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41.
We propose an asymmetric integral imaging method to adjust the resolution and depth of a three‐dimensional image. Our method is obtained by use of two lenticular sheets with different pitches fabricated under the same F/#. The asymmetric integral imaging is the generalized version of integral imaging, including both conventional integral imaging and one‐dimensional integral imaging. We present experimental results to test and verify the performance of our method computationally. 相似文献
42.
Bae Eun Jung Seong-Hun Paeng 《Communications Letters, IEEE》2005,9(6):532-533
Safavi-Naini and Seberry suggested a subliminal channel based on partitioning a set /spl Gamma/ of the generator matrices of error-correcting codes. We give a systematic procedure to partition /spl Gamma/ into E/sub i/'s with |E/sub i/|=2/sup m/ for any m, which is more efficient than the method in Yang, C-N et al., (1997). 相似文献
43.
Seul‐Ki Park So‐Eun Kim Dae‐Yoon Kim Shin‐Woong Kang Seunghan Shin Shiao‐Wei Kuo Seok‐Ho Hwang Seung Hee Lee Myong‐Hoon Lee Kwang‐Un Jeong 《Advanced functional materials》2011,21(11):2129-2139
Robust coatable polarizer is fabricated by the self‐assembly of lyotropic chromonic liquid crystals and subsequent photo‐polymerizing processes. Their molecular packing structures and optical behaviors are investigated by the combined techniques of microscopy, scattering and spectroscopy. To stabilize the oriented Sunset Yellow FCF (H‐SY) films and to minimize the possible defects generated during and after the coating, acrylic acid (AA) is added to the H‐SY/H2O solution and photo‐polymerized. Utilizing cross‐polarized optical microscopy, phase behaviors of the H‐SY/H2O/AA solution are monitored by varying the compositions and temperatures of the solution. Based on the experimental results of two‐dimensional wide angle X‐ray diffraction and selected area electron diffraction, the H‐SY crystalline unit cell is determined to be a monoclinic structure with the dimensions of a = 1.70 nm, b = 1.78 nm, c = 0.68 nm, α = β = 90.0° and γ = 84.5°. The molecular arrangements in the oriented H‐SY films were further confirmed by polarized Fourier‐transform infrared spectroscopy. The polymer‐stabilized H‐SY films show good mechanical and chemical stabilities with a high polarizability. Additionally, patterned polarizers are fabricated by applying a photo‐mask during the photo‐polymerization of AA, which may open new doors for practical applications in electro‐optic devices. 相似文献
44.
Gunhyu Bae Yoo Sang Jeon Min Jun Ko Yuri Kim Seong-Beom Han Ramar Thangam Wonsik Kim Hee Joon Jung Sungkyu Lee Hyojun Choi Sunhong Min Hyunsik Hong Sangwoo Park Seong Yeol Kim Kapil D. Patel Na Li Jeong Eun Shin Bum Chul Park Hyeon Su Park Jun Hwan Moon Yu Jin Kim Uday Kumar Sukumar Jae-Jun Song Soo Young Kim Seung-Ho Yu Yun Chan Kang Steve Park Seung Min Han Dong-Hwee Kim Ki-Bum Lee Qiang Wei Liming Bian Ramasamy Paulmurugan Young Keun Kim Heemin Kang 《Advanced functional materials》2021,31(37):2103409
Developing materials with the capability of changing their innate features can help to unravel direct interactions between cells and ligand-displaying features. This study demonstrates the grafting of magnetic nanohelices displaying cell-adhesive Arg-Gly-Asp (RGD) ligand partly to a material surface. These enable nanoscale control of rapid winding (“W”) and unwinding (“UW”) of their nongrafted portion, such as directional changes in nanohelix unwinding (lower, middle, and upper directions) by changing the position of a permanent magnet while keeping the ligand-conjugated nanohelix surface area constant. The unwinding (“UW”) setting cytocompatibility facilitates direct integrin recruitment onto the ligand-conjugated nanohelix to mediate the development of paxillin adhesion assemblies of macrophages that stimulate M2 polarization using glass and silicon substrates for in vitro and in vivo settings, respectively, at a single cell level. Real time and in vivo imaging are demonstrated that nanohelices exhibit reversible unwinding, winding, and unwinding settings, which modulate time-resolved adhesion and polarization of macrophages. It is envisaged that this remote, reversible, and cytocompatible control can help to elucidate molecular-level cell–material interactions that modulate regenerative/anti-inflammatory immune responses to implants. 相似文献
45.
46.
This study investigates the effect of viewer engagement on gifting items to a streamer in a live video streaming. Data were collected from AfreecaTV, a leading live video streaming platform in South Korea, to examine viewer engagement and gift-giving behavior. After analyzing 2,294,837 viewers over a three-month period, the empirical results provide evidence that viewer engagement is positively associated with gift-giving decisions. However, the impact of viewer engagement on the amount of gifts purchased is different depending on how the engagement is measured (i.e., by stream or by channel). This study empirically proves that the motive for socialization has a high correlation with gift-giving behavior, which is considered as commoditization of a viewer’s social interaction while consuming media. The study concludes with a discussion on practical implications for live video streaming services and suggestions for future research. 相似文献
47.
Rational and Facile Construction of 3D Annular Nanostructures with Tunable Layers by Exploiting the Diffraction and Interference of Light 下载免费PDF全文
This paper reports a rational and facile approach to fabricating arrays of 3D annular nanostructures with tunable layers by utilizing the diffraction and interference of UV light. Based on discretized Fresnel bright spots and standing waves formed within a photoresist film, the structures with nanoscale features are realized using simple, conventional photolithography. The 3D annular nanostructures are produced in arrays of single‐, double‐, and triple‐layered ring structures with the height of single layer on a 100 nm scale. The structural formation process and features of the nanostructures are analyzed and explained through 3D modeling that integrates the effects of both UV exposure dose and chemical kinetics. The approach to generating 3D annular nanostructures with tunable layers and discrete heights can be adapted for various applications that require the 3D structures fabricated over a large area with high throughput. 相似文献
48.
Demonstration of Time‐ and Wavelength‐Division Multiplexed Passive Optical Network Based on VCSEL Array 下载免费PDF全文
Sil‐Gu Mun Eun‐Gu Lee Jie Hyun Lee Heuk Park Sae‐Kyoung Kang Han Hyub Lee Kwangok Kim Kyeong‐Hwan Doo Hyunjae Lee Hwan Seok Chung Jong Hyun Lee Sangsoo Lee Jyung Chan Lee 《ETRI Journal》2016,38(1):9-17
We demonstrate a time‐ and wavelength‐division multiplexed passive optical network system employing a vertical‐cavity surface‐emitting laser array–based optical line terminal transceiver and a tunable bidirectional optical subassembly–based optical network terminal transceiver. A packet error–free operation is achieved after a 40 km single‐mode fiber bidirectional transmission. We also discuss an arrayed waveguide grating, a photo detector array based on complementary metal–oxide–semiconductor photonics technologies, and low‐cost key devices for deployment in access networks. 相似文献
49.
50.
Jinseob Shin Kyomin Shin Hanna Lee Jeong‐Beom Nam Jae‐Eun Jung Jee‐Hyun Ryu Joo‐Hyun Han Kyung‐Do Suh Yong‐Jin Kim Jongwon Shim Junoh Kim Sang‐Hoon Han Kookheon Char Yeon Kyung Kim Jin Ho Chung Min Jung Lee Byeong Cheol Kang Jin‐Woong Kim 《Advanced materials (Deerfield Beach, Fla.)》2010,22(6):739-743