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To determine the optimal dimensions for a stacked micro‐channel using the genetic algorithms (GAs) under different flow constraints.

GA is used as an optimization tool for optimizing the thermal resistance of a stacked micro‐channel under different flow constraints obtained by using the one dimensional (1D) and two dimensional (2D) finite element methods (FEM) and by thermal resistance network model as well (proposed by earlier researcher). The 2D FEM is used to study the effect of two dimensional heat conduction in the micro‐channel material. Some parametric studies are carried out to determine the resulting performance of the stacked micro‐channel. Different number of layers of the stacked micro‐channel is also investigated to study its effect on the minimum thermal resistance.

The results obtained from the 1D FEM analysis compare well with those obtained from the thermal resistance network model. However, the 2D FEM analysis results in lower thermal resistance and, therefore, the importance of considering the conduction in two dimensions in the micro‐channel is highlighted.

The analysis is valid for constant properties fluid and for steady‐state conditions. The top‐most surfaces as well as the side surfaces of the micro‐channel are considered adiabatic.

The method is very useful for practical design of micro‐channel heat‐sinks.

FEM analyses of stacked micro‐channel can be easily implemented in the optimization procedure for obtaining the dimensions of the stacked micro‐channel heat‐sinks for minimum thermal resistance.

Seeks to help managers to recognize different types of resistance and how to react to them. Categorizes types of resistance (resistance quadrants) and presents questions to help identify the personality of the resistor. Resistance to change can be intentional or unintentional, covert or overt. Describes causes of resistance and presents diagnostic questions. Managers with self‐awareness and a sense of humour are most successful in overcoming resistance to change.

This paper examines organizational change, focusing on the distinction of changes according to their scope and presenting a typology of evolutionary and strategic changes. It also offers an in‐depth study of resistance to change. Through empirical research, the paper analyzes the importance of the sources of resistance to change defined theoretically, and considers both types of changes. The article shows which sources of resistance differ most, according to the scope of change, offering hints about where organizations should pay special attention when initiating a change process.

Traditionally, resistance has been cast as adversarial ‐ the enemy of change that must be defeated if change is to be successful. While it is apparent that classical management theory viewed resistance in such a manner, recent literature contains much evidence that suggests resistance may indeed be useful and is not to be simply discounted. Present day suggestions and prescriptions for managing resistance have evidently disregarded this research and left little room for utility in resistance. This paper argues that the difficulty of organisational change is often exacerbated by the mismanagement of resistance derived from a simple set of assumptions that misunderstand resistance’s essential nature. It is suggested that management may greatly benefit from techniques that carefully manage resistance to change by looking for ways of utilising it rather than overcoming it.

This article discusses power and resistance in commercial environments. It finds that a company's ability to realize its goals (fulfill its strategy) is a function of its ability to deal with resistance; to recognize it first of all, and then to find ways to overcome it, which inevitably involve the use of power in some form.

The paper examines strategies used by pharmaceutical companies for getting drugs prescribed, programs by credit card companies to defeat resistance to card proliferation, and strategies by software companies to overcome resistance in OEMs to product acceptance.

The author concludes that the success of the products/companies studied is explained by their capacity for overcoming resistance, that it cannot be attributed to a compelling vision statement, or a five‐year plan, a competitive analysis, or any of the other strategy approaches used by the majority of companies.

All companies, presumably, have goals, and all companies operate in power‐dependent environments, and all companies, whether they recognize it or not, face resistance beyond the existence of competitors. The key is to be able to see resistance, and to understand how it is manifesting itself against a specific goal.

The thesis of the paper is important to practitioners because it gets them thinking about resistance beyond the existence of competitors. It reveals other, more powerful sources of opposition, and gives them a new platform for strategy based on finding power over resistance.

Termination resistances can affect the behaviour of thin‐film resistors. Depending on the dimensions of a resistor both the TCR and the long‐term stability will be affected, while the termination resistance forms part of the practical resistance value. This paper deals with the results of an investigation concerning the influence of termination resistances with respect to the behaviour of thin‐film resistors. Three thin‐fiim technologies were investigated. Values for the resistance, TCR and ageing drifts of both the bulk material and the terminations will be discussed. Some remarks on the structure of a termination will be mentioned.

The purpose of this paper is to optimize the configuration sizes of micro‐channel cooling heat sink using the thermal resistance network model. The optimized micro‐channel heat sink is simulated by computational fluid dynamics method, and the total thermal resistance is calculated to compare with that of thermal resistance network model.

Taking the thermal resistance and the pressure drop as goal functions, a multi‐objective optimization model was proposed for the micro‐channel cooling heat sink based on the thermal resistance net work model. The Sequential Quadratic Programming procedure was used to do the optimization design of the structure size of the micro‐channel. The optimized micro‐channel heat sink was numerically simulated by computational fluid dynamics (CFD) software.

For the heat sink to cool a chip with the sizes of L × W = 2.5 mm × 2.5 mm and the power of 8 W, the optimized width and height of the micro‐channel are 154 μm and 1,000 μm, respectively, and its corresponding total thermal resistance is 8.255 K/W. According to the simulation results, the total thermal resistance of whole micro‐channel heat sink R_total is 7.596 K/W, which agrees well with the analysis result of thermal resistance network model.

The convection heat transfer coefficient is calculated approximatively here for convenience, and that may induce some errors. Originality/value –The maximum difference in temperature of the optimized micro‐channel cooling heat sink is 59.064 K, which may satisfy the requirement for removal of high heat flux in new‐generation chips.

The aim of this work was to validate the Wilson and Laing theoretical mathematical model for estimating the intrinsic “dry” thermal resistance of upper‐bedding, and compare the two‐dimensional models commonly used to estimate the “dry” thermal resistance of bedding in use, with the actual intrinsic “dry” thermal resistance measured using an infant thermal manikin. The Wilson and Laing model was the only model used adequately to estimate the intrinsic “dry” thermal used resistance of materials arranged over the infant thermal manikin. Estimation of intrinsic “dry” thermal resistance of bedding during use is not adequate using two‐dimensional models. Further investigation into the relationship between thermal resistance, conditions of use, and SIDS using the Wilson and Laing model is recommended.

Pilling and abrasion resistance are two of the most important mechanical properties of the fabric that influence the appearance and performance of the fabric, particularly in the case of knitted fabrics. Since, these fabric features are affected by fabric structure the aim of present research is to investigate how utilizing miss stitches and tuck stitches in the fabric structure for design purposes will influence the pilling and abrasion resistance of interlock weft-knitted fabrics.

In this research, interlock fabrics with different number of miss or tuck stitches on successive Wales were produced and pilling performance and abrasion resistance of the fabrics were investigated.

The results revealed that increasing the number of miss/tuck stitches on successive Wales decreases the abrasion resistance and enhances the pilling tendency of the fabric. The presence of miss/tuck stitches on both sides of the fabric improves the abrasion resistance and pilling performance of the fabric compared to fabrics containing these stitches on one side of the fabric. Furthermore, the fabric resistance against abrasion and pilling is higher in fabrics consisting of miss stitches compared to fabrics consisting of tuck stitches.

The use of tuck and miss stitches in designing the weft-knitted fabrics is a common method for producing fabrics with variety of knit patterns. Since pilling and abrasion resistance of the fabric influence on its appearance and performance, and none of the previous research studied the pilling and abrasion resistance of interlock-knitted fabrics from the point of presence of tuck and miss stitches on successive Wales of the fabric, this subject has been surveyed in the present research.

The purpose of this paper is to reveal the dynamic contact characteristics of the slip ring. Dynamic contact resistance models considering wear and self-excited were established based on fractal theory.

The effects of tangential velocity, stiffness and damping coefficient on dynamic contact resistance are studied. The relationships between fractal parameters, wear time and contact parameters are revealed.

The results show that the total contact area decreases with the friction coefficient and fractal roughness under the same load. Self-excited vibration occurs at a low speed (less than 0.6 m/s). It transforms from stick-slip motion at 0.4 m/s to pure sliding at 0.5 m/s. A high stiffness makes contact resistance fluctuate violently, while increasing the damping coefficient can suppress the self-excited vibration and reduce the dynamic contact resistance. The fractal contact resistance model considering wear is established based on the fractal parameters models. The validity of the model is verified by the wear tests.

The results have a great significance to study the electrical contact behavior of conductive slip ring.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2023-0300/