http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Investigating the origin of third harmonic generation from diabolo optical antennas
Shi, Liping,Andrade, José,R. C.,Kim, Hyunwoong,Han, Seunghwoi,Nicolas, Rana,Franz, Dominik,Boutu, Willem,Heidenblut, Torsten,Segerink, Frans B.,Bastiaens, Bert,Merdji, Hamed,Kim, Seung-Woo,Morgn American Institute of Physics 2017 Applied Physics Letters Vol.111 No.17
Effects of weight on bit on torsional stick-slip vibration of oilwell drill string
Liping Tang,Xiaohua Zhu,Xudong Qian,Changshuai Shi 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.10
The stick-slip phenomenon is a type of dysfunction detrimental to the drilling operation. Field application shows that stick-slip phenomenon is inclined to appear when using a large Weight on bit (WOB). In this paper, effects of the WOB on the stick-slip vibration are investigated. Based on a lumped torsional pendulum model of the drilling system, equation of motion of the drill bit is obtained. By using parameters commonly used in field applications, the bit dynamics are analyzed and the stick-slip vibrations are discussed. During the stick-slip motions, the negative damping effect occurs in the transition from the stick phase to the slip phase. With the increasing WOB, the bit behavior may change from the stable motion to the stick-slip vibration once the WOB reaches the critical value. In case of stickslip vibration, the phase trajectory ultimately converges to a limit cycle which represents periodical bit motion. With increases in the WOB, the limit cycle enlarges. For cases without stick-slip vibrations, the drill bit vibrates damply and finally converges to a state of uniform motion. The results presented in this paper can be applied to interpret some of the field phenomena related to WOB.
Analysis of mechanical behavior and hysteresis heat generating mechanism of PDM motor
Changshuai Shi,Xiaohua Zhu,Juan Deng,Liping Tang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.3
Positive displacement motor (PDM), which is prone to high temperature fatigue failure, can be weakened in its application in deep and superdeep well. In order to study the forced state, deformation regularity and thermal hysteresis of PDM motor, the paper established the three-dimensional thermal-mechanical coupled Finite element model (FEM). Based on the theoretical research, experimental study and numerical simulation, the study found that the displacement of stator lining shows a sinusoidal variation under internal pressure, when adapting the general form of sine function to fitting inner contour line deformation function. Then the paper analyzed the hysteresis heat generating mechanism of the motor, learning that hysteresis thermogenous of stator lining occurs due to the viscoelastic of rubber material and cyclic loading of stator lining. A heartburn happens gradually in the center of the thickest part of the stator lining as temperature increases, which means work efficiency and service life of PDM will be decreased when used in deep or superdeep well. In this paper, we established a theory equation for the choice of interference fit and motor linetype optimization design, showing hysteresis heat generating analyzing model and method are reasonable enough to significantly improve PDM’s structure and help better use PDM in deep and surdeep well.
Nan Shi,Hongwei Xu,Kaiyuan Guo,Chunyu Kang,Wei Zhang,Yingying Zhang,Liping Zhang,Jianxin Tan 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.8
Partitioning of microbial transglutaminase (MTG) from Amycolatopsis sp. in the polyethylene glycol (PEG)/salt-based ATPS was investigated for the first time. The key parameters such as the molecular weight of PEG (PEG 600-6000), the type and concentration of phase-forming salt (ammonium sulfate or phosphates), the pH of system (pH 5.0-8.5), and the concentration of neutral salt (0-6% NaCl, w/w) were determined. The partition coefficient of the enzyme was not linear with PEG molecular weight; PEG1000 gave better yield than others. The concentration of PEG1000, ammonium sulfate and NaCl, and the system pH showed effects with different extents on specific activity (SA) and yield of the enzyme. In the ATPS of 26% w/w PEG 1000 and 19% w/w ammonium sulfate in the presence of 5% w/w NaCl and at pH 6.0, MTG was partitioned into the PEG-rich phase with a maximum yield of 86.51% and SA was increased to 0.83. The results of SDS-PAGE showed the MTG produced by the test strain differed from the enzymes reported before. Thus, this study proves that ATPS can be used as a preliminary step for partial purification of MTG from Amycolatopsis sp. fermentation broth.
Advanced Stability Analysis of the Tunnels in Jointed Rock Mass Based on TSP and DEM
Hongyun Fan,Liping Li,Hongliang Liu,Shaoshuai Shi,Jie Hu,Shen Zhou 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.4
The discrete element method (DEM) can analyze the large deformation and large displacement of rock mass effectively, and it is widely used in underground engineering, slope engineering and other fields. However, due to the low accuracy of rock mass structural surface information acquisition, the application of discrete element method in the analysis of jointed rock mass stability is still deviated. In this paper, combined with the advantages of the tunnel seismic prediction (TSP) in obtaining discontinuous geological interface information and the discrete element method in the calculation and analysis of jointed rock mass stability, this paper proposes an advanced analysis method for jointed rock mass stability based on TSP and DEM. Compared to the traditional methods, the analysis results of the jointed rock mass stability are more reliable. Firstly, relying on the advanced detection system – Tunnel Seismic Prediction 203Plus, the unstructured rock mass structure information of the tunnel is obtained, and the spatial attitude of the discontinuous geological interface is further determined. Secondly, based on the Fish programming language, the non-continuous geological interface information can be expressed in the discrete unit software – 3D Distinct Element Code (3DEC). In this way, the excavation calculation model of the tunnels in jointed rock mass can be constructed. Finally, based on the DEM, the excavation of the tunnels in jointed rock mass can be simulated, analyze the stability of surrounding rock during the tunnel excavation process, and realize the stability analysis of surrounding rock stability of jointed rock mass. Based on the Huangjiazhuang Tunnel Project, this paper uses the above method to carry out on-site application. The results show that the location of the dangerous block is predicted to be consistent with the actual exposure of the tunnel surrounding rock based on TSP and DEM, which verify the accuracy and feasibility of this method, and the research results have practical guiding significance for the safe construction of the tunnels in jointed rock mass.
Chenyang Qi,Liping Zou,Suxia Wang,Xing Mao,Yuan Hu,Jiaoyu Shi,Zhigang Zhang,Huijuan Wu 대한암학회 2022 Cancer Research and Treatment Vol.54 No.1
Purpose The role of vacuolar protein sorting 34 (Vps34), an indispensable protein required for cell vesicular trafficking, in the biological behavior of hepatocellular carcinoma (HCC) has yet to be studied. Materials and Methods In the present study, the expression of Vps34 in HCC and the effect of Vps34 on HCC cell invasion was detected both in vivo and in vitro. Furthermore, by modulating the RILP and Rab11, which regulate juxtanuclear lysosome aggregation and recycling endosome respectively, the underlying mechanism was investigated. Results Vps34 was significantly decreased in HCC and negatively correlated with the HCC invasiveness both in vivo and in vitro. Moreover, Vps34 could promote lysosomal juxtanuclear accumulation, reduce the invasive ability of HCC cells via the Rab7-RILP pathway. In addition, the deficiency of Vps34 in HCC cells affected the endosome-lysosome system, resulting in enhanced Rab11 mediated endocytic recycling of cell surface receptor and increased invasion of HCC cells. Conclusion Our study reveals that Vps34 acts as an invasion suppressor in HCC cells, and more importantly, the endosome-lysosome trafficking regulated by Vps34 has the potential to become a target pathway in HCC treatment.
Chunheng Zhou,Zongping Chen,Sheldon Q. Shi,Liping Cai 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.27 No.6
This study proposed a new type of concrete column that was confined with both steel angles and spiral hoops, named angle-steel and spiral confined concrete (ASCC) column. A total of 22 ASCC stub columns were tested under axial compression to investigate their behavior. For a comparison, three angle-steel reinforced concrete (ARC) stub columns were also tested. The test results indicated that ASCC column had a superior mechanical performance. The strength, ductility and energy absorption were considerably increased due to the improvement of confinement from spiral hoops. The confinement behavior and failure mechanism of ASCC column were investigated by the analysis of failure mode, load-deformation curve and sectionstrain distribution. Parametric studies were carried out to examine the influences of different parameters on the axial compression behavior of ASCC columns. A calculation approach was developed to predict the ultimate load carrying capacity of ASCC columns under axial compression. It was validated that the predicted results were in well agreement with the experimental results.
Collapse risk evaluation method on Bayesian network prediction model and engineering application
WANG, Jing,LI, Shucai,LI, Liping,SHI, Shaoshuai,XU, Zhenhao,LIN, Peng Techno-Press 2017 Advances in computational design Vol.2 No.2
Collapse was one of the typical common geological hazards during the construction of tunnels. The risk assessment of collapse was an effective way to ensure the safety of tunnels. We established a prediction model of collapse based on Bayesian Network. 76 large or medium collapses in China were analyzed. The variable set and range of the model were determined according to the statistics. A collapse prediction software was developed and its veracity was also evaluated. At last the software was used to predict tunnel collapses. It effectively evaded the disaster. Establishing the platform can be subsequent perfect. The platform can also be applied to the risk assessment of other tunnel engineering.