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Precious Scrolls of Chinese Devout Women Buddhist Followers:A Case Study of Wilt Idema’s Pitfalls of Piety for Married Women
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作者 YAO Wei JIN Qian 《Cultural and Religious Studies》 2023年第4期170-173,共4页
Deeply-rooted in China’s popular culture,precious scrolls(Baojuan)are the golden material to display popular religious belief of the mass.Based on the rare texts sorted and annotated by Shang Lixin,Dutch Sinologist W... Deeply-rooted in China’s popular culture,precious scrolls(Baojuan)are the golden material to display popular religious belief of the mass.Based on the rare texts sorted and annotated by Shang Lixin,Dutch Sinologist Wilt L.Idema continues his journey of translating precious scrolls.Focused on the theme of devoted women Buddhist followers in Ming dynasty,he explores the ethical choices of married women in facing the betrayal of servants or concubines.His translations not only add important reading material to Western readers in the field of Chinese popular literature,but also set standard for the coming translators in rendering Chinese ballads. 展开更多
关键词 Precious Scrolls Women Buddhist followers ethical choice TRANSLATIONS
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Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework
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作者 Jintao Zhang Xingling Shao +1 位作者 Wendong Zhang Zongyu Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期278-287,共10页
This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the fe... This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution. 展开更多
关键词 Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following
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A Novel Prescribed-Performance Path-Following Problem for Non-Holonomic Vehicles
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作者 Zirui Chen Jingchuan Tang Zongyu Zuo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1476-1484,共9页
The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlle... The issue of achieving prescribed-performance path following in robotics is addressed in this paper,where the aim is to ensure that a desired path within a specified region is accu-rately converged to by the controlled vehicle.In this context,a novel form of the prescribed performance guiding vector field is introduced,accompanied by a prescribed-time sliding mode con-trol approach.Furthermore,the interdependence among the pre-scribed parameters is discussed.To validate the effectiveness of the proposed method,numerical simulations are presented to demonstrate the efficacy of the approach. 展开更多
关键词 Guiding vector field non-holonomic vehicle path following prescribed performance sliding mode control
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Finite-Time Sideslip Differentiator-Based LOS Guidance for Robust Path Following of Snake Robots 被引量:3
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作者 Yang Xiu Dongfang Li +5 位作者 Miaomiao Zhang Hongbin Deng Rob Law Yun Huang Edmond Q.Wu Xin Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期239-253,共15页
This paper presents a finite-time sideslip differentiator-based line-of-sight(LOS)guidance method for robust path following of snake robots.Firstly,finite-time stable sideslip differentiator and adaptive LOS guidance ... This paper presents a finite-time sideslip differentiator-based line-of-sight(LOS)guidance method for robust path following of snake robots.Firstly,finite-time stable sideslip differentiator and adaptive LOS guidance method are proposed to counteract sideslip drift caused by cross-track velocity.The proposed differentiator can accurately observe the cross-track error and sideslip angle for snake robots to avoid errors caused by calculating sideslip angle approximately.In our method,the designed piecewise auxiliary function guarantees the finite-time stability of position errors.Secondly,for the case of external disturbances and state constraints,a Barrier Lyapunov functionbased backstepping adaptive path following controller is presented to improve the robot’s robustness.The uniform ultimate boundedness of the closed-loop system is proved by analyzing stability.Additionally,a gait frequency adjustment-based virtual velocity control input is derived to achieve the exponential convergence of the tangential velocity.At last,the availability and superiority of this work are shown through simulation and experiment results. 展开更多
关键词 Line-of-sight(LOS) path following SIDESLIP snake robot
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Constrained Moving Path Following Control for UAV With Robust Control Barrier Function 被引量:1
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作者 Zewei Zheng Jiazhe Li +1 位作者 Zhiyuan Guan Zongyu Zuo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1557-1570,共14页
This paper studies the moving path following(MPF)problem for fixed-wing unmanned aerial vehicle(UAV)under output constraints and wind disturbances.The vehicle is required to converge to a reference path moving with re... This paper studies the moving path following(MPF)problem for fixed-wing unmanned aerial vehicle(UAV)under output constraints and wind disturbances.The vehicle is required to converge to a reference path moving with respect to the inertial frame,while the path following error is not expected to violate the predefined boundaries.Differently from existing moving path following guidance laws,the proposed method removes complex geometric transformation by formulating the moving path following problem into a second-order time-varying control problem.A nominal moving path following guidance law is designed with disturbances and their derivatives estimated by high-order disturbance observers.To guarantee that the path following error will not exceed the prescribed bounds,a robust control barrier function is developed and incorporated into controller design with quadratic program based framework.The proposed method does not require the initial position of the UAV to be within predefined boundaries.And the safety margin concept makes error-constraint be respected even if in a noisy environment.The proposed guidance law is validated through numerical simulations of shipboard landing and hardware-in-theloop(HIL)experiments. 展开更多
关键词 Moving path following(MPF) robust control barrier function safety margin shipboard landing unmanned aerial vehicle(UAV)
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LSTM-DPPO based deep reinforcement learning controller for path following optimization of unmanned surface vehicle 被引量:1
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作者 XIA Jiawei ZHU Xufang +1 位作者 LIU Zhong XIA Qingtao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1343-1358,共16页
To solve the path following control problem for unmanned surface vehicles(USVs),a control method based on deep reinforcement learning(DRL)with long short-term memory(LSTM)networks is proposed.A distributed proximal po... To solve the path following control problem for unmanned surface vehicles(USVs),a control method based on deep reinforcement learning(DRL)with long short-term memory(LSTM)networks is proposed.A distributed proximal policy opti-mization(DPPO)algorithm,which is a modified actor-critic-based type of reinforcement learning algorithm,is adapted to improve the controller performance in repeated trials.The LSTM network structure is introduced to solve the strong temporal cor-relation USV control problem.In addition,a specially designed path dataset,including straight and curved paths,is established to simulate various sailing scenarios so that the reinforcement learning controller can obtain as much handling experience as possible.Extensive numerical simulation results demonstrate that the proposed method has better control performance under missions involving complex maneuvers than trained with limited scenarios and can potentially be applied in practice. 展开更多
关键词 unmanned surface vehicle(USV) deep reinforce-ment learning(DRL) path following path dataset proximal po-licy optimization long short-term memory(LSTM)
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Prospective evaluation of health status, quality of life and clinical outcomes following implantable defibrillator generator exchange
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作者 Faisal M Merchant John Larson +8 位作者 Leon Darghosian Paige Smith Soroosh Kiani Stacy Westerman Anand D.Shah David S.Hirsh Michael S.Lloyd Angel R.Leon Mikhael F.El-Chami 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第9期720-727,共8页
BACKGROUND Little is known about health status and quality of life(QoL)after implantable cardioverter-defibrillator(ICD)generator exchange(GE).METHODS We prospectively followed patients undergoing first-time ICD GE.Se... BACKGROUND Little is known about health status and quality of life(QoL)after implantable cardioverter-defibrillator(ICD)generator exchange(GE).METHODS We prospectively followed patients undergoing first-time ICD GE.Serial assessments of health status were performed by administering the 36-Item Short Form Survey(SF-36).RESULTS Mean age was 67.5±14.3 years,left ventricle ejection fraction(LVEF)was 36.5%±15.0%and over 40%of the cohort had improved LVEF to>35%at the time of GE.SF-36 scores were significantly worse in physical/general health domains compared to domains of emotional/social well-being(P<0.001 for each comparison).Physical health scores were significantly worse among those with medical comorbidities including diabetes,chronic obstructive pulmonary disease and atrial fibrillation.Mean follow-up was 1.6±0.5 years after GE.Overall SF-36 scores remained stable across all domains during follow-up.Survival at 3 years post-GE was estimated at 80%.Five patients died during follow-up and most deaths were adjudicated as non-arrhythmic in origin.Four patients experienced appropriate ICD shocks after GE,three of whom had LVEF which remains impaired LVEF(i.e.,<35%)at the time of GE.CONCLUSION Patients undergoing ICD GE have significantly worse physical health compared to emotional/social well-being,which is associated with the presence of medical comorbidities.In terms of clinical outcomes,the incidence of appropriate shocks after GE among those with improvement in LVEF is very low,and most deaths post-procedure appear to be non-arrhythmic in origin.These data represent an attempt to more fully characterize the spectrum of QoL and clinical outcomes after GE. 展开更多
关键词 ICD quality of life and clinical outcomes following implantable defibrillator generator exchange Prospective evaluation of health status
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Mouse-Sensitive Following Path Suggestion for Drawing Travel Routes in Web Map Systems
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作者 Pablo Martinez Lerin Daisuke Yamamoto Naohisa Takahashi 《Journal of Geographic Information System》 2012年第5期393-402,共10页
This paper proposes a web map system for drawing an arbitrary travel route using a mouse-sensitive following path suggestion. The interaction model of the system allows users to intuitively understand the sequence of ... This paper proposes a web map system for drawing an arbitrary travel route using a mouse-sensitive following path suggestion. The interaction model of the system allows users to intuitively understand the sequence of user actions needed to draw a conceived route and reduces the number of user actions required. Moreover, the system allows users to understand at a glance several drawing alternatives (static suggestion) and also consider a particular drawing alternative (dynamic suggestion) without making any commitment. The proposed architecture of the system reduces the influence caused by communication delay between a map server and a web client by delivering in advance road network data from a map server to a web client. Experimental evaluations on a prototype we developed demonstrated that the proposed system enables users to draw arbitrary routes within noticeably less clicks, in less time, and with less stress than previous systems. 展开更多
关键词 COMPUTER-AIDED RoutE DRAWING followING PATH Web Map System GIS
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Follow-Up Profile and Outcome of Preterms Managed with Kangaroo Mother Care
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作者 Wubishet Lakew Bogale Worku 《Open Journal of Pediatrics》 2014年第2期143-147,共5页
Background: Kangaroo mother care (KMC) is effective in preventing hypothermia, establishing breastfeeding, and reducing nosocomial infection in preterm babies in resource-limited areas. Relatively little is known abou... Background: Kangaroo mother care (KMC) is effective in preventing hypothermia, establishing breastfeeding, and reducing nosocomial infection in preterm babies in resource-limited areas. Relatively little is known about long-term morbidity and mortality outcomes among Ethiopian infants managed with KMC. Aims: To describe the follow up profiles and outcome of infants managed with KMC and discharged alive. Methods: This cross-sectional descriptive study examined outcomes among infants who were 1) managed by KMC at Black Lion Hospital, 2) discharged alive, and 3) available for follow-up. Structured, pretested questionnaires were administered to mothers. Results: Of the 110 infants included in the study, 9.1% died over the study period and 60% of the deaths occurred at home. Mortality was 100% in those babies with mothers aged less than 18 years. Thirty five percent of the deaths occurred in those from rural location. Common medical problems identified in study subjects were respiratory infections (10%), gastroenteritis (7%), rickets (7%), and anemia (6%). About 20% of infants were readmitted to hospital at least once. KMC initiation within one week was not found to be significantly associated with survival, but continued KMC after discharge significantly decreased mortality in our sample. Conclusion: Frequent follow up is very important especially those with teenage mothers and coming from a rural location. Follow up should be frequent in the first 2 months after discharge. Further research is needed to explore the determinants of mortality and morbidity after hospital discharge. 展开更多
关键词 PRETERM Very Low BIRTH Weight KANGAROO Mother Care follow Up PROFILE
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Strengthening Exchanges and Cooperation in the Northeast Asia Region Follows the Trend of the Times——Sidelights of the 10^(th) Northeast Asia Youth Forum
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作者 Wen Desheng Bai Ruijun 《International Understanding》 2013年第4期33-35,共3页
The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seve... The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seventy five college students from 37 universities sent by China International Youth Exchange Center,Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea and Japan Society attended the Forum.Lee Boksil,Vice-Minister of Ministry of 展开更多
关键词 Re Sidelights of the 10 Strengthening Exchanges and Cooperation in the Northeast Asia Region follows the Trend of the Times TH Northeast Asia Youth Forum Asia
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Knowledge,perceptions,and practice towards adverse events following immunization surveillance among vaccination workers in Zhejiang province,China
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作者 Huakun Lv Xuejiao Pan +2 位作者 Ying Wang Hui Liang Hu Yu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第3期102-109,共8页
Objective:To access the level of knowledge,perceptions,and practice towards adverse events following immunization(AEFI)surveillance among vaccination workers in Zhejiang province,China.Methods:This was a cross-section... Objective:To access the level of knowledge,perceptions,and practice towards adverse events following immunization(AEFI)surveillance among vaccination workers in Zhejiang province,China.Methods:This was a cross-sectional survey involving 768 vaccination workers.Data were collected using self-administered questionnaires and analyzed by using SAS 9.3 software.Knowledge,perceptions,and practice on AEFI surveillance were summarized using frequency tables.The mean±SD value was used as the cut-off for defining good(values≥mean)and poor(values<mean)knowledge,perceptions or practice.Binary logistic regression analysis was used to determine sociodemographic variables associated with knowledge,perceptions,and practice towards AEFI.Results:The proportions of good knowledge,perceptions and practice on AEFI surveillance were 78.13%,57.81%and 66.15%,respectively.Having a higher education background,longer years of experience,previous training on AEFI and≥30 years of age were factors associated with good knowledge,perceptions and practice on AEFI surveillance among vaccination workers.Conclusions:Over half of the respondents had good knowledge,perceptions and practice on AEFI surveillance work.Interventions on improving the vaccination workers’knowledge,perceptions and practice on AEFI surveillance should be considered in order to develop a more effective surveillance system. 展开更多
关键词 Adverse events following immunization SURVEILLANCE KNOWLEDGE PERCEPTION PRACTICE
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Investigating the characteristic delay time in the leader–follower behavior in children single-file movement
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作者 薛书琦 Nirajan Shiwakoti +1 位作者 施晓蒙 肖尧 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期567-573,共7页
The single-file movement experiment offered a convenient way to investigate the one-dimensional leader–follower behavior of pedestrians. This study investigated the time delays of children pedestrians in the leader–... The single-file movement experiment offered a convenient way to investigate the one-dimensional leader–follower behavior of pedestrians. This study investigated the time delays of children pedestrians in the leader–follower behavior by introducing a time-dependent delayed speed correlation. A total of 118 German students from the fifth grade(aged11–12 years old) and the 11th grade(aged 17–18 years old) participated the single-file experiment. The characteristic delay time for each pedestrian was identified by optimising the time-dependent delayed speed correlation. The influences of the curvature of the experimental scenario, density, age, and gender on the delay time were statistically examined. The results suggested that to a large extent, the revealed characteristic delay time was a density-dependent variable, and none of the curvatures, the age and gender of the individual, and the age and gender of the leader had a significant influence on it. The findings from this study are variable resources to understand the leader–follower behavior among children pedestrians and to build related simulation models. 展开更多
关键词 speed matching speed correlation CURVATURE following behavior
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Trade credit financing for supply chain coordination under financial challenges:a multi‑leader–follower game approach
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作者 Faranak Emtehani Nasim Nahavandi Farimah Mokhatab Rafiei 《Financial Innovation》 2023年第1期131-169,共39页
This study is designed to solve supply chain inefficiencies caused by some members’financial problems,such as capital shortages and financing restrictions in a stochastic environment.To this end,we have established a... This study is designed to solve supply chain inefficiencies caused by some members’financial problems,such as capital shortages and financing restrictions in a stochastic environment.To this end,we have established a supply chain finance framework by designing two novel coordinating contracts based on trade credit financing for different problem settings.These contracts are modeled in the form of multi-leader Stackelberg games that address horizontal and vertical competition in a supply chain consisting of multiple suppliers and a financially constrained manufacturer.However,previous studies in the trade credit literature have addressed only simple vertical competition,that is,seller-buyer competition.To solve the proposed models,two algorithms were developed by combining population-based metaheuristics,the Nash-domination concept,and the Nikaido-Isoda function.The results demonstrate that the proposed supply chain finance framework can eliminate supply chain inefficiencies and make a large profit for suppliers,as well as the financially constrained manufacturer.Furthermore,the results of the contracts’analysis showed that if the manufacturer is required to settle its payments to suppliers before the end of the period,the trade credit contract cannot coordinate the supply chain because of a lack of incentive for suppliers.However,if the manufacturer is allowed to extend its payments to the end of the period,the proposed trade credit financing contract can coordinate the supply chain.Finally,the sensitivity analysis results indicate that the worse the financial status of the manufacturer,the more bargaining power suppliers have in determining the contract parameters for more profit. 展开更多
关键词 Supply chain coordination Financial constraint Multi-leader–follower Stackelberg game Trade credit financing Population-based metaheuristics
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Following the Inspection Route of Emperor Qianlong
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作者 YI DA 《China Today》 1994年第9期69-70,75-79,共7页
THE AREAS in the southerm part of the villa served as a residence and workplace for the Qing emperors.The scenery takes in all sorts of terrain,including plains,lakes and hills,and is reminiscent of the topography of ... THE AREAS in the southerm part of the villa served as a residence and workplace for the Qing emperors.The scenery takes in all sorts of terrain,including plains,lakes and hills,and is reminiscent of the topography of souther China.From 1713 to 1780,11 monaster-ies were built to the north and east of the villa.Eight have survived the ages,including one still in ruins,and they are known as the Eight Outer Monasteries. 展开更多
关键词 EMPEROR following the Inspection Route of Emperor Qianlong
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We Follow China Out Of Interest
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作者 Victor Sikonina Jacques Fourrier Cui Xiaoqin 《ChinAfrica》 2015年第12期18-19,共2页
Victor Sikonina was born to a Chinese father from Guangdong in south China who immigrated to Madagascar to work in the fishery industry. Life came full circle for the 75-year-old in 2002 when he was appointed Madagas... Victor Sikonina was born to a Chinese father from Guangdong in south China who immigrated to Madagascar to work in the fishery industry. Life came full circle for the 75-year-old in 2002 when he was appointed Madagascar's Ambassador to China. Sikonina, who is also Dean of the African Diplomatic Corps in China, talks to ChinAfrica reporters Jacques Fourrier and Cui Xiaoqin about China-Madagascar and China-Africa cooperation. 展开更多
关键词 We follow China out Of Interest
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利用谱分析法估计GRACE Follow-On地球重力场的空间分辨率 被引量:8
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作者 庞振兴 姬剑锋 +1 位作者 肖云 李迎春 《测绘学报》 EI CSCD 北大核心 2012年第3期333-338,共6页
利用轨道扰动引力谱和大地水准面累计误差谱分析的方法估计未来GRACE(gravity recovery and climateexperiment)Follow-On卫星反演地球重力场的空间分辨率。基于GRACE Follow-On卫星的轨道特性,计算其在高空所受到的径向扰动引力,并根... 利用轨道扰动引力谱和大地水准面累计误差谱分析的方法估计未来GRACE(gravity recovery and climateexperiment)Follow-On卫星反演地球重力场的空间分辨率。基于GRACE Follow-On卫星的轨道特性,计算其在高空所受到的径向扰动引力,并根据谱特性及星载加速度计的测量噪声水平分析该卫星能反演重力场的阶数。利用EGM96重力场模型分别计算200 km和250 km轨道高度处的扰动引力谱。分析其特性表明:在两个轨道高度处分别能反演281阶和242阶的地球重力场模型。给出大地水准面累计误差谱模型,并计算200 km和250 km轨道高度处大地水准面累计误差谱。分析其谱特性表明:在两个轨道高度处分别能反演至286阶和228阶的地球重力场模型。 展开更多
关键词 GRACE follow—On 空间分辨率 扰动引力谱 EGM96重力场模型
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基于Leader-follower与人工势场的多移动机器人编队控制 被引量:5
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作者 张凤 孙哲 刘美菊 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2010年第4期803-807,共5页
目的提出一种基于Leader-follower法和人工势场法相结合的多移动机器人编队控制方法,从而克服传统Leader-follower法中由微分方程确定的控制率无法将队形控制与避障统一的缺点.方法确定关于参数l和φ的人工势场函数,通过控制参数l和φ,... 目的提出一种基于Leader-follower法和人工势场法相结合的多移动机器人编队控制方法,从而克服传统Leader-follower法中由微分方程确定的控制率无法将队形控制与避障统一的缺点.方法确定关于参数l和φ的人工势场函数,通过控制参数l和φ,使多移动机器人保持预定队形;机器人follower通过主动避障方法躲避障碍物,确定一个总的人工势场控制队形和避障.结果算法能使多移动机器人系统成功地进行编队和避障.结论通过仿真试验,机器人系统能够顺利通过狭窄通道,躲避静态障碍物和动态障碍物,并在避障后恢复队形,顺利到达目标,算法简单,从而验证了算法的有效性. 展开更多
关键词 多移动机器人 编队控制 人工势场法 Leader—follower法
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采用Leader-follower和模糊反馈机制的机器鱼队形控制 被引量:4
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作者 单素素 纪志坚 翟海川 《智能系统学报》 CSCD 北大核心 2013年第3期247-253,共7页
在Leader-follower框架下的多机器鱼系统队形控制中,针对Leader和Follower相对独立及落后机器鱼离队等问题,在传统的Leader-follower队形控制算法中引入模糊反馈控制器进行反馈调节,使得领航机器鱼Leader能定时检查Follower的位置,将多... 在Leader-follower框架下的多机器鱼系统队形控制中,针对Leader和Follower相对独立及落后机器鱼离队等问题,在传统的Leader-follower队形控制算法中引入模糊反馈控制器进行反馈调节,使得领航机器鱼Leader能定时检查Follower的位置,将多机器鱼系统的队形控制问题转化为具有反馈调节的Follower跟踪Leader的位置和方向的问题,以增强多机器鱼队形控制的稳定性,更好地协同作业完成任务.仿真试验验证了所提出的方法能较好地实现多机器鱼系统的队形控制. 展开更多
关键词 多机器鱼系统 队形控制 Leader—follower 模糊反馈控制器 反馈调节 协同作业
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FIRST和FOLLOW集合的并行算法设计 被引量:1
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作者 孙玉强 刘三阳 +1 位作者 张英丽 马正华 《计算机工程》 EI CAS CSCD 北大核心 2004年第21期71-73,125,共4页
描述了多处理机环境中 FIRST 和 FOLLOW 集合求解的一种并行处理方法,并讨论了 FIRST 和 FOLLOW 集合的并行算法设计思想和它的实现策略,在构造文法 G 的 LL(1)分析表以及判定文法 G 是否 LL(1)文法时,求解 FIRST 和 FOLLOW 集合是很重... 描述了多处理机环境中 FIRST 和 FOLLOW 集合求解的一种并行处理方法,并讨论了 FIRST 和 FOLLOW 集合的并行算法设计思想和它的实现策略,在构造文法 G 的 LL(1)分析表以及判定文法 G 是否 LL(1)文法时,求解 FIRST 和 FOLLOW 集合是很重要的内容,由于文法中终结符和非终结符个数很多,考虑 FIRST 和 FOLLOW 集合的并行处理方法,对并行编译处理和提高效率有其理论和现实意义。 展开更多
关键词 FIRST集合 follow集合 关系矩阵 并行算法
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Wave Attenuation and Turbulence Driven by Submerged Vegetation Under Current-Wave Flow
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作者 HUANG Yu-ming Ding Lei +3 位作者 WANG Yi-fei CHEN Ben YANG Xiao-yu DOU Xi-ping 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期602-611,共10页
A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave attenuation.Rigid vegetation canopies with aligned and staggered configurations were tested under the co... A set of laboratory experiments are carried out to investigate the effect of following/opposing currents on wave attenuation.Rigid vegetation canopies with aligned and staggered configurations were tested under the condition of various regular wave heights and current velocities,with the constant water depth being 0.60 m to create the desired submerged scenarios.Results show that the vegetation-induced wave dissipation is enhanced with the increasing incident wave height.A larger velocity magnititude leads to a greater wave height attenuation for both following and opposing current conditions.Moreover,there is a strong positive linear correlation between the damping coefficientβand the relative wave height H_(0)/h,especially for pure wave conditions.For the velocity profile,the distributions of U_(min)and U_(max)show different patterns under combined wave and current.The time-averaged turbulent kinetic energy(TKE)vary little under pure wave and U_(c)=±0.05 m/s conditions.With the increase of flow velocity amplitude,the time-averaged TKE shows a particularly pronounced increase trend at the top of the canopy.The vegetation drag coefficients are obtained by a calibration approach.The empirical relations of drag coefficient with Reynolds and Keulegane-Carpenter numbers are proposed to further understand the wave-current-vegetation interaction mechanism. 展开更多
关键词 wave attenuation rigid vegetation following and opposing currents turbulent kinetic energy
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