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141.
碳标签可以标识产品生命周期所产生的碳排放量,具有更低碳排放量的产品可增加消费者的支付意愿,从而促使供应链上下游企业产生减排意愿。基于供应链视角,采用博弈论方法对供应链的减排行为进行研究,结果表明上下游企业的减排贡献与技术减排能力成正比,即在碳排放标签政策的市场调节下,减排资源将向减排能力强的企业转移。同时,领导者企业将支持而跟随者企业可能抵制碳标签政策的实施,政府在碳排放政策制定中应对跟随者企业给予适当的倾斜。 相似文献
142.
认知无线电是一种可用于有效缓解当前频谱资源紧张的技术,而频谱感知是认知无线电的前提。针对低信噪比情况下频谱感知性能差的问题,提出一种将信号高阶统计量、协方差矩阵特征值与神经网络相结合的合作频谱感知算法。该算法考虑到认知用户与授权用户的信道衰落情况,利用神经网络较强的多分类能力,将最大-最小特征值之比、平均-最小特征值之比以及高阶统计量作为特征参数,通过神经网络实现合作频谱感知。仿真结果表明,该算法不仅在低信噪比情况下较其他算法具有更高的频谱检测率,而且对频谱中信号的调制类型也有较高的识别率。 相似文献
143.
For many young people in England, the move into continuing education involves a transfer from the school where they were educated to a further education college. For those with high‐functioning autism or Asperger's syndrome, this can be a challenging process. Past research has demonstrated some of the problems that these young people can encounter. This article by Wendy Mitchell and Bryony Beresford, both based in the Social Policy Research Unit at the University of York, adds to the evidence base by describing how best to support these young people, focusing specifically on ‘young person endorsed’ practice. Data are gleaned from qualitative interviews with 18 young people with high‐functioning autism/Asperger's syndrome. Findings reveal that young people welcomed the involvement of practitioners; however, specific forms of help and knowledge were particularly valued. In addition, it was parents, as opposed to professionals, who typically emerged as the most significant and valued source of support. Implications for practice are discussed, including the support needs of parents. 相似文献
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本文阐述扩频通信的工作原理及目前无线局域网的特点和主要传输方式,并就扩频通信的四种工作方式、扩频技术的特点和扩频技术在无线局域网中的应用前景等作了介绍 相似文献
146.
熊缨 《深圳信息职业技术学院学报》2008,6(4):81-84
约占室内装饰材料70%的人造板和木材复合材料是室内甲醛的主要来源。我国使用的板材以中密度纤维板为主。影响中密度纤维板甲醛释放的原因较多。主要创新及意义:本文选用模拟气候箱法对不同厚度及经过不同饰面处理的中密度纤维板进行试验,得出其甲醛释放的规律。 相似文献
147.
Traci-Ann Garrad Christopher Rayner Scott Pedersen Monica Cuskelly 《Journal of Research in Special Educational Needs》2021,21(4):381-391
Many teachers are sporadic in using evidence-based practice (EBP) concerning students with autism spectrum disorder (ASD). Numerous reasons have been posited for this. However, no single study has worked to understand the relative importance of identified criteria in the EBP decision-making processes of teachers. Through the development of a new survey tool, the Evidence-Based Practice Innovation Survey (EBPIAS), an exploration of the decision-making process of Australian teachers in their adoption and cessation of EBP was undertaken. Teachers rated the perception that an EBP would meet the needs of their students as the most important criteria in determining their use of EBP. Conversely, the judgement that an EBP did not meet the needs of their student was the most important criteria in their decision to cease use. In comparing the relevant importance of identified criteria, teachers rated the perception of training as the second-lowest consideration in their decision to adopt and cease using EBP. Consequently, there may need to be greater promotion of, or information concerning, the training required by teachers for effective implementation supporting a more balanced and holistic approach in assessing criteria impacting the adoption of EBP by teachers in the first instance, potentially lowering cessation rates. 相似文献
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149.
红外光谱技术是一种高效、快速的现代分析技术,而Microsoft Excel是一个功能强大的数据处理软件,两者均在很多领域得到了广泛应用。该文利用苯甲酸红外光谱实验数据为操作对象,介绍了用Mi-crosoft Excel软件处理该类型实验数据的详细步骤,包括数据引用方法、图表绘制及其修饰等相关技术。 相似文献
150.