Surface plasmons (SPs) are coherent oscillations of conduction electrons on a metal surface excited by electromagnetic radiation at a metal -dielectric interface. The growing field of research on such light -metal interactions is known as ‘plasmonics’. 1-3 This branch of research has attracted much attention due to its potential applications in miniaturized optical devices, sensors, and photonic circuits as well as in medical diagnostics and therapeutics. 4-8

Nanostructured plasmonic sensors.

The objective of this study is to review and evaluate the applications of magnesium in the automotive industry that can significantly contribute to greater fuel economy and environmental conservation. In the study, the current advantages, limitations, technological barriers and future prospects of Mg alloys in the automotive industry are given. The usage of magnesium in automotive applications is also assessed for the impact on environmental conservation. Recent developments in coating and alloying of Mg improved the creep and corrosion resistance properties of magnesium alloys for elevated temperature and corrosive environments. The results of the study conclude that reasonable prices and improved properties of Mg and its alloys will lead to massive use of magnesium. Compared to using alternative materials, using Mg alloys results in a 22% to 70% weight reduction. Lastly, the use of magnesium in automotive components is increasing as knowledge of forming processes of Mg alloys increases.

Magnesium and its alloys applications in automotive industry

Applied Numerical Analysis. By C.F. Gerald. Pp. xii, 340. £3·60. 1970. (Addison-Wesley.)

In-service structural health monitoring (SHM) of engineering structures has assumed a significant role in assessing their safety and integrity. Fibre Bragg grating (FBG) sensors have emerged as a reliable, in situ, non-destructive tool for monitoring, diagnostics and control in civil structures. The versatility of FBG sensors represents a key advantage over other technologies in the structural sensing field. In this article, the recent research and development activities in structural health monitoring using FBG sensors have been critically reviewed, highlighting the areas where further work is needed. A few packaging schemes for FBG strain sensors are also discussed. Finally a few limitations and market barriers associated with the use of these sensors have been addressed.

Fibre Bragg gratings in structural health monitoring—Present status and applications

Application of response surface methodology in describing the performance of coated carbide tools when turning AISI 1045 steel

Dry machining: Machining of the future

Brittle–ductile transition in the diamond cutting of glasses with the aid of ultrasonic vibration

This paper describes an efficient method of packing boxes into a container using a unique spatial representation technique. Unlike other algorithms, the packing algorithm in this paper is not constrained by the physical packing sequence, that is, back to front, or bottom to top. This extra flexibility allows the program to pack the boxes more efficiently. The packing plan can be generated to suit the actual packing sequence. The program is implemented on an IBM PC and a comparison has been made with a similar software. The results, in terms of packing efficiency and packing time, are promising.

Applying spatial representation techniques to the container packing problem

A method and apparatus for precision laser scanning suitable for precision machining or cleaning using an ultrashort pulsed laser beam are disclosed. The apparatus employs a laser source that emits a pulsed laser beam, a dispersion compensation scanner that scans the pulsed laser beam, and a focusing unit that focuses the pulsed laser beam from the dispersion compensation scanner on a work piece. The dispersion compensation scanner comprises a first scanning device that scans the pulsed laser beam in a first direction and that causes dispersion of the pulsed laser beam. The dispersion compensation scanner further comprises a first dispersion compensation device that compensates for the dispersion caused by the first scanning device. Effects of polarization of the ultrashort pulsed laser beam on the quality of machining are described. Uses of the invention in direct fabrication of photolithographic masks and in work piece cleaning are also described.

Ultrashort pulsed laser micromachining/submicromachining using an acoustooptic scanning device with dispersion compensation

A technique and apparatus is disclosed for micro machining using an ultra short laser pulse in the range of femto second pulsing. The system is also applicable for smaller or higher pulse rates depending upon the application. The system includes methods for improving the beam quality of the laser beam by filtering. Moreover, it includes the concept of scanning the laser beam using acousto optic deflectors in the X-Y direction rather than conventional mechanical movement of the work piece or deflecting the beam using a mirror. The technique also incorporates means for modulating the ultra short laser pulse in order to control the number of pulses of the ultra short laser pulse which will strike the target surface at each of the target points by a combination of acousto optic modulators. The concept of applying elliptical or circular laser beam spots for machining rather than a circular one is also disclosed.

Bryan Kok Ann Ngoi

Papers

Dry machining: Machining of the future

Brittle–ductile transition in the diamond cutting of glasses with the aid of ultrasonic vibration

Applying spatial representation techniques to the container packing problem

Ultrashort pulsed laser micromachining/submicromachining using an acoustooptic scanning device with dispersion compensation

Three dimensional micro machining with a modulated ultra-short laser pulse