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排序方式: 共有1185条查询结果,搜索用时 15 毫秒
1.
15年前柏林城市规划的定义与现在完全不同.至今,柏林的两个组成部分还有不同的规划理念:一方面,在西柏林.规划严格控制在划定的50平方公里两百万居民的边线范围内;另一方面,在前东德首都的东柏林.所有活动集中在有限的中心地区以展示其首都功能.而柏林周边地区没有包含在任何区域规划系统内.这样的结果导致东、西柏林以及柏林同周边乡镇有完全不同的生活方式. 相似文献
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4.
Howard Kenneth I.; Krause Merton S.; Vessey John T. 《Canadian Metallurgical Quarterly》1994,31(2):302
The immediate goal of any clinical trial is to determine to which of a specified set of treatments future patients are to be assigned, particularly when analyzing data from clinical trials. When the outcome distributions of Experimental (E) and Control (C) treatments overlap, differences between treatment group means are not conclusive and may not be very informative, so a display of the overlapped frequency distributions and a summary measure of the probability of a random patient in E doing better than a random patient in C are needed. When outcome distributions overlap, the question of statistical model becomes crucial even when there are very significant differences between group means and very large effect sizes. Determining what patient variables interact with treatments is the route to optimal assignment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
R. Kornhuber R. Krause O. Sander P. Deuflhard S. Ertel 《Computing and Visualization in Science》2008,11(1):3-15
The purpose of the paper is to apply monotone multigrid methods to static and dynamic biomechanical contact problems. In space,
a finite element method involving a mortar discretization of the contact conditions is used. In time, a new contact-stabilized
Newmark scheme is presented. Numerical experiments for a two body Hertzian contact problem and a biomechanical application
are reported.
This work was supported by the DFG Research Center Matheon. 相似文献
6.
Norman Fenton Martin Neil William Marsh Peter Hearty Łukasz Radliński Paul Krause 《Empirical Software Engineering》2008,13(5):499-537
Standard practice in building models in software engineering normally involves three steps: collecting domain knowledge (previous
results, expert knowledge); building a skeleton of the model based on step 1 including as yet unknown parameters; estimating
the model parameters using historical data. Our experience shows that it is extremely difficult to obtain reliable data of
the required granularity, or of the required volume with which we could later generalize our conclusions. Therefore, in searching
for a method for building a model we cannot consider methods requiring large volumes of data. This paper discusses an experiment
to develop a causal model (Bayesian net) for predicting the number of residual defects that are likely to be found during
independent testing or operational usage. The approach supports (1) and (2), does not require (3), yet still makes accurate
defect predictions (an R
2 of 0.93 between predicted and actual defects). Since our method does not require detailed domain knowledge it can be applied
very early in the process life cycle. The model incorporates a set of quantitative and qualitative factors describing a project
and its development process, which are inputs to the model. The model variables, as well as the relationships between them,
were identified as part of a major collaborative project. A dataset, elicited from 31 completed software projects in the consumer
electronics industry, was gathered using a questionnaire distributed to managers of recent projects. We used this dataset
to validate the model by analyzing several popular evaluation measures (R
2, measures based on the relative error and Pred). The validation results also confirm the need for using the qualitative factors
in the model. The dataset may be of interest to other researchers evaluating models with similar aims. Based on some typical
scenarios we demonstrate how the model can be used for better decision support in operational environments. We also performed
sensitivity analysis in which we identified the most influential variables on the number of residual defects. This showed
that the project size, scale of distributed communication and the project complexity cause the most of variation in number
of defects in our model. We make both the dataset and causal model available for research use. 相似文献
7.
India ink skin markings allow consistently reproducible radiation field setups. The authors report a case in which a facial tattoo was applied with an injection, resulting in permanent "black eyes." The vaccination technique has not been associated with this complication. 相似文献
8.
JR Krause 《Canadian Metallurgical Quarterly》1977,70(9):1072-4, 1079
Amyloid involvement of the bone marrow is not commonly diagnosed before necropsy. Paraffin sections of the trephine bone biopsy specimen are superior to marrow aspiration cell smears for the antemortem diagnosis. Thirteen cases of amyloidosis were diagnosed from the bone biopsy specimen during a ten-year period. Amyloid was detected in only two of the corresponding aspirates. Three morphologic patterns of marrow involvement were found: vascular, focal extravascular/perivascular, and diffuse. Five (38%) of the cases were associated with multiple myeloma. An abnormal immunoglobulin was detected in the serum or urine or both in ten of 11 cases when determined. Although the bone marrow may not be the best site for the diagnosis of amyloidosis, it should not be neglected and marrow biopsies taken for other diagnostic reasons may "incidentally" reveal amyloid. Amyloidosis should be included in the list of non-primary hematologic conditions of the bone marrow in which the trephine biopsy may prove useful for diagnosis. 相似文献
9.
Strength and fatigue of silica optical fibers 总被引:4,自引:0,他引:4
After a brief review of early lightguide work, the authors assess advances since the mid-1970s. They note important work on strength distributions and procedures for improving strength. This is followed by a discussion of long-length strength, prooftesting and splicing. Flaw character is studied along with strength degradation, fatigue limits, aging and fatigue, and hermetic coatings 相似文献
10.
The present study aims at investigating the absorption behaviour of acetylated (AFBPI) and non-acetylated (FBPI) faba bean protein isolate at a sunflower oil-water interface in dependence on different environmental conditions (protein concentration, pectin addition). 相似文献