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11.
Connie Tee Goh Michael Kah Ong Teoh Andrew Beng Jin 《Multimedia Tools and Applications》2018,77(21):28457-28482
Multimedia Tools and Applications - Gait recognition has become popular due to the rising demand for nonintrusive biometrics. At its nascent stage of development, gait recognition faces a number of... 相似文献
12.
This paper describes a bridge condition assessment model that is based upon the simplification of a computational technique called resolution identity of fuzzy sets. The proposed model utilizes a fuzzy weighted average to combine fuzzy bridge condition ratings. The procedure is based on the decomposition of fuzzy sets into non-fuzzy level-sets or intervals. The utility and effectiveness of this procedure are illustrated with an example of the bridge condition assessment problem. 相似文献
13.
In this paper, an effective medium access control protocol is proposed for Ethernet passive optical networks. By combining the bandwidth guarantee polling (BGP) scheme with the strict priority queuing (SPQ) mechanism, the proposed solution can greatly mitigate the light-load penalty while supporting differentiated services. The performance of the proposed solution has been demonstrated by the simulation results. 相似文献
14.
Bryant A.T. Yalan Wang Finney S.J. Tee Chong Lim Palmer P.R. 《Power Electronics, IEEE Transactions on》2007,22(2):374-383
Feedback control of insulated gate bipolar transistors (IGBTs) in the active region can be used to regulate the device switching trajectory. This facilitates series connection of devices without the use of external snubber networks. Control must be achieved across the full active region of the IGBT and must balance a number of conflicting system goals including diode recovery. To date, the choice of control parameters has been a largely empirical process. This paper uses accurate device models and formalized optimization procedures to evaluate IGBT active voltage controllers. A detailed optimization for the control of IGBT turn-on is presented in this paper 相似文献
15.
C. J. Christopher M. N. James E. A. Patterson K. F. Tee 《International Journal of Fracture》2007,148(4):361-371
This work introduces a novel mathematical model of the stresses around the tip of a fatigue crack, which considers the effects
of plasticity through an analysis of their shielding effects on the applied elastic field. The ability of the model to characterize
plasticity-induced effects of cyclic loading on the elastic stress fields is assessed and demonstrated using full-field photoelasticity.
The focus is on determining the form of the shielding stress components (induced by compatibility requirements at the elastic–plastic
interface along the crack flank and via the crack tip plastic zone) and how they influence the crack tip elastic stress fields
during a load cycle. The model is successfully applied to the analysis of a fatigue crack growing in a polycarbonate CT specimen. 相似文献
16.
Nanoporous Gold Bowls: A Kinetic Approach to Control Open Shell Structures and Size‐Tunable Lattice Strain for Electrocatalytic Applications 下载免费PDF全文
Srikanth Pedireddy Hiang Kwee Lee Charlynn Sher Lin Koh Joel Ming Rui Tan Weng Weei Tjiu Xing Yi Ling 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(33):4531-4540
Controlling sub‐10 nm ligament sizes and open‐shell structure in nanoporous gold (NPG) to achieve strained lattice is critical in enhancing catalytic activity, but it remains a challenge due to poor control of reaction kinetics in conventional dealloying approach. Herein, a ligament size‐controlled synthesis of open‐shell NPG bowls (NPGB) through hetero‐epitaxial growth of NPGB on AgCl is reported. The ligament size in NPGB is controlled from 6 to 46 nm by varying the hydroquinone to HAuCl4 ratio. The Williamson–Hall analysis demonstrates a higher lattice strain in smaller ligament size. In particular, NPGB with 6 nm (NPGB 6) ligament size possess the highest strain of 15.4 × 10?3, which is nearly twice of conventional 2D NPG sheets (≈8.8 × 10?3). The presence of high surface energy facets in NPGBs is also envisaged. The best electrocatalytic activity toward methanol oxidation is observed in NPGB 6 (27.8 μA μg?1), which is ≈9‐fold and 3‐fold higher than 8 nm solid Au nanoparticles, and conventional NPG sheets. The excellent catalytic activity in NPGB 6 is attributed to the open‐shell structure, lattice strain, and higher electro‐active surface area, allowing efficient exposure of catalytic active sites to facilitate the methanol oxidation. The results offer a potential strategy for designing next generation electrocatalysts. 相似文献
17.
The transient response of antiresonant reflecting optical waveguide (ARROW) vertical-cavity surface-emitting lasers (VCSELs) is analyzed. It is found that under current modulation, the radiation loss of the transverse-leaky mode decreases during the state of the lasers but increases during the state. Numerical analysis shows that this variation in radiation loss is due to the carrier-induced refractive-index depression that arises from spatial-hole-burning of carrier concentration. It is noted that the increment in radiation loss during the state can be used to prevent net modal gain of the transverse-leaky mode from reacquiring threshold after turn-off. Hence, a new method to design ARROW, based on the variation in radiation loss, is proposed to eliminate the excitation of secondary pulsation in VCSELs. The influence of thermal lensing effects on the excitation of secondary pulsation during the state of the lasers is also investigated. 相似文献
18.
Joint trellis-coded quantisation (TCQ) and trellis-coded modulation (TCM) can achieve considerable signal-to-quantisation noise ratios with moderate complexity. TCM is replaced with turbo TCM (TTCM) and simulation results given which show that the new scheme can achieve the same performance as that possible using by trellis-coded scalar quantisation at an SNR slightly above the channel capacity bound 相似文献
19.
Gangxiang Shen Sanjay K. Bose Tee Hiang Cheng Chao Lu Teck Yoong Chai 《International Journal of Communication Systems》2001,14(4):407-418
The performance of WDM networks using shortest path routing is studied under wavelength continuous (WC) and non‐continuous (NWC) constraints and dynamic traffic loading. Approximate analytical models are presented for the performance studies of such systems. Results of numerical calculations based on these models and simulations are given for different network topologies for the purposes of comparison. These analytical and simulation results are used to study the performance of these WDM networks under dynamic traffic loading. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
20.
Meng Yew Tee Shuh Shing Lee 《International Journal of Computer-Supported Collaborative Learning》2013,8(3):313-331
Nonaka’s model of knowledge creation can provide guidance for designing learning environments and activities. However, Bereiter is critical of the model because it does not address whether understanding is deepened in the process of socialization, externalization, combination and internalization. To address this issue of understanding, this paper proposed a framework that synthesizes the basic phases of problem-based learning with Nonaka’s model. This paper reports on a study investigating if a course designed based on this authentic framework can help to stimulate knowledge creation based on deepening understanding. Several types of data were collected in this design-based research, namely: reflections by the participants and instructor; group discussions; student-created artifacts; and documents, records and artifacts that reflect the overall design of the course. The findings suggest that the participants demonstrated advancing understanding amidst knowledge creating conditions and processes consistent with Nonaka’s model. Other key implications are also discussed. 相似文献