scholarly journals Design and Dynamic Equivalent Modeling of Double-Layer Hoop Deployable Antenna

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Hongwei Guo ◽  
Chuang Shi ◽  
Meng Li ◽  
Zongquan Deng ◽  
Rongqiang Liu
Keyword(s):  
Double Layer ◽  
Strain Energy ◽  
Structural Characteristics ◽  
Equivalent Model ◽  
Material Parameters ◽  
Modal Test ◽  
Element Simulation ◽  
Energy Equivalence ◽  
Relationship Of ◽  
The Relationship

This study proposes deployable units driven by elastic hinges and a double-layer hoop deployable antenna composed of these units. A rational modeling method based on the energy equivalence principle is presented to develop an equivalent model of the double-layer hoop antenna in accordance with the structural characteristics of the antenna. The equivalent beam models of the rods with elastic hinges are proposed. The relationship of geometrical and material parameters is established considering the strain energy and the kinetic energy of the periodic unit, which are the same as those of the equivalent beam in the same displacement field. The equivalent model of the antenna is obtained by assembling several equivalent beam models in the circumferential direction. The precision of the equivalent model of the antenna is acceptable as found by comparing the modal analysis results obtained through equivalent model calculation, finite element simulation, and modal test.

Study on Wood Carbon Sequestration Based on Micro-Characteristics of Wood

2010 ◽  
Vol 113-116 ◽  
pp. 1693-1696
Author(s):  
Ming Hui Guo ◽  
Xin Guan ◽  
Li Zhu ◽  
Jian Li
Keyword(s):  
Carbon Sequestration ◽  
Forest Ecosystems ◽  
Structural Characteristics ◽  
Structural Features ◽  
Carbon Stocks ◽  
Xylem Parenchyma ◽  
Micro Level ◽  
Relationship Of ◽  
The Relationship

Trees are complicated and important organisms in forest ecosystem. They are both carbon stocks and carbon source. In order to give full play to the role of wood carbon sequestration, this paper discussed the relationship of wood structural features and wood carbon sequestration at micro-level. It shows that wood carbon sequestration can be synthetically reflected by vessel, tracheid/xylon, wood rays, intercellular canal, xylem parenchyma and so on. The rate of cell wall and wood carbon sequestration is the relationship of direct proportional function. Micro-structural characteristics of wood can reflect wood carbon sequestration of forest ecosystems, as well as have a practical guide to enhance carbon storage of wood.

scholarly journals Species Abundance and Body Size Relationship of Bird Assemblages at Selected Sites in Western Sarawak

2020 ◽  
Vol 3 (2) ◽  
pp. a18-25
Author(s):  
AHMAD FITRI AZIZ ◽  
CHARLIE JUSTIN MERGIE LAMAN
Keyword(s):  
Body Size ◽  
Regression Line ◽  
Species Abundance ◽  
General Rule ◽  
Bird Assemblages ◽  
Energy Equivalence ◽  
Average Body Mass ◽  
Relationship Of ◽  
The Relationship ◽  
Combined Data

The Energy Equivalence Rule (EER) is an unresolved issue in ecology. This rule states that the amount of energy used for each species in a population is independent of its body size. A study on the relationship between abundance and body size of bird assemblages was conducted in Western Sarawak. Abundance data of bird assemblages from seven selected sites in Western Sarawak were used to produce a regression line of log absolute species abundance versus log average body mass. Data from all selected sites were combined to represent bird assemblages in Western Sarawak and the slope produced was -0.216. The slopes obtained for each site were 0.808, -0.080, -0.258, -0.067, -0.161, -0.072 and -0.237, respectively. Statistical analysis shows that the slope of combined data did not differ significantly from -0.75, as expected under the EER. Thus, this study shows that the EER can be applied as a general rule of community structure of bird assemblages in Western Sarawak.

scholarly journals A Concise Review on the Molecular Structure and Function Relationship of β-Glucan

2019 ◽  
Vol 20 (16) ◽  
pp. 4032 ◽  
Author(s):  
Bin Du ◽  
Maninder Meenu ◽  
Hongzhi Liu ◽  
Baojun Xu
Keyword(s):  
Molecular Structure ◽  
Functional Food ◽  
Structural Characteristics ◽  
Textural Properties ◽  
High Viscosity ◽  
Biological Properties ◽  
Food Ingredient ◽  
And Function ◽  
Relationship Of ◽  
The Relationship

β-glucan is a non-starch soluble polysaccharide widely present in yeast, mushrooms, bacteria, algae, barley, and oat. β-Glucan is regarded as a functional food ingredient due to its various health benefits. The high molecular weight (Mw) and high viscosity of β-glucan are responsible for its hypocholesterolemic and hypoglycemic properties. Thus, β-glucan is also used in the food industry for the production of functional food products. The inherent gel-forming property and high viscosity of β-glucan lead to the production of low-fat foods with improved textural properties. Various studies have reported the relationship between the molecular structure of β-glucan and its functionality. The structural characteristics of β-glucan, including specific glycosidic linkages, monosaccharide compositions, Mw, and chain conformation, were reported to affect its physiochemical and biological properties. Researchers have also reported some chemical, physical, and enzymatic treatments can successfully alter the molecular structure and functionalities of β-glucan. This review article attempts to review the available literature on the relationship of the molecular structure of β-glucan with its functionalities, and future perspectives in this area.

Structural Characterization of Micron-scaled Reticulated Copper Foams

2011 ◽  
Vol 1304 ◽  
Author(s):  
Stephanie J Lin ◽  
Jason H. Nadler
Keyword(s):  
Image Analysis ◽  
Structural Characteristics ◽  
Porous Network ◽  
Unique Challenge ◽  
Copper Foam ◽  
Fluid Permeability ◽  
Capillary Fluid ◽  
Relationship Of ◽  
The Relationship

AbstractThe development of a multifunctional, micron-scaled, reticulated copper foam that reliably exhibits high intrinsic thermal conductivity, efficient capillary fluid and evaporative transport over a wide area presents a unique challenge. In this work, the relationship of critical foam processing variables such as sintering temperature and template size on the pore size distribution and pore neck/body ratio is investigated using image analysis. The resulting fluid permeability values of these foams are estimated by using the Kozeny Carman equation and the porosity, surface area per unit area and tortuosity obtained through image analysis. Estimating the fluid permeability of these foams is useful for predicting the mass and heat transfer within the porous network, and provides a metric for optimizing the foam’s structural characteristics for a particular application.

Disorder or Disadvantage: Investigating the Tension Between Neighborhood Social Structure and the Physical Environment on Local Violence

2021 ◽  
pp. 073401682199679
Author(s):  
Michael S. Barton ◽  
Matthew A. Valasik ◽  
Elizabeth Brault
Keyword(s):  
Crime Prevention ◽  
Physical Environment ◽  
Structural Characteristics ◽  
Lethal Violence ◽  
Social Structural ◽  
Neighborhood Risk ◽  
Short Run ◽  
Relationship Of ◽  
The Relationship

A renewed interest in understanding the relationship of the built environment with neighborhood crime patterns has encouraged researchers to utilize novel methods (e.g., risk terrain modeling) to better examine the influence of environmental risk factors on types of crime. The current study engages with this research by operationalizing neighborhoods using Hipp and Boessen’s egohood strategy and using Drawve’s aggregate neighborhood risk of crime measure to assess the relationship of a neighborhood’s physical environment with its spatial vulnerability of experiencing a homicide. Findings demonstrate that the physical environment was a significant predictor of neighborhood homicide; however, social structural neighborhood characteristics were more important. This suggests crime prevention strategies like crime prevention though environmental design or blight remediation may provide prudent and straightforward methods to inhibit lethal violence in a community in the short run, but that addressing a neighborhood’s social structural characteristics may be more effective at reducing homicides in the long term.

scholarly journals Design of Customized TPU Lattice Structures for Additive Manufacturing: Influence on the Functional Properties in Elastic Products

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4341
Author(s):  
Sergio de la Rosa ◽  
Pedro F. Mayuet ◽  
José Ramón Méndez Salgueiro ◽  
Lucía Rodríguez-Parada
Keyword(s):  
Lattice Structure ◽  
Reaction Force ◽  
Statistical Treatment ◽  
Lattice Structures ◽  
Compression Process ◽  
Element Simulation ◽  
Relationship Of ◽  
The Relationship ◽  
Manufacturing Parameters ◽  
Elastic Lattice

This work focuses on evaluating and establishing the relationship of the influence of geometrical and manufacturing parameters in stiffness of additively manufactured TPU lattice structures. The contribution of this work resides in the creation of a methodology that focuses on characterizing the behavior of elastic lattice structures. Likewise, resides in the possibility of using the statistical treatment of results as a guide to find favorable possibilities within the range of parameters studied and to predict the behavior of the structures. In order to characterize their behavior, different types of specimens were designed and tested by finite element simulation of a compression process using Computer Aided Engineering (CAE) tools. The tests showed that the stiffness depends on the topology of the cells of the lattice structure. For structures with different cell topologies, it has been possible to obtain an increase in the reaction force against compression from 24.7 N to 397 N for the same manufacturing conditions. It was shown that other parameters with a defined influence on the stiffness of the structure were the temperature and the unit size of the cells, all due to the development of fusion mechanisms and the variation in the volume of material used, respectively.

Analysis of OSB Mat Structure Using CAD Technology

2010 ◽  
Vol 113-116 ◽  
pp. 1619-1623
Author(s):  
Peng Li ◽  
Yu Bo Tao ◽  
Feng Hu Wang ◽  
Sun Guo Wang
Keyword(s):  
Computer Aided Design ◽  
Structural Characteristics ◽  
Three Dimensional ◽  
Three Dimensional Model ◽  
Forming Process ◽  
Strand Orientation ◽  
Realistic Description ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

For further researching the structural characteristics of Orientated strand board (OSB) mat, a three-dimensional model was developed using computer-aided design (CAD) technology to simulate behaviors of individual strands in the mat-forming process. This model provided a more realistic description of the mat structure than the previous simulations in using varied strand geometry and different types of strand orientation, defining strand location, and solving the problem of edge effect. This model can be used to analyze the impact of strand orientation on the number of strand overlaps, and to identify the relationship of strand orientation and the horizontal voids distribution in the mat. Information provided by this model is the basis of further studying the effect of the mat formation on panel void characteristics, and the relationship of the voids volume to panel properties.

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