The Glory of the Past and Geometrical Concurrency

This paper contributes to the general understanding of the geometrical model of concurrency that was named higher dimensional automata (HDAs) by Pratt. In particular we investigate modal logics for such models and their expressive power in terms of the bisimulation that can be captured. The geometric model of concurrency is interesting from two main reasons: its generality and expressiveness, and the natural way in which autoconcurrency and action refinement are captured. Logics for this model, though, are not well investigated, where a simple, yet adequate, modal logic over HDAs was only recently introduced. As this modal logic, with two existential modalities, during and after, captures only split bisimulation, which is rather low in the spectrum of van Glabbeek and Vaandrager, the immediate question was what small extension of this logic could capture the more fine-grained hereditary history preserving bisimulation (hh)? In response, the work in this paper provides several insights. One is the fact that the geometrical aspect of HDAs makes it possible to use for capturing the hh-bisimulation, a standard modal logic that does not employ event variables, opposed to the two logics (over less expressive models) that we compare with. The logic that we investigate here uses standard past modalities and extends the previously introduced logic (called HDML) that had only forward, action-labelled, modalities. Besides, we try to understand better the above issues by introducing a related model that we call ST-configuration structures, which extend the configuration structures of van Glabbeek and Plotkin. We relate this model to HDAs, and redefine and prove the earlier results in the light of this new model. These offer a different view on why the past modalities and geometrical concurrency capture the hereditary history preserving bisimulation. Additional correlating insights are also gained.Comment: 17 pages, 7 figure

Sculptures in Concurrency

We give a formalization of Pratt's intuitive sculpting process for higher-dimensional automata (HDA). Intuitively, an HDA is a sculpture if it can be embedded in (i.e., sculpted from) a single higher dimensional cell (hypercube). A first important result of this paper is that not all HDA can be sculpted, exemplified through several natural acyclic HDA, one being the famous "broken box" example of van Glabbeek. Moreover, we show that even the natural operation of unfolding is completely unrelated to sculpting, e.g., there are sculptures whose unfoldings cannot be sculpted. We investigate the expressiveness of sculptures, as a proper subclass of HDA, by showing them to be equivalent to regular ST-structures (an event-based counterpart of HDA) and to (regular) Chu spaces over 3 (in their concurrent interpretation given by Pratt). We believe that our results shed new light on the intuitions behind sculpting as a method of modeling concurrent behavior, showing the precise reaches of its expressiveness. Besides expressiveness, we also develop an algorithm to decide whether an HDA can be sculpted. More importantly, we show that sculptures are equivalent to Euclidean cubical complexes (being the geometrical counterpart of our combinatorial definition), which include the popular PV models used for deadlock detection. This exposes a close connection between geometric and combinatorial models for concurrency which may be of use for both areas

Elektron Elohim: a cosmic oratorio for soloists, chamber choir, electric guitars and keyboard synthesisers

The doctoral composition concerned by this document is a contemporary oratorio of 95 minutes: it involves seven solo singers (two sopranos, a mezzo, two altos, a tenor and a bass), a polyphonic chamber choir (divided in three to sixteen parts) and an electroacoustic quartet of guitars and synthesisers. The title refers to the otherworldly guardians of the Jewish canon (Tanakh) and speculates on the energetic appearance of the Elohim, reflected by the timbral qualities of the electronic instruments. The narrative, built around four angelic characters (Seraphim) and a female earthling counterpart, outlines in seven movements a fictional cosmogony, and the evolution of human society overseen by astral mentors. The libretto has been written on purpose by the composer himself, mostly in Italian: some multi-linguistic fabrics blend poetry with Christian fragments in Greek and Latin

Involute Analysis: Virtual Discourse, Memory Systems and Archive in the Involutes of Thomas De Quincey

Thomas De Quincey’s involutes inform metaphysical thought on memory and language, particularly concerning multiplicity and the virtual, repetition and difference. When co-opting the mathematic and mechanic involute in Suspiria de Profundis, De Quincey generates an interdisciplinary matrix for the semiotics underpinning his philosophy of language and theory of memory and experience. Involutes entangle and reproduce. De Quincey’s involute exposes the concrete and actual through which all experience accesses the abstract or virtual. The materiality of their informatics and technics provides a literary model and theoretical precursor to a combination of archive and systems theory. The textuality of involute system(s)—both De Quincey\u27s mind and narrative—accommodates the intersections: archive recognizes proliferating layers of re-inscription or a system of discursivity and systems observes the self-regulation of processes and signals/messages in communication. De Quincey\u27s involutes, as a method, transform memory and experience into involute texts: texts invested in the form and layered reading processes of fragmenting and sedimenting data within the strata of memory storage, actively sorted, re-fragmented, reiterated

The impact of the quota-based system on social stratification among the students at the Indian Institute of Technology, Madras, India

This study attempted to identify the impact of the recent expansion in the quota system among Quota-Based Students (QBS) and General Category Students (GCS) at the Indian Institute of Technology (Madras) (IIT(M)). The study emphasized various institutional behaviors that affected the students and their educational endeavors and examined the impact of institutional practices on the students. This study examined some of the socialization practices of QBS and GCS based on Van Maanen and Schein’s (1979) work and revealed that hostels (residence halls) played a significant role especially among QBS educational endeavors at IIT(M). Van Maanen and Schein’s (1979) investiture socialization perspective was extensively evident among various student groups that were allowed by the institution to continue with their previous espoused values within the institution. Right from the admission criteria which is based on caste, numerous signs of social stratification reinforced the class hierarchy along with the existence of various aspects of deficit thinking among QBS at IIT(M). Existence of social stratification within the institution also portrayed traces of stigma consciousness among QBS at the IIT(M). Based on the findings of this research, the co-existence of QBS and GCS along with the emergence of social and academic streams was clearly evident at IIT(M). These two streams shared various similarities with Tinto’s (1988) formal and informal dimensions model. How these groups of students managed to survive in harmony without divesting their Schein’s artifacts, espoused values and underlying assumptions is one of the major outcomes of this study. The results of this study have recommended various strategies to develop programs that will improve the institutional experience and help gain better educational equity among QBS and GCS at IIT(M), India

The modernization of an Iranian city : the case study of Kermanshah

The notion of the Islamic city evoked in comparison with European cities and their modernization process and often criticized for its Eurocentric nature, acknowledges the characteristics’ existence that are shared by traditional cities across the extensive geography, where Islam is the predominant religion. It is not unusual, therefore, to attribute these peculiarities to the shared religious framework, although said framework officially didn’t experience serious modification until twenty centuries, despite the modernization of these cities. Consequently, this study suggests an indirect approach through the study of the modernization process of cities in the Islamic world. The emphasis, thus, no longer rests on specific religious qualities and falls instead on the urban practices and the cultural frameworks in which they are inscribed, resulting from the crystallization of practices and from environmental, social and cultural equilibria in the long-term. Before 1920, Iranian cities were characterized by a set of features which were common in other traditional Islamic cities in the world. As those traditional Islamic cities have been much more studied than the twentieth century changes that have transformed them, we need more holistic and integrated understanding about the changes derived from the modernization process. To explore the broad and wide-spread of their metamorphosis, it is more enlightening if we study second order cities, rather than studying the transformations of major capitals such as Cairo, Istanbul or Tehran, where interventions are more exceptional and more rhetorical. Therefore, this research examines the Kermanshah city, to understand the link between urban and social transformations due to the modernization process. Tracing city, historically, from its traditional form, as prototypical of the so-called Islamic city, to the Pahlavi dynasty (1925-1979) and after the Islamic revolution in 1979. We will focus, particularly, on studying the stages of urban transformation and changes of urban morphology as well as conflicts and differences between traditional urban features with the modern ones. In other words, we are interested in understanding how traditional morphology and structure of the city, like residential and commercial zone, are affected by symbols of development ambition in the each era, like the opening of new and wide boulevards, intensification of land use, disciplining space, embellishing the city and etc. Moreover, we want to trace how these changes influence social structure over the time.La noción de ciudad islámica evocada en comparación con las ciudades europeas y su proceso de modernización y, a menudo, criticada por su naturaleza eurocéntrica, reconoce la existencia de características que comparten las ciudades tradicionales a lo largo de la extensa geografía, donde el Islam es la religión predominante. No es inusual, por lo tanto, atribuir estas peculiaridades al marco religioso compartido, aunque dicho marco oficialmente no experimentó modificaciones serias hasta veinte siglos, a pesar de la modernización de estas ciudades. En consecuencia, este estudio sugiere un enfoque indirecto a través del estudio del proceso de modernización de las ciudades en el mundo islámico. El énfasis, por lo tanto, ya no se basa en cualidades religiosas específicas y cae en cambio en las prácticas urbanas y los marcos culturales en los que están inscritos, como resultado de la cristalización de las prácticas y de los equilibrios ambientales, sociales y culturales en el largo plazo. Antes de 1920, las ciudades iraníes se caracterizaban por un conjunto de características que eran comunes en otras ciudades islámicas tradicionales del mundo. Como esas ciudades islámicas tradicionales han sido mucho más estudiadas que los cambios del siglo XX que las han transformado, necesitamos una comprensión más integral e integrada de los cambios derivados del proceso de modernización. Para explorar la amplia y amplia difusión de su metamorfosis, es más esclarecedor si estudiamos ciudades de segundo orden, en lugar de estudiar las transformaciones de grandes capitales como El Cairo, Estambul o Teherán, donde las intervenciones son más excepcionales y más retóricas. Por lo tanto, esta investigación examina la ciudad de Kermanshah, para entender el vínculo entre las transformaciones urbanas y sociales debido al proceso de modernización. Trazando la ciudad, históricamente, desde su forma tradicional, como prototipo de la llamada ciudad islámica, hasta la dinastía Pahlavi (1925-1979) y después de la revolución islámica en 1979. Nos enfocaremos, particularmente, en estudiar las etapas de la transformación urbana y los cambios de la morfología urbana, así como los conflictos y diferencias entre las características urbanas tradicionales y las modernas. En otras palabras, nos interesa comprender cómo la morfología y la estructura tradicionales de la ciudad, como la zona residencial y comercial, se ven afectadas por símbolos de ambición de desarrollo en cada época, como la apertura de nuevos y amplios bulevares, la intensificación del uso de la tierra, disciplinar el espacio, embellecer la ciudad, etc. Además, queremos rastrear cómo estos cambios influyen en la estructura social a lo largo del tiempo