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71.
The polarization characteristics of a terahertz (THz) wave transmitted through two-dimensional (2-D) metallic photonic crystals (MPCs) are investigated. The 2-D MPCs studied in this paper are metal slabs perforated periodically with circular holes. We measured the polarization characteristics of the THz wave using a THz time-domain spectroscopic system with wire grid polarizers in the time and frequency domains. The linearly polarized incident THz wave changes its polarization direction and becomes elliptic after it transmits through the sample. This phenomenon is highly sensitive to the incident angle. It is shown that the frequency range at which the polarization rotation occurs is related to the lattice constant of a photonic crystal, indicating the importance of photonic band modes of the 2-D MPC in the mechanism of the phenomenon. 相似文献
72.
Noriyuki?Aibe Ryosuke?Mizuno Masanori?Nakamura Moritoshi?YasunagaEmail author Ikuo?Yoshihara 《Artificial Life and Robotics》2004,8(2):208-213
The probabilistic neural network (PNN) is one of the most promising neural networks, and is now applied to some real-world applications. In order to speed up the PNN calculation considerably, we have developed a PNN hardware system for video image recognition. The performance of the PNN hardware cannot be evaluated precisely until the evaluation system is completed. In this study, we developed a performance evaluation system for the PNN hardware and demonstrated it using the developed evaluation system.This work was presented, in part, at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003 相似文献
73.
Masanori?SugisakaEmail author Kouta?Imamura Kouji?Tokuda Maoki?Masuda 《Artificial Life and Robotics》2004,8(1):1-4
Recently, a biologically inspired, bipedal, dynamic, humanoid robot was developed at the Artificial Life and Robotics Laboratory of Oita University. This bipedal humanoid robot is able to walk dynamically and to go up and down stairs. The central pattern generator developed produces various types of walking pattern. This robot has a pair of small CMOS color CCD cameras, a speaker, and a microphone in the head part, and will have a GPS, a portable telephone, and other sensors in the body part, so that the integration of locomotion and behavior to achieve specific demonstrations will be realized. This project develops dynamic mobility and the ability for autonomous recognition and navigation using the biological central nervous system, the brain system, and the real-time control system. Also, the design principles that demonstrate the dynamic interaction between neural and mechanical controls will be clarified. In Phase I, the platform of a small, bipedal, humanoid robot is used to develop autonomous locomotion and autonomous sensing and navigation. In Phase II of the project, an iteration on the platform design for human-size, bipedal, humanoid robots will be performed for operational testing. The development of bipedal humanoid robots that capture biological systems with unique principles and practices could dramatically increase their performance in tasks for national security needs.This work was presented in part at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003 相似文献
74.
Soybean and milk proteins modified by transglutaminase improves chicken sausage texture even at reduced levels of phosphate 总被引:2,自引:0,他引:2
Muguruma M Tsuruoka K Katayama K Erwanto Y Kawahara S Yamauchi K Sathe SK Soeda T 《Meat science》2003,63(2):191-197
Consumer demands for poultry processed meats have increased due to low fat content. In this experiment, chicken sausages were manufactured with various biopolymers prepared from soybean protein, casein, whey protein isolate (WPI), mixtures of soybean protein and casein, and soybean protein and WPI. The extent of various biopolymer formations was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high performance liquid chromatography. Cross-linking soybean protein and casein or WPI by transglutaminase provided biopolymers with improved heat stability and emulsifying property. Shear force of chicken sausages were measured to evaluate the addition of biopolymer on the hardness in the presence of 0.05 or 0.2% sodium tripolyphosphate (STPP). The texture of chicken sausages was improved by the addition of such biopolymers even in the presence of 0.05% STPP. These results suggested that chicken sausage texture was improved by the formation of network structures that contribute to hardness of sausage gels with the addition of biopolymers. Thus, addition of biopolymers in the manufacture of chicken sausages may permit reduction in phosphate content without loss in texture. 相似文献
75.
Maruyama T Shirota O Kawahara N Yokoyama K Makino Y Goda Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):44-48
'Magic mushrooms' (MMs) are psychoactive fungi containing the hallucinogenic compounds, psilocin (1) and psilocybin (2). Since June 6, 2002, these fungi have been regulated by the Narcotics and Psychotropics Control Law in Japan. Because there are many kinds of MMs and they are sold even as dry powders in local markets, it is very difficult to identify the original species of the MMs by morphological observation. Therefore, we investigated the internal transcribed spacer (ITS) region in the ribosomal RNA gene of MMs obtained in Japanese markets to classify them by a genetic approach. Based on the size and nucleotide sequence of the ITS region amplified by PCR, tested MMs were classified into 6 groups. Furthermore, a comparison of the DNA sequences of the MMs with those of authentic samples or with those found in the databases (GenBank, EMBL and DDBJ) made it possible to identify the species of tested MMs. Analysis by LC revealed that psilocin (1) was contained at the highest level in Panaeolus cyanescens among the MMs, but was absent in the Amanita species. 相似文献
76.
Ichikawa S Akita T Okumura M Haruta M Tanaka K Kohyama M 《Journal of electron microscopy》2003,52(1):21-26
Three-dimensional (3-D) nanostructures of gold catalysts supported on TiO2 were analysed by electron holography and high-resolution electron microscopy. The contact angle of the gold particle on TiO2 tended to be >90 degrees in the case of gold particles with a size (height) of >4 nm and it tended to be <90 degrees for gold particles with a height of <2 nm. The change in morphology increases the perimeter at the Au/TiO2 interface as the particle size decreases. This change in 3-D structure should be attributed to a change in electronic structure at the interface. It was found that electron holography enabled 3-D analysis at the atomic level and was effective for analysing nanostructured particles. 相似文献
77.
Calcination of oxovanadylphthalocyanine at 500-1000 °C under an argon atmosphere was performed. Elemental analyses, XRD and TEM measurements revealed that the calcined materials are composed of nano-sized vanadium nitride and carbon clusters. ESR spectral examinations suggested that the calcined materials have a photo-responsive charge separation feature. The decomposition of methylene blue and trimethylhydroquinone in the presence of the material calcined at 900 °C was accelerated by visible light irradiation. H2 evolution was detected from a mixture of the calcined material and water under the visible light irradiation. 相似文献
78.
Masanori Katagiri Shigeyuki Izumi Jun’ya Hori Yoshiko Fujii Keisaku Hatanaka 《Journal of Low Temperature Physics》2007,148(3-4):127-132
The heat transfer properties of 3He bubbles in the nucleate boiling state have been investigated in liquid 3He below 1.0 K by using the shadowgraph method. The temperature difference between the copper surface and liquid 3He temperature was also measured as a function of heat flux in steady state. The size and number of bubbles departing from
the surface in a specific time were compared using photograph recorded by a high-speed video camera at various heat flux and
liquid 3He temperature of 0.5, 0.7 and 1.0 K. 相似文献
79.
Takuya Otani Kenji Hashimoto Takaya Isomichi Akira Natsuhara Masanori Sakaguchi Yasuo Kawakami 《Advanced Robotics》2013,27(22):1197-1206
In previous studies, various stabilizing control methods for humanoids during the stance phase while hopping and running were proposed. Although these methods contribute to stability while hopping and running, it is possibility that the control during the flight phase could also affect the stability. In this study, we investigated whether the control during the flight phase can affect the stability of a humanoid while running. To achieve stable hopping, we developed a control system that accounts for the angular momentum of the whole body during the flight phase. In this system, the angular momentum generated by the motion of the lower body in each time interval is calculated during the flight phase, and the trunk joints are controlled to generate the angular momentum necessary to compensate for the deviation of the waist posture, which is used as the reference point for the motion coordinate system of the robot. Once the proposed control system was developed and simulated, we found that the hopping duration in the unconstrained state was extended. 相似文献
80.
Hyungjin Kim Tomofumi Uto Takami Akagi Masanori Baba Mitsuru Akashi 《Advanced functional materials》2010,20(22):3925-3931
Size‐regulated amphiphilic poly(amino acid) nanoparticles (NPs) composed of poly(γ‐glutamic acid) (γ‐PGA) and the hydrophobic amino acid derivative, L ‐phenylalanine ethyl ester (Phe) are prepared to evaluate the effects of particle size on dendritic cell (DC) uptake of NPs and their immune stimulatory activities as delivery carriers and adjuvants. The size of the Phe‐conjugated γ‐PGA NPs (γ‐PGA–Phe NPs) is easily controlled by regulating the aggregated γ‐PGA–Phe numbers. Each of the differently sized γ‐PGA–Phe NPs could efficiently encapsulate ovalbumin (OVA), and the amount of encapsulated OVA per milligram of NPs is almost the same despite the differences in size. The DC uptake of small NPs is lower than for the larger NPs, but the effect of DC activation by NPs is high in the small sizes. The DC activation is significantly affected by the size of the NPs, which suggests that not only the uptake process of the NPs, but also the surface interactions between the NPs and DCs, is important for the induction of DC maturation. The precisely size‐controllable γ‐PGA–Phe NPs have significant potential as an antigen carrier and vaccine adjuvant. These results should provide guidelines for adjuvant design in the development of an effective vaccine. 相似文献