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Modulating Ligand-Exchange Dynamics on Metal-Organic Polyhedra for Reversible Sorting and Hybridization of Miktoarm Star Polymers

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Angewandte Chemie 2023年第49期135卷

作者： Yuyan Lai Xiaofeng He Binghui Xue Mu Li Dr. Huihui Wang Dr. Wei Huang Dr. Jia-Fu Yin Dr. Mingxin Zhang Prof. Dr. Panchao Yin State Key Laboratory of Luminescent Materials and Devices South China Advanced Institute for Soft Matter Science and Technology South China University of Technology Guangzhou 510640 P. R. China Contribution: Investigation (lead) Methodology (equal) Writing - original draft (equal) Contribution: Investigation (equal) Methodology (supporting) Writing - original draft (equal) Contribution: Data curation (equal) Methodology (supporting) Validation (supporting) Contribution: Formal analysis (equal) Resources (supporting) Validation (supporting) State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine Chemistry School of Chemical Engineering and Technology Hainan University Haikou Hainan 570228 P. R. China Contribution: Methodology (supporting) Validation (supporting) Contribution: Formal analysis (supporting) Validation (supporting) Contribution: Formal analysis (supporting) Visualization (supporting) Contribution: Conceptualization (equal) Formal analysis (equal) Investigation (equal) Supervision (supporting) Visualization (lead) Writing - original draft (equal) Contribution: Conceptualization (lead) Formal analysis (equal) Funding acquisition (lead) Project administration (lead) Supervision (lead) Validation (equal) Writing - original draft (equal) Writing - review & editing (lead)

The precise synthesis of miktoarm star polymers (MSPs) remains one of the great challenges in synthetic chemistry due to the difficulty in locating appropriate structural templates and polymer grafting/growing strategies with high selectivity and efficiency. Herein, ≈2 nm metal-organic polyhedra (MOPs), constructed from the coordination of isophthalic acid (IPA) and Cu 2+ , are applied as templates for the precise synthesis of 24-arm MSPs for their unique logarithmic ligand-exchange dynamics. Six different polymers are prepared with IPA as an end group and they further coordinated with Cu 2+ to afford the corresponding 24-arm star homo-polymers. MSPs can be obtained by mixing targeted homo-arm star polymers in solutions upon thermal annealing. The compositions of MSPs can be facilely and precisely tuned by the recipe of the star polymer mixtures used. Interestingly, the obtained MSPs can be sorted into homo-arm star polymers through a typical solvent extraction procedure. The hybridization and sorting process can be reversibly conducted through the cycle of thermal annealing and solvent treatment. The complex coordination framework not only opens new avenues for the facile and precise synthesis of MSPs and MOPs with hybrid functionalities, but also provides the capability to design sustainable polymer systems.

关键词： Inorganic–Organic Hybrid Materials Metal–Organic Polyhedra Miktoarm Star Polymers Solution Dynamics Sustainable Polymers

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Question-answering aspect classification with hierarchical attention network 17th

Question-answering aspect classification with hierarchical a...

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17th China National Conference on Computational Linguistics, CCL 2018 and 6th International Symposium on Natural Language Processing Based on Naturally Annotated Big data, NLP-NABD 2018

作者： Wu, Hanqian Liu, Mumu Wang, Jingjing Xie, Jue Shen, Chenlin School of Computer Science and Engineering Southeast University Nanjing China Key Laboratory of Computer Network and Information Integration of Ministry of Education Southeast University Nanjing China NLP Lab School of Computer Science and Technology Soochow University Suzhou China Southeast University-Monash University Joint Graduate School Suzhou China

ISBN: (纸本)9783030017156

In e-commerce websites, user-generated question-answering text pairs generally contain rich aspect information of products. In this paper, we address a new task, namely Question-answering (QA) aspect classification, which aims to automatically classify the aspect category of a given QA text pair. In particular, we build a high-quality annotated corpus with specifically designed annotation guidelines for QA aspect classification. On this basis, we propose a hierarchical attention network to address the specific challenges in this new task in three stages. Specifically, we firstly segment both question text and answer text into sentences, and then construct (sentence, sentence) units for each QA text pair. Second, we leverage a QA matching attention layer to encode these (sentence, sentence) units in order to capture the aspect matching information between the sentence inside question text and the sentence inside answer text. Finally, we leverage a self-matching attention layer to capture different importance degrees of different (sentence, sentence) units in each QA text pair. Experimental results demonstrate that our proposed hierarchical attention network outperforms some strong baselines for QA aspect classification. © Springer Nature Switzerland AG 2018.

关键词： Text processing

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A Performance Comparison Study of Parallel Clustering Algorithms in Cluster Environments 2

A Performance Comparison Study of Parallel Clustering Algori...

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2017 IEEE 2nd International Conference on Big data Analysis（ICBDA 2017）

作者： Mo Hai School of Information Central University of Finance and Economics Network and Data Security Key Laboratory of Sichuan Province University of Electronic Science and Technology of China

ISBN: (纸本)9781509036202

We compare the performance of three parallel clustering algorithms:Canopy,K-means and fuzzy K-means in real cluster *** constructing cluster platform of different scale,we compare these algorithms from three metrics:run time,speedup and *** results show that:(1) if both the data set and the number of nodes in the cluster are the same,both the runtime and the sizeup of Canopy is the smallest,and the speedup of Canopy is the largest among these three algorithms;(2) when the number of nodes is larger than 2,for each algorithm,the difference between the sizeup on different data set becomes more and more smaller as the number of nodes increases;at the same time,when the number of nodes is larger than 2 and the data set is the same,the sizeup of Canopy has the maximum decrease with the increase of the number of nodes;(3) when the number of nodes keeps the same,the difference between the sizeup of these three algorithms becomes more and more apparent as the size of the data set increases.

关键词： Canopy K-means Fuzzy K-means Cluster platform Run time Speedup Sizeup

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Τ-FPL: Tolerance-constrained learning in linear time 32

Τ-FPL: Tolerance-constrained learning in linear time

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32nd AAAI Conference on Artificial Intelligence, AAAI 2018

作者： Zhang, Ao Li, Nan Pu, Jian Wang, Jun Yan, Junchi Zha, Hongyuan Shanghai Key Laboratory of Trustworthy Computing MOE International Joint Lab of Trustworthy Software School of Computer Science and Software Engineering East China Normal University Shanghai China Institute of Data Science and Technologies Alibaba Group Hangzhou China IBM Research China Georgia Institute of Technology Atlante United States

ISBN: (纸本)9781577358008

In many real-world applications, learning a classifier with false-positive rate under a specified tolerance is appealing. Existing approaches either introduce prior knowledge dependent label cost or tune parameters based on traditional classifiers, which are of limitation in methodology since they do not directly incorporate the false-positive rate tolerance. In this paper, we propose a novel scoring-thresholding approach, τ-False Positive Learning (τ-FPL) to address this problem. We show that the scoring problem which takes the false-positive rate tolerance into accounts can be efficiently solved in linear time, also an out-of-bootstrap thresholding method can transform the learned ranking function into a low false-positive classifier. Both theoretical analysis and experimental results show superior performance of the proposed τ-FPL over the existing approaches. Copyright © 2018, Association for the Advancement of Artificial Intelligence (***). All rights reserved.

关键词： Mathematical transformations

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Joint Ranking SVM and Binary Relevance with Robust Low-Rank Learning for Multi-label Classification

arXiv

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arXiv 2019年

作者： Wu, Guoqiang Zheng, Ruobing Tian, Yingjie Liu, Dalian School of Computer Science and Technology University of Chinese Academy of Sciences Beijing100049 China Research Center on Fictitious Economy and Data Science Chinese Academy of Sciences Beijing100190 China Computer Network Information Center Chinese Academy of Sciences Beijing100190 China School of Economics and Management University of Chinese Academy of Sciences Beijing100190 China Key Laboratory of Big Data Mining and Knowledge management Chinese Academy of Sciences Beijing100190 China Department of Basic Course Teaching Beijing Union University Beijing100101 China

Multi-label classification studies the task where each example belongs to multiple labels simultaneously. As a representative method, Ranking Support Vector Machine (Rank-SVM) aims to minimize the Ranking Loss and can also mitigate the negative influence of the class-imbalance issue. However, due to its stacking-style way for thresholding, it may suffer error accumulation and thus reduces the final classification performance. Binary Relevance (BR) is another typical method, which aims to minimize the Hamming Loss and only needs one-step learning. Nevertheless, it might have the class-imbalance issue and doesn’t take into account label correlations. To address the above issues, we propose a novel multi-label classification model, which joints Ranking support vector machineNovember 6, 2019 and Binary Relevance with robust Low-rank learning (RBRL). RBRL inherits the ranking loss minimization advantages of Rank-SVM, and thus overcomes the disadvantages of BR suffering the class-imbalance issue and ignoring the label correlations. Meanwhile, it utilizes the hamming loss minimization and one-step learning advantages of BR, and thus tackles the disadvantages of Rank-SVM including another thresholding learning step. Besides, a low-rank constraint is utilized to further exploit high-order label correlations under the assumption of low dimensional label space. Furthermore, to achieve nonlinear multi-label classifiers, we derive the kernelization RBRL. Two accelerated proximal gradient methods (APG) are used to solve the optimization problems efficiently. Extensive comparative experiments with several state-of-the-art methods illustrate a highly competitive or superior performance of our method RBRL. Copyright © 2019, The Authors. All rights reserved.

关键词： Classification (of information)

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Bicycle flow dynamics on wide roads: Experiment and modeling

arXiv

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arXiv 2019年

作者： Guo, Ning Jiang, Rui Wong, S.C. Hao, Qing-Yi Xue, Shu-Qi Hu, Mao-Bin School of Automotive and Transportation Engineering Hefei University of Technology Hefei230009 China Key Lab. of Transport Industry of Big Data Application Technologies for Comprehensive Transport Ministry of Transport Beijing Jiaotong University Beijing100044 China Department of Civil Engineering University of Hong Kong Pokfulam Road Hong Kong School of Mathematics and Computational Science Anqing Normal University Anqing246133 China School of Engineering Science University of Science and Technology of China Hefei230026 China

Cycling is a green transportation mode, and is promoted by many governments to mitigate traffic congestion. However, studies concerning the traffic dynamics of bicycle flow are very limited. This study experimentally investigated bicycle flow dynamics on a wide road, modeled using a 3-m-wide track. The results showed that the bicycle flow rate remained nearly constant across a wide range of densities, in marked contrast to single-file bicycle flow, which exhibits a unimodal fundamental diagram. By studying the weight density of the radial locations of cyclists, we argue that this behavior arises from the formation of more lanes with the increase of global density. The extra lanes prevent the longitudinal density from increasing as quickly as in single-file bicycle flow. When the density is larger than 0.5 bicycles/m2, the flow rate begins to decrease, and stop-and-go traffic emerges. A cognitive-science-based model to reproduce bicycle dynamics is proposed, in which cyclists apply simple cognitive procedures to adapt their target directions and desired riding speeds. To incorporate differences in acceleration, deceleration, and turning, different relaxation times are used. The model can reproduce the experimental results acceptably well and may also provide guidance on infrastructure design. Copyright © 2019, The Authors. All rights reserved.

关键词： Traffic congestion

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Optimal algorithm for profiling dynamic arrays with finite values

arXiv

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arXiv 2018年

作者： Yang, Dingcheng Yu, Wenjian Deng, Junhui Liu, Shenghua BNRist Dept. Computer Science & Tech. Tsinghua Univ. Beijing China CAS Key Lab. Network Data Science & Tech. Inst. Computing Technology Chinese Academy of Sciences Beijing China

How can one quickly answer the most and top popular objects at any time, given a large log stream in a system of billions of users? It is equivalent to find the mode and top-frequent elements in a dynamic array corresponding to the log stream. However, most existing work either restrain the dynamic array within a sliding window, or do not take advantages of only one element can be added or removed in a log stream. Therefore, we propose a profiling algorithm, named S-Profile, which is of O(1) time complexity for every updating of the dynamic array, and optimal in terms of computational complexity. With the profiling results, answering the queries on the statistics of dynamic array becomes trivial and fast. With the experiments of various settings of dynamic arrays, our accurate S-Profile algorithm outperforms the well-known methods, showing at least 2X speedup to the heap based approach and 13X or larger speedup to the balanced tree based approach. Copyright © 2018, The Authors. All rights reserved.

关键词： Computational complexity

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Circularly and Linearly Polarized Luminescence from AIE Luminogens Induced by Super-Aligned Assemblies of Sub-1 nm Nanowires

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Angewandte Chemie 2022年第34期134卷

作者： Shujian Rong Prof. Wenxiong Shi Dr. Simin Zhang Prof. Dr. Xun Wang Key Lab of Organic Optoelectronics and Molecular Engineering Department of Chemistry Tsinghua University Beijing 100084 China Contribution: Investigation (lead) Methodology (lead) Writing - original draft (lead) Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology Tianjin 300387 China Contribution: Data curation (lead) Formal analysis (lead) Software (lead) Contribution: Conceptualization (equal) Formal analysis (lead) Methodology (lead) Writing - review & editing (equal) Contribution: Conceptualization (lead) Data curation (lead) Formal analysis (lead) Funding acquisition (lead) Investigation (lead) Methodology (lead) Project administration (lead) Resources (lead) Supervision (lead) Validation (lead) Writing - review & editing (lead)

Sub-1 nm nanowires (SNWs) combine the properties of inorganic materials and polymers. They can be highly oriented through assembly, and can also be easily processed. Meanwhile, aggregation-induced emission luminogens (AIEgens) show high potential for optical applications, but they are usually hard to process. The combination of SNWs and AIEgens can enrich both of their applications. In this study, we report that the fluorescence emission intensity of the AIEgens–SNW dispersion is dramatically enhanced due to the flexibility of SNWs. Furthermore, we fabricate two kinds of functional films with circularly polarized luminescence (CPL) and linearly polarized luminescence (LPL) activities. The construction of CPL materials didn't require any chiral chemicals. The construction of LPL materials didn't require an additional stretching process. As a result, we endowed common achiral AIEgens with a high dissymmetry factor of 0.033 and a polarization ratio of 0.44, respectively.

关键词： Aggregation-Induced Emission (AIE) Circularly Polarized Luminescence Linearly Polarized Luminescence Self-Assembly Sub-1 nm Nanowires

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Corrigendum to “3D shape segmentation via shape fully convolutional networks” [Computers & Graphics 70 (2018) 128–139]

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Computers and Graphics (Pergamon) 2018年 76卷 181-181页

作者： Wang, Pengyu Gan, Yuan Shui, Panpan Yu, Fenggen Zhang, Yan Chen, Songle Sun, Zhengxing State Key Lab for Novel Software Technology Department of Computer Science and Technology Nanjing University Nanjing210023 China Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education College of Internet of Things Nanjing University of Posts and Telecommunications Nanjing210003 China

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56-Gb/s optical SSB PAM-4 transmission over 800-km SSMF using DDMZM transmitter and simplified direct detection Kramers-Kronig receiver

56-Gb/s optical SSB PAM-4 transmission over 800-km SSMF usin...

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Optical Fiber Communication Conference, OFC 2018

作者： Zhu, Mingyue Zhang, Jing Ying, Hao Li, Xiang Luo, Ming Huang, Xiatao Song, Yingxiong Li, Fan Yi, Xingwen Qiu, Kun Key Lab. of Optical Fiber Sensing and Communications University of Electronic Science and Technology of China Chengdu611731 China State Key Laboratory of Optical Communication Technologies and Networks Wuhan Research Institute of Posts and Telecommunications Wuhan430074 China Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai Institute for Advanced Communication and Data Science Shanghai University Shanghai200072 China School of Electronics and Information Technology Sun Yat-Sen University Guangzhou510275 China

We propose and experimentally demonstrate a simplified direct detection Kramer- Kronig (DD-KK) receiver followed by a Volterra filter to mitigate the SSBI and fiber nonlinearity in a 56-Gb/s optical SSB PAM-4 transmis... 详细信息

ISBN: (纸本)9781943580385

关键词： Pulse amplitude modulation

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