A diagnostic approach for concrete dam deformation monitoring

Hao Gu,Zihan Jiang,Meng Yang,Li Shi,Xi Lu,Wenhan Cao,Kun Zhou,Lei Tang 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.6

In order to fully reflect variation characteristics of composite concrete dam health state, the monitoring data is applied to diagnose composite concrete dam health state. Composite concrete dam lesion development to wreckage is a precursor, and its health status can be judged. The monitoring data are generally non-linear and unsteady time series, which contain chaotic information that cannot be characterized. Thus, it could generate huge influence for the construction of monitoring models and the formulation of corresponding health diagnostic indicators. This multi-scale diagnosis process is from point to whole. Chaotic characteristics are often contained in the monitoring data. If chaotic characteristics could be extracted for reflecting concrete dam health state and the corresponding diagnostic indicators will be formulated, the theory and method of diagnosing concrete dam health state can be huge improved. Therefore, the chaotic characteristics of monitoring data are considered. And, the extracting method of the chaotic components is studied from monitoring data based on fuzzy dynamic cross-correlation factor method. Finally, a method is proposed for formulating composite concrete dam health state indicators. This method can effectively distinguish chaotic systems from deterministic systems and reflect the health state of concrete dam in service.

An analytical approach of behavior change for concrete dam by panel data model

Hao Gu,Meng Yang,Chongshi Gu,Wenhan Cao,Xiaofei Huang,Huaizhi Su 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.36 No.5

The behavior variation of concrete dam is investigated, based on a new method for analyzing the data model of concrete dam in service process for the limitation of wavelet transform for solving concrete dam service process model. The study takes into account the time and position of behavior change during the process of concrete dam service. There is no dependence on the effect quantity for overcoming the shortcomings of the traditional identification method. The panel data model is firstly proposed for analyzing the behavior change of composite concrete dam. The change-point theory is used to identify whether the behavior of concrete dams changes during service. The phase space reconstruction technique is used to reconstruct the phase plane of the trend effect component. The time dimension method is used to solve the construction of multi-transformation model of composite panel data. An existing 76.3-m-high dam is used to investigate some key issues on the behavior change. Emphasis is placed on conversion time and location for three time periods consistent with the practical analysis report for evaluating the validity of the analysis method of the behavior variation of concrete dams presented in this paper.

Sex Differences in Early and Late Recurrence after Liver Resection of Hepatocellular Carcinoma (A Multicenter Study from China)

( Jiong-jie Yu ),( Ju-dong Li ),( Xin-fei Xu ),( Zhen-li Li ),( Jun Han ),( Hao Xing ),( Han Wu ),( Jian-hong Zhong ),( Yi-sheng Huang ),( Ya- Hao Zhou ),( Ting-hao Chen ),( Hong Wang ),( Wei-min Gu ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: There is a striking sex difference in the incidence of hepatocellular carcinoma (HCC), with a strong predominance for males. However, the impact of sex on the incidence of recurrence after curative resection of HCC remains controversial. Herein, we assess sex differences in the risks of recurrence and mortality for patients undergone curative resection of HCC. Methods: Data from 1,435 HCC patients undergone curative resection (1,228 males and 207 females) between 2004 and 2014 at five institutions in China were retrospectively analyzed. Patients’ baseline characteristics, operative variables, and rates of early recurrence (≤ 2 years after resection), late recurrence (> 2 years) and cancer-specific mortality (CSM) were evaluated and compared. Multivariable competing-risks regression analyses were performed to identify predictors associated with CSM, early and late recurrence. Results: The early recurrence rates between males and females were similar (43.3% vs. 42.0%, P=0.728), but the late recurrence and CSM rates in males were higher when compared to females (17.2% vs. 11.2%, P=0.044; 42.8% vs. 34.3%, P=0.022). Multivariable competing-risks regression analyses revealed no sex difference in early recurrence; however, males had significantly higher late recurrence rate [hazard ratio (HR), 1.752; 95% CI, 1.145-2.682; P=0.010] and CSM rate (HR, 1.307; 95% CI, 1.015-1.683; P=0.038) than females. Conclusions: Males had significantly higher late recurrence and CSM rates after curative resection of HCC than females. This suggests postoperative surveillance for HCC recurrence be varied by sex, especially for patients without recurrence at 2 years after resection.

Study of Short-term Wind Power Prediction Considering the Individual Sample Prediction Error Correction

Gu Bo,Hu Hao,Liu Xinyu,Zhang Hongtao 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.3

Study on modulation of near infrared radiation based on plasma photonic crystal

Hao Jiong-Ju,Xie Xun,Gu Ke-Da,Liu Yu-Jie,Xia Lei,Yang Hong-Wei 한국물리학회 2020 Current Applied Physics Vol.20 No.8

In this paper, a plasma photonic crystal (PPC) for infrared radiation modulation which is composed of indium tin oxide (ITO) and plasma is proposed. The performance of plasma photonic crystal in near infrared radiation modulation is researched by transfer matrix method (TMM). The simulation results show that the near infrared radiation pass band can be adjusted by the changing of plasma frequency of plasma. The reflection to near infrared radiation by plasma photonic crystal increases with plasma frequency and that of absorption decreases. In addition, the modulation performance of the plasma photonic crystal at different incidence wave angles is also studied. The results show that the incident wave angles have little effect on the transmission of plasma photonic crystal in near infrared band. The reflection of the plasma photonic crystal to near infrared radiation decreases with increasing of the incident wave angle, but that of the absorption increases with the incident wave angle. Therefore, the proposed plasma photonic crystal has a potential application in tunable near infrared filter devices.

Moving Target Detection and Tracking in Complex Background

Gu Bo,Hu Hao,Ren Yan,Liu Xinyu 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.9

The influence of environment changing, e.g. background beam change, trees waggle, and rain or snow day brings More difficult for moving target detecting. A background dynamic generation algorithm is presented in the paper, and the background dynamic generation algorithm is used to dynamically construct background image, the impact of the environment change is reduced in a certain extent for the moving target detection. Secondly, the background difference method is used to detect the moving target, when the moving target exists, the direction and the coordinate of the moving target is determined according to the result of continuous 2 frame images subtract the background. Finally, an algorithm for calculating the rotation angle of the pan/tilt/zoom is presented, the horizontal rotation angle and the vertical rotation angle of the pan/tilt/zoom is calculated according to the pan/tilt/zoom rotation angle algorithm, and the moving target detection and automatic tracking function is realized.

Remote Localization of Network-based Automatic Guided Vehicles with a Novel Quantized Set-membership Approach

Hao Yang,Yilian Zhang,Wei Gu,Fuwen Yang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.8

This paper investigates the remote localization problem for a network-based automatic guided vehicle (AGV) system. Considering the constraints of network bandwidth and the interference of unknown-but-bounded (UBB) noises, a novel quantized set-membership approach is proposed. First, a differential zooming strategy is designed for the quantization process of the measurement signals in order to reduce the quantization error and the negative influence of the quantization effects. Then, a remote modified set-membership filter is designed to eliminate the influence of UBB noises and obtain the optimal position state estimation ellipsoid for the considered AGV. Sufficient conditions for the existence of the set-membership filter are derived and a recursive algorithm is provided for computing the ellipsoid that guarantees to contain the true state. Finally, the remote localization performance analysis verifies the effectiveness of the proposed quantized set-membership approach for the considered AGV.

Layout Optimization of Stiffeners in Heavy-Duty Thin-Plate Box Grider

Hao Zhang,Yixiao Qin,Jinpeng Gu,Haibiao Gao,Qianqian Jiao,Feng Wang,Zhenshan Guo,Yangyang Zhang,Chenghong Mi 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.8

The optimization of layout and sizes of the stiffeners in heavy-duty box girder could make this kind of the structure more compact and reasonable, which has certain engineering values. In this study, on the basis of the establishment of parametric finite element model, the function approaching method and gradient search method are combined to form a high-precision optimization algorithm, which makes structural analysis be integrated into the optimization process. The optimization takes the type and location of longitudinal stiffening ribs and the thickness and hole position of transverse diaphragms as design variables, the box girder structural behaviors as constraint conditions, and the total volume as objective function. Finally, the weight is reduced by nearly 7%. More importantly, the new asymmetrical layout of the stiffeners is obtained, the distance between the longitudinal stiffening ribs on the main web and the neutral layer is longer than the distance between the longitudinal stiffening ribs on the secondary web and the neutral layer, and the hole position of transverse diaphragms is close to the secondary web. Compared with the current production of symmetrical layout structure, this layout provides a new idea for the design of stiffeners in the bias-rail box girder.

Joint Phase Detection and Amplitude Detection for Spectrum Sensing

Hao Wei Li,Jun Rong Gu,Jae Moung Kim 한국통신학회 2010 한국통신학회 학술대회논문집 Vol.2010 No.6

Mechanical Properties and Microstructure of Basalt Fiber Reinforced Concrete Under the Single-Side Salt-Freezing–Drying–Wetting Cycles

Hao Zeng,Jin Zhang,Yang Li,Xin Su,CongZhi Gu,Kai Zhang 한국콘크리트학회 2022 International Journal of Concrete Structures and M Vol.16 No.6

In the past, the salt freezing test does not often accord with the actual service environment of engineering, thus, we designed a test method of single-side salt-freezing–drying–wetting cycles. The mechanical properties and microstructure of ordinary concrete and basalt fiber reinforced concrete were studied. The mechanical property test is aimed at the splitting tensile strength and compressive strength of concrete after different cycles. The microstructure test is to study the hydration products by scanning electron microscope (SEM) and the pore structure of concrete by mercury intrusion porosimetry (MIP) test. The results indicate that the addition of basalt fiber can improve the compactness and pore structure of concrete. It is beneficial to enhance the durability of concrete under single-side salt-freezing–drying–wetting cycles. The improving effect of basalt fiber is better on the splitting tensile strength of concrete than the compressive strength. Basalt fiber exerts the best effect on reducing harmful holes in concrete. However, there is an optimal range of basalt fiber content, the performance of concrete will deteriorate with excessive fiber content. The cycles will destroy the hydration products of concrete and the synergistic effect between hydration products and fibers, but has little effect on the three-dimensional network constructed by basalt fibers. The pore structure of concrete is correlated with the mechanical properties of it under cyclic conditions, which is worth further study.