On the loop space of a 2-category

Every small category $C$ has a classifying space $BC$ associated in a natural way. This construction can be extended to other contexts and set up a fruitful interaction between categorical structures and homotopy types. In this paper we study the classifying space $B_2C$ of a 2-category $C$ and prove that, under certain conditions, the loop space $\Omega_c B_2C$ can be recovered up to homotopy from the endomorphisms of a given object. We also present several subsidiary results that we develop to prove our main theorem.Comment: 21 pages, final version. Section 8 concerning the main theorem was rewritten. In particular, a partial converse for the main theorem was adde

Dynamic allometry in coastal overwash morphology

Allometry refers to a physical principle in which geometric (and/or metabolic) characteristics of an object or organism are correlated to its size. Allometric scaling relationships typically manifest as power laws. In geomorphic contexts, scaling relationships are a quantitative signature of organization, structure, or regularity in a landscape, even if the mechanistic processes responsible for creating such a pattern are unclear. Despite the ubiquity and variety of scaling relationships in physical landscapes, the emergence and development of these relationships tend to be difficult to observe - either because the spatial and/or temporal scales over which they evolve are so great or because the conditions that drive them are so dangerous (e.g. an extreme hazard event). Here, we use a physical experiment to examine dynamic allometry in overwash morphology along a model coastal barrier. We document the emergence of a canonical scaling law for length versus area in overwash deposits (washover). Comparing the experimental features, formed during a single forcing event, to 5 decades of change in real washover morphology from the Ria Formosa barrier system, in southern Portugal, we find differences between patterns of morphometric change at the event scale versus longer timescales. Our results may help inform and test process-based coastal morphodynamic models, which typically use statistical distributions and scaling laws to underpin empirical or semi-empirical parameters at fundamental levels of model architecture. More broadly, this work dovetails with theory for landscape evolution more commonly associated with fluvial and alluvial terrain, offering new evidence from a coastal setting that a landscape may reflect characteristics associated with an equilibrium or steady-state condition even when features within that landscape do not.Funding Agency NERC Natural Environment Research Council NE/N015665/2 Leverhulme Trust RPG-2018-282info:eu-repo/semantics/publishedVersio

Structured Deformations of Continua: Theory and Applications

The scope of this contribution is to present an overview of the theory of structured deformations of continua, together with some applications. Structured deformations aim at being a unified theory in which elastic and plastic behaviours, as well as fractures and defects can be described in a single setting. Since its introduction in the scientific community of rational mechanicists (Del Piero-Owen, ARMA 1993), the theory has been put in the framework of variational calculus (Choksi-Fonseca, ARMA 1997), thus allowing for solution of problems via energy minimization. Some background, three problems and a discussion on future directions are presented.Comment: 11 pages, 1 figure, 1 diagram. Submitted to the Proceedings volume of the conference CoMFoS1

Bicycle Solutions in Mountain Cities: CycloCable® in Trondheim-Norway

With the rising of soft mobility strategies among to the decision-makers regarding the city policies, the urban designers are developing new ways of improving the bicycles using solutions considering the urban spaces. In the particular case of the mountain cities, the bicycle is still seen as a problematic way of transportation, requiring deep transformations of the urban fabric features. This paper presents the case study of the Norwegian city of Trondheim, well-known by its hills, which is an enormous success in terms of bicycle solutions not only among the locals but also among the visitors. The system is called CycloCable® and it is the first cycle lift for collective transportation which aims to help cyclists, who wish to move more easily, to overcome the sleepiest slopes in urban areas. The methodological approach is based on the literature review, in order to identify the characteristics of this system, which could be used in other mountain cities with similar features of the urban fabric.info:eu-repo/semantics/publishedVersio

Unit testing methods for Internet of Things Mbed OS operating system

Abstract. Embedded operating systems for Internet of Things are responsible for managing hardware and software in these systems. From the vast number of IoT operating system projects available, some projects are backed by large companies or institutes and some are developed completely by the open source community. IoT operating system testing focuses on the key features of IoT such as networking and limited resources. In this thesis, problems in Mbed OS operating system testing methods are identified and a unit testing solution is implemented. The implemented unit testing framework allows developers to write and run unit tests. The framework is also integrated into Mbed OS continuous integration to increase test coverage. This thesis shows how functional testing and unit testing are the most common types of testing in open source embedded operating system projects. Mbed OS unit testing framework results shows how running tests on PC platforms is faster than running tests on IoT devices. This framework also enables developers to write unit tests more freely and improve Mbed OS development process. The implemented unit testing framework solved issues in Mbed OS testing but more in depth research is needed to improve testing methods further.Yksikkötestausmenetelmät esineiden internet Mbed OS käyttöjärjestelmälle. Tiivistelmä. Esineiden internettiin tarkoitetut sulautetut käyttöjärjestelmät ovat tarvittavia laitteiston ja sovellusten hallintaan IoT järjestelmissä. Saatavilla olevien IoT käyttöjärjestelmien joukosta osa on suurten yritysten tai instituutioiden tukemia, ja osa on täysin vapaan lähdekoodin yhteisön kehittämiä. IoT käyttöjärjestelmän testaus keskittyy esineiden internetin avainominaisuuksiin kuten verkkotietoliikenteeseen ja rajallisiin resursseihin. Työssä tunnistetaan Mbed OS käyttöjärjestelmän testausmenetelmien ongelmia ja kehitetään yksikkötestaustyökalu. Kehitetty yksikkötestausympäristö mahdollistaa kehittäjille yksikkötestien kirjoittamisen ja ajamisen. Testaustyökalu yhdistetään myös Mbed OS jatkuvan integraation prosessiin testauskattavuuden parantamiseksi. Työssä katsotaan kuinka funktionaaliset testit ja yksikkötestit ovat yleisimmät testityypit avoimen lähdekoodin sulautetuissa käyttöjärjestelmäprojekteissa. Mbed OS yksikkötestaustyökalu näyttää kuinka testien ajaminen PC ympäristössä on nopeampaa kuin IoT laitteissa. Tämä työkalu myös mahdollistaa kehittäjien kirjoittaa yksikkötestejä vapaammin ja siten parantaa kehitysprosessia. Kehitetty yksikkötestaustyökalu ratkaisi Mbed OS testauksen ongelmia, mutta syventävää tutkimusta tarvitaan enemmän testausmenetelmien parantamiseksi edelleen