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51.
Naoyuki Kubota Yusuke Nojima Fumio Kojima Toshio Fukuda 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2006,10(10):891-901
The purpose of this study is to develop partner robots that can obtain and accumulate human-friendly behaviors. To achieve this purpose, the entire architecture of the robot is designed, based on a concept of structured learning which emphasizes the importance of interactive learning of several modules through interaction with its environment. This paper deals with a trajectory planning method for generating hand-to-hand behaviors of a partner robot by using multiple fuzzy state-value functions, a self-organizing map, and an interactive genetic algorithm. A trajectory for the behavior is generated by an interactive genetic algorithm using human evaluation. In order to reduce human load, human evaluation is estimated by using the fuzzy state-value function. Furthermore, to cope with various situations, a self-organizing map is used for clustering a given task dependent on a human hand position. And then, a fuzzy state-value function is assigned to each output unit of the self-organizing map. The robot can easily obtain and accumulate human-friendly trajectories using a fuzzy state-value function and a knowledge database corresponding to the unit selected in the self-organizing map. Finally, multiple fuzzy state-value functions can estimate a human evaluation model for the hand-to-hand behaviors. Several experimental results show the effectiveness of the proposed method. 相似文献
52.
Okamura T Takeno T Dohi M Yasumasa I Hayashi T Toyoda M Noda H Fukuda S Horie N Ohsugi M 《Journal of Bioscience and Bioengineering》2000,89(5):474-478
With thrombosis a major cause of death in Japan and the Western world, thrombin-inhibitory agents that constrain the formation of fibrin are sought. We screened for basidiomycetes showing anti-thrombin activity and isolated Laetiporus sulphureus. However, it was difficult to cultivate and its form was not satisfactory. We therefore used protoplast fusion between L. sulphureus and the commonly cultivated basidiomycete Hypsizygus marmoreaus to obtain cultivable basidiomycetes that produced an anti-thrombin substance. For the protoplast fusion of L. sulphureus and H. marmoreaus, the protoplast concentration, alternating electric field intensity, dielectrophoresis duration, and field pulse intensity used were of 1 x 10(7) protoplasts/ml, 100 V/cm.1 MHz, 60 s, and 8 kV/cm, respectively. The number of regenerated colonies obtained was 4961, from which 43 strains were selected for electrophoretic analysis. Four of the fusants were found to have a band from each parent in isozyme patterns obtained using their crude extract. The fruiting bodies of the fusants were very similar to those of H. marmoreaus. Crude extract from each of the fusants and from L. sulphureus showed anti-coagulative activity in terms of the thrombin clotting time. We thus obtained improved basidiomycetes that produce an anti-thrombin substance, are easily cultivated, and whose form resembles H. marmoreaus, a commonly used culinary mushroom. 相似文献
53.
Sekiguchi K. Seki Y. Okitani N. Fukuda M. Critchley S. Habib W.G. Hartman D. Shaw K. 《Industry Applications, IEEE Transactions on》1996,32(3):608-616
The new coupled pickle line and cold mill (CPCM) has been processing steel since December 1991 at Dofasco Inc. in Hamilton, Ontario, Canada. This mill rolls both sheet and tin plate. The work rolls for the last stand are often textured by grit blasting to roll “matte” finished strip. A new computer-targeted control system was developed for the roll speeds and gaps, specifically for matte rolling. The new set-up system uses Stone's model, which is more appropriate for the limited reductions evident with the rougher rolls. Conventional automatic gauge control (AGC) systems using thickness measurements after the last stand are limited in performance by the effect of long transport delays. These limitations are particularly critical during mill acceleration and deceleration. The use of a thickness gauge before the stand with matte rolls allows the development of AGC systems using shorter control loops for final gauge control. The AGC system uses a Smith predictor for transport lag, (phase shift), and compensation. The combination of the shorter AGC loop and the Smith predictor allows higher gains to be used in the control system. This set-up and control system has contributed to Dofasco's position as a market leader in thickness performance 相似文献
54.
T. Okano J. Tanabe M. Fukuda M. Tanaka 《Journal of the American Oil Chemists' Society》1992,69(1):44-46
The surface-active properties and emulsification ability of sodium α-sulfonated fatty acid esters, CmH2m+1CH-(SO3Na)COOCnH2n+1, were studied as a function of the hydrophobic alkyl chainlength in the fatty acid (m=8−16) and the alcohol (n=8−18). As
a result, it was discovered that sodium α-sulfonated fatty acid esters have a structural effect on the Krafft point different
from that of amphiphiles with short alkyl chains. Moreover, some of the α-sulfonated fatty acid esters have quite low interfacial
tensions, as well as non-foaming properties, which depend upon the total (m+n) number of carbon atoms in the alkyl chains. 相似文献
55.
56.
Kakui M. Kato T. Kashiwada T. Nakazato K. Fukuda C. Onishi M. Nishimura M. 《Electronics letters》1995,31(1):51-52
Based on system optimisation through theoretical model simulations, 2.4 Gbit/s repeaterless transmission over 306 km nondispersion-shifted fibre has been demonstrated with no power penalty, using a directly modulated DFB laser with a bulk active layer and dispersion-compensating fibres 相似文献
57.
It is experimentally demonstrated that the increase in residual spectral linewidth during device degradation is due to an increase in 1/f noise in a multiple quantum-well (MQW) distributed-feedback (DFB) laser. The origin of 1/f noise and its influence on device characteristics is discussed and clarified by observing the degradation behavior of the spectral linewidth 相似文献
58.
CONTEXT: Physical activity and fitness are believed to reduce premature mortality, but whether genetic factors modify this effect is not known. OBJECTIVE: To investigate leisure physical activity and mortality with respect to familial aggregation of health habits during childhood and factors that may enable some individuals to achieve higher levels of fitness. DESIGN: Prospective twin cohort study. SETTING: Finland. SUBJECTS: In 1975, at baseline, 7925 healthy men and 7977 healthy women of the Finnish Twin Cohort aged 25 to 64 years who responded to a questionnaire on physical activity habits and known predictors of mortality. Those who reported exercising at least 6 times per month with an intensity corresponding to at least vigorous walking for a mean duration of 30 minutes were classified as conditioning exercisers, those who reported no leisure physical activity were classified as sedentary, and other subjects were classified as occasional exercisers. MAIN OUTCOME MEASURES: All-cause mortality and discordant deaths among same-sex twin pairs from 1977 through 1994. RESULTS: Among the entire cohort, 1253 subjects died. The hazard ratio for death adjusted for age and sex was 0.71 (95% confidence interval [CI], 0.62-0.81) in occasional exercisers and 0.57 (95% CI, 0.45-0.74) in conditioning exercisers, compared with those who were sedentary (Pfor trend <.001). Among the twin pairs who were healthy at baseline and discordant for death (n=434), the odds ratio for death was 0.66 (95% CI, 0.46-0.94) in occasional exercisers and 0.44 (95% CI, 0.23-0.83) in conditioning exercisers compared with those who were sedentary (P for trend, .005). The beneficial effect of physical activity remained after controlling for other predictors of mortality. CONCLUSION: Leisure-time physical activity is associated with reduced mortality, even after genetic and other familial factors are taken into account. 相似文献
59.
The modal and relative intensity noise of InGaAsP/InP lasers are monitored before and after degradation. These noise levels under VHF modulation are scarely affected by laser degradation and are almost determined by VHF modulation, although the noise levels under DC bias increase after degradation. 相似文献
60.