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Asymmetric construction of non-activated C-SCF_(3) stereocenter via copper-catalyzed hydroallylation of SCF_(3)-alkenes
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作者 Wei-Cheng Zhao Yan He +4 位作者 Chen-Hui Jiang Peng Liu Qian Gao Duo-Duo Hu Xi-Sheng Wang 《Chinese Chemical Letters》 2026年第2期424-429,共6页
Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical ... Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products. 展开更多
关键词 Asymmetric construction Non-activated Hydroallylation Trifluoromethylthio group COPPER-CATALYZED
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The Construction of Ouyang Xiu's Posthumous Image in the Song Dynasty
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作者 Yang Xiangkui Wang Minhan 《Contemporary Social Sciences》 2026年第1期18-34,共17页
The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song D... The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song Dynasty,writings by Ouyang Xiu's family and epitaphs by his colleagues crafted a balanced narrative emphasizing both his official duties and literary merits,thus constructing a dual image of him as a principled remonstrator and a literary master.In the Southern Song Dynasty,official historiography gradually eroded his complex persona as a political reformer by selectively trimming political disputes and emphasizing his literary lineage,ultimately establishing him as a cultural exemplar beyond factional strife.Throughout this evolution of historical writing,Ouyang Xiu's sharpness as a remonstrator was gradually obscured in historical texts,while his image as a literary master,revered by all,became firmly established.The reshaping of Ouyang Xiu's image in historical writings across the Northern and Southern Song dynasties not only reflects the logic of selecting scholar-official role models under the influence of official ideology but also reveals the inherent pattern whereby individual distinctiveness fades into symbolic construction in historical writing. 展开更多
关键词 Ouyang Xiu image construction biographical writing canonization
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Exploration and Practical Research on the Construction Model of the Emergency Care System Based on the Concept of“Linkage”
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作者 Yan Li 《Journal of Clinical and Nursing Research》 2026年第1期138-144,共7页
Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching t... Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching the construction of an emergency care system based on the concept of“linkage”,delving into its theoretical foundations,exploring innovative construction models,and analyzing practical cases.The study indicates that an emergency care system under the“linkage”concept can effectively integrate resources and enhance efficiency,providing new insights for improving the construction of the emergency care system.It aims to promote the development of the emergency care system towards a more scientific,efficient,and collaborative direction. 展开更多
关键词 Linkage concept Emergency care system construction model Practical cases
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Effects of the Xu-Argument-Based Continuation on L2 Syntactic Complexity:The Case of Verb-Argument Constructions
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作者 Xiaopeng Zhang Jianhua Chen 《Chinese Journal of Applied Linguistics》 2026年第1期38-56,159,160,共21页
This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants... This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs. 展开更多
关键词 the xu-argument-based continuation task syntactic complexity verb-argument constructions Chinese high-school students
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Identification of Key Parameters for Temporary Guy Ropes in Sloping Central Tower Column and Brace Construction
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作者 Renfei Chang Liqiang Jin +2 位作者 Haihui Xie Kai Zhang Musheng Ye 《Structural Durability & Health Monitoring》 2026年第1期161-177,共17页
To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite ... To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects. 展开更多
关键词 Anisotropic single tower cable-stayed bridge influence degree identification temporary cables temporary diagonal braces construction control
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Standards lead the high-quality development of intelligent construction in China
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作者 Cheng Zhijun 《China Standardization》 2026年第1期49-49,共1页
To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction fou... To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial). 展开更多
关键词 STANDARDS technical guidelines high quality development Ministry Housing Urban Rural Development intelligent constructionstandards replicable experience intelligent construction
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Constructive alignment在财务管理教学中的应用探析
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作者 甘丽凝 《全国商情》 2010年第12期90-91,共2页
本文针对财务管理课程特点,提出了constructive alignment教学方法,并针对财务管理的投资决策部分,详细阐述了constructive alignment在财务管理教学中的具体应用。
关键词 constructive ALIGNMENT 财务管理 教学方法
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Review of preventive and constructive measures for coal mine explosions:An Indian perspective 被引量:9
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作者 Santosh Kumar Ray Asfar Mobin Khan +3 位作者 Niroj Kumar Mohalik Debashish Mishra Somu Mandal Jai Krishna Pandey 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期471-485,共15页
Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different... Firedamp and coal dust explosion constitute a lion’s share in mine accidents in a global mining scenario.This paper reports a list of mine explosion disasters since last two decades,a critical review of the different prevention and constructive measures,and its recent development to avoid firedamp and coal dust explosion.Preventive legislation in core coal-producing countries,viz.China,USA,Australia,South Africa,and India related to firedamp and coal dust explosion are critically analysed.Accidents occurred due to explosion after Nationalisation of Coal Mines(1973)in India are listed.Prevention and constructive measures adopted in India are critically analysed with respect to the global mining scenario.Measures like methane credit concept,classification of mines/seams with respect to explosion risk zone,deflagration index;installation of automatic fire warning devices,canopy air curtain technology,explosion-prevention measures,such as fire-retardant materials,inhibitors,extinguishing agent,dust suppressor,and active explosion barrier are discussed in detail to avoid explosion and thereby adhering to zero accident policy due to coal mine explosion. 展开更多
关键词 Firedamp explosion Coal dust explosion Preventive measures constructive measures LEGISLATION
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Study on constructive system of green cave dwelling in Loess Plateau—Interpretation with the “regional gene” theory 被引量:5
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作者 WANG Zhu WEI Qin HE Yong 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第11期1754-1761,共8页
This article reveals the inherent evolution adjusting mechanism of regional architecture by means of considering the concept and method of "regional gene" as the research approach of regional architecture co... This article reveals the inherent evolution adjusting mechanism of regional architecture by means of considering the concept and method of "regional gene" as the research approach of regional architecture construction system, and in the mean- while establishes the "gene database" of regional architecture and optimum technology, on the basis of the principle of sustainable development and scientific evaluation system. In addition, this article chooses the planning of model villages of cave dwellings in Loess Plateau and the construction of ecological cave dwellings for case study to prove the feasibility of the research approach. 展开更多
关键词 Regional architecture construction system Regional gene Primordial cave dwellings Green cave dwelling Sus tainable development
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A DATA MINING METHOD BASED ON CONSTRUCTIVE NEURAL NETWORKS 被引量:4
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作者 Wang Lunwen Zhang Ling 《Journal of Electronics(China)》 2007年第1期133-137,共5页
In this letter,Constructive Neural Networks (CNN) is used in large-scale data mining. By introducing the principle and characteristics of CNN and pointing out its deficiencies,fuzzy theory is adopted to improve the co... In this letter,Constructive Neural Networks (CNN) is used in large-scale data mining. By introducing the principle and characteristics of CNN and pointing out its deficiencies,fuzzy theory is adopted to improve the covering algorithms. The threshold of covering algorithms is redefined. "Extended area" for test samples is built. The inference of the outlier is eliminated. Furthermore,"Sphere Neighborhood (SN)" are constructed. The membership functions of test samples are given and all of the test samples are determined accordingly. The method is used to mine large wireless monitor data (about 3×107 data points),and knowledge is found effectively. 展开更多
关键词 Data mining Neural networks constructive Neural Networks (CNN) Wireless monitoring
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Functional and reconstructive urology (part one) 被引量:1
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《Asian Journal of Urology》 2018年第2期55-56,共2页
Dear Colleagues,It is a great honour that the Asian Journal of Urology has agreed to host two special issues on the subject of functional and reconstructive urology and to introduce the first of these editions.In an e... Dear Colleagues,It is a great honour that the Asian Journal of Urology has agreed to host two special issues on the subject of functional and reconstructive urology and to introduce the first of these editions.In an era when technology has come to the fore in urological practice with new developments(not only in terms of the equipment used to facilitate minimally invasive surgery but also developments such as the robot which have revolutionised access to laparoscopic surgery),it is very important to realise that functional and reconstructive urology still remains an important cornerstone of urological practice. 展开更多
关键词 SURGERY CORNERS constructive
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Protective and Constructive Strategies of Rural Landscape Elements in Local Landscape Planning 被引量:1
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作者 HU Yixiao LIANG Ke 《Journal of Landscape Research》 2018年第4期25-29,34,共6页
As a carrier of traditional techniques and local culture, local landscape contains profound theofies of garden aesthetics and landscape ecology. Creating a local landscape is not only important to modem urban ... As a carrier of traditional techniques and local culture, local landscape contains profound theofies of garden aesthetics and landscape ecology. Creating a local landscape is not only important to modem urban landscape design and utban planning, but also an. important part of the construction of current distinctive towns. Based on the analysis of the application of native landscape elements in urban gardens, the research points out the innovative design and application of the local landscape elements. Moreover it uses the artistic expression techniques of extracting the native landscape elements into the garden landscape as the entry point, and analyzes the designing principle and planning key points in die ptocess of creating a local landscape of the cultural square park in charactenstic towns, providing constructing and protecting strategies for creating a landscape of rural landscapes in China's landscape planning. 展开更多
关键词 Local landscape Garden planning Expression techniques construction strategies
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THE PRINCIPAL CONSTRUCTIVE PROCESS OF UNIT CELL IN Bi-BASED SUPERCONDUCTORS
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作者 Gao Xlaohui Gao De +1 位作者 Gao Yang Jiang Shufen(Department of Chemistry, Central South University of Technology, Changsha, 410083, China ) 《Journal of Central South University》 SCIE EI CAS 1995年第2期1-7,共7页
In this paper, 2201 and 2212 phases as the corresponding precursor of forming 2212 and 2223 phases are discussed,and the constructive process of unit cell of 2201 phase is ascertained by XRD and chemical kinetics me... In this paper, 2201 and 2212 phases as the corresponding precursor of forming 2212 and 2223 phases are discussed,and the constructive process of unit cell of 2201 phase is ascertained by XRD and chemical kinetics method. Subsequently, the process of 221 展开更多
关键词 Bi-based SUPERCONDUCTING PHASES reactional PROCESS construction of unit CELL
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Neglect and Constructive Disorder
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作者 施琪嘉 冯建华 +1 位作者 杨敏 常丽英 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1998年第3期190-192,共3页
A 61 year-old right handed man, who suffered from right cerebral infarction with evidences of visual-spatial neglect and constructive disorder, was reported. When copying simple geometric designs, he omitted to copy f... A 61 year-old right handed man, who suffered from right cerebral infarction with evidences of visual-spatial neglect and constructive disorder, was reported. When copying simple geometric designs, he omitted to copy figures on the left side of the page; he tended to bisect the line to the right of the line's real center; after memorizing the familiar pictures he mainly mentioned the pictures on the right side of the page; when copying the 'Rey Complex' he also ignored the structures on the left side. The relations of the neglect and construction disorder are discussed. 展开更多
关键词 NEGLECT constructive apraxia visual-spatial disorder
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Highly efficient four-wave mixing induced by quantum constructive interference in rubidium vapour
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作者 王刚 薛艳 +2 位作者 崔淬砺 曲艺 高锦岳 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期228-231,共4页
We demonstrate efficient four-wave mixing with an intensity conversion efficiency of nearly 100% in theory without considering the Doppler-broadening effect in a four-level double-A system of hot 87Rb gas. The corresp... We demonstrate efficient four-wave mixing with an intensity conversion efficiency of nearly 100% in theory without considering the Doppler-broadening effect in a four-level double-A system of hot 87Rb gas. The corresponding experimental value of about 73% was reported in our earlier work under the same conditions. This dramatic efficiency is critically dependent on the constructive interference between two four-wave mixing processes relevant to the internally generated four-wave mixing signal. 展开更多
关键词 four-wave mixing quantum constructive interference
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Robotic reconstructive surgery: The time has arrived
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作者 Brian W.Chao 《Asian Journal of Urology》 CSCD 2024年第3期339-340,F0002,共3页
Thank you to the Asian Journal of Urology(AJU)for the honor of allowing me to be the vip editor for this special focus section on robotic urinary tract reconstruction.This topic has been a large focus for me in my c... Thank you to the Asian Journal of Urology(AJU)for the honor of allowing me to be the vip editor for this special focus section on robotic urinary tract reconstruction.This topic has been a large focus for me in my career;in my pursuit of knowledge in this new sub-field of urology,I have been so fortunate to have met so many talented surgeons who share a similar passion.The urinary tract spans a large anatomical region,and due to the large variety of conditions that affect it,an endless variety of functional and structural urologic problems can arise.Urologists have always been adept surgeons capable of operating in various anatomical spaces and have embraced technological innovation.Historically,the trend has moved from open surgery to endoscopic treatment;however,many patients with reconstructive needs remain untreated or sub-optimally managed. 展开更多
关键词 SURGERY constructive EDITOR
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Greedy Constructive Procedure-Based Hybrid Differential Algorithm for Flexible Flow shop Group Scheduling
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作者 郑永前 于萌萌 谢松杭 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期577-582,共6页
Aiming at the flexible flowshop group scheduling problem,taking sequence dependent setup time and machine skipping into account, a mathematical model for minimizing makespan is established,and a hybrid differential ev... Aiming at the flexible flowshop group scheduling problem,taking sequence dependent setup time and machine skipping into account, a mathematical model for minimizing makespan is established,and a hybrid differential evolution( HDE) algorithm based on greedy constructive procedure( GCP) is proposed,which combines differential evolution( DE) with tabu search( TS). DE is applied to generating the elite individuals of population,while TS is used for finding the optimal value by making perturbation in selected elite individuals. A lower bounding technique is developed to evaluate the quality of proposed algorithm. Experimental results verify the effectiveness and feasibility of proposed algorithm. 展开更多
关键词 FLEXIBLE flowshop group scheduling HYBRID DIFFERENTIAL evolution(HDE) ALGORITHM GREEDY constructive procedure(GCP) lower bound
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Open TBM Tunnel Intelligent Construction Technology 被引量:2
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作者 LIU Yongsheng CHEN Qiao +4 位作者 ZHANG Hepei LI Shu′ao LIN Chungang YIN Long LI Mengyu 《隧道建设(中英文)》 北大核心 2025年第4期816-833,I0025-I0042,共36页
To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development... To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development.This involved exploring the deep integration of next-generation artificial intelligence technologies,such as sensing technology,automatic control technology,big data technology,deep learning,and machine vision,with key operational processes,including TBM excavation,direction adjustment,step changes,inverted arch block assembly,material transportation,and operation status assurance.The results of this integration are summarized as follows.(1)TBM key excavation parameter prediction algorithm was developed with an accuracy rate exceeding 90%.The TBM intelligent step-change control algorithm,based on machine vision,achieved an image segmentation accuracy rate of 95%and gripper shoe positioning error of±5 mm.(2)An automatic positioning system for inverted arch blocks was developed,enabling real-time perception of the spatial position and deviation during the assembly process.The system maintains an elevation positioning deviation within±3 mm and a horizontal positioning deviation within±10 mm,reducing the number of surveyors in each work team.(3)A TBM intelligent rail transportation system that achieves real-time human-machine positioning,automatic switch opening and closing,automatic obstacle avoidance,intelligent transportation planning,and integrated scheduling and command was designed.Each locomotive formation reduces one shunter and improves comprehensive transportation efficiency by more than 20%.(4)Intelligent analysis and prediction algorithms were developed to monitor and predict the trends of the hydraulic and gear oil parameters in real time,enhancing the proactive maintenance and system reliability. 展开更多
关键词 TUNNEL open TBM intelligent construction deep learning machine vision
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Fast,Exact and Robust Set Operations on Polyhedrons Using Localized Constructive Solid Geometry Trees
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作者 Ping Lu Xudong Jiang +2 位作者 Wei Lu Ran Wei Bin Sheng 《ZTE Communications》 2015年第3期57-66,共10页
Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel... Regularized Boolean operations have been widely used in 3D modeling systems. However, evaluating Boolean operations may be quite numerically unstable and time consuming, especially for iterated set operations. A novel and unified technique is proposed in this paper for computing single and iterated set operations efficiently, robustly and exactly. An adaptive octree is combined with a nested constructive solid geometry (CSG) tree by this technique. The intersection handling is restricted to the cells in the octree where intersection actually occurs. Within those cells, a CSG tree template is instanced by the surfaces and the tree is converted to planebased binary space partitioning (BSP) for set evaluation; Moreover, the surface classification is restricted to the ceils in the octree where the surfaces only come from a model and are within the bounding-boxes of other polyhedrons. These two ways bring about the efficiency and scalability of the operations, in terms of runtime and memory. As all surfaces in such a cell have the same classification relation, they are classified as a whole. Robustness and exactness are achieved by integrating plane-based geometry representation with adaptive geometry predicate technique in intersection handling, and by applying divide-and-conquer arithmetic on surface classification. Experimental results demonstrate that the proposed approach can guarantee the robustness of Boolean computations and runs faster than other existing approaches. 展开更多
关键词 Boolean operations polyhedrons constructive solid geometry binary space partitioning tree
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Constructive Texture Steganography Based on Compression Mapping of Secret Messages
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作者 Fengyong Li Zongliang Yu Chuan Qin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第7期393-410,共18页
This paper proposes a new constructive texture synthesis steganographic scheme by compressing original secret messages.First,we divide the original message into multiple bit blocks,which are transferred to decimal val... This paper proposes a new constructive texture synthesis steganographic scheme by compressing original secret messages.First,we divide the original message into multiple bit blocks,which are transferred to decimal values and compressed into small decimal values by recording their interval sign characters.Then,a candidate pattern is generated by combining the given source pattern and boundary extension algorithm.Furthermore,we segment the candidate pattern into multiple candidate patches and use affine transformation algorithm to locate secret positions on a blank canvas,which are used to hide the sign characters by mapping the candidate patches.Finally,we select the candidate patches with minimal mean square error to represent secret bits to generate stego image by image quilting.Extensive experiments demonstrate that compared with existing texture steganographic methods,our method has a better visual quality,higher embedding capacity and security performance,while maintaining strong anti-steganalysis capability. 展开更多
关键词 constructive steganography texture synthesis compression mapping PATCH
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