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951.
为实现回声测深仪主机精确计量检定及远程在线计量检定问题,开发了一种回声测深远程校准系统。采用STM32单片机作为数据采集的核心元件,包括电源供电模块、信号处理接收模块、信号发生输出模块、显示延时控制模块、信号通信交互模块;通信模块通过USB串口、RS485及无线WIFI网络系统,实现回声测深仪主机的远程在线校准和远程交互。试验结果表明:该回声测深远程校准系统检定精度符合国家计量检定标准(最大允许误差为±1%d,其中d为实测水深值),且远程校准测试和现场校准测试误差率在2%以内。该回声测深远程校准仪系统为进一步推广远程在线计量研究打下了坚实基础。 相似文献
952.
静压管桩在实际工程中有着广泛应用,桩-土界面超孔隙水压力对静压桩的工作性能有着巨大影响。目前的研究多集中于桩周土中超孔隙水压力的分布,缺少对桩-土界面处应力的真实情况的研究。通过在桩身开孔、嵌入硅压阻式孔隙水压力传感器的方法,在黏性土体中开展了2组模型桩的室内静力压桩试验,对桩-土界面的孔隙水压力、超孔隙水压力的变化规律进行了研究。试验结果表明:利用硅压阻式传感器首次成功监测了沉桩过程中桩-土界面产生的孔隙水压力;2根试桩在沉桩过程中产生的桩-土界面孔隙水压力、超孔隙水压力均随着沉桩深度的增加而增大;同时2根试桩沉桩过程中产生的超孔隙水压力均较大,最大可达4.21 kPa,约为上覆有效土重的75%,在实际工程中需对沉桩过程中产生的较大超孔隙水压力加以重视;同一深度处的超孔隙水压力存在消散现象,随着深度的增加,消散程度逐渐减小;在实际工程中,需采取有效措施,防止超孔隙水压力过大。试验结果可为静压桩施工和桩-土界面理论研究提供参考。 相似文献
953.
We describe the modular architecture of a generic dialogue system that assists a user/operator in performing a task with a tool. This coaching system is named CALLIOPE after the Greek goddess of eloquence. It aims at being an active partner in an intelligent man-machine dialogue. The intelligent dimension of the coaching system is reflected by its ability to adapt to the user and the situation at hand. The CALLIOPE system contains an explicit user model and world model to situate its dialogue actions. A plan library allows it to follow loosely predetermined dialogue scenarios.The heart of the coaching system is an AI planning module, which plans a series of dialogue actions. We present a coherent set of three dialogue or speech actions that will make up the physical form of the man-machine communication.The use of the AI planning paradigm as a basis for man-machine interaction is motivated by research in various disciplines, as e.g., AI, Cognitive Science and Social Sciences. Starting from the man-man communication metaphor, we can view the thinking before speaking of a human communication partner as constructing an underlying plan which is responsible for the purposiveness, the organisation and the relevance of the communication.CALLIOPE has been fully implemented and tested on theoretical examples. At present, also three tailored versions of CALLIOPE are in operational use in different industrial application domains: operator support for remedying tasks in chemical process industry, operator support for a combined task of planning, plan execution and process control in the area of chemical process development, and thirdly decision support in production scheduling. 相似文献
954.
Based onin-situ Mössbauer and X-ray diffraction studies, it is shown that in the Fe/TiO2 catalyst, the anatase-rutile transformation of the TiO2 support is facilitated by the Fe2+ ions formed during the reduction. The transformation occurs at lower temperatures in Th/TiO2 and Cu/TiO2 compared to pure TiO2. In general, the transformation of anatase to rutile seems to occur at or below the temperature (770 K) at which strong-metal-support-interaction manifests itself.Contribution No. 718 from the Solid State and Structural Chemistry Unit. 相似文献
955.
956.
Conservation of historical buildings is an important issue. The environmental conditions seriously affect the monumental stones. Although different coating materials were tested, the polymeric materials have been showing the most promising results for protection of archeological stones. Therefore, in the current study, the acrylic polymer was used for conservation of monuments made of sandstone and limestone. The adsorption of the acrylic polymer onto both stones was analyzed and the durability of the coatings under different environmental conditions was tested and simulated by artificial aging. Moreover, the mechanism of polymer-stone interactions was elucidated by interfacial characterization techniques.The results showed that the adsorption of polymer onto either stones is physical as shown by Fourier transform infra-red (FTIR) and electrokinetic measurements. In addition, the presence of polymer coating shows a significant improvement in physical and mechanical properties of the treated stones, e.g., increase in bulk density from 1.9 to 2.3 g/cm3 and decrease in porosity from 15.8% to 2.7% as well as the noticeable increase in compressive strength. All these measures indicated the suitability of acrylic polymer for conservation of either stones. 相似文献
957.
Collaboration with artificial intelligence (AI) is a growing trend even in the field of creativity. This paper examines which quantitative metrics can be used to comparatively analyse human-computer co-creativity with children. To study this question, 24 schoolchildren of age 10–11 wrote a poem with three co-creative poetry writing processes: a human-computer, a human-human, and a human-human-computer process. The computational participant in the processes was an AI-based application called the Poetry Machine. The children were asked to evaluate their user experience with a 5-point Likert-type questionnaire after each writing process and a comparative questionnaire after finishing all processes. The metrics used in the evaluation were immediate fun, long-term enjoyment, creativity, self-expression, outcome satisfaction, ease of starting and finishing writing, quality of ideas and support from others, and ownership.
Significant differences were found in fun, long-term enjoyment, quality of ideas, support, and ownership. The high number of statistically relevant results was enabled by exposing all participants to all writing processes, and the comparative questionnaire. The human-human-computer process was evaluated the best in long-term enjoyment and the human-computer process the weakest in support and idea quality. Creativity and ease of finishing writing turned out to be outlining metrics for the co-creative processes. 相似文献
958.
Cui Hu Zhan Wu Hao Tang Li-Juan Tang Ru-Qin Yu Jian-Hui Jiang 《International journal of molecular sciences》2014,15(4):5221-5232
Methods for the detection of specific interactions between diverse proteins and various small-molecule ligands are of significant importance in understanding the mechanisms of many critical physiological processes of organisms. The techniques also represent a major avenue to drug screening, molecular diagnostics, and public safety monitoring. Terminal protection assay of small molecule-linked DNA is a demonstrated novel methodology which has exhibited great potential for the development of simple, sensitive, specific and high-throughput methods for the detection of small molecule–protein interactions. Herein, we review the basic principle of terminal protection assay, the development of associated methods, and the signal amplification strategies adopted for performance improving in small molecule–protein interaction assay. 相似文献
959.
传统基于WIMP界面范式的表格设计,无法满足用户与界面自然、高效、连续性交互的需求,尤其是用户无法根据设计意图自由勾画任意通用的表格,也无法自动标识表格界面逻辑.提出一个基于笔交互的表格组件的设计方法.该方法以数字笔代替鼠标键盘,能够连续输入笔迹并识别为文字、勾画草图并识别为正式表格或框线、使用笔手势操纵界面对象,并能自动识别表格的逻辑结构.本文讨论了该笔式表格组件的开发框架及关键技术,以及表格组件架构,并给出了应用实例及性能评估,实验结果表明,用户使用该方法设计表格具有较高的效率与用户满意度. 相似文献
960.
随着法律文书数据越来越多,信息过载问题日益严重,快速且准确地在海量法律文书中进行检索显得非常必要。法律文本作为一种特殊的文本形式,具有篇幅较长、结构复杂、专业性强等特点,传统基于关键字的文本检索方法不能满足用户查询法律信息的需求,容易出现答非所问、检索不全等问题。此外,基于语义的文本检索方法,大多依赖于对含有大量标注数据的法律文本进行有监督学习,而法律文本数据的人工标注则严重依赖专家知识,导致其需要高昂的人力成本。该文提出一种基于无监督学习的法律文书检索模型,分别从法律概念、词语和词组3个方面进行多粒度无监督文本匹配,避免了没有训练数据导致的冷启动问题。在法律裁判文书数据集上进行检索实验的结果表明,与基准模型相比,该模型在MAP、MRR和NDCG@10指标上均有显著提升,取得了优秀的检索效果,具有有效性和先进性。 相似文献