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Soil water mixing dynamics and plant hydraulic regulation determine water transport time lags within the soil-plant continuum
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作者 Ziqi Liu Zihe Liu +3 位作者 Guodong Jia Xinxiao Yu Jun Meng Chao Yuan 《Ecological Frontiers》 2026年第1期325-332,共8页
Water transport time lag in the Soil-Plant-Atmosphere Continuum(SPAC)significantly impacts ecosystem hydrology and plant water relations,yet the relative contributions of different segments(soil vs.plant)to the total ... Water transport time lag in the Soil-Plant-Atmosphere Continuum(SPAC)significantly impacts ecosystem hydrology and plant water relations,yet the relative contributions of different segments(soil vs.plant)to the total lag and their response mechanisms under drought remain unclear.This study aimed to quantitatively partition the total SPAC water transport time lag through controlled experiments,identify the dominant component driving the drought response,and compare coexisting tree species with contrasting hydraulic strategies:Platycladus orientalis and Quercus variabilis.We conducted potted plant isotope(δ^(2)H)labeling experiments under normal water and drought stress treatments for both species.Using high-frequency isotope sampling and synchronous sap flow monitoring,we quantified the total water transport time lag from the soil surface to canopy branches(T_(iso),based on initial isotope arrival)and the internal plant transport time lag(T_(sap),based on sap flow path integration).An independent laboratory soil mixing experiment determined the baseline soil mixing time lag(T_(mix)),and the lag associated with soil infiltration and root uptake initiation was estimated(T_(soil)=T_(iso)−T_(sap)).The physical mixing of old and new soil water introduced a baseline time lag(T_(mix))of approximately 8-12 h.Under normal water conditions,the internal plant lag(T_(sap):37-40 h)constituted the major part of the total lag(T_(iso):43-46 h),with the estimated soil process lag(T_(soil))being relatively short(3-9 h).Drought stress significantly prolonged the total time lag.Crucially,this increase was primarily driven by a dramatic increase in the internal plant transport time lag(T_(sap)):T_(sap) increased by 77 h(193%)for P.orientalis and 33 h(89%)for Q.variabilis.In contrast,the estimated soil process lag(T_(soil))showed minimal increase(or even decreased)under drought.Consequently,the increase in T_(sap) almost entirely accounted for the prolongation of T_(iso)(T_(iso) increased by 188%for P.orientalis and 63%for Q.variabilis).Furthermore,the shallow-rooted P.orientalis was more sensitive to drought in terms of internal time lag increase compared to the deep-rooted Q.variabilis.Our direct experimental evidence demonstrates that internal plant physiological and hydraulic processes,rather than soil processes,dominantly regulate the response of total SPAC water transport time lag to drought stress.Tree species with different hydraulic strategies exhibit distinct time lag response mechanisms.These findings challenge traditional perspectives potentially overemphasizing soil limitations and highlight the critical importance of understanding internal plant dynamics for accurately predicting the temporal responses of ecosystem water relations. 展开更多
关键词 Water transport time lag Isotope labeling Soil water mixing Tree water transport
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Effect of Transport Time and Handling on Physiological Responses of Cattle 被引量:1
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作者 Girma Gebresenbet Isabel Wikner +2 位作者 Emmanuel Yaovi Hunnuor Bobobee Gustavo Maria Morris Villarroel 《Journal of Agricultural Science and Technology(A)》 2012年第6期800-814,共15页
The objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to 11 hours, and two sp... The objective of this work was to determine the effect of transport time (up to 11 hours) on animal welfare. 540 animals (cows, bulls and calves), three transport times of 2, 4 to 6, and 10 to 11 hours, and two space allowances (2 m2 and 1.5 m2 per animal for cows and bulls; and 1.2 m2 and 0.8 m2 per animal for calves) were used for the experiment during transport from farms to the abattoir in Uppsala, Sweden. Measurements were made on five animals on each trip. Stress response parameters considered were cortisol, glucose, lactate, creatine kinase and heart rate. Blood samples were taken before and after transport. Heart rate sensors were mounted on the animals at least 30 minutes before loading and measurements were made continuously from farms to the abattoirs until stunning. The results of heart rate measurement indicated that loading, un-loading and forced movement in the stunning box were the most stressful events. However, the results of statistical analysis confirmed that transport time doesn't have significant effect (P 〈 0.05) on heart rate. Concentration level of cortisol increased by 10 folds during short transport. However, cortisol concentration decreased with an increase of transport times (P 〈 0.01). Glucose concentrations increased with transport time in all animal categories (P ≤ 0.01). Transport time has significant effect on concentration levels of glucose (P ≤ 0.01), creatine kinase (P 〈 0.001) and lactate (P 〈 0.01) particularly after 6 hours journey time. 展开更多
关键词 transport time CATTLE WELFARE physiological parameters
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Impact of prehospital medical evacuation (MEDEVAC) transport time on combat mortality in patients with noncompressible torso injury and traumatic amputations: a retrospective study
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作者 Joseph K.Maddry Crystal A.Perez +3 位作者 Alejandra G.Mora Jill D.Lear Shelia C.Savell Vikhyat S.Bebarta 《Military Medical Research》 SCIE CAS CSCD 2019年第1期23-30,共8页
Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality... Background: In combat operations, patients with traumatic injuries require expeditious evacuation to improve survival. Studies have shown that long transport times are associated with increased morbidity and mortality. Limited data exist on the influence of transport time on patient outcomes with specific injury types. The objective of this study was to determine the impact of the duration of time from the initial request for medical evacuation to arrival at a medical treatment facility on morbidity and mortality in casualties with traumatic extremity amputation and noncompressible torso injury(NCTI).Methods: We completed a retrospective review of MEDEVAC patient care records for United States military personnel who sustained traumatic amputations and NCTI during Operation Enduring Freedom between January 2011 and March 2014. We grouped patients as traumatic amputation and NCTI(AMP+NCTI), traumatic amputation only(AMP),and neither AMP nor NCTI(Non-AMP/NCTI). Analysis was performed using chi-squared tests, Fisher's exact tests,Cochran-Armitage Trend tests, Shapiro-Wilks tests, Wilcoxon and Kruskal-Wallis techniques and Cox proportional hazards regression modeling.Results: We reviewed 1267 records, of which 669 had an injury severity score(ISS) of 10 or greater and were included in the analysis. In the study population, 15.5% sustained only amputation injuries(n=104, AMP only), 10.8% sustained amputation and NCTI(n=72, AMP+NCTI), and 73.7% did not sustain either an amputation or an NCTI(n=493,Non-AMP/NCTI). AMP+NCTI had the highest mortality(16.7%) with transport time greater than 60 min. While the AMP+NCTI group had decreasing survival with longer transport times, AMP and Non-AMP/NCTI did not exhibit the same trend.Conclusions: A decreased transport time from the point of injury to a medical treatment facility was associated with decreased mortality in patients who suffered a combination of amputation injury and NCTI. No significant association between transport time and outcomes was found in patients who did not sustain NCTI. Priority for rapid evacuation of combat casualties should be given to those with NCTI. 展开更多
关键词 transport time Non-compressible TORSO INJURY Traumatic amputation COMBAT
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An experimental analysis on the turnover time of railway freight transportation based on the impact strength of factors 被引量:4
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作者 张光远 DING Xiao-dong +1 位作者 鲁工圆 于洋 《Journal of Chongqing University》 CAS 2017年第3期113-123,共11页
Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The resul... Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The results show that wagon transfer time is the most critical factor among the three subjective factors of wagons turnover time. The FISM based analysis of wagon transfer time show that the wagon turnover time is significantly correlated with transit time with resorting. Among the seven factors of detention time of transit time with resorting, the time of waiting to departing, converging, and waiting to break-up are key factors, while the time of make-up, break-up, arrival and departure are general factors. We carried out one empirical research based on the data of Baoji East Railway Station in 2015. The results of empirical research and FISM are consistent completely. 展开更多
关键词 railway transportation wagon turnover time impact strength wagon transfer time correlation coefficient method
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New Procedure of Finding an Initial Basic Feasible Solution of the Time Minimizing Transportation Problems
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作者 Mollah Mesbahuddin Ahmed Md. Amirul Islam +2 位作者 Momotaz Katun Sabiha Yesmin Md. Sharif Uddin 《Open Journal of Applied Sciences》 2015年第10期634-640,共7页
Minimization of transportation time is a great concern of the transportation problems like the cost minimizing transportation problems. In this writing, a transportation algorithm is developed and applied to obtain an... Minimization of transportation time is a great concern of the transportation problems like the cost minimizing transportation problems. In this writing, a transportation algorithm is developed and applied to obtain an Initial Basic Feasible Solution (IBFS) of transportation problems in minimizing transportation time. The developed method has also been illustrated numerically to test the efficiency of the method where it is observed that the proposed method yields a better result. 展开更多
关键词 transportATION PROBLEM INITIAL Basic Feasible SOLUTION Minimizing transportATION time
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Real-Time Observation of Protein Transport across Membranes by Femtosecond Sum Frequency Generation Vibrational Spectroscopy
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作者 Junjun Tan Chuanzhao Li +1 位作者 Jiahui Zhang Shuji Yea 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第4期523-528,615,共7页
Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dyna... Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dynamic structures of proteins at the interfaces with suffi- cient structural and temporal resolutions. Here, we demonstrate that a ferntosecond sum frequency generation vibrational spectroscopy (SFG-VS) system developed by our group provides a powerful tool for monitoring the real-tirne peptide transport across the membranes with time resolution of less than one second. By probing the real-time SFG signals in the arnide I and arnide A bands as WALP23 interacts with DMPG lipid bilayer, it is found that WALP23 is initially absorbed at the gel-phase DMPG bilayer with a random coil structure. The absorption of WALP23 on the surface leads to the surface charge reversal and thus changes the orientation of rnembrane-bound water. As the DMPG bilayer changes from gel phase into fluid phase, WALP23 inserts into the fluid-phase bilayer with its N-terminal end moving across the membrane, which causes the membrane dehydration and the transition of WALP23 conformation from random coil to mixed helix/loop structure and then to pure α-helical structure. The established system is ready to be employed in characterizing other interracial fast processes, which will be certainly helpful for providing a clear physical picture of the interracial phenomena. 展开更多
关键词 Ferntosecond sum frequency generation Peptide transport across membrane Real time Kinetic conformation
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Jump Drive, Replicators, Transporters, and Time Travel 被引量:1
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作者 Yosef Joseph Segman 《Advances in Aerospace Science and Technology》 2021年第3期123-133,共11页
Jumping from place to place, replicating food, biological or mechanical parts or beaming up somebody, may not be fiction, rather an issue of practical implementation as shall be observed in this paper. Devices like tr... Jumping from place to place, replicating food, biological or mechanical parts or beaming up somebody, may not be fiction, rather an issue of practical implementation as shall be observed in this paper. Devices like transporter, food replicators or warp drive intrigue our imagination. This paper is intended to show that Jump drive is an issue of coordinate transformation. Changing location from planet X to planet Y does not necessarily require travelling a distance D connecting between the two planets. The theoretical knowledge of changing the location from coordinate X to coordinate Y exists;we do that in signal processing, but, we have not yet developed such a machine. The present paper shows the feasibility of jump drive;however, much work needs to be done on the implementation. 展开更多
关键词 Fourier Transform Spatial Shift time Shift Coordinates Transformation time Travel Discontinuous Travel transporters Replicators CAUSALITY Noncausality
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钢桥板单元分布式柔性作业车间成组调度
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作者 朱斌 马骁 +1 位作者 李稷丰 雷景媛 《郑州大学学报(工学版)》 北大核心 2026年第1期41-48,共8页
针对钢桥板单元生产速度过慢会直接制约桥梁工程建设周期的问题,在考虑钢桥板单元的加工工艺路线和生产特点的同时,以最小化最大完工时间为目标,建立了考虑顺序相关作业切换时间和运输时间,面向钢桥板单元加工的分布式柔性作业车间成组... 针对钢桥板单元生产速度过慢会直接制约桥梁工程建设周期的问题,在考虑钢桥板单元的加工工艺路线和生产特点的同时,以最小化最大完工时间为目标,建立了考虑顺序相关作业切换时间和运输时间,面向钢桥板单元加工的分布式柔性作业车间成组调度(DFJGSPST)模型,并提出了基于三层编码的记忆混合遗传禁忌搜索算法(MGATS)。为验证数学模型和智能算法的可行性,以某钢桥板单元生产为例,建立了包括4种板单元组和15台机器的DFJGSPST模型,通过相应的测试算例进行实验验证,并与其他智能算法进行比较分析。实验结果表明:所提的MGATS的相对百分比差异(RPD)的均值为2.74%,低于遗传算法(GA)的3.99%和混合遗传禁忌搜索算法(GATS)的3.13%。MGATS的成功率(SR)为0.15,高于GATS和GA,验证了MGATS在求解DFJGSPST模型中的稳定性和鲁棒性。 展开更多
关键词 钢桥板单元 柔性作业车间 成组调度 顺序相关 运输时间 混合遗传禁忌搜索算法
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A time-space network based international transportation scheduling problem incorporating CO_2 emission levels
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作者 Takashi IROHARA 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第12期927-932,共6页
Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 ... Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 emissions.Therefore,the CO2 emission reduction of the transport sector is of great importance.In order to reduce emissions effectively,it is necessary to change the distribution and transportation processes.The purpose of this study is to minimize both the transportation costs and CO2 emissions during transportation.Our model considers a transportation scheduling problem in which loads are transported from an overseas production base to three domestic demand centers.The need for time-space networks arises naturally to improve the model.It is possible to know the distance carriers are moving,and also consider the timetables of carriers during transportation.Carrier choice,less-than carrier load,and domestic transportation among demand centers are considered as the three target areas to reduce CO2 emissions during the distribution process.The research model was formulated as a mixed integer programming (MIP) problem.It achieves cost reduction,and will contribute to improvement of the natural environment. 展开更多
关键词 time-space network timeTABLE transportation scheduling problem Mixed integer programming (MIP) problem Less-than carrier load
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A Preliminary Study of Just-in-Time Methods for a Seamless Public Transportation Information Framework
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作者 Spring C. Hsu 《Intelligent Information Management》 2012年第1期1-5,共5页
A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL)... A seamless multimodal transit system has been a goal for transportation planners and users. Owing to the developments of advanced public transportation and telecom technologies such as automatic vehicle location (AVL) and real-time passenger information system, key just-in-time (JIT) concepts can now be realized in process design and coordinated scheduling to shape a seamless multimodal transit system. JIT refers to a production system that times both movements of goods during production and delivery from suppliers together. It meets the same logic for seamless multimodal services. Therefore, this study innovatively analyzes possible public transportation technologies for JIT uses;moreover, to layout the possible application frame-work of a transportation technology based JIT multimodal transit system for main station area in Taipei city. With this innovative framework, multimodal transit services can deliver to the right place at right time. 展开更多
关键词 JUST-IN-time (JIT) KANBAN Management Mixed-Model Production PUBLIC transportATION SEAMLESS Services
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基于TIMES模型的客运交通低碳化研究——以北京市为例 被引量:5
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作者 赵立祥 王宇奇 《北京理工大学学报(社会科学版)》 CSSCI 2015年第5期50-55,共6页
为研究低碳城市环境下居民的客运交通出行,以综合能源优化模型——TIMES(The Integrated MARKALEFOM System)模型为分析工具,构建客运交通模型。该模型考虑了出行成本、出行选择行为、碳减排目标等的影响,同时以北京市为例,设计基准情景... 为研究低碳城市环境下居民的客运交通出行,以综合能源优化模型——TIMES(The Integrated MARKALEFOM System)模型为分析工具,构建客运交通模型。该模型考虑了出行成本、出行选择行为、碳减排目标等的影响,同时以北京市为例,设计基准情景和3个参考情景并对不同情景进行分析和讨论。结果显示:当减少出行时间投资成本非常高时,居民很大程度上通过小汽车来满足居民出行需求。在CO2排放限制情景下,小汽车出行需求不断下降,道路公交和轨道交通出行需求稳步上升。基于上述结果得出北京市客运交通低碳化发展的对策和建议:即调控出行需求结构;优化交通出行结构;调整交通能源结构;完善交通治理结构。 展开更多
关键词 客运交通 timeS模型 出行成本 出行选择行为 减排目标
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A Review of Comminution Age Method and Its Potential Application in the East China Sea to Constrain the Time Scale of Sediment Source-to-Sink Process 被引量:5
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作者 LI Chao YANG Shouye +2 位作者 LIAN Ergang BI Lei ZHANG Zhaofeng 《Journal of Ocean University of China》 SCIE CAS 2015年第3期399-406,共8页
The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detr... The East China Sea(ECS) is a river-dominated epicontinental sea, linking the Asian continent to the northwestern Pacific via the large rivers originating from Tibetan Plateau. The relevant huge influx of riverine detritus has developed unique sedimentary systems in the ECS during the Quaternary, offering ideal terrestrial archives for reconstructing Quaternary paleoenvironmental changes and studying land-sea interactions. Overall, two characteristic river systems dominate the sedimentary systems and sediment source to sink transport patterns in the ECS, represented by the Changjiang(Yangtze River) and Huanghe(Yellow River) for the large river system and Taiwan rivers for the small river system. Given this, the sediments derived from both river systems bear distinct features in terms of parent rock lithology, provenance weathering and sediment transport. Previous studies mostly focus on either the ‘source' discrimination or the ‘sink' records of the sedimentary system in the ECS, while the source to sink process linking the land and sea, in particular its time scale, has been poorly understood. Here we introduce a newly-developed dating technique, the ‘comminution age' method, which offers a quantitative constraint on the time scale of sediment transfer from its ultimate source to the final depositional sink. This novel method is of great significance for improving our understanding on the earth surface processes including tectonic-climate driven weathering, and sediment recycling in relation to landscape evolution and marine environmental changes. The application of comminution age method in the ECS will provide important constraints on sediment source-to-sink process and more evidences for the construction of late Quaternary paleoenvironmental changes under these unique sedimentary systems. 展开更多
关键词 sediment transport time 234U/238U East China Sea source to sink
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基于约束卡尔曼滤波的信控干线动态OD估计
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作者 郭瑞军 盛诣皓 +1 位作者 姜凯宁 郝梓彤 《交通运输系统工程与信息》 北大核心 2026年第1期55-64,共10页
针对城市干线多路径交通需求时变,传统的OD估计方法难以满足信号协调控制对精度与实时性的要求,本文提出一种基于等式约束卡尔曼滤波的干线动态OD估计方法。模型首先建立干线中转向流量与OD之间的时空映射关系,分析信控交叉口上游信号... 针对城市干线多路径交通需求时变,传统的OD估计方法难以满足信号协调控制对精度与实时性的要求,本文提出一种基于等式约束卡尔曼滤波的干线动态OD估计方法。模型首先建立干线中转向流量与OD之间的时空映射关系,分析信控交叉口上游信号配时对下游车流量到达的关系,增加额外等式关系引入观测方程以提高模型准确性。为确保状态估计满足流量守恒等物理约束,采用带等式约束的卡尔曼滤波方法,并基于最小均方误差原则推导状态修正机制并求解模型。以大连市山东路干线交通为应用案例,结果表明:关键路径OD的平均绝对百分比误差(MAPE)分别为12.3%和17.5%。与传统转向流量模型相比,所提方法在精度上具有一定提升,能更好地捕捉OD流量的时变特征,可以为干线多路径信号协调控制提供可靠的实时输入。 展开更多
关键词 城市交通 动态OD估计 约束卡尔曼滤波 信号配时条件 转向流量
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民用运输机场航班截载时间影响因素研究
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作者 李明捷 冯思蓉 殷天策 《重庆交通大学学报(自然科学版)》 北大核心 2026年第2期76-84,共9页
航班截载时间的合理设置对提升机场服务效率、提高旅客航空出行体验感等方面发挥着重要作用,探究其影响机制,可为机场按需制定及优化航班截载时间提供一定的理论参考依据。首先在文献研究和调研结果确定15个主要影响因素的基础上建立航... 航班截载时间的合理设置对提升机场服务效率、提高旅客航空出行体验感等方面发挥着重要作用,探究其影响机制,可为机场按需制定及优化航班截载时间提供一定的理论参考依据。首先在文献研究和调研结果确定15个主要影响因素的基础上建立航班截载时间影响因素体系;其次,将Grey-DEMATEL-TAISM相结合,计算各影响因素原因度、中心度排序,进而确定2个根源性关键影响因素、4个敏感性关键影响因素和1组互为因果关系的关键影响因素。研究结果表明:旅客流线设计、离港资源配置、航班地面保障服务、地面保障设备配置、协同运行水平是影响航班截载时间的重要因素,其中旅客流线设计是强驱动型因素,运行管理中需重点关注;位于拓扑图底层的旅客吞吐量、航站楼构型是根源影响因素,可通过前期规划阶段合理预测吞吐量,采用一场多楼替代大型单体候机楼等方式改进;因果回路中的因素所属分类涵盖旅客流、行李流和航班流,需充分重视3个系统间的牵制关系,通过协同管理来提升机场的运行效率。 展开更多
关键词 交通运输工程 机场运行管理 航班截载时间 决策与评价实验室法 综合对抗解释结构模型 灰数理论
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具时滞的Rotenberg方程主算子的谱分析
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作者 童雅阁 吴开谡 《北京化工大学学报(自然科学版)》 北大核心 2026年第1期146-151,共6页
1983年Rotenberg为了描述种群细胞增生首次提出Rotenberg模型,引起了广泛的关注,然而以往在对Rotenberg模型的研究过程中并没有考虑到细胞分裂的时滞性。为了更准确地描述细胞增生,在前人研究的基础上,考虑细胞分裂的时滞性对原有的Rote... 1983年Rotenberg为了描述种群细胞增生首次提出Rotenberg模型,引起了广泛的关注,然而以往在对Rotenberg模型的研究过程中并没有考虑到细胞分裂的时滞性。为了更准确地描述细胞增生,在前人研究的基础上,考虑细胞分裂的时滞性对原有的Rotenberg模型作出一定的修改,证明迁移算子A_(H)能够生成C0半群;并且对相应的迁移算子的谱进行分析,得到该迁移算子的谱在区域Γ=σ(A_(H))∩{λ∈C|Reλ>γ}(其中γ>λ_(0))中仅由有限个具有有限代数重数的离散本征值组成等结果。 展开更多
关键词 Rotenberg模型 迁移算子 C0半群 时滞性 谱分析
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基于合适空隙数量的智能网联车队高速公路出匝换道时机决策
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作者 陈华伟 邵毅明 +2 位作者 徐进 敖谷昌 张惠玲 《重庆交通大学学报(自然科学版)》 北大核心 2026年第3期81-89,共9页
为迎合高速公路高度自动驾驶的发展需要,以高速公路出匝换道为研究场景,针对车队在驶入出口匝道前何时换道的问题,提出一种基于合适空隙数量的智能网联车队高速公路出匝换道时机决策模型。首先,建立空隙数量与长度的概率分布,在此基础上... 为迎合高速公路高度自动驾驶的发展需要,以高速公路出匝换道为研究场景,针对车队在驶入出口匝道前何时换道的问题,提出一种基于合适空隙数量的智能网联车队高速公路出匝换道时机决策模型。首先,建立空隙数量与长度的概率分布,在此基础上,估计合适空隙数量,通过不断拓展搜索空间的方式积累其中包含的合适空隙数量,根据合适空隙数量的水平估计最短搜索距离;其次,建立换道距离的概率分布,以一个合适分位数对应的换道距离定义合理换道距离;然后,在最短搜索距离与合理换道距离基础上,建立最短预留距离的最优化模型,以此实现车队换道时机决策;最后,通过设置对比实验,验证模型的可操作性与可行性。仿真分析结果显示:相较于车队进入道路就开始搜索空隙并换道的方式,当车队车辆数为2时,2个模型的车队换道成功率持平;当车队车辆数为4时,2个模型的车队换道成功率均升高了82%;相较于车队邻近允许换道终止位置才开始搜索空隙并换道的方式,当车队车辆数为2时,2个模型的车队换道位置至允许换道终止位置的距离分别缩短了61%与43%;当车队车辆数为4时,2个模型的车队换道位置至允许换道终止位置的距离分别缩短了19%与增加了37%。综上,相较于无车队换道时机决策下的车队换道,车队换道时机决策下的车队换道能有效兼顾换道成功率与换道位置至允许换道终止位置的距离。 展开更多
关键词 交通运输工程 换道时机决策 数学建模 智能网联车队 出匝换道 合适空隙
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“脾主时”理论指导下探讨生物节律紊乱与肥胖症的关系
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作者 李笑妍 王钰 +1 位作者 路童 战丽彬 《世界科学技术-中医药现代化》 北大核心 2026年第2期374-380,共7页
肥胖症患病率持续攀升,已成为威胁人类健康的重大公共问题。生物节律的紊乱会增加罹患慢性代谢性疾病尤其是肥胖症的风险。“脾主时”的时间观是基于脾属土居中央的空间观而形成,并发展出时空逻辑统一的脏时理论。“脾主时”揭示了脾在... 肥胖症患病率持续攀升,已成为威胁人类健康的重大公共问题。生物节律的紊乱会增加罹患慢性代谢性疾病尤其是肥胖症的风险。“脾主时”的时间观是基于脾属土居中央的空间观而形成,并发展出时空逻辑统一的脏时理论。“脾主时”揭示了脾在人体生命中的核心地位,昼夜节律可能是“脾主时”的重要体现。中医脾在物质代谢过程中扮演着核心角色,是维持后天生命活动的关键。当脾功能失常,无法有效地转化食物为精血输送营养、滋养全身时,导致膏脂痰湿的积聚,最终在体内蓄积,形成肥胖症。因此,本文认为肥胖症的发生发展与生物节律的变化密切相关,在中医“脾主时”理论指导下,本文分别从饮食行为、压力应激、肠道菌群、肌肉运动、免疫功能五个方面对生物节律紊乱与肥胖症的关系进行系统阐释,旨在为从“中医脾-生物节律”角度防治肥胖症提供参考,丰富和深化中医“脾主时”理论。 展开更多
关键词 脾主时 脾主运化 生物节律 脂代谢 肥胖症 理论探讨
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随机交通网络约束最可靠路径乘子交替方向法
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作者 潘义勇 曹天宇 刘宇 《吉林大学学报(工学版)》 北大核心 2026年第2期455-463,共9页
为分析行程时间相关性和资源约束对交通网络最可靠路径选择的影响,建立考虑行程时间相关性的随机交通网络约束最可靠路径模型,提出了改进乘子交替方向法的求解方法。通过Cholesky分解和二次项放缩,将目标函数转化为可分离结构的矩阵形式... 为分析行程时间相关性和资源约束对交通网络最可靠路径选择的影响,建立考虑行程时间相关性的随机交通网络约束最可靠路径模型,提出了改进乘子交替方向法的求解方法。通过Cholesky分解和二次项放缩,将目标函数转化为可分离结构的矩阵形式,采用块坐标下降法将增广拉格朗日松弛问题分解为一系列子问题,上下界迭代获得近似最优解。针对Sioux Falls网络和Chicago sketch网络进行数值模拟试验并对比分析改进交替方向法和拉格朗日松弛算法的性能。结果表明:有无路段行程时间相关性的约束最可靠路径问题是有区别的;行程时间相关性和资源约束对最可靠路径的选择有显著影响;改进乘子交替方向法的计算效率和收敛性优于拉格朗日松弛算法。 展开更多
关键词 交通运输系统工程 随机网络 约束最可靠路径 行程时间相关性 乘子交替方向法
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优化实时交通流检测:一种将YOLO与图像预处理结合的研究
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作者 孙嘉豪 邹瑞滨 +3 位作者 李和福 高扬 张葳琳 刘沅鑫 《聊城大学学报(自然科学版)》 2026年第2期238-248,共11页
为提高城市交通管理效率,应用智能交通系统是当前较为高效可行的办法,车流量实时监测技术可为整个系统提供有效的实时数据,研究聚焦于提升车流量实时监测终端设备性能的关键需求,提出一种基于YOLO目标检测算法的方法,结合图像预处理技... 为提高城市交通管理效率,应用智能交通系统是当前较为高效可行的办法,车流量实时监测技术可为整个系统提供有效的实时数据,研究聚焦于提升车流量实时监测终端设备性能的关键需求,提出一种基于YOLO目标检测算法的方法,结合图像预处理技术提升系统准确度并减少了终端资源消耗。研究基于CO-CO公开数据集整理和处理部分素材图,构建符合本次测试的自训练数据集,分别训练YOLOv5s与YOLOv8s模型,在动态视频和实时视频流等多种场景下进行全面测试,同时引入背景差分、CLAHE图像增强和中值滤波等图像预处理技术,有效验证了模型在复杂环境下对目标识别能力的提升,同时降低了设备资源占用。实验结果说明,图像预处理技术在不同测试方式和环境下提高约1.2%~1.8%的检测精度,相应的资源占用情况也有所降低,研究设计并分析了从模型训练、图像处理及性能评估等主要环节,凭借一系列视频测试和现实模拟测试得出相应数据,有一定应用价值。 展开更多
关键词 智能交通 (YOLO) 车流量实时监测 模型训练 图像预处理
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基于NSACO-Ⅱ算法的稳定供应能源指挥控制大模型研究
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作者 陈宇昕 王帅 熊彪 《自动化与仪器仪表》 2026年第1期12-16,共5页
由于现有油料能源运输指挥控制方法存在效率低下的问题,因此,为提高油料能源运输指挥控制的效率和安全性,研究提出了基于非支配排序蚁群优化Ⅱ算法的运输指挥控制模型。实验以新疆克拉玛依市为案例,对模型进行测试。实验结果显示,非支... 由于现有油料能源运输指挥控制方法存在效率低下的问题,因此,为提高油料能源运输指挥控制的效率和安全性,研究提出了基于非支配排序蚁群优化Ⅱ算法的运输指挥控制模型。实验以新疆克拉玛依市为案例,对模型进行测试。实验结果显示,非支配排序蚁群优化Ⅱ算法,能同时降低运输成本和运输时间。在克拉玛依-广州运输方案规划中,其运输成本和时间分别为249.5万元、41.3 h。在克拉玛依-福州的运输方案规划中,其运输成本和时间313.7万元、50.8 h。上述结果表明,非支配排序蚁群优化Ⅱ算法能更为合理地规划油料能源运输方案,同时降低运输成本和时间,提高能源供应链的稳定性。研究为油料能源运输指挥控制提供了一种新的优化方法,具有重要的理论和实际应用价值。 展开更多
关键词 能源运输指挥控制 产能约束 时间约束 NSACO-Ⅱ
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