scholarly journals Kinetics of Carbon Nanotubes and Graphene Growth on Iron and Steel: Evidencing the Mechanisms of Carbon Formation

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 143
Author(s):  
Luís Sousa Lobo ◽  
Sónia A. C. Carabineiro
Keyword(s):  
Carbon Nanotubes ◽  
Research Work ◽  
Research Area ◽  
Carbon Formation ◽  
Iron And Steel ◽  
Surface Catalysis ◽  
Catalytically Active ◽  
Active Research ◽  
Detailed Kinetics ◽  
Time Required

Carbon formation on steel has recently become an active research area with several important applications, using either carbon nanotubes (CNTs) or graphene structures. The production of vertically aligned CNT (VACNT) forests with combined metals has been explored with important results. Detailed kinetics is the best approach to understand a mechanism. The growth behavior seems complex but can be simplified through the knowledge of the three more common alternative reaction mechanisms/routes. The time required to optimize the production and properties might be reduced. The mechanistic proposal reported in 1971 was better explained recently. The volcano shape Arrhenius plot reported is observed only when Fe, Co, and Ni are used as reaction catalysts. Other metals are catalytically active at higher temperatures, following a different route, which does not require surface catalysis decomposition of the reactive gas. C2H2 and low olefins react well, but CH4 is not reactive via this surface catalysis route. Optimizing production of CNTs, research work is usually based on previous experience, but solid-state science-based studies are available.

scholarly journals Combined global and local semantic feature–based image retrieval analysis with interactive feedback

2019 ◽  
Vol 53 (1-2) ◽  
pp. 3-17
Author(s):  
A Anandh ◽  
K Mala ◽  
R Suresh Babu
Keyword(s):  
Wavelet Transform ◽  
Image Retrieval ◽  
Research Work ◽  
Research Area ◽  
Content Based Image Retrieval ◽  
Image Retrieval System ◽  
False Image ◽  
Active Research ◽  
High Level ◽  
Interactive Feedback

Nowadays, user expects image retrieval systems using a large database as an active research area for the investigators. Generally, content-based image retrieval system retrieves the images based on the low-level features, high-level features, or the combination of both. Content-based image retrieval results can be improved by considering various features like directionality, contrast, coarseness, busyness, local binary pattern, and local tetra pattern with modified binary wavelet transform. In this research work, appropriate features are identified, applied and results are validated against existing systems. Modified binary wavelet transform is a modified form of binary wavelet transform and this methodology produced more similar retrieval images. The proposed system also combines the interactive feedback to retrieve the user expected results by addressing the issues of semantic gap. The quantitative evaluations such as average retrieval rate, false image acceptation ratio, and false image rejection ratio are evaluated to ensure the user expected results of the system. In addition to that, precision and recall are evaluated from the proposed system against the existing system results. When compared with the existing content-based image retrieval methods, the proposed approach provides better retrieval accuracy.

Applying Fuzzy Logic for Optimal Placement of XBOX Kinect Sensors for Industrial Applications

2012 ◽  
Vol 628 ◽  
pp. 433-439 ◽  
Author(s):  
Nima Rafibakhsh ◽  
H. Felix Lee ◽  
Jie Gong ◽  
Hoo Sang Ko ◽  
Arefeh Mohammadi
Keyword(s):  
Fuzzy Logic ◽  
Real Time ◽  
Research Work ◽  
Research Area ◽  
Industrial Applications ◽  
Optimal Placement ◽  
Work Place ◽  
Manufacturing Operations ◽  
Xbox Kinect ◽  
Active Research

Automated acquisition of sensing data is an active research area in manufacturing domain. A great deal of research work has been focused on automated data acquisitionapplied to various subjects related to manufacturing operations such as safety, performance improvement, monitoring and layout planning. Laser scanners including Time of Flight cameras play a significant role in real time or near real time decision makings in manufacturing automation. To establish an automated sensing system in a work place, enough test data should be available regarding the performance characteristics. This paper investigates the performance of Microsoft XBOX Kinect on spatial modeling in large jobsites, and employs fuzzy logic to find optimal placement of Kinect sensors that gives the best resolution.

Computer Graphics Modeling for Virtual Environments

1995 ◽  
Author(s):  
Mark Green ◽  
Hanqiu Sun
Keyword(s):  
Computer Graphics ◽  
Virtual Environments ◽  
Real World ◽  
Research Area ◽  
Mathematical Representation ◽  
The Real ◽  
Modelling Techniques ◽  
Active Research ◽  
Time Required ◽  
Individual Objects

Modelling is currently one of the most important areas in virtual environments research (Bishop et al., 1992). Of all the software areas, this is the area that we know the least about. Modelling has been an active research area in computer graphics for many decades, and is still a major research area. Many of the modelling issues addressed in computer graphics and virtual environments are also of concern to researchers in robotics, mechanical engineering and biomechanics, so progress in modelling can have an impact on many fields. Modelling is difficult since most of the objects that we would like to model, such as people, animals, and airplanes, are quite complex. They have a large amount of geometrical detail and move in complex ways. This difficulty is compounded by the different fields that use modelling techniques, since each field has its own requirements and priorities. For example, it is highly unlikely that the same model of a human figure would be optimal for applications in both virtual environments and biomechanics. The following criteria can be used as a basis for evaluating different modelling techniques. Accuracy. The model should be an accurate representation of the real-world object. Ideally, we would like all of our models to be precise representations of the real-world objects, and not simply approximations to them. But, in reality accuracy comes with a price, usually increased display time or memory usage. The amount of accuracy required often depends upon the application. For example, in some applications it is acceptable to approximate a sphere with a large number of polygons, but for a large number of computer-aided design (CAD) applications the precise mathematical representation of the sphere is required. Since the polygonal representation can be drawn faster, it is often used in applications where display speed is more important than accuracy. Display speed. Many applications place restrictions on the time available to display individual objects. In the case of interactive applications, short display times increase the level of interaction between the user and the model. In large CAD applications there may be many objects, therefore, the time required to display individual objects becomes an important consideration in the usability of the application even if a high level of interactivity is not required.

Pre-deployment Strategy for Maximizing Barrier Coverage in Wireless Sensor Network

2020 ◽  
Vol 10 ◽  
Author(s):  
Vinay Chowdary ◽  
Amit Kumar Mondal ◽  
Abhinav Sharma ◽  
Shiv Capoor
Keyword(s):  
Wireless Sensors ◽  
Research Area ◽  
Convergence Time ◽  
Wireless Sensor ◽  
Barrier Coverage ◽  
Random Deployment ◽  
Deployment Strategy ◽  
Active Research ◽  
Time Required ◽  
Active Research Area

Purpose: Barrier Coverage in Wireless Sensors Networks has been an active research area. Maximizing number of barriers formed after initial random deployment depends on deployment strategies used. Where existing works rely on sensor relocation after initial random deployment to maximize barrier coverage, authors in this article proposed a novel Minimum Radius Algorithm (MRA), a first of its kind where no two nodes, will be deployed within the non-overlap radius (OR). Results: The simulation results of the proposed algorithm proves that, MRA outperforms its counterpart not only in the case of maximizing barrier count but also in case convergence time required by network to form barriers. Extensive simulations are carried for all network sizes to show the effectiveness of proposed algorithm. Conclusions: This work aims at proposing a pre- deployment strategy that can maximize number of barriers.

Fabrication of Selective Metal Contacts on Single-Walled Carbon Nanotubes for Device Applications

2005 ◽  
Vol 11 (S03) ◽  
pp. 106-109
Author(s):  
I. O. Maciel ◽  
B. R. A. Neves ◽  
A. P. Santos ◽  
C. A. Furtado ◽  
A. S. Ferlauto ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Atomic Force Microscopy ◽  
Single Walled Carbon Nanotubes ◽  
Research Area ◽  
Force Microscopy ◽  
Single Walled Carbon ◽  
Atomic Force ◽  
Sample Characterization ◽  
Active Research ◽  
Walled Carbon Nanotubes

Silicon based devices are expected to achieve the limit of possible downscaling in 10 to 15 years. Thus, the search of new materials to construct smaller, faster and more energy efficient devices has been a very active research area. Carbon nanotubes (CNTs) are very good candidates to construct nanoelectronic and nanophotonic devices [1,2,3] due to unique physical properties, such as its metallic or semiconducting characteristics depending only its diameter and chirality [4,5] and capability of caring high current densities (up to 1010A/cm2). In this work we develop nanofabrication techniques of single-walled carbon nanotubes (SWNTs) based devices using a combination of electron beam and optical lithography with Atomic Force Microscopy (AFM). We used both CVD-grown nanotubes [6] and HipCO-NTs [7] suspended on aqueous solution and deposited on the substrate. Atomic Force Microscopy (AFM) in tapping mode (Multimode Nanoscope IV, Digital Instruments) was used to CVD sample characterization, study of CNT deposition and to localize and index the nanotubes on substrate using lithography patterns as references, making possible to selectively construct metallic contacts on the CNTs.

scholarly journals Region-Based Segmentation and Wiener Pilot-Based Novel Amoeba Denoising Scheme for CT Imaging

Scanning ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Syed Muhammad Umar Talha ◽  
Tariq Mairaj ◽  
Waleed Bin Yousuf ◽  
Jawwad Ali Zahed
Keyword(s):  
Image Quality ◽  
Research Work ◽  
Wiener Filter ◽  
Research Area ◽  
Ct Images ◽  
Image Smoothing ◽  
Similar Region ◽  
Active Research ◽  
Strong Candidate ◽  
Spatially Variant

Computed tomography (CT) is one of the most common and beneficial medical imaging schemes, but the associated high radiation dose injurious to the patient is always a concern. Therefore, postprocessing-based enhancement of a CT reconstructed image acquired using a reduced dose is an active research area. Amoeba- (or spatially variant kernel-) based filtering is a strong candidate scheme for postprocessing of the CT image, which adapts its shape according to the image contents. In the reported research work, the amoeba filtering is customized for postprocessing of CT images acquired at a reduced X-ray dose. The proposed scheme modifies both the pilot image formation and amoeba shaping mechanism of the conventional amoeba implementation. The proposed scheme uses a Wiener filter-based pilot image, while region-based segmentation is used for amoeba shaping instead of the conventional amoeba distance-based approach. The merits of the proposed scheme include being more suitable for CT images because of the similar region-based and symmetric nature of the human body anatomy, image smoothing without compromising on the edge details, and being adaptive in nature and more robust to noise. The performance of the proposed amoeba scheme is compared to the traditional amoeba kernel in the image denoising application for CT images using filtered back projection (FBP) on sparse-view projections. The scheme is supported by computer simulations using fan-beam projections of clinically reconstructed and simulated head CT phantoms. The scheme is tested using multiple image quality matrices, in the presence of additive projection noise. The scheme implementation significantly improves the image quality visually and statistically, providing better contrast and image smoothing without compromising on edge details. Promising results indicate the efficacy of the proposed scheme.

scholarly journals An Enhanced Technique for Fractal Image Compression Using Block Based Features (BBF)

2019 ◽  
Vol 8 (2) ◽  
pp. 90-97
Author(s):  
T. Velumani ◽  
A. R. Karthekeyan ◽  
R. Saveetha
Keyword(s):  
Image Compression ◽  
Research Work ◽  
Research Area ◽  
Experimental Result ◽  
Fractal Image Compression ◽  
Feature Sets ◽  
Fractal Image ◽  
Active Research ◽  
Block Based ◽  
Active Research Area

Image Compression is very active research area specializing on how to compression and decompression of images. The various methods have been proposed for fractal image compression techniques for storage and drawbacks. The complexity in process will affect performance of the existing system to make insufficient. In this paper, the proposed research work presented a block based feature compression of image in the generation of feature sets. The feature sets are generated based such as vertical, horizontal and are extracted from the image based on range and domain blocks. The extracted features are carried out with encoding and decoding the images. The experimental result shows that block based feature method provides better compression ratio and other parameters when compared with the existing methods such as BTC, Wavelet and DCT.

Piezoelectric β-polymorph formation of new textiles by surface modification with coating process based on interfacial interaction on the conformational variation of poly (vinylidene fluoride) (PVDF) chains

2020 ◽  
Vol 91 (3) ◽  
pp. 31301
Author(s):  
Nabil Chakhchaoui ◽  
Rida Farhan ◽  
Meriem Boutaldat ◽  
Marwane Rouway ◽  
Adil Eddiai ◽  
...  
Keyword(s):  
High Efficiency ◽  
Vinylidene Fluoride ◽  
Research Work ◽  
Research Area ◽  
Interfacial Interaction ◽  
Tetraethyl Orthosilicate ◽  
Poly Vinylidene Fluoride ◽  
Carbon Nanofillers ◽  
The Impact ◽  
Advanced Applications

Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β-phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2CH3)4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β-phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β-phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β-phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β-phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.

Document Image Quality Assessment with Relaying Reference to Determine Minimum Readable Resolution for Compression

2020 ◽  
Vol 2020 (9) ◽  
pp. 323-1-323-8
Author(s):  
Litao Hu ◽  
Zhenhua Hu ◽  
Peter Bauer ◽  
Todd J. Harris ◽  
Jan P. Allebach
Keyword(s):  
Image Quality ◽  
Quality Assessment ◽  
Image Quality Assessment ◽  
Research Area ◽  
Input Image ◽  
Quality Score ◽  
Document Image ◽  
Digital Cameras ◽  
Active Research ◽  
Traditional Approaches

Image quality assessment has been a very active research area in the field of image processing, and there have been numerous methods proposed. However, most of the existing methods focus on digital images that only or mainly contain pictures or photos taken by digital cameras. Traditional approaches evaluate an input image as a whole and try to estimate a quality score for the image, in order to give viewers an idea of how “good” the image looks. In this paper, we mainly focus on the quality evaluation of contents of symbols like texts, bar-codes, QR-codes, lines, and hand-writings in target images. Estimating a quality score for this kind of information can be based on whether or not it is readable by a human, or recognizable by a decoder. Moreover, we mainly study the viewing quality of the scanned document of a printed image. For this purpose, we propose a novel image quality assessment algorithm that is able to determine the readability of a scanned document or regions in a scanned document. Experimental results on some testing images demonstrate the effectiveness of our method.

A Person-Centered Design Framework for Serious Games for Dementia

2020 ◽  
Vol 64 (1) ◽  
pp. 18-22
Author(s):  
Bella Yigong Zhang ◽  
Mark Chignell
Keyword(s):  
Theoretical Basis ◽  
Serious Games ◽  
Aging Population ◽  
Research Area ◽  
Design Framework ◽  
Strategic Design ◽  
Health And Wellbeing ◽  
Initial Design ◽  
Active Research ◽  
Active Research Area

With the rapidly aging population and the rising number of people living with dementia (PLWD), there is an urgent need for programming and activities that can promote the health and wellbeing of PLWD. Due to staffing and budgetary constraints, there is considerable interest in using technology to support this effort. Serious games for dementia have become a very active research area. However, much of the work is being done without a strong theoretical basis. We incorporate a Montessori approach with highly tactile interactions. We have developed a person-centered design framework for serious games for dementia with initial design recommendations. This framework has the potential to facilitate future strategic design and development in the field of serious games for dementia.

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