Professor Rodney Howes, 1943–2005

Strategic IT implementation decisions for major construction projects in Hong Kong are subject to various forces or factors identified in previous research—such as external forces, technological factors and organizational factors. The aim of this research was to examine the relationship (if any) between these families of forces and evaluate their impact, individually and collectively. A complex combination of several families of forces/factors that affect decision making was found to be ‘temporal’ with respect to project teams on major projects in Hong Kong. The research was underpinned by a broad questionnaire survey to establish ‘current practice’ before in‐depth analysis of the forces by means of a case study followed by interviews with industry leaders to confirm the results. It was found that respondents (n = 33) ordered cost, security and confidentiality as the most influential factors affecting IT implementation. A difference was found in the perceptions of ‘hired‐in’ project‐based staff in joint ventures and ‘permanent staff’ of single companies, the former evaluating IT performance more highly but evaluating the strategic use of, and user satisfaction with, IT significantly lower. The major constraint on IT implementation was found to be lack of budget, not cost per se. It is concluded that the temporal factors that apply to implementing innovative IT technology in project teams are relevant to different team members at different stages in the project life cycle and these factors are conditioned by a set of business conditions applying to project‐specific coalition organizations that are different from those that apply to single‐entity organizations.     

Superhydrophobic Graphene Foams

The static and dynamic wetting properties of a 3D graphene foam network are reported. The foam is synthesized using template‐directed chemical vapor deposition and contains pores several hundred micrometers in dimension while the walls of the foam comprise few‐layer graphene sheets that are coated with Teflon. Water contact angle measurements reveal that the foam is superhydrophobic with an advancing contact angle of ～163 degrees while the receding contact angle is ～143 degrees. The extremely water repellent nature of the foam is also confirmed when impacting water droplets are able to completely rebound from the surface. Such superhydrophobic graphene foams show potential in a variety of applications ranging from anti‐sticking and self‐cleaning to anti‐corrosion and low‐friction coatings.     

Safety stock determination based on parametric lead time and demand information

In many production environments where demand and lead times are variable, significant levels of safety stock inventory are required to assure timely production and delivery of the final product. Traditional models to determine the appropriate safety stock level may result in more safety stocks at sub-assembly and finished goods levels than necessary and thus lead to higher inventory carrying costs than desired. Such models generally incorrectly assume that the demand during the lead time follows a normal distribution. This paper revisits and analyses a re-ordering point inventory model developed by Estes (1973 Estes, R. 1973. The joint probability approach and reorder point determination. Journal of Production and Inventory Management, 14(2): 50–56.  [Google Scholar]) that accounts for demand and lead time variability without making any particular distributional assumptions. Instead, it focuses on historical data to determine the possible outcomes of the replenishment cycle. We compare the proposed model with the traditional model by conducting simulation analysis using three data sets obtained from an electronics manufacturer. The results indicate that the proposed model yields much closer to target service levels and lower inventory carrying costs than the traditional model, regardless of the data set used.     

MOSAR: A Multi-Objective Strategy for Hiding Sensitive Association Rules Using Genetic Algorithm

It seems very realistic to find different aspects in a problem solution like rule hiding. Based on this point of view, Availability, Sensitivity, and Conflict are defined as the novel measurements to detect specific transactions in each transactional database in an effective way. At this point, it will be helpful for decision makers to consider such aspects on their solutions to hide sensitive association rules (ARs). Accordingly, the authors put forward a fitness function of genetic algorithm adjusted to the proposed measurements for hiding sensitive rules of the original database. Experimental study shows that the MOSAR algorithm outperforms traditional approach (Decrease Support of Right Hand Side algorithm) in view of reducing ARs in conflict with sensitive ARs, as a side effect in sensitive rule hiding process. Furthermore, this approach is applicable to do its best in banking systems, where database is to be shared through the networks, to protect strategic information after a serious attack.     

A Study on the Formation of Intermetallics During the Heat Treatment of Explosively Welded Al-Ti Multilayers

Metallic–intermetallic laminate composites are promising materials for many applications, namely, in the aerospace industry. Ti/TiAl₃ laminates are one of the interesting laminate composites, which are mostly used in aerospace applications. In this work, commercially pure aluminum and titanium sheets were explosively joined. The multilayer samples were annealed between 1 and 260 hours at 903 K (630 °C) in ambient atmosphere, and the formation and growth of the intermetallic compound at the Ti/Al interface were monitored. Microstructural investigations were carried out using optical and scanning electron microscopes equipped with energy-dispersive spectroscopy and the X-ray diffraction technique. The microhardness profile of the layers was also determined. The thickness and type of Al-Ti intermetallics were determined. It was found that the only intermetallic phase observed in the interfaces was TiAl₃. It was also shown that two mechanisms for TiAl₃ growth exist: reaction and diffusion controlled. The growth exponent was equal to 0.94 for the reaction-controlled mechanism (first step) and 0.31 for the diffusion-controlled mechanism (second step). These values were in good agreement with theoretical values (1 and 0.5 for the first and second steps, respectively). Based on the results of this research, a kinetic model for the formation and growth of TiAl₃ intermetallic phase was proposed.     

Investigation of rare earth sealing of porous micro-arc oxidation coating formed on AZ91D magnesium alloy

Magnesium and its alloys have been used in many industries, but they are reactive and require protection against aggressive envi-ronments. In this study, oxide coatings were applied on AZ91D magnesium alloy using micro-arc oxidation (MAO) process. Then, in order to seal the pores of the MAO coatings, the samples were immersed in cerium bath for different times. The surface morphologies and composi-tions of the coatings were analyzed by scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDS), respectively. The corrosion behavior of the coatings was investigated with electrochemical impedance spectroscopy (EIS) and potentiodynamic polariza-tion tests in 3.5 wt.% NaCl solution. The amount of the porosity of the coating was measured by electrochemical method. It was found that the sealing treatments by immersion in cerium bath successfully sealed the pores of the MAO coatings. The results of the corrosion tests showed that the MAO coating which was sealed in Ce bath for 10 min enhanced the corrosion resistance of the substrate significantly. Fur-thermore, this coating had the lowest amount of the porosity among the coatings.)     

Cross section recondensation method via generalized energy condensation theory

The standard multigroup method used in whole-core reactor analysis relies on energy condensed (coarse-group) cross sections generated from single lattice cell calculations, typically with specular reflective boundary conditions. Because these boundary conditions are an approximation and not representative of the core environment for that lattice, an error is introduced in the core solution (both eigenvalue and flux). As current and next generation reactors trend toward increasing assembly and core heterogeneity, this error becomes more significant. The method presented here corrects for this error by generating updated coarse-group cross sections on-the-fly within whole-core reactor calculations without resorting to additional cell calculations. In this paper, the fine-group core flux is unfolded by making use of the recently published Generalized Condensation Theory and the cross sections are recondensed at the whole-core level. By iteratively performing this recondensation, an improved core solution is found in which the core-environment has been fully taken into account. This recondensation method is both easy to implement and computationally very efficient because it requires precomputation and storage of only the energy integrals and fine-group cross sections. In this work, the theoretical basis and development of cross section recondensation is presented, and the method is verified with several sample problems.     

Optimal characterization of a microwave transistor using grey wolf algorithms

Analog Integrated Circuits and Signal Processing - Modern time microwave stages require low power consumption, low size, low-noise amplifier (LNA) designs with high-performance measures. These...