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71.
Takuma Yamaguchi Minoru Maruyama Hidetoshi Miyao Yasuaki Nakano 《International Journal on Document Analysis and Recognition》2005,7(2-3):168-177
This paper proposes a method to recognize digits in a natural scene, such as telephone numbers on a signboard. Candidate regions of digits are extracted from an image through contrast enhancement, edge extraction, and labeling. Since the target text patterns are in a 3D space, unlike traditional character recognition problems, we have to deal with the image transformation effect due to the orientation in the 3D space and projection. We have to cancel the effect as much as possible before digit recognition. In our method, the image transformation effect is modeled as skew and slant. In the proposed method, simplified Hough transform is used for the skew normalization. After the skew normalization, the remaining effect of image transformation is corrected by circumscribing digit patterns with tilted rectangles and affine transformation. In experiments, we tested a total of 1,332 images of signboards with 11,939 digits. We obtained a digit extraction rate of 99.2% and a correct digit recognition rate of 98.8%.Received: 15 December 2003, Accepted: 21 October 2004, Published online: 2 February 2005 相似文献
72.
We planned to develop a small and inexpensive measurement device for determination of molecular concentration. The analysis process operates by superimposing a rotating electric field on a magnetic field. When the strength and frequency of the rotating electric field and the mass and speed of the ion are predetermined, the circular radius of the ion's trajectory is fixed. We designed a computer program to simulate ion movement in the electric field and magnetic field. It is possible to calculate the circular movement of the ion in the rotating electric field, and then calculate the circular movement in the superimposed state of the rotating electric field and magnetic field. The magnitude of the mass spectrometer conventionally determines resolution ability. Our definition of resolution is the fraction equal to the distance of separation divided by the distance of the attainment point. The resolution increases gradually at first, and then rises suddenly and dramatically to over 20 times the resolution of that of a spectrometer which does not use a superimposed field. We believe that the theory of ion movement in the rotating electric field and magnetic field could lead to the development of a small and inexpensive analysis machine. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(1): 15–26, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10113 相似文献
73.
74.
The freezing point depression, ΔT, of swollen DCP-, TT- and sulphur-cured natural rubber in benzene was observed. The dependence of the parameter, aH, introduced by Kuhn, was not affected by the type of structure of crosslink sites. It was found from the comparison of the experimental results and scaling law that aH can reflect not only the difference in three-dimensional structure of network between a degraded and an undegraded rubber vulcanizates but also the difference in degraded network structures between rubber samples with various conditions of degradation. 相似文献
75.
The objective of this research is to develop a product modeling system to support mechanism design from the beginning of the design. The system must cope with two aspects of the design process which are top-down design and preliminary design. The current capabilities of existing CAD and CAE systems are not sufficient to support these two aspects. In this research a modeling method with an abstract model and an incompletely defined model is proposed. The mechanism is presented by constraints and depault values because constraints are suitable for representing the abstract model for a mechanism and default values are useful to supplement an incompletely defined model. We also introduce module-based modeling with mechanism modules corresponding directly to the functionalities of the mechanism and show that it is suitable for top-down design. Incomplete constraints are solved with default values so that the shape and location of the incompletely defined model can be modified and the motion of the model can be simulated. Finally, we illustrate the mechanism modeling system with some examples. 相似文献
76.
The cytochemical staining characteristics of basic nuclear proteins during gametogenesis in both sexes of the free-living nematode Panagrellus silusiae were monitored by absorption microspectrophotometry. During spermatogenesis, the levels of both of the nuclear-bound Sakaguchi and 1-fluoro-2, 4-dinitrobenzene (FDNB) reagents per Feulgen-DNA content increase prior to meiosis and subsequently drop off during spermiogenesis. During oogenesis, the amount of Sakaguchi-protein to DNA ratio rises slightly whereas the FDNB-protein to DNA ratio undergoes a meagre decline. Since the oocyte of Panagrellus accumulates DNA in excess of a 4C DNA equivalent, the relative constancy of the ratio of basic nuclear protein content to DNA amount during oogenesis signifies that these proteins are being continously produced during oocyte maturation. After treatment with alkaline fast green (pH 8.1) the cytoplasmic and nuclear regions of the gonocytes of both sexes yield such an intense reaction that microspectrophotometric measurements could not be taken. The basis of the cytoplasmic staining reaction to the fast green (pH 8.1) dye was not determined. The rapid, highly deterministic programme of embryogenesis in Panagrellus may require a substantial stockpiling of basic nuclear proteins during oogenesis. 相似文献
77.
78.
Goto H. Nagase Y. Takada T. Tahara A. Momma Y. 《Electron Devices, IEEE Transactions on》1991,38(8):1840-1844
A report is presented of the results of an investigation of device parameters and collector-to-emitter breakdown voltages of double polysilicon self-aligned transistors with highly doped collectors using a two-dimensional process/device simulation system. Favourable phosphorous-ion implanting condition for a highly doped pedestal collector was found to achieve a high cutoff frequency as well as low AC base resistance and small base-collector capacitance, thereby keeping the minimum collector-to-emitter breakdown voltage of 3 V. The authors also report ECL circuit performance improvements achieved in experiments that realized a minimum ECL gate delay time of 26.3 ps/gate at switching current of 1.64 mA as a result of process optimization. Moreover, a 1/8 static frequency divider T-F/F has been observed to operate up to a maximum frequency of 15.8 GHz 相似文献
79.
80.
A Tahara M Saito T Sugimoto Y Tomura K Wada T Kusayama J Tsukada N Ishii T Yatsu W Uchida A Tanaka 《Canadian Metallurgical Quarterly》1998,125(7):1463-1470
Three subtypes of human (h) arginine vasopressin (AVP) receptors, hV1A, hV1B and hV2, were stably expressed in Chinese hamster ovary (CHO) cells and characterized by [3H]-AVP binding studies. In addition, the coupling of the expressed receptor protein to a variety of signal transduction pathways was investigated. Scatchard analysis of saturation isotherms for the specific binding of [3H]-AVP to membranes, prepared from CHO cells transfected with hV1A, hV1B and hV2 receptors, yielded an apparent equilibrium dissociation constant (Kd) of 0.39, 0.25 and 1.21 nM and a maximum receptor density (Bmax) of 1580 fmol mg(-1) protein, 5230 fmol mg(-1) protein and 7020 fmol mg(-1) protein, respectively. Hill coefficients did not differ significantly from unity, suggesting binding to homogenous, non-interacting receptor populations. Pharmacological characterization of the transfected human AVP receptors was undertaken by measuring the relative ability of nonpeptide AVP receptor antagonists, YM087, OPC-21268, OPC-31260, SR 49059 and SR 121463A, to inhibit binding of [3H]-AVP. At hV1A receptors, the relative order of potency was SR49059>YM087>OPC-31260>SR 121463A> >OPC-21268 and at hV2 receptors, YM087=SR 121463A>OPC-31260>SR 49059> >OPC-21268. In contrast, the relative order of potency, at hV1B receptors, was SR 49059> >SR 121463A=YM087=OPC-31260=OPC-21268. In CHO cells expressing either hV1A or hV1B receptors, AVP caused a concentration-dependent increase in intracellular Ca2+ concentration ([Ca2+]i) with an EC50 value of 1.13 nM and 0.90 nM, respectively. In contrast, stimulation of CHO cells expressing hV2 receptors resulted in an accumulation of cyclic AMP with an EC50 value of 2.22 nM. The potency order of antagonists in inhibiting AVP-induced [Ca2+]i or cyclic AMP response was similar to that observed in radioligand binding assays. In conclusion, we have characterized the pharmacology of human cloned V1A, V1B and V2 receptors and used these to determine the affinity, selectivity and potency of nonpeptide AVP receptor antagonists. Thus they may prove to be a valuable tool in further examination of the physiological and pathophysiological roles of AVP. 相似文献