Wind-induced responses of supertall buildings considering soil-structure interaction

Huang, Yajun,Gu, Ming Techno-Press 2018 Wind and Structures, An International Journal (WAS Vol.27 No.4

In this study, a simplified three-dimensional calculation model is developed for the dynamic analysis of soil-pile group-supertall building systems excited by wind loads using the substructure method. Wind loads acting on a 300-m building in different wind directions and terrain conditions are obtained from synchronous pressure measurements conducted in a wind tunnel. The effects of soil-structure interaction (SSI) on the first natural frequency, wind-induced static displacement, root mean square (RMS) of displacement, and RMS of acceleration at the top of supertall buildings are analyzed. The findings demonstrate that with decreasing soil shear wave velocity, the first natural frequency decreases and the static displacement, RMS of displacement and RMS of acceleration increase. In addition, as soil material damping decreases, the RMS of displacement and the RMS of acceleration increase.

Wind-induced responses of supertall buildings considering soil-structure interaction

Yajun Huang,Ming Gu 한국풍공학회 2018 Wind and Structures, An International Journal (WAS Vol.27 No.4

In this study, a simplified three-dimensional calculation model is developed for the dynamic analysis of soil-pile group-supertall building systems excited by wind loads using the substructure method. Wind loads acting on a 300-m building in different wind directions and terrain conditions are obtained from synchronous pressure measurements conducted in a wind tunnel. The effects of soil-structure interaction (SSI) on the first natural frequency, wind-induced static displacement, root mean square (RMS) of displacement, and RMS of acceleration at the top of supertall buildings are analyzed. The findings demonstrate that with decreasing soil shear wave velocity, the first natural frequency decreases and the static displacement, RMS of displacement and RMS of acceleration increase. In addition, as soil material damping decreases, the RMS of displacement and the RMS of acceleration increase.

Secure Transmission Scheme Based on the Artificial Noise in D2D-Enabled Full-Duplex Cellular Networks

( Chen Yajun ),( Yi Ming ),( Zhong Zhou ),( Ma Keming ),( Huang Kaizhi ),( Ji Xinsheng ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.10

In this paper, a secure transmission scheme based on the artificial noise is proposed for D2D communications underlaying the full-duplex cellular network, and a secure power allocation scheme to maximize the overall secrecy rate of both the cellular user and D2D transmitter node is presented. Firstly, the full-duplex base station transmits the artificial noise to guarantee the secure communications when it receives signals of cellular uplinks. Under this secure framework, it is found that improving the transmission power of the cellular user or the D2D transmitter node will degrade the secrecy rate of the other, although will improve itself secrecy rate obviously. Hence, a secure power allocation scheme to maximize the overall secrecy rate is presented subject to the security requirement of the cellular user. However, the original power optimization problem is non-convex. To efficiently solve it, we recast the original problem into a convex program problem by utilizing the proper relaxation and the successive convex approximation algorithm. Simulation results evaluate the effectiveness of the proposed scheme.

High-Conductivity SiO2-Matrix B-Doped Si-NC Thin Films by Following Ion-Beam Treatment

Junjun Huang,Weiyan Wang,Jie Yang,Yongzhen Tan,Wei Chen,Tianyu Ge,Yajun Zhang,Min Gao,Zhenming Chen 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.6

In this work, further ion-beam was performed on SiO2-matrix B-doped Si-NC (SBC) thin films in order to enhance conductivity. The effect of ionbeamtype on the electrical properties of SBC thin films was investigatedsystematically. The results indicated that the conductivities of SBC thinfilms were significantly improved by both argon and hydrogen ion-beamtreatments, and the higher the hydrogen ion ratio, the higher theconductivity of SBC thin films. The conductivity of SBC thin films wasincreased from 1.82 × 10−6 S/cm to 3.2 × 10−3 S/cm with followinghydrogen-ion-beam treatment. The change in conductivity of SBC thinfilms was most possibly resultant from the ion-beam treatment facilitatingthe formation of higher superficial order and lower defects. An alternativemethod was proposed to prepare high-conductivity SBC thin films, whichmay be applied to other heterogeneous thin films.

Vagococcus zengguangii sp. nov., isolated from yak faeces

Ge Yajun,Jin Dong,Lai Xin-He,Yang Jing,Lu Shan,Huang Ying,Zheng Han,Zhang Xiaoyan,Xu Jianguo 한국미생물학회 2021 The journal of microbiology Vol.59 No.1

Two unknown Gram-stain-positive, catalase- and oxidasenegative, non-motile, and coccus-shaped bacteria, designated MN-17T and MN-09, were isolated from yaks faeces (Bos grunniens) in the Qinghai-Tibet Plateau of China. 16S rRNA gene sequence-based comparative analyses revealed that the two strains were grouped within the genus Vagococcus, displaying the highest similarity with Vagococcus xieshaowenii CGMCC 1.16436T (98.6%) and Vagococcus elongatus CCUG 51432T (96.4%). Both strains grew optimally at 37°C and pH 7.0 in the presence of 0.5% (w/v) NaCl. The complete genome of MN-17T comprises 2,085 putative genes with a total of 2,190,262 bp and an average G + C content of 36.7 mol%. The major fatty acids were C16:0 (31.2%), C14:0 (28.5%), and C18:1ω9c (13.0%); the predominant respiratory quinone was MK-7 (68.8%); the peptidoglycan type was A4α(L-Lys-DAsp); and the major polar lipid was diphosphatidylglycerol. Together, these supported the affiliation of strain MN-17T to the genus Vagococcus. In silico DNA-DNA hybridization and the average nucleotide identity values between MN-17T and all recognized species in the genus were 21.6–26.1% and 70.7–83.0%, respectively. MN-17T produced acid from D-cellobiose, D-fructose, glycerol, D-glucose, N-acetyl-glucosamine, gentiobiose, D-mannose, D-maltose, D-ribose, Dsaccharose, salicin, D-trehalose, and D-xylose. These results distinguished MN-17T and MN-09 from closely related species in Vagococcus. Thus, we propose that strains MN-17T and MN-09 represent a novel species in the genus Vagococcus, with the name Vagococcus zengguangii sp. The type strain is MN-17T (= CGMCC 1.16726T = GDMCC 1.1589T = JCM 33478T).

CoMP Transmission for Safeguarding Dense Heterogeneous Networks with Imperfect CSI

( Xu Yunjia ),( Huang Kaizhi ),( Hu Xin ),( Zou Yi ),( Chen Yajun ),( Jiang Wenyu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.1

To ensure reliable and secure communication in heterogeneous cellular network (HCN) with imperfect channel state information (CSI), we proposed a coordinated multipoint (CoMP) transmission scheme based on dual-threshold optimization, in which only base stations (BSs) with good channel conditions are selected for transmission. First, we present a candidate BSs formation policy to increase access efficiency, which provides a candidate region of serving BSs. Then, we design a CoMP networking strategy to select serving BSs from the set of candidate BSs, which degrades the influence of channel estimation errors and guarantees qualities of communication links. Finally, we analyze the performance of the proposed scheme, and present a dual-threshold optimization model to further support the performance. Numerical results are presented to verify our theoretical analysis, which draw a conclusion that the CoMP transmission scheme can ensure reliable and secure communication in dense HCNs with imperfect CSI.

Optimization Strategy on Conformal Polishing of Precision Optics using Bonnet Tool

Ri Pan,Yajun Zhang,Jianbiao Ding,Changqing Huang,Zhenzhong Wang 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.5

For the purpose of optimizing the polishing process of ultra-precision optics, the optimal motion for bonnet tool used in conformal polishing (CP) is investigated. Firstly, the removal mechanism in CP was studied and analyzed, based on which the conformal polishing conditions (CPC) and the conclusion that sub-steps precession (S-s-P) is the optimal motion were obtained; After that, corresponding simulations and experiments were conducted, and the results revealed that (1) the ability for CP of continuous precession (Con-P) was not stable, and only when the round distance S and the total polishing length are sufficiently tiny and large, meanwhile, S / vfx = 2*π/ωA is satisfied, the conformal polishing performance of Con-P is good. However, these requirements would limit its application in engineering; (2) Both the incline polishing (IP) and S-s-P models have good performance on CP, and their abilities for CP were not affected by the feeding speed. However, since the texture of the polished area of IP is not so good as S-s-P, the later is the most favourite model in CP. All the results have proven the correctness of the CPC and the theoretical conclusion, which is useful for the engineering application of S-s-P model of bonnet tool.

Optimization Strategy on Conformal Polishing of Precision Optics using Bonnet Tool

Ri Pan,Yajun Zhang,Jianbiao Ding,Changqing Huang,Zhenzhong Wang 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.3

For the purpose of optimizing the polishing process of ultra-precision optics, the optimal motion for bonnet tool used in conformal polishing (CP) is investigated. Firstly, the removal mechanism in CP was studied and analyzed, based on which the conformal polishing conditions (CPC) and the conclusion that sub-steps precession (S-s-P) is the optimal motion were obtained; After that, corresponding simulations and experiments were conducted, and the results revealed that (1) the ability for CP of continuous precession (Con-P) was not stable, and only when the round distance S and the total polishing length are sufficiently tiny and large, meanwhile, S / vfx = 2*π/ωA is satisfied, the conformal polishing performance of Con-P is good. However, these requirements would limit its application in engineering; (2) Both the incline polishing (IP) and S-s-P models have good performance on CP, and their abilities for CP were not affected by the feeding speed. However, since the texture of the polished area of IP is not so good as S-s- P, the later is the most favourite model in CP. All the results have proven the correctness of the CPC and the theoretical conclusion, which is useful for the engineering application of S-s-P model of bonnet tool.

A Joint Design for Multi-band Heterogeneous Networks when Deploying Reconfigurable Intelligent Surface

Wenyu Jiang,Kaizhi Huang,Yajun Chen,Xiaoli Sun,Jie Yang,Kai Zhao 한국통신학회 2022 Journal of communications and networks Vol.24 No.5

Reconfigurable Intelligent Surface (RIS) technique is effective to improve the capacity and coverage of various networks. However, the practical RIS has dissimilar responses to signals in different frequencies due to its structure. Therefore, directly applying existing schemes to multi-band heterogeneous networks leads to beam misalignment and performance degra- dation issues. This paper considers RIS-assisted multi-band heterogeneous networks where base stations (BSs) use different frequencies. We formulate the problem for maximizing the sum rate of all users (SR) in every frequency band, and aim to jointly design BSs precoding vectors and RIS parameters while taking user choices into account. Based on the closed-form relationship of phase shifts between frequencies, an iterative algo- rithm is proposed to solve the challenging non-convex problems. In particular, we use fractional programming to decouple the problem, and solve the subproblems with Quadratic Transform (QT) and Genetic Algorithm (GA). Simulation results show that the proposed scheme can significantly improve SR among all frequency bands, which could instruct the coexistence of mul- tiple communication systems in future heterogeneous networks. What’s more, results also prove that deploying RISs recklessly will result in a degradation of the network.

Long non-coding RNA RP11-6O2.4 indicates poor prognosis and suppresses cell cycle progression through the p38-MAPK signaling pathway in gastric cancer

Yang Feng,Zhiming Fu,Yajun Luo,Wang Tan,Zilin Liu,Pengcheng Ye,Fei Lu,Wanping Xiang,Linghan Tang,Lin Yao,Mengyun Song,Qingmei Huang,Yilun Liu,Jiangwei Xiao 대한독성 유전단백체 학회 2019 Molecular & cellular toxicology Vol.15 No.3

Backgrounds: The role of long non-coding RNAs (lncRNA) in gastric cancer (GC) has been highlighted in studies conducted over the past decade. However, the potential clinical value and the mechanisms of action of RP11-6O2.4 in GC have not been thoroughly elucidated to date. The specific aim of the present study was to assess RP11-6O2.4 and to explore its role in human GC. Methods: Quantitative real-time polymerase chain reaction (qPCR) was performed to analyze the expression levels of RP11-6O2.4 in GC tissues, paired adjacent noncancerous tissues (ANTs) and GC cell lines. In addition, the correlation between RP11-6O2.4 expression and the clinical characteristics and prognosis of patients with GC was statistically analyzed. The effects of RP11- 6O2.4 on the GC cell cycle transformation through the p38-MAPK signaling pathway were explored by flow cytometry, qPCR and Western blot analysis after treatment with SB203580, a p38MAPK specific inhibitor, in vitro. Results: The expression levels of RP11-6O2.4 in GC tissues were significantly lower than the paired ANTs (P<0.05). In addition, RP11-6O2.4 expression was significantly lower in cases with older age, longer maximum tumor diameter, higher ASA grade and deeper invasive depth (P<0.05). RP11-6O2.4 expression was significantly higher in cases with well/middle differentiation than poor/no differentiation; higher in cases without lymph node metastasis than in lymph node metastasis; and higher in cases in stage Ⅰ/Ⅱ than in stage Ⅲ/Ⅳ. An in vitro assay showed that RP11-6O2.4 induced G0/ G1 phase cell cycle arrest, likely by regulating the p38- MAPK signaling pathway. Conclusion: The above mentioned data suggested that RP11-6O2.4 was a tumor-suppressor gene in GC. RP11- 6O2.4 might play an important role in the cell cycle transformation by regulating the p38-MAPK signaling pathway, thereby representing a specific biomarker and a potential molecular target for the treatment of GC.