双层摊铺技术在沥青混凝土路面施工中的应用

本文主要对双层摊铺技术在沥青混凝土路面施工中的作用、施工准备及应用进行了分析与探究。     

A Statistical Model to Investigate the Reproducibility Rate Based on Replication Experiments

The reproducibility crisis, that is, the fact that many scientific results are difficult to replicate, pointing to their unreliability or falsehood, is a hot topic in the recent scientific literature, and statistical methodologies, testing procedures and p‐values, in particular, are at the centre of the debate. Assessment of the extent of the problem–the reproducibility rate or the false discovery rate–and the role of contributing factors are still an open problem. Replication experiments, that is, systematic replications of existing results, may offer relevant information on these issues. We propose a statistical model to deal with such information, in particular to estimate the reproducibility rate and the effect of some study characteristics on its reliability. We analyse data from a recent replication experiment in psychology finding a reproducibility rate broadly coherent with other assessments from the same experiment. Our results also confirm the expected role of some contributing factor (unexpectedness of the result and room for bias) while they suggest that the similarity between original study and the replica is not so relevant, thus mitigating some criticism directed to replication experiments.     

Cox Point Processes: Why One Realisation Is Not Enough

We review a rich class of point process models, Cox point processes, and illustrate the necessity of more than one observation (point patterns) in performing parameter estimation. Furthermore, we introduce a new Cox point process model by treating the intensity function of the underlying Poisson point process as a random mixture of normal components. The behaviour and performance of the new model are compared with those of popular Cox point process models. The new model is exemplified with an application that involves a single point pattern corresponding to earthquake events in California, USA.     

Interpoint Distance Test of Homogeneity for Multivariate Mixture Models

Finite mixtures offer a rich class of distributions for modelling of a variety of random phenomena in numerous fields of study. Using the sample interpoint distances (IPDs), we propose the IPD‐test statistic for testing the hypothesis of homogeneity of mixture of multivariate power series distribution or multivariate normal distribution. We derive the distribution of the IPDs that are drawn from a finite mixture of the multivariate power series distribution and multivariate normal distribution. Based on the empirical distribution of the IPDs, we construct a bootstrap test of homogeneity for other multivariate finite mixture models. The IPD test is applied to mixture models for matrix‐valued distributions and a test of homogeneity for Wishart mixture is presented. Numerical comparisons show that IPD test has accurate type I errors and is more powerful in most multivariate cases than the expectation–maximization (EM) test and modified likelihood ratio test.     

PLC液压控制系统在桥梁整体同步顶升中的应用

新建桥梁与原有旧桥梁的对接如何进行,尤其是对刚投入使用不久的桥梁改造,应从经济、环保、交通、使用价值安全等多方面考虑。桥梁整体可靠程度将直接影响桥梁结构的安全度和耐久性,PLC液压控制系统能够有效解决桥梁上部结构在顶升、降落过程中同步位移的难题,保证桥梁的整体性。     

如何在施工过程中控制沥青路面平整度

路面平整度是评定路面质量和衡量公路使用性能的一项重要指标。本文通过四平市环城一级公路沥青混凝土路面施工实践,从施工技术角度上对影响路面平整度的各种因素进行了分析,采取了哪些相应措施来控制路面平整度。     

Stochastic model specification search for Gaussian and partial non-Gaussian state space models

Model specification for state space models is a difficult task as one has to decide which components to include in the model and to specify whether these components are fixed or time-varying. To this aim a new model space MCMC method is developed in this paper. It is based on extending the Bayesian variable selection approach which is usually applied to variable selection in regression models to state space models. For non-Gaussian state space models stochastic model search MCMC makes use of auxiliary mixture sampling. We focus on structural time series models including seasonal components, trend or intervention. The method is applied to various well-known time series.     

Bayesian semiparametric stochastic volatility modeling

This paper extends the existing fully parametric Bayesian literature on stochastic volatility to allow for more general return distributions. Instead of specifying a particular distribution for the return innovation, nonparametric Bayesian methods are used to flexibly model the skewness and kurtosis of the distribution while the dynamics of volatility continue to be modeled with a parametric structure. Our semiparametric Bayesian approach provides a full characterization of parametric and distributional uncertainty. A Markov chain Monte Carlo sampling approach to estimation is presented with theoretical and computational issues for simulation from the posterior predictive distributions. An empirical example compares the new model to standard parametric stochastic volatility models.     

浅谈沥青混凝土路面产生不平整的原因及应对措施

沥青混凝土路面使用过程中出现了不同程度的接缝错台、波浪、坑槽、车辙等路面的不平整现象,结合工程实践经验分析了沥青混凝土路面产生不平整的原因,并且提出了相应的应对措施。     

沥青混凝土路面就地热再生的优势

沥青混凝土路面就地热再生的第一个优势就是其环保功能。在对环境要求日益严格的今天,大量的道路需要养护维修。采用再生技术,一方面我们不需要从自然界开采大量的砂、石、沥青等原材料;另一方面不向自然界倾倒大量的废沥青混合料。沥青混合料是有毒物质,靠自然分解时间极长,将对环境造成极大的影响。