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交通基础设施投资能够促进农村产业融合吗?——来自中国土地市场的证据

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产经评论 2024年第3期15卷 36-50页

作者：郭益蓓张坤鹏河南大学国际商学院

交通基础设施投资是推动经济增长和促进地区经济发展的关键因素,具有减贫效应和促进农业发展的作用,其对农村产业融合发展的影响亟待探讨。通过整理2010—2019年中国土地市场网公布的交通运输用地供地信息,衡量交通基础设施投资力度,并... 详细信息

交通基础设施投资是推动经济增长和促进地区经济发展的关键因素,具有减贫效应和促进农业发展的作用,其对农村产业融合发展的影响亟待探讨。通过整理2010—2019年中国土地市场网公布的交通运输用地供地信息,衡量交通基础设施投资力度,并利用同期中国县级层面的经济数据测算农村产业融合水平,实证检验交通基础设施投资对农村产业融合水平的影响和作用机制。结果显示:各县交通基础设施投资力度的提高会显著提升当地农村产业融合水平。这一影响因经济地理区位、农业功能定位和交通能力定位的不同而存在差异,交通基础设施投资对中西部地区、粮食主产区和交通强国试点区域的农村产业融合具有显著推动作用。进一步的机制分析发现,交通基础设施投资能够打破城乡壁垒,通过提高地区间交通运输能力、促进产业集聚和激发创新活力等途径提升农村产业融合水平。

关键词：交通基础设施投资农村产业融合城乡融合土地市场

基于图Transformer网络的城市路网短时交通流预测模型

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科学技术与工程 2024年第10期24卷 4307-4316页

作者：周烽王世璞张坤鹏河南工业大学电气工程学院郑州450001 清华大学自动化系北京100084

针对城市路网短时交通流预测问题,在考虑路网交通状态时空相关性基础上,提出了一种基于图Transformer(graph transformer,Graformer)的预测方法。该方法将多条路段的交通状态预测问题转化为图节点状态预测问题,针对区分相同结构的空间... 详细信息

针对城市路网短时交通流预测问题,在考虑路网交通状态时空相关性基础上,提出了一种基于图Transformer(graph transformer,Graformer)的预测方法。该方法将多条路段的交通状态预测问题转化为图节点状态预测问题,针对区分相同结构的空间路网结构图,将带有边的图同构网络(graph isomorphism network with edges,GINE)和Transformer网络相结合,对交通状态在路网层面的时空相关性进行建模,从而实现城市路网短时交通流预测。具体来说,Graformer模型首先利用长短期记忆网络(long short-term memory,LSTM)对交通数据的时序信息进行预处理,接着采用基于GINE与Transformer的全局注意力机制提取交通数据的空间特征,最后实现路网各路段交通流的同步预测。

关键词：短时交通流预测图同构网络 Transformer 时空相关性

考虑用户满意度的云制造资源群智能优化决策方法

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制造业自动化 2024年第4期46卷 1-6,11页

作者：张坤鹏王艳纪志成江南大学物联网技术应用教育部工程研究中心无锡214122

针对云制造资源分配中面临的资源配置低效、制造服务选择非最优的问题,提出了考虑用户满意度的云制造资源群智能优化决策方法。对云制造过程分别建立了时间、成本、服务质量及其对应满意度的多目标模型,通过改进粒子群算法对其进行求解... 详细信息

针对云制造资源分配中面临的资源配置低效、制造服务选择非最优的问题,提出了考虑用户满意度的云制造资源群智能优化决策方法。对云制造过程分别建立了时间、成本、服务质量及其对应满意度的多目标模型,通过改进粒子群算法对其进行求解,采用基于主客观赋权法的多准则妥协解决策评价体系选取最优解。为了克服粒子群早熟收敛,融合切比雪夫滤波器和速度二阶振荡改进算法,同时为了反应客观数据的对比强度,客观赋权法引入变异系数。最后仿真阐明,改进算法相对其他算法的解集更广泛,收敛性更好,并验证了模型与决策方法的有效性。

关键词：云制造用户满意度多目标粒子群切比雪夫滤波器主客观赋权

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： kun Gao Yan peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： kun Gao Yan peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Clinicopathologic significance of slug expression in human intrahepatic cholangiocarcinoma

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World Journal of Gastroenterology 2010年第20期16卷 2554-2557页

作者： zhang, Ke-Jun zhang, Bing-Yuan zhang, kun-peng Tang, Li-Min Liu, Shi-Song Zhu, Dong-Ming zhang, Dian-Liang Qingdao Univ Qingdao Med Coll Affiliated Hosp Dept Radiol Qingdao 266003 Shandong Peoples R China Qingdao Univ Qingdao Med Coll Affiliated Hosp Dept Gen Surg 2 Qingdao 266003 Shandong Peoples R China Suzhou Univ Dept Gen Surg Affiliated Hosp 1 Suzhou 215006 Jiangsu Prov Peoples R China

AIM:To explore the expression and function of slug,a transcriptional repressor,in human intrahepatic cholangiocarcinoma(IHCC)and identify its role in IHCC ***:Expression of slug was detected in 36 cases of IHCC and 12 cases of normal intrahepatic bile ducts and liver parenchyma by *** patients were divided into low slug expression group(< 20%of carcinoma cells stained)and high slug expression group(≥20%of carcinoma cells stained).Slug expression was correlated with clinicopathological parameters of IHCC *** patients were defined as short-term survivors if their survival time was<12 mo and as longterm survivors if their survival time was≥12 ***:Slug was not expressed in normal liver epi-thelium samples,lowly expressed in 15 tissue samples (10-,5+)and highly expressed in 21 tissue samples (16++;5+++)from IHCC *** survival rate of patients with a low slug expression was 33.3%(n =5)and 66.7%(n=10),*** survival rate of patients with a high slug expression was 61.9% (n=13)and 38.1%(n=8),respectively(P=0.02).Lymph node metastasis was found in 4(26.7%)out of the 15 patients with a low slug expression and in 14(66.7%)out of the 21 patients with a high slug expression,*** incidence rate of lymph node metastasis increased with the increasing slug expression level(P=0.003),and higher in patients with a high slug expression than in those with a low slug *** expression did not significantly correlate with the tumor size and stage or histologic grade,or with the gender and age of ***:Slug expression is a novel prognostic marker for IHCC with lymph node metastasis.

关键词： Intrahepatic cholangiocarcinoma Transcriptional repressor Slug Clinicopathologic significance

PHLDA2 reshapes the immune microenvironment and induces drug resistance in hepatocellular carcinoma

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Oncology Research 2024年第6期32卷 1063-1078页

作者： kun FENG HAO peng QINGpeng LV YEWEI zhang Hepatopancreatobiliary Center The Second Affiliated Hospital of Nanjing Medical UniversityNanjing210000China Medical School Southeast UniversityNanjing210000China

Hepatocellular carcinoma(HCC)is a malignancy known for its unfavorable *** dysregulation of the tumor microenvironment(TME)can affect the sensitivity to immunotherapy or chemotherapy,leading to treatment *** elucidation of PHLDA2’s involvement in HCC is imperative,and the clinical value of PHLDA2 is also ***,bioinformatics analysis was performed in multiple cohorts to explore the phenotype and mechanism through which PHLDA2 may affect the progression of ***,the expression and function of PHLDA2 were examined via the qRT-PCR,Western Blot,and MTT *** findings indicate a substantial upregulation of PHLDA2 in HCC,correlated with a poorer *** methylation levels of PHLDA2 were found to be lower in HCC tissues compared to normal liver ***,noteworthy associations were observed between PHLDA2 expression and immune infiltration in *** addition,PHLDA2 upregulation is closely associated with stemness features and immunotherapy or chemotherapy resistance in *** vitro experiments showed that sorafenib or cisplatin significantly up-regulated PHLDA2 mRNA levels,and PHLDA2 knockdown markedly decreased the sensitivity of HCC cells to chemotherapy ***,we found that TGF-βinduced the expression of PHLDA2 in *** GSEA and in vitro experiment indicated that PHLDA2 may promote the HCC progression via activating the AKT signaling *** study revealed the novel role of PHLDA2 as an independent prognostic factor,which plays an essential role in TME remodeling and treatment resistance in HCC.

关键词： HCC Immune infiltration Drug resistance TME PHLDA2

Semaphorin 3C (Sema3C) reshapes stromal microenvironment to promote hepatocellular carcinoma progression

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3429-3448页

作者： Hao peng Meng Yang kun Feng Qingpeng Lv Yewei zhang Medical School Southeast UniversityNanjing 210009China Department of Ultrasound State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of MedicalSciencesPeking Union Medical CollegeBeijing 100730China Hepatopancreatobiliary Center The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210009China

More than 90% of hepatocellular carcinoma(HCC)cases develop in the presence of fibrosis or cirrhosis,making the tumor microenvironment(TME)of HCC distinctive due to the intricate interplay between cancer-associated fibroblasts(CAFs)and cancer stem cells(CSCs),which collectively regulate HCC ***,the mechanisms through which CSCs orchestrate the dynamics of the tumor stroma during HCC development remain *** study unveils a significant upregulation of Sema3C in fibrotic liver,HCC tissues,peripheral blood of HCC patients,as well as sorafenib-resistant tissues and cells,with its overexpression correlating with the acquisition of stemness properties in *** further identify NRP1 and ITGB1 as pivotal functional receptors of Sema3C,activating downstream AKT/Gli1/c-Myc signaling pathways to bolster HCC self-renewal and tumor ***,HCCcells-derived Sema3Cfacilitated extracellular matrix(ECM)contraction and collagen deposition in vivo,while also promoting the proliferation and activation of hepatic stellate cells(HSCs).Mechanistically,Sema3C interacted with NRP1 and ITGB1 in HSCs,activating downstream NF-kB signaling,thereby stimulating the release of IL-6 and upregulating HMGCR expression,consequently enhancing cholesterol synthesis in ***,CAF-secreted TGF-β1 activates AP1 signaling to augment Sema3C expression in HCC cells,establishing a positive feedback loop that accelerates HCC ***,blockade of Sema3C effectively inhibits tumor growth and sensitizes HCC cells to sorafenib in *** sum,our findings spotlight Sema3C as a novel biomarker facilitating the crosstalk between CsCs and stroma during hepatocarcinogenesis,thereby offering a promising avenue for enhancing treatment efficacy and overcoming drug resistance in HCC.

关键词： Sema hepatocellular thereby

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

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Petroleum Science 2024年第2期21卷 1171-1189页

作者： kun-peng zhang Mian Chen Chang-Jun Zhao Su Wang Yong-Dong Fan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering in China University of Petroleum Beijing102249China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment ***, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS