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Ultrasonic additive manufacturing (UAM) is a rapid prototyping process through which multiple thin layers of material are sequentially ultrasonically welded together to form a finished part. While previous research into the peak temperatures experienced during UAM have been documented, a thorough examination of the heating and cooling curves has not been conducted to date.

For this study, UAM weldments made from aluminum 3003‐H18 tapes with embedded Type‐K thermocouples were examined. Finite element modeling was used to compare the theoretical thermal diffusion rates during heating to the observed heating patterns. A model was used to calculate the effective thermal diffusivity of the UAM build on cooling based on the observed cooling curves and curve fitting analysis.

Embedded thermocouple data revealed simultaneous temperature increases throughout all interfaces of the UAM build directly beneath the sonotrode. Modeling of the heating curves revealed a delay of at least 0.5 seconds should have existed if heating of lower interfaces was a result of thermal diffusion alone. As this is not the case, it was concluded that ultrasonic energy is absorbed and converted to heat at every interface beneath the sonotrode. The calculated thermal diffusivity of the build on cooling was less than 1 percent of the reported values of bulk aluminum, suggesting that voids and oxides along interfaces throughout the build may be inhibiting thermal diffusion through thermal contact resistance across the interface.

This work systematically analyzed the thermal profiles that develop during the UAM process. The simultaneous heating phenomenon presented here has not been documented by other research programs. The findings presented here will enable future researchers to develop more accurate models of the UAM process, potentially leading to improved UAM bond quality.

The purpose of this paper is to develop an effective framework for implementing Lean strategies in small- and medium-sized enterprises (SMEs) in the Kurdistan Region of Iraq (KRI).

Based on the integration of LM tools and techniques with the Malcolm Baldrige National Quality Award (MBNQA) criteria a systematic Lean implementation framework for manufacturing SMEs has been proposed. The core values, drivers and tools of the proposed framework were further developed based on case studies in three SMEs in the KRI.

Proposed framework is able to provide a simple pathway for SMEs to systematically implement Lean techniques in seven functional areas in order to create Lean culture in the organisation. Business performance measurement in terms of profitability, customer satisfaction, employee’s satisfaction, competitiveness growth and ergonomic improvement is presented in favour of evaluating Lean outcomes appropriately. It also presents the experience of small firms in implementing Lean programmes to show that Lean is valid in SMEs.

The framework concentrates only on the internal issues of the organisation, while external variables such as national culture and external support are excluded.

The framework assists improvements in SMEs that either initially attempt to start Lean journey or those that are at more advanced levels towards excellent-Lean manufacturing. The framework can also be used as a self-assessment model to determine the degree of Lean readiness.

To the best knowledge of the author, it is the first framework that integrates Lean techniques with MBNQA criteria to support Lean implementation in SMEs. It is also the first study regarding Lean-excellence in the KRI.

The Westland Lynx helicopter is a particularly fine example of the use of advanced fan technology in modern aircraft applications. The firm of Airscrew Howden have come a long way from their original manufacture of the wooden ‘prop’ but they still continue to play a very essential part in all types of aircraft flying today; this takes the form of sophisticated fan designs to cover a wide variety of special air‐movement requirements that can arise in this sector.

Electrical properties of biological tissues are known to be sensitive to physiological and pathological conditions of living organisms. For instance, human breast cancer or liver tumor cells have a significantly higher electrical conductivity than a healthy tissue. The paper aims to the new recently developed magnetoacoustic tomography with magnetic induction (MAT-MI) which can be deployed for electrical conductivity imaging of low-conductivity objects. Solving a test problem by using an analytical method is a useful exercise to check the validity of the more complex numerical finite element models. Such test problems are discussed in Chapter 3. The detailed analysis of an electromagnetic induction in low-conductivity objects is very important for the next steps in the tomographic process of image reconstruction. Finally, the image reconstruction examples for object’s complex shapes’ have been analyzed. The Lorentz force divergence reconstruction has been achieved with the help of time reversal algorithm.

In given arrangements the magnetic field and eddy current vectors satisfy the Maxwell partial differential equations. Applying the separation of variables method analytical solutions are obtained for an infinitely long conducting cylindrical segment in transient magnetic field. A special case for such a configuration is an infinitely long cylinder with longitudinal crack. The analytical solutions are compared with those obtained by using numerical procedures. For complex shapes of the object, the MAT-MI images have been calculated with the help of the finite element method and time reversal algorithm.

The finite element model developed for a MAT-MI forward problem has been validated by analytical formulas. Based on such a confirmation, the MAT-MI complex model has been defined and solved. The conditions allowing successful MAT-MI image reconstruction have been provided taking into account different conductivity distribution. For given object’s parameters, the minimum number of measuring points allowing successful reconstruction has been determined.

A simple test example has been proposed for MAT-MI forward problem. Analytical closed-form solutions have been used to check the validity of the made in-house finite element software. More complex forward and inverse problems have been solved using the software.

Looks at how the news media is making use of, and adapting to, the Web and whether any of the media has found a language that is better than traditional print. Recommends that the newspaper business has to reinvent itself right away or, in a short time, it could disappear for good.

The purpose of this paper is to emphasize on the need for a fair and just economic system to achieve sustainability.

Using systems thinking approach it shows that climate change, ecological degradation, population growth, poverty and the resource scarcity, the problems of failing financial markets and economic recession are all intertwined with the present economic system, which has been responsible for transgressing the balance of nature.

The paper shows that all the reforms or alternatives to the contemporary economic system proposed in the literature do not really address the root cause of all the problems, which is the built-in usurious system, made possible with the paper currency, in the economy that creates great injustices. The paper argues that solutions of science and technology to ecological problems are limited because of ecological shortsightedness and corporate greed.

The paper introduces the concept of “fair and just” economic system for sustainable development of humanity and suggests future directions for its realization.

Compares the features of the 1995 Boeing 777 with its predecessors, highlighting the increased use of digital technology. Emphasizes the much improved reliability of the on‐board maintenance system and describes the sophisticated built‐in fault reporting and test capabilities.

Movers & Shakers (M&S) is a project initiative relating to healthy ageing for older adults in Buckinghamshire. This early intervention well‐being programme aims to engage the mind, body and soul of participants by encouraging participation in physical, mental and creative activities and healthy eating initiatives. The Movers & Shakers programme can be adapted to create an individual ‘style’ to suit the specific needs of different communities. This article details how the Movers & Shakers programme has been adapted for use with Asian and Caribbean communities, combining the elements of the programme to create an environment of social inclusion for older people.