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Optimizing a multimedia model to assess the differential roles of crops and natural vegetation in the fate of PAHs
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作者 Chao Su Danfeng Zheng +7 位作者 Wenlei Chen Kifayatullah Khan Hong Zhang Shuai Song Ruoyu Liang Xiaoyu Zhang Yong Liu Xianghui Cao 《Journal of Environmental Sciences》 2026年第1期413-423,共11页
Vegetation plays an important role in the environmental transport behavior of organic pollutants,however,the different roles of crops and natural vegetation have been ignored in most previous studies.In this study,we ... Vegetation plays an important role in the environmental transport behavior of organic pollutants,however,the different roles of crops and natural vegetation have been ignored in most previous studies.In this study,we developed the BETR-Urban-Rural-Veg model to quantitatively evaluate the influences of both natural vegetation and crops on the multimedia transport processes of Phenanthrene(PHE)and Benzo(a)pyrene(BaP)in mainland of China.The geographic distribution of polycyclic aromatic hydrocarbon(PAH)emissions and concentrations were consistent,displaying higher levels in northern China while lower levels in southern China.Under seasonal simulations,for both natural vegetation and crops,PAH concentrations in winter and spring were 1.5 to 27-fold higher than in summer and autumn,especially for PHE.Owing to the higher leaf area index(LAI)of natural vegetation and harvesting of crops,the filter and sequestration effect of natural vegetation was stronger than crops,while the seasonal changes of PAH concentrations in crops were more significant than natural vegetation.Temperature,precipitation rates and LAI might have important influences on seasonal concentrations and overall persistence of PAHs.PHE was more sensitive to the impacts of seasonal environmental parameters.Under different landscape scenarios,average annual PAH concentrations in natural vegetation were always a little higher than those in crops,and the overall persistence of BaP was greatly affected increasing by 15.15%-16.47%.This improved model provides a useful tool for environmental management.The results of this study are expected to support land use plans and decision-making in China's mainland. 展开更多
关键词 multimedia fate model Natural vegetation CROPS Seasonal variabilities Landscape scenarios
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Urban and rural transport of semivolatile organic compounds at regional scale: A multimedia model approach 被引量:9
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作者 Shuai Song Chao Su +3 位作者 Yonglong Lu Tieyu Wang Yueqing Zhang Shijie Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期228-241,共14页
Urban areas are generally regarded as major sources of some semivolatile organic compounds and other persistent organic pollutants(POPs) to the surrounding regions. Huge differences in contaminant emissions between ... Urban areas are generally regarded as major sources of some semivolatile organic compounds and other persistent organic pollutants(POPs) to the surrounding regions. Huge differences in contaminant emissions between urban and rural areas directly affect their fate in environmental media. Little is known about POPs behavior between urban and rural areas at a regional scale. A spatially resolved Berkeley-Trent-Urban-Rural Fate Model(BETR-UR) was designed by coupling land cover information to simulate the transport of POPs between urban and rural areas, and the Bohai Rim was used as a case study to estimate Polycyclic Aromatic Hydrocarbon(PAH) fate. The processes of contaminant fate including emission, inter-compartmental transfer, advection and degradation in urban and rural areas were simulated in the model. Simulated PAH concentrations in environmental media of urban and rural areas were very close to measured values. The model accuracy was highly improved, with the average absolute relative error for PAH concentrations reduced from 37% to 3% compared with unimproved model results. PAH concentrations in urban soil and air were considerably higher than those in rural areas. Sensitivity analysis showed temperature was the most influential parameter for Phen rather than for Bap, whose fate was more influenced by emission rate, compartment dimension, transport velocity and chemical persistence. Uncertainty analysis indicated modeled results in urban media had higher uncertainty than those in rural areas due to larger variations of emissions in urban areas. The differences in urban and rural areas provided us with valuable guidance on policy setting for urban–rural POP control. 展开更多
关键词 Land use PAH fate Regional scale multimedia model
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An enhanced environmental multimedia modeling system based on fuzzy-set approach: II. Model validation and application
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作者 Rongrong ZHANG Chesheng ZHAN +1 位作者 Xiaomeng SONG Baolin LIU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第6期1025-1035,共11页
Part I of this study develops an enhanced environmental multimedia modeling system (EMMS) based on fuzzy-set approach. Once the model development is complete, the composite module and the entire modeling system need... Part I of this study develops an enhanced environmental multimedia modeling system (EMMS) based on fuzzy-set approach. Once the model development is complete, the composite module and the entire modeling system need to be tested and validated to ensure that the model can simulate natural phenomena with reasonable and reliable accuracy. The developed EMMS is first tested in a complete case study. And then verification results are conducted to compare with extensively researched litera- ture data. In the third step, the data from an experimental landfill site is used for a pilot-scale validation. The comparisons between EMMS outputs and the literature data indicate that the EMMS can perform accurate modeling simulation. The modules of EMMS could support the entire environmental multimedia modeling system. Further field-scale validation is finished. The results are satisfactory. Most of the modeling yields closely match the monitoring data collected from sites. In addition, with the aid of fuzzy-set approach, EMMS can be a reliable and powerful tool to address the complex environmental multimedia pollution problems and provide an extensive support for decision makers in managing the contaminated environmental systems. 展开更多
关键词 environmental multimedia modelling system fuzzy-set approach APPLICATION model validation uncer-tainty analysis
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An enhanced environmental multimedia modeling system based on fuzzy-set approach: I. Theoretical framework and model development
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作者 Chesheng ZHAN Rongrong ZHANG +1 位作者 Xiaomeng SONG Baolin LIU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第3期494-505,共12页
Multimedia environmental modeling is extremely complex due to the intricacy of the systems with the consideration of many related factors. Traditional environmental multimedia models (EMMs) are usually based on one-... Multimedia environmental modeling is extremely complex due to the intricacy of the systems with the consideration of many related factors. Traditional environmental multimedia models (EMMs) are usually based on one-dimensional and first-order assumptions, which may cause numerical errors in the simulation results. In this study, a new user-friendly fuzzy-set enhanced environmental multimedia modeling system (FEEMMS) is developed, and includes four key modules: an air dispersion module, a polluting source module, an unsaturated zone module, and a groundwater module. Many improvements over previous EMMs have been achieved through dynamically quantifying the intermedia mass flux; incorporating fuzzy-set approach into environmental multimedia modeling system (EMMS); and designing a user-friendly graphic user interface (GUI). The developed FEEMMS can be a useful tool in estimating the timevarying and spatial-varying chemical concentrations in air, soil, and groundwater; characterizing the potential risk to human health presented by contaminants released from a contaminated site; and quantifying the uncertainties associated with modeling systems and subsequently providing robustness and flexibility for the remediationrelated decision making. 展开更多
关键词 environmental multimedia modelling fuzzyset approach theoretical framework environmental protection
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Interactive Multimedia Synchronization Model Based on Petri Nets 被引量:2
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作者 WANG Zhiqiang PENG Xiaogang JI Zhen 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1019-1023,共5页
The multimedia synchronization is used to coordinate the timing of each multimedia object in the multimedia system. After studying different multimedia synchronization systems that have been published, an Interactive ... The multimedia synchronization is used to coordinate the timing of each multimedia object in the multimedia system. After studying different multimedia synchronization systems that have been published, an Interactive Synchronization multimedia based on Petri Nets model (ISPN) is proposed in this paper. The system is capable of describing the dynamic timing actions of multimedia objects vividly as well as controlling them interactively to maintain the system level synchronization balance. 展开更多
关键词 Petri net multimedia synchronization model ISPN
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DATA MODEL FOR MULTIMEDIA DATABASE SYSTEM NHMDB BASED ON NF^2 DATA MODEL
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作者 Guo Hongying Lin Junhai Tian Canghai (Department of Comprter Science and Engineering ,NUAA 29 Yudao Street,Nanjing 210016,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第2期210-214,共5页
An approach to implementing the multimedia database system NHMDB based on NF2(Non-First-Normal-Form) data model is presented. This approach is easily implemented because NF2 structure can efficiently store various med... An approach to implementing the multimedia database system NHMDB based on NF2(Non-First-Normal-Form) data model is presented. This approach is easily implemented because NF2 structure can efficiently store various media data such as formatted data, text,graphics, image and voice. The main idea is to expand conceptual schema to maintain the consistency of tbreelevel schema in system NHMDB. We developed, implemented and experimented the storage structure and the multimedia data representation by an object identifier.implementation techniques are also discussed. 展开更多
关键词 DATABASE APPROXIMATION DATA model multimedia
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Temporal Models for Multimedia Synchronization
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作者 李明禄 《High Technology Letters》 EI CAS 1997年第2期37-41,共5页
This paper provides a survey of selection of most common existing temporal models for multimedia synchronization, which are based on CSP, CCS, path expressions, and Petri net. Multimedia refers to the integrated gener... This paper provides a survey of selection of most common existing temporal models for multimedia synchronization, which are based on CSP, CCS, path expressions, and Petri net. Multimedia refers to the integrated generation, representation, processing, storage, and dissemination of information expressed in multiple time dependent and time independent media such as data, text, graphics, images, audio, and video. Synchronization assures a temporal order of events, which is a well-studied topic in the area of operating systems, parallel programming languages, and database technology. 展开更多
关键词 multimedia SYNCHRONIZATION TEMPORAL modelS CONCURRENT THEORY
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QoE Modeling and Applications for Multimedia Systems
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作者 Wenjun Zeng Weisi Lin 《ZTE Communications》 2013年第1期1-1,共1页
Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience (QoE) involves subjective perception, user behavior... Ireproving the quality and experience perceived by the user is fundamental when de- veloping multimedia technologies, products, and services. Quality of experience (QoE) involves subjective perception, user behavior and needs, appropriateness, con- text, and usability of delivered content. Modeling QoE is critical for enhancing QoE in various nmhimedia applications. In this special issue, 展开更多
关键词 QoE modeling and Applications for multimedia Systems DTV
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多媒体融合教学模式在风景园林规划设计课程实验教学中的应用
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作者 强薇 王海燕 +1 位作者 王利 马燕 《中国现代教育装备》 2026年第3期105-106,119,共3页
本文针对风景园林规划设计课程实验教学,提出多媒体融合教学模式。该模式通过VR、3D、CAD等技术手段,构建动态化、情景化的教学场景,强化以学生为中心的理念。实践表明,该模式能够显著提升学生的设计创新能力、实践操作水平及课程参与度。
关键词 多媒体融合 教学模式 风景园林规划设计 实验教学
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Source emissions and climate change impacts on the multimedia transport and fate of persistent organic pollutants,Chaohu watershed,eastern China 被引量:3
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作者 Xianghui Cao Shouliang Huo +4 位作者 Hanxiao Zhang Jiaqi Zheng Zhuoshi He Chunzi Ma Shuai Song 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第11期15-25,共11页
Emission intensity and climate change control the transport flux and fate of persistent organic pollutants(POPs)inmultiple environmental compartments.This study applied amultimedia model(BETR model)to explore alternat... Emission intensity and climate change control the transport flux and fate of persistent organic pollutants(POPs)inmultiple environmental compartments.This study applied amultimedia model(BETR model)to explore alternations in the spatio-temporal trends of concentrations and transport flux of benzopyrene(BaP),phenanthrene(Phe),perfluorooctane sulfonates(PFOS)and polychlorinated biphenyls(PCBs)in the Chaohu watershed,located in the lower reaches of the Yangtze River,China in response to changes in source emissions and climate.The potential historic and future risks of these pollutants also were assessed.The results suggest that current trends in concentrations and transport were similar to that of their emissions between 2005 and 2018.During the next 100 years,temporal trends and spatial patterns were not predicted to change significantly,which is consistent with climate change.Based on sensitivity and correlation analyses,climate change had significant effects on multi-media concentrations and transport fluxes of BaP,Phe,PFOS and PCBs,and rainfall intensity was the predominant controlling factor.Risk quotients(RQs)of BaP and Phe-in soil increased from 0.42 to 0.95 and 0.06 to 0.35,respectively,from 2005 to 2090,indicating potential risks.The RQs of the other examined contaminants exhibited little potential risk in soil,water,or sediment.Based on spatial patterns,it was inferred that the ecosystem around Lake Chaohu is the most at risk.The study provides insights needed for local pollution control of POPs in the Chaohu watershed.In addition,the developed approach can be applied to other watersheds world-wide. 展开更多
关键词 Climate change POP emissions multimedia model Contaminant transport Risk assessment
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CAPABILITIES OF MULTIMEDIA GIS 被引量:2
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作者 郑扣根 潘云鹤 《Chinese Geographical Science》 SCIE CSCD 1999年第2期63-69,共7页
A geographical information system (GIS) is used to capture, store, retrieve, analyzed and display the spatial (locationally defined) data. In contrast to traditional GIS, multimedia GIS is not only able to collect, an... A geographical information system (GIS) is used to capture, store, retrieve, analyzed and display the spatial (locationally defined) data. In contrast to traditional GIS, multimedia GIS is not only able to collect, analyze and store the data in traditional formats i.e. text, images (pictures) and graphs but also audio (sound), animations and video (moving pictures) as well. In this paper the advantages of multimedia GIS over traditional GIS are explained. Multimedia GIS is fully capable of providing services to both technical and non technical users and users of multimedia GIS can retain more knowledge than users of traditional GIS. It can be applied to various fields such as tourism, environment, education etc. Some implementation issues such as data updating, information retrieval and data compression etc. are also addressed. Finally, future development of MMGIS (using new multimedia technologies such as Virtual Reality and Virtual Reality Modeling Language) is discussed. 展开更多
关键词 GIS multimedia GIS multimedia DATABASE VIRTUAL REALITY VIRTUAL REALITY modeling LANGUAGE
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Quality Requirements for Multimedia Interactive Informative Systems
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作者 Sylviane Levy Fernando Gamboa 《Journal of Software Engineering and Applications》 2013年第8期416-425,共10页
Multimedia Interactive Informative Systems (MIIS) are software applications resulting from the convergence of multiples technologies such as audiovisual, computing and communication. They aim to transmit information t... Multimedia Interactive Informative Systems (MIIS) are software applications resulting from the convergence of multiples technologies such as audiovisual, computing and communication. They aim to transmit information to a large, diverse and dispersed public. As with other mass media, the fulfillment of MIIS goals depends largely on the quality of communication between the system and end users. Therefore, those systems should be developed in order to ensure that this quality requirement is satisfied. If MIIS are constructed according to usual software engineering practices, the analysis discipline of the development process includes requirements identification and specification;however, these techniques are focused on functional requirements, and they do not give much importance to non-functional requirements. In this paper, we propose a development process based on the production of videogames which has two different phases: preproduction and production. The first phase, corresponding to requirements identification, derives into the concept of system. In order to translate this concept into a specification, we propose the use of new communicational attributes and a MIIS metamodel. The establishment of MIIS non-functional specification is the result of analyzing class diagrams through quality attributes. In order to evaluate if the specifications are responding to communicational attributes, a functional prototype is built and evaluated with end users. The proposed methodology is applied to a real case study. 展开更多
关键词 multimedia INTERACTIVE INFORMATIVE SYSTEMS multimedia QUALITY model in Use QUALITY Requirements METAmodelING
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Multimedia Technology for Monitoring Dispatching and Production Commanding System
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作者 于洪珍 刘富强 陈力军 《International Journal of Mining Science and Technology》 SCIE EI 1998年第1期15-19,共5页
This paper describes the multimedia technology applied to the safety monitoring, management dispatching and production commanding system in the coal mine, analyzes and studies the methods of compression hased on model... This paper describes the multimedia technology applied to the safety monitoring, management dispatching and production commanding system in the coal mine, analyzes and studies the methods of compression hased on model data. In the system a multimedia computer is used to control a subsystem of safety monitoring, a subsystem of attendance management. and a subsystem of industrial TV. The multimedia computer will process the information of graphs. texts, sounds, pictures and images etc. It has the functions of real-time monitoring, emergency rescuing and accident analyzing. 展开更多
关键词 multimedia technology safety MONITORING DISPATCH model-BASED
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Nondeterministic Temporal Relations in Multimedia Data
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作者 李明禄 《High Technology Letters》 EI CAS 1996年第2期59-63,共5页
Synchronization is a important issue in multimedia systems which integrate a variety oftemporally related media objects.One part of synchronization is the representation of tempo-ral information.With the emerging inte... Synchronization is a important issue in multimedia systems which integrate a variety oftemporally related media objects.One part of synchronization is the representation of tempo-ral information.With the emerging interaetive multimedia,deterministic temporal modelsare replaced by nondeterministic ones with more expressiveness.This paper classifies tempo-ral models by their expressiveness,and evaluates the relevant nondetermi.nistic temporal re-lations in multimedia data.Additionally,an interval-based nondeterministie model based ona complete temporal operator set is proposed,providing high-level abstractions and a highdegree of expressiveness for interactive multimedia systems. 展开更多
关键词 multimedia systems SYNCHRONIZATION TEMPORAL modelS TEMPORAL RELATIONS Information REPRESENTATION
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Decomposition of Graphs Representing the Contents of Multimedia Data
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作者 Hochin Teruhisa 《通讯和计算机(中英文版)》 2010年第4期43-49,共7页
关键词 多媒体内容 分解图 数据模型 多媒体数据 递归调用 火焰传播 实例 递归图
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A Signaling Protocol Supporting Multimedia Services
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作者 李明禄 《High Technology Letters》 EI CAS 1997年第1期38-41,共4页
A flexible and extendible control mechanism for invoking services is required for taking full advantage of the potential B--ISDN services. In this paper, a flexible specification of signaling protocol based on an obje... A flexible and extendible control mechanism for invoking services is required for taking full advantage of the potential B--ISDN services. In this paper, a flexible specification of signaling protocol based on an object-oriented call mode is proposed. The article’focuses on the protocol’s message syntax, message flow model, and applicability for defining multimedia and multiparty services.’ 展开更多
关键词 B-ISDN SIGNALING protocol multimedia communications OBJECT-ORIENTED CALL model
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基于深度强化学习的计算机多媒体图像分类技术研究
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作者 陈伟 《移动信息》 2025年第4期314-316,共3页
文中深入探索了基于深度强化学习的计算机多媒体图像分类技术。首先,阐述了深度强化学习原理,包括智能体、环境、状态、动作和奖励机制,及深度神经网络在逼近价值函数或策略函数的应用。其次,介绍了多媒体图像颜色、纹理、形状特征提取... 文中深入探索了基于深度强化学习的计算机多媒体图像分类技术。首先,阐述了深度强化学习原理,包括智能体、环境、状态、动作和奖励机制,及深度神经网络在逼近价值函数或策略函数的应用。其次,介绍了多媒体图像颜色、纹理、形状特征提取方法和卷积神经网络在其中的作用。同时,详细描述了模型整体架构,含卷积神经网络感知模块和包括策略网络、价值网络的决策模块,以及奖励机制设计。最后,从训练数据集准备、训练参数设置和利用强化学习策略优化训练3个方面阐述了模型训练与优化过程,为多媒体图像分类提供了全面的技术方案。 展开更多
关键词 深度强化学习 多媒体图像 图像分类 模型构建
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A COMPUTER MULTIMEDIA BOOK OF MECHANICAL DRAWING
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作者 Zuo Zongyi Feng Kaiping 《Computer Aided Drafting,Design and Manufacturing》 1997年第1期79-86,共0页
This report gives a view of a computer multimedia book of mechanical drawing. This electronic book is developed under Windows and Chinese Star to form an integrated system on a CD-ROM. In the electronic book, graphics... This report gives a view of a computer multimedia book of mechanical drawing. This electronic book is developed under Windows and Chinese Star to form an integrated system on a CD-ROM. In the electronic book, graphics, images, 3D animation, audio, video and text techniques of computer multimedia are applied. The techniques, methods, contents and purpose of developing this system are introduced. 展开更多
关键词 multimedia mechanical drawing spiral life cycle model sound processing
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基于LLM的多媒体原生库模糊测试研究 被引量:1
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作者 解梦飞 傅建明 姚人懿 《信息网络安全》 北大核心 2025年第3期403-414,共12页
多媒体原生库通过C/C++语言直接操作底层系统资源,在显著提升音视频数据处理效率的同时,也引入了持久的内存安全威胁。然而,现有的原生库模糊测试研究不仅缺乏对多媒体库的针对性,还难以实现对闭源二进制程序的运行时监控机制。文章提... 多媒体原生库通过C/C++语言直接操作底层系统资源,在显著提升音视频数据处理效率的同时,也引入了持久的内存安全威胁。然而,现有的原生库模糊测试研究不仅缺乏对多媒体库的针对性,还难以实现对闭源二进制程序的运行时监控机制。文章提出一种基于LLM的多媒体原生库模糊测试方案MediaFuzzer,通过自启发式的LLM问询方案,MediaFuzzer能够准确提取蕴含在函数签名中的功能语义信息,并进一步筛选出潜在的多媒体原生库函数作为执行入口。随后,MediaFuzzer设计并实现了基于模拟执行的模糊测试框架,能够在系统依赖、内存管控和代码执行3个层次构建完整的运行时监控机制,从而实现覆盖率导向的输入变异以及主动捕获内存异常行为。实验结果表明,MediaFuzzer从500个移动应用中识别出7类共1557个多媒体函数,成功挖掘到WhatsApp中的1个已公开漏洞以及包括微信在内的3个零日漏洞。 展开更多
关键词 多媒体原生库 模糊测试 内存安全 大语言模型
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基于IV级逸度模型的典型抗生素多介质环境归趋研究 被引量:1
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作者 武亚林 徐井旭 +2 位作者 凌文翠 孙长虹 刘桂中 《中国环境科学》 北大核心 2025年第9期5204-5212,共9页
逸度模型是应用较为广泛的有机污染物多介质环境归趋模型,基于IV级逸度模型,本研究模拟研究了再生水补水河流凉水河中典型抗生素(氧氟沙星和罗红霉素)多介质环境归趋行为,验证了模拟可靠性,分析了平衡时迁移通量,确定了主要迁移过程,并... 逸度模型是应用较为广泛的有机污染物多介质环境归趋模型,基于IV级逸度模型,本研究模拟研究了再生水补水河流凉水河中典型抗生素(氧氟沙星和罗红霉素)多介质环境归趋行为,验证了模拟可靠性,分析了平衡时迁移通量,确定了主要迁移过程,并进行了模型关键参数灵敏度分析和不确定性分析.结果表明,模型模拟浓度与实测浓度吻合程度较高,表明模型在该研究区域的模拟有效性;研究区域内环境系统达到平衡时,水相中抗生素主要输出过程为平流过程,沉积物相主要过程是与水相的界面交换过程;平衡时氧氟沙星和罗红霉素在水和沉积物中的含量占比分别是8.73%和91.27%,27.46%和72.54%,可见沉积物是两种抗生素的主要储库;亨利定律常数H是影响两相迁移的主要因素.该研究为再生水补给型河流抗生素的环境预测与污染治理提供理论依据及决策参考. 展开更多
关键词 逸度模型 抗生素 凉水河 多介质环境归趋
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