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41.
Ronald Poppe Khiet P. Truong Dirk Heylen 《Autonomous Agents and Multi-Agent Systems》2013,27(2):235-253
Artificial listeners are virtual agents that can listen attentively to a human speaker in a dialog. In this paper, we present two experiments where we investigate the perception of rule-based backchannel strategies for artificial listeners. In both, we collect subjective judgements of humans who observe a video of a speaker together with a corresponding animation of an artificial listener. In the first experiment, we evaluate six rule-based strategies that differ in the types of features (e.g. prosody, gaze) they consider. The ratings are given at the level of a speech turn and can be considered a measure for how human-like the generated listening behavior is perceived. In the second experiment, we systematically investigate the effect of the quantity, type and timing of backchannels within the discourse of the speaker. Additionally, we asked human observers to press a button whenever they thought a generated backchannel occurrence was inappropriate. Both experiments together give insights in the factors, both from an observation and generation point-of-view, that influence the perception of backchannel strategies for artificial listeners. 相似文献
42.
Park ND Thring RW Garton RP Rutherford MP Helle SS 《Water science and technology》2011,64(9):1851-1856
Anaerobic digestion is a well established technology for the reduction of organic matter and stabilization of wastewater. Biogas, a mixture of methane and carbon dioxide, is produced as a useful by-product of the process. Current solid waste management at the city of Prince George is focused on disposal of waste and not on energy recovery. Co-digestion of fresh fruit and vegetable waste with sewer sludge can improve biogas yield by increasing the load of biodegradable material. A six week full-scale project co-digesting almost 15,000 kg of supermarket waste was completed. Average daily biogas production was found to be significantly higher than in previous years. Digester operation remained stable over the course of the study as indicated by the consistently low volatile acids-to-alkalinity ratio. Undigested organic material was visible in centrifuged sludge suggesting that the waste should have been added to the primary digester to prevent short circuiting and to increase the hydraulic retention time of the freshly added waste. 相似文献
43.
Félix Gómez Mármol Christoph Sorge Ronald Petrlic Osman Ugus Dirk Westhoff Gregorio Martínez Pérez 《International Journal of Information Security》2013,12(2):67-82
The recent deployment of smart grids promises to bring numerous advantages in terms of energy consumption reduction in both homes and businesses. A more transparent and instantaneous measurement of electricity consumption through smart meters utilization leads to an enhancement in the ability of monitoring, controlling and predicting energy usage. Nevertheless, it also has associated drawbacks related to the privacy of customers, since such management might reveal their personal habits, which electrical appliances they are using at each moment, whether they are at home or not, etc. In this work, we present a privacy-enhanced architecture for smart metering aimed at tackling this threat by means of encrypting individual measurements while allowing the electricity supplier to access the aggregation of the corresponding decrypted values. 相似文献
44.
Image mosaic construction is about stitching together a number of images about the same scene to construct a single image with a larger field of view. The majority of the previous work was rooted at the use of a single image-to-image mapping termed planar homography for representing the imaged scene. However, the mapping is applicable only to cases where the imaged scene is either a single planar surface, or very distant from the cameras, or imaged under a pure rotation of the camera, and that greatly limits the range of applications of the mosaicking methods. This paper presents a novel mosaicking solution for scenes that are polyhedral (thus consisting of multiple surfaces) and that are pictured possibly in closed range of the camera. The solution has two major advantages. First, it requires only a few correspondences over the entire scene, not correspondences over every surface patch in it to work. Second, it conquers a seemingly impossible task—warping image data of surfaces that are visible in only one of the input images, which we refer to as the singly visible surfaces, to another viewpoint to constitute the mosaic there. We also provide a detail analysis of what determines whether a singly visible surface could be mosaicked or not. Experimental results on real image data are presented to illustrate the performance of the method. 相似文献
45.
It has been a common consensus that general techniques for stabilization of nonlinear systems are available only for some
special classes of nonlinear systems. Control design for nonlinear systems with uncertain components is usually carried out
on a per system basis, especially when physical control constraints, and certain control performance measures such as optimum
time control are imposed. Elegant adaptive control techniques are difficult to apply to this type of problems. A new neural
network based control design is proposed and presented in this paper to deal with a special class of uncertain nonlinear systems
with multiple inputs. The desired system dynamics are analyzed and utilized in the process of the proposed intelligent control
design. The theoretical results are provided to justify the design procedures. The simulation study is conducted on a second-order
bilinear system with two inputs and uncertainties on its parameters. The simulation results indicate that the proposed design
approach is effective. 相似文献
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49.
Ronald S. Cok John W. Hamer Christopher A. Bower Etienne Menard Salvatore Bonafede 《Journal of the Society for Information Display》2011,19(4):335-341
Abstract— Small integrated circuits of crystalline silicon (chiplets) transfer‐printed onto a flat‐panel‐display substrate provide greatly improved electrical performance and uniformity in active‐matrix organic light‐emitting‐diode (OLED) displays. The integrated circuits are formed in high‐performance crystalline silicon using conventional photolithographic processes and then transfer‐printed onto a substrate using a stamp that transfers hundreds or thousands of chiplets at once. The chiplets are connected to an external controller and to pixel elements using conventional photolithographic substrate processing methods. Active‐matrix OLED (AMOLED) displays using transfer‐printed chiplets have good yields, excellent uniformity, and electrical performance and are thermally robust. 相似文献
50.
Even though there is abundant literature on successful cases of organizations applying knowledge management (KM) measures,
many KM initiatives have failed to achieve their knowledge and business goals. In order to foster decisions about the design
of such initiatives, information is required on success factors and barriers when selecting KM measures. Multi agent-based
simulation (MABS) is suggested as instrument to investigate potential effects of KM measures on dependent variables such as
sharing of knowledge in organizations or business performance. For such a simulation, the concept of knowledge sharing, influencing
factors and their impact on business and knowledge goals are modeled based on an extensive multi-disciplinary literature survey.
An extensive domain model is operationalized in a simulation model which is then further simplified and implemented in a MABS
tool used for a series of experiments contrasting results with/without KM measures, specifically skill and experience management.
Skill management is found highly sensitive with respect to conditions of application and has no significant impact on knowledge
or business goals. Experience management positively impacts knowledge and business goals. Personal documentation leads to
specialist, project debriefings to generalist knowledge workers. Finally, the paper discusses the simulation’s limitations
and further areas of application. 相似文献