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Chinese Geographical Science 2022年第1期32卷 49-63页

作者： MA Li KANG Lei tian huazheng XU Die Institute of Geographic Sciences and Nature Resources Research Chinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Chinese Academy of SciencesBeijing 100101.China College of Resources ancl Environment University of Chinese Academy of SciencesBeijing 100049China

Although the development of energy and mineral resources strongly supports China’s rapid industrialization and urbanization,it has led to a series of ecological and environmental *** the spatial regulation considering the ecological and environmental protection on energy and mineral resource development areas is an important aspect of realizing China’s sustainable *** this study,we mapped,categorized,and analyzed the ecological cumulative effects of the Chinese 134 prefectural mining units based on the pressure-state-response model,which is demonstrated as impact of mining activities on ecological environment,ecological environmental fragility,and ecological *** investigation developed a stress zoning typology of the mining units based on scores of three dimensions of the ecological cumulative effects and classified 134 prefectural mining units into eight types of stress zones.A series of regulation and policy suggestions have been proposed to different types of zones from three aspects:space control,intensity control,and development mode *** application of this evaluation and spatial zoning system will contribute to the refined spatial management of China’s mining areas.

关键词： ecological cumulative effects quantitative evaluation pressure-state-response model zoning

黄河流域矿产资源开发的生态环境影响与空间管控路径

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资源科学 2020年第1期42卷 137-149页

作者：马丽田华征康蕾中国科学院地理科学与资源研究所区域可持续发展分析与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100049

黄河流域作为中国的"能源流域",合理有序开发矿产资源、统筹协调矿产资源开发与生态环境保护之间的关系,对于黄河流域能矿经济可持续发展和生态保护具有重要现实意义。本文以黄河流域为研究区,综合运用多指标综合评价法、胁迫耦合分析法... 详细信息

黄河流域作为中国的"能源流域",合理有序开发矿产资源、统筹协调矿产资源开发与生态环境保护之间的关系,对于黄河流域能矿经济可持续发展和生态保护具有重要现实意义。本文以黄河流域为研究区,综合运用多指标综合评价法、胁迫耦合分析法和GIS空间分析等方法技术,从生态本底的脆弱程度、对重要生态功能区的空间胁迫性以及对重要生态环境因子的胁迫程度等多个层面,分析了区域矿产资源开发对生态环境的胁迫特征及空间分布,将黄河流域46个矿区城市划分为本底胁迫、生态功能胁迫、开发胁迫、本底+开发胁迫、开发+生态功能胁迫、本底+生态功能胁迫、全面胁迫和无胁迫8种不同类型区,并从生态环境保护的角度提出黄河流域矿产资源开发地区的管控路径:①空间管控:严格限制大规模高强度工业化城镇化开发,尤其是控制矿区的开发边界;②强度管控:针对于生态本底脆弱的地区,强度和总体开发规模的管控要兼而并举;③开发方式管控:注重能矿产业的结构调整与升级,在空间上要注重集中建设,宜矿则矿、宜工则工、宜聚则聚。

关键词：矿产资源开发生态环境影响胁迫空间管控黄河流域

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东北三省全面振兴的社会经济支撑能力评估

地理科学 2020年第6期40卷 863-873页

作者：马丽田华征康蕾戚伟中国科学院区域可持续发展分析与模拟重点实验室/中国科学院地理科学与资源研究所北京100101 中国科学院大学资源与环境学院北京100049

在解析支撑能力和东北问题特点的基础上,从"创新、协调、绿色、开放、共享"五大理念出发建立全面振兴社会经济支撑能力评价指标体系和综合评价方法,以地级市为单元对东北三省进行评估。研究发现:各地市社会经济支撑能力差异显著,哈大沿... 详细信息

在解析支撑能力和东北问题特点的基础上,从"创新、协调、绿色、开放、共享"五大理念出发建立全面振兴社会经济支撑能力评价指标体系和综合评价方法,以地级市为单元对东北三省进行评估。研究发现:各地市社会经济支撑能力差异显著,哈大沿线核心城市的支撑能力较强,西翼城市以及朝阳、七台河、绥化、葫芦岛、铁岭、双鸭山和鹤岗等资源型城市支撑能力较弱。因此未来东北地区在振兴政策的区域分布上应有所侧重,对不同地区施以不同的振兴或扶持政策。在创新、绿色、开放方面需要集中力量重点突破,而在体制机制改革和共享服务建设方面需要全面覆盖,并重点加强黑龙江北部和辽宁、吉林西翼城市的共享能力建设。

关键词：东北三省社会经济支撑能力定量评估指标体系

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

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)

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

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

DeepSI:A Sensitive-Driven Testing Samples Generation Method of Whitebox CNN Model for Edge Computing

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Tsinghua Science and Technology 2024年第3期29卷 784-794页

作者： Zhichao Lian Fengjun tian School of Cyber Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

In recent years,Deep Learning(DL)technique has been widely used in Internet of Things(IoT)and Industrial Internet of Things(IIoT)for edge computing,and achieved good *** more and more studies have shown the vulnerability of neural ***,it is important to test the robustness and vulnerability of neural *** specifically,inspired by layer-wise relevance propagation and neural network verification,we propose a novel measurement of sensitive neurons and important neurons,and propose a novel neuron coverage criterion for robustness *** on the novel criterion,we design a novel testing sample generation method,named DeepSI,which involves definitions of sensitive neurons and important ***,we construct sensitive-decision paths of the neural network through selecting sensitive neurons and important ***,we verify our idea by setting up several experiments,then results show our proposed method achieves superior performances.

关键词： neuron sensitivity Layer-wise Relevance Propagation(LRP) neural network verification deeplearning testing

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG Long ZHAO tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage