Statistical Approach to Identify Key Growth Parameters of the Novel Graphene Growth PVD Processes

2021 ◽  
pp. 65-89
Author(s):  
Cher-Ming Tan ◽  
Udit Narula ◽  
Vivek Sangwan
Keyword(s):  
Statistical Approach ◽  
Growth Parameters ◽  
The Novel ◽  
Graphene Growth

scholarly journals Dopant-stimulated growth of GaN nanotube-like nanostructures on Si(111) by molecular beam epitaxy

2018 ◽  
Vol 9 ◽  
pp. 146-154 ◽  
Author(s):  
Alexey D Bolshakov ◽  
Alexey M Mozharov ◽  
Georgiy A Sapunov ◽  
Igor V Shtrom ◽  
Nickolay V Sibirev ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Surface Density ◽  
Molecular Beam ◽  
Growth Parameters ◽  
Elongation Rate ◽  
The Novel ◽  
Geometrical Properties ◽  
Transmission Electron ◽  
Si Doped ◽  
Aln Buffer

In this paper we study growth of quasi-one-dimensional GaN nanowires (NWs) and nanotube (NT)-like nanostructures on Si(111) substrates covered with a thin AlN layer grown by means of plasma-assisted molecular beam epitaxy. In the first part of our study we investigate the influence of the growth parameters on the geometrical properties of the GaN NW arrays. First, we find that the annealing procedure carried out prior to deposition of the AlN buffer affects the elongation rate and the surface density of the wires. It has been experimentally demonstrated that the NW elongation rate and the surface density drastically depend on the substrate growth temperature, where 800 °C corresponds to the maximum elongation rate of the NWs. In the second part of the study, we introduce a new dopant-stimulated method for GaN nanotube-like nanostructure synthesis using a high-intensity Si flux. Transmission electron microscopy was used to investigate the morphological features of the GaN nanostructures. The synthesized structures have a hexagonal cross-section and possess high crystal quality. We propose a theoretical model of the novel nanostructure formation which includes the role of the dopant Si. Some of the Si-doped samples were studied with the photoluminescence (PL) technique. The analysis of the PL spectra shows that the highest value of donor concentration in the nanostructures exceeds 5∙1019 cm−3.

scholarly journals ANALISIS BENTUK PENYIASATAN STRUKTUR PADA NOVEL RUMAH TANPA JENDELA KARYA ASMA NADIA

2020 ◽  
Vol 5 (1) ◽  
pp. 37-48
Author(s):  
Kapsah Kapsah ◽  
Ade Husnul Mawadah ◽  
Sundawati Tisnasari
Keyword(s):  
Statistical Approach ◽  
Structural Alignment ◽  
Analysis Data ◽  
Data Parallelism ◽  
The Novel ◽  
Detailed Data ◽  
Library Research ◽  
Qualitative Descriptive ◽  
Rhetorical Questions ◽  
Descriptive Method

This study analyzes the novel using a statistical approach. The research method is a qualitative-descriptive method. The purpose of this study is to describe the form of structuring that is contained in the novel House without Windows by Asma Nadia. As for data collected through library research research techniques, see techniques and note techniques. The data used in this study are excerpts from the novel that are the source of the data. The source of the data in this study is the novel House without Windows by Asma Nadia. In addition, the data obtained are classified based on their shape in order to facilitate the analysis. Data analyzed are data that have been tested for validity by validators who are experts in their fields. Referring to the knife analysis of the stylistic approach, we found a form of structural alignment. So, it can be concluded that the form of structuring data obtained from the novel House without Window by Asma Nadia 55 data with detailed data, 9 data repetition, 4 data parallelism, 7 data anaphora, 9 data antithesis, 7 data alliteration, climax as much as 1 data, asindeton as much as 13 data, rhetorical questions as much as 4 data, and polisidenton as much as 1 data. While the least data found was polysindeton and climax data, and no anticlimactic data was found.

scholarly journals A Computational Growth Framework for Biological Tissues: Application to Growth of Aortic Root Aneurysm Repaired by the V-shape Surgery

2021 ◽  
Author(s):  
Hai Dong ◽  
Minliang Liu ◽  
Tongran Qin ◽  
Liang Liang ◽  
Bulat Ziganshin ◽  
...  
Keyword(s):  
Aortic Root ◽  
Growth Parameters ◽  
Optimization Procedure ◽  
Biological Tissues ◽  
Aortic Aneurysms ◽  
Patient Specific ◽  
Aortic Tissue ◽  
The Novel ◽  
Post Surgery

Ascending aortic aneurysms (AsAA) often include the dilatation of sinotubular junction (STJ) which usually leads to aortic insufficiency. The novel surgery of the V-shape resection of the noncoronary sinus, for treatment of AsAA with root ectasia, has been shown to be a simpler procedure compared to traditional surgeries. Our previous study showed that the repaired aortic root aneurysms grew after the surgery. In this study, we developed a novel computational growth framework to model the growth of the aortic root repaired by the V-shape surgery. Specifically, the unified-fiber-distribution (UFD) model was applied to describe the hyperelastic deformation of the aortic tissue. A novel kinematic growth evolution law was proposed based on existing observations that the growth rate is linearly dependent on the wall stress. Moreover, we also obtained patient-specific geometries of the repaired aortic root post-surgery at two follow-up time points (Post1 and Post2) for 5 patients, based on clinical CT images. The novel computational growth framework was implemented into the Abaqus UMAT user subroutine and applied to model the growth of the aortic root from Post1 to Post2. Patient-specific growth parameters were obtained by an optimization procedure. The predicted geometry and stress of the aortic root at Post2 agree well with the in vivo results. The novel computational growth framework and the optimized growth parameters could be applied to predict the growth of repaired aortic root aneurysms for new patients and to optimize repair strategies for AsAA.

scholarly journals Analyzing Stress as a Multivariate Phenotype

2020 ◽  
Vol 60 (1) ◽  
pp. 70-78
Author(s):  
Rory S Telemeco ◽  
Eric J Gangloff
Keyword(s):  
Statistical Approach ◽  
Single Point ◽  
The Novel ◽  
Multivariate Statistical ◽  
Theoretical Understanding ◽  
Online Appendix ◽  
Statistical Framework ◽  
Multiple Biomarkers ◽  
General Statistical ◽  
Multivariate Theory

Abstract The stress phenotype is multivariate. Recent advances have broadened our understanding beyond characterizing the stress response in a single dimension. Simultaneously, the toolbox available to ecophysiologists has expanded greatly in recent years, allowing the measurement of multiple biomarkers from an individual at a single point in time. Yet these advances—in our conceptual understanding and available methodologies—have not yet been combined in a unifying multivariate statistical framework. Here, we offer a brief review of the multivariate stress phenotype and describe a general statistical approach for analysis using nonparametric multivariate analysis of variance with residual randomization in permutation procedures (RRPP) implemented using the “RRPP” package in R. We also provide an example illustrating the novel insights that can be gained from a holistic multivariate approach to stress and provide a tutorial for how we analyzed these data, including annotated R code and a guide to interpretation of outputs (Online Appendix 1). We hope that this statistical methodology will provide a quantitative framework facilitating the unification of our theoretical understanding and empirical observations into a quantitative, multivariate theory of stress.

scholarly journals Atmospheric Pressure Catalytic Vapor Deposition of Graphene on Liquid In and Cu-In Alloy Substrates

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1318
Author(s):  
Maryam A. Saeed ◽  
Ian A. Kinloch ◽  
Brian Derby
Keyword(s):  
Atmospheric Pressure ◽  
Defect Density ◽  
Growth Parameters ◽  
Chemical Vapour ◽  
Growth Conditions ◽  
Growth Time ◽  
Graphene Growth ◽  
Graphene Films ◽  
Reactive Gases

Liquid substrates are great candidates for the growth of high-quality graphene using chemical vapour deposition (CVD) due to their atomically flat and defect free surfaces. A detailed study of graphene growth using atmospheric pressure CVD (APCVD) on liquid indium (In) was conducted. It was found that the effect of the growth parameters on the quality of the graphene produced is highly dependent on the properties of the substrate used. A short residence time of 6.8 sec for the reactive gases led to a high graphene quality, indicating the good catalytic behaviour of In. The role of hydrogen partial pressure was found to be crucial, with monolayer and bilayer graphene films with a low defect density obtained at low PH2 (38.6 mbar), whilst more defective, thicker graphene films with a partial coverage being obtained at high PH2 (74.3 mbar). The graphene deposition was insensitive to growth time as the graphene growth on liquid In was found to self-limit to bilayer. For further investigation, five compositions of Cu-In alloys were made by arc-melting. Graphene was then grown using the optimum conditions for In and the quality of the graphene was found to degrade with increasing Cu wt.%. This work will aid the future optimisation of the growth conditions based upon the substrate’s properties.

scholarly journals Modify Manhattan Distance for Image Similarity

2020 ◽  
Vol 2 (4) ◽  
pp. 12-16
Author(s):  
Tasaddi Maalak Hanoun ◽  
Kadhim M. Hashim
Keyword(s):  
Statistical Approach ◽  
Similarity Index ◽  
Structural Similarity ◽  
Image Similarity ◽  
Manhattan Distance ◽  
The Novel ◽  
Structural Similarity Index ◽  
Significant Difference ◽  
Index Measure ◽  
Similarity Method

A New measure is proposed for assessing the similarity among gray-scale images. The well-known Structural Similarity Index Measure (SSIM) has been designed using a statistical approach that fails under significant noise (lowPSNR). The proposed measure, denoted by Manhattan distance and STD, uses a combination of two parts: the first part is the Geometric method, while the second part is based on the statistical feature. The concept of manhattan distance is used in the geometric part. The new measure shows the advantages of statistical approaches and geometric approaches. The proposed similarity method is an outcome for the human face. The novel measure outperforms the classical SSIM in detecting image similarity at low PSNR, with a significant difference in performance. AMS subject classification:

scholarly journals An Opinion Regarding Equivalence Testing for Evaluating Measurement Agreement

2019 ◽  
pp. 1-4
Author(s):  
Manolis Adamakis
Keyword(s):  
Physical Activity ◽  
Statistical Analysis ◽  
Statistical Approach ◽  
Equivalence Testing ◽  
The Novel ◽  
Mixed Design ◽  
Robust Approach ◽  
Mixed Anova ◽  
Activity Measures ◽  
Mixed Design Anova

The novel statistical approach ‘equivalence testing’ has been proposed in order to statistically examine agreement between different physical activity measures. By using this method, researchers argued that it is possible to determine whether a method is significantly equivalent to another method. Recently, equivalence testing was supported with the use of 90% confidence interval, obtained from a mixed ANOVA, which I believe is a more robust approach. This paper further discusses the use of this method in comparison to a more well-established statistical analysis (i.e. mixed design ANOVA), as well as various limitations and arbitrary assumptions in order to perform this analysis. The paper concludes with some remarks and considerations for future use in similar approaches.

Studies of Ge/Si(100) and Observation of Atomic Steps on Si(100) using Biassed Secondary Electron Imaging in a UHV STEM

1990 ◽  
Vol 48 (1) ◽  
pp. 308-309
Author(s):  
Mohan Krishnamurthy ◽  
Jeff S. Drucker ◽  
John A. Venablest
Keyword(s):  
Secondary Electron ◽  
Critical Thickness ◽  
Surface Defects ◽  
Film Growth ◽  
Growth Parameters ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Surface Steps ◽  
Epitaxial Crystal Growth ◽  
Electron Imaging

Secondary Electron Imaging (SEI) has become a useful mode of studying surfaces in SEM[1] and STEM[2,3] instruments. Samples have been biassed (b-SEI) to provide increased sensitivity to topographic and thin film deposits in ultra high vacuum (UHV)-SEM[1,4]; but this has not generally been done in previous STEM studies. The recently developed UHV-STEM ( codenamed MIDAS) at ASU has efficient collection of secondary electrons using a 'parallelizer' and full sample preparation system[5]. Here we report in-situ deposition and annealing studies on the Ge/Si(100) epitaxial system, and the observation of surface steps on vicinal Si(100) using b-SEI under UHV conditions in MIDAS.Epitaxial crystal growth has previously been studied using SEM and SAM based experiments [4]. The influence of surface defects such as steps on epitaxial growth requires study with high spatial resolution, which we report for the Ge/Si(100) system. Ge grows on Si(100) in the Stranski-Krastonov growth mode wherein it forms pseudomorphic layers for the first 3-4 ML (critical thickness) and beyond which it clusters into islands[6]. In the present experiment, Ge was deposited onto clean Si(100) substrates misoriented 1° and 5° toward <110>. This was done using a mini MBE Knudsen cell at base pressure ~ 5×10-11 mbar and at typical rates of 0.1ML/min (1ML =0.14nm). Depositions just above the critical thickness were done for substrates kept at room temperature, 375°C and 525°C. The R T deposits were annealed at 375°C and 525°C for various times. Detailed studies were done of the initial stages of clustering into very fine (∼1nm) Ge islands and their subsequent coarsening and facetting with longer anneals. From the particle size distributions as a function of time and temperature, useful film growth parameters have been obtained. Fig. 1 shows a b-SE image of Ge island size distribution for a R T deposit and anneal at 525°C. Fig.2(a) shows the distribution for a deposition at 375°C and Fig.2(b) shows at a higher magnification a large facetted island of Ge. Fig.3 shows a distribution of very fine islands from a 525°C deposition. A strong contrast is obtained from these islands which are at most a few ML thick and mottled structure can be seen in the background between the islands, especially in Fig.2(a) and Fig.3.

The novel steroidal glycoside from the dried bulb of Allium Macrostemon Bunge inhibits platelet activation

2010 ◽  
Vol 34 (8) ◽  
pp. S33-S33
Author(s):  
Wenchao Ou ◽  
Haifeng Chen ◽  
Yun Zhong ◽  
Benrong Liu ◽  
Keji Chen
Keyword(s):  
Platelet Activation ◽  
The Novel ◽  
Steroidal Glycoside ◽  
Allium Macrostemon
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