Analysis of three-dimensional thermal gradients for arch bridge girders using long-term monitoring data

Guang-Dong Zhou,Huan Zhang,Ting-Hua Yi,Bin Chen 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.2

Thermal loads, especially thermal gradients, have a considerable effect on the behaviors of large-scale bridges throughout their lifecycles. Bridge design specifications provide minimal guidance regarding thermal gradients for simple bridge girders and do not consider transversal thermal gradients in wide girder cross-sections. This paper investigates the three-dimensional thermal gradients of arch bridge girders by integrating long-term field monitoring data recorded by a structural health monitoring system, with emphasis on the vertical and transversal thermal gradients of wide concrete-steel composite girders. Based on field monitoring data for one year, the time-dependent characteristics of temperature and three-dimensional thermal gradients in girder cross-sections are explored. A statistical analysis of thermal gradients is conducted, and the probability density functions of transversal and vertical thermal gradients are estimated. The extreme thermal gradients are predicted with a specific return period by employing an extreme value analysis, and the profiles of the vertical thermal gradient are established for bridge design. The transversal and vertical thermal gradients are developed to help engineers understand the thermal behaviors of concrete-steel composite girders during their service periods.

Optimal sensor placement under uncertainties using a nondirective movement glowworm swarm optimization algorithm

Guang-Dong Zhou,Ting-Hua Yi,Huan Zhang,Huan Zhang,Hong-Nan Li 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.16 No.2

Optimal sensor placement (OSP) is a critical issue in construction and implementation of a sophisticated structural health monitoring (SHM) system. The uncertainties in the identified structural parameters based on the measured data may dramatically reduce the reliability of the condition evaluation results. In this paper, the information entropy, which provides an uncertainty metric for the identified structural parameters, is adopted as the performance measure for a sensor configuration, and the OSP problem is formulated as the multi-objective optimization problem of extracting the Pareto optimal sensor configurations that simultaneously minimize the appropriately defined information entropy indices. The nondirective movement glowworm swarm optimization (NMGSO) algorithm (based on the basic glowworm swarm optimization (GSO) algorithm) is proposed for identifying the effective Pareto optimal sensor configurations. The one-dimensional binary coding system is introduced to code the glowworms instead of the real vector coding method. The Hamming distance is employed to describe the divergence of different glowworms. The luciferin level of the glowworm is defined as a function of the rank value (RV) and the crowding distance (CD), which are deduced by non-dominated sorting. In addition, nondirective movement is developed to relocate the glowworms. A numerical simulation of a long-span suspension bridge is performed to demonstrate the effectiveness of the NMGSO algorithm. The results indicate that the NMGSO algorithm is capable of capturing the Pareto optimal sensor configurations with high accuracy and efficiency.

Analysis of three-dimensional thermal gradients for arch bridge girders using long-term monitoring data

Zhou, Guang-Dong,Yi, Ting-Hua,Chen, Bin,Zhang, Huan Techno-Press 2015 Smart Structures and Systems, An International Jou Vol.15 No.2

Thermal loads, especially thermal gradients, have a considerable effect on the behaviors of large-scale bridges throughout their lifecycles. Bridge design specifications provide minimal guidance regarding thermal gradients for simple bridge girders and do not consider transversal thermal gradients in wide girder cross-sections. This paper investigates the three-dimensional thermal gradients of arch bridge girders by integrating long-term field monitoring data recorded by a structural health monitoring system, with emphasis on the vertical and transversal thermal gradients of wide concrete-steel composite girders. Based on field monitoring data for one year, the time-dependent characteristics of temperature and three-dimensional thermal gradients in girder cross-sections are explored. A statistical analysis of thermal gradients is conducted, and the probability density functions of transversal and vertical thermal gradients are estimated. The extreme thermal gradients are predicted with a specific return period by employing an extreme value analysis, and the profiles of the vertical thermal gradient are established for bridge design. The transversal and vertical thermal gradients are developed to help engineers understand the thermal behaviors of concrete-steel composite girders during their service periods.

The potential molecular effects of bursal septpeptide II on immune induction and antitumor activity

Guang Fang Zhou,Qing Tao Liu,Bin Zhou,Ya Feng Qiu,Xiao Dong Liu,Zhi Yong Ma,Xiu Li Feng,Rui Bing Cao,Pu Yan Chen 대한수의학회 2015 Journal of Veterinary Science Vol.16 No.3

The bursa of Fabricius (BF) is the acknowledged central humoral immune organ in birds. Bursal septpeptide II (BSP-II) is animmunomodulatory bioactive peptide isolated from BF. To understand the effects of BSP-II on immune induction, gene expression profilesof hybridoma cells treated with BSP-II were evaluated. Pathway analysis showed that regulated genes were involved in cytokine-cytokinereceptor interactions, T cell receptor signaling pathway, and pathway in cancer. It was observed that BSP-II reduced tumor cells proliferationand stimulated p53 expression. These results indicate potential mechanisms underlying the effects of the humoral immune system on immuneinduction, including antitumor activities. Our study has provided a novel insight into immunotherapeutic strategies for treating human tumors.

Simultaneous treatment with sorafenib and glucose restriction inhibits hepatocellular carcinoma in vitro and in vivo by impairing SIAH1-mediated mitophagy

Zhou Jing,Feng Ji,Wu Yong,Dai Hui-Qi,Zhu Guang-Zhi,Chen Pan-Hong,Wang Li-Ming,Lu Guang,Liao Xi-Wen,Lu Pei-Zhi,Su Wen-Jing,Hooi Shing Chuan,Ye Xin-Pin,Shen Han-Ming,Peng Tao,Lu Guo-Dong 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Transarterial chemoembolization (TACE) is the first-line treatment for unresectable intermediate-stage hepatocellular carcinoma (HCC). It is of high clinical significance to explore the synergistic effect of TACE with antiangiogenic inhibitors and the molecular mechanisms involved. This study determined that glucose, but not other analyzed nutrients, offered significant protection against cell death induced by sorafenib, as indicated by glucose deprivation sensitizing cells to sorafenib-induced cell death. Next, this synergistic effect was found to be specific to sorafenib, not to lenvatinib or the chemotherapeutic drugs cisplatin and doxorubicin. Mechanistically, sorafenib-induced mitophagy, as indicated by PINK1 accumulation, increased the phospho-poly-ubiquitination modification, accelerated mitochondrial membrane protein and mitochondrial DNA degradation, and increased the amount of mitochondrion-localized mKeima-Red engulfed by lysosomes. Among several E3 ubiquitin ligases tested, SIAH1 was found to be essential for inducing mitophagy; that is, SIAH1 silencing markedly repressed mitophagy and sensitized cells to sorafenib-induced death. Notably, the combined treatment of glucose restriction and sorafenib abolished ATP generation and mitophagy, which led to a high cell death rate. Oligomycin and antimycin, inhibitors of electron transport chain complexes, mimicked the synergistic effect of sorafenib with glucose restriction to promote cell death mediated via mitophagy inhibition. Finally, inhibition of the glucose transporter by canagliflozin (a clinically available drug used for type-II diabetes) effectively synergized with sorafenib to induce HCC cell death in vitro and to inhibit xenograft tumor growth in vivo. This study demonstrates that simultaneous treatment with sorafenib and glucose restriction is an effective approach to treat HCC, suggesting a promising combination strategy such as transarterial sorafenib-embolization (TASE) for the treatment of unresectable HCC.

Field Circuit Coupling Optimization Design of the Main Electromagnetic Parameters of Permanent Magnet Synchronous Motor

Zhou, Guang-Xu,Tang, Ren-Yuan,Lee, Dong-Hee,Ahn, Jin-Woo The Korean Institute of Electrical Engineers 2008 Journal of Electrical Engineering & Technology Vol.3 No.1

The electromagnetic parameters of a permanent magnet synchronous motor (PMSM) such as the open load permanent magnet flux, d axis reactance $X_d$, and q axis reactance $X_q$, are most essential to the performance analysis and optimization design of the motor. Based on the numerical analysis of the 3D electromagnetic field, the three electromagnetic parameters of permanent magnet synchronous motors with U form interior rotor structures are calculated by FEA. The rules of the leakage coefficient and reactance parameters changing with the air gap length, permanent magnet magnetism length, and isolation magnetic bridge dimensions in the rotor are given. The calculated values agree well with the measured values. The FEA results are integrated with the self compiled electromagnetic design program to optimize the prototype motor. The tested performances of the prototype motor prove that the method is suitable for the optimization of motor structure.

Fifth Generation Communication Performance of Poly(ether ketone ketone)/Modified Montmorillonite Substrate

Guang Kui Zhou,Xiao Dong Zhi,Deng Ming Pan,Tim Hsu,Jen-taut Yeh 한국고분자학회 2022 Macromolecular Research Vol.30 No.2

Quaternary ammonium salt modified montmorillonite (QASMMT) nanoplatelets were well dispersed in poly(ether ketone ketone) (PEKK) polymers to make pleasing fifth generation (5G) substrates. Substantially smaller dielectric properties and linear thermal expansion coefficient (LCTE) were found for each PEKKa xQASMMTy film series filled with small and appropriate QASMMT loadings. The dielectric constant (εr) and dielectric loss (tan δ) values acquired for each PEKKa xQASMMTy film series reduced to a lowest value as QASMMT loadings approached 3wt%. Satisfactory εr (2.59, 2.71, and 2.80 at 1 MHz), tan δ (0.0032, 0.0038, and 0.0042 at 1 MHz) and LCTE (~36.8×10-6/℃, 38.8×10-6/℃ and 40.5×10-6/℃) for 5G communication were acquired for PEKKa 97QASMMT3 films filled with only 3wt% optimum loading of QASMMT nano-platelets. In the meantime, the onset degradation temperatures acquired for each PEKKa xQASMMTy film series increased substantially with increasing QASMMT loadings. All free volume properties, such as, the radius of the free-volume-cavity or free-volume-cavity numbers per unit volume evaluated for every PEKKa xQASMMTy film sequence enlarged to a largest value, as QASMMT loadings approached an appropriate value of 3wt%. Substantial smaller εr and tan δ were acquired for PEKKa and PEKKa xQASMMTy with larger free volume properties. Possible reasons accounting for these substantially diminished dielectric and LCTE properties of PEKKa xQASMMTy films are proposed.

A Fuzzy Logical Optimal Efficiency Control of Permanent Magnet Synchronous Motor

Guang Xu Zhou(주광성),Dong-Hee Lee(이동희),Jin-Woo Ahm(안진우) 대한전기학회 2007 대한전기학회 학술대회 논문집 Vol.2007 No.4

This paper presents a fuzzy logical control method to implement an on-line optimum efficiency control for Permanent Magnet Synchronous Motor. This method real-timely adjusts the output voltage of the inverter system to achieve the optimum running efficiency of the whole system. At first, the input power is calculated during the steady state in the process of efficiency optimizing. To exactly estimate the steady state of the system, this section needs check up the speed setting on timely. The second section is to calculate input power of de-bus. The exact measurement of the voltage and current is the vital point to acquire the input power. The third section is the fuzzy logic control unit, which is the key of the whole drive system. Based on the change of input power of de-bus and output voltage, the variable of output voltage is gained by the fuzzy logical unit. With the on-line optimizing, the whole system can fulfill the minimum input power of do-bus on the running state. The experimental result proves that the system applied the adjustable V/f control method and the efficiency-optimizing unit possesses optimum efficiency, and it is a better choice for simple variable speed applications such as fans and pump.

Field Circuit Coupling Optimization Design of the Main Electromagnetic Parameters of Permanent Magnet Synchronous Motor

Guang-Xu Zhou,Ren-Yuan Tang,Dong-Hee Lee,Jin-Woo Ahn 대한전기학회 2008 Journal of Electrical Engineering & Technology Vol.3 No.1

The electromagnetic parameters of a permanent magnet synchronous motor (PMSM) such as the open load permanent magnet flux, d axis reactance Xd, and q axis reactance Xq, are most essential to the performance analysis and optimization design of the motor. Based on the numerical analysis of the 3D electromagnetic field, the three electromagnetic parameters of permanent magnet synchronous motors with U form interior rotor structures are calculated by FEA. The rules of the leakage coefficient and reactance parameters changing with the air gap length, permanent magnet magnetism length, and isolation magnetic bridge dimensions in the rotor are given. The calculated values agree well with the measured values. The FEA results are integrated with the self compiled electromagnetic design program to optimize the prototype motor. The tested performances of the prototype motor prove that the method is suitable for the optimization of motor structure.

Study on Efficiency Optimizing of PMSM for Pump Applications

Guang-xu Zhou,Hui-jun Wang,Dong-Hee Lee,Jin-Woo Ahn 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-

In view of the operation characteristics of pump application, pump system should have high efficiency and energy saving during the whole operating process. A novel efficiency-optimization control strategy is presented to meet the demand of high efficiency of variable speed high efficiency PMSM. The core of this strategy is the excellent integration of mended maximum torque to current control algorithm, which is based on the losses model during the dynamic and the grade search method with changed step by fuzzy logic during the steady. A TMS320LF2407A DSP-based digital control inverter for variable speed high efficiency PMSM is developed. The performance experiments for control system of variable speed high efficiency PMSM have been completed. The tested result verified that the system can reliably operate with the different control strategy during the dynamic and steady operation, and the system has more perfect performances using the efficiency-optimization control.