Tài liệu HIGH PERFORMANCE DRIVES Chapter1 ppt

... (2.56). Additionally, transition from one vector to the other takes place at much higher frequency than the HIGH PERFORMANCE DRIVES  E Levi, 2001 32 output frequency and each vector is utilised many ... the HIGH PERFORMANCE DRIVES  E Levi, 2001 35 inverter is now capable of controlling both the frequency and the rms value of the fundamental component of the output voltage. Add...

Ngày tải lên: 26/12/2013, 01:17

... HIGH PERFORMANCE DRIVES  E Levi, 2001 50 regarded as constant). Equations derived for the current-fed ... sensors are used in the air-gap of the machine, displaced by 90 degrees). Magnitude and HIGH PERFORMANCE DRIVES  E Levi, 2001 51 position of the rotor flux space vector can then be obtained ... (2.24)-(2.26), together with flux linkage equations (2.21), suggests the follow...

Ngày tải lên: 26/12/2013, 01:17

... analyzing the performance using them the user can locate the program area in which a performance problem lies. Correcting these problems can improve the program performance. Figure 9 shows performance ... the achievable theoretical peak performance from the basic performance character- istics of an architecture such as memory bandwidth and peak performance. If performance is lim...

Ngày tải lên: 24/12/2013, 19:15

... a cluster of SMP’s which are interconnected by a high speed network switch, and each node comprises eight vector PE’s. In order to achieve high performance in such an architecture, the intra-node ... optical transition in higher energy region is also available in such nanotubes according to our first-principles calculation of dipole-matrix elements. We suspected that such high- energy e...

Ngày tải lên: 24/12/2013, 19:15

... Erlangen-N¨urnberg, Cauerstraße 4, D-91058 Erlangen, Germany, {kberonov,durst,noezyilm}@lstm.uni-erlangen.de, 2 High Performance Computing Center Stuttgart (HLRS), Nobelstraße 19, D-70569 Stuttgart, Germany Abstract ... is presented in Fig. 4. It is clear that substantially higher Re than the maximal one showninthatFigure,Re τ ≈ 640, are required in order to quantify the high- Re asympto...

Ngày tải lên: 24/12/2013, 19:15

... gen- erality, we consider queries that involve only one aggregate function and a single join. High- Performance Parallel Database Processing and Grid Databases, by David Taniar, Clement Leung, ... table S in each processor is carried out after the distribution phase. Several things need to be highlighted from this scheme. ž First, the grouping is still performed before the join (although ....

Ngày tải lên: 21/01/2014, 18:20

... since there is only one global index shared by all processors, the height of the tree index is higher than local NRI index trees. Another difference lies in the overlapping of nodes in each level. ... not partitioned like in NRI. Therefore, it can be expected that the height of the index tree is higher, which is similar to that of the PRI structures. Second, the sizes of data pointers and nod...

Ngày tải lên: 21/01/2014, 18:20

... the chances of data being corrupted are high because of the lack of a global management system. Various relaxed consistency requirements have been High- Performance Parallel Database Processing ... Chapter 10 Transactions in Distributed and Grid Databases proposed for data management in Grids. High- precision data-centric scientific appli- cations cannot tolerate any inconsistency. This...

Ngày tải lên: 21/01/2014, 18:20

... centralized and distributed recovery models. Correctness of the recovery protocol is also given. High- Performance Parallel Database Processing and Grid Databases, by David Taniar, Clement Leung, ... coordinator broadcasts the decision. Many variations and optimizations have been proposed to increase the performance of 2PC. But homogeneity and synchronous communication among sites is the...

Ngày tải lên: 21/01/2014, 18:20

... association rules, have been focusing on this phase only. Improving the performance of this phase is critical to the overall performance. This section, focusing on parallel association rules, starts ... involved in enumerating the corresponding support of all frequent itemsets from a high- dimensional dataset is also high. This is one of the reasons that parallelism is desirable. To sho...

Ngày tải lên: 21/01/2014, 18:20