Development and application of a holistic model for the steady state growth of porous anodic alumina films

A holistic model was developed and applied to anodic alumina films galvanostatically grown in sulphuric acid solution at different anodising conditions thus characterised by different structural characteristics. The O²⁻ and Al³⁺ species transport numbers near the metal|oxide interface were determined that depended on both temperature and current density. The rate of film thickness growth was found to be proportional to the O²⁻ anionic current through the barrier layer near the metal|oxide interface. The results introduced a new growth mechanism theory embracing the rarefaction of barrier layer oxide lattice towards the metal|oxide interface. The oxide density near the metal|oxide is closely independent of anodising conditions and is related to the transformation of Al lattice to a transient oxide lattice about 37% rarer than that of γ-Al₂O₃ that is further suitably transformed to denser, amorphous or nanocrystalline material as this oxide is shifted to the oxide|electrolyte interface and becomes the pore wall material. This gradual lattice density variability can explain many peculiar properties of anodic alumina films.     

亚热带中学校园设计与探索——以厦门六中高中部扩建工程为例

我国东南部地区以亚热带气候为主,其典型的“夏热冬暖”、高湿、日照充足的气候特征是亚热带中学校园设计的出发点。本文立足于把亚热带中学校园构筑成一个与大自然共生的适宜学生群聚的生活与学习场所,以厦门六中高中部扩建工程规划与建筑方案设计为例,从总体规划、建筑单体、景观绿化三个方面出发,探讨了亚热带中学校园所应具备的设计元素和架构方式。     

高原气候条件下的西藏传统民居生态经验和盲点

以高原气候为出发点,首先分析和总结西藏传统民居在单体布局、阳光利用、居民生活模式的生态经验;进而从被动式太阳能利用的角度,批判性地提出西藏传统民居生态"盲点",并提出相应的改进建议.     

Modelling indoor air and hygrothermal wall interaction in building simulation: Comparison between CFD and a well-mixed zonal model

Traditional models for heat and moisture transport in buildings consider indoor air as a well-mixed gas with uniform properties. Computational fluid dynamics (CFD) offers the possibility of taking into account the effect of air distributions on the interaction with the walls. This paper compares simulations made with a traditional well-mixed model and a CFD model in search for the limitations of the well-mixed model. The possibility of improving the accuracy of the well-mixed results by using CFD generated surface transfer coefficients is investigated. To allow for a good comparison between both models the CFD model is extended with an effective penetration depth (EPD) model for the moisture buffering in the walls, an approach which is also used in the well-mixed model. The average indoor climate and the average relative humidity in the walls predicted by the CFD–EPD model and the well-mixed model with standard surface transfer coefficients agree quite well for the studied test case. The use of CFD generated surface transfer coefficients in the well-mixed model was able to improve the well-mixed results significantly in case a stable and physically relevant surface transfer coefficient could be related to the average indoor air conditions. The studied case showed that this is not always guaranteed.     

Severn Barrage tidal power project: implications for carbon emissions

UK Government encouragement of the Severn Barrage project has regard for the fact that this is by far the largest single source of renewable energy available to the United Kingdom. A major concern for all forms of electricity generation is their effects of carbon emissions and, as a result which is now generally recognised, on global warming. The present paper makes use of published sources of carbon emissions data to estimate the carbon content of each of the operations required to produce, transport, construct, operate and decommission this barrage if it is located and designed as set out in 1989. The approach adopted here is based on estimating the ratio of the life-cycle carbon emissions demand of the scheme (gCO₂) relative to its energy output (kW) over an assumed lifetime, this to include expected plant replacements over that period.     

Psychosocial safety climate moderates the job demand–resource interaction in predicting workgroup distress

Psychosocial safety climate (PSC) arises from workplace policies, practices, and procedures for the protection of worker psychological health and safety that are largely driven by management. Many work stress theories are based on the fundamental interaction hypothesis – that a high level of job demands (D) will lead to psychological distress and that this relationship will be offset when there are high job resources (R). However we proposed that this interaction really depends on the organizational context; in particular high levels of psychosocial safety climate will enable the safe utilization of resources to reduce demands. The study sample consisted of police constables from 23 police units (stations) with longitudinal survey responses at two time points separated by 14 months (Time 1, N = 319, Time 2, N = 139). We used hierarchical linear modeling to assess the effect of the proposed three-way interaction term (PSC × D × R) on change in workgroup distress variance over time. Specifically we confirmed the interaction between emotional demands and emotional resources (assessed at the individual level), in the context of unit psychosocial safety climate (aggregated individual data). As predicted, high emotional resources moderated the positive relationship between emotional demands and change in workgroup distress but only when there were high levels of unit psychosocial safety climate. Results were confirmed using a split-sample analysis. Results support psychosocial safety climate as a property of the organization and a target for higher order controls for reducing work stress. The ‘right’ climate enables resources to do their job.     

On Proper Choice of Variability Control Chart for Normal and Non‐normal Processes

Control charts are an important statistical process control tool used to monitor changes in process location and variability. This study addresses issues regarding the proper choice of control chart for efficient monitoring of process variability. The choice of the best estimator to be used for variability charts has not been made clear in literature. We have analyzed the performance of eight control chart structures, based on different estimates of process standard deviation. The performance of control charts is investigated under the existence and violation of ideal assumptions of normality. Control chart constants and factors required for computing probability limits, considering normal and different non‐normal parent distributions, are provided for all variability charts. This study aims at providing guidance to quality practitioners in choosing the appropriate variability control chart for normal and non‐normal processes. Copyright © 2011 John Wiley & Sons, Ltd.     

应对气候变化为我们带来的机遇

叙述了应对气候变化给我们带来转型发展的机遇,提出,借应对气候变化的机遇,可以完善国家基础设施的建设,带动国家基础研究的进步,推动创新型国家的建设。     

The Cladistic Basis for the Phylogenetic Diversity (PD) Measure Links Evolutionary Features to Environmental Gradients and Supports Broad Applications of Microbial Ecology��s ��Phylogenetic Beta Diversity�� Framework

The PD measure of phylogenetic diversity interprets branch lengths cladistically to make inferences about feature diversity. PD calculations extend conventional species-level ecological indices to the features level. The “phylogenetic beta diversity” framework developed by microbial ecologists calculates PD-dissimilarities between community localities. Interpretation of these PD-dissimilarities at the feature level explains the framework’s success in producing ordinations revealing environmental gradients. An example gradients space using PD-dissimilarities illustrates how evolutionary features form unimodal response patterns to gradients. This features model supports new application of existing species-level methods that are robust to unimodal responses, plus novel applications relating to climate change, commercial products discovery, and community assembly.     

以住宅为例谈建筑设计的可变形态及其实现

从应用价值的角度对建筑的可变性进行了分析,阐述了住宅建筑可变性设计的必要性及设计理念,同时提出了可变性设计的实现途径,指出可变住宅不单实现了建成前的灵活可变性,建成后还可结合实际需求,在不影响原有结构的前提下灵活变动,从而为人们提供了一种全新的居住模式。