Novel hierarchical structure of MoS2/TiO2/Ti3C2Tx composites for dramatically enhanced electromagnetic absorbing properties

AbstractIn order to prevent the microwave leakage and mutual interference, more and more microwave absorbing devices are added into the design of electronic products to ensure its routine operation. In this work, we have successfully prepared MoS2/TiO2/Ti3C2Tx hierarchical composites by one-pot hydrothermal method and focused on the relationship between structures and electromagnetic absorbing properties. Supported by comprehensive characterizations, MoS2 nanosheets were proved to be anchored on the surface and interlayer of Ti3C2Tx through a hydrothermal process. Additionally, TiO2 nanoparticles were obtained in situ. Due to these hierarchical structures, the MoS2/TiO2/Ti3C2Tx composites showed greatly enhanced microwave absorbing performance. The MoS2/TiO2/Ti3C2Tx composites exhibit a maximum reflection loss value of −33.5 dB at 10.24 GHz and the effective absorption bandwidth covers 3.1 GHz (13.9–17 GHz) at the thickness of 1.0 mm, implying the features of wide frequency and light weight. This work in the hierarchical structure of MoS2/TiO2/Ti3C2Tx composites opens a promising door to the exploration of constructing extraordinary electromagnetic wave absorbents.

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Novel Hierarchical Structure of MoS2/TiO2/Ti3C2Tx Composites for Dramatically Enhanced Electromagnetic Absorbing Properties

10.21203/rs.3.rs-184920/v1 ◽

2021 ◽

Author(s):

Heng Du ◽

Qipeng Zhang ◽

Biao Zhao ◽

Frank Marken ◽

Qiancheng Gao ◽

...

Keyword(s):

Hierarchical Structure ◽

Hydrothermal Process ◽

Hierarchical Structures ◽

One Pot ◽

Electronic Products ◽

The Hierarchical Structure ◽

Hierarchical Composites ◽

Microwave Absorbing ◽

The Relationship

Abstract In order to prevent the microwave leakage and mutual interference, more and more microwave absorbing devices are added into the design of electronic products to ensure its routine operation. In this work, we have successfully prepared MoS2/TiO2/Ti3C2Tx hierarchical composites by one-pot hydrothermal method and focused on the relationship between structures and electromagnetic absorbing properties. Supported by comprehensive characterizations, MoS2 nanosheets were proved to be anchored on the surface and interlayer of Ti3C2Tx through a hydrothermal process. Additionally, TiO2 nanoparticles were obtained in situ. Due to these hierarchical structures, the MoS2/TiO2/Ti3C2Tx composites showed greatly enhanced microwave absorbing performance. The MoS2/TiO2/Ti3C2Tx composites exhibit a maximum reflection loss value of −33.5 dB at 10.24 GHz and the effective absorption bandwidth covers 3.1 GHz (13.9–17 GHz) at the thickness of 1.0 mm, implying the features of wide frequency and light weight. This work in the hierarchical structure MoS2/TiO2/Ti3C2Tx composites opens a promising door to the exploration of constructing extraordinary electromagnetic wave absorbents.

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Perceiving Hierarchical Structures in Nonrepresentational Paintings

Empirical Studies of the Arts ◽

10.2190/8yj4-tgu8-q32r-9fbl ◽

1998 ◽

Vol 16 (1) ◽

pp. 59-70 ◽

Cited By ~ 15

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.

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

Volume 2: 26th Design Automation Conference ◽

10.1115/detc2000/dac-14526 ◽

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.

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Optimal Сontrol of Technological Process of Carburization of Automotive Gears

Materials Science Forum ◽

10.4028/www.scientific.net/msf.870.647 ◽

2016 ◽

Vol 870 ◽

pp. 647-653 ◽

Cited By ~ 4

Author(s):

M.Yu. Livshitc ◽

E.A. Yakubovich

Keyword(s):

Technological Process ◽

Hierarchical Structure ◽

Quality Criteria ◽

Hardened Layer ◽

Optimal Parameters ◽

Carbon Distribution ◽

Global Quality ◽

The Hierarchical Structure ◽

Technological Impact ◽

The Relationship

This article presents the basis for and implementation of an approach to the development of the individualised gas carburization technology relying on optimisation of the process of carburizing surfaces of workpieces and taking into consideration working requirements. The approach is based on the hierarchical structure of carburization models, utilising the decomposition of global quality criteria and reflecting the relationship between the quality values of the hardened layer and the parameters of a technological impact on the workpiece. Taking the example of carburization of automobile gears, optimal parameters for the carburization technology are defined which minimise the duration of the process and maximise the precision of approximation to a given carbon distribution in the hardened layer within technical limitations.

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TreeSummarizedExperiment: a S4 class for data with hierarchical structure

F1000Research ◽

10.12688/f1000research.26669.1 ◽

2020 ◽

Vol 9 ◽

pp. 1246

Author(s):

Ruizhu Huang ◽

Charlotte Soneson ◽

Felix G.M. Ernst ◽

Kevin C. Rue-Albrecht ◽

Guangchuang Yu ◽

...

Keyword(s):

Hierarchical Structure ◽

Hierarchical Structures ◽

Cell Types ◽

Profile Data ◽

Biological Profile ◽

Data Manipulation ◽

The Hierarchical Structure ◽

R Packages ◽

Popular Classes ◽

Tree Representations

Data organized into hierarchical structures (e.g., phylogenies or cell types) arises in several biological fields. It is therefore of interest to have data containers that store the hierarchical structure together with the biological profile data, and provide functions to easily access or manipulate data at different resolutions. Here, we present TreeSummarizedExperiment, a R/S4 class that extends the commonly used SingleCellExperiment class by incorporating tree representations of rows and/or columns (represented by objects of the phylo class). It follows the convention of the SummarizedExperiment class, while providing links between the assays and the nodes of a tree to allow data manipulation at arbitrary levels of the tree. The package is designed to be extensible, allowing new functions on the tree (phylo) to be contributed. As the work is based on the SingleCellExperiment class and the phylo class, both of which are popular classes used in many R packages, it is expected to be able to interact seamlessly with many other tools.

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Embedding Hierarchical Structures for Venue Category Representation

ACM Transactions on Information Systems ◽

10.1145/3478285 ◽

2022 ◽

Vol 40 (3) ◽

pp. 1-29

Author(s):

Meng Chen ◽

Lei Zhu ◽

Ronghui Xu ◽

Yang Liu ◽

Xiaohui Yu ◽

...

Keyword(s):

Hierarchical Structure ◽

Hierarchical Structures ◽

Category Representation ◽

Semantic Relationships ◽

The Hierarchical Structure ◽

Sequential Information ◽

Location Based Social Networks ◽

Low Dimensional ◽

The Given ◽

Embedding Methods

Venue categories used in location-based social networks often exhibit a hierarchical structure, together with the category sequences derived from users’ check-ins. The two data modalities provide a wealth of information for us to capture the semantic relationships between those categories. To understand the venue semantics, existing methods usually embed venue categories into low-dimensional spaces by modeling the linear context (i.e., the positional neighbors of the given category) in check-in sequences. However, the hierarchical structure of venue categories, which inherently encodes the relationships between categories, is largely untapped. In this article, we propose a venue C ategory E mbedding M odel named Hier-CEM , which generates a latent representation for each venue category by embedding the Hier archical structure of categories and utilizing multiple types of context. Specifically, we investigate two kinds of hierarchical context based on any given venue category hierarchy and show how to model them together with the linear context collaboratively. We apply Hier-CEM to three tasks on two real check-in datasets collected from Foursquare. Experimental results show that Hier-CEM is better at capturing both semantic and sequential information inherent in venues than state-of-the-art embedding methods.

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Structure Organization of Hierarchical Fuzzy Model Using Genetic Algorithm

Journal of Robotics and Mechatronics ◽

10.20965/jrm.1995.p0029 ◽

1995 ◽

Vol 7 (1) ◽

pp. 29-35

Author(s):

Toshio Fukuda ◽

◽

Yasuhisa Hasegawa ◽

Koji Shimojima

Keyword(s):

Genetic Algorithm ◽

Hierarchical Structure ◽

Back Propagation ◽

Fuzzy Model ◽

Numerical Data ◽

Fuzzy Rules ◽

Input And Output ◽

The Hierarchical Structure ◽

Input Variables ◽

The Relationship

This paper proposes a method to organize the hierarchical structure of fuzzy model using the Genetic Algorithm and back-propagation method. The number of fuzzy rules increases exponentially with the number of input variables. Thus, a fuzzy system with many input variables has an extremely large number of fuzzy rules. Hierarchical structure of fuzzy reasoning is one of the methods to reduce the number of fuzzy rules and membership functions. However, it is very difficult to organize the hierarchical structure because the hierarchical structure cannot be constructed without considering the relationship among input and output variables. The proposed method can organize the suitable hierarchical structure for the relationship among input and output variables in teaching numerical data. It is based on the Genetic Algorithm with an evaluation function as a strategy that adopts a system with fewer fuzzy rules and more accurate outputs. The proposed method is applied to the approximation problems of multi-dimensional nonlinear functions in order to demonstrate its effectiveness.

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

Journal of Mechanical Design ◽

10.1115/1.1666889 ◽

2004 ◽

Vol 126 (2) ◽

pp. 217-224 ◽

Cited By ~ 12

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

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.

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Zn-P Co-Modified Hierarchical ZSM-5 Zeolites Directly Synthesized via Dry Gel Conversion for Enhanced Methanol to Aromatics Reaction

Catalysts ◽

10.3390/catal11111388 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1388

Author(s):

Youhe Wang ◽

Zhihong Li ◽

Chang Dai ◽

Ningning Du ◽

Tingting Li ◽

...

Keyword(s):

Hierarchical Structure ◽

Lewis Acid ◽

Hierarchical Structures ◽

Acid Sites ◽

Impregnation Method ◽

Lewis Acid Sites ◽

Dry Gel Conversion ◽

The Hierarchical Structure ◽

Unique Method ◽

Benzene Toluene

A unique method to prepare Zn-P co-modified hierarchical ZSM-5 zeolites was developed. The ZSM-5 zeolite was directly synthesized by a dry gel conversion without adding any templates or seeds. Afterwards, the hierarchical structure was endowed to the ZSM-5 zeolite by the sequential desilication-dealumination. Zn and P species were then introduced into the hierarchical ZSM-5 zeolites by the impregnation method and their activity in methanol to aromatics process was investigated. It was found that the Zn-P co-modified hierarchical ZSM-5 zeolites possessed more Zn-related Lewis acid sites, and the ratio of Zn(OH)+/ZnO was increased. The catalytic evaluation results revealed that the benzene, toluene and xylene (BTX) and aromatics selectivity were significantly improved from 20.59% and 29.41% of pristine ZSM-5 zeolite to 28.12% and 41.88% of Zn-P co-modified hierarchical counterpart (1.5Zn0.3P/HZSM-5), respectively. Owing to the introduced highly stable Zn-P co-modified hierarchical structures, the lifetime (conversion not less than 99%) of ZSM-5 zeolite during methanol to aromatics reaction was increased from 6 h to 18 h.

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