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电视新闻节目的话题参与性探析
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作者 黄勤 《东南传播》 2007年第2期105-106,共2页
新闻话题讨论,是近几年来电视节目在体裁创新方面取得较大突破的一种形式,它主要是围绕观众感兴趣的、或广泛关注的物质生活、精神生活内容点题,选择受众自发参与进行播报,从而实现电视观众广泛参与的一种固定栏目.
关键词 电视新闻 目的话 物质生活 生活内容 话题讨论 电视观众 电视节目 自发参 选择 兴趣 栏目 创新 播报
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掘客的传播特征及其价值实现 被引量:2
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作者 胡忠青 《东南传播》 2008年第2期56-57,共2页
掘客,音译于英文dig,有挖掘、挖得、掘出等意思。它最早起源于美国,来源于现在已位列全美第24位的大众英文网站www.digg.com。
关键词 传播特征 英文 网站 内容创建 自发参 用户 网友 起源 美国 交流 服务 分类
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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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Modelling and Solution of a Ablation-Transpiration Cooling Control Systems
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作者 郭宝珠 郝涌 《Journal of Beijing Institute of Technology》 EI CAS 1994年第2期114-121,共8页
A controlled model of thermal shield of ablation with trapspiration cooling is develoed. The existence and uniqueness of the classical solution can be obtained by Friedman and Jiang's methods. The positivity of th... A controlled model of thermal shield of ablation with trapspiration cooling is develoed. The existence and uniqueness of the classical solution can be obtained by Friedman and Jiang's methods. The positivity of the solution is proved and the conditions for the coolant flux under which the abladtion process will complete in finite time are also determined. Finally, we show the existence of critical coolant flux beyond which the ablation material begin melting. 展开更多
关键词 ablation evaporative cooling dristributed parameter system the boundary
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Analysis Expression of Rate Equation for Vertical Cavity Lasers 被引量:1
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作者 PANWei CHENJian-guo 《Semiconductor Photonics and Technology》 CAS 2000年第1期40-47,共8页
An analysis solution of rate equation is derived for vertical cavity surface-emitting lasers. Based on the enhanced spontaneous emission caused by VCSELs and influence of nonradiative recombination, the relation betwe... An analysis solution of rate equation is derived for vertical cavity surface-emitting lasers. Based on the enhanced spontaneous emission caused by VCSELs and influence of nonradiative recombination, the relation between output properties and structural parameters of multi-quantum wells (MQWs) is obtained. It was found that the characteristic curve of a“thresholdless”laser is strongly nonradiative depopulation-dependent. When the nonradiative depopulation is no zero, the light-current characteristic is not linearly even for an ideal closed microcavity. The light output is increased by the enhanced well number and by the reduced width. In particular, a lower threshold current density for MQW structure in the short cavity is realized by us, meanwhile the sharpness of the variation depends on spontaneous emission factor. 展开更多
关键词 Rate equation Spontaneous emission factor Structural parameters of MQWs VCSELS
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A New Approach to Calculate Parameters of Induction Generator with Double Windings
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作者 刘长红 姚若萍 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期186-189,共4页
The accuracy prediction for the performance of an induction generator depends much on the parameters of the equivalent circuit. This paper presented a new way for calculating these parameters of induction generator wi... The accuracy prediction for the performance of an induction generator depends much on the parameters of the equivalent circuit. This paper presented a new way for calculating these parameters of induction generator with double windings. The method is based on 2D time-dependent magnetic field coupled with electric circuit. An application example of a 12-phase self-excited induction generator (SEIG) was provided to demonstrate the effectiveness of the presented approach. Some of the calculated results show good coincidence with the experiment values. 展开更多
关键词 equivalent parameters self-excited induction generators double windings FEM
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Crystallization Kinetics of Batch Spontaneous Nucleation of Potassium Nitrate
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作者 伍川 黄培 +3 位作者 黄德春 杨红群 徐南平 时钧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期589-595,共7页
The batch cooling crystallization initiated from spontaneous nucleation for aqueous solution of potassium nitrate was studied. The concentration and transmittance data were acquired on line throughout the operation.Ba... The batch cooling crystallization initiated from spontaneous nucleation for aqueous solution of potassium nitrate was studied. The concentration and transmittance data were acquired on line throughout the operation.Based on solute mass transfer in both liquid and solid phases, a kinetic model was deduced by assuming that the late period of primary nucleation resembles the initial period of the secondary nucleation. Nucleation and crystal growth stages were identified. Kinetic parameters were estimated piecewise from online experimental data and compared with those in literature. The estimated kinetic parameters for stages without apparent primary nucleation agreed well with those in literature. Further, a simulated concentration curve was also drawn from the estimated kinetic parameters and it matched well with that in experiment. 展开更多
关键词 potassium nitrate batch spontaneous crystallization mathematical modeling parameter estimation NUCLEATION crystal growth
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A bottom-up method for module-based product platform development through mapping,clustering and matching analysis
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作者 张萌 李国喜 +2 位作者 曹建平 龚京忠 吴宝中 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期623-635,共13页
Designing product platform could be an effective and efficient solution for manufacturing firms. Product platforms enable firms to provide increased product variety for the marketplace with as little variety between p... Designing product platform could be an effective and efficient solution for manufacturing firms. Product platforms enable firms to provide increased product variety for the marketplace with as little variety between products as possible. Developed consumer products and modules within a firm can further be investigated to find out the possibility of product platform creation. A bottom-up method is proposed for module-based product platform through mapping, clustering and matching analysis. The framework and the parametric model of the method are presented, which consist of three steps:(1) mapping parameters from existing product families to functional modules,(2) clustering the modules within existing module families based on their parameters so as to generate module clusters, and selecting the satisfactory module clusters based on commonality, and(3) matching the parameters of the module clusters to the functional modules in order to capture platform elements. In addition, the parameter matching criterion and mismatching treatment are put forward to ensure the effectiveness of the platform process, while standardization and serialization of the platform element are presented. A design case of the belt conveyor is studied to demonstrate the feasibility of the proposed method. 展开更多
关键词 product platform development bottom-up method MAPPING CLUSTERING MATCHING
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Optimization of Parameters for Fermentative Production of Virgin Coconut Oil by Lactobacillus fermentum NDRI 141
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作者 Neela Satheesh N. B. L. Prasad 《Journal of Food Science and Engineering》 2012年第1期44-50,共7页
Commercially, many methods are adopted for the production of the Virgin Coconut Oil (VCO). Nowadays, natural fermentation is widely employed to produce VCO in wet processing. But the problem in natural fermentation ... Commercially, many methods are adopted for the production of the Virgin Coconut Oil (VCO). Nowadays, natural fermentation is widely employed to produce VCO in wet processing. But the problem in natural fermentation process has much contamination, due to surplus micro organisms present in natural environment, which leads to the poor quality of VCO. To overcome this, usage of probiotic organism like Lactobacillus fermentum is more beneficial for the fermentative production of VCO. Fermentation studies were conducted scientifically in computer controlled bioreactor to determine the effect of pH, temperature, inoculum concentration, oxygen requirement and incubation time on the yield of VCO. Yield efficiency of VCO in each parameter was determined. The pH of 5± 0.1, temperature at 45 ± 0.1 ~C, inoculum concentration of 2%, fermentation end time of 48 hrs and microaerophilic conditions are the most suitable parameters for the superior production of VCO. 展开更多
关键词 Virgin coconut oil (VCO) coconut milk Lactobacillusfermentum.
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脉冲光场作用下啁啾双光子量子特性研究
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作者 李百宏 炎正馨 +1 位作者 张涛 李永放 《光学学报》 EI CAS CSCD 北大核心 2012年第4期256-261,共6页
基于量子理论和非线性光学,研究了脉冲光场作用啁啾准相位匹配非线性晶体的第Ⅱ类自发参变下转换过程中,脉冲宽度和啁啾系数对产生的纠缠双光子特性及Hong-Ou-Mandel(HOM)量子干涉结果的影响。结果表明,啁啾系数一定时,随着脉冲宽度的增... 基于量子理论和非线性光学,研究了脉冲光场作用啁啾准相位匹配非线性晶体的第Ⅱ类自发参变下转换过程中,脉冲宽度和啁啾系数对产生的纠缠双光子特性及Hong-Ou-Mandel(HOM)量子干涉结果的影响。结果表明,啁啾系数一定时,随着脉冲宽度的增加,双光子谱的不可区分性降低,HOM量子干涉可见度下降。当脉冲宽度一定时,随着啁啾系数的增加使双光子谱带宽增加,HOM量子干涉陷落变窄,双光子谱的不可区分性增强,从而提高了相干精度和干涉可见度。理论上得到了超宽带的双光子谱和对应超窄的HOM量子干涉图。 展开更多
关键词 量子光学 啁啾双光子 第Ⅱ类自发参变下转换 Hong-Ou-Mandel量子干涉 脉冲
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飘香生态园
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作者 袁清明(制作) 石朝虹(摄影) 《中国烹饪》 2009年第9期106-107,共2页
捞拌自发参 主料:自发美国干参30克。
关键词 捞拌自发参 珍果茶 主料 制作方法
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Experimental one-step deterministic polarization entanglement purification 被引量:3
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作者 Cen-Xiao Huang Xiao-Min Hu +4 位作者 Bi-Heng Liu Lan Zhou Yu-Bo Sheng Chuan-Feng Li Guang-Can Guo 《Science Bulletin》 SCIE EI CSCD 2022年第6期593-597,M0003,共6页
Entanglement purification is to distill high-quality entangled states from low-quality entangled states.It is a key step in quantum repeaters,determines the efficiency and communication rates of quantum communication ... Entanglement purification is to distill high-quality entangled states from low-quality entangled states.It is a key step in quantum repeaters,determines the efficiency and communication rates of quantum communication protocols,and is hence of central importance in long-distance communications and quantum networks.In this work,we report the first experimental demonstration of deterministic entanglement purification using polarization and spatial mode hyperentanglement.After purification,the fidelity of polarization entanglement arises from 0.268±0.002 to 0.989±0.001.Assisted with robust spatial mode entanglement,the total purification efficiency can be estimated as 10^(9) times that of the entanglement purification protocols using two copies of entangled states when one uses the spontaneous parametric down-conversion sources.Our work may have the potential to be implemented as a part of full repeater protocols. 展开更多
关键词 Quantum entanglement Hyperentanglement Quantum communication Deterministic entanglement purification Quantum repeater
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Experimentally testing Bell's theorem based on Hardy's nonlocal ladder proofs 被引量:2
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作者 GUO WeiJie FAN DaiHe WEI LianFu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第2期21-25,共5页
Bell's theorem argues the existence of quantum nonlocality which goes basically against the hidden variable theory (HVT). Many experiments have been done via testing the violations of Bell's inequalities to statis... Bell's theorem argues the existence of quantum nonlocality which goes basically against the hidden variable theory (HVT). Many experiments have been done via testing the violations of Bell's inequalities to statistically verify the Bell's theorem. Alternatively, by testing the Hardy's ladder proofs we experimentally demonstrate the deterministic violation of HVT and thus confirm the quantum nonlocality. Our tests are implemented with non-maximal entangled photon pairs generated by spontaneous parametric down conversions (SPDCs). We show that the degree freedom of photon entanglement could be significantly enhanced by using interference filters. As a consequence, the Hardy's ladder proofs could be tested and Bell's theorem is verified robustly. The probability of violating the locality reach to 41.9%, which is close to the expectably ideal value 46.4% for the photon pairs with degree of entanglement e = 0.93. The higher violating probability is possible by further optimizing the experimental parameters. 展开更多
关键词 quantum nonlocality entanglement production Hardy's proof
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parametric process quadratic waveguide array EPR state
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作者 杨莹 徐平 +1 位作者 陆亮亮 祝世宁 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第2期219-224,共6页
We propose the generation of photonic EPR state from quadratic waveguide array. Both the propagation constant and the nonlinearity in the array are designed to possess a periodical modulation along the propagation dir... We propose the generation of photonic EPR state from quadratic waveguide array. Both the propagation constant and the nonlinearity in the array are designed to possess a periodical modulation along the propagation direction.This ensures that the photon pairs can be generated efficiently through the quasi-phase-matching spontaneous parametric down conversion by holding the spatial EPR entanglement in the fashion of correlated position and anticorrelated momentum. The Schmidt number which denotes the degree of EPR entanglement is calculated and it can approach a high value when the number of illuminated waveguide channels and the length of the waveguide array are properly chosen. These results suggest the quadratic waveguide array as a compact platform for engineering photonic quantum states in a high-dimensional Hilbert space. 展开更多
关键词 Photonic EPR State from Quadratic Waveguide Array with Alternating Positive and Negative Couplings
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Experimental investigation of the influence of laser intensity on the quality of Einstein-Podolsky-Rosen entangled photons
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作者 赵加强 曹连振 逯怀新 《Optoelectronics Letters》 EI 2015年第4期317-320,共4页
Using spontaneous parametric down conversion,polarization post selection and coincidence counting technique,the polarization Einstein-Podolsky-Rosen(EPR) entangled states are prepared.Experimental studies on the effic... Using spontaneous parametric down conversion,polarization post selection and coincidence counting technique,the polarization Einstein-Podolsky-Rosen(EPR) entangled states are prepared.Experimental studies on the efficiency,contrast and fidelity with different pump laser intensities are performed systematically.The results show that the pump laser intensity distinctly influences the quality of entangled photons,especially the contrast and the fidelity.On the other hand,the pump efficiency of entangled photons is almost invariable,namely the entangled source brightness increases linearly with the increase of pump laser power. 展开更多
关键词 entangled Einstein coincidence fidelity systematically spontaneous distinctly entanglement brightness linearly
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