The Analysis of City-geology Problems in the Growth of Cites

( Jian Jun Song ),( Long Yi Shao ),( Cheng Ling Chu ),( Jian Ping Ye ),( Fan Yu Ye ) 대한지질공학회 2007 국제학술발표회 논문집 Vol.2007 No.-

A Rapid Online Calculation Method of Three-dimensional Plastic Deformation in Strip Rolling

Jian Shao,Chihuan Yao,Chaochao Chen,Wenquan Sun,Anrui He 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

Three-dimensional strip plastic deformation model is a key part of shape setup model in hot rolling. The numerical efficiency, accuracy and stability of the method are the main factors that may restrict its online application. Considering the theoretical limitations of existing models, basic equations include equilibrium equations with the effect of shear stress, constitutive equations based on incremental theory, and lubricated friction with the respective coefficients of friction at longitudinal and transverse direction. After normalization of parameters and the asymptotic analysis, the strip plastic deformation model is established, and solved by finite volume method and BICGSTAB algorithm to get the transverse distribution of rolling force of each stand. Compared to the finite element model established by ANSYS software, the new model has reliable results and a short computation time of 31 milliseconds, which show its feasibility of online application.

Novel Auto-regressive Measurement of Diamond Tool Wear in Ultra-precision Raster Milling

Shao-Jian Zhang,Suet To,Chi-Fai Cheung,Jian-Jun Du 한국정밀공학회 2012 International Journal of Precision Engineering and Vol. No.

In this paper, a new auto-regressive algorithm is proposed to reconstruct 3D topographic surface for diamond tool wear, using its in-process image. First, based on digital image processing technique, tool wear lands are separated from a tool wear image captured by a CCD camera under a 100X optical system; Second, a traverse search method of arc translation is put forward to eliminate feigned wear lands, and a least square polynomial method is adopted to fit inner- and outer-contours of the wear lands, self-adaptively filtering noises and connecting the discontinuous wear lands; Finally, the auto-regressive calibration method is developed to reconstruct its 3D topographic surface. The wear land is extracted self-adaptively, and the wear area, maximal wear width, average wear width and worn volume can be determined automatically by the algorithm. The reconstructed 3D topography of the tool wear land can be identified, based on the tool wear image captured by SEM. The result indicates that the method is capable of reconstructing 3D topography of the tool wear land and provides a possibility for in-process 3D-wear measurement in ultra-precision raster milling (UPRM) and the algorithm reliability is validated finally. And the influence of tool wear on surface roughness is discussed.

Research on the Inter-harmonics Equivalent Impedance of Series Hybrid Active Power Filter

Jian-gong, Zhang,Jian-ben, Liu,Shao-jun, Dai,Qiao-fu, Chen,Jun-jia, He The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.5

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

Experimental study on cold-formed lipped channel stub columns reinforced by steel bars or steel strips

Jian-Feng Chen,Ming-Qi Chen,Yong-Kang Shen,Jian-Hua Shao,Xin-Xin Yang 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.40 No.3

In this paper, the axial compressive properties of cold-formed steel lipped channel stub columns strengthened by rebars or steel strips are experimentally studied. The experiment included two sections. A kind of columns with local buckling is reinforced longitudinally by steel strips at the web. The other is the columns with distorted buckling, which is reinforced longitudinally by steel bars at the curling edge. The failure mode, deformation characteristics, ultimate bearing capacity and load displacement curve of the specimen are obtained through the experiment. On the basis of the experiment, the calculation results of theoretical axial bearing capacity of cold-formed steel lipped channel stub columns in Chinese, North American and Australian code are compared and analyzed. Research indicates: First, the cold-formed steel lipped channel stub columns strengthened by steel bars or steel strips can effectively improve the compressive bearing capacity of the specimen. Secondly, when the initial stress ratio of specimen is less than 0.3, the reinforcement effect is ideal. Thirdly, the three standards don’t stipulate the calculation of theoretical bearing capacity of the specimen strengthened after loading, so there is a large deviation between the theoretical calculation value and the test value.

Research on the Comprehensive Control Strategy of Over-welding Based on Decoupling- Design for Tandem Cold Mills

Jian Shao,Wenquan Sun,Anrui He 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.3

The strategies of the welding seam dynamic passing control and feasible loose edge rolling technology are put forward. In the process of cold mill welding, by dynamic regulation roll-gap, bending force and stand speed. The control strategy of reducing tensions between stands and strip edge is achieved. At the same time, the decoupling control strategy of plate shape and thickness can reduce the influence of roll-gap on plate shape and of bending force and stand speed on the steel thickness. Simulation analysis and practical application show that the technology effectively reduces the occurrence of steel strip fracture of tandem cold mill units.

miR-9 Modulates Osteosarcoma Cell Growth by Targeting the GCIP Tumor Suppressor

Zhu, Shao-Wen,Li, Jian-Peng,Ma, Xin-Long,Ma, Jian-Xiong,Yang, Yang,Chen, Yang,Liu, Wei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Osteosarcoma is the most common primary bone tumor in humans, especially in childhood. However, the genetic etiology for its pathogenesis remains elusive. It is known that microRNAs (miRNAs) are involved in the development of tumor progression. Here we show that microRNA-9 (miR-9) is a potential oncogene upregulated in osteosarcoma cells. Knockdown of miR-9 in osteosarcoma resulted in suppressed colony formation and cell proliferation. Further study identified GCIP, a Grap2 and cyclin D interacting protein, as a direct target of miR-9. In addition, GCIP overexpression activated retinoblastoma 1 (Rb) and suppressed E2F transcriptional target expression in osteosarcoma cells. Moreover, GCIP depletion reversed miR-9 knockdown induced colony formation and cell proliferation suppression. In sum, these results highlight the importance of miR-9 as an oncogene in regulating the proliferation of osteosarcoma by directly targeting GCIP and may provide new insights into the pathogenesis of osteosarcoma.

Research on the Inter-harmonics Equivalent Impedance of Series Hybrid Active Power Filter

Zhang Jian-gong,Liu Jian-ben,Dai Shao-jun,Chen Qiao-fu,He Jun-jia 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.5

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

A Voltage Stability Analysis Method of Multi-infeed HVDC Power Systems

Shao, Yao,Tang, Yong,Zhang, Jian,Li, Baiqing The Korean Institute of Electrical Engineers 2014 The Journal of International Council on Electrical Vol.4 No.1

According to the Chinese power network planning, the risk of voltage instability at the receiving-end AC power system will be increased significantly, where there will be more HVDC systems feeding into a same AC grid in the future. At present, the effective voltage stability analysis methods of multi-infeed DC (MIDC) system are few, the most widely used method with most research results is the multi-infeed short-circuit ratio (MISCR) index at home and abroad. The deficiency of MISCR index is pointed out. The relationship between multi-infeed interaction factor (MIIF) and the voltage stability of the receiving-end AC system is discussed. Then a new method joint MIIF and MISCR indexes to evaluate the voltage stability of MIDC system is put forward. Finally, simulation tests and analysis results of a large actual grid prove the feasibility and good performance of the proposed new method.

Identification of Halohydrin Dehalogenase Mutants that Resist COBE Inhibition

Shao-Yun Chen,Xiu-Juan He,Jian-ping Wu,Gang Xu,Li-Rong Yang 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.1

The biocatalytic cascade conversion of ethyl4-chloroacetoacetate (COBE) to ethyl (R)-4-cyano-3-hydroxybutyrate ((R)-HN) for the preparation of atorvastatinrepresents significant economic and environmental benefits,and is catalyzed by alcohol dehydrogenase and halohydrindehalogenase (HHDH). However, as the activity of HHDHis inhibited by COBE, the cascade reaction is an inefficientone-pot reaction. In this study, substrate inhibition kineticsanalysis was performed and the inhibition by COBE wasfound to be competitive reversible inhibition. Molecularsimulation analysis was used to determine the inhibitionmechanism by COBE. The results showed that COBEbound to the active center of HHDH via the formation ofhydrogen bonds with the OH groups of S132 and Y145. Site saturation mutagenesis of residues around the activesite and at the entrance of the access tunnel was performed,and two target mutant residues were identified, F136 andW249. Small focused mutagenesis on these two residueswas performed and the F136V/W249F mutant wassuccessfully found to relieve the activity inhibition ofHHDH by COBE. The half inhibiting concentration ofmutant F136V/W249F was found to be 20-fold higher thanwild-type HHDH. The efficiency of the multi-enzymaticone-pot system for the synthesis of (R)-HN from COBEusing mutant F136V/W249F was improved significantly.