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81.
The activity of CaO in the CaO-ZrO2 system has been measured at 1572 to 1877 K with a Galvanic cell composed of 4CaO ? P2O5 as the solid electrolyte. The activity ZrO2 was calculated from the activity of CaO by integrating the Gibbs-Duhem relation. From the activities of CaO and ZrO2, the standard Gibbs free energy of formation of CaO ? ZrO2 was determined as follows: ΔG f 0 /J mol?1 = -25,200 (±150) - 17.58 (±0.085)T (1633 to 1873 K) 相似文献
82.
Goran T. Vladisavljevi? Isao Kobayashi Mitsutoshi Nakajima 《Microfluidics and nanofluidics》2011,10(6):1199-1209
Uniformly sized droplets of soybean oil, MCT (medium-chain fatty acid triglyceride) oil and n-tetradecane with a Sauter mean diameter of d
3,2 = 26–35 μm and a distribution span of 0.21–0.25 have been produced at high throughputs using a 24 × 24 mm silicon microchannel
plate consisting of 23,348 asymmetric channels fabricated by photolithography and deep reactive ion etching. Each channel
consisted of a 10-μm diameter straight-through micro-hole with a length of 70 μm and a 50 × 10 μm micro-slot with a depth
of 30 μm at the outlet of each channel. The maximum dispersed phase flux for monodisperse emulsion generation increased with
decreasing dispersed phase viscosity and ranged from over 120 L m−2 h−1 for soybean oil to 2,700 L m−2 h−1 for n-tetradecane. The droplet generation frequency showed significant channel to channel variations and increased with decreasing
viscosity of the dispersed phase. For n-tetradecane, the maximum mean droplet generation frequency was 250 Hz per single active channel, corresponding to the overall
throughput in the device of 3.2 million droplets per second. The proportion of active channels at high throughputs approached
100% for soybean oil and MCT oil, and 50% for n-tetradecane. The agreement between the experimental and CFD (Computational Fluid Dynamics) results was excellent for soybean
oil and the poorest for n-tetradecane. 相似文献
83.
Kazuhiro Hotta Author Vitae 《Pattern recognition》2010,43(3):906-913
Kernel-based methods are effective for object detection and recognition. However, the computational cost when using kernel functions is high, except when using linear kernels. To realize fast and robust recognition, we apply normalized linear kernels to local regions of a recognition target, and the kernel outputs are integrated by summation. This kernel is referred to as a local normalized linear summation kernel. Here, we show that kernel-based methods that employ local normalized linear summation kernels can be computed by a linear kernel of local normalized features. Thus, the computational cost of the kernel is nearly the same as that of a linear kernel and much lower than that of radial basis function (RBF) and polynomial kernels. The effectiveness of the proposed method is evaluated in face detection and recognition problems, and we confirm that our kernel provides higher accuracy with lower computational cost than RBF and polynomial kernels. In addition, our kernel is also robust to partial occlusion and shadows on faces since it is based on the summation of local kernels. 相似文献
84.
Yuichiro Ezoe Ikuyuki Mitsuishi Utako Takagi Masaki Koshiishi Kazuhisa Mitsuda Noriko Y. Yamasaki Takaya Ohashi Fumiki Kato Susumu Sugiyama Raul E. Riveros Hitomi Yamaguchi Shinya Fujihira Yoshiaki Kanamori Kohei Morishita Kazuo Nakajima Ryutaro Maeda 《Microsystem Technologies》2010,16(8-9):1633-1641
We are developing novel ultra light-weight and high-resolution X-ray micro pore optics for space X-ray telescopes. In our method, curvilinear micro pore structures are firstly fabricated by silicon deep reactive ion etching (DRIE) or X-ray LIGA processes. Secondly, side walls of the micro structures are smoothed by magnetic field assisted finishing and/or hydrogen annealing techniques for high reflectivity mirrors. Thirdly, to focus parallel X-ray lights from astronomical objects, these structures are elastically or plastically bent into a spherical shape. Fourthly, the bent structures are stacked to form a multi-stage X-ray telescope. In this paper, we report on fabrication and X-ray reflection tests of silicon and nickel X-ray mirrors using the DRIE and LIGA processes, respectively. For the first time, X-ray reflections were confirmed on both of the mirrors. Estimated rms roughnesses were 5 nm and 3 nm for the silicon and nickel mirrors, respectively. 相似文献
85.
A portable toolkit for supporting end-user personalization and control in context-aware applications 总被引:1,自引:0,他引:1
Fahim Kawsar Kaori Fujinami Tatsuo Nakajima Jong Hyuk Park Sang-Soo Yeo 《Multimedia Tools and Applications》2010,47(3):409-432
A context-aware application in the pervasive computing environment provides intuitive user centric services using implicit
context cues. Personalization and control are important issues for this class of application as they enable end-users to understand
and configure the behavior of an application. However most development efforts for building context-aware applications focus
on the sensor fusion and machine learning algorithms to generate and distribute context cues that drive the application with
little emphasis on user-centric issues. We argue that, to elevate user experiences with context-aware applications, it is
very important to address these personalization and control issues at the system interface level in parallel to context centric
design. Towards this direction, we present Persona, a toolkit that provides support for extending context-aware applications with end-user personalization and control features.
Specifically, Persona exposes a few application programming interfaces that abstract end-user customization and control mechanisms
and enables developers to integrate these user-centric aspects with rest of the application seamlessly. There are two primary
advantages of Persona. First, it can be used with various existing middlewares as a ready-to-use plug-in to build customizable
and controllable context-aware applications. Second, existing context-aware applications can easily be augmented to provide
end-user personalization and control support. In this paper, we discuss the design and implementation of Persona and demonstrate
its usefulness through the development and augmentation of a range of common context-aware applications. 相似文献
86.
This paper presents an algebraic approach to polynomial spectral factorization, an important mathematical tool in signal processing and control. The approach exploits an intriguing relationship between the theory of Gröbner bases and polynomial spectral factorization which can be observed through the sum of roots, and allows us to perform polynomial spectral factorization in the presence of real parameters. It is discussed that parametric polynomial spectral factorization enables us to express quantities such as the optimal cost in terms of parameters and the sum of roots. Furthermore an optimization method over parameters is suggested that makes use of the results from parametric polynomial spectral factorization and also employs two quantifier elimination techniques. This proposed approach is demonstrated in a numerical example of a particular control problem. 相似文献
87.
Shiro Kumano Kazuhiro Otsuka Junji Yamato Eisaku Maeda Yoichi Sato 《International Journal of Computer Vision》2009,83(2):178-194
In this paper, we propose a method for pose-invariant facial expression recognition from monocular video sequences. The advantage
of our method is that, unlike existing methods, our method uses a simple model, called the variable-intensity template, for
describing different facial expressions. This makes it possible to prepare a model for each person with very little time and
effort. Variable-intensity templates describe how the intensities of multiple points, defined in the vicinity of facial parts,
vary with different facial expressions. By using this model in the framework of a particle filter, our method is capable of
estimating facial poses and expressions simultaneously. Experiments demonstrate the effectiveness of our method. A recognition
rate of over 90% is achieved for all facial orientations, horizontal, vertical, and in-plane, in the range of ±40 degrees,
±20 degrees, and ±40 degrees from the frontal view, respectively.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
88.
Takashi Soga Akihiro Musa Koki Okabe Kazuhiko Komatsu Ryusuke Egawa Hiroyuki Takizawa Hiroaki Kobayashi Shun Takahashi Daisuke Sasaki Kazuhiro Nakahashi 《Computers & Fluids》2011,45(1):215-221
The building-cube method (BCM) is a new generation algorithm for CFD simulations. The basic idea of BCM is to simplify the algorithm in all stages of flow computation to achieve large-scale simulations. Calculation of a pressure field using the Successive Over Relaxation (SOR) method consumes most of the total execution time required for BCM. In this paper, effective implementations on modern vector and scalar processors are investigated. NEC SX-9 and Intel Nehalem-EX are the latest vector and scalar processors. Those processors have much higher peak performances than their previous-generation processors. However, their memory bandwidth improvement cannot catch up with the performance improvement of processors. This is the so-called memory wall problem. In our paper, we discuss optimization techniques for implementation of the SOR method based on architectural characteristics of these modern processors, and evaluate their effects on the sustained performances of these processors for BCM. 相似文献
89.
Yoshihiro Nakajima Mitsuhisa Sato Yoshiaki Aida Taisuke Boku Franck Cappello 《Journal of Grid Computing》2008,6(2):141-157
We present a framework for a parallel programming model by remote procedure calls, which bridge large-scale computing resource
pools managed by multiple Grid-enabled job scheduling systems. With this system, the user can exploit not only remote servers
and clusters, but also the computing resources provided by Grid-enabled job scheduling systems located on different sites.
This framework requires a Grid remote procedure call (RPC) system to decouple the computation in a remote node from the Grid
RPC mechanism and uses document-based communication rather than connection-based communication. We implemented the proposed
framework as an extension of the OmniRPC system, which is a Grid RPC system for parallel programming. We designed a general
interface to easily adapt the OmniRPC system to various Grid-enabled job scheduling systems, including XtremWeb, CyberGRIP,
Condor and Grid Engine. We show the preliminary performance of these implementations using a phylogenetic application. We
found that the proposed system can achieve approximately the same performance as OmniRPC and can handle interruptions in worker
programs on remote nodes.
Yoshihiro Nakajima is a Research Fellow of the Japan Society for the Promotion of Science 相似文献
90.
Isao Kobayashi Yoshihiro Wada Kunihiko Uemura Mitsutoshi Nakajima 《Microfluidics and nanofluidics》2008,5(5):677-687
This study investigated the generation of oil drops using new symmetric and asymmetric through-hole-array devices made of
stainless steel. The through-hole-array devices were built by piling up six stainless-steel plates, each having circular micro-holes
with a diameter of 300 or 500 μm or micro-slots with a shorter line of 300 or 500 μm. Drops were generated by injecting a
dispersed phase (refined soybean oil) via the through-hole array into a compartment filled with a continuous phase (Milli-Q
water solution containing one of two emulsifiers). The drop detachment from symmetric and asymmetric through holes was observed
in real time and analyzed. Uniform oil drops with average diameters of 1.0–4.1 mm and coefficients of variation of typically
less than 6% were generated using symmetric and asymmetric through-hole-array devices. The resultant drop diameters for asymmetric
through-hole arrays were significantly smaller than those for symmetric through-hole arrays. This paper also discusses experimental
results regarding the effects of the microstructure, the dimensions of the through holes, and the type of emulsifier on drop
generation and the resultant drop diameter. 相似文献