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1.
The performance of slag and fly ash in hydrated cementitious materials depends on the degree of reaction developed at the evaluated age. Several methods for the determination of the reaction degree of supplementary cementitious materials are available, among which the selective dissolution method is one of methods developed the earliest. This is a direct method that aims to quantify the amount of unreacted slag or fly ash in the sample by applying a selective acid attack. The degree of reaction is obtained from the comparison between the remaining unreacted SCM, which should not dissolve, and the total amount initially included in the mix. This recommendation indicates suitable procedures for computing the degree of reaction by selective dissolution of cement pastes containing slag and fly ash. Specific considerations are indicated for necessary corrections due to the imperfect selective dissolution when the procedure is applied to hydrated cement paste.  相似文献   
2.
Corals, like many other coelenterates, contain fluorescent pigments that show considerable homology with the well known green fluorescent protein of the jellyfish Aequoria. In corals, unlike jellyfish, multiple proteins are present and the range of excitations and emissions suggest the possibility of energy transfer. The occurrence of F?rster resonant energy transfer (FRET) between fluorescent proteins in corals has already been reported and time-resolved spectra have shown the effect on fluorescent lifetime, but without any spatial resolution. Lifetime confocal microscopy offers lower time resolution but excellent spatial resolution. Lifetimes of the isolated A. millepora pigments amilFP490, amilFP504, and amilFP593 (names indicate emission peaks) were 2.8, 2.9, and 2.9 ns, respectively. In the coral sample, imaging the entire emission spectrum from 420 nm, the mean lifetime was reduced to 1.5 ns, implying that FRET was occurring. Looking just at the fluorescence from FRET donors the lifetime was even shorter, at 1.3 ns, supporting this interpretation. In contrast, no reduction in lifetime is seen in the coral Euphyllia ancora, where the pigment distribution also suggests that the pigments are unlikely to be involved in photoprotection. This study set out to determine the extent of FRET between pigments in two corals, Acropora millepora and Euphyllia, ancora which differ in the arrangement of their pigments and hence possibly in pigment function.  相似文献   
3.
对时间序列随机性与神经网络预测精度的关系进行了研究.并将序列模糊滑动平均法用于神经网络预测中的训练样本预处理.以减小序列随机性成分。实例结果表明时间序列经模糊滑动平均处理后,随机波动对神经网络预测精度的影响可大大减小。  相似文献   
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While peak shaving is commonly used to reduce power costs, chemical process facilities that can reduce power consumption on demand during emergencies (e.g., extreme weather events) bring additional value through improved resilience. For process facilities to effectively negotiate demand response (DR) contracts and make investment decisions regarding flexibility, they need to quantify their additional value to the grid. We present a grid-centric mixed-integer stochastic programming framework to determine the value of DR for improving grid resilience in place of capital investments that can be cost prohibitive for system operators. We formulate problems using both a linear approximation and a nonlinear alternating current power flow model. Our numerical results with both models demonstrate that DR can be used to reduce the capital investment necessary for resilience, increasing the value that chemical process facilities bring through DR. However, the linearized model often underestimates the amount of DR needed in our case studies. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. AIChE J, 65: e16508, 2019  相似文献   
6.
基于神经网络和D—S证据理论的综合诊断模型   总被引:5,自引:0,他引:5  
故障诊断时,在考虑经济效益的基础上应尽可能地融合多种传感器信息进行综合诊断,以求得最佳诊断结果。本文提出了神经网络和D-S证据理论相结合的综合诊断模型,实例证明该模型具有良好的适应性并能得到准确性较高的诊断结果。  相似文献   
7.
One of the major concerns of research in integrated healthcare information systems is to enable decision support among clinicians across boundaries of organizations and regional workgroups. A necessary precursor, however, is to facilitate the construction of appropriate awareness of local clinical practices, including a clinician's actual cognitive capabilities, peculiar workplace circumstances, and specific patient-centered needs based on real-world clinical contexts across work settings. In this paper, a user-centered study aimed to investigate clinical practices across three different geographical areas-the U.K., the UAE and Nigeria-is presented. The findings indicate that differences in clinical practices among clinicians are associated with differences in local work contexts across work settings, but are moderated by adherence to best practice guidelines and the need for patient-centered care. The study further reveals that an awareness especially of the ontological, stereotypical, and situated practices plays a crucial role in adapting knowledge for cross-boundary decision support. The paper then outlines a set of design guidelines for the development of enterprise information systems for e-health. Based on the guidelines, the paper proposes the conceptual design of CaDHealth, a practice-centered framework for making sense of clinical practices across work settings for effective cross-boundary e-health decision support.  相似文献   
8.
Influence of fresh concrete and cement injections on the groundwater quality. This contribution presents the state‐of‐the‐art concerning the leaching behaviour of fresh concrete. The used test setups are shown and the measured release is specified for different applications. At the end two simulation examples for the transport of pollutants in the groundwater are shown.  相似文献   
9.
The emerging field of circular RNAs (circRNAs) has identified their novel roles in the development and function of many cancers and inspired the interest of many researchers. circRNAs are also found throughout the healthy body, as well as in other pathological states, but while research into the function and abundance of circRNAs has progressed, our overall understanding of these molecules remains primitive. Importantly, recent studies are elucidating new roles for circRNAs in pregnancy, particularly in the placenta. Given that many of the genes responsible for circRNA production in cancer are also highly expressed in the placenta, it is likely that the same genes act in the production of circRNAs in the placenta. Furthermore, placental development can be referred to as ‘controlled cancer’, as it shares many key signalling pathways and hallmarks with tumour growth and metastasis. Hence, the roles of circRNAs in this field are important to study with respect to pregnancy success but also may provide novel insights for cancer progression. This review illuminates the known roles of circRNAs in pregnancy and the placenta, as well as demonstrating differential placental expressions of circRNAs between complicated and uncomplicated pregnancies.  相似文献   
10.
Wireless Personal Communications - Fountain codes are rateless erasure codes that have initially been designed for multicast and streaming applications. They provide dynamic code rates which are...  相似文献   
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