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The Impact of The Three-Dimensional Cultivation Model on the Development of the Suzhou Tea Industry:Estimating Value of Output Per Acre and Diversified Sales Models
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作者 Shan Hao 《Proceedings of Business and Economic Studies》 2024年第3期126-132,共7页
This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introdu... This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introduces the history and traditional cultivation practices of tea in Suzhou,as well as the current challenges and problems faced by the industry.An in-depth analysis was conducted on the overview and improvement plans of the three-dimensional cultivation mode,covering relevant technical methods.Based on this analysis,the impact of the three-dimensional cultivation on the value of output per acre was studied and predicted.Its potential and advantages were explored and compared with the effectiveness of traditional cultivation models.Additionally,the impact of the three-dimensional cultivation mode on sales was analyzed,examining its market adaptability and competitiveness,as well as its advantages in expanding sales channels and market coverage.The study also focused on the promoting effect of diversified sales models on the Suzhou tea industry,including direct consumption market development,tea processing product development and promotion,and the integration of tea culture and the tourism industry.To ensure sustainable development,the article evaluates the environmental impact,economic feasibility,social benefits,and farmer benefits of the three-dimensional cultivation model.Finally,the prospects for the development of the Suzhou tea industry were discussed,and the positioning and response strategies of the threedimensional cultivation model were proposed. 展开更多
关键词 Suzhou tea industry Stereoscopic cultivation mode Value of output per acre Sales model DIVERSIFICATION
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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Study on Current Situation,Existing Problems and Countermeasures of Soybean Cultivation
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作者 Huajun SUN 《Agricultural Biotechnology》 2025年第1期9-12,18,共5页
As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production an... As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production and processing.In view of this situation,this paper comprehensively expounded and decomposed the cultivation situation,existing problems,specific countermeasures and conclusions,so as to re-recognize them.This study provides reference materials for the sustainable and healthy development of the soybean industry. 展开更多
关键词 SOYBEAN cultivation situation PROBLEMS COUNTERMEASURE
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Interdisciplinary Education Paradigm:Exploration and Practice of the“Software Engineering+”Innovative Talent Cultivation Model
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作者 Mingzheng Hou Binyu Yan +2 位作者 Mei Hong Yi Zhang Mao Li 《计算机教育》 2025年第3期62-70,共9页
To address the severe challenges posed by the international situation and meet the needs of the national major development strategies,the traditional software engineering talent cultivation model lacks interdisciplina... To address the severe challenges posed by the international situation and meet the needs of the national major development strategies,the traditional software engineering talent cultivation model lacks interdisciplinary education focused on specific fields,making it difficult to cultivate engineering leaders with multidisciplinary backgrounds who are capable of solving complex real-world problems.To solve this problem,based on the decade-long interdisciplinary talent cultivation achievements of the College of Software Engineering at Sichuan University,this article proposes the“Software Engineering+”innovative talent cultivation paradigm.It provides an analysis through professional construction of interdisciplinary talents,the design of talent cultivation frameworks,the formulation of cultivation plans,the establishment of interdisciplinary curriculum systems,the reform of teaching modes,and the improvement of institutional systems.Scientific solutions are proposed,and five project models implemented and operated by the College of Software Engineering at Sichuan University are listed as practical examples,offering significant reference value. 展开更多
关键词 Software Engineering+ INTERDISCIPLINARY Talent cultivation Curriculum system
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Intensive Planting and High Yield Cultivation Techniques for Yuluxiang Pear in Hilly and Mountainous Regions
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作者 Liping XUE 《Plant Diseases and Pests》 2025年第1期31-33,共3页
In order to enhance the guidance for Yuluxiang pear cultivation in hilly and mountainous regions, this study provides a comprehensive introduction to various aspects, including the establishment of high-standard orcha... In order to enhance the guidance for Yuluxiang pear cultivation in hilly and mountainous regions, this study provides a comprehensive introduction to various aspects, including the establishment of high-standard orchards and the reinforcement of integrated management techniques, in order to offer a valuable reference for fruit farmers engaged in scientific planting practices. 展开更多
关键词 Yuluxiang pear High yield Intensive planting cultivation
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A Review of Three-Dimensional Research on Urban Recreation Space Based on CiteSpace
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作者 LIU Yongli 《Journal of Landscape Research》 2025年第1期30-34,共5页
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t... In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”. 展开更多
关键词 Compact city Urban recreation space three-dimensional CITESPACE
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Reconfigurable Three-Dimensional Thermal Dome
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作者 Yuhong Zhou Fubao Yang +5 位作者 Liujun Xu Pengfei Zhuang Dong Wang Xiaoping Ouyang Ying Li Jiping Huang 《Engineering》 2025年第3期236-244,共9页
Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of t... Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields. 展开更多
关键词 Thermal domes Reconfigurable metamaterials three-dimensional invisibility
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Research on the Evaluation Model of Software Talent Cultivation Based on Multivariant Data Fusion
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作者 Yin Chen Haoxuan Tang +4 位作者 Lei Zhang Tonghua Su Zhongjie Wang Ruihan Hu Shanli Xie 《计算机教育》 2025年第3期130-137,共8页
This paper proposes a multivariate data fusion based quality evaluation model for software talent cultivation.The model constructs a comprehensive ability and quality evaluation index system for college students from ... This paper proposes a multivariate data fusion based quality evaluation model for software talent cultivation.The model constructs a comprehensive ability and quality evaluation index system for college students from a perspective of engineering course,especially of software engineering.As for evaluation method,relying on the behavioral data of students during their school years,we aim to construct the evaluation model as objective as possible,effectively weakening the negative impact of personal subjective assumptions on the evaluation results. 展开更多
关键词 Quality evaluation model Software talent cultivation Behavioral data
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Exploration and Practice of Collaborative Talent Cultivation Model for Urban Horticulture under the Background of Smart Agriculture
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作者 Zhen Peng Yuerong Gao +1 位作者 Ziyan Liu Liusheng Duan 《Journal of Contemporary Educational Research》 2025年第1期198-204,共7页
This paper discusses the development characteristics of urban horticulture under the background of smart agriculture,as well as the application of artificial intelligence technology in it.It analyzes the importance of... This paper discusses the development characteristics of urban horticulture under the background of smart agriculture,as well as the application of artificial intelligence technology in it.It analyzes the importance of highly skilled talents in urban agriculture in the era of smart agriculture and their cultivation pathways and practices.It proposes measures such as building multi-level practical teaching platforms,implementing the“Enjoy Horticulture”series of high-quality activities,and establishing the“1234”applied talent training model to cultivate high-quality talents that meet the development needs of modern urban horticulture industry.Taking Beijing University of Agriculture and other universities as examples,the paper analyzes the practical cases and effects of the urban horticulture discipline’s industry-education-research collaborative talent training model,which has reference significance for further improving and perfecting the urban horticulture industry-education-research collaborative talent training plan. 展开更多
关键词 Agricultural modernization Smart agriculture Urban horticulture Industry-education-research collaboration Talent cultivation
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Developing Language Assessment Literacy of Pre-Service English Teachers:Frameworks and Cultivation Strategies
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作者 Jie Cao 《Journal of Contemporary Educational Research》 2025年第1期1-8,共8页
Assessment is a crucial aspect of the teaching process for teachers.Teachers’assessment literacy is closely related to students’learning outcomes.The language assessment literacy of foreign language teachers is a si... Assessment is a crucial aspect of the teaching process for teachers.Teachers’assessment literacy is closely related to students’learning outcomes.The language assessment literacy of foreign language teachers is a significant component of both teachers’professional development and students’learning,and it has become a research hotspot in the field of domestic language testing.Based on clarifying the theoretical framework of language assessment literacy,this paper proposes the main cultivation paths for pre-service English teachers’language assessment literacy,aiming to provide inspiration and references for the cultivation,reform,and development of teachers in basic foreign language education. 展开更多
关键词 Pre-service English teachers Language assessment literacy cultivation strategies
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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Reasonable dry cultivation methods can balance the yield and grain quality of rice
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作者 Jia Wu Luqi Zhang +4 位作者 Ziyi Wang Fan Ge Hao Zhang Jianchang Yang Yajie Zhang 《Journal of Integrative Agriculture》 2025年第3期1030-1043,共14页
Reducing water consumption in rice production in China without affecting grain yield and quality is a significant challenge.This study explored how various dry cultivation methods could improve rice quality while bala... Reducing water consumption in rice production in China without affecting grain yield and quality is a significant challenge.This study explored how various dry cultivation methods could improve rice quality while balancing yield to maintain sustainable rice production.A japonica upland rice cultivar and a japonica paddy rice cultivar were cultivated in the field with three cultivation methods:plastic film mulching dry cultivation(PFMC),bare dry cultivation(BC),and continuous flooding cultivation(CF)as control.There was no significant difference in upland rice yield between PFMC and BC,nor in paddy rice yield between PFMC and CF.Compared with CF,the two varieties'yields decreased significantly with BC.Dry cultivation,especially PFMC,could decrease the active filling period,chalky rice rate,chalkiness,amylose content,gel consistency,breakdown viscosity,the ratio of glutelin to prolamin,and leaf senescence while increasing water use efficiency,protein components content,setback viscosity,grain starch branching enzyme(Q-enzyme)activity,and average filling rate.Compared with paddy rice,upland rice had a lower yield,shorter active filling period,lower chalkiness grain rate and gel consistency,higher amylose content,breakdown viscosity,protein components content,and average filling rate.Grain Q-enzyme activity and grain-filling parameters were closely related to rice quality.Reasonable dry cultivation methods could balance yield and quality,especially by improving rice's nutritional and appearance quality. 展开更多
关键词 RICE dry cultivation grain quality YIELD protein components grain filling
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Research on the Path of Talent Cultivation Model for New Engineering Disciplines in the Era of Artificial Intelligence
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作者 Mengru Shen Baowen Li +1 位作者 Shasha Liu Hongchun Zhang 《Journal of Contemporary Educational Research》 2025年第3期34-39,共6页
The application of artificial intelligence(AI)in new engineering education can optimize course content and educational methods.AI provides personalized learning paths,adjusts teaching strategies,and improves teaching ... The application of artificial intelligence(AI)in new engineering education can optimize course content and educational methods.AI provides personalized learning paths,adjusts teaching strategies,and improves teaching management through real-time feedback.Despite its potential,challenges remain in balancing technology use with educational philosophies,ensuring fairness,and preventing over-reliance on technology.The integration of AI should focus on fostering critical thinking and problem-solving skills in students.By improving technical literacy and resource allocation,AI can enhance educational efficiency.However,to effectively implement AI,it requires deep integration with educational content,increased policy support,and continued collaboration between industries and academia. 展开更多
关键词 Artificial intelligence New engineering education Talent cultivation Educational reform Policy support
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Effects of macrophages on the osteogenic differentiation of adipose tissue-derived stem cells in two-dimensional and three-dimensional cocultures
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作者 He-Ao Zhang Bo-Yu Zhang Hong-Bo Tang 《World Journal of Stem Cells》 2025年第2期84-95,共12页
BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,tw... BACKGROUND Fracture is one of the most pervasive injuries in the musculoskeletal system,and there is a complex interaction between macrophages and adipose tissue-derived stem cells(ADSCs)in fracture healing.However,two-dimensional(2D)coculture of macrophages and ADSCs can not accurately mimic the in vivo cell microenvironment.AIM To establish both 2D and 3D osteogenic coculture models to investigate the interaction between macrophages and ADSCs.METHODS After obtaining ADSCs from surgery and inducing differentiation of the THP1 cell line,we established 2D and 3D osteogenic coculture models.To assess the level of osteogenic differentiation,we used alizarin red staining and measured the relative expression levels of osteogenic differentiation markers osteocalcin,Runt-related transcription factor 2,and alkaline phosphatase through polymerase chain reaction.Verification was conducted by analyzing the expression changes of N-cadherin and the activation of the Wnt/β-catenin signaling pathway using western blotting.RESULTS In this study,it was discovered that macrophages in 3D culture inhibited osteogenic differentiation of ADSCs,contrary to the effect in 2D culture.This observation confirmed the significance of intricate intercellular connections in the 3D culture environment.Additionally,the 3D culture group exhibited significantly higher N-cadherin expression and showed reducedβ-catenin and Wnt1 protein levels compared to the 2D culture group.CONCLUSION Macrophages promoted ADSC osteogenic differentiation in 2D culture conditions but inhibited it in 3D culture.The 3D culture environment might inhibit the Wnt/β-catenin signaling pathway by upregulating N-cadherin expression,ultimately hindering the osteogenic differentiation of ADSCs.By investigating the process of osteogenesis in ADSCs,this study provides novel ideas for exploring 3D osteogenesis in ADSCs,fracture repair,and other bone trauma repair. 展开更多
关键词 FRACTURE Adipose tissue-derived stem cells Osteogenic differentiation three-dimensional cell culture N-CADHERIN
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Three-dimensional finite-time optimal cooperative guidance with integrated information fusion observer
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作者 Yiao Zhan Linwei Wang Di Zhou 《Defence Technology(防务技术)》 2025年第4期12-28,共17页
Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an inte... Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an integrated approach that combines a Three-Dimensional Finite-Time Optimal Cooperative Guidance Law(FTOC)with an Information Fusion Anti-saturation Predefined-time Observer(IFAPO).The proposed FTOC guidance law employs a nonlinear,non-quadratic finite-time optimal control strategy designed for rapid convergence within the limited timeframes of near-space interceptions,avoiding the need for remaining flight time estimation or linear decoupling inherent in traditional methods.To complement the guidance strategy,the IFAPO leverages multi-source information fusion theory and incorporates anti-saturation mechanisms to enhance target maneuver estimation.This method ensures accurate and real-time prediction of target acceleration while maintaining predefined convergence performance,even under complex interception conditions.By integrating the FTOC guidance law and IFAPO,the approach optimizes cooperative missile positioning,improves interception success rates,and minimizes fuel consumption,addressing practical constraints in military applications.Simulation results and comparative analyses confirm the effectiveness of the integrated approach,demonstrating its capability to achieve cooperative interception of highly maneuvering targets with enhanced efficiency and reduced economic costs,aligning with realistic combat scenarios. 展开更多
关键词 Anti-saturation predefined-time observer Nonlinear finite-time optimal control three-dimensional guidance Information fusion
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On Three-dimensional Electron Diffraction Data Quality for Probing Molecular Motions
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作者 WANG Weiyuan HUANG Zhehao 《Chemical Research in Chinese Universities》 2025年第2期326-332,共7页
Molecular motions in metal-organic frameworks(MOFs)play important roles in vip diffusion processes,which is crucial for gas capture and separations.Three-dimensional electron diffraction(3DED)has emerged as an advan... Molecular motions in metal-organic frameworks(MOFs)play important roles in vip diffusion processes,which is crucial for gas capture and separations.Three-dimensional electron diffraction(3DED)has emerged as an advanced method to probe molecular motions,such as linker librations.For a study of molecular motions by 3DED,data quality is the key to the analysis and interpretation.Herein,we present a systematic work to investigate the effects of data completeness,resolution,and signal-to-noise ratio on the identification of molecular motion in MIL-140C.We determine the limits of completeness and resolution required for reliably analyzing molecular motions.In addition,data processing can affect the signal-to-noise ratio of data,and we demonstrate their influence on probing molecular motions.This work provides reference conditions on 3DED data quality to obtain reliable information on molecular motions. 展开更多
关键词 Metal-organic framework Molecular motion three-dimensional electron diffraction Data quality Thermal ellipsoid model
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A human-machine interaction method for rock discontinuities mapping by three-dimensional point clouds with noises
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作者 Qian Chen Yunfeng Ge +3 位作者 Changdong Li Huiming Tang Geng Liu Weixiang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1646-1663,共18页
Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results ca... Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features. 展开更多
关键词 Rock discontinuities three-dimensional(3D)point clouds Discontinuity identification Orientation measurement Human-machine interaction
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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection Digital joint mapping Rock discontinuities characterization three-dimensional(3D)trace network
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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions
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作者 Chentong GAO Huiyu SUN +1 位作者 Jianping GU W.M.HUANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期123-138,共16页
Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade compone... Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade components.In this paper,a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established.Based on Kirchhoff's plate assumptions,the displacement variables of the plate are expressed.By incorporating the braiding directions into the constitutive equation of the braided composites,the dynamic model of the plate considering braiding directions is obtained.The effects of the speeds,braiding directions,and braided angles on the responses of the plate with fixed-axis rotation and translational motion,respectively,are investigated.This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions.It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications. 展开更多
关键词 three-dimensional(3D)braided composite braiding direction composite thin plate large overall motion dynamic model
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A MIXED FINITE ELEMENT AND UPWIND MIXED FINITE ELEMENT MULTI-STEP METHOD FOR THE THREE-DIMENSIONAL POSITIVE SEMI-DEFINITE DARCY-FORCHHEIMER MISCIBLE DISPLACEMENT PROBLEM
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作者 Yirang YUAN Changfeng LI +1 位作者 Huailing SONG Tongjun SUN 《Acta Mathematica Scientia》 2025年第2期715-736,共22页
In this paper,a composite numerical scheme is proposed to solve the threedimensional Darcy-Forchheimer miscible displacement problem with positive semi-definite assumptions.A mixed finite element is used for the fow e... In this paper,a composite numerical scheme is proposed to solve the threedimensional Darcy-Forchheimer miscible displacement problem with positive semi-definite assumptions.A mixed finite element is used for the fow equation.The velocity and pressure are computed simultaneously.The accuracy of velocity is improved one order.The concentration equation is solved by using mixed finite element,multi-step difference and upwind approximation.A multi-step method is used to approximate time derivative for improving the accuracy.The upwind approximation and an expanded mixed finite element are adopted to solve the convection and diffusion,respectively.The composite method could compute the diffusion flux and its gradient.It possibly becomes an eficient tool for solving convection-dominated diffusion problems.Firstly,the conservation of mass holds.Secondly,the multi-step method has high accuracy.Thirdly,the upwind approximation could avoid numerical dispersion.Using numerical analysis of a priori estimates and special techniques of differential equations,we give an error estimates for a positive definite problem.Numerical experiments illustrate its computational efficiency and feasibility of application. 展开更多
关键词 Darcy-Forchheimer fow three-dimensional positive semi-definite problem upwind mixed finite element multi-step method conservation of mass convergence analysis
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