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71.
The authors have proposed an architecture for a compact image-capturing system called TOMBO (thin observation module by bound optics), which uses compound-eye imaging for a compact hardware configuration [Appl. Opt. 40, 1806 (2001)]. The captured compound image is decomposed into a set of unit images, then the pixels in the unit images are processed with digital processing to retrieve the target image. A new method for high-resolution image reconstruction, called a pixel rearrange method, is proposed. The relation between the target object and the captured signals is estimated and utilized to rearrange the original pixel information. Experimental results show the effectiveness of the proposed method. In the experimental TOMBO system, the resolution obtained is four times higher than that of the unit image that did not undergo reconstruction processing.  相似文献   
72.
VDE is a homing endonuclease gene originally discovered as an intervening element in VMA1s of Saccharomyces cerevisiae. There have been two independent subfamilies of VDE, one from S. cerevisiae strain X2180-1A and the other from Saccharomyces sp. DH1-1A in the host VMA1 gene, and they share the identity of 96.3%. In order to search the occurrence, intra/interspecies transfer and molecular degeneration of VDE, complete sequences of VMA1 in 10 strains of S. cerevisiae, eight species of saccharomycete yeasts, Candida glabrata and Kluyveromyces lactis were determined. We found that six of 10 S. cerevisiae strains contain VDEs 99.7-100% identical to that of the strain X2180-1A, one has no VDE, whereas the other three harbour VDEs 100% identical to that of the strain DH1-1A. S. carlsbergensis has two VMA1s, one being 99.8% identical to that of the strain X2180-1A with VDE 100% identical to that of the strain DH1-1A and the other containing the same VMA1 in S. pastorianus with no VDE. This and other evidence indicates that intra/interspecies transmissions of VDEs have occurred among saccharomycete yeasts. Phylogenetic analyses of VMA1 and VDE suggest that the S. cerevisiae VDEs had branched earlier than other VDEs from an ancestral VDE and had invaded into the host loci as relatively late events. The two VDEs seemed to degenerate in individual host loci, retaining their splicing capacity intact. The degeneration of the endonuclease domains was distinct and, if compared, its apparent rate was much faster than that of the protein-splicing domains.  相似文献   
73.
For the control of a human-cooperative robot (HCR) using a soft material, we aim to verify, in this study, the usefulness of force estimation via physical properties of an air cushion. First, the physical model of the air cushion was represented by an air cylinder with a piston, which is subject to constraint by nonlinear elasticity. Second, the elastic properties of the air cushion were examined under the assumption that it can be formulated by a function of pneumatic pressure. The force applied to the air cushion was next estimated on the basis of the physical model, and the HCR was successfully controlled according to the estimated force.  相似文献   
74.
Epoxy/zirconia hybrid materials were synthesized from a bisphenol-A type epoxy resin, zirconium-tetra-n-propoxide and acetic acid via in situ polymerization. Acetic acid was used to control the hydrolysis and condensation reaction of the zirconium-tetra-n-propoxide. As a result, the zirconia produced by the in situ polymerization was uniformly dispersed into the epoxy matrix on a nano scale or less, and the hybrid materials exhibited an excellent optical transparency. With the increasing zirconia contents, the storage modulus in the rubbery region increased and the peak area of tanδ in the glass transition temperature region decreased. These results indicate that their heat resistance of the hybrid materials could be improved by hybridization with zirconia. Furthermore, the refractive indices of the hybrid materials were significantly improved with the increasing zirconia contents.  相似文献   
75.
LSI interconnect insulators made using low dielectric constant (low-k) materials are required for high performance devices with a small RC delay. We investigated a boron carbon nitride film containing the methyl group (Me–BCN) using tris-di-methyl-amino-boron (TMAB: B[N(CH3)2]3) gas as a low-k material. In addition, we studied the influence of the methyl group on the dielectric constant (k-value) and the properties of the Me–BCN films. It was found that the k-value of the Me–BCN films decreases with increasing number of C–H bonds due to the methyl group (CH3). The number of O–H bonds due to water incorporation is suppressed by increasing the number of C–H bonds. Consequently, we suggested that a lower k-value can be realized by the suppression of water invasion by a hydrophobic surface due to methyl bonds. Thus, the control of the methyl group is important to achieve a low-k material using Me–BCN films.  相似文献   
76.
The water wettability and non-wettability onto various kinds of polymers, which have so far been macroscopically described by the water contact angle, were investigated using the molecular orbital theory. An atomistic model consisting of an H2O molecule and a selected polymer crystal surface was analyzed in the isolated and the physisorbed states. The degree of interaction between the water molecule and the polymer surface was evaluated by considering the change of Mulliken charge at the oxygen site in the water molecule, and also the work of adhesion during the physisorption process. Such energetic quantities for several polymers were compared with the macroscopic water wettability/non-wettability. We found fairly good agreement between these approaches for the highly non-wettability polymers.  相似文献   
77.
In this study, we characterized polystyrene-binding peptides (PS-tags) that possess a specific binding affinity for hydrophilic polystyrene (phi-PS) plates. Both the FITC-labeled PS19-1 (RAFIASRRIKRP) and PS19-6 (RIIIRRIRR) peptides showed strong binding affinity for commercially available hydrophilic, but not hydrophobic, PS plates in the presence of the non-ionic surfactant Tween 20. The dissociation constants (Kd) of the PS19-1 and PS19-6 peptides for the hydrophilic PS-A plate were 169 and 86 nM, respectively, and the Kd of both peptides increased with the concentration of NaCl or urea. Based on adsorption yield and residual activity of glutathione S-transferase (GST) after fusion with the PS19-6 peptide or its variants, it was found that the basic amino acid in the PS-tags, i.e., Arg was essential for the strong binding affinity of PS-tags in both the peptide and peptide-fused protein forms The aliphatic amino acids in PS19-6 and PS19-6L, such as Ile or Leu, were also effective. Thus, a series of PS-tags that possess this unusual feature, especially the peptides PS19-6 (RIIIRRIRR) and PS19-6L (RLLLRRLRR), are potential candidate affinity peptide tags for site-specific immobilization of proteins onto hydrophilic PS plates, which show potential as solid supports for protein-based biochips.  相似文献   
78.
In this article, we report a new particle-excitation flow control valve. The purpose of this study is the development of a particle-excitation flow control valve that can precisely control pneumatic cylinders. We have reported this flow control valve principle. The valve, driven by a PZT vibrator, has a simple lightweight structure with large flow rate. We report the relationship between the orifice arrangement and flow rate characteristics of the valve. We have designed a new prototype for the purpose of high controllability. We have measured flow-rate characteristics and confirmed the conditions necessary for continuous adjustment of flow quantity. The control valve works successfully to realize a change in flow rate.  相似文献   
79.
80.
A newly proposed energy‐compensating active control is implemented to reduce the return current noise which is caused by inverter‐driven electric car systems. The energy‐compensating active control detects the energy charged at the filter capacitor, and reduces the energy and current of the noise frequency component by simple feedback loop incorporated with the conventional motor torque controller. No additional sensors or circuit arrangements are necessary; therefore, the return current can be attenuated effectively without any further cost. The return current with an inverter system is measured using a current probe and an FFT analyzer, and it is shown that the 25‐Hz noise current is reduced by up to 10 dB with the control. The results reveal that the low‐frequency return current noise can be attenuated with the simple control scheme, which would expectedly reduce the size of filter reactors and capacitors to meet the current limit level of the signaling system's track relays. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 84–91, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20615  相似文献   
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