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101.
102.
Seok Ho Won 《ETRI Journal》2013,35(6):1068-1074
This paper proposes an additional forward error correction (FEC) layer to compensate for the defectiveness inherent in the conventional FEC layer in the Long Term Evolution specifications. The proposed additional layer is called a graceful degradation (GD)‐FEC layer and maintains desirable service quality even under burst data loss conditions of a few seconds. This paper also proposes a non‐delayed decoding (NDD)‐GD‐FEC layer that is inherent in the decoding process. Computer simulations and device‐based tests show a better loss recovery performance with a negligible increase in CPU utilization and occupied memory size. 相似文献
103.
Sang Gi Kim Hoon Soo Park Kyoung Il Na Seong Wook Yoo Jongil Won Jin Gun Koo Sang Hoon Chai Hyung‐Moo Park Yil Suk Yang Jin Ho Lee 《ETRI Journal》2013,35(4):632-637
In this paper, we propose a superjunction trench gate MOSFET (SJ TGMOSFET) fabricated through a simple p pillar forming process using deep trench and boron silicate glass doping process technology to reduce the process complexity. Throughout the various boron doping experiments, as well as the process simulations, we optimize the process conditions related with the p pillar depth, lateral boron doping concentration, and diffusion temperature. Compared with a conventional TGMOSFET, the potential of the SJ TGMOSFET is more uniformly distributed and widely spread in the bulk region of the n drift layer due to the trenched p‐pillar. The measured breakdown voltage of the SJ TGMOSFET is at least 28% more than that of a conventional device. 相似文献
104.
Yuan Gao Takashi Kodama Yoonjin Won Senyo Dogbe Lawrence Pan Kenneth E. Goodson 《Carbon》2012,50(10):3789-3798
The mechanical compliance of vertically aligned carbon nanotube (VACNT) films renders them promising as interface materials that can accommodate thermal expansion mismatch. Here we study the relationship between the detailed morphology and elastic modulus of multi-walled VACNT films with thicknesses ranging from 98 to 1300 μm. A systematic analysis of scanning electron micrographs reveals variations in nanotube alignment and density among samples and within different regions of a given film. Nanoindentation of both top and bottom film surfaces using an atomic force microscope with spherical indenters with radii between 15 and 25 μm provides evidence of the modulus differences. The top surface is shown to have a higher modulus than the base, with out-of-plane modulus values of 1.0–2.8 MPa (top) and 0.2–1.4 MPa (base). The indentation data and microstructural information obtained from electron microscopy are interpreted together using an open cell foam model to account for differences in nanotube alignment and density, which are generally lower at the base and yield predictions that are consistent with the modulus data trends. This work shows that microstructure analysis complements property measurements to improve our understanding of nanostructured materials. 相似文献
105.
In Guk Hwang Hyun Young Kim Sang Hoon Lee Koan Sik Woo Jung Ok Ban Jin Tae Hong Kwang Won Yu Junsoo Lee Heon Sang Jeong 《Food chemistry》2012,130(3):547-551
We isolated a substance from fructose–tyrosine Maillard reaction products (MRPs) and investigated its antiproliferative effect on six human cancer cell lines. The ethyl acetate fraction of fructose–tyrosine MRPs showed a strong antiproliferative effect; this fraction was isolated and purified using silica gel column chromatography, semipreparative RP-HPLC, and recycling HPLC. The structure of the purified compound was determined using spectroscopic methods. The isolated compound was identified as 2,4-bis(p-hydroxyphenyl)-2-butenal (C16H14O3, HPB242). HPB242 inhibited cell growth in a dose-dependent manner (10–80 μg/ml) on the six human cancer cell lines. The IC50 values of HPB242 on the six human cancer cell lines were 17.34 μg/ml (MCF-7), 29.21 μg/ml (HCT-116), 34.57 μg/ml (H-460), 34.87 μg/ml (HepG2), 48.77 μg/ml (PC-3), and 55.83 μg/ml (MKN-45). 相似文献
106.
Myoung Do Seo Young Jo Kim Jong Sung Lim Jeong Won Kang 《Korean Journal of Chemical Engineering》2012,29(1):103-110
Vapor-liquid equilibrium (VLE) for binary mixtures composed of ethanol+methyl isobutyl ketone, 1-butanol+ methyl ethyl ketone,
and 1-butanol+methyl propyl ketone systems was measured using a circulation type equilibrium apparatus at atmospheric pressure.
The measured data and literature data for alcohol and ketone systems have been correlated by the UNIversal Quasi-Chemical
(UNIQUAC) model with two binary interaction parameters and the non-random lattice fluid equation of state with hydrogen bonding
equation of state (NLF-HB EoS) using a single binary interaction parameter. For the NLF-HB EoS calculations, the numbers of
proton acceptor for ketones were adjusted between 0 and 1. The calculation results with the NLF-HB EoS are better than those
with the UNIQUAC model. 相似文献
107.
Geographic routing is well suited for large scale sensor networks, because its per node state is independent of the network size. However, the local minimum caused by holes/obstacles results in the worst-case path stretch of Ω(c2), where c is the path length of the optimal route. Recently, a geographic routing protocol based on the visibility graph (VIGOR) showed that a path stretch of Θ(c) can be achieved. This path stretch, however, is achieved at the cost of communication and storage overhead, which makes the practical deployment of VIGOR in large scale sensor networks challenging. To this end, we propose GOAL (Geometric Routing using Abstracted Holes), a routing protocol that provably achieves a path stretch of Θ(c), with lower communication and storage overhead. To compactly describe holes, we develop a novel distributed convex hull algorithm, which improves the message complexity O(n log2 n) of state of art distributed convex hull algorithm to O(n log n). The concise representation of a hole is used by nodes to make locally optimal routing decisions. Our theoretical analysis proves the correctness of the proposed algorithms and the path stretch of Θ(c). Through extensive simulations and experiments on a testbed with 42 EPIC motes, we demonstrate the effectiveness of GOAL and its feasibility for resource constrained wireless sensor networks; specifically, we show that GOAL eliminates part of communication overhead of VIGOR and reduces the memory overhead of VIGOR by up to 51%. 相似文献
108.
109.
110.
A Highly Planar Fluorinated Benzothiadiazole‐Based Conjugated Polymer for High‐Performance Organic Thin‐Film Transistors 下载免费PDF全文