A novel PSO-based algorithm for structural damage detection using Bayesian multi-sample objective function

Ze-Peng Chen,Ling Yu 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.6

Significant improvements to methodologies on structural damage detection (SDD) have emerged in recent years. However, many methods are related to inversion computation which is prone to be ill-posed or ill-conditioning, leading to lowcomputing efficiency or inaccurate results. To explore a more accurate solution with satisfactory efficiency, a PSO-INM algorithm, combining particle swarm optimization (PSO) algorithm and an improved Nelder-Mead method (INM), is proposed to solve multi-sample objective function defined based on Bayesian inference in this study. The PSO-based algorithm, as a heuristic algorithm, is reliable to explore solution to SDD problem converted into a constrained optimization problem in mathematics. And the multi-sample objective function provides a stable pattern under different level of noise. Advantages of multi-sample objective function and its superior over traditional objective function are studied. Numerical simulation results of a two-storey frame structure show that the proposed method is sensitive to multi-damage cases. For further confirming accuracy of the proposed method, the ASCE 4-storey benchmark frame structure subjected to single and multiple damage cases is employed. Different kinds of modal identification methods are utilized to extract structural modal data from noise-contaminating acceleration responses. The illustrated results show that the proposed method is efficient to exact locations and extents of induced damages in structures.

Key challenges, recent advances and future perspectives of rechargeable lithium-sulfur batteries

Ze-Chen Lv,Peng-Fei Wang,Jian-Cang Wang,Shu-Hui Tian,Ting-Feng Yi 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.124 No.-

Lithium-sulfur (Li-S) battery, which releases energy by coupling high abundant sulfur with lithium metal,is considered as a potential substitute for the current lithium-ion battery. Thanks to the lightweight andmulti-electron reaction of sulfur cathode, the Li-S battery can achieve a high theoretical specific capacityof 1675 mAh g1 and specific energy of 2600 Wh kg1. However, some key scientific issues limit its practicalapplication, such as the ‘‘shuttle effect” of lithium polysulfides, large volume change, poor conductivityof sulfur and its solid-state products, and self-discharge phenomenon. Of these, the ‘‘shuttle effect”is recognized as the most critical challenge affecting on electrochemical performance. Hence, this reviewfirst systematically introduces the development of Li-S batteries and the corresponding ‘‘shuttle effect”. Then, the latest work on anode, cathode, separator and electrolyte are summarized. Finally, some promisingviews on the future research direction of this battery system are put forward.

Comprehensive Expression Analysis Suggests Functional Overlapping of Human FOX Transcription Factors in Cancer

Zhang, Ya-Li,Sun, Feng-Ting,Zhang, Ze,Chen, Xiao-Xu,Liu, Ai-Xiang,Pan, Jing-Jing,Peng, Fei,Zhou, Shuai,Sun, Li-Jun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Forkhead-box (FOX) transcription factors comprise a large gene family that contains more than 50 members in man. Extensive studies have revealed that they not only have functions in control of growth and development, but also play important roles in different diseases, especially in cancer. However, biological functions for most of the members in the FOX family remain unknown. In the present study, the expression of 39 FOX genes in 48 kinds of cancer was mined from the Gene Expression Atlas database of European Bioinformatics Institute. The analysis results showed that some FOX genes demonstrate overlapping expression in various cancers, which suggests particular biological functions. The pleiotropic features of the FOX genes make them excellent candidates in efforts aimed to give medical treatment for cancers at the genetic level. The results also indicated that different FOX genes may have the synergy or antagonistics effects in the same cancers. The study provides clues for further functional analysis of FOX genes, especially for the pleiotropic biological functions and crosstalk of FOX genes in human cancers.

A hybrid self-adaptive Firefly-Nelder-Mead algorithm for structural damage detection

Chu-Dong Pan,Ling Yu,Ze-Peng Chen,Wen-Feng Luo,Huan-Lin Liu 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.17 No.6

Structural damage detection (SDD) is a challenging task in the flied of structural health monitoring (SHM). As an exploring attempt to the SDD problem, a hybrid self-adaptive Firefly-Nelder-Mead (SA-FNM) algorithm is proposed for the SDD problem in this study. First of all, the basic principle of firefly algorithm (FA) is introduced. The Nelder-Mead (NM) algorithm is incorporated into FA for improving the local searching ability. A new strategy for exchanging the information in the firefly group is introduced into SA-FNM for reducing the computation cost. A random walk strategy for the best firefly and a self-adaptive control strategy of three key parameters,such as light absorption, randomization parameter and critical distance, are proposed for preferably balancing the exploitation and exploration ability of the SA-FNM. The computing performance of the SA-FNM is evaluated and compared with the basic FA by three benchmark functions. Secondly, the SDD problem is mathematically converted into a constrained optimization problem, which is then hopefully solved by the SA-FNM algorithm. A multi-step method is proposed for finding the minimum fitness with a big probability. In order to assess the accuracy and the feasibility of the proposed method, a two-storey rigid frame structure without considering the finite element model (FEM) error and a steel beam with considering the model error are taken examples for numerical simulations. Finally, a series of experimental studies on damage detection of a steel beam with four damage patterns are performed in laboratory. The illustrated results show that the proposed method can accurately identify the structural damage. Some valuable conclusions are made and related issues are discussed as well.

Radioactive gas diffusion simulation and inhaled effective dose evaluation during nuclear decommissioning

Li-qun Yang,Yong-kuo Liu,Min-jun Peng,Abiodun Ayodeji,Zhi-tao Chen,Ze-yu Long 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.1

During the decommissioning of the nuclear facilities, the radioactive gases in pressure vessels may leakdue to the demolition operations. The decommissioning site has large space, slow air circulation, andmany large nuclear facilities, which increase the difficulty of workers' inhalation exposure assessment. Inorder to dynamically evaluate the activity distribution of radionuclides and the committed effective dosefrom inhalation in nuclear decommissioning environment, an inhalation exposure assessment methodbased on the modified eddy-diffusion model and the inhaled dose conversion factor is proposed in thispaper. The method takes into account the influence of building, facilities, exhaust ducts, etc. on thedistribution of radioactive gases, and can evaluate the influence of radioactive gases diffusion on workersduring the decommissioning of nuclear facilities.

MiR-1224-5p modulates osteogenesis by coordinating osteoblast/osteoclast differentiation via the Rap1 signaling target ADCY2

Hu Liangcong,Xie Xudong,Xue Hang,Wang Tiantian,Panayi Adriana C.,Lin Ze,Xiong Yuan,Cao Faqi,Yan Chengcheng,Chen Lang,Cheng Peng,Zha Kangkang,Sun Yun,Liu Guodong,Yu Chenyan,Hu Yiqiang,Tao Ranyang,Zhou 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

MicroRNAs (miRNAs) broadly regulate normal biological functions of bone and the progression of fracture healing and osteoporosis. Recently, it has been reported that miR-1224-5p in fracture plasma is a potential therapy for osteogenesis. To investigate the roles of miR-1224-5p and the Rap1 signaling pathway in fracture healing and osteoporosis development and progression, we used BMMs, BMSCs, and skull osteoblast precursor cells for in vitro osteogenesis and osteoclastogenesis studies. Osteoblastogenesis and osteoclastogenesis were detected by ALP, ARS, and TRAP staining and bone slice resorption pit assays. The miR-1224-5p target gene was assessed by siRNA-mediated target gene knockdown and luciferase reporter assays. To explore the Rap1 pathway, we performed high-throughput sequencing, western blotting, RT-PCR, chromatin immunoprecipitation assays and immunohistochemical staining. In vivo, bone healing was judged by the cortical femoral defect, cranial bone defect and femoral fracture models. Progression of osteoporosis was evaluated by an ovariectomy model and an aged osteoporosis model. We discovered that the expression of miR-1224-5p was positively correlated with fracture healing progression. Moreover, in vitro, overexpression of miR-1224-5p slowed Rankl-induced osteoclast differentiation and promoted osteoblast differentiation via the Rap1-signaling pathway by targeting ADCY2. In addition, in vivo overexpression of miR-1224-5p significantly promoted fracture healing and ameliorated the progression of osteoporosis caused by estrogen deficiency or aging. Furthermore, knockdown of miRNA-1224-5p inhibited bone regeneration in mice and accelerated the progression of osteoporosis in elderly mice. Taken together, these results identify miR-1224-5p as a key bone osteogenic regulator, which may be a potential therapeutic target for osteoporosis and fracture nonunion.

Variation of Urinary and Serum Trace Elements (Ca, Zn, Cu, Se) in Bladder Carcinoma in China

Guo, Kun-Feng,Zhang, Zhe,Wang, Jun-Yong,Gao, Sheng-Lin,Liu, Jiao,Zhan, Bo,Chen, Zhi-Peng,Kong, Chui-Ze Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Backgrounds: Deficiency or excess of trace elements can induce body metabolic disorders and cellular growth disturbance, even mutation and cancerization. Since there are few studies of the effect of trace elements in bladder carcinoma in China, the aim of this study was thus to assess variation using a case control approach. Methods: To determine this, 81 patients with bladder carcinoma chosen as a study group and 130 healthy persons chosen as a control group were all assayed for urinary and serum trace elements (calcium [Ca], zinc [Zn], copper [Cu], selenium [Se]) using an atomic absorption spectrophotometer, and the results were analyzed by independent sample t tests. The correlative factors on questionnaires answered by all persons were analyzed by logistic regression. Results: The results showed urinary Ca, Zn and serum Cu levels of the study group to be significantly higher (P<0.05) than those of he control group. Serum Ca and Se levels of study group were significantly lower (P<0.05) than those of control group. Conclusion: There were higher urinary Zn and serum Cu concentrations in bladder carcinoma cases. Bladder carcinoma may be associated with Ca metabolic disorder, leading to higher urinary Ca and lower serum Ca. Low serum Se and smoking appear to be other risk factors for bladder carcinoma in China.