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Decentralized Attribute-Based Encryption and Data Sharing Scheme in Cloud Storage

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China Communications 2018年第2期15卷 138-152页

作者： Xiehua Li yanlong Wang Ming xu Yaping Cui College of Computer Science and Electronic Engineering Hunan University

In this paper, we consider the problems of data sharing between multiple distrusted authorities. Prior solutions rely on trusted third parties such as CAs, or are susceptible to collusion between malicious authorities, which can comprise the security of honest ones. In this paper, we propose a new multi-authority data sharing scheme - Decen- tralized Multi-Authority ABE （DMA）, which is derived from CP-ABE that is resilient to these types of misbehavior. Our system distin- guishes between a data owner （DO） principal and attribute authorities （AAs）： the DO owns the data but allows AAs to arbitrate access by providing attribute labels to users. The data is protected by policy encryption over these attributes. Unlike prior systems, attributes generated by AAs are not user-specific, and neither is the system susceptible to collusion between users who try to escalate their access by sharing keys. We prove our scherne correct under the Decisional Bilinear Diffie-Hellman （DBDH） assumption; we also include a com- plete end-to-end implementation that demon- strates the practical efficacy of our technique.

关键词： multi-authority ABE cloud stor-age access policy

Recent Advances in Closed Loop Spray Cooling and its Application in Airborne Systems

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Journal of Thermal Science 2021年第1期30卷 32-50页

作者： xu Xinjie WANG Yu JIANG yanlong LIU Jinxiang YUAN Xiaolei College of Urban Construction Nanjing Tech UniversityNanjing 210009China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In recent years,the problem of heat dissipation in airborne directed energy weapons has attracted considerable research *** cooling can be applied to cool airborne directed energy weapons,owing to its several advantages such as a large heat transfer coefficient,absence of boiling hysteresis and uniform surface *** examine the potential of an airborne spray cooling system,the typical high heat flux dissipation methods were compared,and the state of the art research on spray cooling was *** review was focused on studies related to the spray cooling hydrodynamic mechanism,experimental studies of closed loop spray cooling,numerical simulation studies about spray cooling and the identification of the factors influencing spray cooling systems,and investigations related to the multiple nozzle spray cooling technology and heat transfer correlation ***,there is a need for further research to investigate the failure phenomenon after the critical state,matching operation of the total system and microscopic characteristics of airborne specific parameters.

关键词： spray cooling closed loop heat transfer performance influencing factor correlations

Effects of wind guide plates on wind velocity acceleration and dune leveling： a case study in Ulan Buh Desert, China

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Journal of Arid Land 2017年第5期9卷 743-752页

作者： HAN yanlong GAO Yong MENG Zhongju DANG Xiaohong JIA xu DING yanlong LI Peng College of Desert Control Science and Engineering Inner Mongolia Agricultural University Huhhot 010018 China

The areas used to be covered by shifting sand dunes have been reclaimed rapidly in recent years. However, it is a challenge to reclaim high sand dunes because it is rather costly to level the high dunes to gentle arable lands. In this study, a wind guide plate was used to change the characteristics of natural wind to level the sand dunes. The use of wind energy could significantly increase the efficiency of dune leveling and decrease the cost. Low wind velocity is a typical characteristic in Ulan Buh Desert of China where the average wind speed is much lower than the threshold velocity for sand movement. The experiment of this study was conducted to accelerate the wind velocity by a wind guide plate to level a sand dune. Results show that the threshold velocity for sand movement is 3.32 m/s at 10 cm above the sand surface in Ulan Buh Desert. A wind guide plate set at an angle less than 50° could significantly increase the wind velocity. The wind velocity could be accelerated up to the threshold velocity for sand movement behind a plate when the plate is at the angles of 20°, 25°, 35° and 40°. The most significant acceleration of wind velocity appears at 1.5 and 3.0 m behind the plate with an angle of 25°. An obvious wind velocity acceleration zone exists behind the wind guide plate when the angles are at 25°, 35°, 40° and 45°, with the most obvious zone under the angle of 45°. The results also show that the total amount of sand transferred over the experimental period increased by 6.1% under the effects of wind guide plates compared to the sand moved without wind guide plates. The results of the study will provide theoretical and practical supports for desert management in sand dune areas.

关键词： wind guide plate sand dune dune leveling wind velocity sandy desert Ulan Buh Desert

电针水沟穴对脑梗死模型大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基mRNA表达的影响

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甘肃中医药大学学报 2021年第6期38卷 1-6页

作者：徐彦龙徐秀梅杨正飞郭茂娟姜希娟甘肃省中医院针灸一科甘肃兰州730050 甘肃省中医院康复医学科甘肃兰州730050 天津中医药大学研究生院天津300193 天津中医药大学中西医结合学院天津300193

目的观察电针水沟穴对脑梗死模型大鼠脑血管平滑肌中细胞膜电压依赖性钙通道(VDCC)L型钙通道α1C亚基及受体门控钙通道(ROCC)瞬时受体电位通道6(TRPC6)亚基m RNA表达的影响。方法将130只SPF级雄性Wistar大鼠采用随机数字表法分为空白组... 详细信息

目的观察电针水沟穴对脑梗死模型大鼠脑血管平滑肌中细胞膜电压依赖性钙通道(VDCC)L型钙通道α1C亚基及受体门控钙通道(ROCC)瞬时受体电位通道6(TRPC6)亚基m RNA表达的影响。方法将130只SPF级雄性Wistar大鼠采用随机数字表法分为空白组(10只)、假手术组(40只)、模型组(40只)、电针组(40只)4组,除空白组外,其余3组又随机分为术后3 h、6 h、12 h、24 h 4个时相,每个时相10只。以线栓法复制大脑中动脉闭塞(MCAO)大鼠模型。电针组在造模后即刻针刺水沟穴,以韩氏电针仪刺激20 min。各组大鼠分别于相应时间处死,在外科显微镜下分别分离、剪取梗死侧的大脑前动脉、中动脉、后动脉各8 mm,通过实时荧光定量聚合酶链反应(PCR)检测各组不同时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA的相对表达量。结果与空白组和假手术组比较,模型组各时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA相对表达量均明显上调,差异有统计学意义(P<0.05或P<0.01);与模型组比较,电针组各时相大鼠脑血管平滑肌中L型钙通道α1C亚基及TRPC6亚基m RNA相对表达量均明显下调,差异有统计学意义(P<0.05或P<0.01)。结论电针干预能显著抑制MCAO模型大鼠脑血管平滑肌中VDCC L型钙通道α1C亚基及ROCC TRPC6亚基m RNA表达的上调,从而抑制缺血后血管平滑肌痉挛,增加脑梗死区周围血流灌注。

关键词：脑梗死电针水沟穴脑血管平滑肌电压依赖性钙通道 L型钙通道 α1C亚基受体门控钙通道瞬时受体电位通道6 相对表达量大鼠

围封10年对荒漠草原群落物种多样性与优势种空间分布格局的影响

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生态学报 2024年第10期44卷 4334-4341页

作者：许宏斌苏艳龙张雷刘红梅刘丽英杨溢文李琳内蒙古自治区林业科学研究院呼和浩特010010 内蒙古大学生态与环境学院呼和浩特010021

围封是修复退化草原生态系统的主要措施之一,科学与优化围封方式是目前草地资源管理中急需解决的科学问题。以内蒙古围栏封育10年和未围封的荒漠草原为研究对象,分析围封和未围封对内蒙古荒漠草原群落物种多样性和优势种空间分布格局的... 详细信息

围封是修复退化草原生态系统的主要措施之一,科学与优化围封方式是目前草地资源管理中急需解决的科学问题。以内蒙古围栏封育10年和未围封的荒漠草原为研究对象,分析围封和未围封对内蒙古荒漠草原群落物种多样性和优势种空间分布格局的影响,旨在为荒漠草原的恢复与重建提供科学依据。结果显示:(1)围封10年显著提高了荒漠草原的植被盖度、密度、高度和地上生物量;(2)围封10年对Margalef多样性指数、Shannon-Wiener多样性指数、Simpson丰富度指数和Pielou均匀度指数无显著影响,但围封均低于未围封样地;(3)围封10年对优势种短花针茅(Stipa breviflora)及糙隐子草(Cleistogenes squarrosa)的空间分布格局有较为显著的影响,与未围封相比围封后糙隐子草的分布格局变得单一,短花针茅分布格局变得多样。总体看来,围封10年后,荒漠草原群落物种组成、物种优势度和优势种的空间分布格局均发生一定程度变化,反映出围封后草地生态系统中植物适应其生存环境的策略,围封方式应根据立地条件,科学制定围封年限以达到较好的生态恢复效果。

关键词：荒漠草原围栏封育优势种空间分布格局

合肥市2014～2016年大气污染物PM_(2.5)对居民循环系统疾病死亡效应的时间序列分析

同方期刊数据库博看期刊评论

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山东大学学报（医学版） 2018年第11期56卷 48-52,75页

作者：王志强徐艳龙肖长春冯晓亮郑莉李飞黄发源安徽省疾病预防控制中心环境卫生科安徽合肥230601 合肥市疾病预防控制中心环境与职业卫生科安徽合肥230061 安徽省疾病预防控制中心安徽合肥230601

目的评估合肥市2014～2016年PM_(2.5)日均浓度对循环系统疾病死亡效应的影响。方法从合肥市气象局、环保局获得2014～2016年气象、环保资料,从中国疾病预防控制中心的死因监测系统获取人群死亡资料。采用基于Poisson回归的广义线性模型... 详细信息

目的评估合肥市2014～2016年PM_(2.5)日均浓度对循环系统疾病死亡效应的影响。方法从合肥市气象局、环保局获得2014～2016年气象、环保资料,从中国疾病预防控制中心的死因监测系统获取人群死亡资料。采用基于Poisson回归的广义线性模型控制时间趋势、温度、相对湿度、星期几效应、法定节假日等因素,分析污染物PM_(2.5)浓度对因循环系统疾病死亡效应,包含当日(lag0)、滞后(lag1～lag5)和累积滞后(lag01～lag05)效应;分析了老年人组(≥60岁)和非老年人组(<60岁)间PM_(2.5)浓度与循环系统疾病死亡人数的影响,同时分析引入SO_2、NO_2、O_3污染物后,对PM_(2.5)浓度与循环系统疾病死亡人数效应的影响。结果 PM_(2.5)浓度对因循环系统疾病总死亡人数有显著影响,其中对当日(lag0)和累积滞后5 d(lag05)影响最大,lag0超额死亡危险风险(ER)为0. 53%(95%CI:0. 09%～0. 98%),lag05的ER为1. 01%(95%CI:0. 33%～1. 70%)。在老年人组(≥60岁)中,PM_(2.5)浓度对因循环系统疾病总死亡人数的效应更加显著,也是对lag0和lag05影响最大,lag0的ER为0. 57%(95%CI:0.11%～1. 03%); lag05的ER为1. 04%(95%CI:0. 33%～1. 76%)。而在非老年人(年龄<60岁)人群中,PM_(2.5)浓度对因循环系统疾病总死亡人数影响无统计学意义。在多污染物模型分析中,加入污染物SO_2、NO_2后,发现均可减弱PM_(2.5)对循环系统疾病死亡人群的影响,效应无统计学意义。结论 2014～2016年PM_(2.5)污染物能增加合肥地区循环系统疾病死亡人数,且在老年人中效应更显著。

关键词：空气污染 PM2. 5 循环系统疾病死亡时间序列

中国西部地区方沸石胶结相与碎屑岩次生优质储集层形成机制

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古地理学报 2014年第4期16卷 517-526页

作者：孙玉善刘新年张艳秋董尉凯徐彦龙师桂霞林艳波李安琼中国石油塔里木油田分公司勘探开发研究院新疆库尔勒841000 中国石油新疆油田分公司勘探开发研究院新疆克拉玛依831000 中国石油长庆油田分公司采油五厂陕西西安710018

含油气盆地碎屑岩次生优质储集层的发育，除了与广泛发育的方解石胶结相有关外，在中国西部还有一类与沸石族自生矿物胶结的成岩相有关，其中以溶蚀方沸石胶结相形成的次生优质储集层与油气聚集成藏又有十分密切的关联。经实例分析：与... 详细信息

含油气盆地碎屑岩次生优质储集层的发育，除了与广泛发育的方解石胶结相有关外，在中国西部还有一类与沸石族自生矿物胶结的成岩相有关，其中以溶蚀方沸石胶结相形成的次生优质储集层与油气聚集成藏又有十分密切的关联。经实例分析：与自生方沸石胶结有关的成岩相主要受控于扇（辫状河）三角洲前缘相带、火山岩物源和成岩早期的碱性环境；次生优质储集层的形成在时间上主要处于成岩中期 A 阶段，在空间上受控于邻近的烃源岩、圈闭和输导体的沟通。方沸石矿物在物理性质上具有抗压易溶（有机酸）作用，较其他常见的自生矿物（胶结物）相对优越，就方沸石易于溶蚀的特点而言是较为理想的自生矿物（胶结物）。其溶蚀对孔隙度的贡献率在50％～75％之间，发育几率占绝对优势。所以，在方沸石发育的相带中寻找以粒间溶蚀孔为主的优质储集层，具有可靠的操作性和现实性。

关键词：中国西部地区碎屑岩方沸石胶结相溶蚀作用优质储集层形成机制

Bolt-grouting combined support technology in deep soft rock roadway

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International Journal of Mining Science and Technology 2016年第5期26卷 777-785页

作者： Chen yanlong Meng Qingbin xu Guang Wu Haoshuai Zhang Guimin State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Department of Mining Engineering & Metallurgical Engineering Western Australian School of Mines Curtin University School of Mechanics and Civil Engineering China University of Mining & Technology

Analyzing the mineral composition, mechanical properties and ground stress testing in surrounding rock,the study investigated the failure mechanism of deep soft rock roadway with high stress. The boltgrouting combined support system was proposed to prevent such failures. By means of FLAC3D numerical simulation and similar material simulation, the feasibility of the support design and the effectiveness of support parameters were discussed. According to the monitoring the surface and deep displacement in surrounding rock as well as bolt axial load, this paper analyzed the deformation of surrounding rock and the stress condition of the support structure. The monitor results were used to optimize the proposed support scheme. The results of field monitors demonstrate that the bolt-grouting combined support technology could improve the surround rock strength and bearing capacity of support structure, which controlled the great deformation failure and rheological property effectively in deep soft rock roadway with high stress. As a result, the long term stability and safety are guaranteed.

关键词： Deep soft rock roadway Bolt-grouting support Numerical simulation Similar material simulation High stress

基于近15年国内期刊文献的针灸病谱变化规律研究

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亚太传统医药 2023年第10期19卷 168-172页

作者：李希贤曹小丽王小花蔡鹤云徐彦龙甘肃中医药大学甘肃兰州730000 济宁市中医院山东济宁272000 甘肃省中医院甘肃兰州730050

目的:分析近15年针灸临床文献,总结针灸病谱,分析病谱变化及其原因。方法:检索2006-2020年,中国生物医学文献数据库、中国期刊全文数据库(CNKI)、万方数据库(WANFANG)和维普数据库(VIP)中的针灸文献,进行整理分析,总结针灸病谱。比较197... 详细信息

目的:分析近15年针灸临床文献,总结针灸病谱,分析病谱变化及其原因。方法:检索2006-2020年,中国生物医学文献数据库、中国期刊全文数据库(CNKI)、万方数据库(WANFANG)和维普数据库(VIP)中的针灸文献,进行整理分析,总结针灸病谱。比较1978-2005年与2006-2020年文献,分析病谱变化情况及变化原因。结果:共纳入符合标准文献78474篇,包括564种病症,其中,疾病系统文献篇数前5位依次为肌肉骨骼系统和结缔组织疾病、神经系统、精神和行为障碍、泌尿生殖系统、消化系统;具体病症文献前10位依次为脑血管病及后遗症、颈椎病、腰椎间盘突出症、面神经麻痹、膝关节骨性关节炎、睡眠障碍、偏瘫、肩关节周围炎、抑郁症、糖尿病及并发症。结论:针灸疗法临床应用广泛,且适应证不断扩大。与1978-2005年病谱比较,病谱发生较大变化,删减62种病症,新增173种病症。病谱变化原因与针灸疗法的发展、发病率的变化、人们需求的提升、医学技术的进步等因素相关。

关键词：针灸疗法疾病谱适应证文献计量