Health monitoring sensor placement optimization for Canton Tower using virus monkey algorithm

Ting-Hua Yi,Hong-Nan Li,Xu-Dong Zhang 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.5

Placing sensors at appropriate locations is an important task in the design of an efficient structural health monitoring (SHM) system for a large-scale civil structure. In this paper, a hybrid optimization algorithm called virus monkey algorithm (VMA) based on the virus theory of evolution is proposed to seek the optimal placement of sensors. Firstly, the dual-structure coding method is adopted instead of binary coding method to code the solution. Then, the VMA is designed to incorporate two populations, a monkey population and a virus population, enabling the horizontal propagation between the monkey and virus individuals and the vertical inheritance of monkey’s position information from the previous to following position. Correspondingly, the monkey population in this paper is divided into the superior and inferior monkey populations, and the virus population is divided into the serious and slight virus populations. The serious virus is used to infect the inferior monkey to make it escape from the local optima, while the slight virus is adopted to infect the superior monkey to let it find a better result in the nearby area. This kind of novel virus infection operator enables the coevolution of monkey and virus populations. Finally, the effectiveness of the proposed VMA is demonstrated by designing the sensor network of the Canton Tower, the tallest TV Tower in China. Results show that innovations in the VMA proposed in this paper can improve the convergence of algorithm compared with the original monkey algorithm (MA).

Dynamic characteristics of multiple inerter based dampers for suppressing harmonically forced oscillations

Hua-ting Chen,Shaomin Jia,Xuefeng He 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.72 No.6

Based on the ball-screw mechanism, a tuned viscous mass damper (TVMD) has been proposed, which has functions of amplifying physical mass of the system and frequency tuning. Considering the sensitivity of a single TVMD’s effectiveness to frequency mistuning like that of the conventional tuned mass damper (TMD) and according to the concept of the conventional multiple tuned mass damper (MTMD), in the present paper, multiple tuned mass viscous dampers (MTVMD) consisting of many tuned mass dampers (TVMD) with a uniform distribution of natural frequencies are considered for attenuating undesirable vibration of a structure. The MTVMD is manufactured by keeping the stiffness and damping constant and varying the mass associated with the lead of the ball-screw type inerter element in the damper. The structure is represented by its mode-generalized system in a specific vibration mode controlled using the mode reduced-order method. Modal properties and fundamental characteristics of the MTVMD-structure system are investigated analytically with the parameters, i.e., the frequency band, the average damping ratio, the tuning frequency ratio, the total number of TVMD and the total mass ratio. It is found that there exists an optimum set of the parameters that makes the frequency response curve of the structure flattened with smaller amplitudes in a wider input frequency range. The effectiveness and robustness of the MTVMD are also discussed in comparison with those of the usual single TVMD (STVMD) and the results shows that the MTVMD is more effective and robust with the same level of total mass.

Stable and Recyclable SERS Substrates Based on Au-Loaded PET Nanocomposite Superhydrophobic Surfaces

Hua-Xiang Chen,Yu-Ting Wang,Ting-Ting You,Jin Zhai,Peng-Gang Yin 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.5

Novel surface-enhanced Raman scattering (SERS) substrates with stable and recyclable properties have been prepared by assembling gold nanoparticles-loaded PET (AuNPs/PET) nanocomposite superhydrophobic surfaces. After a physical vapor deposition process, the AuNPs/PET surfaces with vast plasmonic "hot spots" showed superhydrophobic properties, and it can hold target molecules droplets for rapid SERS detection. From blown off droplets and rinsed substrates with water after detection, we found that no probe molecules remained on the surfaces from Raman spectra. The prepared substrates were not contaminated in the detection process. Furthermore, the new SERS substrates were used for rapidly detecting droplets of crystal violet (CV) and the lowest detection concentration was about 1 x 10 -9 M. The as-prepared AuNPs/PET substrates also have good performance in terms of reproducibility and recyclability.

A new swarm intelligent optimization algorithm: Pigeon Colony Algorithm (PCA)

Ting-Hua Yi,Kai-Fang Wen,Hong-Nan Li 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.3

In this paper, a new Pigeon Colony Algorithm (PCA) based on the features of a pigeon colony flying is proposed for solving global numerical optimization problems. The algorithm mainly consists of the take-off process, flying process and homing process, in which the take-off process is employed to homogenize the initial values and look for the direction of the optimal solution; the flying process is designed to search for the local and global optimum and improve the global worst solution; and the homing process aims to avoid having the algorithm fall into a local optimum. The impact of parameters on the PCA solution quality is investigated in detail. There are low-dimensional functions, high-dimensional functions and systems of nonlinear equations that are used to test the global optimization ability of the PCA. Finally, comparative experiments between the PCA, standard genetic algorithm and particle swarm optimization were performed. The results showed that PCA has the best global convergence, smallest cycle indexes, and strongest stability when solving high-dimensional, multi-peak and complicated problems.

Sensor placement optimization in structural health monitoring using distributed monkey algorithm

Ting-Hua Yi,Hong-Nan Li,Xu-Dong Zhang 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.1

Proper placement of sensors plays a key role in construction and implementation of an effective structural health monitoring (SHM) system. This paper proposes a novel methodology called the distributed monkey algorithm (DMA) for the optimum design of SHM system sensor arrays. Different from the existing algorithms, the dual-structure coding method is adopted for the representation of design variables and the single large population is partitioned into subsets and each subpopulation searches the space in different directions separately, leading to quicker convergence and higher searching capability. After the personal areas of all subpopulations have been finished, the initial optimal solutions in every subpopulation are extracted and reordered into a new subpopulation, and the harmony search algorithm (HSA) is incorporated to find the final optimal solution. A computational case of a high-rise building has been implemented to demonstrate the effectiveness of the proposed method. Investigations have clearly suggested that the proposed DMA is simple in concept, few in parameters, easy in implementation, and could generate sensor configurations superior to other conventional algorithms both in terms of generating optimal solutions as well as faster convergence.

Optimal sensor placement for health monitoring of high-rise structure based on collaborative-climb monkey algorithm

Ting-Hua Yi,Hong-Nan Li,Xu-Dong Zhang,Guang-Dong Zhou 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.54 No.2

Optimal sensor placement (OSP) is an integral component in the design of an effectivestructural health monitoring (SHM) system. This paper describes the implementation of a novelcollaborative-climb monkey algorithm (CMA), which combines the artificial fish swarm algorithm (AFSA)with the monkey algorithm (MA), as a strategy for the optimal placement of a predefined number of sensors. Different from the original MA, the dual-structure coding method is adopted for the representation of designvariables. The collaborative-climb process that can make the full use of the monkeys’ experiences to guidethe movement is proposed and incorporated in the CMA to speed up the search efficiency of the algorithm. The effectiveness of the proposed algorithm is demonstrated by a numerical example with a high-risestructure. The results show that the proposed CMA algorithm can provide a robust design for sensornetworks, which exhibits superior convergence characteristics when compared to the original MA using thedual-structure coding method.

A new method for optimal selection of sensor location on a high-rise building using simplified finite element model

Ting-Hua Yi,Hong-Nan Li,Ming Gu 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.37 No.6

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it’s difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.

Ergostatrien-3β-ol (EK100) from Antrodia camphorata Attenuates Oxidative Stress, Inflammation, and Liver Injury In Vitro and In Vivo

Ting-Yu Chao,Cheng-Chu Hsieh,Shih-Min Hsu,Cho-Hua Wan,Guan-Ting Lian,Yi-Han Tseng,Yueh-Hsiung Kuo,Shu-Chen Hsieh 한국식품영양과학회 2021 Preventive Nutrition and Food Science Vol.26 No.1

Hepatic ischemia/reperfusion (IR) injury is a complication that occurs during liver surgery, whereby hepatic tissue is injured by oxygen deficiency during ischemia, then further damaged by a cascade of inflammatory and oxidative insults when blood is resupplied during reperfusion. Antrodia camphorata is an indigenous fungus in Taiwan and an esteemed Chinese herbal medicine with various bioactivities. This study examined the effect of ergostatrien-3β-ol (EK100), an active compound found in both the fruiting body and mycelia of A. camphorata, on IR injury pathologies in rats and cell models of oxidative and inflammatory stress. Male Sprague-Dawley rats were randomly assigned to receive a vehicle or 5 mg/kg EK100 prior to hepatic IR injury induced by 1 h ischemia followed by 24 h reperfusion, or a sham operation. RAW 264.7 murine macrophages and HepG2 hepatocytes were pretreated with EK100, then inflammation was induced with lipopolysaccharides in the former and oxidative stress was induced with hydrogen peroxide in the latter. EK100 decreased IR-induced elevation in serum levels of alanine aminotransferase and aspartate aminotransferase and lowered levels of the inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-6, and IL-1β. In addition, EK100 significantly reduced hepatic mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2, as well as nitrite production and iNOS gene expression in both hepatocyte and macrophage cell lines. We demonstrated that EK100 exhibits potent protection against hepatic IR injury, which may be used to design strategies to ameliorate liver damage during liver surgery.

Multi-stage structural damage diagnosis method based on “energy-damage” theory

Ting-Hua Yi,Hong-Nan Li,Hong-Min Sun 국제구조공학회 2013 Smart Structures and Systems, An International Jou Vol.12 No.3

Locating and assessing the severity of damage in large or complex structures is one of the most challenging problems in the field of civil engineering. Considering that the wavelet packet transform (WPT) has the ability to clearly reflect the damage characteristics of structural response signals and the artificial neural network (ANN) is capable of learning in an unsupervised manner and of forming new classes when the structural exhibits change, this paper investigates a multi-stage structural damage diagnosis method by using the WPT and ANN based on “energy-damage” theory, in which, the wavelet packet component energies are first extracted to be damage sensitive feature and then adopted as input into an improved back propagation (BP) neural network model for damage diagnosis in a step by step mode. To validate the efficacy of the presented approach of the damage diagnosis, the benchmark structure of the American Society of Civil Engineers (ASCE) is employed in the case study. The results of damage diagnosis indicate that the method herein is computationally efficient and is able to detect the existence of different damage patterns in the simulated experiment where minor, moderate and severe damages corresponds to involving in the loss of stiffness on braces or the removal bracing in various combinations.

Cable anomaly detection driven by spatiotemporal correlation dissimilarity measurements of bridge grouped cable forces

Ting-Hua Yi,Dong-Hui Yang,Hai-Lun Gu,Zhanjun Wu 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.30 No.6

Stayed cables are the key components for transmitting loads in cable-stayed bridges. Therefore, it is very important to evaluate the cable force condition to ensure bridge safety. An online condition assessment and anomaly localization method is proposed for cables based on the spatiotemporal correlation of grouped cable forces. First, an anomaly sensitive feature index is obtained based on the distribution characteristics of grouped cable forces. Second, an adaptive anomaly detection method based on the <i>k</i>-nearest neighbor rule is used to perform dissimilarity measurements on the extracted feature index, and such a method can effectively remove the interference of environment factors and vehicle loads on online condition assessment of the grouped cable forces. Furthermore, an online anomaly isolation and localization method for stay cables is established, and the complete decomposition contributions method is used to decompose the feature matrix of the grouped cable forces and build an anomaly isolation index. Finally, case studies were carried out to validate the proposed method using an in-service cable-stayed bridge equipped with a structural health monitoring system. The results show that the proposed approach is sensitive to the abnormal distribution of grouped cable forces and is robust to the influence of interference factors. In addition, the proposed approach can also localize the cables with abnormal cable forces online, which can be successfully applied to the field monitoring of cables for cable-stayed bridges.