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1.
The article discusses the effects of changing the parking situation in the surrounding of shopping centres on consumers store
choice behaviour. To get insight into these effects a hierarchical logit model of parking lot and store choice behaviour is
estimated and validated. The research is based on before-and-after data of supermarket visitors collected in a major regional
shopping centre in a suburban area in The Netherlands.
The model is estimated using the before data. At the level of the supermarkets the estimated hierarchical logit model performs
very well. The model is less accurate at the level of parking lots but still performs satisfactory. Significant attributes
are a constant representing the characteristics of the supermarket, the distance between supermarket and parking lot, the
number of parking spaces per parking lot, the location of the parking lot vis-à-vis the origin of the consumer, and the availability
of supermarket trolley facilities at the parking lot. Validating the model by reproducing the after data yields less satisfactory
results. Especially the model does not perform very well on predicting parking lot choice.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Jean Carlos Montero-Serrano Viviane Bout-Roumazeilles Nicolas Tribovillard Thomas Sionneau Armelle Riboulleau Aloys Bory Benjamin Flower 《Quaternary Science Reviews》2009,28(27-28):3333-3347
Cored sediments from the Pigmy Basin, northern Gulf of Mexico, were analyzed in order to better constrain late deglacial and early Holocene paleoenvironmental and sedimentary changes in response to North American climate evolution. Mineralogical and geochemical proxies indicate the succession of two sedimentary regimes: dominantly detrital during the deglaciation (15–12.9 cal ka BP) whereas biogenic contribution relatively increased later on during the Younger Dryas and early Holocene (12.9 and 10 cal ka BP). Geochemical data reveal that the deglacial record mainly reflects variations of terrigenous supply via the Mississippi River rather than modifications of redox conditions in the basin. Specific variations of almost all the parameters measured in this paper are synchronous with the main deglacial meltwater episode (Meltwater Spike) described or modeled in previous marine or continental studies. During this episode, most parameters display “stair-step-like” – pattern variations highlighting three successive steps within the main meltwater flow. Variations in grain-size and clay mineral assemblage recorded in the Pigmy Basin indicate that the erosional regime was very strong on land during the first part of the Meltwater Spike, and then milder, inducing more subtle modifications in the sedimentary regime in this part of the Gulf. Specific geochemical and mineralogical signatures (notably, clay minerals and trace metal geochemistry) pinpoint a dominant origin from NW North America for detrital particles reflecting meltwater outflow from the south-western Laurentide Ice Sheet (LIS) margin during the most intense freshwater discharge. The observed decrease of the sedimentation rate from about 200 to 25 cm/ka at ca 12.9 ka evidenced a drastic decrease of erosional processes during late phase of discharge, consistently with the hypotheses of major reduction of meltwater flow. The major modification at 12.9 cal ka BP is interpreted to result from both modifications of the main Mississippi fluvial regime due to eastward and northward rerouting of meltwater flow at the onset of the Younger Dryas, and the increase of sea-surface temperature linked to insolation. Finally, slight grain-size modifications suggest that some freshwater discharges may have episodically reached the Gulf of Mexico after the Younger Dryas reflecting possible small adjustments of the postglacial hydrological regime. 相似文献
3.
Hillary Agaba Lawrence Justus Baguma Orikiriza John Francis Osoto Esegu Joseph Obua John David Kabasa Aloys Hüttermann 《洁净——土壤、空气、水》2010,38(4):328-335
The effect of super absorbent polyacrylate (SAP) hydrogel amendment to different soil types on plant available water (PAW), evapotranspiration and survival of Eucalyptus grandis, Eucalyptus citriodora, Pinus caribaea, Araucaria cunninghamii, Melia volkensii, Grevillea robusta, Azadirachta indica, Maesopsis eminii and Terminalia superba was investigated. The seedlings were potted in 3 kg size polythene bags filled with sand, loam, silt loam, sandy loam and clay soils, amended at 0 (control), 0.2 and 0.4% w/w hydrogel. The tree seedlings were allowed to grow normally with routine uniform watering in a glass house set up for a period of eight weeks, after which they were subjected to drought conditions by not watering any further. The 0.4% hydrogel amendment significantly (p < 0.05) increased the PAW by a factor of about three in sand, two fold in silt loam and one fold in sandy loam, loam and clay soils compared to the control. Similarly, the addition of either 0.2 or 0.4% hydrogel to the five soil types resulted in prolonged tree survival compared to the controls. Araucaria cunninghammi survived longest at 153 days, while Maesopsis eminii survived least (95 days) in sand amended at 0.4% after subjection to desiccation. Evapotranspiration was reduced in eight of the nine tree species grown in sandy loam, loam, silt loam and clay soils amended at 0.4% hydrogel. It is probable that soil amendment with SAP decreased the hydraulic soil conductivity that might reduce plant transpiration and soil evaporation. 相似文献
4.
Theo A. Arentze Aloys W. J. Borgers Harry J. P. Timmermans 《International journal of geographical information science》2013,27(2):219-236
Abstract. The traditional approach in DSS falls short of providing a highly interactive problem solving environment for planning. Often, cumbersome procedures are required to implement optional plans and obtain feedback information. In dynamic graphic systems, the user is able to view different linked graphic representations (e.g., spatial or statistical graphs) of statistical data and interact (e.g., selecting items) with these graphics. In this paper we describe the design of a DSS for planning facility locations, which uses principles of dynamic graphics to achieve a highly interactive problem solving environment. As in dynamic graphic systems, the user interacts with the DSS through active and linked views. However, where views in dynamic graphics are different representations of a given dataset, the views in the DSS are active data structures describing the facility system to be planned from different perspectives. The declarative and procedural forms of knowledge involved are identified by a logical analysis of planning problems. A frame-based formalism is proposed to represent the knowledge contained in the views. The main advantage of this view-based approach is that it offers the user a highly flexible and interactive environment for performing ‘what-if’ analyses. 相似文献
5.
Aloys Borgers Frank Hofman Maarten Ponjé Harry Timmermans 《Journal of Geographical Systems》2001,3(4):347-367
None of the currently developed activity-based models of transport demand explicitly models task allocation among household
members. To fill this gap, the present paper suggests to complement activity-based models of activity scheduling with a context-dependent
model of task allocation. That is, it is assumed that the allocation of tasks within households is partly based on such contextual
variables as the amount of time a member has to spend on mandatory activities and car availability. In particular, the paper
advocates a conjoint-based approach, based on an assignment task as opposed to the traditional ranking, rating or choice response
formats. By definition, an assignment task involves a combinatorial explosion of choice alternatives, implying that additional
operational decisions to estimate the context-dependent model are required. This study presents the results of various numerical
experiments, conducted to better understand the impacts of those decisions on the degree of bias in the parameter estimates
of the choice model. The results of these simulations indicate that under particular assumptions, the development and estimation
of a conjoint-based, context-dependent model of task allocation within households is feasible.
Received: March 1999 / Accepted: June 2001 相似文献
6.
Bruno Malaizé Elsa Jullien Amandine Tisserand Charlotte Skonieczny E. Francis Grousset Frédérique Eynaud Catherine Kissel Jérôme Bonnin Svenja Karstens Philippe Martinez Aloys Bory Vivianne Bout-Roumazeilles Thibaut Caley Xavier Crosta Karine Charlier Linda Rossignol José-Abel Flores Ralph Schneider 《Quaternary Research》2012,77(1):182-191
A high resolution analysis of benthic foraminifera as well as of aeolian terrigenous proxies extracted from a 37 m-long marine core located off the Mauritanian margin spanning the last ~ 1.2 Ma, documents the possible link between major continental environmental changes with a shift in the isotopic signature of deep waters around 1.0–0.9 Ma, within the so-called Mid-Pleistocene Transition (MPT) time period. The increase in the oxygen isotopic composition of deep waters, as seen through the benthic foraminifera δ18O values, is consistent with the growth of larger ice sheets known to have occurred during this transition. Deep-water mass δ13C changes, also estimated from benthic foraminifera, show a strong depletion for the same time interval. This drastic change in δ13C values is concomitant with a worldwide 0.3‰ decrease observed in the major deep oceanic waters for the MPT time period. The phase relationship between aeolian terrigeneous signal increase and this δ13C decrease in our record, as well as in other paleorecords, supports the hypothesis of a global aridification amongst others processes to explain the deep-water masses isotopic signature changes during the MPT. In any case, the isotopic shifts imply major changes in the end-member δ18O and δ13C values of deep waters. 相似文献
7.
Application of Superabsorbent Polymers for Improving the Ecological Chemistry of Degraded or Polluted Lands 总被引：3，自引：0，他引：3
About 3.5 billion ha of land, which amounts to almost 30% of the total solid land of the world, has been degraded by human activities. The ecological restoration of these lands is a major challenge for mankind since they are the only option left for increasing the amount of arable land and producing food for the ever growing worldwide population. One common feature of these degraded lands is the fact that their organic soil matter is degraded also. Rainfall therefore, changes from a blessing to a menace since it is not kept in the soil and therefore causes erosion. A solution for the restoration of these lands could be the application of superabsorbent polymers (SAPs) to these soils. These substances are like ‘artificial humus’ as they are hydrophilic and contain carboxylic groups. This enables them to bind cations and water. They have the following advantages for the restoration of degraded lands. They increase the plant available water in the soil which enables the plants to survive longer under water stress. SAP amendment to soils reduces the evapotranspiration rate of the plants. They induce a significantly higher growth rate in plants growing on SAP amended soil. They bind heavy metals and mitigate their action on plants. They mitigate the effects of salinity. The benefits of SAP amendment to soils substantially outweigh their costs. 相似文献
8.
Aloys A. Michel 《The Professional geographer》1966,18(6):381-381
9.
Lawrence J. B. Orikiriza Hillary Agaba Mnason Tweheyo Gerald Eilu John David Kabasa Aloys Hüttermann 《洁净——土壤、空气、水》2009,37(8):615-620
The classical aim of the application of super absorbent polyacrylate (SAPs) hydrogels is the prolonging of plant survival under water stress. Their effect on plant growth during non‐water stress conditions is not known. This study examined the root and shoot biomass of seedlings of nine tree species; Eucalyptus grandis, Eucalyptus citriodora, Pinus caribaea, Araucaria cunninghamii, Melia volkensii, Grevillea robusta, Azadirachta indica, Maesopsis eminii and Terminalia superba. The seedlings were potted in five soil types; sand, sandy loam, loam, silt loam and clay. These were amended at two hydrogel levels: 0.2 and 0.4% w/w and grown under controlled conditions in a green house. Root and shoot growth responses of the seedlings were determined by measuring the dry weight of the roots, stems, leaves and twigs. The addition of either 0.2 or 0.4% hydrogel to the five soil types resulted in a significant increase of the root dry weight (p < 0.001) in eight tree species compared to the controls after 8 wk of routine watering. Also, the dry weight of stems and leaves and twigs were significantly (p < 0.001) higher in the nine tree species potted in hydrogel amended soil types than in the hydrogel free controls. These results suggested that hydrogel amendment enhances the efficiency of water uptake and utilization of photosynthates of plants grown in soils which have water contents close to field capacity. 相似文献
10.
Elsa Jullien Francis Grousset Bruno Malaiz Josette Duprat Maria Fernanda Sanchez-Goni Frdrique Eynaud Karine Charlier Ralph Schneider Aloys Bory Viviane Bout Jose Abel Flores 《Quaternary Research》2007,68(3):379-386
It has been proposed that tropical events could have participated in the triggering of the classic, high-latitude, iceberg-discharge Heinrich events (HE). We explore low-latitude Heinrich events equivalents at high resolution, in a piston core recovered from the tropical north-western African margin. They are characterized by an increase of total dust, lacustrine diatoms and fibrous lacustrine clay minerals. Thus, low-latitude events clearly reflect severe aridity events that occurred over Africa at the Saharan latitudes, probably induced by southward shifts of the Inter Tropical Convergence Zone. At a first approximation, it seems that there is more likely synchronicity between the high-latitude Heinrich Events (HEs) and low-latitude events (LLE), rather than asynchronous behaviours. 相似文献