This research builds on Implicit Leadership Theory, which suggests that a leader's performance is likely to be higher when there is congruence between a follower's prototype of what a leader should be and his or her perception of the leader's behaviour. The essence of effective leadership, according to this theory, is being seen as a leader by others. Data were collected from 196 leaders and 1,738 followers from 23 countries within Cargill Incorporated, a US food and agricultural multinational. The research was conducted in two phases. During the first phase data were collected on followers' desired leadership values and their perception of their leader's behaviour on the same dimensions. These data were used to compute a congruence score based on a weighted sum of absolute differences. The congruence score data formed the heart of an individualised Leadership Fit Report written for each leader in the study showing the extent of congruence across 21 leadership characteristics (see Appendix A). The second phase of the study focused on a subset of 933 followers from five countries testing the two hypotheses. The two hypotheses in Phase Two were partially supported. The first was that congruence between desired leadership values and perceived behaviour leads to high performance of a leader and incongruence leads to lower performance. The second was that the relationship between congruence and leader performance varied by nationality. The cross-cultural test of Implicit Leadership Theory captured in Hypothesis 2 was particularly important to Cargill because it revealed unique and important differences between the five countries included in the second data set. This study found that the nature of the relationship between congruence and leader performance varies significantly between all five countries. More specifically the data suggests that congruence does not always lead to high performance. This study, albeit exploratory, makes theoretical, methodological and practical contributions in the following ways. i. A cross cultural test of Implicit Leadership Theory in a multinational organisation with a significant sample size. ii. An existing desired leadership values questionnaire was used and developed further to measure leadership values and leader perception. iii. All 196 leaders received a personalised feedback report showing the level of congruence (or degree of fit) for 21 leadership characteristics. iv. A methodological contribution was made by using Polynomial Regression Equations and Response Surface Methodology to measure the nature of the relationship between desired leadership values, perceived behaviour and leaders' performance. Implicit Leadership Theory was shown to be complex yet very relevant to management practice. The research undertaken was exploratory yet it has created the basis for on going discussion.

Football is one of the biggest sports in the world. Professional teams track their player's positions using GPS (Global Positioning System). This report is divided into two parts, both focusing on applying collective motion to football. % The goal of the first part was to both see if a set of cheaper GPS units could be used to analyze the collective motion of a youth football team. 15 football players did two experiments and played three versus three football matches against each other while wearing a GPS. The first experiment measured the player's ability to control the ball while the second experiment measured how well they were able to move together as a team. Different measurements were measured from the match and Spearman correlations were calculated between measurements from the experiments and matches. Players which had good ball control also scored more goals in the match and received more passes. However, they also took the middle position in the field which naturally is a position which receives more passes. Players which were correlated during the team experiment were also correlated with team-members in the match. But, this correlation was weak and the experiment should be done again with more players. The GPS did not work well in the team experiment but have potential to work well in experiments done on a normal-sized football field. % The goal of the second part of the report was to visualize collective motion, more specifically leader-follower relations, in football which can be used as a basis for further research. This is done by plotting the player's positions at each time step to a user interface. Between each player, a double pointed arrow is drawn, where each side of the arrow has a separate color and arrow width. The maximum time lag between the between the two players is shown as the "pointiness" of the arrow while the color of the arrow show the maximum time lag correlation. The user can change the metrics the correlations are based of. As a compliment to the lagged correlation, a lag score is defined which tell the user how strong the lagged correlation is.

This thesis explores the effects of gender-based leader stereotypes on leader-follower relations in terms of the implications of shared identity between the leader and the followers (team and/or gender). Four experiments assessed followers’ attitudes toward their leaders when the leaders’ genders were under conditions of stereotype threat as compared to advantage (Studies 1 and 2), no-threat (Study 3) or control (Study 4). Experimental conditions were invoked using text-based stereotype manipulations. In Study 1 (where stereotypes favoured male leaders, thus implicitly representing threat for females) and Study 2 (where stereotypes manipulated advantage/threat for both genders), undergraduates in mixed-sex teams rated team leaders’ presentations. In Study 3, undergraduates in single-sex teams (under conditions of stereotype threat or no-threat) predicted their team leader’s performance, indicated leader-follower proximity (leader’s prototypicality, leader identification and collective threat), and reported perceived self-efficacy for leadership. Similar measures were obtained in Study 4, where corporate employees selected an effective leader from their work experience, prior to exposure to stereotype manipulations (threat or control). The student studies had three main findings. First, male leaders benefitted from the ratings of high team identifiers (a) in the context of male advantage/ female stereotype threat and (b) when males were under threat relative to the advantage condition. The benefit of team identification was not evident for female leaders. Second, male leaders benefitted from female followers’ ratings under threat compared to the advantage condition. In contrast, female leaders under stereotype threat were downgraded by female followers relative to advantage or no-threat conditions. Third, stereotype threat negatively affected high team identifiers’ self-efficacy for leadership. In the corporate study, male respondents’ choice of an effective leader was more likely to be a male whereas there was no gender difference in the leaders chosen by female respondents. Drawing on role congruity theory and a social identity framework, the thesis analyses and finds evidence suggesting that stereotype threat as collective threat contributed to followers’ relatively negative attitudes toward female leaders in terms of leader-follower relations.

Η παρούσα διπλωματική εργασία ασχολείται με τον συνεργατικό έλεγχο μιας ομάδας αυτόνομων ρομπότ. Θεωρώντας ότι μόνο ένα ρομπότ έχει πλήρη γνώση για το μονοπάτι που επιθυμούμε να ακολουθήσουν τα ρομπότ, θα πρέπει τα υπόλοιπα παίρνοντας μετρήσεις από διάφορους αισθητήρες και ανταλλάσοντας πληροφορίες μεταξύ τους, να σχεδιάζουν και να ακολουθούν τέτοιες τροχιές ώστε να πετύχουν τον στόχο τους. Από τη στιγμή που ένα μοναδικό ρομπότ γνωρίζει το επιθυμητό μονοπάτι, πρόκειται για ένα leader-follower σχηματισμό όπου κάθε ρομπότ καλείται να ακολουθήσει αυτό που προηγείται. Προκειμένου τα ρομπότ να μπορούν να ακολουθήσουν μία τροχιά αναπτύχθηκε σε περιβάλλον LabVIEW ένας ελεγκτής παρακολούθησης τροχιάς. Για την ανταλλαγή πληροφοριών και μηνυμάτων συντονισμού μεταξύ των ρομπότ, αναπτύχθηκε ασύρματο δίκτυο ZigBee. Το πρόβλημα γνώσης σχετικά με το που βρίσκεται ο leader κάθε ρομπότ λύθηκε με τη χρήση αλγορίθμων που επεξεργάζονται τις μετρήσεις των ενσωματωμένων Sonar. Επίσης το πρόβλημα γνώσης του πραγματικού προσανατολισμού κάθε ρομπότ, αντιμετωπίστηκε με την κατασκευή ενός ψηφιακού μαγνητομέτρου. Για κάθε ρομπότ ξεχωριστά, αναπτύχθηκε ο συνεργατικός αλγόριθμος ο οποίος εξασφαλίζει ότι η ομάδα θα πετυχαίνει τον στόχο που έχει αρχικά τεθεί. Τέλος παρουσιάζονται πειραματικά αποτελέσματα για ομάδες δύο και τριών ρομπότ. / The present thesis elaborates on the cooperative control of mobile robots. Assuming that one robot has complete knowledge of the desired path the robotic platoon must follow, a coordination control scheme must be created, based on sensor measurements and platoon communication, that generates desired trajectories for each of the members of the platoon. From the moment a single robot has complete knowledge of the path, the coordination scheme is based on leader-follower formation control. A trajectory tracking controller was developed in LabVIEW, while a ZigBee based wireless network was implemented for the platoon communication. To find the relative position of the leader for each robot, a sonar based localization algorithm was created, with position measurements through the robot’s encoders and orientation given from a magnetometer. For each robot seperately, the coordination algorithm was developed, that ensures that the platoon will achieve the original goal.

abstract: As robotic systems are used in increasingly diverse applications, the interaction of humans and robots has become an important area of research. In many of the applications of physical human robot interaction (pHRI), the robot and the human can be seen as cooperating to complete a task with some object of interest. Often these applications are in unstructured environments where many paths can accomplish the goal. This creates a need for the ability to communicate a preferred direction of motion between both participants in order to move in coordinated way. This communication method should be bidirectional to be able to fully utilize both the robot and human capabilities. Moreover, often in cooperative tasks between two humans, one human will operate as the leader of the task and the other as the follower. These roles may switch during the task as needed. The need for communication extends into this area of leader-follower switching. Furthermore, not only is there a need to communicate the desire to switch roles but also to control this switching process. Impedance control has been used as a way of dealing with some of the complexities of pHRI. For this investigation, it was examined if impedance control can be utilized as a way of communicating a preferred direction between humans and robots. The first set of experiments tested to see if a human could detect a preferred direction of a robot by grasping and moving an object coupled to the robot. The second set tested the reverse case if the robot could detect the preferred direction of the human. The ability to detect the preferred direction was shown to be up to 99% effective. Using these results, a control method to allow a human and robot to switch leader and follower roles during a cooperative task was implemented and tested. This method proved successful 84% of the time. This control method was refined using adaptive control resulting in lower interaction forces and a success rate of 95%. / Dissertation/Thesis / M.S. Mechanical Engineering 2014

A striking feature of swarm robotics is its ability to solve complex tasks through simple local interactions between robots. Those interactions require a good infrastructure in communication and localization. However, in underwater environments, the severe attenuation of radio waves complicates communication and localization of different vehicles. Existing literature on underwater swarms use centralized network topology which require physical vicinity to the central node to ensure reliability. We are interested in building a decentralized underwater swarm with a decentralized network topology that only requires neighbour communication and self-localization. We develop a simple leader-follower interaction rule where the follower estimates the leader's position and acts upon that estimation. The leader shines a 450 nm diffracted blue laser that the follower uses to continuously align its light sensors to the light source. Furthermore, the leader's laser can be modulated for explicit communication purposes. The proposed leader-follower approach produces satisfactory results in surge and sway axes, however, it is not robust against illumination changes in the environment. We then proceed to solve the self-localization problem, by fusing Inertial Measurement Unit (IMU) values with the thrust to estimate a robot’s position. In an Ardusub Simulation in the loop (SITL), the particle filter showed a slightly better performance than the Extended Kalman Filter (EKF) in the surge axis. However, both filters are prone to drifting after a while. We have observed that IMU values need to be filtered properly or another reliable sensor must be used alternatively.

Yes / This paper develops a theory of the subjectivity of the leader through the philosophical lens of Hegel’s master/slave dialectic and its recent interpretation by the philosopher Judith Butler. This is used to analyse the working life history of a man who rose from poverty to a leadership position in a large company and eventually to running his own successful business. Hegel’s dialectic is foundational to much Western thought, but in this paper, I rashly update it by inserting a leader in between the master, whose approval the leader needs if s/he is to sustain self-hood, and the follower, who becomes a tool that the leader uses when trying to gain that elusive approval. The analysis follows the structure of Butler’s reading of the Dialectic and develops understanding of the norms that govern how leaders should act and the persons they should be. Hard work has become for leaders an ethical endeavour, but they grieve the sacrifice of leisure. They enjoy a frisson of erotic pleasure at their power over others but feel guilt as a result. They must prove their leadership skills by ensuring their followers are perfect employees but at the same time must prove their followers are poor workers who need their continued leadership. This leads to the conclusion that the leader is someone who is both powerful and powerless. This analysis is intended not to demonize leaders, but to show the harm that follows the emphasis on leadership as a desirable and necessary organizational function.

Ce travail traite de l'évitement d'obstacles pour les robots mobiles à roues. D’abord, deux solutions sont proposées dans le cas d’un seul robot autonome. La première est une amélioration de la technique des champs de potentiel afin de contraster l’apparition de minima locaux. Le résultat se base sur l’application de la définition de l’ «Input-to-State Stability» pour des ensembles décomposables. Chaque fois que le robot mobile approche un minimum local l’introduction d’un contrôle dédié lui permet de l’éviter et de terminer la tâche. La deuxième solution se base sur l’utilisation de la technique du «Supervisory Control» qui permet de diviser la tâche principale en deux sous tâches : un algorithme de supervision gère deux signaux de commande, le premier en charge de faire atteindre la destination, le deuxième d’éviter les obstacles. Les deux signaux de commande permettent de compléter la mission en temps fini en assurant la robustesse par rapport aux perturbations représentant certaines dynamiques négligées. Les deux solutions ont été mises en service sur un robot mobile «Turtlebot 2». Pour contrôler une formation de type leader-follower qui puisse éviter collisions et obstacles, une modification de l’algorithme de supervision précédent a été proposée ; elle divise la tâche principale en trois sous-problèmes gérés par trois lois de commande. Le rôle du leader est adapté pour être la référence du groupe avec un rôle actif : ralentir la formation en cas de manœuvre d'évitement pour certains robots. La méthode proposée permet au groupe de se déplacer et à chaque agent d’éviter les obstacles, ou les collisions, de manière décentralisée / This dissertation work addresses the obstacle avoidance for wheeled mobile robots. The supervisory control framework coupled with the output regulation technique allowed to solve the obstacle avoidance problem and to formally prove the existence of an effective solution: two outputs for two objectives, reaching the goal and avoiding the obstacles. To have fast, reliable and robust results the designed control laws are finite-time, a particular class very appropriate to the purpose. The novelty of the approach lies in the easiness of the geometric approach to avoid the obstacle and on the formal proof provided under some assumptions. The solution have been thus extended to control a leader follower formation which, sustained from the previous result, uses two outputs but three controls to nail the problem. The Leader role is redesigned to be the reference of the group and not just the most advanced agent, moreover it has a active role slowing down the formation in case of collision avoidance manoeuvre for some robots. The proposed method, formally proven, makes the group move together and allow each agent to avoid obstacles or collision in a decentralized way. In addition, a further contribution of this dissertation, it is represented by a modification of the well known potential field method to avoid one of the common drawback of the method: the appearance of local minima. Control theory tools helps again to propose a solution that can be formally proven: the application of the definition of Input-to-State Stability (ISS) for decomposable sets allows to treat separate obstacles adding a perturbation which is able to move the trajectory away from a critic point

This study problematizes the down play of heroic perspectives in the currently rising critical and post-heroic leadership research. It argues that compromising either the critical or the post-heroic perspectives in favour of the other would constrict or mislead our understanding of the social influence of leadership processes. This study calls for maintaining the theoretical uniqueness of both perspectives in order to enhance new understandings and broader knowledge claims. Therefore, the study adopts a reflexive-ethnographic examination of the leader-follower and group dynamics, in an International Human Rights Based Organization. The overall aim is to develop an understanding of how individuals in an International Organization like Global Peace Organization (GPO) cope with the universal scope of their organization and the diversity in their work environment. This aim is fulfilled through examining self-narratives generated by the participants in their day to day interactions. To facilitate the coherence between the two leadership perspectives in this examination, a dialectical dimension is enhanced by extending the emerging tactics of reflexivity and intertextuality to the various stages of research. The critical perspective then reveals a context-driven approach in the self-narratives where participants use their particular worldviews to interpret dilemmas and conflicts originating in their work. Conflicts between participants and their leaders also reflect power interplays based on crafting a sense of we-ness / us in self-Other encounters. However, an added perspective on interpersonal relations suggests the significance of the single factor where the less secure participants tend to mask their resistance with creative impression-management strategies. This eventually transforms their insecurities into more positive attitudes and behaviours which repositions them as informal leaders in their groups.

Multispecies grazing research was conducted using meat-type goats (Capra hircus L.) and Jersey heifers (Bos taurus L.) to determine the relationships between multiple grazing treatments and pasture utilization. The study was conducted for 60 days on the Western Kentucky University Farm in Bowling Green, KY. Cattle and goats have shown to differ in grazing preferences and to be economically important to the area. Grazing treatments included goats and cattle grazing simultaneously, sequentially, and goats grazing alone. A typical established Kentucky pasture was utilized with no weed management practices employed. Predominant forage species included tall fescue (Festuca arundinacea Schreb.), orchardgrass (Dactylis glomerata L.), Kentucky bluegrass (Poa pratensis L.), and white clover (Trifolium repens L.). Exclosures were utilized as controls. Data included forage quality, composition, availability, height, visual weed cover and live ground cover, and thistle consumption, collected every 15 days. Results indicated a significant difference in sample dry weights between grazing treatments and ungrazed controls in every treatment except when goats followed cattle. At day 60, grazed areas had significantly lower forage heights than the control when goats grazed with and before cattle. Instances where goats followed cattle resulted in significantly higher NDF compared to the control. All treatments containing goats had significantly lower leaf numbers per thistle plant (Carduus nutans L.) than cattle only treatment. Based on this study, sequential and simultaneous grazing of cattle and goats may be an effective nodding thistle control strategy, but future experimentation is needed for determination of forage utilization and quality relationships.