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71.
Space heating accounts for almost 60% of the energy delivered to housing which in turn accounts for nearly 27% of the total UK's carbon emissions. This study was conducted to investigate the influence of heating control design on the degree of ‘user exclusion’. This was calculated using the Design Exclusion Calculator, developed by the Engineering Design Centre at the University of Cambridge. To elucidate the capability requirements of the system, a detailed hierarchical task analysis was produced, due to the complexity of the overall task. The Exclusion Calculation found that the current design placed excessive demands upon the capabilities of at least 9.5% of the UK population over 16 years old, particularly in terms of ‘vision’, ‘thinking’ and ‘dexterity’ requirements. This increased to 20.7% for users over 60 years old. The method does not account for the level of numeracy and literacy and so the true exclusion may be higher. Usability testing was conducted to help validate the results which indicated that 66% of users at a low-carbon housing development could not programme their controls as desired. Therefore, more detailed analysis of the cognitive demands placed upon the users is required to understand where problems within the programming process occur. Further research focusing on this cognitive interaction will work towards a solution that may allow users to behave easily in a more sustainable manner.  相似文献   
72.
黄时达 《四川环境》1992,11(3):7-13
本文通过对四川省环境特点的分析与环境科技工作的回顾,提出四川省环境科技研究方向与任务的建议,与环境科技管理及研究人员共同研讨。  相似文献   
73.
范爽  艾兆春 《环境技术》2014,(2):33-35,57
通过三坐标测量仪对机械加工零件的外锥和内锥进行测量分析。对一些通用量具无法测量的角度提供准确的数值。利用不确定度评定标准公式计算出三坐标测量角度的不确定度分析。经过三坐标测量仪的先进技术改变现代通用量具的测量方法,提高通用量具无法达到的高精度测量时代,为高精度测量提供了一种新的测量手段。  相似文献   
74.
在火灾等紧急情况下,可见度较低时的行人疏散与正常时的疏散情况有明显的区 别。基于前人成果的基础上,通过引入从众效应阐述了可见度较低时的元胞自动机疏散 理论模型,并定义区分了普遍性从众、理性从众和盲目从众。研究结果表明:理性从众 对疏散能够起到良好的优化作用;盲目从众对疏散的作用效果具有不可预测性,在某些 情况下盲目从众甚至会对疏散起到严重阻碍的作用。因此,建议在条件允许的条件下积 极采用理性从众的行为方式,尽量避免采用盲目从众。研究还发现,理性从众对疏散的 优化效果基本不受初始行人数量、出口宽度和可视距离的影响。  相似文献   
75.
基于资源场势的我国煤炭空间配置特征研究   总被引:3,自引:1,他引:2  
论文将资源场势的理论运用到煤炭资源领域,利用相关公式计算全国可获得数据的30个省(区、市)的煤炭资源势、煤炭作业势和煤炭资源-作业势,分析了1986年以来我国煤炭资源空间配置的基本特征,并采用煤炭配置质量指数评价我国区域煤炭资源空间配置的合理性。研究表明:①随着时间的变化,我国煤炭资源场趋于集中,空间上呈现出以晋豫地区为中心,从东北向西北偏移的趋势;②各地区煤炭作业势在时间上变化幅度较小,空间上与煤炭资源势呈现总体相近的格局;③我国煤炭资源-作业场有向东部南部沿海地区和晋陕蒙地区集聚的趋势,目前基本形成了以东部南部沿海地区、环渤海地区为主的"S"形输入区和以晋陕蒙为主的"V"形输出区的空间格局;④可以将我国划分为三种煤炭空间配置类型区,即场源区(6个)、场汇区(19个)和基本平衡区(5个),煤炭资源空间配置具有显著的区域差异,空间极化现象突出;⑤我国煤炭资源空间配置总体是合理的,但是个别地区的配置方向或配置力度不尽合理,存在输出区过度输出和输入区过量输入等情况。  相似文献   
76.
近年来,随着污染防治攻坚战的不断强化,京津冀及周边地区重污染天气问题初步得到缓解.为了深度改善大气环境质量,落实精准治污,更好地服务于京津冀有毒有毒大气污染物的环境管理,开展了京津冀及周边地区优先控制有毒有害大气污染物名录的研究.以京津冀及周边地区为主要研究对象,采用文献调研法建立备选名单;针对备选名单中的有毒有害大气污染物进行危害信息收集,采用两步筛选法,以危害筛选指标、暴露筛选指标、持久性/生物蓄积性筛选指标共包含10项内容进行赋分求和,筛选出高分值的污染物建立候选名单;在候选名单基础上,从国家排放标准、地方排放标准、监测方法三方面进行筛选,形成优控名录.筛选形成的优控名录包括苯、环氧乙烷、二英类、砷及其化合物、铅及其化合物、甲醛、氯乙烯、三氯乙烯、1,2-二氯丙烷、氯甲基甲醚、铍及其化合物、三氯甲烷在内的12种(类)污染物,可为“十四五”有毒有害大气污染物环境管理及今后京津冀优控名录的公布提供研究基础.   相似文献   
77.
煤矿企业员工在生产和安全方面的能力决定了其产出水平与所需的成本,从而对企业的激励措施产生影响。因此,在考虑到员工能力的基础上,利用委托代理的相关理论分析员工在生产和安全方面的能力对企业激励措施的影响。研究发现:在最优的情况下,员工的产出水平与奖励系数成正相关关系,成本系数与奖励系数负相关。任务的高产出水平会使该任务具有较高的吸引力。员工某项任务的产出水平与员工在该项任务上付出的努力是同方向变化的。单纯依靠员工的能力对安全状况的改善是有限的,需要企业采取措施,提高安全的产出水平。  相似文献   
78.
陆楠  魏斌  朱琦  刘定  杨毅 《中国环境管理》2015,7(6):66-70,83
区域大气污染防治管理系统是生态环境保护信息化工程(《"十二五"国家政务信息化工程建设规划》中规划的国家级信息系统之一)项目建设的重要内容之一.本文对区域大气污染防治管理系统的建设需求进行了分析,系统针对大尺度的区域性大气环境质量问题,紧密结合国务院"大气污染防治行动计划"的目标任务要求,开展数据调度与综合分析等功能的建设,旨在通过数据分析提高重点区域大气环境质量状况与污染成因的评估能力,通过情景模拟与模型运算为区域大气污染治理措施的制定与动态调整提供定量化数据支持.系统的建设与实施将有望成为国家大气污染防治领域跨部门数据共享与交换的基础工程,为区域大气污染防治工作提供有力的信息化技术支撑.  相似文献   
79.
Objectives: There are 3 standardized versions of the Detection Response Task (DRT), 2 using visual stimuli (remote DRT and head-mounted DRT) and one using tactile stimuli. In this article, we present a study that proposes and validates a type of auditory signal to be used as DRT stimulus and evaluate the proposed auditory version of this method by comparing it with the standardized visual and tactile version.

Methods: This was a within-subject design study performed in a driving simulator with 24 participants. Each participant performed 8 2-min-long driving sessions in which they had to perform 3 different tasks: driving, answering to DRT stimuli, and performing a cognitive task (n-back task). Presence of additional cognitive load and type of DRT stimuli were defined as independent variables. DRT response times and hit rates, n-back task performance, and pupil size were observed as dependent variables.

Results: Significant changes in pupil size for trials with a cognitive task compared to trials without showed that cognitive load was induced properly. Each DRT version showed a significant increase in response times and a decrease in hit rates for trials with a secondary cognitive task compared to trials without. Similar and significantly better results in differences in response times and hit rates were obtained for the auditory and tactile version compared to the visual version. There were no significant differences in performance rate between the trials without DRT stimuli compared to trials with and among the trials with different DRT stimuli modalities.

Conclusions: The results from this study show that the auditory DRT version, using the signal implementation suggested in this article, is sensitive to the effects of cognitive load on driver's attention and is significantly better than the remote visual and tactile version for auditory–vocal cognitive (n-back) secondary tasks.  相似文献   

80.
Red lists are a crucial tool for the management of threatened species and ecosystems. Among the information red lists provide, the threats affecting the listed species or ecosystem, such as pollution or hunting, are of special relevance. This information can be used to quantify the relative contribution of different threat factors to biodiversity loss by disaggregating the cumulative extinction risk across species into components that can be attributed to certain threats. We devised and compared 3 metrics that accomplish this and may be used as indicators. The first metric calculates the portion of the temporal change in red list index (RLI) values that is caused by each threat. The second metric attributes the deviation of an RLI value from its reference value to different threats. The third metric uses extinction probabilities that are inferred from red list categories to estimate the contribution of a threat to the expected loss of species or ecosystems within 50 years. We used data from Norwegian Red Lists to test and evaluate these metrics. The first metric captured only a minor portion of the biodiversity loss caused by threats because it ignores species whose red list category does not change. Management authorities will often be interested in the contribution of a given threat to the total deviation from the optimal state. This was measured by the remaining metrics. The second metric was best suited for comparisons across countries or taxonomic groups. The third metric conveyed the same information but uses numbers of species or ecosystem as its unit, which is likely more intuitive to lay people and may be preferred when communicating with stakeholders or the general public.  相似文献   
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