Research on Mechanics of Longitudinal Joint in Shield Tunnel by the Nonlinear Spring Equivalent Method

Hao Jin,Shuo Yu,Shunhua Zhou,Junhua Xiao 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.2

Shield tunnel lining is mainly composed of prefabricated segment, accurate description of longitudinal seam joint mechanics is important for design and analysis of shield tunnel segmental linings, however, due to its stress state is complex and internal force changes show the characteristics of nonlinear, there is no more rapid and accurate calculation model to analysis the mechanics. In the view of the problem of the entity unit simulating bolt bending with low computing speed, the model of shield tunnel longitudinal seam that using the nonlinear spring to simulate bending bolt joint is proposed. Combined with longitudinal seam joint test, analysis the entity model and spring bolt model, the study concluded that: 1) the calculation results of spring bolt model are closer to the test results than entity unit model; and 2) calculation efficiency of spring bolt model bolt up 1 times than the physical model. Based on the spring bolt model, further study the relationship between viscous coefficient, friction coefficient and calculation efficiency, and analyzes the regularity of deformation and damage of shield tunnel connection.

V-life의 시각적 인지 반응이 팬 행동 의도에 미치는 영향에 관한 연구

Yin Shuo Han,Wang Jin Nan,Wang Cheng Hao 사단법인 한국융합기술연구학회 2023 아시아태평양융합연구교류논문지 Vol.9 No.4

This study focuses on the influence of V-life's visual cognitive response on fans' behavioral intention. Recently, a variety show called 2060, featuring an original virtual idol, caused a heated debate in China. The show gave these digital human the concept of " V-life(virtual life)". According to the results of the market survey, fans pay as much as 72.8% attention to the visual design of digital human. It can be inferred that the visual cognitive response of V-life will play an important role in the behavioral intention of fans. This study verified this influence path through a questionnaire survey and structural equation model analysis. The results show that, in the visual cognitive response of V-life, discomfort has a significant negative impact on verisimilitude and physical attractiveness. Following this, verisimilitude will have a positive impact on authenticity through social presence, while authenticity through social attractiveness will be positively influenced through physical attractiveness. Lastly, the authenticity of V-life will have a positive impact on the relationship maintenance intention, and will further have a positive impact on the product purchase intention through the relationship maintenance intention. Future research will continue to expand the findings to more fan groups and media types. 본 연구는 V-life의 시각적 인지 반응이 팬 행동 의도에 미치는 영향에 관한 연구이다. 본 연구는 주로 V-life의 시각적 인지 반응이 팬들의 행동 의도에 미치는 영향에 대해 탐구하고 있다. 이를 위해 최근 디지털 휴먼에게 V-life(가상 아이돌)라는 개념을 부여하는 데 지대한 역할을 한 '2060'이라는 예능 프로그램을 예시로써 소개하고 있다. 해당 프로그램은 예능에서 오리지널 디지털 휴먼을 처음 등장시켜 중국에서 뜨거운 논쟁과 신선한 바람을 가져왔다. 시장조사에 따르면 팬들의 관심 중 72.8%가 가상 아이돌의 외형 디자인에 집중되어 있음을 알 수 있다. 그렇기에 가상 아이돌인 V-life에 대한 시각적 인지 반응이 팬들의 행동 의도에 유의미한 영향을 미칠 것으로 가정할 수 있다. 본 연구는 설문조사 및 구조 방정식 모델의 분석 결과를 통해 해당 가설의 영향 경로를 확인했다. 연구 결과에 따르면 V-life의 시각적 인지 반응의 불편함(부조화)은 사실감과 신체적 매력에 부정적인 영향을 미치는 것을 알 수 있었으며 사실감은 사회적 실재감을 통해, 신체적 매력은 사회적 매력을 통해 진정성에 긍정적인 영향을 미치는 것으로 나타났다. 마지막으로 V-life의 진정성은 관계 유지 의도를 통해 제품 구매 의도에 더욱 긍정적인 영향을 미칠 수 있을 것으로 추정된다. 해당 연구 결과는 더 많은 팬 그룹 및 미디어 유형에 관한 후속 연구로 확대될 것으로 기대된다.

Expression and Clinical Significance of MicroRNA-376a in Colorectal Cancer

Mo, Zhan-Hao,Wu, Xiao-Dong,Li, Shuo,Fei, Bing-Yuan,Zhang, Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

The incidence of colorectal cancer (CRC) is increasing in many Asian countries and microRNAs have already been proven to be associated with tumorigenesis. Currently, microRNA-376a (miR-376a) expression and association with clinical factors in CRC remains unclear. In this study, real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was carried out on 53 matched pairs of CRC and adjacent normal mucosa to investigate the expression levels of miR-376a. According to the high or low expression of miR-376a, patients were divided into two groups. The relationship between miR-376a expression and clinicopathological factors of 53 patients was evaluated. Survival analysis of 53 CRC patients was performed with clinical follow-up information and survival curves were assessed by the Kaplan-Meier method. Immunohistochemistry (IHC) staining was performed on sections of paraffin-embedded tissue to investigate the vascular endothelial growth factor (VEGF) expression. MiR-376a showed low expression in cancer tissues compared to the adjacent normal tissues and altered high miR-376a expression tended to be positively correlated with advanced lymph node metastasis and shorter patient survival. VEGF IHC positivity was significantly more common in patients with high expression levels of miR-376a.Those results demonstrated that miR-376a may be a meaningful prognostic biomarker and potential therapeutic target in colorectal cancer.

Framework for Calculating the Vertical Human-Induced Vibration of the Suspension Footbridge Under the Random Pedestrian Flow

Yu Li,Dong-Shuo Yin,Jia-Hao Wang,Jia-Wu Li 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.5

Currently, the problem of human-induced vibration of suspension footbridges is a research hotspot in bridge engineering. Moreover, on the suspension footbridge deck, the walking parameters of pedestrians, the simulation of random pedestrian fl ow, and the calculation method of human-induced vibration are the keys to solving the above problem. Therefore, in this paper, the following three studies have been carried out: (1) Firstly, the Jiufengshan suspension footbridge was taken as the observation site, and the statistical values of the step frequency ( f ), step length ( l ), and walking velocity ( v ) of pedestrians on the suspension footbridge deck were investigated and obtained. (2) Secondly, by combining the “social force model” with the obtained f , l , and v , a Matlab program was compiled to simulate the random pedestrian fl ow on the suspension footbridge deck. (3) Finally, by combining the above program with the vertical vibration equations of the human–footbridge coupling system, a Matlab program was compiled to calculate the vertical human-induced vibration of the suspension footbridge deck, which then was used to study the infl uence of the random pedestrian fl ow and human–footbridge coupling eff ect on the vertical human-induced vibration of the suspension footbridge deck. So, the above studies can provide a meaningful reference for the design of suspension footbridges.

A High-Throughput Method Based on Microculture Technology for Screening of High-Yield Strains of Tylosin-Producing Streptomyces fradiae

Yao Zhiming,Fan Jingyan,Dai Jun,Yu Chen,Zeng Han,Li Qingzhi,Hu Wei,Yan Chaoyue,Hao Meilin,Li Haotian,Li Shuo,Liu Jie,Huang Qi,Li Lu,Zhou Rui 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.6

Tylosin is a potent veterinary macrolide antibiotic produced by the fermentation of Streptomyces fradiae; however, it is necessary to modify S. fradiae strains to improve tylosin production. In this study, we established a high-throughput, 24-well plate screening method for identifying S. fradiae strains that produce increased yields of tylosin. Additionally, we constructed mutant libraries of S. fradiae via ultraviolet (UV) irradiation and/or sodium nitrite mutagenesis. A primary screening of the libraries in 24-well plates and UV spectrophotometry identified S. fradiae mutants producing increased yields of tylosin. Mutants with tylosin yield 10% higher than the wild-type strain were inoculated into shake flasks, and the tylosin concentrations produced were determined by highperformance liquid chromatography (HPLC). Joint (UV irradiation and sodium nitrite) mutagenesis resulted in higher yields of mutants with enhanced tylosin production. Finally, 10 mutants showing higher tylosin yield were re-screened in shake flasks. The yield of tylosin A by strains UN-C183 (6767.64 ± 82.43 μg/ml) and UN-C137 (6889.72 ± 70.25 μg/ml) was significantly higher than that of the wild-type strain (6617.99 ± 22.67 μg/ml). These mutant strains will form the basis for further strain breeding in tylosin production.

Multiple damage detection of maglev rail joints using time-frequency spectrogram and convolutional neural network

Yi-Qing Ni,Su-Mei Wang,Gao-Feng Jiang,Yang Lu,Guobin Lin,Hong-Liang Pan,Junqi Xu,Shuo Hao 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.29 No.4

Maglev rail joints are vital components serving as connections between the adjacent F-type rail sections in maglev guideway. Damage to maglev rail joints such as bolt looseness may result in rough suspension gap fluctuation, failure of suspension control, and even sudden clash between the electromagnets and F-type rail. The condition monitoring of maglev rail joints is therefore highly desirable to maintain safe operation of maglev. In this connection, an online damage detection approach based on three-dimensional (3D) convolutional neural network (CNN) and time-frequency characterization is developed for simultaneous detection of multiple damage of maglev rail joints in this paper. The training and testing data used for condition evaluation of maglev rail joints consist of two months of acceleration recordings, which were acquired in-situ from different rail joints by an integrated online monitoring system during a maglev train running on a test line. Short-time Fourier transform (STFT) method is applied to transform the raw monitoring data into time-frequency spectrograms (TFS). Three CNN architectures, i.e., small-sized CNN (S-CNN), middle-sized CNN (M-CNN), and large-sized CNN (L-CNN), are configured for trial calculation and the M-CNN model with excellent prediction accuracy and high computational efficiency is finally optioned for multiple damage detection of maglev rail joints. Results show that the rail joints in three different conditions (bolt-loosenesscaused rail step, misalignment-caused lateral dislocation, and normal condition) are successfully identified by the proposed approach, even when using data collected from rail joints from which no data were used in the CNN training. The capability of the proposed method is further examined by using the data collected after the loosed bolts have been replaced. In addition, by comparison with the results of CNN using frequency spectrum and traditional neural network using TFS, the proposed TFSCNN framework is proven more accurate and robust for multiple damage detection of maglev rail joints.