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991.
Abstract

Cave paintings bear witness that, early in human cultural development, art and the means to create it (technology) became a method of expression and translation of human interconnectedness with nature defined as the non-human-made world. Contemporary new media artists interacting with nature through the medium of digital technologies in situ continue this exploration within the genre referred to as “digital eco-art”. LocoMotoArt, an independently powered creative field system, was used as a vehicle for conducting media arts practice in natural settings during a three-year qualitative field research project. Findings indicate that human–technology–nature interconnectedness is a possible conduit for establishing a role for digital technology beyond social networking, computing, information gathering and gaming to engage with nature. We argue that digital eco-artists are at the vanguard of creating a new sense of aesthetic and environmental engagement, proportions of which emerge as transformative possibilities. The art experience of digital eco-art can change from being a contemplative one to a living experience.  相似文献   
992.
Materials and technology development for designing innovative and efficient X‐ray radiation detectors is of utmost importance for a wide range of applications ranging from security to medical imaging. Here, highly sensitive direct X‐ray detectors based on novel cesium (Cs)‐based triple cation mixed halide perovskite thin films are reported. Despite being in a thin film form, the devices exhibit a remarkably high X‐ray sensitivity of (3.7 ± 0.1) µC Gy?1 cm?2 under short‐circuit conditions. At a small reverse bias of 0.4 V, the sensitivity further increases by orders of magnitude reaching a record value of (97 ± 1) µC Gy?1 cm?2 which surpasses state‐of‐the‐art inorganic large‐area detectors (a‐Se and poly‐CZT). Based on detailed structural, electrical, and spectroscopic investigations, the exceptional sensitivity of the triple cation Cs perovskite is attributed to its high ambipolar mobility‐lifetime product as well as to the formation of a pure stable perovskite phase with a low degree of energetic disorder, due to an efficient solution‐based alloying of individual n‐ and p‐type perovskite semiconductors.  相似文献   
993.
Multimedia Tools and Applications - Hidradenitis Suppurativa (HS), also known as Acne Inversa, is a chronic, underdiagnosed, often debilitating and painful disease that affects the folds of the...  相似文献   
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996.
The popularity of Interactive Digital Television (IDTV) applications has grown in recent years, playing a significant role in today’s society. This new type of television allows users to access interactive applications in order to look for information, for communication or educational purposes, or just for fun. Most of these applications require text entry and many users expect a user experience similar to that of computers. Although the most common device to interact with television is the conventional remote control, other devices available on the market may be used in this context. Thus, in this article we aim to evaluate and compare different text input methods for IDTV applications using devices alternative to conventional remote controls. We have carried out an empirical study with 52 participants. We analyze entry speeds, error rates, and subjective impressions for six different entry methods, taking into account the particular characteristics of the users. As devices we have used a full-sized keyboard, a palm-sized keyboard, a gyroscopic remote point-select, and a modified touchpad. The fastest method is the standard keyboard, but in an IDTV context many users report discomfort and problems under low lighting conditions. Also, error rates are considerably higher with both keyboards when modifier keys need to be used. The results obtained with the gyroscopic remote and the touchpad are similar. Nevertheless, while users complain about fatigue problems with the former, their feedback about the latter is very positive. We have also observed that age is a major factor affecting the performance of the users. We expect our results to contribute to the design of new text entry methods for IDTV.  相似文献   
997.
Both Petri nets and differential equations are important modeling tools for biological processes. In this paper we demonstrate how these two modeling techniques can be combined to describe biological gradient formation. Parameters derived from partial differential equation describing the process of gradient formation are incorporated in an abstract Petri net model. The quantitative aspects of the resulting model are validated through a case study of gradient formation in the fruit fly.  相似文献   
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999.

Sensitivity analysis of a model can identify key variables affecting the performance of the model. Uncertainty analysis is an essential indicator of the precision of the model. In this study, the sensitivity and uncertainty of the Long-Term Hydrologic Impact Assessment-Low Impact Development 2.1 (L-THIA-LID 2.1) model in estimating runoff and water quality were analyzed in an urbanized watershed in central Indiana, USA, using Sobol′‘s global sensitivity analysis method and the bootstrap method, respectively. When estimating runoff volume and pollutant loads for the case in which no best management practices (BMPs) and no low impact development (LID) practices were implemented, CN (Curve Number) was the most sensitive variable and the most important variable when calibrating the model before implementing practices. When predicting water quantity and quality with varying levels of BMPs and LID practices implemented, Ratio_r (Practice outflow runoff volume/inflow runoff volume) was the most sensitive variable and therefore the most important variable to calibrate the model with practices implemented. The output uncertainty bounds before implementing BMPs and LID practices were relatively large, while the uncertainty ranges of model outputs with practices implemented were relatively small. The limited observed data in the same study area and results from other urban watersheds in scientific literature were either well within or close to the uncertainty ranges determined in this study, indicating the L-THIA-LID 2.1 model has good precision.

  相似文献   
1000.

Objective

Signal drop-off occurs in echo-planar imaging in inferior brain areas due to field gradients from susceptibility differences between air and tissue. Tailored-RF pulses based on a hyperbolic secant (HS) have been shown to partially recover signal at 3 T, but have not been tested at higher fields.

Materials and methods

The aim of this study was to compare the performance of an optimized tailored-RF gradient-echo echo-planar imaging (TRF GRE-EPI) sequence with standard GRE-EPI at 7 T, in a passive viewing of faces or objects fMRI paradigm in healthy subjects.

Results

Increased temporal-SNR (tSNR) was observed in the middle and inferior temporal lobes and orbitofrontal cortex of all subjects scanned, but elsewhere tSNR decreased relative to the standard acquisition. In the TRF GRE-EPI, increased functional signal was observed in the fusiform, lateral occipital cortex, and occipital pole, regions known to be part of the visual pathway involved in face-object perception.

Conclusion

This work highlights the potential of TRF approaches at 7 T. Paired with a reversed-gradient distortion correction to compensate for in-plane susceptibility gradients, it provides an improved acquisition strategy for future neurocognitive studies at ultra-high field imaging in areas suffering from static magnetic field inhomogeneities.
  相似文献   
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