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Kazuhiro KazamaAuthor Vitae Miyuki Imada Author VitaeKeiichiro Kashiwagi Author Vitae 《Neurocomputing》2012,76(1):84-92
A novel method is presented to analyze the dynamics of social media, i.e., information diffusion properties, for information recommendation and ranking. In social media such as blogs, various information diffuses over time. As a result, a network structure is constructed. In an information diffusion network, each influential information source has an affected subnetwork whose nodes are reachable from it. We define three information diffusion properties of the subnetwork using the numbers of three types of directed two-edge connected subgraphs, which are basic structures in a directed acyclic graph such as an information diffusion network. Each basic structure type is related to information scattering, information gathering, or information transmission. We visualized and analyzed the structure of information diffusion networks extracted for various topics. Furthermore, we characterized the information diffusion properties by using the rank correlation coefficient, precision, and mean reciprocal rank and mean average precision of three types of information sources: official sites, news articles, and consumer generated media pages. We found that the three information diffusion properties have different characteristics and give priority to different types of information sources. 相似文献
63.
This paper deals with the performance investigation of a silica gel/water-based multi-stage, multi-bed, six-bed adsorption chiller employing re-heat scheme. The innovative chiller is powered by waste heat or renewable energy sources of temperature between 50 and 70 °C along with a coolant of inlet temperature at 30 °C for air-conditioning purpose. The performance of the six-bed adsorption chiller using re-heat scheme is compared with that of the six-bed chiller without re-heat. With the same operating conditions, such as the heat transfer fluid inlet (HTF) temperatures, HTF flow rates, adsorption/desorption cycle time and same chiller physical dimension, it is found that both the cooling capacity (CC) and the coefficient of performance (COP) of the three-stage chiller with re-heat scheme are superior than those of the three-stage chiller without re-heat scheme. 相似文献
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M Nakamura K Kawano Y Kondo I Miura A Kashiwagi S Yamamoto 《Canadian Metallurgical Quarterly》1997,14(6):935-940
We studied immunohistologically the distribution of a Ca2(+)-binding protein, calreticulin (CLT), at different stages of growing oocytes in the frog, Rana rugosa. Northern blot analysis showed that the CLT gene expression in gonads of metamorphosing tadpoles was low, but was extremely strong in the ovary, but not in the testis, of 2-month post-metamorphosis frogs, followed by decline to a lower level in adult frogs. On the contrary, the beta-actin gene expression did not increase in the same ovary. As for the distribution of CLT protein, a weak immunostaining was observed in indifferent gonads of tadpoles at stage I. The CLT distribution in oocytes from stage A to F was stage-dependent. In addition, Western blot analysis revealed that the CLT level was low in gonads of tadpoles at stage I, but increased at stage XVI. It still increased in the ovary of frogs 2 months after metamorphosis, and then dropped to a lower level in adult frogs. The results indicate that CLT gene expression occurs in the early stage of growing oocytes, and that CLT is synthesized actively in oocytes in the ovary of frogs after metamorphosis. Based on these findings, the role of CLT is discussed. 相似文献
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The effects of resin molecular weight on the flame‐retardant mechanism of silica were studied with two different molecular weights of poly(methyl methacrylate) (PMMA), 122,000 and 996,000 g/mol, and two silicas, fused silica with a small surface area and silica gel with a large surface area. A total of six different samples were studied, with a mass fraction of 10% silica. The mass loss rate of the six samples in nitrogen and the heat release rate from burning in air were measured at an external radiant flux of 40 kW/m2. The addition of silica gel to the low‐molecular‐weight PMMA significantly reduced the mass loss rate and heat release rate; addition to the high‐molecular‐weight PMMA provided the largest reductions of these quantities in this study. For fused silica, some reduction in mass loss rate and heat release rate was observed when it was added to the high‐molecular‐weight PMMA; addition to the low‐molecular‐weight PMMA did not reduce either loss rate. Chemical analysis of the collected residues and observation of the sample surface during gasification reveal the accumulation of silica near the surface; the larger its coverage over the sample surface was, less the mass loss rate and heat release rate were. Both the level of accumulation and its surface coverage depended strongly not only on the silica characteristics but also on the melt viscosity of the PMMA. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1541–1553, 2003 相似文献
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We investigated the hypothesis that interferon-induced hyperadrenergic state causes cardiovascular events. Thirteen patients with chronic hepatitis C who were scheduled to undergo interferon therapy were randomly selected for this study. Heart rate was monitored and urinary levels of catecholamines were measured before, on the 1st day, and after 1 week and 4 weeks of treatment. On the 1st day, 24-hr average heart rate and hourly average heart rate were significantly higher than those before treatment, although they returned to baseline levels after 1 week and 4 weeks. However, urinary levels of cathecholamines did not change significantly on the 1st day of interferon therapy. Although the direct evidence that interferon stimulates sympathetic nervous system could not be obtained, interferon elicited tachycardic response and may have increased the risk of arrhythmias of the 1st day of the treatment. 相似文献
69.
Synthetic polymeric materials are rapidly replacing more traditional inorganic materials, such as metals, and natural polymeric materials, such as wood. As these synthetic materials are flammable, they require modifications to decrease their flammability through the addition of flame-retardant compounds. Environmental regulation has restricted the use of some halogenated flame-retardant additives, initiating a search for alternative flame-retardant additives. Nanoparticle fillers are highly attractive for this purpose, because they can simultaneously improve both the physical and flammability properties of the polymer nanocomposite. We show that carbon nanotubes can surpass nanoclays as effective flame-retardant additives if they form a jammed network structure in the polymer matrix, such that the material as a whole behaves rheologically like a gel. We find this kind of network formation for a variety of highly extended carbon-based nanoparticles: single- and multiwalled nanotubes, as well as carbon nanofibres. 相似文献
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