A Quantitative Method for Seismic Robustness of RC Frame Considering Resistance Vulnerability of Column and Storey Drift Ratios

Guohua Sheng,Shengji Jin,Lintao Ma,Quan Bai,Chao Xu,Xiaoyu Wang 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

The concept of seismic robustness is proposed by combining the concept of seismic performance and structural robustness. The existing qualitative, quantitative and evaluation methods of seismic robustness are all direct researched on the whole structure, and the influence mechanism of its internal components on the overall seismic robustness is still unclear. It is very important to establish a clear relationship between component design and structural seismic robustness for the structural design, reinforcement design and final evaluation of structural seismic robustness. Based on this, taking the column as the starting point, a quantitative method for the seismic robustness of RC frame by the seismic robustness index is proposed, which takes into account the resistance vulnerability of column and influence of column on the storey drift ratios (SDRs). In which, the resistance vulnerability is represented by the defined control vulnerability coefficient Pimax, and the influence on the SDRs are represented by the storey drift ratio importance coefficients (SDRCs) . The method not only reflects the essential mechanical properties of the column, but also reflects the effects brought about by different SALs. The feasibility of the method is demonstrated by numerical examples of two types of failures (assuming single column and two columns failure), and four optimization design proposals are proposed for it. The analysis shows that  of the target columns to the floor where the target columns located are obviously greater than those on the remaining floors of the target frame. The seismic robustness index R decreases sharply with the increase of the seismic action level (SAL). R is different compare single column failure with two columns failure under 4 SALs. The most effective way to improve the R of the frame under a certain SAL is to retrofit its control column.

Decreased expression of ATF3, orchestrated by β-catenin/TCF3, miR-17-5p and HOXA11-AS, promoted gastric cancer progression via increased β-catenin and CEMIP

Xie Guohua,Dong ping,Chen Hui,Xu Ling,Liu Yi,Ma Yanhui,Zheng Yingxia,Yang Junyao,Zhou Yunlan,Chen Lei,Shen Lisong 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

ATF3 has been reported to be dysregulated in various cancers and involved in various steps of tumorigenesis. However, the mechanisms underlying the abnormal expression of ATF3 and its biological function in gastric cancer (GC) have not been well investigated. Here, we report ATF3 as one of the key regulators of GC development and progression. Patients with low ATF3 expression had shorter survival and a poorer prognosis. In vitro and in vivo assays investigating ATF3 alterations revealed a complex integrated phenotype that affects cell growth and migration. Strikingly, high-throughput sequencing and microarray analysis of cells with ATF3 silencing or of ATF3-low GC tissues indicated alterations in the Wnt signaling pathway, focal adhesions and adherens junctions. Mechanistically, the expression of β-catenin and cell migration inducing hyaluronidase 1 (CEMIP) was significantly upregulated in GC cells with downregulated ATF3, which was synergistically repressed by the β-catenin/TCF3 signaling axis and noncoding RNA miR-17-5p and HOXA11-AS. In addition, we found that WDR5 expression was promoted by TCF3 and is involved in miR-17-5p and HOXA11-AS activation in GC cells. Taken together, our findings revealed the mechanism of ATF3 downregulation and its biological role in regulating the expression of Wnt signaling-related genes during GC progression, suggesting new informative biomarkers of malignancy and therapeutic directions for GC patients.

Weighing the Evidence of Dividend Initiations

Tianyu Zhu,Guohua Ma,Xu-Shen Zhou 사람과세계경영학회 2011 Global Business and Finance Review Vol.16 No.1

This paper analyzes post-event stock performance based on the strength and the weight of evidence of dividend initiations. The strength refers to how extreme the evidence is; the weight refers to how credible the evidence is. Griffin and Tversky’s (1992) experiments show that people are underconfident when presented with low strength and high weight information and overconfident with high strength and low weight information. This study shows that Griffin and Tversky’s results extend to dividend initiation as well. Portfolios with high strength and low weight overreact to dividend announcement, while portfolios with low strength and high weight underreact. The empirical results in this paper show that the strength-weight model can explain the underreaction-overreaction puzzle and suggests that psychological biases may impact stock performance.

Electrochemical Deposition of γ-MnO2 on Ag/rGO Hybrid Films as Flexible Electrode Materials for Asymmetric Supercapacitor

Shiqing Sun,Yongkun Liu,Guohua Jiang,Bo Yu,Uwamahoro Evariste,Pianpian Ma 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.3

The fl exible electrodes are the essential components for fabricating modern fl exible supercapacitors. In this study, a compositehybrid fi lm integrated with silver nanoparticles (Ag NPs), reduced graphene oxide (rGO) and γ-MnO 2 nanorods asa fl exible electrode has been developed by the electrochemical deposition method. The substrate (rGO) of the electrode notonly provides mechanical stability but also ensures fast electron transfer during charge–discharge. The Ag NPs distributedin electrode provide the electronic channel to enhance the electric conductivity. The γ-MnO 2 electroplated on the surface ofhybrid fi lms further improved the electrochemical performance of them. The resultant γ-MnO 2 /Ag/rGO hybrid fi lms exhibita high specifi c capacitance of 1090.3 F g −1 at current density of 0.3 A g −1 . The asymmetric supercapacitor (ASC) deviceswere further fabricated by γ-MnO 2 /Ag/rGO fi lms as anode and AC/rGO fi lms as cathode electrodes within a wide operatingvoltage of 0–1.7 V. The energy density of obtained ASC devices was 71.8 Wh kg −1 at a power density of 279.4 W kg −1 .

Secure DNP3 Services Scheme in Smart Grid Link Layer Based on GCM-AES

Ye Lu,Tao Feng,Guohua Ma 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.8

This paper defines a new DNP3 link layer frame structure based on the link layer packet characteristics of transmission time requirements and security requirements in substation automation system (SAS). The new frame structure can provide three different work modes: authentication, authorization-encryption, non-authenticated encryption. Then we propose a link-layer security service mechanism in substation automation system based on the GCM-AES, including the session key agreement protocol based on EKE, GMAC-based message authentication protocol, GCM-AES Authentication Encryption-based DNP3 protocol and GCM-AES-based message transform algorithm. Through experimental calculation and analysis, the results show that the new security mechanisms achieve the efficient and safety in substation packets transmission.

Epitaxial Growth of Strain-Induced Ferromagnetic LaCoO3 Thin Films by Simple Sol–Gel Technique

Haifeng Liu,Yuqiao Guo,Ruishi Xie,Guohua Ma 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.3

LaCoO3 (LCO) epitaxial films were grown on (001) LaAlO3 (LAO) substrates by the simple sol– gel technique. X-ray diffraction (XRD) and the cross-section transmission electron microscope (TEM) measurements indicate that single-phase (001) oriented LCO epitaxial films with biaxial compressive strain and elongated distortion of CoO6 octahedrons were grown on (001) LAO successfully. The epitaxial relationship between the LCO film and the LAO substrate is confirmed to be (001)LCO||(001)LAO and [100]LCO||[100]LAO. It is also found that LCO grown on LAO has a larger mean Co–O bond length and unit-cell size, compared with those of polycrystalline film. In addition, the magnetic characterization shows that LCO epitaxial film exhibits an obvious ferromagnetic (FM) transition at TC ~ 85 K, which is different from the nonmagnetic ground state of polycrystalline LCO. Combined with the structural analyses, it reveals that the strain-induced ferromagnetism observed in LCO epitaxial film originates from an increase of the mean Co–O bond length and a suppression of the CoO6 octahedral rotations, which can stabilize higher spin state of Co3+ by a decrease of the eg~t2g gap energy.