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181.
Tadahiro Taniguchi Takayuki Nagai Tomoaki Nakamura Naoto Iwahashi Tetsuya Ogata Hideki Asoh 《Advanced Robotics》2016,30(11-12):706-728
Humans can learn a language through physical interaction with their environment and semiotic communication with other people. It is very important to obtain a computational understanding of how humans can form symbol systems and obtain semiotic skills through their autonomous mental development. Recently, many studies have been conducted regarding the construction of robotic systems and machine learning methods that can learn a language through embodied multimodal interaction with their environment and other systems. Understanding human?-social interactions and developing a robot that can smoothly communicate with human users in the long term require an understanding of the dynamics of symbol systems. The embodied cognition and social interaction of participants gradually alter a symbol system in a constructive manner. In this paper, we introduce a field of research called symbol emergence in robotics (SER). SER represents a constructive approach towards a symbol emergence system. The symbol emergence system is socially self-organized through both semiotic communications and physical interactions with autonomous cognitive developmental agents, i.e. humans and developmental robots. In this paper, specifically, we describe some state-of-art research topics concerning SER, such as multimodal categorization, word discovery, and double articulation analysis. They enable robots to discover words and their embodied meanings from raw sensory-motor information, including visual information, haptic information, auditory information, and acoustic speech signals, in a totally unsupervised manner. Finally, we suggest future directions for research in SER. 相似文献
182.
Ultra‐high‐resolution 1058‐ppi OLED displays with 2.78‐in size using CAAC‐IGZO FETs with tandem OLED device and single OLED device 下载免费PDF全文
Kohei Yokoyama Shinichi Hirasa Noriko Miyairi Yoshitaka Dozen Toshiki Sasaki Yasuhiro Jimbo Kouhei Toyotaka Makoto Kaneyasu Hiroyuki Miyake Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Masataka Nakada Takahiro Sato Naoto Goto 《Journal of the Society for Information Display》2016,24(3):159-167
We fabricated new 2.78‐in 1058‐ppi organic light‐emitting diode (OLED) displays. The displays used OLED devices with a tandem structure and a single structure and a field effect transistor (FET) using c‐axis aligned crystalline In–Ga–Zn–O (CAAC‐IGZO) for an active layer and employing the 1.5‐µm rule over a glass substrate. Even in the displays with such high resolution exceeding 1000 ppi, crosstalk that was observed in the lower luminance region was suppressed. The displays achieved high color reproducibility and reduced viewing angle dependence. 相似文献
183.
Long‐lived triplet excitons on organic molecules easily deactivate at room temperature because of the presence of thermally activated nonradiative pathways. This study demonstrates long‐lived phosphorescence at room temperature resulting from suppression of the nonradiative deactivation of triplet excitons in conventional organic semiconducting host–guest systems. The nonradiative deactivation pathway strongly depends on the triplet energy gap between the guest emitting molecules and the host matrices. The triplet energy gap required to confine the long‐lived triplet excitons (≈0.5 eV) is much larger than that of conventional host–guest systems for phosphorescent emitters. By effectively confining the triplet excitons, this study demonstrates long‐lived room‐temperature phosphorescence under optical and electrical excitation. 相似文献
184.
The R-curve behaviour of sintered silicon nitride was investigated by using short bar specimens. The samples were fabricated by sintering at 1700° C for 2 or 8 h in a nitrogen atmosphere, varying the initial contents of the silicon nitride powder. The R-curve was evaluated with a loading and unloading technique to calculateK
R during stable fracture. Steep R-curves were observed in the specimens made from the high initial content powder. Thus, the grainbridging effect behind the crack seems to contribute to the R-curve, because a steep R-curve corresponds to fibrous texture development. ApparentK
c values with an assumption of linear elastic fracture mechanics for the specimens undergoing 8h sintering, are greater than those undergoing 2 h sintering. These results can be attributed to microcracking. 相似文献
185.
Catalytic NH3 decomposition with limonite rich in α-FeOOH has been studied as a hot gas cleanup method to remove a low concentration of
NH3 from fuel gas produced in coal gasification. Fine particles of metallic Fe formed from α-FeOOH achieve the almost complete
decomposition of 2000 ppm NH3 to N2 at 500°C under a high space velocity of 45,000 h−1 and show the stable catalytic performance for 50 h. The predominant catalytic mechanism involving the formation and subsequent
decomposition of Fe nitrides may be proposed on the basis of the XRD and TPD results. 相似文献
186.
Ignacio E. dell'Erba Diana P. Fasce Roberto J. J. Williams Rosa Erra‐Balsells Yuko Fukuyama Hiroshi Nonami 《大分子材料与工程》2004,289(4):315-323
Summary: A new class of silsesquioxane (SSO), containing species with two to nine Si atoms bearing multiple intramolecular rings formed through Si? O? C bonds, was synthesized as a glassy powder. It was characterized by UV‐MALDI‐TOF MS, 29Si NMR and FT IR. Solutions containing different amounts of SSO in the diglycidyl ether of bisphenol A (DGEBA), were homopolymerized in the presence of (4‐dimethylamino)pyridine (DMAP) as initiator, leading to SSO‐modified epoxy networks. SSO species were covalently bonded to the epoxy network without any evidence of phase separation. The SSO addition provoked an increase in the elastic modulus in the glassy state explained by an increase in the cohesive energy density. The SSO addition gave also place to an increase in the intensity of tan δ and a decrease in both the glass transition temperature and the elastic modulus in the rubbery state. This was explained by a decrease in crosslink density associated with the flexibility of SSO structures. DMAP was much more effective than other usual initiators (like benzyldimethylamine, BDMA), in increasing the crosslink density of the resulting epoxy network. This led to high values of the glass transition temperature and the elastic modulus in the rubbery state.
187.
The structure of a new sterol isolated fromMusa sapientum has been shown by chemical and spectroscopic methods to be (24S)-14α,24-dimethyl-9α,19-cyclo-5α-cholest-25-en-3β-ol. In addition, several known (24S)-24-methyl-Δ25-sterols, their 24-methylene isomers and other sterols (4,4-dimethyl-, 4α-methyl- and 4-demethyl-sterols) together with 3-oxo-4α-methylsteroids
were isolated from the plant and identified. The biogenetic implication of these sterols and 3-oxosteroids is discussed. 相似文献
188.
The melt spinning of Pb-Bi-Ge alloys with Pyrex glass was investigated as a means of producing a superconducting long filament with highT
c. Continuous filaments with maximumT
c of more than 10 K of Pb100-x-y
Bi
x
Ge
y
(15x37 and 725) were obtained from the molten state at 1500 K with a winding speed of 0.95 m sec–1. The Pb49Bi33Ge18 filament, which was 34×10–6 m diameter and a ductile material with a tensile strength of 20 MPa and elongation of 2.7%, exhibited superconductivity at the highestT
c of 14.3 K. These filaments were found to be polycrystalline with a grain size of more than 5000×10–10 m and had a mixed structure of germanium (diamond) (h c p) and bismuth phases. The germanium element distributed homogeneously in the filament. 相似文献
189.
Tsumori K Nakano H Kisaki M Ikeda K Nagaoka K Osakabe M Takeiri Y Kaneko O Shibuya M Asano E Kondo T Sato M Komada S Sekiguchi H Kameyama N Fukuyama T Wada S Hatayama A 《The Review of scientific instruments》2012,83(2):02B116
We report on the characteristics of the electronegative plasma in a large-scale hydrogen negative ion (H(-)) source. The measurement has been made with a time-resolved Langmuir probe installed in the beam extraction region. The H(-) density is monitored with a cavity ring-down system to identify the electrons in the negative charges. The electron-saturation current decreases rapidly after starting to seed Cs, and ion-ion plasma is observed in the extraction region. The H(-) density steps down during the beam extraction and the electron density jumps up correspondingly. The time integral of the decreasing H(-) charge density agrees well with the electron charge collected with the probe. The agreement of the charges is interpreted to indicate that the H(-) density decreasing at the beam extraction is compensated by the electrons diffusing from the driver region. In the plasmas with very low electron density, the pre-sheath of the extraction field penetrates deeply inside the plasmas. That is because the shielding length in those plasmas is longer than that in the usual electron-ion plasmas, and furthermore the electrons are suppressed to diffuse to the extraction region due to the strong magnetic field. 相似文献
190.
Hoshino M Uesugi K Takeuchi A Suzuki Y Yagi N 《The Review of scientific instruments》2011,82(7):073706
An x-ray laminography system under an x-ray microscopic condition was developed to obtain a three-dimensional structure of laterally-extended planar objects which were difficult to observe by x-ray tomography. An x-ray laminography technique was introduced to an x-ray transmission microscope with zone plate optics. Three prototype sample holders were evaluated for x-ray imaging laminography. Layered copper grid sheets were imaged as a laminated sample. Diatomite powder on a silicon nitride membrane was measured to confirm the applicability of this method to non-planar micro-specimens placed on the membrane. The three-dimensional information of diatom shells on the membrane was obtained at a spatial resolution of sub-micron. Images of biological cells on the membrane were also obtained by using a Zernike phase contrast technique. 相似文献