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Fast Marching Method for Microseismic Source Location in Cavern-Containing Rockmass: Performance Analysis and Engineering Application

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Engineering 2021年第7期7卷 1023-1034页

作者： Ruochen Jiang Feng Dai Yi Liu Ang Li State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China School of Highway Chang’an UniversityXi’an 710064China

Microseismic(MS)event locations are vital aspect of MS monitoring technology used to delineate the damage zone inside the surrounding rock mass.However,complex geological conditions can impose significantly adverse effects on the final location results.To achieve a high-accuracy location in a complex cavern-containing structure,this study develops an MS location method using the fast marching method(FMM)with a second-order difference approach(FMM2).Based on the established velocity model with three-dimensional(3D)discrete grids,the realization of the MS location can be achieved by searching the minimum residual between the theoretical and actual first arrival times.Moreover,based on the calculation results of FMM2,the propagation paths from the MS sources to MS sensors can be obtained using the linear interpolation approach and the Runge–Kutta method.These methods were validated through a series of numerical experiments.In addition,our proposed method was applied to locate the recorded blasting and MS events that occurred during the excavation period of the underground caverns at the Houziyan hydropower station.The location results of the blasting activities show that our method can effectively reduce the location error compared with the results based on the uniform velocity model.Furthermore,the obtained MS location was verified through the occurrence of shotcrete fractures and spalling,and the monitoring results of the in-situ multipoint extensometer.Our proposed method can offer a more accurate rock fracture location and facilitate the delineation of damage zones inside the surrounding rock mass.

关键词： Fast marching method Microseismic event location Cavern-containing complex rock mass Runge-Kutta method

Investigation of the influence of intermediate principal stress on the dynamic responses of rocks subjected to true triaxial stress state

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International Journal of Mining Science and Technology 2021年第5期31卷 913-926页

作者： Wei You Feng Dai Yi Liu Hongbo Du Ruochen Jiang State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China

Precisely understanding the dynamic mechanical properties and failure modes of rocks subjected to true triaxial stress state(σ1>σ2>σ3,whereσ1,σ2,andσ3 are the major principal stress,intermediate principal stress,and minor principal stress,respectively)is essential to the safety of underground engineering.However,in the laboratory,it is difficult to maintain the constant true triaxial stress state of rocks during the dynamic testing process.Herein,a numerical servo triaxial Hopkinson bar(NSTHB)was developed to study the dynamic responses of rocks confronted with a true triaxial stress state,in which lateral stresses can maintain constant.The results indicate that the dynamic strength and elastic modulus of rocks increase with the rise of intermediate principal stressσ2,while the dynamic elastic modulus is independent of the dynamic strain rate.Simulated acoustic emission distributions indicate that the intermediate principal stressσ2 dramatically affects dynamic failure modes of triaxial confined rocks.Asσ2 increases,the failure pattern switches from a single diagonal shear zone into two parallel shear zones with a small slant.Moreover,a recent triaxial Hopkinson bar experimental system using three bar pairs is also numerically established,and the measuring discrepancies are identified between the two numerical bar systems.The proposed NSTHB system provides a controllable tool for studying the dynamic triaxial behavior of rocks.

关键词： Triaxial Hopkinson bar Intermediate principal stress Dynamic strength Failure modes Numerical simulation True triaxial stress

SpinNet: Spinning convolutional network for lane boundary detection

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Computational Visual Media 2019年第4期5卷 417-428页

作者： ruochen Fan Xuanrun Wang Qibin Hou Hanchao Liu Tai-jiang Mu Tsinghua University Beijing100084China Nankai University Tianjin300350China

In this paper,we propose a simple but effective framework for lane boundary detection,called Spin Net.Considering that cars or pedestrians often occlude lane boundaries and that the local features of lane boundaries are not distinctive,therefore,analyzing and collecting global context information is crucial for lane boundary detection.To this end,we design a novel spinning convolution layer and a brand-new lane parameterization branch in our network to detect lane boundaries from a global perspective.To extract features in narrow strip-shaped fields,we adopt stripshaped convolutions with kernels which have 1×n or n×1 shape in the spinning convolution layer.To tackle the problem of that straight strip-shaped convolutions are only able to extract features in vertical or horizontal directions,we introduce the concept of feature map rotation to allow the convolutions to be applied in multiple directions so that more information can be collected concerning a whole lane boundary.Moreover,unlike most existing lane boundary detectors,which extract lane boundaries from segmentation masks,our lane boundary parameterization branch predicts a curve expression for the lane boundary for each pixel in the output feature map.And the network utilizes this information to predict the weights of the curve,to better form the final lane boundaries.Our framework is easy to implement and end-to-end trainable.Experiments show that our proposed Spin Net outperforms state-of-the-art methods.

关键词： object detection lane boundary detection autonomous driving deep learning

消费情景、感知质量对产品溢价的影响——基于自动售货机业态的实证研究

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北京工商大学学报（社会科学版） 2020年第6期35卷 15-27页

作者：高振江若尘上海商学院工商管理学院上海201400 上海财经大学商学院上海200070

以自动售货机为代表的智能零售已成为一种重要的新型零售业态,推动着中国零售市场迈向智能零售变革时代。利用2019年的问卷调查数据,测量了自动售货机的消费情景、消费者感知质量和产品溢价支付意愿。在此基础上,运用Tobit模型分析发现... 详细信息

以自动售货机为代表的智能零售已成为一种重要的新型零售业态,推动着中国零售市场迈向智能零售变革时代。利用2019年的问卷调查数据,测量了自动售货机的消费情景、消费者感知质量和产品溢价支付意愿。在此基础上,运用Tobit模型分析发现,消费情景直接影响自动售货机的产品溢价,并通过感知质量的中介作用间接影响自动售货机的产品溢价;同时运用层次回归法分析发现,消费者健康意识水平显著负向影响产品溢价,但对感知质量的中介效应的调节作用并不明显。因而,从多方面打造自动售货机消费情景,例如优化自动售货机选址决策、增加健康产品比例、增强消费情景的社交性等,是提高消费者感知质量和自动售货机产品溢价的关键。

关键词：消费情景感知质量健康意识产品溢价自动售货机

善因营销的捐赠水平与消费者态度:一个有中介的调节效应模型检验

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心理学报 2017年第5期49卷 692-698页

作者：江若尘郑玲上海财经大学国际工商管理学院上海财经大学上海发展研究院上海200433

通过两个实验,探讨了善因营销的捐赠水平对消费者态度的影响,尤其是考察了道德提升感的中介作用以及产品-公益事业拟合度的调节作用。研究发现,善因营销的捐赠水平对消费者态度有显著的正向影响,且道德提升感在捐赠水平与消费者态度之... 详细信息

通过两个实验,探讨了善因营销的捐赠水平对消费者态度的影响,尤其是考察了道德提升感的中介作用以及产品-公益事业拟合度的调节作用。研究发现,善因营销的捐赠水平对消费者态度有显著的正向影响,且道德提升感在捐赠水平与消费者态度之间起中介作用。与此同时,产品-公益事业拟合度显著地调节了捐赠水平与道德提升感的关系,且该调节关系通过道德提升感的中介作用来进一步影响消费者态度。

关键词：善因营销捐赠水平道德提升感消费者态度产品-公益事业拟合度

企业资源、交易成本与跨国公司国际市场进入模式选择

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财贸研究 2018年第8期29卷 49-61页

作者：高振江若尘上海商学院管理学院上海201400 上海财经大学500强企业研究中心上海200433

采用跨国公司海外机构的组织模式数据为样本,利用Logit模型检验企业资源条件(企业规模、国际化经验、业务多元化)和市场交易成本因素(交易环境不确定性、交易行为不确定性、交易频率)对国际市场进入模式选择的影响效应。结果显示,企业... 详细信息

采用跨国公司海外机构的组织模式数据为样本,利用Logit模型检验企业资源条件(企业规模、国际化经验、业务多元化)和市场交易成本因素(交易环境不确定性、交易行为不确定性、交易频率)对国际市场进入模式选择的影响效应。结果显示,企业规模越大以及国际化经验越丰富,市场交易频率越高,企业选择股权模式的概率越大;实施多元化战略以及市场交易环境和交易行为不确定性越大的情况下,企业选择非股权模式的概率越大。此外,采用多种建模方法检验了样本自相关和自选择问题,结果表明这两个问题对模型结论均没有产生显著影响。

关键词：企业资源交易成本跨国公司国际市场进入模式

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旅游体验价值共创研究最新进展及管理启示

管理现代化 2019年第1期39卷 74-77页

作者：匡红云江若尘上海第二工业大学高职学院上海201209 上海财经大学商学院上海200434 上海财经大学500强企业研究中心上海200433

服务主导逻辑下价值共创是市场经济得以实现的核心环节,而价值共创则需借助于互动和体验。旅游业是典型的体验产业,基于国内外最新研究现状,通过对旅游体验价值共创的定义内涵、影响因素和生成结果等成果的梳理,总结出促进旅游体验价值... 详细信息

服务主导逻辑下价值共创是市场经济得以实现的核心环节,而价值共创则需借助于互动和体验。旅游业是典型的体验产业,基于国内外最新研究现状,通过对旅游体验价值共创的定义内涵、影响因素和生成结果等成果的梳理,总结出促进旅游体验价值共创的实践方式,为价值共创理论研究和旅游企业管理实践提供借鉴。

关键词：旅游体验价值共创影响因素影响结果

S4Net: Single stage salient-instance segmentation

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Computational Visual Media 2020年第2期6卷 191-204页

作者： ruochen Fan Ming-Ming Cheng Qibin Hou Tai-jiang Mu Jingdong Wang Shi-Min Hu BNRist Tsinghua UniversityBeijing100086China Nankai University Tianjin300071China MSRA Beijing100086China

In this paper, we consider salient instance segmentation. As well as producing bounding boxes,our network also outputs high-quality instance-level segments as initial selections to indicate the regions of interest. Taking into account the category-independent property of each target, we design a single stage salient instance segmentation framework, with a novel segmentation branch. Our new branch regards not only local context inside each detection window but also the surrounding context, enabling us to distinguish instances in the same scope even with partial occlusion.Our network is end-to-end trainable and is fast(running at 40 fps for images with resolution 320 × 320). We evaluate our approach on a publicly available benchmark and show that it outperforms alternative solutions. We also provide a thorough analysis of our design choices to help readers better understand the function of each part of our network. Source code can be found at https://***/ruochen Fan/S4 Net.

关键词： salient-instance segmentation salient object detection single stage region-of-interest masking

我国信贷关系网络宏观拓扑特征及系统性信贷风险鉴别

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财贸经济 2014年第11期35卷 55-66页

作者：江若尘陆煊上海财经大学上海发展研究院上海财经大学国际工商管理学院

本文运用复杂网络技术,构建我国金融机构-企业信贷关系网络及其映射子网络。研究表明,我国金融机构-企业信贷关系网络存在典型的无标度网络特性。本文发现,在同一信贷关系网络中,同时存在异配性和"富者俱乐部"特征,使信贷关系网络的节... 详细信息

本文运用复杂网络技术,构建我国金融机构-企业信贷关系网络及其映射子网络。研究表明,我国金融机构-企业信贷关系网络存在典型的无标度网络特性。本文发现,在同一信贷关系网络中,同时存在异配性和"富者俱乐部"特征,使信贷关系网络的节点连结模式呈现出"核-边缘"格局,表明大型金融机构、大型企业主导了我国信贷资源,竞争优势明显,小型金融机构和中小企业竞争力较弱。通过最小生成树分析,揭示了信贷网络层级模块化特征,还发现各层级、簇集、子群的顶点是信贷风险管控的关键实体。本文提出了一种新的系统重要性节点鉴别指标——信贷风险指数,并建议对高风险指数实体采取差异化风险管控策略。本研究对政策引导,优化监管资源配置,增强我国信贷系统稳健性具有一定的参考意义。

关键词：信贷关系网络宏观拓扑特征无标度网络 “核-边缘”模式信贷风险指数