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1.
The distribution of water diffusion in biological tissues may be estimated by a 3-D Fourier transform (FT) of diffusion-weighted measurements in q-space. In this study, methods for estimating diffusion spectrum measures (the zero-displacement probability, the mean-squared displacement, and the orientation distribution function) directly from the q-space signals are described. These methods were evaluated using both computer simulations and hybrid diffusion imaging (HYDI) measurements on a human brain. The HYDI method obtains diffusion-weighted measurements on concentric spheres in q-space. Monte Carlo computer simulations were performed to investigate effects of noise, q-space truncation, and sampling interval on the measures. This new direct computation approach reduces HYDI data processing time and image artifacts arising from 3-D FT and regridding interpolation. In addition, it is less sensitive to the noise and q-space truncation effects than conventional approach. Although this study focused on data using the HYDI scheme, this computation approach may be applied to other diffusion sampling schemes including Cartesian diffusion spectrum imaging. 相似文献
2.
Teen-Hang Meen Jenn-Kai Tsai Shi-Mian Chao Yu-Chien Lin Tien-Chuan Wu Tang-Yun Chang Liang-Wen Ji Walter Water Wen-Ray Chen I-Tseng Tang Chien-Jung Huang 《Nanoscale research letters》2013,8(1):450
In this study, we prepared different shapes of gold nanoparticles by seed-mediated growth method and applied them on the photoelectrodes of dye-sensitized solar cells (DSSCs) to study the surface plasma resonant (SPR) effect of gold nanoparticles on the photoelectrodes of dye-sensitized solar cells. The analyses of field emission scanning electron microscopy show that the average diameter of the spherical gold nanoparticles is 45 nm, the average length and width of the short gold nanorods were 55 and 22 nm, respectively, and the average length and width of the long gold nanorods were 55 and 14 nm, respectively. The aspect ratio of the short and long gold nanorods was about 2.5 and 4, respectively. The results of ultraviolet–visible absorption spectra show that the absorption wavelength is about 540 nm for spherical gold nanoparticles, and the absorption of the gold nanorods reveals two peaks. One is about 510 to 520 nm, and the other is about 670 and 710 nm for the short and long gold nanorods, respectively. The best conversion efficiency of the dye-sensitized solar cells with spherical gold nanoparticles and short and long gold nanorods added in is 6.77%, 7.08%, and 7.29%, respectively, and is higher than that of the cells without gold nanoparticles, which is 6.21%. This result indicates that the effect of gold nanoparticles on the photoelectrodes can increase the conductivity and reduce the recombination of charges in the photoelectrodes, resulting in the increase of conversion efficiency for DSSCs. In addition, the long gold nanorods have stronger SPR effect than the spherical gold nanoparticles and short gold nanorods at long wavelength. This may be the reason for the higher conversion efficiency of DSSCs with long gold nanorods than those of the cells with spherical gold nanoparticles and short gold nanorods. 相似文献
3.
Chang Yuan-Ming Sung Chia-Yu Sheu Yu-Chien Yu Meng-Shiun Hsu Min-Yih Lee Jenq-Kuen 《The Journal of supercomputing》2021,77(9):10065-10096
The Journal of Supercomputing - With growing applications such as image recognition, speech recognition, ADAS, and AIoT, artificial intelligence (AI) frameworks are becoming popular in various... 相似文献
4.
Yu-Chien Wu Chang-Ting Yang Manting Sun Hsing-I Hsiang 《Journal of the American Ceramic Society》2019,102(4):1548-1552
Defects, such as cracks, porous structure, small grains that easily occur in the fabrication of copper indium gallium selenide (CIGS) thin film absorbers using non-vacuum process have been the major obstacle to practical application of this technology so far. A gas-pressure assisted sintering process has been developed to achieve dense, crack-free, large-grained CIGS films. The gas-pressure assisted sintering effects on the microstructure, crystalline, and electric properties were investigated by scanning electron microscopy, X-ray diffraction, and Hall-effect analyzer. A uniform microstructure with a large grain size and small amount of isolated residual pores and good electric properties can be obtained by pre-sintering at 500°C under 6 bar N2 overpressure and then annealing at 500°C for 20 minutes under a selenium atmosphere. 相似文献
5.
The emergence of Web 2.0 technology provides more opportunities to foster online communication and sharing in an e-learning environment. The purpose of this study was to develop a Web 2.0 annotation system, MyNote, based on the Web 2.0 core concepts which emphasize ease of access and active sharing and then to gain an understanding about people’s perceptions of MyNote from a usability perspective. MyNote was employed on multimedia learning objects in a Learning Management System (LMS), and out of the LMS as well in this study. The evaluation results showed that, with factor analysis, interactivity, usefulness, helpfulness, and willingness for future use were categorized to represent the perceptions of MyNote. It was also found that the factors of interactivity and helpfulness were statistically significant to predict the future use of MyNote. Lastly, the habit of taking notes also affected learners’ perceptions of using MyNote. 相似文献
6.
Lin Chia-Hung Lin Yu-Chien Wu Yen-Jung Chung Wei-Ho Lee Ta-Sung 《Journal of Signal Processing Systems》2021,93(4):369-388
Journal of Signal Processing Systems - Besides the use of information transmission, vehicular communications also perform an essential role in intelligent transportation systems (ITS) for... 相似文献
7.
Jenn-Ming Song Yu-Chien Chang-Chien Bo-Chang Huang Wei-Ting Chen Chi-Rung Shie Chuang-Yao Hsu 《Corrosion Science》2011,(6):2283-2288
For further understanding of the discoloration of solder surfaces due to oxidation during the assembly and operation of electronic devices, UV–vis and X-ray photoelectron spectroscopic analyses were applied to evaluate the degree of discoloring and identify the surface oxides. The decrease in reflectance of the oxidized solder surface is related to SnO whose absorption band is located within the visible region. A trace of P can effectively depress the discoloration of solders under both solid and semi-solid states through the suppression of SnO. 相似文献
8.
Su-Bin Yoon Yu-Chien Ma Akaash Venkat Chun-Yu Liu Jie J. Zheng 《International journal of molecular sciences》2022,23(7)
Retinitis Pigmentosa (RP) is a hereditary retinal disorder that causes the atrophy of photoreceptor rod cells. Since individual defective genes converge on the same disease, we hypothesized that all causal genes of RP belong in a complex network. To explore this hypothesis, we conducted a gene connection analysis using 161 genes attributed to RP, compiled from the Retinal Information Network, RetNet. We then examined the protein interaction network (PIN) of these genes. In line with our hypothesis, using STRING, we directly connected 149 genes out of the recognized 159 genes. To uncover the association between the PIN and the ten unrecalled genes, we developed an algorithm to pinpoint the best candidate genes to connect the uncalled genes to the PIN and identified ten such genes. We propose that mutations within these ten genes may also cause RP; this notion is supported by analyzing and categorizing the known causal genes based on cellular locations and related functions. The successful establishment of the PIN among all documented genes and the discovery of novel genes for RP strongly suggest an interconnectedness that causes the disease on the molecular level. In addition, our computational gene search protocol can help identify the genes and loci responsible for genetic diseases, not limited to RP. 相似文献
9.
The effectiveness of electronic word-of-mouth (eWOM) communication has attracted increasing attention from marketing practitioners,
but relatively few studies focus on the dissemination of eWOM communication from a message perspective. Online video is a
prominent form of marketing promotion, yet again, little is known about which factors make online video engaging or how they
influence recipients’ forwarding intentions. This study adopts Lasswell’s communication model to investigate the persuasiveness
of online video and uses the source, content, and channel dimensions to examine three potentially influential factors: awareness
of persuasive intent, perceived humor, and multimedia effect. Awareness of persuasive intent exerts a negative influence,
whereas the humor and multimedia effects have positive influences on both attitude toward a received online video and forwarding
intentions. Therefore, e-marketers should reshape video clips to be humorous, use multimedia effects, and disguise their commercial
intent to attract recipients’ attention and persuade them to disseminate an online video. 相似文献
10.