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991.
Ki‐Chan Lee Kyoung‐Uk Choi Sang‐Gil Lee Yun‐Jae Park Hyun‐Seok Ko Seung‐Hwan Moon Brian H. Berkeley 《Journal of the Society for Information Display》2010,18(2):146-152
Abstract— Novel LED backlight driving technology with a fully embedded LED driver IC is presented. This driving system and IC feature a high speed reduced swing differential signaling (RSDS) interface, an independent PWM controller with high‐resolution programming, and embedded scan logic. To attain high efficiency from the boost converter, highly advanced dynamic headroom control technology has been implemented onto the IC. The embedded current boosting function showed almost no brightness reduction when operated in scanning mode. The scanning function of the system improved motion blur values 26–44% compared to that of a non‐scanning LCD panel. 相似文献
992.
Sliding friction between cellulose Iβ nanocrystals is studied using molecular dynamics simulation. The effects of sliding velocity, normal load, and relative angle between sliding surface are predicted, and the results analyzed in terms of the number of hydrogen bonds within and between the cellulose chains. We find that although the observed friction trends can be correlated with hydrogen bonding, it may not be the most significant factor in determining frictional behavior on cellulose nanocrystal surfaces. 相似文献
993.
The economic lot-scheduling problem (ELSP) is an important production scheduling problem that has been intensively studied over 40 years. Numerous heuristic algorithms have been developed since the problem is NP-hard. Dobson's heuristic has been regarded as the best in its performance. The present paper provides a hybrid genetic algorithm based on the time-varying lot sizes approach in the ELSP literature. Numerical experiments show that the hybrid genetic algorithm outperforms Dobson's heuristic. 相似文献
994.
Modular assembly is being applied to an increasing number of vehicles and part manufacturers to manage the ever-changing demands of the automotive industry. In spite of many researches performed on the supply chain management and logistics aspects of modular production, there is no research discussing modular production line concepts used by module suppliers. In this paper, labour productivity of two assembly line concepts including the conveyor line and box assembly line is studied under modular production environment. Both line concepts and respective assembly processes are described in detail. Mathematical models showing the total work faced by these two assembly line concepts are developed and compared. Two productivity scales are defined: the maximum achievable productivity and the actual productivity. The labour productivity rates of these assembly line concepts on above productivity scales obtained from calculations and a simulation are compared as a performance measure. 相似文献
995.
996.
The adsorption behavior of Eu(III) onto silica surface, which was partially coated with Fe(III) or Ti(IV), was investigated to determine Fe(III) or Ti(IV) effects on the surface reaction of lanthanides on mineral surfaces in groundwater. Compared with a parallel uncoated silica, the Fe(III)-coated silica did not enhance the adsorption of Eu(III). However, enhanced adsorption of Eu(III) on the Ti(IV)-coated silica was observed by increasing the amount of Ti(IV) on the silica surface. 相似文献
997.
Skyler Weaver Benjamin Hershberg Pavan Kumar Hanumolu Un-Ku Moon 《Analog Integrated Circuits and Signal Processing》2012,73(1):143-149
A ones adder is an important circuit block that is required in many varying applications. This work proposes a design that largely relies on passive transmission-gate multiplexers. Many variations are suggested that can inherently generate a thermometer coded output or one-hot encoded output. The proposed structure has area and power that increases with order n 2 for a n number of inputs. A folding technique is then suggested that reduces the area/power to order n log(n). The folded passive linear counter also has a cell-based structure that aids in layout and makes it possible to be added to a digital standard cell library. 相似文献
998.
Do Wan Kim Ho Jae Lee Moon Hwan Kim Sang-young Lee Tae-yeong Kim 《International Journal of Control, Automation and Systems》2012,10(6):1164-1172
This paper presents a new direct discrete-time design methodology of a robust sampled-data fuzzy controller for a class of nonlinear system with parametric uncertainties that is exactly represented by Takagi-Sugeno (T-S) fuzzy model. Based on an exact discrete-time fuzzy model in an integral form, sufficient conditions for a robust asymptotic stabilization of the nonlinear system are investigated in the discrete-time Lyapunov sense. It is shown that the resulting sampled-data controller indeed robustly asymptotically stabilizes the nonlinear plant. To illustrate the effectiveness of the proposed methodology, an example, a sampled-data depth control of autonomous underwater vehicles (AUVs) is provided. 相似文献
999.
Sung-Gul HongBong-Ho Cho Kyung-Soo ChungJu-hyuk Moon 《Journal of Constructional Steel Research》2011,67(6):936-946
A new type of lateral force-resisting system, a framed modular building with double skin steel panels of slender thin steel plates is presented. Modular construction leads to faster construction, improved quality and reduced resources and waste. A steel panel strengthened framed modular system is developed for the lateral load resisting system instead of in situ concrete core walls. The proposed double skin steel panel systems showed moderate ductility and energy dissipation due to their post-buckling strength. Full-scale experiments on a framed modular system with double skin steel panels were conducted. The test of the frame with steel panel systems showed that all steel panel systems reached a yielding point before the frame structure started to yield, so that severe damage to the frame as a primary structure was controlled. Also, the steel panel systems increased the initial lateral stiffness of the total system and maintained the elastic range of the panels up to near the yielding point of plates without local buckling driven from its shear behavior. By rigid-plastic analysis, the post-buckling strength of thin plates under in-plane bending was predicted and compared with experimental results. Based on the experimental data of the panels, the analytic model of these panel systems was constructed and compared with the experimental results of frames with double skin steel panel systems. 相似文献
1000.
M.M.A. Sarker G.J. Shim H.S. Lee C.G. Moon J.I. Yoon 《Applied Thermal Engineering》2009,29(16):3328-3333
Performance characteristics of the Hybrid Closed Circuit Cooling Tower (HCCCT) have been tested experimentally. Bare-type copper tubes and fin tubes were used in staggered arrangement at the heat exchanger of the HCCCT and the cooling capacity and pressure drop have been studied from various perspectives. The relevant temperatures and velocities were selected based on the typical East Asian meteorological constraints for the year round operation of the HCCCT. Performance characteristics were compared and found that for the fin tubes, cooling capacities were about 22% and 260% higher than those of the bare tubes in wet and dry modes, respectively. The pressure drop for the fin tubes was nearly two times higher than that of the bare tubes in both modes. The experimental results show considerable enhancement of cooling capacity. 相似文献