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91.
Lesa Lorenzen Huber Kalpana Shankar Kelly Caine Kay Connelly L. Jean Camp Beth Ann Walker 《International journal of human-computer interaction》2013,29(7):441-455
In-home technologies can support older adults' activities of daily living, provide physical safety and security, and connect elders to family and friends. They facilitate aging in place while reducing caregiver burden. One of older adults' primary concerns about in-home technologies is their potential to reduce human contact, particularly from cherished caregivers. In this exploratory in situ study, we provided an ecosystem of networked monitoring technologies to six older adults and their caregivers. We analyzed the amount and content of communication between them. The amount of noncomputer-mediated communication did not decrease through the 6-week study. The content of communication coalesced into four themes: communication about the technologies, communication facilitated by technologies, intrusiveness of technologies, and fun and playfulness with the technologies. Results suggest that in-home technologies, designed with sensitivity to older adults' primary motivations, have the potential to shape and tailor important relationships in later life. 相似文献
92.
93.
Jean Sykes 《New Review of Information Networking》2013,18(1):23-30
This article begins by looking at changes in the student body in recent years as useful indicators of how libraries need to alter and adapt their student library provision. Among the concepts explored are the student as consumer-customer, the Google generation, greater than ever competition among students especially for the job market, new technology as fashion accessory as much as learning tool, the widening participation agenda for higher education, and the almost ubiquitous presence of multi-functional electronic devices. There is an examination of some challenges for librarians in meeting the needs and demands of this new generation of students. These include the balancing of electronic and print provision, the future of the physical library environment, push rather than pull to deliver library services, anytime anywhere access to information, integration with other university services, and helping to fit students for the world of work. The main message of the article is that librarians are not under threat from the giant search engines as long as they embrace the interactive technologies which students so willingly and expertly use, and adapt them to get library services out to students as customers. 相似文献
94.
Nadia Magnenat Thalmann Igor Sunday Pandzic Jean‐Claude Moussaly 《Digital Creativity》2013,24(2):59-66
Abstract This paper describes the making of a short film on the Xian terra‐cotta soldiers using our integrated HU‐MANOID software. The method of creating and animating the soldiers’ faces is first presented. Then, we show how our approach, based on metaballs and spline surfaces, was used for designing and deforming soldiers’ bodies. For the animation of the bodies, we describe the motion control methods. Clothes for the soldiers are then described as well as horses and decor design. For the rendering, we explained our strategy using parallel machines. Finally, problems of integration are addressed. 相似文献
95.
Sustainable water management is a global challenge for the 21st century. One key aspect remains protection against urban flooding. The main objective is to ensure or maintain an adequate level of service for all inhabitants. However, level of service is still difficult to assess and the high-risk locations difficult to identify. In this article, we propose a methodology, which (i) allows water managers to measure the service provided by the urban drainage system with regard to protection against urban flooding; and (ii) helps stakeholders to determine effective strategies for improving the service provided. One key aspect of this work is to use a database of sewer flood event records to assess flood risk. Our methodology helps urban water managers to assess the risk of sewer flooding; this approach does not seek to predict flooding but rather to inform decision makers on the current level of risk and on actions which need to be taken to reduce the risk. This work is based on a comprehensive definition of risk, including territorial vulnerability and perceptions of urban water stakeholders. This paper presents the results and the methodological contributions from implementing the methodology on two case studies: the cities of Lyon and Mulhouse. 相似文献
96.
Streamflow Simulation by SWAT Using Different Precipitation Sources in Large Arid Basins with Scarce Raingauges 总被引:2,自引:1,他引:1
Meiyan Yu Xi Chen Lanhai Li Anming Bao Mupenzi Jean de la Paix 《Water Resources Management》2011,25(11):2669-2681
Streamflow from the mountains is the main source of water for the lower plain in arid regions. Accurate simulation of streamflow
is of great importance to the arid ecosystem. However, many large arid drainage basins in northwestern China have low density
of precipitation stations, which makes the streamflow modeling and prediction very difficult. Based on raingauge data and
Tropical Rainfall Measuring Mission (TRMM) data combined with raingauge data, different approaches were explored for spatializing
precipitation in large area with scarce raingauges. Spatialized precipitation was then input into Soil and Water Assessment
Tool (SWAT), a semi-distributed hydrological model, to simulate streamflow. Results from a case study in the Manas river basin
showed that simulated hydrographs using both the approaches are able to reproduce the watershed hydrological behavior. Moreover,
statistical assessment indicated that hydrological model driven by the spatialized precipitation based on radar combined with
raingauge data performed better than that based on gauge data. Radar precipitation estimator can provide a practical data
source for hydrological modeling at a basin scale where the raingauge network is sparse. 相似文献
97.
Juan Manuel González Calleros Josefina Guerrero García Jean Vanderdonckt 《Universal Access in the Information Society》2013,12(4):387-401
The need for accessibility evaluation tools is motivated by several endogenous and exogenous reasons coming from the end user (the designer and the developer) and companies releasing information systems. Existing evaluation tools mainly concentrate on examining the code of Web pages: Web pages more and more frequently contain non-HTML parts that entirely escape from being treated by existing techniques. This is the case of the advanced human–machine interface (AHMI), a piece of software programmed in C/C++, used for controlling the advanced flight management system in the aircraft cockpit. Studying this new user interface (UI) requires a structured approach to evaluate and validate AHMI designs. The goal in this work is to develop an evaluation tool to automate the process of evaluating the AHMI. The method addresses: support of multiple bases of guidelines (accessibility or usability or both) on-demand (partial or total evaluation), with different levels of details (a presentation for developers and for those responsible for certifying accessibility). The method goes a step toward the automatic evaluation of UI containing non-HTML parts. 相似文献
98.
The Sanaga River is one of Sub‐Saharan Africa's largest and greatly regulated rivers. Available flow data for this hydrosystem largely cover the pre‐ and post‐regulation periods. From comparisons between unregulated (hypothetical) and observed scenarios, it has been possible to separate and to quantify hydro‐climatic (groundwater + rainfall) change effects from anthropogenic impacts (especially dam‐related alterations). To appreciate shifts in the river regime, discontinuity detection tests and the IHA model were applied to discharge data series reflecting average and extreme flow conditions, respectively. Results obtained principally from the Hubert segmentation method reveal that a major discontinuity occurred in 1970–1971 separating a surplus phase between 1945–1946 and 1969–1970, and a deficient and much contrasted one, from 1971/1972. This implies that the Sanaga catchment is dominantly affected by hydro‐climatic changes. However, wide land cover/land use changes experienced here since 1988 have resulted in an increase in surface runoff. Additional quickflows linked to these changes may have partly compensated for the substantial decline in the dry season rainfall and groundwater inputs observed from this date. Although at the monthly scale, dam‐related impacts on average flows increase with stage of regulation, the seasonal variability of the river regime remains generally unaffected. A comparison of the IHA statistics, calculated from unregulated and observed streamflow data, show that hydrologic shifts occurring in maximum and minimum discharges are mostly significant from 1971/1972 and are mainly due to the action of dams. Minimum flows appear, however, widely impacted, thus reflecting the prime objective assigned to the existing reservoirs, constructed to supplement flows for hydroelectricity production during the dry season. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
99.
Estimation of soil clay and calcium carbonate using laboratory, field and airborne hyperspectral measurements 总被引:2,自引:0,他引:2
Philippe Lagacherie Frédéric Baret José Madeira Netto Jean Marc Robbez-Masson 《Remote sensing of environment》2008,112(3):825-835
This paper examines how reflectance spectrometry used in the laboratory to estimate clay and calcium carbonate (CaCO3) soil contents can be applied to field and airborne measurements for soil property mapping. A continuum removal (CR) technique quantifying specific absorption features of clay (2206 nm) and CaCO3 (2341 nm) was applied to laboratory, field and airborne HYMAP reflectance measurements collected in 2003 (33 sites) and 2005 (19 sites) over bare soil sites of a few meters within the La Peyne Valley area, southern France. Nine intermediate stages from the laboratory up to HYMAP sensor measurements were considered for separately evaluating the possible degradation of estimation performances when going across scales and sensors, e.g. radiometric calibration, spectral resolution, spatial variability, illumination conditions, and surface status including roughness, soil moisture and presence and nature of pebbles.Significant relationships were observed between clay and CaCO3 contents and CR values computed respectively at 2206 nm and 2341 nm from reflectance measurements at the laboratory level with an ASD spectrophotometer up to the HYMAP spectro-imaging sensor. Performances of clay and CaCO3 estimations decreased from the laboratory to airborne scales. The main factors inducing uncertainties in the estimates were radiometric and wavelength calibration uncertainties of the HYMAP sensor as well as possible residual atmospheric effects. 相似文献
100.
Recent progress in modelling, animation and rendering means that rich, high fidelity virtual worlds are found in many interactive graphics applications. However, the viewer's experience of a 3D world is dependent on the nature of the virtual cinematography, in particular, the camera position, orientation and motion in relation to the elements of the scene and the action. Camera control encompasses viewpoint computation, motion planning and editing. We present a range of computer graphics applications and draw on insights from cinematographic practice in identifying their different requirements with regard to camera control. The nature of the camera control problem varies depending on these requirements, which range from augmented manual control (semi‐automatic) in interactive applications, to fully automated approaches. We review the full range of solution techniques from constraint‐based to optimization‐based approaches, and conclude with an examination of occlusion management and expressiveness in the context of declarative approaches to camera control. 相似文献