Research on feature enhancement method of weak fault signal of rotating machinery based on adaptive stochastic resonance

Kangping Gao,Xinxin Xu,Jiabo Li,Shengjie Jiao,Ning Shi 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.2

Aiming at the problem that the traditional filtering method will filter out some useful signals when extracting weak fault features of rotating machinery, resulting in the loss of characteristic signals, a method for extracting weak fault features based on sin-cosine algorithm (SCA) is proposed. Combining the sensitivity of kurtosis to impact signals and correlation coefficients to interference noise, the paper proposes a new stochastic resonance (SR) performance evaluation index-weighted power spectrum kurtosis (WPSK), which solves the shortcoming of the traditional evaluation index that the fault frequency needs to be known in advance. The structural parameters of the SR are optimized by the SCA to improve the “resonance” effect. The SCA-based SR method is applied to the weak feature extraction of faulty bearings and compared with the SR model of particle swarm optimization, the results show that when the bearing inner-race fails, the value of WPSK increases by 33.5 %, and when the outerrace fails, the value of WPSK increases by 44.1 %.

Ellagic acid exerts anti‑fibrotic effects on hypertrophic scar fibroblasts via inhibition of TGF‑β1/Smad2/3 pathway

Liu Xianjun,Gao Xinxin,Li Hao,Li Zhandong,Wang Xiaoe,Zhang Li,Wang Bo,Chen Xinxin,Meng Xianglong,Yu Jiaao 한국응용생명화학회 2021 Applied Biological Chemistry (Appl Biol Chem) Vol.64 No.5

Hypertrophic scar (HS) is a kind of serious pathological scar with no currently effective treatment. HS fibroblasts (HSFs) are the main effector cells for HS formation. Ellagic acid (EA) exerts regulatory effects in some diseases, but its role in HS remains unclear. This study aimed to evaluate the effect of EA on the fibrotic phenotypes of HSFs and to further investigate the downstream signaling mechanism. The cell counting kit-8 (CCK-8) assay was used to perform cytotoxicity and proliferation assays. HSFs migration was assessed using wound healing and transwell assays. HSFs contraction was measured by a collagen lattice contraction assay and detection of α-smooth muscle actin (α-SMA) expression. The levels of mRNA and protein were determined by qPCR and western blotting, respectively. The results showed that EA inhibited the proliferation, migration, and contraction of HSFs and collagen expression in HSFs in a dose-dependent manner. Furthermore, EA not only suppressed the Smad2/3 pathway but also reversed TGF-β1- induced activation of the Smad2/3 pathway and up-regulation of the fibrotic cellular phenotypes in HSFs. These findings demonstrate that EA exerts anti-fibrotic effects on HSFs by blocking the TGF-β1/Smad2/3 pathway, which indicates that EA is a potential therapeutic candidate for treatment of HS.

基层次分析法的中国生鲜农产品 供应链风险评价体系硏究

邵欣欣(Shao, xinxin),高阔(Gao Kuo),강태원 한중사회과학학회 2019 한중사회과학연구 Vol.17 No.1

In recent years, fresh agricultural products have increasingly become one of the indispensable foods on the table of consumers. However, due to the natural attributes of fresh agricultural products, fresh agricultural supply chain has higher risks than general supply chain. Therefore, it is particularly important to identify and evaluate the risks of fresh agricultural supply chain. This paper firstly combs the relevant domestic and foreign literatures on the risk of fresh agricultural product supply chain. On this basis, on the basis of building the fresh agricultural products supply chain risk evaluation system, involved 4 first-level indicators (demand risk, supply risk, logistics risk, information risk) and 12 secondary indicators, through the questionnaire survey to get the data by using AHP to determine the index weight, and the three different cases of fresh agricultural products supply chain risk assessment analysis, the results showed that: (1) in the risk system of fresh agricultural product supply chain, the weight of demand risk is the largest (0.5174), followed by supply risk (0.2490), logistics risk (0.1279), and information risk (0.1057). (2) among the 12 secondary risk indicator systems, the top six are price fluctuation (0.2753), product quality safety (0.1942), consumer preference (0.1894), delivery delay (0.0627), competition for the same product(0.0527) and information distortion (0.0518). (3) in the case study, the fresh agricultural products supply chain with BoLai agriculture as the core has the strongest risk resistance ability, followed by YiXiangnong and XianKelai. Finally, this paper puts forward some countermeasures and Suggestions from the aspects of supply and demand, logistics technology and mode, informatization and so on. In this paper, the risk assessment system of fresh agricultural supply chain is constructed by combining qualitative and quantitative methods and conducts empirical analysis, which provides theoretical basis for scientific risk avoidance countermeasures and effectively guarantees the continuous and stable operation of fresh agricultural supply chain. 近年来, 生鲜农产品越来越成为消费者餐桌上不可或缺的食物之一, 但由 于生鲜农产品本身的自然属性导致生鲜农产品供应链比一般供应链风险更 高, 因此, 对生鲜农产品供应链风险识别与评价显得尤为重要。本文首先对 生鲜农产品供应链风险的国内外相关文献进行了梳理, 在此基础上构建了生 鲜农产品供应链风险评价体系, 共涉及4个一级指标(需求风险、供应风险、 物流风险、信息风险)和12个二级指标, 其次通过问卷调硏获取数据运用层 次分析法确定指标权重, 幷对三条不同的生鲜农产品供应链进行风险评价的 案例分析, 硏究结果显示: (1)生鲜农产品供应链风险体系中, 需求风险的权 重最大(0.5174), 其次是供应风险(0.2490), 再次物流风险(0.1279), 最后是信 息风险(0.1057);(2)12个二级风险指标体系中, 处于前六位的分别是价格波 动(0.2753)、产品质量安全(0.1942)、消费者偏好(0.1894)、交货延迟(0.062 7)、同产品竞争(0.0527)、信息失眞(0.0518);(3)案例分析中博莱农业为核心 的生鲜农产品供应链抗风险能力最强, 其次是溢香农和仙客来。最后本文从 供需方面、物流技术与模式、信息化等四个方面提出了具有针对性的对策 建议和意见。本文通过定性与定量相结合的方法构建生鲜农产品供应链风 险评价体系幷进行实証分析, 为科学的制定风险规避对策提供了理论依据, 能有效的保障生鲜农产品供应链持续稳定的运作。

Clinical Evidence of Chemotherapy or Endocrine Therapy Maintenance in Patients with Metastatic Breast Cancer: Meta-analysis from Randomized Clinical Trials and Propensity Score Matching of Multicentre Cohort Study

Wei Ren,Yunfang Yu,Huangming Hong,Ying Wang,Quanlong Gao,Yongjian Chen,Peixian Chen,Jianli Zhao,Qiyun Ou,Dagui Lin,Tuping Fu,Yujie Tan,Chenchen Li,Xinxin Xie,Guolin Ye,Jun Tang,Herui Yao 대한암학회 2022 Cancer Research and Treatment Vol.54 No.4

Purpose This study aims to comprehensively evaluate the clinical efficacy of chemotherapy or endocrine therapy maintenance in metastatic breast cancer (MBC) patients. Materials and Methods The meta-analysis of randomized clinical trials (RCTs) and propensity score matching of multicenter cohort study evaluated MBC patients who underwent first-line chemotherapy or endocrine therapy maintenance. This study is registered with PROSPERO: CRD42017071858 and ClinicalTrials.gov: NCT04258163. Results A total of 2,867 patients from 15 RCTs and 760 patients from multicenter cohort were included. The results from meta-analysis showed that chemotherapy maintenance improved progression-free survival (PFS) (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.54 to 0.73; p < 0.001; moderate-quality evidence) and overall survival (OS) (HR, 0.87; 95% CI, 0.78 to 0.97; p=0.016; high-quality evidence) than observation. In the cohort study, for hormone receptor–positive MBC patients, chemotherapy maintenance improved PFS (HR, 0.67; 95% CI, 0.52 to 0.85; p < 0.001) and OS (HR, 0.55; 95% CI, 0.42 to 0.73; p < 0.001) compared with observation, and endocrine therapy maintenance also improved PFS (HR, 0.65; 95% CI, 0.53 to 0.80; p < 0.001) and OS (HR, 0.55; 95% CI, 0.44 to 0.69; p < 0.001). There were no differences between chemotherapy and endocrine therapy maintenance in PFS and OS (all p > 0.05). Regardless of the continuum or switch maintenance therapy, showed prolonged survival in MBC patients who were response to first-line treatment. Conclusion This study provided evidences for survival benefits of chemotherapy and endocrine therapy maintenance in MBC patients, and there was no difference efficacy between chemotherapy and endocrine therapy maintenance for hormone receptor–positive patients.

The Regulation of Phosphorus Release by Penicillium chrysogenum in Different Phosphate via the TCA Cycle and Mycelial Morphology

Wang Liyan,Tian Da,Zhang Xiaoru,Han Mingxue,Cheng Xiaohui,Ye Xinxin,Zhang Chaochun,Gao Hongjian,Li Zhen 한국미생물학회 2023 The journal of microbiology Vol.61 No.8

Phosphate-solubilizing fungi (PSF) efficiently dissolve insoluble phosphates through the production of organic acids. This study investigates the mechanisms of organic acid secretion by PSF, specifically Penicillium chrysogenum, under tricalcium phosphate ( Ca3(PO4)2, Ca–P) and ferric phosphate ( FePO4, Fe–P) conditions. Penicillium chrysogenum exhibited higher phosphorus (P) release efficiency from Ca-P (693.6 mg/L) than from Fe–P (162.6 mg/L). However, Fe–P significantly enhanced oxalic acid (1193.7 mg/L) and citric acid (227.7 mg/L) production by Penicillium chrysogenum compared with Ca–P (905.7 and 3.5 mg/L, respectively). The presence of Fe–P upregulated the expression of genes and activity of enzymes related to the tricarboxylic acid cycle, including pyruvate dehydrogenase and citrate synthase. Additionally, Fe–P upregulated the expression of chitinase and endoglucanase genes, inducing a transformation of Penicillium chrysogenum mycelial morphology from pellet to filamentous. The filamentous morphology exhibited higher efficiency in oxalic acid secretion and P release from Fe–P and Ca–P. Compared with pellet morphology, filamentous morphology enhanced P release capacity by > 40% and > 18% in Ca–P and Fe–P, respectively. This study explored the strategies employed by PSF to improve the dissolution of different insoluble phosphates.

Intelligent identification of mortar void in ballastless slab track using the wheelset acceleration combined with CNN-SVM

Xin Xin,Zunsong Ren,Yi Yin,Jinsheng Gao 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

Mortar void is a hidden defect in ballastless slab track difficult to be efficiently identified by traditional detection methods. This paper is dedicated to proposing a new detection method to identify the mortar void position and length using the vehicle response combined with the hybrid convolutional neural network-support vector machine (CNN-SVM) classifier. The vertical wheelset accelerations with different mortar void conditions are collected from a vehicle-track coupled dynamics simulation model. The first components decomposed from wheelset accelerations by local mean decomposition and their envelopes are utilized as the training data due to their sensitivity to mortar void. To improve the identification precision, the scope descent method is proposed to determine the range influenced by mortar void (IMVR) and samples are labeled according to IMVR. Meanwhile, identification results are post processed based on the mortar void characteristics. The results show that over 90 % mortar void conditions with the length of 0.65 m are detected correctly and the identification has a higher precision with the mortar void length greater than 0.95 m. The proposed technology of mortar void detection using the wheelset accelerations with the hybrid CNN-SVM classifier provides reference for engineering application, which is of great significance to relieve the pressure of health monitoring of railway track.