Numerical Analysis of the Constrained Blister Test

The constrained blister test is investigated through finite element analysis to determine the applicabilities and the limitations of the new technique. Numerical results confirm that the strain energy release rate asymptotically approaches a constant value. These results also show that the test technique and the approximate solution for strain energy release rate are applicable for some practical cases.     

Desalination and the commons: tragedy or triumph?

A policy is more likely to be economically efficient when its costs and benefits fall on the same group, but politicians can allocate costs and benefits to different groups within their jurisdictional commons. This article examines the distribution of costs and benefits from desalination projects using examples from San Diego, Almería and Riyadh. The examples illustrate how mismatches between costs and benefits can persist or change as politicians adjust the policy portfolio to balance inefficiency and political risk.     

The effect of axial pressure gradient on extruder mixing characteristics

Many twin screw extruders are operated in the starve-fed mode with the majority of the extruder having partially-filled channels. There will always be regions of totally filled channels due to the presence of the die or reverse elements. The authors experimentally show the effect of the change of percent drag flow on the rate of distributive mixing in the co-rotating and counter-rotating twin screw extruder. Optimum operating conditions for distributive mixing are identified experimentally and verified theoretically.     

A review of attacks and security approaches in open multi-agent systems

Open multi-agent systems (MASs) have growing popularity in the Multi-agent Systems community and are predicted to have many applications in future, as large scale distributed systems become more widespread. A major practical limitation to open MASs is security because the openness of such systems negates many traditional security solutions. In this paper we introduce and classify main attacks on open MASs. We then survey and analyse various security techniques in the literature and categorise them under prevention and detection approaches. Finally, we suggest which security technique is an appropriate countermeasure for which classes of attack.     

Endogenous Movement and Equilibrium Selection in Spatial Coordination Games

We study the effects of agent movement on equilibrium selection in network based spatial coordination games with Pareto dominant and risk dominant Nash equilibria. Our primary interest is in understanding how endogenous partner selection on networks influences equilibrium selection in games with multiple equilibria. We use agent based models and best response behaviors of agents to study our questions of interest. In general, we find that allowing agents to move and choose new game play partners greatly increases the probability of attaining the Pareto dominant Nash equilibrium in coordination games. We also find that agent diversity increases the ability of agents to attain larger payoffs on average.     

Excess Gibbs free energy and excess enthalpy for mixtures of benzene and 1,1,2-trichlorotrifluoroethane

The rapid measurement of static vapour pressures of binary liquid mixtures as a function of composition by a new continuous-dilution apparatus is described. These measurements, together with the computed excess Gibbs free energies, are reported for mixtures of benzene and 1,1,2-trichlorotrifluoroethane at 283.30, 287.83, 293.21, 298.21, 303.06 and 308.15 K over the full composition range, and are compared with the results of Linford and Hildebrand. The excess enthalpies were measured directly at 303.15 K using a batch calorimeter. The equimolar excess enthalpy is + 754 J mol^?1, which is close to the value, + 727 J mol^?1, calculated from the temperature dependence of the computed equimolar excess Gibbs free energies.     

Thermal alteration of a cyclic fatty acid produced by a flaxseed extract

Methyl 8-[2-(cis-pent-2′-enyl)-3-oxo-cis-cyclopent-4-enyl] octanoate (I) is the methyl ester of a cyclic fatty acid synthesized enzymically from an incubation of linolenic acid with an extract of flaxseed (Linum usitatissimum L.). A proposed trivial name for I is methyl 12-oxo-cis-10, 15-phytodienoate (12-oxo-PDA). The evidence presented indicated that compound I has thecis configuration of the carbon chains with respect to the cyclopentenone ring. Treatment with acid, base, or heat isomerized I to a second product (II) that has thetrans configuration of the carbon chains. Prolonged heat treatment of II yielded a third cyclic product, methyl 12-oxo-9(13),cis-15-phytodienoate (III).     

Fast training procedure for Viola–Jones type object detectors using Laplacian clutter models

This paper presents a fast training strategy for the Viola–Jones (VJ) type object-detection systems. The VJ object- detection system, popular for its high accuracy at real-time testing speeds, has a drawback that it is slow to train. A face detector, for example, can take days to train. In content-based image retrieval (CBIR), where search needs to be performed instantaneously, VJ’s long training time is not affordable. Therefore, VJ’s method is hardly used for such applications. This paper proposes two modifications to the training algorithm of VJ-type object detection systems which reduces the training time to the order of seconds. Firstly, Laplacian clutter (non-object) models are used to train the weak classifier, thus eliminating the need to read and evaluate thousands of clutter images. Secondly, the training procedure is simplified by removing the time-consuming AdaBoost-based feature selection procedure. An object detector, trained with 500 images, approximately takes 2 s for training in a conventional 3 GHz machine. Our results show that the accuracy of the detector, built with the proposed approach, is inferior to that of VJ for difficult object class such as frontal faces. However, for objects with lesser degree of intra-class variations such as hearts, state-of-the-art accuracy can be obtained. Importantly, for CBIR applications, the fast testing speed of the VJ type object detector is maintained.     

Scrolls and nested tubes in multiwall carbon nanotubes

Recent high-resolution transmission electron microscopy (HREM) studies of multiwalled carbon nanotubes (MWCNTs) reveal a class of defects analogous to edge dislocations in a crystal. These defects are believed to mark the transition from scrolls on one side to nested tubes on the other. On the tube side, layer spacing becomes irregular. Analysis of the helicity of the tubes shows a strong correlation between diameter and helicity. This suggests that the organizing principle for the tubes is not Van der Waals forces, as in the case of graphite or turbostratic carbon, but preservation of helicity. Based on these observations and total energy calculations, the authors speculate that graphene monolayers initially form scrolls and subsequently transform into multiwall nanotubes through the progression of defects. Scrolls and nested tubes thus coexist within a single MWNT.     

Microfluidics for particle synthesis from photocrosslinkable materials

This paper is a review of microfluidics for particle synthesis from photocrosslinkable materials. Microfluidics for particle synthesis is rapidly gaining attention as a viable method for the synthesis of particles with applications in drug delivery, security, abrasives, rheology, catalysis and other areas. Particle synthesis can follow several schemes, but the focus of this review is particle synthesis from photocrosslinkable materials. In these systems, solid particles are formed by the light-initiated cross-linking of precursor materials. This review begins with a discussion of photocrosslinkable materials, typically synthetic hydrogels for particle synthesis applications. Next, polydimethyl siloxane and glass devices are presented as the primary microfluidic devices for synthesis from photocrosslinkable materials. Then, the review discusses three types of polymeric particles: spherical, spheroidal and Janus. Subsequently, composite particles and metal or metal oxide particles are discussed. The review closes with a discussion of particle throughput and the outlook for the field of particle synthesis from photocrosslinkable materials.