著者
Xing Xiaoxiong Dobashi Yoshinori Yamamoto Tsuyoshi Katsura Yosuke Anjyo Ken
出版者
The Institute of Electronics, Information and Communication Engineers (IEICE)
雑誌
IEICE transactions on information and systems (ISSN:17451361)
巻号頁・発行日
vol.E98, no.2, pp.404-411, 2015-02

We present an algorithm for efficient rendering of animated hair under a dynamic, low-frequency lighting environment. We use spherical harmonics (SH) to represent the environmental light. The transmittances between a point on a hair strand and the light sources are also represented by SH functions. Then, a convolution of SH functions and the scattering function of a hair strand is precomputed. This allows us to efficiently compute the intensity at a point on the hair. However, the computation of the transmittance is very time-consuming. We address this problem by using a voxel-based approach: the transmittance is computed by using a voxelized hair model. We further accelerate the computation by sampling the voxels. By using our method, we can render a hair model consisting of tens of thousands of hair strands at interactive frame rates.
著者
Yamamoto Tsuyoshi Nakamura Atsuko Iwai Hiroaki Ishii Tadashi Ma Jian Feng Yokoyama Ryusuke Nishitani Kazuhiko Satoh Shinobu Furukawa Jun
出版者
Springer Japan
雑誌
Journal of plant research (ISSN:09189440)
巻号頁・発行日
vol.125, no.6, pp.771-779, 2012-11
被引用文献数
64 3

Rice (Oryza sativa L.) is a typical Si-accumulating plant and is able to accumulate Si up to >10 % of shoot dry weight. The cell wall has been reported to become thicker under Si-deficient condition. To clarify the relationship between Si accumulation and cell wall components, the physical properties of, and macromolecular components and Si content in, the pectic, hemicellulosic, and cellulosic fractions prepared from rice seedlings grown in hydroponics with or without 1.5 mM silicic acid were analyzed. In the absence of Si (the −Si condition), leaf blades drooped, but physical properties were enhanced. Sugar content in the cellulosic fraction and lignin content in the total cell wall increased under −Si condition. After histochemical staining, there was an increase in cellulose deposition in short cells and the cell layer just beneath the epidermis in the −Si condition, but no significant change in the pattern of lignin deposition. Expression of the genes involved in secondary cell wall synthesis, OsCesA4, OsCesA7, OsPAL, OsCCR1 and OsCAD6 was up-regulated under −Si condition, but expression of OsCesA1, involved in primary cell wall synthesis, did not increase. These results suggest that an increase in secondary cell wall components occurs in rice leaves to compensate for Si deficiency.
著者
Akiyama Suguru Kurahashi Teruo Morito Ken Yamamoto Tsuyoshi Usuki Tatsuya Nomura Shintaro
出版者
Optical Society of America
雑誌
Optics Express (ISSN:10944087)
巻号頁・発行日
vol.20, no.15, pp.16321-16338, 2012-07
被引用文献数
14 2

A cascaded-ring-resonator-loaded Mach–Zehnder modulator (CRR-MZM) is presented in which a number of cascaded ring resonators (RRs) are loaded in the interferometer as phase modulators. The ability of the design to provide enhanced modulation efficiency at a wide optical bandwidth is demonstrated in comparison with a conventional single-RR-type modulator without an interferometer. The optimization of RRs for the CRR-MZM is investigated experimentally by measuring the transmission spectra in both intensity and group delay of RRs having various structural parameters. Using the optimized parameters, we fabricated a CRR-MZM with 10 cascaded RRs loaded on each arm of the interferometer on a silicon-on-insulate substrate. The RRs had pin-diodes along the waveguides, which were operated with forward bias voltage. Its modulation efficiency was enhanced by a factor of 4.4 at the expense of additional loss of less than 3.5 dB compared with a standard non-resonant MZM. 10 Gb/s-operations of CRR-MZM were successfully demonstrated using pre-emphasized RF signals with amplitude of 1.5 Vpp in a wavelength range of 2 nm.