A genetic algorithm-assisted semi-adaptive MMSE multi-user detection for MC-CDMA mobile communication systems

In this work, a novel Minimum-Mean Squared-Error (MMSE) multi-user detector is proposed for MC-CDMA transmission systems working over mobile radio channels characterized by time-varying multipath fading. The proposed MUD algorithm is based on a Genetic Algorithm (GA)-assisted per-carrier MMSE criterion. The GA block works in two successive steps: a training-aided step aimed at computing the optimal receiver weights using a very short training sequence, and a decision-directed step aimed at dynamically updating the weights vector during a channel coherence period. Numerical results evidenced BER performances almost coincident with ones yielded by ideal MMSE-MUD based on the perfect knowledge of channel impulse response. The proposed GA-assisted MMSE-MUD clearly outperforms state-of-the-art adaptive MMSE receivers based on deterministic gradient algorithms, especially for high number of transmitting users

Improved microwave imaging procedure for non-destructive evaluations of two-dimensional structures

Improved microwave imaging procedure for nondestructive evaluations of two dimensional structures Author(s): Caorsi, S (Caorsi, S); Massa, A (Massa, A); Pastorino, M (Pastorino, M); Donelli, M (Donelli, M) Source: IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION Volume: 52 Issue: 6 Pages: 1386-1397 DOI: 10.1109/TAP.2004.830254 Published: JUN 2004 Times Cited: 31 (from Web of Science) Cited References: 23 [ view related records ] Citation Map Abstract: An improved microwave procedure for detecting defects in dielectric structures is proposed. The procedure is based on the integral equations of the inverse scattering problem. A hybrid genetic algorithm (GA) is applied in order to minimize the obtained nonlinear functional. Since in nondestructive evaluations the unperturbed object is completely known, it is possible off-line to numerically compute the. Green's function for the configuration without defects. Consequently, a very significant computation saving is obtained, since the "chromosome" of the GA codes only the parameters describing the unknown defect. Accession Number: WOS:000221857300001 Document Type: Article Language: English Author Keywords: genetic algorithms (GAs); Green's function; microwave imaging; nondestructive evaluation (NDE) KeyWords Plus: GENETIC ALGORITHM; ELECTROMAGNETICS; RECONSTRUCTION Reprint Address: Caorsi, S (reprint author), Univ Pavia, Dept Elect, Via Palestro 3, I-27100 Pavia, Italy Addresses: 1. Univ Pavia, Dept Elect, I-27100 Pavia, Italy E-mail Address: [email protected] Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 445 HOES LANE, PISCATAWAY, NJ 08855 USA Web of Science Category: Engineering, Electrical & Electronic; Telecommunications Subject Category: Engineering; Telecommunications IDS Number: 826VJ ISSN: 0018-926

Effect of Progressive Integration of On-Board Systems Design Discipline in an MDA Framework for Aircraft Design with Different Level of Systems Electrification

The on-board design discipline is sometimes ignored during the first aircraft design iterations. It might be understandable when a single on-board system architecture is considered, especially when a conventional architecture is selected. However, seeing the trend towards systems electrification, multiple architectures can be defined and each one should be evaluated during the first tradeoff studies. In this way, the systems design discipline should be integrated from the first design iterations. This paper deals with a progressive integration of the discipline to examine the partial or total effect of the systems design inside an MDA workflow. The study is carried out from a systems design perspective, analyzing the effect of electrification on aircraft design, with different MDA workflow arrangements. Starting from a non-iterative systems design, other disciplines such as aircraft performance, engine design, and aircraft synthesis are gradually added, increasing the sensibility of the aircraft design to the different systems architectures. The results show an error of 40% in on-board systems assessment when the discipline is not fully integrated. Finally, using the work-flow which allows for greater integration, interesting differences can be noted when comparing systems with different levels of electrification. A possible mass saving of 2.6% of aircraft MTOM can be reached by properly selecting the systems technologies used

Clinical efficacy of medical hydrology: an umbrella review

The aim of this research was to summarize available scientific evidence on the efficacy of medical hydrology for the management of any health condition. The search was conducted on 26th March 2021, in the following databases: Medline (via PubMed), EMBASE, Web of Science, Cochrane Library, and Google Scholar. All relevant literature reviews investigating the clinical efficacy of interventions characterized by the use of natural mineral waters and muds were included. The quality of studies was assessed with the “AMSTAR 2” tool. After article screening, 49 reviews were included in this work. Overall, retrieved scientific evidence suggests that spa therapy is beneficial for patients affected by some specific musculoskeletal conditions, with improvements potentially lasting up to 9 months. Moreover, balneotherapy can be an integrative support for the management of chronic venous insufficiency and some inflammatory skin diseases like psoriasis. The role of spa therapy in rehabilitation appears relevant as well. More limited, although interesting evidence exists for inhalation and hydropinic therapies. Globally, retrieved evidence suggests that, besides individual wellbeing, medical hydrology can be useful for public health. In particular, higher-quality studies seem to support the integrative use of spa-related interventions for conditions like osteoarthritis, fibromyalgia, low back pain of rheumatic origin, and chronic venous insufficiency. However, the body of evidence has some limitations and further clinical trials should be designed for each relevant application to consolidate and expand acquired knowledge

Disruptive crisis management: lessons from managing a hospital during the COVID-19 pandemic

Purpose: Healthcare organizations worldwide were badly hit by the “surprise” of the pandemic. Hospitals in particular are trying hard to manage problems it caused, searching for solutions to protect the health of citizens and reorienting operations. The implementation of resilience solutions in the coping phase and the ability to react promptly and redefine activities is essential. Integrating crisis management and resiliency literature, this paper discusses how health organizations were able to cope with adversity during the crisis. Design/methodology/approach: The research is conducted through a case study of a large Italian hospital, the Gemelli Polyclinic Foundation, which was one of the leading hospitals in the Italian response to the pandemic. Findings: The case reports actions taken in order to continue functioning and to maintain core activities despite severe adversity. The overall response of the Gemelli was the result of the three types of response: behavioral (effective leadership), cognitive (rapid resource reallocation) and the contextual reinforcement (multiagency network response). The authors highlight how an integrative framework of crisis management and resiliency could be applied to healthcare organizations in the coping phase of the pandemic. The experience of the Gemelli can thus be useful for other hospitals and organizations facing external crises and for overall improvement of crisis management and resilience. Responding to crisis brings the opportunity to make innovations introduced during emergencies structural, and embed them moving forward. Research limitations/implications: The paper focuses only on the coping phase of the response to the pandemic, whereas building long-term resilience requires understanding how organizations accumulate knowledge from crises and adapt to the “new normal.” Originality/value: The paper responds to the call for empirical studies to advance knowledge of an integrative framework of crisis management and resiliency theories with reference to complex organizations such as healthcare

Assessing the Integration of Electrified On-Board Systems in an MDAO framework for a small transport aircraft

The integration of on-board systems design within the aircraft design process is often considered only in the late part of the initial design. This is acceptable for civil aircraft using standard technology systems. However, facing with MEA and AEA concepts and different possible architectures, the systems design and the assessment of their effects on the overall aircraft should be moved up in the usual design process. This paper deals with evaluation of the effect of different on-board systems architecture, with a different electrification level, on the overall aircraft design. These effects have been evaluated using three different MDA workflows developed within the AGILE4.0 European research project. The workflows are defined with an increasing number of disciplines to show how the effect of a proper selection of a systems architecture is differently caught by each one. In this way it is possible to define which disciplines should be included for the systems architecture assessment. The results show a save of 1% of MTOM for the AEA applied to a small turboprop aircraft when only the OBS mass is assessed. Increasing workflow complexity, adding performance and engine design the save increase to 1.2%. Finally, the save increases to 1.3% when the effect on engine SFC is also considered

Poloxamer 338 affects cell adhesion and biofilm formation in escherichia coli: Potential applications in the management of catheter-associated urinary tract infections

Poloxamers are nontoxic, amphiphilic copolymers used in different formulations. Due to its surfactant properties, Poloxamer 338 (P388) is herein proposed as a strategy to avoid biofilm formation often causing recalcitrant catheter-associated urinary tract infections (CAUTI). The aim is to evaluate the ability of P388 coatings to affect the adhesion of Ec5FSL and Ec9FSL Escherichia coli strains on silicone urinary catheters. Attenuated total reflection infrared spectroscopy, atomic force microscopy, and static water contact angle measurement were employed to characterize the P388-coated silicone catheter in terms of amount of P388 layered, coating thickness, homogeneity, and hydrophilicity. In static conditions, the antifouling power of P388 was defined by comparing the E. coli cells adherent on a hydrophilic P388-adsorbed catheter segment with those on an uncoated one. A P388-coated catheter, having a homogeneous coverage of 35 nm in thickness, reduced of 0.83 log10 and 0.51 log10 the biofilm of Ec5FSL and Ec9FSL, respectively. In dynamic conditions, the percentage of cell adhesion on P388-adsorbed silicone channels was investigated by a microfluidic system, simulating the in vivo conditions of catheterized patients. As a result, both E. coli isolates were undetected. The strong and stable antifouling property against E. coli biofilm lead us to consider P388 as a promising anti-biofilm agent for CAUTIs control

Value-based health-care principles in health-care organizations

Purpose: This study aims to analyze the value-based health-care model in defining a strategy to guide the evolution of health-care organizations toward a value-oriented model. To improve the quality of care by ensuring economic sustainability, it is necessary to redefine the concept of competition in healthcare and align it with the concept of maximizing value for patients. Design/methodology/approach: Performance measurement is a crucial aspect of the analysis of health-care organizations. Porter developed an effective analytical technique and presented the measurement of health-care outcomes based on health conditions, the efficiency of health-care organizations and the type of service provided. Findings: Clinical outcomes and data on the costs of care of each patient are essential to evaluate improvement in treatment value over time. Engaging in the evaluation of what happens to patients in their course of care enables the expansion of the measurement of outcomes because it measures all the health services related to it. Originality/value: Building a health-care system based on the value and continuous improvement of care and services provided is a goal shared by many countries and international organizations. Today, the analysis of outcomes is important for making informed decisions, directing and planning clinical and organizational changes by improving the quality of care and services

A model-based rams estimation methodology for innovative aircraft on-board systems supporting mdo applications

The reduction of aircraft operating costs is one of the most important objectives addressed by aeronautical manufactures and research centers in the last decades. In order to reach this objective, one of the current ways is to develop innovative on-board system architectures, which can bring to lower fuel and maintenance costs. The development and optimization of these new aircraft on-board systems can be addressed through a Multidisciplinary Design Optimization (MDO) approach, which involves different disciplines. One relevant discipline in this MDO problem is Reliability, Availability, Maintainability and Safety (RAMS), which allows the assessment of the reliability and safety of aircraft systems. Indeed the development of innovative systems cannot comply with only performance requirements, but also with reliability and safety constraints. Therefore, the RAMS discipline plays an important role in the development of innovative on-board systems. In the last years, different RAMS models and methods have been defined, considering both conventional and innovative architectures. However, most of them rely on a document-based approach, which makes difficult and time consuming the use of information gained through their analysis to improve system architectures. On the contrary, a model-based approach would make easier and more accessible the study of systems reliability and safety, as explained in several studies. Model Based Systems Engineering (MBSE) is an emerging approach that is mainly used for the design of complex systems. However, only a few studies propose this approach for the evaluation of system safety and reliability. The aim of this paper is therefore to propose a MBSE approach for model-based RAMS evaluations. The paper demonstrates that RAMS models can be developed to quickly and more effectively assess the reliability and safety of conventional and innovative on-board system architectures. In addition, further activities for the integration of the model-based RAMS methodology within MDO processes are described in the paper