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21.
Due to the recent proliferation of digital broadcasting systems, various schemes for broadcasting continuous media data such as music or movies have been studied. In general broadcasting systems, since clients have to wait until their desired data are broadcast, these schemes reduce the waiting time by dividing the data into several segments of equal size. However, continuous media data often have units for playing portions of the data. For example, data encoded by MPEG2 can be played every GOP (group of pictures). In this paper, we propose a scheme to reduce the waiting time considering the units. Our proposed scheme divides a continuous media data at every unit. By scheduling divided data so that clients finish receiving a unit before starting to play the unit, waiting time is effectively reduced.  相似文献   
22.
A generalized model, called the homotopy model, is presented to reconstruct surfaces from cross-sectional data of objects using a homotopy to generate surfaces connecting consecutive contours. The homotopy model consists of continuous toroidal graph representation and homotopic generation of surfaces from the representation. It is shown that the homotopy model includes triangulation as a special case and generates smooth parametric surfaces from contour-line definitions using homotopy. The model can be applied to contours represented by parametric curves as well as linear line segments. First, a heuristic method that finds the optimal path on the toroidal graph is presented. Then the toroidal graph is expanded to a continuous version. Finally, homotopy is used for reconstructing parametric surfaces from the toroidal graph representation. A loft surface is also a special case of homotopy, a straight-line homotopy. Homotopy that corresponds to the cardinal spline surface is also introduced. Three-dimensional surface reconstruction of human auditory surface reconstruction of human auditory ossicles illustrates the advantages of the homotopy model over the others.  相似文献   
23.
Nanowires consisting of regioregular poly(3-hexylthiophene) (P3HT) as a conducting polymer were prepared using p-xylene. Magnetic processing of the nanowires was carried out using two superconducting magnets with horizontal (Bmax = 8 T) and vertical (Bmax = 10 T) directions. The formation of the nanowires was confirmed by atomic force microscopy (AFM) measurement. The results from the AFM images and the polarized absorption spectra on glass plates indicated that the nanowires partly oriented themselves with their long axes, which are parallel to the π–π stacking direction, being perpendicular to the magnetic field. The magnetic orientation is most likely ascribed to anisotropy in the magnetic susceptibilities of the ordered P3HT in the nanowires.  相似文献   
24.
Polyacetal copolymers were prepared by cationic ring‐opening copolymerizations of 1,3,5‐trioxane (TOX) with 1,3‐dioxolane (DOX), and polyacetal terpolymers were prepared by terpolymerizations of TOX, DOX, and 2‐ethylhexyl glycidyl ether (EHGE). Polyacetal polymers with three different structures such as polyacetal homopolymers, polyacetal copolymers, and polyacetal terpolymers were compared in the mechanical properties and the creep characteristics, and discussed from the view point of the polymer structure. The polyacetal copolymers and the polyacetal terpolymers were determined by 1H‐MNR measurement. About 80 mol % of DOX and EHGE amounts in feed were incorporated randomly into the each polymer. From the plots of the degree of crystallinity (Xc) versus the tensile strength, the tensile strength and crystallintiy of the polyacetal homopoymers are higher than those of the polyacetal copolymers and the polyacetal terpolymers. However, the tensile strength does not decrease linearly with a decrease in the crystallinity among the polyacetal polymers with three different structures, the polyacetal homopolymer, the polyacetal copolymers, and the polyacetal terpolymers. Creep rupture was characterized by the activation volume, υc, value in Zhurkov's equation, which can be estimated from the slope in the plots of load versus log (rupture time) at 80°C. The polyacetal polymers with higher molecular weight have larger values of the activation volume than those with lower molecular weight. When the activation volume values are compared among the polyacetal polymers with the same molecular weights, they increase in the following order: the polyacetal homopolymers < the polyacetal copolymers < polyacetal terpolymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
25.
We found 11 genes (FAO1-11) encoding putative oxidoreductases in the Aspergillus oryzae genome, which are similar to fungal fructosyl-amino acid oxidases. The cDNAs corresponding to the genes were cloned and expressed in Escherichia coli. rFao2 had fructosyl-amino acid oxidase activity, whereas rFao1 did not show any enzyme activity, even though the deduced amino acid sequence of Fao1 is identical to that of one of the fructosyl-amino acid oxidase isozymes from Aspergillus oryzae. rFao7 and rFao8 showed oxidase activity toward sarcosine, L-pipecolate, and L-proline. rFao10 was active toward only sarcosine, of the substrates tested. The functions of the other proteins were also predicted from a phylogenetic analysis.  相似文献   
26.
In search of an efficient transdermal drug delivery system (TDDS), a polyhydroxyalkanoate (PHA)-based system with a polyamidoamine dendrimer was examined. Tamsulosin was used as the model drug. The dendrimer was found to act as the weak enhancer. By adding the dendrimer, the dendrimer-containing PHA matrix achieved the clinically required amount of tamsulosin permeating through the skin model. This is also the first report of the application of PHA and dendrimer to the TDDS.  相似文献   
27.
An axisymmetrical fiber-matrix cylindrical model with a circumferential crack in the matrix of finite diameter is formulated within elastostatic scope. The problem is considered by means of integral transforms and a singular integral equation with a dominant generalized Cauchy kernel is obtained. Following the numerical solution technique developed by Erdogan, Gupta and Cook, the singular integral equation is reduced to a system of linear equations. By solving the linear equations, stress intensity factors associated with the crack length and the material properties are calculated and discussed. The solutions presented in this study are found to be general, including the solutions as special cases of the present formulation for a homogeneous solid cylindrical bar and a thick-walled shell with an outer circumferential crack. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
28.
In expanding expressway networks in Japan, various types of structures have been constructed, e.g., long span bridges and bridges with high piers. The expressway structures are well designed for the external dynamic forces, e.g., earthquakes and strong winds. However, for further safety promotion of the expressway networks, it is important to evaluate the drivers’ responses under strong dynamic disturbances. The present authors have investigated the moving stability of a vehicle under seismic motion based on both numerical simulation and virtual experiments using a driving simulator. Strong crosswind is considered as another factor that makes it difficult for drivers to control their vehicles. This study investigates the moving stability of a vehicle under strong crosswind based on numerical analyses and driving simulator experiments. To predict the future position of a moving vehicle including the reaction of a driver, the second-order predictable correction model is used in the numerical analyses. The results obtained from the numerical and experimental studies are compared and the validity of the driver model is discussed. It is expected that this research is helpful for the decision-making of expressway closure under strong wind and the design of wind barriers.  相似文献   
29.
Due to the recent popularization of mobile multimedia broadcasting, broadcasting continuous media data such as audio and video has attracted great deal of attention. In general continuous media data broadcasting, since clients have to wait to receive data before playing it, various schemes to reduce waiting time have been studied. Some reduce the waiting time by dividing the data into several segments and broadcasting preceding segments frequently with a single channel. However, by dividing the data into numerous segments and producing an effective broadcast schedule, the waiting time can be further reduced. In this paper, we propose a scheduling protocol to reduce waiting time with large-scale data segmentation.  相似文献   
30.
It is necessary to use renewable energy, such as photovoltaic, wind power, and biomass energy, from the viewpoint of CO2 regulation and environmental protection of the Earth. In recent years, the tendency is toward larger wind power generation systems to achieve cheaper electricity. Generators having capacities of 1500 kW to 2000 kW tend to dominate the market. However, a large wind power generation system has limitations in terms of location and can be installed only in the suburbs. At the same time, a city‐type compact wind power generation system, designed for city needs, has more flexibility and can be installed in the residential areas of a city. In this paper, we introduce an original control operation system called a “pump‐up” operation system, designed to effectively use the city wind, and report the results of its field test. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 56–63, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20440  相似文献   
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