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61.
Intensive suburbanization, especially in postsocialist countries, and a deficiency of fully public spaces result in an increasingly complex mixture of different types of spaces of public functions. Where there is a deficiency of completely public spaces, their role can be enhanced by those places available to the public for a specified period of time and under certain circumstances. Such places are provided and maintained not only by the public but also by the private sector. This article explores the diversity of places of public character and looks for criteria that organize this diversity. It introduces a new typology that corresponds mainly to the suburbs and combines five criteria of categorization: intended users, time limits as to access, prevailing form of control, intended functions, and visual characteristics. The typology draws attention to the role of spaces not intended for all the public but for selected groups and that of spaces with time-limited access. Such semipublic places are consistent with the lifestyle of suburbanites and therefore play an increasingly important role in suburban social life. 相似文献
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James C. Hower Maria Mastalerz Agnieszka Drobniak Jeffrey C. Quick Cortland F. Eble Matthew J. Zimmerer 《International Journal of Coal Geology》2005,63(3-4):205-227
With pending regulation of mercury emissions in United States power plants, its control at every step of the combustion process is important. An understanding of the amount of mercury in coal at the mine is the first step in this process. The Springfield coal (Middle Pennsylvanian) is one of the most important coal resources in the Illinois Basin. In Indiana and western Kentucky, Hg contents range from 0.02 to 0.55 ppm. The variation within small areas is comparable to the variation on a basin basis. Considerable variation also exists within the coal column, ranging from 0.04 to 0.224 ppm at one Kentucky site. Larger variations likely exist, since that site does not represent the highest whole-seam Hg nor was the collection of samples done with optimization of trace element variations in mind. Estimates of Hg capture by currently installed pollution control equipment range from 9–53% capture by cold-side electrostatic precipitators (ESP) and 47–81% Hg capture for ESP + flue-gas desulfurization (FGD). The high Cl content of many Illinois basin coals and the installation of Selective Catalytic Reduction of NOx enhances the oxidation of Hg species, improving the ability of ESPs and FGDs to capture Hg. 相似文献
63.
Krystyna Szeroczyńska Andrzej Tatur Jan Weckström Michał Gąsiorowski Agnieszka M. Noryśkiewicz Elwira Sienkiewicz 《Journal of Paleolimnology》2007,38(1):25-47
A 2.5-m-long sediment core was retrieved from Lake Somaslampi, a small lake located in a kame field on the north slope of
the Scandes Mountains in Finnish Lapland. Holocene environmental changes were inferred from the lithological, geochemical,
pollen, diatom and Cladocera records stored in the lake sediment. The chronology was based on six radiocarbon AMS dates supported
by a palynological control chronology. The sediment profile consists of a glacial sedimentary sequence truncated by a lacustrine
one. A hiatus, tentatively correlated with climate cooling and advances of glaciers during the 8.2 ka yrs BP “Finse cooling
Event”, occurs between these sequences. The glacial sequence was composed of fluvioglacial clastics, smoothly changing into
glacio-lacustrine diatomaceous ooze deposited in a meromictic proglacial lake that covered the kame field. The meromixis was
probably caused by the greater depth of the lake, the extended ice-cover, and the microbial mats covering large areas of the
lake bottom. A distinct change in the biota of the glacio-lacustrine sediments indicates higher trophic conditions than during
deposition of the fluvioglacial clastics. The late-Pleistocene vegetation was characterised by subarctic birch tundra vegetation
(Betula–Salix–Ericaceae) with low biodiversity gradually changing to Betula–Pinus dominance in the early Holocene. The lake was deep and had a diatom inferred pH ~ 7 indicated also by the dominance of planktonic
Cladocera.
The base of the lacustrine sediment sequence (6,650–6,300 cal. BP) consisted of loess-rich sediment indicating an increase
in eolian activity. This is also supported by the pollen record, which is dominated by more long-distant taxa such as Alnus and Pinus, and by the increased C/N ratio of the sediment. After the initial meromictic phase of the lake, an abrupt lowering of the
water level occurred. Lake Somaslampi was isolated from the larger Pre-Lake Somas basin and became holomictic, shallow, much
warmer and more productive, until the deterioration of climate around 3,000 yr BP and the increased input of clastics from
the tundra soils. The vegetation followed the general climatic trend by gradually changing from the dominance of Betula and Pinus to the dominance of more tundra-related vegetation like Poaceae and Cyperaceae. However, the higher frequencies of planktonic
Cladocera and centric diatoms in the most recent sediments indicates higher trophic conditions, increased turbulence and a
prolonged ice-free period, which can possibly be linked to the recent climate warming especially in areas of higher altitude
and latitude. 相似文献
64.
Agnieszka Drobniak Maria Mastalerz John Rupp Nathan Eaton 《International Journal of Coal Geology》2004,57(3-4):265-282
The Seelyville Coal Member of the Linton Formation in Indiana potentially contains 0.03 trillion m3 (1.1 TCF) of coalbed gas. The gas content determined by canister desorption technique ranges from 0.5 to 5.7 cm3/g on dry ash free basis (15.4 to 182.2 scf/ton). The controls on gas content distribution are complex, and cannot be explained by the coal rank alone. Ash content and the lithology of the overlying strata, among other factors, may influence this distribution. 相似文献
65.
Agnieszka Zwirowicz-Rutkowska 《Earth Science Informatics》2017,10(3):369-382
There is a demand for evaluation of spatial data infrastructures (SDIs), to justify and monitor the relations between investments in SDI initiatives and the results obtained. It is also essential to pay particular attention to identifying user communities, and eliciting their assessment of effects deriving from an SDI. The paper introduces a concept of a multi-criteria method which allows to assess effectiveness of the SDI from the user perspective. The application of the proposed method in the Polish Spatial Data Infrastructure (PSDI) and its main access point to spatial data and services called ‘Geoportal 2’ as well as two groups of the national geoportal”s users (spatial planners and land surveyors) presents its potential. The total scores for the Geoportal 2 indicated the investment has potential and is quite effective, although some components of the PSDI (e.g. main access point, datasets, network services, software, hardware, procedures) may need improvements and additional analyses in the future. The contribution of this paper is the multi-criteria method which enables the analysis of outcomes, benefits (impacts) and business value of using SDI business project’s artifacts (outputs) considering the following dimensions: information and support provided, use process, user organizational performance, strategic alignment and business impact on user enterprise. 相似文献
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The occurrence and distribution of freshwater snails in a heavily industrialised region of Poland (Upper Silesia) 总被引:1,自引:0,他引:1
Anthropogenic water bodies namely fish ponds, clay pits, sand pits, dam reservoirs or mining subsidence pools are the characteristic feature of Upper Silesian landscape. In the study, the gastropod communities occurring in 296 anthropogenic water bodies were discussed in relation to their distribution in macroregions of Upper Silesia, role in industrialised and urbanised environment and the significance for regional biodiversity.In period 1998–2002, 31 freshwater gastropod species were found in the study area. It is noteworthy, that the anthropogenic water habitats of Upper Silesia provide a refuge for several rare and vulnerable species, among them e.g. Anisus leucostoma (Millet, 1813), Gyraulus rossmaessleri (V. Auerswald, 1852) and Hippeutis complanatus (Linnaeus, 1758). 相似文献
68.
The Schmidt hammer is a useful tool applied by geomorphologists to measure rock strength in field conditions. The essence of field application is to obtain a sufficiently large dataset of individual rebound values, which yields a meaningful numerical value of mean strength. Although there is general agreement that a certain minimum sample size is required to proceed with the statistics, the choice of size (i.e. number of individual impacts) was usually intuitive and arbitrary. In this paper we show a simple statistical method, based on the two‐sample Student's t‐test, to objectively estimate the minimum number of rebound measurements. We present the results as (1) the ‘mean’ and ‘median’ solutions, each providing a single estimate value, and (2) the empirical probability distribution of such estimates based on many field samples. Schmidt hammer data for 14 lithologies, 13–81 samples for each, with each sample consisting of 40 individual readings, have been evaluated, assuming different significance levels. The principal recommendations are: (1) the recommended minimum sample size for weak and moderately strong rock is 25; (2) a sample size of 15 is sufficient for sandstones and shales; (3) strong and coarse rocks require 30 readings at a site; (4) the minimum sample size may be reduced by one‐third if the context of research allows for higher significance level for test statistics. Interpretations based on less than 10 readings from a site should definitely be avoided. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Wind-wave variability in a shallow tidal sea—Spectral modelling combined with neural network methods
In this paper the wind-wave variability in the tidal basins of the German Wadden Sea is modelled with combined numerical and neural-network (NN) methods. First, the wave propagation and transformation in the study area are modelled with the state-of-the-art third-generation spectral wave model SWAN. The ability of SWAN to accurately reproduce the phenomena of interest in nonstationary conditions governed by highly variable winds, water levels and currents is shown by comparisons of the modelled and measured mean wave parameters at four stations. The principal component analysis of the SWAN results is then used to reveal the dominating spatial patterns in the data and to reduce their dimensionality, thus enabling an efficient and relatively straightforward NN modelling of mean wave parameters in the whole study area. It is shown that the data produced with the approach developed in this work have statistical properties (discrete probability distributions of the mean wave parameters etc.) very close to the properties of the data obtained with SWAN, thus proving that this approach can be used as a reliable tool for wind wave simulation in coastal areas, complementary to (often computationally demanding) spectral wave models. 相似文献