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31.
This paper describes a research approach based on the Actor-Network Theory (ANT) to interpret and understand the Korea’s strategy for the development of the ubiquitous city (u-city). Analyzing empirical materials from u-city development, this study traces and unpacks the interaction occurring around the u-city innovation and also identifies patterns of innovation, concentrating on negotiation and translation implementation. The findings imply that Korean approach has marginalized key issues relating to the development potential inherent in the combination of knowledge and technology and thus conflicts with broader development suggestions of participative design. Korean case reveals the essential role of participatory design in u-city development. U-city as a public utility should draw users’ perspectives, its design should be heavily grounded in users’ needs, and its design decisions should be based on a community consensus. 相似文献
32.
33.
The paper aims at the development of the wavelet neural network (WNN) based conservative meta-model that satisfies the constraint feasibility of approximate optimal solution. The WNN based constraint-feasible meta-model is formulated via exterior penalty method to optimally determine interconnection weights and dilation and translation coefficients in the network. Using Ackley’s path function, the approximation performance of WNN is first tested in comparison with BPN. The proposed approach of constraint feasibility is then verified through a ten-bar planar truss problem. For constrained approximate optimization, the structural design of a composite rotor blade is explored to support the proposed strategies. 相似文献
34.
Changwoo Lee Hyunkyoo Kang Keehyun Shin 《Journal of Mechanical Science and Technology》2010,24(5):1097-1103
The mathematical model for tension in a moving web by Shin [1] was extended by considering thermal strain due to temperature fluctuations in the drying of a roll-to-roll system. The extended model describes variations in tension and includes terms that represent the change of the Young’s Modulus, the thermal coefficient, and the thermal strain. In this paper, a new control scheme based on the extended model is proposed for mitigation of tension disturbances due to thermal strain in the drying process. Tension feedback control logic generally is not be applied due to the fact that register errors can be induced by speed alterations that help to compensate for tension disturbances. But in our approach, the thermal strain in the web is compensated for by means of velocity adjustments without adding extra register errors in the steady state. A computer simulation followed by an experimental validation was carried out to confirm the performance of the proposed method. The results show that the proposed model is useful for describing tension behavior and suggest that tension control logic improves control precision for the drying module of a roll-to-roll e-printing system. 相似文献
35.
This paper proposes a computationally efficient learning‐based super‐resolution algorithm using k‐means clustering. Conventional learning‐based super‐resolution requires a huge dictionary for reliable performance, which brings about a tremendous memory cost as well as a burdensome matching computation. In order to overcome this problem, the proposed algorithm significantly reduces the size of the trained dictionary by properly clustering similar patches at the learning phase. Experimental results show that the proposed algorithm provides superior visual quality to the conventional algorithms, while needing much less computational complexity. 相似文献
36.
Leon A. S. Tam K. W. Shin J. L. Weisner D. Schumacher F. 《Solid-State Circuits, IEEE Journal of》2007,42(1):7-16
This first generation of "Niagara" SPARC processors implements a power-efficient Chip Multi-Threading (CMT) architecture which maximizes overall throughput performance for commercial workloads. The target performance is achieved by exploiting high bandwidth rather than high frequency, thereby reducing hardware complexity and power. The UltraSPARC T1 processor combines eight four-threaded 64-b cores, a floating-point unit, a high-bandwidth interconnect crossbar, a shared 3-MB L2 Cache, four DDR2 DRAM interfaces, and a system interface unit. Power and thermal monitoring techniques further enhance CMT performance benefits, increasing overall chip reliability. The 378-mm2 die is fabricated in Texas Instrument's 90-nm CMOS technology with nine layers of copper interconnect. The chip contains 279 million transistors and consumes a maximum of 63 W at 1.2 GHz and 1.2 V. Key functional units employ special circuit techniques to provide the high bandwidth required by a CMT architecture while optimizing power and silicon area. These include a highly integrated integer register file, a high-bandwidth interconnect crossbar, the shared L2 cache, and the IO subsystem. Key aspects of the physical design methodology are also discussed 相似文献
37.
In‐Hwan Ahn Seon Ju Yeo Kinam Jung Gumin Kang Dong‐Hun Shin Ho Seong Jang Byunghoon Kim Minwoo Nam Seok Joon Kwon Doo‐Hyun Ko 《Advanced functional materials》2020,30(13)
Upconversion nanoparticles (UCNPs) have been integrated with photonic platforms to overcome the intrinsically low quantum efficiency limit of upconversion luminescence (UCL). However, platforms based on thin films lack transferability and flexibility, which hinders their broader and more practical application. A plasmonic structure is developed that works as a multi‐functional platform for flexible, transparent, and washable near‐infrared (NIR)‐to‐visible UCL films with ultra‐strong UCL intensity. The platform consists of dielectric microbeads decorated with plasmonic metal nanoparticles on an insulator/metal substrate. Distinct improvements in NIR confinement, visible light extraction, and boosted plasmonic effects for upconversion are observed. With weak NIR excitation, the UCL intensity is higher by three orders of magnitude relative to the reference platform. When the microbeads are organized in a square lattice array, the functionality of the platform can be expanded to wearable and washable UCL films. The platform can be transferred to transparent, flexible, and foldable films and still emit strong UCL with a wide viewing angle. 相似文献
38.
Multicast is a scalable solution for group communications. In order to offer security for multicast applications, a group
key has to be changed whenever a member joins or leaves the group. This incurs 1-affects-n problem, which is a constraint on scalability. Decentralized approaches solve the scalability problem by dividing a group
into several subgroups that use independent group keys. These approaches, however, introduce new challenges: problem of trusting
third party and inefficiency of data delivery. Proxy encryption is a good approach to solve the problem of trusting third
party. In this paper, we propose a novel secure multicast scheme using the proxy cryptography. The proposed scheme provides
not only scalability but also data transmission efficiency by dynamic subgrouping of group members while intermediate data-relaying
third parties are not required to be trusted. 相似文献
39.
Ickjin Kwon Minkyu Je Kwyro Lee Hyungcheol Shin 《Microwave Theory and Techniques》2002,50(6):1503-1509
A simple and accurate parameter-extraction method of a high-frequency small-signal MOSFET model including the substrate-related parameters and nonreciprocal capacitors is proposed. Direct extraction of each parameter using a linear regression approach is performed by Y-parameter analysis on the proposed equivalent circuit of the MOSFET for high-frequency operation. The extracted results are physically meaningful and good agreement has been obtained between the simulation results of the equivalent circuit and measured data without any optimization. Also, the extracted parameters, such as gm and gds, match very well with those obtained by DC measurement 相似文献
40.
Younggeun Lee Jinhyeong Kwon Jaemook Lim Wooseop Shin Sewoong Park Eunseung Hwang Jaeho Shin Hyunmin Cho Jinwook Jung Hyun-Jong Kim Seungyong Han Habeom Lee Yong Son Cheol Woo Ha Prem Prabhakaran Junyeob Yeo Seung Hwan Ko Sukjoon Hong 《Advanced functional materials》2021,31(1):2006854
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