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Neutron stars are invaluable tools for exploring stellar death, the physics of ultra-dense matter, and the effects of extremely strong magnetic fields. The observed population of neutron stars is dominated by the >1000 radio pulsars, but there are distinct sub-populations that, while fewer in number, can have significant impact on our understanding of the issues mentioned above. These populations are the nearby, isolated neutron stars discovered by ROSAT, and the central compact objects in supernova remnants. The studies of both of these populations have been greatly accelerated in recent years through observations with the Chandra X-ray Observatory and the XMM-Newton telescope. First, we discuss radio, optical, and X-ray observations of the nearby neutron stars aimed at determining their relation to the Galactic neutron star population and at unraveling their complex physical processes by determining the basic astronomical parameters that define the population---distances, ages, and magnetic fields---the uncertainties in which limit any attempt to derive basic physical parameters for these objects. We conclude that these sources are 1e6 year-old cooling neutron stars with magnetic fields above 1e13 Gauss. Second, we describe the hollow supernova remnant problem: why many of the supernova remnants in the Galaxy have no indication of central neutron stars. We have undertaken an X-ray census of neutron stars in a volume-limited sample of Galactic supernova remnants, and from it conclude that either many supernovae do not produce neutron stars contrary to expectation, or that neutron stars can have a wide range in cooling behavior that makes many sources disappear from the X-ray sky.

The diversity of stellar death is revealed in the energy, velocity and geometry of the explosion debris ("ejecta''). Using multi-wavelength observations of gamma-ray burst (GRB) afterglows I show that GRBs, arising from the death of massive stars, are marked by relativistic, collimated ejecta ("jets'') with a wide range of opening angles. These results suggest that various cosmic explosions are powered by a common energy source, an "engine'' (possibly an accreting stellar-mass black hole), with their diverse appearances determined solely by the variable high velocity output. On the other hand, using radio observations I show that local type Ibc core-collapse supernovae generally lack relativistic ejecta and are therefore not powered by engines. Instead, the highest velocity debris in these sources, typically with a velocity lower than 100,000 km/sec, are produced in the (effectively) spherical ejection of the stellar envelope. The relative rates of engine- and collapse-powered explosions suggest that the former account for only a small fraction of the stellar death rate. Using the first radio and submillimeter observations of GRB hosts, I show that some are extreme starburst galaxies with the bursts directly associated with the regions of most intense star formation. I suggest, by comparison to other well-studied samples, that GRBs preferentially occur in sub-luminous, low mass galaxies, undergoing the early stages of a starburst process. If confirmed with future observations, this trend will place GRBs in the forefront of star formation and galaxy evolution studies.

Does God change? Does it matter? If God is the immutable God, as interpreted from Classical Christian Tradition, a God who remains unalterable, what is the point of prayer? Does prayer, or any of our actions in the world for that matter, have any effect on God? Can we move God? Is God simply a static Being? Is prayer of use if God is absolutely immutable? Does God respond to prayer or to our actions in the world? Classical Tradition has presented us with a picture of an immutable God, a mono-polar God, who remains unalterable, unchanged, transcendent to our history in the world. Yet scriptural revelation and personal religious experience presents us with a God who, whilst transcendent to the world is also immanent, the God of Love who creates, redeems, a God who is affected by, who responds to, what is happening in the world; a God who listens and relates. William Norris Clarke's neo-Thomistic consideration of the nature of God's immutability rests on the basis of the notion of the Dynamic Being of God and forms the final focus and basis for our seeking a reconciliation of tradition, scripture and personal religious experience with respect to the nature of God's immutability. Discussion of Norris Clarke's work is supplemented by a consideration of the work of Robert A. Connor, and in support, that of David Schindler. Norris Clarke's classical reinterpretation gives credence both to scriptural revelation and personal experience of God's historical relationality and responsiveness to humankind without betraying the Classical Tradition. With independent support by Connor and in dialogue with Schindler, it becomes the favoured viewpoint.

In an effort to extend traditional human-computer interfaces research has introduced embodied agents to utilize the modalities of everyday human-human communication, like facial expression, gestures and body postures. However, giving computer agents a human-like body introduces new challenges. Since human users are very sensitive and critical concerning bodily behavior the agents must act naturally and individually in order to be believable. This dissertation focuses on conversational gestures. It shows how to generate conversational gestures for an animated embodied agent based on annotated text input. The central idea is to imitate the gestural behavior of a human individual. Using TV show recordings as empirical data, gestural key parameters are extracted for the generation of natural and individual gestures. The gesture generation task is solved in three stages: observation, modeling and generation. For each stage, a software module was developed. For observation, the video annotation research tool ANVIL was created. It allows the efficient transcription of gesture, speech and other modalities on multiple layers. ANVIL is application-independent by allowing users to define their own annotation schemes, it provides various import/export facilities and it is extensible via its plug-in interface. Therefore, the tool is suitable for a wide variety of research fields. For this work, selected clips of the TV talk show ``Das Literarische Quartett'' were transcribed and analyzed, arriving at a total of 1,056 gestures. For the modeling stage, the NOVALIS module was created to compute individual gesture profiles from these transcriptions with statistical methods. A gesture profile models the aspects handedness, timing and function of gestures for a single human individual using estimated conditional probabilities. The profiles are based on a shared lexicon of 68 gestures, assembled from the data. Finally, for generation, the NOVA generator was devised to create gestures based on gesture profiles in an overgenerate-and-filter approach. Annotated text input is processed in a graph-based representation in multiple stages where semantic data is added, the location of potential gestures is determined by heuristic rules, and gestures are added and filtered based on a gesture profile. NOVA outputs a linear, player-independent action script in XML.

This book offers not only a comprehensive analysis of the conflicts in Africa but also a milestone suggestion of what could be a breakthrough in attempts at resolving them. It suggests that underdevelopment lies at the genesis of most of the conflicts. The herein enunciated Developmental Peace Theory offers a more tenacious solution to the conflicts than the traditional Democratic Peace Theory. Conflicts would be avoided if Africans could concentrate on developing those aspects that protect them from preventable morbidity and sporadic hunger. This book is an interesting expose of the often neglected development approach to African conflicts. It contrasts the African democratisation process and development, while providing case study analysis to illustrate the real effects the phenomena have had on political transition and nation-building on the ground.

This text marks a little milestone in the understanding of the democratic peace theory in transitional states. It brings in a much needed perspective on the achievements and limitations of democracy in Sub-Saharan Africa, and the role it plays or could play in the search for solutions to conflicts in the sub-region. The author provides a differentiated view of the traditional Western notions of democracy and its role in the search for political stability and nation-building.A series of fragile democratic developments in contemporary politics in the continent have set in processes of change in governance patterns and understandings about the idea of a nation state. However, these processes have been unable to stem the tide of conflicts that continue to raise their bloody heads in the continent. The author takes a critical look at the reasons for this limitation, while probing into the necessity for alternative ways of thinking about the causes and solutions to the conflicts.This text offers students and researchers a quick glance at the sources of conflicts in Sub-Saharan Africa and an assessment of the implications of attempting to use democracy alone as a solution.

Students of organisation have used complexity theory in many different ways and for many different reasons. What characterises the writings of most 'management thinkers', however, is that the authors are primarily concerned with the question of "how to make this complexity thing work for us?" This study takes a rather different approach. Ideas and concepts of the science of complexity are borrowed to develop the idea that organisations live lives of their own - an idea that is very much at odds with the dominant view that understands organisations as tools that we use to realise certain goals. To illustrate matters, the book discusses the developments of the organisation of Vitesse, a mediocre Dutch professional football club that according to its president needed to be transformed into a major player in the family entertainment industry.