Effects of upholstery materials on the burning behavior of real‐scale residential upholstered furniture mock‐ups

Fire spread and growth on real‐scale four cushion mock‐ups of residential upholstered furniture (RUF) were investigated with the goal of identifying whether changes in five classes of materials (barrier, flexible polyurethane foam, polyester fiber wrap, upholstery fabric, and sewing thread), referred to as factors, resulted in statistically significant changes in burning behavior. A fractional factorial experimental design plus practical considerations yielded a test matrix with 20 material combinations. Experiments were repeated a minimum of two times. Measurements included fire spread rates derived from video recordings and heat release rates (HRRs). A total of 13 experimental parameters (3 based on the videos and 10 on the HRR results), referred to as responses, characterized the measurements. Statistical analyses based on Main Effects Plots (main effects) and Block Plots (main effects and factor interactions) were used. The results showed that three of the factors resulted in statistically significant effects on varying numbers of the 13 responses. The Barrier and Fabric factors had the strongest main effects with roughly comparable magnitudes. Foam was statistically significant for fewer of the responses and its overall strength was weaker than for Barrier and Fabric. No statistically significant main effects were identified for Wrap or Thread. Multiple two‐term interactions between factors were identified as being statistically significant. The Barrier*Fabric interaction resulted in the highest number of and strongest statistically significant effects. The existence of two‐term interactions means that it will be necessary to consider their effects in approaches designed to predict the burning behavior of RUF.     

Al、Mo含量对铸造钛合金力学性能的影响

运用正交实验 ,考察了Al、Mo含量对Ti Al Mo 1Zr系铸造钛合金力学性能的影响。试验结果表明 :随Al、Mo含量提高 ,铸造合金的强度增加 ,塑性和冲击韧性降低 ,但Al、Mo的交互作用却使合金塑性提高 ,强度和冲击韧性降低     

Numerical modeling of combustion processes and pollutant formations in direct-injection diesel engines

The Representative Interactive Flamelet (RIF) concept has been applied to numerically simulate the combustion processes and pollutant formation in the direct injection diesel engine. Due to the ability for interactively describing the transient behaviors of local flame structures with CFD solver, the RIF concept has the capabilities to predict the auto-ignition and subsequent flame propagation in the diesel engine combustion chamber as well as to effectively account for the detailed mechanisms of soot formation, NO_X formation including thermal NO path, prompt and nitrous NO_X formation, and reburning process. Special emphasis is given to the turbulent combustion model which properly accounts for vaporization effects on the mixture fraction fluctuations and the pdf model. The results of numerical modeling using the RIF concept are compared with experimental data and with numerical results of the commonly applied procedure which the low-temperature and high-temperature oxidation processes are represented by the Shell ignition model and the eddy dissipation model, respectively. Numerical results indicate that the RIF approach including the vaporization effect on turbulent spray combustion process successfully predicts the ignition delay time and location as well as the pollutant formation.     

企业施工定额的编制以及施工成本分析平台的应用

本文阐述了施工企业内部编制定额的必要性和成本分析平台的实用性,并根据多年的工作经验就建筑施工企业对施工成本的控制谈谈一自己的认识和看法.     

对企业账面利润与现金流量关系的认识

本文阐述了企业账面利润与现金流量的关系 ,指出了企业账面利润与现金流量的四个不同点 ,并且提出了一个现代企业应如何在四个方面做好工作 ,正确处理好这两者的关系。     

贯彻ISO9000标准的实践和体会

阐述了机械制造企业贯彻ISO9000标准的主要做法，指出了贯标是企业走向市场的重要战略措施。     

A theory of personalisation of appearance: quantitative evaluation of qualitatively derived data

Using qualitative data, Blom and Monk (2003) derived a theory of why people choose to personalise the appearance of their PCs and mobile phones. This paper describes some quantitative data that provide some support for, and some modifications to, the theory. Individuals having personal home pages were recruited to fill in a questionnaire that assesses dispositions to personalise and its effects. In addition the 82 home pages were inspected to assess the extent of personalisation. This correlated significantly with the dispositions 'Frequency of Use' and 'Knowledge of Personalisation'. The questionnaire items corresponding to effects were factor analysed. A four-factor solution suggested item groupings similar, but not identical, to those used in the theory. There are significant positive correlations between the extent of personalisation and cognitive effects and enduring emotional effects. The value of quantitative data for confirming and refining a qualitative theory is discussed.     

Possibilities and problems with the use of models as a communication tool in water resource management

Politicians and policy-makers, as well as modellers, often nurses an expectation that model derived results is an objective source of information that can be used to support decisions. However, several prerequisites have to be dealt with in order to ensure that models can be used as legitimate and efficient tools in water resource management. Based on empirical material from recent studies on the use of models in stakeholder dialogues, mainly focusing on catchment nutrient transport, two central problems are identified: (a) Models are laden with choices and thus depend on assumptions and priorities of modellers. (b) There are several factors that influence ability and willingness of stakeholders (as information recovers) to criticize or accept results of the modelling exercise. Recognized factors likely to influence stakeholders' acceptance of model derived results include issues at stake, stakeholders' ability to criticize model derived information, and their trust in the institutions that have developed or applied the used models. Identified prerequisites for successful use of models in integrated water resource management include: consideration of user relevance, awareness of and preparedness to handle constraints linked to communication of model-based results, transparency of used models and data and of involved uncertainties, mutual respect between experts and stakeholders and between involved stakeholder groups, a robust institutional network, and sufficient time for dialogues. Development and use of strategies for participatory modelling, based on a continuous dialogue between experts and stakeholders is recommended as a way to facilitate that the prerequisites for a successful use of models in water resource management are fulfilled.     

Formation of Azobenzenes and Azoxybenzenes from the Aqueous Reactions of Anilines and Ozone

Azobenzenes and azoxybenzenes are two of the products identified from the aqueous reaction of anilines with ozone. Aniline concentration and functional groups on the benzene ring of aniline affected the amount of azobenzenes and azoxybenzenes formed; (1) decreasing the aniline concentration significantly increased azobenzene formation, and (2) electron-withdrawing groups increased the formation of its related azobenzene and azoxybenzene, whereas electron-donating groups had the opposite effect.