,a normalized total heat release(NORTHR)parameter was proposed,demonstrating good universality for batteries with different capacities.Utilizing this parameter,quantitative calculations and optimization of the extinguishing agent dosage were conducted for fires involving these two types of batteries,and the method was validated by extinguishing fires for these two types of battery packs with water-based extinguishing fluids. 展开更多
关键词 Combustion behavior Electric bicycle Lithium-ion battery Fire extinguishing normalized total heat release
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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects
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作者 Congxi FANG Jinlei CHEN +4 位作者 Chaojun OUYANG Lu WANG Changfeng SUN Quan ZHANG Jun WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期701-716,共16页
Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ... Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. 展开更多
关键词 Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects
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Hilbert空间中的有界线性算子的几类扩张问题研究
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作者 刘淑雅 吴德玉 《内蒙古大学学报(自然科学版)》 CAS 2024年第1期1-6,共6页
研究了Hilbert空间中有界线性算子的扩张,给出了有界线性算子数值域与其正常扩张、酉扩张数值域的关系式,并给出了可交换扩张的存在性。
关键词 正常扩张 酉扩张 可交换扩张 数值域
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Frictional behavior of quartz gouge during slide-hold-slide considering normal stress oscillation 被引量:1
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作者 Kang Tao Wengang Dang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第3期108-121,共14页
Slide-hold-slide(SHS)test is an essential experimental approach for studying the frictional stability of faults.The origin SHS framework was established based on a consistent constant normal stress,which cannot truly ... Slide-hold-slide(SHS)test is an essential experimental approach for studying the frictional stability of faults.The origin SHS framework was established based on a consistent constant normal stress,which cannot truly reflect the stress disturbance around fault zones.In this paper,we conducted a series of'dynamic SHS tests',which includes normal stress oscillations in the relaxation stage with different oscillation amplitudes and frequencies on synthetic quartz gouge using a double direct shear assembly.The experimental results reveal that the amplitude of the normal load oscillation has a remarkable effect on the frictional relaxation and healing patterns.However,the frequency of the normal load oscillation has a minor effect.Additionally,the shear loading rate is proportional to the normal loading rate during the relaxation stage,and the normal stiffness of the quartz layer remains nearly constant under various loading conditions.The creep rate during the hold phase is not obviously affected by the normal load oscillation,while the precursory slip is also sensitive to the oscillation amplitude.This study provides insights into the evolution of frictional stability in discontinuities and is beneficial for controlling relative disasters in fault zones. 展开更多
关键词 Slide-hold-slide test normal load oscillation Frictional healing Fault stability
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Close relationship between mediators of inflammation and pancreatic cancer:Our experience
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作者 Francesca Vescio Michele Ammendola +1 位作者 Giuseppe Currò Silvia Curcio 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期2927-2930,共4页
In this editorial,we focus specifically on the mechanisms by which pancreatic inflammation affects pancreatic cancer.Cancer of the pancreas remains one of the deadliest cancer types.The highest incidence and mortality... In this editorial,we focus specifically on the mechanisms by which pancreatic inflammation affects pancreatic cancer.Cancer of the pancreas remains one of the deadliest cancer types.The highest incidence and mortality rates of pancreatic cancer are found in developed countries.Trends of pancreatic cancer incidence and mortality vary considerably worldwide.A better understanding of the etiology and identification of the risk factors is essential for the primary prevention of this disease.Pancreatic tumors are characterized by a complex microenvironment that orchestrates metabolic alterations and supports a milieu of interactions among various cell types within this niche.In this editorial,we highlight the foundational studies that have driven our understanding of these processes.In our experimental center,we have carefully studied the mechanisms of that link pancreatic inflammation and pancreatic cancer.We focused on the role of mast cells(MCs).MCs contain pro-angiogenic factors,including tryptase,that are associated with increased angiogenesis in various tumors.In this editorial,we address the role of MCs in angiogenesis in both pancreatic ductal adenocarcinoma tissue and adjacent normal tissue.The assessment includes the density of c-Kit receptor-positive MCs,the density of tryptase-positive MCs,the area of tryptasepositive MCs,and angiogenesis in terms of microvascularization density. 展开更多
关键词 Mast cells C-Kit receptor TRYPTASE Angiogenesis Microvascular density Endothelial area Pancreatic tumor tissue Adjacent normal tissue
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基于改进Crazy Climber算法的小波脊线提取
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作者 赵丽洁 李雯雯 +1 位作者 刘瑾 晋东丽 《兰州理工大学学报》 CAS 北大核心 2024年第1期132-138,共7页
针对传统Crazy Climber算法提取多条小波脊线耗时长、效率低等问题,提出一种模拟正火冷却的改进Crazy Climber脊线提取算法.通过对结构振动的响应进行连续小波变换,在小波系数幅值构成的时频平面中,基于模拟正火冷却算法跟踪提取时频平... 针对传统Crazy Climber算法提取多条小波脊线耗时长、效率低等问题,提出一种模拟正火冷却的改进Crazy Climber脊线提取算法.通过对结构振动的响应进行连续小波变换,在小波系数幅值构成的时频平面中,基于模拟正火冷却算法跟踪提取时频平面中的小波脊点,促使每一个随机点高速地聚集在脊线上,消减运算时间.通过单自由度和多自由度系统数值模拟,与传统Crazy Climber算法在计算效率和识别精度两者进行对比分析,验证改进算法的的优越性. 展开更多
关键词 小波变换 脊线提取 Crazy Climber算法 正火冷却
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HBeAg阳性ALT正常不确定期患者肝组织纤维化程度及影响因素分析 被引量:1
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作者 刘立 李俊义 +4 位作者 常丽仙 牟春燕 张映媛 董志坚 刘春云 《中西医结合肝病杂志》 CAS 2024年第4期310-314,共5页
目的:分析乙型肝炎e抗原(HBeAg)阳性丙氨酸氨基转移酶(ALT)正常不确定期患者肝脏组织纤维化程度,为HBeAg阳性ALT正常不确定期患者的病情判断提供依据。方法:选取2017年1月至2021年12月HBeAg阳性ALT正常乙型肝炎病毒载量(HBV DNA)水平低... 目的:分析乙型肝炎e抗原(HBeAg)阳性丙氨酸氨基转移酶(ALT)正常不确定期患者肝脏组织纤维化程度,为HBeAg阳性ALT正常不确定期患者的病情判断提供依据。方法:选取2017年1月至2021年12月HBeAg阳性ALT正常乙型肝炎病毒载量(HBV DNA)水平低于2×10^(7)IU/ml且高于20 IU/ml者作为研究对象,对该类患者进行肝组织病理学检查,并收集患者年龄、性别、感染HBV时间、肝功能、乙型肝炎表面抗原(HBsAg)水平、HBV DNA载量、基因型、门静脉内径、脾静脉内径、脾脏厚度等,Logistic回归分析患者肝组织纤维化的影响因素,受试者工作特征(ROC)曲线及相关参数评价其效能。结果:178例患者中,Scheuer法分期:S0期6例(3.4%),S1期67例(37.6%),S2期83例(46.6%),S3期14例(7.9%),S4期8例(4.5%),纤维化程度≥S2期105例(59.0%)。Logistic回归分析肝组织显著纤维化与感染时间(OR=1.101,95%CI=1.000~1.212;P=0.049)、HBV DNAlg(OR=1.280,95%CI=1.023~1.600;P=0.031)、门静脉内径(OR=1.611,95%CI=1.100~2.360;P=0.014)和脾脏厚度(OR=1.276,95%CI=1.107~1.469;P=0.001)独立相关,ROC曲线下面积(AUC)分别为0.67、0.62、0.70、0.67,天门冬氨酸氨基转移酶/血小板(APRI)和肝纤维化4因子指数(FIB-4)的AUC分别为0.68、0.57。结论:HBeAg阳性ALT正常不确定期患者中,有相当比例的患者纤维化程度≥S2,具有抗病毒治疗的指征。感染时间、HBV DNA、门静脉内径和脾脏厚度可能对预测其肝组织显著纤维化有一定的临床价值。 展开更多
关键词 HbeAG阳性 ALT正常 肝组织纤维化程度 不确定期
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Rheological Characterization of Systems with Plastic Flow Behavior
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作者 Dimiter Hadjistamov 《材料科学与工程(中英文A版)》 2024年第1期11-17,共7页
Model suspensions with plastic flow behavior were investigated rheologically.Shear stress and first normal stress difference were measured simultaneously with shear flow start-up experiments.After the shear deformatio... Model suspensions with plastic flow behavior were investigated rheologically.Shear stress and first normal stress difference were measured simultaneously with shear flow start-up experiments.After the shear deformation is stopped,the stress relaxation begins,residual shear stress can appear.The relative residual shear stressτRR is the ratio of the residual shear stress to the steady state shear stress.The relative residual shear stress is considered as a measure of the structure of the system.In the case ofτRR=0.98,we assume that an elastic to plastic deformation is occurred,which is the yield point.The system with 7.5%Aerosil 380 has achieved withτRR=0.95 in the first approximation the transition to plastic flow,this is the yield point for the system,with a yield stress of 23 Pa.This is the only one known system with yield point.The systems withτRR>0.30 andτRR<0.95 at the first point,have no transition from elastic to plastic flow,but the structure is strongly destroyed.Analogous to the above,the shear stress at this point will be called yield stress.One requirement is that the start-up experiment is determined with a very low shear rate¾0.00071/s or 0.000961/s.The associated normal stress to the yield stress is called normal yield stress.The dependence of the normal stress of the systems with Aerosil 380 on the shear stress reached,after a short increase/decrease in the values,the straight line of the normal stress/shear stress of the liquid phase M20000.A linear relationship between normal stress and shear stress was found in the systems with Bentone 27 in Araldite GY260.With a certain measured normal stress/shear stress point,you can draw a straight line with 45°in the double logarithmic plot¾a way to receive the normal stress/shear stress points. 展开更多
关键词 RHEOLOGY yield point yield stress normal stress-shear stress.
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New Probability Distributions in Astrophysics: XIII. Truncation for the Benini Distribution
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作者 Lorenzo Zaninetti 《International Journal of Astronomy and Astrophysics》 2024年第3期203-219,共17页
In order to introduce a right truncated version of the Benini distribution, we derive its probability density function, its distribution function, its average value, its kth moment about the origin, its median, how to... In order to introduce a right truncated version of the Benini distribution, we derive its probability density function, its distribution function, its average value, its kth moment about the origin, its median, how to randomly generate its values, and the maximum likelihood estimator for its three unknown parameters. The astrophysical application of the Benini distribution and its right truncated version is to the initial mass function for stars. 展开更多
关键词 Stars: normal Stars: Luminosity Function Mass Function Stars: Statistics
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Study on Key Biological Indicators of Diabetes Based on Statistical Tests
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作者 Shuaibin Yang 《Journal of Clinical and Nursing Research》 2024年第7期267-273,共7页
Normality testing is a fundamental hypothesis test in the statistical analysis of key biological indicators of diabetes.If this assumption is violated,it may cause the test results to deviate from the true value,leadi... Normality testing is a fundamental hypothesis test in the statistical analysis of key biological indicators of diabetes.If this assumption is violated,it may cause the test results to deviate from the true value,leading to incorrect inferences and conclusions,and ultimately affecting the validity and accuracy of statistical inferences.Considering this,the study designs a unified analysis scheme for different data types based on parametric statistical test methods and non-parametric test methods.The data were grouped according to sample type and divided into discrete data and continuous data.To account for differences among subgroups,the conventional chi-squared test was used for discrete data.The normal distribution is the basis of many statistical methods;if the data does not follow a normal distribution,many statistical methods will fail or produce incorrect results.Therefore,before data analysis and modeling,the data were divided into normal and non-normal groups through normality testing.For normally distributed data,parametric statistical methods were used to judge the differences between groups.For non-normal data,non-parametric tests were employed to improve the accuracy of the analysis.Statistically significant indicators were retained according to the significance index P-value of the statistical test or corresponding statistics.These indicators were then combined with relevant medical background to further explore the etiology leading to the occurrence or transformation of diabetes status. 展开更多
关键词 Diabetes diagnosis Statistical test Nonparametric statistics normality test
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Experimental investigation on shear strength deterioration at the interface between different rock types under cyclic loading
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作者 Qiong Wu Zhiqi Liu +6 位作者 Huiming Tang Liangqing Wang Xiaoxue Huo Zhen Cui Shiyu Li Bo Zhang Zhiwei Lin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3063-3079,共17页
The shear strength deterioration of bedding planes between different rock types induced by cyclic loading is vital to reasonably evaluate the stability of soft and hard interbedded bedding rock slopes under earthquake... The shear strength deterioration of bedding planes between different rock types induced by cyclic loading is vital to reasonably evaluate the stability of soft and hard interbedded bedding rock slopes under earthquake;however,rare work has been devoted to this subject due to lack of attention.In this study,experimental investigations on shear strength weakening of discontinuities with different joint wall material(DDJM)under cyclic loading were conducted by taking the interface between siltstone and mudstone in the Shaba slope of Yunnan Province,China as research objects.A total of 99 pairs of similar material samples of DDJM(81 pairs)and discontinuities with identical joint wall material(DIJM)(18 pairs)were fabricated by inserting plates,engraved with typical surface morphology obtained by performing three-dimensional laser scanning on natural DDJMs sampled from field,into mold boxes.Cyclic shear tests were conducted on these samples to study their shear strength changes with the cyclic number considering the effects of normal stress,joint surface morphology,shear displacement amplitude and shear rate.The results indicate that the shear stress vs.shear displacement curves under each shear cycle and the peak shear strength vs.cyclic number curves of the studied DDJMs are between those of DIJMs with siltstone and mudstone,while closer to those of DIJMs with mudstone.The peak shear strengths of DDJMs exhibit an initial rapid decline followed by a gradual decrease with the cyclic number and the decrease rate varies from 6%to 55.9%for samples with varied surface morphology under different testing conditions.The normal stress,joint surface morphology,shear displacement amplitude and shear rate collectively influence the shear strength deterioration of DDJM under cyclic shear loading,with the degree of influence being greater for larger normal stress,rougher surface morphology,larger shear displacement amplitude and faster shear rate. 展开更多
关键词 Discontinuities with different joint wall material(DDJM) Discontinuities with identical joint wall material(DIJM) Cyclic shear test Shear strength deterioration Joint surface morphology Shear displacement amplitude Shear rate normal stress
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Experimental Studies on Cyclic Shear Behavior of Steel-Clay Interface Under Constant Normal Load
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作者 YU Shi-wen WANG Jie +1 位作者 LIU Jun-wei WANG Teng 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期519-524,共6页
The degradation of the shear stress between pile-clay interface caused by undrained cyclic jacking affects the jacking force.A series of large displacement monotonic shear,cyclic shear and post-cyclic monotonic steel ... The degradation of the shear stress between pile-clay interface caused by undrained cyclic jacking affects the jacking force.A series of large displacement monotonic shear,cyclic shear and post-cyclic monotonic steel plate-clay interface shear te sts were performed under the constant normal load(CNL)condition to inve stigate the effects of normal stre ss,cyclic amplitude,and number of cycles on a steel plate-clay interface using the GDS multi-function interface shear tester.Based on the experimental results,in monotonic shear tests,change of shear stress took place in the specimen,the shear stress rapidly reached the peak value at shear displacement of 1 mm,and then abruptly decreased to the residual value.In cyclic shear te sts,accumulated displacement was a better parameter to describe the soil degradation characteristics,and the degradation degree of shear stress became greater with the increasing of normal stress and accumulated displacement.Shear stress in post-cyclic monotonic shear tests did not generate a peak value and was lower than that in monotonic shear tests under the same normal stress.The soil was completely disturbed and reached the residual strength when the cumulative displacement approached 6 m.An empirical equation to evaluate shear stress degradation mechanism was formulated and the procedure of parameter identification was presented. 展开更多
关键词 cyclic shear steel-clay interface constant normal load cumulative displacement residual strength
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Numerical Investigations on the Transient Behavior of Sand Waves in Beibu Gulf Under Normal and Extreme Sea Conditions
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作者 ZANG Zhi-peng XIE Bo-tao +2 位作者 CHENG Liang HE Fang ZOU Xing 《China Ocean Engineering》 SCIE EI CSCD 2023年第2期232-246,共15页
In this study, a morphodynamic numerical model is established with the Regional Ocean Modeling System(ROMS)to investigate the transient behavior of sand waves under realistic sea conditions. The simulation of sand wav... In this study, a morphodynamic numerical model is established with the Regional Ocean Modeling System(ROMS)to investigate the transient behavior of sand waves under realistic sea conditions. The simulation of sand wave evolution comprises two steps: 1) a regional-scale model is configured first to simulate the ocean hydrodynamics, i.e., tides and tidal currents, and 2) the transient behavior of sand waves is simulated in a small computational domain under the time-variant currents extracted from the large model. The evolution of sand waves on the continental shelf in the Beibu Gulf is specifically investigated. The numerical results of the two-year evolution of sand waves under normal sea conditions compare well with the field survey data. The transient behavior of sand waves in individual months shows that the sand waves are more stable in April and October than that in other months, which can be selected as the windows for seabed operations. The effects of sediment properties, including settling velocity, critical shear stress and surface erosion rate, on sand wave evolution are also analyzed. Then, the typhoon-induced currents are further superimposed on the tidal currents as the extreme weather conditions. Sand waves with the average wavelength generally have more active behavior than smaller or larger sand waves. The characteristics of the evolution of sand waves in an individual typhoon process are quite different for different hydrodynamic combinations. For the storm conditions, i.e., the real combination and maximum combination cases, the sand waves experience a significant migration together with a damping in height due to the dominant suspended sediment transport. For the mild conditions, i.e., the pure tidal current and minimum combination cases, the sand waves migrate less, but the heights continue growing due to the dominant bedload transport. 展开更多
关键词 sand waves morphodynamic numerical model normal sea condition extreme sea conditions transient behaviors
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OBE教育理念下的全科型教师培养
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作者 孙雅君 《淮北职业技术学院学报》 2024年第1期72-76,共5页
培养全科型教师顺应了教育改革及教师专业发展的潮流。OBE理念强调以学生为中心,以学习成果为导向,以持续改进为重点。针对师范生培养在专业化能力、课程设置、职业认同感等方面存在的问题,基于OBE理念从明确培养目标、优化课程内容、... 培养全科型教师顺应了教育改革及教师专业发展的潮流。OBE理念强调以学生为中心,以学习成果为导向,以持续改进为重点。针对师范生培养在专业化能力、课程设置、职业认同感等方面存在的问题,基于OBE理念从明确培养目标、优化课程内容、创新教学方法、完善评价体系等方面提出多元化的培养策略。将OBE理念引入高等院校师范生培养体现了小学教育专业人才培养的要求,提升了师范专业学生的就业竞争力。 展开更多
关键词 Obe理念 全科型教师 师范生培养
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半连续Bernoulli-Normal两部回归模型及变量选择
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作者 鲁亚会 江涛 《统计与决策》 北大核心 2023年第7期52-57,共6页
对于半连续两部回归模型,考虑到每个回归部分都会遇到大量的候选变量,此时就会产生变量选择问题。文章主要研究Bernoulli-Normal两部回归模型的变量选择问题。先提出一种基于Lasso惩罚函数的变量选择方法,但考虑到Lasso估计量不具有Ora... 对于半连续两部回归模型,考虑到每个回归部分都会遇到大量的候选变量,此时就会产生变量选择问题。文章主要研究Bernoulli-Normal两部回归模型的变量选择问题。先提出一种基于Lasso惩罚函数的变量选择方法,但考虑到Lasso估计量不具有Oracle性质,又提出一种基于自适应Lasso惩罚函数的变量选择方法。模拟结果表明:两种方法都能够对Bernoulli-Normal回归模型进行变量选择,且自适应Lasso方法的变量选择性能往往优于Lasso方法。 展开更多
关键词 bernoulli-normal回归模型 变量选择 Lasso惩罚 自适应Lasso惩罚
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