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排序方式: 共有2820条查询结果,搜索用时 15 毫秒
41.
42.
We study quantum teleportation between two different types of optical qubits using hybrid entanglement as a quantum channel under decoherence effects. One type of qubit employs the vacuum and single-photon states for the basis, called a single-rail single-photon qubit, and the other utilizes coherent states of opposite phases. We find that teleportation from a single-rail single-photon qubit to a coherent-state qubit is better than the opposite direction in terms of fidelity and success probability. We compare our results with those using a different type of hybrid entanglement between a polarized single-photon qubit and a coherent state. 相似文献
43.
Seung Jin Chang Jae Young Lee Jin Bae Park Yoon Ho Choi 《International Journal of Control, Automation and Systems》2015,13(2):311-318
In this paper, we propose an actor-critic neuro-control for a class of continuous-time nonlinear systems under nonlinear abrupt faults, which is combined with an adaptive fault diagnosis observer (AFDO). Together with its estimation laws, an AFDO scheme, which estimates the faults in real time, is designed based on Lyapunov analysis. Then, based on the designed AFDO, a fault tolerant actor- critic control scheme is proposed where the critic neural network (NN) is used to approximate the value function and the actor NN updates the fault tolerant policy based on the approximated value function in the critic NN. The weight update laws for critic NN and actor NN are designed using the gradient descent method. By Lyapunov analysis, we prove the uniform ultimately boundedness (UUB) of all the states, their estimation errors, and NN weights of the fault tolerant system under the unpredictable faults. Finally, we verify the effectiveness of the proposed method through numerical simulations. 相似文献
44.
Geun Bum Koo Jin Bae Park Young Hoon Joo 《International Journal of Control, Automation and Systems》2013,11(6):1075-1083
In this paper, a novel intelligent digital redesign (IDR) technique using the guaranteed cost control method is proposed for nonlinear systems which can be represented by a Takagi-Sugeno (T-S) fuzzy model. The IDR technique, which is one of the sampled-data fuzzy controller design methods, guarantees not only the stability condition of the sampled-data closed-loop system with the sampleddata fuzzy controller and the state-matching error is presented. By using the concept of the guaranteed cost control method, sufficient conditions are obtained for both minimization of the state-matching error and stabilization of the sampled-data closed-loop system and derived in terms of linear matrix inequalities (LMIs). Finally, a numerical example is provided to verify the effectiveness of the proposed technique. 相似文献
45.
Young-Hun Lim Myung-Eui Song Won-Hee Lee Hui-Je Cho Dae-Sung Bae 《Multibody System Dynamics》2009,22(2):145-162
The paper proposes a multibody dynamic simulation to numerically evaluate the generated axial force (GAF) and plunging resistant
force (PRF) practically related to the shudder and idling vibration of an automobile. A numerical analysis of the drive shaft
coupling of a ball joint (BJ) and two plunging type joints, a tripod joint (TJ), and a very low axial force tripod joint (VTJ),
are conducted using the commercial program DAFUL. User-defined subroutines of a friction model illustrating the contacted
parts of the outboard and inboard joint are subsequently developed to overcome the numerical instability and improve the solution
performance. The Coulomb friction effect is applied to describe the contact models of the lubricated parts in the rolling
and sliding mechanisms. The numerical results, in accordance with the joint articulation angle variation, are validated with
experimentation. The offset between spider and housing is demonstrated to be the critical role in producing the third order
component of the axial force that potentially causes the noise and vibration in the vehicle. The VTJ shows an excellent behavior
for the shudder when compared with the TJ. In addition, a flexible nonlinear contact analysis coupled with multibody dynamics
is also performed to show the dynamic strength characteristics of the rollers, housing, and spider. 相似文献
46.
Feng Feng Young Bae Jun 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(11):1113-1121
The notion of an inductive semimodule over an ordered *-semiring is introduced and some related properties are investigated.
Inductive semimodules are extensions of several important algebraic structures such as Kleene modules, Kleene algebras and
inductive *-semirings. We prove that an inductive semimodule over an ordered *-semiring K is a Kleene module if and only if K is a Kleene algebra. Moreover, we establish that the vector module of an inductive semimodule over an ordered Conway semiring
is again an inductive semimodule over the matrix semiring. Consequently, in an inductive semimodule over an ordered Conway
semiring, least solutions to linear inequation systems can be denoted by linear expressions, avoiding the least fixed point
operator. In addition, we also introduce a related notion called weak inductive semimodules, and propose several open problems
on them.
相似文献
Young Bae JunEmail: |
47.
Y. H. Bae A. I. Lyakhov V. M. Vishnevsky K. J. Kim B. D. Choi 《Automation and Remote Control》2008,69(3):529-543
In this paper, we estimate characteristics of the IEEE 802.11 DCF (Distributed Coordination Function) in non-saturation mode. We take into account two significant features inherent to the non-saturated 802.11 DCF: (i) the possibility of asynchronous transmission performed without preceding backoff for the first packet arriving at the idle staion; and (ii) so-called post backoff meaning that a station must perform a backoff once after any of its transmissions even if its queue becomes empty. We derive the probability generating function (PGF) of Head-of-Line delay (HoL-delay). Our method to find PGF of HoL-delay is quite intuitive and straightforward. Also, we obtain the packet loss probability and non-saturation throughput. Numerical results show that these two features inherent to the non-saturated 802.11 DCF influence on the performance measures of DCF such as delay considerably and it should be taken into account for accurate modeling of DCF. 相似文献
48.
Soojeong Choi Jihoon Jeon Yunsu Bae Yongsoon Hwang Seung-Woo Cho 《Advanced functional materials》2023,33(44):2303043
Oral disease is one of the most common conditions worldwide, negatively affecting general health, reducing the quality of life, and often developing into systemic illness. However, the design of therapeutic agents for oral diseases is challenging due to various unique features of the oral cavity, including its wet and dynamic environment and curved shape. Herein, the development of highly biocompatible mucoadhesive functional hydrogels for oral applications is reported, generated by introducing bio-inspired phenolic moieties into a pectin polymer. Pyrogallol-functionalized pectin (Pec-PG) can be crosslinked in situ via autoxidation without chemical agents and readily fabricated as various formulations. Sprayable Pec-PG hydrogel exhibits strong mucoadhesion and outstanding hydration ability ex vivo and in vivo, thus displaying significant potential as a novel saliva substitute for dry mouth. The authors further show that topical application of mucoadhesive Pec-PG patches pre-loaded with corticosteroid significantly promotes the repair of diabetic oral ulcer tissue via prolonged drug release, free radical scavenging, and physical barrier effects. Moreover, similar applications for oral ulcer treatment using a pectin hydrogel modified with catechol (Pec-CA), another phenolic moiety are demonstrated. Together, these findings suggest that mucoadhesive phenolic pectin derivatives can provide highly biocompatible, convenient, and effective hydrogel platforms for treating oral diseases. 相似文献
49.
Min Seong Kim Yung Lee Junseong Ahn Seonggi Kim Kyungnam Kang Hyuneui Lim Byeong-Soo Bae Inkyu Park 《Advanced functional materials》2023,33(3):2208792
Conventional elastomeric polymers used as substrates for wearable platforms have large positive Poisson's ratios (≈0.5) that cause a deformation mismatch with human skin that is multidirectionally elongated under bending of joints. This causes practical problems in elastomer-based wearable devices, such as delamination and detachment, leading to poorly reliable functionality. To overcome this issue, auxetic-structured mechanical reinforcement with glass fibers is applied to the elastomeric film, resulting in a negative Poisson's ratio (NPR), which is a skin-like stretchable substrate (SLSS). Several parameters for determining the materials and geometrical dimensions of the auxetic-structured reinforcing fillers are considered to maximize the NPR. Based on numerical simulation and digital image correlation analysis, the deformation tendencies and strain distribution of the SLSS are investigated and compared with those of the pristine elastomeric substrate. Owing to the strain-localization characteristics, an independent strain-pressure sensing system is fabricated using SLSS with a Ag-based elastomeric ink and a carbon nanotube-based force-sensitive resistor. Finally, it is demonstrated that the SLSS-based sensor platform can be applied as a wearable device to monitor the physical burden on the wrist in real time. 相似文献
50.
Jangwon Moon Junwoo Kim Hoon Lee Youngjin Moon Yongsu Lee Youngjo Bang Kyungyeol Sohn Jungsook Bae Kwangseon Kim Seungjae Bahng Heesoo Lee 《ETRI Journal》2023,45(5):781-794
Uncrewed aerial vehicles (UAVs) have become a vital element in nonterrestrial networks, especially with respect to 5G communication systems and beyond. The use of UAVs in support of 4G/5G base station (uncrewed aerial vehicle base station [UAV-BS]) has proven to be a practical solution for extending cellular network services to areas where conventional infrastructures are unavailable. In this study, we introduce a UAV-BS system that utilizes a high-capacity wireless backhaul operating in millimeter-wave frequency bands. This system can achieve a maximum throughput of 1.3 Gbps while delivering data at a rate of 300 Mbps, even at distances of 10 km. We also present the details of our testbed implementation alongside the performance results obtained from field tests. 相似文献