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A new image watermarking framework based on levels-directions decomposition in contourlet representation
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作者 M.F.Kazemi M.A.Pourmina A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期521-532,共12页
With the development of digital information technologies,robust watermarking framework is taken into real consideration as a challenging issue in the area of image processing,due to the large applicabilities and its u... With the development of digital information technologies,robust watermarking framework is taken into real consideration as a challenging issue in the area of image processing,due to the large applicabilities and its utilities in a number of academic and real environments.There are a wide range of solutions to provide image watermarking frameworks,while each one of them is attempted to address an efficient and applicable idea.In reality,the traditional techniques do not have sufficient merit to realize an accurate application.Due to the fact that the main idea behind the approach is organized based on contourlet representation,the only state-of-the-art materials that are investigated along with an integration of the aforementioned contourlet representation in line with watermarking framework are concentrated to be able to propose the novel and skilled technique.In a word,the main process of the proposed robust watermarking framework is organized to deal with both new embedding and de-embedding processes in the area of contourlet transform to generate watermarked image and the corresponding extracted logo image with high accuracy.In fact,the motivation of the approach is that the suggested complexity can be of novelty,which consists of the contourlet representation,the embedding and the corresponding de-embedding modules and the performance monitoring including an analysis of the watermarked image as well as the extracted logo image.There is also a scrambling module that is working in association with levels-directions decomposition in contourlet embedding mechanism,while a decision maker system is designed to deal with the appropriate number of sub-bands to be embedded in the presence of a series of simulated attacks.The required performance is tangibly considered through an integration of the peak signal-to-noise ratio and the structural similarity indices that are related to watermarked image.And the bit error rate and the normal correlation are considered that are related to the extracted logo analysis,as well.Subsequently,the outcomes are fully analyzed to be competitive with respect to the potential techniques in the image colour models including hue or tint in terms of their shade,saturation or amount of gray and their brightness via value or luminance and also hue,saturation and intensity representations,as long as the performance of the whole of channels are concentrated to be presented.The performance monitoring outcomes indicate that the proposed framework is of significance to be verified. 展开更多
关键词 contourlet based watermarking framework levels-directions decomposition embedding process de-embedding process peak signal-to-noise ratio structural similarity indices normal correlation bit error rate
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Testability Estimation of Framework Based Applications
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作者 Noopur Goel Manjari Gupta 《Journal of Software Engineering and Applications》 2012年第11期841-849,共9页
Quality of software systems is highly demanded in today’s scenario. Highly testable system enhances the reliability also. More than 50% of test effort-time and cost are used to produce a highly testable system. Thus,... Quality of software systems is highly demanded in today’s scenario. Highly testable system enhances the reliability also. More than 50% of test effort-time and cost are used to produce a highly testable system. Thus, design-for-testability is needed to reduce the test effort. In order to enhance the quality, productivity and reduced cost of the software organizations are promoting to produce the reuse-oriented products. Incorporating reuse technology in both aspects-software development process and test process may payoff many folds. Keeping this view, our study focus the testability of the object-oriented framework based software systems and identify that flexibility at the variable points of the object-oriented framework, chosen for framework instantiation, greatly affects the testability of object-oriented framework based software at each level of testing. In the current paper, we propose a testability model considering the flexible aspect of the variable point to estimate testability in the early phase, requirement analysis phase, of development process of the framework based software. The proposed model helps to improve the testability of the software before the implementation starts thus reducing the overall development cost. 展开更多
关键词 Reuse-Technology Variation-Points OBJECT-ORIENTED framework baseD Software Basic TEST Cases framework Interface CLASSES Other Application CLASSES
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EAFoC:Enterprise Architecture Framework Based on Commonality
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作者 Jin-Woo Kim Ju-Hum Kwo +3 位作者 Young-Gab Kim Chee-Yang Song Hyun-Seok Kim Doo-Kwon Baik 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第6期952-964,共13页
The recent rapid development in information systems(ISs)has resulted in a critical need for integration and interoperability between heterogeneous ISs in various domains,using specific commonalities.However,stovepipe ... The recent rapid development in information systems(ISs)has resulted in a critical need for integration and interoperability between heterogeneous ISs in various domains,using specific commonalities.However,stovepipe systems have been caused due to inconsistencies in planning IS architecture among stakeholders.So far,there has been no research on an enterprise architecture framework(EAF)that can satisfy with the coefficient factors of system architecture(SA)and enterprise architecture(EA).This paper proposes a new EAF that can resolve the problems inherent in existing legacy EAFs and their features.EAFoC(Enterprise Architecture Framework based on Commonality)is based on commonality that can be satisfied as the coefficient factors in both SA and EA within a common information technology(IT)domain.Thus,it should be possible to integrate an established heterogeneous framework for each stakeholder's view.Consequently,the most important contribution of this paper is to establish the appropriate EAFoC for the development of consistent IS architecture,smooth communication among stakeholders,systematic integration management of diversified and complicated new IT technologies,interoperability among heterogeneous ISs,and reusability based on commonality with other platforms. 展开更多
关键词 enterprise architecture(EA) enterprise architecture framework based on commonality(EAFoC) enterprise integration(El) requirements engineering process system architecture(SA)
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Market based framework for multiple AUVs cooperation 被引量:1
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作者 YOU Guang-xin PANG Yong-jie JIANG Da-peng 《Journal of Marine Science and Application》 2005年第2期7-12,共6页
A“Market” based framework for multiple AUVs team is introduced in this paper.It is a distributed meta-level task allocation framwork. The formulation and the basic concepts of the “Market” such as “goods” and “... A“Market” based framework for multiple AUVs team is introduced in this paper.It is a distributed meta-level task allocation framwork. The formulation and the basic concepts of the “Market” such as “goods” and “price” are discussed first, then the basic algorithm of the “auction”. The loosely coupled v-MDTSP tasks are considered as an example of the task allocation mission. A multiple AUV team controller and a detailed algorithm are developed for such applications. The simulation results show that the controller has the advantages such as robustness and low complexity and it can achieve better optimization results than the classical central controller (such as GA) in some tasks. And the comparison of two different local solvers also implies that we should get the reasonable task allocation even not using the high quality algorithm, which can considerably decrease the cooperation computation. 展开更多
关键词 autonomous underwater vehicle (AUV) COOPERATION “Market” based framework
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A thiophene-containing covalent triazine-based framework with ultramicropore for CO2 capture 被引量:1
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作者 Keke Wang Yuanzhe Tang +4 位作者 Qin Jiang Youshi Lan Hongliang Huang Dahuan Liu Chongli Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第5期902-908,共7页
In this work, a 2D covalent triazine-based framework was prepared by using 1,3-dicyanobenzo[c]thiophene(DCBT) as monomer to effectively capture CO. The resulting CTF-DCBT was characterized by FT-IR, XPS, PXRD, eleme... In this work, a 2D covalent triazine-based framework was prepared by using 1,3-dicyanobenzo[c]thiophene(DCBT) as monomer to effectively capture CO. The resulting CTF-DCBT was characterized by FT-IR, XPS, PXRD, elemental analysis, SEM, TEM, and Nadsorption-desorption.The results indicate that CTF-DCBT is partially crystalline and has ultramicropore(6.5 A?) as well as high heteroatom contents(11.24 wt% and 12.61 wt% for N and S, respectively). In addition, the BET surface area and total pore volume of CTF-DCBT are 500 m/g and 0.26 cm/g, respectively. CTF-DCBT possesses excellent thermal stability(450 °C) and chemical stability towards boiling water, 4 M HCl, and 1 M Na OH.The COadsorption capacity of CTF-DCBT is 37.8 cm/g at 1 bar and 25 °C. After six adsorption-desorption cycles, there is no obvious loss of COuptake observed. Due to the ultramicropore and high heteroatom contents, CTF-DCBT has high isosteric heats of adsorption for COand high selectivities of COover Nand CH. At 25 °C, the CO/Nand CO/CHselectivities are 112.5 and 10.3, respectively, which are higher than those of most POFs. Breakthrough curves indicate that CTF-DCBT could effectively separate CO/Nand CO/CHmixtures. 展开更多
关键词 Covalent triazine-based framework Ultramicropore Adsorption Carbon dioxide
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Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries 被引量:7
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作者 Qingping Wu Xuejun Zhou +2 位作者 Jun Xu Fahai Cao Chilin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期94-113,共20页
Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh... Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed. 展开更多
关键词 Lithium-sulfur BATTERIES Carbon-based DERIVATIVES Metal-organic frame works CATHODE host
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A Study on the Explainability of Thyroid Cancer Prediction:SHAP Values and Association-Rule Based Feature Integration Framework
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作者 Sujithra Sankar S.Sathyalakshmi 《Computers, Materials & Continua》 SCIE EI 2024年第5期3111-3138,共28页
In the era of advanced machine learning techniques,the development of accurate predictive models for complex medical conditions,such as thyroid cancer,has shown remarkable progress.Accurate predictivemodels for thyroi... In the era of advanced machine learning techniques,the development of accurate predictive models for complex medical conditions,such as thyroid cancer,has shown remarkable progress.Accurate predictivemodels for thyroid cancer enhance early detection,improve resource allocation,and reduce overtreatment.However,the widespread adoption of these models in clinical practice demands predictive performance along with interpretability and transparency.This paper proposes a novel association-rule based feature-integratedmachine learning model which shows better classification and prediction accuracy than present state-of-the-artmodels.Our study also focuses on the application of SHapley Additive exPlanations(SHAP)values as a powerful tool for explaining thyroid cancer prediction models.In the proposed method,the association-rule based feature integration framework identifies frequently occurring attribute combinations in the dataset.The original dataset is used in trainingmachine learning models,and further used in generating SHAP values fromthesemodels.In the next phase,the dataset is integrated with the dominant feature sets identified through association-rule based analysis.This new integrated dataset is used in re-training the machine learning models.The new SHAP values generated from these models help in validating the contributions of feature sets in predicting malignancy.The conventional machine learning models lack interpretability,which can hinder their integration into clinical decision-making systems.In this study,the SHAP values are introduced along with association-rule based feature integration as a comprehensive framework for understanding the contributions of feature sets inmodelling the predictions.The study discusses the importance of reliable predictive models for early diagnosis of thyroid cancer,and a validation framework of explainability.The proposed model shows an accuracy of 93.48%.Performance metrics such as precision,recall,F1-score,and the area under the receiver operating characteristic(AUROC)are also higher than the baseline models.The results of the proposed model help us identify the dominant feature sets that impact thyroid cancer classification and prediction.The features{calcification}and{shape}consistently emerged as the top-ranked features associated with thyroid malignancy,in both association-rule based interestingnessmetric values and SHAPmethods.The paper highlights the potential of the rule-based integrated models with SHAP in bridging the gap between the machine learning predictions and the interpretability of this prediction which is required for real-world medical applications. 展开更多
关键词 Explainable AI machine learning clinical decision support systems thyroid cancer association-rule based framework SHAP values classification and prediction
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Retinex based low-light image enhancement using guided filtering and variational framework 被引量:6
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作者 张诗 唐贵进 +2 位作者 刘小花 罗苏淮 王大东 《Optoelectronics Letters》 EI 2018年第2期156-160,共5页
A new image enhancement algorithm based on Retinex theory is proposed to solve the problem of bad visual effect of an image in low-light conditions. First, an image is converted from the RGB color space to the HSV col... A new image enhancement algorithm based on Retinex theory is proposed to solve the problem of bad visual effect of an image in low-light conditions. First, an image is converted from the RGB color space to the HSV color space to get the V channel. Next, the illuminations are respectively estimated by the guided filtering and the variational framework on the V channel and combined into a new illumination by average gradient. The new reflectance is calculated using V channel and the new illumination. Then a new V channel obtained by multiplying the new illumination and reflectance is processed with contrast limited adaptive histogram equalization(CLAHE). Finally, the new image in HSV space is converted back to RGB space to obtain the enhanced image. Experimental results show that the proposed method has better subjective quality and objective quality than existing methods. 展开更多
关键词 RGB CLAHE Retinex based low-light image enhancement using guided filtering and variational framework HSV
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Agent-based model of land system:Theory,application and modelling framework 被引量:2
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作者 DAI Erfu MA Liang +3 位作者 YANG Weishi WANG Yahui YIN Le TONG Miao 《Journal of Geographical Sciences》 SCIE CSCD 2020年第10期1555-1570,共16页
Land change science has become an interdisciplinary research direction for understanding human-natural coupling systems.As a process-oriented modelling approach,agent based model(ABM)plays an important role in reveali... Land change science has become an interdisciplinary research direction for understanding human-natural coupling systems.As a process-oriented modelling approach,agent based model(ABM)plays an important role in revealing the driving forces of land change and understanding the process of land change.This paper starts from three aspects:The theory,application and modeling framework of ABM.First,we summarize the theoretical basis of ABM and introduce some related concepts.Then we expound the application and development of ABM in both urban land systems and agricultural land systems,and further introduce the case study of a model on Grain for Green Program in Hengduan Mountainous region,China.On the basis of combing the ABM modeling protocol,we propose the land system ABM modeling framework and process from the perspective of agents.In terms of urban land use,ABM research initially focused on the study of urban expansion based on landscape,then expanded to issues like urban residential separation,planning and zoning,ecological functions,etc.In terms of agricultural land use,ABM application presents more diverse and individualized features.Research topics include farmers’behavior,farmers’decision-making,planting systems,agricultural policy,etc.Compared to traditional models,ABM is more complex and difficult to generalize beyond specific context since it relies on local knowledge and data.However,due to its unique bottom-up model structure,ABM has an indispensable role in exploring the driving forces of land change and also the impact of human behavior on the environment. 展开更多
关键词 land system land use land change science land change model agent-based model modeling framework
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Synthesis, Structure and Electrocatalytic Activity of Perfluorinated Covalent Triazine-based Framework
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作者 WANG Yuan-Shuang WEN Zhen-Hai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第2期233-241,166,共10页
Using the bottom-up method, we synthesized a series of perfluorinated covalent triazine-based frameworks(FCTFs) with porous structures for catalysis oxygen reduction reaction(ORR). The evolved FCTFs by high-temperatur... Using the bottom-up method, we synthesized a series of perfluorinated covalent triazine-based frameworks(FCTFs) with porous structures for catalysis oxygen reduction reaction(ORR). The evolved FCTFs by high-temperature carbonization show an apparent variation in electrocatalytic activity toward the ORR dependent on the type of F. The samples synthesized at 900 ℃(FCTF-900) exhibits advantages in terms of high activity, high durability, and methanol-tolerant as an efficient electrocatalyst for ORR, manifests a comparable or even better activity as compared with the commercial Pt/C catalysts not only in alkaline media but also in acidic and neutral electrolyte. 展开更多
关键词 electrochemical reduction porous polymers COVALENT triazine-based framework ionothermal polymerization
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A Conceptual and Computational Framework for Aspect-Based Collaborative Filtering Recommender Systems 被引量:1
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作者 Samin Poudel Marwan Bikdash 《Journal of Computer and Communications》 2023年第3期110-130,共21页
Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspe... Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspects of the items thus leading to more sophisticated and justifiable recommendations. However, most Collaborative Filtering (CF) techniques rely mainly on the overall preferences of users toward items only. And there is lack of conceptual and computational framework that enables an understandable aspect-based AI approach to recommending items to users. In this paper, we propose concepts and computational tools that can sharpen the logic of recommendations and that rely on users’ sentiments along various aspects of items. These concepts include: The sentiment of a user towards a specific aspect of a specific item, the emphasis that a given user places on a specific aspect in general, the popularity and controversy of an aspect among groups of users, clusters of users emphasizing a given aspect, clusters of items that are popular among a group of users and so forth. The framework introduced in this study is developed in terms of user emphasis, aspect popularity, aspect controversy, and users and items similarity. Towards this end, we introduce the Aspect-Based Collaborative Filtering Toolbox (ABCFT), where the tools are all developed based on the three-index sentiment tensor with the indices being the user, item, and aspect. The toolbox computes solutions to the questions alluded to above. We illustrate the methodology using a hotel review dataset having around 6000 users, 400 hotels and 6 aspects. 展开更多
关键词 Recommender System Collaborative Filtering Aspect based recommendation Recommendation System framework Aspect Sentiments
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Using a Task-based Teaching Framework in Lesson Designing
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作者 王锦霞 《山东师范大学外国语学院学报(基础英语教育)》 2005年第4期61-65,共5页
Task-basedteachingandlearningis becoming more and more popularin China now,andthe aimof taskis to create a real purpose for language use and provide a natural context for language study· This article introduces w... Task-basedteachingandlearningis becoming more and more popularin China now,andthe aimof taskis to create a real purpose for language use and provide a natural context for language study· This article introduces what a task-based teaching frameworkis and the three phases of pre-task, while-task and post-task,combined withsomethoughts about howwe shouldconvertthosetasksinto actual classroomactivities while using the task-based teaching framework in designing the lessons and howthe teacher and students participate inthe lessons· 展开更多
关键词 任务驱动式教学 英语教学 教学设计 中学 教学方法
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基于慢性病轨迹框架的帕金森病中西医结合健康教育方案的构建
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作者 金婕 龙秀红 +6 位作者 文晓东 杨甜甜 范葵钰 周晓燕 梁珊珊 魏金金 林思慧 《护理研究》 北大核心 2026年第4期573-583,共11页
目的:构建基于慢性病轨迹框架的帕金森病中西医结合健康教育方案,为临床护士提供循证依据。方法:以慢性病轨迹框架为指导,基于循证研究形成方案初稿,采用德尔菲法确定最终方案。选择三级甲等医院192名神经内科护士进行方案可行性测评。... 目的:构建基于慢性病轨迹框架的帕金森病中西医结合健康教育方案,为临床护士提供循证依据。方法:以慢性病轨迹框架为指导,基于循证研究形成方案初稿,采用德尔菲法确定最终方案。选择三级甲等医院192名神经内科护士进行方案可行性测评。结果:共进行了2轮专家函询。专家权威系数分别为0.815和0.855,变异系数均<0.25,肯德尔和谐系数分别为0.420和0.481(均P<0.01)。最终形成涵盖病前、始发、确诊、治疗、稳定、恶化、临终7个疾病轨迹阶段的帕金森病中西医结合健康教育方案。方案可行性测评显示方案结构合理性、内容科学性、实施可行性、整体评价4个维度均分均>4.5分。结论:构建的帕金森病中西医结合健康教育方案具有科学性、可靠性与可行性,可为帕金森病全程健康管理提供标准化工具,为临床护士开展帕金森病健康教育工作提供循证依据。 展开更多
关键词 帕金森病 慢性病轨迹框架 健康教育 循证护理
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Two Generic Frameworks of Multiple Viewpoints Oriented Requirements Method and Their Comparison
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作者 Song Qiang, He Yan xiang, Huang Qian School of Computer Science, State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期313-319,共7页
Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develo... Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develops two generic formal frameworks of MVORM, framework based on refinement relation (FBRR) and framework based on implementation relation (FBIR). They are generic, because no assumptions are made about the development process or the formal description languages to be used. Three kinds of specification relations and three kinds of specification transformations are discussed over FBIR and FBRR. This paper also compares the equivalence between FBIR and FBRR. We point out that an equivalent FBIR can be found for any FBRR, but reverse transformation is not always possible. We think FBIR is better than FBRR on most cases. 展开更多
关键词 multiple viewpoints oriented requirements method framework based on refinement relation framework based on implementation relation refinement relation implementation relation
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Optimization of RDF link traversal based query execution 被引量:2
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作者 朱艳琴 花岭 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期27-32,共6页
Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal ba... Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal based query execution (RDF-LTE) approach, this paper discusses how the execution order of the triple pattern affects the query results and cost based on concrete SPARQL queries, and analyzes two properties of the web of linked data, missing backward links and missing contingency solution. Then three heuristic principles for logic query plan optimization, namely, the filtered basic graph pattern (FBGP) principle, the triple pattern chain principle and the seed URIs principle, are proposed. The three principles contribute to decrease the intermediate solutions and increase the types of queries that can be answered. The effectiveness and feasibility of the proposed approach is evaluated. The experimental results show that more query results can be returned with less cost, thus enabling users to develop the full potential of the web of linked data. 展开更多
关键词 web of linked data resource description framework link traversal based query execution (RDF-LTE) SPARQL query query optimization
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卟啉基共价有机骨架/茄尼醇复合材料用于协同杀菌
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作者 许恒誉 蒋志才 +8 位作者 刘博 蔡兴华 林建南 乔跃辉 陈昭定 覃雪冰 吴金格 王永熙 郭敬轩 《分析测试学报》 北大核心 2026年第1期135-142,共8页
该文以光敏剂(TAPP)和乙烯基单体为功能单元,制备了卟啉基COF(TB),进一步负载天然抗菌物质茄尼醇(Sol),构建了集光动力/光热/化学杀菌于一体的新型复合材料(TB-Sol)。TB多孔结构对Sol吸附容量达207.8 mg·g^(-1),其高度有序的结构... 该文以光敏剂(TAPP)和乙烯基单体为功能单元,制备了卟啉基COF(TB),进一步负载天然抗菌物质茄尼醇(Sol),构建了集光动力/光热/化学杀菌于一体的新型复合材料(TB-Sol)。TB多孔结构对Sol吸附容量达207.8 mg·g^(-1),其高度有序的结构确保了TAPP单元呈现出良好的产单线态氧和光热升温能力(TB的光动力性能为游离TAPP的191.51%)。Sol的引入进一步提升了TB-Sol的抗菌活性,在100 mW·cm^(-2)的白光LED照射30 min后,TB-Sol(233μg·mL^(-1))对大肠杆菌(E. coli)和金黄色葡萄球菌(S. aureus)的杀菌率分别达99.46%和97.34%,远高于同等浓度的TB(82.62%和66.14%)。 展开更多
关键词 卟啉共价有机骨架 茄尼醇 光疗 细菌感染 协同杀菌
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以支出审查为基础的英国零基预算制度演进与启示
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作者 曹堂哲 王梦琦 吕阳 《财政科学》 2026年第1期44-57,共14页
在各国零基预算模式中,英国以支出审查制度为核心构建零基预算体系。该制度始于20世纪90年代,通过“综合支出审查”“一般性支出审查”等制度体系,实现了财政政策确定、总量控制、资源配置与运营效率提升。其实施机制涵盖部门编制、财... 在各国零基预算模式中,英国以支出审查制度为核心构建零基预算体系。该制度始于20世纪90年代,通过“综合支出审查”“一般性支出审查”等制度体系,实现了财政政策确定、总量控制、资源配置与运营效率提升。其实施机制涵盖部门编制、财政部审核及跨部门协商等关键环节,将公共服务协议、单部门计划等绩效管理形式融入预算管理全过程。2025年英国的支出审查实施了全部门零基审查、数字赋能、跨期平衡等创新举措,强化战略优先级协同与数据驱动决策。英国经验表明,零基预算需通过支出审查等常态化制度整合宏观财政政策、预算安排和绩效管理,提升财政治理和政府治理效能。对我国而言,“十五五”时期预算与绩效管理改革应强化零基预算绩效管理的系统集成性、建立自上而下的零基预算管理体系、完善零基预算管理中“花钱”和“办事”的关系、完善成本效益分析和公平评估制度、更注重跨部门预算和绩效管理问题。 展开更多
关键词 零基预算 支出审查 中期预算框架 成本效益分析 预算绩效管理
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6061铝合金阳极氧化-电沉积制备Ce-MOF@TA复合膜层及其耐蚀性
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作者 刘涵钰 张宇 +4 位作者 赵蕊 岳浩 尚伟 张哲 温玉清 《电镀与涂饰》 北大核心 2026年第1期86-93,共8页
[目的]6061铝合金在长期使用中易发生腐蚀失效。为提高其使用寿命,需开发结合力强、防护性能持久的表面防护膜层。[方法]先对6061铝合金进行阳极氧化,得到多孔阳极氧化(PAO)底层,再通过电沉积法制备了负载单宁酸(TA)缓蚀剂的铈基金属有... [目的]6061铝合金在长期使用中易发生腐蚀失效。为提高其使用寿命,需开发结合力强、防护性能持久的表面防护膜层。[方法]先对6061铝合金进行阳极氧化,得到多孔阳极氧化(PAO)底层,再通过电沉积法制备了负载单宁酸(TA)缓蚀剂的铈基金属有机框架(Ce-MOF@TA)复合膜层。研究了电沉积时间、电压、1,3,5-苯三甲酸(H_(3)BTC)配体与金属盐物质的量比及TA质量浓度对膜层耐蚀性的影响。[结果]电沉积Ce-MOF@TA复合膜层的较优工艺参数为:H_(3)BTC与Ce(NO_(3))_(3)·6H_(2)O物质的量比1∶1,TA质量浓度7.5 g/L,电压15 V,时间40 min。在该条件下制备的Ce-MOF@TA膜层的腐蚀电流密度低至1.905×10^(-8) A/cm^(2),电荷转移电阻高达1.359×10^(7)Ω·cm^(2),经144 h中性盐雾试验后表面完好,未见点蚀。[结论]通过阳极氧化与电沉积相结合,在6061铝合金表面成功制备了Ce-MOF@TA复合膜层。该膜层结构致密,与基体结合良好,且TA缓蚀剂的引入与MOF结构产生了协同防护效应,使膜层具备优异的耐腐蚀性能,能有效延长铝合金在腐蚀环境中的服役寿命。 展开更多
关键词 铝合金 阳极氧化 电沉积 铈基金属有机框架 缓蚀剂 耐蚀性
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基于故事情境的教师智能素养测评:理论耦合、操作框架与实践进路 被引量:1
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作者 李世瑾 顾小清 《电化教育研究》 北大核心 2026年第2期104-112,共9页
生成式人工智能时代对教师素养发展提出了新要求,科学测评是系统提升教师智能素养的关键前提。为有效评估教师智能素养发展水平,本研究引入故事情境任务设计范式,系统阐释其测评内涵与逻辑关联,构建相应操作框架,并从任务主题选取、任... 生成式人工智能时代对教师素养发展提出了新要求,科学测评是系统提升教师智能素养的关键前提。为有效评估教师智能素养发展水平,本研究引入故事情境任务设计范式,系统阐释其测评内涵与逻辑关联,构建相应操作框架,并从任务主题选取、任务架构设计、任务内容开发及评价量尺制定等方面细化实施步骤。研究发现,该范式通过设计以智能技术应用为核心的连贯情境任务,能够将智能素养指标嵌入故事线中,并基于教师在任务过程中的行为选择与决策表现,实现对其智能素养发展水平的动态映射与客观评估。研究表明,故事情境任务测评方法兼具指标系统性与数据真实性优势,为教师智能素养测评提供了新路径。未来应进一步强化任务设计效度、提升实践效率、拓展应用广度,以推动构建循证导向的教师智能素养测评体系。 展开更多
关键词 教师智能素养 故事情境 测评方法 操作框架 教师发展
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一种隐式稳定节点光滑有限元分解ALE法及其在大变形分析中的应用
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作者 陈曦 吕彦楠 +3 位作者 于玉贞 崔柳生 许哲 郭菁 《岩土工程学报》 北大核心 2026年第2期250-258,共9页
岩土工程常涉及土体大变形问题,采用基于小变形假设的有限元法对其进行分析会产生较大计算误差或因网格畸变而导致计算中断。分解任意拉格朗日-欧拉(ALE)法将网格变形与材料变形分离,分别执行更新拉格朗日(UL)步与欧拉步以便克服网格畸... 岩土工程常涉及土体大变形问题,采用基于小变形假设的有限元法对其进行分析会产生较大计算误差或因网格畸变而导致计算中断。分解任意拉格朗日-欧拉(ALE)法将网格变形与材料变形分离,分别执行更新拉格朗日(UL)步与欧拉步以便克服网格畸变引起的计算精度降低或计算中断问题。将稳定节点光滑有限元(NsFEMstab)法与ALE法相结合,提出一种新的NsFEMstab-ALE法,并提出一种用于网格自适应调整策略的动态布点法。以刚性基础地基大变形问题为例,对NsFEMstab-ALE进行检验,数值结果表明:①基于网格自适应调整策略的动态布点法能够有效解决大变形引起的网格畸变问题,实现网格疏密平滑过渡,确保大变形模拟过程中整个网格单元具有良好质量;②应用NsFEMstab-ALE法时,能够获得与参考文献相符的荷载-位移响应曲线以及合理的等效塑性应变云图和网格变形图。 展开更多
关键词 土体大变形 稳定节点光滑有限元法 隐式有限元框架 自适应网格重划分 任意拉格朗日-欧拉法
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