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Adverse effects of excessive cutaneous exposure to solar radiation are hazards of considerable importance. As public health measures, new attitudes about sunbathing and new practices to counteract those adverse effects, especially for high-risk individuals, appear warranted.  相似文献   
34.
We present a general approach to the prediction of 3-D foldsof protein chains from their amino acid sequences. The approachis based on the use of the self-consistent molecular field theoryfor long-range interactions, the use of 1-D statistical mechanicsfor short-range interactions and on the discovery that thereis and should only be a relatively small discrete set of foldingpatterns. This makes it possible to examine the full varietyof ‘potentially stable’ folds and to determine thethermodynamically stable structure. In this paper, we give thegeneral theoretical background of the approach. The encouragingresults of the application of this approach to ß-domainsare described in another paper.  相似文献   
35.
Overlaps in Requirements Engineering   总被引:4,自引:0,他引:4  
Although overlap between specifications—that is the incorporation of elements which designate common aspects of the system of concern—is a precondition for specification inconsistency, it has only been a side concern in requirements engineering research. This paper is concerned with overlaps. It defines overlap relations in terms of specification interpretations, identifies properties of these relations which are derived from the proposed definition, shows how overlaps may affect the detection of inconsistency; shows how specifications could be rewritten to reflect overlap relations and still be amenable to consistency checking using theorem proving; analyses various methods that have been proposed for identifying overlaps with respect to the proposed definition; and outlines directions for future research.  相似文献   
36.
We present several algorithms suitable for analysis of broadcast video. First, we show how wavelet analysis of frames of video can be used to detect transitions between shots in a video stream, thereby dividing the stream into segments. Next we describe how each segment can be inserted into a video database using an indexing scheme that involves a wavelet-based “signature.” Finally, we show that during a subsequent broadcast of a similar or identical video clip, the segment can be found in the database by quickly searching for the relevant signature. The method is robust against noise and typical variations in the video stream, even global changes in brightness that can fool histogram-based techniques. In the paper, we compare experimentally our shot transition mechanism to a color histogram implementation, and also evaluate the effectiveness of our database-searching scheme. Our algorithms are very efficient and run in realtime on a desktop computer. We describe how this technology could be employed to construct a “smart VCR” that was capable of alerting the viewer to the beginning of a specific program or identifying  相似文献   
37.
The time and costs involved in connecting the IT systems of two companies impact the actual formation of business relationships. A flexible infrastructure for process management is instrumental for rapid and cost-effective B2B integration. One dimension of flexibility that system integrators identify as critical is node-level interaction. In this paper, we discuss the findings of the Nile project on B2B process integration. In particular, we present the methodology defined in Nile for the semi-automatic reconciliation of node-level incompatibilities.  相似文献   
38.
In many binary medical classification problems, the cost of misclassifying one category is higher than the other, and in these applications it is desirable to employ a classifier with selective sensitivity or specificity. This work explores the utility of a fuzzy multi–criteria function for performance evaluation during knowledge–based medical classification and prediction. The method presented here uses fuzzy optimization to combine the sensitivity, specificity, and accuracy of classification as goals in a single objective function. This approach is used to assign flexible goals, which can be used to maximize the outcome in terms of each one of the goals. The proposed approach significantly increases the sensitivity and the specificity while maintaining or increasing accuracy. The versatility of the method is further exploited in a multi-model approach, using individual structures of multi-objective optimization of sensitivity and specificity separately, and then combining their outcomes through a decision-making module. Among various medical benefits derived from applying this technique, the divergent feature sets selected by high sensitivity and specificity models lend insight into factors more integrally connected to what causes risk of death for patients.  相似文献   
39.
The latest Internet markup languages support the representation of structured information and vector graphics. In this paper we describe how these languages can be used to publish software engineering diagrams on the Internet. We introduce BOX, a portable, distributed and interoperable approach to browsing UML models with off‐the‐shelf technology. Our approach to browsing UML models leverages XML and related specifications, such as the Document Object Model (DOM), the XML Metadata Interchange (XMI) and the Vector Markup Language (VML). BOX translates a UML model that is represented in XMI into VML. VML can be directly displayed in Internet browsers, such as Microsoft's Internet Explorer 5. BOX enables software engineers to access and review UML models without the need to purchase licenses of tools that produced the models. BOX has been successfully evaluated in two industrial case studies. The case studies used BOX to make extensive domain and enterprise object models available to a large number of stakeholders over corporate intranets and the Internet. We show how XML and the BOX architecture can be applied to other software engineering notations. We also argue that the approach taken in BOX can be applied to other domains that have already started to adopt XML and have a need for graphic representation of XML information. These include browsing gene sequences, chemical molecule structures and conceptual knowledge representations. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
40.
This paper describes the results of a summative evaluation conducted to explore the usability and acceptability of an automated telephone-based technology, designed and developed as a screening tool for mental health disorders in the workplace. The system screens employees for symptoms and subsequently provides educational information and referrals to improve mental health and enhance productivity. The qualitative evaluation was a sub-study of a larger randomized controlled trial (RCT). We conducted in-depth interviews with 15 individuals who participated in the RCT and had used the system. A phenomenological theoretical framework was utilized to analyze the narrative data. Results indicated that participants had mostly positive experience with the system and perceived it as a confidential program that allowed them to reflect on their symptoms without inhibition, fear of judgment or embarrassment. We also learned that asking mere questions about mental health symptoms can be a positive, instructive and possibly a restorative experience. There is a likelihood that for many participants, exposure to questions about their emotional and mental distress validated their feelings about their symptoms and was sufficiently compelling to promote help-seeking behavior. This evaluation study demonstrates that computers can be utilized in the workplace as effective screening and educational tools to improve employees’ mental health.  相似文献   
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