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The purpose of this paper is to present a numerical analysis of the laser surgery of port wine stain (PWS) with cryogen spray cooling to compare the treatment effect between pulse dye laser and Nd:YAG laser, explain the incomplete clear of the lesion and optimize the laser parameter.

The complex structure of skin and PWS is simplified to a multi-layer skin model that consists of top epidermal layer and underneath dermis layer embedded with discrete blood vessels. The cooling effect of cryogen spray before laser firing is quantified by a general correlation obtained recently from the experimental data. The light distribution is modeled by the Monte Carlo method. The heat transfer in skin tissue is calculated by Pennes bioheat transfer model. The thermal damage of blood vessel is quantified by the Arrhenius damage integral.

For the vessel size studied (10-120 µm), pulse duration is recommended shorter than 6 ms. Large and deeply buried vessels, which may survive from 595 nm laser irradiation, can be coagulated by 1,064 nm laser due to its deep light penetration depth in skin. Furthermore, a desired uniform heating within the large vessel lumen can be achieved by 1,064 nm laser whereas 595 nm laser produce non-uniform heating.

The possible reason for the poor responding and incomplete clearance lesions is clarified. Laser wavelength and pulse duration are suggested to improve the clinical results.

This paper aims to describe and investigate the mathematical models and numerical modeling of how a cell membrane is affected by a transient ice freezing front combined with the influence of thermal fluctuations and anisotropy.

The study consists of mathematical modeling, validation with an analytical solution, and shows the influence of thermal noises on phase front dynamics and how it influences the freezing process of a single red blood cell. The numerical calculation has been modeled in the framework of the phase field method with a Cahn–Hilliard formulation of a free energy functional.

The results show an influence scale on directional phase front propagation dynamics and how significant are stochastic thermal noises in micro-scale freezing.

The numerical calculation has modeled in the framework of the phase field method with a Cahn–Hilliard formulation of a free energy functional.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The present study involved the development of a value-added comminution process for different recycled meat processing by-products such as bones for management of waste products. The paper aims to discuss these issues.

An indigenous cryo-grinding system was developed and pilot scale comminution tests were carried out on goat and hen bones under different temperature conditions ranging between −15°C and −40°C and sample pre-conditioning adopting liquid nitrogen as a grinding medium.

Cryo comminution produces finer, uniform particle sizes, increased specific surface area per unit mass with lesser specific energy consumption in comparison to room temperature comminution. Breakage behavior studies showed that hardness (609-685 MPa) and brittleness (24-29 m−1/2) and strain energy decreased (3.1-1.1 N-m) as the temperature was lowered. Weight mean diameter, specific energy consumption under ambient and cryogenic conditions, respectively, were 125 and 80 μm, 1,303 and 1,108 kJ/kg. The process developed attempts to eliminate environmental pollution by reducing food wastes generated and incorporates value to waste products.

A value-added comminution process for meat processing by-products such as bones was developed to reduce food wastes generated as well as environmental pollution. The process aims to improve public health stressing the importance of recycling through the management of food waste products. Public and private organizations can act as profit centers generating significant revenue and employment by adopting the process.

DOMINATING the outside exhibition at Le Bourget was the enormous Antonov An‐225 with the Buran space shuttle on top. Weighing some 600 tonnes and designed to carry loads of up to 250 tonnes, the An‐225 was part of a very extensive Soviet aircraft presence, both on the ground and in the flying display. The only truly new Western airliner was the ATR 72 but many civil and military fixed and rotating‐wing aircraft were making their first appearance at the Paris Show. A variety of products were featured, either with work currently being undertaken or in project form and these were highlighted by the expected launch of the Airbus A321 (stretched A320) and news of turboprop and turbofan regional airliners of around 50 seats to be produced in the next few years. Large engine participation was emphasised by the recently‐named Rolls‐Royce Trent and General Electric announced the development of entirely new engines for use on large twins in the mid‐1990's. Other manufacturers are striving to produce powerplants specifically tailored for the new commuter aircraft. Avionics systems and materials were characterised by new developments, the latter featuring in particular, metal matrix composites.