Investigation on the future of work: the impact of innovative strategies in a post pandemic scenario

In the following research work, an experiment of guided innovation is presented. The context is the Innovation for Change (I4C) program, in which a group of students, either PhDs or MBAs, are asked to solve a challenge provided by a stakeholder. The problem is “the future of work” in the context of a post pandemic scenario, with a focus on how to manage spaces remained empty due to remote working. The solution obtained is the consequence of a combination of brainstorming sessions, problem definition, benchmarking and interviewing stakeholders, experimental validation and prototyping. The outcome is a platform, B-Hub, which exploits empty locations to create a network of decentralised co-working spaces in which employees from every company can remotely work

Energy efficient design of regenerative shock absorbers for automotive suspensions: A multi-objective optimization framework

This study addresses the optimized design of electro-hydrostatic regenerative shock absorbers to enhance vibrational energy recovery in ground vehicles, aiming to reduce carbon footprint. The design strategy focuses on maximizing regeneration efficiency while minimizing actuator volume. Important trade-offs are considered as constraints, such as ride comfort and road holding. The approach employs a multi-objective evolutionary genetic algorithm, validated through numerical analysis, and applied to design a prototype. Experimental results show a peak regeneration efficiency of 45%, and simulations on a class-B vehicle indicate an average regenerated power of 101 W per shock absorber, corresponding to a CO2 emission reduction of 5.25 g/km

Comparison of multi-state Markov models for cancer progression with different procedures for parameters estimation. An application to breast cancer

Background: the knowledge of sojourn time (the duration of the preclinical screen-detectable period) and screening test sensitivity is crucial for understanding the disease progression and the effectiveness of screening programmes. For this purpose a model of the natural history of the disease is needed. The aim of this work is to provide an illustration of the application of multistate Markov models for breast cancer progression to the data of the Florentine screening programme, in order to estimate the sojourn time and sensitivity for breast cancer screening. Methods: three different multi-state Markov models of increasing complexity were used with three different estimation procedures based on non-linear least squares, maximum likelihood, and on a Bayesian approach. All the models produced estimates for screening sensitivity and mean sojourn time. The data used in our application seem to lead to a non-identifiability problem, since the estimation procedures for both the Maximum Likelihood and Non-Linear Least Squares gave estimates that changed with the parameters’ initial values or difficultly converged. In order to take this problem into account we used the Bayesian Approach by incorporating prior information on all the parameters. Results: the mean sojourn time varied between 2-7 years and 3-5 years for women aged 50-59 and 60-69, respectively. When the model complexity was increased a higher variability in estimates was observed among the estimation procedures. The results of the screening sensitivity estimates were highly variable, both among estimation techniques and models - varying between 63% and 100%, and between 77% and 100% for women aged 50-59 and 60-69, respectively. Conclusions: results are in accord with the literature; those obtained through the Bayesian Approach seem to be more reliable.&nbsp

Highly Compact Swing Assistive Knee Prosthesis Integrating Active and Passive Hydraulic Systems

This work proposes a novel partially powered knee prosthesis to give full support to swing related activities. It represents a technological step forward when compared to microprocessor-controlled knees. The device is based on the electro-hydrostatic actuation principle, combined with the use of a series rotary valve to aid during dissipative phases. Another key feature is the backdrivability enabled by a directly coupled fluid-based actuation principle. To this end, we present a compact design that is subsequently built and tested experimentally with an able-body adapter to simulate a real-case scenario of level walking and stair tasks. Results are compared with the features of existing commercial and research devices. To the best of the authors' knowledge, the proposed prosthesis is the most compact electro-hydrostatic swing assistive device with the potential to improve the walking gait, for instance by increasing toe clearance and likely reducing the occurrence of stumbling or falling events. Additionally, the prototype enables stair ascent in a step-over fashion, a capability generally unattainable with commercial microprocessor-controlled knees

Design and Optimization of an Active Leveling System Actuator for Lunar Lander Application

This work proposes a systematic methodology for designing an active leveling system (ALS) actuator for lunar landing application. The ALS actuator is integrated into an inverted tripod leg layout, exploiting a honeycomb crushable damper as a shock absorber. The proposed ALS actuator is fitted within the leg’s primary strut and features a custom permanent-magnet synchronous machine rigidly coupled with a lead screw. The actuator aims to both provide proper leg deployment functioning and compensate for the different shock absorber deformations during landing. The leg dynamic behavior is simulated through a parameterized multi-body model to investigate different landing scenarios. First, a parametric sensitivity approach is used to optimize the transmission system and the electric machine characteristics. Then, the electric motor model is numerically validated and optimized through electromagnetic finite element analysis. To validate the proposed ALS design methodology, a virtual test bench is used to assess the ALS performances under different load scenarios. It is found that the proposed methodology is able to yield a compact, well-sized actuator which is numerically validated with the EL3 platform as a case study

Cotas do tipo nordhaus-gaddum para o número de aniquilação / Sharp bounds for the annihilation number of the nordhaus-gaddum type

Seja  um grafo com  vértices e  seu complemento. O número de aniquilação de , denotado por , é o maior número inteiro  tal que a soma dos  menores graus de  não ultrapassa seu número de arestas. Esse invariante é usado como cota superior para o número de independência do grafo. Neste trabalho, apresentamos as seguintes cotas para o número de aniquilação e seu problema de Nordhaus-Gaddum Também investigamos o comportamento extremal desses invariantes e mostramos que satisfazem a propriedade do intervalo. Além disso, caracterizamos alguns grafos extremais, garantindo que as cotas obtidas são as melhores possíveis

Human-centered design trade-offs for semi-powered knee prostheses: A review

For many decades, developments of knee prostheses have shown a dichotomy regarding fundamental working principles. The industry has mainly emphasized on quasi-passive hydraulic solutions, whereas most research works have focused on powered devices, employing electric actuation. The former have an energetically passive effect at the knee joint, for which they often lack in providing versatility and movement robustness for the wearer. Powered prostheses can address these deficiencies, but are often rejected as they struggle to fulfill other user needs (e.g., weight and acoustic noise). Correspondingly, recent studies have emerged that attempt to significantly attenuate the deficiencies of fully powered prosthesis knees, partially sacrificing on device versatility. Recognizing the state-of-the art difficulties in balancing active assistance and user needs fulfilment, this work analyses human-centered design perspectives and their prospects for prosthetic development, in light of the often diverging user needs. We conclude that various types of both explored and yet unexplored semi-powered solutions may have the potential to provide the better trade-off between quasi-passive and fully powered prosthetic devices

breast screening axillary lymph node status of interval cancers by interval year

Abstract The aim of this study was to determine whether the excess risk of axillary lymph node metastases (N+) differs between interval breast cancers arising shortly after a negative mammography and those presenting later. In a registry-based series of pT1a–pT3 breast carcinoma patients aged 50–74years from the Italian screening programmes, the odds ratio (OR) for interval cancers ( n =791) versus the screen-detected (SD) cancers ( n =1211) having N+ was modelled using forward stepwise logistic regression analysis. The interscreening interval was divided into 1–12, 13–18, and 19–24months. The prevalence of N+ was 28% among SD cancers. With a prevalence of 38%, 42%, and 44%, the adjusted (demographics and N staging technique) OR of N+ for cancers diagnosed between 1–12, 13–18, and 19–24months of interval was 1.41 (95% confidence interval 1.06–1.87), 1.74 (1.31–2.31), and 1.91 (1.43–2.54), respectively. Histologic type, tumour grade, and tumour size were entered in turn into the model. Histologic type had modest effects. With adjustment for tumour grade, the ORs decreased to 1.23 (0.92–1.65), 1.58 (1.18–2.12), and 1.73 (1.29–2.32). Adjusting for tumour size decreased the ORs to 0.95 (0.70–1.29), 1.34 (0.99–1.81), and 1.37 (1.01–1.85). The strength of confounding by tumour size suggested that the excess risk of N+ for first-year interval cancers reflected only their higher chronological age, whereas the increased aggressiveness of second-year interval cancers was partly accounted for by intrinsic biological attributes