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Annotation and Retrieval System of CAD Models Based on Functional Semantics

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1112-1124页

作者： WANG Zhansong tian ling DUAN Wenrui State Key Laboratory of Tribology & Institute of Manufacturing Engineering Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University

CAD model retrieval based on functional semantics is more significant than content-based 3D model retrieval during the mechanical conceptual design phase. However, relevant research is still not fully discussed. Therefore, a functional semantic-based CAD model annotation and retrieval method is proposed to support mechanical conceptual design and design reuse, inspire designer creativity through existing CAD models, shorten design cycle, and reduce costs. Firstly, the CAD model functional semantic ontology is constructed to formally represent the functional semantics of CAD models and describe the mechanical conceptual design space comprehensively and consistently. Secondly, an approach to represent CAD models as attributed adjacency graphs（AAG） is proposed. In this method, the geometry and topology data are extracted from STEP models. On the basis of AAG, the functional semantics of CAD models are annotated semi-automatically by matching CAD models that contain the partial features of which functional semantics have been annotated manually, thereby constructing CAD Model Repository that supports model retrieval based on functional semantics. Thirdly, a CAD model retrieval algorithm that supports multi-function extended retrieval is proposed to explore more potential creative design knowledge in the semantic level. Finally, a prototype system, called Functional Semantic-based CAD Model Annotation and Retrieval System（FSMARS）, is implemented. A case demonstrates that FSMARS can successfully botain multiple potential CAD models that conform to the desired function. The proposed research addresses actual needs and presents a new way to acquire CAD models in the mechanical conceptual design phase.

关键词： conceptual design functional semantics attributed adjacency graph CAD Model Repository multi-function extended retrieval

High Efficient Methods of Content-based 3D Model Retrieval

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 248-256页

作者： WU Yuanhao tian ling LI Chenggang Department of Precision Instruments and Mechanology Tsinghua University Baidu Online Network Technology (Beijing) Company Limited

Content-based 3D model retrieval is of great help to facilitate the reuse of existing designs and to inspire designers during conceptual design. However, there is still a gap to apply it in industry due to the low time efficiency. This paper presents two new methods with high efficiency to build a Content-based 3D model retrieval system. First, an improvement is made on the ＂Shape Distribution （D2）＂ algorithm, and a new algorithm named ＂Quick D2＂ is proposed. Four sample 3D mechanical models are used in an experiment to compare the time cost of the two algorithms. The result indicates that the time cost of Quick D2 is much lower than that of D2, while the descriptors extracted by the two algorithms are almost the same. Second, an expandable 3D model repository index method with high performance, namely, RBK index, is presented. On the basis of RBK index, the search space is pruned effectively during the search process, leading to a speed up of the whole system. The factors that influence the values of the key parameters of RBK index are discussed and an experimental method to find the optimal values of the key parameters is given. Finally, ＂3D Searcher＂, a content-based 3D model retrieval system is developed. By using the methods proposed, the time cost for the system to respond one query online is reduced by 75% on average. The system has been implemented in a manufacturing enterprise, and practical query examples during a case of the automobile rear axle design are also shown. The research method presented shows a new research perspective and can effectively improve the content-based 3D model retrieval efficiency.

关键词： 3D model retrieval high efficient methods shape descriptor extraction model repository index

Determination of Magnolol and Honokiol by Non-aqueous Capillary Electrophoresis

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Chemical Research in Chinese Universities 2006年第3期22卷 335-338页

作者： tian Yi-ling CHEN Guan-hua College of Life Science Agricultural University of Hebei Baoding 071001 P. R. China College of Food Science ＆ Technology Agricultural University of Hebei Baoding 071001 P. R. China

Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaqueous buffer on column efficiency and resolution, and the effect of acid additives on peak shapes were researched. The separation was conducted with a running buffer in a mixture of methanol/aeetonitrile/formamide （ volume ratio ： 1 ： 2 ： 2 ）, in which the concentrations of Tris, acetic acid, and water were 60 retool/L, 0. 04 mmol/L and 5% （ volume fration）, respectively, and the pH^＊（apperent pH） of the running buffer was 8.96. Magnolol and honokiol were separated on baseline within 20 min. The relative standard deviation of the analytes＇ concentrations in the sample is 1.32% for magnolol and 1.60% for honokiol, and the recoveries of the spiked sample are 98.4% for magnolol and 98. 0% for honokiol, respectively.

关键词： Nonaqueous capillary electrophoresis Magnolol Honokiol

Concurrent processes scheduling with scarce resources in small and medium enterprises

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High Technology Letters 2016年第3期22卷 273-281页

作者：马嵩华 tian ling School of Mechanical Engineering Shandong University Department of Mechanical Engineering Tsinghua University

Scarce resources,precedence and non-determined time-lag are three constraints commonly found in small and medium manufacturing enterprises(SMEs),which are deemed to block the application of workflow management system(WfMS). To tackle this problem,a workflow scheduling approach is proposed based on timing workflow net(TWF-net) and genetic algorithm(GA). The workflow is modelled in a form of TWF-net in favour of process simulation and resource conflict checking. After simplifying and reconstructing the set of workflow instance,the conflict resolution problem is transformed into a resource-constrained project scheduling problem(RCPSP),which could be efficiently solved by a heuristic method,such as GA. Finally,problems of various sizes are utilized to test the performance of the proposed algorithm and to compare it with first-come-firstserved(FCFS) strategy. The evaluation demonstrates that the proposed method is an overwhelming and effective approach for scheduling the concurrent processes with precedence and resource constraints.

关键词： concurrent processes scheduling resource constraint precedence constraint timing workflow net(TWF-net) genetic algorithm(GA)

Analyzing topics in social media for improving digital twinning based product development

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Digital Communications and Networks 2024年第2期10卷 273-281页

作者： Wenyi Tang ling tian Xu Zheng Ke Yan School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Digital twinning enables manufacturers to create digital representations of physical entities,thus implementing virtual simulations for product *** efforts of digital twinning neglect the decisive consumer feedback in product development stages,failing to cover the gap between physical and digital *** work mines real-world consumer feedbacks through social media topics,which is significant to product *** specifically analyze the prevalent time of a product topic,giving an insight into both consumer attention and the widely-discussed time of a *** primary body of current studies regards the prevalent time prediction as an accompanying task or assumes the existence of a preset ***,these proposed solutions are either biased in focused objectives and underlying patterns or weak in the capability of generalization towards diverse *** this end,this work combines deep learning and survival analysis to predict the prevalent time of *** propose a specialized deep survival model which consists of two *** first module enriches input covariates by incorporating latent features of the time-varying text,and the second module fully captures the temporal pattern of a rumor by a recurrent network ***,a specific loss function different from regular survival models is proposed to achieve a more reasonable *** experiments on real-world datasets demonstrate that our model significantly outperforms the state-of-the-art methods.

关键词： Digital twinning Product development Topic analysis Social media

Plausible Heterogeneous Graph k-Anonymization for Social Networks

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Tsinghua Science and Technology 2022年第6期27卷 912-924页

作者： Kaiyang Li ling tian Xu Zheng Bei Hui School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Trusted Cloud Computing and Big Data Key Laboratory of Sichuan Province Chengdu 610000China

The inefficient utilization of ubiquitous graph data with combinatorial structures necessitates graph embedding methods,aiming at learning a continuous vector space for the graph which is amenable to be adopted in traditional machine learning algorithms in favor of vector *** embedding methods build an important bridge between social network analysis and data analytics as social networks naturally generate an unprecedented volume of graph data *** social network data not only bring benefit for public health,disaster response,commercial promotion,and many other applications,but also give birth to threats that jeopardize each individual’s privacy and ***,most existing works in publishing social graph embedding data only focus on preserving social graph structure with less attention paid to the privacy issues inherited from social *** be specific,attackers can infer the presence of a sensitive relationship between two individuals by training a predictive model with the exposed social network *** this paper,we propose a novel link-privacy preserved graph embedding framework using adversarial learning,which can reduce adversary’s prediction accuracy on sensitive links while persevering sufficient non-sensitive information such as graph topology and node attributes in graph *** experiments are conducted to evaluate the proposed framework using ground truth social network datasets.

关键词： social network graph embedding privacy preservation adversarial learning

Optimal social welfare:A many-to-many data transaction mechanism based on double auctions

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Digital Communications and Networks 2023年第5期9卷 1230-1241页

作者： Jingyuan Duan ling tian Jianqiao Mao Jiaxin Li School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Shenzhen Institute of Information Technology China Department of Electronic and Electrical Engineering University College LondonGower StreetLondonUnited Kingdom Amazon(China)Investment Ltd China

With the development of Big Data and the Internet of Things(IoT),the data value is more significant in both academia and *** can achieve maximal data value and prepare data for smart city *** to data's unique characteristics,such as dispersion,heterogeneity and distributed storage,an unbiased platform is necessary for the data trading market with rational trading ***,there are multiple buyers and sellers in a practical data trading market,and this makes it challenging to maximize social *** solve these problems,this paper proposes a Social-Welfare-Oriented Many-to-Many Trading Mechanism(SOMTM),which integrates three entities,a trading process and an algorithm named Many-to-Many Trading Algorithm(MMTA).Based on the market scale,market dominated-side and market fixed-side,simulations verify the convergency,economic properties and efficiency of SOMTM.

关键词： Data trading Double auction Social welfare Game theory Smart city

Immunotherapy of tumor by targeting angiogenesis

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Science China(Life Sciences) 2004年第6期47卷 545-552页

作者： HOU Jianmei tian ling WEI Yuquan Key Laboratory of Biotherapy of Human Diseases of Ministry of Education West China Hospital of Sichuan universityChengdu 610041China Key Laboratory of Biotherapy of Human Diseases of Ministry of EducationWest China Hospital of Sichuan universityChengdu 610041China Key Laboratory of Biotherapy of Human Diseases of Ministry of EducationWest China Hospital of Sichuan universityChengdu 610041China

Tumor growth and metastasis are angiogenesis-dependent. Anti-angiogenic therapy represents a new strategy for the development of anti-cancer therapies. In recent years, there has been made great progress in anti-angiogenic therapy. As far as the passive immunotherapy is concerned, a recombinant humanized antibody to vascular endothelial growth factor (VEGF)— Avastin has been approved by FDA as the first angiogenesis inhibitor to treat colorectal cancer. For active specific immunotherapy, various strategies for cancer vaccines, including whole en- dothelial cell vaccines, dendritic cell vaccines, DNA vaccines, and peptides or protein vaccines, have been developed to break immune tolerance against important molecules associated with tumor angiogenesis and induce angiogenesis-specific immune responses. This article reviews the angiogenesis-targeted immunotherapy of tumor from the above two aspects.

关键词： angiogenesis, tumor, immunotherapy.

An Improved Method of Simultaneous Determination of Four Bioactive Compounds in Evodiae Fructus Using Ionic Liquids as Mobile Phase Additives in High Performance Liquid Chromatography

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Chemical Research in Chinese Universities 2017年第4期33卷 552-558页

作者： BIAN Min tian ling YAO Cheng College of Chemistry and Molecular Engineering Nanj'ing Tech University Nanjing 211800 P. R. China

There are many compounds with different structures and chemical properties in Evodiae Fructus. It is hard to simultaneously determine the bioactive compounds by high performance liquid chromatography（HPLC）. A new method was proposed for four bioactive compounds（synephrine, limonoids, evodiamine and rutecarpine） to be separated completely and determined accurately using ionic liquids（ILs） as mobile phase additives. The mechanism and the effect of the ILs for changing the chromatographic behaviors of the four compounds were studied by systemati- cally changing the pH value of mobile phase, the types and concentrations of ILs as well as the concentrations of phosphate buffer. The chromatographic behaviors of the analytes with a mobile phase containing ILs complied with the stoichiometric displacement model for retention（SDM-R）. All results demonstrate the dual nature of ionic liquids, which are competitive adsorption and ion-pair agent. Meanwhile, excellent linearity was observed for all the com- pounds with correlation coefficients between 0.9992 and 0.9998. The limit of detection and the limit of quantification of the four compounds varied from 0.47μg/mL to 0.87 μg/mL and from 1.79 μg/mL to 2.44μg/mL, respectively. Three kinds of Evodiae Fructus processed through different methods were analyzed via the method. The result shows that the contents of evodiamine and rutecarpine as the two main active compounds by processing with vinegar and salt are obviously higher than those of the raw products.

关键词： Evodiae Fructus Ionic liquid Mobile phase additive High performance liquid chromatography(HPLC) Processed Evodiae Fructus