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21.
内偏心轴承是胶印机离合压机构中通过调节滚筒间的中心距以实现合压和离压两种工作状态要求的重要部件.根据胶印机离舍压机构中内偏心轴承参数设计的基本准则和顺序离合压工艺要求,采用vC++面向对象程序设计技术和MFC方便友好的对话框编程界面进行参数化设计.通过在可视化界面上输入离合压机构的基本参数,可以方便快捷得到内偏心轴承的安装位置和关键参数,极大地提高了设计人员的工作效率.设计方法可以应用到不同类型、规格的胶印机顺序离合压机构的设计中,可缩短设计周期,提高设计效率. 相似文献
22.
《Journal of Great Lakes research》2020,46(5):1331-1339
Constructed and restored wetlands can be effective sinks for particulate and dissolved phosphorus (P) if properly managed, but identifying suitable P retention wetland locations remains challenging. From a landscape perspective, Soil and Water Assessment Tool (SWAT) models identify locations within target watersheds with high nutrient loads that exhibit appropriate site characteristics and hydrodynamics. However, soil properties vary at the field scale, dictating the capacity of wetland systems to remove P and ultimately determining if a given wetland will operate as a sink or source of P over time. Land ownership and site access further complicate identification of P retention wetland locations. As a result, optimization and identification of P retention wetland locations requires analysis at both 1) watershed and 2) field scales, and 3) public engagement. In response, a survey effort linked SWAT model results that identified locations with target watersheds with field soil P storage capacity data and interested landowners. Results suggest that several locations recommended for their high SWAT-predicted P loading and landowner interest were in fact not well suited for project implementation due to soil P saturation and legacy P constraints. These findings highlight the need to couple watershed models with field scale soils analysis to identify locations for P retention wetlands in order to avoid unintended P release. Additionally, increased collaboration with social scientists and others familiar with public engagement strategies is needed to improve outreach activities targeting regional water quality improvements. Practical applications for nutrient retention wetland site selection are also discussed. 相似文献
23.
扩大农村消费需求是推动经济增长的重要环节,但农民增收难度大、市场秩序和保障制度不健全、消费信贷约束等因素制约着我国农村消费需求发展。需要通过提高农村收入、加快基础设施建设、完善市场体系和保障制度、普及农村信贷等途径扩大我国农村消费需求,促进我国经济持续稳定发展。 相似文献
24.
张东伟 《郑州纺织工学院学报》2014,(3):75-78
以全美大学生学习性投入调查模型为工具,对河南省高校大学生学习性投入情况进行了问卷调查,通过与全国高校常模进行比较分析,找出河南省高校学生在学习性投入上存在的主要问题,以此为依据对高校教育教学提出改进性的意见和建议。 相似文献
25.
雷蒙德·卡佛是美国著名的小说家和诗人,其作品语言平铺直叙、精干冷硬。目前大多数研究都从其文本的"极简主义"特点出发,而鲜有研究从系统功能语法的评价理论角度入手。对小说中的评价性资源,如介入资源的自言、借言以及不同性质介入资源的使用和分布进行分析,对于探究其作品风格、语言特点等都有着重大的作用,同时,也为研究雷蒙德·卡佛的作品提供了新的视角和途径。 相似文献
26.
The decision regarding acceptance or rejection of a lot of products may be considered through variables acceptance sampling plans based on suitable quality characteristics. A variables sampling plan to determine the acceptability of a lot of products based on the lifetime of the products is called reliability acceptance sampling plan (RASP). This work considers the determination of optimum RASP under cost constraint in the framework of hybrid censoring. Weibull lifetime models are considered for illustrations; however, the proposed methodology can be easily extended to any location-scale family of distributions. The proposed method is based on asymptotic results of the estimators of parameters of lifetime distribution. Hence, a Monte Carlo simulation study is conducted in order to show that the sampling plans meet the specified risks for finite sample size. 相似文献
27.
Librarians can improve their online tutorials by borrowing usability testing techniques from the computer science field to improve the human-computer interface. This study involved a multimethod usability test of librarian-created tutorials to determine what students learned, how they felt on several affective questions, and what they suggested for improving the tutorials. Results of pre- and post-tests showed that student knowledge increased, and surveys and focus group findings lean to several suggestions for improving engagement and placing tutorials where they will be most effective. This case study demonstrates the value of user input to improve the effectiveness of online instruction for information literacy. 相似文献
28.
Evaluating the Wisdom of Strangers: The Perceived Credibility of Online Consumer Reviews on Yelp
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This study examined the effects of review valence, the reviewer profile, and the receiver's familiarity with the platform (user/nonuser) on the perceived credibility of a review on Yelp.com and on the receiver's attitude toward the reviewed object. The results demonstrated a difference in cue‐taking between users and nonusers. For users, there was an interaction effect of 2 profile cues (number of friends and number of reviews) on competence. Users interpreted the cues in combination, whereas non‐users were not influenced by them. The friends × reviews × platform familiarity interaction indirectly affected attitude through competence. Further, review valence was positively associated with perceived credibility and attitude. The findings support and extend the social information processing theory and cue combination literature. 相似文献
29.
Hannah Grainger Clemson 《Digital Creativity》2013,24(4):330-342
AbstractWith a growing number of embedded digital experiences in arts and heritage settings, creating a broad global field, this article focuses on the use of mobile phones in the engagement of humans with the cultural heritage of public spaces, specifically those that require a promenade from one outdoor space to another. This article discusses findings from a recent promenade initiative, commissioned for a UK arts festival, along with a review of literature, to critically engage with growing evidence of the diverse ways in which technology is integrated at direct user level. Concepts of ‘hybrid spaces’ and ‘user agency’ are discussed, along with the ‘performativity’ of spaces. Central to the discussion is the function of narrative in engaging the participant to construct new perspectives, which are facilitated by the mediating role of personal media devices between subject, narrative, space and community. 相似文献
30.
Wei Sha 《Electronic Markets》2009,19(1):43-54
This study examines the effects of different types of structural assurance mechanisms on trusting intention in business-to-consumer
electronic commerce. Inconsistent results from prior research on structural assurance motivated the current study to further
explore the nature of structural assurance. Based on the Institution-based Trust Theory, this paper proposes that different
types of structural assurance mechanisms, specifically: seals of approval, vendor-specific guarantees, protections from credit
card companies and transaction protections, may have their unique effects on trusting intentions. The results indicate that
customer perceptions about seals of approval and vendor-specific guarantees can significantly influence trusting intentions
while perceptions about protections from credit card companies, legal systems and technology infrastructures do not. 相似文献