Empirical formulas to estimate cable tension by cable fundamental frequency

Wei-Xin Ren,Gang Chen,Wei-Hua Hu 국제구조공학회 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.3

Empirical formulas to estimate cable tension by cable fundamental frequency

Ren, Wei-Xin,Chen, Gang,Hu, Wei-Hua Techno-Press 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.3

The cable tension plays an important role in the construction, assessment and long-term health monitoring of cable structures. The cable vibration equation is nonlinear if cable sag and bending stiffness are included. The engineering implementation of a vibration-based cable tension evaluation is mostly carried out by the simple taut string theory. However, the simple theory may cause unacceptable errors in many applications since the cable sag and bending stiffness are ignored. From the practical point of view, it is necessary to have empirical formulas if they are simple and yet accurate. Based on the solutions by means of energy method and fitting the exact solutions of cable vibration equations where the cable sag and bending stiffness are respectively taken into account, the empirical formulas are proposed in the paper to estimate cable tension based on the cable fundamental frequency only. The applicability of the proposed formulas is verified by comparing the results with those reported in the literatures and with the experimental results carried out on the stay cables in the laboratory. The proposed formulas are straightforward and they are convenient for practical engineers to fast estimate the cable tension by the cable fundamental frequency.

No Association Between Tea Consumption and Risk of Renal Cell Carcinoma: A Meta-analysis of Epidemiological Studies

Hu, Zheng-Hui,Lin, Yi-Wei,Xu, Xin,Chen, Hong,Mao, Ye-Qing,Wu, Jian,Xu, Xiang-Lai,Zhu, Yi,Li, Shi-Qi,Zheng, Xiang-Yi,Xie, Li-Ping Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Objective: To evaluate the association between tea consumption and the risk of renal cell carcinoma. Methods: We searched PubMed, Web of Science and Scopus between 1970 and November 2012. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Results: Twelve epidemiological studies (ten case-control studies and two cohort studies) were included in the final analysis. In a meta-analysis of all included studies, when compared with the lowest level of tea consumption, the overall relative risk (RR) of renal cell carcinoma for the highest level of tea consumption was 1.03 (95% confidence interval [CI] 0.89-1.21). In subgroup meta-analyses by study design, there was no significant association between tea consumption and renal cell carcinoma risk in ten case-control studies using adjusted data (RR=1.08, 95% CI 0.84-1.40). Furthermore, there was no significant association in two cohort studies using adjusted data (RR=0.95, 95% CI 0.81-1.12). Conclusion: Our findings do not support the conclusion that tea consumption is related to decreased risk of renal cell carcinoma. Further prospective cohort studies are required.

Performance and Applicability Analysis of Recognizing Microseismic Waveforms Using Neural Networks in Tunnel Engineering

Wei Zhang,Xin Bi,Lei Hu,Pengxiang Li,Zhibin Yao 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.2

The sudden and harmful nature of rockbursts in tunnels necessitates an accurate and applicable method for automatically recognizing rock fracture signals during rockburst microseismic (MS) monitoring. In this paper, the performance and applicability of recognizing MS waveforms using an artificial neural network (ANN) and a deep neural network (DNN) were studied in tunnels excavated by different methods. The results show that ANN performs very well in recognizing rock fracturing waveforms with a signal-to-noise ratio (SNR) ≥ 3 but has a low accuracy for those with an SNR < 3. The DNN also performs well for waveforms with SNR ≥3, and has a relatively high accuracy for waveforms with SNR < 3. The ANN model can be used in tunnels excavated by drilling and blasting (D&B) since there are fewer “small” rock fracturing events. The DNN model is applicable in tunnels excavated by the tunnel boring machine (TBM), recognizing more “small” events. In addition, the ANN model is a better choice, with fewer training samples at the initial stage of monitoring working. With continuous monitoring, the DNN model can be used to ensure and improve the accuracy. These results lay a foundation for automatic rockburst MS monitoring techniques in tunnel engineering.

Genome-wide association study of gastric adenocarcinoma in Asia: a comparison of associations between cardia and non-cardia tumours

Hu, Nan,Wang, Zhaoming,Song, Xin,Wei, Lixuan,Kim, Byung Sik,Freedman, Neal D,Baek, Jiwon,Burdette, Laurie,Chang, Jiang,Chung, Charles,Dawsey, Sanford M,Ding, Ti,Gao, Yu-Tang,Giffen, Carol,Han, Yaling British Medical Association 2016 Gut Vol.65 No.10

<P>Objective Genome-wide association studies (GWAS) of gastric cancer have reported differences in single-nucleotide polymorphism (SNP) associations for tumour subtypes, particularly when divided by location into the gastric cardia versus the non-cardia. Design Here we present results for a GWAS using 2350 East Asian gastric cancer cases divided as 1189 gastric cardia and 1027 gastric non-cardia cases and 2708 controls. We also included up to 3042 cardia cases, 4359 non-cardia cases and 7548 controls for replication from two Chinese studies and one Korean study. From the GWAS, we selected 12 top SNPs for each gastric cancer subtype, 4 top SNPs for total gastric cancer and 1 SNP in MUC1 for replication testing. Results We observed genome-wide significant associations for rs10074991 in PRKAA1 at 5p13.1 for cardia (p=7.36x10(-12)) and non-cardia cancers (p=2.42x10(-23)) with per allele OR (95% CI) for the combined endpoint of 0.80 (0.77 to 0.83). At 6p21.1, rs2294693 near UNC5CL was significantly associated with gastric non-cardia cancer risk (p=2.50x10(-8)), with OR (95% CI) of 1.18 (1.12 to 1.26), but there was only a nominal association for cardia cancer (p=1.47x10(-2)). We also confirmed a previously reported association for rs4072037 in MUC1 with p=6.59x10(-8) for total gastric cancer and similar estimates for cardia and non-cardia cancers. Three SNPs in PSCA previously reported to be associated with gastric non-cardia cancer showed no apparent association for cardia cancer. Conclusions Our results suggest that associations for SNPs with gastric cancer show some different results by tumour location in the stomach.</P>

Genetic Polymorphisms of Glutathione S-transferase M1 and Prostate Cancer Risk in Asians: A Meta-analysis of 18 Studies

Hu, Zheng-Hui,Lin, Yi-Wei,Xu, Xin,Chen, Hong,Mao, Ye-Qing,Wu, Jian,Zhu, Yi,Xu, Xiang-Lai,Xie, Li-Ping Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Background: Many studies have investigated associations between the glutathione S-transferase M1 (GSTM1) null polymorphism and risk of prostate cancer, but the impact of GSTM1 in people who live in Asian countries is still unclear owing to inconsistencies across results. Methods: We searched the PubMed, Web of Science, Scopus, Ovid and CNKI databases for studies of associations between the GSTM1 null genotype and risk of prostate cancer in people who live in Asian countries, and estimated summary odds ratios (ORs) with 95% confidence intervals (95% CIs). Results: A total of 18 case-control studies with 2,172 cases and 3,258 controls were included in this meta-analysis, which showed the GSTM1 null genotype to be significantly associated with increased risk of prostate cancer in people who live in Asian countries (random-effects OR=1.74, 95% CI1.44-2.09, P<0.001). Similar results were found in East Asians (OR=1.41; 95% CI: 1.12-1.78; P=0.004) and Caucasians in Asia (OR=2.19; 95% CI: 1.85-2.60; P<0.001). No evidence of publication bias was observed. Conclusions: This meta-analysis of available data suggested that the GSTM1 null genotype does contribute to increased risk of prostate cancer in people who live in Asian countries.

A study on load-sharing structure of multi-stage planetary transmission system

Wei Sun,Xiang Liu,Jing Wei,Aiqiang Zhang,Xin Ding,Xinglong Hu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.4

Unequal load distribution is a crucial factor in decreasing bearing capacity and stability of the planetary transmission system. In thispaper, a dynamical model of two-stage helical planetary gear transmission system is established based on lumped-parameter method andLagrange general function. Nonlinearity of gear tooth backlash and error is taken into account. Four load-sharing structures are proposedto study the load-sharing performance. A method to calculate dynamic sensitivity of load-sharing coefficient to errors is presented thatcan provide a reference to component precision determination in order to make planetary system have a better load distribution. Finally, anumerical method of load-sharing performance is validated by a test. These results provide fundamental basis for multi-stage planetarygear transmission system design.

Expression and Significance of TSGF, CEA and AFP in Patients Before and after Radical Surgery for Colon Cancer

Hu, Yi,Wang, Jing-Liang,Tao, Hai-Tao,Wu, Bai-Shou,Sun, Jin,Cheng, Yao,Dong, Wei-Wei,Li, Rui-Xin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

Objective: To explore the expression and significance of tumor specific growth factor (TSGF), carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP) in cancer tissue and serum of patients with colon cancer. Materials and Methods: Radical surgery for colon cancer was performed on 43 patients with laparoscopu under conditions of general anesthesia. The Elisa method was used to detect the levels of serum TSGF, CEA and AFP before and after radical operation, and cancer tissue underwent TSGF, CEA and AFP immunohistochemistry staining after laparoscopic surgery. The decreased conditions of serum TSGF, CEA and AFP in patients with colon cancer at different levels of differentiation and clinical stagings were analyzed, and the relationships of expression rates between histological types, colon cancer morphology, lymph node metastasis and TSGF, CEA as well as AFP in cancer tissue were assessed. Results: Compared with before radical surgery, the levels of serum TSGF, CEA and AFP decreased notably in patients after operations (p<0.01). The decreased degree of TSGF and CEA was the largest in patients with poorly differentiated cancer tissue (p<0.01), while that of AFP was noted in patients with moderately differentiated cancer tissue (p<0.01). The decreased degree of TSGF and AFP was the largest in patients at phase Dukes A (p<0.01), while that of CEA in patients at phase Dukes C (p<0.01). There were no significant differences among the positive expression rates of TSGF, CEA and AFP with different histological types and colon cancer morphologies (p>0.05). The positive expression rates of TSGF and CEA in patients with lymph node metastasis were significantly higher than those without lymph node metastasis (p<0.01). Conclusions: TSGF, CEA and AFP can be used to evaluate the effect of radical operation for colon cancer, and the changed levels of different markers are associated with tumor differentiation, clinical stating and presence or absence of lymph node metastasis.

Bias load analysis and asymmetric modification of rollers in the main drive bearing of large roadheader

Xin-Qi Wang,Wei Sun,Lintao Wang,Shi-Hu Liang,Xiao-Kai Mu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.6

An asymmetric modification method for the roller profile was proposed to address the bias load effect of rollers in the main drive bearing of a large roadheader. A contact mechanics model of the bearing was solved, and line contact theory was used to explore the effect of combined load and convexity on the bias load effect. The contact stress was found to be asymmetrically distributed along the contact line. This trend tended to be remarkable with the decrease in axial load or the increase in overturning moment. Symmetrically modified rollers can be used to improve the bias load effect by increasing convexity. However, this process led to the contact stress concentrating in the roller center. The influence of the design parameters for asymmetric modification on the roller profile and the contact stress was considered. The ideal design parameters were determined by using a genetic algorithm. The contact condition and fatigue life were remarkably increased.

Internal force monitoring design of long span bridges based on ultimate bearing capacity ratios of structural components

Hu, Ke,Xie, Zheng,Wang, Zuo-Cai,Ren, Wei-Xin,Chen, Lei-Ke Techno-Press 2018 Structural monitoring and maintenance Vol.5 No.1

In order to provide a novel strategy for long-span bridge health monitoring system design, this paper proposes a novel ultimate bearing capacity ratios based bridge internal force monitoring design method. The bridge ultimate bearing capacity analysis theories are briefly described. Then, based on the ultimate bearing capacity of the structural component, the component ultimate bearing capacity ratio, the uniformity of ultimate bearing capacity ratio, and the reference of component ultimate bearing capacity ratio are defined. Based on the defined indices, the high bearing components can then be found, and the internal force monitoring system can be designed. Finally, the proposed method is applied to the bridge health monitoring system design of the second highway bridge of Wuhu Yangtze river. Through the ultimate bearing capacity analysis of the bridge in eight load conditions, the high bearing components are found based on the proposed method. The bridge internal force monitoring system is then preliminary designed. The results show that the proposed method can provide quantitative criteria for sensors layout. The monitoring components based on the proposed method are consistent with the actual failure process of the bridge, and can reduce the monitoring of low bearing components. For the second highway bridge of Wuhu Yangtze river, only 59 components are designed to be monitored their internal forces. Therefore, the bridge internal force monitoring system based on the ultimate bearing capacity ratio can decrease the number of monitored components and the cost of the whole monitoring system.