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We review several applications of the implicit parametrization theorem in optimization. In nonlinear programming, we discuss both new forms, with less multipliers, of the known optimality conditions, and new algorithms of global type. For optimal control problems, we analyze the case of mixed equality constraints and indicate an algorithm, while in shape optimization problems the emphasis is on the new penalization approach.

This work mainly aims to propose a new design procedure combining the benefits of the Performance-Based Plastic Design approach (PBPD) with a rigorous accounting of second-order effects. In fact, by exploiting the kinematic theorem of plastic collapse, second-order effects can be accounted for employing the concept of collapse mechanism equilibrium curve. The same tool constitutes the base of the Theory of Plastic Mechanism Control (TPMC) design approach. Besides, the paper reports a critical comparison between TPMC and PBPD, both having the scope to design structures exhibiting a collapse mechanism of global type. These two approaches are also compared with the refined PBPD where second-order effects are accounted for by the kinematic approach. Many steel moment resisting frames are designed according to PBPD, TPMC and refined PBPD and their performances have been compared on the bases of push-over analyses.

This study utilized a long-term (2001-2018) aerosol optical component dataset retrieved from the Multiangle Imaging Spectroradiometer (MISR), Version 23, to perform comprehensive analyses of the global climatology of seasonal AODs, partitioned by aerosol types (including small-size, medium-size, large-size, spherical, and non-spherical). By dividing eight different AOD bins and performing trend analysis, the seasonal variability and trends in these type-segregated AODs, as well as in the frequency occurrences (FOs) for different AOD bins, globally and over 12 regions of interest, were also investigated. In terms of particle size, small-size aerosol particles (diameter0.7 μm) contribute the largest to global extinction in all three seasons except winter. A similar globally dominant role is exhibited by spherical aerosols, which contribute 68.5%, 73.3%, 71.6% and 70.2% to the global total AOD (TAOD) in spring, summer, autumn and winter, respectively, on a global average scale. FOs with different aerosol loading levels suggested that the seasonal FOs tend to decrease progressively with increasing aerosol loading, except for Level 1 (TAOD0.05). Examination of the seasonal distribution of FOs revealed that the FO at Level 1 (Level 2, 0.05TAOD0.15) is much larger in summer/winter (winter/autumn) than in spring/autumn (spring/summer) over most areas of the world. However, the FOs for Level 3 (0.15TAOD0.25) to Level 8 (TAOD1.0) generally exhibit greater intensity in spring/summer than in autumn/winter. Temporal trend analyses showed that the seasonal TAOD experiences a significant decline during 2001-2018 in most regions globally, except in South Asia, the Middle East, and North Africa. Opposite seasonal trends in the above regions are closely related to the increase in FOs in the range of 0.4TAOD1.0. The global average TAOD shows the most pronounced decline in spring, falling by -10.4% (P0.05). Examination of the trends in type-segregated AODs further revealed that the decreases in size-segregated (shape-segregated) AODs all contribute to the decrease in seasonal TAOD, with small-size AOD (spherical AOD) contributing most significantly.

International audience; Multiparty sessions are systems of concurrent processes, which allow several participants to communicate by sending and receiving messages. Their overall behaviour can be described by means of global types. Typable multiparty sessions enjoy lock-freedom. We look at multiparty sessions as open systems by allowing one to compose multiparty sessions by transforming two of their participants into a pair of coupled gateways, forwarding messages between the two sessions. Gateways need to be compatible. We show that the session resulting from the composition can be typed, and its type can be computed from the global types of the starting sessions. As a consequence, lock-freedom is preserved by composition. Compatibility between global types is necessary, since systems obtained by composing sessions with incompatible global types have locks (or they are not sessions). We also define direct composition, which allows one to connect two global types without using gateways. Finally, we propose a decomposition operator, to split a global type into two, which is the left inverse of direct composition. Direct composition and decomposition on global types prepare the ground for a novel framework allowing for the modular design and implementation of distributed systems.

We introduce partial sessions and partial (multiparty) session types, in order to deal with open systems, i.e., systems with missing components. Partial sessions can be composed, and the type of the resulting system is derived from those of its components without knowing any suitable global type nor the types of missing parts. Incompatible types, due to e.g. miscommunications or deadlocks, are detected at the merging phase. We apply these types to a process calculus, for which we prove subject reduction and progress, so that well-typed systems never violate the prescribed constraints. Therefore, partial session types support the development of systems by incremental assembling of components.

In this paper we study regularity of partial differential equations with polynomial coefficients in non isotropic Beurling spaces of ultradifferentiable functions of global type. We study the action of transformations of Gabor and Wigner type in such spaces and we prove that a suitable representation of Wigner type allows to prove regularity for classes of operators that do not have classical hypoellipticity properties.

Takotsubo syndrome (TTS), characterised by transient left ventricular systolic dysfunction, is divided into five types: (1) apical ballooning, (2) mid-ventricular, (3) basal or inverted, (4) and focal wall-motion patterns, and (5) other types, including biventricular type, isolated right ventricular and global type. The common clinical features of TTS are similar to acute coronary syndrome, which makes them indistinguishable in the early stages. TTS has a wide spectrum of emotional or physical triggers. Pheochromocytoma has been widely recognised as a distinct physical trigger of TTS. Although reports of pheochromocytoma causing TTS are not uncommon, spontaneous rupture of pheochromocytoma causing TTS is extremely rare because of the low incidence of tumour rupture. Here we report on a case of a 31-year-old man with adrenal pheochromocytoma rupture developing basal TTS.

Detecting abrupt changes in streaming graph signals is relevant in a variety of applications ranging from energy and water supplies, to environmental monitoring. In this paper, we address this problem when anomalies activate localized groups of nodes in a network. We introduce an online change-point detection algorithm, which is fully distributed across nodes to monitor large-scale dynamic networks. We analyze the detection statistics for controlling the probability of a global type 1 error. Finally we illustrate the detection and localization performance with simulated data.

In the derived category of modules over a commutative noetherian ring a complex $G$ is said to generate a complex $X$ if the latter can be obtained from the former by taking summands and finitely many cones. The number of cones required in this process is the generation time of $X$. In this paper we present some local to global type results for computing this invariant, and discuss applications., Revision. Incorporate Section 3 into Section 2. To appear in Homology, Homotopy and Applications

Communicating Finite State Machines (CFSMs) are an established model for describing and analysing distributed systems whose concurrently running components communicate via FIFO-channels. Systems of CFSMs are usually considered as closed systems which do not provide access points for communication with the environment. In our study we relax this view such that certain components of a CFSM system can be looked at as describing the behaviour of the environment interacting with the system. They are considered as interfaces and if two systems posses compatible interfaces (according to a natural notion of compatibility) they can be connected. We propose a novel connection mechanism such that interface CFSMs are replaced by automatically generated “gateway” CFSMs, enabling messages to be exchanged between the systems. As a crucial outcome of our approach we prove that, under mild assumptions, if CFSM systems are connected in such a way a number of important communicating properties is preserved: deadlock-freeness, strong deadlock-freeness, orphan-message freeness, freeness of unspecified receptions, and progress. The communication properties we consider are those enjoyed by CFSM systems obtained by end-point projections of certain global type formalisms used in the field of asynchronous multiparty session types. To this end we introduce a parametric syntax to compose global types via interface roles. As a consequence of our preservation results we get for free that composed projected systems enjoy the communication properties.

The additional complexity caused by concurrently communicating processes in distributed systems render the verification of such systems into a very hard problem. Multiparty session types were developed to govern communication and concurrency in distributed systems. As such, they provide an efficient verification method w. r. t. properties about communication and concurrency, like communication safety or progress. However, they do not support the analysis of properties that require the consideration of concrete runs or concrete values of variables. We sequentialise well-typed systems of processes guided by the structure of their global type to obtain interaction-free abstractions thereof. Without interaction, concurrency in the system is reduced to sequential and completely independent parallel compositions. In such abstractions, the verification of properties such as e. g. data-based termination that are not covered by multiparty session types, but rely on concrete runs or values of variables, becomes significantly more efficient.

The paper presents a data-driven model of self-adaptivity for multiparty sessions. System choreography is prescribed by a global type. Participants are incarnated by processes associated with monitors, which control their behaviour. Each participant can access and modify a set of global data, which are able to trigger adaptations in the presence of critical changes of values. The use of the parallel composition for building global types, monitors and processes enables a significant degree of flexibility: an adaptation step can dynamically reconfigure a set of participants only, without altering the remaining participants, even if the two groups communicate., In Proceedings PLACES 2016, arXiv:1606.05403

Intraoperative neuromonitoring identifies recurrent laryngeal nerve (RLN) injury and gives prognostic information regarding postoperative glottic function. Loss of the neuromonitoring signal (LOS) signifies segmental type 1 or global type 2 RLN injury. This study aimed at identifying risk factors for RLN injury and determining vocal fold (VF) function initially and 6 months after definitive LOS.

This work is supported by NOVA LINCS (UID/CEC/04516/2013), EPSRC EP/K034413/1, EP/K011715/1, EP/L00058X/1, EP/N027833/1 and EP/N028201/1. In multiparty session types, interconnection networks identify which roles in a session engage in communication (i.e., two roles are connected if they exchange a message). In session-based interpretations of linear logic the analogue notion corresponds to determining which processes are composed, or cut, using compatible channels typed by linear propositions. In this work, we show that well-formed interactions represented in a session-based interpretation of classical linear logic (CLL) form strictly less-expressive interconnection networks than those of a multiparty session calculus. To achieve this result, we introduce a new compositional synthesis property dubbed partial multiparty compatibility (PMC), enabling us to build a global type denoting the interactions obtained by iterated composition of well-typed CLL threads. We then show that CLL composition induces PMC global types without circular interconnections between three (or more) participants. PMC is then used to define a new CLL composition rule that can form circular interconnections but preserves the deadlock-freedom of CLL. authorsversion published

Background The characteristics of segmental type 1 and global type 2 injuries to the recurrent laryngeal nerve (RLN) and the extent and dynamics of nerve recovery are poorly understood. Methods This investigation of 785 patients who underwent thyroidectomy under continuous intraoperative nerve monitoring aimed at exploring the dynamics of loss and recovery of the nerve monitoring signal and its relationship to early postoperative vocal fold palsy. Results Persistent complete loss of signal and signal recovery

The Theory of Plastic Mechanism Control (TPMC) has been recently extended to the case of Eccentrically Braced Frames (EBFs) with inverted Y-scheme, i.e., EBFs with vertical links. In this paper a further validation of the design procedure, based on TPMC, is provided by means of Incremental Dynamic Analyses (IDA) pointing out the fulfilment of the design goal, i.e., the development of a pattern of yielding consistent with the collapse mechanism of global type where all the links are yielded and all the beams are yielded at their ends while all the columns and the diagonal braces remain in elastic range with the only exception of the base sections of first storey columns. In particular, a study case is designed according to both TPMC and Eurocode 8 provisions and the corresponding seismic performances are investigated by both push-over and IDA analyses. The results show the different performances obtained in terms of pattern of yielding, maximum interstorey drift, link plastic rotation demand and sharing of the seismic base shear between the moment-resisting part and the bracing part of the structural system. The seismic performance improvement obtained by means of TPMC, compared to Eurocode 8 provisions, is pointed out.

In the present work a design approach aiming to the use of high strength steel (HSS) in seismic resistant structures is presented. In particular, in order to exploit all the possible benefits deriving from the use of high strength steel, without adversely affecting local and global ductility supply, the use of MR-Frames with normal steel beams and properly designed HSS columns is proposed. Column sections are dimensioned by means of the Theory of Plastic Mechanism Control (TPMC) to guarantee structures failing according to a global type mechanism aiming to assure that HSS columns remain in elastic range. In addition, aiming to prevent column yielding also at the base of first storey, column-base connections are designed to transmit axial and shear forces only, thus completely preventing column hinging, but reducing the structural lateral stiffness. Therefore, serviceability requirements are assured by means of brace members, so that the structure behaves like a MRF-CBF dual system. The fulfilment of the design goal has been pointed out by means of both push-over and nonlinear dynamic analyses whose results are herein presented and discussed.

This paper considers the realisation of lambda expressions in Java 8 on the basis of a global type inference algorithm, which we have introduced in Java-TX. We demonstrate that the Java 8 approach has indeed some benefits but also a number of drawbacks. In order to eliminate the drawbacks, we take into consideration the approaches in a former experimental Java version (strawman approach) and in Scala. We show that an integration of these approaches eliminates the drawbacks without losing the benefits of the Java 8 approach. Additionally, we adapt our global type inference algorithm to this extended language.

A multiparty session forms a unit of structured communication among many participants which follow communication sequences specified as a global type. When a process is engaged in two or more sessions simultaneously, different sessions can be interleaved and can interfere at runtime. Previous work on multiparty session types has ignored session interleaving, providing a limited progress property ensured only within a single session, by assuming non-interference among different sessions and by forbidding delegation. This paper develops, besides a more traditional, compositionalcommunicationtype system, a novel staticinteractiontype system for global progress in dynamically interleaved and interfered multiparty sessions. The interaction type system infers causalities of channels making sure that processes do not get stuck at intermediate stages of sessions also in presence of delegation.

Global session types prevent participants from waiting for never coming messages. Some interactions take place just for the purpose of informing receivers that some message will never arrive or the session is terminated. By decomposing a big global type into several light global types, one can avoid such kind of redundant interactions. Lightening global types gives us cleaner global types, which keep all necessary communications. This work proposes a framework which allows to easily decompose global types into light global types, preserving the interaction sequences of the original ones but for redundant interactions., In Proceedings PLACES 2014, arXiv:1406.3313

One of the primary purposes in structural design of seismic-resistant structures is the prevention of undesired collapse mechanisms, involving only a few storeys, which are not satisfactory in terms of energy dissipation capacity. The optimization of the seismic structural response can be achieved with a collapse mechanism of global type, because, in this case, all the dissipative zones are involved in the corresponding pattern of yielding, while all the other non-dissipative structural parts remain in elastic range. In order to promote the development of a collapse mechanism of global type, modern seismic codes provide simple design rules based on so-called hierarchy criteria. However, even though these simple criteria are able to ensure that “soft storey” mechanisms are prevented, they are not able to lead to the development of a collapse mechanism of global type. Therefore, more sophisticated design procedures based on rigid-plastic analysis have been proposed to assure such design goal. In this paper, within the framework of the theory of plastic mechanism control, rigid-plastic analysis of EB-Frames with inverted Y-scheme is carried out including moment–shear interaction aiming to the development of simple hierarchy criteria to be applied with reference to the single storeys to prevent undesired collapse mechanisms. Therefore, reference is made to the simple one-storey scheme. Conversely, the whole theory of plastic mechanism control for EB-Frames with inverted Y-scheme will be presented in a forthcoming paper dealing with multi-storey EB-Frames. Finally, the effectiveness of the proposed hierarchy criteria has been verified by several push over analyses.

This work extends asynchronous multiparty session types (MPST) with explicit connection actions to support protocols with op- tional and dynamic participants. The actions by which endpoints are connected and disconnected are a key element of real-world protocols that is not treated in existing MPST works. In addition, the use cases motivating explicit connections often require a more relaxed form of mul- tiparty choice: these extensions do not satisfy the conservative restric- tions used to ensure safety in standard syntactic MPST. Instead, we de- velop a modelling-based approach to validate MPST safety and progress for these enriched protocols. We present a toolchain implementation, for distributed programming based on our extended MPST in Java, and a core formalism, demonstrating the soundness of our approach. We discuss key implementation issues related to the proposed extensions: a practi- cal treatment of choice subtyping for MPST progress, and multiparty correlation of dynamic binary connections.

Let $F$ be a complete discrete valuation field whose residue field $k$ is a global field of positive characteristic $p$. Let $D$ be a central division $F$-algebra of $p$-power degree. We prove that the subgroup of $F^*$ consisting of reduced norms of $D$ is exactly the kernel of the cup product map $\lambda\in F^*\mapsto (D)\cup(\lambda)\in H^3(F,\,\mathbb{Q}_{p}/\Z_{p}(2))$, if either $D$ is tamely ramified or of period $p$. This gives a $p$-torsion counterpart of a recent theorem of Parimala, Preeti and Surech, where the same result is proved for division algebras of prime-to-$p$ degree., Comment: 16 pages

An extensive experimental campaign has been conducted at EUCENTRE to understand the dynamic behavior of historic stone masonry structures and evaluate the seismic performance of selected strengthening strategies, aimed at improving wall-to-floor connections and in-plane diaphragm stiffness. Shaking table tests were performed of full-scale two-storey buildings in undressed double-leaf stone masonry with timber floor and roof. A first prototype (Building 1), representing a vulnerable building without antiseismic detailing and devices, was tested showing a response characterized by in-plane distortion of the flexible diaphragms and local out-of-plane failure mechanisms. In Building 2 the wall-to-diaphragm connections were improved, providing only a moderate in-plane stiffening of the wooden diaphragms. When subjected to shake-table testing, the strengthened building showed a global type of structural response without the occurrence of out-of-plane mechanisms. In the present paper the strengthening interventi...

The safety of civil engineering structures is one of the most important issues of building industry. That is why the assessment of the damage-involved structural response has recently become of major concern to engineers. Among a number of different approaches to diagnosis of damage, the method of measuring the changes in natural frequencies is considered to be one of the most effective indicators of global damage. From the practical point of view, the method has been successfully applied to relatively small structures, while in-situ tests on large structures, such as bridges, tanks or dams, are very difficult. The aim of the present paper is to show the results of the numerical analysis concerning the diagnosis of damage in a cylindrical steel tank with self-supported roof which is filled with liquid. The tests have been conducted for various stages of damage, introduced in the numerical model by reducing the stiffness of tank-soil system as well as by cutting the connection between the shell and roof of the tank as well as between roof elements. The results of the numerical analysis have shown the characteristic decrease in the natural frequencies for the case of tank-soil system with reduced stiffness, which is the global type of damage. On the other hand, cutting the welds, which can be considered as the local type of damage, has not lead to the differences in the natural frequency values, although differences in local deformations of shell in the vicinity of cuts have been observed in vibration modes.

By classifying behaviors rather than data values, behavioral types abstract structured protocols and enforce disciplined message-passing programs. Many different behavioral type theories have been proposed: they offer a rich landscape of models in which types delineate concurrency and communication. Unfortunately, studies on formal relations between these theories are incipient. This paper argues that clarifying the relative expressiveness of these type systems is a pressing challenge for formal techniques in distributed systems. We overview works that address this issue and discuss promising research avenues.

We prove that every type of finite Cantor-Bendixson rank over a model of a first-order theory without the strict order property is definable and has a unique nonforking extension to a global type. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This study presents an evaluation of Norwegian kyanite quartzites from Gullsteinberget, Knosberget, Kjeks- berget, Sormbrua, Tverradalen, Juovvacorru and Nasafjellet as potential deposits of high-purity quartz (HPQ) for use as raw material for special applications in high-technology industries. Fine-grained quartz, which forms 70 to 85 vol.% of these rocks, generally contains less than 50 μ gg −1 (total sum) of the structurally incorporated trace elements B, Li, Al, Ge, Ti, Fe, Mn, K and P. The concentrations are in the same range as those found in HPQ products, which are being mined and produced in Norway and elsewhere. Quartz analyses were performed using laser ablation- inductively coupled plasma mass spectrometry. Compli- mentary whole-rock analyses and cathodoluminescence studies of quartz were carried out to reveal processes, which have led to the low trace-element concentrations in quartz. This discovery, together with a better knowledge of the processes leading to the formation of HPQ in kyanite quartzites, could lead to the recognition of a new global type of HPQ resource applicable for industrial use. However, the processing technology necessary to separate HPQ from kyanite quartzite economically has not been developed so far.