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31.
Precise microphotometric assessment of intermediate cells from patients with normal cervical cytology and from patients with dysplasia or carcinoma in situ shows the existence of small but consistent differences. Marker features for the presence of premalignant and malignant disease can be extracted from the cell images of "normal"-appearing intermediate cells. The marker features and their diagnostic classification potential are described.  相似文献   
32.
The ‘will, skill, tool’ model is a well-established theoretical framework that elucidates the conditions under which teachers are most likely to employ information and communication technologies (ICT) in the classroom. Past studies have shown that these three factors explain a very high degree of variance in the frequency of classroom ICT use. The present study replicates past findings using a different set of measures and hones in on possible subfactors. Furthermore, the study examines teacher affiliation for constructivist-style teaching, which is often considered to facilitate the pedagogical use of digital media. The study’s survey of 357 Swiss secondary school teachers reveals significant positive correlations between will, skill, and tool variables and the combined frequency and diversity of technology use in teaching. A multiple linear regression model was used to identify relevant subfactors. Five factors account for a total of 60% of the explained variance in the intensity of classroom ICT use. Computer and Internet applications are more often used by teachers in the classroom when: (1) teachers consider themselves to be more competent in using ICT for teaching; (2) more computers are readily available; (3) the teacher is a form teacher and responsible for the class; (4) the teacher is more convinced that computers improve student learning; and (5) the teacher more often employs constructivist forms of teaching and learning. The impact of constructivist teaching was small, however.  相似文献   
33.
Two dimensional simulations of non-cohesive granular matter in a biaxial shear tester are discussed. The effect of particle elasticity on the mechanical behavior is investigated using two complementary distinct element methods (DEM): Soft particle molecular dynamics simulations (Particle Flow Code, PFC) for elastic particles and contact dynamics simulations (CD) for the limit of perfectly rigid particles. As soon as the system dilates to form shear bands, it relaxes the elastic strains so that one finds the same stresses for rigid respectively elastic particles in steady state flow. The principal stresses in steady state flow are determined. They are proportional to each other, giving rise to an effective macroscopic friction coefficient which is about 10% smaller than the microscopic friction coefficient between the grains.  相似文献   
34.
Software and Systems Modeling - The notation of a modeling language is of paramount importance for its efficient use and the correct comprehension of created models. A graphical notation,...  相似文献   
35.
Private transport accounts for a large amount of total CO2 emissions, thus significantly contributing to global warming. Tools that actively support people in engaging in a more sustainable life-style without restricting their mobility are urgently needed. How can location-aware information and communication technology (ICT) enable novel interactive and participatory approaches that help people in becoming more sustainable? In this survey paper, we discuss the different aspects of this challenge from a technological and cognitive engineering perspective, based on an overview of the main information processes that may influence mobility behavior. We review the state-of-the-art of research with respect to various ways of influencing mobility behavior (e.g., through providing real-time, user-specific, and location-based feedback) and suggest a corresponding research agenda. We conclude that future research has to focus on reflecting individual goals in providing personal feedback and recommendations that take into account different motivational stages. In addition, a long-term and large-scale empirical evaluation of such tools is necessary.  相似文献   
36.
Development of modern Software Defined Radio (SDR) based communication systems can be accelerated significantly by the use of processing frameworks. The evolution of SDR and the involved departure from digital representations of classical radio architecture towards more abstract software systems raises new requirements of increased flexibility and versatility. The proposed Data Flow Control for C++ (DFC++) processing framework concept addresses those requirements by employing modern programming techniques and flow control mechanisms to allow for variable data rates, dynamic paths, and flexible component designs. Another important trend is the integration of various embedded platforms in the software radio domain. The rapidly increasing performance and efficiency of embedded processors enables the deployment of SDR systems in more space and power constrained environments. Therefore covering a heterogeneous hardware selection becomes increasingly important for processing frameworks. By relying exclusively on C++ and minimizing external dependencies, DFC++ is specifically aiming for excellent portability and adaptability to support a wide range of current and future software radio projects while maintaining high performance and ease of use. This paper introduces the key aspects of the DFC++ concept and implementation with focus on the reference pointer based data transport mechanisms responsible for the propagation of user data between different processing components.  相似文献   
37.
In this paper, we analyse a systematically designed and easily tunable backstepping-based boundary control concept for a gantry crane with heavy chain and payload. The corresponding closed-loop system is formulated as an abstract evolution equation in an appropriate Hilbert space. Non-restrictive conditions for the controller coefficients are derived, under which the solutions are described by a C0-semi-group of contractions, and are asymptotically stable. Moreover, by applying Huang's theorem we can finally even show that under these conditions the controller renders the closed-loop system exponentially stable.  相似文献   
38.
39.
In this paper we analyze the effect of including price competition into a classical (market entrant’s) competitive location problem. The multinomial logit approach is applied to model the decision process of utility maximizing customers. We provide complexity results and show that, given the locations of all facilities, a fixed-point iteration approach that has previously been introduced in the literature can be adapted to reliably and quickly determine local price equilibria. We present examples of problem instances that demonstrate the potential non-existence of price equilibria and the case of multiple local equilibria in prices. Furthermore, we show that different price sensitivity levels of customers may actually affect optimal locations of facilities, and we provide first insights into the performance of heuristic algorithms for the location problem.  相似文献   
40.
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