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41.
针对智慧制造评估时专家的决策信息具有犹豫模糊不确定性问题,提出了一种关于准则具有犹豫模糊偏好关系的改进交互式多准则决策(TODIM)方法。首先提出了准则间的犹豫模糊偏好关系概念,并证明了其基本性质。在TODIM方法优势度的计算过程中,将准则权重犹豫模糊偏好关系替代原有的精确值权重,使信息的准确性最大化。将该方法用于智能制造的评估上,实例分析结果表明所提方法是可行和有效的。 相似文献
42.
为分析不同沉积与成岩作用改造下致密砂岩储层的孔喉类型及其参数差异,利用物性、铸体薄片、扫描电镜、恒速压汞、图像粒度与X衍射实验结果,对比了鄂尔多斯盆地合水地区延长组长8储层和薛岔地区延长组长6储层的孔喉类型,定量评价了孔喉参数,揭示了形成原因。结果表明,合水地区长8储层孔隙更为发育,粒间孔、溶蚀孔、晶间孔和微孔、弱压实成因缩颈状喉道和溶蚀成因、粘土胶结成因管束状喉道含量高;薛岔地区长6储层的孔隙类型少且发育程度较差,压实成因片状、弯片状喉道含量高。两个区块的孔隙参数差异小,喉道参数差异大,前者大喉道更为发育,喉道差异大,孔喉比大,对渗透率起贡献的喉道分布范围更宽。相同渗透率条件下,前者的平均喉道半径、主流喉道半径和孔喉比大于后者。沉积水动力条件、粒度、碎屑组分、填隙物、成岩作用类型及其改造程度是两个研究区孔隙发育程度不同、喉道类型差异和孔喉参数表现出不同特征的主要原因。 相似文献
43.
44.
Package design influences consumers’ expectations of a product’s sensory properties and expected healthiness and/or tastiness, and potentially also changes actual product perception during consumption. The robustness of these effects is far from clear, however. This study investigated the influence of package cues signalling either hedonic or healthy product properties on expectations and subsequent product evaluation over repeated consumption.In a between-subjects design, 92 participants evaluated product expectations and taste perceptions of a chocolate-sesame flavoured biscuit with a package emphasizing either its healthy (n = 44) or hedonic (n = 48) aspects, both at a central location (CLT) and during six home use tests (HUT), using both explicit (questionnaires) and implicit (IAT) measures.Package design significantly affected (p < 0.05) consumers’ expectations of the product. They expected the biscuit to be tastier, less attractive and less healthy in the hedonic package condition, and less tasty, more attractive and healthier in the healthy package condition. However, these effects did not transfer to actual product evaluations upon tasting, either blind or tasting in combination with viewing the package during the HUTs. Implicit attitudes did change as a result of repeated exposures, depending on the package consumers were provided with, indicating product-package interactions over time (p < 0.05).In conclusion, package design influences product expectations and associations with its healthiness and attractiveness, which is of relevance in product choice and purchase settings. However, at the stage of (repeated) consumption, intrinsic (sensory) properties become the dominant drivers of products’ sensory and hedonic evaluations, and the impact of package cues seems less potent. 相似文献
45.
In recent years, the Industry 4.0 concept brings new demands and trends in different areas; one of them is distributing computational power to the cloud. This concept also introduced the Reference Architectural Model for Industry 4.0 (RAMI 4.0). The efficiency of data communications within the RAMI 4.0 model is a critical issue. Aiming to evaluate the efficiency of data communication in the Cloud Based Cyber-Physical Systems (CB-CPS), this study analyzes the periods and data amount required to communicate with individual hierarchy levels of the RAMI 4.0 model. The evaluation of the network properties of the communication protocols eligible for CB-CPS is presented. The network properties to different cloud providers and data centers’ locations have been measured and interpreted. To test the findings, an architecture for cloud control of laboratory model was proposed. It was found that the time of the day; the day of the week; and data center utilization have a negligible impact on latency. The most significant impact lies in the data center distance and the speed of the communication channel. Moreover, the communication protocol also has impact on the latency. The feasibility of controlling each level of RAMI 4.0 through cloud services was investigated. Experimental results showed that control is possible in many solutions, but these solutions mostly cannot depend just on cloud services. The intelligence on the edge of the network will play a significant role. The main contribution is a thorough evaluation of different cloud providers, locations, and communication protocols to provide recommendations sufficient for different levels of the RAMI 4.0 architecture. 相似文献
46.
中子管是一种用途广泛的关键部件,然而目前国产中子管的可靠性水平与国外相比还有一定差距,难以满足各行业的使用需求。本文分析了中子管的主要故障模式,采用模糊综合评判和层次分析法对中子管故障进行了多级模糊综合评判,并对中子管故障风险进行了评估。结果表明,中子管总体故障风险水平中等,故障风险前3位的部件为靶、氘氚储存器和加速极,在设计和使用中应重点关注靶释放氦气,靶膜氧化,氘氚储存器吸气剂局部破损,绝缘瓷管破损,加速极离子加速、聚焦不稳定等故障。 相似文献
47.
Customer-involved design concept evaluation (DCE) allows customers to take part in evaluating the design alternatives to get more popular design concept. Traditional customer-involved DCE methods still focus on the collection of customer responses and only consider cost and benefit characteristics of design criteria in multi-criteria decision-making (MCDM) based evaluation process. Few studies have customized the decision-making algorithms specifically aimed at customers’ preferences. This paper further explores the customers’ influences in the early stages of the product design development, and proposes a new rough number based MCDM model (i.e., VIKOR) incorporating customers’ preferences for design specifications along with designers’ perceptions for the characteristics of design criteria (cost and benefit) to perform concept evaluation under subjective environment, and this proposed method is named as integrated rough VIKOR (IR-VIKOR). The objective of this study is to identify the best design concept which maximizes the satisfactions of expectations from most customers as well as conforms to the characteristics of design criteria. Firstly, Shannon entropy is used to obtain the weightings and relative importance ratings of design criteria from the customers’ preferences. Secondly, the customers’ preferences for design attribute values, the importance ratings of design criteria and the characteristics of design criteria are combined together to define the ideal solutions to calculate the rough evaluation index of each design alternative in IR-VIKOR, and finally the ranking result is provided by IR-VIKOR to determine the best design concept. A practical design example is introduced to illustrate the evaluation process of this proposed method, and the empirical comparisons are further carried out to validate its superiority for DCE. Through the sensitivity analysis experiments including i) inside IR-VIKOR, and ii) between IR-VIKOR and other classical MCDM methods, the proposed method is proved to be a reliable and feasible customer-involved DCE approach. 相似文献
48.
环境污染治理投资是生态环境保护的资金来源,其投资规模和投资形式对生态效率产生着重大影响。本文构建生态效率测度指标和非期望的超效率SBM模型,测定了长江经济带9省2市的生态效率水平,再利用Tobit模型量化研究环境污染治理投资的总量及各投资形式对生态效率的影响程度,得出长江经济带环境污染治理投资对生态效率具有正向影响但影响程度一般,3种环境污染治理投资类型中的当年完成环保验收项目环保投资对生态效率影响程度最大且显著。 相似文献
49.
不同熄焦方式对焦炭的冷态强度、热态强度以及生产焦炉的工艺特点均有影响,为了更好地指导40 kg试验焦炉的生产,需对比分析水熄焦、干熄焦方式对焦炭质量的影响。选用4种不同炼焦煤和1种生产配合煤,利用40 kg级实验焦炉炼制焦炭,分别采用蒸汽熄焦与水熄焦方式对40 kg焦炉炼制的焦炭进行冷却,检测熄焦后焦炭的工业分析、机械强度及热性质等性能指标,对比分析2种熄焦方式对焦炭质量的影响,并研究2种熄焦方式下焦炭与生产干熄焦的焦炭质量关系。结果表明,相对水熄焦,蒸汽熄焦的焦炭水分较稳定(小于1%)、成焦率有所提升,改善了焦炭质量,其中1/3焦煤冷强度的改善最为明显,气煤与1/3焦煤的热性质改善最为明显,肥煤的成焦率提升最大;蒸汽熄焦与生产干熄焦的焦炭质量指标更接近,机械强度M 40一致、M 10数据高出2.5个百分点,热性质CRI数据高出8.1个百分点、CSR低出10.4个百分点。焦化企业可参照试验结果,进一步优化40 kg实验焦炉熄焦工艺及调整生产与试验焦炉的相关性。 相似文献
50.