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Track dynamic behavior at rail welds at high speed

Acta Mechanica Sinica 2010年第3期26卷 449-465页

作者： Guangwen Xiao Xinbiao Xiao Jun guo Zefeng wen Xuesong jin State Key Laboratory of Traction Power Southwest Jiaotong University 610031 Chengdu China

As a vehicle passing through a track with different weld irregularities, the dynamic performance of track com- ponents is investigated in detail by using a coupled vehi- cle-track model. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom, and a Timoshenko beam is used to model the rails which are dis- cretely supported by sleepers. In the track model, the sleepers are modeled as rigid bodies accounting for their vertical, lat- eral and rolling motions and assumed to move backward at a constant speed to simulate the vehicle running along the track at the same speed. In the study of the coupled vehicle and track dynamics, the Hertizian contact theory and the theory proposed by Shen-Hedrick-Elkins are, respectively, used to calculate normal and creep forces between the wheel and the rails. In the calculation of the normal forces, the coefficient of the normal contact stiffness is determined by transient contact condition of the wheel and rail surface. In the calcu- lation of the creepages, the lateral, roll-over motions of the rail and the fact that the relative velocity between the wheel and rail in their common normal direction is equal to zero are simultaneously taken into account. The motion equations of the vehicle and track are solved by means of an explicit integration method, in which the rail weld irregularities are modeled as local track vertical deviations described by some ideal cosine functions. The effects of the train speed, the axle load, the wavelength and depth of the irregularities, and the weld center position in a sleeper span on the wheel-rail impact loading are analyzed. The numerical results obtained are greatly useful in the tolerance design of welded rail pro- file irregularity caused by hand-grinding after rail welding and track maintenances.

关键词： Rail weld. Irregularity. Vehicle-trackcouplingdynamics

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A new method for fluid identification and saturation calculation of low contrast tight sandstone reservoir

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Petroleum Science 2024年第5期21卷 3189-3201页

作者： Shuai Wang Ran-Hong Xie guo-wen jin Jiang-Feng guo Li-Zhi Xiao State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

The resistivity difference between oil and gas layers and the water layers in low contrast tight sandstone reservoirs is subtle. Fluid identification and saturation calculation based on conventional logging methods are facing challenges in such reservoirs. In this paper, a new method is proposed for fluid identification and saturation calculation in low contrast tight sandstone reservoirs. First, a model for calculating apparent formation water resistivity is constructed, which takes into account the influence of shale on the resistivity calculation and avoids apparent formation water resistivity abnormal *** on the distribution of the apparent formation water resistivity obtained by the new model, the water spectrum is determined for fluid identification in low contrast tight sandstone *** this, according to the average, standard deviation, and endpoints of the water spectrum, a new four-parameter model for calculating reservoir oil and gas saturation is built. The methods proposed in this paper are applied to the low contrast tight sandstone reservoirs in the Q4 formation of the X53 block and X70 block in the south of Songliao Basin, China. The results show that the water spectrum method can effectively distinguish oil-water layers and water layers in the study area. The standard deviation of the water spectrum in the oil-water layer is generally greater than that in the water layer. The new four-parameter model yields more accurate oil and gas saturation. These findings verify the effectiveness of the proposed methods.

关键词： Low contrast reservoirs Fluid identification Saturation calculation Water spectrum method Conventional logging

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Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means

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Petroleum Science 2023年第5期20卷 2747-2758页

作者： Bo-Han Wu Ran-Hong Xie Li-Zhi Xiao Jiang-Feng guo guo-wen jin Jian-Wei Fu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic *** PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as *** unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological *** analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method.

关键词： Tight sandstone Integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means

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Organic matter and concentrated nitrogen removal by shortcut nitrification and denitrification from mature municipal landfill leachate

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Journal of Environmental Sciences 2007年第6期19卷 647-651页

作者： ZHANG Shu-jun PENG Yong-zhen WANG Shu-ying ZHENG Shu-wen guo jin College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^＋-N loading rate （ALR） of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^＋-N/（m^3-d） and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^＋-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^＋-N/（m^3.d）, the NH4^＋-N removal efficiency was more than 98%. With the influent NH4^＋-N of 1200-1800 mg/L, the effluent NH4^＋-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^＋-N was only 2-3, the total inorganic nitrogen （TIN） removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria （AOB） accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria （NOB） accounted only for 0.2% of the total eubaeterial population.

关键词： mature landfill leachate UASB+A/O shortcut nitrification carbon source

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基于图聚类的蛋白质功能预测方法

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福建师范大学学报（自然科学版） 2015年第3期31卷 26-31,38页

作者：郭金文林劼福建师范大学软件学院福建福州350117

利用蛋白质序列的循环关系,采用循环匹配算法对数据进行预处理,得到相关联蛋白质数据集,再利用该数据集构造蛋白质的网络图,在此基础上采用图聚类算法,对待预测的蛋白质相关的各个蛋白聚类,并进行子群分割,对各个子群采用z值进一步计算... 详细信息

利用蛋白质序列的循环关系,采用循环匹配算法对数据进行预处理,得到相关联蛋白质数据集,再利用该数据集构造蛋白质的网络图,在此基础上采用图聚类算法,对待预测的蛋白质相关的各个蛋白聚类,并进行子群分割,对各个子群采用z值进一步计算并得出作为预测结果的蛋白质功能.经实验,该方法与其它最新方法相比较,预测结果的最终衡量指标F1-measure具有明显的提升.

关键词：蛋白质功能预测循环关系图聚类蛋白质域 F1-measure

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CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

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药物注射结合咬合板治疗颞下颌关节紊乱病的临床研究

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口腔医学研究 2015年第3期31卷 287-289,293页

作者：文世生郭雯瑾梅妍甘肃嘉峪关市第一人民医院口腔科甘肃嘉峪关735100 武汉大学口腔医学院

目的:研究透明质酸钠(sodium hyaluronate,SH)关节腔药物注射法结合佩戴稳定咬合板(stable bite plate,SBP)两种方法在治疗颞下颌关节紊乱病(temporomandibular disorders,TMD)中的应用,并对其效果进行评价。方法:观察组18例颞下颌关节... 详细信息

目的:研究透明质酸钠(sodium hyaluronate,SH)关节腔药物注射法结合佩戴稳定咬合板(stable bite plate,SBP)两种方法在治疗颞下颌关节紊乱病(temporomandibular disorders,TMD)中的应用,并对其效果进行评价。方法:观察组18例颞下颌关节紊乱病患者给予两种治疗方法联合使用;对照组18例颞下颌关节紊乱病患者单纯给予SBP治疗。对比分析治疗前后患者颞下颌关节开口指数(Temporomandibular opening index TOI)、疼痛指数(Visual analog scale VAS)及肌肉压痛指数(PI)和关节压诊分值(JP)的变化。结果:治疗后两组患者的OTI、VAS、PI及JP指数比较,观察组明显低于对照组,有显著性差异(P<0.05)。结论:SH关节腔内注射联合SBP治疗TMD的疗效优于单纯采用SBP治疗。

关键词：颞下颌关节紊乱病稳定咬合板透明质酸钠

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枯草杆菌二联活菌颗粒联合六味安消胶囊治疗肠易激综合征疗效观察

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内蒙古医学杂志 2015年第9期47卷 1040-1042页

作者：郭晋文呼和浩特市第一医院内蒙古呼和浩特010010

目的观察枯草杆菌二联活菌颗粒联合六味安消胶囊治疗肠易激综合征疗效观察临床疗效。方法选取符合罗马Ⅲ标准的肠易激综合征患者148例随机分为观察组和对照组各74例,比较两组患者的治疗效果。结果观察组疗效明显优于对照组(P<0.01)。观... 详细信息

目的观察枯草杆菌二联活菌颗粒联合六味安消胶囊治疗肠易激综合征疗效观察临床疗效。方法选取符合罗马Ⅲ标准的肠易激综合征患者148例随机分为观察组和对照组各74例,比较两组患者的治疗效果。结果观察组疗效明显优于对照组(P<0.01)。观察组74例中,显效者41例,有效者30例,无效者3例;对照组74例中,显效者26例,有效者33例,无效者15例。两组患者在治疗过程中均未发现明显不良反应。结论文中观察组患者采用枯草杆菌二联活菌颗粒联合六味安消胶囊较对照组治疗效果理想,值得临床推广使用。

关键词：肠易激综合征枯草杆菌二联活菌颗粒治疗

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