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41.
This paper reviews the existing research activities on signaling and control procedures for IP over optical networks. We focus on the IP‐centric signaling and control architecture based on the generalized multi‐protocol label switching (GMPLS) protocol and analyze various scenarios and technical issues for deploying the IP over an optical network. We analyze the signaling and operations and administration and maintenance requirements for integrating an IP network and an optical network in order to cope with the high bandwidth and poor resource granularity of the optical network, including the optical cross‐connect system. On the basis of network architecture and a reference configuration model, we investigate the GMPLS‐based control architecture and interconnection model appropriate for controlling IP bandwidth and optical lambda resources. The signaling and control procedure based on GMPLS on optical user‐network interface and network‐network interface are comparatively investigated to provide the optical lightpath. We also study protection and restoration procedures to protect link failure when it applies to GMPLS signaling.  相似文献   
42.
In this paper, a profit-aware design metric is proposed to consider the overall merit of a design in terms of power and performance. A statistical design methodology is then developed to improve the economic merit of a design considering frequency binning and product price profile. A low-complexity sensitivity-based gate sizing algorithm is developed to improve economic gain of a design over its initial yield-optimized design. Finally, we present an integrated design methodology for simultaneous sizing and bin boundary determination to enhance profit under an area constraint. Experiments on a set of ISCAS'85 benchmarks show in average 19% improvement in profit for simultaneous sizing and bin boundary determination, considering both leakage power dissipation and delay bounds compared to a design initially optimized for 90% yield at iso-area in 70-nm bulk CMOS technology.  相似文献   
43.
Anodic dissolution characteristics and electrochemical migration (ECM) behavior of Sn-3.0Ag-0.5Cu solder in NaCl and Na2SO4 solutions were investigated using anodic polarization tests and water drop tests (WDT). The ECM lifetime of Sn-3.0Ag-0.5Cu solder in NaCl solution (42.4 s) was longer than that in Na2SO4 solution (34.8 s). The pitting potential of Sn-3.0Ag-0.5Cu solder in NaCl solution (135 mV, SCE) was higher than that in Na2SO4 solution (−367 mV, SCE). The passivity film (SnO2) formed on Sn-3.0Ag-0.5Cu solder during WDTs in NaCl solution was thicker than that formed in Na2SO4 solution. Therefore, the longer ECM lifetime of Sn-3.0Ag-0.5Cu solder in NaCl solution than in Na2SO4 solution can be attributed to the higher pitting potential in the NaCl solution, which is ascribed to the formation of a thicker passivity film (SnO2) in the former. It was confirmed that microelements such as Ag and Cu do not take part in ECM because they form chemically stable intermetallic compounds with Sn. We believe that Sn is the only element that contributes to ECM, and dissolution of Sn at the anode is possibly the rate-determining step of ECM of Sn-3.0Ag-0.5Cu solder.  相似文献   
44.
In this letter, we have studied the inverted staggered thin-film transistor (TFT) using a spin-on-glass (SOG) gate insulator and a low-temperature polycrystalline silicon (poly-Si) by Ni-mediated crystallization of amorphous silicon. The p-channel poly-Si TFT exhibited a field-effect mobility of 48.2 cm2/V ldr s, a threshold voltage of -4.2 V, a gate-voltage swing of 1.2 V/dec, and a minimum off-current of < 4 times 10-13A/ mum at Vds = -0.1 V. Therefore, the gate planarization technology by SOG can be applicable to low-cost large-area poly-Si active-matrix displays.  相似文献   
45.
Structural coloration is closely related to the progress of innovative optoelectronic applications, but the absence of direct, on-demand, and rewritable coloration schemes has impeded advances in the relevant area, particularly including the development of customized, reprogrammable optoelectronic devices. To overcome these limitations, a digital laser micropainting technique, based on controlled thin-film interference, is proposed through direct growth of the absorbing metal oxide layer on a metallic reflector in the solution environment via a laser. A continuous-wave laser simultaneously performs two functions—a photothermal reaction for site-selective metal oxide layer growth and in situ real-time monitoring of its thickness—while the reflection spectrum is tuned in a broad visible spectrum according to the laser fluence. The scalability and controllability of the proposed scheme is verified by laser-printed painting, while altering the thickness via supplementary irradiation of the identical laser in the homogeneous and heterogeneous solutions facilitates the modification of the original coloration. Finally, the proof-of-concept bolometer device verifies that specific wavelength-dependent photoresponsivity can be assigned, erased, and reassigned by the successive application of the proposed digital laser micropainting technique, which substantiates its potential to offer a new route for reprogrammable optoelectronic applications.  相似文献   
46.
Composite multicellular spheroids composed of mesenchymal stem cells (MSCs) and synthetic biodegradable nanofilaments are fabricated. Extracellular‐matrix‐mimicking nanofilaments, prepared from transverse fragmentation of semicrystalline poly(L ‐lactic acid) nanofibers and subsequent surface modification with cell adhesive peptides, are used to form composite multicellular spheroids with MSCs by cellular self‐assembly. The size of the composite spheroids could be readily controlled with the integrated amount of the nanofilaments. The composite spheroids show enhanced adipogenic potential compared to homotypic spheroids. The resultant spheroids are used as building blocks for 3D biohybrid construction with the assistance of a microstructured scaffold fabricated by a direct polymer melt deposition process. An angiogenic growth factor, basic fibroblast growth factor, is also locally delivered in a sustained fashion from the heparinized scaffold surface for facile neovascularization of adipogenic tissue. The produced multiscaled and multifunctional hybrid MSC construct enable the successful formation of vascularized adipose tissue in vivo.  相似文献   
47.
With the development of social media, television viewing is perceived no longer as an isolated activity. This study explores the underlying mechanism of the effects of social viewing discussion networks (i.e., bridging and bonding social viewing networks) on emotions (i.e., anger, fear, and enthusiasm), and moreover on opinion consolidation as well as opinion weakening in the context of the 2017 South Korean presidential debates. Overall, the main results are: a) Social viewing discussion networks influenced emotional states of social viewers, b) Emotions influenced attitude formation during social viewing, and c) Enthusiasm served as a catalyst that links bonding and bridging social viewing, and opinion consolidation. Implications and theoretical contributions are discussed.  相似文献   
48.
In this brief, a low-complexity hardware architecture for multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) symbol detectors with two transmit and two receive antennas is proposed. The detectors support two MIMO-OFDM schemes of space-frequency block coded OFDM and space-division multiplexing OFDM in order to achieve higher performance and throughput. However, symbol detection processes for these two schemes have high computational complexity, which is a burden to hardware implementation of MIMO-OFDM symbol detectors. In order to reduce complexity, the proposed symbol detector is designed with shared architecture, where similar functional blocks are merged and share the hardware resources, and results in the reduction of logic gates by 34% over a conventional architecture employing two individual detectors  相似文献   
49.
Performance analysis of HomePlug 1.0 MAC with CSMA/CA   总被引:1,自引:0,他引:1  
As demands for data communications among home/personal devices in home environments increase, various types of home-networking technologies have appeared. Among them, power line communication is one of the most promising wired home-networking technologies, because the existing power line facilities can be utilized for data transmission without deploying any new physical links. HomePlug 1.0 is the most popular power line communication technology, which has been standardized by the HomePlug power line alliance, and attempts to mitigate the effect of time- and frequency-varying channels by enhanced modulation and channel coding. Although HomePlug 1.0 has undergone field trials and simulations, its analytic model and performance was only conducted for throughput under saturation conditions. We propose a new analytic model to evaluate MAC throughput and delay of HomePlug 1.0 both under saturation and under normal traffic conditions. We verify our proposed model via simulations and evaluate the performance of HomePlug 1.0.  相似文献   
50.
Dissolving microneedle (DMN) is an attractive alternative to parenteral and enteral drug administration owing to its painless self-administration and safety due to non-generation of medical waste. For reproducible and efficient DMN administration, various DMN application methods, such as weights, springs, and electromagnetic devices, have been studied. However, these applicators have complex structures that are complicated to use and high production costs. In this study, a latch applicator that consists of only simple plastic parts and operates via thumb force without any external complex device is developed. Protrusion-shaped latches and impact distances are designed to accumulate thumb force energy through elastic deformation and to control impact velocity. The optimized latch applicator with a pressing force of 25 N and an impact velocity of 5.9 m s−1 fully inserts the drug-loaded tip of the two-layered DMN into the skin. In an ovalbumin immunization test, DMN with the latch applicator shows a significantly higher IgG antibody production rate than that of intramuscular injection. The latch applicator, which provides effective DMN insertion and a competitive price compared with conventional syringes, has great potential to improve delivery of drugs, including vaccines.  相似文献   
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