Modeling and performance evaluation of a piezoelectric energy harvester with segmented electrodes

Hongyan Wang,Lihua Tang,Xiaobiao Shan,Tao Xie,Yaowen Yang 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.14 No.2

Conventional cantilevered piezoelectric energy harvesters (PEHs) are usually fabricated with continuous electrode configuration (CEC), which suffers from the electrical cancellation at higher vibration modes. Though previous research pointed out that the segmented electrode configuration (SEC) can address this issue, a comprehensive evaluation of the PEH with SEC has yet been reported. With the consideration of delivering power to a common load, the AC outputs from all segmented electrode pairs should be rectified to DC outputs separately. In such case, theoretical formulation for power estimation becomes challenging. This paper proposes a method based on equivalent circuit model (ECM) and circuit simulation to evaluate the performance of the PEH with SEC. First, the parameters of the multi-mode ECM are identified from theoretical analysis. The ECM is then established in SPICE software and validated by the theoretical model and finite element method (FEM) with resistive loads. Subsequently, the optimal performances with SEC and CEC are compared considering the practical DC interface circuit. A comprehensive evaluation of the advantageous performance with SEC is provided for the first time. The results demonstrate the feasibility of using SEC as a simple and effective means to improve the performance of a cantilevered PEH at a higher mode.

Dust-ion Acoustic Shock Waves in a Dusty Multi-ion Plasma with Negatively Dust-charge Fluctuation

Hongyan Wang,Kaibiao Zhang 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.2

The nonlinear propagation of dust-ion acoustic shock waves in a collisionless, unmagnetizedmulti-ion dusty plasma contains Botlzemann-distributed electrons, negative and positive ions withextremely massive and stationary negative charge dust grains with dust charge fluctuations is investigated. By employing the reductive perturbation method, we obtain a Burgers equation thatdescribes the two-ion fluid dynamics. The dust charge variation is found to play an important rolein the formation of such dust-ion acoustic shock structures. The viscosity only affects the thicknessof the shock waves. The dependences of the shock wave’s velocity, height and thickness on thesystem parameters are investigated.

Research on Fractional Order Fuzzy PID Control of the Pneumatic-hydraulic Upper Limb Rehabilitation Training System Based on PSO

Hongyan Wang,Jinbo Lu 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.1

In this paper, a new type of pneumatic-hydraulic upper limb rehabilitation training system is designed, and the system modeling and control method are studied. The 2DOF fuzzy fractional PID controller is proposed, which provides a new reference for improving the control accuracy of two degrees of freedom pneumatic system. Due to the increase of the regulating parameters of the fractional order controller, a multi-objective particle swarm optimization algorithm is designed to determine the parameters of the control system and optimize the determination process of the parameters. In order to verify the effectiveness of the control method, an experimental study was carried out by building a pneumatic-hydraulic upper limb rehabilitation training system platform. Compared with PID controller, the overshoot of the system controlled by fractional order fuzzy PID controller is reduced by 17.3%. The peak time is shortened about 11.7%, and the delay time of sine tracking signal is reduced about 10.6%. The results show that the control performance of two degrees of freedom fractional order fuzzy PID controller is better than other controllers.

Modeling and performance evaluation of a piezoelectric energy harvester with segmented electrodes

Wang, Hongyan,Tang, Lihua,Shan, Xiaobiao,Xie, Tao,Yang, Yaowen Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.14 No.2

Conventional cantilevered piezoelectric energy harvesters (PEHs) are usually fabricated with continuous electrode configuration (CEC), which suffers from the electrical cancellation at higher vibration modes. Though previous research pointed out that the segmented electrode configuration (SEC) can address this issue, a comprehensive evaluation of the PEH with SEC has yet been reported. With the consideration of delivering power to a common load, the AC outputs from all segmented electrode pairs should be rectified to DC outputs separately. In such case, theoretical formulation for power estimation becomes challenging. This paper proposes a method based on equivalent circuit model (ECM) and circuit simulation to evaluate the performance of the PEH with SEC. First, the parameters of the multi-mode ECM are identified from theoretical analysis. The ECM is then established in SPICE software and validated by the theoretical model and finite element method (FEM) with resistive loads. Subsequently, the optimal performances with SEC and CEC are compared considering the practical DC interface circuit. A comprehensive evaluation of the advantageous performance with SEC is provided for the first time. The results demonstrate the feasibility of using SEC as a simple and effective means to improve the performance of a cantilevered PEH at a higher mode.

Research on facility layout optimization algorithm of deep-water semi-submersible drilling platform

Hongyan Wang,Wensheng Xiao,Lei Wu,Keke Wei,Congcong Xu,Chao Hou,Junguo Cui,Jie Li 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.2

We aimed to create a facility layout design of semi-submersible drilling platform (DSDP) with performance constraints. The Boltzmann survival mechanism of simulated annealing algorithm was introduced into the replacement strategy of genetic algorithm to form an improved genetic algorithm called genetic and simulated annealing algorithm (GASA). The new algorithm alleviates the “combination explosion” and premature convergence of the traditional genetic algorithm. The layout problem of DSDP is efficiently solved by using this new algorithm. When the number of layout objects increases, GASA’s performance is better than that of the genetic algorithm.

Finding Blue Tracks in Gephyrocharax melanocheir Fish Similar to the Locations of Acupuncture Meridians after Injecting Alcian Blue

Ze Wang,Wei-Bo Zhang,Shuyong Jia,Yu-Ying Tian,Guang-Jun Wang,Hongyan Lin 사단법인약침학회 2015 Journal of Acupuncture & Meridian Studies Vol.8 No.6

This study investigated whether a meridian-like distribution of Alcian blue (AB) existed after it was injected into a fish's body and suggested a new animal model for meridian study. Twenty Gephyrocharax melanocheir fish with translucent bodies were injected with AB at a point near the spinal column or the dorsal fin. Distribution of AB was observed using a digital camera and a stereomicroscope. Three or more obvious blue tracks were found: one along the spinal column, another along the posterior margin of the abdomen extending to the superior margin of the anal fin, and a third along both sides of the dorsal fin. They were similar to the locations of the governor, conceptual vessel, and urinary bladder meridians, respectively, on the human body according to the classic theory of traditional Chinese medicine. A few other blue tracks were also found, which apparently did not correspond to any known meridians. The results show that the tracks of AB share important similarities with the locations of classically described meridians and that they are mainly distributed in the interstitial space around bones and blood vessels and inside muscular interstices. This study may provide a new experimental animal model for exploring acupuncture meridians.

Overexpression of the Polygonum cuspidatum PcDREB2A Gene Encoding a DRE-Binding Transcription Factor Enhances the Drought Tolerance of Transgenic Arabidopsis thaliana

Hu Hongyan,Wang Xiaowei,Wu Zhijun,Chen Mo,Chai Tuanyao,Wang Hong 한국식물학회 2022 Journal of Plant Biology Vol.65 No.6

Plants have evolved complex signaling networks that enable them to adapt to adverse environmental conditions. The dehydration-responsive element-binding (DREB) transcription factors are important for plant responses to abiotic stresses. In this study, a new member of the AP2/ERF transcription factor gene family, PcDREB2A, was cloned and characterized from Polygonum cuspidatum, a traditional Chinese medicinal herb. PcDREB2A, which includes a typical AP2 domain, was clustered in the A-2 subgroup of the DREB subfamily. At the seedling stage, PcDREB2A expression was induced by cold, salt, and drought stresses. A yeast one-hybrid assay and an analysis of transiently transformed tobacco revealed that PcDREB2A can specifically bind to the DRE motif and transactivate reporter gene expression. Following 200 and 250 mM mannitol treatments, the PcDREB2A-overexpressing Arabidopsis thaliana lines had longer roots and a significantly higher fresh weight than the wild-type plants. Furthermore, under drought stress conditions, the PcDREB2A-overexpressing A. thaliana plants accumulated less malondialdehyde than the control plants. These results indicate that PcDREB2A encodes a novel DREB transcription factor in P. cuspidatum. Furthermore, the data generated in this study may be useful for researchers and breeders interested in genetically engineering plants to increase drought tolerance without inhibiting growth.

Neuroprotective potential of imatinib in global ischemiareperfusion- induced cerebral injury: possible role of Janus-activated kinase 2/signal transducer and activator of transcription 3 and connexin 43

Jieying Wang,Taomin Bai,Nana Wang,Hongyan Li,Xiangyang Guo 대한생리학회-대한약리학회 2020 The Korean Journal of Physiology & Pharmacology Vol.24 No.1

The present study was aimed to explore the neuroprotective role of imatinib in global ischemia-reperfusion-induced cerebral injury along with possible mechanisms. Global ischemia was induced in mice by bilateral carotid artery occlusion for 20 min, which was followed by reperfusion for 24 h by restoring the blood flow to the brain. The extent of cerebral injury was assessed after 24 h of global ischemia by measuring the locomotor activity (actophotometer test), motor coordination (inclined beam walking test), neurological severity score, learning and memory (object recognition test) and cerebral infarction (triphenyl tetrazolium chloride stain). Ischemia-reperfusion injury produced significant cerebral infarction, impaired the behavioral parameters and decreased the expression of connexin 43 and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in the brain. A single dose administration of imatinib (20 and 40 mg/kg) attenuated ischemia-reperfusioninduced behavioral deficits and the extent of cerebral infarction along with the restoration of connexin 43 and p-STAT3 levels. However, administration of AG490, a selective Janus-activated kinase 2 (JAK2)/STAT3 inhibitor, abolished the neuroprotective actions of imatinib and decreased the expression of connexin 43 and p-STAT3. It is concluded that imatinib has the potential of attenuating global ischemia-reperfusion- induced cerebral injury, which may be possibly attributed to activation of JAK2/ STAT3 signaling pathway along with the increase in the expression of connexin 43.

Thermal Management Performance of Epoxy Composites with Boron Nitride and Boron Phosphide Hybrid Fillers

Yi Wang,Kai Wang,Jiajun Hu,Kang Si,Hongyan Xia 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.6

Thermal interface materials with high thermal conductivity are the best choice to solve the current overheating problem of electronic devices, and the choice of thermal conductive fi ller is a key factor aff ecting the performance of thermal interface composites. Hexagonal boron nitride sheet is considered to be ideal thermal conductive fi ller, but the thermal conductive eff ect of single fi ller is still insuffi cient to meet actual needs. Here, a new type of hybrid fi ller mixed with boron nitride sheet and boron phosphide particles is used to prepare epoxy based composites. When the fi ller volume fraction is 40%, the thermal conductivity of composites reaches 3.18 W m −1 K −1 . Under the same content, the thermal conductivity of the composites with mixed fi llers outperforms those with boron nitride sheet alone. At the same time, the composite material shows high breakdown strength of 46 kV mm −1 . This work provides a new way to prepare thermal interface materials with high thermal conductivity for modern electronic packaging.

Helicobacter pylori-Induced Progranulin Promotes the Progression of the Gastric Epithelial Cell Cycle by Regulating CDK4

Ren Zongjiao,Li Jiayi,Du Xianhong,Shi Wenjing,Guan Fulai,Wang Xiaochen,Wang Linjing,Wang Hongyan 한국미생물·생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.7

Helicobacter pylori, a group 1 carcinogen, colonizes the stomach and affects the development of stomach diseases. Progranulin (PGRN) is an autocrine growth factor that regulates multiple cellular processes and plays a tumorigenic role in many tissues. Nevertheless, the mechanism of action of PGRN in gastric cancer caused by H. pylori infection remains unclear. Here, we investigated the role of PGRN in cell cycle progression and the cell proliferation induced by H. pylori infection. We found that the increased PGRN was positively associated with CDK4 expression in gastric cancer tissue. PGRN was upregulated by H. pylori infection, thereby promoting cell proliferation, and that enhanced level of proliferation was reduced by PGRN inhibitor. CDK4, a target gene of PGRN, is a cyclin-dependent kinase that binds to cyclin D to promote cell cycle progression, which was upregulated by H. pylori infection. We also showed that knockdown of CDK4 reduced the higher cell cycle progression caused by upregulated PGRN. Moreover, when the PI3K/Akt signaling pathway (which is promoted by PGRN) was blocked, the upregulation of CDK4 mediated by PGRN was reduced. These results reveal the potential mechanism by which PGRN plays a major role through CDK4 in the pathological mechanism of H. pylori infection.