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291.
《Geoforum》2015
Over the last decade, fire governance practices in the British Fire and Rescue Service (FRS) have undergone fundamental transformation. Rather than just being responded to as and when they occur, the FRS have adopted a range of anticipatory governing strategies to govern fires in anticipation of their occurence. This turn towards anticipatory governance has been facilitated in no small part by the digital infrastructure now embedded in the FRS. Composed of data, hardware, software, fibre-optic cables along with human analysts and organisational processes, this infrastructure operates to make risk projections on fire which shape and condition strategic decision making. This paper explores the operation of this digital infrastructure through the notion of interface. Drawing on empirical material relating to processes of data sourcing and risk calculation, interfaces account for the sites, moments and experiences in which human and non-human agents relate to one another in making fire risk projections. Showing relations to exist spatially, temporally and sensually, I argue that interfaces are crucial to the operation of an anticipatory security apparatus which relies on digital devices. 相似文献
292.
293.
杭州市典型雨转雪天气成因及预报模型 总被引:1,自引:0,他引:1
利用2008—2018年的NCEP(1°×1°)再分析资料、常规气象观测资料和降雪加密观测资料,选出杭州地区10次典型的雨转雪天气过程,从大尺度环流背景和动力、水汽以及热力因子等物理量场结构方面展开研究,最终得出杭州冬季典型雨转雪天气的预报模型:①大尺度环流配置需满足能为雨转雪天气的形成提供有利的水汽、动力抬升以及中低层上暖下冷的逆温或等温层结条件;②水汽和动力因子等物理量须满足产生纯雪的特定条件;③杭州温度层结须为T_(2m)≤1.5℃、T_(925)≤-4.0℃、T_(850)≤0℃、T_(700)≤-1.0℃和T_(500)≤-10.0℃。此外,进一步补充了杭州可能产生大雪甚至暴雪量级降雪的特定条件。最终选取2019年初的2次典型降水过程进行预报回报检验。 相似文献
294.
In this study, two modes of the Silk Road pattern were investigated using NCEP2 reanalysis data and the simulation produced by Spectral Atmospheric Circulation Model of IAP LASG, Version 2 (SAMIL2.0) that was forced by SST observation data. The horizontal distribution of both modes were reasonably reproduced by the simulation, with a pattern correlation coefficient of 0.63 for the first mode and 0.62 for the second mode. The wave train was maintained by barotropic energy conversion (denoted as CK) and baroclinic energy conversion (denoted as CP) from the mean flow. The distribution of CK was dominated by its meridional component (CK y ) in both modes. When integrated spatially, CK y was more efficient than its zonal component (CK x ) in the first mode but less in the second mode. The distribution and efficiency of CK were not captured well by SAMIL2.0. However, the model performed reasonably well at reproducing the distribution and efficiency of CP in both modes. Because CP is more efficient than CK, the spatial patterns of the Silk Road pattern were well reproduced. Interestingly, the temporal phase of the second mode was well captured by a single-member simulation. However, further analysis of other ensemble runs demonstrated that the successful reproduction of the temporal phase was a result of internal variability rather than a signal of SST forcing. The analysis shows that the observed temporal variations of both CP and CK were poorly reproduced, leading to the low accuracy of the temporal phase of the Silk Road pattern in the simulation. 相似文献
295.
The High Energy Stereoscopic System (H.E.S.S.) is a system of Imaging Atmospheric Cherenkov Telescopes (IACTs) located in the Khomas Highland in Namibia. It measures cosmic gamma rays of very high energies (VHE; >100 GeV) using the Earth’s atmosphere as a calorimeter. The H.E.S.S. Array entered Phase II in September 2012 with the inauguration of a fifth telescope that is larger and more complex than the other four. This paper will give an overview of the current H.E.S.S. central data acquisition (DAQ) system with particular emphasis on the upgrades made to integrate the fifth telescope into the array. At first, the various requirements for the central DAQ are discussed then the general design principles employed to fulfil these requirements are described. Finally, the performance, stability and reliability of the H.E.S.S. central DAQ are presented. One of the major accomplishments is that less than 0.8% of observation time has been lost due to central DAQ problems since 2009. 相似文献
296.
Accelerometer measurements made by Spirit and Opportunity during their entries through the martian atmosphere are reported. Vertical profiles of atmospheric density, pressure, and temperature with sub-km vertical resolution were obtained using these data between 10 and 100 km. Spirit's temperature profile is ∼10 K warmer than Opportunity's between 20 and 80 km. Unlike all other martian entry profiles, Spirit's temperature profile does not contain any large amplitude, long wavelength oscillations and is nearly isothermal below 30 km. Opportunity's temperature profile contains a strong inversion between 8 and 12 km. A moderate dust storm, which occurred on Mars shortly before these two atmospheric entries, may account for some of the differences between the two profiles. The poorly known angle of attack and unknown wind velocity may cause the temperature profiles to contain errors of tens of Kelvin at 10 km, but these errors would be an order of magnitude smaller above 30 km. On broad scales, the two profiles are consistent with Mars Global Surveyor Thermal Emission Spectrometer (TES) pressure/temperature profiles. Differences exist on smaller scales, particularly associated with the near-isothermal portion of Spirit's profile and the temperature inversion in Opportunity's profile. 相似文献
297.
《The Professional geographer》1988,40(1):106-116
software reviews are in this article BMDP/PC CONCEPTS COMPUTERIZED ATLAS EVALUATION OF ALTERNATE PROPOSALS (EAP) EXTRA: EXPRESS TRANSIT ANALYSIS MATC CAD MOTORS TRANSPORTATION PACKAGE PCMAP: Thematic Mapping Software for the IBM Personal Computer, Version 2.3 PLACE TRANPLAN . US-ATLAS 相似文献
298.
《The Professional geographer》1982,34(4):458-490
Books reviewed in this article: Aerial Photography and Remote Sensing. Terrain Analysis and Remote Sensing . JOHN R. G. TOWNSHEND , ed. Environmental Data Use in Computer-assisted Data Handling Systems: The Results of a Survey of Applications in the Pacific Northwest States . KENNETH E. GORDON . Applied Land Use: A Spatial Approach . JOHN F. LOUNSBURY , LAWRENCE M. SOMMERS , AND EDWARD A. FERNALD , eds. The Second Battle of New Orleans: A History of the Vieux Carre Riverfront-Expressway Controversy . RICHARD O. BAUMBACH , JR. AND WILLIAM E. BORAH . Cultural Environmental Archaeology . MYRA SHACKLEY . The Immoral landscape: Female Prostitution in Western Societies . RICHARD SYMANSKI . life Among the Poor in Cairo . UNNI WIKAN , translated by Ann Henning. Women, Work and Property in Northwest India . URSULA SHARMA . The Domestication of Women: Discrimination in Developing Societies . BARBARA ROGERS Economic Optimization in Locational and Transport Analysis . A. G. WILSON , J. D. COELHO , S. M. MACGILL , H. C. W. L. WILLIAMS . New Tools for Economic Development: The Enterprise Zone, Development Bank, and RFC . GEORGE STERNLIEB AND DAVID LISTOKIN , eds. Regional Wage Inflation . R. L. MARTIN , ed. Finding A Place For Energy-Siting Coal Conversion Facilities . FRANK J. CALZONETTI WITH MARK S. ECKERT . Environmental Management, Resources, and Systems Environmentalism. Second Edition . T. O'RIORDAN . Countryside Conservation . BRYN GREEN . Medical Spatial Diffusion: An Historical Geography of Epidemics in an Island Community . A. D. CLIFF , P. HAGGETT , J. K. ORD , AND G. R. VERSEY . Philosophy and Geographic Thought Order and Skepticism: Human Geography and the Dialectic of Science . RICHARD SZYMANSKI AND JOHN A. AGNEW . Measurement of Subjective Phenomena . D. F. JOHNSTON , ed. Conceptions of Space in Social Thought: A Geographic Perspective . ROBERT DAVID SACK . The Association of American Geographers: The First Seventy-five Years: 1904-1979 . PRESTON E. JAMES AND GEOFFREY J. MARTIN . The Life and Thought of Isaiah Bowman . GEOFFREY J. MARTIN . Physical River Basin Planning: Theory and Practice . SURANJIT K. SAHA AND CHRISTOPHER J. BARROW , eds. Soils and landforms: An Integration of Ceomorphology and Pedology . A. I. GERRARD Climatic Change and Society. Consequences of Increasing Atmospheric Carbon Dioxide . WILLIAM W. KELLOGG AND ROBERT SCHWARE . Political Political Redistrictings and Geographic Theory . RICHARD L. MORRILL . Population Studies in Spanish American Population History: Dell Plain Latin American Studies NO. 8 . DAVID J. ROBINSON , ed. Population Redistribution in the Midwest . CURTIS C. ROSEMAN , ANDREW J. SOFRANKO , AND JAMES D. WILLIAMS , eds. Geographical Perspectives on the Elderly . A. M. WARNES , ed. Regional Perspective On the American South . MERLE BLACK AND JOHN SHELTON REED , eds. The Prairies and Plains: Prospects for the 80s . JOHN R. ROGGE , ed. Rural Rural Settlement in an Urban World . MICHAEL BUNCE . Social Accident at Three Mile Island: The Human Dimensions . DAVID L. SILLS , C. P. WOLF , AND VIVIEN B. SHELANSKI , eds. The American Small Town: Twentieth-Century Place Images . JOHN JAKLE . Urban A House of My Own . SUSAN LOBO . The City: Patterns and Processes in the Urban Ecosystem . CHRISTOPHER H. EXLINE , GARY L. PETERS , AND ROBERT P. LARKIN . Movement in Cities . P. W. DANIELS AND A. M. WARNES . Urbanization and Urban Planning in Capitalist Society . MICHAEL DEAR AND ALLEN J. SCOT , eds. 相似文献
299.
300.
Methodological Development of the Conditional Sampling Method. Part II: Quality Control Criteria of Relaxed Eddy Accumulation Flux Measurements 总被引:1,自引:1,他引:0
A.?K.?Fotiadi F.?Lohou A.?Druilhet D.?Ser?aEmail author F.?Said P.?Laville A.?Brut 《Boundary-Layer Meteorology》2005,117(3):577-603
Determination of biosphere–atmosphere exchanges requires accurate quantification of the turbulent fluxes of energy and of
a wide variety of trace gases. Relaxed Eddy Accumulation (REA) is a method that has received increasing attention in recent
years, because it does not require any rapid sensor for the scalar measurements as the Eddy Correlation method (EC) does.
As in all micrometeorological studies, REA measurements in the atmospheric surface layer are valid under some restrictive
conditions so as to be representative of a specific ecosystem. These conditions are the homogeneity of the underlying surface,
stationary and horizontally homogeneous turbulence. For most experiments these conditions are not fully satisfied. Data uncertainties
can also be related to not fulfilling the method principles or to the technical characteristics of the REA system itself.
In order to assess REA measurement quality, a methodological approach of data analysis is developed in this study. This methodological
analysis is based on the establishment of criteria for data quality control. A set of them, deduced from the mean and turbulent
flow, are called ‘Dynamic criteria’ and are designated to control the stationarity and homogeneity of the w function and the validation of Taylor’s hypothesis. A second set (‘REA operational criteria’) is designed to check the sampling
process and, more precisely, the homogeneity of the negative and positive selection process throughout the sampling period.
A third set of criteria (‘Chemical scalar criteria’) concerns the scalar measurements. Results of the criteria application
to data measured at two different experimental sites are also presented. Cut-off limits of criteria are defined based on their
statistical distribution and shown to be specific for each site. Strictness of each criterion, defined by the percentage of
flagged samples, is analysed in conjunction with the meteorological conditions and atmospheric stability. It is found that
flagged samples mainly correspond to neutral and stable nocturnal conditions. During daytime, nearly free convection conditions
can also yield poor quality data. 相似文献