Three-Dimensional Stability of Cyclical Footage Area in Tunnel Face

Qiao Liang,Jie Liu,Jun Wang,Xian-Tao Zeng,Shuo-Guo Wu 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.2

Based on the theory of limit and the unified strength theory, the three-dimensional failure pattern and the corresponding velocity field on the heading face for cyclical footage are proposed, considering the influence of the cyclical footage and the intermediate principle stress on the heading face stability. Addition, the influence of various parameters on the heading face stability is analyzed. The present study shows that the first increase in internal friction angle (lower than 25°) can promote the heading face stability. Then, the increase in the cohesion can promote the stability when the internal friction angle is higher than 25°. In addition, for the relatively intact instead of the poor surrounding rock, the promotion of the stress conditions of the heading face, caused by by the intermediate principle stress, indicates that the Mohr-Coulomb criterion is conservative.

Suppression of the Epidermal Growth Factor-like Domain 7 and Inhibition of Migration and Epithelial-Mesenchymal Transition in Human Pancreatic Cancer PANC-1 Cells

Wang, Yun-Liang,Dong, Feng-Lin,Yang, Jian,Li, Zhi,Zhi, Qiao-Ming,Zhao, Xin,Yang, Yong,Li, De-Chun,Shen, Xiao-Chun,Zhou, Jin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Background: Epidermal growth factor-like domain multiple 7 (EGFL7), a secreted protein specifically expressed by endothelial cells during embryogenesis, recently was identified as a critical gene in tumor metastasis. Epithelial-mesenchymal transition (EMT) was found to be closely related with tumor progression. Accordingly, it is important to investigate the migration and EMT change after knock-down of EGFL7 gene expression in human pancreatic cancer cells. Materials and Methods: EGFL7 expression was firstly testified in 4 pancreatic cancer cell lines by real-time polymerase chain reaction (Real-time PCR) and western blot, and the highest expression of EGFL7 was found in PANC-1 cell line. Then, PANC-1 cells transfected with small interference RNA (siRNA) of EGFL7 using plasmid vector were named si-PANC-1, while transfected with negative control plasmid vector were called NC-PANC-1. Transwell assay was used to analyze the migration of PANC-1 cells. Real-time PCR and western blotting were used to detect the expression change of EGFL7 gene, EMT markers like E-Cadherin, N-Cadherin, Vimentin, Fibronectin and transcription factors like snail, slug in PANC-1, NCPANC-1, and si-PANC-1 cells, respectively. Results: After successful plasmid transfection, EGFL7 gene were dramatically knock-down by RNA interference in si-PANC-1 group. Meanwhile, migration ability decreased significantly, compared with PANC-1 and NC-PANC-1 group. Meanwhile, the expression of epithelial phenotype marker E-Cadherin increased and that of mesenchymal phenotype markers N-Cadherin, Vimentin, Fibronectin dramatically decreased in si-PANC-1 group, indicating a reversion of EMT. Also, transcription factors snail and slug decreased significantly after RNA interference. Conclusions: Current study suggested that highly-expressed EGFL7 promotes migration of PANC-1 cells and acts through transcription factors snail and slug to induce EMT, and further study is needed to confirm this issue.

The Optimization Model and Algorithm of Remanufacturing Supply Chain Logistics Network with Option Contracts

Liang Yong,Qiao Peili,Luo Zhiyong,Wang Jian 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.8

By the point of view of remanufacturing enterprise, the studies of supply chain logistics network optimization problem focused on network optimization and logistics distribution between manufacturing enterprise and customer area. The present business environment is full of uncertainties. To compete effectively in such an environment, remanufacturing enterprises need to develop the capability of responding flexibly to changing market conditions and optimize effectively logistics networks. The mechanism of option contracts has effectively coordinated the relationship of remanufacturing enterprise and retailer and hedged against the risks of over- and under-production. There is few papers considers the mechanism of option contracts although there are lots of studies on supply chain logistics networks optimization problem. Therefore, the mechanism of option contracts is led into the study of remanufacturing supply chain logistics networks optimization problem. Considering environmental pollution influence factors in the remanufacturing process, a multi-objective optimization model of supply chain is developed. Dual-layer genetic algorithm mechanism was brought up. The first layer is responsible for supply chain logistics network structure with genetic algorithm. The second layer answers for specific supply chain logistics distribution with adaptive immune genetic algorithm. Finally, numerical examples demonstrate the validity of the model and algorithm for the optimization problem.

Comparative study on the high frequency performances of the easy-plane FeNi@SiO2 powder soft magnetic composite

Wang Guowu,Zhang Junming,Zheng Zuying,Qiao Liang,Wang Tao,Li Fashen 한국물리학회 2022 Current Applied Physics Vol.41 No.-

In this work, an easy-plane FeNi@SiO2 powder soft magnetic composite (SMC) was imitated and fabricated and its high frequency magnetic properties were comparatively investigated with a non-easy-plane composite. Due to the planar distribution of easy magnetization axes, the easy-plane composite exhibits a constant permeability of 38 up to 100 MHz. Moreover, the easy-plane SMC exhibits a lower core loss at higher frequencies. Loss separated results show that the hysteresis loss plays a dominant loss component in the composite, rather than dominant excess loss in the non-easy-plane powder composite. These results indicate that, compared with non-easy-plane powder composite, the easy-plane powder composites exhibit comprehensive advantages of higher permeability, wider effective operating frequencies and lower loss, which suggest that the use of easy-plane ferromagnetic powder is a promising and efficient measure to develop a new generation of soft magnetic composites for higher frequency application.

Research on Contamination-Resistant SiO2 Optical Thin Films in a Vacuum Environment

Wang Sheng-zhao,Nan Chun-juan,Qiao Jian-liang,Guo Xin-feng 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.1

The Contamination resistance of SiO2 optical films prepared by using sol-gel method was investigated and improved in this research. FDTS (1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane) was used to modify SiO2 thin films. Fourier Transform Infrared Spectrometer (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used to evaluate the components on surface of the SiO2 thin films. The optical properties and hydrophobicity were also measured. The results show that the SiO2 thin film modification with FDTS causes -OH groups to be replaced by organic groups containing fluorine. The transmittance peak of SiO2 thin film changes, and the surface contact angle of water droplets on the SiO2 film increases from 35° to 107° after surface modification with FTDS. After the SiO2 thin films had been put in a vacuum environment for 24 hours, the peak transmittance of the modified SiO2 film under the same conditions is reduced to 0.14%, which is less than 3.17% of the unmodified film. The peak transmittance of the modified SiO2 thin films is also improved.

Seismic performance analysis of steel-brace RC frame using topology optimization

Shengfang Qiao,Huqing Liang,Mengxiong Tang,Wanying Wang,Hesong Hu 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.71 No.4

Seismic performance analysis of steel-brace reinforced concrete (RC) frame using topology optimization in highly seismic region was discussed in this research. Topology optimization based on truss-like material model was used, which was to minimum volume in full-stress method. Optimized bracing systems of low-rise, mid-rise and high-rise RC frames were established, and optimized bracing systems of substructure were also gained under different constraint conditions. Thereafter, different structure models based on optimized bracing systems were proposed and applied. Last, structural strength, structural stiffness, structural ductility, collapse resistant capacity, collapse probability and demolition probability were studied. Moreover, the brace buckling was discussed. The results show that bracing system of RC frame could be derived using topology optimization, and bracing system based on truss-like model could help to resolve numerical instabilities. Bracing system of topology optimization was more effective to enhance structural stiffness and strength, especially in mid-rise and high-rise frames. Moreover, bracing system of topology optimization contributes to increase collapse resistant capacity, as well as reduces collapse probability and accumulated demolition probability. However, brace buckling might weaken beneficial effects.

Maxillary protraction using customized mini-plates for anchorage in an adolescent girl with skeletal Class III malocclusion

Shuran Liang,Xianju Xie,Fan Wang,Qiao Chang,Hongmei Wang,Yuxing Bai 대한치과교정학회 2020 대한치과교정학회지 Vol.50 No.5

The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized miniplates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400–500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

Layered double hydroxides/oxidized carbon nanotube nanocomposites for CO2 capture

Junya Wang,Liang Huang,Qianwen Zheng,Yaqian Qiao,Qiang Wang 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.36 No.-

A systematic investigation on the influence of synthesis method and chemical composition of LDH/oxidized carbon nanotube (LDH/OCNT) nanocomposites on their CO2 capture performance wereperformed. Three LDH/OCNT nanocomposites were prepared using two methods: ‘‘electrostatic selfassembly’’and ‘‘direct co-precipitation’’. All LDH/OCNT nanocomposites were thoroughly characterized. The isothermal CO2 adsorption at different temperatures (60–400 8C) and adsorption/desorption cyclingtests were conducted. Both the CO2 adsorption capacity and the multi-cycle stability of LDH derivedadsorbents were improved by the introduction of OCNT. In particular, the absolute CO2 capture capacityof Mg-Al-NO3 LDH was increased by more than twice by adding 9.1 wt% OCNT.

Three-dimensional finite element analysis on the effects of maxillary protraction with an individual titanium plate at multiple directions and locations

Fan Wang,Qiao Chang,Shuran Liang,Yuxing Bai 대한치과교정학회 2024 대한치과교정학회지 Vol.54 No.2

Objective: A three-dimensional-printed individual titanium plate was applied for maxillary protraction to eliminate side effects and obtain the maximum skeletal effect. This study aimed to explore the stress distribution characteristics of sutures during maxillary protraction using individual titanium plates in various directions and locations. Methods: A protraction force of 500 g per side was applied at forward and downward angles between 0° and 60° with respect to the Frankfort horizontal plane, after which the titanium plate was moved 2 and 4 mm upward and downward, respectively. Changes in sutures with multiple protraction directions and various miniplate heights were quantified to analyze their impact on the maxillofacial bone. Results: Protraction angle of 0–30° with respect to the Frankfort horizontal plane exhibited a tendency for counterclockwise rotation in the maxilla. At a 40° protraction angle, translational motion was observed in the maxilla, whereas protraction angles of 50–60° tended to induce clockwise rotation in the maxilla. Enhanced protraction efficiency at the lower edge of the pyriform aperture was associated with increased height of individual titanium plates. Conclusions: Various protraction directions are suitable for patients with different types of vertical bone surfaces. Furthermore, when the titanium plate was positioned lower, the protraction force exhibited an increase.

Experimental and numerical study on shear studs connecting steel girder and precast concrete deck

Shengfang Qiao,Huqing Liang,Jia-Bao Yan,Wanying Wang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.71 No.4

Shear studs are often used to connect steel girders and concrete deck to form a composite bridge system. The application of precast concrete deck to steel-concrete composite bridges can improve the strength of decks and reduce the shrinkage and creep effect on the long-term behavior of structures. How to ensure the connection between steel girders and concrete deck directly influences the composite behavior between steel girder and precast concrete deck as well as the behavior of the structure system. Compared with traditional multi-I girder systems, a twin-I girder composite bridge system is more simplified but may lead to additional requirements on the shear studs connecting steel girders and decks due to the larger girder spacing. Up to date, only very limited quantity of researches has been conducted regarding the behavior of shear studs on twin-I girder bridge systems. One convenient way for steel composite bridge system is to cast concrete deck in place with shear studs uniformly-distributed along the span direction. For steel composite bridge system using precast concrete deck, voids are included in the precast concrete deck segments, and they are casted with cast-in-place concrete after the concrete segments are erected. In this paper, several sets of push-out tests are conducted, which are used to investigate the heavier of shear studs within the voids in the precast concrete deck. The test data are analyzed and compared with those from finite element models. A simplified shear stud model is proposed using a beam element instead of solid elements. It is used in the finite element model analyses of the twin-I girder composite bridge system to relieve the computational efforts of the shear studs. Additionally, a parametric study is developed to find the effects of void size, void spacing, and shear stud diameter and spacing. Finally, the recommendations are given for the design of precast deck using void for twin I-girder bridge systems.