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Effect of orbital errors on the geosynchronous circular synthetic aperture radar imaging and interferometric processing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第5期12卷 404-416页

作者： Lei-lei kou Xiao-qing WANG Mao-sheng XIANG Jin-song CHONG Min-hui ZHU National Key Laboratory of Microwave Imaging Technology Institute of Electronics Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100190 China

The geosynchronous circular synthetic aperture radar (GEOCSAR) is an innovative SAR system,which can produce high resolution three-dimensional (3D) images and has the potential to provide 3D deformation *** an orbit altitude of approximately 36 000 km,the orbit motion and orbit disturbance effects of GEOCSAR behave differently from those of the conventional spaceborne *** this paper,we analyze the effects of orbit errors on GEOCSAR imaging and interferometric ***,we present the GEOCSAR imaging geometry and the orbit errors model based on perturbation ***,we give the GEOCSAR signal formulation based on imaging geometry,and analyze the effect of the orbit error on the output focused *** interferometric processing on the 3D reconstructed images,the relationship between satellite orbit errors and the interferometric phase is *** demonstrate the effects of orbit errors on the GEOCSAR images,interferograms,and the *** conclusions are that the required relative accuracy of orbit estimation should be at centimeter level for GEOCSAR imaging at L-band,and that millimeter-scale accuracy is needed for GEOCSAR interferometric processing.

关键词： Geosynchronous circular synthetic aperture radar (GEOCSAR) Orbit error Imaging Interferometric processing

Neural Attentional Relation Extraction with Dual Dependency Trees

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Journal of Computer Science & Technology 2022年第6期37卷 1369-1381页

作者： Dong Li Zhi-Lei Lei Bao-Yan song Wan-Ting Ji Yue kou School of Information Liaoning UniversityShenyang 110036China School of Computer Science and Engineering Northeastern UniversityShenyang 110004China

Relation extraction has been widely used to find semantic relations between entities from plain *** trees provide deeper semantic information for relation ***,existing dependency tree based models adopt pruning strategies that are too aggressive or conservative,leading to insufficient semantic information or excessive noise in relation extraction *** overcome this issue,we propose the Neural Attentional Relation Extraction Model with Dual Dependency Trees(called DDT-REM),which takes advantage of both the syntactic dependency tree and the semantic dependency tree to well capture syntactic features and semantic features,***,we first propose novel representation learning to capture the dependency relations from both syntax and ***,for the syntactic dependency tree,we propose a local-global attention mechanism to solve semantic *** design an extension of graph convolutional networks(GCNs)to perform relation extraction,which effectively improves the extraction *** conduct experimental studies based on three real-world *** with the traditional methods,our method improves the F 1 scores by 0.3,0.1 and 1.6 on three real-world datasets,respectively.

关键词： relation extraction graph convolutional network(GCN) syntactic dependency tree semantic dependency tree

Improvements on Calculation Model of Theoretical Combustion Temperature in a Blast Furnace

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Journal of Iron and Steel Research International 2011年第12期18卷 1-5页

作者： WU Sheng-li LIU Cheng-song FU Chang-liang XU Jian kou Ming-yin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

On the basis of the existing originally modified calculation models of theoretical combustion temperature（TCT）,some factors,such as the combustion ratio of pulverized coal injection（PCI）,the decomposition heat of PCI and the heat consumption of SiO2 in ash reduced in high temperature environment,were amended and improved to put forward a more comprehensive model for calculating *** influences of each improvement on TCT were studied and the results were analyzed compared with those of traditional model and originally modified model,which showed that the present model could reflect the thermal state of a hearth more effectively.

关键词： blast furnace theoretical combustion temperature improved calculation model

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海水淡化工艺排放浓海水中风险物质的识别

工业水处理 2024年第6期44卷 53-59,126页

作者：冯雪敏张晓青张爱君曹军瑞寇希元宋翰文邱金泉自然资源部天津海水淡化与综合利用研究所天津300192

基于海水淡化整个工艺流程,综述了浓海水中盐度、温度、原海水中的污染物、用于预处理的化学药品、淡化工艺过程中所需的药剂、化学品反应产生的副产物、腐蚀产物和过滤器反冲洗液等风险因素的引入过程及最终赋存情况,结合国内外风险物... 详细信息

基于海水淡化整个工艺流程,综述了浓海水中盐度、温度、原海水中的污染物、用于预处理的化学药品、淡化工艺过程中所需的药剂、化学品反应产生的副产物、腐蚀产物和过滤器反冲洗液等风险因素的引入过程及最终赋存情况,结合国内外风险物质危害阈值以及国外关于海洋生物的无影响浓度的预测结果,筛选和识别浓海水排放可能引入的具有潜在海洋环境影响的风险物质,结果表明,需要关注的风险物质包括铁盐,铝盐,丙烯酰胺,磷酸盐和总磷,余氯、总氯和消毒副产物,异噻唑啉酮,亚硫酸氢钠,还有重金属及类金属铜、镍、铬、钼、锌、铅、钛、镉、砷、硒、汞、钡。初步判定后还需进一步对风险物质进行实地验证性监测,更准确地掌握风险物质的浓度水平,以期更准确地评估浓海水排放的环境风险。

关键词：海水淡化浓海水环境影响重金属消毒副产物

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胎头吸引器复位新生儿颅骨大面积凹陷性骨折1例并文献复习

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临床神经外科杂志 2024年第4期21卷 477-480页

作者：李杰宋凯李汝珍叶庆寿寇军军陇南市第一人民医院神经外科陇南746000 陇南市第一人民医院产科陇南746000 陇南市第一人民医院新生儿科陇南746000

目的探讨胎头吸引器复位新生儿颅骨凹陷性骨折的治疗方法。方法回顾性分析陇南市第一人民医院2022年7月治疗的1例颅骨大面积凹陷性骨折新生儿的临床资料,并复习相关文献。结果新生儿,女性,经剖宫产娩出后随即发现颅骨大面积凹陷性骨... 详细信息

目的探讨胎头吸引器复位新生儿颅骨凹陷性骨折的治疗方法。方法回顾性分析陇南市第一人民医院2022年7月治疗的1例颅骨大面积凹陷性骨折新生儿的临床资料,并复习相关文献。结果新生儿,女性,经剖宫产娩出后随即发现颅骨大面积凹陷性骨折,10 h后经胎头吸引器负压吸引复位,术后复查复位良好,无明显并发症。结论胎头吸引器负压吸引治疗新生儿颅骨凹陷性骨折安全可靠,可为同类病例的治疗提供参考。

关键词：新生儿颅骨骨折吸引器

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血清miR-520e、miR-146a表达与老年HBV相关肝癌患者临床病理参数及预后的关系

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西部医学 2024年第9期36卷 1336-1340页

作者：马慧敏唐微许丹寇丹宋辉闫翔西部战区总医院干部二科一病区四川成都610083

目的探讨血清miR-520e、miR-146a表达与老年乙型肝炎病毒(HBV)相关肝癌患者临床病理参数及预后的关系。方法将2018年2月—2021年2月本院收治的HBV相关肝细胞癌患者95例设为观察组,将同期HBV患者100例设为对照组,采用实时聚合酶链反应法(... 详细信息

目的探讨血清miR-520e、miR-146a表达与老年乙型肝炎病毒(HBV)相关肝癌患者临床病理参数及预后的关系。方法将2018年2月—2021年2月本院收治的HBV相关肝细胞癌患者95例设为观察组,将同期HBV患者100例设为对照组,采用实时聚合酶链反应法(RT-PCR)检测两组血清中miR-520e和miR-146a水平。比较两组血清中miR-520e和miR-146a水平的差异,以及观察组中不同病理特征患者血清中miR-520e和miR-146a水平的差异,绘制不同miR-520e和miR-146a水平肝癌患者的1年无进展生存期生存曲线。结果观察组患者血清miR-520e、miR-146a水平均低于对照组患者(P<0.05);HCC患者中,病灶大小≥3 cm、有癌栓、伴淋巴结转移、TNM分期Ⅲ~Ⅳ期的患者血清miR-520e水平明显低于病灶大小<3 cm、无癌栓、不伴淋巴结转移、TNM分期Ⅰ~Ⅱ期的患者(P<0.05);HCC患者中,病灶大小≥3 cm、有癌栓、伴淋巴结转移、TNM分期Ⅲ~Ⅳ期的患者血清miR-146a水平明显低于病灶大小<3 cm、无癌栓、不伴淋巴结转移、TNM分期Ⅰ~Ⅱ期的患者(P<0.05);将观察组患者中miR-520e水平低于平均值患者分为低miR-520e表达组,高于平均值患者分为高miR-520e表达组;将观察组患者中miR-146a水平低于平均值患者分为低miR-146a表达组,高于平均值患者分为高miR-146a表达组。曲线分析结果显示,miR-520e和miR-146a高表达者1年内无进展生存期情况均明显优于低表达者(P<0.05)。结论HBV相关肝细胞癌患者中miR-520e和miR-146a血清水平显著低于HBV患者,且不同miR-520e和miR-146a血清水平的HBV相关肝细胞癌患者之间临床病理特征与预后存在显著差异。

关键词：乙型肝炎病毒肝细胞癌 miR-520e miR-146a 临床病理参数

Brain functional remodeling caused by sciatic nerve transposition repair in rats identified by multiplemodel resting-state blood oxygenation level-dependent functional magnetic resonance imaging analysis

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Neural Regeneration Research 2022年第2期17卷 418-426页

作者： Yu-song Yuan Hai-Lin Xu Zhong-Di Liu Yu-Hui kou Bo Jin Pei-Xun Zhang Department of Trauma and Orthopedics Peking University People’s HospitalPeking UniversityBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina National Center for Trauma Medicine BeijingChina

Lower extremity nerve transposition repair has become an important treatment strategy for peripheral nerve injury;however, brain changes caused by this surgical procedure remain unclear. In this study, the distal stump of the right sciatic nerve in a rat model of sciatic nerve injury was connected to the proximal end of the left sciatic nerve using a chitin conduit. Neuroelectrophysiological test showed that the right lower limb displayed nerve conduction, and the structure of myelinated nerve fibers recovered greatly. Muscle wet weight of the anterior tibialis and gastrocnemius recovered as well. Multiple-model resting-state blood oxygenation level-dependent functional magnetic resonance imaging analysis revealed functional remodeling in multiple brain regions and the re-establishment of motor and sensory functions through a new reflex arc. These findings suggest that sciatic nerve transposition repair induces brain functional remodeling. The study was approved by the Ethics Committee of Peking University People's Hospital on December 9, 2015(approval No. 2015-50).

关键词： brain connectivity brain network fALFF MRI nerve transposition repair peripheral nerve injury ReHo remodeling

Changes in proteins related to early nerve repair in a rat model of sciatic nerve injury

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Neural Regeneration Research 2021年第8期16卷 1622-1627页

作者： Yu-song Yuan Fei Yu Ya-Jun Zhang Su-Ping Niu Hai-Lin Xu Yu-Hui kou Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina National&Local Joint Engineering Research Center of Orthopedic Biomaterials Department of Bone&Joint SurgeryPeking University Shenzhen HospitalShenzhenGuangdong ProvinceChina National Center for Trauma Medicine BeijingChina Office of Academic Research Peking University People’s HospitalBeijingChina Diabetic Foot Treatment Center Peking University People’s HospitalBeijingChina

Peripheral nerves have a limited capacity for self-repair and those that are severely damaged or have significant defects are challenging to repair. Investigating the pathophysiology of peripheral nerve repair is important for the clinical treatment of peripheral nerve repair and regeneration. In this study, rat models of right sciatic nerve injury were established by a clamping method. Protein chip assay was performed to quantify the levels of neurotrophic, inflammation-related, chemotaxis-related and cell generation-related factors in the sciatic nerve within 7 days after injury. The results revealed that the expression levels of neurotrophic factors(ciliary neurotrophic factor) and inflammationrelated factors(intercellular cell adhesion molecule-1, interferon γ, interleukin-1α, interleukin-2, interleukin-4, interleukin-6, monocyte chemoattractant protein-1, prolactin R, receptor of advanced glycation end products and tumor necrosis factor-α), chemotaxis-related factors(cytokine-induced neutrophil chemoattractant-1, L-selectin and platelet-derived growth factor-AA) and cell generation-related factors(granulocyte-macrophage colony-stimulating factor) followed different trajectories. These findings will help clarify the pathophysiology of sciatic nerve injury repair and develop clinical treatments of peripheral nerve injury. This study was approved by the Ethics Committee of Peking University People's Hospital of China(approval No. 2015-50) on December 9, 2015.

关键词： animal model cell generation chemotaxis clamp injury inflammation injury neurotrophic factor peripheral nerve protein array repair sciatic nerve Wallerian degeneration

Accelerating matrix/boundary precipitations to explore high-strength and high-ductile Co_(34)Cr_(32)Ni_(27)Al_(3.5)Ti_(3.5) multicomponent alloys through hot extrusion and annealing

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Journal of Materials Science & Technology 2023年第12期143卷 62-83页

作者： Xiaoming Liu Zongde kou Ruitao Qu Weidong song Yijia Gu Changshan Zhou Qingwei Gao Jiyao Zhang Chongde Cao Kaikai song Vladislav Zadorozhnyy Zequn Zhang Jürgen Eckert Shenzhen Research Institute of Shandong University Shenzhen 518057China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China Department of Materials Science and Engineering Missouri University of Science and TechnologyRollaMO 65409USA Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China National University of Science and Technology«MISIS» Moscow 119049Russia Erich Schmid Institute of Materials Science Austrian Academy of SciencesLeoben A-8700Austria Department of Materials Science Montanuniversität LeobenLeoben A-8700Austria

Annealing-regulated precipitation strengthening combined with cold-working is one of the most efficient strategies for resolving the conflict between strength and ductility in metals and ***,precipitation control and grain refinement are mutually contradictory due to the excellent phase stability of multicomponent *** work utilizes the high-temperature extrusion and annealing to optimize the microstructures and mechanical properties of the Co_(34)Cr_(32)Ni_(27)Al_(3.5)Ti_(3.5) multicomponent *** extrusion effectively reduces grain sizes and simultaneously accelerates the precipitation of coherent L12 nanoparticles inside the face-centered cubic(FCC)matrix and grain boundary precipitations(i.e.,submicron Cr-rich particles and L12-Ni 3(Ti,Al)precipitates),resulting in strongly reciprocal interaction between dislocation slip and hierarchical-scale *** annealing regulates grain sizes,dislocations,twins,and precipitates,further allowing to tailor mechanical *** high yield strength is attributed to the coupled precipitation strengthening effects from nanoscale coherent L12 particles inside grains and submicron grain boundary precipitates under the support of pre-existing *** excellent ductility results from the synergistic activation of dislocations,stacking faults,and twins during plastic *** present study provides a promising approach for regulat-ing microstructures,especially defects,and enhancing the mechanical properties of multicomponent alloys.

关键词： Multicomponent alloys Hot extrusion Microstructure Mechanical properties Precipitation strengthening