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91.
Combining knowledge from different sources 总被引:1,自引:1,他引:0
Ewa Straszecka 《Expert Systems》2010,27(1):40-52
Abstract: The present paper deals with the problem of an assessment of symptoms in medical diagnosis. A unified interpretation of symptoms is necessary to estimate their significance in a diagnosis. Yet, even if they are properly defined, different evaluations of them based on experts' knowledge or statistical estimation are possible. The present study aims at combining evaluations that may originate from an expert or can be found from statistical features of the data, as well as those determined for 'easy' and 'difficult' diagnostic cases. A model of diagnostic inference is proposed in the framework of the Dempster–Shafer theory extended for fuzzy focal elements. The basic probability assignment defined in this theory estimates weights of symptoms. Two basic probability assignments can be created and then combined. In this way weights of symptoms represent knowledge common for two kinds of data or obtained from an expert and from data. Thus, a combination of heuristics and data mining results becomes possible. An algorithm of the basic probability assignment calculation is suggested and tested for medical data: a database from the internet and individually gathered data. 相似文献
92.
The paper addresses the problem of multi-slot just-in-time scheduling. Unlike the existing literature on this subject, it
studies a more general criterion—the minimization of the schedule makespan rather than the minimization of the number of slots
used by schedule. It gives an O(nlog 2
n)-time optimization algorithm for the single machine problem. For arbitrary number of m>1 identical parallel machines it presents an O(nlog n)-time optimization algorithm for the case when the processing time of each job does not exceed its due date. For the general
case on m>1 machines, it proposes a polynomial time constant factor approximation algorithm. 相似文献
93.
94.
Marcin Miłkowski 《Minds and Machines》2009,19(4):465-475
In Darwin’s Dangerous Idea, Daniel Dennett claims that evolution is algorithmic. On Dennett’s analysis, evolutionary processes are trivially algorithmic
because he assumes that all natural processes are algorithmic. I will argue that there are more robust ways to understand
algorithmic processes that make the claim that evolution is algorithmic empirical and not conceptual. While laws of nature
can be seen as compression algorithms of information about the world, it does not follow logically that they are implemented
as algorithms by physical processes. For that to be true, the processes have to be part of computational systems. The basic
difference between mere simulation and real computing is having proper causal structure. I will show what kind of requirements
this poses for natural evolutionary processes if they are to be computational. 相似文献
95.
Tomasz Fałat Kazimierz Friedel Norman Marenco Stephan Warnat 《Microsystem Technologies》2009,15(1):181-190
The current paper focuses on several mechanical aspects of a waferlevel packaging approach using a direct face-to-face Chip-to-Wafer
(C2W) bonding of a MEMS device on an ASIC substrate wafer. Requirements of minimized inherent stress from packaging and good
decoupling from forces applied in manufacturing and application are discussed with particular attention to the presence of
through-silicon vias (TSV) in the substrate wafer. The paper deals with FEM analysis of temperature excursion, pressure during
molding, materials used and handling load influence on mechanical stress within the TSV system and on wafer level, which can
be large enough to disintegrate the system. 相似文献
96.
97.
In this paper a novel Tensor-Based Image Segmentation Algorithm (TBISA) is presented, which is dedicated for segmentation of colour images. A purpose of TBISA is to distinguish specific objects based on their characteristics, i.e. shape, colour, texture, or a mixture of these features. All of those information are available in colour channel data. Nonetheless, performing image analysis on the pixel level using RGB values, does not allow to access information on texture which is hidden in relation between neighbouring pixels. Therefore, to take full advantage of all available information, we propose to incorporate the Structural Tensors as a feature extraction method. It forms enriched feature set which, apart from colour and intensity, conveys also information of texture. This set is next processed by different classification algorithms for image segmentation. Quality of TBISA is evaluated in a series of experiments carried on benchmark images. Obtained results prove that the proposed method allows accurate and fast image segmentation. 相似文献
98.
The aim of this study was to investigate whether there are differences in technique between young adults with and without musculoskeletal symptoms when using a mobile phone for texting and whether there are differences in muscle activity and kinematics between different texting techniques. A total of 56 young adults performed a standardised texting task on a mobile phone. Their texting techniques were registered using an observation protocol. The muscular activity in six muscles in the right forearm/hand and both shoulders were registered by surface electromyography and the thumb abduction/adduction and flexion/extension were registered using a biaxial electrogoniometer. Differences in texting techniques were found between the symptomatic and the asymptomatic group, with a higher proportion of sitting with back support and forearm support and with a neutral head position in the asymptomatic group. Differences in muscle activity and kinematics were also found between different texting techniques. The differences in texting technique between symptomatic and asymptomatic subjects cannot be explained by them having symptoms but may be a possible contribution to their symptoms. STATEMENT OF RELEVANCE: There has been a dramatically increased use of mobile phones for texting especially among young people during the last years. A better understanding of the physical exposure associated with the intensive use is important in order to prevent the development of musculoskeletal disorders and decreased work ability related to this use. 相似文献
99.
We propose an efficient algorithm for computing a unit lower triangular n×n matrix with prescribed singular values of O(n
2) cost. This is a solution of the question raised by N. J. Higham in [4, Problem 26.3, p. 528].
Received July 21, 1999; revised November 4, 1999 相似文献
100.
The paper describes the new development programme of the Polish information infrastructure. The programme, called in Polish PIONIER: (English—PIONEER) Polish Optical Internet, Advanced Applications, Services and Technologies for the Information Society, has been proposed to the Polish State Committee for Scientific Research and has been accepted. The aim of the programme is to create an advanced infrastructure together with tools, services and applications available to the entire scientific community and eventually to government and local administrations as well as society in general. Services and applications are expected to appear as selected pilot realizations in order to verify deployed technologies. Some of the pilot realizations and testbeds are also presented in the paper. 相似文献