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Opto-mechanical-thermal integration analysis of Doppler asymmetric spatial heterodyne interferometer
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作者 WANG Jin-jiang JIANG Lun +3 位作者 TONG Shou-feng PEI Hui-yi CUI Yong GUO Ming-hang 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第6期1489-1511,共23页
In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation betw... In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications. 展开更多
关键词 Doppler asymmetric spatial heterodyne interferometer interference module imaging optical system opto-mechanical thermal integration analysis phase error temperature control
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Analysis of Traffic Accidents Based on the Integration Model
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作者 Yanshun Ma Yi Shi +2 位作者 Yihang Song Chenxiao Wu Yuanzhi Liu 《Journal of Electronic Research and Application》 2024年第1期51-59,共9页
To enhance the safety of road traffic operations,this paper proposed a model based on stacking integrated learning utilizing American road traffic accident statistics.Initially,the process involved data cleaning,trans... To enhance the safety of road traffic operations,this paper proposed a model based on stacking integrated learning utilizing American road traffic accident statistics.Initially,the process involved data cleaning,transformation,and normalization.Subsequently,various classification models were constructed,including logistic regression,k-nearest neighbors,gradient boosting,decision trees,AdaBoost,and extra trees models.Evaluation metrics such as accuracy,precision,recall,F1 score,and Hamming loss were employed.Upon analysis,the passive-aggressive classifier model exhibited superior comprehensive indices compared to other models.Based on the model’s output results,an in-depth examination of the factors influencing traffic accidents was conducted.Additionally,measures and suggestions aimed at reducing the incidence of severe traffic accidents were presented.These findings served as a valuable reference for mitigating the occurrence of traffic accidents. 展开更多
关键词 Stacking integrated learning Data analysis Traffic safety
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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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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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Performance Analysis and Optimization of Energy Harvesting Modulation for Multi-User Integrated Data and Energy Transfer
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作者 Yizhe Zhao Yanliang Wu +1 位作者 Jie Hu Kun Yang 《China Communications》 SCIE CSCD 2024年第1期148-162,共15页
Integrated data and energy transfer(IDET)enables the electromagnetic waves to transmit wireless energy at the same time of data delivery for lowpower devices.In this paper,an energy harvesting modulation(EHM)assisted ... Integrated data and energy transfer(IDET)enables the electromagnetic waves to transmit wireless energy at the same time of data delivery for lowpower devices.In this paper,an energy harvesting modulation(EHM)assisted multi-user IDET system is studied,where all the received signals at the users are exploited for energy harvesting without the degradation of wireless data transfer(WDT)performance.The joint IDET performance is then analysed theoretically by conceiving a practical time-dependent wireless channel.With the aid of the AO based algorithm,the average effective data rate among users are maximized by ensuring the BER and the wireless energy transfer(WET)performance.Simulation results validate and evaluate the IDET performance of the EHM assisted system,which also demonstrates that the optimal number of user clusters and IDET time slots should be allocated,in order to improve the WET and WDT performance. 展开更多
关键词 energy harvesting modulation(EHM) integrated data and energy transfer(IDET) performance analysis wireless data transfer(WDT) wireless energy transfer(WET)
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Integrating Virtual Reality and Energy Analysis with BIM to Optimize Window-to-Wall Ratio and Building’s Orientation for Age-in-Place Design at the Conceptual Stage
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作者 Vafa Rostamiasl Ahmad Jrade 《Open Journal of Civil Engineering》 2024年第3期305-333,共29页
This study unfolds an innovative approach aiming to address the critical role of building design in global energy consumption, focusing on optimizing the Window-to-Wall Ratio (WWR), since buildings account for approxi... This study unfolds an innovative approach aiming to address the critical role of building design in global energy consumption, focusing on optimizing the Window-to-Wall Ratio (WWR), since buildings account for approximately 30% of total energy consumed worldwide. The greatest contributors to energy expenditure in buildings are internal artificial lighting and heating and cooling systems. The WWR, determined by the proportion of the building’s glazed area to its wall area, is a significant factor influencing energy efficiency and minimizing energy load. This study introduces the development of a semi-automated computer model designed to offer a real-time, interactive simulation environment, fostering improving communication and engagement between designers and owners. The said model serves to optimize both the WWR and building orientation to align with occupants’ needs and expectations, subsequently reducing annual energy consumption and enhancing the overall building energy performance. The integrated model incorporates Building Information Modeling (BIM), Virtual Reality (VR), and Energy Analysis tools deployed at the conceptual design stage, allowing for the amalgamation of owners’ inputs in the design process and facilitating the creation of more realistic and effective design strategies. 展开更多
关键词 Building Information Modeling (BIM) Virtual Reality (VR) Game Engine Energy analysis Window-to-Wall Ratio Building Orientation Computer integration and Automation
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Application of Choquet Integral-Importance-Performance Analysis and TOPSIS Methods in Approaching the Preference Factors of Calligraphy and Seal Engraving Imagery
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作者 Yu Hsuan Chang Jiann Sheng Jiang Min Min Lin 《Journal of Contemporary Educational Research》 2024年第5期276-288,共13页
Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Call... Classical Chinese characters,presented through calligraphy,seal engraving,or painting,can exhibit different aesthetics and essences of Chinese characters,making them the most important asset of the Chinese people.Calligraphy and seal engraving,as two closely related systems in traditional Chinese art,have developed through the ages.Due to changes in lifestyle and advancements in modern technology,their original functions of daily writing and verification have gradually diminished.Instead,they have increasingly played a significant role in commercial art.This study utilizes the Evaluation Grid Method(EGM)and the Analytic Hierarchy Process(AHP)to research the key preference factors in the application of calligraphy and seal engraving imagery.Different from the traditional 5-point equal interval semantic questionnaire,this study employs a non-equal interval semantic questionnaire with a golden ratio scale,distinguishing the importance ratio of adjacent semantic meanings and highlighting the weighted emphasis on visual aesthetics.Additionally,the study uses Importance-Performance Analysis(IPA)and Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)to obtain the key preference sequence of calligraphy and seal engraving culture.Plus,the Choquet integral comprehensive evaluation is used as a reference for IPA comparison.It is hoped that this study can provide cultural imagery references and research methods,injecting further creativity into industrial design. 展开更多
关键词 Evaluation Grid Method Analytic Hierarchy Process CALLIGRAPHY Seal engraving Importance-Performance analysis Choquet integral TOPSIS
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Co-integration Analysis on the Relationship between Methane Energy Development and Economic Growth in the City of Huixian 被引量:3
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作者 LIU Xiao-ling ZHENG Xun-gang 《Asian Agricultural Research》 2011年第7期35-38,共4页
Based on the statistical data of Huixian from 1992 to 2010, we analyze the long-term and short-term relationship between Huixian's methane energy development and GDP by using co-integration test and error correcti... Based on the statistical data of Huixian from 1992 to 2010, we analyze the long-term and short-term relationship between Huixian's methane energy development and GDP by using co-integration test and error correction model. The empirical results show that there is a long-term equilibrium relationship between methane energy and GDP in the city of Huixian, and which is the one-way Granger causality of methane and GDP. In conclusion, the paper puts forward some steps about spurring economic growth, methane development and utilization in Huixian. 展开更多
关键词 Methane energy Economic growth co-integration analysis China
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An Empirical Application of User-Guided Program Analysis
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作者 Wang Jigang Cheng Shengyu +1 位作者 Cao Jicheng He Meihua 《China Communications》 SCIE CSCD 2024年第7期325-333,共9页
Although static program analysis methods are frequently employed to enhance software quality,their efficiency in commercial settings is limited by their high false positive rate.The EUGENE tool can effectively lower t... Although static program analysis methods are frequently employed to enhance software quality,their efficiency in commercial settings is limited by their high false positive rate.The EUGENE tool can effectively lower the false positive rate.However,in continuous integration(CI)environments,the code is always changing,and user feedback from one version of the software cannot be applied to a subsequent version.Additionally,people find it difficult to distinguish between true positives and false positives in the analytical output.In this study,we developed the EUGENE-CI technique to address the CI problem and the EUGENE-rank lightweight heuristic algorithm to rate the reports of the analysis output in accordance with the likelihood that they are true positives.On the three projects ethereum,go-cloud,and kubernetes,we assessed our methodologies.According to the trial findings,EUGENE-CI may drastically reduce false positives while EUGENE-rank can make it much easier for users to identify the real positives among a vast number of reports.We paired our techniques with GoInsight~1 and discovered a vulnerability.We also offered a patch to the community. 展开更多
关键词 continuous integration report ranking static program analysis
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Co-integration Analysis of the Relationship between Residents' Consumer Spending and GDP in Hubei Province
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作者 HE Xian-ping,FENG Jian-zhong, LIANG Jun School of Information and Mathematics,Yangtze University, Jingzhou 434023,China 《Asian Agricultural Research》 2011年第12期12-13,18,共3页
In accordance with the economic data from Statistical Communique on National Economy and Social Development in Hubei Province in the period 1980-2009, we use co-integration analysis method to research the impact of GD... In accordance with the economic data from Statistical Communique on National Economy and Social Development in Hubei Province in the period 1980-2009, we use co-integration analysis method to research the impact of GDP growth on residents' consumer spending. Result shows that although there are differences between GDP and residents' consumer spending in the short term, the equilibrium relationship exists between them, namely, the co-integration relationship, showing consistency in trends. 展开更多
关键词 GDP Residents’ CONSUMER SPENDING co-integration an
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Time series analysis-based seasonal autoregressive fractionally integrated moving average to estimate hepatitis B and C epidemics in China 被引量:1
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作者 Yong-Bin Wang Si-Yu Qing +3 位作者 Zi-Yue Liang Chang Ma Yi-Chun Bai Chun-Jie Xu 《World Journal of Gastroenterology》 SCIE CAS 2023年第42期5716-5727,共12页
BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their s... BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their spread is essential for developing effective strategies,heightening the requirement for early warning to deal with such a major public health threat.AIM To monitor HB and HC epidemics by the design of a paradigmatic seasonal autoregressive fractionally integrated moving average(SARFIMA)for projections into 2030,and to compare the effectiveness with the seasonal autoregressive integrated moving average(SARIMA).METHODS Monthly HB and HC incidence cases in China were obtained from January 2004 to June 2023.Descriptive analysis and the Hodrick-Prescott method were employed to identify trends and seasonality.Two periods(from January 2004 to June 2022 and from January 2004 to December 2015,respectively)were used as the training sets to develop both models,while the remaining periods served as the test sets to evaluate the forecasting accuracy.RESULTS There were incidents of 23400874 HB cases and 3590867 HC cases from January 2004 to June 2023.Overall,HB remained steady[average annual percentage change(AAPC)=0.44,95%confidence interval(95%CI):-0.94-1.84]while HC was increasing(AAPC=8.91,95%CI:6.98-10.88),and both had a peak in March and a trough in February.In the 12-step-ahead HB forecast,the mean absolute deviation(15211.94),root mean square error(18762.94),mean absolute percentage error(0.17),mean error rate(0.15),and root mean square percentage error(0.25)under the best SARFIMA(3,0,0)(0,0.449,2)12 were smaller than those under the best SARIMA(3,0,0)(0,1,2)12(16867.71,20775.12,0.19,0.17,and 0.27,respectively).Similar results were also observed for the 90-step-ahead HB,12-step-ahead HC,and 90-step-ahead HC forecasts.The predicted HB incidents totaled 9865400(95%CI:7508093-12222709)cases and HC totaled 1659485(95%CI:856681-2462290)cases during 2023-2030.CONCLUSION Under current interventions,China faces enormous challenges to eliminate HB and HC epidemics by 2030,and effective strategies must be reinforced.The integration of SARFIMA into public health for the management of HB and HC epidemics can potentially result in more informed and efficient interventions,surpassing the capabilities of SARIMA. 展开更多
关键词 HEPATITIS Seasonal autoregressive fractionally integrated moving average Seasonal autoregressive integrated moving average Prediction EPIDEMIC Time series analysis
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Research on the Comparison and Integration of Chinese and Western Music Cultures
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作者 LEI Shuwen 《Cultural and Religious Studies》 2024年第1期32-35,共4页
This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical e... This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical elements such as scales,modes,and compositional styles,illuminating shared threads and distinctive attributes that characterize Chinese and Western music.Against the backdrop of contemporary global dynamics,the research investigates the ongoing integration of these musical cultures.It explores the impact of globalization and technological advancements,revealing instances of cross-cultural collaboration and the emergence of hybrid musical forms.Augmenting theoretical discussions with concrete case studies,the paper offers illuminating examples of how Chinese and Western musical elements interweave,contributing to the evolving landscape of global music.This research not only advances scholarly understanding but also contributes practical insights for musicians,educators,and enthusiasts navigating the evolving dynamics of cross-cultural musical expression.By elucidating the intricate relationship between Chinese and Western music cultures,the paper underscores the richness borne out of their interaction and the cultural synthesis that defines contemporary musical landscapes. 展开更多
关键词 comparative music analysis cross-cultural integration hybrid forms globalization influence
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Feasibility Analysis of IMA Configuration Design Tool
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作者 FENG Guangding MENG Bo XIANG Yangkui 《International Journal of Plant Engineering and Management》 2024年第1期1-13,共13页
With the widespread application of integrated modular aviation(IMA)electronic systems,the requirements of IMA characteristic analysis and configuration generation have also improved significantly."Configuration a... With the widespread application of integrated modular aviation(IMA)electronic systems,the requirements of IMA characteristic analysis and configuration generation have also improved significantly."Configuration and design system based on AADL models(real-time,reliability,interactive complexity,and schedulability)analysis of the AADL model"mainly get through key characteristic analysis for optimization,combined with input of component parameter information and constraint information,assist designers in generating system configuration information,and form a comprehensive modular avionics system resource configuration strategy generation platform.Also,the tool can generate configuration plans for avionics system software and hardware physical architecture configuration.The analysis of the avionics system model mainly involves designers inputting the existing system model architecture for multi characteristic analysis,it can realize the multi-character analysis based on software intensive system architecture models for software dense systems.Inter-complexity and schedulability analysis,and according to characteristic constraint analysis、system model assessment parameters and system architecture constraint parameters to generate configuration scheme information that meets the requirements.The system can meet domestic and foreign software-intensive systems and meet its quality requirements. 展开更多
关键词 integrated modular aviation(IMA) multi-character analysis constraint analysis configuration generation
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Integrity and Failure Analysis of Cement Sheath Subjected to Coalbed Methane Fracturing
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作者 Lingyun Zhao Heng Yang +3 位作者 Yuanlong Wei Yuhuan Bu Shaorui Jing Peiming Zhou 《Fluid Dynamics & Materials Processing》 EI 2023年第2期329-344,共16页
Perforation and fracturing are typically associated with the development of coalbed methane wells.As the cement sheath is prone to failure during this process,in this work,the effects of the casing pressure,elastic mo... Perforation and fracturing are typically associated with the development of coalbed methane wells.As the cement sheath is prone to failure during this process,in this work,the effects of the casing pressure,elastic modulus of the cement,elastic modulus of the formation,and casing eccentricity on the resulting stresses are analyzed in the frame of a finite element method.Subsequently,sensitivity response curves of the cement sheath stress are plotted by normalizing all factors.The results show that the maximum circumferential stress and Mises stress of the cement sheath increase with the casing internal pressure,elastic modulus of the cement and casing eccentricity.As the elastic modulus of the formation increases,the maximum circumferential stress of the cement sheath decreases,and its maximum Mises stress increases slightly.The cement sheath undergoes tensile failure during coalbed methane fracturing.The stress sensitivity of the cement sheath to the influential parameters is in the following order:casing internal pressure>elastic modulus of cement sheath>casing eccentricity>elastic modulus of formation. 展开更多
关键词 Coalbed methane fracturing finite element method cement sheath integrity sensitivity analysis failure analysis
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Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means
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作者 Bo-Han Wu Ran-Hong Xie +3 位作者 Li-Zhi Xiao Jiang-Feng Guo Guo-Wen Jin Jian-Wei Fu 《Petroleum Science》 SCIE EI CSCD 2023年第5期2747-2758,共12页
In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tig... In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic parameters.The PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as input.The unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological profiles.The analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method. 展开更多
关键词 Tight sandstone integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means
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Integrated analysis of comorbidity, pregnant outcomes, and amniotic fluid cytogenetics of fetuses with persistent left superior vena cava
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作者 Xin Yang Xin-Hui Su +4 位作者 Zhen Zeng Yao Fan Yuan Wu Li-Li Guo Xiao-Yan Xu 《World Journal of Cardiology》 2023年第10期500-507,共8页
BACKGROUND Persistent left superior vena cava(PLSVC)is the most common venous system variant.The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.AIM To deve... BACKGROUND Persistent left superior vena cava(PLSVC)is the most common venous system variant.The clinical characteristics and amniotic fluid cytogenetics of fetuses with PLSVC remain to be further explored.AIM To develop reliable prenatal diagnostic recommendations through integrated analysis of the clinical characteristics of fetuses with PLSVC.METHODS Cases of PLSVC diagnosed using prenatal ultrasonography between September 2019 and November 2022 were retrospectively studied.The clinical characteristics of the pregnant women,ultrasonic imaging information,gestational age at diagnosis,pregnancy outcomes,and amniocentesis results were summarized and analyzed using categorical statistics and the chi-square test or Fisher’s exact test.RESULTS Of the 97 cases diagnosed by prenatal ultrasound,49(50.5%)had isolated PLSVC and 48(49.5%)had other structural abnormalities.The differences in pregnancy outcomes and amniocentesis conditions between the two groups were statistically significant(P<0.05).No significant differences were identified between the two groups in terms of advanced maternal age and gestational age(P>0.05).According to the results of the classification statistics,the most common intrac-ardiac abnormality was a ventricular septal defect and the most common extrac-ardiac abnormality was a single umbilical artery.In the subgroup analysis,the concurrent combination of intra-and extracardiac structural abnormalities was a risk factor for adverse pregnancy outcomes(odds ratio>1,P<0.05).Additional-ly,all abnormal cytogenetic findings on amniocentesis were observed in the comorbidity group.One case was diagnosed with 21-trisomy and six cases was diagnosed with chromosome segment duplication.CONCLUSION Examination for other structural abnormalities is strongly recommended when PLSVC is diagnosed.Poorer pregnancy outcomes and increased amniocentesis were observed in PLSVC cases with other structural abnor-malities.Amniotic fluid cytogenetics of fetuses is recommended for PLSVC with other structural abnormalities. 展开更多
关键词 Persistent left superior vena cava Prenatal diagnosis Amniotic fluid cytogenetics Pregnancy outcome integrated analysis COMORBIDITY
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AN ADAPTIVE ALGORITHM OF PRECISE INTEGRATION FOR TRANSIENT ANALYSIS 被引量:8
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作者 Zhang Hongwu Chen Biaosong gu Yuanxian 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第3期215-224,共10页
This paper presents an improved precise integration algorithm fortransient analysis of heat transfer and some other problems. Theoriginal precise integration method is improved by means of the inve-rse accuracy analys... This paper presents an improved precise integration algorithm fortransient analysis of heat transfer and some other problems. Theoriginal precise integration method is improved by means of the inve-rse accuracy analysis so that the parameter N, which has been takenas a constant and an independent pa- rameter without consideration ofthe problems in the original method, can be generated automaticallyby the algorithm itself. 展开更多
关键词 heat transfer analysis precise integration method inverse accuracyanalysis
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Isogeometric Boundary Element Analysis for 2D Transient Heat Conduction Problem with Radial Integration Method 被引量:3
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作者 Leilei Chen Kunpeng Li +3 位作者 Xuan Peng Haojie Lian Xiao Lin Zhuojia Fu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期125-146,共22页
This paper presents an isogeometric boundary element method(IGABEM)for transient heat conduction analysis.The Non-Uniform Rational B-spline(NURBS)basis functions,which are used to construct the geometry of the structu... This paper presents an isogeometric boundary element method(IGABEM)for transient heat conduction analysis.The Non-Uniform Rational B-spline(NURBS)basis functions,which are used to construct the geometry of the structures,are employed to discretize the physical unknowns in the boundary integral formulations of the governing equations.Bezier extraction technique is employed to accelerate the evaluation of NURBS basis functions.We adopt a radial integration method to address the additional domain integrals.The numerical examples demonstrate the advantage of IGABEM in dimension reduction and the seamless connection between CAD and numerical analysis. 展开更多
关键词 Isogeometric analysis NURBS boundary element method heat conduction radial integration method
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Reusing the Evaluations of Basis Functions in the Integration for Isogeometric Analysis 被引量:1
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作者 Zijun Wu Shuting Wang +1 位作者 Wenjun Shao Lianqing Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第2期459-485,共27页
We propose a new approach to reuse the basis function evaluations in the numerical integration of isogeometric analysis.The concept of reusability of the basis functions is introduced according to their symmetrical,tr... We propose a new approach to reuse the basis function evaluations in the numerical integration of isogeometric analysis.The concept of reusability of the basis functions is introduced according to their symmetrical,translational and proportional features on both the coarse and refined levels.Based on these features and the parametric domain regularity of each basis,we classify the bases on the original level and then reuse them on the refined level,which can reduce the time for basis calculations at integration nodes.By using the sum factorization method and the mean value theorem for the integrals,a new integration method with high integral efficiency is proposed.We validate the proposed method by some structural analysis problems in domains with different dimensionality.Comparing the numerical result accuracy and the time cost of the proposed integration method with the full Gauss integration quadrature,it turns out to be very promising. 展开更多
关键词 Isogeometric analysis NURBS REUSABILITY integration.
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Resolving Domain Integral Issues in Isogeometric Boundary Element Methods via Radial Integration:A Study of Thermoelastic Analysis 被引量:1
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作者 Shige Wang Zhongwang Wang +3 位作者 Leilei Chen Haojie Lian Xuan Peng Haibo Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第8期585-604,共20页
The paper applied the isogeometric boundary element method(IGABEM)to thermoelastic problems.The Non-Uniform Rational B-splines(NURBS)used to construct geometric models are employed to discretize the boundary integral ... The paper applied the isogeometric boundary element method(IGABEM)to thermoelastic problems.The Non-Uniform Rational B-splines(NURBS)used to construct geometric models are employed to discretize the boundary integral formulation of the governing equation.Due to the existence of thermal stress,the domain integral term appears in the boundary integral equation.We resolve this problem by incorporating radial integration method into IGABEM which converts the domain integral to the boundary integral.In this way,IGABEM can maintain its advantages in dimensionality reduction and more importantly,seamless integration of CAD and numerical analysis based on boundary representation.The algorithm is verified by numerical examples. 展开更多
关键词 Isogeometric analysis NURBS boundary element method THERMOELASTIC radial integration method
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