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71.
Hoo Kun Lee Myeong Soo Jeong Joo Wan Park Hyun Soo Park Jong Hyun Cho 《Korean Journal of Chemical Engineering》1990,7(1):13-17
An absorption efficiency of packed column removing nitrogen oxides with water and NaOH solution under atmospheric pressure
was studied. The efficiency and the acidity produced by absorption of NO, were measured in a packed column. The model developed
that was based on the mass-transfer information for packed column and absorption mechanism accompanying the chemical reaction
was compared with experimental results. Predictions using the model presented by the previous paper (part 1) was shown well
to agree with from the experimental results (part II). The efficiency of NOx, absorption is largely dependent on the height of packing material and the partial pressure of NOx in the feed gas. The efficiency of NOx absorption decreases with the increase of the acidity produced by recycling of water as a scrubber liquid. For the recycle
mode with an aqueous NaOH solution as a scrubber liquid, NOx absorption efficiency is shown to be constant until all of the COH- in the scrubber liquid are converted into CH+. 相似文献
72.
We propose an efficient scheme for camera motion characterization in MPEG‐compressed video. The proposed scheme detects six types of basic camera motions through threshold‐based qualitative interpretation, in which fixed thresholds are applied to motion model parameters estimated from MPEG motion vectors (MVs). The efficiency and robustness of the scheme are validated by the experiment with real compressed video sequences. 相似文献
73.
In Hwan Park Yoon Hyun Kim Jae Sang Cha Yeong Min Jang Jin Young Kim 《Wireless Personal Communications》2011,60(3):533-545
In this paper, effects of reader-to-reader interference are investigated for LED identification (LED-ID) system in a multi-reader
environment. The LED-ID readers typically use different channels to avoid collision between readers. However, in-channel collision
usually happens in terms of interrogation range. A reader-to-reader interference scenario is proposed, and nominal interrogation
range of a desired reader is derived from this model. In order to evaluate the LED-ID reader-to-reader interference quantitatively,
an efficient detection scheme is proposed and simulated by employing spreading sequence. The spreading sequence is inserted
between each user’s frame formats. In the receiver, the desired signal is detected by using correlation among inserted spreading
sequences. From simulation results, it is confirmed that the proposed scheme is very effective to enhance reliability of LED-ID
communication systems. 相似文献
74.
Jin Woo Lee Kihyun Kim Jin Sun Jung Seong Gi Jo Hyo-min Kim Hyun Soo Lee Jeongyong Kim Jinsoo Joo 《Organic Electronics》2012,13(10):2047-2055
Intrinsic characteristics of organic and inorganic nanostructures depend on their physical dimensions (i.e., size and shape) and crystallinity. Here, we compared the nanoscale optical and electrical properties of organic rubrene one-dimensional (1-D) nanorods (NRs) and two-dimensional (2-D) nanosheets (NSs). From high-resolution laser confocal microscope photoluminescence (PL) measurements, the light-emission characteristics of 2-D rubrene NSs varied with the crystalline domain direction, indicating intrinsic PL anisotropy, which was distinguishable from 1-D rubrene single NRs, because of anisotropy π–π stacking molecular arrangements. We also observed the variation of charge carrier mobility depending on the measured directions (i.e., anisotropy of charge transport) in rubrene NS-based field-effect transistors. The optical waveguiding properties of rubrene nanostructures were strongly correlated to the dimensionality of materials and PL anisotropy. 相似文献
75.
A mode‐singular‐value‐decomposition (SVD) maximum likelihood (ML) estimation procedure is proposed for the source localization problem under an additive measurement error model. In a practical situation, the noise variance is usually unknown. In this paper, we propose an algorithm that does not require the noise covariance matrix as a priori knowledge. In the proposed method, the weight is derived by the inverse of the noise magnitude square in the ML criterion. The performance of the proposed method outperforms that of the existing methods and approximates the Taylor‐series ML and Cramér‐Rao lower bound. 相似文献
76.
Dong Hyuk Park Hyun Seung Kim Mi‐Yun Jeong Yong Baek Lee Hyun‐Jun Kim Dae‐Chul Kim Jeongyong Kim Jinsoo Joo 《Advanced functional materials》2008,18(17):2526-2534
We report on the significantly enhanced photoluminescence (PL) of hybrid double‐layered nanotubes (HDLNTs) consisting of poly(3‐methylthiophene) (P3MT) nanotubes with various doping levels enveloped by an inorganic, nickel (Ni) metal nanotube. From laser confocal microscopy PL experiments on a single strand of the doped‐P3MT nanotubes and of their HDLNTs, the PL peak intensity of the HDLNT systems increased remarkably up to ~350 times as the doping level of the P3MT nanotubes of the HDLNTs increased, which was confirmed by measurements of the quantum yield. In a comparison of the normalized ultraviolet and visible absorption spectra of the doped‐P3MT nanotubes and their HDLNTs, new absorption peaks corresponding to surface‐plasmon (SP) energy were created at 563 and 615 nm after the nanoscale Ni metal coating onto the P3MT nanotubes, and their intensity increased on increasing the doping level of the P3MT nanotube. The doping‐induced bipolaron peaks of the HDLNTs of doped‐P3MT/Ni were relatively reduced, compared with those of the doped‐P3MT nanotubes before the Ni coating, due to the charge‐transfer effect in the SP‐resonance (SPR) coupling. Both energy‐transfer and charge‐transfer effects due to SP resonance contributed to the very‐large enhancement of the PL efficiency of the doped‐P3MT‐based HDLNTs. 相似文献
77.
A novel linear switched termination active cross‐coupled low‐voltage differential signaling (LVDS) transceiver operating at 1.5 GHz clock frequency is presented. On the transmitter side, an active cross‐coupled linear output driver and a switched termination scheme are applied to achieve high speed with low current. On the receiver side, a shared preamplifier scheme is employed to reduce power consumption. The proposed LVDS transceiver implemented in an 80 nm CMOS process is successfully demonstrated to provide a data rate of 6 Gbps/pin, an output data window of 147 ps peak‐to‐peak, and a data swing of 196 mV. The power consumption is measured to be 4.2 mW/pin at 1.2 V. 相似文献
78.
Fluorinated Polyimide as a Novel High‐Voltage Binder for High‐Capacity Cathode of Lithium‐Ion Batteries 下载免费PDF全文
An increase in the energy density of lithium‐ion batteries has long been a competitive advantage for advanced wireless devices and long‐driving electric vehicles. Li‐rich layered oxide, xLi2MnO3?(1?x)LiMn1?y?zNiyCozO2, is a promising high‐capacity cathode material for high‐energy batteries, whose capacity increases by increasing charge voltage to above 4.6 V versus Li. Li‐rich layered oxide cathode however suffers from a rapid capacity fade during the high‐voltage cycling because of instable cathode–electrolyte interface, and the occurrence of metal dissolution, particle cracking, and structural degradation, particularly, at elevated temperatures. Herein, this study reports the development of fluorinated polyimide as a novel high‐voltage binder, which mitigates the cathode degradation problems through superior binding ability to conventional polyvinylidenefluoride binder and the formation of robust surface structure at the cathode. A full‐cell consisting of fluorinated polyimide binder‐assisted Li‐rich layered oxide cathode and conventional electrolyte without any electrolyte additive exhibits significantly improved capacity retention to 89% at the 100th cycle and discharge capacity to 223–198 mA h g?1 even under the harsh condition of 55 °C and high charge voltage of 4.7 V, in contrast to a rapid performance fade of the cathode coated with polyvinylidenefluoride binder. 相似文献
79.
Sanghoon Kim Seung Hyun Jaeyong Lee Kyu Seong Lee Woo Lee Jin Kon Kim 《Advanced functional materials》2018,28(23)
Two types (hard and soft) of the molds are widely used in nanoimprint lithography for a high throughput over a large area, and high‐resolution parallel patterning. Although hard molds have proven excellent resolutions and can be used at high temperatures, cracks often occur in the mold in addition to the requirement of high imprinting pressure. On the other hand, though soft molds can operate at lower pressures, they give poor pattern resolution. Here, a novel hybrid mold of anodized aluminum oxide (AAO) template attached to a flexible polydimethylsiloxane (PDMS) plate is introduced. Due to the flexible nature of PDMS, various polymer nanostructures are obtained on flat and curved substrates without crack formation on the AAO mold surface. Furthermore, the hybrid mold is successfully used for roll‐to‐roll imprinting for the fabrication of high density array of various shaped polymeric nanostructures over a large area. 相似文献
80.
Spinal Cord Scaffolds: 3D Printed Stem‐Cell Derived Neural Progenitors Generate Spinal Cord Scaffolds (Adv. Funct. Mater. 39/2018) 下载免费PDF全文