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1.
自动化实体描述生成有助于进一步提升知识图谱的应用价值,而流畅度高是实体描述文本的重要质量指标之一。该文提出使用知识库上多跳的事实来进行实体描述生成,从而贴近人工编撰的实体描述的行文风格,提升实体描述的流畅度。该文使用编码器—解码器框架,提出了一个端到端的神经网络模型,可以编码多跳的事实,并在解码器中使用关注机制对多跳事实进行表示。该文的实验结果表明,与基线模型相比,引入多跳事实后模型的BLEU-2和ROUGE-L等自动化指标分别提升约8.9个百分点和7.3个百分点。  相似文献   
2.
Computer‐Interpretable Guidelines (CIGs) are the dominant medium for the delivery of clinical decision support, given the evidence‐based nature of their source material. Therefore, these machine‐readable versions have the ability to improve practitioner performance and conformance to standards, with availability at the point and time of care. The formalisation of Clinical Practice Guideline knowledge in a machine‐readable format is a crucial task to make it suitable for the integration in Clinical Decision Support Systems. However, the current tools for this purpose reveal shortcomings with respect to their ease of use and the support offered during CIG acquisition and editing. In this work, we characterise the current landscape of CIG acquisition tools based on the properties of guideline visualisation, organisation, simplicity, automation, manipulation of knowledge elements, and guideline storage and dissemination. Additionally, we describe the CompGuide Editor, a tool for the acquisition of CIGs in the CompGuide model for Clinical Practice Guidelines that also allows the editing of previously encoded guidelines. The Editor guides the users throughout the process of guideline encoding and does not require proficiency in any programming language. The features of the CIG encoding process are revealed through a comparison with already established tools for CIG acquisition.  相似文献   
3.
Numerical simulation techniques such as Finite Element Analyses are essential in today's engineering design practices. However, comprehensive knowledge is required for the setup of reliable simulations to verify strength and further product properties. Due to limited capacities, design-accompanying simulations are performed too rarely by experienced simulation engineers. Therefore, product models are not sufficiently verified or the simulations lead to wrong design decisions, if they are applied by less experienced users. This results in belated redesigns of already detailed product models and to highly cost- and time-intensive iterations in product development.Thus, in order to support less experienced simulation users in setting up reliable Finite Element Analyses, a novel ontology-based approach is presented. The knowledge management tools developed on the basis of this approach allow an automated acquisition and target-oriented provision of necessary simulation knowledge. This knowledge is acquired from existing simulation models and text-based documentations from previous product developments by Text and Data Mining. By offering support to less experienced simulation users, the presented approach may finally lead to a more efficient and extensive application of reliable FEA in product development.  相似文献   
4.
崔铁军    李莎莎 《智能系统学报》2020,15(5):998-1005
为将系统故障演化过程(system fault evolution process,SFEP)的文本描述转化为空间故障网络(space fault network,SFN)结构,用于故障分析,本文提出SFEP文本因果关系提取方法,及其与SFN基本结构的转化方法。首先给出SFEP中事件的几种典型因果关系。随后提出因果关系与SFN基本结构的转化流程。本文方法围绕着关键字和因果关系组模式展开,通过模型的不断学习补充和丰富关键字和组模式。最终使方法具备将SFEP文本转化为SFN结构的能力。以飞机起落架故障发生过程文本为例进行了应用,实验结果表明该方法可用于SFEP文本中的因果关系分析,并得到了理想的SFN。完善的关键字和组模式有利于使用计算机智能处理SFEP的SFN。  相似文献   
5.
Two-beam laser welding (TBLW) is an advanced process for precise, low distortion joining of cylindrical miniature parts. The process is composed of a laser source, optics and various actuators, which form a sophisticated system for control and maintenance in high volume manufacturing. A well-established method for identifying welding defects and ensuring welding quality is the monitoring of plasma light emission in TBLW. Although such monitoring systems can detect a change in process status, they are not able to diagnose the nature of the fault. The main challenge in this research was to extend the use of quality-based monitoring systems to measure additional deterioration-related parameters and to estimate system deterioration from them by using expert knowledge.This paper shows a novel condition-based maintenance (CBM) for the TBLW system, which performs condition identification using online monitoring of plasma light emission in combination with offline inspection of the seam macrographs. A combination of quality parameters derived from seam macrographs of defective parts is used to identify process deterioration, such as contamination of the optics, misalignment of the optomechanical system, or reduced laser power. The information obtained is used to make predefined process adjustments based on expert domain knowledge. The implementation of the developed CBM in high volume manufacturing of piezoelectric pressure sensors resulted in more predictable TBLW by reducing system failures as well as shorter diagnosis times.  相似文献   
6.
Tacit knowledge is an important factor for enterprises and institutions to enhance their knowledge innovation and value-added capabilities, and it is also a basic link to enhance organizational learning capabilities. With the development of technology, the dissemination of tacit knowledge has increasingly shown complex and dynamic trends. In order to make the tacit knowledge in the enterprise better circulate and generate greater economic value, therefore, this paper proposes a study on the diffusion map of tacit knowledge based on multivariate statistics and 3D visualization analysis. First of all, this paper analyzes the internal relationship between organizational learning and organizational tacit knowledge integration and organizational tacit knowledge innovation, and combines multiple statistical methods to propose an organizational tacit knowledge integration method based on tacit knowledge management. Secondly, we combine 3D visualization and generative confrontation network methods to analyze the data of tacit knowledge dissemination, and visualize the distribution of knowledge dissemination in three dimensions. In the simulation experiment test, this paper reveals that the spreading efficiency of tacit knowledge in the network is affected by related factors. Through this model, we hope to explore the behavioral laws of different types of nodes in the network and propose effective countermeasures to improve the efficiency of knowledge dissemination.  相似文献   
7.
田源 《计量学报》2019,40(4):583-588
为了提高图像去雾效果,提出混合远景和近景区域暗通道算法。首先建立远景和近景区域暗通道,为近景区域最小值通道和远景区域最小值通道之和,不同区域设置不同的调节系数;接着估计大气光值,通过混合暗通道远景区域的前50个像素点颜色值的平均值获得,增设校正系数;然后导向滤波,采用自适应滑动窗口优化透射率;最后给出了算法流程。实验仿真显示所提算法去雾图像视觉效果较好,定量分析指标对比度、可见边对比度值较优。  相似文献   
8.
苏里格气田是中国典型的致密砂岩气藏,构造简单、平缓,横向非均质性强,有效储层与围岩声学特征差别小,地震响应不明显,常规地震监测方法预测难度大,但气田含气砂岩泊松比低,是地震气藏检测的有效参数。利用弹性全波形反演精度高和能处理复杂非均质介质的优势,反演地层拉梅常数、剪切模量和密度,并计算泊松比,从而进行气藏预测。重点阐述了苏里格气田多分量数据全波形反演初始模型建模、先验模型建模和地震数据预处理3个关键问题的处理方法。二维三分量数据反演和"甜点"预测结果表明:①对于具有强非均质性的苏里格气田,利用全波形反演获得精度较高的地层弹性参数能显著提高气藏预测的准确度;②苏里格地区构造简单、平缓,利用常规叠加速度并结合构造解释可以建立比较好的初始模型,从而有效地解决了周波跳跃和局部极小的难题;③先验知识的约束和地震数据的预处理是全波形反演成功应用于苏里格气田气藏检测的关键。  相似文献   
9.
名词短语一直是中外语言学领域的重要研究对象,近年来在自然语言处理领域也受到了研究者的持续关注。英文方面,已建立了一定规模的名词短语语义关系知识库。但迄今为止,尚未建立相应或更大规模的描述名词短语语义关系的中文资源。该文借鉴国内外诸多学者对名词短语语义分类的研究成果,对大规模真实语料中的基本复合名词短语实例进行试标注与分析,建立了中文基本复合名词短语语义关系体系及相应句法语义知识库,该库能够为中文基本复合名词短语句法语义的研究提供基础数据资源。目前该库共含有18 281条高频基本复合名词短语,每条短语均标注了语义关系、短语结构及是否指称实体等信息,每条短语包含的两个名词还分别标注了语义类信息。语义类信息基于北京大学《现代汉语语义词典》。基于该知识库,该文还做了基本复合名词短语句法语义的初步统计与分析。  相似文献   
10.
为了更加准确地检测出图像中的显著性目标,提出了多先验融合的显著性目标检测算法。针对传统中心先验对偏离图像中心的显著性目标会出现检测失效的情况,提出在多颜色空间下求显著性目标的最小凸包交集来确定目标的大致位置,以凸包区域中心计算中心先验。同时通过融合策略将凸包区域中心先验、颜色对比先验和背景先验融合并集成到特征矩阵中。最后通过低秩矩阵恢复模型生成结果显著图。在公开数据集MSRA1000和ESSCD上的仿真实验结果表明,MPLRR能够得到清晰高亮的显著性目标视觉效果图,同时F,AUC,MAE等评价指标也比现有的许多方法有明显提升。  相似文献   
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