http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Yongchao (검색결과 54 건)
- 무료
- 기관 내 무료
- 유료
-
Theoretical formulation for vehicle-bridge interaction analysis based on perturbation method
Yongchao Tan,Liang Cao,Jiang Li 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.82 No.2
A three-mass vehicle model including one rigid mass and two unsprung masses is adopted to predict the vehicle-bridge interaction (VBI) and to establish the nonlinear coupled governing equations. To overcome the numerical instability and large computation problems concerning the vehicle-bridge system, the perturbation method is used to convert the nonlinear coupled governing equations into a set of linear uncoupled equations. Formulas for bridge’s natural frequencies considering both the VBI and the dynamic responses of bridge and vehicle are proposed. Compared with the numerical results obtained by the Newmark-β method, the theoretical solutions for natural frequencies and dynamic responses are validated. The effects of the important factors of unsprung mass, vehicle damping, surface irregularity on the natural frequencies and dynamic responses of bridge and vehicle are discussed, based on the theoretical solutions.
-
Yongchao Liu,Qidan Zhu,Lipeng Wang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2
This article focuses on designing a robust adaptive fuzzy asymptotic control method for uncertain switched nonlinear systems in presence of arbitrary switching signals. The unknown dynamics of switched systems are addressed by making use of fuzzy logic systems. Different from the existing approximation-based schemes, the asymptotic tracking performance is achieved by employing a bound estimation method, some smooth functions and the backstepping technique. Through constructing Lyapunov function, the devised scheme can guarantee the stability and asymptotic convergence character of the controlled systems. Finally, the availability of the presented approach is verified via simulation examples.
-
Analysis of Blue Honeysuckle Binding Force During Harvest Period
Yongchao Zhao,Degang Kong,Junwei Huo 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.8
The purpose of this study is to understand the characteristics of proper binding force to harvest blue honeysuckle. After tracking such force over 16 days for four breeds of blue honeysuckle during the harvest period, we find that the binding force is mainly distributed in the range of 0.1 ~ 1.7N (P<0.05). This distribution range varies slightly between breeds: the picking forces of L.caerulea subsp.altaicai and Berel are greater than Bluebird and wild L.caerulea var.edulis of Changbai Mountain, and the binding forces of all breeds decrease over time with different slopes. Moreover, we also find that the binding force in the afternoon are significant larger than in the morning for the same day (P<0.05), and no significant difference is found between sunny and rainy days. We categorize factors affecting the binding force, such as testing day, morning and afternoon, relative humidity, temperature, weather conditions into environmental factors and time factor.
-
A 2-D simulation study on CO2 soluble surfactant for foam enhanced oil recovery
Yongchao Zeng,Rouhi Farajzadeh,Sibani L. Biswal,George J. Hirasaki 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.72 No.-
This paper probes the transport of CO2 soluble surfactant for foaming in porous media. We numericallyinvestigate the effect of surfactant partitioning between the aqueous phase and the gaseous phase onfoam transport for subsurface applications when the surfactant is injected in the CO2 phase. A 2-Dreservoir simulation is developed to quantify the effect of surfactant partition coefficient on thedisplacement conformance and CO2 sweep efficiency. A texture-implicit local-equilibrium foam model isembedded to describe how the partitioning of surfactant between water and CO2 affects the CO2 foammobility control when surfactant is injected in the CO2 phase. We conclude that when surfactant hasapproximately equal affinity to both the CO2 and the water, the transport of surfactant is in line with thegas propagation and therefore the sweep efficiency is maximized. Too high affinity to water (smallpartition coefficient) results in surfactant retardation whereas too high affinity to CO2 (large partitioncoefficient) leads to weak foam and insufficient mobility reduction. This work sheds light upon the designof water-alternating-gas-plus-surfactant-in-gas (WAG + S) process to improve the conventional foamprocess with surfactant-alternating-gas (SAG) injection mode during which significant amount ofsurfactant could possibly drain down by gravity before CO2 slugs catch up to generate foam in situ thereservoir.
-
Yongchao Wang,Kuangang Fan,Qishou Pang 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.4
In suspended permanent magnet maglev trains, the magnetic field generated by hollow-type permanent magnet synchronous linear motors is one of the main sources of low-frequency electromagnetic fields. To investigate the magnetic field generated by the linear motor in the train, this paper first establishes the 2D and 3D models of the linear motor using ANSYS electromagnetic software. Then, the electromagnetic simulation of the magnetic field of the linear motor is performed under conditions of no load and full load. Next, the magnetic field of the motor is measured using a six-channel high-precision magnetic field test system, and the simulation and measurement results are compared. The result analysis indicates that the energy distribution of the electromagnetic field generated by the linear motor is uniform and that the magnetic induction intensity falls within the range of 0–1.1 T. Meanwhile, the linear motor can form a closed loop with a small electromagnetic field energy leakage. Combined with its installation structure, the radiation to the surrounding environment is weak, and the interference with the normal operation of the train control communication equipment is minimal. This study lays a foundation for analyzing electromagnetic distribution on the surface of the suspended permanent magnet maglev train. It also provides a basis for formulating various electromagnetic radiation protection measures and provides theoretical support for developing suspended permanent magnet maglev trains.
-
-
Investigation on the performance and flow characteristics of a liquid lead-bismuth pump
Yongchao Zhang,Can Kang,Yang Zhu,Hyoung Bum Kim 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.7
The liquid lead-bismuth pump is a core component of the main coolant circuit of the accelerator driven system. The pump performance has a significant effect on the safety and operational stability of the whole system. A liquid lead-bismuth pump was designed and the performance and flow characteristics of the pump were obtained numerically. Effects of transported medium on the performance of the pump and the forces acting on the hydraulic components were investigated. The results show that the operational performance of the pump is improved as the liquid medium of water is replaced with liquid lead-bismuth. The axial force acting on the impeller is dominated by the dynamic reverse force associated with flowing liquid lead-bismuth. Large-scale vortices formed at the bottom of the discharge chamber incur remarkable hydraulic loss. High risk of erosion exists at the outlet part of impeller blades and the inlet part of diffuser blades.
-
Yongchao Zhang,Minguan Yang,Dan Ni,Ning Zhang,Bo Gao 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.3
Understanding of turbulent flow in the reactor coolant pump (RCP) is a premise of the optimal design ofthe RCP. Flow structures in the RCP, in view of the specially devised spherical casing, are more complicatedthan those associated with conventional pumps. Hitherto, knowledge of the flow characteristics ofthe RCP has been far from sufficient. Research into the nonintrusive measurement of the internal flow ofthe RCP has rarely been reported. In the present study, flow measurement using particle imagevelocimetry is implemented to reveal flow features of the RCP model. Velocity and vorticity distributionsin the diffuser and spherical casing are obtained. The results illuminate the complexity of the flows in theRCP. Near the lower end of the discharge nozzle, three-dimensional swirling flows and flow separationare evident. In the diffuser, the imparity of the velocity profile with respect to different axial crosssections is verified, and the velocity increases gradually from the shroud to the hub. In the casing, velocitydistribution is nonuniform over the circumferential direction. Vortices shed consistently from thediffuser blade trailing edge. The experimental results lend sound support for the optimal design of theRCP and provide validation of relevant numerical algorithms.
-
Guan Yongchao,Zhang Meng,Wang Yingda,Liu Zhongzhuo,Zhao Zelin,Wang Hong,An Dingjie,Qian Aidong,Kang Yuanhuan,Sun Wuwen,Shan Xiaofeng 한국미생물학회 2022 The journal of microbiology Vol.60 No.12
Aeromonas veronii is a pathogen which can induce diseases in humans, animals and aquatic organisms, but its pathogenic mechanism and virulence factors are still elusive. In this study, we successfully constructed a mutant strain (ΔascP) by homologous recombination. The results showed that the deletion of the ascP gene significantly down-regulated the expression of associated effector proteins in A. veronii compared to its wild type. The adhesive and invasive abilities of ΔascP to EPC cells were 0.82-fold lower in contrast to the wild strain. The toxicity of ΔascP to cells was decreased by about 2.91-fold (1 h) and 1.74-fold (2 h). Furthermore, the LD50 of the mutant strain of crucian carp was reduced by 19.94-fold, and the virulence was considerably attenuated. In contrast to the wild strain, the ΔascP content in the liver and spleen was considerably lower. The titers of serum cytokines (IL-8, TNF-α, and IL-1β) in crucian carp after the infection of the ΔascP strain were considerably lower in contrast to the wild strain. Hence, the ascP gene is essential for the etiopathogenesis of A. veronii TH0426.
-
Ma, Yongchao,Lee, Jihoon,Liu, Yanliang,Hangoma, Pesi Mwitumwa,Park, Woon Ik,Lim, Jae-Hong,Jung, Yun Kyung,Jeong, Jung Hyun,Park, Sung Heum,Kim, Kwangho The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.20
<P>A cost-effective fabrication method that can produce a remarkable enhancement in the device efficiency along with a reduction in the fabrication cost is one of the crucial requirements for the commercialization of perovskite-based solar cells. Here, we report a low-cost, printable, and highly effective synchronized-pressing annealing (SPA) method for inverted planar perovskite solar cells. In this method, two films are combined face-to-face for annealing, and separated as in a roll-to-roll process. Consequently, the SPA method provides two homogeneous highly crystalline MAPbI3 films with monolithic millimeter-scale crystalline grains by intermediate-induced crystallization engineering. The grains present a tendency of oriented growth along the <110> direction, parallel to the substrate, which leads to efficient charge transport. The IPSCs fabricated by the SPA method demonstrate a high efficiency of ∼17% with significantly enhanced photocurrents and fill factors. Moreover, the characteristics of both top and bottom devices are very similar, with nearly identical <I>J</I>-<I>V</I> curves and photoresponse spectra. As the SPA method is compatible with the printing technology for mass production, and as it can produce twin devices of high quality <I>via</I> one fabrication process, it can provide a remarkable reduction in the fabrication cost.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
