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We describe a process to compose and decompose choice behavior, called resolution. In the forward direction, resolutions amalgamate simple choices to create a complex one. In the backward direction, resolutions detect when and how a primitive choice can be deconstructed into smaller choices. A choice is resolvable if it is the resolution of smaller choices. Rationalizability, rationalizability by a preorder, and path independence are all preserved (backward and forward) by resolutions, whereas rationalizability by a weak order (equivalently, ) is not. We characterize resolvable choices, and show that resolvability generalizes .

We describe a model that explains possibly indecisive choice behavior, that is, quasi-choices (choice correspondences that may be empty on some menus). The justification is here provided by a proportion of ballots, which are quasi-choices rationalizable by an arbitrary binary relation. We call a quasi-choice $s$-majoritarian if all options selected from a menu are endorsed by a share of ballots larger than $s$. We prove that all forms of majoritarianism are equivalent to a well-known behavioral property, namely Chernoff axiom. Then we focus on two paradigms of majoritarianism, whereby either a simple majority of ballots justifies a quasi-choice, or the endorsement by a single ballot suffices - a liberal justification. These benchmark explanations typically require a different minimum number of ballots. We determine the asymptotic minimum size of a liberal justification.

In the era of Extremely Large Telescopes, the current generation of 8-10m facilities are likely to remain competitive at ground-UV wavelengths for the foreseeable future. The Cassegrain U-Band Efficient Spectrograph (CUBES) has been designed to provide high-efficiency (>40%) observations in the near UV (305-400 nm requirement, 300-420 nm goal) at a spectral resolving power of R>20,000 (with a lower-resolution, sky-limited mode of R ~ 7,000). With the design focusing on maximizing the instrument throughput (ensuring a Signal to Noise Ratio (SNR) ~20 per high-resolution element at 313 nm for U ~18.5 mag objects in 1h of observations), it will offer new possibilities in many fields of astrophysics, providing access to key lines of stellar spectra: a tremendous diversity of iron-peak and heavy elements, lighter elements (in particular Beryllium) and light-element molecules (CO, CN, OH), as well as Balmer lines and the Balmer jump (particularly important for young stellar objects). The UV range is also critical in extragalactic studies: the circumgalactic medium of distant galaxies, the contribution of different types of sources to the cosmic UV background, the measurement of H2 and primordial Deuterium in a regime of relatively transparent intergalactic medium, and follow-up of explosive transients. The CUBES project completed a Phase A conceptual design in June 2021 and has now entered the detailed design and construction phase. First science operations are planned for 2028., SPIE proceedings, SPIE Astronomical Telescopes + Instrumentation 2022, Montr\'eal, Canada; 20 pages, 13 figures, 2 tables

We present the baseline conceptual design of the Cassegrain U-Band Efficient Spectrograph (CUBES) for the Very Large Telescope. CUBES will provide unprecedented sensitivity for spectroscopy on a 8 - 10 m class telescope in the ground ultraviolet (UV), spanning a bandwidth of > 100 nm that starts at 300 nm, the shortest wavelength accessible from the ground. The design has been optimized for end-to-end efficiency and provides a spectral resolving power of R > 20000, that will unlock a broad range of new topics across solar system, Galactic and extraglactic astronomy. The design also features a second, lower-resolution (R \sim 7000) mode and has the option of a fiberlink to the UVES instrument for simultaneous observations at longer wavelengths. Here we present the optical, mechanical and software design of the various subsystems of the instrument after the Phase A study of the project. We discuss the expected performances for the layout choices and highlight some of the performance trade-offs considered to best meet the instrument top-level requirements. We also introduce the model-based system engineering approach used to organize and manage the project activities and interfaces, in the context that it is increasingly necessary to integrate such tools in the development of complex astronomical projects., Accepted for publication in Experimental Astronomy

This paper investigates the role of literature and, in particular, Proust in Merleau-Ponty’s late works’ rehabilitation of the ontology of the sensible. First, I trace Proust’s role in Phenomenology of Percpetion, contrasting it with the somewhat more paradigmatic status as a model it plays in the late works. Second, I compare this with the role of the novel as partial myth in Schelling, who also played an essential role in Merleau-Ponty’s refiguration of the sensible. I briefly trace his examination of the historical or “sociological meaning” of literature through works of the fifties, beginning with his Collège de France candidacy proposal and continuing through his examination of the rationality of modern disenchantment (Entzauberung) or dépoétization in the Adventures of the Dialectic. Finally, discussing the late analysis of Proust against this backdrop, I conclude with considerations concerning the relevance of Merleau-Ponty’s overall analysis of Proust both in his thought and contemporary literary criticism and philosophy more generally. Cet article examine le rôle de la littérature et, en particulier, celui de Proust, dans la réhabilitation ontologique du sensible qui se trame dans les derniers écrits de Merleau-Ponty. En premier lieu, je retracerai le rôle de Proust dans la Phénoménologie de la perception, en l’opposant au statut quelque peu plus paradigmatique, comme s’il s’agissait d’un modèle, qu’il joue dans le dernier Merleau-Ponty. Deuxièmement, je comparerai cela avec la fonction du roman conçu comme un mythe incomplet chez Schelling, qui a aussi joué un rôle essentiel dans la reconfiguration du sensible chez Merleau-Ponty. Je décrirai brièvement son analyse de la « signification sociologique » ou historique de la littérature à travers des oeuvres des années ’50, en me penchant, d’abord, sur sa candidature au Collège de France, et, ensuite, sur son étude de la rationalité du désenchantement moderne (Entzauberung) ou dépoétisation dans les Aventures de la dialectique. Finalement, en examinant les dernières analyses de Proust à partir de ces prémisses, je conclurai avec des considérations sur l’intérêt de l’ensemble de l’analyse que Merleau-Ponty fait de Proust à la fois pour sa pensée, pour la critique littéraire contemporaine et, plus généralement, pour la philosophie.Il presente articolo indaga il ruolo della letteratura e, in particolare, di Proust nella riabilitazione ontologica del sensibile negli ultimi scritti di Merleau-Ponty. In primo luogo, si delinea il ruolo di Proust nella Fenomenologia della percezione, contrapponendolo, in qualche modo, allo statuto paradigmatico di modello che l’autore riveste nei lavori dell’ultimo Merleau-Ponty. In secondo luogo, si confronta questo con il ruolo del romanzo come mito parziale in Schelling, che pure ha giocato una parte essenziale nella rifigurazione del sensibile in Merleau-Ponty. Si articolerà brevemente il significato storico o sociologico della letteratura attraverso gli scritti degli anni Cinquanta, a partire dalla proposta di candidatura di Merleau-Ponty al Collège de France e proseguendo mediante il suo esame della razionalità del disincanto moderno (Entzauberung) o depoetizzazione ne Le avventure della dialettica. Infine, esaminando l’ultima lettura di Proust a partire da queste analisi, propongo una considerazione riguardo alla rilevanza complessiva dell’autore della Recherche nella riflessione di Merleau-Ponty e, più in generale, nella critica letteraria e nella filosofia contemporanee.

This paper compares two different approaches to pursue multiple premiums: a combination approach (market portfolio plus factor portfolios) and a fully integrated approach. We evaluate the two approaches via multiple lenses: pursuit of higher expected returns, distribution of over- and underweights, turnover, and costs. Our analysis shows the integrated approach can lead to greater reliability of outperformance, better risk control, and lower costs. These benefits are critical to an efficient pursuit of multiple premiums and cannot be replicated through combination approaches.

MOONS (Multi-Object Optical and near-Infrared Spectrograph) will be a fibre-fed, optical to near-infrared multi-objet spectrograph designed to utilise the full 25 arcminute diameter field-of-view of the Very Large Telescope and with a multiplex capability of over 1000 fibres. The baseline design includes a single focal plate and fibre positioning subsystem, consisting of up 1024 small dual radial arm modules, which are used to place each fibre, in the exact x, y and z position in the telescope focal plane. Each fibre has a microlens to focus the beam into the fibre at a relatively fast focal ratio of F/3.65 to reduce the Focal Ratio Degradation (FRD). The light is then fed through the fibres to two identical, cryogenic triple arm spectrographs, mounted on the instrument platform. In each spectrograph, the light from 512 fibres, arranged in a pseudo-slit, is split by dichroic filters into three channels (RI, YJ and H) and dispersed on to 4k x 4k detectors in each channel.

The Multi Object Optical and Near-infrared Spectrograph (MOONS) instrument is the next generation multi-object spectrograph for the VLT. This powerful instrument will combine for the first time: the large collecting power of the VLT with a high multipexing capability offered by 1000 optical fibres moved with individual robotic positioners and a novel, very fast spectrograph able to provide both low- and high-resolution spectroscopy simultaneously across the wavelength range 0.64μm - 1.8μm. Such a facility will provide the astronomical community with a powerful, world-leading instrument able to serve a wide range of Galactic, Extragalactic and Cosmological studies. Th final assembly, integration and verification phase of the instrument is now about to start performance testing.

MOONS will be the next Multi-Object Optical and Near-infrared Spectrograph for the Very Large Telescope, able to simultaneously observe 1000 targets, feeding a set of optical fibres which can be placed at user-specified locations on the Nasmyth focal plane using individual robotic positioners. The sub-fields thus selected are then driven by the fibres into two identical cryogenic spectrographs mounted on the Nasmyth platform of one of the ESO VLT 8 m telescopes. The instrument will provide both medium and high-resolution spectral coverage across the wavelength range of 0.65 μm to 1.8 μm. In this paper we will describe the two components that interface with the telescope: the MOONS Field Corrector (FC) and the Rotating Front End (RFE) Assemblies. The FC optics will correct the off-axis aberrations of the telescope, as well as determining the shape of the focal surface and the pupil location. The RFE assembly consists of a rotating part, which will be mounted on the VLT Nasmyth Rotator, and be connected to the two static Spectrographs via fibre assemblies, and all the sub-systems that give support to the fibre positioning, metrology and calibration units.

The Multi-Object Optical and near-Infrared Spectrograph (MOONS) will exploit the full 500 square arcmin field of view offered by the Nasmyth focus of the Very Large Telescope and will be equipped with two identical triple arm cryogenic spectrographs covering the wavelength range 0.64μm-1.8μm, with a multiplex capability of over 1000 fibres. Each spectrograph will produce spectra for 500 targets simultaneously, each with its own dedicated sky fibre for optimal sky subtraction. The system will have both a medium resolution (R~4000-6000) mode and a high resolution (R~20000) mode. The fibres are used to pick off each sub field of 1” and are used to transport the light from the instrument focal plane to the two spectrographs. Each fibre has a microlens to focus the beam into the fibre at a relative fast focal ratio of F/3.65 to reduce the Focal Ratio Degradation (FRD). This paper describes the final characteristics and performances of the MOONS fibre link, and their installation status into the slit of the spectrograph during the integration phase in Europe.

Domestic zonal heating controls enable hydronic systems to heat rooms to different temperatures at different times. The first credible evidence known to the authors, of the in-use energy savings of such controls, is reported. The results and research methods are globally relevant. The energy demands and room temperatures in 68, gas-heated, owner-occupied, semi-detached homes, in the English Midlands were monitored for a year before zonal controls were fitted in 37 of the homes prior to the second year of monitoring. The other homes retained the existing heating controls and so provided a matched (control) group. Surveys and questionnaires characterised the dwellings, heating systems and households. In two thirds of the homes with zonal controls the annual gas demand decreased, in one third it increased. Overall, the mean gas demand decreased by 3.5% relative to the homes that retained their existing controls. Savings were achieved primarily by reducing bedroom temperatures, especially in the evenings. Wireless, digital zonal controls are unlikely to provide an acceptable payback through reductions in energy bills at today’s prices, but they offer households the flexibility to react to time-of-use energy pricing. A matched (control) group is essential for the reliable calculation of energy demand changes arising from interventions in occupied homes.

A choice space is a finite set of alternatives endowed with a map associating to each menu a nonempty subset of selected items. A congruence on a choice space is an equivalence relation that preserves its structure. Intuitively, two alternatives are congruent if the agent is indifferent between them, and, in addition, her choice is influenced by them in exactly the same way. We give an axiomatic characterization of the notion of congruence in terms of three natural conditions: binary fungibility, common destiny, and repetition irrelevance. Further, we show that any congruence satisfies the following desirable properties: (hereditariness) it induces a well-defined choice on the quotient set of equivalence classes; (reflectivity) the primitive behavior can be always retrieved from the quotient choice, regardless of any feature of rationality; (consistency) all basic axioms of choice consistency are preserved back and forth by passing to the quotient. We also prove that the family of all congruences on a choice space forms a lattice under set-inclusion, having equality as a minimum, and a unique maximum, called revealed indiscernibility. The latter relation can be seen as a limit form of revealed similarity as the agent’s rationality increases.

The transitivity of a preference relation is a traditional tenet of rationality in economic theory. However, several weakenings of transitivity have proven to be extremely useful in applications, giving rise to the notions of interval orders and semiorders among others. Strict ( m , 1 ) -Ferrers properties go in this direction, classifying asymmetric preferences on the basis of their degree of transitivity, which becomes generally weaker as m gets larger. We show that strict ( m , 1 ) -Ferrers properties can be arranged into a poset contained in the reverse ordering of the natural numbers. Our main result completely describes this poset. Although this paper has a combinatorial flavor, the topic of Ferrers properties is suited to applications in economics and psychology, for instance in relation to money-pump phenomena.

The summer 2018 saw temperatures far above the long-term average in the Northern Hemisphere. It was England's hottest ever summer, with temperatures typical of those expected of the 2050s. In the largest and most comprehensive study to date, summertime overheating in 750 English homes was assessed through both monitoring and questionnaires. Overheating determined using adaptive thermal comfort criteria invariably produced patterns of overheating with dwelling and household characteristics comparable with self-reported results for both living rooms and bedrooms. However, households with members aged over 75 significantly under-reported the prevalence of overheating compared with monitored results. The standard UK static overheating criterion produced implausible estimates for the prevalence of overheating in bedrooms. Weighting the results to the national stock revealed that 4.6million English bedrooms (19% of the stock) and 3.6million living rooms (15%) overheated. Overheating was more prevalent in bedrooms at night than in living rooms during the day. The prevalence of living room overheating was significantly greater in flats (30%) than other dwelling types. Improved fabric energy efficiency did not significantly increase the risk of overheating. The prevalence of monitored overheating was greater in households living in social housing, with low incomes or with members aged over state pension age. Recommendations are made about the measurement of overheating and the formulation of policies aimed at mitigating the risk of overheating in existing homes.

A NaP-preference (necessary and possible preference) is a pair of nested reflexive relations on a set such that the smaller is transitive, the larger is complete, and the two relations jointly satisfy properties of transitive coherence and mixed completeness. It is known that a NaP-preference is characterized by the existence of a set of total preorders whose intersection and union give its two components. We introduce the symmetric counterpart of a NaP-preference, called a NaP-indifference: this is a pair of nested symmetric relations on a set such the smaller is an equivalence relation, and the larger is a transitively coherent extension of the first. A NaP-indifference can be characterized by the existence of a set of equivalence relations whose intersection and union give its two components. NaP-indifferences naturally arise in applications: for instance, in the field of individual choice theory, suitable pairs of similarity relations revealed by a choice correspondence yield a NaP-indifference. We classify NaP-indifferences in two categories, according to their genesis: (i) derived, which are canonically obtained by taking the symmetric part of a NaP-preference; (ii) primitive, which arise independently of the existence of an underlying NaP-preference. This partition into two classes turns out to be related to the notion of incomparability graph.

A NaP-preference (necessary and possible preference) is a pair of nested reflexive relations on a set such that the smaller is transitive, the larger is complete, and the two components jointly satisfy natural forms of mixed completeness and transitive coherence. A NaP-preference is normalized if its smaller component is a partial order. We show that normalized NaP-preferences on a finite set are well-graded in the sense of Doignon and Falmagne (1997).

Heating homes using gas boilers is incompatible with the UK’s target of net-zero greenhouse gas emissions by 2050. One solution is to shift to heat pumps (HPs) supplied from decarbonised power plant, but this could place an unmanageable burden on the electricity supply network. National heat demand profiles depend on the heating patterns adopted by households which, in turn, depend on the type of heating system and its control. The largest data sets available, from around 6600 gas-heated homes and 600 homes with HPs, are used to create an empirical model of Great Britain’s (GB) half-hourly domestic heat demand. The model is used to estimate the annual half-hourly heat demand of the GB housing stock for both current and future weather conditions. The demand profile when using HPs is compared to the current profile for gas heating. In a cold year, the calculated total annual heat demand of a typical mix of ground source and air-source HPs was 422TWh, 8% greater for than for gas-heated homes. However, the peak heat demand of 157GW was 8% lower than for gas heating, and the maximum heat ramp rate of 21GW/h, 67% lower. These results are due to the different ways that households use gas boilers and HPs. The accurate modelling of heating patterns is necessary to achieve reliable predictions of national heat demand. Policy initiatives, financial incentives or other interventions that influence the daily pattern of HP usage could also have a marked and positive influence on the GB heat demand profile.

Rationalizability has been a main topic in individual choice theory since the seminal paper of Samuelson (1938). The rationalization of a multi-valued choice is classically obtained by maximizing the binary relation of revealed preference, which is fully informative of the primitive choice as long as suitable axioms of choice consistency hold. In line with this tradition, we give a purely axiomatic treatment of the topic of choice rationalization. In fact, we introduce a new class of properties of choice coherence, called axioms of replacement consistency, which examine how the addition of an item to a menu may cause a substitution in the selected set. These axioms are used to uniformly characterize rationalizable choices such that their revealed preferences are quasi-transitive, Ferrers, semitransitive, and transitive. Further, regardless of rationalizability, we study the relationship of these new axioms with some classical properties of choice consistency, such as standard contraction, standard expansion, and WARP . To complete our analysis of the transitive structure of rationalizable choices, we examine the case of revealed preferences satisfying weak ( m , n ) -Ferrers properties in the sense of Giarlotta and Watson (2014). Originally introduced with the purpose of extending the notions of interval orders and semiorders, these Ferrers properties give a descriptive taxonomy of binary relations displaying a transitive strict preference but an intransitive indifference. Here we suggest a possible economic interpretation of weak ( m , n ) -Ferrers properties, showing that, in a suitable model of transactions, they provide a way of controlling phenomena of money-pump due to the presence of mixed cycles of preference/indifference. Finally, we define ( m , n ) -rationalizable choices as those having a weakly ( m , n ) -Ferrers revealed preference, and characterize these choices by means of additional axioms of replacement consistency.