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1.
航班恢复过程往往会受到不确定因素的干扰,这些不确定因素可能还会进而引发一系列不确定因素的产生,造成更加严重的延误情况。为了提高航班恢复计划的鲁棒性,对不确定因素扰动下的航班恢复问题进行研究。首先,利用中国某机场的地面服务数据,研究了不确定因素对航班恢复过程中地面服务保障时间的影响。然后,建立以最小化延误成本和保证航班公平性为优化目标的航班恢复调度模型;同时考虑进场航班对离场运行的影响;并在模型中加入不确定因素对航班的干扰。最后,运用模拟退火算法对中国某机场的航班数据进行仿真,与先到先服务方法进行对比。结果表明:对于解决机场大面积航班恢复问题具有可行性。  相似文献   

2.
航班恢复过程往往会受到不确定因素的干扰,这些不确定因素可能还会进而引发一系列不确定因素的产生,造成更加严重的延误情况。为了提高航班恢复计划的鲁棒性,对不确定因素扰动下的航班恢复问题进行研究。首先,利用中国某机场的地面服务数据,研究了不确定因素对航班恢复过程中地面服务保障时间的影响。然后,建立以最小化延误成本和保证航班公平性为优化目标的航班恢复调度模型;同时考虑进场航班对离场运行的影响;并在模型中加入不确定因素对航班的干扰。最后,运用模拟退火算法对中国某机场的航班数据进行仿真,与先到先服务方法进行对比。结果表明:对于解决机场大面积航班恢复问题具有可行性。  相似文献   

3.
为了降低航班延误造成的经济损失和旅客滞留,在不增加管制员工作负荷的基础上提高航班运行效率。本文在原有的航班恢复模型基础上,引入跑道容量模型,综合考虑旅客流、航空公司公平性以及航线重要程度的影响,建立了以各单位恢复总成本最小为目标函数的航班恢复模型,该模型适用于跑道数以及构型不同的单一机场,算例中引用国内某机场的真实延误数据,并用遗传算法和粒子群算法求解模型得到优化方案,与遗传算法相比,粒子群更适用于该模型,收敛速度更快。与现有的航班运行相对比,优化后的方案总延误时间缩短了11.85%,总延误成本减少了6.55%。最后用TAAM仿真软件分别运行实际恢复方案和优化恢复方案,报告显示优化方案中终端区产生冲突的可能性更小,管制员工作负荷更低,从而验证了模型和算法的可用性。  相似文献   

4.
为了降低航班延误对旅客满意度的严重不良影响,提高航班延误恢复调度的公平性,将群体情绪模拟引入旅客满意度表征函数,并考虑航空公司公平性约束,构建了机场终端区航班计划恢复模型,运用模拟退火算法对机场航班实例进行仿真求解。与经典FCFS策略对比,所提方法在保证航空公司公平性在可接受水平之内的前提下,使旅客满意度衰减程度下降了41.58%,有效优化了机场运行服务质量。  相似文献   

5.
基于旅客满意度与公平性的机场航班计划恢复   总被引:1,自引:0,他引:1  
为了降低航班延误对旅客满意度的严重不良影响,提高航班延误恢复调度的公平性,将群体情绪模拟引入旅客满意度表征函数,并考虑航空公司公平性约束,构建了机场终端区航班计划恢复模型,运用模拟退火算法对机场航班实例进行仿真求解。与经典FCFS策略对比,所提方法在保证航空公司公平性在可接受水平之内的前提下,使旅客满意度衰减程度下降了41.58%,有效优化了机场运行服务质量。  相似文献   

6.
为了缓解航班大批量延误问题,综合考虑了恶劣天气下对航路扇区容量和目的机场容量约束,建立了以最小化延误总成本的多机场地面等待策略模型,并对航班延误成本进行了系统的研究分析,着重考虑了延误对航空公司的经济影响,指出延误成本与延误时间的指数型增长关系和连程航班的延误累积效应.利用CPLEX优化软件对多机场地面等待模型进行精确求解,根据目的机场接收率的动态变化以及不同航班单位时间延迟费用的不同,对航班的地面延误时间优化.仿真验证了其可行性,算法可求出符合各容量约束条件的满意实时解.  相似文献   

7.
突发事件会导致航班计划无法按原计划执行,给航空公司及旅客带来巨大损失。而航班恢复问题的难点除了相关因素的复杂性,主要的体现在恢复方案的即时性。因此,为了提出快速有效的航班恢复方案,以降低损失,笔者通过时空网络技术对不正常航班的恢复问题进行描述,实现了对航班在空间和时间上的追踪。基于最小费用流模型,建立了以最小总延误时间为目标函数的整数规划模型,模型同时考虑了航班延误,飞机置换及航班取消的调度策略,并提出采用Floyd-Warshall算法对建立的模型进行求解。最后,通过算例对模型及算法进行验证。研究结果表明:针对突发状况,建立的模型及算法可提出合理的航班恢复方案,证明了模型及算法的可行性及有效性。建立的模型具有普适性,对不正常航班恢复问题的研究具有借鉴意义。  相似文献   

8.
随着中国民航业的快速发展,航班延误情况一直较为严重.建立了航班计划优化模型,将软备份运力分配在飞行时间和过站时间中,提高了航班的正常率、起飞的准点率和航班串的鲁棒性;为了进一步提高航班的正常率,追踪航班串中各航班的过站机场和离场时间,用加权马尔科夫链预测处在该时间段的过站机场的延误状态,并针对不同的延误状态作出相应的延误预警,提高了航班运营的可靠性.  相似文献   

9.
航班计划松弛时间是为航班地面过站设置的冗余时间,如果预留过多是对资源的浪费,造成飞机、机组、时间等资源的闲置;但在实际运营中,又是吸收延误的重要手段,如果预留时间过少,将造成延误传播加剧.针对过站松弛时间优化问题,本文构建波及延误树.动态研究以初始航班延误为根节点触发的延误传播过程,建立航班过站松弛时间重分配模型,该模型具有确定性和线性易于求解的优点.通过航空公司的实际运行数据的实验结果表明,提出的模型能够较好地解决松弛时间优化问题,在基本不改变原始的机队和机组调度决策的基础上,不增加计划成本而将波及延误时间降低28%.  相似文献   

10.
机场航班延误优化模型   总被引:29,自引:0,他引:29  
针对空中交通日益严重的航班延误,给出了一种机场航班延误优化模型.模型将机场的到达和出发视为密切相关的两个过程,考虑了具有连续航程的航班(到达和出发均由同一架飞机在当天顺序执行)及其到达和出发过程之间的相互影响.模型还充分考虑了机场容量、需求以及天气等因素的动态特性,在达到和出发过程之间实现流量分配的协同决策.在机场延误不可避免的情况下,该模型可以为管制员提供未来一段时间内的流量分配优化方案,尽量降低延误的后续影响.最后,结合中国某国际机场的实际数据,利用遗传算法对模型进行了验证,取得了很好的效果.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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