Wind-induced response of open type hyperbolic-parabolic membrane structures

Junhao Xu,Yingying Zhang,Lanlan Zhang,Meng Wu,Yi Zhou,Ke Lei,Qilin Zhang 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.2

In this paper, the mechanical characteristics of the open type hyperbolic-parabolic membrane structure under wind load were investigated. First, the numerical simulation of a typical plane membrane structure was performed based on the Large-Eddy Simulation method. The accuracy of the simulation method was validated by the corresponding wind tunnel test results. Then, the wind load shape coefficients of open type hyperbolic-parabolic membrane structures are obtained from the series of numerical calculations and compared with the recommended values in the “Technical Specification for Membrane Structures (CECS 158: 2015). Finally, the influences of the wind directions and wind speeds on the mean wind pressure distribution of open type hyperbolic-parabolic membrane structures were investigated. This study aims to gain a better understanding of the wind-induced response for this type of structure and be useful to engineers and researchers.

Experimental Study on Axial Compression of Concrete with Initial Crack under Hydrostatic Pressure

Junhao Chen,Yanlong Li,Lifeng Wen,Peng Bu,Kangping Li 대한토목학회 2020 KSCE Journal of Civil Engineering Vol.24 No.2

The axial compression test of concrete with different initial cracks under hydrostatic pressure is carried out. The fracture propagation is analyzed based on the bearing state as well as the apparent phenomena of the specimens, and the failure modes and morphologies are further elaborated. The test results show that with the increase of the hydrostatic pressure, the peak strength growth rate of different crack dip angle specimens tends to be larger or smaller. The development of the hydrostatic pressure leads to the remarkable growth of the plasticity of initially cracked post-peak plastic specimens. Due to the influence of the crack inclination angle, various rates of variation of the elastic modulus after strain softening are detectable. Under the combinational effects of the crack inclination angle and the hydrostatic pressure, the failure modes of the concrete with different initially inclined cracks are different, leading to fracturing failure and shearing shear failure. The crack propagation morphologies of the initially cracked specimens are also dissimilar. With the increase of the hydrostatic pressure as well as the inclination angle of cracks, the crack propagation pattern gradually changes from I-shaped cracks to II-typed cracks, even I-II composite cracks would appear.

An Automated System for the Creation of an Urban Infrastructure 3D Model using Image Processing Techniques

Junhao Zou,김병일,김형관,M. Al-Hussein 대한토목학회 2012 KSCE JOURNAL OF CIVIL ENGINEERING Vol.16 No.1

Image database creation for infrastructure management is an interdisciplinary endeavor in computer vision, database, and structural engineering. In response to increasing demands for multimedia information in infrastructure management, image databases are becoming an ever more active research area. This paper proposes an automated system for creating an urban infrastructure 3D model using an image database; the system is built by images shot in public areas to record changes of urban infrastructure in threedimensional (3D) space, such as the addition of new buildings, new overpasses, loss of traffic signs, and growth/change of trees. The system architecture is presented with an emphasis on a 3D information capture and extraction module. Initial experiments with the 3D information capture module show that the proposed system has the potential to efficiently develop a large-scale 3D model of the streets of a municipality.

The Developing Economy and Urban Transportation

Li Junhao 대한교통학회 1998 대한교통학회 기타자료 Vol.1998 No.-

Social and economic development needs the support of transportation and communications and in turn the development level of society and economy affects urban traffic demand and determines the investment scale of transportation facilities. In the paper based on the analysis of the evolution of urban transportation in Shanghai in the past ten years and the economic background of that period, the urban transportation in the future development of economy is generally prospected.

An Automated System for the Creation of an Urban Infrastructure 3D Model using Image Processing Techniques

Zou, Junhao,Kim, Byungil,Kim, Hyoungkwan,Al-Hussein, M. 대한토목학회 2012 KSCE Journal of Civil Engineering Vol.16 No.1

Image database creation for infrastructure management is an interdisciplinary endeavor in computer vision, database, and structural engineering. In response to increasing demands for multimedia information in infrastructure management, image databases are becoming an ever more active research area. This paper proposes an automated system for creating an urban infrastructure 3D model using an image database; the system is built by images shot in public areas to record changes of urban infrastructure in three-dimensional (3D) space, such as the addition of new buildings, new overpasses, loss of traffic signs, and growth/change of trees. The system architecture is presented with an emphasis on a 3D information capture and extraction module. Initial experiments with the 3D information capture module show that the proposed system has the potential to efficiently develop a large-scale 3D model of the streets of a municipality.

The Developing Economy and Urban Transportation

Li Junhao 대한교통학회 1998 대한교통학회 기타자료 Vol.1996 No.-

Cascade hydrogenation of n-C16 to produce jet fuel over tandem catalysts of modified ZSM-22

Yi Li,Junhao Sun,Jie Wei,Chao Mu,Yujun Zhao,Shengping Wang,Xinbin Ma 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.111 No.-

ZSM-22 with one-dimensional straight channels and suitable acid properties is widely applied in theselective hydrocracking of long-chain alkanes to produce middle distillate. In this work, the tandem catalystswith two kinds of modified ZSM-22 were employed in series to optimize the distribution of theproduct in the hydrotreatment of n-C16 to produce jet fuel. The yield of linear alkanes with high carbonnumbers was enhanced over the upstream catalyst bed of Pt/L-HZSM-22 with shielded external acid siteswhile the isomerization with less further cracking occurred over the downstream catalyst bed of Pt/Me-HZSM-22 with introduced mesopores. The tandem catalysts can combine the ability of Pt/L-HZSM-22 toproduce heavy n-alkanes and the stronger isomerization performance of Pt/Me-HZSM-22. The highestyield of jet fuel (23 wt.%) can be obtained over the tandem catalysts instead of any individual catalyst. The strategy of the tandem zeolite has been initially verified and proposed to broaden the investigationperspectives of the oil refinery.

Evaluation of Various Escherichia coli Strains for Enhanced Lycopene Production

( Jun Ren ),( Junhao Shen ),( Thi Duc Thai ),( Min-gyun Kim ),( Seung Ho Lee ),( Wonseop Lim ),( Dokyun Na ) 한국미생물생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.7

Lycopene is a carotenoid widely used as a food and feed supplement due to its antioxidant, anti-inflammatory, and anti-cancer functions. Various metabolic engineering strategies have been implemented for high lycopene production in Escherichia coli, and for this purpose it was essential to select and develop an E. coli strain with the highest potency. In this study, we evaluated 16 E. coli strains to determine the best lycopene production host by introducing a lycopene biosynthetic pathway (crtE, crtB, and crtI genes cloned from Deinococcus wulumuqiensis R12 and dxs, dxr, ispA, and idi genes cloned from E. coli). The 16 lycopene strain titers diverged from 0 to 0.141 g/l, with MG1655 demonstrating the highest titer (0.141 g/l), while the SURE and W strains expressed the lowest (0 g/l) in an LB medium. When a 2 × YTg medium replaced the MG1655 culture medium, the titer further escalated to 1.595 g/l. These results substantiate that strain selection is vital in metabolic engineering, and further, that MG1655 is a potent host for producing lycopene and other carotenoids with the same lycopene biosynthetic pathway.

Genome-wide identification of calcium-dependent protein kinases (CDPKs) in pear (Pyrus bretschneideri Rehd) and characterization of their responses to Venturia nashicola infection

Liu Shaohua,Li Junhao,Li Na,Zhou Peng,Li Liulin 한국원예학회 2022 Horticulture, Environment, and Biotechnology Vol.63 No.6

Calcium-dependent protein kinases (CDPKs) play signifi cant roles in response to environmental stresses in plants. However, the CDPK gene family in pear ( Pyrus bretschneideri Rehd) has not been thoroughly explored. In this study, we performed a comprehensive analysis of CDPK family genes in pear, and 30 CDPK genes were identifi ed, unevenly distributed across 13 chromosomes, and predicted to be mainly localized at the plasma membrane. Based on phylogenetic analysis and struc- tural features, the PbCDPKs were classifi ed into four distinct subfamilies. In addition, many putative cis-acting elements responsive to hormones and environmental stresses were identifi ed in the promoter regions. According to RNA-seq data, the majority of PbCDPK genes showed diff erential expression in diff erent pear tissues. After inoculation of plants with the fungus Venturia nashicola , four PbCDPK genes were diff erentially expressed in resistant and susceptible pear cultivars, suggesting that they might play an important role in resistance to the pear scab pathogen. These candidate genes will be subjected to disease resistance and functional analysis in future work. Our results thus provide a genome-wide characterization of CDPK family genes in pear and lay the foundation for further functional analysis.

Dynamic Analysis of Construction Safety Risk and Visual Tracking of Key Factors based on Behavior-based Safety and Building Information Modeling

Pin-Chan Lee,Junhao Wei,Hsin-I Ting,Tzu-Ping Lo,Danbing Long,Luh-Maan Chang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.10

Construction has long been seen as a high-risk industry. Many studies conduct risk management by controlling construction risk indicators, but few studies associate risk indicators with time and space to propose long-term risk management methods. Therefore, this study proposes a dynamic analysis and visual tracking method based on behavior-based safety (BBS). This study establishes a BBS observation checklist and records workers’ unsafe behavior. The risk level of unsafe behavior is then determined by grey clustering model. When a high risk occurs, an improved grey correlation model is used to track key indicators that affect risk. In order to achieve visual risk management, this study develops semantic logic to predefine the relationship between components and space. In schedule simulation of BIM, the key indicators of BBS are transformed into an executable visual inspection between work items, components, and space through ARC. This method makes it easier for construction managers to combine time and space to manage safety risk and to adopt appropriate strategies in a timely manner to improve the efficiency of safety management.