http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Output Control of MIMO System with Unmatched Disturbance based on High-order Unknown Input Observer
Jiancheng Zhang,Fanglai Zhu 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.2
In this paper, the output control for a general MIMO linear system subjected to unmatched disturbance isconsidered. A smooth backstepping control law is developed under the assumption that the state and disturbance aswell as its derivatives are known firstly. Then in order to estimate the required information, a high-order unknowninput observer (HOUIO) is developed, and it is proven that based on the estimation by such the HOUIO, the designedcontroller can compensate all the disturbances from output channels and asymptotically drive the output to zero. Comparing with the traditional sliding mode control laws, the control law we design does not contain any switchingfunction, so it can effectively reduce the chattering. Finally, simulation results are given to show the effectivenessof our methods.
Jiancheng Liu,Yan Wei 대한수학회 2012 대한수학회보 Vol.49 No.2
In this paper, we investigate the hypersurface $M$ in a unit sphere with constant $k$-th mean curvature and two distinct principal curvatures,and characterize such a hypersurface.
A Novel Passivity-Based Resonant Instability Suppression Method for Grid-Connected VSC
Jiancheng Zhao,Kai Li,Xiaodong Wang,Chuan Xie,Hongbing Xu 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.1
The interaction between the three-phase voltage source converters (VSCs) and the power grid may cause high-frequency resonant instable problems. Studies have indicated that the non-passivity of VSCs is the main reason that leads to the resonances. The above-mentioned passive means that the equivalent output admittance of the VSC has a positive real part. In this paper, a novel damped Smith predictor is proposed to suppress the resonant instability problem that caused by time delay. The research proved that the proposed Smith predictor can signifi cantly improve the passivity of the VSC by reducing the width of the negative real part at the high-frequencies. Simulation and experimental results demonstrate that the proposed Smith predictor can distinctly improve the robustness of the VSC.
Jiancheng Tu,Shusheng Wang,Geping Wu,Yun Zuo,Lei Zhao 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.10
Alloferons are a group of naturally occurringpeptides primarily isolated from insects that are capable ofstimulating mouse and human NK cell cytotoxicity towardcancer cells. In this study, we found that a modified antibacterialpeptide had a broad range of action against bothgram-positive and gram-negative bacteria. A time-courseexperiment showed that CFU counts rapidly decreasedafter ZL-2 treatment, with the bacteria nearly eliminatedwithin 4 h. We also examined the synergy between thepeptide and antibiotics. The peptide ZL-2 resulted in asignificant synergistic improvement in the potencies ofampicillin, erythromycin and ceftazidime against methicillin-resistant bacteria. In addition, ZL-2 had no detectablecytotoxicity in mouse spleen cells or a mouse animalmodel. In the mouse model by i.p. inoculation with Escherichiacoli, timely treatment of i.p. injection with ZL-2resulted in 100-fold reduction in bacteria load in blood aswell as 80 % protection from death in the inoculated animals. In conclusion, we successfully identified a modifiedpeptide with maximal bactericidal activity. This study alsoprovides a potential therapeutic for the treatment of E. colisepticemia by increasing the activity of antimicrobials.
Jiancheng Liu,Hong Sun,Cunxi Nie,Wenxia Ge,Yongqiang Wang,Wen-Ju Zhang 한국식품과학회 2018 Food Science and Biotechnology Vol.27 No.6
In this study, the immunomodulatory activity of oligopeptide (CP) derived from solid-state fermented cottonseed meal were investigated in immunosuppressed BALB/c mice models by treatment with cyclophosphamide (CY). Results indicated that oligopeptide increased the thymus and spleen indices of CY-treated mice. The count of plague forming cells (PFC) and the content of half serum hemolysis (HC50) in immunosuppressive mice were restored to the normal level in CP-10 and CP-20 groups while the cytokines interleukin (IL)-2, IL-6, and tumor necrosis factor alpha (TNF-a) were increased significantly in CP-20 group. Similar increasing the immunoglobulin of IgG and IgM content in the serum of CP-10 group were also observed. These findings indicated that oligopeptide derived from solid-state fermented cottonseed meal had a strong immune-enhancing activity as well as a protective effect against immunosuppression induced by cyclophosphamide in mice.
The flow field in a centrifugal pump with a large tongue gap and back blades
Jiancheng Cai,Jie Pan,Andrew Guzzomi 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.11
In this paper, the unsteady 3-D turbulent flow fields in an end-suction centrifugal pump with a vaneless volute are studied numericallyat three different rotation speeds. The unshrouded impeller of the pump, as a reduced diameter version of the original full-size impeller,has five backswept blades and five pump-out blades. The results show that the flow rate and pressure vary with the rotational speed accordingto the similarity law, and the normalized internal flow fields at all speeds are very similar. Due to the reduced impeller diameter,the pump efficiency is relatively low. Flows discharged from the front and back blade passages interfere with each other and swirlingmotion exists in the volute. The pressure fluctuations on the casing wall near the impeller outlet are extracted, and their spectra show thatthe component at the blade passing frequency was prominent. This study sheds some light on the characteristics of the internal unsteadyflow of a centrifugal pump at different rotational speeds, and forms a basis for future study of flow induced pump vibration and noise.
Jiancheng Zhang,Jun Li,Fanglai Zhu,Xiaohang Li 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.6
This paper develops a new unknown input observer (UIO) design method for a class of discrete-timelinear descriptor systems when the observer matching condition is not satisfied. By equivalent transformations, thestate and unknown input observations of the descriptor system are changed to the UIO design problem for a generallinear dynamic system firstly. Then based on some further discussion on the concept of the system left invertibility,a new auxiliary output vector is constructed which allows us to remove the unknown inputs from the dynamicequation, and thereby a Luenberger-type observer can be constructed. One of the advantages of the present methodis that it can work only under the single strongly detectable condition. Finally, a simulation example is given toverify the effectiveness and show the superiorities of our methods.
HYPERSURFACES WITH CONSTANT k-TH MEAN CURVATURE AND TWO DISTINCT PRINCIPAL CURVATURES IN SPHERES
Liu, Jiancheng,Wei, Yan Korean Mathematical Society 2012 대한수학회보 Vol.49 No.2
In this paper, we investigate the hypersurface M in a unit sphere with constant k-th mean curvature and two distinct principal curvatures, and characterize such a hypersurface.