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61.
Masanori Kakimoto Kaoru Matsuoka Tomoyuki Nishita Takeshi Naemura Hiroshi Harashima 《Computer Graphics Forum》2005,24(2):185-193
This paper proposes a novel and general method of glare generation based on wave optics. A glare image is regarded as a result of Fraunhofer diffraction, which is equivalent to a 2D Fourier transform of the image of given apertures or obstacles. In conventional methods, the shapes of glare images are categorized according to their source apertures, such as pupils and eyelashes and their basic shapes (e.g. halos, coronas, or radial streaks) are manually generated as templates, mainly based on statistical observation. Realistic variations of these basic shapes often depend on the use of random numbers. Our proposed method computes glare images fully automatically from aperture images and can be applied universally to all kinds of apertures, including camera diaphragms. It can handle dynamic changes in the position of the aperture relative to the light source, which enables subtle movement or rotation of glare streaks. Spectra can also be simulated in the glare, since the intensity of diffraction depends on the wavelength of light. The resulting glare image is superimposed onto a given computer‐generated image containing high‐intensity light sources or reflections, aligning the center of the glare image to the high‐intensity areas. Our method is implemented as a multipass rendering software. By precomputing the dynamic glare image set and putting it into texture memory, the software runs at an interactive rate. 相似文献
62.
Daisuke Nagamatsu Masanori Maeda Keisuke Hashimoto Kenji Okumoto Hiroshi Kageyama Yasuhiko Shirota 《Journal of the Society for Information Display》2005,13(5):399-404
Abstract— A novel emitting vinyl polymer, poly[4‐(7‐{4‐[N,N‐bis(9,9‐dimethylfluoren‐2‐yl)amino]phenyl}‐2,1,3‐benzothiadiazol‐4‐yl)phenylethylene] (PVFABT), was designed and synthesized. The new vinyl polymer was found to form smooth amorphous films with a high glass‐transition temperature of 199°C. The polymer possesses bipolar character with both electron‐donating and accepting properties. It undergoes reversible anodic oxidation and cathodic reduction to give stable cation and anion radicals. It exhibits intense orange fluorescence in solution and as film. A multilayer organic electroluminescent device using PVFABT as an emitting material emitted orange light, exhibiting high performance. 相似文献
63.
Masanori Takaya Ken Ito Gosuke Ohashi Yoshifumi Shimodaira 《Journal of the Society for Information Display》2005,13(8):685-690
Abstract— A color‐conversion method for a light‐emitting multi‐primary‐color display is proposed. While amulti‐primary‐color display uses four or more primary colors to reproduce a wide color gamut, multiple sets of primary‐color signals are needed to reproduce one color. Therefore, linear programming, which results in low power consumption, was adopted to uniquely determine the set of primary‐color signals. Although a highly accurate color conversion was achieved by using linear programming with low power consumption, it requires a very long time to convert colors of high‐resolution images. Therefore, by categorizing the color conversion of linear programming as a classification problem, colors are converted by using the decision‐tree method, which is a classification method. As a result, color conversion with high accuracy, low power consumption, and short conversion time was achieved. 相似文献
64.
Two new types of control method have been developed based on model predictive control for stable-target tracking of a nonholonomic
mobile robot. One method (Method 1) is a new nonlinear control method. This was developed based on model predictive control
(predictive nonlinear control) to predict the next position of a mobile robot using the current velocities of the right and
left wheels. This technique uses a tuning guideline in predictive nonlinear control. The other method (Method 2) is a combination
of Method 1 and proportional control (predictive proportional nonlinear control). Method 2 involves a tuning guideline not
only in a predictive nonlinear controller, but also in a proportional controller. In this technique, the selection of a tuning
guideline in the proportional controller is enhanced, and thereby increases the control action in closed-loop responses. In
Method 1, the nonlinear controller is derived from Liapunov stability theory, and is used to control the linear and angular
velocities for locomotion control. Tuning parameters in the nonlinear controller (in Method 1) are selected to satisfy various
design criteria, such as stability, performance, and robustness. Method 1 has certain limitations that result in a decrease
of the performance criteria specified. Strong nonlinearities in the mobile robot system result in accumulated errors. To enhance
performance further, we developed Method 2 as the solution for decreasing cumulative errors. Hence, the proportional controller
is added to Method 1 in the closed-loop form in order to eliminate errors. The advantage of Method 2 is that it can cope with
strong nonlinearities in the mobile vehicle system. The results of the performances of Method 1 and Method 2 are shown to
demonstrate the effectiveness of both methods, and also the better performance of Method 2. The two new methods are effective
in stable-target tracking, yielding an increase in performance and stability. 相似文献
65.
This article deals with the development of learning methods for an intelligent control system for an autonomous mobile robot.
On the basis of visual servoing, an approach to learning the skill of tracking colored guidelines is proposed. This approach
utilizes a robust and adaptive image processing method to acquire features of the colored guidelines and convert them into
the controller input. The supervised learning procedure and the neural network controller are discussed. The method of obtaining
the learning data and training the neural network are described. Experimental results are presented at the end of the article.
This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January
15–17, 2001 相似文献
66.
The idea of a flow diode has been proposed to improve the pump coastdown characteristics of the internal recirculation pumps adopted by the ABWR. In this paper, the transient behavior from forced to natural circulation was experimentally investigated by simulating a pump coastdown condition for the purpose of providing an available source of information that is necessary for designing the flow diode. The results of the study showed that the transient behavior after pump coastdown was influenced by the coastdown period, the trigger velocity and the initial driving force of natural circulation. The potential of each driving factor was governed by the delay time for boiling, which is a very important parameter in natural circulation of boiling two-phase flow. In consequence, a guide for the designing of a flow diode was proposed. 相似文献
67.
This paper considers a standby-redundant system consisting of 2 systems, in which one is main and the other is its standby-redundant system. These systems also consist of 2 subsystems connected in series, in which each one is composed of several identical units connected in parallel.A feature of this system is that the system has 2 switching devices connecting subsystems, in addition to one connecting main and standby systems, in order to utilize surviving units as many as possible. In this consideration it is assumed that all the units are not repairable.We shall obtain the system reliability and the mean time to system failure, and examine numerically the effects of this model to the usual one without particular switching devices. 相似文献
68.
69.
Kusumoto M Suzuki R Nishiya Y Okitsu T Oka M 《Journal of Bioscience and Bioengineering》2004,97(6):406-411
IS1203v is an insertion sequence (IS) which is identical to the most abundant IS elements in the genome of Escherichia coli O157:H7. However, there is no sequence homologous to IS1203v in the genome of E. coli K-12. We constructed a system to analyze the excision frequency of IS1203v, and demonstrated that the frequency in E. coli O157:H7 was approximately 10(5) times higher than that in E. coli K-12. We also investigated the excision frequencies of IS1203v in various E. coli isolates, and showed that the excision frequencies of IS1203v-possessing strains were approximately 10(3) times higher than those of IS1203v-nonpossessing strains. The results suggest that the IS1203v-possessing strains use a common system to enhance IS1203v excision. 相似文献
70.
The polarization characteristics of a terahertz (THz) wave transmitted through two-dimensional (2-D) metallic photonic crystals (MPCs) are investigated. The 2-D MPCs studied in this paper are metal slabs perforated periodically with circular holes. We measured the polarization characteristics of the THz wave using a THz time-domain spectroscopic system with wire grid polarizers in the time and frequency domains. The linearly polarized incident THz wave changes its polarization direction and becomes elliptic after it transmits through the sample. This phenomenon is highly sensitive to the incident angle. It is shown that the frequency range at which the polarization rotation occurs is related to the lattice constant of a photonic crystal, indicating the importance of photonic band modes of the 2-D MPC in the mechanism of the phenomenon. 相似文献