http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Nozawa, Takaya,Yoon, Sung-Chul,Maeda, Keiichi,Kozasa, Takashi,Nomoto, Ken'ichi,Langer, Norbert University of Chicago Press for the American Astro 2014 ASTROPHYSICAL JOURNAL LETTERS - Vol.787 No.2
We investigate the formation of dust in a stellar wind during the red-supergiant (RSG) phase of a very massive Population III star with a zero-age main sequence mass of 500 M-circle dot. We show that, in a carbon-rich wind with a constant velocity, carbon grains can form with a lognormal-like size distribution, and that all of the carbon available for dust formation finally condenses into dust for wide ranges of the mass-loss rate ((0.1-3) x 10(-3) M-circle dot yr(-1)) and wind velocity (1-100 km s(-1)). We also find that the acceleration of the wind, driven by newly formed dust, suppresses the grain growth but still allows more than half of the gas-phase carbon to finally be locked up in dust grains. These results indicate that, at most, 1.7 M-circle dot of carbon grains can form during the RSG phase of 500 M-circle dot Population III stars. Such a high dust yield could place very massive primordial stars as important sources of dust at the very early epoch of the universe if the initial mass function of Population III stars was top-heavy. We also briefly discuss a new formation scenario of carbon-rich ultra-metal-poor stars, considering feedback from very massive Population III stars.
Nozawa, Tatsuhiro,Miyaguchi, Yuki,Hida, Yusuke,Koyanagi, Kaoru,Yokoyama, Ryuichi,Shirai, Goro 대한전기학회 2012 The Journal of International Council on Electrical Vol.2 No.1
This paper presents the effectiveness evaluation approach of demand side management (dema nd control) for frequency regulation in regional power networks (so called Cluster-oriented networks). The analytical model of the frequency fluctuation for a three-cluster interconnected network model was developed with MATLAB/SIMULINK. The control method is similar to the conventional TBC (Tie Line Bias Control) widely used in power grids. In order to maintain the quality of frequency, Battery Energy Storage Systems (BESS) and controllable loads such as heat pumps installed in the customer side will play an effective role in clusters. By the results of conducted simulations, it shows that the proposed new frequency regulation scheme by utilizing controllable loads such as battery charges and heat pumps retains effectiveness to suppress frequency deviation when a large amount of natural renewable energy is installed in the regional cluster-oriented networks.
Low-Power 12-bit 160-MS/s Pipeline A/D Converters
Mai Nozawa,Daisuke Kurose,Takeshi Ueno,Tetsuro Itakura 대한전자공학회 2008 ITC-CSCC :International Technical Conference on Ci Vol.2008 No.7
Low-power 12-bit 160-MS/s pipeline A/D converters are designed for wireless receivers. Instead of using ultra-deep submicron devices of low supply voltage, we employ analog-option devices that operate at supply voltage of 2.5V in a 90-㎚ CMOS process. To achieve lower power dissipation, an I/Q amplifier sharing technique is employed. Furthermore, charge transfer level shifters are proposed in S/H circuits and MDACs for realizing class-AB operation. The area is 1.1㎟, the simulated power dissipation is 75㎽/channel and the simulated ENOB is 11.15bit.
Discrete Modeling of Patellar-Tendon-Reflexes As Logistic Phenomena
Takashi Nozawa,Noriyuki Hori,Naotaka Mamizuka 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10
The present paper proposes a logistic model to represent patellar-tendon-reflexes (PTR) from the release-angle of the tapping-hammer to the peak angular-speed of the knee joint. The experimental data obtained are discrete in nature and, thus, they are modeled as a discrete system. However, the model is formulated such that parameters of the underlying continuous model are directly obtained so that the discrete results can be related to continuous counterpart with ease. From the observation of PTR data, it was noticed that they resemble well some of the features exhibited by a system whose characteristics are governed by a logistic equation. For these reasons, a technique developed recently for exact time-discretization of nonlinear systems was applied to this non-temporal discrete system. A discrete logistic model was identified from the experimental data obtained from human reflexes. Furthermore, a method is presented to determine an appropriate initial condition to reproduce the data curve using the identified model. The overall scheme was found to give results that were closer to actual data than the popular forward difference method, even with a very large discrete interval. This is important since the modeling can be achieved using a small number of tapping on the patients.
Indoor Human Navigation System on Smartphones using View-Based Navigation
Mitsuaki Nozawa,Yoshinobu Hagiwara,Yongwoon Choi 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10
We present a new human navigation system on smartphones for indoor environments. The conventional systems have required specific positioning infrastructures installed in buildings. In contrast, the proposed system is not to need such requirements because it can determine the position of a user by image matching to process the images from a smartphone camera indoors like a certain corridor. Although a number of personal positioning methods based on image processing have been proposed, it has been difficult in processing cost to apply them just like that to the proposed system. From this point of view, we have focused on the view-based navigation which has been developed as an indoor positioning method for robots due to its simple algorithm by only one monocular camera. By devising the techniques for applying this view-based navigation to a smartphone, we can visually provide the user having a smartphone the positional and directional information to a destination. This paper describes the algorithm of the view-based navigation speeded up for smartphones and shows experimental results for human navigation performed with usually walking in an indoor corridor.