Relationships between hierarchical structure and properties in macromolecular systems

1987 ◽  
Vol 45 ◽  
pp. 440-443
Author(s):  
E. Baer
Keyword(s):  
Uniaxial Tension ◽  
Hierarchical Structure ◽  
Inorganic Material ◽  
Hierarchical Structures ◽  
Bone Collagen ◽  
Structure And Properties ◽  
Connective Tissues ◽  
Scale Level ◽  
Fibrous Protein ◽  
Macromolecular Systems

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.

Hierarchical Structure and Properties of Graphene Oxide Papers

2013 ◽  
Vol 80 (4) ◽  
Author(s):  
Charles D. Wood ◽  
Marc J. Palmeri ◽  
Karl W. Putz ◽  
Zhi An ◽  
SonBinh T. Nguyen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Structural Feature ◽  
Uniaxial Tension ◽  
Hierarchical Structure ◽  
Mechanical Response ◽  
Structure And Properties ◽  
Fracture Surfaces ◽  
High Stiffness ◽  
Significant Attention

The mechanical properties of graphene oxide papers have attracted significant attention in recent years due to their high stiffness and tough behavior. While the structural feature most commonly characterized is the nanosheet spacing, there is a hierarchical structure, which is likely responsible for the impressive mechanical properties. In this paper, we examine the structure of graphene oxide papers on several length scales using novel techniques to distinguish between lamellae and a newly defined feature, termed “super-lamellae.” The differentiation between these intermediate features provides context to the previously observed mechanical response and fracture surfaces of graphene oxide papers, particularly under uniaxial tension.

Hierarchical composition in complex object drawing

2019 ◽  
Author(s):  
Michiru Makuuchi
Keyword(s):  
Hierarchical Structure ◽  
Homo Sapiens ◽  
Hierarchical Structures ◽  
Target Object ◽  
Point Of View ◽  
Complex Object ◽  
Complex Objects ◽  
Cognitive Domains ◽  
Adult Participants ◽  
Symbolic Cognition

Symbolic behaviours such as language, music, drawing, dance, etc. are unique to humans and are found universally in every culture on earth1. These behaviours operate in different cognitive domains, but they are commonly characterised as linear sequences of symbols2,3. One of the most prominent features of language is hierarchical structure4, which is also found in music5,6 and mathematics7. Current research attempts to address whether hierarchical structure exists in drawing. When we draw complex objects, such as a face, we draw part by part in a hierarchical manner guided by visual semantic knowledge8. More specifically, we predicted how hierarchical structure emerges in drawing as follows. Although the drawing order of the constituent parts composing the target object is different amongst individuals, some parts will be drawn in succession consistently, thereby forming chunks. These chunks of parts would then be further integrated with other chunks into superordinate chunks, while showing differential affinity amongst chunks. The integration of chunks to an even higher chunk level repeats until finally reaching the full object. We analysed the order of drawing strokes of twenty-two complex objects by twenty-five young healthy adult participants with a cluster analysis9 and demonstrated reasonable hierarchical structures. The results suggest that drawing involves a linear production of symbols with a hierarchical structure. From an evolutionary point of view, we argue that ancient engravings and paintings manifest Homo sapiens’ capability for hierarchical symbolic cognition.

Perceiving Hierarchical Structures in Nonrepresentational Paintings

1998 ◽  
Vol 16 (1) ◽  
pp. 59-70 ◽  
Author(s):  
Tsion Avital ◽  
Gerald C. Cupchik
Keyword(s):  
Factor Analysis ◽  
Multidimensional Scaling ◽  
Hierarchical Structure ◽  
Hierarchical Structures ◽  
Exploratory Activity ◽  
Affective Responses ◽  
Hierarchical Complexity ◽  
The Hierarchical Structure ◽  
Relative Separation ◽  
Dimension 2

A series of four experiments were conducted to examine viewer perceptions of three sets of five nonrepresentational paintings. Increased complexity was embedded in the hierarchical structure of each set by carefully selecting colors and ordering them in each successive painting according to certain rules of transformation which created hierarchies. Experiment 1 supported the hypothesis that subjects would discern the hierarchical complexity underlying the sets of paintings. In Experiment 2 viewers rated the paintings on collative (complexity, disorder) and affective (pleasing, interesting, tension, and power) scales, and a factor analysis revealed that affective ratings were tied to complexity (Factor 1) but not to disorder (Factor 2). In Experiment 3, a measure of exploratory activity (free looking time) was correlated with complexity (Factor 1) but not with disorder (Factor 2). Multidimensional scaling was used in Experiment 4 to examine perceptions of the paintings seen in pairs. Dimension 1 contrasted Soft with Hard-Edged paintings, while Dimension 2 reflected the relative separation of figure from ground in these paintings. Together these results show that untrained viewers can discern hierarchical complexity in paintings and that this quality stimulates affective responses and exploratory activity.

scholarly journals Urchin-like CoO–C micro/nano hierarchical structures as high performance anode materials for Li-ion batteries

RSC Advances ◽  
2017 ◽  
Vol 7 (5) ◽  
pp. 2637-2643 ◽  
Author(s):  
Lili Liu ◽  
Lihui Mou ◽  
Jia Yu ◽  
Shimou Chen
Keyword(s):  
Hierarchical Structure ◽  
Anode Materials ◽  
High Performance ◽  
Hierarchical Structures ◽  
Li Ion Batteries ◽  
Carbon Coated ◽  
Li Ion ◽  
Li Storage

Urchin-like microspheres consisting of radial carbon-coated cobalt monoxide nanowires are designed, to fabricate a micro/nano hierarchical structure for efficient Li-storage.

Interactions Between Formal and Informal Organizational Networks

2009 ◽  
pp. 480-512 ◽  
Author(s):  
Marco Lamieri ◽  
Diana Mangalagiu
Keyword(s):  
Social Network ◽  
Problem Solving ◽  
Hierarchical Structure ◽  
Stable Process ◽  
Hierarchical Structures ◽  
Review Of The Literature ◽  
Market Conditions ◽  
Variable Environment ◽  
The Social ◽  
Definition Of

In this chapter we present a model of organization aimed to understand the effect of formal and informal structures on the organization’s performance. The model considers the interplay between the formal hierarchical structure and the social network connecting informally the agents emerging while the organization performs a task-set. The social network creation and evolution is endogenous, as it doesn’t include any function supposed to optimize performance. After a review of the literature, we propose a definition of performance based on the efficiency in allocating the task of a simulated organization that can be considered as a network-based problem-solving system. We analyze how the emergence of a stable process in decomposing tasks under different market conditions can alleviate the rigidity and the inefficiencies of a hierarchical structure and we compare the performance of different hierarchical structures under variable environment conditions.

scholarly journals Accurate measurement of specific tensile strength of carbon nanotube fibers with hierarchical structures by vibroscopic method

RSC Advances ◽  
2017 ◽  
Vol 7 (14) ◽  
pp. 8575-8580 ◽  
Author(s):  
Junbeom Park ◽  
Sung-Hyun Lee ◽  
Jaegeun Lee ◽  
Dong-Myeong Lee ◽  
Hayoung Yu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Carbon Nanotube ◽  
Hierarchical Structure ◽  
Linear Density ◽  
Hierarchical Structures ◽  
Specific Strength ◽  
Real Value ◽  
Carbon Nanotube Fibers

Since carbon nanotube (CNT) fibers have a hierarchical structure, the specific strength of CNT fibers can be estimated to be much higher than its real value when the linear density of the fiber is measured using the vibroscopic method.

Hierarchical Parallel Processes of Genetic Algorithms for Design Optimization of Large-Scale Products

2000 ◽  
Author(s):  
Masataka Yoshimura ◽  
Kazuhiro Izui
Keyword(s):  
Genetic Algorithms ◽  
Hierarchical Structure ◽  
Large Scale ◽  
Hierarchical Structures ◽  
Pareto Optimum ◽  
Local Optima ◽  
Large Scale Systems ◽  
Parallel Processes ◽  
The Hierarchical Structure ◽  
Optimization Search

Abstract A large-scale machine system often has a general hierarchical structure. For hierarchical structures, optimization is difficult because many local optima almost always arise, however genetic algorithms that have a hierarchical genotype can be applied to treat such problems directly. Relations between the structural components are analyzed and this information is used to partition the hierarchical structure. Partitioning large-scale problems into sub-problems that can be solved using parallel processed GAs increases the efficiency of the optimization search. The optimization of large-scale systems then becomes possible due to information sharing of Pareto optimum solutions for the sub-problems.

Ranking the Difficulty Level of the Knowledge Units Based on Learning Dependency

2012 ◽  
Vol 10 (1) ◽  
pp. 31-43
Author(s):  
Jun Liu ◽  
Sha Sha ◽  
Qinghua Zheng ◽  
Wei Zhang
Keyword(s):  
Hierarchical Structure ◽  
Plane Geometry ◽  
Learning Activities ◽  
Difficulty Level ◽  
Knowledge Map ◽  
Structure And Properties ◽  
Factors Influencing ◽  
The Hierarchical Structure ◽  
Level Of Knowledge

Assigning difficulty level indicators to the knowledge units helps the learners plan their learning activities more efficiently. This paper focuses on how to use the topology of a knowledge map to compute and rank the difficulty levels of knowledge units. Firstly, the authors present the hierarchical structure and properties of the knowledge map. Then they propose three hypotheses of factors influencing difficulty based on the correlation between the difficulty level of knowledge units and the learning dependency. Finally, the authors provide algorithms for ranking the knowledge units with objective and subjective difficulty scores. The experiment on the knowledge map of the “plane geometry” course shows that our algorithm can precisely calculate the difficulty level of knowledge units.

Layer like porous materials with hierarchical structure

2016 ◽  
Vol 45 (12) ◽  
pp. 3400-3438 ◽  
Author(s):  
Wieslaw J. Roth ◽  
Barbara Gil ◽  
Wacław Makowski ◽  
Bartosz Marszalek ◽  
Pavla Eliášová
Keyword(s):  
Porous Materials ◽  
Hierarchical Structure ◽  
Hierarchical Structures ◽  
Extended Sheets

Various hierarchical structures have been produced spontaneously or by modification from layered solids consisting of extended sheets with thickness not greater than a few nanometers.

Graphene foam with hierarchical structures for the removal of organic pollutants from water

RSC Advances ◽  
2016 ◽  
Vol 6 (6) ◽  
pp. 4889-4898 ◽  
Author(s):  
Sudong Yang ◽  
Lin Chen ◽  
Lei Mu ◽  
Bin Hao ◽  
Junteng Chen ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Organic Pollutants ◽  
Hierarchical Structure ◽  
Hierarchical Structures ◽  
High Porosity ◽  
Water Separation ◽  
Graphene Foam ◽  
Excellent Thermal Stability ◽  
Oil Water Separation ◽  
Oil Water

Graphene foam with hierarchical structure was prepared. The developed material exhibited high porosity, hydrophobicity, excellent thermal stability, and can be for oil–water separation.

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