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81.
Tabu search for attribute reduction in rough set theory   总被引:2,自引:0,他引:2  
In this paper, we consider a memory-based heuristic of tabu search to solve the attribute reduction problem in rough set theory. The proposed method, called tabu search attribute reduction (TSAR), is a high-level TS with long-term memory. Therefore, TSAR invokes diversification and intensification search schemes besides the TS neighborhood search methodology. TSAR shows promising and competitive performance compared with some other CI tools in terms of solution qualities. Moreover, TSAR shows a superior performance in saving the computational costs.  相似文献   
82.
The authors have been working on natural language understanding based on the knowledge representation language L md and its application to robot manipulation by verbal suggestion. The most remarkable feature of L md is its capability of formalizing spatiotemporal events in good correspondence with human/robotic sensations and actions, which can lead to integrated computation of sensory, motory and conceptual information. This paper describes briefly the process from text to robot action via semantic representation in L md and the experimental results of robot manipulation driven by verbal suggestion. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
83.
The double-inlet pulse tube refrigerator that has a diaphragm inserted in a bypass-tube, which enabled it to transmit a pressure oscillation whereas to obstruct a DC gas flow, was manufactured and tested. The oscillating flow behavior inside of the refrigerator was studied by using a smoke-wire flow visualization technique. It was found that if the diaphragm was optimized, the performance would be improved more than that of the refrigerator with a bypass valve due to the increase in the PV work of the gas and the decrease in the convective heat loss caused by a secondary flow.  相似文献   
84.
Poly lactic acid (PLA) has attracted a lot of attention in recent years because of its good properties such as high transparency, high tensile strength and excellent biodegradability. However, high modulus and low strain are its shortage, making it unfeasible to be applied as packaging materials. To overcome this limitation, in this study, PLA is mixed with ethylene vinyl acetate (EVA). The morphological, thermal and mechanical properties of the enzymatically degraded PLA/EVA blends were fully investigated under agricultural soil of Red River Delta, Vietnam. It was demonstrated that some new strains were responsible for the biodegradation of PLA/EVA. To best of our knowledge, these strains were not reported in the literature up to now.  相似文献   
85.
Cu nanoparticle ink was prepared from Cu nanoparticles that were coated with a gelatin layer at an average diameter of 46 nm. The Cu nanoparticle ink was applied on the polyimide substrate. Conductive films were fabricated using the Cu nanoparticle ink with a two-step annealing process consisting of oxidative pre-heating at 200 °C under 10 ppm O2-N2 mixed gas flow and reductive calcination at 250 °C under 3 vol.% H2-N2 mixed gas flow showed a low resistivity of 5 μΩ cm. The hydrolysis of the remaining gelatin layer by H2O vapor, which was formed during the reduction of the Cu oxide by 3 vol.% H2-N2 mixed gas, was suggested. The results suggest the possibility of the removal of the gelatin layer without oxidative pre-heating and simultaneous sintering of Cu nanoparticles in reductive calcination.  相似文献   
86.
This article describes a multimodal command language for home robot users, and a robot system which interprets users’ messages in the language through microphones, visual and tactile sensors, and control buttons. The command language comprises a set of grammar rules, a lexicon, and nonverbal events detected in hand gestures, readings of tactile sensors attached to the robots, and buttons on the controllers in the users’ hands. Prototype humanoid systems which immediately execute commands in the language are also presented, along with preliminary experiments of faceto-face interactions and teleoperations. Subjects unfamiliar with the language were able to command humanoids and complete their tasks with brief documents at hand, given a short demonstration beforehand. The command understanding system operating on PCs responded to multimodal commands without significant delay. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
87.
Shigeo Kuroda 《Polymer》2011,52(9):1869-1873
A new reactive and functionalized polystyrene with a maleimide moiety at the one polymer end was synthesized with N-(4-(1-chloroethyl)pheyl)maleimide (CEPMI)/SnCl4/tetra-butylammonium chloride (TBAC) initiating system. The polymer obtained with the CEPMI/SnCl4/TBAC initiating system under the condition of [TBAC]/[SnCl4] = 1 was to be maleimide-type macromonomer with polystyrene having controlled molecular weight of polystyrene (VI). VI could be polymerized with anionic and radical initiators to give new type graft polymer (poly[N-(4-ethylphenyl)maleimide]-graft-polystyrene) with controlled chain length with respect to side chains.  相似文献   
88.
This article considers the success rates in a multimodal command language for home robot users. In the command language, the user specifies action types and action parameter values to direct robots in multiple modes such as speech, touch, and gesture. The success rates of commands in the language can be estimated by user evaluations in several ways. This article presents some user evaluation methods, as well as results from recent studies on command success rates. The results show that the language enables users without much training to command home robots at success rates as high as 88%–100%. It is also shown that multimodal commands combining speech and button-press actions included fewer words and were significantly more successful than single-modal spoken commands.  相似文献   
89.
We developed a low cost, user-friendly multimedia delivery system, to provide medical lectures saved as multimedia contents to persons engaged in medicine. This system was created using the RealSystem package with the TCP/IP network. Users can review lectures and medical meeting presentations with video and audio through the Internet, whenever convenient. Each medical source of video and slide has been clearly displayed on a screen. Members of medical associations or medical students can easily review the most interesting parts of these files. This system is being used efficiently in distance learning and aids the diffusion of the latest information and technology to busy physicians and medical students.  相似文献   
90.
Surface relief associated with martensitic transformation—tetragonal-to-monoclinic phase transformation—that occurred during isothermal aging at temperatures of 400 and 473 K was observed via atomic force microscopy, using prepolished and thermally etched surfaces of zirconia–3 mol% yttria that was sintered at a temperature of 1923 K for 5 h. The isothermal martensitic transformation occurred first at grain boundaries and advanced into grain interiors as the aging time increased and then spread successively into the surrounding grains. The transformation area, which had an approximately round shape, increased as the aging time increased. The fine structure of the surface relief was composed of many tent shapes that were several nanometers high with an angle of ∼165°.  相似文献   
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