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41.
通过对干喷、湿喷、并列法喷护的剖析,针对其利弊开发出另一种介于干喷和半湿喷护方法,并对半湿喷护法的优缺点加以分析,探讨了半湿喷护法的工艺流程、喷嘴结构形式、水环结构及其效应。初步试验成果表明,半湿喷护法在技术上是可行的,经济效益也显著,可在逐步研究完善后推广应用。 相似文献
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To examine whether long reviews are uniformly more useful to readers, this study utilizes the experimental design approach to investigate the interplay of review depth, review breadth, and review language style on readers’ perceived usefulness and adoption intention of online hotel reviews. Drawing on the results from two experiments, review depth is proven to exert a positive impact on readers’ review usefulness and adoption intention. The moderating role of review breadth is verified, and the positive effect of review depth on review usefulness is attenuated (accentuated) when review breadth is high (low). The moderating role of review language style is also confirmed, and the result shows longer reviews written in literal language are considered more useful to readers than those written in figurative language. Being one of the first studies examining the interplay of review content and review style on review usefulness, this study provides important theoretical and practical contributions. 相似文献
44.
小底坡梯形明渠临界水深求法探讨 总被引:2,自引:0,他引:2
本文提出了一条求解小底坡梯形明渠临界水深的新途径——预估修正法。方法以简单的数值逼近原理为基础,没有繁复的数学推导,也不需要物理假设,所以使用时不必依赖图表。数值实践证明:该方法简单易行,且仍能保证较高的精度,可供工程实际推广应用。 相似文献
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Julia E. Carins Sharyn R. Rundle-Thiele Justin J. T. Fidock 《Journal of Marketing Management》2016,32(11-12):1083-1102
ABSTRACTThe purpose of formative research in social marketing is to understand the target audience to generate consumer insight, which informs the planning, development and initial implementation of social marketing programmes. Focus groups, interviews or surveys, all of which are self-report methods, are the most commonly reported methods employed in formative research. Reliance on a relatively narrow range of methods may constrain understanding and insight gained during formative research. This paper challenges social marketers to mix methods or use multiple methods and research perspectives to generate a broader understanding of the consumer and the context in which they behave. A case study is used to demonstrate how mixed methods were used in a formative research study to inform the development of a social marketing programme designed to change eating behaviour. Challenges of mixed methods are detailed along with recommendations for future research. 相似文献
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Perceptions of older consumers regarding food packaging as a prerequisite for its improvement: A case study of Polish market 下载免费PDF全文
Jarosław Świda Michał Halagarda Stanisław Popek 《International Journal of Consumer Studies》2018,42(3):358-366
In many societies, the scale of demographic change associated with increased longevity has the potential to influence the market for consumer goods. As a result, continuous improvement in packaging design that takes into account the needs of older people should become an important challenge for both packaging producers and product manufacturers. Due to the fact that there is limited research concerning the design of food packaging for older people, the aim of the study was to identify the expectations of this group of consumers in this respect. Milk packaging was selected as a model subject of study. Factors influencing older consumers and their buying patterns when purchasing milk have been thoroughly examined. The research was conducted among people over the age of 60 with the use of three methods: a questionnaire (600 subjects), an in‐depth interview (60 subjects) and eye tracking (30 subjects). The results of the study show that older consumers have specific preferences regarding packaging type and design. When considering milk packaging, for example, they prefer glass bottles, simple graphics and font and subdued colours. They most frequently look for information concerning the product's expiration date, its producer's name and its composition. Eye tracking revealed that the older the consumers are, the more problems with finding expiration date they have. The time required to find such information, however, strongly depends on where exactly the expiration date is printed on the packaging. The preferred place in this case is the top of the bottle. Older consumers identify product's brand with the name of the producer. Moreover, the absence of the term ‘ingredients’: on the milk packaging oftentimes causes confusion among older people, who are concerned about potential food additive content. 相似文献
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为提高玄武岩残积土的抗崩解性及其边坡水稳性,利用生物聚合物瓜尔胶改良玄武岩残积土。在干湿循环条件下开展不同掺量瓜尔胶改良玄武岩残积土的崩解试验,观察残积土崩解过程,并对残积土改良土崩解系数和平均崩解速率进行测定,分析瓜尔胶掺量及干湿循环次数对玄武岩残积土水稳性的影响。研究结果表明:瓜尔胶可有效增强玄武岩残积土的抗崩解性能,随着瓜尔胶掺量的增加,改良玄武岩残积土的崩解系数和平均崩解速率呈现先减小后增加的特点,在瓜尔胶掺量为1.0%时抗崩解性能最佳;瓜尔胶掺量一定时,改良玄武岩残积土的崩解系数和平均崩解速率随着干湿循环次数的增加呈现增长趋势,当干湿循环次数N=4时,土体崩解率为N=1时的8倍。由此可见,瓜尔胶作为一种新型、环保的残积土边坡防护材料,可有效提升玄武岩残积土的抗崩解性能。研究结果为生态环保处置玄武岩残积土提供了新的思路,可为玄武岩残积土地区边坡工程的绿色发展提供参考。 相似文献
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This study examines why most derivatives markets that settle on the day following expiration choose the opening rather than the closing price as the final settlement price (FSP), whereas most markets that settle on the expiration day select an average rather than a single price as the FSP. Four exogenous changes in the Taiwan Futures Exchange settlement procedures provide an experimental basis for studying the settlement procedures’ impact on underlying assets. Greatest market efficiency is observed when the FSP is determined by a single rather than an average price and hypothesize that manipulation is prevented at the expense of market quality. 相似文献
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小湾拱坝湿筛混凝土动态弯拉力学特性试验研究 总被引:2,自引:0,他引:2
结合小湾拱坝,试验研究了湿筛混凝土动态弯拉力学特性。试验采用MTS322动静万能试验机和简支梁三分点加荷法。静载试验加载速率为250N/s。动载试验考虑了不同初始静载(0%、40%、80%、90%)和不同动态加载方式(冲击和变幅三角波)。40%、80%和90%初始静载分别取18.6kN、37.2kN和41.8kN,以静载速率加载至初始静载值,再施加动态荷载。冲击波形加载速率是250kN/s。变幅三角波形加载频率是1Hz,每个加载台阶含三个周期,相邻加载台阶差值是20kN。湿筛混凝土试验结果表明:(1)初始静载对混凝土动态极限弯拉强度影响很大;(2)合适比例的初始静载对混凝土动态极限弯拉强度有利,本文试验发现80%初始静载时动态弯拉强度提高最大,冲击试验DIF高达1.49;(3)同静载相比,冲击加载时混凝土动态极限弯拉强度提高,弯拉极限拉伸值略小,弹性模量提高不多,纯弯区正截面中和轴位置没有变化;(4)往复加载对混凝土存在低周疲劳的不利影响。对比分析表明,三级配混凝土与其湿筛混凝土动态弯拉力学特性,定性规律相似,但定量结果尚得不出来,进行高拱坝抗震设计时,应采用全级配混凝土动态试验结果。 相似文献