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泥河湾盆地上新世-更新世过渡时期野火与植被和气候变化

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第四纪研究 2024年第1期44卷 16-28页

作者：张振赵永杰刘超飞丁国强李月丛河北地质大学地球科学学院河北石家庄050031 中国地质调查局第四纪年代学与水文环境演变重点实验室河北石家庄050061 河北师范大学汇华学院河北石家庄050091 河北师范大学地理科学学院河北石家庄050024 河北省环境演变与生态建设重点实验室河北石家庄050024 兰州大学资源环境学院西部环境教育部重点实验室兰州730000

上新世-更新世过渡时期是地球气候由相对温暖的上新世向第四纪冰期-间冰期旋回模式转变的重要阶段,也是现代气候和生态系统形成过程中的关键时期。野火作为地球生态系统重要的扰动因子,直接影响着地球生态环境结构和功能的演变,对维持... 详细信息

上新世-更新世过渡时期是地球气候由相对温暖的上新世向第四纪冰期-间冰期旋回模式转变的重要阶段,也是现代气候和生态系统形成过程中的关键时期。野火作为地球生态系统重要的扰动因子,直接影响着地球生态环境结构和功能的演变,对维持地球生态系统平衡具有重要作用。本研究通过对泥河湾盆地NHA钻孔(175.2~106.0 m段)上新世-更新世过渡时期(2.89~1.78 Ma)333个沉积物样品的炭屑分析,并结合孢粉分析结果,揭示了泥河湾盆地上新世-更新世过渡时期野火活动历史,探讨了研究段内泥河湾盆地野火活动对区域气候、植被变化的响应特征以及野火强度与火频率的关系。研究结果显示:1)泥河湾盆地上新世-更新世过渡时期野火强度总体可以分为1个火强度较大的时期(2.74~2.32 Ma)和2个火强度较小的时期(2.89~2.74 Ma和2.32~1.78 Ma);2)炭屑总浓度以及>125μm粗粒炭屑浓度均表现出显著的41 ka斜率周期,表明泥河湾盆地野火活动强度受高纬冰量驱动影响显著;3)可燃生物量是影响野火强度的最主要因素,而植被类型对野火强度的影响较小;4)火强度与火频率的变化不完全同步,表现为强度大-频率高、强度大-频率低以及强度小-频率高的3种模式;5)2.60~2.14 Ma是研究段泥河湾盆地野火活动最强的时期,表现为火强度大-频率高,该时期泥河湾盆地受全球气候变冷影响,植被以针叶林为主,生物量较大,气候波动频繁,野火活动强;6)强度大-频率高的火活动模式通常出现在气候转型期或古地磁漂移事件期间,在2.60~2.56 Ma、2.15~2.14 Ma以及1.82~1.78 Ma出现的火强度和火频率峰值分别对应于Matuyama/Gauss古地磁倒转时期、Reunion正极性漂移事件以及Olduvai正极性漂移事件中后期,可能与古地磁倒转引起的气候波动变化导致泥河湾盆地野火活动增强有关。

关键词：泥河湾盆地上新世-更新世过渡时期炭屑火强度火频率

The Orbital Modulation for the Spectrum and Mass Accretion Rate in Circinus X-1

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International Journal of Astronomy and Astrophysics 2012年第4期2卷 256-265页

作者： guoqiang ding Chunping Huang Jinlu Qu Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Beijing China Xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi China

Using the data from the Proportional Counter Array on board theRossi X-Ray Timing Explorersatellite, we study the orbital modulation for the spectrum and mass accretion rate of Cir X-1 during its two orbital periods. We use a model consisting of a blackbody, a multicolor disk blackbody, and a line component to fit the spectrum and find that the spectrum is obviously modulated by the orbital phase. It is shown that the disk accretion rate in Cir X-1 undergoes three states during the orbital period. At the periastron with orbital phase 0-0.1, the disk accretion rate is sup-Eddington, then from phase 0.1 to the apastron (phase 0.5) it decreases dramatically and becomes near-Eddington, and from the apastron to the next periastron (phase 1) the disk accretion rate approximates Eddington and tends to be steady. We argue that the evolution of the disk accretion rate is attributed to the high orbital eccentricity of this source. The mass accretion rate onto the neutron star is much less than that onto the inner disk, indicating significant outflows in this source.

关键词： Accretion Disk Compact Object Neutron Star Individual (Circinus X-1)

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3D导板技术在反肩关节置换中的应用

中华肩肘外科电子杂志 2024年第1期12卷 21-26页

作者：谢鹏丁国强郑翰魏有康刘晗卢冰成都中医药大学医学与生命科学学院 610075 四川省医学科学院四川省人民医院骨科成都610072

目的研究探讨3D导板技术在反肩关节置换中的应用效果。方法选取2020年10月至2022年10月本院收治的29例行反肩关节置换术患者为对象,随机数字表法分为观察组11例、对照组18例。观察组:男2例、女9例;年龄46~83岁,平均年龄(65.27±11.56)岁... 详细信息

目的研究探讨3D导板技术在反肩关节置换中的应用效果。方法选取2020年10月至2022年10月本院收治的29例行反肩关节置换术患者为对象,随机数字表法分为观察组11例、对照组18例。观察组:男2例、女9例;年龄46~83岁,平均年龄(65.27±11.56)岁;ASA分级:I级2例、II级5例、Ⅲ级3例、Ⅳ级1例;手术位置:左肩2例、右肩9例;原发疾病:肱骨粉碎性骨折5例、肱骨头坏死1例、肩关节骨性关节炎2例、肩袖型关节病3例。对照组:男6例、女12例;年龄52~80岁,平均年龄(65.00±9.99)岁;ASA分级:I级1例、II级12例、Ⅲ级5例;手术位置:左肩7例、右肩11例;原发疾病:肱骨粉碎性骨折12例、肩关节骨性关节炎3例、肩袖型关节病3例。组间一般资料比较差异无统计学意义(P>0.05)。观察组采用3D打印导板技术进行反肩关节置换术治疗,对照组行常规反肩关节置换术治疗。结果对两组患者手术进行情况、并发症发生率、肩关节活动功能评分、生活质量评分进行评估对比。观察组患者手术时间、术中出血量、开始下床活动时间均低于对照组(P0.05)。结论3D导板技术可以较好的应用在反肩关节置换中,能够减少手术时间、术中出血量,有利于患者早期下地,缓解疼痛,降低术后并发症发生率,改善患者的肩关节活动度。

关键词：反肩关节置换术 3D导板技术术中出血并发症发生率肩关节活动度生活质量

Modern pollen assemblages and their relationships with vegetation and climate on the northern slopes of the Tianshan Mountains, Xinjiang, China

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Journal of Arid Land 2023年第3期15卷 327-343页

作者： ZHANG Wensheng AN Chengbang LI Yuecong ZHANG Yong LU Chao LIU Luyu ZHANG Yanzhen ZHENG Liyuan LI Bing FU Yang ding guoqiang Key Laboratory of Western China's Environmental Systems Ministry of EducationCollege of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China College of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China

The reconstruction of paleovegetation and paleoclimate requires an understanding of the relationships between surface pollen assemblages and modern vegetation and climate.Here,we analyzed the characteristics of surface pollen assemblages across different vegetation zones in the Tianshan Mountains.Using surface pollen analysis and vegetation sample surveys at 75 sites on the northern slopes of the Tianshan Mountains,we determined the correlation between the percentage of dominant pollen types and the corresponding vegetation cover.Redundancy analysis was used to investigate the relationships between surface pollen assemblages and environmental factors.Our results show that the Tianshan Mountains contain several distinct ecological regions,which can be divided into five main vegetation zones from low to high altitudes:mountain desert zone(Hutubi County(HTB):500-1300 m;Qitai County(QT):1000-1600 m),mountain steppe zone(HTB:1400-1600 m;QT:1650-1800 m),mountain forest zone(HTB:1650-2525 m;QT:1850-2450 m),subalpine meadow zone(HTB:2550-2600 m;QT:2500-2600 m),and alpine mat vegetation zone(HTB:2625-2700 m;QT:2625-2750 m).The surface pollen assemblages of different vegetation zones can accurately reflect the characteristics of the mountainous vegetation patterns on the northern slopes of the Tianshan Mountains when excluding the widespread occurrence of Chenopodiaceae,Artemisia,and Picea pollen.Both average annual precipitation(P_(ann))and annual average temperature(T_(ann))affect the distribution of surface pollen assemblages.Moreover,P_(ann) is the primary environmental factor affecting surface pollen assemblages in this region.A significant correlation exists between the pollen percentage and vegetation cover of Picea,Chenopodiaceae,Artemisia,and Asteraceae.Moreover,Picea,Chenopodiaceae,and Artemisia pollen are over-represented compared with their corresponding vegetation cover.The Asteraceae pollen percentage roughly reflects the distribution of a species within the local vegetation.These results have important impli

关键词： surface pollen assemblages environmental factors vegetation cover redundancy analysis Tianshan Mountains

Simplification of the Plasma Load of Negative-Pulse-Bias Source Used in Arc Ion Plating

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Journal of Materials Science & Technology 2003年第Z1期19卷 97-98页

作者： Dong QI Ninghui WANG guoqiang LIN Zhenfeng ding Department of Electrical and Electronics Engineering Dalian University of Technology Dalian 116024 China Department of Electrical and Electronics Engineering Dalian University of Technology Dalian 116024 China State Key Laboratory for Materials Modification by Laser Ion and Electron Beams Dalian University of TechnologyDalian 116024 China State Key Laboratory for Materials Modification by Laser Ion and Electron Beams Dalian University of TechnologyDalian 116024 China

Based on the voltage and current fluctuating phenomenon in the arc plasma load under the negative-pulse-bias, usingthe plasma physics theory and analysis of computer simulation expatiates that the nature of plasma load in vacuumarc plasma is a capacitance load caused by plasma sheath and can be simplified as a parallel unit composed of acapacitor and a resistor, which have exact and quantitative description in the plasma physics theory. It concludes thevalues of capacitance and resistance are thousand PF and hundred ohm from the result of simulation and experiment.As a result, this has solved the key theoretical issues for the design of negative-pulse-bias source specifically used forvacuum arc ion plating.

关键词： Vacuum arc ion plating, Negative-pulse-bias, Plasma load

Panoptic UAV:Panoptic Segmentation of UAV Images for Marine Environment Monitoring

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工程与科学中的计算机建模(英文) 2024年第1期138卷 1001-1014页

作者： Yuling Dou Fengqin Yao Xiandong Wang Liang Qu Long Chen Zhiwei Xu Laihui ding Leon Bevan Bullock guoqiang Zhong Shengke Wang School of Computer Science and Technology Ocean University of ChinaQingdao266100China North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao266000China Department of Informatics University of LeicesterLeicesterLE17RHUK Research and Development Department Shandong Willand Intelligent Technology Co.Ltd.Qingdao266102China

UAV marine monitoring plays an essential role in marine environmental protection because of its flexibility and convenience,low cost and convenient maintenance.In marine environmental monitoring,the similarity between objects such as oil spill and sea surface,Spartina alterniflora and algae is high,and the effect of the general segmentation algorithm is poor,which brings new challenges to the segmentation of UAV marine images.Panoramic segmentation can do object detection and semantic segmentation at the same time,which can well solve the polymorphism problem of objects in UAV ocean images.Currently,there are few studies on UAV marine image recognition with panoptic segmentation.In addition,there are no publicly available panoptic segmentation datasets for UAV images.In this work,we collect and annotate UAV images to form a panoptic segmentation UAV dataset named UAV-OUC-SEG and propose a panoptic segmentation method named PanopticUAV.First,to deal with the large intraclass variability in scale,deformable convolution and CBAM attention mechanism are employed in the backbone to obtain more accurate features.Second,due to the complexity and diversity of marine images,boundary masks by the Laplacian operator equation from the ground truth are merged into feature maps to improve boundary segmentation precision.Experiments demonstrate the advantages of PanopticUAV beyond the most other advanced approaches on the UAV-OUC-SEG dataset.

关键词： Panoptic segmentation UAV marine monitoring attention mechanism boundary mask enhancement

Control of the Ultra-Low Frequency Oscillation in Southwest Power Grid of China Based on Damping Characteristic Analysis

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Control of the Ultra-Low Frequency Oscillation in Southwest ...

Analysis and Control to the Ultra-Low Frequency Oscillation in Southwest Power Grid of China: A Case Study

第37届中国控制会议

作者： Jiawei Wang Ancheng Xue Chao Zheng guoqiang ding Baisi Liu Xin Zhang Tianshu Bi State Key Laboratory of Alternate Electrical Power System with Renewable Energy Source North China Electric Power University China Electric Power Research Institute State Grid Southwest Power Control Center

At the end of 2018, the Southwest Power Grid will asynchronously interconnect with the State Grid, and the tests show that it exists a high proportion of ultra-low frequency oscillation（ULFO）, which threatening the operation of system. Based on the governor system model, the negative damping mechanism of ULFO is analyzed, and the suppression measure of adjusting the PI parameters of governor system is given. The details are as follows: in this paper, the phenomenon of ULFO in the Southwest Power Grid is introduced. And then based on detailed model, the mechanical damping coefficient of the governor system of each generator under the ultra-low frequency is calculated. The results show that the negative damping provided by hydro-turbine governor system is one of the main reasons causing the oscillation. Furthermore, the impact of PI parameters of governor system on the damping characteristics of hydropower generators is analyzed. Moreover, the idea to suppress ULFO based on adjusting the PI parameters is given, together with the considering for the influence of parameters on the transient and steady-state characteristics. Finally, simulation results show that the proposed PI parameters adjusting method to governor system could suppress the ULFO.

关键词： Ultra-low frequency oscillation governor system mechanical damping coefficient suppression measure

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Analysis and Control to the Ultra-Low Frequency Oscillation ...

Analysis of Ultra-Low Frequency Oscillation in Southwest Power Grid Based on Measurement Data

第30届中国控制与决策会议

作者： Chao Zheng guoqiang ding Baisi Liu Xin Zhang Jiawei Wang Ancheng Xue Tianshu Bi China Electric Power Research Institute State Key Laboratory of Alternate Electrical Power System with Renewable Energy Source North China Electric Power University State Grid Southwest Power Control Center

The ultra-low frequency oscillations（ULFO） are found in the future Southwest Power Grid under some faults, which will asynchronously interconnect with the State Grid via the HVDC and VSC-HVDC before the end of 2018. In this paper, the phenomenon of ULFO in the asynchronous interconnected Southwest Power Grid is introduced. And then, with the oscillation energy flow and the amplitude-phase analysis for the ULFO, the energy characteristics of each power plant participating in ULFO are revealed, i.e., the ULFO are mainly between the hydropower plants and the thermal power plants. Furthermore, with the analysis of damping characteristics of main hydropower plants, the cause of the ULFO, i.e., lacking of damping in the hydropower plant is revealed. Upon the above results, an example of suppressing the ULFO with the approach of control parameters tuning for the governor of the dominant generators is presented.

关键词： Asynchronous interconnection Ultra-low frequency oscillation Governor Oscillation energy Phase

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Analysis of Ultra-Low Frequency Oscillation in Southwest Pow...