1,483 research outputs found
I.P. skvortzov and imperial Kazan university
No full text© 2019, Ecozone, OAIMDD. All rights reserved. Irinarkh Polikhronievich Skvortzov was a famous Russian scientist. He was born on 5 August, 1847. I.P. Skvortzov graduated from Imperial Kazan University with MD degree. All his life was connected with medical and educational activities. Scientific interests mainly concerned hygiene and microbiology. He was the author of some original microbiological hypothesis. I.P. Skvortzov made a great input to Russian and international science in the end of XIX century. This historical review opens for the first time I.P. Skvortzov for Western readers
Notes on meteorological balloon mission planning
No full textIn the 21st century the high altitude gas balloon remains an indispensable tool in atmospheric science, meteorology and other applications requiring stratospheric observations. A prerequisite of the effectiveness of many types of balloon operations is an accurate trajectory forecasting capability, complete with appropriate error estimates. This is particularly important in targeted flights, sample return missions or flights of expensive instruments, whose recovery is essential. The ASTRA (Atmospheric Science Through Robotic Aircraft) initiative led to the development of such a forecast model, which is at the centre of the present paper. A key source of error in such models is our incomplete understanding of the drag opposing the rise of balloons in the free atmosphere – here we propose a new, stochastic model based on empirical data derived from thousands of radiosonde flights. We also examine other sources of prediction error affecting the accuracy of the flight path forecast, such as uncertainties in the wind profile and balloon envelope manufacturing variability. A Monte Carlo framework is used to provide probabilistic touchdown point estimates taking these error sources into account. The above elements have been integrated into a web service, which can be used as a flight planning tool – here we review the key features of its architecture
Integrating ecology with hydromorphology: a priority for river science and management
No full text1. The assessment of links between ecology and physical habitat has become a major issue in river research and management. Key drivers include concerns about the conservation implications of human modifications (e.g. abstraction, climate change) and the explicit need to understand the ecological importance of hydromorphology as prescribed by the EU's Water Framework Directive. Efforts are focusing on the need to develop eco-hydromorphology at the interface between ecology, hydrology and fluvial geomorphology. Here, the scope of this emerging field is defined, some research and development issues are suggested, and a path for development is sketched out.
2. In the short term, major research priorities are to use existing literature or data better to identify patterns among organisms, ecological functions and river hydromorphological character. Another early priority is to identify model systems or organisms to act as research foci. In the medium term, the investigation of pattern-processes linkages, spatial structuring, scaling relationships and system dynamics will advance mechanistic understanding. The effects of climate change, abstraction and river regulation, eco-hydromorphic resistance/resilience, and responses to environmental disturbances are likely to be management priorities. Large-scale catchment projects, in both rural and urban locations, should be promoted to concentrate collaborative efforts, to attract financial support and to raise the profile of eco-hydromorphology.
3. Eco-hydromorphological expertise is currently fragmented across the main contributory disciplines (ecology, hydrology, geomorphology, flood risk management, civil engineering), potentially restricting research and development. This is paradoxical given the shared vision across these fields for effective river management based on good science with social impact. A range of approaches is advocated to build sufficient, integrated capacity that will deliver science of real management value over the coming decades
Maxim Gorky and the Publishing House of I.P. Ladyzhnikov (Based on Archival Materials)
No full textBased on the hitherto unpublished archival materials, this article examines the history of creation and specific traits of an obscure small Russophone Publishing house of I.P. Ladyzhnikov. It also analyzes the role and the scope of Maxim Gorky’s contribution to the work of this publishing house. It is shown that Gorky was one of the founders of this Berlin-based firm. Not only was he an ideological inspirator of this new business, he also supported it financially. As a result of collective efforts on behalf of Gorky and prominent leaders of the Bolshevik party in 1905, the Russianlanguage publishing house was established abroad. By publishing the works of Gorky and other democratic writers of the Znanie group, it secured their copyright in Europe and America and contributed part of its income to the Bolshevik party funds. In 1905–1912, under the direction of Ladyzhnikov, all new works of Gorky were published by this press. The peak of the Publishing house of I.P. Ladyzhnikov fell upon the most fruitful creative period in the life of the main author of this publishing house — M. Gorky. At the end of 1912 Ladyzhnikov was forced to transfer his business to his partner — B.N. Rubinstein, due to financial difficulties. However, the publishing house continued to exist until 1932. The article examines in detail the lesser-studied postrevolutionary period of the Publishing house of I.P. Ladyzhnikov under the leadership of Rubinstein and demonstrates Rubinstein’s significant participation in the translation and publication of Gorky’s works, including translations and productions of his plays abroad
Impact of Crisis on Logistics Management
No full textIs the current situation facing the whole world and we need to adapt to withstand a fierce weather. Because the supply, which can be seen both as a sale (the manufacturers buy from suppliers) as well as a purchase (customers are supplied by producers) is the center of activities, we believe that a interpretation and a strategic direction to increase the competitiveness of extended supply chain, represents an initial starting point to save the current situation. We must understand that do not survive the nicest, smartest or the strongest, is the future of those who adapt best to change. In the global crisis context we must consider first the potential and not the market. Apparently the market is in a total collapse, but the potential still exists, even at minimum capacity it should work. Now they will be able to support only companies that eliminate almost all their losses and best manages their resources and activities.supply chain management; global crisis; restarting the business; procurement cycle.
Flow over cube arrays of different packing densities
No full textMeasurements by 120° x-wire anemometry over uniform urban-type surfaces of two different area densities were performed in a wind tunnel, together with direct measurements of the surface drag. The aerodynamic characteristics of each surface were determined and compared, the influence of area density and array geometry on these parameters was examined. Various approaches were discussed for the determination of the roughness length (z0) for a given surface. The surface shear stress (determined from form drag measurements by pressure tapping a roughness element or from the total surface drag determined by a floating drag balance) and the shear stress (determined from spatially averaged vertical profiles of Reynolds shear stress) were compared. The surface shear stress was found to be about 25% greater than the measured Reynolds shear stress in the inertial sub-layer over the surfaces. There was, however, no constant stress region and extrapolation of the shear stress profiles in the inertial sub-layer to the zero-plane displacement provided a much better estimate of the surface shear stress. The results did not support the argument put forward in the literature that the zero-plane displacement could be reliably predicted from the height of the centre of drag force. Finally, the accuracy of existing geometrical methods of determining the aerodynamic properties of rough surfaces was shown to be limited by the use of inappropriate wind tunnel data in their formulation
Non-hermetic techniques for low cost, high performance, opto-electronic component assembly
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Design, Optimization, and Evaluation of a Path Query System
No full textThe model of the Universe of Discourse usually needs to be mapped onto the information technology environment chosen by the engineers. This mapping costs significant efforts, time and energy to construct, to use, and to maintain. All these efforts, time and energy can be saved, if the engineers choose an object data management system based on an object model powerful enough to be used to construct the model of the Universe of Discourse. The query language and the query subsystem of an object data management system based on a powerful object model must be different from other query languages and subsystems, because the underlying data model is different. The goal of this research was twofold: (1) to create a query language for such an object data management system, which encourages the formulation of semantically sound queries, supports the formulation of reusable queries, facilitates the usage of recursive queries through intuitive syntax and semantics, and (2) to verify the created query language by the design, optimization and evaluation of a query system whose primary interface is the created query language, and which enables flexible, online, user-defined consistency control of the entered data. This thesis gives an introduction to query systems, and to Perspective-DB that is an object data management system based on a powerful object model. Furthermore, this thesis gives insight into the development stages of the path query system: simple path expressions, active views, combination of path expressions, filtered path expressions, and recursive path expressions. It also describes the way the query subsystem is reused to extend the export and import facilities of the data management system. It features a functional description of the query system and of the parts of the data management system relevant to the query system, and it also handles implementation and maintenance details.Electrical Engineering, Mathematics and Computer Scienc
De doelmatigheid van de Amsterdamsche broodvoorziening
No full textMechanical, Maritime and Materials Engineerin
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