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21.
《Energy Policy》2005,33(11):1409-1424
This paper examines the long-run relationship between energy demand, GNP and the real energy price in Japan using data covering 1887–2001. It is found that, if an Underlying Energy Demand Trend is appropriately incorporated, the resulting econometric model produces a long-run income elasticity of about unity and a long-run price elasticity of about–0.2. The estimated model is utilised to forecast energy consumption and CO2 emissions up to 2012. It is shown that given current economic conditions and policies there is considerable uncertainty about whether Japan will be able to meet its Kyoto target by reducing CO2 emissions in 2008–2012 to the 1990 level. It is shown that this uncertainty depends on the strength of the economy and leaves the Japanese government with a difficult policy dilemma. If there is a resurgence in growth to something near the annual average growth rate since the early 1980s a considerable effort will be required in order to meet its Kyoto target; requiring not only using the Kyoto Mechanisms, but also additional tougher domestic policies and measures such as emissions capping, R&D incentives, and education for energy conservation in addition to a pricing and tax policy. 相似文献
22.
《Optical Fiber Technology》2006,12(2):110-116
We report on a newly developed in-service measurement technique that can be used from a central office to find and identify any filter in front of an ONU on an optical fiber access network. Using this system, in-service tests can be performed because the test lights are modulated at a high frequency. Moreover, by using the equipment we developed, this confirmation operation can be performed continuously and automatically with existing automatic fiber testing systems. The developed technique is effective for constructing a fiber line testing system with an optical time domain reflectometer. 相似文献
23.
《Calphad》2006,30(2):216-224
Several theoretical models for the determination of kinetic phase diagrams for solid solution growth from the liquid phase are presented and compared to each other. These models include a Monte Carlo simulation model, used as a reference model, a previously defined analytical model, based on linear non-equilibrium thermodynamics, and a new model, rooted in the kinetics at kink sites.All models have in common that the composition of the growing solid phase tends to the liquid phase composition for increasing undercooling, enhancing mixing even for systems with a strong tendency to phase separation. However, depending on the system parameters considerable quantitative differences can occur between the results from the model based on non-equilibrium thermodynamics and the MC model. Instead, the new model follows very well the trends of the MC simulations, both for well-mixing systems and for phase separating systems.For phase separating systems the analytical models predict kinetic phase separation domains, zones in the kinetic phase diagram yielding steady state growth of more than one solid phase with different compositions. According to MC simulations such domains in phase space correspond to domain formation in real space. Also in this case the new model is consistent with the MC results. 相似文献
24.
通过有限元数值模拟方法得出滚珠旋压中薄壁管在不同凹模旋转速度条件下轴向进给比的变化规律及工件的成形规律,并对模拟结果的等效应变分布做了分析,并与实验结果进行比较,给出薄壁管滚珠旋压时进给比的选取范围.结果表明,进给比对滚珠旋压中薄壁管直径的胀缩和工件的质量有着显著的影响.另外,从计算的模具所受的三向载荷变化情况分析了模具的使用寿命. 相似文献
25.
Wenwei He Wuping Liao Weiwei Wang Deqian Li Chunji Niu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(9):1314-1320
BACKGROUND: Thermodynamics and kinetics data are both important to explain the extraction property. In order to develop a novel separation technology superior to current extraction systems, many promising extractants have been developed including calixarene carboxylic acids. The extraction thermodynamics behavior of calix[4]arene carboxylic acids has been reported extensively. In this study, the mass transfer kinetics of neodymium(III) and the interfacial behavior of calix[4]arene carboxylic acid were investigated. RESULTS: The rate constant (Kao) becomes constant when the stirring speed was controlled between 250 rpm and 400 rpm. The activation energy (Ea) was calculated to be 21·41 kJ mol?1 or 88·17 kJ mol?1 (dependent on temperature) from the slope of log Kao against 1000/T. The linear relationship between the specific area and the extraction rate is the characteristic of an interfacial reaction control. The minimum bulk concentration of the extractant necessary to saturate the interface (Cmin) is lower than 4·19 × 10?4 mol L?1. CONCLUSION: The effect of stirring speed, temperature, and species concentration on the extraction rate demonstrates that the extraction regime depends on the extraction conditions. The chemical reaction control governs the extraction regime at temperatures below 303 K and a mixed control regime occurs when the temperature is between 303 K and 318 K. The probable locale for the chemical reaction is at the liquid–liquid interface and the rate equation is deduced to be: ? d[Nd3+](a)/dt = kf[Nd3+](a)[H4A](o)0·727[H+](a)?0·978. The rate‐controlling step was suggested by the analysis of the experimental results. Copyright © 2008 Society of Chemical Industry 相似文献
26.
Squeeze-film effects of perforated plates for small amplitude vibration are analyzed through modified Reynolds equation (MRE).
The analytical analysis reckons in most important influential factors: compressibility of the air, border effects, and the
resistance caused by vertical air flow passing through perforated holes. It is found that consideration of air compressibility
is necessary for high operating frequency and small ratio of the plate width to the attenuation length. The analytical results
presented in this paper agree with ANSYS simulation results better than that under the air incompressibility assumption. The
analytical analysis can be used to estimate the squeeze-film effects causing damping and stiffness added to the system. Since
the value of Reynolds number involved in this paper is low (< 1), inertial effects are neglected. 相似文献
27.
28.
《Advances in Engineering Software》2007,38(5):295-300
The paper presents the implementation of an association rules discovery data mining task using Grid technologies. For the mining task we are using the Apriori algorithm on top of the Globus toolkit. The case study presents the design and integration of the data mining algorithm with the Globus services. The paper compares the Grid version with related work in the field and we outline the conclusions and future work. 相似文献
29.
《Materials Letters》2007,61(11-12):2502-2505
Carbon microspheres with a diameter of 2 μm were prepared by hydrothermal process. The apatite-formation ability of the carbon microspheres was evaluated by soaking them in a simulated body fluid (SBF) for 5 and 10 d and apatite-formation mechanism was also analyzed. The result showed that bonelike apatite was formed on the surface of carbon microspheres. Our study indicates that the carbon microspheres synthesized by this method possess apatite-formation ability and may be used as a bioactive injectable filler for bone tissue regeneration. 相似文献
30.
M. Liu Q. Fang G. He L.Q. Zhu S.S. Pan L.D. Zhang 《Materials Science in Semiconductor Processing》2006,9(6):876
High-k HfOxNy thin films have been grown by radio frequency (rf) reactive sputtering of metal Hf target in N2/Ar/O2 ambient at different substrate temperatures. The chemical compositions of the films have been investigated as a function of substrate temperature by X-ray photoelectron spectroscopy (XPS). XPS measurements showed that nitrogen concentration increases with an increase in substrate temperature. Room-temperature spectroscopic ellipsometry (SE) with photon energy 0.75–6.5 eV was used to investigate the optical properties of the films. SE results demonstrated that refractive index n increases with an increase in substrate temperature. Based on TL parameters which were obtained from the best fit results used in a simulation of the measured spectra, meanwhile, we conclude that the energy band gap (Eg) decreases with an increase in substrate temperature. 相似文献