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991.
A high-speed three-dimensional (3-D) image sensor for a 1000 range maps/s 3-D measurement system based on a light-section method is presented. It employs a row-parallel search architecture to achieve a high-speed frame access rate for the detection of activated pixels on the focal plane. The row-parallel search operation is carried out using chained search circuits embedded in a pixel. Moreover, we propose a row-parallel address acquisition technique using a bit-streamed column address flow. Row-parallel processors receive the bit-streamed column address and calculate the center position of activated pixels. The pipelined operations enable a multisampling technique that improves the resolution of pixel detection. A 375 /spl times/ 365 3-D image sensor using the present architecture has been designed in a one-poly five-metal 0.18-/spl mu/m standard CMOS process and successfully tested. It attains a frame access rate of 394.5 kHz with four samplings, which corresponds to 1052 range maps/s. The multisampling operation improves the sub-pixel resolution to around 0.2 pixels and achieves a range accuracy of less than 1.10 mm at a target distance of 600 mm. 相似文献
992.
Yuji Toda Syunsuke Ikeda Kentaro Kumagai Takeshi Asano 《Canadian Metallurgical Quarterly》2005,131(11):950-960
Field observations were performed to determine the effects of flood flow on the geometrical and chemical characteristics of flood plain soil and the distribution of riparian vegetation in a gravel river. The results of the observations show a decrease in the amounts of the particulate nutrients in the flood plain soil during fairly large flood, because the fine sands that serve as a nutrient source were removed by the flood flow. Numerical simulations for the transport of suspended sediments were performed by varying the peak discharge of the flood, and the change of the particulate nutrients in flood plain soil was estimated by using the results of the simulations. The numerical analysis predicts the reduction of the particulate nutrients in the flood plain soils well. The particulate nutrients on the flood plains decrease if the discharge exceeds the flood of approximately 2 year return period in the observation area. 相似文献
993.
Certain olid organic dye, which had been thermally evaporated on a substrate such as glass, were found to change physically as well as chemically by light irradiation and thermal treatment. This paper deal with the mechani m of such phenomena. The analytical results suggest dimer formation by light irradiation and lactone formation upon heating. An imaging system can be designed utilizing the above phenomena which give a positive from a negative image. 相似文献
994.
When two lights of different wavelengths are dichoptically presented to the eyes to form a single visual field, the fusion of colors cannot be assured unless the difference is relatively small. The limit of the wavelength difference delta lambda beyond which no homogeneous color is obtained was determined for the wavelengths covering a range of about 500 to 660 nm. It varied from about 10 to 50 nm depending upon the wavelength region investigated, which is much larger than the delta lambda values normally obtained in wavelength discrimination experiments. The limit was also obtained for a pair made up of a white light and a colored light that varied in purity. The value was again quite large. These results suggested that the tolerance for color difference is fairly lenient as far as binocular color fusion is concerned. 相似文献
995.
996.
BACKGROUND: Propofol and fentanyl infusion rates should be varied according to the patient's responsiveness to stimulation to maintain satisfactory anesthetic and operative conditions. However, somatic and autonomic responses to various noxious stimuli have not been investigated systematically for intravenous propofol and fentanyl anesthesia. METHODS: Propofol and fentanyl were administered via computer-assisted continuous infusion to provide stable concentrations and to allow equilibration between plasma-blood and effect-site concentrations. The propofol concentrations needed to suppress eye opening to verbal command and motor responses after 50-Hz electric tetanic stimulation, laryngoscopy, tracheal intubation, and skin incision in 50% or 95% of patients (Cp50 and Cp95) were determined at fentanyl concentrations of 0.0, 1.0, 2.0, 3.0, and 4.0 ng/ml in 133 patients undergoing lower abdominal surgery. The ability of propofol with fentanyl to suppress hemodynamic reactions in response to various noxious stimuli also was evaluated by measuring arterial blood pressure and heart rate before and after stimulation. RESULTS: The various Cp50 values for propofol alone (no fentanyl) for the various stimuli increased in the following order: Cp50loss of consciousness, 4.4 microg/ml (range, 3.8-5.0); Cp50tetanus, 9.3 microg/ml (range, 8.3-10.4); Cp50laryngoscopy, 9.8 microg/ml (range, 8.9-10.8); Cp50skin incision, 10.0 microg/ml (range, 8.1-12.2); and Cp50intubation, 17.4 microg/ml (range, 15.1-20.1; 95% confidence interval). The reduction of Cp50loss of consciousness, with fentanyl was minimal; 11% at 1 ng/ml of fentanyl and 17% at 3 ng/ml of fentanyl. A plasma fentanyl concentration of 1 ng/ml (3 ng/ml) resulted in a 31-34% (50-55%) reduction of the propofol Cp50s for tetanus, laryngoscopy, intubation, and skin incision. Propofol alone depresses prestimulation blood pressure but had no influence on the magnitude blood pressure or heart rate increase to stimulation. Propofol used with fentanyl attenuated the systolic blood pressure increases to various noxious stimuli in a dose-dependent fashion. CONCLUSIONS: The authors successfully defined the propofol concentration required for various stimuli. Tracheal intubation was the strongest stimulus. The absence of somatic reactions for propofol does not guarantee hemodynamic stability without fentanyl. Propofol with fentanyl was able to suppress motor and hemodynamic reactions to various noxious stimuli. 相似文献
997.
BACKGROUND AND METHODS: To elucidate the effect of hyperglycemia on disaccharidase activities, the specific and total activities of the disaccharidases were measured in the intestinal mucosa and kidney cortex of diabetic and hyperglycemic rats. The diabetes was induced with an intraperitoneal injection of streptozotocin (60 mg/kg). The rats were made hyperglycemic with an intravenous instillation of a solution containing 40% dextrose monohydrate at a rate of 1.5 ml/h for 24 h. RESULTS: The blood glucose level was 387+/-45 mg/dl and 382+/-35 mg/dl (mean +/- standard deviation) in diabetic and hyperglycemic rats, respectively. In diabetic rats the intestinal maltase, sucrase, and lactase activities were significantly higher than those in control rats. Similarly, disaccharidase activities in hyperglycemic rats were significantly higher than those in control rats. The renal maltase activity in diabetic rats was significantly lower than that in control rats. The maltase activity in hyperglycemic rats, however, was not significantly different from that in control rats. CONCLUSIONS: These results suggest that 1) hyperglycemia directly increases the activities of intestinal maltase, sucrase, and lactase; 2) hyperglycemia does not influence renal maltase activity; and 3) hyperglycemia is partly responsible for increased activities of intestinal disaccharidases in diabetes mellitus. 相似文献
998.
999.
Synthesis of Cs–aluminosilicate zeolites and thermal phase transformation from BIK to CAS frameworks
The hydrothermal synthesis of zeolite from a gel containing Cs to some alkali cations is thoroughly investigated, and a new route for the synthesis of CAS-type zeolite is found by the thermal treatment of BIK-type zeolite, which was prepared by the conventional synthesis method from aluminosilicate gel containing cesium and additional alkali metal ions. The effect of the alkali cations on the phase transformation of BIK into CAS at 900 °C is also investigated. It is found that lithium cations play an important role in the transformation and that the time required for the transformation into CAS decreases with the lithium content in the starting mixture. The required time for the transformation in potassium-containing BIK is more than that in lithium-containing BIK. The mechanism of structural transformation is considered. 相似文献
1000.
Effects of oleic acid or triolein on lymphatic recovery of docosahexaenoic acid (DHA) given as an ethyl ester were examined
in rats with cannulated thoracic ducts. Lymphatic recovery of ethyl DHA given with oleic acid or triolein was significantly
higher than in rats given ethyl DHA alone. DHA distrbuted almost exclusively at the 1-and 3-position of triglyceride in lymph
collected at 0–3 h after the administration, when it was given with oleic acid or triolein. A small part of DHA distributed
at the 2-position when ethyl DHA was the sole fatty acid given. Oleic acid given as free acid or triolein with ethyl DHA was
a major fatty acid at the 2-position. Intramolecular distribution of DHA and oleic acid in lymph triglyceride was similar
when ethyl DHA was given with oleic acid or triolein. 相似文献