Driving shaft fatigue optimization design of W type profile twin-screw pumps

Zhi-Jie Liu,Yu-Chong Zhao,Zhi-Qiang Gan,Dong-Lin Hui 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.11

Under changeable pumped medium and working environment, the twin-screw pump is prone to be broken by fatigue failures. A structure optimization design model and method of the driving shaft are presented based on response surface methodology and finite element analysis. In this model, the shaft diameter, chamfering degree and the shaft extension of the power end are selected as optimization variables, the limit values of the variables and maximal normal deformation of the spindle are considered as the constraint conditions, and the minimization of the equivalent alternating stress on the dangerous shaft section is taken as the optimization objective so as to improve the shaft fatigue reliability. The optimization results of a case show that the equivalent alternating stress on the dangerous spindle section reduces by 26.2 %, and the maximal normal deformation decreases by 25.2 % compared with the original design. In addition, the infinite life reliability and fatigue safety factors both meet the design requirements.

Colorimetric Probe Coupled to Dispersive Liquid–Liquid Microextraction for Determination of Dopamine in Serum

Zhi-gang Tai,Yi-ren Zhu,Yi-bo Yuan,Jin Liu,Zhen-jie Li,Zhi-hua Liu,Kun-miao Wang 대한화학회 2020 Bulletin of the Korean Chemical Society Vol.41 No.3

In this work, a highly sensitive method using a colorimetric probe coupled to dispersive liquid?liquid microextraction (DLLME) was developed for the quantitative determination of dopamine (DA) in serum. The DA in serum was concentrated by DLLME to increase the detection sensitivity and reduce the matrix effects. After the DLLME process, a colorimetric probe of silver triangular nanoparticles (AgTNPs) was used to detect DA, which was based on the plasma transformation of AgTNPs caused by strong interactions with melamine (MA). The results showed that DA could inhibit the aggregation of AgTNPs induced by MA, resulting in the recovery of the surface plasmon resonance (SPR) peak of AgTNPs. Thus, the DLLME method followed by colorimetric probe detection of DA can be achieved. The parameters affecting the proposed method were optimized, under the optimal conditions, a linear calibration curve was obtained over a concentration range of 5 to 250?nM with a recovery from 94.4 to 101.3%. The detection limit was 1.6 nM (at an S/N ratio of 3). The present method was successfully applied to determine DA in human serum.

Correlation between population size of pear Psylla (Cacopsylla chinensis) and leaf structure features in different pear cultivars

Sheng-jie Xu,Lun Wu,Qi Zhi Liu,Jun Liu,He Wang,Jie-wen Wang,Ting Zhang 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

The feeding preference of pear psylla (Cacopsylla chinensis) varies among pear cultivars. To clarify whether leaf structural factors are related to C. chinensis resistance, eleven pear cultivars of three pear species and their hybrids in China were studied. The population size of C. chinensis in plots of different cultivars was investigated, and leaf paraffin sections of each pear cultivar were observed. Correlation analysis results showed that the thickness of palisade tissue (PT) and the thickness ratio (TR) of PT to leaf (L) were the main factors influencing resistance to C. chinensis. The leaves of cultivar Wujiuxiang and those species from France and the USA exhibited the thickest PT and the highest TR; these three cultivars demonstrated much higher resistance to C. chinensis than did the other cultivars. The cultivar Gold Nijisseiki, with a large C. chinensis population size, showed low PT and TR. The findings of this study may provide valuable information to pear growers, experts and scientists regarding plant protection, cultivation and breeding when selecting suitable varieties to culture from the perspective of pest control.

Predicting Non Performing Loan of Business Bank with Data Mining Techniques

Wan Jie,Yue Zeng-lei,Yang Dong-hui,ZhangYu,Liu Jiao,Liu Zhi,Liu Jinfu 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.12

The non-performing loans (NPL) prediction plays an important role in business bank. However, there is still a large gap between the requirement of prediction performance and current techniques. In this paper data mining approaches is used to predict the NPL. Both macroeconomic and bank-specific variables are collected to form the feature set firstly. Based on selected features, the study firstly applies single basic classifiers such as decision tree, k nearest neighbors and support vector machine (SVM) to model the problem of NPL. Bagging and AdaBoost are described in this paper as two different method of multiple classifier fusion, to build prediction models. In this experiment, non-performing loans data with 96 features and 10415 instances of a business bank is collected. F-mean and The Area under the ROC Curve (AUC) are considered as metrics of classification. The results illustrate that multiple classifier fusion algorithms outperform single basic classifier. The model built by multiple classifiers fusion can produce better prediction results. Furthermore, the AdaBoost method performs much better than bagging method in processing NPL.

Clinicopathological Features and Prognosis of Gastroenteropancreatic Neuroendocrine Tumors: Analysis from a Single-institution

Zeng, Yu-Jie,Liu, Lu,Wu, Heng,Lai, Wei,Cao, Jie-Zhi,Xu, He-Yang,Wang, Jie,Chu, Zhong-Hua Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Background: The gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN) is the most common type of neuroendocrine neoplasm. We summarized data in our centre to investigate the clinicopathological features, diagnostic methods, therapeutic approaches and prognosis for this neoplasm to increase knowledge of this disease in Asian populations. Method: A total of 122 patients treated at Sun Yet-san Memorial Hospital of Sun Yat-sen University between January 2000 and December 2011 were analyzed retrospectively. Results: Pancreas was the most common site of involvement (65/122, 53.3%); this disease has no special symptoms; positive rates of chromogranin A (CgA) and synaptophysin (Syn) were 81.1% and 87.7%, respectively. The positive rate of Syn had statistical difference among the three grades, but not CgA. Some 68 patients had G1 tumors, 32 G2 tumors and 22 G3 tumors, and Chi-square test showed that higher grading was correlated with worse prognosis (${\chi}^2=32.825$, P=0.0001). A total of 32 patients presented with distant metastasis, and 8 cases emerged during following up. Cox proportional hazards regression modeling showed that the tumor grade (P=0.01), lymphatic metastasis (P=0.025) and distant metastasis (P=0.031) were predictors of unfavorable prognosis. The overall 5-year survival rate was 39.6%, the 5-year survival rate of G1 was 55.7%, and the G2 and G3 were 34.2% and 0%, respectively. Conclusions: The incidence of gastroenteropancreatic neuroendocrine tumors has risen over the last 12 years. All grades of these diseases metastasize readily, and further research regarding the treatment of patients after radical surgery is needed to prolong disease-free survival.

Association of XRCC3 Thr241Met Polymorphisms and Gliomas Risk: Evidence from a Meta-analysis

Liang, Hong-Jie,Yan, Yu-Lan,Liu, Zhi-Ming,Chen, Xu,Peng, Qi-Liu,Wang, Jian,Mo, Cui-Ju,Sui, Jing-Zhe,Wu, Jun-Rong,Zhai, Li-Min,Yang, Shi,Li, Tai-Jie,Li, Ruo-Lin,Li, Shan,Qin, Xue Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

The relationship between the X-ray repair cross-complementing group 3 (XRCC3) Thr241Met polymorphism and gliomas remains inclusive or controversial. For better understanding of the effect of XRCC3 Thr241Met polymorphism on glioma risk, a meta-analysis was performed. All eligible studies were identified through a search of PubMed, Elsevier Science Direct, Excerpta Medica Database (Embase) and Chinese Biomedical Literature Database (CBM) before May 2013. The association between the XRCC3 Thr241Met polymorphism and gliomas risk was conducted by odds ratios (ORs) and 95% confidence intervals (95% CIs). A total of nine case-control studies including 3,533 cases and 4,696 controls were eventually collected. Overall, we found that XRCC3 Thr241Met polymorphism was significantly associated with the risk of gliomas (T vs. C: OR=1.10, 95%CI=1.01-1.20, P=0.034; TT vs. CC: OR=1.30, 95%CI=1.03-1.65, P=0.027; TT vs. TC/CC: OR=1.29, 95%CI=1.01-1.64, P=0.039). In the subgroup analysis based on ethnicity, the significant association was found in Asian under four models (T vs. C: OR=1.17, 95%CI=1.07-1.28, P=0.00; TT vs. CC: OR=1.79, 95%CI=1.36-2.36, P=0.00; TT vs. TC/CC: OR=1.75, 95%CI=1.32-2.32, P=0.00; TT/TC vs. CC: OR=1.11,95% CI=1.02-1.20). This meta-analysis suggested that the XRCC3 Thr241Met polymorphism is a risk factor for gliomas, especially for Asians. Considering the limited sample size and ethnicities included in the meta-analysis, further large scale and well-designed studies are needed to confirm our results.

Corn Peptides Protect Against Thioacetamide-Induced Hepatic Fibrosis in Rats

Jie Lv,Zhi-Kui Nie,Jiu-Liang Zhang,Feng-Yan Liu,Zhenzhen Wang,Zhi-Li Ma,Hui He 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.10

Certain bioactive peptides are reported to be able to alleviate hepatic fibrosis. Our previous work has confirmed the hepatoprotective effect of corn peptides (CPs) that are prepared from a high protein by-product, corn gluten meal, on acute liver injury in an animal model. However, the antifibrotic activity of CPs remained to be elucidated. In this study, the hepatoprotective effect of CPs on thioacetamide (TAA)-induced liver fibrosis was tested. Results showed that CPs (100 mg/kg body weight) significantly decreased the levels of alanine transaminase/aspartate transaminase, laminin, type IV collagen, and type III collagen in serum and increased the serum albumin levels and total antioxidant capacity. Additionally, with CP treatment (100 mg/kg body weight), a significant decrease was observed in the levels of malondialdehyde, nitric oxide, hydroxyproline, transforming growth factor b1, and lactate dehydrogenase activity as well as the liver index, while the activity of superoxidedismutase was significantly increased in livers. The histological and morphological analysis showed that the hepatocyte structure in CP-treated rats was superior to that of TAA-injured rats, and inflammation and fibrosis were also ameliorated. Therefore, CPs can be used as an option for prevention and adjuvant therapy of liver fibrosis.

RB1 Polymorphism Contributes to the Efficacy of Platinum-Taxanes in Advanced Squamous Cell Lung Cancer

Liu, Di,Xu, Wen,Zhang, Zhi-Wei,Qian, Ji,Zheng, Hui,Zhang, Jie,Su, Bo Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Background: RB1 (retinoblastoma 1) was reportedly one of the major determinative factors for sensitivity to taxanes in previous studies. In this study, we investigated the influence of RB1 single nucleotide polymorphisms (SNPs) on the efficacy of platinum-taxane regimens in advanced NSCLC patients. Materials and Methods: 234 cases of patients with advanced NSCLC who were treated with first-line platinum-taxane agents were enrolled in this study. Genomic DNA was extracted from patients' peripheral blood samples using a QIAamp DNA Maxi Kit, and genotyped by iSelect HD Bead-Chip. Results: Regression analyses were conducted through the univariate and multivariate Cox proportional hazards model in the 234 patients. The results showed that of the eight RB1 tagSNPs, only rs4151510 was a positive predictive factor for the advanced NSCLC patients treated with platinum taxanes regimen. The patients with G/G genotype of RB rs4151510 had longer overall survival (OS) than the non-G/G genotype (p=0.018). The histology was also correlated with OS in the whole advanced NSCLC patients. Three tagSNPs of RB1, rs4151510, rs4151465, rs9568036 were significantly associated with OS in the advanced NSCLC patients with squamous cell histology using Kaplan-Meier overall survival analysis stratified by histology. Conclusions: RB1 genomic variants were correlated with the efficacy of platinum-taxanes regimen. RB rs4151510 is an independent factor of the prognosis of NSCLC patients receiving platinum-taxane chemotherapy.

Efficient Complex Matrix Inversion for MIMO OFDM Systems

Zhi Quan,Jie Liu 한국통신학회 2017 Journal of communications and networks Vol.19 No.6

The use of orthogonal frequency-division multiplexing(OFDM) greatly simplifies receiver design in multiple-inputmultiple-output (MIMO) wireless systems when the channel is frequencyselective. Since complex-valued matrix manipulations, suchas matrix inversion, are normally required in MIMO-OFDM systems,the receiver complexity is much higher than that of singleinputsingle-output and single-carrier systems. In this paper, theauthors propose a low-complexity version of matrix inversion byusing the dichotomous coordinate descent (DCD) algorithm forMIMO-OFDM systems. The idea is for the DCD algorithm to separatelyobtain the individual columns of the inverse of the matrix. Owing to the low-complexity hardware implementation of the individualDCD algorithm, a block of DCD processors can be adoptedto obtain the columns of the inverse of the channel correlation matrixin parallel with low hardware occupation.

Post-fi re Behavior of Welded Hollow Spherical Joints Subjected to Eccentric Loads

Jie Lu,Hongbo Liu,Zhi-Hua Chen 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.2

Welded hollow spherical joints are widely used as a connection pattern in space lattice structures. Understanding the postfi re residual behavior of welded hollow spherical joints is crucial for fi re damage assessment of the space lattice structures. However, the post-fi re behavior of welded hollow spherical joints has not been explored in existing studies. In this paper, experimental and numerical studies were conducted to investigate the residual behavior of eccentrically loaded welded hollow spherical joints after fi re exposure. Eccentric compressive tests were performed on fi ve joint specimens after exposure to the ISO-834 standard fi re (including both heating and cooling phases), and three highest fi re temperatures, i.e., 600, 800, and 1000 °C, were considered. The temperature distributions in the specimens during the heating and cooling process and the related mechanical behavior of the specimens, such as load versus longitudinal displacement and rotation responses, load-bearing capacities, and strain distributions, were obtained and analyzed. Finite element analysis (FEA), including both heat transfer and mechanical analysis, were also developed using the ABAQUS software. Having validated the FE models against the experimental results, a design method was proposed on the basis of parametric studies to predict the residual load-bearing capacity of eccentrically loaded welded hollow spherical joints after fi re exposure.