Sustainable packaging design: a holistic methodology for packaging design

This study describes a holistic methodology for sustainable packaging design. This methodology studies the combined systems of packaging and the packaged products across the whole distribution chain from manufacturer to end consumer and the life cycle from raw material extraction to the waste phase. It contains a number of indicators that are grouped into the following main categories: environmental sustainability, distribution costs, product protection, market acceptance and user friendliness. The methodology integrates a number of different analytical methods. It is intended to be used in packaging design and optimisation, for idea generation, decision support and as documentation of properties of existing packaging systems. The study describes experiences with the methodology from one case study in the Norwegian Food Industry. The experiences show that the methodology is very comprehensive, and gives a good overview of the properties of a packaging solution. It enables quantitative comparisons between different packaging solutions throughout the design process. The methodology reduces the risk of implementing sub‐optimal packaging solutions. An additional benefit of the methodology is gained by working in cross‐functional teams. One potential drawback is that the methodology can be resource and data intensive. The methodology can be used as a tool box in packaging design, i.e. it is not necessary to use all methods and quantify all indicators to gain benefit. However, all indicators and requirements should be evaluated and considered. In all cases, it should be considered to include additional indicators if important sustainability issues have not been addressed. Copyright © 2010 John Wiley & Sons, Ltd.     

Static random-access memory based on self-aligned-gate (Al,Ga)As/n+-GaAs superlattice modulation-doped FETs

A 64 bit, fully decoded static random-access memory (SRAM) has been fabricated utilising self-aligned-gate (Al,Ga)As/n+-GaAs superlattice modulation-doped FETs (MODFETs) for the first time. Read access times of 1.1 ns at 270 ?W/bit and minimum write-enable pulse widths less than 2 ns were demonstrated at room temperature. Typical room-temperature extrinsic transconductances and output conductances of 240 mS/mm and 7 mS/mm, respectively, were observed for the superlattice MODFET devices.     

A self-aligned gate III-V heterostructure FET process forultrahigh-speed digital and mixed analog/digital LSI/VLSI circuits

A planar ion-implanted self-aligned gate process for the fabrication of high-speed digital and mixed analog/digital LSI/VLSI integrated circuits is reported. A 4-b analog-to-digital converter, a 2500-gate 8×8 multiplier/accumulator, and a 4500-gate 16×16 complex multiplier have been demonstrated using enhancement-mode n⁺ -(Al,Ga)As/MODFETs, superlattice MODFETs, and doped channel heterostructure field-effect transistors (FETs) whose epitaxial layers were grown by molecular-beam epitaxy. With nominal 1-μm gate-length devices, direct-coupled FET logic ring oscillators with realistic circuit structures have propagation delays of 30 ps/stage at a power dissipation of 1.2 mW/stage. In LSI circuit operation, these gates have delays of 89 ps/gate at a power dissipation of 1.38 mW/gate when loaded with an average fan-out of 2.5 gates and about 1000 μm of high-density interconnects. High-performance voltage comparator circuits operated at sampling rates greater than 2.5 GHz at Nyquist analog input rates and with static hysteresis of less than 1 mV at room temperature. Fully functional 4-b analog-to-digital circuits operating at frequencies up to 2 GHz were obtained     

Applications of power series in computational geometry

A number of algorithms are presented for obtaining power series expansions of curves and surfaces at a point. Some results on the radius of convergence are given. Two applications of series are given:

1. • for curve tracing algorithms, where a truncated series is used to approximate the curve of intersection of two surfaces

2. • to define nth degree geometric continuity, for arbitrary

Frictionally excited thermoelastic instability in disc brakes—Transient problem in the full contact regime

Exceeding the critical sliding velocity in disc brakes can cause unwanted forming of hot spots, non-uniform distribution of contact pressure, vibration, and also, in many cases, permanent damage of the disc. Consequently, in the last decade, a great deal of consideration has been given to modeling methods of thermoelastic instability (TEI), which leads to these effects. Models based on the finite element method are also being developed in addition to the analytical approach.The analytical model of TEI development described in the paper by Lee and Barber [Frictionally excited thermoelastic instability in automotive disk brakes. ASME Journal of Tribology 1993;115:607-14] has been expanded in the presented work. Specific attention was given to the modification of their model, to catch the fact that the arc length of pads is less than the circumference of the disc, and to the development of temperature perturbation amplitude in the early stage of breaking, when pads are in the full contact with the disc. A way is proposed how to take into account both of the initial non-flatness of the disc friction surface and change of the perturbation shape inside the disc in the course of braking.     

Ohmic contacts to semiconducting diamond using a Ti/Pt/Au trilayer metallization scheme

Ohmic contacts have been fabricated on a naturally occurring type IIb diamond crystal using an annealed Ti/Pt/Au trilayer metallization where the Pt served successfully as a barrier to Ti diffusion into the Au capping layer. However, a specific contact resistance could not be reliably determined using transmission line model measurements. Auger microanalysis revealed the presence of Ti on the diamond surface near the ohmic contact pads. The most likely origin of the Ti on the diamond surface was determined to be lateral diffusion from beneath the contact pads. This would have produced a nonuniform concentration of Ti across the diamond surface which, in turn, would have affected the diamond sheet resistance in a complicated way.     

Modern Spin Relaxation Techniques for Liquid Crystals: Nuclear Spin Probes in Thermotropic Mesophases

The existence of well-resolved dipolar and/or quadrupolar splittings in the NMR spectra of solutes in ordered phases greatly facilitates analysis of nulcear spin relaxation pathways in terms of individual spectral density parameters evaluated at well-defined frequencies. Both auto- and cross-correlation terms are experimentally accessible via an appropriate combination of modern pulse techniques, and this detailed information is of use in assessing the validity of various models for molecular motion in ordered systems. Spectral density data for small, rigid solutes in nematic mesophases can be rationalized in terms of rotational diffusion, including effects of static order, together with order director fluctuations. The techniques developed for the simpler nematics can readily be used for solutes in the smectic phase as well as for studies of the liquid crystalline solvent molecules themselves.     

Impact of polarisation mode dispersion on 10 Gbit/s terrestrialsystems over non-dispersion-shifted fibre

Depending on the launched state of polarisation 10 Gbit/s system impairments are investigated experimentally in the presence of chromatic dispersion and variable differential group delay caused by polarisation mode dispersion. In addition an actual fibre cable, not an optical simulator was used to bring polarisation mode dispersion     

Cholecystostomy

The role of cholecystostomy in the sugical treatment of gallstones has been considered. In a consecutive series of 558 patients who underwent surgery for gallstones, 30 (5-4 per cent) had cholecystostomy alone and a further 17 (3-1 per cent) cholecystostomy combined with exploration of the bile ducts. Cholecystostomy was done because cholecystectomy was technically very hazardous in 15 patients. In the remaining patients cholecystostomy was preferred to cholecystectomy because o f the poor general condition of the patient or the presence of pancreatitis. Of the 47 patients submitted to cholecystostomy, 2(4-2 per cent) died postoeratively and 4(8-4 percent) subsequently underwent cholecystectomy. Of 24 patients who were available for long term follow-up, only 1 patient had pain which was definitely considered to be due to gallstones, although 3 other patients also had abdominal pain, while 7 patients showed radiological evidience of gallstones. It is contended that cholecystostomy has a small but definite part to play in the immediate surgical treatment of gallstones and that the long term results of the operation are sufficiently good to justify its use in selected patients.