Large Hierarchical Structure Research Articles

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The article represents the author's reflection on the key features of the philosophical generation that was formed in the Russian-speaking space in the 10s of the 20th century. The author believes that a relevant theoretical lens for considering the specifics that distinguish young people who began their journey in philosophy during these years could be an appeal to the sociological typology of generations. According to the authoritative sociologist Vadim Radaev, the designated philosophical generation belongs to the “millennials.” The key characteristics that distinguish these young people include isolation, passion for gadgets and everyday digitalization, lack of desire to build a career, and inability to integrate into large hierarchical structures. Based on his personal experience, presented in the form of brief notes on key topics shaping the intellectual generation – magazines, people, books, places – the author invites the reader to consider some circumstances of his personal intellectual biography that could serve as evidence confirming the hypothesis. Without hoping to be able to “capture” the essence of his generation, the author hopes that his memories may be useful for subsequent comparative analysis.

A hybrid seesaw model and hierarchical neutrino flavor structures based on A4 symmetry

Abstract We propose a hybrid seesaw model based on $A_{4}$ flavor symmetry, which generates a large hierarchical flavor structure. In our model, tree-level and one-loop seesaw mechanisms predict different flavor structures in the neutrino mass matrix and generate a notable hierarchy among them. We find that such a hierarchical structure gives a large effective neutrino mass that can be accessible by next-generation neutrinoless double beta decay experiments. Majorana phases can also be predictable. The $A_{4}$ flavor symmetry in the model is spontaneously broken to the $Z_{2}$ symmetry, leading to a dark matter candidate that is assumed to be a neutral scalar field. The favored mass region of the dark matter is obtained by numerical computations of the relic abundance and the cross section of the nucleon. We also investigate the predictions of several hierarchical flavor structures based on $A_{4}$ symmetry for the effective neutrino mass and the Majorana phases, and find characteristic features depending on the hierarchical structures.

Depicting More Information in Enriched Squarified Treemaps with Layered Glyphs

The Treemap is one of the most relevant information visualization (InfoVis) techniques to support the analysis of large hierarchical data structures or data clusters. Despite that, Treemap still presents some challenges for data representation, such as the few options for visual data mappings and the inability to represent zero and negative values. Additionally, visualizing high dimensional data requires many hierarchies, which can impair data visualization. Thus, this paper proposes to add layered glyphs to Treemap’s items to mitigate these issues. Layered glyphs are composed of N partially visible layers, and each layer maps one data dimension to a visual variable. Since the area of the upper layers is always smaller than the bottom ones, the layers can be stacked to compose a multidimensional glyph. To validate this proposal, we conducted a user study to compare three scenarios of visual data mappings for Treemaps: only Glyphs (G), Glyphs and Hierarchy (GH), and only Hierarchy (H). Thirty-six volunteers with a background in InfoVis techniques, organized into three groups of twelve (one group per scenario), performed 8 InfoVis tasks using only one of the proposed scenarios. The results point that scenario GH presented the best accuracy while having a task-solving time similar to scenario H, which suggests that representing more data in Treemaps with layered glyphs enriched the Treemap visualization capabilities without impairing the data readability.

Poly(4‐vinyl imidazole): A pH‐Responsive Trigger for Hierarchical Self‐Assembly of Multicompartment Micelles Based upon Triblock Terpolymers

AbstractPoly(vinyl pyridine) has widely been used as a pH‐responsive polymer to trigger changes in self‐assembly of block copolymer micelles. However, the polymer is known to display toxic features, which limits its ultimate applicability for biological applications. Here, poly(4‐vinyl imidazole) (P4VIm), a much more biocompatible polymer, is used as a pH‐responsive block to modulate the self‐assembly of ABC triblock terpolymers. In this article, the synthesis of the poly(1‐acryloyl fructopyranose)‐block‐ poly(n‐butyl acrylate)‐block‐ poly(4‐vinyl imidazole) (PFruA52‐b‐PBuA300‐b‐P4VIm250) triblock terpolymers is first discussed by sequential reversible addition fragmentation chain transfer (RAFT) polymerization. Subsequently, the structure formation of the triblock terpolymer is elucidated by step‐wise solvent exchange. The polymer readily dissolves in methanol, but self‐assembles into micelles with PBuA cores and mixed shell in methanol–water mixtures. Solvent exchange against buffer solutions of pH 6–6.5 leads to collapse of P4VIm due to deprotonation and induces self‐assembly into caterpillar‐like non‐spherical nanoparticles, most likely via the formation of intermediate Janus particles. The rearrangement into larger hierarchical structure, as seen by small angle X‐ray scattering (SAXS), is found to process within several hours. The article is concluded by demonstrating lower cytotoxicity values for the present polymer in comparison to a structurally analogous triblock terpolymer based on poly(vinyl pyridine).

OntoPlot: A Novel Visualisation for Non-hierarchical Associations in Large Ontologies

Ontologies are formal representations of concepts and complex relationships among them. They have been widely used to capture comprehensive domain knowledge in areas such as biology and medicine, where large and complex ontologies can contain hundreds of thousands of concepts. Especially due to the large size of ontologies, visualisation is useful for authoring, exploring and understanding their underlying data. Existing ontology visualisation tools generally focus on the hierarchical structure, giving much less emphasis to non-hierarchical associations. In this paper we present OntoPlot, a novel visualisation specifically designed to facilitate the exploration of all concept associations whilst still showing an ontology's large hierarchical structure. This hybrid visualisation combines icicle plots, visual compression techniques and interactivity, improving space-efficiency and reducing visual structural complexity. We conducted a user study with domain experts to evaluate the usability of OntoPlot, comparing it with the de facto ontology editor Protégé. The results confirm that OntoPlot attains our design goals for association-related tasks and is strongly favoured by domain experts.

Enabling effective tree exploration using visual cues

This article presents a new interactive visualization for exploring large hierarchical structures by providing visual cues on a node link tree visualization. Our technique provides topological previews of hidden substructures with three types of visual cues including simple cues, tree cues and treemap cues. We demonstrate the visual cues on Degree-of-Interest Tree (DOITree) due to its familiar mapping, its capability of providing multiple focused nodes, and its dynamic rescaling of substructures to fit the available space. We conducted a usability study with 28 participants that measured completion time and accuracy across five different topology search tasks. The simple cues had the fastest completion time across three of the node identification tasks. The treemap cues had the highest rate of correct answers on four of the five tasks, although only reaching statistical significance for two of these. As predicted, user ratings demonstrated a preference for the easy to understand tree cues followed by the simple cue, despite this not consistently reflected in performance results.

Radiation Pressure Induced Hierarchical Structure of Liquid Crystalline Inorganic Nanosheets

Although hierarchical assemblies of colloidal particles add novel structure-based functions to systems, few local and on-demand colloidal structures have been developed. We have combined the colloidal liquid crystallinity of two-dimensional inorganic particles and laser radiation pressure to obtain a large hierarchical and local structure in a colloidal system. The scattering force of the laser beam converted the parallel nanosheet alignment to the direction of the incident laser beam. At the focal point, the nanosheet orientation depends on the electric field of the polarized laser beam. In contrast, a giant tree-ring-like nanosheet texture of more than 100 μm, and which is independent of the polarization direction, was organized at the periphery of the focal point. This organization resulted from a cooperative effect between the liquid-crystalline nanosheets, which indicates an effectiveness of optical manipulation to construct hierarchical colloidal structures with the aid of interparticle interactions.

A Study on the Effectiveness of Tree-Maps as Tree Visualization Techniques

Tree Structure visualization techniques are one of the important techniques to support the analysis of large hierarchical structure data. They are typically used as tree structure node-link diagram. However, it is difficult to visualize the content of directories when there are too many child nodes. In this paper, a study on the effectiveness of the tree-maps as tree structure visualization will be presented. Tree-maps are always considered as one of the interesting topic of research in HCI. Therefore, in this paper we will discuss about applying various types of Tree-maps as one of the visualization techniques. First, we will look into current problem faced by Tree structured node-link diagram. We will also look into four main types of tree-maps such as original tree-maps, Circular Tree-maps, Cushion Tree-maps and 3D Tree-maps. Finally, the effectiveness of these tree-maps to visualize the hierarchy of the directory will be investigated by conducting a simple user experiments.

Divide and Conquer treemaps: Visualizing large trees with various shapes

Most existing treemaps achieve the space utilization of a single geometrical area, mostly rectangle. Limiting visualization to rectangles could block the human capability on graph recognition, including orientation, shape and differentiation etc. To relax rectangular constraint, we propose a flexible enclosure approach with three algorithms. It partitions large hierarchical structures within a confined display area with different shapes for real-time applications. Our approach is based on the combination of Divide-and-Conquer method and the treemap paradigm. The partitioning algorithms generate three types of layouts with polygonal, angular and rectangular titling, which are flexible to be used separately or combined. We present technical details including the visualization results in the experiments and in the cases studies with real data sets. We evaluated the visualization based on graph drawing aesthetics and optimization criteria. Our usability study shows that (1) treemaps with layout variability support utilization of human capability in graph perception and (2) treemaps adopted in different shaped containers could have a positive impact on user satisfaction and awareness during visual data exploration.

D-brane instanton inducedμterms and their hierarchical structure

We study the mu-term matrix of Higgs pairs induced by the D-brane instanton effects in intersecting D6-brane models compactified on T6. It is found that the mu-term matrix has a certain permutation symmetry and its eigenvalues have large hierarchical structure without fine tuning.

PF BL-15A for semi-microbeam XAFS/XRF and high-brilliance SAXS/GI-SAXS

New beamline, BL-15A, was completed at the BL-15 section of the PF-ring in 2014. This new beamline has a short gap undulator which produces high brilliance X-rays ranging from 2.1 keV to 15 keV. The beamline will be dedicated to both activities, XAFS/XRF/XRD studies using semi-micro focus beams (A1 station) and SAXS experiments using collimated softer and hard X-rays (A2 station). In the XAFS/XRF studies, the semi-micro beam available in a wide range of photon energies allows analyzing the local structures of the elements and valence on inhomogeneous samples in the fields of environmental science and new energy source science. The softer X-rays up to 2.1 keV will provide access to absorption edges of phosphor and sulfur, which are very important targets for those fields. The SAXS scientific programs include structural studies of functional membranes, time-resolved X-ray scattering and large hierarchical structure analysis. All of these three programs require a high-brilliance light source. In particular, grazing incidence SAXS (GI-SAXS) using vertically small-size softer beam ranging between 2.1-3.0 keV will help to control the depth of the membrane structure analysis and reduce the roughness defects of an imperfect membrane. The combination of XAFS/XRF and SAXS experiments gives wide structural information from fine atomic structure to low and medium resolution. It can be beneficial to build these instruments as two stations on the same beamline. BL-15A is oriented toward joint advanced studies by the two techniques. Old BL-15 beamlines were scrapped and new construction work started in 2013. The construction was completed in the summer shutdown of 2013 and the first beams was delivered on Oct 17, 2013. We are pursuing the beamline commissioning and the A1 and A2 stations will be opened to users in May, 2014. Here, the beamline design and performance, and the preliminary results will be reported.

HIERARCHICAL FRAGMENTATION OF THE ORION MOLECULAR FILAMENTS

We present a high angular resolution map of 850 um continuum emission of the Orion Molecular Cloud-3 (OMC 3) obtained with the Submillimeter Array (SMA); the map is a mosaic of 85 pointings covering an approximate area of 6'.5 x 2'.0 (0.88 x 0.27 pc). We detect 12 spatially resolved continuum sources, each with an H_2 mass between 0.3-5.7 Mo and a projected source size between 1400-8200 AU. All the detected sources are on the filamentary main ridge n_H2>10^6 cm^-3), and analysis based on the Jeans theorem suggests that they are most likely gravitationally unstable. Comparison of multi-wavelength data sets indicates that of the continuum sources, 6/12 (50 %) are associated with molecular outflows, 8/12 (67 %) are associated with infrared sources, and 3/12 (25 %) are associated with ionized jets. The evolutionary status of these sources ranges from prestellar cores to protostar phase, confirming that OMC-3 is an active region with ongoing embedded star-formation. We detect quasi-periodical separations between the OMC-3 sources of ~17"/0.035 pc. This spatial distribution is part of a large hierarchical structure, that also includes fragmentation scales of GMC (~35 pc), large-scale clumps (~1.3 pc), and small-scale clumps (~0.3 pc), suggesting that hierarchical fragmentation operates within the Orion A molecular cloud. The fragmentation spacings are roughly consistent with the thermal fragmentation length in large-scale clumps, while for small-scale cores it is smaller than the local fragmentation length. These smaller spacings observed with the SMA can be explained by either a helical magnetic field, cloud rotation, or/and global filament collapse. Finally, possible evidence for sequential fragmentation is suggested in the northern part of the OMC-3 filament.

Hyperbolic Wheel: A Novel Hyperbolic Space Graph Viewer for Hierarchical Information Content

Tree and graph structures have been widely used to present hierarchical and linked data. Hyperbolic trees are special types of graphs composed of nodes (points or vertices) and edges (connecting lines), which are visualized on a non-Euclidean space. In traditional Euclidean space graph visualization, distances between nodes are measured by straight lines. Displays of large graphs in Euclidean spaces may not utilize efficiently the available space and may impose limitations on the number of graph nodes. The special hyperbolic space rendering of tree-graphs enables adaptive and efficient use of the available space and facilitates the display of large hierarchical structures. In this paper we report on a newly developed advanced hyperbolic graph viewer, Hyperbolic Wheel, which enables the navigation, traversal, discovery and interactive manipulation of information stored in large hierarchical structures. Examples of such structures include personnel records, disc directory structures, ontological constructs, web-pages and other nested partitions. The Hyperbolic Wheel framework provides an intuitive and dynamic graphical interface to explore and retrieve information about individual nodes (data objects) and their relationships (data associations). The Hyperbolic Wheel is freely available online for educational and research purposes.

Herringbone and Helical Self-Assembly of π-Conjugated Molecules in the Solid State through CH/π Hydrogen Bonds

Self-organization of organic molecules through weak noncovalent forces such as CH/π interactions and creation of large hierarchical supramolecular structures in the solid state are at the very early stage of research. The present study reports direct evidence for CH/π interaction driven hierarchical self-assembly in π-conjugated molecules based on custom-designed oligophenylenevinylenes (OPVs) whose structures differ only in the number of carbon atoms in the tails. Single-crystal X-ray structures were resolved for these OPV synthons and the existence of long-range multiple-arm CH/π interactions was revealed in the crystal lattices. Alignment of these π-conjugated OPVs in the solid state was found to be crucial in producing either right-handed herringbone packing in the crystal or left-handed helices in the liquid-crystalline mesophase. Pitch- and roll-angle displacements of OPV chromophores were determined to trace the effect of the molecular inclination on the ordering of hierarchical structures. Furthermore, circular dichroism studies on the OPVs were carried out in the aligned helical structures to prove the existence of molecular self-assembly. Thus, the present strategy opens up new approaches in supramolecular chemistry based on weak CH/π hydrogen bonding, more specifically in π-conjugated materials.

A New State of MIIND

Event Abstract Back to Event A New State of MIIND Dave Harrison1* and Marc De Kamps1 1 University of Leeds, United Kingdom Multiple Interacting Instantiations of Neuronal Dynamics (MIIND) [1] is a software suite for the simulation of neuronal circuits and large-scale networks. MIIND models at the level of the population. It is very easy to model circuits of populations and visualize the dynamics. Whole circuits can now be embedded in large hierarchical structures so that networks of circuits with considerable spatial complexity can be created. The activation of the networks can be visualized in 2D and 3D. Although MIIND is a C++ framework, with the associated performance benefits, much of its functionality can be accessed in Python. Uniquely, MIIND offers the possibility to simulate neural populations with population density techniques. Conventional population simulation techniques require a large number of neurons to be simulated and then to calculate relevant population statistics by spike counting and averaging. With population density techniques these averages are simulated directly, bypassing the simulation of individual neurons. This leads to remarkably efficient simulations. MIIND is the only publicly available repository of population density algorithms. Recently, we have managed to include networks of leaky-integrate-and-fire neurons with balanced excitation-inhibition. In the diffusion approximation this entails the solution of Fokker-Planck equations, but importantly, our algorithms are also applicable outside of the diffusion regime. At present MIIND is a powerful tool for the simulation of large networks of spiking neuron populations and the presentation of their results. MIIND is an open source framework for computational and cognitive neuroscience, which exposes application programming interfaces for the creation of neural models of cognition through design patterns. This allows rapid application development through reuse of contributed components to create complex neural models. We will demonstrate a number of applications developed with MIIND to show coupled systems of Wilson-Cowan and Fokker-Planck equations. The demonstrations are shown from within a graphical interface to a dynamical model of visual attention. The software allows the time-course of neural activity to be visualised as a complete model, as cortical circuits, and as individual neurons or neural populations.

A Multilevel Navigation Aid for Hierarchical Structures: An Innovation Case Study and Empirical Evaluation

The paper presents a novel user interface (Gardner, et al., 2005) designed by LexisNexis® to assist researchers navigating large hierarchical structures. This navigation tool allows users of large hierarchies (e.g., tables of contents or file directories) to select an item (node) in the structure and expand (or collapse) it across multiple levels with a single selection. User evaluation was conducted with no participants training or prior use, finding the interface effective for complex navigation. Nearly a third (of 18) immediately displayed and selected hi***erarchy levels with no hesitation, even when expanding an entire table of contents section to its lowest level. While these participants were those most experienced with large documents, several less-experienced participants used the interface easily once prompted. While the remainder experienced some difficulties with initial interaction, these were related to context, domain experience, and prior habit rather than tool usability.

Rendering hierarchical data

Why is my hard disk full? A question no doubt familiar to many readers, and one that has inspired our research for several years. Our goal is to provide more insight into large, hierarchical data sets, commonly known as trees. Hierarchical data sets can be found everywhere. A large number of items, such as files, products, employees, and stocks, can be handled and managed much more efficiently when they are grouped into larger entities. Recursive application of this approach results in a tree structure. A hierarchical file system is a prime example: The user can organize his disk, and only has to deal with a limited set of files while fulfilling a task. But the PC disk of an average user often contains dozens of gigabytes of data, distributed over hundreds of thousands of files. In this case it becomes difficult to maintain an overview, and to determine what is cluttering the disk. Often no single, simple answer exists. Perhaps another user of the PC has installed some large programs, or has failed to cleanup after finishing a task in his or her relief at meeting a deadline. Perhaps multiple copies of the same multimedia file are stored on the disk. How can we find large files and directories and identify patterns and structures easily in such large hierarchical data structures? Automatic methods, such as searching for the largest files, fall short, and standard file browsers, using indented lists, have not been developed with this problem in mind. We believe the best way to answer our question is to exploit the unique capabilities of the human visual system, tuned and optimized in the course of millions of years of evolution to extract information from images [9]. In other words, let us try to make synthetic images, using a wide variety of visual cues to transfer information as efficiently and effectively as possible.

Synthesis and electrochemical properties of mesostructured 12-phosphotungstic acid thin films with hierarchical structures by triblock copolymer templating

ABSTRACTHexagonally mesostructured 12-phosphotungstic acid (PWA) thin films with both large pore size and hierarchical structures have been successfully prepared by using triblock copolymer templates for the first time. The films is composed by three kind of structures; PWA Keggin anion, monoclinic crystal structure consisting of PWA Keggin anion and organic part (hydrophilic component) of block copolymers, and the hexagonal mesostructure of self-arrayed PWA and block copolymers. The calcined PWA films show better electrochemical properties such as a faster faradic processes and larger specific capacity than normal P WA clusters.