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111.
W. H. Lee C. C. Yu S. H. Tung 《The Structural Design of Tall and Special Buildings》2006,15(3):233-247
A preliminary study of the ‘displacement‐based strength reduction factor’ for high‐rise steel moment‐resisting frames is presented in this paper. The base shear capacity required for a high‐rise steel building in a displacement‐based design can be estimated from the reduction of the displacement‐based elastic response. The conventional force‐based design procedure is still adopted as the initial stage of the displacement‐based design. To establish an empirical formula of the proposed displacement‐based strength reduction factor, non‐linear time‐history analyses of six moment‐resisting frames are investigated. The conventional ‘equal displacement rule’ and ‘equal energy rule’ are no longer held when the displacement limitations are considered. As a result, a modification for conventional strength reduction factors is proposed for further applications in displacement‐based design. An adjustment factor defined as ‘deformation energy ratio’, β, which is related to natural periods, is introduced. The final displacement‐based strength reduction factor is defined as a function of ductility demand, fundamental period and the deformation energy ratio. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
112.
Thirty-one of 104 clinical isolates of Klebsiella pneumoniae collected over a period of 8 months were found to be putative extended-spectrum beta-lactamase (ESBL) producers. Isoelectric focusing and an iodine overlay agar method were used for preliminary identification of the ESBLs. They were further identified by DNA sequencing. Seventy-one percent of the isolates were found to produce SHV-5. The variation in the ESBL patterns of these isolates was slight, with only five patterns being identified. The strains were typed by pulsed-field gel electrophoresis (PFGE), and 16 different genotypes were identified. When the PFGE patterns were analyzed by the algorithmic clustering method called the unweighted-pair group method using arithmetic averages, five clusters were found. However, significant genetic variations were found among 11 isolates and between each cluster. A plasmid of 36 kb was found in all clinical isolates and in the transconjugants. Our results indicate that the increase in the number of ESBL-producing K. pneumoniae isolates in this hospital is due mainly to the dissemination of a resistance plasmid rather than to the clonal spread of a few epidemic strains. 相似文献
113.
Ren C. Yu H.Y. Wang X.P. Ma H.H.H. Chan D.S.H. Li M.-F. Yee-Chia Yeo Tung C.H. Balasubramanian N. Huan A.C.H. Pan J.S. Kwong D.-L. 《Electron Device Letters, IEEE》2005,26(2):75-77
In this letter, we study Terbium (Tb)-incorporated TaN (TaTb/sub x/N) as a thermally robust N-type metal gate electrode for the first time. The work function of the Ta/sub 0.94/Tb/sub 0.06/N/sub y/ metal gate is determined to be /spl sim/4.23 eV after rapid thermal anneal at 1000/spl deg/C for 30 s, and can be further tuned by varying the Tb concentration. Moreover, the TaTb/sub x/N-SiO/sub 2/ gate stack exhibits excellent thermal stability up to 1000/spl deg/C with no degradation to the equivalent oxide thickness, gate leakage, and time-dependent dielectric breakdown (TDDB) characteristics. These results suggest that Tb-incorporated TaN (TaTb/sub x/N) could be a promising metal gate candidate for n-MOSFET in a dual-metal gate Si CMOS process. 相似文献
114.
Tung S. P. 《Information and Computation》1995,120(2)
Arithmetical sentences are the sentences containing usual logical symbols and arithmetical symbols +, ·, and constants of Z. An arithmetical sentence φ is called an sentence if and only if φ is logically equivalent to a sentence of the form x yψ(x, y) where ψ(x, y) is a quantifier free formula. It is shown that the decision problems of determining sentences true in N or Z, respectively, are co-NP-complete, whereas the decision problem of determining sentences true in Q is in P. Consequently, the decision problems of determining sentences true in N or Z, respectively, are NP-complete. Also, the decision problem of determining sentences true in Q is in P. 相似文献
115.
Tung Chong Wong Mark J.W. Kee-Chaing Chua 《Selected Areas in Communications, IEEE Journal on》2003,21(10):1536-1545
An approximate analytical formulation of the resource allocation problem for handling variable bit rate multiclass services in a cellular direct sequence code-division multiple-access (DS-CDMA) system is presented. The novelty in this paper is that all grade-of-service (GoS) or quality-of-service (QoS) requirements at the connection level, packet level, and link layer are satisfied simultaneously, instead of being satisfied at the connection level or at the link layer only. The analytical formulation shows how the GoS/QoS in the different layers are intertwined across the layers. A complete sharing (CS) scheme with guard channels is used for the resource sharing policy at the connection level. The CS model is solved using a K-dimensional Markov chain. Numerical results illustrate that significant gain in system utilization is achieved through the joint coupling of connection/packet levels and link layer. This can translate to more revenues for network providers and/or lower charges for mobile users. 相似文献
116.
Self-organized Ge/Si quantum dots (QD's) in strained Si/Ge short-period superlattices are studied by Raman scattering under hydrostatic pressure excited in-resonance and off-resonance with the confined Ge-like E1 transition of Ge using 488 and 514.5 nm lines from an argon-ion laser and 632.8 nm line from a He-Ne laser. The Raman spectra of Ge-Ge, Si-Ge and Si-2TA modes of the QD's were obtained as a function of pressure in the range of 1-70 kbar. Our results show that the mode Grüneisen parameter of the Ge-Ge phonon mode in QD's is found to be γ=0.81±0.01, which is smaller than that of the bulk Ge. We observe resonance effects with the confined Ge-like E1 transition and the pressure coefficient of this resonating electronic transition obtained is ∼5±1 meV kbar−1. 相似文献
117.
Davis James H.; Hulbert Lorne; Au Wing Tung; Chen Xiao-ping; Zarnoth Paul 《Canadian Metallurgical Quarterly》1997,73(4):703
Six-person mock civil juries awarded significantly larger amounts for damages than did 12-person juries, and individuals preferred even larger average awards. A reversal of the "deep-pockets bias" observed earlier, an explanation involving temporal fluctuation in normative standards, during the time interval between the studies, was supported by independent data showing temporal trends in actual civil trial awards. A computational model of consensus that assumed a strong majority of those members with the most similar (closest) personal preferences decided on the median of their preferences accurately predicted award magnitude. Computer simulations explored the effects of critical faction size (majority, etc.) and location within the group, features that might in turn depend on task environment, cultural dynamics, and social context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
J. F. Davis Hsien-Hsin Tung R. S. H. Mah 《American Institute of Chemical Engineers》1984,30(2):328-338
A model is presented to describe the behavior of falling film fractionators with evaporation or condensation. Experimental measurements of vapor composition, vapor temperature and wall temperature profiles were made. Close agreement suggests that the model is applicable to both adiabatic and nonadiabatic conditions. 相似文献
119.
SJ Freedman DF Geesaman R Gilman MC Green RJ Holt HE Jackson ER Kinney R Kowalczyk C Marchand J Napolitano J Nelson DH Potterveld B Zeidman RE Segel T Tung D Beck G Boyd D Collins BW Filippone CE Jones J Jourdan RD McKeown R Milner R Walker PE Bosted Z Meziani R Minehart 《Canadian Metallurgical Quarterly》1993,48(4):1864-1878
120.
The organization and operation of a semantic network array processor (SNAP) are described. The architecture consists of an array of identical cells each containing a content addressable memory, microprogram control, and communication unit. Each cell is dedicated to one node of the semantic network and its associated relations. The array can perform global associative functions under the supervision of an outside controller. In addition, each-cell is equipped with the necessary logic to perform individual functions. A set of primitive instructions was carefully chosen. Some of the applications discussed include pattern search operations, production systems, and inferences. A LISP simulator was developed for this architecture, and some simulation results are presented. 相似文献