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1.
The calculation of air passenger flow density and the recognition of heat airspace in terminal areas of large hub airports is a new challenging research in the intelligent era, that is, using big data can automatically generate air passenger flow and basic rules. Aimed for the air passenger flow density in airport and its relationship between occupation and airspace, based on the establishment of the Beijing International Airport 1 h flight, which consists of basic parameters-latitude, longitude and height, additional parameters-dogleg and speed of trajectories, time parameters, a spatio-temporal data set by clustering trajectories and calculation of aircraft trajectories points was made up. Then, heat cloud map of flight trajectories under 4D conditions was generated. Cell was used to identify the basic parameters and time parameter of heat airspace; grid graphs of flight trajectories were used to identify additional parameters and explain the influence on heat airspace; probability fitting graphs were used to verify the accuracy of 4D results. The conclusion is as follows: there are two areas of Beijing International Airport, which have the high density and at two different heights there also exist hot peaks; flight trajectories and speed of trajectories also affect the heat airspace. The variation of heat airspace caused by different flight occupancy time in 4D recognition was revealed. The method realized the 4D heat cloud map of flight trajectories, which is better for detailed and accurate information construction, expression of spatial changes, and more the parameters of density and visualization of temporal and spatial range, which can assist the automatic dynamic airspace sectorization and decision making on airspace allocation, and also have a definite reference meaning in alleviating the contradiction between the current air traffic demand and limited airspace.  相似文献   

2.
多年冻土地区机场跑道修筑技术现状   总被引:3,自引:0,他引:3  
刘伟博  喻文兵  陈琳  易鑫  韩风雷  胡达 《冰川冻土》2015,37(6):1599-1610
我国分布有大面积的多年冻土, 根据我国机场建设的中长期规划, 未来将在多年冻土区修建大量机场, 这些机场的修建将不能避免多年冻土问题. 国内关于冻土区机场跑道修筑的经验非常有限, 国外则开始的较早, 并积累了一些经验. 总结分析国内外多年冻土区机场跑道修筑技术的现状, 其跑道类型主要有: 基岩跑道、开挖换填法修筑的跑道、铺设隔热层的跑道、安装热管的跑道, 共4类. 由于我国多年冻土区的特殊性, 国外的跑道修筑经验只能在一定程度上参考. 由于飞机跑道不同于铁(公)路的特殊性, 近年国内在冻土区铁(公)路的修建过程中采用的稳定冻土地基的工程措施如何应用到机场跑道的建设上, 仍需进一步研究、验证和实践. 将来在我国多年冻土区修建机场跑道, 应结合国外已有的技术和经验, 并以我国在多年冻土区线性工程中已取得的经验作为基础, 进一步研究我国多年冻土区机场跑道修筑的关键技术.  相似文献   

3.
In recent years, uses of high-resolution population distribution databases are increasing steadily for environmental, socioeconomic, public health, and disaster-related research and operations. With the development of daytime population distribution, temporal resolution of such databases has been improved. However, the lack of incorporation of transitional population, namely business and leisure travelers, leaves a significant population unaccounted for within the critical infrastructure networks, such as at transportation hubs. This paper presents two general methodologies for estimating passenger populations in airport and cruise port terminals at a high temporal resolution which can be incorporated into existing population distribution models. The methodologies are geographically scalable and are based on, and demonstrate how, two different transportation hubs with disparate temporal population dynamics can be modeled utilizing publicly available databases including novel data sources of flight activity from the Internet which are updated in near-real time. The airport population estimation model shows great potential for rapid implementation for a large collection of airports on a national scale, and the results suggest reasonable accuracy in the estimated passenger traffic. By incorporating population dynamics at high temporal resolutions into population distribution models, we hope to improve the estimates of populations exposed to or at risk to disasters, thereby improving emergency planning and response, and leading to more informed policy decisions.  相似文献   

4.
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   

5.
Determination of xenobiotics in samples of airport runoff water is both a complex and indispensable task due to an increasing threat resulting from the activities of numerous airports. The aim of this study was to develop, optimize, and validate a procedure based on liquid–liquid extraction (LLE) coupled with gas chromatography–mass spectrometry (GC–MS) for the determination of polycyclic aromatic hydrocarbons (PAHs). So far, no procedure was available that would ensure reliable data about concentration levels of these toxic pollutants in a new type of environmental samples, such as airport stormwater. The most difficult step in the analytical procedure used for the determination of fuel combustion products in airport stormwater samples is sample preparation. In this work, eight different protocols of sample preparation were tested. The evaluation of the LLE demonstrated that the best extraction conditions were as follows: dichloromethane (extraction solvent), solvent volume of 15 mL and sample volume of 250 mL. The percent recovery values ranged from 66 to 106 %, which shows that the LLE technique is a powerful method for extracting PAHs from airport runoff water samples with a complex matrix composition. Moreover, the developed procedure was characterized by satisfactory selectivity and a relatively low LOQ (0.17–0.52 μg/L). The procedure has been successfully applied to the analysis of stormwater samples collected from different sites at international airport in Poland. The procedure can thus be used as a tool for tracking the environmental fate of these compounds and for assessing the environmental effect of airports.  相似文献   

6.
Urban sprawl in South America has for many decades been driven by the housing debate, with major impact on overall urban development. The impact of uncontrolled expansion has been social, economic and environmental degradation to high rates of poverty, poor services and transport. The presence of undeveloped areas within suburban landscapes, such as former infrastructural facilities, obsolete airports, and abandoned train stations, contribute to the impetus to reclaimed and revamped land. These spaces also trigger political aspirations for implementing better practices on “smart” growth, sustainable development and urban regeneration principles. A case in point is the former airport ‘Aeropuerto Cerrillos’ in Santiago, Chile, which closed in 2001 after years of decay; it intended to replace and host a large-scale urban project called ‘Ciudad Parque Bicentenario’. This development is still incomplete and describes a series of pressures on a planning system traditionally adjusted to promote expansion confirming that urban sprawl is still an open agenda triggered by the presence of diverse unexpected urban gaps.  相似文献   

7.
This paper analyses the potential for social integration in post-apartheid urban South Africa by examining the lives of those already living in desegregated spaces. The case study is a low-cost state-assisted housing project situated in the wealthy southern suburbs of Cape Town. In this social housing project, named Westlake village, coloured and Black African (alongside a handful of white and Indian) residents were awarded state housing in 1999 as replacement for their previous homes (informal and formal), which were demolished to make way for a mixed land-use development, of which their new homes form a small component. Westlake’s desegregation is found to extend beyond mere residential abode, affecting resident’s everyday lives to the extent that apartheid’s history and geography are superseded by other factors (such as proximity and affordability) in decision-making. Furthermore, integration at the everyday level of informal neighbourly mixing is prevalent. Although more formal cross-race friendships are rare, discussion reveals this as a consequence of Westlake’s specific socio-historic identity rather than racial divisions per se. Empirical evidence is used to propose a continuum of social integration experience. This continuum addresses the form of integration, for example greeting in the street, visiting homes, inter-marriage; and also the spaces of integration, for example physical space (shared neighbourhood), economic space (common employment-type), social space (cross-race friendship), political space (common involvement in civic organisations) and cultural space (shared sense of belonging).  相似文献   

8.
康定机场地基土特征及其形成机制   总被引:4,自引:1,他引:4  
拟建的康定机场位于青藏高原东缘、北西向展部的折多山的南西麓,控制标高4232.5m,是仅次于西藏邦达的世界 第二高机场。折多山由一花岗岩基组成,两侧被宽4~5km的巨型第四系坡积裙包围,康定机场位于其南西侧坡积裙上。坡 积裙的岩屑主要是通过崩滑脱离山体的,其演化趋势是完全覆盖折多山。除块石土、碎石土、角砾土及砂土外,地基土中还存 在一种由粒径30~100cm、次圆~次棱角状、表面粗糙的块石组成的特殊块石土,它在平面上有石窝、石窝群、石河及 石海等分布形式,垂向分布深度小于2m,其显著的自沉降现象对跑道稳定具有重要影响。特殊块石土是演化到一定程度 的坡积物经潜蚀作用形成的。四类正常土体及特殊块石土均属良好地基,潜蚀是导致其工程特性劣化及沉降的主要因素,地 基排水是今后工程施工的重点。  相似文献   

9.
Designing appropriate post-disaster emergency and recovery housing policies requires accurate estimation of the indirect or “flow” loss generated by the involuntary displacement of households to housing other than their own destroyed homes. We employed the stated choice method to measure residence choice following a hypothetical disaster in a procedure developed to estimate flow loss due to house destruction. This method was applied to households in the city of Nagaoka in Niigata Prefecture to estimate flow loss for a range of residence types and residence attributes following relocation. The results revealed that the relocation residence type itself (such as a shelter, temporary dwelling, rental housing, or one’s own home) had a substantial effect on residence choice. Regarding residence attributes, residential expenses such as rent, housing loans, and spaciousness had a significant effect on residence choice. Moreover, we found that respondents placed a very high value on living in their own home compared with other residence types, indicating that subsidizing the prompt repair and rebuilding of private homes is likely to be an effective recovery support policy. In addition, a cost–benefit analysis of our results revealed that rent subsidies are more efficient than the construction of public housing as a means of financially assisting economically constrained households after a disaster.  相似文献   

10.
The intensity of rural depopulation in Catalonia has diminished since the 1980s. New population growth patterns are occurring in rural areas, basically due to immigration. Although there has been a certain awareness of the magnitude of this process and its territorial distribution, little is known about the protagonists in this immigration and the impact on rural municipalities. Results are presented from a study of the immigration process in a group of rural inland municipalities close to the Costa Brava, a Mediterranean coastal region with extensive tourism. The great beauty of the landscape and the existence of housing stock that is being abandoned but remains desirable have led to a population influx from Catalonia’s large urban areas, especially Barcelona, purchasing these homes as a primary or secondary residence.This has led to rehabilitation of the housing stock, but also to higher housing prices and the resulting exodus of the young local population that cannot afford them; a potential source of conflict between the local population and the newcomers. The study is based on census data and statistical records, as well as extensive fieldwork, including interviews with local residents, newcomers and key informants.  相似文献   

11.
近年来,高填方边坡失稳给山区机场建设和运营带来了严重影响。本文以攀枝花机场12#滑坡为研究实例,阐述了高填方边坡的滑动失稳机制及其稳定性支护措施的有效性。论文首先介绍了滑坡的地质环境、滑坡基本特征及边坡的预加固方案。在对滑坡的形成条件及其影响因素分析的基础上,结合数值模拟,揭示了12#滑坡的形成机制及其变形发展过程。研究表明,导致滑坡的主导因素包括:填方边坡底部的软弱泥岩层、边坡内部丰富的地下水、边坡加固桩不合理的布置以及强降雨。12#滑坡的形成机制可以概括为:推移式蠕滑-累进性剪断-溃滑与超覆。  相似文献   

12.
Airports, mobility and the calculative architecture of affective control   总被引:2,自引:0,他引:2  
Peter Adey 《Geoforum》2008,39(1):438-451
Drawing on work surrounding the theorisation of concepts such as mobility, affect and emotion, the paper argues that their control is now being intertwined in places like airports which are employing a number of techniques that engineer affects. Airport affect is enacted, in one way, by planning and designing the situational affective context one inhabits - throwing up structures of ethological possibility that shape capacities for the corporeal body to move and be moved. It is shown that the engineering of airport affect is premised upon a wider discursive framework of calculation and indeterminacy, and that selective techniques summon a number of different modalities of control. The paper concludes with a series of implications for the understanding of power, and the study of mobility, emotion and affect.  相似文献   

13.
阿里机场位于西藏阿里地区,是我国海拔第二高机场,处于高原寒带季风干旱气候区,年平均气温在0℃以下。由于机场场区地下水埋深浅,且含有一定盐分,形成了盐渍化季节性冻土。盐渍化季节性冻土工程地质性质独特,在我国机场建设历史上尚属首次发现,在设计和施工中没有类似工程经验可以借鉴。本文通过对盐渍化季节性冻土工程地质特性的研究,提出了有针对性的技术处理方案,并运用到工程建设中。机场经两年多的运行和相关监测验证,该技术方法成功解决了机场场道地基盐渍化季节性冻土问题,从而为我国类似高原机场建设积累了宝贵经验。  相似文献   

14.
This study examined the water and chemical cycles of a small forested head catchment. Application of Cl? mass balance lead to the identification of a groundwater baseflow located into the active zone of the crystalline aquifer, below the weir. These findings indicate that groundwater contributes to a large part of chemical outputs at the catchment scale. This study shows that groundwater should not be ignored in most small watershed studies because this flow path and associated solutes are strongly significant for chemical balance assessment.  相似文献   

15.
This paper reviews housing policy development in Lithuania in the light of previous literature which reinterprets Esping-Andersen’s work on welfare regimes and adopts it to study housing policy. It seeks to highlight the major features of the Lithuanian housing policy. The findings of this paper reveal that the Lithuanian housing regime exhibits many features which are common under the liberal one. Most significant of these are low de-commodification for those who have to buy or rent a home for the market price, increasing stratification based on income and the dominant position of the market in housing production, allocation and price determination. However, a detailed examination of the Lithuanian housing policy reveals that the housing policy system, despite having many features similar to the liberal one, has been operating in different social and economic settings as a result of unique historical experience of the communist housing policy (massive production of low quality apartment blocks during the communist era, which currently need substantial renovation) and consequently drastic changes in the housing field since 1990s (massive privatization of the housing stock and decentralization of the housing management system). The Lithuanian housing policy regime could be characterized as a regime with the higher owner-occupation compared to other welfare state regimes, but the lower economic power of the owners to take care of their property maintenance, repair and renovation.  相似文献   

16.
Despite a growing literature on post-disaster recovery, our understanding of how housing recovery is measured remains limited. This paper is a step in filling the gap in the literature by presenting an overview of how recovery organizations measured post-disaster permanent housing recovery in Gölcük, Turkey, following the August 17, 1999 earthquake. Based on in-depth interviews, focus groups, participant observation, and review of secondary sources, the paper highlights the limitations of measuring housing recovery as the number of permanent housing units built in a timely manner. It suggests that recovery organizations need to measure post-disaster housing recovery by developing context-specific, process- and outcome-oriented measures. In the case of Gölcük, process-oriented measures could have been related to the land appropriation, public participation processes, and inter-organizational collaboration while outcome-oriented measures could have been related to the level of satisfaction with homes built and equity among the housing beneficiaries.  相似文献   

17.
This paper offers an exploratory examination of the urban mental maps and housing estate preferences of council tenants. The study area is the council housing market of the city of Birmingham. The data are based on an interview survey of transfer applicants on six Birmingham ‘study estates’ which provide contrasts in terms of age and location. The findings generally offer support for J.S. Adams' sectoral mental maps hypothesis, although important differences are disclosed among the familiarity spaces of tenant groups defined on the basis of the study estates. The results are also suggestive of a general sharpening of preferences for council estates located inside the home sector, with tenants expressing a net preference for older suburban housing areas. Conversely, the least popular estates are located in the inner/middle rings of the city and characterized by relatively large concentrations of New Commonwealth immigrants.  相似文献   

18.
一种人工影响天气微型无人驾驶飞机及初步试验   总被引:5,自引:0,他引:5  
人工影响天气微型无人驾驶飞机用于复杂天气下人影作业,是可控和可回收探测器和播撒器。人工影响天气微型无人驾驶飞机系统由微型飞机、任务载荷(机载撒播装置和探测装置)及地面监视控制三部分构成。飞行前通过计算机给飞机上的机载控制系统设置航线,遥控起飞后可由机载控制系统控制,飞机按照预定航线进行自主飞行。在需要修改飞行方向时,也可通过遥控终端发出指令。在到达作业高度后,通过遥控终端发出指令,飞机开始播撒作业。在整个飞行过程中飞机不断探测大气温压湿和风,连续将探测资料和飞行数据发送给地面监视终端。通过试验验证了人工影响天气微型无人驾驶飞机飞行性能和探测能力:能够在携带1 kg播撒剂的情况下,飞达6 km的高度,作业半径20 km;能在雨天进行播撒作业和探测;飞机采用手掷起飞,对起飞的场地几乎没有要求;采用降落伞降落,可选择草地、农田降落。初步分析了对对流降水和雷电天气的适应能力。  相似文献   

19.
山区机场高填方地基工后沉降变形简化算法   总被引:3,自引:0,他引:3  
我国西部山区机场建设的迅猛发展导致高填方地基日益增多。填方体量大、高度高,且存在软弱原地基是此类填方地基的主要特点,这也增加了预测其工后沉降变形的难度。针对山区机场高填方地基的构成特点,将其工后沉降变形的计算分为软弱原地基和上部粗粒填料填方体两部分进行考虑。在分析比较已有简化算法的基础上,对软弱原地基的沉降变形提出了可以考虑施工加载过程的简化计算方法,并应用此法对实际工程进行了计算,所得结果与现场实测值吻合相对较好;通过对室内试验数据进行分析,发现双曲线模型亦能较好的预测粗粒料的蠕变变形,进而在此基础上提出了计算粗粒料填方体长期蠕变变形的简化算法。  相似文献   

20.
Dr. David King 《GeoJournal》1988,16(2):201-209
Most towns in Papua New Guinea are small and the hierarchy comprises many isolated outstations and small towns. As a response to changes in economic policy the largest towns are growing rapidly at the expense of the small service centres. Changes in the population structure of these large towns have resulted in high rates of natural increase, while rural urban migration is steadily bringing in newcomers, to face urban unemployment and a lack of adequate housing. A secondary urban problem arises from the colonial legacy of urban zoning, which exacerbates the housing shortage and has created artifical socioeconomic residential areas. Although social differences are relatively small, the policy of economic growth will increase the gap between rich and poor, while urban unemployment and lack of housing have reached a crisis level in the rapidly growing big towns.  相似文献   

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