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41.
Japanese/English Cross-Language Information Retrieval: Exploration of Query Translation and Transliteration 总被引:1,自引:0,他引:1
Cross-language information retrieval (CLIR), where queriesand documents are in different languages, has of late become one ofthe major topics within the information retrieval community. Thispaper proposes a Japanese/English CLIR system, where we combine aquery translation and retrieval modules. We currently target theretrieval of technical documents, and therefore the performance of oursystem is highly dependent on the quality of the translation oftechnical terms. However, the technical term translation is stillproblematic in that technical terms are often compound words, and thusnew terms are progressively created by combining existing basewords. In addition, Japanese often represents loanwords based on itsspecial phonogram. Consequently, existing dictionaries find itdifficult to achieve sufficient coverage. To counter the firstproblem, we produce a Japanese/English dictionary for base words, andtranslate compound words on a word-by-word basis. We also use aprobabilistic method to resolve translation ambiguity. For the secondproblem, we use a transliteration method, which corresponds wordsunlisted in the base word dictionary to their phonetic equivalents inthe target language. We evaluate our system using a test collectionfor CLIR, and show that both the compound word translation andtransliteration methods improve the system performance. 相似文献
42.
This letter presents a new algorithm for blind dereverberation and echo cancellation based on independent component analysis (ICA) for actual acoustic signals. We focus on frequency domain ICA (FD-ICA) because its computational cost and speed of learning convergence are sufficiently reasonable for practical applications such as hands-free speech recognition. In applying conventional FD-ICA as a preprocessing of automatic speech recognition in noisy environments, one of the most critical problems is how to cope with reverberations. To extract a clean signal from the reverberant observation, we model the separation process in the short-time Fourier transform domain and apply the multiple input/output inverse-filtering theorem (MINT) to the FD-ICA separation model. A naive implementation of this method is computationally expensive, because its time complexity is the second order of reverberation time. Therefore, the main issue in dereverberation is to reduce the high computational cost of ICA. In this letter, we reduce the computational complexity to the linear order of the reverberation time by using two techniques: (1) a separation model based on the independence of delayed observed signals with MINT and (2) spatial sphering for preprocessing. Experiments show that the computational cost grows in proportion to the linear order of the reverberation time and that our method improves the word correctness of automatic speech recognition by 10 to 20 points in a RT??= 670 ms reverberant environment. 相似文献
43.
M. Aoyama J. Temuujin M. Senna T. Masuko C. Ando H. Kishi 《Journal of Electroceramics》2006,17(1):61-64
Z-type hexaferrites (Ba3(1 − x)Sr3x
Co2Fe24O41with x = 0–0.5, Z-hex) were prepared in a nearly phase pure state by a two-step calcination with an intermediate wet milling. The
first calcination of the starting mixture comprising oxides or hydroxides at temperatures below 1100∘C brought about a mixture of layer-structured M and Y-type hexaferrite phases, together with a spinel phase of Co ferrite.
Z-hex was fully crystallized after the second calcination up to 1230∘C. Wet milling between the two calcination steps was decisive for the phase purity. Emphasis was laid on the quantitative
analyses of Z-hex, together with the evaluation of anisotropic growth of the crystallites. Sr addition stabilizes Z-hex, while
decreases degree of anisotropy simultaneously. 相似文献
44.
Baku Katagiri Tetsuya Miyashita Takahiro Ishinabe Tatsuo Uchida 《Journal of the Society for Information Display》2003,11(3):585-590
Abstract— One problem with front‐projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front‐projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room. 相似文献
45.
Shun-ichi Nakamura Tetsuya Hosaka Kenji Nishiumi 《Canadian Metallurgical Quarterly》2004,9(3):297-303
Bending behavior of steel pipes filled with ultralight mortar was studied by bending tests using a steel pipe, steel pipes filled with ultralight mortar, and steel pipes filled with light aggregate concrete and normal concrete. The steel pipe model filled with normal concrete had 1.8 times higher bending strength than the steel pipe model. The bending behavior of the steel pipe filled model with ultralight mortar was not improved when the compressive strength of the ultralight mortar was less than 1 MPa. However, ductility was much improved when the compressive strength was over 5 MPa, and the ultimate steel strain was more than double of the steel pipe model. The strains of steel and concrete in all the models were proportional to the distance from the neutral axis until the steel plate yielded. A simple analytical method was proposed to calculate the bending moments of the ultralight mortar filled steel pipes. The calculated values agreed very well with the test results. 相似文献
46.
Tetsuya Nakatoh Sachio Hirokawa Toshiro Minami Takeshi Nanri Miho Funamori 《Artificial Life and Robotics》2018,23(2):235-240
Investigating the relevant literature is very important for research activities. However, it is difficult to select the most appropriate and important academic papers from the enormous number of papers published annually. Researchers search paper databases by combining keywords, and then select papers to read using some evaluation measure—often, citation count. However, the citation count of recently published papers tends to be very small because citation count measures accumulated importance. This paper focuses on the possibility of classifying high-quality papers superficially using attributes such as publication year, publisher, and words in the abstract. To examine this idea, we construct classifiers by applying machine-learning algorithms and evaluate these classifiers using cross-validation. The results show that our approach effectively finds high-quality papers. 相似文献
47.
Toru Moriyama Jun-ichi Mashiko Toshinori Matsui Koichiro Enomoto Tetsuya Matsui Kojiro Iizuka Masashi Toda Yukio Pegio Gunji 《Artificial Life and Robotics》2016,21(3):247-252
The soldier crab appears in great numbers and feeds while wandering during daytime low tide. When they see an approaching object, they screw themselves into the sand. The mechanism of formation of mass wandering has not been clarified. In this study, to investigate if the soldier crabs use visual images of neighbors as a stimulus for wandering, dummy crabs were presented to crabs. In the experiments, one, two, four, or eight dummies were placed in a circle on a sand arena. Each crab was placed in the center of the arena and observed whether it burrowed into the sand or wandered. The proportions of wandering individuals in each experimental treatment were compared with the expected value. Significantly more crabs were wanderers when only two and four dummies were present. This result suggests that soldier crabs chose burrowing or wandering depending on visual image of the distribution of the neighbors. 相似文献
48.
Glycosphingolipids (GSLs) are composed of a mono-, di-, or oligosaccharide and a ceramide and function as constituents of cell membranes. Various molecular species of GSLs have been identified in mammalian cells due to differences in the structures of oligosaccharides. The oligosaccharide structure can vary depending on cell lineage, differentiation stage, and pathology; this property can be used as a cell identification marker. Furthermore, GSLs are involved in various aspects of the immune response, such as cytokine production, immune signaling, migration of immune cells, and antibody production. GSLs containing certain structures exhibit strong immunogenicity in immunized animals and promote the production of anti-GSL antibodies. By exploiting this property, it is possible to generate antibodies that recognize the fine oligosaccharide structure of specific GSLs or glycoproteins. In our study using artificially synthesized GSLs (artGSLs), we found that several structural features are correlated with the antibody-inducing activity of GSLs. Based on these findings, we designed artGSLs that efficiently induce the production of antibodies accompanied by class switching and developed several antibodies that recognize not only certain glycan structures of GSLs but also those of glycoproteins. This review comprehensively introduces the immune activities of GSLs and their application as pharmaceuticals. 相似文献
49.
Goro Aoyama Kiyoshi Fujimoto Kenichi Katono Takuji Nagayoshi Atsushi Baba Kenichi Yasuda 《Journal of Nuclear Science and Technology》2016,53(4):537-545
A prototype ultrasonic liquid film sensor was applied to a high-temperature steam–water two-phase flow experiment. The liquid film sensor was vertically installed in a loop which was connected to HUSTLE, a multi-purpose steam source test facility. The hydraulic diameter of the measurement section was 9.4 mm. The output waveforms of the sensor were acquired with a digital oscilloscope. The fluid temperature and system pressure were kept at 288 °C and 7.2 MPa, respectively, during the experiment. The pulse-echo method was used to calculate the liquid film thickness. The cross-correlation calculation was utilized to determine the time difference between the pulse reflected at the sensor surface and the pulse reflected at the liquid film surface. The time-averaged liquid film thicknesses were less than 0.055 mm in the annular flow condition. The increase of the time-averaged thickness was small with the change of the gas momentum flux. The film thicknesses measured with the sensor were compared with the past experimental results; the former were smaller than one-fourth of the thickness estimated as the mean film thickness. The comparison results suggested that the continuous liquid sublayer thickness was measured with the liquid film sensor. 相似文献
50.
Partial isothermal sections of the Bi-Fe-Ti system at 700 °C and 900 °C were constructed to investigate the reactivity of Fe with Bi-Ti liquid alloy. In the ternary system, three-phase equilibria such as liquid-Fe-Fe2Ti, liquid-Fe2Ti-Bi2FeTi4, and liquid-Bi9Ti8-Bi2FeTi4 were confirmed at both temperatures. The solubility of Fe in liquid Bi at these temperatures is negligibly small. On the other hand, it is notable that the solubility of Fe in liquid Bi containing Ti at 900 °C is much larger and reaches 2.3 mol pct. Then, we measured the electromotive force (emf) between Bi-20 mol pct Ti alloy and pure Ti at 700 °C in equimolar NaCl-KCl where 1 mol pct TiCl2 was added. From the result, the interaction parameter of the liquid phase in the Bi-Ti system and the standard molar Gibbs energies of formation of Bi9Ti8 and Bi2FeTi4 at 700 °C were estimated. 相似文献