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The IVS Intensive sessions are single-baseline, 1-h VLBI sessions carried out everyday in order to determine Universal Time (UT1). We investigate different possibilities to improve the results of such sessions. We do this investigation by extracting 2-h single-baseline sessions from the CONT08 data set. These are analysed like normal Intensives, and the results are compared to the results of the analysis of the full CONT08 data set. We find that tropospheric asymmetry is the major error source for the single-baseline sessions. It is possible to improve the accuracy of the estimated UT1 either by using accurate a priori tropospheric gradients or by estimating gradients in the data analysis. [ABSTRACT FROM AUTHOR]

Abstract: Long-term sedimentary sequences provide a wealth of useful information for research into the palaeo-environment, especially in relation to past climate change. Shorter records provide similar information in many archaeological contexts. However if such records are to be used to provide precise timing of events, and more critically the relative timing between different records, methods are needed to provide accurate and precise age–depth models for these sequences. Given the imprecision of individual calibrated radiocarbon determinations it is necessary to use the information we have about the deposition process to refine our chronologies and also to provide interpolation between dated levels in any sequence. Even with layer counted chronologies, the uncertainties are sometimes hard to quantify. This paper outlines a range of Bayesian models for deposition which have been implemented in the computer programme OxCal. These models can be used to combine information from the sediments themselves with radiocarbon or other direct dating information. Such models have the potential to integrate information between different records and provide a coherent chronology on which to base environmental or archaeological research. [Copyright &y& Elsevier]

Evolution of winding strings in spacetimes with cycles whose proper lengths depend on time is examined. It was established earlier that extended objects wrapping the shrinking dimension in compactified Milne spacetime enjoy classically nonsingular evolution. Extensions of this observation to other spacetimes are discussed. [ABSTRACT FROM AUTHOR]

This paper contrasts two important features of parallel system computations: fairness and timing. The study is carried out at a specification system level by resorting to a well-known process description language. The language is extended with labels which allow to filter out those process executions that are not (weakly) fair [as in Costa and Stirling (Acta Inf. 21:417–441, 1984) and in Costa and Stirling (Inf. Comput. 73:207–244, 1987)], and with upper time bounds for the process activities (as in Corradini et al. Acta Inf. 38:735–792, 2002). We show that fairness and timing are closely related. Two main results are stated. First, we show that each everlasting (or non-Zeno) timed process execution is fair. Second, we provide a characterization for fair executions of untimed processes in terms of timed process executions. This results in a finite representation of fair executions using regular expressions. [ABSTRACT FROM AUTHOR]

Time is a unique dimension of the universe, along with perhaps 10 dimensions of space, according to superstring theory. Our brain and its associated consciousness perceive time as a continuous unidirectional stream. Even though we appear to be able to move freely in three dimensions of space; time's arrow for us points only one way, the present eroding into the future to leave the past behind. For two millennia, time has been likened to a stream or river. In the West, for the past two centuries, time and change have been equated almost automatically with the idea of progress. However, change always brings with it loss as well as gain, and progress is far from inevitable. This remains true in the history of medicine. The history of any subject is full of blind alleys, which, although important at the time, generally become edited out in retrospect. [ABSTRACT FROM AUTHOR]

This essay contests the standard historical comparison that links Husserl's account of time-consciousness to the tradition by way of Book XI of Augustine's Confessions. This comparison rests on the mistaken assumption that both thinkers attribute the soul's distention and corresponding apprehension of time to memory. While true for Augustine and Husserl's 1905 lectures on time, Husserl concluded after 1907 that these lectures advanced the flawed and counter-intuitive position that memory extends perception. I will trace the shortcomings of Augustine's and Husserl's conflation of memory with perception. After developing Husserl's maturely articulated distinction between memory and retention from 1911, I suggest chapters 10-14 of Aristotle's Physics IV as a more apt anticipation of this second, more adequate half of the Husserlian story. A reconstruction of Aristotle's definition of time as "the number of movement," one that privileges the activity of "the mind pronouncing that the 'nows' are two," intimates Husserl's distinction between memory and retention. For Aristotle, the soul's recognition of the 'nows' as two depends not on memory, but on the soul's intentional activity of counting, itself dependent on the ability to, as Aristotle writes in his Metaphysics, "grasp mentally and [have] already grasped" at the same time. [ABSTRACT FROM AUTHOR]

Presents a paper which searches for an explicit expression of the so-called problem of the direction of time. Indication that the traditional version of the problem is an artifact of a mistaken view in the foundations of statistical mechanics; What the problem arises from; Indepth look at the problem of the direction of time.

Explains a motion of time. Implications of several types of clocks for two physical systems; Treatment to now not as a material object; Consistency and intelligibility of the transient theory of time.

Reviews the sound recordings "A Form of Time and a Moment of Kairos," parts 1 and 2, which focused on the suspension of time.

The article discusses questions related to the end of the nineteenth century. A century is defined as hundred things of the kind, for example, 100 years. It takes 100 full years to make a century of time. The nineteenth century has to go right to the last second of the 1900 before it has rounded 100 full years.