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1.
Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon.  相似文献   
2.
This article considers the nature of online religion by examining the websites and religious counseling activities conducted by new Japanese religions. Beginning with an overview of the widespread use of the Internet in Japan and its use in religion, the article examines the cultural and social factors that keep the religious use of the Internet from becoming as pervasive in Japan as it is in the U.S. The article then describes a website with elements of online religion and the Internet-based religious counseling services being provided by ministers of the new Shintō-derived religions of Konkōkyō and Tenrikyō. These activities have successfully given some people who need religious assistance access to religious teaching. In concluding, the article examines the reasons for the success of these efforts, as well as the reasons why they have not expanded in scope, in light of the cultural and organizational advantages and disadvantages that affect Internet use.  相似文献   
3.
This work faces the redundancy problem, a central concern in robotics, in a particular force-producing task by using muscle synergies to simplify the control. We extracted muscle synergies from human electromyograph signals and interpreted the physical meaning of the identified muscle synergies. Based on the human analysis results, we hypothesized a novel control framework that can explain the mechanism of the human motor control. The framework was tested in controlling a pneumatic-driven robotic arm to perform a reaching task. This control method, which uses only two synergies as manipulated variables for driving antagonistic pneumatic artificial muscles to generate desired movements, would be useful to deal with the redundancy problem; thus, suggesting a simple but efficient control for human-like robots to work safely and compliantly with humans.  相似文献   
4.
Attention has been increasingly paid to the partial oxidation of lower alkanes to synthesis gas, due to its intrinsic energy saving process. We studied the partial oxidation of ethane (POE) on Co loaded on various supports. The POE performance varied as follows: Y2O3, CeO2, ZrO2, La2O3  SiO2, Al2O3, TiO2 > MgO. Comparing Y2O3 and CeO2, the carbon deposition during the POE was negligible on CeO2 and therefore CeO2 was the most preferable support. By changing space velocity and O2 partial pressure, reaction mechanism of POE was studied and it was revealed that two-step mechanism was prevailing; combustion of ethane to H2O and CO2 and subsequent reforming of ethane with H2O and CO2 to synthesis gas. Co/CeO2 catalyst exhibited high and stable catalytic activity for 10 h; high ethane conversion of 18% (maximum ethane conversion 20% at O2/C2H6 = 0.2) with H2 and CO selectivities of 93 and 84%, respectively.  相似文献   
5.
For the effective use of short-lived radioactive beams, soon to be available at the Tokai Radioactive Ion Accelerator Complex, the authors have developed a radiotracer method for diffusion studies in solids. The experimental test was performed by the measurement of the diffusion coefficients of Li in a sample of the compound βLiAl using an α-emitting radiotracer of 8Li (T1/2=0.84 s). It was found that the time-dependent yields of the α particles from the diffusing 8Li that was initially implanted in the sample could be used as a measure of the diffusivity of the tracer in a nondestructive way. The method was applied to measure the self-diffusion coefficients of Li in βLiGa, and for investigating how the Li diffusion in the Li ionic conductors is affected by the concentration of atomic defects (i.e., the existence of the atomic vacancies of Li and the defects in Ga sites that are replaced by Li).  相似文献   
6.
Microchannel (MC) emulsification is a promising technique for producing monodisperse emulsions consisting of highly uniform droplets. The authors developed a high-aspect-ratio microstructure (HARMST) made of poly(methyl methacrylate) (PMMA) as a new MC emulsification device. A PMMA straight-through MC array plate consisting of 31,250 through-holes with a 7.3 × 22.9-μm oblong section and a 200-μm depth was fabricated by a process of synchrotron radiation (SR) lithography and etching. Oblong MCs fabricated in a PMMA straight-through MC array were highly uniform with a coefficient of variation of less than 2%. The fabricated PMMA straight-through MC array plate was used to produce water-in-oil (W/O) emulsions. Monodisperse W/O emulsions with average droplet diameters of approximately 25 μm and a minimum coefficient of variation of 3.2% were produced via a hydrophobic PMMA straight-through MC array. The PMMA straight-through MC array plate also produced monodisperse W/O emulsions at droplet production rates of up to 1.7 × 104/s. The PMMA straight-through MC array plates developed in this work are expected to expand the application field of emulsification using straight-through MC array plates, which have previously been made of single-crystal silicon.  相似文献   
7.
This article proposes a function for color information detection using genetic programming (GP). In image-processing, object detection is one of the important processes. In cases where the object has a complex color domain, detection becomes more difficult. We generated a detection function for a complex color domain by using GP. The detection function deals with one pixel of an input image, and it obtains an output image by processing for all pixels. We aimed at a reduction in the time taken by a human to consider an image-processing system design. We applied the generation of GP to detect a target color region in actual images. The results show that the detection function has sufficient ability for these detections.  相似文献   
8.
In this article, a new desktop orthogonal-type robot, which has the capacity of stick-slip motion control based on cutter location data, is presented for lapping small metallic molds with a curved surface. The robot consists of three single-axis devices with a high position resolution of 1 μm. A thin wooden stick tool with a ball-end shape is attached to the tip of the z-axis. In order to improve the lapping performance, a novel stick-slip motion control method is developed in the control system. The small stick-slip motion is orthogonally generated in the direction of the tool’s movement. The effectiveness of stick-slip motion control is examined through an actual lapping test of an LED lens cavity.  相似文献   
9.
Tree is a data structure used to express various objects such as semistructured data and genes. When objects are represented as trees, computing tree similarity is essential for pattern recognition and retrieval. This paper considers the noisy subsequence tree recognition problem whose purpose is to recognize the original tree, given its noisy subsequence tree. Previous research on this problem relied on constrained tree edit distance to measure the dissimilarity. However, the number of relabelings must be predetermined to compute it. This paper proposes a new dissimilarity measure for this problem. Our dissimilarity measure is obtained by counting the node edit operations included in the unit‐cost tree edit distance that contribute to the matching of node labels. The number of relabelings need not be specified to compute our dissimilarity measure. Moreover, our measure achieves more accurate recognition performance and faster execution speed than the constrained tree edit distance. Our measure is also useful to solve the tree inclusion problem which is the problem of deciding whether a tree includes another tree and shows the extent of approximate tree inclusion when a tree incompletely includes another tree. © 2011 Wiley Periodicals, Inc.  相似文献   
10.
This paper presents the design and control of a novel assistive robotic walker that we call “JAIST active robotic walker (JARoW)”. JARoW is developed to provide potential users with sufficient ambulatory capability in an efficient, cost-effective way. Specifically, our focus is placed on how to allow easier maneuverability by creating a natural interface between the user and JARoW. For the purpose, we develop a rotating infrared sensor to detect the user’s lower limb movement. The implementation details of the JARoW control algorithms based on the sensor measurements are explained, and the effectiveness of the proposed algorithms is verified through experiments. Our results confirmed that JARoW can autonomously adjust its motion direction and velocity according to the user’s walking behavior without requiring any additional user effort.  相似文献   
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