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天文/惯性组合系统中重力扰动补偿方法

系统工程与电子技术 2024年第4期46卷 1357-1363页

作者：冷悦钟胜华中科技大学人工智能与自动化学院湖北武汉430074 多谱信息智能处理技术全国重点实验室湖北武汉430074 华中光电技术研究所武汉光电国家研究中心湖北武汉430223

针对重力扰动引起惯性水平基准姿态测量误差进而导致天文/惯性组合导航系统定位精度下降的问题,提出天文/惯性组合系统中的重力扰动补偿方法。首先,基于导航误差模型分析了影响天文/惯性组合导航系统定位精度的主要因素。其次,推导了重... 详细信息

针对重力扰动引起惯性水平基准姿态测量误差进而导致天文/惯性组合导航系统定位精度下降的问题,提出天文/惯性组合系统中的重力扰动补偿方法。首先,基于导航误差模型分析了影响天文/惯性组合导航系统定位精度的主要因素。其次,推导了重力扰动、惯性水平基准姿态测量误差与天文导航定位误差之间的传播机理。然后,研究了重力扰动建模与修正方法,并将重力扰动补偿方法应用于惯性水平基准的导航解算回路中,实现重力扰动的有效补偿。跑车试验结果表明,所提重力扰动补偿方法可以将天文/惯性组合导航系统中定位误差的振荡幅值由1.6 n mile降低至0.5 n mile。

关键词：天文导航系统惯性导航系统组合导航系统重力扰动

电碳市场背景下典型环境权益产品衔接互认机制及关键技术

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中国电机工程学报 2024年第7期44卷 2558-2577,I0005页

作者：尚楠陈政冷媛南方电网能源发展研究院有限责任公司广东省广州市510663

“碳达峰、碳中和”目标下,我国电力市场、碳市场、绿证市场等在产品属性、价格形成、治理监管等方面的联系日益密切,推动电碳市场背景下典型环境权益产品的联通互认,是推动实现不同市场体系之间充分融合、协同发展的关键桥梁和有力抓... 详细信息

“碳达峰、碳中和”目标下,我国电力市场、碳市场、绿证市场等在产品属性、价格形成、治理监管等方面的联系日益密切,推动电碳市场背景下典型环境权益产品的联通互认,是推动实现不同市场体系之间充分融合、协同发展的关键桥梁和有力抓手。目前,国内电碳环境权益产品尚未形成规范统一的概念定义,暂未出现电碳环境权益产品衔接互认的成熟案例,亦较为缺少密切相关的政策与市场机制设计。该文通过归纳分析国内外主流电碳环境权益产品特点及衔接互认经验,结合我国电力市场、碳市场等市场建设发展现状,剖析当前绿色电力证书、绿色电力消费、非水可再生能源(电力)消纳量、碳排放权、自愿减排量(Chinese certified emission reduction,CCER)等不同类型环境权益产品衔接互认过程中存在的碳排放量核算不准确、减排量重复认证、CCER申领范围不清晰等问题。该文在分析论述已有方案的同时,研究提出一种电碳市场背景下的不同类型环境权益产品的衔接互认体系,包括绿色电力消费与碳排放量的衔接、绿证或非水可再生能源(电力)消纳量与碳排放量的衔接、绿证与CCER的衔接等,并阐述支撑电碳环境权益产品衔接的4大类关键技术,为推动电、碳、绿证等多市场体系之间的协同发展提供决策参考。

关键词：电碳市场环境权益产品衔接互认机制碳排放量绿色电力消费碳排放因子

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High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si Zhong-Liang Li Wen-Hong Jia Lian Xue Hong-Xin Luo Jian-Cai Xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji Yu-Xin leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was *** result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet ***,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Toughening Mechanism of Large Heat Input Weld Metal for Marine Engineering Extra-Thick Plate

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Journal of Shanghai Jiaotong university(Science) 2024年第2期29卷 349-360页

作者：冷俊杰邸新杰利成宁程尚华 School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Advanced Joining Technology Tianjin 300350China Penglai Jutao Offshore Engineering Heavy Industry Co.Ltd. Yantai 265600ShandongChina

In order to study the latest designed large heat input welding material of marine engineering extra-thick plate,EH36 steel was joined by using twin-wire submerged arc welding with heat inputs of 85,100 and 115 kJ/cm ***,the microstructure and mechanical properties were evaluated to explore the toughening mechanism of weld *** show that a lot of active inclusions are obtained in the weld metal due to the design idea of low carbon and oxide metallurgy,which contributes to the generation of numerous fine and interlocking acicular *** acicular ferrite volume ratio of weld metal exceeds 60%.Moreover,the impact energy at-40℃ surpasses 115 J and the crack tip opening displacement value at-10℃ is more than 0.2 mm under three heat inputs owing to the role of acicular ferrite,of which 85 kJ/cm is the *** martensite-austenite constituents are minor in size and the microstructure of the weld metal in reheated zone is dominated by small massive equiaxed ferrite,without impairing the *** the heat input increases,the content of acicular ferrite drops and then rises;the impact toughness and fracture toughness first worsen consequently and then stabilize on account of the dramatic expansion of the proeutectoid ferrite size.

关键词： large heat input extra-thick plate weld metal acicular ferrite toughness

Ultrafast laser state active controlling based on anisotropic quasi-1D material

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Light(Science & Applications) 2024年第4期13卷 717-726页

作者： Zixin Yang Qiang Yu Jian Wu Haiqin Deng Yan Zhang Wenchao Wang Tianhao Xian Luyi Huang Junrong Zhang Shuai Yuan Jinyong leng Li Zhan Zongfu Jiang Junyong Wang Kai Zhang Pu Zhou College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China. Nanhu Laser Laboratory National University of Defense TechnologyChangsha 410073China. i-Lab&Key Laboratory of Nanodevices and Applications&Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China. School of Applied and Engineering Physics Cornell UniversityIthacaNY 14853USA. State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China. Shanghai Key Lab of Modern Optical System University of Shanghai for Science and TechnologyShanghai 200093China

Laser state active controlling is challenging under the influence of inherent loss and other nonlinear effects in ultrafast *** an extension of degree of freedom in optical devices based on low-dimensional materials may be a way ***,the anisotropic quasi-one-dimensional layered material Ta2PdS6 was utilized as a saturable absorber to modulate the nonlinear parameters effectively in an ultrafast system by polarization-dependent *** polarization-sensitive nonlinear optical response facilitates the Ta2PdS6-based mode-lock laser to sustain two types of laser states,i.e.,conventional soliton and noise-like *** laser state was switchable in the single fiber laser with a mechanism revealed by numerical *** coding was further demonstrated in this platform by employing the laser as a codable light *** work proposed an approach for ultrafast laser state active controlling with low-dimensional material,which offers a new avenue for constructing tunable on-fiber devices.

关键词： polarization fiber controlling

Brain-wide activation involved in 15 mA transcranial alternating current stimulation in patients with first-episode major depressive disorder

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General Psychiatry 2024年第2期37卷 265-273页

作者： Jie Wang Wenfeng Zhao Huang Wang Haixia leng Qing Xue Mao Peng Baoquan Min Xiukun Jin Liucen Tan Keming Gao Hongxing Wang Songjiang Hospital and Songjiang Research Institute Shanghai Key Laboratory of Emotions and Affective DisordersShanghai Jiao Tong University School of MedicineShanghaiChina Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyangHubeiChina Division of Neuropsychiatry and Psychosomatics Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina Electroconvulsive Therapy University Hospitals Cleveland Medical CenterClevelandOhioUSA Department of Psychiatry Case Western Reserve University School of MedicineClevelandOhioUSA Institute of Sleep and Consciousness Disorders Center of EpilepsyBeijing Institute for Brain DisordersCapital Medical UniversityBeijingChina Institute of Special Medical Sciences School of Forensic MedicineShanxi Medical UniversityTaiyuanShanxiChina

Background Although 15 mA transcranial alternating current stimulation(tACS)has a therapeutic effect on depression,the activations of brain structures in humans accounting for this tACS configuration remain largely *** To investigate which intracranial brain structures are engaged in the tACS at 77.5 Hz and 15 mA,delivered via the forehead and the mastoid electrodes in the human *** Actual human head models were built using the magnetic resonance imagings of eight outpatient volunteers with drug-naïve,first-episode major depressive disorder and then used to perform the electric field distributions with SimNIBS *** The electric field distributions of the sagittal,coronal and axial planes showed that the bilateral frontal lobes,bilateral temporal lobes,hippocampus,cingulate,hypothalamus,thalamus,amygdala,cerebellum and brainstem were visibly stimulated by the 15 mA tACS *** Brain-wide activation,including the cortex,subcortical structures,cerebellum and brainstem,is involved in the 15 mA tACS intervention for first-episode major depressive *** results indicate that the simultaneous involvement of multiple brain regions is a possible mechanism for its effectiveness in reducing depressive symptoms.

关键词： stimulation involvement activation

漯河市典型工业源挥发性有机物源成分谱特征及影响

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环境科学 2024年第8期45卷 4484-4492页

作者：杜宇彬吴丽萍牛大伟冷海斌薛爽张楠杨文中国环境科学研究院北京100012 天津城建大学环境与市政工程学院天津300384 漯河市环境监控中心漯河462000

选取漯河市10类典型工业企业开展有组织排放挥发性有机物(VOCs)样品采集,分析各行业VOCs排放特征及其影响.结果表明,包装印刷行业排放VOCs以OVOC(60.9%)为主;工业涂装行业VOCs排放以芳香烃(42.4%)和OVOC(38.9%)为主;制鞋、家具制造和造... 详细信息

选取漯河市10类典型工业企业开展有组织排放挥发性有机物(VOCs)样品采集,分析各行业VOCs排放特征及其影响.结果表明,包装印刷行业排放VOCs以OVOC(60.9%)为主;工业涂装行业VOCs排放以芳香烃(42.4%)和OVOC(38.9%)为主;制鞋、家具制造和造纸行业的VOCs排放特征相似,以OVOC(32.3%~42.6%)和芳香烃(20.7%~33.7%)为主,且卤代烃排放也不容忽视;化工和制药行业排放的VOCs中卤代烃占比最高,分别为59.3%和46.6%;砖瓦制品行业的VOCs排放以烷烃为主(62.7%);热力生产与供应行业的VOCs排放特征以OVOC(48.5%)为主,其次为卤代烃(19.7%);食品制造行业的VOCs排放则以OVOC(48.1%)和烷烃(29.4%)为主.不同行业的VOCs特征物种存在差异,但整体上,丙酮、异丙醇、苯、甲苯、间/对-二甲苯、乙烷、乙醛和二氯甲烷是漯河市多数行业VOCs排放的特征物种.漯河市典型工业有组织排放的VOCs对臭氧生成潜势贡献较大的组分以OVOC和芳香烃为主,对二次有机气溶胶生成潜势较大的组分为芳香烃.食品制造和家具制造行业排放的VOCs生成O_(3)的源活性因子[SR(O_(3))]较高,分别为3.7g·g^(-1)和3.5 g·g^(-1);工业涂装、家具制造和制鞋行业排放的VOCs生成二次有机气溶胶的源活性因子[SR(SOA)]较高,分别为0.021、0.017和0.014 g·g^(-1);基于PM_(2.5)和O_(3)协同管控视角,食品制造、工业涂装和家具制造是漯河市应当优先管控的行业,家具制造行业则是优控行业中的重中之重.

关键词：挥发性有机物(VOCs) 工业排放源成分谱臭氧生成潜势(OFP) 二次有机气溶胶生成潜势(SOAP)

Associations between residence and cognitive function among Chinese older adults: the mediating role of leisure activity

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Medical Data Mining 2024年第3期7卷 46-52页

作者： Xiao-Dong leng Wen-Ping Zeng Mao-Rui Qian School of Public Health Chongqing Medical UniversityChongqing 401331China

Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese *** study used leisure activities as a mediating variable to investigate the mediating role of leisure activity between place of residence(city-town-rural)and cognitive function among Chinese older,this is where the innovation of the article comes ***:Using cross-sectional data from the 2018 Chinese Longitudinal Healthy Longevity Survey,Pearson correlation analyses were employed to examine the relationships among various *** analyses were conducted using the SPSS PROCESS macro program,version 3.5,written by Hayes,to explore the mediating effects of leisure activity between place of residence and cognitive function in older ***:A total of 10955 older adults were included in this study,with a mean age of(84.23±11.57)*** them,2739(24.8%)lived in the city,3627(33.1%)in town,and 4615(42.1%)in rural areas;their leisure activity score was(5.34±3.77),and their cognitive function score was(24.69±6.65).Place of residence,leisure activities,and cognitive function were significantly correlated(P<0.01).Using city as a reference,place of residence is negatively associated with cognitive function,and place of residence not only had a direct effect on cognitive function in older adults:town-cognitive function(effect=–0.399;95%confidence interval(CI)=(–0.685,–0.113));rural-cognitive function(effect=–0.42;95%CI=(–0.698,–0.141)).There were also indirect effects on cognitive function through the pathway of leisure activity:town-leisure activity-cognitive function(effect=–0.17;95%CI=(–0.246,–0.1)),rural-leisure activity-cognitive function(effect=–0.199;95%CI=(–0.272,–0.13)).Conclusion:Leisure activities play a partially mediating role between the impact of place of residence and cognitive function in Chinese older adults,and it is vital to pay atte

关键词： residence leisure activity cognitive function intermediary role older adults

坝基缓坡预裂开挖中不同布孔方式下的爆破扰动比较分析

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岩土工程学报 2024年第5期46卷 1018-1029页

作者：高启栋张宸范勇周海孝卢文波冷振东长安大学公路学院陕西西安710064 三峡大学湖北省水电工程施工与管理重点实验室湖北宜昌443002 武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 中国葛洲坝集团易普力股份有限公司重庆401121

在坝基缓坡预裂开挖中,为解决传统主爆孔或缓冲孔顺坡布设时(称之为顺坡布孔)钻孔效率低的问题,工程建设者尝试采用了反坡钻孔的方式(称之为反坡布孔),有必要对两种布孔方式下坝基保留岩体扰动情况进行比较分析,以指导工程实践。依托白... 详细信息

在坝基缓坡预裂开挖中,为解决传统主爆孔或缓冲孔顺坡布设时(称之为顺坡布孔)钻孔效率低的问题,工程建设者尝试采用了反坡钻孔的方式(称之为反坡布孔),有必要对两种布孔方式下坝基保留岩体扰动情况进行比较分析,以指导工程实践。依托白鹤滩水电站坝基缓坡开挖,分别开展了顺坡布孔与反坡布孔两种开挖方式下的现场爆破试验,同时借助LS-DYNA三维动力有限元模拟,比较分析了两种布孔方式下保留岩体的爆破损伤演化特性与振动分布规律,并揭示了不同布孔方式下的内在力学作用机制,最后综合考虑开挖成型效果与施工速率,对坝基缓坡开挖方案的选择进行了探讨。结果表明:两种布孔方式下由预裂孔引起的保留岩体扰动情况基本一致,区别在于主爆孔或缓冲孔引起的累积损伤效应与爆破振动,内在原因在于炮孔与保留岩体轮廓面夹角的变化。相对顺坡布孔,反坡布孔因增大了主爆孔或缓冲孔与轮廓面的夹角,减少了传输至保留岩体的爆炸能量,有利于减轻对保留岩体的扰动,可减小损伤深度约11.6%~13.9%,降低爆破振动约6.4%~53.7%。

关键词：坝基缓坡预裂爆破顺坡布孔反坡布孔爆破扰动