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191.
A six-degree-of-freedom industrial robot to which was added a number of sensors-vision, range, sound, proximity, force/torque, and touch-to enhance its inspection and manipulation capabilities is described. The work falls under the scope of partial autonomy. In teleoperation mode, the human operator prepares the robotic system to perform the desired task. Using its sensory cues, the system maps the workspace and performs its operations in a fully autonomous mode. Finally, the system reports back to the human operator on the success or failure of the task and resumes its teleoperation mode. The feasibility of realistic autonomous robotic inspection and manipulation tasks using multisensory information cues is demonstrated. The focus is on the estimation of the three-dimensional position and orientation of the task panel and the use of other nonvision sensors for valve manipulation. The experiment illustrates the need for multisensory information to accomplish complex, autonomous robotic inspection and manipulation tasks 相似文献
192.
Studies on the recovery of aflatoxin B1 injection into frozen beef at different intervals of storage
Tallury R. K. Murthy Mongi Jemmali Roland Rosset 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1975,158(1):5-7
Summary Beef stored at –18° C for 20, 25, 32, 153, and 183 days showed a diminution in the recovery of injected aflatoxin B1. An unusual passing of aflatoxin in ether and hexane fractions of silica gel column was noted. Ether fraction contained aflatoxin B1-like substance from stored beef samples. Probable occlusion of aflatoxin B1 to meat constituents due to physico-chemical changes associated with muscle during storage was discussed.
Studien über die Wiederfindungsrate von in gefrorenem Rindfleisch injizierten Aflatoxin B1 bei verschiedenen Lagerungszeiten
Zusammenfassung Bei –18° C zeigte sich bei 20, 25, 32, 153 und 183 Tagen gelagertem Rindfleisch eine Reduzierung in der Wiederfindungsrate von injiziertem Aflatoxin B1. Ein ungewöhnlicher Übergang des Aflatoxins in Äther- und Hexanverbindungen einer Silicium-Gel-Säule wurde festgestellt. Ätherfraktionen enthielten Aflatoxin B1-ähnliche Substanzen aus den gelagerten Rindfleischproben. Es wird eine wahrscheinliche Komplexverbindung des Aflatoxin B1 zu den Fleischbestandteilen diskutiert, die auf physikalisch-chemische Änderungen des Muskels während der Lagerung zurückgeführt werden.相似文献
193.
The Path to the Software-Defined Radio Receiver 总被引:3,自引:0,他引:3
After being the subject of speculation for many years, a software-defined radio receiver concept has emerged that is suitable for mobile handsets. A key step forward is the realization that in mobile handsets, it is enough to receive one channel with any bandwidth, situated in any band. Thus, the front-end can be tuned electronically. Taking a cue from a digital front-end, the receiver's flexible analog baseband samples the channel of interest at zero IF, and is followed by clock-programmable downsampling with embedded filtering. This gives a tunable selectivity that exceeds that of an RF prefilter, and a conversion rate that is low enough for A/D conversion at only milliwatts. The front-end consists of a wideband low noise amplifier and a mixer tunable by a wideband LO. A 90-nm CMOS prototype tunes 200 kHz to 20-MHz-wide channels located anywhere from 800 MHz to 6 GHz 相似文献
194.
Syed Sibte Raza Abidi Yong Han Chong Yan Zeng 《International Journal on Digital Libraries》2006,6(3):247-259
We present an information customization framework that leverages a hybrid of adaptive hypermedia and intelligent techniques,
in particular constraint satisfaction methods, to generate customized and factually consistent information based on a user profile. Information customization is
modeled as a constraint satisfaction problem, whereby a solution is derived by (a) satisfying user-model constraints to select
a user-specific set of ‘information snippets’; and (b) establishing inter-snippet consistency to ensure that all snippets
are compatible with each other. Our approach takes the unique step of establishing factually consistency – via the satisfaction
of inter-snippet constraints – between heterogeneous information snippets. A customized information package is generated by
systematically synthesizing the set of user-specific and factually consistent information snippets. The featured information
customization framework incorporates variations of various search and constraint satisfaction methods. The work is applied
in an E-Healthcare setting leading to the generation of customized healthcare information. 相似文献
195.
A. Abidi L. Kolsi M. N. Borjini H. Ben Aissia 《Numerical Heat Transfer, Part A: Applications》2013,63(9):785-809
This work presents a numerical study of the effect of the radiative heat transfer on the three-dimensional double diffusive convection in a differentially heated cubic cavity for different optical parameters of the medium. This numerical study is conducted for fixed Prandtl, Rayleigh, and Lewis numbers, Pr = 13.6, Ra = 105, Le = 2, and buoyancy ratio N in the range [–2, 0]. The natural convection equations, using the Boussinesq approximation for the treatment of buoyancy term in the momentum equation, are expressed using the vorticity–stream function formulation. These equations and the radiative transfer equation are discretized, respectively, with the control volume finite difference method and the FTn finite volume method. The influences of the optical thickness and the conduction–radiation parameter of the semitransparent fluid on heat and mass transfer are depicted. Results show different transitions of the structure of the main flow when varying the conduction–radiation parameter and the optical thickness. 相似文献
196.
Hybrid waterborne alkyd–acrylic dispersions with solid content of 40%, free from any surfactant and exempt of any organic solvent, were successfully synthesized by a melt co-condensation reaction between an acrylic prepolymer bearing carboxylic groups and a long-oil alkyd resin. Spontaneous emulsification of the ensuing hybrid resin was achieved by the addition of an aqueous ammonia solution that neutralized the carboxylic functions. The key role of the carboxylic groups on the stabilization process and on the storage stability of the dispersion was assessed and it was shown that the insertion of anhydride moieties within the acrylic prepolymer ensured the efficient coupling between the acrylic and the alkyd resin and prevented the phase separation. These dispersions are easy to implement and might be used to prepare high quality zero VOC coatings in terms of drying time, stability and gloss. The most stable dispersion was also used in the formulation of air-drying waterborne lacquers and their coating properties were evaluated. 相似文献
197.
Jimmin Chang Abidi A.A. Viswanathan C.R. 《Electron Devices, IEEE Transactions on》1994,41(11):1965-1971
Flicker noise is the dominant noise source in silicon MOSFET's. Even though considerable amount of work has been done in investigating the noise mechanism, controversy still exists as to the noise origin. In this paper, a systematic study of flicker noise in CMOS transistors from twelve different fabricators is reported under various bias conditions corresponding to the gate voltage changing from subthreshold to strong inversion, and the drain voltage changing from linear to saturation regions of operation. The measurement temperature was varied from room temperature down to 5 K. Experimental results consistently suggest that 1/f noise in n-channel devices is dominated by carrier-density fluctuation while in p-channel devices the noise is mainly due to mobility fluctuation 相似文献