京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20152号 / 理博第4237号 / 新制||理||1609(附属図書館) / 京都大学大学院理学研究科数学・数理解析専攻 / (主査)教授 堤 誉志雄, 教授 上田 哲生, 教授 國府 寛司 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

It has been shown that the classical Rosenzweig-MacArthur predator-prey model is sensitive to the functional form of the predator response. To see if this sensitivity remains in the highly controlled environment of the chemostat, we use a predator-prey model with three trophic levels and a Holling type II predator response function. We first focus on the analysis of the model using an Ivlev functional response. Local and global dynamics are studied, with global stability of the coexistence equilibrium point obtained under certain conditions. Bifurcation analysis reveals the existence of a stable periodic orbit that appears via a super-critical Hopf bifurcation. The uniqueness of this periodic orbit is explored. Finally, we make comparisons between the dynamics of the model with Ivlev response and Monod response, both of which have nearly identical graphs. The same sensitivity to functional form is observed in the chemostat as in the classical model. / Thesis / Master of Science (MSc)

This paper presents a 3-Region footloose-entrepreneur new economic geography model. Two symmetric regions are part of an economically integrated area (the Union), while the third region represents an outside trade partner. We explore how the spatial allocation of industrial production and employment within the Union is affected by changes in two aspects of trade liberalisation: regional integration and globalisation. Our main contribution pertains to the analysis of the local and global dynamics of the specified factor mobility process. We show that significant parameter ranges exist for which asymmetric distribution of economic activities is one of the possible long-run outcomes. This is a remarkable result within the NEG literature. We then analyse the impact of international trade liberalisation on the dynamics of agglomeration conditional on the endowments of skilled and unskilled labour of the outside region. (authors' abstract) / Series: Department of Economics Working Paper Series

Over the last two decades, Australian higher education has undergone dramatic changes in purpose and orientation. Changes in public funding arrangements and concomitant policy statements have contributed to the reconceptualisation of Australian higher education, and internationalisation has become a core goal for Australian universities. In light of these dynamics, this study examined understandings of internationalisation within two Australian universities. The study examined the ways in which internationalisation was understood by university staff working in either a teaching capacity and/or a managerial position. Situated within the broad field of critical sociology, the study drew on critical realism (Bhaskar, 1979, 1989), critical epistemology (Carspecken, 1996) and reflexive sociology (Bourdieu, 1972, 1990) to analyse how the universities and their staff positioned themselves in relation to the goal of internationalisation. Furthermore, the study examined how this goal served to reposition the institution and/or various forms of university work. The insights of critical social theory were used to examine the contested power relations associated with the growing importance attributed to the goal of internationalisation in Australian higher education. The significance of the study resides in its recognition of the ways in which academic and non-academic subcultures within the university contribute to the goal of internationalisation. Whereas previous research viewed divergence of understandings as weakening the commitment given to internationalisation as an institutional goal, this study has shown that such diversity stems from the differential encounters with and experiences of internationalisation. Moreover, in previous research, the pre-determined objectives for internationalisation resulted in the compartmentalisation of this goal, as in economic objectives and academic objectives. In contrast, this study focused on the dynamic and evolving nature of internationalisation in higher education. Consequently, the study's contribution lies in its explanation of the long term benefits to be derived from viewing internationalisation as a dynamic and generative phenomenon, rather than simply as a pre-determined goal. A case study approach was used in this research with two contrasting onshore Australian universities selected as the case sites. One institution had a reputation as an elite, research intensive university. The other was a post-Dawkins university with a strong vocational orientation. At each site, semi-structured interviews were conducted with staff from across the university's hierarchy. Interviewees included the Pro Vice-Chancellor for the Office of Internationalisation, the Chair of the Academic Board, the Director of the Teaching and Learning Support Unit, Faculty Deans, Heads of Departments, as well as departmental staff concerned with first year teaching. Departmental staff were drawn from two disciplinary areas, Australian History and Marketing. Interviews engaged participants in discussion about the processes by which internationalisation was enacted. Furthermore, university documents, such as the Strategic Plan, were analysed in terms of how the given institution constructed the need for internationalisation and the means by which this goal was to be achieved. The study found that internationalisation involves and promotes constant adaptability. The two institutions used whatever resources they had to develop and promote their international aspirations. The international visions of the institutions were influenced by both their historical and intended relationship with the broader higher education world. The elite, research intensive institution viewed internationalisation with becoming a university of international standing. This institution used its bureaucratic and hierarchical nature to advance its objectives for internationalisation. The vocationally oriented university had developed an internationalisation policy with a view to maximising the revenue to be derived from its diverse international activities and to gaining greater prestige within the higher education field. Staff involved with managerial and/or teaching work were found to develop their ideas about internationalisation through a combination of personal and professional experiences. The study confirmed the growing trend for academics to assume managerial roles in addition to their teaching and research. Consequently, accounts of internationalisation were not necessarily confined to a purely managerial or an academic perspective. Furthermore, the accounts of internationalisation differed between and within the two selected disciplines. On the one hand, specific disciplinary attributes could be seen by the academics interviewed as inherently international, even though they may not assist in realising institutional objectives for internationalisation. On the other, academics spoke of the perceived need for the frames of reference used in undergraduate education to be broadened, given the globalised nature of contemporary society and/or the increasing international enrolments. The study concluded that internationalisation is an important means by which the localised priorities of an institution, an academic department, and/or of individuals can engage with forms of global mobility. Moreover, the study argued the need for all staff and students in Australian higher education to see themselves as part of the processes of internationalisation. This latter point raises questions about the personal and professional attributes required of academics when working within internationalised Australian universities.

Complexity underlying life is largely governed by the dynamics of interaction within and between living and nonliving entities. Evolutionary strategy games are extensively used in modelling and understanding complex behaviors in a wide range of fields including theoretical biology, social interactions, economics, politics, defense and security. Strategy games are said to distill the key elements of interactions be- tween real-world entities and organizations - one of the challenges lies in determining the mapping of complex real life situation dynamics to that of a certain game. That leads us to the two major research questions outlined below. In this thesis, we are taking evolutionary games a step further to investigate the interplay between local and global dynamics, where local dynamics are repre- sented by locally pairwise interactions among the population's players governed by the Iterated Prisoner's Dilemma game. To represent the global dynamics, two main modelling ideas are proposed, in the first model; a mixed evolutionary game is in- troduced where players are competing globally on the population level in a minority game. The interplay between local and global dynamics in this model represents the interplay between different scopes of competition between the same players. Sec- ondly, we introduce a model for studying the effect of sharing global information concerning a population of players, shedding light on how global information can alter the emerging dynamics of local interactions. Furthermore, the thesis addresses the question of whether games - with different dynamics - have unique signatures (footprints) that can be used in recognizing and differentiating among them, and whether these footprints are consistent along the evolutionary path of these games. We show here that by building winning networks between players, and determining network motifs of these winning networks, we can obtain motifs' counts signals that are sufficient to categorize and recognize the game's utility matrix used by the players. We also demonstrate that these footprints - motifs' counts - are consistent along the evolutionary path of the games, due to a hyper-cyclic behavior that exists between strategies. Finally, we show that this approach is capable of identifying whether a certain population is driven by local dynamics or both local and global dynamics using the proposed mixed game.