True Lies

SOCREAL 2013 : 3rd International Workshop on Philosophy and Ethics of Social Reality 2013. Hokkaido University, Sapporo, Japan, 25-27 October 2013. Session 1 : Logic, Knowledge, and Philosophy of Languag

The Dynamics of Group Knowledge and Belief

5th International Workshop On Philosophy and Logic of Social Reality. 15-17 November 2019.Hokkaido University, Sapporo, Japa

Resolving Distributed Knowledge

Distributed knowledge is the sum of the knowledge in a group; what someone who is able to discern between two possible worlds whenever any member of the group can discern between them, would know. Sometimes distributed knowledge is referred to as the potential knowledge of a group, or the joint knowledge they could obtain if they had unlimited means of communication. In epistemic logic, the formula D_G{\phi} is intended to express the fact that group G has distributed knowledge of {\phi}, that there is enough information in the group to infer {\phi}. But this is not the same as reasoning about what happens if the members of the group share their information. In this paper we introduce an operator R_G, such that R_G{\phi} means that {\phi} is true after G have shared all their information with each other - after G's distributed knowledge has been resolved. The R_G operators are called resolution operators. Semantically, we say that an expression R_G{\phi} is true iff {\phi} is true in what van Benthem [11, p. 249] calls (G's) communication core; the model update obtained by removing links to states for members of G that are not linked by all members of G. We study logics with different combinations of resolution operators and operators for common and distributed knowledge. Of particular interest is the relationship between distributed and common knowledge. The main results are sound and complete axiomatizations.Comment: In Proceedings TARK 2015, arXiv:1606.0729

Coalition and coalition announcement logic

Dynamic epistemic logics which model abilities of agents to make various announcements and influence each other’s knowledge have been studied extensively in recent years. Two notable examples of such logics are Group Announcement Logic and Coalition Announcement Logic. They allow us to reason about what groups of agents can achieve through joint announcements in non-competitive and competitive environments. In this paper, we consider a combination of these logics – Coalition and Group Announcement Logic and provide its complete axiomatisation. Moreover, we partially answer the question of how group and coalition announcement operators interact, and settle some other open problems

The Institutional Practice

The nursing home resident of today is old and frail. Despite such a frailty, many residents are hospitalized, often with the intention of life-extension. Furthermore, rates of hospitalization varies considerably between countries, regions and institutions, even within smaller geographical areas. Even though relating to the same structural framework and conditions, distance to hospitals for instance, some nursing homes hospitalize considerably more than others

Effect of Nano silica and salts on CMC/PAC polymer –Bentonite fluid system

Master's thesis in Petroleum engineeringDrilling fluids are an integral part of drilling operations. The quality of the fluid system determines the success of drilling operations. Recently the application of nanotechnology shows positive results in cement, drilling fluid and enhanced oil recovery. However the application of nano technology is not yet fully investigated. This thesis presents the effect of nano silica on CMC based water based bentonite fluid system. The objective was to formulate an optimized nano-additive system, which improves the rheology and filtrate performances of a conventional water based fluid system. Several combinations of brine treated and polymer (CMC and PAC) treated systems were tested. From the overall tests, • The result shows that the mixture of 0,3g Nano silica + 0,5g CMC + 2,5g NaCl +2,5g KCl in bentonite/H2O (25g/500g) was found to be the best fluid system with respect to the desired rheology and fluid loss. • The hydraulics and cutting transport efficiency of the best optimized system was simulated and the result shows improved performance compared with nano free, fluid system. • The viscoelasticity and flow in porous media of the optimal fluid system were also evaluated

Analytical Approach to Describe Properties in Transition Zones Between Ballasted and Non-Ballasted Track

Norway has for a long time used railways as a means of transport. This method of transportation been used to haul raw materials such as wood and ore. Trains have today become competitors to cars and other means of transportation as a way to commute. However, the tracks used when hauling heavy loads are still being used regardless if the train's goods are commuters or raw materials. Heavy freight trains have a relatively low velocity compared with high-speed trains and because of this, ballasted tracks often used in Norway. The increase in commercial use of train transport has lead to a train-velocity increase and as a result of that, development of non-ballasted tracks have therefore become more favorable. The non-ballasted tracks have a higher stiffness than the ballasted, consequently problems arises when the softer ballasted track transitions over to the stiffer non-ballasted track. Because of the difference in stiffness, will there be a point in the track where the stiffness abruptly changes from one stiffness to another. This will cause damages to the rail, track and train if not dealt with carefully. The railway company Bane NOR have therefore published an interest in the topic of equalizing the stiffness in transition zones. Gaining a deeper understanding of what happens during a transition zone is important so that unnecessary track degradation can be prevented. However, because of the scarcity of information about this particular topic, this thesis could be beneficial to the community. Transition zones are usually designed based upon prior experiences, and the construction of the zones are commonly done by subcontractors. Bane NOR is therefore aspiring to acquire theoretical models that can describe the rail behaviour in transition zones. This master's thesis covers the development of an analytical mathematical model that describes the rail's deflection in both ballasted and non-ballasted tracks. The model takes root in an older theory called "beams on elastic foundation" and the "moving force on a beam" problem. Beams on elastic foundation theory is often used in the railway industry to describe the deflection of rails. Furthermore, the numerical analysis software ANSYS, was utilized to generate an animation of the deflection of the rail beam

Work-related risk factors for workplace bullying : The moderating effect of laissez-faire leadership

Workplace bullying has been described as repeated and systematic exposure to negative social acts over time, which the target has difficulties defending against (Einarsen et al., 2020). Previous research has established that bullying in the workplace is related to a wide range of negative outcomes, and bullying has been classified as a more crippling and devastating problem for employees than all other work-related stress put together (Hauge et al., 2010; Wilson, 1991). Yet, the field still lacks systematic and thorough knowledge of the mechanisms that may explain how situational antecedents are related to the occurrence and development of the workplace bullying process. Drawing on the work environment hypothesis, studies have shown that bullying seems to thrive in demanding workplaces where employees experience organizational constraints and contradictory expectations and demands. Furthermore, leadership practices are expected to have a significant impact on the presence of stress at work. For example, poor and destructive leadership has been identified as a root cause of subordinate stress (Kelloway et al., 2005; Skogstad et al., 2014), and may, as such, act as a strong stressor in its own right. However, leaders may also impact the level of stress at work indirectly, either by influencing the opportunities employees have to cope with those stressors present, or by either aggravating or alleviating the stressors already present in the work environment. The main aim of this PhD-project has been to improve our understanding of the phenomenon of workplace bullying, by investigating some mechanisms and conditions which allow bullying to flourish and escalate. The present thesis is comprised of three scientific papers, all of which employ self-report questionnaire data. The overreaching research question in all three papers was whether laissez-faire leadership can act as a moderator in the relationship between various prevailing workplace stressors and subsequent experiences of negative acts and workplace bullying. Moreover, Paper 2 examines the role of the inter-relationship between two prevailing role stressors in the development of workplace bullying, by testing the mediating effect of role conflicts in the relationship between role ambiguity and subsequent exposure to bullying behaviours. In addition, Papers 2 and 3 also investigated the potential buffering effect of transformational leadership, a constructive form of leadership that is in stark contrast to laissez-faire leadership. In paper 1, the main objective was to investigate the prospective relationship between co-worker conflict at time 1 and individuals who self-reported as new victims of bullying two years later, and whether this relationship was exacerbated by the individuals’ reports of laissez-faire leadership behaviour enacted by their immediate supervisor. Results from a logistic regression analysis on a representative sample of Norwegian workers (N = 1772) showed a significant positive relationship between conflict with co-workers and subsequent new victims of workplace bullying. Furthermore, the results showed that this relationship was only present for employees who reported high (vs. low) levels of laissez-faire leadership behaviour from their immediate supervisor. Paper 2 had two main objectives. First, we aimed to investigate the mechanisms through which role stressors lead to workplace bullying, by testing the hypothesis that the impact of role ambiguity on employees’ exposure to negative acts is mediated through their experiences of increased levels of role conflicts. Second, we tested whether laissez-faire leadership exacerbated, while transformational leadership attenuated, this relationship. In this study, we employed a national probability sample of 1,164 Norwegian workers, with three measurements across a 12-month period. The results supported our hypotheses, in that the relationship between employees’ role ambiguity and subsequent exposure to bullying behaviours was mediated by an increase in employees’ experience of role conflicts. Moreover, we found that laissez-faire leadership exacerbated, while transformational leadership attenuated, the indirect relationship between role ambiguity and subsequent exposure to bullying behaviours through role conflicts. Finally, the objective of Paper 3 was to test whether it is possible to detect these mechanisms even on a daily basis. Accordingly, this study investigated the day-to-day relationship between employees’ work pressure and their exposure to bullying-related negative acts and tested the hypotheses that even daily levels of laissez-faire leadership exacerbated while daily levels of transformational leadership attenuated this relationship. Using data from a sample of 61 naval cadets, who completed a daily diary questionnaire on 36 consecutive days (N = 1509 daily observations), we tested the day-to-day relationships between work pressure and exposure to bullying-related negative acts, and the moderating effects of daily transformational and laissez-faire leadership. The results of multilevel analyses showed a positive relationship between daily work pressure and daily exposure to bullying-related negative acts, and a positive moderating effect of daily laissez-faire leadership behaviour. More specifically, our analyses showed that the positive relationship between daily work pressure and daily exposure to bullying-related negative acts was only present on days when the subordinates reported higher levels of laissez-faire behaviour from their immediate leader. Finally, we did not find support for a moderating effect of daily transformational leadership behaviour. Taken together, these findings yield support to the theoretical notion of the work environment hypothesis, in that situational stressors represent prevailing risk factors for individuals to be exposed to negative acts and bullying in the workplace (Einarsen et al., 1994; Leymann, 1996). Moreover, our findings support the theoretical assumption that laissez-faire leadership is an important facilitator in the development of workplace bullying. Indeed, our results indicate that laissez-faire leadership may be of greater consequence in exacerbating the bullying process than transformational leadership is in attenuating the negative consequences of workplace stressors. If leaders neglect their inherent responsibility to adequately address employees’ experiences of stressful situations and ongoing interpersonal conflicts that merit attention, the risk of workplace bullying is likely to increase. Furthermore, our results show the same trends across samples and research designs, thereby strengthening the robustness of our findings. Finally, the results from Paper 2 improve our understanding of the inter-relationship between role ambiguity and role conflict in relation to bullying, by supporting the hypothesis that employees’ experience of role conflicts mediates the role ambiguity-bullying relationship. This finding indicates that role conflicts may be the more proximal, while role ambiguity may be a more distal antecedent of workplace bullying.Doktorgradsavhandlin

Coalition logic with individual, distributed and common knowledge

Coalition logic is currently one of the most popular logics for multi-agent systems. While logics combining coalitional and epistemic operators have received considerable attention, completeness results for epistemic extensions of coalition logic have so far been missing. In this paper we provide several such results and proofs.We prove completeness for epistemic coalition logic with common knowledge, with distributed knowledge, and with both common and distributed knowledge, respectively. Furthermore, we completely characterise the complexity of the satisfiability problem for each of the three logics. We also study logics with interaction axioms connecting coalitional ability and knowledge