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1.
Given that the fixed air traffic operation system and functions are difficult to adapt to the great changes of air route structure and airspace demand, the airspace resource allocation is undergoing an evolution from static to flexible and dynamic so as to effectively solve the contradiction between airspace capacity and actual demand. In this process, the dependence on spatiotemporal continuous data is gradually strengthened. This article reviewed the relevant national and international research, and found that from the multi-dimensional expression of basic elements to the feature analysis of specific airspace units, airspace resource allocation deepens and expands in a real-time direction and presents a new mechanism. A series of high density air traffic flow identification methods are developed by introducing time parameters and combined with the flight path model to form a distinct dynamic characteristic. Related applications and practice reflect the structural revolution of airspace resource allocation and promote the solution of practical problems such as airspace congestion and resource allocation. The research and practice of dynamic airspace resource allocation outside China have positive reference significance to our country. However, when simultaneously coping with the hoisting of airside capability and the change of multi-dimensional parameters, we still face the challenges of period-segment matching, micro-macro combination, terminal airspace-air route docking and airspace-land area integration. In the future, geography should further integrate the unique advantages of spatiotemporal interaction and construct a brand-new overall mobile chain of various airspace-land scales to carry out research work deeply.  相似文献   

2.
Du Xinru  Lu Zi 《地球科学进展》2016,31(3):269-276
The application of ICTs makes structural change of the development and effective utilization of airspace. Next generation air transportation system (NextGen) includes new automation concepts with automated information to support the traffic control decision-making. As a result, in the field of academia and industry, air traffic controllers integrate information automatically while making decisions to change the previous manually integrated and decided pattern. The safety ability of airspace is reduced and airspace system is endangered under risky weather conditions of airspace. So there is an urgent demand for new information and communication technologies. The paper is an overview of the information constitution and support of NextGen and provides the study of the development of technique of airspace collaborative decision-makings to confirm the new features based on ICTs. It contains basic application-the input of data and output of the routes of airspace management and collaborative decision-making, and general application-the choose of probability nets of avoiding risky weather, and special application-the affection in the management of the air routes, which are made up of position and direction. The research shows the accurate schedule characteristics of airspace management and collaborative decision-making based on ICTs, which made the space accurate by time accurate. Second, the visualization of airspace management and collaborative decision-making based on ICTs made the maps of flight path under mobile data quickly generated. This could make the fully development and utilization of national airspace, ensure safety, and reduce air traffic controllers’ workload and the costs in delaying and operating in risky weather.  相似文献   

3.
The flexible use of airspace and its practice are the key components of next generation air transportation system and the important technical support of reconstructing the national airspace in Europe, Japan and other countries. On the basis of overview and comprehensive cognition of the generation, implementation and aims of flexible use of airspace, the design methods of sector’s boundary changes were evaluated. Then, from the perspective of “sector-closed”, the effect on sector boundary changes was evaluated, and the time alternative mechanism in flexible use of airspace was revealed. The research shows that “Algorithm+Manual Dynamic Boundary Change” can be a method for better distribution and balancing the unbalanced traffic demand across regions, which will also promote the airspace development and capacity release. The flexible use of airspace based on ICTs realizes the replacement of the factor of space by the factor of time, which enhances the flexibility of airspace configuration and the changing of air routes to the maximun extent. The methods and applications of flexible use of airspace will be not only beneficial to establishing the whole national airspace system and utilization, but also to promoting geography research on airspace resources development and the studies on connection between air and land.  相似文献   

4.
Bai Long  Lu Zi  Du Xinru  Gao Fang 《地球科学进展》2016,31(11):1197-1204
The exploitation of (ultra) low airspace resource has become an important component of optimizing the utilization of airspace and has received worldwide attention. It is the major form for UAV activity, which reveals great socioeconomic prospects. Firstly, the background of exploiting (ultra) low airspace resource and challenge for UAV activities were analyzed in regional areas. Then, legal rights for UAV activities and routes design in overseas and domestic research were reviewed. Second, the forms of regional rules for UAV activities in (ultra) low airspace were summarized, which included height-density rule, coverage area rule and isolation area of rule. Third, based on the air network of UAV(s) and aiming at the demand of aerial lanes for different requirements, the development from the method of 3D city model to the Cost-to-go was prospected. The findings are as follows: UAV activities’ aerial lanes design includes high-density as general rules and coverage area rule, isolation area rule as special rules. On the basis of 3D city model, improved method of Cost-to-go is applied to the choice of the optimal aerial lanes; based on ground buildings and residents’ actual conditions in regional area, the rules and methods are good for the (ultra) low airspace resources development and better solve the problem of UAV activities coordination. Furthermore, the rules and methods play an important role even in the implementation of the national airspace system.  相似文献   

5.
国外空域资源开发利用的理论基础、方法论变革与实践   总被引:3,自引:1,他引:2  
Lu Zi  Du Xinru 《地球科学进展》2015,30(11):1260-1267
空中交通流量的持续增长引发充分开发利用空域资源的理论建设和方法论研究及其应用实践,旨在突破原有的空域结构及其扇区边界的限制。在过去的10年里航线结构及其需求有了显著变化,仍保持相对固定的几何扇区形态面临新的挑战,需要重新设计动态空域功能分区。首先分析了当前空域资源开发利用的理论基础,包括新一代航空运输体系,灵活空域使用,平衡扇区等;然后评价了方法论的变革,总结了从动态空域配置(DAC)到动态空域功能分区(DAS)的转变,以及动态空域功能分区的2D-DAS常用方法向3D-DAS新方法的演进,并讨论了"基于个体模型"(ABM)的局限性和"改进的基于个体模型"(i ABM)的应用优势;最后展望了地理学空间研究向空域拓展的前景。  相似文献   

6.
最短路径分析是交通网络分析系统的一个基本问题,在理论上得到了广泛深入地研究.本文研究的目的是将理论分析应用于实践,主要利用NetEngine的网络分析功能来实现最短路径的分析,并在电子地图上显示路径.在开发首都国际机场应急救援与辅助决策系统的过程中,基于MapObjects2,NetEngine,利用Visual Basic来实现任意两点间最短路径分析功能,为首都机场的应急救援决策支持工作提供了最短路径信息,实践表明该方法简单、实用.  相似文献   

7.
放射性生热率是岩石热物性参数之一,也是研究岩石圈热结构和构造热演化的重要参数。针对南海海盆区缺少岩石生热率资料的实际情况,本文通过整理和分析IODP349航次中的测井资料,测试钻井岩心样品的主要放射性生热元素,通过计算得出:玄武岩样品的生热率平均值为0.28±0.07μW/m~3,沉积碎屑岩样品的生热率为1.21±0.34μW/m~3,以及3个钻井的地热流值。获得以下认识:(1)本次研究的沉积碎屑岩样品生热率与中国东南沿海的同类岩石样品的生热率值相近,而洋壳中的基性火山岩生热率明显低于大陆碱性玄武岩。(2)用新资料计算南海西南次海盆段的岩石圈热结构得出其热岩石圈厚度约为39~42 km,平均壳幔热流比值为2.4%,说明西南次海盆岩石圈薄,海底热流主要受深部的地幔热源控制。(3)U1431D和U1433A钻井的热流密度值与附近探针热流密度值相近;而U1431C的热流密度值明显偏小,属于受地下水热循环影响所致。  相似文献   

8.
粘性土为主的地基强夯的时效性   总被引:1,自引:0,他引:1  
根据浦东国际机场飞行区跑道地基强夯工程(三标)实测的不同时间的静力触探资料,讨论以粘性土为主的地基强夯强度增长的时效现象,得出:粘性土为主的地基,强夯的加艇具有滞后特性。  相似文献   

9.
冻土温度状况研究方法和应用分析   总被引:12,自引:6,他引:6  
李述训  吴通华 《冰川冻土》2004,26(4):377-383
分析讨论了冻土温度状况研究中相关问题,包括构成多年冻土层的岩性、含水量、结构和构造,决定多年冻土温度状况动态变化的地面温度与气温间的关系,地中热流,研究区域的确定以及取决于地层的岩性、含水量、结构和构造、容重的热量在地层内传播过程的热物理参数.在分析物理学、地学和气候学等学科研究结果的基础上,笔者认为:1)在研究冻土温度状况问题中,研究区域应根据所研究问题的时间尺度确定,由于多年冻土层内不同深度上的温度和热流(或温度梯度)随时间的不同影响深度也不同,研究数十年时间尺度的多年冻土温度状况问题,一般应取多年冻土下限处的地中热流(或温度梯度)作为问题的下边界条件;2)以气温积温(或气温)与地面温度积温(或地面温度)比值所定义的N系数不仅存在年变化、季节变化和日变化,并在求解时必须已知地面冻结(或融化)的持续时间,而在目前对于不同地面条件缺乏定量描述气温与地面温度间关系的实验基础.因此,在缺乏比较严格的地面条件定量描述的情况下,应用气温与地面温度之差描述二者间的关系可能更为简单;3)在青藏高原地区,由于不同区域地形、地面条件、地层岩性以及地中热流等存在着很大差异,因而,不同区域多年冻土的热状况也不同.所以,不能简单地以气温等值线进行多年冻土制图,更不能以此年冻土变化预报的基础.  相似文献   

10.
The contradiction between the rapid development of aviation market and supply of airspace resources has increased the environmental damages of aviation carbon emission. The conversion and application of environmental damage assessment method of aviation carbon emission were summarized, and the characteristics of the assessment methods for air and ground transportation were compared. We found out the followings: The evaluation method has been transformed from static assessment to dynamic evaluation, and focused on four key problems, average and total carbon emissions, airspace resource utilization, LTO stage emission, and reduction practice; Airport terminal area as well as LTO are becoming the focus in the study of aviation carbon emission assessment method, while the former is the main area and the latter is the main stage of aviation carbon emission. The practice of emission reduction is mainly reflected in the optimization of emission reduction measures in economic field; Based on the situation and total assessment methods, environmental damage assessment and comparative advantage of aviation carbon emission and ground transportation carbon emission are reflected in the distance by using distance factor and energy consumption; Improving the smoothness of airspace resource traffic network, optimizing flight schedule structure and airspace resource allocation are more conducive to promoting aviation emission reduction.  相似文献   

11.
Volcanic hazards to airports   总被引:3,自引:1,他引:2  
Volcanic activity has caused significant hazards to numerous airports worldwide, with local to far-ranging effects on travelers and commerce. Analysis of a new compilation of incidents of airports impacted by volcanic activity from 1944 through 2006 reveals that, at a minimum, 101 airports in 28 countries were affected on 171 occasions by eruptions at 46 volcanoes. Since 1980, five airports per year on average have been affected by volcanic activity, which indicates that volcanic hazards to airports are not rare on a worldwide basis. The main hazard to airports is ashfall, with accumulations of only a few millimeters sufficient to force temporary closures of some airports. A substantial portion of incidents has been caused by ash in airspace in the vicinity of airports, without accumulation of ash on the ground. On a few occasions, airports have been impacted by hazards other than ash (pyroclastic flow, lava flow, gas emission, and phreatic explosion). Several airports have been affected repeatedly by volcanic hazards. Four airports have been affected the most often and likely will continue to be among the most vulnerable owing to continued nearby volcanic activity: Fontanarossa International Airport in Catania, Italy; Ted Stevens Anchorage International Airport in Alaska, USA; Mariscal Sucre International Airport in Quito, Ecuador; and Tokua Airport in Kokopo, Papua New Guinea. The USA has the most airports affected by volcanic activity (17) on the most occasions (33) and hosts the second highest number of volcanoes that have caused the disruptions (5, after Indonesia with 7). One-fifth of the affected airports are within 30 km of the source volcanoes, approximately half are located within 150 km of the source volcanoes, and about three-quarters are within 300 km; nearly one-fifth are located more than 500 km away from the source volcanoes. The volcanoes that have caused the most impacts are Soufriere Hills on the island of Montserrat in the British West Indies, Tungurahua in Ecuador, Mt. Etna in Italy, Rabaul caldera in Papua New Guinea, Mt. Spurr and Mt. St. Helens in the USA, Ruapehu in New Zealand, Mt. Pinatubo in the Philippines, and Anatahan in the Commonwealth of the Northern Mariana Islands (part of the USA). Ten countries—USA, Indonesia, Ecuador, Papua New Guinea, Italy, New Zealand, Philippines, Mexico, Japan, and United Kingdom—have the highest volcanic hazard and/or vulnerability measures for airports. The adverse impacts of volcanic eruptions on airports can be mitigated by preparedness and forewarning. Methods that have been used to forewarn airports of volcanic activity include real-time detection of explosive volcanic activity, forecasts of ash dispersion and deposition, and detection of approaching ash clouds using ground-based Doppler radar. Given the demonstrated vulnerability of airports to disruption from volcanic activity, at-risk airports should develop operational plans for ashfall events, and volcano-monitoring agencies should provide timely forewarning of imminent volcanic-ash hazards directly to airport operators.  相似文献   

12.
G. H. Pirie 《GeoJournal》1990,22(3):231-240
The geography of air transport to and from South Africa has been shaped powerfully by the world map of anti-apartheid, sanctions-keeping nations which close their airspace to the Republic's state-owned airline. Re-routering, involving notably the offshore west-African link to Europe, revocation of foreign landing rights and a shrinking airline network have resulted. The economic dependence of the Republic's southern African neighbours on their political adversary has dissuaded them from joining an anti-apartheid air blockade. Likewise, the penalties to black African states of denying overfying, landing and traffic rights to west-European airlines plying the South Africa route have diminished the force of the air embargo.  相似文献   

13.
热流和岩石生热率关系的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
赵平  汪缉安 《地质科学》1996,31(3):297-307
通过花岗岩体和中下地壳剖面岩石生热率的研究,显示出花岗岩体内生热率的分布至多样性;华北下地壳变质岩的生热率介于0.2-0.4μW/m3之间,其对热流的热贡献较小;地壳岩石生热率总体上是深度不连续的递减函数。中国东南地区出露着大面积的中生代花岗岩体,实测热流和岩石生热率没有得出可信的线性关系。结合对现有热流省资料的认识,提出了对热流和岩石生热率关系的新看法,解释了以往线性关系的不稳定性,估算出正常陆壳厚度的热流下限应为29.5mW/m2。  相似文献   

14.
The effective elastic thickness (Te) represents the thickness of the elastic layer or the flexural rigidity of the lithosphere, the equivalent of which can be calculated from the spectral analysis of gravity and topographic data. Studies of Te have profound influence on intracontinental deformation, and coupling of the tectonic blocks. In this paper, we use the multitaper spectral estimation method to calculate the coherence between Bouguer gravity and topography data, and to obtain the Te map of South China. Through the process of correction, we discuss the relationships of Te versus heat flow, and Te versus seismicity. The results show that Te distribution of South China is affected by three factors:the original age, which controls the basic feature;the Mesozoic evolution, which affects the Te distribution;and the neotectonic movement, which shaped the final distribution. The crust age has a positive correlation with the first-order Te distribution;thus the Yangtze Craton has a relatively higher Te (about 50 km) whereas the Te in Cathaysia block is only 10e20 km. By analysis and comparison among the tectonic models of South China, the Te distribution can be well explained using the flat-subduction model. As is typical with neotectonics, the region with a higher heat flow is related with a lower Te. The seismicity does not have a clear relationship with Te, but the strong seismicity could cause a low Te. Seismogenic layer (Ts) has a similar trend as Te in the craton, whereas in other areas the relationship is complex.  相似文献   

15.
确定中、新生代沉积盆地大地热流的方法   总被引:1,自引:1,他引:1       下载免费PDF全文
陈墨香 《地质科学》1989,(2):151-161
用传统的方法于年青的沉积盆地测试大地热流,存在的问题多且难度大,因而这些盆地一直是世界热流测试研究最薄弱的地区之一。本文在符合热流测试原理的前提下,尝试用一种较容易确定热流值的方法,虽然这种方法获得的数据是近似值,但是可以接受的,并有地质、地球物理意义。也简要论述在新生界盖层地温梯度图的基础上,确定一个合理的系数,即盖层的平均热导率值,将地温梯度图转换为热流图,用以反映盆地地热的基本面貌。  相似文献   

16.
北京市水源热泵的应用,宏观上未充分考虑地下水水源地的分布,微观上未注重应用场地的水文地质条件,地下水回灌率低造成了水资源浪费。本文针对北京平原区的水文地质条件,以浅层含水层导水系数、有效导水系数、地下水中的铁和总硬度为评价因子,以水源地保护区及补给区、地面沉降中心区为约束因子,利用叠加分析技术,将平原区分为适宜发展区、较适宜发展区、限制发展区和禁止发展区,为水源热泵的理性推广提供了技术参考。  相似文献   

17.
An updated analysis of geothermal data from the highland area of eastern Brazil has been carried out and the characteristics of regional variations in geothermal gradients and heat flow examined. The database employed includes results of geothermal measurements at 45 localities. The results indicate that the Salvador craton and the adjacent metamorphic fold belts northeastern parts of the study area are characterized by geothermal gradients in the range of 6–17°C/km. The estimated heat flow values fall in the range of 28–53 mW/m2, with low values in the cratonic area relative to the fold belts. On the other hand, the São Francisco craton and the intracratonic São Francisco sedimentary basin in the southwestern parts are characterized by relatively higher gradient values, in the range of 14–42°C/km, with the corresponding heat flow values falling in the range of 36–89 mW/m2. Maps of regional variations indicate that high heat flow anomaly in the São Francisco craton is limited to areas of sedimentary cover, to the west of the Espinhaço mountain belt. Crustal thermal models have been developed to examine the implications of the observed intracratonic variations in heat flow. The thermal models take into consideration variation of thermal conductivity with temperature as well as change of radiogenic heat generation with depth. Vertical distributions of seismic velocities were used in obtaining estimates of radiogenic heat production in crustal layers. Crustal temperatures are calculated based on a procedure that makes simultaneous use of the Kirchoff and Generalized Integral Transforms, providing thereby analytical solutions in 2D and 3D geometry. The results point to temperature variations of up to 300°C at the Moho depth, between the northern Salvador and southern São Francisco cratons. There are indications that differences in rheological properties, related to thermal field, are responsible for the contrasting styles of deformation patterns in the adjacent metamorphic fold belts.  相似文献   

18.
This work deals with 2D thermal modeling in order to delineate the crustal thermal structure of central India along two Deep Seismic Sounding (DSS) profiles, namely Khajuriakalan–Pulgaon and Ujjan–Mahan, traversing the Narmada-Son-Lineament (NSL) in an almost north–south direction. Knowledge of the crustal structure and P-wave velocity distribution up to the Moho, obtained from DSS studies, has been used for the development of the thermal model. Numerical results reveal that the Moho temperature in this region of central India varies between 500 and 580 °C. The estimated heat flow density value is found to vary between 46 and 49 mW/m2. The Curie depth varies between 40 and 42 km and is in close agreement with the Curie depth (40±4 km) estimated from the analysis of MAGSAT data. Based on the present work and previous work, it is suggested that the major part of peninsular India consisting of the Wardha–Pranhita Godavari graben/basin, Bastar craton and the adjoining region of the Narmada Son Lineament between profiles I and III towards the north and northwest of the Bastar craton are characterized with a similar mantle heat flow density value equal to 23 mW/m2. Variation in surface heat flow density values in these regions are caused by variation in the radioactive heat production and fluid circulation in the upper crustal layer.  相似文献   

19.
抗浮设防水位直接影响到地下结构的安全与建设费用,在地下结构建设中至关重要,因此,科学合理地确定地下结构的抗浮设防水位具有巨大的社会意义和经济价值。本文以“雄安新区至北京大大兴国际机场快线地下工程段”为研究对象,系统分析了研究区水文地质条件以及地下水位年内年际动态变化规律,利用数值模拟法和类比预测法确定了地下结构抗浮设防水位标高建议值。结果表明,该场地区域浅层地下水水位埋深一般为5.0~20.0m,地下水水位标高一般为–10.0~1.0m。近五年场地浅层地下水水位标高一般为–5~–10 m,埋深一般为3.0~15.0 m,地下水位逐年升高,回升速率约1.0 m/a。地下结构抗浮设防水位标高取值建议取使用期抗浮设防水位采用数值模拟法预测结果。该成果服务了“雄安新区至北京大兴国际机场快线(R1线)”项目场地抗浮设计,为雄安新区重大工程建设项目的抗浮安全设计提供了示范。  相似文献   

20.
The behaviour of the Pleistocene Osaka clays at Kansai International Airport Phase 1 island is investigated by FEM analyses using an elasto-viscoplastic constitutive model which replicates the destruction processes occurring in the microstructure of the clay. Excellent predictions are obtained by 2D analyses carried out using the actual soil profile and the characteristic values of soil parameters, confirming the validity of the methods proposed for characterizing and modelling structured clays. Unlike 1D analyses, where partially effective drainage layers occur, 2D analyses do not require arbitrary pre-definition of the model drainage scenario and of the ‘equivalent’ permeability of interlayered clays to account for macrostructure. In these conditions, 1D analyses must be validated with reference to 2D or 3D prototype analyses and/or well documented experience of comparable work. Once thus validated, 1D analyses are used to investigate the relative merits of possible measures (relief wells, preloading, lightweight fill) aimed at reducing in-service settlement. For future reclamation works at sites where structured clays extend to great depth, filling with lightweight material shows the greatest promise, but it is unlikely to remove the need for designing the superstructure to accommodate the inevitable settlement, which requires accurate prediction.  相似文献   

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