Structural Responses of Statically Indeterminate Beams Induced by Soil Spatial Variability

Ning Luo,Zhe Luo 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.5

The effect of the soil spatial variability on the structural assessment is explored in a context of statically indeterminate beams. The differential settlement among the four footings of a continuous beam is probabilistically determined considering various levels of soil spatial variability using the random finite element method. The settlement-induced beam internal forces, in terms of the transverse shear force and bending moment, are solved by using the force method. The variation of shear force and bending moment within a statically indeterminate beam, which is induced by the soil spatial variability, is systematically quantified using this probabilistic framework. This study points to the importance of properly addressing the effect of spatially varied soil conditions on structural design and promotes the integrated geotechnical and structural design.

Improved Performances of AlN/Polyimide Hybrid Film and its Application in Redistribution Layer

Zhe Liu,Guifu Ding,Jiangbo Luo,Wen Lu,Xiaolin Zhao,Ping Cheng,Yanlei Wang 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.5

The AlN/polyimide (PI) hybrid film was studied as thedielectric layer in the redistribution layer (RDL) in this work. The incorporation of the AlN into the PI matrix was achievedby mechanical ball-milling process. The spin-coating processwas used to fabricate the AlN/PI hybrid film, which iscompatible with micro-electro-mechanical system (MEMS)technology for fabricating RDL. The AlN/PI hybrid film wascharacterized by Fourier transform infrared (FTIR) spectrumand thermogravimetric analysis (TGA). The effect of the AlNcontent on the thermal stability, thermal expansion coefficient,hardness and water adsorption of the AlN/PI hybrid film wasstudied. The results indicated that the addition of AlN nanoparticlesimproved the thermal stability and hardness, butdecreased the thermal expansion coefficient and waterabsorption of the pure PI film. As an example of its typicalapplication, the AlN/PI hybrid film with 8 wt.% AlN waspatterned using micromachining technology and used as thedielectric layer in RDL successfully.

In situ growth of hollow Cu2O spheres using anionic vesicles as soft templates

Xiaolin Luo,Zhe Pan,Fei Pei,Zhipeng Jin,Kangkang Miao,Pengfei Yang,Huaming Qian,Qiang Chen,Guodong Feng 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.59 No.-

Geometrically optimizing anionic vesicles were fabricated using two types of anionic surfactants with antipodal molecular configuration. The influence of counterions on the anionic vesicles was systematically investigated to maintain electrostatic interaction between the anionic vesicles and the precursors, as well as to ensure the structural integrity of the vesicle templates. The transcription from vesicles to hollow Cu2O spheres was achieved through an in situ reduction approach. The obtained hollow Cu2O spheres were assembled by abundant nanoparticles around the vesicle interface and showed preferable adsorption capacity for methyl orange in the dark compared with the solid Cu2O spheres synthesized without any surfactants.

Synergic adsorption of acid blue 80 and heavy metal ions (Cu2+/Ni2+) onto activated carbon and its mechanisms

Xinsheng Luo,Ziqiang Lei,Pengxin Zhou,Yani Liu,Guofu Maa,Zhe Zhang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.27 No.-

A novel synergic adsorption process of acid blue 80 dye (AB80) and heavy metal ions (Cu2+ or Ni2+) on alow-cost activated carbon (PRAC) which was prepared from potato residue was reported. The resultsindicated that the maximum adsorption capacity of PRAC for AB80 and Cu2+ were 294.7 mg/g and45.0 mg/g in the AB80-Cu2+ system, respectively. In the mono-component system, the values were173.0 mg/g and 26.8 mg/g, respectively. Compared with mono-component system, the AB80 and Cu2+showed good synergistic effect on PRAC. The similarly result was revealed in the AB80-Ni2+ system. For abinary system, the adsorption isotherm of AB80 and heavy metal ions followed the non-modified Sipsmodel, and the adsorption kinetic models followed the pseudo-second order kinetic model. The effect ofpH also was discussed, and showed significant role in the binary-component system adsorption. Theselectivity in synergic adsorption was discussed. BET, FE-SEM/EDX and XPS were used to characterizePRAC with and without adsorbed dye and heavy metal ions, possible mechanisms of AB80 and heavymetal ions synergic adsorption process were proposed.

Block Tearing and Local Buckling of Aluminum Alloy Gusset Joint Plates

Xiaonong Guo,Zhe Xiong,Yongfeng Luo,Han Xu,Shuiping Liang 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.2

Aluminum Alloy Gusset (AAG) joints widely used in the single-layer latticed shells have a significant application prospect in spatial structures. Unfortunately, studies on the resistance of AAG joints are insufficient, leading to a lack of applicative design methods for this joint system. This paper is devoted to investigate the resistance of AAG joint plates. Firstly, tests on fourteen AAG joint specimens are carried out to explore their collapse modes. Experimental phenomena show that the main collapse modes of AAG joint plates include the block tearing of top plates and the local buckling of bottom plates. Secondly, Finite Element (FE) simulations to investigate the mechanical behavior of AAG joints are performed by means of the non-linear FE code ABAQUS. Thirdly, formulae for predicting the block tearing resistance and the local buckling resistance of AAG joint plates are proposed, which are based on theoretical analyses. Fourthly, test results are of great help in the determination of parameters k and α which are adopted to modify the block tearing resistance and the local buckling resistance respectively. Finally, a comparison of test results verifies that theoretical formulae are applicable. In addition, in order to avoid the block tearing and the local buckling of AAG joint plates, convenient design criteria are provided.

Wing Weight Estimation Considering Constraints of Structural Strength and Stiffness in Aircraft Conceptual design

Chen Bai,Luo Mingqiang,Shen Zhong,Wu Zhe,Man Yiming,Fang Lei 한국항공우주학회 2014 International Journal of Aeronautical and Space Sc Vol.15 No.4

According to the requirement of wing weight estimation and frequent adjustments during aircraft conceptual design, a wing weight estimation method considering the constraints of structural strength and stiffness is proposed to help designers make wing weight estimations rapidly and accurately. This method implements weight predictions on the basis of structure weight optimization with stiffness constraints and strength constraints, which include achievement of wing shape parametric modeling, rapid structure layout, finite element (FE) model automated generation, load calculation, structure analysis, weight optimization, and weight computed based on modeling. A software tool is developed with this wing weight estimation method. This software can realize the whole process of wing weight estimation with the method and the workload of wing weight estimation is reduced because much of the work can be completed by the software. Finally, an example is given to illustrate that this weight estimation method is effective.

Life-Cycle System Reliability-Based Approach for Bridge Pile Foundations under Scour Conditions

Zhongyang Wu,Zhe Luo 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

Due to the soil spatial variability, it is still challenging to quantify the long-term reliability of bridge pile foundations under scour conditions. In this paper, a life-cycle system reliability-based approach that can explicitly address the scour-hole geometry and stress history is presented. The finite difference models implemented with the modified load transfer curves are developed to predict the pile performance. Two serviceability failure modes, settlement failure and lateral deflection failure, are investigated in the reliability analysis. This developed approach provides a new tool for the long-term performance assessment and rehabilitation of bridge pile foundations.

Wing weight estimation considering constraints of structural strength and stiffness in aircraft conceptual design

Bai, Chen,Mingqiang, Luo,Zhong, Shen,Zhe, Wu,Yiming, Man,Lei, Fang The Korean Society for Aeronautical and Space Scie 2014 International Journal of Aeronautical and Space Sc Vol.15 No.4

According to the requirement of wing weight estimation and frequent adjustments during aircraft conceptual design, a wing weight estimation method considering the constraints of structural strength and stiffness is proposed to help designers make wing weight estimations rapidly and accurately. This method implements weight predictions on the basis of structure weight optimization with stiffness constraints and strength constraints, which include achievement of wing shape parametric modeling, rapid structure layout, finite element (FE) model automated generation, load calculation, structure analysis, weight optimization, and weight computed based on modeling. A software tool is developed with this wing weight estimation method. This software can realize the whole process of wing weight estimation with the method and the workload of wing weight estimation is reduced because much of the work can be completed by the software. Finally, an example is given to illustrate that this weight estimation method is effective.

Helmet CPAP versus Oxygen Therapy in Hypoxemic Acute Respiratory Failure: A Meta-Analysis of Randomized Controlled Trials

Xin Chen,Yuwen Luo,Yan Luo,Yun Li,Luqian Zhou,Zhe Zhu,Yitai Chen,Yuxia Huang 연세대학교의과대학 2016 Yonsei medical journal Vol.57 No.4

Purpose: The efficacy of helmet continuous positive airway pressure (CPAP) in hypoxemic acute respiratory failure (hARF) remainsunclear. The aim of this meta-analysis was to critically review studies that investigated the effect of helmet CPAP on gas exchange,mortality, and intubation rate in comparison with standard oxygen therapy. Materials and Methods: We performed a meta-analysis of randomized controlled trials (RCTs) by searching the PubMed, Embase,Cochrane library, OVID, and CBM databases, and the bibliographies of the retrieved articles. Studies that enrolled adults with hARF who were treated with helmet CPAP and measured at least one of the following parameters were included: gas exchange,intubation rate, in-hospital mortality rate. Results: Four studies with 377 subjects met the inclusion criteria and were analyzed. Compared to the standard oxygen therapy, helmet CPAP significantly increased the PaO2/FiO2 [weighted mean difference (WMD)=73.40, 95% confidence interval (95% CI): 43.92 to 102.87, p<0.00001], and decreased the arterial carbon dioxide levels (WMD=-1.92, 95% CI: -3.21 to -0.63, p=0.003), intubationrate [relative risk (RR)=0.21, 95% CI: 0.11 to 0.40, p<0.00001], and in-hospital mortality rate (RR=0.22, 95% CI: 0.09 to 0.50, p=0.0004). Conclusion: The results of this meta-analysis suggest that helmet CPAP improves oxygenation and reduces mortality and intubationrates in hARF. However, the significant clinical and statistical heterogeneity of the literature implies that large RCTs are neededto determine the role of helmet CPAP in different hypoxemic ARF populations.

Genome-wide identification and analysis of long noncoding RNAs in longissimus muscle tissue from Kazakh cattle and Xinjiang brown cattle

Yan, Xiang-Min,Zhang, Zhe,Liu, Jian-Bo,Li, Na,Yang, Guang-Wei,Luo, Dan,Zhang, Yang,Yuan, Bao,Jiang, Hao,Zhang, Jia-Bao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.11

Objective: In recent years, long noncoding RNAs (lncRNAs) have been identified in many species, and some of them have been shown to play important roles in muscle development and myogenesis. However, the differences in lncRNAs between Kazakh cattle and Xinjiang brown cattle remain undefined; therefore, we aimed to confirm whether lncRNAs are differentially expressed in the longissimus dorsi between these two types of cattle and whether differentially expressed lncRNAs regulate muscle differentiation. Methods: We used RNA-seq technology to identify lncRNAs in longissimus muscles from these cattle. The expression of lncRNAs were analyzed using StringTie (1.3.1) in terms of the fragments per kilobase of transcript per million mapped reads values of the encoding genes. The differential expression of the transcripts in the two samples were analyzed using the DESeq R software package. The resulting false discovery rate was controlled by the Benjamini and Hochberg's approach. KOBAS software was utilized to measure the expression of different genes in Kyoto encyclopedia of genes and genomes pathways. We randomly selected eight lncRNA genes and validated them by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Results: We found that 182 lncRNA transcripts, including 102 upregulated and 80 downregulated transcripts, were differentially expressed between Kazakh cattle and Xinjiang brown cattle. The results of RT-qPCR were consistent with the sequencing results. Enrichment analysis and functional annotation of the target genes revealed that the differentially expressed lncRNAs were associated with the mitogen-activated protein kinase, Ras, and phosphatidylinositol 3-kinase (PI3k)/Akt signaling pathways. We also constructed a lncRNA/mRNA coexpression network for the PI3k/Akt signaling pathway. Conclusion: Our study provides insights into cattle muscle-associated lncRNAs and will contribute to a more thorough understanding of the molecular mechanism underlying muscle growth and development in cattle.