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11.
A potential barrier model along the grain boundaries in ultrathin tin dioxide (SnO2) gas sensors is presented. It is assumed that the negatively charged oxygens are adsorbed only on the grain boundaries. The
potential barrier depth is expressed as functions of grain size, donor concentration and surface coverage of adsorbed oxygen
ions at the boundaries. A direct consequence is that the conduction electrons are effectively confined in a grain when the
film thickness becomes smaller than a critical value. This indicates a drastic increase in resistivity with decreasing film
thickness in air, and thus an occurrence of an extremely high gas sensitivity. 相似文献
12.
Nakamura K. Kuhara S. Kimura T. Takada M. Suzuki H. Yoshida H. Yamazaki T. 《Solid-State Circuits, IEEE Journal of》1994,29(11):1317-1322
This 512 Kw×8 b×3 way synchronous BiCMOS SRAM uses a 2-stage wave-pipeline scheme, a PLL self-timing generator and a 0.4-μm BiCMOS process to achieve 220 MHz fully-random read/write operations with a GTL I/O interface. Newly developed circuit technologies include: 1) a zig-zag double word-line scheme, 2) a centered bit-line load layout scheme, and 3) a phase-locked-loop (PLL) with a multistage-tapped ring oscillator which generates a clock cycle proportional pulse (CCPP) and a clock edge lookahead pulse (CELP) 相似文献
13.
14.
15.
T Ohtsuka N Koibuchi S Matsuzaki A Yamakage S Yamazaki 《Canadian Metallurgical Quarterly》1998,139(6):1047-1048
Using in situ hybridization techniques, we examined the expression of ornithine decarboxylase (ODC) mRNA in the skin of five patients with systemic sclerosis (SSc) and five normal controls. Sections treated with an anti-sense probe showed concentrated grains exclusively in the epidermis of SSc patients, but not in that of normal controls. Because our subcloned anti-sense probe specifically hybridizes with ODC mRNA, these findings indicate that the expression of ODC mRNA is elevated in SSc epidermis. Possibly polyamines have an important part to play in the skin changes of SSc. 相似文献
16.
The preparation and characterization of indium oxide (InO
x
)/tin oxide (SnO
y
) multilayered films deposited by ion-beam sputtering are described and compared with indium tin oxide (ITO) films. The structure and the optoelectrical properties of the films are studied in relation to the layered structures and the post-deposition annealing. Low-angle X-ray diffraction analysis showed that most films retained the regular layered structures even after annealing at 500° C for 16 h. As an example, we obtained a resistivity of 6×10–4 cm and a transparency of about 85% in the visible range at a thickness of 110 nm in a multilayered film of InO
x
(2.0 nm)/SnO
y
(0.2 nm)×50 pairs when annealed at 300° C for 0.5 h in air. Hall coefficient measurements showed that this film had a mobility of 17 cm2 V–1 sec–1 and a carrier concentration (electron density) of 5×1020 cm–3. 相似文献
17.
Kikuo Maekawa Makoto Yamazaki Toshinobu Ogiso Takehiko Maruyama Hideki Ogura Wakako Kashino Hanae Koiso Masaya Yamaguchi Makiro Tanaka Yasuharu Den 《Language Resources and Evaluation》2014,48(2):345-371
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses. 相似文献
18.
The plasmodium of Physarum polycephalum is a unicellular and multinuclear giant amoeba that has an amorphous cell body. To clearly observe how the plasmodium makes decisions in its motile and exploratory behaviours, we developed a new experimental system to pseudo-discretize the motility of the organism. In our experimental space that has agar surfaces arranged in a two-dimensional lattice, the continuous and omnidirectional movement of the plasmodium was limited to the stepwise one, and the direction of the locomotion was also limited to four neighbours. In such an experimental system, a cellular automata-like system was constructed using the living cell. We further analysed the exploratory behaviours of the plasmodium by duplicating the experimental results in the simulation models of cellular automata. As a result, it was revealed that the behaviours of the plasmodium are not reproduced by only local state transition rules; and for the reproduction, a kind of historical rule setting is needed. 相似文献
19.
Tomohiro Hashiguchi Yutaka Takita Kazuyuki Tajima Toru Katagiri 《Journal of Network and Systems Management》2016,24(3):557-577
Shared protection/restoration is a promising solution for reducing protection resources and is supported at each layer of the current multi-layer networks. Software-defined networking is expected to reduce equipment cost as well as operational cost by orchestrating these shared protection functionalities. However, although protection resource sharing improves link utilization, it sometimes increases the required equipment. Meanwhile, traffic re-aggregation at each layer is an important technique for low volume traffic to utilize the underlying link capacity more efficiently, but re-aggregation also makes it difficult to share protection resources with traffic at lower layers. In this paper, we present multi-layer network design strategy and method that reduce equipment cost by means of both traffic re-aggregation at each layer and protection resource sharing among multiple service traffic at different layers. The strategy first prioritizes traffic re-aggregation at each layer, and then maximally delegates shared protection to lower layers as long as it does not increase the required capacity at the lower layer. Evaluation results from the example three-layer networks confirm that the proposed method can effectively reduce equipment cost compared to the conventional design method. Cost reduction is achieved by leveraging shared protection functions at multiple layers. 相似文献
20.