Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW ...Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW research,we conducted a bibliometric analysis and employed knowledge graph visualization to scrutinize a total of 34212 articles,which were published between 1991 and 2021 in the Web of Science(WoS)core database.The results indicated that current major research themes encompass waste classifica-tion and recycling,waste management and public behavior,waste disposal methods and technologies,as well as environmental impact and evaluation.There has been a shift in the research focus from the environmental impacts of waste incineration to sustainable manage-ment related issues.A comparison of research from six typical countries revealed the differences in research priorities and techniques advantages.Scholars from the USA and Britain initiated MW research earlier than other countries and investigated management issues in depth,such as public behavior and willingness to pay.Meanwhile,Japanese,German,and Swedish scholars conducted extensive studies on advanced waste treatment technologies,such as disposal and recycling,risk assessment,and waste-to-energy techniques.Chinese scholars placed particular emphasis on end-of-pipe treatments and their associated environmental impacts.Hotspots and poten-tial future frontiers were identified by burst detection analysis.Keywords with high value of burst index(BI)worldwide are food waste and circular economy.Chinese scholars have put great efforts on waste environmental impact and its recycling technologies,while we’re expecting to further investigating vulnerable population.Furthermore,this study contributes to bridging the regional gap of scientific research among different countries and fostering international collaboration.展开更多
To address the imbalance problem between supply and demand for taxis and passengers,this paper proposes a distributed ensemble empirical mode decomposition with normalization of spatial attention mechanism based bi-di...To address the imbalance problem between supply and demand for taxis and passengers,this paper proposes a distributed ensemble empirical mode decomposition with normalization of spatial attention mechanism based bi-directional gated recurrent unit(EEMDN-SABiGRU)model on Spark for accurate passenger hotspot prediction.It focuses on reducing blind cruising costs,improving carrying efficiency,and maximizing incomes.Specifically,the EEMDN method is put forward to process the passenger hotspot data in the grid to solve the problems of non-smooth sequences and the degradation of prediction accuracy caused by excessive numerical differences,while dealing with the eigenmodal EMD.Next,a spatial attention mechanism is constructed to capture the characteristics of passenger hotspots in each grid,taking passenger boarding and alighting hotspots as weights and emphasizing the spatial regularity of passengers in the grid.Furthermore,the bi-directional GRU algorithm is merged to deal with the problem that GRU can obtain only the forward information but ignores the backward information,to improve the accuracy of feature extraction.Finally,the accurate prediction of passenger hotspots is achieved based on the EEMDN-SABiGRU model using real-world taxi GPS trajectory data in the Spark parallel computing framework.The experimental results demonstrate that based on the four datasets in the 00-grid,compared with LSTM,EMDLSTM,EEMD-LSTM,GRU,EMD-GRU,EEMD-GRU,EMDN-GRU,CNN,and BP,the mean absolute percentage error,mean absolute error,root mean square error,and maximum error values of EEMDN-SABiGRU decrease by at least 43.18%,44.91%,55.04%,and 39.33%,respectively.展开更多
目的了解近10年难治性高血压(resistant hypertension,RH)的研究热点、研究前沿及发展趋势。方法收集Web of Science核心合集数据库中2012-2021年有关RH的文献,利用CiteSpace软件分别以作者、国家、机构和关键词作为节点进行共现分析,...目的了解近10年难治性高血压(resistant hypertension,RH)的研究热点、研究前沿及发展趋势。方法收集Web of Science核心合集数据库中2012-2021年有关RH的文献,利用CiteSpace软件分别以作者、国家、机构和关键词作为节点进行共现分析,对被引期刊和参考文献进行共被引分析,并对关键词进行聚类分析和动态前沿演化分析。结果共纳入2257篇文献,年均发文量约220篇;发文量排名前5的作者依次是FELIX MAHFOUD(89篇)、MICHAEL BOEHM(73篇)、ROLAND E SCHMIEDER(63篇)、DAVID A CALHOUN(49篇)和SUZANNE OPARIL(38篇);发文最多的国家和机构分别是美国和Univ Alabama Birmingham;研究成果被引最多的期刊是HYPERTENSION;对132个高频关键词进行聚类分析,共形成5个聚类标签。结论近10年来RH的发文量总体呈上升趋势,研究内容逐渐丰富,此次研究相对直观地揭示了可合作的研究者及机构,并对研究热点进行了预测,为了解RH这一领域的发展方向和研究选题等提供了一定参考。展开更多
Hotspot topic trends can be captured by analyzing user attributes and historical behavior in social network. In this paper, we propose a user participation behavior prediction model for social hotspots, based on user ...Hotspot topic trends can be captured by analyzing user attributes and historical behavior in social network. In this paper, we propose a user participation behavior prediction model for social hotspots, based on user behavior and relationship data, to predict user participation behavior and topic development trends. Firstly, for the complex factors of user behavior, three dynamic influence factor functions are defined, including individual, peer and community influence. These functions take timeliness into account using a time discretization method. Secondly, to determine laws of individual behavior and group behavior within a social topic, a hotspot user participation behavior prediction model is proposed and associated with the basic concepts of randora field and Markov property in information diffusion. The experimental results show that the model can not only dynamically predict the individual behavior, but also grasp the development trends of topics.展开更多
采用Relim算法对科技文献数据进行热点主题词挖掘,利用时间序列集成实现未来一段时间的热点主题词预测。从Web of Science数据库中采集2000—2017年动物遗传与育种领域相关的71990研究论文作为研究对象,运用频繁项集算法Relim,对该领域...采用Relim算法对科技文献数据进行热点主题词挖掘,利用时间序列集成实现未来一段时间的热点主题词预测。从Web of Science数据库中采集2000—2017年动物遗传与育种领域相关的71990研究论文作为研究对象,运用频繁项集算法Relim,对该领域的热点研究主题进行识别研究,并利用时间序列集成方法对热点研究主题在未来一段时间内的演变趋势进行预测。结果表明,该方法能较好地对某一个领域的热点主题词进行预测,且集成后的预测模型对时间序列预测效果较好,可帮助科研人员和政策制定者了解特定学科领域的主题热点状况。展开更多
Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts...Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts for most of the protein-protein binding free energy. Computational methods play a critical role in identifying the hotspots on the proteinprotein interface. In this paper, we use a computational alanine scanning method with all-atom force fields for predicting hotspots for 313 mutations in 16 protein complexes of known structures. We studied the effect of force fields, solvation models, and conformational sampling on the hotspot predictions. We compared the calculated change in the protein-protein interaction energies upon mutation of the residues in and near the protein-protein interface, to the experimental change in free energies. The AMBER force field (FF) predicted 86% of the hotspots among the three commonly used FF for proteins, namely, AMBER FF, Charmm27 FF, and OPLS-2005 FF. However, AMBER FF also showed a high rate of false positives, while the Charmm27 FF yielded 74% correct predictions of the hotspot residues with low false positives. Van der Waals and hydrogen bonding energy show the largest energy contribution with a high rate of prediction accuracy, while the desolvation energy was found to contribute little to improve the hot spot prediction. Using a conformational ensemble including limited backbone movement instead of one static structure leads to better predicttion of hotpsots.展开更多
基金Under the auspices of the General Program of National Natural Science Foundation of China(No.42271112)General Research Project of Beijing Municipal Commission of Education Science(No.KM202011417008)。
文摘Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW research,we conducted a bibliometric analysis and employed knowledge graph visualization to scrutinize a total of 34212 articles,which were published between 1991 and 2021 in the Web of Science(WoS)core database.The results indicated that current major research themes encompass waste classifica-tion and recycling,waste management and public behavior,waste disposal methods and technologies,as well as environmental impact and evaluation.There has been a shift in the research focus from the environmental impacts of waste incineration to sustainable manage-ment related issues.A comparison of research from six typical countries revealed the differences in research priorities and techniques advantages.Scholars from the USA and Britain initiated MW research earlier than other countries and investigated management issues in depth,such as public behavior and willingness to pay.Meanwhile,Japanese,German,and Swedish scholars conducted extensive studies on advanced waste treatment technologies,such as disposal and recycling,risk assessment,and waste-to-energy techniques.Chinese scholars placed particular emphasis on end-of-pipe treatments and their associated environmental impacts.Hotspots and poten-tial future frontiers were identified by burst detection analysis.Keywords with high value of burst index(BI)worldwide are food waste and circular economy.Chinese scholars have put great efforts on waste environmental impact and its recycling technologies,while we’re expecting to further investigating vulnerable population.Furthermore,this study contributes to bridging the regional gap of scientific research among different countries and fostering international collaboration.
基金Project supported by the National Natural Science Foundation of China(Nos.62162012,62173278,and 62072061)the Science and Technology Support Program of Guizhou Province,China(No.QKHZC2021YB531)+3 种基金the Natural Science Research Project of Department of Education of Guizhou Province,China(Nos.QJJ2022015 and QJJ2022047)the Science and Technology Foundation of Guizhou Province,China(Nos.QKHJCZK2022YB195,QKHJCZK2022YB197,and QKHJCZK2023YB143)the Scientific Research Platform Project of Guizhou Minzu University,China(No.GZMUSYS202104)the 7^(th) Batch High-Level Innovative Talent Project of Guizhou Province,China。
文摘To address the imbalance problem between supply and demand for taxis and passengers,this paper proposes a distributed ensemble empirical mode decomposition with normalization of spatial attention mechanism based bi-directional gated recurrent unit(EEMDN-SABiGRU)model on Spark for accurate passenger hotspot prediction.It focuses on reducing blind cruising costs,improving carrying efficiency,and maximizing incomes.Specifically,the EEMDN method is put forward to process the passenger hotspot data in the grid to solve the problems of non-smooth sequences and the degradation of prediction accuracy caused by excessive numerical differences,while dealing with the eigenmodal EMD.Next,a spatial attention mechanism is constructed to capture the characteristics of passenger hotspots in each grid,taking passenger boarding and alighting hotspots as weights and emphasizing the spatial regularity of passengers in the grid.Furthermore,the bi-directional GRU algorithm is merged to deal with the problem that GRU can obtain only the forward information but ignores the backward information,to improve the accuracy of feature extraction.Finally,the accurate prediction of passenger hotspots is achieved based on the EEMDN-SABiGRU model using real-world taxi GPS trajectory data in the Spark parallel computing framework.The experimental results demonstrate that based on the four datasets in the 00-grid,compared with LSTM,EMDLSTM,EEMD-LSTM,GRU,EMD-GRU,EEMD-GRU,EMDN-GRU,CNN,and BP,the mean absolute percentage error,mean absolute error,root mean square error,and maximum error values of EEMDN-SABiGRU decrease by at least 43.18%,44.91%,55.04%,and 39.33%,respectively.
文摘目的了解近10年难治性高血压(resistant hypertension,RH)的研究热点、研究前沿及发展趋势。方法收集Web of Science核心合集数据库中2012-2021年有关RH的文献,利用CiteSpace软件分别以作者、国家、机构和关键词作为节点进行共现分析,对被引期刊和参考文献进行共被引分析,并对关键词进行聚类分析和动态前沿演化分析。结果共纳入2257篇文献,年均发文量约220篇;发文量排名前5的作者依次是FELIX MAHFOUD(89篇)、MICHAEL BOEHM(73篇)、ROLAND E SCHMIEDER(63篇)、DAVID A CALHOUN(49篇)和SUZANNE OPARIL(38篇);发文最多的国家和机构分别是美国和Univ Alabama Birmingham;研究成果被引最多的期刊是HYPERTENSION;对132个高频关键词进行聚类分析,共形成5个聚类标签。结论近10年来RH的发文量总体呈上升趋势,研究内容逐渐丰富,此次研究相对直观地揭示了可合作的研究者及机构,并对研究热点进行了预测,为了解RH这一领域的发展方向和研究选题等提供了一定参考。
基金supported by the National Key Basic Research Program(973 program)of China(No.2013CB329606)National Science Foundation of China(Grant No.61272400)+2 种基金Science and Technology Research Program of the Chongqing Municipal Education Committee(No.KJ1500425)Wen Feng Foundation of CQUPT(No.WF201403)Chongqing Graduate Research And Innovation Project(No.CYS14146)
文摘Hotspot topic trends can be captured by analyzing user attributes and historical behavior in social network. In this paper, we propose a user participation behavior prediction model for social hotspots, based on user behavior and relationship data, to predict user participation behavior and topic development trends. Firstly, for the complex factors of user behavior, three dynamic influence factor functions are defined, including individual, peer and community influence. These functions take timeliness into account using a time discretization method. Secondly, to determine laws of individual behavior and group behavior within a social topic, a hotspot user participation behavior prediction model is proposed and associated with the basic concepts of randora field and Markov property in information diffusion. The experimental results show that the model can not only dynamically predict the individual behavior, but also grasp the development trends of topics.
文摘采用Relim算法对科技文献数据进行热点主题词挖掘,利用时间序列集成实现未来一段时间的热点主题词预测。从Web of Science数据库中采集2000—2017年动物遗传与育种领域相关的71990研究论文作为研究对象,运用频繁项集算法Relim,对该领域的热点研究主题进行识别研究,并利用时间序列集成方法对热点研究主题在未来一段时间内的演变趋势进行预测。结果表明,该方法能较好地对某一个领域的热点主题词进行预测,且集成后的预测模型对时间序列预测效果较好,可帮助科研人员和政策制定者了解特定学科领域的主题热点状况。
文摘Protein-protein complexes play an important role in the physiology and the pathology of cellular functions, and therefore are attractive therapeutic targets. A small subset of residues known as “hot spots”, accounts for most of the protein-protein binding free energy. Computational methods play a critical role in identifying the hotspots on the proteinprotein interface. In this paper, we use a computational alanine scanning method with all-atom force fields for predicting hotspots for 313 mutations in 16 protein complexes of known structures. We studied the effect of force fields, solvation models, and conformational sampling on the hotspot predictions. We compared the calculated change in the protein-protein interaction energies upon mutation of the residues in and near the protein-protein interface, to the experimental change in free energies. The AMBER force field (FF) predicted 86% of the hotspots among the three commonly used FF for proteins, namely, AMBER FF, Charmm27 FF, and OPLS-2005 FF. However, AMBER FF also showed a high rate of false positives, while the Charmm27 FF yielded 74% correct predictions of the hotspot residues with low false positives. Van der Waals and hydrogen bonding energy show the largest energy contribution with a high rate of prediction accuracy, while the desolvation energy was found to contribute little to improve the hot spot prediction. Using a conformational ensemble including limited backbone movement instead of one static structure leads to better predicttion of hotpsots.
