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By reducing the coating thickness of the weak scattering source, the coating weight of the absorbing material can be reduced by 35% with little effect on the RCS.

To alleviate the weight-increasing problem caused by a large number of coating of absorbing materials, a method for zonal coating of absorbing materials for a stealth helicopter was proposed. By appropriately reducing the thickness of the coating at the secondary scattering locations, the amount of coating used is significantly reduced.

Compared with the full-coated, the zonal coating scheme achieves the corresponding RCS reduction effect.

Zonal coating design can achieve the effect of reducing coating weight and cost.

The effects of different coating methods on RCS were verified by electromagnetic scattering simulation, and the applicability of the zonal coating design of the absorbing material to the stealth helicopter was verified.

The numerical simulation of practical thermal processes is generally complicated because of multiple transport mechanisms and complex phenomena that commonly arise. In addition, the materials encountered are often not easily characterized and typically involve large property changes over the ranges of interest. The boundary conditions may not be properly defined and or may be unknown. However, it is important to obtain accurate and dependable numerical results from the simulation in order to study, design, and optimize most practical thermal processes of current and future interest. The purpose of this paper is to focus on the main challenges that are encountered in obtaining accurate numerical simulation results on practical thermal processes and systems.

A wide range of thermal systems is considered and the challenges faced in the numerical simulation are outlined. The methods that may be used to meet these challenges are presented in terms of grid, solution strategies, multiscale modeling and combined mechanisms. The models employed must be validated and the accuracy of the simulation results established if the simulation is to form the basis for improving existing systems and developing new ones.

Of particular interest are concerns like verification and validation, imposition of appropriate boundary conditions, and modelling of complex, multimode transport phenomena in multiple scales. Additional effects such as viscous dissipation, surface tension, buoyancy and rarefaction that could arise and complicate the modelling are discussed. Uncertainties that arise in material properties and in boundary conditions are also important in design and optimization. Large variations in the geometry and coupled multiple regions are also discussed.

The paper is largely focused on numerical modeling and simulation. Experimental data are considered mainly for validation and for physical insight.

A wide variety of practical systems, ranging from materials processing to energy, cooling, and transportation is considered.

Future needs in this interesting and challenging area are also outlined in the paper.

This article focuses on the comparative study of annular wire‐coating flows with polymer melt materials. Different process designs are considered of pressure‐ and tube‐tooling, complementing earlier studies on individual designs. A novel mass‐balance free‐surface location technique is proposed. The polymeric materials are represented via shear‐thinning, differential viscoelastic constitutive models, taken of exponential Phan‐Thien/Tanner form. Simulations are conducted for these industrial problems through distributed parallel computation, using a semi‐implicit time‐stepping Taylor‐Galerkin/pressure‐correction algorithm. On typical field results and by comparing short‐against full‐die pressure‐tooling solutions, shear‐rates are observed to increase ten fold, while strain rates increase one hundred times. Tube‐tooling shear and extension‐rates are one quarter of those for pressure‐tooling. These findings across design options, have considerable bearing on the appropriateness of choice for the respective process involved. Parallel finite element results are generated on a homogeneous network of Intel‐chip workstations, running PVM (Parallel Vitual Machine) protocol over a Solaris operating system. Parallel timings yield practically ideal linear speed‐up over the set number of processors.

The purpose of this paper is to model radiation ovens and to propose a method capable of designing this kind of oven for the paint curing application. Providing a uniform cure condition on the body, especially bodies of complicated geometries, needs accurately‐designed ovens. An algorithm with high speed and high convergence capability is the most serious requirement for designing ovens of this kind.

In this paper, the state of the art in dynamic optimisation of radiation paint cure ovens is reviewed and a novel objective function, based on paint cure window, is proposed to be applied for designing radiation ovens. It has been shown that the proper definition of the objective function in such problems makes the mathematical model more robust and hence facilitates the convergence of the design iterations.

The computational results provide some information regarding the design space topology and show that the proposed objective function speeds up the convergence of the design procedure by an order of magnitude as compared to the currently used industrial‐standard objective function.

Determination of curing condition is an important requirement for designing a new oven or changing the working condition of an existing oven. In this research, a practical method is proposed for improving design procedure of cure ovens to make the method both time and cost efficient. The method is specifically implemented on paint cure ovens.

The quality of cured paint is usually a prominent issue that directly takes influence from the curing condition of ovens. For the complex geometries of curing body in commonly designed ovens, some areas are not properly cured or may be burnt. This issue is a significant defect in coating industry. Designing ovens with the proposed method in this paper guaranties the provided curing condition by the oven and therefore the curing quality.

This paper seeks to discuss the numerical modeling of the transport processes that frequently arise in practical thermal systems and involve complexities such as property variations with temperature or with the shear rate in the flow, complicated regions, conjugate mechanisms, chemical reactions and combined mass transfer, and intricate boundary conditions.

The basic approaches that may be adopted in order to study such processes are discussed. Considerations for accurate numerical modeling are also discussed. The link between the process and the resulting product is critical in many systems such as those in manufacturing. The computational difficulties that result from the non‐Newtonian behavior of the fluid or from the strong temperature dependence of viscosity are considered in detail. Similarly, complex geometry, free surface flow, moving boundaries, combined mechanisms, and simulation of appropriate boundary conditions are important in several processes and are discussed.

Some of the important techniques to treat the problems that arise in numerical simulation are presented. Common errors that lead to inaccurate or invalid results are outlined. A few practical processes are considered in greater detail to quantify and illustrate these approaches. Validation of the numerical model is a particularly important aspect and is discussed in terms of existing results, as well as development of experimental arrangements to provide inputs for satisfactory validation.

Practical thermal processes involve a wide variety of complexities. The paper presents some of the important ones and discusses approaches to deal with them. The paper will be of particular value to the numerical simulation of complicated thermal processes in order to design, control or optimize them to achieve desired thermal processing.

Transforming a production-oriented firm into a marketing-oriented firm; aligning marketing strategy of local companies in globalizing emerging markets; creating sustainable competitive advantage.

Post graduate management courses in marketing management, strategic marketing, international marketing, business strategy.

This case is about how the leader in the Indian paper industry, Ballarpur Industries Ltd (BILT), is proactively transforming a production-oriented firm to a marketing-oriented firm to compete in the globalizing emerging market scenario, in the wake of economic liberalisation. It requires the participants to evaluate the impact of marketing initiatives made, and align BILT's marketing strategy to leverage it's strengths and help create sustainable competitive advantage.

To understand the need for local companies in emerging markets to proactively align marketing strategy to build competitive advantage in the globalizing industry.

Teaching notes.

Experimental results play a crucial role in the validation of mathematical and numerical models for a variety of basic and applied thermal transport problems. The purpose of this paper is to focus on the role played by experimentation in an accurate numerical simulation of thermal processes and systems.

The paper takes the form of a numerical simulation combined with experimentation. The paper presents various circumstances where the numerical simulation may be efficiently combined with experimentation, and indeed driven by experimental data, to obtain accurate, valid and realistic numerical predictions.

The paper demonstrates validation and accuracy of numerical simulation.

This paper is an important first step in combining experiments and simulation for complex thermal systems.

This paper aims to describe the control software of a novel manufacturing system called plasma-assisted bio-extrusion system (PABS), designed to produce complex multi-material and functionally graded scaffolds for tissue engineering applications. This fabrication system combines multiple pressure-assisted and screw-assisted printing heads and plasma jets. Control software allows the users to create single or multi-material constructs with uniform pore size or pore size gradients by changing the operation parameters, such as geometric parameters, lay-down pattern, filament distance, feed rate and layer thickness, and to produce functional graded scaffolds with different layer-by-layer coating/surface modification strategies by using the plasma modification system.

MATLAB GUI is used to develop the software, including the design of the user interface and the implementation of all mathematical programing for both multi-extrusion and plasma modification systems.

Based on the user definition, G programing codes are generated, enabling full integration and synchronization with the hardware of PABS. Single, multi-material and functionally graded scaffolds can be obtained by manipulating different materials, scaffold designs and processing parameters. The software is easy to use, allowing the efficient control of the PABS even for the fabrication of complex scaffolds.

This paper introduces a novel additive manufacturing system for tissue engineering applications describing in detail the software developed to control the system. This new fabrication system represents a step forward regarding the current state-of-the-art technology in the field of biomanufacturing, enabling the design and fabrication of more effective scaffolds matching the mechanical and surface characteristics of the surrounding tissue and enabling the incorporation of high number of cells uniformly distributed and the introduction of multiple cell types with positional specificity.

NO document issued by the National Board for Prices and Incomes is of more importance to people engaged in work study than Report 83 on Job Evaluation. It lists nine definitions by various authorities but contents itself with a fairly simple one; the comparison of jobs by the use of formal and systematic procedures, set down on paper and adhered to as distinct from rule of thumb methods, with subsequent analysis determining the relative positions of jobs in a wage structure.

The long‐term durability of cement becomes an important challenge in oil and gas wells due to the aggressive acid gas. H₂S has been found in more and more wells. The purpose of this research was to add polymer latex to the Class G cement in order to promote the H₂S corrosion resistance of oilwell cement.

The water loss and thickening time of cement slurry and compressive strength and gas permeability of bond cement were investigated to determine the cement formulation. The corrosion resistance of the polymer cement was compared to base Class G cement in solution with 1.8 MPa H₂S at 120°C.

The optimum concentration of polystyrene latex was determined as 5 percent. The permeability change, compressive strength loss and corrosion ratio of latex cement were all lower than for the base Class G cement. The electrochemical impedance spectroscopy results and microstructure details confirmed that the latex cement had stronger resistance to the aggressive medium. Thus, latex cement had excellent corrosion resistance to H₂S.

The findings of this study can further improve the sulfide resistance of Class G cement. Two roles of the polystyrene latex were observed in the cement, including interstitial in‐filling of the pore structure and packing around hydration products, which are proposed to properly explain the results.