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Precise orbit determination for GRACE with zero-difference kinematic method

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Chinese Science Bulletin 2010年第7期55卷 600-606页

作者： LI JianCheng ZHANG ShouJian zou XianCai JIANG WeiPing School of Geodesy and Geomatics Wuhan University Wuhan 430079 China GNSS Researeh Center Wuhan University Wuhan 430079 China

Thanks to the high performance of the spaceborne GPS receiver and the availability of precise IGS orbit and clock products,zero-difference kinematic precise orbit determination(POD) has been turned out to be a new effective method in orbit determination for the LEO ***-difference kinematic POD,which is based on the GPS measurements only from the spaceborne GPS receiver,does not depend on the force models and orbit *** this point of view,kinematic POD is suitable for the Earth observation satellites at very low altitudes,such as CHAMP,GRACE and GOCE,*** paper first reviews the basic zero-difference GPS observation *** a modified data quality control scheme is put ***,a block-wise least squares algorithm,which first separates the parameters into several groups and then solves the parameters by elimination and back-substitution,is discussed and proposed for the kinematic orbit *** the above algorithms,we developed kinematic POD software to solve the orbit suitable for one-week GRACE *** with the published Rapid Science Orbit(RSO) indicate that,using our approach to determine the orbit,the accuracy in the radial direction can achieve 3―4 cm for GRACE-A,and 3―5 cm for GRACE-B.

关键词：轨道确定运动学零重力星载GPS接收机过氧化物酶最小二乘算法地球观测卫星快速科学轨道

低浓度聚丙烯酰胺含量的检测及溶液离子的影响

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工程科学学报 2024年第6期46卷 1012-1023页

作者：饶博邹文杰赵伟余可馨北京低碳清洁能源研究院煤炭开采水资源保护与利用国家重点实验室北京102211 北京科技大学土木与资源工程学院北京100083

处理后选矿废水中残余的聚丙烯酰胺(PAM)影响回水水质及其回用,本文为建立一种低检出限的低浓度PAM快速检测方法,在190~300 nm波长范围内建立了4种类型及分子量不同PAM的紫外吸收光谱,研究了不同浓度K^(+)和Ca^(2+)对PAM浓度检测的影响... 详细信息

处理后选矿废水中残余的聚丙烯酰胺(PAM)影响回水水质及其回用,本文为建立一种低检出限的低浓度PAM快速检测方法,在190~300 nm波长范围内建立了4种类型及分子量不同PAM的紫外吸收光谱,研究了不同浓度K^(+)和Ca^(2+)对PAM浓度检测的影响,并通过原子力显微镜(AFM)分析了PAM分子构象的变化.结果表明,4种类型的PAM峰值吸光度均在波长194 nm处测得,PAM浓度与吸光度之间具有强线性关系(R^(2)>0.98),检出限均低于0.1 mg·L^(-1),但PAM类型影响其浓度与吸光度的线性关系.随着K^(+)和Ca^(2+)浓度的增加,PAM溶液吸光度特征峰的强度逐渐降低并降速减缓,最大吸收波长不断红移,分别沉积在二氧化硅和金基底的APAM-3与CPAM-12的表面形貌粗糙度分别随K^(+)和Ca^(2+)浓度的增加而增大,说明PAM分子链在溶液中的构象逐渐变卷曲,使紫外光谱特征吸收峰的峰值降低,10、100 mmol·L^(-1) K^(+)与1、10 mmol·L^(-1) Ca^(2+)对PAM构象变化的影响程度基本相同.本研究实现聚丙烯酰胺的快速定量检测,对开展选矿水处理中聚丙烯酰胺的迁移规律研究具有重要意义.

关键词：紫外分光光度法聚丙烯酰胺浓度检测溶液离子原子力显微镜(AFM)

Contact performance analysis of pressure controller's sealing interface in deep in-situ pressure-preserved coring system

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Petroleum Science 2022年第3期19卷 1334-1346页

作者： Jia-Nan Li Jun Wang yun-Qi Hu Zhen-Xi You Meng Xu Ying-Wei Wang Zu-Jie zou Qi-yue Kang School of Mechanical Engineering MOE Key Laboratory of Deep Underground Science and EngineeringCollege of Water Resource and HydropowerSichuan UniversityChengdu610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518061China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization Pingdingshan Tianan Coal Mining Co.LTD.Pingdingshan467000China Xi'an Research Institute China Coal Technology&Engineering Group CorpXi'an710077China

The sealing performance of contact interfaces plays the most important role in the design and operation of the in-situ pressure-preserved coring *** meet the demand of ultra-high pressure-retained coring for oil and gas exploration in deep reservoirs,a quantitative analysis of the contact mechanical behavior of the pressure controller was *** on the micro-contact theory of rough surfaces,a three-dimensional numerical model of the rough contact interface between the valve cover and the valve seat was constructed,and the micro-contact behavior of the metal contact surfaces was comprehensively *** results show that the actual contact area of the valve interface increases with the increase of surface roughness before the critical contact point,but decreases after *** with the real contact model with double rough surfaces,although the simplified hard-contact model with a single rough surface can reflect the micro-contact behavior of the rough surface to a certain extent,it cannot truly reveal the microchannel morphology between the sealing interfaces under ***,the realistic double-rough-surface model should be recommended to evaluate the sealing performance of coring tools,particularly for high pressure *** material properties of valves have a significant effect on the contact characteristics of rough surfaces,which suggested that the actual contact area decreases with the increase of the elastic modulus of the contact material under the same loading *** knowledge of this work could help to enhance the seal design of pressure controllers for in-situ pressure-preserved coring.

关键词： In-situ pressure-preserved coring Metal seal Rough surface Micro contact

Adaptive compression method for underwater images based on perceived quality estimation

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Frontiers of Information Technology & Electronic Engineering 2019年第5期20卷 716-730页

作者： Ya-qiong CAI Hai-xia zou Fei yuAN Key Laboratory of Underwater Acoustic Communication and Marine Information Technology Ministry of Education Xiamen University Xiamen 361005 China

Underwater image compression is an important and essential part of an underwater image transmission system. An assessment and prediction method of effectively compressed image quality can assist the system in adjusting its compression ratio during the image compression process, thereby improving the efficiency of the image transmission system. This study first estimates the perceived quality of underwater image compression based on embedded coding compression and compressive sensing, then builds a model based on the mapping between image activity measurement(IAM) and bits per pixel and structural similarity(BPP-SSIM) curves, next obtains model parameters by linear fitting, and finally predicts the perceived quality of the image compression method based on IAM, compression ratio, and compression strategy. Experimental results show that the model can effectively fit the quality curve of underwater image compression. According to the rules of parameters in this model, the perceived quality of underwater compressed images can be estimated within a small error range. The presented method can effectively estimate the perceived quality of underwater compressed images, balance the relationship between the compression ratio and compression quality, reduce the pressure on the data cache, and thus improve the efficiency of the underwater image communication system.

关键词： Underwater image compression Set partitioning in hierarchical trees Compressive sensing Compression quality estimation

双端柔性低频输电系统低频侧两相运行控制策略

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电力系统自动化 2022年第19期46卷 132-144页

作者：吴小丹卢宇董云龙邹强南京南瑞继保电气有限公司江苏省南京市211102 南瑞集团有限公司(国网电力科学研究院有限公司) 江苏省南京市211106

基于模块化多电平矩阵变换器(M3C)的柔性低频输电系统(LFTS)具备低频侧两相运行能力,但其控制策略需特殊设计。文中首先介绍了双端柔性LFTS的基本情况及两相运行的基本要求,给出基于工、低频侧输入解耦及桥臂环流控制的M3C数学模型。为... 详细信息

基于模块化多电平矩阵变换器(M3C)的柔性低频输电系统(LFTS)具备低频侧两相运行能力,但其控制策略需特殊设计。文中首先介绍了双端柔性LFTS的基本情况及两相运行的基本要求,给出基于工、低频侧输入解耦及桥臂环流控制的M3C数学模型。为实现低频侧不对称运行条件下桥臂子模块电容电压的均衡,提出M3C桥臂功率再平衡的双重低频环流控制法。然后,分别给出两相运行条件下V/f站和PQ站的低频侧输入电流控制策略,并在静止坐标系统通过对9个桥臂电流的完全独立控制实现两个站M3C的控制。最后,在实时数字仿真系统中搭建双端柔性LFTS仿真模型,分别对稳态、动态及交流系统不对称故障等典型工况进行仿真测试。仿真测试结果表明,所提控制策略可有效实现双端柔性LFTS的低频侧两相运行要求。

关键词：柔性低频输电模块化多电平矩阵变换器双端系统两相运行低频环流控制

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多因素影响下的驾驶舱拨动开关反应时研究

北京航空航天大学学报 2024年第8期50卷 2413-2420页

作者：靳慧斌杨瑜常银霞邹国良中国民航大学交通科学与工程学院天津300300 中国民航大学安全科学与工程学院天津300300 中国民航大学电子信息与自动化学院天津300300 中国民用航空局北京100710

针对飞行员操纵驾驶舱拨动开关的反应时问题,通过搭建飞行模拟实验舱,采集飞行员操纵驾驶舱拨动开关的反应时数据,应用多因素方差分析方法,研究在多因素影响下,影响飞行员反应时的因素。结果表明:驾驶舱拨动开关位于飞行员正前方左侧水... 详细信息

针对飞行员操纵驾驶舱拨动开关的反应时问题,通过搭建飞行模拟实验舱,采集飞行员操纵驾驶舱拨动开关的反应时数据,应用多因素方差分析方法,研究在多因素影响下,影响飞行员反应时的因素。结果表明:驾驶舱拨动开关位于飞行员正前方左侧水平斜向下45°的面板,反应时最短;规定正确的操作开关方向为向前为正,相比方向为向后为正,飞行员的操纵反应时更短;高负荷因素下,飞行员反应时更长;有灯光引导条件下可以降低飞行员的反应时;面板位置、负荷处理、灯光引导3种因素主体之间的交互作用对飞行员操纵驾驶舱拨动开关的反应时的影响显著。通过实验研究与数据处理分析,结果客观真实,有助于提升飞行员的飞行安全水平,也为操纵器件设计问题提供了基础实验研究和建议。

关键词：人机工效学驾驶舱拨动开关反应时影响因素

Impacts of climate change and land cover factor on runoff in the Coastal Chinese Mainland region

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Geography and Sustainability 2024年第4期5卷 526-537页

作者： Song Song Ziqiang Ye Zhijie Zhou Xiaowei Chuai Rui Zhou Jinwei zou Yi Chen School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China The Hong Kong University of Science and Technology(Guangzhou) Guangzhou 511453China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Jiangsu Provincial Academy of Social Sciences Nanjing 210004China Bao’an Institute of Education Sciences Shenzhen 518101China Zhejiang Design Institute of Water Conservancy and Hydroelectric Power Co. Ltd.Hangzhou 310002China

The increasingly frequent storms pose significant threats to the sustainable development of coastal regions,particularly in densely populated and economically vibrant *** the dynamics and intricate mechanisms underlying runoff generation is crucial in the context of climate change and anthropogenic *** on hydro-meteorological and land-use data from 1980 to 2018,this study investigates the runoff variation and its driving factors in the Coastal Chinese Mainland(CCM).The aims of this study are to reveal the temporal and spatial trends of runoff yield,to clarify the sensitivity of runoff in coastal cities to the integrated and individual parameters of climate change and anthropogenic interference,including precipitation(P),potential evapotranspiration(E0),and land cover factor(n),and to support the establishment of spatially tailored adaptation *** results show that:(1)runoff has generally increased over the study period,particularly in regions such as the Yangtze River Delta,Shandong,and Guangxi,while it has decreased in western Liaoning and eastern Guangdong;(2)in the northern CCM with larger aridity index,the land cover factor plays a dominant role in runoff production,while in the wetter southern CCM,precipitation is more influential,and potential evapotranspiration mainly hinders runoff generation all over CCM;(3)urban expansion tends to negatively impact n,while the loss of grasslands and shrinkage of croplands tend to undermine the value of *** facilitate the achievement of sustainable development goals in the CCM,it is imperative to introduce a more comprehensive and theoretical framework that encompasses the natural,technical,and social dimensions of human-water systems into traditional flood regulation and water resource *** framework should promote interdisciplinary collaboration from an integrated perspective,to bridge the administrative and watershed boundaries,to effectively address the complex challe

关键词： Coastal Chinese Mainland Runoff production Elastic analysis Climate change Anthropogenic interference

Efficient Environment-friendly Lead-free Tin Perovskite Solar Cells Enabled by Incorporating 4-Fluorobenzylammonium Iodide Additives

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Energy & Environmental Materials 2023年第6期6卷 318-326页

作者： Shengli zou Shengqiang Ren Yiting Jiang yuanfang Huang Wenwu Wang Changlei Wang Cong Chen Xia Hao Lili Wu Jingquan Zhang Dewei Zhao College of Materials Science and Engineering&Institute of New Energy and Low-Carbon Technology Sichuan UniversityEngineering Research Center of Alternative Energy Materials&DevicesMinistry of EducationChengdu 610065China School of Optoelectronic Science and Engineering&Collaborative Innovation Center of Suzhou Nano Science and Technology Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of ChinaSoochow UniversitySuzhou 215006China

Development of tin(Sn)-based perovskite solar cells(PSCs)largely lags behind that of lead counterparts due to fast crystallization process of Sn perovskite and numerous defects in both bulk and surface of Sn perovskite ***,this work reports a facile strategy of introducing 4-fluorobenzylammonium iodide(FBZAI)as additives into Sn perovskite precursor to synergistically modulate the roles of benzylamine and fluorine in Sn-based *** of FBZAI can increase crystallinity,passivate defects,and inhibit the oxidation of Sn^(2+),leading to suppression of nonradiative recombination and enhancement of charge transport and collection in *** a result,the best-performing Sn-based PSC with the FBZAI additive achieves the maximum PCE of 13.85%with the enhanced fill factor of 77.8%and open-circuit voltage of 0.778 *** unencapsulated device exhibits good stability by maintaining 95%of its initial PCE after 160 days of storage.

关键词： 4-fluorobenzylammonium iodide defect passivation lead-free Sn perovskites perovskite solar cells stability

Exciting lattice oxygen of nickel–iron bi-metal alkoxide for efficient electrochemical oxygen evolution reaction

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Journal of Energy Chemistry 2024年第1期88卷 194-201,I0005页

作者： Saihang Zhang Senchuan Huang Fengzhan Sun Yinghui Li Li Ren Hao Xu Zhao Li Yifei Liu Wei Li Lina Chong Jianxin zou National Engineering Research Center of Light Alloy Net Forming&State Key Laboratory of Metal Matrix Composites Center of Hydrogen ScienceSchool of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Laboratory of Advanced MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEM and State Key Laboratory of Molecular Engineering of PolymersCollege of Chemistry and MaterialsFudan UniversityShanghai 200433China

High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage *** electro-oxidation of water to oxygen plays a crucial role in such energy conversion ***,we report a robust method for the synthesis of a bimetallic alkoxide for efficient oxygen evolution reaction(OER)for alkaline electrolysis,which yields current density of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH *** catalyst demonstrates an excellent durability for more than 540 h operation with negligible degradation in *** spectra revealed that the catalyst underwent structure reconstruction during OER,evolving into oxyhydroxide,which was the active site proceeding OER in alkaline ***-situ synchrotron X-ray absorption experiment combined with density functional theory calculation suggests a lattice oxygen involved electrocatalytic reaction mechanism for the in-situ generated nickel–iron bimetal-oxyhydroxide *** mechanism together with the synergy between nickel and iron are responsible for the enhanced catalytic activity and *** findings provide promising strategies for the rational design of nonnoble metal OER catalysts.

关键词： Oxygen evolution reaction Nickel-iron bi-metal alkoxide Lattice oxygen-mediated reaction mechanism Alkaline electrolysis Electrocatalysts