149 research outputs found
Using level-2 fuzzy sets to combine uncertainty and imprecision in fuzzy regions
In many applications, spatial data need to be considered but are prone to uncertainty or imprecision. A fuzzy region - a fuzzy set over a two dimensional domain - allows the representation of such imperfect spatial data. In the original model, points of the fuzzy region where treated independently, making it impossible to model regions where groups of points should be considered as one basic element or subregion. A first extension overcame this, but required points within a group to have the same membership grade. In this contribution, we will extend this further, allowing a fuzzy region to contain subregions in which not all points have the same membership grades. The concept can be used as an underlying model in spatial applications, e.g. websites showing maps and requiring representation of imprecise features or websites with routing functions needing to handle concepts as walking distance or closeby
Single use droplet Based Microfluidics – Screening Tools for Biotechnology and Life-Sciences
In the recent years droplet-based microfluidic techniques were developed and used for various screening purposes mainly in the field of life-sciences and biotechnology. Therefore, droplet volumes in a range from pL to μL were used and different technology platforms were necessary to produce the required fluidic devices which made of various materials. Traditionally, lithography combined with etching processes were used to produce precise glass or silicon devices. But, hot embossing and injection molding techniques are better suited for the production of single use devices. Recently, 3D-printing technologies are under development for the generation of individual costumes made microfluidic devices in low numbers for reasonable prices. Here, we present an example for a complex droplet based screening network designed for bacterial screening purposes received by CD-production technologies. General principles of droplet based processing, fluidic devise units and peripheral analytical techniques will be introduced as well as details for the screening of soil bacteria will be given. As an outlook the future microfluidic techniques for monitoring or continuous sampling form large volume bioprocesses will be given
Improving the k-Nearest Neighbour Rule by an Evolutionary Voting Approach
This work presents an evolutionary approach to modify the
voting system of the k-Nearest Neighbours (kNN). The main novelty of
this article lies on the optimization process of voting regardless of the
distance of every neighbour. The calculated real-valued vector through
the evolutionary process can be seen as the relative contribution of every
neighbour to select the label of an unclassified example. We have tested
our approach on 30 datasets of the UCI repository and results have
been compared with those obtained from other 6 variants of the kNN
predictor, resulting in a realistic improvement statistically supported
Relationship between cortisol and physical performance in older persons
Objective: Hypercortisolism is associated with muscle weakness. This study examines the relationship between cortisol and physical performance in older persons. Design/patients: The study was conducted within the Longitudinal Aging Study Amsterdam (LASA), an ongoing cohort study in a population-based sample of healthy older persons in the Netherlands. Data from the second (1995/1996) and fourth (2001/2002) cycle were used pertaining to 1172 (65-88 years) and 884 (65-94 years) men and women, respectively. Measurements: Physical performance was measured by adding up scores on the chair stands, tandem stand and walk test (range 0-12). In the second cycle serum total and calculated free cortisol were assessed; in the fourth cycle evening salivary cortisol was assessed. Regression analysis (stratified for sex, adjusted for age, body mass index, alcohol use, physical activity and region) was performed to examine the cross-sectional relationship between cortisol and physical performance. Results: Women with higher calculated free cortisol scored less well on physical performance (b = -0.28 per SD higher cortisol, P = 0.016), which was mainly explained by poorer performance on the tandem stand (OR = 1.32 for a lower score per SD higher cortisol, P = 0.003). Men with higher salivary cortisol scored less well on physical performance (b = -0.90 in the highest vs. the lowest quartile, P = 0.008), which was mainly explained by poorer performance on the chair stands and walk test (OR = 1.88, P = 0.020 and OR = 1.81, P = 0.027, respectively, in the highest vs. the lowest quartile). Conclusion: Physical performance is negatively associated with high cortisol levels in older persons. © 2007 The Authors
Higher Reasoning with Level-2 Fuzzy Regions
Spatial data is quite often is prone to uncertainty and imprecision. For this purpose, fuzzy regions have been developed: they basically consist of a fuzzy set over a two dimensional domain, allowing for both fuzzy regions and fuzzy points to be modelled. The model is extended to a level-2 fuzzy region to overcome some limitations, but this has an impact on operations. In this contribution, we will look into the construction of and combination of existing data to yield level-2 fuzzy regions
An Interactive Approach Based on Alternative Achievement Scale and Alternative Comprehensive Scale for Multiple Attribute Decision Making under Linguistic Environment
The aim of this paper is to develop an interactive approach for multiple attribute decision making with incomplete
weight information under linguistic environment. Some of the concepts are defined, such as the distance between
two 2-tuple linguistic variables, the expectation level of alternative, the achievement scale, the alternative
comprehensive scale under linguistic environment. Based on these concepts, we establish some linear programming
models, through which the decision maker interacts with the analyst. Furthermore, we establish a practical
interactive approach for selecting the most desirable alternative(s). The interactive process can be realized by
giving and revising the achievement scale and comprehensive scale of alternatives till the achievement scale and
the comprehensive scale are achieved to the decision maker’s request. Finally, an illustrative example is also given.The author is very grateful to the associated editor and two anonymous referees for their insightful and constructive comments and suggestions that have led to an improved version of this paper. This work was partly supported by the National Natural Science Foundation of China (No. 90924027, No. 71101043), National Basic Research Program of China (973 Program, No. 2010C B951104), Key Program of National Social Science Foundation of China (No. 10AJY005), College Philosophy and Social Science Research Project of Jiangsu Province under Grant 2011SJD630007.Xu, Y.; Wang, H.; Palacios Marqués, D. (2013). An Interactive Approach Based on Alternative Achievement Scale and Alternative Comprehensive Scale for Multiple Attribute Decision Making under Linguistic Environment. International Journal of Computational Intelligence Systems. 6(1):87-95. https://doi.org/10.1080/18756891.2013.756226S87956
A História da Alimentação: balizas historiográficas
Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domÃnio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crÃtico da historiografia brasileira sobre o tema
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