A Note on Diogmitae

published or submitted for publicatio

The J-Box Problem

The study group was presented with the problem of determining the behaviour of a web of wet cellulose fibres - called a tow - as it passes through part of the manufacturing process. The name of the problem derives from the fact that on its passage down the production line the tow passes through a J-shaped box, whose purpose is to provide a buffer where the tow is stored long enough and hot enough for certain chemical reactions to take place, mainly concerned with giving the right quality to the fibre surface. (The production line in fact involves two J-boxes, one containing wet tow, the other dry, and we are here entirely concerned with the first of these, the wet J-box.) Three aspects of the tow behaviour were proposed for investigation: 1. What is the mechanical behaviour of the tow within the J-box ? Specifically, how do the time spent within the J-box and the shape of the tow outlet column depend on the J- box geometry, tow density and compressibility, flow rate, friction coefficients etc. 2. What is the temperature history, and hence the chemical history, of the tow within the J-box? 3. Why do dislocations and loops occur within the tow? We first give typical parameters and other details of the process, and then further details of these three questions

Μαρτυρία для Аполлония Тианского

Автор ставит задачу проанализировать одно из т.н. писем Аполлония Тианского. Исследователь доказывает, что письмо это точно соответствует форме официального "свидетельства о заслугах", и делает попытку подтвердить существующее в историографии наблюдение, что автором письма был не император Клавдий, а некий римский гражданин, имя которого было вычеркнуто из текста

A guide to the construction of the DGSM Nottingham Melton Lithoframe 50K Colston Bassett Gocad model

This report describes the rationale behind the construction of the Nottingham Melton Lithoframe 50K GOCAD model for the Colston Bassett area. This work was carried out between April 2001-March 2005, as part of the Nottingham Melton DGSM-UK project (E1362S96 Task 06). This model comprises part of the area covered by the Melton 50K geological map sheet (142)

European Retrofit Network: Retrofitting Evaluation Methodology Report

The research programme, funded by the EU Progress Fund, looks at the potential impacts of construction training in the area of „retrofitting‟ social housing to make it more sustainable, in particular to improve energy efficiency and reduce greenhouse gas emissions. This report investigates methodologies for measuring and demonstrating carbon emissions reductions resulting from retrofitting measures in the partner countries (UK, Spain, Poland and Montenegro). The output of this part of the study is a methodology appropriate to measuring the likely carbon reduction impacts through common retrofit measures in the social housing sector, taking into account the likely cost effectiveness of measures, the impact on occupants, the project management challenges and thus the measures that are most likely to be employed in policy and practice. An appropriate methodology is one that can be applied across the range of different conditions found in the partner countries (representative to some degree of the range of conditions found across Europe as whole). Low carbon retrofit has been defined as „incremental improvements to the building fabric and systems with primary intention of improving energy efficiency and reducing carbon emissions.

A guide to the construction of the DGSM Nottingham Melton Lithoframe 250K model

This report describes the rationale behind the construction of the Nottingham Melton Lithoframe 250K GOCAD model. This work was carried out between April 2001-March 2005, as part of the Nottingham Melton DGSM-UK project (E1362S96 Task 06). This model comprises the area of the combined Nottingham and Melton 50K geological map sheets

The Effective Potential, the Renormalisation Group and Vacuum Stability

We review the calculation of the the effective potential with particular emphasis on cases when the tree potential or the renormalisation-group-improved, radiatively corrected potential exhibits non-convex behaviour. We illustrate this in a simple Yukawa model which exhibits a novel kind of dimensional transmutation. We also review briefly earlier work on the Standard Model. We conclude that, despite some recent claims to the contrary, it can be possible to infer reliably that the tree vacuum does not represent the true ground state of the theory.Comment: 23 pages; 5 figures; v2 includes minor changes in text and additional reference

Fields Annihilation and Particles Creation in DBI inflation

We consider a model of DBI inflation where two stacks of mobile branes are moving ultra relativistically in a warped throat. The stack closer to the tip of the throat is annihilated with the background anti-branes while inflation proceeds by the second stack. The effects of branes annihilation and particles creation during DBI inflation on the curvature perturbations power spectrum and the scalar spectral index are studied. We show that for super-horizon scales, modes which are outside the sound horizon at the time of branes collision, the spectral index has a shift to blue spectrum compared to the standard DBI inflation. For small scales the power spectrum approaches to its background DBI inflation value with the decaying superimposed oscillatory modulations.Comment: First revision: minor changes, the background spectral index is corrected, new references are added. Second revision: minor changes, new references are added, accepted for publication in JCA

Inflation on Fractional Branes: D--Brane Inflation as D--Term Inflation

We describe a D--brane inflation model which consists of two fractional D3 branes separated on a transverse $T^2 \times K3$. Inflation arises due to the resolved orbifold singularity of $K3$ which corresponds to an anomalous D--term on the brane. We show that D--brane inflation in the bulk corresponds to D--term inflation on the brane. The inflaton and the trigger field parametrize the interbrane distances on $T^2$ an $K3$ respectively. After inflation the branes reach a supersymmetric configuration in which they are at the origin of $T^2$ but separated along the $K3$ directions.Comment: 15 pages in phyzzx.tex; minor corrections including all factors of 2\pi; v3: more minor correction

Cosmology and two-body problem of D-branes

In this paper, we investigate the dynamics and the evolution of the scale factor of a probe Dp-brane which move in the background of source Dp-branes. Action of the probe brane is described by the Born-Infeld action and the interaction with the background R-R field. When the probe brane moves away from the source branes, it expands by power law, whose index depends on the dimension of the brane. If the energy density of the gauge field on the brane is subdominant, the expansion is decelerating irrespective of the dimension of the brane. On the other hand, when the probe brane is a Nambu-Goto brane, the energy density of the gauge field can be dominant, in which case accelerating expansion occurs for $p \leq 4$. The accelerating expansion stops when the brane has expanded sufficiently so that the energy density of the gauge field become subdominant.Comment: 6 pages, 7 figures, reference added, accepted for publication in PR