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71.
Most of the emerging content-based multimedia technologies are based on efficient methods to solve machine early vision tasks. Among other tasks, object segmentation is perhaps the most important problem in single image processing. The solution of this problem is the key technology of the development of the majority of leading-edge interactive video communication technology and telepresence systems. The aim of this paper is to present a robust framework for real-time object segmentation and tracking in video sequences taken simultaneously from different perspectives. The other contribution of the paper is to present a new dedicated parallel hardware architecture. Its composed of a mixture of Digital Signal Processing (DSP) and Field Programmable Gate Array (FPGA) technologies and uses the Content Addressable Memory (CAM) as a main processing unit. Experimental results indicate that small amount of hardware can deliver real-time performance and high accuracy. This is an improvement over previous systems, where execution time of the second-order using a greater amount of hardware has been proposed.Mahmoud Meribout (BS85, M91). Received the PhD degree in Electronic Engineering from the University of Technology of Compiegne (France), in January 3rd 1995. He worked one year as an Associate Researcher, where he has been involved in some industrial projects related to hardware board design and video processing. FromNovember 1995 to October 2000, he has beenworking in Japan, with NTT and NEC corporations respectively, where he has been involved in several projects related to hardware & software design of next generation multimedia and networking equipments. He is holding several Japanese and American patents related to this particular topic. In 1998, he has received the NTT best award for his research and development records.Maamouru Nakanishi received the B.S. and M.S. in Electronics in 1985 and 1987 respectively, all from Kyoto University. Since 1987, he has been engaged in R&D of parallel processing architectures, memory-processor integration technology at NTT Corporation (Tokyo, Japan), when he has been involved in research on Advanced Content Addressable Memory applied to video processing. In 1998, he has received the NTT best award for his research and development records. 相似文献
72.
Pressureless sintering of SiC was accomplished at 2100°C with oxide additives. These additives were the products of the reaction of Al(OH)3 with HCl and of Y(OH)3 with HCOOH. These reaction products were dissolved in water and mixed with submicrometer β-SiC. A mixture of equal weights of these additives was effective for the sintering of SiC. 相似文献
73.
The effects of gas composition, pressure and substrate temperature on the properties of relatively thick (0.2–0.8 μm) SnO2 films deposited onto fused quartz substrates by r.f. magnetron sputtering are reported. The lowest resistivity of about 2 × 10?3ωcm was attained for high rate deposition conditions of about on substrates at a temperature of 400°C in an atmosphere of 10% O2. This value corresponds to a carrier density of 3 × 1020cm?3 and a mobility of 10 cm2V?1s?1. The crystal structure was found to be sensitive to all the above parameters. Low resistivity films showed a highly preferred orientation of (101) parallel to the substrate. 相似文献
74.
Mamoru Ai 《Journal of Catalysis》1975,40(3):327-333
The vapor-phase oxidation of 1-butene, butadiene, and acetic acid, the isomerization of 1-butene, and the dehydration and dehydrogenation of isopropyl alcohol (IPA) were carried out, in the presence of an excess of air, over two series of catalysts, SnO2MoO3, and SnO2P2O5, and the relationship between the catalytic behavior and the acid-base properties of the catalysts was investigated. The acidity and the basicity of the SnO2MoO3 catalysts were measured by studying the adsorption of basic and acidic molecules, respectively, in the gas phase, using both the static and pulse methods. The acidities of the SnO2MoO3 catalysts are dramatically high at the Mo content of 30–60 atom%, though those of the SnO2-rich (Mo < 20 atom%) and MoO3-rich (Mo > 80 atom%) catalysts are fairly low. The basicity is remarkably enhanced by the introduction of a small amount of MoO3 (Mo < 5 atom%). It can be said that the catalysts are basic in the MoO3-poor composition. In the case of the SnO2P2O5 catalysts, the acidity and basicity were evaluated from the catalytic activity for the dehydration of IPA to propylene and the (dehydrogenation rate for IPA)/(dehydration rate for IPA) ratio, respectively. The introduction of P2O5 increases the acidity and decreases the basicity, to a very small extent, so it cannot cause a remarkable modification in the catalytic behavior; that is, the SnO2P2O5 catalysts are rather basic. 相似文献
75.
Interaction of tocored with unsaturated fatty esters 总被引:1,自引:0,他引:1
Tocored, an oxidation product of tocopherol and its model, 2,2,7,8-tetramethyl-5,6-chromanquinone reacted with methyl linoleate
at an elevated temperature to form an adduct with isomerized linoleate. Oxidation of tocored in fatty esters produced a variety
of products, depending on the degree of unsaturation of the esters. With methyl palmitate no addition product was detected
but tocopurple and tocoreddimer were identified as minor products irrespective of the degree of saturation. A mechanism involving
the interaction of tocored with lipid radicals to yield an adduct as the consequence of antioxidative action of tocored is
postulated. 相似文献
76.
In order to study the two-phase natural circulation and flow termination during a small break loss of coolant accident in LWR, a hot leg U-bend simulation loop has been built based on the two-phase flow scaling criteria developed under this program. The nitrogen-water system has been used to isolate the key hydrodynamic phenomena from heat transfer problems. Various tests were carried out to establish the basic mechanism of the flow termination and reestablishment as well as to obtain essential information on scale effects of various parameters such as the loop frictional resistance, thermal center, U-bend curvature, and inlet geometry. It was found that the permanent termination of the natural circulation was related to the head balance between the hot and cold legs. The local flow condition at the inverted U-bend could produce intermittent flow, however was not related to the permanent flow termination. The void distribution in a hot leg, flow regime, and natural circulation rate have been measured in detail for various conditions. Significant effects of the inlet geometry on these were observed. Near the flow termination condition, large amplitude flow oscillations occurred. The occurrence of this type of flow instability is important for safety analyses, because it may lead to loop-to-loop oscillations or flow excursions in a prototype system which has a multi-loop configuration. 相似文献
77.
Lefteri H. Tsoukalas Mamoru Ishii Ye Mi 《Engineering Applications of Artificial Intelligence》1997,10(6):545-555
A neurofuzzy methodology for flow identification based on signals obtained from an impedance void meter is presented. The methodology combines the filtering and interpolative capabilities of neural networks with the representational advantages of fuzzy systems for the purpose of mapping idiosyncratic area-averaged impedance measurements to multiphase flow regimes. It has been shown that electrical signals representing the conductance of the intervening medium can be used to infer crucial flow parameters, and that area-averaged signals contain sufficient information about flow regime and the structure of its two-phase constituents. The neurofuzzy approach is a promising means for reconstructing the visual imagery of flow in a process, analogous to tomography, and holds considerable promise for multiphase flow diagnostic and measurement applications in the nuclear as well as in the petroleum, biomedical, and food-processing industries. 相似文献
78.
Interfacial area concentration measurement is quite important in gas-liquid two-phase flow. To determine the accuracy of measurement of the interfacial area using electrical resistivity probes, numerical simulations of a passing bubble through sensors are carried out. The two-sensors method, the four-sensors method and the correlative method are tested and the effects of sensor spacing, bubble diameter and hitting angle of the bubbles on the accuracy of each measurement method are investigated. The results indicated that the two-sensors method is insensitive to the ratio between sensor spacing and bubble diameter, and hitting angle. It overestimates the interfacial area for small hitting angles while it gives a reasonable accuracy for smaller bubbles and large hitting angles. The four-sensors method gives accurate interfacial area measurements particularly for the larger bubble diameters and smaller hitting angles, while for smaller bubbles and larger hitting angles, the escape probability of bubbles through the sensors becomes large and the accuracy becomes worse. The correlative method gives an overall accuracy for interfacial area measurement. Particularly, it gives accurate measurements for larger bubbles and larger hitting angles while for smaller hitting angles, the spatial dependence of the correlation functions affects the accuracy. 相似文献
79.
Toshio Tanaka Shigeki Suzuki Yoshitsugu Nekomoto Mamoru Tanaka 《Nuclear Engineering and Design》1994,147(3)
This paper deals with a diagnostic and monitoring system for assessing the integrity of pipe branches, during the operation of the nuclear power plant. This system have been developed under the concept of “easy to use without any sophisticated analysis” and “portable”. The accuracy of the diagnosis is based on the model optimization subsystem, which automatically modifies the numerical vibration model so as to fit its natural frequency to the actual natural frequency. The information obtained by this system may be reflected to a maintenance program of the plant to assure more reliable operation of the plant. 相似文献
80.
Mamoru Ishida Takeo Uehara Toshio Arai Hideki Takeda Tadashi Yamaguchi Takeshi Taniguchi Tetsuya Katsumi Masayuki Kobayashi Hitoshi Ofune 《Intermetallics》2002,10(11-12)
The performance of MU/SC conversion sleeve produced by bulk metallic glass (Zr55Al10Ni5Cu30) was examined. A precision die-casting method was applied to improve size accuracy. The size accuracy of the conversion sleeve produced by the precision die-casting method was ±1 μm, and optical insertion loss (Li) was less than 0.3 dB for a standard value. The wear resistance of metallic glass is improved by surface oxidation treatment in air at 673 K. The MU/SC conversion sleeve produced from bulk metallic glass has superior characteristics for optical parts. 相似文献