ROTOR DYNAMIC MODEL AND UNBALANCED VIBRATIONS OF 1.5 ㎿ DOUBLY-FED WIND POWER GENERATOR

Guangfu Bin,Xuejun Li,Bobo Li,Jigang Wu 한국신재생에너지학회 2013 AFORE Vol.2013 No.-

Recent advances in near-infrared-II hollow nanoplatforms for photothermal-based cancer treatment

Li Zhang,Gerile Oudeng,Feiqiu Wen,Guangfu Liao 한국생체재료학회 2022 생체재료학회지 Vol.26 No.4

Near-infrared-II (NIR-II, 1000–1700 nm) light-triggered photothermal therapy (PTT) has been regarded as a promising candidate for cancer treatment, but PTT alone often fails to achieve satisfactory curative outcomes. Hollow nanoplatforms prove to be attractive in the biomedical field owing to the merits including good biocompatibility, intrinsic physical-chemical nature and unique hollow structures, etc. On one hand, hollow nanoplatforms themselves can be NIR-II photothermal agents (PTAs), the cavities of which are able to carry diverse therapeutic units to realize multi-modal therapies. On the other hand, NIR-II PTAs are capable of decorating on the surface to combine with the functions of components encapsulated inside the hollow nanoplatforms for synergistic cancer treatment. Notably, PTAs generally can serve as good photoacoustic imaging (PAI) contrast agents (CAs), which means such kind of hollow nanoplatforms are also expected to be multifunctional all-in-one nanotheranostics. In this review, the recent advances of NIR-II hollow nanoplatforms for single-modal PTT, dual-modal PTT/photodynamic therapy (PDT), PTT/chemotherapy, PTT/catalytic therapy and PTT/gas therapy as well as multi-modal PTT/chemodynamic therapy (CDT)/chemotherapy, PTT/chemo/gene therapy and PTT/PDT/CDT/starvation therapy (ST)/immunotherapy are summarized for the first time. Before these, the typical synthetic strategies for hollow structures are presented, and lastly, potential challenges and perspectives related to these novel paradigms for future research and clinical translation are discussed.

Layered Formation-containment Control of Multi-agent Systems in Constrained Space

Dongyu Li,Shuzhi Sam Ge,Guangfu Ma,Wei He 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.3

This paper addresses the layered formation-containment (LFC) problem for multiagents in the constrained space with a directed communication topology. The formation-containment problem is first defined using a layered framework, and a layered distributed finite-time estimator is proposed to acquire the target states for agents in each layer. Based on the proposed framework, the formation configuration and the mechanism of the information flow can be explored and designed naturally. To avoid collisions with borders, obstacles, as well as the other agents in the constrained space, an artificial potential function is designed based on the Dirac delta function. Further, a disturbance observer and adaptive neural networks (NNs) are applied to respectively tackle the external disturbance and the model uncertainties. The desired formation of each layer can be achieved while no collision occurs in the constrained space. The semi-global uniform ultimate boundedness of closed-loop errors is guaranteed by Lyapunov stability theory. Simulation results are given to show the effectiveness of the proposed approaches.

Family History and Stroke Risk in China: Evidence from a Large Cohort Study

Tian Tian,Guangfu Jin,Canqing Yu,Jun Lv,Yu Guo,Zheng Bian,Ling Yang,Yiping Chen,Hongbing Shen,Zhengming Chen,Zhibin Hu,Liming Li 대한뇌졸중학회 2017 Journal of stroke Vol.19 No.2

Background and Purpose Large cohort studies on relationship between family history of stroke(FHS) and stroke risk are lacking in Asians. We aimed to systematically evaluate the association ofFHS with stroke risk in a cohort study of 0.5 million Chinese adults. Methods Information about FHS was self-reported. The median follow-up time was 7.16 years andthe end-point of follow-up was incident stroke, which was entered directly into the China KadoorieBiobank system. Multivariate analyses were performed with Cox proportional hazards model, andinteraction analyses were carried using likelihood-ratio tests. Results Compared with participants without FHS, the hazard ratio (HR) (95% confidence interval,CI) of stroke for participants with FHS was 1.50 (1.46-1.55). The HRs increased with the number offirst degree relatives with stroke (HRs=1.41, 1.98 and 2.47 for 1, 2 and ≥3 relatives, respectively,Ptrend <0.001). The HRs were 1.57 (95% CI: 1.50-1.66) and 1.49 (95% CI: 1.45-1.54) for siblinghistory and parental history, respectively. Similar associations with offspring stroke risk wereobserved between paternal history (HR=1.48, 95% CI: 1.43-1.54) and maternal history (HR=1.49,95% CI: 1.43-1.55). Moreover, significant interactions were detected between FHS and health-riskbehaviors (tobacco smoking and alcohol drinking). Conclusions FHS is an independent risk factor for stroke in Chinese. The more first degree relativesare affected by stroke, the higher are individuals’ risk of suffering from stroke. The management ofthe health-risk behaviors for reducing stroke should be highlighted, especially for the individualswith FHS.

Manganese-based hollow nanoplatforms for MR imaging-guided cancer therapies

Shuang Liang,Guangfu Liao,Wenzhen Zhu,Li Zhang 한국생체재료학회 2022 생체재료학회지 Vol.26 No.3

Theranostic nanoplatforms integrating diagnostic and therapeutic functions have received considerable attention in the past decade. Among them, hollow manganese (Mn)-based nanoplatforms are superior since they combine the advantages of hollow structures and the intrinsic theranostic features of Mn2+. Specifically, the hollow cavity can encapsulate a variety of small-molecule drugs, such as chemotherapeutic agents, photosensitizers and photothermal agents, for chemotherapy, photodynamic therapy (PDT) and photothermal therapy (PTT), respectively. After degradation in the tumor microenvironment (TME), the released Mn2+ is able to act simultaneously as a magnetic resonance (MR) imaging contrast agent (CA) and as a Fenton-like agent for chemodynamic therapy (CDT). More importantly, synergistic treatment outcomes can be realized by reasonable and optimized design of the hollow nanosystems. This review summarizes various Mn-based hollow nanoplatforms, including hollow MnxOy, hollow matrix-supported MnxOy, hollow Mn-doped nanoparticles, hollow Mn complex-based nanoparticles, hollow Mn-cobalt (Co)-based nanoparticles, and hollow Mn-iron (Fe)-based nanoparticles, for MR imaging-guided cancer therapies. Finally, we discuss the potential obstacles and perspectives of these hollow Mn-based nanotheranostics for translational applications. Graphical AbstractMn-based hollow nanoplatforms such as hollow MnxOy nanoparticles, hollow matrix-supported MnxOy nanoparticles, Mn-doped hollow nanoparticles, Mn complex-based hollow nanoparticles, hollow Mn-Cobased nanoparticles and hollow Mn-Fe-based nanoparticles show great promise in cancer theranostics.

Preparation of b-Ca3(PO4)2 bioceramic powderfrom calcium carbonate and phosphoric acid q

Yun Zhang,Guangfu Yin,Shifu Zhu,Dali Zhou,Yuehua Wang,Yong Li,Lin Luo 한국물리학회 2005 Current Applied Physics Vol.5 No.5

When preparing b-tricalcium phosphate (b-TCP) with Ca(NO3)2 or Ca(OH)2 as the raw materials, because of the problem ofltering, it is dicult to industrialize traditional methods. In this paper,b-TCP was prepared with calcium carbonate and phospho-ric acid. According to XRD spectrum, the precursor of this system is octacalcium phosphate (OCP) [Ca8H2(PO4)6Æ5H2O] instead ofnon-stoichiometric hydroxyapatite (HA) obtained from traditional methods, and thermodynamics mechanism of the reaction wasalso studied. The crystalb-TCP powders were obtained after the precursor had been calcined at 8501150.C for 2 h. SEM imagesshowed that hardening could eliminate the reunion to a great extent, and obtain dispersiveb-TCP powders with a particle diameterbetween 0.5 and 2.0l m. The main advantages of this process over traditional methods are the fast reaction rate, the easy ltering,the ne particle size and the minimum impurity..

IMPROVED EMPIRICAL EIGENFUNCTIONS USED FOR MODELING OF FLEXIBLE WIND TURBINE BLADES BY BALANCING OF COVARIANCE MATRIX

Mian JIANG,Xuejun LI,Jigang WU,Guangfu BIN 한국신재생에너지학회 2013 AFORE Vol.2013 No.-

The Synthesis and Mechanism of (001)-Orientated Hematite Nano Rings: A Combined Theoretical and Experimental Investigation

Xiaonan Liu,Gang He,Jin-shan Li,Guangfu Yin 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.9

In this study, we synthesized Hematite nano rings using hydrothermal treatment. The experimental results demonstrated that the (001)-orientated Hematite nano rings were produced in all of the obtained products. To determine the formation mechanism of the (001) orientation, the lowest three index crystal faces of Hematite, Hematite (001), Hematite (101), and Hematite (104), were investigated with the Cambridge Sequential Total Energy Package (CASTEP) within the Materials Studio software environment (MS5.5) using the density functional theory (DFT). Our theoretical results showed that Hematite (001), the Hematite crystal with the lowest surface energy, had the greatest Hematite nano ring growth. In addition, we present the growth process of the Hematite nano rings based on our experimental and theoretical results.

Controlling Dynamic Formations of Mobile Agents Governed by Euler-Lagrange Dynamics

Liangming Chen,Qingkai Yang,Chuanjiang Li,Guangfu Ma 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.5

This paper studies the problem of controlling dynamic formations of mobile agents governed by EulerLagrange dynamics. Here a formation is said to be dynamic if as time evolves, the desired formation undergoes translation, scaling and rotation. First, a constant-gain formation control algorithm is designed such that all agents can converge to the desired dynamic formation, in which the graphic information is needed for the selection of constant gains. Then, another fully distributed formation control algorithm is further proposed by employing variablegain control techniques, which enables each agent to be independent of the knowledge of the overall interaction graph needed otherwise in the control gain. Instead of moving with a desired translational velocity, a centroidtracking formation control algorithm is also proposed such that the centroid of the formation tracks a desired trajectory. The parametric uncertainties are taken into consideration in the proposed formation control algorithms. Finally, simulation examples are provided to validate the effectiveness of the proposed control algorithms.

Dynamic analysis of the drive train of a wind turbine based upon the measured load spectrum

Caichao Zhu,Shuang Chen,Hua iju Liu,Huaqing Huang,Guangfu Li,Fei Ma 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.6

A dynamic model of the drive train of a megawatt wind turbine is proposed in which the blades, the hub, the main shaft, and the speedupgearbox are assumed as flexibilities. The external excitation due to the measured load spectrum and the internal excitations due to thetime-varying mesh stiffness, the transmission errors, and the meshing impacts within the gearbox are considered to predict the dynamicresponse of the system. Results show that the most vibration energy occurs at the speed-up gearbox, followed by the generator, and thenthe main shaft. An experimental remote real-time system is developed to monitor vibration performance of the drive train, with which theaccelerations of components are detected. The experimental results are in accordance with the theoretical results.