Evolutionary inference for function-valued traits: Gaussian process regression on phylogenies

Biological data objects often have both of the following features: (i) they are functions rather than single numbers or vectors, and (ii) they are correlated owing to phylogenetic relationships. In this paper, we give a flexible statistical model for such data, by combining assumptions from phylogenetics with Gaussian processes. We describe its use as a non-parametric Bayesian prior distribution, both for prediction (placing posterior distributions on ancestral functions) and model selection (comparing rates of evolution across a phylogeny, or identifying the most likely phylogenies consistent with the observed data). Our work is integrative, extending the popular phylogenetic Brownian motion and Ornstein–Uhlenbeck models to functional data and Bayesian inference, and extending Gaussian process regression to phylogenies. We provide a brief illustration of the application of our method.     

Applications of percolation theory to fungal spread with synergy

There is increasing interest in the use of the percolation paradigm to analyse and predict the progress of disease spreading in spatially structured populations of animals and plants. The wider utility of the approach has been limited, however, by several restrictive assumptions, foremost of which is a strict requirement for simple nearest-neighbour transmission, in which the disease history of an individual is influenced only by that of its neighbours. In a recent paper, the percolation paradigm has been generalized to incorporate synergistic interactions in host infectivity and susceptibility, and the impact of these interactions on the invasive dynamics of an epidemic has been demonstrated. In the current paper, we elicit evidence that such synergistic interactions may underlie transmission dynamics in real-world systems by first formulating a model for the spread of a ubiquitous parasitic and saprotrophic fungus through replicated populations of nutrient sites and subsequently fitting and testing the model using data from experimental microcosms. Using Bayesian computational methods for model fitting, we demonstrate that synergistic interactions are necessary to explain the dynamics observed in the replicate experiments. The broader implications of this work in identifying disease-control strategies that deflect epidemics from invasive to non-invasive regimes are discussed.     

青藏±400 kV格尔木换流站户内直流场厂房屋面结构型式论证

通过对格尔木±400 kV换流站工程中户内直流场厂房屋面采用不同的结构型式，从结构受力、造价预算和施工工期等方面的分析比较，提出经济可行的屋面结构型式，为同行进行类似设计时提供参考。     

新疆小型水库工程大坝设计要点

本文围绕新疆建设一批定居兴牧水源工程的小型水库工程的前期大坝设计,重点对坝型选择、坝体结构设计、基础处理等问题进行了讨论。从地形、地质条件和填筑材料等方面考虑,大多数水库工程均选择当地材料坝,主要坝型有沥青混凝土心墙坝和混凝土面板堆石坝。针对混凝土面板堆石坝设计,基于填筑料的选择和渗透系数条件提出:坝体内可取消过渡层及竖向排水及水平排水设施;沥青混凝土心墙坝施工速度快,适宜新疆的气候条件。     

A Bayesian analysis of spherical pattern based on finite Langevin mixture

Parameter estimation is a cornerstone of most fundamental problems of statistical research and practice. In particular, finite mixture models have long been heavily relied on deterministic approaches such as expectation maximization (EM). Despite their successful utilization in wide spectrum of areas, they have inclined to converge to local solutions. An alternative approach is the adoption of Bayesian inference that naturally addresses data uncertainty while ensuring good generalization. To this end, in this paper we propose a fully Bayesian approach for Langevin mixture model estimation and selection via MCMC algorithm based on Gibbs sampler, Metropolis–Hastings and Bayes factors. We demonstrate the effectiveness and the merits of the proposed learning framework through synthetic data and challenging applications involving topic detection and tracking and image categorization.     

合理的摇床选型及选别工艺可以获得较理想的选别指标

从某粗锡精矿精选系统重选部分的生产情况分析人手，提出了该精选系统重选部分存在的主要问题：一是摇床选型不合理，二是重选的选别工艺存在一定的问题。针对存在的问题，对精选系统重选部分进行了简单的改造，获得了较理想的选别指标。改造后与改选前相比，锡精矿含锡提高了3．12个百分点，锡回收率提高了lO．64个百分点。     

装卸用直臂架多用途门机典型起升钢丝绳卷绕系统的分析与比较

通过详细地分析和比较已被上海振华重工(ZPMC)完成项目中3种典型的装卸用直臂架多用途门机的起升钢丝绳卷绕形式,总结出每种卷绕形式的特点和各自的适用条件,对今后提高装卸用直臂架门机的设计和制造的综合质量具有一定的指导意义。     

升压水泵房肘型流道结构分析及主筋选配

本文首先运用SolidWorks软件对某升压水泵房的蜗壳和肘型引水流道结构进行三维整体建模；其次，采用ANSYS软件对模型进行网格剖分及有限元方法分析；最后，针对肘型引水流道结构的计算结果，对该结构进行了主筋选配设计。     

VO2 nanostructures based chemiresistors for low power energy consumption hydrogen sensing

Mott-type VO₂ oxide nanobelts are demonstrated to be effective hydrogen gas sensors at room temperature. These nanobelts, synthesized by hydrothermal process and exhibiting the VO₂ (A) crystallographic phase, display room temperature H₂ sensitivity as low as 0.17 ppm. The nanobelts (ultralong belt-like) nanostructures could be an ideal system for fully understanding dimensionally confined transport phenomena in functional oxides and for building functional devices based on individual nanobelts.