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181.
182.
The mechanical and adhesive properties of C60@(10,10) carbon nanopeapods (CNPs) adhering to gold surfaces are investigated by atomistic simulations. The effects of C60 fill density, tube length, surrounding temperature, and peeling velocity on the adhesion behavior are studied. Results show that the interfacial binding energy of CNPs (which depends on the C60 fill density and temperature) is 2.0∼4.4% higher than that of (10,10) single-walled CNTs and 3.4∼4.7% lower than that of (5,5)@(10,10) double-walled CNTs (DWCNTs). Despite their lower interfacial binding energy, CNPs have a higher adhesive strength than that of DWCNTs (1.53 nN vs. 1.4 nN). Distinct from the inner tubes of DWCNTs, which have continuum mechanical properties, the discrete C60 molecules that fill CNPs exhibit unique composite mechanical properties, with high flexibility and bend-buckling resistance. The bend-buckling forces for CNPs filled with a low/medium fill density of C60 are approximately constant. When the fill density is 1 C60 molecule per nanometer length, the bend-buckling force dramatically increases. 相似文献
183.
Yu‐Ta Chen Shau‐Wei Hsu Bao‐Jen Pong Mang Ou‐Yang Cheng‐Chung Lee 《Journal of the Society for Information Display》2013,21(6):231-238
This work presents an image displacement measurement by using a box pattern and the edge spread function analysis in the polarized based stereoscopic displays. The measurement determines to identify three factors (i.e., box size, image displacement, and spatial frequency response (SFR)) from the box patterns. The polarized based stereoscopic displays might sacrifice pixels for producing 3D images, which might produce errors in the image displacement and then affect the depth perception indirectly. Based on the measurement, the errors can be quantified by using the three factors. Owing to the light leakage distorting the edge spread function to obtain an inferior SFR, exactly how light leakage affects the edge spread function can be resolved on the basis of the SFR results, especially at a frequency (1/display pixel) of 1.9 in the case of the horizontal displacement. Light leakage also induces the error of the box height in even and odd intervals of the vertical displacements more than 2 pixels and 0.5 pixels, respectively. The image displacement measurement provides a simple and comprehensive means of evaluating the optical characteristics, disparity, and sharpness of the stereoscopic displays, via the three factors. 相似文献
184.
Epidural fibrosis, an inevitable part of the postoperative healing process, is one of the important causes of failed back surgery syndrome after spinal surgery. The aim of this study was to examine the inhibitory effect of a novel material 1,4-butanediol diglycidyl ether-cross-linked hyaluronan (cHA) on fibrosis in primary tenocytes. cHA inhibited migration, cell proliferation, and suppressed the expression of fibronectin, but not transforming growth factor-β, in primary tenocytes. cHA significantly increased matrix metalloproteinase-3 but decreased collagen-1 and microtubule-associated protein light chain 3-II expression in a dose-dependent manner compared with control groups. We therefore concluded that suppressing autophagy activity may be involved in the anti-fibrotic effect of cHA in primary tenocytes. Further, cHA may have the potential for preventing epidural fibrosis and subsequent failed back syndrome in patients with laminectomy in the future. 相似文献
185.
186.
Chua-Chin Wang Chia-Hao Hsu Gang-Neng Sung Yu-Cheng Lu 《Journal of Signal Processing Systems》2012,66(2):87-92
A low power digital signed array multiplier based on a 2-dimensional (2-D) bypassing technique is proposed in this work. When
the horizontally (row) or the vertically (column) operand is zero, the corresponding bypassing cells skip redundant signal
transitions to avoid unnecessary calculation to reduce power dissipation. An 8×8 signed multiplier using the 2-D bypassing
technique is implemented on silicon using a standard 0.18 μm CMOS process to verify power reduction performance. The power-delay
product of the proposed 8×8 signed array multiplier is measured to be 31.74 pJ at 166 MHz, which is significantly reduced
in comparison with prior works. 相似文献
187.
While the market turns to an environment with low profit margins for semiconductor backend operations, it is hard for an independent firm to survive today. Forming strategic alliances or integrating an enterprise's internal firms by means of collaborative planning/operations to gain competitive advantage is inevitable. This paper presents the development of an activity-based costing collaborative production planning system (ABC/CPPS) to help production planners to estimate the manufacturing profit of semiconductor backend turnkey (combined IC assembly and testing) operational services at the early stage of order release to production line in a collaborative context. The estimation is under the real constraints of production resources. A predicate/transition net (Pr/Tr net) is used to simulate and implement the activity-based costing (ABC) model with the dynamic characteristics of a production line incorporated. A financial measure, profit, is used to supplement and indicate the consequence of the planning result and link the view to the enterprise's financial vision. 相似文献
188.
189.
Abstract A numerical technique for integrating the full Navier‐Stokes and diffusion equations through an initial value problem has been used to investigate the time development of a line buoyant source issuing in a density‐stratified environment. The basic physical features and some structures of the interactions of the motion at the intermediate mixing region are obtained. Results show that the stratification tends to inhibit the flow development of the buoyant source and to encourage the formation of a recirculatory vortex on the lower region near the source and the upper region. 相似文献
190.
Fu-Hau Hsu Min-Hao Wu Cheng-Hsing Yang Shiuh-Jeng Wang 《The Journal of supercomputing》2014,70(1):247-268
Digital watermarking technology is primarily the joining of the rightful owner of the protected media. Once the media are suspected to be illegally used, an open algorithm can be used to extract the digital watermark for the purpose of showing the media’s ownership. From a hidden watermark in the media from the appearance point of view, general digital watermarking technologies can be divided into two categories: visible watermark technology and invisible watermark technology. Visual watermark technology embeds a watermark into the protected media to declare ownership and deter pirate behavior. In this paper, we propose a reversible visible watermark method, which embeds a binary-imaged watermark into gray-scale images to create a visible watermark. Not using complex calculations, this paper tries to simply change the pixel value to achieve the digital watermark, where our scheme is also against the possible detections with LSB-based manners in use. Furthermore, a reversible steganographic method is used to embed the watermarking information into the watermarking images. The watermark information can then be used to recover the original images. 相似文献