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Extraction of line-of-sight ionospheric observables from GPS data using precise point positioning

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Science China Earth Sciences 2012年第11期55卷 1919-1928页

作者： ZHANG BaoCheng OU JiKun yuan YunBin LI ZiShen State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhan 430077China Graduate University of Chinese Academy of Sciences Beijing 100049China

Here we propose a method for extracting line-of-sight ionospheric observables from GPS data using precise point positioning(PPP).The PPP-derived ionospheric observables(PIOs) have identical form with their counterparts obtained from leveling the geometry-free GPS carrier-phase to code(leveling ionospheric observables,LIOs),and are affected by the satellite and receiver inter-frequency biases(IFBs).Based on the co-location experiments,the effects of extracting error arising from the observational noise and multipath on the PIOs and the LIOs are comparatively assessed,and the considerably reduced effects ranging from 70% to 75% on the PIOs with respect to the LIOs can be verified in our *** addition,based on 26 consecutive days' GPS observations from two international GNSS service(IGS) sites(COCO,daEJ) during disturbed ionosphere period,the extracted PIOs and LIOs are respectively used as the input of single-layer ionospheric model to retrieve daily satellite IFBs *** minor extracting errors underlying the PIOs in contrast to the LIOs can also be proven by reducing day-to-day scatter and improving between-receiver consistency in the retrieved satellite IFBs values.

关键词： line-of-sight ionospheric observables total electron content(TEC) precise point positioning(PPP) inter-frequency bias(IFB) extracting error

Propagation of crust deformation anomalies related to the Menyuan M_(S) 6.9 earthquake

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Earthquake Research Advances 2023年第4期3卷 43-48页

作者： Anfu Niu Chong Yue Zhengyi yuan Jing Zhao Wei Yan yuan Li China Earthquake Networks Center Beijing100045China The First Monitoring and Application Center Tianjin300180China

Decoding the variation laws of the deformation field before strong earthquakes has long been recognized as an essential issue in earthquake prediction research. In this paper, the temporal and spatial distribution characteristics of deformation anomalies in the northeastern margin of the Qinghai-Tibetan Plateau before and after the Menyuan M_(S)6.9 earthquake were studied by using the Fisher statistical test method. By analyzing the characteristics of these anomalies, we found that: 1) The deformation anomalies are mainly distributed in the marginal front area of the Qinghai-Tibetan Plateau, where short-term deformation anomalies are prone to occur due to a high gradient of gravity;2) The deformation anomalies along the northeastern margin of the Qinghai-Tibetan Plateau are characterized by spatial propagation, and the migration rate is about 2.4 km/d. The propagation pattern is counterclockwise, consistent with the migration direction of M_(S)≥ 6.0 earthquakes;3) The time and location of the Menyuan earthquake are related to the group migration of earthquakes with M_(S)≥ 6.0. Finally,based on the results of gravity field variation and the theory of crust stress wave, the law of deformation anomaly distribution was discussed. We suggest that both the deformation propagation along the northeastern margin of the Qinghai-Tibetan Plateau and the earthquake migration are possibly associated with the variation of the stress field caused by subsurface mass flow.

关键词： Northeastern margin of Qinghai-Tibetan Plateau Menyuan M_(S)6.9 earthquake Deformation propagation Earthquake migration Gravity field

Effect of acupuncture at three different acupoints on electrical activity of gastric distention-affected neurons in rat medial vestibular nucleus

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Journal of Traditional Chinese Medicine 2018年第1期38卷 125-131页

作者： Liang Chao Wang yuan Xu Bin Yu Zhi Department of Medicine Affiliated Hospital to Hebei University of Engineering Key Laboratory of Integrated Acupuncture and Drugs Affiliated to the Ministry of Education of China Nanjing University of Chinese Medicine Teaching Management Shandong Drug And Food Vocational College Key Laboratory of Integrated Acupuncture and Drugs Affiliated to the Ministry of Education of China Nanjing University of Chinese Medicine

OBJECTIVE: To observe the effect of gastric distention(GD) and acupuncture at three different acupoints on the spontaneous discharge of neurons in the medial vestibular nucleus(MVN), and to clarify the specific function of the MVN in the central integration mechanism underlying acupuncture ***: GD was conducted using a balloon inserted in the stomach cavity, and acupuncture was performed separately at each of three acupoints:Zusanli(ST 36), Quchi(LI 11), and Weishu(BL 21).The effect of acupuncture and GD on the spontaneous discharge of MVN neurons was assessed using a glass microelectrode filled with a sodium acetate electrolyte solution containing 1% pontamine sky blue; the discharge signals from the neurons were amplified by the microelectrode amplifier and recorded in the Spike2 ***: GD and acupuncture significantly affected the spontaneous discharge of MVN neurons. Furthermore, acupuncture at Zusanli(ST 36) and Weishu(BL 21) was significantly more effective at altering the discharge of GD-responsive MVN neurons compared with GD-nonresponsive ***: GD and acupuncture at three different acupoints affected the electrical activity of MVN neurons. The MVN is involved in the central integration mechanism underlying acupuncture regulation of gastric functions. The effects of acupuncture on gastric function may therefore be mediated via these particular MVN neurons.

关键词： Acupuncture Vestibular nuclei Motion sickness Electrical activity Spontaneous discharge Gastric distention

Novel directional comparison protection for distribution lines

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Science China(Technological Sciences) 2008年第4期51卷 353-361页

作者： DONG XinZhou yuan DingDing LU Qiang BO ZhiQian State Key Lab.of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China EAI AREVA Transimission&Distribution Ltd.StaffordUK 不详

For quickly clearing up a fault of distribution lines, which concerned with complex structure and operating modes, a directional comparison protection is necessary. The paper evaluated the traditional directional relay through modeling a typical distribution system and presented a novel negative sequence directional relay and a new directional comparison protection scheme specially designed for distribution systems. In the relay and the protection scheme, a particular negative sequence component has been constructed to solve the problem that there is no negative sequence component in a symmetrical fault case so that they could operate correctly in both asymmetrical fault and symmetrical fault. Extensive EMTP simulation studies proved that the protection schemes are able to provide fast and reliable responses for all fault conditions. In particular, they are able to give correct responses adapting to the change of system operation conditions, including the changing of system configuration, power flow direction, and source and tapped-offload conditions.

关键词： distribution lines negative sequence directional relay directional comparison protection

Expanding Views of Mitochondria in Parkinson's Disease: Focusing on PINK1 and GBA1 Mutations

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Neuroscience Bulletin 2022年第7期38卷 825-828页

作者： Yu yuan Xizhen Ma Ning Song Junxia Xie Institute of Brain Science and Disease School of Basic MedicineShandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological DisordersQingdao UniversityQingdao 266071China

A new conceptual model has been proposed for Parkinson's disease(PD)pathogenesis,which can be divided into triggering,facilitating,and aggravating processes[1].Mitochondria are believed to participate in all three pha... 详细信息

关键词： pathogenesis Mitochondria Focus

Fine Grained Feature Extraction Model of Riot-related Images Based on YOLOv5

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Computer Systems Science & Engineering 2023年第4期45卷 85-97页

作者： Shaofan Su Deyu yuan yuanxin Wang Meng Ding Department of Information Cyber Security People’s Public Security University of ChinaBeijing100038China Key Laboratory of Safety Precautions and Risk Assessment Ministry of Public SecurityBeijing102623China Public Security Behavioral Science Laboratory People’s Public Security University of ChinaBeijing102623China

With the rapid development of Internet technology,the type of information in the Internet is extremely complex,and a large number of riot contents containing bloody,violent and riotous components have *** contents pose a great threat to the network ecology and national *** a result,the importance of monitoring riotous Internet activity cannot be *** Neural Network(CNN-based)target detection algorithm has great potential in identifying rioters,so this paper focused on the use of improved backbone and optimization function of You Only Look Once v5(YOLOv5),and further optimization of hyperparameters using genetic algorithm to achieve fine-grained recognition of riot image ***,the fine-grained features of riot-related images were identified,and then the dataset was constructed by manual ***,the training and testing work was carried out on the constructed dedicated dataset by supervised deep learning *** research results have shown that the improved YOLOv5 network significantly improved the fine-grained feature extraction capability of riot-related images compared with the original YOLOv5 network structure,and the mean average precision(mAP)value was improved to ***,it provided strong support for combating riot-related organizations and maintaining the online ecological environment.

关键词： Convolutional neural network YOLOv5 riot-related fine grained target detection

Flow characteristic of polymer solutions in porous media:Influence of the molecular weight and concentration

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Petroleum 2023年第2期9卷 214-222页

作者： Yingjie dai Jia Li Li Li Yifei Liu yuan Li Xiangyu Wang Xuguang Song Caili dai Bin yuan Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum East China)Ministry of EducationQingdao 266580China Shandong Key Laboratory of Oilfield Chemistry(China University of Petroleum East China)Qingdao 266580China Nanchong Vocational and Technical College Nanchong 637131China Oil&Gas Technology Research Institute of Changqing Oilfield Company Xi'an 710000China Sinopec Research Institute of Petroleum Engineering Fracturing&Acidizing and Natural Gas Production Research InstituteDongying 257000China Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada

The polymer solution flow in porous media is a central research topic related to hydraulic fracturing measures,formation damage and fracture *** by molecular weights and concentrations,various flow patterns of polymer in pores are presented,resulting in different filtration *** this work,the effectiveness of various polymer solutions for filtration loss was assessed by utilizing the core flooding experiment *** result shows that lesser filtration loss normally is inextricably linked to solutions with high molecular weight and ***,the flow behaviors of polymer solutions investigated by designed micro pore-throat structure and micro-particle image velocimetry(m-PIV)further confirmed the above *** was found that the central convergent flow pattern benefiting from higher viscous force loss and less filtration loss was observed at high flow rates(0.5 mL/h),and higher molecular weight and concentration were more prone to convergent flow *** viscosity force loss increases by about 4 times varying the molecular weight of polymer from 5×10^(6)to 18×10^(6)g/mol or the concentration from 0.05 to 0.3%.It interprets higher molecular weight and concentration in core studies and field observations with decreased filtration loss of *** work provides a theoretical foundation for the application of fracturing fluids as well as fresh perspectives on how to access the filtration loss of fracturing fluids.

关键词： Polymer solution Porous media Flow pattern m-PIV

Paying less but harvesting more:the effect of unconscious acceptance in regulating frustrating emotion

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Science China(Life Sciences) 2015年第8期58卷 799-809页

作者： DING NanXiang YANG JieMin LIU YingYing yuan JiaJin Key Laboratory of Cognition and Personality Ministry of Education Faculty of Psychology Southwest University

Previous studies indicate that emotion regulation may occur unconsciously, without the cost of cognitive effort, while conscious acceptance may enhance negative experiences despite having potential long-term health benefits. Thus, it is important to overcome this weakness to boost the efficacy of the acceptance strategy in negative emotion regulation. As unconscious regulation occurs with little cost of cognitive resources, the current study hypothesizes that unconscious acceptance regulates the emotional consequence of negative events more effectively than does conscious acceptance. Subjects were randomly assigned to conscious acceptance, unconscious acceptance and no-regulation conditions. A frustrating arithmetic task was used to induce negative emotion. Emotional experiences were assessed on the Positive Affect and Negative Affect Scale while emotion-related physiological activation was assessed by heart-rate reactivity. Results showed that conscious acceptance had a significant negative affective consequence, which was absent during unconscious acceptance. That is, unconscious acceptance was linked with little reduction of positive affect during the experience of frustration, while this reduction was prominent in the control and conscious acceptance groups. Instructed, conscious acceptance resulted in a greater reduction of positive affect than found for the control group. In addition, both conscious and unconscious acceptance strategies significantly decreased emotion-related heart-rate activity(to a similar extent) in comparison with the control condition. Moreover, heart-rate reactivity was positively correlated with negative affect and negatively correlated with positive affect during the frustration phase relative to the baseline phase, in both the control and unconscious acceptance groups. Thus, unconscious acceptance not only reduces emotion-related physiological activity but also better protects mood stability compared with conscious acceptance. This su

关键词： unconscious acceptance emotion regulation frustration heart-rates positive affect negative affect

Short-lived AIM2 Inflammasome Activation Relates to Chronic MCMV Infection in BALB/c Mice

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Current Medical Science 2019年第6期39卷 899-905页

作者： yuan-yuan LU Xing-lou LIU yuan HUANG Yi LIAO Ting XI Ya-nan ZHANG Lin-lin ZHANG Sai-nan SHU Feng FANG Department of Pediatrics Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Absent in melanoma 2(AIM2)inflammasome is a crucial link bridging the innate host defense and the subsequent adaptive immunity when activated by exogenous double stranded DNA(dsDNA).Through establishing models of disseminated murine cytomegalovirus(MCMV)infection in BALB/c and C57BL/6 mice,we evaluated dynamic expression of AIM2 inflammasome components and its relationship with pathological damage and viral replication,trying tofigure out whether AIM2 inflammasome is related to the chronic mechanism of ***/c and C57BL/6 mice were sacrificed on day 0,1,3,7,14 and 28 post *** levels of AIM2,pro-caspase-1,caspase-1 p20,pro-IL1β and mature IL1β in primary peritoneal macrophages(PMs)and spleens were detected by Western *** of IL18 in the serum were detected by *** examinations of livers were performed,and mRNA levels of MCMV glycoprotein B(gB)in salivary glands also *** showed that expression levels of AIM2 in PMs and spleens of C57BL/6 mice increased on day 3,even continued to day 28;caspase-1 p20 and mature IL1β increased on day 7,14 and 28;the persistently high expression of IL1β in the serum started on day 1,showing a double peak *** for BALB/c mice,expression of AIM2 in PMs increased on day 1 and day 7,while contents of AIM2 in spleens increased on day 1 and day 3;caspase-1 p20 and mature ILip merely increased 7 days fter ***,expression levels of AIM2,caspase-1 p20,mature IL1β and IL18 were limited;the duration of AIM2 inflammasome activation in BALB/c mice was much shorter than that in C57BL/6 *** severer pathological damage and more viral replications in BALB/c mice further proved the deficient antiviral immunity to *** conclusion,the activation of AIM2 inflammasome in BALB/c mice was short-lived,which is quite possibly related to the chronicity of MCMV infection.

关键词： AIM2 murine cytomegalovirus BALB/c mice C57BL/6 mice macrophages