土壤源热泵在合肥地区规模化应用绩效研究

介绍了土壤源热泵的工作原理,探讨了土壤源热泵空调应用于中央空调系统的设计方法,以及其主要部件地热换热器的埋管方式、结构、管材、运行等特点。选取几种常用的冷热源系统与土壤源热泵系统进行比较,参考合肥地区的能源价格,计算各方案的运行成本,用动态费用年值法评价了各方案的经济性。最后,对土壤源热泵系统的节能减排量进行了分析。     

企业选择SaaS 供应商的决策及实例研究

选择合适的SaaS供应商是很多企业信息化顺利进行的保障．本文建立了合理的SaaS供应商选择评价指标体系及SaaS供应商选择的多层次评估模型,阐述了基于层次分析法综合评估SaaS供应商的过程,并将该方法应用于某一企业,选择出了恰当的SaaS供应商．     

1000MW超超临界水冷和空冷机组生命周期评价

以1000 MW超超临界水冷和空冷燃煤机组为研究对象,采用生命周期分析方法,建立超超临界水冷和空冷电厂生命周期清单,从能源消耗、环境影响、经济性和综合评价指标进行对比分析。结果表明:空冷电厂较水冷电厂在全生命周期内节水3.08×10~8 m~3,水冷电厂生命周期综合评价指标值较空冷电厂低11.7%,缺水地区发展空冷电厂还需要技术和政策的支持。     

风力机叶片21%相对厚度翼型粗糙敏感性研究

基于变速变桨水平轴风力机,依据动量叶素理论和风力机实例,分析得出了叶片外侧翼型(包括21%相对厚度翼型)在低于额定风速变速运行阶段的粗糙敏感性评价指标为升力系数和升阻比的下降率;提出了根据升、阻力系数对输出功率的作用大小来确定两粗糙敏感性评价指标权重系数的方法,并用实例演示了21%相对厚度翼型粗糙敏感性评判基准的获得;另外,通过正交设计、XFOIL软件几何造型与气动计算和方差分析得出了翼型各几何参数在不同雷诺数下对粗糙敏感性不同评价指标的影响程度和最优组合是不一样的。本文结论可为不同风况下风力机翼型的设计和粗糙敏感性评价提供参考。     

Evaluating fitness by integrating the highest payoff within the neighborhood promotes cooperation in social dilemmas

In this paper, we propose a modified fitness evaluation mechanism, which integrates the environmental factors into the focal player’s fitness calculation, to investigate the evolution of cooperative behaviors in the prisoner’s dilemma game. Here, the fitness of a player is computed by combining the individual raw payoff and the highest payoff within the neighborhood, which is regulated by a single parameter termed as trust level η$\eta$. We show, compared to the traditional version (η=0$\eta =0$), that the cooperation level can be highly enhanced for η>0$\eta >0$. Meanwhile, we illustrate the dynamical evolution of cooperators on the square lattice, and for different defection parameters b$b$ the _FC−K$F_C-K$ curves are utilized to investigate the impact of noise during the strategy updates. Likely, the role of pursuing the highest payoff within the neighborhood also favors the survival of cooperators in the spatial snowdrift game. In addition, the sensibility of knowing the external factors is often not identical for all individuals and we consider the distributed trust level in which η$\eta$ is a distributed parameter, and the results indicate that pursuing the highest payoff in the neighborhood is also inspiring as a consequence of its positive effect on cooperation. The current results are highly instructive for us to further understand the maintenance and emergence of cooperation under the framework of evolutionary game theory.     

Guided plate wave scattering at vertical stiffeners and its effect on source location

This paper examines guided wave transmission characteristics of plate stiffeners and their influence on the performance of acoustic noise source location. The motivation for this work is the detection of air leaks in manned spacecraft. The leaking air is turbulent and generates noise that can be detected by a contact-coupled acoustic array to perform source location and find the air leak. Transmission characteristics of individual integral stiffeners are measured across a frequency range of 50-400 kHz for both high and low aspect-ratio rectangular stiffeners, and comparisons are made to model predictions which display generally good agreement. It is demonstrated that operating in frequency ranges of high plate wave stiffener transmission significantly improves the reliability of noise source location in the plate. A protocol is presented to enable the selection of an optimal frequency range for leak location.     

The mass transfer process and the growth rate of NaCl crystal growth by evaporation based on temporal phase evaluation

The mass transfer process and the crystal growth rate have been proved to be very important in the study of crystal growth kinetics, which influence the crystal quality and morphological stability. In this paper, a new method based on temporal phase evaluation was presented to characterize the mass transfer process in situ and determine the crystal growth rate. The crystallization process of NaCl crystal growth by evaporation was monitored in situ by a Mach-Zehnder interferometer, and the absolute concentration evolution, the evaporation rate and the real-time supersaturation of solution were obtained using temporal phase analysis, which acted as a novel technique to extract phase variation along time axis recently. Based on the evaporation rate and the absolution concentration, a new method to calculate mass transfer flux during the crystal growth without the knowledge of the mass transfer coefficient was proposed, and then the crystal growth rate could also be retrieved under the hypothesis of cubic crystals. The results show that the crystal growth rate increases with the supersaturation linearly. It is in agreement with the diffusion theories, which presume that matter is deposited continuously on a crystal face at a rate proportional to the difference in concentration between the points of deposition and the bulk of solution. The method is applicable to the research of crystallization process based on evaporation or vapor diffusion of which the precise conditions of nucleation and supersaturation are usually unknown because of the complexity of the evaporation rate and crystal growth rate.     

太湖地区全沉积物毒性识别评估研究

本研究用淡水单孔蚓（Monopylephorus limosus）和铜锈环棱螺（Bellamya aeruginosa）作为受试生物,对太湖沉积物的毒性进行筛查,采用全沉积物毒性识别评估（TIE）技术描述和鉴定太湖沉积物的主要毒性来源（重金属、氨氮或非极性有机物）．通过初始毒性实验筛选出4个对铜锈环棱螺具有毒性和1个对淡水单孔蚓具有毒性的沉积物样点．通过TIE,对于铜锈环棱螺,高风险点T6的毒性来源是非极性有机物和重金属;对于淡水单孔蚓,高风险点T12的毒性来源是非极性有机物、氨氮、重金属．T6和T12中4种多环芳烃（苯并[b＋k]荧葸、苊、二氢苊、茚并[1,2,3．cd]芘）是非极性有机物中产生生物毒性的来源之一,而Pb是T6和T12中产生毒性的主要重金属．     

基于VaR-Copula的信息安全评价模型研究

近年来,我国信息安全面临的形势越来越严峻,而作为信息安全风险防范的最基础手段——风险评价理论和方法还没有得到有效发展和真正发挥作用.研究在深入分析信息安全风险理论基础上,采用VaR理论和Copula法,构建了一种信息安全评价模型,得到了从整体上来把握和衡量信息安全的VaR指标,解决了现有研究主要集中于构建指标体系及其基础上评价模型的弊端.最后,并采用实例验证了该模型的有效性.     

基于模糊理论的产后大出血风险预测

运用模糊综合评判的方法对孕产妇产后大出血的风险进行预测评估.依据大量产后出血的医学资料,建立了合适的评价指标体系,利用改进的层次分析法确定权重集,构造出隶属函数,得到单因素评判矩阵.依据产后大出血的临床医学特点,设计了一个动态的评判系统,根据每个病人的个体情况进行综合评判,预测出发生产后出血的风险等级,并给出引起出血的可能原因.通过对大量病例测试表明,该系统评判结果与临床诊断相一致,从而验证了理论的正确性和实用性.