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隐藏访问策略的高效CP-ABE方案

计算机研究与发展 2019年第10期56卷 2151-2159页

作者：王悦樊凯西安文理学院信息工程学院西安710065 西安电子科技大学网络与信息安全学院西安710071

人工智能的发展离不开云计算的支撑,同样,人工智能的安全与云上大数据的安全也是密切相关的.目前,基于密文策略的属性基加密(ciphertext policy attribute-based encryption,CP-ABE)被认为是实现云上数据细粒度访问控制最有效的方法之一... 详细信息

人工智能的发展离不开云计算的支撑,同样,人工智能的安全与云上大数据的安全也是密切相关的.目前,基于密文策略的属性基加密(ciphertext policy attribute-based encryption,CP-ABE)被认为是实现云上数据细粒度访问控制最有效的方法之一.在基于密文策略属性基加密方案中,访问策略与密文相关且绑定,但很多时候,访问策略本身就是敏感信息,若以明文形式存放在云端会造成用户数据的泄露.因此,一种隐藏访问策略的高效CP-ABE方案被提出以解决这一问题.它可以使得属性隐藏和秘密共享能够同时应用到“与”门结构中,然后利用合数阶双线性群构造了一种基于包含正负及无关值的“与门”的策略隐藏方案,该方案有效地避免了用户的具体属性值泄露给其他第三方,确保了用户隐私的安全.此外,通过实验验证及分析,保证了该方案在实现复杂访问结构的策略隐藏的同时,还满足解密时间短,解密效率高的优点.

关键词：大数据安全属性加密访问结构策略隐藏访问控制

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核岛设计采购进度研究

核动力工程 2006年第2期27卷 91-96页

作者：范凯徐顺中国广东核电工程有限公司广东深圳518124

用网络图的形式归纳了核岛设计采购基本逻辑框图,阐述了设计采购计划编排的基本依据和思路,按系统设计、施工设计及设备采购分类,给出了典型进度逻辑图,并分别对进度编排方案作了详细分析。

关键词：核岛设计采购进度控制

物联网中超轻量级RFID电子票据安全认证方案

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计算机研究与发展 2018年第7期55卷 1432-1439页

作者：王悦樊凯西安文理学院信息工程学院西安710065 西安电子科技大学网络与信息安全学院西安710071

随着物联网应用技术的日益普及,作为其中重要技术之一的无线射频识别(radio frequency identification,RFID)技术在各个领域的应用场景越来越丰富.电子票据将RFID技术应用于传统票证,使得传统票证具备可存储、可识别、可验证等特性,在... 详细信息

随着物联网应用技术的日益普及,作为其中重要技术之一的无线射频识别(radio frequency identification,RFID)技术在各个领域的应用场景越来越丰富.电子票据将RFID技术应用于传统票证,使得传统票证具备可存储、可识别、可验证等特性,在很大程度上给人们的日常出行带来了巨大的便捷和高效.尽管如此,RFID系统在电子票证上的应用仍然面临着许多安全风险,比如隐私泄露.针对RFID技术在电子票据应用中存在的安全问题,提出了一种超轻量级的安全高效的认证方案.和一些采用复杂加密运算的方案相比,该方案采用简单的逻辑运算和时间戳同步升级机制,可有效抵抗失同步攻击和重放攻击,并可有效防止信息泄露.同时,该方案在数据库中采用时间戳匹配标签信息的方法,极大地提高了数据搜索效率.经过对安全性和高效性方面的分析以及对性能的仿真比较,可知所提方案相比现有方案在安全性和效率上均有较大提升.

关键词：无线射频识别安全认证超轻量级电子票据物联网

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行星探测进入多卫星任务时代

科学通报 2021年第34期66卷 4350-4353页

作者：范开魏勇中国科学院地质与地球物理研究所北京100029

2021年2月,我国自主研发的首颗火星探测器"天问一号"在飞行6个余月、跨越4.65亿千米后,成功进入火星环绕轨道."天问一号"为单颗卫星环火配合火星车着陆的联合探测模式,其主要科学任务包括调查火星浅表面、大气和空间环境,进而理解火星... 详细信息

2021年2月,我国自主研发的首颗火星探测器"天问一号"在飞行6个余月、跨越4.65亿千米后,成功进入火星环绕轨道."天问一号"为单颗卫星环火配合火星车着陆的联合探测模式,其主要科学任务包括调查火星浅表面、大气和空间环境,进而理解火星水、冰和大气演化历史[1,2]."天问一号"将作为我国行星探测计划的"开门红",为我国后续太阳系行星探测任务揭开序幕.

关键词：大气演化行星探测火星探测器天问火星车探测模式自主研发

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Tea polyphenols dominate the short-term tea(Camellia sinensis) leaf litter decomposition

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第2期18卷 99-108页

作者： Dong-mei fan kai fan Cui-ping YU Ya-ting LU Xiao-chang WANG Institute of Tea Science College of Agriculture and Biotechnology Zhejiang University Hangzhou 310058 China Research Institute of Agricultural Sciences Wuzhou 543002 China

Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography（HPLC） and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid（GA）, catechin gallate（CG）, and gallocatechin（GC） were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols.

关键词： Tea polyphenol Catechin Decomposition Nutrient release Polyphenol/N ratio

Construction of CuO-modified zeolitic imidazolate framework-9 for photocatalytic hydrogen evolution

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Chinese Journal of Catalysis 2017年第12期38卷 2056-2066页

作者： kai fan Zhiliang Jin Hong Yuan Hongyan Hu Yingpu Bi School of Chemistry and Chemical Engineering North Minzu University Yinchuan 750021 Ningxia China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000Gansu China

An efficient CuO‐modified zeolitic imidazolate framework‐9(ZIF‐9)photocatalyst is successfully prepared at room temperature under mild *** is observed that the ZIF‐9/CuO photocatalyst is effective for H2generation under visible light with sacrificial agent *** the CuO is introduced,the photocatalytic properties of ZIF‐9are greatly improved and when the content of CuO is40%,the photocatalytic activity reaches a maximum of78.74μmol *** results from the200–300nm cube structure of ZIF‐9being able to adsorb more dye molecules and the CuO,which connects with ZIF‐9,greatly improving the electronic transmission ***,the interaction between the dye molecule Eosin Y(EY)and the catalyst is also studied by transient fluorescence spectroscopy.A series of characterizations,such as SEM,TEM,XPS,XRD,UV‐vis,FTIR,transient fluorescence and photocurrent,are conducted,and the results are in good agreement with the experimental *** addition,the possible reaction mechanism over EY‐sensitized ZIF‐9/CuO under visible light irradiation is proposed.

关键词： ZIF‐9 CuO Eosin Y Sensitized pathway Hydrogen evolution Reaction optimization

Risk factors and predictive model of adrenocortical insuffi ciency in patients with traumatic brain injury

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World Journal of Emergency Medicine 2021年第3期12卷 179-184页

作者： Gui-long Feng Miao-miao Zheng Shi-hong Yao Yin-qi Li Shao-jun Zhang Wei-jing Wen kai fan Jia-li Zhang Xiao Zhang Department of Emergency the First Hospital of Shanxi Medical UniversityTaiyuan 030001China Department of Emergency Zhenjiang First People’s HospitalZhenjiang 212000China Department of Emergency Yuncheng Central HospitalYuncheng 044500China Department of Endocrinology the Fourth Affi liated HospitalZhejiang University School of MedicineYiwu 322000China

BACKGROUND:Neuroendocrine dysfunction after traumatic brain injury(TBI)has received increased attention due to its impact on the recovery of neural *** purpose of this study is to investigate the incidence and risk factors of adrenocortical insuffi ciency(AI)after TBI to reveal independent predictors and build a prediction model of AI after ***:Enrolled patients were grouped into the AI and non-AI *** preset impact factors were *** were regrouped according to each impact factor as a categorical *** and multiple logistic regression analyses were performed to screen the related independent risk factors of AI after TBI and develop the predictive ***:A total of 108 patients were recruited,of whom 34(31.5%)patients had *** factors(age,Glasgow Coma Scale[GCS]score on admission,mean arterial pressure[MAP],urinary volume,serum sodium level,cerebral hernia,frontal lobe contusion,diff use axonal injury[DAI],and skull base fracture)were probably related to AI after *** factors(urinary volume[X4],serum sodium level[X5],and DAI[X8])were independent variables,based on which a prediction model was developed(logit P=-3.552+2.583X4+2.235X5+2.269X8).CONCLUSIONS:The incidence of AI after TBI is *** such as age,GCS score,MAP,urinary volume,serum sodium level,cerebral hernia,frontal lobe contusion,DAI,and skull base fracture are probably related to AI after *** volume,serum sodium level,and DAI are the independent predictors of AI after TBI.

关键词： Adrenocortical insuffi ciency Risk factor Predictor Traumatic brain injury

Prospective evaluation of heparin-induced thrombocytopenia expert probability and 4T scores in Chinese patients with suspected heparin-induced thrombocytopenia

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Chinese Medical Journal 2019年第12期132卷 1441-1447页

作者： Sen Li Lian-kai fan Shu-Jie Wang Yong-Qiang Zhao Department of Hematology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730. China Department of Clinical Laboratory Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Background: Diagnosis of heparin-induced thrombocytopenia (HIT) is challenging. This study aimed to compare the diagnostic performance of HIT expert probability (HEP) and 4T scores, and to evaluate the inter-observer reliability for the 4T score in a clinical setting. Methods: This prospective study included HIT-suspected patients between 2016 and 2018. Three hematologists assessed the HEP and 4T scores. Correlations between scores and anti-platelet factor 4 (anti-PF4)/heparin antibodies were evaluated. Receiver operating characteristic curves and area under the curve (AUC) were used to assess the predictive accuracy of these two scoring models. The intraclass correlation coefficient (ICC) was used to assess the inter-observer agreement of 4T scores between residents and hematologists. Results: Of the 89 subjects included, 22 (24.7%) were positive for anti-PF4/heparin antibody. The correlations between antibody titer and either HEP or 4T scores were similar (r = 0.392, P < 0.01 for the HEP score;r = 0.444, P < 0.01 for the 4T score). No significant difference in the diagnostic performance was displayed between these two scores (AUC for the HEP score: 0.778 vs. AUC for the 4T score: 0.741, P = 0.357). Only 72 4T scores were collected from the residents, with a surprisingly low percentage of observers (43.1%) presenting the four individual item scores which made up their 4T score. The AUC of 4T score assessed by residents and hematologists was 0.657 (95% confidence interval [CI]: 536–0.765) and 0.780 (95% CI: 0.667–0.869, P < 0.05), respectively. The ICC of 4T score between residents and hematologists was 0.49 (95% CI: 0.29–0.65, P < 0.01), demonstrating a fair inter-observer agreement. Conclusions: The HEP score does not display a better performance for predicting HIT than the 4T score. With the unsatisfactory completion rate, the inter-observer agreement of 4T score in a tertiary hospital is fair, underscoring the necessity for continuing education for physicians.

关键词： Heparin-induced thrombocytopenia Clinical scoring model 4T score HIT expert probability score

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带流体动力学阻尼的IBq方程的精确解

东北大学学报（自然科学版） 2017年第10期38卷 1516-1520页

作者：宋叔尼范凯东北大学理学院辽宁沈阳110819 太原科技大学应用科学学院山西太原030024

对带流体动力学阻尼的IBq方程进行了研究,发现虽然对Bq方程精确解的研究很多,但对IBq方程解的研究结果却很少.介绍了求解非线性演化方程的Tanh法与扩展Tanh函数法,使用符号计算软件Maple和Tanh函数法获得带流体动力学阻尼的IBq方程的大... 详细信息

对带流体动力学阻尼的IBq方程进行了研究,发现虽然对Bq方程精确解的研究很多,但对IBq方程解的研究结果却很少.介绍了求解非线性演化方程的Tanh法与扩展Tanh函数法,使用符号计算软件Maple和Tanh函数法获得带流体动力学阻尼的IBq方程的大量双曲函数精确解,主要为扭结和反扭结孤立子解.对精确解中未知参数进行赋值,图解表示了部分精确解,这对于数值解的准确性和稳定性的核对是有用的.获得的结果证实该方法用于分析求解数学物理中各种非线性偏微分方程是有效的.

关键词： Tanh函数法扩展Tanh函数法双曲函数精确解 IBq方程流体动力学阻尼