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Article
Publication date: 1 March 1983

Yoji Machida

A remarkably bullish forecast of the growth prospects for Japan's optoelectronics industry was contained in a report on the industry published earlier this year by the…

Abstract

A remarkably bullish forecast of the growth prospects for Japan's optoelectronics industry was contained in a report on the industry published earlier this year by the Economics Division of the Long Term Credit Bank of Japan. The industry was seen as growing to be as important as the electronics industry, with which it was seen as forming the mainstay of Japan's future industry. Believing it would be of interest to a wider readership we publish here a shortened version of the report.

Details

Sensor Review, vol. 3 no. 3
Type: Research Article
ISSN: 0260-2288

Article
Publication date: 22 May 2008

Alexander D. Klose and Andreas H. Hielscher

This paper sets out to give an overview about state‐of‐the‐art optical tomographic image reconstruction algorithms that are based on the equation of radiative transfer (ERT).

Abstract

Purpose

This paper sets out to give an overview about state‐of‐the‐art optical tomographic image reconstruction algorithms that are based on the equation of radiative transfer (ERT).

Design/methodology/approach

An objective function, which describes the discrepancy between measured and numerically predicted light intensity data on the tissue surface, is iteratively minimized to find the unknown spatial distribution of the optical parameters or sources. At each iteration step, the predicted partial current is calculated by a forward model for light propagation based on the ERT. The equation of radiative is solved with either finite difference or finite volume methods.

Findings

Tomographic reconstruction algorithms based on the ERT accurately recover the spatial distribution of optical tissue properties and light sources in biological tissue. These tissues either can have small geometries/large absorption coefficients, or can contain void‐like inclusions.

Originality/value

These image reconstruction methods can be employed in small animal imaging for monitoring blood oxygenation, in imaging of tumor growth, in molecular imaging of fluorescent and bioluminescent probes, in imaging of human finger joints for early diagnosis of rheumatoid arthritis, and in functional brain imaging.

Details

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

Keywords

Content available
42

Abstract

Details

Industrial Lubrication and Tribology, vol. 57 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 28 June 2011

Mohammed Omar, Konda Reddy Thotti, Rohit Parvataneni, Yi Zhou, Abed Alraoof Mayyas and Ala Qattawi

The purpose of this paper is to investigate an optical‐based scanning modality for the real‐time measurements of automotive interior gaps.

Abstract

Purpose

The purpose of this paper is to investigate an optical‐based scanning modality for the real‐time measurements of automotive interior gaps.

Design/methodology/approach

The hardware is based on a charge‐coupled device detector acquiring a laser illumination. The laser is projected on multitude of substrates with different reflectivities and surface profiles; while the scanning is progressed manually through a hand‐held setup.

Findings

The proposed software identifies the optical gap location automatically and establishes a dynamic field of view.

Research limitations/implications

The study conducts a tool reliability and repeatability study that yield an accuracy of 0.08 mm and a repeatability of less than 6.5 percent as user bias. The developed hardware/software combination, when compared with two commercial systems; a 3D scanner and an industrially packaged sensor unit used for exterior gaps, which provided repeatability values of 24 and 17 percent, respectively, with accuracies of 1.5 and 0.34 mm.

Originality/value

New hardware and software are developed in combination to operate effectively on different deco finish and gap separations.

Details

Sensor Review, vol. 31 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 June 1994

P.R. Masani

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the…

Abstract

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry that the incomplete determinism in Nature opens to the occurrence of innovation, growth, organization, teleology communication, control, contest and freedom. The new tier to the methodological edifice that cybernetics provides stands on the earlier tiers, which go back to the Ionians (c. 500 BC). However, the new insights reveal flaws in the earlier tiers, and their removal strengthens the entire edifice. The new concepts of teleological activity and contest allow the clear demarcation of the military sciences as those whose subject matter is teleological activity involving contest. The paramount question “what ought to be done”, outside the empirical realm, is embraced by the scientific methodology. It also embraces the cognitive sciences that ask how the human mind is able to discover, and how the sequence of discoveries might converge to a true description of reality.

Details

Kybernetes, vol. 23 no. 4
Type: Research Article
ISSN: 0368-492X

Keywords

Content available
Article
Publication date: 1 September 2006

49

Abstract

Details

Microelectronics International, vol. 23 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Abstract

Details

Silicon Valley North
Type: Book
ISBN: 978-0-08044-457-4

Article
Publication date: 1 March 1994

Gary Graham and Brian Kenny

The proper matching of industry structure to strategy is expected to have a positive impact upon organisational performance. This relationship has not been fully examined…

Abstract

The proper matching of industry structure to strategy is expected to have a positive impact upon organisational performance. This relationship has not been fully examined in the defence industry. The central aim of this paper is to link the competitive performance of small, high technology defence firms to their ability to adapt to industry structure changes. With this in mind a study was conducted to extend Porter's (1980) framework of the strategic management of industry structural change. The study draws upon the experiences of 40 small, high technology defence firms in the UK. Firms in the sample range from 5 to 200 employees, and £50,000 to £10m sales turnover. The study broadens the findings of exploratory research undertaken in the buying department of two large defence firms. A questionnaire was designed to identify macro level phenomena and detail hypotheses generated by the case studies. The empirical analysis of the creation and sustaining of competitive advantages will focus on strategic determinants, and inter‐organisational variables that influence the performance of small firms in tendering for defence sub‐contracts.

Details

Journal of Small Business and Enterprise Development, vol. 1 no. 3
Type: Research Article
ISSN: 1462-6004

Article
Publication date: 3 February 2021

Xinjie Zhang, Fansen Kong, Zhiyuan Gu and Xiao Shen

FOV splicing optical remote sensing instruments have a strict requirement for the focal length consistency of the lens. In conventional optical-mechanical structure…

Abstract

Purpose

FOV splicing optical remote sensing instruments have a strict requirement for the focal length consistency of the lens. In conventional optical-mechanical structure design, each optical element is equally distributed with high accuracy and everyone must have a high machining and assembly accuracy. For optical remote sensors with a large number of optical elements, this design brings great difficulties to lens manufacture and alignment.

Design/methodology/approach

Taking the relay lens in an optical remote sensing instrument with the field of view splicing as an example, errors of the system are redistributed to optical elements. Two optical elements, which have the greatest influence on modulation transfer function (MTF) of the system are mounted with high accuracy centering and the other elements are fixed by gland ring with common machining accuracy. The reduction ratio consistency difference among lenses is compensated by adjusting the optical spacing between the two elements.

Findings

Based on optical system simulation analysis, the optimized structure can compensate for the difference of reduction ratio among lens by grinding the washer thickness in the range of ±0.37 mm. The test data for the image quality of the lens show that the MTF value declined 0.043 within ±0.4 mm of space change between two barrels. The results indicate that the reduction ratio can be corrected by adjusting the washer thickness and the image quality will not obviously decline.

Originality/value

This paper confirms that this work is original and has not been published elsewhere nor is it currently under consideration for publication elsewhere. In this paper, the optimum structural design of the reduction relay lens for the field of view stitching applications is reported. The method of adjusting washer thickness is applied to compensate for the reduction ratio consistency difference of lenses. The optimized structure also greatly reduces the difficulty of lenses manufacture, alignment and improves the efficiency of assembly.

Details

Sensor Review, vol. 41 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 14 February 2022

Kai Xiong, Chunling Wei and Peng Zhou

This paper aims to improve the performance of the autonomous optical navigation using relativistic perturbation of starlight, which is a promising technique for future…

Abstract

Purpose

This paper aims to improve the performance of the autonomous optical navigation using relativistic perturbation of starlight, which is a promising technique for future space missions. Through measuring the change in inter-star angle due to the stellar aberration and the gravitational deflection of light with space-based optical instruments, the position and velocity vectors of the spacecraft can be estimated iteratively.

Design/methodology/approach

To enhance the navigation performance, an integrated optical navigation (ION) method based on the fusion of both the inter-star angle and the inter-satellite line-of-sight measurements is presented. A Q-learning extended Kalman filter (QLEKF) is designed to optimize the state estimate.

Findings

Simulations illustrate that the integrated optical navigation outperforms the existing method using only inter-star angle measurement. Moreover, the QLEKF is superior to the traditional extended Kalman filter in navigation accuracy.

Originality/value

A novel ION method is presented, and an effective QLEKF algorithm is designed for information fusion.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

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