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Investigation on the Pointed Cocoon of Wild Silkworm Descendant
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作者 陈义安 张友洪 +5 位作者 王晓芬 刘彬斌 杜周和 刘俊凤 韩兵 胡春梅 《Agricultural Science & Technology》 CAS 2012年第1期217-219,226,共4页
[Objective] To study the cocoon traits of wild silkworm descendants. [Method] In the selective breeding of domesticated raising wild silkworm and wild silkworm descendants, investigation on the traits of the built coc... [Objective] To study the cocoon traits of wild silkworm descendants. [Method] In the selective breeding of domesticated raising wild silkworm and wild silkworm descendants, investigation on the traits of the built cocoons was carried out. [Result] The pointed traits of cocoons displayed obviously in the wild silkworm descendants, its pointed parts were consistent with the rear part of silkworm chrysalis, and the female silkworm has slight difference, indicating the silkworm co- coon pointed trait was hereditary. [Conclusion] This study provided references for the study of silkworm cocoon traits of wild silkworm descendant and guides the selective breeding of silkworm variety. 展开更多
关键词 Silkworm cocoon pointed Wild silkworm
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Study of Flow Field inside a Rectangular Air Intake with Pointed Cowl for Different Back Pressures at Mach 2.2
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作者 Shravan Koundinya Vutukuru Sudip Das Aleksandrs Urbahs 《World Journal of Engineering and Technology》 2018年第3期575-584,共10页
Computations and Experiments were performed to get an understanding of the flow field around a rectangular supersonic air intake with pointed cowl [90°] at different back pressures for Mach 2.2. The effect of Cow... Computations and Experiments were performed to get an understanding of the flow field around a rectangular supersonic air intake with pointed cowl [90°] at different back pressures for Mach 2.2. The effect of Cowl shape on the ramp surface pressure distribution is discussed and compared with existing V-Notch [90°] intake model at free exit condition. It was found that using pointed cowl [90°] intake model, a better pressure recovery was achieved compared to the V-Notch [90°] intake model at Mach 2.2. Both Pointed and V-Notch intake models showed good starting characteristics. For change in back pressure, the occurence of normal shock, flow separation zone and flow reversal were observed. All experiments are performed only for the Pointed cowl [90°] intake model. All the 3-D computations were performed by using software available at B.I.T, Mesra, Ranchi. 展开更多
关键词 Back Pressures COWL INTAKE MACH pointed [90°] COWL CLEAN COWL SCHLIEREN V-NOTCH [90°] COWL
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New CIIS President Appointed by Foreign Ministry
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《China International Studies》 2020年第6期F0002-F0002,共1页
On October 26,the Ministry of Foreign Affairs of China announced the appointment of Ambassador Xu Bu as the President of China Institute of International Studies(CIIS).Zheng Zeguang,Vice Minister of Foreign Affairs,at... On October 26,the Ministry of Foreign Affairs of China announced the appointment of Ambassador Xu Bu as the President of China Institute of International Studies(CIIS).Zheng Zeguang,Vice Minister of Foreign Affairs,attended the appointment ceremony and expressed his hope for Ambassador Xu to unite the CIIS leadership and staff under the guidance of the Foreign Ministry and elevate the top-level think tank to a new height. 展开更多
关键词 PRESIDENT pointed MINISTRY
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A Journey of Healing——Tracing the Beauty of Life in The Country of the Pointed Firs
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作者 WANG Ru 《海外英语》 2017年第17期167-169,共3页
There is an amazing healing power in the novel The Country of the Pointed Firs embodied in nature and the local people. Reading this novel, everyone can be the narrator who has experienced a journey of healing in Dunn... There is an amazing healing power in the novel The Country of the Pointed Firs embodied in nature and the local people. Reading this novel, everyone can be the narrator who has experienced a journey of healing in Dunnet Landing during her interactions with the coastal natural sceneries and the lovely local residents in that in those small islands. 展开更多
关键词 HEALING THOREAU NATURE WALDEN The Country of the pointed Firs
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Braided Extensions of a Pointed Fusion Category with Prime Dimension 被引量:3
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作者 Jingcheng Dong 《Algebra Colloquium》 SCIE CSCD 2020年第2期281-286,共6页
We obtain a necessary condition for a strictly weakly integral generalized Tambara-Yamagami fusion category to be braided.Then we use this result to classify braided extensions of a pointed fusion category with prime ... We obtain a necessary condition for a strictly weakly integral generalized Tambara-Yamagami fusion category to be braided.Then we use this result to classify braided extensions of a pointed fusion category with prime dimension. 展开更多
关键词 extension pointed fusion category Ising category
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A study of the pointed observation methods and sensitivity of HXMT 被引量:1
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作者 金晶 陈勇 +3 位作者 张双南 张澍 李新乔 李刚 《Chinese Physics C》 SCIE CAS CSCD 2010年第1期66-71,共6页
The Hard X-ray Modulation Telescope (HXMT) is an X-ray astronomy satellite consisting of three slat-collimated instruments, the High Energy X-ray Instrument (HE), the Medium Energy X-ray Instrument (ME), and the... The Hard X-ray Modulation Telescope (HXMT) is an X-ray astronomy satellite consisting of three slat-collimated instruments, the High Energy X-ray Instrument (HE), the Medium Energy X-ray Instrument (ME), and the Low Energy X-ray Instrument (LE). HXMT will carry out an all sky survey and make pointed observations in the 1-250 keV energy band. In order to get the source and background fluxes simultaneously in the pointed observations, two methods, i.e., the combined field of view (FOV) method and the off-axis pointing method are proposed in this paper. Comprehensive analyses of the sensitivities of the three instruments by using these two methods are presented, respectively. It is found that the off-axis pointing method has a higher sensitivity for HE and ME but a lower sensitivity for LE. Since the axes of the three instruments are aligned along the same direction, the off-axis pointing method is recommended as the main method in the pointed observation for HXMT; the combined FOV method can be used when LE is the most relevant instrument in order to satisfy the scientific objective of the observation. 展开更多
关键词 HXMT pointed observation sensitivity OFF-AXIS
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Pointed Representations of Virasoro Algebra 被引量:1
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作者 Xu Xiang (Department of Mathematics,Guangzhou Teacher’s College,Guangzhou 510000,China) 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1997年第2期161-168,共8页
In this paper we study the pointed representations of the Virasoro algebra.We show that unitary irreducible pointed representations of the Virasoro algebra are Harish-Chandra repre- sentations,thus they either are of ... In this paper we study the pointed representations of the Virasoro algebra.We show that unitary irreducible pointed representations of the Virasoro algebra are Harish-Chandra repre- sentations,thus they either are of highest or lowest weights or have all weight spaces of dimension 1.Further,we prove that unitary irreducible weight representations of Virasoro superalgebras are either of highest weights or of lowest weights,hence they are also Harish-Chandra representations. 展开更多
关键词 pointed representation Virasoro algebra Harish-Chandra representation VIRASORO
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PT-MFR:一种基于Point Transformer的CAD模型加工特征识别方法
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作者 何皓辰 方正 +2 位作者 卢政达 肖俊 王颖 《中国科学院大学学报(中英文)》 北大核心 2026年第1期115-124,共10页
加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不... 加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不足、加工特征定位不精准、实例分割过程复杂等挑战。针对这些问题,提出PT-MFR,一种基于Point Transformer的CAD模型加工特征识别方法,它执行语义分割和实例分割2个任务,分别预测模型每个面的加工特征语义类别并计算面相似度以分割加工特征实例,综合2个任务得到加工特征识别结果。实验结果表明,提出的方法性能优于现有的其他方法。 展开更多
关键词 加工特征识别 点云 神经网络 Point Transformer
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Pointed p^3-Dimensional Hopf Algebras in Positive Characteristic
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作者 Van C. Nguyen Xingting Wang 《Algebra Colloquium》 SCIE CSCD 2018年第3期399-436,共38页
We focus on the classification of pointed p^3-dimensional Hopf algebras H over any algebraically closed field of prime characteristic p 〉 0. In particular, we consider certain cases when the group of grouplike elemen... We focus on the classification of pointed p^3-dimensional Hopf algebras H over any algebraically closed field of prime characteristic p 〉 0. In particular, we consider certain cases when the group of grouplike elements is of order p or p^2 that is, when H is pointed but is not connected nor a group algebra. The structures of the associated graded algebra gr H are completely described as bosonizations of graded braided Hopf algebras over group algebras, and most of the lifting structures of H are given. This work provides many new examples of (parametrized) non-commutative, non-cocommutative finite- dimensional Hopf algebras in positive characteristic. 展开更多
关键词 braided Hopfalgebras Yetter-Drinfeld modules positive characteristic pointed Hopf algebras Nichols algebras
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Teichmüller spaces for pointed Fuchsian groups
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作者 SUN MingFeng SHEN YuLiang 《Science China Mathematics》 SCIE 2010年第8期2031-2038,共8页
Let T(G)be the Teichmüller space of a Fuchsian group G and T(G)be the pointed Teichmüller space of a corresponding pointed Fuchsian group G.We will discuss the existence of holomorphic sections of the projec... Let T(G)be the Teichmüller space of a Fuchsian group G and T(G)be the pointed Teichmüller space of a corresponding pointed Fuchsian group G.We will discuss the existence of holomorphic sections of the projection from the space M(G)of Beltrami coefficients for G to T(G)and of that from T(G)to T(G)as well.We will also study the biholomorphic isomorphisms between two pointed Teichmüller spaces. 展开更多
关键词 Fuchsian group pointed Fuchsian group Teichmüller space holomorphic section
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POINTED REPRESENTATIONS OFINFINITE DIMENSIONAL LIE ALGEBRAS
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作者 XUXIANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第2期255-260,共6页
A contravaried bilinear pairing X on every M(ρ) × M(ρθ) is determined and it is provedthat M(ρ)is irreducible if and only if K is left nondegellerate. It is also proved that every cyclicpointed module is a qu... A contravaried bilinear pairing X on every M(ρ) × M(ρθ) is determined and it is provedthat M(ρ)is irreducible if and only if K is left nondegellerate. It is also proved that every cyclicpointed module is a quotient of some Verma-like poillted module; moreover if it is irreduciblethen it is a quotieDt of the Vermarlike poiDted module by the left kernel of some bilinearpairing K. In case the mass fUnction is symmetric, there exists a bilinear form on M(ρ). It isproved that unitals pointed modules are integrable. In addition, a characterization of the massfunctions of Kac-Moody algebras is given, which is a generalization of the finite dimensionalLie algebras case. 展开更多
关键词 pointed representation Primitive cycle Mass function Bilinear pairing.
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Neuromodulation techniques for modulating cognitive function:Enhancing stimulation precision and intervention effects
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作者 Hanwen Cao Li Shang +9 位作者 Deheng Hu Jianbing Huang Yu Wang Ming Li Yilin Song Qianzi Yang Yan Luo Ying Wang Xinxia Cai Juntao Liu 《Neural Regeneration Research》 2026年第2期491-501,共11页
Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize... Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize electrical stimulation to directly or indirectly target specific brain regions,modulating neural activity and influencing broader brain networks,thereby regulating cognitive function.Regulating cognitive function involves an understanding of aspects such as perception,learning and memory,attention,spatial cognition,and physical function.To enhance the application of cognitive regulation in the general population,this paper reviews recent publications from the Web of Science to assess the advancements and challenges of invasive and non-invasive stimulation methods in modulating cognitive functions.This review covers various neuromodulation techniques for cognitive intervention,including deep brain stimulation,vagus nerve stimulation,and invasive methods using microelectrode arrays.The non-invasive techniques discussed include transcranial magnetic stimulation,transcranial direct current stimulation,transcranial alternating current stimulation,transcutaneous electrical acupoint stimulation,and time interference stimulation for activating deep targets.Invasive stimulation methods,which are ideal for studying the pathogenesis of neurological diseases,tend to cause greater trauma and have been less researched in the context of cognitive function regulation.Non-invasive methods,particularly newer transcranial stimulation techniques,are gentler and more appropriate for regulating cognitive functions in the general population.These include transcutaneous acupoint electrical stimulation using acupoints and time interference methods for activating deep targets.This paper also discusses current technical challenges and potential future breakthroughs in neuromodulation technology.It is recommended that neuromodulation techniques be combined with neural detection methods to better assess their effects and improve the accuracy of non-invasive neuromodulation.Additionally,researching closed-loop feedback neuromodulation methods is identified as a promising direction for future development. 展开更多
关键词 acupuncture points ATTENTION brain COGNITION efficiency electrical stimulation MICROELECTRODES movement disorders nervous system PERCEPTION
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Home,Sweet Home:A young returnee is breathing new life into a Chinese village-and finding purpose
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作者 ANTONY HARDI 《ChinAfrica》 2026年第2期28-30,共3页
History has never been driven by comfort,nor shaped solely by inheritance.Its most significant turning points have emerged from those with youth,conviction and courage ingrained in them.Progress starts when young peop... History has never been driven by comfort,nor shaped solely by inheritance.Its most significant turning points have emerged from those with youth,conviction and courage ingrained in them.Progress starts when young people not only dream but also take action.Sometimes,the boldest move is not to run towards the glow of cities,but to turn back-to one’s soil,roots and forgotten home-and help it to flourish. 展开更多
关键词 new life city glow historical turning points action CONVICTION Chinese village youth courage
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Storied Street,Fresh Faces
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作者 XIA YUANYUAN 《ChinAfrica》 2026年第3期31-33,共3页
Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street... Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street in Haikou,the capital of Hainan Province,served as the embarkation point for Hainanese setting out on their maritime voyages to seek greener pastures. 展开更多
关键词 OPENNESS international artists ENTREPRENEURS Haikou historical Qilou Street maritime voyages embarkation point Hainanprovince
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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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Process analysis of columnar dangerous rock mass collapse in the Three Gorges Reservoir Area based on 3D MPM
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作者 CHENG Shulou HUANG Bolin +3 位作者 ZHANG Peng LI Qiuwang DONG Xingchen Qin Panpan 《Journal of Mountain Science》 2026年第1期237-253,共17页
The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi ... The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi columnar dangerous rock mass(CCDRM)through field surveys and simulated its collapse dynamics with Material Point Method(MPM),and analyzed the collapse-diffusionsurge generation mechanisms.Field investigations revealed a 0.8 m-thick lotus-like extrusion structure at the base,severely degraded by cyclic water fluctuations,predisposing the rock mass to base-crushing failure.Numerical simulations indicate collapse velocities up to 42 m/s,amplified spreading with a 318 m deposition range and 11 m maximum thickness,and two major collisions causing 50%-60%velocity reduction.Gully topography buffers kinetic energy,retaining 5%debris on slopes and channeling 7%into the river.High-speed river impact generates a 20 m-diameter cavity,producing an 11 m surge,identifying the Guandukou Town waterfront 1.2 km downstream as a high-risk zone.These results clarify the collapse mechanisms of columnar dangerous rock mass and inform its hazard mitigation strategies. 展开更多
关键词 Dangerous rock mass Material Point Method Three-dimensional numerical simulation Disaster chain SURGE
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A Case of Severe Trauma with Iliac Vascular Injury was Treated using a Time-Based Chain Approach
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作者 Yazheng Shen Lining He +3 位作者 Huifeng Tang Zhiyong Shi Zhen He Ke Guo 《Journal of Clinical and Nursing Research》 2026年第1期380-386,共7页
Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based c... Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based chain rescue is crucial in managing severe trauma.A patient with chest and abdominal injuries and hemorrhagic shock was transferred from an ambulance to our hospital.Our trauma team-initiated pre-hospital first aid,utilized an emergency green channel,and conducted rapid ultrasound,collaborating across disciplines.The patient eventually recovered and was discharged. 展开更多
关键词 Severe trauma Hemorrhagic shock Time point of trauma Chain-type treatment
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Structural Reliability Analysis Based on Differential Evolution Algorithm and Hypersphere Integration
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作者 CHEN Zhenzhong HAN Zhuo +4 位作者 WANG Peiyu PAN Qianghua LI Xiaoke GAN Xuehui CHEN Ge 《Journal of Donghua University(English Edition)》 2026年第1期118-130,共13页
In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order relia... In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision. 展开更多
关键词 reliability analysis design point positioning differential evolution algorithm hypersphere integration
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Automated recognition of rock discontinuity in underground engineering using geometric feature analysis
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作者 Adili Rusuli Xiaojun Li +1 位作者 Yuyun Wang Yi Rui 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1016-1033,共18页
Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,su... Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes. 展开更多
关键词 Underground engineering Rock mass discontinuity Orientation grouping Fisher distribution 3D point cloud Automated recognition
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Modeling Liquid Loading Behavior in Coalbed Methane Gathering Pipelines
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作者 Yonghong Deng Ming Yang +8 位作者 Liqiong Chen Hongwei Rao Shengguang Li Changhui Zhou Yangyang Huang Zizheng Kong Xicheng Gao Chong Di Ting He 《Fluid Dynamics & Materials Processing》 2026年第2期158-178,共21页
With the maturation of coalbed methane(CBM)exploitation and the transition into the late stages of dewatering and gas production,liquid loading in gathering pipelines has emerged as a major constraint on productivity ... With the maturation of coalbed methane(CBM)exploitation and the transition into the late stages of dewatering and gas production,liquid loading in gathering pipelines has emerged as a major constraint on productivity and operational stability.Based on real-time field data and gas-liquid physicochemical analyses,this study elucidates the mechanisms governing liquid loading formation under varying temperature,pressure,and water saturation conditions.An HYSYS model is employed to determine the water dew point,while the Turner model is used to evaluate the critical conditions for liquid holdup.The results indicate that gas water saturation exerts the dominant influence on liquid loading risk,followed by pressure,whereas temperature plays a comparatively minor role.When water saturation exceeds 2%and the operating temperature falls below the dew point,condensation-driven liquid loading increases sharply.To further characterize the spatial distribution of liquid accumulation,a steady-state OLGA model of a DN100 gathering pipeline network is developed to examine the effects of pipe diameter,water saturation,and soil temperature.The simulations show that larger pipe diameters and higher water saturation significantly aggravate liquid holdup,while elevated soil temperature mitigates liquid accumulation.Moreover,the liquid holdup ratio is found to correlate closely with flow regime transitions,confirming its suitability as a key indicator of liquid loading risk.Based on these findings,optimization strategies for pipeline design and operation are proposed.To mitigate liquid loading,the gathering pipeline velocity should be maintained above the critical value of 1.63 m/s,and the gas water content should be strictly controlled below 2%.Under operating conditions representative of the Hancheng block,it is recommended to reduce the pipeline diameter from DN130 to DN100 to enhance self-cleaning capacity.In addition,thermal insulation should be applied during winter operation to maintain the pipe wall temperature above 10◦C,thereby suppressing condensation-induced liquid accumulation. 展开更多
关键词 Coalbed methane gathering pipeline network liquid loading mechanism water dew point OLGA numerical simulation
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