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An Arctic sea ice thickness variability revealed from satellite altimetric measurements

Acta Oceanologica Sinica 2014年第11期33卷 134-140页

作者： bi Haibo HUANG Haijun SU qiao YAN Liwen LIU Yanxia XU Xiuli Key laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences The First Institute of Oceanology State Oceanic Administration

A modified algorithm taking into account the first year（FY） and multiyear（MY） ice densities is used to derive a sea ice thickness from freeboard measurements acquired by satellite altimetry ICESat（2003–2008）. Estimates agree with various independent in situ measurements within 0.21 m. Both the fall and winter campaigns see a dramatic extent retreat of thicker MY ice that survives at least one summer melting season. There were strong seasonal and interannual variabilities with regard to the mean thickness. Seasonal increases of 0.53 m for FY the ice and 0.29 m for the MY ice between the autumn and the winter ICESat campaigns, roughly 4–5 month separation, were found. Interannually, the significant MY ice thickness declines over the consecutive four ICESat winter campaigns（2005–2008） leads to a pronounced thickness drop of 0.8 m in MY sea ice zones. No clear trend was identified from the averaged thickness of thinner, FY ice that emerges in autumn and winter and melts in summer. Uncertainty estimates for our calculated thickness, caused by the standard deviations of multiple input parameters including freeboard, ice density, snow density, snow depth, show large errors more than 0.5 m in thicker MY ice zones and relatively small standard deviations under 0.5 m elsewhere. Moreover, a sensitivity analysis is implemented to determine the separate impact on the thickness estimate in the dependence of an individual input variable as mentioned above. The results show systematic bias of the estimated ice thickness appears to be mainly caused by the variations of freeboard as well as the ice density whereas the snow density and depth brings about relatively insignificant errors.

关键词： satellite altimetry ice thickness Arctic first-year ice multiyear ice

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Copper partitioning between granitic silicate melt and coexisting aqueous fluid at 850°C and 100 MPa

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Acta Geochimica 2016年第4期35卷 381-390页

作者： Shuilong Wang Hui Li Linbo Shang Xianwu bi Xinsong Wang Wenlin Fan State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Geophysical Exploration Institute of Heilongjiang Province Harbin 150036China University of Chinese Academy of Sciences Beijing 100039China

Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 °C, 100 MPa and oxygen fugacity(f O_2) buffered at approaching Ni–Ni O(NNO). Partition coefficients of Cu(DCu= cfluid/cmelt) were varied with different alumina/alkali mole ratios [Al_2O_3/(Na_2O·K_2O), abbreviated as Al/Alk], Na/K mole ratios, and Si O_2 mole contents. The DCu increased from 1.28 ± 0.01 to 22.18 ± 0.22 with the increase of Al/Alk mole ratios(ranging from 0.64 to 1.20)and Na/K mole ratios(ranging from 0.58 to 2.56). The experimental results also showed that DCuwas positively correlated with the HCl concentration of the starting *** DCuwas independent of the Si O_2 mole content in the range of Si O_2 content considered. No DCuvalue was less than 1 in our experiments at 850 °C and 100 MPa, indicating that Cu preferred to enter the fluid phase rather than the coexisting melt phase under most conditions in the melt-fluid system, and thus a significant amount of Cu could be transported in the fluid phase in the magmatichydrothermal environment. The results indicated that Cu favored partitioning into the aqueous fluid rather than themelt phase if there was a high Na/K ratio, Na-rich, peraluminous granitic melt coexisting with the high Cl-fluid.

关键词：硅酸盐熔体花岗质熔体分配系数水溶液 MPa 共存 SiO2含量碱摩尔比

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Role of ultrasound in colorectal diseases

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World Journal of Gastroenterology 2016年第43期22卷 9477-9487页

作者： Renáta Bor Anna Fábián Zoltán Szepes First Department of Medicine University of Szeged

Ultrasound is an undervalued non-invasive examination in the diagnosis of colonic diseases. It has been replaced by the considerably more expensive magnetic resonance imaging and computed tomography, despite the fact that, as first examination, it can usefully supplement the diagnostic process. Transabdominal ultrasound can provide quick information about bowel status and help in the choice of adequate further examinations and treatment. Ultrasonography,as a screening imaging modality in asymptomatic patients can identify several colonic diseases such as diverticulosis, inflammatory bowel disease or cancer. In addition, it is widely available, cheap, non-invasive technique without the use of ionizing radiation, therefore it is safe to use in childhood or during pregnancy, and can be repeated at any time. New ultrasound techniques such as elastography, contrast enhanced and Doppler ultrasound, miniprobes rectal and transperineal ultrasonography have broadened the indication. It gives an overview of the methodology of various ultrasound examinations, presents the morphology of normal bowel wall and the typical changes in different colonic diseases. We will pay particular attention to rectal and transperineal ultrasound because of their outstanding significance in the diagnosis of rectal and perineal disorders. This article seeks to overview the diagnostic impact and correct indications of bowel ultrasound.

关键词：超声会阴的超声直肠的 endosonography 胃肠的疾病

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On the mechanism and control for the ultra-low frequency oscillation in NY Power Grid with large-scale hydropower

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Control Theory and Technology 2019年第3期17卷 241-251页

作者： Ancheng XUE Jiawei WANG Chao ZHENG Joe H.CHOW Tianshu bi State Key Laboratory of Alternate Electrical Power System with Renewable Energy Source (North China Electric Power University) Changping District Beijing 102206 China China Electric Power Research Institute Haidian District Beijing 100192 China Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute Troy 12180 New York State U.S.A.

The power grid with large proportion of hydropower may engage the ultra-low frequency oscillation (ULFO),which threatening the operation of *** the NY Power Grid system,whose dimension is over thousands,this paper reveals the cause of ULFO with the phase portrait method,i.e.,lies in the saturation of the different limits of the governor system of the generators,in other words,the occurrence of limit cycle is due to the non-smooth *** furthermore,it proposes two methods to suppress ULFO with the philosophy of destroying the condition of non-smooth *** detail,first,the phenomenon of ULFO in NY Power Grid,the damping characteristics and the limits in the governor system of the hydropower units are ***,based on the non-smooth bifurcation theory,the mathematical basis of the oscillation in the non-smooth system caused by the saturation of limits is *** then,the non-oscillation and oscillation dynamic of the system corresponding to without/with limits in the governor system are ***,it discusses the influence of the saturation of single limit on the characteristics of ULFO with the phase ***,the phase portraits of the ULFO under different faults is analyzed,and it shows that the limiting saturation occurs with a large enough ***,the ULFO is resulting from the negative damping of generation and the saturation of multiple limits under a large enough *** addition,according to the above mechanism,two strategies to suppress the ULFO,i.e.,the governor parameters tuning and the fault strength relief are *** simulation shows the effectiveness of proposed strategies.

关键词： Ultra -low frequency oscillatio n gover nor system limit no rnsmooth bifurcation limit cycle

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Small-signal Angular Stability of Power System as Affected by Grid-connected Variable Speed Wind Generators—A Survey of Recent Representative Works

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CSEE Journal of Power and Energy Systems 2017年第3期3卷 223-231页

作者： Wenjuan Du Jingtian bi H.F.Wang State Key Laboratory of Alternate Electric Power Systems(SKLAEPS)with New Energy Resources North China Electric Power UniversityBeijing 102206China

This paper reviews the status and progress of the investigation on power system small-signal angular stability as affected by grid-connected variable speed wind generators(VSWGs).The review is carried out on the basis of a survey of recently published representative *** of the investigation made in those selected papers are classified into two groups:1)VSWGs displacing synchronous generators(SGs);2)VSWGs simply being added in a power *** diversification of the results of the investigation is highlighted in the *** analysis on two strategies of the investigation is conducted in this *** is revealed that in the strategy of VSWGs displacing SGs,there are two factors which could affect power system small-signal angular stability differently:1)Withdrawing the SGs’dynamics;2)adding the VSWGs’*** the strategy of adding VSWGs in the power system,there are also two affecting factors:1)Change of load flow brought about by the VSWGs;2)dynamic interactions with the SGs introduced by the *** diversified results of the investigation obtained so far are not only due to the dependence of the investigation on sample power systems used,but also caused by the mixture of different affecting *** paper is concluded with a summary of key issues of the investigation for future work.

关键词： Electromechanical oscillation modes power system dynamics power system low-frequency oscillation power system small-signal angular stability synchronous generators(SGs) variable speed wind generators(VSWGs)

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考虑云层影响的大型光伏发电系统辐照强度计算模型

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中国电机工程学报 2015年第17期35卷 4291-4299页

作者：丁明徐志成赵波毕锐安徽省新能源利用与节能实验室(合肥工业大学) 安徽省合肥市230009 国网浙江省电力公司电力科学研究院浙江省杭州市310014

该文模拟云层遮阴导致大型光伏发电系统辐照强度空间分布不均的情形,在考虑太阳辐射随时间变化的同时重点分析了因云层移动导致的太阳辐射空间分布的随机性和不确定性。首先计算任意地点任意时刻的天文辐射强度,依次考虑大气层衰减、电... 详细信息

该文模拟云层遮阴导致大型光伏发电系统辐照强度空间分布不均的情形,在考虑太阳辐射随时间变化的同时重点分析了因云层移动导致的太阳辐射空间分布的随机性和不确定性。首先计算任意地点任意时刻的天文辐射强度,依次考虑大气层衰减、电站所在区域的云层的动态影响,计算到达水平地面的辐照强度,最终得到光伏组件倾斜面上的辐照强度。该模型考虑了地形地貌对日出日落时间的影响、云层分布特性及其和天气的相关性、不同类型的云层透光率、"云隙效应"、云层重叠及云层边缘效应,并能以较高时间分辨率进行仿真计算。由于综合考虑了辐照强度的确定性和随机性部分,该模型对研究光伏发电系统暂稳态分析、实时控制及并网光伏发电对电网的影响具有参考意义。

关键词：光伏发电辐照强度云层阴影相关矩阵云隙效应云层透光率

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PandA(Box)flies on Bluesky:maintainable and user-friendly fly scans with Mamba at HEPS

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Radiation Detection Technology and Methods 2023年第4期7卷 493-501页

作者： Peng-Cheng Li Cheng-Long Zhang Yu-Jun Zhang Chun Li Zhi-Ying Guo Ge Lei Yi Zhang Ai-Yu Zhou Xiao-Xue bi Yu Liu Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Beijing100049China

Purpose Fly scans are indispensable in many experiments at the High Energy Photon Source(HEPS).PandABox,the main platform to implement fly scans at HEPS,needs to be integrated into Mamba,the experiment control system developed at HEPS based on *** In less than 600 lines of easily customisable and extensible backend code,provided are full control of PandABox’s TCP server in native ophyd,automated configuration(also including wiring)of“PandA blocks”for constant-speed mapping experiments of various dimensions,as well as generation of scans deliberately fragmented to deal with hardware limits in numbers of exposure frames or sequencer table *** The upper-level control system for PandABox has been ported to Bluesky,enabling the combination of both components’flexibility in fly-scan *** on this backend,a user-friendly Mamba frontend is developed for X-ray fluorescence(XRF)mapping experiments,which provides fully online visual feedback.

关键词： Fly scan PandABox Bluesky Mamba XRF mapping

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朱熹对程颐中和学说的继承与重构

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浙江大学学报（人文社会科学版） 2023年第6期53卷 157-167页

作者：毕梦曦东南大学人文学院江苏南京211189

程颐释“中和”有很强的辟佛老意识,他不认为心理活动存在一个虚静而天道显露的阶段,也不希望学者在思虑和情感都未生发之时寻找纯粹的天道。朱熹认为程颐就中和问题曾进行过自我修正,这一观点在今天值得重新考察与检视,《与吕大临论中... 详细信息

程颐释“中和”有很强的辟佛老意识,他不认为心理活动存在一个虚静而天道显露的阶段,也不希望学者在思虑和情感都未生发之时寻找纯粹的天道。朱熹认为程颐就中和问题曾进行过自我修正,这一观点在今天值得重新考察与检视,《与吕大临论中书》中“凡言心者皆指已发”与“寂然不动,感而遂通”等文献细节也应放回二程文献语境重新考察与理解。朱熹的中和旧说在具体字句的训诂上虽与程颐存在龃龉,但从思想上基本继承了程颐的主要心性论观点。到了中和新说阶段,朱熹则在继承程颐中和思想的基础上完成了对程颐心性论的结构性重构,不仅认为未发与已发存在体用关系,而且认为在未发阶段学者可以体会到“一性浑然,道义全具”,将道学的心性理论推向完备与精致。

关键词：朱熹程颐中和诠释

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东盟国家社交媒体政治假新闻治理研究

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南洋问题研究 2022年第4期 65-78页

作者：毕世鸿宋洋云南大学“一带一路”研究院云南昆明650091 云南大学周边外交研究中心云南昆明650091 云南大学国际关系研究院云南昆明650091

随着数字媒体的高速发展,政治假新闻在社交媒体平台的传播严重威胁东盟国家的社会和谐、政治稳定和国家安全。为应对该挑战,东盟各国不仅在区域层面上构建合作框架、开展经验交流,而且在国内也采取修订和出台法律规范、增设审核机构、... 详细信息

随着数字媒体的高速发展,政治假新闻在社交媒体平台的传播严重威胁东盟国家的社会和谐、政治稳定和国家安全。为应对该挑战,东盟各国不仅在区域层面上构建合作框架、开展经验交流,而且在国内也采取修订和出台法律规范、增设审核机构、扩大教育培训等多种方式予以应对,并将媒体机构、科技公司、社会组织等非政府行为体的协同审核监督纳入治理进程中。这些措施在一定程度上规范了东盟国家社交媒体的信息环境,但受制于东盟各国差异化的政治环境和法律制度等因素,社交媒体政治假新闻的治理工作任重道远。

关键词：东盟国家社交媒体政治假新闻

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Effects of Sand Grain Size on Habitat Selection in Steppe Toad-headed Lizard(Phrynocephalus frontalis)

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Asian Herpetological Research 2017年第2期18卷 123-130页

作者： Shengnan JI Xue LIAN Zhigang JIANG Lili LI Junhuai bi Chunwang LI Key Laboratory of Animal Ecology and Conservation biology Institute of Zoology Chinese Academy of Sciences College of Life Science Inner Mongolia Normal University College of Life Science University of Chinese Academy of Sciences

To understand the effects of sand grain size on habitat selection, we conducted a field study on the steppe toad-headed lizard in Hunshandake Desert northern China. Methods of mark-recapture and transect survey were used to investigate the density of steppe toad-headed lizards and the environmental variables. The comparison on lizard densities among the habitats with different environmental factors revealed that： 1） population density of the steppe toad-headed lizard differed significantly among the habitats with different sand grain size indexes（SGSIs, representing roughness of sand substrate）： the highest lizard density was found in the group with an SGSI of 〉 0.30, whereas the lowest density was found in the group with an SGSI of 0–0.15; and 2） vegetation cover, soil moisture, invertebrate diversity index, and abundance had no significant effects on the lizard density. These results implied that the sand grain size was the most important determinant of habitat selection for steppe toad-headed lizards in Hunshandake Desert. Steppe toad-headed lizards could avoid structural habitats that have negative effects on their maximal sprinting capabilities. Considering the changing sand grain size in the development phase of sand dunes, the sand lizard could be used as an indicator of the process of desertification.

关键词： habitat preference agama lizard sand substrate desert grassland

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