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1.
为充分利用电子、通信、计算机、GPS等现代高新技术对智能公共汽车运营调度提供的支持,本文利用Visual FoxPro开发公交运营调度系统计算机管理平台,该平台实现了公交运行实时数据的统计和快速处理,并考虑未来需求量和服务质量等因素,自动编制行车时刻表,从而提高了运营调度管理的智能化水平,提高了公交运营效益和乘客满意度,能够为现行公交行业实现先进的营运调度提供技术支持.  相似文献   

2.
运行瓶颈诊断对公交发车时刻表调整和车辆调度优化具有重要意义。从公交乘客和公交运营企业的不同关切点出发,结合公交GPS和IC卡等实时运营数据,提出一种公交运行瓶颈诊断方法。在公交企业运营效益、公交乘客出行效率等因素分析的基础上,分别从站点层面提出公交车头时距、车辆延误度等运行评价方法,在线路层面构建公交行程时间与运输效益评价方法,以及基于站点、线路评价结果的线网层面综合分析方法。最后,利用案例获取的公交车位置、行驶速度、公交乘客数量等实时数据,以及公交站点、线路、线网和调度方案等静态数据,对所提方法进行检验。结果表明,公交运行瓶颈诊断结果与公交实际运行状况具有较高符合度,能够实时、有效反应公交运行状态,具有较好的工程实用价值。  相似文献   

3.
为改善城市低需求时空下交通供需不平衡问题,提出一种面向交通低出行需求场景的实时预定公交动态调度系统。当低需求时空下的出行者发出预定请求后,调度系统根据时空阈值筛选出满足条件的公交集;采用启发式最短路径算法和Python工具实现动态公交的路径规划;并利用响应判断函数计算出效益为正的公交子集,估算出公交预期到站时间并按到站时间由短至长排列出供乘客选择的公交方案,调度系统根据乘客选定方案指派公交并实时反馈公交信息给乘客。以重庆市396路公交线路为案例,验证了提出系统的可实施性;在三种乘客比例情景下测算乘客候车时间并与传统模式进行对比,结果表明,公交发车间隔增加20%时,乘客候车时间仍将减少53%以上。实时预定公交动态调度系统可有效提高低需求时空下乘客出行效率和公交运营效率。  相似文献   

4.
为使公交到站时间符合计划时刻表,该文统筹考虑实时路网状态及客流需求,建立电动公交调度双阶段协同优化模型。路网轻微拥堵时,构建以提高公交服务水平与降低运营成本为目标,以电动公交续航里程与充电时间为约束的优化模型,运用非支配排序遗传算法(NSGA-Ⅱ)求解,得出优化后发车间隔;路网严重拥堵时,构建全程车与区间车组合调度模型,运用模拟退火算法求解,得出组合调度发车时刻表。基于北京市361路运营数据对模型进行验证。结果表明,在满足客流需求且不增加运营成本的前提下,该文模型能够显著提升乘客满意度,公交准点率提高82.38%,乘客平均候车时间减少182.2 s。  相似文献   

5.
利用先进的技术和设备实现公交的优化调度,充分满足人们的出行需要,是智能公交系统发展的目标.然而近年来中国智能公交发展在一定程度上出现过于追求先进性、忽略实用性、运营效果不理想、动态调度尚待充分开发等问题.结合中国智能公交系统现状,通过对智能公交调度系统和调度特点深入分析,在GPS定位、通信、计算机等技术的支持下,将动态交通状态信息与车辆定位信息有效融合,将智能化算法引入到公交运营调度中,建立了基于实时动态数据,兼顾乘客满意度和企业效益的动态调度优化模型.并且阐述了模型数据的自动采集方法、模型Matlab程式化的解法.结果表明,该模型可以显著提高公交车辆满载率、缩短乘客等车时间和减少车辆总班次,优化调度效果明显.  相似文献   

6.
公交运营调度是公交行业运营管理的重要步骤,规划合理的行车时间对提高公交的承载率至关重要。本文以企业与乘客两个方面建立公交车发车频率的多目标优化模型,采用遗传算法,用matlab编程求解,并将人工制定方案与本文制定方案在高峰期、平峰期两个时间段的平均发车间隔进行比较。结果表明本文的计算方法性能更优,在满足乘客需求的同时也为公交运营公司提供决策支持,具有较好的应用价值。  相似文献   

7.
针对居住在城市外围的人们在非高峰期出行时,公交系统的运营效率及运营成本与乘客等待公交时间的矛盾问题,本文提出了一种基于网约车思想利用手机APP实时预约公交的系统模式。在新请求出现时实时预约公交调度系统会先根据公交系统服务阈值筛选出符合条件的公交,再利用启发式最短路径算法为距离新请求点由近至远的公交依次进行响应路径规划,并结合响应判断函数计算对应公交的响应效益,然后指派首个效益为正的公交作为新请求的响应公交,最后调度系统会将响应公交的信息实时反馈到乘客APP。本文以重庆市外围地区的169路公交为研究对象,验证实时预约公交系统的可实施性,并得出该系统模式在城市外围非高峰期可以进一步完善公交运营系统且满足乘客出行需求。  相似文献   

8.
面向公交车辆优化调度的运行服务质量评测分析   总被引:3,自引:0,他引:3  
将人工智能方法引入公交车辆运营调度管理,调度管理人员可根据具体运营状况,运用快速、便捷的智能调度算法,制订出符合实际情况的运营调度方案,有效提高公交车辆运营效率。利用遗传算法(genetic algorithm,GA)的智能化特征,针对北京市公交车辆运营管理问题进行了优化调度研究。仿真实验表明,利用GA的公交车辆优化调度,实现了公交车辆调度的智能化,并在基础上利用排队论推导了乘客等待时间模式,进行了优化调度结果评测分析,从而验证了利用智能调度方法能够有效地改善公交车辆运营效率的合理性和可行性。  相似文献   

9.
严建清 《科技信息》2012,(31):275-275,198
公交运营调度是整个公交企业管理业务的核心,优化公交线路的发车频率,提高我国城市公交的运营调度水平,是改善城市公交服务质量、提高公交吸引力的重要途径。本文分别从公交乘客利益和公交企业利益角度分析了公交线路调度问题,建立了以企业满意率最高、乘客满意率最高为目标的公交车辆发车间隔优化模型,兼顾了乘客和企业的双方利益。  相似文献   

10.
利用灰关联理论的基本原理,建立公交智能调度评价模型.首先从乘客满意度、经济效益、调度技术水平3方面建立评价指标体系.然后,针对定量、定性指标采用不同的规范化处理方法,并计算指标的灰关联系数.考虑各指标在评价体系中的不同影响程度,确定指标权重值.通过逐层计算灰关联度并排序,分析不同调度方案的优劣.最后,以某公交线路为例,选取传统全程车调度、传统大站快车调度、公交智能化调度3种方案进行分析.计算结果表明,公交智能化调度方案的关联度达到0.938,明显优于其他2种方案.该评价方法切实可行,能够客观评价公交调度方案,从而进行方案决选.  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.
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   

15.
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   

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.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  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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