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81.
Plasma cholesterol and triglyceride levels were determined, on each of two AutoAnalyzer systems in 11 healthy subjects, weekly over a 10-week and monthly over a 12-month period. Analytical variation was 1–2% for cholesterol and 2–5% for triglyceride. Cholesterol and triglyceride values on frozen quality control serum pools were not indicative of absolute values on fresh plasma. Even though the two AutoAnalyzer systems averaged within 1–2 mg/dl for triglyceride and cholesterol on the serum quality control pools during the 12-month period, the two systems differed by 7–8 mg/dl on fresh or frozen plasma samples. The coefficient of physiological variation on the 10 weekly samples averaged 5% (range 3–10%) for plasma cholesterol and 18% (range 9–27%) for plasma triglyceride. Analysis of the monthly samples suggested significant (P<0.05) seasonal trends: cholesterol was highest in the winter months and lowest in October, whereas triglyceride was highest in January and February and lowest in May and December. We conclude that intra-individual variation can be an important source of error in attempting to make a genetic diagnosis of hyperlipidemia and/or in evaluating hypolipidemic regimens in a given subject.  相似文献   
82.
Delayed Information and Action in On-Line Algorithms   总被引:1,自引:0,他引:1  
Most on-line analysis assumes that, at each time step, all relevant information up to that time step is available and a decision has an immediate effect. In many on-line problems, however, the time when relevant information is available and the time a decision has an effect may be decoupled. For example, when making an investment, one might not have completely up-to-date information on market prices. Similarly, a buy or sell order might only be executed some time in the future. We introduce and explore natural delayed models for several well-known on-line problems. Our analyses demonstrate the importance of considering timeliness in determining the competitive ratio of an on-line algorithm. For many problems, we demonstrate that there exist algorithms with small competitive ratios even when large delays affect the timeliness of information and the effect of decisions.  相似文献   
83.
When using standard control charts, typically several parameters need to be estimated. For the usual sample sizes, this is known to affect the performance of the chart. Here we present simple corrections to solve this problem. As a basis, we use existing factors which are widely used for the traditional charts. The advantage of the new proposals is that a clear link is made to the actual performance characteristics of the chart.  相似文献   
84.
Many bioinformatics applications construct classifiers that are validated in experiments that compare their results to known ground truth over a corpus. In this paper, we introduce an approach for exploring the results of such classifier validation experiments, focusing on classifiers for regions of molecular surfaces. We provide a tool that allows for examining classification performance patterns over a test corpus. The approach combines a summary view that provides information about an entire corpus of molecules with a detail view that visualizes classifier results directly on protein surfaces. Rather than displaying miniature 3D views of each molecule, the summary provides 2D glyphs of each protein surface arranged in a reorderable, small‐multiples grid. Each summary is specifically designed to support visual aggregation to allow the viewer to both get a sense of aggregate properties as well as the details that form them. The detail view provides a 3D visualization of each protein surface coupled with interaction techniques designed to support key tasks, including spatial aggregation and automated camera touring. A prototype implementation of our approach is demonstrated on protein surface classifier experiments.  相似文献   
85.
Forschung im Ingenieurwesen - Die Reib- und Verschleißeigenschaften trockenlaufender Friktionspaarungen werden mithilfe neuer Methoden bestimmt, um deren Schädigungs- und...  相似文献   
86.
Forschung im Ingenieurwesen - In automated vehicles, the collaboration of human drivers and automated systems plays a&nbsp;decisive role in road safety, driver comfort, and acceptance of...  相似文献   
87.
Personalized, interactive news on the Web   总被引:2,自引:0,他引:2  
We present Krakatoa Chronicle, an interactive, personalized newspaper on the World Wide Web implemented as a Java applet. The newspaper is similar in appearance to newspapers in the real world, with a multi-column layout and justified text. At the same time, it provides various interaction techniques for browsing the content of articles, giving relevance feedback, and dynamically changing layout. As users interact with the system, individual ‘user profiles’ are built up at the webserver site. These are used to tailor the newspaper's content and layout to each user's declared and inferred preferences. The system allows for a balancing of personal and community interests, allowing the user to navigate through a space of newspapers corresponding to a range of viewpoints.  相似文献   
88.
Miniaturization is a trend in mechanical engineering, in which 3D mechanical structures are required. Consequences are changed production and design processes. Furthermore micro-specific design requires in-depth knowledge of production technology. One successful means for ensuring the consideration of these restrictions are design rules. However, many aspects of design relevant knowledge are not restrictive and cannot be represented by design rules. The authors propose the application of design patterns, which represent problem- and solution-oriented knowledge. A pattern describes the abstract solution for a frequently occurring problem in a specific context. This approach was first introduced to architecture and then adapted to software engineering. Also first moves were made to use pattern languages in engineering design. The authors propose design patterns to represent design knowledge for microsystem technologies. As methodological means of support, a pattern lifecycle activity model and subordinate methods are presented.  相似文献   
89.
The Local Analysis and Prediction System (LAPS) is modified to ingest Meteosat Second Generation (MSG) data for cloud analysis. A first study is conducted to test the actual performance of the weather analysis software after new satellite bands are introduced. Results show that the system provides high quality cloud products such as cloud mask, cloud top height and cloudiness. A comparison with products from EUMETSAT’s Nowcasting SAF shows a general underestimation of the LAPS product although the results are not conclusive. The study shows the potential of MSG data in refining the mesoscale analyses produced by LAPS. Moreover the software tools, based on open source codes for geolocation and geographical information systems, written for the transformation of MSG data into input files for LAPS have demonstrated a great flexibility and ease of use. The study opens up an avenue for successive validation and refinement of the analyses together with their improved implementation for operational nowcasting and very short range forecasting applications.  相似文献   
90.
We determined oropharyngeal biofilm removal from silicone rubber voice prostheses in an artificial throat after perfusion with different commercially available dairy products, including buttermilk, Lactobacillus casei Shirota fermented milk (Yakult, Yakult Netherlands BV, Almere, The Netherlands), low-fat milk, and three types of yogurt. Buttermilk removed both yeasts and bacteria from biofilms on voice prostheses, but this was not observed with a pasteurized buttermilk product. Some of the other products, most notably Yakult fermented milk drink, reduced the number of bacteria, whereas growth of yeasts in the biofilms was not inhibited. This study demonstrates that there may be health benefits associated with the consumption of certain dairy products when applied to the upper digestive tract.  相似文献   
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