Follow ing the fram ew ork of the finite elem ent m ethods based on Riesz-representing operators developed by Duan Huoyuan in 1997,through discreteRieszrepresenting-operators on som e virtual(non-) conform ing finit...Follow ing the fram ew ork of the finite elem ent m ethods based on Riesz-representing operators developed by Duan Huoyuan in 1997,through discreteRieszrepresenting-operators on som e virtual(non-) conform ing finite-dim ensionalsubspaces,a stabilization form ulation is pre- sented for the Stokes problem by em ploying nonconform ing elem ents.This form ulation is uni- form ly coercive and notsubject to the Babus ka-Brezzicondition,and the resulted linear algebraic system is positive definitew ith the spectralcondition num berO(h- 2 ). Quasi-optim alerrorbounds are obtained,which is consistentwith the interpola- tion properties ofthe finite elem entsused.展开更多
Multi-core homogeneous processors have been widely used to deal with computation-intensive embedded applications. However, with the continuous down scaling of CMOS technology, within-die variations in the manufacturin...Multi-core homogeneous processors have been widely used to deal with computation-intensive embedded applications. However, with the continuous down scaling of CMOS technology, within-die variations in the manufacturing process lead to a significant spread in the operating speeds of cores within homogeneous multi-core processors. Task scheduling approaches, which do not consider such heterogeneity caused by within-die variations,can lead to an overly pessimistic result in terms of performance. To realize an optimal performance according to the actual maximum clock frequencies at which cores can run, we present a heterogeneity-aware schedule refining(HASR) scheme by fully exploiting the heterogeneities of homogeneous multi-core processors in embedded domains.We analyze and show how the actual maximum frequencies of cores are used to guide the scheduling. In the scheme,representative chip operating points are selected and the corresponding optimal schedules are generated as candidate schedules. During the booting of each chip, according to the actual maximum clock frequencies of cores, one of the candidate schedules is bound to the chip to maximize the performance. A set of applications are designed to evaluate the proposed scheme. Experimental results show that the proposed scheme can improve the performance by an average value of 22.2%, compared with the baseline schedule based on the worst case timing analysis. Compared with the conventional task scheduling approach based on the actual maximum clock frequencies, the proposed scheme also improves the performance by up to 12%.展开更多
China started the new year by putting its first anti-terrorism law into effect,representing the country’s latest efforts to address the issue at home.The law creates basic rules for conducting counter-terrorism opera...China started the new year by putting its first anti-terrorism law into effect,representing the country’s latest efforts to address the issue at home.The law creates basic rules for conducting counter-terrorism operations and strengthens measures for preventing, handling and pun- ishing those involved in terrorism crimes, in addition to establishing international cooperation channels.展开更多
文摘Follow ing the fram ew ork of the finite elem ent m ethods based on Riesz-representing operators developed by Duan Huoyuan in 1997,through discreteRieszrepresenting-operators on som e virtual(non-) conform ing finite-dim ensionalsubspaces,a stabilization form ulation is pre- sented for the Stokes problem by em ploying nonconform ing elem ents.This form ulation is uni- form ly coercive and notsubject to the Babus ka-Brezzicondition,and the resulted linear algebraic system is positive definitew ith the spectralcondition num berO(h- 2 ). Quasi-optim alerrorbounds are obtained,which is consistentwith the interpola- tion properties ofthe finite elem entsused.
基金Project supported by the National Natural Science Foundation of China(Nos.6122500861373074+3 种基金and 61373090)the National Basic Research Program(973)of China(No.2014CB349304)the Specialized Research Fund for the Doctoral Program of Higher Education,the Ministry of Education of China(No.20120002110033)the Tsinghua University Initiative Scientific Research Program
文摘Multi-core homogeneous processors have been widely used to deal with computation-intensive embedded applications. However, with the continuous down scaling of CMOS technology, within-die variations in the manufacturing process lead to a significant spread in the operating speeds of cores within homogeneous multi-core processors. Task scheduling approaches, which do not consider such heterogeneity caused by within-die variations,can lead to an overly pessimistic result in terms of performance. To realize an optimal performance according to the actual maximum clock frequencies at which cores can run, we present a heterogeneity-aware schedule refining(HASR) scheme by fully exploiting the heterogeneities of homogeneous multi-core processors in embedded domains.We analyze and show how the actual maximum frequencies of cores are used to guide the scheduling. In the scheme,representative chip operating points are selected and the corresponding optimal schedules are generated as candidate schedules. During the booting of each chip, according to the actual maximum clock frequencies of cores, one of the candidate schedules is bound to the chip to maximize the performance. A set of applications are designed to evaluate the proposed scheme. Experimental results show that the proposed scheme can improve the performance by an average value of 22.2%, compared with the baseline schedule based on the worst case timing analysis. Compared with the conventional task scheduling approach based on the actual maximum clock frequencies, the proposed scheme also improves the performance by up to 12%.
文摘China started the new year by putting its first anti-terrorism law into effect,representing the country’s latest efforts to address the issue at home.The law creates basic rules for conducting counter-terrorism operations and strengthens measures for preventing, handling and pun- ishing those involved in terrorism crimes, in addition to establishing international cooperation channels.
