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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 design, each…

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: 8 June 2015

Rithin Kumar N.B., Vincent Crasta and B M Praveen

The purpose of this paper is to explore the synthesis, preparation and investigation of micro structural, optical and mechanical studies of polyvinyl alcohol (PVA) doped with…

Abstract

Purpose

The purpose of this paper is to explore the synthesis, preparation and investigation of micro structural, optical and mechanical studies of polyvinyl alcohol (PVA) doped with tungsten oxide (WO3) nanocomposites films. These films were prepared by simple solvent casting method is further characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-visible spectroscopy, universal testing machine (UTM), scanning electron microscope (SEM), energy-dispersive analysis of X-rays (EDAX) and atomic force microscope (AFM) techniques to determine the enhancement in structural, optical and mechanical properties with increase in dopant concentration.

Design/methodology/approach

The present paper deals with the synthesis of WO3 nanoparticles using precipitation method and doping into PVA matrix to prepare a polymer nanocomposite film using coagulation and solvent casting method. The FTIR explores the interaction of dopants with PVA matrix. The XRD spectra investigate the variation of crystallinity. The UV/Vis-spectra reveals the information of optical energy band gap and the Urbach Energy for different doping concentrations. The mechanical properties of the nanocomposites were exposed using UTM. The phase homogeneity, film topography, chemical composition of nanocomposites is analyzed using SEM, EDAX and AFM techniques supporting the above results.

Findings

The films characterized by FTIR spectroscopy explores the irregular shift in the bands of pure and doped PVA can be understood on the basis of intra/inter molecular hydrogen bonding with the adjacent OH group of PVA backbone. The XRD result reconnoiters that the particle size and crystallinity increases whereas microstructural strain and dislocation density decreases with increase in dopant concentration. Further the drastic decrease in optical energy band gap E g =0.94 eV for doping concentration x=15 wt% and the increase in values of Urbach Energy (E u ) with doping concentrations were investigated by UV/Vis spectra. Also the extinction coefficient was high in the wavelength range of 250-400 nm and low in the wavelength range of 400-1,200 nm. The mechanical studies indicates that the addition of the WO3 with weight percentage concentration x=15 percent increases the tensile strength and Young’s modulus. The phase homogeneity, the particle size of the dopants and chemical composition of nanocomposites is analyzed using SEM and EDAX. The film topography of the nanocomposites is analyzed using AFM techniques supporting the above results.

Originality/value

The investigation of synthesis, preparation and investigation of micro structural, optical and mechanical studies of PVA doped with WO3 nanocomposites films as been done. The results prove that these nanocomposites having good mechanical strength with crystalline nature and also very low optical energy gap value that could find possible applications in industries.

Details

International Journal of Structural Integrity, vol. 6 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 April 2022

Prashil Desai and R.N. Jagtap

There is a rising demand for high-performance 3D printed objects that have established potential applications in the sector of dental, automotive, electronics, aerospace, etc…

152

Abstract

Purpose

There is a rising demand for high-performance 3D printed objects that have established potential applications in the sector of dental, automotive, electronics, aerospace, etc. Thus, to meet the requirements of high-performance 3D printed objects, this study has synthesized, formulated and applied a resorcinol epoxy acrylate (REA) oligomer to a stereolithography (SLA) 3D printer.

Design/methodology/approach

Different formulations were developed by blending reactive diluents in the concentration of 10%, 15% and 20%, along with the fixed quantity of photo-initiators in the REA oligomer. The structure of synthesized REA oligomer was confirmed using 13 C nuclear magnetic resonance (NMR) and 1H NMR spectroscopy, and the rheological properties for prepared REA formulations were also evaluated. The ultraviolet (UV)-cured specimens of all REA formulations were thoroughly examined based on physical, chemical, optical, mechanical and thermal properties. The best suitable formulation was selected for SLA 3D printing.

Findings

As perceived, UV cured REA specimens exhibit superior mechanical, chemical and thermal properties, portraying the ability to use as a high-performance material. The increase in the concentration of reactive diluents indicated a significant improvement in the properties of REA resin. The 20% diluted formulation achieved excellent compatibility with a SLA 3D printer; thus, 3D objects are cast with good dimensional stability and printability.

Originality/value

Resorcinol-based resins have always been a key additive used to enhance properties in the coating and tire industry. In a new attempt UV, curable REA has been applied to a SLA 3D printer to cast high-performance 3D printed objects.

Details

Pigment & Resin Technology, vol. 52 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 9 January 2019

Nikita Mhadeshwar, Kunal Wazarkar and Anagha S. Sabnis

This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated to study…

Abstract

Purpose

This paper aims to prepare acrylic functional ricinoleic acid monomer and incorporate it in conventional miniemulsion polymerization. Subsequently, paints were formulated to study the variation in final coating properties.

Design/methodology/approach

Synthesis process involved the esterification of ricinoleic acid with 2-hydroxy methyl methacrylate in the presence of FASCAT-4100 catalyst. The final product of the reaction, methacrylated ricinoleic acid (MRA), was confirmed using Fourier-transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy and determining acid and iodine value. Further, MRA was incorporated in various concentrations (1, 2 and 3 Wt.%) along with methyl acrylate and butyl acrylate in conventional miniemulsion polymerization and paints were formulated thereof.

Findings

It was observed that with the addition of MRA monomer, flexibility of emulsion films increased as indicated by glass transition temperature and elongation value (percentage). Moreover, with the addition of MRA monomer, improvement in mechanical and chemical properties of the coatings was observed.

Research limitations/implications

Even a low concentration MRA monomer (as low as 3 per cent) caused a significant reduction in the glass transition temperature of emulsion films. Thus, it can be efficiently used in applications such as adhesives and elastomeric coatings.

Originality/value

The acrylic functional monomer derived from ricinoleic acid is unique and not yet incorporated in miniemulsion polymerization. The synthesized monomer can be used in coatings where low Tg emulsions are required.

Article
Publication date: 1 November 1985

Souriau, has recently obtained Q.P.L. (Qualified Products List) approval for two of its range of circular connectors.

Abstract

Souriau, has recently obtained Q.P.L. (Qualified Products List) approval for two of its range of circular connectors.

Details

Aircraft Engineering and Aerospace Technology, vol. 57 no. 11
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 5 April 2011

Chih‐Peng Chu, Ci‐Rong Li and Chen‐Ju Lin

The purpose of this paper is to further understand the joint effect of project‐level exploratory and exploitative learning in new product development. It aims to examine the…

1572

Abstract

Purpose

The purpose of this paper is to further understand the joint effect of project‐level exploratory and exploitative learning in new product development. It aims to examine the complicated relationships among exploratory learning, exploitative learning and new product performance at a single project level. In addition, it seeks to shed light on the contextual effects of a firm's market orientation on the relationship between joint occurrence of both learning activities and new product development performance.

Design/methodology/approach

The paper is based on a questionnaire survey/analysis of a sample of 298 projects from high‐tech firms in Taiwan.

Findings

The findings suggest that the joint occurrence of both learning activities has a positive effect on new product performance and depends upon a high level of one learning activity coupled with a small dose of the other. Drawing on cultural and behavioral perspectives of market orientation, the results also indicate that market orientation may enhance the joint effect of both learning activities on new product performance.

Practical implications

This paper offers insight to project managers with regard to the importance of rationally mixing with exploratory and exploitative learning during new product development. Furthermore, the study argues that market orientation is an alternative of organizational design that fosters the positive joint effect of both learning behaviors.

Originality/value

The results empirically support the theoretical argument that a high‐low matching of exploratory and exploitative learning can enhance performance at the level of a single project. The study provides a multiple‐level framework to understand how the firm‐level MO strengthens the positive effects of joint occurrence of project‐level exploratory and exploitative learning activities during new product development.

Details

European Journal of Marketing, vol. 45 no. 4
Type: Research Article
ISSN: 0309-0566

Keywords

Article
Publication date: 1 December 2002

George K. Stylios

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the…

Abstract

Looks at the eighth published year of the ITCRR and the research, from far and near, involved in this. Muses on the fact that, though all the usual processes are to the fore, the downside part of the industry is garment making which is the least developed side. Posits that the manufacture of clothing needs to become more technologically advanced as does retailing. Closes by emphasising support for the community in all its efforts.

Details

International Journal of Clothing Science and Technology, vol. 14 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 2001

George Stylios

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within…

1078

Abstract

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within the newer research areas under the microscope of the community involved, technical textiles focuses on new, ‘smart’ garments and the initiatives in this field in both the UK and the international community at large. Covers this subject at length.

Details

International Journal of Clothing Science and Technology, vol. 13 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 13 July 2023

Abdul Lateef, Zulfiqar Ali Raza, Muhammad Aslam, Muhammad Shoaib Ur Rehman, Asma Iftikhar and Abdul Zahir

This study aims to fabricate multiwalled carbon nanotubes (MWCNTs)-mediated polyvinyl alcohol (PVA) composite films using the solution casting approach.

Abstract

Purpose

This study aims to fabricate multiwalled carbon nanotubes (MWCNTs)-mediated polyvinyl alcohol (PVA) composite films using the solution casting approach.

Design/methodology/approach

The prepared films were evaluated for diverse structural, surface, optical and electrical attributes using advanced analytical techniques, i.e. electron microscopy for surface morphology, Fourier transform infrared spectroscopy for tracing chemical functionalities, x-ray diffraction (XRD) for crystal patterns, water contact angle (WCA) analysis for surface wettability and UV visible spectroscopy for optical absorption parameters. The specimens were also investigated for certain rheological, mechanical and electrical properties, where applicable.

Findings

The surface morphology results expressed a better dispersion of MWCNTs in the resultant PVA-based nanocomposite film. The XRD analysis exhibited that the nanocomposite film was crystalline. The surface wettability analysis indicated that with the inclusion of MWCNTs, the WCA of the resultant nanocomposite film improved to 89.4° from 44° with the pristine PVA film. The MWCNTs (1.00%, w/w) incorporated PVA-based film exhibited a tensile strength of 54.0 MPa as compared to that of native PVA as 25.3 MPa film. There observed a decreased bandgap (from 5.25 to 5.14 eV) on incorporating the MWCNTs in the PVA-based nanocomposite film.

Practical implications

The MWCNTs’ inclusion in the PVA matrix could enhance the AC conductivity of the resultant nanocomposite film. The prepared nanocomposite film might be useful in designing certain optoelectronic devices.

Originality/value

The results demonstrated the successful MWCNTs mediation in the PVA-based composite films expressed good intercalation of the precursors; this resulted in decreased bandgap, usually, desirable for optoelectronic applications.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 August 1987

THE System for Positioning and Automated Co‐ordinate Evaluation (SPACE) is a completely new development for industrial measurement in real time. Designed by Kern and available in…

Abstract

THE System for Positioning and Automated Co‐ordinate Evaluation (SPACE) is a completely new development for industrial measurement in real time. Designed by Kern and available in the UK from the Optical and Mechanical Development Company (OMD), SPACE is based on Kern's concept of the Electronic Co‐ordinate Determination System (ECDS). By means of between two to eight high precision, 0.3 second electronic theodolites, angular data on the location of points on an object may be obtained by triangulation and reduced using sophisticated software into three‐dimensional co‐ordinates.

Details

Aircraft Engineering and Aerospace Technology, vol. 59 no. 8
Type: Research Article
ISSN: 0002-2667

1 – 10 of 36