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71.
Izumi Satake John H. XinTu Tianming Aran HansuebsaiKenji Ando Tetsuya SatoKanji Kajiwara Seiji Ohsawa 《Progress in Organic Coatings》2011,72(3):528-540
This article compares color assessments of automotive exteriors at four locations in China, Thailand and Japan. This study employed painted panels of twelve colors, thirty sensory words and fifteen pairs of emotion variables. It also used reference figures of nine cars that included four styling categories, namely sedans, compacts, sport utility vehicles and sports cars. The results of like-dislike tests revealed that basic automotive exterior colors, such as black, white and red, were highly preferred across locations. However, geographical differences are apparent in the preference for some non-basic colors. To elucidate these geographical differences, a Chi-square test and principal component analysis were performed on the data on emotion variables. The results revealed both similarities and differences in color preferences among the four locations. Color preferences were similar in Hong Kong and Shanghai when simply evaluated by color samples. However, similar preferences for automotive exterior colors were observed in Hong Kong, Kyoto and Bangkok, but not in Shanghai. These results suggest that there is fluctuation in the emotion evoked by a color when the color is considered in the context of automotive exteriors. Therefore, this study indicates that automotive sales can be secured in the global marketplace by creating a single palette of exterior colors based on similar color preferences across countries. However, these results also indicate that preparing market-specific automotive-color line-ups can be an effective marketing strategy. 相似文献
72.
73.
Recovery of liquid fuel from hydrocarbon-rich microalgae by thermochemical liquefaction 总被引:11,自引:0,他引:11
Yutaka Dote Shigeki Sawayama Seiichi Inoue Tomoaki Minowa Shin-ya Yokoyama 《Fuel》1994,73(12):1855-1857
Liquefaction of Botryococcus braunii, a colony-forming microalga, with high moisture content was performed with or without sodium carbonate as a catalyst for conversion into liquid fuel and recovery of hydrocarbons. A greater amount of oil than the content of hydrocarbons in B. braunii (50 wt% db) was obtained, in a yield of 57–64 wt% at 300 °C. The oil was equivalent in quality to petroleum oil. The recovery of hydrocarbons was a maximum (>95%) at 300 °C. 相似文献
74.
A film of poly(l-lactic acid) (PLLA) consisting of highly oriented α crystals was uniaxially drawn by tensile force. The effects of the draw ratio (DR), draw temperature (Td), and draw stress on the crystal/crystal transformation from the α- to the β-form crystals were studied. At the initial stage of drawing, the highly oriented α crystals of the starting film transformed into a broader orientation distribution, and significant crystal disorder was introduced. Upon further drawing, the α crystals steadily transformed into β crystals with increasing the DR. For the drawing at a constant Td, the crystal transformation proceeded more efficiently at a higher draw rate and, hence, at a higher draw stress. Furthermore, for the drawing at a constant draw rate, the transformation proceeded with DR most efficiently for the tensile draw at a Td around 140 °C, although the draw stress increased with decreasing the Td. The present result combined with the previous finding in the drawing of PLLA by solid-state extrusion [Macromolecules 36 (2003) 3601] suggests that there is a Td of around 140 °C at which the crystal transformation proceeds most efficiently with DR, suggesting that there are two factors that have opposite effects on the efficiency of the crystal transformation with increasing the Td. However, as a result of the combined effects of the Td and DR on the crystal transformation and the ductility increase with the Td, an oriented film consisting predominantly of β crystals was obtained by tensile drawing at a Td in the range of 140-170 °C to the highest DR achieved at each Td. 相似文献
75.
76.
Seki S. Yokoyama K. Sotirelis P. 《IEEE journal of selected topics in quantum electronics》1995,1(2):264-274
By taking into account the electrostatic deformation in the band profiles and the temperature dependence of the optical dephasing time, we study the temperature sensitivity of the differential gain, threshold carrier density, and radiative current density in 1.3-μm InP-based strained-layer quantum-well (QW) lasers. Electrostatic deformation is analyzed by the self-consistent numerical calculation of Poisson's equation, the scalar effective-mass equation for the conduction band, and the multiband effective-mass equation for the valence band. The optical dephasing time is then obtained from the intrasubband scattering rates for electrons and holes within the fully dynamic random phase approximation including carrier-carrier and carrier-phonon interactions on an equal basis. It is clarified that the electrostatic band-profile deformation is one of the dominant mechanisms For determining the temperature sensitivity Of the differential gain, while the optical dephasing time has a pronounced influence on the transparent condition at elevated temperatures. We demonstrate that the electrostatic band-profile deformation and the temperature-dependent optical dephasing play essential roles in determining the high-temperature characteristics of InP-based QW lasers 相似文献
77.
Kobayashi S 《Applied optics》2002,41(14):2679-2685
A point-spread function (PSF) is commonly used as a model of an optical disk readout channel. However, the model given by the PSF does not contain the quadratic distortion generated by the photo-detection process. We introduce a model for calculating an approximation of the quadratic component of a signal. We show that this model can be further simplified when a read-only-memory (ROM) disk is assumed. We introduce an edge-spread function by which a simple nonlinear model of an optical ROM disk readout channel is created. 相似文献
78.
Kurita H. Shimizu T. Yokoyama H. 《IEEE journal of selected topics in quantum electronics》1996,2(3):508-513
We investigated the detailed characteristics of synchronization of mode-locked laser diodes (MLLD's) by subharmonic optical pulse injection. It was shown that optical harmonic injection mode-locking was not very sensitive to injection pulse shapes. In the time domain, subharmonic injection pulses were multiplexed inside the MLLD and these multiplexed pulses effectively modulated the absorbance of the saturable absorber at the MLLD's repetition frequency. It was also found in the spectral domain that injection pulse trains should have optical spectrum components broader than the MLLD's intermode spacing, and injection spectral components should couple to at least two modes of the MLLD 相似文献
79.
80.
H Sentsui R Takami T Nishimori K Murakami T Yokoyama Y Yokomizo 《Canadian Metallurgical Quarterly》1998,60(12):1329-1333
PURPOSE: Lamotrigine (LTG) is recognised as effective add-on therapy for focal epilepsies, but this is the first double-blind, placebo-controlled, crossover study in treatment-resistant generalised epilepsy. METHODS: The study consisted of 2 x 8-week treatment periods followed by a 4-week washout period. Patients received doses of either 75 or 150 mg daily, depending on their concomitant antiepileptic drugs (AEDs). Long-term continuation was offered at the end of the study with open-label LTG. RESULTS: Five centres in Australia recruited 26 patients who were having absence, myoclonic, or generalized tonic-clonic seizures or a combination of these. Twenty-two patients completed the study. There was a significant reduction in frequency of both tonic-clonic and absence seizure types with LTG. A 350% decrease in seizures was observed for tonic-clonic seizures in 50% of cases and for absence seizures in 33% of evaluable cases. Rash was the only adverse effect causing discontinuation. Twenty-three of 26 opted for open-label LTG, with 20 still receiving LTG for a mean of 26 months. In these 20, 80% had > or =50% seizure reduction and five (25%) were seizure free. CONCLUSIONS: This study shows that LTG is effective add-on therapy in patients with refractory generalised epilepsies. Statistically significant reduction in seizures in both absence and tonic-clonic seizure types was seen even with low doses of LTG. 相似文献