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A distribution-free tabular CUSUM chart for autocorrelated data 总被引:1,自引:0,他引:1
Seong-Hee Kim Christos Alexopoulos Kwok-Leung Tsui James R. Wilson 《IIE Transactions》2007,39(3):317-330
A distribution-free tabular CUSUM chart called DFTC is designed to detect shifts in the mean of an autocorrelated process. The chart's Average Run Length (ARL) is approximated by generalizing Siegmund's ARL approximation for the conventional tabular CUSUM chart based on independent and identically distributed normal observations. Control limits for DFTC are computed from the generalized ARL approximation. Also discussed are the choice of reference value and the use of batch means to handle highly correlated processes. The performance of DFTC compared favorably with that of other distribution-free procedures in stationary test processes having various types of autocorrelation functions as well as normal or nonnormal marginals. 相似文献
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Wei-Hao Wu Bing-Yue Tsui Mao-Chieh Chen Yong-Tian Hou Yin Jin Tao H.-J. Shih-Chang Chen Mong-Song Liang 《Electron Devices, IEEE Transactions on》2007,54(6):1330-1337
Transient charging and discharging of border traps in the dual-layer HfO2/SiO2 high-kappa gate stack have been extensively studied by the low-frequency charge pumping method with various input pulse waveforms. It has been demonstrated that the exchange of charge carriers mainly occurs through the direct tunneling between the Si conduction band states and border traps in the HfO2 high-kappa dielectric within the transient charging and discharging stages in one pulse cycle. Moreover, the transient charging and discharging behaviors could be observed in the time scale of 10-8- 10-4 s and well described by the charge trapping/detrapping model with dispersive capture/emission time constants used in static positive bias stress. Finally, the frequency and voltage dependencies of the border trap area density could also be transformed into the spatial and energetic distribution of border traps as a smoothed 3-D mesh profiling 相似文献
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C.Y. Tang P.S. Uskokovic C.P. Tsui Dj. Veljovic R. Petrovic Dj. Janackovic 《Ceramics International》2009
The aim of the study was to investigate the influence of microstructure and phase composition on the mechanical behaviour of hydroxyapatite (HAp) and biphasic HAp/β-tricalcium phosphate (β-TCP) bioceramic materials using nanoindentation. The formation of β-TCP phase in the HAp ceramic had the predominant influence on the nanomechanical properties of compact ceramics. For investigated microstructures there appear to be a slight decrease in the elastic modulus with increasing load and a higher decrease in hardness, which are in agreement with upper bounds of the results reported in literature. Maximal value of reduced modulus and hardness is yielded with pure HAp, and is measured to be 133.76 GPa for average grain size of 3 μm and 12.18 GPa for average grain size of 140 nm, respectively. The average modulus and hardness results for HAp/β-TCP ceramics with higher (101.61 GPa, 6.76 GPa) and lower grain size (115.72 GPa, 8.76 GPa) show sufficient mechanical properties in order to serve as hard tissue replacement material. 相似文献
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IMPACT MODELS FOR SITING UNDESIRABLE FACILITIES 总被引:1,自引:0,他引:1
Alan T. Murray Richard L. Church Ross A. Gerrard Wing-Sing Tsui 《Papers in Regional Science》1998,77(1):19-36
ABSTRACT Location models continue to be recognized as valuable tools for providing insights to decision makers regarding the impacts and relative attributes of potential planning alternatives. An important area of current location modeling research has been devoted to issues associated with siting undesirable facilities. A number of approaches for addressing equity and community impact in locating these facilities are reviewed and developed in this article. Application results for the planning models presented in this article demonstrate their relative benefits and solution characteristics. 相似文献