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991.
Generalized Stochastic Sampling Method for Visualization and Investigation of Implicit Surfaces 总被引:2,自引:0,他引:2
Satoshi Tanaka Akihiro Shibata Hiroaki Yamamoto & Hisakiyo Kotsuru 《Computer Graphics Forum》2001,20(3):359-367
Recently we proposed the stochastic sampling method (SSM), which can numerically generate sample points on complicated implicit surfaces quickly and uniformly. In this paper we generalize the method in two aspects: (1) We introduce two kinds of boundary conditions, so that we can sample a finite part of an open surface spreading infinitely. (2) We generalize the stochastic differential equation used in the SSM, so that its solutions can satisfy plural constraint conditions simultaneously. The first generalization enables us to visualize cut views of open surfaces. The second generalization enables us to visualize intersections of static and moving implicit surfaces, which leads to detailed investigation of intersections and other interesting applications such as visualization of contour maps. 相似文献
992.
We describe a low-loss 25-GHz-spaced multi/demultiplexer with more than 1000 channels that covers the S-, C-, and L-bands of optical fiber amplifiers. It was achieved by cascading a 2.5-THz-spaced arrayed-waveguide grating (AWG) with Gaussian passbands as a primary filter and ten 25-GHz-spaced 1×200 AWGs as secondary filters in a tandem configuration 相似文献
993.
We examined the effects of mu-opioid receptor agonist and antagonists, and kappa-opioid receptor agonist on the hypoxia/hypoglycemia-induced reduction in 2-deoxyglucose uptake of rat hippocampal slices. Naloxone, a mu-opioid receptor antagonist and (5,7,8)-(+)-3,4-dichloro-N-methyl-N-(7,8,1-pyrrolidinyl)-1-oxaspirol+ ++ (4,5)dec-8-yl)-benzeneacetamide methanesulfonate, U-62,066E, a kappa-opioid receptor receptor agonist, showed neuroprotective actions against the hypoxia/hypoglycemia-induced deficit in glucose uptake. In contrast, morphine exhibited an exacerbating action. These results suggest that blockade of mu-opioid receptor- and stimulation of kappa-opioid receptor-mediated functions has a protective role against the hypoxia/hypoglycemia-induced decreases in glucose metabolism in hippocampal slices. Chronic administration of morphine (10 mg/kg) for 9 days affected neither the basal nor the hypoxia/hypoglycemia-induced reduction in 2-deoxyglucose uptake. Rats treated with morphine chronically exhibited not only tolerance to the analgesic effect but also tolerance to the exacerbating action. However, chronic morphine did not modify U-62,066E-induced neuroprotection. These findings indicate that the receptor mechanisms of neuroprotection produced by the activation of kappa-opioid receptors may not be involved in mu-opioid receptor function. 相似文献
994.
Digital AVR application to power plants 总被引:1,自引:0,他引:1
Hirayama K. Tone Y. Takagi K. Murakami H. Shibata M. Nagamura H. Takagi Y. 《Energy Conversion, IEEE Transaction on》1993,8(4):602-609
The digital AVR is not simply a digital version of the analog AVR, but can realize sophisticated control functions that were difficult to achieve with analog circuits, thus making it possible to enhance the stability of power system by PSS (power system stabilizers). This paper describes the test results of digital AVRs applied to power plants, their system configuration and functions, as well as the outline of an auto-tuning PSS (or AT-PSS) planned to be incorporated in digital AVRs in the future 相似文献
995.
In rats of various ages (11 weeks to 24 months), restricted feeding was carried for 6 successive days and food was withheld completely on the 7th day to assess the effect of aging on food anticipatory activity. When feeding was restricted to a single meal at a fixed time of day (1330-1730), rats exhibited intense locomotor activity from 1-3 h before feeding time (prefeeding activity). This prefeeding activity was still detected on the fasting day. In addition, intense locomotor activity was observed for 1330-1730 even on the fasting day (mealtime-associated activity). Thus, mealtime-associated activity of the fasting day became an another good index for food anticipatory activity. These results indicate that the rats had come to anticipate the mealtime. Both prefeeding and mealtime-associated activities were similar at 11 weeks and 9 months of age, but they were impaired at 12 and 24 months of age. In 11-week-old rats, there was a negative correlation between the level of mealtime-associated activity and the daily duration of access to food, but this relationship was absent in 12-month-old rats. The present study suggests that aging strongly impairs the manifestation of food anticipatory activity in rats. 相似文献
996.
997.
T Furukawa K Kumai T Kubota S Hirahata H Shimizu H Matsui T Takahara K Aizawa S Shibata A Shimada 《Canadian Metallurgical Quarterly》1993,23(4):298-306
The effectiveness of the intraperitoneal administration of cis-diamminedichloroplatinum (II) (DDP) on peritoneal carcinomatosis caused by gastric cancers was evaluated. Seventeen patients were treated with one of three protocols, consisting of the intraperitoneal injection (ip) of DDP at doses of 70 and 110 mg/m2, with or without sodium thiosulfate (STS) rescue. The area under the curve (AUC) of DDP for sufficient anticancer activities against cultured human cell lines in vitro was estimated at 240 micrograms h/ml, which was equivalent to the AUC gained by 110 mg/m2 ip DDP in the clinical studies. The cytotoxic activity of DDP was reduced by approximately 50% with 100-fold STS in the AUC in the experimental studies. However, this was achieved only in urine, and not in either the peritoneal cavity or in plasma in the clinical studies. Three cases of a partial response against peritoneal carcinomatosis were seen from a total of four evaluable cases treated with 110 mg/m2 DDP, and no renal toxicities were observed in those treated with the STS rescue. The results of this study led us to conclude that high-dose ip DDP treatment combined with the STS rescue would be useful chemotherapy against peritoneal carcinomatosis caused by gastric cancers. 相似文献
998.
Saida T. Takiguchi K. Kuwahara S. Kisaka Y. Miyamoto Y. Hashizume Y. Shibata T. Okamoto K. 《Photonics Technology Letters, IEEE》2002,14(4):507-509
In this letter, we fabricated an integrated polarization-mode dispersion compensator on a silica-based planar lightwave circuit that incorporated an endless polarization controller and a fixed polarization dependent delay line. The compensator consisted of polarization beam splitters, thermooptic phase shifters, tunable couplers, and polarization converters. We experimentally confirmed its operation at a data rate of 43 Gb/s 相似文献
999.
The theory and the applications of artificial neural networks, especially in a control field, are described. Recurrent networks and feedforward networks are discussed. Application to pattern recognition, information processing, design, planning, diagnosis, and control are examined. Hybrid systems using the neural networks, fuzzy sets, and artificial intelligence (AI) technologies are surveyed 相似文献
1000.
Fukuda T. Shibata T. Tokita M. Mitsuoka T. 《Industrial Electronics, IEEE Transactions on》1992,39(6):497-503
A structure for a neural network-based robotic motion controller is presented. Simulations of both position and force servos are carried out, and the approach is shown to be useful for a nonlinear system in an uncertain environment. The neural network comprises a four-layer network, including input/output layers and two hidden layers. Time delay elements are included in the first hidden layer, so that the neural network can learn dynamics of the system. The authors also implement a new learning method based on fuzzy logic, which is useful to accelerate learning and improve convergence 相似文献