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“拒绝”与“回绝”语义对比分析
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作者 朱沂蒙 《现代语文》 2021年第10期81-85,共5页
以现代汉语同义词“拒绝”与“回绝”为研究对象,运用语义特征分析法和三个平面语法理论,从动作行为、行为主体对象、行为连带对象三个方面,对二者进行全面系统的语义对比分析,揭示其中的同与异。为今后的对外汉语教学提供有益的参考,... 以现代汉语同义词“拒绝”与“回绝”为研究对象,运用语义特征分析法和三个平面语法理论,从动作行为、行为主体对象、行为连带对象三个方面,对二者进行全面系统的语义对比分析,揭示其中的同与异。为今后的对外汉语教学提供有益的参考,帮助留学生掌握其基本用法,减少使用偏误。 展开更多
关键词 “拒绝” “回绝” 同义词 语义对比 对外汉语教学
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Quasi-Static Energy Recovery Logic with Single Power-Clock Supply
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作者 李舜 周锋 +2 位作者 陈春鸿 陈华 吴一品 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1729-1734,共6页
This paper presents a new quasi-static single-phase energy recovery logic (QSSERL), which unlike any other existing adiabatic logic family,uses a single sinusoidal supply-clock without additional timing control volt... This paper presents a new quasi-static single-phase energy recovery logic (QSSERL), which unlike any other existing adiabatic logic family,uses a single sinusoidal supply-clock without additional timing control volta- ges. This not only ensures lower energy dissipation, but also simplifies the clock design, which would be otherwise more complicated due to the signal synchronization requirement. It is demonstrated that QSSERL circuits operate as fast as conventional two-phase energy recovery logic counterparts. Simulation with an 8bit logarithmic look- ahead adder (LLA) using static CMOS,clocked CMOS adiabatic logic (CAL,an existing typical single-phase ener- gy recovery logic),and QSSERL,under 128 randomly generated input vectors,shows that the power consumption of the QSSERL adder is only 45% of that of the conventional static CMOS counterpart at 10MHz, and the QS- SERL adder achieves better energy efficiency than CAL when the input frequency finput is larger than 2MHz. 展开更多
关键词 energy recovery adiabatic logic low power digital CMOS VLSI
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Characterizing pressure fluctuation into single-loop oscillating heat pipe 被引量:3
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作者 PARK Yong-ho Md.Riyad Tanshen +2 位作者 Md.J.Nine CHUNG Han-shik JEONG Hyo-min 《Journal of Central South University》 SCIE EI CAS 2012年第9期2578-2583,共6页
The pressure characteristics inside single loop oscillating heat pipe (OHP) having 4.5 mm inner diameter copper tube with the loop height of 440 mm were addressed. Distilled water was used as working fluid inside th... The pressure characteristics inside single loop oscillating heat pipe (OHP) having 4.5 mm inner diameter copper tube with the loop height of 440 mm were addressed. Distilled water was used as working fluid inside the OHP with different filling ratios of 40%, 60% and 80% of total inside volume. Experimental results show that the thermal characteristics are significantly inter-related with pressure fluctuations as well as pressure frequency. And the pressure frequency also depends upon the evaporator temperature that is maintained in the range of 60-96 ℃. Piezoresistive absolute pressure sensor (Model-Kistler 4045A5) was used to take data. The investigation shows that the filling ratio of 60% gives the highest inside pressure magnitude at maximum number of pressure frequency at any of set evaporator temperature and the lowest heat flow resistance is achieved at 60% filling ratio. 展开更多
关键词 oscillating heat pipe pressure fluctuation heat flow resistance filling ratio
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A Quantitative Structure Property Relationship for Prediction of Flash Point of Alkanes Using Molecular Connectivity Indices 被引量:3
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作者 Morteza Atabati Reza Emamalizadeh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期420-426,共7页
Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecul... Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecular structure without any experimental effort, they provide a simple and straightforward method for property prediction. In this work the flash point of alkanes was modeled by a set of molecular connectivity indices (Х), modified molecular connectivity indices ( ^mХ^v ) and valance molecular connectivity indices ( ^mХ^v ), with ^mХ^v calculated using the hydrogen perturbation. A stepwise Multiple Linear Regression (MLR) method was used to select the best indices. The predicted flash points are in good agreement with the experimental data, with the average absolute deviation 4.3 K. 展开更多
关键词 quantitative structure property relationship flash point molecular connectivity indices hydrogen perturbation ALKANE
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Short Term Wind Power Prediction Using Wavelet Transform and ARIMA
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作者 In-Yong Seo Bok-Nam Hat +3 位作者 Sang-Ok Kin Won Nam-Koong Dong-Wan Seo Seong-JunKim 《Journal of Energy and Power Engineering》 2012年第11期1786-1790,共5页
A sustainable production of electricity is essential for low carbon green growth in South Korea. Although wind energy is unlimited in potential, both intermittency and volatility should be tackled for smart grid integ... A sustainable production of electricity is essential for low carbon green growth in South Korea. Although wind energy is unlimited in potential, both intermittency and volatility should be tackled for smart grid integration in future. To cope with this, many works have been done for wind speed and power forecasting. It is shown that statistical techniques are useful for short-term forecasting of wind power. This paper presents a statistical wind speed forecasting. The wavelet decomposition is employed as a de-noising technique. An illustration will be given by real-world dataset. According to the result, the MAD (mean absolute deviation) is improved as much as 10%. 展开更多
关键词 Wind speed forecasting autoreressive model wavelet decomnosition mean absolute deviation.
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A new group contribution-based method for estimation of flash point temperature of alkanes
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作者 戴益民 刘辉 +5 位作者 陈晓青 刘又年 李浔 朱志平 张跃飞 曹忠 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期30-36,共7页
Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple li... Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple linear regression(MLR)and artificial neural network(ANN). This simple linear model shows a low average relative deviation(AARD) of 2.8% for a data set including 50(40 for training set and 10 for validation set) flash points. Furthermore, the predictive ability of the model was evaluated using LOO cross validation. The results demonstrate ANN model is clearly superior both in fitness and in prediction performance.ANN model has only the average absolute deviation of 2.9 K and the average relative deviation of 0.72%. 展开更多
关键词 flash point alkane group contribution artificial neural network(ANN) quantitative structure-property relationship(QSPR)
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RANDOM WEIGHTING METHOD FOR CENSORED REGRESSION MODEL 被引量:7
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作者 ZHAOLincheng FANGYixin 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2004年第2期262-270,共9页
Rao and Zhao (1992) used random weighting method to derive the approximate distribution of the M-estimator in linear regression model.In this paper we extend the result to the censored regression model (or censored “... Rao and Zhao (1992) used random weighting method to derive the approximate distribution of the M-estimator in linear regression model.In this paper we extend the result to the censored regression model (or censored “Tobit” model). 展开更多
关键词 censored regression least absolute deviations estimates random weighting BOOTSTRAP
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Retracts, fixed point property and existence of periodic points
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作者 麦结华 《Science China Mathematics》 SCIE 2001年第11期1381-1386,共6页
Let X be a metric space, f∈ C0(X), and V X. The set-trajectory ( V, f( V),…,fn(V)) is investigated and some conditions for f to have periodic points with given periods are obtained.
关键词 periadic point PERIOD return set-trajectory absolute retract fixed point property
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Nonadiabatic acceleration of plasma sheet ions related to ion cyclotron waves 被引量:3
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作者 WANG Zhi Qiang CAO Jin Bin +2 位作者 RME Henri DANDOURAS Iannis MA Yu Duan 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2434-2440,共7页
The nonadiabatic acceleration of plasma sheet ions is important to the understanding of substorm energetic injections and the formation of ring current. Previous studies show that nonadiabatic acceleration of protons ... The nonadiabatic acceleration of plasma sheet ions is important to the understanding of substorm energetic injections and the formation of ring current. Previous studies show that nonadiabatic acceleration of protons by magnetic field dipolarization is hard to occur at X>–10 RE because the time-scale of dipolarization(several minutes) is much larger than the gyroperiod of protons there(several seconds). In this paper, we present a case of nonadiabatic acceleration of plasma sheet ions observed by Cluster on October 30, 2006 at(XGSM, YGSM)=(-7.7, 4.7) RE. The nonadiabatic acceleration of ions is caused not by previously reported magnetospheric dipolarization but by the ultra low frequency(ULF) waves during magnetospheric dipolarization. The nonadiabatic acceleration of ions generates a new energy flux structure of ions, which is characterized by the usual energy flux increase of ions(28–80 ke V) and a concurrent energy flux decrease of ions in a lower energy range(10 e V–20 ke V). These new observations constitute a complete physical picture: The lower energy ions absorb the wave energy, and thus get accelerated to higher energy. We use a nonadiabatic model to interpret the ion energy flux variations. Both analytic and simulation results are in good agreement with the observations. This indicates that the nonadiabatic acceleration associated with ULF waves superposed on dipolarized magnetic field is an effective mechanism for ion energization in the near-Earth plasma sheet. The presented energy flux structures can be used as a proxy to identify the similar dynamic process. 展开更多
关键词 nonadiabatic acceleration ion cyclotron waves wave-particle interaction
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Prediction of thermal conductivity of polymer-based composites by using support vector regression 被引量:2
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作者 WANG GuiLian CAI CongZhong +1 位作者 PEI JunFang ZHU XingJian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第5期878-883,共6页
Support vector regression (SVR) combined with particle swarm optimization (PSO) for its parameter optimization, was proposed to establish a model to predict the thermal conductivity of polymer-based composites under d... Support vector regression (SVR) combined with particle swarm optimization (PSO) for its parameter optimization, was proposed to establish a model to predict the thermal conductivity of polymer-based composites under different mass fractions of fillers (mass fraction of polyethylene (PE) and mass fraction of polystyrene (PS)). The prediction performance of SVR was compared with those of other two theoretical models of spherical packing and flake packing. The result demonstrated that the estimated errors by leave-one-out cross validation (LOOCV) test of SVR models, such as mean absolute error (MAE) and mean absolute percentage error (MAPE), all are smaller than those achieved by the two theoretical models via applying identical samples. It is revealed that the generalization ability of SVR model is superior to those of the two theoretical models. This study suggests that SVR can be used as a powerful approach to foresee the thermal property of polymer-based composites under different mass fractions of polyethylene and polystyrene fillers. 展开更多
关键词 polymer matrix composites thermal conductivity support vector regression regression analysis PREDICTION
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