基于互信息的颅脑MR影像序列的三维配准

医学图像配准具有重要的临床应用价值,并一直是医学图像处理领域的热点研究问题。基于互信息的配准方法由于自动化程度高和配准精度高的优点而被广泛应用于三维医学图像配准;但是,也存在着数据量大、计算速度慢的问题。采用归一化互信息测度,并将一种新的正交优化技术应用于颅脑MR影像序列的三维配准,旨在缩短处理时间。将该方法与使用传统优化算法的配准方法作了比较,实验结果表明,提出的方法能够显著提高配准速度,且不降低配准精度。     

Ontology-driven document enrichment: principles, tools and applications

In this paper, we present an approach to document enrichment, which consists of developing and integrating formal knowledge models with archives of documents, to provide intelligent knowledge retrieval and (possibly) additional knowledge-intensive services, beyond what is currently available using “standard” information retrieval and search facilities. Our approach is ontology-driven, in the sense that the construction of the knowledge model is carried out in a top-down fashion, by populating a given ontology, rather than in a bottom-up fashion, by annotating a particular document. In this paper, we give an overview of the approach and we examine the various types of issues (e.g. modelling, organizational and user interface issues) which need to be tackled to effectively deploy our approach in the workplace. In addition, we also discuss a number of technologies we have developed to support ontology-driven document enrichment and we illustrate our ideas in the domains of electronic news publishing, scholarly discourse and medical guidelines.     

膜法富氧技术及其应用研究

介绍了作者在膜法富氧技术方面的研究进展，并将膜法与其他制氧方法进行了比较，最后讨论了膜法富氧技术目前的有关应用，着重研究了膜法富氧在有色金属冶炼，硅酸盐窑炉，化铁炉，加热炉，医疗保健和柴油机增氧等方面的典型应用。     

平移不变小波医学图像融合方法

针对传统小波变换融合算法对细节信息的丢失问题,提出了一种新的基于平移不变小波变换的医学图像融合算法,采用灰度加权平均法进行低频部分融合;高频部分采用基于梯度能量的加权融合规则。实验结果表明,与传统的小波变换方法相比,文中方法融合效果更加理想,较多地继承了两幅源图像的重要信息,更好地描述了图像的细节部分,更具有实用性。     

区域自识别医用观片灯控制系统设计

基于嵌入式控制技术,提出一种具有区域自识别功能的新型医用观片灯系统结构。该系统以超高亮白光LED构成分布均匀的LED阵列,通过嵌入式控制器识别X光片的规格及覆盖区域,并控制该区域的LED灯阵列发光。本系统所采用的分区LED灯光控制技术不仅可以有效节约电能,大幅延长观片灯寿命,而且还能改善医务工作者观察的舒适度。     

Hybrid watermarking of medical images for ROI authentication and recovery

Medical image data require strict security, confidentiality and integrity. To achieve these stringent requirements, we propose a hybrid watermarking method which embeds a robust watermark in the region of non-interest (RONI) for achieving security and confidentiality, while integrity control is achieved by inserting a fragile watermark into the region of the interest (ROI). First the information to be modified in ROI is separated and is inserted into RONI, which later is used in recovery of the original ROI. Secondly, to avoid the underflow and overflow, a location map is generated for embedding the watermark block-wise by leaving the suspected blocks. This avoids the preprocessing step of histogram modification. The image visual quality, as well as tamper localization, is evaluated. We use weighted peak signal to noise ratio for measuring image quality of watermarked images. Experimental results show that the proposed method outperforms the existing hybrid watermarking techniques.     

Collaboration processes,outcomes, challenges and enablers of distributed clinical communities of practice

Modern healthcare's need for knowledge sharing and bridging the research–practice gap requires new forms of collaboration, in which clinicians of varying clinical and research expertise work together over geographical and organisational borders. To support such distributed communities of practice (CoPs), an understanding of their collaboration processes, outcomes, challenges and enablers is needed. The article examines these issues through a case study of a long-running CoP, the Swedish Oral Medicine Network (SOMNet). SOMNet's main form of collaboration is monthly telephone conference meetings centred on case consultations. Cases are submitted by the clinicians via a Web-based system. The methods used were interviews, observations, and a questionnaire. The work adds to previous research by studying a distributed CoP explicitly focused on supporting the transfer of scientific results from researchers to practitioners. We found that the regular meetings give a rhythm to the community. The centrality of cases means an immediate benefit for the submitter while the community is provided an authentic context for learning. SOMNet yields opportunities for help and learning for diverse expertise levels; the type of benefits is affected by the participant's degree of oral medicine knowledge and collaboration involvement. There are challenges in accommodating varying levels of expertise and encouraging those less experienced to participate. Enablers of the collaboration include the participation of experts, meeting facilitators and well-adapted ITs.     

Denotation and connotation in the human – computer interface: The ‘Save as …’ command

This paper presents a semiotic technique as a means of exploring meaning and understanding in interface design and use. This is examined through a study of the interaction between the ‘file’ metaphor and ‘save as’ command metaphor. The behaviour of these (from a functional or computational basis) do not exactly match, or map onto, the meaning of the metaphor. We examine both the denotation of a term to the user, i.e. its literal meaning to that person, and the term's connotations, i.e. any other meanings associated with the term. We suggest that the technique applied is useful in predicting future problems with understanding the use of metaphor at the interface and with designing appropriate signification for human-computer interaction. Variation in connotation was expected but a more fundamental difference in denotation was also uncovered. Moreover, the results clearly demonstrate that consistency in the denotation of a term is critical in achieving a good user understanding of the command.     

国内外保险投资和保险定价研究的发展评述

回顾了国内外近年来保险投资和保险定价研究的主要发展,着重评述了最优控制理论、随机微分博弈理论在保险投资与最优保险定价中的运用以及保险定价中如何融入资本分配因素,提出了有待进一步研究的问题以及对于我国保险投资和保险定价研究工作的意义。     

水利高职教育顶岗实习环节安全风险管理对策

水利高职教育顶岗实习是教学过程的重要环节。通过分析顶岗实习环节的安全风险,提出了高职教育顶岗实习环节的安全风险管理对策,明确指出高职院校除了应重视安全教育外,还应加强实习风险管理,推广实习责任保险。