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Climate change and human activities on runoff in northern Shaanxi:Based on Budyko framework analysis
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作者 ZHANG Lin JIANG Xiaohui +1 位作者 XU Fangbing YANG Anle 《Journal of Geographical Sciences》 2025年第5期979-1002,共24页
Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological el... Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological element trends were analyzed using theβ-z-h three-parameter indication method.The Mann-Kendall,Pettitt,moving T,and Yamamoto methods were used to test the mutation point of hydrological elements.The Budyko framework was used to quantitatively assess the impacts of climate change and multiple human activities on runoff reduction.The results showed that(1):Precipitation(PRE),potential evapotranspiration(E0),and temperature(TEM)showed increasing trends;runoff in the Huangfuchuan,Gushanchuan,Kuye River,Tuwei River,Wuding River,Qingjian River,and Yanhe River catchments showed decreasing trends(HFC,GSC,KYR,TWR,WDR,QJR,YR);whereas runoff in the Jialu River(JLR)catchment showed a“V-shaped”trend from 1980 to2020.(2)Runoff was positively correlated with PRE and negatively correlated with E0and the subsurface index(n),with the elasticity coefficients of PRE,E0,and n showing an increasing trend in the change period.(3)Human activities were a key factor in runoff reduction,although the impact of different human activities showed spatial variations.This study provides a scientific foundation for achieving the sustainable development of water resources in mining areas. 展开更多
关键词 hydrological elements trend analysis mutation points Budyko framework attribution analysis mining areas northern Shaanxi
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Financial Capability Analysis of Gree Electric Appliances Based on the Harvard Framework
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作者 Jiaxin Zhang 《Journal of Frontier in Economic and Management Research》 2025年第1期101-122,共22页
This study employs the Harvard analytical framework to evaluate Gree Electric's financial performance across strategy,accounting,finance,and prospects.Results show that Gree leads the industry in profitability and... This study employs the Harvard analytical framework to evaluate Gree Electric's financial performance across strategy,accounting,finance,and prospects.Results show that Gree leads the industry in profitability and long-term debt repayment capacity,supported by strong R&D and cost control from its vertically integrated model.Sustained innovation has generated extensive patents,enabling high-margin premium products.However,Gree faces constraints due to over-reliance on its core air-conditioning business,declining inventory turnover,and slow overseas expansion.Its diversification into new sectors like new energy and smart equipment remains limited,accounting for under 5%of revenue and failing to mitigate core market risks.Operating cash flow volatility further reflects instability in these new ventures.Strategic recommendations include scaling the new energy segment,enhancing overseas localization,and optimizing supply chain finance.The study also suggests that Gree should focus on green,smart technologies and value-added services to strengthen competitive barriers.Future research could incorporate ESG metrics to improve analytical comprehensiveness. 展开更多
关键词 Gree Electric Appliances Harvard analysis framework Financial analysis
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Application Research of Multi-Dimensional Customer Behavior Analysis Model in Precision Marketing
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作者 Shuotong Dong 《Open Journal of Applied Sciences》 2024年第12期3589-3600,共12页
The advent of the digital era has provided unprecedented opportunities for businesses to collect and analyze customer behavior data. Precision marketing, as a key means to improve marketing efficiency, highly depends ... The advent of the digital era has provided unprecedented opportunities for businesses to collect and analyze customer behavior data. Precision marketing, as a key means to improve marketing efficiency, highly depends on a deep understanding of customer behavior. This study proposes a theoretical framework for multi-dimensional customer behavior analysis, aiming to comprehensively capture customer behavioral characteristics in the digital environment. This framework integrates concepts of multi-source data including transaction history, browsing trajectories, social media interactions, and location information, constructing a theoretically more comprehensive customer profile. The research discusses the potential applications of this theoretical framework in precision marketing scenarios such as personalized recommendations, cross-selling, and customer churn prevention. Through analysis, the study points out that multi-dimensional analysis may significantly improve the targeting and theoretical conversion rates of marketing activities. However, the research also explores theoretical challenges that may be faced in the application process, such as data privacy and information overload, and proposes corresponding conceptual coping strategies. This study provides a new theoretical perspective on how businesses can optimize marketing decisions using big data thinking while respecting customer privacy, laying a foundation for future empirical research. 展开更多
关键词 Customer Behavior analysis Precision Marketing multi-dimensional Model Data Theory Personalized Recommendation
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Reliability of multi-dimensional network systems with nodes having stochastic connection ranges
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作者 FU Yuqiang MA Xiaoyang ZHAO Fei 《Journal of Systems Engineering and Electronics》 2025年第4期1017-1023,共7页
This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with... This paper proposes a reliability evaluation model for a multi-dimensional network system,which has potential to be applied to the internet of things or other practical networks.A multi-dimensional network system with one source element and multiple sink elements is considered first.Each element can con-nect with other elements within a stochastic connection ranges.The system is regarded as successful as long as the source ele-ment remains connected with all sink elements.An importance measure is proposed to evaluate the performance of non-source elements.Furthermore,to calculate the system reliability and the element importance measure,a multi-valued decision diagram based approach is structured and its complexity is analyzed.Finally,a numerical example about the signal transfer station system is illustrated to analyze the system reliability and the ele-ment importance measure. 展开更多
关键词 multi-dimensional network multi-valued decision diagram stochastic connection range reliability analysis impor-tance measure.
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Systematic Security Guideline Framework through Intelligently Automated Vulnerability Analysis
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作者 Dahyeon Kim Namgi Kim Junho Ahn 《Computers, Materials & Continua》 SCIE EI 2024年第3期3867-3889,共23页
This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world sof... This research aims to propose a practical framework designed for the automatic analysis of a product’s comprehensive functionality and security vulnerabilities,generating applicable guidelines based on real-world software.The existing analysis of software security vulnerabilities often focuses on specific features or modules.This partial and arbitrary analysis of the security vulnerabilities makes it challenging to comprehend the overall security vulnerabilities of the software.The key novelty lies in overcoming the constraints of partial approaches.The proposed framework utilizes data from various sources to create a comprehensive functionality profile,facilitating the derivation of real-world security guidelines.Security guidelines are dynamically generated by associating functional security vulnerabilities with the latest Common Vulnerabilities and Exposure(CVE)and Common Vulnerability Scoring System(CVSS)scores,resulting in automated guidelines tailored to each product.These guidelines are not only practical but also applicable in real-world software,allowing for prioritized security responses.The proposed framework is applied to virtual private network(VPN)software,wherein a validated Level 2 data flow diagram is generated using the Spoofing,Tampering,Repudiation,Information Disclosure,Denial of Service,and Elevation of privilege(STRIDE)technique with references to various papers and examples from related software.The analysis resulted in the identification of a total of 121 vulnerabilities.The successful implementation and validation demonstrate the framework’s efficacy in generating customized guidelines for entire systems,subsystems,and selected modules. 展开更多
关键词 framework AUTOMATION vulnerability analysis SECURITY GUIDELINES
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Porous covalent organic frameworks-improved solid phase microextraction ambient mass spectrometry for ultrasensitive analysis of tetrabromobisphenol-A analogs 被引量:2
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作者 Wei Gao Min Li +5 位作者 Yun Fa Zongshan Zhao Yaqi Cai Xiangfeng Liang Yongliang Yu Guibin Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第8期3849-3852,共4页
Owing to frequent environmental monitoring of tetrabromobisphenol-A(TBBPA)analogs and their potential ecotoxicological effects on organisms,analysis of trace levels of TBBPA analogs with more non-polar and less water-... Owing to frequent environmental monitoring of tetrabromobisphenol-A(TBBPA)analogs and their potential ecotoxicological effects on organisms,analysis of trace levels of TBBPA analogs with more non-polar and less water-soluble characteristics is of great significance for studying their environmental behaviors and toxic effects.Herein,a fast and sensitive technique is developed for directly detecting aqueous TBBPA analogs,including TBBPA mono(allyl ether)(TBBPA-MAE),TBBPA mono(2,3-dibromopropyl ether)(TBBPAMDBPE),TBBPA mono(2-hydroxyethyl ether)(TBBPA-MHEE)and TBBPA mono(glycidyl ether)(TBBPAMGE),by combining solid phase microextraction(SPME)based on porous covalent organic frameworks(Porous-COFs)with constant flow desorption ionization-mass spectrometry(CFDI-MS).As chromatographic separation is replaced by constant flow desorption,each sample can be analyzed within 7 min.The hierarchical porous structures(microporous,mesoporous and macroporous)of COFs lead to the enhanced mass transfer and the easier accessibility of active sites to TBBPA analogs,so that the extraction efficiency is 2.3-3.6 times higher than pure microporous COFs,and far superior to commercial coatings.The detection limit and quantification limit of this method are 0.1-1 and 0.4-3.2 ng/L,respectively.Ultratrace levels of TBBPA analogs from 5.0 ng/L to 66 ng/L have been successfully detected in river and sea water samples,showing great potential for subsequent studies of their environmental behaviors and toxicological effects. 展开更多
关键词 Environmental analysis Covalent organic frameworks Solid phase microextraction Ambient mass spectrometry TBBPA analogs
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Multimodal Discourse Analysis of Public Service Posters on Low-Carbon Life
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作者 LIU Meng-yao LI Ju-yuan 《Journal of Literature and Art Studies》 2024年第10期847-853,共7页
Low-carbon living represents both a new lifestyle and an environmental responsibility vital for sustainable development,positioning it as a central theme in environmental public service advertisements(PSAs).This resea... Low-carbon living represents both a new lifestyle and an environmental responsibility vital for sustainable development,positioning it as a central theme in environmental public service advertisements(PSAs).This research employs a multimodal discourse analysis approach to examining eight public service posters advocating low-carbon living from Xinhua News Agency,primarily utilizing the visual grammar framework established by Kress and Van Leeuwen.The study explores these posters through three key perspectives:representational meaning,interactive meaning,and compositional meaning.By analyzing the interplay between visual and linguistic modalities,this research contributes to the overall understanding of public service posters and supports the promotion of China’s low-carbon development initiatives. 展开更多
关键词 multimodal discourse analysis visual grammar framework public service posters
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An Analysis Method of Business Application Framework
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作者 He Ke\|qing 1,Fan Hui hua 1,Ying Shi 2 1.Department of Computer Science, Wuhan University, Wuhan 430072, China 2.State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期218-223,共6页
We discuss the evolution of object oriented software development process based on software pattern. For developing mature software framework and component, we advocate to elicit and incorporate software patterns for ... We discuss the evolution of object oriented software development process based on software pattern. For developing mature software framework and component, we advocate to elicit and incorporate software patterns for ensuing quality and reusability of software frameworks. On the analysis base of requirement specification for business application domain, we present analysis method and basic role model of software framework. We also elicit analysis pattern of framework architecture, and design basic role classes and their structure. 展开更多
关键词 object oriented software framework analysis pattern of architecture COMPONENT role model
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Development of the Data Processing and Analysis System Framework for ICF Experiments
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作者 杨冬 虞孝麒 张弛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2872-2874,共3页
An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing... An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing and analysis framework based on the ROOT system have been completed. Software for unfolding soft X-ray spectra has been developed to test the functions of this framework. 展开更多
关键词 initial confinement fusion data processing and analysis object oriented framework ROOT soft X-ray spectra
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Using an Interprofessional Lens to Analyze Serious Adverse Events in a Teaching Hospital: An Analysis with the TeamSTEPPS® Framework
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作者 Katherine Blondon Catherine Chenaud 《Health》 CAS 2022年第12期1199-1209,共11页
This paper explores the contribution of teamwork skills in serious adverse events, using the TeamSTEPPS<sup>&reg;</sup> framework. Adverse events are the undesirable events that are not due to the natu... This paper explores the contribution of teamwork skills in serious adverse events, using the TeamSTEPPS<sup>&reg;</sup> framework. Adverse events are the undesirable events that are not due to the natural course of a disease;they are considered serious when they prolong a hospital stay, lead to a physical disability or to death. Failures in teamwork, particularly with interprofessional teams, can lead to potential risks to patient safety. Using a dataset of de-identified reports of serious adverse events in 2016 in a tertiary teaching hospital, we explored the contribution of teamwork skills according to the TeamSTEPPS<sup>&reg;</sup> framework to these adverse events. We found that 61% of the 41 analyzed events involved failures in teamwork skills, with 80% of these involving communication, 52% in situation monitoring and team structure, 44% in mutual support and 40% in leadership. Sixty-four percent of the events involved more than one teamwork component. Our findings emphasize the need to improve teamwork training in healthcare, focusing not only on communication, but also on other teamwork skills as they often contribute together in adverse events. Future analyses of serious adverse events should include a focus on teamwork competencies, to guide the development of future quality and safety training programs. 展开更多
关键词 Team Collaboration TeamSTEPPS framework Incident analysis Interprofessional Education
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Modified unified co-rotational framework with beam,shell and brick elements for geometrically nonlinear analysis
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作者 Yufei Rong Qin Sun Ke Liang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第4期116-127,I0003,共13页
The co-rotational finite element formulation is an attractive technique extending the capabilities of an existing high performing linear element to geometrically nonlinear analysis.This paper presents a modified co-ro... The co-rotational finite element formulation is an attractive technique extending the capabilities of an existing high performing linear element to geometrically nonlinear analysis.This paper presents a modified co-rotational framework,unified for beam,shell,and brick elements.A unified zero-spin criterion is proposed to specify the local element frame,whose origin is always located at the centroid.Utilizing this criterion,a spin matrix is introduced,and the local frame is invariant to the element nodal ordering.Additionally,the projector matrix is redefined in a more intuitive way,which is the derivative of local co-rotational element frame with respect to the global one.Furthermore,the nodal rotation is obtained with pseudo vector and instantaneous rotation,under a high-order accurate transformation.The resulting formulations are achieved in unified expression and thus a series of linear elements can be embedded into the framework.Several examples are presented to demonstrate the efficiency and accuracy of the proposed framework for large displacement analysis. 展开更多
关键词 Geometrically nonlinear analysis Modified co-rotational framework Unified zero-spin criterion Spin matrix PROJECTOR
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Open-Access Framework for Efficient Object-Oriented Development of Video Analysis Software
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作者 Dimitris K. Iakovidis Dimitris Diamantis 《Journal of Software Engineering and Applications》 2014年第8期730-743,共14页
The increasing use of digital video everyday in a multitude of electronic devices, including mobile phones, tablets and laptops, poses the need for quick development of cross-platform video software. However current a... The increasing use of digital video everyday in a multitude of electronic devices, including mobile phones, tablets and laptops, poses the need for quick development of cross-platform video software. However current approaches to this direction usually require a long learning curve, and their development lacks standardization. This results in software components that are difficult to reuse, and hard to maintain or extend. In order to overcome such issues, we propose a novel object-oriented framework for efficient development of software systems for video analysis. It consists of a set of four abstract components, suitable for the implementation of independent plug-in modules for video acquisition, preprocessing, analysis and output handling. The extensibility of each module can be facilitated by sub-modules specifying additional functionalities. This architecture enables quick responses to changes and re-configurability;thus conforming to the requirements of agile software development practices. Considering the need for platform independency, the proposed Java Video Analysis (JVA) framework is implemented in Java. It is publicly available through the web as open-access software, supported by a growing collection of implemented modules. Its efficiency is empirically validated for the development of a representative video analysis system. 展开更多
关键词 OBJECT-ORIENTED framework EFFICIENT SOFTWARE Development VIDEO analysis Java
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Selecting the Six Sigma Project: A Multi Data Envelopment Analysis Unified Scoring Framework
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作者 Mazen Arafah 《American Journal of Operations Research》 2015年第3期129-150,共22页
The importance of the project selection phase in any six sigma initiative cannot be emphasized enough. The successfulness of the six sigma initiative is affected by successful project selection. Recently, Data Envelop... The importance of the project selection phase in any six sigma initiative cannot be emphasized enough. The successfulness of the six sigma initiative is affected by successful project selection. Recently, Data Envelopment Analysis (DEA) has been proposed as a six sigma project selection tool. However, there exist a number of different DEA formulations which may affect the selection process and the wining project being selected. This work initially applies nine different DEA formulations to several case studies and concludes that different DEA formulations select different wining projects. Also in this work, a Multi-DEA Unified Scoring Framework is proposed to overcome this problem. This framework is applied to several case studies and proved to successfully select the six sigma project with the best performance. The framework is also successful in filtering out some of the projects that have “selective” excellent performance, i.e. projects with excellent performance in some of the DEA formulations and worse performance in others. It is also successful in selecting stable projects;these are projects that perform well in the majority of the DEA formulations, even if it has not been selected as a wining project by any of the DEA formulations. 展开更多
关键词 Data Envelopment analysis Six SIGMA PROJECT Selection Multi-DEA UNIFIED SCORING framework
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Sensitive fluorescence detection of baicalin in biological samples using Eu^(3+)-based metal-organic frameworks
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作者 Hao Zhang Yutong Chen +2 位作者 Runnan Wang Fanxu Meng Dawei Lou 《Journal of Rare Earths》 2025年第8期1703-1710,I0005,共9页
Baicalin,a major flavonoid compound found in Scutellariae radix,is the first SARS-CoV-23CLpro virus inhibitor.Therefore,developing an accurate and reliable strategy to detect baicalin in biological systems is vital.He... Baicalin,a major flavonoid compound found in Scutellariae radix,is the first SARS-CoV-23CLpro virus inhibitor.Therefore,developing an accurate and reliable strategy to detect baicalin in biological systems is vital.Herein,we report the first indolyl-lanthanide metal-organic framework(MOF)materials and their application as baicalin sensors.The results of this study indicate that the new crystal structure has good stability and luminous performance.The detection limits of baicalin in serum and urine are 0.05 and 0.04μmol/L,respectively,suggesting high sensitivity and selectivity.Various background substances present in practical samples,such as anions,cations,and amino acids,do not interfere with the photoluminescence analytical signal of Eu^(3+).We identified that the quenching of the Eu-MOF is due to the inner filter effect,absorption energy competition,and photoinduced electron transfer among the baicalin,ligand,and MOF through powder X-ray diffraction analysis,Fourier transform infrared spectroscopy,luminescence lifetimes,ultraviolet studies,and computational analysis.Thus,we designed a convenient,sensitive,and facile detection method using the Eu-MOF and demonstrate that Eu^(3+)-based materials are promising sensors for baicalin detection in actual serum and urine.Additionally,the prepared Eu-MOF@polyvinyl alcohol composite matrix membrane test film has considerable practical application value for the portable detection of baicalin. 展开更多
关键词 Lanthanide metal-organic frameworks Luminescent materials Rare earths BAICALIN Fluorescent analysis
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A Probe into Economic Regionalization Theory Analysis Framework of Conflicts Between Scale Expansion and Transaction costs
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作者 Deng Xilong 《International Journal of Technology Management》 2014年第6期15-17,共3页
The economic regionalization practice led by China local governments has gradually evolved into chaos. Local governments compete to declare for higher-leveled and large-scaled economic regions to obtain more economic ... The economic regionalization practice led by China local governments has gradually evolved into chaos. Local governments compete to declare for higher-leveled and large-scaled economic regions to obtain more economic resources and policy support in the way of policy game. The author argues that the regionalization chaos is attributed to the reason that the present theoretical support for economic regionalization overemphasizes the economic growth brought about by the economic regionalization but ignores the effect of transaction cost, which leads to constraint loss on the economic regionalization theory analysis framework. Then, the introduction of economic regionalization analysis framework based on the conflicts between scale expansion and transaction costs would establish equilibrium conditions to set up a moderate scale development for economic regions. The author hopes that the acceptance of this framework into the economic regionalization decision-making system would give guidance for making more appropriate regionalization decisions. 展开更多
关键词 Scale expansion Transaction cost Economic regionalization analysis framework
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Financial Analysis of MI’s Company Based on Harvard Analysis Framework
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作者 Jingxian Guo Yuanxi Yang 《Journal of Finance Research》 2021年第2期42-45,共4页
This paper takes the financial statements of MI from 2017to 2019,and uses Harvard analysis framework to analyse the financial situation of MI.The analysis content mainly includes enterprise macro environment,industry ... This paper takes the financial statements of MI from 2017to 2019,and uses Harvard analysis framework to analyse the financial situation of MI.The analysis content mainly includes enterprise macro environment,industry competitive analysis and financial ratio analysis.This paper tried to understand the current situation and development prospect of MI.Based on the analysis of MI’s financial situation under the framework of Harvard,we summarized the existing problems and put forward suggestions. 展开更多
关键词 Harvard Analytical framework Financial ratios Strategic analysis
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Analysis on Discourse Construction of HK Riots between HK Protesters and China's Mainland Media Based on Fairclough’s Three-dimensional Framework of Critical Discourse Analysis
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作者 Jie Li 《教育研究前沿(中英文版)》 2020年第3期159-166,共8页
The Critical Discourse Analysis(CDA)is an interdisciplinary tool in various conditions,which aims to provide a better understanding of sociocultural aspects of texts and accounts of the production of internal structur... The Critical Discourse Analysis(CDA)is an interdisciplinary tool in various conditions,which aims to provide a better understanding of sociocultural aspects of texts and accounts of the production of internal structure,and overall organization of texts as well as to provide a critical dimension in its theoretical and descriptive accounts of texts.Since June last year,HK protests or HK violence have been frequently reported by worldwide media.In this paper,the author aims to find out how the HK protesters and the Mainland media describe the same event based on the three-dimensional framework of CDA.At last,the author concludes that the mainland media generally describe the event as violence and riot while the HK protesters define themselves as warriors striving for more freedom,justice and democracy.Besides,on this event,the Mainland media mainly accuses some western countries of interference into HK affairs,which is undoubtedly of China’s internal affairs,and the media give full support to the HK police in safeguarding the peace and stability of Hong Kong.But from the perspective of HK protesters,they firmly believe that they are using their actions to protect all the people of HK,and they are defending their values such as freedom,democracy and justice.These are two totally different systems of language,and the author also gives its potential reasons in the paper so as to offer some viewpoints in this aspect in combination with the CDA theory. 展开更多
关键词 The Critical Discourse analysis The Three-Dimensional framework The HK Protest The Discourse Construction The HK Riot
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Examining the Burden Reduction Policy for Primary and Secondary School Teachers in China:A Framework Analysis Centered on the Rational Selection of Institutional Doctrine
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作者 Haiying Xu 《Journal of Contemporary Educational Research》 2023年第12期244-247,共4页
The“burden reduction”policy aims to reduce the workload of primary and secondary school teachers to alleviate their burdens.While it has improved the quality of teachers,implementation challenges still exist.This st... The“burden reduction”policy aims to reduce the workload of primary and secondary school teachers to alleviate their burdens.While it has improved the quality of teachers,implementation challenges still exist.This study utilizes rational choice institutionalism and Ostrom’s institutional analysis and development framework to examine the policy.By considering the preferences of the Ministry of Education,local governments,schools,and teachers,it explores interactions and outcomes,identifies challenges,and provides policy suggestions. 展开更多
关键词 Primary and secondary school teachers Reducing burden Rational selection institutional doctrine Institutional analysis and development framework
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Re-Establishing the Merits of Thermal Maturity and Petroleum Generation Multi-Dimensional Modeling with an Arrhenius Equation Using a Single Activation Energy 被引量:4
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作者 David A.Wood 《Journal of Earth Science》 SCIE CAS CSCD 2017年第5期804-834,共31页
Thermal maturation and petroleum generation modeling of shales is essential for suc- cessful exploration and exploitation of conventional and unconventional oil and gas plays. For basin- wide unconventional resource p... Thermal maturation and petroleum generation modeling of shales is essential for suc- cessful exploration and exploitation of conventional and unconventional oil and gas plays. For basin- wide unconventional resource plays such modeling, when well calibrated with direct maturity meas- urements from wells, can characterize and locate production sweet spots for oil, wet gas and dry gas. The transformation of kerogen to petroleum is associated with many chemical reactions, but models typically focus on first-order reactions with rates determined by the Arrhenius Equation. A miscon- ception has been perpetuated for many years that accurate thermal maturity modeling of vitrinite re- flectance using the Arrhenius Equation and a single activation energy, to derive a time-temperature index (~TTIARa), as proposed by Wood (1988), is flawed. This claim was initially made by Sweeney and Burnham (1990) in promoting their "EasyRo" method, and repeated by others. This paper dem- onstrates through detailed multi-dimensional burial and thermal modeling and direct comparison of the ~TTIARR and "EasyRo" methods that this is not the case. The ~TTIA^R method not only provides a very useful and sensitive maturity index, it can reproduce the calculated vitrinite reflectance values derived from models based on multiple activation energies (e.g., "EasyRo"). Through simple expres- sions the ~TTIAaa method can also provide oil and gas transformation factors that can be flexibly scaled and calibrated to match the oil, wet gas and dry gas generation windows. This is achieved in a more-computationally-efficient, flexible and transparent way by the ~TTIARR method than the "EasyRo" method. Analysis indicates that the "EasyRo" method, using twenty activation energies and a constant frequency factor, generates reaction rates and transformation factors that do not realisti- cally model observed kerogen behaviour and transformation factors over geologic time scales. 展开更多
关键词 time-temperature maturity index kerogen activation energies kerogen reaction rates multi-dimensional thermal maturity models petroleum generation versus vitrinite reflectance burial/ thermal history analysis.
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Multi-dimensional blind separation method for STBC systems 被引量:3
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作者 Minggang Luo Liping Li +1 位作者 Guobing Qian Huaguo Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期912-918,共7页
Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by us... Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by using the ordinary independent component analysis (ICA). This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA (MICA) instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms. 展开更多
关键词 multiple input multiple output (MIMO) space-time block code (STBC) multi-dimensional independent component analysis (MICA) blind separation
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