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基于区块链的健康链系统设计与实现

计算机与数字工程 2020年第12期48卷 2888-2894页

作者：雷志伟李加福张桂刚赵旭张勇邢春晓清华大学行业可信区块链应用技术联合研究中心北京100084 中国科学院自动化研究所北京100190 清华大学信息国家研究中心计算机系互联网产业研究院北京100084

新冠疫情在全球范围肆虐,公共场合中的体温测量和行踪登记是控制疫情蔓延的关键手段,目前的信息记录主要依赖人工纸张录入的方式。纸张录入的方式不仅效率低下,而且还面临着易损易丢失的存档风险,同时难以对过往人员与行踪进行快速筛查... 详细信息

新冠疫情在全球范围肆虐,公共场合中的体温测量和行踪登记是控制疫情蔓延的关键手段,目前的信息记录主要依赖人工纸张录入的方式。纸张录入的方式不仅效率低下,而且还面临着易损易丢失的存档风险,同时难以对过往人员与行踪进行快速筛查。该系统基于微信小程序的开发框架,实现了扫码快速注册以及信息登记的功能,同时基于区块链技术来实现底层数据存储和优化,保证数据的不可篡改和快速溯源,最后通过Nginx服务器进行数据通信。

关键词：比特币区块链微信小程序健康链 Nginx

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异种透明塑料焊接机理及焊缝特征研究

云南化工 2024年第3期51卷 56-60页

作者：张杰李永岗王桂刚青岛爱尔家佳新材料股份有限公司山东青岛266000

以低熔点镁锌合金(MZA)粉末为激光吸收剂,实现聚芳砜(PASF)和聚碳酸酯(PC)的焊接。使用Trace Pro软件追踪了激光与MZA粉末相互作用过程,扫描电镜(SEM)与焊缝元素分析(XPS)探究异种透明塑料焊接机理,最后探究了粉末粒径、粉末层宽度和厚... 详细信息

以低熔点镁锌合金(MZA)粉末为激光吸收剂,实现聚芳砜(PASF)和聚碳酸酯(PC)的焊接。使用Trace Pro软件追踪了激光与MZA粉末相互作用过程,扫描电镜(SEM)与焊缝元素分析(XPS)探究异种透明塑料焊接机理,最后探究了粉末粒径、粉末层宽度和厚度对焊接强度及焊缝特征的影响。结果表明:激光与MZA粉末相互作用过程为复合反射行为,并沿着金属颗粒的间隙向前传播;焊接接头是由“钉扎”结构和化学键合共同组成的;在MZA粉末粒径为48μm、粉末层宽度为3 mm、粉末层厚度为0.08 mm的条件下,PASF/PC焊接件具有最优的焊接效果。

关键词：异种透明塑料金属粉末焊接机理射线追踪

High adaptability of Pinus sylvestris *** to drought-induced soil nutrient deficiency

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Ecological Processes 2022年第1期11卷 512-524页

作者： Jingling zhang guigang Lin Qiong Zhao De‑Hui Zeng CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Daqinggou Ecological Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China School of Resources and Environmental Engineering Anhui UniversityHefei 230601China

Background:Drought can exert a profound influence on soil nutrient availability,and understanding whether and how tree species adapt to this change is a critical priority for predicting the consequence of climate change on forest structure and *** objective of this study was to examine the adaptability of Mongolian pine(Pinus sylvestris ***)to drought‑induced changes in soil nutrient availability from the perspective of root ***:We conducted a 7‑year precipitation manipulation experiment with three levels of throughfall reduction(0%,30%,and 50%)to simulate different drought *** measured soil physicochemical properties and fineroot nutrient concentrations and biomass,and calculated the stoichiometric homeostatic regulation coefficient(1/H)of fine ***:Drought reduced soil organic carbon(C),nitrogen(N),phosphorous(P)and inorganic N concentrations,as well as ratios of total N to total P,and available N to available P in the 0–20 cm soil *** contrast,drought had no significant effect on fine‑root N and P concentrations,and fine‑root biomass in the 0–40 cm soil *** roots displayed high homeostatic regulation coefficients of N(with 1/H values of 0.19 and 0)and P(with 1/H values of 0.33 and 0)concentrations in 0–20 and 20–40 cm soil layers,***:Our results indicate that drought leads to soil nutrient deficiency and the decoupling between N and P cycling,and provide evidence that Mongolian pine has high adaptability to drought‑induced decrease in soil nutrient availability by maintaining great fine‑root biomass to ensure sufficient nutrient uptake.

关键词： C:N:P stoichiometry Fine‑root biomass Stoichiometric homeostasis Throughfall reduction

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智能合约的分段同态加密研究

计算机与数字工程 2020年第12期48卷 2932-2937页

作者：王沛然李加福雷志伟张桂刚张勇邢春晓清华大学行业可信区块链应用技术联合研究中心计算机系信息技术研究院北京100084 中国科学院自动化研究所北京100190 清华大学北京信息科学与技术国家研究中心计算机系信息技术研究院互联网产业研究院北京100084

之所以要研究智能合约的加密方案,就是为了让区块链网络中的其他节点在不知晓合约调用参数的前提下,同样可以验证合约执行结果的正确性。纵观整个密码学领域,同态加密是最有希望实现智能合约加密的技术方向。然而,图灵完备的智能合约,... 详细信息

之所以要研究智能合约的加密方案,就是为了让区块链网络中的其他节点在不知晓合约调用参数的前提下,同样可以验证合约执行结果的正确性。纵观整个密码学领域,同态加密是最有希望实现智能合约加密的技术方向。然而,图灵完备的智能合约,其复杂程度与同态加密的技术难度和技术发展速度是一对难以调和的矛盾。所以,选择对智能合约进行切分,并分段使用同态加密技术。完全同态加密方案已经在2009年诞生,并在过去10年里发展并演变出几种主流方案,可以很好地支持智能合约中的算数运算。所以将切入点选在智能合约的判断-分支指令中,从而分段使用全同态加密技术。

关键词：智能合约同态加密指令集编译区块链

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一种全方位监管的区块链系统设计与实现

计算机与数字工程 2023年第1期51卷 81-85,92页

作者：毛湘科李超郝潆婷张桂刚蔚欣张健邢春晓清华大学信息国家研究中心北京100084 清华大学计算机系北京100084 清华大学互联网产业研究院北京100084 中国科学院自动化研究所北京100190

可信交易是现代服务业的核心和基础。金融科技、数字资产交易和电子支付等行业都在尝试采用区块链技术来实现交易的可信性。区块链作为账本具有防篡改、可追溯和透明性等优势,但区块链的匿名性和去中心化的特点又在试图逃避监管。采用... 详细信息

可信交易是现代服务业的核心和基础。金融科技、数字资产交易和电子支付等行业都在尝试采用区块链技术来实现交易的可信性。区块链作为账本具有防篡改、可追溯和透明性等优势,但区块链的匿名性和去中心化的特点又在试图逃避监管。采用区块链实现可信交易离不开对区块链的监管。为使区块链技术能够更好地运用于可信交易,设计了一种新型的区块链对参与者和交易进行监管,同时在出现错误交易和发现不符合监管条件的交易时,能够进行交易回滚,同时设计了事后监管功能对交易进行分析,能够对区块链的交易状况进行监测。最后,采用数据资产交易为例对所设计的区块链系统进行阐述。

关键词：区块链全方位监管可信交易

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区块链数据湖架构研究

计算机与数字工程 2023年第1期51卷 86-92页

作者：张桂刚李超毛湘科郝潆婷李雯晴张健蔚欣邢春晓清华大学信息国家研究中心北京100084 清华大学计算机系北京100084 清华大学互联网产业研究院北京100084 中国科学院自动化研究所北京100190

随着区块链的应用越来越多,成千上万的交易区块链如何实现互联互通,如何实现AML、KYC等分析挖掘越来越成为制约未来区块链发展的障碍。论文研究一种区块链数据湖架构,通过该架构成千上万的区块链会汇聚成区块链数据湖,通过区块链数据湖... 详细信息

随着区块链的应用越来越多,成千上万的交易区块链如何实现互联互通,如何实现AML、KYC等分析挖掘越来越成为制约未来区块链发展的障碍。论文研究一种区块链数据湖架构,通过该架构成千上万的区块链会汇聚成区块链数据湖,通过区块链数据湖不仅实现成千上万的区块链本身的共享,也实现区块链数据以及区块链的各种原始数据的共享,从而为未来全量区块链大数据的分析提供了一种可行的架构和机制。

关键词：区块链数据湖可信交易架构

Heavy haze pollution during the COVID-19 lockdown in the Beijing-Tianjin-Hebei region,China

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Journal of Environmental Sciences 2022年第4期34卷 170-178页

作者： Xin zhang Zhongzhi zhang Zhisheng Xiao guigang Tang Hong Li Rui Gao Xu Dao Yeyao Wang Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China China National Environmental Monitoring Centre Beijing 100012China

To investigate the characteristics of particulate matter with an aerodynamic diameter less than 2.5μm(PM_(2.5))and its chemical compositions in the Beijing-Tianjin-Hebei(BTH)region of China during the novel coronavirus disease(COVID-19)lockdown,the ground-based data of PM_(2.5),trace gases,water-soluble inorganic ions,and organic and elemental carbon were analyzed in three typical cities(Beijing,Tianjin,and Baoding)in the BTH region of China from 5-15 February *** PM_(2.5)source apportionment was established by combining the weather research and forecasting model and comprehensive air quality model with extensions(WRF-CAMx).The results showed that the maximum daily PM_(2.5)concentration reached the heavy pollution level(>150μg/m^(3))in the above three *** sum concentration of SO_(4)^(2-),NO_(3)^(-)and NH_(4)^(+)played a dominant position in PM_(2.5)chemical compositions of Beijing,Tianjin,and Baoding;secondary transformation of gaseous pollutants contributed significantly to PM_(2.5)generation,and the secondary transformation was enhanced as the increased PM_(2.5)*** results of WRF-CAMx showed obviously inter-transport of PM_(2.5)in the BTH region;the contribution of transportation source decreased significantly than previous reports in Beijing,Tianjin,and Baoding during the COVID-19 lockdown;but the contribution of industrial and residential emission sources increased significantly with the increase of PM_(2.5)concentration,and industry emission sources contributed the most to PM_(2.5)***,control policies should be devoted to reducing industrial emissions and regional joint control strategies to mitigate haze pollution.

关键词： COVID-19 lockdown Heavy haze pollution Chemical compositions Source apportionment Beijing-Tianjin-Hebei region

首发未服药精神分裂症患者血清核心蛋白多糖水平与认知功能的关系

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中华行为医学与脑科学杂志 2018年第8期27卷 744-748页

作者：玄燕陈松安会梅王志仁杨甫德谭淑平杨贵刚张向阳周东丰谭云龙北京大学回龙观临床医学院精神科北京100096 北京大学第六医院北京大学精神卫生研究所精神科北京100096

目的通过分析首发未服药精神分裂症患者血清核心蛋白多糖（Decorin,DCN）水平与认知损伤的关系,探讨DCN在精神分裂症发病机制中可能的作用.方法纳入首发未服药的精神分裂症患者30例（精神分裂症组）;同期纳入年龄、性别与疾病组匹配... 详细信息

目的通过分析首发未服药精神分裂症患者血清核心蛋白多糖（Decorin,DCN）水平与认知损伤的关系,探讨DCN在精神分裂症发病机制中可能的作用.方法纳入首发未服药的精神分裂症患者30例（精神分裂症组）;同期纳入年龄、性别与疾病组匹配的健康对照30名（对照组）.采用阳性和阴性症状量表（PANSS）评估精神分裂症组的精神病理症状,MATRICS共识认知成套测验（MCCB）评估所有研究对象的认知功能;采用酶联免疫吸附法（ELISA）检测所有被试的血清DCN水平.结果精神分裂症组血清DCN水平显著低于对照组[（1.56± 0.96） ng/ml,（3.35± 1.71） ng/ml,P＜0.01];血清DCN水平与PANSS阳性症状评分呈正相关（r=0.41,P=0.03）,与MCCB言语流畅度（r=-0.40,P=0.04）、言语记忆（r=-0.42,P=0.02）、视觉记忆（r=-0.39,P=0.04）、持续操作（r=-0.41,P=0.03）、符号编码（r=-0.49,P=0.01）、连线T分（r=-0.42,P=0.02）及总分（r=-0.55,P＜0.01）呈负相关;控制年龄、性别和受教育程度后,上述相关关系仍然存在.结论首发未服药精神分裂症患者血清DCN水平与认知功能相关;DCN可能参与了精神分裂症疾病的发生.

关键词：精神分裂症核心蛋白多糖认知功能

Ultramicrostructure and clinical implications of satellite foci in front of the head of pterygium

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Frontiers of Medicine 2007年第2期1卷 211-214页

作者： LIU Haixia XIANG Nan ZHOU Xiongwu HU Weikun LI guigang zhang Hong The Department of Ophthalmology Tongji HospitalHuazhong University of Science and TechnologyWuhan 430030China

In our previous studies,grey satellite foci were found in the front of heads of *** research was designed to investigate the ultramicrostructure and clinical implications of these satellite *** satellite foci were observed and counted under slit lamp *** patients with eye pterygia were divided into groups in terms of occupation,sex,age,length of history,grade of congestion,and size of the *** SPSS 13.0 software was used for statistical *** cap areas and satellite foci were ultramicrostructurally *** the total 62 eyes with pterygium,satellite foci were found in *** overall incidence of satellite foci was 54.8%.There were no significant differences in incidence among the subjects of different sex,age,and length of *** were significant differences in incidence among the patients of different occupation,grades of congestion,and size of *** grades of congestion,outdoor occupations and larger pterygium heads were associated with higher incidence of satellite *** grades of congestion and bigger heads were also correlated with the number of satellite *** of history bore no correlation with number of satellite ***,the components of the cap areas and the foci were identical,with both consisting of mass of active *** activated fibroblasts existed in the natural tissue planes between Bowman’s layer and basal cell *** fibroblasts in the satellite foci and the cap areas of a pterygium show some features of tumor cells and may play a vital role in the development and progression of a *** presence and amount of satellite foci around a pterygium can be used as an indicator for the speed of its growth.

关键词： pterygium ultramicrostructure fibroblast