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81.
Fujimoto J Umeda Y Tamura T Tomiyama T Kimura F 《Environmental science & technology》2003,37(23):5398-5406
To achieve sustainability, resource consumption and waste generation must be drastically decreased. For societal acceptance, preservation of both quality of life and corporate profits are essential. One promising approach is to shift the source of value from the amount of product sold to the quality of services the product provides. This paper describes the need for redesigning recycling systems from a manufacturing perspective and then discusses the possibility of this "servicification" of products, describing our experience with prototype development. We discuss development of product prototypes and their business, using consumer facsimile machines as an example of "service-oriented products". Traditional thought presumes that only products comprising new materials and components are valuable. Consideration of a service-oriented product can serve as a stimulus to revise this mode of thought and to control delivery and quality of disposed products. This paper also provides a life cycle simulation of the developed service-oriented business. Simulation results indicate that service-oriented business can potentially reduce environmental impact while extending business opportunities from the viewpoint of whole product life cycles. 相似文献
82.
All-optical wavelength conversion employing a GaInAsP/InP nonlinear distributed-feedback waveguide switch is investigated. The device has the advantages of simple structure, compactness, polarity-noninverted operation, and feasibility of integration with other photonic devices such as semiconductor optical amplifier and modulators. We show that the device exhibits constant conversion efficiency around -9.2 dB in a signal-wavelength range of 1530-1560 nm. Furthermore, this device can potentially be made polarization independent. 相似文献
83.
Oikawa D Nakanishi T Nakamura Y Takahashi Y Yamamoto T Shiba N Tobisa M Takagi T Iwamoto H Tachibana T Furuse M 《Lipids》2003,38(6):609-614
This study investigated the influence of PUFA on the properties of mouse skin. Mice (3 wk old) were given free access to oils
high in linoleic acid, CLA, or DHA for 4 wk. At the end of the experiment, their skins were compared by both biochemical and
histological methods. No significant differences in lipid and collagen contents were detected among treatments, although the
FA composition in the skin was altered depending upon the FA composition of the supplemented oils. Electron microscopy revealed
that the subcutaneous tissue layers in the CLA and DHA groups were significantly thinner than that in the high linoleic acid
group, whereas no differences in the thickness of dermis layers were observed among the three groups. These results suggest
that skin properties in mice are readily modified by dietary FA sources within 4 wk of dietary oil supplementation. 相似文献
84.
85.
Masaharu Nagayama Tsutomu Ikeda Tetsuya Ishiwata Norikazu Tamura Manshi Ohyanagi 《Journal of Materials Synthesis and Processing》2001,9(3):153-163
In the present paper, by using a mathematical model for self-propagating high-temperature synthesis, we reveal the three-dimensional structure of so-called spin combustion wave on the inside of cylindrical sample. It is shown that an isothermal surface of regular spin combustion wave has some wings of which number is the same as that of reaction spots on the cylindrical surface and that the isothermal surface with helical wings rotates down with time. Because of this propagating pattern, in this paper, we adopt the more suitable term helical wave. We also obtain the following existence conditions of a helical wave: If physical parameters are set so that a pulsating wave exists stably for the one-dimensional problem, then a helical wave takes the place of a pulsating wave when the radius of cylindrical sample becomes large. 相似文献
86.
Shuang Bai Tetsuya Matsumoto Yoshinori Takeuchi Hiroaki Kudo Noboru Ohnishi 《Machine Vision and Applications》2013,24(5):959-970
In image classification based on bag of visual words framework, image patches used for creating image representations affect the classification performance significantly. However, currently, patches are sampled mainly based on processing low-level image information or just extracted regularly or randomly. These methods are not effective, because patches extracted through these approaches are not necessarily discriminative for image categorization. In this paper, we propose to utilize both bottom-up information through processing low-level image information and top-down information through exploring statistical properties of training image grids to extract image patches. In the proposed work, an input image is divided into regular grids, each of which is evaluated based on its bottom-up information and/or top-down information. Subsequently, every grid is assigned a saliency value based on its evaluation result, so that a saliency map can be created for the image. Finally, patch sampling from the input image is performed on the basis of the obtained saliency map. Furthermore, we propose a method to fuse these two kinds of information. The proposed methods are evaluated on both object categories and scene categories. Experiment results demonstrate their effectiveness. 相似文献
87.
S Maruta Y Uyehara K Homma Y Sugimoto K Wakabayashi 《Canadian Metallurgical Quarterly》1999,125(1):177-185
The products of the SOS-regulated umuDC operon are required for most UV and chemical mutagenesis in Escherichia coli, a process that results from a translesion synthesis mechanism. The UmuD protein is activated for its role in mutagenesis by a RecA-facilitated autodigestion that removes the N-terminal 24 amino acids. A previous genetic screen for nonmutable umuD mutants had resulted in the isolation of a set of missense mutants that produced UmuD proteins that were deficient in RecA-mediated cleavage (J. R. Battista, T. Ohta, T. Nohmi, W. Sun, and G. C. Walker, Proc. Natl. Acad. Sci. USA 87:7190-7194, 1990). To identify elements of the UmuD' protein necessary for its role in translesion synthesis, we began with umuD', a modified form of the umuD gene that directly encodes the UmuD' protein, and obtained missense umuD' mutants deficient in UV and methyl methanesulfonate mutagenesis. The D39G, L40R, and T51I mutations affect residues located at the UmuD'2 homodimer interface and interfere with homodimer formation in vivo. The D75A mutation affects a highly conserved residue located at one end of the central strand in a three-stranded beta-sheet and appears to interfere with UmuD'2 homodimer formation indirectly by affecting the structure of the UmuD' monomer. When expressed from a multicopy plasmid, the L40R umuD' mutant gene exhibited a dominant negative effect on a chromosomal umuD+ gene with respect to UV mutagenesis, suggesting that the mutation has an effect on UmuD' function that goes beyond its impairment of homodimer formation. The G129D mutation affects a highly conserved residue that lies at the end of the long C-terminal beta-strand and results in a mutant UmuD' protein that exhibits a strongly dominant negative effect on UV mutagenesis in a umuD+ strain. The A30V and E35K mutations alter residues in the N-terminal arms of the UmuD'2 homodimer, which are mobile in solution. 相似文献
88.
Sn2+-incorporated potassium titanate (K2Ti6O13) nanoribbons were prepared by a facile acid-free ion-exchanged method in a dehydrated methanol solution at room temperature. XRD patterns suggested that K2Ti6O13 (KTO) and Sn2+-incorporated KTO (SKTO) are well crystallized with monoclinic phase structures. The mole ratio of incorporated Sn2+ to K+ in SKTO was estimated to be 2. X-ray photoelectron spectrum showed that the Sn species of SKTO consisted of 90% of Sn2+ and 10% of Sn4+, suggesting that part of Sn2+ was oxidized to Sn4+ in the incorporation process. The band gap of SKTO was 0.7 eV narrower than that of KTO, which was derived from lift of the top of the valence band due to the hybridization of Sn5s and O2p orbitals. The SKTO nanoribbons showed remarkable photocatalytic activities for H2 evolution and rhodamine B degradation under visible light irradiation (λ ≥ 420 nm). The photocatalytic mechanism and durability were studied in detail. The advantage of this acid-free ion-exchange method is ease of ion-exchange of K+ with H+ and maintenance of the integrity of the 1D nanoribbon structures. This method can be applied to preparation of other Sn2+-incorporated compounds with special nanostructures. 相似文献
89.
Na Zhou Takuya Matsumoto Takahiro Hosokawa Tetsuya Suekane 《Flow Measurement and Instrumentation》2010,21(3):262-267
Entrapment of the non-wetting phase in porous media has been observed in a variety of fields such as petroleum engineering, geological storage of carbon dioxide, and remediation of ground water. We investigated gas trapping in porous media from a microscopic point of view. High-resolution, three-dimensional images of pore structure and trapped gas bubbles in Berea sandstones were obtained using a micro-focused X-ray CT scanner. We used vertical and horizontal Berea sandstone cores, 8 mm in diameter and 15 mm long. Based on the three-dimensional image analysis, the statistical distribution of the trapped gas volume was estimated. Trapped bubbles have a pore-network scale size and distribute over several pores. In the case of the vertical core, the porosity fluctuates along the flow direction due to the layered structure. The residual gas saturation also fluctuates with porosity along the flow direction. The higher gas saturation in porous layers at the end of gas injection results in a higher trapped gas saturation compared to dense layers. On the other hand, in dense layers the gas saturation at the end of gas injection is almost the same as residual gas saturation. Therefore, most of the gas injected into the dense layers would be trapped. In the case of the horizontal core, the gas saturation at the irreducible water condition is lower than that for the vertical core, because the injected gas selectively passes through the more permeable layers. However, the residual gas saturation is 29.2% for the horizontal core, which is comparable with that for the vertical core (30.9%). Finally, the effect of capillary number on stability of trapped gas bubbles has been estimated. Trapped gas bubbles are stable against the increased flow rate up to a capillary number of 1.0×10?5. 相似文献
90.
Albert Kochendoerfer Tetsuya Saito Karl Edgar Hagedorn 《Engineering Fracture Mechanics》1972,4(4):665-674
The increase with increasing temperature of KIc, measured with 2CT and 1'CT specimens, from about 103N mm
at 77 K to about 2.103 N mm
at about 170 K is attributed to the increasing proportion of dimple to cleavage fracture as revealed by scanning electron microscope investigation.
The specimens were prestrained to different partial scale yielding states by the same kind of loading, performed at 298 K, as in the later KIctests, performed at 77 K. After pretension KIc = K*Ic is increased by a maximum amount of about half of the value K0Icof nonprestrained specimens, after precompression it is reduced by the same amount if this value is evaluated from the load at which a pop-in occurs. The value KIc = K**Ic for the final fracture lies between K*Ic and K0Ic. These results are interpretated in terms of the residual stress states due to prestraining. 相似文献