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Multi-Objective Loosely Synchronized Search for Multi-Objective Multi-Agent Path Finding with Asynchronous Actions
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作者 DU Haikuo GUO Zhengyu +1 位作者 ZHANG Lulu CAI Yunze 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第4期667-677,共11页
In recent years,the path planning for multi-agent technology has gradually matured,and has made breakthrough progress.The main difficulties in path planning for multi-agent are large state space,long algorithm running... In recent years,the path planning for multi-agent technology has gradually matured,and has made breakthrough progress.The main difficulties in path planning for multi-agent are large state space,long algorithm running time,multiple optimization objectives,and asynchronous action of multiple agents.To solve the above problems,this paper first introduces the main problem of the research:multi-objective multi-agent path finding with asynchronous action,and proposes the algorithm framework of multi-objective loose synchronous(MO-LS)search.By combining A*and M*,MO-LS-A*and MO-LS-M*algorithms are respectively proposed.The completeness and optimality of the algorithm are proved,and a series of comparative experiments are designed to analyze the factors affecting the performance of the algorithm,verifying that the proposed MO-LS-M*algorithm has certain advantages. 展开更多
关键词 multi-agent path finding multi-objective path planning asynchronous action loosely synchronous search
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New Direction For China’s Economy in 2025 China will adopt a more proactive fiscal policy and a moderately loose monetary policy
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作者 Dai Bin Luo Weijie 《China Report ASEAN》 2025年第2期18-21,共4页
In 2024,China’s economy gradually trended towards recovery from the COVID-19 pandemic.According to official data released by the National Bureau of Statistics on January 17,preliminary estimates show China’s gross d... In 2024,China’s economy gradually trended towards recovery from the COVID-19 pandemic.According to official data released by the National Bureau of Statistics on January 17,preliminary estimates show China’s gross domestic product(GDP)at nearly 134 trillion yuan(US$18.7 trillion)in 2024,an increase of 5.0 percent over the previous year at constant prices. 展开更多
关键词 POLICY loosE adopt
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Collaborative movement characteristics of overlying rock and loose layer based on block–particle discrete‑element simulation method
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作者 Zhaopeng Ren Cun Zhang +2 位作者 Yongle Wang Shengli Yang Quansheng Li 《International Journal of Coal Science & Technology》 2025年第2期1-20,共20页
A novel block–particle discrete-element simulation method that matches the double medium of overlying rock(OLR)and loose layer(LSL)in coal mining is developed in this study.This method achieves the collaborative fail... A novel block–particle discrete-element simulation method that matches the double medium of overlying rock(OLR)and loose layer(LSL)in coal mining is developed in this study.This method achieves the collaborative failure characteristics of mining damage under the conduction of double media between the OLR and LSL by combining the self-weight stress loading of the LSL and the breakage morphology of the bedrock top.Based on this,the conduction law of high-strength mining damage in the double medium in a western mining area is simulated and analyzed.The combining effect of the OLR breakage morphology and LSL characteristics on the surface-subsidence characteristics is analyzed and verified based on on-site measurements.The results indicate that the OLR is guided by the“double-control layer and thick-soft rock buffer layer”and shows“grouping subsidence”,whereas the surface forms collaborative subsidence with the thick-soft rock buffer layer.In the ultra-full mining stage,the surface presents an“asymmetric inverted trapezoidal”subsidence trough shape.The simulation results agree well the on-site measurements in terms of the surface-subsidence and bedrock-subsidence coefficients.The proposed simulation method provides a scientific approach for investigating the micro-conduction mechanism of mining damage under the effect of high-strength mining in western mining areas.It will benefit future investigations pertaining to the characteristics of OLR breakage and surface subsidence under conditions such as LSL thickness and proportion. 展开更多
关键词 Extra-large mining height Overlying rock loose layer Double medium Discrete-element simulation Collaborative movement
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Experimental investigation on the stability of shield tunnel excavation face in upper loose and lower dense water-rich strata
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作者 Pengfei LI Chuang WANG +3 位作者 Xiaopu CUI Qing XU Zhaoguo GE Shaohua LI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期471-491,共21页
Maintaining the stability of the excavation face is key for ensuring the safety of underwater shield tunnel construction.However,the majority of current studies on the stability of excavation face focus on the homogen... Maintaining the stability of the excavation face is key for ensuring the safety of underwater shield tunnel construction.However,the majority of current studies on the stability of excavation face focus on the homogeneous strata,with limited research conducted on the upper loose and lower dense strata.Active instability tests are conducted in this study,in concert with the digital image correlation(DIC)technique,to investigate the effects of different water pressure ratios in upper loose and lower dense water-rich strata.The accuracy of these model tests is verified using numerical simulations.The results indicate that as water pressure ratio decreases,there is an increase in both the peak displacement of surface settlement and the seepage path range of water ahead of the excavation face expands.In contrast,decreasing water pressure ratio will break the limit equilibrium state of the strata faster,cause the earth pressure on the cutterhead to change more rapidly,and increase the instability range of the strata. 展开更多
关键词 Shield tunnel Upper loose and lower dense strata Excavation face stability Water pressure ratio
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Nonlinear Vibration of A Loosely Supported Curved Pipe Conveying Pulsating Fluid under Principal Parametric Resonance 被引量:6
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作者 Yangyang Luo Min Tang +2 位作者 Qiao Ni Yikun Wang Lin Wang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2016年第5期468-478,共11页
In this paper,the nonlinear dynamics of a curved pipe is investigated in the case of principal parametric resonance due to pulsating flow and impact with loose supports.The coupled in-plane and out-of-plane governing ... In this paper,the nonlinear dynamics of a curved pipe is investigated in the case of principal parametric resonance due to pulsating flow and impact with loose supports.The coupled in-plane and out-of-plane governing equations with the consideration of von Karman geometric nonUnearity are presented and discretized via the differential quadrature method(DQM).The nonlinear dynamic responses are calculated numerically to demonstrate the influence of pulsating frequency.Finally,the impact is taken into consideration.The influence of clearance on frettingwear damage,such as normal work rate,contact ratio and impact force level,is demonstrated. 展开更多
关键词 curved governing quadrature clearance Karman numerically loose conveying parametric dynamical
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Decay Analysis of Ge Isotopes Formed in Reactions Induced by Tightly and Loosely Bound Projectiles
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作者 Amandeep Kaur Kirandeep Sandhu Manoj K.Sharma 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第11期565-577,共13页
The dynamical cluster-decay model (DCM) is employed to investigate the decay of ^(6870)Ge~* compound nuclei formed respectively via tightly (~4He) and loosely (~6He) bound projectiles, using ^(64)Zn target. The study ... The dynamical cluster-decay model (DCM) is employed to investigate the decay of ^(6870)Ge~* compound nuclei formed respectively via tightly (~4He) and loosely (~6He) bound projectiles, using ^(64)Zn target. The study is carried out over a wide energy range (E_(c.m.)~5 MeV to 16 MeV) by including the quadrupole deformations (β_(2i)) and optimum orientations (θ_i^(opt)) of the decaying fragments. The fusion cross-sections, obtained by adding various evaporation channels show nice agreement with the experimental data for ~4He+^(64)Zn reaction. The contribution from competing compound inelastic scattering channel is also analyzed particularly for ^(68)Ge~* nucleus at above barrier energies. On the other hand,the decrement in the fusion cross-sections of ^(70)Ge~* nuclear system is addressed by presuming that ^(65)Zn ER is formed via two different modes:(i) the αn evaporation of ^(70Ge)~* nucleus, and(ii) 1n-evaporation of ^(66)Zn~*nuclear system,formed via breakup and 2n-transfer channels due to halo structure of the ~6He projectile. Besides this, the suppression in2 np evaporation cross-sections suggests the contribution of another breakup and transfer process of ~6He i.e. ~4He+ ^(64)Zn.The contribution of breakup+transfer channels for ~6He+^(64)Zn reaction is duly addressed by applying relevant energy corrections due to the breakup of "~6He" projectile into 2n and ~4He. In addition to this, the barrier lowering, angular momentum and energy dependence effects are also explored in view of the dynamics of chosen reactions. 展开更多
关键词 tightly and loosely BOUND PROJECTILES EVAPORATION RESIDUE BREAKUP and transfer
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Wave Hindcast for the Neighbouring Seas of Korea Based on Loosely Coupled Wave-Tide-Surge Model
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作者 CHOIByung-Ho EUMHyun-Min JEONSang-Soo 《China Ocean Engineering》 SCIE EI 2002年第2期165-181,共17页
A hindcast simulation of 75 typhoons and winter monsoons which affected the coastal areas of Korean Peninsula is performed by use of a third generation ocean wave prediction model, WAM-cycle 4 model, loosely coupled w... A hindcast simulation of 75 typhoons and winter monsoons which affected the coastal areas of Korean Peninsula is performed by use of a third generation ocean wave prediction model, WAM-cycle 4 model, loosely coupled with a com-bined tide and surge model. Typhoon wind fields are derived from the planetary marine boundary layer model for effective neutral winds embedding the vortical storm wind from the parameterized Rankin vortex type model in the limited areas of the overall modeled region. The hindcasted results illustrate that significant wave heights (SWH) considering the wave-tide-surge coupled process are significantly different from the results via the decoupled case especially in the region of the estuaries of the Changjiang Estuary, The Hangzhou Bay, and the southwestern tip of Korean Peninsula. This extensive model simulation is the first attempt to investigate the strong wave-tide-surge interaction for the shallow depth area along the coasts of the Yellow Sea and the East China Sea Continental shelf. 展开更多
关键词 wave hindcast mave-tide-surge process loosely coupled model significant wave height
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Stability analysis of loose accumulation slopes under rainfall:case study of a high‑speed railway in Southwest China 被引量:1
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作者 Xin Wang Qian Su +2 位作者 Zongyu Zhang Feihu Huang Chenfang He 《Railway Engineering Science》 EI 2024年第1期95-106,共12页
The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce... The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce adverse geological disasters under rainfall conditions.To ensure the smooth construction of the high-speed railway and the subsequent safe operation,it is necessary to master the stability evolution process of the loose accumulation slope under rainfall.This article simulates rainfall using the finite element analysis software’s hydromechanical coupling module.The slope stability under various rainfall situations is calculated and analysed based on the strength reduction method.To validate the simulation results,a field monitoring system is established to study the deformation characteristics of the slope under rainfall.The results show that rainfall duration is the key factor affecting slope stability.Given a constant amount of rainfall,the stability of the slope decreases with increasing duration of rainfall.Moreover,when the amount and duration of rainfall are constant,continuous rainfall has a greater impact on slope stability than intermittent rainfall.The setting of the field retaining structures has a significant role in improving slope stability.The field monitoring data show that the slope is in the initial deformation stage and has good stability,which verifies the rationality of the numerical simulation method.The research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system. 展开更多
关键词 High-speed railway loose accumulation slope Slope stability analysis Rainfall effect Strength reduction
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A Loosely Coupled Control Architecture Based on Agent and CORBA for Multiple Robots
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作者 吴山东 CHEN +2 位作者 Yimin He Yongyi 《High Technology Letters》 EI CAS 2003年第4期17-20,共4页
With the rapid development of information technology, adopting advanced distributed computing technology to construct robot control system is becoming an effective approach gradually. This paper proposes a distributed... With the rapid development of information technology, adopting advanced distributed computing technology to construct robot control system is becoming an effective approach gradually. This paper proposes a distributed loosely coupled software architecture based on Agent and CORBA to control multiple robots. This model provides the robot user with agent control units at the semantic level and CORBA provides function interfaces to agent at the syntax level, which shows a good adaptability, flexibility and transparence. 展开更多
关键词 agent CORBA ROBOT loosely coupled distributed computing technology
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Multi-soliton solutions, breather-like and bound-state solitons for complex modified Korteweg–de Vries equation in optical fibers
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作者 兰中周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期119-123,共5页
Under investigation in this paper is a complex modified Korteweg–de Vries(KdV) equation, which describes the propagation of short pulses in optical fibers. Bilinear forms and multi-soliton solutions are obtained thro... Under investigation in this paper is a complex modified Korteweg–de Vries(KdV) equation, which describes the propagation of short pulses in optical fibers. Bilinear forms and multi-soliton solutions are obtained through the Hirota method and symbolic computation. Breather-like and bound-state solitons are constructed in which the signs of the imaginary parts of the complex wave numbers and the initial separations of the two parallel solitons are important factors for the interaction patterns. The periodic structures and position-induced phase shift of some solutions are introduced. 展开更多
关键词 complex modified KdV equation multi-soliton solutions breather-like bound-statE
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Loose Body in the Knee Joint: A Case Report
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作者 Hussein Khudhur Joudi Habbal Waleed Mohammed 《Open Journal of Orthopedics》 2024年第10期436-440,共5页
Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;ho... Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;however, their complete eradication is often challenging and may not address underlying diseases, leading to persistent symptoms and the risk of new loose body formation. Aim: This case report aims to present the findings and surgical management of a 52-year-old male with an unusually large osseous loose body in the knee joint and associated pathologies. Case Presentation: The patient, a 52-year-old male, experienced recurrent episodes of severe, sudden, and painful locking of the knee joint, leading to difficulties moving. A plain MRI study was conducted to evaluate the condition of the knee joint, which revealed various degenerative changes and the presence of a loose body. Subsequently, an arthroscopic examination was performed under general anesthesia, uncovering the presence of an abnormally large loose body, as well as other pathologies including chondropathy, meniscal degeneration, and Baker’s cyst. Conclusion: Loose bodies (LBs) in the knee joint pose significant challenges and may lead to debilitating symptoms. Timely diagnosis and appropriate surgical intervention are crucial for symptom relief and the prevention of further joint damage as arthroscopic excision. Comprehensive imaging has a vital role in guiding treatment decisions and optimizing patient outcomes. In this case, the removal of the loose body improved patient outcomes and helped prevent potential joint complications. 展开更多
关键词 loose Bodies Knee Joint ARTHROSCOPY MRI Osseous loose Body Surgical Management Meniscal Degeneration Baker’s Cyst BURSITIS Osteoarthritic Changes Comprehensive Treatment
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Bound-state electrons synergy over photochromic high-crystalline C_(3)N_(5) nanosheets in enhancing charge separation for photocatalytic H_(2) production 被引量:1
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作者 Yu Shen Xin Du +7 位作者 Yuxing Shi Loic Jiresse Nguetsa Kuate Zhouze Chen Cheng Zhu Lei Tan Feng Guo Shijie Li Weilong Shi 《Advanced Powder Materials》 2024年第4期92-102,共11页
Solar-driven water splitting for photocatalytic hydrogen evolution is considered a highly promising and costeffective solution to achieve a stable renewable energy supply.However,the sluggish kinetics of electron-hole... Solar-driven water splitting for photocatalytic hydrogen evolution is considered a highly promising and costeffective solution to achieve a stable renewable energy supply.However,the sluggish kinetics of electron-hole pairs’separation poses challenges in attaining satisfactory hydrogen production efficiency.Herein,we synthesized the exceptional performance of highly crystalline C_(3)N_(5)(HC–C_(3)N_(5))nanosheet as a photocatalyst,demonstrating a remarkable hydrogen evolution rate of 3.01 mmol h^(-1)g^(-1),which surpasses that of bulk C_(3)N_(5)(B–C_(3)N_(5))by a factor of 3.27.Experimental and theoretical analyses reveal that HC-C_(3)N_(5)nanosheets exhibit intriguing macroscopic photoinduced color changes,effectively broadening the absorption spectrum and significantly enhancing the generation of excitons.Besides,the cyano groups in HC-C_(3)N_(5)efficiently captures and converts photoexcited electrons into bound states,thereby prolonging their lifetimes and effectively separating electrons and holes into catalytically active regions.This research provides valuable insights into the establishment of bound electronic states for developing efficient photocatalysts. 展开更多
关键词 bound-state electrons PHOTOCHROMIC C_(3)N_(5) High-crystalline Photocatalytic H2 production
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Uses of Quenchers Methodology in the Management of Loose Smut Disease(Ustilago nuda)of Barley(Hordeum vulgare)through Seed Dressing and SRAP Markers Associated with Resistance in Some Egyptian Barley Genotypes
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作者 Sherin Ph.Mikhail Samah,A.Mariey Ismeal A.Khatab 《Journal of Agricultural Science and Technology(A)》 2024年第4期156-166,共11页
Barley production has been constrained by various factors,of which loose smut(Ustilago nuda)is the main biotic factor.Molecular and agronomical screening analyses were evaluated to study the similarity levels and mark... Barley production has been constrained by various factors,of which loose smut(Ustilago nuda)is the main biotic factor.Molecular and agronomical screening analyses were evaluated to study the similarity levels and marker assisted selection associated with resistance to loose smut among eight barley genotypes using sequence-related amplified polymorphism(SRAP).Agronomical parameters during two consecutive 2021 and 2022 seasons were studied to identify their reaction to loose smut.The results exhibited significant differences among all studied genotypes for all studied characters,and the highest mean values for all studied traits were detected in Giza 136 and Giza 137.Six SRAP selected primer combinations were amplified and gave 56 total fragments,where primer combination me1+em3 gave the highest polymorphism(100%)and the highest polymorphic information content of PIC was 0.96.The dendrogram of SRAP markers had clustered all studied genotypes into two main clusters.Cluster I includes all the resistance genotypes Giza 136,Giza 137,Giza 123,Giza 132,Giza 138 and Line 2.However,cluster II includes only Line 1 and Line 3 as susceptible genotypes.Thus,SRAP marker could be efficiently used to assess genetic variation among barley genotypes and useful for barley germplasm management in terms of biodiversity protection and design of new crosses for loose smut breeding programs,and seed dressings are commonly used to prevent infected seed from developing smutted heads.Some effective seed dressings include Triticonazole,Black seed oil and gamma rays 150,200,250 Gy.The tested fungicide was highly effective in controlling the disease and gave more than 99%disease control with high grain yield while nature product as black seed oil and utilizing radiation gamma ray 250 GY was the most effective.Utilizing radiation and natural ingredients to manage loose barley smut is economical. 展开更多
关键词 Hordeum vulgare loose smut(Ustilago nuda) SRAP UPGMA cluster analysis
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厚松散层下区域注浆改造地层扰动变形特征研究 被引量:1
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作者 张平松 程晋全 +1 位作者 许时昂 吴海波 《煤炭科学技术》 北大核心 2025年第1期246-258,共13页
通过地面高压注浆实施区域治理是厚松散承压含水层下煤炭安全开采的主要防治措施之一,然而高压注浆过程造成上覆地层移动变形,诱发地表局部隆起、矿区建(构)筑物偏斜等问题,是区域注浆改造安全施工备受关注的重点。以安徽某矿120501工... 通过地面高压注浆实施区域治理是厚松散承压含水层下煤炭安全开采的主要防治措施之一,然而高压注浆过程造成上覆地层移动变形,诱发地表局部隆起、矿区建(构)筑物偏斜等问题,是区域注浆改造安全施工备受关注的重点。以安徽某矿120501工作面上覆顶板富水砂岩层注浆改造为工程背景,基于COMSOLMultiphysics有限元方法开展数值模拟,研究高压注浆前后对上覆地层作用过程及其时序演化特征,同时构建了分布式光纤全断面监测系统,获得了上覆地层不同深度地层形变响应特征及对地表扰动影响。结果表明:区域高压注浆过程可划分为“充填—扩散—扰动”3个阶段,充填过程对上覆地层基本无扰动影响,扩散过程对上覆地层影响主要表现为水平扰动,进入扰动阶段对上覆地层影响则表现为垂向位移变化。注浆改造过程对地层扰动影响呈现Logistic曲线增长趋势,其扰动影响主要作用在厚松散层下部,在相对隔水层段以竖向拱起为主,在相对含水层段表现为层内压缩。全断面监测结果表明注浆全过程地层形变特征为非线性分布,砂质黏土层与粉砂层为其主要形变贡献层。全断面监测结果与数值模拟结果具备较好的一致性,成果可为东部厚松散层覆盖矿区煤矿安全开采以及区域注浆诱发次生灾害防治工作开展提供思路和实践参考。 展开更多
关键词 注浆改造 地层变形 分布式光纤 钻孔监测 厚松散层
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长水机场下穿隧道悬臂掘进机施工路径规划及围岩损伤特征分析 被引量:1
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作者 薛亚东 张庆雨 +3 位作者 郭永发 丁文云 杨进京 康殿海 《隧道建设(中英文)》 北大核心 2025年第6期1076-1089,共14页
针对大断面机场下穿隧道施工中爆破法扰动围岩的技术难题,以渝昆高铁长水机场隧道为依托,提出基于悬臂掘进机法的低扰动施工路径规划与围岩损伤演化分析方法。基于FLAC3D软件构建三维数值模型,采用分块多步开挖法模拟悬臂掘进机渐进开... 针对大断面机场下穿隧道施工中爆破法扰动围岩的技术难题,以渝昆高铁长水机场隧道为依托,提出基于悬臂掘进机法的低扰动施工路径规划与围岩损伤演化分析方法。基于FLAC3D软件构建三维数值模型,采用分块多步开挖法模拟悬臂掘进机渐进开挖过程,通过渐进释放围岩荷载,精确表征机械开挖的低扰动特性。结合现场松动圈测试与孔内光学摄像,构建数值模拟与工程实测的交叉验证机制,重点分析悬臂掘进机施工路径及Ⅲ—Ⅴ级围岩条件下位移场、应力场及塑性区的时变特性。研究表明:1)分块多步开挖法可有效模拟悬臂掘进机渐进式开挖特性,数值模拟结果与现场测试数据吻合度高,证实了该方法的科学性及适应性。2)相比于常规掘进路径,分块掘进路径可降低Ⅴ级围岩的拱顶沉降21.7%,有效控制围岩变形。3)围岩损伤特征呈现显著等级相关性,Ⅲ、Ⅳ级围岩损伤集中于隧道轮廓附近,塑性区以拉伸破坏为主;而Ⅴ级围岩损伤范围扩大,剪切破坏占比显著增加。 展开更多
关键词 悬臂掘进机 机场下穿隧道 围岩损伤 松动圈测试 数值模拟 路径规划
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基层政策执行中的“加码”与“减码”行为研究--以A镇“农村人居环境整治”为例 被引量:3
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作者 崔晶 毕馨雨 应宁远 《治理研究》 北大核心 2025年第1期65-80,158,159,共18页
基层政策执行行为是中国基层治理研究中的重要议题。本文基于“组织张力-行为博弈-执行效果”的逻辑链条,通过对S省A镇“农村人居环境整治”政策执行的案例分析,归纳了“乡镇政府内部不同职级人员策略互动”的分析框架。在S省A镇“农村... 基层政策执行行为是中国基层治理研究中的重要议题。本文基于“组织张力-行为博弈-执行效果”的逻辑链条,通过对S省A镇“农村人居环境整治”政策执行的案例分析,归纳了“乡镇政府内部不同职级人员策略互动”的分析框架。在S省A镇“农村人居环境整治”政策执行中,乡镇主要领导通过主动认领政策任务、提高执行标准、缩短执行期限等方式回应上级政府的“加码”要求;而身处基层一线的政策执行人员却表现出分类迎检、缓落实、政策“停摆”等“减码”行为。在科层制主导的基层治理中,乡镇组织的运作方式呈现出“松散关联”的特点。乡镇政府内部的权责失衡、激励偏差、动员失调、情感疏离等多重组织张力,引起了不同职级人员之间的“加码”和“减码”博弈,促进了基层政策执行中的动态平衡。 展开更多
关键词 基层政策执行 基层策略性互动 松散关联 农村人居环境整治
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基于爆破振动与松动圈分析的水封洞库爆破方案比选 被引量:1
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作者 叶海旺 张鹏辉 +6 位作者 蒙云琪 张兆龙 傅家亮 白金鑫 刘磊 余梦豪 Doumbouya Sekou 《爆破》 北大核心 2025年第1期44-55,共12页
合理的爆破施工方式是保证水封洞库稳定性和水封性的关键,在某水封洞库进行爆破地震波检测、声波探测,并结合HHT信号分析方法,通过EMD、EEMD分解方法对比、识别并弱化信号模态混叠效应以提高信号分析准确性,最后利用边际谱、瞬时能量谱... 合理的爆破施工方式是保证水封洞库稳定性和水封性的关键,在某水封洞库进行爆破地震波检测、声波探测,并结合HHT信号分析方法,通过EMD、EEMD分解方法对比、识别并弱化信号模态混叠效应以提高信号分析准确性,最后利用边际谱、瞬时能量谱、三维能量谱、围岩松动圈等评价不同爆破方案对水封洞库开挖爆破的影响。结果表明:EEMD-Hilbert分析方法可以一定程度上改善传统EMD分解带来的模态混叠问题,通过EEMD分解重构后的振速时程曲线更加平滑、可靠性更高;通过信号重构后的边际谱分析,发现双侧壁导坑法频带分布在200~380 Hz范围,单侧壁导坑法的频段范围更窄,集中在110~250 Hz之间,两组方案的低频能量均占比较少;双侧壁导坑法瞬时能量合值高于单侧壁导坑法,两组方案瞬时能量均主要集中在首段掏槽孔上,分别占总瞬时能量的41.67%和23.73%,单侧壁导坑法瞬时能量分布更为平均且较双侧壁导坑法更低;通过声波探测分析:双侧壁导坑法两侧拱腰松动圈范围约1.0~1.2 m,单侧壁导坑法扩挖面、导洞面松动圈范围分别为0.8 m、1.0~1.2 m。通过EEMD-Hilbert与声波探测联合分析可知,单侧壁导坑法相对更适合该洞库爆破施工。 展开更多
关键词 水封洞库 爆破方案 EEMD-HHT 时频能量 松动圈
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支座质量变化下的松动故障转子非线性分析
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作者 刘桂珍 陈光 +2 位作者 胡春玉 袁聪聪 闻邦椿 《中国工程机械学报》 北大核心 2025年第3期444-447,453,共5页
以具有支座松动故障的转子系统为研究对象,建立了6质量12自由度故障转子系统的力学模型,运用数值分析方法提取了该系统随支座质量变化时的非线性动力学特征,研究了系统分岔特性和进入混沌的途径。研究结果表明:当松动故障转子系统的支... 以具有支座松动故障的转子系统为研究对象,建立了6质量12自由度故障转子系统的力学模型,运用数值分析方法提取了该系统随支座质量变化时的非线性动力学特征,研究了系统分岔特性和进入混沌的途径。研究结果表明:当松动故障转子系统的支座质量发生变化时,系统呈现出复杂的非线性动力学特征,所得结论为该类转子故障诊断和系统的安全运行提供理论依据。 展开更多
关键词 支座质量 松动故障 分岔 混沌
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基于改进YOLOv8算法的半刚性基层松散病害识别方法
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作者 张蓓 徐硕 +3 位作者 钟燕辉 蔡鸿健 臧全胜 李晓龙 《郑州大学学报(工学版)》 北大核心 2025年第5期122-129,共8页
针对目前复杂环境下探地雷达对路面松散病害的检测精度差、速度低等问题,提出了一种基于改进YOLOv8算法(YOLOv8-DN)的松散病害识别方法。所提方法针对性设计了DN模块替代C2f模块,该模块结合动态形变卷积模块和多尺度特征融合模块,使用... 针对目前复杂环境下探地雷达对路面松散病害的检测精度差、速度低等问题,提出了一种基于改进YOLOv8算法(YOLOv8-DN)的松散病害识别方法。所提方法针对性设计了DN模块替代C2f模块,该模块结合动态形变卷积模块和多尺度特征融合模块,使用动态形变卷积核的感受野以适应病害特征的形态复杂性,并利用多尺度特征融合路径提升模型对细小和模糊病害区域的捕捉能力。将原结构中的C2f模块替换为DN模块后,改进的YOLOv8-DN算法显著增强了对复杂病害的识别能力,且有效减少了计算开销。实验结果表明:相比原始YOLOv8算法,改进算法的mAP提升了5.29百分点,漏检率降低了5.2百分点,推理速度提高了4.9帧/ms,且检测掩膜区域的完整性和准确性显著提高,证明了该算法的有效性和可行性,也为沥青路面半刚性基层松散病害的快速、精准检测提供了一种新的方法。 展开更多
关键词 探地雷达 改进YOLOv8 松散病害 深度学习 目标检测
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可编程序控制器应用技术活页教材开发 被引量:1
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作者 梁冠英 《河北能源职业技术学院学报》 2025年第1期87-90,共4页
活页式教材是适应职业教育发展的新形式教材,具有灵活性和职业性的特点。基于典型工作任务进行了可编程序控制器应用技术活页式教材的开发。教材从工作岗位和课程定位入手,结合职业教育标准,由易到难精心设计工作任务,多方案解决问题。... 活页式教材是适应职业教育发展的新形式教材,具有灵活性和职业性的特点。基于典型工作任务进行了可编程序控制器应用技术活页式教材的开发。教材从工作岗位和课程定位入手,结合职业教育标准,由易到难精心设计工作任务,多方案解决问题。每个项目都由任务描述、相关知识和工作任务三部分组成,突出理论知识、实践技能和综合素质三个维度。 展开更多
关键词 活页教材 可编程序控制器 任务
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