Delta method, an empirical drag buildup technique

An empirical drag correlation technique was developed from analysis of 19 subsonic and supersonic military aircraft and 15 advanced or supercritical airfoil configurations which can be applied in conceptual and advanced aircraft design activities. The Delta Method may be used for estimating the clean wing drag polar for cruise and maneuver conditions up to buffet onset, and to approximately Mach 2.0. This technique incorporates a unique capability of predicting the off-design performance of advanced or supercritical airfoil sections. The buffet onset limit may also be estimated. The method is applicable to wind tunnel models as well as to full scale configurations. This technique has been converted into a computer code for use on the IBM 360 and CDC 7600 computer facilities at NASA AMES. Results obtained using this method to predict known aircraft characteristics are good and agreement can be obtained within a degree of accuracy judged to be sufficient for the initial processes of preliminary design

Management, worker responses and an enterprise trade union in transition

We examine management and labour process changes in a Moldovan factory to examine their impact on the trade union and to test the utility of institutionalist approaches. Changes in management structures and work organisation have hollowed out key legacies, notably the ‘labour collective’ and informal bargaining, and evoked resistance from workers. The union is disconnected from worker resistance and is faced with major issues concerning its role. We conceptualise it as a ‘suspended institution’

Evolving database systems : a persistent view

Submitted to POS7 This work was supported in St Andrews by EPSRC Grant GR/J67611 "Delivering the Benefits of Persistence"Orthogonal persistence ensures that information will exist for as long as it is useful, for which it must have the ability to evolve with the growing needs of the application systems that use it. This may involve evolution of the data, meta-data, programs and applications, as well as the users' perception of what the information models. The need for evolution has been well recognised in the traditional (data processing) database community and the cost of failing to evolve can be gauged by the resources being invested in interfacing with legacy systems. Zdonik has identified new classes of application, such as scientific, financial and hypermedia, that require new approaches to evolution. These applications are characterised by their need to store large amounts of data whose structure must evolve as it is discovered by the applications that use it. This requires that the data be mapped dynamically to an evolving schema. Here, we discuss the problems of evolution in these new classes of application within an orthogonally persistent environment and outline some approaches to these problems.Postprin

On the unification of geodetic leveling datums using satellite altimetry

Techniques are described for determining the height of Mean Sea Level (MSL) at coastal sites from satellite altimetry. Such information is of value in the adjustment of continental leveling networks. Numerical results are obtained from the 1977 GEOS-3 altimetry data bank at Goddard Space Flight Center using the Bermuda calibration of the altimeter. Estimates are made of the heights of MSL at the leveling datums for Australia and a hypothetical Galveston datum for central North America. The results obtained are in reasonable agreement with oceanographic estimates obtained by extrapolation. It is concluded that all gravity data in the Australian bank AUSGAD 76 and in the Rapp data file for central North America refer to the GEOS-3 altimeter geoid for 1976.0 with uncertainties which do not exceed + or - 0.1 mGal

Mach-Zehnder optical configuration with Brewster window and two quarter-wave plates

Configuration is improvement because of the following: It provides higher efficiency. It reduces or eliminates feedthrough of untranslated local oscillator, which would produce a beat signal at shifted frequency of translator. When used without translator and with low-power detector, telescope secondary mirror reflects portion of output to local oscillator

Linguistic Reflection in Java

Reflective systems allow their own structures to be altered from within. Here we are concerned with a style of reflection, called linguistic reflection, which is the ability of a running program to generate new program fragments and to integrate these into its own execution. In particular we describe how this kind of reflection may be provided in the compiler-based, strongly typed object-oriented programming language Java. The advantages of the programming technique include attaining high levels of genericity and accommodating system evolution. These advantages are illustrated by an example taken from persistent programming which shows how linguistic reflection allows functionality (program code) to be generated on demand (Just-In-Time) from a generic specification and integrated into the evolving running program. The technique is evaluated against alternative implementation approaches with respect to efficiency, safety and ease of use.Comment: 25 pages. Source code for examples at http://www-ppg.dcs.st-and.ac.uk/Java/ReflectionExample/ Dynamic compilation package at http://www-ppg.dcs.st-and.ac.uk/Java/DynamicCompilation

A discontinuous Galerkin method for the Vlasov-Poisson system

A discontinuous Galerkin method for approximating the Vlasov-Poisson system of equations describing the time evolution of a collisionless plasma is proposed. The method is mass conservative and, in the case that piecewise constant functions are used as a basis, the method preserves the positivity of the electron distribution function and weakly enforces continuity of the electric field through mesh interfaces and boundary conditions. The performance of the method is investigated by computing several examples and error estimates associated system's approximation are stated. In particular, computed results are benchmarked against established theoretical results for linear advection and the phenomenon of linear Landau damping for both the Maxwell and Lorentz distributions. Moreover, two nonlinear problems are considered: nonlinear Landau damping and a version of the two-stream instability are computed. For the latter, fine scale details of the resulting long-time BGK-like state are presented. Conservation laws are examined and various comparisons to theory are made. The results obtained demonstrate that the discontinuous Galerkin method is a viable option for integrating the Vlasov-Poisson system.Comment: To appear in Journal for Computational Physics, 2011. 63 pages, 86 figure

Migration, ethnicity and solidarity: 'multinational workers' in the former Soviet Union

We investigate migrant construction workers’ experiences in the Former Soviet Union, examining their attitudes to other ethno-national groups, unions and collective action. Industrial relations and migration studies view migrant workers’ hypermobility and diversity, under conditions of low union coverage and rising nationalism, as potentially obstructing consciousness-raising and mobilizing. Workers in our study faced union indifference, ethno-national segregation and discrimination. However, managerial abuses, informality and contestation from below led to spontaneous mobilisation. Lack of institutional channels to solve these disputes drove workers’ further mobility. Complex mobility trajectories and collective action translated into increased awareness of collective interests and rejection of nationalist ideologies. The outcome is ‘multinational workers’ potentially resistant to nation-state politics and capital’s logics but also aware of the value and usefulness of collective solidarities. Thus, previous arguments solely associating exit with individualistic attitudes, and post-socialist legacies with workers’ quiescence present only partial pictures

Pay and employee intrapreneurialism in Russia, 1994-2015: a longitudinal study

We examine whether a high wage-high employee intrapreneurial inputs model remains a significant feature of the Russian economy. We do so by estimating the evolution of employee ‘intrapreneurial’ contributions to companies in Russia,1994-2015, using Akerlof’s theory of ‘partial gift exchange’. Akerlof (1982) suggests that employee discretionary contributions to organisational capacities rise when pay exceeds employee perceptions of ‘fair’ pay in comparable employment. Using the extensive Russian Longitudinal Monitoring Survey (RLMS), we find that overall employee intrapreneurial contributions significantly declined, 1994-2015, mirroring the declining Akerlof wage premium. Intrapreneurialism in highly-informalized sectors was associated with labour market pressures. We extend Akerlof’s theory to recognize intrapreneurial activity associated with coercive labour market pressures in the secondary labour market