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1.
利用"智慧芽"数据库对我国1997-2018年间的转基因小麦专利文件进行统计分析,从申请趋势、IPC分类、核心专利分析等层面得出转基因小麦技术发展趋势,从专利角度分析目前我国研究机构所面临的问题并提出专利布局的思路。  相似文献   
2.
Using a rolling cross-sectional sample of over 40,000 U.S. snack food consumers during 2004–2010, we build a three-dimensional model to study how portion sizes, consumption context, and package characteristics jointly affect the amount of food consumed. As with prior research, we find that consumption does increase with larger portions. However, this effect diminishes significantly when accounting for the consumption context and packaging characteristics as consumption drivers. Most important is how the snack is presented to consumers at the point of consumption (type, size, and quantity of packages). We also find that snacking on impulse, alone, with a beverage, or while watching television increases the amount consumed, whereas socializing or snacking at home decrease consumption. We test our model over seven snack types (potato chips, crackers, cheese puffs, nuts and seeds, tortilla chips, pretzels, popcorn), and find that our results hold even for products with different cross-category granularity, palatability, and satiety.  相似文献   
3.
李雨时 《价值工程》2021,40(2):126-128
目前在市政净水处理厂和企业生产用水处理厂由于斜板发生型变、位移、滋生藻类造成滑泥不顺畅甚至堵塞致使最后的水处理工艺出水水质达不到生产、生活要求的现象较多。其原因在于混凝-沉淀的一般性斜板在使用过程中存在两个问题,一是热熔焊接的斜板,焊点凹凸不平,容易积泥、滋生细菌和藻类影响斜板的水力条件,再有问题是塑料斜板在紫外照射的时候存在老化发生型变、型变过程伴随着斜板的位移从而很大程度影响斜板的水利条件和使用寿命。本文采用改性PET斜板解决了上述问题,并应用到工程实际当中去,取得了预期的效果。改性无毒PET材质大幅提高了沉淀板的抗蠕变、耐疲劳、耐摩擦等机械性能,PET材料耐酸碱、抗日晒、防老化、耐高低温等优异的化学性能应用于工程水处理设备,带来的是水处理设备材料的革命。  相似文献   
4.
With the expansion of urbanization caused by the growth of population and industrial activities, the urban/city and suburban areas are facing a variety of environmental threats. Although more research and urban policy has advocated and practiced the development of green infrastructure (GI) to support urban sustainable environment, the evaluation framework for the development of GI for promoting environmental sustainability is still insufficient. Moreover, the Analytic Hierarchy Process (AHP) commonly applied in published literature, makes an unrealistic assumption of independent relationships among dimensions/criteria in decision making for satisfying the real-world problem. Therefore, the purpose of this study is to construct the evaluation framework, including four dimensions and related ten criteria, using a new hybrid-modified multiple attribute decision-making (MADM) model for developing and improving the GI for promoting environmental sustainability. This MADM model is combined with three different methodologies of MADM, including the Decision-Making Trial and Evaluation Laboratory (DEMATEL) for constructing the influential network relation map (INRM) to explore the complex influential inter-relationships and DEMATEL based on Analytic Network Process (DANP) for determining the influential weights with the VIse Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) for evaluating and presenting improvement strategies for six different GIs. The empirical study indicates that DEMATEL and DANP Results suggest that decision-makers should pay more attention to the improvement of Design (D4) and Materials (D2) in terms of dimensions when utilizing the GI to promote environmental sustainability. Because these dimensions are enhanced, Species (D1) and Energy (D3) will be improved in synchronization. From the perspective of criteria, five are key core criteria and need to be focused on first: increasing the green coverage rate (B9), utilizing sustainable materials (B4), using ecological engineering (B8), shaping species biodiversity (B1), and reducing energy consumption (B5). Modified VIKOR reveals that “grass swales” are a comparatively better choice among six GIs for promoting environmental sustainability toward achieving the aspiration level. Therefore, this MADM model is beneficial to provide a more convincing assessment framework and improvement strategies for the development of GI for promoting environmental sustainability. As a result, these modified MADM models can be shown more conveniently and reasonably than traditional methods such as traditional AHP or ANP method.  相似文献   
5.
In 2016, second-generation genetically modified (GM) potatoes were approved for production and sale in Canada. In this study, we analyze how consumer acceptance of GM potatoes may be affected by various factors, including the trait introduced (i.e., the product benefits), the type of breeding technology used, and the developer of the potato using any technology. We conduct an online survey and use a stated choice experiment to collect data on consumer acceptance of GM and other potatoes in Canada. Random utility models are used to analyze the economic value consumers place on the various attributes of the potatoes. Our results show that consumers are willing to pay more for a health attribute (reduced acrylamide produced when potatoes are fried) and an environmental attribute. Respondents in general need to face discounted prices to buy potatoes created by either gene editing or GM (either transgenic or cisgenic/intragenic) technologies. However, consumers are in general more accepting of the gene editing technology than the GM technologies. Our results also show that government is the most preferred developer of the potatoes, regardless of technology. Results from this study can help guide public and private management of the introduction of new foods when the products are developed with unpopular technologies.  相似文献   
6.
Abstract

The present study investigates how the most foundational factors to individual differences – personality traits and personal values – affect the perceived safety of genetic modification and their relative importance. Publicly available communication data from 522 Twitter accounts discussing genetically modified foods and their safety was processed in two steps. First, accounts were categorized by the researchers as viewing GM foods as either safe or not safe. Second, using the IBM Watson platform, the Twitter communication data were subjected to lexical analysis to assign scores according to the Five Factor Model for personality traits and Schwartz’s basic individual values to the individual accounts. Logistic regression analyses were performed to determine how perceived GM food safety is linked to personality traits and individual values. Although both traits and values significantly contribute to explaining GM attitudes, personality traits strongly moderate the effect of individual values on risk perception.  相似文献   
7.
Consumers have grown increasingly aware of the impact of packaging on the environment. Therefore, interest has grown in more environmentally friendly packaging, but we wondered how consumers recognize ‘green’ as distinct from ‘grey’ when evaluating packaging. We asked over 3,000 respondents from Germany, France and the United States how they recognize environmentally friendly packaging. To solicit responses that we may not have anticipated, we used an open‐ended format, which we then followed with a closed‐ended format so that we could compare the two sets of responses. Not surprisingly, in both sets of responses, we found labelling to be the attribute consumers rely upon most, as well as evidence of misleading labels. We also found consumers in Germany and the United States relied on information on the packaging and named searching for information as one of their preferred ways to decide whether packaging is environmentally friendly. French consumers seemed less trusting of published information and more trusting of the look and feel, especially the material, of the package. Our results point to the importance of cultural influences in the acquisition of perceptual cues by the consumer.  相似文献   
8.
9.
为了解决运用传统的专利文本分析方法中出现的分类粗糙、科学性不强等问题,提出使用基于Latent Dirichlet Allocation(LDA)主题模型的专利文本分析方法。以我国转基因玉米育种领域专利文本为研究对象,对专利文本主题进行划分。通过实验表明LDA主题模型对专利文本的划分和热门领域的分类准确、有效。并得出结论:对专利文本使用LDA主题模型建模可以实现对专利文本的分类,可以实现对热门领域主题分类、子领域细分,并对未来发展态势给出意见。  相似文献   
10.
为解决证据融合时证据间冲突衡量不准确问题,提出了一种新的证据冲突衡量方法。对当前冲突衡量方法国内外研究现状进行总结,结合典型算例分析,指出了当前方法存在的主要问题。基于前人研究成果,提出了一种改进冲突因子用于衡量证据间冲突,主要基于修正证据距离与合取冲突,对两者采用加性组合。通过一般类型算例与特殊类型算例对所提方法进行验证,结果表明改进的冲突衡量因子能够准确衡量证据间冲突,并具有普适性。  相似文献   
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