306 research outputs found
Push & Pull: autonomous deployment of mobile sensors for a complete coverage
Mobile sensor networks are important for several strategic applications
devoted to monitoring critical areas. In such hostile scenarios, sensors cannot
be deployed manually and are either sent from a safe location or dropped from
an aircraft. Mobile devices permit a dynamic deployment reconfiguration that
improves the coverage in terms of completeness and uniformity.
In this paper we propose a distributed algorithm for the autonomous
deployment of mobile sensors called Push&Pull. According to our proposal,
movement decisions are made by each sensor on the basis of locally available
information and do not require any prior knowledge of the operating conditions
or any manual tuning of key parameters.
We formally prove that, when a sufficient number of sensors are available,
our approach guarantees a complete and uniform coverage. Furthermore, we
demonstrate that the algorithm execution always terminates preventing movement
oscillations.
Numerous simulations show that our algorithm reaches a complete coverage
within reasonable time with moderate energy consumption, even when the target
area has irregular shapes. Performance comparisons between Push&Pull and one of
the most acknowledged algorithms show how the former one can efficiently reach
a more uniform and complete coverage under a wide range of working scenarios.Comment: Technical Report. This paper has been published on Wireless Networks,
Springer. Animations and the complete code of the proposed algorithm are
available for download at the address:
http://www.dsi.uniroma1.it/~novella/mobile_sensors
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Disintegration, modularity and entry mode choice: Mirroring technical and organizational architectures in business functions offshoring
We study the relationship between modularity and entry mode choice in the context of business functions offshoring. We define the degree of modularity of an activity as technical architecture (whether it can be detached from the rest of the value chain without loss of synergies). We refer to the entry mode chosen as organizational architecture (whether a captive solution, a partnership or outsourcing). We propose that the selection of entry mode should reflect the alignment of the technical and organizational architectures: that is, they need to be âmirroredâ. Modular activities are more likely to be outsourced, as modularity decreases transaction costs and knowledge leakages risks, while not-modular activities reflect captive entry modes. Based on the analysis of 486 business function offshoring initiatives, we also argue that firms can âbreakâ the mirror as the entry choice is contingent upon the level of disintegration of the value chain and the offshoring experience of the firms
The complementarity effect of exporting, importing and R&D on the productivity of Ukrainian MNEs
After two decades of research on Emerging Market Multinational Enterprises (EMNE), the debate still concerns the antecedents and strategies of their foreign expansion. However, much less has been said on the effects of international participation on their productivity. Building on insights from the Resource-Based View of the firm and agency theory, we develop hypotheses on the presence of complementarities among export, import and R&D and their impact on productivity. Our empirical analyses on a panel of 23,000 time-year observations of Ukrainian MNEs over the period 2000â2006, confirm that: (i) EMNEs benefit from complementarities stemming from the assimilation and integration of knowledge from international external sources (import and export) with internal knowledge (own R&D investment); (ii) the effect is more pronounced for private-owned enterprises (POEs) rather than state-owned enterprises (SOEs), and (iii) especially when they trade with partners in/from advanced markets
P&P protocol: local coordination of mobile sensors for self-deployment
The use of mobile sensors is of great relevance for a number of strategic
applications devoted to monitoring critical areas where sensors can not be
deployed manually. In these networks, each sensor adapts its position on the
basis of a local evaluation of the coverage efficiency, thus permitting an
autonomous deployment.
Several algorithms have been proposed to deploy mobile sensors over the area
of interest. The applicability of these approaches largely depends on a proper
formalization of rigorous rules to coordinate sensor movements, solve local
conflicts and manage possible failures of communications and devices.
In this paper we introduce P&P, a communication protocol that permits a
correct and efficient coordination of sensor movements in agreement with the
PUSH&PULL algorithm. We deeply investigate and solve the problems that may
occur when coordinating asynchronous local decisions in the presence of an
unreliable transmission medium and possibly faulty devices such as in the
typical working scenario of mobile sensor networks.
Simulation results show the performance of our protocol under a range of
operative settings, including conflict situations, irregularly shaped target
areas, and node failures.Comment: Technical repor
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The reshoring of business services: reaction to failure or persistent strategy?
This paper investigates whether reshoring of business services is the result of company response to performance shortcomings of the initiative offshored or instead is motivated by persisting with original offshoring strategy (disintegration advantages, accessing new markets and cost-saving), regardless of offshoring performance. Our empirical analysis, based on data from the Offshoring Research Network, shows that both arguments hold. Moreover, when offshoring had been motivated by accessing to new markets and its performance is unsatisfactory, companies are likely to relocate. However, unsatisfactory performance of activities offshored for efficiency reasons or search of talent, do not necessarily lead companies to relocate elsewhere
In silico clinical trials through AI and statistical model checking
A Virtual Patient (VP) is a computational model accounting for individualised (patho-) physiology and Pharmaco-Kinetics/Dynamics of relevant drugs. Availability of VPs is among the enabling technology for In Silico Clinical Trials. Here we shortly outline the state of the art as for VP generation and summarise our recent work on Artificial Intelligence (AI) and Statistical Model Checking based generation of VPs
Quantum Characterization of a Werner-like Mixture
We introduce a Werner-like mixture [R. F. Werner, Phys. Rev. A {\bf 40}, 4277
(1989)] by considering two correlated but different degrees of freedom, one
with discrete variables and the other with continuous variables. We evaluate
the mixedness of this state, and its degree of entanglement establishing its
usefulness for quantum information processing like quantum teleportation. Then,
we provide its tomographic characterization. Finally, we show how such a
mixture can be generated and measured in a trapped system like one electron in
a Penning trap.Comment: 8 pages ReVTeX, 8 eps figure
Governance choice misfit and firm performance in offshoring innovation: the role of institutional environment
In this paper, we analyse the effect of institutional factors on the relationship between governance choices and business outcomes when offshoring innovation. Grounded in an institutional theory perspective, we use survey data from the ORN database to estimate regression models and identify governance modes related to specific drivers of offshore innovation. We then analyse the effect on firm performance of choosing a governance mode not in line with the one predicted by the model. We find that choosing a fully owned offshoring operation when theory would predict selecting offshore outsourcing has a negative effect on performance, but not vice versa. We also find that institutional factors of rule of law and IPR protection strength in host countries negatively affect firm performance when offshoring innovation activities
Intention to be vaccinated for COVID-19 among italian nurses during the pandemic
Background: While the COVID-19 pandemic has spread globally, health systems are overwhelmed by both direct and indirect mortality from other treatable conditions. COVID-19 vaccination was crucial to preventing and eliminating the disease, so vaccine development for COVID-19 was fast-tracked worldwide. Despite the fact that vaccination is commonly recognized as the most effective approach, according to the World Health Organization (WHO), vaccine hesitancy is a global health issue. Methods: We conducted a cross-sectional online survey of nurses in four different regions in Italy between 20 and 28 December 2020 to obtain data on the acceptance of the upcoming COVID-19 vaccination in order to plan specific interventions to increase the rate of vaccine coverage. Results: A total of 531 out of the 5000 nurses invited completed the online questionnaire. Most of the nurses enrolled in the study (73.4%) were female. Among the nurses, 91.5% intended to accept vaccination, whereas 2.3% were opposed and 6.2% were undecided. Female sex and confidence in vaccine efficacy represent the main predictors of vaccine intention among the study population using a logistic regression model, while other factors including vaccine safety concerns (side effects) were non-significant. Conclusions: Despite the availability of a safe and effective vaccine, intention to be vaccinated was suboptimal among nurses in our sample. We also found a significant number of people undecided as to whether to accept the vaccine. Contrary to expectations, concerns about the safety of the vaccine were not found to affect the acceptance rate; nursesâ perception of vaccine efficacy and female sex were the main influencing factors on attitudes toward vaccination in our sample. Since the success of the COVID-19 immunization plan depends on the uptake rate, these findings are of great interest for public health policies. Interventions aimed at increasing employee awareness of vaccination efficacy should be promoted among nurses in order to increase the number of vaccinated people
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