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Article
Publication date: 22 March 2021

Naganagouda Patil, Preethi N. Patil and P.V. Rao

The abnormalities of glaucoma have high impact on deciding and representing the causes that effects severity of blindness in human beings. The simulation experimental results…

Abstract

Purpose

The abnormalities of glaucoma have high impact on deciding and representing the causes that effects severity of blindness in human beings. The simulation experimental results would help the ophthalmologist in diagnosing of glaucoma abnormality accurately. The significant effect of glaucoma has a huge impact on the quality of human life, and its growth rate in world population tremendously increases. Glaucoma is considered as second largest cause for the blindness in the world; hence identification of it marks the importance of its detection at the earliest.

Design/methodology/approach

The prime objective of the work proposed is to build up a human intervention free image preparing framework for glaucoma screening. The disc calculation is assessed on retinal image dataset called retinal Image for glaucoma Analysis. The proposed method briefs a novel optic disc division calculation depending on applying a level-set strategy on a confined optic disc image. In the instance of low quality image, a twofold level set is designed, in which the principal level set is viewed as restriction for the optic disc. To keep the veins from meddling with the level-set procedure, an inpainting strategy has been applied. Also a significant commitment is to include the varieties in notion adopted by the ophthalmologists in distinguishing the disc localization and diagnosing the glaucoma. Most of the past investigations are prepared and tested depending on just a single feature, which can be thought to be one-sided for the ophthalmologist.

Findings

In continuation, the correctness has been determined depending on the quantity of image that matched with the investigation pattern adopted by the ophthalmologist. The 175 retinal images were utilized to test the results of proposed work with the manual markings of ophthalmologists. The error-free calculation in marking the optic disc region and centroid was 98.95% in comparison with the existing result of 87.34%.

Originality/value

In continuation, the correctness has been determined depending on the quantity of image that matched with the investigation pattern adopted by the ophthalmologist. The 175 retinal images were utilized to test the results of proposed work with the manual markings of ophthalmologists. The error-free calculation in marking the optic disc region and centroid was 98.95% in comparison with the existing result of 87.34%.

Details

International Journal of Intelligent Unmanned Systems, vol. 10 no. 1
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 1 March 2005

Robert W. Bogue

This describes a new automated assembly technique, developed by Leica Geosystems and the Swiss Federal Institute of Technology, which allows the automated precision assembly of…

Abstract

Purpose

This describes a new automated assembly technique, developed by Leica Geosystems and the Swiss Federal Institute of Technology, which allows the automated precision assembly of miniature optical components and subsystems.

Design/methodology/approach

Dubbed TRIMO‐SMD (three‐dimensional miniaturised optical surface‐mounted device), this new technique is designed for use with optical components of around 2 mm in diameter such as laser diodes. It uses six‐axis robotic motion, automated optical alignment with cameras and position sensors and laser‐reflow soldering to assemble photonic modules.

Findings

This development has been commercialised and is being used in a production environment by Leica Geosystems. It fixes the optical element into position in just 2 s and the placement accuracy of each component is repeatable to within 1 μm.

Practical implications

This technique has allowed novel micro‐optical assemblies to be produced automatically and has improved the performance and reduced the size and weight of certain precision optical products such as laser rangefinders and Lidar transceiver modules.

Originality/value

This is a new technique which, by allowing the automated, precision assembly of miniature optical components, will benefit companies involved with the manufacture of optical sensing, telecommunications, medical and other products.

Details

Assembly Automation, vol. 25 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 1 April 1997

M. Erickson

Most of HEI’s custom andstandard optical switches require one lens to focus light from an LED and another to collect andconcentrate that light onto a photoelectric diode. Plastic…

120

Abstract

Most of HEI’s custom and standard optical switches require one lens to focus light from an LED and another to collect and concentrate that light onto a photoelectric diode. Plastic lenses are typically glued into apertures in polycarbonate housings using a two ‐part room temperature cured adhesive. To reduce cost and increase productivity, lenses are fabricated in the apertures using an ultraviolet cured clear adhesive. This process eliminates the cost of moulded plastic lenses and reduces cure time from 24 hours to less than a minute. One of the custom optical applications requires bonding a coated glass cover over a cavity containing optical sensors and circuitry. Gas expansion causes ‘blow‐outs’ when heat cured adhesives are used and room temperature cured adhesives add a day to turnaround time. An ultraviolet cured adhesive increases productivity by eliminating blow‐outs and reducing turnaround time. A unique process has been developed in which the glass cover is placed over the cavity in a vacuum bell jar.

Details

Microelectronics International, vol. 14 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 June 1969

G.F. SHOTTER

THE FRICTION developed in footstep type meter and instrument bearings have always presented a difficult problem to designers due to the mechanical severity, i.e., very high…

Abstract

THE FRICTION developed in footstep type meter and instrument bearings have always presented a difficult problem to designers due to the mechanical severity, i.e., very high specific pressures, and the information given in this paper is the result of over thirty years of research on the problem carried out on behalf of the Electrical Research Association and also for the Northmet Laboratories.

Details

Industrial Lubrication and Tribology, vol. 21 no. 6
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 1 October 1997

W.M. Yu, S.C. Harlock, G.A.V. Leaf and K.W. Yeung

Describes the setting up of a moiré topographic system to measure three‐dimensional convex and concave surfaces of moulded brassière cups. The essential features of the system…

577

Abstract

Describes the setting up of a moiré topographic system to measure three‐dimensional convex and concave surfaces of moulded brassière cups. The essential features of the system consisted of a photographic instrument which precisely controlled the position of the light source, the camera, the grid and the cup sample. As the uniformity of the grid was most crucial to produce a high contrast moiré picture, a photochemical‐machined grid plate was developed, and a pneumatic grid translation device was incorporated into the system to produce a clear image. The tolerance of the instrumental error was derived by the law of error propagation and the confidence with the moiré set‐up was assured.

Details

International Journal of Clothing Science and Technology, vol. 9 no. 4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 1943

William Schroeder and Thomas H. Hazlett

THE modern aeroplane is constructed largely from sheet metal. As such, the most important production problems are those of sheet metal forming, and assembling. Production is here…

Abstract

THE modern aeroplane is constructed largely from sheet metal. As such, the most important production problems are those of sheet metal forming, and assembling. Production is here considered as not only the act of forming and assembling the required number of parts, but also the making of forming tools, and all processing of parts such as heat‐treating. Only that phase of the above concept of production which deals with the tooling for production and the forming and heat‐treating will be considered here. The design of the aircraft parts will also be discussed somewhat, for it is obvious that the design of the part (designed shape and materials used) frequently determines whether the part can or cannot be readily made.

Details

Aircraft Engineering and Aerospace Technology, vol. 15 no. 12
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 22 May 2008

Yogesh Jaluria

This paper seeks to discuss the numerical modeling of the transport processes that frequently arise in practical thermal systems and involve complexities such as property…

Abstract

Purpose

This paper seeks to discuss the numerical modeling of the transport processes that frequently arise in practical thermal systems and involve complexities such as property variations with temperature or with the shear rate in the flow, complicated regions, conjugate mechanisms, chemical reactions and combined mass transfer, and intricate boundary conditions.

Design/methodology/approach

The basic approaches that may be adopted in order to study such processes are discussed. Considerations for accurate numerical modeling are also discussed. The link between the process and the resulting product is critical in many systems such as those in manufacturing. The computational difficulties that result from the non‐Newtonian behavior of the fluid or from the strong temperature dependence of viscosity are considered in detail. Similarly, complex geometry, free surface flow, moving boundaries, combined mechanisms, and simulation of appropriate boundary conditions are important in several processes and are discussed.

Findings

Some of the important techniques to treat the problems that arise in numerical simulation are presented. Common errors that lead to inaccurate or invalid results are outlined. A few practical processes are considered in greater detail to quantify and illustrate these approaches. Validation of the numerical model is a particularly important aspect and is discussed in terms of existing results, as well as development of experimental arrangements to provide inputs for satisfactory validation.

Originality/value

Practical thermal processes involve a wide variety of complexities. The paper presents some of the important ones and discusses approaches to deal with them. The paper will be of particular value to the numerical simulation of complicated thermal processes in order to design, control or optimize them to achieve desired thermal processing.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 18 no. 3/4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 June 1953

THE greater part of this exhibition was devoted to electronic devices, many of which play a direct or indirect part in the work of the aeronautical engineer but whicharc too…

Abstract

THE greater part of this exhibition was devoted to electronic devices, many of which play a direct or indirect part in the work of the aeronautical engineer but whicharc too numerous to be fully described here. However, a number of items of special interest will be mentioned.

Details

Aircraft Engineering and Aerospace Technology, vol. 25 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 15 January 2020

Lorenzo Dall’Ava, Harry Hothi, Johann Henckel, Anna Di Laura, Sean Bergiers, Paul Shearing and Alister Hart

Three-dimensional (3D) printing is increasingly used to produce orthopaedic components for hip arthroplasty, such as acetabular cups, which show complex lattice porous structures…

Abstract

Purpose

Three-dimensional (3D) printing is increasingly used to produce orthopaedic components for hip arthroplasty, such as acetabular cups, which show complex lattice porous structures and shapes. However, limitations on the quality of the final implants are present; thus, investigations are needed to ensure adequate quality and patients safety. X-ray microcomputed tomography (micro-CT) has been recognised to be the most suitable method to evaluate the complexity of 3D-printed parts. The purpose of this study was to assess the reliability of a micro-CT analysis method comparing it with reference systems, such as coordinate measuring machine and electron microscopy.

Design/methodology/approach

3D-printed acetabular components for hip arthroplasty (n = 2) were investigated. Dimensions related to the dense and porous regions of the samples were measured. The micro-CT scanning parameters (voltage – kV, current – µA) were optimised selecting six combinations of beam voltage and current.

Findings

Micro-CT showed good correlation and agreement with both coordinate measuring machine and scanning electron microscopy when optimal scanning parameters were selected (130 kV – 100 µA to 180 kV – 80 µA). Mean discrepancies of 50 µm (± 300) and 20 µm (± 60) were found between the techniques for dense and porous dimensions. Investigation method such as micro-CT imaging may help to better understand the impact of 3D printing manufacturing technology on the properties of orthopaedic implants.

Originality/value

The optimisation of the scanning parameters and the validation of this method with reference techniques may guide further analysis of similar orthopaedic components.

Details

Rapid Prototyping Journal, vol. 26 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 20 December 2021

Xingyu Wen, Jing Zhang, Mincheol Whang and Kaixuan Liu

The purpose of this paper is to discuss the relationship between bra's visual impression and bra parts, and then to explore the application of visual impression in bra design.

Abstract

Purpose

The purpose of this paper is to discuss the relationship between bra's visual impression and bra parts, and then to explore the application of visual impression in bra design.

Design/methodology/approach

Firstly, 82 female undergraduates are asked to answered this questionnaire online, which is about the importance of parts in bra design. In the part of data analysis, the method of principal part analysis (PCA) are used to get the relationship between bra's parts, and reduce dimension of factors that influence bra design. After that, those group of features are further discussed from the perspective of visual design. Finally, design an application based on conclusion.

Findings

To get the influence features of bra appearance and improve the visual design effect, this paper matches the bra parts with visual features (color, texture, shape and space) and presents four main features of bra design: “color,” “visual texture,” “design shape” and “spatial expression” together with corresponding bra parts and technique of expression. Moreover, user interface in bra cloud customization is designed.

Practical implications

The conclusion, which shows the corresponding relationship between bra visual effect and its basic parts, has an important role in bra visual design. First, it can be useful for design idea with different technique of expression, which may supply a theoretical basis for design. Secondly, the combination of bra parts and visual features can be used to evaluate the appearance.

Originality/value

Discussing the bra visual impression based on bra's basic parts and visual features provides a theoretical method for bra design and its appearance evaluation.

Details

International Journal of Clothing Science and Technology, vol. 34 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

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