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Development of a toroidal soft x-ray imaging system and application for investigating three-dimensional plasma on J-TEXT
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作者 赵传旭 李建超 +9 位作者 张晓卿 王能超 丁永华 杨州军 江中和 严伟 李杨波 毛飞越 任正康 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期94-99,共6页
A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and locat... A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and located on the vacuum chamber wall at toroidal positionsφof 126.4°and 272.6°,respectively,while one set was established previously atφ=65.50.Each set of SXR arrays consists of three arrays viewing the plasma poloidally,and hence can be used separately to obtain SXR images via the tomographic method.The sawtooth precursor oscillations are measured by T-SXRI,and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions,hence providing measurement of the 3D structure of precursor oscillations.The observed 3D structure is consistent with the helical structure of the m/n=1/1 mode.The experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma. 展开更多
关键词 SXR imaging J-TEXT tokamak three-dimensional measurement MHD
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Teaching Path and Countermeasures of New Media Advertising Based on “Three-dimensional” Practical Teaching System
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作者 WANG Hui CHEN Chunxiao LI Xiu 《Journal of Landscape Research》 2022年第6期95-98,共4页
By analyzing the dilemma encountered in practical teaching of new media advertising course in the digital economy era, this paper explores the teaching path of new media advertising course based on “three-dimensional... By analyzing the dilemma encountered in practical teaching of new media advertising course in the digital economy era, this paper explores the teaching path of new media advertising course based on “three-dimensional” practical teaching system, and believes that it is necessary to accurately determine talent training objectives, and construct the three dimensions of practical teaching, practical ability, and new media entrepreneurship and employment. Finally, the teaching countermeasures of practical teaching system based on three dimensions are put forward. 展开更多
关键词 “three-dimensional”practical teaching system New media advertising PATH COUNTERMEASURE
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Application of three-dimensional speckle tracking technique in measuring left ventricular myocardial function in patients with diabetes
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作者 Zheng Li Ying Qian +1 位作者 Chun-Yun Fan Yong Huang 《World Journal of Diabetes》 SCIE 2024年第4期783-792,共10页
BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use... BACKGROUND Diabetic cardiomyopathy is considered as a chronic complication of diabetes mellitus(DM).Therefore,early detection of left ventricular systolic function(LVSF)damage in DM is essential.AIM To explore the use of the three-dimensional speckle tracking technique(3D-STI)for measuring LVSF in DM patients via meta-analysis.METHODS The electronic databases were retrieved from the initial accessible time to 29 April 2023.The current study involved 9 studies,including 970 subjects.We carried out this meta-analysis to estimate myocardial function in DM compared with controls according to myocardial strain attained by 3D-STI.RESULTS Night articles including 970 subjects were included.No significant difference was detected in the left ventricular ejection fraction between the control and the diabetic group(P>0.05),while differences in global longitudinal strain,global circumferential strain,global radial strain,and global area strain were markedly different between the controls and DM patients(all P<0.05).CONCLUSION The 3D-STI could be applied to accurately measure early LVSF damage in patients with DM. 展开更多
关键词 Diabetes mellitus Left ventricular systolic dysfunction three-dimensional speckle tracking echocardiography Meta analysis
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Practical effect of different teaching modes in teaching gastrointestinal surgery nursing
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作者 Xiao-Juan Rong Zhen Ning 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期166-172,共7页
BACKGROUND With the continuous development and progress of medical technology,the position of surgical nursing in the field of clinical medicine is becoming in-creasingly prominent.As an important branch of the surgic... BACKGROUND With the continuous development and progress of medical technology,the position of surgical nursing in the field of clinical medicine is becoming in-creasingly prominent.As an important branch of the surgical field,the nursing requirements and difficulty of gastrointestinal surgery are also increasing.In order to improve the teaching quality of nursing care in gastrointestinal surgery,many educators and researchers are actively exploring new teaching methods.Among them,the teaching method case-based learning(CBL),scene-simulated learning(SSL),task-based learning(TBL),combining self-evaluation and training mode is considered as an effective method.This method aims to help students to better master knowledge and skills and improve their comprehensive quality by cultivating their self-evaluation ability.AIM To explore the practical effect of CBL-SSL-TBL combined with training mode and student self-assessment in nursing teaching of gastrointestinal surgery.METHODS Seventy-one nursing interns in our hospital from December 2020 to December 2021 were selected.According to different teaching modes,they were divided into observation group CBL-SSL-TBL combined with training mode combined with student self-assessment and control group(conventional teaching mode),of which 36 were in observation group and 35 were in control group.The results of operational skills,theoretical knowledge,nursing students'satisfaction,learning effectiveness questionnaire and teaching effect were compared between the two groups.RESULTS Compared between the two groups,the operational skills and theoretical knowledge scores of the observation group were higher than those of the control group,and the difference was statistically significant(P<0.05).Compared between the two groups,the total satisfaction ratio of the observation group was higher than that of the control group,the difference was statistically significant(P<0.05).Compared between the two groups,the observation group was lower than the control group in the questionnaire results of learning efficacy,and the difference was statistically significant(P<0.05).Compared between the two groups,the proportion of thinking ability,subjective initiative and understanding of theoretical knowledge in the observation group was higher than that in the control group,the difference was statistically significant(P<0.05).CONCLUSION The use of CBL-SSL-TBL combined with training mode and student self-assessment in gastrointestinal surgery nursing teaching can improve the operational skills of nursing interns,theoretical knowledge and satisfaction scores of nursing students,improve the results of learning efficiency questionnaire and teaching effect,which can be popularized in clinical teaching. 展开更多
关键词 Gastrointestinal surgery Nursing teaching Teaching model practical effect Learning ability
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Practical Research on Promoting the Reform of“One Field for One Household”in Guoyang County
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作者 HOU Limin 《Journal of Landscape Research》 2024年第1期83-85,90,共4页
In recent years,the problem of farmland fragmentation has become a major obstacle to the development of modern agriculture,and the reform of“one field for one household”can effectively sort out cultivated land resou... In recent years,the problem of farmland fragmentation has become a major obstacle to the development of modern agriculture,and the reform of“one field for one household”can effectively sort out cultivated land resources,increase contracted land area,improve land utilization rate,and effectively solve the problems of contracted land dispersion and farmland fragmentation in rural areas.This paper systematically anatomized the practice and effects of“one household,one field”reform in Guoyang County,analyzed the problems existing in the implementation process,and put forward corresponding suggestions and countermeasures,in order to provide experience and reference for the reform of one field in other regions. 展开更多
关键词 One field for each household Reform practice Guoyang County
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The combined application of stem cells and three-dimensional bioprinting scaffolds for the repair of spinal cord injury
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作者 Dingyue Ju Chuanming Dong 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1751-1758,共8页
Spinal cord injury is considered one of the most difficult injuries to repair and has one of the worst prognoses for injuries to the nervous system.Following surgery,the poor regenerative capacity of nerve cells and t... Spinal cord injury is considered one of the most difficult injuries to repair and has one of the worst prognoses for injuries to the nervous system.Following surgery,the poor regenerative capacity of nerve cells and the generation of new scars can make it very difficult for the impaired nervous system to restore its neural functionality.Traditional treatments can only alleviate secondary injuries but cannot fundamentally repair the spinal cord.Consequently,there is a critical need to develop new treatments to promote functional repair after spinal cord injury.Over recent years,there have been seve ral developments in the use of stem cell therapy for the treatment of spinal cord injury.Alongside significant developments in the field of tissue engineering,three-dimensional bioprinting technology has become a hot research topic due to its ability to accurately print complex structures.This led to the loading of three-dimensional bioprinting scaffolds which provided precise cell localization.These three-dimensional bioprinting scaffolds co uld repair damaged neural circuits and had the potential to repair the damaged spinal cord.In this review,we discuss the mechanisms underlying simple stem cell therapy,the application of different types of stem cells for the treatment of spinal cord injury,and the different manufa cturing methods for three-dimensional bioprinting scaffolds.In particular,we focus on the development of three-dimensional bioprinting scaffolds for the treatment of spinal cord injury. 展开更多
关键词 BIOMATERIALS embryonic stem cells induced pluripotent stem cells mesenchymal stem cells nerve regeneration spinal cord injury stem cell therapy stem cells three-dimensional bioprinting
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The Youth’s View of Marriage in Chinese Mainstream Media Discourse-A Corpus-assisted Three-dimensional Discourse Analysis
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作者 DING Shu-li LIN Ying 《Journal of Literature and Art Studies》 2024年第4期284-289,共6页
The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse an... The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse analysis model,this paper builds a“Chinese media News Report Corpus on the topic of‘marriage’”whose news are collected from China Daily.It is found that the discourses are neutral and objective with regard to the advantages and disadvantages of marriage,but in general,it is still a traditional view of marriage that is inevitable and closely related to fertility.Although this is controlled by the policies and the social reasons including declining fertility rate,it deviates from the current view of the youth towards marriage,resulting in many serious consequences such as young people’s rejection.In addition,this research found that male and female have great differences in their views on marriage,and men’s resistance to marriage is far greater than that of women,which is departure from the public’s cognition.The reasons behind this need to be explored in order to solve the marriage and love problems of young people in today’s era and realize the healthy development of young marriage. 展开更多
关键词 CORPORA three-dimensional discourse analysis the youth’view of marriage
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Theory,technology and practice of shale gas three-dimensional development:A case study of Fuling shale gas field in Sichuan Basin,SW China 被引量:1
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作者 SUN Huanquan CAI Xunyu +5 位作者 HU Degao LU Zhiyong ZHAO Peirong ZHENG Aiwei LI Jiqing WANG Haitao 《Petroleum Exploration and Development》 SCIE 2023年第3期651-664,共14页
In the Jiaoshiba block of the Fuling shale gas field,the employed reserves and recovery factor by primary well pattern are low,no obvious barrier is found in the development layer series,and layered development is dif... In the Jiaoshiba block of the Fuling shale gas field,the employed reserves and recovery factor by primary well pattern are low,no obvious barrier is found in the development layer series,and layered development is difficult.Based on the understanding of the main factors controlling shale gas enrichment and high production,the theory and technology of shale gas three-dimensional development,such as fine description and modeling of shale gas reservoir,optimization of three-dimensional development strategy,highly efficient drilling with dense well pattern,precision fracturing and real-time control,are discussed.Three-dimensional development refers to the application of optimal and fast drilling and volume fracturing technologies,depending upon the sedimentary characteristics,reservoir characteristics and sweet spot distribution of shale gas,to form"artificial gas reservoir"in a multidimensional space,so as to maximize the employed reserves,recovery factor and yield rate of shale gas development.In the research on shale gas three-dimensional development,the geological+engineering sweet spot description is fundamental,the collaborative optimization of natural fractures and artificial fractures is critical,and the improvement of speed and efficiency in drilling and fracturing engineering is the guarantee.Through the implementation of three-dimensional development,the overall recovery factor in the Jiaoshiba block has increased from 12.6%to 23.3%,providing an important support for the continuous and stable production of the Fuling shale gas field. 展开更多
关键词 shale gas three-dimensional development Fuling shale gas field Sichuan Basin fine reservoir description precision fracturing recoveryfactor
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Reform of Practical Teaching of “Linux Operating System Fundamentals” Under the Background of Emerging Engineering Education
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作者 Zhenhua Wang Chunli Chen Yuzhu Wang 《Journal of Contemporary Educational Research》 2024年第3期19-26,共8页
With the advancement of the construction of emerging engineering education,the reform of practical teaching has become an important task of higher engineering education.This article takes the course“Linux Operating S... With the advancement of the construction of emerging engineering education,the reform of practical teaching has become an important task of higher engineering education.This article takes the course“Linux Operating System Fundamentals”as an example to explore practical teaching reform in the context of emerging engineering education.By analyzing the current situation and problems in course practical teaching,we proposed practical teaching reforms such as online experiments,practical content updates,project-based engineering practices,and diversified evaluation models,and designed corresponding implementation plans.Practice has proved that this reform can improve students’learning interest and engineering practical skills,and cultivate outstanding engineers with innovative spirit and practical skills. 展开更多
关键词 Emerging engineering education practical teaching reform Project practice Virtual experiments
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Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus
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作者 Saleh Fahad Alqifari Omar Alkomi +13 位作者 Abdullah Esmail Khadijeh Alkhawami Shahd Yousri Mohamad Ayham Muqresh Nawwarah Alharbi Abdullah A Khojah Ahmed Aljabri Abdulrahman Allahham Kousalya Prabahar Hanan Alshareef Mohammed Aldhaeefi Tariq Alrasheed Ali Alrabiah Laila A AlBishi 《World Journal of Diabetes》 SCIE 2024年第3期331-347,共17页
Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus common second-line choice after metformin for treating T2... Practical guide:Glucagon-like peptide-1 and dual glucosedependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonists in diabetes mellitus common second-line choice after metformin for treating T2DM.Various considerations can make selecting and switching between different GLP-1 RAs challenging.Our study aims to provide a comprehensive guide for the usage of GLP-1 RAs and dual GIP and GLP-1 RAs for the management of T2DM. 展开更多
关键词 Glucagon-like peptide-1 receptor agonist Diabetes mellitus Metabolic syndrome Dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist Clinical practice ENDOCRINOLOGY
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Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique
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作者 JING Xiangyu HUANG Weiyi KAN Jiangming 《Journal of Arid Land》 SCIE CSCD 2024年第4期500-517,共18页
Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materia... Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi surfaces.It is challenging to describe these processes according to a uniform morphology.Therefore,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of gravel.Collecting morphology information for Gobi gravels is essential for studying its genesis and sand saltation.To enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in March 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain size.Leveraging multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear quality.Additionally,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point clouds.Advanced point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual gravels.These systematic processes allow precise and detailed characterization of individual gravels.For gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodology for measuring 3D parameters of individual gravels.The proposed workflow yields accurate calculations of relevant parameters for Gobi gravels,providing essential data support for subsequent studies on Gobi environments. 展开更多
关键词 Gobi gravels three-dimensional(3D)parameters point cloud 3D reconstruction Random Sample Consensus(RANSAC)algorithm Density-Based Spatial Clustering of Applications with Noise(DBSCAN)
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Research on the Reform of Practical Teaching of Internet of Things Engineering in the Context of New Engineering
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作者 Kongduo Xing Ling Pan 《Journal of Electronic Research and Application》 2024年第2期74-78,共5页
The emergence of new engineering disciplines has resulted in the growing trend of cross-discipline,and the enhancement of students’technical application ability has become the main teaching objective of engineering d... The emergence of new engineering disciplines has resulted in the growing trend of cross-discipline,and the enhancement of students’technical application ability has become the main teaching objective of engineering disciplines.For this reason,the Internet of Things(IoT)engineering program should be actively reformed,providing students with sufficient opportunities to improve their practical skills.This paper identifies the challenges within practical teaching of IoT engineering,delves into effective strategies for practical IoT teaching within the context of emerging engineering disciplines,and presents practical teaching experiences from the School of Information Engineering at Hainan University of Science and Technology as a case study.The aim is to offer guidance and insights to educators in this field. 展开更多
关键词 New engineering background Internet of Things engineering major practice teaching
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Reform of the Comprehensive Practical Course System for Mechanical and Electronic Engineering Majors Under the Background of New Engineering
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作者 Yali Yu Keyi Wang Yong Yang 《Journal of Contemporary Educational Research》 2024年第2期85-90,共6页
Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technologi... Under the background of new engineering,the reform of the comprehensive practical course system for mechanical and electronic engineering majors actively responds to the challenges posed by the new round of technological revolution and industrial transformation to higher education,cultivating top-notch innovative intellectuals with comprehensive engineering qualities,meeting the requirements of being able to solve complex engineering problems rather than just cognitive capabilities,forming two core courses through reconstructing and reshaping the core courses of the major.The core courses include Drive,Measurement,and Control I and Drive,Measurement,and Control II,which highlight the comprehensive framework of mechanical and electronic engineering professional knowledge,continuing the comprehensive practical course system based on the unity of knowledge and practice,following the trend of new engineering,highlighting the practicality of professional innovation,assisting engineering education reform,and promoting high-quality development of new engineering professionals cultivation. 展开更多
关键词 Comprehensive engineering quality Mechanical and Electronic Engineering practical course system New engineering
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A Brief Discussion on the Construction of Practical Teaching System for the Traditional Chinese Medicine Resources and Development Major
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作者 Jiangwei Tian 《Journal of Contemporary Educational Research》 2024年第2期57-61,共5页
China’s traditional medicine,science,and technology industry has great development potential.However,there is a problem of insufficient practitioners in the current industrial development.At the same time,the capabil... China’s traditional medicine,science,and technology industry has great development potential.However,there is a problem of insufficient practitioners in the current industrial development.At the same time,the capabilities of existing practitioners do not match the demand standards.Therefore,it is necessary to actively promote the education of resources and development in Central Asia.As an institution for cultivating talents,colleges and universities must establish a practical teaching system for cultivating talents.Based on the requirements put forward by China in education,this article studies the development status of the traditional Chinese medicine resources and development major,determines the talent training goals,starts from the practical teaching aspect,and locates the industry’s requirements for the capabilities of personnel in the field of traditional Chinese medicine.It also puts forward the overall idea of the construction of the practical teaching system,summarizes the reform content of the practical teaching system,and lastly provides the specific path of the reform. 展开更多
关键词 Traditional Chinese medicine resources and development practical teaching Teaching resources
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Research on Practical Teaching of Ideological and Political Courses in Colleges and Universities and Collaborative Education in the Second Classroom
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作者 Luhua Xiao Pingping Liu Zimeng Li 《Journal of Contemporary Educational Research》 2024年第1期214-220,共7页
In today’s society,the need for talent training is of utmost importance due to rapid development.To achieve high-quality talent training,we need to focus on building a collaborative education mechanism.Practical teac... In today’s society,the need for talent training is of utmost importance due to rapid development.To achieve high-quality talent training,we need to focus on building a collaborative education mechanism.Practical teaching and the second classroom,which serve as important carriers of educational talents,must align their educational goals and complement each other.This article explores the collaborative education mechanism of the second classroom and practical teaching for the ideological and political courses in colleges and universities.It proposes reasonable construction measures to provide some guidelines for teaching work. 展开更多
关键词 Colleges and universities Ideological and political courses practical teaching Second classroom Collaborative education
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Three-dimensional Practical Teaching of Tourism Management Specialty in Local Colleges Based on Idea of Cooperative Innovation
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作者 Zhang Hongyan 《International Journal of Technology Management》 2017年第2期73-75,共3页
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GPU-accelerated three-dimensional reconstruction method of the Compton camera and its application in radionuclide imaging 被引量:1
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作者 Ren-Yao Wu Chang-Ran Geng +6 位作者 Feng Tian Zhi-Yang Yao Chun-Hui Gong Hao-Nan Han Jian-Feng Xu Yong-Shun Xiao Xiao-Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期54-68,共15页
A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method wit... A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method with scattering angle correction(CSS-BP-SC) can quickly perform the back-projection process of the Compton cone and can be used to precompute the list-mode maximum likelihood expectation maximization(LM-MLEM). A dedicated parallel architecture was designed for the graphics processing unit acceleration of the back-projection and iteration stage of the CSS-BP-SC-based LM-MLEM. The imaging results of the two-point source Monte Carlo(MC) simulation demonstrate that by analyzing the full width at half maximum along the three coordinate axes, the CSS-BP-SC-based LM-MLEM can obtain imaging results comparable to those of the traditional reconstruction algorithm, that is, the simple back-projection-based LM-MLEM. The imaging results of the mouse phantom MC simulation and experiment demonstrate that the reconstruction results obtained by the proposed method sufficiently coincide with the set radioactivity distribution, and the speed increased by more than 664 times compared to the traditional reconstruction algorithm in the mouse phantom experiment. The proposed method will further advance the imaging applications of Compton cameras. 展开更多
关键词 Compton camera three-dimensional reconstruction Radionuclide imaging GPU
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Incorporation ofκ-carrageenan improves the practical features of agar/konjac glucomannan/κ-carrageenan ternary system 被引量:1
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作者 Dongling Qiao Hao Li +3 位作者 Fatang Jiang Siming Zhao Sheng Chen Binjia Zhang 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期512-519,共8页
Three materials(agar,konjac glucomannan(KGM)andκ-carrageenan)were used to prepare ternary systems,i.e.,sol-gels and their dried composites conditioned at varied relative humidity(RH)(33%,54%and 75%).Combined methods,... Three materials(agar,konjac glucomannan(KGM)andκ-carrageenan)were used to prepare ternary systems,i.e.,sol-gels and their dried composites conditioned at varied relative humidity(RH)(33%,54%and 75%).Combined methods,e.g.,scanning electron microscopy,small-angle X-ray scattering,infrared spectroscopy(IR)and X-ray diffraction(XRD),were used to disclose howκ-carrageenan addition tailors the features of agar/KGM/κ-carrageenan ternary system.As affirmed by IR and XRD,the ternary systems withκ-carrageenan below 25%(agar/KGM/carrageenan,50:25:25,m/m)displayed proper component interactions,which increased the sol-gel transition temperature and the hardness of obtained gels.For instance,the ternary composites could show hardness about 3 to 4 times higher than that for binary counterpart.These gels were dehydrated to acquire ternary composites.Compared to agar/KGM composite,the ternary composites showed fewer crystallites and nanoscale orders,and newly-formed nanoscale structures from chain assembly.Such multi-scale structures,for composites withκ-carrageenan below 25%,showed weaker changes with RH,as revealed by especially morphologic and crystalline features.Consequently,the ternary composites with lessκ-carrageenan(below 25%)exhibited stabilized elongation at break and hydrophilicity at different RHs.This hints to us that agar/KGM/κ-carrageenan composite systems can display series applications with improved features,e.g.,increased sol-gel transition point. 展开更多
关键词 Agar/konjac glucomannan/κ-carrageenan ternary system Component interaction Multi-scale structure practical features
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Shear behavior of intact granite under thermo-mechanical coupling and three-dimensional morphology of shear-formed fractures 被引量:1
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作者 Bing Chen Baotang Shen Haiyang Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期523-537,共15页
The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine construction.Under the effect of a continuous engineering disturbance,shear... The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine construction.Under the effect of a continuous engineering disturbance,shear-formed fractures are prone to secondary instability,posing a severe threat to deep engineering.Although numerous studies regarding three-dimensional(3D)morphologies of fracture surfaces have been conducted,the understanding of shear-formed fractures under TM coupling conditions is limited.In this study,direct shear tests of intact granite under various TM coupling conditions were conducted,followed by 3D laser scanning tests of shear-formed fractures.Test results demonstrated that the peak shear strength of intact granite is positively correlated with the normal stress,whereas it is negatively correlated with the temperature.The internal friction angle and cohesion of intact granite significantly decrease with an increase in the temperature.The anisotropy,roughness value,and height of the asperities on the fracture surfaces are reduced as the normal stress increases,whereas their variation trends are the opposite as the temperature increases.The macroscopic failure mode of intact granite under TM coupling conditions is dominated by mixed tensileeshear and shear failures.As the normal stress increases,intragranular fractures are developed ranging from a local to a global distribution,and the macroscopic failure mode of intact granite changes from mixed tensileeshear to shear failure.Finally,3D morphological characteristics of the asperities on the shear-formed fracture surfaces were analyzed,and a quadrangular pyramid conceptual model representing these asperities was proposed and sufficiently verified. 展开更多
关键词 Thermo-mechanical(TM)coupling Peak shear strength three-dimensional(3D)morphological characterization Failure mode Quadrangular pyramid model
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Effect of Weft Binding Structure on Compression Properties of Three-Dimensional Woven Spacer Fabrics and Composites 被引量:1
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作者 刘生杰 江飞 +3 位作者 曾金金 邵慧奇 蒋金华 陈南梁 《Journal of Donghua University(English Edition)》 CAS 2023年第5期490-499,共10页
With the wide use of three-dimensional woven spacer composites(3DWSCs),the market expects greater mechanical properties from this material.By changing the weft fastening method of the traditional I-shape pile yarns,we... With the wide use of three-dimensional woven spacer composites(3DWSCs),the market expects greater mechanical properties from this material.By changing the weft fastening method of the traditional I-shape pile yarns,we designed three-dimensional woven spacer fabrics(3DWSFs)and 3DWSCs with the weft V-shape to improve the compression performance of traditional 3DWSFs.The effects of weft binding structures,V-pile densities,and V-shaped angle were investigated in this paper.It is found that the compression resistance of 3DWSFs with the weft V-shape is improved compared to that with the weft I-shape,the fabric height recovery rate is as high as 95.7%,and the average elastic recovery rate is 59.39%.When the interlayer pile yarn density is the same,the weft V-shaped and weft I-shaped 3DWSCs have similar flatwise pressure and edgewise pressure performance.The compression properties of the composite improve as the density of the V-pile yarns increases.The flatwise compression load decreases as the V-shaped angle decreases.When the V-shaped angle is 28°and 42°,the latitudinal V-shaped 3DWSCs perform exceptionally well in terms of anti-compression cushioning.The V-shaped weft binding method offers a novel approach to structural design of 3DWSCs. 展开更多
关键词 weft V-shaped binding three-dimensional woven spacer fabric(3DWSF) compression property pile yarn density V-shaped angle
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