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1.
Autonomous control of vehicles has recently attracted considerable attention. In this sense, vehicle merging has become an important topic in this field of research. However, in conventional studies, the controlled vehicle must calculate the movement of other surrounding vehicles to complete the merge, requiring high computational costs. In this paper, we focus on dragonfly behavior to solve this issue. Indeed, insects can behave adaptively in the complex real world in spite of the limited size of their brains. They reduce the computational requirements of their brain by relying on different properties of their surroundings, basing their intelligent behaviors on simple strategies. The behavior of a dragonfly when chasing a prey is an example of these strategies. In this study, we address the vehicle merging maneuver by applying dragonfly’s strategies to control the movement of the merging vehicle. We propose a simple control method inspired by the aforementioned strategies and, finally, we present simulation results that were conducted to demonstrate the effectiveness of this method. 相似文献
2.
This paper describes a localization system for a swimming robot to survey underwater narrow environments. In that environment, external sensors cannot be set up to localize the robot position, as there are many structures and the robot moves three-dimensionally. Therefore, the position needs to be calculated only by internal sensors. In this work, a new localization method based on map-matching is proposed, referring to cross-sectional shape data cut from a three-dimensional computer-aided design (CAD) data as an environmental map and structural shapes measured by a range sensor. As a range sensor, an ultrasonic sensor which is two-dimensional scanning-type was developed. The reflected signals of the ultrasonic sensor have some noise. Only structural shape data are extracted from the reflected signals. The image correlation is used as the matching method. Experiments to evaluate the performance of the proposed system were implemented at a mock-up environment. As a result, it was confirmed that the position was detected with an accuracy of 100 mm. The error is mainly caused by measurement error of the ultrasonic sensor that is used to calculate structural shapes. We concluded to improve the measurement accuracy of the ultrasonic sensor to reduce localization error. 相似文献
3.
Computational Visual Media - Quantitatively evaluating the psychological and perceptual effects of objects is an important issue, but is difficult. In cognitive studies, the psychological potential... 相似文献
4.
Koshi Takenaka Miku Sato Masaya Mitamura Yasunori Yokoyama Naoyuki Katayama Yoshihiko Okamoto 《Journal of the American Ceramic Society》2020,103(4):2757-2763
We used spray-dry method to synthesize fine powder of β-Cu1.8Zn0.2V2O7 showing large negative thermal expansion (NTE) linearly to temperature over a wide temperature range. The NTE of β-Cu1.8Zn0.2V2O7 is produced by microstructures consisting of voids and anisotropic thermal deformation of crystal grains in ceramics. By reducing the size of the microstructures that produce NTE, large NTE equivalent to that of bulk was realized, even for ceramic particles of about 2 μm size. Comparison with particles produced using a conventional method demonstrates that the particle size distribution is narrow and that the particles are nearly spherical. This achievement is expected to pave the way to use of NTE materials in micrometer-scale control of thermal expansion. 相似文献
5.
Shogo Mamada Naoyuki Yaguchi Masanori Hansaka Masafumi Yamato Hirohisa Yoshida 《应用聚合物科学杂志》2015,132(15)
This study was addressed to the influence of an electric field strength applied at fabrication process and matrix properties, such as the dielectric constant and the Young's modulus, on “pseudo‐1‐3 piezoelectric ceramic/polymer composite” in order to further enhance the piezoelectricity of that. The pseudo‐1‐3 piezoelectric ceramic/polymer composite consists of linearly ordered piezoelectric ceramic particles in polymer material. Silicone gel, silicone rubber, urethane rubber, and poly‐methyl‐methacrylate, which exhibit different dielectric constants and Young's modulus, were used as matrices to evaluate the matrix influence. The piezoelectricity of the pseudo‐1‐3 piezoelectric ceramic/polymer composite was evaluated using the piezoelectric strain constant d33. The d33 is one of the indices of the piezoelectric properties for piezoelectric materials. As a result, it was confirmed that d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite increased with the increase of the electric filed strength applied at fabrication process, though, it reached a constant value at a certain strength value. Further it was confirmed that dielectric constant of the matrix had a small influence on d33 of the pseudo‐1‐3 piezoelectric ceramic/polymer composite, however, in case of matrix of lower Young's modulus, d33 was increase. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41817. 相似文献
6.
The fluoride adsorption onto the hydroxide flocs of Al(III), Fe(III), or a mixture of the two was studied. The optimum pH was influenced by the flocs’ solubility and surface charge. Although the Al(III) hydroxide flocs had a maximum adsorption capacity at the equilibrium concentration of 8 mg-F/L, the two-stage adsorption process revealed that the mixture of the Al(III) and Fe(III) hydroxide flocs required the smallest adsorbent dose as the concentration changed from 40 to 8 mg-F/L. Thus, the simultaneous dosing of Al(III) and Fe(III) combined with a two-stage adsorption process appears to be an effective option for fluoride removal. 相似文献
7.
A series of ozone/UV treatment under injection of ozone with different ozone-gas bubble sizes was performed at pH 1.7 and 7.4. The increase in the bubble size and the decrease in pH enhanced the ozone utilization efficiency. The enhancement of ozone utilization efficiency was caused by the shift of the production pathway of hydroxyl radical (OH) from the OH production via O3 – to the UV photolysis of H2O2. The lower pH caused this shift through the chemical equilibrium of H2O2 and HO2 –, and the large bubbles caused this shift through the augmentation of H2O2 transport from the bubble surface to the bulk solution. 相似文献
8.
Fumiya ShirakiTaeko Yoshikawa Akihiro Oshima Yuji OshimaYuya Takasawa Naoyuki FukutakeTomoko Gowa Oyama Tatsuya UrakawaHajime Fujita Tomohiro TakahashiToshitaka Oka Hisaaki KudoTakeshi Murakami Yoshimasa HamaMasakazu Washio 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(15):1777-1781
The graded energy deposition of heavy ion beam irradiation to polymeric materials was utilized to synthesize a novel proton exchange membrane (PEM) with the graded density of sulfonic acid groups toward the thickness direction. Stacked Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were irradiated by Xe54+ ion beam with the energy of 6 MeV/u under a vacuum condition. The induced trapped radicals by the irradiation were measured by electron spin resonance (ESR) spectroscopy. Irradiated films were grafted with styrene monomer and then sulfonated. X-ray photo-electron spectroscopy (XPS) spectra showed that the densities of sulfonic acid groups were controlled for injection “Surface” and transmit “Back” sides of the fabricated PEM. The membrane electrode assembly (MEA) fabricated by the function-graded PEM showed improved fuel cell performance in terms of voltage stability. It was expected that the function-graded PEM could control the graded concentration of sulfonic acid groups in PEM. 相似文献
9.
A sparse mask that persists beyond the duration of a target can reduce its visibility, a phenomenon called object substitution masking. Y. Jiang and M. M. Chun (2001a) found an asymmetric pattern of substitution masking such that a mask on the peripheral side of the target caused stronger substitution masking than on the central side. Assuming spatial attention was focused toward the target, the peripheral and central masks were located in the same and opposite direction of an attentional path with reference to the target in their study. We hypothesized that this asymmetric mask configuration relative to the attentional shift contributes to asymmetric substitution masking. To test this hypothesis, we conducted four experiments among which the presence or absence of the center–periphery relationship and the presence or absence of the asymmetric mask configuration were manipulated independently and orthogonally. The results suggest that asymmetric substitution masking occurs relative to the direction of spatial attention irrespective of the central–peripheral relation. We propose that the asymmetry in substitution masking might be explained by attentional momentum associated with orienting toward the target. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Kazuya Ogawa Naoyuki Makiuchi Yoshiaki Kobuke 《International journal of molecular sciences》2013,14(1):322-331
A conjugated-bisimidazolylporphyrin bridged by bis(ethynylfluorene) was synthesized and organized into linear polymer through self-coordination having mean molecular weights, Mw and Mn, of ~2.1 × 105 Da and ~1.6 × 105 Da, respectively. A large two-photon absorption cross section value of 3.4 × 105 GM (per dimer unit) was observed. This value was comparable to that of the previously reported self-assembled linear polymer consisting of butadiyne-bridged imidazolylporphyrins. The two-photon absorption properties could be controlled by tuning the wavelength and absorption intensity of the one-photon absorption. 相似文献