554 research outputs found
ACCUMULATED FATIGUE AFFECTS RUNNING BIOMECHANICS DEPENDING ON THE PERFORMANCE LEVEL DURING A TRIATHLON COMPETITION
The purposes of the present study were 1) to examine the different responses to the accumulated fatigue between international and national level triathletes in competition, and 2) to compare the profile of the running part presented by the two different performance levels. 32 participants at Madrid 2008 Triathlon World Cup and 32 participants at Spanish National Championships 2008, made up the sample. We found higher values (
Systems Engineering and Its Application to Industrial Product Development
PREFACE : Mastering the complexity of innovative systems currently looks a challenging goal of design and product development as well as embedding a suitable degree of smartness in devices, machines and equipment to make them able of adapting their operation to variable conditions or effects of a harsh environment. This goal is achieved through a continuous monitoring of the system in service, an effec-tive control of its behavior and a wide connectivity towards many other systems. Only an effective system design and manufacture, able to cover all the required actions, can assure this kind of assessment overall the life cycle since a very ear-ly concept of the product to a full disposal and service.
Complexity makes hard managing the product development, because of the number of functions, subsystems, components and related interfaces usually in-volved, like in motor vehicles, robots, railways systems, aircrafts and spacecrafts as well as in large industrial manufacturing systems or very innovative microsys-tems and bioinspired devices. A crucial issue in this activity is performing a bright and complete elicitation of requirements, which need to be fully and suit-ably allocated to the system components, through a clear traceability, especially in systems produced as a result of material processing and assembling of parts. Moreover, the product must fit the requirements associated to some customer needs, innovation targets, and technical standards and be compatible with the manufacturer’s capabilities.
As it looks clear from the current state–of–art, since several years the Systems Engineering assures a suitable answer to the needs above mentioned. It provides a methodology to drive the product lifecycle assessment that is implemented through a well defined process, being based on some specific and graphical lan-guages and even formalized in several tools enabling the required analyses, tak-ing advantage of the capabilities of some dedicated commercial software. Those contents lead to create a platform, consisting of a sort of tools chain, which might be used and shared among different industrial and professional partners to digitalize both the information and even the whole industrial product develop-ment, as far as the current strategy referred to as “Industry 4.0 / The Factory of the Future” brightly suggests and supports. The so–called Model Based Systems Engineering (MBSE) is then successfully proposing an effective and modern al-ternative to the document-based approach, using data models as a main element of the design process. Some technical standards already drive the user in imple-menting the Systems Engineering, thus leading to develop a systematic approach the design aimed at satisfying the customer needs. Suitable capabilities in the manufactured system are assured by the so–called architectural frameworks, which support the system development and integration.
The Model Based Systems Engineering allows proceeding with a modeling activity which investigates requirements, behavior and architecture through a combined operational, functional and logical analysis, being linked and interop-erated with a mathematical and physical modeling, which is typically more known and widely used within the industrial engineering. A full integration of all the activities of the Product Lifecycle Management (PLM) is currently going on, to include the system architecture definition and its Application Lifecycle Man-agement (ALM) as well as the Product Data Management (PDM), i.e. the design activity together with the tasks of production, testing, homologation and service. A recognized standard certification to qualify the Systems Engineer is even available as the International Council on Systems Engineering (INCOSE) pro-vides.
The scenario above described is strongly integrated with the increasing devel-opment of both the network and the cyber–physical systems, for a fully distribut-ed connectivity, to be exploited in advanced smart systems and devices as well as in intelligent manufacturing, according to the most recent strategies of innova-tion as the “Industry 4.0” initiative and the “Lean manufacturing” idea. Simulta-neously, the system smartness and connectivity together increase the demand of data transmission and elaboration, thus linking this topic to the technology of big data management, whilst they benefit of the progress in information technology, through a secure cloud based on the network.
The context just described motivates the fast diffusion of the Model Based Systems Engineering as a tool for innovating all the production processes. The increasing demand of specialized software and of educational activities as well as the number of workshops and conferences focused on this topic confirm this trend. However, it might be remarked that several contributions to the literature about the Systems Engineering widely grew up during the last years, thus making the Reader sometimes confused, especially when approaching this topic at first.
The Systems Engineering topics are so many that it looks rather difficult mas-tering its skills, without a preliminary classification of contents. Technical do-mains involved are mainly those of engineering and computer science, although many other ones play the role of a daily user of this methodology. According to the most recent development of the Systems Engineering, whose typical applica-tion fields were the software and electronic systems even for space missions, the current focus consists of several industrial systems, being gradually innovated by introducing the tailored solutions of mechatronics. It is worthy noticing that a significant advancement was introduced between the very early implementation of the Systems Engineering and its recent evolution, since several new applica-tions are focused on the production of systems, which need to be manufactured through a material processing. Usually, they exhibit some attributes related both to their physical nature and to the functions performed, thus requiring to model both their functional and physical behaviors together. This need is changing the scenario of the typical applications of the Systems Engineering as software de-sign.
This handbook expressively avoids to cover all the typical contents of the spe-cialized literature of the Model Based Systems Engineering, whilst is aimed at making easier a first approach to this topic and sharing a preliminary experience performed by the authors within some industrial domains, by proceeding in the modeling activity in a real industrial environment. The main goal is drawing a sort of simple and hopefully clear roadmap in modeling and developing the in-dustrial and material systems and in implementing the Systems Engineering, par-ticularly in the design activity. Therefore, the target audience of this handbook includes professional engineers, scientists and students dealing with the Applica-tion Lifecycle Management and the system architecture assessment, more than the Product Data Management or the whole Product Lifecycle Management.
The approach followed is that of introducing some examples of implementa-tion of the Systems Engineering, by proceeding step by step from the screening of needs and the elicitation of requirements till a synthesis of the system design. Each action will be referred to the literature, related to the implementation of the Systems Modeling Language or SysML and to the use of some tools available on market, thus highlighting benefits, drawbacks and current limitations of some dedicated software or even of some proposed methodologies. Several comments will be provided to describe the troubles shared among some users of the Sys-tems Engineering as they were detected in daily practice by the authors. They wish that this handbook could briefly and gradually provide the Reader with a preliminary guideline to approach professionally the Model Based Systems En-gineering, by understanding its main contents and applying it to the industrial environment. As a desired result, this work might be considered as an integration of some textbooks of Machine Design, and it is aimed at completing the education within Engineering Design or at simply providing a friendly introduction to the Systems Engineerin
Cluster of legionnaires’ disease in an Italian prison
Background: Legionella pneumophila (Lp) is the most common etiologic agent causing Legionnaires’ Disease (LD). Water systems offer the best growth conditions for Lp and support its spread by producing aerosols. From 2015 to 2017, the Regional Reference Laboratory of Clinical and Environmental Surveillance of Legionellosis of Palermo monitored the presence of Lp in nine prisons in Western Sicily. During this investigation, we compared Lp isolates from environmental samples in a prison located in Palermo with isolates from two prisoners in the same prison. Methods: We collected 93 water samples from nine Sicilian prisons and the bronchoalveolar lavages (BALs) of two prisoners considered cases of LD. These samples were processed following the procedures described in the Italian Guidelines for the Prevention and Control of Legionellosis of 2015. Then, genotyping was performed on 19 Lp colonies (17 from water samples and 2 from clinical samples) using the Sequence-Based Typing (SBT) method, according to European Study Group for Legionella Infections (ESGLI) protocols. Results: Lp serogroup (sg) 6 was the most prevalent serogroup isolated from the prisons analyzed (40%), followed by Lp sg 1 (16%). Most of all, in four penitentiary institutions, we detected a high concentration of Lp >104 Colony Forming Unit/Liter (CFU/L). The environmental molecular investigation found the following Sequence Types (STs) in Lp sg 6: ST 93, ST 292, ST 461, ST 728, ST 1317 and ST 1362, while most of the isolates in sg 1 belonged to ST 1. We also found a new ST that has since been assigned the number 2451 in the ESGLI-SBT database. From the several Lp sg 1 colonies isolated from the two BALs, we identified ST 2451. Conclusions: In this article, we described the results obtained from environmental and epidemiological investigations of Lp isolated from prisons in Western Sicily. Furthermore, we reported the first cluster of Legionnaires’ in an Italian prison and the molecular typing of Lp sg 1 from one prison’s water system and two BALs, identified the source of the contamination, and discovered a new ST
The impact of prescription pain reliever misuse and heroin use on morbidity and mortality by level of urbanicity: 2002-2014
Non-medical use of prescription pain relievers (PPRs), heroin, and more recently fentanyl, continue to have major public health consequences in the United States. This article analyzes trends in PPR and heroin use, emergency department and hospital stays, substance use treatment services, and mortality to assess the relative impact of the opioid crisis on rural versus more urbanized counties in the United States. Our findings suggest that while more urbanized counties have had greater increases in opioid use, rural and less urbanized counties tended to be more negatively impacted than larger and non-rural counties. Disparities in service availability highlight the need for a serious discussion on how resources are allocated in counties that have lower tax bases. Based on these results, we conclude that rural and less urbanized counties can benefit from real increases in resources for substance use prevention and treatment services, including the expansion of prescribers trained to screen and treat opioid use. Understanding the unique challenges of rural and less urbanized counties may help decrease the disparity in consequences found in this study
Induction of IL-8 production by Helicobacter pylori strains with different cagA genotype and oipA functional status.
Horizontes de fragipan de tipo «ison» formados por permafrost en la Sierra de Guadarrama
A toposecuence of soiIs that incIudes soils with fragipan of ison sort (FitzPatrick, 1974) is studied in the Sierra de Guadarrama. The presence of these soils in the high part of the mountain confirms the permafrost formation in the last glaciation. On the other band, the analitical data and tbe field observations of soils allow us to stablish, hypoteticaIIy, three stages in their evolution: 1) prewürm weathering and pedogenesis; 2) compaction and densification of the soils mass in the area affected by the permafrost; 3) truncation, fosilization and pedogenesis phenomena in the Holocene. About the climate the mean annual temperature in the last cold period must have been between 7,5 ºC and 12,5 ºC lower than now.Se estudia en la Sierra de Guadarrama una toposecuencia edáfica que incluye suelos con fragipan de tipo, «ison» (Fitz Patrick, 1974). La presencia de estos suelos en la parte alta de la sierra confirma la formación de permafrost en el último período frío. Además, los datos analíticos y las observaciones de campo permiten establecer, hipotéticamente, tres etapas en la evolución de los suelos: 1) alteración y edafización anterior al período frío; 2) compactación y densificación de la masa del suelo en las zonas afectadas por permafrost; 3) fenómenos de truncamiento, fosilización y edafización en el Holoceno. En cuanto al clima se concluye que la temperatura media anual en el último período frío debió ser entre 7,5 ºC y 12,5 ºC inferior a la actual
Dificultades en el aprendizaje, inclusión cultural y autoexpectativas académicas: una propuesta de orientación e intervención educativa
Auto-ecology of the Queen Conch (Strombus gigas L. 1758) at Cabo Cruz, Eastern Cuba: Management and Sustainable Use Implications
- …