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141.
In this paper, we design a user-support system for vision information using smart phones. When the user takes a picture of a target using the smart phone camera, our system can recognize the image of the target and recommend a suitable service to the user. The system executes simple image analysis and determines a suitable service for the target image. The simple image analysis can extract 13 parameters (e.g., color information (RGB), number of intersections, depth of intersection, line width, and line depth). We use machine learning to classify the parameters into each service. In our research, we use a Support Vector Machine as a learning machine tool. Our system design provides user support for several services such as translation, barcode readers, and diagnosis of skin images and demonstrates the effectiveness of our research. 相似文献
142.
Yu Nagata Masaya Minagawa Shosei Hisatomi Yuki Tsunazawa Kyoko Okuyama Motonori Iwamoto Yasuyoshi Sekine Chiharu Tokoro 《Advanced Powder Technology》2019,30(5):1034-1042
A bead mill is commonly used to produce nanomaterials. The design of the bead mill rotor is an important factor in efficient nanomaterial production to avoid re-agglomeration. We investigated the effect of bead-mill rotor shape on the dispersion state using experimental tests and the discrete-element method (DEM) coupled with computational fluid dynamics (CFD) simulations. Experimental results using TiO2 in the bead mill showed that the high rotor rotation speed caused TiO2 particles re-agglomeration, and a sharp particle-size distribution was obtained by dispersion with a mill with a wide gap between the rotor and the chamber. To evaluate the dispersion performance, bead collisions were analyzed using the DEM-CFD simulation. The simulation results indicated that an increase in bead-collision energy lead to damage of the TiO2 primary particles and re-agglomeration at a high rotation speed. A uniform dispersion was achieved when the frequency of high-energy collision between the particle and wall decreased and a small standard deviation of the collision energy frequency was obtained by the mill with a wide gap. These simulation results correlate with the experimental results. Therefore, this study shows that the DEM-CFD simulation could contribute to an appropriate rotor design for uniform dispersion. 相似文献
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H. Nishiyama K. Tsuri H. Shimizu K. Katagiri H. Takana Y. Nakano 《International Journal of Heat and Mass Transfer》2009,52(7-8):1778-1785
Important operating parameters, temperature characteristics and radical production in an air plasma flow generated by a low-power pulsed arc discharge were experimentally clarified for lean combustion enhancement and surface treatment. Furthermore, the time-dependent thermofluid field downstream from the torch was also clarified numerically and the downstream temperature well agreed with experimental data. Finally, the time evolution of production and decay of the chemical species in air plasma were clarified numerically under a high electric field. 相似文献
146.
Nico A. Gaida Steeve Gréaux Yoshio Kono Hiroaki Ohfuji Hideharu Kuwahara Norimasa Nishiyama Oliver Beermann Takuya Sasaki Ken Niwa Masashi Hasegawa 《Journal of the American Ceramic Society》2021,104(1):635-644
Material properties, such as elasticity data at wide-ranging conditions of pressure and temperature, attract increasing attention for material and earth sciences. In particular, polycrystalline ceramics for next-generation photonic applications are nowadays fabricated by advanced syntheses techniques operating under elevated pressures and temperatures. Herein, the elastic properties of a synthetic transparent and reinforced aluminosilicate nanoceramic composed of triclinic kyanite with minor amounts of trigonal α-alumina crystals are investigated using in situ synchrotron X-ray diffraction and ultrasonic techniques at high-pressure (up to 11 GPa) and high-temperature (300-1500 K) conditions. This not only enables the determination of the equation of state (EoS) parameters by applying the pressure-volume-temperature (P-V-T) data to the high-temperature Birch-Murnaghan EoS but also yields the elastic moduli together with their P and T derivatives from the fit of the compressional and shear wave velocities to a finite strain EoS: KS0,300 = 186(2) GPa, K′S0,300 = 7.2(6), (∂KS0,300/∂T)P = −0.023(2) GPa K−1, G0,300 = 125(1) GPa G′0,300 = 2.3(2), (∂G0,300/∂T)P = −0.017(1) GPa K−1. On the basis of our acquired results, we propose to predict the elastic moduli of aluminosilicate ceramics by a linear function of the ratio of AlO6 octahedra and SiO4 tetrahedra within the constituting phases. 相似文献
147.
Kotaro Nishiyama Dr. Norikazu Ichihashi Dr. Tomoaki Matsuura Dr. Yasuaki Kazuta Prof. Tetsuya Yomo 《Chembiochem : a European journal of chemical biology》2012,13(18):2701-2706
Genome size is considered one of the limiting factors for the replication of primitive life forms. However, the relationship between genome size and replication efficiency has not been tested experimentally. In this study, we examined the effect of genome size on genome replication by using an artificial cell model: a self‐replicating RNA genome encapsulated in a liposome. For the reduced genome size we used α‐complementation of the lacZ gene. We first characterized α‐complementation in the purified translation system and then applied α‐complementation to the genome replication system. The reduction in the genome size together with the addition of ω‐fragment increased the replication efficiency approximately eightfold. This result provides experimental evidence that genome size can be a limiting factor for primitive self‐replication systems; it also implies that this artificial cell model could be a useful experimental model to identify possible mechanisms of genome enlargement. 相似文献
148.
In recent years, the ability to manage schedules using a mobile device equipped with a touch panel has increased. However, when one wishes to add a new event to the schedule book while taking into account the transit time for an existing event, it is necessary to switch to another application or website. In this study, we design a system that determines automatically whether the new event can be added. If it is impossible to add the event, the system proposes a time range in which events can be added. 相似文献
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150.
Nur Suhaili Abd Aziz Tomoya Nishiyama Nurul Izni Rusli Mohamad Rusop Mahmood Kanji Yasui Abdul Manaf Hashim 《Nanoscale research letters》2014,9(1):337
A seedless growth of zinc oxide (ZnO) structures on multilayer (ML) graphene by electrochemical deposition without any pre-deposited ZnO seed layer or metal catalyst was studied. A high density of a mixture of vertically aligned/non-aligned ZnO rods and flower-shaped structures was obtained. ML graphene seems to generate the formation of flower-shaped structures due to the stacking boundaries. The nucleation of ZnO seems to be promoted at the stacking edges of ML graphene with the increase of applied current density, resulting in the formation of flower-shaped structures. The diameters of the rods/flower-shaped structures also increase with the applied current density. ZnO rods/flower-shaped structures with high aspect ratio over 5.0 and good crystallinity were obtained at the applied current densities of −0.5 and −1.0 mA/cm2. The growth mechanism was proposed. The growth involves the formation of ZnO nucleation below 80°C and the enhancement of the growth of vertically non-aligned rods and flower-shaped structures at 80°C. Such ZnO/graphene hybrid structure provides several potential applications in sensing devices. 相似文献