Evaluating the relationship between the academic and social impact of open access books based on citation behaviors and social media attention

Scientometrics - Open access academic achievements include not only papers and journals, but also books, which have become an important achievement for scholars and can be regarded as scholarly...     

An empirical study on the utilization of web academic resources in humanities and social sciences based on web citations

In this era of a rapid change in the way people finding and using information resources, despite that the academic communication and using patterns for people in the traditional print environment have been studied for many years, the Internet media presents a new and relatively unexplored area for such study. In this article, we explored the distribution and utilization of web recourses in humanities and social sciences based on web citations. We collected 1,421,731 citations listed in 148,172 articles from 493 journals published during the period of 2006–2007 in the CSSCI, which resulted in 44,973 web citations. We counted the amount and types of web resources used in various disciplines, analyzed the URLs frequency from the host-level, fitted the frequency distribution into the regression models with SPSS, and perform the disciplines coupling analysis based on the web citations. We found out that: (a) The distributions of web citations by years or by websites and webpage types are selective and regular; (b) Great disparity exists among various disciplines in terms of using web information, and the high-frequency websites; (c) The frequency distribution of web citations is similar to the Garfield’s citation distribution curve; (d) Some relationships between disciplines are detected, based on the utilization of web information.     

Analysis on dynamics of research sub-domains in interdisciplinary fields: Analysis using personal distribution versus papers

Theoretically, we first classified interdisciplinary research to three types: 1) creating new field from inside of the scientific community, 2) collaboration among disciplines lead by the societal needs outside of the scientific community, 3) making suggestions for public. For analysis on dynamics of knowledge combination in interdisciplinary research, we developed an indicator using relative transmission concept and also sub-domain maps using quantification factor analysis (1974). We used a sub-domain matrix, which show the structure of submitting crossing over several sub-domains from one individual. Using researcher as a unit of the analysis, we analyzed dynamics of the blends / separation of sub-domain in interdisciplinary studies. Biophysics and environmental science, which are categorized as 1) and 2) in the above theoretical types, are chose for analysis. The total numbers of researchers are 516 and 346, in each field respectively, and observation year points are 1966, 1972, 1979, and 1984 for biophysics and 1977 and 1983 for environmental science. The results showed that the structure of groups of sub-domains in environmental science reflects the classical disciplines and there observed little combination in the knowledge, whereas in biophysics, the sub-domains are not fixed and there observed dynamics in knowledge integration. These tendency are considered to reflect the characteristics of the type- 2) and type- 1), respectively.     

Aerosol extinction models based on measurements at two sites in Sweden

Two aerosol extinction models have been developed using statistical analysis of long-term optical transmission measurements in Sweden performed at two locations from July 1977 to June 1982. The aerosol volume extinction coefficient for infrared (IR) radiation is calculated by the models with visibility, temperature, and air pressure as input parameters. As in the MODTRAN model, the IR extinction coefficient is proportional to the coefficient at 550 nm, which depends on the visibility. In the new models, the wavelength dependence of the extinction also depends on the visibility. The models predict significantly higher attenuation in the IR than does the Rural aerosol model from MODTRAN, which is commonly used. Comparison with the Maritime model shows that the new models predict lower extinction values in the 3-5 microm region and higher values in the 8-12 microm region. The uncertainties in terms of variance levels are calculated by the models. The properties of aerosols, and thereby the extinction coefficient, are partly correlated to local meteorological parameters, which enables the calculation of a mean predicted value. A substantial part of the variation is, however, caused by conditions in the source area and along the trajectory path of the aerosols. They are not correlated to the local meteorological parameters and therefore cause the variance in the models.     

The impact of driver age on lost life years for other road users in France: A population based study of crash-involved road users

BACKGROUND: One of the concerns in road safety is the threat older drivers may pose to other road users. Using the rate of lost life years, the present study provides a public health approach to quantify this potential threat. METHODS: A total of 1570686 motorised vehicle drivers or motorcycle riders and 652246 non-drivers, i.e. vehicle passengers, pedestrians and cyclists involved in injury crashes in France between 1996 and 2004, were included in a population based cross-sectional study. Fatality rates and rate of lost life years for each crash-involved driver age class were calculated for the drivers themselves and for other road users. RESULTS: The study has shown a significant reduction in the rate of lost life years for crash-involved other road users (whether passengers, pedestrians, cyclists or opposing drivers) as driver age increases. Other road users lost half as many years of life when involved in crashes with drivers aged over 85 than with drivers under 65 (1.26 and 2.32 per 100 expected remaining life years, respectively). CONCLUSION: Our findings suggest that among road users involved in injury crashes, older drivers are less dangerous for the other road users. By attributing other road users' lost life years to each driver age, this study represents a new contribution to the debate about ageing and road safety.     

基于CFD方法的孔板送风气流组织优化研究

以采用孔板送风的空调房间为研究对象,通过计算流体力学(CFD)方法进行建模和模拟计算,采用正交试验设计及其极差和方差分析法分析模拟结果,综合考虑各因素对不均匀性系数、面平均速度和面平均温度的影响规律,发现其影响由大至小依次为送风量、孔板层高度、孔隙率和有无支风管。在无支风管条件下,孔板层高度为3 m、孔隙率为35%、风量为1 000 m3/h时流场均匀性最好。     

Temperature distribution in SFCLs based on Au/YBCO films during quenches

We investigated temperature distribution in SFCLs based on Au/YBa₂Cu₃O₇ (YBCO). SFCLs were fabricated by patterning Au/YBCO thin films grown on sapphire substrates into meander lines by photolithography. A gold film grown on the back side of the substrate was patterned into a meander line, and used as a thermometer. The front meander line was subjected to simulated AC fault currents, and the back line to DC current. Resistance of the front and back meander lines were measured and analyzed. The SFCLs were immersed in liquid nitrogen during the experiment for effective cooling. The temperature at the back side was close to that at the front side, and was closer at lower temperatures. This was observed at all stripes. The oscillatory component of the resistance of the back meander line is smaller than, and out-of-phase with that of the front meander line, which was more pronounced at higher temperatures. These results were analyzed quantitatively with the concept of heat transfer within the SFCL and to surroundings. Solutions for a heat equation explained the temperature distribution in SFCLs quantitatively: data coincided well with the solutions. In addition, quench development near the quench start point could be understood better than before, using the results.     

Identification of static load characteristics based on measurements in medium-voltage distribution network

The authors deal with static load (SL) characteristics (P-V and Q-V characteristics) of a medium-voltage distribution network derived from field measurements. The experiments have been performed by changing the tap position of an on-load tap-changing transformer in different seasons, different week days and day periods. P-V and Q-V load characteristics are divided into two classes, transient and steady-state characteristics. The differences between them are discussed and quantified. Both classes are mathematically described by polynomial, linear and exponential SL models. Model parameters are obtained by curve fitting using a least square method. The adequacy of developed load models is critically assessed and discussed. All the static characteristics are grouped according to seasons and day periods and are mutually compared. Finally, the parameters of the SL models for residential load without electrical heating are suggested for different seasons.     

Exploring the relationships between altmetric counts and citations of papers in different academic fields based on co-occurrence analysis

Scientometrics - Altmetrics is an emerging method for observing academic communication. Many researchers have explored the relationships between altmetric counts and citations through correlation...     

基于M-C方法模拟分析NBI真空压力分布的影响因素

中性束注入装置(Neutral Beam Injector,NBI)是产生高能中性粒子束用以加热托卡马克等离子体的装置.NBI真空压力分布是影响中性束传输效率特别是再电离损失的关键因素之一.本文研究分析了HT-7托卡马克NBI实验装置的工作原理和结构特点,利用Monte-Carlo方法建立NBI实验装置主真空室及飘移管道内分子运动及碰撞的相关模型,并进行编程实现对NBI实验装置真空压力分布模拟计算.模拟计算和实验结果表明:主真空室低温冷凝泵抽速为4×105L/s时,主真空室压力在脉冲充气过程中维持在10-3Pa量级;飘移管道低温冷凝泵抽速为4×104 L/s时,飘移管道压力维持在10-4Pa量级.文章的结论为中性束传输过程中再电离损失的研究提供了理论依据.     

基于Monte-Carlo方法模拟分析NBI真空压力分布的研究

中性束注入装置是产生高能中性粒子以加热托卡马克等离子体的装置。NBI真空压力分布是影响中性束传输效率特别是再电离损失的关键因素之一。研究分析了超导托卡马克实验装置中NBI的工作原理和结构特点,建立了EAST NBI的几何与物理模型,利用Monte-Carlo方法建立NBI主真空室内分子运动及碰撞的数学模型,并运用Matlab软件编程实现对NBI主真空室内真空压力分布的模拟计算,得到主真空室内三段区域在进气过程中的气体分子三维分布图和平均压力变化曲线。研究可为EAST NBI主真空室内的中性化室、偏转系统、低温抽气系统的结构设计提供指导。     

Monitoring changes in the error distribution of autoregressive models based on Fourier methods

We develop a procedure for monitoring changes in the error distribution of autoregressive time series while controlling the overall size of the sequential test. The proposed procedure, unlike standard procedures which are also referred to, utilizes the empirical characteristic function of properly estimated residuals. The limit behavior of the test statistic is investigated under the null hypothesis as well as under alternatives. Since the asymptotic null distribution contains unknown parameters, a?bootstrap procedure is proposed in order to actually perform the test and corresponding results on the finite?Csample performance of the new method are presented. As it turns out the procedure is not only able to detect distributional changes but also changes in the regression coefficient.     

Goodness-of-fit tests in parametric regression based on the estimation of the error distribution

Consider a heteroscedastic regression model Y=m(X)+σ(X)ε, where m(X)=E(Y|X) and σ ²(X)=Var (Y|X) are unknown, and the error ε is independent of the covariate X. We propose a new type of test statistic for testing whether the regression curve m(⋅) belongs to some parametric family of regression functions. The proposed test statistic measures the distance between the empirical distribution function of the parametric and of the nonparametric residuals. The asymptotic theory of the proposed test is developed, and the proposed testing procedure is illustrated by means of a small simulation study and the analysis of a data set.     

Study on mechanism of strength distribution development in vacuum-dewatered concrete based on the consolidation theory

The strength and hardness of a concrete slab surface are considered to be significantly affected by concrete bleeding. Vacuum dewatering is reported to be quite effective in imparting high density and strength. However, in Japan, in contrast with concrete work in civil engineering applications, concrete work in the field of building construction has not been successfully treated by this method. In an earlier report, the authors pointed out the strong relationship between strength distribution and density distribution in vacuum-dewatered concrete, both of which gradually decrease from the top surface to a depth of about 15 cm. The main purpose of the present study is to discuss the mechanism of the occurrence of such distribution of strength and density, based on consolidation theory. In an experiment, pore water pressure distribution in concrete is measured by means of an original measuring system. The results of the experiment confirm that the consolidation theory is quite effective in explaining the internal properties of vacuum-dewatered concrete as well as those of press-dewatered concrete. A prediction method for the strength improvement of concrete by vacuum dewatering is also discussed. It was considered likely that pore water pressure distribution generated by vacuum dewatering could be attributable to the influences of capillary tension and viscous resistance. This mechanism was verified by model experiment.     

A study on liquid-liquid distribution based on single picoliter droplets and in situ electrochemical measurements

A microelectrode technique combined with the microcapillary injection/manipulation of a single organic droplet in water was developed. The technique was applied to the study of the distribution of a ferrocene derivative across a single-picoliter-nitrobenzene-droplet/water interface and to the simultaneous in situ electrochemical determination of the distributed solute in the picomole-femtomole range. The liquid-liquid distribution processes were discussed in terms of droplet size and solute concentration (in water) dependencies of the interfacial mass transfer rate.     

Optimal distribution of oil products in oil tanks based on qualitative determination in the tanks

An analytic expression for the optimal distribution of oil products in oil tanks that minimizes the measurement error of the total mass of the oil products in the tanks is determined. A simple algorithm for implementing the optimal distribution which is easy to use in selecting an optimal variant is developed. Translated from Izmeritel’naya Tekhnika, No. 1, pp. 27–30, January, 1998.     

ICP-OES和ICP-MS方法分析郫县豆瓣中矿物质元素的分布

通过优化微波消解郫县豆瓣样品预处理方法,建立电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体发射光谱法(ICP-OES)检测郫县豆瓣中14种矿物质元素(K、P、Al、Fe、Cu、Ca、Zn、Mn、Mg、Se、Pb、Cd、Cr、As)的定量分析方法,并对不同发酵时间的郫县豆瓣进行检测。得到Pb、Cd、Cr、As的检出限分别为:0.110μg/kg、0.014μg/kg、0.269μg/kg、0.132μg/kg,加标回收率介于91.1%～109.8%;K、P、Al、Fe、Cu、Ca、Zn、Mn、Mg、Se检出限介于0.0014～0.0328 mg/kg,加标回收率在91.9%～117.7%之间。对不同后发酵时长(1～11个月)郫县豆瓣中矿物质元素分布进行检测,结果显示在该时间范围内同一元素含量变化无显著性差异;Pb、Cd、Cr、As的残留量均远低于国标限量,显示郫县豆瓣在此方面的安全性。测试结果准确、高效,表明该方法具有良好的检测应用前景。     

基于样本密度KFCM新算法及其在故障诊断的应用

摘要：针对传统核模糊聚类(KFCM)算法无法克服边界噪声数据影响且对初始聚类中心敏感的不足,提出一种基于样本密度和最大类间方差法相结合的KFCM算法。该算法在传统的KFCM算法中引入样本分布密度作为权重,克服噪声及边界数据对分类中心的影响,使样本的聚类效果更好,同时还可以分析各样本对聚类的贡献程度。此外利用最大类间方差法对样本密度进行分割,得到各类中心点并以此作为KFCM算法的初始聚类中心,克服了传统算法对初始值敏感的不足。对各种实际数据集的测试结果均显示出新算法的优良性能。最后利用新算法对轴承故障进行诊断,试验结果表明新算法的诊断率优于传统的聚类算法。     

The role of squeezing in quantum key distribution based on homodyne detection and post-selection

Abstract

The role of squeezing in quantum key distribution with continuous variables based on homodyne detection and post-selection is investigated for several specific eavesdropping attacks. It is shown that amplitude squeezing creates strong correlations between the signals of the legitimate receiver and a potential eavesdropper. Post-selection of the received pulses can therefore be used to reduce the eavesdropper's knowledge of the raw key, which increases the secret key rate by orders of magnitude over large distances even for modest amounts of squeezing.     

Afterpulsing model based on the quasi-continuous distribution of deep levels in single-photon avalanche diodes

We have performed a statistical characterization of the effect of afterpulsing in a free-running silicon single-photon detector by measuring the distribution of afterpulse waiting times in response to pulsed illumination and fitting it by a sum of exponentials. We show that a high degree of goodness of fit can be obtained for five exponentials, but the physical meaning of estimated characteristic times is dubious. We show that a continuous limit of the sum of exponentials with a uniform density between the limiting times gives excellent fitting results in the full range of the detector response function. This means that in certain detectors, the afterpulsing is caused by a continuous band of deep levels in the active area of the photodetector.