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Abstract: Agent-based modeling is an approach based on the idea that a system is composed of decentralized individual “agents” and that each agent interacts with other agents according to localized knowledge. Special kinds of artificial agents are the agents created by analogy with social insects. Social insects (bees, wasps, ants, and termites) have lived on Earth for millions of years. Their behavior is primarily characterized by autonomy, distributed functioning, and self-organizing capacities. Social insect colonies teach us that very simple organisms can form systems capable of performing highly complex tasks by dynamically interacting with each other. Swarm intelligence is the branch of artificial intelligence based on study of behavior of individuals in various decentralized systems. The paper presents a classification and analysis of the results achieved using swarm intelligence (SI) to model complex traffic and transportation processes. The primary goal of this paper is to acquaint readers with the basic principles of Swarm Intelligence, as well as to indicate potential swarm intelligence applications in traffic and transportation. [Copyright &y& Elsevier]

Abstract: A mathematical formulation of column optimization problems allowing for bimodal optimum buckling loads is developed in this paper. The columns are continuous and linearly elastic, and assumed to have no geometrical imperfections. It is first shown that bimodal solutions exist for columns that rest on a linearly elastic (Winkler) foundation and have clamped-clamped and clamped-simply supported ends. The equilibrium equation for a non-extensible, geometrically nonlinear elastic column is then derived, and the initial post-buckling behaviour of a bimodal optimum column near the bifurcation point is studied using a perturbation method. It is shown that in the general case the post-buckling behaviour is governed by a fourth order polynomial equation, i.e., near the bifurcation point there may be up to four post-buckling equilibrium states emanating from the trivial equilibrium state. Each of these equilibrium states may be either supercritical or subcritical in the vicinity of the bifurcation point. The conditions for stability of these non-trivial post-buckling states are established based on verification of positive semi-definiteness of a two-by-two matrix whose coefficients are integrals of the buckling modes and their derivatives. In the end of the paper we present and discuss numerical results for the post-buckling behaviour of several columns with bimodal optimum buckling loads. [Copyright &y& Elsevier]

Abstract: Drinking and driving road checks are often organized with either a clear prevention or repression objective in mind. The objective of a prevention strategy is to make as many people as possible believe that police officers are enforcing drinking and driving laws and that drinking drivers will most likely be caught. As such, targeting high traffic count road sites with high-visibility road checks is a priority because it serves to increase awareness of the enforcement activity. An alternative to this prevention approach is the “repression” approach that involves targeting times and places where the highest number of drinking drivers are to be expected. Rather than attempting to affect the subjective chance of getting caught, this approach seeks to increase the objective likelihood of getting caught; the aim is to apprehend as many drinking drivers as possible. Regardless of the chosen strategy, there is a need to understand how traffic count influences drinking and driving behaviour as traffic count may play a role in a police officer''s choice of sites for a road check. The objective of this paper is to shed some light on this relationship between drinking and driving behaviour and traffic count. In this paper, data from a roadside survey, carried out in British Columbia in 2003, are used. A two-level logistic regression analysis was carried out with data from 2627 drivers coming from 48 different road sites to replicate a model that was previously obtained with comparable data from a Belgian roadside survey, also carried out in 2003. The present study successfully replicated the findings of the Belgian model, substantiating that the probability for drivers to be drinking and driving significantly decreases with an increasing level of traffic count. This supports the suggestion that drinking drivers avoid high traffic count road sites. The relevance of these findings with respect to organizing preventive or repressive road checks and possible confounding variables are discussed at the end of this paper. [Copyright &y& Elsevier]

Abstract: This paper presents the methodology and results of estimation of an integrated driving behavior model that attempts to integrate various driving decisions. The model explains lane changing and acceleration decisions jointly and so, captures inter-dependencies between these behaviors and represents drivers’ planning capabilities. It introduces new models that capture drivers’ choice of a target gap that they intend to use in order to change lanes, and acceleration models that capture drivers’ behavior to facilitate the completion of a desired lane change using the target gap. The parameters of all components of the model are estimated simultaneously with the maximum likelihood method and using detailed vehicle trajectory data collected in a freeway section in Arlington, Virginia. The estimation results are presented and discussed in detail. [Copyright &y& Elsevier]

Abstract: Ground characterization and ground behavior evaluation are introductory steps in tunnel design. For a realistic evaluation reflecting specific ground and site conditions, reasonable ground models and evaluation tools are essential. At design stage simulations with discrete element method enables to model the reaction of blocky rock masses during excavation. At construction stage the predicted model is updated according to the absolute displacement monitoring data. In this paper a parametric study is performed with distinct element program UDEC for different joint characteristics and in situ stresses to evaluate the ground behavior in blocky rock masses. The classification of the ground behaviors are carried out according to the established delimiting criteria. Characteristics of various ground behaviors and conditions leading to the specified behavior are defined. [Copyright &y& Elsevier]

Abstract: Existing models that integrate emotion and cognition generally do not fully specify why cognition needs emotion and conversely why emotion needs cognition. In this paper, we present a unified computational model that combines an abstract cognitive theory of behavior control (PEACTIDM) and a detailed theory of emotion (based on an appraisal theory), integrated in a theory of cognitive architecture (Soar). The theory of cognitive control specifies a set of required computational functions and their abstract inputs and outputs, while the appraisal theory specifies in more detail the nature of these inputs and outputs and an ontology for their representation. We argue that there is a surprising functional symbiosis between these two independently motivated theories that leads to a deeper theoretical integration than has been previously obtained in other computational treatments of cognition and emotion. We use an implemented model in Soar to test the feasibility of the resulting integrated theory, and explore its implications and predictive power in several task domains. [Copyright &y& Elsevier]

Abstract: In a context in which aggressive behavior has been predominantly predicted by self-reports, this paper considers how a theoretical and empirical examination of automatic and deliberative processes in information processing and decision making may contribute to our understanding of aggressive behavior. We review research devoted to distinguishing two types of aggression with regard to the level of automaticity or control they involve, a distinction similar to the one between automatic and deliberative processes. In parallel with this theoretical distinction, implicit measures appear to be a good candidate for measuring aggression and predicting aggressive behavior. Although consideration of automatic processes is essential for a better understanding of how and why people act aggressively, it should not lead to the conclusion that aggressive behavior is fully automatic. This contribution underlines that the interaction between environment and individual differences is the key element at the implicit level, as it is at the explicit level. Some future directions for studying aggression using implicit measures are drawn. [Copyright &y& Elsevier]

Abstract: In this paper, a new type of green reactive powder concrete (GRPC) with compressive strength of 200MPa (C200 GRPC) is prepared by utilizing composite mineral admixtures, natural fine aggregates, short and fine steel fibers. The quasi-static mechanical properties (mechanical strength, fracture energy and fiber–matrix interfacial bonding strength) of GRPC specimens, cured in three different types of regimes (standard curing, steam curing and autoclave curing), are investigated. The experimental results show that the mechanical properties of the C200 GRPC made with the cementitious materials consisting of 40% of Portland cement, 25% of ultra fine slag, 25% of ultra fine fly ash and 10% of silica fume, 4% volume fraction of steel fiber are higher than the others. The corresponding compressive strength, flexural strength, fracture energy and fiber–matrix interfacial bonding strength are more than 200MPa, 60MPa, 30,000J/m2 and 14MPa, respectively. The dynamic tensile behavior of the C200 GRPC is also investigated through the Split Hopkinson Pressure Bar (SHPB) according to the spalling phenomena. The dynamic testing results demonstrate that strain rate has an important effect on the dynamic tensile behavior of C200 GRPC. With an increase of strain rate, the peak stress rapidly increases in the dynamic tensile stress–time curves. The C200 GRPC exhibits an obvious strain rate stiffening effect in the case of high strain rate. Finally, the mechanism of excellent static and dynamic properties gains of C200 GRPC is also discussed. [Copyright &y& Elsevier]

Abstract: This paper presents the experimental analysis of a tensegrity structure based on truncated icosahedron geometry. The objective of the study is to characterize the mechanical behavior of a tensegrity dome. Two reduced scale tensegrity domes were assembled, one of which was instrumented for the laboratory experiments. The experimental data collected are related with structural displacements, strain in the bars and strain in the cables. [Copyright &y& Elsevier]

Abstract: The behaviour in terms of robustness during turn-off of power IGBT modules is presented. The experimental characterisation is aimed to identify the main limits during turn-off in power IGBT modules in typical hard switching applications. In this paper an experimental characterization of high power IGBT modules at output currents beyond RBSOA, at high junction temperatures and under different driving conditions is presented. Several devices of different generations, current and voltage ratings have been considered. The experimental characterisation has been performed by means of a non-destructive experimental set-up where IGBT modules are switched in presence of a protection circuit that is able to prevent device failure at the occurrence of any possible instable behaviour. The experimental analysis confirms the very good robustness of high power IGBT modules which can withstand large current overstress well beyond the declared RBSOA limits even at temperatures larger than those one declared by manufacturers. A comparison between IGBT device generation is also presented. [Copyright &y& Elsevier]

Abstract: Intermittently failing IC’s are difficult to debug with techniques such as time resolved photoemission (TRE), that measure internal signals, because the measurements will contain a mixture of passing and failing behaviour. In this paper, we show that by swapping 2 BNC cables on the outside of an Emiscope II TRE instrument, it becomes possible to measure separately both the passing and failing behaviour of an intermittently failing IC. We illustrate the techniques in two case studies. [Copyright &y& Elsevier]

Abstract: This paper focuses on the extraction of sclareol from the leaves of Salvia sclarea Lamiaceae, more commonly known as Clary sage. The process involves the extraction of sclareol using a CO2-soluble GRAS solvent such as ethyl lactate, followed by GAS anti-solvent precipitation from ethyl lactate solution with carbon dioxide. The three-component phase behavior of the sclareol–ethyl lactate–CO2 system at various pressures has been determined and indicates a slight cybotactic effect. The ability of thermodynamic models to predict the complex three-component phase behavior of this system is discussed, together with the implications of the thermodynamic behavior of the system on process design. [Copyright &y& Elsevier]

Abstract: Safe egress is one of the key design issues identified by facility planners, manager and inspectors. Computational tools are now available for the simulation and design of emergency evacuation and egress. However, these tools rely heavily on assumptions about individual human and social behaviors, which have been found to be oversimplified, inconsistent and even incorrect. Furthermore, the behaviors are usually incorporated into the computational model in an ad hoc manner. This paper presents a framework for studying human and social behavior, from the perspectives of human decision-making and social interaction, and for incorporating such behavior systematically in a dynamic computational model suitable for emergency egress analysis. [Copyright &y& Elsevier]

The paper investigates the relationship between social interactions and crime for the case of a developing country that has shown increasing crime rates in recent years. Social interactions are defined as any type of relationship of an individual with other individuals that can affect his/her behavior. We use a unique data set to investigate whether interaction among individuals of the same family and/or a neighborhood or community had any influence on the criminal behavior of individuals who are already convicted. The data set was constructed through interviews at the Papuda State Jail in Brasilia, Brazil. The results are in line with a growing literature on the study of criminal behavior and demonstrate that strengthening family and community relationships can be a desirable way of fighting crime in the context of developing countries. [ABSTRACT FROM AUTHOR]

The importance of attitudes in the relationship between travel behaviour (TB) and the built environment (BE) has been the subject of debate in the literature for about two decades. In line with the Theory of Planned Behaviour, attitudes – which affect behaviour – are generally assumed to be constant. However, it is plausible that attitudes can change, both directly, or indirectly, through the impact of the built environment on travel behaviour, a process which is referred to as reverse causality (RC). Based on literature from social psychology, this paper provides a conceptual model for the explanation of attitude changes. It also reviews the literature in the area of BE and TB concluding that two explanations dominate: a change in attitudes due to new experiences which can be underpinned by learning theories, and a change in attitudes due to mismatches between attitudes and behaviour which can be explained by cognitive dissonance theories. The literature also suggests a few additional explanations, while we also suggest explanations not provided in travel behaviour literature. Finally, we present an agenda for future research. • The built environment can influence attitudes. • Explanations why attitudes change • Overview of theoretical underpinnings • Literature review: dominant role of experiences and cognitive dissonance theory [ABSTRACT FROM AUTHOR]