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991.
Guided modes of a width-reduced photonic-crystal slab line-defect waveguide with asymmetric cladding
Tanaka Y. Sugimoto Y. Ikeda N. Nakamura H. Watanabe Y. Asakawa K. Inoue K. 《Lightwave Technology, Journal of》2005,23(9):2749-2755
The authors fabricated GaAs-based width-reduced photonic-crystal (PC) slab line-defect waveguides with asymmetric cladding, characterized optically by broadband transmission spectral results. These waveguides were vertically sandwiched between air and oxide claddings. Transmission peaks originating from the guided mode located within the bandgap were observed, thereby showing the presence of a bandgap effect for the transverse-electric (TE)-like guided mode even with the coexistence of a fundamental transverse-magnetic (TM)-like mode. Propagation loss spectra were derived from transmission spectra for both TE and TM polarization inputs. Comparing the obtained spectra to band diagrams, the authors detected a mini-stopband effect in the transmission spectra arising from a folding of the fundamental TM-like mode at the Brillouin zone boundary. The coupling coefficient was then estimated to be /spl sim/0.01 [a/sup -1/] (with a being a lattice constant). Dips in spectral intensity were also observed and were attributed to TE-TM mode conversion based on a comparison to the band diagram. 相似文献
992.
993.
Teruo Matsushita Shin-ichi Inoue Ryusuke Tanaka 《Journal of the American Oil Chemists' Society》2010,87(9):963-972
A method for the determination of the total lipid content in fish meat was established using a 2-thiobarbituric acid (TBA)
reaction, which had previously been used for the determination of lipid peroxides in animal tissues. In this method, an unspecific
peroxidation of fish oils was created by omitting the addition of antioxidant to the reaction mixture during the TBA reaction,
because fish meat is more sensitive to the TBA reaction due to its higher concentration of polyunsaturated fatty acids, especially
docosahexaenoic acid and eicosapentaenoic acid, which can easily react artificially with TBA in the absence of an antioxidant
in the assay system. As for a practical application of this method, we tried to optimize the assay procedures in the sampling,
reaction, and detection steps of this method, and finally proposed a new standard procedure recommended for determining the
total lipid content of fish using a TBA reaction. In order to confirm the accuracy of the new procedure, comparative evaluations
for the lipid contents of commercially available fish, i.e., chub mackerel (Scomber japonicus) and saury (Cololabis saira) were made between the conventional procedure and the recommended TBA method. The lipid contents obtained by the two methods
coincided well with high correlation. This method is relevant for total lipid content analysis of fish meat under restricted
laboratory conditions. 相似文献
994.
The longest-chain polyyne that has ever been synthesized is C24H2 by Estmond et al. [1] using the complicated acetylene coupling method. On the other hand, in simple liquid-phase laser ablation method, we have recently obtained the longest-chain polyyne of C22H2. In the present study, we report the synthesis of long-chain polyynes of C24H2 and C26H2 from graphite pellets in solvent of decalin by liquid-phase laser ablation. It is believed that the termination reaction on both ends of these polyyne molecules hardly occurs in decalin with relatively less number of hydrogen atoms and these long-chain polyynes could be synthesized. 相似文献
995.
A 0.4C–2Si–1Cr–1Mo steel bar with an ultrafine-elongated grain (UFEG) structures was produced by multi-pass warm caliber rolling. The test sample was machined from the rolled bar with 0°, 45°, and 90° rotation along the rolling direction, and a static three-point bending test was conducted at ambient temperature. The toughness anisotropy on the steel with UFEG structures were studied, including the crack propagation on the basis of the microstructural features. The strength and toughness decreased with an increase in the rotation angle along the rolling direction. The toughness decreased drastically, compared to the strength. The notch orientation dependence on toughness is due to differences in the spatial distribution of weak sites such as {100} cleavage planes and boundaries of elongated grains. For the toughness design in ultrafine-grained materials, it is essential to understand the spatial distribution of these weak sites as well as the grain size. 相似文献
996.
Study on detection for the defects of XLPE cable lines 总被引:1,自引:0,他引:1
Uchida K. Kobayashi S. Kawashima T. Tanaka H. Sakuma S. Hirotsu K. Inoue H. 《Power Delivery, IEEE Transactions on》1996,11(2):663-668
This paper reports the results of a basic study of testing methods to replace the DC after laying test that is presently most frequently used as an after laying test for XLPE power cable lines. Chosen as the alternative waveforms for DC voltage were damped oscillating wave (OSW) and very-low-frequency wave (VLF) voltages. Experiments were conducted on the ability to detect various types of line defects under these voltages. It was found that these alternative waveforms are promising as after laying test voltage waveforms to replace DC and that greater defect detection ability can be achieved by combining them when conducting tests 相似文献
997.
Debajit Datta Lalit Garg Kathiravan Srinivasan Atsushi Inoue G. Thippa Reddy M. Praveen Kumar Reddy K. Ramesh Nidal Nasser 《计算机、材料和连续体(英文)》2021,67(1):723-751
The prodigious advancements in contemporary technologies have also brought in the situation of unprecedented cyber-attacks. Further, the pin-based security system is an inadequate mechanism for handling such a scenario. The reason is that hackers use multiple strategies for evading security systems and thereby gaining access to private data. This research proposes to deploy diverse approaches for authenticating and securing a connection amongst two devices/gadgets via sound, thereby disregarding the pins’ manual verification. Further, the results demonstrate that the proposed approaches outperform conventional pin-based authentication or QR authentication approaches. Firstly, a random signal is encrypted, and then it is transformed into a wave file, after which it gets transmitted in a short burst via the device’s speakers. Subsequently, the other device/gadget captures these audio bursts through its microphone and decrypts the audio signal for getting the essential data for pairing. Besides, this model requires two devices/gadgets with speakers and a microphone, and no extra hardware such as a camera, for reading the QR code is required. The first module is tested with real-time data and generates high scores for the widely accepted accuracy metrics, including precision, Recall, F1 score, entropy, and mutual information (MI). Additionally, this work also proposes a module helps in a secured transmission of sensitive data by encrypting it over images and other files. This steganographic module includes two-stage encryption with two different encryption algorithms to transmit data by embedding inside a file. Several encryption algorithms and their combinations are taken for this system to compare the resultant file size. Both these systems engender high accuracies and provide secure connectivity, leading to a sustainable communication ecosystem. 相似文献
998.
The rationalization of various aspects of the mechanism of chirality induction in supramolecular assemblies based upon the complexes formed between an ethane-linked bisoctaethylporphyrin and chiral ligands is described. The influence of various controlling factors such as bonding strength, host-guest steric interactions, equilibria and thermodynamic parameters, temperature and solvent effects, role of the center metal ion, stoichiometry, and phase transition on the chirality induction processes have been investigated, and the results and implications are discussed. As a result of such detailed understanding, it is possible to employ this bisporphyrin system as an effective chirality sensor for the determination of absolute configuration. 相似文献
999.
In this paper, we build the intake manifold model of an engine with a turbo charger and develop a high speed calculation algorithm for model‐based predictive control in real time. The model is built according to the analysis of its thermodynamic and hydrodynamic characteristics and the sampled experiment data. The model equations are presented as a set of differential equations with condition selection (bifurcation) on the right hand side. The switching surface is divided into two parts, sliding and crossing. The sliding mode on the switching surface is analyzed in detail, and a calculation algorithm is proposed to remove illegal crossing caused by the numerical errors on this surface. Also, the control formula and the condition guiding the bifurcation between these two parts are demonstrated. Using this method, we can solve this model over the entire region of input throttle angles, the stability is greatly increased, and the calculation time is greatly reduced for real time control systems. 相似文献
1000.