Wireless sensor networks (WSNs) enable new applications and require non-conventional paradigms for protocol design due to several constraints. Owing to the requirement for low device complexity ...together with low energy consumption (i.e., long network lifetime), a proper balance between communication and signal/data processing capabilities must be found. This motivates a huge effort in research activities, standardization process, and industrial investments on this field since the last decade. This survey paper aims at reporting an overview of WSNs technologies, main applications and standards, features in WSNs design, and evolutions. In particular, some peculiar applications, such as those based on environmental monitoring, are discussed and design strategies highlighted; a case study based on a real implementation is also reported. Trends and possible evolutions are traced. Emphasis is given to the IEEE 802.15.4 technology, which enables many applications of WSNs. Some example of performance characteristics of 802.15.4-based networks are shown and discussed as a function of the size of the WSN and the data type to be exchanged among nodes.
Professional education programs in environmental design disciplines aim to create ready-to-work designers to introduce in the world of practice. Studio courses are the places where students learn how ...to perform the professional tasks of design. Education in the studios has a practice-oriented focus, and students usually engage forms of experiential learning, focusing on the performance of final products rather than reflecting on the process. Forms of reflection on the design process do not seem to be part of the tradition of such courses. Students are not taught to do that, so this is also why they find difficult to convey what is in their mind when they are designing. The purpose of this talk is to start a discussion about the type of education instructors offer in design studio courses. In the text, I presents a qualitative research process where I have observed a course class in the Master program of Landscape Architecture at the Swedish University of Agricultural Sciences in Uppsala. Students’ voices captured during the final workshop in this course show how they reflect on their design process and how they perceive their design experience.
The ongoing 2020 coronavirus disease (COVID-19) pandemic is an enormous challenge for the health systems and the entire societies of the countries involved. Since at present the outbreak continues to ...evolve (April 2020), the World Health Organization (WHO) has declared it a public health emergency of international concern, specifying that public health interventions aimed at the prevention of the further spread of this disease include quarantine. Quarantine, that may be defined as a restraint on the activities of people or on the traffic of goods, targeted to the prevention of the diffusion of communicable pathologies, is a health concept profoundly rooted in the history of mankind. The lessons of the past are always pertinent for the present and for the future, in particular from a public health standpoint. One of the most relevant of them is connected with previous influenza pandemics, similar to the current COVID-19 2019/2020 pandemic, and it indicates that it is practically impossible, even in recent times, to contain the infection in the geographic area where it has risen and to prevent its trans-national disseminated spread. With specific reference to the COVID-19 pandemic, therefore, health authorities still adopt "classical" preventive interventions, namely workplace social distancing measures and quarantine, to reduce the transmission of the disease. Only the future will testify the precise overall effectiveness of preventive public health measures in containing the impact of the present coronavirus pandemic. However, what in this epidemiological scenario is already known, is that the multi-century international health value of quarantine remains essential and unavoidable.
Network Experimentation for Cooperative Localization Conti, A.; Guerra, M.; Dardari, D. ...
IEEE journal on selected areas in communications,
2012-February, 2012-02-00, Letnik:
30, Številka:
2
Journal Article
Recenzirano
This paper introduces the notion of network experimentation and proposes an experimentation methodology particularly suited for cooperative wireless networks. Based on this methodology we performed ...extensive measurement campaigns and compare various cooperative localization techniques under a common setting. Network experiments enable (i) the quantification of cooperation benefits, (ii) the development of techniques for harnessing environmental information, and (iii) the characterization of network localization algorithms. As a case study, we consider ultrawide bandwidth cooperative location-aware networks in cluttered indoor environments and evaluate their performance based on measurements collected from network experiments.
A
bstract
We present general results on generating AdS
2
solutions to Type II supergravity from AdS
3
solutions via U(1) and SL(2) T-dualities. We focus on a class of Type IIB solutions with small 𝒩 ...= 4 supersymmetry, that we show can be embedded into a more general class of solutions obtained by double analytical continuation from AdS
3
geometries with small 𝒩 = (0, 4) supersymmetry constructed in the literature. We then start the analysis of the superconformal quantum mechanics dual to the 𝒩 = 4 backgrounds focusing on a subclass of AdS
2
× S
3
× 𝕋
3
solutions foliated over a Riemann surface. We show that the associated supersymmetric quantum mechanics describes monopole bubbling in 4d 𝒩 = 2 supersymmetric gauge theories living in D3-D7 branes, as previously discussed in the literature. Therefore, we propose that our solutions provide a geometrical description via holography of monopole bubbling in 4d 𝒩 = 2 SCFTs. We check our proposal with the computation of the central charge.
Muscovite mica, KAl
(Si
Al)O
(OH)
, is a common layered phyllosilicate with perfect cleavage planes. The atomically flat surfaces obtained through cleaving lend themselves to scanning probe ...techniques with atomic resolution and are ideal to model minerals and clays. Despite the importance of the cleaved mica surfaces, several questions remain unresolved. It is established that K
ions decorate the cleaved surface, but their intrinsic ordering - unaffected by the interaction with the environment - is not known. This work presents clear images of the K
distribution of cleaved mica obtained with low-temperature non-contact atomic force microscopy (AFM) under ultra-high vacuum (UHV) conditions. The data unveil the presence of short-range ordering, contrasting previous assumptions of random or fully ordered distributions. Density functional theory (DFT) calculations and Monte Carlo simulations show that the substitutional subsurface Al
ions have an important role for the surface K
ion arrangement.
When choosing the technology options to develop a wireless sensor network (WSN), it is vital that their performance levels can be assessed for the type of application intended. This book describes ...the different technology options – MAC protocols, routing protocols, localisation and data fusion techniques – and provides the means to numerically measure their performance, whether by simulation, mathematical models or experimental test beds. Case studies, based on the authors’ direct experience of implementing wireless sensor networks, describe the design methodology and the type of measurements used, together with samples of the performance measurements attained.
Anatomy constitutes the historical and epistemological background of surgery and surgery, in turn, is the area of medicine dealing with the management of injuries and pathologies by means of manual ...interventions and instrumental devices. As such, surgery may be considered as old as mankind. However, only in the Age of Enlightenment (eighteenth century) was the rigid and negative distinction typical of the past between clinical medicine and surgery overcome. This historical differentiation is by many historians of Western medicine ascribed to the famous Hippocratic Oath, a deontological text attributed to the Hippocratic School (V-IV centuries B.C.). The object of this contribution is the description of the evolution of surgery in the course of the Middle Ages and the Renaissance, periods in which a number of fundamental acquisitions in surgical practice were gained, ranging from a more correct treatment of wounds and lesions to the elaboration of the first effective methods for vessel ligature, from the improvement of amputation techniques to the refinement of trauma surgery, from the major progress in human anatomical knowledge to the invention of new surgical devices, including the obstetrical forceps. Last but not least, the achievement on the part of surgeons of a more codified professional role, their acquisition of a more honourable deontological profile and the definition of their clearer collocation in the sanitary panorama, appear as paramount historical-epistemological achievements typical of the surgery practiced during the Middle Ages and the Renaissance. Keywords Anatomy, surgery, history of medicine, middle ages, renaissance, therapy.
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