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Revenue-maximizing online stable task assignment on taxi-dispatching platforms

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Frontiers of Computer Science 2022年第6期16卷 175-177页

作者： Jingwei LV Ze ZHAO shuzhen yao Weifeng LV School of Computer Science and Engineering Beihang UniversityBeijing100191China School of Mathematical Science Beihang UniversityBeijing100191China

1 Introduction and contributions With the rapid development of mobile Internet,taxi-dispatching platforms have become increasingly popular and *** example,UBer and Didi are both famous O2O platforms covering the dominating portion of the taxidispatching market over the world.A central issue in taxidispatching platforms is task assignment.

关键词： O2O assignment platforms

Geochemistry, U-Pb Geochronology and Sr-Nd-Hf Isotopes of the Early Cretaceous Volcanic Rocks in the Northern Da Hinggan Mountains

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 203-216页

作者： HU Xinlu yao shuzhen HE Mouchun DING Zhenju CHEN Bin Faculty of Earth Resources China University of Geosciences Key Laboratory of Tectonics and Petroleum Resources Ministry of Education State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences

Whole-rock geochemical, zircon U-Pb geochronological and Sr-Nd-Hf isotopic data are presented for the Early Cretaceous volcanic rocks from the northern Da Hinggan Mountains. The volcanic rocks generally display high SiO2 （73.19-77.68 wt%） and Na20＋K20 （6.53-8.98 wt%） contents, with enrichment in Rb, Th, U, Pb and LREE, and depletion in Nb, Ta, P and Ti. Three rhyolite samples, one rhyolite porphyry sample, and one volcanic breccia sample yield weighted mean 206pb/23SU ages of 135.1±1.2 Ma, 116.5±1.1 Ma, 121.9±1.0 Ma, 118.1±0.9 Ma and 116.9±1.4 Ma, respectively. All these rocks have moderate （STSr/S6Sr）i values of 0.704912 to 0.705896, slightly negative eNd（t） values of -1.4 to -0.1, and positive Cur（t） values of 3.7 to 8. Their zircon Hf and whole-rock Nd isotopic model ages range from 594 to 1024 Ma. These results suggest that the Early Cretaceous volcanic rocks were originated from melting of subducted oceanic crust and associated sediments during the closure of the Mongol-Okhotsk Ocean.

关键词： U-Pb geochronology Sr-Nd-Hf isotopes volcanic rocks Early Cretaceous Da HingganMountains

Structural Control of the Getang Carlin-Type Gold Deposit in Southwest China

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Journal of Earth Science 2024年第2期35卷 536-552页

作者： Guoping Zeng Xinlu Hu Diwei Luo Jianzhong Liu shuzhen yao Yongjie Jin Wuhan Center China Geological SurveyWuhan430205China Central South China Innovation Center for Geosciences Wuhan430205China Faculty of Earth Resources China University of GeosciencesWuhan430074China Geological Party 105 Guizhou Bureau of Geology and Mineral Exploration&DevelopmentGuiyang550018China

The Getang is a representative Carlin-type gold deposit in Southwest *** has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t *** orebodies occur as strat-abound lenses,and are structurally controlled by shallow NWW-and NE-trending fold-fault systems and the unconformity between the Upper and Middle *** this study,the regional-and deposit-scale structural investigations,joints and finite strain measurements,and stress and dynamic analysis were conducted with an aim to reveal the structural process of the Getang gold deposit and clarify the relationship between the gold mineralization and *** phases of deformation were identified in the deposit:(1)paleokarst was generated by a crustal uplift when the Youjiang Basin experienced extension at the end of the Middle Permian,laying the foundation for the unconformity;(2)the NW-trending structures were formed under a NNE-SSW compression during the Indochina-South China collision(Indosinian orogeny)in Triassic;(3)the NE-trending structures were generated or reactivated under a NW-SE-oriented compression during the Yanshanian intracontinental *** unconformity recorded two episodes of tectonic evolution in the NNE-SSW and NW-SE *** analyses and geochronology data suggest that the Getang gold deposit was formed as a result of tectonic transition from compression to extension during the Yanshanian intracontinental orogeny.

关键词： Carlin-type gold deposit structural features finite strain Getang Southwest China economy geology geochemistry

On Magma-Genetic Characteristics of Skarn and Its Formation Mechanism

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Journal of Earth Science 1993年第1期12卷 74-79,139页

作者： Lin Xinduo Zhang shuzhen Xu GuqjianChina University of Geosciences , Wuhan 430074 Zhang Chuanling , yao shuzhen and Zhang Dehui also participated in this study .

For skarn type deposits , there are two lands of skarns , skarn formed by filtrating-diffusing metasomatism and vein skarn formed by filling . The vein skarn , discussed this paper and considered to be magmatic genesis , is characterized by: (1) occurring as vein with distinct boundaries with country rocks , yet just the same even in marble easy to be replaced ; (2) composed of a mineral assemblage similar to that of granite ,containing pegmatite as wen as coarse skarn mineral pockets ,and sometimes transited with dike rocks ; (3) dear crystalline feature of deposition ; (4) sideronitic texture ; (5) stowing vesicular, bean-like and flow structures ; (6) very common liquid immiscibility; (7) vertical zoning of gravitational differentiation caused by volatile concentration upwards; (8) associated and transited with non-copper ore bodies of magmatic genesis and tungsten-bearing quartz veins of silicate magmatic genesis rich in volatile ; (9) melt inclusions . Two origins of skam magma . originated by assimilation of silicate magma at its emplacemeot or below it and generated owe to assimilation of deep magma ,corrosion of carbonate strata and liquation , are presented .

关键词： skam skam magma ore magma .liquid immiscibility.

基于Petri网的UML状态图的形式化模型

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北京航空航天大学学报 2007年第2期33卷 248-252页

作者：郭峰姚淑珍北京航空航天大学计算机学院北京100083

提出一种可以准确描述UML状态图动态特征的形式化模型SC_Net.首先给出了UML状态图的形式化语法定义,其中用状态集合、转移集合、事件集合、条件集合、活动集合、对象集合和变量集合,定义了一系列辅助函数描述UML状态图特征,用确定目标... 详细信息

提出一种可以准确描述UML状态图动态特征的形式化模型SC_Net.首先给出了UML状态图的形式化语法定义,其中用状态集合、转移集合、事件集合、条件集合、活动集合、对象集合和变量集合,定义了一系列辅助函数描述UML状态图特征,用确定目标状态和受限源状态表示层次关系,用开放事件和封闭事件表示对象之间的消息.基于C_Net定义了描述UML状态图动态语义的Petri网模型SC_Net,既能描述状态图中的控制部分,又能描述状态图中的数据处理部分,并给出了从UML状态图到SC_Net的转换步骤,便于实现自动转换过程.最后以柔性制造系统的一个实例说明SC_Net能用于分析UML状态图的性质.

关键词： UML状态图 Petri网形式化语义

Thermodynamic Modeling of Fluid-Bearing Natural Gas Inclusions for Geothermometer and Geobarometer of Overpressured Environments in Qiongdongnan Basin, South China Sea

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Journal of China University of Geosciences 2002年第3期13卷 240-247页

作者： Chen Honghan yao shuzhen Wang Jiahao Li Chunquan Institute of Resources, China University of Geosciences, Wuhan 430074 Institute of Resources China University of Geosciences Wuhan 430074

It is a very difficult problem to directly determine fluid pressure duringhydrocarbon migration and accumulation in sedimentary basins. pVt modeling of coupling hydrocarbonfluid inclusion of its coeval aqueous fluid inclusion provides a powerful tool for establishing therelationship of formation pressure evolution with time. Homogenization temperature of fluidinclusion can routinely be measured under microthermometric microscopy. Crushing technique has beenemployed to obtain the composition of fluid inclusions, and the commercial software VTFLINC easilyand rapidly completes the construction of p-t phase diagram. The minimum trapping pressure ofhydrocarbon fluid inclusion would be then determined in the p-t space. In this paper, three samplesof YC21-1-1 and YC21-1-4 wells at YC21-1 structural closure, Qiongdongnan basin, South China Sea,were selected for the pVt modeling practice, and the formation pressure coefficient (equals to fluidpressure/hydrostatic pressure) changing trend with time has primarily been established. Themodeling results also indicate that the reservoirs of Ling-shui and Yacheng formations in YC21-1structure are within a very high potential system and would have undergone a discharging of thermalfluids through top seal rupture, which depicts that there is a very high risk for natural gasexploration in this area.

关键词： hydrocarbon fluid inclusion pVt modeling natural gas migration andaccumulation qiongdongnan basin south china sea

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用对象实现构件的原型开发方法

计算机科学 1995年第4期22卷 66-68,78页

作者：姚淑珍北京航空航天大学计算机系北京100083

1.引言原型开发方法是针对传统的瀑布式开发方法弊端,为充分获取用户需要而提出来~[1]。原型开发方法是指开发者获取用户最初需求后。

关键词：原型开发法构件软件开发

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UML状态图的形式化建模及其分析

北京航空航天大学学报 2007年第4期33卷 472-476页

作者：姚淑珍金茂忠北京航空航天大学计算机学院北京100083

为解决状态图的建模问题,特别是带有复合状态的层次化状态图的建模问题,分析了UML状态图的结构特点和语义特征,构造了层次化着色Petri网HCPN.将复合状态的Petri网子网结构划分成输入/输出端口、状态迁移部分和历史状态部分.其中输入/输... 详细信息

为解决状态图的建模问题,特别是带有复合状态的层次化状态图的建模问题,分析了UML状态图的结构特点和语义特征,构造了层次化着色Petri网HCPN.将复合状态的Petri网子网结构划分成输入/输出端口、状态迁移部分和历史状态部分.其中输入/输出端口分别用于完成子网进入弧的解析和离开的弧的汇总,状态迁移部分完成状态机子网内部状态变换,历史状态部分通过“记忆单元”,完成复合状态的“记忆恢复”和“记忆刷新”.基于所构造的HCPN结构,总结了状态图复合状态转入/转出迁移的语义和约束规则,阐述了复合状态的Petri网子网的相应描述方法和分析技术.最后针对状态图的安全性要求详细论述了历史状态完备性判定原则、父子层一致性判定原则和状态可达性判定原则的HCPN语义表示.研究成果对进一步开发自动化分析验证工具,优化复杂系统设计方案,提高软件质量具有重要的指导意义.

关键词：建模 Petri网语义分析

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基于Petri网的UML状态迁移策略

北京航空航天大学学报 2008年第1期34卷 79-83页

作者：姚淑珍金茂忠北京航空航天大学计算机学院北京100083

分析了统一建模语言(UML,Unified Modeling Language)状态图相关语义,阐述了Petri网基本特征和它所具有的建模事件并发、同步、冲突能力.为得到UML状态图无二义性的、可执行的和可验证的模型,在着色Petri网和层次化Petri网研究成果基础... 详细信息

分析了统一建模语言(UML,Unified Modeling Language)状态图相关语义,阐述了Petri网基本特征和它所具有的建模事件并发、同步、冲突能力.为得到UML状态图无二义性的、可执行的和可验证的模型,在着色Petri网和层次化Petri网研究成果基础上,研究提出层次着色Petri网(HCPN,Hierarchical Colored Petri Net).HCPN中不同层的着色网CPN通过库所子网或变迁子网相关联.通过实例说明如何借助这些关联从HCPN中的CPN合并得到标注Petri网.标注Petri网可用于指导基于事件驱动的仿真过程,而标注Petri网转换得到的基本Petri网可用来进行特性分析,从而对所描述的UML状态图模型给出合理的评价,有利于建模系统的改进.

关键词： Petri网面向对象编程层次化系统合成