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Article
Publication date: 1 September 2000

Robert Lange and Peter Seitz

The world’s first time‐of‐flight (TOF) 3D range camera without moving parts, based on a custom solid‐state imaging device is described in this article. With the single exception…

1499

Abstract

The world’s first time‐of‐flight (TOF) 3D range camera without moving parts, based on a custom solid‐state imaging device is described in this article. With the single exception of the smart‐pixel array, only electronic and optical standard components are used. The range camera does not need any mechanically scanning parts. It acquires 10 range images per second and achieves a resolution of a few centimeters over a distance range of 10‐20 meters for non‐cooperative targets. The illumination source consists of 160 LEDs, modulated at 20MHz, with a total optical power of about 800mW. The description of the smart pixel’s working principle and the presentation of our first 3D measurements are completed with a discussion of the theoretical limitations and a comparison with the system performance.

Details

Sensor Review, vol. 20 no. 3
Type: Research Article
ISSN: 0260-2288

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Available. Content available
Book part
Publication date: 2 February 2000

Abstract

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Panel Data and Structural Labour Market Models
Type: Book
ISBN: 978-0-44450-319-0

Available. Content available

Abstract

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Sensor Review, vol. 22 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 1 April 1990

Don Braggins

New visual inspection techniques overcome the Nyquist limit to provide high precision measurement of component positions.

84

Abstract

New visual inspection techniques overcome the Nyquist limit to provide high precision measurement of component positions.

Details

Sensor Review, vol. 10 no. 4
Type: Research Article
ISSN: 0260-2288

Available. Open Access. Open Access
Article
Publication date: 22 March 2021

Mariusz Kowalski, Zdobyslaw Jan Goraj and Bartłomiej Goliszek

The purpose of this paper is to present the result of calculations that were performed to estimate the structural weight of the passenger aircraft using novel technological…

1900

Abstract

Purpose

The purpose of this paper is to present the result of calculations that were performed to estimate the structural weight of the passenger aircraft using novel technological solution. Mass penalty resulting from the installation of the fuselage boundary layer ingestion device was needed in the CENTRELINE project to be able to estimate the real benefits of the applied technology.

Design/methodology/approach

This paper focusses on the finite element analysis (FEA) of the fuselage and wing primary load-carrying structures. Masses obtained in these analyses were used as an input for the total structural mass calculation based on semi-empirical equations.

Findings

Combining FEA with semi-empirical equations makes it possible to estimate the mass of structures at an early technology readiness level and gives the possibility of obtaining more accurate results than those obtained using only empirical formulas. The applied methodology allows estimating the mass in case of using unusual structural solutions, which are not covered by formulas available in the literature.

Practical implications

Accurate structural mass estimation is possible at an earlier design stage of the project based on the presented methodology, which allows for easier and less costly changes in designed aircrafts.

Originality/value

The presented methodology is an original method of mass estimation based on a two-track approach. The analytical formulas available in the literature have worked well for aeroplanes of conventional design, but thanks to the connection with FEA presented in this paper, it is possible to estimate the structure mass of aeroplanes using unconventional technological solutions.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 9
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 25 January 2019

Zdobyslaw Jan Goraj, Mariusz Kowalski and Bartlomiej Goliszek

This paper aims to present the results of calculations that checked how the longerons and frames arrangement affects the stiffness of a conventional structure. The paper focuses…

282

Abstract

Purpose

This paper aims to present the results of calculations that checked how the longerons and frames arrangement affects the stiffness of a conventional structure. The paper focuses only on first stage of research – analysis of small displacement. Main goal was to compare different structures under static loads. These results are also compared with the results obtained for a geodetic structure fuselage model of the same dimensions subjected to the same internal and external loads.

Design/methodology/approach

The finite element method analysis was carried out for a section of the fuselage with a diameter of 6.3 m and a length equal to 10 m. A conventional and lattice structure – known as geodetic – was used.

Findings

Finite element analyses of the fuselage model with conventional and geodetic structures showed that with comparable stiffness, the weight of the geodetic fuselage is almost 20 per cent lower than that of the conventional one.

Research limitations/implications

This analysis is limited to small displacements, as the linear version of finite element method was used. Research and articles planned for the future will focus on nonlinear finite element method (FEM) analysis such as buckling, structure stability and limit cycles.

Practical implications

The increasing maturity of composite structures manufacturing technology offers great opportunities for aircraft designers. The use of carbon fibers with advanced resin systems and application of the geodetic fuselage concept gives the opportunity to obtain advanced structures with excellent mechanical properties and low weight.

Originality/value

This paper presents very efficient method of assessing and comparison of the stiffness and weight of geodetic and conventional fuselage structure. Geodetic fuselage design in combination with advanced composite materials yields an additional fuselage weight reduction of approximately 10 per cent. The additional weight reduction is achieved by reducing the number of rivets needed for joining the elements. A fuselage with a geodetic structure compared to the classic fuselage with the same outer diameter has a larger inner diameter, which gives a larger usable space in the cabin. The approach applied in this paper consisting in analyzing of main parameters of geodetic structure (hoop ribs, helical ribs and angle between the helical ribs) on fuselage stiffness and weight is original.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 6
Type: Research Article
ISSN: 1748-8842

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Book part
Publication date: 13 December 2013

Eugene Choo and Shannon Seitz

We develop and estimate an empirical collective model with endogenous marriage formation, participation, and family labor supply. Intra-household transfers arise endogenously as…

Abstract

We develop and estimate an empirical collective model with endogenous marriage formation, participation, and family labor supply. Intra-household transfers arise endogenously as the transfers that clear the marriage market. The intra-household allocation can be recovered from observations on marriage decisions. Introducing the marriage market in the collective model allows us to independently estimate transfers from labor supplies and from marriage decisions. We estimate a semiparametric version of our model using 1980, 1990, and 2000 US Census data. Estimates of the model using marriage data are much more consistent with the theoretical predictions than estimates derived from labor supply.

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Structural Econometric Models
Type: Book
ISBN: 978-1-78350-052-9

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Article
Publication date: 1 April 1990

Anne E. Zald and Cathy Seitz Whitaker

Despite the title of this bibliography, there was not a truly underground press in the United States during the 1960s and 1970s. The phrase is amisnomer, reputedly coined on the…

164

Abstract

Despite the title of this bibliography, there was not a truly underground press in the United States during the 1960s and 1970s. The phrase is amisnomer, reputedly coined on the spur of the moment in 1966 by Thomas Forcade when asked to describe the newly established news service, Underground Press Syndicate, of which he was an active member. The papers mentioned in this bibliography, except for the publications of the Weather Underground, were not published by secretive, covert organizations. Freedom of the press and of expression is protected by the First Amendment to the Constitution, although often only symbolically as the experience of the undergrounds will show, and most of the publications that fall into the “underground” described herein maintained public offices, contracted with commercial printers, and often used the U.S. Postal Service to distribute their publications.

Details

Reference Services Review, vol. 18 no. 4
Type: Research Article
ISSN: 0090-7324

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Article
Publication date: 1 September 2005

Peter Wells and Margarete Seitz

To delineate typologies that capture the relationship between closed‐loop supply chains and value‐added business models, and thereby to suggest a research agenda for the…

7682

Abstract

Purpose

To delineate typologies that capture the relationship between closed‐loop supply chains and value‐added business models, and thereby to suggest a research agenda for the transition to sustainable business.

Design/methodology/approach

Develops four new theoretical categories or typologies of closed‐loop systems and applies them to the context of the automotive industry. Conceptual, rather than empirical.

Findings

That hybrid closed‐loop systems can be combined with innovative non‐linear value configurations to enable the transition to more sustainable production and consumption.

Research limitations/implications

Identifies research agenda to explore how novel business models can integrate with various closed‐loop systems. Theoretical, but grounded in research into the automotive industry.

Practical implications

That closed‐loop systems are best implemented outside traditional linear value added structures.

Originality/value

Places closed‐loop systems at the heart of the (redesigned) business model rather than as an accessory that must be adapted to the demands of existing approaches. Suggests scholars should be part of this innovative process, not merely observers.

Details

Supply Chain Management: An International Journal, vol. 10 no. 4
Type: Research Article
ISSN: 1359-8546

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Book part
Publication date: 7 November 2022

Kaylar Recker

It should come as no surprise that Americans believe corruption dominates the US political system and, in particular, that members of Congress are in the pockets of wealthy…

Abstract

It should come as no surprise that Americans believe corruption dominates the US political system and, in particular, that members of Congress are in the pockets of wealthy special interests and do not represent the people's views. Among other things, this has led to a gradual decrease in public confidence in government, trust in political institutions, and demands for anti-corruption reforms. Yet, calls for congressional reform are not new. What is unusual is the degree to which the political institutions, particularly Congress, have become unpopular; the extent American's believe the system is out of balance; and the people's distaste for democracy. As public perceptions of political corruption deepen, how is Congress responding to these concerns? Recent events indicate genuine attempts to solve, or at least reduce, the appearance of government corruption. For example, in the 2018 midterm elections, many political candidates signaled a willingness to address the public's grievances. In fact, the newly elected House of Representatives created and introduced legislation that addressed sweeping congressional corruption. This chapter aims to identify and trace congressional reform attempts such as banning lobbyists from fundraising, restrictions on the revolving door for politicians and job hunting disclosures, and other structural solutions considered important to prevent corruption. In particular, the author uses a historical lens to uncover and assess past and current attempts to fix congressional corruption.

Details

Scandal and Corruption in Congress
Type: Book
ISBN: 978-1-80117-120-5

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