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61.
62.
The objective of this research is to use current linked open data (LOD) to generate questions automatically to support history learning. This paper tries to clarify the potential of LOD as a learning resource. By linking LOD to natural language documents, we created an open learning space where learners have access to machine understandable natural language information about many topics. The learning environment supports learners with content-dependent questions. In this paper, we describe the question generation method that creates natural language questions using LOD. The integrated data is combined to a history domain ontology and a history dependent question ontology to generate content-dependent questions. To prove whether the generated questions have a potential to support learning, a human expert conducted an evaluation comparing our automatically generated questions with questions generated manually. The results of the evaluation showed that the generated questions could cover more than 80% of the questions supporting knowledge acquisition generated by humans. In addition, we confirmed the automatically generated questions have a potential to reinforce learners’ deep historical understanding. 相似文献
63.
Keiji Hayashi Tomoki Shiraishi Kazuho Toyoda Fumiya Tanaka Taiga Mori Takumi Hata 《Computer Physics Communications》2011,(9):2032-2035
Laws of dynamic nano-friction (i.e., continuous wearless friction) were searched for under steady spatial distributions of the local quasi-temperature, by molecular dynamics (MD) simulations. The temperature control of the non-conservative model was carried out by extending the isothermal MD method using the Nosé–Poincaré thermostat. The results suggested that the threshold phenomenon characterizes sliding-velocity dependence of the nano-frictional force between crystal lattices constituting a nano-electromechanical system (NEMS). This phenomenon was turned out to be a universal feature, whether heat transfer to the environment exists or not. 相似文献
64.
Eiji Hayashi 《Artificial Life and Robotics》2008,12(1-2):346-352
Autonomous and mobile robots are being expected to provide various services in human living environments. However, many problems
remain to be solved in the development of autonomous robots that can work like humans. When a robot moves, it is important
that it be able to have self-localization abilities and recognize obstacles. For a human, the present location can be correctly
checked through a comparison between memorized information assuming, it is correct, and the present situation. In addition,
the distance to an object and the perception of its size can be estimated by a sense of distance based on memory or experience.
Therefore, the environment for robotic activity assumed in this study was a finite-space such as a family room, an office,
or a hospital room. Because an accurate estimation of position is important to the success of a robot, we have developed a
navigation system with self-localization ability which uses only a CCD camera that can detect whether the robot is moving
accurately in a room or corridor. This article describes how this system has been implemented and tested with our developed
robot. 相似文献
65.
66.
Kazuyuki Maeshima Nanao Hayashi Tadayuki Murakami Fumiki Takahashi Hisashi Komae 《Journal of chemical ecology》1985,11(1):1-9
Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds. 相似文献
67.
Adsorption isotherms of pigments from alkali-refined vegetable oils with clay minerals 总被引:1,自引:0,他引:1
Keito Boki Moriaki Kubo Naohito Kawasaki Hidehito Mori 《Journal of the American Oil Chemists' Society》1992,69(4):372-378
Adsorption isotherms of pigments from alkali-refined oils (rapeseed, soybean, wheatgerm, safflower, corn, cottonseed and sunflower)
were measured to investigate the applicability of the Langmuir and Freundlich equations and to elucidate the adsorption characteristics
of pigments on sepiolites and standard activated clay. The Freundlich equation was more applicable to the experimental adsorption
isotherms. The equilibrium amount adsorbed, acidity, pore size distribution and inflection of the Freundlich isotherms could
be explained by assuming that pigments were adsorbed on the stronger acid sites in smaller pores at low concentration, and
then in the larger ones when the concentration increased. The amount adsorbed increased with a rise in adsorption temperatures
from 70 to 110°C, and the heat of adsorption was below 10 kcal/mol. The results indicate that pigments were physically adsorbed
on the acid sites activated at higher adsorption temperatures. 相似文献
68.
Chemical and Chromatic Bases for Preferential Visiting By the Cabbage Butterfly, Pieris rapae, to Rape Flowers 总被引:1,自引:2,他引:1
Scent and coloration of corolla were examined as floral attributes responsible for preferential visiting by the cabbage butterfly, Pieris rapae, to rape flower, Brassica rapa. Floral volatile components that release the flower-visiting behavior of the butterfly were identified by chemical analyses, electroantennography (EAG), and two behavioral bioassays: proboscis extension reflex (PER) in response to odor and attraction to artificial flowers. GC and GC-MS analyses of the headspace volatiles from the flowers revealed the presence of six aromatic compounds, benzaldehyde, phenylacetaldehyde, benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole in decreasing order of quantity. Of these, phenylacetaldehyde elicited the highest response in the PER assay. While benzyl alcohol, 2-phenylethanol, benzaldehyde, and phenylacetonitrile evoked moderate responses, the PER-eliciting activity of indole was very weak. In two-choice behavioral bioassays, artificial flowers scented with any one of these PER-active compounds attracted significantly more butterflies than control (unscented) flowers, whereas those treated with indole were almost inactive. The EAG activities of the six chemicals were not high and were about the same at a low dose (1 g), but phenylacetaldehyde elicited a much stronger response from both sexes at higher doses (10 and 100 g). An overall profile of EAG responses at a dose of 100 g was analogous to that of PER performance, suggesting that floral volatiles may be involved in close-range location or recognition of flowers rather than long-range attraction. By spectroscopic and UV-photographic examinations of rape flower, the central part of the corolla was found to absorb UV rays in marked contrast to the other parts, which reflected near-UV rays (max = 350 nm). This indicates that the flower is endowed with a conspicuous nectar guide that is probably an important visual stimulus for attracting foraging adults of P. rapae. Consequently, the present findings strongly suggest that this elaborate pollination strategy of rape flower, characterized by its good combination of olfactory and visual attractiveness, accounts for preferential visiting by the cabbage butterfly to the flower. 相似文献
69.
Y. Ogata S. Uchiyama M. Hayashi M. Yasuda F. Hine 《Journal of Applied Electrochemistry》1990,20(4):555-558
The pH on the surface of an ion-exchange membrane was measured with a microprobe in a laboratory scale chlor-alkali cell to study the leakage of OH– through the membrane. The solution pH in the vicinity of the membrane facing the anode was found to be considerably higher than that in the bulk solution because of penetration and leakage of OH–. The pH varied with the membrane type. This explains why the carboxylate membrane is not protonated and can be used as a separator in chlor-alkali cells.Deceased. 相似文献
70.
The size distribution of gold nanoparticles was estimated based on the scattering intensity data obtained from small angle X-ray scattering (SAXS) and compared with the result of micrographs by transmission electron microscopy. The slope of the Guinier plot was used to estimate the mean size assuming a narrow particle size distribution. When the size distribution is narrow, the mean size can be easily obtained from slope of a Guinier plot of scattering data within 10% error. Additionally, assuming a lognormal size distribution, the size distribution and the mean size can be calculated using the experimental SAXS data in the fitting analysis. The histogram method, which utilizes the coefficient matrix of scattering intensity, was also applied to the estimation of the size distribution, and this method could be useful for a rough estimate of the size distribution. 相似文献