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31.
With a growing emphasis on human identification, iris recognition has recently received increasing attention. Iris recognition includes eye imaging, iris segmentation, verification, and so on. In this letter, we propose a novel and efficient iris recognition method which employs a cumulative‐sum‐based grey change analysis. Experimental results demonstrate that the proposed method can be used for human identification in efficient manner. 相似文献
32.
Ravi Shanker Seungse Cho Ayoung Choe Minsoo P. Kim Ziyauddin Khan Saewon Kang Hyunhyub Ko 《Advanced functional materials》2019,29(39)
Flexible alternating‐current electroluminescent (ACEL) devices have attracted considerable attention for their ability to produce uniform light emission under bent conditions and have enormous potential for applications in back lighting panels, decorative lighting in automobiles, and panel displays. Nevertheless, flexible ACEL devices generally require a high operating bias, which precludes their implementation in low power devices. Herein, solution‐processed La‐doped barium titanate (BTO:La) nanocuboids (≈150 nm) are presented as high dielectric constant (high‐k) nanodielectrics, which can enhance the dielectric constant of an ACEL device from 2.6 to 21 (at 1 kHz), enabling the fabrication of high‐performance flexible ACEL devices with a lower operating voltage as well as higher brightness (≈57.54 cd m?2 at 240 V, 1 kHz) than devices using undoped BTO nanodielectrics (≈14.3 cd m?2 at 240 V, 1 kHz). Furthermore, a uniform brightness across the whole panel surface of the flexible ACEL devices and excellent device reliability are achieved via the use of uniform networks of crossaligned silver nanowires as highly conductive and flexible electrodes. The results offer experimental validation of high‐brightness flexible ACELs using solution‐processed BTO:La nanodielectrics, which constitutes an important milestone toward the implementation of high‐k nanodielectrics in flexible displays. 相似文献
33.
Sjolund O. Louderback D.A. Hegblom E.R. Ko J. Coldren L.A. 《Electronics letters》1998,34(18):1742-1743
Monolithic integration of high performance microlensed resonant photodetectors and vertical cavity lasers (VCLs) from a single epitaxial growth is presented. The VCLs have sub-200 μA threshold currents. Adjacent detectors have the same operating wavelength and responsivities of ~0.4 A/W with ~6 nm optical bandwidths 相似文献
34.
H. S. Kim D. H. Ko D. L. Bae N. I. Lee D. W. Kim H. K. Kang M. Y. Lee 《Journal of Electronic Materials》1998,27(4):L21-L25
We have investigated the thermal degradation of gate oxide in metal-oxide-semiconductor (MOS) structures with Ti-polycide
gates. We found that the Ti-diffusion into the underlying polysilicon and consequently to the gate oxide occurs upon thermal
cycling processes, which results in the dielectric breakdown of the gate oxide. We also found that the Ti-diffusion is suppressed
by the employment of the thin (about 5 nm) titanium nitride (TiN) diffusion barrier layer, which consequently improved the
reliability characterisitics of gate oxide significantly. 相似文献
35.
H. Krishna Garg C. C. Ko K. Y. Lin H. Liu 《Circuits, Systems, and Signal Processing》1996,15(4):437-452
In this work, we analyze the algebraic structure of fast algorithms for computing one- and two-dimensional convolutions of sequences defined over the fields of rational and complex rational numbers. The algorithms are based on factorization properties of polynomials and the direct sum property of modulo computation over such fields. Algorithms are described for cyclic as well as acyclic convolution. It is shown that under certain nonrestrictive conditions, all the previously defined algorithms over the fields of rational and complex rational numbers are also valid over the rings of finite integers. Examples are presented to illustrate the results. 相似文献
36.
Takuma Suzuki Hang-Ju Ko Agus Setiawan Jung-Jin Kim Koh Saitoh Masami Terauchi Takafumi Yao 《Materials Science in Semiconductor Processing》2003,6(5-6):519-521
We report the successful growth of Ga-polar GaN epilayers on O-polar ZnO templates pre-deposited on c-sapphire. Prior to GaN growth, NH3 is exposed onto the ZnO template. The polarity of the GaN layers is confirmed by etching of the surface and by conversion beam electron diffraction (CBED), while the O-polar ZnO is confirmed by CBED. It is suggested that the NH3 pre-exposure helps form a Zn3N2 layer, which possesses inversion symmetry and inverts the crystal from anion polar to cation polar. 相似文献
37.
Meng Yu Tsai Ko Chun Lee Che Yi Lin Yuan Ming Chang Kenji Watanabe Takashi Taniguchi Ching Hwa Ho Chen Hsin Lien Po Wen Chiu Yen Fu Lin 《Advanced functional materials》2021,31(40):2105345
In bionic technology, it has become an innovative process imitating the functionality and structuralism of human biological systems to exploit advanced artificial intelligent machines. Bionics plays a significant role in environmental protection, especially for its low energy loss. By fusing the concept of receptor-like sensing component and synapse-like memory, the photoactive electro-controlled optical sensory memory (PE-SM) is proposed and realized in a single device, which endows a simple methodology of reducing power consumption by photoactive electro-control. The PE-SM is the system built with the stacked atomically thick materials, in which rhenium diselenide serves as a robust photosensor, hexagonal boron nitride serves as a tunneling dielectric, and graphene serves as a charge-storage layer. With the features of the PE-SM, it performs synaptic metaplasticities under optical spikes. In addition, a simulated spiking neural network composed of 24 × 24 PE-SMs is further presented in an unsupervised machine learning environment, performing image recognition via the Hebbian rule. The PE-SM not only improves the neuromorphic computing efficiency but also simplifies the circuit-size structure. Eventually, the concept of photoactive electro-control can extend to other photosensitive 2D materials and provide a new approach of constructing either visual perception memory or photonic synaptic devices. 相似文献
38.
Do-Young Lee Se-Yeon Jeong Kyung-Chan Ko Jae-Hyoung Yoo James Won-Ki Hong 《International Journal of Network Management》2021,31(6):e2176
In 5G networks, it is necessary to provide services while meeting various service requirements, such as high data rates and low latency, in response to dynamic network conditions. Multi-access edge computing (MEC) is a promising concept to meet these requirements. The MEC environment enables service providers to deploy their low latency services that are composed of multiple components. However, operating a service manually and attempting to satisfy the quality of service (QoS) requirements is difficult because many factors need to be considered in an MEC scenario. In this paper, we propose an auto-scaling method using deep Q-networks (DQN), which is a reinforcement learning algorithm, to resize the number of instances assigned to service. In our evaluation, compared to other baseline methods, the proposed approach maintains the appropriate number of instances effectively in response to dynamic traffic change while satisfying QoS and minimizing the cost of operating the service in the MEC environment. The proposed method was implemented as a module running in OpenStack and published as open-source software. 相似文献
39.
Microstructure control of copper films by the addition of molybdenum in an advanced metallization process 总被引:2,自引:0,他引:2
W. H. Lee Y. K. Ko J. H. Jang C. S. Kim P. J. Reucroft J. G. Lee 《Journal of Electronic Materials》2001,30(8):1042-1048
The effect of annealing on the resistivity, morphology, microstructure, and diffusion characteristics of Cu(Mo)/SiO2/Si and Ti/Cu(Mo)/SiO2/Si multilayer films has been investigated in order to deterine the role of Mo. In the case of a Cu(Mo)/SiO2/Si multilayer, most of the Mo diffused out to the free surface to form MoO3 at temperatures up to 500 C, and complete dissociation of Mo occurred at higher temperatures. The segregation of Mo to the
external surface leads to Mo-free Cu films with extensive grain growth up to 20 times the original grain size and strong (111)
texture. In the case of a Ti/Cu(Mo)/SiO2/Si multilayer, a thin Ti film prohibits Cu agglomeration, out-diffusion of Mo, and diffusion of Cu into SiO2 at temperatures up to 750 C. Cu(Mo) grain growth was less extensive, but (111) fiber texturing was much stronger than in
the case of Cu(Mo)/SiO2/Si. In the current study, significant changes in microstructure, such as a strong (111) texture and abnormal grain growth,
have been obtained by adding Mo to Cu films when the films are annealed. 相似文献
40.
A simple model for the hot-electron degradation of MOSFET linear-current drive is developed on the basis of the reduction of the inversion-layer mobility due to the generation of interface states. The model can explain the observed dependence of the device hot-electron lifetime on the effective channel length and oxide thickness by taking into account both the relative nonscalability of the localized damage region and the dependence of the linear-current degradation on the effective vertical electric field E eff. The model is verified for deep-submicrometer non-LDD n-channel MOSFETs with L eff=0.2-1.5 μm and T ox=3.6-21.0 nm. From the correlation between linear-current and charge-pumping degradation, the scattering coefficient α, which relates the number of generated interface states to the corresponding amount of inversion-layer mobility reduction, can be extracted and its dependence on E eff determined. Using this linear-current degradation model, existing hot-electron lifetime prediction models are modified to account explicitly for the effects of L eff and T ox 相似文献