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Envelope Periodic Solutions to Bose-Einstein Condensation in Linear Magnetic Field and Time-Dependent Laser Field

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Communications in Theoretical Physics 2009年第7期52卷 88-90页

作者： gao bin LIU Shi-Kuo LIU Shi-da School of Physics Peking University Beijing 100871 China Department of Physics Yuxi Normal University Yuxi 653100 China

In this paper, by applying the extended 3acobi elliptic function expansion method, the envelope periodic solutions and corresponding dark soliton solution, bright soliton solution to Bose-Einstein condensation in line... 详细信息

关键词： Bose-Einstein condensation Jacobi elliptic function envelope periodic solution soliton solution

Influence of Backbone Structure on Properties of Directly Polymerized Phenoxy Resins from Epichlorohydrin and Various Aromatic Dihydric Phenols Monomers

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Chemical Research in Chinese Universities 2007年第5期23卷 607-612页

作者： CAI Hong-li bi da-wu SHAO Ke ZHONG Shuang-ling NA Hui Alan G. MacDiarmid Institute College of Chemistry Jilin University Changchun 130021 P. R. China

A series of phenoxy resins was directly prepared through the polymerization of each of the various aromatic dihydric phenols and *** and 1H NMR spectra were recorded to characterize the structures of the *** GPC curves were used to determine the molecular weight *** addition,the thermal properties of the resins were studied with differential scanning calorimetry（DSC）and thermal gravimetric analysis（TGA）.The thermal stabilities of the polymers increased with the content of the benzene ring,pendant group increasing or biphenyl groups *** adhesive properties of the polymers were evaluated in terms of the lap shear strength with Fe-Fe *** fracture mechanisms were determined by SEM observation and it was found that there was an important participation of cohesive fracture ***,it has been demonstrated that the extension of these micro-cohesive mechanisms is directly correlated with the adhesive *** to these results,the phenoxy resin containing biphenyl groups presented a higher adhesive strength and could improve the adhesive property of the epoxy/phenoxy system to a certain extent.

关键词： Phenoxy resin Thermal property Adhesive property

Efficient Metric All-k-Nearest-Neighbor Search on datasets Without Any Index

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Journal of Computer Science & Technology 2016年第6期31卷 1194-1211页

作者： Hai-da Zhang Zhi-Hao Xing Lu Chen Yun-Jun gao College of Computer Science Zhejiang University Hangzhou 310027 China School of Computer Science and Engineering The University of New South Wales Sydney 2052 Australia

An all-k-nearest-neighbor （AkNN） query finds k nearest neighbors for each query object. This problem arises naturally in many areas, such as GIS （geographic information system）, multimedia retrieval, and recommender systems. To support various data types and flexible distance metrics involved in real applications, we study AkNN retrieval in metric spaces, namely, metric AkNN （MAkNN） search. Consider that the underlying indexes on the query set and the object set may not exist, which is natural in many scenarios. For example, the query set and the object set could be the results of other queries, and thus, the underlying indexes cannot be built in advance. To support MAkNN search on datasets without any underlying index, we propose an efficient disk-based algorithm, termed as Partition-Based MAkNN Algorithm （PMA）, which follows a partition-search framework and employs a series of pruning rules for accelerating the search. In addition, we extend our techniques to tackle an interesting variant of MAkNN queries, i.e., metric self-AkNN （MSAkNN） search, where the query set is identical to the object set. Extensive experiments using both real and synthetic datasets demonstrate the effectiveness of our pruning rules and the efficiency of the proposed algorithms, compared with state-of-the-art MAkNN and MSAkNN algorithms.

关键词： all-k-nearest-neighbor search query processing metric space

Recent progress in printing flexible electronics: A review

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Science China(Technological Sciences) 2024年第8期67卷 2363-2386页

作者： bi Sheng gao BuHan HAN Xu HE ZhengRan METTS Jacob JIANG ChengMing ASARE-YEBOAH Kyeiwaa Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China Center for Materials for Information Technology The University of AlabamaTuscaloosaAL 35487USA Department of Electrical and Computer Engineering Penn State BehrendEriePA 16563USA

Miniaturization and flexibility are becoming the trend in the development of electronic products. These key features are driving new methods in the manufacturing of such products. Printed electronics technology is a novel additive manufacturing technique that uses active inks to print onto a diverse set of substrates, realizing large-area, low-cost, flexible and green manufacturing of electronic products. These advantageous properties make it extremely compatible with flexible electronics fabrication and extend as far as offering revolutionary methods in the production of flexible electronic devices. In this paper, the details of a printing process system are introduced, including the materials that can be employed as inks, common substrates, and the most recently reported printing strategies. An assessment of future setbacks and developments of printed flexible electronics is also presented.

关键词： flexible electronics printing process conductive ink flexible substrate

Optimizing Multi-Dimensional Packet Classification for Multi-Core Systems

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Journal of Computer Science & Technology 2018年第5期33卷 1056-1071页

作者： Tong Shen da-Fang Zhang gao-Gang Xie Xin-Yi Zhang College of Computer Science and Electronic Engineering Hunan University Changsha 410082 China Network Technology Research Center Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China State Key Laboratory of Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Packet classification has been studied for decades; it classifies packets into specific flows based on a given rule set. As software-defined network was proposed, a recent trend of packet classification is to scale the five-tuple model to multi-tuple. In general, packet classification on multiple fields is a complex problem. Although most existing software-based algorithms have been proved extraordinary in practice, they are only suitable for the classic five-tuple model and difficult to be scaled up. Meanwhile, hardware-specific solutions are inflexible and expensive, and some of them are power consuming. In this paper, we propose a universal multi-dimensional packet classification approach for multi-core systems. In our approach, novel data structures and four decomposition-based algorithms are designed to optimize the classification and updating of rules. For multi-field rules, a rule set is cut into several parts according to the number of fields. Each part works independently. In this way, the fields are searched in parallel and all the partial results are merged together at last. To demonstrate the feasibility of our approach, we implement a prototype and evaluate its throughput and latency. Experimental results show that our approach achieves a 40% higher throughput than that of other decomposed-based algorithms and a 43% lower latency of rule incremental update than that of the other algorithms on average. Furthermore, our approach saves 39% memory consumption on average and has a good scalability.

关键词： multi-dimensional multi-core packet classification

大汶河流域2001—2022年暴雨洪水特征及其关系分析

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水利水运工程学报 2025年第1期 76-86页

作者：贾本有黎东洲杨帆孙晓明高瑾瑾苏琨毕峥峥范子武南京水利科学研究院山东黄河河务局东平湖管理局华北水利水电大学水利学院

科学认识流域实际发生暴雨洪水特征，总结洪水特征及其对致洪暴雨特征响应关系和产汇流规律，对流域洪水精准精细模拟与预报具有重要意义。以大汶河流域为研究区域，基于2001—2022年实测降雨洪水时间序列资料，整理了场次暴雨洪水，选... 详细信息

科学认识流域实际发生暴雨洪水特征，总结洪水特征及其对致洪暴雨特征响应关系和产汇流规律，对流域洪水精准精细模拟与预报具有重要意义。以大汶河流域为研究区域，基于2001—2022年实测降雨洪水时间序列资料，整理了场次暴雨洪水，选取降水空间矩、洪水集中度等指标表征暴雨洪水特征，采用Kendall秩相关分析研究暴雨洪水响应关系，并对流域降水-径流关系进行统计分析。结果表明：（1）大汶河洪水的流域降雨量呈东多西少特征，洪水相应的暴雨事件常覆盖全流域1/3～1/2的面积，暴雨中心多集中在上游大中型水库附近；（2）北支牟汶河子流域洪水总量统计均值大，是大汶河洪水的主要来源，其洪水特征值与致洪暴雨强度呈弱正相关，但与一阶降水空间矩呈负相关，表明子流域内部具有较强的调蓄能力，而南支柴汶河子流域则相反；（3）大汶河流域洪水产流表现为蓄满产流为主、兼有超渗产流的特点，其中大戴区间近22年降雨事件中产流很少，这与其区间特殊的富水性地质条件及灌区引水密切相关，需在流域水文模拟与洪水预报时特别关注。

关键词：场次暴雨洪水 Kendall秩相关分析降雨径流关系产流机制大汶河流域

On the Centenary of the Spanish Flu: Being Prepared for the Next Pandemic

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Virologica Sinica 2018年第6期33卷 463-466页

作者： William J.Liu Yuhai bi dayan Wang George F.gao Chinese National Influenza Center (CNIC) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention (China CDC)Beijing 102206China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research and Early-Warning (CASCIRE)Chinese Academy of SciencesBeijing 100101China

Influenza is one of the oldest infectious diseases affecting humans. Every influenza pandemic in history has ended with disastrous outcomes regarding public health and the social economy. This year marks the 100th anniversary of the Spanish flu (H1N1) outbreak of 1918, which is recognized as the most lethal natural event in recent history.

关键词： Being Prepared for the Next Pandemic On the Centenary of the Spanish Flu

Evaluation of the in-place adsorbed gas content of organic-rich shales using wireline logging data: a new method and its application

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Frontiers of Earth Science 2021年第2期15卷 301-309页

作者： Xin NIE Yu WAN da gao Chaomo ZHANG Zhansong ZHANG Key Laboratory of Exploration Technologies for Oil and Gas Resources Yangtze UniversityWuhan 430100China Cooperative Innovation Center of Unconventional Oil and Gas Yangtze UniversityWuhan 430100China

Adsorbed gas content is an important parameter in shale gas reservoir evaluations,and its common calculation method is based on core ***,in different areas,the correlations between the adsorbed gas content and well logging data might ***,a model developed for one specific area cannot be considered *** on previous studies,we studied the relationships between temperature,TOC,organic matter maturity and adsorbed gas content and revealed qualitative equations between these ***,the equations were combined to establish a new adsorbed gas content calculation model based on depth and total organic carbon(TOC).This model can be used to estimate the adsorbed gas content using only conventional well logging data when core experimental data are rare or even *** method was applied in the southern Sichuan Basin,and the adsorbed gas content results agree well with those calculated using the Langmuir isothermal model and core experimental *** actual data processing results show that the adsorbed gas content model is reliable.

关键词： shale reservoir adsorbed gas well logging temperature pressure TOC depth

Geochemical,mineralogical,and petrological analyses for the interpretation of the sedimentary environment of the Middle-Late Ordovician Majiagou Formation(northern China)as a tool for more effective gas exploration

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Petroleum Science 2022年第6期19卷 2519-2532页

作者： Jie gao da-Wei Lv A.J.(Tom) van Loon Dun Wu Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdaoShandong266590China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyShandong266071China College of Earth Science and Engineering Shandong University of Science and TechnologyShandong266590China Exploration Research Institute Anhui Provincial Bureau of Coal GeologyHefeiAnhui230088China

Core samples from the deeply buried Ordovician Majiagou Formation below the Huainan Coalfield(E China) have been investigated for their carbonate types,major and trace elements(including rare earth elements) and C and O isotopes,The objective was to get a better insight into the possible occurrences of gas(and possibly oil) derived from Carboniferous *** was found that the carbonates are dolomites with strongly varying amounts of CaO and *** low concentrations of SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)indicate deposition in a normal marine environment with little terrigenous input,The Na_(2)O/K_(2)O,Fe/Mn and Sr/Ba ratios,as well as the Ga values indicate mainly a marine salinity and a hot and humid *** slight depletion of Ce and Eu,the depletion of heavy rare earth elements(HREE) and the enrichment of light rare earth elements(LREE) indicate deposition in a reducing *** thus appears that the Majiagou Formation below the Huainan Coalfield closely resembles that in the eastern part of the Ordos Basin,where several gas reservoirs are present,so that the Majiagou Formation under the Huainan Coalfield represents a promising target for hydrocarbon exploration.

关键词： Majiagou Formation Middle Ordovician Major-element analysis REE analysis Trace-element analysis Hydrocarbon exploration