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331.
Remotely sensed surface water extent as an indicator of short-term changes in ecohydrological processes in sub-Saharan Western Africa 总被引:1,自引:0,他引:1
Eva Maria Haas Etienne Bartholomé Eric F. Lambin Veerle Vanacker 《Remote sensing of environment》2011,115(12):3436-3445
The highly variable rainfall in the arid and semi-arid regions of sub-Saharan Western Africa drives both surface water availability and vegetation cover. Recent studies have established linkages between rainfall and vegetation cover at local to regional scales, but no study related yet remote sensing derived rainfall and vegetation cover to the available surface water. A new dataset based on SPOT VEGETATION (VGT) represents surface water bodies (SWB) in the arid and semi-arid regions of sub-Saharan Western Africa. Water bodies represent the integrated hydrological response of a catchment, and changes in their spatial extent involve complex interactions at the catchment scale. We analyzed time series of remotely sensed vegetation cover, rainfall and surface water extent for the period 1999–2008, and could detect and statistically demonstrate the links between these biophysical variables. Our findings for two regions in Mali and Burkina Faso suggest that vegetation cover is positively related to the amount of available surface water for those catchments that are mainly covered by annual plants. The observed relationships between remotely sensed variables allow developing ecological indicators that can indicate short-term changes in arid and semi-arid ecosystems at local to regional scales. 相似文献
332.
Koji Kamei Kunihiko Fujita Eva Jettmar Sen Yoshida Kazuhiro Kuwabara 《Interacting with computers》2002,14(6):438-759
In this paper, we present and discuss Community Organizer, a system designed to support network communities. The main characteristic of Community Organizer is the use of spatial representations for the relationships among community members including the communications exchanged among these members. These spatial representations reflect the degree of closeness of interests and concerns among the members, and are intended to provide users with clues on how to form network communities. In order to investigate the effectiveness of the proposed spatial representations, we conducted experiments with two different versions of the software. One version offered meaningful spatial representations while the other version did not. The subjects who used the former software version felt a greater sense of ‘community’, enjoyed using the software more, and actively used it longer than the subjects using the latter software version (control condition). These results indicated that the proposed spatial representations are effective in supporting network community formation. 相似文献
333.
Per Carlbring Eva Björnstjerna Anna F. Bergström Johan Waara Gerhard Andersson 《Computers in human behavior》2007
This experimental analog component study compared two ways of administrating relaxation, either via a computer or by a therapist. The second phase of applied relaxation was used, which is called “release-only relaxation”. Sixty participants from a student population were randomized to one of three groups: computer-administered relaxation, therapist-administered relaxation, or a control group in which participants surfed on the Internet. Outcome was measures using psychophysiological responses and self-report. Objective psychophysiological data and results on the subjective visual analogue scale suggest that there was no difference between the two forms of administration. Both experimental groups became significantly more relaxed than the control group that surfed on the Internet. Practical applications and future directions are discussed. 相似文献
334.
Matthias Schirmer Doris Perseke Eva Zena Daniel Schondelmaier Ivo Rudolph Bernd Loechel 《Microsystem Technologies》2007,13(3-4):335-338
A variety of different photo resists are used for fabrication of MEMS. Presently good results were reported for SU-8, a chemically
amplified negative tone photoresist. But SU-8 has a disadvantage for some applications in LIGA technique, especially in the
X-ray mask fabrication. After processing the finished resist pattern are hardly soluble from the substrate. This paper will
briefly describe the current status of the development of the new negative tone photoresist CAR 44 whose big advantage is
the easy removableness of the cross linked pattern.
This work widely uses the contents of the presentation “A New Removable Resist for High Aspect Ratio Applications” to the
High Aspect Ratio Micro Structure Technology workshop HARMST 2005 held in Gyeongyu (Republic of Korea), June 10–13, 2005. 相似文献
335.
Non-linear diffusion (ND) is an iterative difference equation used in several image processing applications such as denoising, segmentation, or compression. The number of iterations required to achieve optimal processing can be very high, making ND not suitable for real-time requirements. In this paper, we study how to reduce complexity of ND so as to achieve minimal number of iterations for real-time image denoising. To do this, we first study the relations between parameters of the iterative equation: the number of iterations, the time step, and the edge strength. We then proceed by estimating the minimally required number of iterations to achieve effective denoising. Then, we relate the edge strength to the number of iterations, to noise, and to the image structure. The resulted minimal iterativity ND is very fast, while still achieves similar or better noise reduction compared to related ND work. This paper also shows how the proposed spatial filter is suitable for structure-sensitive object segmentation and temporal noise reduction. 相似文献
336.
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338.
Based on social role theory and uses and gratifications, this study provides insights into the popularity of so-called pink games. This study is the first to examine the roles of identification, playing time, and age in the experience of motivations while playing an online role-playing game. Drawing upon a survey among 2261 girls between10 and 17 of age, our results show that identification with characters in the game is an important process in explaining girls’ gaming motivations. In addition, identification and motivations are intensified with playing time. Although age affects identification negatively, age is not related to the most important motive in playing pink games: social interaction. This study has important theoretical and practical implications for the popularity of pink games among girls. 相似文献
339.
The Early Bird Gets the Worm,But the Second Mouse Gets the Cheese: Non‐Technological Innovation in Creative Industries 下载免费PDF全文
In the context of economic turmoil, firms in the creative industries (CIs) must make fast decisions as to when to break through with innovations. This paper discusses non‐technological, organizational innovation of early‐adopters, first movers and early followers in order to overcome persistent economic decline, and the implication of different strategies for innovation success. The strategic principle of the pioneer's advantage rests on pre‐emption – the premise that ‘the early bird gets the worm’ and this often applies to business model innovation (BMI). ‘But the second mouse gets the cheese’ points at early followers who may have a more systematic, strategic approach towards innovation. Greater understanding of the advantages of each strategic approach and their significance for innovation performance is critical for CIs where unpredictability and the accelerating pace of change pervade the decisions concerning innovation. Drawing on five exemplary cases of archaeological firms in Spain, this paper explores different innovation process dynamics. The study develops a contingency model where pioneers who challenge their current business model, may be outperformed by early followers who incorporate complementary management innovation (MI) initiatives into the BMI. 相似文献
340.
Thomas O.J. Blomfeldt Richard T. Olsson Mohan Menon David Plackett Eva Johansson Mikael S. Hedenqvist 《大分子材料与工程》2010,295(9):796-801
A new way of producing rigid or semi‐rigid foams from vital wheat gluten using a freeze‐drying process is reported. Water/gluten‐based mixtures were frozen and freeze‐dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol or bacterial cellulose nanofibers. MIP revealed that the foams had mainly an open porosity peaking at 93%. The average pore diameter ranged between 20 and 73 µm; the sample with the highest wheat gluten concentration and no plasticizer had the smallest pores. Immersion tests with limonene revealed that the foams rapidly soaked up the liquid. An especially interesting feature of the low‐wheat‐concentration foams was the “in situ” created soft‐top‐rigid‐bottom foams.