The Experts below are selected from a list of 4098 Experts worldwide ranked by ideXlab platform
Yi-jay Lin - One of the best experts on this subject based on the ideXlab platform.
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Generating efficient local memory access sequences for coupled Subscripts in data-parallel programs
Information Sciences, 2003Co-Authors: Tsung-chuan Huang, Liang-cheng Shiu, Yi-jay LinAbstract:Generating the local memory access sequences is an integral part of compiling a data-parallel program into an SPMD code. Most previous research into local memory access sequences have focused on one-dimensional arrays distributed with CYCLIC(k) distribution. The local memory access sequences for multidimensional arrays with independent Subscripts are produced by repeatedly applying the method for one-dimensional arrays. However, the task becomes highly complex when Subscripts are coupled such that the Subscripts in different dimensions depend on the same loop induction variables. This paper presents an efficient approach to computing the iterations executed on each processor by exploiting repetitive patterns in memory accesses. Smaller iteration tables than those of Ramanujam [Code generation for complex Subscripts in data-parallel programs, in: Z. Li et al. (Eds.), Languages and Compilers for Parallel Computing, Lecture Notes in Computer Science, vol. 1366, Springer-Verlag, Berlin, 1998, pp. 49-63] are used, the iteration gap table is not required. The method has been implemented on an IBM SP2. Experimental results demonstrate the efficiency of the proposed method.
Tsung-chuan Huang - One of the best experts on this subject based on the ideXlab platform.
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The local memory access sequence of multiple induction variables on distributed memory machines
Computers & Electrical Engineering, 2004Co-Authors: Tsung-chuan Huang, Liang-cheng Shiu, Hwa-jyh JeanAbstract:Abstract Generating the local memory access sequence is an important issue while compiling a data-parallel language into an SPMD code. There are many researches dealing with this issue for cyclic(k) distribution in simple Subscripts. But the problem becomes highly complicated when the array references are with complex Subscripts. One of the complex array reference functions is array subscript containing multiple induction variables (MIV Subscripts). MIV is an affine combination of two or more nested loop indices in a single dimension. In this paper, we develop a general method in O(k) time to evaluate the start element for a given global start element. We compute the course distance first, and then traverse the FSM until the start element is found. In our method, the FSM table constructed in the one-level algorithm [J. Parallel Distr. Comput. 26(1) (1995) 72] can be used directly, but in the method of Ramanujam et al. [Languages and Compilers for Parallel Computing, vol. 1366. Springer-Verlag, 1998, p. 49] the l , r vectors of the processor must be evaluated for each global start element and the time-expensive operations like division and mod are required to check the space boundary of processors. Experimental results have revealed our method is more efficient than theirs.
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Generating efficient local memory access sequences for coupled Subscripts in data-parallel programs
Information Sciences, 2003Co-Authors: Tsung-chuan Huang, Liang-cheng Shiu, Yi-jay LinAbstract:Generating the local memory access sequences is an integral part of compiling a data-parallel program into an SPMD code. Most previous research into local memory access sequences have focused on one-dimensional arrays distributed with CYCLIC(k) distribution. The local memory access sequences for multidimensional arrays with independent Subscripts are produced by repeatedly applying the method for one-dimensional arrays. However, the task becomes highly complex when Subscripts are coupled such that the Subscripts in different dimensions depend on the same loop induction variables. This paper presents an efficient approach to computing the iterations executed on each processor by exploiting repetitive patterns in memory accesses. Smaller iteration tables than those of Ramanujam [Code generation for complex Subscripts in data-parallel programs, in: Z. Li et al. (Eds.), Languages and Compilers for Parallel Computing, Lecture Notes in Computer Science, vol. 1366, Springer-Verlag, Berlin, 1998, pp. 49-63] are used, the iteration gap table is not required. The method has been implemented on an IBM SP2. Experimental results demonstrate the efficiency of the proposed method.
Leonid Dubrovinsky - One of the best experts on this subject based on the ideXlab platform.
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high pressure behavior of perovskite fetio subscript 3 dissociation into fe subscript 1 delta ti subscript delta o and fe subscript 1 delta ti subscript 2 delta o subscript 5
Physical Review Letters, 2009Co-Authors: Gerd Steinleneumann, O Narygina, I Kantor, Catherine Mccammon, Vitali B Prakapenka, Varghese Swamy, Leonid DubrovinskyAbstract:The stability of perovskite-structured materials at high pressure and temperature is of fundamental interest in solid-state physics, chemistry, and the geosciences. As an alternative to decomposition into oxides or transformation of the CaIrO{sub 3} postperovskite structure, we observe in situ the breakdown of FeTiO{sub 3} perovskite into a (Fe{sub 1-{delta}},Ti{sub {delta}})O+Fe{sub 1+{delta}}Ti{sub 2-{delta}}O{sub 5} assemblage beyond 53 GPa and 2000 K. The high-pressure high-temperature phase of Fe{sub 1+{delta}}Ti{sub 2-{delta}}O{sub 5} with a new structure (space group C2/c) could be preserved on decompression to 9 GPa, and amorphizes under further pressure release. Our study demonstrates that perovskite-structured materials can undergo chemical changes and form complex oxides with new structures, rather than only transform to denser polymorphs or decompose to simple oxides.
Liang-cheng Shiu - One of the best experts on this subject based on the ideXlab platform.
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The local memory access sequence of multiple induction variables on distributed memory machines
Computers & Electrical Engineering, 2004Co-Authors: Tsung-chuan Huang, Liang-cheng Shiu, Hwa-jyh JeanAbstract:Abstract Generating the local memory access sequence is an important issue while compiling a data-parallel language into an SPMD code. There are many researches dealing with this issue for cyclic(k) distribution in simple Subscripts. But the problem becomes highly complicated when the array references are with complex Subscripts. One of the complex array reference functions is array subscript containing multiple induction variables (MIV Subscripts). MIV is an affine combination of two or more nested loop indices in a single dimension. In this paper, we develop a general method in O(k) time to evaluate the start element for a given global start element. We compute the course distance first, and then traverse the FSM until the start element is found. In our method, the FSM table constructed in the one-level algorithm [J. Parallel Distr. Comput. 26(1) (1995) 72] can be used directly, but in the method of Ramanujam et al. [Languages and Compilers for Parallel Computing, vol. 1366. Springer-Verlag, 1998, p. 49] the l , r vectors of the processor must be evaluated for each global start element and the time-expensive operations like division and mod are required to check the space boundary of processors. Experimental results have revealed our method is more efficient than theirs.
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Generating efficient local memory access sequences for coupled Subscripts in data-parallel programs
Information Sciences, 2003Co-Authors: Tsung-chuan Huang, Liang-cheng Shiu, Yi-jay LinAbstract:Generating the local memory access sequences is an integral part of compiling a data-parallel program into an SPMD code. Most previous research into local memory access sequences have focused on one-dimensional arrays distributed with CYCLIC(k) distribution. The local memory access sequences for multidimensional arrays with independent Subscripts are produced by repeatedly applying the method for one-dimensional arrays. However, the task becomes highly complex when Subscripts are coupled such that the Subscripts in different dimensions depend on the same loop induction variables. This paper presents an efficient approach to computing the iterations executed on each processor by exploiting repetitive patterns in memory accesses. Smaller iteration tables than those of Ramanujam [Code generation for complex Subscripts in data-parallel programs, in: Z. Li et al. (Eds.), Languages and Compilers for Parallel Computing, Lecture Notes in Computer Science, vol. 1366, Springer-Verlag, Berlin, 1998, pp. 49-63] are used, the iteration gap table is not required. The method has been implemented on an IBM SP2. Experimental results demonstrate the efficiency of the proposed method.
Gerd Steinleneumann - One of the best experts on this subject based on the ideXlab platform.
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high pressure behavior of perovskite fetio subscript 3 dissociation into fe subscript 1 delta ti subscript delta o and fe subscript 1 delta ti subscript 2 delta o subscript 5
Physical Review Letters, 2009Co-Authors: Gerd Steinleneumann, O Narygina, I Kantor, Catherine Mccammon, Vitali B Prakapenka, Varghese Swamy, Leonid DubrovinskyAbstract:The stability of perovskite-structured materials at high pressure and temperature is of fundamental interest in solid-state physics, chemistry, and the geosciences. As an alternative to decomposition into oxides or transformation of the CaIrO{sub 3} postperovskite structure, we observe in situ the breakdown of FeTiO{sub 3} perovskite into a (Fe{sub 1-{delta}},Ti{sub {delta}})O+Fe{sub 1+{delta}}Ti{sub 2-{delta}}O{sub 5} assemblage beyond 53 GPa and 2000 K. The high-pressure high-temperature phase of Fe{sub 1+{delta}}Ti{sub 2-{delta}}O{sub 5} with a new structure (space group C2/c) could be preserved on decompression to 9 GPa, and amorphizes under further pressure release. Our study demonstrates that perovskite-structured materials can undergo chemical changes and form complex oxides with new structures, rather than only transform to denser polymorphs or decompose to simple oxides.
