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101.
Register allocation for write activity minimization on non-volatile main memory for embedded systems
Yazhi Huang Author VitaeTiantian Liu Author Vitae Chun Jason XueAuthor Vitae 《Journal of Systems Architecture》2012,58(1):13-23
Non-volatile memories are good candidates for DRAM replacement as main memory in embedded systems and they have many desirable characteristics. Nevertheless, the disadvantages of non-volatile memory co-exist with its advantages. First, the lifetime of some of the non-volatile memories is limited by the number of erase operations. Second, read and write operations have asymmetric speed or power consumption in non-volatile memory. This paper focuses on the embedded systems using non-volatile memory as main memory. We propose register allocation technique with re-computation to reduce the number of store instructions. When non-volatile memory is applied as the main memory, reducing store instructions will reduce write activities on non-volatile memory. To re-compute the spills effectively during register allocation, a novel potential spill selection strategy is proposed. During this process, live range splitting is utilized to split certain long live ranges such that they are more likely to be assigned into registers. In addition, techniques for re-computation overhead reduction is proposed on systems with multiple functional units. With the proposed approach, the lifetime of non-volatile memory is extended accordingly. The experimental results demonstrate that the proposed technique can efficiently reduce the number of store instructions on systems with non-volatile memory by 33% on average. 相似文献
102.
Insulator-based dielectrophoresis (iDEP) has been successfully used for on-chip manipulations of biological samples. Despite
its effectiveness, iDEP typically requires high DC voltages to achieve sufficient electric field; this is mainly due to the
coupled phenomena among linear electrokinetics: electroosmosis (EO) and electrophoresis (EP) and nonlinear electrokinetics:
dielectrophoresis (DEP). This paper presents a microfluidic technique using DC-offset AC electric field for electrokinetic
concentration of particles and cells by repulsive iDEP. This technique introduces AC electric field for producing iDEP which
is decoupled from electroosmosis (EO) and electrophoresis (EP). The repulsive iDEP is generated in a PDMS tapered contraction
channel that induces non-uniform electric field. The benefits of introducing AC electric field component are threefold: (i)
it contributes to DEP force acting on particles, (ii) it suppresses EO flow and (iii) it does not cause any EP motion. As
a result, the required DC field component that is mainly used to transport particles on the basis of EO and EP can be significantly
reduced. Experimental results supported by numerical simulations showed that the total DC-offset AC electric field strength
required to concentrate 15-μm particles is significantly reduced up to 85.9% as compared to using sole DC electric field.
Parametric experimental studies showed that the higher buffer concentration, larger particle size and higher ratio of AC-to-DC
electric field are favorable for particle concentration. In addition, the proposed technique was demonstrated for concentration
of yeast cells. 相似文献
103.
104.
本文提出:所谓“荧光扫描法”测定杂交水稻子一代种子纯度的方法,不是测定的荧光,而是测定的散射光,由种子表面对光的散射来进行测定。因而实质上仍然是一种形态学的测定方法。 相似文献
105.
106.
焊接生产规模不断向自动化和流水线方式发展 ,对生产管理水平提出了更高的要求。为了从车间已积累的大量的生产历史数据中获得潜在的规律性和趋势 ,为管理者提供决策支持 ,文中在已有的质量在线监测平台和数据库系统上开发了基于先进的数据挖掘技术的焊接生产管理平台 ,同时为了获得有效的挖掘模式 ,对数据进行了预处理 ,建立了焊接车间数据集市。该平台主要使用控制图控制焊接生产产量和废品数量 ;利用决策树方法分析废品产生因素 ,获得了有效的挖掘模型 ,对于指导焊接生产具有重要意义 相似文献
107.
阐述了180kA大型铝电解槽槽壳的位移现场测试手段、槽壳表面位移特征和槽壳所受内力的计算方法,并对槽壳结构优化设计做了分析 相似文献
108.
109.
110.
Maria Immaculata Arifin Samia Hannaoui Sheng Chun Chang Simrika Thapa Hermann M. Schatzl Sabine Gilch 《International journal of molecular sciences》2021,22(5)
Chronic wasting disease (CWD) is a prion disease found in both free-ranging and farmed cervids. Susceptibility of these animals to CWD is governed by various exogenous and endogenous factors. Past studies have demonstrated that polymorphisms within the prion protein (PrP) sequence itself affect an animal’s susceptibility to CWD. PrP polymorphisms can modulate CWD pathogenesis in two ways: the ability of the endogenous prion protein (PrPC) to convert into infectious prions (PrPSc) or it can give rise to novel prion strains. In vivo studies in susceptible cervids, complemented by studies in transgenic mice expressing the corresponding cervid PrP sequence, show that each polymorphism has distinct effects on both PrPC and PrPSc. It is not entirely clear how these polymorphisms are responsible for these effects, but in vitro studies suggest they play a role in modifying PrP epitopes crucial for PrPC to PrPSc conversion and determining PrPC stability. PrP polymorphisms are unique to one or two cervid species and most confer a certain degree of reduced susceptibility to CWD. However, to date, there are no reports of polymorphic cervid PrP alleles providing absolute resistance to CWD. Studies on polymorphisms have focused on those found in CWD-endemic areas, with the hope that understanding the role of an animal’s genetics in CWD can help to predict, contain, or prevent transmission of CWD. 相似文献