Studies on integrating kinematic design method with mechanical systems simulation techniques

Theultimate goal of any research in the mechanism/kinematic/design area may be called predictive design, ie the optimisation of mechanism proportions in the design stage without requiring extensive life and wear testing. This is an ambitious goal and can be realised through development and refinement of numerical (computational) technology in order to facilitate the design analysis and optimisation of complex mechanisms, mechanical components and systems. As a part of the systematic design methodology this thesis concentrates on kinematic synthesis (kinematic design and analysis) methods in the mechanism synthesis process. The main task of kinematic design is to find all possible solutions in the form of structural parameters to accomplish the desired requirements of motion. Main formulations of kinematic design can be broadly divided to exact synthesis and approximate synthesis formulations. The exact synthesis formulation is based in solving n linear or nonlinear equations in n variables and the solutions for the problem areget by adopting closed form classical or modern algebraic solution methods or using numerical solution methods based on the polynomial continuation or homotopy. The approximate synthesis formulations is based on minimising the approximation error by direct optimisation The main drawbacks of exact synthesis formulationare: (ia) limitations of number of design specifications and (iia) failure in handling design constraints- especially inequality constraints. The main drawbacks of approximate synthesis formulations are: (ib) it is difficult to choose a proper initial linkage and (iib) it is hard to find more than one solution. Recentformulations in solving the approximate synthesis problem adopts polynomial continuation providing several solutions, but it can not handle inequality const-raints. Based on the practical design needs the mixed exact-approximate position synthesis with two exact and an unlimited number of approximate positions has also been developed. The solutions space is presented as a ground pivot map but thepole between the exact positions cannot be selected as a ground pivot. In this thesis the exact synthesis problem of planar mechanism is solved by generating all possible solutions for the optimisation process ¿ including solutions in positive dimensional solution sets - within inequality constraints of structural parameters. Through the literature research it is first shown that the algebraic and numerical solution methods ¿ used in the research area of computational kinematics ¿ are capable of solving non-parametric algebraic systems of n equations inn variables and cannot handle the singularities associated with positive-dimensional solution sets. In this thesis the problem of positive-dimensional solutionsets is solved adopting the main principles from mathematical research area of algebraic geometry in solving parametric ( in the mathematical sense that all parameter values are considered ¿ including the degenerate cases ¿ for which the system is solvable ) algebraic systems of n equations and at least n+1 variables.Adopting the developed solution method in solving the dyadic equations in direct polynomial form in two- to three-precision-points it has been algebraically proved and numerically demonstrated that the map of the ground pivots is ambiguousand that the singularities associated with positive-dimensional solution sets can be solved. The positive-dimensional solution sets associated with the poles might contain physically meaningful solutions in the form of optimal defectfree mechanisms. Traditionally the mechanism optimisation of hydraulically driven boommechanisms is done at early state of the design process. This will result in optimal component design rather than optimal system level design. Modern mechanismoptimisation at system level demands integration of kinematic design methods with mechanical system simulation techniques. In this thesis a new kinematic design method for hydraulically driven boom mechanism is developed and integrated in mechanical system simulation techniques. The developed kinematic design method is based on the combinations of two-precision-point formulation and on optimisation ( with mathematical programming techniques or adopting optimisation methods based on probability and statistics ) of substructures using calculated criteria from the system level response of multidegree-of-freedom mechanisms. Eg. by adopting the mixed exact-approximate position synthesis in direct optimisation (using mathematical programming techniques) with two exact positions and an unlimitednumber of approximate positions the drawbacks of (ia)-(iib) has been cancelled.The design principles of the developed method are based on the design-tree -approach of the mechanical systems and the design method ¿ in principle ¿ is capable of capturing the interrelationship between kinematic and dynamic synthesis simultaneously when the developed kinematic design method is integrated with the mechanical system simulation techniques.

Freedom sounds : vapaus, politiikka ja jazz

Kirjallisuusarvostelu

UAV:n käyttö operaation Iraqi Freedom aikana John Wardenin kehäteorian näkökulmasta

UAV:t (Unmanned Aerial Vehicle, miehittämätön ilma-alus) ovat maasta ohjattavia tiedustelu-, valvonta- ja pommikoneita. Vuonna 2003 alkanut operaatio Iraqi Freedom toimi erinomaisena testikenttänä Yhdysvaltojen miehittämättömille ilma-aluksille. Tutkielman näkökulma rakentuu yhdysvaltalaisen ilmasodankäynnin teoreetikon John Wardenin kehäteorian ympärille, jonka avulla pyritään havainnoimaan UAV:iden suorittamia lentotehtäviä operaation aikana. Tämä tutkielma on laadullinen eli kvalitatiivinen tutkimus. Tutkimusmenetelmänä käytetään tapaustutkimusta. Sen avulla pyritään löytämään selityksiä tutkittavalle ilmiölle arkistolähteistä sekä muusta kirjallisuudesta. John Wardenin kehäteoria koostuu viidestä sisäkkäin olevasta kehästä, jotka rakentuvat eriarvoisista kohteista. UAV:t suorittivat operaation aikana tiedustelu- ja pommituslentoja jokaisella kehällä. Pääpaino oli sisimmällä kehällä, jossa UAV:illa tiedusteltiin Irakin johtamisjärjestelmän kohteita sekä suoritettiin pommituksia tutkakeskuksiin. Omia joukkoja tuettiin UAV:iden avulla siten, että ne tiedustelivat kulkureittejä sekä paikansivat vihollisen tykistö- ja ilmatorjuntakeskittymiä. Havainnot kohteista lähetettiin miehitetyille pommikoneille, jotka suorittivat sitten vaaditut ilmaiskut. Miehittämättömät ilma-alukset kykenivät toimimaan operaation aikana kaikilla teoriamallin kehillä vihollisen ilmatorjunnasta huolimatta. UAV:iden tiedustelutietojen avulla iskettiin täsmällisesti Irakin avainkohteita vastaan. Iskut johtivat lopulta vihollisorganisaation toiminnan lamaantumiseen. UAV on erittäin tehokas ja käytännöllinen ilma-ase, jota tullaan käyttämään enenevässä määrin tulevaisuuden ilmasodankäynnissä.

„Und frei erklär' ich alle meine Knechte“ : Höflichkeit als Ausdruck sozialer Utopie in Schillers Drama Wilhelm Tell.

My dissertation is an interdisciplinary study of the relationship between the Swiss peasants and nobles in Friedrich Schiller’s play Wilhelm Tell (1804). Changes to this relationship are of particular interest. Communication in the play is examined via a micro-analysis based on Penelope Brown’s and Stephen C. Levinson’s theoretical framework Politeness: Some universals in language usage. (1978, 1987). Brown and Levinson distinguish between positivepoliteness and negative-politeness strategies and their distinction is useful for my argument, since they claim that the use of positive-politeness strategies reflects the speaker’s intention to minimize the distance between the interlocutors (Brown and Levinson 1987: 103). Negative-politeness strategies, by contrast, result in social distancing (Brown and Levinson 1987: 130). In accordance with Brown’s and Levinson’s theory, it can be argued that the distribution of positive-politeness and negative-politeness strategies reflects changes in the distance between the fictional interlocutors as representatives of their social classes in Wilhelm Tell. The analysis of the communication in the play highlights that existing conflicts within the social groups are resolved and replaced with solidarity (cf. ‘Claim ’common ground’ and ‘Claim in-group membership with H’) before the peasants and noblemen appear on stage simultaneously in III, 3. In the scene in question, Geßler forces Tell to shoot the apple off his son’s head. Although both nobles and peasants are present, they do not communicate with each other. Thus, communication between the social classes occurs for the first time in IV, 2. This scene is crucial with regard to the changes in the relationship between the social classes in the play. The younger generation, with Rudenz as a representative of the nobility and Melchthal as a representative of the peasants, break with the prevailing conventions and initiate a new type of cooperation based on mutual helping and equality in the right and the duty to protect the country from the violent oppressors representing Habsburg (cf. ‘Convey that S and H are cooperators’, ‘Claim reflexivity’ and ‘Claim reciprocity’). The linguistic analysis reveals the crucial role of the Swiss nobility in the development of the social utopia, as well as the non-contribution of Wilhelm Tell. In fact, Tell never communicates with the Swiss noblemen. The role of the nobility and the role of Wilhelm Tell are further investigated in a comparison between Schiller’s Wilhelm Tell and four of Schiller’s historical sources. These sources, which contain earlier, non-dramatic versions of the establishment of the Swiss Confederation, are the following: Kronica von der loblichen Eydtgnoschaft compiled by Petermann Etterlin (1507), Gemeiner loblicher Eydgnoschafft Stetten Landen vnd Völckeren Chronik wirdiger thaaten beschreybung (1548) written by Johann Stumpf, Chronicon Helveticum of Aegidius Tschudi (the publication of Iselin from 1734 and 1736) and Johannes von Müller’s Geschichten schweizerischer Eidgenossenschaft (1786). Thecomparison sheds light on the fact that both Tschudi and von Müller emphasize unity among the Swiss and cooperation in their attempt to defeat the enemy. However, Schiller has reinforced the role of the nobility in the cooperation. In addition, the comparison between Schiller’s play and the historical sources reveals profound differences with regard to the role of Wilhelm Tell. In all of Schiller’s sources, Tell is present at Rütli, whereas he is absent from Rütli in Schiller’s play. In the play in general, Tell is conspicuously separated from the other peasants. Explanations of my linguistic results, which correspond to the above mentioned differences between the roles of the figures in Wilhelm Tell and the depictions in Schiller’s sources, are found by comparing the path of Schiller’s Swiss towards an egalitarian perspective with the kind of social evolution depicted by the German philosopher Johann Benjamin Erhard in his essay Über das Recht des Volks zu einer Revolution (1795). Aiming at considering Schiller’s social utopia within the larger cultural framework of the German response to the French Revolution, the comparison suggests that both authors depict the need for social change in terms of a change in social hierarchies (Erhard 1970: 95-96, cf. Foi 2005: 225). Erhard’s essay thus helps explain the political intention of Schiller’s play to keep the ideals of the French Revolution as crucial aims but profoundly change the means towards freedom and equality. In his attempt to claim the political resistance of the nobles and peasants as just, however, Schiller sacrificed the figure of Wilhelm Tell. Guilty of the murder of Geßler, Tell was no longer suitable for the righteous revolution imagined by Schiller (cf. Bloch 2008: 215 and Schulz 2005: 228). This explains Tell’s absence in the Rütli scene, his isolation in the plot, as well as his non-contribution to the social utopia. Together, the linguistic analysis and contextualisation of Schiller’s play support my hypothesis that Wilhelm Tell describes a process of change in the relationship between peasants and nobles. The interdisciplinary approach to the topic proved to be fruitful for all areas of the research involved.

Dual light barrier method for six degrees of freedom tool center point calibration of an industrial robot

Tool center point calibration is a known problem in industrial robotics. The major focus of academic research is to enhance the accuracy and repeatability of next generation robots. However, operators of currently available robots are working within the limits of the robot´s repeatability and require calibration methods suitable for these basic applications. This study was conducted in association with Stresstech Oy, which provides solutions for manufacturing quality control. Their sensor, based on the Barkhausen noise effect, requires accurate positioning. The accuracy requirement admits a tool center point calibration problem if measurements are executed with an industrial robot. Multiple possibilities are available in the market for automatic tool center point calibration. Manufacturers provide customized calibrators to most robot types and tools. With the handmade sensors and multiple robot types that Stresstech uses, this would require great deal of labor. This thesis introduces a calibration method that is suitable for all robots which have two digital input ports free. It functions with the traditional method of using a light barrier to detect the tool in the robot coordinate system. However, this method utilizes two parallel light barriers to simultaneously measure and detect the center axis of the tool. Rotations about two axes are defined with the center axis. The last rotation about the Z-axis is calculated for tools that have different width of X- and Y-axes. The results indicate that this method is suitable for calibrating the geometric tool center point of a Barkhausen noise sensor. In the repeatability tests, a standard deviation inside robot repeatability was acquired. The Barkhausen noise signal was also evaluated after recalibration and the results indicate correct calibration. However, future studies should be conducted using a more accurate manipulator, since the method employs the robot itself as a measuring device.

The collective dimension of freedom of religion or belief in international law : the application of findings to the case of Turkey

Pertinent domestic and international developments involving issues related to tensions affecting religious or belief communities have been increasingly occupying the international law agenda. Those who generate and, thus, shape international law jurisprudence are in the process of seeking some of the answers to these questions. Thus the need for reconceptualization of the right to freedom of religion or belief continues as demands to the right to freedom of religion or belief challenge the boundaries of religious freedom in national and international law. This thesis aims to contribute to the process of “re-conceptualization” by exploring the notion of the collective dimension of freedom of religion or belief with a view to advance the protection of the right to freedom of religion or belief. The case of Turkey provides a useful test case where both the domestic legislation can be assessed against international standards, while at the same time lessons can be drawn for the improvement of the standard of international review of the protection of the collective dimension of freedom of religion or belief. The right to freedom of religion or belief, as enshrined in international human rights documents, is unique in its formulation in that it provides protection for the enjoyment of the rights “in community with others”.1 It cannot be realized in isolation; it crosses categories of human rights with aspects that are individual, aspects that can be effectively realized only in an organized community of individuals and aspects that belong to the field of economic, social and cultural rights such as those related to religious or moral education. This study centers on two primary questions; first, what is the scope and nature of protection afforded to the collective dimension of freedom of religion or belief in international law, and, secondly, how does the protection of the collective dimension of freedom of religion or belief in Turkey compare and contrast to international standards? Section I explores and examines the notion of the collective dimension of freedom of religion or belief, and the scope of its protection in international law with particular reference to the right to acquire legal personality and autonomy religious/belief communities. In Section II, the case study on Turkey constitutes the applied part of the thesis; here, the protection of the collective dimension is assessed with a view to evaluate the compliance of Turkish legislation and practice with international norms as well as seeking to identify how the standard of international review of the collective dimension of freedom of religion or belief can be improved.

Designing new learning experiences? : exploring corporate E-learners’ self-regulated learning

The context of this study is corporate e-learning, with an explicit focus on how digital learning design can facilitate self-regulated learning (SRL). The field of e-learning is growing rapidly. An increasing number of corporations use digital technology and elearning for training their work force and customers. E-learning may offer economic benefits, as well as opportunities for interaction and communication that traditional teaching cannot provide. However, the evolving variety of digital learning contexts makes new demands on learners, requiring them to develop strategies to adapt and cope with novel learning tools. This study derives from the need to learn more about learning experiences in digital contexts in order to be able to design these properly for learning. The research question targets how the design of an e-learning course influences participants’ self-regulated learning actions and intentions. SRL involves learners’ ability to exercise agency in their learning. Micro-level SRL processes were targeted by exploring behaviour, cognition, and affect/motivation in relation to the design of the digital context. Two iterations of an e-learning course were tested on two groups of participants (N=17). However, the exploration of SRL extends beyond the educational design research perspective of comparing the effects of the changes to the course designs. The study was conducted in a laboratory with each participant individually. Multiple types of data were collected. However, the results presented in this thesis are based on screen observations (including eye tracking) and video-stimulated recall interviews. These data were integrated in order to achieve a broad perspective on SRL. The most essential change evident in the second course iteration was the addition of feedback during practice and the final test. Without feedback on actions there was an observable difference between those who were instruction-directed and those who were self-directed in manipulating the context and, thus, persisted whenever faced with problems. In the second course iteration, including the feedback, this kind of difference was not found. Feedback provided the tipping point for participants to regulate their learning by identifying their knowledge gaps and to explore the learning context in a targeted manner. Furthermore, the course content was consistently seen from a pragmatic perspective, which influenced the participants’ choice of actions, showing that real life relevance is an important need of corporate learners. This also relates to assessment and the consideration of its purpose in relation to participants’ work situation. The rigidity of the multiple choice questions, focusing on the memorisation of details, influenced the participants to adapt to an approach for surface learning. It also caused frustration in cases where the participants’ epistemic beliefs were incompatible with this kind of assessment style. Triggers of positive and negative emotions could be categorized into four levels: personal factors, instructional design of content, interface design of context, and technical solution. In summary, the key design choices for creating a positive learning experience involve feedback, flexibility, functionality, fun, and freedom. The design of the context impacts regulation of behaviour, cognition, as well as affect and motivation. The learners’ awareness of these areas of regulation in relation to learning in a specific context is their ability for design-based epistemic metareflection. I describe this metareflection as knowing how to manipulate the context behaviourally for maximum learning, being metacognitively aware of one’s learning process, and being aware of how emotions can be regulated to maintain volitional control of the learning situation. Attention needs to be paid to how the design of a digital learning context supports learners’ metareflective development as digital learners. Every digital context has its own affordances and constraints, which influence the possibilities for micro-level SRL processes. Empowering learners in developing their ability for design-based epistemic metareflection is, therefore, essential for building their digital literacy in relation to these affordances and constraints. It was evident that the implementation of e-learning in the workplace is not unproblematic and needs new ways of thinking about learning and how we create learning spaces. Digital contexts bring a new culture of learning that demands attitude change in how we value knowledge, measure it, define who owns it, and who creates it. Based on the results, I argue that digital solutions for corporate learning ought to be built as an integrated system that facilitates socio-cultural connectivism within the corporation. The focus needs to shift from designing static e-learning material to managing networks of social meaning negotiation as part of a holistic corporate learning ecology.