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Military hardware and technology transfer is increasingly becoming a crucial factor in international relations. This is especially so when the military hardware transfer involves sophisticated weap...

Ski boots are known to cause vasoconstriction in the wearer’s lower limbs and, thus, cause a “cold leg” phenomenon. To address this problem, this work provides a computational framework for analysing interactions between the ski boot and the lower limb. The geometry of the lower limb was derived from magnetic resonance imaging and computed tomography techniques and anthropometric data. The geometry of the ski boot shell was obtained by means of three-dimensional computer aided design models from a manufacturer. Concerning the ski boot liner, laser scanning techniques were implemented to capture the geometry of each layer. The mechanical models of the ski boot and the lower limb were identified and validated by means of coupled experimental investigations and computational analyses. The computational models were exploited to simulate the buckling process and to investigate interaction phenomena between the boot and the lower limb. Similarly, experimental activities were performed to further analyse the buckling phenomena. The obtained computational and experimental results were compared regarding both interaction pressure and displacements between the buckle and the corresponding buckle hooks. These comparisons provided reasonable agreement (mean value of discrepancy between the model and mean experimental results in the tibial region: 20%), underlining the model’s capability to correctly interpret results from experimental measurements. Results identified the critical areas of the leg, such as the tibial region, the calcaneal region of the foot and the anterior sole, which may suffer the most due to the hydrostatic pressure and compressive strain exerted on them. The results highlight that computational methods allow investigation of the interaction phenomena between the lower leg and ski boot, potentially providing an effective framework for a more comfortable and ergonomic design of ski boots.

In this paper the authors present the results of a dosimetric analysis related to the exposure of live-line workers to the magnetic fields generated by high voltage overhead lines and substations. The study extends the work published by Dawson et al. in 2002, considering more evolved anatomical models nowadays available, the new reference limits given by the 2013/35/EU Directive, and a new methodology, based on the intercomparison of two alternative solvers and the use of data filtering. Moreover, additional exposure scenarios are here considered with respect to the studies already available in literature. The results show that for the exposure scenario of high voltage live line works with bare hand method, in any analyzed position, the exposure limits for the tissues of the central nervous system, as well as for all other tissues, are never exceeded, despite in some cases the action levels are exceeded. For the exposure of workers in substations near 220 kV and 380 kV line trap coils exposure is compliant with the regulatory limits if the current flowing through the line trap does not exceed the value of 1000 A. Finally, for the exposure of workers in substations near cable connections, electric field values induced in the body are always lower than regulatory limits with a phase current value equal to 1600 A r.m.s.

Uncertainty propagation in a phaseless magnetic resonance-based electric properties tomography technique is investigated using the Monte Carlo method. The studied inverse method, which recovers the electric properties distribution at radiofrequency inside a scatterer irradiated by the coils of a magnetic resonance imaging scanner, is based on the contrast source inversion technique adapted to process phaseless input data., Comment: 4 pages, 6 figures. 2019 International Conference on Electromagnetics in Advanced Applications (ICEAA)

The Belt and Road Initiative (BRI) launched by President Xi Jinping in 2013, which is intended to promote economic development and exchanges between China and more than 60 countries, is gaining momentum. The BRI is not immune, however, to a number of important risks that in many instances are new to Chinese companies operating abroad. One oversight that must be addressed is that the BRI requires a wide range of security considerations along both the maritime and land routes. While the security problem has not gone unnoticed in Beijing, the solutions could be found elsewhere, namely in international companies that provide armed private security, special risk assessment, insurance and, perhaps most importantly, crisis mitigation.

This work analyses the thermal effects produced by the time-varying magnetic fields of a Magnetic Resonance Imaging scanner in the patient's body, also considering the case of a metallic implant. The computations are performed by the successive solution of an electromagnetic field and a thermal problem. In particular, the performances of a transient thermal solver, implemented according to the Douglas-Gunn scheme, are discussed and compared with other computational procedures. An example of application is finally presented.

Human resources management (HRM) in China requires a different approach from the ones commonly implemented in Europe or the United States. For the casual observer, what stands out are the difficulties that Chinese workers are accustomed to facing, such as overtime work, extreme working conditions due to hazardous materials, a lack of safety regulations, and an increasing unemployment rate in low technology energy-intensive industrial sectors that is casting a shadow over the near future. The Western media tends to focus on the negative consequences such as environmental and social degradation after three decades of China’s so-called ‘economic miracle’ accompanied by double-digit GDP growth. However, it is imperative to contextualize these and other related issued within the country as a whole. While China has been evolving at breakneck speed, this fast-changing process has led to China becoming the ‘world’s factory’, it was able to reinvent itself during past and current global economic and financial crisis. This chapter introduces some case studies of Italian businesses operating in China, analyzing different phases of HRM, starting from the past financial and production crises that have led to the bankruptcy of thousands of small and medium—sized companies to the most recent collapse of Chinese stock markets. The analysis will take account of the different categories of Chinese companies such as state-owned companies (SOEs), companies that operate with other companies through joint ventures and wholly foreign owned enterprises. China’s historical and cultural background and cultural information too are considered in order avoid a mere Western interpretations of phenomena and realities that need to be understood in a local context.

This paper investigates the uncertainty propagation in magnetic resonance-based electric properties tomography, a quantitative imaging technique that recovers the electric properties distribution inside a human body at the Larmor frequency. This is a needed step in order to make the quantitative results reliable for in vivo applications. To this aim, the contrast source inversion method is investigated as a promising technique and the uncertainty propagation through the corresponding model is studied by means of the Monte Carlo method. Thanks to the increased quality in the recovered electric properties, the results suggest that TEM coils for parallel transmission could be a preferable choice.

This paper investigates the effect of relevant physical parameters on transient temperature elevation induced in human tissues by electromagnetic waves in the terahertz (THz) band. The problem is defined by assuming a plane wave, which, during a limited time interval, normally impinges on the surface of a 3-layer model of the human body, causing a thermal transient. The electromagnetic equations are solved analytically, while the thermal ones are handled according to the finite element method. A parametric analysis is performed with the aim of identifying the contribution of each parameter, showing that the properties of the first skin layer (except blood flow) play a major role in the computation of the maximum temperature rise for the considered exposure situation. Final results, obtained by combining all relevant parameters together, show that the deviation from the reference solution of the maximum temperature elevation in skin is included in the coverage intervals from −30% to +10% at 0.1 THz and from −33% to +18% at 1 THz (with 95% confidence level). These data allow bounding the possible temperature increase against the spread of tissue properties that could be reasonably used for dosimetric simulations. Bioelectromagnetics. 35:314–323, 2014. © 2014 Wiley Periodicals, Inc.

The paper investigates the heating of tissues exposed to millimeter and sub-millimeter electromagnetic waves. The problem is faced by assuming a plane wave normally incident to the surface of a layered model of the human body and by solving analytically both the electromagnetic and thermal equations. The effect of a possible variability in the relevant parameters is put in evidence through a specific parametric analysis.