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R/S Analysis and its Application in the Forecast of Mine Inflows 被引量:14
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作者 YANG Yong-guo YUAN Jian-fei CHEN Suo-zhong 《Journal of China University of Mining and Technology》 EI 2006年第4期425-428,共4页
In this paper, the status quo and modeling principles of R/S analysis of non-linear theory are introduced and reviewed. Given the hydro-geological conditions of the Wutongzhuang coal mine, Hurst exponents of mine infl... In this paper, the status quo and modeling principles of R/S analysis of non-linear theory are introduced and reviewed. Given the hydro-geological conditions of the Wutongzhuang coal mine, Hurst exponents of mine inflow for the main shaft, venti- lating shaft and auxiliary shaft were obtained using R/S analysis, which are 0.772 0, 0.824 7 and 0.905 1 respectively. Since all of the three Hurst exponents are larger than 0.5, it can be concluded that the trend of mine inflow are a long-term as well as persistent problem. Based on the level of duration, the shafts can be listed in decreasing order as the auxiliary shaft, the ventilation shaft and the main shaft, which appears identical with the actual situation of the mine inflow. With R/S analysis, a new method for long-term forecasting of mine inflows is provided. 展开更多
关键词 r/s analysis Wutongzhuang coal mine mine inflow forecasting Hurst exponents
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Impact of dietary nutrition regimens based on body composition analysis on bone metabolism in Alzheimer’s disease patients
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作者 Xue-Lian Wang Yi-Ran Zhao +3 位作者 Ying Yu Zhi-Fang Mao Su-Xian Tan Shan-Shan Yu 《World Journal of Psychiatry》 2025年第2期59-68,共10页
BACKGROUND Body composition analysis(BCA)is primarily used in the management of conditions such as obesity and endocrine disorders.However,its potential in providing nutritional guidance for patients with Alzheimer’s... BACKGROUND Body composition analysis(BCA)is primarily used in the management of conditions such as obesity and endocrine disorders.However,its potential in providing nutritional guidance for patients with Alzheimer’s disease(AD)remains relatively unexplored.AIM To explore the clinical efficacy of BCA-based dietary nutrition scheme on bone metabolism in AD patients.METHODS This retrospective study included 96 patients with AD complicated by osteoporosis who were admitted to The Third Hospital of Quzhou between January 2023 and December 2024.Based on data from previous similar studies,the patients were randomly assigned to either a routine diet(RD)group(n=48)or a personalized nutrition(PN)group(n=48).The RD group received conventional dietary guidance,while the PN group received individualized diet intervention measures based on human BCA.The intervention period lasted for 12 weeks.Bone mineral density(BMD),body mass index(BMI),muscle mass,mineral content,osteocalcin,25-hydroxyvitamin D,procollagen type I N-terminal propeptide(PINP),beta C-terminal telopeptide of type I collagen(β-CTX),and serum calcium were measured and compared between the two groups before and 12 weeks after the intervention.RESULTS No significant differences were observed between groups in terms of age,sex,height,BMI,or other baseline data(P>0.05).In both groups,BMI did not show significant changes after the intervention(P>0.05),whereas muscle mass and mineral content were significantly increased(P<0.05).After the intervention,BMI in the PN group did not differ significantly from that of the RD group,but muscle mass and mineral content were significantly higher in the PN group(P<0.05).After the intervention,a higher proportion of patients in the PN group had a T score>-1 compared to the RD group(P<0.05).The mini-mental state examination(MMSE)score was similar in both groups before the intervention.However,12 weeks after the intervention,the MMSE score in the PN group was significantly higher than that in the RD group(P<0.05).In both groups,the MMSE score significantly increased 12 weeks post-intervention compared to pre-intervention levels(P<0.05).Before the intervention,the levels of osteocalcin,serum calcium,PINP,β-CTX,and 25-hydroxyvitamin D were not significantly different between the two groups(P>0.05).After 12 weeks of intervention,the PN group exhibited higher levels of osteocalcin,serum calcium,and 25-hydroxyvitamin D,as well as lower levels of PINP andβ-CTX,compared to the RD group(P<0.05).In both groups,osteocalcin,serum calcium,and 25-hydroxyvitamin D levels were significantly higher,while PINP andβ-CTX levels were significantly lower after 12 weeks of intervention compared to baseline(P<0.05).CONCLUSION The human BCA-based dietary nutrition regimen plays a crucial role in improving BMD and bone metabolism,with effects that surpass those of conventional nutrition strategies.The findings of this study provide strong evidence for the nutritional management of AD patients. 展开更多
关键词 Alzheimers disease Bone metabolism disorders Human body composition analysis Dietary nutrition Bone homeostasis Dietary management
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A Bayesian multi-model inference methodology for imprecise momentindependent global sensitivity analysis of rock structures
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作者 Akshay Kumar Gaurav Tiwari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期840-859,共20页
Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating du... Traditional global sensitivity analysis(GSA)neglects the epistemic uncertainties associated with the probabilistic characteristics(i.e.type of distribution type and its parameters)of input rock properties emanating due to the small size of datasets while mapping the relative importance of properties to the model response.This paper proposes an augmented Bayesian multi-model inference(BMMI)coupled with GSA methodology(BMMI-GSA)to address this issue by estimating the imprecision in the momentindependent sensitivity indices of rock structures arising from the small size of input data.The methodology employs BMMI to quantify the epistemic uncertainties associated with model type and parameters of input properties.The estimated uncertainties are propagated in estimating imprecision in moment-independent Borgonovo’s indices by employing a reweighting approach on candidate probabilistic models.The proposed methodology is showcased for a rock slope prone to stress-controlled failure in the Himalayan region of India.The proposed methodology was superior to the conventional GSA(neglects all epistemic uncertainties)and Bayesian coupled GSA(B-GSA)(neglects model uncertainty)due to its capability to incorporate the uncertainties in both model type and parameters of properties.Imprecise Borgonovo’s indices estimated via proposed methodology provide the confidence intervals of the sensitivity indices instead of their fixed-point estimates,which makes the user more informed in the data collection efforts.Analyses performed with the varying sample sizes suggested that the uncertainties in sensitivity indices reduce significantly with the increasing sample sizes.The accurate importance ranking of properties was only possible via samples of large sizes.Further,the impact of the prior knowledge in terms of prior ranges and distributions was significant;hence,any related assumption should be made carefully. 展开更多
关键词 Bayesian inference Multi-model inference statistical uncertainty Global sensitivity analysis(GsA) Borgonovo’s indices Limited data
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Transitivity Analysis of the Energy in China’s New Era
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作者 SHAN Ting WANG Yu 《Journal of Literature and Art Studies》 2024年第2期170-176,共7页
At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environme... At present,with the steady development of the global economy,more and more countries begin to pay attention to the impact of ecological environment on economic development and human society,so the ecological environment has become a global issue that cannot be ignored in today’s era.Therefore,from the perspective of the ecological philosophy of Diversity&Harmony as well as Interaction&Co-existence,this paper will conduct ecological discourse analysis on the Energy in China’s New Era based on the transitivity system of systemic-functional grammar,and use the Corpus analysis software UAM Corpus Tool 3.3x to label and make statistics on the transitivity system,aiming to explore the distribution characteristics of the transitivity system in this white paper.Through the transitivity analysis of the white paper,this study helps readers to have a deeper understanding of the positive significance contained in the white paper.To a certain extent,it enables readers at home and abroad to understand China’s stance on energy issues and the positive image of China in energy ecology.It also awaken readers’awareness of environmental protection and acquire good habits of resource conservation to be in harmony between human and nature for sustainable development. 展开更多
关键词 TrANsITIVITY Ecological discourse analysis Energy in China’s new era
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Conceptual Analysis of Self-Management in Patients with Hypertension
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作者 Li Yang Yutian Hao +4 位作者 Liling Zhong Shilin Xu Saiqiong Zhong Yanying Lu Hui Liu 《Journal of Clinical and Nursing Research》 2024年第5期356-368,共13页
Objective:To clarify the concept of self-management in hypertensive patients by analyzing the definition,attributes,and measurement tools through a literature review.Methods:An Internet-based search of the databases w... Objective:To clarify the concept of self-management in hypertensive patients by analyzing the definition,attributes,and measurement tools through a literature review.Methods:An Internet-based search of the databases was conducted using Academic Search Complete,Medical Line,CINAHL,Health Source:Nursing/Scholarly Edition,and Google Scholar.In the search process,keywords or free text were combined by using Boolean operators,with the search terms“self of management”or“self-management,”“concept*analysis”or“concept*definition,”and Walker and Avant’s concept analysis method was used.Results:Analysis of relevant literature summarized the conceptual attributes of self-management in hypertensive patients as the active participation of patients in the treatment process;the presence of interaction provided by patients and health care providers;the use of certain health management tools;and the aim of maintaining and improving the health status and living capacity of hypertensive patients.Conclusion:The concept of self-management for hypertensive patients was clarified,which helps to promote the application of hypertensive self-management in clinical work and improve outcomes and quality of life for patients with hypertension. 展开更多
关键词 HYPErTENsION sELF-MANAGEMENT Concept analysis Walker and Avant’s concept analysis method
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Comparison of R and Excel in the Field of Data Analysis
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作者 Jue Wang 《Journal of Electronic Research and Application》 2024年第3期178-184,共7页
This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and i... This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and its powerful data management and analysis tools make it suitable for handling complex data analysis tasks.It is also highly customizable,allowing users to create custom functions and packages to meet their specific needs.Additionally,R language provides high reproducibility,making it easy to replicate and verify research results,and it has excellent collaboration capabilities,enabling multiple users to work on the same project simultaneously.These advantages make R language a more suitable choice for complex data analysis tasks,particularly in scientific research and business applications.The findings of this study will help people understand that R is not just a language that can handle more data than Excel and demonstrate that r is essential to the field of data analysis.At the same time,it will also help users and organizations make informed decisions regarding their data analysis needs and software preferences. 展开更多
关键词 EXCEL r language Data analysis Open source COMPArE Data management Advantages Disadvantages FUNCTION
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Discourse Analysis of the Belt and Road Initiative From the Perspective of Central Asian Countries: A Case Study of the Republic of Kazakhstan
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作者 CHEN Jia LIU Shumin +1 位作者 FU Da’an SHAO Di 《Journalism and Mass Communication》 2024年第2期96-100,共5页
This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initi... This study employs Norman Fairclough’s Critical Discourse Analysis(CDA)three-dimensional model,using the Republic of Kazakhstan as a case study,to delve into the discourse construction of China’s Belt and Road Initiative(BRI)in Central Asian countries.Through detailed analysis of policy documents,media reports,and public discussions in Central Asian countries,this paper reveals how the BRI constructs specific social practices,discourse events,and textual meanings within these nations.The findings indicate that through this global development strategy,China has not only strengthened its economic ties with Central Asian countries but has also exerted profound influences on political,cultural,and social levels. 展开更多
关键词 Belt and road Initiative Central Asian countries discourse analysis Norman Fairclough’s three-dimensional model
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R-Factor Analysis of Data Based on Population Models Comprising R- and Q-Factors Leads to Biased Loading Estimates
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作者 André Beauducel 《Open Journal of Statistics》 2024年第1期38-54,共17页
Effects of performing an R-factor analysis of observed variables based on population models comprising R- and Q-factors were investigated. Although R-factor analysis of data based on a population model comprising R- a... Effects of performing an R-factor analysis of observed variables based on population models comprising R- and Q-factors were investigated. Although R-factor analysis of data based on a population model comprising R- and Q-factors is possible, this may lead to model error. Accordingly, loading estimates resulting from R-factor analysis of sample data drawn from a population based on a combination of R- and Q-factors will be biased. It was shown in a simulation study that a large amount of Q-factor variance induces an increase in the variation of R-factor loading estimates beyond the chance level. Tests of the multivariate kurtosis of observed variables are proposed as an indicator of possible Q-factor variance in observed variables as a prerequisite for R-factor analysis. 展开更多
关键词 r-Factor analysis Q-Factor analysis Loading Bias Model Error Multivariate Kurtosis
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大学生信息成瘾行为的触发路径与干预策略:基于S-O-R理论视角
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作者 张晨 姜为翰 钱鹏博 《科技情报研究》 2025年第1期118-130,共13页
[目的/意义]文章以大学生为研究对象,探究该群体信息成瘾行为的影响机制,为大学生信息成瘾行为的预防和管理提供价值参考。[方法/过程]引入刺激-机体-反应(S-O-R)理论,利用文献梳理总结大学生信息成瘾过程中的外部刺激,深度剖析机体在... [目的/意义]文章以大学生为研究对象,探究该群体信息成瘾行为的影响机制,为大学生信息成瘾行为的预防和管理提供价值参考。[方法/过程]引入刺激-机体-反应(S-O-R)理论,利用文献梳理总结大学生信息成瘾过程中的外部刺激,深度剖析机体在成瘾过程中产生的认知心理,构建大学生信息成瘾行为理论模型,运用结构方程模型实证分析大学生信息成瘾的触发路径。[结果/结论]研究结果表明,信息过载、间歇性奖励和行为管理会显著正向影响大学生的不确定性回避,进而导致大学生信息成瘾。同时,信息过载也会使大学生产生信息焦虑,信息焦虑显著正向影响大学生信息成瘾行为。面向高等院校、大学生群体和科技企业,提出针对性建议与对策,有助于完善高等院校管理体系,促进学生适应信息化环境,推动高等教育事业更好发展。 展开更多
关键词 信息成瘾 s-O-r理论 结构方程模型 干预策略
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基于S-O-R模型的信息素养教育影响体育行为的中介路经研究
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作者 张婕 王慧琳 《山东体育科技》 2025年第1期9-14,共6页
教育干预是维持长期体育行为的重要因素之一。基于S-O-R模型,从外部刺激和内部转化,探索信息素养教育模式影响体育行为的模型及路径。以信息素养课程学习者为研究对象进行实证研究,发现信息素养教育从体育信息的视角提供的知识支持、技... 教育干预是维持长期体育行为的重要因素之一。基于S-O-R模型,从外部刺激和内部转化,探索信息素养教育模式影响体育行为的模型及路径。以信息素养课程学习者为研究对象进行实证研究,发现信息素养教育从体育信息的视角提供的知识支持、技术支持和环境支持,通过个体感知后内化为参与意愿正向影响体育行为。 展开更多
关键词 s-O-r模型 信息素养教育 体育行为 体育参与意愿 个体感知
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R/S AND WAVELET ANALYSIS ON EVOLUTIONARYPROCESS OF REGIONAL ECONOMIC DISPARITY IN CHINA DURING PAST 50 YEARS 被引量:9
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作者 XUJian-hua LUYan +1 位作者 SUFang-lin AINan-shan 《Chinese Geographical Science》 SCIE CSCD 2004年第3期193-201,共9页
This paper shows the dynamic process of regional disparity of economic development in China in the past 50 years from a new insight by using the rescaled range statistic (R/S) analysis and wavelet analysis of the Thei... This paper shows the dynamic process of regional disparity of economic development in China in the past 50 years from a new insight by using the rescaled range statistic (R/S) analysis and wavelet analysis of the Theil index sequence with different time scales. The main conclusions are: 1) The regional disparity of economic development in China, including the inter-provincial disparity, inter-regional disparity and intra-regional disparity, has existed for many years. Theil index by the comparative price has revealed the true trend for comparative disparity of regional economic development from 1952 to 2000. 2) Decomposition of Theil index indicates that the dynamic trend of comparative inter-provincial disparity in the coastal region is in line with dynamic trend of inter-provincial disparity in the whole China. 3) The R/S analysis results tell us that during 1966-1978, the Hurst exponent H=0.504 approximate to 0.5, which indicates that in that period the evolution of comparative inter-provincial disparity of economic development showed a random characteristic, and in the other periods, i.e. 1952-1965, 1979-1990 and 1991-2000, the Hurst exponent H>0.5, which indicates that in those periods the evolution of the comparative inter-provincial disparity of economic development in China had a long-enduring characteristic. 4) By using wavelet analysis at different time scale, we arrived at a conclusion that the evolutionary process of the disparity of economic development of China is not a simple inverted U shape but a compound of several U shapes. The result tells us that the evolutionary plot of inter-provincial disparity in China follows the inverted U on the whole at the higher scale, 24 ( 16 years). That is to say, the disparity tends to rise in the first stage of economic development, and fall slowly over the peak in the second stage of economic development. However, if we shorten the time scale to 23 ( 8 years), then a link of several U shapes will appear. 展开更多
关键词 China regional economic disparity Theil index r/s analysis wavelet analysis
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Fractal Method for Statistical Analysis Geological Data 被引量:2
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作者 Meng Xianguo Zhao PengdaChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1991年第1期114-119,共6页
This paper establishes the phase space in the light of spacial series data , discusses the fractal structure of geological data in terms of correlated functions and studies the chaos of these data . In addition , it i... This paper establishes the phase space in the light of spacial series data , discusses the fractal structure of geological data in terms of correlated functions and studies the chaos of these data . In addition , it introduces the R/S analysis for time series analysis into spacial series to calculate the structural fractal dimensions of ranges and standard deviation for spacial series data -and to establish the fractal dimension matrix and the procedures in plotting the fractal dimension anomaly diagram with vector distances of fractal dimension . At last , it has examples of its application . 展开更多
关键词 geological data fractal method fractal dimension space series r/s analysis .
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Multi-scale and multi-fractal analysis of pressure fluctuation in slurry bubble column bed reactor 被引量:1
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作者 王兴军 胡立舜 +3 位作者 沈军杰 余志楠 王辅臣 于遵宏 《Journal of Central South University of Technology》 EI 2007年第5期696-700,共5页
The Daubechies second order wavelet was applied to decompose pressure fluctuation signals with the gas flux varying from 0.18 to 0.90 m3/h and the solid mass fraction from 0 to 20% and scales 1?9 detail signals and th... The Daubechies second order wavelet was applied to decompose pressure fluctuation signals with the gas flux varying from 0.18 to 0.90 m3/h and the solid mass fraction from 0 to 20% and scales 1?9 detail signals and the 9th scale approximation signals. The pressure signals were studied by multi-scale and R/S analysis method. Hurst analysis method was applied to analyze multi-fractal characteristics of different scale signals. The results show that the characteristics of mono-fractal under scale 1 and scale 2, and bi-fractal under scale 3?9 are effective in deducing the hydrodynamics in slurry bubbling flow system. The measured pressure signals are decomposed to micro-scale signals, meso-scale signals and macro-scale signals. Micro-scale and macro-scale signals are of mono-fractal characteristics, and meso-scale signals are of bi-fractal characteristics. By analyzing energy distribution of different scale signals,it is shown that pressure fluctuations mainly reflects meso-scale interaction between the particles and the bubble. 展开更多
关键词 pressure fluctuation r/s analysis MULTI-sCALE MULTI-FrACTAL bubble column bed reactor
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Cloning and Sequence Analysis of 16S rRNA and COI Gene in Mitochondrial DNA of Scortum barcoo 被引量:2
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作者 张龙岗 安丽 +2 位作者 董学飒 孟庆磊 付佩胜 《Agricultural Science & Technology》 CAS 2010年第7期176-178,182,共4页
[Objective] The aim was to provide molecular biological basis for the researches on the genetic resources,genetic relationship among species and phyletic evolution of S.barcoo.[Method] PCR amplification and sequencing... [Objective] The aim was to provide molecular biological basis for the researches on the genetic resources,genetic relationship among species and phyletic evolution of S.barcoo.[Method] PCR amplification and sequencing were used to study the 16S rRNA and COI gene fragments.[Result] As for 16S rRNA gene fragments,nucleotide sequences of 791 bp were obtained,and the A,T,G and C contents in this fragment were 31.6%,21.4%,20.4% and 26.7%respectively.As for the COI gene fragments,the size was 631 bp and the A,T,G And C contents were 27.7%,23.6%,29.8% and 18.9% respectively.Among these two gene fragments,the content of GC was lower than AT,and AT/GC of these two fragments was 1.13 and 1.05 respectively.[Conclusion] The genetic characteristics of gene fragments of 16S rRNA and COI of S.barcoo suggested that the variation in the same species was relatively low.The sequences of 16S rRNA gene in three samples the same,while the sequences of COI gene was also the same,indicating that these two gene of S.barcoo were conservative. 展开更多
关键词 scortum barcoo 16s rrNA and COI gene sequence analysis
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基于海德平衡理论的S⁃O⁃R模式在妇科肿瘤病人中应用的临床效果观察
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作者 孙纯 张晓燕 吕亚 《循证护理》 2025年第3期543-547,共5页
目的:分析探讨基于海德平衡理论的S⁃O⁃R模式干预在妇科肿瘤病人中的临床效果。方法:选取2020年5月—2023年7月我院收治的妇科肿瘤病人80例,随机分为对照组和研究组,各40例。对照组实施常规干预,研究组在对照组基础上,实施基于海德平衡... 目的:分析探讨基于海德平衡理论的S⁃O⁃R模式干预在妇科肿瘤病人中的临床效果。方法:选取2020年5月—2023年7月我院收治的妇科肿瘤病人80例,随机分为对照组和研究组,各40例。对照组实施常规干预,研究组在对照组基础上,实施基于海德平衡理论的S⁃O⁃R模式干预。比较两组干预前后心理状态、疾病不确定感、生活质量及并发症发生率。结果:干预后,研究组焦虑抑郁量表中焦虑状态、抑郁状态评分均低于对照组(P<0.001);研究组复杂性、不确定性评分低于对照组(P<0.001);研究组诺丁汉健康量表中精力维度、情感维度、社会活动维度评分均低于对照组(P<0.05);研究组并发症总发生率低于对照组(P<0.05)。结论:妇科肿瘤病人S⁃O⁃R模式干预中引入海德平衡理论可减轻其疾病不确定感,改善心理状态及生活质量,降低并发症发生率。 展开更多
关键词 妇科肿瘤 s⁃O⁃r模式 海德平衡理论 心理状态 疾病不确定感 生活质量 并发症
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Prediction of natural fracture in shale oil reservoir based on R/S analysis and conventional logs
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作者 Haoran XU Wei JU +5 位作者 Xiaobing NIU Shengbin FENG Yuan YOU Hui YANG Sijia LIU Wenbo LUAN 《Frontiers of Earth Science》 SCIE CSCD 2021年第3期705-718,共14页
Investigation into natural fractures is extremely important for the exploration and development of low-permeability reservoirs.Previous studies have proven that abundant oil resources are present in the Upper Triassic... Investigation into natural fractures is extremely important for the exploration and development of low-permeability reservoirs.Previous studies have proven that abundant oil resources are present in the Upper Triassic Yanchang Formation Chang 7 oil-bearing layer of the Ordos Basin,which are accumulated in typical low-permeability shale reservoirs.Natural fractures are important storage spaces and flow pathways for shale oil.In this study,characteristics of natural fractures in the Chang 7 oil-bearing layer are first analyzed.The results indicate that most fractures are shear fractures in the Heshui region,which are characterized by high-angle,unfilled,and ENE-WSW-trending strike.Subsequently,natural fracture distributions in the Yanchang Formation Chang 7 oil-bearing layer of the study area are predicted based on the R/S analysis approach.Logs of AC,CAL,ILD,LL8,and DEN are selected and used for fracture prediction in this study,and the R(n)/S(n)curves of each log are calculated.The quadratic derivatives are calculated to identify the concave points in the R(n)/S(n)curve,indicating the location where natural fracture develops.Considering the difference in sensitivity of each log to natural fracture,gray prediction analysis is used to construct a new parameter,fracture prediction indicator K,to quantitatively predict fracture development.In addition,fracture development among different wells is compared.The results show that parameter K responds well to fracture development.Some minor errors may probably be caused by the heterogeneity of the reservoir,limitation of core range and fracture size,dip angle,filling minerals,etc. 展开更多
关键词 natural fracture prediction shale oil reservoir r/s analysis Chang 7 oil-bearing layer Ordos Basin
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R/S Analysis of China Securities Markets
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作者 华苏 林勇 《Tsinghua Science and Technology》 SCIE EI CAS 2003年第5期537-540,共4页
This paper presents the law of changes of indices and stocks in the Shanghai and Shenzhen Stock Exchanges by using rescaled range analysis in nonlinear time series analysis. The Hurst exponents of the stock indices a... This paper presents the law of changes of indices and stocks in the Shanghai and Shenzhen Stock Exchanges by using rescaled range analysis in nonlinear time series analysis. The Hurst exponents of the stock indices and of all stocks listed in the Shanghai and Shenzhen Stock Exchanges are estimated. The results show that the changes of indices and stocks in the last period have positive impact in the next period in the short run, but this impact disappears for long time. 展开更多
关键词 r/s analysis Hurst exponent efficiency market hypothesis
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved s1 selection method Maize population Genetic gain Comparative analysis
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GENERAL RELIABILITY ANALYSIS FOR TWO DIMENSIONAL SLOPES
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作者 揭敏 邓泽贤 李大海 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第1期36-41,共6页
The reliability analysis, based on the reliability index method, of two dimensional slopes is generalized by taking Sarma′s acceleration as the performance function. That is to say, a general expression of the perfo... The reliability analysis, based on the reliability index method, of two dimensional slopes is generalized by taking Sarma′s acceleration as the performance function. That is to say, a general expression of the performance function is given under various kinds of slice methods, even under various shapes of slice partition, beyond the traditional vertical slice method. A simple example shows explicitly the relationship of four commonly used slice methods in the slope reliability analysis. It is also found that the results of the reliability analysis are basically consistent with those of the stability analysis based on Sarma′s method. 展开更多
关键词 reliability stability analysis two dimen sional slope sarma′s method
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Ecological Models Reveal a Weakened Population Structure, and Distribution Drivers of Osyris lanceolata (Santalaceae) in the Karamoja Sub-Region, Uganda
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作者 Ben Belden Mugula Samuel Kuria Kiboi +6 位作者 James Ireri Kanya Harald Meimberg Manuel Curto Paul Okullo Anthony Egeru Jenipher Biira Salamula Stephen F. Omondi 《Open Journal of Ecology》 2025年第2期153-173,共21页
Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and... Osyris lanceolata is heavily and illegally exploited in East Africa for its essential oils, yet little is known about its population status and ecological requirements. This study examined its population structure and environmental factors influencing its distribution in the semi-arid Karamoja sub-region, Uganda. We surveyed 388 plots (5 m radius) at different altitudes, recording life stages, stem diameters, and regeneration patterns, and analyzed soil samples. Multivariate analyses, including Canonical Correspondence Analysis (CCA), Detrended Correspondence Analysis (DCA), Non-metric Multidimensional Scaling (NMDS), and Multiple Regression Modeling (MRM), identified key environmental factors affecting its distribution. Findings show that O. lanceolata populations in Moroto, Nakapiripirit, and Amudat districts are severely degraded due to overexploitation. The species is primarily regenerating through coppicing rather than seedlings, with an exploitation intensity of 56.6%. Population densities are low, distribution is irregular, and sustainable harvesting is not viable. Soil properties, particularly Ca2+, N, P, K+, Na+, and organic matter, significantly influence its abundance. Conservation efforts should focus on identifying suitable provenances for genetic preservation and plantation establishment. Areas with at least 9 trees per hectare in Moroto, Nakapiripirit, and Amudat could serve as potential sites for ex-situ plantations. Further research should explore how biotic interactions, genetic diversity, and morphology affect oil yield and quality to support restoration, breeding, and domestication initiatives. 展开更多
关键词 Plant Ecology Hemiparasites Edaphic Drivers Ecological Modelling Multivariate analysis Essential Oils r
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