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21.
Yukihiro Koda Ichi Kanaya Kosuke Sato 《国际自动化与计算杂志》2007,4(1):14-17
A large number of 3D models are created on computers and available for networks. Some content-based retrieval technologies are indispensable to find out particular data from such anonymous datasets. Though several shape retrieval technologies have been developed, little attention has been given to the points on human's sense and impression (as known as Kansei) in the conventional techniques, In this paper, the authors propose a novel method of shape retrieval based on shape impression of human's Kansei. The key to the method is the Gaussian curvature distribution from 3D models as features for shape retrieval. Then it classifies the 3D models by extracted feature and measures similarity among models in storage. 相似文献
22.
Yuto Nishikawa 《Advanced Robotics》2019,33(12):567-575
This study aims to investigate the application of temperature gradient between the ground and the air to the locomotion of soft robot. Soft robots attract attention due to its flexible adaptability and safety to the real environment in recent years. Although many soft robots are soft themselves, they require hard material as an external device such as air compressors and external power supplies for driving. To solve the problem, some authors reported an autonomous driving robot composed of a completely flexible material using gas generation by a chemical change of hydrogen peroxide solution. However, as the driving system utilizes a chemical reaction, its driving time is relatively short. On the contrary, the proposed robot moves without electricity and any external devices such as air compressors and an electrical power supplies. It can move just on the ground using the temperature gradient between the ground and the air. In experiments, we developed some prototypes and confirmed that continuous movement could be achieved with the proposed model. 相似文献
23.
S Harino M Motokura N Nishikawa M Fukuda A Sasaoka JE Grunwald 《Canadian Metallurgical Quarterly》1994,117(3):302-307
We studied the ocular findings of two adult patients with the Eisenmenger's syndrome who had atrial septal defects that were diagnosed before the age of 10 years but not operated on and pulmonary hypertension. Both eyes of these patients showed microaneurysms, multiple small blot hemorrhages, or capillary dilation in the temporal peripheral fundus. Multiple microaneurysms and retinal collaterals were confirmed by fluorescein angiography. One of the patients developed bilateral rubeosis iridis with slow progression. These retinal lesions and the rubeosis iridis are probably related to chronic ocular ischemia caused by chronic systemic hypoxia. 相似文献
24.
N Sakaguchi M Yoshimura JM Hershman M Nishikawa M Inada 《Canadian Metallurgical Quarterly》1997,7(5):779-782
It is well known that human chorionic gonadotropin (hCG) is sometimes secreted from nontrophoblastic neoplasms. To elucidate the role of ectopic hCG, we investigated the effect of hCG produced from a papillary thyroid cancer cell line (B-CPAP cells) on stimulation and growth promotion of FRTL-5 rat thyroid cells. Ectopic hCG contained in the culture medium of B-CPAP cells was purified using gel filtration and bioassayed for thyrotropic activity in FRTL-5 cells. Addition of ectopic hCG (up to 5.2 x 10(4) IU/L) increased cyclic adenosine monophosphate (cAMP) accumulation and 3H-thymidine incorporation in FRTL-5 cells dose dependently. These effects were almost as potent as the stimulation induced by standard hCG CR-127. After the absorption of the ectopic hCG by anti-hCG-beta monoclonal antibody, the cAMP accumulation was significantly decreased. Analysis of ectopic hCG isoforms with different isoelectric points indicated the predominance of the acidic hCG isoform with isoelectric point (pI) 3.8-3.2 that is the major isoform of standard hCG. Basic isoforms (pI 5.7-5.3) with higher thyrotropic potency were also detected. These results indicate that the ectopic hCG secreted from papillary thyroid cancer cells possess intrinsic thyroid-stimulating and growth-promoting activity. The ectopic hCG may act as an autocrine-paracrine factor in nontrophoblastic neoplasms. 相似文献
25.
Harumi Sato Masahiko Shimoyama Taeko Kamiya Toru Amari Slobodan aic Toshio Ninomiya Heinz W. Siesler Yukihiro Ozaki 《应用聚合物科学杂志》2002,86(2):443-448
Raman spectra have been measured for pellets of five samples of high‐density polyethylene (HDPE), seven samples of low‐density polyethylene (LDPE), and six samples of linear low‐density polyethylene (LLDPE). The obtained Raman spectra have been compared to find out characteristic Raman bands of HDPE, LDPE, and LLDPE. Principal component analysis (PCA) was applied to the Raman spectra in the 1600–650 cm?1 region after multiplicative scatter correction (MSC) to discriminate the Raman spectra of the three different PE species. They are classified into three groups by a score plot of PCA factor 1 vs. 2. HDPE with high density and high crystallinity gives high scores on the factor 1 axis, while LDPE with low density and low crystallinity yields negative scores on the same axis. It seems that factor 1 reflects the density or crystallinity. A PC weight loadings plot for factor 1 shows six upward peaks corresponding to the bands arising from the crystalline parts or all‐trans ? (CH2)n? groups and seven downward peaks ascribed to the bands of the amorphous or anisotropic regions and those arising from the short branches. Partial least‐squares (PLS‐1) regression was applied to the Raman spectra after MSC to propose calibration models that predict the density, crystallinity, and melting points of the polyethylenes. The correlation coefficient was calculated to be 0.9941, 0.9800, and 0.9709 for the density, crystallinity, and melting point, respectively, and their root‐mean‐square error of cross validation (RMSECV) was found to be 0.0015, 3.3707, and 2.3745, respectively. The loadings plot of factor 2 for the prediction of melting point is largely different from those for the prediction of density and crystallinity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 443–448, 2002 相似文献
26.
Tsuyoshi Hagio Kazuo Kobayashi Hisayoshi Yoshida Hiroaki Yasunaga Hiroshi Nishikawa 《Journal of the American Ceramic Society》1989,72(8):1482-1484
Pressureless sintering of hexagonal boron nitride (BN) was performed using a powder activated by mechano-chemical treatments. Physical properties of the sintered BN bodies depend on the type of starting powder and the conditions of the treatments. The BN body, which was obtained at 2000°C using an appropriate activated powder, was 99 wt% pure and was excellent in mechanical and physical properties, in spite of its low density (1.64 g/cm3 ). 相似文献
27.
Tran Thi Ngoc Lan Rokuro Nishimura Yukihiro Satoh Masayuki Yokoi 《Corrosion Science》2005,47(4):1023-1038
The atmospheric corrosion of marble was evaluated in terms of SO2 concentration as air pollution and climatic factors such as rainfall, relative humidity, temperature and so on under the field exposure. Marble of calcite type (CaCO3) was exposed to outdoor atmospheric environment with and without a rain shelter at four test sites in the southern part of Vietnam for 3-month, 1- and 2-year periods from July 2001 to September 2003. The thickness loss of marble was investigated gravimetrically. X-ray diffraction and X-ray fluorescent methods were applied to study corrosion products on marble. The corrosion product of marble was only gypsum (CaSO4 · 2H2O) and was washed out by rain under the unsheltered exposure condition. It was found that the most substantial factors influencing the corrosion of marble were rainfall, SO2 concentration in the air and relative humidity. Based on the results obtained, we estimated the dose-response functions for the atmospheric corrosion of marble in the southern part of Vietnam. 相似文献
28.
Improvement in impact strength of modified cardanol‐bonded cellulose thermoplastic resin by adding modified silicones 下载免费PDF全文
The impact strength of cellulose diacetate (CDA) bonded with a modified cardanol (3‐pentadecylphenoxy acetic acid: PAA) was greatly improved up to 9 kJ/m2 by adding a relatively small amount of modified silicones while suppressing a decrease in bending strength. In our recent research, this thermoplastic resin (PAA‐bonded CDA) exhibited high rigidity, glass transition temperature, and water resistance. However, its impact strength was insufficient for use in durable products. Therefore, silicones modified with polyether, amino, and epoxy groups were investigated as possible ways to improve the impact strength. The results show that adding polyether‐modified silicone (polyether silicone) with moderate polarity relative to PAA‐bonded CDA resulted in shearing deformation greatly enhances its impact strength while maintaining other properties, including glass transition temperature (Tg), water resistance, and thermoplasticity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40366. 相似文献
29.
Goda Y Akiyama H Suyama E Takahashi S Kinjo J Nohara T Toyoda M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(6):339-347
Soyasaponins and isoflavones are main secondary metabolites in soybeans. In this report we compared the content of secondary metabolites between genetically modified (GM) and non-GM soybeans. Six cultivars/lines of GM and six cultivars/lines of non-GM soybeans were extracted with methanol. Each extract was partitioned with aqueous methanol and hexane and the aqueous methanol fraction was partially purified by HP-20 and LH-20 column chromatography to afford crude soyasaponin and isoflavone fractions. The main A-type soyasaponin, acetylsoyasaponin A1 (AcA1), and the main B-type soyasaponins, soyasaponins I and II (I and II), in the crude fractions were identified by LC/MS analyses with authentic samples. The main isoflavones, daidzin, genistin, daidzein and genistein (DI, GI, DE and GE), in the crude fractions were identified by LC photo-diode array analyses with authentic samples. The contents of AcA1, I and II in the crude soyasaponin fractions and those of DI, GI, DE and GE in the crude isoflavone fractions were analyzed by reversed-phase HPLC. The average contents (mg/100 g) of AcA1, I, II and total of B-type soyasaponins in GM soybeans were 36.4 +/- 24.2, 51.2 +/- 11.8, 26.4 +/- 7.6 and 77.7 +/- 18.5, respectively, and those in non-GM ones were 22.3 +/- 14.7, 46.3 +/- 17.8, 19.8 +/- 9.1 and 65.9 +/- 26.9, respectively. The average contents (mg/100 g) of DI, GI, DE, GE and total isoflavones in GM soybeans were 93.1 +/- 15.5, 121.8 +/- 19.4, 0.073 +/- 0.178, 0.320 +/- 0.082 and 215.3 +/- 33.3, respectively, and those in non-GM ones were 78.8 +/- 34.6, 106.7 +/- 28.3, 2.206 +/- 4.468, 0.822 +/- 0.754 and 188.5 +/- 26.7, respectively. There were no statistically significant differences in soyasaponin and isoflavone contents between GM and non-GM soybeans. Therefore, it was estimated that the GM soybeans are equivalent to the non-GM ones in terms of the composition of the main secondary metabolites. 相似文献
30.
A new wavelength interval selection procedure, moving window partial least-squares regression (MWPLSR), is proposed for multicomponent spectral analysis. This procedure builds a series of PLS models in a window that moves over the whole spectral region and then locates useful spectral intervals in terms of the least complexity of PLS models reaching a desired error level. Based on a proposed theory demonstrating the necessity of wavelength selection, it is shown that MWPLSR provides a viable approach to eliminate the extra variability generated by non-composition-related factors such as the perturbations in experimental conditions and physical properties of samples. A salient advantage of MWPLSR is that the calibration model is very stable against the interference from non-composition-related factors. Moreover, the selection of spectral intervals in terms of the least model complexity enables the reduction of the size of a calibration sample set in calibration modeling. Two strategies are suggested for coupling the MWPLSR procedure with PLS for multicomponent spectral analysis: One is the inclusion of all selected intervals to develop a PLS calibration model, and the other is the combination of the PLS models built separately in each interval. The combination of multiple PLS models offers a novel potential tool for improving the performance of individual models. The proposed procedures are evaluated using two open-path Fourier transform infrared data sets and one near-infrared data set, each having different noise characteristics. The results reveal that the proposed procedures are very promising for vibrational spectroscopy-based multicomponent analyses and give much better prediction than the full-spectrum PLS modeling. 相似文献