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161.
Hong Lai Mehmet A. Orgun Josef Pieprzyk Jing Li Mingxing Luo Jinghua Xiao Fuyuan Xiao 《Quantum Information Processing》2016,15(11):4663-4679
We propose an approach that achieves high-capacity quantum key distribution using Chebyshev-map values corresponding to Lucas numbers coding. In particular, we encode a key with the Chebyshev-map values corresponding to Lucas numbers and then use k-Chebyshev maps to achieve consecutive and flexible key expansion and apply the pre-shared classical information between Alice and Bob and fountain codes for privacy amplification to solve the security of the exchange of classical information via the classical channel. Consequently, our high-capacity protocol does not have the limitations imposed by orbital angular momentum and down-conversion bandwidths, and it meets the requirements for longer distances and lower error rates simultaneously. 相似文献
162.
163.
Signage Versus Environmental Affordances: Is the Explicit Information Strong Enough to Guide Human Behavior During a Wayfinding Task?
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Elisângela Vilar Francisco Rebelo Paulo Noriega Júlia Teles Christopher Mayhorn 《人机工程学与制造业中的人性因素》2015,25(4):439-452
This study aims to explore how people behave when they have to find a location within a complex building and are confronted with situations where directional signage (i.e., explicit information) is in opposition to environmental affordances that naturally direct users towards a specific path, creating a situation with conflicting information (e.g., a brighter corridor vs. a darker corridor but with a directional sign indicating to follow the darker one). A virtual reality–based methodology was used and a between‐subject design was considered. Thus, participants were given the tasks of finding three publicly accessible central points in a virtual hotel and confronted with a two forced‐choice task of local scenes in which environmental variables (i.e., corridor width and brightness) and signage varied systematically, in two experimental conditions (i.e., neutral and signage). For the signage condition, signs were inserted to explicitly point in the opposite direction than that implicitly suggested by the environmental affordances, creating situations with conflicting information. Results indicate that environmental variables were able to direct people indoors acting as environmental affordances. Users preferred to follow the wider and brighter paths. However, when directional signage pointed in the opposite direction of the paths preferred by the participants, most of them complied with signage. 相似文献
164.
Clarke DT Botchway SW Coles BC Needham SR Roberts SK Rolfe DJ Tynan CJ Ward AD Webb SE Yadav R Zanetti-Domingues L Martin-Fernandez ML 《The Review of scientific instruments》2011,82(9):093705
Optics clustered to output unique solutions (OCTOPUS) is a microscopy platform that combines single molecule and ensemble imaging methodologies. A novel aspect of OCTOPUS is its laser excitation system, which consists of a central core of interlocked continuous wave and pulsed laser sources, launched into optical fibres and linked via laser combiners. Fibres are plugged into wall-mounted patch panels that reach microscopy end-stations in adjacent rooms. This allows multiple tailor-made combinations of laser colours and time characteristics to be shared by different end-stations minimising the need for laser duplications. This setup brings significant benefits in terms of cost effectiveness, ease of operation, and user safety. The modular nature of OCTOPUS also facilitates the addition of new techniques as required, allowing the use of existing lasers in new microscopes while retaining the ability to run the established parts of the facility. To date, techniques interlinked are multi-photon/multicolour confocal fluorescence lifetime imaging for several modalities of fluorescence resonance energy transfer (FRET) and time-resolved anisotropy, total internal reflection fluorescence, single molecule imaging of single pair FRET, single molecule fluorescence polarisation, particle tracking, and optical tweezers. Here, we use a well-studied system, the epidermal growth factor receptor network, to illustrate how OCTOPUS can aid in the investigation of complex biological phenomena. 相似文献
165.
166.
Yan Zhang Sheela Surisetty Christopher Scaffidi 《Journal of Visual Languages and Computing》2013,24(5):313-326
Visual languages have been widely used to help people create animation programs. However, current programming environments lack features supporting efficient code exploration and program comprehension, particularly for understanding relationships among parts of animation programs. In this paper, we present novel interactive visualizations aimed at helping people to understand animation programs. We conducted an empirical study to evaluate the impact of these visualizations on programmer comprehension of the code, showing that our approach enabled programmers to comprehend more information with less effort and in less time. This result is potentially significant because it demonstrates an approach for helping users to explore and understand animation code. We anticipate that this approach could be applied in a wide variety of animation programming tools, which could ease common animation programming tasks that require understanding code. 相似文献
167.
Varol O. Kayhan Christopher J. Davis Rosann Webb Collins Anol Bhattacherjee 《Information Systems Management》2013,30(2):168-178
Two mechanisms that verify knowledge contributions in electronic repositories are expert-governance and community-governance. Our goal is to examine repository users' perceptions of the conditions under which these mechanisms verify knowledge contributions. Qualitative data show that perceived credibility of experts, perceived ownership of content, and experts' (meticulous) execution of governance functions are salient for expert-governance, and the perceived involvement of community members, and community members' (continuous and collective) execution of governance functions are important for community-governance. 相似文献
168.
169.
Peter D. Blanken Christopher Spence Newell Hedstrom John D. Lenters 《Journal of Great Lakes research》2011,37(4):707-716
The surface energy balance of Lake Superior was measured using the eddy covariance method at a remote, offshore site at 0.5-h intervals from June 2008 through November 2010. Pronounced seasonal patterns in the surface energy balance were observed, with a five-month delay between maximum summer net radiation and maximum winter latent and sensible heat fluxes. Late season (winter) evaporation and sensible heat losses from the lake typically occurred in two- to three-day-long events, and were associated with significant release of stored heat from the lake. The majority of the evaporative heat loss (70-88%) and sensible heat loss (97-99%) occurred between October and March, with 464 mm (2008-2009) and 645 mm (2009-2010) of evaporative water loss occurring over the water year starting October 1. Evaporation was proportional to the horizontal wind speed, inversely proportional to the ambient vapor pressure, and was well described by the ratio of wind speed to vapor pressure. This ratio remained relatively constant between the two water years, so the differences in evaporative water loss between years were largely associated with differences in lake surface conditions (e.g. water temperature, ice cover, and ice duration). Since late-season water temperature decline is driven by evaporative and sensible heat loss, the potential for a negative feedback mechanism between evaporation and ice cover is discussed. 相似文献
170.
Naizhuo Zhao Tilottama Ghosh Nathan Allen Currit Christopher D. Elvidge 《Water Resources Management》2011,25(9):2241-2250
Global water resources are vulnerable to depletion due to the increasing demand of an ever-increasing human population. A
country’s water footprint is a measure of the total volume of water needed to produce the goods and services consumed by the
country, including water originating beyond its own borders. The water footprint can be a critical indicator of global water
resource use, but its practical application is hindered by a lack of comparable data across national boundaries. The purpose
of this article is to test the applicability of the nighttime imagery products produced by the Defense Meteorological Satellite
Program’s Operational Linescan System (DMSP-OLS) for the assessment of the global water footprint. To accomplish this purpose,
the average areal extent of nighttime lighting (lit area) is calculated from 1997 to 2001. Next, lit area is regressed on
the total water footprint for each country, as indicated by the Water Footprint Network (WFN), to estimate that country’s
total water footprint using nighttime imagery. Model residuals are analyzed at the national scale to understand the appropriateness
of nighttime imagery for assessing water consumption. Results indicate strong positive correlations between lit area and total
water footprint (TWF), domestic water withdrawal (DWW), and industrial water consumption (IWC) at the national scale. Overall,
the analyses reveal that the rate of agricultural water consumption to total water footprint (AWCR) and population density
can affect the precision of estimates when lit area is selected as a proxy to estimate water footprints. 相似文献