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61.
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
62.
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
63.
64.
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
65.
Amorn Chaiyasat Sirinard Jearanai Lew P Christopher Md Nur Alam 《Polymer International》2019,68(1):102-109
A novel process for the production of superabsorbent materials (hydrogels) from bacterial cellulose (BC) was developed. Prior to crosslinking with a water‐soluble polyethylene glycol diacrylate (PEGDA), BC was first carboxymethylated and functionalized with glycidyl methacrylate. The degree of crosslinking influenced the swelling properties of the hydrogels. The use of greater amounts of PEGDA enhanced the formation of a thicker macromolecular network containing fewer capillary spaces in the crosslinked gel. The maximum water retention value of the hydrogels containing 2.5–3.5 mmol of carboxyl groups per gram of gel reached 125 g g?1 in distilled water, and 29 g g?1 in saline (0.9% NaCl solution). The highly porous hydrogel architecture with a pore size of 350–600 µm created a high specific surface area. This enables rapid mass penetration in superabsorbent applications. The superabsorbent hydrogels reached 80% of their maximum water absorption capacity in 30 min. © 2018 Society of Chemical Industry 相似文献
66.
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
67.
Elli Ntakou Ralph Masiello Farnaz Farzan Shay Bahramirad Aleksi Paaso M.A. Nayeem Maigha Maigha Daniel Kushner 《The Electricity Journal》2019,32(4):45-49
This paper presents part of the work ComEd and Quanta Technology have performed to quantify the locational and temporal value of DER to avoid distribution grid upgrade investments. It focuses on the formulation of a robust and efficient algorithm for DER optimal dispatch on a distribution feeder to mitigate the violation of current and voltage limits using the allocated cost of capacity and locational marginal value of real and reactive DER injection/withdrawal. 相似文献
68.
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
69.
《Planning》2019,(1)
伴随着医疗体系的改革,放射科医生的工作模式正在发生变化,由既往仅书写大量的放射影像报告转变为多学科诊疗团队的核心成员,在患者安全和医疗质量、教育、科普宣传、临床科学研究及卫生经济学等层面均发挥着重要作用。多学科诊疗模式为放射科医生提供了向临床各科室、患者、医疗机构和社会展现自我价值的重要机会。 相似文献
70.
BackgroundAvocado (Persea americana Mill.) is a tropical and subtropical fruit that is native to Mexico and Central America; avocado is gaining increasing worldwide acceptance and has received extensive marketing and a wide distribution due to its relevant nutritional benefits for human health. Mexico harvests more than 30% of avocados worldwide, representing the main producer and exporter of avocado, which has become a crop of high interest and has great economic impact on Mexico.Scope and approachIn this paper, we describe relevant information on the production, composition and application of avocado, with an emphasis on its by-products, focusing on the proper use of waste and the possibility of monetizing waste for nutritional and environmental purposes. The entire avocado is rich in biocompounds (pulp, seed and peel) and has many health benefits, such as antimicrobial, antioxidant and anticancer activities, as well as dermatological uses and others. In this paper, we demonstrate the current panorama of production, exportation and uses of avocado in Mexico.Key findings and conclusionsSeveral food grade ingredients can be obtained from avocado wastes, particularly premium-grade fats or extracts with a high functional power. Studies should continue to identify the profiles and phytochemicals available to the business sector, which can also be implemented to valorize the nutritional and functional potential of avocado seeds and peels. 相似文献