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Discussion on the Application of Enterprise Business Intelligence Data Analysis System
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作者 Ning Yang 《Journal of Electronic Research and Application》 2021年第4期23-26,共4页
Enterprise Business Intelligence(BI)system refers to data mining through the existing database of the enterprise,and data analysis according to customer requirements through comprehensive processing.The data analysis ... Enterprise Business Intelligence(BI)system refers to data mining through the existing database of the enterprise,and data analysis according to customer requirements through comprehensive processing.The data analysis efficiency is high and the operation is convenient.This paper mainly analyzes the application of enterprise BI data analysis system in enterprises. 展开更多
关键词 ENTERPRISE BI data analysis system APPLICATION
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Exploration of University English Teachers’Acceptance and Willingness to Use Learning Management System Data Analysis Tools
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作者 Xiaochao Yao 《Journal of Contemporary Educational Research》 2024年第9期120-128,共9页
This study investigates university English teachers’acceptance and willingness to use learning management system(LMS)data analysis tools in their teaching practices.The research employs a mixed-method approach,combin... This study investigates university English teachers’acceptance and willingness to use learning management system(LMS)data analysis tools in their teaching practices.The research employs a mixed-method approach,combining quantitative surveys and qualitative interviews to understand teachers’perceptions and attitudes,and the factors influencing their adoption of LMS data analysis tools.The findings reveal that perceived usefulness,perceived ease of use,technical literacy,organizational support,and data privacy concerns significantly impact teachers’willingness to use these tools.Based on these insights,the study offers practical recommendations for educational institutions to enhance the effective adoption of LMS data analysis tools in English language teaching. 展开更多
关键词 Learning management system data analysis tools Technology acceptance University English teachers Educational technology data privacy concerns
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Quantitative Analysis of Seeing with Height and Time at Muztagh-Ata Site Based on ERA5 Database
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作者 Xiao-Qi Wu Cun-Ying Xiao +3 位作者 Ali Esamdin Jing Xu Ze-Wei Wang Luo Xiao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期87-95,共9页
Seeing is an important index to evaluate the quality of an astronomical site.To estimate seeing at the Muztagh-Ata site with height and time quantitatively,the European Centre for Medium-Range Weather Forecasts reanal... Seeing is an important index to evaluate the quality of an astronomical site.To estimate seeing at the Muztagh-Ata site with height and time quantitatively,the European Centre for Medium-Range Weather Forecasts reanalysis database(ERA5)is used.Seeing calculated from ERA5 is compared consistently with the Differential Image Motion Monitor seeing at the height of 12 m.Results show that seeing decays exponentially with height at the Muztagh-Ata site.Seeing decays the fastest in fall in 2021 and most slowly with height in summer.The seeing condition is better in fall than in summer.The median value of seeing at 12 m is 0.89 arcsec,the maximum value is1.21 arcsec in August and the minimum is 0.66 arcsec in October.The median value of seeing at 12 m is 0.72arcsec in the nighttime and 1.08 arcsec in the daytime.Seeing is a combination of annual and about biannual variations with the same phase as temperature and wind speed indicating that seeing variation with time is influenced by temperature and wind speed.The Richardson number Ri is used to analyze the atmospheric stability and the variations of seeing are consistent with Ri between layers.These quantitative results can provide an important reference for a telescopic observation strategy. 展开更多
关键词 site testing atmospheric effects methods:data analysis telescopes EARTH
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Study of inter-well interference in shale gas reservoirs by a robust production data analysis method based on deconvolution
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作者 Wen-Chao Liu Cheng-Cheng Qiao +5 位作者 Ping Wang Wen-Song Huang Xiang-Wen Kong Yu-Ping Sun He-Dong Sun Yue-Peng Jia 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2502-2519,共18页
In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering,this study proposes a robust production data analysis method based on deconvolut... In order to overcome the defects that the analysis of multi-well typical curves of shale gas reservoirs is rarely applied to engineering,this study proposes a robust production data analysis method based on deconvolution,which is used for multi-well inter-well interference research.In this study,a multi-well conceptual trilinear seepage model for multi-stage fractured horizontal wells was established,and its Laplace solutions under two different outer boundary conditions were obtained.Then,an improved pressure deconvolution algorithm was used to normalize the scattered production data.Furthermore,the typical curve fitting was carried out using the production data and the seepage model solution.Finally,some reservoir parameters and fracturing parameters were interpreted,and the intensity of inter-well interference was compared.The effectiveness of the method was verified by analyzing the production dynamic data of six shale gas wells in Duvernay area.The results showed that the fitting effect of typical curves was greatly improved due to the mutual restriction between deconvolution calculation parameter debugging and seepage model parameter debugging.Besides,by using the morphological characteristics of the log-log typical curves and the time corresponding to the intersection point of the log-log typical curves of two models under different outer boundary conditions,the strength of the interference between wells on the same well platform was well judged.This work can provide a reference for the optimization of well spacing and hydraulic fracturing measures for shale gas wells. 展开更多
关键词 Shale gas Inter-well interference DECONVOLUTION Production data analysis Typical curves Multi-stage fractured horizontal well
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Data-driven analysis of chemicals,proteins and pathways associated with peanut allergy:from molecular networking to biological interpretation
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作者 Emmanuel Kemmler Julian Braun +5 位作者 Florent Fauchère Sabine Dölle-Bierke Kirsten Beyer Robert Preissner Margitta Worm Priyanka Banerjee 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1322-1335,共14页
Peanut allergy is majorly related to severe food induced allergic reactions.Several food including cow's milk,hen's eggs,soy,wheat,peanuts,tree nuts(walnuts,hazelnuts,almonds,cashews,pecans and pistachios),fis... Peanut allergy is majorly related to severe food induced allergic reactions.Several food including cow's milk,hen's eggs,soy,wheat,peanuts,tree nuts(walnuts,hazelnuts,almonds,cashews,pecans and pistachios),fish and shellfish are responsible for more than 90%of food allergies.Here,we provide promising insights using a large-scale data-driven analysis,comparing the mechanistic feature and biological relevance of different ingredients presents in peanuts,tree nuts(walnuts,almonds,cashews,pecans and pistachios)and soybean.Additionally,we have analysed the chemical compositions of peanuts in different processed form raw,boiled and dry-roasted.Using the data-driven approach we are able to generate new hypotheses to explain why nuclear receptors like the peroxisome proliferator-activated receptors(PPARs)and its isoform and their interaction with dietary lipids may have significant effect on allergic response.The results obtained from this study will direct future experimeantal and clinical studies to understand the role of dietary lipids and PPARisoforms to exert pro-inflammatory or anti-inflammatory functions on cells of the innate immunity and influence antigen presentation to the cells of the adaptive immunity. 展开更多
关键词 Allergy informatics Knowledge-graph data analysis Food allergy Peroxisome proliferator-activated receptors Fatty acids
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A novel medical image data protection scheme for smart healthcare system
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作者 Mujeeb Ur Rehman Arslan Shafique +6 位作者 Muhammad Shahbaz Khan Maha Driss Wadii Boulila Yazeed Yasin Ghadi Suresh Babu Changalasetty Majed Alhaisoni Jawad Ahmad 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期821-836,共16页
The Internet of Multimedia Things(IoMT)refers to a network of interconnected multimedia devices that communicate with each other over the Internet.Recently,smart healthcare has emerged as a significant application of ... The Internet of Multimedia Things(IoMT)refers to a network of interconnected multimedia devices that communicate with each other over the Internet.Recently,smart healthcare has emerged as a significant application of the IoMT,particularly in the context of knowledge‐based learning systems.Smart healthcare systems leverage knowledge‐based learning to become more context‐aware,adaptable,and auditable while maintain-ing the ability to learn from historical data.In smart healthcare systems,devices capture images,such as X‐rays,Magnetic Resonance Imaging.The security and integrity of these images are crucial for the databases used in knowledge‐based learning systems to foster structured decision‐making and enhance the learning abilities of AI.Moreover,in knowledge‐driven systems,the storage and transmission of HD medical images exert a burden on the limited bandwidth of the communication channel,leading to data trans-mission delays.To address the security and latency concerns,this paper presents a lightweight medical image encryption scheme utilising bit‐plane decomposition and chaos theory.The results of the experiment yield entropy,energy,and correlation values of 7.999,0.0156,and 0.0001,respectively.This validates the effectiveness of the encryption system proposed in this paper,which offers high‐quality encryption,a large key space,key sensitivity,and resistance to statistical attacks. 展开更多
关键词 data analysis medical image processing SECURITY
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Enhancing Data Analysis and Automation: Integrating Python with Microsoft Excel for Non-Programmers
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作者 Osama Magdy Ali Mohamed Breik +2 位作者 Tarek Aly Atef Tayh Nour El-Din Raslan Mervat Gheith 《Journal of Software Engineering and Applications》 2024年第6期530-540,共11页
Microsoft Excel is essential for the End-User Approach (EUA), offering versatility in data organization, analysis, and visualization, as well as widespread accessibility. It fosters collaboration and informed decision... Microsoft Excel is essential for the End-User Approach (EUA), offering versatility in data organization, analysis, and visualization, as well as widespread accessibility. It fosters collaboration and informed decision-making across diverse domains. Conversely, Python is indispensable for professional programming due to its versatility, readability, extensive libraries, and robust community support. It enables efficient development, advanced data analysis, data mining, and automation, catering to diverse industries and applications. However, one primary issue when using Microsoft Excel with Python libraries is compatibility and interoperability. While Excel is a widely used tool for data storage and analysis, it may not seamlessly integrate with Python libraries, leading to challenges in reading and writing data, especially in complex or large datasets. Additionally, manipulating Excel files with Python may not always preserve formatting or formulas accurately, potentially affecting data integrity. Moreover, dependency on Excel’s graphical user interface (GUI) for automation can limit scalability and reproducibility compared to Python’s scripting capabilities. This paper covers the integration solution of empowering non-programmers to leverage Python’s capabilities within the familiar Excel environment. This enables users to perform advanced data analysis and automation tasks without requiring extensive programming knowledge. Based on Soliciting feedback from non-programmers who have tested the integration solution, the case study shows how the solution evaluates the ease of implementation, performance, and compatibility of Python with Excel versions. 展开更多
关键词 PYTHON End-User Approach Microsoft Excel data analysis Integration SPREADSHEET PROGRAMMING data Visualization
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Design and Implementation of Log Data Analysis Management System Based on Hadoop 被引量:2
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作者 Dunhong Yao Yu Chen 《Journal of Information Hiding and Privacy Protection》 2020年第2期59-65,共7页
With the rapid development of the Internet,many enterprises have launched their network platforms.When users browse,search,and click the products of these platforms,most platforms will keep records of these network be... With the rapid development of the Internet,many enterprises have launched their network platforms.When users browse,search,and click the products of these platforms,most platforms will keep records of these network behaviors,these records are often heterogeneous,and it is called log data.To effectively to analyze and manage these heterogeneous log data,so that enterprises can grasp the behavior characteristics of their platform users in time,to realize targeted recommendation of users,increase the sales volume of enterprises’products,and accelerate the development of enterprises.Firstly,we follow the process of big data collection,storage,analysis,and visualization to design the system,then,we adopt HDFS storage technology,Yarn resource management technology,and gink load balancing technology to build a Hadoop cluster to process the log data,and adopt MapReduce processing technology and data warehouse hive technology analyze the log data to obtain the results.Finally,the obtained results are displayed visually,and a log data analysis system is successfully constructed.It has been proved by practice that the system effectively realizes the collection,analysis and visualization of log data,and can accurately realize the recommendation of products by enterprises.The system is stable and effective. 展开更多
关键词 Log data HADOOP data analysis data visualization
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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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Research on the prediction method for fluvial-phase sandbody connectivity based on big data analysis--a case study of Bohai a oilfield
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作者 Cai Li Fei Ma +1 位作者 Yuxiu Wang Delong Zhang 《Artificial Intelligence in Geosciences》 2024年第1期359-366,共8页
The connectivity of sandbodies is a key constraint to the exploration effectiveness of Bohai A Oilfield.Conventional connectivity studies often use methods such as seismic attribute fusion,while the development of con... The connectivity of sandbodies is a key constraint to the exploration effectiveness of Bohai A Oilfield.Conventional connectivity studies often use methods such as seismic attribute fusion,while the development of contiguous composite sandbodies in this area makes it challenging to characterize connectivity changes with conventional seismic attributes.Aiming at the above problem in the Bohai A Oilfield,this study proposes a big data analysis method based on the Deep Forest algorithm to predict the sandbody connectivity.Firstly,by compiling the abundant exploration and development sandbodies data in the study area,typical sandbodies with reliable connectivity were selected.Then,sensitive seismic attribute were extracted to obtain training samples.Finally,based on the Deep Forest algorithm,mapping model between attribute combinations and sandbody connectivity was established through machine learning.This method achieves the first quantitative determination of the connectivity for continuous composite sandbodies in the Bohai Oilfield.Compared with conventional connectivity discrimination methods such as high-resolution processing and seismic attribute analysis,this method can combine the sandbody characteristics of the study area in the process of machine learning,and jointly judge connectivity by combining multiple seismic attributes.The study results show that this method has high accuracy and timeliness in predicting connectivity for continuous composite sandbodies.Applied to the Bohai A Oilfield,it successfully identified multiple sandbody connectivity relationships and provided strong support for the subsequent exploration potential assessment and well placement optimization.This method also provides a new idea and method for studying sandbody connectivity under similar complex geological conditions. 展开更多
关键词 Continuous sandbody Connectivity prediction Big data analysis Deep forest Machine learning
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Effectiveness of the Global Banking System in 2010: A Data Envelopment Analysis Approach
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作者 Ngo Dang-Thanh 《Chinese Business Review》 2011年第11期961-973,共13页
The current crisis has revealed the weaknesses of the global financial in general and its banking system in particular and puts forward a requirement for assessing the effectiveness and stability of the banking sector... The current crisis has revealed the weaknesses of the global financial in general and its banking system in particular and puts forward a requirement for assessing the effectiveness and stability of the banking sectors across countries. Based on available data from 64 countries over the world, the author tried to evaluate the effectiveness of the banking sectors in those countries through the view point of the data envelopment analysis approach to define how the global banking systems is under the effect of the current crisis. Findings from the research showed that banking systems in advanced economies are still more effective than in developing countries. Moreover, it explained the effect of the current financial crisis, the role of public finance (and the government), and the development of the (privately) commercial banks to the effectiveness of the banking sectors. The research also explained some determinants that can affect the effectiveness of the banking system, including inflation, bank concentration, and level of economic development. 展开更多
关键词 data envelopment analysis EFFECTIVENESS EFFICIENCY BANKING cross countries
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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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Systematic Review of Graphical Visual Methods in Honeypot Attack Data Analysis
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作者 Gbenga Ikuomenisan Yasser Morgan 《Journal of Information Security》 2022年第4期210-243,共34页
Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabili... Mitigating increasing cyberattack incidents may require strategies such as reinforcing organizations’ networks with Honeypots and effectively analyzing attack traffic for detection of zero-day attacks and vulnerabilities. To effectively detect and mitigate cyberattacks, both computerized and visual analyses are typically required. However, most security analysts are not adequately trained in visualization principles and/or methods, which is required for effective visual perception of useful attack information hidden in attack data. Additionally, Honeypot has proven useful in cyberattack research, but no studies have comprehensively investigated visualization practices in the field. In this paper, we reviewed visualization practices and methods commonly used in the discovery and communication of attack patterns based on Honeypot network traffic data. Using the PRISMA methodology, we identified and screened 218 papers and evaluated only 37 papers having a high impact. Most Honeypot papers conducted summary statistics of Honeypot data based on static data metrics such as IP address, port, and packet size. They visually analyzed Honeypot attack data using simple graphical methods (such as line, bar, and pie charts) that tend to hide useful attack information. Furthermore, only a few papers conducted extended attack analysis, and commonly visualized attack data using scatter and linear plots. Papers rarely included simple yet sophisticated graphical methods, such as box plots and histograms, which allow for critical evaluation of analysis results. While a significant number of automated visualization tools have incorporated visualization standards by default, the construction of effective and expressive graphical methods for easy pattern discovery and explainable insights still requires applied knowledge and skill of visualization principles and tools, and occasionally, an interdisciplinary collaboration with peers. We, therefore, suggest the need, going forward, for non-classical graphical methods for visualizing attack patterns and communicating analysis results. We also recommend training investigators in visualization principles and standards for effective visual perception and presentation. 展开更多
关键词 Honeypot data analysis Network Intrusion Detection Visualization and Visual analysis Graphical Methods and Perception systematic Literature Review
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Seismic data analysis based on spatial subsets 被引量:2
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作者 蔡希玲 刘学伟 +2 位作者 李虹 钱宇明 吕英梅 《Applied Geophysics》 SCIE CSCD 2009年第4期384-392,395,共10页
There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from ... There are some limitations when we apply conventional methods to analyze the massive amounts of seismic data acquired with high-density spatial sampling since processors usually obtain the properties of raw data from common shot gathers or other datasets located at certain points or along lines. We propose a novel method in this paper to observe seismic data on time slices from spatial subsets. The composition of a spatial subset and the unique character of orthogonal or oblique subsets are described and pre-stack subsets are shown by 3D visualization. In seismic data processing, spatial subsets can be used for the following aspects: (1) to check the trace distribution uniformity and regularity; (2) to observe the main features of ground-roll and linear noise; (3) to find abnormal traces from slices of datasets; and (4) to QC the results of pre-stack noise attenuation. The field data application shows that seismic data analysis in spatial subsets is an effective method that may lead to a better discrimination among various wavefields and help us obtain more information. 展开更多
关键词 spatial subset 3D visualization high density sampling noise attenuation data analysis
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Advanced Data Collection and Analysis in Data‑Driven Manufacturing Process 被引量:11
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作者 Ke Xu Yingguang Li +4 位作者 Changqing Liu Xu Liu Xiaozhong Hao James Gao Paul G.Maropoulos 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第3期32-52,共21页
The rapidly increasing demand and complexity of manufacturing process potentiates the usage of manufacturing data with the highest priority to achieve precise analyze and control,rather than using simplified physical ... The rapidly increasing demand and complexity of manufacturing process potentiates the usage of manufacturing data with the highest priority to achieve precise analyze and control,rather than using simplified physical models and human expertise.In the era of data-driven manufacturing,the explosion of data amount revolutionized how data is collected and analyzed.This paper overviews the advance of technologies developed for in-process manufacturing data collection and analysis.It can be concluded that groundbreaking sensoring technology to facilitate direct measurement is one important leading trend for advanced data collection,due to the complexity and uncertainty during indirect measurement.On the other hand,physical model-based data analysis contains inevitable simplifications and sometimes ill-posed solutions due to the limited capacity of describing complex manufacturing process.Machine learning,especially deep learning approach has great potential for making better decisions to automate the process when fed with abundant data,while trending data-driven manufacturing approaches succeeded by using limited data to achieve similar or even better decisions.And these trends can demonstrated be by analyzing some typical applications of manufacturing process. 展开更多
关键词 data-driven manufacturing Intelligent manufacturing Process monitoring data analysis Machine learning
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Frame Work of Data Envelopment Analysis—A Model to Evaluate the Environmental Efficiency of China'S Industrial Sectors 被引量:24
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作者 TAO ZHANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第1期8-13,共6页
Objective To evaluate the environmental and technical efficiencies of China's industrial sectors and provide appropriate advice for policy makers in the context of rapid economic growth and concurrent serious environ... Objective To evaluate the environmental and technical efficiencies of China's industrial sectors and provide appropriate advice for policy makers in the context of rapid economic growth and concurrent serious environmental damages caused by industrial pollutants. Methods A data of envelopment analysis (DEA) framework crediting both reduction of pollution outputs and expansion of good outputs was designed as a model to compute environmental efficiency of China's regional industrial systems. Results As shown by the geometric mean of environmental efficiency, if other inputs were made constant and good outputs were not to be improved, the air pollution outputs would have the potential to be decreased by about 60% in the whole China. Conclusion Both environmental and technical efficiencies have the potential to be greatly improved in China, which may provide some advice for policy-makers. 展开更多
关键词 Technical efficiency Environmental efficiency Directional distance function Technical-environmentalefficiency data of envelopment analysis China
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Fuzzy data envelopment analysis approach based on sample decision making units 被引量:11
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作者 Muren Zhanxin Ma Wei Cui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期399-407,共9页
The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs ty... The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs typically have some levels of fuzziness. To analyze a decision making unit (DMU) with fuzzy input/output data, previous studies provided the fuzzy DEA model and proposed an associated evaluating approach. Nonetheless, numerous deficiencies must still be improved, including the α- cut approaches, types of fuzzy numbers, and ranking techniques. Moreover, a fuzzy sample DMU still cannot be evaluated for the Fuzzy DEA model. Therefore, this paper proposes a fuzzy DEA model based on sample decision making unit (FSDEA). Five eval- uation approaches and the related algorithm and ranking methods are provided to test the fuzzy sample DMU of the FSDEA model. A numerical experiment is used to demonstrate and compare the results with those obtained using alternative approaches. 展开更多
关键词 fuzzy mathematical programming sample decision making unit fuzzy data envelopment analysis EFFICIENCY α-cut.
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Efficiency assessment of coal mine safety input by data envelopment analysis 被引量:22
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作者 TONG Lei DING Ri-jia 《Journal of China University of Mining and Technology》 EI 2008年第1期88-92,共5页
In recent years improper allocation of safety input has prevailed in coal mines in China, which resulted in the frequent accidents in coal mining operation. A comprehensive assessment of the input efficiency of coal m... In recent years improper allocation of safety input has prevailed in coal mines in China, which resulted in the frequent accidents in coal mining operation. A comprehensive assessment of the input efficiency of coal mine safety should lead to improved efficiency in the use of funds and management resources. This helps government and enterprise managers better understand how safety inputs are used and to optimize allocation of resources. Study on coal mine's efficiency assessment of safety input was con- ducted in this paper. A C^2R model with non-Archimedean infinitesimal vector based on output is established after consideration of the input characteristics and the model properties. An assessment of an operating mine was done using a specific set of input and output criteria. It is found that the safety input was efficient in 2002 and 2005 and was weakly efficient in 2003. However, the efficiency was relatively low in both 2001 and 2004. The safety input resources can be optimized and adjusted by means of projection theory. Such analysis shows that, on average in 2001 and 2004, 45% of the expended funds could have been saved. Likewise, 10% of the safety management and technical staff could have been eliminated and working hours devoted to safety could have been reduced by 12%. These conditions could have Riven the same results. 展开更多
关键词 safety input coal mining enterprise efficiency assessment data envelopment analysis (DEA)
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Analysis of the wide area differential correction for BeiDou global satellite navigation system 被引量:4
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作者 Ran Li Yue-Ling Cao +6 位作者 Xiao-Gong Hu Cheng-Pan Tang Shan-Shi Zhou Xin Meng Li Liu Ran-Ran Su Zhi-Qiao Chang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第11期17-28,共12页
The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orb... The regional BeiDou Satellite System, or BDS2, broadcasts a differential correction as Equivalent Satellite Clock Correction to correct both orbit and satellite clock errors. For the global BDS, or BDS3, satellite orbit and clock corrections conforming with RTCA standards will be broadcast to authorized users. The hybrid constellation and regional monitoring network pose challenges for the high precision separation of orbit and satellite clock corrections. Three correction models of kinematic,dynamic and Two-way Satellite Time Frequency Transfer(TWSTFT)-based dynamic were studied to estimate the satellite orbit and clock corrections. The correction accuracy of the three models is compared and analyzed based on the BDS observation data. Results show that the accuracies(root mean square, RMS) of dual-frequency real-time positioning for the three models are about 1.76 m, 1.78 m and 2.08 m respectively, which are comparable with the performance of WAAS and EGNOS. With dynamic corrections, the precision of Precise Point Positioning(PPP) experiments may reach about 23 cm after convergence. 展开更多
关键词 celestial mechanics methods: data analysis space vehicles
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A Quantized Kernel Least Mean Square Scheme with Entropy-Guided Learning for Intelligent Data Analysis 被引量:5
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作者 Xiong Luo Jing Deng +3 位作者 Ji Liu Weiping Wang Xiaojuan Ban Jenq-Haur Wang 《China Communications》 SCIE CSCD 2017年第7期127-136,共10页
Quantized kernel least mean square(QKLMS) algorithm is an effective nonlinear adaptive online learning algorithm with good performance in constraining the growth of network size through the use of quantization for inp... Quantized kernel least mean square(QKLMS) algorithm is an effective nonlinear adaptive online learning algorithm with good performance in constraining the growth of network size through the use of quantization for input space. It can serve as a powerful tool to perform complex computing for network service and application. With the purpose of compressing the input to further improve learning performance, this article proposes a novel QKLMS with entropy-guided learning, called EQ-KLMS. Under the consecutive square entropy learning framework, the basic idea of entropy-guided learning technique is to measure the uncertainty of the input vectors used for QKLMS, and delete those data with larger uncertainty, which are insignificant or easy to cause learning errors. Then, the dataset is compressed. Consequently, by using square entropy, the learning performance of proposed EQ-KLMS is improved with high precision and low computational cost. The proposed EQ-KLMS is validated using a weather-related dataset, and the results demonstrate the desirable performance of our scheme. 展开更多
关键词 quantized kernel least mean square (QKLMS) consecutive square entropy data analysis
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