Data and performance of an active-set truncated Newton method with non-monotone line search for bound-constrained optimization

In this data article, we report data and experiments related to the research article entitled “A Two-Stage Active-Set Algorithm for Bound-Constrained Optimization”, by Cristofari et al. (2017). The method proposed in Cristofari et al. (2017), tackles optimization problems with bound constraints by properly combining an active-set estimate with a truncated Newton strategy. Here, we report the detailed numerical experience performed over a commonly used test set, namely CUTEst (Gould et al., 2015). First, the algorithm ASA-BCP proposed in Cristofari et al. (2017) is compared with the related method NMBC (De Santis et al., 2012). Then, a comparison with the renowned methods ALGENCAN (Birgin and Martínez et al., 2002) and LANCELOT B (Gould et al., 2003) is reported

Immune cells and preterm labour:do invariant NKT cells hold the key?

We have developed our original made-to-measure (M2M) algorithm, PRIMAL, with the aim of modelling the Galactic disc from upcoming Gaia data. From a Milky Way like N-body disc galaxy simulation, we have created mock Gaia data using M0III stars as tracers, taking into account extinction and the expected Gaia errors. In PRIMAL, observables calculated from the N-body model are compared with the target stars, at the position of the target stars. Using PRIMAL, the masses of the N-body model particles are changed to reproduce the target mock data, and the gravitational potential is automatically adjusted by the changing mass of the model particles. We have also adopted a new resampling scheme for the model particles to keep the mass resolution of the N-body model relatively constant. We have applied PRIMAL to this mock Gaia data and we show that PRIMAL can recover the structure and kinematics of a Milky Way like barred spiral disc, along with the apparent bar structure and pattern speed of the bar despite the galactic extinction and the observational errors

Hybridization of multi-objective deterministic particle swarm with derivative-free local searches

The paper presents a multi-objective derivative-free and deterministic global/local hybrid algorithm for the efficient and effective solution of simulation-based design optimization (SBDO) problems. The objective is to show how the hybridization of two multi-objective derivative-free global and local algorithms achieves better performance than the separate use of the two algorithms in solving specific SBDO problems for hull-form design. The proposed method belongs to the class of memetic algorithms, where the global exploration capability of multi-objective deterministic particle swarm optimization is enriched by exploiting the local search accuracy of a derivative-free multi-objective line-search method. To the authors best knowledge, studies are still limited on memetic, multi-objective, deterministic, derivative-free, and evolutionary algorithms for an effective and efficient solution of SBDO for hull-form design. The proposed formulation manages global and local searches based on the hypervolume metric. The hybridization scheme uses two parameters to control the local search activation and the number of function calls used by the local algorithm. The most promising values of these parameters were identified using forty analytical tests representative of the SBDO problem of interest. The resulting hybrid algorithm was finally applied to two SBDO problems for hull-form design. For both analytical tests and SBDO problems, the hybrid method achieves better performance than its global and local counterparts

Modelli Matematici di Storie D'Amore

In questo articolo sono descritti i principali risultati finora ottenuti nel contesto della modellistica delle relazioni d’amore. I modelli sono di tipo descrittivo e stu- diano l’evoluzione dei sentimenti di due individui a partire da uno stato iniziale di indifferenza fino al raggiungimento di un regime sentimentale stazionario, periodi- co, o addirittura aperiodico. I modelli pi`u semplici sono costituiti da due equazioni differenziali (una per lei e una per lui) contenenti le informazioni essenziali sul mo- do con cui ogni individuo reagisce all’amore e al fascino dell’altro. Analizzando i modelli si possono ricavare, senza bisogno di alcun dato, le propriet`a fondamentali delle storie d’amore tra individui di varie categorie: sicuri o insicuri, non polarizzati o polarizzati (tra cui, platonici o sinergici), ... Cos`ı facendo si capisce, ad esempio, perch´e in coppie di individui sicuri ci sia una marcata tendenza ad aumentare il proprio fascino nella fase del corteggiamento, o perch´e piccole scoperte riguardanti il partner possano avere conseguenze (positive o negative) sorprendentemente grandi (catastrofi). Coppie di individui insicuri hanno invece una decisa propensione ad interrompere la relazione dopo un certo tempo. Infine, si scopre che regimi sentimentali altalenanti sono possibili a causa della copresenza di insicurezza e sinergismo e che le crisi ricorrenti possono lentamente sparire o attenuandosi o rarefacendosi nel tempo. In conclusione, per mezzo di questi modelli, propriet`a come quelle appena descritte, note agli psicanalisti che le hanno scoperte esercitando la loro professione, sono finalmente capite e spiegate: un risultato di indubbio valore. Tutti i fenomeni sopra citati riguardano coppie estremamente semplici, in cui l’evoluzione della storia d’amore `e dominata dalle interazioni tra i partner. Ma nella realt`a le relazioni interpersonali sono molto pi`u complesse perch´e risentono anche dell’ambiente sociale in cui la coppia vive. Successi e insuccessi nella pro- fessione, problemi di salute, lunghi e ripetuti periodi di assenza forzata, esistenza di importanti passioni, come quelle tipiche degli artisti, sono tutti fattori che in- terferiscono, anche notevolmente, con l’evoluzione dei sentimenti. Per modellizzare coppie cos`ı complesse, `e necessario far uso di modelli con tre o pi`u equazioni diffe- renziali, che possono essere analizzati solo per via numerica. Tali modelli possono spiegare anche regimi sentimentali caotici e, quindi, imprevedibili. Finora ci`o `e stato fatto solo per un numero limitato di casi, in particolare per relazioni tenden- zialmente instabili come quelle triangolari. Tuttavia, i risultati ottenuti sono cos`ı incoraggianti da far pensare che l’intero settore scientifico debba, in tempi brevi, espandersi significativamente. Il lettore che desideri approfondire quanto esposto in questo articolo potr`a fare riferimento al libro ”Modeling Love Dynamics”, pubblicato nel 2016 daWorld Scien- tific (autori: Sergio Rinaldi, Fabio Della Rossa, Fabio Dercole, Alessandra Gragnani e Pietro Landi). A chi sia invece interessato a una sintesi dell’argomento e a un breve commento sul senso e sul valore di questi studi si consigliano le seguenti rasse- gne critiche: “The equations of love”, di Marten Scheffer (http://blogs.nature. com/aviewfromthebridge/2016/05/20/the-equations-of-love), “A review of the book Modeling Love Dynamics”, di Gustav Feichtinger (http://www.oegor. at/files/news/news24.pdf) e “Perch`e Rossella O’Hara ha fallito? Se l’amore `e matematico”, di Anna Meldolesi (https://goo.gl/OjpKtD)

Conflicts among N armed groups: Scenarios from a new descriptive model

In this paper we propose and analyze a new descriptive model of armed conflicts among N groups. The model is composed of N2 ordinary differential equations, with 3(N2+N) constant parameters that describe military characteristics and recruitment policies, ranging from pure defensivism to pure fanaticism. The results are only preliminary, but point out interesting (though not very surprising) properties: periodic coexistence is possible, and multiple attractors can exist; governmental groups cannot go extinct if they are highly defensivist, and rebels cannot be eradicated if they are highly fanatic. Shocks due to interventions of short duration of an external army can stabilize/destabilize the system and/or eradicate some group, and the same holds true for small structural changes. Other more subtle questions concerning, for example, the existence of chaotic regimes and the systematic evaluation of the role of strategic factors like power, intelligence, and fanaticism, remain open and require further research

A conceptual model for the prediction of sexual intercourses in permanent couples

The problem of the frequency of sexual intercourses in permanent couples is investigated for the first time with a purely conceptual model. The model, based on a few axioms involving very simple notions like sexual appetite and erotic potential, is composed of two ordinary differential equations which are exactly the same than those proposed almost one century ago in epidemiology. The model can be used to discuss the possibility of estimating strategic parameters from real data, as well as to criticize the rule of "the beans in the yar" proposed in 1970 by David Martin in The Journal of Sex Research

Assessing the reliability and validity of Google Scholar indicators : The case of social sciences in Italy

Google Scholar is an appealing data source for the measurement of scientific production in the social sciences and humanities (SSH) fields. Its appeal derives from its extensive coverage of the literature. This contrasts with issues of data quality, which are still quite controversial. This chapter aims to evaluate the reliability and validity of bibliometric indicators taken from Scholar as well as their coverage of the scientific production in the social sciences. The analysis will be based on a comparison of Scholar with other bibliometric data sources (Web of Science and Scopus) plus an institutional dataset. The reliability of Scholar indicators will be investigated through correlational analysis, while their validity will be assessed using different external criteria (the results of national evaluation procedures based on a peer review approach). The analysis will be developed for the population of Italian university professors in a subset of SSH: political philosophy, history, political science and sociology. The final discussion of the results will take into account the various purposes that bibliometric exercises try to achieve