A practical coherency model for spatially varying ground motions

Yang, Qing-Shan,Chen, Ying-Jun Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.9 No.2

Based on the discussion about some empirical coherency models resulted from earthquake-induced ground motion recordings at the SMART-1 array in Taiwan, and a heuristic model of the coherency function from elementary notions of stationary random process theory and a few simplifying assumptions regarding the propagation of seismic waves, a practical coherency model for spatially varying ground motions, which can be applied in aseismic analysis and design, is proposed, and the regressive coefficients are obtained using least-square fitting technique from the above recordings.

Study on the mechanical behaviors of timber frame with the simplified column foot joints

Qing-shan Yang,Jun-xiao He,Juan Wang 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.77 No.3

Column foot in traditional Chinese timber structures may be subjected to be uplifted due to the lateral load and subsequently reset under the vertical loads. The residual moment of the rocking column foot is the most important parameter representing the mechanical behaviors of column foot, and the simplification of joints is the basis of structural analysis of whole structure. The complicated mechanical behaviors of joint and the modeling of the column foot joint has been undertaken historically based on the experiments and numerical simulation. On the condition of limited application range of those models, a lack of simplified model to represent the mechanical behaviors of joint deserves attentions. There is a great need to undertake theoretical studies to derive the residual moment and make better simplified model of the joint. This paper proposes the residual moment and equivalent simplified model of the rotational stiffness for column foot joint. And, the timber frame is established based on the simplified model, which is verified by solid finite element model. Results show that a mutual agreement on the mechanical behaviors of the timber frame is obtained between the simplified model and the solid finite element model. This study can serve as the references of the structural analysis for the traditional timber structures.

Design and implementation of a SHM system for a heritage timber building

Qing-shan Yang,Juan Wang,Sunjoong Kim,Huihui Chen,Billie F. Spencer Jr 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.29 No.4

Heritage timber structures represent the history and culture of a nation. These structures have been inherited from previous generations; however, they inevitably exhibit deterioration over time, potentially leading to structural deficiencies. Structural Health Monitoring (SHM) offers the potential to assess operational anomalies, deterioration, and damage through processing and analysis of data collected from transducers and sensors mounted on the structure. This paper reports on the design and implementation of a long-term SHM system on the Feiyun Wooden Pavilion in China, a three-story timber building built more than 500 years ago. The principles and features of the design and implementation of SHM systems for heritage timber buildings are systematically discussed. In total, 104 sensors of 6 different types are deployed on the structure to monitor the environmental effects and structural responses, including air temperature and humidity, wind speed and direction, structural temperatures, strain, inclination, and acceleration. In addition, integrated data acquisition and transmission subsystem using a newly developed software platform are implemented. Selected preliminary statistical and correlation analysis using one year of monitoring data are presented to demonstrate the condition assessment capability of the system based on the monitoring data.

Estimation of extreme wind pressure coefficient in a zone by multivariate extreme value theory

Qing-shan Yang,Danyu Li,Yi Hui,Siu-Seong Law 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.3

Knowledge on the design value of extreme wind pressure coefficients (EWPC) of a specific zone of buildings is essential for the wind-resistant capacity of claddings. This paper presents a method to estimate the representative EWPC introducing the multivariate extreme value model. The spatial correlations of the extreme wind pressures at different locations can be consider through the multivariate extreme value. The moving average method is also adopted in this method, so that the measured point pressure can be converted to wind pressure of an area. The proposed method is applied to wind tunnel test results of a large flat roof building. Comparison with existing methods shows that it can give a good estimation for all target zones with different sizes.

Head-on Collision Between Two Envelope Solitary Waves in a Granular Medium

Wen-Qing Du,Jian-An Sun,Juan-Fang Han,Wen-Shan Duan,Yang-Yang Yang,Xin Jiang 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.75 No.11

We investigated the head-on collision between two envelope solitary waves. Head-on collisions between two envelope solitary waves are first discussed in one-dimension (1D) granular chains. The interesting result is that no phase shift or phase delay detected after the head-on collision between two envelope solitary waves. The maximum amplitude during the head-on collision between two envelope solitary waves is also found to be less than the sum of the amplitudes of the two envelope solitary waves, but is larger than the amplitude of the either of the envelope solitary waves.

Induction Chemotherapy Plus Concurrent Chemoradiotherapy versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma in Children and Adolescents: A Matched Cohort Analysis

Yang Li,Lin-Quan Tang,Li-Ting Liu,Shan-Shan Guo,Yu-Jing Liang,Xue-Song Sun,Qing-Nan Tang,Jin-Xin Bei,Jing Tan,Shuai Chen,Jun Ma,Chong Zhao,Qiu-Yan Chen,Hai-Qiang Mai 대한암학회 2018 Cancer Research and Treatment Vol.50 No.4

Purpose The purpose of this study was to evaluate the long-term clinical outcome and toxicity of induction chemotherapy (IC) followed by concomitant chemoradiotherapy (CCRT) compared with CCRT alone for the treatment of children and adolescent locoregionally advanced nasopharyngeal carcinoma (LACANPC). Materials and Methods A total of 194 locoregionally advanced nasopharyngeal carcinoma patients younger than 21 years who received CCRT with or without IC before were included in the study population. Overall survival (OS) rate, progression-free survival (PFS) rate, locoregional recurrence-free survival (LRFS) rate, and distant metastasis-free survival (DMFS) rate were assessed by the Kaplan-Meier method and a log-rank test. Treatment toxicities were clarified and compared between two groups. Results One hundred and thiry of 194 patients received IC+CCRT. Patients who were younger and with more advanced TNM stage were more likely to receive IC+CCRT and intensive modulated radiotherapy. The addition of IC before CCRT failed to improve survival significantly. The matched analysis identified 43 well-balanced patients in both two groups. With a median follow-up of 51.5 months, no differences were found between the IC+CCRT group and the CCRT group in 5-year OS (83.7% vs. 74.6%, p=0.153), PFS (79.2% vs. 73.4%, p=0.355), LRFS (97.7% vs. 88.2%, p=0.083), and DMFS (81.6% vs. 81.6%, p=0.860). N3 was an independent prognostic factor predicting poorer OS, PFS, and DMFS. The addition of IC was associated with increased rates of grade 3 to 4 neutropenia. Conclusion This study failed to demonstrate that adding IC before CCRT could provide a significant additional survival benefit for LACANPC patients. Further investigations are warranted.

Comparative Phylogenetic Relationships and Genetic Structure of the Caterpillar Fungus Ophiocordyceps sinensis and Its Host Insects Inferred from Multiple Gene Sequences

Qing-Mei Quan,Qing-Xia Wang,Xue-Li Zhou,Shan Li,Xiao-Ling Yang,Yun-Guo Zhu,Zhou Cheng 한국미생물학회 2014 The journal of microbiology Vol.52 No.2

Ophiocordyceps sinensis (Ascomycota: Ophiocordycipitaceae)is a native fungal parasite of Hepialidae caterpillars and oneof the most economically important medicinal caterpillarfungi in China. However, little is known about the phylogeneticand evolutionary relationships between O. sinensis andits host insects. In this study, nuclear ITS and β-tubulin sequencesfrom O. sinensis and mitochondrial COI, COII, andCytb sequences from its hosts were analyzed across 33 populationssampled from five regions in China. Phylogenetically,both O. sinensis and its hosts were divided into three geographicallycorrelated clades, and their phylogenies were congruent. Analysis of molecular variance and calculated coefficientsof genetic differentiation revealed significant geneticdivergence among the clades within both O. sinensis (FST=0.878, NST=0.842) and its hosts (FST=0.861, NST=0.816). Estimatedgene flow was very low for O. sinensis (Nm=0.04) andthe host insects (Nm=0.04) among these three clades. Manteltests demonstrated a significant correlation (P<0.01) betweenthe genetic distances for O. sinensis and its hosts, as well as asignificant association (P<0.05) between geographic and geneticdistances in both. The similar phylogenetic relationships,geographic distributions, and genetic structure and differentiationbetween O. sinensis and its hosts imply that they have coevolved.

Characteristics of Mammary Paget's Disease in China: a National-wide Multicenter Retrospective Study During 1999-2008

Zheng, Shan,Song, Qing-Kun,Zhao, Lin,Huang, Rong,Sun, Li,Li, Jing,Fan, Jin-Hu,Zhang, Bao-Ning,Yang, Hong-Jian,Xu, Feng,Zhang, Bin,Qiao, You-Lin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

The aim of this study was to detail characteristics of mammary Paget's disease (PD) representing the whole population in China. A total of 4211 female breast cancer inpatients at seven tertiary hospitals from seven representative geographical regions of China were collected randomly during 1999 to 2008. Data for demography, risk factors, diagnostic imaging test, physical examination and pathologic characters were surveyed and biomarker status was tested by immunohistochemistry. The differences of demography and risk factors between PD with breast cancer and other lesions were compared using Chi-square test or t-test, with attention to physical examination and pathological characters. The percentage of PD was 1.6% (68/4211) in all breast cancers. The mean age at diagnosis was 48.1, and 63.2% (43/68) patients were premenopausal. There is no difference in demography and risk factors between PD with breast cancer and other breast cancer (P > 0.05). The main pattern of PD in physical exam and pathologic pattern were patients presenting with a palpable mass in breast (65/68, 95.6%) and PD with underlying invasive cancer (82.4%, 56/68) respectively. The rate of multifocal disease was 7.4% (5/68). PD with invasive breast cancer showed larger tumor size, more multifocal disease, lower ER and PR expression and higher HER2 overexpression than those in other invasive breast cancer (P < 0.05). These results suggested that PD in China is a concomitant disease of breast cancer, and that PD with underlying invasive cancer has more multiple foci and more aggressive behavior compared with other breast invasive cancer. We address the urgent needs for establishing diagnostic and therapeutic guidelines for mammary PD in China.

miR-126 Suppresses the Proliferation of Cervical Cancer Cells and Alters Cell Sensitivity to the Chemotherapeutic Drug Bleomycin

Yu, Qing,Liu, Shan-Ling,Wang, He,Shi, Gang,Yang, Pei,Chen, Xin-Lian Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In cervical cancer, one of the most common malignant tumors in women worldwide, miR-126 has been reported to exhibit decreased expression. However, its role in cervical cancer cell proliferation and drug sensitivity has remained relatively unexplored. Here, we compared the expression of miR-126 in cervical cancer tissues (n = 20) with that in normal cervical tissue (n = 20) using quantitative RT-PCR. The viability of Siha cervical cancer cells was further measured by MTT assay after transfection with miR-126 mimic (Siha-miR-126 mimic) or microRNA mimic negative control (Siha-miR mimic NC) and after treatment with various concentrations of bleomycin (BLM). IC50s were calculated, and the survival rates (SRs) of Siha cells were calculated. miR-126 expression in cervical cancer tissue was significantly decreased compared with that in normal cervical tissue (P < 0.01). The relative SRs of Siha-miR-126 mimic cells were also significantly decreased compared with those of Siha-miR mimic NC cells at 24-96 h after transfection. The IC50 of BLM in Siha-miR-126 mimic cells ($50.3{\pm}2.02{\mu}g/mL$) was decreased compared with that in Siha-miR mimic NC cells ($70.5{\pm}4.33{\mu}g/mL$) at 48 h after transfection (P < 0.05). Finally, the SRs of Siha-miR-126 mimic cells were significantly lower than those of SihamiR mimic NC cells after cultured in medium containing 40 ${\mu}g/mL$ BLM for 24-96 h (P < 0.05). These results suggest that miR-126 is expressed at low levels in cervical cancer. Upregulation of miR-126 inhibited cervical cancer cell proliferation and enhanced the sensitivity to BLM. Thus, miR-126 may represent a novel approach to cervical cancer treatment.

Sensor selection approach for damage identification based on response sensitivity

Wang, Juan,Yang, Qing-Shan Techno-Press 2017 Structural monitoring and maintenance Vol.4 No.1

The response sensitivity method in time domain has been applied extensively for damage identification. In this paper, the relationship between the error of damage identification and the sensitivity matrix is investigated through perturbation analysis. An index is defined according to the perturbation amplify effect and an optimal sensor placement method is proposed based on the minimization of that index. A sequential sub-optimal algorithm is presented which results in consistently good location selection. Numerical simulations with a two-dimensional high truss structure are conducted to validate the proposed method. Results reveal that the damage identification using the optimal sensor placement determined by the proposed method can identify multiple damages of the structure more accurately.