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STUDY ON THE FRAMEWORK SYSTEM OF DIGITAL AGRICULTURE 被引量:9
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作者 LIANGYong LUXiu-shan +2 位作者 ZHANGDe-gui LIANGFu RENZhi-bo 《Chinese Geographical Science》 SCIE CSCD 2003年第1期15-19,共5页
China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put f... China is a great agricultural country with large population, limited soilresources and traditional farming mode, so the central government has been attaching greatimportance to the development of agriculture and put forward a new agricultural technologyrevolution ― the transformation from traditional agriculture to modern agriculture and fromextensive farming to intensive farming. Digital agriculture is the core of agriculturalinformatization. The enforcement of digital agriculture will greatly promote agricultural technologyrevolution, two agricultural transformations and its rapid development, and enhance China'scompetitive power after the entrance of WTO. To carry out digital agriculture, the frame system ofdigital agriculture is required to be studied in the first place. In accordance with the theory andtechnology of digital earth and in combination with the agricultural reality of China, this articleoutlines the frame system of digital agriculture and its main content arid technology support. 展开更多
关键词 digital agriculture framework system 3S technology spatial data
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Recent advances in zeolitic imidazolate frameworks as drug delivery systems for cancer therapy
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作者 Yuhan Wang Yixin Tang +4 位作者 Lei Guo Xi Yang Shanli Wu Ying Yue Caina Xu 《Asian Journal of Pharmaceutical Sciences》 2025年第1期94-118,共25页
Biological nanotechnologies based on functional nanoplatforms have synergistically catalyzed the emergence of cancer therapies.As a subtype of metal-organic frameworks(MOFs),zeolitic imidazolate frameworks(ZIFs)have e... Biological nanotechnologies based on functional nanoplatforms have synergistically catalyzed the emergence of cancer therapies.As a subtype of metal-organic frameworks(MOFs),zeolitic imidazolate frameworks(ZIFs)have exploded in popularity in the field of biomaterials as excellent protective materials with the advantages of conformational flexibility,thermal and chemical stability,and functional controllability.With these superior properties,the applications of ZIF-based materials in combination with various therapies for cancer treatment have grown rapidly in recent years,showing remarkable achievements and great potential.This review elucidates the recent advancements in the use of ZIFs as drug delivery agents for cancer therapy.The structures,synthesis methods,properties,and various modifiers of ZIFs used in oncotherapy are presented.Recent advances in the application of ZIF-based nanoparticles as single or combination tumor treatments are reviewed.Furthermore,the future prospects,potential limitations,and challenges of the application of ZIF-based nanomaterials in cancer treatment are discussed.We except to fully explore the potential of ZIF-based materials to present a clear outline for their application as an effective cancer treatment to help them achieve early clinical application. 展开更多
关键词 Metal-organic frameworks(MOFs) Zeolitic imidazolate frameworks(ZIF-8) ZIF-based nanoparticles Drug delivery Cancer treatment
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Research on the framework of the cultural heritage digitalization standards system
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作者 Huang Jing Yu Tianxiu +1 位作者 Liu Jianyu Qu Liang 《China Standardization》 2025年第4期60-63,共4页
The standards system for cultural heritage digitalization aims to build a clear and logically rigorous framework to guide the development and revision of relevant standards.This system enhances the scientific,systemat... The standards system for cultural heritage digitalization aims to build a clear and logically rigorous framework to guide the development and revision of relevant standards.This system enhances the scientific,systematic,and practical aspects of cultural heritage digitalization.This paper comprehensively analyzes the current status and needs of cultural heritage digitalization and standardization.It further examines the methods used to construct the standards system.Through comparative analysis,it establishes a lifecycle-based framework for cultural heritage.This framework accounts for the unique characteristics of cultural heritage and systematically integrates key processes such as collection,processing,storage,transmission,and utilization of data.The standards system is divided into six sections:general,data,information,knowledge,intelligence,and application.Based on the current digitalization efforts,this paper proposes key standardization directions for each section.This framework ensures the integrity and consistency of data throughout the digitalization process.It also supports the application of intelligent technologies in cultural heritage conservation,contributing to the sustainable preservation and utilization of cultural heritage data. 展开更多
关键词 cultural heritage digitalization standards system data lifecycle framework
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Ecological Security Assessment and Risk Management Framework for Recycled Water Systems in Landscape Hydration
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作者 Xinmiao Wang 《Journal of Architectural Research and Development》 2025年第2期28-31,共4页
Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain ... Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain underexplored.This study aims to establish a multidimensional ecological safety evaluation framework for reclaimed water replenishment systems and propose hierarchical risk prevention strategies.By integrating ecotoxicological assays(algae growth inhibition,Daphnia behavioral anomalies,zebrafish embryo toxicity),multimedia exposure modeling,and Monte Carlo probabilistic simulations,the risk contributions and spatial heterogeneity of typical pollutants are quantitatively analyzed.Results revealed that sulfamethoxazole(RQ=2.3)and diclofenac(RQ=1.8)posed high ecological risks,with their effects nonlinearly correlated with hydraulic retention time(HRT<3 days)and nutrient loading(TN>1.2 mg/L).A three-tier risk prevention system was developed based on the“source-pathway-receptor”framework:ozone-activated carbon pretreatment achieved 85%removal efficiency for pharmaceutical contaminants,ecological floating beds enhanced nitrogen and phosphorus retention by 40%-60%,and hydraulic regulation(flow velocity>0.1 m/s)effectively suppressed pathogen proliferation.The innovation of this study lies in establishing a chemical-biological-hydrological coupled risk quantification model for reclaimed water reuse scenarios.The hierarchical prevention standards have been incorporated into local reclaimed water management regulations,providing a scientific foundation and technical paradigm for sustainable landscape water replenishment. 展开更多
关键词 Recycled water systems Landscape hydration Ecological security assessment Risk management framework
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A Contrastive Analysis of English and Chinese Intonation Systems: An Auto- Segmental Metrical Framework
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作者 Qingbo Tian Ngee Thai Yap +1 位作者 Chwee Fang Ng Yasir Yahya 《Chinese Journal of Applied Linguistics》 2025年第3期366-400,480,481,共37页
Intonation refers to the use of supra-segmental features to convey pragmatic meanings at the sentence level in a linguistically structured way.The difference in intonation between the native language and a foreign lan... Intonation refers to the use of supra-segmental features to convey pragmatic meanings at the sentence level in a linguistically structured way.The difference in intonation between the native language and a foreign language may influence second language learners’acquisition of intonation.The purpose of this study is to explore the similarities and differences at the level of phonological representation between English and Chinese intonation systems.This study investigated English and Chinese intonation systems,respectively,from both form and meaning under the Auto-Segmental Metrical framework by referring to previous studies and illustrating examples.The results showed that in terms of form,there were notable differences in the structural elements and their inventories between the intonation systems of English and Chinese.In terms of meaning,assertions were represented by different structural elements in English and Chinese intonation systems;the types of structural elements in English intonation possessed the capability to convey complex and subtle meanings,contrasting with the comparatively simpler nature of Chinese intonation.The results reveal that Chinese EFL learners demonstrate considerable difficulties in the production of the structural elements of English intonation and their combinations due to L1 intonation interference. 展开更多
关键词 acquisition of L2 intonation auto-segmental metrical framework Chinese intonation cross-linguistic effects English intonation
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Construction of a Teaching System Through School-enterprise Collaboration in an Integration and Innovation Framework:A Case Study of the Internet of Things Specialization in the Software Engineering Program
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作者 Jing Tang Donglai Fu +2 位作者 Jun Hong Guoyu Qi Yan Qiang 《计算机教育》 2025年第3期41-47,共7页
The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engin... The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engineering into IoT engineering education remains underexplored.To address this gap,the School of Software at North University of China,in collaboration with QST Innovation Technology Group Co.,Ltd.(QST),has developed an innovative educational mechanism.This initiative focuses on the software engineering IoT track and optimizes the teaching process through the outcome-based education(OBE)concept.It incorporates military-industrial characteristics,introduces advanced information and technology curricula,and enhances laboratory infrastructure.The goal is to cultivate innovative talents with unique capabilities,thereby fostering the comprehensive development and application of IoT technology. 展开更多
关键词 Software engineering IoT track School-enterprise collaboration Integration and innovation framework Outcome-based education
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Research on multi-view collaborative detection system for UAV swarms based on Pix2Pix framework and BAM attention mechanism
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作者 Yan Ding Qingxin Cao +2 位作者 Bozhi Zhang Peilin Li Zhongjiao Shi 《Defence Technology(防务技术)》 2025年第4期213-226,共14页
Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,an... Drone swarm systems,equipped with photoelectric imaging and intelligent target perception,are essential for reconnaissance and strike missions in complex and high-risk environments.They excel in information sharing,anti-jamming capabilities,and combat performance,making them critical for future warfare.However,varied perspectives in collaborative combat scenarios pose challenges to object detection,hindering traditional detection algorithms and reducing accuracy.Limited angle-prior data and sparse samples further complicate detection.This paper presents the Multi-View Collaborative Detection System,which tackles the challenges of multi-view object detection in collaborative combat scenarios.The system is designed to enhance multi-view image generation and detection algorithms,thereby improving the accuracy and efficiency of object detection across varying perspectives.First,an observation model for three-dimensional targets through line-of-sight angle transformation is constructed,and a multi-view image generation algorithm based on the Pix2Pix network is designed.For object detection,YOLOX is utilized,and a deep feature extraction network,BA-RepCSPDarknet,is developed to address challenges related to small target scale and feature extraction challenges.Additionally,a feature fusion network NS-PAFPN is developed to mitigate the issue of deep feature map information loss in UAV images.A visual attention module(BAM)is employed to manage appearance differences under varying angles,while a feature mapping module(DFM)prevents fine-grained feature loss.These advancements lead to the development of BA-YOLOX,a multi-view object detection network model suitable for drone platforms,enhancing accuracy and effectively targeting small objects. 展开更多
关键词 Drone swarm systems Reconnaissance and strike Image generation Multi-view detection Pix2Pix framework Attention mechanism
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Single-image super-resolution of gamma-ray imaging system using deep denoiser prior based on plug-and-play framework
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作者 Guo-Guang Li Liang Sheng +6 位作者 Bao-Jun Duan Yang Li Yan Song Zi-Jian Zhu Wei-Peng Yan Dong-Wei Hei Qing-Zi Xing 《Matter and Radiation at Extremes》 2025年第2期56-70,共15页
Gamma-ray imaging systems are powerful tools in radiographic diagnosis.However,the recorded images suffer from degradations such as noise,blurring,and downsampling,consequently failing to meet high-precision diagnosti... Gamma-ray imaging systems are powerful tools in radiographic diagnosis.However,the recorded images suffer from degradations such as noise,blurring,and downsampling,consequently failing to meet high-precision diagnostic requirements.In this paper,we propose a novel single-image super-resolution algorithm to enhance the spatial resolution of gamma-ray imaging systems.A mathematical model of the gamma-ray imaging system is established based on maximum a posteriori estimation.Within the plug-and-play framework,the half-quadratic splitting method is employed to decouple the data fidelit term and the regularization term.An image denoiser using convolutional neural networks is adopted as an implicit image prior,referred to as a deep denoiser prior,eliminating the need to explicitly design a regularization term.Furthermore,the impact of the image boundary condition on reconstruction results is considered,and a method for estimating image boundaries is introduced.The results show that the proposed algorithm can effectively addresses boundary artifacts.By increasing the pixel number of the reconstructed images,the proposed algorithm is capable of recovering more details.Notably,in both simulation and real experiments,the proposed algorithm is demonstrated to achieve subpixel resolution,surpassing the Nyquist sampling limit determined by the camera pixel size. 展开更多
关键词 deep denoiser prior enhance spatial resolution maximum posteriori estimationwithin radiographic diagnosishoweverthe maximum posteriori estimation gamma ray imaging plug play framework recorded images
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Ligand-directed construction of cobalt-oxo cluster-based organic frameworks:Structural modulation,semiconductor,and antiferromagnetic properties
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作者 SHI Jinlian LIU Xiaoru XU Zhongxuan 《无机化学学报》 北大核心 2026年第1期45-54,共10页
Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct... Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24. 展开更多
关键词 semi-rigid carboxylic acid ligands three-dimensional framework tetranuclear cobalt-oxo cluster semiconductor material antiferromagnetic magnetism
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Advances in electrocatalytic and photocatalytic CO_(2)conversion to value-added chemicals using copper-based covalent organic frameworks
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作者 LI Yue LIU Ziqi +7 位作者 FENG Ke LI Yingdan NING Yue SHEN Li LU Jitao MENG Qingguo WANG Min WANG Haiying 《无机化学学报》 北大核心 2026年第1期1-22,共22页
CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organ... CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organic frameworks(COFs)are porous crystalline materials formed by connecting organic monomers through covalent bonds.They have the characteristics of functional diversity and rich chemical properties.Their advantages,such as high porosity,a wide range of visible light absorption,and excellent charge separation efficiency,give them good potential in CO_(2)capture,separation,and conversion.Currently,Cu is a key metal in the catalytic CO_(2)reduction reaction(CO_(2)RR)for the preparation of high-value-added chemicals.The preparation of highly stable and large-pore Cu-based COFs using COFs as an ideal sacrificial template for loading Cu can be used to develop high-performance electrocatalysts and photocatalysts.In this review,we discuss the latest advancements in this field,including the development of various Cu-based COFs and their applications as catalysts for CO_(2)RR.Here,we mainly introduce the synthesis strategies,some important characterization information,and the applications of electrocatalytic and photocatalytic CO_(2)conversion using these previously reported Cu-based COFs. 展开更多
关键词 copper-based covalent organic frameworks CO_(2)reduction reactions electrocatalytic CO_(2)conversion photocatalytic CO_(2)conversion
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Bioinspired Precision Peeling of Ultrathin Bamboo Green Cellulose Frameworks for Light Management in Optoelectronics
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作者 Yan Wang Yuan Zhang +2 位作者 Yingfeng Zuo Dawei Zhao Yiqiang Wu 《Nano-Micro Letters》 2026年第1期474-489,共16页
Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fund... Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics. 展开更多
关键词 Bamboo green Cellulose framework Chemical peeling Optical properties Light management
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Development of a distributed and integratable manufacturing execution system framework 被引量:4
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作者 杨浩 周娜 +1 位作者 朱剑英 罗翔 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期64-69,共6页
Using remote method invocation (RMI) and a distributed object-oriented technique, this paper presents a systematic approach to developing a manufacturing execution system (MES) framework, which is open, modularized, d... Using remote method invocation (RMI) and a distributed object-oriented technique, this paper presents a systematic approach to developing a manufacturing execution system (MES) framework, which is open, modularized, distributed, configurable, interoperable and maintainable. Moreover, the design patterns for the framework .are developed and a variety of functional components are designed by inheriting appropriate patterns. And then an application is constructed by invoking corresponding methods of related components. An MES system implementing the framework and design patterns can be facilely integrated with other manufacturing applications, such as enterprise resource planning (ERP) and floor control system (FCS) . 展开更多
关键词 manufacturing execution system framework design pattern distributed object-oriented remote method invocation
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CAPP Framework System for Concurrent Engineering
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作者 李志忠 王先逵 刘成颖 《Tsinghua Science and Technology》 SCIE EI CAS 1999年第2期52-58,共7页
Difficulty in generalizing and lack of adapt ability are important factors that hamper a computer aided process planning (CAP P) system from being popular and practical. New manufacturing philosophies such as Concur... Difficulty in generalizing and lack of adapt ability are important factors that hamper a computer aided process planning (CAP P) system from being popular and practical. New manufacturing philosophies such as Concurrent Engineering require special characteristic of a CAPP system. Propose d in this paper is a CAPP framework system for Concurrent Engineering (CAPPFS C E) which can meet the requirements of Concurrent Engineering and whose informati on models, function models and decision logic can be customized by users to form various CAPP application systems. Its function requirements are discussed broadly. An architecture for CAPPFS CE is presented. It is based on abstract in formati on models (AIMs) and abstract function models (AFMs). The kernel is formed by cu stomization interpretation, internal process control and decision engine. A new information modeling and system development method, information element method ( IEM), is introduced to build up AIMs, decision engine, and AFMs and then realize a CAPPFS CE. THCAPP SHELL, a CAPPFS CE developed by IEM, is demonstrated. A CAPP system produced by customizing THCAPP SHELL for complex structural parts i n a concurrent engineering environment is shown. 展开更多
关键词 CAPP CAPP adaptability framework system Concurrent Engineering information m odeling
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CONSTRUCTION OF INTEGRATIVE INFORMATION MANAGEMENT SYSTEM FOR RADIATION ONCOLOGY BASED ON IHE-RO FRAMEWORK 被引量:2
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作者 邱学军 戴建荣 +2 位作者 符贵山 黄金带 冒苏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第1期107-111,共5页
How to construct integrative information management system for radiation oncology is a new practice in China based on new technical framework and the profile of integrating the healthcare enterprise in radiation oncol... How to construct integrative information management system for radiation oncology is a new practice in China based on new technical framework and the profile of integrating the healthcare enterprise in radiation oncology (IHE-RO). This paper presents the research progress for constructing the system in the department of the radiation oncology at Cancer Hospital of Chinese Academy of Medical Sciences, and its system diagram based on IHE-RO technical framework, digital imaging and communication in medicine with radiotherapy (DICOM RT) data flow standard, and emphasizes the importance of DICOM RT in constructing the system and describes the generation process of DICOM RT objects. Finally, the related international standards are suggested on RT devices adopted by China State Food and Drug Administration (SFDA) when the system is constructed. 展开更多
关键词 IHE-RO framework RADIOTHERAPY information management
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Porous framework materials for energy&environment relevant applications:A systematic review 被引量:8
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作者 Yutao Liu Liyu Chen +16 位作者 Lifeng Yang Tianhao Lan Hui Wang Chenghong Hu Xue Han Qixing Liu Jianfa Chen Zeming Feng Xili Cui Qianrong Fang Hailong Wang Libo Li Yingwei Li Huabin Xing Sihai Yang Dan Zhao Jinping Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期217-310,共94页
Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and eff... Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and efficiency reinforcement,carbon capture,and pollutant gas treatment is in highly imperious demand.The emerging porous framework materials such as metal–organic frameworks(MOFs),covalent organic frameworks(COFs)and hydrogen-bonded organic frameworks(HOFs),owing to the permanent porosity,tremendous specific surface area,designable structure and customizable functionality,have shown great potential in major energy-consuming industrial processes,including sustainable energy gas catalytic conversion,energy-efficient industrial gas separation and storage.Herein,this manuscript presents a systematic review of porous framework materials for global and comprehensive energy&environment related applications,from a macroscopic and application perspective. 展开更多
关键词 Porous framework materials CATALYSIS SEPARATION Gas storage Carbon neutrality
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A Comprehensive Evaluation Framework of Water-Energy-Food System Coupling Coordination in the Yellow River Basin,China 被引量:8
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作者 YIN Dengyu YU Haochen +3 位作者 LU Yanqi ZHANG Jian LI Gensheng LI Xiaoshun 《Chinese Geographical Science》 SCIE CSCD 2023年第2期333-350,共18页
For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governan... For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governance mechanism that aims at nexus security needs to be urgently established.In this paper,the Yellow River Basin in China with a representative WEF system,was selected as a case.Firstly,a comprehensive framework for WEF coupling coordination was constructed,and the relationship and mechanism between them were analyzed theoretically.Then,we investigated the spatiotemporal characteristics and driving mechanisms of the coupling coordination degree(CCD)with a composite evaluation method,coupling coordination degree model,spatial statistical analysis,and multiscale geographic weighted regression.Finally,policy implications were discussed to promote the coordinated development of the WEF system.The results showed that:1)WEF subsystems showed a significant imbalance of spatial pattern and diversity in temporal changes;2)the CCD for the WEF system varied little and remained at moderate coordination.Areas with moderate coordination have increased,while areas with superior coordination and mild disorder have decreased.In addition,the spatial clustering phenomenon of the CCD was significant and showed obvious characteristics of polarization;and 3)the action of each factor is self-differentiated and regionally variable.For different factors,GDP per capita was of particular importance,which contributed most to the regional development’s coupling coordination.For different regions,GDP per capita,average yearly precipitation,population density,and urbanization rate exhibited differences in geographical gradients in an east-west direction.The conclusion can provide references for regional resource allocation and sustainable development by enhancing WEF system utilization efficiency. 展开更多
关键词 water-energy-food(WEF) comprehensive framework coupling coordination relationship driving mechanism Yellow River Basin China
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A Mandatory Access Control Framework in Virtual Machine System with Respect to Multi-level Security Ⅱ:Implementation 被引量:5
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作者 刘谦 王观海 +2 位作者 翁楚良 骆源 李明禄 《China Communications》 SCIE CSCD 2011年第2期86-94,共9页
This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level securi... This paper is a continuation of our last paper [1] which describes the theory of Virt-BLP model. Based on Virt-BLP model,this paper implements a mandatory access control(MAC) framework applicable to multi-level security(MLS) in Xen. The Virt-BLP model is the theoretical basis of this MAC framework,and this MAC framework is the implementation of Virt-BLP model. Our last paper focuses on Virt-BLP model,while this paper concentrates on the design and implementation of MAC framework. For there is no MAC framework applicable to MLS in virtual machine system at present,our MAC framework fills the blank by applying Virt-BLP model to Xen,which is better than current researches to guarantee the security of communication between virtual machines(VMs) . The experimental results show that our MAC framework is effective to manage the communication between VMs. 展开更多
关键词 virt-BLP model MAC framework multi-level security XEN
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Indicator system and evaluation framework for sustainable development 被引量:3
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作者 ZHAO Jing\|zhu\+1, Johannes Baptist Opschoor\+2 (1. Department of Systems Ecology, Research Center for Eco\|Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2. Economics Faculty, Free University, De Boelelaan 1105, 1081 HV Am 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第4期492-497,共6页
An indicator system of sustainable development was established and an evaluation framework for sustainable development was drawn in this study.
关键词 sustainable development indicator system evaluation framework
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Late Paleozoic Sequence-Stratigraphic Frameworks and Sea Level Changes in Dianqiangui Basin and Its Adjacent Areas with Systematic Revision of Regional Unconformities 被引量:8
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作者 MeiMingxiang MaYongsheng +3 位作者 DengJun MengQingfen YiDinghong LiDonghai 《Journal of China University of Geosciences》 SCIE CSCD 2004年第1期55-68,共14页
The formation process of the Dianqiangui basin, a special basin, occurred after the Caledonian orogeny, in the south of Guizhou, the west of Guangxi and the southeast of Yunnan, experienced three periods: it began ... The formation process of the Dianqiangui basin, a special basin, occurred after the Caledonian orogeny, in the south of Guizhou, the west of Guangxi and the southeast of Yunnan, experienced three periods: it began in the Devonian, persisted in the Carboniferous, and became fiercer in the Permian. Controlled by syndepositional fault-zones, varieties of isolated carbonate platforms, large and small, were developed in the background of a deep-water basin, namely, an inter-platform ditch. And a special paleogeographical Late Paleozoic pattern marked by “platform-basin-hill-trough” was produced in both the Dianqiangui basin and its adjacent areas. Affected by regional tectonic activities and the global changes in the sea level, the platform carbonates and coal measures superimposed each other cyclically on the attached platform. The reef-building on the isolated platform and the margin of the attached platform corresponds to the development of the shale succession in the deep-water basin. All of these elementary characteristics reflect a regular and sophisticated filling succession of the Dianqiangui basin, a result of the dual controls of the regionally tectonic activities and the eustacy. Based on the two elementary features of the third-order sequences, i.e. the regularity of sedimentary-facies succession in space and the simultaneity of environmental changes in time, 25 third-order sequences could be discerned in the Upper Paleozoic strata in the Dianqiangui basin and its adjacent areas. On the basis of the two kinds of facies-changing surfaces and the two kinds of diachronisms in stratigraphic records, the regional Late Paleozoic sequence-stratigraphic framework in the Dianqiangui basin and its adjacent areas can be established. There are two types of facies-changing surfaces and two types of diachronisms in stratigraphic records: the static type, a result of the change in sedimentary facies in space, and the dynamic type, a result of the change in time. These two types of facies-changing surfaces led to the generation of the two types of diachronisms: the diachronism of facies-changing surfaces that was formed by the static facies-changing surfaces, and the diachronism of punctuated surfaces that was formed by the dynamic facies-changing surfaces. The two types of facies-changing surfaces and the two types of diachronisms in stratigraphic records are the key to the establishment of the sequence-stratigraphic framework. The sequence boundaries could be divided geologically into four types: tectonic unconformity, sedimentary unconformity, drowned unconformity and their correlative surfaces. All of these four types can be further grouped into exposed punctuated surfaces and deepened punctuated surfaces. The tectonic unconformity is similar to Type Ⅰ sequence boundary, and the sedimentary unconformity is similar to Type Ⅱ sequence boundary defined by Vail et al.. In terms of sequence stratigraphy, the tectonic unconformities of the Ziyun movement, the Qiangui epeirogeny and the Dongwu revolution as well as the drowned unconformity in the transitional period from the Permian to the Triassic can be systematically defined and their geological characteristics are briefly presented. 展开更多
关键词 sequence-stratigraphic frameworks Late Paleozoic revision of unconformities Dianqiangui basin and its adjacent areas.
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Iron-based metal-organic framework as a dual cooperative release system for enhanced vascularization and bone regeneration 被引量:3
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作者 Chang Xu Yue Kang +3 位作者 Shiqiang Guan Xufeng Dong Daqing Jiang Min Qi 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第5期475-479,共5页
Vascularization and bone regeneration are closely related in the process of bone remodeling,and designing a bioactive scaffold with pro-angiogenic and osteogenic properties may accelerate the repair of bone defects.In... Vascularization and bone regeneration are closely related in the process of bone remodeling,and designing a bioactive scaffold with pro-angiogenic and osteogenic properties may accelerate the repair of bone defects.In this work,an iron-based metal-organic framework(MIL-88)was developed as a carrier for loading a pro-angiogenic small molecular drug(dimethyloxallyl glycine,DMOG),and then embedded into the PLGA nanofibrous scaffolds to repair cranial defects in rats.Imaging and histological evaluation indicated that PLGA/MIL@D scaffold markedly enhanced vascularization and bone regeneration in vivo.Moreover,in vitro assay showed that co-delivery system significantly promoted angiogenesis by stimulating endothelial cell migration,tube formation,and enhanced osteogenesis by promoting expression of osteoblast related proteins.In addition,PLGA/MIL@D scaffold promotes angiogenesis by activating the hypoxia-inducible factor-1(HIF-1)/vascular endothelial growth factor(VEGF)signaling pathway.Altogether,this bioactive PLGA/MIL@D scaffold can combine angiogenesis with osteogenesis,and will be a bright strategy for the repair of bone defects. 展开更多
关键词 OSTEOGENESIS ANGIOGENESIS DMOG Metal-organic framework Bone regeneration
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