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CO2点阵激光联合卤米松和NB-UVB治疗稳定期非节段型白癜风疗效观察 预览 被引量:1
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作者 唐娟 应航宇 《中国美容医学》 CAS 2019年第1期64-67,共4页
目的:探究CO2点阵激光联合卤米松和窄谱中波紫外线(Narrowband ultraviolet-B,NB-UVB)治疗稳定期非节段性白癜风的临床效果。方法:纳入2012年6月-2017年12月于笔者医院对传统治疗无效的稳定期非节段型白癜风患者80例,选择患者3处相似的... 目的:探究CO2点阵激光联合卤米松和窄谱中波紫外线(Narrowband ultraviolet-B,NB-UVB)治疗稳定期非节段性白癜风的临床效果。方法:纳入2012年6月-2017年12月于笔者医院对传统治疗无效的稳定期非节段型白癜风患者80例,选择患者3处相似的皮损分别给予不同的治疗方案,采用自身对照的研究方案。所有患者3处皮损分别给予3种不同的治疗方案:方案1:采用剥脱性CO2点阵激光联合卤米松和NB-UVB治疗;方案2:仅接受NB-UVB治疗;方案3:接受非剥脱性CO2点阵激光联合卤米松和NB-UVB治疗。观察患者接受不同治疗方案治疗后3个月、6个月的临床效果。结果:治疗3个月、6个月后,采用剥脱性CO2点阵激光联合卤米松和NB-UVB治疗的患者临床效果显著优于仅接受NB-UVB治疗的患者;采用非剥脱性点阵激光联合卤米松和NB-UVB治疗的患者与仅接受NB-UVB治疗的患者治疗后3个月临床效果无显著差异;随着治疗时间的延长,各种治疗方案治疗效果均显著提高。结论:剥脱性CO2点阵激光联合卤米松和NB-UVB治疗稳定期非节段型白癜风患者临床疗效可靠,较非剥脱性点阵激光联合治疗临床效果更优。 展开更多
关键词 白癜风 CO2点阵激光 NB-UVB 卤米松 联合治疗
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING PICK-UP MECHANISM TRANSMISSION ratio Non-uniform continuous TRANSMISSION COMBINED NON-CIRCULAR gear TRANSMISSION Optimization design
Numerical modeling of lock-exchange gravity/turbidity currents by a high-order upwinding combined compact difference scheme 预览
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作者 Liang Zhao Ching-Hao Yu Zhiguo He 《国际泥沙研究:英文版》 SCIE 2019年第3期240-250,共11页
This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including t... This study presents two-dimensional direct numerical simulations for sediment-laden current with higher density propagating forward through a lighter ambient water.The incompressible NavierStokes equations including the buoyancy force for the density difference between the light and heavy fluids are solved by a finite difference scheme based on a structured mesh.The concentration transport equations are used to explore such rich transport phenomena as gravity and turbidity currents.Within the framework of an Upwinding Combined Compact finite Difference(UCCD)scheme,rigorous determination of weighting coefficients underlies the modified equation analysis and the minimization of the numerical modified wavenumber.This sixth-order UCCD scheme is implemented in a four-point grid stencil to approximate advection and diffusion terms in the concentration transport equations and the first-order derivative terms in the Navier-Stokes equations,which can greatly enhance convective stability and increase dispersive accuracy at the same time.The initial discontinuous concentration field is smoothed by solving a newly proposed Heaviside function to prevent numerical instabilities and unreasonable concentration values.A two-step projection method is then applied to obtain the velocity field.The numerical algorithm shows a satisfying ability to capture the generation,development,and dissipation of the Kelvin-Helmholz instabilities and turbulent billows at the interface between the current and the ambient fluid.The simulation results also are compared with the data in published literatures and good agreements are found to prove that the present numerical model can well reproduce the propagation,particle deposition,and mixing processes of lock-exchange gravity and turbidity currents. 展开更多
关键词 GRAVITY CURRENT TURBIDITY CURRENT Depth-resolving mathematical model INCOMPRESSIBLE Navier-Stokes equations Upwinding COMBINED Compact Difference(UCCD) scheme
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Technological innovations of electric arc furnace bottom-blowing in China
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作者 Guang-sheng Wei Rong Zhu +2 位作者 Yun Wang Xue-tao Wu Kai Dong 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第9期909-916,共8页
Nowadays, in China, the bottom-blowing technique plays an important role in accelerating the molten bath stirring and promoting the metallurgical reactions in electric arc furnace (EAF) steelmaking. The innovations of... Nowadays, in China, the bottom-blowing technique plays an important role in accelerating the molten bath stirring and promoting the metallurgical reactions in electric arc furnace (EAF) steelmaking. The innovations of bottom-blowing technologies in EAF steelmaking were reviewed. The optimized bottom-blowing arrangement in EAF based on the furnace structure and the position of electrodes was introduced, and the fluid flow characteristics of EAF molten bath with bottomblowing were analyzed. Furthermore, bottom-blowing CO2 in EAF can facilitate the carbon-oxygen reaction reaching equilibrium and decrease the content of nitrogen in molten steel due to its special metallurgical properties. Pulsating bottom-blowing in EAF can effectively improve the molten bath stirring through the action of the unsteady bottom blowing gas streams, which could make the fluid flow field more disorderly than the steady bottom-blowing. And submerged O2 injection with CO2 in EAF can noticeably strengthen the EAF molten bath stirring, increase the production efficiency and improve the molten steel quality. 展开更多
关键词 Electric arc furnace Bottom-blowing CO2 Pulsating bottom-blowing EAF combined BLOWING technology Submerged O2 injection with CO2
Application of Combined Prediction Model in Predicting Total Water Consumption in Ningxia 预览
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作者 Yongliang WANG Jiongli CHEN Lian TANG 《亚洲农业研究:英文版》 2019年第3期45-47,共3页
The gray GM( 1,1) prediction model and Logistic equation gray prediction model were established separately,and then the combined prediction model was established. Taking the water consumption in Ningxia Hui Autonomous... The gray GM( 1,1) prediction model and Logistic equation gray prediction model were established separately,and then the combined prediction model was established. Taking the water consumption in Ningxia Hui Autonomous Region from 2006 to 2012 as modeling data,the total water consumption of the whole region of Ningxia in 2018-2020 was analyzed and predicted. The results show that the accuracy of the three prediction models meets the accuracy requirements,but the gray GM( 1,1) and combined prediction models better conform to the actual situation and have better applicability. 展开更多
关键词 GM (1 1) PREDICTION LOGISTIC equation GRAY PREDICT Combined PREDICTION Water CONSUMPTION
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Mechanical Properties of Reactive Powder Concretes Produced Using Pumice Powder
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作者 Abdurrezzak BAKIS Ercan ISIK +1 位作者 Alev Akilli EL MustafaüLKER 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第2期353-360,共8页
We examined the applicability of the pumice aggregate on the concrete formed by considering the reactive powder concrete mixture ratios, for the rigid superstructure concrete road pavement and building construction. T... We examined the applicability of the pumice aggregate on the concrete formed by considering the reactive powder concrete mixture ratios, for the rigid superstructure concrete road pavement and building construction. The natural pumice aggregate in fibrous and non-fibrous concrete samples was used in the production of concrete by fracturing in 0.1-0.6 mm dimensions in rotor mill. The concreted formed in this way is named after the pumice powder concrete(PPC). The PPC samples produced were taken 7 days as 20 ℃ standard water cure, 28 days as 20 ℃ standard cure and 9 different types of combined cures. The combined cures were applied different temperatures in different durations. PPC samples were subjected to some pressure and flexural tests at the end of the standard water and combined cures. The highest compressive and flexural strengths of PPC samples were obtained after the combined cures: 3 days in 20 ℃ as standard water curing + 2 days in 180 ℃ in drying-oven. The highest compressive strength of PPC samples without any fiber was found to be 47.27 MPa, as for the highest flexural strength, it is found to be 5.23 MPa, in the end of the study. The highest compressive strength of fibrous PPC samples was 51.12 MPa, while flexural strength was 6.57 MPa. 展开更多
关键词 reactive POWDER CONCRETE (RPC) PUMICE POWDER CONCRETE (PPC) combined CURE compressive STRENGTH FLEXURAL STRENGTH
Magnetoelastic combined resonance and stability analysis of a ferromagnetic circular plate in alternating magnetic field 预览
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作者 Yuda HU Bingbing MA 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第7期925-942,共18页
The nonlinear combined resonance problem of a ferromagnetic circular plate in a transverse alternating magnetic field is investigated. On the basis of the deformation potential energy, the strain potential energy, and... The nonlinear combined resonance problem of a ferromagnetic circular plate in a transverse alternating magnetic field is investigated. On the basis of the deformation potential energy, the strain potential energy, and the kinetic energy of the circular plate, the Hamilton principle is used to induce the magnetoelastic coupling transverse vibration dynamical equation of the ferromagnetic circular plate. Based on the basic electromagnetic theory, the expressions of the magnet force and the Lorenz force of the circular plate are presented. A displacement function satisfying clamped-edge combined with the Galerkin method is used to derive the Duffing vibration differential equation of the circular plate. The amplitude-frequency response equations of the system under various combined resonance forms are obtained by means of the multi-scale method, and the stability of the steady-state solutions is analyzed according to the Lyapunov theory. Through examples, the amplitude-frequency characteristic curves with different parameters, the amplitude of resonance varying with magnetic field intensity and excitation force, and the time-course response diagram, phase diagram, Poincar′e diagram of the system vibration are plotted, respectively. The effects of different parameters on the amplitude and stability of the system are discussed. The results show that the electromagnetic parameters have a significant effect on the multi-valued attribute and stability of the resonance solutions, and the system may exhibit complex nonlinear dynamical behavior including multi-period and quasi-periodic motion. 展开更多
关键词 MAGNETOELASTICITY FERROMAGNETIC circular plate COMBINED RESONANCE multi- scale method ALTERNATING magnetic field
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Experimental Study on Dynamic Mechanical Properties of Sprayed Concrete-Surrounding Rock Combined Body 预览
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作者 Dongming Guo Pengyang Yan +2 位作者 Longfei Fan Yingshi Zhang Xiaoye Wang 《北京理工大学学报:英文版》 EI CAS 2019年第2期278-285,共8页
To investigate the dynamic response problem of the double medium formed by the adherence of sprayed concrete and surrounding rock in the tunnel,a split Hopkinson pressure bar of 75 mm in diameter was adopted at the ag... To investigate the dynamic response problem of the double medium formed by the adherence of sprayed concrete and surrounding rock in the tunnel,a split Hopkinson pressure bar of 75 mm in diameter was adopted at the ages of 3,7 and 10 d.Experimental results showed that dynamic compressive strength and dynamic increase factors(DIF)of the combined bodies increase with the strain rate.With the growth of strain rate,the critical strain of the combined bodies first increases,then deceases.Furthermore,the combined bodies of 3 d reveal the plastic property and brittle property for 7 d and 10 d when the strain rate is over 80/s.The failure characteristic of the sprayed concrete changes from tearing strain damage to crushing damage as the growth of strain rate,and the failure characteristic of rock presents the tensile failure mode as demonstrated by the scanning electron microscope(SEM). 展开更多
关键词 SPRAYED concrete-surrounding rock COMBINED BODY DYNAMIC compressive strength DYNAMIC increase factors critical strain failure modes
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子宫颈癌合并糖尿病围术期的治疗探究 预览
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作者 朱越 刘立鹏 《糖尿病新世界》 2019年第9期39-40,共2页
目的主要就子宫颈癌合并糖尿病围术期治疗效果进行探究,并为其他医疗工作者该类型疾病临床治疗提供一定参考。方法通过随机选择法从该院2016年1月-2018年6月这一时间段中所收治子宫颈癌合并糖尿病患者中选取100例作为研究对象。之后利... 目的主要就子宫颈癌合并糖尿病围术期治疗效果进行探究,并为其他医疗工作者该类型疾病临床治疗提供一定参考。方法通过随机选择法从该院2016年1月-2018年6月这一时间段中所收治子宫颈癌合并糖尿病患者中选取100例作为研究对象。之后利用数表法将他们平均分成实验组与对照组,每组50例患者,其中前者临床治疗中采取的是在围术期糖尿病常规联合腹腔镜手术方式;而后者临床治疗上则采取腹腔镜手术方式。为了判断实验组与对照组两种临床治疗效果哪个更优,该文主要通过手术成功率、平均住院时间以及糖尿病并发症率这4项指标来对比。结果治疗完成后经数据统计分析可知,实验组患者在手术成功率、平均住院时间、血糖控制以及糖尿病并发症率四项指标上均明显好于对照组,并且差异有统计学意义(P<0.05)。结论针对子宫颈癌合并糖尿病患者围术期中除了要做糖尿病常规治疗以外还应联合腹腔镜手术进行治疗,这样一来不但可以有效地提升病人手术成功几率,同时对于确保他们生存率也大有裨益。 展开更多
关键词 子宫颈癌 合并 糖尿病 围术期 腹腔镜手术 治疗 效果
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1035工作面风巷沿空掘巷围岩控制技术 预览
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作者 黄胜 《山东煤炭科技》 2019年第10期8-10,共3页
针对袁店一井煤矿1035工作面风巷地质构造复杂、断层发育状况,对沿空掘巷矿压特征进行研究,合理确定煤柱宽度并采取针对性的支护方案,取得了良好的围岩控制效果,保证了施工进度与施工安全。
关键词 沿空 窄煤柱 联合 支护
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Drag Characteristics Prediction for Wet Multi-Disk Brakes 预览
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作者 Tianhong Luo Zhongtao Li Fuying Li 《北京理工大学学报:英文版》 EI CAS 2019年第3期549-560,共12页
To improve the characteristics of wet multi-disc brakes (WMDBs), the WMDBs of the drive axles of mining trucks were studied. A model was established to predict the phenomenon of drag characteristics during wet brake n... To improve the characteristics of wet multi-disc brakes (WMDBs), the WMDBs of the drive axles of mining trucks were studied. A model was established to predict the phenomenon of drag characteristics during wet brake non-engagement by considering the combined effect of surface grooves, film shrinkage, and laminar Navier-Stokes (N-S) equations. The model was used to study drag torque and temperature variation of the wet brakes for different volume flows, dynamic viscosities, and friction pair clearances. The simulation results indicated that the peak torque decreased when the clearance of the friction pair increased. Additionally, the peak torque increased when the volume flow increased and when the cooling liquid dynamic viscosity increased. The model was more accurate than a traditional forecasting system when considering the role of surface grooves and oil film shrinkage in actual working conditions. 展开更多
关键词 WET BRAKE drag TORQUE combined effects MULTI-PARAMETER PREDICTION system
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盐酸纳布啡复合丙泊酚在成人无痛胃镜检查术中的应用 预览
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作者 汪云散 洪娜 +2 位作者 查白薇 陈云飞 陈兰仁 《中国临床保健杂志》 CAS 2019年第2期258-261,共4页
目的探讨盐酸纳布啡复合丙泊酚在成人无痛胃镜检查中的麻醉效果和安全性。方法选取中科大附属第一医院西区18~65岁之间拟行无痛胃镜检查患者120例。采用随机数字表法分为3组,即低、高剂量纳布啡复合丙泊酚麻醉组(N1组,40例;N2组,40例)... 目的探讨盐酸纳布啡复合丙泊酚在成人无痛胃镜检查中的麻醉效果和安全性。方法选取中科大附属第一医院西区18~65岁之间拟行无痛胃镜检查患者120例。采用随机数字表法分为3组,即低、高剂量纳布啡复合丙泊酚麻醉组(N1组,40例;N2组,40例)及芬太尼复合丙泊酚麻醉组(F组,40例)。N1、N2组患者静脉分别注射纳布啡0. 05 mg/kg、0. 10 mg/kg,F组患者静脉注射芬太尼1. 0 ug/kg,三组都复合丙泊酚1. 5mg/kg。三组患者均根据术中出现吞咽反射、呛咳、体动等静脉追加丙泊酚注射液以维持一定的麻醉深度。记录三组患者麻醉诱导前(T0)、睫毛反射消失时(T1)、胃镜刚入食管时(T2)、苏醒时(T3)的平均动脉压(MAP)、心率(HR)、血氧饱和度(SpO2),以及三组患者胃镜检查时间、苏醒时间、丙泊酚用量、围术期并发症发生率。结果N1、N2组患者术中低氧血症(T1-T3)的发生率低于F组,差异有统计学意义(P <0. 05);组内比较,三组术中(T1-T3) MAP、HR皆较T0下降,差异有统计学意义;N1、N2组患者苏醒时间显著缩短,差异有统计学意义(P <0. 05);N1、N2组患者围手术期并发症发生率显著低于F组,差异有统计学意义(P <0. 05)。N1丙泊酚用量高于N2组,差异有统计学意义。三组胃镜检查时间差异无统计学意义。结论盐酸纳布啡复合丙泊酚用于成人无痛胃镜检查术具有良好的麻醉效果和安全性。 展开更多
关键词 胃镜检查 麻醉药 联用 纳布啡 二异丙酚
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复杂条件下软岩煤层支护工艺研究 预览
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作者 王亮 《山东煤炭科技》 2019年第10期25-27,共3页
为了保证软岩煤层巷道掘进施工安全,提高巷道掘进效率及顶板稳定性,避免顶板事故发生,对施工巷道过断层顶板破碎应力区提出了“超前注浆+超前撞楔支护+工字钢棚”等联合支护措施,加快了巷道掘进速度,提高了破碎区域顶板稳定性,取得了显... 为了保证软岩煤层巷道掘进施工安全,提高巷道掘进效率及顶板稳定性,避免顶板事故发生,对施工巷道过断层顶板破碎应力区提出了“超前注浆+超前撞楔支护+工字钢棚”等联合支护措施,加快了巷道掘进速度,提高了破碎区域顶板稳定性,取得了显著成效。 展开更多
关键词 巷道 破碎 联合 支护
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双摄像机模组的组合式标定和校正方法 预览
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作者 杨风开 杨红亮 程素霞 《计算机工程与科学》 CSCD 北大核心 2019年第2期302-307,共6页
提出了双摄像机模组的组合式标定和校正方法,能够将传统的标定和校正2道工序合并为1道工序,不需要借助于外部测量设备,仅利用双摄像机同时对目标模板拍摄的1幅图像,即可实现双摄像机模组的标定和校正。先基于交比不变性计算摄像机的径... 提出了双摄像机模组的组合式标定和校正方法,能够将传统的标定和校正2道工序合并为1道工序,不需要借助于外部测量设备,仅利用双摄像机同时对目标模板拍摄的1幅图像,即可实现双摄像机模组的标定和校正。先基于交比不变性计算摄像机的径向畸变系数,将摄像机畸变成像模型转换为线性模型,利用线性模型分别对2个摄像机进行标定;然后计算2个摄像机之间的位姿偏移参数,调节右摄像机位姿,进行双摄像机之间的位姿校正;最后标定2个摄像机之间的位姿参数。实际应用结果表明,所提出的双摄像机模组校正和标定方法,校正和标定精度高,缩短了工艺时间,提高了工艺效率,能够满足双摄像机模组封装生产工艺的要求。 展开更多
关键词 双摄像机模组 位姿 组合式 标定 校正
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The preliminary study on the combined application model of serum miRNAs in the diagnosis of pneumoconiosis
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作者 刘义涛 《中国医学文摘:内科学分册(英文版)》 2019年第2期75-76,共2页
Objective To explore the role of serum microRNA(miRNAs) levels in the detection of pneumoconiosis,and to establish a combined application model of multiple serums miRNAs for pneumoconiosis diagnosis. Methods152 cases ... Objective To explore the role of serum microRNA(miRNAs) levels in the detection of pneumoconiosis,and to establish a combined application model of multiple serums miRNAs for pneumoconiosis diagnosis. Methods152 cases were selected in case group and control group respectively. 展开更多
关键词 MIRNAS the COMBINED application model SERUM MIRNAS
数车刀具刀尖半径补偿与G71指令结合编程加工应用策略 预览
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作者 刘才志 《数字技术与应用》 2019年第6期14-15,共2页
车刀刀尖半径补偿功能是数控车削编程、加工中的重点、难点,G71指令是数控车削外圆中应用最为普及的一个指令,正确、有效的将以上两个指令结合在一起进行编程和加工,对提高粗精车外圆的效率、加工质量有着极其重要的意义。本文就刀具刀... 车刀刀尖半径补偿功能是数控车削编程、加工中的重点、难点,G71指令是数控车削外圆中应用最为普及的一个指令,正确、有效的将以上两个指令结合在一起进行编程和加工,对提高粗精车外圆的效率、加工质量有着极其重要的意义。本文就刀具刀尖半径补偿在G71功能编程中的具体应用进行分析,以提高编程效率和加工质量。 展开更多
关键词 刀具半径补偿 G71 结合 编程 加工
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基于功率内分流的复合式双流传动系统及其换挡控制研究 预览
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作者 侯郭顺 孙保群 +1 位作者 陈杰峰 杨瑞恒 《合肥工业大学学报:自然科学版》 CAS 北大核心 2019年第5期608-616,682共10页
文章基于内分流式液压机械双流传动系统(hydro-mechanical transmission,HMT)的基本特性,借鉴双离合变速器传动原理,提出了一种复合式液压机械双流传动系统(combined hydro-mechanical transmission,CHMT)方案,介绍了CHMT系统 2种换挡... 文章基于内分流式液压机械双流传动系统(hydro-mechanical transmission,HMT)的基本特性,借鉴双离合变速器传动原理,提出了一种复合式液压机械双流传动系统(combined hydro-mechanical transmission,CHMT)方案,介绍了CHMT系统 2种换挡控制方法,重点分析了由低挡HMT换入高挡HMT工况的换挡控制过程;在综合考虑液压泵和液压马达效率时,以某拖拉机作为应用平台,利用Matlab/Simulink建立了CHMT系统模型。通过仿真分析,验证了该换挡控制方案的可行性;并在此基础上,提出和验证了通过对液压元件及控制过程的优化能够进一步改善换挡品质的方案,更好地满足了负载车辆的换挡要求。 展开更多
关键词 内分流 复合式 液压机械双流传动系统(HMT) 液压效率 换挡控制 仿真 优化
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一种组合式伪随机数发生器的构造
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作者 韩露露 杨波 +1 位作者 来齐齐 曹艳艳 《小型微型计算机系统》 CSCD 北大核心 2019年第3期573-578,共6页
伪随机数发生器(Pseudorandom Number Generator,PRNG)是密码学应用系统的一个重要组成部分.本文利用线性同余发生器(Linear Congruential Generator,LCG)、流密码算法RC4和密码学Hash函数,构造了一种基于软件实现的组合式伪随机数发生... 伪随机数发生器(Pseudorandom Number Generator,PRNG)是密码学应用系统的一个重要组成部分.本文利用线性同余发生器(Linear Congruential Generator,LCG)、流密码算法RC4和密码学Hash函数,构造了一种基于软件实现的组合式伪随机数发生器.该伪随机数发生器可以快速生成伪随机数列并且从理论上证明了产生的数列具备不可预测性.同时,采用美国国家标准和技术研究院(National Institute of Standard Technology,NIST)发行的随机性测试包对该新构造的伪随机数发生器所产生的序列进行统计测试.实验结果显示,该新构造的伪随机数发生器产生的序列能够很好地通过各项测试,可以应用于信息安全领域. 展开更多
关键词 组合式 伪随机数发生器 LCG RC4 HASH函数 不可预测性
Application of a green coagulant with PACl in efficient purification of turbid water and its mechanism study
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作者 Yuxiang Xue Zhouzhou Liu +1 位作者 Aimin Li Hu Yang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第7期168-180,共13页
The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chlo... The applications of natural polymeric flocculants due to their green feature has been recently received much more attention. In this work, the combined usages of a cationic starch-based coagulant and polyaluminum chloride(PACl) were extensively evaluated for various addition sequences in the coagulation of both raw(surface water from the Jiuxiang River) and synthetic turbid water(two kaolin suspensions with different initial turbidities).Two typical cationic starch-based coagulants with different structures(St-G and St-E) were tried. In comparison to St-G, St-E and PACl used individually as well as St-G and St-E dosed after PACl, the combination of the starch-based coagulants fed before PACl showed higher turbidity removal efficiency, which featured not only less optimal doses of both inorganic and organic coagulants but also lower residual turbidity. On the basis of a detailed analysis of the particle size and its distribution in solution supernatants before and after coagulation by two starch-based coagulants and PACl, polymeric coagulants preferentially coagulate the small-sized colloids due to their distinct long-chain structures, but PACl preferentially coagulates the medium-sized ones. Thus, the medium-sized particles that were previously formed by the starch-based coagulants would be collectively and effectively removed by the subsequent addition of PACl. The addition sequence of the inorganic and organic coagulants in their combined usage is an important factor for improvement of the turbidity removal efficiency in practice. 展开更多
关键词 Cationic starch-based green COAGULANTS POLYALUMINUM chloride Combined COAGULATION SYNERGISTIC COAGULATION effects SYNERGISTIC mechanisms
Identification of key genes and pathways for Alzheimer's disease via combined analysis of genome-wide expression profiling in the hippocampus
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作者 Mengsi Wu Kechi Fang +3 位作者 Weixiao Wang Wei Lin Liyuan Guo Jing Wang 《生物物理学报:英文版》 CSCD 2019年第2期98-109,共12页
In this study, combined analysis of expression profiling in the hippocampus of 76 patients with Alzheimer's disease (AD) and 40 healthy controls was performed. The effects of covariates (including age, gender, pos... In this study, combined analysis of expression profiling in the hippocampus of 76 patients with Alzheimer's disease (AD) and 40 healthy controls was performed. The effects of covariates (including age, gender, postmortem interval, and batch effect) were controlled, and differentially expressed genes (DEGs) were identified using a linear mixed-effects model. To explore the biological processes, functional pathway enrichment and protein-protein interaction (PPI) network analyses were performed on the DEGs. The extended genes w让h PPI to the DEGs were obtained. Finally, the DEGs and the extended genes were ranked using the convergent functional genomics method. Eighty DEGs with q < 0.1, in eluding 67 downregulated and 13 upregulated genes, were identified. In the pathway enrichment analysis, the 80 DEGs were significantly enriched in one Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, GABAergic synapses, and 22 Gene Ontology terms. These genes were mainly involved in neuron, synaptic signaling and transmission, and vesicle metabolism. These processes are all linked to the pathological features of AD, dem on strating that the GABAergic system, neurons, and synaptic function might be affected in AD. In the PPI network, 180 extended genes were obtained, and the hub gene occupied in the most central position was CDC42. After prioritizing the candidate genes, 12 genes, including five DEGs (ITGB5, RPH3A, GNAS, THY1, and SEPT6) and seven extended genes (JUN, GDl1, GN Al2, NEK6, UBE2D3, CDC42EP4, and ERCC3), were found highly relevant to the progression of AD and recog nized as promising biomarkers for its early diag no sis. 展开更多
关键词 Alzheimer's disease Combined analysis HIPPOCAMPUS Gene expression DIFFERENTIALLY EXPRESSED genes MICROARRAY
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