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Providing appropriate methods to facilitate the analysis of time-oriented data is a key issue in many application domains. In this paper, we focus on the unique role of the parameter time in the context of visually driven data analysis. We will discuss three major aspects - visualization, analysis, and the user. It will be illustrated that it is necessary to consider the characteristics of time when generating visual representations. For that purpose we take a look at different types of time and present visual examples. Integrating visual and analytical methods has become an increasingly important issue. Therefore, we present our experiences in temporal data abstraction, principal component analysis, and clustering of larger volumes of time-oriented data. The third main aspect we discuss is supporting user-centered visual analysis. We describe event-based visualization as a promising means to adapt the visualization pipeline to needs and tasks of users.

Pantographic metamaterials: an example of mathematically driven design and of its technological challenges Abstract In this paper, we account for the research efforts that have been started, for some among us, already since 2003, and aimed to the design of a class of exotic architectured, optimized (meta) materials. At the first stage of these efforts, as it often happens, the research was based on the results of mathematical investiga-tions. The problem to be solved was stated as follows: determine the material (micro)structure governed by those equations that specify a desired behavior. Addressing this problem has led to the synthesis of second gradient materials. In the second stage, it has been necessary to develop numerical integration schemes andDipartimento di Ingegneria Strutturale e Geotecnica, Università degli Studi di Roma "La Sapienza.", Via Eudossiana 18, 00184 Rome, Italy E-mail: barchiesiemilio@gmail.com the corresponding codes for solving, in physically relevant cases, the chosen equations. Finally, it has been necessary to physically construct the theoretically synthesized microstructures. This has been possible by means of the recent developments in rapid prototyping technologies, which allow for the fabrication of some complex (micro)structures considered, up to now, to be simply some mathematical dreams. We show here a panorama of the results of our efforts (1) in designing pantographic metamaterials, (2) technology of rapid prototyping, and (3) in the mechanical testing of many real prototypes. Among the key findings that have been obtained, there are the following ones: pantographic metamaterials (1) undergo very large deformations while remaining in the elastic regime, (2) are very tough in resisting to damage phenomena, (3) exhibit robust macroscopic mechanical behavior with respect to minor changes in their microstructure and micromechanical properties, (4) have superior strength to weight ratio, (5) have predictable damage behavior, and (6) possess physical properties that are critically dictated by their geometry at the microlevel.

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Click here to access/download;Manuscript;Advances in Pantographic Structures.pdf Click here to view linked References Francesco dell'Isola et al.

In this paper, we present a representation for three‐dimensional geometric animation sequences. Different from standard key‐frame techniques, this approach is based on the determination of principal animation components and decouples the animation from the underlying geometry. The new representation supports progressive animation compression with spatial, as well as temporal, level‐of‐detail and high compression ratios. The distinction of animation and geometry allows for mapping animations onto other objects.

In this paper a novel ligand of the type [PNPNH] is presented for the application in a new homogeneous highly selective ethene trimerization system for the formation of 1‐hexene, which consists of the chromium source CrCl3(thf)3, the ligand Ph2PN(iPr)P(Ph)N(iPr)H (1), and Et3Al as an activator in toluene. The excellent characteristics of this new system, e.g. very high selectivity to C6 with highest purity of the C6 fraction (>99 % 1‐hexene), activity on a constant level on a long timescale, use of small amounts of Et3Al as a cheap activator, and only very low production of PE, make it to a hot candidate for industrial application. Its organometallic background gives an indication of the nature of the active catalyst species.

HPLC Separation of higher fullerenes was compared on two different stationary phases, and the preparative isolation of pure C76 is described. Higher‐fullerene derivatives 1 and 2 were prepared by Diels‐Alder reaction of C70 and C76 with an ortho‐quinodimethane intermediate generated in situ. Three out of four possible isomeric C70 monoadducts, i.e. 1a–c, and, for the first time, one isomeric C76 monoadduct, i.e. 2c, could be isolated in pure form and characterized by 1H‐NMR, 13C‐NMR, UV/VIS, and mass spectrometry. Five other C76 isomers i.e., 2a,b,d–f were obtained in partially separated product fractions. Coalescence temperatures and energy barriers were determined for the cyclohexene‐ring inversion in two of the isomeric C70 derivatives. The structure of the C70 adducts could be deduced unambiguously from symmetry considerations based on high‐ and low‐temperature 1H‐NMR spectroscopy. A simple model for the qualitative evaluation of the local curvature of fullerene surfaces is presented and used for the prediction of addition sites in higher fullerenes. These predictions are compared to the experimental results mentioned above as well as to predictions resulting from π‐bond‐order considerations and from calculated pyramidalization angles.