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1.
Takeshi Kondo Hiroyuki Ito Kazuhide Kusakabe Kazuhiro Ohkawa Kensuke Honda Yasuaki Einaga Akira Fujishima Takeshi Kawai 《Diamond and Related Materials》2008,17(1):48-54
The effect of CF4 plasma etching on diamond surfaces, with respect to treatment time, was investigated using scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and electrochemical measurements. SEM observations and Raman spectra indicated an increase in surface roughening on a scale of 10–20 nm, and an increase in crystal defect density was apparent with treatment time in the range of 10 s to 30 min. In contrast, alteration of the diamond surface terminations from oxygen to fluorine was found to be rather rapid, with saturation of the F/C atomic ratio estimated from XPS analysis after treatment durations of 1 min and more. The redox kinetics of Fe(CN)63−/4− was also found to be significantly modified after 10 s of CF4 plasma treatment. This behavior shows that C–F terminations predominantly affect the redox kinetics compared to the effect on the surface roughness and crystal defects. The double-layer capacitance (Cdl) of the electrolyte/CF4 plasma-treated boron-doped diamond interface was found to show a minimum value at 1 min of treatment. These results indicate that a short-duration CF4 plasma treatment is effective for the fabrication of fluorine-terminated diamond surfaces without undesirable surface damage. 相似文献
2.
Koji Kamei Kunihiko Fujita Eva Jettmar Sen Yoshida Kazuhiro Kuwabara 《Interacting with computers》2002,14(6):438-759
In this paper, we present and discuss Community Organizer, a system designed to support network communities. The main characteristic of Community Organizer is the use of spatial representations for the relationships among community members including the communications exchanged among these members. These spatial representations reflect the degree of closeness of interests and concerns among the members, and are intended to provide users with clues on how to form network communities. In order to investigate the effectiveness of the proposed spatial representations, we conducted experiments with two different versions of the software. One version offered meaningful spatial representations while the other version did not. The subjects who used the former software version felt a greater sense of ‘community’, enjoyed using the software more, and actively used it longer than the subjects using the latter software version (control condition). These results indicated that the proposed spatial representations are effective in supporting network community formation. 相似文献
3.
4.
Lipid-Lowering Effect of Eriocitrin, the Main Flavonoid in Lemon Fruit, in Rats on a High-Fat and High-Cholesterol Diet 总被引:2,自引:0,他引:2
Yoshiaki Miyake Eriko Suzuki Satoko Ohya Syuichi Fukumoto Masanori Hiramitsu Kazuhiro Sakaida Toshihiko Osawa Yukio Furuichi 《Journal of food science》2006,71(9):S633-S637
ABSTRACT: Eriocitrin (eriodictyol 7- O -β-rutinoside) is the main flavonoid in lemon fruit. In this study, eriocitrin was investigated for its lowering effect on serum and hepatic lipids in high-fat and high-cholesterol fed rats. Rats in the control group ( N = 6) were fed a 20% lard and 1% cholesterol diet for 21 d, and rats in the 0.35% eriocitrin group ( N = 6) and 0.70% eriocitrin group ( N = 6) were fed a diet supplemented with eriocitrin 0.35% and 0.70%, respectively. The content of hepatic total cholesterol and triglyceride in the eriocitrin group was no different from that of the control group. The total cholesterol, VLDL+LDL, triglyceride, and phospholipid in the serum of the 0.35% eriocitrin group showed significantly lower concentrations than the control group ( P < 0.05), although there was no difference in the HDL concentrations among the groups. The lowering effect of eriocitrin for serum total cholesterol was thought to be caused by a decrease in VLDL+LDL. The 0.35% eriocitrin group was shown to have a significant increase in excretion of fecal bile acid ( P < 0.05) and a tendency for enhanced hepatic m-RNA levels of LDL receptor in comparison with the control group. 相似文献
5.
In this paper we analyze the average-case performance of the Modified Harmonic algorithm for on-line bin packing. We first analyze the average-case performance for arbitrary distribution of item sizes over (0,1]. This analysis is based on the following result. Letf
1 andf
2 be two linear combinations of random variables {N
i
}
i=1
k
where theN
i
's have a joint multinomial distribution for eachn=
i=1
k
,N
i
. LetE(f
1) O andE(f
2) 0. Then limn
E(max(f
1,f
2
))/n = lim
n
max(E(f
1),E(f
2))/n. We then consider the special case when the item sizes are uniformly distributed over (0,1]. For specific values of the parameters, the Modified Harmonic algorithm turns out to be better than the other two linear-time on-line algorithms—Next Fit and Harmonic—in both the worst case as well as the average case. We also obtain optimal values for the parameters of the algorithm from the average-case standpoint. For these values of the parameters, the average-case performance ratio is less than 1.19. This compares well with the performance ratios 1.333. and 1.2865. of the Next Fit algorithm and the Harmonic algorithm, respectively. 相似文献
6.
In this paper we analyze the average-case performance of the Modified Harmonic algorithm for on-line bin packing. We first analyze the average-case performance for arbitrary distribution of item sizes over (0,1]. This analysis is based on the following result. Letf 1 andf 2 be two linear combinations of random variables {N i } i=1 k where theN i 's have a joint multinomial distribution for eachn=σ i=1 k ,N i . LetE(f 1) ≠ O andE(f 2)≠ 0. Then limn →∞E(max(f 1,f 2 ))/n = lim n →∞ max(E(f 1),E(f 2))/n. We then consider the special case when the item sizes are uniformly distributed over (0,1]. For specific values of the parameters, the Modified Harmonic algorithm turns out to be better than the other two linear-time on-line algorithms—Next Fit and Harmonic—in both the worst case as well as the average case. We also obtain optimal values for the parameters of the algorithm from the average-case standpoint. For these values of the parameters, the average-case performance ratio is less than 1.19. This compares well with the performance ratios 1.333. and 1.2865. of the Next Fit algorithm and the Harmonic algorithm, respectively. 相似文献
7.
Numerical solutions of the singular integral equations in the crack analysis using the body force method 总被引:1,自引:1,他引:0
In this paper, numerical solutions of the singular integral equations of the body force method in the crack problems are discussed. The stress fields induced by two kinds of displacement discontinuity are used as fundamental solutions. Then, the problem is formulated as a hypersingular integral equation with the singularity of the form r
2. In the numerical calculation, two kinds of unknown functions are approximated by the products of the fundamental density function and the Chebyshev polynomials. As examples, the stress intensity factors of the oblique edge crack, kinked crack, branched crack and zig-zag crack are analyzed. The calculation shows that the present method gives accurate results even for the extremely oblique edge crack and kinked crack with extremely short bend which has been difficult to analyze by the previous method using the approximation by the products of the fundamental density function and the stepped functions etc. 相似文献
8.
Recent laboratory research has indicated that coal fly ash derived from subbituminous and bituminous type coals is a sink for atmospheric mercury (Hg), however lignite-based ash was found to emit Hg to the air. Solids collected from systems with components that enhance Hg removal (i.e. activated carbon injection (ACI), flue gas desulfurization (FGD), and selective catalytic reduction (SCR) or selective non-catalytic reduction (SNCR)) may have higher Hg concentrations and therefore a higher potential for Hg release. For this study we investigated the potential for Hg release to the air and water from coal combustion products (CCPs) collected from coal-fired units with FGD equipment, SCR and SNCR equipment, and sorbent injection for Hg removal. In the laboratory study, most dry samples acted as sinks for atmospheric Hg in the dark at 25 °C. When exposed to light or increased temperature (45 °C), deposition of Hg to the fly ash substrates in most cases continued but decreased. Wet FGD samples emitted Hg. However, they became a sink for atmospheric Hg or exhibited low Hg emission rates when dried. Mercury flux in the dark at 25 °C was correlated with fly ash carbon content (LOI). Most liquid extracts derived using the synthetic precipitation leaching procedure (SPLP EPA method 1312) had very low Hg concentrations (<13 ng/l). 相似文献
9.
The improvement of safety and dependability in systems that physically interact with humans requires investigation with respect to the possible states of the user’s motion and an attempt to recognize these states. In this study, we propose a method for real-time visual state classification of a user with a walking support system. The visual features are extracted using principal component analysis and classification is performed by hidden Markov models, both for real-time fall detection (one-class classification) and real-time state recognition (multi-class classification). The algorithms are used in experiments with a passive-type walker robot called “RT Walker” equipped with servo brakes and a depth sensor (Microsoft Kinect). The experiments are performed with 10 subjects, including an experienced physiotherapist who can imitate the walking pattern of the elderly and people with disabilities. The results of the state classification can be used to improve fall-prevention control algorithms for walking support systems. The proposed method can also be used for other vision-based classification applications, which require real-time abnormality detection or state recognition. 相似文献
10.
Amr Almaddah Sadi Vural Yasushi Mae Kenichi Ohara Tatsuo Arai 《Machine Vision and Applications》2014,25(4):845-857
As part of the face recognition task in a robust security system, we propose a novel approach for the illumination recovery of faces with cast shadows and specularities. Given a single 2D face image, we relight the face object by extracting the nine spherical harmonic bases and the face spherical illumination coefficients by using the face spherical spaces properties. First, an illumination training database is generated by computing the properties of the spherical spaces out of face albedo and normal values estimated from 2D training images. The training database is then discriminately divided into two directions in terms of the illumination quality and light direction of each image. Based on the generated multi-level illumination discriminative training space, we analyze the target face pixels and compare them with the appropriate training subspace using pre-generated tiles. When designing the framework, practical real-time processing speed and small image size were considered. In contrast to other approaches, our technique requires neither 3D face models nor restricted illumination conditions for the training process. Furthermore, the proposed approach uses one single face image to estimate the face albedo and face spherical spaces. In this work, we also provide the results of a series of experiments performed on publicly available databases to show the significant improvements in the face recognition rates. 相似文献