In high-performance computing on distributed-memory systems, communication often represents a significant part of the overall execution time. The relative cost of communication will certainly continue to rise as compute-density growth follows the current technology and industry trends. Design of lower-communication alternatives to fundamental computational algorithms has become an important field of research. For distributed 1-D FFT, communication cost has hitherto remained high as all industry-standard implementations perform three all-to-all internode data exchanges (also called global transposes). These communication steps indeed dominate execution time. In this paper, we present a mathematical framework from which many single-all-to-all and easy-to-implement 1-D FFT algorithms can be derived. For large-scale problems, our implementation can be twice as fast as leading FFT libraries on state-of-the-art computer clusters. Moreover, our framework allows tradeoff between accuracy and performance, further boosting performance if reduced accuracy is acceptable.

The paper presents a new development by Lingvistica ‘98 Inc.: the PG-PARS computer-assisted translation system and a series of professional bidirectional dictionaries. PG-PARS was designed as a Windows 95 and Windows 98 application to support English-Russian-English and English-Ukrainian-English dictionaries. PG-PARS dictionaries are all bidirectional, i.e. they include, for example, both the English-Russian and Russian-English parts. Each part has its alphabetical index of entries displayed on a separate tab in the PG-PARS main window. The word entries are displayed for both parts of the dictionary, and translations of translations can be found easily, which is useful for a professional translator. One of the main peculiarities of PG-PARS is the Smart search mode based on morphological analysis of Slavic and English words looked up in the dictionaries. This is especially beneficial if the user is not a native speaker of Russian and Ukrainian. Another important feature is the Selection option which allows the user to mark a portion of the dictionary entry and paste it into the text. The presentation will show professional applications of the PG-PARS system for translating Russian and English texts.