Modeling and Simulation of Active Half-vehicle Suspension Based on a New Output-feedback H∞ Controller

Chunyu Wei 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.3

The excellent performance of the controller and its insensitivity to time-delay are very important foractive suspension. In this paper, a novel output-feedback H∞ optimal controller is designed for half-vehicle suspension system and it performs better than the common output-feedback H∞ optimal controller. To further study theeffect of time-delay on the performance of the controller, a visual modeling and simulation method is proposed,and the detailed modeling process is given. The influence of time-delay on the vertical acceleration and pitchingacceleration of vehicle body is simulated under bump road excitation and C-class pavement excitation, respectively. The results show that when the time-delay is less than 25 ms, the performance of the controller is little affectedunder the bump road, and under the C-level road excitation, even if the time-delay reaches 50 ms, the performanceof the controller will not be affected.

Multiple Description Coding for H.264/AVC With Redundancy Allocation at Macro Block Level

Chunyu Lin,Tillo, Tammam,Yao Zhao,Byeungwoo Jeon IEEE 2011 IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDE Vol.21 No.5

<P>In this paper, a novel multiple description video coding scheme is proposed to insert and control the redundancy at macro block (MB) level. By analyzing the error propagation paths, the relative importance of each MB is determined. The paths, in practice, depend on both the video content and the adopted video coder. Considering the relative importance of the MB and the network status, an unequal protection for the video data can be realized to exploit the redundancy effectively. In addition, a simple and effective approach is introduced to tune the quantization parameter for the variable rate coding case. The whole scheme is implemented in H.264/AVC by employing its coding options, thus generating descriptions that are compatible with the baseline profile and extended profile of H.264/AVC. Due to its general property, the proposed approach can be employed for other hybrid video codecs. The results demonstrate the advantage of the proposed approach over other H.264/AVC multiple description schemes.</P>

A Distributed Approach of Proportional Bandwidth Allocation for Real-Time Services in UltraWideBand (UWB) WPANs

Chunyu Hu,Hwangnam Kim,Hou, J C,Chi, D,Ssai Shankar, N IEEE 2010 IEEE transactions on parallel and distributed syst Vol.21 No.11

<P>Quality of service (QoS) provisioning is one of the most important criteria in newly emerging UWB WPANs, as they are expected to support a wide variety of applications from time-constrained, multimedia streaming to throughput-hungry, content transfer applications. Recently, the WiMedia Alliance has announced the PHY/MAC specification together with the common radio platform for UWB WPANs. The WiMedia MAC uses the contention-free reservation-based access, which supports isochronous traffic with distributed reservation protocol (DRP), and the contention-based access, which provides service differentiation for best effort and variable-rate real-time traffic with prioritized channel access (PCA), similar to the enhanced distributed coordinated access (EDCA) in IEEE 802.11e. In this paper, we conduct a comprehensive theoretical analysis and show that with the currently recommended parameter setting, EDCA cannot provide adequate QoS. In particular, without responding to the system dynamics (e.g., taking account of the number of active stations in each class), EDCA cannot allocate bandwidth in a deterministic proportional manner and the system bandwidth is underutilized. After identifying the deficiency of EDCA, we propose an enhanced QoS-provisioning framework for the PCA scheme that dynamically controls channel access to adjust allocated bandwidth depending on the change of application's bit rate, i.e., variable-rate real-time traffic. We show that in this framework, 1) variable-rate real-time traffic is adaptively guaranteed of deterministic bandwidth via a contention-based reservation access method; 2) best effort traffic is provided with deterministic proportional QoS; and 3) moreover, the bandwidth utilization in PCA is maximized. By deterministic proportional QoS, we mean that the proposed protocol will maintain the ratio, r<SUB>j</SUB>, of per-station throughput attained by a station of class j to that attained by a station of class 1 at the targeted value, and yet, the real amount of network bandwidth is changing according to the current available network bandwidth. We have also validated and evaluated the QoS provisioning capability and practicality of the proposed PCA framework both via simulation and an empirical study with the Multiband Atheros Driver for WiFi (MADWifi) Linux driver for Wireless LAN devices with the Atheros chipset.</P>

Synthesis of Zirconium Oxides on silicon by Radio - Frequency Magnetron Sputtering Deposition

Chunyu Ma,Qingyu Zhang 한국진공학회(ASCT) 2003 Applied Science and Convergence Technology Vol.12 No.S1

Zirconium oxide films have been synthesized by radio-frequency magnetron sputtering deposition on n-Si(001) substrate with metal zirconium target at variant O₂ partial pressures. The influences of O₂ partial pressures of the morphology, deposition rate, microstructure, and the dielectric constant of ZrO₂ have been discussed. The results show that deposition rate of ZrO₂ films decreases, the roughness, and the thickness of the native SiO₂ interlayer increases with the increase of O₂ partial pressure. ZrO₂ films synthesized at low O₂ partial pressure are amorphous and monoclinic polycrystalline in nanometer scale at low O₂ partial pressure. The relative dielectrics of ZrO₂ films are in the range of 12 to 25.

Heliocoverpa armigera single nucleocapsid nucleopolyhedrovirus ORF52 is a ChaB homologous gene involved in per os infection

Chunyu Zhu,Fangliang Zheng,Sugai Yin,Hongsheng Liu,Yan Liu,Maosheng Zhang,Shuqin Xiong 한국유전학회 2014 Genes & Genomics Vol.36 No.6

The baculovirus ChaB proteins are conservedin all completely sequenced Lepidopteran NPVs and areannotated as putative DNA binding proteins. In our previousstudy, ORF51, a ChaB homologue from Helicoverpaarmigera single nucleocapsid nucleopolyhedrovirus(HearNPV) was found to be involved in budded virusproduction and DNA replication. In the present study, wecharacterized ORF52 (Ha52), the other ChaB homologousgene in HearNPV. 50-RACE revealed that Ha52 was transcribedfrom a conventional late promoter transcriptionalinitiator motif (TAAG) located 25 nucleotides upstream ofATG. Expression analysis demonstrated that HA52 proteinwas expressed from 48 to 96 h post infection. Western blotanalysis of virions from both budded viruses (BVs) andocclusion-derived viruses (ODVs) indicated that HA52 wasa structural component of nucleocapsid from ODV. Tostudy the function of Ha52 in the life cycle of HearNPV,Ha52-knockout and Ha52-restored viruses were generatedby the Bac-to-Bac system. Growth curve analyses showedthat the level of BV production in cells infected with Ha52null virus was similar to those infected with wild-typebacmid derived virus. However, bioassay showed thatdeletion of Ha52 significantly decreased the per os infectivityof HearNPV. Taken together, our results indicatedthat, unlike the previously characterized baculovirual ChaBgenes, Ha52 may be involved in HearNPV per os infection.

The Effect of Family Structure on Female Labor Participation – Empirical Analysis based on the 2011 China Health and Retirement Longitudinal Study

Chunyu Yang, Hongqiao Fu and Ling Li 한국사회복지학회 2016 Asian Social Work and Policy Review Vol.10 No.1

Using 2011 China Health and Retirement Longitudinal Study baseline data, this paper examines the effects of family structure on labor force participation. In consideration of the possible endogeneity provoked by family structure, we constructed regression models with instrument variables. Intergenerational co-residence significantly decreases women’s labor force participation by 14%, while it has no effect on men’s labor supply. One potential reason for this result is residential circumstance. As it is custom to live with elderly parents in multi-generation families in China, adult women often share the burden of all housework and are responsible for elderly care; thus, cohabiting with parents seems to have negative effects on female labor participation. On the contrary, Chinese culture dictates that men do not spend as much time as women on housework, thus, the probability of working in the labor market is not influenced by residential circumstance. If women were freed from housework responsibilities, the implication is that their participation in the labor force would increase

Oxidation Characteristics of TiC, TiN, CrN, TiCrN and TiAlN Coatings

Chunyu Xu,황연상,원성빈,이동복 한국표면공학회 2013 한국표면공학회 학술발표회 초록집 Vol.2013 No.5

Synchronization of two non-identical coupled exciters in a non-resonant vibrating system of plane motion

Chunyu Zhao,Qinghua Zhao,Yimin Zhang,Bangchun Wen 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.1

In the average method of modified small parameters, the synchronization of two coupled exciters is converted to a problem on the existence and stability of zero solutions for the average differential equations of small parameters over the average period of two exciters. To implement frequency capture, the torque of frequency capture should be greater than or equal to the absolute value of the difference between the residual electromagnetic torques of the two motors. Because each exciter is involved in the motion of the vibrating system it has excited, its relative moment of inertia is reduced. The reduction is proportional to half its coefficient of cosine effect of phase angles (CCEPA). Because one of the exciters is involved in the motion excited by the other, a coupled moment of inertia exists for the two exciters. The stability of the synchronization of the two exciters is affected by the reduction of their relative moments of inertia and their moment of coupling inertia. For the synchronization to be stable, two conditions must be satisfied: (1) the non-dimensional relative moments of inertia of the two exciters are all greater than zero, and (2) four times the product of their non-dimensional relative moments is greater than the square of the coefficient of coupled cosine effect (CCCPA). The stability of synchronization depends solely on the ratios of the masses of the two exciters to the mass of the vibrating system and the ratio of the distance between one exciter and the centroid of the rigid frame to the equivalent rotating radius of the vibrating system about its centroid of the rigid frame, and is independent of the parameters of the two induction motors.

Experimental study on through-beam connection system for concrete filled steel tube column-RC beam

Chunyu Tian,Congzhen Xiao,Tao Chen,Xueyi Fu 국제구조공학회 2014 Steel and Composite Structures, An International J Vol.16 No.2

A new through-beam connection system for a concrete filled steel tube column to RC beam is proposed. In this connection, there are openings on the steel tube while the reinforced concrete beams are continuous in the joint zone. The moment and shear force at the beam ends can be transferred to column by continuous rebar and concrete. The weakening of the axial load and shear bearing capacity due to the opening of the steel tube can be compensated by strengthening steel tube at joint zone. Using this connection, construction of the joint can be made more convenient since welding and hole drilling in situ can be avoided. Axial compression and reversed cyclic loading tests on specimens were carried out to evaluate performance of the new beam-column connection. Load-deflection performance, typical failure modes, stress and strain distributions, and the energy dissipation capacity were obtained. The experimental results showed that the new connection have good bearing capacity, superior ductility and energy dissipation capacity by effectively strengthen the steel tube at joint zone. According to the test and analysis results, some suggestions were proposed to design method of this new connection.

Functional Evaluation of Bovine Collagen and Cistanche Deserticola Compound Peptide

Chunyu Guo,Zhenni Zhang,Yan Zhang,Bo Yang,Xia Wue East Asian Health Association 2024 Journal of East Asian Bealth Vol.1 No.1

Purpose – Considering that elderly men’s health has common problems among the elderly. For example, most elderly chronic diseases are mostly related to inflammation, which can lead to malnutrition and osteoporosis. There are also gender differences such as hormone abnormalities and decreased male function. This article hopes to conduct a functional evaluation of a product that improves male nutrition and health care functions through animal experiments and in vitro cell experiments on bovine collagen and Cistanche deserticola compound peptides, verify its main functions, and improve the application of men’s health food in the elderly market. Design/Methodology/Approach – This article focuses on the design and investigation of the effect of this product on osteoporosis, male sperm motility and anti-inflammation. Therefore, the rat osteoporosis model, the cyclophosphamide testicular toxicity model, and the in vitro inflammatory cell experiment were used to produce corresponding experimental data. evaluate. Findings – Experiments have indeed verified that the compound peptide has the effects of preventing osteoporosis, promoting sperm motility, increasing testosterone levels and anti-inflammation. Research Implications – This study provides new ideas for the development of functional health foods for elderly men through the functional evaluation of complex peptides. It has certain significance for the selection of raw materials, formulation specifications and functional evaluation of men’s health products, and will also provide guidance for other scholars. Provide reference for subsequent research.