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一种基于相位误差校正技术的快速启动晶体振荡器

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电子学报 2024年第4期52卷 1182-1188页

作者：王子轩王山虎王鑫姚佳飞张珺胡善文蔡志匡郭宇锋南京邮电大学集成电路科学与工程学院江苏南京210023 南京邮电大学射频与微组装技术国家地方联合工程实验室江苏南京210023

随着超低功耗(Ultra-Low Power,ULP)物联网(Internet of Things,IoT)系统的发展,采用能量注入技术的快速启动晶体振荡器因对IoT系统功耗影响巨大而逐渐成为研究热点.能量注入技术可以显著降低晶体振荡器的启动时间和启动能量,但是对注... 详细信息

随着超低功耗(Ultra-Low Power,ULP)物联网(Internet of Things,IoT)系统的发展,采用能量注入技术的快速启动晶体振荡器因对IoT系统功耗影响巨大而逐渐成为研究热点.能量注入技术可以显著降低晶体振荡器的启动时间和启动能量,但是对注入源的精度要求苛刻.为了扩大注入频偏容限以及实现高注入效率,本文提出了一种基于延迟锁定环的相位误差校正技术.该技术将注入频偏容限扩大到2%,启动过程的非注入持续时间仅为4个周期,实现了高效注入.本文所述晶体振荡器采用40 nm CMOS工艺设计并流片.在1.0 V电源电压下采用24 MHz晶体进行测试,当注入频偏高达2%时,实现了7.2μs的启动时间,启动能量为5.1 nJ.相比同频偏下的传统注入方案,启动时间缩短了99.66%.

关键词：相位误差校正晶体振荡器快速启动延迟锁定环能量注入

Pteridic acid hydrate and pteridic acid C produced by Streptomyces pseudoverticillus YN17707 induce cell cycle arrest

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Chinese Journal of Natural Medicines 2015年第6期13卷 467-470页

作者： HAN Bing LI wen-xin CUI Cheng-Bin Beijing Institute of Biomedicine Beijing Institute of Pharmacology and Toxicology

The present study aimed at identifying cell cycle inhibitors from the fermentation broth of Streptomyces pseudoverticillus YN17707. Activity-guided isolation was performed on ts FT210 cells. Compounds were isolated through various chromatographic methods and elucidated by spectroscopic analyses. Flow cytometry was used to evaluate the cell cycle inhibitory activities of the fractions and compounds. Two compounds were obtained and identified as pteridic acid hydrate(1) and pteridic acid C(2), which arrested the ts FT210 cells at the g0/g1 phase with the MIC values being 32.8 and 68.9 μmol·L-1, respectively. These results provide a basis for future development of Compounds 1 and 2 as novel cell cycle inhibitors for cancer therapy.

关键词： Cell cycle inhibitor Streptomyces pseudoverticillus Spirocyclic polyketide Pteridic acid Flow cytometry

老年骨质疏松性椎体压缩性骨折及再骨折的诊疗

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中国中西医结合杂志 2024年第5期44卷 517-520页

作者：刘保新广州医科大学附属中医医院骨伤科广州510015

骨质疏松症(osteoporosis,OP)是以骨量减少,骨超微结构退化为特征,致骨脆性增加,易于骨折的一种老年骨骼疾病。近年来,我国逐步步入老年社会,OP患者逐年增多,骨质疏松性骨折(osteoporotic fracture,OF)的发病率也呈现出上升的趋势^([1,... 详细信息

骨质疏松症(osteoporosis,OP)是以骨量减少,骨超微结构退化为特征,致骨脆性增加,易于骨折的一种老年骨骼疾病。近年来,我国逐步步入老年社会,OP患者逐年增多,骨质疏松性骨折(osteoporotic fracture,OF)的发病率也呈现出上升的趋势^([1,2])。OP的三大并发症为疼痛、脊柱变形和骨折。其中,骨折危害最大,即脆性骨折。OF多发生于脊柱、桡骨远端、肱骨近端与髋部等部位。其中,50%以上OF发生于脊柱,好发于胸腰椎^([3,4])。

关键词：骨质疏松性骨折骨量减少桡骨远端再骨折肱骨近端老年骨质疏松性椎体压缩性骨折脆性骨折骨骼疾病

Secure mediated certificateless signature scheme

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 75-78页

作者： YANg Chen MA wen-ping wa.g xin-mei Ministry of Education Key Laboratory of Computer Networks and Information Security Xidian University Xi'an 710071 China

Ju et al. proposed a certificateless signature scheme with instantaneous revocation by introducing security mediator （SEM） mechanism. This article presents a detailed cryptoanalysis of this scheme and shows that, in their proposed scheme, once a valid signature has been produced, the signer can recover his private key information and the instantaneous revocation property will be damaged. Furthermore, an improved mediated signature scheme, which can eliminate these disadvantages, is proposed, and security proof of the improved scheme under elliptic curve factorization problem （ECFP） assumption and bilinear computational diffie-hellman problem （BCDH） assumption is also proposed.

关键词： certificateless signature scheme bilinear pairing security mediator

极端天气与区域金融风险:推波助澜还是波澜不惊?

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现代金融研究 2024年第9期29卷 59-69页

作者：张庆君赵志尚孟新新天津财经大学金融学院天津300222 天津财经大学金融与保险研究中心天津300222 天津财经大学金融学院

本文以2011年至2020年期间208个中国地级及以上城市为样本,检验极端天气对区域金融风险的影响。研究发现,极端降水主要通过增加经济损失和降低生产效率显著影响区域金融风险,而极端气温和大风对区域金融风险没有显著影响。同时,极端天... 详细信息

本文以2011年至2020年期间208个中国地级及以上城市为样本,检验极端天气对区域金融风险的影响。研究发现,极端降水主要通过增加经济损失和降低生产效率显著影响区域金融风险,而极端气温和大风对区域金融风险没有显著影响。同时,极端天气对区域金融风险的影响存在着规模、区位、赋和政策异质性,拓展保险广度、增加保险深度、推广环境保险和强化减排降碳均有利于弱化极端天气对区域金融风险的影响。

关键词：极端天气金融风险气候金融气候风险

Numerical simulation of slurry jets using mixture model

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water Science and Engineering 2013年第1期6卷 78-90页

作者： wen-xin HUAI wan-yun XUE Zhong-dong QIAN State Key Laboratory of water Resources and Hydropower Engineering Science Wuhan University

Slurry jets in a static uniform environment were simulated with a two-phase mixture model in which flow-particle interactions were considered. A standard k-e turbulence model was chosen to close the governing equations. The computational results were in agreement with previous laboratory measurements. The characteristics of the two-phase flow field and the influences of hydraulic and geometric parameters on the distribution of the slurry jets were analyzed on the basis of the computational results. The calculated results reveal that if the initial velocity of the slurry jet is high, the jet spreads less in the radial direction. When the slurry jet is less influenced by the ambient fluid （when the Stokes number St is relatively large）, the turbulent kinetic energy k and turbulent dissipation rate e, which are relatively concentrated around the jet axis, decrease more rapidly after the slurry jet passes through the nozzle. For different values of St, the radial distributions of streamwise velocity and particle volume fraction are both self-similar and fit a gaussian profile after the slurry jet fully develops. The decay rate of the particle velocity is lower than that of water velocity along the jet axis, and the axial distributions of the centerline particle streamwise velocity are self-similar along the jet axis. The pattern of particle dispersion depends on the Stokes number St. When St = 0.39, the panicle dispersion along the radial direction is considerable, and the relative velocity is very low due to the low dynamic response time. When St = 3.08, the dispersion of particles along the radial direction is very little, and most of the particles have high relative velocities along the streamwise direction.

关键词： slurry jet," numerical simulation," two-phase mixture model Stokes number,"flow-particle interaction

Nonmetallic Inclusion Control of 350 km/h High Speed Rail Steel

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Journal of Iron and Steel Research International 2009年第3期16卷 20-26,36页

作者： ZHAO Ke-wen ZENg Jian-hua wa.g xin-hua School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing100083 China Panzhihua Iron and Steel (group) Co Panzhihua 617067 Sichuan China

Inclusion has an important effect on quality of high speed rail steel. In consideration of the lower acceptance percentage of the inclusion and its constraint against the requirement for large scale production of 350 km/h high speed rail steel in Panzhihua Iron and Steel （group） Co,the technology of nonmetallic inclusion control for 350 km/h high speed rail steel was studied. An optimized model of the argon-blowing in ladle furnace （LF）,the control of the components of the ladle slag,and the technique of calcium treatment for the molten steel was brought forward. Using the researched technology,the removal ratio of the inclusion was increased and the components,distribution,and shape of the inclusion in the rail steel were changed,which resulted in a reduction in the average total oxygen content to 10.17×10^-6 and an increase in the comprehensive acceptance percentage of the nonmetallic inclusion from 48.21% to 98.1%. Test has shown that this metallurgical technology can meet the requirement for large scale production of 350 km/h high speed steel in Panzhihua Iron and Steel （group） Co.

关键词： high Speed rail steel inclusion refining calcium treatment total oxygen content

印度殉葬寡妇的颠覆与重塑:“女英雄”与“牺牲品”之外的“迦梨女神”

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外语导刊 2024年第3期47卷 63-71,159页

作者：刘鑫尹晶北京科技大学外国语学院北京100083

在印度主流历史和政治话语中,殉葬寡妇要么被描述为“女英雄”,要么被描述为“牺牲品”,却未发出过自己的声音。阿米塔夫·高希和娜扬达拉·萨加尔在《罂粟海》和《像我们一样富有》中分别塑造迪提和曾祖母两个人物,为挖掘这一边缘群体... 详细信息

在印度主流历史和政治话语中,殉葬寡妇要么被描述为“女英雄”,要么被描述为“牺牲品”,却未发出过自己的声音。阿米塔夫·高希和娜扬达拉·萨加尔在《罂粟海》和《像我们一样富有》中分别塑造迪提和曾祖母两个人物,为挖掘这一边缘群体的声音进行了积极探索。本文借助古哈、查特吉、南迪、斯皮瓦克等印度(印裔)学者的相关思想,深入分析两位小说人物所处的生存困境,揭示了印度父权制、英国殖民主义和印度民族主义等力量对殉葬寡妇的剥削和压迫,以及这两位殉葬寡妇展开的积极和消极反抗,认为两部小说颠覆了“女英雄”和“牺牲品”这两种传统的殉葬寡妇形象,重塑了不同的“迦梨女神”式殉葬寡妇形象,展现了她们被主流话语遮蔽或忽略的庶民意识和异质性主体经验。

关键词：印度阿米塔夫·高希娜扬达拉·萨加尔罂粟海像我们一样富有父权制殉葬寡妇

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风险制造与风险规避:基层政府的行为逻辑

华南农业大学学报（社会科学版） 2024年第3期23卷 132-140页

作者：陈文琼中南大学公共管理学院湖南长沙410083

通过对Z省S县和H省X县的田野调查,发现基层政府存在一定的制造风险的行为,主要表现为逾越上级政府对其行为所设定的规范或要求,其背后的动机往往是为了增加财政可支配收入或扩大对基层有限财政的支配权,从而缓解财政供需之间的矛盾;该... 详细信息

通过对Z省S县和H省X县的田野调查,发现基层政府存在一定的制造风险的行为,主要表现为逾越上级政府对其行为所设定的规范或要求,其背后的动机往往是为了增加财政可支配收入或扩大对基层有限财政的支配权,从而缓解财政供需之间的矛盾;该行为生成于县域财政资金匮乏与横向竞争结构下政绩压力的双重挤压,由于“资源密集型”政绩的路径依赖,政府产生了大量的财政资源诉求,然而这种需求却难以通过当前匮乏的财政资源得到满足;为了将制造的风险限定在可控的范围之内,迎检、维稳和精英俘获都是基层转而采取的风险规避行为策略。

关键词：风险制造风险规避财政收入 “资源密集型”政绩