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11.
DAVID G ELMS 《Civil Engineering and Environmental Systems》2013,30(3):265-272
Learning about complex systems is a fundamental engineering skill; it is often the first task of an engineer when faced with a complex problem in an unfamiliar context. The nature of learning is discussed. Contributions from cognitive psychology, artificial intelligence, management and sociology are drawn together to show that fundamentally, system learning is a matter of forming well-constructed system or conceptual models. The skills needed for this are discussed. 相似文献
12.
This paper investigates project changes and their relationships with stage iteration and multi-functional interaction. Changes often occur in a complex solution-based project, which makes the linear management model limited in its application. Complex project planning is based on assumptions about future events. Assumptions often fail and as a result the plans contain activities that are impossible or unnecessary to execute. The consistency of project planning needs to be restored and maintained by revising or redefining project activities. 相似文献
13.
研究结合大城市周边重点镇的特征,基于城镇空间的双重属性—中心城的辐射影响地区及局部区域的发展中心,提出"区域联动、地方联合"的规划策略,并结合南宁市金陵镇的规划实践案例探讨策略的合理性及适用性,以期为其他大城市周边重点镇的规划建设提供参考。 相似文献
14.
15.
《Soils and Foundations》2019,59(4):828-839
The response of a jointed pipeline to tunnelling-induced ground settlement relies largely on the soil-pipe interaction. An analytical solution incorporating the Pasternak model is formulated here to estimate a jointed pipeline's deflection and bending moment. Subsequently, a procedure is proposed to transform the jointed pipeline to an equivalent continuous structure for a deflection evaluation. Case studies are conducted to verify the analytical solution, followed by parametric studies to assess the effects of the Pasternak model's parameters and the pipe joints. The analytical solution is validated by the experimental results in the literature. The parametric studies show that the number and distribution of the joints have a mild effect on the pipe deflection, whereas their influence on the pipe bending moment is significant. Similarly, the pipe bending moment is more sensitive than the pipe deflection to subgrade shear stiffness. 相似文献
16.
iopeNet系统产品分为建筑内部和子系统连接的核心模块、可自由定制的iopeNet人机交互接口以及通过互联网连接到云端的iopeNet云服务等几部分。本文主要介绍iopeNet智能建筑管理系统中的人机交互接口部分,包括iopeNet系统操作界面、iopeNet系统操作台以及itpeNet标准配电箱内板。在系统安装使用过程中提供便捷的设备安装和友好的人机交互界面。 相似文献
17.
赵建华 《西华大学学报(自然科学版)》2015,39(1):36-40, 51
为提高半监督分类的性能,提出一种基于SOM神经网络的半监督分类算法SSC-SOM。结合SOM的聚类特性,基于先聚类后标记的思想,充分利用有标记样本和未标记样本训练SOM分类器;将聚类的形成和有标记样本分配到各个聚类中同时进行,并根据有标记样本计算各个聚类的聚类中心;在整个未标记样本的范围内,根据聚类中心,使用K近邻算法对未标记样本进行标记,挖掘未标记样本的隐含信息。在UCI数据集中进行分类实验,其结果表明,SSC-SOM的分类率比SSOM提高2.22%,且收敛性较好。 相似文献
18.
探讨槲皮素对高脂日粮小鼠学习记忆的影响及可能机制。4周龄C57B/L雌性小鼠45只,随机分为三组:对照组(基础日粮),高脂组(约20%脂肪),槲皮素组(高脂日粮+0.01%槲皮素)。第26周进行Morris水迷宫实验,实验结束后取小鼠大脑皮层和海马组织测定氧化应激指标,荧光定量PCR检测海马组织中脑源性神经营养因子(BDNF)、核转录因子Nrf2及血红素单加氧酶(HO-1)的基因表达。结果显示,高脂组小鼠学习记忆能力显著下降,脑组织出现明显的氧化应激,Nrf2、HO-1和BDNF基因表达显著下调;槲皮素干预后,大脑氧化应激程度减轻,Nrf2、HO-1和BDNF基因表达上调,学习记忆能力得到显著改善。槲皮素改善高脂日粮小鼠学习记忆,可能与上调Nrf2/HO-1通路及BDNF的基因表达有关。 相似文献
19.
Timofey V. Ivanisenko Pavel S. Demenkov Nikolay A. Kolchanov Vladimir A. Ivanisenko 《International journal of molecular sciences》2022,23(23)
The body of scientific literature continues to grow annually. Over 1.5 million abstracts of biomedical publications were added to the PubMed database in 2021. Therefore, developing cognitive systems that provide a specialized search for information in scientific publications based on subject area ontology and modern artificial intelligence methods is urgently needed. We previously developed a web-based information retrieval system, ANDDigest, designed to search and analyze information in the PubMed database using a customized domain ontology. This paper presents an improved ANDDigest version that uses fine-tuned PubMedBERT classifiers to enhance the quality of short name recognition for molecular-genetics entities in PubMed abstracts on eight biological object types: cell components, diseases, side effects, genes, proteins, pathways, drugs, and metabolites. This approach increased average short name recognition accuracy by 13%. 相似文献
20.
7,7,8,8-Tetracyanoquinomethane (TCNQ) was added to polyvinylpyrrolidone (PVP)/CuO composites to modify and prevent agglomeration of the particles, and thus the CuO particles were well dispersed to a small size, thereby increasing CO2 solubility and separation performance. When the separation performance of the PVP/CuO/TCNQ composite membrane was measured for CO2/N2 gases, a CO2 separation of about 174 was measured. This improvement in performance was attributed to the fact that TCNQ was applied to PVP and CuO to prevent agglomeration between particles with surface modification. Due to TCNQ, CuO could be dispersed to a small size in PVP; the bonds between chains in PVP weakened; the interaction between molecules weakened; and the free volume increased, as confirmed by FT-IR, TGA, and UV–Vis spectroscopy. 相似文献