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| 1 | Algorithm for Smooth S-curve Feedrate Profiling Generation显示文摘The algorithms for feedrate profile generation,such as linear and S-curve profiles,have been widely used in machinery controllers,and these algorithms can greatly improve the smoothness of motion.However,most of the algorithms lead to the discontinuous acceleration/deceleration and jerk,or high jerk levels,which is very harmful to machine tool or robot in most occasions. This paper presents a smooth S-curve feedrate profiling generation algorithm that produces continuous feedrate,acceleration,and jerk profiles.Smooth jerk is obtained by imposing limits on the first and second time derivatives of acceleration,resulting in trapezoidal jerk profiles along the tool path.The discretization of smooth S-curve feedrate is realized with a novel approach that improves the efficiency without calculating the deceleration point in each sampled time.To ensure that the interpolation time is a multiple of the value of sampled time,the feedrate,acceleration,jerk,and jerk derivative are recalculated.Meantime,to improve the efficiency,the interpolation steps of all regions are computed before interpolation.According to the distance of trajectory,the smooth S-curve acceleration and decelerations are divided into three blocks:normal block,short block type-Ⅰ,and short block type-Ⅱ.Finally feedrate discretization of short block type-Ⅰand type-Ⅱis obtained with considering the efficiency.The proposed generation algorithm is tested in machining a part on a five axis milling machine,which is controlled with the CNC system for newly developed high-speed machine tools.The test result shows that the smooth S-curve approach has the smoother feedrate,acceleration,deceleration,and jerk profiles than S-curve.The proposed algorithm ensures the automated machinery motion smoothness,and improves the quality and efficiency of the automated machinery motion planning. | CHEN Youdong WEI Hongxing SUN Kai LIU Miao WANG Tianmiao | 2011 | Chinese Journal of Mechanical Engineering2011，24，2： | 13 |
| 2 | Layer-by-layer deposition of bioactive layers on magnesium alloy stent materials to improve corrosion resistance and biocompatibility显示文摘Magnesium alloy is considered as one of the ideal cardiovascular stent materials owing to its good mechanical properties and biodegradability.However,the in vivo rapid degradation rate and the insufficient biocompatibility restrict its clinical applications.In this study,the magnesium alloy(AZ31B)was modified by combining the surface chemical treatment and in-situ self-assembly of 16-phosphonyl-hexadecanoic acid,followed by the immobilization of chitosan-functionalized graphene oxide(GOCS).Heparin(Hep)and GOCS were alternatively immobilized on the GOCS-modified surface through layer by layer(LBL)to construct the GOCS/Hep bioactive multilayer coating,and the corrosion resistance and biocompatibility were extensively explored.The results showed that the GOCS/Hep bioactive multilayer coating can endow magnesium alloys with an excellent in vitro corrosion resistance.The GOCS/Hep multilayer coating can significantly reduce the hemolysis rate and the platelet adhesion and activation,resulting in an excellent blood compatibility.In addition,the multilayer coating can not only enhance the adhesion and proliferation of the endothelial cells,but also promote the vascular endothelial growth factor(VEGF)and nitric oxide(NO)expression of the attached endothelial cells on the surfaces.Therefore,the method of the present study can be used to simultaneously control the corrosion resistance and improve the biocompatibility of the magnesium alloys,which is expected to promote the application of magnesium alloys in biomaterials or medical devices,especially cardiovascular stent. | Fan Gao Youdong Hu Guicai Li Sen Liu Li Quan Zhongmei Yang Yanchun Wei Changjiang Pan | 2020 | Bioactive Materials2020，5，3： | 12 |
| 3 | CFD Investigation of the Influence of Volute Geometrical Variations on Hydrodynamic Characteristics of Circulator Pump显示文摘Improper design of volute geometry can be the main cause that leads to unsteady pressure pulsation and radial force in pumps. Therefore, it is important to understand the influence of volute geometrical parameters on hydrodynamic characteristics of pump and the mechanism. However, the existing studies are limited to investigate the influence of only one or two volute geometrical parameters each time, and a systematic study of the influence of the combinations of different volute geometrical parameters on the pump's hydrodynamic characteristics is missing. In this paper, a study on the understanding of the influence of volute geometrical variations on hydrodynamic characteristics of a high speed circulator pump by using computational fluid dynamics(CFD) technology is presented. Five main volute geometrical parameters D_3, A_8, a_0, j_0 and Rt are selected and 25 different volute configurations are generated by using design of experiments(DOE) method. The 3D unsteady flow numerical simulations, which are based on the SST k-w turbulence model and sliding mesh technique provided by CFX, are executed on the 25 different volute configurations. The hydraulic performance, pressure pulsation and unsteady radial force inside the pump at design condition are obtained and analyzed. It has been found that volute geometrical parameters D_3 and A_8 are major influence factors on hydrodynamic characteristics of the pump, while a_0, j_0 and Rt are minor influence factors. The minimum contribution from both D_3 and A_8 is 58% on head, and maximum contribution from both D_3 and A_8 is 90% on pressure pulsation. Regarding the pressure pulsation intensity, two peaks can be found. One is in the tongue area and the other is in the diffusor area. The contributions are around 60% from tongue and 25% from diffusor, respectively. The amplitude of pressure pulsation has a quadratic polynomial functional relationship with respect to D_3/D_2 and A_8/A_(10), and fluctuating level of radial force has a quadratic polynomial functional relationship with respect to D_3/D_2. While for the other volute parameters a_0, j_0 and Rt, no special function has been found related to pressure pulsation and radial force. The presented work could be a useful guideline in engineering practice when designing a circulator pump with low hydrodynamic force. | WU Denghao YUAN Shouqi REN Yun MU Jiegang YANG Youdong LIU Jian | 2016 | Chinese Journal of Mechanical Engineering2016，29，2： | 11 |
| 4 | Bile acids evoke placental inflammation by activating Gpbar1/NF-κB pathway in intrahepatic cholestasis of pregnancy显示文摘Intrahepatic cholestasis of pregnancy(ICP)is a cholestatic disorder with potentially deleterious consequences for fetuses.Although a clear correlation between the elevated levels of maternal serum bile acids and deficient fetal outcome has been established in clinical practice,the underlying mechanisms remain elusive.Herein,we report that bile acids induce NF-κB pathway activation via G protein-coupled bile acid receptor 1(Gpbar1),with consequent upregulation of inflammatory genes in trophoblasts,leading to aberrant leukocyte infiltration and inflammation in placenta.Ursodeoxycholic acid(UDCA),a drug used clinically to treat ICP,competes with other bile acids for binding with Gpbar1 and thus inhibits bile acid-induced inflammatory response in trophoblasts and improves fetal survival in pregnant rats with obstructive cholestasis.Notably,inhibition of NF-κB by andrographolide is more effective than UDCA in benefiting placentas and fetuses.Thus,anti-inflammation therapy targeting Gpbar1/NF-κB pathway could be effective in suppressing bile acid-induced inflammation and alleviating ICP-associated fetal disorders. | YouHua Zhang YouDong Pan ChangDong Lin YaJuan Zheng Hao Sun HaiLong Zhang JunLei Wang MengYa Yuan Tao Duan QiaoLing Du JianFeng Chen | 2016 | Journal of Molecular Cell Biology2016，8，6： | 8 |
| 5 | Three-dimensional Tool Radius Compensation for Multi-axis Peripheral Milling显示文摘Few function about 3D tool radius compensation is applied to generating executable motion control commands in the existing computer numerical control (CNC) systems. Once the tool radius is changed, especially in the case of tool size changing with tool wear in machining, a new NC program has to be recreated. A generic 3D tool radius compensation method for multi-axis peripheral milling in CNC systems is presented. The offset path is calculated by offsetting the tool path along the direction of the offset vector with a given distance. The offset vector is perpendicular to both the tangent vector of the tool path and the orientation vector of the tool axis relative to the workpiece. The orientation vector equations of the tool axis relative to the workpiece are obtained through homogeneous coordinate transformation matrix and forward kinematics of generalized kinematics model of multi-axis machine tools. To avoid cutting into the corner formed by the two adjacent tool paths, the coordinates of offset path at the intersection point have been calculated according to the transition type that is determined by the angle between the two tool path tangent vectors at the corner. Through the verification by the solid cutting simulation software VERICUTwith different tool radiuses on a table-tilting type five-axis machine tool, and by the real machining experiment of machining a soup spoon on a five-axis machine tool with the developed CNC system, the effectiveness of the proposed 3D tool radius compensation method is confirmed. The proposed compensation method can be suitable for all kinds of threeto five-axis machine tools as a general form. | CHEN Youdong WANG Tianmiao | 2013 | Chinese Journal of Mechanical Engineering2013，26，3： | 5 |
| 6 | A novel aminated polymeric adsorbent for removing refractory dissolved organic matter from landfill leachate treatment plant显示文摘Refractory dissolved organic matter (DOM) from landfill leachate treatment plant was with high dissolved organic carbon (DOC) content. An aminated polymeric adsorbent NDA-8 with tertiary amino groups and sufficient mesopore was synthesized, which exhibited high adsorption capacity to the DOM (raw water after coagulation). Resin NDA-8 performed better in the uptake of the DOM than resin DAX-8 and A100. Electrostatic attraction was considered as the decisive interaction between the adsorbent and adsorbate. Special attention was paid to the correlation between porous structure and adsorption capacity. The mesopore of NDA-8 played a crucial role during uptake of the DOM. In general, resin in chloride form performed a higher removal rate of DOC. According to the column adsorption test, total adsorption capacity of NDA-8 was calculated to 52.28 mg DOC/mL wet resin. 0.2 mol/L sodium hydroxide solution could regenerate the adsorbent efficiently. | ZHANG Long, LI Aimin, WANG Jinnan, LU Yufei, ZHOU Youdong State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China. | 2009 | Journal of Environmental Sciences2009，21，8： | 5 |
| 7 | Modeling of grout crack of rockbolt grouted system显示文摘This paper presents a numerical study on the pullout behavior of the rockbolt grouted system. Among the complicated failure modes of the rockbolt grouted system, the crack of the grout is concerned here. A trilinear cohesive zone model(CZM) is used to simulate the interfacial behavior of rockbolt–grout interface;and a plastic damaged model is adopted for the grout materials. The feasibility of the numerical method is verified by comparing the calculated results with the test observations. The numerical results indicate that two types of cracks of the grout materials can be identified as the inclined crack and the horizontal crack. The inclined crack forms firstly and then the horizontal crack. Both cracks can reduce the interfacial shear stress and thus reduce the load transfer efficiency. Further analysis indicates that the crack of the gout material can induce the obvious drops of load capacity, which is not a safe failure mode. This study leads to a better understanding of the mechanism for rockbolt grouted system. | Zhu Changxing Chang Xu Men Youdong Luo Xulin | 2015 | International Journal of Mining Science and Technology2015，25，1： | 2 |
| 8 | Reliable modeling and optimization for chemical engineering applications: Interval analysis approach显示文摘 | LIN YOUDONG GWALTNEY C R STADTHERR M A | 2006 | Reliable Computing2006，12，6： | 1 |
| 9 | The Existence of Positive Solution for a Fourth-Order Three-Point Boundary Value Problem 显示文摘 | ZHANG Yanhong ZENG Youdong | 2005 | Journal of Fuzhou University (Natural Science)2005，33，1： | 1 |
| 10 | Geometric continuity between adjacent Bezier patches and their constructions显示文摘 | Ye Xiuzhi Liang Youdong Nowacki H | 1996 | Computer-Aided Geometric Design1996，13，9： | 1 |
| 11 | CAM sys- tem for filament winding on elbows 显示文摘 | LI Haisheng LIANG Youdong BAO Hujun | 2005 | Journal of Mate- rials Processing Technology2005，161，3： | 1 |
| 12 | Problems about geometric continuity for curves and surfaces 显示文摘 | LIANG Youdong | 1990 | Chinese Annals of Mathematics1990，11，6： | 1 |
| 13 | AN EXTENSION OF CLARIAUT EQUATION AND ITS APPLICATION | LIANG YOUDONG ZOU ZHENQIANG AND WANG GUOZHAO | 1997 | Applied Mathematics(A Journal of Chinese Universities)1997，12，1： | 1 |
| 14 | BAX and CDKN1A polymorphisms correlated with clinical outcomes of gastric cancer patients treated with postoperative chemotherapy显示文摘 | Xiaoting Wang Youdong Lin Fenghua Lan Yinghao Yu Xuenong Ouyang Wei Liu Feilai Xie Xuzhou Wang Qiaojia Huang | 2014 | Medical Oncology2014，，： | 1 |
| 15 | CAM system for filament winding machine on elbows 显示文摘 | Li Haisheng Liang Youdong Bao Hujun | 2005 | Journal of Materials Processing Technology2005，，161： | 1 |
| 16 | Algorithm for Smooth S-curve Feedrate Profiling Generation显示文摘 | CHEN Youdong WEI Hongxing SUN Kai LIU Miao and WANG Tianmiao School of Mechanical Engineering and Au-tomation Beihang University Beijing 100191 China | | 0，，02： | 1 |
| 17 | Covalent organic nanosheets with large lateral size and high aspect ratio synthesized by Langmuir-Blodgett method显示文摘Two-dimensional(2 D) materials have attracted increasing attentions recently due to their unique physical and chemical properties. We herein report the synthesis of four chemically stable 2 D covalent organic nanosheets(CONs) with large lateral sizes(up to 200 mm) and high aspect ratios(>20 000) at the air-water interface through the Langmuir-Blodgett method. These CONs exhibit good crystallinity proved by high resolution transmission electron microscopy(HRTEM) and selected area electron diffraction(SAED). In addition, the hydrophobicity of these CONs can be systematically adjusted by the introduction of various functional groups, making them suitable as functional coating and membrane materials. | Youdong Cheng Sai Kishore Ravi Yuxiang Wang Jifang Tao Yuandong Gu Swee Ching Tan Dan Zhao | 2018 | Chinese Chemical Letters2018，29，6： | 1 |
| 18 | Effect of digital problem-based learning cases on student learning outcomes in ophthalmology courses显示文摘 | Jun Kong Xiaoyan Li Youdong Wang | | 0，，09： | 1 |
| 19 | Comparison between the time-integrated spectrum and the peak time spectrum of gamma-ray bursts and possible implications显示文摘The mono-frequency peak luminosity and the corresponding photon energy of the time-integrated(Ls p,Es p)and peak time(Lt p,Et p)νfνspectra were derived for a sample of 38 redshift-known Fermi GRBs by fitting the spectra with the Band function.It was found that Et pis generally consistent with Es p,and Lt pis averagely three times larger than Ls p.The slope of the Lt p-Et prelation was consistent with that of the Ls p-Es prelation.The photon indices in the peak time spectrum,particularly,the index of the low energy end was,were statistically larger than that in the time-integrated spectrum.These results indicate that Ls pand Es pare dominated by Lt pand Et p,respectively.The difference of the spectral indices between the time-integrated and peak time spectra may be because of the overlap effect of a series of time-resolved spectra within a GRB.Our simulations,which were based on the observed spectral evolution and correlation between the energy flux and the peak energy within individual GRBs support our speculations.The Lt p-Et prelation may be less contaminated by the overlap effect,and it would may be an intrinsic feature of radiation physics. | LYU Fen WANG YuanZhu LIANG YunFeng LIN TingTing HU YouDong LIANG EnWei | 2015 | Science China(Physics,Mechanics & Astronomy)2015，58，3： | 1 |
| 20 | Rosuvastatin, Identified From a Zebrafish Chemical Genetic Screen for Antiangiogenic Compounds, Suppresses the Growth of Prostate Cancer显示文摘 | Chunyang Wang Weiyang Tao Youdong Wang Jennifer Bikow Bingxin Lu Armand Keating Subodh Verma Thomas G. Parker Ruifa Han Xiao-Yan Wen | 2010 | European Urology2010，，3： | 1 |
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