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Blockzone: A Decentralized and Trustworthy Data Plane for DNS

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Computers, Materials & Continua 2020年第11期65卷 1531-1557页

作者： Ning hu Shi yin Shen Su Xudong Jia qiao Xiang Hao Liu Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhouChina Department of Computer Science Yale UniversityNew Haven06520-8241USA Qianxin Technology Group Co. Ltd.BeijingChina

The domain name system(DNS)provides a mapping service between memorable names and numerical internet protocol addresses,and it is a critical infrastructure of the Internet.The authenticity of DNS resolution results is crucial for ensuring the accessibility of Internet services.hundreds of supplementary specifications of protocols have been proposed to compensate for the security flaws of DNS.However,DNS security incidents still occur frequently.Although DNS is a distributed system,for a specified domain name,only authorized authoritative servers can resolve it.Other servers must obtain the resolution result through a recursive or iterative resolving procedure,which renders DNS vulnerable to various attacks,such as DNS cache poisoning and distributed denial of service(DDoS)attacks.This paper proposes a novel decentralized architecture for a DNS data plane,which is called Blockzone.First,Blockzone utilizes novel mechanisms,which include on-chain authorization and off-chain storage,to implement a decentralized and trustworthy DNS data plane.Second,in contrast to the hierarchical authentication and recursive query of traditional DNS,Blockzone implements a decentralized operation model.This model significantly increases the efficiency of domain name resolution and verification and enhances the security of DNS against DDoS and cache poisoning attacks.In addition,Blockzone is fully compatible with the traditional DNS implementation and can be incrementally deployed as a plug-in service of DNS without changing the DNS protocol or system architecture.The Blockzone scheme can also be generalized to address security issues in other areas,such as the Internet of things and edge computing.

关键词： Network security DNS security DNS decentralization blockchain

Impact of insect-resistant GM rice on pesticide use and farmers' health in China

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Science China(Life Sciences) 2015年第5期58卷 466-471页

作者： huANG JiKun hu RuiFa qiao FangBin yin YanHong LIU huaiJu huANG ZhuRong Center for Chinese Agricultural Policy Institute of Geographical Sciences and Natural Resource Research Chinese Academy of Sciences School of Management and Economics Beijing Institute of Technology China Economics and Management Academy Central University of Finance and Economics Department of Neurology Chinese PLA General Hospital

The economic benefits of insect-resistant genetically modified(GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss.

关键词：转基因水稻发展中国家抗虫转基因农药使用农民健康电解质体系经济利益

Microstructure failure in ferrite-martensite dual phase steel under in-situ tensile test

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Journal of Iron and Steel Research(International) 2017年第3期24卷 350-356页

作者： Rui-bin Gou Wen-jiao Dan Wei-gang Zhang Min Yu Chun-yu Zhang Yin-hu qiao Lu Ma Department of Engineering Mechanics Shanghai Jiao Tong University Shanghai 200240 China School of Mechanical Engineering Anhui Science and Technology University Bengbu 233100 Anhui China Innovation Center for Advanced Ship and Deep Sea Exploration Shanghai Jiao Tong University Shanghai 200240 China College of Architecture Anhui Science and Technology University Bengbu 233100 Anhui China

To investigate microstructure failure in ferrite-martensite dual phase steel,in-situ observations were performed on multiple plate DP800 specimens during uniaxial tensile tests. Microstructure evolution of the observed region was investigated in details. The experimental data showed that micro-cracks in various regions differed in the initiation time,and micro-failures mainly occurred from the locations with typical characteristics of stress concentration（ i. e. ferrite interiors,the interfaces of ferrite-martensite grains and the martensite-martensite interfaces）. Growth of micro-crack generally experienced the following stages： cracking from martensite boundaries,tiny particles in ferrite interiors,or martensite interiors,propagating in ferrite,bypassing martensite boundaries,or passing through martensite-martensite interfaces,finally ending on martensite boundaries. Martensite was one important source of micro-failure and changed the propagation of micro-cracks significantly. Microstructure deformation was inhomogeneous in the stage of plastic deformation.

关键词： Micro-fracture Dual phase steel Ferrite Martensite In-situ observation

Ample dietary fat reduced the risk of primary vesical calculi by inducing macrophages to engulf budding crystals in mice

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Acta Pharmaceutica Sinica B 2022年第2期12卷 747-758页

作者： huiling Chen Kaiqiang hu Yaru Liang Yuqi Gao Chenye Zeng Kang Xu Xiaojin Shi Liyuan Li Yuemiao yin Yi qiao ying Qiu Qingfei Liu Zhao Wang School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China Urology Department Peking Union Medical College HospitalBeijing 100730China School of Medicine Tsinghua UniversityBeijing 100084China

Although primary vesical calculi is an ancient disease,the mechanism of calculi formation remains unclear.In this study,we established a novel primary vesical calculi model with D,L-choline tartrate in mice.Compared with commonly used melamine and ethylene glycol models,our model was the only approach that induced vesical calculi without causing kidney injury.Previous studies suggest that proteins in the daily diet are the main contributors to the prevention of vesical calculi,yet the effect of fat is overlooked.To assay the relationship of dietary fat with the formation of primary vesical calculi,D,L-choline tartrate-treated mice were fed a high-fat,low-fat,or normal-fat diet.Genetic changes in the mouse bladder were detected with transcriptome analysis.A high-fat diet remarkably reduced the morbidity of primary vesical calculi.Higher fatty acid levels in serum and urine were observed in the high-fat diet group,and more intact epithelia in bladder were observed in the same group compared with the normal-and low-fat diet groups,suggesting the protective effect of fatty acids on bladder epithelia to maintain its normal histological structure.Transcriptome analysis revealed that the macrophage differentiation-related gene C-X-C motif chemokine ligand 14(Cxcl14)was upregulated in the bladders of high-fat diet-fed mice compared with those of normal-or low-fat diet-fed mice,which was consistent with histological observations.The expression of CXCL14 significantly increased in the bladder in the high-fat diet group.CXCL14 enhanced the recruitment of macrophages to the crystal nucleus and induced the transformation of M2 macrophages,which led to phagocytosis of budding crystals and prevented accumulation of calculi.In human bladder epithelia(HCV-29)cells,high fatty acid supplementation significantly increased the expression of CXCL14.Dietary fat is essential for the maintenance of physiological functions of the bladder and for the prevention of primary vesical calculi,which provides new ideas for the reduction of morbid

关键词： Primary vesical calculi Diet High-fat D,L-Choline tartrate Macrophage CXCL14 Fatty acid Urothelium

Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

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Nano-Micro Letters 2024年第7期16卷 281-294页

作者： Yu-ying Shi Si-Yuan Liao qiao-Feng Wang Xin-Yun Xu Xiao-Yun Wang Xin-yin Gu You-Gen hu Peng-Li Zhu Rong Sun Yan-Jun Wan Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Southern University of Science and Technology Shenzhen 518055People’s Republic of China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

关键词： EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition Flexibility

The TripleSat constellation:a new geospatial data service model

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Geo-Spatial Information Science 2017年第2期20卷 163-173页

作者： Qiang Wen Jianjun He Shengyong Guan Ting Chen yin hu Wenbin Wu Feng Liu Yuexia qiao Suet Yheng Kok Samuel Yeong 21st Century Aerospace Technology Co. Ltd.BeijingChina 21st Century Aerospace Technology(Asia)Pte.Ltd. Singapore

With the increase of different sensors,applications and customers,the demand from data providers and users is for a new geospatial data service model,which supports low cost,high dexterity,and which would provide a comprehensive service.Based on such requirements and demands,the 21AT TripleSat constellation terminal and data delivery and management system has been developed by a Beijing based high-tech enterprise,Twenty First Century Aerospace Technology Co.,Ltd.(21AT).The company is the first commercial Earth observation satellite operator and service provider in China.This new geospatial data service model allows the user to directly access multi-source satellite data,manage the data order,and carry out automatic massive data production and delivery.The solution also implements safe and hierarchical user management,statistical data analysis,and automatic information reports.In addition,a mobile application is also available for users to easily access system functions.This new geospatial solution has already been successfully applied and installed in many customer sites in China,and is now available globally for international clients interested in fast geospatial solutions.It enables the success of customers’operational services.Besides providing TripleSat Constellation images,the multi-source data access system also allows the users to access other satellite data sources,based on customized agreement.This paper describes and discusses this new geospatial data service model.

关键词： Geospatial data service model 21AT TripleSat constellation geospatial instant service system

目标意象约束的人机辅助产品造型进化设计研究

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机械设计 2022年第2期39卷 120-128页

作者：王剑陈丰乔印虎安徽科技学院机械工程学院安徽滁州233100 燕山大学艺术与设计学院河北秦皇岛066004

为实现康复辅具造型求解方案的多样化需求,提出目标意象约束的人机辅助产品造型进化设计方法。构建了意象约束的产品造型进化设计体系与整体流程;从用户角度出发,针对用户意象需求的模糊性和多样化问题,通过三角模糊理论和因子分析法确... 详细信息

为实现康复辅具造型求解方案的多样化需求,提出目标意象约束的人机辅助产品造型进化设计方法。构建了意象约束的产品造型进化设计体系与整体流程;从用户角度出发,针对用户意象需求的模糊性和多样化问题,通过三角模糊理论和因子分析法确定群体目标意象;借助SD量表,采用多元尺度分析、聚类分析等方法确定产品优势样本;根据产品建模特点,运用形态分析法对其造型基因层次进行提取与表达;通过BP神经网络构建预测模型,对目标意象与造型基因间的非线性关系进行映射,基于输出结果建立进化设计目标函数;利用遗传算法的全局寻优能力,将神经网络输出意象评价作为个体适应度评估依据,以样本的解空间为载体进行基因进化,搜索目标造型的优质解。以踝足矫形器(Ankle and Foot Orthosis,AFO)为研究对象,试验结果表明:该优化方法可适用于其造型进化设计,提高了设计效率,为人机辅助性产品的造型改进设计提供参考和借鉴。

关键词：造型进化设计踝足矫形器意象约束 BP神经网络遗传算法

Luminescence property and magnetic resonance imaging of Gd_(2)O_(3):Tb^(3+) nanocrystals doped with Zn^(2+),Li^(+)

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Rare Metals 2021年第8期40卷 2049-2058页

作者： Rong Fu Yan-Yan hu hui-Na qiao Chun-Lin Yang Hao yin Mei-Gui Ou College of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang550025China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang550003China Department of Neurosurgery Guizhou Provincial People’s HospitalGuiyang550002China

Gd_(2)O_(3):Tb^(3+) nanocrystal co-doped with Zn^(2+)and Li^(+) was prepared by the combination of polyol and solid-phase methods.The synthesized nanoparticles were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),photoluminescence(PL)spectra and magnetic resonance imaging(MRI).The results revealed that both Gd_(2)O_(3):Tb^(3+)/Zn^(2+) and Gd_(2)O_(3):Tb^(3+)/Li^(+) had cubic unit structures with a spherical shape,and the fluorescence intensity of the nanoparticles reached a maximum at a doping concentration of0.050 mmol%for Zn^(2+) and 2 mol%for Li^(+),respectively.In addition,the T_(1)/T_(2)(longitudinal/transverse relaxation time)-weighted MRI signals got enhanced due to the increased longitudinal relaxivity(r1)and transverse relaxivity(r2)after the doping by metal ions.Therefore,the materials reported here can be used for fluorescence and MR bimodal imaging,as tracers and for fluorescence detections.

关键词： Gd_(2)O_(3):Tb^(3+) Zn^(2+)/Li^(+)doping Luminescent property Magnetic resonance imaging Nanomaterials

Study of the numerical simulation of tight sandstone gas molecular diffusion based on digital core technology

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Petroleum Science 2018年第1期15卷 68-76页

作者： Hong-Lin Zhu Shou-Feng Wang Guo-Jun yin qiao Chen Feng-Lin Xu Wei Peng Yan-hu Tan Kuo Zhang Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Oil and Gas Engineering Research Institute Jilin Oilfield Company PetroChina Shu’nan Gas Mine Southwest Oil and Gas Field Branch Company PetroChina Co. Ltd

Diffusion is an important mass transfer mode of tight sandstone gas. Since nano-pores are extensively developed in the interior of tight sandstone, a considerable body of research indicates that the type of diffusion is mainly molecular diffusion based on Fick＇s law. However, accurate modeling and understanding the physics of gas transport phenomena in nanoporous media is still a challenge for researchers and traditional investigation（analytical and experimental methods） have many limitations in studying the generic behavior. In this paper, we used Nano-CT to observe the pore structures of samples of the tight sandstone of western of Sichuan. Combined with advanced image processing technology, threedimensional distributions of the nanometer-sized pores were reconstructed and a tight sandstone digital core model was built, as well the pore structure parameters were analyzed quantitatively. Based on the digital core model, the diffusion process of methane molecules from a higher concentration area to a lower concentration area was simulated by a finite volume method. Finally, the reservoir＇s concentration evolution was visualized and the intrinsic molecular diffusivity tensor which reflects the diffusion capabilities of this rock was calculated. Through comparisons, we found that our calculated result was in good agreement with other empirical results. This study provides a new research method for tight sandstone digital rock physics. It is a foundation for future tight sandstone gas percolation theory and numerical simulation research.

关键词： Tight sandstone gas Nano-CT Digital core Molecular diffusion Numerical simulation