Conflict, learning, and frustration: a dynamic model of conflict over time

A continuing question in the study of conflict and conflict management is, When is conflict helpful, and when is it harmful? Though many have offered explanations for this (Jehn, Northcraft, & Neale, 1999), data in support of these notions have been less forthcoming, especially in relation to the helpfulness of conflict (De Dreu & Weingart, 2003). In this paper we 2 present a dynamic model of conflict that we hope will both explain and clarify the confusion by conceptualizing conflict as simultaneously containing helpful (learning related) and harmful (negative sentiment related) components. We argue how both learning and negative emotion can inhibit or promote future conflict, constituting feedback loops. We then examine what this implies for conflict over time in terms of the efficacy of collaboration between parties who experience conflict

The Eavesdropper\u27s Dilemma

This paper examines the problem of surreptitious Internet interception from the eavesdropper\u27s point of view. We introduce the notion of fidelity in digital eavesdropping. In particular, we formalize several kinds of network noise that might degrade fidelity, most notably confusion, and show that reliable network interception may not be as simple as previously thought or even always possible. Finally, we suggest requirements for high fidelity network interception, and show how systems that do not meet these requirements can be vulnerable to countermeasures, which in some cases can be performed entirely by a third party without the cooperation or even knowledge of the communicating parties

On the Reliability of Current Generation Network Eavesdropping Tools

This paper analyzes the problem of interception of Internet traffic from the eavesdropper\u27s point of view. We examine the reliability and accuracy of transcripts, and show that obtaining high fidelity transcripts is harder than previously assumed. Even in highly favorable situations, such as capturing unencrypted traffic using standard protocols, simple -- and entirely unilateral -- countermeasures are shown to be sufficient to prevent accurate traffic analysis in many Internet interception configurations. In particular, these countermeasures were successful against every available eavesdropping system we tested. Central to our approach is a new class of techniques that we call confusion, which, unlike cryptography or steganography, does not require cooperation by the communicating parties and, in some case, can be employed entirely by a third party not involved in the communication at all

Assessment of Effects of an Oil Pipeline on Caribou, Rangifer tarandus granti, Use of Riparian Habitats in Arctic Alaska, 2001-2003

Elevated oil field pipelines may alter Caribou (Rangifer tarandus granti) movements and delay or prevent access to insect relief habitat. In an attempt to determine if the 40-km elevated Badami pipeline in northern Alaska changed Caribou use of riparian habitats at the three river crossings where the pipeline is buried, we quantified Caribou habitat use at all three crossings using time-lapse video cameras and aerial distribution surveys over three summers. We compared habitat use, behavior and duration of observations among pipeline and non-pipeline sites. We used a block experimental design with cameras at four sites at the three river crossings to evaluate differences in numbers of Caribou per day at pipeline and non-pipeline sites. At each crossing, four cameras were positioned, with one pair of cameras next to the pipeline (pipeline sites) and one pair of cameras 1.8-3.2 km upstream from the pipeline (non-pipeline sites); where cameras monitored the river bank and channel (river habitat) and the tundra within about 200 m of the river (tundra habitat). Peak numbers of Caribou per day occurred during early July 2003 and mid-July 2001 and 2002. Large numbers of Caribou recorded north of the pipeline during aerial surveys did not usually correspond with increased number per day recorded by cameras suggesting Caribou probably also crossed the pipeline outside of the riparian areas. We assessed local changes in riparian habitat use by comparing the numbers of Caribou per day in river and tundra habitats at pipeline and non-pipeline sites and found no difference. We assessed regional changes in riparian habitat use by comparing numbers of Caribou per day at pipeline sites and at non-pipeline sites and found no difference. Caribou groups spent an average of 1 minute longer at tundra pipeline sites and groups spent 30 seconds longer feeding and trotting at pipeline sites, but these differences were not significant

Agree or not agree? The role of cognitive and affective processes in group disagreements

We develop and test a theoretical framework for understanding how cognitive and affective processes (cognitive and affective integration) influence the way in which disagreements (task and process) among group members affect their performance (individual and group level performance). We use this framework to explain how and why diversity may be either beneficial or detrimental to group process and outcomes. Specifically, we examine how group faultlines may hinder members\u27 ability to create a shared understanding of the problem (cognitive integration) and a shared motivation to synthesize their knowledge (affective integration). If this happens, then groups will fail to share and process information, which will hinder group performance and satisfaction. We test this theory on 321MBA students in 88 five to six person teams from a prestigious East Coast university

Security Protocols With Isotropic Channels

We investigate the security properties of isotropic channels, broadcast media in which a receiver cannot reliably determine whether a message originated from any particular sender and a sender cannot reliably direct a message away from any particular receiver. We show that perfect isotropism implies perfect (information-theoretic) secrecy, and that asymptotically close to perfect secrecy can be achieved on any channel that provides some (bounded) uncertainty as to sender identity. We give isotropic security protocols under both passive and active adversary models, and discuss the practicality of realizing isotropic channels over various media

Sensor Network Security: More Interesting Than You Think

With the advent of low-power wireless sensor networks, a wealth of new applications at the interface of the real and digital worlds is emerging. A distributed computing platform that can measure properties of the real world, formulate intelligent inferences, and instrument responses, requires strong foundations in distributed computing, artificial intelligence, databases, control theory, and security. Before these intelligent systems can be deployed in critical infrastructures such as emergency rooms and powerplants, the security properties of sensors must be fully understood. Existing wisdom has been to apply the traditional security models and techniques to sensor networks. However, sensor networks are not traditional computing devices, and as a result, existing security models and methods are ill suited. In this position paper, we take the first steps towards producing a comprehensive security model that is tailored for sensor networks. Incorporating work from Internet security, ubiquitous computing, and distributed systems, we outline security properties that must be considered when designing a secure sensor network. We propose challenges for sensor networks – security obstacles that, when overcome, will move us closer to decreasing the divide between computers and the physical world

Dynamic Responses of Calving Caribou to Oilfields in Northern Alaska

Past research has suggested that during the calving period, caribou (Rangifer tarandus) in Arctic Alaska generally avoid areas within 1 km of oilfield roads with traffic. However, avoidance is not absolute, and caribou may habituate to infrastructure (e.g., buildings, roads, well pads) and human activity. We conducted road-based surveys of caribou in oilfields on Alaska’s Arctic Coastal Plain during the late calving and post-calving periods of June in 2000–02. We recorded location, composition, and behavior of caribou groups located less than 1 km from active gravel roads and production pads. Caribou groups with calves were on average distributed farther from oilfield infrastructure than were groups without calves, but habituation to oilfield activities, indicated by decreased avoidance, occurred at similar rates for groups with and without calves. During the calving period, sighting rates were greater in areas of low human activity, and calf percentages tended to be greater at night when oilfield activity was reduced. Caribou groups were on average closer to infrastructure during the post-calving periods than during the calving periods in 2000 and 2001, but not in 2002. In 2002, when snow melted early, caribou groups were closer to infrastructure during the calving period than in 2000 and 2001, when snow melted later, emphasizing the importance of examining environmental variables when investigating the dynamic interactions of caribou and oilfields. Overall, caribou appeared to habituate to active oilfield infrastructure after the calving period in 2000, late in the calving period in 2001, and likely before our sampling period in 2002. The timing of annual rehabituation was positively correlated with timing of spring snowmelt. Land and wildlife managers can use information from this study to develop calving period-specific mitigation measures that are more effective and flexible.Selon des recherches antérieures, pendant sa période de vêlage, le caribou (Rangifer tarandus) de l’Alaska arctique évite généralement les régions se trouvant à l’intérieur d’un kilomètre des routes où circulent des véhicules menant aux chantiers pétroliers. Cependant, cet évitement n’est pas absolu, et le caribou peut s’accoutumer aux infrastructures (comme les bâtiments, les routes et les chantiers) et à l’activité humaine. Nous avons effectué le dénombrement des caribous près des routes des champs de pétrole de la plaine côtière arctique de l’Alaska vers la fin de la période de vêlage et après la période de vêlage de juin 2000 à 2002. Nous avons consigné l’emplacement, la composition et le comportement des groupes de caribous se trouvant à moins d’un kilomètre des routes de gravier et des chantiers de production en activité. En moyenne, les caribous qui avaient des petits se tenaient plus loin des infrastructures pétrolières que les groupes de caribous qui n’avaient pas de petits. Cela dit, l’accoutumance aux activités pétrolières, dénotée par un moins grand évitement, survenait à des taux semblables pour les groupes qui avaient des petits et les groupes qui n’en avaient pas. Pendant la période de vêlage, les taux d’observation de caribous étaient plus élevés dans les régions où il y avait peu d’activité humaine, et les pourcentages de petits avaient tendance à être plus élevés la nuit, lorsqu’il y avait peu de va-et-vient aux chantiers. En moyenne, les groupes de caribous s’approchaient plus des infrastructures pendant les périodes suivant le vêlage des années 2000 et 2001, mais pas en 2002. En 2002, quand la neige a fondu plus tôt que d’habitude, les groupes de caribous s’approchaient plus des infrastructures pendant la période de vêlage qu’en 2000 et 2001, lorsque la neige a fondu plus tard. Cela fait ressortir l’importance de tenir compte des variables environnementales lorsque nous faisons des enquêtes sur les interactions dynamiques entre les caribous et les champs de pétrole. Dans l’ensemble, les caribous semblaient s’accoutumer aux infrastructures pétrolières en activité après la période de vêlage en 2000, puis vers la fin de la période de vêlage en 2001, et vraisemblablement avant notre période d’échantillonnage en 2002. Le moment de l’accoutumance annuelle coïncidait positivement avec le moment de la fonte des neiges au printemps. Les gestionnaires des terres et de la faune peuvent se servir de l’information émanant de cette étude pour élaborer des mesures d’atténuation tenant compte de la période de vêlage, mesures qui sont plus efficaces et qui présentent plus de souplesse

Caribou Distribution During the Post-calving Period in Relation to Infrastructure in the Prudhoe Bay Oil Field, Alaska

There is concern that caribou (Rangifer tarandus) may avoid roads and facilities (i.e. infrastructure) in the Prudhoe Bay oil field (PBOF) in northern Alaska, and that this avoidance can have negative effects on the animals. We quantified the relationship between caribou distribution and PBOF infrastructure during the post-calving period (mid-June to mid-August) with aerial surveys from 1990 to 1995. We conducted four to eight surveys per year with complete coverage of the PBOF. We identified active oil field infrastructure and used a geographic information system (GIS) to construct ten 1 km wide concentric intervals surrounding the infrastructure. We tested whether caribou distribution is related to distance from infrastructure with a chi-squared habitat utilization-availability analysis and log-linear regression. We considered bull, calves, and total caribou of all sex/age classes separately. The habitat utilization-availability analysis indicated there was no consistent trend of attraction to or avoidance of infrastructure. Caribou frequently were more abundant than expected in the intervals close to infrastructure, and this trend was more pronounced for bulls and for total caribou of all sex/age classes than for calves. Log-linear regression (with Poisson error structure) of numbers of caribou and distance from infrastructure were also done, with and without combining data into the 1 km distance intervals. The analysis without intervals revealed no relationship between caribou distribution and distance from oil field infrastructure, or between caribou distribution and Julian date, year, or distance from the Beaufort Sea coast. The log-linear regression with caribou combined into distance intervals showed the density of bulls and total caribou of all sex/age classes declined with distance from infrastructure. Our results indicate that during the post-calving period: 1) caribou distribution is largely unrelated to distance from infrastructure; 2) caribou regularly use habitats in the PBOF; 3) caribou often occur close to infrastructure; and 4) caribou do not appear to avoid oil field infrastructure.On s'inquiète du fait que le caribou (Rangifer tarandus) pourrait éviter les routes et installations (c-à-d. les infrastructures) du champ pétrolifère de Prudhoe Bay dans l'Alaska septentrional et que ce comportement pourrait avoir des répercussions négatives sur les animaux. Des relevés aériens effectués de 1990 à 1995 ont permis de quantifier le rapport entre la distribution du caribou et les infrastructures du champ pétrolifère de Prudhoe Bay au cours de la période suivant immédiatement la mise bas (de mi-juin à mi-août). On a procédé à un nombre de relevés annuels allant de quatre à huit, couvrant toute la superficie du champ. On a identifié les infrastructures du champ pétrolifère qui étaient en activité et utilisé un système d'information géographique (SIG) pour construire dix anneaux concentriques de 1 km de large entourant chaque infrastructure. On a testé l'hypothèse que la distribution du caribou est indépendante de l'éloignement de l'infrastructure grâce au test de chi carré entre l'utilisation et la disponibilité de l'habitat, et à la régression log-linéaire. On a tenu compte séparément de la catégorie des mâles, de celle des veaux et de celle de la population totale, sexe et âge confondus. L'analyse de l'utilisation et de la disponibilité de l'habitat révélait qu'il n'y avait pas de schéma cohérent d'attrait ou d'évitement des infrastructures. Les caribous étaient souvent plus abondants que prévu dans les anneaux proches des infrastructures, et cette tendance était plus prononcée pour les mâles adultes et pour l'ensemble des catégories, sexe et âge confondus, que pour les veaux. On a fait les analyses par régression log-linéaire en regroupant et sans regrouper les données anneaux de 1 km de largeur. L'analyse sans regroupement montrait qu'il n'existe pas de rapport entre la distribution du caribou et l'éloignement des infrastructures du champ pétrolifère, ou entre la distribution du caribou et la date julienne ou même l'éloignement de la côte de la mer de Beaufort. L'analyse log-linéaire avec les caribous regroupés dans des anneaux concentriques montrait que la densité des mâles adultes de l'ensemble de la population, sexe et âge confondus, était plus élevée dans les anneaux jouxtant les infrastructures. Nos résultats indiquent que, durant la période suivant immédiatement la mise bas: (1) la distribution du caribou est dans une large mesure indépendante de l'éloignement des infrastructures; (2) le caribou utilise les habitats au sein du champ pétrolifère de Prudhoe Bay sur une base régulière; (3) le caribou se trouve fréquemment près des infrastructures; et (4) le caribou ne semble pas chercher à éviter les infrastructures du champ pétrolifère

Best practices for MRI systematic reviews and metaâ analyses

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149543/1/jmri26198.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149543/2/jmri26198_am.pd