中文基本复合名词短语语义关系体系及知识库构建

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。     

一种结合区域检测和语义分割的SLAM技术

提出一种结合区域检测和语义分割的即时定位和建图（SLAM）技术，通过引入高精度图像描述子SIFT来实现前端视觉里程计（VO）过程中帧间像素匹配的精度。为了降低引入操作带来的计算复杂度，设计一个实时区域检测算法，在相邻帧间检测大致相似的ROI(Region of Interest)关键区域，使得SIFT描述子的提取和匹配只在ROI区域内完成，其余区域仍旧采用精度略低、效率更高的ORB算子。同时，为了提高后端BA(Bundle Adjustment)的精度，减少累积误差，结合语义图，在原有的基本投影误差函数上添加一个语义误差。该语义图采用实时语义分割算法完成，同时只针对ROI区域进行分割。通过与原SLAM方案对比实验，表明本文提出的方法，在提高一定精度的同时，仍能满足SLAM实时定位和建图的要求。最后，在电力作业场景下验证了该方案的效果。     

粒子群属性聚类的位置隐私保护

针对基于位置服务中连续查询情况下，用户自身属性信息很容易被攻击者获取，并通过关联获得用户位置隐私的情况，提出了一种利用粒子群聚类加速相似属性用户寻找，并由相似属性匿名实现用户位置泛化的隐私保护方法。该方法利用位置隐私保护中常用的可信中心服务器，通过对发送到中心服务器中的查询信息进行粒子群属性聚类，在聚类的过程中加速相似属性用户的寻找过程，由相似属性用户完成位置泛化，以此实现位置隐私保护。实验结果证明，这种基于粒子群属性聚类的隐私保护方法具有高于同类算法的隐私保护能力，以及更快的计算处理速度。     

基于多注意力长短时记忆的实体属性情感分析

属性情感分析是细粒度的情感分类任务。针对传统神经网络模型无法准确构建属性情感特征的问题，提出了一种融合多注意力和属性上下文的长短时记忆（LSTM-MATT-AC）神经网络模型。在双向长短时记忆（LSTM）的不同位置加入不同类型的注意力机制，充分利用多注意力机制的优势，让模型能够从不同的角度关注句子中特定属性的情感信息，弥补了单一注意力机制的不足；同时，融合双向LSTM独立编码的属性上下文语义信息，获取更深层次的情感特征，有效识别特定属性的情感极性；最后在SemEval2014 Task4和Twitter数据集上进行实验，验证了不同注意力机制和独立上下文处理方式对属性情感分析模型的有效性。实验结果表明，模型在Restaurant、Laptop和Twitter领域数据集上的准确率分别达到了80.6%、75.1%和71.1%，较之前基于神经网络的情感分析模型在准确率上有了进一步的提高。     

A hybrid knowledge and ensemble classification approach for prediction of venous thromboembolism

Clinical narratives such as progress summaries, lab reports, surgical reports, and other narrative texts contain key biomarkers about a patient's health. Evidence-based preventive medicine needs accurate semantic and sentiment analysis to extract and classify medical features as the input to appropriate machine learning classifiers. However, the traditional approach of using single classifiers is limited by the need for dimensionality reduction techniques, statistical feature correlation, a faster learning rate, and the lack of consideration of the semantic relations among features. Hence, extracting semantic and sentiment-based features from clinical text and combining multiple classifiers to create an ensemble intelligent system overcomes many limitations and provides a more robust prediction outcome. The selection of an appropriate approach and its interparameter dependency becomes key for the success of the ensemble method. This paper proposes a hybrid knowledge and ensemble learning framework for prediction of venous thromboembolism (VTE) diagnosis consisting of the following components: a VTE ontology, semantic extraction and sentiment assessment of risk factor framework, and an ensemble classifier. Therefore, a component-based analysis approach was adopted for evaluation using a data set of 250 clinical narratives where knowledge and ensemble achieved the following results with and without semantic extraction and sentiment assessment of risk factor, respectively: a precision of 81.8% and 62.9%, a recall of 81.8% and 57.6%, an F measure of 81.8% and 53.8%, and a receiving operating characteristic of 80.1% and 58.5% in identifying cases of VTE.     

互联网Web前端应用中的问题分析

随着Web的发展,在该领域存在的问题也逐渐显露出现,为了从根本上解决Web前端应用过程中存在的问题,需要对Web前端设计进行系统化分析。近年来,Web前端在实际应用过程中因结构设计不完善出现了很多问题,严重影响Web工作的正常运转,针对Web前端问题而提出的研究与防范措施迫在眉睫。目前,基于Web前端结构设计工作的特殊性,可以看出Web前端设计项目至关重要。文章主要介绍了Web前端的具体结构设计以及Web前端在实际应用过程中存在的问题,并提出了相应的解决对策。     

Inverse reinforcement learning-based time-dependent A* planner for human-aware robot navigation with local vision

In an environment where robots coexist with humans, mobile robots should be human-aware and comply with humans' behavioural norms so as to not disturb humans' personal space and activities. In this work, we propose an inverse reinforcement learning-based time-dependent A* planner for human-aware robot navigation with local vision. In this method, the planning process of time-dependent A* is regarded as a Markov decision process and the cost function of the time-dependent A* is learned using the inverse reinforcement learning via capturing humans' demonstration trajectories. With this method, a robot can plan a path that complies with humans' behaviour patterns and the robot's kinematics. When constructing feature vectors of the cost function, considering the local vision characteristics, we propose a visual coverage feature for enabling robots to learn from how humans move in a limited visual field. The effectiveness of the proposed method has been validated by experiments in real-world scenarios: using this approach robots can effectively mimic human motion patterns when avoiding pedestrians; furthermore, in a limited visual field, robots can learn to choose a path that enables them to have the larger visual coverage which shows a better navigation performance.     

Mímir: An open-source semantic search framework for interactive information seeking and discovery

Semantic search is gradually establishing itself as the next generation search paradigm, which meets better a wider range of information needs, as compared to traditional full-text search. At the same time, however, expanding search towards document structure and external, formal knowledge sources (e.g. LOD resources) remains challenging, especially with respect to efficiency, usability, and scalability.This paper introduces Mímir—an open-source framework for integrated semantic search over text, document structure, linguistic annotations, and formal semantic knowledge. Mímir supports complex structural queries, as well as basic keyword search.Exploratory search and sense-making are supported through information visualisation interfaces, such as co-occurrence matrices and term clouds. There is also an interactive retrieval interface, where users can save, refine, and analyse the results of a semantic search over time. The more well-studied precision-oriented information seeking searches are also well supported.The generic and extensible nature of the Mímir platform is demonstrated through three different, real-world applications, one of which required indexing and search over tens of millions of documents and fifty to hundred times as many semantic annotations. Scaling up to over 150 million documents was also accomplished, via index federation and cloud-based deployment.     

定子扇形片复合模设计

分析零件自身的特点和成形难点,针对成形难点制定相应的解决对策,结合类似模具在以往设计、加工、组装、使用和维护过程中遇到的问题,对定子扇形片复合模设计难点的解决方法及相关注意事项分别进行了介绍,模具经多次调试已顺利投入生产,对类似零件的模具设计具有一定的参考作用。     

Semantically enriched Massive Open Online Courses (MOOCs) platform

Massive Open Online Courses (MOOCs) are becoming an essential source of information for both students and teachers. Noticeably, MOOCs have to adapt to the fast development of new technologies; they also have to satisfy the current generation of online students. The current MOOCs’ Management Systems, such as Coursera, Udacity, edX, etc., use content management platforms where content are organized in a hierarchical structure. We envision a new generation of MOOCs that support interpretability with formal semantics by using the SemanticWeb and the online social networks. Semantic technologies support more flexible information management than that offered by the current MOOCs’ platforms. Annotated information about courses, video lectures, assignments, students, teachers, etc., can be composed from heterogeneous sources, including contributions from the communities in the forum space. These annotations, combined with legacy data, build foundations for more efficient information discovery in MOOCs’ platforms. In this article we review various Collaborative Semantic Filtering technologies for building Semantic MOOCs’ management system, then, we present a prototype of a semantic middle-sized platform implemented at Western Kentucky University that answers these aforementioned requirements.