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Search Results: 1 - 10 of 22944 matches for " 尹嘉男 "
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多跑道机场停机位分配仿真模型及算法
,胡明华,赵征
交通运输工程学报 , 2010,
Abstract: 基于传统滑行路径和停机位等待的理念,建立了多跑道机场停机位分配仿真模型,在满足场面运行安全约束的条件下,寻求滑行时间最小的分配方案。通过多跑道机场的地面网络数据、运行模式以及航班计划等信息,利用计算机仿真对模型进行了算法设计,并对场面的实时运行状况进行了停机位分配的仿真模拟。仿真结果表明该算法与随机分配算法相比,多跑道机场的地面容量提高了4.6%,冲突探测与解脱的次数降低了10.7%,最大延误减小了34.8%,因此,机场场面的运行效率得到提高,所提算法有效。
多机场终端区进场航班协同排序方法
马园园,胡明华,张洪海,,吴凡
航空学报 , 2015, DOI: 10.7527/S1000-6893.2014.0280
Abstract: 为有效缓解大都市圈机场群日益严重的空域拥堵和航班延误现状,系统研究了多机场终端区进场航班协同排序问题。通过深入剖析多机场终端区时空运行特性,综合考虑移交间隔、尾流间隔和多跑道运行间隔等约束限制,科学权衡安全、经济和公平等各方利益需求,引入多元受限时间窗的创新理念,建立了多机场终端区进场航班协同排序模型。结合多目标优化及遗传算法基本理论,设计了带精英策略的非支配排序遗传算法,寻求多机场终端区进场航班协同排序问题的Pareto最优解。仿真实验表明,模型可对多机场终端区进场航班进行优化排序,显著降低航班延误总时间,有效增强多机场空域资源使用公平性。与经典的先到先服务(FCFS)策略相比,协同排序策略优化效果较为显著,其中航班延误时间减少了31.0%,所提方法可显著缓解大都市圈机场群航班延误现状,有效提升航空运输服务品质。
复杂终端区进场交通流优化排序方法研究
胡明华,马园园,田文,
南京航空航天大学学报 , 2015,
Abstract: 为提高终端区时空资源利用率,增强空中交通运行效率,研究了复杂终端区进场交通流优化排序问题。通过深入剖析终端区进场定位点、航路航线、多跑道系统等资源运行特性,综合考虑尾流间隔、移交间隔、多跑道运行间隔等各类约束限制,以及最小化航班延误时间、最大化跑道运行容量、最小化终端区飞行时间等优化目标,建立了复杂终端区进场交通流优化排序模型,并采用带精英策略的非支配排序遗传算法对所建模型进行求解。选取上海多机场组成的复杂终端区进行实例验证,仿真实验表明提出的优化方法相比先到先服务方法(firstcomefirstserve,fcfs),航班总延误时间减少20.7%,终端区等待时间减少60.7%,终端区进场交通流运行效率得到显著提升。
考虑周期性波动因素的中长期空中交通流量预测
Forecast Method for Medium-Long Term Air Traffic Flow Considering Periodic Fluctuation Factors

陈丹, 胡明华, 张洪海,
CHEN Dan
, HU Minghua, ZHANG Honghai, YIN Jianan

- , 2015,
Abstract: 摘要: 为准确把握空域单元交通流量的变化趋势和周期性波动规律,综合考虑气候、季节、交通需求等因素,通过分析中长期历史流量数据,在线性增长模型的基础上,建立了考虑周期性波动因素的空中交通流量动态线性改进模型,采用贝叶斯状态估计和预测方法对模型进行求解,提出了一种根据空域单元流量时序数据预测中长期流量及其变化趋势的预测方法.利用国内典型空域单元实际流量数据,对比分析了上述两种模型的预测性能.实例研究表明:与线性增长模型的预测结果相比,本文模型的流量预测结果更符合我国的实际情况,反映了流量周期性波动特点,年流量预测结果的平均绝对误差从3.14%下降到了1.71%,预测误差的标准差从2.01%下降到了0.02%.
Abstract: To accurately characterize the trend and periodic fluctuation of the future traffic demand in a specific airspace unit, an improved dynamic linear model that is based on the linear growth model was developed to forecast the medium-long term air traffic flow, by taking into full account periodic fluctuation factors such as the climate influence, seasonal fluctuation, actual traffic demand, and so on. Then, the Bayesian state estimation and forecasting method was used to solve the proposed model, and the medium-long term air traffic flow and its variation trend was predicted using the historical data of air traffic flow in a specific airspace unit. In addition, a case study on a real data set of a typical domestic airspace unit was carried out to compare the forecasting performance of the models. The results show that, compared with the linear growth model not considering periodic fluctuation factors, the air traffic flow obtained by the improved model has a periodic fluctuation characteristic, and is more in line with the real situation of air transportation in China; simultaneously, the mean absolute error of the yearly traffic flow decreases from 3.14% to 1.71%, and the standard deviation of forecast error decreases from 2.01% to 0.02%
基于贝叶斯估计的短时空域扇区交通流量预测
Short-Term Traffic Flow Prediction of Airspace Sectors Based on Bayesian Estimation Theory

陈丹, 胡明华, 张洪海,
CHEN Dan
, HU Minghua, ZHANG Honghai, YIN Jianan

- , 2016, DOI: 10.3969/j.issn.0258-2724.2016.04.028
Abstract: 为准确把握空域扇区流量分布态势及未来变化趋势,提出了一种基于贝叶斯估计的短时空域扇区交通流量预测方法.首先,通过解析空域系统内航空器原始雷达数据,提取各扇区历史运行信息,建立了多扇区聚合交通流模型;其次,采用贝叶斯估计理论对模型参数进行最优估计和动态更新,预测了空域扇区交通流量的未来演变趋势及其不确定范围;最后,选取国内5个典型繁忙扇区为例,以5 min为时间段,以未来1 h为预测范围,对所提预测方法进行了验证.研究结果表明85%以上时段交通流量预测结果的绝对误差在3架以内,平均绝对误差均在2架次以内,预测结果的稳定性较好,可充分反映各空域扇区之间短时交通流的动态性和不确定性,符合空中交通的实际情况.
: To accurately forecast the air traffic flow distribution in airspace sectors and its development trend in the future, a short-term traffic flow prediction method based on Bayesian estimation theory is proposed. First, the operational history data of various sectors in the airspace system are extracted by parsing raw radar data of the aircraft within the airspace system. On this basis, an aggregate multi-sector traffic flow model is established. Then, Bayesian estimation theory is adopted to predict the future trend of airspace sector traffic flow and its uncertainty intervals by estimating and updating the optimal parameter of the aggregate multi-sector traffic flow model dynamically. Finally, the proposed method is verified on a set of operational history data of five air route sectors, taking 5 min as one time step to predict the short-term air traffic flow in the next one hour. The results show that the absolute error of the predicted results of more than 85% time steps is less than 3, the average absolute error is less than 2, and the stability of the predicted results is well. The proposed method can adequately reflect the dynamics and uncertainty in the airspace system operation, and hence is well in line with the practice
公共价值管理:西方公共管理发展的新动向

天府新论 , 2009,
Abstract: 在新公共管理时代之后,建立在公共部门战略管理、新公共服务理论和网络化治理理论基础上的公共价值管理理论应运而生。公共价值管理理论主张,公共管理者应该寻找并创造公共价值,拓展公众参与,建立开放型的、灵活的公共服务获取和递送机制。与传统公共行政理论和新公共管理理论相比,公共价值管理具有重要实践意义:使公共管理者更具战略思维,重新审视管理过程中的政治,使政府的合法性更有保障,民主和效率的矛盾得到解决。
多视点分布式视频编码的研究
林昕??,刘海涛??,
哈尔滨工程大学学报 , 2010,
Abstract: 随着新型多媒体传感器网络的出现,现有编码方法不能有效适应其庞大的数据量.因此针对多媒体传感器网络能量、资源受限的问题,该文研究能提供低复杂度、低能耗、低成本编码器的分布式视频编码技术.文章总结了多视点分布式视频编码各个环节的最新研究进展,并针对分布式视频编码的核心内容边信息生成,提出了基于多视图几何的空间边信息生成算法,又在此基础之上应用线性组合模型的融合算法使边信息质量进一步提高.仿真结果表明,空间边信息生成算法可以使率失真性能得到2 dB左右的提高,而线性组合模型的融合方法可以使增益再提高0.3 dB左右.
基于缓解公交列车化现象的最小发车间隔研究
,罗霞,黄启乐,魏强
重庆交通大学学报(自然科学版) , 2012, DOI: 10.3969/j.issn.1674-0696.2012.04.25
Abstract: :?在分析公交列车化现象及其产生原因的基础上,从考虑约束发车间隔下限出发,以缓解公交列车化现象为约束条件,以公交企业运营成本最小和乘客利益最大为目标函数,探讨了公交车最小发车间隔的确定方法。用成都市81路公交车调查数据验证了该模型的可行性和有效性。
平纹织物三维细观几何模型和织物防弹实验的有限元模拟
王东宁,,焦亚
材料工程 , 2013, DOI: 10.3969/j.issn.1001-4381.2013.09.014
Abstract: 建立了平纹织物的三维细观几何模型,利用LS-DYNA有限元软件模拟了弹丸冲击的条件下,单层芳纶织物的响应过程。模型的几何形状参考了平纹织物的截面显微镜照片,使建立的模型更加准确,更接近平纹织物真实的结构。纱线模型选用正交各向异性材料,材料参数和失效条件均参考真实的Kevlar织物,并考虑纱线和纱线之间以及纱线和弹丸之间的摩擦。模拟中,通过设定弹丸的撞击速率Vs,得到剩余速率Vr,并由此计算单层织物的弹道极限速率V50。结果表明织物的变形过程和失效形式在模拟中得到细致的显现,模拟所得结果V50和织物的失效形式与实验结果的一致程度较好。
熟制中华绒螯蟹在冻藏过程中的品质变化
施祁燕,王锡昌,
上海海洋大学学报 , 2017, DOI: 10.12024/jsou.20170402028
Abstract: 为了研究中华绒螯蟹在冻藏期间的品质变化,通过感官和理化指标判断冷冻蟹膏蟹黄和蟹肉的赏味期分别为180 d和240 d;180 d时蟹膏蟹黄腥味和油耗味过重,蟹肉在240 d时不被接受是由于氨味和腥味过重;使用固相微萃取(solid-phase microextraction,SPME)和气相色谱质谱联用仪(gas chromatography-mass spectrometer,GC-MS)萃取并检测中华绒螯蟹在冻藏期间的挥发性气味物质,利用气味活性值(odor activity value,OAV)筛选发现中华绒螯蟹在冻藏过后对气味影响最主要的物质是苯甲醛、壬醛、2,6-壬二烯醛、1-辛烯-3-醇、2,4-癸二烯醛和三甲胺。
To study the quality change of Chinese mitten crab during the frozen storage, sensory and physical and chemical indicators were used to judge the taste period of 180 days of gonad part and 240 days of meats. Fishy smell and rancidodor in the gonad part of crabs were too heavy after 180 days.Crabmeat was not accepted after 240 days because of the ammoniacal smell and fishy smell. The volatile odor substances of Eriocheir sinensis were extracted and detected by Solid-phase microextraction (SPME) and Gas Chromatography-mass Spectrometer (GC-MS) before and after freezing. The compounds were analyzed and selected by odor activity value (OAV). The results showed that the most important substances affecting the odor of Eriocheir sinensis after freezing were Benzaldehyde, Nonanal,2,6-Nonadienal, 1-Octen-3-ol, 2,4-Decadienal and Trimethylamine.
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