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The Organization of Global Supply Networks
No full textIn this contribution, we introduce a network approach for the organization of global
production across national borders, beyond the sequential industry-level metrics proposed
in the previous literature. First, we show and argue that several characteristics of
global production processes would be lost in the analysis when assuming that they could
be proxied as linear sequences. Hence, we propose an index that assesses the relevance
of any input for the target output, including its role as an input of inputs. Thereafter,
we exploit an own-built firm-level dataset of about 20,489 U.S. parent companies integrating
more than 154,000 affiliates worldwide. Results show that the technological
relevance of an input in a directed supply network is also a good predictor for: i) the
probability that an input industry is actually integrated within a firm boundary; ii) the
number of affiliates that are controlled by the parent company and active in that input
industry
Social coordination with locally observable types
No full textIn this paper we study the typical dilemma of social coordination between a risk-dominant convention and a payoff-dominant convention. In particular, we consider a model where a population of agents play a coordination game over time, choosing both the action and the network of agents with whom to interact. The main modeling novelties with respect to the existing literature are: (1) Agents come in two distinct types, (2) the interaction with a different type is costly, and (3) an agent’s type is unobservable prior to interaction. We show that when the cost of interacting with a different type is small with respect to the payoff of coordination, the payoff-dominant convention is the only stochastically stable convention; instead, when the cost of interacting with a different type is large, the only stochastically stable conventions are those where all agents of one type play the payoff-dominant action and all agents of the other type play the risk-dominant action
"Learning by experience"? La riforma del ministero dei Beni e delle Attività culturali e del Turismo
No full textThe article examines the reform of the Italian Ministry for Culture and Tourism started in 2014 and its main developments. The first part deals with the history, design and objectives of such administrative reform. The second part explains what kind of leverages made possible to start and to implement the reform process. The third and final part focuses on how the reform could represent a case study from a dual perspective: on the one hand, it displays all the traditional features - and political and bureaucratic behaviours - which one can find in every administrative reform; on the other hand, the reform has produced significant innovation in cultural property law, and in administrative law more generally, under several aspects: regulation, finance, personnel, public and private relationships. Due to its complexity and variety, therefore, cultural property law may become an "atelier" for whoever decides to study administrative law
Trasformazioni dello Stato e riforme nel settore dei beni culturali
No full textThe article moves from Paolo Leon's works in order to illustrate the features and objectives of the 2014 reform of the Italian Ministry of Cultural Heritage and Tourism. It is focused on three issues: the establishment of state museums, the reform of Ministry's field offices (soprintendenze), and the investment in human resources. These reformative actions give evidence of the high significance and modernity of Paolo Leon's scientific and cultural legacy
Programming the Interactions of Collective Adaptive Systems by Relying on Attribute-based Communication
Full text linkCollective adaptive systems are new emerging computational systems consisting of a large number of interacting components and featuring complex behaviour. These systems are usually distributed, heterogeneous, decentralised and interdependent, and are operating in dynamic and possibly unpredictable environments. Finding ways to understand and design these systems and, most of all, to model the interactions of their components, is a difficult but important endeavour. In this article we propose a language-based approach for programming the interactions of collective-adaptive systems by relying on attribute-based communication; a paradigm that permits a group of partners to communicate by considering their run-time properties and capabilities. We introduce AbC, a foundational calculus for attribute-based communication and show how its linguistic primitives can be used to program a complex and sophisticated variant of the well-known problem of Stable Allocation in Content Delivery Networks. Also other interesting case studies, from the realm of collective-adaptive systems, are considered. We also illustrate the expressive power of attribute-based communication by showing the natural encoding of other existing communication paradigms into AbC
AErlang: Empowering Erlang with Attribute-Based Communication
No full textAttribute-based communication provides a novel mechanism to dynamically select groups of communicating entities by relying on predicates over their exposed attributes. In this paper, we embed the basic primitives for attribute-based communication into the functional concurrent language Erlang to obtain what we call AErlang, for attribute Erlang. To evaluate our prototype in terms of performance overhead and scalability we consider solutions of the Stable Marriage Problem based on predicates over attributes and on the classical preference lists, and use them to compare the runtime performance of AErlang with those of Erlang and X10. The outcome of the comparison shows that the overhead introduced by the new communication primitives is acceptable, and our prototype can compete performance-wise with an ad-hoc parallel solution in X10
The census of Enterprise Archives as an Opportunity for the Business. How to teach businessmen to boost their business through their archives, their own energy.
No full textReversibility in session-based concurrency: A fresh look
No full textMuch research has studied foundations for correct and reliable communication-centric software systems. A salient approach to correctness uses verification based on session types to enforce structured communications; a recent approach to reliability uses reversible actions as a way of reacting to unanticipated events or failures. In this paper, we develop a simple observation: the semantic machinery required to define asynchronous (queue-based), monitored communications can also support reversible protocols. We propose a framework of session communication in which monitors support reversibility of (untyped) processes. Main novelty in our approach are session types with present and past, which allow us to streamline the semantics of reversible actions. We prove that reversibility in our framework is causally consistent, and define ways of using monitors to control reversible actions.
Keyword
Modality-independent encoding of individual concepts in the left parietal cortex
No full textAbstract The organization of semantic information in the brain has been mainly explored through category-based models, on the assumption that categories broadly reflect the organization of conceptual knowledge. However, the analysis of concepts as individual entities, rather than as items belonging to distinct superordinate categories, may represent a significant advancement in the comprehension of how conceptual knowledge is encoded in the human brain. Here, we studied the individual representation of thirty concrete nouns from six different categories, across different sensory modalities (i.e., auditory and visual) and groups (i.e., sighted and congenitally blind individuals) in a core hub of the semantic network, the left angular gyrus, and in its neighboring regions within the lateral parietal cortex. Four models based on either perceptual or semantic features at different levels of complexity (i.e., low- or high-level) were used to predict fMRI brain activity using representational similarity encoding analysis. When controlling for the superordinate component, high-level models based on semantic and shape information led to significant encoding accuracies in the intraparietal sulcus only. This region is involved in feature binding and combination of concepts across multiple sensory modalities, suggesting its role in high-level representation of conceptual knowledge. Moreover, when the information regarding superordinate categories is retained, a large extent of parietal cortex is engaged. This result indicates the need to control for the coarse-level categorial organization when performing studies on higher-level processes related to the retrieval of semantic information
Organizing the Global Value Chain: A firm-level test
No full textIn this paper, we study the organization of Global Value Chains on a sample of about 4,000 manufacturing parent companies integrating more than 90,000 affiliates in 150 countries. Assuming a technological sequence of production stages, a recent property rights framework (Antràs and Chor, 2013; Alfaro et al., 2015) predicts that vertical integration decisions are crucially based on both the position of a supplier along the chain and on the relative size of demand elasticities faced by the final-good producer and the supplier. In line with this, we find that if final demand is sufficiently elastic (inelastic), downstream parents, i.e. final-good producers, integrate production stages that are more proximate to (far from) final demand. However, this result is not valid in the case of midstream parents, i.e. producers of intermediate inputs that can integrate either backward or forward along the chain. We document that these companies are at least as common as are downstream parents, but the existing theory neglects them. In these cases, we find that demand elasticities do not play a significant role in integration choices. Interestingly, both midstream and downstream parents tend to integrate affiliates that are more proximate in segments of a supply chain, probably due to technological complementarities in adjacent industries