Numerical tools for the theoretical study of QCD at small x

In this contribution we present the status of two numerical tools designed to study the small x limit of QCD. The first one is a Monte Carlo simulation of the BFKL evolution equation. In design of this approach emphasis has been placed on exploiting the linear behaviour that many variants of the BFKL evolution possess. This allows us to design a procedure which can be used to study theoretical and phenomenological aspects of different kernels. The second one is a semi-analytic approach to study Lipatov's effective action which describes Reggeon interactions. The study of the properties of this action is very complicated and we propose using a computational tool to handle the large amount of non--local vertices and the derivation of higher order corrections.Comment: 7 pages, 3 figures. International Workshop on Diffraction in High-Energy Physics -DIFFRACTION 2006 - September 5-10 2006 Adamantas, Milos island, Greec

Ultra-high molecular sink vacuum chamber

Double-wall vacuum chamber can be separated from the remainder of the system and pumped by ultra-clean techniques. Ultrahigh vacuum is maintained by the cryogenic effect of a cold wall and titanium chemisorption

Wind turbine acoustic standards

A program is being conducted to develop noise standards for wind turbines which minimize annoyance and which can be used to design specifications. The approach consists of presenting wind turbine noise stimuli to test subjects in a laboratory listening chamber. The responses of the subjects are recorded for a range of stimuli which encompass the designs, operating conditions, and ambient noise levels of current and future installations. Results to date have established the threshold of detectability for a range of impulsive stimuli of the type associated with blade/tower wake interactions. The status of the ongoing psychoacoustic tests, the subjective data, and the approach to the development of acoustic criteria/standards are described

Atmospheric analysis modeling in support of Seasat

Atmospheric objective analysis models were developed and tested in preparation for assessing the utility of Seasat data. Of the several discretionary procedures in such computer programs, the effects of three were examined and documented: (1) the effect of varying the weights in the pattern conserving techniques; (2) the effect of varying the data influence region; (3) the effect of including wind information in analysis of mass-structure variables. The problem of inserting bogus reports is also examined

Diffusion algorithms and data reduction routine for onsite launch predictions for the transport of Titan 3 C exhaust effluents

The NASA/MSFC multilayer diffusion algorithms have been specialized for the prediction of the surface impact for the dispersive transport of the exhaust effluents from the launch of a Titan 3 vehicle. This specialization permits these transport predictions to be made at the launch range in real time so that the effluent monitoring teams can optimize their monitoring grids. Basically, the data reduction routine requires just the meteorology profiles for the thermodynamics and kinematics of the atmosphere as an input. These profiles are graphed along with the resulting exhaust cloud rise history, the center line concentrations and dosages, and the hydrogen chloride isopleths

Restrictiveness and guidance in support systems

Restrictiveness and guidance have been proposed as methods for improving the performance of users of support systems. In many companies computerized support systems are used in demand forecasting enabling interventions based on management judgment to be applied to statistical forecasts. However, the resulting forecasts are often ‘sub-optimal’ because many judgmental adjustments are made when they are not required. An experiment was used to investigate whether restrictiveness or guidance in a support system leads to more effective use of judgment. Users received statistical forecasts of the demand for products that were subject to promotions. In the restrictiveness mode small judgmental adjustments to these forecasts were prohibited (research indicates that these waste effort and may damage accuracy). In the guidance mode users were advised to make adjustments in promotion periods, but not to adjust in non-promotion periods. A control group of users were not subject to restrictions and received no guidance. The results showed that neither restrictiveness nor guidance led to improvements in accuracy. While restrictiveness reduced unnecessary adjustments, it deterred desirable adjustments and also encouraged over-large adjustments so that accuracy was damaged. Guidance encouraged more desirable system use, but was often ignored. Surprisingly, users indicated it was less acceptable than restrictiveness