QCD critical end point from a realistic PNJL model

With parameters fixed by critical temperature and equation of state at zero baryon chemical potential, a realistic Polyakov--Nambu--Jona-Lasinio (rPNJL) model predicts a critical end point of chiral phase transition at $(\mu_B^E= 720 {\rm MeV}, T^E=93 {\rm MeV})$. The extracted freeze-out line from heavy ion collisions is close to the chiral phase transition boundary in the rPNJL model, and the kurtosis $\kappa \sigma^2$ of baryon number fluctuations from the rPNJL model along the experimental freeze-out line agrees well with the BES-I measurement. Our analysis shows that the dip structure of measured $\kappa\sigma^2$ is determined by the relationship between the freeze-out line and chiral phase transition line at low baryon density region, and the peak structure can be regarded as a clean signature for the existence of CEP.Comment: 8 papges, proceedings of QCD@Work 201

ShenZhen transportation system (SZTS): a novel big data benchmark suite

Data analytics is at the core of the supply chain for both products and services in modern economies and societies. Big data workloads, however, are placing unprecedented demands on computing technologies, calling for a deep understanding and characterization of these emerging workloads. In this paper, we propose ShenZhen Transportation System (SZTS), a novel big data Hadoop benchmark suite comprised of real-life transportation analysis applications with real-life input data sets from Shenzhen in China. SZTS uniquely focuses on a specific and real-life application domain whereas other existing Hadoop benchmark suites, such as HiBench and CloudRank-D, consist of generic algorithms with synthetic inputs. We perform a cross-layer workload characterization at the microarchitecture level, the operating system (OS) level, and the job level, revealing unique characteristics of SZTS compared to existing Hadoop benchmarks as well as general-purpose multi-core PARSEC benchmarks. We also study the sensitivity of workload behavior with respect to input data size, and we propose a methodology for identifying representative input data sets

Growth and Survival Determinants of Chinese Private Firms: Fieldwork evidence and econometric estimates

This paper reports on one of the first empirical attempts to investigate small firm growth and survival, and their determinants, in the Peoples’ Republic of China. The work is based on field work evidence gathered from a sample of 83 Chinese private firms (mainly SMEs) collected initially by face-to-face interviews, and subsequently by follow-up telephone interviews a year later. We extend the models of Gibrat (1931) and Jovanovic (1982), which traditionally focus on size and age alone (e.g. Brock and Evans, 1986), to a ‘comprehensive’ growth model with two types of additional explanatory variables: firm-specific (e.g. business planning); and environmental (e.g. choice of location). We estimate two econometric models: a ‘basic’ age-size-growth model; and a ‘comprehensive’ growth model, using Heckman’s two-step regression procedure. Estimation is by log-linear regression on cross-section data, with corrections for sample selection bias and heteroskedasticity. Our results refute a pure Gibrat model (but support a more general variant) and support the learning model, as regards the consequences of size and age for growth; and our extension to a comprehensive model highlights the importance of location choice and customer orientation for the growth of Chinese private firms. In the latter model, growth is explained by variables like planning, R&D orientation, market competition, elasticity of demand etc. as well as by control variables. Our work on small firm growth achieves two things. First, it upholds the validity of ‘basic’ size-age-growth models, and successfully applies them to the Chinese economy. Second, it extends the compass of such models to a ‘comprehensive’ growth model incorporating firm-specific and environmental variables

Intangible assets and determinants of firm growth in China

This paper reports on field work within Chinese small firms, aimed at acquiring data to measure the impact of intangible a ssets on firm growth. We extend a size - and age - based model to define growth as a function of size, age, entrepreneurship and intangible assets. We use statistical analysis to create measures of entrepreneurship and intangible assets from these data. Intangibles are classified into six categories: human capital; enterp rise culture, intellectual property; technology; reputation; and network. Finally, we estimate models of small firm employment growth using our new measures. For our sample, we find that entrepreneurial attributes have little significant impact on small firm growth; whereas intangible asset attributes have a positive and significant impact on growth, with networking and technological knowledge being of prime importance

The dynamics variation of soil moisture of shelterbelts along the Tarim Desert Highway

We studied the variation of soil moisture as well as its regularity over the irrigation cycle at shelterbelts along the Tarim Desert Highway at different site types and different planting years. The results show that: (1) There is an obvious temporal variation of soil moisture within a typical irrigation period in shelterbelts along the Tarim Desert Highway, and the soil water storage varied linearly with the number of days after irrigation. Along the direction perpendicular to the soil top, the soil profile can be divided into four layers and each shows different dynamics of soil moisture variation, including the quickly changing layer (0-20 cm), the active layer (20-60 cm), the weakly layer (60-100 cm), and the regulated layer (under 100 cm). (2) Both the soil moisture and soil water content decreased gradually with the number of planting year, while the soil water deficit increased. It indicates that shelterbelts along the Tarim Desert Highway can retain the water accumulated from previous years. (3) The soil water storage of harden sand is the maximum among all types of sites. Specifically, it is about 1.58 times higher than that of longitudinal dune, 1.15 times higher than clay, and 1.43 times higher than flat sand. Its soil water deficit was over 900 mm

Creencias de los profesores sobre la enseñanza del francés como lengua extranjera en una universidad china: una perspectiva multilingüe

While French is an important European language being taught in Chinese universities, not much is known about French language teachers’ beliefs about its teaching as a foreign language, particularly not from a multilingual perspective. Adopting a multiple-case design, this study examined 5 French language teachers’ beliefs about the French language and the learner. Analysing data collected via interviews, the study revealed that teachers’ beliefs reflected neither the linguistic landscape of the French language nor the learner’s existing level of multilingualism. However, the teachers’ monolingual ideology as reflected in their beliefs seemed to co-exist with beliefs that reflected their multilingual ideology; the cultural capital brought by learning French as a foreign language prevailed in teachers’ beliefs about the language with reference to the value of French learning in their students’ future international communication in a multilingual world, and the teachers also perceived their students as French learners with English learning experience that could lend support to their French learning. FUNDING INFORMATION. This research was funded by “Research on the Innovation of Foreign Language Education in China” (grant number: 22JJD740011), a major project of the Key Research Institutes of Humanities and Social Sciences under the Ministry of Education, as well as supported by the Beijing Foreign Studies University “Double First-Class” Fund (project title: “Construction of Standards for Foreign Language Education and Foreign Language Talents Training in Higher Education”, project number: 2022SYLZD010).Si bien el francés es un idioma europeo importante que se enseña en las universidades chinas, no se sabe mucho sobre las creencias de los profesores de francés sobre su enseñanza como lengua extranjera, particularmente no desde una perspectiva multilingüe. Adoptando un diseño de casos múltiples, este estudio examinó las creencias de 5 profesores de francés sobre el idioma francés y el alumno. Al analizar los datos recopilados a través de entrevistas, el estudio reveló que las creencias de los docentes no reflejaban ni el panorama lingüístico de la lengua francesa ni el nivel actual de multilingüismo del alumno. Sin embargo, la ideología monolingüe de los docentes, que se refleja en tales creencias, parecía coexistir con las creencias que reflejaban su ideología multilingüe: el capital cultural aportado por el aprendizaje del francés como lengua extranjera prevalecía en las creencias de los profesores sobre el idioma con referencia al valor del aprendizaje del francés en la futura comunicación internacional de los estudiantes en un mundo multilingüe; los profesores también percibían a sus estudiantes como estudiantes de francés con experiencia en el aprendizaje del inglés que podría ayudar al aprendizaje del francés

Single-shot 3D coherent diffractive imaging of core-shell nanoparticles with elemental specificity.

We report 3D coherent diffractive imaging (CDI) of Au/Pd core-shell nanoparticles with 6.1 nm spatial resolution with elemental specificity. We measured single-shot diffraction patterns of the nanoparticles using intense x-ray free electron laser pulses. By exploiting the curvature of the Ewald sphere and the symmetry of the nanoparticle, we reconstructed the 3D electron density of 34 core-shell structures from these diffraction patterns. To extract 3D structural information beyond the diffraction signal, we implemented a super-resolution technique by taking advantage of CDI's quantitative reconstruction capabilities. We used high-resolution model fitting to determine the Au core size and the Pd shell thickness to be 65.0 ± 1.0 nm and 4.0 ± 0.5 nm, respectively. We also identified the 3D elemental distribution inside the nanoparticles with an accuracy of 3%. To further examine the model fitting procedure, we simulated noisy diffraction patterns from a Au/Pd core-shell model and a solid Au model and confirmed the validity of the method. We anticipate this super-resolution CDI method can be generally used for quantitative 3D imaging of symmetrical nanostructures with elemental specificity

The kurtosis of net baryon number fluctuations from a realistic Polyakov--Nambu--Jona-Lasinio model along the experimental freeze-out line

Firstly we qualitatively analyze the formation of the dip and peak structures of the kurtosis $\kappa \sigma^2$ of net baryon number fluctuation along imagined freeze-out lines and discuss the signature of the existence of the QCD critical end point (CEP) in the Nambu--Jona-Lasinio (NJL) model, Polyakov-NJL (PNJL) model as well as $\mu$-dependent PNJL($\mu$ PNJL) model with different parameter sets, and then we apply a realistic PNJL model with parameters fixed by lattice data at zero chemical potential, and quantitatively investigate its $\kappa \sigma^2$ along the real freeze-out line extracted from experiments. The important contribution from gluodynamics to the baryon number fluctuations is discussed. The peak structure of $\kappa \sigma^2$ along the freeze-out line is solely determined by the existence of the CEP mountain and can be used as a clean signature for the existence of CEP. The formation of the dip structure is sensitive to the relation between the freeze-out line and the phase boundary, and the freeze-out line starts from the back-ridge of the phase boundary is required. To our surprise, the kurtosis $\kappa \sigma^2$ produced from the realistic PNJL model along the experimental freeze-out line agrees with BES-I data well, which indicates that equilibrium result can explain the experimental data. It is worth to point out that the extracted freeze-out temperatures from beam energy scan measurement are indeed higher than the critical temperatures at small chemical potentials, which supports our qualitative analysis.Comment: 15 pages, 10 figure