<title>Quantitative aberration assessment by a through focal analysis of pattern edge sharpness</title>

Abstract A numerical study was undertaken to examine the effects of utilizing sharper edges for increasing the leakage resistance of advanced labyrinth seal configurations. Such an increase allows the designer to enlarge the extremely small knife clearance, providing a seal with less damage susceptibility at the same leakage rate. The maximum possible leakage resistance increase from changing three cavity edges to perfectly sharp ones was estimated from the present computations. In addition, previous measurements of the edge sharpness effect on the leakage through orifices are appropriately utilized to obtain a rough estimate of the resistance increase for generic seals. The latter allows consideration of a broader range of application. Further, turbulence energy generation contours reveal that only one particular cavity edge needs to be sharpened in order to obtain a significantly increased leakage resistance.

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Image Denoising Using Discrete Wavelet Transform : A Theoretical Framework

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.16.11637 ◽

2018 ◽

Vol 7 (2.16) ◽

pp. 120

Author(s):

Praveen Bhargava ◽

Shruti Choubey ◽

Rakesh Kumar Bhujade ◽

Nilesh Jain

Keyword(s):

Image Denoising ◽

Ultra Sound ◽

Discrete Wavelet ◽

Transform Domain ◽

Hybrid Filter ◽

Edge Sharpness ◽

In Series ◽

Salt And Pepper ◽

Image Type

Noise is a random variation in brightness and color in image or simply we can say that unwanted signals are called noise. The noise is mixed with original signal and cause may troubles. Due to the presence of noise, quality of image is reduced and other features like edge sharpness and pattern recognition are badly affected. In image denoising methods to improve the results a hybrid filter is used for better visualization. The hybrid filter is composed with the combination of three filters connected in series. The hybridization has performed much better in case of salt and pepper type of noise and for most of the medical image type, either MRI, CT, SPECT, Ultra Sound. PSNR values show major improvement in comparison of other existing methods. Future, the results obtained from the presented denoising experiments would be tried to be improved further by using this method with other transform domain methods. Finally, the results are concluded that the proposed approach in terms of PSNR, MSE improvement is outperformed.

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Trading Networks of Malay Merchants and Traders in the Straits of Melaka from 1780 to 1830

Asian Journal of Social Science ◽

10.1163/156853112x632566 ◽

2012 ◽

Vol 40 (1) ◽

pp. 51-82

Author(s):

Nordin Hussin

Keyword(s):

Southeast Asia ◽

18Th Century ◽

Early Modern History ◽

Trace Back ◽

Late 18Th Century ◽

History Of ◽

European Colonialism ◽

Trading Networks ◽

The 19Th Century ◽

Focal Analysis

Abstract Malay merchants and traders played an essential and significant role in the early modern history of trade and commerce in Southeast Asia. Nevertheless records on the history of their entrepreneurship has been hardly written and researched upon. Thus, the main objective of this paper is to trace back the dynamic of Malay trading communities in the late 18th and towards the early decades of the 19th century. The paper would also highlight the importance of Malay traders in early Penang and the survival of Melaka as an important port in the late 18th century. A focal analysis of this study is on the 18th and 19th centuries Malay merchant communities and how their active presence in the Malay waters had given a great impact to the intra-Asian trade in Southeast Asia prior to the period of European colonialism and imperialism.

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ELID Grinding Technology of Nano-Ceramic Scalpel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.468-471.1560 ◽

2012 ◽

Vol 468-471 ◽

pp. 1560-1563 ◽

Cited By ~ 1

Author(s):

Ji Cai Kuai ◽

Fei Hu Zhang ◽

Ya Zhong Liu

Keyword(s):

Surface Roughness ◽

Wear Resistance ◽

High Hardness ◽

High Wear Resistance ◽

Preparation Technology ◽

Elid Grinding ◽

High Toughness ◽

Edge Sharpness ◽

Cutting Experiment ◽

Promising Application

As the grain size of nano ceramic has reached nanometer grade, it possesses high hardness, high wear resistance and high toughness. Therefore, the scalpel made by nano ceramic has the virtue of high wear resistance, good corrosion resistance, long service life, non-toxic, non-static, sharp edge and so on, but the processing of this kind of scalpel is extremely difficult. This paper prepares the nano-ceramic scalpel by using ELID grinding technology, and also studies the thickness, surface roughness, edge sharpness of scalpel. The research results show that the thickness of prepared scalpel is 0.3 mm, the surface roughness is 6-60 nm and the edge radius is 200 nm, the cutting experiment on suture shows that this scalpel can meet the requirements of international standard for medical scalpel when the cutting force is less than 0.8 N. This further proves that the ELID grinding technology is suitable for the preparation of nano-ceramic scalpel. The preparation technology and technological equipment of nano-ceramic scalpel are proposed on the basis of above achievements, and this technology possesses promising application prospect.

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