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Combining orbital intensity modulated radiation therapy with periorbital triamcinolone acetonide injection for Graves’ orbitopathy
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作者 Huan Jian Rui-Xin Ma Wei-Min He 《International Journal of Ophthalmology(English edition)》 2025年第5期904-911,共8页
AIM:To evaluate the efficacy of combined orbital radiation and periorbital triamcinolone acetonide injection for patients with Graves’orbitopathy(GO)who experienced treatment failure with glucocorticoid pulse therapy... AIM:To evaluate the efficacy of combined orbital radiation and periorbital triamcinolone acetonide injection for patients with Graves’orbitopathy(GO)who experienced treatment failure with glucocorticoid pulse therapy(GPT).METHODS:A total of 57 eligible patients(35.09%males,mean age of 51.19±11.90y)were included in this case-series study.The medical information collected during each visit was evaluated and analyzed.RESULTS:Significant improvement was observed in patients six months after radiation therapy.Both the clinical activity score and the efficacy score showed substantial improvement(P<0.001).Furthermore,there was significant resolution of extraocular muscle inflammation on magnetic resonance imaging at three and six months after radiation therapy.The initial high signal intensity ratio(SIR)max was found to be associated with greater improvement in SIR sum(P<0.001,B=2.002,95%CI:1.377 to 2.628),while the presence of sight-threatening stage or moderate to severe diplopia negatively influenced the improvement of SIR sum(P=0.045,0.008,0.006;B=-1.966,-1.478,-0.997;95%CI:-3.886 to-0.045,-2.552 to-0.403,-1.694 to-0.300;respectively).CONCLUSION:The combination therapy demonstrates significant effectiveness in treating patients with GO who experienced severe ocular inflammation and have previous GPT failure.Noticeable improvement is observed as early as one month after initiating radiation therapy,and patients with more severe inflammatory states showes greater benefit from the treatment. 展开更多
关键词 Graves’orbitopathy thyroid ophthalmopathy orbital radiation periorbital injection glucocorticoid pulse therapy
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Bonding and anti-bonding orbitals stable electron intensity difference theory
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作者 Xiaobing Lan Hao Lu +5 位作者 Xusheng Wang Qing Li Dongdong Li Jun Chen Peng Wang Guangfu Liao 《Chinese Journal of Catalysis》 2025年第9期6-9,共4页
Surface chemistry plays a critical role in the fields of electrochemistry,heterogeneous catalysis,adsorption,etc.[1–4].The representative D-band center theory reported through Hammer and Nørskov in surface chemi... Surface chemistry plays a critical role in the fields of electrochemistry,heterogeneous catalysis,adsorption,etc.[1–4].The representative D-band center theory reported through Hammer and Nørskov in surface chemistry has been widely used in early studies to predict adsorption strength[5,6].Generally,the adsorption strength of active sites correlates inversely with the downward shift of the D-band center(εd)relative to the Fermi level,as lower-energy positioning increases anti-bonding orbital occupancy,weakening surface interactions(Fig.1(a)). 展开更多
关键词 anti bonding orbitals adsorption surface chemistry ELECTROCHEMISTRY heterogeneous catalysis electron intensity bonding orbitals electrochemistryheterogeneous catalysisadsorptionetc
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BDS-3 Satellite Orbit Prediction Method Based on Ensemble Learning and Neural Networks
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作者 Ruibo Wei Yao Kong +2 位作者 Mengzhao Li Feng Liu Fang Cheng 《Computers, Materials & Continua》 2025年第7期1507-1528,共22页
To address uncertainties in satellite orbit error prediction,this study proposes a novel ensemble learning-based orbit prediction method specifically designed for the BeiDou navigation satellite system(BDS).Building o... To address uncertainties in satellite orbit error prediction,this study proposes a novel ensemble learning-based orbit prediction method specifically designed for the BeiDou navigation satellite system(BDS).Building on ephemeris data and perturbation corrections,two new models are proposed:attention-enhanced BPNN(AEBP)and Transformer-ResNet-BiLSTM(TR-BiLSTM).These models effectively capture both local and global dependencies in satellite orbit data.To further enhance prediction accuracy and stability,the outputs of these two models were integrated using the gradient boosting decision tree(GBDT)ensemble learning method,which was optimized through a grid search.The main contribution of this approach is the synergistic combination of deep learning models and GBDT,which significantly improves both the accuracy and robustness of satellite orbit predictions.This model was validated using broadcast ephemeris data from the BDS-3 MEO and inclined geosynchronous orbit(IGSO)satellites.The results show that the proposed method achieves an error correction rate of 65.4%.This ensemble learning-based approach offers a highly effective solution for high-precision and stable satellite orbit predictions. 展开更多
关键词 BDS satellite orbit ensemble learning neural networks orbit error
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Orbital ATK公司高轨在轨服务卫星功能分析及启示
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作者 王彪 宋旭民 +1 位作者 王伟林 王少成 《航天器工程》 北大核心 2025年第2期113-119,共7页
诺斯罗普·格鲁曼创新系统公司(Orbital ATK,Inc.现)是高轨在轨服务卫星领域的重要公司,其技术演进路径具有重要研究价值。首先系统梳理Orbital ATK公司在不同阶段研发的高轨在轨服务卫星体系。然后对比分析各卫星相关技术功能,得... 诺斯罗普·格鲁曼创新系统公司(Orbital ATK,Inc.现)是高轨在轨服务卫星领域的重要公司,其技术演进路径具有重要研究价值。首先系统梳理Orbital ATK公司在不同阶段研发的高轨在轨服务卫星体系。然后对比分析各卫星相关技术功能,得出“微卫星技术试验”(MiTEx)、“局部空间自动导航与制导试验”(ANGEL)、“地球同步轨道空间态势感知计划”(GSSAP)等卫星在星上导航和态势感知技术上的发展脉络;“ESPA增强静止轨道实验室实验平台”(EAGLE)与“持久推进ESPA”(LDPE)系列卫星通过应用运载火箭次级有效载荷适配器(ESPA)环平台创新了"主星+多载荷"的模块化架构,形成载荷快速迭代更新能力;“任务扩展飞行器”(MEV)则开创了航天器延寿服务新范式。最后总结Orbital ATK公司卫星发展过程,对未来高轨在轨服务卫星的发展提出了启示。 展开更多
关键词 高轨卫星 orbital ATK公司:在轨服务 功能特点
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人工智能助力:Orbital Materials公司加速清洁技术材料的开发
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作者 燕春晖(摘译) 《石油炼制与化工》 北大核心 2025年第2期130-130,共1页
随着全球对环境保护意识的增强,探寻能够有效减少碳排放并促进可持续发展的新材料成为了科研领域的热点。一家成立于2022年的初创公司Orbital Materials,正利用人工智能(AI)技术在这一领域取得突破。
关键词 初创公司 清洁技术 orbitAL 环境保护意识 科研领域
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Spatial correlation singularities and orbital angular momentum spectra of partially coherent beams with noncanonical vortex pairs
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作者 MEI Chao CHENG Ke +2 位作者 YI Xiao-wen FU Cai-ying ZENG Ti-xian 《中国光学(中英文)》 北大核心 2025年第5期1243-1254,共12页
By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integra... By introducing noncanonical vortex pairs to partially coherent beams, spatial correlation singularity (SCS) and orbital angular momenta (OAM) of the resulting beams are studied using the Fraunhofer diffraction integral. The effect of noncanonical strength, off-axis distance and vortex sign on spatial correlation singularities in far field is stressed. Furthermore, far-field OAM spectra and densities are also investigated, and the OAM detection and crosstalk probabilities are discussed. The results show that the number of dislocations of SCS always equals the sum of absolute values of topological charges for canonical or noncanonical vortex pairs. Although the sum of the product of each OAM mode and its power weight equals the algebraic sum of topological charges for canonical vortex pairs, the relationship no longer holds in the noncanonical case except for opposite-charge vortex pairs. The changes of off-axis distance, noncanonical strength or coherence length can lead to a more dominant power in adjacent mode than that in center detection mode, which also indicates that crosstalk probabilities of adjacent modes exceed the center detection probability. This work may provide potential applications in OAM-based optical communication, imaging, sensing and computing. 展开更多
关键词 spatial correlation singularity orbital angular momentum noncanonical vortex partially coherent beam
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Dysplasia of extraocular muscles presenting as orbital space-occupying lesions–an extremely rare disorder
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作者 Shi-Yu Tang Xiang-Jun Wang +1 位作者 Meng-Ya Han Jian-Hua Yan 《International Journal of Ophthalmology(English edition)》 2025年第6期1090-1096,共7页
AIM:To describe the clinical manifestations,imaging features and surgical treatments in 5 cases of extraocular muscle(EOM)dysplasia presenting as orbital spaceoccupying lesions(SOL).METHODS:Records from the 5 cases wi... AIM:To describe the clinical manifestations,imaging features and surgical treatments in 5 cases of extraocular muscle(EOM)dysplasia presenting as orbital spaceoccupying lesions(SOL).METHODS:Records from the 5 cases with EOM dysplasia between 2004 and 2016 were retrospectively reviewed and clinical data were recorded including family history,age at onset,age at surgery,visual acuity,cycloplegic refraction,ocular alignment and motility,stereoacuity,exophthalmos,anterior segment and fundus,orbital computed tomography(CT)or magnetic resonance imaging(MRI)scan,surgical methods and final outcomes.RESULTS:All 5 cases(1 male,4 females)were unilateral(3 right,2 left eyes).The average age was 5.4y(range 4-6y)with no family history.Patients had unilateral strabismus(horizontal and vertical),restricted eye movement,and eyelid changes(abnormal fissures,lagophthalmos,and/or entropion)in the affected eye.None had proptosis;1 had 2-mm enophthalmos.Orbital CT/MRI showed irregular,ill-defined masses in EOM.Two anterior orbitotomies and 3 strabismus surgeries were performed,and pathology confirmed EOM dysplasia.After surgery,horizontal deviations,which ranged from exotropia(XT)10 prism diopter(PD)to esotropia(ET)10 PD(average 6 PD),decreased by an average of 18 PD,while vertical deviations,which ranged from 4 PD to 20 PD(mean 9.8 PD),decreased by an average of 23.2 PD.CONCLUSION:SOL from EOM dysplasia is non-familial and typically presenting unilaterally characterized by an irregular,diffusely infiltrating mass within the EOM.EOM involvement causes strabismus,restricted eye movement,eyelid changes,and enophthalmos likely due to cicatricial processes. 展开更多
关键词 extraocular muscle space-occupying lesion DYSPLASIA orbit STRABISMUS
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BRAKE ORBITS WITH MINIMAL PERIOD ESTIMATES OF FIRST-ORDER ANISOTROPIC HAMILTONIAN SYSTEMS
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作者 Xiaofei ZHANG Chungen LIU 《Acta Mathematica Scientia》 2025年第2期347-362,共16页
In this paper,the problem of brake orbits with minimal period estimates are considered for the first-order Hamiltonian systems with anisotropic growth,i.e.,the Hamiltonian functions may have super-quadratic,sub-quadra... In this paper,the problem of brake orbits with minimal period estimates are considered for the first-order Hamiltonian systems with anisotropic growth,i.e.,the Hamiltonian functions may have super-quadratic,sub-quadratic and quadratic behaviors simultaneously in different variable components. 展开更多
关键词 Hamiltonian system anisotropic growth brake orbit Lo-index
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Review of bumper materials for spacecraft shield against orbital debris hypervelocity impact
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作者 Siyuan Ren Pinliang Zhang +6 位作者 Qiang Wu Qingming Zhang Zizheng Gong Guangming Song Renrong Long Liangfei Gong Mingze Wu 《Defence Technology(防务技术)》 2025年第3期137-177,共41页
It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield design.This paper provides a comp... It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield design.This paper provides a comprehensive overview of advances in the development of bumper materials for spacecraft shield applications.In particular,the protective mechanism and process of the bumper using different materials against hypervelocity impact are reviewed and discussed.The advantages and disadvantages of each material used in shield were discussed,and the performance under hypervelocity impact was given according to the specific configuration.This review provides the useful reference and basis for researchers and engineers to create bumper materials for spacecraft shield applications,and the contemporary challenges and future directions for bumper materials for spacecraft shield were presented. 展开更多
关键词 orbital debris Spacecraft shield Hypervelocity impact Bumper materials Protective mechanism
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Enhancing p-d hybridization via synergistic regulation of spatial and energetic orbital overlaps in Ba-doped LaNiO_(3)epitaxial films for oxygen evolution activity
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作者 Yingjia Li Xiang Xu +11 位作者 Xiaoyu Qiu Jie Tu Zijian Chen Yujie Zhou Zhao Guan Youyuan Zhang Wen-Yi Tong Shaohui Xu Ni Zhong Pinghua Xiang Chun-Gang Duan Binbin Chen 《Chinese Physics B》 2025年第5期157-163,共7页
The hybridization between oxygen 2p and transition-metal 3d states largely determines the electronic structure near the Fermi level and related functionalities of transition-metal oxides(TMOs).Considerable efforts hav... The hybridization between oxygen 2p and transition-metal 3d states largely determines the electronic structure near the Fermi level and related functionalities of transition-metal oxides(TMOs).Considerable efforts have been made to manipulate the p-d hybridization in TMOs by tailoring the spatial orbital overlap via structural engineering.Here,we demonstrate enhanced p-d hybridization in Ba^(2+)-doped LaNiO_(3)epitaxial films by simultaneously modifying both the spatial and energetic overlaps between the O-2p and Ni-3d orbitals.Combining x-ray absorption spectroscopy and firstprinciples calculations,we reveal that the enhanced hybridization stems from the synergistic effects of a reduced chargetransfer energy due to hole injection and an increased spatial orbital overlap due to straightening of Ni-O-Ni bonds.We further show that the enhanced p-d hybridization can be utilized to promote the oxygen evolution activity of LaNiO_(3).This work sheds new insights into the fine-tuning of the electronic structures of TMOs for enhanced functionalities. 展开更多
关键词 transition-metal oxide doping p-d hybridization orbital overlap oxygen evolution activity
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Orbital to millennial scale dust activity and humidity interaction in Central Asia during the last glacial period
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作者 Haoru Wei Yougui Song +7 位作者 Shugang Kang Mingyu Zhang Mengping Xie Yanping Wang Li Han Shukhrat Shukurov Nosir Shukurov Fakhriddin Fayziev 《Geoscience Frontiers》 2025年第4期433-445,共13页
The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this st... The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this study,we established an optically stimulated luminescence chronology for the QSHA profile in the Yili Basin,a region influenced by westerlies.Grain size and trace element data were used as paleoclimatic indicators.We investigated the relationships among Central Asian dust activity,humidity,and westerlies strength on orbital to millennial scale from 37.4 ka to 11.6 ka.Our study reveals that,on orbital timescales,humidity is positively correlated with westerlies strength which controlled by precession.Dust activity is controlled by Siberian High which was regulated by Northern Hemisphere high-latitude temperature.Their responses to low-latitude and high-latitude forcing mechanisms respectively and present an opposite relationship.On millennial timescales,humidity and westerlies strength are positively correlated.During Marine Isotope Stage(MIS)2,humidity and dust activity show synchronous fluctuations,while during MIS 3,they exhibit an inverse relationship.Westerlies strength regulated humidity,which subsequently controlled glacial activity in the Tianshan Mountains,influencing dust activity in Central Asia.Additionally,the QSHA profile recorded seven Dansgaard-Oeschger(D-O)events on millennial timescales,indicating a potential link between Central Asian dust activity and high-latitude temperature variations in the Northern Hemisphere.Our findings provide new insights into dust and humidity interaction during the last glaciation periods in Central Asia and contribute to understanding global dust and hydrological cycles. 展开更多
关键词 Central Asian loess orbital timescale Millennial timescale Dust activity Humidity
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Guidelines for standard operation of imaging modalities in orbital diseases (2024)
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作者 Yi Shao Jian-Min Ma +5 位作者 Xiao-Ming Huang Expert Workgroup of Guidelines for the useof imaging equipment in orbital diseases(2024) Ophthalmic Imaging and IntelligentMedicine Branch Chinese Medicine Education Association Ocular Oncology Committee of theOphthalmology Branch of the Chinese Medical Doctor Association Ophthalmology Committee ofInternational Association of Translational Medicine Chinese Ophthalmic Imaging Study Groups 《International Journal of Ophthalmology(English edition)》 2025年第1期51-66,共16页
Orbital disorders include conditions originating from the orbital bones,surrounding tissues,and post-orbital septum.They also include systemic ailments affecting the orbit.Different clinical symptoms make up the compl... Orbital disorders include conditions originating from the orbital bones,surrounding tissues,and post-orbital septum.They also include systemic ailments affecting the orbit.Different clinical symptoms make up the complex range of orbital disorders.Because these disorders mostly impact the orbital area instead of the intraocular compartment,there is little diagnostic usefulness for typical ophthalmic visual tests.As such,the vital instruments for diagnosing and evaluating orbital illnesses have become ophthalmic imaging modalities,including ocular ultrasonography(B-scan),computed tomography(CT),and magnetic resonance imaging(MRI).One way to improve the precision and promptness of diagnosing orbital diseases is to standardize the functioning of widely used imaging equipment and define the radiological features of orbital abnormalities.Such programs are crucial for the care of patients with orbital disorders since they considerably reduce the number of misdiagnoses and missed diagnoses in these individuals.The underlying concepts,operational techniques,and normal and pathological imaging findings associated with common diagnostic tools for orbital illnesses are all thoroughly reviewed in this guideline.The objective is to improve primary healthcare settings’diagnostic competence in the field of orbital pathology and to standardize procedures for diagnosing orbital disorders. 展开更多
关键词 orbital disease ULTRASONOGRAPHY computed tomography magnetic resonance imaging standardized operation
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Effectively simplified Adriamycin-induced chronic kidney disease mouse model:Retro-orbital vein injection versus tail-vein injection
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作者 Masaki Watanabe Hayato R.Takimoto +2 位作者 Kazuki Hashimoto Yuki Ishii Nobuya Sasaki 《Animal Models and Experimental Medicine》 2025年第3期568-572,共5页
This study aimed to investigate the impact of administration routes in establishing the Adriamycin(ADR)-induced chronic kidney disease(CKD)model.Using BALB/c mice,we compared the effects of conventional tail-vein inje... This study aimed to investigate the impact of administration routes in establishing the Adriamycin(ADR)-induced chronic kidney disease(CKD)model.Using BALB/c mice,we compared the effects of conventional tail-vein injection(TV10,10 mg/kg)to those of retro-orbital sinus(orbital vein)injection(OV10,10 mg/kg;OV8,8 mg/kg).The re-sults indicated that the OV10 group exhibited CKD pathology similar to the TV10 group,with both groups demonstrating significantly higher urinary albumin/creatinine ratio(p<0.05),tubular injury(p<0.05),and degree of renal fibrosis(p<0.05)than the OV8 group.No significant differences were observed between the OV10 and TV10 groups in urinary albumin/creatinine ratio,tubular injury,and degree of renal fibrosis.These findings demonstrated that retro-orbital administration of 10 mg/kg ADR in-duces comparable effects to conventional tail-vein administration.This technique's technical simplicity may improve experimental efficiency,reproducibility,and animal welfare in CKD research.In conclusion,this study validates the utility of retro-orbital injection in CKD model establishment,demonstrating its potential to standardize and improve the reliability of future CKD research protocols. 展开更多
关键词 Adriamycin nephropathy BALB/c CKD orbital vein injection tail-vein injection
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Impulsive thrust strategy for orbital pursuit-evasion games based on impulse-like constraint
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作者 Hongbo WANG Yao ZHANG +1 位作者 Hao LIU Kunpeng ZHANG 《Chinese Journal of Aeronautics》 2025年第1期520-536,共17页
This paper proposes a novel impulsive thrust strategy guided by optimal continuous thrust strategy to address two-player orbital pursuit-evasion game under impulsive thrust control.The strategy seeks to enhance the in... This paper proposes a novel impulsive thrust strategy guided by optimal continuous thrust strategy to address two-player orbital pursuit-evasion game under impulsive thrust control.The strategy seeks to enhance the interpretability of impulsive thrust strategy by integrating it within the framework of differential game in traditional continuous systems.First,this paper introduces an impulse-like constraint,with periodical changes in thrust amplitude,to characterize the impulsive thrust control.Then,the game with the impulse-like constraint is converted into the two-point boundary value problem,which is solved by the combined shooting and deep learning method proposed in this paper.Deep learning and numerical optimization are employed to obtain the guesses for unknown terminal adjoint variables and the game terminal time.Subsequently,the accurate values are solved by the shooting method to yield the optimal continuous thrust strategy with the impulse-like constraint.Finally,the shooting method is iteratively employed at each impulse decision moment to derive the impulsive thrust strategy guided by the optimal continuous thrust strategy.Numerical examples demonstrate the convergence of the combined shooting and deep learning method,even if the strongly nonlinear impulse-like constraint is introduced.The effect of the impulsive thrust strategy guided by the optimal continuous thrust strategy is also discussed. 展开更多
关键词 orbital pursuit-evasion game Differential game Impulsive thrust Deep learning Shooting method
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Birkhoff Orbits for Twist Homeomorphisms on the High-Dimensional Cylinder
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作者 ZHOU Tong 《Wuhan University Journal of Natural Sciences》 2025年第1期43-48,共6页
It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cy... It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cylinder.By constructing a bounded solution of the monotone recurrence relation,the main conclusion in this paper is acquired:The induced homeomorphism has Birkhoff orbits provided there is a compact forward-invariant set.Therefore,it generalizes Angenent's results in low-dimensional cases. 展开更多
关键词 monotone recurrence relation twist homeomorphism high-dimensional cylinder bounded action Birkhoff orbit
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Spacecraft intelligent orbital game technology:A review
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作者 Xuyang CAO Xin NING +7 位作者 Suyi LIU Xiaobin LIAN Hongyan WANG Gaopeng ZHANG Feng CHEN Jiye ZHANG Bingzan LIU Zhansheng CHEN 《Chinese Journal of Aeronautics》 2025年第6期6-25,共20页
In recent years,the availability of space orbital resources has been declining,and the increasing frequency of spacecraft close approach events has heightened the urgency for enhanced space security measures.This pape... In recent years,the availability of space orbital resources has been declining,and the increasing frequency of spacecraft close approach events has heightened the urgency for enhanced space security measures.This paper establishes a comprehensive framework for intelligent orbital game technology in space,encompassing four core technologies:threat perception of noncooperative targets,intent recognition,situation assessment,and intelligent orbital game countermeasures.The concepts of multi-turn,multi-round and multi-match in space orbital games are defined,clarifying the core technological requirements for intelligent space orbital games and establishing a cohesive technological framework.Subsequently,the current status of research on these four core technologies is investigated.The challenges faced in the existing research are analyzed,and potential solutions for future studies are proposed.This paper aims to provide readers with a thorough understanding of the latest advancements in space intelligent orbital game technology.along with insights into the future directions and challenges in this field. 展开更多
关键词 Intelligent orbital game Threat perception Situation assessment Intent recognition Game confrontation
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Precision flatness measurement based on orbital angular momentum
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作者 Feifei Han Zhiwan Wang +1 位作者 Le Wang Shengmei Zhao 《Chinese Physics B》 2025年第5期415-422,共8页
We propose a method to measure the flatness of an object with a petal-like pattern generated by the interference of the measured orbital angular momentum(OAM)beam and the reference OAM beam which carries the opposite ... We propose a method to measure the flatness of an object with a petal-like pattern generated by the interference of the measured orbital angular momentum(OAM)beam and the reference OAM beam which carries the opposite OAM state.By calculating the difference between the petal rotation angle without/with the object,the thickness information of the object,and then the flatness information,can be evaluated.Furthermore,the direction of the object’s flatness can be determined by the petal’s clockwise/counterclockwise rotation.We theoretically analyze the relationship between the object’s thickness and petal rotation angle,and verify the proposed method by experiment.The experimental results show that the proposed method is a high precision flatness measurement and can obtain the convex/concave property of the flatness.For the 1.02 mm glass sample,the mean deviation of the flatness is 1.357×10^(-8) and the variance is 0.242×10^(-16).For the 0.50 mm glass sample,the mean deviation of the flatness is 1.931×10^(-8) and the variance is 2.405×10^(-16).Two different topological charges are adopted for the 2.00 mm glass sample,and their flatness deviations are 0.239×10^(-8)(ℓ=1)and 0.246×10^(-8)(ℓ=2),where their variances are 0.799×10^(-18)(ℓ=1)and 0.775×10^(-18)(ℓ=2),respectively.It is shown that the flatness measured by the proposed method is the same for the same sample when different topological charges are used.All results indicate that the proposed method may provide a high flatness measurement,and will be a promising way to measure the flatness. 展开更多
关键词 orbital angular momentum flatness measurement INTERFERENCE petal rotation angle
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A model predictive Stackelberg solution to orbital pursuit-evasion game
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作者 Yuchen LIU Chaoyong LI +1 位作者 Jun JIANG Yonghe ZHANG 《Chinese Journal of Aeronautics》 2025年第2期244-255,共12页
In this paper,we investigate analytical numerical iterative strategies for the pursuit-evasion game involving spacecraft with leader–follower information.In the proposed problem,the interplay between two spacecraft g... In this paper,we investigate analytical numerical iterative strategies for the pursuit-evasion game involving spacecraft with leader–follower information.In the proposed problem,the interplay between two spacecraft gives rise to a dynamic and real-time game,complicated further by the presence of perturbation.The primary challenge lies in crafting control strategies that are both efficient and applicable to real-time game problems within a nonlinear system.To overcome this challenge,we introduce the model prediction and iterative correction technique proposed in model predictive static programming,enabling the generation of strategies in analytical iterative form for nonlinear systems.Subsequently,we proceed by integrating this model predictive framework into a simplified Stackelberg equilibrium formulation,tailored to address the practical complexities of leader–follower pursuit-evasion scenarios.Simulation results validate the effectiveness and exceptional efficiency of the proposed solution within a receding horizon framework. 展开更多
关键词 Model predictive control Pursuit-evasion problem Leader-follower game Stackelberg game orbital game
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打破数据孤岛,数字化赋能绿色转型——访OrbitMI首席执行官Ali Riaz
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作者 薛龙玉 《中国船检》 2025年第2期26-28,共3页
近年来,航运业面临复杂多变的运营环境、日趋严格的法规要求以及不断增长的转型压力,如何借助数字化手段破局已成为关乎行业可持续发展的重要命题,布局数字化转型也成为许多航运企业适应行业变局的前瞻举措。几年前,瑞典油轮运营商Stena... 近年来,航运业面临复杂多变的运营环境、日趋严格的法规要求以及不断增长的转型压力,如何借助数字化手段破局已成为关乎行业可持续发展的重要命题,布局数字化转型也成为许多航运企业适应行业变局的前瞻举措。几年前,瑞典油轮运营商Stena Bulk投资了一系列数字化转型倡议,其中一个项目孵化出了运营平台“Orbit”,并很快与该公司的日常工作实现了无缝融合。2019年OrbitMI平台正式从Stena Bulk分拆出来,经过短短几年迅速发展,一跃成为海事软件领域的领航者。OrbitMI专注于解锁海事数据的潜藏价值,打造了集运营、财务及环境数据于一体的综合平台,并通过与业界重要相关方合作,不断巩固竞争优势。 展开更多
关键词 数字化转型 数据孤岛 绿色转型 综合平台 运营平台 orbit 环境数据 领航者
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Mode-switching cooperative defense strategy for the orbit pursuit-evasion-defense game
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作者 Yongshang Wei Tianxi Liu Cheng Wei 《Defence Technology(防务技术)》 2025年第2期272-286,共15页
This paper presents a mode-switching collaborative defense strategy for spacecraft pursuit-evasiondefense scenarios.In these scenarios,the pursuer tries to avoid the defender while capturing the evader,while the evade... This paper presents a mode-switching collaborative defense strategy for spacecraft pursuit-evasiondefense scenarios.In these scenarios,the pursuer tries to avoid the defender while capturing the evader,while the evader and defender form an alliance to prevent the pursuer from achieving its goal.First,the behavioral modes of the pursuer,including attack and avoidance modes,were established using differential game theory.These modes are then recognized by an interactive multiple model-matching algorithm(IMM),that uses several smooth variable structure filters to match the modes of the pursuer and update their probabilities in real time.Based on the linear-quadratic optimization theory,combined with the results of strategy identification,a two-way cooperative optimal strategy for the defender and evader is proposed,where the evader aids the defender to intercept the pursuer by performing luring maneuvers.Simulation results show that the interactive multi-model algorithm based on several smooth variable structure filters perform well in the strategy identification of the pursuer,and the cooperative defense strategy based on strategy identification has good interception performance when facing pursuers,who are able to flexibly adjust their game objectives. 展开更多
关键词 Cooperative policy Differential games orbit pursuit-evasion-defense game Mod recognition
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