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141.
142.
Side-chain type liquid crystalline polyacetylene, which has mesogenic moieties as side chains, is one of the promising materials for practical applications in the electronics. Micropatterning of the conductive polymer is a significant issue in this field. We show a simple method to fabricate micropatterns of side-chain type liquid crystalline polyacetylene derivative. Under dry condition, stripes patterns and lattice pattern were formed based on the fingering instability and stick-slip motion of the receding meniscus. Honeycomb-patterned polymer film was obtained by casting polymer solution under humid condition. The micropatterns drastically changed by changing solution concentration and preparation conditions. 相似文献
143.
Yasuki Kakishita Kazutoshi Sasahara Tetsuro Nishino Miki Takahasi Kazuo Okanoya 《Data mining and knowledge discovery》2009,18(3):446-471
We propose an efficient automata-based approach to extract behavioral units and rules from continuous sequential data of animal
behavior. By introducing novel extensions, we integrate two elemental methods—the N-gram model and Angluin’s machine learning algorithm into an ethological data mining framework. This allows us to obtain the
minimized automaton-representation of behavioral rules that accept (or generate) the smallest set of possible behavioral patterns
from sequential data of animal behavior. With this method, we demonstrate how the ethological data mining works using real
birdsong data; we use the Bengalese finch song and perform experimental evaluations of this method using artificial birdsong
data generated by a computer program. These results suggest that our ethological data mining works effectively even for noisy
behavioral data by appropriately setting the parameters that we introduce. In addition, we demonstrate a case study using
the Bengalese finch song, showing that our method successfully grasps the core structure of the singing behavior such as loops
and branches.
Yasuki Kakishita and Kazutoshi Sasahara have contributed equally to this work. 相似文献
144.
Team performance modeling for HRA in dynamic situations 总被引:1,自引:0,他引:1
This paper proposes a team behavior network model that can simulate and analyze response of an operator team to an incident in a dynamic and context-sensitive situation. The model is composed of four sub-models, which describe the context of team performance. They are task model, event model, team model and human–machine interface model. Each operator demonstrates aspects of his/her specific cognitive behavior and interacts with other operators and the environment in order to deal with an incident. Individual human factors, which determine the basis of communication and interaction between individuals, and cognitive process of an operator, such as information acquisition, state-recognition, decision-making and action execution during development of an event scenario are modeled. A case of feed and bleed operation in pressurized water reactor under an emergency situation was studied and the result was compared with an experiment to check the validity of the proposed model. 相似文献
145.
Calculation of DC Magnetic Flux Deviation in the Converter-Transformer of a Self-Commutated BTB System During Single-Line-to-Ground Faults 总被引:1,自引:0,他引:1
This paper deals with a 50-MW self-commutated Back-To-Back (BTB) system intended for power-flow control between transmission networks. It focuses on the dynamic behavior of the BTB system during single-line-to-ground (SLG) faults that often result in voltage sags. A non-negligible amount of dc magnetic flux deviation appears in the converter-transformers of the BTB system just after the occurrence and restoration of an SLG fault. The dc deviation may bring magnetic flux saturation and an excessive magnetizing current to the transformers. This paper derives theoretical equations related to the dc deviation with reasonable approximation. The theoretical results are confirmed by computer simulation. 相似文献
146.
147.
Ichitaro Ogawa Hisayoshi Yoshida Kazuo Kobayashi Michio Inagaki 《Journal of Materials Science》1985,20(2):414-420
Phenolic resins and the benzene-soluble fraction of a coal tar pitch were mixed in a solvent (pyridine) and carbonized at 600° C in a gold tube under a pressure of 30 MPa. Yields, optical textures and graphitizabilities of the carbons were studied. Large carbon yields (>80%) were obtained from sealed tubes under pressure (closed system). In open tubes under pressure (open system), only slight improvements in carbon yields were observed. As the resin content in the starting mixtures increased, the optical texture of the resultant carbons decreased from coarse mosaic to isotropic through intermediates with a gradual decrease in size of mosaic units. These intermediate optical textures occurred with a wider range of resin content under pressure than under atmospheric pressure, especially from closed systems. Changes in structural parameters of the carbons after the 2800° C treatment corresponded to the changes in optical texture with resin content. 相似文献
148.
Both visual and auditory information are important for songbirds, especially in developmental and sexual contexts. To investigate bimodal cognition in songbirds, the authors conducted audiovisual discrimination training in Bengalese finches. The authors used two types of stimulus: an "artificial stimulus," which is a combination of simple figures and sound, and a "biological stimulus," consisting of video images of singing males along with their songs. The authors found that while both sexes predominantly used visual cues in the discrimination tasks, males tended to be more dependent on auditory information for the biological stimulus. Female responses were always dependent on the visual stimulus for both stimulus types. Only males changed their discrimination strategy according to stimulus type. Although males used both visual and auditory cues for the biological stimulus, they responded to the artificial stimulus depending only on visual information, as the females did. These findings suggest a sex difference in innate auditory sensitivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
Origin of the Red Color of Satsuma Copper-Ruby Glass as Determined by EXAFS and Optical Absorption Spectroscopy 总被引:1,自引:0,他引:1
Izumi Nakai Chiya Numako Hideo Hosono Kazuo Yamasaki 《Journal of the American Ceramic Society》1999,82(3):689-695
The origin of the ruby color of Satsuma glass, a famous copper-ruby glass produced in Japan in the mid-19th century, has been examined by electron microprobe analysis (EPMA), X-ray absorption fine structure (XAFS), and optical absorption spectroscopy analyses. Cu K XAFS analysis reveals that the major component of copper in the ruby glass consists of Cu(I) ions in the glass structure. This species is distinct from Cu2 O (cuprite), which we conclude is not responsible for the ruby color. Optical absorption spectra measured at 300 and 77 K clearly distinguishes the absorptions due to the colloidal particles of metallic copper and Cu2 O. It is concluded that the trace amount of copper in the ruby glass, which is below the detection limit of the EPMA and XAFS techniques, exists as metallic copper particles of nanometer size and is responsible for the ruby-red appearance of the Satsuma glass. 相似文献
150.
Kazuo Taki Tatsuhiro Seki Sakiyori Mononobe Kohichi Kato 《Water science and technology》2008,57(1):19-25
Any kind of blue-green alga produces metabolites of musty substances and toxins. Therefore, it is necessary to remove the blue-green algae, and processing also including nutrient removal is desired for the water quality improvement of eutrophic lakes. The purpose of this study has been to investigate the possibility of a flotation system using a hybrid technique (chemical compounds and electrostatic bridge) applied to raw water containing phytoplankton with high pH of water, and to examine the zeta potential value of phytoplankton surface and the removal efficiency for phytoplankton, ammonia, nitrogen, and phosphoric acid.The results were as follows: firstly, zeta potential of M. aeruginosa particles was observed to achieve charge neutralization on their surface by adhesion of magnesium hydroxide precipitation with increasing pH. Secondly, maximum removal efficiency concerning chlorophyll-a was observed as 84%, and this efficiency was obtained in the condition of pH > 10, and magnesium hydroxide precipitation was observed. Thirdly, in the pH condition that the maximum removal efficiency of chlorophyll-a was obtained, the removal efficiency and the amount of decrease of NH(4)-N and PO(4)-P before and after the change of pH values were observed as 6.7% (0.04 mg-P/L) and 63.6% (0.07 mg-N/L), respectively. 相似文献