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排序方式: 共有416条查询结果,搜索用时 15 毫秒
41.
Ping-Hung Tsai Kuei-Shu Chang-Liao Chu-Yung Liu Tien-Ko Wang Tzeng P.J. Lin C.H. Lee L.S. Tsai M.-J. 《Electron Device Letters, IEEE》2008,29(3):265-268
Operation properties of polysilicon-oxide-nitride-oxide-silicon-type Flash device with HfAlO charge-trapping layer having various Al contents were investigated in this letter. Satisfactory performance in terms of operation speed, retention, and program/erase endurance of the Flash device is achieved with the optimal Al content of 18%-28% in the HfAlO trapping layer. In addition, high-speed operation can be attained with the combination of channel-hot-electron-injection programming and band-to-band hot hole erasing for NOR architecture applications. 相似文献
42.
43.
Characterization of the Ultrathin HfO2 and Hf-Silicate Films Grown by Atomic Layer Deposition 总被引:1,自引:0,他引:1
Tze Chiang Chen Cheng-Yi Peng Chih-Hung Tseng Ming-Han Liao Mei-Hsin Chen Chih-I Wu Ming-Yau Chern Pei-Jer Tzeng Chee Wee Liu 《Electron Devices, IEEE Transactions on》2007,54(4):759-766
The physical properties of HfO2 and Hf-silicate layers grown by the atomic layer chemical vapor deposition are characterized as a function of the Hf concentration and the annealing temperature. The peaks of Fourier transform infrared spectra at 960, 900, and 820 cm-1 originate from Hf-O-Si chemical bonds, revealing that a Hf-silicate interfacial layer began to form at the HfO2/SiO 2 interface after post deposition annealing process at 600 degC for 1 min. Moreover, the intensity of the peak at 750 cm-1 can indicate the degree of crystallization of HfO2. The formed Hf-silicate layer between HfO2 and SiO2 is also confirmed by X-ray photoelectron spectroscopy 相似文献
44.
Agazzi O. Chin-Pyng Tzeng Messerschmitt D. Hodges D. 《Communications, IEEE Transactions on》1985,33(6):558-569
Tradeoffs in the design of the timing recovery functions in a subscriber loop receiver are analyzed. The techniques considered are applicable to both the echo cancellation (EC) and time compression multiplexing (TCM) methods of full duplex transmission. Emphasis is on those techniques that lend themselves to implementation in MOSLSI technology, where the objective requirement is that timing recovery be implemented on a sampled-data signal (with the minimum possible sampling rate where EC is used). The wave difference method (WDM) for timing recovery appears to be the best candidate. A detailed study of its performance is carried out analytically and by computer simulation for the case of binary and alternate mark-inversion (AMI) line coding. A closed form expression describing the binary jitter performance of the WDM and its continuous time counterpart, the spectral line technique, is used to compare the two techniques. Analytical and simulation results for recovered phase and jitter are presented for various cable pulse responses carefully chosen to represent worst-case or nearly worst-case conditions. Two methods for including frequency detection in the WDM, the quadricorrelator and the rotational detector, are also simulated. 相似文献
45.
Using Nonadditive Fuzzy Integral to Assess Performances of Organizational Transformation Via Communities of Practice 总被引:1,自引:0,他引:1
Chu M.-T. Shyu J. Z. Tzeng G.-H. Khosla R. 《Engineering Management, IEEE Transactions on》2007,54(2):327-339
Organizational transformations have been widely adopted by firms who wish to improve their competitive advantage to be better prepared to face external challenges. This research has chosen Communities of Practice (CoPs) as the subject of discussion for an assessment model to reform organizations that undertake CoPs for collective knowledge to enhance their core competencies. Given the interrelationships between criteria, this research uses the nonadditive fuzzy integral to develop a framework for the CoPs performance assessment. The purposes of this paper are to identify the key dimensions/criteria in the CoPs, to use fuzzy logic method to analyze the relative importance of each criterion, and to rank the criteria so that proper resources can be allocated while managing the CoPs. Through interviews with experts, four strategy alternatives and 16 criteria along four dimensions are generated. A survey of the CoPs practitioners is then conducted to compare the results of each criterion. The results will not only help organizations that intend to initiate changes via the CoPs activities to decide the ranking of their appraisal criteria, but it can also assist them in guiding the behavior of their staff while effectively monitoring and improving the performances of the CoPs 相似文献
46.
Acoustic speed is an important parameter that can be used to characterize bone tissue for evaluation of osteoporosis. Traditional approaches for measuring acoustic speed require knowledge of either the specimen thickness, which is sometimes difficult to obtain from biological tissues, or the reference fluid velocity that, moreover, is an unknown parameter for internal tissue in in vivo measurement. In this paper, a new method is proposed to measure acoustic speed from dual reflected ultrasound signals. This technique utilizes two transducers placed on the same side of the test object; one for transmitter and receiver, and the other one for receiver only. The acoustic speed of the test object is based on the information of time-of-flight from the signals received by both transducers and the separation distance between the transducer pair. The technique developed here not only eliminates the requirement of knowledge of specimen thickness, but also shows a feasibility for clinical applications. The results of different porcine and bovine bone samples measured in vitro by this technique are in good agreement with those measured by other published methods. In vivo measurement results of 10 healthy young volunteers' tibias are also reported. 相似文献
47.
The performance of a 3.4-Gb/s system using a low-power 1.318- mu m distributed-feedback (DFB) laser transmitter and a traveling-wave semiconductor laser power amplifier is studied. The -14.5-dBm, input from a directly modulated DFB laser is boosted to +10.3 dBm, of which +4.8 dBm is coupled into the transmission fiber. The penalty, caused by amplifier noise and pattern effects due to gain saturation, is less than 0.5 dB.<> 相似文献
48.
The role of intracellular thiols in menadione-mediated toxicity was studied in neonatal rat cardiomyocytes. The sensitivity of cardiomyocytes to menadione was greater than that of skeletal muscle cells and 3T3 fibroblasts. Before cell degeneration, menadione induced marked depletion of intracellular thiols and an increase of oxidized glutathione. The sensitivity of these cells to menadione correlated with the level of depletion of intracellular thiols. After incubation of cardiomyocytes with menadione, glutathione reductase activity was inhibited and lipid peroxidation was increased. Both dicumarol (an inhibitor of DT-diaphorase) and diethyldithiocarbamate (an inhibitor of superoxide dismutase) enhanced the capacity of menadione to induce cellular damage and to cause depletion of intracellular glutathione. Decreasing intracellular glutathione by pretreatment of cells with N-ethylmaleimide or buthionine sulphoximine also increased menadione-induced cell degeneration. Preincubation with cysteine or dithiothreitol suppressed the capacity of menadione to damage the cells. Menadione-induced lipid peroxidation was also suppressed by the same treatment. These results show that the oxidative stress induced by menadione in cardiomyocytes results in the depletion of glutathione and protein thiols. Both DT-diaphorase and superoxide dismutase can protect cells from the toxicity of menadione. Cellular thiols are determinants of the responsiveness to menadione. 相似文献
49.
K.Y. Lin S.H. Hsieh H.P. Tserng K.W. Chou H.T. Lin C.P. Huang K.F. Tzeng 《Advanced Engineering Informatics》2008,22(3):350-361
The increasing importance of text-based information retrieval (IR) developments in the architecture, engineering, and construction industries (AEC) and the lack of sharable testing resources to support these developments call for an approach that can be used to generate domain-specific reference collections. To address this need, the authors investigated the characteristics of the testing environment in AEC and ways to adapt dominant collection preparation methods for the domain. This paper presents the authors’ collection generation approach through the preparation process of the Taiwanese National Center for Research on Earthquake Engineering (NCREE) collection. The collection’s Chinese-to-English translation instruments are also discussed as matching semantic/linguistic resources are highly valued in AEC’s text-based IR developments. The paper also includes a use case for the NCREE collection to show how a collection generated by the proposed approach could be applied to support research experiment and validation. The direct outputs, the NCREE collection and its translation instruments, are sharable and reusable testing resources, while mechanisms for seeking collections from other researchers are part of the extended research endeavors. 相似文献
50.
The basic behavior of the shear deformation plate theories derived from the recently proposed Reissner's and Jing-Liao's functionals is studied in this paper. The difference between these two functionals is on the energy form of transverse normal stress. In Reissner's functional, the transverse normal stress has to be assumed as well as displacements and transverse shear. On the other hand, the independent variables in Jing-Liao's functional include only displacements and transverse shear. The comparison of these functionals is made through two examples, one with assumed transverse normal stress and the other without. It is found that for the cases studied in this paper Jing-Liao's functional provides a simpler, sometimes even better, alternative approach than Reissner's functional in formulating shear deformation theory of thick plates. 相似文献