Structural health monitoring system for Sutong Cable-stayed Bridge

Hao Wang,Tianyou Tao,Aiqun Li,Yufeng Zhang 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.2

Structural Health Monitoring System (SHMS) works as an efficient platform for monitoring the health status and performance deterioration of engineering structures during long-term service periods. The objective of its installation is to provide reasonable suggestions for structural maintenance and management, and therefore ensure the structural safety based on the information extracted from the real-time measured data. In this paper, the SHMS implemented on a world-famous kilometer-level cable-stayed bridge, named as Sutong Cable-stayed Bridge (SCB), is introduced in detail. The composition and core functions of the SHMS on SCB are elaborately presented. The system consists of four main subsystems including sensory subsystem, data acquisition and transmission subsystem, data management and control subsystem and structural health evaluation subsystem. All of the four parts are decomposed to separately describe their own constitutions and connected to illustrate the systematic functions. Accordingly, the main techniques and strategies adopted in the SHMS establishment are presented and some extension researches based on structural health monitoring are discussed. The introduction of the SHMS on SCB is expected to provide references for the establishment of SHMSs on long-span bridges with similar features as well as the implementation of potential researches based on structural health monitoring.

Fuzzy Approximation-Based Backstepping Control of Permanent Magnet Synchronous Motor

Zhang Yufeng,Yan Qi,Huang Nan,Wu Zihui,Gong Hao,Du Guanghui 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

A permanent magnet synchronous motor(PMSM) control system based on backstepping control can effectively improve the dynamic performance, and the design process is simple and easy to be implemented in engineering. However, factors such as changes in motor parameters due to environmental changes, wear and aging, and external load disturbances can adversely affect the control system, resulting in degraded control performance. To address this problem, this paper proposes a fuzzy approximation-based backstepping control method for PMSM. The method constructs a mathematical model containing the perturbation term of the PMSM body parameters and the load disturbance term. And the universal approximation property of the fuzzy logic system is used to approximate the disturbance terms in the model, based on which a backstepping controller satisfying the stability requirements is designed. Finally, the simulation and experiment are given, which compare with the traditional backstepping method. The results show that the proposed method can effectively suppress the adverse effects of motor parameter changes and load disturbances on the motor control system.

Gastrointestinal microbiota alteration induced by Mucor circinelloides in a murine model

Katherine D. Mueller,Hao Zhang,Christian R. Serrano,R. Blake Billmyre,Eun Young Huh,Philipp Wiemann,Nancy P. Keller,Yufeng Wang,Joseph Heitman,Soo Chan Lee 한국미생물학회 2019 The journal of microbiology Vol.57 No.6

Mucor circinelloides is a pathogenic fungus and etiologic agent of mucormycosis. In 2013, cases of gastrointestinal illness after yogurt consumption were reported to the US FDA, and the producer found that its products were contaminated with Mucor. A previous study found that the Mucor strain isolated from an open contaminated yogurt exhibited virulence in a murine systemic infection model and showed that this strain is capable of surviving passage through the gastrointestinal tract of mice. In this study, we isolated another Mucor strain from an unopened yogurt that is closely related but distinct from the first Mucor strain and subsequently examined if Mucor alters the gut microbiota in a murine host model. DNA extracted from a ten-day course of stool samples was used to analyze the microbiota in the gastrointestinal tracts of mice exposed via ingestion of Mucor spores. The bacterial 16S rRNA gene and fungal ITS1 sequences obtained were used to identify taxa of each kingdom. Linear regressions revealed that there are changes in bacterial and fungal abundance in the gastrointestinal tracts of mice which ingested Mucor. Furthermore, we found an increased abundance of the bacterial genus Bacteroides and a decreased abundance of the bacteria Akkermansia muciniphila in the gastrointestinal tracts of exposed mice. Measurements of abundances show shifts in relative levels of multiple bacterial and fungal taxa between mouse groups. These findings suggest that exposure of the gastrointestinal tract to Mucor can alter the microbiota and, more importantly, illustrate an interaction between the intestinal mycobiota and bacteriota. In addition, Mucor was able to induce increased permeability in epithelial cell monolayers in vitro, which might be indicative of unstable intestinal barriers. Understanding how the gut microbiota is shaped is important to understand the basis of potential methods of treatment for gastrointestinal illness. How the gut microbiota changes in response to exposure, even by pathogens not considered to be causative agents of food-borne illness, may be important to how commercial food producers prevent and respond to contamination of products aimed at the public. This study provides evidence that the fungal microbiota, though understudied, may play an important role in diseases of the human gut.

An Octree-Based Two-Step Method of Surface Defects Detection for Remanufacture

Yan He,Wen Ma,Yufeng Li,Chuanpeng Hao,Yulin Wang,Yan Wang 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.2

Accurate and quick detection has a significant bearing on overall productivity of remanufacture. 3D scanning technologies have been widely applied in defects detection by comparing the damaged model with the nominal model. In this process, a huge amount of point cloud data is required to ensure detection accuracy whereas resulting in large storage space and long processing time of detection. This paper proposed an efficient two-step method based on octree to detect defects accurately and quickly for remanufacturing. In this method, the damaged point cloud and the nominal point cloud are first registered. Then a two-step detection approach is developed to extract the surface defects, coarse detection and detailed extraction, where the octree method is applied to create an effective topology of discrete points and perform the Boolean operation for defects extraction. In coarse detection, rough location and size information of the defects are acquired from the whole point cloud data. Based on coarse detected boundary box containing defects, the detailed extraction step is applied to extract corresponding defects shape accurately. The feasibility of proposed method was validated by using a case to detect defects of a damaged turbine blade and the detection results can be used to generate restoration tool path. The results show that the proposed method outperforms state-of-art defects detection methods, which can reduce time by 74.03% and reduce error by 36.86%, respectively.

Selective surface functionalization at regions of high local curvature in graphene

Wu, Qingzhi,Wu, Yaping,Hao, Yufeng,Geng, Jianxin,Charlton, Matthew,Chen, Shanshan,Ren, Yujie,Ji, Hengxing,Li, Huifeng,Boukhvalov, Danil W.,Piner, Richard D.,Bielawski, Christopher W.,Ruoff, Rodney S. The Royal Society of Chemistry 2013 Chemical communications Vol.49 No.7

<P>Monolayer graphene was deposited on a Si wafer substrate decorated with SiO<SUB>2</SUB> nanoparticles (NPs) and then exposed to aryl radicals that were generated <I>in situ</I> from their diazonium precursors. Using micro-Raman mapping, the aryl radicals were found to selectively react with the regions of graphene that covered the NPs. The enhanced chemical reactivity was attributed to the increased strain energy induced by the local mechanical deformation of the graphene.</P> <P>Graphic Abstract</P><P>Due to the increased strain energy caused by local mechanical deformation, aryl radicals were found to selectively react with regions of graphene that were curved by underlying SiO<SUB>2</SUB> nanoparticles. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cc36747e'> </P>

Oxygen-Promoted Chemical Vapor Deposition of Graphene on Copper: A Combined Modeling and Experimental Study

Srinivasan, Bharathi Madurai,Hao, Yufeng,Hariharaputran, Ramanarayan,Rywkin, Shanti,Hone, James C.,Colombo, Luigi,Ruoff, Rodney S.,Zhang, Yong-Wei American Chemical Society 2018 ACS NANO Vol.12 No.9

<P>Mass production of large, high-quality single-crystalline graphene is dependent on a complex coupling of factors including substrate material, temperature, pressure, gas flow, and the concentration of carbon and hydrogen species. Recent studies have shown that the oxidation of the substrate surface such as Cu before the introduction of the C precursor, methane, results in a significant increase in the growth rate of graphene while the number of nuclei on the surface of the Cu substrate decreases. We report on a phase-field model, where we include the effects of oxygen on the number of nuclei, the energetics at the growth front, and the graphene island morphology on Cu. Our calculations reproduce the experimental observations, thus validating the proposed model. Finally, and more importantly, we present growth rate from our model as a function of O concentration and precursor flux to guide the efficient growth of large single-crystal graphene of high quality</P> [FIG OMISSION]</BR>

Principal weighted support vector machines for sufficient dimension reduction in binary classification

Shin, Seung Jun,Wu, Yichao,Zhang, Hao Helen,Liu, Yufeng Oxford University Press 2017 Biometrika Vol.104 No.1

<P><B>SUMMARY</B></P><P>Sufficient dimension reduction is popular for reducing data dimensionality without stringent model assumptions. However, most existing methods may work poorly for binary classification. For example, sliced inverse regression (Li, 1991) can estimate at most one direction if the response is binary. In this paper we propose principal weighted support vector machines, a unified framework for linear and nonlinear sufficient dimension reduction in binary classification. Its asymptotic properties are studied, and an efficient computing algorithm is proposed. Numerical examples demonstrate its performance in binary classification.</P>

Removal and fate of carbamazepine in the microbial fuel cell coupled constructed wetland system

Jingyi Xie,Haixiao Li,Shiyu Wang,Hao Chen,Wei Jiang,Lin Zhang,Lianjie Wang,Yufeng Wu,Lirong Li,Xueqiang Lu 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

Carbamazepine (CBZ), which is difficult to remove in the wastewater treatment system and easily forms toxic transformation products during the treatment process, is one of the priority pollutants of pharmaceuticals and personal care products (PPCPs). Increasing attention has been paid to explore their treatment technology without side effects from the treatment products. This study aims to reveal the removal and transformation of CBZ in the microbial fuel cell coupled constructed wetland (CW-MFC) system. The CW-MFC system was operated continuously at room temperature for nearly 80 days. The results show that CW-MFC system can effectively remove CBZ with an average removal rate of 97%. Three transformation products were identified by liquid chromatography−high-resolution mass spectrometry: 2-(2-oxoquinazolin-1(2H)-yl) benzoic acid (TP267), methyl 2-(2-oxoquinazolin-1(2H)-yl) benzoate (TP281), 2-(2,4-dioxo-3,4-dihydroquinazolin-1(2H)-yl) benzoic acid (TP283). Except TP281 in the influent, the other transformation products were formed in the system, which indicated that TP267 and TP283 were the main transformation products of CBZ. The formation pathway of transformation products could be explained by reactions including oxidation, hydrolysis, bond rupture and intramolecular reaction. The results also indicate that the CW-MFC system might be a promising technology for PPCPs treatment.

OsSPL13 controls grain size in cultivated rice

Si, Lizhen,Chen, Jiaying,Huang, Xuehui,Gong, Hao,Luo, Jianghong,Hou, Qingqing,Zhou, Taoying,Lu, Tingting,Zhu, Jingjie,Shangguan, Yingying,Chen, Erwang,Gong, Chengxiang,Zhao, Qiang,Jing, Yufeng,Zhao, Y Nature Publishing Group, a division of Macmillan P 2016 Nature genetics Vol.48 No.4

<P>Although genetic diversity has a cardinal role in domestication, abundant natural allelic variations across the rice genome that cause agronomically important differences between diverse varieties have not been fully explored. Here we implement an approach integrating genome-wide association testing with functional analysis on grain size in a diverse rice population. We report that a major quantitative trait locus, GLW7, encoding the plant-specific transcription factor OsSPL13, positively regulates cell size in the grain hull, resulting in enhanced rice grain length and yield. We determine that a tandem-repeat sequence in the 5'UTR of OsSPL13 alters its expression by affecting transcription and translation and that high expression of OsSPL13 is associated with large grains in tropical japonica rice. Further analysis indicates that the large-grain allele of GLW7 in tropical japonica rice was introgressed from indica varieties under artificial selection. Our study demonstrates that new genes can be effectively identified on the basis of genome-wide association data.</P>

A 32.2 GHz Full Adder Designed with TLE Method in a InP DHBT Technology

Yi Zhang,Xiaopeng Li,Youtao Zhang,Yufeng Guo,Ying Zhang,Hao Gao 대한전자공학회 2021 Journal of semiconductor technology and science Vol.21 No.6

Ultra-high-speed full adder is the bottleneck in a tens of GHz Direct digital synthesizer (DDS). In this paper, a 32.2 GHz, 1bit full adder in a 0.7 μm InP double hetero-junction bipolar transistor (DHBT) technology is presented. In such a high-speed circuit, signal integrity is a crucial issue. Therefore, a transmission line equivalent (TLE) method is proposed. With the TLE method, the design of the full adder could be simplified with good accuracy. The synchronous latch is combined with adding operation to improve the calculation speed. A single-level parallel-gated circuit is designed using majority decision algorithm to reduce power consumption. Measurement results show that the maximum clock frequency of the full adder is 32.2-GHz, and the overall power consumption is 350 mW. The full adder is successfully adopted in a 17 GHz, 8 bit DDS which can synthesize sin-wave outputs from 66.41 MHz to 8.5 GHz in 66.41 MHz steps with an average Spurious-Free Dynamic Range (SFDR) of -18.1 dBc.