中国生产性服务业发展与空间分布   总被引：1，自引：0，他引：1  

杨帆  叶嘉安 《热带地理》2013,33(2):178-186

从分行业的角度探讨了中国生产性服务业的发展特征及其在城市体系中的空间分布。研究表明,中国生产性服务业的发展水平还处在初级阶段,虽然高级别生产性服务业增长较快,但是所占比重较小。空间分布上,生产性服务业倾向于集中在特大城市。由于其在经济发展中发挥重要的作用,这种分布特征重组了城市等级结构和城市之间的经济联系。随着中国经济的持续增长和政府的政策支持,对生产性服务业的需求将大大增加。全球化背景下,发展生产性服务业也成为重要的城市发展战略。但是,生产性服务业不均衡的分布格局决定了大城市和特大城市在新一轮的城市发展中具有更大的竞争力。因此,中小城市在发展生产性服务业时必须进行深入的分析,以免造成用地和资金的浪费。  相似文献   

A new deal for lone parents? Training lone parents for work in West London     

Fiona Smith  John Barker  Emma Wainwright  Elodie Marandet  Sue Buckingham 《Area》2008,40(2):237-244

In this paper we explore the impacts of the training programmes offered to lone mothers with young children on the Government's 'New Deal for Lone Parents' in one local labour market: West London. Our research suggests that regulatory workfare policies are (re)producing and reinforcing gendered inequalities in the labour market by encouraging lone mothers to undertake training in feminised occupational areas such as childcare. We will argue that in a local economy such as West London where more childcare workers are desperately needed to enable other more highly skilled workers to take up employment opportunities, such training programmes may be doing little more than exacerbating the already gendered and class-based polarisation of the labour market – embedding low-skilled, poorly qualified lone mothers into low-paid jobs.  相似文献   

Commodifying the countryside: the impact of out-of-school care on rural landscapes of children's play   总被引：1，自引：0，他引：1  

Fiona Smith  & John Barker 《Area》2001,33(2):169-176

The growing interest in rural geography has highlighted that symbolic representations of the 'rural idyll' are often contradictory to the lived experiences of many rural children. Increasingly, children's spatial mobility is restricted due to adult concerns over children's use of public space, and the continuing privatization of rural space. Whilst children are prevented from using the countryside as a resource, there is also a lack of provision and spaces dedicated to children's play. One exception to this is the development of out-of-school care schemes. The rapidly expandingout-of-school care service is providing rural children with a significant, well-resourced place for children to play. This paperexamines children's experiences of playing in the countryside, and discusses the impact of the developing out-of-school care service on the daily lives of children who experience the service. The paper also considers the impact of commodifying children's play on the ability of all children to access a local play service.  相似文献   

Extracts of impact breccia samples from Sudbury, Gardnos, and Ries impact craters and the effects of aggregation on C₆₀ detection     

Jamie E. Elsila  Fiona L. Plows  Richard N. Zare 《Geochimica et cosmochimica acta》2005,69(11):2891-2899

Fullerenes have been detected in carbonaceous chondrite meteorites and in breccia samples from meteorite impact craters, but questions have been raised about contradictory results from similar samples and the sensitivities and accuracies of different analytical methods. We analyzed samples from three impact craters and detected C₆₀ in samples from several locations; we also observed differences in the detection capabilities of various analytical techniques used in the search for fullerenes. The presence of C₆₀ in rocks from the Onaping Formation of the Sudbury impact crater was confirmed. Low levels of C₆₀ were also detected for the first time in samples from the Gardnos (Norway) and Ries (Germany) impact structures.We detected C₆₀ in these samples using surface-enhanced laser desorption/ ionization (SELDI), but the related technique of microprobe laser-desorption, laser-ionization mass spectrometry (μL²MS) did not observe C₆₀ above detection limits. We attribute the absence of μL²MS signal to aggregate formation caused by phthalic acid esters, which appear to easily contaminate samples either during storage or demineralization in plastic containers. The μL²MS technique is incapable of detecting aggregated C₆₀, but aggregation does not suppress detection in SELDI. Phthalate-induced aggregation did, however, enhance SELDI detection of C₆₀ in some cases, and we suggest that this enhancement may help explain previously reported differences in C₆₀ detection from natural samples between laser desorption mass spectrometry (LDMS, a technique analogous to SELDI that has detected fullerenes in meteorite and impact breccia samples) and high-pressure liquid chromatography (HPLC). This work highlights the effects of phthalates and other indigenous compounds or contaminants on certain mass spectrometric techniques and lends support to the idea that several complementary analytical methods should be employed to investigate complex natural samples.  相似文献   

4D signal enhancement using singular-value decomposition: application to mapping oil–water contact movement across the Nelson Field     

Fiona J.L. Reid  Alexandre Bertrand †  Alan T. McInally ‡  Colin MacBeth 《Geophysical Prospecting》2005,53(2):253-263

A new method for time‐lapse signal separation and enhancement using singular‐value decomposition is presented. Singular‐value decomposition is used to separate a 4D signal into its constituent parts: common geology, time‐lapse response and noise. Synthetic tests which demonstrate the advantages of the singular‐value decomposition technique over traditional differencing methods are also presented. This signal separation and enhancement technique is used to map out both the original and moved oil–water contacts across the Nelson Field. The singular‐value decomposition technique allows the oil–water contact to be mapped across regions which would have been missed using traditional differencing methods. In particular, areas toward the edges of the field are highlighted by the technique. The oil–water contact is observed to move upwards across the field, with the largest movements being associated, as anticipated, with natural production. The results obtained are broadly consistent with those predicted by the reservoir simulator model. Singular‐value decomposition is demonstrated to be a useful tool for enhancing the time‐lapse signal and for gaining confidence in areas where traditional differencing fails.  相似文献   

The liminality of training spaces: Places of private/public transitions     

Susan Buckingham  Elodie Marandet  Fiona Smith  Emma Wainwright  Marilyn Diosi 《Geoforum》2006,37(6):895-905

This paper draws upon research, conducted for the London West Learning and Skills Council, on the training experiences of women with dependent children. One of the striking revelations of the research, we suggest, is the way in which training spaces are used and perceived by women, which are often at odds with government intentions. To help make sense of women’s use of, and motivation for, training we utilise the concept of ‘liminality’ and the private/public imbrication to explain the ways in which women use, or are discouraged from using, training spaces. Further, how the varied and multiple uses women in our research have put training to in their own lives has encouraged us to rethink the relationship between the private and the public more generally. In the light of this, we suggest that training and the places in which training take place, have been neglected processes and spaces within feminist geography and might usefully be explored further to add to an extensive literature on women’s caring and domestic roles and their role in the paid workplace.  相似文献   

Constructing Risk: multi-scale change,livelihoods and vulnerability in the Mekong Delta,Vietnam     

Fiona Miller 《The Australian geographer》2014,45(3):309-324

ABSTRACT

Change has been at the heart of the livelihoods concept since its inception, allowing for a clear focus on how people perceive, respond to and experience risk. The ardent focus on ‘the local’ within livelihoods work, both in research and programmatic terms, has to some extent overshadowed attention on the role of wider-scale political economic and environmental processes in generating change and determining responses to change. Livelihoods in the Mekong Delta have never been ‘local’, having long been historically embedded in international, regional and national economic, political and environmental transformations. Drivers of change at these wider scales have intensified, complicating local responses to change, whether through economic, social or political means. A more nuanced appreciation of how scaled relations can be supported is required to better anticipate and respond to the political ecology of risk.  相似文献   

Ejection behavior characteristics in experimental cratering in sandstone targets     

Frank SOMMER  Fiona REISER  Anja DUFRESNE  Michael H. POELCHAU  Tobias HOERTH  Alex DEUTSCH  Thomas KENKMANN  Klaus THOMA 《Meteoritics & planetary science》2013,48(1):33-49

Abstract– Within the frame of the MEMIN research unit (Multidisciplinary Experimental and Numerical Impact Research Network), impact experiments on sandstone targets were carried out to systematically study the influence of projectile mass, velocity, and target water saturation on the cratering and ejection processes. The projectiles were accelerated with two‐stage light‐gas guns (Ernst‐Mach‐Institute) onto fine‐grained targets (Seeberger sandstone) with about 23% porosity. Collection of the ejecta on custom‐designed catchers allowed determination of particle shape, size distribution, ejection angle, and microstructures. Mapping of the ejecta imprints on the catcher surface enabled linking of the different patterns to ejection stages observed on high‐speed videos. The increase in projectile mass from 0.067 to 7.1 g correlates with an increase in the total ejected mass; ejecta angles, however, are similar in range for all experiments. The increase in projectile velocity from 2.5 to 5.1 km s^?1 correlates with a total ejecta mass increase as well as in an increase in comminution efficiency, and a widening of the ejecta cone. A higher degree of water saturation of the target yields an increase in total ejecta mass up to 400% with respect to dry targets, higher ejecta velocity, and a steeper cone. These data, in turn, suggest that the reduced impedance contrast between the quartz grains of the target and the pores plays a primary role in the ejecta mass increase, while vaporization of water determines the ejecta behavior concerning ejecta velocity and particle distribution.  相似文献   

Geochemistry of meteoric diagenesis in carbonate islands of the northern Bahamas: 2. Geochemical modelling and budgeting of diagenesis     

Fiona F. Whitaker  Peter L. Smart 《水文研究》2007,21(7):967-982

Geochemical characterization and numerical modelling of surface water and ground water, combined with hydrological observations, provide quantitative estimates of meteoric diagenesis in Pleistocene carbonates of the northern Bahamas. Meteoric waters equilibrate with aragonite, but water‐ rather than mineral‐controlled reactions dominate. Dissolutional lowering of the undifferentiated bedrock surface is an order of magnitude slower than that within soil‐filled topographic hollows, generating small‐scale relief at a rate of 65–140 mm ka^?1 and a distinctive pocketed topography. Oxidation of organic matter within the subsoil and vadose zones generates an average P of 4·0 × 10^?3 atm, which drives dissolution during vadose percolation and/or at the water table. However, these dissolution processes together account for <60% of the average rock‐derived calcium in groundwaters pumped from the freshwater lens. The additional calcium may derive from oxidation of organic carbon within the lens, accounting for the high P of the lens waters. Mixing between meteoric waters of differing chemistry is diagenetically insignificant, but evapotranspiration from the shallow water table is an important drive for subsurface cementation. Porosity generation in the shallow vadose zone averages 1·6–3·2% ka^?1. Phreatic meteoric diagenesis is focused near the water table, where dissolution generates porosity at 1·4–2·8% ka^?1. Maximum dissolution rates, however, are similar to those of evaporation‐driven precipitation, which occludes porosity of 4·0 ± 0·6% ka^?1. This drives porosity inversion, from primary interparticle to secondary mouldic, vug and channel porosity. In the deeper freshwater lens, oxidation of residual organic carbon and reoxidation of reduced sulphur species from deeper anaerobic oxidation of organic carbon may generate porosity up to 0·06% ka^?1. Meteoric diagenesis relies critically on hydrological routing and vadose thickness (controlled by sea level), as well as the geochemical processes active. A thin vadose zone permits direct evaporation from the water table and drives precipitation of meteoric phreatic cements even where mineral stabilization is complete. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

‘Body training’: Investigating the embodied training choices of/for mothers in West London     

Emma Wainwright  Susan Buckingham  Elodie Marandet  Fiona Smith 《Geoforum》2010,41(3):489-497

Framed by the UK Government’s efforts to combat social exclusion by encouraging a shift from welfare to work through (re)training, this paper explores the types of training courses being offered to and taken by women with young children in West London. Drawing upon qualitative research, the paper explores the actual and desired uptake of ‘body training’ courses among mothers, linked, in part, to the current ‘body work’ skills gap in the local economy. The encouragement given to women and the interest they have in engaging in ‘body training’ is, we suggest, linked to the discursive construction and performance of a highly feminised and, often, maternal identity, which emphasises women’s caring role and the caring self. By probing the body/training nexus through the motivations and choices of mothers in West London the paper raises questions about gender identity and stereotyping in relation to training-for-work policies and the role of training in (re)inforcing the woman-body coupling within Western dualistic thought.  相似文献