Modelling the structural behaviour of rammed earth components

Proceedings of the Twelfth International Conference on Computational Structures Technology, B.H.V. Topping and P. Iványi, (Editors), Civil-Comp Press, Stirlingshire, Scotland.The rammed earth technique has a significant presence in the earthen built heritage, where was used to build from simple dwellings to fortresses. However, the high vulnerability of rammed earth construction to decay agents and to seismic events puts at risk their further existence and the lives of millions of people. With respect to the seismic behaviour of rammed earth walls, the understanding and modelling of their shear behaviour are topics rarely approached in literature. Nevertheless, these topics are of significant importance in the preservation and strengthening of rammed earth constructions. This paper presents experimental and numerical work where the shear behaviour of unstabilised rammed earth is analysed. The experimental program consisted in the testing of several unstabilised rammed earth wallets subject to diagonal compression, which allowed a better understanding of the shear behaviour of unstabilised rammed earth. The numerical work consists of the modelling, of the previous tests, using the finite element method and by considering both the macroand micro-modelling approaches. In general, the numerical models showed a good agreement with the experimental results.The authors would like to thank gratefully the funding provided by the Portuguese Science and Technology Foundation through project FCOMP-01-0124-FEDER-028864 (FCT-PTDC/ECM-EST/2396/2012). Furthermore, the authors wish to express their gratitude to Júlio Machado for his valuable help in the experimental program.info:eu-repo/semantics/publishedVersio

Organizational Commitment: The Mediator for Work Motivation and Organizational Climate Toward Organizational Citizenship Behavior (OCB)

The aim of this research is to know and analyse the role of mediated organizational commitment in determining work motivation, and organizational climate toward Organizational Citizenship Behaviour (OCB) of the employee at PT. Banoli Motor Denpasar. Census method is used in this research, where all the staff in total 76 people regarded as the sample. The data collected were then analysed further using structural equation modelling (SEM Analysis) with PLS technique. The findings of this research are; that work motivation has a positive and significant correlation towards organizational commitment, organizational climate contributes positively and significantly toward organizational commitment, work motivation does not significantly correlate toward OCB, organizational climate and organizational commitment have a significant and positive correlation toward OCB. Organizational commitment is proven as a full mediation between work motivation and OCB, and a partial mediation among organizational climate and OCB. These findings mean that mediation of organizational commitment can be the determinant on the indirect effect of work motivation toward OCB, and organizational climate toward OCB at PT. Banoli Motor’s staff Denpasar. Keywords: work motivation, organizational climate, organizational commitment, OCB, SEM-PL

Estimating Spatio-Temporal Risks from Volcanic Eruptions using an Agent-Based Model

Managing disasters caused by natural events, especially volcanic crises, requires a range of approaches, including risk modelling and analysis. Risk modelling is commonly conducted at the community/regional scale using GIS. However, people and objects move in response to a crisis, so static approaches cannot capture the dynamics of the risk properly, as they do not accommodate objects’ movements within time and space. The emergence of Agent-Based Modelling makes it possible to model the risk at an individual level as it evolves over space and time. We propose a new approach of Spatio-Temporal Dynamics Model of Risk (STDMR) by integrating multi-criteria evaluation (MCE) within a georeferenced agent-based model, using Mt. Merapi, Indonesia, as a case study. The model makes it possible to simulate the spatio-temporal dynamics of those at risk during a volcanic crisis. Importantly, individual vulnerability is heterogeneous and depends on the characteristics of the individuals concerned. The risk for the individuals is dynamic and changes along with the hazard and their location. The model is able to highlight a small number of high-risk spatio-temporal positions where, due to the behaviour of individuals who are evacuating the volcano and the dynamics of the hazard itself, the overall risk in those times and places is extremely high. These outcomes are extremely relevant for the stakeholders, and the work of coupling an ABM, MCE, and dynamic volcanic hazard is both novel and contextually relevant

Social agents?:A systematic review of social identity formalizations

Simulating collective decision-making and behaviour is at the heart of many agent-based models (ABMs). However, the representation of social context and its influence on an agent’s behaviour remains challenging. Here, the Social Identity Approach (SIA) from social psychology, offers a promising explanation, as it describes how people behave while being part of a group, how groups interact and how these interactions and ingroup norms can change over time. SIA is valuable for various application domains while also being challenging to formalise. To address this challenge and enable modellers to learn from existing work, we took stock of ABM formalisations of SIA and present a systematic review of SIA in ABMs. Our results show a diversity of application areas and formalisations of (parts of) SIA without any converging practice towards a default formalisation. Models range from simple to (cognitively) rich, with a group of abstract models in the tradition of opinion dynamics employing SIA to specify group-based social influence. We also found some complex cognitive SIA formalisations incorporating contextual behaviour. When considering the function of SIA in the models, representing collectives, modelling group-based social influence and unpacking contextual behaviour all stood out. Our review was also an inventory of the formalisation challenge attached to using a very promising socialpsychological theory in ABMs, revealing a tendency for reference to domain-specific theories to remain vague

Does courier gender matter? Exploring mode choice behaviour for E-groceries crowd-shipping in developing economies

This paper examines the mode choice behaviour of people who may act as occasional couriers to provide crowd-shipping (CS) deliveries. Given its recent increase in popularity, online grocery services have become the main market for crowd-shipping deliveries' provider. The study included a behavioural survey, PTV Visum simulations and discrete choice behaviour modelling based on random utility maximization theory. Mode choice behaviour was examined by considering the gender heterogeneity of the occasional couriers in a multimodal urban transport network. The behavioural dataset was collected in the city of Kharkiv, Ukraine, at the beginning of 2021. The results indicated that women were willing to provide CS service with 8% less remuneration than men. Women were also more likely to make 10% longer detours by car and metro than men, while male couriers were willing to implement 25% longer detours when travelling by bike or walking. Considering the integration of CS detours into the couriers' routine trip chains, women couriers were more likely to attach the CS trip to the work-shopping trip chain whilst men would use the home-home evening time trip chain. The estimated marginal probability effect indicated a higher detour time sensitivity with respect to expected profit and the relative detour costs of the couriers

Understanding post-earthquake hospital arrival times through agent-based modelling

Infrastructural and socio-economic factors controlling the post-earthquake transfer of injured people to hospitals are critical for decision-making on post-disaster medical assistance but remain largely unexplored in the literature. This work addresses this challenge through an agent-based modelling approach that comprises two computational steps (modules). The first module consists of a probabilistic multi-severity casualty estimation model for quantifying the number, severity, and distribution of casualties following an earthquake in a region. The second module incorporates an agent-based model simulating individual and collective community behaviour related to transporting injured people to hospitals during the post-disaster phase. The model assumes that injured people arrive at hospitals by their own means (in a vehicle) or by ambulance, depending on the severity of their injury. The proposed approach is demonstrated for a moment magnitude (Mw) 8.0 earthquake scenario earthquake in Lima, Peru, focusing on two districts (i.e., Santiago de Surco, San Juan de Miraflores). The main results of this study indicate that some characteristics of the built environment (i.e., the number of hospitals and ambulances in the area) and attributes of the population (i.e., car ownership) may be essential for guaranteeing access to adequate post-disaster medical care. The findings of this work can be used to help decision-makers in planning effective emergency response strategies for future earthquake disasters

STREETS: an agent-based pedestrian model.

8-11 Septembe

From individual characters to large crowds: augmenting the believability of open-world games through exploring social emotion in pedestrian groups

Crowds of non-player characters improve the game-play experiences of open-world video-games. Grouping is a common phenomenon of crowds and plays an important role in crowd behaviour. Recent crowd simulation research focuses on group modelling in pedestrian crowds and game-designers have argued that the design of non-player characters should capture and exploit the relationship between characters. The concepts of social groups and inter-character relationships are not new in social psychology, and on-going work addresses the social life of emotions and its behavioural consequences on individuals and groups alike. The aim of this paper is to provide an overview of current research in social psychology, and to use the findings as a source of inspiration to design a social network of non-player characters, with application to the problem of group modelling in simulated crowds in computer games

Prospects for large-scale financial systems simulation

As the 21st century unfolds, we find ourselves having to control, support, manage or otherwise cope with large-scale complex adaptive systems to an extent that is unprecedented in human history. Whether we are concerned with issues of food security, infrastructural resilience, climate change, health care, web science, security, or financial stability, we face problems that combine scale, connectivity, adaptive dynamics, and criticality. Complex systems simulation is emerging as the key scientific tool for dealing with such complex adaptive systems. Although a relatively new paradigm, it is one that has already established a track record in fields as varied as ecology (Grimm and Railsback, 2005), transport (Nagel et al., 1999), neuroscience (Markram, 2006), and ICT (Bullock and Cliff, 2004). In this report, we consider the application of simulation methodologies to financial systems, assessing the prospects for continued progress in this line of research

Towards the Development of a Simulator for Investigating the Impact of People Management Practices on Retail Performance

Often models for understanding the impact of management practices on retail performance are developed under the assumption of stability, equilibrium and linearity, whereas retail operations are considered in reality to be dynamic, non-linear and complex. Alternatively, discrete event and agent-based modelling are approaches that allow the development of simulation models of heterogeneous non-equilibrium systems for testing out different scenarios. When developing simulation models one has to abstract and simplify from the real world, which means that one has to try and capture the 'essence' of the system required for developing a representation of the mechanisms that drive the progression in the real system. Simulation models can be developed at different levels of abstraction. To know the appropriate level of abstraction for a specific application is often more of an art than a science. We have developed a retail branch simulation model to investigate which level of model accuracy is required for such a model to obtain meaningful results for practitioners.Comment: 24 pages, 7 figures, 6 tables, Journal of Simulation 201