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赫尔巴特的“统觉”与陶行知的“常能” 被引量:1
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作者 涂怀京 《福建师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2007年第3期164-168,共5页
“统觉”是赫尔巴特教育思想中的一个最基本的心理学理论,“常能”是陶行知生活教育学说中的一个重要用语。在教育独创思想的构建上,“统觉”论为“常能”论呈示了一条科学的“试验”路向;在教育重要目标的达成上,“统觉”论为“常能”... “统觉”是赫尔巴特教育思想中的一个最基本的心理学理论,“常能”是陶行知生活教育学说中的一个重要用语。在教育独创思想的构建上,“统觉”论为“常能”论呈示了一条科学的“试验”路向;在教育重要目标的达成上,“统觉”论为“常能”论提供了一种有益的“组合”模式;推行素质教育,可借鉴运用“统觉”与“常能”所含的科学因素。 展开更多
关键词 赫尔巴特 陶行知 统觉 常能 应接 借鉴
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从提高质量入手,强化高职“双师”队伍建设 被引量:1
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作者 李军玲 《天津职业院校联合学报》 2015年第12期19-24,共6页
强化高职"双师"队伍建设,要突出教师的专业化修炼,要从"师智、师能、师德"等方面提升"双师"队伍的整体素质,为质量提升提供物质保证。要提升教师队伍社会需求的应接能力,用多元的方法培养"双师"。
关键词 教学管理质量 "双师"队伍 师智 师能 师德 应接能力 社会需求
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英语词汇学习策略与词汇学习效果关系的调查研究 被引量:2
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作者 高娟 《河南广播电视大学学报》 2008年第3期90-91,共2页
笔者用问卷调查、面谈和词汇测试等方式对106名英语专业学生的词汇学习策略和词汇学习效果进行了调查,分析了两者之间的关系并就词汇教学提出了一些建议。
关键词 词汇学习策略 应接性词汇 运用性受控制词汇 相关性
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Effect of welding sequence on residual stress in thin-walled octagonal pipe-plate structure 被引量:11
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作者 傅定发 周长青 +2 位作者 李灿 王冠 李落星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期657-664,共8页
A three-dimensional finite element approach based on ABAQUS code was developed to investigate the effect of welding sequence on welding residual stress distribution in a thin-walled 6061 aluminum alloy structure. To o... A three-dimensional finite element approach based on ABAQUS code was developed to investigate the effect of welding sequence on welding residual stress distribution in a thin-walled 6061 aluminum alloy structure. To obtain sound numerical results, the therrno-mechanical behaviour was simulated using a direct-coupled formulation. Nine different simulation sequences were carried out by single-pass TIG welding of an octagonal pipe-plate joint, and the distributions of longitudinal and transverse residual stresses both on the outer and inner surfaces of the pipe were analyzed. The results suggest that the final residual stresses in the weld and its vicinity are not affected by the initial residual stresses of the structure. Selecting a suitable welding sequence can reduce the final residual stress in an octagonal pipe-plate joint. 展开更多
关键词 residual stress welding sequence pipe-plate joint single-pass welding initial residual stress
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Effect of welding current on morphology and microstructure of Al alloy T-joint in double-pulsed MIG welding 被引量:10
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作者 易杰 曹淑芬 +2 位作者 李落星 郭鹏程 刘开勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3204-3211,共8页
The effect of current on the morphology of Al alloy T-joint in double-pulsed metal inert gas(DP-MIG) welding process was investigated by simulation and experiment.A three-dimensional finite element model and the DP-... The effect of current on the morphology of Al alloy T-joint in double-pulsed metal inert gas(DP-MIG) welding process was investigated by simulation and experiment.A three-dimensional finite element model and the DP-MIG heat source of double-ellipsoidal volumetric model were developed to simulate the temperature and stress fields under different welding conditions.The macro-morphology and microstructure of welding joints at the corresponding currents were observed in the experiment.The results show that the best condition is at an average current of 90 A and current difference of 40 A,when the maximum temperature is 200 °C higher than the fusion points,with the temperature difference of about 100 °C and stress change of 10 MPa between thermal pulse and thermal base.Under these conditions,Al alloy T-joint with proper fusion condition has smooth fish-scale welding appearance and finer microstructure.Furthermore,the thermal curves and stress distribution in the experiment are consistent with those in the simulation,verifying the precision of the welding simulation. 展开更多
关键词 double-pulsed MIG welding Al alloy T-joint welding current STRESS
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Contact reactive brazing of Al alloy/Cu/stainless steel joints and dissolution behaviors of interlayer 被引量:10
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作者 吴铭方 司乃潮 陈健 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1035-1039,共5页
Contact reactive brazing of 6063 Al alloy and 1Cr18Ni9Ti stainless steel was researched by using Cu as interlayer. Effect of brazing time on microstructure of the joints, as well as the dissolution behaviors of Cu int... Contact reactive brazing of 6063 Al alloy and 1Cr18Ni9Ti stainless steel was researched by using Cu as interlayer. Effect of brazing time on microstructure of the joints, as well as the dissolution behaviors of Cu interlayer was analyzed. The results show that the product of reaction zone near 1Cr18Ni9Ti is composed of Fe2Al5, FeAl3 intermetallic compound (IMC), and Cu-Al IMC; the near by area is composed of Al-Cu eutectic structure with Al (Cu) solid solution. With increasing the brazing time, the thickness of IMC layer at the interface increases, while the width of Al-Cu eutectic structure with Al(Cu) solution decreases. Calculation shows the dissolution rate of Cu interlayer is very fast. The complete dissolution time is about 0.47 s for Cu interlayer with 10 μm in thickness used in this study. 展开更多
关键词 Al alloy stainless steel contact reactive brazing MICROSTRUCTURE dissolution of interlayer
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Temperature and stress fields in electron beam welded Ti-15-3 alloy to 304 stainless steel joint with copper interlayer sheet 被引量:9
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作者 张秉刚 王廷 +2 位作者 段潇辉 陈国庆 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期398-403,共6页
Electron beam welding of Ti-15-3 alloy to 304 stainless steel (STS) using a copper filler metal was carried out. The temperature fields and stress distributions in the Ti/Fe and Ti/Cu/Fe joint during the welding pro... Electron beam welding of Ti-15-3 alloy to 304 stainless steel (STS) using a copper filler metal was carried out. The temperature fields and stress distributions in the Ti/Fe and Ti/Cu/Fe joint during the welding process were numerically simulated and experimentally measured. The results show that the rotated parabola body heat source is fit for the simulation of the electron beam welding. The temperature distribution is asymmetric along the weld center and the temperature in the titanium alloy plate is higher than that in the 304 STS plate. The thermal stress also appears to be in asymmetric distribution. The residual tensile stress mainly exists in the weld at the 304 STS side. The copper filler metal decreases the peak temperature and temperature grade in the joint as well as the residual stress. The longitudinal and lateral residual tensile strengths reduce by 66 MPa and 31 MPa, respectively. From the temperature and residual stress, it is concluded that copper is a good filler metal candidate for the electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel. 展开更多
关键词 Ti-15-3 alloy 304 stainless steel electron beam welding temperature field residual stress
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Contact Problem in Decagonal Two-Dimensional Quasicrystal 被引量:6
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作者 周旺民 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期51-55,共5页
As a new structure of solid matter quasicrystal brings profound new ideas to the traditional condensed matter physics, its elastic equations are more complicated than that of traditional crystal. A contact problem of ... As a new structure of solid matter quasicrystal brings profound new ideas to the traditional condensed matter physics, its elastic equations are more complicated than that of traditional crystal. A contact problem of decagonal two? dimensional quasicrystal material under the action of a rigid flat die is solved satisfactorily by introducing displacement function and using Fourier analysis and dual integral equations theory, and the analytical expressions of stress and displacement fields of the contact problem are achieved. The results show that if the contact displacement is a constant in the contact zone, the vertical contact stress has order -1/2 singularity on the edge of contact zone, which provides the important mechanics parameter for contact deformation of the quasicrystal. 展开更多
关键词 decagonal two-dimensional quasicrystal contact problem stress and displacement
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Simulation of a Novel Schottky Body-Contacted Structure Suppressing Floating Body Effect in Partially-Depleted SOI nMOSFET's
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作者 刘运龙 刘新宇 +2 位作者 韩郑生 海潮和 钱鹤 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第10期1019-1023,共5页
A novel Schottky body-contacted structure for partially depleted SOI nMOSFET's is presented.This structure can be realized by forming a shallow n +-p junction and two sidewall spacers in the source region,and the... A novel Schottky body-contacted structure for partially depleted SOI nMOSFET's is presented.This structure can be realized by forming a shallow n +-p junction and two sidewall spacers in the source region,and then growing a thick silicide film,which can punch through the shallow junction and make a Schottky contact to the p-type silicon.Simulation results show that the anomalous subthreshold slope and kink effects are suppressed successfully and the drain breakdown voltage is improved considerably.This method has the same device area and is completely compatible with the bulk MOSFET process. 展开更多
关键词 SOI NMOSFET floating body effect body contact
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怎样让学生掌握更多英语词汇 被引量:2
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作者 苏兰婷 《金筑大学学报(综合版)》 1999年第4期88-90,共3页
词汇、语音、语法是语言三大要素。其中词汇又是基础。毋庸置疑,词汇教学在英语教学中的地位十分重要。但是学生普遍反映要记忆大量的单词很难。我们常见学生抱着词典或单词本死记硬背,而收效甚微。我个人觉得可以从四个方面帮助学生度... 词汇、语音、语法是语言三大要素。其中词汇又是基础。毋庸置疑,词汇教学在英语教学中的地位十分重要。但是学生普遍反映要记忆大量的单词很难。我们常见学生抱着词典或单词本死记硬背,而收效甚微。我个人觉得可以从四个方面帮助学生度过词汇关,即(一)根据词汇统计学估计学生词汇量的需求;(二)快速增加词汇量的可能性;(三)词汇教学应遵循的原则;(四)词汇教学的方法,步骤。 展开更多
关键词 词汇教学 词汇量 词汇统计学 英语词汇 英语教学 语音 语言 词典 应接性词汇 词义
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Location of emergency rescue center based on SIR epidemiological model 被引量:3
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作者 胡家香 赵林度 江亿平 《Journal of Southeast University(English Edition)》 EI CAS 2007年第S1期89-93,共5页
In view of the pressure time of emergency rescue against the infectious diseases,a mathematical model to optimize the location of emergency rescue centers is proposed.The model takes full account of the spread functio... In view of the pressure time of emergency rescue against the infectious diseases,a mathematical model to optimize the location of emergency rescue centers is proposed.The model takes full account of the spread function of infectious diseases,the cycle of pulse vaccination,the distance between the demand area and the emergency rescue centers,as well as the building and maintenance cost for the emergency rescue center,and so on.At the same time,the model integrates the traditional location selection models which are the biggest cover model,the p-center model and the p-median model,and it embodies the principles of fairness and efficiency for the emergency center location.Finally,a computation of an example arising from practice provides satisfactory results. 展开更多
关键词 susceptible-infective-removed(SIR)model pulse vaccination LOCATION emergency rescue p-median model
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Direct Tunneling Effect in Metal-Semiconductor Contacts Simulated with Monte Carlo Method 被引量:2
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作者 孙雷 杜刚 +1 位作者 刘晓彦 韩汝琦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第11期1364-1368,共5页
Considering the tunneling effect and the Schottky effect,the metal semiconductor contact is simulated by using self consistent ensemble Monte Carlo method.Under different biases or at different barrier heights,the i... Considering the tunneling effect and the Schottky effect,the metal semiconductor contact is simulated by using self consistent ensemble Monte Carlo method.Under different biases or at different barrier heights,the investigation into the tunneling current indicates that the tunneling effect is of great importance under reverse biases.The Schottky barrier diode current due to Schottky effect is in agreement with the theoretical one.The barrier lowering is found a profound effect on the current transport at the metal semiconductor interface. 展开更多
关键词 Monte Carlo device simulation metal semiconductor contact direct tunneling Schottky effect
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A robot simulation system with virtual force display and feedback based on master manipulator 被引量:2
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作者 祝学云 吴涓 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期70-73,共4页
This paper describes a virtual environment, which can present dynamic force transformation during the control of objects. A 5-DOF haptic interface with the capability to generate kinesthetic effect is combined. In thi... This paper describes a virtual environment, which can present dynamic force transformation during the control of objects. A 5-DOF haptic interface with the capability to generate kinesthetic effect is combined. In this system, the operator manipulates an object in a virtual environment by using the 5-DOF master arm. When contacting with the virtual object, the contact force can be calculated and shown in the graphic interface. The contact response and deformation of the virtual object, which are usually called haptic rendering, also can be performed. The study supplies an approach to improve the operator’s immersion and can be used in many tele-robot control fields. 展开更多
关键词 virtual reality haptic display contact detection contact response
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高校网络信访的研判和处置策略
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作者 何等浩 《岭南师范学院学报》 2015年第2期55-58,共4页
由于网络具有传播迅速、影响广泛、互动性强、成本低廉等优势,网络曝光成为新媒体时代高校领域检举腐败的新方式。网络信访举报这种发展态势使得高校信访工作面临网络信访信息真伪甄别难度增加、网络信访事件向负面演化的风险增加、网... 由于网络具有传播迅速、影响广泛、互动性强、成本低廉等优势,网络曝光成为新媒体时代高校领域检举腐败的新方式。网络信访举报这种发展态势使得高校信访工作面临网络信访信息真伪甄别难度增加、网络信访事件向负面演化的风险增加、网络的信访工作应接难度增加等新问题。为此,高校应积极完善内部管理和监督预防机制,从源头上化解信访压力;健全多渠道的师生诉求反馈机制,及时解决问题和矛盾;健全网络信息公开机制,以透明的政务环境化解流言;提升网络信息处置能力,建立网络信访应接机制。 展开更多
关键词 高校 网络反腐 信访应接机制
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Direct adaptive fuzzy control based on integral-type Lyapunov function 被引量:4
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作者 张天平 朱清 +1 位作者 张惠艳 顾海军 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期92-97,共6页
A new scheme of direct adaptive fuzzy controller for a class of nonlinear systems with unknown triangular control gain structure is proposed. The design is based on the principle of sliding mode control and the approx... A new scheme of direct adaptive fuzzy controller for a class of nonlinear systems with unknown triangular control gain structure is proposed. The design is based on the principle of sliding mode control and the approximation capability of the first type fuzzy systems. By introducing integral-type Lyapunov function and adopting the adaptive compensation term of optimal approximation error, the closed-loop control system is proved to be globally stable, with tracking error converging to zero. Simulation results demonstrate the effectiveness of the approach. 展开更多
关键词 fuzzy systems fuzzy control adaptive control global stability
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Design and analysis of modular charge feeding mechanism
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作者 刘海刚 王刚 +2 位作者 熊胜 刘鹏飞 张孝忠 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期240-246,共7页
Aiming at the turning motion's disadvantages,including the instability of charge magazine caused by polygon effect and the disability of synchronously pushing modular charge of the current pushing mechanism,a new typ... Aiming at the turning motion's disadvantages,including the instability of charge magazine caused by polygon effect and the disability of synchronously pushing modular charge of the current pushing mechanism,a new type of charge feeding mechanism is designed.It can not only select modular charge rapidly and steadily,but also push a certain amount of modular charge into the tray which is used to receive the charge synchronously.The selection and push principles of feeding mechanism are introduced,and a three-dimensional model is established.ADAMS is applied to simulation analysis of the feeding mechanism.The results show that the feeding mechanism can push the modular charge into the reception tray rapidly and steadily,which provides a theoretical basis for the practical design. 展开更多
关键词 modular charge polygon effect feeding mechanism ADAMS reception tray
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Multi-Defect Generation Behavior in Ultra Thin Oxide Under DT Stresses
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作者 霍宗亮 毛凌锋 +1 位作者 谭长华 许铭真 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第2期127-132,共6页
The saturation behavior of stress current is studied.The three types of precursor sites for trap generation are also introduced by fitting method based on first order rate equation.A further investigation by statistic... The saturation behavior of stress current is studied.The three types of precursor sites for trap generation are also introduced by fitting method based on first order rate equation.A further investigation by statistics experiments shows that there are definite relationships among time constant of trap generation,the time to breakdown,and stress voltage.It also means that the time constant of trap generation can be used to predict oxide lifetime.This method is faster for TDDB study compared with usual breakdown experiments. 展开更多
关键词 DEFECT MOS structure time dependence dielectric breakdown
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MODEL REFERENCE ADAPTIVE CONTROL BASED ON NONLINEAR COMPENSATION FOR TURBOFAN ENGINE 被引量:4
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作者 潘慕绚 黄金泉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期215-221,共7页
The design of a turbofan rotor speed control system, using model reference adaptive control(MRAC) method with input and output measurements, is discussed for the purpose of practical application. The nonlinear compe... The design of a turbofan rotor speed control system, using model reference adaptive control(MRAC) method with input and output measurements, is discussed for the purpose of practical application. The nonlinear compensator based on functional link neural network is used to deal with the engine nonlinearity and the hardware-in-loop simulation is also developed. The results show that the nonlinear MRAC controller has the adequate performance of compensating and adapting nonlinearity arising from the change of engine state or working environment. Such feature demonstrates potential practical applications of MRAC for aeroengine control system. 展开更多
关键词 turbofan engin model reference adaptive control(MRAC) functional link neural network (FLNN) hardware-in-loop(HIL) simulation
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中国先进文化与当代书法艺术精神
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作者 陈云金 《书画世界》 2004年第7期12-15,共4页
本文首先通过对中国先进文化优越性的认识以及对中国书法受文化影响的简要回顾,得出结论:当代书法应与先进文化结合起来,主动应接先进文化,才能积极健康地发展。在此基础上,进一步阐述了书法要应接先进文化就必须把握『三种精神』:即民... 本文首先通过对中国先进文化优越性的认识以及对中国书法受文化影响的简要回顾,得出结论:当代书法应与先进文化结合起来,主动应接先进文化,才能积极健康地发展。在此基础上,进一步阐述了书法要应接先进文化就必须把握『三种精神』:即民族精神、科学精神和大众化精神。 展开更多
关键词 先进文化 当代书法 民族精神 科学精神 大众化精神 应接
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Detection of Neisseria Gonorrhoeae from Urine with Ligase Chain Reaction
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作者 曹经江 郑和义 胡维 《Chinese Journal of Sexually Transmitted Infections》 2003年第2期33-36,68,共6页
Objective: To evaluate the value of ligase chainreaction(LCR) in the diagnosis of diplococcusgonorrhoeae in urine. Methods: LCR detection of the urine for Neisseriagonorrhoeae and bacteria culture of discharge was per... Objective: To evaluate the value of ligase chainreaction(LCR) in the diagnosis of diplococcusgonorrhoeae in urine. Methods: LCR detection of the urine for Neisseriagonorrhoeae and bacteria culture of discharge was per-formed simultaneously to 276 patients with urethritisor cervicitis seeking treatment in sex transmitted dis-eases (STDs) outpatient clinic. For specimens withdiscordant results, polymerase chain reaction wasconducted. The purpose was to detect the respectivesensitivity and specificity of bacteria culture and LCR. Results: 24 of 276(8.7%) patients had positive LCRresults and 21 of 276(7.6%) were positive for culture.5 specimens had discordant results from LCR andbacteria culture. The sensitivity and specificity of LCRin the diagnosis of gonorrhoeae were 92.3% and100% respectively. Conclusion: This study showed that LCR had ahigher sensitivity and specificity for the diagnosis ofgonorrhoeae from urine. 展开更多
关键词 neisseria gonorrhocae ligatse chain reaction URINE
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