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Cohesive Harmony Analysis: Measuring the Coherence of a Text

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Annual Review of Functional Linguistics

Annual Review of Functional Linguistics 2015年 56-70+176页

作者： tian jianqiu Peking University

This paper probes into Cohesive Harmony Analysis(CHA) as a measure of the coherence of a text. It first traces its origin to Hasan’s research on the degree of coherence in texts produced by 6 to 7 years old children from different social backgrounds. Following that, the paper introduces several basic concepts, including cohesive tie, cohesive device, cohesive chain, chain interaction and cohesive harmony. Following a discussion of the analytical procedure, it describes the applications of CHA in language teaching, linguistic pathology and identity and identification analysis. The paper ends with a conclusion and a brief discussion of the possible future development of CHA.

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Effects of Inter-Particle Frictional Coefficients on Evolution of Contact Networks in Landslide Process

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Engineering（科研） 2017年第11期9卷 917-936页

作者： Lian Jiang Enlong Liu jianqiu tian Xiaoqiong Jiang State Key Laboratory of Hydraulics and Natural River Engineering College of Water Resource and Hydropower Sichuan University Chengdu China Northwest Institute of Eco-Environment and Resources State Key Laboratory of Frozen Soil Engineering CAS Lanzhou China

During the process of landslide, its dynamic mechanism is important to understand and predict these kinds of natural hazard. In this paper, a new method, based on concepts of complex networks, has been proposed to investigate the evolution of contact networks in mesoscale during the sliding process of slope. A slope model was established using the discrete element method (DEM), and influences of inter-particle frictional coefficients with four different values on?dynamic landslides were studied. Both macroscopic analysis on slope?landslide?and mesoanalysis on structure evolution of contact networks, including the?average degree, clustering coefficient?and N-cycle, were done during the process?of landslide. The analysis results demonstrate that: 1) with increasing inter-particle?frictional coefficients, the displacement of slope decreases and the stable angle of slope post-failure increases, which is smaller than the peak internal frictional angle;2) the average degree decreases with the increase of inter-particle frictional coefficient. When the displacement at the toe of the slope is smaller,?the average degree there changes more greatly with increasing inter-particle?frictional coefficient;3) during the initial stage of landslide, the clustering coefficient?reduces sharply, which may leads to easily slide of slope. As the landslide?going?on, however, the clustering coefficient?increases denoting increasing stability?with?increasing inter-particle frictional coefficients. When the inter-particle?frictional coefficient is smaller than 0.3, its variation can affect the clustering coefficient?and stable inclination of slope post-failure greatly;and 4) the number of?3-cycle increases, but 4-cycle and 5-cycle decrease with increasing inter-particle frictional coefficients.

关键词： Evolution of Contact Network Landslide Complex Network Inter-Particle Frictional Clustering Coefficient N-Cycle

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多国/地区生命末期医疗指示语类研究

外语研究 2021年第4期38卷 31-37页

作者：田剪秋北京大学外国语学院北京100871

生命末期医疗指示,又称预先医疗指示,是决策者在意识清醒时表达对临终阶段维持生命治疗和代理决策者偏好的文件。本研究采用语类作为意义生成中介的语境模型,考察世界各主要国家/地区生命末期医疗指示的语类成分及语篇整体结构。分析表... 详细信息

生命末期医疗指示,又称预先医疗指示,是决策者在意识清醒时表达对临终阶段维持生命治疗和代理决策者偏好的文件。本研究采用语类作为意义生成中介的语境模型,考察世界各主要国家/地区生命末期医疗指示的语类成分及语篇整体结构。分析表明,各国家/地区生命末期医疗指示的整体语类结构相似,但也依法律法规和文化习俗有所不同。此语类可以作为宏观语类的一个部分,还可以构成语类集合和语类系统,共同完成临终和身后事项的实践。

关键词：生命末期医疗指示语类作为意义生成中介的语境模型语类分析语篇语义分析语类系统和语类集合

生态、对话和分布式视域及虚拟环境与第二语言学习的互构

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中国外语 2020年第3期17卷 36-44页

作者：郑东萍田剪秋夏威夷大学二语研究系北京大学外国语学院

自2009年以来,来自夏威夷大学的郑东萍和她的合作者应用生态心理学(特别是可供性)理论、社会文化理论、分布式语言理论和对话主义等理论,在虚拟空间中开展第二语言研究和教育。她们在这些理论的指导下,设计和开发虚拟环境和学习活动,同... 详细信息

自2009年以来,来自夏威夷大学的郑东萍和她的合作者应用生态心理学(特别是可供性)理论、社会文化理论、分布式语言理论和对话主义等理论,在虚拟空间中开展第二语言研究和教育。她们在这些理论的指导下,设计和开发虚拟环境和学习活动,同时也扩展和发展了这些理论。这种基于设计的研究范式在语言学习及其参与者、语境、物质环境和技术特征中互构出新的概念,例如,行动协商、关爱语言学习行动、生态-对话跨言语学习和多层协同言语学习。在这种研究中,研究问题基于过程数据,由此也产生出新的研究方法。这种观点关注言语行动过程,使研究人员能够看到整体事件,即语言学习是在生态、心理和文化活动中涌现出的结果。这种由理论驱动的学习环境和技术适应过程的融合设计,为第二/外语学习和研究提供了新的可能性。

关键词：分布式语言可供性虚拟世界技术学习环境协同/协作

A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things

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Computers, Materials & Continua 2024年第1期78卷 1297-1310页

作者： Hongliang tian Junyuan tian College of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data *** address these issues,a blockchain-based IoT reputation value attribute access control scheme is ***,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control *** simulation experiments based on the Hyperledger Fabric *** simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices.

关键词： Blockchain IoT access control Hyperledger Fabric

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis *** this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture ***,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model *** comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)

CCL9/CCR1 axis-driven chemotactic nanovesicles for attenuating metastasis of SMAD4-deficient colorectal cancer by trapping TGF-β

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3711-3729页

作者： Boning Niu tianyi tian Lu Wang Yinmei tian tian tian Yuanyuan Guo Hu Zhou Zhiping Zhang Tongji School of Pharmacy Huazhong University of Science and TechnologyWuhan 430030China Department of Oncology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Pharmacy Liyuan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China School of Pharmaceutical Sciences Fujian Provincial Key Laboratory of Innovative Drug Target ResearchHigh Throughput Drug Screening PlatformXiamen UniversityXiamen 361102China National Engineering Research Center for Nanomedicine Huazhong University of Science and TechnologyWuhan 430030China Hubei Engineering Research Centre for Novel Drug Delivery System Huazhong University of Science and TechnologyWuhan 430030China

SMAD4 deficiency in colorectal cancer(CRC)is highly correlated with liver metastasis and high mortality,yet there are few effective precision therapies ***,we show that CCR1^(+)-granulocytic myeloid-derived suppressor cells(G-MDSCs)are highly infiltrated in SMAD4-deficient CRC via CCL15/CCR1 and CCL9/CCR1 axis in clinical specimens and mouse models,*** excessive TGF-β,secreted by tumor-infiltrated CCR1^(+)-G-MDSCs,suppresses the immune response of cytotoxic T lymphocytes(CTLs),thus facilitating ***,we develop engineered nanovesicles displaying CCR1 and TGFBR2 molecules(C/T-NVs)to chemotactically target the tumor driven by CCL9/CCR1 axis and trap TGF-βthrough TGF-β-TGFBR2 specific *** C/T-NVs counteract CCR1^(+)-G-MDSC infiltration through competitive responding CCL9/CCR1 axis.C/T-NVs-induced intratumoral TGF-βexhaustion alleviates the TGF-β-suppressed immune response of ***,C/T-NVs attenuate liver metastasis of SMAD4-deficient *** further exploration,high expression of programmed cell death ligand-1(PD-L1)is observed in clinical specimens of SMAD4-deficient *** C/T-NVs with anti-PD-L1 antibody(aPD-L1)induces tertiary lymphoid structure formation with sustained activation of CTLs,CXCL13^(+)-CD4^(+)T,CXCR5^(+)-CD20^(+)B cells,and enhanced secretion of cytotoxic cytokine interleukin-21 and IFN-γaround tumors,thus eradicating metastatic *** strategy elicits pleiotropic antimetastatic immunity,paving the way for nanovesicle-mediated precision immunotherapy in SMAD4-deficient CRC.

关键词： SMAD4-deficient CRC Metastasis G-MDSCs TGF-β CCR1 TGFBR2

Capturing metal clusters at the strong-interaction region to reverse Ostwald ripening

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Science China Materials 2024年第4期67卷 1363-1364页

作者： Shuheng tian Ding Ma Beijing National Laboratory for Molecular Sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

High-temperature interactions induce sintering of metal nanoparticles(NPs) on heterogeneous catalyst surfaces, leading to reduced surface area and active site loss through Ostwald ripening [1]. This irreversible deactivation necessitates costly catalyst replacement, notably impacting metals like copper in hydrogenation and reforming reactions [2].

关键词： catalyst reforming irreversible