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Abstract. This contribution introduces MOBSY, a fully integrated, autonomous mobile service robot system. It acts as an automatic dialogue-based receptionist for visitors to our institute. MOBSY incorporates many techniques from different research areas into one working stand-alone system. The techniques involved range from computer vision over speech understanding to classical robotics. Along with the two main aspects of vision and speech, we also focus on the integration aspect, both on the methodological and on the technical level. We describe the task and the techniques involved. Finally, we discuss the experiences that we gained with MOBSY during a live performance at our institute.  相似文献   
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The trend in microelectronics toward printing features 0.25 μm and below has motivated the development of lithography at the 193-nm wavelength of argon fluoride excimer lasers. This technology is in its early stages, but a picture is emerging of its strengths and limitations. The change in wavelength from 248 to 193 nm will require parallel progress in projection systems, optical materials, and photo-resist chemistries and processes. This paper reviews the current status of these various topics as they have been engineered under a multiyear program at MIT Lincoln Laboratory  相似文献   
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Numerical simulations of the response of a uniform, cantilever beam subjected to a base excitation are performed. A saturation absorber is implemented to control the beam response. In previous investigations of similar configurations, the inertial and structural properties of the piezoelectric actuators have been neglected, resulting in an analytical model of a uniform beam. This investigation includes the nonuniformities in the beam properties that are introduced when piezoelectric actuators are bonded to the uniform beam. The resulting coupling between uniform, cantilever beam modes is fully included in the analytical model. It is shown that this modal coupling has a significant effect on the beam response, which is not present when modal coupling is neglected.  相似文献   
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The reduction of nitric oxide with ammonia on an unsupported iron oxide catalyst has been studied in a continuous-flow recycle reactor using simulated flue gas. The responses of the employed reactor system to step and pulse inputs of tracer indicate that the system could be regarded as a continuous stirred tank reactor (CSTR). Preliminary tests were carried out to determine the effect of temperature and particle size on the measured reaction rates. Additional experiments were performed in order to study the influence of oxygen and water concentration on these rates. A gas chromatographic system has been developed to analyze the gas components NO, N2O, NO2, NH3, H2O, O2, CO2 and N2. In addition, the concentrations of NO and NO2 were measured with a nondisperse infrared (NDUV/NDIR) analyzer.  相似文献   
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A new principle and arrangement for directly determining the angle of incidence of an optical beam on an object are proposed and demonstrated. The novelty of the approach lies in the realization of a ‘smart object’, which extracts a portion of the incident beam's power into an optical waveguide attached to the object's surface or embedded in its body for converting the angle of incidence into the position of a guided beam with finite lateral extent. This ‘integrated optical light pointer’ beam is accomplished by means of creating additional degrees of freedom on the target in two different ways. While a first type is based on introducing spatial variations of the waveguide thickness, a second type makes use of a chirp of the grating periodicity. The feasibility for practical applications has been experimentally demonstrated by a direct comparison with a commercial high-resolution encoder, resulting in an r.m.s. error of <30′'. Measurements have been performed for chips fabricated based on replicated polycarbonate substrates and with no external optics, showing the great potential of this approach for realizing low-cost yet high-performance miniature goniometers.  相似文献   
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本文提出用梯度有效折射率平面波导形成小型波导传感器的方案 ,对关键单元技术进行了分析和实验 ,给出了结构参数测量结果  相似文献   
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Ohne ZusammenfassungMitteilung aus der K.-k. allgemeinen Untersuchungsanstalt für Lebensmittel in Wien.  相似文献   
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Studies took place to investigate the effects of different nutrient conditions on the biosorption ability and selectivity of heavy metals by Saccharomyces cerevisiae. After having grown in media supplemented with additional glucose, ammonium, phosphate or cysteine, the yeast was exposed to an equimolar solution of lead, cadmium, zinc and copper. Lead removal from a mixed solution was significantly higher than that of copper, followed by zinc and cadmium. Generally, yeasts from cysteine-rich media showed greatest sorption capacity whereas phosphate addition influenced zinc selectivity. In addition, glucose, fructose and sucrose as carbon sources were examined. Cultures grown in glucose had a better uptake than those cultivated with fructose at an incubation time of 30 min.  相似文献   
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