Results 1 - 10 of 449
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[en] A scheme for probabilistic and controlled teleportation of the unknown quantum states of both one-particle and two-particle is proposed. In this scheme the teleportation is not always successful but with certain probability
[en] This paper is based on dynamic optimization methodology to investigate the economic energy efficiency issues in developing countries. The paper introduces some definitions about energy efficiency both in economics and physics, and establishes a quantitative way for measuring the economic energy efficiency. The linkage between economic energy efficiency, energy consumption and other macroeconomic variables is demonstrated primarily. Using the methodology of dynamic optimization, a maximum problem of economic energy efficiency over time, which is subjected to the extended Solow growth model and instantaneous investment rate, is modelled. In this model, the energy consumption is set as a control variable and the capital is regarded as a state variable. The analytic solutions can be derived and the diagrammatic analysis provides saddle-point equilibrium. A numerical simulation based on China is also presented; meanwhile, the optimal paths of investment and energy consumption can be drawn. The dynamic optimization encourages governments in developing countries to pursue higher economic energy efficiency by controlling the energy consumption and regulating the investment state as it can conserve energy without influencing the achievement of steady state in terms of Solow model. If that, a sustainable development will be achieved. - Highlights: • A new definition on economic energy efficiency is proposed mathematically. • A dynamic optimization modelling links economic energy efficiency with other macroeconomic variables in long run. • Economic energy efficiency is determined by capital stock level and energy consumption. • Energy saving is a key solution for improving economic energy efficiency
[en] As one of the ways for solid free-form fabrication, jet-printing technique directly deposits the ceramic sols on a substrate to form ceramic films using a ink-jet printer. In this process, the properties of ceramic sols are the key to determine the printing effect. In this paper, Ba-Ti, Sr-Ti and Ba-Sr-Ti sols used for ceramic film jet-printing were prepared using barium acetate, strontium acetate and tetrabutyl titanate as starting materials. The properties of the sols were determined and adjusted successfully through the variation of processing parameters. Formamide was added into the sols to improve the stability and the viscosity of the sols. For a constant concentration of ethylene glycol, the stability of the sol increases and the viscosity of the sol decreases as the concentration of formamide increases. The concentration ratio of acetic acid to ethylene glycol Rac/eg is crucial to obtain stable sols for jet-printing process. The optimal Rac/eg value is 3:1 for Sr-Ti sols, 3:2 for Ba-Ti and Ba-Sr-Ti sols
[en] The luminosity upgrades of Beijing Electron-Positron Collider (BEPC) and the design studies of Beijing τ-charm Factory (BTCF) in recent years will be reviewed. BEPC luminosity upgrades mainly with lower-β scheme have been performed in recent years. By lowering the vertical β function at interaction point from 8.5 cm to 5.0 cm the peak luminosity is nearly doubled at 1.55 GeV. The performance of dedicated synchrotron radiation operation is significantly improved by installing new insertion device and increasing the beam lifetime. The future upgrade options in BEPC are briefly discussed. The design studies of a new e+e- collider facility called Beijing τ-charm Factory have been making progress continuously. Besides the very high luminosity, say, specifically 1x1033 cm-2s-1 at 2.0 GeV, BTCF is able to yield the high longitudinal polarization and the possibility of monochromator collision. In recent design studies the higher luminosity scheme with shorter bunch spacing by adopting larger crossing angle is investigated. A comparison between vertically and horizontally separated rings layout is made. The monochromator scheme with vertical crossing angle is explored which is compatible to the large horizontal crossing angle option and possible to reach much higher luminosity than that of head-on monochromator collision. (author)
[en] It introduces the source of background and the ways to reduce the background when filter-fluorescence method is used to measure X-ray energy spectrum, and analyzes the approximate conditions of numerical calculation of signal and noise, regrading the 'high-energy-tail' as the main background, Signal-to-Noise Ratio of Ca-K, V-Ti of different thickness combination and current output of PIN detector in perfect state are calculated at both temperature 7 x 106 K and 10 x 106 K. (authors)
[en] It simulates electric fields by the charge simulation method in two conditions that the emission electrode is plane plate and the target electrode is plane plate and sphere respectively, and calculated the kinetic parameters of accelerated ion. The results show that ions can get more energy with smaller center hole of emission electrode, and that spheric shape target electrode has higher-usage of core area than that of plane plate target electrode. (authors)
[en] This paper describes study on exchange properties of Cs+ in Alkali-Activated Slag Cement (AASC) solidified forms of simulated High-level Radioactive Liquid Waste (HLRW) by adding NiSO4 and K4[Fe(CN)6]. The results show that the exchanging rate for Cs+ is relative rapid, in the wide range of both pH and temperature. At 25 degree C, after 42 days, the leaching rate of Cs+ from AASC solidified from is at the level of 10-6 cm·d-1 (adapting China's National Standard 7023-86), 3.24% of the rate from the original form. At 90 degree C, after 28 days, that leaching rate of Cs+ is at the level of 10-4 g·cm-2·d-1 (adapting MCC-1 method), 4.85% of the rate from the original form
[en] In order to explore the nature of density fluctuations in the edge of magnetically confined fusion plasmas, the technique of permutation entropy and statistical complexity is used. The location of fluctuations on the entropy versus complexity plane classifies the dynamical behaviour of the system. The behaviour can be differentiated between stochastic and chaotic. The latter is supposed to be connected to a specific temporal form of intermittent density events, i.e. blobs, in the scrape-off layer (SOL). In this contribution, density fluctuations measured with a Langmuir probe in the torsatron TJ-K are analyzed with respect to the dynamical nature. Radial scans are performed across the separatrix to distinguish the dynamics in the inner edge and the SOL. Comparisons with well known test systems indeed point to a qualitative change in the dynamics across the separatrix. In the region of maximum density gradient, the fluctuations are characterized by minimum entropy. The results will be discussed on separated scales.
[en] Coastal areas have great significance for human living, economy and society development in the world. With the rapid increase of pressures from human activities and climate change, the safety of groundwater resource is under the threat of seawater intrusion in coastal areas. The area of Laizhou Bay is one of the most serious seawater intruded areas in China, since seawater intrusion phenomenon was firstly recognized in the middle of 1970s. This study assessed the pollution risk of a groundwater source filed of western Laizhou Bay area by inferring the probability distribution of groundwater Cl− concentration. The numerical model of seawater intrusion process is built by using SEAWAT4. The parameter uncertainty of this model is evaluated by Markov Chain Monte Carlo (MCMC) simulation, and DREAM(ZS) is used as sampling algorithm. Then, the predictive distribution of Cl- concentration at groundwater source field is inferred by using the samples of model parameters obtained from MCMC. After that, the pollution risk of groundwater source filed is assessed by the predictive quantiles of Cl- concentration. The results of model calibration and verification demonstrate that the DREAM(ZS) based MCMC is efficient and reliable to estimate model parameters under current observation. Under the condition of 95% confidence level, the groundwater source point will not be polluted by seawater intrusion in future five years (2015–2019). In addition, the 2.5% and 97.5% predictive quantiles show that the Cl− concentration of groundwater source field always vary between 175 mg/l and 200 mg/l. - Highlights: • The parameter uncertainty of seawater intrusion model is evaluated by MCMC. • Groundwater source field won’t be polluted by seawater intrusion in future 5 years. • The pollution risk is assessed by the predictive quantiles of Cl− concentration
[en] In this paper, we focus on the reliability of Weibull distribution under multiply Type-I censoring, which is a general form of Type-I censoring. In multiply Type-I censoring in this study, all units in the life testing experiment are terminated at different times. Reliability estimation with the maximum likelihood estimate of Weibull parameters is conducted. With the delta method and Fisher information, we propose a confidence interval for reliability and compare it with the bias-corrected and accelerated bootstrap confidence interval. Furthermore, a scenario involving a few expert judgments of reliability is considered. A method is developed to generate extended estimations of reliability according to the original judgments and transform them to estimations of Weibull parameters. With Bayes theory and the Monte Carlo Markov Chain method, a posterior sample is obtained to compute the Bayes estimate and credible interval for reliability. Monte Carlo simulation demonstrates that the proposed confidence interval outperforms the bootstrap one. The Bayes estimate and credible interval for reliability are both satisfactory. Finally, a real example is analyzed to illustrate the application of the proposed methods. - Highlights: • We focus on reliability of Weibull distribution under multiply Type-I censoring. • The proposed confidence interval for the reliability is superior after comparison. • The Bayes estimates with a few expert judgements on reliability are satisfactory. • We specify the cases where the MLEs do not exist and present methods to remedy it. • The distribution of estimate of reliability should be used for accurate estimate.