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Verifying Functions in Online Stock Trading Systems

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Journal of Computer Science & Technology 2004年第2期19卷 203-212页

作者： Yu-yuedu Chang-JunJiang DepartmentofComputerScience Liaochen9UniversityLiaochen9252059P.R.China

Temporal colored Petri nets, an extension of temporal Petri nets, areintroduced in this paper. It can distinguish the personality of individuals (tokens), describeclearly the causal and temporal relationships between events in concurrent systems, and representelegantly certain fundamental properties of concurrent systems, such as eventuality and *** use of this method is illustrated with an example of modeling and formal verification of anonline stock trading system. The functional correctness of the modeled system is formally verifiedbased on the temporal colored Petri net model and temporal assertions. Also, some main properties ofthe system are analyzed. It has been demonstrated sufficiently that temporal colored Petri nets canverify efficiently some time-related properties of concurrent systems, and provide both the powerof dynamic representation graphically and the function of logical inference formally. Finally,future work is described.

关键词： formal modeling verification online stock trading system function coloredPetri net temporal logic

超临界CO_(2)作用下无烟煤结构响应特征及高压吸附机理

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天然气工业 2024年第4期44卷 115-125页

作者：王建美梁卫国牛栋陈跃都王聪伟贺伟原位改性采矿教育部重点实验室·太原理工大学太原理工大学矿业工程学院太原师范学院碳中和研究院中国科学院山西煤炭化学研究所

中国深部煤层气资源丰富,将CO_(2)注入深部煤层,在提高煤层气采收率同时,还可实现CO_(2)地质封存(CO_(2)-ECBM)。通常,深部煤层CO_(2)处于超临界态并显著影响煤体吸附能力,但对于超临界CO_(2)作用下煤体结构演化及吸附机理尚不清晰。为... 详细信息

中国深部煤层气资源丰富,将CO_(2)注入深部煤层,在提高煤层气采收率同时,还可实现CO_(2)地质封存(CO_(2)-ECBM)。通常,深部煤层CO_(2)处于超临界态并显著影响煤体吸附能力,但对于超临界CO_(2)作用下煤体结构演化及吸附机理尚不清晰。为此,以山西晋城成庄矿二叠系山西组三号煤层为研究对象,开展了无烟煤对超临界CO_(2)的高压吸附实验,结合傅里叶变换红外光谱(FTIR)、X射线衍射光电子能谱(XPS)测试及比表面积(BET)测试,分析了超临界CO_(2)高压吸附引起的无烟煤化学结构与孔隙结构响应特征,最后揭示了无烟煤对超临界CO_(2)的高压吸附特性及吸附机理。研究结果表明:①超临界CO_(2)高压吸附存在突变点,35℃时突变点位于临界压力(8 MPa)附近,在突变点处的吸附能力最小;②超临界CO_(2)可使芳香环枝接官能团、醚氧键、羟基氢键断裂,脂肪结构甲基脱落,可为CO_(2)提供更多的吸附位点,增强了无烟煤表面吸附能力;③超临界CO_(2)改变无烟煤介孔的孔隙结构特征和分形特征,吸附后平均孔径、孔体积、比表面积、分形维数呈增大趋势,孔隙粗糙度增大,对孔隙结构改造作用表现为“增孔、扩孔、粗糙化”,可提供更多吸附空间,增强了无烟煤吸附能力;④在深部煤层中注入CO_(2),应优先选择高孔隙度、高渗透性储层,注入煤层环境应尽可能远离CO_(2)临界点区域,储层对CO_(2)才有最大吸附能力。结论认为,成果认识为深部煤层CO_(2)可注性及封存潜力评估提供了重要的理论依据,对煤层气高效开发具有重要现实意义。

关键词： CO_(2)-ECBM 超临界CO_(2) 高压吸附特性化学结构孔隙结构无烟煤封存可注性

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Convective heat transfer of water flow in intersected rock fractures for enhanced geothermal extraction

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 108-122页

作者： yuedu Chen Zhihong Zhao Huan Peng Department of Civil Engineering Tsinghua UniversityBeijing100084China

Numerous intersected rock fractures constitute the fracture network in enhanced geothermal *** complicated convective heat transfer behavior in intersected fractures is critical to the heat recovery in fractured geothermal reservoirs.A series of three-dimensional intersected fracture models is constructed to perform the flow-through heat transfer *** geometry effects of dead-end fractures(DEFs)on the heat transfer are evaluated in terms of intersected angles,apertures,lengths,and the *** results indicate that annular streamlines appear in the rough DEF and cause an ellipse distribution of the cold *** to plate DEFs,the fluid flow in the rough DEF enhances the heat *** the increment of outlet water temperatureΔToutand the ratio of heat production Qrpresent the largest at the intersected angle of 90°while decline with the decrease of the intersected angle between the main flow fracture(MFF)and the *** extension of the length of intersected DEFs is beneficial to heat production while enhancing its aperture is not *** increasing the number of intersected DEFs induces a little increase of heat extraction,and more significant heat production can be obtained through connecting these DEFs with the MFF forming the flow network.

关键词： Heat transfer Fracture intersection Fluid flow Rough fracture Geothermal extraction

区间温度循环作用后花岗岩抗拉强度演化特征试验研究

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矿业研究与开发 2024年第8期44卷 23-30页

作者：赵文艳黄长松陈跃都王凯飞张扬山西工程职业学院资源与安全工程系山西太原030009 太原理工大学原位改性采矿教育部重点实验室山西太原030024 中煤科工集团武汉设计研究院有限公司湖北武汉430064 中国三峡建工(集团)有限公司四川成都610041

为揭示300~150℃循环热处理后花岗岩物理性质及抗拉强度演变规律,对经过不同热处理循环次数的花岗岩自然吸水率、纵波波速变化进行测定,并开展巴西劈裂试验,期间采用声发射技术监测其破坏过程的声发射特征。结果表明:(1)花岗岩经历300~... 详细信息

为揭示300~150℃循环热处理后花岗岩物理性质及抗拉强度演变规律,对经过不同热处理循环次数的花岗岩自然吸水率、纵波波速变化进行测定,并开展巴西劈裂试验,期间采用声发射技术监测其破坏过程的声发射特征。结果表明:(1)花岗岩经历300~150℃循环热处理后,自然吸水率增大,变化量在0.25%~0.35%,纵波波速降低,衰减量为1132.3~1199.6 m/s;(2)花岗岩抗拉强度随热处理次数增多呈指数型减小,室温-300℃-室温处理方式下花岗岩抗拉强度最低,为13.21 MPa,而300~150℃循环热处理下,抗拉强度较室温-300℃-室温处理方式有所提高;(3)与室温条件相比,循环热处理后花岗岩加载至破坏所用时间呈降低趋势,且峰值荷载前出现声发射累计能量突变及振铃数峰值现象;(4)花岗岩经过300~150℃循环热处理后,破坏时监测的声发射累计能量和波速损伤变量与循环次数的变化趋势相反。研究成果可为一定温度区间循环下花岗岩物理力学演变行为提供参考。

关键词：温度循环巴西劈裂声发射抗拉强度人工热储层

Unloading-induced permeability recovery in rock fractures

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3148-3162页

作者： Tao Lin Wen Meng yuedu Chen Zhihong Zhao Bing Liu Jintong Zhang Sicong Chen Xingguang Zhao Department of Civil Engineering Tsinghua UniversityBeijingChina Key Laboratory of Neotectonic Movement and Geohazard Institute of GeomechanicsChinese Academy of Geological SciencesBeijingChina College of Mining Engineering Taiyuan University of TechnologyTaiyuanChina CNNC Key Laboratory on Geological Disposal of High-level Radioactive Waste Beijing Research Institute of Uranium GeologyBeijingChina

Underground space creation and energy extraction, which induce unloading on rock fractures, commonly occur in various rock engineering projects, and rock engineering projects are subjected to high temperatures with increasing depth. Fluid flow behavior of rock fractures is a critical issue in many subsurface rock engineering projects. Previous studies have extensively considered permeability evolution in rock fractures under loading phase, whereas changes in fracture permeability under unloading phase have not been fully understood. To examine the unloading-induced changes in fracture permeability under different temperatures, we performed water flow-through tests on fractured rock samples subjected to decreasing confining pressures and different temperatures. The experimental results show that the permeability of fracture increases with unloading of confining pressure but decreases with loading-unloading cycles. Temperature may affect fracture permeability when it is higher than a certain threshold. An empirical model of fracture hydraulic aperture including two material parameters of initial normal stiffness and maximum normal closure can well describe the permeability changes in rough rock fracture subjected to loading-unloading cycles and heating. A coupled thermo-mechanical model considering asperity damage is finally used to understand the influences of stress paths and temperatures on fracture permeability.

关键词： Unloading Permeability Rock fracture Temperature Empirical model

The role of temperature‐enhanced fault closure in promoting postinjection pressure diffusion and seismicity in enhanced geothermal systems

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Deep Underground Science and Engineering 2023年第4期2卷 394-405页

作者： Yinlin Ji yuedu Chen Hannes Hofmann Yuan Zhang Arno Zang Günter Zimmermann Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences PotsdamGermany Key Laboratory of In‐situ Property‐improving Mining of Ministry of Education Taiyuan University of TechnologyTaiyuanChina Institute of Applied Geosciences Technische Universität BerlinBerlinGermany Key Laboratory of Deep Coal Resource Mining(CUMT) Ministry of EducationSchool of MinesChina University of Mining and TechnologyXuzhouChina

Post shut‐in seismic events in enhanced geothermal systems(EGSs)occur predominantly at the outer rim of the co‐injection seismic *** concept of postinjection fracture and fault closure near the injection well has been proposed and validated as a mechanism for enhancing post shut‐in pressure diffusion that promotes seismic *** phenomenon is primarily attributed to the poro‐elastic closure of fractures resulting from the reduction of wellbore pressure after injection ***,the thermal effects in EGSs,mainly including heat transfer and thermal stress,may not be trivial and their role in postinjection fault closure and pressure evolution needs to be *** this study,we performed numerical simulations to analyze the relative importance of poro‐elasticity,heat transfer,and thermo‐elasticity in promoting postinjection fault closure and pressure *** numerical model wasﬁrst validated against analytical solutions in terms ofﬂuid pressure diffusion and against heatedﬂow‐through experiments in terms of thermal *** then quantiﬁed and distinguished the contribution of each individual mechanism by comparing four different shut‐in scenarios simulated under different coupled *** results highlight the importance of poro‐elastic fault closure in promoting postinjection pressure buildup and seismicity,and suggest that heat transfer can further augment the fault closure‐induced pressure increase and thus potentially intensify the postinjection seismic hazard,with minimal contribution from thermo‐elasticity.

关键词： enhanced geothermal system(EGS) fault closure hydraulic stimulation postinjection seismicity thermal effects thermo‐poro‐elasticity

Identify lymphatic metastasis-associated genes in mouse hepatocarcinoma cell lines using gene chip

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World Journal of Gastroenterology 2005年第10期11卷 1463-1472页

作者： BoSong Jian-WuTang BoWang Xiao-NanCui LiHou LuSun Li-MinMao Chun-HuiZhou yuedu Li-HuiWang Hua-XinWang Ren-ShuZheng LeiSun DepartmentofPathology DalianMedicalUniversityDalian116027LiaoningProvinceChina ShanghaiJingtaiBiotechnologyCorporationLtd Shanghai200000China

AIM: In order to obtain lymphogenous metastasisassociated genes, we compared the transcriptional profiles of mouse hepatocarcinoma cell lines Hca-F with highly lymphatic metastasis potential and Hca-P with low lymphatic metastasis ***: Total RNA was isolated from Hca-F and Hca-P cells and synthesized into double-stranded cDNA. In vitro transcription double-stranded cDNA was labeled with biotin (i.e. biotin-labeled cRNA, used as the probe). The cRNA probes hybridized with Affymetrix GeneChip() MOE430A (containing 22 690 transcripts, including 14 500 known mouse genes and 4 371 ESTs) respectively and the signals were scanned by the GeneArray Scanner. The results were then analyzed by ***: Out of the 14 500 known genes investigated,110 (0.8%) were up regulated at least 23 fold. Among the total 4 371 ESTs, 17 ESTs (0.4%) (data were not presented) were up regulated at least 23 fold. According to the Gene Ontology and TreeView analysis, the 110genes were further classified into two groups: differential biological process profile and molecular function ***: Using high-throughput gene chip method,a large number of genes and their cellular functions about angiogenesis, cell adhesion, signal transduction, cell motility, transport, microtubule-based process, cytoskeleton organization and biogenesis, cell cycle, transcription,chaperone activity, motor activity, protein kinase activity,receptor binding and protein binding might be involved in the process of lymphatic metastasis and deserve to be used as potential candidates for further *** D1, Fosl1, Hsp47, EGFR and AR, and Cav-1 are selected as the possible candidate genes of the metastatic phenotype, which need to be validated in later *** (data were not presented) might indicate novel genes associated with lymphatic metastasis. Validating the function of these genes is helpful to identify the key or candidate gene/pathway responsible for lymphatic m

关键词： Hepatocarcinoma Lymphatic metastasis Cell lines Hca-F and Hca-P Gene chip

超临界CO_(2)作用下煤体结构面剪切硬化特征与本构模型

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煤炭学报 2023年第12期48卷 4487-4498页

作者：韦婕陈跃都梁卫国太原理工大学矿业工程学院山西太原030024 太原理工大学原位改性采矿教育部重点实验室山西太原030024

在深部煤层(> 800 m) CO_(2)地质封存过程中,受高温高压作用影响,CO_(2)常以超临界态存在。受非均匀地应力及注入流体压力作用下,煤层中发育的大量节理、裂隙等结构面会发生剪切滑移,进而影响煤体力学性能并增加CO_(2)泄露风险。因此,... 详细信息

在深部煤层(> 800 m) CO_(2)地质封存过程中,受高温高压作用影响,CO_(2)常以超临界态存在。受非均匀地应力及注入流体压力作用下,煤层中发育的大量节理、裂隙等结构面会发生剪切滑移,进而影响煤体力学性能并增加CO_(2)泄露风险。因此,揭示超临界CO_(2)长期作用下煤体结构面剪切力学特性,是保证封存安全性的关键。通过开展超临界CO_(2)不同浸泡时间后的煤体结构面直剪力学试验,结果表明:(1)随着超临界CO_(2)作用时间增加,煤体结构面剪切强度和剪切刚度均逐渐减小;超临界CO_(2)浸泡14 d后,煤体结构面剪切强度和剪切刚度分别降低40%和28%。(2)超临界CO_(2)作用时间增加会导致煤体结构面剪胀变形减小,剪缩效应明显,同时造成结构面微凸体破碎体积增加;超临界CO_(2)浸泡14 d后,煤体结构面破碎体积量增加至未浸泡的1.5倍。(3)煤体结构面剪切过程中剪应力与声发射参数之间存在着很强的相关性,振铃计数在峰值应力处增至最大;随着超临界CO_(2)作用时间增加,声发射累计振铃计数、累计撞击数与累计能量等参数均逐渐减小,煤体结构面脆性破裂特征减弱,塑性增强。(4)未浸泡煤体结构面呈现出明显剪切软化特征,而超临界CO_(2)作用后煤体结构面剪切向硬化特征转变,通过建立一种新的结构面剪切本构模型,能够很好表征上述转变特征,且模型理论值与试验值有较高拟合程度。

关键词： CO_(2)地质封存超临界CO_(2) 煤体结构面剪切硬化

从运动链的角度看by在有标记被动结构中的句法功能

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鸡西大学学报（综合版） 2012年第12期12卷 59-61页

作者：曾跃都电子科技大学中山学院外国语学院广东中山528403

依据认知语法有关运动链的理论,探讨by-短语在有标被动结构中同运动链发生何种关系,从而指出,by的语义取决于同运动链的特殊关系。与相关介词with、from、through相比,by之所以具有更广的语用适应性以及更强的句法功能,皆因其唤起施事... 详细信息

依据认知语法有关运动链的理论,探讨by-短语在有标被动结构中同运动链发生何种关系,从而指出,by的语义取决于同运动链的特殊关系。与相关介词with、from、through相比,by之所以具有更广的语用适应性以及更强的句法功能,皆因其唤起施事的固有性质。

关键词：运动链有标记被动结构原型