Simultaneous configuration of platform products and manufacturing supply chains

The product platform concept represents a powerful approach for manufacturers to compete cost-effectively in a global market that requires diverse product range, quick time to market, and rapid responses to supply sources. A key challenge is how to strike a balance between platform commonality and modularity. When a manufacturer outsources its raw materials or module options, the supplier capabilities and production costs should be considered. This paper discusses optimizing decision variables for simultaneously configuring not only platform-based product variants but also their supply chain. We develop a mixed-integer programming model that integrates both platform product design and material purchase decisions based on cost drivers sensitive to commonality and modularity. Theoretical analysis of the model yields two properties, allowing us to further simplify the model and thus help in developing an effective solution algorithm. A numerical example is presented to illustrate how manufacturers strive to dynamically adjust their product design strategies in response to changes in the market demands and/or supply base.     

Elemental characterisation of Cabernet Sauvignon wines using Particle-Induced X-ray Emission (PIXE)

The elemental composition of 2002 Cabernet Sauvignon wines from four different regions of Rio Grande do Sul state (Brazil) was determined using Particle-Induced X-ray Emission (PIXE) technique. In total, wines from 13 different vineyards were studied. Particular attention was given to wines stemming from Vale dos Vinhedos which is one of the most important wine producing regions in Brazil. Typical PIXE spectra consisted of elements with atomic number between 11 and 38 such as P, S, K, Ti, Mn, Fe, Cu, Zn and Rb. Physicochemical variables such as volatile acidity, alcohol, pH and dry extract were also determined for some wines. Variations in the elemental concentrations among wines from Vale dos Vinhedos and from different regions were observed. In general our results are in good agreement with previous measurements of Brazilian wines. With respect to European wines, our results are characterised by relatively low concentrations of Cu and Zn and high concentration of Rb.     

How to Attain an Ultralow Interfacial Tension and a Three-Phase Behavior with a Surfactant Formulation for Enhanced Oil Recovery: A Review. Part 2. Performance Improvement Trends from Winsor’s Premise to Currently Proposed Inter- and Intra-Molecular Mixtures

The minimum interfacial tension occurrence along a formulation scan at the so-called optimum formulation is discussed to be related to the interfacial curvature. The attained minimum tension is inversely proportional to the domain size of the bicontinuous microemulsion and to the interfacial layer rigidity, but no accurate prediction is available. The data from a very simple ternary system made of pure products accurately follows the correlation for optimum formulation, and exhibit a linear relationship between the performance index as the logarithm of the minimum tension at optimum, and the formulation variables. This relation is probably too simple when the number of variables is increased as in practical cases. The review of published data for more realistic systems proposed for enhanced oil recovery over the past 30 years indicates a general guidelines following Winsor’s basic studies concerning the surfactant–oil–water interfacial interactions. It is well known that the major performance benefits are achieved by blending amphiphilic species at the interface as intermolecular or intramolecular mixtures, sometimes in extremely complex formulations. The complexity is such that a good knowledge of the possible trends and an experienced practical know-how to avoid trial and error are important for the practitioner in enhanced oil recovery.     

Synthesis and Physicochemical Characterization of Anionic Surfactants Derived from Cashew Nut Shell Oil

Carboxylate derivatives of cardanol and anacardic acids, which are the main phenolic components of cashew nut shell oil were prepared and tested as anionic surfactants. They lower the surface tension, exhibit a critical micelle concentration, and produce microemulsions in mixtures with dodecyl sulfate. The values of their characteristic parameters in the hydrophilic–lipophilic deviation scale attained by the unidimensional formulation scan method typify them as hydrophilic surfactants.     

Multimedia virtual circuit model for MPEG on ATM networks

A Multimedia Virtual Circuit (MVC) model for MPEG (Motion Picture Experts Group) transmission demonstrates an efficient method to accommodate the bandwidth requirements of multiple sources. In our simulation we compare the leaky bucket system that requires client to reserve the maximum rate and the proposed MVC system. © 1998 John Wiley & Sons, Ltd.     

Glial Cell Activation and Oxidative Stress in Retinal Degeneration Induced by β-Alanine Caused Taurine Depletion and Light Exposure

We investigate glial cell activation and oxidative stress induced by taurine deficiency secondary to β-alanine administration and light exposure. Two months old Sprague-Dawley rats were divided into a control group and three experimental groups that were treated with 3% β-alanine in drinking water (taurine depleted) for two months, light exposed or both. Retinal and external thickness were measured in vivo at baseline and pre-processing with Spectral-Domain Optical Coherence Tomography (SD-OCT). Retinal cryostat cross sections were immunodetected with antibodies against various antigens to investigate microglial and macroglial cell reaction, photoreceptor outer segments, synaptic connections and oxidative stress. Taurine depletion caused a decrease in retinal thickness, shortening of photoreceptor outer segments, microglial cell activation, oxidative stress in the outer and inner nuclear layers and the ganglion cell layer and synaptic loss. These events were also observed in light exposed animals, which in addition showed photoreceptor death and macroglial cell reactivity. Light exposure under taurine depletion further increased glial cell reaction and oxidative stress. Finally, the retinal pigment epithelial cells were Fluorogold labeled and whole mounted, and we document that taurine depletion impairs their phagocytic capacity. We conclude that taurine depletion causes cell damage to various retinal layers including retinal pigment epithelial cells, photoreceptors and retinal ganglion cells, and increases the susceptibility of the photoreceptor outer segments to light damage. Thus, beta-alanine supplements should be used with caution.     

Structural characterisation and immunomodulatory property of an acidic polysaccharide from mycelial culture of Cordyceps sinensis fungus Cs-HK1

An acidic polysaccharide, designated AEPS-1, was fractionated from the exopolysaccharide (EPS) produced by a medicinal fungus Cordyceps sinensis Cs-HK1 in mycelial culture. The molecular structure of AEPS-1 was characterised and elucidated by spectral and chromatographic analyses, and through derivatization by periodate oxidation, Smith degradation and methylation. AEPS-1 was composed of glucopyranose (Glcp) and pyrano-glucuronic acid (GlcUp) in an 8:1 M ratio plus a trace amount of mannose, having an average molecular weight of about 36 kDa. AEPS-1 had a linear backbone of (1→3)-linked α-d-Glcp residues with two branches, α-d-Glcp and α-d-GlcUp, attached to the main chain by (1→6) glycosidic bonds at every seventh α-d-Glcp unit. Atomic force microscopy revealed that AEPS-1 formed large networks in water that are connected primarily with triple helical strands. In Raw264.7 macrophage cell cultures, AEPS-1, at suitable doses between 25 and 250 μg/ml, significantly stimulated the release of several major cytokines, demonstrating an immunomodulatory property.     

Finite element stress formulation for dynamic elastic-plastic analysis

The solution to wave propagation problems in solids with elastic-plastic material properties is obtained by using the finite element method directly in terms of the stresses. A variational principle due to Gurtin is modified by including a plastic strain tensor in the constitutive relationship. The resulting finite element equations, which represent the strain-displacement equations written in terms of the stresses, are simultaneous integral equations in time. With a transformation of variables, a set of simultaneous differential equations is obtained of the form$\text{H}\text{s}\text{?}\text{+ Qs+ Ve}{}_{\mathrm{p}}\text{= q(t)}$, where $\text{H}$ is a symmetric positive-semidefinite matrix, and $\text{Q}$ is a symmetric positive-definite matrix. The stresses and the plastic strains are represented by $\text{s}\text{?}$ and $\text{e}{}_{\mathrm{p}}$, respectively.Finite element equations are developed for an axisymmetric ring element with an arbitrary quadrilateral cross section in which the stresses and the plastic strains vary linearly along the sides of the elements. The equations are numerically integrated with respect to time by Newmark's generalized acceleration method.An iterative procedure is presented, which uses the finite element strain-displacement equations and the plasticity relationships, to determine the state of stress at the end of the time step. Several examples are used to demonstrate the solution technique for elastic and elastic-plastic problems.     

Design and implementation of heterogeneous distributed multimedia system using mosaic GSQL

With more and more computer users having access to the Internet, it is important for them to access the vast amount of information in an efficient and easy manner. This project explores one of the possibilities for providing an integrated system to the user to access the different types of media like text, image, audio and video stored in different databases on remote machines without the user having to know about the underlying mechanism involved in accessing the database. Such a system must hide the location of the remote data, retrieve the information, process the results and present it to the user. We have used the National Center for Supercomputer Applications (NCSA) Mosaic's Gateway Structured Query Language (GSQL), which enables a system developer to build input forms, query to the remote database in a relatively easy manner and present the results to the user. With the help of this prototype, the development time to build such an application is considerably reduced as compared with developing the same application using the existing Graphical User Interface (GUI) tools like the X-Window system.