9,401 research outputs found
Digital receiver simulation
Digital simulation of the data link for the Saturn-Uranus spacecraft design is summarized. The data link is a 40 watt, 400 MegaHertz, 44 bit-a-second link, a power starved link, and uses convolution coding. Aspects of the link of particular interest are atmospheric scintillation and the Doppler to data rate ratio. The major characteristics of the scintillation are modeled in terms of tapped delay lines. A candidate system design and receiver design is developed. A computer flow diagram depicting a routine for the error rate and one for acquisition is presented. Various coding algorithms are analyzed since the convolution code is sensitive to the distribution of error and the actual pattern of the error
Communications constraints on a Jupiter probe mission
The use of the Saturn Uranus telemetry design for Jupiter entry requires the following qualifications in space probe data handling: A single dump substitute for the dual damp, a reduction in the neutral mass spectrometer rate, and providing that a second burn is made, a delta V correction
Reforming the public pension scheme in Germany: The end of the traditional consensus?
The public pension scheme has been an important element of the successful model of 'Rhenish Capitalism' (social market economy) in post-war Germany. On the one hand, the promise to guarantee status maintenance during retirement sustained the incentives of the labor market in that it promoted individual effort and mobility. On the other hand, the public pension scheme definitely contributed to the legitimization of democratic politics because it corresponded to approved notions of social justice. Not the least for these reasons, in the end, this branch of the social insurance system developed with general approval from the governing parties, the party in opposition, and the social partners. After the legislation of the public pensions reform in 1989 (which became effective in 1992) it was assumed that in Germany no further structural reform should enter the political agenda during this century. Nevertheless, in 1997 another far-reaching reform proposal was enacted in 1997 (Rentenreform 1999). In the paper the background of the revived reform debate, the (disputed) elements of the reform proposal(s), and the process of compromise-building are analyzed. Special emphasis will be given to the question of whether the conflictuous reform process and the still ongoing debate indicate an end to the long-standing consensus between the large political parties and between the social partners which has prevailed in German pension politics so far and that would be, at the same time, an expression and result of notable changes of the politico-economical conditions in Germany. --
Between continuity and paradigm shift: Pension reforms in Germany
In general, the policy domain of old-age pensions is characterized by institutional continuity and only incremental reforms. Since the late 1980s, in Germany a series of public pension reforms, all initiated in view of imminent population aging, have happened. In this paper it is looked into the process and content of reforms legislated between 1989 and 2001 in order to understand the nature of change and its driving forces. The main question to be answered is whether these single reform steps eventually amounted to a 'path departure'. Despite the reforms the public pension scheme will continue to be the central component of retirement income for the next decades to come, and traditional features of that social insurance program remained intact. However, it can no longer be regarded as a coherent and undisputed policy paradigm: pension politics has become increasingly conflictuous, and the scope of policy-making has widened from public pension policy (parametric reforms concerning a tighter contribution-benefit link, prolonged working life, adjustment formulae etc.) to retirement income policy. Thereby some of the public scheme's established principles have been abandoned, non-public components of retirement income are pushed and new actors become involved in the politics of pensions. It is thus justified to speak of a paradigmatic change that has occurred. --
From chunks to function-argument structure : a similarity-based approach
Chunk parsing has focused on the recognition of partial constituent structures at the level of individual chunks. Little attention has been paid to the question of how such partial analyses can be combined into larger structures for complete utterances. Such larger structures are not only desirable for a deeper syntactic analysis. They also constitute a necessary prerequisite for assigning function-argument structure. The present paper offers a similaritybased algorithm for assigning functional labels such as subject, object, head, complement, etc. to complete syntactic structures on the basis of prechunked input. The evaluation of the algorithm has concentrated on measuring the quality of functional labels. It was performed on a German and an English treebank using two different annotation schemes at the level of function argument structure. The results of 89.73% correct functional labels for German and 90.40%for English validate the general approach
TĂźSBL : a similarity-based chunk parser for robust syntactic processing
Chunk parsing has focused on the recognition of partial constituent structures at the level of individual chunks. Little attention has been paid to the question of how such partial analyses can be combined into larger structures for complete utterances. The TĂźSBL parser extends current chunk parsing techniques by a tree-construction component that extends partial chunk parses to complete tree structures including recursive phrase structure as well as function-argument structure. TĂźSBLs tree construction algorithm relies on techniques from memory-based learning that allow similarity-based classification of a given input structure relative to a pre-stored set of tree instances from a fully annotated treebank. A quantitative evaluation of TĂźSBL has been conducted using a semi-automatically constructed treebank of German that consists of appr. 67,000 fully annotated sentences. The basic PARSEVAL measures were used although they were developed for parsers that have as their main goal a complete analysis that spans the entire input.This runs counter to the basic philosophy underlying TĂźSBL, which has as its main goal robustness of partially analyzed structures
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