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91.
Nitrous oxide (N2O) is a powerful greenhouse gas. As the UK government is committed to reducing greenhouse gas emissions, it is important to know not only how much of these gases are released but also where and when. Targeted measurements of emissions in relation to crop growth cycles, soil wetness and fertiliser applications were used to derive annual emission rates for specific combinations of soil type, land management and fertiliser practices. These annual emission rates were then spatially scaled to derive regional figures through the development of a Geographic Information System (GIS) based model framework. Digital soil and land use maps at a scale of 1:25000 for two test areas of approximately 200000 ha each (Lothians and the Ayrshire Basin) were overlain with a climate map within the GIS, deriving unique combinations of soil wetness and land use. The calculated annual emission rates (kg N ha–1 yr–1) were then applied to these and multiplied by the total area of each soil/land use type to derive annual emission losses for each area. The annual emission of nitrous oxide from the Lothians was determined as approximately 381000 kg N yr–1, while the emissions from the Ayrshire Basin were predicted to be 794000 kg N yr–1. This indicates the increased emissions associated with both the wetter soils of Ayrshire and the greater extent of grazed pasture systems in this area. Due to the detailed scale of the input data, localised areas with large emissions were identified. Abatement strategies would be concentrated on areas of high emissions that include a change to crops with lower emission potential, reducing fertiliser and manure inputs, reducing grazing intensity and improving soil drainage.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1024422604493 相似文献
92.
93.
The corrective reaction time (tcr) is an essential motor property when modelling hand control movements. Many studies designed experiments to estimate tcr, but reported only group means with inconsistent definitions. This study proposes an alternative methodology using Drury's (1994) intermittent illumination model. A total of 24 participants performed circular tracking movements under five levels of visual information delay using a modified monitor in a darkened room. Measured movement speeds and the manipulated delays were used with the model to estimate tcr of individuals and test effects of gender and path width. The results showed excellent model fits and demonstrated individual differences of tcr, which was 273 ms on average and ranged from 87 to 441 ms. The wide range of tcr values was due to significant effects of gender and path width. Male participants required shorter tcr compared to female participants, especially for narrow path widths. 相似文献
94.
The effectiveness of an active shutter-glasses stereoscopic display (SD) and a passive polarised SD was evaluated in a live robot-teleoperation task and a simulated indirect-vision driving task in various terrains. Overall, participants completed their tasks significantly faster with the SDs in three-dimensional (3D) mode than with the SDs in the baseline 2D mode. They also navigated more accurately with the SDs in 3D mode. When the effectiveness of the two types of SDs was examined separately, results showed that the active shutter-glasses SD resulted in faster responses and task completion times than the passive polarised SD, though most of the differences failed to reach statistical significance. Perceived workload when interacting with the two SD systems did not differ significantly between the active versus passive display types or between the 3D and 2D modes of operation; however, participants reported more severe discomfort after interacting with the passive polarised SD. 相似文献
95.
Mickaël Causse Roland Alonso François Vachon Robert Parise Jean-Pierre Orliaguet Sébastien Tremblay 《Ergonomics》2014,57(11):1616-1627
This study aims to determine whether indirect touch device can be used to interact with graphical objects displayed on another screen in an air traffic control (ATC) context. The introduction of such a device likely requires an adaptation of the sensory-motor system. The operator has to simultaneously perform movements on the horizontal plane while assessing them on the vertical plane. Thirty-six right-handed participants performed movement training with either constant or variable practice and with or without visual feedback of the displacement of their actions. Participants then performed a test phase without visual feedback. Performance improved in both practice conditions, but accuracy was higher with visual feedback. During the test phase, movement time was longer for those who had practiced with feedback, suggesting an element of dependency. However, this ‘cost’ of feedback did not extend to movement accuracy. Finally, participants who had received variable training performed better in the test phase, but accuracy was still unsatisfactory. We conclude that continuous visual feedback on the stylus position is necessary if tablets are to be introduced in ATC. 相似文献
96.
《Expert systems with applications》2014,41(2):644-654
This study aims to improve the general flood vulnerability approach using fuzzy TOPSIS based on α-cut level sets which can reduce the uncertainty inherent in even fuzzy multi-criteria decision making process. Since fuzzy TOPSIS leads to a crisp closeness for each alternative, it is frequently argued that fuzzy weights and fuzzy ratings should be in fuzzy relative closeness. Therefore, this study used a modified α-cut level set based fuzzy TOPSIS to develop a spatial flood vulnerability approach for Han River in Korea, considering various uncertainties in weights derivation and crisp data aggregation. Two results from fuzzy TOPSIS and modified fuzzy TOPSIS were compared. Some regions which showed no or small ranking changes have their centro-symmetric distributions, while other regions whose rankings varied dynamically, have biased (anti-symmetric) distributions. It can be concluded that α-cut level set based fuzzy TOPSIS produce more robust prioritization since more uncertainties can be considered. This method can be applied to robust spatial vulnerability or decision making in water resources management. 相似文献
97.
This pilot study focuses on the use real‐time visual feedback technology (VFT) in vocal training. The empirical research has two aims: to ascertain the effectiveness of the real‐time visual feedback software ‘Sing & See’ in the vocal training of pre‐service music teachers and the teachers' perspective on their experience with VFT. Forty participants from an undergraduate music teacher education programme were randomly assigned to three groups. The first two groups were assigned the teacher and student versions of Sing & See, respectively, and the third group served as a control group without access to the software. The experimental groups were given 12 weeks to use the software for vocal training on a self‐regulated basis. The technique of complex selections (TCS) was designed to assess the pitch accuracy and richness of vocal timbre. Pre‐ and post‐test singing tasks showed that the participants from the experimental groups significantly improved their vocal timbre. A questionnaire survey conducted after the training period found that most of the participants in the experimental s were positive about the effectiveness of VFT software in vocal training. As future leaders in the implementation of music education technology, pre‐service music teachers expressed a positive attitude towards the use of VFT as a technology‐enhanced learning (TEL) component in music education. 相似文献
98.
Ian Turk Matthew Sin Xin''an Zhou Jun Tao Chaoli Wang Qi Liao 《International Journal of Software and Informatics》2016,10(3)
We present a visual analytics system to understand the operation data of a
company, GAStech, from IEEE VAST Challenge 2016. The data include proximity data
recording the locations and movements of employees, and heating, ventilation, and air
conditioning (HVAC) data recording the environmental conditions in the building.
Analyzing the data to detect the suspicious behaviors of some disgruntled employees is of
special interest. Our system provides coordinated multiple views to visualize the proximity
data and the HVAC data over time. Visual hints and comparisons are designed for users to
identify abnormal patterns and compare them. Furthermore, the system automatically
detects and correlates the anomalies in the data. We provide use cases to demonstrate the
effectiveness of our system. 相似文献
99.
通过云浮硫铁矿计算机动态管理系统的开发,总结出一般矿山企业物资计算机管理系统在开发过程中应注意的问题,为其它矿山企业物资计算机动态管理系统的开发提供了有益的经验。 相似文献
100.
This paper presents a dynamic compensation concept to grapple with the dynamic defects of a traditional robot arm, especially while performing high-speed endpoint regulations. The proposed high-speed dynamic compensation concept offers a new point of view for cooperating with a traditional manipulator to realize highly dexterous performance of manipulations. The concept is realized through adoption of a high-speed light-weight actuator as well as endpoint closed loop configured high-speed cameras. The dynamic compensation is analyzed experimentally with 1000 Hz visual feedback and a high-speed finger for a robot arm in the case of one degree of freedom. The advantage of the proposed approach is that the modeling for the robot system’s dynamics is not needed, whereas it is necessary and trivial in order to realize high-speed regulations by traditional approaches. Thus, the control issue becomes easier with the proposed approach. As an application for this concept, fast peg-and-hole alignment with large position and attitude uncertainty is studied. The alignment algorithm is based on a visual compliance strategy. Alignment experiments show that with the proposed concept of dynamic compensation as well as visual compliant motion control, robust and fast convergence was realized for most cases. 相似文献