Paper Session III-B - Potential European Involvement in the US Pathfinder Program

In conjunction with a long-range space programme planning also in Europe ideas exist for planetary exploratory missions, such as for Mars and the necessary infrastructure and technologies, required. Of course, this can only be realized in international cooperation as proposed by NASA with the pathfinder initiative. Europe has been engaged in a number of unmanned scientific missions, some of them still have to be flown - such as Galileo, Ulysses, and/or Cassini - and further unmanned explorations of Mars will still have to be done as well as experiences to be gained on longer-duration stays of man in space before a manned exploration of Mars can be realized. Also advances in technologies have to be made such as for energy and life support systems, required for such long-duration space missions. Since Europe already has been engaged in the manned Spacelab programme and a further involvement in the US Space Station programme has been decided - together with European programme in the area of advanced launchers with manned reentry capabilities - it is believed that Europe can also play an adequate role eventually in the pathfinder programme. In the paper alternatives for an efficient transport to the Moon and/or Mars and the return to Earth will be discussed, showing the logistics for certain assumptions with respect to the evolutionary missions. Some efforts will also be devoted to the various technologies, which will have to be gradually developed and demonstrated, before the actual goal of a manned exploration of Mars can take place with a certain degree of efficiency. It surely will be a big challenge for international cooperation in space in the 21st century

Towards an Intelligent Workflow Designer based on the Reuse of Workflow Patterns

In order to perform process-aware information systems we need sophisticated methods and concepts for designing and modeling processes. Recently, research on workflow patterns has emerged in order to increase the reuse of recurring workflow structures. However, current workflow modeling tools do not provide functionalities that enable users to define, query, and reuse workflow patterns properly. In this paper we gather a suite for both process modeling and normalization based on workflow patterns reuse. This suite must be used in the extension of some workflow design tool. The suite comprises components for the design of processes from both legacy systems and process modeling

Navier-Stokes analysis and experimental data comparison of compressible flow within ducts

Many aircraft employ ducts with centerline curvature or changing cross-sectional shape to join the engine with inlet and exhaust components. S-ducts convey air to the engine compressor from the intake and often decelerate the flow to achieve an acceptable Mach number at the engine compressor by increasing the cross-sectional area downstream. Circular-to-rectangular transition ducts are used on aircraft with rectangular exhaust nozzles to connect the engine and nozzle. To achieve maximum engine performance, the ducts should minimize flow total pressure loss and total pressure distortion at the duct exit. Changes in the curvature of the duct centerline or the duct cross-sectional shape give rise to streamline curvature which causes cross stream pressure gradients. Secondary flows can be caused by deflection of the transverse vorticity component of the boundary layer. This vortex tilting results in counter-rotating vortices. Additionally, the adverse streamwise pressure gradient caused by increasing cross-sectional area can lead to flow separation. Vortex pairs have been observed in the exit planes of both duct types. These vortices are due to secondary flows induced by pressure gradients resulting from streamline curvature. Regions of low total pressure are produced when the vortices convect boundary layer fluid into the main flow. The purpose of the present study is to predict the measured flow field in a diffusing S-duct and a circular-to-rectangular transition duct with a full Navier-Stokes computer program, PARC3D, and to compare the numerical predictions with new detailed experimental measurements. The work was undertaken to extend previous studies and to provide additional CFD validation data needed to help model flows with strong secondary flow and boundary layer separation. The S-duct computation extends the study of Smith et al, and Harloff et al, which concluded that the computation might be improved by using a finer grid and more advanced turbulence models. The present study compares results for both the Baldwin-Lomas and k-epsilon turbulence models and is conducted with a refined grid. For the transition duct, two inlet conditions were considered, the first with straight flow and the second with swirling flow. The first case permits examination of the effects of the geometric transition on the flow field, while the second case includes the rotational flow effect characteristic of a gas turbine engine

ІНЖЕНЕРИ У СКЛАДІ ДЕПУТАЦІЇ ВІД УКРАЇНСЬКИХ ГУБЕРНІЙ У ДЕРЖАВНІЙ ДУМІ РОСІЙСЬКОЇ ІМПЕРІЇ (1906-1917 рр.)

В останні два-три десятиліття історики проявляють постійний інтерес до народу як носія влади і до форм участі його в державотворенні. Досвід прожи-тих років трактується як надбання нації, відтак вивчення комплексу проблем, пов’язаних з участю депутатів від українських губерній Російської імперії в ін-ституції парламентського типу – Державній думі – є актуальною проблемою. Об’єктом цього дослідження є суспільно-політичні процеси в українських губе-рніях Російської імперії, власне у Наддніпрянській Україні, на початку ХХ ст., предметом – депутати Державної думи перших чотирьох скликань, обрані від українських губерній і міст, конкретно – інженери за фахом. Мета дослідження – розгляд соціопрофесійної групи технічної інтеліген-ції в загальному складі думської депутації. Цьому складу притаманна в цілому дуже строката структура у своїх соціальних, політичних, освітніх, професійних, конфесійних та інших характеристиках. Тому, окрім іншого, необхідно визна-чити місце інженерів у цьому середовищі й подати конкретну інформацію про них. При цьому власне думська діяльність їх наразі не розглядається, як і пода-льша їх доля після 1917 року. Завдання щодо конкретної інформації випливає зі стану історіографічної розробки проблеми. Думська проблематика є дуже популярною у Російській Федерації; сплеск інтересу до неї посилився у зв'язку з широким відзначенням столітнього ювілею Думи у РФ у 2006 році [13]. В Україні досі не існує якогось центру вивчення зазначених проблем, проте на рівні дисертаційних досліджень та статей їх розробка все ж здійснюється, причому географія таких досліджень досить широка, від Харкова до Кам’янця-Подільського [9; 5]. Висвітлення ж теми у заявленому формулюванні досі нам невідоме

Spring wheat yield assessment under drought conditions using vegetation health index: case of Canadian prairies

Non-Peer ReviewedAgricultural drought is a major climate concern which occurs frequently on Canadian prairies. It acts negatively on crop production, which directly affects the Canadian economy. The Normalized Difference Vegetation Index (NDVI) has been widely used to assess crop yield losses related to drought events. However, this index suffers from some shortcomings such as the apparent time lag between drought impact due to rainfall deficit and NDVI response. This study was undertaken to investigate the effectiveness of the integrated Vegetation Health Index (iVHI) for the assessment of spring wheat yield across Canadian prairies. A time series of five years from the Advanced Very High Resolution Radiometer (AVHRR) sensor were used to develop a spring wheat yield model for three agroclimatic regions: subarid, semiarid and subhumid. The results demonstrated that spring wheat yield assessment is feasible through the use of iVHI, especially in subarid and semiarid regions where it reached a correlation coefficient of 0.75 and 0.61, respectively. This finding shows that iVHI can be used to estimate spring wheat yield losses due to agricultural drought across the Canadian prairies. However, in subhumid regions where spring wheat growing conditions are favourable because of adequate water supply, the integrated NDVI (iNDVI) outperforms iVHI with a correlation coefficient of 0.44 compared to 0.34. Consequently, to develop an efficient tool, it suggested coupling the iVHI with iNDVI to better estimate spring wheat yield in the Canadian prairies

A search for X-ray emission from rich clusters, extended halos around clusters, and superclusters

The all-sky data base acquired with the HEAO A-2 experiment was searched for X-ray emission on a variety of metagalactic size scales which were either predicted or previously detected. Results in the 0.2-60 keV energy range are presented. The optically richest clusters, including those from which a microwave decrement were observed, appear to be relatively underluminous in X-rays. Observations of Abell 576 show its luminosity to be less than earlier estimates, and moreover less than the luminosity predicted from its microwave decrement, unless the intracluster gas is a factor of approximately 10 hotter than in typical clusters. Near SC0627 there are two X-ray sources, and the identification of the dominant source with SCO627 is probably incorrect. New spectral observations of Abell 401 and 2147, possible superclusters, reveal that they have typical cluster spectra with iron line emission

Colloidal hydrodynamic coupling in concentric optical vortices

Optical vortex traps created from helical modes of light can drive fluid-borne colloidal particles in circular trajectories. Concentric circulating rings of particles formed by coaxial optical vortices form a microscopic Couette cell, in which the amount of hydrodynamic drag experienced by the spheres depends on the relative sense of the rings' circulation. Tracking the particles' motions makes possible measurements of the hydrodynamic coupling between the circular particle trains and addresses recently proposed hydrodynamic instabilities for collective colloidal motions on optical vortices.Comment: 7 pages, 2 figures, submitted to Europhysics Letter

Pan-European grading scales: lessons from national systems and the ECTS

This article assesses the impact of the Bologna Process on the grading schemes of EU member countries. In light of some problems regarding the implementation of the European Credit Transfer system (ECTS), the author proposes further reforms and offers some elements of a unified grading system for European higher education. The author explores the variation among Europe’s grading systems and the resulting lessons learned are shared here. Lastly, this article also argues that principles of justice and fairness, deemed central to academic freedom, are best upheld by the use of a unified grading system at national and European levels